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Mammalian nasal capsule development has been described in only a few cross-sectional age series, rendering it difficult to infer developmental mechanisms that influence adult morphology. Here we examined a sample of Leschenault's rousette fruit bats (Rousettus leschenaultii) ranging in age from embryonic to adult (n=13). We examined serially sectioned coronal histological specimens, and used micro computed tomography scans to visualize morphology in two older specimens. We found that the development of the nasal capsule in Rousettus proceeds similarly to many previously described mammals, following a general theme in which the central (i.e., septal) region matures into capsular cartilage before peripheral regions, and rostral parts of the septum and paries nasi mature before caudal parts. The ossification of turbinals also generally follows a rostral to caudal pattern. Our results suggest discrete mechanisms for increasing complexity of the nasal capsule, some of which are restricted to the late embryonic and early fetal timeframe, including fissuration and mesenchymal proliferation. During fetal and early postnatal ontogeny, appositional and interstitial chondral growth of cartilage modifies the capsular template. Postnatally, appositional bone growth and pneumatization render greater complexity to individual structures and spaces. Future studies that focus on the relative contribution of each mechanism during development may draw critical inferences how nasal morphology is reflective of, or deviates from the original fetal template. A comparison of other chiropterans to nasal development in Rousettus could reveal phylogenetic patterns (whether ancestral or derived) or the developmental basis for specializations relating to respiration, olfaction, or laryngeal echolocation. This article is protected by copyright. All rights reserved.

Our knowledge of nasal cavity anatomy has grown considerably with the advent of micro-computed tomography (CT). More recently, a technique called diffusible iodine-based contrast-enhanced CT (diceCT) has rendered it possible to study nasal soft tissues. Using diceCT and histology, we aim to (a) explore the utility of these techniques for inferring the presence of venous sinuses that typify respiratory mucosa and (b) inquire whether distribution of vascular mucosa may relate to specialization for derived functions of the nasal cavity (i.e., nasal-emission of echolocation sounds) in bats. Matching histology and diceCT data indicate that diceCT can detect venous sinuses as either darkened, "empty" spaces, or radio-opaque islands when blood cells are present. Thus, we show that diceCT provides reliable information on vascular distribution in the mucosa of the nasal airways. Among the bats studied, a nonecholocating pteropodid (Cynopterus sphinx) and an oral-emitter of echolocation sounds (Eptesicus fuscus) possess venous sinus networks that drain into the sphenopalatine vein rostral to the nasopharynx. In contrast, nasopharyngeal passageways of nasal-emitting hipposiderids are notably packed with venous sinuses. The mucosae of the nasopharyngeal passageways are far less vascular in nasal-emitting phyllostomids, in which vascular mucosae are more widely distributed in the nasal cavity, and in some nectar-feeding species, a particularly large venous sinus is adjacent to the vomeronasal organ. Therefore, we do not find a common pattern of venous sinus distribution associated with nasal emission of sounds in phyllostomids and hipposiderids. Instead, vascular mucosa is more likely critical for air-conditioning and sometimes vomeronasal function in all bats.

The colonial naked mole rat Heterocephalus glaber is a subterranean, eusocial rodent. The H. glaber vomeronasal organ neuroepithelium (VNE) displays little postnatal growth. However, the VNE remains neuronal in contrast to some mammals that possess nonfunctional vomeronasal organ remnants, for example, catarrhine primates and some bats. Here, we describe the vomeronasal organ (VNO) microanatomy in the naked mole rat and we make preliminary observations to determine if H. glaber shares its minimal postnatal VNE growth with other African mole rats. We also determine the immunoreactivity to the mitotic marker Ki67, growth-associated protein 43 (GAP43), and olfactory marker protein (OMP) in six adult and three subadult H. glaber individuals. VNE volume measurements on a small sample of Cryptomys hottentotus and Fukomys damarensis indicate that the VNE of those African mole rat species are also likely to be growth-deficient. Ki67(+) cells show that the sensory epithelium is mitotically active. GAP43 labelling indicates neurogenesis and OMP(+) cells are present though less numerous compared to GAP43(+) cells. In this respect, the VNO of H. glaber does not appear vestigial. The African mole rat VNE may be unusually variable, perhaps reflecting reduced selection pressure on the vomeronasal system. If so, African mole rats may provide a useful genetic model for understanding the morphological variability observed in the mammalian VNO. Anat Rec, 2019. © 2019 Wiley Periodicals, Inc. Anat Rec, 303:318-329, 2020. © 2019 American Association for Anatomy.

Horseshoe bats (Family Rhinolophidae) show an impressive array of morphological traits associated with use of high duty cycle echolocation calls that they emit via their nostrils (nasophonation). Delicate maxilloturbinal bones inside the nasal fossa of horseshoe bats have a unique elongated strand-like shape unknown in other mammals. Maxilloturbinal strands also vary considerably in length and cross-sectional shape. In other mammals, maxilloturbinals help direct respired air and prevent respiratory heat and water loss. We investigated whether strand-shaped maxilloturbinals in horseshoe bats perform a similar function to those of other mammals, or whether they were shaped for a role in nasophonation. Using histology, we studied the mucosa of the nasal fossa in Rhinolophus lepidus, which we compared with Hipposideros lankadiva (Hipposideridae) and Megaderma lyra (Megadermatidae). Using micro-CT scans of 30 horseshoe bat species, we quantified maxilloturbinal surface area and skull shape within a phylogenetic context. Histological results showed horseshoe bat maxilloturbinals are covered in a thin, poorly vascularized, sparsely ciliated mucosa poorly suited for preventing respiratory heat and water loss. Maxilloturbinal surface area was correlated with basicranial width, but exceptionally long and dorsoventrally flat maxilloturbinals did not show enhanced surface area for heat and moisture exchange. Skull shape variation appears to be driven by structures linked to nasophonation, including maxilloturbinals. Resting echolocation call frequency better predicted skull shape than did skull size, and was specifically correlated with dimensions of the rostral inflations, palate, and maxilloturbinals. These traits appear to form a morphological complex, indicating a nasophonatory role for the strand-shaped rhinolophid maxilloturbinals. Anat Rec, 2018. © 2018 American Association for Anatomy.

Integration of the sphenoid and ethmoid bones during early postnatal development is poorly described in the literature. A uniquely prolonged patency of sphenoethmoidal synchondrosis, or prespheno-septal synchondrosis (PSept) has been attributed to humans. However, the sphenoethmoidal junction has not been studied using a comparative primate sample. Here, we examined development of the sphenoethmoidal interface using ontogenetic samples of Old and New World monkeys, strepsirrhine primates (lemurs and lorises), and a comparative sample of other mammals. Specimens ranging from late fetal to one month postnatal age were studied using histology, immunohistochemistry, and micro-computed tomography methods. Our results demonstrate that humans are not unique in anterior cranial base growth at PSept, since it is patent in all newborn primates. We found two distinctions within our sample. First, nearly all primates exhibit an earlier breakdown of the nasal capsule cartilage that abuts the orbitosphenoid when compared to non-primates. This may facilitate earlier postnatal integration of the basicranium and midface and may enhance morphological plasticity in the region. Second, the PSept exhibits a basic dichotomy between strepsirrhines and monkeys. In strepsirrhines, the PSept has proliferating chondrocytes that are primarily oriented in a longitudinal plane, as in other mammals. In contrast, monkeys have a convex anterior end of the presphenoid with a radial boundary of cartilaginous growth at PSept. Our findings suggest that the PSept acts as a "pacemaker" of longitudinal facial growth in mammals with relatively long snouts, but may also contribute to facial height and produce a relatively taller midface in anthropoid primates. This article is protected by copyright. All rights reserved.

Of the principal sensory systems (vision, olfaction, taste, hearing, and balance), olfaction is one of the oldest. This ubiquitous system has both peripheral and central subdivisions. The peripheral subdivision is comprised of the olfactory epithelium and nerve fascicles, whereas the central subdivision is made up of the olfactory bulb and its central connections. Humans lack the "accessory olfactory system" of many other mammals, exhibiting only a nonfunctioning vestige of its peripheral element, the vomeronasal organ. Compared to most mammals, major elements of the human olfactory system are reduced; for example, humans have fewer turbinates than many mammals, and their olfactory epithelia are found only on one or two of these structures and their adjacent surfaces. Nonetheless, humans retain a full complement of functional cellular elements including a regenerating population of olfactory sensory neurons. These neurons extend long ciliary processes into the mucus that form a mat of cilia on which the odorant receptors are located. The olfactory sensory neurons send their axons directly to synapse within the olfactory bulb. Mitral and tufted cells then relay impulses from the bulb to other brain regions. This chapter describes the general anatomy and microanatomy of the olfactory system.

