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Hispanic Americans in the United States: Young, dynamic and diverse.

Hispanic Americans are a rapidly growing population group, with numbers that increased 53 percent between 1980 and 1990. In 1994 Hispanics numbered 26.6 million, accounting for 10.3 percent of the civilian noninstitutional U.S. population. The Census Bureau projects continued rapid growth but at a decreasing rate than in the past. The population totals may exceed 31 million by the year 2000 and 96 million by 2050. According to the Census Bureau, Hispanic Americans may surpass African Americans as the largest U.S. minority group by the year 2005. While Hispanics present a varied social and economic portrait, they are likely to be young and economically active. As a group, they tend to trail the rest of the U.S. population in terms of educational attainment, occupational status and income. Hispanics are much more likely to be living below the poverty level and less likely to have health insurance than other U.S. populations. The origins and migration patterns vary both between and among the various groups. Each group has tended to settle in a few states with close to 90 percent of all Hispanics living in just nine states. Low educational attainment, combined at times with a lack of English language and other job skills, tends to confine Hispanics to the lower-paying, less stable and more hazardous occupations. Low income and larger family size translate into higher poverty rates, particularly among children. That, in turn, may affect children's ability to realize their full educational potential. Still, Hispanics, particularly men, have high labor force participation rates and will become an expanding part of the future labor force. As such, they will be expected to contribute to the retirement benefits of an ever aging U.S. population.

Adolescent↗

Inactivation of H19, an imprinted and putative tumor repressor gene, is a preneoplastic event during Wilms' tumorigenesis.

Genetic evidence shows that the parent of origin-dependent expression patterns of the Igf2 and H19 genes is coordinated in mouse, such that H19 controls the activity of Igf2 in cis. Equally compelling evidence for a similar situation in humans is absent, although the frequently observed activation of the maternal IGF2 allele (ie., loss of imprinting) in Wilms' tumors has been attributed to the silencing of the maternal H19 locus. We show here that loss of H19 activity is generally a preneoplastic event, which may be linked with an overgrowth lesion that has been proposed to be permissive for tumor formation. Although our results document one instance in which a postneoplastic loss of H19 activity correlates with loss of IGF2 imprinting at the cellular level, it appears that inactivation of H19 is more generally independent of loss of imprinting of IGF2, at least in our specimens. Our results imply that inactivation of H19 correlates with blastema overgrowth and can be independent of a regulatory role with respect to IGF2 imprinting status in cis.

Alleles↗

Innovative collaboration to prevent repeated adolescent pregnancies.

Nurse educators from a university setting and staff from the county health department collaborated to establish an innovative program to prevent repeated pregnancy in adolescents. Called Dollar-A-Day and patterned after the original in Denver, CO, the program was operated jointly for 5 years and today continues to operate under the auspices of the health department. Success of the venture is attributed to use of skills in assessment, building, managing, and evaluating, as described by Loxley (1997). These elements were used to construct a context for collaboration.

Adolescent↗

Nucleosynthetic signatures of the first stars.

The chemically most primitive stars provide constraints on the nature of the first stellar objects that formed in the Universe; elements other than hydrogen, helium and traces of lithium present within these objects were generated by nucleosynthesis in the very first stars. The relative abundances of elements in the surviving primitive stars reflect the masses of the first stars, because the pathways of nucleosynthesis are quite sensitive to stellar masses. Several models have been suggested to explain the origin of the abundance pattern of the giant star HE0107-5240, which hitherto exhibited the highest deficiency of heavy elements known. Here we report the discovery of HE1327-2326, a subgiant or main-sequence star with an iron abundance about a factor of two lower than that of HE0107-5240. Both stars show extreme overabundances of carbon and nitrogen with respect to iron, suggesting a similar origin of the abundance patterns. The unexpectedly low Li and high Sr abundances of HE1327-2326, however, challenge existing theoretical understanding: no model predicts the high Sr abundance or provides a Li depletion mechanism consistent with data available for the most metal-poor stars.

Journal Article↗

The stroboscopic patterns as dissipative structures.

