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1.
Transesophageal echocardiography was conducted to determine the systolic pattern of the anterior mitral leaflet in patients with flat chest, and to differentiate it from that associated with mitral valve prolapse. The fronto-sagittal index (an index of chest flattening) was determined in 50 subjects using chest radiographs, and was used to classify them into a flat chest group (index < 0.38, n = 28) and a normal chest group (index ≥ 0.38, n = 22). We then used transesophageal echocardiography to examine the anterior leaflet in these subjects. A significant positive correlation was observed between the fronto-sagittal index and the short-to long-axis diameter ratio of the left ventricle in all patients. These parameters, and the left atrial dimension were lower in the flat than the normal chest group. The clear zone area of the anterior leaflet during mid-to late-systole was significantly larger in the flat chest group. However, no intergroup differences existed in the rough zone area of the anterior leaflet or in the middle scallop area of the posterior leaflet. Mitral regurgitation was observed in 20 and 12 subjects in the flat and normal chest groups, respectively. The maximum mitral regurgitant area did not differ between the two groups. The clear zone area of the anterior leaflet increased significantly following inhalation of amyl nitrite in 22 subjects of both groups, but the other areas did not increase. The mitral regurgitant area decreased or disappeared after amyl nitrite at a similar rate in each group. Thus, the decrease in the antero-posterior dimension of the thorax in subjects with flat chest affects the systolic pattern of the clear zone of the anterior leaflet more than that of the rough zone of the anterior leaflet or the posterior leaflet. This systolic pattern in such patients differs from that associated with mitral valve prolapse.  相似文献   
2.
Effects of glycyrrhizin on immune-mediated cytotoxicity   总被引:10,自引:0,他引:10  
Intravenous administration of glycyrrhizin is known to decrease elevated plasma transaminase levels in patients with chronic viral hepatitis, in which immune-mediated cytotoxicity by cytotoxic T lymphocytes and tumour necrosis factor (TNF)-α is considered to play an important pathogenic role. However, the immunological interpretation of the transaminase-lowering action of glycyrrhizin is not known. Studies were performed to elucidate this action immunologically by assessing the effects of glycyrrhizin on immune-mediated cytotoxicity using an antigen-specific murine CD4+ T hybridoma line, which exhibits cytotoxicity against antigen-presenting cells after stimulation with specific antigen, and a murine TNF-α-sensitive fibroblast line. Glycyrrhizin inhibited the cytotoxic activity of the T cells against antigen-presenting cells and also suppressed TNF-α-induced cytotoxicity in the TNF-α-sensitive cell line in vitro. These results suggest that the decrease of elevated transaminase levels by glycyrrhizin in patients with chronic viral hepatitis is mediated in part by inhibition of immune-mediated cytotoxicity against hepatocytes.  相似文献   
3.
Abstract This study was designed to investigate the effects of 1- and 3-day (16 h/day) physically restrained or fasting on immunological and endocrine responses in CBF1 mice. The influence of stressors on these responses was evaluated using anti-sheep red blood cell plaque-forming assay, and by examining T cell subsets, thymus weight and endocrine hormone levels. The results revealed that a significant elevation of the plaque-forming cells (PFC) was found in spleen cells in 1-day restrained mice, that the PFC were conversely suppressed following 3-day physically restrained stress, and that the PFC were not affected by 1- or 3-day fasting stress. Serum levels of norepinephrine were found to be significantly increased only in 1-day physically restrained mice. No change of T cell subsets and thymus weight was found in 1-day physically restrained mice. A significant increase in serum corticosterone levels was elicited in both 1- and 3-day physically restrained mice, and 3-day fasting mice, while increased Lyt2-positive T cells and thymic atrophy were found only in 3-day physically restrained mice. These findings suggest that immune function was differentially affected by the duration and types of stressors.  相似文献   
4.
Two wide QRS tachycardias with identical morphology but different cycle lengths (CLs) developed in a 63-year-old man. Electrophysiological study demonstrated inducible atrioventricular reentrant tachycardia (AVRT) due to a concealed left posterior accessory pathway (AP), which was successfully ablated by radiofrequency application. Neither dual AV nodal pathways nor other APs were documented. Splitting of the His-bundle electrogram was shown, and programmed stimulation induced sudden prolongation of intra-hisian conduction time. These results suggest longitudinal dissociation in the His bundle may be responsible for two distinct CLs in AVRT without dualAV nodal physiology.  相似文献   
5.

Objectives

We assessed the relation between coronary plaque composition and angiographic calcification by using virtual histology intravascular ultrasound (VH‐IVUS).

Background

The plaque vulnerability according to angiographic calcification is unclear.

Methods

Subjects were 140 consecutive patients (145 lesions) undergoing VH‐IVUS before percutaneous coronary intervention. Subjects were divided into 4 groups: no calcification group (n = 27), spotty group (n = 65) that had calcium deposits under 90° in grayscale IVUS, intermediate group (n = 37) had calcium deposits with 90° or more and under 180°, and extensive group (n = 16) had calcium deposits with 180° or more.

Results

The number of VH thin‐cap fibroatheromas in spotty group was significantly larger than no calcification group, intermediate group, and extensive group (0.66 ± 0.71 vs 0.22 ± 0.42 [P < 0.01], 0.32 ± 0.48 [P < 0.05], 0.13 ± 0.34 [P < 0.01], respectively). Spotty group without angiographic calcification had significantly larger %necrotic core than with angiographic calcification (24.5 ± 6.7% vs 19.9 ± 7.2%, P < 0.05). Intermediate group without angiographic calcification had significantly larger necrotic core area than with angiographic calcification (2.5 ± 0.9 mm2 vs 1.7 ± 0.9 mm2, P < 0.05). Extensive group with angiographic calcification had significantly larger %dense calcium than without angiographic calcification (18.3 ± 4.0% vs 13.4 ± 4.4%, P < 0.05).

