Supervised Autonomous Electrosurgery via Biocompatible Near-Infrared Tissue Tracking Techniques

Autonomous robotic surgery systems aim to improve patient outcomes by leveraging the repeatability and consistency of automation and also reducing human induced errors. However, intraoperative autonomous soft tissue tracking and robot control still remains a challenge due to the lack of structure, and high deformability of such tissues. In this paper, we take advantage of biocompatible Near-Infrared (NIR) marking methods and develop a supervised autonomous 3D path planning, filtering, and control strategy for our Smart Tissue Autonomous Robot (STAR) to enable precise and consistent incisions on complex 3D soft tissues. Our experimental results on cadaver porcine tongue samples indicate that the proposed strategy reduces surface incision error and depth incision error by 40.03% and 51.5%, respectively, compared to a teleoperation strategy via da Vinci. Furthermore, compared to an autonomous path planning method with linear interpolation between the NIR markers, the proposed strategy reduces the incision depth error by 48.58% by taking advantage of 3D tissue surface information.

Interferometric focal length measurement of positive and negative lenses using a lateral-shearing cyclic path optical configuration setup and polarization phase-shifting interferometry

We present a simple interferometric focal length measurement technique for measuring the focal length of positive and negative lenses using a lateral-shearing cyclic path optical configuration (CPOC) setup and polarization phase-shifting interferometry (PPSI). The technique requires an auxiliary lens, whose focal length need not be known accurately, for generating a focused point source at its focal plane. The focal point of the test lens is adjusted to be in the vicinity of the focus of the auxiliary lens. The radii of the resulting spherical wave fronts emerging from the test lens, due to the defocus, for two different longitudinal shifted positions of the test lens are measured using the lateral-shearing CPOC setup and PPSI. Focal length of the test lens is determined from the known longitudinal shift and from the measured radii of the spherical wave fronts. Results obtained for 200.0 mm convex and 100.0 mm concave test lenses are presented.

Examination of Relationships among Organizational Characteristics and Organizational Commitment of Nurses in Western and Eastern Region of Nepal

INTRODUCTION

The objective of this study is to identify relationships between three components of organizational commitment and organizational characteristics of nurses in the western and the eastern region of Nepal.

METHODS

A self-administrated questionnaire was used to collect data from 310 nurses currently working at various hospitals in the eastern and the western region of the country. The questionnaire included three sections namely 1) personal characteristics 2) organizational characteristics and 3) organizational commitments scale. Descriptive analysis and multiple regression analysis were performed to identify significance in various relationships.

RESULTS

Out of the 240 completed questionnaires, 226 were found valid for analysis. The mean age was 27.4 years. For each depended variable affective, continuance and normative commitment, multiple regression analysis was performed with personal Characteristics and organizational characteristics as independent variables. All independent variables were found significantly related to each of the two dependent variables; affective commitment and normative commitment (R2 adjusted=0.24, p<0.01 and R2 adjusted=0.05, p<0.01 respectively). However, they were not significantly related to the continuance commitment. Both support from boss (β=0.138, p<0.05) and satisfaction with training (β=0.301, p<0.05) were found to be positive and significant with affective commitment. On the other hand, satisfaction with training (β=0.191, p<0.05) was also positive and significant with normative commitment.

CONCLUSIONS

Since both support from boss and training program were found to be positive and significant with affective commitment, hospitals must encourage supervisors to provide more assistance to the subordinate nurses. Moreover, hospitals should develop more training programs to keep nurses motivated.

Dielectric properties and emissivity of seawater at C-band microwave frequency

Microwave remote sensing applications over ocean using radar and radiometers, a precise knowledge of emissivity and reflectivity, are required. Emissivity of ocean surface is a function of the surface configuration, frequency of radiation, temperature and its dielectric properties. The emissivity of a smooth ocean surface at a particular wavelength is determined by its complex dielectric properties. In present study, laboratory measurements of complex dielectric properties, real part epsilon', and imaginary part epsilon", of surface seawater samples collected from Bay of Bengal and Arabian Sea are carried out. Measurements of these seawater samples are done at 5 GHz and 30 degrees C using an automated C-band microwave bench set up. The salinity of samples is also measured using autosalinometer. The salinity values are used to determine epsilon' and epsilon" using the Debye equations. The normal incidence emissivity and brightness temperature values for smooth sea surface are reported for surface samples. The dielectric constant epsilon' decreases and dielectric loss increases with increase in salinity at 5 GHz and 30 degrees C. At normal incidence, emissivity is almost constant for varying salinities.

