Magnetic properties of planar nanowire arrays of Co fabricated on oxidized step-bunched silicon templates.

Planar nanowire (NW) arrays of Co grown on oxidized step-bunched Si(111) templates exhibit room temperature ferromagnetic behaviour for wire widths down to 25 nm. Temperature and thickness dependent magnetization studies on these polycrystalline NW arrays show that the magnetic anisotropy of the NW array is dominated by shape anisotropy, which keeps the magnetization in-plane with easy axis parallel to the wires. This shape related uniaxial anisotropy is preserved even at low temperatures (10 K). Thickness dependent studies reveal that the magnetization reversal is governed by the curling mode reversal for thick wires whereas thinner wires exhibit a more complex behaviour which is related to thermal effects and size distribution of the crystal grains that constitute the NWs.

Prevalence of multidrug-resistant tuberculosis among newly diagnosed cases of sputum-positive pulmonary tuberculosis.

BACKGROUND & OBJECTIVES: The prevalence of multidrug-resistant tuberculosis (MDR-TB) is increasing throughout the world. Although previous treatment for TB is the most important risk factor for development of MDR-TB, treatment-naοve patients are also at risk due to either spontaneous mutations or transmission of drug-resistant strains. We sought to ascertain the prevalence of MDR-TB among new cases of sputum-positive pulmonary TB. METHODS: This was a prospective, observational study involving newly diagnosed cases of sputum-positive pulmonary tuberculosis diagnosed between 2008 and 2009 carried out in New Delhi, India. All sputum-positive TB cases were subjected to mycobacterial culture and first-line drug-susceptibility testing (DST). MDR-TB was defined as TB caused by bacilli showing resistance to at least isoniazid and rifampicin. RESULTS: A total of 218 cases of sputum-positive pulmonary tuberculosis were enrolled between 2008 and 2009. Of these, 41 cases had negative mycobacterial cultures and DST was carried out in 177 cases. The mean age of the patients was 27.8 ± 10.2 yr; 59 patients (27%) were female. All patients tested negative for HIV infection. Out of 177 cases, two cases of MDR-TB were detected. Thus, the prevalence of MDR-TB among newly diagnosed pulmonary tuberculosis patients was 1.1 per cent. INTERPRETATION & CONCLUSIONS: MDR-TB prevalence is low among new cases of sputum-positive pulmonary TB treated at primary care level in Delhi. Nation-wide and State-wide representative data on prevalence of MDR-TB are lacking. Efforts should be directed towards continued surveillance for MDR-TB among newly diagnosed TB cases.

Prevalence of multidrug-resistant tuberculosis among category II pulmonary tuberculosis patients.

BACKGROUND & OBJECTIVES: Multidrug-resistant tuberculosis (MDR-TB) has emerged as a significant global health concern. The most important risk factor for the development of MDR-TB is previous anti-tuberculosis therapy. Category II pulmonary TB includes those patients who had failed previous TB treatment, relapsed after treatment, or defaulted during previous treatment. We carried out this study to ascertain the prevalence of MDR-TB among category II pulmonary TB patients. METHODS: This was a cross-sectional, descriptive study involving category II pulmonary TB patients diagnosed between 2005 and 2008. All sputum-positive category II TB cases were subjected to mycobacterial culture and drug-susceptibility testing (DST). MDR-TB was defined as TB caused by bacilli showing resistance to at least isoniazid and rifampicin. RESULTS: A total of 196 cases of sputum-positive category II pulmonary tuberculosis patients were included. Of these, 40 patients (20.4%) had MDR-TB. The mean age of MDR-TB patients was 33.25 ± 12.04 yr; 9 patients (22.5%) were female. Thirty six patients showed resistance to rifampicin and isoniazid; while 4 patients showed resistance to rifampicin, isoniazid and streptomycin. The prevalence of MDR-TB among category-II pulmonary tuberculosis patients was 20.4 per cent. INTERPRETATION & CONCLUSIONS: The prevalence of MDR-TB in category II TB patients was significant. However, nation-wide and State-wide representative data on prevalence of MDR-TB are lacking. We stress the importance of continuous monitoring of drug resistance trends, in order to assess the efficacy of current interventions and their impact on the TB epidemic.

Meconium peritonitis presenting as abdominal calcification: three cases with different pathology.

Intra-abdominal calcification is uncommon in newborns and has several causes of which meconium peritonitis is the most frequent. Three neonates with intra-abdominal calcification as a complication of meconium peritonitis are presented. The types of meconium peritonitis were cystic, meconium pseudocyst and meconium ascites. Two required surgical intervention. Meconium peritonitis should be considered in newborns with intra-abdominal calcification.

