Isolation, purification and characterization of an antifungal molecule produced by Bacillus licheniformis BC98, and its effect on phytopathogen Magnaporthe grisea

AIMS

Isolation of bacterial antagonist for use in the biological control of phytopathogenic fungi like rice blast fungus, Magnaporthe grisea, and to further purify and characterize the antifungal molecule produced by the antagonist.

METHODS AND RESULTS

Bacterial antagonist exhibiting highest antifungal activity against the rice blast fungus M. grisea was isolated from soil and identified as Bacillus licheniformis BC98. Besides M. grisea, the isolate also inhibited the growth of other phytopathogens such as Curvularia lunata and Rhizoctonia bataticola. Biologically active fractions were isolated from the culture filtrate and further fractionated by reverse-phase high-performance liquid chromatography (HPLC) enabling detailed structural characterization of a component of molecular mass 1035 Da. The active peptide was identified as surfactin after 500 MHz (1)H NMR analysis. Microscopic analysis of the effect of the antagonist on M. grisea revealed bulbous hyphae showing patchy and vacuolated cytoplasm when observed under the electron microscope.

CONCLUSIONS

The antagonistic lipopeptide secreted by B. licheniformis BC98 and identified as surfactin, induced morphological changes in M. grisea, inhibiting its further growth, and thus exhibiting fungicidal activity.

SIGNIFICANCE AND IMPACT OF THE STUDY

The antagonist inhibits germination of M. grisea, a potent rice phytopathogen, and therefore appears to be a potential candidate for control of rice blast disease.

LabVIEW Graphical User Interface for a New High Sensitivity, High Resolution Micro-Angio-Fluoroscopic and ROI-CBCT System

A graphical user interface based on LabVIEW software was developed to enable clinical evaluation of a new High-Sensitivity Micro-Angio-Fluoroscopic (HSMAF) system for real-time acquisition, display and rapid frame transfer of high-resolution region-of-interest images. The HSMAF detector consists of a CsI(Tl) phosphor, a light image intensifier (LII), and a fiber-optic taper coupled to a progressive scan, frame-transfer, charged-coupled device (CCD) camera which provides real-time 12 bit, 1k × 1k images capable of greater than 10 lp/mm resolution. Images can be captured in continuous or triggered mode, and the camera can be programmed by a computer using Camera Link serial communication. A graphical user interface was developed to control the camera modes such as gain and pixel binning as well as to acquire, store, display, and process the images. The program, written in LabVIEW, has the following capabilities: camera initialization, synchronized image acquisition with the x-ray pulses, roadmap and digital subtraction angiography acquisition (DSA), flat field correction, brightness and contrast control, last frame hold in fluoroscopy, looped playback of the acquired images in angiography, recursive temporal filtering and LII gain control. Frame rates can be up to 30 fps in full-resolution mode. The user friendly implementation of the interface along with the high framerate acquisition and display for this unique high-resolution detector should provide angiographers and interventionalists with a new capability for visualizing details of small vessels and endovascular devices such as stents and hence enable more accurate diagnoses and image guided interventions. (Support: NIH Grants R01NS43924, R01EB002873).

Implementation of a high-sensitivity Micro-Angiographic Fluoroscope (HS-MAF) for in-vivo endovascular image guided interventions (EIGI) and region-of-interest computed tomography (ROI-CT)

New advances in catheter technology and remote actuation for minimally invasive procedures are continuously increasing the demand for better x-ray imaging technology. The new x-ray high-sensitivity Micro-Angiographic Fluoroscope (HS-MAF) detector offers high resolution and real-time image-guided capabilities which are unique when compared with commercially available detectors. This detector consists of a 300 μm CsI input phosphor coupled to a dual stage GEN2 micro-channel plate light image intensifier (LII), followed by minifying fiber-optic taper coupled to a CCD chip. The HS-MAF detector image array is 1024×1024 pixels, with a 12 bit depth capable of imaging at 30 frames per second. The detector has a round field of view with 4 cm diameter and 35 microns pixels. The LII has a large variable gain which allows usage of the detector at very low exposures characteristic of fluoroscopic ranges while maintaining very good image quality. The custom acquisition program allows real-time image display and data storage. We designed a set of in-vivo experimental interventions in which placement of specially designed endovascular stents were evaluated with the new detector and with a standard x-ray image intensifier (XII). Capabilities such fluoroscopy, angiography and ROI-CT reconstruction using rotational angiography data were implemented and verified. The images obtained during interventions under radiographic control with the HS-MAF detector were superior to those with the XII. In general, the device feature markers, the device structures, and the vessel geometry were better identified with the new detector. High-resolution detectors such as HS-MAF can vastly improve the accuracy of localization and tracking of devices such stents or catheters.

