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1.
J Pharmacol Exp Ther ; 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38955492

RESUMO

Oxidative stress, fibrosis, and inflammasome activation from AGE-RAGE interaction contribute to diabetic cardiomyopathy (DCM) formation and progression. Our study revealed the impact of ß-caryophyllene (BCP) on activating CB2 receptors against diabetes complications and investigated the underlying cell signaling pathways in mice. The murine model of DCM was developed by feeding high-fat diet with streptozotocin injections. After the development of diabetes, the animals received a 12-week oral BCP treatment at a dosage of 50 mg/kg/body weight. BCP treatment showed significant improvement in glucose tolerance, insulin resistance, and enhanced serum insulin levels in diabetic animals. BCP treatment effectively reversed the heart remodeling and restored the phosphorylated troponin I and SERCA2a expression. Ultrastructural examination showed reduced myocardial cell injury in DCM mice treated with BCP. The preserved myocytes were found associated with reduced expression of AGE/RAGE in DCM mice hearts. BCP treatment mitigated oxidative stress by inhibiting expression of NOX4 and activating PI3K/AKT/Nrf2 signaling. BCP suppressed cardiac fibrosis and endothelial-to-mesenchymal transition (EndMT) in DCM mice by inhibiting TGF-ß/Smad signaling. Further, BCP treatment suppressed NLRP3 inflammasome activation in DCM mice and alleviated cellular injury to the pancreatic tissues evidenced by significant elevation of the number of insulin-positive cells. To demonstrate CB2 receptor dependent mechanism of BCP, another group of DCM mice were pretreated with AM630, a CB2 receptor antagonist AM630 and AM630 was observed to abrogate the beneficial effects of BCP in DCM mice. Taken together, BCP showed the potential to protect the myocardium and pancreas of DCM mice mediating CB2 receptor dependent mechanisms. Significance Statement 1. ß-caryophyllene (BCP), a cannabinoid type 2 receptor (CB2R) agonist. 2. BCP attenuates diabetic cardiomyopathy via activating CB2R in mice 3. CB2R activation by BCP shows strong protection against fibrosis and inflammasome activation 4. It regulates AGE/RAGE and PI3K/Nrf2/Akt signaling in mice.

2.
Int J Mol Sci ; 24(2)2023 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-36674739

RESUMO

Sirolimus (SRL) is widely used as an immunosuppressant to prevent graft rejection, despite the risk of impairing glucose metabolism. Metformin (MET) can reduce the detrimental effects of SRL in many patients, including diabetes and renal transplant recipients. Limited in vivo studies have reported on SRL and MET therapy, particularly in relation to cellular bioenergetics, glucose metabolism, and insulin resistance. Herein, we investigated the efficacy of SRL and MET co-treatment in BALB/c mice over 4 weeks. Balb/c mice (4-6 weeks old) were divided into four groups and injected intraperitoneally (i.p.) with water (control, CTRL), MET (200 µg/g), SRL (5 µg/g), or MET (200 µg/g) +SRL (5 µg/g) over a period of one month. We evaluated the body weight, food consumption rate, random blood glucose (BG), insulin levels, serum biochemistry parameters (ALT, Albumin, BUN, Creatinine), and histomorphology in all groups using standardized techniques and assays. All drug-treated groups showed a statistically significant decrease in weight gain compared to the CTRL group, despite normal food intake. Treatment with SRL caused elevated BG and insulin levels, which were restored with SRL + MET combination. Serum biochemical parameters were within the normal range in all the studied groups. SRL+ MET co-treatment decreased liver cellular respiration and increased cellular ATP levels in the liver. In the pancreas, co-treatment resulted in increased cellular respiration and decreased cellular ATP levels. Liver and pancreatic histology were unchanged in all groups. This study showed that co-treatment of SRL with MET alleviates hyperglycemia induced by SRL without any deleterious effects. These results provide initial insights into the potential use of SRL + MET therapy in various settings.


Assuntos
Hiperglicemia , Insulinas , Metformina , Animais , Camundongos , Sirolimo/farmacologia , Metformina/farmacologia , Camundongos Endogâmicos BALB C , Imunossupressores , Hiperglicemia/tratamento farmacológico , Hiperglicemia/induzido quimicamente , Respiração Celular , Glucose , Trifosfato de Adenosina , Rejeição de Enxerto/tratamento farmacológico , Rejeição de Enxerto/prevenção & controle
3.
Int J Mol Sci ; 24(18)2023 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-37762315

