Anxiolytic effect of hepatocyte growth factor infused into rat brain

BACKGROUND: Hepatocyte growth factor (HGF) has the capacity to selectively direct thalamocortical projections into an intermediate target, the pallidum, and eventually to their final cortical destination. HGF may have a role in the mediation of anxiety. Very little is known about other central behavioral effects of HGF. OBJECTIVE: Our aim was to determine what effect HGF has on anxiety in rats. METHODS: HGF was infused at a constant rate into cerebral lateral ventricles and its effect on anxiety in rats was monitored. RESULTS: In the elevated plus maze test and the black and white box test, HGF administration caused all indicators of anxiety to increase. No significant effect on general locomotor activity was seen. CONCLUSION: HGF infusion into the brain produces an anxiolytic effect.     

Frontotemporal dementia with co-occurrence of astrocytic plaques and tufted astrocytes, and severe degeneration of the cerebral white matter: a variant of corticobasal degeneration?

We report two patients who exhibited frontotemporal dementia (FTD) with unusual neuropathological features. The ages of the patients at death were 65 and 67 years, the disease durations were 6 and 5 years, and the clinical diagnoses were Picks disease and corticobasal degeneration (CBD), respectively. At autopsy, both cases exhibited neuropathological findings compatible with those of CBD, including atrophy of the frontal and parietal lobes, neuronal loss and gliosis in the cortical and subcortical regions, and presence of cortical ballooned neurons and astrocytic plaques (APs). In both cases, immunoblotting of insoluble tau exhibited the pattern of selective accumulation of four-repeat tau, a finding that is also compatible with CBD. However, severe degeneration was evident in the frontal and parietal white matter in both cases. Moreover, a striking finding was the widespread presence in the affected cortex of tufted astrocytes (TAs), which are characteristic of progressive supranuclear palsy (PSP). Neither co-occurrence of APs and TAs nor severe degeneration of the cerebral white matter is a feature of either CBD or PSP. No mutations were found in the tau gene in either case. In conclusion, the possibility that these two cases represent a new neuropathological phenotype of non-familial FTD rather than simply a variant of CBD cannot be completely excluded.     

Transthyretin-related familial amyloidotic polyneuropathy

Transthyretin-related familial amyloidotic polyneuropathy (FAP) is a fatal hereditary amyloidosis. Until 20 years ago, FAP was thought to be restricted to endemic occurrence in certain areas. However, owing to progress in biochemical and molecular genetic analyses, FAP is now believed to occur worldwide. As of today, reports of about 100 different points of single or double mutations, or a deletion in the transthyretin gene, have been published, and several different phenotypes of FAP have been documented, even for the same mutation in the transthyretin gene. We present herein the current clinicopathological, biochemical, molecular genetic, and epidemiological aspects of transthyretin-related FAP, and we introduce a new diagnostic procedure for the disease.     

Reversed operation of glutamate transporter GLT-1 is crucial to the development of preconditioning-induced ischemic tolerance of neurons in neuron/astrocyte co-cultures

Sublethal ischemia leads to increased tolerance against subsequent prolonged cerebral ischemia in vivo. In the present study, we investigated the roles of the astrocytic glutamate (Glu) transporter GLT-1 in preconditioning (PC)-induced neuronal ischemic tolerance in cortical neuron/astrocyte co-cultures. Ischemia in vitro was simulated by subjecting cultures to both oxygen and glucose deprivation (OGD). A sublethal OGD (PC) increased the survival rate of neurons significantly when cultures were exposed to a lethal OGD 24 h later. The extracellular concentration of Glu increased significantly during PC, and treatment with an inhibitor of N-methyl-D-actetate (NMDA) receptors significantly reversed the PC-induced ischemic tolerance of neurons, suggesting that the increase in extracellular concentration of Glu during PC was critical to the development of PC-induced neuronal ischemic tolerance via the activation of NMDA receptors. Treatment with a GLT-1 blocker during PC suppressed this increase in Glu significantly, and antagonized the PC-induced neuronal ischemic tolerance. This study suggested that the reversed operation of GLT-1 was crucial to the development of neuronal ischemic tolerance.     

