Variation analysis of genes associated with Usher syndrome type 1 in 136 Chinese deafness families / 中华耳鼻咽喉头颈外科杂志

Objective: To investigate the variation of genes associated with Usher syndrome type 1(USH1)in 136 Chinese deafness families from Henan province. Methods: The data of 136 deafness families tested by next-generation sequencing(NGS) which identified in the center of genetics and prenatal diagnosis of the First Affiliated Hospital of Zhengzhou University from November 2016 to December 2019 were analysized and the variation frequency of six genes related to Usher syndrome type 1(MYO7A, USH1C, CDH23, PCDH15, USH1G, CIB2) were summarized. Results: Five deafness families were detected nine pathogenic or likely pathogenic variations in two genes, accounting for 3.7% of all families. Among them, four families were caused by MYO7A variations and one family was caused by CDH23 variation. Meanwhile, seven variations of two genes were reported for the first time. They were c.313delG, c.5257dupA, c.5435A>T, c.5636G>C, c.5722T>G of MYO7A, and c.155_166del, c.4802delA of CDH23. The patients' vision of family 2 and family 3 had no obvious abnormality at present, but according to genetic diagnosis and walking dealy, they were considered to be USH1. Conclusions: MYO7A is the most common caustive gene associated with USH1 in Henan deafness patients, the application of next-generation sequencing technology can make USH1 patients diagnosed earlier before the visual symptoms appear.

Myosin 1H and the soft tissue profile of african american females with mandibular prognathism

Introduction: The aim of this study was to explore the influence of Myosin 1H on the soft tissue profile of African American females. Methods: Fourteen African American females from the University of Pittsburgh School of Dental Medicine Dental Registry and DNA Repository with the ancestral genotype GG, marker rs10850110, locus 12q24.11 were analyzed. For this investigation, measurements were taken of the eleven items that comprise the Holdaway soft tissue analysis. Profile differences between ethnicity and corresponding normative values were explored by independent-sample t tests for all facial profile measurements. Student's t test for independent means was used to determine differences with accepted norms. Significance was set a p<0.05. Results: There were significant differences between four of the eleven Holdaway values and the reported values for African Americans. The mean convexity value of the African American female group was 1.0 mm less the normative value of 5.7 mm (p>0.000). In contrast, the H angle of the African American females was larger than the normative value. Conclusions: Our study confirms previous research that Myosin 1H contributes to mandibular prognathism. It agrees with the idea that Myosin 1H is less influential in the maxillary soft tissue complex. Understanding the genetic influence of soft tissue growth would allow improved therapies and prevention approaches.

Introduçâo: O objetivo desse estudo foi determinar a influência da miosina 1H nos tecidos moles de mulheres americanas negras. Métodos: Foram estudadas quatorze mulheres americanas negras participantes do projeto Dental Registry and DNA Repository da Faculdade de Odontologia da Universidade de Pittsburgh com o genótipo comum GG do marcador rs10850110, localizado no lócus 12q24.11. Medidas de onze parâmetros que compõem a análise de tecidos moles de Holdaway foram utilizadas. Diferenças entre etnicidade e medidas normais correspondentes, foram exploradas através do teste t de Student de amostras independentes para todas as medidas faciais. O teste t de Student para médias independentes foi usado para determinar diferenças em comparação à medidas normais. A significância foi estabelecida em p<0,05. Resultados: Houve uma diferença estatisticamente significante entre quatro das onze medidas de Holdaway. A convexidade média da mulher americana negra foi de 1,0 mm a menos que o valor normal de 5.7 mm (p>0.000). Em contraste, o ângulo H das mulheres americanas negras foi maior que o valor normal. Conclusões: O nosso estudo confirma resultados anteriores que a miosina 1H contribui para o prognatismo mandibular. Nossos resultados concordam com a ideia de que a miosina 1H tem menor influência nos tecidos moles da maxila. Entender a influência genética no crescimento dos tecidos moles irá possivelmente permitir melhorar as abordagens de tratamento e prevenção atuais.

