Expression profiles of different cytokine genes in peripheral blood mononuclear cells of goats infected experimentally with native strain of Mycobacterium avium subsp. paratuberculosis

Paratuberculosis (ParaTB), caused by Mycobacterium avium subspecies paratuberculosis (MAP) is a chronic enteritis of ruminants and may contribute to Crohn's disease in humans. Key features of host immunity to MAP infection include an early pro-inflammatory (Th1-like) response that eventually gives way to a predominant anti-inflammatory (Th2-like) response. Many studies have been conducted to understand the underlying mechanism of misdirected host immune response, however, these studies mainly focused on cattle. The present study is the first attempt to test the hypothesis of shift in Th1 to Th2 like responses during the progression of ParaTB in caprine species (small ruminant). Ten healthy male kids (<6 months old) of the same breed were selected for this study. Of the 10 kids, 6 were experimentally infected with native strain (S5) of MAP ("Indian Bison Type") and the remaining 4 kids were control. Kids were monitored for a period of 12 months post infection (MPI) and were tested for establishment of infection. Expression levels of IFNG, IL2, IL12, IL4, and IL10 genes were estimated before infection and at 4, 8, and 12 MPI in stimulated peripheral blood mononuclear cells (PBMCs) of infected and control kids. The study demonstrated the expression of IFNG and IL2 as classic Th1-like pro-inflammatory signatures; whereas, IL10 exhibited itself as classical Th2-like signature. The study also reports unexpected lowered expression of the IL12 gene simultaneously with increased expression of IFNG, lowered expression of the IL2 gene (compared to IFNG), and suppressed expression of the IL4.

Vitamin D levels during and after resolution of ketoacidosis in children with new onset Type 1 diabetes

AIM

To study the effect of ketoacidosis on measured 25-hydroxyvitamin D3 in children with new onset Type 1 diabetes.

METHODS

Measurement of pH and bicarbonate levels was carried out in children with newly diagnosed Type 1 diabetes at presentation with ketoacidosis. 25-hydroxyvitamin D3 estimation was carried out at presentation (timepoint 1) and 1 month later (timepoint 2). There was no significant difference in the mean (±sd) 25-hydroxyvitamin D3 levels [35.39 (±25.79) vs 39.63 (±48.03) nmol/L; P = 0.661) at the two timepoints in the study.

RESULTS

Correlation analysis revealed a positive correlation between bicarbonate levels and timepoint 1, i.e. the lower the bicarbonate levels, the lower were the timepoint 1 levels and vice versa (correlation coefficient 0.538, P = 0.001). Timepoint 2 levels also showed a positive correlation with serum bicarbonate levels with a correlation coefficient of 0.379 (P = 0.032). None of the variables other than bicarbonate,.(age, gender, BMI, pH or time), was found to have the predictive ability for timepoint1 levels. Similarly for predicting timepoint 2 levels, BMI was found to have independent predictive ability in addition to bicarbonate.

CONCLUSIONS

Severe ketoacidosis, as judged by bicarbonate but not pH, may transiently lower 25-hydroxyvitamin D3 levels in children with new onset Type 1 diabetes. Persistence of low 25-hydroxyvitamin D3 levels after resolution of ketoacidosis suggests a state of permanent vitamin D deficiency in our patient population.

Limits on spin-independent couplings of WIMP dark matter with a p-type point-contact germanium detector

We report new limits on a spin-independent weakly interacting massive particle (WIMP)-nucleon interaction cross section using 39.5 kg days of data taken with a p-type point-contact germanium detector of 840 g fiducial mass at the Kuo-Sheng Reactor Neutrino Laboratory. Crucial to this study is the understanding of the selection procedures and, in particular, the bulk-surface events differentiation at the sub-keV range. The signal-retaining and background-rejecting efficiencies were measured with calibration gamma sources and a novel n-type point-contact germanium detector. Part of the parameter space in the cross section versus WIMP-mass implied by various experiments is probed and excluded.

