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1.
Adv Med Educ Pract ; 15: 551-563, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38884014

RESUMO

Background: Formative assessment with feedback is part of the assessment program in medical education to improve students' learning. Limited research has focused on its application and impact on practical anatomy education. Methods: This study aimed to examine medical students' perceptions of formative assessment in practical anatomy sessions of body systems-based educational units and explore its influence on final practical exam performance. A descriptive, cross-sectional study was conducted. Data was collected from 173 Year 2 medical students through a survey that addressed their perception of process and importance of formative assessment and feedback. The survey employed a 5-point Likert scale. Two open-ended questions were appended at the end of the survey. Students' performance in Unit 3 (where formative assessment was conducted) was compared to their performance in Unit 2 (where no formative assessment was conducted) and with the performance of the previous academic year's students in Unit 3 (where no formative assessment was conducted). Descriptive statistics were used. The level of statistical significance was set at p-value < 0.05. Responses to open-ended questions (qualitative data) were counted, categorized as themes, and presented as frequencies and percentages. Results: The survey showed high internal consistency, and its validity was established through exploratory factor analysis. Results showed that the mean mark for the unit with formative assessment and feedback was significantly higher than for the units without formative assessment and feedback. Students showed positive perception of formative assessment and feedback conducted after practical anatomy sessions. They reported useful insights regarding the benefits they gained from formative assessment and feedback as well as constructive suggestions for future improvements. Conclusion: The study indicates that students positively perceived formative assessment and feedback sessions after practical anatomy sessions. Findings also refer to a positive effect of formative assessment on students' performance in summative practical assessment in anatomy.

2.
Cell Tissue Res ; 392(2): 443-466, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36577880

RESUMO

Type 2 diabetes (T2D) is implicated in the injury of several organs, including the brain resulting in neuronal damage, which may lead to cognitive impairment and dementia. Additionally, it is linked to inflammation, cytokine release, apoptosis and various degenerative conditions. Astrocytes and microglia might have a role in mediating these processes. Caffeine, a psychoactive beverage, has been shown to reduce the risk of cognitive and memory impairment. This study proposes anti-inflammatory and anti-apoptotic role of caffeine, which can be mediated via microglia/astrocyte activation and overexpression of pro-inflammatory molecules. T2D was induced in rats by feeding with high fat high sugar diet and injecting a single low dose streptozotocin (STZ) intraperitoneally. Other diabetic rats were given caffeine orally (in two doses) for 5 weeks, starting 1 week before STZ injection. Measurement of plasma cytokines, TNFα and IL6, was performed using enzyme-linked immunosorbent assay (ELISA) technique. After sacrificing animals, brains were obtained and processed for histological evaluation. Immunohistochemistry was also performed using the following primary antibodies, anti-astrocyte marker GFAP, anti-microglia marker CD11b and apoptotic marker (anti-cleaved caspase-3). There was upregulation of IL6 and TNF-α in diabetic rats. Additionally, histological evaluation of the hippocampus of diabetic rats revealed cellular degeneration. There was increased immunostaining of GFAP, CD11b and cleaved caspase-3 in diabetic rats. Pretreatment with caffeine to diabetic rats, resulted in improvement of structural changes and decrease in cytokine levels and immuno-markers, expression, and this was in a dose-dependent manner. In conclusion, caffeine had an ameliorative role in enhancing hippocampal degenerative changes in T2D.


Assuntos
Diabetes Mellitus Experimental , Diabetes Mellitus Tipo 2 , Ratos , Animais , Cafeína/farmacologia , Cafeína/uso terapêutico , Cafeína/metabolismo , Diabetes Mellitus Experimental/metabolismo , Caspase 3/metabolismo , Diabetes Mellitus Tipo 2/complicações , Interleucina-6/metabolismo , Gliose/patologia , Inflamação/patologia , Citocinas/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Apoptose , Hipocampo/metabolismo
3.
Anat Rec (Hoboken) ; 304(4): 787-802, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33015986

