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1.
Oman Med J ; 39(1): e590, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-39006310

RESUMO

Objectives: To evaluate the hypothesis that human leukocyte antigens (HLAs) confer susceptibility to schizophrenic disorders, by assessing their contribution to the risk of schizophrenia in a Yemeni population. Methods: The researchers approached patients who had been diagnosed with schizophrenia at Al-Amal Hospital for Psychiatric Diseases, Sana'a. Controls were drawn randomly from the general population. The HLA class II alleles of the participants were examined. The genotypes of the HLA-DQB1 and HLA-DRB1 alleles were determined by polymerase chain reaction using sequence-specific primers. Results: The subjects comprised 110 patients with schizophrenia, matched by an equal number of controls. The prevalence of HLA-DRB1*04 was significantly higher among patients than among controls (7.3% vs. 0.0%; p =0.003), as was HLA-DRB1*07 (62.7% vs. 17.3%, odds ratio (OR) = 8.1, 95% CI: 4.3-15.1; p < 0.001). HLA-DRBI*14 was significantly less prevalent among patients (0.9% vs. 11.8%, OR = 0.06, 95% CI: 0.01-0.50, χ2 = 10.9; p < 0.001). HLA-DQB1*07 was the most common allele discovered in schizophrenia patients and was found to have a much higher incidence in patients than the control group (22.7% vs. 4.5%, OR = 6.2, 95%CI: 2.3-16.8, χ2 = 15.4; p < 0.001). Conclusions: The HLA-DQB1 and HLA-DRB1 gene loci are linked to schizophrenia in the Yemeni population, according to the current study's evidence.

2.
Saudi Dent J ; 36(4): 539-545, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38690386

RESUMO

Introduction: Endodontic treatment failures often stem from the presence of microbial pathogens, particularly Enterococcus faecalis and Candida albicans. This study systematically assesses the prevalence of E. faecalis and C. albicans in endodontic retreatment cases, aiming to explore their impact on treatment outcomes. Methods: Employing a systematic sampling approach, 30 patients with a history of previous endodontic treatment were selected. Rigorous clinical and radiographic assessments were conducted, following standardized protocols for root canal sample collection. Microbiological analysis, utilizing selective culture media, was employed to identify and quantify E. faecalis and C. albicans. Statistical analyses, including chi-square and logistic regression tests, were performed. Results: The study involved 30 patients undergoing endodontic retreatment, with comprehensive clinical and radiographic evaluations for cases with and without periradicular lesions. Microbiological analysis unveiled a significant prevalence of E. faecalis and C. albicans, establishing a robust association between these pathogens and retreatment failure. These findings underscore the critical need for targeted antimicrobial interventions to enhance the overall success rates of endodontic retreatment procedures. Conclusion: This study highlights the substantial prevalence of E. faecalis and C. albicans in endodontic retreatment cases, emphasizing the importance of identifying and effectively managing these pathogens for successful treatment outcomes. The notable association between these microbial agents and retreatment failure underscores the imperative for tailored antimicrobial strategies to enhance the efficacy of endodontic retreatment procedures.

3.
Neuron ; 111(14): 2232-2246.e5, 2023 07 19.
Artigo em Inglês | MEDLINE | ID: mdl-37192623

RESUMO

Although the hippocampus is crucial for social memory, how social sensory information is combined with contextual information to form episodic social memories remains unknown. Here, we investigated the mechanisms for social sensory information processing using two-photon calcium imaging from hippocampal CA2 pyramidal neurons (PNs)-which are crucial for social memory-in awake head-fixed mice exposed to social and non-social odors. We found that CA2 PNs represent social odors of individual conspecifics and that these representations are refined during associative social odor-reward learning to enhance the discrimination of rewarded compared with unrewarded odors. Moreover, the structure of the CA2 PN population activity enables CA2 to generalize along categories of rewarded versus unrewarded and social versus non-social odor stimuli. Finally, we found that CA2 is important for learning social but not non-social odor-reward associations. These properties of CA2 odor representations provide a likely substrate for the encoding of episodic social memory.


