Effects of naftidrofuryl oxalate, a 5HT2 antagonist, on neurotransmission and transduction systems in the gerbil hippocampus

We investigated the effects of age and naftidrofuryl oxalate (Naftidrofuryl), a 5-HT₂ antagonist, on neurotransmission and transduction systems in the gerbil hippocampus using quantitative autoradiography. [³H]Quinuclidinyl benzilate (QNB), [³H]cyclohexyl-adenosine (CHA), [³H]MK-801, and [³H]muscimol were used to label muscarinic acetylcholine, adenosine A1, N-methyl-d-aspartate (NMDA), and γ-aminobutyric acid-A (GABA_A) receptors, respectively. [³H]PN200-110 labeled L-type Ca²⁺ channels. [³H]Forskolin, [³H]cyclic adenosine monophosphate (cAMP), [³H]phorbol 12,13-dibutyrate (PDBu), and [³H]inositol 1,4,5-triphosphate (IP₃) were used to label adenylate cyclase, cAMP-dependent protein kinase, protein kinase C (PKC), and IP₃ receptors, respectively. Approximately 20% reductions in [³H]QNB, [³H]forskolin, and [³H]PDBu binding were observed in the hippocampus of 9-month-old gerbils in comparison with 5-week-old gerbils. Treatment with Naftidrofuryl (10 mg/kg, i.p., once a day for 7 days) ameliorated these reductions. No changes were found in [³H]CHA, [³H]MK-801, [³H]muscimol, [³H]PN200-110, [³H]cAMP, and [³H]IP₃ binding. The results suggest that Naftidrofuryl may have beneficial effects on the age-related alterations in signal transmission and transduction systems in the brain. Because the acetylcholine system, adenylate cyclase, and PKC are considered to be involved in learning and memory processes, the result may have clinical implications.     

Clinical and manometric evaluation of anorectal function following low anterior resection with low anastomotic line using an EEA™ stapler for rectal cancer

Anorectal function was evaluated in eight patients who had low anterior resection of the rectum with a low anastomotic line, using an EEA^™ stapler, with determination of function based on periodic manometric studies and clinical symptoms. Immediately following surgery all patients suffered from frequent bowel actions and soiling. These symptoms improved with time and most patients could enjoy almost normal daily life by the sixth postoperative month. One month after surgery, anal canal resting pressure and maximum squeeze pressure were significantly reduced and rectoanal inhibitory reflex was absent; neither showed a distinct tendency to improve thereafter. Rectal sensation and reservoir capacity, which also were seriously impaired, recovered satisfactorily by the time of the six-month examination. This suggests that an improvement of clinical symptoms following this operation is dependent upon the recovery of reservoir capacity and sensation of the neorectum, and that this operative procedure is a functionally acceptable option for low rectal cancer.     

Diuretic and hypotensive actions of torasemide in hypertensive models of rat

The diuretic and the antihypertensive actions of torasemide were examined in renal and genetic hypertensive rats and compared to the effects of furosemide. Oral administration of torasemide (1 and 3 mg/kg) elicited a dose-dependent increase in the excretion of urine and electrolytes and elevated the urinary Na/K ratio in both renal and genetic hypertensive rats. Torasemide and furosemide had a similar maximum diuretic effect in the normotensive Wistar rat and the spontaneously hypertensive rat (SHR). However, the diuretic activity of furosemide was weaker in the renal hypertensive rat (RHR). Torasemide showed approximately 30 times greater diuretic potency than furosemide. Torasemide and furosemide demonstrated hypotensive action in hypertensive rat models, but not in the normotensive Wistar rat. Especially in the RHR, torasemide exhibited a more potent hypotensive action than furosemide. These results show that the diuretic and antihypertensive activities of torasemide are effective in various rat models of hypertension, while the diuretic activity of furosemide is weak in certain hypertensive rat models. © 1992 Wiley-Liss, Inc.     

Prosthetic valve endocarditis due to candida albicans treated successfully with medical treatment alone

Prosthetic valve endocarditis (PVE) caused by Candida species is associated with high morbidity and mortality. A combination of surgical resection and antifungal drug therapy is the golden standard for treatment, yet surgical intervention is not possible in all cases of Candida PVE. We report a case of PVE due to Candida albicans cured by medical treatment alone. This case suggests that, in some instances, Candida PVE can be managed medically with antifungal therapy. Such a conservative approach should be applied with caution and necessitates very close follow-up on a long-term basis.     

