Difficulty in diagnosing chronic meningitis caused by capsule-deficient Cryptococcus neoformans

We report a case of chronic meningitis due to capsule-deficient Cryptococcus neoformans which could not be diagnosed by routine morphological and immunological cerebrospinal fluid (CSF) examination. Repeated CSF examination and culture did not disclose the fungal body, and the cryptococcal antigen tests were always negative. Culture of ventricular fluid showed non-encapsulated cultured cells which were stained positively by indirect immunofluorescence using diluted sera from another patient diagnosed with cryptococcal meningitis. Inoculation of dispersed colonies into mice resulted in encapsulated C neoformans. It is important to suspect capsule-deficient C neoformans when the conventional diagnostic approaches fail to identify the organism or antigens.     

Measurement of cerebral reserve capacity using acetazolamide loading xenon CT CBF before carotid endarterectomy

BACKGROUND AND PURPOSE: Brain swelling and/or hemorrhage can occur after carotid endarterectomy. This phenomenon is called the hyperperfusion syndrome. Several factors contribute to this syndrome. One is reperfusion in a maximally dilated vessel which means disappearance of cerebral reserve capacity (CRC). The aim of the study was to determine whether CRC measurement was useful for intraoperative and postoperative management of carotid endarterectomy. PATIENTS AND METHODS: We studied 64 cases (male 53, female 11), 49-79 years. CRC was measured preoperatively using acetazolamide loading Xenon CT CBF examination (XeCT). Hypothermia (34-35 C) was induced during surgery in a patient with no CRC. Anesthesia was maintained the night after surgery and the systolic blood pressure was controlled below 120 mmHg. RESULTS: CRC was absent in 10 patients. Postoperative CT did not reveal any hemorrhage or brain swelling. One patient experienced a transient restless state. DISCUSSION: and conclusions: Cerebral hyperperfusion syndrome has been reported in 0.3 approximately 6.0% of patients following carotid endarterectomy (vs 1.6% in our study without hemorrhage or brain swelling). These data suggest that information on CRC could be useful for selection and perioperative management of patients during carotid endarterectomy.     

Protecting RNA in fixed tissue: an alternative method for LCM users

RNA degradation is a major drawback in most common fixation protocols in techniques that require both RNA integrity and preserved morphology, such as laser capture microdissection (LCM) followed by RT-PCR. Moreover, RNA isolation kits especially developed for LCM samples are very expensive. Our aim was to determine an easy protocol that ideally must provide an acceptable morphology, allow proper laser capture of selected cells and improve RNA yield and quality. In this study, retinas were dissected, briefly incubated in a RNA preservative and fixed in 2% paraformaldehyde before being cut on a cryostat. LCM was carried out in retinal sections for immediate RNA isolation, by using TRIzol common protocol with minor modifications. Real-time PCR was performed next in order to compare availability of RNA from samples submitted to different protocols. The use of the RNA preservative followed by a fast fixation did not jeopardize tissue morphology, allowing microdissection of selected cells, combined to minor modifications in usual RNA isolation procedures, significantly improved RNA yield and quality. Furthermore, only LCM samples submitted to our protocol provided amplifiable mRNA, as determined by real-time PCR. Taken together, the combination of the described procedures resulted in a reliable alternative for LCM users.     

Decreased cell-mediated immune status in colorectal cancer patients with hepatic metastasis

BACKGROUND/AIMS: Depression of cell-mediated immunity frequently accompanies solid tumor malignancy, and appears to be worsened as the disease progresses. In this study, we investigated cell-mediated immune status in colorectal cancer patients. METHODOLOGY: Interleukin-2 (IL-2) productivity by phytohemagglutinin (PHA)-stimulated non-adherent peripheral blood mononuclear cells (PBMC), and prostaglandin E2 (PGE2) productivity by LPS-stimulated adherent PBMC were investigated in colorectal cancer patients with hepatic metastasis (n=20) and without hepatic metastasis (n=20), and in non-malignant disease controls (n=20). Percentages of peripheral blood T-cell subsets and NK activity were also investigated. RESULTS: In the colorectal cancer patients with hepatic metastasis IL-2 productivity was significantly decreased, compared with the controls. However, the percentages of T-cell subsets and NK activity were not significantly different among the groups. Meanwhile, PGE2 productivity in the patients with hepatic metastasis was significantly increased, compared with the other groups, and was significantly correlated with the hepatic tumor load. CONCLUSIONS: Tumor-bearing state, especially metastasis to the liver, may influence immune status of the patient. For evaluating cellular immunity status, cytokine productivity by activated lymphocytes and monocytes may be a more sensitive marker rather than other conventional immunological parameters, and may also provide useful information for immune intervention in the treatment of patients from this point of view.     