Photic stimulation of the human visual system with uniform but intermittent illumination has been recognized for well over a century to give rise to the perception of complex visual patterns and forms. A review of the literature pertaining to these "stroboscopic patterns" is presented, along with a review of theories addressing their origins. The theories range from attributing the patterns to inhomogeneities in the structure of the eye, to the formation of functional domains of neural activity. A novel account of the origins of the patterns is developed in this paper utilizing advances in the neurobiology of information processing and nonlinear dynamics. This view conceptualizes the patterns as examples of "dissipative structures." These dissipative structures are conceived of as self-organizing macrostates of spatio-temporal coherence, widespread among visual cortical neurons. This self-organization is described in terms of nonlinear dynamics, in which sets of attractors emerge within a neural phase space undergoing constant change as the energy contained within successive volleys of stimulation-induced action currents is recursively dissipated by the visual system through cooperative feedback. The trajectories of activity formed by these attractors may reflect the actual form of the perceived patterns themselves and are thought to correspond to some of the reported properties of "linking fields" in the visual cortex.

Animals↗

Retrospective review of 50 canine intracranial tumors evaluated by magnetic resonance imaging.

Magnetic resonance imaging (MRI) was performed on 50 dogs with intracranial neoplasia. The following tumor features were assessed: axial origin, location, shape, growth pattern, MRI signal intensity, evidence for edema, and paramagnetic contrast enhancement. Histologic diagnosis included 5 intracranially invading nasal tumors, 7 pituitary tumors, 22 meningiomas, 6 choroid plexus tumors, 7 astrocytomas, 1 ependymoma, and 2 oligodendrogliomas. Axial origin, site, shape, and growth pattern were important diagnostic characteristics for tumor type. Signal intensity and contrast enhancement pattern allowed further differentiation. Characteristic MRI features that facilitate diagnosis and prognosis were identified. Accurate diagnosis of tumor type based on these features was not always possible because of similarities in MRI appearance for some tumors. Tissue biopsy remains necessary for definitive diagnosis of intracranial tumors.

Adenocarcinoma↗

Comparability of MMPI and MMPI-2 profile patterns: Ben-Porath and Tellegen's inappropriate invocation of Mahalanobis's D2 function.

Ben-Porath and Tellegen (1995) claimed that the data in the article by Humphrey and Dahlstrom (1995) were improperly analyzed by means of Q correlations between raw scores earned by the individuals in the forensic sample to establish pattern comparability between the original Minnesota Multiphasic Personality Inventory (MMPI; Hathaway & McKinley, 1943) and the Minnesota Multiphasic Personality Inventory-2 (MMPI-2; Butcher, Dahlstrom, Graham, Tellegen, & Kaemmer, 1989), which were then contrasted with Q correlations between the corresponding T-score patterns. Ben-Porath and Tellegen (1995) contended that the Q correlation is affected by random factors and that a generalized distance function, D2, is the only legitimate index of profile comparability. Data are presented here to show that the Q correlation serves as a reliable index of pattern comparability, relatively unaffected by differences in profile elevation. The Mahalanobis (1936) D2 index is too heavily weighted with differences in profile elevation serve as the proper index of equivalence in profile patterning. The findings in the Humphrey and Dahlstrom (1995) article were based on appropriate data-analytic procedures because the primary concern is their investigation was the extent to which the patterns of T-score profiles from the original MMPI and the MMPI-2 are comparable when the raw-score patterns are virtually identical.

Journal Article↗

Clonal analysis of hepatocellular carcinoma and dysplastic nodule by methylation pattern of X-chromosome-linked human androgen receptor gene.

To investigate the monoclonality of hepatocellular carcinoma (HCC) and dysplastic nodule (DN) and the origin of multiple lesions, patterns of inactivation of X-linked human androgen receptor gene were studied. Fourteen of 15 patients (93%) were heterozygous in the size of the target, and were informative for clonal analysis. Monoclonal composition was demonstrated in all 17 HCCs and two DNs, whereas all non-cancerous hepatic tissues were polyclonal. Of four patients with more than two lesions of HCC or DN, two patients had two lesions with different patterns of X-chromosome inactivation, indicating that the two lesions were multicentric in origin.

Adult↗

Comorbidity and breast cancer survival: a comparison between black and white women.

