Phylogeographic and genome-wide investigations of Vietnam ethnic groups reveal signatures of complex historical demographic movements.

The territory of present-day Vietnam was the cradle of one of the world's earliest civilizations, and one of the first world regions to develop agriculture. We analyzed the mitochondrial DNA (mtDNA) complete control region of six ethnic groups and the mitogenomes from Vietnamese in The 1000 Genomes Project (1000G). Genome-wide data from 1000G (~55k SNPs) were also investigated to explore different demographic scenarios. All Vietnamese carry South East Asian (SEA) haplotypes, which show a moderate geographic and ethnic stratification, with the Mong constituting the most distinctive group. Two new mtDNA clades (M7b1a1f1 and F1f1) point to historical gene flow between the Vietnamese and other neighboring countries. Bayesian-based inferences indicate a time-deep and continuous population growth of Vietnamese, although with some exceptions. The dramatic population decrease experienced by the Cham 700 years ago (ya) fits well with the Nam tien ("southern expansion") southwards from their original heartland in the Red River Delta. Autosomal SNPs consistently point to important historical gene flow within mainland SEA, and add support to a main admixture event occurring between Chinese and a southern Asian ancestral composite (mainly represented by the Malay). This admixture event occurred ~800 ya, again coinciding with the Nam tien.

Study of the Huntington's disease IT-15 gene in different ethnic groups in Ecuador.

This study aims to establish the current state of the IT-15 (HTT) gene in different Ecuadorian ethnic groups and patients by determining CAG triplet repeats, compared with the ethnicity of individuals. A total of 412 individuals were studied using nested polymerase chain reaction and Sanger sequencing: 75 individuals were indigenous (Kichwas), 211 mestizos, and 65 Afro-Ecuadorians. We included 31 patients who were clinically diagnosed with Huntington's disease (HD) and relatives of the affected patients (n = 30). Moreover, we correlated the presence of HD in Ecuadorian patients with 46 genetic ancestry-informative insertion-deletion polymorphic markers. We found that 77.20% had <28 CAG repetitions, 18.80% had mutable alleles, 2.27% had incomplete penetrance, and 1.70% reflected >39 repetitions. The average of CAG repetitions was 24 ± 3 for indigenous people; 28 ± 2 for mestizos; and 24 ± 3.2 repetitions for the Afro-Ecuadorians. The ancestral component showed that the main ancestry corresponded to Native Americans (0.873) and European ascendants (0.145), Africans were less represented in the evaluated population (0.018). There was a significant difference between the number of CAG repeats in mestizos and indigenous people (P < .01), suggesting that the Ecuadorian mestizo population has a risk factor for the gene mutation.

Model building and quantitative analysis of a tandem immuno-capturing assay as a screening tool for breast cancer.

The onset of breast cancer appears to occur, on average, a decade earlier in Mexican women in comparison to American or European women. Early detection and prevention of breast cancer are of crucial importance to increase survival and improve quality of life. Based on the molecular elucidation of critical events leading to breast carcinogenesis, a tandem immuno-capturing blood test was developed as a quantitative population screening assay in view of providing a cost-effective and non-invasive alternative to population screening. Clinical analysis of 63 Mexican women within an age group of 35-70, revealed that Interstron activity increases from 800+/-65 IUJPA (Interstron Units) in the asymptomatic normal women to 994+/-100 IUJPA in the symptomatic/benign group, reaching 1289+/-81 IUJPA in the cancerous group. Accordingly, activity thresholds were established at 800 and 1200 IUJPA respectively, encompassing three risk groups: (i) Healthy Otherwise Normal (<800 IUJPA); (ii) Grey Risk Area (>800 and <1200 IUJPA), and (iii) At Risk group (>1200 IUJPA). Taking into account both baseline and clinical case reports, the Healthy Otherwise Normal group and the At Risk group were mostly homogeneous in nature, comprising a population of normal and cancer patients respectively. The Grey Risk group is heterogeneous, likely reflecting a transitional nature towards a potential early stage of breast disease development. Based on these results, a screening algorithm was developed as the underlining principle for population surveillance encompassing over 30,000 Mexican women. The current screening results have enabled us to objectively prioritize medical attention to approximately 1 in 8 women out of the general population mapped within the At Risk group. Overall, our findings suggest that monitoring Interstron activity units provides a valuable quantitative screening analysis as to selectively streamline the population of women in need of early medical counseling and/or mammography, thereby enhancing both the quality and cost-effectiveness of preventative population surveillance programs targeting breast cancer.