Study of self-generated magnetic fields in laser produced plasmas using a three-channel polaro-interferometer

Self-generated magnetic fields produced in laser plasmas at moderate laser intensities have been measured using a three-channel polaro-interferometer. The main elements of this device are two birefringent calcite wedges placed between two crossed polarizers. Using this device, the spatial profiles of (a) the rotation angle (polarometry), (b) the electron density (interferometry), and (c) the transmitted probe beam intensity (shadowgraphy) are recorded simultaneously using a digital camera with a large format CCD in a single laser shot. Magnetic fields of 2-4 MG had been estimated in aluminum plasma at laser intensities ~10(13) W/cm(2). It is also possible to use this device in other configurations to get time resolved information.

Gaucher's disease

Gaucher's disease is the most common group of lysosomal storage disorders caused by defective activity of an enzyme beta-glucosidase leading to accumulation of glucocerebroside in cells of macrophage lineage. Accumulation of glucosylceramide in tissues leads to multisystem organ involvement viz. liver, spleen, bone marrow, lungs and central nervous system. Serum beta=glucosidase levels <15% of mean normal activity confirms the diagnosis, enzyme replacement being the only definitive treatment. We report a clinical case of a 21 year male with Gaucher's disease. To the best of our knowledge only six cases of Gaucher's disease have been reported from India so far.

Prevalence of nonalcoholic fatty liver disease in patients with type 2 diabetes mellitus

OBJECTIVES

Nonalcoholic fatty liver disease (NAFLD) is commonly associated with type 2 diabetes mellitus (DM) though its prevalence is not well studied. We conducted a prospective study of prevalence and risk factors of NAFLD in patients with type 2 diabetes.

RESEARCH DESIGN AND METHODS

204 type 2 DM patients attending an out-patient diabetic clinic underwent abdominal sonography. Ninty of 127 patients with fatty infiltration on ultrasound consented for liver biopsy, clinical and biochemical workup.

RESULTS

Eighty seven percent had NAFLD on histology with 62.6% steatohepatitis and 37.3% fibrosis. Age, duration of diabetes mellitus, degree of glycemic control, body mass index, waist circumference, family history of diabetes mellitus, did not predict the presence or severity of NAFLD or fibrosis. Serum alanine aminostranferase (ALT) and alkaline phosphatase levels, though within normal limits, were significantly higher in patients with steatohepatitis. Prevalence of NASH increased with increase in the components of the metabolic syndrome. Serum AST/ALT ratio were also significantly higher (p-0.049) in patients with severe fibrosis. All patients with severe fibrosis had metabolic syndrome.

CONCLUSIONS

Prevalence of NAFLD and NASH in our cohort of type 2 DM patients is high and increases with multiple components of metabolic syndrome. NASH and advanced fibrosis can occur in diabetic patients without any symptoms, signs or routine laboratory test abnormalities.

An unrealistic drift in assay on anhydrous basis towards content limit

The assay on anhydrous basis is a mathematically derived value from an experimental results of assay and water content tests. The results of assay and water content tests are determined, separately, on as-is basis. The industry-accepted formula for assay on anhydrous basis = (assay on as-is basis×100)/(100-%water). Statistically, the two variables involved in accepted formula are assay on as-is basis and water to obtain assay on anhydrous basis. The experimental errors associated with these two variables propagate in assay on anhydrous basis. The error propagates either in constructive or destructive mode. The constructive mode of error propagation is combination of positive error of assay on as-is basis and positive error of water or negative error of assay on as-is basis and negative error of water. The constructive mode of error propagation has more impact on assay on anhydrous basis values and its confidence interval. The destructive mode of error propagation is combination of a positive error of assay on as-is basis and a negative error of water or vice versa. The destructive mode of error propagation has lesser impact on assay on anhydrous basis values and its confidence interval in comparison to the constructive mode of error propagation. In accepted formula said above, the constructive or destructive error propagation causes unrealistic drift of assay on anhydrous basis towards either lower or higher side of content limit of substance. The risk of rejection of pharmaceutical use substance is higher based on assay test results that results are calculated from industry-accepted formula. The purpose of the study is to propose an alternative formula to overcome limitations of accepted formula and justify the propagation of errors in realistic way. We have given three examples of pharmaceutical use substances to emphasise the above proposition. The proposed formula for assay on anhydrous basis= (assay on as-is basis×Φ)/(Φ-%water) in which Φ is sum of experimental results of assay and water content tests experimentally determined, separately, on as-is basis.

