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1.
BACKGROUND: Lymphatic filariasis is a major public health problem in tropical countries. Earlier reports have reported microfilariae as an incidental finding in body fluids and fine needle aspiration smears from various sites. CASES: The findings of body fluid cytology and fine needle aspiration smears from six patients with microfilariae in association with other conditions--tubercular pleural effusion/lymphadenitis, pregnancy and non-Hodgkin's lymphoma--are presented. Three patients demonstrated an associated eosinophilic cellular exudate. Adherence of inflammatory cells to microfilariae was seen in two patients. CONCLUSION: Although microfilariae in cytologic smears are considered incidental findings, the association of microfilariae with debilitating conditions suggests that it is an opportunistic infection and needs further study.  相似文献   
2.
This study was conducted to examine the relationship between the concentration of zinc and neutral α-glucosidase (NAG) with semen quality. Semen samples from 75 male partners of couples who were attending the Obstetrics and Gynecology Department were analyzed for semen quality. Based on sperm count, the subjects were divided into three groups. Zinc and neutral α-glucosidase activity were estimated in seminal plasma. Results showed that mean the α-glucosidase activity was lowest among the azoospermic group with respect to oligozoospermic and normozoospermic groups. Mean zinc levels were also lower among azoospermics compared to oligozoospermic and normospermic groups. The difference was statistically significant (p<0.05). A significant positive correlation was observed between zinc levels and sperm count (r=0.29, p<0.05) and zinc and α-glucosidase activity (r=0.31, p<0.05) in seminal plasma. These results suggest that zinc and neutral α-glucosidase seem to play an important role in human reproduction.  相似文献   
3.
Here we describe the biosynthesis and characterization of fluorinated protein block polymers comprised of the two self-assembling domains (SADs): elastin (E) and the coiled-coil region of cartilage oligomeric matrix proteins (C). Fluorination is achieved by residue-specific incorporation of p-fluorophenylalanine (pFF) to create pFF-EC, pFF-CE, and pFF-ECE. Global fluorination results in downstream effects on the temperature-dependent secondary structure, supramolecular assembly, and bulk mechanical properties. The impact of fluorination on material properties also differs depending on the orientation of the block configurations as well as the number of domains in the fusion. These studies suggest that integration of fluorinated amino acids within protein materials can be employed to tune the material properties, especially mechanical integrity.  相似文献   
4.
The nonspecific ability of anaerobic sludge bacteria obtained from cattle dung slurry was investigated for 17 different dyes in a batch assay system using sealed serum vials. Experiments using Reactive Violet 5 (RV 5) showed that sludge bacteria could effectively decolorize solutions having dye concentrations up to 1000 mg l−1 with a decolorization efficiency of above 75% during 48 h of incubation. Headspace gas composition of anaerobic batch systems for varying dye concentration revealed that lower concentrations of RV 5 (upto 500 mg l−1) were found to be stimulatory to the methanogenic activity of sludge bacteria. However at higher dye concentrations, the headspace gas composition was found to be similar to batch assay controls without dye, indicating that dye at higher concentrations was inhibitory to methanogenic bacteria of sludge. The optimum inoculum and incubation temperature for maximum decolorization of RV 5 was found to be 9.0 g l−1(in terms of total solids) and 37°C, respectively. Of sixteen other dyes tested, nine (Reactive Black 5, Reactive Blue 31, Reactive Blue 28, Reactive Red HE8B, Reactive Yellow, Reactive Golden Yellow, Mordant Orange, Novatic Olive R S/D & Navilan Yellow GL) were decolorized with more than 88% efficiency; three (Orange II, Navy Blue HER & Novatic Blue BC S/D) were decolorized with about 50–65% efficiency, whereas other three dyes (Procion Orange H2R, Procion Brilliant Blue HGR & Novatic Blue BC S/D) were decolorized with less than 40% efficiency. Though Ranocid Fast Blue was decolorized with about 92.5% efficiency, this was merely due to sorption, whereas the other dyes were decolorized due to biotransformation.  相似文献   
5.
Asthma is epidemic in developed and developing countries including those in the Caribbean where it is widely believed that African dust, transported in high concentrations in the Trade Winds every year, is a major causative factor. The link between asthma and dust in the Caribbean is based largely on anecdotal evidence that associates sharp increases in the occurrence of asthma symptoms with hazy conditions often caused by dust. Here we report on a 2-year study of the relationship between the daily concentrations of dust measured in on-shore Trade Winds at Barbados and pediatric asthma attendance rates at Queen Elizabeth Hospital (QEH). We looked for large increases in QEH daily attendances in relation to daily dust concentrations as previously suggested by anecdotal observations. We could not find any obvious relationship although there may be more subtle linkages between dust and asthma. Our measurements show, however, that the concentration of dust in the size range under 2.5 μm diameter is sufficiently high as to challenge United States Environmental Protection Agency air quality standards for respirable particles. Thus, African dust may constitute a health threat of a different nature, producing symptoms less obvious than those of asthma.  相似文献   
6.
Microbes are known to interact and communicate with their neighbouring cells by releasing diverse types of low molecular weight diffusible metabolites. This paper describes the identification of iturins, fengycins and surfactins secreted by Bacillus tequilensis P15 isolated from sea coast of Jakhao, Kutch, India, using liquid chromatography coupled electron spray ionization tandem mass spectrometry. In methanol soluble fraction of acid precipitate harvested from cell free supernatant of B. tequilensis P15, 5 variants of iturins, 6 of fengycins and 39 surfactins could be identified. In particular, new surfactins with Ile/Leu at position 5 and Asp at position 6 in the peptide chain were discovered, which have not been previously reported. A novel class of novel surfactin consisting of Glu/methyl ester of Asp at position 5 in peptide chain was also identified. In addition, several linear forms of surfactins were also identified in the methanol soluble extracellular fraction of B. tequilensis P15. This is the first report on co-production of all the three classes of cyclic lipopeptides by a marine isolate B. tequilensis.  相似文献   
7.
Dental implants have to be placed with the long axis in different angulations due to the change in bone morphology. The objective of this study was to investigate the different bone remodeling response induced by the tilted dental implants and to assess whether it could lead to bone loss and implant failure. In this study, bone remodeling due to palato-labially inclined dental implants placed in the anterior maxillary incisor region was simulated. CT-based finite element models of a maxillary bone with dental implants were created herein. Five dental implants were placed at \(+10^{\circ }\), \(+5^{\circ }\), \(0^{\circ }\), \(-5^{\circ }\) and \(-10^{\circ }\), respectively. The remodeling progression was recorded and compared. Model \(-10^{\circ }\) (palatal side) shows the highest bone density values, but the inclined implant at \(+10^{\circ }\) (labial side) leads to significant bone loss. From a biomechanical perspective, it is speculated that a palatally inclined implant is more likely to enhance the bone density in the maxillary anterior region, but labial inclination of implant could jeopardize its stability.  相似文献   
8.
Uniform and monodispersed silica nanoparticles were synthesized with a mean diameter of 100 ± 20 nm as analyzed by Transmission Electron Microscopy (TEM). Glutaraldehyde was used as a coupling agent for efficient binding of the lipase onto the silica nanoparticles. For the hydrolysis of pNPP at pH 7.2, the activation energy within 25–40 °C for free and immobilized lipase was 7.8 and 1.25 KJ/mol, respectively. The Vmax and Km of immobilized lipase at 25 °C for pNPP hydrolysis were found to be 212 μmol/min/mg and 0.3 mM, whereas those for free lipase were 26.17 μmol/min and 1.427 mM, respectively. The lower activation energy of immobilized lipase in comparison to free lipase suggests a change in conformation of the enzyme leading to a requirement for lower energy on the surface of the nanoparticles. A better yield (7 fold higher) of ethyl isovalerate was observed using lipase immobilized onto silica nanoparticles in comparison to free lipase.  相似文献   
9.
Synthetic dyes are extensively used in wide range of industries amongst which textile processing industries are the major consumers. Large amounts of dyes are lost in wastewaters of these industries during dyeing and subsequent washing steps of textiles. These dyes are resistant to de gradation by conventional wastewater treatment plants and are released into environment untreated thus causing pollution of surface and ground waters in the areas of the world harboring such industries. Presence of color in wastewaters has become major environmental concern and stringent discharge standards are being enforced on release of colored wastewaters in environment. The seriousness of the problem is apparent from the magnitude of the research done in this field in last decade. Increasing number of microorganisms are being described for their ability to decolorize and degrade artificial dyes and novel bioremediation approaches for treatment dye bearing wastewaters are being worked out. In this review we have investigated potential microbial processes for developing feasible remediation technology to combat environmental pollution due to dye bearing wastewaters.  相似文献   
10.

