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91.
E. Stephen Buescher Sarah M. McIlheran Steven M. Banks Andrezej P. Kudelka John J. Kavanagh Saroj Vadhan-Raj 《Cancer immunology, immunotherapy : CII》1993,37(1):26-30
During a phase I trial of interleukin-1 (IL-1) in patients with ovarian carcinomas, the effects of this treatment on blood granulocyte respiratory burst and locomotive responses were examined. Differences in baseline granulocyte function in patients as well as dose-related effects of IL-1 treatment were observed. Patients enrolled early in the trial (low-dose patients) had significantly lower locomotive responses before treatment than their paired controls; these low responses normalized after 5 days of continuous-infusion IL-1 treatment. Patients enrolled later (high-dose patients) had normal locomotive responses before treatment and IL-1 treatment was associated with suppression of responses to selected stimuli at the end of treatment. Pretreatment respiratory burst responses in both low-and high-dose patient groups were essentially normal, but the rates of granulocyte H2O2 production following phorbol myristate acetate stimulation became significantly less than control values at the end of treatment. In vitro exposure of either patient or control cells to 150 U/ml IL-1 did not alter their locomotive or respiratory burst responses, suggesting the observed in vivo effects were not mediated directly by IL-1. Treatment with IL-1 is associated with changes in ex vivo granulocyte function that are related to the IL-1 dose. Treatment with low doses of IL-1 may provide a means of normalizing abnormal polymorphonuclear leukocyte function in some patients with ovarian malignancies. 相似文献
92.
93.
Haoran Xu Shuai Chen Xue Song Jingying Wang 《Molecular & cellular biomechanics : MCB》2023,20(1):15-22
Clinically, it is common for Class III patients with maxillary skeletal deficiency, which may result in a variety of
adverse consequences. Protraction headgear and rapid maxillary expansion (PE) is an effective treatment, but its
effect on upper airway hydrodynamics has not been reported. The main purpose of this study was to evaluate the
changes of the flow in the upper airway after PE by computational fluid dynamics (CFD). The sample includes
fifteen patients (6 males, 9 females, age 11.00 ± 1.00) and the paired T-test was used to analyze the differences
between the measured data before and after treatment. The maximum flow velocity decreased from 8.42 ±
0.16 m/s to 6.98 ± 0.36 m/s (p < 0.05), and the maximum shear force decreased from 3.72 ± 1.48 Pa to 2.13 ±
0.18 Pa. The maximum negative pressure decreased from −101.78 ± 33.60 Pa to 58.15 ± 9.16 Pa, only the changes
of velopharynx and glossopharynx were statistically significant; while the maximum resistance decreased from
140.88 ± 68.68 Pa/mL/s to 45.95 ± 22.96 Pa/mL/s. PE can effectively reduce the airflow resistance of the upper
airway and the probability of airway collapse, thus improving the patient’s ventilation function. 相似文献
94.
95.
BackgroundPregnant women are among the key groups in iodine nutrition evaluation. The purpose of the present study was to summarize the evidence supporting the relationship between mild iodine deficiency (UIC: 100–150 μg/L) in pregnant women and levels of thyroid function tests.MethodsThis review follows the guidelines for systematic reviews (PRISMA 2020). Three electronic databases (PubMed, Medline, and Embase) were searched for relevant publications in English on the association between mild iodine deficiency in pregnant women and thyroid function. Articles published in Chinese were searched in China’s electronic databases (CNKI, WanFang, CBM, and WeiPu). Pooled effects were presented as standardized mean differences (SMDs) and odds ratios (ORs) with 95% confidence intervals (CIs) using fixed or random effect models, respectively. This meta-analysis was registered at www.crd.york.ac.uk/prospero as CRD42019128120.ResultsWe summarized the results from 7 articles with 8261 participants. The overall pooled results showed that the levels of FT3, FT4, and abnormal TgAb (the antibody levels exceeded the upper limit of the reference range) were significantly increased in pregnant women with mild iodine deficiency compared to pregnant women with adequate iodine status (FT3: SMD=0.854, 95% CI: 0.188, 1.520; FT4: SMD=0.550, 95% CI: 0.050, 1.051; TgAb: OR=1.292, 95% CI: 1.095; 1.524). Subgroup analysis was carried out on the sample size, ethnicity, country, and gestation of FT3, FT4, and TSH, but no plausible factor was found. Egger’s tests indicated no publication bias.The increase in FT3 and FT4, as well as TgAb levels, in pregnant women is associated with mild iodine deficiency.ConclusionMild iodine deficiency is associated with an increase in FT3,FT4 and TgAb levels in pregnant women. Mild iodine deficiency may increase the risk of thyroid dysfunction in pregnant women. 相似文献
96.
Iron deficiency is a common micronutrient deficiency associated with metabolic changes in the levels of iron regulatory proteins, hepcidin and ferroportin. Studies have associated dysregulation of iron homeostasis to other secondary and life-threatening diseases including anaemia, neurodegeneration and metabolic diseases. Iron deficiency plays a critical role in epigenetic regulation by affecting the Fe2+/α-ketoglutarate-dependent demethylating enzymes, Ten Eleven Translocase 1–3 (TET 1–3) and Jumonji-C (JmjC) histone demethylase, which are involved in epigenetic erasure of the methylation marks on both DNA and histone tails, respectively. In this review, studies involving epigenetic effects of iron deficiency associated with dysregulation of TET 1–3 and JmjC histone demethylase enzyme activities on hepcidin/ferroportin axis are discussed. 相似文献
97.