Living primates have relatively large eyes and support orbital tissues with a postorbital bar (POB) and/or septum. Some mammals with large eyes lack a POB, and presumably rely on soft tissues. Here, we examined the orbits of four species of strepsirrhine primates (Galagidae, Cheirogaleidae) and three species of fruit bats (Pteropodidae). Microdissection and light microscopy were employed to identify support structures of the orbit. In bats and primates, there are two layers of fascial sheets that border the eye laterally. The outer membrane is the most superficial layer of deep fascia, and has connections to the POB in primates. In fruit bats, which lacked a POB or analogous ligament, the deep fascia is reinforced by transverse ligaments. Bats and primates have a deeper membrane supporting the eye, identified as the periorbita (PA) based on the presence of elastic fibers and smooth muscle. The PA merges with periostea deep within the orbit, but has no periosteal attachment to the POB of primates. These findings demonstrate that relatively big eyes can be supported primarily with fibrous connective tissues as well as the PA, in absence of a POB or ligament. The well-developed smooth muscle component within the PA of fruit bats likely helps to protrude the eye, maintaining a more convergent eye orientation, with greater overlap of the visual fields. The possibility should be considered that early euprimates, and even stem primates that may have lacked a POB, also had more convergent eyes than indicated by osseous measurements of orbital orientation. Anat Rec, 299:1690-1703, 2016. © 2016 Wiley Periodicals, Inc.

Experimental determination of the eye irritation potential (EIP) of chemicals is not only tedious, time and resource intensive, it involves cruelty to test animals. In this study, we have established a three-tier QSAR modeling strategy for estimating the EIP of chemicals for the use of pharmaceutical industry and regulatory agencies. Accordingly, a qualitative (binary classification: irritating, non-irritating), semi-quantitative (four-category classification), and quantitative (regression) QSAR models employing the SDT, DTF, and DTB methods were developed for predicting the EIP of chemicals in accordance with the OECD guidelines. Structural features of chemicals responsible for eye irritation were extracted and used in QSAR analysis. The external predictive power of the developed QSAR models were evaluated through the internal and external validation procedures recommended in QSAR literature. In test data, the two and four category classification QSAR models (DTF, DTB) rendered accuracy of >93%, while the regression QSAR models (DTF, DTB) yielded correlation (R2) of >0.92 between the measured and predicted EIPs. Values of various statistical validation coefficients derived for the test data were above their respective threshold limits (except r m 2 in DTF), thus put a high confidence in this analysis. The applicability domain of the constructed QSAR models were defined using the descriptors range and leverage approaches. The QSAR models in this study performed better than any of the previous studies. The results suggest that the developed QSAR models can reliably predict the EIP of diverse chemicals and can be useful tools for screening of candidate molecules in the drug development process.

Organic solvents are widely used chemicals and the neurotoxic properties of some are well established. In this study, we established nonlinear qualitative and quantitative structure-toxicity relationship (STR) models for predicting neurotoxic classes and neurotoxicity of structurally diverse solvents in rodent test species following OECD guideline principles for model development. Probabilistic neural network (PNN) based qualitative and generalized regression neural network (GRNN) based quantitative STR models were constructed using neurotoxicity data from rat and mouse studies. Further, interspecies correlation based quantitative activity-activity relationship (QAAR) and global QSTR models were also developed using the combined data set of both rodent species for predicting the neurotoxicity of solvents. The constructed models were validated through deriving several statistical coefficients for the test data and the prediction and generalization abilities of these models were evaluated. The qualitative STR models (rat and mouse) yielded classification accuracies of 92.86% in the test data sets, whereas, the quantitative STRs yielded correlation (R(2)) of >0.93 between the measured and model predicted toxicity values in both the test data (rat and mouse). The prediction accuracies of the QAAR (R(2) 0.859) and global STR (R(2) 0.945) models were comparable to those of the independent local STR models. The results suggest the ability of the developed QSTR models to reliably predict binary neurotoxicity classes and the endpoint neurotoxicities of the structurally diverse organic solvents.

Safety assessment and designing of safer ionic liquids (ILs) are among the priorities of the chemists and toxicologists today. Computational approaches have been considered as appropriate methods for prior safety assessment of chemicals and tools to aid in structural designing. The present study is an attempt to investigate the chemical attributes of a wide variety of ILs towards their cytotoxicity in leukemia rat cell line IPC-81 through the development of nonlinear quantitative structure-activity relationship (QSAR) models in the light of the OECD principles for QSAR development. Here, the cascade correlation network (CCN), probabilistic neural network (PNN), and generalized regression neural networks (GRNN) QSAR models were established for the discrimination of ILs in four categories of cytotoxicity and their end-point prediction using few simple descriptors. The diversity and nonlinearity of the considered dataset were evaluated through computing the Euclidean distance and Brock-Dechert-Scheinkman statistics. The constructed QSAR models were validated with external test data. The predictive power of these models was established through a variety of stringent parameters recommended in QSAR literature. The classification QSARs rendered the accuracy of >86%, and the regression models yielded correlation (R(2)) of >0.90 in test data. The developed QSAR models exhibited high statistical confidence and identified the structural elements of the ILs responsible for their cytotoxicity and, hence, could be useful tools in structural designing of safer and green ILs.

Volatile organic compounds (VOCs) are among the priority atmospheric pollutants that have high indoor and outdoor exposure potential. The toxicity assessment of VOCs to living ecosystems has received considerable attention in recent years. Development of computational methods for safety assessment of chemicals has been advocated by various regulatory agencies. The paper proposes robust and reliable quantitative structure-activity relationships (QSARs) for estimating the sensory irritation potency and screening of the VOCs. Here, decision tree (DT) based classification and regression QSARs models, such as single DT, decision tree forest (DTF), and decision tree boost (DTB) were developed using the sensory irritation data on VOCs in mice following the OECD principles. Structural diversity and nonlinearity in the data were evaluated through the Euclidean distance and Brock-Dechert-Scheinkman statistics. The constructed QSAR models were validated with external test data and the predictive performance of these models was established through a set of coefficients recommended in QSAR literature. The performance of all three classification and regression QSAR models was satisfactory, but DTF and DTB performed relatively better. The classification and regression QSAR models (DTF, DTB) rendered classification accuracies of 98.59 and 100 %, and yielded correlations (R(2)) of 0.950 and 0.971, respectively in complete data. The lipoaffinity index and SwHBa were identified as the most influential descriptors in proposed QSARs. The developed QSARs performed better than the previous studies. The developed models exhibited high statistical confidence and identified the structural properties of the VOCs responsible for their sensory irritation, and hence could be useful tools in screening of chemicals for regulatory purpose.

High concentrations of pharmacological active compounds (PACs) detected in global drinking water resources and their toxicological implications in aquatic life has become a matter of concern compelling for the development of reliable QSTRs (qualitative/quantitative structure–toxicity relationships) for their risk assessment. Robust QSTRs, such as decision treeboost (DTB) and decision tree forest (DTF) models implementing stochastic gradient boosting and bagging algorithms were established by experimental toxicity data of structurally diverse PACs in daphnia using molecular descriptors for predicting toxicity of new untested compounds in multiple test species. Developed models were rigorously validated using OECD recommended internal and external validation procedures and predictive power tested with external data of different trophic level test species (algae and fish). Classification QSTRs (DTB, DTF) rendered accuracy of 98.73% and 97.47%, respectively in daphnia and 84.38%, 85.94% (algae), 78.46% and 79.23% (fish). On the other hand, the regression QSTRs (DTB, DTF) yielded squared correlation coefficient values of 0.831, 0.852 (daphnia), 0.534, 0.556 (algae) and 0.620, 0.637 (fish). QSTRs developed in this study passed the OECD validation criteria and performed better than reported earlier for predicting toxicity of PACs, and can be used for screening the new untested compounds for regulatory purpose.

