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N Ogawa  Y H Sora  M Saito  T Shimazu 《Brain research》1988,451(1-2):115-118
The effects of hypothalamic hormones and electrolytic lesioning of the ventromedial hypothalamic nuclei (VMH) on histidyl-proline diketopiperazine (cyclo(His-Pro] binding in the rat liver were studied. VMH-lesioning markedly decreased cyclo(His-Pro) binding in the liver. Scatchard analysis revealed that the loss of cyclo(His-Pro) binding induced by VMH lesioning was due to a decrease in the number and affinity of binding sites. Somatostatin (SS) administration decreased cyclo(His-Pro) binding. The SS-induced changes in cyclo(His-Pro) binding were due to changes in the binding affinity. On the other hand, the administration of TRH or LH-RH did not affect cyclo(His-Pro) binding in the liver, although cyclo(His-Pro) has been proposed to be a metabolite of TRH. These findings suggest that the hypothalamus may regulate the cyclo(His-Pro) binding sites in the liver probably by controlling pancreatic SS secretion, since a VMH-lesion is reported to cause hypersecretion of pancreatic SS.  相似文献   
3.
The aim of this study is to evaluate in vivo the effect of branched chain amino acid (BCAA). Experimentally, hepatic energy production and protein synthetic rate were measured in gastrectomized rat which was infused BCAA postoperatively. Clinically, following indices were examined in prospectively randomized patients who underwent abdominal operation and were administered with conventional total parenteral nutrition keeping Calorie/N ratio about 150, including nitrogen balance, urinary 3-methylhistidine, retinol binding protein, B lymphocyte percentage and lymphocyte blastogenesis by phytohemagglutinin. Furthermore, plasma BCAA with their keto-analog level, Factor XIII and opsonic activity were determined in another group of patients who received full strength load of BCAA immediately after subtotal or total gastrectomy, in a controlled prospective randomized double-blinded manner. Results obtained from above mentioned measurements exhibited significant improvement by the administration of BCAA. From these findings, it is suggested that BCAA sustains energy-protein metabolism, supports immunocompetence and promotes wound healing under moderately stressed condition where catabolic response is physiologically compensated.  相似文献   
4.
Effects of sympathetic denervation on biochemical and morphological changes of brown adipose tissue (BAT) were studied in rats after severing 5 intercostal nerve bundles that enter the unilateral interscapular BAT, the contralateral BAT being used as the control. Four weeks after denervation, there was no appreciable change in BAT weight or its DNA and protein contents, whereas the triglyceride content was increased significantly. However, the rate of fatty acid synthesis was decreased to about half the rate in controls. The denervated BAT was much paler than controls and contained lots of adipocytes filled with large lipid droplets, some of which were unilocular. The results are discussed with reference to changes in BAT seen after bilateral lesions of the ventromedial hypothalamus.  相似文献   
5.
The influence of experimentally induced hepatic dysfunction on the pharmacokinetics of Cyclosporine A (CsA) was determined in dogs. The pharmacokinetics of oral (PO) and intravenous (IV) CsA were studied before and after 70 per cent hepatectomy or complete bile duct ligation (CBDL). Changes in liver function were monitored by serial measurements of serum bilirubin, and by the maximum removal rate (Rmax) and plasma disappearance rate (ICG-K) of indocyanine green (ICG). Concentrations of CsA in whole blood were measured by HPLC. Seventy per cent hepatectomy caused significant liver dysfunction: the ICG-Rmax decreased by 47.7±7.1 per cent (mean±SD) and the ICG-K decreased by 61.3±9.7 per cent during the first week after hepatectomy. At the same time, the systemic clearance (CLs) of IV-CsA decreased by 43.9±8.2 per cent, the area under the concentration curve (AUC) of IV-CsA increased by 35.4±20.8 per cent and the bioavailability of CsA decreased by 26.4±14.8 per cent. CBDL also induced significant liver dysfunction: the ICG-Rmax decreased by 39.1±12.8 per cent and the ICG-K decreased by 65.6±3.6 per cent in the second week after the operation. During the same period, the AUC of PO-CsA decreased by 69.9±10.7 per cent and the bioavailability of CsA also decreased markedly by 73.9±15.6 per cent. These data indicate that hepatic impairment significantly influences the pharmacokinetics of CsA, not only by the changes in intestinal absorption, but also by those in hepatic, metabolism. Dose adjustment is therefore necessary in the presence of hepatic dysfunction in order to maintain an adequate blood concentration of CsA without causing side effects. This research was performed in the Department of Surgery, University of Pittsburgh Health Center, University of Pittsburgh, USA  相似文献   
6.
M Kondo  H Matsuda  S Kureya  A Shimazu 《Spine》1989,14(8):862-866
To clarify the pathophysiology of intermittent claudication in 37 patients with lumbar spinal stenosis, neural function was evaluated by examining somatosensory evoked potentials (stress-SEPs), and nerve action potentials (stress-NAPs) before and after walking stress. It was shown preoperatively that the stress-SEPs became abnormal immediately after walking in 31 of 37 patients. In seven of nine operated patients, the assessment clearly shows that SEPs had reverted to normal after surgery. The present method is noninvasive, simple in technique, painless, and safe, a procedure therefore that is useful as the initial step in the diagnosis and treatment of patients with lumbar canal stenosis. It also may help to differentiate neurogenic from vascular intermittent claudication.  相似文献   
7.