Analysis of MYO7A gene mutation in a family with non-syndromic autosomal recessive deafness / 中华医学遗传学杂志

OBJECTIVE@#To explore the genetic basis for a family with non-syndromic autosomal recessive deafness.@*METHODS@#The proband and her parents were subjected to physical and audiological examinations. With genomic DNA extracted from peripheral blood samples, next-generation sequencing was carried out using a panel for deafness genes. Suspected mutation was validated by Sanger sequencing and qPCR analysis of her parents.@*RESULTS@#The proband presented bilateral severe sensorineural hearing loss at three days after birth. Her auditory threshold was 110-120 dBnHL but with absence of vestibular and retinal symptoms. Her brother also had deafness but her parents were normal. No abnormality was found upon physical examination of her family members, while audiological examination showed no middle ear or retrocochlear diseases. Next-generation sequencing identified compound heterozygous mutations of the MYO7A gene, including a previously known c.462C>A (p. Cys154Ter) and a novel EX43_46 Del, which were respectively derived from her mother and father.@*CONCLUSION@#The compound heterozygous mutations of the MYO7A gene probably underlie the disease in this family. Our findings has enriched the mutation spectrum for non-syndromic autosomal recessive deafness 2.

Endobronchial Smooth Muscle Tumors: A Series of Five Cases Highlighting Pitfalls in Diagnosis

BACKGROUND: Primary endobronchial smooth muscle tumors (SMTs), which are extremely rare, include endobronchial leiomyomas and leiomyosarcomas. Clinically, SMTs present with signs and symptoms of bronchial obstruction, and lack specific radiological findings. Thus, histopathological examination is required for accurate diagnosis as well as for tumor grading. We examined the histomorphological and immunohistochemical features of endobronchial SMTs and highlighted pitfalls in diagnosis, particularly when using small biopsies. METHODS: Cases of primary endobronchial SMTs diagnosed at our Institute over the last 6 years (2012–2017) were retrieved from the departmental archives. Histopathological features and immunohistochemistry performed for establishing the diagnosis were reviewed. RESULTS: Five cases of SMTs occurring in endobronchial locations were identified. These included three cases of leiomyoma, and two cases of leiomyosarcoma. The age distribution of patients ranged from 13 to 65 years. Leiomyomas showed more consistent staining with smooth muscle markers (smooth muscle actin, desmin, and smooth muscle myosin heavy chain), while tumors of higher grade showed variable, focal staining, leading to erroneous diagnosis, especially on small biopsies. CONCLUSIONS: The diagnosis of endobronchial SMTs relies on histopathological examination, for both confirmation of smooth muscle lineage and determination of the malignant potential of the lesion. Appropriate immunohistochemical panels including more than one marker of smooth muscle differentiation are extremely valuable for differential diagnosis from morphological mimics, which is necessary for instituting appropriate management.

α-Isocubebene modulates vascular tone by inhibiting myosin light chain phosphorylation in murine thoracic aorta

α-Iso-cubebene (ICB) is a dibenzocyclooctadiene lignin contained in Schisandra chinensis (SC), a well-known medicinal herb that ameliorates cardiovascular symptoms, but the mechanism responsible for this activity has not been determined. To determine the role played by ICB on the regulation of vascular tone, we investigated the inhibitory effects of ICB on vascular contractile responses by adrenergic α-receptor agonists. In addition, we investigated the role on myosin light chain (MLC) phosphorylation and cytosolic calcium concentration in vascular smooth muscle cells (VSMC). In aortic rings isolated from C57BL/6J mice, ICB significantly attenuated the contraction induced by phenylephrine (PE) and norepinephrine (NE), whereas ICB had no effects on KCl (60 mM)-induced contraction. In vasculatures precontracted with PE, ICB caused marked relaxation of aortic rings with or without endothelium, suggesting a direct effect on VSMC. In cultured rat VSMC, PE or NE increased MLC phosphorylation and increased cytosolic calcium levels. Both of these effects were significantly suppressed by ICB. In conclusion, our results showed that ICB regulated vascular tone by inhibiting MLC phosphorylation and calcium flux into VSMC, and suggest that ICB has anti-hypertensive properties and therapeutic potential for cardiovascular disorders related to vascular hypertension.

