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Biomedical subjects

J Verma

Publications and source records attributed to J Verma.

At least 19 recordsLinked to original sources
PubMed2004

Effect of graded levels of aflatoxin, ochratoxin and their combinations on the performance and immune response of broilers.

1. The effects of dietary aflatoxin (AF, 0.5, 1.0 and 2.0 mg/kg), ochratoxin (OA, 1.0, 2.0 and 4.0 mg/kg) or combinations of these on body weight gain, feed efficiency, organ weights and immune response were studied in broilers. 2. Significant growth depression, reduced food consumption and poor food conversion efficiency were recorded in broilers fed a diet containing the greater concentrations of AF (1 and 2 mg/kg) and OA (2 and 4 mg/kg). 3. The combination of 2 mg/kg AF and 4 mg/kg OA exerted the maximum adverse effect on growth, feed intake and feed efficiency, indicating a synergistic effect on performance. 4. AF at 2 mg/kg in the diet caused a significant increase in the relative weight of liver, whereas the relative weight of kidney was significantly increased at 4 mg/kg of OA. A significant decrease in the relative weight of the bursa of Fabricius was noted at the highest concentration of AF (2 mg/kg) and combinations of 1 and 2 mg/kg AF and 2 and 4 mg/kg OA. 5. Cell mediated immunity (CMI), in terms of mean skin thickness (MST) sensitive to dinitrochlorobenzene (DNCB), was significantly reduced in chicks given the combination of 2 mg/kg AF and 4 mg/kg OA. Haemagglutination (HA) titre against sheep red blood cells (SRBCs) peaked at 42 d of age. At 42 and 47 d of age, a significant decrease in HA titres was recorded in chicks given 4 mg/kg OA or a combination of AF (1 or 2 mg/kg) and OA (2 or 4 mg/kg). 6. AF at a dietary concentration of 1 mg/kg or more and OA at 2 mg/kg or more, either alone or in combination, caused severe reductions in growth and immune response.

Aflatoxins↗
PubMed2001

Fusarium solani major allergen peptide IV-1 binds IgE but does not release histamine.

BACKGROUND: Fusarium solani (FS) is an important allergen source afflicting 4% of the nasobronchial allergy patients. Fus s I3596*, a 65 kDa major glycoprotein allergen of FS reacts with 95% fungus sensitive patients. OBJECTIVES: To purify and characterize a potent peptide from Fus s I3596* which may be useful for therapeutic purposes. METHODS: The 65 kDa protein was sequentially cleaved with trypsin and cyanogen bromide (CNBr). The cleaved products were purified on reverse phase high performance liquid chromatography (rpHPLC) column and functionally characterized by in vitro and in vivo methods for its IgE binding and histamine release. RESULTS: The protein on cleavage showed 11 peaks (I to XI). Of these, peaks I, III, IV and V were highly allergenic as determined by IgE ELISA. These peaks were further purified and peptide IV-1 was most potent in comparison to other peptides by ELISA-inhibition. This peptide showed IgE binding but could not evoke intradermal response in Fusarium-sensitive patients. Heparinized blood challenged with peptide IV-1 does not release histamine. Preincubation of heparinized blood with peptide IV-1 and challenging with crude extract blocked histamine release in a dose dependent manner. CONCLUSION: Peptide IV-1 binds to IgE but does not release histamine, demonstrating its potential use in therapy of Fusarium-allergic patients.

Adult↗
PubMed2001

Prevalence of hepatopulmonary syndrome in cirrhosis and extrahepatic portal venous obstruction.

