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A 40‐year old female chimpanzee (Pan troglodytes) developed hyporexia, weight loss, followed by progressive and complete blindness. Tomography demonstrated an intracranial mass in the rostroventral brain involving the optic chiasm, with a presumptive diagnosis of neoplasm. However, histopathology revealed a granulomatous meningoencephalitis, and tissue samples tested positive for Mycobacterium tuberculosis. [ABSTRACT FROM AUTHOR]

A senile male black capuchin monkey (Sapajus nigritus) kept under human care in a Zoo was found dead after 2 weeks presenting signals of weight loss and hyporexia. Histopathological revealed a necrotizing encephalitis. Although it was not observed microscopically, Sarcocystis sp infection was detected in brain tissue from molecular assays. These infections have been rarely described in neotropical primates, particularly associated with tissue lesions. [ABSTRACT FROM AUTHOR]

Summary: Artificial Intelligence (AI) carries the potential for unprecedented disruption in radiology, with possible positive and negative consequences. The integration of AI in radiology holds the potential to revolutionize healthcare practices by advancing diagnosis, quantification, and management of multiple medical conditions. Nevertheless, the ever‐growing availability of AI tools in radiology highlights an increasing need to critically evaluate claims for its utility and to differentiate safe product offerings from potentially harmful, or fundamentally unhelpful ones. This multi‐society paper, presenting the views of Radiology Societies in the USA, Canada, Europe, Australia, and New Zealand, defines the potential practical problems and ethical issues surrounding the incorporation of AI into radiological practice. In addition to delineating the main points of concern that developers, regulators, and purchasers of AI tools should consider prior to their introduction into clinical practice, this statement also suggests methods to monitor their stability and safety in clinical use, and their suitability for possible autonomous function. This statement is intended to serve as a useful summary of the practical issues which should be considered by all parties involved in the development of radiology AI resources, and their implementation as clinical tools. [ABSTRACT FROM AUTHOR]

Background: Identifying hereditary parkinsonism is valuable for diagnosis, genetic counseling, patient prioritization in trials, and studying the disease for personalized therapies. However, most studies were conducted in Europeans, and limited data exist on admixed populations like those from Latin America. Objectives: This study aims to assess the frequency and distribution of genetic parkinsonism in Latin America. Methods: We conducted a systematic review and meta‐analysis of the frequency of parkinsonian syndromes associated with genetic pathogenic variants in Latin America. We defined hereditary parkinsonism as those caused by the genes outlined by the MDS Nomenclature of Genetic Movement Disorders and heterozygous carriers of GBA1 pathogenic variants. A systematic search was conducted in PubMed, Web of Science, Embase, and LILACS in August 2022. Researchers reviewed titles and abstracts, and disagreements were resolved by a third researcher. After this screening, five researchers reanalyzed the selection criteria and extracted information based on the full paper. The frequency for each parkinsonism‐related gene was determined by the presence of pathogenic/likely pathogenic variants among screened patients. Cochran's Q and I2 tests were used to quantify heterogeneity. Meta‐regression, publication bias tests, and sensitivity analysis regarding study quality were also used for LRRK2‐, PRKN‐, and GBA1‐related papers. Results: We included 73 studies involving 3014 screened studies from 16 countries. Among 7668 Latin American patients, pathogenic variants were found in 19 different genes. The frequency of the pathogenic variants in LRRK2 was 1.38% (95% confidence interval [CI]: 0.52–2.57), PRKN was 1.16% (95% CI: 0.08–3.05), and GBA1 was 4.17% (95% CI: 2.57–6.08). For all meta‐analysis, heterogeneity was high and publication bias tests were negative, except for PRKN, which was contradictory. Information on the number of pathogenic variants in the other genes is further presented in the text. Conclusions: This study provides insights into hereditary and GBA1‐related parkinsonism in Latin America. Lower GBA1 frequencies compared to European/North American cohorts may result from limited access to gene sequencing. Further research is vital for regional prevalence understanding, enabling personalized care and therapies. © 2023 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society. [ABSTRACT FROM AUTHOR]