Ardipusilloside-I stimulates gastrointestinal motility and phosphorylation of smooth muscle myosin by myosin light chain kinase

Ardipusilloside-I is a natural triterpenoid saponin, which was isolated from Ardisia pusilla A. DC. The aim of the study was to evaluate the stimulation of ardipusilloside-I on gastrointestinal motility in vitro and in vivo. The experiment of smooth muscle contraction directly monitored the contractions of the isolated jejunal segment (IJS) in different contractile states, and the effects of ardipusilloside-I on myosin were measured in the presence of Ca²⁺-calmodulin using the activities of 20 kDa myosin light chain (MLC₂₀) phosphorylation and myosin Mg²⁺-ATPase. The effects of ardipusilloside-I on gastro emptying and intestinal transit in constipation-predominant rats were observed, and the MLCK expression in jejuna of constipated rats was determined by western blot. The results showed that, ardipusilloside-I increased the contractility of IJS in a dose-dependent manner and reversed the low contractile state (LCS) of IJS induced by low Ca²⁺, adrenaline, and atropine respectively. There were synergistic effects on contractivity of IJS between ardipusilloside-I and ACh, high Ca²⁺, and histamine, respectively. Ardipusilloside-I could stimulate the phosphorylation of MLC₂₀ and Mg²⁺-ATPase activities of Ca²⁺- dependent phosphorylated myosin. Ardipusilloside-I also stimulated the gastric emptying and intestinal transit in normal and constipated rats in vivo, respectively, and increased the MLCK expression in the jejuna of constipation-predominant rats. Briefly, the findings demonstrated that ardipusilloside-I could effectively excite gastrointestinal motility in vitro and in vivo.

An optimized micro-assay of myosin II ATPase activity based on the molybdenum blue method and its application in screening natural product inhibitors / 中国天然药物

Myosin II plays multiple roles in physiological and pathological functions through its ATPase activity. The present study was designed to optimize a micro-assay of myosin II ATPase activity based on molybdenum blue method, using a known myosin II ATPase inhibitor, blebbistatin. Several parameters were observed in the enzymatic reaction procedure, including the concentrations of the substrate (ATP) and calcium chloride, pH, and the reaction and incubation times. The proportion of coloration agent was also investigated. The sensitivity of this assay was compared with the malachite green method and bioluminescence method. Additionally, 20 natural compounds were studied for myosin II ATPase inhibitory activity using the optimized method. Our results showed that ATP at the concentration of 5 mmol·L(-1) and ammonium molybdate : stannous chloride at the ratio of 15 : 1 could greatly improve the sensitivity of this method. The IC50 of blebbistatin obtained by this method was consistent with literature. Compound 8 was screened with inhibitory activity on myosin II ATPase. The optimized method showed similar accuracy, lower detecting limit, and wider linear range, which could be a promising approach to screening myosin II ATPase inhibitors in vitro.

Myosin VI contributes to malignant proliferation of human glioma cells

Previously characterized as a backward motor, myosin VI (MYO6), which belongs to myosin family, moves toward the minus end of the actin track, a direction opposite to all other known myosin members. Recent researches have illuminated the role of MYO6 in human cancers, particularly in prostate cancer. However, the role of MYO6 in glioma has not yet been determined. In this study, to explore the role of MYO6 in human glioma, lentivirus-delivered short hairpin RNA (shRNA) targeting MYO6 was designed to stably down-regulate its endogenous expression in glioblastoma cells U251. Knockdown of MYO6 signifi cantly inhibited viability and proliferation of U251 cells in vitro. Moreover, the cell cycle of U251 cells was arrested at G0/G1 phase with the absence of MYO6, which could contribute to the suppression of cell proliferation. In conclusion, we firstly identified the crucial involvement of MYO6 in human glioma. The inhibition of MYO6 by shRNA might be a potential therapeutic method in human glioma.

Myosin heavy chain is stabilized by BCL-2 interacting cell death suppressor (BIS) in skeletal muscle

BCL-2 interacting cell death suppressor (BIS), which is ubiquitously expressed, has important roles in various cellular processes, such as apoptosis, the cellular stress response, migration and invasion and protein quality control. In particular, BIS is highly expressed in skeletal and cardiac muscles, and BIS gene mutations result in human myopathy. In this study, we show that mRNA and protein levels of BIS were markedly increased during skeletal myogenesis in C2C12 cells and mouse satellite cells. BIS knockdown did not prevent the early stage of skeletal myogenesis, but did induce muscle atrophy and a decrease in the diameter of myotubes. BIS knockdown significantly suppressed the expression level of myosin heavy chain (MyHC) without changing the expression levels of myogenic marker proteins, such as Mgn, Cav-3 and MG53. In addition, BIS endogenously interacted with MyHC, and BIS knockdown induced MyHC ubiquitination and degradation. From these data, we conclude that molecular association of MyHC and BIS is necessary for MyHC stabilization in skeletal muscle.

