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Generalidades. Desde diciembre de 2019 se detectó una nueva infección respiratoria, causada por el virus denominado SARS-CoV-2, decretada posteriormente como pandemia, lo cual ha exigido al personal de salud replantear la forma de prestar sus servicios en salud y garantizar la auto-protección con recursos que han sido insuficientes incluso en los países más desarrollados. Dado que la transmisión del SARS-CoV-2 ocurre a través de aerosoles expulsados de la vía aérea, que pueden ser inhalados o llevados a las mucosas por contacto con las manos contaminadas, se requiere minimizar la posibilidad de contagio para los equipos de atención en salud. Objetivos. Brindar herramientas a los cirujanos que les permitan elegir la técnica con menor probabilidad de exposición a aerosoles. Describir el paso a paso de la técnica quirúrgica de la traqueostomía percutánea, enfatizando en el control sobre la generación de aerosoles en pasos críticos. Aspectos técnicos. La técnica completamente percutánea con kit de traqueostomía permite un mejor sello entre tejidos y dispositivos. Los escenarios más frecuentes para realizar una traqueostomía son: el paciente intubado con ventilación mecánica y el paciente con falla en la intubación que requiere una intervención de emergencia. Conclusión. El alto contagio del COVID-19 al practicar intervenciones en la vía aérea nos obliga a hacer énfasis en las estrategias que reduzcan la formación de aerosoles y permitan la contención de los mismos durante la realización de traqueostomías.

The nasal epithelium houses a population of solitary chemosensory cells (SCCs). SCCs express bitter taste receptors and taste transduction signaling components and are innervated by peptidergic trigeminal polymodal nociceptive nerve fibers. Thus, nasal SCCs respond to bitter compounds, including bacterial metabolites, and these reactions evoke protective respiratory reflexes and innate immune and inflammatory responses. We tested whether SCCs are implicated in aversive behavior to specific inhaled nebulized irritants using a custom-built dual-chamber forced-choice device. The behavior of mice was recorded and analyzed for the time spent in each chamber. Wild-type (WT) mice exhibited an aversion to 10 mmdenatonium benzoate (Den) or cycloheximide and spent more time in the control (saline) chamber. The SCC-pathway knock-out (KO) mice did not exhibit such an aversion response. The bitter avoidance behavior of WT mice was positively correlated with the concentration increase of Den and the number of exposures. Bitter-ageusic P2X2/3 double KO mice similarly showed an avoidance response to nebulized Den, excluding the taste system’s involvement and pointing to an SCC-mediated major contributor to the aversive response. Interestingly, SCC-pathway KO mice showed an attraction to higher Den concentrations; however, chemical ablation of the olfactory epithelium eliminated this attraction attributed to the smell of Den. These results demonstrate that activation of SCCs leads to a rapid aversive response to certain classes of irritants with olfaction, but not gustation, contributing to the avoidance behavior during subsequent irritant exposures. This SCC-mediated avoidance behavior represents an important defense mechanism against the inhalation of noxious chemicals.

Taste buds comprise four types of taste cells: 3 mature, elongate types: Type I, Type II, Type III; and basally-situated, immature post-mitotic Type IV cells. We employed serial blockface scanning electron microscopy to delineate the characteristics and interrelationships of the taste cells in the circumvallate papillae of adult mice. Type I cells have an indented, elongate nucleus with invaginations, folded plasma membrane, and multiple apical microvilli in the taste pore. Type I microvilli may be either restricted to the bottom of the pore or extend outward reaching midway up into the taste pore. Type II cells (aka receptor cells) are characterized by a large round or oval nucleus, a single apical microvillus extending through the taste pore, and specialized “atypical” mitochondria at functional points of contact with nerve fibers. Type III cells (aka “synaptic cells”) are elongate with an indented nucleus, possess a single, apical microvillus extending through the taste pore and are characterized by a small accumulation of synaptic vesicles at points of contact with nerve fibers. About one-quarter of Type III cells also exhibit an atypical mitochondrion amidst the presynaptic vesicle clusters at the synapse. Type IV cells (non-proliferative “basal cells”) have a nucleus in the lower quarter of the taste bud but have a foot process extending to the basement membrane often contacting nerve processes along the way. Type I cells represent just over 50% of the population, whereas Type II, Type III, and Type IV (basal cells) represent 19%, 15%, and 14% respectively.