The presence of concurrent health conditions (comorbidity) at the time of breast cancer diagnosis has an adverse effect on survival. It is unclear, however, whether the strength of the association between comorbidity and survival varies in different populations of breast cancer patients. It is necessary, therefore, to establish (1) whether a comorbidity index derived from a general population of patients (mostly white) would predict survival in a black population, and (2) whether comorbidity would have the same degree of relationship to mortality in black as in white populations. We studied 1196 breast cancer patients who were members of the Kaiser Permanente Medical Care Program and were diagnosed with local (n = 708), regional (n = 446), or remote (n = 49) stage breast cancer from 1973 to 1986. Mortality follow-up was completed to December 1994. Ten-year survival was studied in relation to the Charlson comorbidity index for black women and for white women, and for both groups of women combined. Compared to women with a Charlson comorbidity score of 0 (no comorbidity), patients with scores of 1, 2, and 3+ had risk ratios for ten-year mortality of 1.23 (P = 0.10), 2.58 (P < 0.001), and 3.44 (P < 0.001), respectively. This pattern of risk associated with comorbidity was similar to that found in the original Charlson study. The pattern of risk ratios for different levels of comorbidity was very similar for black and white patients. The results confirm previous studies indicating that comorbidity (in particular, the Charlson Comorbidity Index) predicts the survival of women with breast cancer, independently of other factors, such as stage of breast cancer at diagnosis. The Charlson index has prognostic significance for both black and white populations. Research is needed to determine whether the Charlson index can be improved by including health conditions that are particularly prevalent or severe in specific subgroups of women.

Aged↗

Comparative study on triterpene saponins of Ginseng drugs.

A comparative study on the triterpene saponins of 47 samples of Ginseng drugs derived from 12 Panax taxa was conducted using a reverse-phase high-performance liquid chromatography (HPLC)method. Eleven ginsenosides, which represent 4 types of typical sapogenins, were chosen as standards for quantitative determination in order to characterize the chemical constituent pattern of each Ginseng drug and investigate the relationship between genetic varieties and chemical constituent pattern. The results showed that the ginsenoside compositions in Ginseng drugs of different origins were of considerable variability. Total saponin contents varied by 10-fold from the highest drug to the lowest one. Chikusetsu-ninjin derived from P. japonicus (Japan) was found to have the highest content (192.80 - 296.18 mg/g) and Ginseng from P. ginseng to be the lowest (5.78 - 15.63 mg/g). Two main groups (I and II) suggested by phytochemical data were clearly observed; group I mainly containing dammarane saponins consisted of P. ginseng, P. quinquefolius, P. notoginseng, P. vietnamensis and P. vietnamensis var. fuscidiscus; and group II containing a large amount of oleanolic acid saponins was com-posed of P.japonicus (apan), P. zingiberensis, P.japonicus (China),P. japonicus var. angustifolius, P. japonicus var. major, P. japonicus var. bipinnatifidus and P. stipuleanatus. The ratios of the subtotal of dammarane saponins to that of oleanolic acid saponins (D/0) were found to be > 1.9 and < 0.25 for groups I and II, respectively. The drug samples derived from the same botanical origin revealed similar constituent patterns, in other words, each Panaxtaxon showed its own characteristic chromatographic profile,which appeared in the specific shape of an 11-direction radar graph constructed on the basis of the result of quantitative analysis. Similarities of chemical constitution were seen among the closely phylogenetically-related taxa, including P. ginseng and P.quinquefolius, P. vietnamensis and P. vietnamensis var.fuscidiscus,P. japonicus (China) and its varieties were demonstrated, except P. japonicus (Japan) and P. zingiberensis.

Chromatography, High Pressure Liquid↗

Regional differences in rates of plant speciation and molecular evolution: a comparison between eastern Asia and eastern North America.

