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71.
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   
72.
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   
73.
The effects of unloading or inotropic agent in 22 patients with dilated cardiomyopathy were assessed in terms of optimal coupling between the ventricle and arterial system. In 13 patients (group A), lower body negative pressure (LBNP) was applied to reduce preload and nitroprusside was used to decrease afterload. In 9 patients (group B), dobutamine was used to enhance inotropic state. In all patients, the direct arterial pressure was simultaneously recorded with left ventricular echocardiogram as the pressure was elevated by phenylephrine. The left ventricular contractile properties were defined by the slope (Ees) of the end-systolic pressure-volume relation. The arterial system properties were expressed by the slope (Ea) of the end-systolic pressure-stroke volume relation. When the Ea/Ees ratio ranged from 0.5 to 1.0, both external work and mechanical efficiency are nearly maximized. In group A, baseline ventricular-load coupling was characterized by an increase in the Ea/Ees ratio (1.96 +/- 1.08) where the heart could maximize neither external work nor mechanical efficiency. Ea/Ees significantly fell to 1.45 +/- 0.77 with nitroprusside, while increasing to 2.37 +/- 1.17 during LBNP. In group B, Ea/Ees was decreased from 1.43 +/- to 0.82 +/- 0.47 with dobutamine. It is concluded that reduction in afterload rather than preload, or augmentation of contractility could restore optimal ventricular-load coupling in patients with severe cardiac dysfunction.  相似文献   
74.
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   
75.
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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77.

Introduction

Bariatric surgery is recognized as an effective treatment for type 2 diabetes mellitus, but data on its efficacy for type 1 diabetes mellitus, especially slowly progressive insulin‐dependent diabetes mellitus, are limited.

Methods

We investigated five Japanese patients with slowly progressive insulin‐dependent diabetes mellitus who underwent bariatric surgery at our center.

Results

Five morbidly obese glutamic acid decarboxylase antibody‐positive diabetic patients underwent two different types of bariatric surgery. The mean titer of anti‐glutamic acid decarboxylase antibody was 4.6 U/mL, and the mean preoperative bodyweight and BMI were 113 kg and 39.6 kg/m2, respectively. The mean hemoglobin A1c was 8.4%. The mean fasting serum C‐peptide was 5.0 ng/mL. Laparoscopic sleeve gastrectomy was performed in two patients, while laparoscopic sleeve gastrectomy with duodenojejunal bypass was performed in three patients. At one year after surgery, the mean bodyweight and BMI significantly dropped, and the mean percentage of excess weight loss was 96.4%. The mean hemoglobin A1c was 5.7%. This favorable trend was maintained at mid‐term.

Conclusion

Bariatric surgery for morbidly obese patients with anti‐glutamic acid decarboxylase antibody–positive type 1 diabetes mellitus, especially slow progressive autoimmune diabetes, seemed effective in achieving mid‐term glycemic control. Longer follow‐up with a larger number of patients, as well as validation with more advanced patients with slowly progressive insulin‐dependent diabetes mellitus, will be needed.
  相似文献   
78.
Recently, exercise-induced spastic coronary artery occlusion at the site of moderate stenosis, which Prinzmetal’s angina or cardiac syndrome X does not cover, was reported. Multi-modality imaging is important for the diagnosis of coronary artery disease with a complex ischemic mechanism. However, the previous report did not include findings from intracoronary imaging at the site of moderate coronary stenosis. We report a case of exercise-induced vasospastic angina at the site of moderate stenosis, where multi-modality imaging, including exercise stress echocardiography and intravascular ultrasound, was utilized to make a definitive diagnosis and investigate underlying causes.  相似文献   
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