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L Patterson

Publications and source records attributed to L Patterson.

At least 19 recordsLinked to original sources
PubMed1996

The relationship between mitochondrial state, ATP hydrolysis, [Mg2+]i and [Ca2+]i studied in isolated rat cardiomyocytes.

1. As ATP has a higher affinity for Mg2+ than ADP, the cytosolic magnesium concentration rises upon ATP hydrolysis. We have therefore used the Mg(2+)-sensitive fluorescent indicator Magnesium Green (MgG) to provide an index of changing ATP concentration in single rat cardiomyocytes in response to altered mitochondrial state. 2. In response to FCCP, [Mg2+]i rose towards a plateau coincident with the progression to rigor, which signals ATP depletion. Contamination of the MgG signal by changes in intracellular free Ca2+ concentration (the KD of MgG for Ca2+ is 4.7 microM) was excluded by simultaneous measurement of [Ca2+]i and [Mg2+]i in cells dual loaded with fura-2 and MgG. The response to FCCP was independent of external Mg2+, confirming an intracellular source for the rise in [Mg2+]i. 3. Simultaneous measurements of mitochondrial NAD(P)H autofluorescence and mitochondrial potential (delta psi m; .-1 fluorescence) and of autofluorescence and MgG allowed closer study of the relationship between [Mg2+]i and mitochondrial state. Oligomycin abolished the FCCP-induced rise in [Mg2+]i without altering the change in autofluorescence. Thus, the rise in [Mg2+]i in response to FCCP is consistent with the release of intracellular Mg2+ following ATP hydrolysis by the mitochondrial F1F0-ATPase. 4. The rise in [Mg2+]i was correlated with cell-attached recordings of ATP-sensitive K+ channel (KATP) activity. In response to FCCP, an increase in KATP channel activity was seen only as [Mg2+]i reached a plateau. In response to blockade of mitochondrial respiration and glycolysis with cyanide (CN-) and 2-deoxyglucose (DOG), [Mg2+]i rose more slowly but again KATP channel opening increased only when [Mg2+]i reached a plateau and the cells shortened. 5. Oligomycin decreased the rate of rise of [Mg2+]i delayed the onset of rigor and increased the rate of mitochondrial depolarization in response to CN-_DOG. Thus, with blockade of mitochondrial respiration delta psi m is maintained by the mitochondrial F1F0-ATPase at the expense of ATP reserves. 6. In response to CN-_DOG, the initial rise in [Mg2+]i was accompanied by a small rise in [Ca2+]i. After [Mg2+]i reached a plateau and rigor developed, [Ca2+]i rose progressively. On reperfusion, in hypercontracted cells, [Ca2+]i recovered before [Mg2+]i and [ca2+]i oscillations were sustained while [Mg2+]i decreased. Thus on reperfusion, full recovery of [ATP]i is slow, but the activation of contractile elements and the restoration of [Ca2+]i does not require the re-establishment of millimolar concentrations of ATP.

Adenosine Triphosphate↗
PubMed1996

Electrostimulation: addiction treatment for the coming millennium.

At a period of fundamental review of the health care system, it is timely to re-assess one of medicine's most intractable problems--the treatment of addictions. The apparently insoluble dilemmas posed by the acute and chronic withdrawal syndromes underlie universally high drop-out and relapse rates. In a decade of HIV and AIDS infection, poly-substance addiction, potent street drugs, and ossified treatment strategies, it is urgent that policy formulators investigate seriously a flexible system of non-pharmacological transcranial electrostimulation treatment, based on its record of rapid, safe, and cost-effective detoxification in several countries, as one innovative contribution to the challenges presented by addiction in the 1990s. This is a brief report of the introduction of NeuroElectric Therapy (NET) into Germany, describing the responses of the first 22 cases. The daily progress of a heroin addict and a methadone addict are detailed: both were treated as outpatients for 8 hours daily, for 7 and 10 days respectively.