The eastern Asian (EAS)-eastern North American (ENA) floristic disjunction is one of the best-known biogeographic patterns in the Northern Hemisphere. Recent paleontological and molecular analyses have illuminated the origins of the biogeographic pattern, but subsequent diversification and evolution of the disjunct floras in each of the two continents after isolation remains poorly understood. Although similar in climate and floristic composition, EAS has twice as many species as ENA in genera occurring in both regions. Explaining such differences in species diversity between regions with similar environmental conditions (diversity anomalies) is an important goal of the study of the global patterns of biodiversity. We used a phylogenetic approach to compare rates of net speciation and molecular evolution between the two regions. We first identified EAS-ENA disjunct sister clades from ten genera (Asarum, Buckleya, Carpinus, Carya, Cornus, Hamamelis, Illicium, Panax, Stewartia, and Styrax) that represent diverse angiosperm lineages using phylogenetic analyses of ITS (internal transcribed spacer of nuclear ribosomal DNA) sequence data. Species richness and substitution rate of ITS between sister clades were compared. The results revealed a pattern of greater species diversity in the EAS counterparts. A positive relationship between species diversity and ITS substitution rate was also documented. These results suggest greater net speciation and accelerated molecular evolution in EAS. The data support the idea that a regional difference in net speciation rate related to topographic heterogeneity contributes to the diversity anomaly between EAS and ENA. The close relationship between rates of ITS evolution and species richness further suggests that species production may be directly linked to rate of nucleotide substitution.

Biodiversity↗

[Functional intestinal dyskinesias].

The authors relate the results of examining 120 patients with functional disorders of the colon. The majority of the patients manifested diverse mental abnormalities of the neurotic origin, represented by different patterns of mental pathology, somatized disturbances, neuroses and psychopathies. The conditions favouring the origin of neurotic and functional disorders have been elucidated. It is concluded from the comparison of different treatment modalities that psychotherapy may be preferred.

Age Factors↗

The origins of primitive blood in Xenopus: implications for axial patterning.

The marginal zone in Xenopus laevis is proposed to be patterned with dorsal mesoderm situated near the upper blastoporal lip and ventral mesoderm near the lower blastoporal lip. We determined the origins of the ventralmost mesoderm, primitive blood, and show it arises from all vegetal blastomeres at the 32-cell stage, including blastomere C1, a progenitor of Spemann's organizer. This demonstrates that cells located at the upper blastoporal lip become ventral mesoderm, not solely dorsal mesoderm as previously believed. Reassessment of extant fate maps shows dorsal mesoderm and dorsal endoderm descend from the animal region of the marginal zone, whereas ventral mesoderm descends from the vegetal region of the marginal zone, and ventral endoderm descends from cells located vegetal of the bottle cells. Thus, the orientation of the dorsal-ventral axis of the mesoderm and endoderm is rotated 90( degrees) from its current portrayal in fate maps. This reassessment leads us to propose revisions in the nomenclature of the marginal zone and the orientation of the axes in pre-gastrula Xenopus embryos.

Animals↗

Species distribution and antibiotic resistance patterns of enterococci isolated from food of animal origin in Germany.

Presently, enterococci take the third place of bacterial pathogens associated with nosocomial infections, after staphylococci and Escherichia coli. Especially, the resistances of enterococci to several available antibiotics are threatening. We attempted to determine which species of enterococci could be found in food of animal origin and their significance according to their antibiotic resistances for human beings. From November 2000 to May 2002 we investigated 155 samples of food of animal origin bought in retail outlets in Germany: 27 samples of sausages, 19 of ham, 83 of minced meat, 26 of cheese. From these food samples we isolated 416 enterococcal strains. The most frequent species was Enterococcus faecalis (299 strains); furthermore, we found Enterococcus faecium (54 strains), Enterococcus durans together with Enterococcus hirae (24 strains), Enterococcus casseliflavus (22 strains), Enterococcus avium (9 strains) and Enterococcus gallinarum (8 strains). We focused on the resistance patterns of 118 selected E. faecium and E. faecalis strains to 13 antimicrobial active agents (ampicillin, amoxicillin/clavulanic acid, avilamycin, chloramphenicol, enrofloxacin, erythromycin, flavomycin, gentamicin, penicillin, quinupristin/dalfopristin, teicoplanin, tetracycline and vancomycin). From the clinical point of view, the situation of antibiotic resistance to the examined antimicrobial agents seemed to be favourable. The investigated strains were sensitive to ampicillin and amoxicillin/clavulanic acid. These antibiotics are, in combination with an aminoglycoside, for example gentamicin, agents of choice for the treatment of enterococcal infections in human medicine. Only one E. faecium strain was resistant to penicillin, while all strains were sensitive to the glycopeptide antibiotics, vancomycin and teicoplanin. Resistances found against the antibiotics, tetracycline, quinupristin/dalfopristin and erythromycin, are causes for concern.