RESUMO

Cancer chemotherapy with doxorubicin (DOX) may have multiorgan toxicities including cardiotoxicity, and this is one of the major limitations of its clinical use. The present study aimed to evaluate the cardioprotective role of α-Bisabolol (BSB) in DOX-induced acute cardiotoxicity in rats and the underlying pharmacological and molecular mechanisms. DOX (12.5 mg/kg, single dose) was injected intraperitoneally into the rats for induction of acute cardiotoxicity. BSB was given orally to rats (25 mg/kg, p.o. twice daily) for a duration of five days. DOX administration induced cardiac dysfunction as evidenced by altered body weight, hemodynamics, and release of cardio-specific diagnostic markers. The occurrence of oxidative stress was evidenced by a significant decline in antioxidant defense along with a rise in lipid peroxidation and hyperlipidemia. Additionally, DOX also increased the levels and expression of proinflammatory cytokines and inflammatory mediators, as well as activated NF-κB/MAPK signaling in the heart, following alterations in the Nrf2/Keap-1/HO-1 and Akt/mTOR/GSK-3ß signaling. DOX also perturbed NLRP3 inflammasome activation-mediated pyroptosis in the myocardium of rats. Furthermore, histopathological studies revealed cellular alterations in the myocardium. On the contrary, treatment with BSB has been observed to preserve the myocardium and restore all the cellular, molecular, and structural perturbations in the heart tissues of DOX-induced cardiotoxicity in rats. Results of the present study clearly demonstrate the protective role of BSB against DOX-induced cardiotoxicity, which is attributed to its potent antioxidant, anti-inflammatory, and antihyperlipidemic effects resulting from favorable modulation of numerous cellular signaling regulatory pathways, viz., Nrf2/Keap-1/HO-1, Akt/mTOR/GSK-3ß, NF-κB/p38/MAPK, and NLRP3 inflammasomes, in countering the cascades of oxidative stress and inflammation. The observations suggest that BSB can be a promising agent or an adjuvant to limit the cardiac injury caused by DOX. Further studies including the role in tumor-bearing animals as well as regulatory toxicology are suggested.

4.
Molecules ; 28(6)2023 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-36985728

RESUMO

Toxic chemicals such as carbon tetrachloride and thioacetamide (TAA) are reported to induce hepato-nephrotoxicity. The potential protective outcome of the antidiabetic and pleiotropic drug metformin against TAA-induced chronic kidney disease in association with the modulation of AMP-activated protein kinase (AMPK), oxidative stress, inflammation, dyslipidemia, and systemic hypertension has not been investigated before. Therefore, 200 mg/kg TAA was injected (via the intraperitoneal route) in a model group of rats twice a week starting at week 3 for 8 weeks. The control rats were injected with the vehicle for the same period. The metformin-treated group received 200 mg/kg metformin daily for 10 weeks, beginning week 1, and received TAA injections with dosage and timing similar to those of the model group. All rats were culled at week 10. It was observed that TAA induced substantial renal injury, as demonstrated by significant kidney tissue damage and fibrosis, as well as augmented blood and kidney tissue levels of urea, creatinine, inflammation, oxidative stress, dyslipidemia, tissue inhibitor of metalloproteinases-1 (TIMP-1), and hypertension. TAA nephrotoxicity substantially inhibited the renal expression of phosphorylated AMPK. All these markers were significantly protected by metformin administration. In addition, a link between kidney fibrosis and these parameters was observed. Thus, metformin provides profound protection against TAA-induced kidney damage and fibrosis associated with the augmentation of the tissue protective enzyme AMPK and inhibition of oxidative stress, inflammation, the profibrogenic gene TIMP-1, dyslipidemia, and hypertension for a period of 10 weeks in rats.


Assuntos
Dislipidemias , Hipertensão , Metformina , Insuficiência Renal Crônica , Ratos , Animais , Metformina/farmacologia , Metformina/uso terapêutico , Proteínas Quinases Ativadas por AMP/metabolismo , Tioacetamida/toxicidade , Inibidor Tecidual de Metaloproteinase-1/metabolismo , Regulação para Cima , Regulação para Baixo , Estresse Oxidativo , Inflamação/metabolismo , Insuficiência Renal Crônica/metabolismo , Fibrose , Hipertensão/induzido quimicamente , Hipertensão/tratamento farmacológico , Hipertensão/metabolismo , Dislipidemias/induzido quimicamente , Dislipidemias/tratamento farmacológico , Dislipidemias/metabolismo , Fígado/metabolismo , Cirrose Hepática/tratamento farmacológico
5.
Int J Mol Sci ; 23(18)2022 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-36142441

