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PubMed2000

Early morphologic alterations in trophically deprived neuronal death in vitro occur without alterations in cytoplasmic Ca(2+).

Morphologic and functional parameters altered during neuronal death were investigated in chick ciliary ganglion (CG) neurons in vitro isolated from embryonic day 8 (E8, stage 34). Neurons were separated from nonneuronal cells to investigate their inherent cell death program and were cultured with or without trophic support (choroid, iris, pigment epithelium) from their appropriate target tissue. The cell death process was characterized with investigations focused on the earliest events at the onset of commitment to cell death at 11 hours after plating. Initial morphologic changes in the process of cell death were cytoplasmic; swelling, dendritic retraction, blebbing, vacuolization, which are all characteristics of necrosis. Later, nuclear chromatin condensation occurred, a characteristic of apoptosis. An increase in membrane permeability was measured earlier at 8 hours. During these alterations (associated with the initiation of cell death) single cell analysis was performed to evaluate mobile Ca(2+) changes in the same trophically deprived neurons during the course of the death process; Ca(2+) levels remained at 50 nM. Transient Ca(2+) entry was buffered in control and deprived cells at 13 hours but with different parameters. During the execution stage of death mobile Ca(2+) levels were variable. In this final stage of cell death, neurons demonstrated nuclear damage, cytosol disintegration, or morphology sharing both characteristics. These observations define embryonic CG cell death in vitro as neither purely apoptotic nor necrotic but a form of that exhibits features of both. These results also demonstrate a disassociation of changes in cytosolic Ca(2+) from both CG neuronal survival and trophically deprived cell death in vitro.

Animals↗

PubMed1992

[DNA synthesis and content in human decidual cells at different stages of differentiation based on flow cytometry data].

Flow cytometry analysis of the DNA content of human decidual cells at the physiologically normal pregnancy and in the case of toxicosis was carried out. During the normal pregnancy DNA-histogram parameters were seen to vary: the number of S-phase cells decreased, the coefficient of variation of the G1/0 peak increased. These alterations correlated positively with the increase in the share of decidual cells with properties of terminally differentiated cells. The most pronounced quantitative alterations in variability of DNA content in G1/0 cells were observed in cases of toxicosis of pregnancy. Phenomena of variability of the nuclear DNA in the terminally differentiated decidual cells is considered to be a sign of cell death through apoptosis.

Adolescent↗

PubMed2004

A case study of successful patient flow methods: St. John's Hospital.

Participating in the Institute for Healthcare Improvement (IHI) IMPACT collaborative has given St. John's Hospital the opportunity to improve patient flow and the delivery of patient care. This partnership has allowed us to experience a wealth of information shared by a collaborative network of hospitals. IHI has introduced rapid-cycle improvement methodologies, variability-reduction strategies, and strategies to aid in planning for the expected as methods that have enhanced our already established performance-improvement program. St John's has achieved breakthrough improvement with patient flow.

Academies and Institutes↗

PubMed2005

Constructing and testing a model of trustworthiness, trust behavior and organizational identification.

This study, in which staff nurses in Taiwan participated, was aimed to construct a model for relationships among trustworthiness, trust behavior and organizational identification. One hundred and ninety five anonymously completed questionnaires were collected. Superiors' trustworthiness, staff nurses' trust behavior, and organizational identification were identified as latent variables to which the following indicators were to be applied: integrity, benevolence, ability, communication, consistency, compliance, sharing, teamwork, subordination, membership, loyalty and similarity. A logical trust and organizational identification model was constructed and tested with LISREL (Linear Structural Relations) analysis. Benevolence was eliminated due to excessive residual value. The adjusted model passed pertinent tests. It was also revealed that trust behavior acts as a mediator between trustworthiness and organizational identification. The results of this study may be taken as a reference for the training of supervisory level personnel, as well as for strengthening the organizational identification of staff nurses, and as a beginning phase in the construction and testing of a relationship model for the relationship between trust and organizational identification.

Adult↗

PubMed1986

Primary pulmonary hypertension. An analysis of 28 cases and a review of the literature.

The diverse potential etiologies and varying degrees of severity at the time of presentation suggest that primary pulmonary hypertension is a spectrum of disease states, all of which share the hemodynamic and pathologic correlates of pulmonary hypertension without a demonstrable cause. The course is variable, but manifestations of a low cardiac output or right ventricular failure imply a poor prognosis; the median survival is 2 to 3 years from the time of diagnosis. Although several systemic vasodilators have been demonstrated to improve pulmonary hemodynamics and ameliorate symptoms in some cases, these drugs may produce undesirable adverse effects, including death, in unresponsive patients. Additionally, the impact of vasodilator therapy on mortality from PPH has not been assessed. Combined heart-lung transplantation should be considered in patients who are unresponsive to vasodilators and who manifest the indicators of a poor prognosis.

