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Biomedical subjects

J M Schneider

Publications and source records attributed to J M Schneider.

At least 19 recordsLinked to original sources
PubMed2006

A Bayesian belief network for quality assessment: application to employment officer support.

BACKGROUND: 'Supported' employment stipulates that disabled people should have real jobs for real pay. This paper models kinds of supported employment, assesses how the support and placement features affect its outcomes and its quality from the perspective of the employees, and provides a dynamic model to help explore what types of interventions might promote greater social inclusion for people with learning and other disabilities. METHOD: Bayesian belief networks (BBNs) provide the general framework for modelling the relationships between the variables and features of interest. The structure, probabilistic specification and quality indicators were elicited from project advisory groups, including people with learning disability, and took into account a pilot survey of 30 individuals. A subsequent survey of 1,461 supported employees was used to update the model and to provide actual assessments of quality of placement. RESULTS: We present the BBN methodology in some detail, as novel to this discipline. We show how the model was constructed, and its implications for supported employment. We derive indices for quality of placement, taking into account the views of clients. We show how survey and individual results can be used to update the model. Use of the model suggests that quality of placement is, on average, relatively high, with small differences between groups with differing primary disability. CONCLUSIONS: The BBN is the appropriate methodology to model complex relationships and interventions for problems such as these. The model developed in this study can be used to assess and improve the fit between people and jobs, both at the individual level and for groups of employees, and can take into account different kinds of quality for different stakeholders.

Adult↗
PubMed2002

The asymptotic leading term of anisotropic small-angle scattering intensities. II. Non-convex particles.

For anisotropic particulate samples with scattering contrast (delta n)(2), the leading asymptotic term of the scattering intensity, along a direction q (q/q) of reciprocal space, is [4 pi(2)(delta n)(2)/q(4)]sigmaj [1/kappaG.j(+/-q)]. Here, kappaG.j(+/-q)denotes the Gaussian curvature value at the points (labelled by j) of the interphase surface where the normal is either parallel or antiparallel to q. If the Gaussian curvature vanishes at, say, the jth of these points, the corresponding contribution takes the form Cj/qalpha with 2< or = alphaj<4, Cj and alphaj being determined by the local behaviour of the surface. However, the intensity detected by a counter pixel, with opening solid angle deltaomega(q0) along (mean) direction q0, asymptotically still behaves as 4pi(2) (delta n)(2)(deltaomega(q0))/q(4), where S(deltaomega(q0)) is the area of that part of the interface that has its normals inside deltaomega(q0).

Journal Article↗
PubMed2001

Collaboration to implement smoking cessation guidelines during the childbirth continuum.

BACKGROUND: Smoking during pregnancy has been linked with such negative outcomes as increased risk for spontaneous abortions, low birth weight, and perinatal and neonatal mortality. In spring 1998 three leading health care systems in San Diego initiated the Trilateral Partnership ("the Partnership"), whose mission is to improve the health and well-being of children. The Partnership chose tobacco control in pregnant women and their families as its first initiative. PROGRAM COMPONENTS-YEAR ONE (1999): Three interventions were developed: intervention by the prenatal care provider, initiation of a referral process to telephone counseling for pregnant women, and intervention for women reporting spontaneously quitting smoking. To date, 83% of the more-than 20,000 women who have been seen in prenatal screening in 28 months counted themselves as nonsmokers. Eleven percent of the women reported they independently stopped smoking once they learned they were pregnant. Six percent reported that they were still smoking. Twenty-three percent of the women reported living in a household with other smokers. PROGRAM COMPONENTS-YEAR TWO (2000): Activity focused on continuing the previous components, hospital intervention for all new mothers at the time of delivery, pediatric intervention at the newborn's visits at 2 and 6 months of age, and development and refinement of a telephone protocol for new parents. ELEMENTS OF SUCCESS: The noncontroversial topic of encouraging smoking cessation during pregnancy was one that enhanced immediate buy-in by most individuals contacted to support and engage in the program. Strong commitment and financial support from three health care systems opened doors for the Smoke-Free Families staff and increased the program's visibility in the community.

Adult↗
PubMed2000

Female control of paternity in the sexually cannibalistic spider Argiope keyserlingi.

Sexual conflict theory predicts an antagonistic coevolution, with each sex evolving adaptations and counter-adaptations to overcome a temporary dominance of the other sex over the control of paternity. Polyandry allows sexual selection to operate after mating has commenced, with male and female interests competing for control of fertilization. There are numerous examples of male control of paternity, but few studies have unambiguously revealed female control. Attributing variance in paternity to females is often difficult since male and female influences cannot be separated unambiguously. However, we show that polyandrous female orb-web spiders Argiope keserlingi (Arancidae) control the paternity of their offspring by adjusting the timing of sexual cannibalism. Our experiments reveal that females copulating with relatively smaller males delay sexual cannibalism, thereby prolonging the duration of copulation, and that these males consequently fertilize relatively more eggs.

