Characterization of 13 newly isolated strains of anaerobic, cellulolytic, thermophilic bacteria

Characteristics of 13 newly isolated thermophilic, anaerobic, and cellulolytic strains were compared with previously described strains of Clostridium thermocellum: ATCC 27405 and JW20 (ATCC 31549). Colony morphology, antibiotic sensitivity, fermentation end-products, and cellulose degradation were documented. All 13 strains were sensitive to erythromycin (5 μg/ml) and chloramphenicol (25 μg/ml), and all strains but one were sensitive to kanamycin (20 μg/ml). Polymerase chain reaction (PCR) amplification using primers based on gene sequences from C. thermocellum ATCC 27405 was successful for all 13 strains in the case of the hydrogenase gene and 11 strains in the case of phosphotransacetylase/acetate kinase genes. Ten strains amplified a product of the expected size with primers developed to be specific for C. thermocellum 16SrRNA primers. Two of the 13 strains did not amplify any product with the PCR primers designed for the phosphotransacetylase/acetate kinase and 16SrRNA primers. A MboI-like GATC- recognizing restriction activity was present in all of the five strains examined. The results of this study have several positive implications with respect to future development of a transformation system for cellulolytic thermophiles. Journal of Industrial Microbiology & Biotechnology (2001) 27, 275–280. Received 12 September 2000/ Accepted in revised form 20 November 2000     

A simple and rapid microwave-assisted hematoxylin and eosin staining method using 1,1,1 trichloroethane as a dewaxing and a clearing agent

The use and practicability of microwave-assisted staining procedures in routine histopathology has been well established for more than 17 years. In the study reported here, we aimed to examine an alternative approach that would shorten the duration of dewaxing and clearing steps of hematoxylin and eosin (H & E) staining of paraffin sections by using a microwave oven. Although xylene is one of the most popular dewaxing and clearing agents, its flammability restricts its use in a microwave oven; thus we preferred 1,1,1 trichloroethane, which is not flammable, as the dewaxing and clearing agent in the present study. In Group I and Group II (control groups), intestine was processed with xylene and 1,1,1 trichloroethane, respectively. The sections were then stained with H & E according to the conventional staining protocol at room temperature and subdivided into two groups according to the duration of dewaxing and clearing in xylene. In Groups III and IV (experimental groups) similar tissues were processed with xylene and 1,1,1 trichloroethane, respectively; however, sections from these groups were divided into four subgroups to study the period required for dewaxing and clearing in 1,1,1 trichloroethane, then stained with H & E in the microwave oven at 360 W for 30 sec. Our conventional H & E staining procedure, which includes dewaxing, staining and clearing of sections, requires approximately 90 min, while our method using 1,1,1 trichloroethane and microwave heating required only 2 min. Our alternative method for H & E staining not only reduced the procedure time significantly, but also yielded staining quality equal or superior to those stained the conventional way. Our results suggest that 1,1,1 trichloroethane can be used effectively and safely as a dewaxing and clearing agent for H & E staining in a microwave oven.     

Evolutionary rates for tuf genes in endosymbionts of aphids

The gene encoding elongation factor Tu (tuf) in aphid endosymbionts (genus Buchnera) evolves at rates of 1.3 x 10(-10) to 2.5 x 10(-10) nonsynonymous substitutions and 3.9 x 10(-9) to 8.0 x 10(-9) synonymous substitutions per position per year. These rates, which are at present among the most reliable substitution rates for protein-coding genes of bacteria, have been obtained by calibrating the nodes in the phylogenetic tree produced from the Buchnera EF-Tu sequences using divergence times for the corresponding ancestral aphid hosts. We also present data suggesting that the rates of nonsynonymous substitutions are significantly higher in the endosymbiont lineages than in the closely related free-living bacteria Escherichia coli and Salmonella typhimurium. Synonymous substitution rates for Buchnera approximate estimated mutation rates for E. coli and S. typhimurium, as expected if synonymous changes act as neutral mutations in Buchnera. We relate the observed differences in substitution frequencies to the absence of selective codon preferences in Buchnera and to the influence of Muller's ratchet on small asexual populations.      

我国优质野生植物微孔草资源的研究与开发利用进展

微孔草是青藏高原及其邻近高海拔地区特有的野生珍贵优质油料植物资源,是获取纯天然多功能油脂成分--γ-亚麻酸(GLA)的一条新途径.微孔草油具有很高的药用、保健和营养价值,其茎叶和块根等副产品具有食用和饲用等多种用途.目前,已成为开发利用研究的重点.为此,在多年考察和试验研究的基础上,综述近年来对微孔草开发利用价值、生物学特性和资源分布等方面的研究,为开发利用微孔草资源,推动西部经济发展提供理论依据和应用技术.     