Background: Cancer is a well‐known risk factor for venous thromboembolism (VTE). A combined strategy of D‐dimer testing and clinical pre‐test probability is usually used to exclude VTE. However, its effectiveness is diminished in cancer patients due to reduced specificity, ultimately leading to a decreased clinical utility. This review article seeks to provide a comprehensive summary of how to interpret D‐dimer testing in cancer patients. Methods: In accordance with PRISMA standards, literature pertaining to the diagnostic and prognostic significance of D‐dimer testing in cancer patients was carefully chosen from reputable sources such as PubMed and the Cochrane databases. Results: D‐dimers have not only a diagnostic value in ruling out VTE but can also serve as an aid for rule‐in if their values exceed 10‐times the upper limit of normal. This threshold allows a diagnosis of VTE in cancer patients with a positive predictive value of more than 80%. Moreover, elevated D‐dimers carry important prognostic information and are associated with VTE reoccurrence. A gradual increase in risk for all‐cause death suggests that VTE is also an indicator of biologically more aggressive cancer types and advanced cancer stages. Considering the lack of standardization for D‐dimer assays, it is essential for clinicians to carefully consider the variations in assay performance and the specific test characteristics of their institution. Conclusions: Standardizing D‐dimer assays and developing modified pretest probability models specifically for cancer patients, along with adjusted cut‐off values for D‐dimer testing, could significantly enhance the accuracy and effectiveness of VTE diagnosis in this population. [ABSTRACT FROM AUTHOR]

Chylothorax is the accumulation of lymph in the thoracic cavity, and it has never been reported in neotropical primates. An emperor tamarin died and at necropsy chylothorax associated with pulmonary compressive atelectasis was diagnosed. Idiopathic chylothorax can be a cause of respiratory insufficiency and death in tamarins. [ABSTRACT FROM AUTHOR]

This is a case of lethal acute diarrhea associated with a mild neutrophilic enteritis in a buffy‐tufted‐ear marmoset (Callithrix aurita) with detection of A/B toxins and isolation of a toxigenic clade 3 Clostridioides difficile strain (A+B+CDT+, ST5), which should be considered as a potential cause of enteritis in this species. [ABSTRACT FROM AUTHOR]

Mammaliicoccus (Staphylococcus) sciuri has been rarely associated with infections and sepsis in humans. A 3‐month‐old male western lowland gorilla (Gorilla gorilla gorilla), born under human care, died after a traumatic event. Histologic, microbiologic, and molecular findings in postmortem demonstrated a suppurative meningoencephalitis and bacteremia associated with M. sciuri infection. [ABSTRACT FROM AUTHOR]

A 12‐year‐old female captive jaguar (Panthera onca) developed sudden severe respiratory distress and died close to the onset of clinical signs. The animal underwent mastectomy to remove neoplasms in the mammary glands 2 years prior to death. During the post‐mortem examination, multiple nodules were found in the remaining left inguinal mammary glands. Similar lesions were found in other organs. Microscopically, neoplasms were characterised by a tubulopapillary pattern with papillary projections into the central lumen of newly formed tubules (tubulopapillary mammary carcinoma). Immunohistochemistry (IHC) for oestrogen receptor, progesterone receptor and high molecular weight cytokeratin on the mammary tissue site and a metastatic site was performed with positive results. IHC for Ki‐67 was performed in the mammary lesion with positive labelling in 50% of the cells. In captive felids, malignant neoplasms may be aggressive with limited therapeutic options. Thus, attention is needed in anticipating arising tumours to support the use of control therapies and the long‐term preservation of captive jaguars. [ABSTRACT FROM AUTHOR]

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Background: Acanthocephalosis is an important cause of death in captive New World primates (NWP). Once established in a colony, it is extremely difficult to treat and control, quickly spreading among NWP with a high mortality rate. This study aimed to characterize the disease associated with infection with acanthocephalans according to its epidemiological, clinical, and anatomopathological aspects in a captive NWP population. Methods: From 2010 to 2020, a Brazilian zoo had recurrent deaths of NWP associated to acanthocephalan parasitism. Clinical and pathological profiles of these animals were analyzed considering the host species, sex, age, weight, clinical signs, therapeutic protocols, and pathological findings. Results: A total of 27 deaths associated with acanthocephalosis were recorded, all lethal cases affected tamarins and lion tamarins, corresponding to 67.5% of total deaths during the course of this study. Ten animals died with no previously detected clinical signs, whereas cases with noticeable clinical signs often had apathy and progressive weight loss, resulting in cachexia. Symptomatic NWP were treated with anthelmintic protocols, antibiotics, and support therapy. However, all hospitalized animals died and had grossly detectable adult acanthocephalans in the intestinal lumen that were identified as Prosthenorchis sp., which were associated with transmural and ulcerative enteritis. Conclusions: This report revealed the impact of acanthocephalosis in a naturally infected captive colony of NWP, particularly affecting tamarins (Saguinus spp.) and lion tamarins (Leontopithecus spp.), with failed treatment and control strategies. [ABSTRACT FROM AUTHOR]