ObjectivesZinc, which is found in high concentrations in the β-cells of the pancreas, is also a critical component for the endocrine functions of the pancreas. SLC30A8/ZnT8 is the carrier protein responsible for the transport of zinc from the cytoplasm to the insulin granules. The aim of this study was to investigate how dietary zinc status affects pancreatic beta cell activation and ZnT8 levels in infant male rats born to zinc-deficient mothers.MethodsThe study was performed on male pups born to mothers fed a zinc-deficient diet. A total of 40 male rats were divided into 4 equal groups. Group 1: In addition to maternal zinc deficiency, this group was fed a zinc-deficient diet. Group 2: In addition to maternal zinc deficiency, this group was fed a standard diet. Group 3: In addition to maternal zinc deficiency, this group was fed a standard diet and received additional zinc supplementation. Group 4: Control group. Pancreas ZnT8 levels were determined by ELISA method and insulin-positive cell ratios in β-cells by immunohistochemistry.ResultsThe highest pancreatic ZnT8 levels and anti-insulin positive cell ratios in the current study were obtained in Group 3 and Group 4. In our study, the lowest pancreatic ZnT8 levels were obtained in Group 1 and Group 2, and the lowest pancreatic anti-insulin positive cell ratios were obtained in Group 1.ConclusionThe results of the present study; in rats fed a zinc-deficient diet after maternal zinc deficiency has been established shows that ZnT8 levels and anti-insulin positive cell ratios in pancreatic tissue, which is significantly suppressed, reach control values with intraperitoneal zinc supplementation. 相似文献
98.
Luis A. Videla Loreto Correa Marcela Rivera Teresa Sir 《Free radical biology & medicine》1993,14(6):669-675
Luminol-amplified CL of whole blood phagocytes was studied in rats given 3 consecutive doses of 0.1 mg L-triiodothyronine T3/kg or in hyperthyroid patients, after stimulation by zymosan. In both cases, CL was significantly increased, in effect which was produced independently of the opsonization of the zymosan particles and markedly inhibited by azide. The in vitro addition of T3 or L-thyroxine (T4) to whole blood phagocytes from normal rats did not modify the opsonized zymosan-dependent CL, when assayed at the concentrations found in eutrhyroid subjects or in hyperthyroid patients. Administrations of propylthiouracil (400 mg/day for 2–3 months) to hyperthyroid patients reduced the CL response observed prior to treatment, to values comparable to those found in the euthyroid group. These data indicate that hyperthyroidism elicits an enhanced respiratory burst activity of whole blood phagocytes, probably related to adaptive changes induced by thyroid hormone on the mieloperoxidase-H2O2 system, rather than to direct actions of the hormone molecule or changes in the opsonic capacity of plasma. 相似文献
99.
《Revista espa?ola de geriatría y gerontología》2023,58(4):101381
Background and aimsSince the beginning of the COVID-19 pandemic, the elderly population has had the highest rates of complications and mortality. This study aimed to determine the influence of different risk factors on deaths due to the Omicron variant in the Canary Islands.Materials and methodsA retrospective observational study of 16,998 cases of COVID-19 over 40 years of age was conducted in the Canary Islands between August 1, 2022, and January 31, 2023. We extracted sociodemographic data (age and sex) and clinical data (death, vaccination history, hospital admission, previous diseases, and treatments).ResultsAmong the deaths, there was a higher proportion of males aged over 70 years, with diabetes, cardiovascular, renal, respiratory, and systemic diseases, and nursing home residents. Significant differences were observed in the number of doses of the vaccine. The multiple regression model showed that male sex (OR [95% CI] = 1.92 [1.42–2.58]), age (70–79 years, 9.11 [4.27–19.43]; 80–89 years, 21.72 [10.40–45.36]; 90–99 years, 66.24 [31.03–141.38]; 100 years or older, 69.22 [12.97–369.33]), being unvaccinated (6.96, [4.01–12.08]), or having the last dose administered at least 12 months before the diagnosis (2.38, [1.48–3.81]) were significantly associated with mortality.ConclusionsMultiple factors may increase the risk of mortality due to COVID-19 in the elderly population. In our study, we found that only three predictors can effectively explain the variability: older age, male sex, and not being vaccinated or last vaccination date prior to one year. 相似文献
100.
目的 利用果蝇作为遗传工具从个体和分子层面研究果蝇的训练免疫效应,并为后续深入研究其分子机制提供依据。方法 首先构建无菌果蝇模型,在此基础上构建果蝇成虫及跨发育阶段训练免疫模型,用两种革兰氏阴性菌——胡萝卜软腐欧文氏菌(Erwinia carotovora carotovora 15)及铜绿假单胞菌(Pseudomonas aeruginosa)分别经口腔感染果蝇。在第一次感染完全消退后进行再次感染,然后通过比较果蝇在两个感染阶段的存活率和细菌量来衡量训练免疫的潜在效果。通过实时荧光定量PCR检测相应先天免疫相关基因的表达水平,研究革兰氏阴性菌对免疫缺陷(IMD)通路的诱导作用。结果 果蝇成虫及幼虫初次感染均可提高二次感染后的生存率、细菌清除效率及死亡时能承受的最高细菌负荷;二次感染的果蝇中,IMD通路中免疫反应基因的基础表达比未感染的高,这提供了获得感染抗性的分子基础;果蝇的免疫反应主要发生在中肠,二次免疫比初次免疫的效应更迅速且剧烈;二次免疫的果蝇中,肠道干细胞的数量显著多于初次感染。结论 果蝇肠道中强大的训练免疫可由同源或异源革兰氏阴性菌口腔感染引发,且免疫记忆可在整个发育阶段持... 相似文献