Effect of physiologically relevant heat shock on development, apoptosis and expression of some genes in buffalo (Bubalus bubalis) embryos produced in vitro

For investigating the effects of physiologically relevant heat shock, buffalo oocytes/embryos were cultured at 38.5°C (control) or were exposed to 39.5°C (Group II) or 40.5°C (Group III) for 2 h once every day throughout in vitro maturation (IVM), fertilization (IVF) and culture (IVC). Percentage of oocytes that developed to 8-cell, 16-cell or blastocyst stage was lower (p < 0.05) and the number of apoptotic nuclei was higher (p < 0.05) for Group III > Group II > controls. At both 8-16-cell and blastocyst stages, relative mRNA abundance of stress-related genes HSP 70.1 and HSP 70.2 and pro-apoptotic genes CASPASE-3, BID and BAX was higher (p < 0.05) in Groups III and II than that in controls with the exception of stress-related gene HSF1. Expression level of anti-apoptotic genes BCL-XL and MCL-1 was also higher (p < 0.05) in Groups III and II than that in controls at both 8-16-cell and blastocyst stages. Among the genes related to embryonic development, at 8-16-cell stage, the expression level of GDF9 was higher (p < 0.05) in Group III than that in controls, whereas that of GLUT1, ZAR1 and BMP15 was not significantly different among the three groups. At the blastocyst stage, relative mRNA abundance of GLUT1 and GDF9 was higher (p < 0.05) in Group II than that in controls, whereas that of ZAR-1 and BMP15 was not affected. The results of this study demonstrate that exposure of buffalo oocytes and embryos to elevated temperatures for duration of time that is physiologically relevant severely compromises their developmental competence, increases apoptosis and affects stress-, apoptosis- and development-related genes.

In vitro culture and morphological characterization of prepubertal buffalo (Bubalus bubalis) putative spermatogonial stem cell

PURPOSE

Spermatogonial stem cells (SSCs) have the unique ability both to self-renew and to produce progeny that undergo differentiation to spermatozoa. The present study has been carried out to develop a method to purify and enrich the pure populations of spermatogonial stem cell like cells in buffalo.

METHODS

The spermatogonial cells were isolated from testes of 3-7 month old buffalo calves and disaggregated by double enzymatic digestion. Mixed population of isolated cells were then plated on Datura stramonium agglutinin (DSA) lectin coated dishes for attachment of Sertoli cells. The desired cells were obtained from suspension medium after 18 h of incubation and then loaded on discontinuous density gradient using percoll (20-65 %) and different types of spermatogonia cells were obtained at interface of each layer. These cells were cultured in vitro.

RESULTS

Spermatogonial cells isolated have spherical outline and two or three eccentrically placed nucleoli, created a colony after proliferation during first week or immediately after passage. After 7-10 days of culture, the resulted developed colonies of spermatogonial cells expressed the spermatogonial specific genes like Plzf and VASA; and other pluripotency related markers viz. alkaline phosphtase, DBA, CD9, CD90, SSEA-1, OCT-4, NANOG and REX-1.

CONCLUSION

Our results show that the isolated putative spermatogonial stem cells exhibit the expression of pluripotency related and spermatogonial specific genes. This study may help to establish a long term culture system for buffalo spermatogonia.

A randomized controlled clinical trial to compare the safety and efficacy of edaravone in acute ischemic stroke

Background and Objective:

Edaravone has potent antioxidant and free radical scavenger properties. Few Japanese studies had demonstrated its neuroprotective role in acute ischemic stroke (AIS). This study aims to evaluate the efficacy of edaravone in terms of functional outcome in a group of Indian patients of AIS.

Materials and Methods:

Fifty patients of AIS were randomly divided into two groups. The study group received 30 mg of edaravone twice daily for 14 days by infusion, while control group received normal saline infusion as placebo. Outcome assessment was done by the Modified Rankin Scale (MRS). MRS score ≤2 at 90 days was considered as a favorable outcome.

Results:

Of 25 patients, 18 (72%) had favorable outcomes (MRS ≤2) at 90 days in edaravone group, while 10 (40%) of 25 patients in placebo group had favorable outcome (P < 0.005). Two patients expired (one in each group) during treatment. The mean Barthel index increased from 41.20 ± 32.70 at baseline to 82.40 ± 18.32 at day 90 in edaravone group as compared with placebo group in which scores were 44.20 ± 22.76 at baseline and 68.20 ± 21.30 at day 90 (P < 0.005).

Conclusions:

We therefore conclude that edaravone effectively improves functional outcome in AIS.

