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1.
Thyroid ; 2024 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-38546971

RESUMO

Background: International guidelines recommend targeted screening to identify gestational thyroid dysfunction. However, currently used risk factors have questionable discriminative ability. We quantified the risk for thyroid function test abnormalities for a subset of risk factors currently used in international guidelines. Methods: We included prospective cohort studies with data on gestational maternal thyroid function and potential risk factors (maternal age, body mass index [BMI], parity, smoking status, pregnancy through in vitro fertilization, twin pregnancy, gestational age, maternal education, and thyroid peroxidase antibody [TPOAb] or thyroglobulin antibody [TgAb] positivity). Exclusion criteria were pre-existing thyroid disease and use of thyroid interfering medication. We analyzed individual participant data using mixed-effects regression models. Primary outcomes were overt and subclinical hypothyroidism and a treatment indication (defined as overt hypothyroidism, subclinical hypothyroidism with thyrotropin >10 mU/L, or subclinical hypothyroidism with TPOAb positivity). Results: The study population comprised 65,559 participants in 25 cohorts. The screening rate in cohorts using risk factors currently recommended (age >30 years, parity ≥2, BMI ≥40) was 58%, with a detection rate for overt and subclinical hypothyroidism of 59%. The absolute risk for overt or subclinical hypothyroidism varied <2% over the full range of age and BMI and for any parity. Receiver operating characteristic curves, fitted using maternal age, BMI, smoking status, parity, and gestational age at blood sampling as explanatory variables, yielded areas under the curve ranging from 0.58 to 0.63 for the primary outcomes. TPOAbs/TgAbs positivity was associated with overt hypothyroidism (approximate risk for antibody negativity 0.1%, isolated TgAb positivity 2.4%, isolated TPOAb positivity 3.8%, combined antibody positivity 7.0%; p < 0.001), subclinical hypothyroidism (risk for antibody negativity 2.2%, isolated TgAb positivity 8.1%, isolated TPOAb positivity 14.2%, combined antibody positivity 20.0%; p < 0.001) and a treatment indication (risk for antibody negativity 0.2%, isolated TgAb positivity 2.2%, isolated TPOAb positivity 3.0%, and combined antibody positivity 5.1%; p < 0.001). Twin pregnancy was associated with a higher risk of overt hyperthyroidism (5.6% vs. 0.7%; p < 0.001). Conclusions: The risk factors assessed in this study had poor predictive ability for detecting thyroid function test abnormalities, questioning their clinical usability for targeted screening. As expected, TPOAb positivity (used as a benchmark) was a relevant risk factor for (subclinical) hypothyroidism. These results provide insights into different risk factors for gestational thyroid dysfunction.

2.
J Clin Endocrinol Metab ; 109(3): e1290-e1298, 2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-37878891

RESUMO

CONTEXT: Triiodothyronine (T3) is the bioactive form of thyroid hormone. In contrast to thyroid-stimulating hormone and free thyroxine, we lack knowledge on the association of gestational T3 with adverse obstetric outcomes. OBJECTIVE: To investigate the associaiton of gestational free or total T3 (FT3 or TT3) with adverse obstetric outcomes. METHODS: We collected individual participant data from prospective cohort studies on gestational FT3 or TT3, adverse obstetric outcomes (preeclampsia, gestational hypertension, preterm birth and very preterm birth, small for gestational age [SGA], and large for gestational age [LGA]), and potential confounders. We used mixed-effects regression models adjusting for potential confounders. RESULTS: The final study population comprised 33 118 mother-child pairs of which 27 331 had data on FT3 and 16 164 on TT3. There was a U-shaped association of FT3 with preeclampsia (P = .0069) and a J-shaped association with the risk of gestational hypertension (P = .029). Higher TT3 was associated with a higher risk of gestational hypertension (OR per SD of TT3 1.20, 95% CI 1.08 to 1.33; P = .0007). A lower TT3 but not FT3 was associated with a higher risk of very preterm birth (OR 0.72, 95% CI 0.55 to 0.94; P = .018). TT3 but not FT3 was positively associated with birth weight (mean difference per 1 SD increase in TT3 12.8, 95% CI 6.5 to 19.1 g, P < .0001) but there was no association with SGA or LGA. CONCLUSION: This study provides new insights on the association of gestational FT3 and TT3 with major adverse pregnancy outcomes that form the basis for future studies required to elucidate the effects of thyroid function on pregnancy outcomes. Based on the current study, routine FT3 or TT3 measurements for the assessment of thyroid function during pregnancy do not seem to be of added value in the risk assessment for adverse outcomes.