Electric Stimulation Therapy↗
PubMed1996

Internal carotid artery gunshot wounds.

OBJECTIVE: To review a series of patients who sustained internal carotid artery (ICA) gunshot wounds. DESIGN, MATERIALS, AND METHODS: We retrospectively studied the demographics and clinical presentation, angiographic findings, methods of treatment, and outcome of 38 consecutive patients who had ICA injury identified by angiography. RESULTS: Thirty-four of 38 patients were symptomatic with neck hematomas (32 patients), active hemorrhage (12 patients), and/or neurologic deficit (10 patients). Angiography showed active bleeding in 22 patients and occlusion in 16 patients. Twelve patients were treated operatively by ligation (seven patients), repair (four patients), or intracranial/extracranial bypass (one patient). Twenty-six patients were managed nonoperatively either by angioplasty (one patient), embolotherapy (17 patients), or observation alone (eight patients). Percutaneous balloon catheters were also used in three patients for vascular control of the ICA before operative repair or as a method of assessing intracranial collateral circulation. The mortality of 18.4% was largely related to strokes. CONCLUSIONS: Penetration of the ICA is a very severe injury with a high mortality. The major cause of death in this series was related to neurologic damage associated with carotid injury and shock. However, neurologic deficit among the survivors was uncommon and often resulted from emboli. Interventional radiology can play an important role in the management of these wounds and often obviates the need for operative exploration.

Adolescent↗
PubMed1996

Combining multiple data bases for outcomes assessment.

Often, information from a single database cannot answer important clinical outcomes or research questions. This article describes efforts to link multiple databases to extract useful health care information. One project, conducted by the Keystone Peer Review Organization (KePRO), focused on the number of combined right and left heart catheterizations done in patients, who were admitted to the hospital for a diagnostic left heart catheterization, for primary coronary artery disease. The study linked data from hospital billing records, patient records, and insurance companies' records. Another effort involves two studies of Acute Myocardial Infarction (AMI) by KePRO and Pennsylvania Health Care Cost Containment Council. The final case study describes the Crash Outcomes Data Evaluations Systems (CODES) project, conducted by the Pennsylvania Department of Health. To determine if seat belts help to prevent injuries, cut costs, and save lives, it was necessary to build a complete record across multiple sights of care from the crash until final outcome. These examples illustrate the challenges and the advantages of using multiple databases to assess health care outcomes.

Accidents, Traffic↗
PubMed1995

Cerebellar Purkinje cells from the lurcher mutant and wild-type mouse grown in vitro: a light and electron microscope study.

Lurcher is an autosomal semidominant murine mutation. Lurcher heterozygotes (+/Lc) lose all their cerebellar Purkinje cells by adulthood. Explants from 2 days postnatal (P2) wild-type (+/+) and +/Lc cerebellar cortex were grown in vitro to investigate the role of local neuronal environment and afferent input on the degenerating +/Lc Purkinje cell. In Lurcher explants, Purkinje cells were maintained for up to 25 days in vitro. No significant difference was observed between +/+ and +/Lc Purkinje cell numbers from 10 to 20 days in vitro, as revealed by calbindin-D immunoreactivity. Growing +/Lc explants in association with +/+ explants resulted in no significant difference in Purkinje cell survival (10-20 days in vitro). Image analysis of the gross morphology of calbindin-D-immunostained Purkinje cells from +/+ and +/Lc explants grown in vitro revealed a significant decrease in the total area and dendritic lengths of +/Lc Purkinje cells (15 and 20 days in vitro). The fine structure of +/Lc and +/+ Purkinje cells was examined under the electron microscope (10-25 days in vitro). No difference in ultrastructure was observed between +/Lc and +/+ Purkinje cells grown in vitro, and many features similar to normal Purkinje cell development in vivo were present. These included monosynaptic parallel fibre synapses with Purkinje cell dendritic spines, other interneuron synapses with Purkinje cell dendrites and soma, astroglial investment, and minimal extracellular space in the neuropil. Unusual features observed included a persistence of the perisomatic spines in some Purkinje cells, an absence of Nissl bodies in the Purkinje cell perikaryon, naked Purkinje cell dendritic spines, and occasional heterologous synapses. The results are discussed in the light of previous chimeric analysis of the Lurcher mutation, and a hypothesis is put forward to explain the survival of +/Lc Purkinje cells in vitro.

