Search PubMed⌕ Search

Biomedical subjects

L Schwartz

Publications and source records attributed to L Schwartz.

At least 55 records · Page 3Linked to original sources
PubMed1999

Short- and long-term outcome of balloon angioplasty for compromised side branches after intracoronary stent deployment.

During coronary stent deployment there is a risk of compromising side branches, which can result in chest pain. Compromised side branches can be reopened by balloon angioplasty through the side of the stent. In a consecutive series of 10 patients with side-branch compromise and chest pain, balloon angioplasty through the side of the stent resolved the ischemia in all cases. The stented segment showed no deterioration following side-branch angioplasty. Six-month follow-up angiography showed a restenosis in the branch vessel of eight patients. The stented parent vessel restenosed in four patients. Therefore, side-branch balloon angioplasty after coronary stenting for ongoing ischemia is technically feasible and immediately effective. Restenosis of the branch occurs in most cases.

Adult↗
PubMed1999

Pain in persons with cerebral palsy.

OBJECTIVE: To examine the nature and scope of pain in persons with cerebral palsy (CP). DESIGN: Standardized interviews to assess demographics, pain experiences, and the impact of pain on activities. SUBJECTS: Ninety-three adults with CP recruited from medical clinics at the University of Washington and local residential and community housing for persons with developmental disabilities. MAIN OUTCOME MEASURES: Weekly and 3-month pain intensities, chronic pain grade, interference in daily activities caused by pain, and pain-exacerbating and pain-relieving factors. RESULTS: Sixty-two subjects (67%) reported one or more areas of pain of > or =3 months' duration. Lower extremity pain and back pain were the most common complaints. Fifty-six percent of the subjects reporting pain indicated it occurred daily. Mean average pain intensity, graded on a scale of 0 (no pain) to 10 (pain as bad as could be), was 3.16 (SD = 2.45) in the preceding week and 4.45 (SD = 2.34) in the previous 3 months. Approximately 53% of subjects reporting pain indicated their average pain was of moderate to severe intensity (average pain rated as > or =5). Using Von Korff's Chronic Pain Grade classification system, the majority of subjects who reported pain fell into either grade I (low disability, low pain intensity; 51%) or grade II (low disability, high pain intensity; 39%). Subjects reported many factors that exacerbate pain (eg, stress or weather) or decrease it (eg, exercise or rest). CONCLUSIONS: The data suggest that pain is common in adults with CP. In many subjects, pain levels were moderate to intense.

Activities of Daily Living↗
PubMed1999

Is a strategy of intended incomplete percutaneous transluminal coronary angioplasty revascularization acceptable in nondiabetic patients who are candidates for coronary artery bypass graft surgery? The Bypass Angioplasty Revascularization Investigation (BARI).

OBJECTIVES: Our objective was to determine whether a strategy of intended incomplete percutaneous transluminal coronary angioplasty revascularization (IR) compromises long-term patient outcome. BACKGROUND: Complete angioplasty revascularization (CR) is often not planned nor attempted in patients with multivessel coronary disease, and the extent to which this influences outcome is unclear. METHODS: Before randomization, in the Bypass Angioplasty Revascularization Investigation, all angiograms were assessed for intended CR or IR via angioplasty. Outcomes were compared among patients with IR intended if assigned to angioplasty, randomized to coronary artery bypass graft surgery (CABG) versus angioplasty; and within angioplasty patients only, among patients with IR versus CR intended. RESULTS: At 5 years, there was a trend for higher overall (88.6% vs. 84.0%) and cardiac survival (94.5% vs. 92.1%) in CABG versus angioplasty patients with IR intended. The excess mortality in angioplasty patients occurred solely in diabetic subjects; overall and cardiac survival were similar among nondiabetic CABG and angioplasty patients. Freedom from myocardial infarction (MI) at 5 years was higher in nondiabetic CABG versus angioplasty patients (92.4% vs. 85.2%, p = 0.02), vet was similar to the rate observed (85%) in nondiabetic CABG and angioplasty patients with CR intended. Five-year rates of death, cardiac death, repeat revascularization and angina were similar in all angioplasty patients with IR versus CR intended. However, a trend for greater freedom from subsequent CABG was seen in CR patients (70.3% vs. 64.0%, p = 0.08). CONCLUSIONS: Intended incomplete angioplasty revascularization in nondiabetic patients with multivessel disease who are candidates for both angioplasty and CABG does not compromise long-term survival; however, subsequent need for CABG may be increased with this strategy. Whether the risk of long-term MI is also increased remains uncertain.

Aged↗
PubMed1999

Rationing decisions: from diversity to consensus.

