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11.
Since intimal smooth muscle cells (SMC) are an important feature of atherosclerotic fibrofatty plaques, we tested the hypothesis that endothelial cells (EC) regulate SMC proliferation in the process of neointimal formation. Using a porcine thoracic aortic organ culture (OC) system, we previously showed in a preliminary study that short-term porcine aortic explants incubated in 5% fetal bovine serum for 7 days promote neointimal formation only in the presence of endothelium or in conditioned media collected from proliferating OC with endothelium present. We now report that these organ cultures can be maintained in culture for up to 4 weeks. The surface cells stained positively for dil-acetylated-low-density lipoprotein throughout the 4-week period indicating the continued presence of EC while the neointimal cells stained positively for the smooth muscle actin-specific monoclonal antibodies alpha-SM1 and HHF-35 indicating their smooth muscle nature. The number of EC did not change during the 4-week incubation period, however, EC turnover peaked at 5 days and remained elevated but constant throughout. The number of intimal SMC doubled between day 0 (18.4 +/- 0.2 cells/field) and day 7 (41.5 +/- 0.9) and between day 7 and day 14 (75.8 +/- 10.1). The intimal SMC number then stabilized thereafter (day 21: 79.5 +/- 7.8, day 28: 73.8 +/- 12.1). Cell proliferation played a large part since autoradiography studies using nondenuded OC showed that intimal SMC thymidine index on day 0 was 1.4% +/- 0.4, peaked at the end of day 5 (25.7% +/- 4.1) and gradually decreased thereafter. The peak in the intimal SMC thymidine index occurred during a period of high EC turnover (maximum EC thymidine index on day 5: 21.8% +/- 2.1), and the stabilization of intimal SMC number observed beyond 2 weeks of incubation occurred when EC replication was reduced (day 14: 6.7% +/- 0.21). Incubation of organ cultures denuded of their endothelium in 5% fetal bovine serum showed a marked decrease in neointimal formation. However, denuded OC when incubated in conditioned medium collected from 4-day-old nondenuded OC (4DCM) enhanced neointimal formation of denuded OC. In contrast, the neointima of denuded OC incubated in 24-day-old nondenuded OC conditioned medium was similar to that of controls. The thymidine index of intimal SMC of denuded OC treated with 4DCM was markedly higher than that found with the control treatment at all time points.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   
12.
Somatic cell nuclear transfer (scNT) is a useful way to create cloned animals. However, scNT clones exhibit high levels of phenotypic instability. This instability may be due to epigenetic reprogramming and/or genomic damage in the donor cells. To test this, we produced transgenic pig fibroblasts harboring the truncated human thrombopoietin (hTPO) gene and used them as donor cells in scNT to produce first-generation (G1) cloned piglets. In this study, 2,818 scNT embryos were transferred to 11 recipients and five G1 piglets were obtained. Among them, a clone had a dimorphic facial appearance with severe hypertelorism and a broad prominent nasal bridge. The other clones looked normal. Second-generation (G2) scNT piglets were then produced using ear cells from a G1 piglet that had an abnormal nose phenotype. We reasoned that, if the phenotypic abnormality of the G1 clone was not present in the G2 and third-generation (G3) clones, or was absent in the G2 clones but reappeared in the G3 clones, the phenotypic instability of the G1 clone could be attributed to faulty epigenetic reprogramming rather than to inherent/accidental genomic damage to the donor cells. Blastocyst rates, cell numbers in blastocyst, pregnancy rates, term placenta weight and ponderal index, and birth weight between G1 and G2 clones did not differ, but were significantly (P < 0.05) lower than control age- and sex-matched piglets. Next, we analyzed global methylation changes during development of the preimplantation embryos reconstructed by donor cells used for the production of G1 and G2 clones and could not find any significant differences in the methylation patterns between G1 and G2 clones. Indeed, we failed to detect the phenotypic abnormality in the G2 and G3 clones. Thus, the phenotypic abnormality of the G1 clone is likely to be due to epigenetic dysregulation. Additional observations then suggested that expression of the hTPO gene in the transgenic clones did not appear to be the cause of the phenotypic abnormality in the G1 clones and that the abnormality was acquired by only a few of the G1 clone's cells during its gestational development.  相似文献   
13.
