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1.
Metab Brain Dis ; 2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38900359

RESUMO

Silicon dioxide nanoparticles (SiO2-NPs) can be found in many products, such as composites, paints, ceramics, consumer products, and food additives. We recently demonstrated that via breastfeeding, SiO2-NPs transfer to the offspring's brain, interfering negatively with hippocampus development. In this work, we evaluated the protective effect of grape seed extract (GSE) against the adverse effects of SiO2-NPs. After delivery, animals were administered 25 mg/kg SiO2-NPs with/without GSE (300 mg/kg) for 20 days (from 2nd to 21st days post-delivery) by gavage. SiO2-NPs increased malondialdehyde concentration and decreased antioxidant activity in the offspring's hippocampi. The mean number of dark neurons (DNs) was significantly higher in the hippocampi of the SiO2-NPs group, whereas the mean number of DCX + cells was significantly lower than in the control group. The offspring in the SiO2-NPs groups had a weak cognitive performance in adulthood. Interestingly, these adverse effects of SiO2-NPs were alleviated in the GSE-treated groups. Therefore, GSE can attenuate the damaging effects of maternal exposure to SiO2-NPs during lactation.

2.
Biol Trace Elem Res ; 202(5): 1991-1997, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-37721681

RESUMO

Male infertility is a global public health issue, but studies on the correlation between the dietary components and sperm quality showed inconclusive results due to the heterogeneous population with different dietary habits and environmental stimuli. Herein, the correlation of dietary macro- and micro-mineral intake was evaluated with quality/quantity and oxidant/antioxidant status of seminal fluid in infertile compared to the healthy men. One hundred twenty men attending to the infertility clinic of Ayatollah Mousavi Hospital in Zanjan City were enrolled. Seminal fluid was extracted, and groups were categorized into the infertile (non-standard) and normal (standard) groups based on the WHO, 2020 criteria. Food frequency questionnaire was completed. Seminal malondialdehyde (MDA) and total antioxidant capacity (TAC) were measured by ELISA kit based on the manufacture's instruction. An independent sample t-test was used to determine differences between the two groups, and linear regression model was used to determine the effect of each dietary macro/micro mineral intake on these parameters. Adjusting for all parameters, dietary selenium increased 3.7-folds the seminal TAC level (p=0.04) and decreased sperm with non-progressive motility by 2.4-folds (p=0.04). Higher manganese intake increased the sperm count by 7.8-folds (p=0.005). Dietary copper decreased sperm vitality and increased sperm with slow motility (OR= -1.7, 95% CI= -59.8, -9.9; p=0.007). Dietary zinc (OR=1.24, p=0.01) and iron (OR=1.5, p=0.02) showed a positive effect on sperm vitality. None of macro and micro minerals showed a significant effect on the seminal MDA level. Daily intake of adequate amounts of micro and macro minerals improves sperm quality and increases the antioxidant capacity of the seminal fluid; however, copper showed a negative correlation that must be evaluated in future studies.


Assuntos
Infertilidade Masculina , Sêmen , Humanos , Masculino , Antioxidantes , Oxidantes , Estudos de Casos e Controles , Cobre , Motilidade dos Espermatozoides , Espermatozoides , Minerais , Contagem de Espermatozoides
4.
Commun Biol ; 6(1): 674, 2023 06 27.
Artigo em Inglês | MEDLINE | ID: mdl-37369761

RESUMO

STED microscopy is widely used to image subcellular structures with super-resolution. Here, we report that restoring STED images with deep learning can mitigate photobleaching and photodamage by reducing the pixel dwell time by one or two orders of magnitude. Our method allows for efficient and robust restoration of noisy 2D and 3D STED images with multiple targets and facilitates long-term imaging of mitochondrial dynamics.


Assuntos
Aprendizado Profundo , Microscopia de Fluorescência/métodos , Imageamento Tridimensional
5.
bioRxiv ; 2023 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-36747618

RESUMO

STED microscopy is widely used to image subcellular structures with super-resolution. Here, we report that denoising STED images with deep learning can mitigate photobleaching and photodamage by reducing the pixel dwell time by one or two orders of magnitude. Our method allows for efficient and robust restoration of noisy 2D and 3D STED images with multiple targets and facilitates long-term imaging of mitochondrial dynamics.