Aims

To characterize fungal antagonistic bacilli isolated from aerial roots of banyan tree and identify the metabolites responsible for their antifungal activity.

Methods and Results

Seven gram positive, endospore‐forming, rod‐shaped endophytic bacterial strains exhibiting a broad‐spectrum antifungal activity were isolated from the surface‐sterilized aerial roots of banyan tree. The isolates designated as K1, A2, A4 and A12 were identified as Bacillus subtilis, whereas isolates A11 and A13 were identified as Bacillus amyloliquefaciens using Biolog Microbial Identification System. The antifungal lipopeptides, surfactins, iturins and fengycins with masses varying in the range from m/z 900 to m/z 1550 could be detected using intact‐cell MALDI‐TOF mass spectrometry (ICMS). On the basis of mass spectral and carbon source utilization profile, all seven endophytes could be distinguished from each other. Furthermore, ICMS analysis revealed higher extent of heterogeneity among iturins and fengycins produced by B. subtilis K1, correlating well with its higher antifungal activity in comparison with other isolates.

Conclusion

Seven fungal antagonistic bacilli were isolated from aerial roots of banyan tree, exhibiting broad spectrum of antifungal activity, among which B. subtilis K1 isolate was found to be most potent. The ICMS analysis revealed that all these isolates produced cyclic lipopeptides belonging to surfactin, iturin and fengycin families and exhibited varying degree of heterogeneity.

Significance and Impact of the study

The endophytes are considered as a potential source of novel bioactive metabolites, and this study describes the potent fungal antagonistic bacilli from aerial roots of banyan tree. The isolates described in this study have a prospective application as biocontrol agents. Also ICMS analysis described in this study for characterization of antifungal metabolites produced by banyan endophytic bacilli may be used as a high throughput tool for screening of microbes producing novel cyclic lipopeptides.  相似文献   
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