Population genetic structure of wild and hatchery black rockfish Sebastes inermis in Korea, assessed using cross-species microsatellite markers.

The population structure of the black rockfish, Sebastes inermis (Sebastidae), was estimated using 10 microsatellite loci developed for S. schlegeli on samples of 174 individuals collected from three wild and three hatchery populations in Korea. Reduced genetic variation was detected in hatchery strains [overall number of alleles (N(A)) = 8.07; allelic richness (A(R)) = 7.37; observed heterozygosity (H(O)) = 0.641] compared with the wild samples (overall N(A) = 8.43; A(R) = 7.83; H(O) = 0.670), but the difference was not significant. Genetic differentiation among the populations was significant (overall F(ST) = 0.0237, P < 0.05). Pairwise F(ST) tests, neighbor-joining tree, and principal component analyses showed significant genetic heterogeneity among the hatchery strains and between wild and hatchery strains, but not among the wild populations, indicating high levels of gene flow along the southern coast of Korea, even though the black rockfish is a benthic, non-migratory marine species. Genetic differentiation among the hatchery strains could reflect genetic drift due to intensive breeding practices. Thus, in the interests of optimal resource management, genetic variation should be monitored and inbreeding controlled within stocks in commercial breeding programs. Information on genetic population structure based on cross-species microsatellite markers can aid in the proper management of S. inermis populations.

Persistence of passively transferred antibodies in porcine Taenia solium cysticercosis. Cysticercosis Working Group in Peru.

We evaluated the presence and persistence of anticysticercal antibodies in piglets born to Taenia solium infected sows. Infected sows from a disease-endemic area of Peru were transported to a nondisease-endemic area and impregnated. Serum samples were collected from sows and piglets on Day 2 through Week 35 after birth. Using an immunoblot specific for cysticercosis, Ig isotypes to 7 cyst antigens were measured and quantified. Serum samples from the piglets contained detectable antibodies from Week 1 through Week 35 (27 weeks after weaning). The primary Ig isotype present in both sows and piglets was IgG. Antibodies did not appear in piglet serum samples until after suckling, demonstrating that anti-cysticercal antibodies are transferred solely via colostrum. Our data have shown that maternally transferred antibodies to cyst antigens may persist through much of a pig's life. Therefore, the presence of passively transferred antibodies must be considered in studies that examine the prevalence of cysticercosis in pigs. Furthermore, when designing control strategies for cysticercosis, careful evaluation and selection of sentinel pigs becomes a crucial component of sentinel selection.

Age-specific decrease in seroprevalence of schistosomiasis in Puerto Rico.

In our previous work, we reported the first systematic, island-wide, serologic survey for schistosomiasis in Puerto Rico in 40 years. In that study, approximately 3,000 serum samples from the 76 municipalities comprising the island of Puerto Rico were tested for the detection of antibodies to S. mansoni microsomal antigens by the Falcon assay screening test-enzyme-linked immunosorbent assay (FAST-ELISA) and those positive were confirmed by an enzyme-linked immunoelectrotransfer blot (EITB). The highest EITB positivity was found in 17 municipalities, which comprised 48% of all seropositive samples. An additional finding was that 10% of the 215 EITB-positive samples were from individuals 25 years or younger and were for the most part of residents from the high seroprevalence areas. Thus, for this study we focused on 766 individuals 25 years of age or younger (45.5% males and 54.4% females), two-thirds of which were from 10 municipalities with the highest EITB seropositivity, and one-third from the 10 municipalities with the lowest EITB seropositivity found in our previous study. Of all samples, the results showed an overall FAST-ELISA positivity of 11.6%, with males similar to females (12.6 versus 10.7%, respectively). Confirmation by EITB was only 1.8%, with a males three-fold higher than females (3% versus 0.7%). When seropositivity was measured by age in five-year increments, a clear age-specific decrease in seropositivity was observed. Thus, by FAST-ELISA, 16.7% of the 21-25-year-old age group was positive, decreasing to 14.6%, 9.9%, 7.9%, and 9.3% in the 16-20-, 11-15-, 6-10-, and 1-5-year-old age groups, respectively. Confirmatory EITB showed even more impressive results: 4.7%, 2.6%, 1.2%, 0.7%, and 0% in the same age brackets. With regard to the high prevalence municipalities, only four of 10 (11 of 228 = 4.8%) had confirmatory EITB-positive samples and most were from municipalities of the Rio Grande de Loiza River basin and tributaries. The male to female positivity ratio was 4:1. Of the low prevalence municipalities, only single positive cases (by EITB) were found in three disperse municipalities. These results support the concept that there has been little transmission of S. mansoni in Puerto Rico during the first half of the 1990s and confirms anecdotal comments of local physicians who have seen virtually no new infections during the past three years. This makes the documentation of eradication of schistosomiasis from Puerto Rico feasible, a goal that should be set as being before the 100th anniversary of its discovery on the island by Isaac Gonzalez-Martinez in 1904.

[Epidemiology of preeclampsia-eclampsia at the General Hospital O'Horán. (Epidemiology of preeclampsia-eclampsia of a sample, in Yucatan)]. / Epidemiología de la preeclampsia-eclampsia en el Hospital General O'Horán. (Epidemiología de la preeclampsia-eclampsia de una muestra, en Yucatán).