6.
Int J Fertil Steril ; 17(1): 22-27, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36617198

RESUMO

BACKGROUND: Insulin is an essential factor that controls female reproductive system. Insulin signaling via Foxo1 and Akt1 can improve steroidogenesis, cell proliferation, and protein synthesis. We aimed to determine the effect of insulin on possible changes in gene expression, hormonal status, and histological aspects of the ovary following the induction of the animal model of polycystic ovary syndrome (PCOS). MATERIALS AND METHODS: In this experimental study, 24 adult female NMRI mice weighing 25-30 g were randomly placed in three groups: control, PCOS (60 mg/kg dehydroepiandrosterone (DHEA) for 20 days, and PCOS+insulin (60 mg/kg DHEA for 20 days+100 µL insulin diluted in water twice a week for 30 consecutive days). Blood specimens were obtained from the heart and the serum levels of testosterone, progesterone, and estradiol were measured. Right, and left ovaries were removed for real-time polymerase chain reaction (PCR) and stereological study. RESULTS: DHEA injection significantly amplified the concentration of testosterone, progesterone, and estradiol. While insulin treatment amended the level of reproductive hormones. DHEA injection significantly reduced the expression levels of Irs1-4, Pdk1, Pi3k, and Akt1-3 and raised the expression level of Caspase-3. However, insulin administration amplified expression levels of Irs1-4, Pdk1, Pi3k, and Akt1-3, and reduced Caspase-3. The total volume of ovarian tissue in mice receiving DHEA significantly declined compared to the control group. Besides, a substantial decrease was detected in the number of ovarian antral, Graafian, and primordial follicles and also in the total number of corpus luteum following DHEA administration. Comparison of structural alterations in ovarian tissue between the PCOS+insulin and the PCOS groups displayed that insulin administration improved the total number of Graafian, primordial, and antral follicles and also corpus luteum. CONCLUSION: In general, short-term insulin treatment showed improvement in hormonal balance, folliculogenesis, and insulin resistance in the ovaries of the PCOS mice model.

7.
Mol Neurobiol ; 60(4): 2062-2069, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36596965

RESUMO

Stroke is a leading cause of death and disability worldwide. It is among the most common neurological disorders with an 8-10% lifetime risk. Ischemic stroke accounts for about 85% of all strokes and damages the brain tissue via various damaging mechanisms. Following cerebral ischemia, the disrupted blood-brain barrier (BBB) leads to cerebral edema formation caused by activation of oxidative stress, inflammation, and apoptosis, targeting primarily endothelial cells. Activation of the protective mechanisms might favor fewer damages to the neural tissue. MicroRNA (miR)-126 is an endothelial cell-specific miR involved in angiogenesis. MiR-126 orchestrates endothelial progenitor cell functions under hypoxic conditions and could inhibit ischemia-induced oxidative stress and inflammation. It alleviates the BBB disruption by preventing an augment in matrix metalloproteinase level and halting the decrease in the junctional proteins, including zonula occludens-1 (ZO-1), claudin-5, and occludin levels. Moreover, miR-126 enhances post-stroke angiogenesis and neurogenesis. This work provides a therapeutic perspective for miR-126 as a new approach to treating cerebral ischemia.


Assuntos
Isquemia Encefálica , MicroRNAs , Acidente Vascular Cerebral , Humanos , Células Endoteliais/metabolismo , Isquemia Encefálica/metabolismo , Acidente Vascular Cerebral/metabolismo , Infarto Cerebral/metabolismo , Barreira Hematoencefálica/metabolismo , MicroRNAs/genética , Infarto da Artéria Cerebral Média/metabolismo
8.
Rev Int Androl ; 21(2): 100327, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36396581