Detecting common mental disorders in primary care in India: a comparison of five screening questionnaires

BACKGROUND

Screening of patients for common mental disorders (CMDs) is needed in primary-care management programmes. This study aimed to compare the screening properties of five widely used questionnaires.

METHOD

Adult attenders in five primary-care settings in India were recruited through systematic sampling. Four questionnaires were administered, in pairs, in random order to participants: the General Health Questionnaire (GHQ, 12 items); the Primary Health Questionnaire (PHQ, nine items); the Kessler Psychological Distress Scale (K10, 10 items), and from which we could extract the score of the shorter 6-item K6; and the Self-Reporting Questionnaire (SRQ, 20 items). All participants were interviewed with a structured lay diagnostic interview, the Revised Clinical Interview Schedule (CIS-R).

RESULTS

Complete data were available for 598 participants (participation rate 99.3%). All five questionnaires showed moderate to high discriminating ability; the GHQ and SRQ showed the best results. All five showed moderate to high degrees of correlation with one another, the poorest being between the two shortest questionnaires, K6 and PHQ. All five had relatively good internal consistency. However, the positive predictive value (PPV) of the questionnaires compared with the diagnostic interview ranged from 51% to 77% at the optimal cut-off scores.

CONCLUSIONS

There is little difference in the ability of these questionnaires to identify cases accurately, but none showed high PPVs without a considerable compromise on sensitivity. Hence, the choice of an optimum cut-off score that yields the best balance between sensitivity and PPV may need to be tailored to individual settings, with a higher cut-off being recommended in resource-limited primary-care settings.

Adult cutaneous myofibroma

A 63-year-old male presented with an asymptomatic, slow-growing swelling on the right lower limb for the past one and half years. The histopathology revealed a lobular neoplasm with a biphasic pattern of spindle shaped cells and hemangiopericytoma like areas at the periphery of the lobule. The diagnosis of adult cutaneous myofibroma was made. This case highlights the importance of histopathology in reaching a definitive diagnosis.

Biomedical informatics in the desert--a new and unique program at Arizona State University

OBJECTIVES

A new academic Biomedical Informatics (BMI) Program in Phoenix, Arizona, embodies a unique organizational structure to draw on the strengths of a computer science and informatics school and the biomedical and clinical strengths of a college of medicine, in an effort to infuse informatics approaches broadly.

METHODS

The program reflects a partnership of two state universities that situates the Arizona State University (ASU) Department of BMI on a new downtown Phoenix Biomedical Campus with the University of Arizona (UA) College of Medicine in partnership with ASU (COM-PHX). Plans call for development of faculty and expertise in the four major subdomains of BMI, as well as in various cross-cutting capabilities.

RESULTS

Coming into existence in a state that is investing significantly in biomedical science and technology, BMI has already developed Masters and PhD degree programs, is working with COM-PHX to integrate informatics intensively into the education of the medical students, and has been authorized to plan for an undergraduate program in BMI. Reflecting the statewide emphasis on the biomedical and health sector, the growing faculty are engaged in a number of research partnerships and collaborative centers.

CONCLUSIONS

As one of the newest academic BMI programs is taking shape in Arizona, it is embarking on a wide-ranging educational program and a broad research agenda that are now in their earliest stages.

Spousal sexual violence and poverty are risk factors for sexually transmitted infections in women: a longitudinal study of women in Goa, India

OBJECTIVES

To describe factors associated with incident sexually transmitted infections (STI) in a population-based sample of women in Goa, India.

METHODS

A random sample of women aged 18-45 years was enrolled in Goa from November 2001 to May 2003. All subjects who consented to participate and completed the recruitment procedure were interviewed six and 12 months after recruitment. Incident chlamydia, gonorrhoea or trichomoniasis from vaginal and/or urine specimens were detected using a commercial polymerase chain reaction and the InPouch TV Culture Kit.