Histology, a pillar of anatomical sciences for both health professional and graduate students, requires sufficient time and practice to develop the necessary visual literacy and skills in synthesis to achieve competency. However, histology contact hours in medical and graduate education have reduced significantly in the past decades due to disseminated curricular changes emphasizing integration of basic sciences, clinical content and self-directed learning. In turn, adjunct online resources have been in steady incline and in the past year, in response to COVID-19, quickly became an essential component of anatomical sciences education following campus closures. Self-directed learning is challenging in normal circumstances as success is impacted by the level of student preparedness and engagement, which in turn can be dependent on the quality of the asynchronous learning resources. Although many online histology resources are available, few are comprehensive and provide step-by-step instruction in identification of structures in tissue slides. In this pilot project, the efficacy of using a commercial online histology (COH) course (DaVinci Academy, Cleveland, OH) as a primary preparatory resource in a graduate histology curriculum implementing a flipped-classroom pedagogy was assessed. During fall 2020 (F2020), first-year graduate students enrolled in a hybrid histology course were required to review learning objectives, read textbook sections, and complete the COH lessons, consisting of complete lectures, lab videos, and quizzes as a set of pre-work to prepare for on-campus and virtual classes. The synchronous class sessions had minimal didactic lectures, but instead had a series of small group active learning tasks. In a COMIRB exempt retrospective study (#20-2891), the assessment outcomes of the F2020 cohort (n=26) were compared to a fall 2019 (F2019) cohort of students (n=25) who completed the identical histology curriculum delivered in a flipped-class style by the same instructor, but without the commercial online histology course. All course quiz and exam scores were compared across the F2019 and F2020 cohorts using a Kruskal Wallis test for non-parametric data. There were no significant differences in assessment outcomes between F2019 and F2020 cohorts (p>0.05). Survey of the F2020 cohort throughout the course revealed consistently high rating of the COH with 80% of students believing the resource improved their ability to read and interpret histology slides. Interestingly, students perceived the lecture and lab videos in the COH delivered by the same in-class instructor to be more valuable than those delivered by a third-party instructor, although the assessment performance was independent of the online instructor (p>0.05). The results suggest that the online histology course can be an effective asynchronous learning resource for a histology course, allowing for more efficient use of synchronous class time to support a higher taxonomy of learning.

The role of biological sex in short-term and long-term outcome after traumatic brain injury (TBI) remains controversial. The observation that exogenous female sex steroids (progesterone and estrogen) reduce brain injury coupled with a small number of clinical studies showing smaller injury in women suggest that sex steroids may play a role in outcome from TBI. We used the controlled cortical impact (CCI) model of TBI in mice to test the hypothesis that after CCI, female mice would demonstrate less injury than male mice, related to the protective role of endogenous steroids. Indeed, adult females exhibit histological protection (3.7 ± 0.5 mm(3)) compared to adult male mice (6.8 ± 0.6 mm(3)), and females that lacked sex steroids (ovex) showed increased injury compared to intact females. Consistent with histology, sensorimotor deficits measured as reduced contralateral limb use were most pronounced in male mice (31.9 ± 6.9% reduced limb use) compared to a 12.7 ± 3.8% reduction in female mice. Ovex mice exhibited behavioral deficits similar to males (31.5 ± 3.9% reduced limb use). Ovex females demonstrated increased microglial activation relative to intact females in both the peri-injury cortex and the reticular thalamic nucleus. Ovex females also demonstrated increased astrogliosis in comparison to both females and males in the peri-injury cortex. These data indicate that female sex steroids reduce brain sensitivity to TBI and that reduced acute neuroinflammation may contribute to the relative protection observed in females.