RESUMO

Doxorubicin (DOX) is a well-known and effective antineoplastic agent of the anthracycline family. But, multiple organ toxicities compromise its invaluable therapeutic usage. Among many toxicity types, nephrotoxicity is one of the major concerns. In recent years many approaches, including bioactive agents of natural origin, have been explored to provide protective effects against chemotherapy-related complications. α-Bisabolol is a naturally occurring monocyclic sesquiterpene alcohol identified in the essential oils of various aromatic plants and possesses a wide range of pharmacological properties such as antioxidant, anti-inflammatory, analgesic, cardioprotective, antibiotic, anti-irritant, and anticancer activities. The present study aimed to evaluate the effects of α-Bisabolol on DOX-induced nephrotoxicity in Wistar male albino rats. Nephrotoxicity was induced in rats by injecting a single dose of DOX (12.5 mg/kg, i.p.), and the test compound, α-Bisabolol (25 mg/kg) was administered intraperitoneally along with DOX as a co-treatment daily for 5 days. DOX-injected rats showed reduction in body weight along with a concomitant fall in antioxidants and increased lipid peroxidation in the kidney. DOX-injection also increased levels/expressions of proinflammatory cytokines namely tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), and interleukin-1ß (IL-1ß) and inflammatory mediators like inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) and activated nuclear factor kappa-B (NF-κB)/mitogen-activated protein kinases (MAPK) signaling in the kidney tissues. DOX also triggered apoptotic cell death, evidenced by the increased expression of pro-apoptotic markers like BCL2-Associated X Protein (Bax), cleaved caspase-3, caspase- 9, and cytochrome-C) and a decrease in the expressions of anti-apoptotic markers namely B-cell lymphoma 2 (Bcl2) and B-cell lymphoma-extra large (Bcl-xL) in the kidney. These biochemical alterations were additionally supported by light microscopic findings, which revealed structural alterations in the kidney. However, treatment with α-Bisabolol prevented body weight loss, restored antioxidants, mitigated lipid peroxidation, and inhibited the rise in proinflammatory cytokines, as well as favorably modulated the expressions of NF-κB/MAPK signaling and apoptosis markers in DOX-induced nephrotoxicity. Based on the results observed, it can be concluded that α-Bisabolol has potential to attenuate DOX-induced nephrotoxicity by inhibiting oxidative stress and inflammation mediated activation of NF-κB/MAPK signaling alongwith intrinsic pathway of apoptosis in rats. The study findings are suggestive of protective potential of α-Bisabolol in DOX associated nephrotoxicity and this could be potentially useful in minimizing the adverse effects of DOX and may be a potential agent or adjuvant for renal protection.


Assuntos
NF-kappa B , Óleos Voláteis , Animais , Antibacterianos/farmacologia , Antibióticos Antineoplásicos/farmacologia , Antioxidantes/metabolismo , Antioxidantes/farmacologia , Apoptose , Caspase 3/metabolismo , Ciclo-Oxigenase 2/metabolismo , Citocromos/metabolismo , Doxorrubicina/toxicidade , Mediadores da Inflamação/farmacologia , Interleucina-1beta/metabolismo , Interleucina-6/metabolismo , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Sesquiterpenos Monocíclicos , NF-kappa B/metabolismo , Óxido Nítrico Sintase Tipo II/metabolismo , Óleos Voláteis/farmacologia , Ratos , Ratos Wistar , Fator de Necrose Tumoral alfa/metabolismo , Proteína X Associada a bcl-2/metabolismo
6.
Am J Physiol Renal Physiol ; 319(5): F833-F838, 2020 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-33017190

RESUMO

Angiotensin II drives the pathogenesis of diabetic kidney disease, and its systemic administration induces glomerular hyperpermeability in normal rats. However, the response of diabetic glomerular permeability to angiotensin II is largely unknown. In the present study, we investigated the impact of extended systemic administration of angiotensin II on the glomerular permeability of streptozotocin (STZ)-induced late diabetes in rats. We examined the changes in the glomerular permeability after subcutaneous infusion of angiotensin II at 200 ng·kg-1·min-1 for 7 days in male Wistar diabetic rats with 3 mo of STZ-induced diabetes (i.e., blood glucose of ∼20 mmol/L). We also compared these changes with the effects on nondiabetic rats. The sieving coefficients (θ) for inert polydisperse Ficoll molecules, which had a radius of 10-90 Å (Ficoll70-90 Å), were measured in vivo. The θ for large Ficoll molecules was selectively enhanced after infusion of extended angiotensin II in both diabetic (θ for Ficoll70-90 Å = 0.00244 vs. 0.00079, P < 0.001) and nondiabetic animals (θ for Ficoll70-90 Å = 0.00029 vs. 0.00006, P < 0.001). These changes were compatible with the more than twofold increase in the macromolecular glomerular transport through the large-pore pathways after infusion of angiotensin II in both diabetic and nondiabetic animals. Angiotensin II infusion enhanced the large shunt-like glomerular transport pathway of STZ-induced late diabetes. Such defects can account for the large-molecular-weight IgM-uria that is observed in severe diabetic kidney disease.