Assuntos
Região CA2 Hipocampal , Odorantes , Camundongos , Animais , Olfato/fisiologia , Hipocampo/fisiologia , Aprendizagem , Aprendizagem por Discriminação/fisiologia
4.
J Infect Public Health ; 16(6): 917-921, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37084617

RESUMO

BACKGROUND: Device-associated infections (DAIs) are important components of healthcare associated infection and are associated with increased morbidity and mortality. This study describes DAIs across different intensive care units (ICUs) in a hospital in Saudi Arabia. METHODS: The study was conducted between 2017 and 2020 and followed the definitions of National Healthcare Safety Network (NHSN) for DAIs. The calculated the rates of ventilator-associated events (VAE), catheter-associated urinary tract infections (CAUTI) and central line-associated blood stream infections (CLABSI) followed NHSN definitions. RESULTS: During the study period, there were 82 DAIs in adult ICUs and of these 16 (19.5%) were CLABSI, 26 (31.7%) were CAUTI and 40 (48.7%) were VAE. The overall rates for adult ICUs were 1.6, 1.9, 3.8 per 1000 device-days for CAUTI, CLABSI and VAE, respectively. The device-utilization ratio was 0.5, 0.6, and 0.48 for urinary catheters, central lines, and ventilators, respectively. VAE rates for medical and surgical ICU were about 2.8 times the rate in the coronary care unit and the rates were high in 2020 corresponding with the COVID-19 pandemic. Of the adult ICUS, medical ICU had a CLABSI rate of 2.13/1000 device-days and was about double the rate in surgical and cardiac ICU. For CAUTI, the rates per 1000 device-days were 2.19, 1.73, and 1.65 for medical, surgical, and coronary ICUs, respectively. The rate of CLABSI per 1000 device-days for pediatric and neonatal ICUs were 3.38 and 2.28, respectively. CONCLUSIONS: CAUTI was the most common infections among adult ICUs and medical ICU had higher rates than other adult ICUs. VAE rate was higher in the first year of the COVID-19 pandemic, indicating increased device-use, change in patients characteristics as well as possible change in practices across the ICUs.


Assuntos
COVID-19 , Infecções Relacionadas a Cateter , Infecção Hospitalar , Pneumonia Associada à Ventilação Mecânica , Infecções Urinárias , Adulto , Recém-Nascido , Humanos , Criança , Arábia Saudita/epidemiologia , Infecções Relacionadas a Cateter/epidemiologia , Pandemias , Estudos Prospectivos , Pneumonia Associada à Ventilação Mecânica/epidemiologia , COVID-19/epidemiologia , Infecção Hospitalar/epidemiologia , Unidades de Terapia Intensiva , Hospitais , Unidades de Terapia Intensiva Neonatal , Infecções Urinárias/epidemiologia
5.
J Hand Microsurg ; 13(2): 89-94, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33867767

RESUMO

Introduction Little and ring finger carpometacarpal joints (CMCJs) injuries are commonly missed due to misinterpretation of radiographs. We aimed to determine the sensitivity and specificity of four different radiographic views. Materials and Methods Radiographs (posteroanterior [PA], lateral [LAT], pronated oblique [POL], and supinated oblique [SOL] views) showing normal findings or little/ring finger CMCJ injuries were shown to two cohorts of orthopaedic trainees and a cohort of emergency nurse practitioners. Results The POL view performed best in all three testing scenarios. The SOL view performed least well. The combination of a PA, true LAT, and POL identified 78% of injuries correctly. In no cases did the SOL view correctly identify an injury when the other three views had been interpreted as normal. Conclusion We recommend a combination of the PA, POL, and LAT views in diagnosing these injuries. Where doubt remains, cross-sectional imaging is essential.