Comparative analysis of national regulations concerning blood safety across Europe.

In October 2001, representatives of 17 European countries (Albania, Bosnia-Herzegovina, Bulgaria, Croatia, Czech Republic, Federal Republic of Yugoslavia, Finland, France, Germany, Greece, Italy, Macedonia, Romania, Slovenia, Spain, Turkey and UK) met in Sarajevo at a course organized by the European School of Transfusion Medicine to discuss their countries' regulations concerning different aspects of the safety of blood transfusion. Results are summarized in tables to facilitate comparisons. Most countries (13/17) have specific transfusion laws and 9/17 have hospital-based systems as opposed to national organizations. Quality assurance is common among investigated countries (14/17). Voluntary associations are responsible for donor promotion in the majority of countries (13/17). Exclusively, voluntary non-remunerated donors are found in 5/17 countries, whereas in the remaining ones, incentives, family replacement and remuneration are mechanisms stimulating blood donation. Medical doctors using official selection criteria are checking donor suitability in virtually all countries, which also perform main microbiological testing. Regulations on good clinical use of blood and derivatives are present in most countries but applied only in some. Although the data presented need to be interpreted with some caution, this preliminary analysis shows that, although some significant differences still exist, the majority of countries studied are moving in the same direction to ensure safety of their blood supply.

[Level of medical information on diabetes, attitude of patients towards their illness and its association with the level of blood sugar control]. / Nivel de información médica sobre diabetes, actitud de los pacientes hacia la enfermedad y su asociación con el nivel de control glucémico.

OBJECTIVE: To determine the level of information and attitude that it has more than enough their illness has patient with diabetes type 2 (DM2), and their association with level of glycemic control. DESIGN: Cross-sectional. SETTING: Two units of family medicine. PATIENT: 200 subject with DM2. INTERVENTIONS: Two instruments were applied validated to measure, level of knowledge and attitude was measured the average of the last 6 glycemia. MEASUREMENTS AND RESULTS: The qualification average of the instrument of knowledge was 58.6 +/- 17.9 (it scale 0-100). For the instrument of attitude it was of 18.9 +/- 2.1 (it scale 0 at 35). The qualification of knowledge of the controlled group was of 55.48 +/- 16.8, and of the uncontrolled group it was of 59.2 +/- 18.1. The qualification has more than enough attitude of the controlled group it was of 17.8 +/- 2.3, and of the uncontrolled group of 19.1 +/- 2, p = 0.001. The proportionate level of information the family doctor was of 42.9%, of the team of health of 10.2% and of other sources of 6.3%. At the analysis of the degree of attitude and the level of information, there was a better attitude when the information was provided by other sources p < 0.05. In the percentage of information and the level of glycemic control, the control level was better when the information was for the team of health p < 0.01. CONCLUSIONS: The level of medical information on diabetes provided by the family doctor and the team of health is low and it doesn't and only this last are associate to better glycemic control. The attitude is better when one receives information of other sources.

Láser blando en el tratamiento de las quemaduras: estudio comparativo / Soft laser in the treatment of the burn patients

Con el fin de determinar el efecto benefico del laser blando o de baja potencia (laser infrarrojo), en la cicatrizacion de las heridas, se diseño un ensayo clinico controlado y aleatorio con dos grupos de pacientes quemados del Hospital Universitario San Vicente de Paul de Medellin, entre marzo y octubre de 1992. El grupo A estuvo conformado por 11 pacientes tratados con el esquema convencional de manejo de las quemaduras, y el grupo B, por 12 pacientes tratados en forma similar adicionado con radiacion laser de 3 minutos de duracion diariamente, sobre el area lesionada. Se encontro una disminucion en el grupo tratado con el laser blando, tanto en el promedio de dias de hospitalizacion (15.1 vs 25.8), como en el tiempo requerido para la yanulacion total (17.6 vs 20) y la epitelizacion (11 vs 14). Mediante biopsia cutánea se demostro una mejor regeneracion epitelial en la piel irradiada que en los casos tratados con el metodo convencional (15.2 capas epiteliales en promedio vs 10.4). Aunque estas diferencias no fueron estadisticamente significativas, apuntan a demostrar un beneficio de la radiacion con laser de baja potencia, en la cicatrizacion de areas quemadas.

Human interleukin 2. Quantitation by a sensitive radioimmunoassay.