Pesticides are designed toxic chemicals for specific purposes and can harm nontarget species as well. The honey bee is considered a nontarget test species for toxicity evaluation of chemicals. Global QSTR (quantitative structure-toxicity relationship) models were established for qualitative and quantitative toxicity prediction of pesticides in honey bee (Apis mellifera) based on the experimental toxicity data of 237 structurally diverse pesticides. Structural diversity of the chemical pesticides and nonlinear dependence in the toxicity data were evaluated using the Tanimoto similarity index and Brock-Dechert-Scheinkman statistics. Probabilistic neural network (PNN) and generalized regression neural network (GRNN) QSTR models were constructed for classification (two and four categories) and function optimization problems using the toxicity end point in honey bees. The predictive power of the QSTR models was tested through rigorous validation performed using the internal and external procedures employing a wide series of statistical checks. In complete data, the PNN-QSTR model rendered a classification accuracy of 96.62% (two-category) and 95.57% (four-category), while the GRNN-QSTR model yielded a correlation (R(2)) of 0.841 between the measured and predicted toxicity values with a mean squared error (MSE) of 0.22. The results suggest the appropriateness of the developed QSTR models for reliably predicting qualitative and quantitative toxicities of pesticides in honey bee. Both the PNN and GRNN based QSTR models constructed here can be useful tools in predicting the qualitative and quantitative toxicities of the new chemical pesticides for regulatory purposes.

Robust global models capable of discriminating positive and non-positive carcinogens; and predicting carcinogenic potency of chemicals in rodents were developed. The dataset of 834 structurally diverse chemicals extracted from Carcinogenic Potency Database (CPDB) was used which contained 466 positive and 368 non-positive carcinogens. Twelve non-quantum mechanical molecular descriptors were derived. Structural diversity of the chemicals and nonlinearity in the data were evaluated using Tanimoto similarity index and Brock-Dechert-Scheinkman statistics. Probabilistic neural network (PNN) and generalized regression neural network (GRNN) models were constructed for classification and function optimization problems using the carcinogenicity end point in rat. Validation of the models was performed using the internal and external procedures employing a wide series of statistical checks. PNN constructed using five descriptors rendered classification accuracy of 92.09% in complete rat data. The PNN model rendered classification accuracies of 91.77%, 80.70% and 92.08% in mouse, hamster and pesticide data, respectively. The GRNN constructed with nine descriptors yielded correlation coefficient of 0.896 between the measured and predicted carcinogenic potency with mean squared error (MSE) of 0.44 in complete rat data. The rat carcinogenicity model (GRNN) applied to the mouse and hamster data yielded correlation coefficient and MSE of 0.758, 0.71 and 0.760, 0.46, respectively. The results suggest for wide applicability of the inter-species models in predicting carcinogenic potency of chemicals. Both the PNN and GRNN (inter-species) models constructed here can be useful tools in predicting the carcinogenicity of new chemicals for regulatory purposes.

The research aims to develop global modeling tools capable of categorizing structurally diverse chemicals in various toxicity classes according to the EEC and European Community directives, and to predict their acute toxicity in fathead minnow using set of selected molecular descriptors. Accordingly, artificial intelligence approach based classification and regression models, such as probabilistic neural networks (PNN), generalized regression neural networks (GRNN), multilayer perceptron neural network (MLPN), radial basis function neural network (RBFN), support vector machines (SVM), gene expression programming (GEP), and decision tree (DT) were constructed using the experimental toxicity data. Diversity and non-linearity in the chemicals’ data were tested using the Tanimoto similarity index and Brock–Dechert–Scheinkman statistics. Predictive and generalization abilities of various models constructed here were compared using several statistical parameters. PNN and GRNN models performed relatively better than MLPN, RBFN, SVM, GEP, and DT. Both in two and four category classifications, PNN yielded a considerably high accuracy of classification in training (95.85 percent and 90.07 percent) and validation data (91.30 percent and 86.96 percent), respectively. GRNN rendered a high correlation between the measured and model predicted −log LC 50 values both for the training (0.929) and validation (0.910) data and low prediction errors (RMSE) of 0.52 and 0.49 for two sets. Efficiency of the selected PNN and GRNN models in predicting acute toxicity of new chemicals was adequately validated using external datasets of different fish species (fathead minnow, bluegill, trout, and guppy). The PNN and GRNN models showed good predictive and generalization abilities and can be used as tools for predicting toxicities of structurally diverse chemical compounds.

Knowledge of the vomeronasal neuroepithelium (VNNE) microanatomy is disproportionately based on rodents. To broaden our knowledge, we examined olfactory marker protein (OMP) expression in a sample of twenty-three non-human primates. The density of OMP (+) vomeronasal sensory neurons (VSNs) in the VNNE was measured. Here we compared OMP (+) VSN density in five species of Saguinus (a genus of New World monkey) of different ages to a comparative primate sample that included representatives of every superfamily in which a VNO is postnatally present. In Saguinus spp., the VNNE at birth is thin, usually comprising one or two nuclear rows. At all ages studied, few VNNE cells are OMP reactive as view in coronal sections. In the comparative sample, the OMP (+) VSNs appear to be far more numerous in the spider monkey (another New World monkey) and the bushbaby (a distant relative). Other species (e.g., owl monkey) had a similar low density of OMP (+) VSNs as in Saguinus. These results expand our earlier finding that few VSNs are OMP (+) in Saguinus geoffroyi to other species of the genus. Our sample indicates that the number of OMP (+) VSNs in primates varies from ubiquitous to few with New World monkeys varying the most. The scarcity of OMP (+) cells in some primate VNOs reflects a lower number of terminally differentiated VSNs compared to a diverse range of mammals. If primates with relatively few OMP (+) VSNs have a functional vomeronasal system, OMP is not critical for stimulus detection.

Detailed reproductive pattern and associated endocrine characteristics have been documented in only a few species of order Chiroptera. The aim of the present study was to examine the changes in body weight, serum insulin, leptin, androstenedione and luteinizing hormone (LH) concentrations during annual ovarian cycle in the sheath-tailed bat, Taphozous longimanus. Bats were sampled over three years. Leptin, a satiety hormone produced primarily by adipose tissue, provides information to feeding center of the brain about nutritional status, fat mass, appetite and energy expenditure. The circulating concentration of leptin begins to increase from October and attains a peak in December. The peak serum leptin concentration coincides with body weight in November before winter dormancy in December. The serum leptin levels dissociate from body weight during December. The other peaks of serum leptin levels coincide with late stages of the two successive pregnancies. The serum insulin concentration begins to increase from September and attains a peak during December. The insulin concentration remains low from January to August. The circulating androstenedione concentration begins to increase in October, reaching a peak in December. This increase in androstenedione concentration correlated with the period of heavy accumulation of abdominal fat and increase in body weight. There was a sharp decline in androstenedione concentration and body weight in January. The serum LH shows peaks, in November, coinciding with the peaked body weight, the other peaks in January and May, coinciding with ovulation for the two successive pregnancies. The high leptin and insulin levels might be responsible for the maintenance of reproductive response and gonadal function during adverse environmental condition in the winter, while high androstenedione, and associated body weight along with LH might be responsible for maintaining basal gonadal function. We conclude that high leptin, androstenedione and insulin serve, as signal for the reproductive functions in that sufficient body fat are available to meet the caloric demands and maintain normal function during adverse winter conditions.

This study reports the levels and distribution patterns of some organochlorine pesticides (OCPs) in fish samples of the Gomti river, India, collected from three sites. In the fish muscles Sigma OCPs ranged between 2.58-22.56 ng g(-1) (mean value: 9.66 +/- 5.60 ng g(-1)). Neither spatial nor temporal trends could be observed in distribution of the OCPs. Aldrin was the predominant OCP, whereas, HCB and methoxychlor could not be detected. alpha-HCH and beta-HCH among the isomers of HCH and pp-DDE among the metabolites of DDT were the most frequently detected OCPs. The results revealed that the fish of the Gomti river are contaminated with various OCPs.

