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101.

Aim

Neuropathy and neuropathic pain are common complications of type 1 diabetes (T1D). We aimed to determine if sex-specific differences in neuropathic pain are present in adults with longstanding T1D.

Methods

Canadians with ≥50?years of T1D (n?=?361) completed health history questionnaires that included assessment of neuropathy (defined by Michigan Neuropathy Screening Instrument questionnaire components ≥3; NEUROPATHYMNSI-Q) and neuropathic pain. Multivariable logistic regression was used to determine sex-differences in neuropathic pain controlling for neuropathy.

Results

Participants had mean age 66?±?9?years, median diabetes duration 53[51,58] years, mean HbA1c 7.5?±?1.0%, and 207(57%) were female. Neuropathic pain was present in 128(36%) of all participants, more prevalent among those with NEUROPATHYMNSI-Q compared to those without [96(63%) vs. 31(15%), p?<?0.001], and more prevalent in females compared to males [87(42%) vs. 41(27%), p?=?0.003]. Independent of the presence of NEUROPATHYMNSI-Q and other factors, female sex was associated with the presence of neuropathic pain [OR 2.68 (95% CI 1.4–5.0), p?=?0.002].

Conclusions

We demonstrated a novel sex-specific difference in neuropathic pain in females compared to males with longstanding T1D, independent of the presence of neuropathy. Further research using more objective measures of neuropathy than the MNSI is justified to further understand this sex-specific difference.  相似文献   
102.
Dynamics of tyrosine hydroxylase (TH) was studied in various brain regions and pituitary in relation to annual/seasonal and circadian variations in either sex of the catfish Heteropneustes fossilis. alpha-Methylparatyrosine inhibited TH activity significantly in a time-(in vivo study) and concentration-(in vitro study) dependent manner. The inhibition was higher in resting phase than preparatory phase and in females than males (time-course study). The apparent kinetic constant of inhibition (K(i)) varied both seasonally and regionally. The values were higher in resting phase and in the forebrain regions (telencephalon and hypothalamus) than medulla oblongata. No significant sex difference was noticed in the K(i) values in the same season. TH activity showed significant annual/seasonal variations with telencephalon and hypothalamus showing higher activity than medulla oblongata. The females showed significantly higher enzyme activity than males with a distinct activity peak in June (prespawning phase). Such an activity peak was apparently absent in males. TH activity showed significant circadian/diurnal variations, the highest activity was noticed at 12 h and the lowest at 24 h. The apparent Michaelis-Menten constant (K(m)) values (hypothalamic TH) for substrate (L-tyrosine) and cofactor (DMPH(4)) showed seasonal variations with the highest values in the resting phase, decreasing through preparatory and prespawning phases, to the lowest values in spawning phase. V(max) was the lowest in the resting phase and highest in the spawning phase. TH activity was low in the pituitary and could be detected in pooled samples from March (preparatory phase) to July (spawning phase). Activity showed significant variations, which could be correlated with the gonadosomatic index. The results show that TH activity could be positively correlated with the annual reproductive cycle. The enzyme activity could be also correlated with seasonal, sex, and regional variations in the apparent K(m) and V(max) values suggesting apparent differences in the affinity of the enzyme towards substrate and cofactor.  相似文献   
103.
104.
目的了解德宏州2005-2012年间看守所羁押人员的HIV感染况及影响因素。方法对当地看守所羁押人员进行问卷调查,并采集血样检测艾滋病病毒(HIV)抗体。结果 19 859名调查对象中,83.3%为男性,其中汉族、农民占60%以上;女性中汉族、农民占50%以上。调查对象HIV抗体阳性检出率为3.7%(736人),64.3%(473/736)为入所后新报告者。Logistic多因素分析显示,男性中,≥20岁、少数民族、文盲及外籍者HIV抗体阳性检出率较高,注射吸毒者[比值比(OR)=11.25,95%可信区间(CI):9.36-13.53]及与非固定性伴发生性行为者(OR=2.46,95%CI:2.03-2.97)HIV感染风险高;女性中,≥20岁、除景颇族外的少数民族、外籍者HIV抗体阳性检出率较高,注射吸毒者(OR=11.17,95%CI:6.73-18.54)和与非固定性伴发生性行为者(OR=2.54,95%CI:1.40-3.97)感染HIV风险高。结论德宏州看守所羁押人员HIV感染率较高,且多数为新检测发现者,提示有必要继续加强对监管场所人员开展HIV监测及干预工作,减少艾滋病蔓延。  相似文献   
