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Biomedical subjects

A Sen

Publications and source records attributed to A Sen.

At least 19 recordsLinked to original sources

Development of an indirect ELISA for the detection of antibodies against Peste-des-petits-ruminants virus in small ruminants.

Peste des petits ruminants (PPR) is an acute, febrile, highly contagious and economically important viral disease of small ruminants. A polyclonal antibody based indirect ELISA was developed for detection of antibodies to PPR virus in the serum samples of goats and sheep using purified PPR viral antigen propagated in Vero cell culture. A threshold (cut-off) value was set as twice the mean of the negative population based on the distribution of known negative serum samples in respect of PPR virus antibodies in the test. A total of 1544 serum samples from goats and sheep were screened by indirect ELISA and competitive ELISA. The indirect ELISA compared very well with competitive ELISA, with a high degree of specificity (95.09%) and sensitivity (90.81%). When compared with virus neutralization test, the present assay had 100% specificity and 80% sensitivity. With serum samples, the assay could clearly differentiate animals from the infected population from uninfected ones. These results suggest that the indirect ELISA may be a good alternative tool to competitive ELISA for seroepidemiological surveys.

Animals↗

Development and characterization of a stable vero cell line constitutively expressing Peste des petits ruminants virus (PPRV) hemagglutinin protein and its potential use as antigen in enzyme-linked immunosorbent assay for serosurveillance of PPRV.

We developed and characterized a stable Vero cell line constitutively expressing Peste des petits ruminants virus (PPRV) hemagglutinin (H) protein and assessed its potential use as diagnostic antigen in enzyme-linked immunosorbent assay (ELISA). PPRV H gene of the vaccine strain (Sungri-96) was amplified by reverse transcription (RT)-PCR, cloned into a eukaryotic expression vector (pTarget), and subsequently transfected and expressed in Vero cells. A stable Vero cell line was developed after 20 repeated passages by using G418 antibiotic selection pressure (400 to 600 microg/ml). The integration of PPRV H gene in the Vero cell genome and its genomic transcription were confirmed by PCR and RT-PCR assays, respectively, and the 70-kDa PPRV H protein was characterized by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and Western blotting. The recombinant protein reacted specifically with PPRV anti-H neutralizing monoclonal and polyclonal antibody in competitive, sandwich, and indirect ELISA, respectively, indicating that the native form of the protein was expressed. Evaluation of the protein in competitive ELISA and indirect ELISA vis a vis whole virus was done using 306 and 146 goat field serum samples, respectively; comparable results were obtained with high degrees of relative diagnostic specificity (93.53% and 100%, respectively) and sensitivity (99.04% and 79.16%, respectively). This study shows that the PPRV H protein could be a sustainable source of safe antigen in countries of nonendemicity without the need to handle infectious virus for serodiagnosis.

Animals↗

Effect of combined therapy with hyperbaric oxygen and antioxidant on infarct volume after permanent focal cerebral ischemia.

The aim of the present study was to evaluate the efficiency of combination of hyperbaric oxygen (HBO) and an antioxidant on permanent focal cerebral ischemia. Male Wistar rats underwent permanent middle cerebral artery occlusion (MCAO). Then, animals were randomly assigned to one of four groups: the control group (n=9) received no treatment, HBO group (n=9) was treated for 90 min at 2.5 absolute atmosphere for 3 days, the U-74389G group (n=8) received single U-74389G injection (3 mg/kg), the HBO + U-74389G group (n=8) received both HBO and U-74389G treatments. Treatments were initiated within the first 10 min after MCAO. After 3 days, the infarct volumes in rat brains were measured. The infarct ratios were 25.6+/-6.5 % for the control group, 21.9+/-6.4 % for the HBO group, 15.7+/-5.7 % for U-74389G group and 12.5+/-3.8 % for HBO + U74389G group. The infarct volumes were significantly reduced in rats treated with U-74389G (p<0.05) and combination therapy (p<0.05). HBO failed to reduce infarct volume significantly. We concluded that 1) U-74389G is more beneficial than HBO on permanent MCAO in rats, and 2) a combined therapy failed to significantly improve infarct volume more than either single treatment.

