Chlamydia trachomatis infection and human papillomavirus in women with cervical neoplasia in Pernambuco-Brazil

Chlamydia trachomatis (CT) is the most common bacterial cause of sexually transmitted disease. High-risk human papillomavirus (HR-HPV) is considered the main etiological agent for cervical neoplasia. Evidences showed that the presence of co-infection of CT and HR-HPV plays a central role in the etiology of cervical intraepithelial neoplasia (CIN) and cervical cancer. The goals of this study were: evaluate the human papillomavirus (HPV) and CT prevalence among Brazilian women with abnormal cytology and provide the effect of this association on the severity of cervical neoplasia. The population of this study was composed by 142 women with incident histological incidence of CIN grades I, II, III or cervical cancer from Recife, Northeast of Brazil. The polymerase chain reaction method on a cervical brush specimen was used to detect both agents and the automatic sequencing method was used for HPV genotyping assay. The prevalence of HPV and CT was 100 and 24.65 %, respectively. Thirteen types of HPV were detected; HPV 16, 18, 31 and 33 were the most common. The most prevalent HPV types were HPV 16 and 18. A significant association between CT positive and HPV 16 infection was found (p < 0.0106; OR = 5.31; 95 % IC 1.59–17.67). In the study population, there was diversity of HPV infections, with high-risk types being the most common. Also, the data collected suggest that CT infection may play an important role in the natural history of HPV infection.     

The increased presence of repetitive motifs in the KDDR-plus recombinant protein,a kinesin-derived antigen from Leishmania infantum,improves the diagnostic performance of serological tests for human and canine visceral leishmaniasis

Visceral leishmaniasis (VL) is caused by protozoa belonging to the Leishmania donovani complex and is considered the most serious and fatal form among the different types of leishmaniasis, if not early diagnosed and treated. Among the measures of disease control stand out the management of infected dogs and the early diagnosis and appropriate treatment of human cases. Several antigens have been characterized for use in the VL diagnosis, among them are the recombinant kinesin-derived antigens from L. infantum, as rK39 and rKDDR. The main difference between these antigens is the size of the non-repetitive kinesin region and the number of repetitions of the 39 amino acid degenerate motif (6.5 and 8.5 repeats in rK39 and rKDDR, respectively). This repetitive region has a high antigenicity score. To evaluate the effect of increasing the number of repeats on diagnostic performance, we designed the rKDDR-plus antigen, containing 15.3 repeats of the 39 amino acid degenerate motif, besides the absence of the non-repetitive portion from L. infantum kinesin. Its performance was evaluated by enzyme-linked immunosorbent assay (ELISA) and rapid immunochromatographic test (ICT), and compared with the kinesin-derived antigens (rKDDR and rK39). In ELISA with human sera, all recombinant antigens had a sensitivity of 98%, whereas the specificity for rKDDR-plus, rKDDR and rK39 was 100%, 96% and 71%, respectively. When evaluated canine sera, the ELISA sensitivity was 97% for all antigens, and the specificity for rKDDR-plus, rKDDR and rK39 was 98%, 91% and 83%, respectively. Evaluation of the ICT/rKDDR-plus, using human sera, showed greater diagnostic sensitivity (90%) and specificity (100%), when compared to the IT LEISH (79% and 98%, respectively), which is based on the rK39 antigen. These results suggest that the increased presence of repetitive motifs in the rKDDR-plus protein improves the diagnostic performance of serological tests by increasing the specificity and accuracy of the diagnosis.     

The role of the daily feeding rhythm in the regulation of the day/night rhythm in triglyceride secretion in rats

Plasma triglyceride (TG) levels show a clear daily rhythm, however, thus far it is still unknown whether this rhythm results from a daily rhythm in TG production, TG uptake or both. Previous studies have shown that feeding activity affects plasma TG concentrations, but it is not clear how the daily rhythm in feeding activity affects plasma TG concentrations. In the present study, we measured plasma TG concentrations and TG secretion rates in rats at 6 Zeitgeber times to investigate whether plasma TG concentrations and TG secretion show a daily rhythm. We found that plasma TG concentrations and TG secretion show a significant day/night rhythm. Next, we removed the daily rhythm in feeding behavior by introducing a 6-meals-a-day (6M) feeding schedule to investigate whether the daily rhythm in feeding behavior is necessary to maintain the daily rhythm in TG secretion. We found that the day/night rhythm in TG secretion was abolished under 6M feeding conditions. Hepatic apolipoprotein B (ApoB) and microsomal TG transfer protein (Mttp), which are both involved in TG secretion, also lost their daily rhythmicity under 6M feeding conditions. Together, these results indicate that: (1) the daily rhythm in TG secretion contributes to the formation of a day/night rhythm in plasma TG levels and (2) a daily feeding rhythm is essential for maintaining the daily rhythm in TG secretion.     