Histoplasmosis: cytodiagnosis and review of literature with special emphasis on differential diagnosis on cytomorphology.

BACKGROUND: Human infection with Histoplasma capsulatum runs the gamut from asymptomatic to disseminated disease. In immunocompromised patients, a tiny inoculum can lead to widespread disseminated infection. Early diagnosis and initiation of treatment is therefore important. OBJECTIVE: To review the cases of histoplasmosis diagnosed on fine needle aspiration cytology (FNAC) and to discuss the clinical presentation, associated inflammatory response, load of organisms and differential diagnosis on cytomorphology in these cases. METHODS: Retrospective review of seven cases of histoplasmosis at a tertiary-care centre during the period from 1998 to 2009 was performed. Clinical presentation along with cytomorphological features were studied and discussed in detail. RESULTS: The mean age of patients was 48.6 years and six out of seven were male. History of immunodeficiency (HIV) was available in five cases. Six patients presented with peripheral and/or abdominal lymphadenopathy. One patient had nodular shadows in both lungs and two also had skin lesions. On cytological smears, a variable load of uniform round to oval, about 2-4 microm in diameter, budding yeasts were seen intracellularly (within histiocytes) as well as extracellularly. In one case (HIV positive), these organisms were also seen within neutrophil polymorphonuclear leucocytes. In two cases, an inflammatory response in the form of epithelioid cell granulomas along with multinucleated giant cells was seen. CONCLUSIONS: FNAC is a reliable tool to recognize infection with H. capsulatum in tissues. This infection can cause a variable inflammatory response, which should be considered while reporting on such cases.

Severe thrombocytopenia secondary to tubercular lymphadenitis.

A 5-year-old girl presented with a left axillary lymph node mass associated with generalised petechiae and mucosal bleeding and was diagnosed as tubercular lymphadenitis associated with immune thrombocytopenia. She responded well to anti-tubercular therapy. Tuberculosis should be considered in the differential diagnosis of lymphadenopathy and thrombocytopenia.

Giant intramuscular calcifying aponeurotic fibroma of gluteus maximus: case report.

Calcifying aponeurotic fibroma (CAF) is a rare soft tissue tumour which occurs mainly in children and adolescents. It usually involves the distal portion of the extremities, i.e. the hands and feet. A 2-year-old child with a large CAF is presented. The case was unusual in view of its large size (10 × 7 × 5 cm), dense calcification in such a young child, and because it was situated in the substance of gluteus maximus muscle. There has been no recurrence at 3-year follow-up.

Receptor-mediated drug delivery to macrophages in chemotherapy of leishmaniasis.

Methotrexate coupled to maleylated bovine serum albumin was taken up efficiently through the "scavenger" receptors present on macrophages and led to selective killing of intracellular Leishmania mexicana amazonensis amastigotes in cultured hamster peritoneal macrophages. The drug conjugate was nearly 100 times as effective as free methotrexate in eliminating the intracellular parasites. Furthermore, in a model of experimental cutaneous leishmaniasis in hamsters, the drug conjugate brought about more than 90% reduction in the size of footpad lesions within 11 days. In contrast, the free drug at a similar concentration did not significantly affect lesion size. These studies demonstrate the potential of receptor-mediated drug delivery in the therapy of macrophage-associated diseases.

Primary HIV Drug Resistance among Recently Infected Cases of HIV in North-West India.

BACKGROUND: Antiretroviral treatment may lead to the emergence of HIV drug resistance, which can be transmitted. HIV primary drug resistance (PDR) is of great public health concern because it has the potential to compromise the efficacy of antiretroviral therapy (ART) at the population level. OBJECTIVE: To estimate the level of primary drug resistance among recently infected cases of HIV in 6 ART centres of North-Western India from September 2014 to June 2016. METHODS: The level of primary drug resistance was studied among 37 recently infected HIV cases identified by Limiting antigen (Lag) avidity assay based on modified Recent Infection Testing Algorithm (RITA). The reverse transcriptase region of HIV-1 pol gene (1-268 codons) was genotyped. The sequences were analyzed using the Calibrated Population Resistance (CPR) tool of Stanford University HIV drug resistance (DR) database to identify drug resistance. RESULTS: Among 37 isolates studied, 6 (16.2%) samples showed primary drug resistance (PDR) against reverse transcriptase (RT) inhibitor. The proportion of primary drug resistance was 22.2% (2/9) among female sex workers, 14.3% (1/7) among men having sex with men, and 14.3% (3/21) among injecting drug users. Observed mutations were K219R, L74V, K219N, and Y181C. Injecting drug user (IDU) has showed resistance to either nucleoside/nucleotide reverse transcriptase inhibitors (NRTI) or nonnucleotide reverse transcriptase inhibitors (NNRTI). CONCLUSION: Resistance to either NRTI or NNRTI among the recently is a new challenge that needs to be addressed. The fact that both Y181C isolates are IDUs is important and represents 2/21 (~10%) NNRTI drug resistance. Surveillance for primary drug resistance (PDR) needs to be integrated into next generation of HIV surveillance as access to ART is increasing due to introduction of test and treat policy.