The vomeronasal organ (VNO) is known to be present in bats of the family Phyllostomidae, but in most species this is inferred from the presence of accessory olfactory bulbs. Like primates, bats have profound intergroup variations in the vomeronasal system. Of the family Phyllostomidae (49 genera, 143 species) the VNO of approximately 60 species has been studied. Here, we report light microscopic observations of the VNO of Anoura geoffroyi (fetus and adult), A. caudifer, and A. cultrata, as well as ultrastructural observations of the VNO in adult A. geoffroyi. The organ is crescent-shaped, with a wide lumen encroached by a "mushroom body" that contains a venous sinus. In adults, the vomeronasal cartilage is reduced, being longer in absolute length in fetal A. geoffroyi compared with the adult. In the neuroepithelium, the receptor cell microvilli are dark, distinct, and short, emerging from a vesicular tuft; the supporting cell microvilli are relatively much longer. Large paravomeronasal ganglia are observed. The receptor-free epithelium is undulating and lacks cilia or microvilli. Some characteristics of the VNO in Anoura have not been reported in other chiropterans to date, such as the marked reduction of the vomeronasal cartilage and absence of cilia in the receptor-free epithelium. Moreover, if A. geoffroyi is representative, the genus has an adult neuroepithelial volume similar to other mammals of its body size. Further examination of uninvestigated phyllostomid VNOs may elucidate a phylogenetic history of the family, as well as ecological or social correlates of the VNO in the order Chiroptera.

For nearly two decades, a database of brain structures from a large sample (272 species) of chiropterans has been widely accessible and used for socioecological analyses of mammals. However, this database remains incomplete since the hypophysis has not been measured. Since this glandular/neural structure has reproductive significance to chiropterans as for other mammals, this investigation was carried out using serial coronal sections of bat brains comprising the Heinz Stephan collection, Düsseldorf, Germany. Complete serially sectioned brains were examined in 313 individuals (165 species, 15 families). Using a well-documented method, hypophyseal volumes were determined from every fourth or sixth section in each individual. The strongest correlation was between body weight and the hypophysis (R(2) = 0.887) and its various components as well as between body weight and adenohypophysis (R(2) = 0.830) and neurohypophysis (R(2) = 0.925). Correlations were also strong for brain weight-adenohypophysis (R(2) = 0.817) and brain weight- neurohypophysis (R(2) = 0.911). Results indicated that: (1) in regression analyses, hipposiderids stand apart as having relatively large adenohypophysis; (2) analysis of residuals generated using least-squares regression of hypophyseal components suggests a trend among microchiropterans where females have a relatively larger adenohypophysis than males. However, this difference is only statistically significant in the largest samples: Phyllostomidae and Vespertilionidae. Pteropodids do not appear to follow this trend. Our findings suggest both phylogenetic and sexual differences in the adenohypophysis in particular, and indicate the need for investigation of larger samples by species, especially those best understood in reproductive and social biology.

In this study, structure-activity relationship (SAR) models have been established for qualitative and quantitative prediction of the blood-brain barrier (BBB) permeability of chemicals. The structural diversity of the chemicals and nonlinear structure in the data were tested. The predictive and generalization ability of the developed SAR models were tested through internal and external validation procedures. In complete data, the QSAR models rendered ternary classification accuracy of98.15%, while the quantitative SAR models yielded correlation (r(2)) of0.926 between the measured and the predicted BBB permeability values with the mean squared error (MSE)0.045. The proposed models were also applied to an external new in vitro data and yielded classification accuracy of82.7% and r(2)0.905 (MSE0.019). The sensitivity analysis revealed that topological polar surface area (TPSA) has the highest effect in qualitative and quantitative models for predicting the BBB permeability of chemicals. Moreover, these models showed predictive performance superior to those reported earlier in the literature. This demonstrates the appropriateness of the developed SAR models to reliably predict the BBB permeability of new chemicals, which can be used for initial screening of the molecules in the drug development process.

The nasolacrimal apparatus (NLA) is a multicomponent functional system comprised of multiple orbital glands (up to four larger multicellular exocrine structures), a nasal chemosensory structure (vomeronasal organ: VNO), and a connecting duct (nasolacrimal duct: NLD). Although this system has been described in all tetrapod vertebrate lineages, albeit not always with all three main components present, considerably less is known about its ontogeny. The Mongolian gerbil (Meriones unguiculatus) is a common lab rodent in which the individual components of the adult NLA have been well studied, but as yet nothing is known about the ontogeny of the NLA. In this study, serial sections of 15 fetal and three adult Mongolian gerbil heads show that the development of the NLA falls into three fetal stages: inception (origin of all features), elongation (lengthening of all features), and expansion (widening of all features). No postnatal or juvenile specimens were observed in this study, but considerable growth evidently occurs before the final adult condition is reached. The development of the orbital glands and the VNO in the Mongolian gerbil is largely consistent with those in other mammals, despite a slight nomenclatural conundrum for the anterior orbital glands. However, the Mongolian gerbil NLD follows a more circuitous route than in other tetrapods, due mainly to the convoluted arrangement of the narial cartilages, the development of a pair of enlarged incisors as well as an enlarged infraorbital foramen. The impact of these associated features on the ontogeny and phylogeny of the NLA could be examined through the approach of network science. This approach allows for the incorporation of adaptations to specific lifestyles as potential explanations for the variation observed in the NLA across different tetrapod clades.

The northern Indo-Gangetic alluvium region is known for intensive agricultural and industrial activities. Groundwater is the main source used for drinking, irrigation and industrial purposes in this region. Groundwater quality assessment is an essential component for its safer use. Thus, the measurements on various water quality parameters were carried out on surface water and groundwater samples of dug wells, bore wells and hand pumps at different sites spread over an area of about 2150 km(2). Influence of soil on hydrochemistry of groundwater was investigated through analyzing soil characteristics at selected sites in the region. Water quality classification was investigated through calculating the base-exchange, meteoric genesis, Langelier saturation and Ryznar stability indices. Groundwater sources were evaluated according to various criteria for their drinking and domestic, irrigation (salinity, chlorinity and sodicity), and industrial (saturation index) uses. Soil-water interactions and impact on groundwater quality was evaluated using ion flux coefficient (cf). Results of this study show that the groundwater in the study region is mainly of Na-HCO(3) and shallow meteoric water percolation type. Low cf values observed for NO(3), PO(4), Ca and metals indicate their lower mobility from soil matrix to groundwater. About 4-19% of the groundwater samples showed levels of TDS, hardness, alkalinity, Cl, F, SO(4), Ca, Mn, Pb, Cr and Fe above their respective permissible limits. Majority of samples violating the drinking water guidelines belong to shallow depth aquifer. Correlations between various parameters lead to interpretation of the results of analysis and suggesting the ionic species present in the groundwater sources. Contamination of some groundwater aquifers with F, Pb and Cr indicates natural and anthropogenic influences.

Callitrichid primates (tamarins, marmosets) have extreme variation in the vomeronasal organ (VNO), including ontogenetic differences in the neuroepithelium and vomeronasal duct (VND) patency at birth. Such differences render the timing and extent of VNO maturation debatable in callitrichids, but no studies have used neuron-specific immunohistochemical markers to address this question. The present study compared the number of VNO epithelial cells that express immunoreactivity to neuron-specific beta-tubulin III (BT), VNO length, and VNO cross-sectional area between two species of tamarins (Leontopithecus rosalia and Saguinus geoffroyi) that differed in perinatal VND patency. Neonatal lemurs and adult marmosets and bushbabies were also examined for a comparison to species previously shown to have a relatively large amount of VNO neuroepithelium and patent VNDs. The head of each specimen was serially sectioned in the coronal plane. Based on known rostrocaudal start/stop points of the VNO, selected unstained sections were used for BT protocols and area measurement at three percentiles (25th, 50th, 75th) in each specimen. Each section was photographed and enlarged for cell counts and measurement of cross-sectional epithelial area. In each specimen, the number of BT(+) cells in the VNO was counted at each percentile and expressed as a number per mm(2). Results indicated that lemur VNOs had a dense population of BT(+) cells at birth, but the VNO was more varied in the tamarin species. S. geoffroyi had few or no BT(+) cells in VNOs of neonates, which had fused VNDs, but had an increased BT(+) population by 1 and 2 months postnatal age, when the VND was patent. Of the species with patent VNDs at birth, neonatal L. rosalia had a denser population of BT(+) cells compared to S. geoffroyi, though not to the degree seen in neonatal lemurs or adult marmosets and bushbabies. These findings show that BT immunohistochemistry is a useful comparative method for the study of VNOs in subadult primates. Since the quantity of nonsensory VNO epithelium varies substantially between species, epithelial area measurements may be misleading, and BT(+) cell counts appeared to be the best quantitative method for comparing receptor neuron numbers among primates. It is suggested that the greater BT(+) cell population in L. rosalia at all subadult stages examined reveals an earlier maturation of the neuroepithelium compared to S. geoffroyi. Further investigation should consider whether this may relate to a comparatively brief subadult ontogeny and early onset of adult behaviors in L. rosalia compared to other tamarins studied to date.