Assuntos
Hipertensão Induzida pela Gravidez , Pré-Eclâmpsia , Nascimento Prematuro , Gravidez , Feminino , Humanos , Recém-Nascido , Tri-Iodotironina , Peso ao Nascer , Hipertensão Induzida pela Gravidez/epidemiologia , Hipertensão Induzida pela Gravidez/etiologia , Pré-Eclâmpsia/epidemiologia , Pré-Eclâmpsia/etiologia , Nascimento Prematuro/epidemiologia , Nascimento Prematuro/etiologia , Estudos Prospectivos , Hormônios Tireóideos , Tireotropina , Tiroxina
3.
J Clin Endocrinol Metab ; 109(3): 868-878, 2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-37740543

RESUMO

CONTEXT: Guidelines recommend use of population- and trimester-specific thyroid-stimulating hormone (TSH) and free thyroxine (FT4) reference intervals (RIs) in pregnancy. Since these are often unavailable, clinicians frequently rely on alternative diagnostic strategies. We sought to quantify the diagnostic consequences of current recommendations. METHODS: We included cohorts participating in the Consortium on Thyroid and Pregnancy. Different approaches were used to define RIs: a TSH fixed upper limit of 4.0 mU/L (fixed limit approach), a fixed subtraction from the upper limit for TSH of 0.5 mU/L (subtraction approach) and using nonpregnancy RIs. Outcome measures were sensitivity and false discovery rate (FDR) of women for whom levothyroxine treatment was indicated and those for whom treatment would be considered according to international guidelines. RESULTS: The study population comprised 52 496 participants from 18 cohorts. Compared with the use of trimester-specific RIs, alternative approaches had a low sensitivity (0.63-0.82) and high FDR (0.11-0.35) to detect women with a treatment indication or consideration. Sensitivity and FDR to detect a treatment indication in the first trimester were similar between the fixed limit, subtraction, and nonpregnancy approach (0.77-0.11 vs 0.74-0.16 vs 0.60-0.11). The diagnostic performance to detect overt hypothyroidism, isolated hypothyroxinemia, and (sub)clinical hyperthyroidism mainly varied between FT4 RI approaches, while the diagnostic performance to detect subclinical hypothyroidism varied between the applied TSH RI approaches. CONCLUSION: Alternative approaches to define RIs for TSH and FT4 in pregnancy result in considerable overdiagnosis and underdiagnosis compared with population- and trimester-specific RIs. Additional strategies need to be explored to optimize identification of thyroid dysfunction during pregnancy.


Assuntos
Hipotireoidismo , Testes de Função Tireóidea , Gravidez , Humanos , Feminino , Prevalência , Hipotireoidismo/diagnóstico , Hipotireoidismo/epidemiologia , Tiroxina , Tireotropina , Valores de Referência
4.
J Family Reprod Health ; 17(2): 80-85, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37547778

