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1.
 The case of a 14-year-old girl with rhabdomyosarcoma of the right foot is reported. Plain radiography showed a large nonspecific soft tissue tumor between the metatarsals with bowing of the metatarsals away from the mass. MR imaging showed a large soft tissue mass involving the metatarsals. The findings were conflicting, because the tumor had an infiltrative soft tissue mass and bowing of the metatarsals more suggestive of slow expansive growth. Bowing of short tubular bones may be a process similar to cortical saucerization, which is typically seen in Ewing’s sarcoma, and it can be one of the findings of high grade neoplasms, such as embryonal rhabdomyosarcoma.  相似文献   
2.
Globoid cell leukodystrophy (GLD, Krabbe disease) is a severe demyelinating disease caused by a genetic defect of beta-galactocerebrosidase (GALC). To date treatment to GLD is limited to hematopoietic stem cell transplantation. Experimental approaches by means of gene therapy in twitcher mouse, an authentic murine model of human GLD, showed significant but only marginal improvements of the disease. To clarify whether the introduction of GALC could provide beneficial effects on the oligodendrocytes in GLD, we transduced twitcher oligodendrocytes by stereotactically injecting recombinant retrovirus encoding GALC-myc-tag fusion gene into the forebrain subventricular zone of neonatal twitcher mouse. In vivo effects of exogenous GALC on twitcher oligodendrocytes were studied histologically by combined immunostaining for the myc-epitope and the oligodendroglial specific marker, pi form of glutathione-S-transferase, at around 40 days of age. We show here that GALC transduction led to dramatic morphological improvement of the twitcher oligodendrocytes comparing with those in untreated twitcher controls. This study provided direct in vivo evidence that GALC transduction could prevent or correct aberrant morphology of oligodendrocytes in GLD which may be closely related to the dysfunction and/or degeneration of oligodendrocytes and the demyelination in this disease.  相似文献   
3.
Peripheral blood samples from 52 women including 16 with herpes genitalis and 36 healthy persons were studied to enumerate subpopulations of lymphocytes. T lymphocyte counts were done by SRBC rosette tests and B lymphocytes by immunobead rosette tests using antibody-coated polyacrylamide beads. It was found that the mean percentage of «active T lymphocytes was significantly less in the patients with herpes genitalis than in the controls (herpes genitalis; 13.9 ± 6.8%, controls; 25.0 ± 8.3%, p < 0.001). No difference was noted in the percentage of «total» T lymphocytes, «total» B lymphocytes and subsets of B lymphocytes (IgG-, IgA- and IgM-bearing lymphocytes) between the patients and controls. The present findings suggest that cell-mediated immune function associated with «active» T lymphocytes is suppressed in patients with herpes genitalis.  相似文献   
4.
The heteromeric amino acid transporters (HATs) are composed of a light and a heavy subunit linked by a disulfide bridge. The heavy subunits are the SLC3 members (rBAT and 4F2hc), whereas the light subunits are members of the SLC7 family of amino acid transporters. SLC3 proteins are type II membrane glycoproteins (i.e., one single transmembrane domain and the C-terminus located outside the cell) with a bulky extracellular domain that shows homology with alpha-glucosidases. rBAT heterodimerizes with b(0,+)AT (SLC7A9) constituting the amino acid transport b(0,+), the main system responsible for the apical reabsorption of cystine in kidney. The defect in this system causes cystinuria, the most common primary inherited aminoaciduria. 4F2hc subserves various amino acid transport systems by dimerization with different SLC7 proteins. The main role of SLC3 proteins is to help routing of the holotransporter to the plasma membrane. A working model for the biogenesis of HATs based on recent data on the rBAT/b(0,+)AT heterodimeric complex is presented. 4F2hc is a multifunctional protein, and in addition to its role in amino acid transport, it may be involved in other cellular functions. Studies on two SLC7 members (Asc-2 and AGT1) demonstrate heterodimerization with unknown heavy subunits.  相似文献   
5.
