Long-Time Oxygen and Superoxide Localization in Arabidopsis thaliana Cryptochrome

Cryptochromes are proteins that are highly conserved across species and in many instances bind the flavin adenine dinucleotide (FAD) cofactor within their photolyase-homology region (PHR) domain. The FAD cofactor has multiple redox states that help catalyze reactions, and absorbs photons at about 450 nm, a feature linked to the light-related functions of cryptochrome proteins. Reactive oxygen species (ROS) are produced from redox reactions involving molecular oxygen and are involved in a myriad of biological processes. Superoxide O2•- is an exemplary ROS that may be formed through electron transfer from FAD to O2, generating an electron radical pair. Although the formation of a superoxide-FAD radical pair has been speculated, it is still unclear if the required process steps could be realized in cryptochrome. Here, we present results from molecular dynamics (MD) simulations of oxygen interacting with the PHR domain of Arabidopsis thaliana cryptochrome 1 (AtCRY1). Using MD simulation trajectories, oxygen binding locations are characterized through both the O2-FAD intermolecular distance and the local protein environment. Oxygen unbinding times are characterized through replica simulations of the bound oxygen. Simulations reveal that oxygen molecules can localize at certain sites within the cryptochrome protein for tens of nanoseconds, and superoxide molecules can localize for significantly longer. This relatively long-duration molecule binding suggests the possibility of an electron-transfer reaction leading to superoxide formation. Estimates of electron-transfer rates using the Marcus theory are performed for the identified potential binding sites. Molecular oxygen binding results are compared with recent results demonstrating long-time oxygen binding within the electron-transfer flavoprotein (ETF), another FAD binding protein.

Distribution of virulence genes and biofilm characterization of human isolates of Streptococcus agalactiae: A pilot study

This study included 21 newly isolated clinical samples of Streptococcus agalactiae (Group B Streptococcus) screened in patients (six male, fifteen female) from various states of India with different infections (urinary tract infections, blood, pus and eye infections). All isolates were identified as Group B Streptococcus (GBS) using hemolytic properties, serogrouping and MALDI-TOF-MS analysis. Six virulence genes, cfb (100%), cylE (90.4%), lmp (85.7%), bca (71.4%), rib (38%) and bac (4.7%) were detected via polymerase chain reaction (PCR). Distribution studies of these six genes revealed five isolates containing five virulence genes (23.8%), followed by ten isolates containing four virulence genes (47.6%). The twenty GBS isolates selected on the glass surface included non-biofilm producers (n = 6, 30%), weak (n = 11, 55%) and moderate biofilm producers (n = 3, 15%). On the polystyrene surface, weak (n = 4, 20%), moderate (n = 2, 10%) and strong (n = 14, 70%) biofilm producers were detected. Live-dead cell staining revealed that more viable cells accumulated in the S. ag 7420 isolate than in the AH1 isolate. Scanning electron microscope (SEM) biofilm analysis showed S. ag AH1 cells appeared as chain-like structures, whereas the S. ag 7420 isolate biofilm cells appeared as fork-like structures on the glass surface. Biofilm elements were analyzed using Energy Dispersive X-Ray Analysis (EDAX) for both isolates and 13 elements with different orders of composition were found. Thus, virulence gene detection, distribution and biofilm formation by these new clinical isolates suggested the virulent nature of these pathogens, which might cause different levels of disease severity in humans.

Preparation of an Intelligent pH Film Based on Biodegradable Polymers for Monitoring the Food Quality and Reducing the Microbial Contaminants

