Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 94
Filtrar
1.
Cell Tissue Bank ; 2021 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-33608835

RESUMO

Cryoprotectant-free vitrification is a common method for spermatozoa cryopreservation by direct plunging into liquid nitrogen. However, the commercial liquid nitrogen could be potentially contaminated by microorganisms. Warming temperature plays an essential role for quality of human spermatozoa after vitrification. This study aimed to evaluate comparatively a quality spermatozoa after vitrification in liquid nitrogen and clean liquid air as well as with two warming rates: at 42 °C and 45 °C. After performing of routine swim-up of normozoospermia samples, spermatozoa from the same ejaculate were divided into two groups: vitrified in liquid nitrogen (LN) and sterile liquid air (LA). Spermatozoa of LN group were warmed at 42 °C, and spermatozoa of LA groups were divided and warmed at 42 °C (LA42) and 45 °C (LA45). Then spermatozoa motility, reactive oxygen species (ROS), mitochondrial membrane potential (MMP), reactive nitrogen species (RNS), and viability were assessed. It was no found significant differences in quality of spermatozoa from LN and LA groups in the motility, ROS, MMP, RNS rates after warming at 42 °C. A tendency to obtain better spermatozoa quality was found with using of warming by 42 °C in comparison with 45 °C. It was concluded that cryoprotectant-free vitrification by direct dropping of human spermatozoa into clean liquid air can be used as an alternative to cooling in liquid nitrogen. Warming of spermatozoa at 42 °C allows to preserve the spermatozoa physiological parameters.

2.
Eur Heart J ; 2021 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-33527989

RESUMO

AIMS : Little is known about the relation between the long-term joint exposure to various ambient air pollutants and the incidence of heart failure (HF). We aimed to assess the joint association of various air pollutants with HF risk and examine the modification effect of the genetic susceptibility. METHODS AND RESULTS : This study included 432 530 participants free of HF, atrial fibrillation, or coronary heart disease in the UK Biobank study. All participants were enrolled from 2006 to 2010 and followed up to 2018. The information on particulate matter (PM) with diameters ≤2.5 µm (PM2.5), ≤10 µm (PM10), and between 2.5 and 10 µm (PM2.5-10) as well as nitrogen oxides (NO2 and NOx) was collected. We newly proposed an air pollution score to assess the joint exposure to the five air pollutants through summing each pollutant concentration weighted by the regression coefficients with HF from single-pollutant models. We also calculated the weighted genetic risk score of HF. During a median of 10.1 years (4 346 642 person-years) of follow-up, we documented 4201 incident HF. The hazard ratios (HRs) [95% confidence interval (CI)] of HF for a 10 µg/m3 increase in PM2.5, PM10, PM2.5-10, NO2, and NOx were 1.85 (1.34-2.55), 1.61 (1.30-2.00), 1.13 (0.80-1.59), 1.10 (1.04-1.15), and 1.04 (1.02-1.06), respectively. We found that the air pollution score was associated with an increased risk of incident HF in a dose-response fashion. The HRs (95% CI) of HF were 1.16 (1.05-1.28), 1.19 (1.08-1.32), 1.21 (1.09-1.35), and 1.31 (1.17-1.48) in higher quintile groups compared with the lowest quintile of the air pollution score (P trend <0.001). In addition, we observed that the elevated risk of HF associated with a higher air pollution score was strengthened by the genetic susceptibility to HF. CONCLUSION : Our results indicate that the long-term joint exposure to various air pollutants including PM2.5, PM10, PM2.5-10, NO2, and NOx is associated with an elevated risk of incident HF in an additive manner. Our findings highlight the importance to comprehensively assess various air pollutants in relation to the HF risk.

