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P Kumar

Publications and source records attributed to P Kumar.

At least 55 records · Page 3Linked to original sources
PubMed2005

Histology, immunohistochemistry and ultrastructure of the equine palatine tonsil.

The palatine tonsils of five young horses formed 10-12 cm elongated follicular structures extending from the root of the tongue on either side to the base of the epiglottis and lateral to the glossoepiglottic fold. The stratified squamous non-keratinized epithelium of the outer surface was modified into crypts as reticular epithelium by heavy infiltration of lymphoid cells from underlying lymphoid follicles. In places, lymphoid tissue reaching almost to the surface and with only one to two cell layers intact was identified as the lymphoepithelium. Langerhans cells with Birbeck granules were interspersed between epithelial cells. Lymphoid tissue organized in lymphoid follicles constituted the parenchyma of the palatine tonsil. CD4-positive cells were more numerous and CD8-positive lymphocytes less numerous compared with their distribution in the lingual tonsil. B cells and macrophages were also more numerous than in the lingual tonsil and lectins showed a different pattern of attachment. M cells were not observed. High endothelial venules with well-developed vesiculo-vacuolar organelle had structural evidence of transendothelial and interendothelial migration of lymphocytes. Striated muscles as seen in the deeper lamina propria mucosae of the lingual tonsil were absent. The immunohistological and ultrastructural characteristics of the equine palatine tonsil are similar to those of humans but differ from those of the lingual tonsil and are consistent with a role as an effector and inductor immunological organ.

Animals↗
PubMed2005

Tuberculous meningitis in BCG vaccinated and unvaccinated children.

BACKGROUND: A modified clinical presentation of tuberculous meningitis (TBM) in children vaccinated with BCG has been described in the literature. However, most reports are old and not based on actual comparisons and tests of significance. Also, neuroimaging features were not compared. With large scale BCG coverage, it becomes pertinent to describe the "modified" presentation and identify any significant differences between vaccinated and unvaccinated children with TBM. METHODS: A total of 150 consecutive hospitalised children (96 unvaccinated, 54 vaccinated) were enrolled. They all satisfied predefined criteria for diagnosis of TBM. Clinical and radiological features of children with/without a BCG scar were compared. RESULTS: Univariate analysis revealed that the vaccinated children with TBM had significantly lower rates of altered sensorium (68.5% v 85.4% unvaccinated; OR 2.2 (1.1 to 6.2); p = 0.019) and focal neurological deficits (20.3% v 39.5% unvaccinated; OR 2.6 (1.1 to 6.0); p = 0.016), and higher mean (SD) Glasgow Coma Scale score (10.2 (3.4) v 8.76 (2.7) unvaccinated; p = 0.010) and cerebrospinal fluid cell count (210.9 v 140.9 unvaccinated; p = 0.019). No significant radiological differences were seen. Short term outcome was significantly better in the vaccinated group with 70% of the total severe sequelae and 75% of the total deaths occurring in the unvaccinated group (p = 0.018). CONCLUSION: Children with TBM who have been vaccinated with BCG appear to maintain better mentation and have a superior outcome. This may in part be explained by the better immune response to infection, as reflected in the higher CSF cell counts in this group in the present study.

Antitubercular Agents↗
PubMed2005

Intranasal immunization using biphasic lipid vesicles as delivery systems for OmlA bacterial protein antigen and CpG oligonucleotides adjuvant in a mouse model.

The nasal mucosa is an important arm of the mucosal system since it is often the first point of contact for inhaled antigens. The ineffectiveness of the simple delivery of soluble antigens to mucosal membranes for immunization has stimulated extensive studies in appropriate delivery systems and adjuvants. We have evaluated biphasic lipid vesicles as a novel intranasal (i.n.) delivery system (designated as vaccine targeting adjuvant, VTA) containing bacterial antigens and CpG oligodeoxynucleotides (ODNs). Results show that administration of antigen and CpG ODNs in biphasic lipid vesicles resulted in greater induction of IgA levels in serum (P< 0.05) and mucosal antibody responses such as IgA in nasal secretions and lung (P< 0.01) after immunization with a combined subcutaneous (s.c.)/i.n. as compared to s.c./s.c. approach. Based on antibody responses, VTA formulations were found to be suitable as delivery systems for antigens and CpG ODNs by the intranasal route, resulting in a Th2-type of immune response, characterized by IgG1 and IL-4 production at the systemic level.

Adjuvants, Immunologic↗
PubMed2005

Caudal additives in pediatrics: a comparison among midazolam, ketamine, and neostigmine coadministered with bupivacaine.

