Accumulation of humic acid in DET/DGT gels

Gel layer based sensors are increasingly employed for dynamic trace metal speciation analysis in aquatic and soil media. In DGT (Diffusive Gradient in Thin film), polyacrylamide hydrogels are commonly used for the diffusive gel layer. While some effects of humic and fulvic acids on the DGT detection of metal species have been observed, the gel permeation properties of the actual humic and fulvic acid compounds themselves have not been analyzed thus far. Here we show with DET (Diffusive Equilibrium in Thin film) that these natural complexing agents do enter the gel layer, and that humic acids even appear to accumulate in the gel, with enrichment factors typically on the order of 10. The results have consequences for the interpretation of DGT-data on metal fluxes from aquatic media containing humics and fulvics.

Clinical obligations and public health programmes: healthcare provider reasoning about managing the incidental results of newborn screening

BACKGROUND

Expanded newborn screening generates incidental results, notably carrier results. Yet newborn screening programmes typically restrict parental choice regarding receipt of this non-health serving genetic information. Healthcare providers play a key role in educating families or caring for screened infants and have strong beliefs about the management of incidental results.

METHODS

To inform policy on disclosure of infant sickle cell disorder (SCD) carrier results, a mixed-methods study of healthcare providers was conducted in Ontario, Canada, to understand attitudes regarding result management using a cross-sectional survey (N = 1615) and semistructured interviews (N = 42).

RESULTS

Agreement to reasons favouring disclosure of SCD carrier results was high (65.1%-92.7%) and to reasons opposing disclosure was low (4.1%-18.1%). Genetics professionals expressed less support for arguments favouring disclosure (35.3%-78.8%), and more agreement with arguments opposing disclosure (15.7%-51.9%). A slim majority of genetics professionals (51.9%) agreed that a reason to avoid disclosure was the importance of allowing the child to decide to receive results. Qualitatively, there was a perceived "duty" to disclose, that if the clinician possessed the information, the clinician could not withhold it.

DISCUSSION

While a majority of respondents perceived a duty to disclose the incidental results of newborn screening, the policy implications of these attitudes are not obvious. In particular, policy must balance descriptive ethics (ie, what providers believe) and normative ethics (ie, what duty-based principles oblige), address dissenting opinion and consider the relevance of moral principles grounded in clinical obligations for public health initiatives.

The lived experience of hope among parents of a child with Duchenne muscular dystrophy: perceiving the human being beyond the illness

OBJECTIVES

Duchenne muscular dystrophy (DMD) is genetically determined, progressive and incurable. Our study's primary objective was to describe the lived experience of hope among parents of a child with DMD.

METHODS

Semi-structured interviews were conducted with 12 parents having a child with DMD. A qualitative/ phenomenological approach was utilized to analyse the essential aspects of this experience.

RESULTS

We show that the experience of parental hope emerges from the cognitive appraisal of DMD. The child's illness can be perceived in three ways: as a severe loss, a call to adapt or a way to rediscover the child. Each of these appraisals leads to different ways of hoping. Parents can hope for a cure, the child's well-being or to see their child becoming a whole person. Hope can help parents absorb the initial crisis, sustain their adaptation or prepare for the fatal outcome.

DISCUSSION

Previous research has demonstrated that cognitive appraisal plays a central role in psychosocial adaptation to illness. Our research indicates that perception can also shape the nature of hope and suggests that health professionals should pay particular attention to the nature of parental hope. The fabric of parental hope can give an indication of how parents are coping and adjusting.

Potent bactericidal action of a flavonoid fraction isolated from the stem bark of Butea frondosa

The flavonoid fraction isolated from the ethyl acetate fraction (BF-1) of Butea frondosa (L.) stem bark exhibited distinct antimicrobial activity when tested against 129 bacterial strains belonging to 9 different genera of both gram-positive and gram-negative types. Minimum inhibitory concentration (MIC) of the fraction BF-1 was determined following NCCLS guidelines using the agar dilution method. Twenty-four out of 36 strains of Staphylococcus aureus were inhibited by 50-200 mg/l of the fraction. This fraction also inhibited strains of Bacillus spp., Shigella spp., Salmonella spp. and even a few Pseudomonas at concentrations between 50-200 mg/l. Other bacteria including Escherichia coli, Vibrio cholerae and V. parahaemolyticus were moderately sensitive to BF-1. In the in vivo studies, this fraction offered significant protection to Swiss albino mice at a concentration of 80 microg/mouse (p<0.001) when they were challenged with 50 median lethal dose of Salmonella enteritidis NCTC 74. A fraction named BF-1 that was isolated from an ethyl acetate fraction of Butea frondosa provided protection against an infection from a Salmonella enteritidis NCTC strain.

