SEARCH · PubMed Health

Results for “shared variables”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 811 records · Page 45Linked to original sources

PubMed1993

The carboxyl-terminal domain of the human pregnancy-specific glycoprotein specifies intracellular retention and stability.

The pregnancy-specific glycoproteins (PSGs), which are members of the immunoglobulin superfamily, are the major pregnancy-associated proteins synthesized by the human placenta. Thirty or more PSG members have been identified which are encoded by at least 11 linked genes. The PSG proteins share 85-95% sequence homology in the coding region, but show variability at the carboxyl-terminal (COOH) domains. In the present study, we examined the effects of PSG COOH domains on protein secretion and stability. Using PSGs containing short (11-12 residues) hydrophilic (PSG1e, PSG11s, and PSG16a), short (22 residues) hydrophobic (PSG6r), and long (81 residues) hydrophobic (PSG11w) COOH domains, we showed that most PSG members were secretory proteins except PSG11w which was largely retained in cells. When the PSG11w COOH domain was replaced with a short COOH domain of PSG1e, the resulting PSG-N11w/C1e chimera became secreted into the medium. On the other hand, chimeras that harbored the PSG11w COOH domain, PSG-N1e/C11w and PSG-N16a/C11w, remained in cells, demonstrating that the COOH domain of PSG11w confers intracellular retention. Deletion analysis showed that mutant (PSG11w-C2) that contained the first 21 amino acids of PSG11w COOH domain or mutant (PSG11w-C3) that contained a deletion of hydrophobic residues 372-392 in the PSG11w COOH domain remained largely in cells. In contrast, the PSG11w-C1 mutant which contained the first 12 residues of the PSG11w COOH domain became a secretory protein. Studies of PSG synthesis and processing in the presence of Brefeldin A, a drug that impedes protein transport from endoplasmic reticulum to the Golgi system, showed that PSG11w resided and degraded in the endoplasmic reticulum. The endoplasmic reticulum localization of PSG11w and the cell-associated mutant PSGs was further demonstrated by their sensitivity to endoglycosidase H and indirect immunofluorescence analysis.

Amino Acid Sequence↗

PubMedDate not supplied

An exploration of Pender's Health Promotion Model using LISREL.

A causal model based on Pender's (1987) Health Promotion Model was tested to evaluate Pender's hypothesis that demographic and biological characteristics affect health-promoting behaviors indirectly through three mediating cognitive-perceptual variables. A sample of 3,025 noninstitutionalized adults completed a telephone survey from which indicators of the conceptual variables were selected. Initial tests of the causal model using the LISREL 7 program indicated that the basic model did not fit the data. Therefore, the model was modified so that the exogenous variables--sex, age, income, martial status, education, and body mass index--had direct effects on select health-promoting behaviors. Further, the variables of self-actualization and interpersonal support were required to share common indicators as were health responsibility and interpersonal support. Though the modified model fit the data, little of the variance in health-promoting behaviors was explained, since all significant effects were weak.

Adult↗

PubMed1997

Phylogenetic analysis of the evolution of lactose digestion in adults.

In most of the world's population the ability to digest lactose declines sharply after infancy. High lactose digestion capacity in adults is common only in populations of European and circum-Mediterranean origin and is thought to be an evolutionary adaptation to millennia of drinking milk from domestic livestock. Milk can also be consumed in a processed form, such as cheese or soured milk, which has a reduced lactose content. Two other selective pressures for drinking fresh milk with a high lactose content have been proposed: promotion of calcium uptake in high-latitude populations prone to vitamin-D deficiency and maintainance of water and electrolytes in the body in highly and environments. These three hypotheses are all supported by the geographic distribution of high lactose digestion capacity in adults. However, the relationships between environmental variables and adult lactose digestion capacity are highly confounded by the shared ancestry of many populations whose lactose digestion capacity has been tested. The three hypotheses for the evolution of high adult lactose digestion capacity are tested here using a comparative method of analysis that takes the problem of phylogenetic confounding into account. This analysis supports the hypothesis that high adult lactose digestion capacity is an adaptation to dairying but does not support the hypotheses that lactose digestion capacity is additionally selected for either at high latitudes or in highly arid environments. Furthermore, methods using maximum likelihood are used to show that the evolution of milking preceded the evolution of high lactose digestion.