RESUMO

Objective: Metabolic syndrome is a risk factor affecting reproductive health and pregnant outcomes. So far, the effect of this syndrome on the success rate of assisted reproduction techniques (ART) has not been investigated. The aim of this study was to investigate the relationship between metabolic syndrome and the success rate of ART in infertile women in Isfahan. Materials and methods: A prospective cohort study performed on 147 women candidates using in-vitro fertilization/intra cytoplasmic sperm injection (IVF/ICSI) and/or ICSI methods referred to Isfahan Infertility Center in two groups with metabolic syndrome(n=49) without metabolic syndrome(n=98), by convenience sampling methods in Isfahan, Iran in 2018. Body mass index (BMI) and waist, abdominal circumference, Serum triglyceride (TG), cholesterol and FBS were measured. If ßHCG test was positive (day 15-16 after ART), transvaginal sonography (TVS) was done 15 days later. Pregnant women were followed up to the 20th week of pregnancy. To analyze, t-test, chi-square and logistic regression tests were used. Results: The frequency of metabolic syndrome was 33.4% (n=49). The frequency of ART was not significantly different between women with and without metabolic syndrome (p=0.321). The relative frequency of pregnancy (p=0.907) and abortion (p=0.896) did not show a significant difference between the two groups. Independent t-test showed that the mean FBS, HDL, TG, systolic and diastolic BP, abdominal circumference and BMI in the studied units did not differ significantly based on the occurrence of pregnancy and abortion. Conclusion: According to the results of this study, there was no significant difference between the indicators of metabolic syndrome and the success rate of ART in achieving, pregnancy and pregnant outcomes in the first twenty weeks of pregnancy.

6.
Int J Biol Macromol ; 245: 125510, 2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-37353120

RESUMO

The objectives were to identify the functional domains of a potential oncoprotein, cell migration inducing hyaluronidase 2 (CEMIP2), evaluate its expression levels and roles in colorectal cancer (CRC), and develop an aptamer-based nanoparticle for targeted therapy. Data mining on TCGA identified that CEMIP2 might play oncogenic roles in CRC. In a local cohort, CEMIP2 mRNA levels significantly stepwise increase in CRC patients with higher stages, and high CEMIP2 confers worse disease-free survival. In addition, CEMIP2 mRNA levels significantly correlated to hyaluronan levels in sera from CRC patients. Deletion mapping identified that CEMIP2 containing G8 and PANDER-like domains preserved hyaluronidase activity and oncogenic roles, including cell proliferation, anchorage-independent cell growth, cell migration and invasion, and human umbilical vein endothelial cell (HUVEC) tube formation in CRC-derived cells. A customized monoclonal mouse anti-human CEMIP2 antibody probing the PANDER-like domain (anti-289307) counteracted CEMIP2-mediated carcinogenesis in vitro. Cell-SELEX pinpointed an aptamer, aptCEMIP2(101), specifically interacted with the full-length CEMIP2, potentially involving its 3D structure. Treatments with aptCEMIP2(101) significantly reduced CEMIP2-mediated tumorigenesis in vitro. Mesoporous silica nanoparticles (MSN) carrying atpCEMIP2(101) and Dox were fabricated. Dox@MSN, MSN-aptCEMIP2(101), and Dox@MSN-aptCEMIP2(101) significantly suppressed tumorigenesis in vitro compared to the Mock, while Dox@MSN-aptCEMIP2(101) showed substantially higher effects compared to Dox@MSN and MSN-aptCEMIP2(101) in CRC-derived cells. Our study identified a novel oncogene and developed an effective aptamer-based targeted therapeutic strategy.


Assuntos
Neoplasias Colorretais , Nanopartículas , Humanos , Camundongos , Animais , Sistemas de Liberação de Medicamentos , Portadores de Fármacos/química , Hialuronoglucosaminidase , Doxorrubicina/química , Oligonucleotídeos , Nanopartículas/química , Carcinogênese , Neoplasias Colorretais/tratamento farmacológico , Dióxido de Silício/química , Porosidade , Citocinas
7.
J Educ Health Promot ; 11: 293, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36438989

RESUMO

BACKGROUND: Osteoporosis, the fourth most common disease in the world, affects the elderly and postmenopausal women and imposes a great financial and social burden on individuals and society. Furthermore, it has a significant impact on the quality of patients' life. This study tries to take an effective step toward improving the quality of patients' life by developing and evaluating the self-care program of women with osteoporosis. MATERIALS AND METHODS: In this research, a hybrid sequential design of quantitative and qualitative type consisting of three phases is used. This mixed-method study aimed to develop and evaluate a self-care program for women with osteoporosis. CONCLUSION: Familiarity with the needs of these patients and the use of self-care programs and considering social, cultural, and psychological factors could be effective steps to improve the health of women with osteoporosis. These steps can improve the quality of life and reduce the costs of treatment for this group of women.