Animals↗

One-step multiplex RT-PCR assay for the detection of peste des petits ruminants virus in clinical samples.

A single-tube one-step multiplex RT-PCR was standardized to amplify both 337 bp and 191 bp fragments of N and M genes of peste des petits ruminants virus (PPRV), respectively, and only a 337 bp fragment of N gene of Rinderpest virus (RPV). The RT-PCR using purified viral RNA was easily adopted for direct detection of PPRV in clinical field samples and its differentiation from RPV. The amplified N and M gene products were confirmed to be PPRV- and RPV-specific by their size in 1.5% agarose gel and restriction analysis. In the assay, the Qiagen one-step RT-PCR kit containing the Ominiscript and Sensiscript reverse transcriptases and Hot star Taq DNA polymerase was utilized. The sensitivity of the assay was found to be 100 fg of PPRV RNA. Compared with a two-step assay, the one-step assay is easier and time-saving as it requires just a single buffer for both reactions, reverse transcription (RT) and PCR. In experimentally infected goats, PPRV was detectable by the one-step RT-PCR in nasal and ocular swabs 7-17 days post infection (p.i.). and in oral swabs 7-15 days p.i. Out of 32 clinical field samples tested, 18 were positive by sandwich ELISA (S-ELISA), while 22 were positive by the one-step RT-PCR.

Animals↗

Autonomously moving nanorods at a viscous interface.

We study the autonomous motion of catalytic nanorods in Gibbs monolayers. The catalytic activity of the rods on a hydrogen peroxide aqueous subphase gives rise to anomalous translational and rotational diffusion. The rods perform a Levy-walk superdiffusive motion that can be decomposed into thermal orientation fluctuations and an active motion of the rods with a constant velocity along their long axis. Since interfacial dissipation increases relative to bulk phase dissipation when miniaturizing the size of objects moving in the interface, the autonomous nanorods allow for precise measurements of surface shear viscosities as low as a few nN s/m. The cross over from active motion toward passive diffusion when increasing the surfactant concentration is explained by a loss of friction asymmetry of the rods.

Journal Article↗

The NF-kappaB pathway blockade by the IKK inhibitor PS1145 can overcome imatinib resistance.

Imatinib represents at present the most attractive therapy for BCR-ABL positive leukemias, even though a percentage of CML patients develop resistance to this compound. For these resistant patients a therapeutic approach based on a combination of drugs is more likely to be effective. In the last years, constitutive NF-kappaB/Rel activity has been demonstrated in several hematological malignancies. As a result, NFkB/Rel-blocking approaches have been proposed as antineoplastic strategies. Furthermore, the identification of specific kinases within the NF-kappaB activation pathway offers a selective target to address tailored therapies. In the current study, we show that the IKK inhibitor PS1145 is able to inhibit the proliferation of CML cell lines and primary BM cells. Moreover, the addition of Imatinib increases the effects of PS1145 in resistant cell lines and BM cells from resistant patients, with a further increase of apoptosis and inhibition of proliferation and colony growth. Our data provide the rational for a new therapeutic approach, which combines Imatinib and the IKK inhibitor PS1145 in CML resistant patients.

Antineoplastic Agents↗

Use of a prophylactic antiemetic with morphine in acute pain: randomised controlled trial.

