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J Merrill

Publications and source records attributed to J Merrill.

At least 19 recordsLinked to original sources
PubMed2001

Family-based transmission disequilibrium test (TDT) and case-control association studies reveal surfactant protein A (SP-A) susceptibility alleles for respiratory distress syndrome (RDS) and possible race differences.

A key cause of respiratory distress syndrome (RDS) in the prematurely born infant is deficiency of pulmonary surfactant, a lipoprotein complex. Both low levels of surfactant protein A (SP-A) and SP-A alleles have been associated with RDS. Using the candidate gene approach, we performed family-based linkage studies to discern linkage of SP-A to RDS and identify SP-A susceptibility or protective alleles. Moreover, we performed case-control studies of whites and blacks to detect association between RDS and SP-A alleles. Transmission disequilibrium test (TDT) analysis revealed that the frequency of transmission (from parent to the offspring with RDS) of alleles 6A(2) and 1A(0) and of 1A(0)/6A(2) haplotype in RDS was increased, whereas transmission of alleles 1A(5) and 6A(4) and of haplotype 1A(5)/6A(4) was decreased. Extended TDT analysis further strengthened the observations made. The case-control studies showed that in whites or blacks with RDS the frequencies of specific genotypes, 1A(0) and 6A(2) or 1A(0), were increased, respectively, but the frequency of specific 6A(3) genotypes was increased in certain white subgroups and decreased in blacks. Regression analysis revealed gestational age (GA) and 6A(3) genotypes are significant factors in blacks with RDS. In whites with RDS, GA and antenatal steroids are important factors. The data together indicate linkage between SP-A and RDS; certain SP-A alleles/haplotypes are susceptibility (1A(0), 6A(2), 1A(0)/6A(2)) or protective (1A(5), 6A(4), 1A(5)/6A(4)) factors for RDS. Some differences between blacks and whites with regard to SP-A alleles may exist.

Alleles↗
PubMed2001

Enumeration of the public health workforce: developing a system.

Although it has been of interest to public health leaders, advocates, and policy planners for many years, decades have passed since the last organized count of public health workers. This article reports on methods used by the Columbia University School of Nursing, Center for Health Policy, to enumerate the public health workforce in 57 states and territories based on existing reports, summaries, and surveys. The complexity of public health workforce data is described and the scheme utilized to characterize the workforce using public agency categories is illustrated. The resulting "best current estimate" provokes many questions regarding future policy about a public health workforce database.

Data Collection↗
PubMed2001

The validity of self-reported cost events by substance abusers. Limits, liabilities, and future directions.

The following review considers data on the validity of self-reports in addict populations, and then it discusses (a) the types of cost-related questions and the assumptions underlying them that are useful to the evaluation of addictions treatment, (b) both internal and external sources of invalidity, (c) the limits on cost-related information that is gathered from administrative databases, (d) methods for assessing measure validity, and (e) the means for improving the validity of self-reports of cost events. With some important exceptions, addicts provide valid data about both medical and criminal cost events. Skilled socioeconomic researchers able to monetarize these events should be able to produce significant cost of illness, cost offset, cost-benefit, and cost-effectiveness research using self-report data.

Humans↗
PubMed2001

Dominant negative guard cell K+ channel mutants reduce inward-rectifying K+ currents and light-induced stomatal opening in arabidopsis.

Inward-rectifying potassium (K+(in)) channels in guard cells have been suggested to provide a pathway for K+ uptake into guard cells during stomatal opening. To test the proposed role of guard cell K+(in) channels in light-induced stomatal opening, transgenic Arabidopsis plants were generated that expressed dominant negative point mutations in the K+(in) channel subunit KAT1. Patch-clamp analyses with transgenic guard cells from independent lines showed that K+(in) current magnitudes were reduced by approximately 75% compared with vector-transformed controls at -180 mV, which resulted in reduction in light-induced stomatal opening by 38% to 45% compared with vector-transformed controls. Analyses of intracellular K+ content using both sodium hexanitrocobaltate (III) and elemental x-ray microanalyses showed that light-induced K+ uptake was also significantly reduced in guard cells of K+(in) channel depressor lines. These findings support the model that K+(in) channels contribute to K+ uptake during light-induced stomatal opening. Furthermore, transpirational water loss from leaves was reduced in the K+(in) channel depressor lines. Comparisons of guard cell K+(in) current magnitudes among four different transgenic lines with different K+(in) current magnitudes show the range of activities of K+(in) channels required for guard cell K+ uptake during light-induced stomatal opening.