Ethical, legal, and social issues in health technology assessment for prenatal/preconceptional and newborn screening: a workshop report

Prenatal/preconceptional and newborn screening programs have been a focus of recent policy debates that have included attention to ethical, legal, and social issues (ELSIs). In parallel, there has been an ongoing discussion about whether and how ELSIs may be addressed in health technology assessment (HTA). We conducted a knowledge synthesis study to explore both guidance and current practice regarding the consideration of ELSIs in HTA for prenatal/preconceptional and newborn screening. As the concluding activity for this project, we held a Canadian workshop to discuss the issues with a diverse group of stakeholders. Based on key workshop themes integrated with our study results, we suggest that population-based genetic screening programs may present particular types of ELSIs and that a public health ethics perspective is potentially highly relevant when considering them. We also suggest that approaches to addressing ELSIs in HTA for prenatal/preconceptional and newborn screening may need to be flexible enough to respond to diversity in HTA organizations, cultural values, stakeholder communities, and contextual factors. Finally, we highlight a need for transparency in the way that HTA producers move from evidence to conclusions and the ways in which screening policy decisions are made.

Development of a clinical assay for detection of GAA mutations and characterization of the GAA mutation spectrum in a Canadian cohort of individuals with glycogen storage disease, type II

Glycogen storage disease, type II (GSDII; Pompe disease; acid maltase deficiency) is an autosomal recessive disease caused by mutations of the GAA gene that lead to deficient acid alpha-glucosidase enzyme activity and accumulation of lysosomal glycogen. Although measurement of acid alpha-glucosidase enzyme activity in fibroblasts remains the gold standard for the diagnosis of GSDII, analysis of the GAA gene allows confirmation of clinical or biochemical diagnoses and permits predictive and prenatal testing of individuals at risk of developing GSDII. We have developed a clinical molecular test for the detection of GAA mutations based on cycle sequencing of the complete coding region. GAA exons 2-20 are amplified in six independent PCR using intronic primers. The resulting products were purified and sequenced. Preliminary studies using this protocol were conducted with DNA from 21 GSDII-affected individuals from five centers across Canada. In total, 41 of 42 mutations were detected (96.7% detection rate). Mutations spanned intron 1 through exon 19 and included nine novel mutations. Haplotype analysis of recurrent mutations further suggested that three of these mutations are likely to have occurred independently at least twice. Additionally, we report the identification of the c.-32-13T>G GAA mutation in an individual with infantile variant GSDII, despite reports of this mutation being associated almost exclusively with late-onset forms of the disease. The development of a clinical molecular test provides an important tool for the management and counseling of families and individuals with GSDII, and has provided useful information about the GAA mutation spectrum in Canada.

Device-associated nosocomial infection rates in intensive care units of seven Indian cities. Findings of the International Nosocomial Infection Control Consortium (INICC)

We sought to determine the rate of healthcare-associated infection (HCAI), microbiological profile, bacterial resistance, length of stay (LOS) and excess mortality in 12 ICUs of the seven hospital members of the International Infection Control Consortium (INICC) of seven Indian cities. Prospective surveillance was introduced from July 2004 to March 2007; 10 835 patients hospitalized for 52 518 days acquired 476 HCAIs, an overall rate of 4.4%, and 9.06 HCAIs per 1000 ICU-days. The central venous catheter-related bloodstream infection (CVC-BSI) rate was 7.92 per 1000 catheter-days;the ventilator-associated pneumonia (VAP) rate was 10.46 per 1000 ventilator-days; and the catheter-associated urinary tract infection (CAUTI) rate was 1.41 per 1000 catheter-days. Overall 87.5% of all Staphylococcus aureus HCAIs were caused by meticillin-resistant strains, 71.4% of Enterobacteriaceae were resistant to ceftriaxone and 26.1% to piperacillin-tazobactam; 28.6% of the Pseudomonas aeruginosa strains were resistant to ciprofloxacin, 64.9% to ceftazidime and 42.0% to imipenem. LOS of patients was 4.4 days for those without HCAI, 9.4 days for those with CVC-BSI, 15.3 days for those with VAP and 12.4 days for those with CAUTI. Excess mortality was 19.0% [relative risk (RR) 3.87; P < or = 0.001] for VAP, 4.0% (RR 1.60; P=0.0174) for CVC-BSI, and 11.6% (RR 2.74; P=0.0102) for CAUTI. Data may not accurately reflect the clinical setting of the country and variations regarding surveillance may have affected HCAI rates. HCAI rates, LOS, mortality and bacterial resistance were high. Infection control programmes including surveillance and antibiotic policies are a priority in India.

Breakthrough adsorption study of migratory nickel in fine-grained soil

The present study was conducted to evaluate the breakthrough curve for nickel adsorption in fine-grained soil from a nearby ash pond site of a thermal power plant. Nickel was found to be the major polluting solute in the ash sluicing wastewater. The adsorption of nickel by vertical soil column batch test and horizontal migration test was carried out in the laboratory. Field investigation was conducted also, by installing test wells around the ash pond site. Experimental results showed a good adsorptive capacity of soil for nickel ions. The breakthrough curves showed a reasonable fitting with a one-dimensional mathematical model. The breakthrough curves yielded from field test results showed good agreement with a two-dimensional mathematical model.

