An analysis of the relative occurrence of N-demethylation and N-oxidation in xenobiotic metabolism using structure-reactivity maps

The relative occurrence of N-demethylation and N-oxidation in a structurally diverse set of N-methyl tertiary amines was examined using structure-reactivity maps. A structure-reactivity map of the data indicated important structural features useful for predicting the relative occurrence of these reactions. A steric index which describes the degree of steric hinderance at the N-methyl reaction site is defined. A QSAR between the relative occurrence of N-demethylation and N-oxidation of N-methyl tertiary amines and the steric index was developed.

Cortical renal leiomyoma with extension to renal pelvis

We describe a case of renal leiomyoma in a 21-year-old woman who presented with flank pain and hematuria. Urographic and computed tomographic (CT) studies revealed a large right renal mass with polypoid outgrowth protruding into the renal pelvis. Cortical renal leiomyoma with this radiographic manifestation is extremely rare.

Gas-containing liver abscess: radiological findings and clinical significance

Sixty-two cases of verified gas-containing pyogenic liver abscess were reviewed to study the radiological and clinical prognostic factors. A mortality rate of 37.1% (23 cases) was observed. Among these patients, the survival time of 13 patients with alveolar gas pattern or pneumoperitoneum (6.15 +/- 7.36 days) was significantly shorter than that of the other 10 patients (17.70 +/- 13.32 days) despite immediate diagnosis and aggressive treatment. The poor radiological prognostic signs were: (1) alveolar gas pattern and pneumoperitoneum as viewed on radiographs; and (2) globular configuration, shaggy margin, alveolar internal structure, and total gas content on computed tomographic (CT) scans. High serum creatinine and glucose levels and a short time to diagnosis were the poor clinical prognostic factors. The aggressive treatment did not change the outcome. We conclude that, in addition to the clinical evaluation, meticulous radiological study of the abscess morphology should be done in cases of gas-containing liver abscess in an effort to provide further aggressive treatment for those patients with poor radiological prognostic signs.

Prevalence and characteristics of areca nut chewers among junior high school students in Changhua county, Taiwan

Some studies indicate that betel quid and its ingredients chewing can produce cell mutagenicity and tumorigenicity. In Taiwan studies, betel quid chewing is the main cause of submucous fibrosis and oral cancer. Understanding the distribution and characteristics of the areca nut chewing population is one of the first steps in the effort to prevent these oral diseases. A stratified cluster random sample of 2442 junior high school students in Changhua county, Taiwan, were surveyed for the habit of areca nut chewing. Significantly more male students chewed areca nut than female students (9.2% vs 0.9%). The proportion of students who were chewing areca nuts increased with increasing (seventh to ninth) grades. Areca nut was used by junior high school students at a higher rate in village (rural) areas as compared to town (semi-urban) and city (urban) areas (6.4%, 3.7% and 3.0%, respectively). More students in the ordinary achievement classes were chewing areca nuts than those in the high achievement classes (8.4% vs 1.6%). Areca nut chewing students tended to have users in their families. Cigarette smoking and alcohol drinking were positively associated with areca nut chewing. More than half (53.6%) of the areca nut chewing students first experimented with this habit with a family member, most often the father or grandfather.

Henoch-Schoenlein purpura due to streptokinase

The syndrome of Henoch-Schoenlein purpura developed in a 74-year-old woman after receiving streptokinase as thrombolytic therapy for an acute myocardial infarction. Renal biopsy revealed mesangial hypercellularity with deposits of IgA. Skin biopsy also revealed IgA deposition. Immunological studies showed evidence of sensitization to streptokinase. Elevated IgG, IgA, IgM, and IgE antistreptokinase antibodies were detected in the acute serum. Positive immediate skin reactivity to streptokinase was also present. Serum precipitins to streptokinase disappeared when IgA was removed from the serum. Positive staining with biotinylated streptokinase was seen in the skin in the same pattern of distribution as IgA. These findings strongly support the role of streptokinase and IgA in the pathogenesis of Henoch-Schoenlein purpura in this patient. A control group of streptococcal-infected patients showed no immune response to streptokinase. Another control group of streptokinase-treated patients, who had no untoward reaction, had elevated immunoglobulin classes and precipitins to streptokinase. However, the precipitating antibody was IgG and streptokinase skin tests were negative.