OBJECTIVE: The aim of this study was to compare the incidence of nausea and vomiting in patients with acute pain treated with morphine along with prophylactic metoclopramide or placebo. METHOD: A randomised controlled trial was carried out on patients requiring morphine for acute pain in the emergency department (ED) setting. Children under the age of 12, patients who had been vomiting or had already received prehospital analgesia, and those unable to give consent were excluded. All patients were given either metoclopramide (10 mg) or placebo (normal saline) followed by intravenous morphine. Pain scores (measured on a visual analogue scale) before and after morphine administration, all incidents of nausea or vomiting, the dose of morphine, and the patients' demographic data were recorded. Fisher's exact test was used for comparing the two groups of patients. RESULTS: A total of 259 patients were recruited. There were 123 patients in the metoclopramide group (age range 15-94 years; median age 53) and 136 patients in the placebo group (age range 17-93 years; median age 52.5). The overall incidence of nausea and vomiting in the whole study population was 2.7%, (1.6% in the metoclopramide group and 3.7% in the placebo group). The difference between the two groups was not statistically significant (Fisher's exact test = 0.451; p = 0.3; z-test statistic = 1.02; 95% CI -6% to 2%). CONCLUSION: When intravenous morphine is administered for acute pain, the overall incidence of nausea and vomiting is low, regardless of whether these patients are given prophylactic metoclopramide or not.

Acute Disease↗

Indometacin as prophylaxis for heterotopic ossification after the operative treatment of fractures of the acetabulum.

Our study was designed to compare the effect of indometacin with that of a placebo in reducing the incidence of heterotopic ossification in a prospective, randomised trial. A total of 121 patients with displaced fractures of the acetabulum treated by operation through a Kocher-Langenbeck approach was randomised to receive either indometacin (75 mg) sustained release, or a placebo once daily for six weeks. The extent of heterotopic ossification was evaluated on plain radiographs three months after operation. Significant ossification of Brooker grade III to IV occurred in nine of 59 patients (15.2%) in the indometacin group and 12 of 62 (19.4%) receiving the placebo. We were unable to demonstrate a statistically significant reduction in the incidence of severe heterotopic ossification with the use of indometacin when compared with a placebo (p = 0.722). Based on these results we cannot recommend the routine use of indometacin for prophylaxis against heterotopic ossification after isolated fractures of the acetabulum.

Acetabulum↗

Deleterious functional impact of anemia on young adolescent school girls.

UNLABELLED: Iron deficiency anemia during adolescence may reduce physical work capacity and cognitive function. OBJECTIVES: To assess the physical work capacity and cognition of underprivileged anemic schoolgirls in Vadodara in early adolescence as compared to their non-anemic counterparts. DESIGN: Prior to initiating anemia control interventions, schoolgirls in early adolescence were studied with regard to their hemoglobin status, physical work capacity and cognitive functions. SETTING: Schoolgirls from four municipal primary schools in the age of 9 - 14 years were studied. METHODS: In four Primary Municipal schools, hemoglobin of subjects was assessed using standard methods; physical work capacity using Modified Harvards Step test and cognitive functions using selected tests from the modified Wechsler Intelligence Scale for Children (WISC), suitably adapted for this group (n = 230). RESULTS: The mean hemoglobin was 11.32 g/dL, and anemia prevalence: 67%. A higher number of steps were climbed and a shorter time was taken to revert to the basal pulse rate (recovery time) by non-anemic girls compared to anemic girls (P < 0.001). Significantly lower scores in digit span and visual memory test were seen in anemic compared to non-anemic girls. The adverse impact of anemia remained after controlling for undernutrition (BMI). CONCLUSION: Anemia is likely to adversely affect physical work capacity and cognition in young adolescent girls undergoing pubertal development. Further research should be conducted in both school and community based settings to cover non-school going children.

Adolescent↗

Induction of cytotoxic T-lymphocytes by electroporation-enhanced needle-free skin immunization.

A needle-free method based on transcutaneous electroporation is described for delivering peptide vaccines. The K(b)-binding OVA-peptide SIINFEKL was used as an example to induce the peptide-specific cytotoxic T-lymphocytes (CTL) response in mice. A saturated anionic lipid was added during electroporation, and post-pulse electro-osmosis was applied to enhance the vaccine delivery. Electroporation was found to stimulate the exodus of Langerhans cells (LC) from the skin. The peptide transported into and through murine skin was measured using a Franz diffusion apparatus. Most peptide was retained in the skin rather than passing through the skin in the process. The peptide was delivered to the dorsal skin of mice by in vivo electroporation. An electroporation-transportable oligonucleotide with CpG motif was used as adjuvant. The efficacy of peptide delivery was comparable to that of intradermally injected with Freund's complete adjuvant (FCA). Peptide-specific CTL response to the vaccine delivered by needle-free electroporation/electro-osmosis was equivalent to that delivered by intradermal injection, as determined by production of the peptide-specific IFN-gamma in ELISPOT assay.