RESUMO

Intervertebral disc degeneration (IVDD) is a major contributor to low back pain (LBP). Granulocyte-colony stimulating factor (GCSF) is known to mobilize hematopoietic stem cells (HSCs) that may be implicated in intervertebral disc (IVD) regeneration. Rats were divided into the following three groups: (i) control group; (ii) IVDD group-the rats underwent Co5/Co6 and Co7/Co8 IVDD operation; and (iii) GCSF-treated group-the rats received daily GCSF subcutaneous injections starting 6 weeks after the IVDD operation and continued for 5 days. All of the rats were euthanized after 8 weeks, and IVDs were assessed by tail X-ray and histopathological, immunohistochemical, and transmission electron microscopy (TEM) analyses. The X-rays showed disc narrowing in the IVDD group that was significantly widened in the GCSF-treated rats. Histologically, the IVDD group showed disarrangement of the annulus fibrosis lamellae, complete degeneration of the nucleus pulposus, and loss of proteoglycan content. These changes were improved after GCSF treatment. Vertebral endplate thickness and cellularity were significantly decreased with IVDD and significantly increased after GCSF treatment. Stromal cell-derived factor-1α (SDF-1α) immune expression was significantly increased in the IVDD group but decreased in the GCSF-treated group. However, the caspase-3 expression percentage showed no significant difference among the studied groups. TEM showed excessive collagen deposits around the notochordal cells in the IVDD group, which were attenuated in the GCSF-treated group. These results indicate that GCSF improves IVDD and promotes its recovery based on radiological, histological and TEM findings.


Assuntos
Fator Estimulador de Colônias de Granulócitos e Macrófagos/uso terapêutico , Degeneração do Disco Intervertebral/tratamento farmacológico , Disco Intervertebral/efeitos dos fármacos , Animais , Modelos Animais de Doenças , Fator Estimulador de Colônias de Granulócitos e Macrófagos/farmacologia , Disco Intervertebral/diagnóstico por imagem , Disco Intervertebral/patologia , Degeneração do Disco Intervertebral/diagnóstico por imagem , Degeneração do Disco Intervertebral/patologia , Masculino , Núcleo Pulposo/patologia , Radiografia , Ratos , Ratos Sprague-Dawley
4.
Tissue Cell ; 65: 101366, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32746983

RESUMO

Thyroid hormones are essential for metabolic rate regulation and play a role on the integrity of the salivary glands. Nigella sativa is a widely used plant in medicine. This study aimed to evaluate the effect of Nigella sativa oil (NSO) on the hypothyroidism-induced parotid gland pathological alterations. Rats were divided into four groups: control group, hypothyroid group: received daily oral carbimazole for 3 weeks, hypothyroid-NSO group: NSO was orally given for 4 weeks after hypothyroidism induction and NSO group: administrated NSO only for 4 weeks. After 7 weeks, all rats were sacrificed, serum thyroid hormones were estimated, and parotid glands were assessed by histopathological, immunohistochemical, ultrastructural and morphometric analyses. Hypothyroid group showed a significant decrease in thyroid hormones with increase in thyroid-stimulating hormone (TSH) levels and decrease in body and parotid weights compared to the control rats that were improved with NSO treatment. Sections of the hypothyroid group showed fibrosis, acinar cytoplasmic vacuolations, vascular congestion, ductal dilatation, wide intercellular canaliculi, nuclear pyknosis and decreased number of secretory granules. Also, there were decreased B-cell lymphoma 2 (Bcl-2) and increased p53, Bcl-2 Associated X (Bax) and alpha-smooth muscle actin (α-SMA) immune-expressions; with decreased Bax/ Bcl-2 ratio that all were attenuated by NSO. NSO ameliorates hypothyroidism-induced parotid changes by altering p53, Bax and Bcl-2 pathway.