Hydrogel refers to a three-dimensional cross-linked polymeric network made of synthetic or natural polymers that can hold water in its porous structure. The inclusion of hydrophilic groups in the polymer chains, such as amino, carboxyl, and hydroxyl groups, contributes to the hydrogel's water-holding ability. At physiological temperature and pH, these polymeric materials do not dissolve in water, but they do swell significantly in aqueous media. Hydrogel can be manufactured out of almost any water-soluble polymer, and it comes in a variety of chemical compositions and bulk physical properties. Hydrogel can also be made in a variety of ways. Hydrogel comes in a variety of physical shapes, including slabs, microparticles, nanoparticles, coatings, and films. Due to its ease of manufacture and self-application in clinical and fundamental applications, hydrogel has been widely exploited as a drug carrier. Contact lenses, artificial corneas, wound dressing, suture coating, catheters, and electrode sensors are some of the biomedical applications of hydrogels. The pigment color changes were observed from colorless to pale pink followed by dark reddish-pink. Anthocyanin was produced in large quantities and tested using a UV-visible spectrophotometer. At 450-550 nm, the largest peak (absorbance) was detected, indicating the presence of anthocyanin. The FTIR analysis of this study shows the different stretches of bonds at different peaks: 2918.309 (-C-H alkane stretch), 2812.12 (-C-H aldehyde weak intensity), 192320.37/cm (C-O bend), 21915.50, 2029.08/cm (-C=C arene group), 1906.94/cm (=C-H aromatics), 1797.78/cm (=C-H), 1707.94 (-C=O ketene), 1579.70, 1382.96 (C-H alkane strong bend), 889.18/cm (C-H aromatics plane bend), and 412.77/cm (-C-CI strong bond). The spectra of the PVA/chitosan film depict the peak's formation: 1571.88, 1529.55, 1500.62/cm (C-H alkene strong bend), 1492.90, 1483.26, 1467.83/cm (C-H alkene strong bond), 670.48, 443.63, 412.77/cm (-O-H carboxylic acids with great intensity), 1708.93 (-C=O ketone), and 1656.0/cm (alkenyl C=C stretch strong bond).

Discrimination experienced by sexual minority males in Australia: Associations with suicidal ideation and depressive symptoms

INTRODUCTION

Discrimination has been under-examined as a social determinant of the higher rates of poor mental health experienced by sexual minorities. The objectives of our study were to: 1) assess whether discrimination was independently associated with poor mental health among sexual minority males, and 2) assess the potential mediation role of discrimination in the associations between sexual minority status and poor mental health.

METHODS

We used cross-sectional data on 13,230 males aged 18-55 years from the Australian Longitudinal Study on Male Health; bisexual and homosexual males comprised 1.5% and 1.6% of the sample, respectively. We fit Poisson regression and zero-inflated negative binomial regression models to examine suicidality, depressive symptoms and perceived discrimination in the past two years as correlates of suicidality and depressive symptoms.

RESULTS

Statistically significant differences were observed in the prevalence of perceived discrimination by sexual orientation (p < 0.001), with the highest prevalence among bisexual (29.3%) and homosexual (40.4%) males, and the lowest prevalence among heterosexual males (18.6%). After adjusting for confounding, bisexual/homosexual males had higher rates of perceived discrimination (IRR = 1.88, p < 0.001), recent suicidal ideation (IRR = 1.51, p = 0.008), lifetime suicide attempt (IRR = 2.09, p < 0.001) and recent depressive symptoms (IRR = 1.34, p < 0.001) than heterosexual males. Analysis of β-coefficients suggested that discrimination may mediate a small to moderate proportion of the association between sexual minority status and poor mental health.

LIMITATIONS

Use of cross-sectional data.

CONCLUSION

Poor mental health is more common among sexual minority males, and discrimination may be a contributor to these mental health disparities. Reducing discrimination should be considered as part of a strategy to improve the mental wellbeing of sexual minority males.

Household air pollution and COPD: cause and effect or confounding by other aspects of poverty?

SETTING :

Household air pollution (HAP) and chronic obstructive pulmonary disease (COPD) are both major public health problems, reported to cause around 4 million and 3 million deaths every year, respectively. The great majority of these deaths, as well as the burden of disease during life is felt by people in low- and middle-income countries (LMICs).

OBJECTIVE AND DESIGN :

The extent to which HAP causes COPD is controversial; we therefore undertook this review to offer a viewpoint on this from the Global Initiative for COPD (GOLD).

RESULTS :

We find that while COPD is well-defined in many studies on COPD and HAP, there are major limitations to the definition and measurement of HAP. It is thus difficult to disentangle HAP from other features of poverty that are themselves associated with COPD. We identify other limitations to primary research studies, including the use of cross-sectional designs that limit causal inference.

CONCLUSION :

There is substantial preventable morbidity and mortality associated with HAP, COPD and poverty, separately and together. Although it may not be possible to define clear causal links between HAP and COPD, there is a clear urgency to reduce the avoidable burden of disease these inflict on the world’s poor.