Myosin heavy chain is stabilized by BCL-2 interacting cell death suppressor (BIS) in skeletal muscle

BCL-2 interacting cell death suppressor (BIS), which is ubiquitously expressed, has important roles in various cellular processes, such as apoptosis, the cellular stress response, migration and invasion and protein quality control. In particular, BIS is highly expressed in skeletal and cardiac muscles, and BIS gene mutations result in human myopathy. In this study, we show that mRNA and protein levels of BIS were markedly increased during skeletal myogenesis in C2C12 cells and mouse satellite cells. BIS knockdown did not prevent the early stage of skeletal myogenesis, but did induce muscle atrophy and a decrease in the diameter of myotubes. BIS knockdown significantly suppressed the expression level of myosin heavy chain (MyHC) without changing the expression levels of myogenic marker proteins, such as Mgn, Cav-3 and MG53. In addition, BIS endogenously interacted with MyHC, and BIS knockdown induced MyHC ubiquitination and degradation. From these data, we conclude that molecular association of MyHC and BIS is necessary for MyHC stabilization in skeletal muscle.

Olanzapine May Inhibit Colonic Motility Associated with the 5-HT Receptor and Myosin Light Chain Kinase

OBJECTIVE: To study whether the effects of olanzapine on gastrointestinal motility is related to the serotonin antagonism and myosin light chain kinase. METHODS: Male Sprague-Dawley rats were randomly divided into four groups. Olanzapine gavage was performed for each treatment group during the course of 30 continuous days, while the same volume of saline was given to the rats in the control group. Defecation of the rats was observed on days 7 and 30 after olanzapine gavage. The effects of olanzapine on contraction of colonic smooth muscles were observed in ex vivo experiments. A Western blot was used to evaluate expression levels of the serotonin transporter (SERT) and MLCK in colon segments of the rats. RESULTS: ResultsaaCompared to the control group, 5-160 µM of olanzapine could inhibit dose-dependently the contraction of colonic smooth muscle ex vivo experiments. The maximum smooth muscle contraction effects of 5-HT and acetylcholine significantly decreased after treatment with 40-160 µM of olanzapine. Constipation was found in the olanzapine-treated rats on day 7 and have sustained day 30 after gavage. Expression of MLCK in olanzapine-treated rats was significantly decreased, whereas the expression of SERT significantly increased on the day 7, then significantly decreased on the day 30 after olanzapine gavage. CONCLUSION: SERT and MLCK may involve in the inhibition of colonic contraction induced by olanzapine.

Adequação da assistência pré-natal segundo as características maternas no Brasil / Adequacy of prenatal care according to maternal characteristics in Brazil

OBJETIVO: Verificar o grau de adequação da assistência pré-natal no Brasil e sua associação com características sociodemográficas das mulheres. MÉTODOS: Este estudo nacional de base hospitalar foi realizado com 23 894 mulheres em 2011 e 2012. Os dados foram obtidos a partir de entrevistas com a puérpera e dos cartões de pré-natal. Considerou-se assistência pré-natal adequada aquela iniciada até a 12 semana gestacional, com realização de no mínimo seis consultas (número de consultas corrigido para a idade gestacional no momento do parto), registro no cartão de pré-natal de pelo menos um resultado de cada um dos exames preconizados na rotina de pré-natal e recebimento de orientação para maternidade de referência. Realizou-se regressão logística multivariada para verificar a associação entre características maternas e o grau de adequação da assistência pré-natal. RESULTADOS: Início precoce da atenção pré-natal foi observado em 53,9% das gestantes, número adequado de consultas em 73,2%, registro de pelo menos um exame preconizado em 62,9%, orientação para maternidade de referência em 58,7% e assistência pré-natal global adequada em 21,6%. Menor adequação do pré-natal foi observada em mulheres mais jovens, de pele preta, multíparas, sem companheiro, sem trabalho remunerado, com menos anos de estudo, de classes econômicas mais baixas e residentes nas regiões Norte e Nordeste do país. Após ajuste para características maternas, não foram observadas diferenças entre serviços públicos e privados quanto ao grau de adequação do cuidado pré-natal. CONCLUSÕES: A assistência pré-natal no Brasil alcançou cobertura praticamente universal, mas persistem desigualdades regionais e sociais no acesso a um cuidado adequado. Estratégias para facilitar o ingresso precoce no pré-natal são essenciais.