Arabidopsis↗
PubMed1999

Prior treatment history and its impact on criminal recidivism.

This study examines the hypothesis that treatment is a cumulative process; that is, treatment success is best viewed in terms of the patient's entire treatment history, rather than the index treatment episode. Three-hundred and eight patients with a primary heroin addiction were studied for 2 years posttreatment. Using posttreatment arrests as the dependent variable, the effects of prior treatment were assessed. Those with six or more prior treatment episodes and who had been in treatment for 12 or more months during the most recent episode averaged only 0.2 arrests in the 2 years posttreatment, while those with no prior treatment, but 12 or more months in the recent treatment averaged 0.88 arrests. Logistic analysis found that each prior treatment reduced the probability of a posttreatment arrest by 25%. Based on a linear regression, patients with six or more treatments prior treatments averaged half the number of posttreatment arrests as someone with no treatments before the index episode.

Adult↗
PubMed1999

Changes in oxygenation with inhaled nitric oxide in severe bronchopulmonary dysplasia.

BACKGROUND: Severe bronchopulmonary dysplasia (BPD), which is associated with high mortality and morbidity, is thought to be the result of mechanical, inflammatory, and oxidant injury to the immature lung, and includes the development of pulmonary hypertension with vascular remodeling. METHODS: A phase II pilot study was conducted to determine the effect of inhaled nitric oxide (iNO) on oxygenation in severe BPD. This was an open-labeled, noncontrolled trial to evaluate safety and determine appropriate dosing for a future randomized controlled trial. Infants were eligible for enrollment if they were >/=4 weeks of age and ventilator dependent with a mean airway pressure of >/=10 cm H2O and an FIO2 of >/=0.45. Study infants received iNO (20 ppm) for 72 hours, and FIO2 was adjusted to maintain oxygen saturations of >92%. Infants who had a >/=15% reduction in FIO2 after 72 hours received prolonged treatment with low-dose iNO, weaning by 20% every 3 days as tolerated. FINDINGS: Sixteen preterm infants (23-29 weeks of gestation), age 1 to 7 months, were enrolled. Eleven of 16 infants had a significant increase in PaO2 after 1 hour of iNO (median change, 24 mm Hg; range, -15 to 59 mm Hg; P <.01), but there was no significant change in PaCO2. After 72 hours of iNO, 11 infants had >/=15% reduction in FIO2, and 7 of the 11 had >/=35% reduction (P <. 01). Among the 11 infants who responded to iNO after 72 hours, 10 had a sustained improvement in oxygenation throughout their course of treatment (duration, 8-90 days), and ventilator support could also be decreased. No adverse effects from iNO (increased methemoglobin, bleeding, or increased plasma 3-nitrotyrosine) were observed. Four of the 11 infants (36%) who responded to iNO ultimately weaned off mechanical ventilation and 4 died, whereas all the infants who failed to respond to iNO either died or continue to require mechanical ventilation. INTERPRETATION: We conclude that the use of low-dose iNO may improve oxygenation in some infants with severe BPD, allowing decreased FIO2 and ventilator support without evidence of adverse effects. Randomized clinical trials of low-dose iNO for BPD are warranted.

Administration, Inhalation↗
PubMed1998

Caring for terminally ill persons: comparative analysis of attitudes (thanatophobia) of practicing physicians, student nurses, and medical students.

To investigate why some caregivers desire to avoid patients with terminal illnesses, a thanatophobia scale assessing caregivers' uncomfortable feelings and sense of helplessness was developed and evaluated among practicing physicians and student nurses and medical students. As a group, student nurses scored lower on the thanatophobia scale than practicing physicians and medical students. Higher scores on intolerance to clinical uncertainty were associated with higher thanatophobia scores in all groups. Scores for depressed mood, decreased sensitivity, and Machiavellianism were statistically significant predictors in some groups. Higher thanatophobia scores also predicted lower scores for ratings of self-esteem in caring for elderly patients. Among senior medical students, those with lower thanatophobia scores tended to enter primary care residencies. Health professional educators may find this scale helpful both in pinpointing sources of caregivers' angst and useful in counseling students in management of terminally ill persons.

Adult↗
PubMed1997

Opioid detoxification using naloxone.

A method of brief inpatient opioid detoxification using naloxone is described. Daily injections of naloxone were administered to 20 patients who were dependent on opioids until no physical withdrawal reaction occurred. A reducing regime of clonidine and diazepam was used to treat withdrawal symptoms. Seventy-five percent of patients successfully completed detoxification within 6 days. Withdrawal symptoms were minimal and rapidly declined during treatment. Unlike other techniques using opioid antagonists detoxification with daily naloxone injections requires minimal medical supervision, enables full participation in a daily relapse prevention programme and results in discharge from hospital without medication for symptomatic relief.