Conclusions

Lesions with spotty calcification was highly vulnerable in VH‐IVUS. Spotty or intermediate plaque calcification without angiographic calcification was more vulnerable than those with angiographic calcification. Extensive plaque calcification with angiographic calcification had more dense calcium than those without angiographic calcification.
  相似文献   
6.
Human cytomegalovirus (HCMV) is one of the most important agents causing opportunistic infections in immunocompromised hosts. In this study, we examined the urinary excretion of HCMV in children with malignancy using polymerase chain reaction (PCR). Urine samples were collected from on-therapy, off-therapy patients with malignancy, and healthy controls. A simple DNA extraction method using glass powder was employed, and inhibitory effect of urine on PCR was prevented. For PCR, a pair of primers from the HCMV major immediate early gene sequence was used. Among patients who received intensive chemotherapy, 52.0% had urinary HCMV excretion after the chemotherapy course. In contrast, off-therapy patients and healthy controls showed a lower incidence of urinary HCMV excretion (20.4 and 8.7%, respectively). The incidence of HCMV urinary excretion in the on-therapy group was significantly higher than healthy controls (P < 0.05). In the on-therapy group, the total white blood cell count of the virus excreters was lower than that of non-excreters. The incidence of HCMV excretion was high in on-therapy patients. Most of the virus excreters were seropositive, so their viruria was thought to be caused by reactivation. Repeated monitoring of virus excretion by this rapid and simple method may be useful to detect HCMV infection early and to control it in such patients.  相似文献   
7.
Pyruvate dehydrogenase complex (PDHC) deficiency is known to cause congenital lactic acidosis. The case of a 9-month-old female infant with PDHC deficiency caused by a mutation in exon 11 of the pyruvate dehydrogenase (PDH) Elα gene is described. Her facial features were as follows: frontal bossing, upslanting palpebral fissures, a short upturned nose, a long philtrum and low set ears. These anomalies are characteristic not only of a malformation syndrome or chromosomal aberration, but also of PDHC deficiency. Because PDHC deficiency requires early treatment, metabolic disorders should be kept in mind in a patient with dysmorphic features. Further, she had multiple minor anomalies including bilateral inguinal herniae, an umbilical hernia and small hands and feet, which have not been described in previous reports.  相似文献   
8.
Infiltrating leucocytes are activated to generate reactive oxygen species or to produce several molecules in inflamed colonic mucosa. To clarify the phenotypical and functional properties of activating cells in colitic mucosa, 23 patients with ulcerative colitis and 13 controls were studied using a combined method for determining in situ nitroblue tetrazolium reducing activity and immunohisto-chemical characterization. Antibodies 25F9 (anti-macrophage), EG2 (anti-eosinophil cationic protein), MAC387 (anti-calprotectin, expressed by activated myeloid-histiocytes lineage), and MAC-1 (anti-CD11b) were used. The proportion of EG2, calprotectin, and CD11b-positive cells were significantly increased in inflamed mucosa. The proportion of EG2, calprotectin, and CD11b-positive cells significantly correlated with the histological degree of inflammation. Proportion of EG2-positive cells but not calprotectin nor CD11b-positive cells was significantly correlated with nitroblue tetrazolium reducing activity. Aggregated cells reducing nitroblue tetrazolium seen in severely inflamed mucosa were found to be EG2 positive. Most of the calprotectin-positive cells were 25F9 negative. In addition to activation of neutrophils and macrophages, eosinophil activation has been shown to be involved in inflamed colonic mucosa.  相似文献   
9.
T cells treated with cancer sera frequently suppressed immunoglobulinproduction by autologous lymphocytes stimulated with pokeweedmitogen. Sera from healthy individuals did not induce suppressoractivity. This suppression is not caused by TG cells (T cellsbearing receptors for the Fc portion of immunoglobulin G [IgG])interacting with immune complexes, because we used T cells depletedof TG cells. The suppressor-inducing factors were separatedinto an IgG-containing fraction and a fraction with a smallermolecular weight. IgG fractions from all sera that were positivefor anti-globoside antibody induced suppressor T cells, andelimination of the anti-globoside antibody from these IgG fractionsreduced the ability to induce suppressor T cells. T cells treatedwith rabbit anti-globoside antiserum also activated suppressorT cells. These observations indicate that the antibodies directedto the globoside antigen on suppressor T cells stimulate thesuppressor T cells, and that anti-globoside antibody in cancersera may play a role in causing immunodeficiency in cancer patients.  相似文献   
10.
This case of hepatocellular carcinoma (HCC) with alcoholic liver fibrosis, which was not associated with hepatitis viruses, was accompanied by hypoglycaemia. The immunoreactive insulin level was low and other hormonal examinations were almost normal. Immunohistochemical studies showed a high level of insulin-like growth factor II (IGF2) peptide in the HCC section and the size heterogeneity of serum IGF2 investigated by western blot revealed a large form at approximately 15 kDa. These results suggest that the HCC with alcoholic liver fibrosis produced IGF2 and that the hypoglycaemia was caused by tumour-associated IGF2.  相似文献   
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