6.
Saudi J Biol Sci ; 28(4): 2466-2475, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33911960

RESUMO

The brown rat, Rattus norvegicus, is a model system in ecological and systematic science, but little is known about its skull morphology and developmental patterns. Our objective was to investigate the cranial ontogenetic patterns in the brown rats, from Hai'l, Kingdom of Saudi Arabia. Quantitative analysis of sexual shape dimorphisms (SShD) and age-classes were investigated using 28 landmarks plotted on two-dimensional images for dorsal and ventral views. Our results detected statistically significant sexual dimorphism (P-value <0.0001) in cranial shape and size for R. norvegicus. Nevertheless, males are much larger than females and display variation around the brain-case, while females tend to show greater variation around the occipital bone. In addition, there are subtle age-classes during ontogeny in the skull. However, the older age classes (i.e. age classes 3 and 4) represent well-built crania with an extended case of the brain and shortest nasal, while youngest specimens represent an elongated snout of minimum crania. Future GMM research should therefore examine the pre-defined age-classes and sex-related individuals in brown rat skulls in relation to genotype to characterize trends in skull shape variation that may affect teeth, zygomatic arches, brain case, and compartments of muscle attachments through its ecological patterns.

7.
Biosci. j. (Online) ; 36(6): 1930-1937, 01-11-2020. ilus
Artigo em Inglês | LILACS | ID: biblio-1147957

RESUMO

In the recent years, biochar has been used as an organic soil amendment. Therefore, this study was undertaken in April 2016 to July 2017 to examine the effect of different biochar addition (BA) rates and deficit irrigation (DI) on quality characteristics of cucumber under greenhouse conditions over two consecutive growing seasons. The BA treatments were B0 (0-ton ha-1), B1 (10-ton ha-1and B2 (20-ton ha-1), while the DI treatments were 1.0 (W1), 0.60 (W2) and 0.40 (W3) of the reference evapotranspiration (ET0). The results obtained elaborated that the combination of B2W1 gave the maximum values of fruit weight (g), fruit water content (%), fruit dry biomass (g) and pH in the both seasons. On the other hand, W2 and W3 increased significantly titratable acidity (TA %) and total soluble solid (TSS %). It was possible to conclude that BA with DI might be a novel approach to improve both crop yield and fruit quality.


Nos últimos anos, o biochar tem sido utilizado como uma alteração do solo orgânico. Desta maneira, este estudo foi realizado entre os períodos de Abril de 2016 a Julho de 2017 para investigar o efeito de diferentes taxas de alteração de biochar e irrigação por déficit (DI) nas características de qualidade do pepino em casa de vegetação durante duas safras consecutivas. Os tratamentos BA foram B0 (0 ton ha-1), B1 (10 ton ha-1 e B2 (20 ton ha-1), juntamente com três lâminas de irrigação em déficit W1, W2 e W3 correspondentes 100%, 60% e 40% da ET0, respectivamente. Os resultados obtidos mostraram que a combinação de B2W1 forneceu os valores máximos de peso dos frutos (g), teor de água dos frutos (%), biomassa seca dos frutos (g) e pH nas duas safras. Por outro lado, W2 e W3 aumentaram significativamente a acidez titulável (TA%) e o sólido solúvel total (TSS%). Foi possível concluir que a alteração de biochar com DI pode ser uma nova abordagem para melhorar tanto a produtividade como a qualidade dos frutos.


Assuntos
Cucumis sativus , Irrigação Agrícola
8.
J Wrist Surg ; 9(1): 2-12, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32025347