Journal Article↗
PubMed1996

Rapid determination of amphetamine stereoisomer ratios in urine by gas chromatography-mass spectroscopy.

We describe a method for the determination of amphetamine optical isomer ratios. A simple basic extraction of amphetamine from urine is followed by on-column derivatization with (S)-(-)-N-(trifluoroacetyl)-L-prolyl chloride and analysis by gas chromatography-mass spectroscopy. This approach has been shown to be satisfactory for the separation of d- and l-amphetamine isomers and precision data shows the method to be reproducible. Patient data is presented to demonstrate the ability to differentiate between patients taking d-amphetamine and those using illicit (racemic) amphetamine by their l/d amphetamine ratio.

Amphetamine↗
PubMed1995

Helping community health centers adapt to changing environments: one foundation's response.

The history of community health centers (CHCs) reflects attitudes toward health care delivery in general. Developed as part of the war on poverty, they later survived the more conservative attitudes of the early 1970s to flourish in the late 1970s. In the 1980s, we again witnessed a reduction in the funding available to CHCs. In response to this, The Robert Wood Johnson Foundation (RWJF) established The Program to Strengthen Primary Care Health Centers. The program was designed to help centers to adapt to this environment by becoming more businesslike in their operations and decreasing their dependence on public dollars.

Community Health Centers↗
PubMed1995

Coagulation monitoring during extracorporeal membrane oxygenation: the role of thrombelastography.

Patients undergoing extracorporeal membrane oxygenation (ECMO) are at an increased risk for developing coagulopathies due to the adverse effects of extracorporeal circulation on the hemostatic mechanism. Methods of determining causative factors of bleeding diathesis are often inconsistent and non-specific. ECMO patients require aggressive transfusion therapy with autogenic blood products to stabilize and maintain hemostasis. The present study evaluated the coagulation status of newborn patients undergoing ECMO therapy, using a viscoelastic monitor (Thrombelastograph -TEG) that measures functional aspects of clot development and stabilization. Seventeen neonatal patients undergoing ECMO for severe respiratory dysfunction were entered into this study. Serial blood samples were obtained and routine coagulation assessment including fibrinogen concentration, platelet count and ionized calcium was performed. In addition, fibrin(ogen) degradation products (FDP), d-Dimers, antithrombin III and plasma free hemoglobin were measured. Transfusion indicators were established and total transfusion requirements recorded. TEG profiles were determined with the use of heparinase, an enzyme that degrades heparin but has little effect on other coagulation factors. The most commonly encountered complication was hemorrhaging which was diagnosed by laboratory and clinical assessment in 11 of 17 patients. Transfusion requirements (measured in ml/kg/ECMO hour) were the following: packed red blood cells--1.34 +/- 0.5; platelets--0.71 +/- 0.57; fresh frozen plasma--0.09 +/- 0.12; cryoprecipitate 0.05 +/- 0.05. Thrombelastograph profiles reflected hemostatic conditions that ranged from severe coagulopathies (DIC) to hypercoagulability. Interpretation of TEG profiles identified hemostatic abnormalities in 57 of 101 profiles (46.5%), with the most common etiology related to platelet dysfunction.(ABSTRACT TRUNCATED AT 250 WORDS)

Blood Coagulation Disorders↗
PubMed1994

Henoch-Schönlein purpura remitting in pregnancy and during sex steroid therapy.

This paper reports on a 22-yr old female patient with recurrent bouts of Henoch-Schönlein purpura since puberty occurring monthly at the time of menstruation. Remissions occurred during pregnancy, and on several occasions and in a dose responsive manner when the patient was prescribed birth control pills containing progesterone and oestradiol. Flares recurred when this therapy was discontinued. We hypothesize that this patient has an inflammatory disease involving neutrophil activation by excessive IgA, which is modulated by exogenous and endogenous sex steroids. It is unlikely that these hormonal influences are a common occurrence, but rather represent, in this case, a singular example of potential endocrine modulation of inflammatory disease.

Adult↗
PubMed1993

Neonatal complications after the administration of indomethacin for preterm labor.