Assuntos
Angiotensina II/farmacologia , Diabetes Mellitus Experimental/tratamento farmacológico , Taxa de Filtração Glomerular/efeitos dos fármacos , Glomérulos Renais/efeitos dos fármacos , Permeabilidade/efeitos dos fármacos , Animais , Glicemia/metabolismo , Diabetes Mellitus Experimental/metabolismo , Nefropatias Diabéticas/tratamento farmacológico , Nefropatias Diabéticas/metabolismo , Ficoll/metabolismo , Glomérulos Renais/metabolismo , Masculino , Ratos Wistar
7.
Ultrastruct Pathol ; 42(2): 155-161, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29419350

RESUMO

Excessive consumption of carbohydrate and fat increases the risk of liver disease. We hypothesized that swim exercise can protect hepatocytes from ultra-structural damage induced by high cholesterol and fructose diets (HCFD). Rats were either fed with HCFD (model group) or a standard laboratory chow (control group) for 15 weeks before being sacrificed. Swim exercise trained rats started the treatment from the 11th week until the sacrifice day, end of week 15. Blood samples were assayed for biomarkers of liver injury and adiponectin. The harvested liver tissues were examined using transmission electron microscopy (TEM). TEM images revealed substantial damage and accumulation of lipid droplets (steatosis) in the hepatocytes of the model group that was inhibited by swim exercise. In addition, HCFD significantly (p < 0.0005) increased insulin resistance index (HOMA-IR), interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-α), alanine aminotransferase (ALT), and aspartate aminotransferase (AST), which were effectively (p < 0.02) decreased by a swim exercise to levels comparable to control group. Whereas, swim exercise increased adiponectin levels in HCFD group (p < 0.03). These results show that HCFD-induced hepatic injury is ameliorated by swim training exercise possibly via restoration of a normal blood sugar and lipid, induction of adiponectin and inhibition of inflammatory, and liver injury biomarkers.


Assuntos
Dieta Hiperlipídica/efeitos adversos , Frutose/toxicidade , Hepatócitos/ultraestrutura , Hepatopatia Gordurosa não Alcoólica , Condicionamento Físico Animal/fisiologia , Animais , Glicemia , Frutose/administração & dosagem , Hepatócitos/patologia , Resistência à Insulina , Microscopia Eletrônica de Transmissão , Hepatopatia Gordurosa não Alcoólica/etiologia , Hepatopatia Gordurosa não Alcoólica/fisiopatologia , Hepatopatia Gordurosa não Alcoólica/prevenção & controle , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley , Natação
8.
Fetal Pediatr Pathol ; 37(2): 102-108, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29494779

RESUMO

BACKGROUND: Metachromatic leukodystrophy (MLD) is an autosomal recessive lysosomal storage disease, caused by a deficiency of arylsulfatase A, and leads to demyelination of the nervous system. A putative association between MLD and gallbladder pathology including malignancy is documented in the medical literature. CASE REPORT: A 10-year-old boy with MLD was found to have a papillary growth within a cystically dilated gallbladder. The lesion was confirmed to be papillomatosis/polyp with focal intestinal metaplasia. Dysplasia was not identified. CONCLUSION: MLD may be associated with a spectrum of gallbladder pathology including neoplastic conditions. Pathologists and clinicians should be aware of this association/risk. The patient may be offered regular ultrasound screening of the gallbladder.


Assuntos
Doenças da Vesícula Biliar/etiologia , Leucodistrofia Metacromática/complicações , Pólipos/etiologia , Criança , Humanos , Masculino
9.
Cancer Cell Int ; 14(1): 90, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25298748

RESUMO

BACKGROUND: Up-regulation of the PI3K/mTOR (phosphatidylinositol-3' kinase/mammalian target of rapamycin) signaling is common in carcinoma. Consistently, targeting these molecules has been shown to halt the growth of many tumors. The main purpose of this study was to develop surrogate biomarkers of the antitumor activity of PI3K/mTOR inhibitors. METHODS: Fragments from eight tumors were collected immediately after resection in ice-cold RPMI gassed with 95% O2 :5% CO2. Viability was determined by measuring tumor cellular respiration (mitochondrial O2 consumption). The specimens were incubated at 37°C with and without 50 nM GSK2126458 (a highly potent and selective inhibitor of PI3K/mTOR) for 90 min. The tissue was then processed for histology, measurement of intracellular caspase-3 activity (using the caspase-3 substrate N-acetyl-asp-glu-val-asp-7-amino-4-methylcoumarin), and immunohistochemical detection of the apoptotic biomarkers caspase-3, cytochrome C, and annexin A2. RESULTS: GSK2126458 induced morphologic changes in four tumors (two invasive ductal carcinomas, one invasive lobular carcinoma, and one ovarian dysgerminoma), intracellular caspase-3 activity in three tumors (two invasive ductal carcinomas and one poorly differentiated signet ring adenocarcinoma of gastric origin), and immunohistochemical evidence of apoptosis in at least four tumors (three invasive ductal carcinomas and one adenocarcinoma of gastric origin). Two tumors (ovarian serous carcinoma and moderately differentiated adenocarcinoma of colorectal origin) demonstrated no treatment effect. CONCLUSION: These preliminary results demonstrate the feasibility of using in vitro biomarkers for detecting antitumor activities of the rapidly emerging PI3K/mTOR inhibitors.

