1H, 15N,and 13C backbone resonance assignments for the yersinia protein tyrosine phosphatase YopH

YopH is a protein tyrosine phosphatase that functions as a required virulence factor in Yersinia. Here we report the backbone resonance assignments for a point mutant of the C-terminal catalytic domain of YopH.     

Characterization of the Integration and Modular Excision of the Integrative Conjugative Element PAISt in Streptomyces turgidiscabies Car8

PAISt is a large genomic island located in the chromosome of the plant pathogen Streptomyces turgidiscabies Car8. The island carries clustered virulence genes, transfers to other Streptomyces species, and integrates by site-specific recombination at the 8 bp palindrome TTCATGAA. The palindrome is located at the 3′ end of the bacitracin resistance gene (bacA). We demonstrate that PAISt is able to excise in modules by recombination of one internal and two flanking palindromic direct repeats. The gene intSt located at the 3( end of PAISt encodes a tyrosine recombinase. Site-specific recombination activity of intSt was tested and confirmed by heterologous expression in Streptomyces coelicolor. Comparative analysis of PAISt homologues in Streptomyces scabies 87–22 and Streptomyces acidiscabies 84–104 indicates that these islands have been fixed by sequence erosion of intSt and the recombination sites.     

Epidemiology of Visceral Leishmaniasis in Georgia

This study investigated the transmission and prevalence of Leishmania parasite infection of humans in two foci of Visceral Leishmaniasis (VL) in Georgia, the well known focus in Tbilisi in the East, and in Kutaisi, a new focus in the West of the country. The seroprevalence of canine leishmaniasis was investigated in order to understand the zoonotic transmission. Blood samples of 1575 dogs (stray and pet) and 77 wild canids were tested for VL by Kalazar Detect rK39 rapid diagnostic tests. Three districts were investigated in Tbilisi and one in Kutaisi. The highest proportions of seropositive pet dogs were present in District #2 (28.1%, 82/292) and District #1 (26.9%, 24/89) in Tbilisi, compared to 17.3% (26/150) of pet dogs in Kutaisi. The percentage of seropositive stray dogs was also twice as high in Tbilisi (16.1%, n = 670) than in Kutaisi (8%, n = 50); only 2/58 wild animals screened were seropositive (2. 6%). A total of 873 Phlebotomine sand flies were collected, with 5 different species identified in Tbilisi and 3 species in Kutaisi; 2.3% of the females were positive for Leishmania parasites. The Leishmanin Skin Test (LST) was performed on 981 human subjects in VL foci in urban areas in Tbilisi and Kutaisi. A particularly high prevalence of LST positives was observed in Tbilisi District #1 (22.2%, 37.5% and 19.5% for ages 5–9, 15–24 and 25–59, respectively); lower prevalence was observed in Kutaisi (0%, 3.2% and 5.2%, respectively; P<0.05). This study shows that Tbilisi is an active focus for leishmaniasis and that the infection prevalence is very high in dogs and in humans. Although exposure is as yet not as high in Kutaisi, this is a new VL focus. The overall situation in the country is alarming and new control measures are urgently needed.     

Sister-chromatid exchanges and chromosomal aberrations in a population exposed to pesticides

Sister-chromatid exchanges (SCE) and chromosomal aberrations were studied in a population of floriculturists occupationally exposed to organophosphorus, carbamate and organochlorine pesticides. Blood samples from 36 individuals from a community of 154 persons of asiatic origin were obtained. Among the group sampled, 21 individuals exhibited at least one symptom of chronic intoxication. SCE analysis was performed in 14 symptomatic and 13 asymptomatic persons. The asymptomatic group showed a SCE frequency of 5.47 +/- 1.03 and the symptomatic group a frequency of 6.45 +/- 1.19. Comparison between both groups with the Mann-Whitney 'U' test revealed a significant difference (p 0.0409). Case-control analysis of 9 pairs matched by sex and age also showed significant differences between both groups (p 0.0104). In contrast, the frequencies of chromosomal aberrations were not correlated with intoxication symptomatology, though a significant increment of exchange-type aberrations in relation to a group of non floriculturists was observed in the population studied.     

The Condition of the Oral Mucosa at Age 70: A Population Study1

At oral examinations of 70-year old men (186) and women (199) in Göteborg (H-70-study) it was concluded that the degrees of dental invalidity and the frequencies of oral red, white and hyperplastic lesions were high in spite of the rather good physical conditions of the elderly. Variations in the general health of the subjects and their drug utilizations seemed to participate in the regulation of the threshold levels of the oral tissues against external irritations. A high percentage of the oral lesions were related to local factors, such as dental state, removable dentures, tobacco habits and factors affiliated with secretion of saliva. Insufficient functions of the dentures were found to induce hyperplastic changes even if the dentures had been worn for only a short period of time. Smoking was statistically demonstrated to be a significant contributing factor to tooth losses as well as to the induction of oral white lesions. The supervising responsibilities of the dentists are discussed on the basis of the clinical and statistical findings in this investigation.