Animals↗
PubMed2000

Chronic disease self-management: improving health outcomes.

Chronic disease has become pandemic in the United States, and estimates are that it will affect 148 million people by the year 2030. Patients with chronic illnesses cost the health care system over three times more than individuals without chronic conditions. The US Department of Veterans' Affairs (VA) Sunshine HealthCare Network, composed of VA health care facilities in Florida and Puerto Rico, recognized that the needs of its increasing number of veterans with chronic diseases were unmet by traditional medical interventions. The Network implemented a chronic disease self-management pilot program to evaluate its value for the veteran population. Results of the pilot indicate that this program will make a positive, lasting change in the health status and quality of life for veterans with chronic disease.

Adult↗
PubMed1997

Pregnancies in a patient with congenital absence of prothrombin activity: case report.

Congenital hypoprothrombinemias are very rare, inherited disorders in which factor II (prothrombin) levels and/or activity are extremely low or absent. We report eight pregnancies in a patient with this disorder. Obstetric complications attributed to the coagulation disturbance included first-trimester bleeding in each pregnancy, miscarriage in four of the pregnancies, spontaneous maternal subarachnoid hemorrhage in one, and postpartum hemorrhage in one of four term pregnancies despite administration of clotting factor concentrate. The management of pregnancy in congenital hypoprothrombinemia, and issues of coagulation factor replacement, are discussed.

Abortion, Spontaneous↗
PubMed1995

Severe preeclampsia with fulminant and extreme elevation of aspartate aminotransferase and lactate dehydrogenase levels: high risk for maternal death.

We report a subgroup of patients with fulminant hemolysis, elevated liver enzymes, low platelet count (HELLP) syndrome, manifesting extreme elevation of aspartate aminotransferase (AST; SGOT) and lactate dehydrogenase (LDH) levels and abnormal mental status. These gravidas are at high risk for mortality. Only four patients treated by the authors over a 10-year period have had AST more than 2000 IU/L and LDH more than 3000 IU/L in the HELLP syndrome. This report is based on retrospective chart review. All patients manifested disordered mental status, jaundice, intense hemolysis, and extreme hypertension. One patient had developed multiple organ system failure, was moribund at initial perinatal consultation, and died. The three others were treated with aggressive afterload reduction and plasma infusion or plasmapheresis; two survived. Fulminant HELLP syndrome occurs rarely, but marks a group of patients at high risk for mortality. Optimal therapy is unclear; early intervention, including afterload reduction, volume expansion, and consideration of plasma infusions or plasmapheresis, is recommended.

Adult↗
PubMed1988

Effects of bepridil on calcium release from rat heart mitochondria.

Bepridil at concentrations above 10 microM, and at pH 7.2 stimulates calcium release from rat heart mitochondria. However this action is different from that of ClCCP, an uncoupler of oxidative phosphorylations, since it is ruthenium red insensitive. At lower concentrations bepridil may inhibit the Na-induced calcium release. The effects of bepridil depend on the pH and indicate that the protonated form of the drug is more efficient on calcium release than the basic form.

Animals↗
PubMed1985

Redistribution of creatine kinase isoenzymes in chronically overloaded myocardium.

Chronic overload due to an experimental abdominal aortic stenosis in rats causes hypertrophy of ventricles and a parallel increase of the MB and BB isoforms of creatine kinase (CK) in cardiac tissue. The CK isoenzyme profile was determined using a new two-step method combining anion exchange chromatography and electrophoresis. In overloaded ventricles a shift was observed from the MM isoform which decreased (from 407 +/- 10 mumol X min-1 X g-1 ww in sham-operated to 370 +/- 0.13, in the overloaded group, p less than 0.05) towards the MB and BB forms whose activity was enhanced (from 56 +/- 4 and 6.5 +/- 0.7 to 77 +/- 6 and 10.1 +/- 1.2, respectively, p less than 0.02). These modifications were more pronounced (318 +/- 15, 83 +/- 15 and 15.1 +/- 2.5, for the MM, MB and BB forms respectively, p less than 0.01) in rats having a very marked hypertrophy and whose ventricular/body weight ratio (expressed in mg of ventricles per g) was above 3. Moreover this ratio correlates both with the amount of the MB form (r = 0.32, p less than 0.05) and with the percentage of the B monomer (r = 0.51, p less than 0.01). This shift, like that previously described for lactate dehydrogenase and myosin, favoured the fetal form and this supports the hypothesis that overloaded myocytes improve their efficiency by expressing some of the isoforms normally present in the fetus.

Animals↗
PubMed1984

lac Repressor cysteine-140 reacts selectively with a fluorescent probe bound to the core-headpiece interface.