RESUMO

Background Scaphoid fractures represent less than 3% of hand and wrist fractures in the pediatric population. Nonunions are very rare. We present a case series ( n = 18) of nonunions in skeletally immature children and adolescents. We further present a review of the literature on pediatric scaphoid nonunions. Materials and Methods We reviewed the literature by searching the main databases on pediatric scaphoid nonunions, but to identify factors that lead to nonunion, we also searched for databases on scaphoid fractures. Seventy articles were found for the period between 1961 and 2019, all with level 4/5 evidence. Results The nonunion rate of pediatric scaphoid fractures in the literature is on average 1.5%, occurring mostly as a result of missed or underdiagnosed injuries, similar to our presented case series. Half ( n = 9) of the injuries in our case series were missed initial injuries, leading to scaphoid nonunions and half developed nonunions after initial treatment. We found excellent outcomes and with surgical and nonoperative management, with few complications. Not surprisingly, the duration of immobilization is longer with nonoperative management. Conclusions Based on the literature, we recommend a period of nonoperative management before surgery in undisplaced nonunions. In displaced nonunions, open reduction and internal fixation ± bone grafting is necessary. In pediatric scaphoid fractures, similar to adult cases, we identified that suspicious scaphoid fractures should be considered for initial immobilization, and repeat X-rays and early magnetic resonance imaging (MRI) or computed tomography (CT) scans should be considered at follow-up. Immobilization time and type of plaster should be appropriate in relation to the fracture site, similar to the adult scaphoid fracture. Level of Evidence This is a Level IV study.

9.
J Hand Surg Am ; 45(6): 557.e1-557.e5, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31585744

RESUMO

Cutibacterium (Propionibacterium) acnes (C. acnes, previously known as P. acnes) is an anaerobic organism that commonly colonizes the human skin. After Staphylococcus spp. and Streptococcus spp., it is a common organism associated with deep prosthetic shoulder joint infections. We describe the case of rapidly progressive arthropathy of the native wrist secondary to infection with C. acnes. Diagnosis was made on prolonged enrichment cultures. The patient went on to complete a long-term course of oral sulfamethoxazole-trimethoprim with clinical improvement. To the best of our knowledge, this is the first report in the literature that C. acnes has been the main causative organism implicated in infection of the native wrist joint. It is imperative to request and wait for results of prolonged enrichment cultures to aid microbiological diagnosis in such cases.


Assuntos
Artrite Infecciosa , Articulação do Ombro , Artrite Infecciosa/diagnóstico , Artrite Infecciosa/tratamento farmacológico , Humanos , Propionibacterium acnes , Ombro , Punho , Articulação do Punho
11.
J Foot Ankle Surg ; 57(4): 685-688, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29655649

RESUMO

The modified Broström technique (MBT) is considered the reference standard for surgical management of ankle instability, with good short-term outcomes. However, limited evidence is available regarding outcomes for delayed presentations of instability. We report our outcomes for patients who underwent ligament repair using the MBT, from a single-surgeon retrospective study of consecutive patients. The minimum postoperative follow-up period was 6 months during a 5-year study period. The patients were retrospectively divided into 3 groups according to the delay in presentation: group 1, 6 months to 2 years; group 2, 2 to 4 years; and group 3, >4 years. We collected data on patient demographics, injury pattern, and intraoperative surgeon findings. The American Orthopaedic Foot and Ankle Society (AOFAS) ankle-hindfoot scale (AHS) was used to evaluate patient outcomes and satisfaction with surgery. Twenty-six patients were treated with MBT. The mean follow-up period was 36.9 (range 6-42) months. Twenty-five (96.2%) patients had unilateral injuries, and 1 (3.85%) had bilateral repairs. Of the 26 patients, 21 (80.8%) completed the AOFAS-AHS, with a mean score of 87.4 (range 12 to 100). The mean interval from injury to surgery was 47.9 months. The results were excellent in 15 (71.4%), good in 3 (14.3%), fair in 1 (4.8%), and poor in 2 (9.5%) using the AOFAS-AHS. We found no significant difference in the overall AOFAS-AHS score or postoperative satisfaction among the groups (p > .05). All patients had a stable ankle joint at their final follow-up visit. In conclusion, patients with persistent or chronic ankle instability have good clinical outcomes and satisfaction after the MBT, irrespective of the time from injury to presentation.


