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J Jennings

Publications and source records attributed to J Jennings.

At least 19 recordsLinked to original sources
PubMed2005

MRI and 2D-CSI MR spectroscopy of the brain in the evaluation of patients with acute onset of neuropsychiatric systemic lupus erythematosus.

MRI and 2D-CSI spectroscopy were performed in eight patients with systemic lupus erythematosus who presented with acute onset of neuropsychiatric lupus (NP-SLE), and in seven normal controls to evaluate for differences in metabolic peaks and metabolic ratios between the two groups. Also, the interval change of the metabolic peaks and their ratios during treatment in the NP-SLE patient group was evaluated. Metabolic peaks for N-acetyl-aspartate (NAA), choline (Cho), creatine (Cr), and lactate/lipids (LL) and their ratios (NAA/Cr, NAA/Cho, Cho/Cr, LL/Cr) were determined at initial presentation and 3 and 6 months later. In the eight lupus patients compared to the seven normal controls, NAA/Cho ratios were lower at presentation (1.05 vs 1.25; p = 0.004) and decreased even further at the three month follow-up (0.92 vs 1.05; p = 0.008). In contrast, both Cho/Cr (1.42 vs 1.26; p = 0.026) and LL/Cr ratios (0.26 vs 0.19; p = 0.002) were higher in the lupus patients at presentation compared to the controls and did not significantly change at three and six months follow-up. The NAA/Cr ratios were lower in the lupus patients compared to the controls at presentation but the difference was not statistically significant. However, the mean NAA/Cr significantly decreased from the initial examination to the three month follow-up (1.42 vs 1.32; p = 0.049) but did not significantly change from the three to the six month follow-up examinations. The NAA/Cr, Cho/Cr, and NAA/Cho ratios varied significantly (p < 0.05, p < 0.05, p < 0.05, respectively) between the 17 different locations measured in the brain in all eight patients and seven controls. Both the NAA/Cr ratios and the Cho/Cr ratios were also significantly lower in the gray matter than in the white matter (p < 0.0001) in both patients and controls, whereas the LL/Cr and NAA/Cho ratios were not significantly different. In conclusion, 2D-CSI MR spectroscopy may be useful in the early detection of metabolic CNS changes in NP-SLE patients with acute onset of new neurological symptoms as well as in the follow-up after treatment to assess presence and changes in metabolic brain injury. However, although there are detectable differences between normal individuals and lupus patients it is currently unclear whether these relate to the acute episode. Future studies are needed comparing NP-SLE patients with active CNS involvement with those inactive disease.

Acute Disease↗
PubMed2001

Search for the decay KL --> pi(0)e+e-.

We report on a search for the decay KL-->pi(0)e+e- carried out by the KTeV/E799 experiment at Fermilab. This decay is expected to have a significant CP violating contribution and the measurement of its branching ratio could support the Cabibbo-Kobayashi-Maskawa mechanism for CP violation or could point to new physics. Two events were observed in the 1997 data with an expected background of 1.06+/-0.41 events, and we set an upper limit B(KL-->pi(0)e+e-)<5.1 x 10(-10) at the 90% confidence level.

Journal Article↗
PubMed2000

Implementing and maintaining school-based mental health services in a large, urban school district.

The Dallas (Texas) Public Schools established the first school-based health center in the United States in 1969. In 1993 a partnership between two school principals, a school mental health professional, and the medical director of the county mental health center was the impetus for the first comprehensive school-based mental health center in Texas. In 1995 the programs joined together as Youth and Family Centers (YFCs) to provide physical health, mental health, and other support services to students and their families. The 10 strategically located school-based centers are directed by licensed mental health professionals employed by the district who lead a multidisciplinary team of physical health and mental health providers. Students served by the YFCs have fewer discipline problems, course failures, and school absences.

Adolescent↗
PubMed2000

Evaluation of New York State's Child Health Plus: methods.