OBJECTIVE: Hepatopulmonary syndrome (HPS) is characterized by arterial hypoxemia in patients with chronic liver disease caused by abnormal intrapulmonary vasodilations. Data on its frequency vary from 5% to 29%. Most of these studies are from the West and in patients with cirrhosis. We, therefore, studied the prevalence of HPS in patients with liver cirrhosis and extrahepatic portal venous obstruction (EHPVO). METHODS: We studied 54 consecutive patients with liver cirrhosis (42 men and 12 women; mean age = 44.2 +/- 13 yr; Child grade A: 13, B: 22, and C: 19) and 50 patients with EHPVO (31 men and 19 women; mean age = 23.3 +/- 7.8 yr) Diagnosis of cirrhosis was made by history, liver function abnormalities, endoscopy, and sonography, whereas EHPVO was diagnosed by demonstration of a block in the splenoportovenous axis on sonography. Each of the patients underwent chest x-ray, arterial blood gas analysis, contrast-enhanced echocardiography (CEE), and pulmonary function tests. HPS was diagnosed in a patient with positive CEE, in the presence of hypoxia (PaO2 < 70 mm Hg) and/or elevated alveolar arterial oxygen gradient of > 20 mm Hg in the absence of any underlying cardiopulmonary disease. RESULTS: Ten of 54 patients (18.5%) with cirrhosis were positive on CEE compared with two of 50 patients (4%) with EHPVO. Six of the 10 patients positive with cirrhosis for CEE had associated hypoxia, whereas only one EHPVO patient with positive CEE had an elevated pulmonary alveolar arterial oxygen gradient of > 20 mm Hg. Thus, the incidence of HPS was 11.1% in patients with cirrhosis, compared with 2% in patients with EHPVO. One patient with HPS and cirrhosis had clinical cyanosis. CONCLUSION: HPS occurs more commonly in patients with cirrhosis but can also be seen in patients with EHPVO.

Adolescent↗
PubMed2000

Purification and partial characterization ofa 67-kD cross-react ive allergen from Imperata cylindrica pollen extract.

BACKGROUND: Grass pollens are known to induce type I allergic reactions in a large number of genetically predisposed individuals. Earlier studies have recognized Imperata cylindrica (Ic) pollen as an important source of aeroallergen which contained 7 IgE binding proteins in the MW range of 85-16 kD. OBJECTIVES: To isolate, purify and characterize a cross-reactive allergenic protein from Ic pollen extract for diagnosis and therapy of grass pollen allergy. METHODOLOGY: Ic pollen extract was fractionated using DEAE Sephadex A-50, Sephadex G-200 and Mono Q column. Allergenic activity of the fractions was checked by ELISA, skin tests, ELISA inhibition and immunoblot using sera of Ic-sensitive patients. A 67-kD protein was purified to homogeneity from Ic-VIII. The allergenic determinants of this protein were identified by SDS-PAGE and immunoblot after CNBr treatment. RESULTS: Among Ic fractions, Ic-VIII was highly potent by ELISA, skin tests and showed cross-reactivity with 4 other tropical grasses by immunoblot and ELISA inhibition. The subfraction Ic-VIIIe1 of Ic-VIII showed a band at 67 kD on SDS-PAGE. On CNBr treatment, it gave 7 peptides, 3 of which were found to be allergenic. CONCLUSION: A 67-kD protein (Ic-VIIIe1) was isolated, purified to homogeneity and partially characterized. It showed cross-reactivity with tropical grasses tested and contained at least three allergenic determinants.

Allergens↗
PubMed1998

Isolation and immunobiochemical characterization of a major allergen (65 kDa) from Fusarium equiseti.

Fusarium equiseti is one of the most important species in the class Deuteromycetes (Fungi Imperfecti). For proper diagnosis and immunotherapy, isolation and characterization of allergens of F. equiseti are necessary. In the present study, culture filtrate (CF) extract of F. equiseti was resolved into 35-37 bands on isoelectric focusing pI (3-9) and SDS-PAGE (mol. wt. 10-100 kDa). Most of them were glycoproteins, as identified by PAS staining. F. equiseti CF revealed 15 allergenic proteins on immunoblot with an allergic serum pool. It was fractionated into nine fractions (I-IX) on a Superose-12 column by FPLC. Fraction IV (65 kDa) and fraction VI (25 kDa) were found to be highly allergenic by IgE ELISA. A 65-kDa protein was observed as a major allergen because it was recognized by most of the patient sera on immunoblot. After elution from SDS-PAGE gel, it gave two bands of pI 7.4 and 6.0. Inhibition in IgE-binding components of F. equiseti CF with CF extracts of F. solani and F. moniliforme by immunoprint inhibition assay indicated the allergenicity shared between the extracts of Fusarium species. Data suggested that the 65-kDa is the major allergen in the Fusarium species and can be used for the treatment of allergic patients.