Using polyclonal and monoclonal antibodies to human recombinant IL-2 (rIL-2), we developed a sensitive radioimmunoassay (RIA) for quantitation of human IL-2. In this assay, microtitration plates pre-coated with an anti-rIL-2 monoclonal antibody (35H10), recognizing residues 59-72 of human IL-2, are incubated with serial dilutions of test samples. Captured IL-2 is quantitated by adding an affinity-purified rabbit anti-rIL-2 antibody followed by an 125I-labeled goat anti-rabbit IgG. Antibodies to chemically synthesized IL-2 peptides could replace the polyspecific rabbit anti-rIL-2 antibody as the second specific reagent in the assay. This configuration was more sensitive than others tested, approaching the level of detection of the conventional IL-2 bioassay, thus allowing detection of as little as 100-200 pg IL-2. Serum or plasma fluids, however, inhibited the assay, reducing its sensitivity by approximately 5-fold. This RIA correlated well with the conventional bioassay in measuring IL-2 levels in sera from IL-2-treated patients. This, and similar, RIAs may serve as a useful adjunct or alternative to the conventional IL-2 bioassay in detecting and quantitating human IL-2 in culture supernatants and clinical samples.

Antibodies of predetermined specificity against chemically synthesized peptides of human interleukin 2.

This communication describes the preparation of antibodies to human interleukin 2 (IL-2), using as immunogens synthetic peptides derived from the predicted amino acid sequence of IL-2. Rabbits and mice were immunized with protein carrier conjugates of eight chemically synthesized IL-2-derived peptides, each consisting of 13-15 amino acids. The immune antisera were screened in a solid-phase ELISA for reactivity to a native human IL-2. Antibodies to four of the eight peptides were found by a variety of biological and immuno-chemical criteria to react against human IL-2. Furthermore, an affinity-purified antibody to one of the IL-2 peptides (peptide 84) specifically stained the cytoplasm of phytohemagglutinin-stimulated human peripheral blood lymphocytes or T-leukemic cells (Jurkat). Antibodies to synthetic IL-2 peptides should serve as useful probes for studying this lymphokine and for developing quantitative assays for measuring its levels in biological fluids and its association with disease.

Essential arginine residues occur in or near the catalytic site of L-amino acid oxidase.

Butanedione in borate buffer irreversibly inactivates L-amino acid oxidase. L-Phenylalanine and L-methionine, which are good substrates for the enzyme, protect against inactivation but glycine, which is a very poor substrate, and D-phenylalanine which is neither substrate nor inhibitor, do not provide significant protection. These results are consistent with the modification by butanedione of one or more arginine residues located in or near the catalytic site of L-amino acid oxidase.

Immunoelectron microscopic study of the detection of the glycoproteins of influenza and Sendai viruses in infected cells by the immunoperoxidase method.

The envelope glycoproteins of influenza virus (HA and NA) and paramyxovirus (HN and F) were visualized on the surface of infected cells by immunoelectron microscopy using the indirect immunoperoxidase technique. In X7 influenza virus-infected fibroblasts, the hemagglutinin (HA) and the neuraminidase (NA) were observed on the cell membrane respectively 2 and 3--4 h after infection. The antigens were initially seen as discrete patches and later evenly distributed along the plasma membrane prior to budding. Antibody induction of HA and NA was observed as cytoplasmic inclusions, with peroxidase-positive activity, attributed to endocytosis. The redistribution of HA and NA supports the hypothesis of lateral mobility of the viral glycoproteins in cellular membranes as visualized by the immunoperoxidase method. The glycoproteins of Sendai virus, in infected Madin--Darby bovine kidney cells, were found to be evenly distributed along the plasma membrane and endoplasmic reticulum, the latter by the indirect microperoxidase method. The immunoperoxidase methods may be useful for investigating the polarized distribution of envelope glycoproteins.

Single subunits of Sepharose-bound pyruvate kinase are inactive.