Differential effects of N-peptidyl-O-acyl hydroxylamines on dynorphin-induced antinociception in the mouse capsaicin test

In the capsaicin test, intrathecal (i.t.) dynorphins are antinociceptive. Cysteine protease inhibitors such as p-hydroxymercuribenzoate (PHMB) given i.t. augment and prolong their activity. The effect of two novel cysteine protease inhibitors, N-peptidyl-O-acyl hydroxylamines, on the antinociception induced by i.t. administered dynorphin A or dynorphin B has been investigated. When administered i.t. 5 min before the injection of capsaicin (800 ng) into the plantar surface of the hindpaw, dynorphin A (62.5-1000 pmol) or dynorphin B (0.5-4 nmol) produced a dose-dependent and significant antinociceptive effect. The effect of dynorphin A (1 nmol) and dynorphin B (4 nmol) disappeared completely within 180 and 60 min, respectively. PHMB (2 nmol) and Boc-Tyr-Gly-NHO-Bz (BYG-Bz) (2 nmol) co-administered with dynorphin A or dynorphin B significantly prolonged antinociception induced by both. On the other hand, Z-Phe-Phe-NHO-Bz (ZFF-Bz) (1 and 2 nmol) only prolonged antinociception induced by dynorphin A. The results suggest that Z-Phe-Phe-NHO-Bz is an inhibitor of cysteine proteases preferring cleavage of dynorphin A, with less specificity towards dynorphin B in the mouse spinal cord.     

Insulin independence after living-donor distal pancreatectomy and islet allotransplantation

Rising demand for islet transplantation will lead to severe donor shortage in the near future, especially in countries where cadaveric organ donation is scarce. We undertook a successful transplantation of living-donor islets for unstable diabetes. The recipient was a 27-year-old woman who had had brittle, insulin-dependent diabetes mellitus for 12 years. The donor, who was a healthy 56-year-old woman and mother of the recipient, underwent a distal pancreatectomy. After isolation, 408 114 islet equivalents were transplanted immediately. The transplants functioned immediately and the recipient became insulin-independent 22 days after the operation. The donor had no complications and both women showed healthy glucose tolerance. Transplantation of living-donor islets from the distal pancreas can be sufficient to reverse brittle diabetes.     

Current concepts of vascular calcification

Vascular calcification, such as coronary and aortic calcification, is a significant feature of vascular pathology. Two distinct forms of vascular calcification are well recognized. One is medial calcification, which occurs between the cell layers of smooth muscle cells, and is related to aging, diabetes and chronic renal failure. The other is atherosclerotic calcification, which occurs in the intima during the development of atheromatous disease. It has been shown that statins inhibit the progression of calcification in the aortic valve and the coronary artery. We have found that statins inhibit calcification of human aortic smooth muscle cells, which is induced by incubating the cells in high-phosphate medium. We also found that this is mediated by inhibiting cellular apoptosis, an essential mechanism for calcification, not by inhibiting inorganic phosphate (Pi) uptake by sodium-dependent phosphate cotransporter (NPC). Besides apoptosis and Pi uptake, such proteins as osteoprotegerin (OPG), matrix Gla protein (MGP), Klotho, fetuin-A, and apoE have been shown to negatively affect vascular calcification. Many previous reports suggest that vascular calcification appears to be regulated by promoting factors, such as Pi, apoptosis, modified LDL, advanced glycation end products, oxidative stress, vitaminD3, glucocorticoid, cbfa-1, osteopontin, and inhibitory factors, such as OPG, MGP, Klotho, fetuin-A, PTH/PTHrP, pyrophosphate, statins, and bisphosphonates. The precise mechanism of vascular calcification is of interest.     

Detectability of lesions in multiplanar reformation (MPR) of the lung

PURPOSE: To evaluate the diagnostic ability of multiplanar reformation (MPR) images of the lung in comparison with thin-section source CT images. MATERIALS AND METHODS: MPR images were reconstructed for 79 patients with suspected pulmonary disease. Slice thicknesses of source images were 2 mm in 24, 1 mm in 30, and 0.5 mm in 25 cases. The presence of centrilobular nodules, emphysema, bronchiectasis, ground-glass opacity (GGO), consolidation, interstitial thickening, and pulmonary nodule was evaluated on thin-section source images by an experienced chest radiologist to establish gold standards and then subsequently assessed on the MPR images independently by two radiologists. The sensitivity, specificity, and accuracy of each finding were calculated regarding the results of thin-section source images as the gold standards. Accuracy for the detection of findings was also statistically compared among the three groups of different source slice thicknesses using Fisher's exact test. RESULTS: Accuracy for the detection of findings was significantly less (p < 0.05) in 2 mm slice MPR for centrilobular nodule, GGO, and interstitial thickening than in 1 mm or 0.5 mm slice MPR. No statistically significant difference was observed for any of the findings between 0.5 mm and 1 mm slice MPR. Rates of sensitivity, specificity, and accuracy of the MPR images for detection of the findings were 89-100%, 73-95%, and 84-95%, respectively. CONCLUSION: In comparison with thin-section source images, MPR images are comparably sensitive but not as specific for the detection of findings. When producing MPR images, the slice thickness of source images should be less than 2 mm.