10.
Acta Cytol ; 58(2): 198-210, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24525845

RESUMO

BACKGROUND: Epithelioid trophoblastic tumor (ETT) is a rare gestational trophoblastic neoplasm of intermediate trophoblasts. It was first described by Shih and Kurman [Am J Surg Pathol 1998;22:1393-1403] who outlined its clinicopathologic characteristics in 14 cases, establishing it as a distinct entity of gestational trophoblastic tumors. It represents 1.39% of all gestational trophoblastic diseases. Most cases are reported in reproductive-age women following a prior gestation with a time interval between 2 weeks and 30 years. ETT is extremely rare in postmenopausal women. It is commonly misdiagnosed as a squamous cell carcinoma (SCC), poorly differentiated carcinoma or another gestational trophoblastic tumor. Limited data is available regarding its cytological features on Pap smears. CASES: We report 2 cases of uterine ETT occurring in postmenopausal women. In both cases, an initial diagnosis of an SCC and a poorly differentiated carcinoma was rendered. We highlight the features of ETT helpful in differentiating it from other mimickers with emphasis on rarely reported cytological features of this neoplasm. CONCLUSION: ETT is a rare tumor with characteristic cytological features, but is commonly confused with SCC. A high index of suspicion is needed to make the correct diagnosis or to raise the consideration of ETT, especially in cases with an increased ß-human chorionic gonadotropin.


Assuntos
Células Epitelioides/patologia , Neoplasias Trofoblásticas/diagnóstico , Neoplasias Trofoblásticas/patologia , Carcinoma de Células Escamosas/diagnóstico , Carcinoma de Células Escamosas/patologia , Erros de Diagnóstico , Feminino , Humanos , Pessoa de Meia-Idade , Pós-Menopausa
11.
Cureus ; 16(2): e53419, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38314378

RESUMO

Metaplastic breast cancer (MpBC) is a rare form of breast cancer known for suboptimal response to chemotherapy, high recurrence rate, poor prognosis, and limited treatment options. Recent studies have reported that MpBC has high expression of programmed death ligand 1 and tumor-infiltrating lymphocytes, indicating the potential effectiveness of immunotherapy (IO) in MpBC. In addition, several reports have demonstrated the activity of IO in MpBC. In this case report, we present a case of recurrent MpBC that achieved durable, rapid, complete remission with atezolizumab (anti-PD-L1) and nab-paclitaxel with a continued response even after discontinued therapy.

12.
J Educ Health Promot ; 13: 36, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38545308

RESUMO

BACKGROUND: Enrolling in medical school launches a more demanding and stressful way of life for newly admitted students. Some students will struggle academically and will ultimately drop out from medical school. The study aims to understand the perspectives that dropped-out students have and their opinion regarding possible preventative solutions. MATERIALS AND METHODS: This study uses a mixed-method approach. The results of students' examinations in the first 2 years of admission (within four academic years from 2016 until 2020) were collected from the medical school records. A questionnaire was developed to investigate the causes of early attrition during the study period. All dropped-out students who were admitted were included in this study. RESULTS: The study included 479 admitted students, 349 (72.9%) were females; 152 (31.7%) students dropped out in the premedical program (first two years); 104 (68.4%) of the dropped-out students were females. Thirty-five (23%) students responded to the questionnaire. Twenty-eight (80%) respondents believed that their low academic performance and leaving medical school was primarily related to psychological problems, 19 (54%) of respondents reported leaving for social reasons, and lack of self-organization in 13 (37.1%) respondents. Human anatomy was recorded as the most difficult course in the first year by 21 (63.6%) students. CONCLUSIONS: The cause of attrition is often multifactorial and complex. Psychological problems are one of the important factors in students with low academic performance and dropping out of the students. Some difficult courses in the curriculum may affect the students' academic performance leading to their attrition.