Animals↗
PubMed1994

Waiting time after non-depolarizing relaxants alter muscle fasciculation response to succinylcholine.

The purpose of the study was to determine the effect of nondepolarizing muscle relaxants and waiting time on muscle fasciculations after succinylcholine in anaesthetized patients. Adult men and women, 60-80 kg, received pretreatment doses of atracurium 5 mg (n = 160), pancuronium 1 mg (n = 123), d-tubocurarine 3 mg (n = 97), or vecuronium 1 mg (n = 62). Waiting times between pretreatment and succinylcholine, 100 mg, ranged between 0.6 and 5 min. Data points (presence or absence of fasciculations and waiting time) were entered for each patient. Waiting time response curves were obtained between the logit transformation of the probability of no fasciculations and the log waiting time for each drug. Statistical differences between wait time response curves were determined by non-overlapping of the associated 95% confidence intervals. The frequency of muscle fasciculations was reduced with increased waiting time for all nondepolarizers tested. Following wait times of three, four and five minutes, the probability of not fasciculating was greatest with d-tubocurarine (90, 97 and 99%, respectively) and atracurium (89, 93 and 96%). Corresponding values for pancuronium were 70, 82 and 88% and for vecuronium were 74, 82 and 86%. Waiting times to prevent fasciculations in 80% and 90% of patients were shorter with d-tubocurarine (2.46 and 3.02 min, respectively) or atracurium (2.16 and 3.24 min) than pancuronium (3.77 and 5.35 min) or vecuronium (3.73 and 6.36 min).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1993

Magnetic resonance spectroscopy in social phobia: preliminary findings.

Proton localized magnetic resonance spectroscopy was studied in 20 social phobics and 20 age- and sex-matched controls. Stimulated Echo Acquisition Mode volume element localization was used with chemical shift imaging. Choline and creatine signal-to-noise ratios (SNRs) were significantly lower in social phobia than in controls in subcortical, thalamic, and caudate areas. In the social phobic group, N-acetylaspartate (NAA) SNR was significantly lower in cortical and subcortical regions, and ratios of NAA to other metabolites were lower in social phobia. Choline, creatine, and NAA SNRs were inversely correlated to total social phobia and fear symptoms, as measured by the Brief Social Phobia Scale, in the thalamic and noncortical gray areas. In a small number of patients who received clonazepam, posttreatment SNRs generally increased relative to baseline. Our results suggest a promising place for magnetic resonance spectroscopy in social phobia and also indicate potential pharmacodynamic uses of this technique.

Adult↗
PubMed1992

A randomized double-blind study of neuroelectric therapy in opiate and cocaine detoxification.

Prior research on the use of transcranial neuroelectric stimulation suggested that the application of low-amperage, low-frequency alternating current via surface electrodes placed in the mastoid region could relieve the physiological signs and subjective symptoms of withdrawal and craving during opiate detoxification. These effects were reported without gradual tapering of the opiate or the addition of other medications. To test the efficacy of one particular form of neuroelectric therapy (NET), a double-blind, randomized, placebo-controlled study was conducted comparing active NET and placebo NET in the treatment of withdrawal and stabilization of 18 opiate-dependent and 25 cocaine-dependent subjects. Scores on scales for measuring substance withdrawal and craving for each abused substance, as well as the multiple dimensions of mood, were compared for degree of difference across the 10 days of treatment. There was an overall completion rate of 88%, with both cocaine and opiate groups reporting a comfortable detoxification and substantial improvement over the course of a 12-day hospitalization. There was no significant difference between the active or placebo groups, suggesting that placebo was as effective as active NET in reducing drug withdrawal or craving during cocaine and opiate detoxification. However, all placebo patients received 0.2 mA of current, which may have provided a degree of active current. Suggestions are offered for future research.