Adjuvants, Immunologic↗

Cortical neuronal densities and lamination in focal cortical dysplasia.

Focal cortical dysplasia (FCD) is considered to represent a malformation due to abnormal cortical development (MCD) and is an important cause of focal epilepsy. The histopathological features include abnormal laminar architecture, the presence of hypertrophic and dysmorphic neurones in FCD type IIA and additional balloon cells in FCD type IIB. The events causing these sporadic lesions are unknown, but abnormal progenitor cell proliferation occurring late in corticogenesis has been proposed. FCD-like lesions have, however, also been described following a cerebral injury early in life. We carried out a stereological assessment on 15 cases of FCD on NeuN- and Nissl-stained sections from patients with a wide age range, and identified a significant reduction in the neuronal density in all cases in the region of dysplasia compared to the adjacent unaffected cortex (mean neuronal densities 19.2x10(3)/mm3 in the region of dysplasia; 42.8x10(3)/mm3 in the adjacent cortex). Relative differences in neuronal density and size in FCD cases between the superficial (layer I and II) and deep cortical laminae (layer V and VI) were similar to that observed in other pathologies including mild MCD, temporal neocortex adjacent to hippocampal sclerosis as well as in a non-epilepsy surgical control group. The lower overall neuronal densities observed in FCD may reflect neuropil expansion, a local failure of neuronal migration, proliferation or secondary neuronal loss. The preservation of relative differences in neuronal densities between cortical layers and laminar patterns of neurofilament staining in FCD would support the view that the temporal sequence of lamination is not affected.

Adolescent↗

Comparative sequence analysis of the large polymerase protein (L) gene of peste-des-petits ruminants (PPR) vaccine virus of Indian origin.

The complete nucleotide sequence of the large polymerase (L) protein of the peste-des-petits ruminants (PPR) vaccine virus (PPRV Sungri/96) belonging to the Asian lineage was determined. The gene was 6643 nucleotides in length from the gene-start to the gene-end and encoded a polypeptide of 2183 amino acids. The PPRV Sungri/96 has a nucleotide homology of 94.1% for PPRV Nigeria 75/1 to 64.4% for Canine distemper virus. At amino acid level PPRV Sungri/96 has an amino acid identity of 96.2% with PPRV Nigeria 75/1 and 70.4% to 74.8% with other morbilliviruses. All the established domains in L protein characteristic of paramyxoviruses were also found to be present in PPRV Sungri/96. Phylogenetic analysis of different L proteins of morbilliviruses revealed five well-defined clusters as observed previously. The 3' trailer sequence of PPRV Sungri/96 is of 37 nucleotides long which is very similar to that of other morbilliviruses. To the best of our knowledge this is the first report describing the polymerase gene sequence of PPRV Indian isolate.

3' Untranslated Regions↗

Pilot study of topical delivery of methotrexate by electroporation.

BACKGROUND: The topical administration of methotrexate (MTX) for the treatment of psoriasis and neoplastic diseases is restricted by the poor diffusion of MTX across the stratum corneum. OBJECTIVES: We applied electroporation to increase the transdermal transport of MTX. METHODS: Electrodes were placed either side-by-side on the surface of excised full thickness pig skin, or on a piece of skin clamped between compartments of a vertical diffusion chamber. Sixty rectangular electric pulses at 120 V, 1 ms and 1 Hz were applied across the skin. MTX was left on the skin surface for an additional 10 min to take advantage of diffusion through electropores. Cumulative drug transport was measured by radioactive tracing, using [3H]-methotrexate, from punch biopsy samples taken from under the cathode. The integrity of the radioisotope was verified by high-performance liquid chromatography. RESULTS: Using side-by-side electrodes, treatment with the pulses alone resulted in a 2.5-fold increase; adding anionic lipid enhancers to the pulses resulted in a 4.4-fold enhancement compared with passive diffusion. Concurrent iontophoresis for the 11-min time period made a nonsignificant contribution. To reduce tissue resistance we used 40 degrees C hyperthermia in a vertical diffusion chamber; transport was increased 11-fold to 53 microg cm(-2) (flux = 290 microg cm(-2) h(-1)). MTX penetration profiles indicated that more than half of the MTX was confined to the epidermis and papillary dermis. The tissue concentration in this superficial reactive unit was 1.7 mmol L(-1). CONCLUSIONS: Electroporation of MTX with an anion lipid enhancer under a mild hyperthermic environment provided a significant transdermal delivery within a short application time. The method may be an effective means of drug delivery for treating psoriasis or other MTX-sensitive disorders and avoids the potential systemic toxicity.

