Protective effect of adenosine against neuronal injury induced by middle cerebral artery occlusion in rats as evidenced by diffusion-weighted imaging

In the present study, adenosine, an inhibitory neuromodulator, was studied in male Wistar rats subjected to 2 h of transient middle cerebral artery (MCA) occlusion. Adenosine (500 mg/kg ip) was administered twice-once at the time of MCA occlusion and again at the time of reperfusion-and evaluated for its protective effect by using diffusion-weighted imaging (DWI) (30 min after reperfusion). After the DWI experiments, one group of animals was euthanized 2 h after reperfusion for the estimation of oxidative stress markers, while in another group, neurological deficit was assessed 24 h after MCA occlusion. In the adenosine-treated group, percent hemispheric lesion area (%HLA) in DWI was significantly attenuated (11.7+/-5.2) as compared to vehicle-treated group (21.4+/-4.7). The level of malondialdehyde (MDA) (301.8+/-22 nmol/g wet tissue) in the adenosine-treated group was significantly decreased as compared to that in the vehicle-treated MCA-occluded rats (420+/-20 nmol/g wet tissue). An insignificant change was observed in the levels of glutathione in both the vehicle-treated MCA-occluded and the adenosine-treated groups. The neurological deficit was significantly improved in the adenosine-treated group (1.8+/-0.06) as compared to the vehicle-treated (2.9+/-0.38) group. This is the first study to demonstrate the effectiveness of adenosine using DWI in the MCA-occluded rats.     

Tick mouth parts occlusive vasculopathy: a localized cryoglobulinemic vasculitic response

BACKGROUND: The histologic hallmark of most arthropod bite reactions is a deep, wedge-shaped perivascular and interstitial infiltrate comprising lymphocytes, neutrophils, and eosinophils. METHODS: We present a case series of six patients in whom tick bite reactions, when examined microscopically, were found to mimic mixed cryoglobulinemic vasculitis. RESULTS: Though different in histology, clinically these lesions were indistinguishable from typical tick bite reactions. CONCLUSION: As five of our six biopsy specimens were found to still harbor retained tick parts, it is possible that the actual retention of tick parts was involved in evoking this localized cryoprecipitate reaction.     

Clinico-pathological profile of pediatric lymphadenopathy

Objective : To study the clinico-pathological profile of significant pediatric peripheral lymphadenopathy and to arrive at an etiological diagnosis.Methods : Prospective study in a tertiary care hospital setting. One hundred consecutive children reporting to pediatric OPD from 1 January 1995 to 31 December 1998, aged 1 month to 12 years were studied.Results : The commonest aetiology diagnosed was tubercular lymphadenitis in 35% cases, followed by chronic tonsillopharyngitis in 15% cases. Lymphomas, AIDS and infectious mononucleosis constituted 3,2 and 1 cases each. Aetiology could not be ascertained in 44 (44%) children even after detailed haematological, microbiological, radiological and serological investigations. FNAC’s sensitivity and specificity as compared to ’gold standard of excision lymph node biopsy was 94% and 100% respectively.Conclusion : Tubercular lymphadenitis was the commonest treatable entity of significant pediatric peripheral lymphadenopathy. A majority of the cases even after thorough evaluation, remained undiagnosed. FNAC as a diagnostic modality is almost as sensitive and as specific as excision lymph node biopsy when an adequate aspirate is examined by expert eyes.     

Tuberculosis of paranasal sinuses

Nasal tuberculosis is very rare but much rarer is tuberculosis of paranasal sinuses. It involves especially the maxillary sinus and is usually unilateral. We report an unusual case of tuberculosis of frontal and maxillary sinus in a 68 years old male, who presented with a swelling above left medial canthus, with no other eye or nasal complaints. Clinical and radiological findings on our initial evaluation suggested that the patient had left frontal mucocoele with bilateral maxillary haziness. Diagnosis was established on FNAC report and subsequent Ziehl — Neelsen staining of nasal swabs and tuberculin skin test. Later chest x-ray examination was suggestive of pulmonary tuberculosis, which was the primary cause. Patient responded well to antituberculosis drug therapy.     

Phenotypic diversity of intrahepatic and extrahepatic cholangiocarcinoma on aspiration cytology and core needle biopsy: case series and review of the literature

BACKGROUND: Cholangiocarcinoma (CC) represents approximately 10% of primary liver malignancies and can mimic metastatic adenocarcinoma. METHODS: The authors retrospectively reviewed the cytopathology files at the University of Texas Medical Branch to identify patients who were diagnosed with intrahepatic or extrahepatic CC by aspiration cytology between 1995 and 2004. Brush cytology specimens of extrahepatic CC were excluded. All diagnoses were confirmed as CC by clinical, imaging, and histopathologic findings and by chart review. RESULTS: Cytopathology files from 13 patients with CC diagnosed by FNA were retrieved. The male:female ratio was 5:8, and the patients ranged in age from 29 years to 74 years (mean age, 59 years). In 12 of 13 patients, aspirates were obtained by ultrasound guidance; and, in 1 patient, computed tomography guidance was used. Three patients had aspirates only, 10 patients also had core biopsies, and 1 patient had cell block preparations. The phenotypic distribution of CC according to the World Health Organization (WHO) histologic classification was 9 adenocarcinoma (intrahepatic), not otherwise specified (NOS) (69%); 2 gastric foveolar type (extrahepatic) CCs (15%); 1 intestinal type (extrahepatic) CC (8%); and 1 sarcomatous/spindle cell type (intrahepatic) CC (8%). One adenocarcinoma, NOS was well differentiated CC with bland tubular architecture, and one was pleomorphic. Ancillary histochemical and immunochemical stains were performed on 5 of 13 specimens, which included 4 core biopsies and 1 aspirate with Mucicarmine positivity (3 specimens), carcinoembryonic antigen positivity (3 specimens), and a cytokeratin 7 (CK7)-positive/CK20-negative pattern (2 specimens). The 1 sarcomatous/spindle cell type CC was chromogranin-negative and low molecular weight keratin (cell adhesion molecule 5.2)-positive, which excluded metastatic carcinoid. CONCLUSIONS: Classification of intrahepatic and extrahepatic CC in aspiration cytology specimens was achieved in a reliable manner concordant with the WHO histologic classification. Special types of CC with bland nuclear features posed a diagnostic challenge on cytologic evaluation, particularly the well differentiated CC with tubular architecture and the gastric foveolar type CC with mucin-producing tumor cells. The addition of core biopsy and/or ancillary studies, such as histochemical and immunochemical stains, were helpful in reaching the correct diagnosis.     

Leiomyosarcoma of the inferior vena cava: a case report and review of literature

Tumors of the inferior vena cava are rare, and most of these are leiomyosarcomas. They are most frequent in the sixth decade of life, with a female predominance. We present a 45-year-old male patient with a tumor involving the entire extent of the inferior vena cava. Computerized tomography revealed a heterogeneously enhancing mass with marked expansion of the inferior vena cava with extraluminal extension. Computerized tomography--guided biopsy of the extraluminal component showed features of a fasciculated spindle cell tumor positive for vimentin, smooth muscle actin, and calponin and negative for S-100 antigen. We discuss the clinical presentation imaging findings and review the literature.