3.
Cryobiology ; 2021 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-33422478

RESUMO

The protocol of aseptic cryoprotectant-free vitrification on human spermatozoa is well documented. However, data about the effect of permeable cryoprotectants at this procedure is limited. Presented study aimed to test the aseptic capillary vitrification technologies using permeable cryoprotectant-included or cryoprotectant-free media. Thirty-two normal samples were included and analyzed after vitrification in three different media and thawing. Three treatment groups were formed: Group 1, basic medium; Group 2, basic medium with 0.25 M sucrose; Group 3, basic medium with glycerol. Before plunging into liquid nitrogen, capillaries were filled by 10 µl of spermatozoa suspension and isolated from liquid nitrogen by location in hermetically closed 0.25 ml straws. Progressive motility, plasma membrane integrity, total motility/viability after 24, 48 and 72 h in vitro culture, apoptosis and mitochondrial membrane potential (ΔΨm) were determined after thawing at 42 °C. Progressive motility of spermatozoa in groups 1, 2, 3 was 24.9 ± 1.7%, 34.5 ± 2.8% and 34.0 ± 1.4%, respectively (P1-2,3<0.05). The plasma membrane integrity of spermatozoa in groups 2 and 3 (48.4 ± 2.9% and 45.5 ± 3.9%, respectively) was higher than in Group 1 (33.3 ± 2.1%, P < 0.05). After 24 h, 48 h and 72 h in vitro culture, the total motility and viability of spermatozoa in Group 1 was significantly lower than Group 2 and Group 3. The apoptosis rate in Group 3 (44.5 ± 3.0%) and Group 2 (47.7 ± 4.1%) were lower than in Group 1 (52.5 ± 4.4%; P < 0.05). ΔΨm rates in Group 3 and Group 2 were higher than in Group 1 (P < 0.05) with no statistical differences between this parameter in Group 2 and Group 3 (P > 0.1). In conclusion, supplementation of medium for aseptic capillary technology for cryoprotectant-free vitrification of human spermatozoa by permeable cryoprotectant does not improve the quality of spermatozoa after warming.

4.
Metab Eng ; 64: 95-110, 2021 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-33493644

RESUMO

Methanol is assimilated through the serine cycle to generate acetyl-CoA without carbon loss. However, a highly active serine cycle requires high consumption of reducing equivalents and ATP, thereby leading to the impaired efficiency of methanol conversion to reduced chemicals. In the present study, a genome-scale flux balance analysis (FBA) predicted that the introduction of the heterologous ribulose monophosphate (RuMP) cycle, a more energy-efficient pathway for methanol assimilation, could theoretically increase growth rate by 31.3% for the model alphaproteobacterial methylotroph Methylorubrum extorquens AM1. Based on this analysis, we constructed a novel synergistic assimilation pathway in vivo by incorporating the RuMP cycle into M. extroquens metabolism with the intrinsic serine cycle. We demonstrated that the operation of the synergistic pathway could increase cell growth rate by 16.5% and methanol consumption rate by 13.1%. This strategy rewired the central methylotrophic metabolism through adjusting core gene transcription, leading to a pool size increase of C2 to C5 central intermediates by 1.2- to 3.6-fold and an NADPH cofactor improvement by 1.3-fold. The titer of 3-hydroxypropionic acid (3-HP), a model product in the newly engineered chassis of M. extorquens AM1, was increased to 91.2 mg/L in shake-flask culture, representing a 3.1-fold increase compared with the control strain with only the serine cycle. The final titer of 3-HP was significantly improved to 0.857 g/L in the fed-batch bioreactor, which was more competitive compared with the other 3-HP producers using methane and CO2 as C1 sources. Collectively, our current study demonstrated that engineering the synergistic methanol assimilation pathway was a promising strategy to increase the carbon assimilation and the yields of reduced chemicals in diverse host strains for C1 microbial cell factories.