Comparative Study of Structural, Morphological, Magneto-Optical and Photo-Catalytic Properties of Magnetically Reusable Spinel MnFe₂O₄ Nano-Catalysts

Spinel MnFe2O4 nanostructures were synthesized by simple, economical and eco-friendly microwave combustion (MCM) and conventional combustion (CCM) methods using metal nitrates and glycine used as the fuel, instead of toxic inorganic/organic catalyst, template and surfactant. Powder XRD and FT-IR, EDX and SAED results were confirmed the products have a cubic phase spinel structure. EDX and SAED results confirmed purity and high crystallinity without any other secondary phase impurities. HR-SEM and HR-TEM analysis indicate that the MCM and CCM products consist of nano- and microstructures, respectively. The optical band gap (Eg) was measured using Kubelka-Munk model and it shows higher value (2.37 eV) for MnFe2O4-MCM than MnFe2O4-CCM (2.15 eV), due to the smaller particle size of MnFe2O4-MCM. VSM results showed a superparamagnetic behavior and the magnetization (Ms) value of MnFe2O4-MCM is higher i.e., 39.68 emu/g than MnFe2O4-CCM (33.59 emu/g). It was found that the sample MnFe2O4-MCM have higher surface area than MnFe2O4-CCM, which in turn leads to the improved performance towards the photocatalytic degradation (PCD) of methylene blue (MB) and it was found that the sample MnFe2O4-MCM show higher PCD efficiency (96.48%) than MnFe2O4-CCM (84.95%). Also, MnFe2O4 show higher activity with good reusability, and eco-friendly materials for industrial and technological applications.

Wilms' tumour 1 gene mutations in south Indian children with steroid-resistant nephrotic syndrome

Background & objectives:

Clinically, nephrotic syndrome (NS) is a diverse group of symptoms; about 20 per cent of NS cases are resistant to steroid treatment, and within ten years they progress to end-stage renal disease. The present study was undertaken to identify the mutations of Wilms’ tumour 1 (WT1) gene in steroid-resistant NS (SRNS) children.

Methods:

A total of 173 children with SRNS and 100 children in the control group were enrolled in the study. DNA extraction was done, screened for WT1 (exons 8 and 9) gene amplified by polymerase chain reaction and direct sequencing. Karyotype analyses were done for WT1 mutation cases.

Results:

WT1 mutations were found in three of 173 SRNS cases (2 girls, 1 boy). All of them had intron 9 (IVS 9 + 4 C>T, 2; IVS + 5 G>A, 1) mutation. Of these three cases, one had familial and another two had sporadic history. Renal histology analysis showed two cases with focal segmental glomerulosclerosis (FSGS) and they had external female genitalia but 46, XY karyotype. Both of them had streak gonads. Of the three cases, one expired.

Interpretation & conclusions:

The findings of the present study indicate that all females with SRNS-FSGS should be screened for WT1 gene mutation to diagnose whether they have FS for possible gonadectomy.

Susceptible and protective associations of HLA DRB1*/DQB1* alleles and haplotypes with ischaemic stroke

Stroke has emerged as the second commonest cause of mortality worldwide and is a major public health problem. For the first time, we present here the association of human leucocyte antigen (HLA)-DRB1*/DQB1* alleles and haplotypes with ischaemic stroke in South Indian patients. Ischaemic stroke (IS) cases and controls were genotyped for HLA-DRB1*/DQB1* alleles by polymerase chain reaction sequence-specific primers (PCR-SSP) method. The frequencies of HLA class II alleles such as DRB1*04, DRB1*07, DRB1*11, DRB1*12, DRB1*13, DQB1*02 and DQB1*07 were high in IS patients than in the age- and gender-matched controls, suggesting that the individuals with these alleles are susceptible to ischaemic stroke in South India. The frequencies of alleles such as DRB1*03, DRB1*10, DRB1*14, DQB1*04 and DQB1*05 were less in IS cases than in the controls, suggesting a protective association. Haplotypes DRB1*04-DQB1*0301, DRB1*07-DQB1*02, DRB1*07-DQB1*0301, DRB1*11-DQB1*0301 and DRB1*13-DQB1*06 were found to be high in IS patients conferring susceptibility. The frequency of haplotype DRB1*10-DQB1*05 was high in controls conferring protection. IS-LVD and gender-stratified analysis too confirmed these susceptible and protective associations. Thus, HLA-DRB1*/DQB1* alleles and haplotypes strongly predispose South Indian population to ischaemic stroke. Further studies in different populations with large sample size or the meta-analysis are needed to explain the exact mechanism of associations of HLA gene(s) with IS.