Aim: To assess the relative importance of wind intensity and direction in explaining wetland invertebrate metacommunity organization. Location: Seventy‐eight wetland ponds in Patagonia (Argentina) covering a study area of 3.5 × 105 km2. Time period: Ponds were sampled once between 2006 and 2014. Major taxa studied: One hundred and fifty‐eight taxa of wetland aquatic invertebrates. Methods: We generated two beta diversity matrices (based on flying and non‐flying invertebrates) and six predictor matrices, including three environmental distance matrices, a topographic distance between ponds, and two wind pairwise matrices differing in wind speed. Using Moran spectral randomization of Mantel (MSR‐Mantel) tests (which account for spatial autocorrelation), we assessed the relationship between the response and the predictor matrices. We used a network‐constrained version of the nestedness metric based on overlap and decreasing fill (NODF), to assess if wind anisotropy (i.e., direction‐dependent) affected community nestedness among ponds. Results: Flying dispersers' dissimilarity was significantly explained by environmental variables, whereas non‐flying invertebrates' dissimilarity was not significantly explained by any of the distances tested. When wind direction was ignored, wind speed had a negligible effect on both types of communities, whereas when it was considered a consistent nested pattern emerged, with the eastern ponds (downwind) communities being subsets of those from the western ponds (upwind). Main conclusions: We found that the invertebrate communities were mainly assembled by a combination of environmental factors and wind directionality, although this depended on the dispersal ability of the organisms. [ABSTRACT FROM AUTHOR]

Biological forms occupy a constrained portion of theoretical morphospaces. Developmental models accounting for empirical morphospaces are necessary to achieve a better understanding of this phenomenon. We analyzed the phalangeal formulas (PFs) in lizards and relatives' hands by comparing them with a set of simulated PFs that compose a theoretical morphospace. We detected that: (1) the empirical morphospace is severely limited in size, (2) the PFs comply with two properties of phalangeal count per digit, namely the ordering rule (DI ≤ DII ≤ DIII ≤ DIV ≥ DV), and the contiguity relationship (neighbor digits differ on average in one phalanx), (3) the totality of the PFs can be categorized into four categories of hands aligned along a feasibility gradient. We also reconstructed the evolution of PFs and found a stepwise trajectory from the plesiomorphic PF towards reduced conditions. Finally, we propose a developmental model as the generative mechanism behind the PFs. It is consistent with the bulk of evidence managed and involves an ordered digit primordia initialization timed with periodic signals of joint formation coming from digit tips. Our approach is also useful to address the study of other meristic sequences in nature such as dental, floral, and branchial formulas. Highlights: Phalangeal formulas (PF) of Lepidosauria are a tiny fraction of the theoretical ones. We discover numerical patterns behind the observed set of PF in Lepidosaurians. We outline a dynamic evo‐devo model of hand formations accounting for such patterns. [ABSTRACT FROM AUTHOR]

Aim: South America is considered a biologically hybrid continent. To the south, the Patagonian region harbours a unique biota strongly related to other southern continents. To the northern portion, tropical and subtropical areas from the Neotropical region show a more complex taxocoenosis related to the Nearctic and Afro‐Oriental regions. The South American Transition Zone (STZ) has been proposed to belong simultaneously to both regions. This work aimed to test the validity of STZ in the light of the distributions of an ancient freshwater taxon. Location: South America. Taxon: Ephemeroptera. Methods: We compiled a dataset including all mayfly species having at least one record in South America (8,268 records for 661 species). By using the Network Analysis Method (NAM), we analysed the validity and delimitation of the STZ. Results: The distributions of Ephemeroptera give rise to groups of cohesively sympatric species with a clear distinction between Patagonian and Neotropical regions. Although some degree of overlap occurs between them, the overlapping area does not match the STZ to a significant extent. The units of co‐occurring species recovered show that Neotropical groups mainly occupy the STZ. Main conclusions: Almost the entire provinces of Puna, Desert and Paramo are not supported as part of the STZ by mayfly distribution. The transition zone between Patagonian and Neotropical mayfly fauna involves Southern Puna and high Andes (south to 17° S latitude), Monte province, and a narrow portion of Patagonian steppe with Chubut River being the southern limit. [ABSTRACT FROM AUTHOR]