5.
Reprod Biol Endocrinol ; 19(1): 8, 2021 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-33441149

RESUMO

BACKGROUND: Ovarian hyperstimulation syndrome (OHSS) is a common disease during controlled ovarian hyperstimulation treatment. However, the obstetric and neonatal outcomes of this group of patients are unknown. The aim of this study was to explore the effects of late moderate-to-critical OHSS on obstetric and neonatal outcomes. METHODS: This prospective observational study included 17,537 patients who underwent IVF/ICSI-fresh embryo transfer (ET) between June 2012 and July 2016 and met the inclusion criteria, including 7,064 eligible patients diagnosed with clinical pregnancy. Ultimately, 6,356 patients were allocated to the control group, and 385 patients who were hospitalized and treated at the center for late moderate-to-critical OHSS were allocated to the OHSS group. Then, propensity score matching analysis was performed, matching nine maternal baseline covariates and the number of multiple gestations; 385 patients with late moderate-to-critical OHSS were compared with a matched control group of 1,540 patients. The primary outcomes were the live birth rate, preterm delivery rate, miscarriage rate, gestational age at birth (weeks), obstetric complications and neonatal complications. RESULTS: The duration of gestation in the matched control group was significantly higher than that in the OHSS group. The live birth delivery rate did not significantly differ between the OHSS and matched control groups. The incidence rates of the obstetric complications venous thrombosis (VT) and gestational diabetes mellitus (GDM), neonatal complications and the number of neonates admitted to the NICU were significantly higher in the OHSS group than in the matched control group. CONCLUSIONS: Pregnant women undergoing IVF with fresh ET whose course is complicated by late moderate-to-critical OHSS appear to experience shortened gestation and increased obstetrical and neonatal complications compared with matched controls whose course is not complicated by OHSS. However, the live birth rate, average neonatal weight, and incidence rates of premature delivery, miscarriage, early abortion, hypertensive disorder of pregnancy (HDP), placenta previa (PP), intrahepatic cholestasis of pregnancy (ICP), and low neonatal birth weight (LBW) did not differ significantly between the two groups.

6.
Eur J Obstet Gynecol Reprod Biol ; 258: 258-264, 2021 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-33485262

RESUMO

OBJECTIVE: Primordial follicles in premature ovarian failure (POF) patients are very difficult to be activated spontaneously, so that mature oocytes are difficult to be obtained for in vitro fertilization. The aim of our review is to analyze and to systematize the published data regarding effectiveness of different strategies for in vitro activation of cryopreserved ovarian tissue. STUDY DESIGN: According to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, a review of the literature was performed for all relevant full-text articles published in PubMed in English. Meta-analysis conducted using STATA 14.0. The random-effects model was used to combine 8 study results because the examination of heterogeneity was minimal. RESULTS: One hundred and seventy seven patients after in vitro activation treatment (IVA) of ovarian tissue had accumulatively 26 pregnancies through IVF or natural pregnancy and then produced 18 live births. The random-effects model showed that the total clinical pregnancy and baby born rates reported in 8 studies evidence about effectiveness of IVA. CONCLUSION: In vitro activation of primordial follicles as a new potential treatment for ovarian disorder patients, can be a promising option for fertility preservation. Drug-free activation of ovarian tissue in comparison with drug-included activation seemed to be more efficient.

7.
Carbohydr Polym ; 255: 117353, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33436193

RESUMO

Preparation of renewable, insoluble, and transparent films is still a major challenge for the application of soft electronics and packing industry. Herein, a "green" protocol for preparation of such a film based on carboxymethyl cellulose (CMC) is presented, where acid assistant freeze-thaw method was used in combination with drying. We have shown that the resultant films displayed flexibility, high light transmittance (above 90 %), insolubility, high mechanical performances (elastic modulus of 29.6 MPa), and good thermal stability. Moreover, CMC film/filter paper was fabricated, and the waterproof and mechanical properties of which were investigated. This approach offers a promising route to the fabrication of flexible and transparent films with good waterproof properties based on soluble biomass.

8.
Gynecol Endocrinol ; : 1-5, 2021 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-33438480

RESUMO

OBJECTIVE: To investigate whether the ratio of the serum progesterone level on the day of human chorionic gonadotrophin (hCG) administration to the basal serum progesterone level (PhCG/Pbasal) is a predictor of pregnancy outcome during in vitro fertilization (IVF). METHODS: A total of 12,708 cycles were performed in 9747 patients between 19 and 36 years of age who were undergoing controlled ovarian stimulation from October 2011 to July 2016 for their first or second attempts at IVF followed by fresh embryo transfer (ET). hCG was administered 36 h before oocyte retrieval to trigger final oocyte maturation. The serum progesterone level was measured on menstrual cycle days 2-4 (basal progesterone, Pbasal) and on the day of hCG administration (PhCG). PhCG/Pbasal was calculated. Live birth rates were compared among various ordinal PhCG/Pbasal intervals (< 0.5, 0.5-1.0, 1.0-1.5, 1.5-2.0, 2.0-2.5, > 2.5). RESULTS: The average age of the patients recruited was 29.9 years. The average basal progesterone level was 0.8 ng/ml, while the average progesterone level on the day of hCG administration was 0.9 ng/ml. The live birth rates (according to the abovementioned ordinal PhCG/Pbasal intervals) were 47.3, 49.9, 47.8, 46.3, 45.5 and 44.0%, respectively. The live birth rates were significantly higher for patients with PhCG/Pbasal between 0.5-1.0 (OR = 1.14, 95% CI, 1.02-1.27, p = .02). CONCLUSIONS: PhCG/Pbasal between 0.5-1.0 predicts a higher live birth rate in IVF. Both PhCG/Pbasal and P on hCG day is less predictive value for predicting live birth rate.

