Increase in choroidal blood flow in rabbits with endothelin-1 induced transient complete obstruction of retinal vessels

Background: In a previous paper, we reported that retinal blood flow (RBF) ceased immediately after injection of 1 nmol endothelin-1 (ET-1) and no recovery of RBF was detected for at least 50 min. In this study, we confirmed the same duration of RBF cessation and measured choroidal blood flow (CBF) for 180 min. Methods: We measured CBF in a rabbit model of transient complete obstruction of retinal vessels induced by intravitreal injection of a high dose of ET-1, using the hydrogen clearance method. We also investigated the effects of intravitreal injection of ET-1 on intraocular pressure (IOP), blood pressure, pulse rate and blood gases. Results: CBF was significantly greater in the ET-1-injected eyes than in the control eyes 40–130 min after injection of ET-1 (P < 0.05). The maximal CBF ratio in the ET-1-injected eyes was 128 ± 7.4% at 40 min. CBF decreased to the pre-injection level at 140 min after the injection of ET-1. There was no significant change in blood pressure, pulse rate and blood gases throughout this experiment, and there was no significant difference in IOP between ET-1-injected eyes and control eyes. Conclusion: It seems likely that the increase in CBF resulted from some local mechanisms of control that compensated for the decrease in RBF induced by intravitreal injection of ET-1. This model may be useful for investigation of the regulatory system of intraocular circulation, including endothelin receptors.     

Fluorescence automatic cell sorter and immunohistochemical investigation of CD68-positive cells in meningioma

Infiltration of brain neoplasms by mononuclear cells including monocytes/macrophages has attracted little attention since they have marked morphological heterogeneity. Twenty-seven meningiomas were studied by anti-CD68 antibody-gated flow cytometry and by immunohistochemical analysis using the anti-CD68 antibodies. Flow cytometric analysis divided cells contained within tumor tissues into CD68-positive and -negative cells. In addition, eight gliomas, eight metastatic brain tumor, and 12 pituitary adenomas were investigated in the same way to compare meningiomas. The mean contents of CD68-positive cells were 24.0±3.7% in meningiomas, 4.4±1.4% in gliomas, 9.5±3.9% in metastatic brain tumors, and 4.5±1.8% in pituitary adenomas. Immunohistochemically, CD68-positive cells showed significant heterogeneity and were detected as round, rod-shaped, ameboid and ramified cells in meningiomas. Although the infiltrated mononuclear cells in gliomas have been investigated to some degree and showed that they express cytokines and/or growth factors, these infiltrated cells in meningioma have barely been studied. The CD68-positive cells detected in this study are likely to be monocytes, macrophages and microglias, and are presumed to be in various functional stages and to play important roles in growth regulation in meningioma.     

Neurovascular developmental interaction: a specific form of vascular maldevelopment in the malformed brain

The process of the development of the intracranial vessels was studied by means of immunohistochemical analysis of factor VIII in normal and exencephalic chick fetuses. The results revealed that the development of blood vessels in exencephalic brain was far advanced beyond the norm, with intense immunoreactivity to factor VIII on postincubation day 16 exceeding that on day 21 in normal controls. Compared with results regarding the direction of the overgrowth in the neuronal maturation process in the previous study using the chick exencephaly model, the findings of overmatured blood vessels were compatible with NSE- and somatostatin-positive elements that appeared especially in the overgrowth foci. The results of the present study suggested the pathogenic development of the area cerebrovasculosa in the neural placode as a phenomenon consequent upon hypervascularization in response to neuronal overgrowth, as seen in human cases of exencephaly or anencephaly. We emphasize the significance of this specific phenomenon in the development of the fetal central nervous system, namely neurovascular developmental interaction.     

Serine protease inhibitors prevent alcoholic liver injury]

The hepatotoxic effects of alcohol have been described in detail, but factors responsible for its hepatotoxicity have only partially characterized. It now appears that Kupffer cell derived TNF-alpha participates in several aspects of alcoholic liver injury. On the other hand, protease inhibitors have been used successfully for treatment of intractable diseases in which TNF-alpha is involved in the pathogenesis, including ulcerative colitis and Crohn's disease. Here, we will review new evidence for the proposal that serine protease inhibitors prevents alcoholic liver injury via mechanisms dependent on Kupffer cell derived TNF-alpha.     