Protective effect of Tinospora cordifolia, Phyllanthus emblica and their combination against antitubercular drugs induced hepatic damage: an experimental study

This study investigated the hepatoprotective effect of two Indian medicinal plants Tinospora cordifolia (Tc), Phyllanthus emblica (Pe), and their combination, in a rat model of isoniazid, rifampicin and pyrazinamide induced hepatic damage. Hepatic damage was assessed using a composite score assigned to histopathological findings of degeneration, necrosis and fibrosis. The antituberculosis treatment (ATT), when given for 90 days, induced significant degeneration and necrosis (score: 7.5; p < 0.01 vs vehicle) associated with morphological changes. However, no change was found in the serum bilirubin and liver enzymes. Co-administration of silymarin (positive control, 50 mg/kg) with ATT protected against necrosis (score: 1.5; p < 0.001 vs ATT). Tc (100 mg/kg) showed a reduction in liver damage (score: 6.5), which was not statistically significant. On the other hand, Pe (300 mg/kg) prevented the necrotic changes to a significant extent (grade 1.0; p < 0.05; score [corrected] 5.5). Combination of Tc and Pe in their therapeutic doses (1:3) significantly prevented the necrosis (score: 3.5; p < 0.001 vs ATT). Similar effects were seen even when the doses were halved and were comparable to the silymarin group. Thus, this study proves the synergistic protective effects exerted by the combination of Tc and Pe when co-administered with ATT.

Electroconvulsive therapy in drug resistant neuroleptic malignant syndrome

We report a case of a 20 years female referred to us with a history of a brief psychotic episode for which she was given inj. Haloperidol. The patient presented in an unconscious state with high grade fever. The diagnosis was kept as neuroleptic malignant syndrome after ruling out other possibilities. The patient did not respond to Bromocriptine and Dantrolene. With the recent evidence of electroconvulsive therapy being useful in these patients, we went ahead with the same. We present this case to share our experience of the excellent response of neuroleptic malignant syndrome to electroconvulsive therapy.

Fluorescence properties of Nd3+-doped tellurite glasses

The compositional and concentration dependence of luminescence of the (4)F(3/2)-->(4)I(J) (J=13/2, 11/2 and 9/2) transitions in four Nd(3+)-doped tellurite based glasses has been studied. The free-ion energy levels obtained for 60TeO(2)+39ZnO(2)+1.0Nd(2)O(3) (TZN10) glass have been analysed using the free-ion Hamiltonian model and compared with similar results obtained for Nd(3+):glass systems. The absorption spectrum of TZN10 glass has been analysed using the Judd-Ofelt theory. Relatively longer decay rates have been obtained for Nd(3+)-doped phosphotellurite glasses. The emission characteristics of the (4)F(3/2)-->(4)I(11/2) transition, of the Nd(3+):TZN10 glass, are found to be comparable to those obtained for Nd(3+):phosphate laser glasses. The non-exponential shape of the emission decay curves for the (4)F(3/2)-->(4)I(11/2) transition is attributed to the presence of energy transfer processes between the Nd(3+) ions.

Semi-automated imaging system to quantitate estrogen and progesterone receptor immunoreactivity in human breast cancer

A semi-automated imaging system is described to quantitate estrogen and progesterone receptor immunoreactivity in human breast cancer. The system works for any conventional method of image acquisition using microscopic slides that have been processed for immunohistochemical analysis of the estrogen receptor and progesterone receptor. Estrogen receptor and progesterone receptor immunohistochemical staining produce colorimetric differences in nuclear staining that conventionally have been interpreted manually by pathologists and expressed as percentage of positive tumoral nuclei. The estrogen receptor and progesterone receptor status of human breast cancer represent important prognostic and predictive markers of human breast cancer that dictate therapeutic decisions but their subjective interpretation result in interobserver, intraobserver and fatigue variability. Subjective measurements are traditionally limited to a determination of percentage of tumoral nuclei that show positive immunoreactivity. To address these limitations, imaging algorithms utilizing both colorimetric (RGB) as well as intensity (gray scale) determinations were used to analyze pixels of the acquired image. Image acquisition utilized either scanner or microscope with attached digital or analogue camera capable of producing images with a resolution of 20 pixels /10 mu. Areas of each image were screened and the area of interest richest in tumour cells manually selected for image processing. Images were processed initially by JPG conversion of SVS scanned virtual slides or direct JPG photomicrograph capture. Following image acquisition, images were screened for quality, enhanced and processed. The algorithm-based values for estrogen receptor and progesterone receptor percentage nuclear positivity both strongly correlated with the subjective measurements (intraclass correlation: 0.77; 95% confidence interval: 0.59, 0.95) yet exhibited no interobserver, intraobserver or fatigue variability. In addition the algorithms provided measurements of nuclear estrogen receptor and progesterone receptor staining intensity (mean, mode and median staining intensity of positive staining nuclei), parameters that subjective review could not assess. Other semi-automated image analysis systems have been used to measure estrogen receptor and progesterone receptor immunoreactivity but these either have required proprietary hardware or have been based on luminosity differences alone. By contrast our algorithms were independent of proprietary hardware and were based on not just luminosity and colour but also many other imaging features including epithelial pattern recognition and nuclear morphology. These features provide a more accurate, versatile and robust imaging analysis platform that can be fully automated in the near future. Because of all these properties, our semi-automated imaging system 'adds value' as a means of measuring these important nuclear biomarkers of human breast cancer.