9.
Addiction ; 2021 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-33404152

RESUMO

BACKGROUND AND AIMS: China has a high smoking prevalence, but lacks effective tobacco control interventions. In 2015, comprehensive policies that incorporated all six aspects of MPOWER were implemented in Beijing and were considered the strictest tobacco control policy implemented in China to date. Decreases in the prevalence of active smoking and secondhand smoke (SHS) exposure were observed thereafter. This study aimed to evaluate the impact of Beijing's 2015 tobacco control policy package on cardiovascular diseases (CVDs). DESIGN: Interrupted time-series study. SETTING: Beijing, China. PARTICIPANTS: A total of 17.7 million employees enrolled in Urban Employee Basic Medical Insurance (UEBMI) between January 2013 to June 2017. INTERVENTIONS: Beijing's 2015 comprehensive tobacco policy package, combining a complete ban on smoking in indoor public places, cessation support, more comprehensive bans on advertising, and tax rises. MEASUREMENTS: The main outcome was hospital admissions for all CVDs and five major cause-specific CVDs, including ischaemic heart disease (IHD), heart failure (HF), heart rhythm disturbances (HRDs), stroke and other cerebrovascular diseases (CBDs). The absolute number and proportion of reductions in the number of hospital admissions after the policies are reported. FINDINGS: A total of 419 875 hospital admissions for CVD were identified. In total, 13.4% [95% confidence interval (CI) = 11.5%, 15.3%] of hospital admissions for CVD were averted by the tobacco control policies. For major cause-specific CVDs, significant hospital admission reductions occurred for IHD (5.4%, 95% CI = 2.6%, 8.3%), stroke (21.2%, 95% CI = 17.8%, 24.6%) and other CBDs (25.9%, 95% CI = 20.8%, 31.0%), but not for HF (4.7%, 95% CI = -4.2%, 13.5%) or HRDs (4.7%, 95% CI = -2.9%, 12.3%). CONCLUSIONS: Beijing's 2015 tobacco control policy package appears to have been associated with a more than 10% reduction in all cardiovascular hospital admissions, including a more than 20% reduction in admissions for cerebrovascular diseases.

10.
Methods Mol Biol ; 2221: 223-260, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-32979207

RESUMO

The surgical model of destabilization of the medial meniscus (DMM) has become a gold standard for studying the onset and progression of post-traumatic osteoarthritis (OA). The DMM model mimics clinical meniscal injury, a known predisposing factor for the development of human OA, and permits the study of structural and biological changes over the course of the disease. In addition, when applied to genetically modified or engineered mouse models, this surgical procedure permits dissection of the relative contribution of a given gene to OA initiation and/or progression. This chapter describes the requirements for the surgical induction of OA in mouse models, and provides guidelines and tools for the subsequent histological, immunohistochemical, and molecular analyses. Methods for the assessment of the contributions of selected genes in genetically modified strains are also provided.

11.
Gene ; 770: 145357, 2021 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-33333222

RESUMO

BACKGROUND: INAFM2 rs67839313 was associated with type 2 diabetes (T2DM) in Japanese populations but not in other populations. We aimed to validate the association of rs67839313 with T2DM and explore interactive associations of INAFM2 rs67839313 and egg consumption with T2DM and fasting blood glucose (FBG) in a Chinese population. METHODS: In total, 7175 participants (4202 T2DM cases) from 3980 families were included and categorized into two groups (<4 and ≥4 eggs/week) according to the median egg consumption. Multilevel logistic regression and linear regression models were performed to estimate the genetic associations of rs67839313 with T2DM and FBG, respectively. The crossproduct term between the variant and egg was included in the models for interaction analysis. RESULTS: We found that rs67839313_T was associated with an increased risk of T2DM (1.22 [95% CI: 1.17-1.27], P < 0.001). Among individuals with the rs67839313_T genotype, those with egg consumption <4/week (1.37 [1.25-1.51]) had a higher T2DM risk than those with egg consumption ≥4/week (1.17 [1.11-1.23]). A significant interactive effect between rs67839313_T and egg consumption on T2DM risk was identified (P = 0.008). Moreover, among participants without T2DM, rs67839313_T was associated with FBG, with a 0.188 mmol/l increase and a 0.152 mmol/l decrease among those consuming <4 eggs/week and ≥4 eggs/week, respectively. The interaction between rs67839313_T and egg consumption was observed to be significantly associated with FBG (P = 0.003). CONCLUSIONS: INAFM2 rs67839313_T was associated with increased T2DM risk and FBG levels in Chinese individuals, and consuming more eggs may eliminate the associated genetic risk. This finding has important implications for understanding the genetic pathogenesis of T2DM and for the precision nutrition management of T2DM.