BACKGROUND: The State Children's Health Insurance Program (SCHIP) is the largest public investment in child health care in 30 years, targeting 11 million uninsured children, yet little is known about the impact of health insurance on uninsured children. In 1991 New York State implemented Child Health Plus (CHPlus), a health insurance program that was a prototype for SCHIP. A study was designed to measure the association between CHPlus and access to care, utilization of services, and quality of care. METHODS: The setting was a 6-county region in upstate New York (population 1 million) around and including the city of Rochester. A before-and-during design was used to compare children's health care for the year before they enrolled in CHPlus versus the first year during CHPlus, for 1828 children (ages 0-6.99 years at enrollment) who enrolled between November 1, 1991 and August 1, 1993. An additional study involved 187 children 2 to 12.99 years old who had asthma. Parents were interviewed to assess demographic characteristics, sources of health care, experience with CHPlus, and impact of CHPlus on their children's quality of care and health status. Medical charts were reviewed to measure utilization and quality of care, for 1730 children 0 to 6.99 years and 169 children who had asthma. Charts were reviewed at all primary care offices and at the 12 emergency departments and 6 public health department clinics in the region. CHPlus claims files were analyzed to determine costs during CHPlus and to impute costs before CHPlus from utilization data. ANALYSES: Logistic regression and Poisson regression were used to compare the means of dependent measures with and without CHPlus coverage, while controlling for age, prior insurance type, and gap in insurance coverage before CHPlus. CONCLUSIONS: This study developed and implemented methods to evaluate the association between enrollment in a health insurance program and children's health care. These methods may also be useful for evaluations of SCHIP.

Asthma↗
PubMed1999

Intracytoplasmic sperm injection overcomes previous fertilization failure with conventional in vitro fertilization.

OBJECTIVE: To evaluate the outcome of intracytoplasmic sperm injection (ICSI) in patients with previous idiopathic fertilization failure (< or =20% fertilization rate) after conventional IVF. DESIGN: Retrospective analysis. SETTING: IVF program at a university medical center. PATIENT(S): Twenty-five patients who underwent 38 ICSI cycles after experiencing unexplained fertilization failure with conventional IVF (group A) and 87 patients who underwent 118 ICSI cycles for male factor indications during the same period (group B). INTERVENTION(S): Intracytoplasmic sperm injection was performed in a subsequent cycle after fertilization failure with conventional IVF. MAIN OUTCOME MEASURE(S): Outcomes of IVF were compared between groups A and B. RESULT(S): Fertilization was achieved with ICSI in all patients with previous fertilization failure. The mean (+/- SD) fertilization rate (68%+/-21% vs. 64%+/-22%), implantation rate per embryo (22.6% vs. 20%), and delivery rate per cycle (47.3% vs. 49.1%) did not differ significantly between groups A and B. Overall, 72% of patients with previous unexplained fertilization failure had a successful pregnancy after ICSI. CONCLUSION(S): Intracytoplasmic sperm injection can overcome unexplained fertilization failure caused by a potentially occult gamete abnormality, with the same fertilization, implantation, and pregnancy rates as are seen in patients with abnormal sperm parameters.

Adult↗
PubMed1999

Mutuality and preparedness of family caregivers for elderly women after bypass surgery.

The purposes of this study were to identify caregivers' feelings of mutuality and reported preparedness for caregiving at hospital discharge and to examine the relationship between these measures and the recovery outcomes of elderly women after coronary artery bypass graft (CABG) surgery. A sample of 49 dyads was followed at discharge, 6 weeks, 3 months, and 6 months. The caregivers' Mutuality Scale (MS) scores and Preparedness for Caregiving (PCS) scores at discharge indicated positive feelings about the relationship with the elderly woman and their preparedness, and both measures were positively correlated with the self-report recovery measures at 3 months (p < .05). Nevertheless, at 3 months the MS scores were significantly lower than at discharge (p < .05), indicating stress in the caregiver-patient relationship. The MS and PCS may be useful tools for assessing situations and directing nursing interventions during discharge planning.

Adaptation, Psychological↗
PubMed1999

Utility of produce ratios to track fruit and vegetable consumption in a rural community, church-based 5 A Day intervention project.