OBJECTIVE: To verify the degree of adequacy of prenatal care in Brazil and to determine whether it is associated with sociodemographic characteristics of women. METHODS: This nationwide hospital-based study was performed with 23 894 women in 2011 and 2012. Data were obtained from interviews with puerperal women and from the prenatal card recording prenatal care appointments. Adequate prenatal care was defined as that started no later than the 12th gestational week, with performance of at least six consultations (with number of consultations adjusted for gestational age at delivery), record in the prenatal card of at least one result for each of the recommended routine prenatal tests, and guidance regarding the maternity hospital for delivery. Multivariate logistic regression was performed to verify the association between maternal characteristics and the adequacy of prenatal care. RESULTS: Early onset of prenatal care was observed in 53.9% of participants, adequate number of consultations in 73.2%, record of at least one of each recommended test in 62.9%, guidance regarding maternity hospital in 58.7%, and overall adequate prenatal care in 21.6%. Less adequate prenatal care was observed in women who were younger, black, multiparous, who did not have a partner, without paid employment, having fewer years of formal schooling, belonging to lower socioeconomic classes, and living in the North and Northeast of Brazil. After adjustment of maternal characteristics, no differences were observed between public or private health care services regarding adequacy of prenatal care. CONCLUSIONS: Even though the coverage of prenatal care is virtually universal in Brazil, regional and social differences in the access and adequacy of care still persist. The implementation of strategies to facilitate early access to prenatal care is essential.

Isolated Schwannoma of the Olfactory Groove: A Case Report

Introduction Schwannoma of the olfactory groove is an extremely rare tumor that can share a differential diagnosis with meningioma or neuroblastoma. Objectives The authors present a case of giant schwannoma involving the anterior cranial fossa and ethmoid sinuses. Case Report The patient presented with a 30-month history of left nasal obstruction, anosmia, and sporadic ipsilateral bleeding. Computed tomography of the paranasal sinuses revealed expansive lesion on the left nasal cavity extending to nasopharynx up to ethmoid and sphenoid sinuses bilaterally with intraorbital and parasellar extension to the skull base. Magnetic resonance imaging scan confirmed the expansive tumor without dural penetration. Biopsy revealed no evidence of malignancy and probable neural cell. Bifrontal craniotomy was performed combined with lateral rhinotomy (Weber-Ferguson approach), and the lesion was totally removed. The tumor measured 8.0 4.3 3.7 cm and microscopically appeared as a schwannoma composed of interwoven bundles of elongated cells (Antoni A regions)mixed with less cellular regions (Antoni B). Immunohistochemical study stained intensively for vimentin and S-100. Conclusion Schwannomas of the olfactory groove are extremely rare, and the findings of origin of this tumor is still uncertain but recent studies point most probably to the meningeal branches of trigeminal nerve or anterior ethmoidal nerves. .

Proteomic Analysis of the Uterosacral Ligament in Postmenopausal Women with and without Pelvic Organ Prolapse / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Pelvic organ prolapse (POP) is a major health problem in adult women that involves many factors. No proteomic analysis has been conducted exclusively in POP patients. This study aimed to identify the differential expression of proteins that may be involved in POP by proteomic analysis.</p><p><b>METHODS</b>Samples of the uterosacral ligament (USL) were collected from five POP patients and five non-POP patients matched according to age, parity, and menopausal status and analyzed using two-dimensional electrophoresis and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS). Quantitative real-time polymerase chain reaction (qRT-PCR) was used to verify the mRNA expression of proteins that showed differential expression in the proteomic analyses.</p><p><b>RESULTS</b>Proteins differentially expressed between POP and non-POP patients were detected. Eight proteins that were down-regulated in the POP group were identified by MALDI-TOF-MS. These proteins included electron transfer flavoprotein, apolipoprotein A-I, actin, transgelin, cofilin-1, cyclophilin A, myosin, and galectin-1, and their expression was verified by qRT-PCR.</p><p><b>CONCLUSION</b>Using comparative proteomics, we identified eight differentially expressed proteins (including four cytoskeleton proteins and three proteins related to apoptosis) in the USL that may be involved in apoptosis associated with the tissue effects in POP pathophysiology.</p>