Assuntos
Articulação do Tornozelo , Instabilidade Articular/cirurgia , Ligamentos Laterais do Tornozelo/cirurgia , Tempo para o Tratamento , Adolescente , Adulto , Doença Crônica , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Satisfação do Paciente , Reprodutibilidade dos Testes , Estudos Retrospectivos , Resultado do Tratamento , Adulto Jovem
12.
Artigo em Inglês | MEDLINE | ID: mdl-26893894

RESUMO

The RCS has published clear and succinct guidelines dictating the necessity for the documentation of legible and timely surgical operative notes and exactly what should be included. A baseline study within the upper limb unit at our trust showed a 71.1% adherence with the RCS guidelines with an average delay of typing of notes after dictation was 11.6 days. This quality improvement project designed and developed a bespoke electronic surgical notes template built within an existing database driven software within the Trust. After implementation of the templates we found no delays in full operative notes being typed and a 100% adherence with the RCS guidelines. This project significantly improved the quality and timely production of electronic surgical notes within a sustainable electronic software solution.

13.
Neuron ; 89(1): 163-76, 2016 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-26748091

RESUMO

Several neuropsychiatric disorders are associated with cognitive and social dysfunction. Postmortem studies of patients with schizophrenia have revealed specific changes in area CA2, a long-overlooked region of the hippocampus recently found to be critical for social memory formation. To examine how area CA2 is altered in psychiatric illness, we used the Df(16)A(+/-) mouse model of the 22q11.2 microdeletion, a genetic risk factor for developing several neuropsychiatric disorders, including schizophrenia. We report several age-dependent CA2 alterations: a decrease in the density of parvalbumin-expressing interneurons, a reduction in the amount of feedforward inhibition, and a change in CA2 pyramidal-neuron intrinsic properties. Furthermore, we found that area CA2 is less plastic in Df(16)A(+/-) mice, making it nearly impossible to evoke action potential firing in CA2 pyramidal neurons. Finally, we show that Df(16)A(+/-) mice display impaired social cognition, providing a potential mechanism and a neural substrate for this impairment in psychiatric disorders.


Assuntos
Potenciais de Ação/fisiologia , Síndrome de DiGeorge/fisiopatologia , Hipocampo/fisiopatologia , Neurônios/fisiologia , Envelhecimento , Animais , Transtornos Cognitivos/genética , Transtornos Cognitivos/fisiopatologia , Síndrome de DiGeorge/genética , Modelos Animais de Doenças , Hipocampo/patologia , Masculino , Memória/fisiologia , Camundongos Transgênicos , Parvalbuminas/genética , Esquizofrenia/genética , Esquizofrenia/fisiopatologia , Comportamento Social
14.
Nat Protoc ; 11(1): 61-86, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26658468

RESUMO

The normal heartbeat slightly fluctuates around a mean value; this phenomenon is called physiological heart rate variability (HRV). It is well known that altered HRV is a risk factor for sudden cardiac death. The availability of genetic mouse models makes it possible to experimentally dissect the mechanism of pathological changes in HRV and its relation to sudden cardiac death. Here we provide a protocol that allows for a comprehensive multilevel analysis of heart rate (HR) fluctuations. The protocol comprises a set of techniques that include in vivo telemetry and in vitro electrophysiology of intact sinoatrial network preparations or isolated single sinoatrial node (SAN) cells. In vitro preparations can be completed within a few hours, with data acquisition within 1 d. In vivo telemetric ECG requires 1 h for surgery and several weeks for data acquisition and analysis. This protocol is of interest to researchers investigating cardiovascular physiology and the pathophysiology of sudden cardiac death.