Utilization of antihepatocyte clone OCH1E5 (Hep Par 1) in histological evaluation of liver tumors

Diagnosis of hepatocellular carcinoma (HCC) is not always easy on simple hematoxylin and eosin (H&E) stain. The diagnostic problems arise when tumor shows pseudoglandular, pleomorphic or clear cell differentiation. Various tumors markers have been described with varying sensitivity and specificity. Monoclonal antibody Hep Par 1 (OCH1E5) which is specific for hepatocytes offers great help in separation of these tumors. The aim of the present study was to determine utility of Hep Par 1 (OCH1E5) in differentiating HCC from metastatic tumors and cholangiocarcinoma. Total of 62 cases of liver tumors obtained from biopsies, resected or autopsy specimens were included in the study. Slides having representative sections were subjected to immunohistochemistry with monoclonal antibody Hep Par 1 (Dako Corp) using avidin biotin technique with primary antibody dilution of 1:40. Adjacent nontumorous hepatocytes were taken as positive control. Slides were examined by experienced pathologist without any information of clinical or H&E diagnosis. Cases were considered positive for Hep Par 1 if tumor cells showed cytoplasmic brown colored granules. The intensity and distribution (diffuse/ focal) of immunoreactivity was noted. Subsequently immunohistochemistry results were correlated with histology and clinical diagnosis. Hep Par 1 antibody was positive in 26 (42 %) and negative in 36 (58 %) liver tumors. On correlating with H&E sections, out of 26 positive cases, 25 (89.2%) were HCC and one was the case of metastasis of mucin secreting adenocarcinoma. From 36 tumors with negative staining 3 were cases of HCC, 27 metastatic adenocarcinomas and 6 cholangiocarcinomas. Only one case of liver metastasis of mucin secreting adenocarcinoma showed positivity. None of the cases of cholangiocarcinoma showed positivity for Hep Par 1. The three HCCs which did not take up staining for Hep Par 1 were 2 cases of moderately differentiated HCC having pseudoglandular pattern and a case of well differentiated HCC with trabecular arrangement. In 11(44%) cases staining was diffuse while in 14 (56%) it was focal but intense. Hep Par 1 is a useful marker in differentiating HCC from metastaic tumors and cholangiocarcinoma with sensitivity and specificity of 89 % and 97 % respectively and positive predictive value of 96 %. However one should be aware of limitations of immunohistochemistry.

Luminescence and optical absorption properties of Nd(3+) ions in K-Mg-Al phosphate and fluorophosphate glasses

Absorption and emission properties and fluorescence lifetimes for the [Formula: see text] transition of Nd(3+) ions embedded in P(2)O(5)-K(2)O-MgO-Al(2)O(3) (PKMA)-based glasses modified with AlF(3) and BaF(2) are reported at room temperature. The observed energy levels of Nd(3+) ions in these glasses have been analysed through a semi-empirical free-ion Hamiltonian model. The spin-orbit interaction and net electrostatic interaction experienced by the Nd(3+) ions follow the trend as PKMA>PKMA+AlF(3)> PKMA+BaF(2) glasses. Judd-Ofelt analysis has been carried out on the absorption spectra of 1.0 mol% Nd(3+)-doped glasses to predict the radiative properties for the fluorescent levels of the Nd(3+) ion. Branching ratios and stimulated emission cross-sections show that the [Formula: see text] transition of the glasses under investigation has the potential for laser applications. The Inokuti-Hirayama model has been applied to investigate the non-radiative relaxation of the Nd(3+) ion emitting state, (4)F(3/2). Based on the decay curve analysis, concentration quenching of the (4)F(3/2) emission has been attributed to a cross-relaxation process between the Nd(3+) ions.