Previous research suggests that grocery store characteristics may be useful in evaluating community-based dietary interventions. We undertook a study to determine whether produce ratios (ratios of produce sales to total grocery sales) were a useful indicator of fruit and vegetable (F & V) consumption in a church-based, community intervention trial that promoted 5 A Day guidelines within 10 rural counties of North Carolina. Produce ratios were collected from stores identified by participants in the Black Churches United for Better Health Project. Baseline and study period data for 21 stores in intervention counties and 18 stores in nonintervention counties were compared using repeated-measures analysis of variance. Produce ratios were significantly associated with seasonality (p < 0.0001), but no differences were seen between the two groups of stores. These findings do not support data from individual telephone surveys, which showed significant differences in F & V consumption between participants in the two groups. Our inability to detect differences at the store level may have been due to 1) the incapacity of produce ratios to capture F & V purchases that were juice, frozen, or canned products; 2) shifts in procuring F & Vs from grocery stores to other sources (i.e., gleaning and produce cooperatives); 3) the modest proportion of shoppers that received the full intervention dose; and 4) a general lack of power to detect differences at the store level. Therefore, although produce ratios did not serve as a valid measure for this project, if their limitations are recognized and compensated for, they may have applicability for future investigations that monitor F & V consumption.

Black or African American↗
PubMed1994

The astrocyte response to gamma-aminobutyric acid attenuates with age in the rat optic nerve.

There is increasing evidence that glial cells respond to the inhibitory neurotransmitter gamma-aminobutyric acid (GABA), and astrocytes have been shown to possess GABAA receptors both in vivo and in vitro. A recent study by Sakatani et al. (Proc. R. Soc. Lond. B247, 155 (1992)) demonstrated the transient expression of functional GABAA receptors in the developing rat optic nerve, but axonal and glial components of the response were not distinguished. To help address this problem, we have determined the electrophysiological response to GABA in astrocytes of the isolated intact optic nerves from neonatal rats, identified morphologically following intracellular injection of horseradish peroxidase. Astrocytes responded to GABA by a GABAA receptor-mediated depolarization which attenuated gradually during post-natal development; astrocytes in 21-day-old nerves were not observed to respond to GABA. The results indicate the transient presence of functional GABAA receptors in developing rat optic nerve astrocytes in situ, and we speculate upon a role for GABA in glial signalling and the organization of axonglial interrelations during development.

Aging↗
PubMed1994

Response of astrocytes to gamma-aminobutyric acid in the neonatal rat optic nerve.

The electrophysiological response to gamma-aminobutyric acid (GABA) was determined in astrocytes of the isolated intact optic nerves of rats aged 8 to 12 days old, identified morphologically following intracellular injection of horseradish peroxidase. At this age, astrocytes had a mean (+/- S.E.M.) resting membrane potential of -62.25 +/- 1.9 mV (n = 32), and responded to GABA by a depolarization characterized by an initial peak of mean 9.1 +/- 0.6 mV, which was not sustained and fell to a plateau level. The effect of GABA was mimicked by the GABAA-receptor agonist muscimol, but not by the GABAB-receptor agonist baclofen, and was reduced in the presence of the GABAA-receptor antagonist bicuculline. Astrocytes responded to 10 mM [K+]o by a single phase depolarization of 16 +/- 2 mV (n = 5). It is concluded that GABA acts directly on astrocytes and its effect is not mediated by K+ released by axons. This study indicates the presence of functional GABAA receptors in neonatal rat optic nerve astrocytes in situ. The results suggest immature astrocytes may be the source of the GABA response described in two recent studies on the rat whole optic nerve preparation. The astrocyte response to GABA may be important in axon-glial signalling during development.

Animals↗
PubMed1992

Human antibody response to the intravenous and intraperitoneal administration of the F(ab')2 fragment of the OC125 murine monoclonal antibody.

