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1.
Dr. Patrick R. Cammarata Lawrence Oakford David Cantu-Crouch Robert Wordinger 《Cell and tissue research》1987,250(3):633-640
Summary The bovine lens capsule has previously been shown to provide an optimal surface for the examination of epithelial cell interaction with a basement membrane. This native substrate has been used to investigate some initial aspects of attachment of mouse blastocysts and trophoblastic cellular outgrowth. Mouse blastocysts were presented to the cell-free humoral side of the anterior lens capsule, incubated for 72 h, and examined by scanning and transmission electron microscopy. Blastocysts hatch and attach from their zonae pellucidae by 30 h. Trophoblastic cells proliferate rapidly in a coronal direction, display extensive surface microvilli, and advance by the extension of numerous filipodia, many of which terminate with bulbous projections. These projections were shown by transmission electron microscopy to contain numerous vacuoles and polysomes. To simulate further the initial blastocyst-uterine interaction, a suspension of lens epithelial cells was introduced to the capsule and permitted to form a monolayer prior to the addition of the blastocysts. At 72 h the monolayer of lens cells remained intact. We observed that: a) lens cells appear to recede from the advancing trophoblastic cells, and b) trophoblastic cells extend beneath the monolayer of lens cells and thereby dislodge the cells from the lens capsule substrate. No infiltration of the capsule by the advancing trophoblastic cells was observed. The lens capsule appears to offer a promising system for the study of trophoblast-epithelial cell interaction on a natural basement membrane. 相似文献
2.
G. Pellegrino D. Caimi M. E. Noce A. Musacchio 《Plant Systematics and Evolution》2005,251(2-4):119-129
The rewardless orchid Dactylorhiza sambucina shows a stable flower colour polymorphism, with both yellow- and red-flowered morphs growing sympatrically. Pollination biology and breeding system were investigated to examine the effects of density of plants, colour polymorphism, inflorescence dimension, and flower position within inflorescence on male and female reproductive success in three natural populations of D. sambucina. There were significant differences among sites in the number of pollinia removed and in fruit set per inflorescence. Number of removed pollinia and capsule production in D. sambucina were independent from flower and inflorescence size or flower position. As a whole, the red morphs showed the highest number of capsules produced, while the yellow morphs had the greatest male success. The relative male and female reproductive success were independent from plant density but were significantly correlated with the yellow morph frequency at the population level. Overall, our findings show that the contribution to the total reproductive success deriving from the two colour morphs does not conform with the predictions of negative frequency-dependent selection. 相似文献
3.
摘要 目的:探讨益肾活血汤联合百令胶囊对慢性肾功能衰竭患者肾功能、钙磷代谢和T淋巴细胞亚群的影响。方法:选取2020年5月~2022年3月期间上海中医药大学附属曙光医院收治的102例慢性肾功能衰竭患者,按随机数字表法分为对照组(常规西医治疗)和观察组(常规西医治疗联合益肾活血汤和百令胶囊治疗),各51例。两组均治疗8周。对比两组疗效及治疗前、治疗8周后中医证候积分、肾功能、钙磷代谢和T淋巴细胞亚群的变化。结果:观察组治疗8周后的临床总有效率为92.16%(47/51),高于对照组的74.51%(38/51)(P<0.05)。治疗8周后,两组中医主证积分、次证积分均较治疗前下降,且相比于对照组,观察组更低(P<0.05)。治疗8周后,血肌酐、尿素氮、24 h尿蛋白在两组中均较治疗前下降,且观察组低于对照组(P<0.05)。治疗8周后,两组CD8+较治疗前下降,且观察组低于对照组(P<0.05),而CD4+、CD3+、CD4+/CD8+均较治疗前升高,且观察组高于对照组(P<0.05)。治疗8周后,两组血磷、钙磷乘积下降,且观察组低于对照组(P<0.05),血钙均升高,且观察组高于对照组(P<0.05)。结论:益肾活血汤联合百令胶囊治疗慢性肾功能衰竭患者,可提高肾功能,改善钙磷代谢和T淋巴细胞亚群,并缓解其临床症状,疗效确切,值得临床借鉴应用。 相似文献
4.