Thermodynamics of the Interaction of Globular Proteins with Powdered Stearic Acid in Acid pH

Adsorption isotherms of different globular proteins and gelatin on strearic acid particles have been studied as a function of biopolymer concentration, ionic strength of the medium, and temperature. The effect of neutral salts including CaCl2, Na3PO4, and urea on the adsorption isotherms has been also investigated. It is observed that the extent of adsorption (Gamma2(1)) increases in two steps with the increase of biopolymer concentration (C2) in the bulk. Gamma2(1) increases with an increase of C2 until a steady maximum value Gamma2(m) is reached at a critical concentration C2(m). After initial saturation, Gamma2(1) again increases from Gamma2(m) without reaching any limiting value due to the surface aggregation of the protein. The values of the standard free energy change for adsorption have been calculated on the basis of the Gibbs equation. The standard entropy and enthalpy changes are also calculated.

Phoenix sylvestris Roxb pollen allergy: a 2-year randomized controlled trial and follow-up study of immunotherapy in patients with seasonal allergy in an agricultural area of West Bengal, India

BACKGROUND

Although the efficacy of allergen immunotherapy has been demonstrated in seasonal pollen allergy, there is no report of a double-blind placebo-controlled trial with standardized pollen extract in seasonal respiratory allergy from India. In the agricultural area of eastern India, Phoenix sylvestris Roxb or date sugar palm is grown or cultivated and seasonal allergic rhinitis is common during the pollen season.

OBJECTIVE

The objective of the present study was to observe the clinical and immunological changes during a 2-year double-blind placebo-controlled trial of immunotherapy with standardized P sylvestris pollen extract in respiratory patients sensitive to pollen from this wild date palm. Thirty-five subjects with typical seasonal allergic rhinitis with or without bronchial asthma were selected. A symptom-medication score (based on a questionnaire and diary) was correlated with pollen counts as recorded in a Burkard sampler. Eighteen subjects were randomized to a specific immunotherapy (SIT) group receiving regular injections containing standardized allergen extract and 17 to a placebo control group. Changes in the level of specific immunoglobulin (Ig) E, IgG1, and IgG4 were recorded at 3-month intervals. Measurement of wheal diameter, total IgE level and forced expiratory volume in 1 second (FEV1) were performed before starting and a month after finishing therapy.

RESULTS

The SIT group showed decreases of 33.5% and 57% from the baseline symptom-medication scores during the first and second treatment season, respectively. This group showed significant decreases in skin-reactivity to P sylvestris pollen extract and in specific IgE levels, and significant increases in FEV,, specific IgGI (1.95-3.2 times higher) and IgG4 (21.24-30.83 times higher). There were no significant changes in total IgE levels. The control group showed no significant changes for any parameter except the development of new sensitization in 2 cases (to Saccharum officinarum pollen grain and Alternaria species spores). The rate of local adverse reactions was 0.024%.

CONCLUSION

After a 2-year study, allergen immunotherapy with standardized P sylvestris pollen extract was found to be effective in seasonal respiratory allergic subjects susceptible to P sylvestris pollen with a narrow range of sensitization.

Aerobiological and immunochemical studies on Carica papaya L. pollen: an aeroallergen from India

BACKGROUND

Carica papaya L. is a fruit yielding tree, wildly grown or cultivated in the tropics and subtropics. Its pollen grain has been reported to be airborne and cause immunoglobulin E (IgE)-mediated hypersensitivity.

OBJECTIVE

To conduct long-term aerobiological study on Carica pollen, along with aeroallergenic particles originating from it and to identify vis-a-vis characterize an important IgE-reactive component present in this pollen.

METHODS

The seasonal and diurnal periodicities of airborne C. papaya pollen were recorded in a 5-year survey using a Burkard volumetric sampler. The allergenic potential was studied by skin prick tests, IgE-enzyme-linked immunosorbent assay (ELISA) and also by aeroallergen immunoblotting. The total pollen extract was fractionated by Sephacryl S-200 column, and out of the eluted five fractions, the maximum IgE-reactive fraction (as found in ELISA inhibition) was resolved into five major subfractions in reverse-phase high-performance liquid chromatography (RP-HPLC). The subfraction with optimum IgE reactivity was studied by activity gel, native and nonreducing sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE). The homogeneity of the isolated protein fraction was checked by crossed immunoelectrophoresis with rabbit antisera and IgE reactivity was confirmed by ELISA inhibition and immunoblotting using individual patient sera.

RESULTS

The Carica pollen occurred in the air round the year with peaks during January and September-October. Among a patient population of 1000, skin-test results showed 27.8% +1 level and 5.6% +2/+3 level reactions. In aeroallergen immunoblotting of exposed Burkard tape segments, the detected allergen spots showed a significant correlation with airborne pollen count recorded. The pollen extract elicited loss of IgE reactivity when treated with reducing agent-like beta-mercaptoethanol and heat, but showed six IgE-reactive components in nonreducing IgE-immunoblot. The fraction 1 eluted from Sephacryl S-200 column showed highest IgE reactivity and resolved into five major components in RP-HPLC. Out of these, the fraction showing optimum IgE reactivity in IgE-ELISA inhibition and immunoblotting with patient antisera, elicited esterase activity and found to be a homogenous protein of 100 kDa.

CONCLUSION

Carica papaya tree contributes significantly to the aeropollen and aeroallergen load of the suburban outskirts of Calcutta metropolis, India. The pollen extract contains an important IgE-reactive protein component of 100 kDa molecular weight with esterase activity.

