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51.
Bone marrow houses a multifunctional stromal cell population expressing C-X-C motif chemokine ligand 12 (CXCL12), termed CXCL12-abundant reticular (CAR) cells, that regulates osteogenesis and adipogenesis. The quiescent pre-adipocyte-like subset of CXCL12+ stromal cells (“Adipo-CAR” cells) is localized to sinusoidal surfaces and particularly enriched for hematopoiesis-supporting cytokines. However, detailed characteristics of these CXCL12+ pre-adipocyte-like stromal cells and how they contribute to marrow adipogenesis remain largely unknown. Here we highlight CXCL12-dependent physical coupling with hematopoietic cells as a potential mechanism regulating the adipogenic potential of CXCL12+ stromal cells. Single-cell computational analyses of RNA velocity and cell signaling reveal that Adipo-CAR cells exuberantly communicate with hematopoietic cells through CXCL12-CXCR4 ligand-receptor interactions but do not interconvert with Osteo-CAR cells. Consistent with this computational prediction, a substantial fraction of Cxcl12-creER+ pre-adipocyte-like cells intertwines with hematopoietic cells in vivo and in single-cell preparation in a protease-sensitive manner. Deletion of CXCL12 in these cells using Col2a1-cre leads to a reduction of stromal-hematopoietic coupling and extensive marrow adipogenesis in adult bone marrow, which appears to involve direct conversion of CXCL12+ cells to lipid-laden marrow adipocytes without altering mesenchymal progenitor cell fates. Therefore, these findings suggest that CXCL12+ pre-adipocyte-like marrow stromal cells prevent their premature differentiation by maintaining physical coupling with hematopoietic cells in a CXCL12-dependent manner, highlighting a possible cell-non-autonomous mechanism that regulates marrow adipogenesis. © 2021 American Society for Bone and Mineral Research (ASBMR).  相似文献   
52.
53.
Cultural influences on sex differences in clinical characteristics and symptomatology of schizophrenia were studied among 369 schizophrenic patients from the United States and Turkey. Male schizophrenics were more likely to be single, and were younger than female schizophrenics at onset of symptoms and when first diagnosed, treated and hospitalised in both cultures. Turkish male and female schizophrenics were more ambivalent, inappropriate, "silly", euphoric, depersonalised, dissociated, mute, conceptually disorganised, and exhibiting more flight of ideas and thought than American male and female schizophrenics. Irrelevant thought and stereotypic behaviour were most severe in Turkish male and American female schizophrenics. Hallucinatory behaviour was most intense in Turkish separated, divorced, or widowed female schizophrenics and American married male schizophrenics. Turkish married female and Turkish separated, divorced, or widowed male schizophrenics were most disoriented. Turkish single female schizophrenics were most mute. Turkish separated, divorced, or widowed male schizophrenics showed most intense stupor behaviour.  相似文献   
54.
目的 探讨脑硬死患者急性期血小板膜P -选择素 (CD6 2p)的表达及其与临床神经功能缺损程度的关系。方法 用流式细胞术测定 41例急性期脑梗死患者血小板膜CD6 2 p的表达。 结果 轻、中、重型脑梗死患者CD6 2 p的表达分别为 (1.38± 0 .2 9) %、(3.15± 1.5 8) %、(10 .46± 5 .0 7) % ,与正常对照组 (1.5 6± 0 .17) %比 ,轻型脑梗死患者CD6 2p的表达无显著性差异 (P >0 .0 5 ) ,中、重型脑梗死患者CD6 2 p的表达显著升高 (P <0 .0 5和0 .0 1)。结论 脑梗死患者急性期血小板膜CD6 2 p的表达与临床神经功能缺损程度有关。  相似文献   
55.
储雪雁  霍俊 《医学争鸣》2000,21(5):648-648
0 引言 我院首次收住1例产后出血合并弥漫性血管内凝血(DIC)患者,经抢救,患者脱险.1 病例报告 女,16岁,未婚,妊7mo,于1999-01-30入院,要求终止妊娠.入院后一般检查无异常,妇科查:阴道正常,宫底位于剑下三指,胎心清,规律.实验室检查:Hb115g.L-1,BT1min,CT2min,WBC14.7×109.L-1.入院第4日,放置水囊,32h后,顺娩一婴,会阴度裂伤.阴道壁无撕裂伤,胎盘子面娩出完整,阴道出血30mL,揉按子宫,阴道仍然出血不止,BP9/7kPa,P140/min.发现阴道流出非血凝块,急诊Hb46g.L-1,Pt31×109.L-1,凝血酶元时间22s,纤维蛋白元1~3g.L-1,尿RBC9~12.…  相似文献   
56.
