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51.
The p53 tumor-suppressor protein plays an integral role in apoptosis. Perturbations in peripheral lymphocyte (PL) apoptosis
may be associated with rheumatoid arthritis (RA). Polymorphisms at codon 72 of p53 (arginine (Arg72) to proline transition)
confers differences in mitochondrial translocation and apoptosis inducing capabilities of p53 in vitro. We examined associations
of this polymorphism with PL apoptosis, mitochondrial depolarization, and clinical markers of disease activity in a cohort
of black South African RA patients. Genotypes were determined by polymerase chain reaction-restriction fragment length polymorphism.
PL apoptosis was measured using the annexin-V assay and mitochondrial membrane potential with the JC-1 assay. Clinical and
laboratory parameters were recorded for all patients. Statistical differences in these parameters were investigated according
to genotype. Genotype distribution did not differ significantly between RA patients and controls (Arg/Arg, Arg/Pro, Pro/Pro:
12%, 46%, and 42% versus 3%, 34%, and 63%), despite significantly higher frequency of the Arg72 allele in patients (p = 0.0406). There was no significant difference in PL apoptosis and mitochondrial depolarization based on p53 codon 72 genotype.
In addition, clinical markers of disease activity were not significantly different between genotypes. We conclude that p53
codon 72 genotype does not influence PL apoptosis or mitochondrial depolarization and is not associated with clinical markers
of disease in RA. 相似文献
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53.
Lucretia S. Mongal M.D. Reema Salat M.D. Ather Anis M.D. Barry C. Esrig M.D. † Mehmet Oz M.D. † Marc Klapholz M.D. Pierre Maldjian‡ Muhamed Saric M.D. Ph.D. F.A.C.C. F.A.S.E. § 《Echocardiography (Mount Kisco, N.Y.)》2009,26(8):973-976
We report the case of an enormous right atrial hemangioma in an asymptomatic 42-year-old woman. The diagnosis was made by echocardiogram after the patient was found to have an abnormal EKG during a routine medical exam. The hemangioma is the largest described in English literature. The tumor was surgically resected and the patient did well postoperatively. In this case report, we discuss the discovery of the tumor and treatment of our patient. A brief discussion of cardiac hemangiomas follows. 相似文献
54.
Mody RP 《Journal of the Indian Medical Association》2002,100(9):569-572
Oesophageal cancer is one of the most challenging pathological conditions confronting the surgeon. With advances in imaging techniques, correct evaluation is possible pre-operatively, which helps in planning of treatment and thereby improving overall survival. Treatment now-a-days is multimodality, but still surgery remains the mainstay of the treatment. Usually very less number of patients are amenable to surgical resection and in remainder, palliative treatment remains the primary aim of treatment. Chemoradiation has got some role as in some seen recent trials. Novel drugs, which target at molecular level, are in research phase at present. 相似文献
55.
Kai Ihnken M.D. Kiyozo Morita M.D. Gerald D. Buckberg M.D. Alon Aharon M.D. Hillel Laks M.D. Anthony L. Panos M.D. Davis C. Drinkwater M.D. Reema Chugh M.D. Dario Del Rizzo M.D. Thomas A. Salerno M.D. 《Journal of cardiac surgery》1994,9(1):15-25
Concern over myocardial damage from simultaneous arterial (antegrade) and coronary sinus (retrograde) perfusion has led to alternating between these delivery routes to maximize their individual benefits. Based upon predominant retrograde drainage via Thebesian veins, this study: (1) confirms experimentally the safety of simultaneous arterial and coronary sinus perfusion; and (2) reports initial clinical application of this combined strategy in 155 consecutive patients. Experimental: Five mini-pigs (25 to 30 kg) underwent 1 hour of aortic clamping with simultaneous aortic and coronary sinus perfusion at 200 mUmin with normal blood (37°C) before and after 30 minutes of perfusion with either warm (37°C) or cold (4°C) blood cardioplegia. Coronary sinus pressure was always less than 30 mmHg. There was no right or left ventricular edema, lactate production, or lipid peroxidation as transmyocardial and myocardial conjugated dienes were unaltered, and postbypass recovered left ventricular end-systolic elastance (conductance catheter) and preload recruitable stroke work Index 101%± 3% and 109%± 90%, respectively. Clinical: Simultaneous arteriaVcoronary sinus perfusion was used in 155 consecutive high risk patients (New York Heart Association Class III to IV) undergoing isolated coronary artery bypass grafting (CABG) (n = 109) and CABG + valve replacementlrepair or aneurysm (n = 46). Included were 16 patients in cardiogenic shock and 24 undergoing reoperation. Mean aortic clamping time averaged 90 ± 4 minutes (range 30 to 207), with 3.5 ± 0.1 grafts per patient; all anastomoses were performed with the aorta clamped. Cold intermittent blood cardioplegia was used for distal anastomoses and valve implantationhepair in 123 patients, and warm continuous blood cardioplegia was used in 32 patients. Following a warm cardioplegic reperfusate, all patients received warm non-cardioplegic blood perfusion simultaneously via grafts and coronary sinus. Coronary sinus pressure was always less than 40 mmHg. Of 18 patients requiring postoperative mechanical circulatory support (IABP), 16 had IABP placed preoperatively for cardiogenic shock. There were three postoperative myocardial infarctions (2%), and six patients died (3.9% mortality). Conclusion: These experimental and clinical findings overcome perceived concerns about myocardial damage from simultaneous arterial and coronary sinus perfusion, and suggest this approach may add to the armamentarium of cardioprotective strategies. (J Card Surg 1994;9:15–25) 相似文献
56.
