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OBJECTIVE: The novel vaso-constricting 31-amino acid-length endothelin-1 [ET-1(1-31)] is selectively produced by human mast cell chymase via its action on big ET-1. However, the pathological role of ET-1(1-31) in atherosclerosis remains unclear. The aim of this study was to clarify vasoconstrictive response and expression of ET-1(1-31) in atherosclerotic aorta. METHODS AND RESULTS: Syrian golden hamster, was used for preparing the atherosclerotic models by the administration of a high cholesterol diet (HC), treatment with the nitric oxide synthase inhibitor (Nomega-nitro-L-arginine methylester, L-NAME) alone, or both (HC and L-NAME) for 40 weeks. Early atherosclerosis was observed in the case of HC or L-NAME alone treatments respectively and severe atherosclerosis was observed in the case of combined HC and L-NAME treatment. Vasoconstriction induced by ET-1(1-31) was not altered by the atherosclerotic changes, but the expression pattern of ET-1(1-31) was different at each stage of the atherosclerotic aorta. ET-1(1-31) was observed rarely in normal aortas or in early atherosclerotic lesions, but ET-1(1-31) expression was dramatically increased in aortic neointima and adventitia in a state of atherosclerosis with severe inflammation. CONCLUSION: ET-1(1-31) might play in a role of promoting atherosclerosis, and especially be involved in inflammatory mediation during the progression of atherosclerosis.  相似文献   
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The P wave of the magnetocardiogram (MCG) was investigated in normal subjects and patients with mitral stenosis to determine its characteristics in normal conditions and left atrial overloading (LAO) and to analyze atrial activation by a magnetic field. In normal subjects, the MCG P wave was negative in left parasternal sites and positive in right lower sternal sites. The current source deduced from the MCG pattern and isomagnetic map was directed inferiorly and to the left through the entire phase of atrial activation, suggesting that in most normal cases the P wave reflects right atrial activity. In patients with mitral stenosis, a negative-positive biphasic P wave was seen more frequently than in normal subjects in left parasternal sites (p less than 0.005). In the late phase of atrial activation, the current source deduced from the isomagnetic map was shifted superiorly and to the left, suggesting an increased leftward force due to LAO. The MCG was similar in sensitivity to the ECG, for diagnosis of LAO, but in a few cases LAO could be detected from the MCG but not the ECG. These findings suggest that the MCG is clinically useful for diagnosis of LAO.  相似文献   
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OBJECTIVE: In the early phase after transmural myocardial infarction (MI), the infarcted myocardium undergoes replacement by scar tissue, which is essential for preserving the structural integrity of the infarcted tissue. Transforming growth factor (TGF)-beta1, which is known as a fibrotic cytokine, plays a pivotal role in the reparative fibrosis after MI. It is reported that granulocyte colony-stimulating factor (G-CSF) can accelerate wound healing. The aim of our study was to investigate the effect of G-CSF on early ventricular expansion after MI. METHODS: MI was induced by ligation of the left coronary artery in male Wistar rats. G-CSF (20 microg/kg/day, MI-GCSF) or saline (MI-saline) was injected subcutaneously 3 h after MI and every 24 h thereafter for 7 days. Hemodynamic and echocardiographic studies were performed at 14 days. Expression of TGF-beta1 and procollagen type I and type III mRNA in both the infarcted and noninfarcted areas was studied by quantitative RT-PCR at 1, 3, 7, and 14 days after MI. Histological studies were performed at 7 days. RESULTS: MI-GCSF had higher LV max dP/dt, lower LV end-diastolic pressure, and smaller LV end-diastolic and end-systolic dimensions compared to MI-saline. Infarct size was not different between MI-GCSF and MI-saline. Expression of TGF-beta1 mRNA in the infarcted area at 3 days was significantly higher in MI-GCSF than in MI-saline. Expression of procollagen type I and type III mRNA in the infarcted area at 3 days was higher in MI-GCSF compared to MI-saline, and the peak mRNA levels were earlier in MI-GCSF. In the noninfarcted area, there was no difference in TGF-beta1 mRNA expression between MI-GCSF and MI-saline. Histologically, collagen accumulation in the infarcted area at 7 days was more prominent in MI-GCSF than in MI-saline. CONCLUSION: G-CSF treatment improves early post-infarct ventricular expansion through promotion of reparative collagen synthesis in the infarcted area, suggesting some beneficial effect of G-CSF on the infarct healing process.  相似文献   
66.
