High prevalence of HPV 18 and multiple infections with oncogenic HPV genotypes in women at risk of cervical cancer examined in Manaus, Brazil.

Cervical cancer is a serious public health problem in Brazil, especially in Manaus (Amazonas), the city with the highest incidence rate of cervical cancer in the country. Persistent infection with oncogenic human papillomavirus (HPV) genotypes is the cause of disease development. The aim of this study was to investigate the prevalence of oncogenic genotypes in women at high risk for cervical precancer examined in two policlinics in Manaus. One hundred and two patients who underwent colposcopy took part in the research. The DNA samples obtained from the cervical epithelium were analyzed by PCR with type-specific primers for the detection of eight oncogenic genotypes, which were chosen based on previous studies. The presence of HPV virus was detected in all samples. The most prevalent oncogenic genotypes were 18 (47.1%) and 16 (45.1%). Interestingly, HPV 18 was considered uncommon in this region. In addition to these, genotypes 31 (19.6%), 58 (19.6%), 33 (18.6%), and 45 (15.7%) also had a relatively high frequency in this population. Fifty-six women (54.9%) had multiple infections with up to five oncogenic types. Also, the presence of genotypes other than 16 and 18 was observed in most samples (57.8%), which also deserves attention since they are not covered by currently available vaccines against HPV in Brazil. The high prevalence and multiple infections with several oncogenic HPV genotypes in association with precursor lesions for cervical cancer highlighted the need to improve strategies to prevent this disease in Amazonas.

High prevalence of HPV 18 and multiple infections with oncogenic HPV genotypes in women at risk of cervical cancer examined in Manaus, Brazil

Cervical cancer is a serious public health problem in Brazil, especially in Manaus (Amazonas), the city with the highest incidence rate of cervical cancer in the country. Persistent infection with oncogenic human papillomavirus (HPV) genotypes is the cause of disease development. The aim of this study was to investigate the prevalence of oncogenic genotypes in women at high risk for cervical precancer examined in two policlinics in Manaus. One hundred and two patients who underwent colposcopy took part in the research. The DNA samples obtained from the cervical epithelium were analyzed by PCR with type-specific primers for the detection of eight oncogenic genotypes, which were chosen based on previous studies. The presence of HPV virus was detected in all samples. The most prevalent oncogenic genotypes were 18 (47.1%) and 16 (45.1%). Interestingly, HPV 18 was considered uncommon in this region. In addition to these, genotypes 31 (19.6%), 58 (19.6%), 33 (18.6%), and 45 (15.7%) also had a relatively high frequency in this population. Fifty-six women (54.9%) had multiple infections with up to five oncogenic types. Also, the presence of genotypes other than 16 and 18 was observed in most samples (57.8%), which also deserves attention since they are not covered by currently available vaccines against HPV in Brazil. The high prevalence and multiple infections with several oncogenic HPV genotypes in association with precursor lesions for cervical cancer highlighted the need to improve strategies to prevent this disease in Amazonas.

Polyandrous behavior in an overexploited giant South American turtle (Podocnemis expansa) population in Central Amazon, Brazil.

The aim of the present study was to investigate the reproductive behavior of the giant Amazon River turtle (Podocnemis expansa) in the Amazon. This was carried out by estimating the degree of polymorphism in five DNA microsatellites in a sample of 359 hatchlings from 12 nests in the Mamirauá Sustainable Development Reserve in the municipality of Tefé, state of Amazonas, Brazil. An analysis of allele frequency and variation in the five microsatellite loci allowed for determination of multiple paternity in all nests sampled. Contributions of at least four male turtles to one nest, three male turtles to six nests, and two male turtles to five nests were identified. Knowledge on the reproductive behavior of P. expansa can assist in the establishment of management and conservation strategies for the population in the Mamirauá Reserve.

Relationship between multiple paternity and reproductive parameters for Podocnemis sextuberculata (Testudines: Podocnemididae) in the Trombetas River, Brazil.

Genetic studies of multiple paternity are a valuable tool to gain information on the reproductive biology of turtles. We analyzed paternity type in Podocnemis sextuberculata and related number of fathers per nest to nesting period (beginning, middle, or end of nesting season); clutch size (number of eggs); female size; and hatchling success. Females were captured and maximum linear carapace lengths measured during the 60 days that encompass the nesting season at Rio Trombetas Biological Reserve (Pará, Brazil). Nests were marked and blood samples collected from hatchlings. Six heterologous loci were used: five from Podocnemis unifilis and one from Podocnemis expansa. Hatchlings were analyzed from 23 nests, and the rate of multiple paternity was 100%. The mean number of fathers per nest was six (± 0.9), and no significant difference between number of fathers in a nest and nesting period. Similarly there was no significant relationship between number of fathers in a nest and female size or hatchling success rate. Number of fathers was, however, positively correlated with clutch size (Spearman correlation rho = 0.47; P > 0.05). To our knowledge, this is the first study to test the relationship between multiple paternity and ecological aspects of the reproductive ecology of turtles in the genus Podocnemis.

Polyandry in the red-headed river turtle Podocnemis erythrocephala (Testudines, Podocnemididae) in the Brazilian Amazon.

The genus Podocnemis comprises six living species, including P. erythrocephala (irapuca-red-headed river turtle). Data are available concerning the reproductive biology of the species of the genus Podocnemis, but little is known about their reproductive strategies. Considering the total lack of such data for P. erythrocephala, and with the goal of contributing information on their mode of reproduction, we examined the relationships among individuals of nests of this turtle, using microsatellite markers. Using four microsatellite loci, we analyzed the progeny in six nests from two localities in the Brazilian Amazon (Santa Isabel do rio Negro and Parintins). All juveniles from each nest were analyzed. The genotypes of each juvenile from each nest were identified, and because a sample of female DNA was not available, the maternal genotype was inferred from homozygous individuals in each nest. We found that this species is promiscuous; there was multiple paternity in five of the six nests analyzed. In addition to being important for the understanding of evolutionary and genetic processes, this type of information will be useful for chelonian management projects. Our data suggest one possible difference between reproductive patterns of the different populations. This multi-paternal condition may be a natural reproductive strategy for the preservation of the genetic diversity of this species.