Mucins are a key component of the airway surface liquid and serve many functions. Given the numerous differences in olfactory versus respiratory nasal epithelia, we hypothesized that mucins would be differentially expressed between these two areas. Secondarily, we evaluated for changes in mucin expression with radiation exposure, given the clinical observations of nasal dryness, altered mucus rheology, and smell loss in radiated patients. Immunofluorescence staining was performed in a mouse model to determine the expression of mucins 1, 2, 5AC and 5B in nasal respiratory and olfactory epithelia of control mice and one week after exposure to 8 gy of radiation. Mucins 1, 5AC and 5B exhibited differential expression between olfactory and respiratory epithelium while mucin 2 showed no difference. Within the olfactory epithelium, mucin 1 was located in a lattice-like pattern around gaps corresponding to dendritic knobs of olfactory sensory neurons, whereas in respiratory epithelium it was only intermittently expressed. Mucin 5AC was expressed by subepithelial glands in both epithelial types but to a higher degree in the olfactory epithelium. Mucin 5B was expressed by submucosal glands in the olfactory epithelium but by surface epithelial cells in respiratory epithelium. At one-week after exposure to single-dose 8 gy of radiation, no qualitative effects were seen on mucin expression. Our findings demonstrate that murine olfactory and respiratory epithelia express mucins differently, and characteristic patterns of mucins 1, 5AC, and 5B can be used to define the underlying epithelium. Radiation (8 gy) does not appear to affect mucin expression at one week.Author RolesChristopher Kennel conceived, organized and executed the study, performed the analysis, and contributed to the manuscript.Elizabeth Gould conceived and executed the study, and contributed to the manuscript.Diego Restrepo conceived and executed the study, supervised the experiments, reviewed the analysis, and contributed to the manuscript.Ernesto Salcedo performed experiments and reviewed the manuscript.Thad Vickery performed experiments and reviewed the manuscript.Eric Larson performed experiments and reviewed the manuscript.Vijay Ramakrishnan conceived and executed the study, reviewed the analysis, and contributed to the manuscript.All authors discussed the results and implications and contributed to the final manuscript.

Background: In patients hospitalized with 1) newly diagnosed heart failure (HF) or 2) acute myocardial infarction (AMI), assessment of left ventricular systolic function is a high-value test supported by guidelines. We examined the degree to which patient-, payer-, and hospital-level characteristics impact use of testing. Methods: We analyzed data from the Colorado All-Payer Claims Database, a repository of billing claims from all insurers who provide care in the state. We identified all patients with an index hospitalization for HF and AMI from 2010 to 2014. We excluded patients with a prior diagnosis of HF, and hospitals with fewer than 40 HF or AMI hospitalizations. We determined whether patients had a systolic function assessment performed within 60 days of hospitalization. We calculated adjusted rates of testing at the hospital level, and assessed for correlation of rates between HF and AMI patients. We used multilevel logistic regression to assess patient- and payer- characteristics associated with testing, and used median odds ratios to determine the residual variation in testing attributable to hospitals. Results: We identified 9,516 patients with HF and 10,315 patients with AMI (mean age 73 years, 48% women) among 36 hospitals. Overall, 74% of HF patients and 73% of AMI patients received testing. Testing rates among hospitals ranged from 56% to 82% for HF and from 42% to 83% for AMI (Figure). Correlation of testing rates for AMI and HF patients among hospitals was moderate (Spearman r=0.58; p Conclusions: Despite adjustment for patient- and payer-level characteristics, there is 1) significant residual variation in use of high-value cardiac testing and 2) correlation in testing rates for AMI and HF patients among hospitals. These results suggest that hospital-level characteristics and care processes may have a strong influence on use of high-value testing.

Neural crest cells (NCCs) are essential embryonic progenitor cells that are unique to vertebrates and form a remarkably complex and coordinated system of highly motile cells. Migration of NCCs occurs along specific pathways within the embryo in response to both environmental cues and cell–cell interactions within the neural crest population. Here, we demonstrate a novel role for the putative Sonic hedgehog (Shh) receptor and cell adhesion regulator, cdon, in zebrafish neural crest migration. cdon is expressed in developing premigratory NCCs but is downregulated once the cells become migratory. Knockdown of cdon results in aberrant migration of trunk NCCs: crestin positive cells can emigrate out of the neural tube but stall shortly after the initiation of migration. Live cell imaging analysis demonstrates reduced directedness of migration, increased velocity and mispositioned cell protrusions. In addition, transplantation analysis suggests that cdon is required cell-autonomously for directed NCC migration in the trunk. Interestingly, N-cadherin is mislocalized following cdon knockdown suggesting that the role of cdon in NCCs is to regulate N-cadherin localization. Our results reveal a novel role for cdon in zebrafish neural crest migration, and suggest a mechanism by which Cdon is required to localize N-cadherin to the cell membrane in migratory NCCs for directed migration.