Assuntos
Eletrocardiografia/métodos , Fenômenos Eletrofisiológicos , Frequência Cardíaca , Telemetria/métodos , Potenciais de Ação , Animais , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Processamento de Sinais Assistido por Computador
16.
Nat Commun ; 5: 4699, 2014 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-25144390

RESUMO

Endolysosomal organelles play a key role in trafficking, breakdown and receptor-mediated recycling of different macromolecules such as low-density lipoprotein (LDL)-cholesterol, epithelial growth factor (EGF) or transferrin. Here we examine the role of two-pore channel (TPC) 2, an endolysosomal cation channel, in these processes. Embryonic mouse fibroblasts and hepatocytes lacking TPC2 display a profound impairment of LDL-cholesterol and EGF/EGF-receptor trafficking. Mechanistically, both defects can be attributed to a dysfunction of the endolysosomal degradation pathway most likely on the level of late endosome to lysosome fusion. Importantly, endolysosomal acidification or lysosomal enzyme function are normal in TPC2-deficient cells. TPC2-deficient mice are highly susceptible to hepatic cholesterol overload and liver damage consistent with non-alcoholic fatty liver hepatitis. These findings indicate reduced metabolic reserve of hepatic cholesterol handling. Our results suggest that TPC2 plays a crucial role in trafficking in the endolysosomal degradation pathway and, thus, is potentially involved in the homoeostatic control of many macromolecules and cell metabolites.


Assuntos
Canais de Cálcio/genética , Fígado Gorduroso/genética , Fígado Gorduroso/fisiopatologia , Animais , Transporte Biológico/genética , Cálcio/metabolismo , Canais de Cálcio/metabolismo , Colesterol/metabolismo , LDL-Colesterol/metabolismo , Endossomos/metabolismo , Receptores ErbB/metabolismo , Fígado Gorduroso/etiologia , Predisposição Genética para Doença , Lisossomos/metabolismo , Masculino , Camundongos Knockout
17.
Mol Biol Cell ; 25(6): 948-64, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24451262

RESUMO

The functional relationship between the formation of hundreds of fusion pores during the acrosome reaction in spermatozoa and the mobilization of calcium from the acrosome has been determined only partially. Hence, the second messenger NAADP, promoting efflux of calcium from lysosome-like compartments and one of its potential molecular targets, the two-pore channel 1 (TPC1), were analyzed for its involvement in triggering the acrosome reaction using a TPCN1 gene-deficient mouse strain. The present study documents that TPC1 and NAADP-binding sites showed a colocalization at the acrosomal region and that treatment of spermatozoa with NAADP resulted in a loss of the acrosomal vesicle that showed typical properties described for TPCs: Registered responses were not detectable for its chemical analogue NADP and were blocked by the NAADP antagonist trans-Ned-19. In addition, two narrow bell-shaped dose-response curves were identified with maxima in either the nanomolar or low micromolar NAADP concentration range, where TPC1 was found to be responsible for activating the low affinity pathway. Our finding that two convergent NAADP-dependent pathways are operative in driving acrosomal exocytosis supports the concept that both NAADP-gated cascades match local NAADP concentrations with the efflux of acrosomal calcium, thereby ensuring complete fusion of the large acrosomal vesicle.


Assuntos
Acrossomo/metabolismo , Canais de Cálcio/genética , Cálcio/metabolismo , Fertilidade , NADP/análogos & derivados , Reprodução , Acrossomo/efeitos dos fármacos , Reação Acrossômica/genética , Animais , Calcimicina/farmacologia , Canais de Cálcio/metabolismo , Carbolinas/farmacologia , Relação Dose-Resposta a Droga , Feminino , Deleção de Genes , Expressão Gênica , Genótipo , Heterozigoto , Homozigoto , Masculino , Camundongos , Camundongos Knockout , NADP/farmacologia , Piperazinas/farmacologia , Transdução de Sinais , Contagem de Espermatozoides
18.
Circulation ; 128(24): 2585-94, 2013 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-24218458