The contraction of muscle enhances the release of bradykinin (BK) and improves glucose uptake by the muscle. Angiotensin-converting enzyme inhibitor (ACEI) slows the breakdown of BK, thus the effect of BK is augmented in the presence of ACEI. The present study investigated whether the combination of exercise (increased production of BK) and ACEI (delay in breakdown of BK) might further improve insulin sensitivity in hypertensive patients with insulin resistance (HOMA-R>1.8). Patients were assigned either to increased walking distance (Walking group) or taking 2 mg temocapril, an ACEI, daily (ACEI group) for 8 weeks. Then both interventions were given to all patients for 8 weeks (ACEI+Walking group). Blood concentrations of triglycerides were slightly lower in the ACEI+Walking group than at baseline, although there were no significant differences in total cholesterol or high density lipoprotein-cholesterol among the 2 groups. Blood glucose was not significantly different with each treatment, but blood concentrations of insulin and HOMA-R were significantly lower in the Walking and ACEI groups compared with the Control group. The combination of walking and ACEI further lowered blood concentrations of insulin and HOMA-R, which suggests that this treatment is beneficial for hypertensive patients with insulin resistance.  相似文献   
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Introduction:Gastric varices can be present in up to 20% of patients with portal hypertension. However, a varix of the left gastroepiploic vein (LGV) is extremely rare. Surgery is required if bleeding occurs; thus, precise diagnosis is crucial. We present a successful case of preoperative diagnosis intraabdominal varix of the LGV using three-dimensional-computed tomography angiography (3D-CTA) followed by laparoscopic resection. This is the first report of a case with variant LGV. Our study demonstrates the efficacies of 3D-CTA and laparoscopic surgery for the diagnosis and safe resection of the intraabdominal varix, respectively.Patient concerns:A 74-year-old woman was referred to our department with a tumor in the abdominal cavity. On physical examination, no lumps were palpable in the upper abdomen.Diagnosis:The enhanced CT was revealed that the tumor was not enhanced in the early phase, but in the equilibrium phase. Moreover, 3D-CTA clearly revealed that the tumor was being supplied by the LGV. Thus, it was diagnosed as a variant of the LGV.Interventions:Surgical resection was performed laparoscopically as per the guidance of preoperative 3D-CTA findings. During surgery, a dark tumor was found along the gastroepiploic vessels, supplied by the LGV. The tumor was resected safely based on the preoperative information.Outcomes:Histopathological examination of the tumor showed accumulation of various vessels, but no malignant cells. Therefore, we made a final diagnosis of the tumor as an LGV varix. For follow-up, an annual CT examination was performed and after 3 years postoperation, no recurrence was observed.Conclusions:In the present case, we have achieved a successful preoperative diagnosis using 3D-CTA, and resection was safely accomplished using laparoscopy guided by preoperative anatomical information. This is the first report of an LGV variant. Appropriate management is crucial because bleeding is a catastrophic event. Therefore, imaging procedures such as 3D-CTA for diagnosis, followed by safe resection by laparoscopic surgery, are effective tools for the treatment of epiploic vein varices.  相似文献   
68.
Mutations in the PARKIN/PARK2 gene that result in loss‐of‐function of the encoded, neuroprotective E3 ubiquitin ligase Parkin cause recessive, familial early‐onset Parkinson disease. As an increasing number of rare Parkin sequence variants with unclear pathogenicity are identified, structure–function analyses will be critical to determine their disease relevance. Depending on the specific amino acids affected, several distinct pathomechanisms can result in loss of Parkin function. These include disruption of overall Parkin folding, decreased solubility, and protein aggregation. However pathogenic effects can also result from misregulation of Parkin autoinhibition and of its enzymatic functions. In addition, interference of binding to coenzymes, substrates, and adaptor proteins can affect its catalytic activity too. Herein, we have performed a comprehensive structural and functional analysis of 21 PARK2 missense mutations distributed across the individual protein domains. Using this combined approach, we were able to pinpoint some of the pathogenic mechanisms of individual sequence variants. Similar analyses will be critical in gaining a complete understanding of the complex regulations and enzymatic functions of Parkin. These studies will not only highlight the important residues, but will also help to develop novel therapeutics aimed at activating and preserving an active, neuroprotective form of Parkin.  相似文献   
69.
We classified ipsilateral breast tumor recurrences (IBTRs) based on strict pathological rules. Ninety‐six women who were surgically treated for IBTR were included. IBTRs were classified according to their origins and were distinguished based on strict pathological rules: relationship between the IBTR and the primary lumpectomy scar, surgical margin status of the primary cancer, and the presence of in situ lesions of IBTR. The prognosis of these subgroups were compared to that of new primary tumors (NP) in the narrow sense (NPn) that occurred far from the scar. Distant‐disease free survival of IBTR that occurred close to the scar with in situ lesions and a negative surgical margin of the primary cancer (NP occurred close to the scar, NPcs) was similar to that of NPn. In contrast, IBTR that occurred close to the scar without in situ lesions (true recurrence (TR) that arose from residual invasive carcinoma foci, TRinv) had significantly poorer prognosis than NPn. IBTR that occurred close to the scar with in situ lesions and a positive surgical margin of the primary cancer (TR arising from a residual in situ lesion, TRis) had more late recurrences than NPcs. Precise pathological examinations indicated four distinct IBTR subtypes with different characteristics.  相似文献   
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