Nucleotide sequence analysis of the lemur beta-globin gene family: evidence for major rate fluctuations in globin polypeptide evolution

Lemur beta-related globin genes have been isolated and sequenced. Orthology of prosimian and human epsilon-, gamma-, and beta-related globin genes was established by dot-matrix analysis. All of these lemur globin genes potentially encode functional beta-related globin polypeptides, though precisely when the gamma-globin gene is expressed remains unknown. The organization of the 18-kb brown lemur beta-globin gene cluster (5' epsilon-gamma-[psi eta-delta]-beta 3') is consistent with its evolution by contraction via unequal crossing-over from the putative ancestral mammalian beta-globin gene cluster (5' epsilon-gamma- eta-delta-beta 3'). The dwarf lemur nonadult globin genes are arranged as in the brown lemur. Similar levels of synonymous (silent) nucleotide substitutions and noncoding DNA sequence differences have accumulated between species in all of these genes, suggesting a uniform rate of noncoding DNA divergence throughout primate beta-globin gene clusters. These differences are comparable with those observed in the nonfunctional psi eta pseudogene and have therefore accumulated at the presumably maximal neutral rate. In contrast, nonsynonymous (replacement) nucleotide substitutions show a significant heterogeneity in distribution for both the same gene in different lineages and different genes in the same lineage. These major fluctuations in replacement but not silent substitution rates cannot be attributed to changes in mutation rate, suggesting that changes in the rate of globin polypeptide evolution in primates is not governed solely by variable mutation rates.      

Serumprotein polymorphisms in Iran

Summary The results of a population genetic investigation on Iranians are given and compared to the results obtained on other populations from Southwestern and Southern Asia. Our total material from Iran comprises n=1020 nonrelated male and female individuals of different age. The following serum groups have been typed: Hp, Gc, Gm, and Inv. In general there exist no remarkable age or sex differences in the distribution of phenotypes and alleles (the only exception: sex differences in the distribution of the Gm (7)-phenotype). The regional distribution of phenotypes and alleles yield no marked differences, too, apart from the Invphenotypes, however. For the total material of Iran the following alleles frequencies could be calculated: Hp¹=0.3045, Hp²=0.6595, Gc²=0.3405; Gm¹=0.1780, Gm^1,2=0.0537, Gm^1,5=0.0632, Gm⁵=0.7051. The Gm (7)-phenotype turned out to be 36.6%; the Inv (1)-phenotype amounts to 25.6%. Comparing with other populations, especially Pakistani and Indian samples, some heterogeneity in the distribution of phenotypes and alleles within Southwestern and Southern Asia was to be demonstrated. Some distributional trends of alleles frequencies shall be mentioned here: the increase of Hp², Gc¹, and Gm¹ alleles from West towards East, and in the opposite direction the decrease of Hp¹, Gc², and Gm⁵ alleles. Selective acting forces are supposed to be most important factors for this. D77     

Gene transfer into peanut (Arachis hypogaea L.) by Agrobacterium tumefaciens

Introduction of foreign genes into plant tissues via Agrobacterium tumefaciens based vectors requires specific knowledge of Agrobacterium-host compatibility. Therefore, to develop a transformation protocol for peanut (Arachis hypogaea L.), five Brazilian cultivars were screened with four wild-type A.tumefaciens strains. Successful transformation was dependent on specific bacterial strain-plant cultivar interactions and strain A281 was the most effective for tumor induction. Tumors displayed hormone autonomous growth, were opine positive and contained DNA that was homologous to the T-DNA of the inciting strain. Tumors induced on seed and seedling explants by A281 (pTD02) also expressed the reporter genes gus and npt-II contained in the binary vector. These results show that peanut is a permissive host for the acceptance of genes from specific A.tumefaciens gene vectors.Abbreviations GUS ß-glucuronidase (EC 3.2.1.31) - NPT-II neomycin phosphotransferase II (EC 2.7.1.95) - EDTA ethylene-diamine-tetracetic acid