Introducción. La independencia judicial constituye una garantía del debido proceso y uno de los presupuestos esenciales para el mejor funcionamiento del poder judicial. Metodología. El estudio de una garantía que impide la injerencia de los otros poderes en la resolución de los asuntos sometidos al conocimiento de jueces y tribunales, es abordado, a través del estudio de los principales Instrumentos jurídicos internacionales, las Constituciones y leyes nacionales y también del análisis de casos resueltos por la jurisprudencia nacional y la Corte Interamericana de Derechos Humanos. Resultados y conclusiones. Asuntos como la forma de elección de los jueces y magistrados, la duración del mandato, las evaluaciones de su desempeño y las injerencias externas en su actuación, son abordados desde diferentes enfoques doctrinales y también desde Derecho comparado, con el objetivo de medir el grado de confianza del pueblo en su sistema judicial, como parte fundamental de la democracia.

The integrity of taste buds is intimately dependent on an intact gustatory innervation, yet the molecular nature of this dependency is unknown. Here, we show that differentiation of new taste bud cells, but not progenitor proliferation, is interrupted in mice treated with a hedgehog (Hh) pathway inhibitor (HPI), and that gustatory nerves are a source of sonic hedgehog (Shh) for taste bud renewal. Additionally, epithelial taste precursor cells express Shh transiently, and provide a local supply of Hh ligand that supports taste cell renewal. Taste buds are minimally affected when Shh is lost from either tissue source. However, when both the epithelial and neural supply of Shh are removed, taste buds largely disappear. We conclude Shh supplied by taste nerves and local taste epithelium act in concert to support continued taste bud differentiation. However, although neurally derived Shh is in part responsible for the dependence of taste cell renewal on gustatory innervation, neurotrophic support of taste buds likely involves a complex set of factors.

Taste buds are assemblies of elongated epithelial cells, which are innervated by gustatory nerves that transmit taste information to the brain stem. Taste cells are continuously renewed throughout life via proliferation of epithelial progenitors, but the molecular regulation of this process remains unknown. During embryogenesis, sonic hedgehog (SHH) negatively regulates taste bud patterning, such that inhibition of SHH causes the formation of more and larger taste bud primordia, including in regions of the tongue normally devoid of taste buds. Here, using a Cre-lox system to drive constitutive expression of SHH, we identify the effects of SHH on the lingual epithelium of adult mice. We show that misexpression of SHH transforms lingual epithelial cell fate, such that daughter cells of lingual epithelial progenitors form cell type-replete, onion-shaped taste buds, rather than non-taste, pseudostratified epithelium. These SHH-induced ectopic taste buds are found in regions of the adult tongue previously thought incapable of generating taste organs. The ectopic buds are composed of all taste cell types, including support cells and detectors of sweet, bitter, umami, salt and sour, and recapitulate the molecular differentiation process of endogenous taste buds. In contrast to the well-established nerve dependence of endogenous taste buds, however, ectopic taste buds form independently of both gustatory and somatosensory innervation. As innervation is required for SHH expression by endogenous taste buds, our data suggest that SHH can replace the need for innervation to drive the entire program of taste bud differentiation.

Olfactory sensory neurons that express transient receptor potential channel M5 (TrpM5) or neurotrophin-3 (NT-3) project to defined clusters of glomeruli situated ventrally in the main olfactory bulb. Using genetically labeled mice, we investigated whether expression of NT-3-driven βgal and TrpM5-driven GFP marked overlapping sets of glomeruli and whether expression of these markers was coordinated. Our results indicate that these markers largely characterize independent sets of olfactory sensory neuron axons and glomeruli. Further, in glomeruli in which both TrpM5-GFP and NT-3-βgal labeled axons occur, they are expressed independently. The nature of staining for these two markers also differs within glomeruli. Within each labeled TrpM5-positive glomerulus, the level of TrpM5-GFP expression was similar throughout the glomerular neuropil. In contrast, NT-3-driven βgal expression levels are heterogeneous even within heavily labeled glomeruli. In addition, a population of very small TrpM5-GFP positive glomeruli is apparent while no similar populations of NT-3-βgal glomeruli are evident. Taken together, these data suggest that TrpM5 and NT-3 characterize two largely independent receptor populations both conveying odorant information to the ventral olfactory bulb.