Castleman's disease arising from the accessory spleen: ultrasonography, computed tomography, and magnetic resonance imaging findings

Castleman's disease is a rare lymphoproliferative disorder of unknown etiology. To our knowledge, Castleman's disease arising from the accessory spleen has not been reported in the literature. We report the case of localized Castleman's disease arising from the accessory spleen in a 34-year-old woman and discuss the characteristic findings of ultrasonography (US), computed tomography (CT), and magnetic resonance (MR) imaging.     

Unexpected abnormal extra-cardiac mediastinal accumulation of technetium-99m-tetrofosmin in patient with acute pericarditis

A 58-year old woman had felt some chest pains on effort for several days. She was admitted to the emergency room with severe and refractory chest pain after exercise. Electrocardiogram showed marked ST-segment elevations in II, III, aVF and V1-6 electrodes. Echocardiogram revealed neither wall motion asynergy in the left ventricle nor abnormal pericardial effusion. Chest X-ray showed normal findings, and mild elevation of C-reactive protein was observed in the blood chemistry data. Her chest pain was relieved by nitroglycerin administration. Emergent technetium-99m-tetrofosmin myocardial imaging did not show any abnormal perfusion in the left ventricle. However, an abnormal extra-cardiac mediastinal accumulation was detected in the planar image. Contrast-enhanced chest CT scanning also demonstrated an inhomogeneously enhanced tumor in the anterior superior mediastinum. The tumor was surgically removed and was finally diagnosed as an invasive thymoma. Technetium-99m-tetrofosmin scintigraphy happened to provide useful information for diagnosing acute pericarditis with mediastinal tumor.     

Regulation of aminopeptidase A expression in cervical carcinoma: role of tumor-stromal interaction and vascular endothelial growth factor

We previously demonstrated that aminopeptidase A (APA), a membrane-bound metallopeptidase degrading bioactive peptides such as angiotensin II (Ang II), is expressed in neoplastic lesions of the uterine cervix, and that its expression is upregulated as the lesion progresses from cervical intraepithelial neoplasms (CIN) toward invasive squamous cell carcinomas (SCC). The present study investigated the regulatory mechanisms involved in APA expression and its potential role in cervical carcinoma. Immunohistochemical staining in high-grade CIN and SCC tissues showed that APA was strongly expressed at the edge of lesions adjacent to cervical stromal cells. Fluorescence-activated cell sorting analysis demonstrated that cell surface APA expression was extremely low in three human SCC cell lines, SiHa, TCS and CaSki, under basal conditions. However, both contact and noncontact cocultures with human cervical fibroblasts resulted in the induction of APA expression in these SCC cells. APA expression was also induced in vivo when TCS cells were subcutaneously inoculated into nude mice. Furthermore, APA expression and enzymatic activity were enhanced by addition of the conditioned medium (CM) from fibroblast culture, but not by heat-treated CM. Among the various cytokines tested, vascular endothelial growth factor (VEGF) significantly increased APA activity, and induction of APA by the fibroblast CM was partly inhibited by anti-VEGF neutralizing antibody. Finally, APA cDNA-transfected APA-overexpressing TCS cells significantly reduced the Ang II-induced cell invasion ability as compared with parental or control vector-transfected TCS cells, although there was no significant difference in cellular proliferation among them. These results suggested the importance of tumor-stromal interaction for the regulation of APA expression in the microenvironment of cervical carcinoma and the potential role for this peptidase in regulating tumor invasion through inactivation of Ang II activity.