Single-shot "kiddie caudal" with bupivacaine alone is losing popularity because of its duration of 4-8 h. In a prospective randomized double-blind clinical study, we assessed and compared the efficacy of ketamine, midazolam, and neostigmine coadministered with bupivacaine in a caudal epidural to provide intraoperative and postoperative pain relief. Eighty children (ASA status I) aged 5-10 yr undergoing unilateral inguinal herniotomy were allocated randomly in equal numbers (n = 20) into 4 groups to receive a caudal injection of 0.25% bupivacaine (1 mL/kg) with or without ketamine (0.5 mg/kg), midazolam (50 microg/kg), and neostig-mine (2 microg/kg), after the induction of standardized general anesthesia without premedication. Monitoring for pain, sedation, postoperative nausea/vomiting, dizziness, and pruritus was performed by anesthesiologists blinded to the study allocation. The time to first analgesic administration (paracetamol syrup) was longer (P < 0.05) in the bupivacaine-neostigmine group and the bupivacaine-midazolam group than in the other groups. Undesirable effects, such as emesis, pruritus, and dizziness, were comparable in all groups. However, the incidence of hallucination was more frequent in the bupivacaine-ketamine group compared with the other groups. This study shows that single-shot caudal coadministration of bupivacaine-neostigmine and bupivacaine-midazolam was associated with an extended duration of postoperative pain relief.

Anesthesia Recovery Period↗
PubMed2005

The prevalence of pressure ulcers in hospitalised patients in a university hospital in India.

OBJECTIVE: To estimate the prevalence of pressure ulcers in hospitalised patients and any underlying or predisposing factors to ulceration. METHOD: This cross-sectional study took place in a university hospital in Varanasi, India. A total of 445 patients hospitalised in medical and surgical wards were examined in a single day for the number, site and grade of pressure ulcers. Haemoglobin, serum albumin and blood sugar levels of patients with pressure ulcers were recorded. RESULTS: The prevalence of pressure ulcers was high (4.94%). Anaemia, malnutrition and diabetes were important risk factors, while morbidity due to pressure ulcers in long-stay wards, such as neurology, was exceptionally high (40.9%). CONCLUSION: Pressure ulcers remain one of the most neglected aspects of health-care provision in India and identifying their associated risk factors at an early stage may go a long way in preventing their occurrence.

Adult↗
PubMed2005

The cooperative transforming effects of PAX3-FKHR and IGF-II on mouse myoblasts.

Alveolar rhabdomyosarcoma (ARMS) cells express high levels of PAX3-FKHR and IGF-II. In this study, we have investigated the effects of PAX3-FKHR and IGF-II on the expression of muscle regulatory factors (myf5, MyoD and myogenin), and platelet derived growth factor-B (PDGF-B) and vascular endothelial growth factor (VEGF) in mouse C2C12 myoblasts in vitro. PAX3-FKHR induced cell cycling of C2C12 cells and promoted proliferation whilst blocking myogenesis. IGF-II inhibited their differentiation without influencing proliferation. Western blotting showed that PAX3-FKHR and IGF-II blocked the expression of myogenin and MyoD respectively. Since MyoD affects early myogenesis and myogenin controls terminal differentiation, a combination of PAX3-FKHR and IGF-II synergistically blocks myogenesis at several different stages in differentiation. We have also shown that the major survival and angiogenic cytokines, PDGF-B and VEGF, were induced by IGF-II and PAX3-FKHR respectively. A combination of PAX3-FKHR and IGF-II could synergistically up regulate the expression of PDGF-B and VEGF and stabilize their high expression levels. Our results suggest that high expression of PAX3-FKHR and IGF-II in ARMS synergistically play a key role in oncogenesis and tumour progression of ARMS.

Animals↗
PubMed2005

Average annual risk of tuberculous infection in India.

Estimates of the prevalence of tuberculous infection among children 1-9 years of age were available for four defined zones of India from a recently concluded tuberculin survey. These were pooled together and the average annual risk of infection in the country was computed as 1.5%. It was higher in urban areas, at 2.2%, than in rural areas, at 1.3%. The results call for further intensification of tuberculosis control activities, especially in urban areas, greater involvement of private practitioners and information, education and communication (IEC) for high-risk groups, to reduce the diagnostic and treatment delay thereby reducing the transmission of infection in all settings.

Child↗
PubMed2005

Annual risk of tuberculous infection in four defined zones of India: a comparative picture.