Assuntos
Hipotireoidismo/tratamento farmacológico , Hipotireoidismo/patologia , Glândula Parótida/patologia , Óleos de Plantas/uso terapêutico , Animais , Peso Corporal/efeitos dos fármacos , Hipotireoidismo/sangue , Masculino , Tamanho do Órgão/efeitos dos fármacos , Glândula Parótida/efeitos dos fármacos , Glândula Parótida/ultraestrutura , Óleos de Plantas/farmacologia , Ratos Sprague-Dawley
5.
Rom J Morphol Embryol ; 60(1): 145-158, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31263839

RESUMO

Benign prostatic hyperplasia (BPH) is a common aging disease in men. Garlic is known to have anti-proliferative effects. Therefore, this study was designed to investigate the curative and preventive effects of garlic on BPH in rats. Rats were divided into five groups: control group, orchiectomized group (where rats were subjected to bilateral orchiectomies operation), BPH group [BPH was induced by intramuscular injection of testosterone (TE) enanthate once weekly for five weeks after orchiectomy], curative group (where rats were injected with TE for five weeks followed by daily administration of garlic powder for other five weeks), and preventive group (where rats were given garlic powder simultaneously with TE injections for five weeks). Serum levels of TE and prostate-specific antigen (PSA) were measured, and prostate weighed and processed for light microscopic, immunohistochemical and transmission electron microscopy (TEM) examination. Serum levels of TE and PSA, and prostate weight (PW) were significantly increased in BPH group and significantly decreased in curative and preventive ones. Histologically and morphometrically, BPH group showed epithelial hyperplasia, stromal expansion and reduced acinar lumens that were significantly improved in both curative and preventive groups. Proliferating cell nuclear antigen (PCNA) expression was increased while caspase-3 expression was decreased in BPH group. These results were reversed in both curative and preventive groups. TEM showed nuclear irregularities, dilated endoplasmic reticulum (ER) cisterns, and lost cell boundaries, secretory vesicles and apical microvilli. Most of the previous changes were minimized in preventive group more than in curative one.


Assuntos
Alho/química , Hiperplasia Prostática/prevenção & controle , Testosterona/efeitos adversos , Animais , Masculino , Hiperplasia Prostática/tratamento farmacológico , Ratos , Ratos Sprague-Dawley
6.
J Chem Neuroanat ; 98: 139-152, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31047945

RESUMO

BACKGROUND: Stem cells therapy of hearing loss is a challenging field due to lacking self-regenerative capacity of cochlea. Harderian gland of guinea pigs was thought to harbour a unique type of progenitors which could restore the damaged cochlear tissues. THE AIM: of this study was to isolate Harderian gland derived stem cells (HG-SCs) and investigate their efficacy in restoring the damaged cochlear tissue in carboplatin-induced hearing loss. METHODOLOGY: Sixty female and 10 male pigmented guinea pigs were used; the male animals were HG-SCs donors, while the females were assigned into 3 groups; control, hearing loss (HL) and HG-SC-treated groups. Auditory reflexes were assessed throughout the study. The animals were euthanized 35 days after HG-SCs transplantation, the cochleae were extracted and processed for assessment by light microscope and scanning electron microscope. Morphometric assessment of stria vascularis thickness, hair cells and spiral ganglia neuronal number and optical density of TLR4 expression were done. RESULTS: The isolated HG-SCs had the same morphological and phenotypical character as mesenchymal stem cells. HL group revealed destruction of organ of Corti, stria vascularis and spiral ganglion with decreased morphometric parameters. Restoration of both cochlear structure and function was observed in HG-SC-treated group along with a significant increase in IHCs, OHCs numbers, stria vascularis thickness and spiral ganglionic cell count to be close to the values of control group. CONCLUSION: The isolated HG-SCs were proved to restore structure and function of cochlea in guinea pig model of hearing loss.