BACKGROUND: The use of indomethacin as a tocolytic agent in pregnant women appears to be accompanied by a low incidence of neonatal complications. However, the neonatal effects of indomethacin have been studied primarily in infants born after 32 weeks' gestation. This study was designed to examine the incidence of neonatal complications in very premature infants. METHODS: We identified 57 infants delivered at or before 30 weeks' gestation whose mothers had been treated with indomethacin for preterm labor and matched them with 57 infants whose mothers had not received indomethacin. The infants in the two groups were matched for sex, gestational age at delivery (mean [+/- SD], 27.6 +/- 2.0 weeks), exposure to betamethasone for 24 hours or more before delivery, and rupture of membranes 24 hours or more before delivery. RESULTS: There were no significant differences between the two groups in birth weight, Apgar scores, cord-blood gas values, frequency of multiple gestation, or incidence of respiratory distress syndrome. The proportion of infants who required exogenous surfactant was similar, as were ventilator settings at 24 hours, the incidence of chronic lung disease, and the incidence of sepsis. The infants exposed to indomethacin had a lower urine output and higher serum creatinine concentrations during the first three days after delivery. More indomethacin-exposed infants had necrotizing enterocolitis (29 percent vs. 8 percent, P = 0.005), intracranial hemorrhage grade II to IV (28 percent vs. 9 percent, P = 0.02), and patent ductus arteriosus (62 percent, vs. 44 percent, P = 0.05). More indomethacin-exposed infants with a patent ductus arteriosus required surgical ligation because of either a lack of initial response or a reopening of the duct after postnatal indomethacin therapy (50 percent vs. 20 percent of the unexposed infants, P = 0.05). CONCLUSIONS: Antenatal indomethacin therapy for preterm labor appears to increase the risk of serious neonatal complications in infants born at or before 30 weeks' gestation.

Cerebral Hemorrhage↗
PubMed1993

Novel brainstem syndrome associated with prostate carcinoma.

Two patients successfully treated for prostatic cancer developed a progressive neurologic syndrome beginning with loss of voluntary horizontal eye movements followed by severe, persistent muscle spasms of the face, jaw, and pharynx. Both had mild gait unsteadiness, and one exhibited facial and abdominal myoclonus. Extensive diagnostic studies, including MRIs of the brainstem (with and without contrast), were normal. CSF examination showed mild pleocytosis and elevated IgG. Quantitative eye movement recordings documented selective involvement of voluntary horizontal saccades with sparing of horizontal slow eye movements. Neither patient had antineuronal antibodies in the blood. Postmortem examination revealed perivascular chronic inflammatory cells and microglial infiltration of the pons and medulla. One patient also had perivascular infiltrates in both mesial temporal lobes. Neuronal loss was localized to the pontine tegmentum, the medullary sensory nuclei, and the cerebellum. Brainstem motor nuclei were preserved. The clinical and pathologic findings suggest an autoimmune process (probably paraneoplastic) with selective damage to a subpopulation of brainstem neurons critical for horizontal eye movements and recurrent inhibition of bulbar nuclei.

Adenocarcinoma↗
PubMed1993

Hematological assessment of patients undergoing plasmapheresis during cardiac surgery.

Methods of reducing patient exposure to homologous blood transfusions include the technique of intraoperative plasmapheresis for the production of platelet rich plasma (PRP). The present study was designed to determine the patient benefits of PRP by examining hemostatic changes in coagulation screens and viscoelastic whole blood monitoring (Thrombelastography, [TEG]). One hundred fifteen patients undergoing elective cardiac surgery were prospectively randomized into a blinded study. Sixty-three patients had 20 percent of the circulating plasma volume sequestered prior to heparinization and pheresed into PRP, which was reinfused 10 minutes following heparin reversal with protamine. The control (CTR) group of 52 patients were exposed to no sequestration procedure. Patients were followed to discharge and 112 parameters, including anthropometric, operative, and postoperative factors, were measured. There were no significant differences between patient groups in preoperative, cardiopulmonary bypass (CPB), or surgical parameters. Average PRP volume was 600+/-100 ml with a total platelet yield of 1.1 billion platelets per patient. TEG indices were determined at four distinct times during the surgical procedure. The CTR group had significantly higher pre-CPB TEG indices of 2.3+/-1.2 and 2.1+/-1.2 (mean+/-SD), vs. 1.8+/-1.5 and 1.4+/-1.7 in the PRP group (p less than .04). Following heparin reversal, pre-PRP reinfusion TEG values were similar between groups, although both groups had significantly decreased indices when compared to pre-CPB values. Thirty minutes post-PRP infusion the treatment group had significantly improved TEG recovery when compared to the CTR group, 1.0+/-1.2 vs. 0.3+/-1.7 (p less than .05).(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