Adult↗

PubMed1997

Seventy-five nuclear DNA polymorphisms in an Italian sample: a comparative worldwide study.

A well defined Italian sample from Trino Vercellese (Northern Italy) is analysed for 75 nuclear DNA RFLPs. It represents the only European sample [Matullo et al 1994] which is unmixed in a comparative study of eight populations from four continents [Bowcock et al 1991a; Lin et al 1994]. Genetic substructure of this sample has been investigated by allele sharing distances and no bias or higher homogeneity is shown. Genetic variability between populations was measured by the FST statistics (average FST was 0.138 +/- 0.086). Average heterozygosity for eight populations was 0.312 +/- 0.069. Genetic distances were evaluated between pairs of populations. Phylogenetic trees were reconstructed and principal component analysis performed. Particular attention has been given to the genetic relationship between our sample and the mixed-Caucasoid sample: 14 out of 75 markers show statistically significant frequency differences (P < 0.05), 5 of which are significant at a probability level < 1%: GH/Bg1II (Lower system), D7S1/HindIII, D17S71/MspI, EPB3/PstI, HLA-DQA. Hypotheses on admixed origin of Europeans has been discussed.

Biological Evolution↗

PubMed1994

A surface epitope undergoing high-frequency phase variation is shared by Mycoplasma gallisepticum and Mycoplasma bovis.

We have recently reported that three distinct size- and phase-variable surface lipoproteins (Vsps) of the bovine pathogen Mycoplasma bovis possess a common epitope recognized by monoclonal antibody 1E5. In the present study, we show that this epitope is also present on a size-variant protein (PvpA) of the avian pathogen Mycoplasma gallisepticum. Application of monoclonal antibody 1E5 in Western immunoblot analysis of Triton X-114 phase-fractionated proteins and in colony immunoblots, as well as in trypsin and carboxypeptidase digestion experiments, has demonstrated that (i) PvpA is an integral membrane protein with a free C terminus, (ii) the shared epitope is surface exposed, and (iii) PvpA is subjected to high-frequency phase variation in expression. By using serum antibodies from M. gallisepticum-infected chickens, we were able to demonstrate the immunogenic nature of PvpA and identify three additional highly immunogenic Triton X-114 phase proteins (p67, p72, and p75) also undergoing high-frequency phase variation spontaneously and independently. Metabolic labeling experiments with [14C]palmitate and [14C]oleate revealed that PvpA, in contrast to p67, p72, and p75, is not lipid modified. Southern blot hybridization with restriction fragments carrying the pvpA gene of M. gallisepticum or the vspA gene of M. bovis against digested genomic DNA of the two Mycoplasma species indicated the absence of genetic relatedness between the pvpA and vspA genes. The apparent complexity of the antigenic variation phenomenon in M. gallisepticum is discussed.

Animals↗

PubMed2003

Sharing prescription medication among teenage girls: potential danger to unplanned/undiagnosed pregnancies.