Aim: To evaluate the structure of bird communities throughout the South American Gran Chaco determining the effects of climate, geography and land use/land cover in bird beta diversity, as well as to understand the beta diversity processes underlying land use changes across broad spatial ranges. Location: South American Gran Chaco. Taxon: Birds. Methods: We constructed a site‐by‐species matrix with occurrence probabilities of 293 bird species across 2,669 spatial units tiling completely the study area. Based on this matrix, we calculated pairwise dissimilarities scores and performed a hierarchical cluster analysis for describing the spatial configuration of dissimilarities. The clustering result was spatially represented through an original venation map with boundaries between sites widened in the function of their distance in the dendrogram. We used the Generalized Dissimilarity Modelling approach to model beta diversity, using geographic distance, climatic and land use/land cover information as predictors. We mapped beta diversity patterns using colour theory and the HSV colour model. Results: We identified two main clusters of sites across the Gran Chaco, which represent environmentally different sites and harbour very distinct assemblages of species. These main groups are separated by two natural delimiters: The Bermejo‐Pilcomayo interfluvium and the Lower Paraná floodplain. Overall, we observed that the percentage of cropland and climatic variables were important shapers of bird beta diversity. Main conclusions: We provide the first area‐wide assessment of land use/land cover effects on bird beta diversity for the Gran Chaco. The distribution of croplands has a marked influence on bird beta diversity at regional scale highlighting the role of anthropic changes in reshaping bird beta diversity within the ecoregion. Taking into account the global increasing conversion of forests into croplands, a growing footprint of land use changes over geographical patterns of bird diversity in forest biomes can be anticipated. [ABSTRACT FROM AUTHOR]

Background and aims: Deciding when to repeat and when to stop transarterial chemoembolization (TACE) in patients with hepatocellular carcinoma (HCC) can be difficult even for experienced investigators. Our aim was to develop a survival prediction model for such patients undergoing TACE using novel machine learning algorithms and to compare it to conventional prediction scores, ART, ABCR and SNACOR. Methods: For this retrospective analysis, 282 patients who underwent TACE for HCC at our tertiary referral centre between January 2005 and December 2017 were included in the final analysis. We built an artificial neural network (ANN) including all parameters used by the aforementioned risk scores and other clinically meaningful parameters. Following an 80:20 split, the first 225 patients were used for training; the more recently treated 20% were used for validation. Results: The ANN had a promising performance at predicting 1‐year survival, with an area under the ROC curve (AUC) of 0.77 ± 0.13. Internal validation yielded an AUC of 0.83 ± 0.06, a positive predictive value of 87.5% and a negative predictive value of 68.0%. The sensitivity was 77.8% and specificity 81.0%. In a head‐to‐head comparison, the ANN outperformed the aforementioned scoring systems, which yielded lower AUCs (SNACOR 0.73 ± 0.07, ABCR 0.70 ± 0.07 and ART 0.54 ± 0.08). This difference reached significance for ART (P <.001); for ABCR and SNACOR significance was not reached (P =.143 and P =.201). Conclusions: Artificial neural networks could be better at predicting patient survival after TACE for HCC than traditional scoring systems. Once established, such prediction models could easily be deployed in clinical routine and help determine optimal patient care. [ABSTRACT FROM AUTHOR]