Management of tripod fractures (zygomaticomaxillary complex) 1 point and 2 point fixations: A 5-year review

The zygomaticomaxillary complex (ZMC) plays a key role in the structure, function, and esthetic appearance of the facial skeleton. They can account for approximately 40% of mid-face fractures. They are the second most common facial bone fracture after nasal bone injuries. The fracture complex results from a direct blow to the malar eminence and results in three distinct fracture components that disrupt the anchoring of the zygoma. In addition, the fracture components may result in impingement of the temporalis muscle, trismus (difficulty with mastication) and may compromise the infraorbital foramen/nerve resulting in hypesthesia within its sensory distribution. A 4-year retrospective review of all patients treated with ZMC fractures at oral and maxillofacial surgery department, sree balaji dental college and hospital was performed. Computed tomography scans were reviewed. Demographics, treatment protocols, outcomes, complications, reoperations, and length of follow-up were identified. A total of 245 patients was identified by the Current Procedural Terminology codes for ZMC fractures. Closed or open reduction methods were performed with the goal of treatment being preservation of normal facial structure, sensory function, globe position, and mastication functionality. Unacceptably poor surgical outcomes are uncommon. Significant facial asymmetry requiring surgical revision occurs in 3-4% of patients. Postoperative infection rates are extremely low, and these infections nearly always resolve with oral antibiotics. In general, the long-term prognosis after repair of ZMC fractures is very good.

Bupivacaine versus lignocaine as the choice of locall anesthetic agent for impacted third molar surgery a review

One of the most important goal in minor surgical procedures is to achieve proper and sufficient anesthesia and analgesia preoperatively, intraoperatively and in the immediate postoperative period. Several local anesthetic agents have been cited in the literature and studied. Bupivacaine is one of the most common long-acting anesthetic agents being used for surgical removal of impacted third molars. Lignocaine is one of the commonest short-acting anesthetic agents being used for the same procedure. In this review article, the analgesic and anesthetic abilities of the bupivacaine versus lignocaine have been reviewed while surgical removal of impacted third molars.

Immediate placement of endosseous implants into the extraction sockets

Implant by definition "means any object or material, such as an alloplastic substance or other tissue, which is partial or completely inserted into the body for therapeutic, diagnostic, prosthetic, or experimental purpose." The placement of a dental implant in an extraction socket at the time of extraction or explantation is known as immediate implant placement whereas delayed placement of implant signifies the implant placement in edentulous areas where healing has completed with new bone formation after the loss of tooth/teeth. Recent idea goes by "why late when it can be done immediately." There are several advantages of immediate placement of implants, and lots of studies have been done. In this article, the advantages and disadvantages of immediate versus delayed placement of implants have been reviewed.

The phosphoinositide-3-kinase (PI3K)-delta and gamma inhibitor, IPI-145 (Duvelisib), overcomes signals from the PI3K/AKT/S6 pathway and promotes apoptosis in CLL

The functional relevance of the B-cell receptor (BCR) and the evolution of protein kinases as therapeutic targets have recently shifted the paradigm for treatment of B-cell malignancies. Inhibition of p110δ with idelalisib has shown clinical activity in chronic lymphocytic leukemia (CLL). The dynamic interplay of isoforms p110δ and p110γ in leukocytes support the hypothesis that dual blockade may provide a therapeutic benefit. IPI-145, an oral inhibitor of p110δ and p110γ isoforms, sensitizes BCR-stimulated and/or stromal co-cultured primary CLL cells to apoptosis (median 20%, n=57; P<0.0001) including samples with poor prognostic markers, unmutated IgVH (n=28) and prior treatment (n=15; P<0.0001). IPI-145 potently inhibits the CD40L/IL-2/IL-10 induced proliferation of CLL cells with an IC50 in sub-nanomolar range. A corresponding dose-responsive inhibition of pAKT(Ser473) is observed with an IC50 of 0.36 nM. IPI-145 diminishes the BCR-induced chemokines CCL3 and CCL4 secretion to 17% and 37%, respectively. Pre-treatment with 1 μM IPI-145 inhibits the chemotaxis toward CXCL12; reduces pseudoemperipolesis to median 50%, inferring its ability to interfere with homing capabilities of CLL cells. BCR-activated signaling proteins AKT(Ser473), BAD(Ser112), ERK(Thr202/Tyr204) and S6(Ser235/236) are mitigated by IPI-145. Importantly, for clinical development in hematological malignancies, IPI-145 is selective to CLL B cells, sparing normal B- and T-lymphocytes.