Bovine skeletal muscle pyruvate kinase was covalently coupled to Sepharose that had previously been activated by low concentrations of cyanogen bromide. Reaction conditions were chosen such that essentially all tetrameric enzyme molecules were covalently bound via a single subunit. Denaturation of the immobilized enzyme with guanidine hydrochloride followed by removal of noncovalently bound subunits amd denaturant resulted in essentially no enzymatic activity remaining bound to the resin. Thus, single immobilized subunits of bovine pyruvate kinase were inactive. Sepharose-bound enzymatic activity could be recovered by adding soluble renaturing enzyme subunits to the immobilized monomers. The former combine noncovalently with the latter, presumably resulting in re-formation of bound tetramers, and an average recovery of 61% of the original matrix-bound activity was observed. While interactions with other enzyme subunits appear to be necessary for catalytic activity of bovine muscle pyruvate kinase, these subunit interactions apparently can be provided by chemically modified subunits. Soluble, renaturing subunits from enzyme that had been inactivated by treatment with trinitrobenzenesulfonic acid were able to interact with matrix-bound single subunits, thereby restoring the enzymatic activity of the latter.

Analysis of the renaturation kinetics of bovine muscle pyruvate kinase.

Bovine type M pyruvate kinase can be reversibly denatured by solutions of guanidine-HCl. Subsequent dilution of the enzyme into buffer containing 2-mercaptoethanol or dithiothreitol results in recovery of enzymatic activity with half-times that vary from 185 min at 0 degrees C to 4 min at 45 degrees C. In the temperature range 0-25 degrees C, 90% of the enzymatic activity is recovered. Above about 32 degrees C, the recovery drops off sharply, wih a yield of only 13% at 45 degrees C. Removal of inactive nonspecific aggregates and denatured monomer by gel filtration yields an enzyme with the same specific activity as the starting material. At enzyme concentrations below 3 microns/mL at 16 degrees C or below 25 micron/mL at 7.8 degrees C, the reactivation kinetics show a concentration dependence. At higher concentrations of protein and at temperatures of 16 degrees C or higher, no protein concentration dependence is seen, and the rate of reactivation is described by two first-order relaxations. The rate constants have apparent activation energies of 10.6 and 11.9 kcal/mol. Combinding the results presented here with earlier work from this laboratory [Cardenas, J. M., & Dyson, R. D. (1973) J. Biol. Chem. 248, 6938-6944; Cardenas, J. M., Hubbard, D. R., & Anderson, S. (1977) Biochemistry 16, 191-197] leads to the conclusion that a rapid, major folding produces two species which undergo transconformational steps. This is followed by subunit association which yields the native tetramer.

The biological effects of allogeneic effect factor (AEF) on T lymphocytes. III.--Interferon does not contribute to the biological activities displayed by AEF on both T and B lymphocytes.

The studies reported here were designed to evaluate the potential contribution of interferon (IF) to the biological activities mediated by allogeneic effect factor (AEF), a soluble product of allogeneic cell interactions, on responses of T and B lymphocytes. AEF supernatants were found to contain varying levels of IF, predominantly of type II (immune). AEF preparations which were practically free of--or very low in--IF activity were obtained by bovine serum albumin-Sepharose chromatography of AEF, or by using strain combinations involving K-only or I-only differences within the H-2 complex for the production of AEF. Such preparations retained their biological activities in three in vitro assays characteristic of AEF: (a) induction of primary self-H-2-reactive cytotoxic T-lymphocyte responses, (b) mitogenicity for normal T cells, and (c) induction of plaque-forming cell antibody responses to a T-dependent antigen in T-cell-depleted spleen cultures. These results demonstrate that IF does not play any significant role in the biological activities medicated by AEF.

Pyruvate kinases of salmon: purification and comparison with the isozymes from birds and mammals.

Pyruvate kinase occurs as two major forms in coho salmon; the type M isozyme occurs primarily in muscle and heart, but type K has a more generalized tissue distribution, in parallel with the type K isozyme in other vertebrate systems. In order to assess the evolutionary relationships among the fish, avian, and mammalian isozymes of pyruvate kinase, we have purified the two isozymes from fish, have examined some of their physical properties, and have studied their immunological relationships to the avian and mammalian isozymes. Salmon type K is at least partially inactivated by antibody to bivine type L pyruvate kinase as well as by antibodies produced against chicken, bovine, and salmon type M isozymes. Salmon type M pyruvate kinase, on the other hand, is not significantly corss-reactive with the bovine type L isozyme, but is at least partially inactivated by antibodies produced against bovine or chicken type M isozymes. Mammalian type L pyruvate kinase is immunologically distinct from either mammalian type K or type M, but salmon type K has some structural features in common with all three mammalian isozymes. Thus, salmon fish type K pyruvate kinase could be similar to a primordial form that was antecedent to the three major differentiated isozymes of higher vertebrates.