Contents: The information of twin pregnancy frequencies in buffaloes is scarce in the literature. Evidence even indicates that twin pregnancies are not carried to term, but it does not seem to be the case. In this case report, the event of twin pregnancy in buffaloes is reported as well as its frequency. Twin birth is the presence of two or more embryos in a single gestation. Multiple births are uncommon in buffaloes since the species is uniparous. We studied a population of Murrah buffaloes in which slightly more than 13,000 births were observed. In this study, the frequency of occurrence of twin births in Murrah buffaloes was 0.14%. This low incidence impaired the estimation of genetic parameters. Twins can have advantages and disadvantages depending on the production system, which are discussed in this case report. [ABSTRACT FROM AUTHOR]

Contents: The objective of this study was to evaluate the genotype–environment interaction effect on age at first calving in buffaloes. The records were analysed using two approaches: (a) standard animal model and (b) reaction norm model. For the reaction norm analysis, two environmental gradients were formed, using age of first calving or milk yield group contemporary average. The results showed differences in the heritability estimates when using the two approaches. The reaction norm model indicated high heritability in more favourable environments and low magnitude genetic correlations between extreme environments. Based on our findings, we verified the significance of the genotype–environment interaction effect on age at first calving in buffaloes. [ABSTRACT FROM AUTHOR]

Background & Aims: Portal vein tumour thrombosis (PVTT) has a significant impact on the prognosis of patients with hepatocellular carcinoma (HCC). The degree of PVTT varies from sub‐/segmental invasion to complete occlusion of the main trunk. Aim of this study was to evaluate whether the degree of PVTT correlates with prognosis. Methods: A total of 1317 patients with HCC treated at our tertiary referral centre between January 2005 and December 2016 were included. PVTT was diagnosed by contrast‐enhanced computed tomography or magnetic resonance imaging. The extent of PVTT was documented according to the Liver Cancer Study Group of Japan classification: Vp0 = no PVTT, Vp1 = segmental portal vein invasion, Vp2 = right anterior/posterior portal vein, Vp3 = right/left portal vein and Vp4 = main trunk. Median overall survival (OS) was calculated for each group. Results: Portal vein tumour thrombosis was present in 484 (36.8%) patients. Median OS without PVTT was 35.7 months, significantly longer than in patients with PVTT (7.2 months, P < 0.001). The patients with PVTT were subclassified as follows: 103 Vp1, 87 Vp2, 143 Vp3 and 151 Vp4. The corresponding median OS yielded 14.6, 9.4, 5.8 and 4.8 months for Vp1‐Vp4, respectively (P < 0.001). Conclusions: Portal vein tumour thrombosis in patients with HCC is associated with a dismal prognosis. The results indicate an association between the extent of PVTT and OS. However, the extent of PVTT is not that decisive, as even minor PVTT leads to a very poor prognosis. Therefore, meticulous evaluation of cross‐sectional imaging is crucial for the clinical management of patients with HCC. [ABSTRACT FROM AUTHOR]

Significant technical advances have been made in radiology since the first discovery of X‐rays. Diagnostic techniques have become more and more complex, workflows have been digitized, and data production has increased exponentially. However, the radiology report as the main method for communicating examination results has largely remained unchanged. Growing evidence supports that more structured radiology reports offer various benefits over conventional narrative reports. Various efforts have been made to further develop and promote structured reporting. However, regardless of the potential benefits, structured reporting has still not seen widespread implementation into the clinical routine. With recent technical advances, especially new research topics such as big data and machine learning, structured reporting could prove essential for the future of radiology. New interoperable solutions are needed to facilitate the implementation of template‐based structured reporting into the clinical routine. Significant technical advances have been made in radiology, but the radiology report as the main method for communicating examination results has largely remained unchanged. Growing evidence supports that more structured radiology reports offer various benefits over conventional narrative. This article gives a brief overview regarding structured reporting in clinical radiology practice, and describes how to potentially implement it and the benefits it could hold. [ABSTRACT FROM AUTHOR]