Naturally occurring autoantibodies interfere with β-amyloid metabolism and improve cognition in a transgenic mouse model of Alzheimer's disease 24 h after single treatment

There is evidence that naturally occurring antibodies directed against Aβ (nAbs-Aβ) have a role in Aβ-metabolism and Aβ-clearance. The presence of nAbs-Aβ leads to a reduction in amyloid fibrillation and thus a reduction in their toxicity. We investigated the effects of nAbs-Aβ in respect to oligomerization and used the Tg2576 transgenic mouse model in order to investigate the rapid effect with a single-dose (24 h) on oligomer breakdown and cytokine secretion along with immunohistochemical characterization of synaptic plasticity. nAbs-Aβ were able to reduce toxic oligomer concentration with an increase in Aβ-monomers. Cytokine secretion was significantly reduced. Synaptic plasticity was also improved after administration of nAbs. Finally, single treatment lead to a significant improvement in cognition. This study demonstrates the efficacy of nAbs-Aβ and presents evidence that several hallmarks of the disease are targeted by nAbs-Aβ.

Household fuels, low birth weight, and neonatal death in India: the separate impacts of biomass, kerosene, and coal

We examined the impact of maternal use of different household cooking fuels in India on low birth weight (LBW<2500g), and neonatal mortality (death within 28 days of birth). Using cross-sectional data from India's National Family Health Survey (NFHS-3), we separately analyzed the prevalence of these two outcomes in households utilizing three types of high-pollution fuels for cooking - biomass, coal, and kerosene - using low-pollution fuels (gas and biogas) as the comparison "control" group. Taking socioeconomic and child-specific factors into account, we employed logistic regression to examine the impact of fuel use on fetal and infant health. The results indicate that household use of high-pollution fuels is significantly associated with increased odds of LBW and neonatal death. Compared to households using cleaner fuels (in which the mean birth weight is 2901g), the primary use of coal, kerosene, and biomass fuels is associated with significant decreases in mean birth weight (of -110g for coal, -107g for kerosene, and -78g for biomass). Kerosene and biomass fuel use are also associated with increased risk of LBW (p<0.05). Results suggest that increased risk of neonatal death is strongly associated with household use of coal (OR 18.54; 95% CI: 6.31-54.45), and perhaps with kerosene (OR 2.30; 95% CI: 0.95-5.55). Biomass is associated with increased risk of neonatal death among infants born to women with no more than primary education (OR 7.56; 95% CI: 2.40-23.80). These results are consistent with a growing literature showing health impacts of household air pollution from these fuels.

Vibrational, conformational and electronic structure investigations of α,α'-dibromo-o-xylene, α,α'-dibromo-m-xylene and α,α'-dibromo-p-xylene

The Fourier transform infrared (FTIR) and FT-Raman spectra of α,α'-dibromo-o-xylene (DBOX), α,α'-dibromo-m-xylene (DBMX) and α,α'-dibromo-p-xylene (DBPX) of the configuration BrCH(2)C(6)H(4)CH(2)Br have been recorded in the range 4000-400 and 4000-100 cm(-1), respectively. The conformational analysis of these compounds was performed. The complete vibrational assignment and analysis of the fundamental modes of the most stable conformer of the compounds were carried out using the experimental FTIR and FT-Raman data, and quantum mechanical studies. The observed vibrational frequencies were compared with the wavenumbers derived theoretically for the optimized geometry of the compounds from the DFT-B3LYP gradient calculations employing the standard 6-31G**, high level 6-311++G** and cc-pVTZ basis sets. The structural parameters and vibrational wavenumbers obtained from the DFT method are in good agreement with the experimental data. The potential energy distributions of the fundamental modes were also calculated with DFT force fields utilizing Wilson's FG matrix method. The effect of -CH(2)Br group on the skeletal vibrations has been discussed.