Macroscopic diagnosis for lymph node metastases was compared with histopathological diagnosis in 444 patients with carcinoma of the esophagus, stomach, colon, thyroid and breast. The former indicated lymph node metastases in 181 patients. In all of them, none or less than five node metastases were proven by routine histopathological diagnosis. Detailed histological study revealed lymph node metastases in 25 out of 263 patients with macroscopically negative nodes, the rate of false negative being 9.5 per cent. The study also demonstrated no lymph node metastases in 51 of 181 patients with macroscopically positive nodes. Three additional specimens were obtained from originally examined 693 lymph nodes and reexamined microscopically in these 51 patients. Involvement by cancer cells was detected in 9 nodes (1.3 per cent) in 8 patients. Metastases were found from additional specimens in 7 of 9 nodes, indicating that metastatic carcinoma had been overlooked in the remaining two nodes. Additional specimens or embedding-techniques were recommended in such cases as macroscopic metastases were strongly suspected or lymph vessel invasions were remarkable. In 24 patients with esophageal cancer, one to one correspondence was available in the analysis of macroscopic diagnosis. Seventy-eight out of 108 involved nodes were macroscopically judged as involved (sensitivity; 72.2 per cent), and 1166 out of 1260 nodes without macroscopical metastases were judged as cancer-free (specificity; 92.5 per cent). Overestimation of macroscopic diagnosis was due to thickened capsule, fibrosis, inflammation and enlargement in size more than 10 mm in diameter of the nodes. Underestimation was observed in case of nodes with metastatic area less than one-third and with smaller size less than 5mm in diameter.  相似文献   
8.
Thrombotic microangiopathy (TMA) may develop after living donor liver transplantation (LDLT), but the mechanism is not fully understood. We retrospectively analyzed all patients undergoing LDLT at our center, including TMA patients, to elucidate the clinical characteristics and presentation and to determine which patients have a higher risk of occurrence of TMA. In all, 57 adult patients were reviewed after LDLT at our institution. TMA was diagnosed by sudden and severe thrombocytopenia, followed by hemolytic anemia with fractionated erythrocytes in the blood smear. Clinical features were compared between the TMA group and the non-TMA group. Of the 57 patients, 4 were diagnosed with posttransplantation TMA. ABO blood group (ABO)-incompatibility, cyclophosphamide (CPA), and recipient blood group (type O) were closely correlated with the occurrence of TMA. Thrombocytopenia appeared 1 to 5 days before hemolytic anemia. Coagulative function markers stayed at the same level after TMA, while marked elevation was shown in fibrinolytic function markers such as plasminogen activator inhibitor type 1 (PAI-1). TMA occurred at a higher prevalence in ABO-incompatible graft recipients. Additional factors associated with ABO-incompatible transplantation, such as an overdose of immunosuppressants, may affect the likelihood of TMA. Sudden and severe thrombocytopenia presented before hemolytic anemia and the serum levels of PAI-1 correlated well with the clinical course of TMA. In conclusion, early recognition of thrombocytopenia and elevation of PAI-1 is crucial to diagnose TMA especially in ABO-incompatible LDLT.  相似文献   
9.
We present a suspicious case of central neurosarcoidosis that presented with progressive gait disturbance probably caused by central vestibular dysfunction. And this case showed elevated level of angiotensin converting enzyme (ACE) in the cerebrospinal fluid, compared with the average level of two cases with acute inflammatory demyelinating neuropathy syndrome and four cases of multiple sclerosis. A 33-year-old man was admitted to our hospital with chief complaint of a gait disturbance that had appeared 3 years prior to the admission. And the symptom had exacerbated in these 3 months. Except for the gait disturbance and positive Romberg's sign, no neurological abnormality was detected. The findings of the cerebrospinal fluid test supported the diagnosis of meningitis. An increased level of angiotensine converting enzyme was detected when compared with our previous samplings from two cases of Guillain Barré syndrome and four cases of multiple sclerosis. With T1 weighted imaging of brain MRI, a high intensity lesion with gadolinium enhancement was identified in the central gray matter of the midbrain. Scan of the chest confirmed bilateral hilar lymphadenopathy. Based on these findings and the patient's clinical course, central neurosarcoidosis was suspected. The patient's symptoms improved dramatically after the administration of corticosteroid. The enhancement of the central gray matter ameliorated, and the ACE level of the CSF was decreased to the level of the demyelinating disorders.  相似文献   
10.
Rat cartilage tissue was found to produce two types of proteoglycan monomers distinguished by density gradient centrifugation under dissociative condition and with different molecular size (PG I and PG II) as observed in cultured rabbit costal chondrocyte and human cartilaginous tissues. The incorporation of 35S-sulfate and distribution of the molecular size of proteoglycan (PG) were studied to determine the differentiated phenotypes of chondrocyte in adjuvant induced arthritis of rats. The cartilaginous tissue from the acute inflammatory phase shows a low incorporation of 35S-sulfate into PGs but produce the same hydrodynamic size as that of the control. After that acute phase the incorporation recovered suggesting of a repair phase. But in the chronic phase both the incorporation and the produced hydrodynamic size of PGs were severely alternated. With our method this paper shows the drastic alternation about the cartilaginous properties of rat chondrocytes under these circumstances.  相似文献   
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