8.
Int J Biol Macromol ; 219: 1163-1179, 2022 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-36058386

RESUMO

Biofilms are communities of microorganisms that can be harmful and/or beneficial, depending on location and cell content. Since in most cases (such as the formation of biofilms in laboratory/medicinal equipment, water pipes, high humidity-placed structures, and the food packaging machinery) these bacterial and fungal communities are troublesome, researchers in various fields are trying to find a promising strategy to destroy or slow down their formation. In general, anti-biofilm strategies are divided into the plant-based and non-plant categories, with the latter including nanoparticles, bacteriophages, enzymes, surfactants, active peptides and free fatty acids. In most cases, using a single strategy will not be sufficient to eliminate biofilm, and consequently, two or more strategies will inevitably be used to deal with this unwanted phenomenon. According to the analysis of potential biofilm inhibition strategies, the best option for the food industry would be the use of hydrolase enzymes and peptides extracted from natural sources. This article represents a systematic review of the previous efforts made in these directions.


Assuntos
Ácidos Graxos não Esterificados , Hidrolases , Antibacterianos/farmacologia , Bactérias , Biofilmes , Indústria Alimentícia , Peptídeos/farmacologia , Tensoativos/farmacologia
9.
J Clin Endocrinol Metab ; 107(10): 2925-2933, 2022 09 28.
Artigo em Inglês | MEDLINE | ID: mdl-35861700

RESUMO

CONTEXT: Interpretation of thyroid function tests during pregnancy is limited by the generalizability of reference intervals between cohorts due to inconsistent methodology. OBJECTIVE: (1) To provide an overview of published reference intervals for thyrotropin (TSH) and free thyroxine (FT4) in pregnancy, (2) to assess the consequences of common methodological between-study differences by combining raw data from different cohorts. METHODS: (1) Ovid MEDLINE, EMBASE, and Web of Science were searched until December 12, 2021. Studies were assessed in duplicate. (2) The individual participant data (IPD) meta-analysis was performed in participating cohorts in the Consortium on Thyroid and Pregnancy. RESULTS: (1) Large between-study methodological differences were identified, 11 of 102 included studies were in accordance with current guidelines; (2) 22 cohorts involving 63 198 participants were included in the meta-analysis. Not excluding thyroid peroxidase antibody-positive participants led to a rise in the upper limits of TSH in all cohorts, especially in the first (mean +17.4%; range +1.6 to +30.3%) and second trimester (mean +9.8%; range +0.6 to +32.3%). The use of the 95th percentile led to considerable changes in upper limits, varying from -10.8% to -21.8% for TSH and -1.2% to -13.2% for FT4. All other additional exclusion criteria changed reference interval cut-offs by a maximum of 3.5%. Applying these findings to the 102 studies included in the systematic review, 48 studies could be used in a clinical setting. CONCLUSION: We provide an overview of clinically relevant reference intervals for TSH and FT4 in pregnancy. The results of the meta-analysis indicate that future studies can adopt a simplified study setup without additional exclusion criteria.


Assuntos
Iodeto Peroxidase , Tiroxina , Feminino , Humanos , Gravidez , Valores de Referência , Testes de Função Tireóidea , Glândula Tireoide , Tireotropina
10.
Womens Midlife Health ; 8(1): 7, 2022 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-35791001

RESUMO

INTRODUCTION: Breast cancer is one of the most prevalent cancers among women in Isfahan, Iran; however, its prevention is not desirable in this city. This disease poses several health, social and economic challenges for women. To promote women's self-care in breast cancer prevention, this study aims to design, implement and evaluate a self-care program among women in Isfahan through using a community-based participatory action research method. METHODS: The present study is based on a community-based participatory action research approach. In this study, the participatory action research includes four general phases of organizing, action planning, action, and rethinking. These phases are summarized as follows: In the organizing phase, the needs of the participants and the action research settings are examined. This means that the current situation is identified and the views of the process owners are assessed. In the action planning phase, using the results of the first phase, some strategies are designed to promote self-care behaviors in the prevention of breast cancer among women in Isfahan. In the implementation phase, the selected strategies are implemented with the help of the process owners. Finally, in the rethinking phase, the results of the implementation of the strategies are monitored and evaluated. This cycle continues until the intended results are achieved. DISCUSSION: Changing the role of individuals from a passive status to an aware and active status in the care process requires motivation, responsibility, and active participation of individuals in the disease control process. Moreover, many cultural and social factors affect the active participation of Iranian women. Therefore, individuals can be involved in promoting their health using a community-based participatory action research approach.