The objective was to describe the epidemiology of preeclampsia-eclampsia (P-E) at the Hospital General O'Horán (HGOH) in Mérida, Yucatán, México, from 1995 to 1998. Patients with a discharge diagnosis of P-E were included. Their demographic and clinical data were ascertained. To analyze information, descriptive statistics were used. There were 143 patients. Preeclampsia was documented in 41% and eclampsia in 59%. The mean age of the group was 24.4 +/- 7.3 years. It was found that 76% came from rural area. In 79% schooling was no more than elementary education. Seventy five per cent were married. Sexual life began at a mean age of 18.8 +/- 4.3 years. There was no prenatal care in 27% of the cases. Fifty five per cent were primigravida and 43% multigravida. Nuliparity was documented in 52%. Two o more parities were documented in 48%. Complications were seen in 30%. Overall mortality rate was 5%, more frequent eclamptic patients. At the HGOH, P-E was frequently documented in women with both low socioeconomic status and fewer years of schooling. Prenatal care was also irregular. Clinical evolution was satisfactory in most of them, and the mortality rate was low, although it usually occurred in young eclamptic women.

Neurocysticercosis in persons with epilepsy in Medellín, Colombia. The Neuroepidemiological Research Group of Antioquia.

PURPOSE: A prospective series of 643 persons with epilepsy attending a reference neurologic center in Medellín, Colombia, was examined by computed tomography (CT scan) or serology or both with the enzyme-linked immunoelectrotransfer blot assay (EITB) to assess the prevalence of Taenia solium cysticercosis. METHODS: All presenting patients were consecutively enrolled in the study. Five hundred forty-six persons underwent cerebral CT scans; 376 of them also had serum EITB performed. RESULTS: Prevalence of neurocysticercosis by CT scan was 13.92%. Overall prevalence of T. solium antibodies with EITB was 9.82%, but for those with late-onset epilepsy (onset after age 30 years), prevalence increased to 17.5% and 19% for those who originated from outside urban Medellín. Seroprevalence in individuals with mixed lesions (cysts and calcifications) was 88.2% and 64.10% in those with live cysts. Conversely, only 2.72% of persons with CT findings not related to neurocysticercosis had positive EITB tests. CONCLUSIONS: Our study shows that an important proportion of individuals with epilepsy have radiologic or serologic evidence of T. solium infection, suggesting that neurocysticercosis is an important etiology for epilepsy in Colombia.

Application of the enzyme-linked immunoelectrotransfer blot to filter paper blood spots to estimate seroprevalence of cysticercosis in Bolivia.

An enzyme-linked immunoelectrotransfer blot (EITB) assay was used to study the prevalence of cysticercosis in rural Bolivia. Dried blood spots on filter paper from fingersticks were used as assay samples. Before the serosurvey, experiments were performed to show that samples eluted from dried whole blood on filter paper exhibited no decrease in sensitivity when compared with the more traditional serum samples used in the EITB. Fingerstick blood dried on filter paper is a convenient, economical way of transporting and storing field samples for epidemiologic surveys of cysticercosis in developing countries. This report shows the utility of this sample collection method in underdeveloped countries where refrigeration is not possible and where venipuncture is a problem. Blood was obtained from randomly selected residents in three rural regions of Bolivia: Chuquisaca (n = 1,859), Cochabamba (n = 1,516), and Tarija (n = 1,010). The estimated seroprevalence on 10% of the sample collected for the three regions were 9%, 4.5%, and 2%, respectively.

Geographic clustering and seroprevalence of schistosomiasis in Puerto Rico (1995).

A systematic, island-wide survey for schistosomiasis in Puerto Rico has not been conducted for more than 40 years. In 1974, a thorough survey of Boqueron de Las Piedras, a small community, showed a prevalence of 40%. No additional information on prevalence in Puerto Rico has been obtained during the ensuing 21 years. Concern for the public health of residents and visitors prompted the formation of the Bilharzia Commission in 1994 and the systematic serosurvey reported herein. Two thousand nine hundred fifty-five plasma samples from healthy donors were obtained randomly from the Red Cross in March and April 1995. Sex, resident municipalities, and age of the donors were recorded. The donors were from all but three of 79 municipalities in Puerto Rico. No sample was available from the three out island municipalities of Mona, Vieques, and Culebra. Male donors (n = 2,027) outnumbered females (n = 928) by more than 2:1, ages ranged from nine to 76 years with most (85.3%) between 19 and 51 years of age. All samples were tested with the Falcon assay screening test:enzyme-linked immunosorbent assay (FAST:ELISA) with microsomal antigens of Schistosoma mansoni. All FAST:ELISA+ samples were confirmed by enzyme-linked immunoelectrotransfer blot (EITB). Our data showed that 15.4% were FAST:ELISA+, and 10.6% were confirmed by EITB; 13.5% of the males and 4.1% of the females were EITB+. If we exclude those municipalities with fewer than five samples, the prevalence of EITB+ ranged from 0% to 38.5%, with the highest seroprevalence rates (21.1-38.5%) concentrated in 17 municipalities, which accounted for 48% of all seropositive samples. These 17 municipalities, however, contain only 18% of the total population of Puerto Rico. Two areas of high seroprevalence rates center around Jayuya (38.5%) and Naguabo (36.4%). The previously surveyed area of Boqueron is located in Las Piedras (35.3%), adjacent to Naguabo. In addition, we found 10% (21) of our total 215 donors less than 25 years of age to be EITB+ and all but two are residents of the high prevalence districts. These data strongly support the contention that schistosomiasis has been transmitted in a focal fashion during the past approximately 20 years.