We have characterized the human immune response against murine monoclonal antibodies (HAMA) in 18 patients following administration of the F(ab')2 fragment of the murine monoclonal antibody OC125. OC125 is directed against the CA125 antigen, present on the surface of many human ovarian cancers. An affinity matrix was used to separate serum into immunoglobulin-containing and immunoglobulin-free fractions. HAMA titer was determined on the immunoglobulin fraction with an OC125 sandwich enzyme-linked immunosorbent assay (ELISA). All patients developed an HAMA response, despite the use of F(ab')2 fragments and small amounts (1-4 mg) of antibody. It may be that the intraperitoneal (i.p.) route provides a more marked HAMA response. Enzyme-linked sandwich immunoassays were also used to determine anti-isotype and anti-idiotype titers. Anti-isotype titers were analyzed with antigen irrelevant, isotype-matched murine antibodies and OC125-HRPO. Anti-idiotypes titers were assessed in a sandwich assay that utilized F(ab')2 and F(ab') fragments of OC125. The anti-isotype response tended to be of low titer and short duration, while the anti-idiotype response was of high titer and remarkably persistent. HAMA interfered in an unpredictable manner with the correct measurement of serum levels of CA125 in an enzyme immunoassay using OC125. Corrected values of CA125 could be obtained by measurement of antigen in the immunoglobulin-free fraction of serum. The response of one patient, who developed a markedly elevated anti-idiotype titer after serial i.v./i.p. injections, was further characterized and found to contain an antibody consistent with an anti-anti-idiotype to the CA125 antigen.

Adenocarcinoma↗
PubMed1991

A review of the role of established tumour markers.

Increasing numbers of commercial assays for the established tumour markers are available which are capable of excellent analytical performance. Whilst all these assays are useful as research tools, their clinical value is more limited and should be appreciated before any decision is taken to offer a tumour marker assay service. 1. Calcitonin (medullary carcinoma of thyroid), alphafetoprotein (hepatoma) and human chorionic gonadotrophin (choriocarcinoma) are the only tumour markers that can be used for screening for malignancy in high risk populations. 2. Hormones, paraproteins, alphafetoprotein, human chorionic gonadotrophin and prostate specific antigen are valuable in establishing the diagnosis of certain tumour types. 3. Alphafetoprotein and human chorionic gonadotrophin concentrations at the time of diagnosis are of value in predicting prognosis in specific tumour types. 4. Although their sensitivity for a particular tumour type may be poor, most tumour markers can be used for monitoring the therapy and follow-up of selected marker positive patients. Optimal clinical results of the management of patients with malignancy are usually obtained by specialist centres, and laboratory tumour marker services should be established so that they are appropriate to local oncology specialities.

Biomarkers, Tumor↗
PubMed1991

Umbilical artery resistance index as a screening test for fetal well-being. I: Prospective revealed evaluation.

Abnormalities of the human fetoplacental circulation, a common association with fetal morbidity and mortality, can be detected by Doppler ultrasound examination of the umbilical arterial blood flow. The value of this procedure as a screening test was assessed in 369 women whose fetuses were evaluated on 1354 occasions using both computerized antenatal fetal heart rate (FHR) analysis and continuous-wave Doppler ultrasound. The FHR analyses were used to guide management, but the results of the Doppler measurements were not made available to the clinical staff. The mean duration of each nonstress test (NST) was 27 minutes, compared with 6 minutes for the Doppler examination. Increased resistance indices in the umbilical artery identified those fetuses with an abnormal NST or a clinical diagnosis of antenatal distress with a high sensitivity and negative predictive value. The high rate of false-positive results with respect to these two end points was reduced when fetal distress in labor was included as a third end point. The value of the Doppler examination in predicting fetal distress was applicable to appropriately grown as well as small for gestational age fetuses.

Female↗
PubMed1991

Umbilical artery resistance index as a screening test for fetal well-being. II: Randomized feasibility study.

To determine whether the time taken for fetal assessment could safely be reduced by preliminary screening with Doppler ultrasound, 897 women having fetal assessment in the high-risk unit of the John Radcliffe Hospital, Oxford, were randomly allocated to two groups. In the Doppler group, preliminary assessment was by umbilical artery resistance estimation, and in the fetal heart rate (FHR) group by computerized FHR analysis. To minimize the risk of failing to recognize fetal distress, the criteria for using the nonallocated method as well were deliberately conservative. Thus, 66% of the 1869 Doppler studies done in the Doppler group and 39% of the 2069 FHR tests done in the FHR group needed to be followed by the nonallocated tests. Trained nursing staff performed the Doppler studies as part of their routine duties. Doppler studies were unsuccessful in obtaining a result on 26% of the occasions. Under the above clinical circumstances, preliminary Doppler screening did not reduce the time taken for fetal assessment. There were no significant differences in perinatal outcome between the groups, except that emergency as opposed to elective cesareans were less frequent in the Doppler group. As this finding was not predicted by previous hypothesis, it needs to be confirmed.