Buffalo (Bubalus bubalis) ES cell-like cells are capable of in vitro skeletal myogenic differentiation

When buffalo embryonic stem (ES) cell-like cells that expressed surface markers SSEA-4, TRA-1-60, TRA-1-81, CD9 and CD90 and intracellular markers OCT4, SOX2 and FOXD3, as shown by immunofluorescence, and that expressed REX-1 and NUCLEOSTEMIN as confirmed by RT-PCR, were subjected to suspension culture in hanging drops in absence of LIF and buffalo foetal fibroblast feeder layer support, they differentiated to form three-dimensional embryoid bodies (EBs). Of 231 EBs examined on Day 3 of suspension culture, 141 (61.3 ± 3.09%) were of compact type, whereas 90 (38.4 ± 3.12%) were of cystic type. The cells obtained from EBs were found to express NF-68 and NESTIN (ectodermal lineage), BMP-4 and α-skeletal actin (mesodermal lineage), and α-fetoprotein, GATA-4 and HNF-4 (endodermal lineage). When these EBs were cultured on gelatin-coated dishes, they spontaneously differentiated to several cell types such as epithelial- and neuron-like cells. When EBs were cultured in the presence of 1 or 2% DMSO or 10(-8) M or 10(-7) M retinoic acid for 25 days, ES cells could be directed to form muscle cell-like cells, the identity of which was confirmed by expression of α-actinin by immunofluorescence and of MYF-5, MYOD and MYOGENIN genes by RT-PCR. MYOD was first detected on Day 10 in both treatment groups and on Day 15 in controls, whereas MYOGENIN was first detected on Day 10, Day 15 and Day 25 in the presence of retinoic acid, in the presence of DMSO and in controls, respectively. The present study demonstrates the ability of buffalo ES cell-like cells to undergo directed differentiation to cells of skeletal myogenic lineage.

Transnasal K-wire to stabilise a complex zygomatic fracture: a forgotten method of fixation

Zygomatic complex fractures make up approximately 60% of facial fractures. The vast majority treated surgically use titanium miniplates. These require longer operating times and facial incisions to access the fracture. The use of a K-wire was first described 60 years ago. As a new generation of surgeons emerges, it is important to be aware of the various techniques available to increase their surgical armamentarium. One of its benefits is that it has a significantly reduced operative time and does not require any incisions.

Bioefficacy evaluation of controlled release formulations based on amphiphilic nano-polymer of carbofuran against Meloidogyne incognita infecting tomato

In the present investigation, the bioefficacy of developed carbofuran formulations, with PEG-600 (7a, CP1) & PEG-900 (7b, CP2) @ 5, 10 and 20 ppm, along with commercial formulation of carbofuran 3G (CP0) were evaluated against the root-knot nematode, Meloidogyne incognita infecting tomato (cv. Pusa Ruby) in pot and field conditions. The bioefficacy data indicated that the formulations developed by utilizing polymers having PEG - 900 (7b) as hydrophilic segment were effective even at 14 days post inoculation (dpi) as evident from shoot and root length. Also, the reduction in penetration was found to be maximum with CP2 (3.6 - 4.6 J2s) at all concentrations compared to CP1 (6.6-16.4 J2s) and CP0 (29.3-32.6 J2s). Overall, CP2 was more effective in reducing the number of nematodes up to 14 days, compared to CP1 and CP0. Both the CR formulations (CP1 and CP2) in general significantly reduced the number of galls, when compared to CP0. However, under field conditions, lower concentrations (5, and 10 ppm) of CP2, were less effective in controlling the gall formation whereas, CP2 at 20 ppm, was most effective than other treatments. The study revealed that the developed CR formulations of carbofuran have the potential for effective management of M. incognita in tomato under field conditions.

High prevalence of Mycobacterium avium subspecies paratuberculosis ('Indian bison type') in animal attendants suffering from gastrointestinal complaints who work with goat herds endemic for Johne's disease in India

OBJECTIVES

In this study we aimed to estimate the prevalence of Mycobacterium avium subspecies paratuberculosis (MAP) in animal attendants who were chronic colitis patients or who had inflammatory bowel disease and were suspected for Crohn's disease; these animal attendants worked with goat herds endemic for Johne's disease. Microscopic examination and culture tests were used. For comparison purposes a group of healthy human subjects (not suffering with colitis) was also screened.