Assuntos
Glicemia/metabolismo , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/genética , Ingestão de Alimentos , Ovos , Polimorfismo Genético , Idoso , Grupo com Ancestrais do Continente Asiático , China , Jejum , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
12.
Methods Mol Biol ; 2180: 427-436, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-32797425

RESUMO

Spermatozoa cryopreservation is used for the management of infertility and some other medical conditions. Routinely applied cryopreservation techniques depend on permeating cryoprotectants and relatively slow freezing rates. Cryoprotectant-free vitrification is an alternative and cost-effective method that is based on rapid cooling of spermatozoa by direct plunging into a cooling agent to prevent lethal intracellular ice crystallization and the detrimental effects of high salt concentrations. One of the problems with this technique is that full sterilization of commercially produced liquid nitrogen, which could be contaminated with different pathogens, is not possible. Here we use a benchtop device for the production of sterile liquid air with the same temperature as liquid nitrogen (-195.7 °C). This has been used to develop aseptic technology for cryoprotectant-free vitrification of human spermatozoa.

13.
Diabet Med ; : e14487, 2020 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-33278034

RESUMO

AIMS: To describe secular trends in diagnosed type 2 diabetes prevalence and incidence in Beijing, China. METHODS: Using health insurance claims for 17.7 million adults ≥ 20 years in 2008-2017, we identified people with diabetes using hospital diagnoses and drug prescriptions. Results were age-standardised using data for Beijing from China's 2010 census. Trends in prevalence and incidence were analysed using Joinpoint regression analysis. RESULTS: From 2008 to 2017 we identified 2,104,159 people diagnosed with type 2 diabetes. Type 2 diabetes prevalence increased from 3.7% [95%CI: (3.6,3.8)] to 6.6% (6.4,6.7), but the annual rate of increase slowed from 18.1% (14.4,22.0) to 1.5% (0.8,2.2) before and after 2011, respectively. Women had a higher diabetes prevalence than men, for all years. The yearly increase in prevalence was greater in people younger than 40 years, with an average annual percentage change of 13.6% (10.7,16.5) compared to 6.5% (5.6,7.4) in those over 40 years. Over the 10 years, the overall incidence decreased from 24.3 (24.2,24.4) to 11.5 (11.5,11.6) per 1000 person-years, but it increased in people younger than 40 years. The average age at diabetes diagnosis dropped from 62 to 56 years (P<0.001). Among incident cases of diabetes, the percentage of people under 40 years increased from 3.0% to 10.9% (P<0.001). CONCLUSIONS: The prevalence of diagnosed type 2 diabetes in Beijing increased continuously over the 10 years, the incidence decreased, except in people under 40 years. Continuous efforts are needed to prevent diabetes in China.

