Ultrasound guided percutaneous fine needle aspiration cytology of pancreas: a review of 61 cases

The study includes 61 cases which were subjected to ultrasound (US) guided fine needle aspiration cytology (FNAC) to find out the utility of this technique in the diagnosis of pancreatic lesions. Age of the patients ranged from 23 to 85 years with a median of 50 years. Male to female ratio was 36:25. One or more clinical diagnoses were offered in 16 and in 9 of these, the disease was related to pancreas. Subsequent to US, the lesions were localized to pancreas in 57 and the nature of pathology in the pancreatic lesion could be diagnosed in 31. By FNAC, 31 cases (50.8%) were diagnosed to have pancreatic malignancy which included adenocarcinoma (23 cases), papillary cystic tumour (1), muco-epidermoid carcinoma (1), acinic cell carcinoma (1), islet cell tumor (1), and non Hodgkin lymphoma (4). FNAC of liver in 2 cases and retroperitoneal lymph node in a case of pancreatic adenocarcinoma revealed metastasis. During follow up, 1 case of non Hodgkin's lymphoma showed CSF involvement. Three cases (4.9%) were suspected to have epithelial malignancy of which one was confirmed as an adenocarcinoma following surgery and histology. Four (6.6%) were benign lesions which included nonspecific inflammation (2 cases), tuberculous pancreatitis (1) and pseudopancreatic cyst (1). The remaining 23 cases (37.7%) had normal or inadequate cytology. Of these, FNAC of liver showed metastasis in 2 cases and one case each were diagnosed as adenocarcinoma and pseudopancreatic cyst respectively following surgery. None of the patients had any complication following FNAC. We recommend US guided FNAC to be routinely used for diagnosis of pancreatic lesion.     

Synthesis and characterization of porphyrin electrochromic and photovoltaic electropolymers

New asymmetric porphyrins, with electroactive functionalities were synthesized. 5,15-Bis[4(-N,N-diphenylamino)phenyl]-10,20-bis[3-(N-ethylcarbazoyl)]porphyrin and its Zn(II) derivative allow the electrochemical formation of conjugated, conducting and stable polymeric films over semitransparent indium-tin oxide surface. The spectral changes observed upon oxidation of the films produced different colorations. The polymeric materials showed the generation of photoinduced charge separation states and charge migration upon porphyrin excitation, making them promising candidates for application in optoelectronics devices.     

Structured phosphatidylcholine with elevated content of conjugated linoleic acid: Optimization by response surface methodology

Structured phosphatidylcholine was successfully produced by immobilized phospholipase A₁ catalyzed acidolysis of phosphatidylcholine and CLA. Response surface methodology was applied to optimize the reaction system using three process parameters: enzyme load, temperature, and substrates molar ratio. Optimal conditions obtained from the model were 15% enzyme load at 55°C for a 1:4 (PC/CLA) substrates molar ratio, which produced a yield of 85.8% of CLA incorporation. The total correlation coefficient (R²) was 0.92 and no lack of fit was detected. This suggests the fitness of the model obtained and it suggests that the model is sufficiently accurate to estimate the incorporation of CLA into PC. Practical applications: This study could contribute to process development for enzyme catalyzed phospholipid modification. By changing the fatty acid composition of lecithin, delivery of desired (beneficial) fatty acids could be better achieved. Additionally, emulsification properties of the phospholipids could open a wide area of applications in the food and cosmetic industries.     

Optimized interesterification of virgin olive oil with a fully hydrogenated fat in a batch reactor: Effect of mass transfer limitations

The lipase‐catalyzed interesterification of virgin olive oil and fully hydrogenated palm oil (FHPO) was studied in a batch reactor operating at 75 °C. The reactions between olive oil {rich in OOO (32.36%), OPO (21.7%) and OLO (11.6%) [L = linoleic; O = oleic; P = palmitic acid]} and the fully hydrogenated fat {(36.5% PSP, 28.8% PPP, 23.2% SPS) [S = stearic acid]} produced semi‐solid fats. For an initial weight ratio of olive oil to FHPO of 60 : 40, the reaction product is a complex mixture of triacylglycerol (TAG) species. The TAG profile of the fat product is time dependent. Because of the high viscosity of the liquid reagent phase, it was important to determine if mass transfer effects were significant. Hence, the reaction was optimized with respect to the type and speed of agitation employed, temperature, use of solvent, and the type of biocatalyst. Three immobilized lipases [from Thermomyces lanuginosus (TL IM), Rhizomucor miehei (RM IM) and Candida antarctica B (Novozym 435)] were compared as catalysts for the interesterification reaction. Equilibrium is reached four times faster (in 1–4 h) with a magnetic stirrer to provide agitation than when agitation is not sufficient, i.e. when orbital agitation is employed. Equilibrium was reached faster with Lipozyme TL IM than with the other two lipases. The effects of all the factors investigated on the composition of the products have also been determined. Semi‐solid fats obtained with the non‐specific Novozym 435 contain levels of unsaturated fatty acid residues on sn‐2 sites that are similar to the products obtained with the 1(3)‐regiospecific enzymes Lipozyme TL IM and RM IM. The chemical properties of the product semi‐solid fat were characterized. The fat prepared using optimal reaction conditions contained 17.20% OPO, 13.61% OOO, 11.09% POP, and 10.35% OSP isomers as the primary products. The induction time obtained in the assay of the oxidative stability of the fat product was 21 h at 98 °C. The lipases Lipozyme TL IM and Novozym 435 were very stable with residual activities of 90 and 100%, respectively, after 15 batch reaction cycles.     