11.
Nanomaterials (Basel) ; 12(9)2022 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-35564311

RESUMO

More than 2 years have passed since the SARS-CoV-2 outbreak began, and many challenges that existed at the beginning of this pandemic have been solved. Some countries have been able to overcome this global challenge by relying on vaccines against the virus, and vaccination has begun in many countries. Many of the proposed vaccines have nanoparticles as carriers, and there are different nano-based diagnostic approaches for rapid detection of the virus. In this review article, we briefly examine the biology of SARS-CoV-2, including the structure of the virus and what makes it pathogenic, as well as describe biotechnological methods of vaccine production, and types of the available and published nano-based ideas for overcoming the virus pandemic. Among these issues, various physical and chemical properties of nanoparticles are discussed to evaluate the optimal conditions for the production of the nano-mediated vaccines. At the end, challenges facing the international community and biotechnological answers for future viral attacks are reviewed.

12.
J Educ Health Promot ; 11: 82, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35573636

RESUMO

Role of clinical skill training in the formation of skills and professional competencies of midwifery students is important. Hence, the use of "training new methods are essential in clinical settings." This study aimed at determining the effectiveness of simulation training in obstetric emergencies. In this meta-analysis study, international databases of Web of Science, Scopous, Proquest, and PubMed and Iranian databases such as Irandoc, Magiran, and SID were searched for studies published between 2000 and 2020 using related keywords. Based on the consortium checklist, the full text of the selected articles was reviewed and in case of a specific score, the article was analyzed. The results show that, out of 420 studies after applying the inclusion and exclusion criteria, only nine clinical trial articles were reviewed. Studies were conducted in Iran, the United States, France, China, and Chicago. The results of meta-analysis showed that the simulation training method can be effective in managing midwifery emergencies. Hence, the use of simulation training method can be effective in various areas of learning related to obstetric emergencies.

13.
Int J Urol ; 28(11): 1178-1187, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34374132

RESUMO

OBJECTIVE: To examine the expression levels of the glycosyltransferase 8 domain containing protein 2 and its clinical implications in urothelial carcinoma patients. METHODS: Data mining, immunohistochemistry together with H-score calculation was carried out to evaluate the glycosyltransferase 8 domain containing protein 2 levels on tissue specimens from urothelial carcinoma patients, retrospectively. Correlations between glycosyltransferase 8 domain containing protein 2 H-score and imperative clinicopathological factors were measured. The indication of glycosyltransferase 8 domain containing protein 2 level on disease-specific and metastasis-free survivals were next analyzed. RESULTS: In upper tract urothelial carcinomas (n = 340) and bladder urothelial carcinomas (n = 295), 170 (50%) and 148 (50%) patients, respectively, were identified to have high glycosyltransferase 8 domain containing protein 2 expression. The glycosyltransferase 8 domain containing protein 2 levels were correlated to several clinicopathological characteristics and patient survival. Upregulation of the glycosyltransferase 8 domain containing protein 2 was correlated to primary tumor (P < 0.001), nodal metastasis (P < 0.001), histological grade (P < 0.001), vascular invasion (P < 0.001), perineural invasion (P < 0.05) and mitotic rate (P < 0.001). High glycosyltransferase 8 domain containing protein 2 levels independently predicted poor disease-specific survival (P = 0.049) and metastasis-free survival (P = 0.008) in upper tract urothelial carcinoma and urinary bladder urothelial carcinoma, respectively. Gene Ontology enrichment analysis additionally showed that multiple biological processes were enriched including "ECM organization" (Gene Ontology:0030198), "extracellular structure organization" (Gene Ontology:0043062), "biological adhesion" (Gene Ontology:0022610), "cell adhesion" (Gene Ontology:0007155), "collagen fibril organization" (Gene Ontology:0030199) and "vasculature development" (Gene Ontology:0001944). CONCLUSIONS: The present findings suggest that upregulation of the glycosyltransferase 8 domain containing protein 2 is an independent and disadvantageous prognosticator in urothelial carcinoma. High glycosyltransferase 8 domain containing protein 2 level might play a crucial role in progression of urothelial carcinoma.