Immunotoxicity of phosphamidon following subchronic exposure in albino rats

Effect of subchronic doses of phosphamidon exposure on humoral and cell mediated immune (CMI) responses were studied in male albino rats using SRBC, ovalbumin and KLH as antigens. Humoral immune responses were assessed by estimating antibody titre against antigen and splenic plaque forming cells (PFC) assay. CMI responses were studied by using leucocyte migration inhibition (LMI), macrophage migration inhibition (MMI) and delayed type hypersensitivity (DTH) response. Results obtained in the present study revealed marked suppression of humoral and CMI responses in a dose dependent pattern. Hence, suppression of immune responses by phosphamidon even at subchronic doses is clearly an important aspect for its safety evaluation.     

PatternLab for proteomics: a tool for differential shotgun proteomics

Background  

A goal of proteomics is to distinguish between states of a biological system by identifying protein expression differences. Liu et al. demonstrated a method to perform semi-relative protein quantitation in shotgun proteomics data by correlating the number of tandem mass spectra obtained for each protein, or "spectral count", with its abundance in a mixture; however, two issues have remained open: how to normalize spectral counting data and how to efficiently pinpoint differences between profiles. Moreover, Chen et al. recently showed how to increase the number of identified proteins in shotgun proteomics by analyzing samples with different MS-compatible detergents while performing proteolytic digestion. The latter introduced new challenges as seen from the data analysis perspective, since replicate readings are not acquired.     

Melatonin treatment prevents modulation of cell-mediated immune response induced by propoxur in rats

The effect of melatonin, a major secretory product of the pineal gland, in attenuation of propoxur (2-isopropoxy phenyl N-methyl carbamate)-induced modulation of cell-mediated immune (CMI) response was studied in rats. Male Wistar albino rats were exposed to propoxur (a widely used pesticide) orally (10 mg/kg) and/or melatonin (10 mg/kg) orally for 4 weeks. CMI was measured by delayed-type hypersensitivity (DTH), leucocyte and macrophage migration inhibition (LMI and MMI) responses and estimation of cytokines TNF-alpha and IFN-gamma levels. Rats exposed to propoxur for 4 weeks showed significant decrease in DTH, LMI and MMI responses. Propoxur also suppressed TNF-alpha and IFN-gamma production significantly. Administration of melatonin alone caused a significant increase in DTH response. Although there were no changes in the LMI and MMI response, the cytokine levels were significantly increased, as compared to control. Co-administration of melatonin along with propoxur significantly nullified the effect of the pesticide on the CMI response, except DTH and reversed levels of cytokines to near control/normal values. Thus, melatonin treatment considerably attenuated immunomodulation caused by sub-chronic treatment of propoxur in experimental animals.     

Identification and characterization of a novel RF-amide peptide ligand for orphan G-protein-coupled receptor SP9155

Orphan G-protein-coupled receptors are a large class of receptors whose cognate ligands are unknown. SP9155 (also referred to as AQ27 and GPR103) is an orphan G-protein-coupled receptor originally cloned from a human brain cDNA library. SP9155 was found to be predominantly expressed in brain, heart, kidney, retina, and testis. Phylogenetic analysis shows that SP9155 shares high homology with Orexin, NPFF, and cholecystokinin (CCK) receptors, but identification of the endogenous ligand for SP9155 has not been reported. In this study, we have used a novel method to predict peptides from genome data bases. From these predicted peptides, a novel RF-amide peptide, P52 was shown to selectively activate SP9155-transfected cells. We subsequently cloned the precursor gene of the P52 ligand and characterized the activity of other possible peptides encoded by the precursor. This revealed an extended peptide, P518, which exhibited high affinity for SP9155 (EC50 = 7 nm). mRNA expression analysis revealed that the peptide P518 precursor gene is predominantly expressed in various brain regions, coronary arteries, thyroid and parathyroid glands, large intestine, colon, bladder, testes, and prostate. These results indicate the existence of a novel RF-amide neuroendocrine peptide system, and suggest that SP9155 is likely the relevant G-protein-coupled receptor for this peptide.     

Infection control and the significance of sputum and other respiratory secretions from adult patients with cystic fibrosis

Background

Although various hematologic abnormalities are seen in tuberculosis, immune thrombocytopenic purpura is a rare event.

Case Presentation

We report a case of a 29 year-old male who was presented with immune thrombocytopenia-induced hemoptysis, macroscopic hematuria and generalized petechiae. The patient was found to have clinical, microbiological and radiological evidence of active pulmonary tuberculosis. The immune thrombocytopenic purpura was successfully treated with anti-tuberculous drugs combined with corticosteroids and high dose immune globulin therapy.

Conclusion

Immune thrombocytopenic purpura can be one of the hematological manifestations of tuberculosis which has a global prevalence with increasing incidence secondary to HIV infection.