Adolescent↗

PubMed1985

Pediatricians' and psychologists' implicit personality theory: significance of sibling differences.

Pediatricians' and psychologists' implicit theories of how personality develops are compared to recent behavioral-genetic analyses based on twin and adoption studies. Results show that both practitioner groups--less so the psychologists--underestimate differences between children in the same family, over-estimate the influence of their shared environmental experiences, and underestimate those not shared. Findings mirror the bias of traditional personality research, pointing out the need to investigate environmental variables with differential impacts on children in the same family, e.g., sibling deidentification; one child extrovert, one introvert; one saint, one sinner.

Child↗

PubMed1984

[Symptoms and incidence of hypoglycemia in 100 insulin dependent diabetics].

The aim of this study was to discover the frequency and the symptoms of hypoglycaemic reaction and coma. One hundred type I diabetic patients answered an oral questionnaire and explained how they were awaken from their hypoglycaemicoma. The frequency of hypoglycaemic reaction was from one a day to one a year. 41 patients had nocturnal hypoglycaemic reactions. Our patients described 27 different symptoms of oncoming attack; however, not all of these symptoms was experienced by any one of the patients. Treatment of hypoglycaemic reaction was administered correctly but at the precise moment of the interview, 13% of patients had no carbohydrates with them. 42 patients had had hypoglycaemic reaction but no coma. Shared between 48 patients were 578 insulin years and 148 comas. Treatment of hypoglycaemic coma was variable: 20 patients remained at home receiving appropriate treatment; 33 were always hospitalised on attack and 20 were still comatous on each admission. The explanation of hypoglycaemic attack was variable; an emotional factor was given by 19% of patients. Both type I diabetic patients and their immediate entourage should be made aware of all the symptoms of oncoming attack and of the treatment of hypoglycaemic coma. Systematic glycemic auto control should testify to the existence of genuine hypoglycaemic reaction and perhaps diminish its supposed frequency.

Adolescent↗

PubMed1994

Self-help groups: a key to HIV risk reduction for high-risk injection drug users?

While recent studies indicate that injection drug users (IDUs) can change their behavior to reduce injection risk of HIV, it remains unclear which users are most likely to change and which mediating variables are most amenable to intervention. We report a study in which a cohort of high-risk IDUs was followed over time to determine which variables were associated with reduced injection risk of HIV. Of 317 IDUs who at baseline had shared a dirty needle in the previous 30 days, 234 (74%) were followed for 6 months. Of these, 107 (46%) reported reduced or eliminated injection risk between the baseline and follow-up interviews, 82 (35%) by not injecting and 25 (11%) by not sharing syringes. Those who attended self-help meetings between the two interviews were almost twice as likely to report reduced or eliminated risk as those who did not attend (OR = 1.92; p = 0.04). The findings suggest that, at least, IDUs in self-help groups comprise a population amenable to HIV interventions and, at most, that self-help groups may play an important role in reducing the risk of HIV in out-of-treatment populations.

Adult↗

PubMed1999

The orientation and nature of the interaction between beef insulin-specific TCRs and the insulin/class II MHC complex.

Recent crystallographic studies suggest that TCR interact with peptide/class I MHC complexes in a single preferred orientation. Although similar studies have not been performed for class II-restricted TCR, it has been proposed that T cell recognition of peptide/class II complexes has similar orientational restrictions. This study represents a functional approach to systematic analysis of this question. Twenty-one mutant A beta(d) molecules were produced by alanine scanning mutagenesis and assessed for their ability to present species variants of insulin to a panel of beef insulin-specific T cell hybridomas with limited TCR alpha- and/or beta-chain sequence differences. We demonstrate that all beef insulin-specific TCR have the same orientation on the insulin/Ad complex, such that the alpha-chain interacts with the carboxyl-terminal region of the A beta(d) alpha-helix, and the beta-chain complementarity-determining region 3 interacts with the carboxyl-terminal portion of the peptide, consistent with that observed for crystallized TCR-peptide/class I complexes. Despite this structural constraint, even TCR that share structural similarity show remarkable heterogeneity in their responses to the panel of MHC mutants. This variability appears to result from conformational changes induced by binding of the TCR to the complex and the exquisite sensitivity of the threshold for T cell activation.

Amino Acid Sequence↗

PubMed1999

Spontaneous sister chromatid exchange and chromosome aberration frequency in humans: the familial effect.

