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591.
592.
Yoshimoto M Montecino-Rodriguez E Ferkowicz MJ Porayette P Shelley WC Conway SJ Dorshkind K Yoder MC 《Proceedings of the National Academy of Sciences of the United States of America》2011,108(4):1468-1473
The majority of B lymphocytes in the adult mouse are generated in the bone marrow from hematopoietic stem cells (HSCs) that first appear in the aorta-gonado-mesonephros region of the fetus on embryonic day (E) 10.5-11. Comparatively less is known about B-cell development during embryogenesis. For example, which specific embryonic tissues participate in B lymphopoiesis and whether hematopoietic differentiation is skewed toward specific B-cell subsets in the embryo are unanswered questions, because the systemic circulation is initiated early during embryogenesis, resulting in an admixture of cells potentially originating from multiple sites. We demonstrate, using Ncx1(-/-) mice that lack systemic blood circulation, that the E9 yolk sac (YS) and the intra-embryonic para-aortic splanchnopleura (P-Sp) tissues independently give rise to AA4.1(+)CD19(+)B220(lo-neg) B progenitor cells that preferentially differentiate into innate type B-1 and marginal zone (MZ) B cells but not into B-2 cells upon transplantation. We have further demonstrated that these B-1 progenitor cells arise directly from YS and P-Sp hemogenic endothelium. These results document the initial wave of innate B lymphopoietic progenitor cells available for seeding the fetal liver at E11. The results of these studies expand our knowledge of hemogenic endothelial sites specifying distinct B-1 and MZ cell fates apart from B-2 cells and independent of an HSC origin during development. 相似文献
593.
Gessi M Setty P Bisceglia M zur Muehlen A Lauriola L Waha A Giangaspero F Pietsch T 《The American journal of surgical pathology》2011,35(4):573-582
Advances in understanding the molecular basis of primitive neuroectodermal tumors of the central nervous system (CNS-PNET) biology are critical to improve patient outcome. Recently, new data on their molecular features have been reported, suggesting that supratentorial PNET (s-PNET) in adult patients may represent a specific tumor entity among CNS-PNETs. In this study, we analyzed the clinicopathologic and molecular features of 12 cases of s-PNET in adult patients. The follow-up analysis showed that these tumors have an aggressive clinical behavior. At the histopathologic level, they resembled their pediatric counterpart, showing a variable spectrum of neuronal differentiation. These cases did not show astrocytic differentiation; therefore, they did not qualify for the differential diagnosis of glioblastoma variants. The tumors were also screened for mutation of TP53, IDH1, IDH2, and β-catenin, using single strand conformation polymorphism-based and sequencing assays, and were analyzed for c-myc/N-myc gene copy numbers with a quantitative polymerase chain reaction-based method. The strand conformation polymorphism-based mutational analysis showed that 5 tumors harbored TP53 mutations. In 2 cases, a mutation at codon 132 of the IDH1 gene was also found. No mutations of the β-catenin or IDH2 genes were identified. No cases presented c-myc or N-myc amplifications. Only 1 case presented overexpression of epidermal growth factor receptor. In conclusion, our data show a high incidence of TP53 mutations in this group of tumors and show, in comparison with pediatric s-PNET, the absence of amplification of the c-myc/N-myc genes, indicating that s-PNET in adult patients may represent a specific subset of tumors among CNS-PNETs. 相似文献
594.
595.
Intra-abdominal ingested foreign bodies are usually an incidental finding, typically encountered in mentally challenged patients. We present the case of a 65-year-old mentally sound woman who presented with recurrent abdominal pain and a lump in the hypogastrium. Evaluation revealed a rectus sheath abscess extending to the peritoneum, with a foreign body in situ. On enquiry, the patient revealed that she had accidentally ingested a tailoring needle 17 years ago. This case illustrates an unusual presentation of an ingested foreign body as a rectus sheath abscess after a long duration. 相似文献
596.
Baliga S Shenoy S Prashanth HV Dominic SR 《Journal of the Indian Medical Association》2011,109(2):118-119
The incidence of non-typhoidal salmonellosis has markedly increased in the past decade. Localised infection develops in approximately 5-10% of persons with salmonella bacteraemia. In this report, a 4-year-old female child suffering from acute lymphoid leukaemia is presented with high grade intermittent fever. Pustular lesions were observed over the right side of the scalp. The scalp abscess was drained and pus was sent for culture and sensitivity. Culture grew Salmonella typhimurium. Blood culture also grew the same organism. She had an uneventful recovery after treatment. 相似文献
597.
Neuronal ceroid lipofuscinosis is a group of progressive neurodegenerative disorders characterized by accumulation of ceroid lipopigment in lysosomes in neurons and other cell types. This study is a retrospective review of charts of patients with a diagnosis of infantile and late-infantile neuronal ceroid lipofuscinosis seen between January 2009 and December 2011. Of the 16 patients, 5 had infantile type and 11 had late-infantile neuronal ceroid lipofuscinosis. Diagnosis was confirmed by appropriate enzyme assay. Clinical presentation was quite varied. Common presenting features included refractory seizures, developmental delay/regression, and abnormal movements. Visual failure was not common in the present case series, and novel neuroimaging finding in the form of isolated dentate nucleus hyperintensities were noted. During follow-up, all patients had a progressive downhill course and one patient died. Prenatal diagnosis could be offered to one family. This study suggests that infantile and late-infantile neuronal ceroid lipofuscinosis is not uncommon in this region of the country and the phenotype may be different. 相似文献
598.
Prashanth GP 《Journal of the American Academy of Dermatology》2012,66(5):854-5; author reply 855-6
599.
Vinutha B Prashanth D Salma K Sreeja SL Pratiti D Padmaja R Radhika S Amit A Venkateshwarlu K Deepak M 《Journal of ethnopharmacology》2007,109(2):359-363
Seventy-six plant extracts including methanolic and successive water extracts from 37 Indian medicinal plants were investigated for acetylcholinesterase (AChE) inhibitory activity (in vitro). Results indicated that methanolic extracts to be more active than water extracts. The potent AChE inhibiting methanolic plant extracts included Withania somnifera (root), Semecarpus anacardium (stem bark), Embelia ribes (Root), Tinospora cordifolia (stem), Ficus religiosa (stem bark) and Nardostachys jatamansi (rhizome). The IC(50) values obtained for these extracts were 33.38, 16.74, 23.04, 38.36, 73.69 and 47.21mug/ml, respectively. These results partly substantiate the traditional use of these herbs for improvement of cognition. 相似文献
600.
Microsurgical free tissue transfer is progressing rapidly and is being used more frequently the world over. Monitoring these cases is crucial for a satisfactory outcome. More sophisticated methods are available for monitoring, though they are often expensive. We propose a novel technique using digital photography and the Internet to offer a reliable and cost-effective method to monitor free-tissue transfers. During an 8-month period, 163 microvascular procedures were monitored using this technique. Serial photographs taken were stored in a separate case folder and sent to the surgeon as deemed necessary.Analysis of the 67 cases is presented. Five reexplorations were done. The early diagnosis of venous congestion was possible using this technique. Timely intervention contributed to the success of the reexplorations, and these flaps could be salvaged. The file size of images was in the range of 1 MB to 6 MB. The file size of a set of photographs was usually around 7 MB to 9 MB. These were sent across the asymmetric digital subscriber line Internet lines.The use of the digital images and the Internet allows reconstructive surgeons to have a reliable picture of the state of their free-tissue transfers. This allows decreasing observer error and saves valuable time which otherwise needs to be spent to verify situations of doubt. 相似文献