METHODS

Stool samples obtained from 98 human subjects (58 animal attendants suspected for Crohn's disease and 40 healthy humans) were screened for the presence of MAP by microscopic examination and culture. Of the 58 animal attendants screened, 38 had abdominal pain, 29 had suffered episodes of diarrhea, 39 had experienced weight loss, 27 had fever, and 32 had a history of raw milk consumption. Animal attendants had had contact of variable duration with goat herds endemic for Johne's disease (1-5, 6-10, 11-15, and >15 years). Forty stool samples from healthy humans with no symptoms/history of contact with animals were also screened. IS900 PCR and IS1311 PCR restriction endonuclease analysis were used to characterize and genotype the MAP colonies.

RESULTS

MAP was recovered from 34 of the 98 human subject stool samples (34.7%). Of the 98 samples, 16.3% (n=16) were acid-fast. None of the 40 healthy human subjects were positive for MAP by microscopy, but five (12.5%) were positive for MAP by culture. Of the 58 animal attendants, 16 (27.6%) were positive by microscopy and 29 (50%) were positive by culture. MAP were recovered from 68.4% of animal attendants with abdominal pain, 72.4% of those with diarrhea, 71.8% of those with weight loss, 44.4% of those with fever, and 46.9% of those who had a history of raw milk consumption. Of the 29 culture-positive animal attendants, 48.3% had worked for >15 years, 27.6% for 11-15 years, 20.7% for 6-10 years, and 3.4% for 1-5 years with goat herds endemic for Johne's disease. Of the 34 culture isolates, 28 (82.4%) showed good quality DNA on agarose gel and were positive by IS900 PCR. Of the 28 IS900-positive DNA samples, 23 (82.1%) were genotyped as 'Indian bison type' and five (17.9%) as 'cattle type'.

CONCLUSIONS

The prevalence of MAP was higher in attendants suffering from gastrointestinal problems who worked with goat herds endemic for Johne's disease, than in humans with no history of contact with animals. The risk of developing gastrointestinal problems with clinical symptoms indistinguishable from inflammatory bowel disease was higher in humans who were in contact with goat herds endemic for Johne's disease as compared to healthy humans, and the risk was correlated with the duration of association with the endemic goat herds.

Derivation of buffalo embryonic stem-like cells from in vitro-produced blastocysts on homologous and heterologous feeder cells

PURPOSE

The aim of the present study is to compare the ability of homologous and heterologous embryonic fibroblast feeder layers to support isolation and proliferation of buffalo ES-like cells generated from hatched and expanded blastocysts produced by in vitro fertilization and characterization of derived cells through expression of pluripotent markers.

METHODS

Embryonic stem cells were derived from hatched and expanded blastocysts through intact blastocyst culture and enzymatic method respectively and compared for proliferation rate on homologous (buffalo) and heterologous feeder layers (goat and sheep).

RESULTS

A total of 69 hatched and 83 expanded blastocysts were used for isolation of inner cell masses which were seeded on buffalo, goat and sheep embryonic feeder layers. Following seeding, attachment rate, primary colony formation rate and survival to maximum number of passages were observed to be higher on homologous feeder layers.

CONCLUSIONS

Upon comparison of different feeder layer cells for derivation and maintenance of buffalo ES-like cells from hatched and expanded blastocysts, buffalo embryonic fibroblast cells were able to provide a better environment for maintaining pluripotency in culture conditions.

Buffalo (Bubalus bubalis) embryonic stem cell-like cells and preimplantation embryos exhibit comparable expression of pluripotency-related antigens

In this study, inner cell mass (ICM) cells were isolated from in vitro produced buffalo blastocysts and were cultured on mitomycin-C treated buffalo foetal fibroblast feeder layer for producing embryonic stem (ES) cells. Among different sources (hatched vs expanded blastocysts) or methods (enzymatic vs mechanical), mechanical isolation of ICM from hatched blastocysts resulted in the highest primary colony formation rate and the maximum passage number up to which ES cells survived. Putative ES cells expressed alkaline phosphatase and exhibited a normal karyotype up to passage 7. Putative ES cells and embryos at 2- to 4-cell, 8- to 16-cell, morula and blastocyst stages strongly expressed stage-specific embryonic antigen (SSEA)-4 but lacked expressions of SSEA-1 and SSEA-3. Putative ES cells also expressed tumour rejection antigen (TRA)-1-60, TRA-1-81 and Oct4. Whereas in all early embryonic stages, TRA-1-60 was observed only in the periplasmic space, and TRA-1-81 expression was observed as small spots at a few places inside the embryos, both these markers were expressed by ICM. Oct4 expression, which was observed at all the embryonic stages and also in the trophectoderm, was the strongest in the ICM. Buffalo putative ES cells possess a unique pluripotency-related surface antigen phenotype, which resembles that of the ICM.