Abstract: Aim: Traditionally, South American aquatic insects have been divided into cold and warm adapted forms. Cold‐adapted forms inhabit freshwater systems from higher latitudes, or higher altitudes even around the Equator. Warm‐adapted groups are defined as those found in lower latitudes and altitudes. This work aims to answer the questions: Are mayfly assemblages geographically segregated according to geographical (latitude) and topographical (altitude) surrogates of temperature? If so, where is this transition located? Location: South America. Methods: We compiled a data set about the relative incidence of 52 mayfly genera in 326 sampled communities. They span from 0 to 4,320 m and from 47.77° S to 5.74° N latitude. By virtue of the compositional nature of the data set, we applied the statistical procedures behind the Aitchison compositional data analysis. We delimited groups of assemblages based on their Aitchison distances and projected the data points onto a biplot obtained through Principal Component Analysis adjusted to compositions (Aitchison PCA). Results: A strong correspondence among biological and geographical information was detected, with mayfly assemblages clearly segregated in space. Andesiops and Meridialaris are typical cold‐adapted forms; Baetodes, Leptohyphes and Thraulodes represent the warm group. Thermal groups can be separated by a curved line of altitude in function of latitude expressed in terms of a superellipse arc. Main conclusions: The classical ecological bipartition of mayflies into warm and cold freshwater groups is formalized quantitatively. The dividing line between warm and cold assemblages levels off at high altitudes (c. 3,300 m) around the Equator and falls to sea level at southern latitudes. The community bipartition line is useful for tracking global change through records of altitudinal displacement below and above of the warm/cold line of involved ecological groups. [ABSTRACT FROM AUTHOR]

Aim To study the relationships between Uruguay and neighbouring geographical areas based on distributions of Ephemeroptera species (mayflies: an ancient order of aquatic insects). We wanted to evaluate whether Uruguay more closely represents (1) the southern limit of the tropical (Paranense and Amazonian) fauna or (2) the northern limit of the temperate (Pampean-Bonaerense) fauna. Location South America with an emphasis on Uruguay. Methods We compiled more than 5000 collection records of mayfly species throughout South America and evaluated these using current taxonomy and geographical validity. We used the Network Analysis Method ( NAM) on these data to identify units of co-occurrence ( UCs: mutually exclusive groups of co-distributed species, with each group connected through strong links of sympatry and disconnected from the others). We focused solely on those UCs that included Uruguay in their spatial ranges and used these to infer the vicinity relationships. Results We recovered four UCs consisting of many species that link Uruguay with tropical areas of Brazil and NE Argentina. These groups followed a geographically nested pattern. The results contradict the previously held view that the Uruguayan fauna holds strong affinities to that of temperate grasslands that lie to the south in central oriental Argentina (i.e. the currently accepted concept of Pampas). A comparison of the genera known from Uruguay and Buenos Aires Province further reinforces the distinction between Uruguay and temperate areas to the south. Main conclusions The hypothesis that Uruguay represents the southern limit of tropical affinities is strongly supported by mayfly distributions, indicating that a reappraisal of the Pampas as a cohesive biogeographical province is needed. We suggest that Uruguay and Buenos Aires should belong to different provinces, the former aligned with tropical provinces and the latter aligned with more temperate areas. [ABSTRACT FROM AUTHOR]

Sigmodontine rats are one of the most diverse components of the Neotropical mammal fauna. They exhibit a wide ecological diversity and a variety of locomotor types that allow them to occupy different environments. To explore the relationship between morphology and locomotor types, we analyzed traits of the postcranial osteology (axial and appendicular skeletons) of 329 specimens belonging to 51 species and 29 genera of sigmodontines exhibiting different locomotor types. In this work, postcranial skeletal characters of these rats are considered in an ecomorphological study for the first time. Statistical analyses showed that of the 34 osteological characters considered, 15 were related to the locomotor types studied, except for ambulatory. However, character mapping showed that climbing and jumping sigmodontines are the only taxa exhibiting clear adaptations in their postcranial osteology, which are highly consistent with the tendencies described in many other mammal taxa. Climbing, digging and swimming rats presented statistically differences in traits associated with their vertebral column and limbs, whereas jumping rats showed modifications associated with all the skeletal regions. Our data suggest that sigmodontine rats retain an all-purpose morphology that allows them to use a variety of habitats. This versatility is particularly important when considering the lack of specialization of sigmodontines for a specific locomotor mode. Another possible interpretation is that our dataset probably did not consider relevant information about these groups and should be increased with other types of characters (e.g. characters from the external morphology, myology, etc.). [ABSTRACT FROM AUTHOR]