14.
Artigo em Inglês | MEDLINE | ID: mdl-33375320

RESUMO

BACKGROUND: Carotid intima-media thickness (cIMT) has been associated with an elevated risk of ischemic stroke (IS) in several studies, but the results are inconsistent. We investigated whether the association between cIMT and IS varied across different IS subtypes, and further assessed gene-cIMT interactions' association with IS risk. METHODS: A total of 1048 IS cases (795 large-artery atherosclerosis (LAA) cases, 103 small-vessel occlusion (SVO) cases, and 150 other subtypes) and 2696 IS-free controls across 2179 families were included in the analysis. Self-reported IS cases were confirmed through medical records' review and head imaging by computed tomography and/or magnetic resonance imaging. The mean values of the common cIMT obtained in bilateral distal and proximal carotid artery segments were used. The genotype information of rs2910164 polymorphism in microRNA-146a (miR-146a) was also collected. RESULTS: We found that cIMT was significantly associated with a higher risk of IS and LAA subtype but not SVO subtype in the multivariate-adjusted models. The odds ratio (OR) and 95% confidence interval (CI) in the highest quartile versus the lowest quartile of cIMT was 2.48 (1.92-3.20) for IS and 2.75 (2.08-3.64) for LAA (both p trend <0.001). The results also showed that there was a significant interaction between cIMT and rs2910164 genotype with the risk of IS (p interaction = 0.03) and LAA (p interaction = 0.02). The associations of cIMT with IS and LAA were strengthened among participants carried rs2910164_GG genotype compared with those with rs2910164_CC genotype. CONCLUSIONS: Our results indicate that higher cIMT levels were significantly associated with IS and LAA subtype but not SVO subtype, and the relations were modified by rs2910164 polymorphism in miR-146a.

16.
Artigo em Inglês | MEDLINE | ID: mdl-33051670

RESUMO

CONTEXT: Dietary fiber intake may relate to bone health. OBJECTIVE: To investigate whether dietary fiber intake is associated with bone mineral density (BMD), and the modification effect of genetic variations related to gut microbiota-derived short-chain fatty acids (SCFAs). DESIGN: The associations of dietary fiber intake with estimated BMD derived from heel ultrasound and fractures were assessed in 224,630 and 384,134 participants from UK Biobank. SETTING: UK Biobank. MAIN OUTCOME MEASURES: Estimated BMD derived from heel ultrasound. RESULTS: Higher dietary fiber intake (per standard deviation) was significantly associated with higher heel-BMD (ß [SE]=0.0047 [0.0003], P=1.10E-54). Similarly significant associations were observed for all the fiber subtypes including cereal, fruit (dried and raw), and vegetable (cooked and raw). (all P<0.05). The positive association was found in both women and men but more marked among men except for dietary fiber in cooked vegetables (All Pinteraction<0.05). A protective association was found between dietary fiber intake and hip fracture (HR, 95% CI: 0.94, 0.89-0.99; P=3.0E-02). In addition, the association between dietary fiber and heel-BMD was modified by genetically determined SCFA propionate production (Pinteraction=5.1E-03). The protective association between dietary fiber and heel-BMD was more pronounced among participants with lower genetically determined propionate production. CONCLUSIONS: Our results indicate that greater intakes of total dietary fiber and subtypes from various food sources are associated with higher heel-BMD. Participants with lower genetically determined propionate production may benefit more from taking more dietary fiber.

17.
Toxicon ; 188: 127-133, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33080268

RESUMO

T-2 toxin is a mycotoxin demonstrating several harmful effects on chondrocyte and cartilage functions. In the present study, we investigated the toxic effects of T-2 toxin on cartilage matrix degradation and evaluated the involvement of α2 integrin in T-2 toxin-induced matrix damage. In C28/I2 cells, T-2 toxin decreased cell viability in a dose-dependent manner. Regarding matrix degradation, T-2 toxin decreased type II collagen and increased matrix metalloproteinase 13 (MMP-13) expression. Moreover, T-2 toxin significantly decreased the expression of α2 integrin in C28/I2 cells, indicating impaired chondrocyte-matrix interaction. Additionally, cartilage matrix degradation with decreased type II collagen expression was observed in the animal model, established using rats treated with T-2 toxin, with or without a selenium-deficient diet, presenting chondrocytes with necrosis in the deep zone. Simultaneously, rats administered T-2 toxin demonstrated overtly decreased α2 integrin expression in the articular cartilage. In the T-2 toxin plus selenium-deficient diet group, α2 integrin expression was further decreased in the deep zone of the cartilage. Furthermore, inhibition of α2ß1 integrin in C28/I2 cells could induce MMP-13 activation and type II collagen reduction, contributing to matrix degradation. These results indicate that the cytotoxic effects of T-2 toxin on chondrocyte damage and cartilage matrix degradation are associated with α2 integrin downregulation, by reducing type II collagen and MMP-13 activation.