Population pharmacokinetic meta-analysis with efavirenz

A population-based pharmacokinetic (PK) model has been developed for efavirenz based on 16 phase I studies. The combined data set consisted of 334 healthy volunteers, 2,907 efavirenz dose administrations and 9,342 measured plasma concentrations across a range of doses from 100-600 mg. The pharmacokinetic structural model was a 2-compartment model with first-order absorption with differentiation between single- and multiple-dose exposure to account for known hepatic cytochrome P450 induction of efavirenz metabolism. Model-building was performed on the index data set (66% of the total database), as a data-splitting technique was used to validate the final model using NONMEM. The final model confirmed the appropriateness of separate clearance terms for single and multiple dose administration (2.65 versus 10.2 l/h, respectively). Clearance increased with dose and frequency of administration. A lower clearance was predicted in Asians and Blacks relative to Caucasians. A slightly lower clearance was observed in females relative to males (9.08 compared to 10.2 l/h in males) and interactions on clearance due to co-administration of fluconazole, ritonavir, rifampin, indinavir and azithromycin were identified. The magnitudes of these effects were small and did not suggest dose adjustment in the various subpopulations. With little exception, these results agree with the findings from the non-compartmental analyses. The residual variability was 21% CV and the intersubject variation in CL/F and V/F was 48 and 85%, respectively. The phase I meta-analysis was able to substantiate the pharmacokinetic characteristics of efavirenz derived from the composite of individual well-defined studies. The model was deemed adequate for subsequent evaluation in HIV-infected patients. Covariates and outlier classes identified in this phase I meta-analysis were similarly identified in subsequent analyses of patient data.

Nonfunctioning islet cell tumor presenting with ascites and portal hypertension

Nonfunctioning islet cell tumors commonly cause no symptoms. A 22-year-old woman presented with lump in the left hypochondrium, refractory high-protein ascites and evidence of left-sided portal hypertension. At exploratory laparotomy, a 30 cm x 15 cm mass was seen at the splenic hilum, with large collateral vessels around. Distal pancreatectomy with splenectomy was done. Histology of the mass showed malignant islet cell tumor infiltrating the spleen. The patient died in the postoperative period.

Clinico-pathological follow-up after total colectomy and straight ileo-anal anastomosis done for ulcerative colitis

BACKGROUND

Restorative proctocolectomy is used as surgical treatment for ulcerative colitis. We have earlier documented adaptative changes in the terminal ileum after total colectomy, and straight ileo-anal anastomosis.

AIM

To correlate the morphologic and functional changes in the ileal mucosa after total colectomy and hand-sewn straight ileo-anal anastomosis for ulcerative colitis.

METHODS

Thirty consecutive patients (age range 15-50 years, 24 men) who had undergone total colectomy, rectal mucosectomy and hand-sewn straight ileo-anal anastomosis for ulcerative colitis were included in the study. These patients were followed up at 3-monthly intervals following surgery for two years and later once every year for a median duration of 9.5 (range 1-17) years. The clinical parameters studied were weight gain, frequency of stools, nature of stools, nocturnal stool frequency and need for antidiarrheal drugs. At each follow-up visit they were subjected to per rectal ileoscopy with ileal biopsy and barium enema. Ileal biopsy was analyzed histologically and histochemically.

RESULTS

The clinical features improved over time, with average weight gain of 5 (range 1-7) Kg at one year. Frequency of stools decreased from 8-10 per day to 2-3 per day. The stools became semisolid and there was no need for antidiarrheal drug by the end of one year. All the patients showed adaptative changes in the ileum. The ileal mucosa was completely transformed into colonic type by the end of one year, colonoscopically (spacious lumen characteristic of colon), radiologically (disappearance of ileal characteristics with rectosigmoid-like appearance), histologically (blunting of villi with increase in goblet cells), and histochemically (sialomucin pattern to sulfomucin pattern).

CONCLUSIONS

The ileum undergoes adaptative changes with corresponding improvement of clinical parameters over time, after proctocolectomy and ileoanal anastomosis for ulcerative colitis.

Chiral analysis of drug substance in clinical plasma extracts using achiral HPLC with circular dichroism detection

A circular dichroism (CD) detector in series with a UV detector was used with reversed-phase gradient HPLC to do the chiral analysis of unresolved enantiomers of a single stereoisomer drug substance in extracts of clinical plasma samples. The CD/UV peak area ratio of the unresolved enantiomers in the plasma extracts was calculated and compared with pure drug substance standards to show that there was no racemization of the chiral center during pharmacokinetic studies. The CD detector can be used only with chiral compounds with a UV chromophore and the limit of detection was approximately 5 ng with the drug substance and chromatographic conditions used in this study.