13.
J Taibah Univ Med Sci ; 19(2): 447-452, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38455852

RESUMO

Objectives: Placement in medical schools is highly sought after worldwide with fierce competition among applicants. However, some of the best students withdraw after being accepted to medical school. The aim of this study was to investigate early student attrition within the first 2 years of medical school and determine its relationship to admission selection tools. Methods: Quantitative research was conducted at the College of Medicine and Health Sciences from 2016 until 2020, during which time routine admission data and students' examination results for the first 2 years were collected and analyzed. Results: The attrition rate during the study period was 31.7%. High school and college written examination scores were significantly related to completing the premedical program (p = 0.001 and p = 0.002, respectively). Female students scored significantly higher in multiple mini interviews (MMIs) compared with male counterparts (p < 0.001). However, the difference in MMI score was not related to student attrition (p = 0.148). Conclusion: The cause of early attrition is complex and cannot be attributed to a single factor.Undergraduate high school score and written admission examination results were statistically significant factors in relation to student attrition rate and low academic performance. The results of this study showed that the female students scored significantly higher in the multiple MMI tests compared to male students. However, MMI score alone was not significantly related to student attrition.

14.
Mod Pathol ; 26(6): 799-805, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23328976

RESUMO

Recent breakthrough findings revealed that most patients with idiopathic (primary) membranous glomerulonephritis have IgG4 antibodies to the phospholipase A2 receptor (PLA2R). These IgG4 antibodies can be detected in the glomerular immune complexes and they colocalize with PLA2R. In secondary forms of membranous glomerulonephritis, such IgG4 antibodies are absent or less prevalent. There are no studies addressing the IgG subclass distribution across different stages of membranous glomerulonephritis. During a 25-month period, we identified 157 consecutive biopsies with membranous glomerulonephritis with adequate tissue for light, immunofluorescence and electron microscopy. Of the 157 membranous glomerulonephritis cases, 114 were primary membranous glomerulonephritis and 43 were secondary membranous glomerulonephritis. We compared the intensity of IgG subclass staining (on a semiquantitative scale of 0 to 3+) and the IgG subclass dominance between primary and secondary membranous glomerulonephritis and between the different stages of membranous glomerulonephritis. In primary membranous glomerulonephritis most (76% of cases) were IgG4 dominant. In contrast, in secondary membranous glomerulonephritis IgG1 was dominant in 60% of biopsies (P=0.0018). Interestingly, in early stage (stage 1) primary membranous glomerulonephritis, IgG1 was the dominant IgG subclass (64% of cases); in all later stages IgG4 dominated (P=0.0493). It appears that there is an inverse relationship between the intensity of glomerular capillary IgG4 and C1q staining. In secondary forms of membranous glomerulonephritis (heterogeneous group with low case numbers), we did not find such associations. Our data indicate that in early stage membranous glomerulonephritis, antibody response is different from later stages, with IgG1 dominant deposits. It is possible that early on, antigens other than PLA2R have an important role, Alternately, there may be an IgG subclass switch in the antibody response with IgG4 taking over later as the dominant immunoglobulin.


Assuntos
Glomerulonefrite Membranosa/imunologia , Imunoglobulina G/análise , Glomérulos Renais/imunologia , Biomarcadores/análise , Biópsia , Complemento C1q/análise , Progressão da Doença , Imunofluorescência , Glomerulonefrite Membranosa/patologia , Humanos , Imunoglobulina G/classificação , Glomérulos Renais/ultraestrutura , Microscopia Eletrônica , Receptores da Fosfolipase A2/imunologia
15.
Virol J ; 10: 22, 2013 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-23320837

RESUMO

BACKGROUND: Cellular bioenergetics (cellular respiration and accompanying ATP synthesis) is a highly sensitive biomarker of tissue injury and may be altered following infection. The status of cellular mitochondrial O(2) consumption of the lung in pulmonary RSV infection is unknown. METHODS: In this study, lung fragments from RSV-infected BALB/c mice were evaluated for cellular O(2) consumption, ATP content and caspase activity. The disease was induced by intranasal inoculation with the RSV strain A2 and lung specimens were analyzed on days 2-15 after inoculation. A phosphorescence O(2) analyzer that measured dissolved O(2) concentration as a function of time was used to monitor respiration. The caspase-3 substrate analogue N-acetyl-asp-glu-val-asp-7-amino-4-methylcoumarin (Ac-DEVD-AMC) was used to monitor intracellular caspases. RESULTS: O(2) concentration declined linearly with time when measured in a sealed vial containing lung fragment and glucose as a respiratory substrate, revealing its zero-order kinetics. O(2) consumption was inhibited by cyanide, confirming the oxidation occurred in the respiratory chain. Cellular respiration increased by 1.6-fold (p<0.010) and ATP content increased by 3-fold in the first week of RSV infection. Both parameters returned to levels found in uninfected lungs in the second week of RSV infection. Intracellular caspase activity in infected lungs was similar to uninfected lungs throughout the course of disease. CONCLUSIONS: Lung tissue bioenergetics is transiently enhanced in RSV infection. This energy burst, triggered by the virus or virus-induced inflammation, is an early biomarker of the disease and may be targeted for therapy.