The possible effects of environmental and genetic factors on spontaneous frequencies of sister chromatid exchanges (SCEs) and cells with chromosome aberrations (CAs) in human lymphocytes were investigated by analysing 177 completed families (mother, father and at least one child). After removing the effects of methodological, biological and life-style factors by the use of multifactor analysis of variance (MANOVA), SCEs and CAs residuals were analysed by simple correlation analysis and principal component analysis. SCEs and CAs inter-familiar variability was higher than that found within families. A significant correlation was found between the average SCE frequencies shared by parents (the so-called 'midpoint parents', or 'midparent') and offspring (linear slope b=0.26+/-0.07, p<0.05), but also between mother and father (b=0.23+/-0.11, p<0.05) suggesting the presence of an effective environmental factor. The midparent-offspring correlation was found to be sustained by the mother-offspring relationship (b=0.28+/-0.08, p<0.05), being the father-offspring correlation not significant (b=0.16+/-0.11, p0.05). Concerning CAs, no statistically significant correlation between parents was found, but the strong relationship between mother and offspring was confirmed (b=0.468+/-0.11, p<0.001). The SCEs correlation between mother vs. offspring disappeared for older offspring (over 23 years old). The obtained findings strongly showed that the genetic make-up is barely detectable in the presence of domestic environment factors which are shown to play the major role in determining the interfamilial variability of SCE and CA in a general population. These results strengthen the suitability of the use of SCEs and CAs analysis in human cytogenetic surveillance for the detection of effective environmental factors.

Adult↗

PubMed1983

T and B cells that recognize the same antigen do not transcribe similar heavy chain variable region gene segments.

We have attempted to determine whether T cells and B cells that have the same antigenic specificity and whose receptors share idiotypic determinants in fact express similar VH gene segments. To do this, we have obtained and characterized a cDNA clone containing the entire coding sequence for the VH gene from a glutamic acid60/alanine30/tyrosine10 (GAT)-binding immunoglobulin that carries the CGAT idiotype. The GAT-VH clone was hybridized to Northern blots of GAT-specific T cell RNAs; there was no evidence of a T cell transcript that hybridized to the GAT-VH probe. The T cells analyzed included: (a) 10 GAT-binding suppressor T cell hybridomas, 6 of which secreted factors with CGAT idiotypic determinants, (b) one GAT-specific helper T cell hybridoma, and (c) two GAT-specific helper T cell lines grown in the absence of feeder cells. The detection limit of the Northern blot analysis was 1-2 copies of a particular mRNA species per cell for the hybridomas and 5-10 copies per cell for the T cell lines. Therefore, we conclude that T and B lymphocytes responding to GAT do not utilize similar VH gene segments. Furthermore, the presence of idiotypic determinants on T lymphocytes does not necessarily imply close structural similarity between T and B cell antigen receptors.

Animals↗

PubMed2006

Mitochondrial DNA analyses of the Cape hakes reveal an expanding, panmictic population for Merluccius capensis and population structuring for mature fish in Merluccius paradoxus.

The Cape hake species, Merluccius capensis and Merluccius paradoxus are the most important resource of the South African and Namibian demersal fishery, but it is unclear whether there is a single population of each shared by both countries. We analysed the population structure and evolutionary history of these two species using the variable 5' region of the mtDNA control region for 311 specimens of M. capensis and 333 specimens of M. paradoxus sampled between Lüderitz (southern Namibia) to south of Cape Point (South Africa). 107 haplotypes for M. capensis and eight haplotypes for M. paradoxus were recovered. AMOVA and pairwise Phi(st) analyses revealed no structure in M. capensis, however significant genetic differentiation between Namibian and South African 'populations' was detected for M. paradoxus. This was only restricted to mature fish older than 3 and 4 years and not for juvenile fish younger than 3 years. Analyses reveal that M. capensis has undergone population expansion (Fu's Fs=-26.65, P<0.001), possibly within the last 4500-23,000 years, whereas M. paradoxus has not. Our study highlights the utility of genetic markers to unravel the evolutionary history of sympatric species, as well as addressing management issues within regions where commercially valuable fish stocks are shared between nations.

Animals↗

PubMed1996

HLA-DRB1 and DQB typing of Hispanic American patients with rheumatoid arthritis: the "shared epitope" hypothesis may not apply.