Characterization of indoor bioaerosols from a hospital ward in a tropical setting

OBJECTIVES

Study was conducted to assess whether temporal variation exists in airborne microbial concentrations of a hospital ward (west-Chennai, India) using active and passive methods, and characterise the microorganisms.

METHODS

Air samples (duplicates) were collected simultaneously using exposed-plate, impingement (BioSampler) and filtration (personal sampling filter cassette loaded with gelatin filter) methods over different periods of the year. Bacterial plates were incubated at 37°C and observed for growth after 48h; fungal plates were incubated at 25°C and 37°C and observed upto 7 days. Microorganisms were identified using standard microbiological procedures.

RESULTS

Microbial loads were found to vary with the sampling method. Concentrations of bacteria were higher (exposed-plate: 45-150 CFU/plate; impingement: 1.12E+03-1.6856E+05 CFU/m(3); filtration: 3.788E+03-1.91111E+05 CFU/m(3)) than fungi (exposed-plate: 0-13 CFU/plate; impingement: 0-3.547E+03 CFU/m(3); filtration: 0-1.515E+04 CFU/ m(3)). Coagulase-negative Staphylococci and Micrococci were the predominant Gram-positive cocci in active and passive samples. Enterobacter and Pseudomonas were the predominant Gram-negative bacilli. Among fungi, Aspergillus niger was isolated throughout the year. There was no significant temporal variation in airborne microbial loads irrespective of methods.

CONCLUSIONS

Exposed-plate method was found to capture microorganisms efficiently with little variation in duplicate samples, suggesting its use in hospitals for preliminary assessment of indoor air quality and determine pathogenic microorganisms due to particle fall-out.

Bilateral ovarian teratoma complicated with carcinosarcoma in a 68 year old woman: a case report

Background

Composing of less than 1% of all ovarian cancers, immature teratoma is a malignancy that mainly affects the young, and they present with advanced disease. The treatment of immature teratoma is conservative primary surgery usually involving unilateral salpingo-oophorectomy followed by combination chemotherapy.

Case presentation

Here we present a case of a 68 year old woman with bilateral ovarian teratoma complicated with carcinosarcoma. The patient was diagnosed as FIGO stage IIIC. She underwent neoadjuvant chemotherapy and interval cytoreduction followed by optimal cytoreduction. The post operative management strategies and gynaecological follow up studies revealed no evidence of regional or distant metastasis.

Conclusion

Thus the choice of initial treatment should be decided in a selective fashion depending on various prognostic factors in order to increase the survival of the patients.

Structural and Optical Characterization of High-Quality Cubic GaN Epilayers Grown on GaAs and 3C-SiC Substrates by Gas-Source MBE Using RHEED In Situ Monitoring

By monitoring RHEED reconstruction patterns during gas source molecular beam epitaxy growth, the optimization of the growth for cubic GaN was carried out successfully. Cubic GaN epilayer having a X-ray diffraction width of 16min and a low temperature photoluminescence emission width of 19meV was obtained on a 3C-SiC substrate by adjusting the effective III/V ratio in-situ during the growth, which can be inferred from the surface reconstruction transitions. It was found that the surface reconstructions of cubic GaN surfaces are good indices for the optimization of growth parameters.

Surface Reconstructions and III-V Stoichiometry: The Case of Cubic and Hexagonal GaN

Surface reconstructions for MBE grown GaN are identified. Different cases are considered according to the type of substrate or crystal symmetry and surface phase diagrams are obtained. Through different examples, it is shown how growth monitoring can be efficiently achieved through the use of surface reconstructions. Finally, from the observation that a residual arsenic overpressure in the MBE chamber changes the surface reconstructions of cubic (001) GaN grown onto 3C-SiC (001) substrates to that commonly observed for GaN growth on (001) GaAs, it is proposed that arsenic might be a surfactant for nitride growth.

Fine needle aspiration cytology in the management of a parotid mass: a two centre retrospective study

OBJECTIVES

There is a diversity of opinion regarding the role of fine needle aspiration cytology (FNAC) in the pre-operative evaluation of the parotid mass. This study further investigates the role of FNAC from the standpoint of the clinician attempting to resolve one or more clinical issues.