Allergens↗
PubMed1997

Immunobiochemical characterization of Putranjiva roxburghii pollen extract and cross-reactivity with Ricinus communis.

Putranjiva roxburghii (PR) pollen has been found to be an important aeroallergen for type I hypersensitivity. In the present study, the IgE binding proteins of PR pollen have been characterized and compared with pollen allergens of Ricinus communis (RC) belonging to family Euphorbiaceae. On isoelectric focusing, PR pollen extract resolved into 35 bands (pI 3-9), whereas SDS-PAGE separated it into 18 protein components (MW 14-100 kD). Pooled patient's sera (ID +ve to PR) recognized 12 allergenic proteins in Putranjiva and five of them (MWs 92, 80, 55, 43 and 30 kD) showed immunologic reactivity to most of the sera samples tested individually by immunoblot. A number of shared allergenic proteins (MWs 92, 80, 66, 50, 43 and 14 kD) were observed between PR and RC pollen extracts on immunoblot using Putranjiva allergic serum pool. Inhibition in the binding for most of PR pollen allergenic proteins was obtained with higher concentration of RC extract than PR itself, depicting the presence of cross-reacting allergens in both. Putranjiva pollen extract was fractionated by a combination of DEAE Sephadex-A 50 and Sephadex-G 200 column chromatography. Periodate deglycosylation of western blotted PR extract and Put I fraction indicated the involvement of carbohydrate moieties in the allergenic activity. Of the two fractions from Put I (Ia and Ib), Put Ib was found to be the most allergenic protein by ELISA inhibition. Dot blot analysis with individual patients sera identified it as a major allergen of PR.

Adolescent↗
PubMed1997

Inter-relationship of zinc levels in serum and semen in oligospermic infertile patients and fertile males.

Infertility is a problem affecting 10-12% of couples. Zinc is necessary for growth, sexual maturation and reproduction. Semen analysis is helpful in ascertaining the evidence of spermatogenesis, sperm transport, sperm quantity and quality and also provides clue to the functioning of the accessory glands i.e. seminal vesicles and prostate. The present study was conducted in 50 oligospermic infertile males and control group consisting of 25 normospermic known fertile males. Semen and Serum samples were obtained from each case in study as well as control group. Semen and serum were processed by wet ash method. The seminal and serum zinc levels of each case in study and control group were estimated. Statistically, serum zinc and semen zinc levels were significantly lower in infertile patients than fertile males. A significant correlation was observed between serum and semen zinc levels in study group.

Adult↗
PubMed1995

Studies on shared antigenic/allergenic components among fungi.

Fungal allergens have been found to be one of the most prevalent aeroallergens in India. Knowledge of shared/unique components among different fungi is necessary for proper diagnosis and treatment of patients allergic to fungi. In the present study, crude extracts (CE) of 11 common fungi (Alternaria alternata, Aspergillus flavus, Asp. fumigatus, Asp. niger, Asp. tamarii, Asp. versicolor, Cladosporium herbarum, Curvularia lunata, Mucor hiemalis, Penicillium citrinum, and Fusarium solani) were characterized by isoelectric focusing (IEF), SDS-PAGE, and immunoblot. On IEF (pI 3-9), the number of protein bands was found to be greatest (46) in M. hiemalis extract. SDS-PAGE exhibited a varied number of bands, generally 18-40, with mol. mass ranging from 14 to 100 kDa. IgG-specific immunoprint using rabbit anti-F. solani CF antibodies demonstrated a mol. mass distribution of shared antigenic proteins of 14-100 kDa in most of the fungi. Shared allergenicity was observed in a number of allergenic proteins in fungal extracts with mol. mass ranging between 14 and 70 kDa on IgE-specific immunoblot using pooled sera of patients allergic to Fusarium. A 45-kDa protein was found to be common among these fungi on immunoblot with patients as well as with rabbit antibodies. F. solani CF extract contained more antigenic/allergenic proteins than F. solani CE. It was concluded that F. solani CF shared several antigenic/allergenic components with CE of other common fungi. This fact needs to be taken into account when fungal extracts are used in diagnosis and immunotherapy of allergic patients.

