Evaluation of peptone glucose fluconazole agar as a selective medium for rapid and enhanced isolation of Aspergillus fumigatus from the respiratory tract of bronchopulmonary aspergillosis patients colonized by Candida albicans.

We have reported earlier that Aspergillus fumigatus is inhibited in vitro by Candida albicans which also interferes in its isolation from sputum experimentally seeded with predetermined graded inocula of the two fungi. It was further shown that this interference was neutralized by employing peptone glucose agar with incorporation of fluconazole which is more inhibitory to C. albicans than to A. fumigatus. This communication embodies the results of evaluation of peptone glucose fluconazole agar (PGFA) as a selective culture medium for rapid and enhanced isolation of A. fumigatus from sputum of patients clinically suspected of aspergillosis with C. albicans colonization in the respiratory tract. Of the 23 sputum specimens and one broncho-alveolar lavage collected from 15 suspected aspergillosis patients, A. fumigatus was isolated from all (100%) on PGFA as against only 19 specimens (79%) that proved to be positive on the control PGA medium (P<0.05). The greater efficacy of PGFA than that of PGA was further evident from the 2-fold higher A. fumigatus mean colony count (8.2+/-1.87) on the former medium than on the latter (3.7+/-1.00), and this difference was found to be statistically significant (P<0.05). Besides, A. fumigatus colonies were macroscopically recognizable within 2-3 days on PGFA at 28 degrees C in strong contrast to 5-7 days required on PGA. Based upon these observations, PGFA is recommended for wider application as a selective medium for rapid and enhanced recovery of A. fumigatus from sputum of patients clinically suspected of aspergillosis with C. albicans colonization in their respiratory tract.     

Polydrug use (the use of drugs in combination): A brief review

This brief review provides an overview of this topic; it is not a critical review. Polydrug use is a poorly defined concept; it is taken here to mean the simultaneous use of more than one drug. Data on polydrug use is seldom systematically collected, and the use of alcohol and tobacco in combination with illegal drugs is frequently overlooked. If alcohol and tobacco are included, most users are polydrug users, since these drugs are used by most users of illegal drugs, and many people with alcohol problems also use illegal drugs. Polydrug use has increased; drug availability, cultural context and the 'normalization' of drug use are important factors. Gender and racial differences are observed in the prevalence of polydrug use. Implications for drug prevention include the importance of targeting multiple substance use rather than single substances. Aiming prevention campaigns at younger people and focusing on 'gateway' drugs might be more effective. But polydrug users are diverse, and a variety of strategies (aimed at different types of polydrug users) are necessary. Implications for treatment include the evidence of the greater difficulty that polydrug users have in quitting; they may therefore require additional help. A fuller, systematic, review is required; it is expected that this would recommend the commissioning of additional research on this poorly understood phenomenon.     

Hyperfractionation in advanced head and neck cancer.

This preliminary study was undertaken to observe tumour response and normal tissue tolerance to hyperfractionation. This study showed encouraging locoregional control rate in advanced head and neck cancer. Responses T4 tumors are poor and are prone to recur. This indicates that probably greater dose is needed to control T4 disease. We used 7920 cGy for T4 and late T3 status tumour. This dose is well tolerated by patients. Control of T4 tumours may further be increased by increasing total dose, but in view of inadequate clear cut numerical data of tissue tolerance derived by L-Q = Linear Quadratic formula which is still under clinical trial, further increase in total dose cannot be overemphasized. Longer follow up is necessary to assess the long term control rate and late tissue reaction. There is a need of randomized controlled clinical trial to compare hyperfractionation and conventional fractionation. In next phase we are undertaking randomized study of twice daily, daily and weekly fractionation in advanced head and neck cancer.     