Intracranial tuberculomas in patients with tuberculous meningitis: predictors and prognostic significance

SETTING

Intracranial tuberculomas are commonly observed neuroimaging abnormalities in tuberculous meningitis (TBM).

OBJECTIVE

to evaluate the predictors and prognostic significance of tuberculomas in patients with TBM.

DESIGN

In a retrospective follow-up study, contrast-enhanced magnetic resonance imaging was performed at study inclusion and after 9 months of follow-up. Univariate analysis and multivariate analysis were used to identify predictive factors for tuberculoma. Prognosis (death and severe disability) was assessed using the modified Rankin scale.

RESULTS

At inclusion, 43 of 110 patients had cerebral tuberculomas. Seven patients developed paradoxical tuberculomas. Predictors of tuberculomas were raised cerebrospinal fluid (CSF) protein (>3 g/l) and meningeal enhancement. Multivariate analysis did not show any significant predictors. During follow-up, the only significant predictor of paradoxical development of tuberculomas was raised CSF protein (>3 g/l). After 9 months of follow-up, 32 patients had died or had severe disability. Survival analysis revealed that patients with tuberculomas and those without tuberculomas had a similar prognosis.

CONCLUSION

Tuberculomas occurred in approximately 39% of the patients with TBM. Significant predictors were meningeal enhancement and raised CSF protein. TBM patients with or without tuberculomas had a similar prognosis.

Nerve conduction studies in paucibacillary and multibacillary leprosy: a comparative evaluation

Involvement of peripheral nerves in patients with leprosy results in sensory, motor and autonomic dysfunctions along with deformities and disability. Pattern of nerve involvement is different for different forms of leprosy. In this study, we evaluated and compared the nerve conduction parameters of paucibacillary leprosy with that of multibacillary leprosy. In this study, 40 consecutive patients of leprosy (19 cases of paucibacillary and 21 cases of multibacillary leprosy) were included. Nerve conduction studies were performed according to the standard procedure described in the manual of the machine. We observed that patients with multibacillary leprosy had significantly more severe changes in nerve conduction parameters as compared to that of paucibacillary leprosy. In paucibacillary leprosy, the dominant pattern of nerve involvement was that of mononeuropathy, however, in 6 paucibacillary cases the nerve involvement was in form of mononeuritis multiplex. Electrophysiological assessment also revealed involvement of clinically uninvolved nerves. Nerve conduction parameters were suggestive of mixed axonal as well as demyelination of the peripheral nerves.

Cysticercal encephalitis with cortical blindness

The authors report a 6-year-old boy, who had presented with low-grade fever, altered sensorium, headache and seizure for 5 days. On examination, he had features of raised intracranial pressure with left VI cranial-nerve palsy and bilateral extensor plantar response. CT scan showed multiple calcifications in cerebral cortex. MRI cranium showed multiple cysts involving whole of the brain. He was diagnosed as having cysticercal encephalitis, based on immunological and imaging study. He was managed with 20% mannitol, phenytoin and albendazole, and regained consciousness 7 days later, but had residual neurological deficit as left-lower-limb monoparesis and visual acuity of just projection of rays (PR+) and perception of light (PL+).

Predictors of stroke in patients of tuberculous meningitis and its effect on the outcome

BACKGROUND

Stroke is a devastating complication of tuberculous meningitis and is an important determinant of its outcome.

AIM

To prospectively evaluate the predictive factors for stroke in patients with tuberculous meningitis and to assess the impact of stroke on the overall prognosis and outcome.

METHODS

We evaluated and followed 100 patients of tuberculous meningitis for 6 months. Magnetic resonance imaging was performed at inclusion and after 6 months. We evaluated the predictors of stroke and also assessed the effect of stroke on the outcome. Outcome was defined with the help of modified Rankin scale.