Genetically altering the disease vector status of insects using recombinant DNA technologies is being considered as an alternative to eradication efforts. Manipulating the endogenous immune response of mosquitoes such as the temporal and special expression of antimicrobial peptides like cecropin may result in a refractory phenotype. Using transgenic technology a unique pattern of expression of cecropin A (cecA) in Anopheles gambiae was created such that cecA was expressed beginning 24 h after a blood meal in the posterior midgut. Two independent lines of transgenic An. gambiae were created using a piggyBac gene vector containing the An. gambiae cecA cDNA under the regulatory control of the Aedes aegypti carboxypeptidase promoter. Infection with Plasmodium berghei resulted in a 60% reduction in the number of oocysts in transgenic mosquitoes compared with nontransgenic mosquitoes. Manipulating the innate immune system of mosquitoes can negatively affect their capacity to serve as hosts for the development of disease-causing microbes.  相似文献   
14.
This study was undertaken in order to estimate the incidence of leukemia among Koreans. Medical records were studied of patients with diagnoses of either ICD-9 038 (septicemia), or 204-208 (leukemias), or 284 (aplastic anemia), or 289 (other diseases of the blood and blood-forming organs) in the claims sent in by medical care institutions throughout the country to the Korea Medical Insurance Corporation (KMIC) during the period from January 1, 1986 to December 31, 1987. These records were abstracted in order to identify and confirm new cases of leukemia among the beneficiaries of KMIC, which covers about 10% of the whole Korean population. Using these data from the KMIC, the incidence rates of leukemia among Koreans were estimated as of July 1st, 1986 to June 30, 1987. The crude incidence rate of all types of leukemia among Koreans is estimated to be 3.45 (95% CI; 0.77-9.55) and 2.29 (95% CI; 0.28-7.81) per 100,000 in males and females, respectively. The cumulative rate for the age span 0-64 is 0.25% in males and 0.18% in females, and for the age span 0-74, 0.35% in males and 0.23% in females. The adjusted rates for the standard world population are 3.90 and 2.48 per 100,000 in males and females, respectively. The relative frequencies by type are 51.5% for AML, 21.6% for ALL, 20.2% for CML, and only 1.5% for CLL. The incidence patterns of various types of leukemia, of which this is the first report in Korea, are analyzed and presented.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
15.
Plasmacytoid T-cell lymphoma (PTL) is a rare lymphoma with unique morphologic, immunologic, and clinical features. Thus far, only three cases have been reported, each terminating in myeloid leukemia. The macrophage/monocyte rather than T-cell origin of "plasmacytoid T-cells" in reactive lymph nodes has been suggested in the past, but there has been no extensive investigation to demonstrate whether the PTLs are also of this lineage. The authors now report on a patient with PTL who had a long history of clinically stable idiopathic myelofibrosis. Immunocytochemical staining of the neoplastic plasmacytoid cells, with a large panel of monoclonal antibodies used on fresh-frozen and paraffin-embedded tissue sections, showed that the neoplastic cells expressed several macrophage/monocyte-associated markers, i.e., CD31, CD36 (thrombospondin receptor), and CD68 (KP1). Other markers of the macrophage/monocyte lineage (e.g., CD11b, CD11c, CD16) were absent. The neoplastic cells lacked B-cell-associated antigens and lacked most T-cell-associated markers, with the exception of CD2 and CD4. These findings are in close agreement with those of previous studies on normal plasmacytoid T-cells and support the macrophage/monocytic origin of PTL. Molecular hybridization studies provided additional support for the nonlymphoid origin of the plasmacytoid cells by demonstrating the absence of T-cell-receptor beta-chain and immunoglobulin heavy-chain gene rearrangements in the neoplastic cells. The results of the authors' studies indicate that "plasmacytoid T-cell lymphoma" associated with a chronic myeloproliferative disorder is of macrophage/monocyte lineage.  相似文献   
16.
The present study was performed to determine whether the effects induced by GABA(B) receptor-acting drugs would be related with the alteration in GABA(B) receptor expression in the hippocampus using Mongolian gerbil, a genetic epilepsy model. The distribution patterns of both GABA(B) receptor 1A/B and GABA(B)receptor 2 immunoreactivities were similarly detected in the hippocampi of normal and seizure-prone gerbils. Following baclofen (GABA(B) receptor agonist) or phaclofen (GABA(B) receptor antagonist) treatment, GABA(B) receptor immunoreactivities were decreased or increased by dose-dependent manners, respectively. Vigabatrin (GABA transaminase inhibitor) or 3-mercaptopropionic acid (GAD inhibitor) treatment did not affect GABA(B) receptor expressions. These findings suggest that GABA(B) receptor expression in the gerbil hippocampus may be altered by baclofen or phaclofen treatment.  相似文献   
17.