Assuntos
Metabolismo Energético , Pulmão/metabolismo , Infecções por Vírus Respiratório Sincicial/metabolismo , Vírus Sinciciais Respiratórios/fisiologia , Trifosfato de Adenosina/metabolismo , Animais , Caspase 3/metabolismo , Feminino , Humanos , Pulmão/enzimologia , Pulmão/patologia , Pulmão/virologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Oxigênio/metabolismo , Infecções por Vírus Respiratório Sincicial/patologia , Infecções por Vírus Respiratório Sincicial/virologia
16.
Cureus ; 15(2): e34912, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36938175

RESUMO

Introduction Head and neck squamous cell carcinoma (HNSCC) is the sixth most common cancer worldwide. The prevalence of human papillomavirus (HPV) in HNSCC varies across regions. Objective This study aimed to determine the prevalence of high-risk HPV (hrHPV) among patients with HNSCC in the Middle East region. Methods Samples from patients with oropharyngeal or laryngeal lesions who underwent biopsy or resection at a tertiary care hospital from 2010 to 2015 were collected. Those confirmed as squamous cell carcinoma (SCC) on histopathology were identified as cases (n = 61), whereas benign lesions were used as controls (n = 83). Immunohistochemistry (IHC) for p16, p53, Ki-67, and in situ hybridization (ISH) for hrHPV genotypes 16, 18, 31, 33, 35, 39, 45, 51, 52, 56, 58, and 66 were performed on all cases. Results A total of 154 cases were studied: 61 squamous cell cancers (cases), 83 benign lesions (control), and 10 dysplasia specimens. Among the cases, only five (8.6%) were positive for hrHPV, whereas only one control specimen tested positive. The SCC group had higher mean age, male sex, and history of cigarette smoking and alcohol usage. Among the hrHPV-positive SCC cases, 80% had a tumor in the oropharyngeal region. All hrHPV-positive cases were positive for p16 and p53 immunostains. Conclusion Among HNSCC cases, hrHPV was detected at a lower rate compared to other regions of the world. This study suggests that hrHPV plays a minor role in the pathogenesis of HNSCC in this region, compared to tobacco use and alcohol consumption.

17.
Biomedicines ; 11(2)2023 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-36830898

RESUMO

Lower extremity arterial disease (LEAD) is a major risk factor for amputation in diabetic patients. The advanced glycation end products (AGEs)/endothelin-1 (ET-1)/nitric oxide synthase (NOS) axis-mediated femoral artery injury with and without metformin has not been previously investigated. Type 2 diabetes mellitus (T2DM) was established in rats, with another group of rats treated for two weeks with 200 mg/kg metformin, before being induced with T2DM. The latter cohort were continued on metformin until they were sacrificed at week 12. Femoral artery injury was established in the diabetic group as demonstrated by substantial alterations to the femoral artery ultrastructure, which importantly were ameliorated by metformin. In addition, diabetes caused a significant (p < 0.0001) upregulation of vascular tissue levels of AGEs, ET-1, and iNOS, as well as high blood levels of glycated haemoglobin, TNF-α, and dyslipidemia. All of these parameters were also significantly inhibited by metformin. Moreover, metformin treatment augmented arterial eNOS expression which had been inhibited by diabetes progression. Furthermore, a significant correlation was observed between femoral artery endothelial tissue damage and glycemia, AGEs, ET-1, TNF-α, and dyslipidemia. Thus, in a rat model of T2DM-induced LEAD, an association between femoral artery tissue damage and the AGEs/ET-1/inflammation/NOS/dyslipidemia axis was demonstrated, with metformin treatment demonstrating beneficial vascular protective effects.