Assuntos
Carcinoma de Células de Transição , Glicosiltransferases , Neoplasias da Bexiga Urinária , Biomarcadores Tumorais , Glicosiltransferases/genética , Humanos , Prognóstico , Estudos Retrospectivos
16.
Iran J Nurs Midwifery Res ; 25(5): 387-392, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33344209

RESUMO

BACKGROUND: Since endothelial dysfunction is related to atherosclerosis, this study was planned to determine the effect of type of delivery on Nitric Oxide (NO) metabolites and endothelial function. MATERIALS AND METHODS: This Cohort study was conducted in 2015 in selected hospitals of Isfahan. 88 nulliparous women with gestational age of 39 weeks and above were enrolled in this study using convenience sampling method and finally, after giving birth, 51 mothers with vaginal delivery, 21 with urgent C-section and 13 with elective C-section were considered for data analysis. The serum levels of NO metabolites were measured in the laboratory with standard kits and data was analyzed using student and paired t-test, one-way ANOVA, and Chi-square test. The significance level was considered less than 0.05 for all tests. RESULTS: The NO metabolites levels in mothers who had vaginal delivery or urgent C-section showed a significant difference before and after delivery (normal vaginal delivery (NVD): t50 = 5.61, p < 0.001, Urgent C-section: t23 = 5.38, p < 0.001). But those with elective C-section showed no significant difference in the nitrate and total nitrite levels before and after delivery (p > 0.05). CONCLUSIONS: Since reduction in serum levels of NO metabolites may possibly indicate endothelial dysfunction and predict cardiovascular disease, especially atherosclerosis in the future, it could be concluded that, childbirth, regardless of the type of delivery, could damage the endothelial cells but C-section (urgent or elective) could cause more disruption than vaginal delivery.

17.
J Res Med Sci ; 25: 13, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32174985

RESUMO

BACKGROUND: Currently, it is shown that pregnancy may have an impact on the thyroid that can be leading to pregnancy complications such as abortion, preeclampsia, and preterm delivery. The objective was to compare the thyroid volume, number and characteristics of thyroid nodules, and prevalence of diffuse thyroid diseases in a sample of Iranian pregnant women in the first trimester to nonpregnant women. MATERIALS AND METHODS: This case-control study was conducted on 298 pregnant and 290 nonpregnant women. Thyroid volume, maximum diameter of thyroid nodules and prevalence of moderate to highly suspicious thyroid nodules, Hashimoto's appearance and goiter were assessed using thyroid ultrasonography. Antithyroperoxidase (TPO) antibodies were measured if the sonographic features were highly suggested for Hashimoto's thyroiditis. RESULTS: The mean of total thyroid volume in pregnant and nonpregnant women was 6 and 6.5 ml, respectively (P = 0.053), and the median (interquartile range) was 6.2 and 5.5, respectively. Nodules were observed in 16.4% of pregnant and 16.6% of nonpregnant women (P = 0.845). Hashimoto's thyroiditis was detected in 6.7% of pregnant and 12.4% of nonpregnant women (P = 0.013). Anti-TPO antibodies were detected in 5% of pregnant and 9.3% of nonpregnant women (P = 0.034). CONCLUSION: The thyroid volume and nodule characteristics in the first trimester of pregnancy were similar to nonpregnant women. Hashimoto's thyroiditis and anti-TPO antibodies in pregnant women were significantly lower than in nonpregnant women.