A study on the polymicrobial etiology of root canal infections in anterior non-vital teeth in a government hospital in Kolkata, India

A total of 52 patients having non-vital anterior teeth who attended at the Department of Conservative Dentistry of a Government Dental College of the city of Kolkata, India where studied for isolation of different microflora in the root canals of the non-vital teeth. 41 (78.8%) out of 52 cases studied showed the presence of microorganisms in the root canal of the teeth. A total of 83 different strains were isolated. The anaerobic organisms constituted 30.1% of the total isolates. 51.7% of the root canals showed presence of polymicrobial etiology of the non-vital teeth.

Cronkhite-Canada syndrome with adenomatous and carcinomatous transformation of colonic polyp

We describe a 70-year-old woman who presented with watery diarrhea and was found to have gastric and colonic polyposis, cutaneous hyperpigmentation, alopecia and onychodystrophy (Cronkhite-Canada syndrome). Histology of a polyp from the stomach showed features of juvenile or retention type (hamartomatous) polyp. One colonic polyp revealed features of tubular adenoma, with moderate dysplasia. Another large pedunculated colonic polyp showed a tubulovillous adenoma with a focus of well-differentiated adenocarcinoma confined to the submucosa of the stalk. Adenomatous and carcinomatous epithelial changes can occur in Cronkhite-Canada syndrome.

Evaluation of in vitro and in vivo antibacterial activity of dobutamine hydrochloride

PURPOSE

To determine the in vitro and in vivo antibacterial activity of a cardiovascular drug dobutamine hydrochloride.

METHODS

The minimum inhibitory concentration (MIC) of dobutamine was determined both by agar and broth dilution methods against 331 strains of bacteria from three gram positive and 13 gram negative genera. The antibacterial action of dobutamine was further tested in animal models.

RESULTS

Dobutamine was seen to possess powerful inhibitory action (5-200mg/mL) against most test bacteria in in vitro studies. It was bacteriostatic in nature. In vivo studies showed that the drug offered significant protection (p< 0.001) to mice challenged with a virulent bacterium.

CONCLUSION

Dobutamine showed remarkable antibacterial property against several pathogenic bacteria. Its potential as an antibacterial agent may be confirmed after further pharmacological studies.

Massive hepatomegaly: a presenting manifestation of multiple myeloma

We report a 50-year-old woman presenting with isolated massive hepatomegaly. Liver histology showed dilated sinusoids within which some atypical cells, probably of hematopoeitic origin, were identified. Bone marrow was densely packed with similar atypical cells with high nucleo-cytoplasmic ratio, which tested positive for plasma cell markers. Plasma protein electrophoresis showed a distinct M spike in the gamma globulin fraction and skeletal survey revealed multiple lytic lesions in the skull and pelvic bones. Thus, a final diagnosis of multiple myeloma was made. The patient has received six cycles of chemotherapy and is doing well.

Binding of globular proteins to DNA from surface tension measurement

Extent of binding (gammap) of globular proteins to calf-thymus DNA have been measured in mole per mole of nucleotide as function of equilibrium protein concentration. We have exploited measurement of the surface tension of the protein solution in the presence and absence of DNA to calculate the binding ration (gammap). Interaction of bovine serum albumin with DNA has been studied at different pH. Interaction of bovine serum albumin with DNA has been studied at different pH, ionic strength and in presence of Ca2+. Interaction of BSA with denatured DNA has also been investigated. Binding isotherms for other globular proteins like beta-lactoglobulin, alpha-lactalbumin and lysozyme have been compared under identical physicochemical condition. It has been noted with considerable interest that globular form of protein is important to some extent in protein-DNA interaction. An attempt has been made to explain the significance of difference in binding ratios of these two biopolymers in aqueous medium for different systems in the light of electrostatic and hydrophobic effects. Values of maximum binding ration (gammap(m)) at saturated level for different systems have been also presented. The Gibb's free energy decrease (-deltaG0) of the binding of proteins to DNA has been compared more precisely for the saturation of binding sites in the DNA with the change of activity of protein in solution from zero to unity in the rational mole fraction scale.

Modulation of macrophage mannose receptor affects the uptake of virulent and avirulent Leishmania donovani promastigotes

The effect of oxidants and the anti-inflammatory steroid dexamethasone on the attachment and internalization of virulent and avirulent Leishmania donovani promastigotes by the macrophage mannosyl fucosyl receptor was examined. Oxidants and dexamethasone are known to down- and upregulate the expression of the mannose receptor. Macrophages, when treated with 500 microM H2O2 at 37 C for 30 min, stimulate about 45% inhibition in uptake of an avirulent strain (UR6), and 30 and 25% inhibition for virulent strains AG-83 and GE-I, respectively. Treatment of macrophages with dexamethasone for 20 hr resulted in a stimulation in uptake of the parasite. When UR6 was used, a 3-fold increase in uptake was observed compared with the controls. Parasite uptake was also inhibited by the H2O2-generating system, glucose/glucose oxidase; inhibition was blocked by catalase. Treatment of macrophages either with H2O2 or dexamethasone did not affect the binding of the advanced glycosylation end product-bovine serum albumin (AGE-BSA), the ligand for AGE receptor of macrophages. Similarly, indirect evidence also shows that both types 1 and 3 complement receptors (CR1, CR3) are not affected by these treatments, indicating that, besides the mannosyl fucosyl receptor, other receptors are minimally altered in the identified condition. These results suggest that the up- and downregulation of the mannose receptor of macrophages may play a role in affecting L. donovani infection.

