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2.
Mymensingh Med J ; 29(1): 92-96, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31915342

RESUMEN

A cross sectional descriptive study was performed on 40 postmortem vermiform appendix (male 24 and female 16) to find out the diameter of lymphoid follicle of vermiform appendix of Bangladeshi people. The specimens were collected from autopsy laboratory of the Department of Forensic Medicine, Mymensingh Medical College, Mymensingh, Bangladesh by purposive sampling technique and were divided into four age groups. They were Group A (upto 20 years), Group B (21 to 40 years), Group C (41 to 60 years) and Group D (above 60 years). For this purpose, about 3mm long of whole thickness transverse section was taken from the middle of the vermiform appendix and thus the permanent slides were made for microscopic examination. To measure the diameter of the lymphoid follicle two measurements were taken. One was taken at the maximum diameter and another was perpendicular to it by ocular micrometer. Diameter of one largest and one smallest lymphoid follicles were measured and find out the mean diameter of lymphoid follicle between them. Diameter of lymphoid follicle = (Maximum transverse diameter + perpendicular diameter) /2. All data were recorded in the predesigned data sheet, analyzed by SPSS program (version 21, 2012) and compared with the findings of other national and international studies and standard text books. It was observed that diameter of lymphoid follicle of vermiform appendix gradually decreased as age advanced. The mean±SD diameter of lymphoid follicle was 580.31±37.07, 545.58±38.37, 485.68±40.20 and 428.12±68.41µm in Group A, B, C and D respectively. Statistical analysis shows that the mean differences of diameter of lymphoid follicle between A&B, C&D were statistically non significant at p= or >0.05 level, difference between Group B&C was statistically moderately significant at p<0.01 level and differences between Group A&C, B&D, A&D were statistically highly significant at p<0.001 level. Mean diameter of lymphoid follicle of vermiform appendix in male was higher (584.30±12.65µm in Group A, 549.42±38.36µm in Group B, 487.38±39.91µm in Group C, 430.68±70.30µm in Group D) than in female (576.31±53.77µm in Group A, 536.61±45.14µm in Group B, 483.14±46.68µm in Group C, 424.28±75.95µm in Group D) but mean difference between sexes in the different groups was statistically non significant at p=or >0.05 level. The present study will help to increase the information pool on the diameter of lymphoid follicle of vermiform appendix of Bangladeshi people.


Asunto(s)
Apéndice , Autopsia/métodos , Tejido Linfoide , Adulto , Factores de Edad , Anciano , Apéndice/anatomía & histología , Apéndice/patología , Grupo de Ascendencia Continental Asiática , Bangladesh , Cadáver , Estudios Transversales , Grupos Étnicos , Femenino , Humanos , Tejido Linfoide/anatomía & histología , Tejido Linfoide/patología , Masculino , Persona de Mediana Edad , Factores Sexuales , Adulto Joven
3.
Mymensingh Med J ; 29(1): 169-176, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31915354

RESUMEN

This cross sectional analytical type of study was conducted at department of Anatomy, Dhaka Medical College, Dhaka, Bangladesh from July 2015 to June 2016 on 50 adult Bangladeshi male sprinters (Group A) and 50 adult Bangladeshi male cricket batsman (Group B). Sample collection was done by convenient purposive sampling technique. History of any injury of hand during playing was excluded to construct standard measurement. Hand breadth was measured with the help of slide calipers. Hand grip strength Dynamometer was used to measure the hand grip strength. Paired Student's 't' test, unpaired student's 't' test and Pearson's correlation coefficient test were done for statistical analysis of the result. The aim of the present study was to determine hand breadth and average hand grip strength of Bangladeshi male cricket batsman to find out correlation between them that may be used as a baseline for other professions as well for future research in our country. The mean right and left hand grip strength was significantly higher in the cricket batsman than in the sprinters. The mean right and left hand breadth was found to be significantly higher in the cricket batsman than in the sprinters. Right and left hand grip strength showed significant positive correlation with hand breadth in both hand. The study findings suggest that regular physical exercise and training increase hand grip strength.