An indirect method for the georeferencing of 3D point clouds obtained with terrestrial laser scanning ( TLS) data using control lines is presented. This technique could be used for rapid data acquisition where resources do not permit the use of expensive navigation sensors or the placement of pre-signalised targets. The most important characteristic is the development of a mathematical model based on the principle that the direction vector of the TLS straight line is coplanar with the plane defined by the origin of the TLS system, one endpoint of a control line and the direction vector of the control line in the ground reference coordinate system. The transformation parameters are estimated by minimising the distance between the control lines and their corresponding TLS straight lines. The proposed method was tested using both simulated and real data, and the advantages of this new approach are compared with conventional surveying methods. [ABSTRACT FROM AUTHOR]

Cytochrome bc1 complex is a crucial element in the mitochondrial respiratory chain, being indispensable for the survival of several species of Plasmodia that cause malaria and, therefore, it is a promising target for antimalarial drug development. We report a molecular docking study building on the most recently obtained X-ray structure of the Saccharomyces cerevisiae bc1 complex (PDB code: 3CX5) using several reported inhibitors with experimentally determined IC50 values against the Plasmodium falciparum bc1 complex. We produced a molecular docking model that correlated the calculated binding free energy with the experimental inhibitory activity of each compound. This Qo model was used to search the drug-like database included in the MOE package for novel potential bc1 complex inhibitors. Twenty three compounds were chosen to be tested for their antimalarial activity and four of these compounds demonstrated activity against the chloroquine-resistant W2 strain of P. falciparum. The most active compounds were also active against the atovaquone-resistant P. falciparum FCR3 strain and S. cerevisiae. Our study suggests the validity of the yeast bc1 complex structure as a model for the discovery of new antimalarial hits. [ABSTRACT FROM AUTHOR]

This paper focuses on the importance of the intermediate linker sequence for the stabilization of the cytoplasmic portion of murine P-glycoprotein, an ABC transporter involved in Multidrug Resistance (MDR) in cancer. Three putative protein-protein interaction areas were predicted to exist, two of them next to the C-terminal nucleotide-binding domain (NBD2) and the third one next to the inner leaflet interface of the lipid bilayer. These contact spots were confirmed by detailed contact maps from structures obtained before and after a 100 ns molecular dynamics production run, allowing a more thorough characterization of the type and number of residues involved in protein-protein contacts. It was found that these contact surfaces are located next to several highly conserved motifs of ABC transporters, serving as anchor points and assisting the linker's 'damper' function. [ABSTRACT FROM AUTHOR]

Cytochrome bc is a validated drug target of Plasmodium falciparum, the parasite that causes the most lethal form of malaria. The inhibition of cytochrome bc leads to the shutdown of the mitochondrial metabolism and the consequent arrest of pyrimidine biosynthesis essential for parasite development. Aiming to rationalize the stereoelectronic properties and extend the knowledge on a novel series of 4-pyridonimines guiding the search of antimalarial drugs, we carried out an extensive DFT comparative characterization. Results show electronic similarity with clopidol, a known bc complex inhibitor containing the 4(1 H)-pyridone scaffold. © 2010 Wiley Periodicals, Inc. Int J Quantum Chem, 2011 [ABSTRACT FROM AUTHOR]

The O–H and S–H homolytic bond dissociation enthalpies of a set of disubstituted phenols and thiophenols (NH2, OH, CH3, Cl, CF3, and NO2) have been computed by a density functional theory procedure with the 6-311++G(d,p) basis set. A very good agreement between our results and available experimental ones is observed. The effect of substituents on structure, charges and BDEs are investigated and their correlation with Hammett parameters is studied. © 2007 Wiley Periodicals, Inc. Int J Quantum Chem, 2008 [ABSTRACT FROM AUTHOR]

Chromosome number, meiotic behavior, and pollen viability were analyzed in 15 species of two genera, Vriesea and Bachman, native to Rio Grande do Sul, Brazil. This study is the first cytogenetic analysis of these taxa. The chromosome numbers are all n = 25, consistent with the proposed base number of x = 25 for Bromeliaceae. All examined taxa displayed regular bivalent pairing and chromosome segregation at meiosis. Observed meiotic abnormalities include univalents in metaphase I; missing or extra chromosomes and precocious division of centromeres in metaphase II; laggards in telophase I and anaphase II/telophase II. The high pollen viability (>88%) reflects a regular meiosis. [ABSTRACT FROM AUTHOR]