Percutaneous choledochoscopic biliary tract stone removal: experience in 645 consecutive patients

Our experience in non-operative retrieval of biliary tract stones through PTCS (percutaneous transhepatic cholangioscopy, n = 103) and POC (post-operative choledochoscopy, n = 542) plus the use of Dormia basket and EHL (electrohydraulic lithotripsy) is presented. The results of transhepatic and T-tube routes are compared, with emphasis on the technical difficulties encountered. The success rates were 96% and 97% in POC and PTCS, respectively. No mortality was related to these procedures. Intrahepatic duct angulation and stricture were the factors most often responsible for failure. Postoperative choledochoscopic stone removal is safe and the method of choice for retained biliary tract calculi, while PTCS is highly indicated for those high-risk patients with or without previous biliary surgery. POC and PTCS have, therefore, their own indications and differ in their clinical applications.

Infectivity and pathogenesis of titered dosages of simian immunodeficiency virus experimentally inoculated into longtailed macaques (Macaca fascicularis)

The 50% macaque infectious dose (MID50) and pathogenesis of uncloned simian immunodeficiency virus (isolated from a pigtailed macaque, SIVmne) was determined in longtailed macaques (Macaca fascicularis). Five pairs of macaques were inoculated with 10-fold dilutions of the virus stock, and one macaque was mock-infected. The virologic and clinical status of these macaques was monitored for up to 80 weeks. The MID50 of SIVmne was determined to be 10(2) cell culture infectious dose of the original virus stock. In order to test the infectivity and pathogenesis of an established viral dose, six additional macaques were inoculated with 10x MID50 (10(3) cell culture infectious dose) of the SIVmne. The virologic and clinical status of these macaques was monitored for 40 weeks. All of the macaques inoculated with 10x MID50 or greater became infected as evidenced by seroconversion and consistent virus isolation from peripheral blood mononuclear cells. Macaques infected with SIVmne had an initial sharp decrease in CD2, CD20, CD4, CD8, and CD4CD29 lymphocyte subsets, whereas the CD4:CD8 ratio increased. Viremic macaques developed persistent slight to moderate peripheral lymphadenopathy approximately 3 to 4 weeks after inoculation. Four macaques subsequently died of AIDS-like disease at 29, 33, 42, and 80 weeks after inoculation. Data obtained from the viral titration study and the acute infection model will aid in the development of animal trials to evaluate antiretroviral therapies and preventive vaccines against human immunodeficiency virus infection.

Effect of dosing frequency on ZDV prophylaxis in macaques infected with simian immunodeficiency virus

The effect of dosing frequency on zidovudine (ZDV) prophylaxis against simian immunodeficiency virus (SIV) infection was examined in long-tailed macaque monkeys (Macaca fascicularis). The results indicate that dosing frequency is extremely important for drug efficacy. The monkeys were divided into three groups based on dosing frequencies of 6-, 8-, or 12-h intervals. All were given a total daily dose of 100 mg/kg of ZDV. The drug was administered subcutaneously starting 24 h before SIV inoculation, and treatment continued for an additional 28 days. With the total daily dose held constant, ZDV was most therapeutic when administered at 12-h intervals, less effective at 8-h intervals, and least effective at 6-h intervals. These results indicate that early ZDV treatment based on infrequent but high dosages may increase the antiretroviral effect of the drug. These findings could serve as a model for ZDV chemoprophylaxis in humans. In cases involving accidental exposure to SIV or human immunodeficiency virus (HIV-1 or HIV-2), immediate, high-dosage therapies may be most therapeutic.

Relationship between palato-radicular grooves and localized periodontitis

A total of 404 maxillary lateral and central incisors were examined in a group of 101 individuals comprising 64 males and 37 females for the presence of palato-radicular groove (PRG). The methods used to document the presence of PRG situated at or apical to the cemento-enamel junction (CEJ) included clinical probing, flap operation and inspection with the aid of an enlarging oral mirror. PRGs were classified by location in the mesial, distal and midpalatal areas of affected teeth. The plaque index (P1I), gingival index (GI) and probing pocket depth (PPD) were recorded on the lingual aspect of the teeth examined. Those PRG with initial PPDs of > or = 4 mm and located at or apical to the CEJ were counted as PRG with PPD. The difference in the PRG location for teeth with and without PPDs was analyzed via the chi 2 test. The relationship between the presence of a PRG and the patients periodontal health and plaque accumulation were analyzed using the t-test.(ABSTRACT TRUNCATED AT 250 WORDS)

Ovarian dermoid cyst associated with tuberculosis, cystadenoma and torsion

An 87-year-old woman who had had a lower abdominal mass for 32 years underwent a laparotomy. Surgery revealed a 21-cm left ovarian dermoid cyst with torsion. Pathologic examination showed a hemorrhagic infarct due to torsion, mucinous cystadenoma and tuberculosis within the tumor. Tuberculosis was also found in the endometrium, both ovaries, oviducts and omentum. The patient's recovery was uneventful after surgery and medical treatment. The clinical manifestations of tuberculosis can vary widely. Tuberculosis of an ovarian dermoid cyst may be silent for a long period of time unless other complications occur.