The fluorescent probe N-[(iodoacetyl)amino]-ethyl]-5-naphthylamine-1-sulfonate (I-AEDANS) reacts selectively with Cys-140 of the lac repressor. The reasons for this selectivity were investigated. The ability of 8-anilino-1-naphthalenesulfonate and 5,5'-bis(8-anilino-1-naphthalene-sulfonate) to bind noncovalently to the interface between the core and headpiece regions of the repressor suggested that I-AEDANS might also bind to this interface and then react intramolecularly with Cys-140 nearby. Two observations strongly support this model. (1) The selectivity for Cys-140 was lost when the headpiece regions were removed from the repressor. The rate of reaction with Cys-140 relative to Cys-107 in the repressor was 13.5 +/- 1.4, from trypsin digestions of labeled repressor. This ratio decreased to 2.1 +/- 1.0 for the core protein. (2) Iodoacetamide, which lacks the naphthylaminesulfonate portion of I-AEDANS, showed little selectivity for Cys-140 in either the repressor or the core. Nonreactive analogues of I-AEDANS did not alter the reaction of I-AEDANS with the repressor, presumably because they bound too weakly. Decreasing the ionic strength from 0.61 M to 56 mM decreased the selectivity of I-AEDANS for Cys-140 in the repressor, suggesting that I-AEDANS is not bound to the repressor by ionic interactions. Decreasing the pH from 8.5 to 7.5 increased the selectivity for Cys-140 only slightly. Fluorescent probes attached to Cys-140 appear to be ideally located to report motions of the headpieces , relative to the core, that attend DNA binding.

Cysteine↗
PubMed1984

Effects of bepridil on Ca2+ uptake by cardiac mitochondria.

Isolated rat heart mitochondria accumulate large amounts of Ca2+ at the expense of respiration-linked energy or of that provided by the hydrolysis of ATP by the mitochondrial ATPase. At concentrations below 10 microM bepridil has no effect on the first mechanism but inhibits the second. At higher concentrations bepridil depresses both. At low concentrations bepridil decreases proton influx into mitochondria in ADP-stimulated respiration while it has no effect on proton ejection in Ca2+-stimulated respiration. A preliminary study shows that bepridil inhibits ATP hydrolysis linked to Ca2+ absorption by mitochondria. The calcium antagonists verapamil, nifedipine and diltiazem exhibit none of these effects.

Adenosine Triphosphatases↗
PubMed1984

Demographic components of gene frequency change in free-ranging macaques on Cayo Santiago.

Gene frequency profiles from January 1973 to January 1977 for three polymorphic loci were examined in Cayo Santiago rhesus social groups. The effects of demographic components (i.e., births, deaths, immigrations, emigrations, and group fission and fusion) on total change in gene frequencies are assessed. Allelic frequencies at the carbonic anhydrase II, 6-phosphogluconate dehydrogenase, and transferrin loci were analyzed in four social groups. In the two groups that underwent fission and fusion during the study period, the timing of these processes was related to the largest short-term changes in gene frequences. However, immigration and emigration had the greatest effect on total change in gene frequency in all groups during the study period. The relative importance of births and deaths in producing gene frequency change varied among the social groups. These results suggest that the relative importance of the demographic components of gene frequency change in primate populations is determined by behavioral patterns and ecological conditions specific to the population considered.

Animals↗
PubMed1983

Thrombotic thrombocytopenic purpura: report of fourteen cases--occurrence during pregnancy and response to plasma exchange.

Thrombotic thrombocytopenic purpura (TTP), a syndrome of diverse etiology probably related to factors regulating platelet-vessel wall interaction, is predominantly a disorder of women. We report our experience with 14 patients in an 11-year period. Thirteen were female and aged between 25-69 years. Four were postmenopausal, and of the nine premenopausal women three were pregnant, one was immediately postpartum, and three were taking estrogen-containing oral contraceptives. A review of the literature confirms the two to one female/male preponderance and that TTP is reported in 56 women who are pregnant or recently postpartum. While this association with possible hormonal events has been noted, it has previously received little comment. We stress the similarity between TTP and some occurrences of preeclamptic toxemia, and that this may suggest not only a common etiology but that therapeutic attempts should be similar. While no single therapeutic modality is universally successful, our experience is that plasma exchange is the most effective, with five of seven patients so-treated obtaining prolonged remission; four of five patients responded to splenectomy and corticosteroids, but one died of infection postoperatively. Five patients, including two treated exclusively with antiplatelet aggregating agents, died without achieving remission. The frequency of successful therapy is not changed by the concurrent pregnancy, but the fetal loss is high. There does seem to be an increased risk of recurrence of TTP in a subsequent pregnancy, and this might be considered when counseling premenopausal patients who have achieved remission of TTP.

Adrenal Cortex Hormones↗