The ethanol extract of potato tubers (Solanum tuberlosum L.) has been evaluated for antinociceptive and anti-inflammatory activities in mice. The acute treatment of mice with an ethanolic extract from the potato tuber at doses of 100 and 200 mg/kg, by oral administration, produced a significant anti-nociceptive effect in the acetic acid-induced writhing, formalin-induced pain licking and hot plate-induced pain. Also, the ethanolic extract of potato tubers significantly inhibited both carrageenan- and formalin-induced inflammation in mice as well as arachidonic acid-induced ear edema in mice. These inhibitions were statistically significant (p<0.05). These results provide support for the use of the ethanol extract of potato tuber in relieving inflammatory pain, and insight into the development of new agents for treating inflammatory diseases.  相似文献   
18.
The purpose of this study was to determine whether 20 patients who received an early postmastectomy rehabilitation treatment program showed more improvement in range of shoulder motion and functional activities than 13 patients who received instruction for exercise only. Data were obtained at preoperatively, three days after operation, at discharge and at postdischarge one month for each patient on parameters such as range of motion of the ipsilateral shoulder joint, upper extremity circumferential measurements, as well as 10 elements of shoulder function. Postoperatively, both groups showed an increased range of motion of the shoulder joint and improved functional activities, but the group that received postoperative rehabilitation management had a better range of shoulder motion and less difficulty in five items for functional assessment. This study also showed that an early rehabilitation program did not increase postoperative complications. We concluded that an early rehabilitation program or intensive instruction program only by a well-trained physical therapist or physiatrist was beneficial to postmastectomy patients in regaining the function and range of shoulder motion, and significantly better in a rehabilitation group.  相似文献   
19.
Thrombin-induced platelet microbicidal protein (tPMP-1) is a small, cationic peptide released from rabbit platelets exposed to thrombin in vitro. tPMP-1 is microbicidal against a broad spectrum of bloodstream pathogens, including Staphylococcus aureus. Preliminary evidence suggests that tPMP-1 targets and disrupts the staphylococcal cytoplasmic membrane. However, it is not clear if the cytoplasmic membrane is a direct or indirect target of tPMP-1. Therefore, we assessed the in vitro activity of tPMP-1 versus protoplasts prepared from logarithmic-phase (LOG) or stationary-phase (STAT) cells of the genetically related S. aureus strains 19S and 19R (tPMP-1 susceptible and resistant, respectively). Protoplasts exposed to tPMP-1 (2 microg/ml) for 2 h at 37 degrees C were monitored for lysis (decrease in optical density at 420 nm) and ultrastructural alterations (by transmission electron microscopy [TEM]). Exposure to tPMP-1 resulted in substantial lysis of LOG but not STAT protoplasts of 19S, coinciding with protoplast membrane disruption observed by TEM. Thus, it appears that tPMP-1-induced membrane damage is influenced by the bacterial growth phase but is independent of the staphylococcal cell wall. In contrast to 19S, neither LOG nor STAT protoplasts of 19R were lysed by tPMP-1. tPMP-1-induced membrane damage was further characterized with anionic planar lipid bilayers subjected to various trans-negative voltages. tPMP-1 increased conductance across bilayers at -90 mV but not at -30 mV. Once initiated, a reduction in voltage from -90 to -30 mV diminished conductance magnitude but did not eliminate tPMP-1-mediated membrane permeabilization. Therefore, tPMP-1 appears to directly target the staphylococcal cytoplasmic membrane as a primary event in its mechanism of action. Specifically, tPMP-1 likely leads to staphylococcal death, at least in part by permeabilizing the bacterial membrane in a voltage-dependent manner.  相似文献   
20.
The T-cell receptor β locus (TCRB) on chromosome 7q35 was studied as a candidate region for genetic susceptibility to type 1 insulin-dependent diabetes (IDDM). A highly polymorphic microsatellite marker mapping to the TCRBV6.7 gene and a TCRB C-region RFLP were used to genotype the members of a total of 21 multiplex IDDM families from two different geographical areas. There was no evidence to support linkage to either of these markers with IDDM, and conventional two-point analysis excluded linkage to the telomeric end of the TCRB complex, in the region of the highly informative TCRBV6.7 marker. There was significant linkage of IDDM to the class II HLA-D locus with significant lod scores >3.0 obtained for the HLA-DRB1 and HLA-DQB1 genes. Affected sib-pair (ASP) and transmission disequilibrium (TDT) association tests confirmed these findings.  相似文献   
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