Neurocutaneous melanosis associated with inferior vermian hypoplasia: MR findings

OBJECTIVE

We describe the MR findings of two cases of neurocutaneous melanosis (NCM) associated with inferior vermian hypoplasia (IVH).

MATERIALS AND METHODS

Two cases of NCM associated with IVH are presented. Both patients had congenital giant hairy nevi and multiple satellite lesions.

RESULTS

Magnetic resonance imaging revealed IVH as well as hyperintensities in the pons and the cerebellar leptomeninges on T1-weighted images. The hyperintensities may be ascribed to the T1-shortening effect of melanin. A right parietal tumor in one patient and unilateral ventriculomegaly in another patient were also depicted.

CONCLUSIONS

Magnetic resonance demonstration of the T1-shortening leptomeningeal infiltrations adds weight to the diagnosis of NCM. The implication of the concurrence of NCM and IVH is discussed.

Analysis of albumin deposits on hydroxylated siloxane films. Implications for surface treatment of medical devices

The authors have developed methods to enhance albumin binding to modified silicone rubber (SR) films. An intermediate bifunctional coupling agent, polyvinylmethyl siloxane-comethyl-1-ethanol siloxane (PVMS-CO-MES), is prepared from a cyclic tetramer, vinyl-methyl siloxane, by an oxymercuration-demercuration reaction, and cross-linked to silicone rubber under mild peroxide catalytic conditions. Free mercury on the surface was obtained under many reaction conditions and is shown to materially enhance 125I-labeled albumin binding. The mechanism most likely occurs via disulfide bond breakage, protein denaturation, and aggregation. The possible role of iodine-mercury bonds, an artefactual source, is ruled out with the aid of total internal reflectance-fluorescence measurements of the albumin adsorption rate constant. Although in situ albumin aggregation via disulfide bond breakage is a potentially attractive method for biocompatible protein gel formation, the toxicity of mercury makes the current method unfit for clinical practice.

Computed tomography of an exophytic gastric hemangioma with torsion and intratumoral hemorrhage

A case of exophytic gastric hemangioma with intratumoral bleeding due to torsion of the tumor pedicle is reported. A radiograph showed a mass without phleboliths. Computed tomography (CT) demonstrated a 14-cm mass with high densities due to hemorrhage, which was contiguous to the stomach and extended to the pelvis. The tumor showed no remarkable enhancement on post-enhanced CT due to torsion of the tumor pedicle.

Noninvasive quantification of platelet accumulation and release on indwelling venous catheters

An important element in the evaluation of biomaterials is quantification of the relationships and the sequence of events between blood elements, blood flow, and the foreign surface. We adapted a qualitative two-dimensional 111In-labeled platelet imaging method to a quantitative noninvasive analysis of platelet uptake/release kinetics for infusion catheters in a canine model. Bilateral femoral vein 6 Fr. Groshong catheters (one treated with a hydroxylated siloxane to improve albumin affinity) were monitored at femoral vein sites with a GE 400T gamma camera, interfaced with a Technicare 560 image acquisition computer. The field of view was sufficiently large that all events below the diaphragm were recorded without having to move the camera. Image acquisition time was 2.5 min; images were obtained every 5-15 min for 3 hrs. Continuous recordings were obtained from bilateral ultrasonic velocity probes, attached distal to the catheter implant sites. A 5 ml blood sample was placed in the field to permit calibration of gamma emissions per pixel in terms of labeled platelet density. Signal compensation for near field capillary perfusion was performed. The two-dimensional platelet distribution was computed and displayed. Local, time dependent platelet accumulation on the catheters and adjacent vessel walls was observed. Platelet accumulation proceeded in irregular steps during the implant period. Loss of local platelet deposits was observed. Downstream reattachment of platelet emboli was inferred from simultaneous reductions and increases in local platelet densities at two catheter positions. Platelet attachment was inversely related to vein blood velocity.(ABSTRACT TRUNCATED AT 250 WORDS)

Retroperitoneal Castleman's disease: report of two cases

Castleman's disease (angiofollicular lymph node hyperplasia) is a rare benign disorder characterized by hypervascular lymphoid hyperplasia. It usually manifests as an asymptomatic, solitary mediastinal tumor, and seldom presents as an isolated retroperitoneal mass. We report two cases of histologically proven Castleman's disease occurring in the retroperitoneum. Their computed tomographic and angiographic features are presented, and the characteristics of this condition are described. Recognition of Castleman's disease in the retroperitoneal area is helpful in avoiding massive intraoperative hemorrhage and an unnecessarily extensive operation.