G-protein-mediated signaling and its control in macrophages and mammalian cells

G-protein coupled receptor (GPCR) in various cell types exert its effects through heterotrimetic GTP-binding proteins (G-proteins). The interaction of specific ligand or agonists with CPCR transuces signal and enhances gene expression, mitogen activated protein kinase (MAP kinase) activation, and thus regulates cell proliferation, differentation, and motility. Abnormal signaling or prolonged activation of G-protein signaling pathways blocks normal functioning of various cells and tissues of our body. New insights into the mechanisms governing the specificity and temporal regulation of G-protein signaling pathways have been provided by the recent discovery of GTPase-activating proteins (GAPs) and RGS proteins (regulators of G-protein signaling). Different molecular biological approaches are now being employed to study the G-protein-mediated signaling and its control in various mammalian cells. Recent developments on the activation of phagocytic cells, especially macrophages, via ligation or cross-linking of GPCR and their postreceptor ligation effect against several intramacrophage pathogens are also discussed.

Biogeochemical cycling bacteria as indices of pond fertilization: importance of CNP ratios of input fertilizers

AIMS

The influence of carbon-nitrogen and nitrogen-phosphorus ratios of input fertilizers, and that of pond water, on the growth of heterotrophic and phosphate-solubilizing bacteria of water and sediment, was examined in relation to fertilizer mineralization indices using different modes of fertilization through inorganic and organic sources.

METHODS AND RESULTS

The first experiment used carbon-nitrogen-phosphorus ratios varying from 12 : 2 : 1 to 151 : 6 : 1, applied at the rate of 0.043 g l(-1) week(-1), whereas in the second ratios varied from 25.6 : 6.2 : 1 to 150 : 12 : 1 applied once at the rate of 3.33 g l(-1). Different fertilizers (cattle dung, poultry droppings, urea, single superphosphate and starch) were mixed in different proportions to achieve the desired carbon-nitrogen-phosphorus ratio. The heterotrophic and phosphate-solubilizing populations were more responsive to an early manuring phase than later, implying that pond fertilization was microbiologically more dynamic in the earlier phase. The carbon-nitrogen and nitrogen-phosphorus ratios of 11.8 (88.6 : 7.5) and 7.5 (7.5 : 1), respectively, of input fertilizers favoured growth of both heterotrophic and phosphate-solubilizing bacterial populations much better than the other ratios tested. Likewise, water carbon-nitrogen and nitrogen-phosphorus ratios of 11.9 and 3.34 induced bacterial growth. The carbon-nitrogen ratios of 12.63 (101 : 8) (input fertilizer)-4.54 (water), and nitrogen-phosphorus ratios of 8 (8 : 1) (input fertilizer)-2.93 (water), gave gross primary productivity values higher than the remaining ratios, exhibiting overall curvilinear relationships. The values of gross primary productivity were the direct function of values of fertilizer mineralization indices for carbon, nitrogen and phosphorus.

CONCLUSION

It is concluded that the mixed fertilizer (carbon-nitrogen-phosphorus-88.6 : 7.5 : 1) comprising cattle dung (95%), poultry droppings (2.5%), urea (2%) and single superphosphate (0.5%), applied at the rate of 23,000 kg ha(-1) year(-1), was a suitable cost-effective fertilization option for aquaculture practices.

SIGNIFICANCE AND IMPACT OF THE STUDY

As chemical fertilizers are expensive and cause some adverse effects on the soil structure, composition, microflora and other characteristics of the pond, mixed combinations of inorganic and organics with narrow range of carbon-nitrogen-phosphorus ratio can be suitable and cost-effective fertilization tools in aquaculture practices, which is to be linked with the microbial activities of the pond.

Training of providers in embryo transfer: what is the minimum number of transfers required for proficiency?

BACKGROUND

Embryo transfer represents one of the most critical procedures in the practice of assisted reproduction. The objective of this study was to identify retrospectively the minimum number of embryo transfers required to train providers properly in this skill.

METHODS AND RESULTS

The study group consisted of 204 patients who received embryo transfers between January 1996 and March 2000 in a university-based programme of assisted reproduction. The main outcome measure was clinical pregnancies per embryo transfer. Five Fellow trainees performed a total of 204 embryo transfers for an overall pregnancy rate of 45.5% per embryo transfer (93/204). In comparison, the programme pregnancy rate per transfer for experienced providers was 47.3% (560/1179). A chronological graph of each individual trainee's experience for the first 50 embryo transfers performed suggested a lower initial pregnancy rate for three of the five trainees. To determine whether a learning curve might exist, results of the first 25 transfers were compared as a subgroup with the second 25 transfers. Pregnancy rates were lower for the 1-25 transfer subgroup than in the 26-50 subgroup for three of the five Fellow trainees, although the difference was not statistically significant.

CONCLUSION

Clinical pregnancy rates of Fellows-in-training were indistinguishable statistically from those of experienced staff by 50 transfers.