Administration, Cutaneous↗

Usefulness of the direct agglutination test in the early detection of subclinical Leishmania donovani infection: a community-based study.

The value of a direct agglutination test (DAT) in the detection of subclinical infections with Leishmania donovani has recently been investigated in the Indian state of Bihar, after the sensitivity and specificity of the test had been determined. When used to screen sera from 108 parasitologically confirmed cases of visceral leishmaniasis, 50 patients with active, non-leishmanial infection, and 641 healthy controls living close to, or distant from, an endemic area, the test was found to be 91.7% sensitive and 100% specific if a titre of 1:800 was used as the threshold for seropositivity. During a longitudinal clinical study in a rural, VL-endemic area of the Indian state of Bihar, the test was used, with 1:800 set as the threshold titre, to determine the baseline prevalence of infection with L. donovani among villagers who, though showing no symptoms of VL, had recently been febrile for at least 2 weeks. The 234 subjects of this study were either VL-case contacts [i.e. members of households in which there were active or cured VL cases (N=78)] or the members of control households with no cases or history of the disease (N=156). The results of DAT at the start of the study indicated that 49 (20.9%) of the subjects--29 (37.2%) of the VL-case contacts and 20 (12.8%) of the other subjects--were seropositive and therefore probably had subclinical infections with L. donovani. During the subsequent 9 months of follow-up, however, only eight of the subjects found seropositive at the start of the study--seven (24.1%) of the seropositive case contacts but only one (5.0%) of the other seropositives--developed symptomatic VL, all by month 6 of the follow-up. Compared with their neighbours, therefore, individuals who shared households with active or cured cases of VL appeared at greater risk not only of L. donovani infection (indicating focal transmission) but also of developing symptomatic disease once infected. Curiously, among the seropositive case contacts, those from the households that harboured active cases of VL at the baseline survey were less likely to develop symptomatic VL during the 9 months of follow-up than those from households that harboured only cured cases (18.8% v. 30.8%). The wide-spread use of DAT could allow the detection and early treatment of latent L. donovani infections and so contribute to the elimination of VL, at least as a public-health problem, from India.

Agglutination Tests↗

Biochemical characterization and distribution of glutathione S-transferases in leaping mullet (Liza saliens).

In this study, feral leaping mullet (Liza saliens) liver cytosolic glutathione S-transferases (GSTs) were investigated and characterized using 1-chloro-2,4-dinitrobenzene (CDNB) and ethacrynic acid (EA) as substrates. The average GST activities towards CDNB and EA were found to be 1365 +/- 41 and 140 +/- 20 nmol/min per mg protein, respectively. The effects of cytosolic protein amount and temperature ranging from 4 to 70 degrees C on enzyme activities were examined. While both activities towards CDNB and EA showed similar dependence on protein amount, temperature optima were found as 37 and 42 degrees C, respectively. In addition, the effects of pH on GST-CDNB and -EA activities were studied and different pH activity profiles were observed. For both substrates, GST activities were found to obey Michaelis-Menten kinetics with apparent V(max) and K(m) values of 1661 nmol/min per mg protein and 0.24 mM and 157 nmol/min per mg protein and 0.056 mM for CDNB and EA, respectively. Distribution of GST in Liza saliens tissues was investigated and compared with other fish species. Very high GST activities were measured in tissues from Liza saliens such as liver, kidney, testis, proximal intestine, and gills. Moreover, our results suggested that GST activities from Liza saliens would be a valuable biomarker for aquatic pollution.