摘要 目的:回顾性分析百令胶囊对糖尿病肾病患者机体微炎症状态、肾功能的影响。方法:2021年1月~2022年9月,回顾性收集120例糖尿病肾病患者临床资料,根据治疗方法分为降糖降脂组(56例)和百令胶囊组(64例)。降糖降脂组采用二甲双胍片、瑞舒伐他汀钙片进行治疗,百令胶囊组在降糖降脂组的基础上采用百令胶囊进行治疗。比较两组治疗3个月后疗效及治疗前、治疗3个月后糖脂代谢指标、微炎症状态及肾功能。结果:百令胶囊组治疗3个月后总有效率高于降糖降脂组(P<0.05)。治疗3个月后两组血清空腹血糖(FBG)、糖化血红蛋白(HbA1c)、总胆固醇(TC)、甘油三酯(TG)、白介素-6(IL-6)、超敏-C反应蛋白(hs-CRP)、血肌酐(SCr)、尿素氮(BUN)水平及24 h尿白蛋白(24 h UTP)、尿白蛋白排泄率(UAER)与治疗前比较,降低,百令胶囊组低于降糖降脂组(P<0.05);两组血清白介素-10(IL-10)水平与治疗前比较,升高,百令胶囊组高于降糖降脂组(P<0.05)。结论:百令胶囊可有效改善糖尿病肾病患者糖脂代谢、肾功能及微炎症状态,疗效较好。 相似文献
5.
Simultaneous production of xylanase and pectinase by Bacillus pumilus AJK under submerged fermentation was investigated in this study. Under optimized conditions, it produced 315?±?16 IU/mL acidic xylanase, 290?±?20 IU/mL alkaline xylanase, and 88?±?9 IU/mL pectinase. The production of xylano-pectinolytic enzymes was the highest after inoculating media (containing 2% each of wheat bran and Citrus limetta peel, 0.5% peptone, 10?mM MgSO4, pH 7.0) with 2% of 21-hr-old culture and incubated at 37°C for 60?hr at 200?rpm. Xylanase retained 100% activity from pH 6.0 to10.0 after 3?hr of incubation, while pectinase showed 100% stability from pH 6.0 to 9.0 even after 6?hr of incubation. Cost-effective and concurrent production of xylanase and pectinase by a bacterial isolate in the same production media suggests its potential for various biotechnological applications. This is the first report of simultaneous production of industrially important extracellular xylano-pectinolytic enzymes by B. pumilus. 相似文献
6.
The formation of titan cells in Cryptococcus neoformans depends on the mouse strain and correlates with induction of Th2‐type responses 下载免费PDF全文
Irene García‐Barbazán Nuria Trevijano‐Contador Cristina Rueda Belén de Andrés Raquel Pérez‐Tavárez Inés Herrero‐Fernández María Luisa Gaspar Oscar Zaragoza 《Cellular microbiology》2016,18(1):111-124
Cryptococcus neoformans is a pathogenic yeast that can form titan cells in the lungs, which are fungal cells of abnormal enlarged size. Little is known about the factors that trigger titan cells. In particular, it is not known how the host environment influences this transition. In this work, we describe the formation of titan cells in two mouse strains, CD1 and C57BL/6J. We found that the proportion of C. neoformans titan cells was significantly higher in C57BL/6J mice than in CD1. This higher proportion of titan cells was associated with a higher dissemination of the yeasts to the brain. Histology sections demonstrated eosinophilia in infected animals, although it was significantly lower in the CD1 mice which presented infiltration of lymphocytes. Both mouse strains presented infiltration of granulocytes, but the amount of eosinophils was higher in C57BL/6J. CD1 mice showed a significant accumulation of IFN‐γ, TNF‐α and IL17, while C57BL/BL mice had an increase in the anti‐inflammatory cytokine IL‐4. IgM antibodies to the polysaccharide capsule and total IgE were more abundant in the sera from C57BL/6J, confirming that these animals present a Th2‐type response. We conclude that titan cell formation in C. neoformans depends, not only on microbe factors, but also on the host environment. 相似文献
7.
Effects of high temperature coupled with high light on the balance between photooxidation and photoprotection in the sun-exposed peel of apple 总被引:4,自引:1,他引:4
The sun-exposed peel of 'Gala' apple with or without sunburn was compared in terms of photooxidation and photoprotection, and a controlled experiment was conducted to probe the initial responses of PSII to high light and high temperature. The content of carotenoids, lutein and xanthophylls on a chlorophyll basis was higher in the sunburned peel although they were lower expressed on a peel area basis. Significant loss of beta-carotene and neoxanthin was observed relative to chlorophylls in the sunburned peel. O(2) evolution rates and the activity of key enzymes in the Calvin cycle were lower in the sunburned peel, but the activity of these enzymes decreased to a lesser extent than the O(2) evolution rates. The activity of antioxidant enzymes in the ascorbate-glutathione cycle and the level of total ascorbate, total glutathione, and reduced glutathione were higher in the sunburned peel. However, the sunburned peel had higher H(2)O(2) and malondialdehyde contents. Fruit peels treated with high temperature (45 degrees C) alone showed a clear "K" step in their chlorophyll fluorescence transients whereas high temperature coupled with high light (1,600 mumol m(-2) s(-1)) led to the disappearance of the "K" step and a further decrease in F (V)/F (M) (similar to what was observed in the sunburned peel). We conclude that high temperature coupled with high light damages the PSII complexes at both the donor and acceptor sides. Although both the xanthophyll cycle and the antioxidant system are up-regulated in response to the photooxidative stress, this up-regulation does not provide enough protection against the photooxidation. 相似文献
8.
Mark D. Gonzalez Carol A. Lichtensteiger Eric R. Vimr 《FEMS microbiology letters》2001,198(2):125-128
With the exception of the polysialic acid capsule (K1 antigen), little is known about other virulence factors needed for systemic infection by Escherichia coli K1, the leading cause of Gram-negative neonatal meningitis in humans. In this work, the functional genomics method of signature-tagged mutagenesis (STM) was adapted to E. coli K1 and the infant-rat model to identify non-capsule virulence genes. Validation of the method was demonstrated by the failure to recover a reconstructed acapsular mutant from bacterial pools used to systemically infect 5-day-old rats. Three new genes required for systemic disease were identified from a total of 192 mutants screened by STM (1.56% hit rate). Gut colonization, Southern blot hybridization, mixed-challenge infection, and DNA sequence analyses showed that the attenuating defects in the mutants were associated with transposon insertions in rfaL (O antigen ligase), dsbA (thiol:disulfide oxidoreductase), and a new gene, puvA (previously unidentified virulence gene A), with no known homologues. The results indicate the ability of STM to identify novel systemic virulence factors in E. coli K1. 相似文献
9.
10.
《Saudi Journal of Biological Sciences》2022,29(10):103374
The liver is more prone to infections that cause fibrosis, such as steatosis, non-alcoholic steatohepatitis, hepatotoxicity, cirrhosis, and hepatocellular carcinoma. Also, Viral hepatitis is a common condition worldwide it worsens into chronic inflammation of the liver. One of the healthiest fruits is the pomegranate for the body and health, as it contains a high nutritional value of minerals, vitamins, antioxidants, so we worked on this investigation to magnify the therapeutic applications of pomegranate fruits (POF) and peel (POP) in carbon tetrachloride-injected rats (Ccl4). The experiment was carried out in a caged animal. All rats were fed a basal diet for one week before the study, and they were divided into seven groups, each with six rats. As a control negative group (C–ve), the first group sample was fed only the basal diet for 28 days. The remaining rats (n = 36) were injected with carbon tetrachloride (Ccl4). Five groups were fed varying concentrations of (5 %, 10 %, 15 % POF, 5 %, and 10 % pomegranate peel (POP)), whereas one group was diagnosed with the illness and disease, and didn't even feed the experimental diet. The results revealed significant increases in T.BIL, D.BIL, and BIL in the serum of rats injected by CC14 to induce hepatopathy compared to the healthy group (normal rats). Also, the best treatment considering the serum D.BIL was recorded for the 5 % POF. 相似文献