Modulatory effects of taurine on jejunal contractility

Taurine (2-aminoethanesulfonic acid) is widely distributed in animal tissues and has diverse pharmacological effects. However, the role of taurine in modulating smooth muscle contractility is still controversial. We propose that taurine (5-80 mM) can exert bidirectional modulation on the contractility of isolated rat jejunal segments. Different low and high contractile states were induced in isolated jejunal segments of rats to observe the effects of taurine and the associated mechanisms. Taurine induced stimulatory effects on the contractility of isolated rat jejunal segments at 3 different low contractile states, and inhibitory effects at 3 different high contractile states. Bidirectional modulation was not observed in the presence of verapamil or tetrodotoxin, suggesting that taurine-induced bidirectional modulation is Ca2+ dependent and requires the presence of the enteric nervous system. The stimulatory effects of taurine on the contractility of isolated jejunal segments was blocked by atropine but not by diphenhydramine or by cimetidine, suggesting that muscarinic-linked activation was involved in the stimulatory effects when isolated jejunal segments were in a low contractile state. The inhibitory effects of taurine on the contractility of isolated jejunal segments were blocked by propranolol and L-NG-nitroarginine but not by phentolamine, suggesting that adrenergic β receptors and a nitric oxide relaxing mechanism were involved when isolated jejunal segments were in high contractile states. No bidirectional effects of taurine on myosin phosphorylation were observed. The contractile states of jejunal segments determine taurine-induced stimulatory or inhibitory effects, which are associated with muscarinic receptors and adrenergic β receptors, and a nitric oxide associated relaxing mechanism.

Standardization of metachromatic staining method of myofibrillar ATPase activity of myosin to skeletal striated muscle of mules and donkeys / Padronização do método de coloração metacromático da atividade da miosina ATPase miofibrilar para músculo estriado esquelético de muares e asininos

This study aims at standardizing the pre-incubation and incubation pH and temperature used in the metachromatic staining method of myofibrillar ATPase activity of myosin (mATPase) used for asses and mules. Twenty four donkeys and 10 mules, seven females and three males, were used in the study. From each animal, fragments from the Gluteus medius muscle were collected and percutaneous muscle biopsy was performed using a 6.0-mm Bergstrõm-type needle. In addition to the metachromatic staining method of mATPase, the technique of nicotinamide adenine dinucleotide tetrazolium reductase (NADH-TR) was also performed to confirm the histochemical data. The histochemical result of mATPase for acidic pre-incubation (pH=4.50) and alkaline incubation (pH=10.50), at a temperature of 37ºC, yielded the best differentiation of fibers stained with toluidine blue. Muscle fibers were identified according to the following colors: type I (oxidative, light blue), type IIA (oxidative-glycolytic, intermediate blue) and type IIX (glycolytic, dark blue). There are no reports in the literature regarding the characterization and distribution of different types of muscle fibers used by donkeys and mules when performing traction work, cargo transportation, endurance sports (horseback riding) and marching competitions. Therefore, this study is the first report on the standardization of the mATPase technique for donkeys and mules...

O presente estudo objetivou padronizar o pH e a temperatura da pré-incubação e incubação do método de coloração metacromática de myofibrillar atividade ATPase da miosina (mATPase) utilizada para asininos e muares. Vinte e quatro jumentos e 10 muares, sete machos e três fêmeas, foram usados no estudo. De cada animal, fragmentos do músculo Gluteus medius foram coletados e biópsia muscular percutânea foi realizada por meio de uma agulha Bergstrõm tipo de 6,0 mm. Em adição ao método de coloração metacromática de mATPase, a técnica de nicotinamida adenina dinucleótido tetrazólio redutase (NADH-TR) foi também realizada para confirmar os dados histoquímicos. O resultado histoquímico da mATPase por pré-incubação ácida (pH=4,50) e incubação alcalina (pH=10,50), a uma temperatura de 37ºC, foi o que proporcionou a melhor diferenciação das fibras coradas com azul de toluidina. As fibras musculares foram identificadas de acordo com as seguintes cores: tipo I (oxidativa, azul claro), tipo IIA (oxidativo-glicolítico, azul intermediário) e tipo IIX (glycolytic, azul escuro). Na literatura, não foram encontradas publicações pertinentes à caracterização e distribuição dos diferentes tipos de fibras musculares utilizadas pelos asininos e muares nos trabalhos de tração, no transporte de cargas, em provas esportivas de resistência (cavalgadas) e concursos de marcha. Dessa forma, essa pesquisa é o primeiro relato sobre padronização da técnica de mATPase para muares e asininos...