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58.
Chanda B Blunck R Faria LC Schweizer FE Mody I Bezanilla F 《Nature neuroscience》2005,8(11):1619-1626
The development of genetically encoded fluorescent voltage probes is essential to image electrical activity from neuronal populations. Previous green fluorescent protein (GFP)-based probes have had limited success in recording electrical activity of neurons because of their low sensitivity and poor temporal resolution. Here we describe a hybrid approach that combines a genetically encoded fluorescent probe (membrane-anchored enhanced GFP) with dipicrylamine, a synthetic voltage-sensing molecule that partitions into the plasma membrane. The movement of the synthetic voltage sensor is translated via fluorescence resonance energy transfer (FRET) into a large fluorescence signal (up to 34% change per 100 mV) with a fast response and recovery time (0.5 ms). Using this two-component approach, we were able to optically record action potentials from neuronal cell lines and trains of action potentials from primary cultured neurons. This hybrid approach may form the basis for a new generation of protein-based voltage probes. 相似文献
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60.
The utility of p16INK4a and Ki-67 staining on cell blocks prepared from residual thin-layer cervicovaginal material 总被引:4,自引:0,他引:4
BACKGROUND: Cell blocks can be prepared from residual thin-layer cervicovaginal (ThinPrep) material and can be used in immunohistochemical staining assays for p16INK4a and Ki-67, which are surrogate markers related to human papillomavirus infection and cell proliferation, respectively. The objectives of the current study were 1) to investigate the feasibility and the role of cell block preparations in identifying significant neoplastic and preneoplastic lesions of the uterine cervix and 2) to assess the feasibility of using p16INK4a and Ki-67 immunohistochemical staining patterns on cell blocks to identify significant preneoplastic cervical lesions. METHODS: Cervicovaginal cytology specimens from 85 patients were analyzed. Cytologic diagnoses based on ThinPrep Papanicolaou test results were as follows: squamous cell carcinoma was diagnosed in 3 specimens, high-grade squamous intraepithelial lesions (HSIL) were diagnosed in 27 specimens, low-grade squamous intraepithelial lesions (LSIL) were diagnosed in 20 specimens, and atypical squamous cells of uncertain significance (ASCUS) were diagnosed in 11 specimens. Diagnoses of negativity for intraepithelial lesions or malignancy (NILM) were made in 24 specimens. Cell block sections were stained with hematoxylin and eosin and were immunostained with antibodies against p16INK4a protein and Ki-67 antigen. RESULTS: The cytomorphologic diagnoses made using cell block preparations were as follows: SCC in 2 specimens, HSIL in 20 specimens, LSIL in 30 specimens, NILM in 32 specimens, and no diagnosis in 1 specimen. In 62 cases (73%), the diagnoses made using cell block preparations were in agreement with the ThinPrep diagnoses. Immunostaining of cell blocks for p16INK4a and Ki-67 exhibited a statistically significant association (P < 0.05) with the presence of significant lesions on either cell block or ThinPrep analysis. CONCLUSIONS: To the authors' knowledge, p16INK4a has not been analyzed previously in ThinPrep cell blocks, and the correlation between Ki-67 expression and cell block diagnoses also has not been reported previously. The current results indicate that cell blocks prepared from residual ThinPrep material represent an additional reliable diagnostic tool in the evaluation of cervical samples. Furthermore, immunohistochemical studies may be helpful in differentiating significant preneoplastic changes from other cervical lesions, such as atrophy. 相似文献