RESUMO

BACKGROUND: Sinus node dysfunction (SND) is a major clinically relevant disease that is associated with sudden cardiac death and requires surgical implantation of electric pacemaker devices. Frequently, SND occurs in heart failure and hypertension, conditions that lead to electric instability of the heart. Although the pathologies of acquired SND have been studied extensively, little is known about the molecular and cellular mechanisms that cause congenital SND. METHODS AND RESULTS: Here, we show that the HCN1 protein is highly expressed in the sinoatrial node and is colocalized with HCN4, the main sinoatrial pacemaker channel isoform. To characterize the cardiac phenotype of HCN1-deficient mice, a detailed functional characterization of pacemaker mechanisms in single isolated sinoatrial node cells, explanted beating sinoatrial node preparation, telemetric in vivo electrocardiography, echocardiography, and in vivo electrophysiology was performed. On the basis of these experiments we demonstrate that mice lacking the pacemaker channel HCN1 display congenital SND characterized by bradycardia, sinus dysrhythmia, prolonged sinoatrial node recovery time, increased sinoatrial conduction time, and recurrent sinus pauses. As a consequence of SND, HCN1-deficient mice display a severely reduced cardiac output. CONCLUSIONS: We propose that HCN1 stabilizes the leading pacemaker region within the sinoatrial node and hence is crucial for stable heart rate and regular beat-to-beat variation. Furthermore, we suggest that HCN1-deficient mice may be a valuable genetic disease model for human SND.


Assuntos
Modelos Animais de Doenças , Canais Disparados por Nucleotídeos Cíclicos Ativados por Hiperpolarização/deficiência , Canais de Potássio/deficiência , Síndrome do Nó Sinusal/fisiopatologia , Animais , Débito Cardíaco/fisiologia , Feminino , Frequência Cardíaca/fisiologia , Canais Disparados por Nucleotídeos Cíclicos Ativados por Hiperpolarização/genética , Canais Disparados por Nucleotídeos Cíclicos Ativados por Hiperpolarização/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Canais de Potássio/genética , Canais de Potássio/metabolismo , Nó Sinoatrial/metabolismo , Nó Sinoatrial/fisiopatologia
19.
Insect Sci ; 20(6): 717-22, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23955974

RESUMO

Sex ratio distortion in the tropical butterfly Acraea encedana is caused by infection with a male-killing bacterium of the genus Wolbachia. Previous research on this species has reported extreme female bias, high bacterial prevalences, and full sex role reversal. In this paper, we provide an assessment for the dynamics of the male-killer, based on a survey for sex ratios and Wolbachia prevalences among wild populations of A. encedana in Uganda. The study reveals that Wolbachia infection showed considerable variation over both spatial and temporal scales.


Assuntos
Borboletas/microbiologia , Interações Hospedeiro-Patógeno , Razão de Masculinidade , Wolbachia/fisiologia , Animais , Feminino , Masculino , Estações do Ano , Clima Tropical , Uganda
20.
Anat Sci Educ ; 6(3): 149-56, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23109285

RESUMO

Traditionally, an anatomy practical examination is conducted using a free response format (FRF). However, this format is resource-intensive, as it requires a relatively large time investment from anatomy course faculty in preparation and grading. Thus, several interventions have been reported where the response format was changed to a selected response format (SRF). However, validity evidence from those interventions has not proved entirely adequate for the practical anatomy examination, and thus, further investigation was required. In this study, the validity evidence of SRF was examined using multiple choice questions (MCQs) constructed according to different levels of Bloom's taxonomy in comparison with the traditional free response format. A group of 100 medical students registered in a gross anatomy course volunteered to be enrolled in this study. The experimental MCQ examinations were part of graded midterm and final steeplechase practical examination. Volunteer students were instructed to complete the practical examinations twice, once in each of two separate examination rooms. The two separate examinations consisted of a traditional free response format and MCQ format. Scores from the two examinations (FRF and MCQ) displayed a strong correlation, even with higher level Bloom's taxonomy questions. In conclusion, the results of this study provide empirical evidence that the SRF (MCQ) response format is a valid method and can be used as an alternative to the traditional FRF steeplechase examination.


Assuntos
Anatomia/educação , Avaliação Educacional/métodos , Automação , Feminino , Humanos , Masculino
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