METHODS

A retrospective study conducted at two UK Hospitals with no overlap of cytopathologists or surgeons. Patients undergoing parotidectomy at each institution were identified from Pathology department databases. The definitive histopathological diagnosis was compared with any pre-operative FNAC diagnosis. Cytology results were classified as suggestive, non-diagnostic, sampling error, or misleading.

SETTING

The study was conducted in a District General Hospital and a University Teaching Hospital providing secondary care for each community.

RESULTS

For the University Teaching Hospital the sensitivity in distinguishing malignant from benign disease was 79% (95% CI 61-97%) with a specificity 84% (95% CI 73-95%). However, three of eight patients with a primary parotid salivary gland malignancy were reported as having benign disease on FNAC. For the participating District General Hospital the sensitivity in distinguishing malignant from benign disease was 38% (95% CI 13-63%) and specificity 95% (95% CI 73-95%).

CONCLUSIONS

Fine needle aspiration cytology does not reliably distinguish a benign from a malignant primary salivary gland neoplasm in the participating institutions. Where clinical teams use FNAC in an attempt to resolve this clinical problem, the results should be interpreted with caution and an ongoing audit of performance is required.

HLA-DRB1*, -DQB1* in Piramalai Kallars and Yadhavas, two Dravidian-speaking castes of Tamil Nadu, South India

Two Dravidian-speaking castes of Tamil Nadu, Piramalai Kallars (PKs, n = 205) and Yadhavas (YDs, n = 239) and a random panel (84) were studied for HLA-DRB1* and -DQB1* polymorphisms by DNA-SSOP typing methods. XI and XII International Histocompatibility primers and non-radioactive-labelled oligo probes were employed to identify the alleles. Results revealed that PKs possessed >0.1 allele frequencies of HLA-DRB1*15011, 0301, -DQB1*0201, 0501 and 0601; YDs, HLA-DRB1*0301, 0401, 07 and -DQB1*0601; and the random panel, DRB1*15021, 0401, 07, -DQB1 0201, 0301, 0302 and 0501. The highest frequency of DRB1*1501 in the world (GF = 0.225) was found in PKs. The most frequent two-locus haplotype (>500/10,000) in all the study samples was DRB1*10-DQB1*0501, while 1501-0601 was frequent in PKs and YDs. Comparison of the HLA-DRB1* data with Eastern European and South-East Asian populations suggested migration as the prime cause of the observed diversity in DRB1* allele frequencies. Nonetheless, the heterozygocity test and Watterson's homozygosity test indicated that balancing selection still operates on HLA-DRB1* locus, in this endemic region of various infectious diseases. This and spatial autocorrelation analysis support the view that selection may be a cause of "generating" new variants and allelic diversity in different ancient settlements. The study suggested that South Indian, inbred, endogamous, sympatrically isolated castes or similar well-defined breeding isolates around the world, living under the same milieu-epidemiology, may be ideal models to test the immunogenetic basis of disease susceptibility.

Identification of Virulent Isolates of the Entomopathogenic FungusNomuraea Rileyi(F) Samson for the Management ofHelicoverpa ArmigeraandSpodoptera Litura

Eleven geographical isolates of the entomopathogenic fungus Nomuraea rileyi (Farlow) Samson of Helicoverpa armigera (Hubner)/Spodoptera litura (Fabricius) origin were studied for efficacy against the two host insects. Laboratory bioassays at a concentration of 2 x 10(8) conidia ml(-1) indicated that N. rileyi isolates of S. litura origin were better in terms of time taken for mycosis and mortality in both the test larvae: S. litura (77-80% mortality in 7 days) and H. armigera (79-85% in 8 days). Among the isolates of S. litura origin, geographical isolates from Hyderabad and Karimnagar were superior in terms of high percent kill as well as 100% germination of conidia within 48 h. Fastest germination was observed with Karimnagar isolate followed by Hyderabad isolate. Conidial yield was highest on barley-carrot extract-yeast extract medium. However in terms of material cost, barley-yeast extract medium was the lowest. The Karimnagar isolate of S. litura origin gave the highest conidial yield on barley-yeast extract medium. Chitinolytic enzyme profiles of different isolates revealed polymorphism in all the isolates from S. litura origin. Overall among the parameters studied the best traits were found in the Karimnagar isolate of S. litura origin.