Familial dysautonomia (FD) is an autosomal recessive congenital neuropathy that is caused by a mutation in the gene for inhibitor of kappa B kinase complex-associated protein (IKBKAP). Although FD patients suffer from multiple neuropathies, a major debilitation that affects their quality of life is progressive blindness. To determine the requirement forIkbkapin the developing and adult retina, we generatedIkbkapconditional knockout (CKO) mice using aTUBA1apromoter-Cre (Tα1-Cre). In the retina,Tα1-Creexpression is detected predominantly in retinal ganglion cells (RGCs). At 6 months, significant loss of RGCs had occurred in the CKO retinas, with the greatest loss in the temporal retina, which is the same spatial phenotype observed in FD, Leber hereditary optic neuropathy, and dominant optic atrophy. Interestingly, the melanopsin-positive RGCs were resistant to degeneration. By 9 months, signs of photoreceptor degeneration were observed, which later progressed to panretinal degeneration, including RGC and photoreceptor loss, optic nerve thinning, Müller glial activation, and disruption of layers. Taking these results together, we conclude that althoughIkbkapis not required for normal development of RGCs, its loss causes a slow, progressive RGC degeneration most severely in the temporal retina, which is later followed by indirect photoreceptor loss and complete retinal disorganization. This mouse model of FD is not only useful for identifying the mechanisms mediating retinal degeneration, but also provides a model system in which to attempt to test therapeutics that may mitigate the loss of vision in FD patients.

We performed stimulated emission depletion (STED) imaging of isolated olfactory sensory neurons (OSNs) using a custom-built microscope. The STED microscope uses a single pulsed laser to excite two separate fluorophores, Atto 590 and Atto 647N. A gated timing circuit combined with temporal interleaving of the different color excitation/STED laser pulses filters the two channel detection and greatly minimizes crosstalk. We quantified the instrument resolution to be ∼81 and ∼44 nm, for the Atto 590 and Atto 647N channels. The spatial separation between the two channels was measured to be under 10 nm, well below the resolution limit. The custom-STED microscope is incorporated onto a commercial research microscope allowing brightfield, differential interference contrast, and epifluorescence imaging on the same field of view. We performed immunolabeling of OSNs in mice to image localization of ciliary membrane proteins involved in olfactory transduction. We imaged Ca2+-permeable cyclic nucleotide gated (CNG) channel (Atto 594) and adenylyl cyclase type III (ACIII) (Atto 647N) in distinct cilia. STED imaging resolved well-separated subdiffraction limited clusters for each protein. We quantified the size of each cluster to have a mean value of 88±48 nm and 124±43 nm, for CNG and ACIII, respectively. STED imaging showed separated clusters that were not resolvable in confocal images.

Background: Rhodopsin absorption is regulated by interactions between the retinal chromophore and amino acids within the opsin apoprotein. Results: Site-directed mutagenesis of conserved residues has only modest effects on Drosophila Rhodopsin 1 absorption. Conclusion: The counterion may reside at another site within the protein or other mechanisms may compensate. Significance: Determining the molecular basis for rhodopsin spectral tuning is essential for understanding rhodopsin function and evolution., The molecular mechanisms that regulate invertebrate visual pigment absorption are poorly understood. Studies of amphioxus Go-opsin have demonstrated that Glu-181 functions as the counterion in this pigment. This finding has led to the proposal that Glu-181 may function as the counterion in other invertebrate visual pigments as well. Here we describe a series of mutagenesis experiments to test this hypothesis and to also test whether other conserved acidic amino acids in Drosophila Rhodopsin 1 (Rh1) may serve as the counterion of this visual pigment. Of the 5 Glu and Asp residues replaced by Gln or Asn in our experiments, none of the mutant pigments shift the absorption of Rh1 by more than 6 nm. In combination with prior studies, these results suggest that the counterion in Drosophila Rh1 may not be located at Glu-181 as in amphioxus, or at Glu-113 as in bovine rhodopsin. Conversely, the extremely low steady state levels of the E194Q mutant pigment (bovine opsin site Glu-181), and the rhabdomere degeneration observed in flies expressing this mutant demonstrate that a negatively charged residueat this position is essential for normal rhodopsin function in vivo. This work also raises the possibility that another residue or physiologic anion may compensate for the missing counterion in the E194Q mutant.