Dihydrochalcones from Piper longicaudatum

Bioactivity-guided fractionation of an ethanolic extract of the leaves and twigs of Piper longicaudatum Trelease & Yunker (Piperaceae) resulted in the isolation of one new (1) and three known (2-4) dihydrochalcones. The known compounds are: 2',6'-dihydroxy-4'-methoxydihydrochalcone (2), 2',6',4-trihydroxy-4'-methoxydihydrochalcone (asebogenin) (3), and 2'-hydroxy-4'-methoxy-2'-[1-hydroxy-1-methylethyl]-2",3"-dihy- drofurano[4",5":5',6"]-3"-[2-hydroxy-5-methoxycarbonylphe- nyl]dihydrochalcone (piperaduncin B) (4). The new compound is 2'-hydroxy-4'-methoxy-2"-[2-hydroxy-5-methoxycarbonyl- phenyl]-furano[4",5":5',6']-dihydrochalcone (longicaudatin) (1). Compounds 1-4 were tested for antibacterial activity against S. aureus and methicillin-resistant S. aureus (MRSA); only compound 3 showed inhibitory activity (IC50 of 10 and 4.5 micrograms/ml, respectively).

Elimination pathways of [14C]losoxantrone in four cancer patients

Losoxantrone is an anthrapyrazole derivative in Phase III development in the U.S. for solid tumors, notably breast cancer. To obtain information on the routes of elimination of the drug, a study was conducted in four patients with advanced solid tumors, which involved intravenous administration of 100 microCi of [14C]losoxantrone for a total dose of 50 mg/m(2) during the first course of losoxantrone therapy. Blood, urine, and feces were collected for up to 2 weeks and were analyzed for total radioactivity and parent drug. In addition, feces were profiled for the presence of metabolites. Plasma concentrations of total radioactivity exhibited a temporal pattern similar to the parent drug. Combined recovery of administered total radioactivity from urine and feces was 70% with the majority (87%) of this radioactivity excreted in the feces, presumably via biliary excretion. Feces extracts were profiled for metabolites using a high-performance liquid chromatography method developed to separate synthetic standards of previously identified human urinary metabolites. Only intact losoxantrone was found in the feces. About 9% of the dose was excreted in the urine, primarily during the first 24 h and mostly in the form of parent compound. Collectively, these data indicate that fecal excretion of unmetabolized drug via biliary and/or intestinal excretion is the primary pathway of intravenously administered losoxantrone elimination in cancer patients with refractory solid tumors.

Antifungal chalcones from Maclura tinctoria

Five prenylated flavonoids, including one new natural product, were isolated from an ethanol extract of the leaves of Maclura tinctoria (L.) Gaud. The new compound has been characterized as 2',4',4,2''-tetrahydroxy-3'-[3''-methylbut-3''-enyl]chalcone (1). The known compounds were identified as 2',4',4-trihydroxy-3'-[3''-methylbut-3''-enyl]chalcone (isobavachalcone) (2), 4,2'-dihydroxy-2''-[1-hydroxy-1-methylethyl]-2'',3''-dihydrofurano[4'',5'':3',4']chalcone (bakuchalcone) (3), 4,4',5''-trihydroxy-6'',6''-dimethyldihydropyrano[2'',3'':5',6'']chalcone (bavachromanol) (4), and 5,7,3',4'-tetrahydroxy-6,8-diprenylisoflavone (6,8-diprenylorobol) (5). All the isolated compounds were evaluated against the AIDS-related opportunistic fungal pathogens, Candida albicans and Cryptococcus neoformans. Compound 2 was active against both yeasts.

Acquisition of Helicobacter pylori infection and reinfection after its eradication are uncommon in Indian adults

BACKGROUND

Eradication of Helicobacter pylori infection is known to decrease the recurrence rate of peptic ulcer disease. Data from India on the acquisition rate of H. pylori infection and reinfection after eradication are scant.

AIM

To study the rates of acquisition of H. pylori infection and of reinfection after eradication in Indian adult patients.

METHODS

We evaluated 116 consecutive patients with dyspepsia undergoing endoscopy. Sixty-four of them were H. pylori-positive on gastric antral biopsy (rapid urease test and histology). Patients diagnosed to have H. pylori infection were treated with a four-drug regimen (omeprazole, bismuth subcitrate, tetracycline, furazolidine) for 2 weeks; those failing H. pylori eradication were treated with a second regimen (lansoprazole, amoxycillin, secnidazole) for one week. Patients who were H. pylori-negative to begin with and those who had successful H. pylori eradication were followed up clinically and endoscopically every 3 months for a median of one year.

RESULTS

Ninety-six patients (50 H. pylori-positive) were available for study; the other 20 were lost to follow up after the first endoscopy. Fifty of the 96 (52%) were H. pylori-positive; four of these 50 patients did not follow up after first treatment. The eradication rate with the four-drug regimen was 89.1% (41/46). Four of the 5 non-responders eradicated H. pylori with the second regimen. At the end of median one year follow-up (range 9-15 months), one of the 45 patients (2.4%) who eradicated the organism developed reinfection; none of the 46 patients who were initially H. pylori-negative acquired new infection.