Astrocytoma and Schwann cells in coculture

Glial fibrillary acidic protein (GFAP) is the principal intermediate filament protein found in mature astrocytes. Although the exact function of GFAP is poorly understood, it is presumed to stabilize the astrocyte’s cytoskeleton and help in maintaining cell shape. Previous studies from our laboratory have shown that when astrocytes were cocultured with primary Schwann cells (pSCs), astrocytes became hypertrophied and fibrous with intensely positive GFAP staining and segregated Schwann cells (SCs) into pockets. In order to understand the functional role of GFAP in this already established astrocyte-SC coculture model, we generated GFAP-negative cell lines from a GFAP-positive astrocytoma cell line and cocultured both the cell lines with pSCs. Our studies demonstrate that the GFAP-positive cell line put out processes toward the SCs, whereas the GFAP-negative cells did not form processes and the majority of the cells remained round. The most significant and interesting finding of this study, however, is the formation of elaborate processes by SCs when grown in coculture with the astrocytoma cells, unlike SCs cultured alone, which showed their typical bipolar spindle-shaped morphology. The extent of processes did not seem to be dependent on GFAP, since SCs cultured with both the cell lines formed similar processes. This coculture model may be useful in elucidating the factor(s) responsible for the formation of processes by SCs and can be further help in our understanding of the mechanism of morphological transformation of SCs.     

Lactobacillus acidophilus Induces a Strain-specific and Toll-Like Receptor 2–Dependent Enhancement of Intestinal Epithelial Tight Junction Barrier and Protection Against Intestinal Inflammation

Defective intestinal tight junction (TJ) barrier is an important pathogenic factor of inflammatory bowel disease. To date, no effective therapies that specifically target the intestinal TJ barrier are available. The purpose of this study was to identify probiotic bacterial species or strains that induce a rapid and sustained enhancement of intestinal TJ barrier and protect against the development of intestinal inflammation by targeting the TJ barrier. After high-throughput screening of >20 Lactobacillus and other probiotic bacterial species or strains, a specific strain of Lactobacillus acidophilus, referred to as LA1, uniquely produced a marked enhancement of the intestinal TJ barrier. LA1 attached to the apical membrane surface of intestinal epithelial cells in a Toll-like receptor (TLR)-2–dependent manner and caused a rapid increase in enterocyte TLR-2 membrane expression and TLR-2/TLR-1 and TLR-2/TLR-6 hetero-complex–dependent enhancement in intestinal TJ barrier function. Oral administration of LA1 caused a rapid enhancement in mouse intestinal TJ barrier, protected against a dextran sodium sulfate (DSS) increase in intestinal permeability, and prevented the DSS-induced colitis in a TLR-2– and intestinal TJ barrier–dependent manner. In conclusion, we report for the first time that a specific strain of LA causes a strain-specific enhancement of intestinal TJ barrier through a novel mechanism that involves the TLR-2 receptor complex and protects against the DSS-induced colitis by targeting the intestinal TJ barrier.