Diagnostic and therapeutic interventions in post-laparoscopic cholecystectomy biliary complications

Radiological imaging and therapeutic interventions were performed in eight patients with biliary complications following laparoscopic cholecystectomy. The diagnostic approach and the outcome of the therapeutic procedures were evaluated. Complications observed were bile leakage from the cystic duct stump (n = 2); erroneous identification of the cystic duct leading to common hepatic duct transection (n = 1) and hepatic duct ligation (n = 2); liver abscess (n = 1); and retained common duct stones (n = 2). Diagnostic ultrasonography is capable of detecting the presence of abnormal fluid collection and the diameter of the common duct with or without the presence of a stone, although bile leaks and retained common duct stones can only be demonstrated by either endoscopic retrograde cholangiopancreatography or percutaneous transhepatic cholangiography. Once a bile leak had been confirmed, therapeutic endoscopic biliary stenting was successfully applied in one patient while the other received percutaneous transhepatic biliary drainage. Definitive diagnosis of retained common duct stone was established by endoscopic retrograde cholangiopancreatography, and immediate endoscopic sphincterotomy with stone extraction was performed. Follow-up radiological imaging was done to determine the effectiveness of the therapeutic procedures applied in each patient. All our patients improved clinically, and further surgical intervention was not needed.

Detection of serum antibodies in Ethiopian baboons that cross-react with SIV, HTLV-I, and type D retroviral antigens

Baboons (Papio cynocephalus) imported from Ethiopia were screened for antibodies to various primate retroviruses by immunoblotting. Antibodies that cross-reacted with SIV/Mne or with type D viral antigens were detected in approximately one-third of these animals. In addition, 20% of these baboons had antibodies that cross-reacted with HTLV-I viral antigens. These data suggest that wild-caught baboons are infected with retroviruses only partially related to known primate viral isolates.

The role of ERCP and therapeutic biliary endoscopy in laparoscopic cholecystectomy

The widespread use of laparoscopic cholecystectomy for the treatment of symptomatic gallstones has been associated with an increased use of diagnostic and therapeutic biliary endoscopy to treat common bile duct stones and postoperative complications. In 250 patients with successful laparoscopic cholecystectomy, 35 were selected for preoperative ERCP evaluation after fitting the criterion of clinical evidence with common bile duct stones (ultrasound and biochemical data). Stones were found in 16 of 35 patients (45.7%). Endoscopic sphincterotomy with stone removal was successfully carried out during the procedure. Laparoscopic cholecystectomy was performed 1 or 2 days after endoscopic sphincterotomy with good result. Only one patient without clinical evidence of common bile duct stones developed postoperative retained stone; he was successfully treated by endoscopic sphincterotomy. Three patients with postoperative bile leakage were successfully treated with endoscopic nasobiliary drainage. Diagnostic and therapeutic ERCP procedures should incorporate the newly developed method of laparoscopic cholecystectomy in order to provide a more safe and minimal invasive therapy.

Intra-amniotic inoculation of pigtailed macaque (Macaca nemestrina) fetuses with SIV and HIV-1

Six pregnant pigtailed macaques (Macaca nemestrina) were inoculated intra-amniotically (i.a.) with SIVMne. All became viremic and seroconverted; three viable offspring were SIV-positive and at autopsy showed disseminated viral infection; one of three abortuses had SIV-infected thymic macrophages. Three of five pregnant macaques inoculated i.v. and/or i.a. with HIV-1LAI became virus-positive, and four seroconverted, suggesting fetal-maternal transmission. One abortus had HIV-1-antigen in lymph nodes and brain; one infant, culture-positive at birth, died at age 11 days of disseminated HIV-1 infection.

Acute myocardial infarction and left ventricular aneurysm in a patient with normal coronary arteries

A 25-year-old young man was admitted with typical manifestations of acute myocardial infarction. Cardiac catheterization performed 2 weeks later showed a left ventricular aneurysm and normal coronary arteries. Because of the unusual clinical features, an endomyocardial biopsy was done and revealed histopathological changes of acute myocarditis. Acute myocarditis presenting as acute myocardial infarction with left ventricular aneurysm formation at the same time was never reported before. The long-term prognosis of the patient with left ventricular aneurysm caused by myocarditis still needs further observation.

Giant ectopic pelvic spleen: report of a case and review of the literature

We report a case of giant ectopic pelvic spleen combined with an accessory spleen and confirmed by liver-spleen scan, angiography, magnetic resonance imaging, and surgical findings. In various reviews of the literature, no ectopic pelvic spleen larger than this one has been reported.