This study was designed to identify the incidence of late complete heart block (CHB) first identified at least 48 hours post alcohol septal ablation (ASA).Septal reduction with ASA is a therapeutic option for patients with symptomatic hypertrophic obstructive cardiomyopathy (HCM). CHB, resulting from the septal infarct, is a known complication with a reported incidence of 9-22%. The incidence of CHB more than 48 hours post-procedure is unknown.Consecutive patients who underwent ASA were analyzed and clinical characteristics associated with late CHB were assessed. Late CHB was defined as first identification of CHB more than 48 hours after ASA.From 2002-2013, 145 subjects underwent 168 ASA procedures and were followed for a mean of 3.2 +/- 2.3 years. The incidence of late CHB was 8.9% (15/168 ASA procedures). Heart block occurred from 48 hours to 3-years post-procedure. In a multivariable model, patients with any CHB were more likely to have had multiple ASA procedures (OR 4.14; 95% CI: 1.24, 13.9; P 0.05) and high resting and provoked left ventricular outflow tract (LVOT) gradient assessed by catheterization (OR per 10 mmHg gradient 1.14; 95% CI: 1.0, 1.20; P 0.05). After multivariable adjustment, only a high provokable LVOT gradient remained an independent predictor of late CHB (OR per 10 mmHg gradient 1.14 [95% CI 1.02-1.29]).Late CHB is a common complication of ASA for treatment of symptomatic HCM. Post-discharge electrocardiographic surveillance for atrioventricular conduction disease should be considered after ASA, especially for those with a high provokable LVOT gradient.

Color discrimination requires the input of different photoreceptor cells that are sensitive to different wavelengths of light. TheDrosophilavisual system contains multiple classes of photoreceptor cells that differ in anatomical location, synaptic connections, and spectral sensitivity. The Rh5 and Rh6 opsins are expressed in nonoverlapping sets of R8 cells and are the onlyDrosophilavisual pigments that remain uncharacterized. In this study, we ectopically expressed Rh5 and Rh6 in the major class of photoreceptor cells (R1–R6) and show them to be biologically active in their new environment. The expression of either Rh5 or Rh6 in “blind”ninaE17mutant flies, which lack the gene encoding the visual pigment of the R1–R6 cells, fully rescues the light response. Electrophysiological analysis showed that the maximal spectral sensitivity of the R1–R6 cells is shifted to 437 or 508 nm when Rh5 or Rh6, respectively, is expressed in these cells. These spectral sensitivities are in excellent agreement with intracellular recordings of the R8p and R8y cells measured inCalliphoraandMusca. Spectrophotometric analyses of Rh5 and Rh6in vivoby microspectrophotometry, and of detergent-extracted pigmentsin vitro, showed that Rh5 is reversibly photoconverted to a stable metarhodopsin (λmax= 494 nm), whereas Rh6 appears to be photoconverted to a metarhodopsin (λmax= 468 nm) that is less thermally stable. Phylogenetically, Rh5 belongs to a group of short-wavelength-absorbing invertebrate visual pigments, whereas Rh6 is related to a group of long-wavelength-absorbing pigments and is the first member of this class to be functionally characterized.

The honeybee (Apis mellifera) visual system contains three classes of retinal photoreceptor cells that are maximally sensitive to light at 440 nm (blue), 350 nm (ultraviolet), and 540 nm (green). We performed a PCR-based screen to identify the genes encoding theApisblue- and ultraviolet (UV)-sensitive opsins. We obtained cDNAs that encode proteins having a high degree of sequence and structural similarity to other invertebrate and vertebrate visual pigments. TheApisblue opsin cDNA encodes a protein of 377 amino acids that is most closely related to other invertebrate visual pigments that are thought to be blue-sensitive. The UV opsin cDNA encodes a protein of 371 amino acids that is most closely related to the UV-sensitiveDrosophilaRh3 and Rh4 opsins. To test whether these novelApisopsin genes encode functional visual pigments and to determine their spectral properties, we expressed them in the R1–6 photoreceptor cells of blindninaEmutantDrosophila, which lack the major opsin of the fly compound eye. We found that the expression of either theApisblue- or UV-sensitive opsin in transgenic flies rescued the visual defect ofninaEmutants, indicating that both genes encode functional visual pigments. Spectral sensitivity measurements of these flies demonstrated that the blue and UV visual pigments are maximally sensitive to light at 439 and 353 nm, respectively. These maxima are in excellent agreement with those determined previously by single-cell recordings fromApisphotoreceptor cells and provide definitive evidence that the genes described here encode visual pigments having blue and UV sensitivity.