Assuntos
Antineoplásicos/toxicidade , Carboplatina/toxicidade , Glândula de Harder/citologia , Perda Auditiva Neurossensorial/induzido quimicamente , Transplante de Células-Tronco/métodos , Animais , Separação Celular , Modelos Animais de Doenças , Feminino , Cobaias , Perda Auditiva Neurossensorial/terapia , Masculino
7.
Eur. j. anat ; 22(4): 345-354, jul. 2018. ilus, tab
Artigo em Inglês | IBECS | ID: ibc-179098

RESUMO

Gibberellic acid (GA3) is a plant growth regulator, widely used in agriculture in Egypt. The goal of this study was to illustrate the histopathological effects of (GA3) on the growing cerebellar cortex and the possible ameliorative effect of vitamin C. Fifty female Sprague-Dawly rats were classified into the following groups: Group I (control group); Group II (GA3-treated group), which received intra-gastric daily dose of GA3 55 mg/kg from the 14th day of pregnancy until the day 14 after delivery; Group III (GA3 & Vitamin C treated group), which received intra-gastric daily dose GA3, 55 mg/kg simultaneously with 100 mg of Vitamin C /kg from the 14th day of pregnancy till day 14 after delivery; and Group IV (Vitamin C-treated group), which received intra-gastric daily dose 100 mg of Vitamin C / kg from the 14th day of pregnancy till day 14 after delivery. One month after delivery, cerebella of pups from all groups were extracted and examined. The cerebellar cortex of GA3-treated group revealed degenerated and displaced Purkinje and granular nerve cells with prominent spongiosis in the molecular layer. Vitamin C administration resulted in marked regression of the previously mentioned neurotoxic effects. In conclusion: results of the current study revealed that maternal exposure to GA3 during pregnancy and lactation caused delayed development of the offsprings' cerebellar cortex. The co-administration of Vitamin C greatly reduced these neuro-toxic effects of GA3 exposure


No disponible


Assuntos
Animais , Ratos , Gravidez , Giberelinas/toxicidade , Córtex Cerebelar/anatomia & histologia , Ácido Ascórbico/uso terapêutico , Albinismo , Giberelinas , Córtex Cerebelar/crescimento & desenvolvimento , Córtex Cerebelar/fisiopatologia , Gravidez/fisiologia , Gravidez/metabolismo
8.
Biomed Pharmacother ; 103: 1178-1186, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29864896

RESUMO

BACKGROUND: Olfactory stem cells (OSCs) are found in the olfactory mucosa and olfactory bulb and have the capacity to proliferate and differentiate along multiple tissue lineages. Rotenone; widely used insecticide has a neurodegenerative effect on the dopaminergic cells of substantia nigra (SN) of midbrain producing Parkinsonism. The aim of this study is to isolate rat OSCs from olfactory mucosa and olfactory bulb, culture these OSCs in suitable medium to allow for their proliferation to be used in the treatment of Parkinsonism induced by rotenone. METHODS: The characteristics of OSCs, the effects of rotenone on the SN of midbrain and the curative effect of OSCs on the substantia nigra were determined morphologically, immunohistochemically, and by transmission electron microscopy. PKH 26; immunofluorescent dye was used as a cell tracer to locate the transplanted cells in host midbrain. RESULTS: OSCs were spindle shaped with irregular processes, and were positive for CD44 and Nestin and negative for CD34. Subcutaneous rotenone produced Parkinsonism through producing degeneration of the dopaminergic cells of SN of the midbrain. Transplantation of OSCs produced restoration of the normal structure of SN and dopaminergic cells and improves the clinical manifestations of Parkinsonism. CONCLUSION: These results indicate that, the isolated rat OSCs can proliferate and expand in vitro when culture in suitable medium and these cells can exert therapeutic effects in Parkinsonism by recruitment in SN and restoration of the structure and function of dopaminergic cells.


Assuntos
Envelhecimento/patologia , Bulbo Olfatório/citologia , Transtornos Parkinsonianos/terapia , Transplante de Células-Tronco , Células-Tronco/citologia , Animais , Células Cultivadas , Masculino , Mesencéfalo/patologia , Mesencéfalo/ultraestrutura , Atividade Motora , Transtornos Parkinsonianos/induzido quimicamente , Transtornos Parkinsonianos/patologia , Transtornos Parkinsonianos/fisiopatologia , Ratos , Rotenona , Resultado do Tratamento , Tirosina 3-Mono-Oxigenase/metabolismo
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