The terms "microsmatic" and "macrosmatic" are used to compare species with greater versus lesser olfactory capabilities, such as carnivores compared to certain primates. These categories have been morphologically defined based on the size of olfactory bulb and surface area of olfactory epithelium in the nasal fossa. The present study examines assumptions regarding the morphological relationship of bony elements to the olfactory mucosa, the utility of olfactory epithelial surface area as a comparative measurement, and the utility of the microsmatic concept. We examined the distribution of olfactory neuroepithelium (OE) across the anteroposterior length of the nasal fossa (from the first completely enclosed cross-section of the nasal fossa to the choanae) in the microsmatic marmoset (Callithrix jacchus) compared to four species of nocturnal strepsirrhines (Otolemur crassicaudatus, O. garnetti, Microcebus murinus, and Cheirogaleus medius). Adults of all species were examined and infant C. jacchus, O. crassicaudatus, M. murinus, and C. medius were also examined. All specimens were serially sectioned in the coronal plane and prepared for light microscopic study. Distribution of OE across all the turbinals, nasal septal surfaces, and accessory spaces of the nasal chamber was recorded for each specimen. The right nasal fossae of one adult C. jacchus and one neonatal M. murinus were also three-dimensionally reconstructed using Scion Image software to reveal OE distribution. Findings showed OE to be distributed relatively more anteriorly in adult C. jacchus compared to strepsirrhines. It was also distributed more anteriorly along the nasal septal walls and recesses in neonates than adults. Our findings also showed that OE surface area was not a reliable proxy for receptor neuron numbers due to differing OE thickness among species. Such results indicate that nasal cavity morphology must be carefully reconsidered regarding traditional functional roles (olfaction versus air conditioning) assigned to various nasal cavity structures. At present, the microsmatic concept itself lacks a basis in nasal chamber morphology, since OE may have varying patterns of distribution among different primates.

Vomeronasal organ (VNO) morphology varies markedly across primate taxa. Old World monkeys display no postnatal VNO. Humans and at least some apes retain a vestigial VNO during postnatal life, whereas the strepsirrhines and New World Monkeys present a morphologically well-defined VNO that, in many species, is presumed to function as an olfactory organ. Available microanatomical and behavioral studies suggest that VNO function in these species does not precisely duplicate that described in other mammalian taxa. The questions of which species retain a functional VNO and what functions they serve require inquiry along diverse lines but, to be functional, the vomeronasal epithelium must be neuronal and olfactory. We used immunohistochemistry to establish these criteria in six primate species. We compared the expression of two neuronal markers, neuron-specific beta-tubulin (BT) and protein gene product 9.5, and olfactory marker protein (OMP), a marker of mature olfactory sensory neurons, in paraffin-embedded VNO sections from two strepsirrhine and four haplorhine species, all of which retain morphologically well-defined VNOs during postnatal life. The infant Eulemur mongoz, adult Otolemur crassicaudatus, neonatal Leontopithicus rosalia, and adult Callithrix jacchus express all three proteins in their well-defined vomeronasal neuroepithelia. The infant Tarsius syrichta showed some BT and OMP immunoreactivity. We establish that two strepsirrhine species and at least some New World haplorhines have mature sensory neurons in the VNO. In contrast, at all ages examined, Saguinus geoffroyi VNO expresses these markers in only a few cells.

Most studies on mammalian vomeronasal organ (VNO) have been on laboratory-bred animals. Our present study examines the VNO in wild-caught meadow voles (Microtus pennsylvanicus: n=16) and prairie voles (M. ochrogaster: n=15). These species vary in their mating strategies and degree of parental care by males. M. ochrogaster exhibits pair bonding and more paternal care compared to M. pennsylvanicus, a promiscuous species. We hypothesize that sexual dimorphism will occur in the promiscuous species based on previous studies which suggest that those who exhibit more aggressive or masculine behavior have larger VNOs. Our results support our original finding that VNOs are not different in size in wild Microtus spp. that vary in male parental tendencies. However, the present study also indicates that M. pennsylvanicus, the species exhibiting more disparate parental tendencies, exhibited larger VNOs in females than males. This is the reverse of previous findings on rats, and we hypothesize that this difference may be due to mate selectivity and/or maternal aggression.

Ecological explanations have been put forward to account for the precocious or delayed development of patency in ducts leading to the vomeronasal organ (VNO) in certain mammals. Perinatal function may be related, in part, to the patency or fusion of the vomeronasal and nasopalatine (NPD) ducts. However, few studies have focused on NPD development in primates, which generally have a prolonged period of dependence during infancy. In this study we examined 24 prenatal primates and 13 neonatal primates, and a comparative sample of fetal mice and insectivores. In embryonic and early fetal Microcebus murinus, the NPD was completely fused, whereas in fetuses of later stages the duct was partially fused or completely patent. M. myoxinus of all stages demonstrated some degree of NPD fusion. In all other prenatal primates, the NPD was fused to some extent. Four prenatal insectivores (Tenrec ecaudatus) showed some degree of NPD fusion. In Mus musculus at 19 days gestation, the NPD was patent, although the anatomically separate VNO duct was fused. T. ecaudatus and most of the neonatal primates revealed complete NPD patency. An exception was Saguinus geoffroyi, which exhibited fusion of the NPD near the VNO opening. These observations may relate to differences in perinatal VNO function. The differences noted in our study suggest that M. murinus and M. myoxinus may differ in perinatal VNO functionality and perhaps in related behavior. Observations of neonatal primates suggest that NPD patency may be relatively common at birth and could serve other purposes in addition to being an access route for VNO stimuli. Anat Rec Part A 274A:862–869, 2003. © 2003 Wiley-Liss, Inc.

It has been suggested that the variability of the primate vomeronasal organ (VNO) may be greater than previously thought, especially among New World monkeys. It is not clear to what extent VNO variation reflects ontogenetic, functional, or phylogenetic differences among primates. The present study investigated VNO anatomy in an ontogenetic series of two genera of callitrichid primates, in order to assess recent attempts to develop VNO character states and to examine the evidence for VNO functionality at different life stages. A sample of six Leontopithecus rosalia, one L. chrysomelas, and six Saguinus geoffroyi was serially sectioned and stained using various methods. Two adult Callithrix jacchus were also sectioned for comparative purposes. The VNO of each primate was examined by light microscopy along its entire rostrocaudal extent. VNOs of the tamarins were described to determine whether they fit into 1 of 3 character states recently attributed to various New World monkeys. At birth, the two species of tamarins differed in the nature of communication between the VNO and nasopalatine duct (NPD). Two of 3 neonatal S. geoffroyi exhibited a fused VNO duct in a more dorsal position (adjacent to the nasal cavity) compared to that of L. rosalia. The VNO duct communicated with the NPD and was patent in neonatal L. rosalia. Both species appeared to have an age-related increase in the amount of sensory epithelium in the VNO. Subadult L. rosalia had caudal regions of the VNO that were exceptionally well-developed, similar to those of strepsirhine primates. Compared to subadults, all adult callitrichids appeared to have more ventral communications of the VNO duct directly into the NPD. Adult S. geoffroyi and L. chrysomelas both had VNO sensory epithelium separated by multiple patches of nonsensory epithelium. This contrasted with the VNOs of C. jacchus, which had a nearly continuous distribution of receptors on all surfaces of the VNO. The findings indicate that tamarins have delayed maturation of the VNO epithelium, and that some species have little or no perinatal function. These results also suggest that ontogenetic changes in craniofacial form may alter the position of the VNO in tamarins. The present study supports the use of at least two character states to categorize the VNO of various callitrichids, but it is suggested that one of these, previously called "reduced sensory epithelium" should be instead termed "interrupted sensory epithelium." The distribution of VNO sensory epithelium does not appear to reflect phylogenetic influences; it is more likely a functional characteristic that varies throughout postnatal life. Therefore, this chemosensory system has a high degree of plasticity relating to age and function, which in some instances can confound the use of characteristics as phylogenetic traits. Further study is needed to quantify VNO receptors in various species to determine if functional differences exist and if some species have more precocious VNO function than others.