Kinetic constants of alpha-methyl-D-glucoside transport in the chick small intestine during perinatal development

BACKGROUND: Experimental evidence suggests that neutralizing antibodies could constitute an important factor in the control of AIDS progression and that the V3 loop of gp120 constitutes the main target for such purposes. We have previously developed two neutralizing murine monoclonal antibodies (Mabs) against the V3 region of the HIV-1 MN strain. OBJECTIVES: To characterize those Mabs in terms of fine specificity and DNA sequence of their V regions and to study if Fab fragments retain their neutralizing potential in vitro. STUDY DESIGN: A set of 12-mer alanine substituted peptides were employed for epitope mapping using two ELISA procedures: (1) indirect, with each peptide bound to polystyrene plates, and (2) competitive, with co-incubation of peptides and Mabs in solution. The V regions of both Mabs were PCR amplified from cDNA and their nucleotide sequences were determined. Finally, Fab fragments of Mab 10F10 were generated and their neutralizing capacity against the MN isolated was assessed. RESULTS: We first restricted the minimal length of the epitopes recognized by 2C4 and 10F10 to the 12-mer peptide KRIHIGPGRAFY. The core of the epitopes recognized by Mabs 2C4 and 10F10 were IHIGP-R and IHIG-R, respectively. While substitution of proline in position 7 completely abolished the binding of 2C4, it only reduced that of 10F10 by 50%. Finally, Fab fragments of Mab 10F10 were still able to neutralize the HIV-1 MN strain in vitro. CONCLUSION: This subtle distinction in the fine mapping of the epitope recognized by Mabs 2C4 and 10F10 should correspond to three amino acid differences that we found in the heavy chain V-regions. The Fab fragments of Mab 10F10 retained the neutralizing capacity. This indicates that HIV neutralization by anti V3 Mabs is an Fc independent process.     

Risk analysis of linear accelerator radiosurgery

PURPOSE: To evaluate the toxicity of stereotactic single-dose irradiation and to compare the own results with already existing risk prediction models. METHODS AND MATERIALS: Computed tomography (CT) or magnetic-resonance (MR) images, and clinical data of 133 consecutive patients treated with linear accelerator radiosurgery were analyzed retrospectively. Using the Cox proportional hazards model the relevance of treatment parameters and dose-volume relationships on the occurrence of radiation-induced tissue changes (edema, localized blood-brain barrier breakdown) were assessed. RESULTS: Sixty-two intraparenchymal lesions (arteriovenous malformation (AVM): 56 patients, meningioma: 6 patients) and 73 skull base tumors were selected for analysis. The median follow-up was 28.1 months (range: 9.0-58.9 months). Radiation-induced tissue changes (32 out of 135, 23.7%) were documented on CT or MR images 3.6-58.7 months after radiosurgery (median time: 17.8 months). The actuarial risk at 2 years for the development of neuroradiological changes was 25.8% for all evaluated patients, 38.4% for intraparenchymal lesions, and 14.6% for skull base tumors. The coefficient: total volume recieving a minimum dose of 10 Gy (VTREAT10) reached statistical significance in a Cox proportional hazards model calculated for all patients, intraparenchymal lesions, and AVMs. In skull base tumors, the volume of normal brain tissue covered by the 10 Gy isodose line (VBRAIN10) was the only significant variable. CONCLUSIONS: These results demonstrate the particular vulnerability of normal brain tissue to single dose irradiation. Optimal conformation of the therapeutic isodose line to the 3D configuration of the target volume may help to reduce side effects.     

Neutralizing antibodies to Escherichia coli Vero cytotoxin 1 and antibodies to O157 lipopolysaccharide in healthy farm family members and urban residents