SETTING: Twenty-six selected districts in India. OBJECTIVES: To estimate the average annual risk of tuberculous infection (ARTI) in four defined zones in the country. STUDY DESIGN: A tuberculin survey was conducted in selected clusters of 26 districts in four defined zones of India. Children 1-9 years of age were subjected to tuberculin testing with ITU PPD RT23 with Tween 80, and the maximum transverse diameter of induration was measured 72 h later. Prevalence of infection was estimated using the cut-off point method (Method I) and the mirror-image technique (Method II) among children without bacille Calmette-Guérin scar. Results from individual zones have been reported earlier, and the results from all four zones are presented here as a consolidated summary. RESULTS: The ARTI computed from estimated prevalence was found to be lowest in the southern zone (Method I: 1.1%, Method II: 1.0%). It was higher in the eastern zone (1.3% by both methods) and highest in the western (Method I: 1.8%, Method II: 1.6%) and northern zones (1.9% by both methods). The proportion of infected children was found to be significantly higher in urban than in rural areas in all zones. CONCLUSION: The intensified tuberculosis control efforts need to be sustained for many years.

Child↗
PubMed2005

Spectrum and antibiotic susceptibility pattern of bacterial isolates from conjunctival swabs.

Conjunctivitis is the most common disease of conjunctiva which occurs by exogenous or endogenous source. Bacterial conjunctivitis is the most common type of this infection for which emperical treatment is started without knowing the etiological agents because prior cultures are generally not taken. We conducted this survey to study the etiological agents of conjunctivitis in a total of 6763 swabs obtained over a period of four years (2001 to 2004). The prevalence of bacterial conjunctivitis was found to be 20.4% with a predominance of Staphylococcus aureus (87.2%) followed by Streptococcus pneumoniae (4.7%) and gram negative rods (E.coli + Klebsiella spp. + Pseudomonas spp.) in 8.1% swabs. For S. aureus, amikacin showed maximum sensitivity (73.2%) while for S. pneumoniae, cefotaxime (90.6%) and cefazolin (89%) were found to be highly sensitive drugs. For gram negative rods, ceftazidime (74.1%) and cefotaxime (67%) were found to be preferred options. Thus it is concluded that bacterial conjunctivitis in our hospital is predominated by S. aureus. The bacterial isolates obtained from conjunctiva have not yet attained a high level of antibiotic resistance and hence averts the need to unnecessarily start new/latest generations of antibiotic eyedrops or antibiotic combination which may lead to acquisition of resistance by these bacteria.

Bacteria↗
PubMed2004

Construction of oligonucleotide arrays on a glass surface using a heterobifunctional reagent, N-(2-trifluoroethanesulfonatoethyl)-N-(methyl)-triethoxysilylpropyl-3-amine (NTMTA).

A rapid method for construction of oligonucleotide arrays on a glass surface, using a novel heterobifunctional reagent, N-(2-trifluoroethanesulfonatoethyl)-N-(methyl)-triethoxysilylpropyl-3-amine (NTMTA), has been described. The heterobifunctional reagent, NTMTA, carries two different thermoreactive groups. The triethoxysilyl group on one end is specific towards silanol functions on the virgin glass surface, while the trifluoroethanesulfonyl (tresyl) group on the other end of the reagent reacts specifically with aminoalkyl- or mercaptoalkyl- functionalized oligonucleotides. Immobilization of oligonucleotides on a glass surface has been realized via two routes. In the first one (A), 5'- aminoalkyl- or mercaptoalkyl-functionalized oligonucleotides were allowed to react with NTMTA to form a oligonucleotide-triethoxysilyl conjugate which, in a subsequent reaction with unmodified (virgin) glass microslide, results in surface-bound oligonucleotides. In the second route (B), the NTMTA reagent reacts first with a glass microslide whereby it generates trifluoroethanesulfonate ester functions on it, which in a subsequent step react with 5'-aminoalkyl or mercaptoalkyl oligonucleotides to generate support-bound oligonucleotides. Subsequently, the oligonucleotide arrays prepared by both routes were analyzed by hybridization experiments with complementary oligonucleotides. The constructed microarrays were successfully used in single and multiple nucleotide mismatch detection by hybridizing these with fluorescein-labeled complementary oligonucleotides. Further more, the proposed method was compared with the existing methods with respect to immobilization efficiency of oligonucleotides.

Base Pair Mismatch↗
PubMed2004

A new heterobifunctional reagent for immobilization of biomolecules on glass surface.