Adult↗
PubMed1990

Studies of the mechanism by which androgens enhance mitogenesis and differentiation in bone cells.

Recently, we reported a direct effect of androgens on murine and human bone cells to stimulate bone cell proliferation and differentiation. To test whether this effect of androgenic steroids might be mediated by growth factors, we measured relative concentrations of insulin-like growth factor-I and -II (IGF-I and IGF-II) and transforming growth factor-beta (TGF beta) in the conditioned medium from androgen-treated murine calvarial cell cultures. Only the concentration of TGF beta was increased. Consistent with the increased secretion of TGF beta in the mouse calvarial cell system, we observed an increased expression of TGF beta mRNA in a normal human osteoblastic cell system. We also determined whether androgens alter the response to growth factors. We found that dihydrotestosterone (DHT) treatment enhanced the mitogenic effects of fibroblast growth factor (FGF) and IGF-II but not those of IGF-I. The enhanced effect of FGF and IGF-II after DHT pretreatment was not affected by addition of TGF beta-blocking antibodies or by changing the culture medium. This indicated that in addition to increased release of TGF beta, another mechanism might be involved in the action of DHT on human and murine bone cells. Thus, we investigated the binding of human IGF-II to human osteoblastic cells and observed an increase in IGF-II binding after DHT treatment. Our results are consistent with a mechanism of action of androgens on bone cells that involves the induction of TGF beta and, in addition, may sensitize the cells to show an enhanced response to FGF and IGF-II, possibly by changing the receptor binding of mitogenic growth factors.

Androgens↗
PubMed1989

A placebo-controlled, double-blind crossover study of naltrexone hydrochloride in outpatients with normal weight bulimia.

The endogenous opioid system plays an important role in the control of feeding behavior. Previous research has shown that antagonism of endogenous opioids will suppress feeding in certain models in both human and infrahuman species. In the current study, 16 normal-weight bulimic women were treated with low-dose naltrexone, the long-acting, orally active narcotic antagonist, and placebo in a crossover design. The use of the active drug was not associated with a clinically significant reduction in binge eating or vomiting episodes. Suggestions for further research in this area are offered.

Adult↗
PubMed1988

Effect of bone matrix-derived growth factors on skull and tibia in the growing rat.

Aberration in cranial skeletal morphology during growth due to metabolic bone diseases associated with hypocalcemia is related to abnormalities in cranial suture growth. It was found in previous experimental studies that a changed cranial growth pattern induced by hypocalcemia and secondary hyperparathyroidism was dependent on a decreased bone apposition in viscerocranial growth sites. Of interest was the observation that obliterative osteogenesis occurred with this disturbance. In vitro studies have shown that when bone resorption is stimulated by parathyroid hormone, mitogenic factors for bone cells are released from the matrix. The aim of the current study was to elucidate a possible local regulatory mechanism for bone growth especially with regard to cranial growth. Two groups of young rats were injected daily with 150 micrograms and 750 micrograms respectively of bone matrix-derived growth factor preparation (BMDGF) for 2 weeks. By using cephalometric analysis, the BMDGF administration was shown to alter skull morphology during growth. Since the high doses of BMDGF caused markedly more changes than the low dose, the overall effect on craniofacial growth seemed to be dose dependent. The high dose of BMDGF induced a decrease in cortical bone apposition found in this region, as well as in the diaphysis of the tibia. Also a change in position of the viscerocranium in relation to the cranial base was found in the BMDGF-treated rats: the flexure between the viscerocranium and the cranial base being greater compared with the normal skull. This change in relationship seemed to be related to the enhanced bone apposition found in the viscerocranial sutures of BMDGF-treated rats.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