OBJECTIVE: The objective of this study was to determine how often children and adolescents share prescription medications and, because of teratogenic concerns, assess specific reasons why girls might engage in medication-sharing behaviors. METHODS: Data were collected as part of Youthstyles, a mail survey of children and adolescents 9 through 18 years of age (764 girls and 804 boys) about health issues, attitudinal variables, and media preferences. Information collected by the survey included the respondent's history of borrowing or sharing prescription medications, the frequency with which sharing occurred, the reasons why medications might be borrowed or shared, and who influences their decisions to borrow or share medication. RESULTS: A total of 20.1% of girls and 13.4% of boys reported ever borrowing or sharing medications. Of the girls surveyed, 15.7% reported borrowing prescription medications from others, and 14.5% reported sharing their prescription medication with someone else. The reported likelihood of sharing increased with age. Medication sharing or borrowing was not a "one time only" emergency use for many: 7.3% of girls 15 through 18 years of age had shared medications >3 times. Reasons that girls gave for why they would share medications included having a prescription for the same medicine (40.2%), getting the medication from a family member (33.4%), having the same problem as the person who had the medication (29%), or wanting something strong for pimples or oily skin (10.5%). CONCLUSIONS: Medication sharing is relatively common among children and adolescents and is more common among girls than boys. An adolescent who receives a medication via sharing does not receive the appropriate information about its actions and possible negative interactions with other medications or any other associated risks. Sharing potentially teratogenic drugs is of special concern. Many barriers exist to communicating the risk about teratogenic drugs to women and girls, particularly if they are not planning a pregnancy or are unaware that they are already pregnant. These findings suggest the need for basic research on issues related to the dangers of medication sharing and teratogenic risks, as well as the development of successful approaches to communicate these risks.

Adolescent↗

PubMed1989

Antimitochondrial antibodies in primary biliary cirrhosis recognize both specific peptides and shared epitopes of the M2 family of antigens.

Sera from patients with primary biliary cirrhosis exhibit variable autoantibody reactivity against mitochondria, the commonest antigen (designated M2) including three structures of approximate M.W. 70, 50 and 40 kD. The nature of these antigens has only recently been established; the 70 and 50 kD are the transacetylase E2 and component X, respectively, of the pyruvate dehydrogenase complex and are distinct polypeptides. We have demonstrated, by immunoblotting, elution and rebinding of antibodies, unequivocal cross-reactivity between the major bands of the M2 antigen. In addition, cross-reactivity has been shown between antibodies binding to each of the three M2 bands of mitochondria and two major antigenic bands of both Gram-negative and Gram-positive bacteria. Conversely, antibodies eluted from these two bands of Escherichia coli were found to bind all three M2 bands of mitochondria. These results suggest that the antibodies of primary biliary cirrhosis contain both peptide-specific and cross-reacting antibodies, the latter recognizing a common "M2 epitope" that might include nonprotein components of the peptides. However, direct and competitive enzyme-linked immunosorbent assays failed to implicate the coenzyme of the pyruvate dehydrogenase complex, lipoic acid or its amide, as the common antigenic moiety.

Autoantibodies↗

PubMedDate not supplied

[Color perception in twins].

The classical twin method was used to examine the genotype--phenotype relationship in color vision. Suprathreshold color differences were assessed by 5 pairs of monozygotic (MZ) and 3 pairs of dizygotic (DZ) twins. The control group included 3 unrelated normal trichromats, a non-twin sibling pair, and a previously diagnosed deuteranomal. Concordance rates were calculated by Spearman's correlation coefficients (rs) and Procrustean distances (gl) between the reconstructed color spaces for each related pair of observers. For 4 pairs of the MZ twins, the rs values were comparable to intraindividual variability in the control normal trichromat; they were significantly higher (0.94-0.97) than those for the DZ twins and siblings (0.72-0.82). The gl values for the MZ twins (0.008-0.029) were lower than for the DZ twins (0.073-0.079) and siblings (0.053). The high concordance between each pair of the MZ twins suggests that their shared photopigment genome constrains a contribution of possible individual variations in nongenetic factors to variability of their color spaces. Lower concordance rates in the DZ twins and siblings can be attributed to differences in the inherited arrays of photopigment genes. Contributions to intrapair variation in color spaces of twins from cognitive factors such as perceptual-cognitive color categorization and decision-process variability are discussed.

Adolescent↗

PubMed2003

High-density lipoprotein concentrations relate to the clinical course of HIV viral load in patients undergoing antiretroviral therapy.