CONCLUSIONS

The risk of reinfection after eradication is low in Indian subjects at the end of one year. The rate of acquisition of new infection is also low in the adult population.

Hepatic sickling crisis mimicking recurrent cholangitis

A 22-year-old man with homozygous sickle cell disease presented with recurrent fever, right upper quadrant pain and jaundice. Liver biopsy confirmed the diagnosis of hepatic sickling crisis; the symptoms responded to hydroxyurea therapy. Hepatic vasocclusive crisis can diagnosed on liver biopsy, and need not be a diagnosis of exclusion.

Phase I safety and pharmacokinetic studies of brequinar sodium after single ascending oral doses in stable renal, hepatic, and cardiac allograft recipients

Brequinar sodium (BQR), a substituted 4-quinoline carboxylic acid, was in clinical development in combination with cyclosporine (CsA) as a potentially effective therapy for the treatment and prophylaxis of rejection in organ transplant patients. This phase I study was performed in stable renal, hepatic, and cardiac transplant patients receiving CsA and prednisone maintenance therapy for immunosuppression. The pharmacokinetic objectives of this study were to characterize the pharmacokinetics of (a) single oral 0.5- to 4-mg/kg doses of BQR when given in combination with CsA and prednisone to stable renal, hepatic, and cardiac transplant patients and (b) steady-state oral doses of CsA, with and without single oral doses of BQR. In all three patient populations, the pharmacokinetics of BQR were characterized by a lower oral clearance (12-19 mL/min) than that seen in previous studies in patients with cancer (approximately 30 mL/min at similar doses) and a long terminal half life (13-18 hrs). This slower oral clearance for BQR could be due either to a drug interaction between BQR and CsA or to altered clearance or metabolic processes in patients with transplants. Steady-state CsA trough levels and the oral clearance of CsA were not affected by BQR coadministration. Among the three transplant populations, the cardiac transplant patients had lower oral clearance values of BQR and of CsA. The cause of this lower clearance is not known. Safety results indicate that BQR was well tolerated by this patient population.

Mesenteric vasculopathy in intestinal tuberculosis

BACKGROUND

Involvement of mesenteric vessels in intestinal tuberculosis and its role in the pathogenesis of the intestinal changes have not been studied histologically.

AIM

To study mesenteric vessels in patients undergoing surgery for complications of intestinal tuberculosis.

METHODS

Resected intestinal specimens from 68 patients presenting with intestinal perforation and intestinal obstruction were examined; involvement of the major mesenteric vessels was evaluated.

RESULTS

Granulomas were seen in the vessel wall in one case and near the vessel wall in 11 cases, intraluminal thrombi were seen in 23 cases, and subintimal fibrosis in nine cases. Perivascular cuffing was seen in intramural and subserosal vessels in ten cases.

CONCLUSIONS

Changes in the vessel wall may lead to gut ischemia, which may contribute to the development of strictures and stercoral perforation in intestinal tuberculosis.

Effect of drying conditions on the taxane content of the needles of ornamental Taxus

The effect of drying intact clippings of Taxus on the recovery of taxol and related compounds was studied under different drying conditions which included tobacco drying barn, greenhouse, shadehouse, air conditioned laboratory, oven, and freeze-drying. For clippings dried under tobacco barn, greenhouse, oven, and freeze-drying conditions, nearly total recovery of the expected levels based upon projections from analysis of fresh biomass was observed for taxol and cephalomannine. However, only 75-80% of the expected values for 10-deacetyltaxol and 10-deacetylbaccatin III were found. When the length of drying was extended up to 10 and 15 days as in the shadehouse and laboratory conditions, the recovery of all taxanes was adversely affected.

Bleeding ileal schwannoma

We report a case of ileal schwannoma who presented with bleeding per rectum. Three-vessel angiogram was the only diagnostic investigation, and revealed tumor blush in the mid-ileal region. On exploration, an intraluminal mass was found in the mid-ileal region along with a feeding vessel in the mesentery. Resection of the involved ileum with end-to-end anastomosis was done. Histopathology showed benign schwannoma of ileum involving the submucosa, muscularis propria and serosa.