18.
RSC Adv ; 10(50): 29885-29899, 2020 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-35518209

RESUMO

Insulin rapidly fibrillates in the presence of amyloid seeds from different sources. To address its cross-reactivity we chose the seeds of seven model proteins and peptides along with the seeds of insulin itself. Model candidates were selected/designed according to their size, amino acid sequence, and hydrophobicity. We found while some seeds provided catalytic ends for inducing the formation of non-native insulin conformers and increase fibrillation, others attenuated insulin fibrillation kinetics. We also observed competition between the intermediate insulin conformers which formed with urea and amyloid seeds in entering the fibrillogenic pathway. Simultaneous incubation of insulin with urea and amyloid seeds resulted in the formation of nearly similar insulin intermediate conformers which synergistically enhance insulin fibrillation kinetics. Given these results, it is highly likely that, structurally, there is a specific intermediate in different pathways of insulin fibrillation that governs fibrillation kinetics and morphology of the final mature fibril. Overall, this study provides a novel mechanistic insight into insulin fibrillation and gives new information on how seeds of different proteins are capable of altering insulin fibrillation kinetics and morphology. This report, for the first time, tries to answer an important question that why fibrillation of insulin is either accelerated or attenuated in the presence of amyloid fibril seeds from different sources.

19.
Iran J Nurs Midwifery Res ; 24(5): 360-364, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31516522

RESUMO

BACKGROUND: Gestational diabetes is the second common disorder in pregnancy period, which is detected in 24-28 weeks of gestational age through screening tests. Low-grade systematic inflammation is associated with an increased risk of type 2 diabetes. C-Reactive Protein (CRP), an acute phase protein produced by hepatocytes, may be associated with diabetes. This study aimed to investigate serum levels of CRP in women with Gestational Diabetes Mellitus (GDM) and impaired glucose tolerance test compared with control subjects. MATERIALS AND METHODS: This observational longitudinal study was conducted on 176 pregnant women in Isfahan. After administration of a CRP test in these women in the first trimester, a screening test of Glucose Challenge Test (GCT) with 50-g oral glucose was conducted in 24-28 weeks of gestational age. Then, CRP levels and GCT were compared. RESULTS: Serum CRP levels were not significantly correlated with positive GCT among the women. In GDM patients, there was not a significant correlation between CRP and BMI. CONCLUSIONS: There was no significant correlation between maternal serum CRP level and gestational diabetes. Maternal serum CRP level in the first trimester cannot predict Intolerance Glucose Test (IGT) in 26-30 weeks of gestational age.

20.
Cell Biochem Biophys ; 77(4): 343-355, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31535344

RESUMO

The elevated lenticular level of methylglyoxal (MGO) in diabetic patients is an important risk factor for the development of age-related (senile) cataract disorders. Carnosine (ß-alanyl L-histidine), a natural antioxidant dipeptide product, has been indicated to prevent the development of cataract diseases. Therefore, it is possible that the anti-cataract activity of this naturally occurring compound is mediated by its anti-glycoxidation effect. In this study, the eye lens proteins were treated with MGO in the presence of carnosine. Then, sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) analysis and several spectroscopic evaluations were used with the aim to investigate the possible inhibitory activity of carnosine against the MGO-induced structural damages of eye lens proteins. Our results indicated that MGO causes a substantial structural alteration in the lens proteins. The results of fluorescence assessments also suggested that MGO-induced structural changes were accompanied with the formation of additional chromophores in the protein structure. Also, in the presence of carnosine, a notable reduction in the protein structural damages was observed. Our results may highlight an important protective role of carnosine against MGO-induced structural insults in the lens proteins. This study suggests carnosine supplementation as a possible preventive strategy against development of the diabetic cataracts in human.


Assuntos
Carnosina/farmacologia , Cristalino/efeitos dos fármacos , Aldeído Pirúvico/farmacologia , Animais , Bovinos , Cristalinas/química , Cristalinas/metabolismo , Eletroforese em Gel de Poliacrilamida , Cristalino/química , Cristalino/metabolismo , Estabilidade Proteica , Estrutura Secundária de Proteína , Espectrofotometria
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