Differences in concentrations of allergenic pollens and spores at different heights on an agricultural farm in West Bengal, India

The aim of the study was to assess the vertical profile of the major airborne pollen and spore concentration in the lower heights (up to six meters) and to check their allergenic potential causing respiratory allergy in agricultural workers. The study was conducted using rotorod samplers mounted at different heights at weekly intervals for two consecutive years (November 1997-October 1999). The major pollen grains and fungal spores (from mass culture) were collected in bulk and studied by skin-prick tests to detect allergenicity. Of the recorded pollen, 10 major and perennial types (e.g., Poaceae, Cheno-Amaranthaceae, Cyperaceae, Areca, etc.) were considered for comparative analyses. The tree pollen count showed more or less good correlation with increasing heights, whereas herb/shrub members are dominant at lower heights during all the three seasons (winter, summer and rains). The 10 major and perennial fungal spore types included Aspergilli group, Cladosporium, Nigrospora, etc. The smaller spores were dominant at greater heights and larger spores and conidia were more prevalent at lower levels. The total spore count was higher just after the rainy season during winter. In terms of allergenicity, Saccharum officinarum (sugar cane) of Poaceae, showed highest reactivity (70.58%) in skin test carried out in 189 adult agricultural field workers with respiratory disorders living inside the study area. Among fungal spores, Aspergillus japonicus was the strongest allergen, evoking 74.07% positive reactions. Drechslera oryzae, the pathogen causing brown spot of rice was also found to be a potent allergen.

fMLP receptor stimulated activation of macrophage: its effect on killing of intracellular Leishmania donovani

The fMLP receptor of peritoneal macrophages stimulated by fMLP grafted liposomes as ligand, was analysed and compared with respective controls for its ability to promote killing of intracellular Leishmania parasites. fMLP grafted liposomes show greater efficacy in killing intracellular L. donovani (MHOM/IN/1983/AG83) parasites in a time dependent manner than free fMLP. fMLP grafted liposomes also release more active oxygen intermediates and reactive nitrogen intermediates (O2-, H2O2, NO) than free fMLP. The key enzymes PKC and PTK for the respiratory burst and nitric oxide generation were found to be important in this fMLP receptor mediated signaling process as the enzyme specific inhibitors viz. staurosporine, genistein and AG126 suppressed the leishmanicidal effect of fMLP grafted liposomes. The above findings suggest that the fMLP receptor of macrophages activates PKC and PTK mediated signalling that is responsible for the intracellular parasite killing.

Ligation of Fc receptor of macrophages stimulates protein kinase C and anti-leishmanial activity

Fc receptors are known to express on the surface of mature monocytes, macrophages and lymphocytes. In this study a ligand e.g. liposomal IgG (human IgG coupled to PE-liposome via carbodimide reaction) was developed to ligate the Fc receptor of macrophages. When liposomal IgG was incubated with macrophages at 37 degrees C for 5 min, it induced the macrophage activation which suppress the parasite burden approximately to an extent of 60%, 50% and 45%, when macrophages were infected with UR6, AG83 and GE1 strains of L-donovani respectively. Superior efficacy of liposomal IgG were achieved compared to the treatment with free IgG and free liposomes. The activity of protein kinase C (PKC) has been found to be higher in the Fc receptor targeted macrophage membrane fraction, suggesting its translocation from the cytosol. Staurosporine, a potent inhibitor of the enzyme protein kinase C (PKC) has been found to protect the parasite inside the macrophage indicating the role of PKC in the signaling process. The liposomal IgG treatment has been found to induce the generation of significant amount of superoxide and hydrogen peroxide which helped to suppress the parasite burden. Further when liposomal IgG were incubated with IFN-gamma primed, LPS activated macrophages, a significant amount of NO release was also noticed, indicating its role in parasite killing. The above results suggest that Fc receptor mediated activation by liposomal IgG may be used as an alternative approach to kill parasites intracellularly.

Evaluation of sympathetic nerve terminals with [(11)C]epinephrine and [(11)C]hydroxyephedrine and positron emission tomography

BACKGROUND

The goal of the present study was to directly compare the new radiopharmaceutical agent [(11)C]epinephrine (EPI) with [(11)C]hydroxyephedrine (HED) through the use of PET.

METHODS AND RESULTS

Seven healthy volunteers and 10 patients were investigated after heart transplantation. PET images of both tracers were of excellent quality in the volunteers. Values for radiolabeled metabolites (measured in percent of blood activity) at 5, 20, and 60 minutes after injection were approximately 35%, approximately 82%, and approximately 86% for EPI and approximately 13%, approximately 47%, and approximately 78% for HED, respectively. At 35 minutes, metabolite-corrected mean myocardial retention fraction of EPI (0. 235+/-0.022 min(-1)) was significantly greater (P<0.01) than that of HED (0.142+/-0.012 min(-1)). Corrected tracer retention fractions of both EPI and HED were significantly reduced in transplant recipients (0.055+/-0.004 min(-1), P<0.0001; and 0.050+/-0.006 min(-1), P<0. 0001, respectively) compared with volunteers. Normalization of retention fractions of patients with transplantation within 1 year to volunteers resulted in a value (ratio expressed in percent) of 20. 6+/-1.8% for EPI, significantly (P<0.03) smaller than 27.8+/-0.8% for HED. In patients with transplantation later than 1 year, the values were 26.0+/-2.9% for EPI compared with 44.2+/-5.6% for HED (P<0.014).