RESULTS

Of the 100 patients, 6 lost to follow-up. Thirty patients had stroke, 27 of them had stroke at inclusion. Three patients developed stroke during follow-up. In most of the patients, stroke was a manifestation of advanced stages of tuberculous meningitis. Internal capsule/basal ganglia were the most frequently involved sites. Infarcts commonly involved the middle cerebral arterial territory. On univariate analysis, predictors of stroke were aged >25 years (P < 0.001), cranial nerve involvement (P < 0.001), sylvian fissure exudates (P = 0.026), posterior fossa exudates (P = 0.016), optic chiasmal exudates (P = 0.04) and vision impairment (P = 0.004). Stage III tuberculous meningitis (P < 0.001) was also a predictor of stroke. On multivariate analysis aged >25 years was found a significant predictor of stroke. Strokes in patients with tuberculous meningitis were associated with poor prognosis.

CONCLUSION

Stroke occurred in 30% of cases with tuberculous meningitis. Advanced stage of tuberculous meningitis, basal exudates, optochiasmatic arachnoiditis and vision impairment were significant predictors of stroke. Stroke independently predicted the poor outcome of tuberculous meningitis.

Microwave synthesis and antifungal evaluations of some chalcones and their derived diaryl-cyclohexenones

Microwave irradiation (MWI) of acetophenones and substituted benzaldehydes in water resulted in a "green-chemistry" procedure for the preparation of chalcones (1-14), through base catalyzed Claisen-Schmidt condensation reaction, in good yields. Further 3,5-diaryl-6-carbethoxy-2-cyclohexen-1-ones (1a-14a) were prepared through base catalyzed cyclocondensation of above chalcones with ethylacetoacetate using MWI as the energy source and silica as support. Out of fourteen cyclohexenones, ten (1a, 4a, 5a, 6a, 7a, 9a, 10a, 11a, 12a and 13a) are reported for the first time in literature. The synthesized compounds were characterized using various spectroscopic techniques, viz. ((1)H NMR and IR) and screened for their antifungal activity in vitro against Sclerotium rolfsii and Rhizoctonia solani by poisoned food technique. The compounds tested were found to be active against R. solani whereas against S. rolfsii, moderate activity was observed, as evident from LC(50) values. The most potent compounds against R. solani were 1-(4-Fluoro-phenyl)-3-phenyl-propenone (13) and 1,3-Diphenyl-propenone (14) having LC(50) values of 2.36 and 2.49 mg L(- 1) respectively (LC(50) of Hexaconazole = 1.12 mg L(- 1)) and against S. rolfsii 3-(4-Fluoro-phenyl)-5-(3-nitro-phenyl)-6-carbethoxy-2-cyclohexen-1-one (12a) was most active having LC(50) value of 285 mg L(- 1)compared to Hexaconazole (LC(50) = 1.27 mg L(- 1)).

Mixed gonadal dysgenesis with normal karyotype: a rare case report

Mixed gonadal dysgenesis (MGD) presents as a unilateral testis, usually intraabdominal, a streak gonad on contralateral side, and persistent mullerian structures. 45X/45XY karyotype is most frequent in such cases with predominance of 45X cells in both peripheral lymphocytes and gonads. We present a rare case of a left undescended testis, normally descended right testis, with penoscrotal hypospadias, who had a normal karyotype and whose histopathological findings were endometrial tissue and fallopian tube in left testicular biopsy. Gonadal dysgenesis should always be kept a possibility in patient with undescended testis and proximal hypospadias. If karyotype reveals a 46XY gonadal dysgenesis, these patients need all the more careful follow-up to screen for gonadoblastoma in remaining normal testis. Subjecting the patients to prophylactic orchidectomy with hormone replacement can be an additional option in such patients.