Histoquímica enzimática en el diagnósticode miopatías: revisión sistemática / Enzymatic histochemical in the diagnosis of myopathies: a systematic review

Introducción: Las enfermedades del músculo esquelético en las que la lesión supera la capacidad deadaptación conducen a cambios patológicos propios de las miopatías. En Colombia el diagnóstico serealiza mediante tinción con hematoxilina-eosina; sin embargo, la información brindada sobre algunosde los cambios del tejido muscular es limitada, por lo que es necesario realizar algunas técnicas de histoquímicaenzimática según la alteración. Objetivo: Describir los criterios de tinción de diferentes técnicashistoquímicas en el diagnóstico de las miopatías. Materiales y métodos: Se realizó una revisiónsistemática mediante la búsqueda de artículos en inglés y español indexados en las bases de ISI Web ofScience, Ovid Medline, PubMed, ScienceDirect y EBSCO. Los descriptores MeSH utilizados fueron:«histochemistry¼, «skeletal muscle¼, «structural and congenital myopathies¼, «fiber type fast twitch¼,«fiber type slow twitch¼ y «NADH tetrazolium reductase¼. Se asociaron a la búsqueda los términos«clinical application¼ y «diagnosis¼. Se seleccionaron los artículos originales, reportes de casos y revisionespublicadas entre 1982 y 2014 que aplicaran las técnicas de histoquímica en el diagnóstico de unamiopatía o en la investigación biomédica. Resultados: Se seleccionaron 64 publicaciones (incluidosdos libros) que fueron representativos para la redacción de este manuscrito, el cual fue complementadocon imágenes de biopsias musculares procesadas en el Laboratorio de Histología de la Universidad delValle, Colombia...

Introduction: The injuries on skeletal muscle that go beyond their capacity to adaptation result incharacteristic pathological changes of the myopathies. In Colombia for their diagnosis is usually usedthe hematoxylin-eosin stain, however, the information about many changes in muscle tissue is limited.That is why it is necessary to carry out certain enzymatic histochemical staining according to eachmyopathy. Objective: To describe the different criteria to diagnose myopathies by histochemical techniques.Material and methods: A systematic review was conducted which focused on search of all articleswritten in English and Spanish indexed in ISI Web of Science database, Ovid Medline, PubMed,ScienceDirect, and EBSCO. The MeSH descriptors used for the search were «histochemistry¼, «skeletalmuscle¼, «structural and congenital myopathies¼, «fast twitch fiber type¼, «slow twitch fiber type¼,and «NADH tetrazolium reductase¼. The terms «clinical application¼ and «diagnosis¼ were associatedto the search. All original articles, case reports, and reviews published during 1982-2014, which imple-mented histochemical techniques to the diagnosis of myopathy or to biomedical research were included.Results: From systematic search, 64 publications (including two books) were representative for thedrafting of this manuscript. The article was supplemented with images from muscle biopsies processedby the Laboratory of Histology, Universidad del Valle, Colombia...

Characteristics of Diprophylline-Induced Bidirectional Modulation on Rat Jejunal Contractility