The vomeronasal organs (VNOs) of mammals are highly variable epithelial structures found bilaterally in the mucosa of the nasal septum. Whereas the discovery of the human VNO is traditionally ascribed to Frederick Ruysch (1703, 1724), the organ is named after Ludwig Levin Jacobson (1811, 1813) who described it in nonhuman mammals. We recently have pointed out controversies surrounding the incidence and structure of the enigmatic human VNO, and herein, we provide a historical analysis of its discovery. We present evidence that the honor of discovering the human VNO truly belongs to Kölliker (1877), and not to Ruysch. Ruysch illustrated the lateral view of a 2-year-old infant's nasal septum, and it is unclear whether the right nasal passage, the tubular VNO or its opening, or an unrelated duct is being indicated. Jacobson reported the VNO to be missing in humans. Its discovery in the human embryo can be related in part to later authors, such as Dursy (1869). Our reappraisal of the literature confirms that Kölliker was actually the first among these 18th-689th century investigators to provide evidence of the human VNO as a histologically identifiable structure in the fetus and the adult.

Humans and most of our closest extant relatives, the anthropoids, are notable for their reduced "snout." The striking reduction in facial projection is only a superficial similarity. All anthropoids, including those with long faces (e.g., baboons), have lost numerous internal projections (turbinals) and spaces (recesses). In sum, this equates to the loss of certain regions of olfactory mucosa in anthropoids. In addition, an accessory olfactory organ, the vomeronasal organ, is non-functional or even absent in all catarrhine primates (humans, apes, monkeys). In this commentary, we revisit the concept of anatomical reductions as it pertains to the anthropoid nasal region. Certain nasal structures and spaces in anthropoids exhibit well-known attributes of other known vestiges, such as variability in form or number. The cupular recess (a vestige of the olfactory recess) and some rudimentary ethmoturbinals constitute reduced structures that presumably were fully functional in our ancestors. Humans and at least some apes retain a vestige that is bereft of chemosensory function (while in catarrhine monkeys it is completely absent). However, the function of the vomeronasal system also includes prenatal roles, which may be common to most or all mammals. Notably, neurons migrate to the brain along vomeronasal and terminal nerve axons during embryogenesis. The time-specific role of the VNO raises the possibility that our concept of functional reduction is too static. The vomeronasal system of humans and other catarrhine primates appears to qualify as a "chronological" vestige, one which fulfills part of its function during ontogeny, and then becomes lost or vestigial.

The vomeronasal organ (VNO), also known as the Jacobson's organ, is a bilateral chemosensory organ found at the base of the nasal cavity specialized for the detection of higher-molecular weight (non-volatile) chemostimuli. It has been linked to pheromone detection. The VNO has been well studied in nocturnal lemurs and lorises, but poorly studied in diurnal/cathemeral species despite the large repertoire of olfactory behaviors noted in species such as Lemur catta. Here, the VNO and associated structures were studied microanatomically in one adult female and one adult male L. catta. Traditional and immunohistochemical procedures demonstrate the VNO epithelium consists of multiple rows of sensory neurons. Immunoreactivity to Growth-associated protein 43 (GAP43) indicates the VNO is postnatally neurogenic. In volume, the VNO neuroepithelium scales similarly to palatal length compared to nocturnal strepsirrhines. Numerous taste buds present at the oral opening to the nasopalatine duct, with which the VNO communicates, provide an additional (or alternative) explanation for the flehmen behavior that has been observed in this species. The VNO of L. catta is shown to be microanatomically comparable to that of nocturnal strepsirrhines. Like nocturnal strepsirrhines, the VNO of L. catta may be functional in the reception of high-molecular weight secretions.

The research aims to develop multispecies quantitative structure-activity relationships (QSARs) modeling tools capable of predicting the acute toxicity of diverse chemicals in various Organization for Economic Co-operation and Development (OECD) recommended test species of different trophic levels for regulatory toxicology. Accordingly, the ensemble learning (EL) approach based classification and regression QSAR models, such as decision treeboost (DTB) and decision tree forest (DTF) implementing stochastic gradient boosting and bagging algorithms were developed using the algae (P. subcapitata) experimental toxicity data for chemicals. The EL-QSAR models were successfully applied to predict toxicities of wide groups of chemicals in other test species including algae (S. obliguue), daphnia, fish, and bacteria. Structural diversity of the selected chemicals and those of the end-point toxicity data of five different test species were tested using the Tanimoto similarity index and Kruskal-Wallis (K-W) statistics. Predictive and generalization abilities of the constructed QSAR models were compared using statistical parameters. The developed QSAR models (DTB and DTF) yielded a considerably high classification accuracy in complete data of model building (algae) species (97.82%, 99.01%) and ranged between 92.50%-94.26% and 92.14%-94.12% in four test species, respectively, whereas regression QSAR models (DTB and DTF) rendered high correlation (R(2)) between the measured and model predicted toxicity end-point values and low mean-squared error in model building (algae) species (0.918, 0.15; 0.905, 0.21) and ranged between 0.575 and 0.672, 0.18-0.51 and 0.605-0.689 and 0.20-0.45 in four different test species. The developed QSAR models exhibited good predictive and generalization abilities in different test species of varied trophic levels and can be used for predicting the toxicities of new chemicals for screening and prioritization of chemicals for regulation.

Six pharmaceuticals of different categories, such as nonsteroidal anti-inflammatory drugs (ibuprofen, ketoprofen, naproxen, diclofenac), anti-epileptic (carbamazepine), and anti-microbial (trimethoprim), were investigated in wastewater of the urban areas of Ghaziabad and Lucknow, India. Samples were concentrated by solid phase extraction (SPE) and determined by high-performance liquid chromatography (HPLC) methods. The SPE-HPLC method was validated according to the International Conference on Harmonization guidelines. All the six drugs were detected in wastewater of Ghaziabad, whereas naproxen was not detected in Lucknow wastewater. Results suggest that levels of these detected drugs were relatively higher in Ghaziabad as compared to those in Lucknow, and diclofenac was the most frequently detected drug in both the study areas. Detection of these drugs in wastewater reflects the importance of wastewater inputs as a source of pharmaceuticals. In terms of the regional distribution of compounds in wastewater of two cities, higher spatial variations (coefficient of variation 112.90-459.44%) were found in the Lucknow wastewater due to poor water exchange ability. In contrast, lower spatial variation (162.38-303.77%) was observed in Ghaziabad. Statistical analysis results suggest that both data were highly skewed, and populations in two study areas were significantly different (p 0.05). A risk assessment based on the calculated risk quotient (RQ) in six different bioassays (bacteria, duckweed, algae, daphnia, rotifers, and fish) showed that the nonsteroidal anti-inflammatory drugs (NSAIDs) posed high (RQ1) risk to all the test species. The present study would contribute to the formulation of guidelines for regulation of such emerging pharmaceutical contaminants in the environment.

The vomeronasal organ (VNO) is a chemosensory organ that functions in sociosexual communication in many vertebrates. In strepsirhine primates and New World monkeys, the bilateral VNOs are traditionally understood to exist as a well-developed chemosensory epithelial unit. In contrast, the VNOs of catarrhine primates are thought to be absent or exist only as reduced epithelial tubes of uncertain function. However, the VNO of New World monkeys shows substantial variation in the extent of sensory epithelium. Recent findings that the chimpanzee (Pan troglodytes) possesses a VNO similar to humans suggest the variability of the VNO among haplorhine primates may be more extensive than previously thought, and perhaps more at par with that observed in chiropterans. The atypical histologic structure and location of the human/chimpanzee VNO suggest accessory glandular secretion and transport functions. Other catarrhine primates (e.g., Macaca spp.), may truly be characterized by VNO absence. Unique aspects of facial growth and development in catarrhine primates may influence the position or even presence of the VNO in adults. These recent findings demonstrate that previous investigations on some catarrhine primates may have missed the VNO and underestimated the extent of variability. As an understanding of this variation increases, our view of VNO functionality and associated terminology is changing. Further investigations are needed to consider phylogenetic implications of VNO variability and the association of craniofacial form and VNO anatomic position in primates. Anat Rec (New Anat) 265:176–192, 2001. © 2001 Wiley-Liss, Inc.