CATs and HATs: the SLC7 family of amino acid transporters   总被引:18,自引:0,他引:18  
The SLC7 family is divided into two subgroups, the cationic amino acid transporters (the CAT family, SLC7A1–4) and the glycoprotein-associated amino acid transporters (the gpaAT family, SLC7A5–11), also called light chains or catalytic chains of the hetero(di)meric amino acid transporters (HAT). The associated glycoproteins (heavy chains) 4F2hc (CD98) or rBAT (D2, NBAT) form the SLC3 family. Members of the CAT family transport essentially cationic amino acids by facilitated diffusion with differential trans-stimulation by intracellular substrates. In some cells, they may regulate the rate of NO synthesis by controlling the uptake of l-arginine as the substrate for nitric oxide synthase (NOS). The heterodimeric amino acid transporters are, in contrast, quite diverse in terms of substrate selectivity and function (mostly) as obligatory exchangers. Their selectivity ranges from large neutral amino acids (system L) to small neutral amino acids (ala, ser, cys-preferring, system asc), negatively charged amino acid (system xc) and cationic amino acids plus neutral amino acids (system y+L and b0,+-like). Cotransport of Na+ is observed only for the y+L transporters when they carry neutral amino acids. Mutations in b0,+-like and y+L transporters lead to the hereditary diseases cystinuria and lysinuric protein intolerance (LPI), respectively.  相似文献   
6.
7.
Confronting cisternae of the endoplasmic reticulum recognized in tumor cells of 7 cases of osteosarcoma were presented. They were found in the mitotic cells as well as in the cytoplasms of interphase cells. The more the mitotic cells were observed in 1 μm-thick sections, the more frequently those membranous structures were encountered in the corresponding ultrathin sections. In the interphase cells, such structures were located around Golgi apparatus or close to the nucleus. Occasionally, they were composed of a pair of closely apposed cisternae of the nuclear membrane and the rough endoplasmic reticulum. These results seem to indicate that the nuclear envelope which is disrupted and reformed during mitosis in rapidly proliferating cells takes part in the formation of the confronting cisternae of the endoplasmic reticulum.  相似文献   
8.
9.
The present study examined the effect of cyclosporine (CsA) administered with steroidin vivo on the capacity of peripheral blood mononuclear cells (PBMC) from kidney transplant recipients to generate cytokines and their gene expression at the level of messenger RNA (mRNA). PBMC from CsA-prednisolone (Pred)-treated recipients displayed 66.9% inhibition (54.3±12.4 IU/ml;N=42;P<0.01) of -interferon (-IFN) production compared with normal individuals (134.6±18.6 IU/ml;N=23). Azathioprine (Az)-Pred-treated recipients displayed significantly less inhibition of -IFN generation (96.0±16.1 IU/ml;N=22;P<0.05) than CsA-treated patients. Macrophages (m) from CsA-Pred-treated recipients displayed 60.0% inhibition (5.1±0.7 U/ml;N=20;P<0.01) of interleukin-1 (IL-1) production compared with normal individuals (13.0±2.9 U/ml;N=21). These results were confirmed by the experiments using cDNA probe for -IFN or IL-1 (, ). High levels of -IFN mRNA in phytohemagglutinin (PHA)-stimulated PBMC or IL-1() mRNA in lipopolysaccharide (LPS)-stimulated m were present in normal individuals but not in CsA-treated recipients as judged by hybridization to a cloned human -IFN or IL-1() cDNA probe. These studies demonstrated that combination therapy of CsA with steroid inhibits both -IFN and IL-1 gene expression at the level of mRNA at physiological concentrations.  相似文献   
10.
Although single-lung transplant on the side with better lung function is challenging in patients with significantly asymmetrical lung function between the right and left sides, it sometimes can be a realistic option because of the recipient's condition and from the viewpoint of organ sharing. We report our experience with a successful case of single-lung transplant on the side with a pulmonary perfusion ratio of 89%. The transplant was performed with the patient under central venoarterial extracorporeal membrane oxygenation through a clamshell incision, and the patient had an acceptable short- and long-term outcome with a remarkable improvement of lung function.  相似文献   
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