Experimentally induced various inflammatory models and seizure: understanding the role of cytokine in rat.

BACKGROUND: The mechanism of epileptogenesis is not well established. There is higher incidence of seizures among patients with chronic inflammatory disease. Cytokines are rapidly induced in the brain after a variety of stimuli including inflammation. Aim of this study was to produce various inflammatory models and seizure to understand the role of TNFalpha in above mentioned models. MATERIALS AND METHODS: A total of 54 male rats were included in the study. Animals were divided into 3 groups of colitis, arthritis, and cotton wool granuloma. Each group had 3 subgroups of control, model and treatment. At the end of 3 days in colitis, 17 days in arthritis and 7 days in cotton wool granuloma groups a subconvulsive dose of PTZ (40 mg/kg i.p) was injected to note seizure onset and seizure score. Brain samples were subjected to DNA fragmentation testing. Presence of inflammation was confirmed by morphology and histology. Plasma and brain TNFalpha levels were measured. RESULTS: The models of colitis, arthritis and CWG were effectively produced as evidenced by morphology and histology scores (p<0.001). Seizure onset was reduced and grade was increased (p<0.001). Thalidomide reduced the morphological, histological (p<0.002), DNA fragmentation and seizure grade (p<0.001) while increased seizure onset (p<0.001) in the arthritis group. TNFalpha levels in both plasma and brain were reduced following thalidomide treatment (p<0.002) in arthritis group. There were no significant findings in colitis or cotton wool granuloma groups. CONCLUSION: Inflammation was associated with decreased threshold to PTZ induced seizure. Thalidomide is effective in reducing the extent of arthritis as well as reducing the seizure scoring and increasing seizure onset in the adjuvant arthritis group. Thalidomide was also effective in reducing TNFalpha levels thus contributing to its antiepileptic activity.

Electron field emission from graphitic nanoflakes grown over vertically aligned carbon nanotubes.

Single step growth of self-assembled graphitic nanoflakes (GNF) over carbon nanotubes (CNT) on iron coated silicon(100) substrates is reported. These nanostructures were grown by varying the deposition time in a microwave plasma enhanced chemical vapor deposition reactor using acetylene, hydrogen and argon as reactant gases. Scanning electron microscope (SEM) studies of the deposited carbon films revealed that with increase in deposition time from 3 minutes to 6 minutes, the surface topography of the films transformed from one dimensional cylindrical nanostructure to flat-shaped two-dimensional nanoflakes. Carbon film deposited for 5 minutes showed improved surface coverage as compared to films deposited for 6 minutes i.e., surface area of the CNT film covered with nanoflakes increased as compared to carbon film deposited for higher durations. Field emission studies of films deposited at 5 minutes and 6 minutes showed increase in turn-on field, required for electron emission, from 2.7 V/microm to 2.9 V/microm respectively. However, such a combination of one dimension carbon and two dimension carbon may prove useful in applications where high surface area films are required.

Structural investigations of mode of action of drugs: structure and conformation of a novel peptidyl nucleoside antibiotic chryscandin hydrochloride pentahydrate.

The structure and conformation of antibiotic chryscandin, a structural analog of the terminus 3'-aminoacyladenylate moiety of tRNA, has been determined. The crystals belong to orthorhombic space group P2(1)2(1)2(1). The structure was refined to an R value of 0.065 for 1872 reflections. The structure and conformation has been compared with that of puromycin. The sugar pucker is different from that of puromycin, thus creating different orientation of peptide group with respect to nucleoside. All the water molecules are involved in hydrogen bonding. The crystal is also stabilized by stacking of adenine bases and p-methoxyphenyl rings. The results will be helpful in understanding structure-biological activity relationships, identification of inhibitors of metallopeptidases, and how chryscandin interacts with ribosomal units.