During the 20th century, the human vomeronasal organ (VNO) has been controversial regarding its structure, function, and even identity. Despite reports that provide evidence for its presence throughout prenatal and postnatal ontogeny, some studies and numerous textbooks declare its absence in late fetal and postnatal humans. To that end, the present study was designed to establish firmly whether the human VNO is homologous with that of other mammals and whether it degenerates (partially or completely) or persists throughout prenatal development. Fifty human embryos and fetuses (33 d to 32 wk fertilisation age) and 2 neonates were examined by light microscopy. Four embryonic primates (mouse lemurs) were examined for a comparison of VNO embryogenesis. The presence or absence and structural characteristics of the VNO and supporting tissues are described. The first appearance of the VNO was in the form of bilateral epithelial thickenings of the nasal septum, the vomeronasal primordium. The primordia invaginated between 37 and 43 d of age and formed the tubular VNO. The tubular VNO was located dorsally at a variable distance from, but was always spatially separated from the paraseptal cartilages. The mouse lemurs examined in this study and other reports from the literature indicate that the human VNO resembles that of primates having functional VNOs until just after a tubular VNO is formed. Examination of the VNO and adjacent tissues suggested that the VNO may lose receptor cells and corresponding vomeronasal nerves and become a ciliated, pseudostratified epithelium between approximately 12 and 14 wk of age. Our findings indicate the prenatal human VNO goes through 3 successive stages: early morphogenesis, transformation (of the epithelium), and growth. These observations indicated that (1) all embryonic humans develop a vomeronasal organ which is homologous with the VNOs of other mammals, but which has become displaced and highly variable in relative location during embryogenesis; (2) the human vomeronasal organ does not degenerate prenatally, but very likely loses the functional components of the vomeronasal complex of other mammals; and (3) the remnant of the human VNO persists until birth and beyond.

This study investigates the vomeronasal organ in extant nocturnal strepsirhines as a model for ancestral primates. Cadaveric samples from 10 strepsirhine species, ranging from fetal to adult ages, were studied histologically. Dimensions of structures in the vomeronasal complex, such as the vomeronasal neuroepithelium (VNNE) and vomeronasal cartilage (VNC) were measured in serial sections and selected specimens were studied immunohistochemically to determine physiological aspects of the vomeronasal sensory neurons (VSNs). Osteological features corresponding to vomeronasal structures were studied histologically and related to 3-D CT reconstructions. The VNC consistently rests in a depression on the palatal portion of the maxilla, which we refer to as the vomeronasal groove (VNG). Most age comparisons indicate that in adults VNNE is about twice the length compared with perinatal animals. In VNNE volume, adults are 2- to 3-fold larger compared with perinatal specimens. Across ages, a strong linear relationship exists between VNNE dimensions and body length, mass, and midfacial length. Results indicate that the VNNE of nocturnal strepsirhines is neurogenic postnatally based on GAP43 expression. In addition, based on Olfactory Marker Protein expression, terminally differentiated VSNs are present in the VNNE. Therefore, nocturnal strepsirhines have basic similarities to rodents in growth and maturational characteristics of VSNs. These results indicate that a functional vomeronasal system is likely present in all nocturnal strepsirhines. Finally, given that osteological features such as the VNG are visible on midfacial bones, primate fossils can be assessed to determine whether primate ancestors possessed a vomeronasal complex morphologically similar to that of modern nocturnal strepsirhines.

Background: Our initial observation of the macroscopically pigmented pineal gland of the big brown bat, Eptesicus fuscus, led to this study. Information has been lacking on pigmentation in the pineal and its significance in mammals in general and bats in particular. This report begins to address this situation. Methods: Bats were examined both in the wild and after exposure to various experimental conditions. The pineals were examined macroscopically as well as with light and electron microscopy. The pigment was identified as melanin by its color, the ultrastructure of its granules, and their reaction with hydrogen peroxide. Results: Gross observations showed the pineals to be variably pigmented, which were subjectively scored from unpigmented to heavily pigmented. Pineals from bats exposed to a continuous 24 h light regimen or those from a summer population contained very little, if any, externally visible melanin. Such pineals are considered unpigmented in this study. In contrast, pineals from 74% of 156 animals taken together, either subjected to constant darkness or hibernation (simulated or natural), exhibited very heavily pigmented pineals. The pigment in these cases even extended to the juxtapineal meningeal covering. The pineal was pigmented even in a newborn Eptesicus. Conclusions: The pineal pigmentation in the big brown bat appears to intensify with constant darkness and may vary seasonally. The observation of macroscopically pigmented pineals in some other bats (Myotis lucifugus, Pipistrellus subfiavus, and Lasiurus borealis) suggests that this phenomenon may be of taxonomic value for the family Vespertilionidae (Order Chiroptera). © 1994 Wiley-Liss, Inc.

Although all platyrrhine primates possess a vomeronasal organ (VNO), few species have been studied in detail. Here, we revisit the microanatomy of the VNO and related features in serially sectioned samples from 41 platyrrhine cadavers (14 species) of mixed age. Procedures to identify terminally differentiated vomeronasal sensory neurons (VSNs) via immunolabeling of olfactory marker protein (OMP) were used on selected specimens. The VNO varies from an elongated epithelial tube (e.g., Ateles fusciceps) to a dorsoventrally expanded sac (e.g., Saguinus spp.). The cartilage that surrounds the VNO is J-shaped or U-shaped in most species, and articulates with a groove on the bony palate. Preliminary results indicate a significant correlation between the length of this groove and length of the VNO neuroepithelium, indicating this feature may serve as a skeletal correlate. The VNO neuroepithelium could be identified in all adult primates except Alouatta, in which poor preservation prevented determination. The VNO of Ateles, described in detail for the first time, had several rows of VSNs and nerves in the surrounding lamina propria. Patterns of OMP-reactivity in the VNO of perinatal platyrrhines indicate that few or no terminally differentiated VSNs are present at birth, thus supporting the hypothesis that some platyrrhines may have delayed maturation of the VNO. From a functional perspective, all platyrrhines studied possess structures required for chemoreception (VSNs, vomeronasal nerves). However, some microanatomical findings, such as limited reactivity to OMP in some species, indicate that some lineages of New World monkeys may have a reduced or vestigial vomeronasal system.

The facial glands of bats are modified skin glands, whereas there are up to three different orbital glands: Harderian, lacrimal, and Meibomian glands. Scattered studies have described the lacrimal and Meibomian glands in a handful of bat species, but there is as yet no description of a Harderian gland in bats. In this study we examined serial sections of orbitofacial glands in eight families of bats. Much variation amongst species was observed, with few phylogenetic patterns emerging. Enlarged facial glands, either sudoriparous (five genera) or sebaceous (vespertilionids only) were observed. Meibomian and lacrimal glands were present in most species examined (except Antrozous), though the relative level of development varied. Two types of anterior orbital glands were distinguished: the Harderian gland (tubulo-acinar: observed in Rousettus, Atribeus, Desmodus and Miniopterus) and caruncular (sebaceous: observed in Eptesicus and Dieamus). The relative development of the nasolacrimal duct and the vomeronasal organ did not appear to be correlated with the development of any of the exocrine glands examined. There does, however, appear to be a correlation between the presence of at least one well developed exocrine gland and the level of communality and known olfactory acuity, best documented in Artibeus, Desmodus, and Miniopterus.

Pinealocytes are not only the principal cellular components of the pineal gland, but they are also the principal synthetic machinery of this enigmatical gland with highly diverse and often questionable empyreal roles assigned to it. Ultrastructural descriptions of pinealocytes belonging to some 70 species of mammals (a mere 2% or less of the over 4,200 mammalian species) have been summarized from the available literature with new observations on 12 species of chiropterans. Space limitation precluded any treatment of the supporting glia, neural elements, and the perivascular spaces. A detailed table lists nearly all mammalian species whose pineal ultrastructure has been investigated. Blanks in this table point to the necessity of studies on those particular groups. A tabular listing of unusual structures reported within the pinealocyte cytoplasm points out the impending experimental work on these species. Such studies using the latest techniques might provide clearer insights into the functional role of the pineal gland as an important and integral component of the neuroendocrine axis. Whereas sufficient structural information now exists on cytoplasmic organelles such as synaptic ribbons and spherules, annulate lamellae, subsurface cisterns, and the several types of synaptic arrangements seen in relation to the pinealocyte soma and its processes, the functional role of these structures in pineal synthetic processes remains to be elucidated.