Although the olfactory system is not generally associated with seizures, sharp application of odor eliciting activity in a large number of olfactory sensory neurons (OSNs) has been shown to elicit seizures. This is most likely due to increased ictal activity in the anterior piriform cortex— an area of the olfactory system that has limited GABAergic interneuron inhibition of pyramidal output cell activity. Such hyperexcitability in a well-characterized and highly accessible system makes olfaction a potentially powerful model system to examine epileptogenesis.

Major histocompatibility class I (MHCI) molecules are well known for their immunological role in mediating tissue graft rejection. Recently, these molecules were discovered to be expressed in distinct neuronal subclasses, dispelling the long-held tenet that the uninjured brain is immune-privileged. Here, we show that MHCI molecules are expressed in the main olfactory bulb (MOB) of adult animals. Furthermore, we find that mice with diminished levels of MHCI expression have enlarged MOBs containing an increased number of small, morphologically abnormal and ectopically located P2 glomeruli. These findings suggest that MHCI molecules may play an important role in the proper formation of glomeruli in the bulb.

We present a rare and unique case of calcific constrictive pericarditis with a calcified pericardial mass invading the right ventricular myocardium. Perioperative two-dimensional and three-dimensional transesophageal echocardiography revealed the extent and structure of the pericardial mass and led to the repair of the right ventricular free wall as a surgical intervention.

This case report describes a rare complication that occurred during the performance of a MitraClip procedure. Following deployment of the clip, the portion of the device that attaches the clip to the clip delivery system (CDS), referred to as the radiopaque tip, embolized to the left atrium during removal of the CDS through the guide catheter. The percutaneous strategy that was used to successfully retrieve the radiopaque tip is described and discussed.

Se presentan los resutados obtenidos al procesar 1588 sueros humanos, enviados para el diagnostico de Histoplasmosis. en un periodo de 3 anos, utilizandose la tecnica de contrainmunoelectroforesis, por ser mas sensible y mas rapida que la de Inmunodifusion. La asociacion de las bandas de precipitacion H y M se encontro en alto porcentaje en los sueros de personas que no presentaban sintomas clinicos, corroborando que la enfermedad activa puede evolucionar asintomaticamente. El mayor porcentaje de la sola presencia de la banda de precipitacion M en el suero de pacientes con sintomas de la enfermedad activa, nos demuestra que la banda H puede estar ausente en estos casos. La mayor cantidad de sueros positivos en el sexo masculino es posible que este determinada por la actividad laboral y no por los factores relacionados con el sexo. Los casos positivos en sueros procedentes de hospitales pediatricos, nos alerta de que en los ninos tambien puede encontrarse la enfermedad.

Se estudiaron clinica-epidemiologicamente 54 casos confirmados de Microsporum canis en el Laboratorio de Micologia del Hospital ''Antonio Luaces Iraola" de la provincia Ciego de Avila Cuba. en el periodo de 1984 a 1987. La tasa global fue de 16.1 por 100.000 habitantes y los anos de mayor incidencia fueron 1984 y 1985. Predominaron los casos aislados sobre los casos en brotes epidemicos. Fue mas frecuente el diagnostico en ninos que en adultos y los de mayor incidencia en los grupos de edades de 2 a 4 y 5 a 9 anos. Las localizaciones mas frecuentes fueron el cuero cabelludo. los pies y las manos. Se evaluo al mismo tiempo el contacto con los animales.

Se analizan los estudios micologicas efectuados en pacientes con dermatofilosis entre los anos 1989 a 1991 en la provincia Ciego de Avila, Cuba. Se observo que se incrementaron en los anos analizados el numero de muestras para descartar micosis. El % de positividad global oscilo entre el 10% y el 15%. El mayor porcentaje de aislamientos se obtuvieron de manos y dedos con el 25%, seguido del cuero cabelludo. Trichophyton rubrum fue el dermatofito que se aislo con mas frecuencia, con el 8.3%, seguido del Microsporum canis con el 3,4%.