RESUMO

INTRODUCTION AND OBJECTIVES: Aging is an irreversible process associated with decreased biological functions that can lead to the reduction of reproductive organs capacities in males and females. Paternal age is a significant predictor of offspring health and development. So, the aim of this study was to evaluate the effects of vitamin C on histopathological and biochemical testicular changes following aging process with a focus on stereological methods. MATERIAL AND METHODS: For this study, 48 adult male NMRI mice were divided into two control and experimental groups. Mice in experimental group were supplemented with vitamin C (150mg/kg) including 24-h interval by oral gavage for 33 weeks. Same regime was performed for animals in control group except that vitamin C was replaced by water. Then, right testes were extracted for stereological and left testes were used for molecular analyses on weeks 8, 12, and 33. RESULTS: Our findings showed low semen quality, decreased level of serum Luteinizing hormone (LH), Follicle-stimulating hormone (FSH), and testosterone along with increased reactive oxygen species (ROS) production and higher apoptotic gene expression following aging. Stereological studies showed that the volume of testes, the length of seminiferous tubules, and the number of spermatogenic and none-spermatogenic cells decreased significantly during aging. Also, vitamin C consumption for 33 weeks significantly improved biochemical and histological indices. The impact of aging on male reproduction seems to be inevitable worldwide. Therefore, the use of protective and preventive remedies conserving male fecundity is very important and based on our results, vitamin C is a beneficial candidate for improving age-related testicular changes due to aging process.


Assuntos
Ácido Ascórbico , Testículo , Feminino , Masculino , Camundongos , Animais , Ácido Ascórbico/farmacologia , Ácido Ascórbico/metabolismo , Análise do Sêmen , Túbulos Seminíferos/patologia , Testosterona
9.
Allergol Immunopathol (Madr) ; 50(6): 137-146, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36335457

RESUMO

Recent studies have shown that polycystic ovary syndrome (PCOS) affects about 6% of women worldwide. It is associated with reproductive and metabolic dysfunction. Caffeine is naturally found in tea, cocoa, and coffee. It has been shown that caffeine can change hormonal profiles, stimulate ovulation, and enhance fertility. Therefore, in this study, the effects of caffeine on rats with PCOS were investigated. For this purpose, 40 female rats were divided into five groups: (1) control group (without any intervention), (2) sham group (administration of olive oil as a caffeine solvent), (3) PCOS group (injection of 2 mg of estradiol valerate for each rat), (4) caffeine group (administration of 37.5 mg/kg caffeine for each rat), and (5) PCOS + caffeine group. After 21 days of treatment, the ovaries of rats were removed and prepared for further evaluations, including hematoxylin and eosin staining, TUNEL assay, real-time PCR, and biochemical analysis. Administration of caffeine in PCOS mice considerably reduced both the volume of the ovary (P < 0.05) and follicular clusters (P < 0.01). However, superoxide dismutase and glutathione peroxidase were dramatically active in the PCOS + caffeine group compared to others (P < 0.05). Besides, caffeine treatment in PCOS mice led to Bax reduction and increased Bcl-2 expression. On the other hand, the expression of IL-6 and TNF-α in PCOS + caffeine group was high compared to other groups. We found that caffeine can reduce apoptosis and inflammation in PCOS ovaries and enhance the unpleasant symptoms of PCOS.


Assuntos
Síndrome do Ovário Policístico , Humanos , Ratos , Feminino , Camundongos , Animais , Síndrome do Ovário Policístico/tratamento farmacológico , Síndrome do Ovário Policístico/metabolismo , Antioxidantes/farmacologia , Antioxidantes/uso terapêutico , Antioxidantes/metabolismo , Cafeína/uso terapêutico , Citocinas , Ratos Wistar , Modelos Animais de Doenças
10.
Clin Lab ; 68(7)2022 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-35975541

RESUMO

BACKGROUND: Understanding the determinants of long-term overall survival (OS) of thalassemia patients (TPs) is the mainstay of care. METHODS: As a retrospective survey, we assessed the data of 769 TPs who had regular follow-up and blood transfusion for at least 30 years from 1990 - 2019. We utilized semi-parametric proportional hazards mixture cure-rate regression to discover the factors with a significant effect on short- and long-term OS separately. RESULTS: The 25- and 30-year OS for the TPs were calculated to be 98.7% and 90.4%, respectively. Each five-year age escalation was associated with a 30% decrease in the probability of being short-term survivors (HR = 1.06, p = 0.047). Parental family relationship influenced both cured (OR = 3.00, p = 0.017) and uncured (HR = 0.50, p = 0.046) TPs. Moreover, the type of iron chelation drug, liver iron concentration, and normal EF results had a significant effect on long-term OS. Aging, parental consanguinity, liver and cardiac siderosis, higher ferritin levels, and low hemoglobin level were associated with poorer prognosis in TPs. CONCLUSIONS: However, deferoxamine followed by multiple drugs as iron chelation, severe liver siderosis, and abnormal EF declined the probability of long-term OS among TPs. This can be considered by health policy decision-makers to enforce the screening program more strictly.