Assuntos
Cartilagem Articular/metabolismo , Integrina alfa2/metabolismo , Toxina T-2/toxicidade , Animais , Condrócitos , Colágeno Tipo II/metabolismo , Modelos Animais de Doenças , Metaloproteinase 13 da Matriz , Ratos
18.
Front Microbiol ; 11: 559728, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33013792

RESUMO

Microbes form close associations with host plants including rice as both surface (epiphytes) and internal (endophytes) inhabitants. Yet despite rice being one of the most important cereal crops agriculturally and economically, knowledge of its microbiome, particularly core inhabitants and any functional properties bestowed is limited. In this study, the microbiome in rice seedlings derived directly from seeds was identified, characterized and compared to the microbiome of the seed. Rice seeds were sourced from two different locations in Arkansas, USA of two different rice genotypes (Katy, M202) from two different harvest years (2013, 2014). Seeds were planted in sterile media and bacterial as well as fungal communities were identified through 16S and ITS sequencing, respectively, for four seedling compartments (root surface, root endosphere, shoot surface, shoot endosphere). Overall, 966 bacterial and 280 fungal ASVs were found in seedlings. Greater abundance and diversity were detected for the microbiome associated with roots compared to shoots and with more epiphytes than endophytes. The seedling compartments were the driving factor for microbial community composition rather than other factors such as rice genotype, location and harvest year. Comparison with datasets from seeds revealed that 91 (out of 296) bacterial and 11 (out of 341) fungal ASVs were shared with seedlings with the majority being retained within root tissues. Core bacterial and fungal microbiome shared across seedling samples were identified. Core bacteria genera identified in this study such as Rhizobium, Pantoea, Sphingomonas, and Paenibacillus have been reported as plant growth promoting bacteria while core fungi such as Pleosporales, Alternaria and Occultifur have potential as biocontrol agents.

19.
Genet Epidemiol ; 44(8): 811-824, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32869348

RESUMO

Gene-gene interaction (G × G) is thought to fill the gap between the estimated heritability of complex diseases and the limited genetic proportion explained by identified single-nucleotide polymorphisms. The current tools for exploring G × G were often developed for case-control designs with less considerations for their applications in families. Family-based studies are robust against bias led from population stratification in genetic studies and helpful in understanding G × G. We proposed a new algorithm epistasis sparse factor analysis (EPISFA) and epistasis sparse factor analysis for linkage disequilibrium (EPISFA-LD) based on unsupervised machine learning to screen G × G. Extensive simulations were performed to compare EPISFA/EPISFA-LD with a classical family-based algorithm FAM-MDR (family-based multifactor dimensionality reduction). The results showed that EPISFA/EPISFA-LD is a tool of both high power and computational efficiency that could be applied in family designs and is applicable within high-dimensionality datasets. Finally, we applied EPISFA/EPISFA-LD to a real dataset drawn from the Fangshan/family-based Ischemic Stroke Study in China. Five pairs of G × G were discovered by EPISFA/EPISFA-LD, including three pairs verified by other algorithms (FAM-MDR and logistic), and an additional two pairs uniquely identified by EPISFA/EPISFA-LD only. The results from EPISFA might offer new insights for understanding the genetic etiology of complex diseases. EPISFA/EPISFA-LD was implemented in R. All relevant source code as well as simulated data could be freely downloaded from https://github.com/doublexism/episfa.

20.
Soft Matter ; 16(37): 8547-8553, 2020 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-32909579

RESUMO

The time-resolved dynamic assembly and the structures of protein liquid dense clusters (LDCs) were analyzed under pulsed electric fields (EFs) applying complementary polarized and depolarized dynamic light scattering (DLS/DDLS), optical microscopy, and transmission electron microscopy (TEM). We discovered that pulsed EFs substantially affected overall morphologies and spatial distributions of protein LDCs and microcrystals, and affected the phase diagrams of LDC formation, including enabling protein solutions to overcome the diffusive flux energy barrier to phase separate. Data obtained from DLS/DDLS and TEM showed that LDCs appeared as precursors of protein crystal nuclei, followed by the formation of ordered structures within LDCs applying a pulsed EF. Experimental results of circular dichroism spectroscopy provided evidence that the protein secondary structure content is changing under EFs, which may consequently modulate protein-protein interactions, and the morphology, dimensions, and internal structure of LDCs. Data and results obtained unveil options to modulate the phase diagram of crystallization, and physical morphologies of protein LDCs and microcrystals by irradiating sample suspensions with pulsed EFs.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA