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141.
Kankshi Sahu Anumegha Gupta Alka Sharma Meenakshi Tiwari Ashutosh N. Pandey Shilpa Prasad 《Growth factors (Chur, Switzerland)》2018,36(1-2):41-47
In mammals, preovulatory oocytes are encircled by several layers of granulosa cells (GCs) in follicular microenvironment. These follicular oocytes are arrested at diplotene arrest due to high level of cyclic nucleotides from encircling GCs. Pituitary gonadotropin acts at the level of encircling GCs and increases adenosine 3′,5′-cyclic monophosphate (cAMP) and guanosine 3′,5′-cyclic monophosphate (cGMP) and activates mitogen-activated protein kinase 3/1 (MAPK3/1) signaling pathway. The MAPK3/1 disrupts the gap junctions between encircling GCs and oocyte. The disruption of gap junctions interrupts the transfer of cyclic nucleotides to the oocyte that results a drop in intraoocyte cAMP level. A transient decrease in oocyte cAMP level triggers maturation promoting factor (MPF) destabilization. The destabilized MPF finally triggers meiotic resumption from diplotene arrest in follicular oocyte. Thus, MAPK3/1 from GCs origin plays important role in gonadotropin-mediated meiotic resumption from diplotene arrest in follicular oocyte of mammals. 相似文献
142.
D. H. Phalke S. R. Patil A. L. Pharande M. C. Manna Asha Sahu Shamandeep Kaur 《Proceedings of the National Academy of Sciences, India. Section B.》2016,86(2):299-307
An investigation was carried out by conducting a field experiment at the farm of the Mahatma Phule Krishi Vidyapeeth (MPKV), Rahuri. The significant grain yield of soybean (37.5 q ha?1) and maize (49 q ha?1) were observed in the treatment receiving 100 % recommended doses of Nitrogen, Phosphorus and Potassium (NPK) + in situ compost of crop residues, pressmud compost (T6). After harvest of maize dehydrogenase activity, acid phosphatase, β-glucosidase and urease were significantly improved in T7 treatment as compared to other treatments. However, fluorescein diacetate activity and alkaline phosphatase were significantly greater in T6 treatment in post-harvest soil samples of maize. In the post-harvest soil of maize the bacterial and actinomycetes population were greater in the treatment receiving in situ decomposition of sugarcane crop residues + 100 % recommended dose of NPK (T3). The fungal population after harvest of maize was found maximum in treatment T7. The total organic carbon was significantly correlated with dehydrogenase (r = 0.65, P < 0.01), fluorescein diacetate (r = 0.71, P < 0.01), acid phosphatase (r = 0.66, P < 0.01), β-glucosidase (r = 0.65, P < 0.01), and urease (r = 0.57, P < 0.01). There was a significant correlation (r = 0.77, P < 0.01) between TOC and soybean yield, and between total organic carbon and maize yield (r = 0.98, P < 0.01). The result suggest that in situ recycling of sugarcane crop residues and the industrial wastes with suitable interventions like use of bioinoculum, phosphatic fertilizer and urea may help for improving better crop productivity and soil biological activities. 相似文献
143.
改性羟基磷灰石骨修复纳米复合材料的制备及生物学评价 总被引:5,自引:7,他引:5
目的:制备羟基磷灰石/聚乳酸聚乙醇酸骨修复材料,并对其进行生物学评价。方法:实验于2006-06/2007-02在中科院长春应用化学研究所完成材料制备,在吉林大学基础医学院实验动物中心完成动物实验。将低聚乳酸的羧基与羟基磷灰石表面的钙原子用化学键连接,得到表面接枝聚左旋乳酸的羟基磷灰石,将其与聚乳酸聚乙醇酸共混,得到复合材料PLLA-g-HA/PLGA。溶于氯仿后铺膜(厚0.2mm),用DMEM培养液浸泡材料膜制备浸提液。首先,进行材料生物安全性实验:①细胞毒性实验:将浸提液与培养液混合,接种兔成骨细胞,培养24h,MTT法检测细胞增殖,计算细胞增殖率和细胞毒性级(细胞毒性级0或1级为合格)。②全身毒性实验:小鼠以50mL/kg的剂量静脉注射浸提液,观察72h内小鼠中毒症状。③皮肤刺激实验:兔脊柱两侧皮内注射材料浸提液,观察72h内皮肤有无异常反应。④热原实验:自兔耳缘静脉注入浸提液(10mL/kg)。注射后每0.5h测肛温1次,共6次,以6次中最高的1次减去正常体温,计为升高度数。其次,对复合材料进行细胞黏附性检测:将复合材料制成1%氯仿溶液,涂于硅化的盖玻片上,置于6孔板,每孔接种1×105个成骨细胞,培养3d,在2,24,72h行FITC荧光染色,数码摄像系统拍摄细胞荧光照片。结果:制备了新型PLLA-g-HA/PLGA复合材料。①生物安全性实验结果:MTT实验检测复合材料细胞增殖率为94.8%,细胞毒性级为1级;全身毒性实验中动物无死亡、惊厥、瘫痪、呼吸抑制、腹泻和体质量下降等不良反应;热原实验中兔体温最大的变化值是0.25℃(国家标准为<0.6℃);皮肤刺激实验中未见任何刺激反应,无红斑、焦痂、水肿表现。②细胞黏附性实验结果:细胞接种后2h可见少量细胞开始贴壁;24h时可见贴壁细胞明显增多,并呈聚集生长;培养3d后可见细胞逐渐融合,细胞状态良好。结论:新型PLLA-g-HA/PLGA复合材料符合生物材料细胞毒性要求,按毒性剂量分级属无毒级,无致热原性、对皮肤无刺激作用,具有良好的生物相容性和细胞黏附性。 相似文献
144.
Hope Caughron Dennis Kim Norihiko Kamioka Stamatios Lerakis Altayyeb Yousef Aneesha Maini Shawn Reginauld Anurag Sahu Subhadra Shashidharan Maan Jokhadar Fred H. Rodriguez Wendy M. Book Michael McConnell Peter C. Block Vasilis Babaliaros 《JACC: Cardiovascular Interventions》2018,11(24):2495-2503
Objectives
This study compares 30-day, 1-year, and 3-year echocardiographic findings and clinical outcomes of transcatheter pulmonary valve-in-valve replacement (TPVR) and repeat surgical pulmonary valve replacement (SPVR).Background
In patients with adult congenital heart disease and previous pulmonary valve replacement (PVR) who require redo PVR, it is unclear whether TPVR or repeat SPVR is the preferred strategy.Methods
We retrospectively identified 66 patients (TPVR, n = 36; SPVR, n = 30) with bioprosthetic pulmonary valves (PVs) who underwent either TPVR or repeat SPVR at Emory Healthcare from January 2007 to August 2017.Results
The TPVR cohort had fewer men and more patients with baseline New York Heart Association (NYHA) functional class III or IV. There was no difference in mortality, cardiovascular readmission, or post-procedural PV reintervention at 30 days, 1 year, or 3 years. Post-procedural echocardiographic findings showed no difference in mean PV gradients between the TPVR and SPVR groups at 30 days, 1 year, or 3 years. In the TPVR cohort, there was less right ventricular dysfunction at 30 days (2.9% vs. 46.7%; p < 0.01), despite higher baseline NYHA functional class in the SPVR cohort.Conclusions
In patients with bioprosthetic PV dysfunction who underwent either TPVR or SPVR, there was no difference in mortality, cardiovascular readmission, or repeat PV intervention at 30 days, 1 year, or 3 years. Additionally, TPVR and SPVR had similar intermediate-term PV longevity, with no difference in PV gradients or PVR. The TPVR cohort also had less right ventricular dysfunction at 30 days despite a higher baseline NYHA functional classification. These intermediate-term results suggest that TPVR may be an attractive alternative to SPVR in patients with previous bioprosthetic surgical PVs. 相似文献145.
Kamal Kant Sahu Pankaj Malhotra Alka Khadwal Manupdesh Singh Sachdeva Prashant Sharma Neelam Varma Subhash Chander Varma 《Indian journal of hematology & blood transfusion》2015,31(4):460-465
Eosinophilia is rare in acute leukemia at presentation. Discrete reports and case studies in recent years have created significant interest in the field of “Acute leukemia with eosinophilia”. We herein present two cases of eosinophilia in association with acute lymphoblastic leukemia with brief review of literature in this field. First case is about 21-year-old female who presented with mediastinal mass along with leukocytosis and hypereosinophilia. On evaluation, she was found to have T cell acute lymphoblastic leukemia. After ruling out benign causes of eosinophilia, she was treated with modified BFM-90 protocol. Her eosinophilia resolved after 4 weeks of induction therapy. Second case is about 32-year-old male who was diagnosed as a case of mixed phenotype leukemia (B cell/myeloid type) along with severe eosinophilia. His hypereosinophilia finally resolved by week 16 of modified BFM-90 protocol. Diagnosing ALL is challenging when eosinophilia is the initial presentation. These two cases emphasize on the importance of considering ALL amongst one of the etiological causes of eosinophilia as delay in diagnosis endangers patient’s life at risk. Also eosinophilia per se is an independent poor risk factor, hence prompt diagnosis and early treatment is the key in all such cases. 相似文献
146.
Kamal Kant Sahu Ruchita Tyagi Arjun Datt Law Alka Khadwal Gaurav Prakash Arvind Rajwanshi Subhash Chander Varma Pankaj Malhotra 《Indian journal of hematology & blood transfusion》2015,31(4):466-471
Myeloid sarcoma is an extramedullary tumor seen most commonly in patients with acute myeloid leukemia and less frequently in chronic myeloid leukemia, myelodysplastic syndrome and rarely, in an isolated form without any other underlying malignancy. Malignant pleural effusion in hematological malignancies is rare when compared with solid tumors. We present an unusual case of myeloid sarcoma in which a mediastinal mass with pleural effusion was the initial presentation. A 27 year old gentleman presented with complaints of fever, chest pain and swelling in the anterior chest wall for 6 months. Examination revealed a lump measuring 5 × 5 cm on the left side of the chest wall. Hematological evaluation showed hemoglobin-14.2 g/dL, platelet count-233 × 109/L, TLC-117 × 106/L with normal differential counts. Contrast enhanced computerised tomography (CECT) confirmed the presence of a soft tissue mass in the superior mediastinum abutting against the chest wall. Core biopsy was suggestive of myeloid sarcoma and immunohistochemistry was positive for myeloperoxidase and negative for CD3, CD 20 and CD 23. Pleural fluid analysis showed the presence of malignant cells. Bone marrow examination did not show an excess of blasts. A final diagnosis of extramedullary myeloid sarcoma with malignant pleural effusion was made. The patient was given induction chemotherapy (3 + 7 regimen) with daunorubicin and cytosine arabinoside. Repeat CECT done on day 28 showed complete resolution of pleural effusion and significant reduction in the size of mediastinal mass. The patient has successfully completed three cycles of consolidation therapy following which there has been complete resolution of the mass. He remains asymptomatic on close follow up. 相似文献
147.
Rajdeep Banerjee Sanjay Khandelwal Yukiko Kozakai Bikash Sahu Sanjai Kumar 《Proceedings of the National Academy of Sciences of the United States of America》2015,112(10):3062-3067
Several Plasmodium species exhibit a strong age-based preference for the red blood cells (RBC) they infect, which in turn is a major determinant of disease severity and pathogenesis. The molecular basis underlying this age constraint on the use of RBC and its influence on parasite burden is poorly understood. CD47 is a marker of self on most cells, including RBC, which, in conjunction with signal regulatory protein alpha (expressed on macrophages), prevents the clearance of cells by the immune system. In this report, we have investigated the role of CD47 on the growth and survival of nonlethal Plasmodium yoelii 17XNL (PyNL) malaria in C57BL/6 mice. By using a quantitative biotin-labeling procedure and a GFP-expressing parasite, we demonstrate that PyNL parasites preferentially infect high levels of CD47 (CD47hi)-expressing young RBC. Importantly, C57BL/6 CD47−/− mice were highly resistant to PyNL infection and developed a 9.3-fold lower peak parasitemia than their wild-type (WT) counterparts. The enhanced resistance to malaria observed in CD47−/− mice was associated with a higher percentage of splenic F4/80+ cells, and these cells had a higher percentage of phagocytized parasitized RBC than infected WT mice during the acute phase of infection, when parasitemia was rapidly rising. Furthermore, injection of CD47-neutralizing antibody caused a significant reduction in parasite burden in WT C57BL/6 mice. Together, these results strongly suggest that CD47hi young RBC may provide a shield to the malaria parasite from clearance by the phagocytic cells, which may be an immune escape mechanism used by Plasmodium parasites that preferentially infect young RBC.Malaria, caused by Plasmodium parasites, remains a major cause of mortality and morbidity in the developing world. Among the four principal human Plasmodium species, Plasmodium falciparum is the most virulent, being responsible for more than 90% of malaria-associated deaths. Likewise, Plasmodium species that infect rodents and nonhuman primates also differ widely in their fulminant nature and in the mortality they cause (1–3). How different Plasmodium species have evolved to exhibit this wide array of virulence and disease severity remains one of the major unsolved questions in malaria biology and pathogenesis.One important factor that is associated with Plasmodium parasite burden and disease severity is the age constraint of the host red blood cells (RBC) they infect. The age-based preference for restricted invasion of RBC by the Plasmodium parasite is characterized as young RBC (reticulocyte), aged RBC (mature), or both young and aged RBC. Plasmodium species that preferentially infect and grow inside young RBC generally cause a low-grade, self-resolving infection that is rarely fatal (e.g., Plasmodium vivax and Plasmodium ovale), whereas those that infect both young and aged RBC cause more fulminant infection that can be fatal in the absence of immunity (e.g., P. falciparum) (1, 4–6). Thus, along with host genetic background and immune response, restriction for age-specific RBC invasion is a major determinant of the severity and outcome of malaria infection.Malaria parasites have evolved to use redundant receptors and pathways to invade the RBC. For example, sialic acid (7) and Duffy antigen (8) are the major RBC receptors for invasion of P. falciparum and P. vivax, respectively, although other receptors and invasion pathways are known to exist (9, 10). Although a redundancy in RBC receptor use would ensure successful invasion by mitigating the effects of polymorphism and immune targeting, the reasons behind the RBC age-based preference for invasion are not fully clear and remain a subject of debate.Survival of normal cells through the course of their life cycle is essential to maintain homeostasis, and aberrant cells (e.g., senescent or foreign antigen-expressing cells) are eliminated through a sophisticated programmed cell removal system that relies on the recognition of self and nonself determinants (11). CD47, a cell surface molecule in the Ig superfamily, is ubiquitously expressed on many cell types, including RBC, and is a marker of self to avoid early clearance by phagocytic cells through ligation of signal regulatory protein alpha (12). In contrast, altered expression or conformational changes in CD47 may lead to a molecular switch that triggers a phagocytic signal to remove aged or damaged cells (11). Recent studies have shown that the level of CD47 expression is higher in progenitor cells and declines as they undergo maturation and are subsequently aged (13). This age-dependent difference in CD47 expression shields young cells but allows clearance of aging and damaged cells from the system.CD47 is overexpressed in cancer cells (11, 14, 15), and the CD47–signal regulatory protein alpha interaction is considered a major pathway of immune evasion by tumor cells (15). Administration of anti-CD47 antibodies enabled the phagocytosis of tumor cells in vitro, reduced their growth, and prevented the metastasis of human patient tumor cells (14). In this article, using the murine Plasmodium yoelii nonlethal model, we provide quantitative evidence for age of RBC as the basis for the survival and growth of malaria parasites and provide supporting data that suggest that P. yoelii nonlethal parasites prefer to grow inside younger RBC, which allows them to evade immune clearance by phagocytic cells through a CD47-mediated process, and that CD47 modulates the clearance of malaria infection. To our knowledge, this is the first report that provides a molecular basis for the age-dependent preference for infection of RBC by a Plasmodium parasite and sheds light on its implications for the severity of malaria infection in a host. 相似文献
148.
Rikki Singal A. S. Bawa Rashpal Singh Pradeep Sahu Anupama Gupta 《The Indian journal of surgery》2012,74(6):495-497
We report a 31 year old patient, presented with painful erection since 48 hours. There was no known predisposing factor on history and examination. Surgery for priapism is rarely indicated nowadays but conservative management failed to achieve detumescence in our case. So Winter’s shunt surgery was done which failed then a formal shunt was created between corpora cavernosa and spongiosum which also failed to achieve detumescence. After 4 days - a formal left side cavernosa saphenous shunt procedure was done and detumescence achieved within 24 hrs .Follow up showed good results. 相似文献
149.
INTRODUCTION: Simple cysts of the liver are usually discovered incidentally on abdominal imaging, and asymptomatic simple cysts do not require treatment regardless of size. DISCUSSION: We report a case of a symptomatic simple cyst of the liver complicated by intracystic hemorrhage for which a partial hepatectomy was performed. Treatment of simple hepatic cysts is indicated in the presence of associated symptoms or complications, and inability to exclude a cystic neoplasm requires operative intervention. 相似文献
150.