A case of congenital supratentorial tumor: Atypical teratoid/rhabdoid tumor or primitive neuroectodermal tumor?

Two embryonal CNS tumors, atypical teratoid/rabdoid tumor (AT/RT) and primitive neuroectodermal tumor (PNET), may be confused with each other and misdiagnosed. Here we report an infant with a congenital supratentorial tumor, which was detected by fetal MRI at 37 weeks gestation. On routine histological examination, the tumor was composed mainly of small undifferentiated cells, among which many rhabdoid cells and occasional sickle‐shaped embracing cells were observed. No mesenchymal or epithelial areas were evident. Our impression was that the tumor was an atypical example of AT/RT. Immunohistochemically, almost all the tumor cells were strongly positive for vimentin. However, epithelial membrane antigen was notably negative, and most of the tumor cell nuclei were clearly positive for INI1. In addition, many tumor cells were positive for neurofilament protein. There were also occasional small areas containing many tumor cells positive for glial fibrillary acidic protein. Finally, a diagnosis of PNET, with a rhabdoid phenotype and expression of neuronal and glial markers, was made. In the present case, application of INI1 immunostaining was very helpful for distinguishing PNET from AT/RT.     

Anaplastic astrocytoma with eosinophilic granular cells

A 68‐year‐old man, who had no remarkable past medical history, was referred to a hospital because of disorientation and right‐sided hemiparesis. On magnetic resonance imaging, a contrast‐enhanced tumor in the left frontal lobe with perifocal edema was noted. He underwent left frontal lobectomy. Microscopic examination revealed infiltrative atypical astrocytes showing increased cellularity, distinct nuclear atypia, and many mitotic figures, while microvascular proliferation and necrosis were absent. Thus, the tumor was histologically diagnosed as anaplastic astrocytoma. It was of note that cytoplasmic eosinophilic granules were observed in approximately 25% of neoplastic cells. The granules were positively immunostained with anti‐αB‐crystallin antibody, and the other histochemical and immunohistochemical results also corresponded to Rosenthal fibers. The MIB‐1 labeling index of the highest area of the tumor was 22%, while that of granular cells was 2.1%. An ultrastructural study revealed amorphous electron‐dense structures attached to intermediate filament bundles, compatible with Rosenthal fibers. Such structures are relatively common in oligodendroglial tumors; however, they are extremely rare in astrocytic tumors. Fluorescence in situ hybridization targeted against chromosome 1 failed to demonstrate allelic loss of the short arm. The present case should also be discriminated from granular cell astrocytoma. We review related literature and discuss the significance of granules in gliomas.     

Blood-brain barrier dysfunction in Binswanger’s disease; an immunohistochemical study

Binswanger’s disease is pathologically characterized by a combination of diffuse cerebrovascular white matter lesions and lacunar infarcts in the basal ganglia and white matter. Although a blood-brain barrier (BBB) dysfunction has been implicated in the pathogenesis of these white matter (WM) lesions, few authors have addressed this problem. In the present study, we describe BBB dysfunction and its regional differences in the brains of Binswanger’s disease patients. Twelve brains from Binswanger’s disease patients (group III) were examined and compared with those from five patients with non-neurological disease (group I) and five cortical infarct patients without significant WM lesions (group II). Immunohistochemistry was performed for glial fibrillary acidic protein and vimentin as astroglial cell markers, and for immunoglobulins, complements and fibrinogen as extravasated serum protein markers. The grading scores for IgG extravasation were significantly higher in group III as compared to group I, in both the periventricular WM and the subcortical WM (P < 0.01). In group III, the scores in the periventricular WM and subcortical WM were significantly higher than in the subcortical U fibers and cerebral cortex (P < 0.01 for the periventricular WM; P < 0.001 for the subcortical WM), respectively. Clasmatodendritic astroglia, which had swollen cell bodies and large cytoplasmic vacuoles with disintegrated processes, incorporated the serum components IgG, IgM, C3d, C1q and fibrinogen, both in the periventricular WM and subcortical WM in 5 out of 12 (42%) Binswanger’s disease brains. These results indicate that WM lesions in Binswanger’s disease are accompanied by BBB dysfunction, although it remains uncertain whether BBB dysfunction is secondary to either chronic cerebral ischemia or arterial hypertension. Received: 25 April 1997 / Revised, accepted: 21 July 1997