Animals↗

Significance of glycosidase patterns in lymphoid cells.

Characteristic patterns of cell bound lysosomal glycosidases were found in different lymphoblastoid cell lines derived from Epstein-Barr virus-transformed lymphocytes. The enzyme pattern resembled that found in normal lymphocytes from healthy individuals except for a marked increase in alpha-L-fucosidase. beta-D-Glucuronidase on the contrary markedly decreased in the lymphoblastoid cells. Burkitt's lymphoma cells on the other hand showed glycosidase patterns that were quite distinct from those in lymphoblastoid cells. Each lymphoma cell line showed a characteristic pattern. This is one indication of a heterogeneous origin of these tumors. Glycosidase patterns may be used to roughly distinguish different lymphoid cell lines.

Cell Transformation, Viral↗

The family systems of Munchausen syndrome by proxy.

Munchausen Syndrome by Proxy describes a parent who fabricates the appearance of physical illness in a child. Previous descriptions of the syndrome have focused exclusively upon medical or psychiatric assessments of the involved child and perpetrating parent. The family evaluations of two cases presented here suggest that Munchausen Syndrome by Proxy may be a systemic syndrome generated when a mother already possessing a somatoform or factitious disorder joins an enmeshed, authoritarian family system possessing a systemic history of exploitation of children. We suggest that measures instituted to protect the abused child must take into account the systemic function of the Munchausen by Proxy behavior in maintaining family stability, lest such measures be rendered ineffective by family members. When there is ongoing victimization of perpetrating parents in a similar pattern of dominance/submission within their own family of origin, disruption of these intergenerational patterns of exploitation may be a necessary component of treatment.

Adult↗

Role of embB codon 306 mutations in Mycobacterium tuberculosis revisited: a novel association with broad drug resistance and IS6110 clustering rather than ethambutol resistance.

Mutations at position 306 of embB (embB306) have been proposed as a marker for ethambutol resistance in Mycobacterium tuberculosis; however, recent reports of embB306 mutations in ethambutol-susceptible isolates caused us to question the biological role of this mutation. We tested 1,020 clinical M. tuberculosis isolates with different drug susceptibility patterns and of different geographical origins for associations between embB306 mutations, drug resistance patterns, and major genetic group. One hundred isolates (10%) contained a mutation in embB306; however, only 55 of these mutants were ethambutol resistant. Mutations in embB306 could not be uniquely associated with any particular type of drug resistance and were found in all three major genetic groups. A striking association was observed between these mutations and resistance to any drug (P < 0.001), and the association between embB306 mutations and resistance to increasing numbers of drugs was highly significant (P < 0.001 for trend). We examined the association between embB306 mutations and IS6110 clustering (as a proxy for transmission) among all drug-resistant isolates. Mutations in embB306 were significantly associated with clustering by univariate analysis (odds ratio, 2.44; P = 0.004). In a multivariate model that also included mutations in katG315, katG463, gyrA95, and kasA269, only mutations in embB306 (odds ratio, 2.14; P = 0.008) and katG315 (odds ratio, 1.99; P = 0.015) were found to be independently associated with clustering. In conclusion, embB306 mutations do not cause classical ethambutol resistance but may predispose M. tuberculosis isolates to the development of resistance to increasing numbers of antibiotics and may increase the ability of drug-resistant isolates to be transmitted between subjects.

Antitubercular Agents↗

[Characteristics of the growth of cells on a surface of limited area].

An original technique was used to study the growth pattern of cells of varying origin on limited areas (from 1 to 0.01 mm2). During cultivation on limited areas, the growth of primary and continuous fibroblast-like cells was inhibited, whereas that of normal and transformed epithelioid cells was not. The growth of fibroblast-like skin cells of diploid lines and human embryonal muscles was completely inhibited in cultivation on 0.1-0.02 mm2 areas and partially inhibited in cultivation on 0.03-0.16 mm2 areas. Other normal fibroblast-like cells used in the experiment were also marked by growth inhibition of varying degree during cultivation on limited areas. The technique suggested and the data thus obtained may be used for studying substrate-cell and cell-cell interactions, selection of epithelioid cells, and the development of optimal microcarrier technology for cell cultures.

Animals↗