CONCLUSIONS

Both tracers showed high selectivity for neuronal uptake in the heart, with a significant reduction in tracer retention in transplant recipients compared with volunteers. Compared with HED, EPI showed greater retention in volunteers and a lower retention ratio in transplant recipients, suggesting that EPI may be the superior tracer with higher sensitivity to neuronal abnormalities. Because EPI reflects neuronal uptake, metabolism, and storage, it may be more suitable for the study of neuronal integrity than HED, which primarily traces uptake-1 capacity.

Macrophage protein kinase C: its role in modulating membrane microviscosity and superoxide in leishmanial infection

Pretreatment of macrophages with, an agonist of PKC, showed diverse effects on degradation and survival of two virulent strains of Leishmania donovani promastigotes. Treatment of macrophages with PMA for 45 min at 37 degrees C generated significant amounts of superoxide anions and reduced the parasite burden of macrophages by up to 48 and 43% when AG83 and GE-1 strains were used for infection. Staurosporine, an inhibitor of PKC, inhibited PMA-dependent killing of the parasites, while tyrphostin AG 126, an inhibitor of protein tyrosine kinase, showed very little effect. Depletion of PKC by prolonged incubation with PMA drastically reduced the superoxide anion generation and increased the uptake and multiplication of the parasites. Finally, to understand the mechanism of higher uptake of the parasites by PKC-depleted macrophages, membrane microviscosity was measured by fluorescence depolarization. Membrane microviscosity was found to be approximately 40% lower in PKC-depleted macrophages than in normal macrophages, indicating the role of membrane fluidity in the infection process. Together, these data suggest PKC activation, superoxide generation, and membrane fluidity are essential factors in the efficient regulation of leishmanial infection.

Clinicoimmunologic studies on Phoenix sylvestris Roxb. pollen: an aeroallergen from Calcutta, India

BACKGROUND

This study highlights the allergenicity and allergenic components of the pollen of Phoenix sylvestris Roxb. (PS), or date sugar palm, which is predominantly airborne in the air of Greater Calcutta.

METHODS

A 2-year aerobiologic survey was performed by Burkard sampler. PS pollen extract was used in skin tests of allergic patients, fractionated by (NH4)2SO4 and the Sephacryl S-200 column. The allergenicity of each fraction was checked by skin test and IgE ELISA inhibition. The principal allergenic fraction, Fr.lla, was separated in 11% SDS-PAGE, and its allergenicity was confirmed by IgE ELISA inhibition and immunoblotting.

RESULTS

PS pollen grains were found to be prevalent in the air of the suburban zone of Calcutta from January to March with a peak in February. The pollen extract showed high (44.07%) positive skin reaction on 540 respiratory allergic patients. Among the (NH4)2SO4 cut fractions, Fr.II was the most active one, and it was resolved into four subfractions in the Sephacryl S-200 column. Fr.lla was the principal allergenic fraction, showing the presence of two components of 33 and 66 kDa in SDS-PAGE. In IgE immunoblotting, both of the components were found to be allergenic.

CONCLUSIONS

The PS pollen grain is an important aeroallergen from Calcutta, India. The 33- and 66-kDa components are the major allergens present in the relevant pollen extract.

Antigenic relationship between four airborne palm pollen grains from Calcutta, India

The pollen grains of Areca catechu, Borassus flabellifer, Cocos nucifera and Phoenix sylvestris, all belonging to the family Aracaceae (Palmae), are airborne and found to be potent in causing human respiratory allergy. The present study was undertaken to discover the antigenic relationship, if any, in the four relevant palm pollen grains. The study was conducted by using Borassus and Phoenix antisera raised in rabbit. These antisera were used in rabbit IgG specific ELISA-inhibition and rocket immunoelectro-phoresis (RIE) assays for all four palm pollen extracts. In ELISA-inhibition, a distinct inhibition was obtained with comparable amount of soluble pollen protein. The RIE precipitin bands also revealed the presence of common antigenic components in the palm pollen. After isolation and purification, such common antigens may be useful in allergen immunotherapy in asthmatics.

Clinical and bacteriological profile of neonatal infections in metropolitan city based medical college nursery

Out of 6319 live born babies, 310 (4.9%) with high risk factors and with clinical suspicion of sepsis were studied for incidence pattern of neonatal infections. Incidence of neonatal infection was 2.56% in normal weight babies and 8.42% in low birth weight babies. Total culture positivity was 48.38%. Klebsiella was the most frequent offender, followed by Staph aureus and Staph epidermidis. Majority of klebsiella species were sensitive to ceftriaxone (86%), amikacin (84%) and ceftazidime (80%). Ceftriaxone was effective against Staph aureus (95%) and Staph epidermidis (95%). Overall fatality was 17.1%, distinctly higher in low birth weight group (22.06%) than normal weight group (6.18%).

Allergenic relationship among four common and dominant airborne palm pollen grains from Eastern India

BACKGROUND

Palm pollen grains are predominant aeroallergens in the tropics including India. Evidence of allergenic crossreactivity had been reported from various parts of the world on different families, e.g. Poaceae, Asteraceae, etc. No such information is available about the palm pollen of tropical countries.