OBJECTIVE: To determine whether the association of particular MHC class II alleles and the DRB1 "shared epitope" with disease susceptibility and severity in rheumatoid arthritis (RA) applies to ethnic groups other than Caucasian Americans. METHODS: 67 Hispanic American patients with RA and a similar number of ethnically matched controls were typed for DRB1 using polymerase chain reaction methods. DR4 subtype and DQB1 type were determined for the subjects positive for DR4. Disease severity in the patients with RA was assessed by clinical, radiographic and laboratory variables. RESULTS: The frequency of DR4 was significantly increased in the subjects with RA compared to the control group. However, the "shared" DRB1 amino acid sequence was relatively infrequent in the Hispanic American patients with RA, and there was no association of specific DR4 or DQ alleles with more severe disease or extraarticular manifestations. CONCLUSION: The HLA markers that predict poor prognosis and suggest that more aggressive clinical management may be appropriate in Caucasian American patients with RA may not be useful in other ethnic groups.

Arthritis, Rheumatoid↗

PubMed2000

Cultural differences: implications on drug therapy and global drug development.

INTRODUCTORY REMARKS: Discussing the "inter-ethnicity" of kinetics and actions of drugs is fraught with terminology problems. It is, however, generally accepted that "ethnicity" covers the influences of factors genetically and culturally transmitted. The study of inter-ethnic variability in drug response addresses the problem of distinguishing variability factors that are common to one particular group of individuals from those which are not specifically shared. DIFFERENCES IN DAILY DOSES BETWEEN DIFFERENT GEOGRAPHIC REGIONS: It is well known that for a number of drugs, the daily dose prescribed in Japan is lower than in the US and Europe. Presently, independent surveys strongly indicate that for a majority of drugs dose differences are not the result of pharmacokinetic differences. In addition, they indicate that inter-ethnic differences do not seem to be larger than intra-ethnic variations. The differences observed for daily doses must thus be found elsewhere than in pharmacogenetic traits. DIFFERENCES IN DIAGNOSES: The most important impediments encountered in the evaluation of minority patients include differences with respect to language, communication style, cultural belief. The same problems arise if studies performed in different geographic areas are compared, socio-economic aspects play then an even greater role. Language problems arise differently if minorities are evaluated and compared to a majority of patients living in the same country or if clinical studies are performed in different regions. Communication styles also differ markedly between cultures. As an example, certain gestures may be considered as disrespectful or insulting by some ethnic groups and constitute normal behavior in others. RATING SCALES: Ethnicity clearly plays a role on the cross-cultural use of rating scales. Sophisticated rating scales established and validated in Western culture must undergo culturally sensitive revision and rigorous evaluation before their use in non-Western culture. EFFICACY-SAFETY ASSESSMENT: As an example, the assessment of risk and benefit is different in Japan, Europe and the United States. In Japan, safety is given a greater weighting relative to efficacy than in the two other regions. PLACEBO/NOCEBO EFFECTS: Placebo and nocebo effects are difficult to study, even in the absence of any cultural difference. They are even more so if ethnicity is concerned. PATIENT COMPLIANCE: Clinicians treating cross-cultural patients must carefully explore the beliefs held by their patient regarding illness causality and treatment expectations. CONCLUDING REMARKS: There are many unanswered questions in the field of inter-ethnic variability in drug response. The present overview will not pretend to have given specific answers, but it is hoped that it will point to some areas where more research is needed, in particular in the area of methodologies to take inter-ethnicity into account during drug development.

Cross-Cultural Comparison↗

PubMed2006

A CAPS test allowing a rapid distinction of Penicillium expansum among fungal species collected on grape berries, inferred from the sequence and secondary structure of the mitochondrial SSU-rRNA.

Penicillium expansum is a fungal species highly damageable for the postharvest conservation of numerous fruits. In vineyards, this fungus is sometimes isolated from grape berries where its presence may lead to the production of geosmin, a powerful earthy odorant, which can impair grapes and wines aromas. However, the discrimination of P. expansum from related fungi is difficult because it is based on ambiguous phenotypic characters and/or expensive and time-consuming molecular tests. In this context, the complete sequences and secondary structures of Penicillium expansum and Penicillium thomii mitochondrial SSU-rRNAs were achieved and compared with those of two other phylogenetically related Ascomycota: Penicillium chrysogenum and Emericella nidulans. The comparison has shown a high conservation in size and sequence of the core and of the variable domains (more than 80% of nt identity) of the four SSU-rRNAs, arguing for a close phylogenetic relationship between these four species of the Trichocomaceae family. Large (from 10 to 18 nt) inserted/deleted (indel) sequences were evidenced in the V1, V5 and V6 variable domains. The size variations (10 to 18 nt) of the V1 indel sequence allowed the distinction of the four species; the V5 indel (15 nt) was specifically recovered in E. nidulans; the V6 indel (16 nt), shared by the three Penicillium species, was lacking in E. nidulans. A couple of conserved primers (UI/R2) were defined to generate a PCR product containing the V1 to V5 variable domains. This product contained the two regions of the four SSU-rRNAs showing the highest rates of nt substitutions, namely the V2 variable domain and, surprisingly, a helix (H17) of the core. The H17 sequence was shown to specifically possess in P. expansum a recognition site for the ClaI restriction endonuclease. Hence, this enzyme generates a digestion pattern of the PCR product with two bands (350 bp+500 bp), specific to P. expansum and easily separable by agarose gel electrophoresis. This leads to a CAPS test usable for P. expansum discrimination among grape berries isolated filamentous fungi. The CAPS test was validated by a comparative analysis involving 29 strains belonging to 17 species currently isolated from grape berries in the Bordeaux vineyards.