Synthesis of a new heterobifunctional reagent, [N-(2-trifluoroethanesulfonatoethyl)-N-(methyl)-triethoxysilylpropyl-3-amine] (NTMTA) is described for the immobilization of a variety of biomolecules on glass surface. Its triethoxysilyl group reacts with glass surface and trifluoroethanesulfonate ester structure reacts selectively with aminoalkyl/mercaptoalkyl function in biomolecules. The immobilization can be achieved by two ways involving two steps. The first route involves the reaction of NTMTA with glass beads followed by attachment of aminoalkyl- or mercaptoalkylated biomolecules. The second one involves the reaction of biomolecules, viz., oligonucleotides, proteins, etc., with NTMTA via their aminoalkyl or mercaptoalkyl functions to form a biomolecule conjugate, which is then reacted with glass beads (unmodified) to complete immobilization process. This has been demonstrated by successful immobilization of 5'-mercaptoalkyl- or aminoalkylated oligonucleotides and some commonly used enzymes on glass beads using NTMTA reagent.

Glass↗
PubMed2004

Indirect sensing of insulin-induced hypoglycaemia by the carotid body in the rat.

The most physiologically important sensors for systemic glucoregulation are located in extra-cranial sites. Recent evidence suggests that the carotid body may be one such site. We assessed rat carotid body afferent neural output in response to lowered glucose, indirectly by measurement of ventilation, and directly by recording single or few-fibre chemoafferent discharge, in vitro. Insulin (0.4 Ukg(-1)min(-1))-induced hypoglycaemia (blood glucose reduced by ca 50% to 3.4 +/- 0.1 mmoll(-1)) significantly increased spontaneous ventilation in sham-operated animals but not in bilateral carotid sinus nerve sectioned (CSNX) animals. In both groups, metabolic rate (measured as ) was almost doubled during hypoglycaemia. The ventilatory equivalent was unchanged in the sham group leading to a maintained control level of P(a, CO(2)), but was significantly reduced in the CSNX group, giving rise to an elevation of 6.0 +/- 1.3 mmHg in P(a, CO(2)). When pulmonary ventilation in sham animals was controlled and maintained, phrenic neural activity increased during hypoglycaemia and was associated with a significant increase in P(a, CO(2)) of 5.1 +/- 0.5 mmHg. Baseline chemoreceptor discharge frequency, recorded in vitro, was not affected, and did not increase when the superfusate [glucose] was lowered from 10 mm to 2 mm by substitution with sucrose: 0.40 +/- 0.20 Hz to 0.27 +/- 0.15 Hz, respectively (P > 0.20). We suggest therefore that any potential role of the carotid bodies in glucose homeostasis in vivo is mediated through its transduction of some other metabolically derived blood-borne factor rather than glucose per se and that this may also provide the link between exercise, metabolic rate and ventilation.

Acidosis, Respiratory↗
PubMed2004

Tuberculin sensitivity among children vaccinated with BCG under universal immunization programme.

A tuberculin survey was conducted among 45988 children with BCG scar and 54227 children without BCG scar between 1-9 years of age and residing in selected rural areas of three defined zones of India. About 45-60% of the BCG-vaccinated children elicited reactions < 5 mm in size and about 70-80% had reactions < 10 mm. Therefore, in the majority of children (showing tuberculin reaction of < 10 mm), BCG-induced tuberculin sensitivity does not interfere with interpretation of tuberculin test. The study also revealed that a proportion of reactions among BCG vaccinated children in 5-9 mm, 10-14 mm and 15-19 mm range may be attributable to BCG vaccination. Therefore, reactions between 10-14 mm and especially 15-19 mm among the vaccinated children must be interpreted carefully. However, 19 mm was observed as the upper limit for BCG induced tuberculin sensitivity and all reactions >- 20 mm in size may be considered to be due to infection with tubercle bacilli, irrespective of the BCG vaccination status.

BCG Vaccine↗
PubMed2004

Protective effect of BCG among children vaccinated under universal immunization programme.

A case-control study was conducted to estimate the protective effect of BCG vaccination against tuberculosis among children. The children with suspicion of tuberculosis (TB) attending two hospitals in Bangalore city were registered into the study and subjected to detailed clinical examination and investigations. The presence of BCG scar was taken as evidence of vaccination. Modified Stegen-Jones scoring method was adopted for diagnosing TB. The hospital children with score of 7 were considered as TB cases. Children residing in the neighbourhood of cases were similarly investigated and those scoring 4 were labeled as controls. A total of 118 age-sex matched case-control pairs were identified and final analysis was confined to 113 cases and 109 controls after excluding children with doubtful BCG scar. A low protective effect of BCG vaccination at 31% (not significant, statistically) was observed against TB - all forms combined, among children vaccinated as under Universal Immunization Programme. Though the protective efficacy against extra-pulmonary TB was observed to be higher than for pulmonary TB, it was also not significant, statistically. It will be appropriate to conduct further studies on protection rendered by BCG vaccination against tuberculous meningitis and other severe forms of TB. Besides, the quality of vaccination programme including cold chain maintenance also needs to be evaluated.

Adolescent↗