A 74-year-old woman with corticobasal degeneration (CBD) had a 9-year history of progressive loss of strength and rigidity of her right hand and then arm, followed by speech difficulties, dyskinesia, rigidity, spasticity and weakness of the ipsilateral lower limb, ultimately also involving the apposite side. She later developed supranuclear gaze palsy. Her memory remained intact during most of the duration of her disease. Laboratory tests and anti-Parkinsonian medications were not helpful. At autopsy, frontal lobe atrophy, discoloration of putamen (Pt) and pallor of substantia nigra (Sn) were observed. Neuronal loss and gliosis were extensive in motor cortex and milder in frontal cortex, abruptly ending at the central sulcus and junction of cingulate gyrus. Achromatic neurons were present. Neuronal loss and gliosis were seen in Pt and Sn and corticobasal inclusions in Sn. Numerous Gallyas/tau-positive, Bielschowsky/ubiquitin-negative coil, sickle, or coma-shaped tangles and thread-like processes were found in affected cortex, Pt and Sn. Some of the tangles were in neurons, but most occurred in astroglia, and their processes. The presence of Gallyas/tau-positive glia in CBD may have the same diagnostic significance as in progressive supranuclear palsy, analogous to the argyrophilic ubiquinated inclusions in oligodendroglia in multisystem atrophy. We suggest that in CBD: (1) cytoskeletal protein metabolism in neurons and glia can simultaneously be perturbed in certain neurodegenerative diseases, and (2) the astrocytosis in CBD may not be simply a reactive process but an integral part of the disease.  相似文献   
57.
In this report, we describe the analysis of clonality performed using a PCR-based approach in a group of cutaneous T-cell lymphomas including a case of localised pagetoid reticulosis expressing the gamma delta T-cell receptor. For our PCR analysis DNA was extracted from frozen tissue of 10 cases of cutaneous T-cell lymphomas and subjected to polymerase chain reaction amplification using primers recognizing conserved sequences of the variable and joining regions of the T-cell receptor gamma chain gene. PCR products were then analyzed by high resolution non-denaturing polyacrylamide gel electrophoresis. Clonal TCR gamma gene rearrangements were detected in all the cases investigated including the case of localised pagetoid reticulosis. The PCR-based approach used in this study may provide an alternative to conventional Southern blot analysis for the analysis of cutaneous T-cell lymphomas as it is easy to perform and requires only minimal amounts of DNA. The findings in localized pagetoid reticulosis are consistent with the proliferation of monoclonal T-cells in lesional skin of this condition and provide evidence for the lymphoproliferative nature of this clinically benign disorder.  相似文献   
58.
Athletic training issues in synchronized swimming   总被引:1,自引:0,他引:1  
Synchronized swimming is an aesthetic sport comparable to, in terms of its physical demands, those sports that require high metabolic conditioning. This article discusses injuries related to the demanding combination of strength, speed, and flexibility, including shoulder instability, lower back injuries, medial stress syndromes of the knee, and injury management treatment regimens.  相似文献   
59.
The ribs, sternum, and vertebrae all play an important role in stabilizing the thorax. Failure of one of these components places additional stress on the other supporting structures. We present a case of a 62-year-old man with multiple myeloma and osteopenia who sustained fractures to all three components.  相似文献   
60.
Lentiviral vectors infect quiescent cells and allow for the delivery of genes to discrete brain regions. The present study assessed whether stable lentiviral gene transduction can be achieved in the monkey nigrostriatal system. Three young adult Rhesus monkeys received injections of a lentiviral vector encoding for the marker gene beta galatosidase (beta Gal). On one side of the brain, each monkey received multiple lentivirus injections into the caudate and putamen. On the opposite side, each animal received a single injection aimed at the substantia nigra. The first two monkeys were sacrificed 1 month postinjection, while the third monkey was sacrificed 3 months postinjection. Robust incorporation of the beta Gal gene was seen in the striatum of all three monkeys. Stereological counts revealed that 930,218; 1,192,359; and 1,501,217 cells in the striatum were beta Gal positive in monkeys 1 (n = 2) and 3 (n = 1) months later, respectively. Only the third monkey had an injection placed directly into the substantia nigra and 187,308 beta Gal-positive cells were identified in this animal. The injections induced only minor perivascular cuffing and there was no apparent inflammatory response resulting from the lentivirus injections. Double label experiments revealed that between 80 and 87% of the beta Gal-positive cells were neurons. These data indicate that robust transduction of striatal and nigral cells can occur in the nonhuman primate brain for up to 3 months. Studies are now ongoing testing the ability of lentivirus encoding for dopaminergic trophic factors to augment the nigrostriatal system in nonhuman primate models of Parkinson's disease.  相似文献   
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