Assuntos
Sobrecarga de Ferro , Siderose , Talassemia , Talassemia beta , Humanos , Ferro , Quelantes de Ferro , Prognóstico , Estudos Retrospectivos , Siderose/complicações , Talassemia/terapia , Talassemia beta/complicações , Talassemia beta/terapia
11.
Apoptosis ; 27(11-12): 852-868, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-35876935

RESUMO

Recent investigations of COVID-19 have largely focused on the effects of this novel virus on the vital organs in order to efficiently assist individuals who have recovered from the disease. In the present study we used hippocampal tissue samples extracted from people who died after COVID-19. Utilizing histological techniques to analyze glial and neuronal cells we illuminated a massive degeneration of neuronal cells and changes in glial cells morphology in hippocampal samples. The results showed that in hippocampus of the studied brains there were morphological changes in pyramidal cells, an increase in apoptosis, a drop in neurogenesis, and change in spatial distribution of neurons in the pyramidal and granular layer. It was also demonstrated that COVID-19 alter the morphological characteristics and distribution of astrocyte and microglia cells. While the exact mechanism(s) by which the virus causes neuronal loss and morphology in the central nervous system (CNS) remains to be determined, it is necessary to monitor the effect of SARS-CoV-2 infection on CNS compartments like the hippocampus in future investigations. As a result of what happened in the hippocampus secondary to COVID-19, memory impairment may be a long-term neurological complication which can be a predisposing factor for neurodegenerative disorders through neuroinflammation and oxidative stress mechanisms.


Assuntos
COVID-19 , Humanos , Apoptose , SARS-CoV-2 , Neurogênese/fisiologia , Hipocampo , Causalidade
12.
J Chem Neuroanat ; 123: 102116, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35660069

RESUMO

Tramadol, an opioid used as analgesic, can induce neurotoxic effects associated to cognitive dysfunction. Moreover, caffeine has been reported to have neuroprotective effects. In this regard, we hypothesized that administration of caffeine can modulate tramadol-induced damages in cerebellum. For this study, forty male Wistar rats were divided into four groups: the control group, the tramadol group (50 mg/kg), the caffeine group (37.5 mg/kg), and the tramadol+caffeine group (50 mg/kg tramadol+37.5 mg/kg caffeine). At the end of study (day 21), after performing rotarod behavioral test, cerebellum tissue samples were removed and prepared for further evaluations including biochemical profile markers (MDA, GPx, and SOD), immunohistochemistry for Caspase-3, as well as the expression of genes involved in cellular processes such as inflammation markers (IL-1ß, HMGB1, IL-6, and TNF), apoptosis markers (Caspase-3, Caspase-8, Bax, and P21), and autophagy markers (LAMP2, ATG5, BECN1, and ATG12). Stereological evaluations were performed to determine the total volume of granular and molecular layers and white matter of cerebellum tissue and numerical density of the Purkinje cells. Our results showed that the stereological parameters, biochemical profiles (except MDA) and behavioral function were significantly higher in the tramadol+caffeine group compared to the tramadol group. Autophagy-related genes were significantly upregulated in tramadol+caffeine group compared to the tramadol group. While the expression of inflammatory and apoptosis genes, MDA level, as well as density of apoptosis cells were significantly lower in the tramadol+caffeine group compared to the tramadol group. Briefly, it can be concluded that administration of caffeine has neuroprotective effects in cerebellar damages induced by tramadol.


Assuntos
Fármacos Neuroprotetores , Tramadol , Animais , Apoptose , Cafeína/farmacologia , Caspase 3/metabolismo , Cerebelo/metabolismo , Inflamação/induzido quimicamente , Inflamação/metabolismo , Masculino , Fármacos Neuroprotetores/farmacologia , Estresse Oxidativo , Ratos , Ratos Wistar , Tramadol/farmacologia
13.
Iran J Public Health ; 51(1): 178-187, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35223639