Development of controlled release formulations of azadirachtin-A employing poly(ethylene glycol) based amphiphilic copolymers

Controlled release (CR) formulations of azadirachtin-A, a bioactive constituent derived from the seed of Azadirachta indica A. Juss (Meliaceae), have been prepared using commercially available polyvinyl chloride, polyethylene glycol (PEG) and laboratory synthesized poly ethylene glycol-based amphiphilic copolymers. Copolymers of polyethylene glycol and various dimethyl esters, which self assemble into nano micellar aggregates in aqueous media, have been synthesized. The kinetics of azadirachtin-A, release in water from the different formulations was studied. Release from the commercial polyethylene glycol (PEG) formulation was faster than the other CR formulations. The rate of release of encapsulated azadirachtin-A from nano micellar aggregates is reduced by increasing the molecular weight of PEG. The diffusion exponent (n value) of azadirachtin-A, in water ranged from 0.47 to 1.18 in the tested formulations. The release was diffusion controlled with a half release time (t(1/2)) of 3.05 to 42.80 days in water from different matrices. The results suggest that depending upon the polymer matrix used, the application rate of azadirachtin-A can be optimized to achieve insect control at the desired level and period.

Ferromagnetic behaviour of nickel contacted multiwalled carbon nanotubes

A novel method for the contact of ferromagnetic nano-nickel onto multiwalled carbon nanotubes (MWCNTs) is proposed in this work. The process involves the decomposition of the precursor: nickel carbonyl-Ni(CO)4 into nickel and CO by laser chemical vapour deposition at 150-200 degrees C and the deposition of nano-nickel onto MWCNTs. Field emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), HR (High resolution) TEM, and Raman spectroscopy were employed for the detailed analysis of the nickel contacted MWCNTs. The ferro-magnetic nature of the sample was confirmed by Super-conducting Quantum Interference Device (SQUID) analysis.

Synthesis and field emission properties of ultra-nanocrystalline diamond fibers and helices

We propose a novel template method for large scale synthesis of Ultra-Nanocrystalline Diamond (UNCD) fibres and helices with lengths of thousands of microns and diameters ranging from 0.5 to 5 microm: (i) Large quantities of submicrometer- or nanometer-diameter silica (a-SiO2) nanostructures, with lengths in the order of 2 to 4 mm, were synthesized by Vapor-Liquid-Solid (VLS) method; (ii) UNCD coating of as-synthesized a-SiO2 micro- or nanonanostructures by Microwave Plasma Chemical Vapour Deposition (MPCVD) technique in hydrogen-deficient condition. Electron Field Emission (EFE) of as-synthesized UNCD structures was observed with a threshold field of 3.4 V/microm. These micro- or nanostructures may find potential applications in high power electronics, vertical field-effect transistors in vacuum electronics, heat sinks in microelectronics and structural materials in Micro- and Nano-Electro-Mechanical Systems (MEMS/NEMS). The successful preparation of various types of UNCD structures suggests that this templating process can be used for a wide range of materials.

Synthesis and bioefficacy evaluation of new 3-substituted-3,4-dihydro-1,3-benzoxazines

A new series of 1, 3-Benzoxazines were synthesized, characterized ((1)H NMR and (13)C NMR) and evaluated for their pesticidal activity. Six new 3-alkyl-3, 4-dihydro-4-methyl-2H-1, 3-benzoxazines (1-6) were prepared by hydroxymethylation of secondary amines with formaldehyde in 65-68% yields. These compounds were screened for there IGR activity against Spodoptera litura and for antifungal fungal activity in vitro against Sclerotium rolfsii ITCC 6181 by poisoned food technique. Insect Growth Regulatory (IGR) activity against Spodoptera litura showed that compound 3-Nonyl-3,4-dihydro-4-methyl-2H-1,3-benzoxazines was most effective as IGR with larval GI(50) of 1.863 mu g/Insect. Compounds 3-Octyl-3,4-dihydro-4-methyl-2H-1,3-benzoxazines and 3-Decyl-3,4-dihydro-4-methyl-2H-1,3-benzoxazines were effective IGRs. Antifungal screening revealed that compound 3-Dodecyl-3, 4-dihydro-4-methyl-2H-1,3-benzoxazines, was highly effective against Sclerotium rolfsii with LC(50) value 31.7 mg L(-1) comparable with commercial fungicide Hexaconazole (LC(50) 1.27 mg L(-1)). Also compounds 3-Nonyl-3, 4-dihydro-4-methyl-2H-1,3-benzoxazines and 3-Decyl-3,4-dihydro-4-methyl-2H-1,3-benzoxazines displayed promising fungitoxicity. The results described in this paper are promising and provides new array of synthetic chemicals to be utilized as pesticides.