Adolescent↗
PubMed1995

Immunobiochemical characterization of Brassica campestris pollen allergen.

Brassica campestris (BC), Eng. Mustard, is an important source of pollen allergen, responsible for type I hypersensitivity disorders. In the present study, BC pollen extract was characterized by TLIEF, SDS-PAGE and immunoprinting. The extract separated into 50 silver stained bands of pI 3-9 on isoelectric focusing whereas it resolved into 14 Coomassie blue stained protein bands of 14-100 kD on SDS-PAGE. Immunoblot analysis with individual patient sera detected four allergenic proteins of 90, 67, 60 and 14 kD. BC separated into 8 peaks (Bras 1-8) on DEAE Sephadex A-50 column. Bras 2 was found to be most potent by IgE specific ELISA, hence further fractionated on Sephadex G-200. A protein of 90 kD (Bras 2a) isolated by gel filtration was found to be most allergenic protein by ELISA inhibition. The findings shall be applicable in standardization of future batches of BC pollen extract to be used for allergy diagnosis and immunotherapy.

Allergens↗
PubMed1995

Antigenic and allergenic relationships among airborne grass pollens in India.

BACKGROUND: Pollen from grasses (Poaceae) are predominant aeroallergens throughout the world including tropical countries. Studies from USA, Europe, and Australia have shown extensive allergenic/antigenic cross reactivity among the grass pollen allergens prevalent there. No such information is available about airborne grass pollens of tropical countries. OBJECTIVE: The present study was undertaken to explore common antigenic/allergenic components, if any, of five important grass pollens of India. METHODS: Intradermal tests (ID) were performed with pollen extracts of Cenchrus, Cynodon, Imperata, Pennisetum, and Sorghum in patients with nasobronchial allergy. ELISAs were performed for estimating the allergen-specific IgE in sera of patients eliciting markedly positive ID response (2+ to 4+). To detect cross reactivity, ELISA inhibition experiments were carried out using pooled patient sera and five grasses, individually, as inhibitors with different solid phase antigens. To evaluate common antigenic components in Cenchrus, Imperata, and Pennisetum pollen extracts, rocket immunoelectrophoresis (RIE) and ELISA inhibition were conducted using rabbit antisera. RESULTS: Among 133 patients, Cynodon extract elicited markedly positive skin reactivity in most patients followed by Pennisetum, Imperata, Cenchrus, and Sorghum. A large number of patients showed markedly positive skin reactions and enhanced specific IgE levels to more than one grass pollen extract. ELISA inhibition experiments showed different degrees of cross reactivity among the grass pollens studied. Rocket immunoelectrophoresis and ELISA inhibition using rabbit antisera with homologous and heterologous pollen revealed the presence of shared antigenic components in Cenchrus, Imperata, and Pennisetum extracts. CONCLUSION: The varied dose-response curves obtained with ELISA inhibition using different inhibitors suggest the presence of both common and specific antigens/allergens in the grass pollens studied. Based on the extensive immunologic cross reactivity, among the tropical grass species, it may be possible to use mixed allergen preparations for allergy diagnosis and immunotherapy.

Allergens↗
PubMed1994

Purification and characterization of Fus sI3596*, a 65 kd allergen of Fusarium solani.

A component of Fusarium solani (F. solani), identified as the major allergen, Fus sI3596* was purified to homogeneity from culture filtrate (CF) by means of anion-exchange column chromatography, gel filtration and FPLC. The homogeneity of Fus sI3596* was assessed by IEF, PAGE, SDS-PAGE (non-reducing), immunoblot and HPLC. Fus sI3596* was isolated as a glycoprotein of MW 65 kd and pI 3.6. The IgE ELISA-inhibition assay after periodate treatment of the fraction showed a lower IgE binding capacity suggesting involvement of carbohydrate moiety in IgE binding reactions of the allergen. Peptide fragments of Fus sI3596* obtained after CNBr and trypsin treatment were analysed by immunoblotting for their allergenicity. This study indicated that there could be at least 3 allergenic determinants in the major allergen, Fus sI3596* of F. solani CF.