Optical magnetic circular dichroism in threshold photoemission from a magnetite thin film.

Threshold photoemission excited by polarization-modulated ultraviolet femtosecond laser light is exploited for phase-sensitive detection of magnetic circular dichroism (MCD) for a magnetite thin film. Magnetite (Fe(3)O(4)) shows a magnetic circular dichroism of ∼(4.5 ± 0.3) × 10(-3) for perpendicularly incident circularly polarized light and a magnetization vector switched parallel and antiparallel to the helicity vector by an external magnetic field. The asymmetry in threshold photoemission is discussed in comparison to the magneto-optical Kerr effect. The optical MCD contrast in threshold photoemission will provide a basis for future laboratory photoemission studies on magnetic surfaces.

Expression of interferon-gamma- inducible protein-10 and its receptor CXCR3 in chronic pancreatitis.

AIM: The role of CXC chemokine, interferon-gamma-inducible protein-10 and its receptor CXCR3 in pathophysiology of chronic pancreatitis (CP) is not very clear. Hence, this study was carried out to analyze the expression of CXCL10 and CXCR3 in CP tissues. METHODS: Pancreatic tissues from 25 histopathologically graded CP cases (11 alcohol associated CP, 5 confirmed idiopathic and 9 of undefined nature) and 10 normal cases were studied. Tissues were subjected to real-time PCR, immunohistochemistry, and Western blot analysis for CXCL10 and CXCR3 expression. RESULTS: Real-time (RT)-PCR revealed increased expression of CXCL10 (13-fold) and CXCR3 (7-fold) in CP tissue. The immunohistochemistry and Western blot analysis of the same showed significant increased protein expression and correlated well with the histopathological grades. The CXCL10 was localized mainly in the cytoplasm of pancreatic acinar cells and expression increased from grade I to grade II and declined in grade III while no expression was recorded in normal. The CXCR3 was expressed strongly at the acinar cell membrane in CP as compared to normal. Further, comparative analysis by semiquantitative RT-PCR analysis was performed for other CXC/CC chemokines (CXCL9, CXCL11, CCL3, CCL4, CCL5) and receptor (CCR5) which revealed their upregulation in the diseased state. CONCLUSION: The existence of CXCL10 and CXCR3 with other CXC/CC chemokine signature in CP is suggestive of their vital role in the progression of chronic inflammation.

Prevalence of high--risk human papillomavirus infections in women with benign cervical cytology: a hospital based study from North India.

INTRODUCTION: Cervical cancer is the commonest cancer among Indian women. High-risk human papillomavirus (HPV) detection holds the potential to be used as a tool to identify women, at risk for subsequent development of cervical cancer. There is a pressing need for identifying prevalence of asymptomatic cervical HPV infection in the local population. OBJECTIVE: To determine the prevalence of high-risk HPV DNA in women with benign cervical cytology. MATERIALS AND METHODS: Women visiting the gynecology outpatient with varied complaints were subjected to Pap smear. Four hundred and seventy two samples were subjected to polymerase chain reaction, using consensus primers for low and high-risk HPV (types 6, 11, 16, 18, 31 and 33). The samples that were positive for HPV DNA were subsequently assessed for high-risk consensus primers, types 16, 18, 31 and 33 as well as for HPV type 16 and 18. RESULTS: One hundred and seventy four (36.8%) women tested positive for HPV DNA. Thirty nine (8.2%) of the entire cohort tested positive for high-risk HPV. Fifteen samples were positive for type 16, 22 for type 18 and two for both types 16 and 18. A statistically higher prevalence of high-risk HPV was observed in poorly educated and rural groups. No association of HPV prevalence was noted with age, parity and age at marriage. CONCLUSION: The study generates epidemiological data of prevalence of sub-clinical HPV in the women visiting a tertiary care institute as well as peripheral health centres. The data generated will be useful for laying guidelines for mass screening of HPV, treatment and prophylaxis in the local population.

Detection of high-risk human papillomavirus type 16/18 in cutaneous warts in immunocompetent patients, using polymerase chain reaction.