Animals↗

Yield of human adipose-derived adult stem cells from liposuction aspirates.

BACKGROUND: Primary cultures of isolated human adipose-derived adult stem (ADAS) cells are multipotent and differentiate in vitro along the adipocyte, chondrocyte, neuronal, osteoblast, and skeletal muscle pathways. METHODS: We examined the ADAS cell yield per unit volume of liposuction tissue, and their surface protein phenotype by flow cytometry. Adipogenesis was assessed by Oil Red O staining and ELISA analysis of leptin secretion. RESULTS: The donor population was 87.5% female (n=18) with a mean age (+/-SD) of 44+/-10 years and body mass index (BMI) of 24.9+/-2.7. The mean cell yield was 404 000+/-206 000 cells per milliliter of lipoaspirate (n=18). Linear regression analysis of the cells derived from the female donors demonstrated a significant negative correlation between the number of cells obtained per milliliter of lipoaspirate with the BMI but not the age of the donor. The undifferentiated ADAS cells were homogeneously positive for the cell-surface markers CD10, CD13, CD29, CD44, CD49e, CD59, CD90, and HLA-ABC, and homogeneously negative for the cell surface markers CD11b, CD45, and HLA-DR. The absence of the panhematopoietic marker, CD45, indicates that the ADAS cells do not derive from circulating BM hematopoietic stem cells. Adipocyte differentiation led to a 5.1-fold increase in Oil Red O staining, and a 196-fold increase in leptin secretion levels. Culture of the cells in the presence of antibiotic and fungizone did not alter the undifferentiated ADAS cell immunophenotype based on flow cytometry, or their adipocyte differentiation based on leptin secretion. DISCUSSION: The ability to isolate a consistently homogeneous population of undifferentiated adult stem cells from adipose tissue of multiple donors supports their potential utility in future tissue-engineering applications.

Adipose Tissue↗

Development of a N gene-based PCR-ELISA for detection of Peste-des-petits-ruminants virus in clinical samples.

A highly sensitive N gene-based PCR-ELISA for the detection of Peste-des-petits-ruminants virus (PPRV) was developed. The RT-PCR yielded a digoxigenin (DIG)-labeled product of 336 bp comprising a sequence from PPRV N gene, which was then detected by ELISA. The assay could detect the viral RNA in PPRV-infected tissue culture fluids with a titer as low as 0.1 TCID(50)/ml. The assay is 10,000 times more sensitive than a classical RT-PCR combined with agarose gel electrophoresis. The assay could detect the virus in the clinical samples, which were negative by conventional sandwich ELISA (S-ELISA). The percentage positivity of the assay in detecting the virus in clinical samples was 66.2% compared to 48.6% for S-ELISA. The assay was more sensitive than S-ELISA also in detecting the virus in early as well as late phases of the disease. In addition, the assay could also be used for differential diagnosis of PPRV and Rinderpest virus (RPV).

Animals↗

Large-scale expansion of mammalian neural stem cells: a review.

A relatively new approach to the treatment of neurodegenerative diseases is the direct use of neural stem cells (NSCs) as therapeutic agents. The expected demand for treatment from the millions of afflicted individuals, coupled with the expected demand from biotechnology companies creating therapies, has fuelled the need to develop large-scale culture methods for these cells. The rapid pace of discovery in this area has been assisted through the use of animal model systems, enabling many experiments to be performed quickly and effectively. This review focuses on recent developments in expanding human and murine NSCs on a large scale, including the development of new serum-free media and bioreactor protocols. In particular, engineering studies that characterise important scale-up parameters are examined, including studies examining the effects of long-term culture of NSCs in suspension bioreactors. In addition, recent advances in the human NSC system are reviewed, including techniques for the evaluation of NSC characteristics.

Animals↗