105.
目的 观察新诊断糖尿病成年男性患者性激素结合球蛋白(SHBG)的变化,探讨其与IR及胰岛早相分泌功能的关系. 方法 纳入新诊断糖尿病男性患者56例为糖尿病组,另选健康成年男性38名为正常对照组,测定SHBG,进行精氨酸刺激试验. 结果 两组SHBG、胰岛素抵抗指数(HOMA-IR)差异有统计学意义(P<0.01).相关分析显示,SHBG与HOMA-IR呈负相关(r=-0.219,P<0.05).Logistic回归分析显示,SHBG是IR的唯一有效自变量(β=-0.75,P<0.05,OR=0.47).二元Logistic回归分析得出HOMA-IR是糖尿病的危险因素,SHBG是糖尿病的保护因素.胰岛2 min分泌高峰值与HOMA-IR呈正相关(β=0.567,P<0.05). 结论 新诊断糖尿病成年男性患者存在血清SHBG降低,SHBG与HOMA-IR呈负相关.SHBG是新诊断糖尿病成年男性患者的独立保护因素.胰岛β细胞第一时相分泌功能减退与IR相关,与SHBG无相关性.  相似文献   
106.
107.
Environmental enrichment (EE), comprising positive physical (exercise) and cognitive stimuli, influences neuronal structure and usually improves brain function. The promise of EE as a preventative strategy against neuropsychiatric disease is especially high during early postnatal development when the brain is still amenable to reorganization. Despite the fact that male and female brains differ in terms of connectivity and function that may reflect early life experiences, knowledge of the neural substrates and mechanisms by which such changes arise remains limited. This study compared the impact of EE combined with physical activity on neuroplasticity and its functional consequences in adult male and female rats; EE was provided during the first 3 months of life and our analysis focused on the hippocampus, an area implicated in cognitive behavior as well as the neuroendocrine response to stress. Both male and female rats reared in EE displayed better object recognition memory than their control counterparts. Interestingly, sex differences were revealed in the effects of EE on time spent exploring the objects during this test. Independently of sex, EE increased hippocampal turnover rates of dopamine and serotonin and reduced expression of 5-HT1A receptors; in addition, EE upregulated expression of synaptophysin, a presynaptic protein, in the hippocampus. As compared to their respective controls, EE-exposed males exhibited parallel increases in phosphorylated Tau and the GluN2B receptor, whereas females responded to EE with reduced hippocampal levels of glutamate and GluN2B. Together, these observations provide further evidence on the differential effects of EE on markers of hippocampal neuroplasticity in males and females.  相似文献   
108.
109.
肝脏是调节体内脂类代谢最重要的器官之一。肝脂肪变性是代谢综合征的主要表现,与脂类物质合成和分解之间的不平衡有关。脂肪肝的患病率存在性别和年龄差异,提示性激素在其中起着至关重要的作用。本文总结了目前有关雌激素和雄激素通过雌激素受体和雄激素受体来调控肝脏脂类代谢机制的文献。于雌性而言,雌二醇与雌激素受体结合降低肝脏脂肪生成及脂肪酸摄取,同时增强脂肪分解和胆固醇分泌。在雄性体内,睾丸激素通过雄激素受体减少脂肪生成并促进脂肪分解。这些研究结果表明,性激素及其受体可以作为预防肝脂肪变性的潜在靶标。  相似文献   
110.
Autoimmune diseases are a range of diseases in which the immune response to self-antigens results in damage or dysfunction of tissues. Autoimmune diseases can be systemic or can affect specific organs or body systems. For most autoimmune diseases there is a clear sex difference in prevalence, whereby females are generally more frequently affected than males. In this review, we consider gender differences in systemic and organ-specific autoimmune diseases, and we summarize human data that outlines the prevalence of common autoimmune diseases specific to adult males and females in countries commonly surveyed. We discuss possible mechanisms for sex specific differences including gender differences in immune response and organ vulnerability, reproductive capacity including pregnancy, sex hormones, genetic predisposition, parental inheritance, and epigenetics. Evidence demonstrates that gender has a significant influence on the development of autoimmune disease. Thus, considerations of gender should be at the forefront of all studies that attempt to define mechanisms that underpin autoimmune disease.  相似文献   
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