Asunto(s)
Fuerza de la Mano , Mano/anatomía & histología , Adulto , Animales , Antropometría , Grupo de Ascendencia Continental Asiática , Atletas , Bangladesh , Estudios Transversales , Grupos Étnicos , Humanos , Masculino , Dinamómetro de Fuerza Muscular , Carrera
5.
Saudi Med J ; 40(6): 601-609, 2019 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-31219496

RESUMEN

OBJECTIVE:  To explores cultural differences between generations of faculty and students in undergraduate medical education and to develop an educational framework for stakeholders involvement. METHODS:  This is a prospective cross-sectional mixed method study. A survey was administered on students and faculty members to measure generational differences using Hofstede's dimensions of cultural orientation. The study took place at King Abdulaziz University-Faculty of Medicine, Jeddah, Saudi Arabia, on February 2015. Quantitative methods, descriptive statistics, and correlations and regression analyses were used in data analysis. In addition, qualitative data from focus groups were used to explain findings obtained from the survey. RESULTS:  A total of 736 respondents were surveyed (129 faculty members and 607 medical students). Faculty members across all generations shared the same cultural values of low power distance and masculinity and high uncertainty avoidance, long-term orientation and collectivism. Advanced medical students showed higher power distance, collectivism, masculinity and long-term orientation than faculty members; junior medical students have higher masculinity and lower uncertainty avoidance and collectivism. CONCLUSION:  This study explains both the cultural gap between Saudi and Western medical students as well as between Saudi generations, demonstrating the need for customized curricular revisions.


Asunto(s)
Cultura , Educación de Pregrado en Medicina , Docentes/psicología , Relaciones Intergeneracionales , Estudiantes de Medicina/psicología , Estudios Transversales/métodos , Humanos , Modelos Lineales , Estudios Prospectivos , Arabia Saudita , Encuestas y Cuestionarios
6.
Int J Parasitol ; 49(6): 437-448, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-30910465

RESUMEN

Haemosporidian parasites of birds are ubiquitous in terrestrial ecosystems, but their coevolutionary dynamics remain poorly understood. If species turnover in parasites occurs at a finer scale than turnover in hosts, widespread hosts would encounter diverse parasites, potentially diversifying as a result. Previous studies have shown that some wide-ranging hosts encounter varied haemosporidian communities throughout their range, and vice-versa. More surveys are needed to elucidate mechanisms that underpin spatial patterns of diversity in this complex multi-host multi-parasite system. We sought to understand how and why a community of avian haemosporidian parasites varies in abundance and composition across elevational transects in eight sky islands in southwestern North America. We tested whether bird community composition, environment, or geographic distance explain haemosporidian parasite species turnover in a widespread host that harbors a diverse haemosporidian community, the Audubon's Warbler (Setophaga auduboni). We tested predictors of infection using generalized linear models, and predictors of bird and parasite community dissimilarity using generalized dissimilarity modeling. Predictors of infection differed by parasite genus: Parahaemoproteus was predicted by elevation and climate, Leucocytozoon varied idiosyncratically among mountains, and Plasmodium was unpredictable, but rare. Parasite turnover was nearly three-fold higher than bird turnover and was predicted by elevation, climate, and bird community composition, but not geographic distance. Haemosporidian communities vary strikingly at fine spatial scales (hundreds of kilometers), across which the bird community varies only subtly. The finer scale of turnover among parasites implies that their ranges may be smaller than those of their hosts. Avian host species should encounter different parasite species in different parts of their ranges, resulting in spatially varying selection on host immune systems. The fact that parasite turnover was predicted by bird turnover, even when considering environmental characteristics, implies that host species or their phylogenetic history plays a role in determining which parasite species will be present in a community.

7.
Life Sci Space Res (Amst) ; 20: 12-19, 2019 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-30797429

RESUMEN

BACKGROUND: Ionizing radiation and hypogravity can cause central nervous system (CNS) dysfunctions. This is a key limiting factor for deep space missions. Up until now, the mechanisms through which they affect the neural tissue are not completely understood. OBJECTIVES: We studied how the combination of hypogravity (antiorthostatic suspension model, AS) and ionizing radiations (γ-quanta and 1H+ together, R) affects the CNS. METHODS: We applied separately and in combination AS and R to determine the influence of these factors on behavior and metabolism of monoamines in Wistar rat's brain. RESULTS: We found out that R has a slight effect on both the behavior and metabolism of monoamines. However, when applied in combination with AS the former was able to reduce the negative effects of the latter. The combined effect of ionizing radiation and hypogravity led to the recovery of locomotor activity, orientation and exploratory behavior, and long-term context memory impaired under the impact of hypogravity only. These changes came together with an increase in the serotonin and dopamine turnover in all of the brain structures that were studied. CONCLUSIONS: We received the first evidence of interferential interaction between the effects of ionizing radiation and hypogravity factors with regard to a behavior and monoamine turnover in the brain. Further studies with heavy nuclei at relevant doses (<0.5 Gy) are needed.


Asunto(s)
Conducta Animal/efectos de la radiación , Monoaminas Biogénicas/metabolismo , Encéfalo/metabolismo , Hipogravedad , Modelos Biológicos , Radiación Ionizante , Animales , Encéfalo/efectos de la radiación , Masculino , Ratas , Ratas Wistar
8.
Phys Med ; 57: 7-16, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30738534

RESUMEN

Radiation protection of astronauts remains an ongoing challenge in preparation of deep space exploratory missions. Exposure to space radiation consisting of multiple radiation components is associated with a significant risk of experiencing central nervous system (CNS) detriments, potentially influencing the crew operational decisions. Developing of countermeasures protecting CNS from the deleterious exposure requires understanding the mechanistic nature of cognitive impairments induced by different components of space radiation. The current study was designed to identify differences in neurochemical modifications caused by exposure to low- and moderate-LET radiations and to elucidate a distinction between the observed outcomes. We exposed rats to accelerated protons (170 MeV; 0.5 keV/µm) or to carbon ions (12C; 500 MeV/u; 10.5 keV/µm) delivered at the same dose of 1 Gy. Neurochemical alterations were evaluated 1, 30, and 90 days after exposure via indices of the monoamine metabolism measured in five brain structures, including prefrontal cortex, hypothalamus, nucleus accumbens, hippocampus and striatum. We obtained the detailed patterns of neurochemical modifications after exposure to the mentioned radiation modalities. Our data show that the enhancement in the radiation LET from relatively low to moderate values leads to different neurochemical outcomes and that a particular effect depends on the irradiated brain structure. We also hypothesized that exposure to the moderate-LET radiations can induce a hyperactivation of feedback neurochemical mechanisms, which blur metabolic deviations and lead to the delayed impairments in brain functions. Based on our findings we discuss possible contribution of the observed changes to behavioural impairments.


Asunto(s)
Astronautas , Transferencia Lineal de Energía , Neuroquímica , Protección Radiológica , Animales , Encéfalo/metabolismo , Encéfalo/efectos de la radiación , Relación Dosis-Respuesta en la Radiación , Humanos , Masculino , Ratas , Ratas Sprague-Dawley
9.
Science ; 363(6425)2019 01 25.
Artículo en Inglés | MEDLINE | ID: mdl-30679341

RESUMEN

Species richness of marine mammals and birds is highest in cold, temperate seas-a conspicuous exception to the general latitudinal gradient of decreasing diversity from the tropics to the poles. We compiled a comprehensive dataset for 998 species of sharks, fish, reptiles, mammals, and birds to identify and quantify inverse latitudinal gradients in diversity, and derived a theory to explain these patterns. We found that richness, phylogenetic diversity, and abundance of marine predators diverge systematically with thermoregulatory strategy and water temperature, reflecting metabolic differences between endotherms and ectotherms that drive trophic and competitive interactions. Spatial patterns of foraging support theoretical predictions, with total prey consumption by mammals increasing by a factor of 80 from the equator to the poles after controlling for productivity.


Asunto(s)
Biodiversidad , Regulación de la Temperatura Corporal , Cadena Alimentaria , Metabolismo , Conducta Predatoria , Animales , Aves/fisiología , Peces/fisiología , Mamíferos/fisiología , Modelos Biológicos , Océanos y Mares , Filogenia , Reptiles/fisiología , Temperatura Ambiental
11.
FEMS Microbiol Ecol ; 94(11)2018 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-30165514

RESUMEN

Low biomass and productivity of arid-land caves with limited availability of nitrogen (N) raises the question of how microbes acquire and cycle this essential element. Caves are ideal environments for investigating microbial functional capabilities, as they lack phototrophic activity and have near constant temperatures and high relative humidity. From the walls of Fort Stanton Cave (FSC), multicolored secondary mineral deposits of soil-like material low in fixed N, known as ferromanganese deposits (FMD), were collected. We hypothesized that within FMD samples we would find the presence of microbial N cycling genes and taxonomy related to N cycling microorganisms. Community DNA were sequenced using Illumina shotgun metagenomics and 16S rRNA gene sequencing. Results suggest a diverse N cycle encompassing several energetic pathways including nitrification, dissimilatory nitrate reduction and denitrification. N cycling genes associated with assimilatory nitrate reduction were also identified. Functional gene sequences and taxonomic findings suggest several bacterial and archaeal phyla potentially play a role in nitrification pathways in FSC and FMD. Thaumarchaeota, a deep-branching archaeal division, likely play an essential and possibly dominant role in the oxidation of ammonia. Our results provide genomic evidence for understanding how microbes are potentially able to acquire and cycle N in a low-nutrient subterranean environment.


Asunto(s)
Archaea/metabolismo , Cuevas/microbiología , Ciclo del Nitrógeno/genética , Nitrógeno/metabolismo , Amoníaco/metabolismo , Archaea/genética , Archaea/aislamiento & purificación , Bacterias/genética , Bacterias/aislamiento & purificación , Bacterias/metabolismo , Desnitrificación , Metagenómica , New Mexico , Nitratos/metabolismo , Nitrificación , Oxidación-Reducción , ARN Ribosómico 16S/genética
13.
Brain ; 141(7): 1917-1933, 2018 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-29850777

RESUMEN

Cholinergic synapses are ubiquitous in the human central nervous system. Their high density in the thalamus, striatum, limbic system, and neocortex suggest that cholinergic transmission is likely to be critically important for memory, learning, attention and other higher brain functions. Several lines of research suggest additional roles for cholinergic systems in overall brain homeostasis and plasticity. As such, the brain's cholinergic system occupies a central role in ongoing research related to normal cognition and age-related cognitive decline, including dementias such as Alzheimer's disease. The cholinergic hypothesis of Alzheimer's disease centres on the progressive loss of limbic and neocortical cholinergic innervation. Neurofibrillary degeneration in the basal forebrain is believed to be the primary cause for the dysfunction and death of forebrain cholinergic neurons, giving rise to a widespread presynaptic cholinergic denervation. Cholinesterase inhibitors increase the availability of acetylcholine at synapses in the brain and are one of the few drug therapies that have been proven clinically useful in the treatment of Alzheimer's disease dementia, thus validating the cholinergic system as an important therapeutic target in the disease. This review includes an overview of the role of the cholinergic system in cognition and an updated understanding of how cholinergic deficits in Alzheimer's disease interact with other aspects of disease pathophysiology, including plaques composed of amyloid-ß proteins. This review also documents the benefits of cholinergic therapies at various stages of Alzheimer's disease and during long-term follow-up as visualized in novel imaging studies. The weight of the evidence supports the continued value of cholinergic drugs as a standard, cornerstone pharmacological approach in Alzheimer's disease, particularly as we look ahead to future combination therapies that address symptoms as well as disease progression.


Asunto(s)
Enfermedad de Alzheimer/metabolismo , Enfermedad de Alzheimer/fisiopatología , Neuronas Colinérgicas/fisiología , Enfermedad de Alzheimer/tratamiento farmacológico , Péptidos beta-Amiloides/metabolismo , Colinérgicos/metabolismo , Colinérgicos/uso terapéutico , Neuronas Colinérgicas/metabolismo , Inhibidores de la Colinesterasa/metabolismo , Cognición/fisiología , Trastornos del Conocimiento/etiología , Humanos , Ovillos Neurofibrilares/metabolismo
15.
Med Teach ; 40(sup1): S22-S29, 2018 09.
Artículo en Inglés | MEDLINE | ID: mdl-29703122

RESUMEN

PURPOSE: Prescription errors are a common cause of adverse drug events (ADEs). Recognizing ADEs can significantly contribute to the reduction of morbidity and mortality. This study aims to investigate the type and prevalence of errors in prescription writing, directed toward a needs assessment for developing educational interventions. MATERIALS AND METHODS: A cross-sectional descriptive study was conducted in Jeddah community pharmacies (January-February 2016). A random sample of 117 prescriptions were reviewed and analyzed by community pharmacists for legibility and omission of the information in the prescription. RESULTS: Results revealed that 51% of the prescriptions included diagnosis, in which 62% included the recommended drug dosage. Only 7% of drug interactions were reported between the prescribed drugs, 17% of the physicians prescribed drugs that prevented the adverse effects used for diagnosis. Prescriptions for chronic conditions were scrutinized to be 18%. It was noteworthy that 29% of the pharmacists reported difficulty in reading the handwriting of prescriptions. CONCLUSIONS: The quality of prescription writing is deficient in some elements and strategies for improvement are needed. These findings underscore a crucial requirement to upgrade the quality of prescription writing by encouraging continuous medical education programs to facilitate delivery of excellent therapeutic outcomes.


Asunto(s)
Prescripciones de Medicamentos/estadística & datos numéricos , Escritura Manual , Errores de Medicación/estadística & datos numéricos , Pautas de la Práctica en Medicina/estadística & datos numéricos , Estudios Transversales , Humanos , Prescripciones/estadística & datos numéricos , Prevalencia , Arabia Saudita
17.
Mol Neurobiol ; 55(4): 2991-3006, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-28456940

RESUMEN

Parkinson's disease (PD) is characterized by the appearance of motor symptoms many years after the onset of neurodegeneration, which explains low efficiency of therapy. Therefore, one of the priorities in neurology is to develop an early diagnosis and preventive treatment of PD, based on knowledge of molecular mechanisms of neurodegeneration and neuroplasticity in the nigrostriatal system. However, due to inability to diagnose PD at preclinical stage, research and development must be performed in animal models by comparing the nigrostriatal system in the models of asymptomatic and early symptomatic stages of PD. In this study, we showed that despite the progressive loss of neurons in the substantia nigra at the presymptomatic and symptomatic stage, almost no change was observed in the main functional characteristics of this brain region, including dopamine (DA) uptake and release, dopamine transporter (DAT) and vesicular monoamine transporter 2 (VMAT2) expression, and activity of MAO-A and MAO-B. In the striatum of presymptomatic mice, some parameters (DA release and uptake, MAO-A activity) remained compensatory unchanged or compensatory decreased (MAO-B gene expression and activity), while others-a reduction in DA levels in tissue and extracellular space and in VMAT2 and DAT expression-manifest the functional failure. In symptomatic mice, only a few parameters (spontaneous DA release and uptake, MAO-B gene expression and activity) remained at the same level as at presymptomatic stage, while most parameters (DA level in tissue and extracellular space, DA-stimulated release, VMAT2 and DAT contents), decreased, showing decompensation, which was enhanced by increasing MAO-A activity. Thus, this study provides a comprehensive assessment of the molecular mechanisms of neuroplasticity in 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine models of preclinical and clinical stages of PD, which could potentially serve as a powerful tool for translational medicine.


Asunto(s)
Enfermedad de Parkinson/patología , Investigación en Medicina Traslacional , 1-Metil-4-fenil-1,2,3,6-Tetrahidropiridina , Animales , Cuerpo Estriado/metabolismo , Cuerpo Estriado/patología , Modelos Animales de Enfermedad , Dopamina/metabolismo , Proteínas de Transporte de Dopamina a través de la Membrana Plasmática/genética , Proteínas de Transporte de Dopamina a través de la Membrana Plasmática/metabolismo , Masculino , Ratones Endogámicos C57BL , Monoaminooxidasa/genética , Monoaminooxidasa/metabolismo , Enfermedad de Parkinson/genética , Potasio/farmacología , ARN Mensajero/genética , ARN Mensajero/metabolismo , Sustancia Negra/metabolismo , Sustancia Negra/patología , Proteínas de Transporte Vesicular de Monoaminas/genética , Proteínas de Transporte Vesicular de Monoaminas/metabolismo
18.
Alzheimers Dement (Amst) ; 9: 84-87, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-29255790
19.
PeerJ ; 5: e3944, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-29093998

RESUMEN

Microorganisms that reside on and in mammals, such as bats, have the potential to influence their host's health and to provide defenses against invading pathogens. However, we have little understanding of the skin and fur bacterial microbiota on bats, or factors that influence the structure of these communities. The southwestern United States offers excellent sites for the study of external bat bacterial microbiota due to the diversity of bat species, the variety of abiotic and biotic factors that may govern bat bacterial microbiota communities, and the lack of the newly emergent fungal disease in bats, white-nose syndrome (WNS), in the southwest. To test these variables, we used 16S rRNA gene 454 pyrosequencing from swabs of external skin and fur surfaces from 163 bats from 13 species sampled from southeastern New Mexico to northwestern Arizona. Community similarity patterns, random forest models, and generalized linear mixed-effects models show that factors such as location (e.g., cave-caught versus surface-netted) and ecoregion are major contributors to the structure of bacterial communities on bats. Bats caught in caves had a distinct microbial community compared to those that were netted on the surface. Our results provide a first insight into the distribution of skin and fur bat bacteria in the WNS-free environment of New Mexico and Arizona. More importantly, it provides a baseline of bat external microbiota that can be explored for potential natural defenses against pathogens.

20.
Alzheimers Dement ; 2017 Oct 10.
Artículo en Inglés | MEDLINE | ID: mdl-29028480

RESUMEN

This article has been withdrawn at the request of the author(s) and/or editor. The Publisher apologizes for any inconvenience this may cause. The full Elsevier Policy on Article Withdrawal can be found at https://www.elsevier.com/about/our-business/policies/article-withdrawal.

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