Adult↗
PubMed1992

Effects of dietary fat on cholesterol movement between tissues in CBA/J and C57BR/cdJ mice.

Differences in dietary fats cause differences in cholesterol metabolism in mice. CBA/J mice are resistant to diet-induced hypercholesterolemia and atherosclerosis; they adjust hepatic hydroxymethyl-glutaryl-CoA reductase activity (HMGR) to maintain homeostasis; C57BR/cdJ mice are susceptible, but young animals are thought to maintain homeostasis by changing fecal excretion of sterols. Compartmental modelling of movement of [4-14C]cholesterol was used to analyze movement of cholesterol between serum and liver, heart, and carcass in mice fed 40 en% fat, polyunsaturated to saturated fatty acid ratio (P/S) = 0.24 (US74) or 30 en% fat, P/S = 1 (MOD). Dietary effects were quite pronounced, while strain effects were more subdued. The C57/cdJ animals appear to regulate the overall cholesterol balance by reducing synthesis, as do the CBA/J animals, even though synthesis is not reduced to the same degree as in the CBA/J animals. Both diet and strain influence the whole-animal turnover rate, with slower turnover occurring for C57BR/cdJ animals and animals fed the US74 diet.

Animals↗
PubMed1991

The influence of maternal undernutrition in ovine twin pregnancy on fetal growth and Doppler flow-velocity waveforms.

The effects on placental blood flow velocity of maternal undernutrition during mid pregnancy were investigated in 38 twin bearing pregnant sheep by Doppler analysis of umbilical and uteroplacental arterial waveforms. Mid pregnancy undernutrition resulted in fetal growth restriction manifest at term gestation by reduced mean birth weight. Arterial waveform systolic/diastolic ratios from the umbilical and uteroplacental arterial circulations were not influenced by maternal nutrition either during the dietary deprivation or during a subsequent period of dietary supplementation. An effect of heart rate on systolic/diastolic ratios could not be demonstrated. The results indicate that the fetus responds to mid pregnancy maternal undernutrition with restricted growth but without alterations in systolic/diastolic ratios in umbilical or uteroplacental arterial waveforms.

Animals↗
PubMed1990

Effects of maternal cigarette smoking on ultrasonic measurements of fetal growth and on Doppler flow velocity waveforms.

Serial ultrasound biometry and Doppler flow velocity waveform analysis were used to measure the effects of maternal smoking in a prospective study of 535 pregnancies. Smoking was associated with significant reductions in maternal weight gain, birthweights and placental weights. Decreased fetal biparietal diameter measurements were observed in pregnancies of smoking women; this effect was maximal at 24 weeks' gestation, was restricted to male fetuses and was not associated with altered head circumferences after birth. Umbilical artery and uteroplacental systolic/diastolic ratios were similar in pregnancies of smoking and non-smoking women, indicating that the effects of smoking on placental vascular resistance are periodic rather than continuous. The findings of this study confirm the need for studies of fetal growth to include prenatal measurements obtained by high resolution ultrasound imaging, rather than relying on findings obtainable by examination of the infant after birth.

Adult↗
PubMed1990

The effect of heart rate on Doppler flow velocity systolic-diastolic ratios in umbilical and uteroplacental arterial waveforms.

In an analysis of the influence of heart rate on Doppler flow velocity waveform-systolic/diastolic ratios from 1555 umbilical artery waveform studies and from 1497 uteroplacental waveform studies, a negative correlation was observed between the ratio and the corresponding heart rate. This relationship was not influenced by gestational age and was similar in pregnancies with normal outcomes when compared with all pregnancies. The magnitude of this inverse relationship is such that the effect of heart rate on systolic/diastolic ratios must be considered when Doppler flow velocity waveform analyses are used as experimental tools to assess placental vascular resistance but it does not appear to be an important factor in general clinical practice when measurements are made during fetal inactivity and when heart rates are within normal ranges.