RESULTS

Of the 2180 women followed up, 64 had an incident STI (incidence of 1.8% in the first six months, and 1.4% in the second six months). Incident STI was associated with low socioeconomic status, marital status, and with concurrent bacterial vaginosis. Incidence was highest among women who were married and exposed to sexual violence (10.9%), were concerned about their husbands' affairs (10.5%), or were separated, divorced or widowed women (11.0%).

CONCLUSIONS

Socially disadvantaged women are at increased risk of STI in this population. Sexual intercourse outside marriage was rarely reported in this population, and women are at risk of becoming infected within marriage, especially those with sexual violence. This highlights the vulnerabilities of socially disadvantaged married women in India, and the need for healthcare professionals to screen STI patients for violence, and provide the necessary support. The results also stress the importance of effectively diagnosing and treating married men with STI and promoting safer sex within marriage.

Scale up services for mental disorders: a call for action

We call for the global health community, governments, donors, multilateral agencies, and other mental health stakeholders, such as professional bodies and consumer groups, to scale up the coverage of services for mental disorders in all countries, but especially in low-income and middle-income countries. We argue that a basic, evidence-based package of services for core mental disorders should be scaled up, and that protection of the human rights of people with mental disorders and their families should be strengthened. Three questions are critical to the scaling-up process. What resources are needed? How can progress towards these goals be monitored? What should be the priorities for mental health research? To address these questions, we first estimated that the amount needed to provide services on the necessary scale would be US$2 per person per year in low-income countries and $3-4 in lower middle-income countries, which is modest compared with the requirements for scaling-up of services for other major contributors to the global burden of disease. Second, we identified a series of core and secondary indicators to track the progress that countries make toward achievement of mental health goals; many of these indicators are already routinely monitored in many countries. Third, we did a priority-setting exercise to identify gaps in the evidence base in global mental health for four categories of mental disorders. We show that funding should be given to research that develops and assesses interventions that can be delivered by people who are not mental health professionals, and that assesses how health systems can scale up such interventions across all routine-care settings. We discuss strategies to overcome the five main barriers to scaling-up of services for mental disorders; one major strategy will be sustained advocacy by diverse stakeholders, especially to target multilateral agencies, donors, and governments. This Series has provided the evidence for advocacy. Now we need political will and solidarity, above all from the global health community, to translate this evidence into action. The time to act is now.

Beyond race: The impact of ethnicity on the treatment outcome of locally advanced head and neck cancer

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Background: Self identified racial groups share an unequal burden of head and neck cancer . Recent evidence suggests that outcome among races is different and the causes are multifactorial. Nonetheless, differences among ethnic groups have not been reported. Herein, we decided to analyze differences in treatment response and outcome among our white and Hispanic patient population treated for locally advanced head and neck cancer. Methods: Patients were identified using the tumor registry. We reviewed retrospectively the data from medical records. 100 white Hispanics (WH) and 50 white non-Hispanics (WNH) diagnosed with locally advanced head and neck cancer and treated at our institution from 2004 to 2005, were eligible for the study. Standard statistical analysis, including Kaplan-Meier survival curve and Cox proportional hazard models were used. P value of <0.05 was considered for statistical significance. Results: Preliminary results reveal that, in our study population, median age at diagnosis, gender, performance status (ECOG 0–2) and squamous cell histology did not differ significantly between the two groups. Stage 4 at diagnosis was more commonly observed in Hispanics as opposed to WNH (85.7% vs 68.6%) (P = 0.1). Surgery was more commonly used as an initial treatment option in Hispanics than WNH (42.8% vs 28.6%) (P = 0.18) while chemotherapy was less likely to be used (78.6% vs. 91.4%) (P = 0.15). Hispanics were more likely to smoke than WNH (P = 0.0003) and were equally exposed to chronic alcohol use. Patients from the Hispanic group were more likely to respond to therapy than whites by Chi-squared analysis but this difference was not statistically significant (P = 0.09). No differences were seen in disease free survival. Kaplan-Meier estimate of median overall survival was 16 months for Hispanics vs. 25 months for whites but this difference did not reach statistical significance (P = 0.26). Final analysis will be available at the time of the annual meeting. Conclusion: In our experience, a trend for decrease overall survival was noted in the Hispanic ethnic group. This may be in part due to more advanced stage at presentation. Nonetheless, in order to definitively answer this question, further research is warranted.

No significant financial relationships to disclose.