Gender difference in alcoholic liver injury]

Gender differences of alcoholic liver injury have been described previously, but mechanisms have only partially characterized. For example, it is known that females develop alcoholic liver injury more rapidly and to a greater extent than males. It now appears that estrogen participates in several aspects of this phenomenon. On the other hand, attention has been directed towards the effect of ethanol ingestion on Kupffer cell function, which is stimulated by gut-derived endotoxins via mechanisms dependent on increased gut permeability and the possible relationship between Kupffer cell and alcohol-induced liver injury.     

Nevoid Basal cell carcinoma syndrome with medulloblastoma and meningioma--case report

A 35-year-old man presented with a rare case of nevoid basal cell carcinoma syndrome, or Gorlin's syndrome, associated with both medulloblastoma and meningioma, manifesting as visual field constriction due to multiple parasellar tumors. He had undergone resection of a medulloblastoma at the age of 1 year 9 months, followed by adjunctive irradiation with a total dose of 40 Gy. He presented with multiple subcutaneous nodules on his face and neck. Histological examination of biopsy specimens established the diagnosis of nevoid basal cell carcinoma syndrome. Tuberculum sellae meningioma was removed through a craniotomy, and his symptoms improved. Meningioma is known to occur in the field of therapeutic irradiation, so chemotherapy may be a better option for medulloblastoma associated with nevoid basal cell carcinoma syndrome.     

A case of acute renal failure after exercise with renal hypouricemia demonstrated compound heterozygous mutations of uric acid transporter 1

Familial renal hypouricemia is a hereditary disease characterized by extraordinary high renal uric acid (UA) clearance and is associated with acute renal failure (ARF). A 17-year-old Japanese male developed ARF after anerobic exercise. Renal function improved completely after approximately 2 weeks of hydration treatment. After remission, hypouricemia became evident (1.0 mg/dL) from the initial level of UA (4.8 mg/dL) and fractional excretion of uric acid (FEUA) was >50%. His parents showed normal levels of UA and FEUA. Polymerase chain reaction of a urate anion exchanger known to regulate UA level [SLC22A12 gene: UA transporter 1 (URAT1)] demonstrated compound heterozygous mutations (Q297X and R90H). Thus, we describe a Japanese male with hypouricemia complicated by anerobic exercise-induced ARF, with definite demonstration of a genetic abnormality in the responsible gene, URAT1.     

Role of Intraoperative Cholangiography in Patients Whose Biliary Tree Was Evaluated Preoperatively by Magnetic Resonance Cholangiopancreatography

Background

Routine performance of intraoperative cholangiography (IOC) during cholecystectomy is controversial. The aim of this study was to evaluate the role of IOC during cholecystectomy in addition to preoperative magnetic resonance cholangiopancreatography (MRCP) in our institution over a 12-year period.

Methods

A total of 425 consecutive patients who underwent IOC during cholecystectomy were included in this study. MRCP was performed preoperatively for bile duct evaluation in all patients. When common bile duct (CBD) stones were detected, they were removed endoscopically before the operation. We estimated the results of IOC in terms of the success rate, the detection rate of anatomic abnormality of the biliary system, and the incidence of residual CBD stones.

Results

MRCP preoperatively identified 6 (1.4?%) patients with abnormal biliary systems and 56 with CBD stones, which were endoscopically removed. The success rate of IOC was 93.8?% (399/425). Abnormalities of the biliary system were detected in 12 patients (12/399, 3.0?%) and CBD stones in 8 (8/399, 2.0?%). Of the eight patients with stones, seven had been examined by endoscopy preoperatively and found to have CBD stones. The detection rate of bile duct stones in patients with preoperative endoscopic removal of CBD stones (7/56, 12.5?%) was significantly higher than those with CBD stones first detected during IOC (1/365, 0.3?%) (p?<?0.01). Moreover, no residual CBD stones were detected in patients who were operated on within fewer than 12?days from endoscopic treatment to the operation.

Conclusions

IOC is indicated even after preoperative sphincterotomy for CBD stones. In our study, it resulted in a 12.5?% incidence of persistent stones after sphincterotomy. IOC plays an additional role in detecting CBD stones and in revealing abnormalities of the biliary tree in patients whose biliary tree was preoperatively evaluated by MRCP.