The vampire bat, Desmodus rotundus, is exceptionally agile and stealthy in nature. Feeding at night on cattle blood, it is a known scourge carrying rabies. It is endowed with a very high neocortical volume among bats, acute olfactory capabilities and an accessory olfactory system. These characteristics have resulted into an impressive number of neuroanatomical investigations except a long due atlas on its brain. This study presents a cytoarchitectural atlas of the brain of the common vampire, Desmodus rotundus murinus, in the frontal plane, serially between the olfactory bulb and the medulla oblongata. Twenty six selected sections are presented, each separated by about 300 to 560 microns. The atlas figures show lugol fast blue-cresyl echt violet stained hemisections with their matching half in a labeled line drawing. About 595 discrete brain structures (some repeating) have been identified. This study is likely to provide the accurate localization of nuclear groups, whole structures, fiber tracts, and interconnections to facilitate future neuroanatomical and neurophysiological investigations on the vampire brain. O morcego vampiro, Desmodus rotundus, é excepcionalmente ágil e furtivo. Alimentando-se à noite do sangue de gado, é um conhecido flagelo portador da raiva. Entre os morcegos, apresenta um alto volume neocortical, capacidades olfatórias agudas e um sistema ofatório suplementar. Estas características têm suscitado um número impressionante de estudos neuroanatômicos, no entanto, não foi produzido ainda um atlas do cérebro desta espécie. O presente estudo apresenta, assim, um atlas citoarquitetural do cérebro do vampiro comum, Desmodus rotundus murinus, no plano frontal, serialmente entre o bulbo ofatório e a medula oblongata. Vinte e seis seções selecionadas são aqui apresentadas, cada uma separada por em torno de 300 a 560 mícrones. As figuras do atlas mostram hemisseções manchadas com lugol violeta de cresilo, com a sua respectiva metade apresentada numa figura rotulada. Em torno de 595 estruturas cerebrais discretas (algumas repetidas) foram identificadas. Este estudo proverá a localização precisa de grupos nucleares, estruturas inteiras, tratos de fibras, e interconexões para facilitar futuras investigações neuroanatômicas e neurofisiológicas realizadas no cérebro do morcego vampiro.

This study reports the concentration levels and distribution pattern of the persistent organochlorine pesticide (OCPs) residues in the water and bed-sediments of the Gomti River collected seasonally over a period of 2 years. The water and bed-sediment samples were collected from eight different sites and analyzed for aldrin, dieldrin, endrin, HCB, HCH isomers, DDT isomers/metabolites, endosulfan isomers (alpha and beta), endosulfan sulfate, heptachlor and its metabolites, alpha-chlordane, gamma-chlordane and methoxychlor. In the river water and sediments SigmaOCPs residues ranged between 2.16 and 567.49 ng l(-1) and 0.92 and 813.59 ng g(-1), respectively. The results, further, suggested that source of DDT contamination is from the aged and weathered agricultural soils with signature of recently used DDT in the river catchments. To assess any adverse effect of OCPs contamination on river's biological component, the threshold effect level (TEL) was used. The results revealed that bed-sediments of the Gomti River are contaminated with lindane, endrin, heptachlor epoxides and DDT, particularly at site-4 and may contribute to sediment toxicity in the freshwater ecosystem of the river.

Turbinals (scroll bones, turbinates) are projections from the lateral wall of the nasal fossa. These bones vary from simple folds to branching scrolls. Conventionally, maxilloturbinals comprise the respiratory turbinals, whereas nasoturbinals and ethmoturbinals comprise olfactory turbinals, denoting the primary type of mucosa that lines these conchae. However, the first ethmoturbinal (ETI) appears exceptional in the variability of it mucosal covering. Recently, it was suggested that the distribution of respiratory versus olfactory mucosae varies based on body size or age in strepsirrhine primates (lemurs and lorises). The present study was undertaken to determine how the rostrocaudal distribution of olfactory epithelium (OE) versus non-OE scales relative to palatal length in strepsirrhines. Serially sectioned heads of 20 strepsirrhines (10 neonates, 10 adults) were examined for presence of OE on ETI, rostral to its attachment to the nasal fossa wall (lateral root). Based on known distances between sections of ETI, the rostrocaudal length of OE was measured and compared to the length lined solely by non-OE (primarily respiratory epithelium). In 13 specimens, the total surface area of OE versus non-OE was calculated. Results show that the length of non-OE scales nearly isometrically with cranial length, while OE is more negatively allometric. In surface area, a lesser percentage of non-OE exists in smaller species than larger species and between neonates and adults. Such results are consistent with recent suggestions that the olfactory structures do not scale closely with body size, whereas respiratory structures (e.g., maxilloturbinals) may scale close to isometry. In primates and perhaps other mammals, variation in ETI morphology may reflect dual adaptations for olfaction and endothermy.

This study reports the levels and distribution patterns of selected polycyclic aromatic hydrocarbons (PAHs) in fish samples of the Gomti river, India, collected from three sites during the pre- and post-monsoon seasons of the years 2004-2005. In the fish muscles, SigmaPAHs ranged between 12.85 and 34.89 ng g(-1) wet wt (mean value: 23.98+/-6.70 ng g(-1)). Naphthalene was the most prevalent compound both in terms of detection as well as levels, while, benzo[k]fluoranthene, benzo(a)pyrene, and indeno(123-cd)pyrene + benzo(ghi)perylene could not be detected in any of the sample. Low-molecular weight PAHs were observed dominating over the high molecular weight PAHs.

Explanations for the chemosensory abilities of newborn mammals focus primarily on food (milk) acquisition and communication (e.g., maternal–infant bonding). However, the relative importance of the main and accessory (vomeronasal) olfactory systems is hypothesized to differ at birth between altricial and precocial mammals. Strepsirrhines (lemurs and lorises) possess main and accessory olfactory systems, and vary in life-history traits related to infant dependency and maturation. Accordingly, this study examines the size and maturational characteristics of vomeronasal (VNNE) and olfactory (OE) neuroepithelia in strepsirrhines. Serially sectioned heads of 18 infant cadavers were examined microscopically for neuroepithelial distribution. Measurements were taken on the length of the nasal fossa on one side that was occupied by VNNE and OE. The data were corrected for body size using the cranial length or body mass, and were then examined for correlation with several life-history variables, as well as activity pattern. In addition, immunohistochemistry was used to identify cells in the VNNE and OE that express olfactory marker protein (OMP), a marker of mature olfactory neurons. Relative OE extent was not significantly correlated with any of the life-history variables. Relative VNNE length was negatively correlated with relative gestation length and relative neonatal mass (P

The naked mole-rat (Heterocephalus glaber) is unusual in numerous life history characteristics as well as its eusocial organization. This species demonstrates widespread sexual suppression and prominent scent marking, behaviors that have been associated with pheromonal communication involving the vomeronasal organ in other rodents. Yet, previous studies indicate that urinary signals do not mediate sexual suppression in Heterocephalus. Surprisingly, no previous studies have examined the vomeronasal organ in this species. Here, we show that Heterocephalus is unique among rodents in showing no evidence of postnatal volumetric growth in the vomeronasal neuroepithelium. Subadults from birth to weaning fell within the same volume range as adults regardless of breeding/non-breeding status of the latter. A comparison of existing ontogenetic data on other mammals suggests that the proportionally small VNOs of Heterocephalus may be explained by a deficiency in VNNE growth. Growth deficiency of the vomeronasal organ in Heterocephalus may relate to a diminished role that pheromones play in certain social interactions for this species, such as breeding suppression. In light of the unique aspects of the vomeronasal organ in Heterocephalus, comparative studies of rodents may provide a model for understanding variation of this sensory system in other mammalian orders including primates, an order which shows a range from vestigial to demonstrably functional vomeronasal organs.