Cutaneous warts are caused by human papillomavirus (HPV). Prevalence studies of the types of HPV present in cutaneous warts have been carried out more frequently in immunosuppressed patients. The present study was designed to study the association of high-risk HPV in cutaneous warts of immunocompetent patients. A total of 45 cases of cutaneous warts from various sites in immunocompetent subjects were analyzed for HPV. Samples included both archival material i.e., paraffin embedded and fresh tissue. Highly sensitive and comprehensive polymerase chain reaction (PCR) methodology for detection of HPV of high oncogenic potential, HPV 16/18, was employed. Human papillomavirus 16 was detected in 3 (6.6%) patients. None of the lesions demonstrated HPV 18. None of the cutaneous warts demonstrated histopathological features associated with dysplasia or neoplasia. The identification of HPV 16 in cutaneous warts, which are benign proliferations of the skin, further expands the spectrum of HPV-linked lesions. It remains of critical interest to determine whether these types are specifically associated with the development of malignant lesions analogous to those seen in anogenital cancer.

Effect of Sapindus trifoliatus on hyperalgesic in vivo migraine models.

Phytotherapies have offered alternative sources of therapy for migraine and gained much importance in prophylactic treatment. Sapindus trifoliatus is a medium-sized deciduous tree growing wild in south India that belongs to the family Sapindaceae. The pericarp is reported for various medicinal properties. A thick aqueous solution of the pericarp is used for the treatment of hemicrania, hysteria or epilepsy in folklore medicine. We have investigated the antihyperalgesic effects of the lyophilized aqueous extract of S. trifoliatus in animal models predictive of experimental migraine models using morphine withdrawal-induced hyperalgesia on the hot-plate test and on 0.3% acetic acid-induced abdominal constrictions in adult male Swiss albino mice. The extract significantly (N = 10, P < 0.05) increased the licking latency in the hot-plate test when administered i.p. at 10 mg/kg (6.70 +/- 0.39 s in saline control vs 18.76 +/- 0.96 s in S. trifoliatus-treated animals) and significantly (N = 10, P < 0.001) reduced the abdominal constrictions when administered i.p. at 2 and 10 mg/kg (40.20 +/- 1.36 in saline control vs 30.20 +/- 1.33 and 23.00 +/- 0.98 for 2 and 10 mg/kg, i.p., respectively, in S. trifoliatus-treated animals). Furthermore, when administered i.p. at 20 and 100 mg/kg, the extract significantly (N = 10, P < 0.05) inhibited the apomorphine-induced climbing behavior in mice (climbing duration 15.75 +/- 5.0 min for saline control vs 11.4 +/- 1.28 and 3.9 +/- 1.71 min for 20 and 100 mg/kg, respectively, in S. trifoliatus-treated animals). In receptor radioligand-binding studies, the extract exhibited affinity towards D2 receptors. The findings suggest that dopamine D2 antagonism could be the mechanism involved in the antihyperalgesic activity of the aqueous extract of S. trifoliatus.

Pharmacological studies of the aqueous extract of Sapindus trifoliatus on central nervous system: possible antimigraine mechanisms.

The aqueous extract of pericarp of fruits of Sapindus trifoliatus (ST) Linn., family Sapindaceae was evaluated for its potential effects on central nervous system in mice. The extract at doses 20 and 100 mg/kg, i.p. significantly (p < 0.001) reduced the spontaneous locomotor activity and at 100 mg/kg, increased the thiopental-induced sleeping time. In rota-rod motor co-ordination test, ST at 100 mg/kg, i.p. significantly (p < 0.05-0.01) reduced the endurance time. Further ST exhibited no protection against maximal electroshock (MES)- and pentylenetetrazole (PTZ)-induced convulsions in mice. In receptor radioligand binding studies, ST exhibited affinity towards dopaminergic, alpha-adrenergic and muscarnic receptors. The findings suggest that, ST may possess principles with potential neuroleptic properties.

Incidence of lamivudine resistance associated mutations in pol-gene of HIV-1 in patients from north India: a preliminary report.

Screening of drug-resistant variants is very important for the effective clinical management of HIV-infected patients and development of new strategies. The present study was aimed to detect codon-184 mutations in the pol-gene of HIV leading to resistance to lamivudine (3-TC) by nested cum ARMS-PCR approach in 10 treated and 9 treatment naive patients. For correlation the whole blood CD4/CD8 cell counts and the soluble TNFRII levels in plasma were also determined. Of the 19 patients tested, mutant variants were observed in 2 patients (Met Val in one and Met Val & lle in second) both being treated with 3-TC. No mutations were detected in the treatment-naive patients. The results confirmed that, drug resistant variants of codon-184 emerge rapidly in patients receiving 3-TC containing regimens including our population, which is mainly infected with subtypeC of the virus that could be detected along with wild viral population using sensitive approaches such as ARMS-PCR.