RESUMO

BACKGROUND: Patients who are identified to be at a higher risk of mortality from COVID-19 should receive better treatment and monitoring. This study aimed to propose a simple yet accurate risk assessment tool to help decision-making in the management of the COVID-19 pandemic. METHODS: From Jul to Nov 2020, 5454 patients from Fars Province, Iran, diagnosed with COVID-19 were enrolled. A multiple logistic regression model was trained on one dataset (training set: n=4183) and its prediction performance was assessed on another dataset (testing set: n=1271). This model was utilized to develop the COVID-19 risk-score in Fars (CRSF). RESULTS: Five final independent risk factors including gender (male: OR=1.37), age (60-80: OR=2.67 and >80: OR=3.91), SpO 2 (≤85%: OR=7.02), underlying diseases (yes: OR=1.25), and pulse rate (<60: OR=2.01 and >120: OR=1.60) were significantly associated with in-hospital mortality. The CRSF formula was obtained using the estimated regression coefficient values of the aforementioned factors. The point values for the risk factors varied from 2 to 19 and the total CRSF varied from 0 to 45. The ROC analysis showed that the CRSF values of ≥15 (high-risk patients) had a specificity of 73.5%, sensitivity of 76.5%, positive predictive value of 23.2%, and negative predictive value (NPV) of 96.8% for the prediction of death (AUC=0.824, P<0.0001). CONCLUSION: This simple CRSF system, which has a high NPV, can be useful for predicting the risk of mortality in COVID-19 patients. It can also be used as a disease severity indicator to determine triage level for hospitalization.

14.
J Chem Neuroanat ; 120: 102071, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35051594

RESUMO

Cell replacement therapy (CRT) is one of the most effective approaches used to alleviate symptoms of neurodegenerative syndromes such as cerebellar ataxia (CA). Human olfactory epithelium mesenchymal stem cells (OE-MSCs) have been recognized as a promising candidate for CRT, due to their distinctive features including immunomodulatory properties and ease of accessible compared to other types of MSCs. Hence, the main goal of our study was to explore the impacts of OE-MSCs transplantation on behavioral, structural, and histological deficiencies in a rat model of CA. After obtained an informed consent from volunteers, OE-MSCs were obtained from their nasal cavity. Then, OE-MSCs were characterized by the positive expression of CD73, CD90, and CD105 as MSCs as well as nestin and vimentin as primitive neuroectodermal stem cells markers. Then, the animals were randomized into three control, 3-acetylpyridine (3-AP) treated, and 3-AP + cell groups. In both experimental groups, the rats received intraperitoneal injection of 3-AP (75 mg/kg), followed by the implantation of OE-MSCs into the cerebellum of 3-AP + cell group. The impact of engrafted OE-MSCs on motor coordination and performance along with biochemical, immunohistochemical, and stereological changes in the cerebellum of the rat models of CA were investigated. According to our findings, the administration of 3-AP decreased the cerebellar GSH concentration. The injection of 3-AP also altered the morphological characteristics of the cerebellar Golgi cells. On the other hand, OE-MSCs transplantation improved motor coordination in CA. Besides, the implantation of OE-MSCs reduced caspase-3 expression and microglia proliferation in the cerebellum upon 3-AP administration. Finally, the transplant of OE-MSCs protected Purkinje cells against 3-AP toxicity. In sum, the present study revealed considerable advantages of OE-MSCs in managing CA animal model.


Assuntos
Ataxia Cerebelar , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais , Animais , Humanos , Ratos , Ataxia Cerebelar/terapia , Células-Tronco Mesenquimais/metabolismo , Mucosa Olfatória
15.
BMC Public Health ; 22(1): 10, 2022 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-34986818

RESUMO

BACKGROUND: Narrowing a large set of features to a smaller one can improve our understanding of the main risk factors for in-hospital mortality in patients with COVID-19. This study aimed to derive a parsimonious model for predicting overall survival (OS) among re-infected COVID-19 patients using machine-learning algorithms. METHODS: The retrospective data of 283 re-infected COVID-19 patients admitted to twenty-six medical centers (affiliated with Shiraz University of Medical Sciences) from 10 June to 26 December 2020 were reviewed and analyzed. An elastic-net regularized Cox proportional hazards (PH) regression and model approximation via backward elimination were utilized to optimize a predictive model of time to in-hospital death. The model was further reduced to its core features to maximize simplicity and generalizability. RESULTS: The empirical in-hospital mortality rate among the re-infected COVID-19 patients was 9.5%. In addition, the mortality rate among the intubated patients was 83.5%. Using the Kaplan-Meier approach, the OS (95% CI) rates for days 7, 14, and 21 were 87.5% (81.6-91.6%), 78.3% (65.0-87.0%), and 52.2% (20.3-76.7%), respectively. The elastic-net Cox PH regression retained 8 out of 35 candidate features of death. Transfer by Emergency Medical Services (EMS) (HR=3.90, 95% CI: 1.63-9.48), SpO2≤85% (HR=8.10, 95% CI: 2.97-22.00), increased serum creatinine (HR=1.85, 95% CI: 1.48-2.30), and increased white blood cells (WBC) count (HR=1.10, 95% CI: 1.03-1.15) were associated with higher in-hospital mortality rates in the re-infected COVID-19 patients. CONCLUSION: The results of the machine-learning analysis demonstrated that transfer by EMS, profound hypoxemia (SpO2≤85%), increased serum creatinine (more than 1.6 mg/dL), and increased WBC count (more than 8.5 (×109 cells/L)) reduced the OS of the re-infected COVID-19 patients. We recommend that future machine-learning studies should further investigate these relationships and the associated factors in these patients for a better prediction of OS.