Allergens↗
PubMed1994

Studies on Fusarium solani. Cross-reactivity among Fusarium species.

Allergenic cross-reactivity among three Fusarium species (F. solani, F. equiseti, and F. moniliforme) was determined by crossed immunoelectrophoresis (CIE), ELISA inhibition, and immunoprint-inhibition analysis. Inhibiting immunoprint was used to assess the cross-reactivity of individual allergenic proteins in culture filtrate (CF), separated on SDS-PAGE. Dose-response inhibition of band 14 kDa in immunoprints of F. solani CF by antigens of F. solani CF, F. equiseti CF, and F. moniliforme CF demonstrated significant cross-reactivity of allergenic proteins on analysis of densitometric scans. CIE and ELISA inhibition using hyperimmune sera raised in rabbits against F. solani CF antigen also demonstrated shared antigenicity among Fusarium species. Collectively, this study revealed the presence of shared as well as unique antigenic and allergenic determinants in F. solani CF, F. equiseti CF, and F. moniliforme CF antigens.

Allergens↗
PubMed1994

Fusarium solani: immunochemical characterization of allergens.

Allergenic components of the fungus Fusarium solani were isolated using (NH4)2SO4 precipitation and ion-exchange column chromatography. The allergenicity of fractions was studied by enzyme-linked immunosorbent assay and radioallergosorbent test inhibition techniques. Proteins of culture filtrate (CF), mycelium (MY), and spore (SP) extracts of F. solani were characterized by isoelectrofocusing, sodium dodecyl sulphate-polyacrylamide gel electrophoresis, and IgE-specific immunoblotting. CF antigen of F. solani contained more allergenic proteins than MY and SP, visible on immunoblot analysis using allergenic serum pool. A 65-kD protein component of CF was found to be a major allergen, as it was strongly visible on immunoblots of all 15 patient sera tested. Crossed immunoelectrophoresis and enzyme-linked immunosorbent assay inhibition using rabbit antibodies raised against F. solani CF demonstrated shared antigenicity between CF, MY, and SP extracts. It was observed that F. solani is a significant allergen, and most of the allergens of MY and SP extracts were found in CF extract. Therefore, CF alone can be used in the preparation of a standard extract. However, few unique allergenic proteins were observed in MY as well as in SP extracts of F. solani. Hence, the use of combined CF, MY, and SP extracts of F. solani is recommended for diagnosis and immunotherapy.

Adolescent↗
PubMed1992

A study on antigenic and allergenic changes during storage in three different biological extracts.

The stability of three allergens common in tropical countries was evaluated under different storage conditions. Prosopis juliflora (PJ), Rhizopus nigricans (RN), and wheat dust (WD), were taken as representatives of various groups of allergens viz, pollen, fungi and dust. The extracts were stored in buffer containing phenol (0.4%) or glycerol (50%) at temperatures ranging from 4-55 degrees C for 15 to 60 days. Protein content of PJ extract was reduced remarkably when it was stored at 40 degrees C for 45 days. Thin layer isoelectric focusing and rocket immunoelectrophoresis of PJ showed that certain antigenic proteins degrade rapidly even at 25 degrees C as early as day 15. However, two to three proteins of PJ remain stable at a higher temperature (40 degrees C) for two months. Relative radioallergosorbent test (RAST) inhibition showed substantial loss of allergenic activity in all the three extracts, when stored at higher temperatures (25-55 degrees C) even for short durations, i.e., 15 days. Extracts (PJ and RN) containing 50% glycerol were found to be stable, retaining more than 50% activity, even when stored at 55 degrees C for 40 days, while extracts without glycerol lost more than 75% of their allergenic activity. However, addition of glycerol did not change the stability of wheat dust allergenic extract. The present findings indicate that allergenic extracts behave differently when stored. Hence, the stability of each extract should be determined individually.

Allergens↗