18.
Am J Transl Res ; 14(7): 4678-4687, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35958488

RESUMO

Several in vitro and in vivo studies have shown that the mammalian target of rapamycin (mTOR) inhibitor sirolimus (rapamycin) suppresses thymus cellular respiration. The objective of this study is to investigate the chronic dose-dependent effects of sirolimus in the thymus. This was monitored using body weight, histomorphology, caspase-3 expression, cytochrome C immunohistochemistry, and cellular bioenergetics as surrogate biomarkers. BALB/c mice received intraperitoneal injections of either sirolimus (2.5, 5, or 10 µg/g) or dimethyl sulfoxide (0.1 µL/g) as a control for 4 weeks. At the end of the treatment, fragments were collected from the thymus, small intestine, adrenal gland, and kidney. They were processed for assessing histologic changes, measuring cellular respiration and ATP levels. Immunohistochemical stain of caspase-3 and cytochrome C was performed on paraffin-embedded tissue. The treated animals exhibited a dose-dependent reduction in weight gain despite adequate food intake. Sirolimus produced significant thymic derangements, manifested by dose-dependent tissue involution, increased cortical apoptotic bodies, increased caspase-3-positive lymphocytes, and increased rate of cellular respiration without a concomitant increase in cellular ATP. There were no similar changes in cellular ATP in the other assessed organs. The effects on thymic cellular bioenergetics suggest mitochondrial derangements, uncoupling of oxidative phosphorylation, and induction of apoptosis.

19.
Nutrients ; 14(21)2022 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-36364909

RESUMO

The present study investigated the effects of α-bisabolol on DOX-induced testicular damage in rats. Testicular damage was induced in rats by injecting DOX (12.5 mg/kg, i.p., single dose) into rats. α-Bisabolol (25 mg/kg, i.p.) was administered to the rats along with DOX pre- and co-treatment daily for a period of 5 days. DOX-injected rats showed a decrease in absolute testicular weight and relative testicular weight ratio along with concomitant changes in the levels/expression levels of oxidative stress markers and Nrf2 expression levels in the testis. DOX injection also triggered the activation of NF-κB/MAPK signaling and increased levels/expression levels of pro-inflammatory cytokines (TNF-α, IL-6, and IL-1ß) and inflammatory mediators (iNOS and COX-2) in the testis. DOX triggered apoptosis, manifested by an increment in the expression levels of pro-apoptotic markers (Bax, Bcl2, cleaved caspase-3 and -9, and cytochrome-C) and a decline in the expression levels of anti-apoptotic markers (Bcl-xL and Bcl2) in the testis. Additionally, light microscopy revealed the changes in testicular architecture. α-Bisabolol rescued alterations in the testicular weight; restored all biochemical markers; modulated the expression levels of Nrf2-mediated antioxidant responses, NF-κB/MAPK signaling, endoplasmic reticulum (ER) stress, and apoptosis markers in DOX-injected testicular toxicity in rats. Based on our findings, it can be concluded that α-bisabolol has the potential to attenuate DOX-induced testicular injury by modifying NF-κB/MAPK signaling and the ER-stress-mediated mitochondrial pathway of apoptosis by invoking Nrf2-dependent antioxidant defense systems in rats. Based on the findings of the present study, α-bisabolol could be suggested for use as an agent or adjuvant with chemotherapeutic drugs to attenuate their deleterious effects of DOX on many organs including the testis. However, further regulatory toxicology and preclinical studies are necessary before making recommendations in clinical tests.


Assuntos
Antioxidantes , NF-kappa B , Animais , Masculino , Ratos , Antioxidantes/farmacologia , Antioxidantes/metabolismo , Apoptose , Doxorrubicina/toxicidade , Fator 2 Relacionado a NF-E2/metabolismo , NF-kappa B/metabolismo , Estresse Oxidativo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Testículo , Sistema de Sinalização das MAP Quinases , Estresse do Retículo Endoplasmático
20.
Am J Kidney Dis ; 58(2): 276-81, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21705124

RESUMO

Proliferative glomerulonephritis with monoclonal immunoglobulin G (IgG) deposits (PGNMIGD) is a recently recognized glomerular disease. Light microscopy usually resembles membranoproliferative glomerulonephritis. Glomerular deposits are mostly IgG3 κ; however, unlike in the usual forms of monoclonal immunoglobulin deposition disease, extraglomerular deposits are absent. If PGNMIGD is secondary to the glomerular deposition of circulating monoclonal IgG, it is expected to recur in kidney allografts with the same pattern of monoclonal IgG deposition. We reviewed our kidney biopsy files between January 1, 2003, and January 4, 2010, and identified 21 biopsy specimens with PGNMIGD, mostly with glomerular IgG3 κ deposits. Of the 21 biopsy specimens, 4 were from kidney allografts; 2 were recurrent and the other 2 were de novo diseases. Recurrent PGNMIGD develops rapidly, causing proteinuria. This rapid recurrence of PGNMIGD in kidney allografts provides further proof that PGNMIGD is secondary to the glomerular deposition of circulating monoclonal IgG.


Assuntos
Glomerulonefrite Membranoproliferativa/imunologia , Imunoglobulina G , Transplante de Rim , Complicações Pós-Operatórias/imunologia , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva , Adulto Jovem
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