Base Sequence↗

PubMed1987

Help with prenatal household tasks and newborn birth weight: is there an association?

Although prenatal psychosocial factors influence pregnancy outcome, the specific components of prenatal social support which affect infants' birth weight have not been examined prospectively. To define those elements of prenatal social support which are associated with newborn birth weights, we studied 198 indigent mothers seen consecutively by a social worker at a community hospital-based obstetrical clinic. At the first prenatal clinic visit, we used the Maternal Social Support Index (MSSI) to assess the availability of help with daily tasks, a communicative male and other adults, emergency child care, and community involvement. The only MSSI item related to low birth weight (LBW less than or equal to 2,500 g) for both multigravida and primigravida mothers was daily task sharing. Help with grocery shopping and the process of paying bills (p = 0.0007) were both significantly associated with LBW for multigravida mothers. Significant items for primigravida mothers included help with inside cleaning (p = 0.03) and working outside (p = 0.005). Help with things around the house was associated with LBW for both multigravida (p = 0.02) and primigravida (p = 0.04) mothers. Car availability was associated with low birth weight only for multigravida mothers (p = 0.006). Stepwise discriminant function analysis was performed for multigravida mothers. Low birth weight was the dependent variable. Eight well-known risk factors for low birth weight (excluding daily tasks) were the independent variables. The "best" function included marital status, maternal age, gravidity, and smoking during pregnancy. The addition of daily task-sharing to this model increased sensitivity (low birth weight classified low birth weight by the model) from 21% to 50%.(ABSTRACT TRUNCATED AT 250 WORDS)

Activities of Daily Living↗

PubMedDate not supplied

Does a theory of language need a grammar? Evidence from Hebrew root structure.

Hebrew constrains the occurrence of identical consonants in its roots: Identical consonants are acceptable root finally (e.g., skk), but not root initially (e.g., kks). Speakers' ability to freely generalize this constraint to novel phonemes (Berent, Marcus, Shimron, & Gafos, 2002) suggests that they represent segment identity-a relation among mental variables. An alternative account attributes the restriction on identical phonemes to their feature similarity, captured by either the number of shared features or their statistical frequency. The similarity account predicts that roots with partially similar consonants (e.g., sgk) should be at least as acceptable as roots with fully identical consonants (e.g., skk), and each of these roots should be less acceptable than dissimilar controls (e.g., gdn). Contrary to these predictions, three lexical decision experiments demonstrate that full identity is more acceptable than partial similarity and (in some cases) controls. Speakers' sensitivity to consonant identity suggests that linguistic competence, in general, and phonology, in particular, encompass a computational mechanism that operates over variables. This conclusion is consistent with linguistic accounts that postulate a symbolic grammatical component that is irreducible to the statistical properties of the lexicon.

Humans↗

PubMed2003

Evolution of sfbI encoding streptococcal fibronectin-binding protein I: horizontal genetic transfer and gene mosaic structure.

Streptococcal fibronectin-binding protein is an important virulence factor involved in colonization and invasion of epithelial cells and tissues by Streptococcus pyogenes. In order to investigate the mechanisms involved in the evolution of sfbI, the sfbI genes from 54 strains were sequenced. Thirty-four distinct alleles were identified. Three principal mechanisms appear to have been involved in the evolution of sfbI. The amino-terminal aromatic amino acid-rich domain is the most variable region and is apparently generated by intergenic recombination of horizontally acquired DNA cassettes, resulting in a genetic mosaic in this region. Two distinct and divergent sequence types that shared only 61 to 70% identity were identified in the central proline-rich region, while variation at the 3' end of the gene is due to deletion or duplication of defined repeat units. Potential antigenic and functional variabilities in SfbI imply significant selective pressure in vivo with direct implications for the microbial pathogenesis of S. pyogenes.

Adhesins, Bacterial↗