OBJECTIVE: To determine whether levels of HDL are associated with viral load response in HIV-treated patients, and to seek an explanation based on amino acid sequence similarity between the key apolipoprotein A1 and HIV proteins concerned in viral replication. DESIGN: The major HDL lipoprotein is apolipoprotein A1, which is able to inhibit HIV-induced syncytium formation. This retrospective clinical study assessed the relationship between the response to antiretroviral treatment (time of undetectable viral load/duration of viral suppression below the limit of detection) and HDL-cholesterol levels on commencing antiretroviral treatment. PATIENTS AND METHODS: HIV-treated patients with undetectable HIV viral loads were followed every 3 months for 36 months. We measured total cholesterol, HDL-cholesterol, triglycerides, previous responses to antiretroviral treatment, opportunistic infections, sex and age. These variables were assessed in relation to the time of undetectable viral load until viral rebound. Amino acid sequence alignment was performed with HIV proteins and apolipoprotein A1 to detect shared similarity. RESULTS: The Cox proportional hazards model showed a significant association between HDL-cholesterol and the time of undetectable viral load. The other variables studied were not associated. There was 30% sequence similarity in an area of 50 amino acids shared between apolipoprotein A1 and p17 Gag-HIV protein. CONCLUSION: High levels of HDL-cholesterol are associated with a better viral response in treated HIV patients. This association could be related to the sequence similarity and structure homology between apolipoprotein A1 and p17 Gag-HIV protein, which raises the intriguing clinical possibility that inducing an increase in HDL could assist HIV therapy.

Adult↗

PubMed2006

Quantitative dysmorphology assessment in Fabry disease.

PURPOSE: 1) To identify morphometric characteristics in hemizygous patients with Fabry disease a treatable lysosomal storage disorder caused by the deficiency of alpha-galactosidase A where morphological abnormalities have occasionally been mentioned, but have never been investigated systematically. 2) To devise a quantitative method to evaluate dysmorphic abnormalities in Fabry disease. METHOD: Cross-sectional, single center, independent dysmorphology assessment by a panel of three clinical geneticists, based on standardized medical photography. POPULATION: consecutive hemizygous patients with Fabry disease (N = 38) unselected for the features assessed, mean age 38 +/- 10.8 years (range: 10-60), recruited for neuropathic pain into enzyme replacement therapy trials. RESULTS: The following dysmorphic features were identified (in order of descending frequency): periorbital fullness, prominent lobules of the ears, bushy eyebrows, recessed forehead, pronounced nasal angle, generous nose/bulbous nasal tip, prominent supraorbital ridges, shallow midface, full lips, prominent nasal bridge, broad alar base, coarse features, posteriorly rotated ears, and prognathism. Extremity features included broad fingertips, short fingers, prominent superficial vessels of hands, 5 digit brachydactyly, and 5 digit clinodactyly. Narrow anterior-posterior chest diameter was noted. Ten core features were statistically defined. Cronbach's alpha measuring internal consistency was 0.62. Light's kappa for global inter-rater variability was 0.26 while Cohen's kappa allowing pair-wise rater comparison varied between 0.08-0.48. CONCLUSIONS: Patients with Fabry disease share common morphological characteristics of the face, trunk, and extremities. Some of these features are subtle as documented by the inter-rater variability. Awareness of these features may facilitate the diagnosis of patients with Fabry disease, and identification of affected family members.

Adolescent↗

PubMed2000

Adoption of alternative financing strategies to increase the diffusion of picture archiving and communication systems into the radiology marketplace.

The objective of the study was to evaluate current marketplace conditions and strategies employed by major picture archiving and communication systems (PACS) vendors in the creation of alternative financing strategies, to enhance the diffusion of filmless imaging. Data were collected from the major PACS vendors in the forms of survey questionnaires and review of existing leases. Topics evaluated in the survey included current financing options available, foreseeable changes in PACS financing, role of third-party financiers, and creation of risk-sharing arrangements. Generic leases were also reviewed evaluating the presence or absence of several key variables including technology obsolescence protection, hardware/software upgrades, end-of-term options, determination of fair market value, functionality/acceptance testing, uptime guarantees, and workflow management consulting. Eight of the 10 PACS vendors surveyed participated in the data collection. The vast majority of current PACS implementations (60% to 90%) occur through direct purchase, with conventional leasing (operating or capital) accounting for only 5% to 30% of PACS installations. The majority of respondents view fee-for-lease arrangements and other forms of risk sharing as increasing importance for future PACS financing. The specific targets for such risk-sharing arrangements consist of small hospital and privately owned imaging centers. Leases currently offered range in duration from 3 to 5 years and frequently offer technology obsolescence protection with upgrades, multiple end-of-term options, and some form of acceptance testing. A number of important variables frequently omitted from leases include uptime guarantees, flexibility in changing financing or vendors, and incorporation of expected productivity/operational efficiency gains. As vendors strive to increase the penetration of PACS into the radiology marketplace, there will be a shift from conventional financing (loan or purchase) to leasing. Fee-for-use leasing and other forms of risk sharing have the greatest potential in smaller hospitals, which do not have the financial resources to pursue conventional financing options. Potential PACS customers must be cautious when entering into these alternative financing strategies, to ensure that appropriate safeguards are incorporated, in order to minimize downside risk.

Cost Sharing↗

PubMed1993

Immunoglobulin variable region sequences of two human monoclonal antibodies directed to an onco-developmental carbohydrate antigen, lactotetraosylceramide (LcOse4Cer).

A human monoclonal antibody, 11-50, was generated and was shown to recognize an onco-developmental carbohydrate antigen, LcOse4Cer. The isotype of this antibody was IgM, lambda, similar to the previously known human anti-LcOse4 antibodies, such as IgMWOO and HMST-1. We raised a murine anti-idiotypic antibody G3 (IgG1, kappa) against 11-50, and tested its reactivity towards the affinity purified human polyclonal anti-LcOse4 antibodies prepared from pooled human sera using a Gal beta 1-->3GlcNAc beta-immobilized column. The results indicated that at least a part of the human polyclonal anti-LcOse4 antibodies shared the G3 idiotype with 11-50. We further analyzed the sequence of variable regions of the two anti-LcOse4 antibodies, 11-50 and HMST-1. Sequence analysis of the heavy chain variable regions indicated that the VH regions of these two antibodies were highly homologous to each other (93.5% at the nucleic acid level), and these antibodies utilized the germline genes VH1.9III and hv3005f3 as the VH segments, which are closely related germline genes of the VHIII family. It was noted that these germline VH genes are frequently utilized in fetal B cells. The JH region of both antibodies was encoded by the JH4 gene. For the light chain, the V lambda segments of the two antibodies were 96.3% homologous to each other at the nucleic acid level. The V lambda segments of both antibodies showed the highest homology to the rearranged V lambda gene called V lambda II.DS among reported V lambda genes, while the exact germline V lambda genes encoding the two antibodies were not yet registered in available sequence databanks. The amino acid sequences of the J lambda segments of both antibodies were identical. These results indicate that the two human antibodies recognizing the onco-developmental carbohydrate antigen Lc4 are encoded by the same or very homologous germline genes.

Amino Acid Sequence↗

PubMed2004

Variable response to long-term corticosteroid therapy in chronic beryllium disease.

OBJECTIVES: Chronic beryllium disease (CBD) shares many of its characteristics with sarcoidosis and is often treated with corticosteroids. There is limited available literature regarding the effect of long-term corticosteroid therapy on the natural history of CBD. METHODS AND MATERIALS: We conducted an observational retrospective study of six patients with CBD who received prolonged corticosteroid treatment with a mean pulmonary function test follow-up period of 10.1 years. Five of the six patients were exposed to beryllium at the same workplace. The diagnosis in four of the six cases was confirmed by a positive beryllium lymphocyte proliferation test result on blood or BAL fluid. Periodic pulmonary function tests were analyzed in relation to removal from beryllium exposure and treatment with corticosteroids. MEASUREMENTS AND RESULTS: Two broad patterns of response were noted in these patients. The first pattern seen in two patients showed no improvement in FVC or diffusion capacity of the lung for carbon monoxide (Dlco) with corticosteroids. However, a significant improvement in these parameters was noted on cessation of beryllium exposure in one of the two patients. The second pattern showed an initial improvement in FVC and Dlco with corticosteroids, which was not sustained. An improvement was noted on stopping beryllium exposure. CONCLUSIONS: The response to long-term corticosteroids in CBD, quite like that in sarcoidosis, is variable. Significant lung function improvement may be seen following cessation of beryllium exposure.

Adult↗

PubMed2026

A quantitative coordinate system for developmental dynamics.

Quantitative comparison of morphogenesis across individuals remains a fundamental challenge, as developing embryos vary in shape, orientation and developmental tempo. Moreover, real-time three-dimensional imaging generates large, heterogeneous four-dimensional datasets that are difficult to directly align. As a result, developmental variability is typically described qualitatively rather than measured. Here we introduce STERN, a quantitative framework that learns continuous spatiotemporal representations of morphogenesis directly from in vivo 4D imaging data. By embedding embryos into a shared spatiotemporal space, STERN defines a quantitative developmental coordinate system that enables direct comparison of developmental trajectories across individuals without requiring explicit registration or staging. Applied to mouse embryogenesis, STERN reveals that embryos follow conserved developmental trajectories while progressing at distinct temporal rates, providing a quantitative measure of developmental heterochrony. Extending this framework to zebrafish neural crest light-sheet timelapse imaging, we further show that developmental order is preserved across distinct imaging views even with altered anatomical coverage, supporting the generality of the learned representation across vertebrate imaging contexts. Finally, in developing mouse hearts, where morphogenesis proceeds through subtle and continuously evolving structural changes, STERN resolves fine-scale developmental dynamics at minute-scale temporal resolution that are difficult to localize reproducibly using human experts or general-purpose multimodal AI. Together, these results establish a shared quantitative coordinate system for morphogenesis, in which developmental trajectories become directly comparable across individuals and developmental variability becomes a measurable property.

Journal Article↗

PubMed2003

A meta-analysis of estimated genetic and environmental effects on smoking behavior in male and female adult twins.

BACKGROUND: Numerous twin studies on smoking behavior have shown that genetic and environmental factors play significant and approximately equal roles in the determination of smoking initiation (SI) and smoking persistence (SP). However, estimates of heritability (h2), shared (c2) and unique environmental effects (e2) from the literature display considerable variability for SI and SP, due most probably to differences in statistical analysis models, age, gender, sample size, origin of cohorts and measurement of smoking behavior. METHODS: A systematic literature search identified six studies for SI and 10 studies for SP. Data from these studies were obtained and re-analysed by meta-analytical techniques. RESULTS: For SI, our results indicate that the parameters h2, c2 and e2 are (mean +/- SEM): 0.37 +/- 0.04, 0.49 +/- 0.04 and 0.17 +/- 0.03 in male adults, and 0.55 +/- 0.04, 0.24 +/- 0.06 and 0.16 +/- 0.01 in female adults, respectively. These values were weighted by a combination of original estimates of variance from studies reporting variances plus estimated variances from studies where variances were not reported (called the combined variance method). Using the same approach for SP, we found that the parameters h2, c2 and e2 weighted by the combined variance method for the phenotype are (mean +/- SEM): 0.59 +/- 0.02, 0.08 +/- 0.04 and 0.37 +/- 0.03 in male adults, and 0.46 +/- 0.12, 0.28 +/- 0.08 and 0.24 +/- 0.07 in female adults, respectively. CONCLUSIONS: Our results indicate that genetic factors play a more significant role for SI but a less significant role for SP in female adults compared to male adults. Significant gender difference was also detected in shared environmental factors for SI and SP. However, no significant gender difference was detected for e2 for either phenotype. These findings suggest that genetic and environmental factors may contribute differently to the determination of smoking initiation and persistence in male and female smokers.

Adult↗

PubMed2004

Comparative genomics of the T4-Like Escherichia coli phage JS98: implications for the evolution of T4 phages.

About 130 kb of sequence information was obtained from the coliphage JS98 isolated from the stool of a pediatric diarrhea patient in Bangladesh. The DNA shared up to 81% base pair identity with phage T4. The most conserved regions between JS98 and T4 were the structural genes, but their degree of conservation was not uniform. The head genes showed the highest sequence conservation, followed by the tail, baseplate, and tail fiber genes. Many tail fiber genes shared only protein sequence identity. Except for the insertion of endonuclease genes in T4 and gene 24 duplication in JS98, the structural gene maps of the two phages were colinear. The receptor-recognizing tail fiber proteins gp37 and gp38 were only distantly related to T4, but shared up to 83% amino acid identity to other T6-like phages, suggesting lateral gene transfer. A greater degree of variability was seen between JS98 and T4 over DNA replication and DNA transaction genes. While most of these genes came in the same order and shared up to 76% protein sequence identity, a few rearrangements, insertions, and replacements of genes were observed. Many putative gene insertions in the DNA replication module of T4 were flanked by intron-related endonuclease genes, suggesting mobile DNA elements. A hotspot of genome diversification was located downstream of the DNA polymerase gene 43 and the DNA binding gene 32. Comparative genomics of 100-kb genome sequence revealed that T4-like phages diversify more by the accumulation of point mutations and occasional gene duplication events than by modular exchanges.

Bacteriophage T4↗

PubMed1980

Immunoglobulin V/J recombination is accompanied by deletion of joining site and variable region segments.

A site-specific recombination event is responsible for the somatic activation of immunoglobulin genes and for generating a major share of immunoglobulin gene diversity. Although several possible mechanisms can be proposed to account for this process, recombinatio accompanied by deletion is a particularly attractive mechanism because it might utilize inverted repeat sequences noted on the 3' side of all variable regions and on the 5' side of all joining site segments thus far studied. Testing this model is complicated by the fact that antibody cells are at least diploid and gene segments on the inactive chromosome can obscure deletions occurring within the active gene. Accordingly, we have screened several immunoglobulin-producing plasmacytoma lines to select those in which both chromosomes are rearranged. By using appropriate cell lines and variable and joining region probes in in situ hybridization experiments, we show that recombination is accompanied by the deletion of both variable and joining region genes. These experiments also allow us to map the site of V/J recombination of several active immunoglobulin genes and suggest an order and orientation for variable, joining, and constant region sequences.

Animals↗

PubMed1993

Prevalence of post partum depression--or is it post-puerperium depression?

In a longitudinal study, the prevalence of post partum depression was investigated in 293 women. They were assessed during gestation at 32 weeks, and consecutively after parturition with an interval of six weeks from four weeks until 34 weeks' post partum. The prevalence of post partum depression (RDC) varied between seven and 14%, with a peak at ten weeks' post partum. It was found that women were depressed significantly more often at ten weeks' post partum compared with pregnancy, the first post partum weeks and the later post partum period. This finding suggests that it is not directly after parturition that women are more prone to depression. The relationship between variables such as blues, parity, PMS and depression showed that at different assessments in the post partum period different women are depressed, women who do not necessarily share the same characteristics. This finding may explain why in some studies a relationship was found between certain kinds of variables and post partum depression while in others not. PMS was found to be significantly related to post partum depression only at the time of the women resumed menstruation. It is suggested that screening on post partum depression partly involves screening on depressive symptoms related to PMS.

Adult↗