OBJECTIVES

The present study was undertaken to find out the allergenic relationship, if any, in four common and important palm pollen in India.

METHODS

A 2-year aerobiological survey was carried out at Madhyamgram situated at the suburban fringe of Calcutta Metropolis using Burkard volumetric sampler to know the seasonal variation of Areca catechu, Borassus flabellifer, Cocos nucifera and Phoenix sylvestris among others. Skin-prick tests (SPT) were performed with the relevant pollen extracts on the respiratory allergic patients. Sera from the subjects were tested directly by ELISA for estimating the allergen specific IgE. ELISA inhibitions and dot blotting were performed with pooled patients sera and four palm pollen extracts to detect the cross-reactivity.

RESULTS

Among 70 patients, Areca catechu exhibited the maximum percentage (48.5%) of positive responses followed by Cocos nucifera (45.7%), Phoenix sylvestris (42.85%) and Borassus flabellifer (38.5%). On an average, 30-50% of the patients showed positive skin reactions and enhanced specific IgE level to more than one palm pollen extract. Further evidence of allergenic crossreactivity among the four palm pollen grains were provided by dot blotting and ELISA inhibition studies. In ELISA inhibition, a distinct inhibition was obtained with comparable amounts of the pollen extracts.

CONCLUSION

The suburban aerobiological survey of Calcutta and SPT results confirmed that the relevant pollen types are significant contributors of aeroallergen load of the study area. ELISA inhibition studies with the pooled patients sera using antihuman IgE probe revealed the presence of shared allergenic components among the four palm pollen grains.

Macrophage mannosyl fucosyl receptor: its role in invasion of virulent and avirulent L. donovani promastigotes

The interaction of leishmania parasites with macrophages is known to be receptor mediated. Previous study from this laboratory (J. Parasitol. 82:632, 1996) showed the significant involvement of LPG and gp63 receptors in the recognition of virulent strains onto the macrophages. The role of carbohydrate receptors the other major receptors besides LPG and gp63 receptors, in the recognition of both virulent (strains AG83 and GE1) and avirulent (strain UR6) leishmania onto the host macrophages has been the major focus of the present investigation. Various neoglycoproteins were used as efficient ligands to preblock the carbohydrate receptors on the macrophage surface. Similarly, various sugar specific lectins were used to preblock the corresponding carbohydrate ligands on the parasite surface. When these preblocked macrophages or parasites were used to study their mode of recognition, it was obvious from the findings that avirulent leishmania promastigotes possibly use the mannosyl fucosyl receptors (MFR) more avidly for their initial attachment and subsequent internalization into the macrophages whereas the virulent leishmania exhibits limited use of this receptor. When a macrophage-like cell line (J774), lacking in MFR, was purposely selected to test the previous findings, as expected, the attachment of avirulent promastigotes (UR6) onto the cell line was found to be negligible when compared to the peritoneal macrophages. Thus, it appears that avirulent leishmania promastigotes probably utilize MFR significantly for their initial recognition and subsequent internalization by macrophages.

Aerobiologic and immunochemical studies on Borassus flabellifer pollen: evidence for a 90-kD allergen

BACKGROUND

The pollen grains of Arecaceae have been proved to be a very common aeroallergen in India. Except for the pollen grains of Cocos nucifera, detailed information about the allergenicity of other dominant Indian palm pollen is not available.

OBJECTIVES

To explore the aerobiologic and allergenic significance of the pollen of palmyra palm (Borassus flabellifer Linn.), one of the important and common palm trees in India, with a view to isolate and purify its major allergenic components.

METHODS

The aerobiologic survey was performed continuously using Burkard volumetric and Rotorod samplers from July, 1994 to June, 1996 in a northern suburb of greater Calcutta. The allergenic potential of the pollen extract and different fractions were studied by skin prick tests (SPT). ELISA and ELISA inhibition experiments were performed with individual and pooled patient sera to detect the specific IgE level. By 2-step ammonium sulphate fractionation and gel filtration study, the allergic fraction Fr.IIA1 was isolated. Its molecular weight was determined by SDS-PAGE and homogeneity was confirmed by rocket and crossed immunoelectrophoresis using rabbit antisera.

RESULTS

Pollen grains of B. flabellifer were found to be present in air from February to May and June contributing more than 7% of the total airborne pollen load of the study area. The pollen elicited maximum concentration at 19 to 20 hours in the evening and at a height of 4 m from ground level. Skin prick testing of 455 respiratory allergic patients with whole pollen extract exhibited 31.64% positive response. After 2-step ammonium sulphate fraction and gel filtration, a fraction (Fr.IIA1) having remarkable allergenicity was isolated. In native and SDS-PAGE, it was found as a single protein component of 90 kD and as homogeneous in RIE and CIE. The soluble protein-carbohydrate analysis indicated the probability of the component to be a glycoprotein.

CONCLUSION

The aerobiologic, clinical, and immunochemical, studies demonstrated that the pollen of B. flabellifer is a dominant aeroallergen to cause respiratory trouble in the area where these trees grow. The isolated 90-kD component is one of the major allergens present in the pollen extract.