In this study, we propose that diprophylline exerts bidirectional modulation (BM) on the isolated rat jejunal segment depending on its contractile state. The results supported the hypothesis. Diprophylline (20 microM) exerted stimulatory effects on the contractility of jejunal segment in six low contractile states while inhibitory effects in six high contractile states, showing the characteristics of BM. Diprophylline-induced stimulatory effect was significantly blocked by atropine, indicating the correlation with cholinergic activation. Diprophylline-induced inhibitory effect was partially blocked by phentolamine, propranolol, and L-N-Nitro-Arginine respectively, indicating their correlation with sympathetic activation and nitric oxide-mediated relaxing mechanisms. Diprophylline-induced BM was abolished by tetrodotoxin or in a Ca2+ free condition or pretreated with tyrosine kinase inhibitor imatinib, suggesting that diprophylline-induced BM is Ca2+ dependent, and that it requires the presence of enteric nervous system as well as pacemaker activity of interstitial cells of Cajal. Diprophylline significantly increased the reduced MLCK expression and myosin extent in constipation-prominent rats and significantly decreased the increased MLCK expression and myosin extent in diarrhea-prominent rats, suggesting that the change of MLCK expression may also be involved in diprophylline-induced BM on rat jejunal contractility. In summary, diprophylline-exerted BM depends on the contractile states of the jejunal segments, requires the presence of Ca2+, enteric nervous system, pacemaker activity of interstitial cells of Cajal, and MLCK-correlated myosin phosphorylation. The results suggest the potential implication of diprophylline in relieving alternative hypo/hyper intestinal motility.

Linkage study of DFNB3 responsible for hearing loss in human.

BACKGROUND: Hearing disorders represent a significant health problem worldwide. Recessive inherited cases of the deafness are more prevalent in Pakistan due to consanguineous marriages. Deafness caused by DFNB3 is due to mutation in the gene MYO XVA and its prevalence among Pakistani population is about 5%. MATERIALS AND METHODS: Families with at least two or more individual affected with deafness were selected from different areas of District Okara of Pakistan. Six consanguineous families of different ethnic groups having deaf individuals were studied. All these families had three or more deaf individuals in either two or more sib ships. Family history was taken to minimize the chances of other abnormalities. Pedigrees drawn by using Cyrillic software (version 2.1) showed that all the marriages were consanguineous and the families have recessive mode of inheritance. Three STR markers were selected and amplified on all the samples of six families through PCR. The PCR products were then genotyped on non denaturing polyacrylamide gel electrophoresis (PAGE). Haplotypes were constructed to determine the pattern of inheritance and also to determine whether a family was linked or unlinked with known DFNB3 locus. RESULTS: One out of six families showed linkage to the DFNB3 while rest of the families remained unlinked. Carriers of deafness genes were identified and information was provided to the families on request. CONCLUSION: Knowledge about the genetic causes of deafness provide insight into the variable expression of genes involved in this hereditary problem and may allow the prediction and prevention of associated health problems.

Acute exposure to lead increases myocardial contractility independent of hypertension development

We studied the effects of the acute administration of small doses of lead over time on hemodynamic parameters in anesthetized rats to determine if myocardial contractility changes are dependent or not on the development of hypertension. Male Wistar rats received 320 µg/kg lead acetate iv once, and their hemodynamic parameters were measured for 2 h. Cardiac contractility was evaluated in vitro using left ventricular papillary muscles as were Na+,K+-ATPase and myosin Ca2+-ATPase activities. Lead increased left- (control: 112 ± 3.7 vs lead: 129 ± 3.2 mmHg) and right-ventricular systolic pressures (control: 28 ± 1.2 vs lead: 34 ± 1.2 mmHg) significantly without modifying heart rate. Papillary muscles were exposed to 8 µM lead acetate and evaluated 60 min later. Isometric contractions increased (control: 0.546 ± 0.07 vs lead: 0.608 ± 0.06 g/mg) and time to peak tension decreased (control: 268 ± 13 vs lead: 227 ± 5.58 ms), but relaxation time was unchanged. Post-pause potentiation was similar between groups (n = 6 per group), suggesting no change in sarcoplasmic reticulum activity, evaluated indirectly by this protocol. After 1-h exposure to lead acetate, the papillary muscles became hyperactive in response to a β-adrenergic agonist (10 µM isoproterenol). In addition, post-rest contractions decreased, suggesting a reduction in sarcolemmal calcium influx. The heart samples treated with 8 µM lead acetate presented increased Na+,K+-ATPase (approximately 140%, P < 0.05 for control vs lead) and myosin ATPase (approximately 30%, P < 0.05 for control vs lead) activity. Our results indicated that acute exposure to low lead concentrations produces direct positive inotropic and lusitropic effects on myocardial contractility and increases the right and left ventricular systolic pressure, thus potentially contributing to the early development of hypertension.