Assuntos
COVID-19 , Algoritmos , Mortalidade Hospitalar , Humanos , Aprendizado de Máquina , Modelos de Riscos Proporcionais , Estudos Retrospectivos , Fatores de Risco , SARS-CoV-2
16.
Toxicol Ind Health ; 38(1): 41-52, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35075925

RESUMO

Silicon dioxide nanoparticles (SiO2-NPs) are among the most widely used nanoparticles because of their chemical-physical properties. Since most brain maturation occurs in the neonatal period in humans and many mammals, it is important to understand how NPs may affect this process. This study tested the hypothesis that SiO2-NPs from treated dams could affect the hippocampus of neonatal rats during lactation. Twenty-four pregnant rats, after delivery, were divided into three groups of control, SiO2-NPs (25 mg/kg) and SiO2-NPs (100 mg/kg). The rats were treated from 2nd to 21st days post-delivery by gavage and the effects of these NPs were evaluated in the offspring's hippocampi to reveal the effects of maternal exposure to SiO2-NPs during lactation on the offspring's hippocampi. The offspring in the SiO2-NPs groups had higher malondialdehyde concentration and lower antioxidant activity in the hippocampi than the non-treated control group. The mean number of doublecortin positive (DCX+) cells and synaptophysin expression in the hippocampi of the SiO2-NPs groups were significantly lower than the control group, whereas the mean number of dark neurons was significantly higher. Also, animals in the SiO2-NPs groups had a weak cognitive performance in adulthood. In conclusion, maternal exposure to SiO2-NPs via breastfeeding could affect offspring's hippocampal neurogenesis and synaptogenesis, leading to impaired cognitive performance.


Assuntos
Hipocampo/efeitos dos fármacos , Hipocampo/crescimento & desenvolvimento , Exposição Materna/efeitos adversos , Nanopartículas/toxicidade , Neurogênese/efeitos dos fármacos , Dióxido de Silício/toxicidade , Animais , Feminino , Lactação , Gravidez , Ratos
17.
Biotech Histochem ; 97(2): 107-117, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33843374

RESUMO

Busulfan (BSU) is a chemotherapeutic drug that can cause subfertility or sterility in males. We investigated the effects of adipose tissue-derived mesenchymal stem cells (AT-MSC) conditioned medium (CM) (AT-MSC-CM) on histopathological and molecular characteristics of mouse testes exposed to BSU using stereology. We used adult male mice divided randomly into five groups: control, Dulbecco's modified Eagle's medium (DMEM), dimethyl sulfoxide (DMSO), BSU, and BSU + CM. Thirty-five days following BSU injection, sperm and testis tissues were harvested for stereological and molecular studies. The BSU group exhibited significantly reduced testis volume, interstitium and tubules compared to the other groups, although the volume of the testis remained unchanged for BSU and CM groups. The number of testis cells was reduced in the BSU group compared to the other groups. The CM group exhibited a significantly increased number of testis cells compared to the BSU group. Sperm count and motility, and length density of seminiferous tubules were increased in CM group compared to the BSU group. AT-MSC-CM exhibited ameliorative effects on histopathologic changes of mouse testes exposed to BSU.