Intestinal epithelial tight junctions (TJs) are the apical-most junctional complexes and act as a functional and structural barrier against the paracellular permeation of harmful luminal antigens, which promote intestinal inflammation.¹ The increased intestinal permeability caused by defective intestinal epithelial TJ barrier or a leaky gut is an important pathogenic factor that contributes to the development of intestinal inflammation in inflammatory bowel disease (IBD) and other inflammatory conditions of the gut, including necrotizing enterocolitis and celiac disease.^2,3 Clinical studies in patients with IBD have found that a persistent increase in intestinal permeability after clinical remission is predictive of poor clinical outcome and early recurrence of the disease, whereas normalization of intestinal permeability correlates with a sustained long-term clinical remission.4, 5, 6 Accumulating evidence has found that a defective intestinal TJ barrier plays an important role in exacerbation and prolongation of intestinal inflammation in IBD. Currently, no effective therapies that specifically target the tightening of the intestinal TJ barrier are available.Intestinal microbiota play an important role in modulating the immune system and in the pathogenesis of intestinal inflammation.⁷ Patients with IBD have bacterial dysbiosis in the gut, characterized by a decrease in bacterial diversity and an aberrant increase in some commensal bacteria, which are an important factor in the pathogenesis of intestinal inflammation.^8,9 Normal microbial flora of the gastrointestinal tract consists both of bacteria that are known to have beneficial effects (probiotic bacteria) on intestinal homeostasis and bacteria that could potentially have detrimental effects on gut health (pathogenic bacteria).¹⁰ The modulation of intestinal microflora affects the physiologic and pathologic states in humans and animals. For example, fecal transplantation from healthy, unaffected individuals to patients with refractory Clostridium difficile colitis is curative in up to 94% of the treated patients, and transfer of stool microbiome from obese mice induces obesity in previous lean mice, whereas transfer of microbiome from lean mice preserves the lean phenotype.11, 12, 13 The beneficial effects of gut microbiota are host and bacterial species-specific.¹⁴ Although multiple studies indicate that some commensal bacteria play a beneficial role in gut homeostasis by preserving or promoting the intestinal barrier function, because of conflicting reports, it remains unclear which probiotic species cause a persistent predictable enhancement in the TJ barrier and could be used to treat intestinal inflammation by targeting the TJ barrier. For example, some studies suggest that Lactobacillus acidophilus, Lactobacillus casei, Lactobacillus plantarum, or Lactobacillus rhamnosus cause a modest enhancement in the intestinal epithelial TJ barrier, whereas others have found minimal or no effect of these probiotic species on the intestinal TJ barrier.15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25 The major aim the current study was to perform a high-throughput screening of Lactobacillus and other bacterial species to identify probiotic species that induce a rapid, predictable, and marked increase in the intestinal epithelial TJ barrier and protect against the development of intestinal inflammation by preserving the intestinal TJ barrier.In the studies described herein, most of the probiotic species tested (>20 species or strains) had a modest or minimal effect on intestinal TJ barrier function. L. acidophilus uniquely caused a rapid and marked increase in intestinal TJ barrier function. Further analysis indicated that the effect of L. acidophilus was strain-specific, limited to a specific strain of L. acidophilus, and did not extend to other L. acidophilus strains. The L. acidophilus enhancement of the intestinal TJ barrier was mediated by live bacterial-enterocyte interaction that involved Toll-like receptor (TLR)-2 heterodimeric complexes on the apical membrane surface of intestinal epithelial cells. Our animal studies also found that L. acidophilus causes a marked enhancement in mouse intestinal barrier function and protects against the dextran sodium sulfate (DSS)–induced colitis by preserving and augmenting the mouse intestinal barrier function in a strain-specific manner.     

Incidence of Mallophaga on poultry in Dehradun (India).

The order of abundance of different mallophagan species on poultry birds in Dehradun (India) has been found to be Menopon gallinae greater than Menacanthus cornutus greater than Menacanthus stramineus greater than Goniocotes gallinae greater than Goniodes dissimilis greater than Lipeurus caponis greater than Lipeurus lawrensis tropicalis greater than Goniodes gigas. The intensity of these species upon 1249 birds has been recorded by coding system. The correlation between the monthly incidence of different species and environmental temperature as well as R.H. has been recorded. The degree of association between four most commonly occurring combinations has also been analysed.     

Anti-microbial active composite nanoparticles with magnetic core and photocatalytic shell: TiO2-NiFe2O4 biomaterial system

Reverse micelle and chemical hydrolysis techniques have been successfully combined to synthesize composite nanoparticles consisting of a photocatalytic shell of titania and a magnetic core of nickel ferrite. The nature of titania shell, i.e. anatase or brookite, depends on the TiO₂ and NiFe₂O₄ molar ratio. The work presented here describes the photocatalytic and anti-microbial activity of the composite nanoparticles together with the magnetic characteristics of the nickel ferrite core. The TiO₂-coated NiFe₂O₄ nanoparticles retain the magnetic characteristics of uncoated nanocrystalline nickel ferrites (superparamagnetism; absence of hysteresis, remanence and coercivity at 300 K) encouraging their application as removable anti-microbial photocatalyst nanoparticles that can be extracted from the sprayed surface (human body or environment) after exposure.