Blood Pressure↗
PubMed1990

Transrectal ultrasonography in the evaluation of the infertile man: a report of 3 cases.

The traditional evaluation of the infertile man with azoospermia or low ejaculate volume includes determination of serum testosterone and follicle-stimulating hormone levels, a seminal fructose test, post-ejaculate urinalysis and, sometimes, vasography. Transrectal ultrasonography, a technique currently familiar to most urologists, recently has been added to our diagnostic armamentarium. This office-based imaging procedure provides an accurate assessment of the prostate, ejaculatory ducts and seminal vesicles, which can be helpful in the evaluation of certain infertile patients. We describe 3 patients who presented with either azoospermia or decreased ejaculate volume in whom transrectal ultrasonography had a critical role in the fertility evaluation. The clinical indications for and interpretation of transrectal ultrasonography in the infertile population are described. Transrectal ultrasonography currently is the most accurate, inexpensive and readily available noninvasive imaging technique used to diagnose obstruction of the ejaculatory ducts in the infertile patient with either azoospermia or low ejaculate volume.

Adult↗
PubMed1987

The sensitivity of radionuclide and thermodilution techniques to detect cardiac dysfunction in the baboon model during prolonged anaesthesia.

This study was undertaken to evaluate the fluctuations of cardiac parameters in a baboon model during pentobarbitone anaesthesia which will serve as a baseline control for shock studies. Thermodilution and radionuclide methods were used to determine cardiac parameters. Radionuclide studies were repeated without any cardiac catheters to assess the effect of these on cardiac performance. The results represent baseline fluctuations in cardiac parameters against which cardiac dysfunction can be diagnosed in shock studies. The results also indicate that cardiac catheterisation does not affect cardiac performance significantly.

Anesthesia, Intravenous↗
PubMed1984

Management of pain in sickle cell disease using biofeedback therapy: a preliminary study.

Fifteen patients with a history of painful episodes of sickle cell disease were given training in progressive relaxation, thermal biofeedback, cognitive strategies, and self-hypnosis to help them develop self-management skills to relieve pain. Results show a 38.5% reduction in the number of emergency room visits, a 31% reduction in the number of hospitalizations, and a 50% reduction in the inpatient stay during the 6 months since the beginning of therapy compared to 6 months prior to therapy. Analgesic intake was reduced by 29% for those who were using it regularly. This is a preliminary study, and the results are considered only as suggestive of the potential use of biofeedback therapy and behavioral management in alleviating painful episodes in sickle cell disease.

Adult↗
PubMed1982

Arcus senilis: an important forensic physical finding.

Arcus senilis is a deposition of lipid at the corneal periphery. It is dependent on vascularity for formation and is not a degenerative change. The prevalence of arcus increases with age, and it appears more in blacks and males. It appears to be related to cardiovascular disease but has not been shown to be a reliable predictor of the disease. We studied the incidence of arcus width with age and found no definite correlation.

Adolescent↗
PubMed1980

The effectiveness of group psychotherapy during the first three weeks of hospitalization. A controlled study.

Insight-oriented group psychotherapy is a common modality of treatment on inpatient psychiatric wards, yet is effectiveness for acutely hospitalized patients has not been adequately studied. A comparison was made of the effects of three experimental conditions (insight-oriented group psychotherapy, activity-oriented task group, and unstructured control condition) on 86 acutely hospitalized psychiatric patients at a United States Air Force teaching hospital. The group psychotherapy and task group patients did not show greater improvement after 20 days of hospitalization than control patients. In fact, significantly more psychotic patients scored worse in the group psychotherapy condition. It is suggested that insight-oriented group psychotherapy may not be an effective treatment modality during the first 3 weeks of psychiatric hospitalization, especially for psychotic patients.

Adolescent↗