An enzyme-linked immunosorbent assay (ELISA) to detect antibodies to Escherichia coli O157 lipopolysaccharide (LPS) was developed with sera from 63 children with confirmed recent E. coli O157 infection and from 256 age-stratified urban controls. The median ELISA values for control and case sera were 0.05 (interquartile range, 0 to 0.20; mean +/- standard deviation [SD], 0.15 +/- 0.22) and 1.41 (interquartile range, 1.11 to 1.59; mean +/- SD, 1.41 +/- 0.53), respectively (P < 0.001). With a breakpoint of 0.59 (mean ELISA value of the control sera + 2 SDs), the assay had a sensitivity, specificity, and positive and negative predictive values of 95, 94, 80, and 98%, respectively, for recent E. coli O157 infection. The O157 LPS assay and Vero cytotoxin (VT) 1-neutralizing-antibody (NAb) assay were used to compare the relative frequencies of O157 LPS antibodies and VT1-NAbs in an age-stratified urban population from Toronto, Ontario, Canada, and in 216 healthy family members from dairy farm in southern Ontario. The frequency of O157 LPS antibodies was about threefold higher in dairy farm residents (12.5%) than in urban residents (4.7%) (P < 0.01). Similarly, the frequency of VT1-NAbs was about sixfold higher in dairy farm residents (42.0%) than in urban residents (7.7%) (P < 0.001). These findings are consistent with a greater level of exposure of dairy farm residents to VT-producing E. coli (VTEC) strains. The high rate of seropositivity to VT1 in farm residents probably reflects the booster effect of repeated VTEC exposures and argues against a sustained generalized immunosuppressive effect of VT1. Seroepidemiological studies may help in assessing the level of exposure of different populations to VTEC strains.     

Functional anatomy of pointing and grasping in humans

The functional anatomy of reaching and grasping simple objects was determined in nine healthy subjects with positron emission tomography imaging of regional cerebral blood flow (rCBF). In a prehension (grasping) task, subjects reached and grasped illuminated cylindrical objects with their right hand. In a pointing task, subjects reached and pointed over the same targets. In a control condition subjects looked at the targets. Both movement tasks increased activity in a distributed set of cortical and subcortical sites: contralateral motor, premotor, ventral supplementary motor area (SMA), cingulate, superior parietal, and dorsal occipital cortex. Cortical areas including cuneate and dorsal occipital cortex were more extensively activated than ventral occipital or temporal pathways. The left parietal operculum (putative SII) was recruited during grasping but not pointing. Blood flow changes were individually localized with respect to local cortical anatomy using sulcal landmarks. Consistent anatomic landmarks from MRI scans could be identified to locate sensorimotor, ventral SMA, and SII blood flow increases. The time required to complete individual movements and the amount of movement made during imaging correlated positively with the magnitude of rCBF increases during grasping in the contralateral inferior sensorimotor, cingulate, and ipsilateral inferior temporal cortex, and bilateral anterior cerebellum. This functional-anatomic study defines a cortical system for "pragmatic' manipulation of simple neutral objects.     

An Epstein-Barr virus-associated superantigen

More than 90% of adults are latently infected with Epstein-Barr virus (EBV), the causative agent of infectious mononucleosis, a self-limiting lymphoproliferative disease characterized by extensive T cell activation. Reactivation of this herpesvirus during immunosuppression is often associated with oncogenesis. These considerations led us to analyze the early events that occur after exposure of the immune system to EBV. Strong major histocompatibility complex (MHC) class II-dependent but not MHC-restricted, T cell proliferation was observed in vitro in response to autologous, lytically infected EBV-transformed B cells. By measuring the appearance of the early activation marker CD69 on individual T cell V beta subsets, we could demonstrate selective activation of human V beta 13- T cells. This was confirmed with murine T cell hybridomas expressing various human BV genes. While EBV- Burkitt's lymphoma cells were nonstimulatory, they induced V beta-restricted T cell activation after EBV infection. EBV specific activation was also demonstrated in cord blood cells, excluding a recall-antigen response. Thus, all of the characteristics of a superantigen-stimulated response are seen, indicating that induction of the EBV lytic cycle is associated with the expression of a superantigen in B cells. A model is presented proposing a role for the superantigen in infection, latency, and oncogenesis.     

The Australian Vietnam Veterans Health Study: II. self-reported health of veterans compared with the Australian population

BACKGROUND: Self-reported physical health status of Australian Vietnam veterans was determined 20-25 years after the war and its relation to combat was investigated. METHOD: An epidemiological cohort study of a simple random sample of Army veterans posted to Vietnam between 1964 and 1972 was conducted with personal interviews using the Australian Bureau of Statistics Health Interview Survey questionnaire to compare veterans with the Australian population and a 21-item combat exposure index used to measure the relationship of combat to physical health. RESULTS: Veterans reported greater health service usage and more recent health actions than population expectations. They also reported excess health problems in almost all recent illness disease categories except endocrine conditions and cardiovascular conditions; only 6 of 37 chronic disease groups were not elevated compared to the population. Adjustment for non-response changed estimates only slightly. Combat exposure was significantly related to reports of recent and chronic mental disorders, recent hernia and chronic ulcer, recent eczema and chronic rash, deafness, chronic infective and parasitic disease, chronic back disorders and symptoms, signs and ill-defined conditions. CONCLUSION: Combat exposure may have significantly increased reports of only some health problems. A general position to complain as a result of psychological conditions due to combat is not consistent with the lack of relationship between combat and reports of physical conditions.