Variability in the pharmacokinetics and pharmacodynamics of low dose aspirin in healthy male volunteers

Data describing the pharmacokinetics and pharmacodynamics of low dose aspirin (acetylsalicylic acid; ASA) are limited. This single-center study was designed to determine the rate and extent of oral absorption of 80-mg ASA tablets in healthy, young male subjects and to assess the intra- and inter-subject variability of ASA pharmacokinetics and platelet aggregation effects. Ten subjects each received a single, open-label, oral 80-mg ASA dose on three separate days. Each dose was separated by a 2-week washout interval. Blood samples for pharmacokinetic determinations of ASA and its metabolite, salicylic acid (SA) and platelet aggregation studies were obtained at scheduled timepoints before and up to 24 hours after each dose. Peak plasma ASA levels of 1 microgram/mL were achieved within 30 minutes. Peak plasma SA levels of approximately 4 micrograms/mL were attained in 1 hour. The terminal half-lives (t1/2) of ASA and SA were 0.4 and 2.1 hours, respectively. Both ASA and SA pharmacokinetics and the platelet aggregation response to ASA exhibited considerable intra- and inter-subject variability. Inhibition of platelet aggregation was found to relate with ASA area under the plasma concentration versus time curve (AUC).

Adult Hirschsprung's disease

Hirschsprung's disease in adulthood is a rare entity. We report Hirschsprung's disease in a 35-year-old woman who had absence of anorectal inhibitory reflex on manometric studies.

Non-specific granulomatous inflammatory lesions of small bowel

The entity of nonspecific granulomatous inflammatory lesions(NSGIL) of the small bowel is a diagnostic and therapeutic dilemma. Data of 52 histopathologically proven cases of NSGIL seen by us between 1986 and 1991 were analysed. All these patients presented with either intestinal obstruction or perforation. They were thoroughly evaluated and investigated for tuberculosis. Of the 52 patients, 6 patients received antitubercular therapy (ATT) before and after surgery and 32 patients only after surgery. Fourteen patients did not receive ATT. Surgical procedures undertaken included stricturoplasty, resection/anastomosis and simple suturing of perforation. No complications were seen in patients who received ATT; however, six of 14 patients who did not receive ATT developed wound sepsis and 2 developed partial wound dehiscence. Many of these NSGIL lesions could be tuberculous in etiology though typical caseating granulomas were not seen.

Simultaneous quantification of an anti-inflammatory compound (DuP 697) and a potential metabolite (X6882) in human plasma and urine by high-performance liquid chromatography

A high-performance liquid chromatographic (HPLC) method using fluorescence detection has been developed for the simultaneous analysis of low nanogram concentrations of an anti-inflammatory drug, 5-Bromo-2-(4-fluorophenyl)-3-[4-(methylsulfonyl)phenyl]thiophene (DuP 697), and a potential metabolite (X6882) in human plasma and of DuP 697 in human urine. This assay method used an EM Separations Lichrospher C18 endcapped column. The mobile phase was acetonitrile-water (75:25, v/v). The detection of DuP 697 and X6882 was by fluorescence at excitation and emission wavelengths of 256 and 419 nm, respectively. The chromatographic system could separate DuP 697 from X6882, the external standard (anthracene), and other endogenous substances present in human plasma. In human plasma the limits of quantification for DuP 697 and X6882 were 3 and 20 ng/ml, respectively; the limit of quantification for DuP 697 in human urine was 5 ng/ml. These compounds were shown to be stable in frozen (-20 degrees C) human plasma and urine for at least 9 weeks. The assay described has been used to characterize DuP 697 pharmacokinetics after oral administration in humans.

Fibrolamellar hepatocellular carcinoma

Fibrolamellar hepatocellular carcinoma, a histological variant of hepatocellular carcinoma, distinct pathological and clinical features and a better prognosis than other types of hepatocellular carcinoma. We report here a patient who was treated on successful surgically.

Congestive jejunopathy in portal hypertension

Twenty six patients with portal hypertension of different aetiologies were studied for endoscopic evidence of congestive gastroduodenopathy and histological evidence of congestive gastropathy and jejunopathy. Per oral biopsies of jejunum were taken by Watson's capsule. Normal biopsy tissues obtained from the antrum (26), fundus (10), and jejunum (26) were used as controls. Endoscopy showed congestive changes in the fundus (17 cases), antrum (17), and duodenum (4). Duodenopathy correlated with changes in the antrum but not in the fundus. Histology showed an increase in the size and number of vessels in the jejunal villi ('congestive jejunopathy') in 22 patients. These correlated with histological evidence of gastropathy in the fundus but not in the antrum. The incidence of congestive jejunopathy did not correlate with the Child-Pugh score in patients with cirrhosis or with the number of sclerotherapy sessions received. Congestive jejunopathy is part of the spectrum of congestive gastroenteropathy and occurs at least as frequently as changes in the stomach and duodenum. The clinical import of these jejunal changes remains to be explained.