Assuntos
Infertilidade Masculina , Células-Tronco Mesenquimais , Animais , Bussulfano/toxicidade , Meios de Cultivo Condicionados/farmacologia , Masculino , Camundongos , Espermatogênese , Testículo
18.
Biomed Res Int ; 2021: 6854477, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34957307

RESUMO

Assessing differential item functioning (DIF) using the ordinal logistic regression (OLR) model highly depends on the asymptotic sampling distribution of the maximum likelihood (ML) estimators. The ML estimation method, which is often used to estimate the parameters of the OLR model for DIF detection, may be substantially biased with small samples. This study is aimed at proposing a new application of the elastic net regularized OLR model, as a special type of machine learning method, for assessing DIF between two groups with small samples. Accordingly, a simulation study was conducted to compare the powers and type I error rates of the regularized and nonregularized OLR models in detecting DIF under various conditions including moderate and severe magnitudes of DIF (DIF = 0.4 and 0.8), sample size (N), sample size ratio (R), scale length (I), and weighting parameter (w). The simulation results revealed that for I = 5 and regardless of R, the elastic net regularized OLR model with w = 0.1, as compared with the nonregularized OLR model, increased the power of detecting moderate uniform DIF (DIF = 0.4) approximately 35% and 21% for N = 100 and 150, respectively. Moreover, for I = 10 and severe uniform DIF (DIF = 0.8), the average power of the elastic net regularized OLR model with 0.03 ≤ w ≤ 0.06, as compared with the nonregularized OLR model, increased approximately 29.3% and 11.2% for N = 100 and 150, respectively. In these cases, the type I error rates of the regularized and nonregularized OLR models were below or close to the nominal level of 0.05. In general, this simulation study showed that the elastic net regularized OLR model outperformed the nonregularized OLR model especially in extremely small sample size groups. Furthermore, the present research provided a guideline and some recommendations for researchers who conduct DIF studies with small sample sizes.


Assuntos
Psicometria/métodos , Simulação por Computador , Humanos , Funções Verossimilhança , Modelos Logísticos , Aprendizado de Máquina , Modelos Estatísticos , Tamanho da Amostra , Inquéritos e Questionários
19.
Arch Iran Med ; 24(11): 828-836, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34841828

RESUMO

BACKGROUND: Hemodialysis (HD) patients face long-term complications which require ongoing dialysis and follow-up. The management of hypertension among HD populations has often been neglected. This study aimed at identifying the determinants of death in hypertensive HD (HTN-HD) patients. METHODS: In a multicenter retrospective cohort study (conducted from 2005 to 2018 in thirty-four HD centers affiliated with Shiraz University of Medical Sciences), the data of 725 HTN-HD patients who had at least 3 months of regular dialysis and follow-up were analyzed. Accelerated failure time mixture split-population (AFTMSP) regression was utilized to identify the factors with significant effects on long- and short-term overall survival (OS) separately. RESULTS: Among the different AFTMSP models, the extended generalized gamma (EGG) model outperformed the others. Sex (male: event time ratio [ETR]=1.30), initial vascular access type (arteriovenous fistula: ETR=1.50), and the type of membrane flux used for HD (high-flux: ETR=1.27) had important impacts on short-term OS. Moreover, age (OR=1.06), dialysis adequacy (Kt/ Vurea≤1.2: OR=2.30), initial vascular access type (central venous catheter: OR=2.08), serum sodium (OR=0.90) concentration, and potassium (OR=0.66) concentration had significant effects on long-term OS. CONCLUSION: The split-population analyses were able to demonstrate that the predictors of long-term OS were different from those of short-term OS. Although the superiority of the parametric EGG model was proved in this study, further research with different databases is suggested. Moreover, these findings can be considered by health policy decision-makers to create a new guideline to enhance the long-term OS of HTN-HD patients.


Assuntos
Hipertensão , Falência Renal Crônica , Humanos , Hipertensão/epidemiologia , Falência Renal Crônica/terapia , Masculino , Prognóstico , Diálise Renal , Estudos Retrospectivos , Fatores de Risco
20.
Opt Express ; 29(20): 32691-32699, 2021 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-34615334

RESUMO

We demonstrate single-shot nondiffracting light-sheet microscopy by the incoherent superposition of dispersed polychromatic light sources. We characterized our technique by generating a Bessel light-sheet with a supercontinuum light-source and a C-light-sheet using a diode laser, and demonstrated its applicability to fluorescence microscopy. We emphasize that our method is easily implementable and compatible with the requirements of high-resolution microscopy.

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