As rationing decisions become more of an immediate reality for healthcare practitioners it is important to design mechanisms that facilitate carefully deliberated outcomes. No individual can be expected to be able to cover wide debate on their own, so an exercise has been designed that helps generate consensus decisions from diverse opinions. The exercise was piloted with two groups, an undergraduate medical class and the members of a general practice. Though the aims were different for each group, the tool was useful to both for producing the desired outcomes. Expert and non-expert knowledge were drawn upon and rationing prioritisation lists regarding funding of infertility treatment were generated. A description of the exercise and the results produced by the two groups are provided, as well as the theoretical placement for the significance of forming consensus from diversity.

Consensus↗
PubMed1999

Impact of guidelines implemented in a paris university hospital: application to the use of antiemetics by cancer patients.

AIMS: To assess the impact with time of guidelines on antiemetic use in an 850-bed Paris university hospital with a high proportion of cancer patients. METHODS: Guidelines on the use of antiemetics available in cancer chemotherapy were drafted according to the Delphi technique. Their implementation was based upon a patient-specific antiemetic prescription form. To assess the impact of guideline implementation over time, discrepancies between current practice and the guidelines were compared before guideline implementation (between March and August 1995) and after implementation (between March and August 1997, and March and August 1998). RESULTS: Before the Delphi panel's guidelines were implemented, 5-HT3 antagonists were inappropriately administered in 70% of cases. After guideline implementation, this proportion dropped significantly (P<0.0001, Fisher's exact test) to 22% between March and August 1997 and 28% between March and August 1998. CONCLUSIONS: Implementation of guidelines seems to have resulted in significant changes with time, although a causal relationship has not been demonstrated. The development of guidelines by our hospital's multidisciplinary working group helped the various consultants to adjust medical practices to take account of these changes.

Academic Medical Centers↗
PubMed1999

The basic-helix-loop-helix protein pod1 is critically important for kidney and lung organogenesis.

Epithelial-mesenchymal interactions are required for the development of all solid organs but few molecular mechanisms that underlie these interactions have been identified. Pod1 is a basic-helix-loop-helix (bHLH) transcription factor that is highly expressed in the mesenchyme of developing organs that include the lung, kidney, gut and heart and in glomerular visceral epithelial cells (podocytes). To determine the function of Pod1 in vivo, we have generated a lacZ-expressing null Pod1 allele. Null mutant mice are born but die in the perinatal period with severely hypoplastic lungs and kidneys that lack alveoli and mature glomeruli. Although Pod1 is exclusively expressed in the mesenchyme and podocytes, major defects are observed in the adjacent epithelia and include abnormalities in epithelial differentiation and branching morphogenesis. Pod1 therefore appears to be essential for regulating properties of the mesenchyme that are critically important for lung and kidney morphogenesis. Defects specific to later specialized cell types where Pod1 is expressed, such as the podocytes, were also observed, suggesting that this transcription factor may play multiple roles in kidney morphogenesis.

Alleles↗
PubMed1999

Cyclosporin-induced hypertension: incidence, pathogenesis and management.

Blood pressure increases soon after administration of immunosuppressive regimens using cyclosporin. Characteristic vascular changes lead to systemic and renal vasoconstriction. Changes in blood pressure are commonly associated with disturbed circadian regulation and may promote the rapid development of target organ injury, including intracranial haemorrhage, left ventricular hypertrophy and microangiopathic haemolysis. The mechanisms underlying this disorder are complex and include altered vascular endothelial function. Vasodilators such as prostacyclin and nitric oxide are suppressed, whereas vasoconstrictors, including endothelin, are increased. Changes in the kidney include vasoconstriction, reduced glomerular filtration and sodium retention. Effective therapy depends upon rigorous blood pressure control by administration of vasodilating agents, with attention to potential interactions with cyclosporin.

Animals↗
PubMed1999

Coronary vasospasm as a cause of angina following interventional recanalization.

Angina following a coronary intervention may be due to vasospasm rather than restenosis. Two cases of angina following a previously successful recanalization are described. In both cases vasospasm was documented as the cause of angina, determined in one case by using an ergonovine provocative test and in the other by using lesion response to nitroglycerine. Rather than another intervention, vasodilator treatment was instituted, with effective symptom amelioration.

Angina Pectoris↗
PubMed1999

Effect of a single bolus of intracoronary basic fibroblast growth factor on perfusion in an ischemic porcine model.

Basic fibroblast growth factor (bFGF) has been shown to induce angiogenesis in various animal models, but the methods of administration used experimentally are not clinically feasible. The objective of this study was to determine whether a single intracoronary bolus injection of bFGF would improve coronary perfusion in a porcine ischemic model that mimics clinical chronic ischemia. A copper coil studded with gold was delivered into the proximal right coronary artery of juvenile Yorkshire pigs and deployed by interventional techniques. After a four-week interval for stenosis maturation, bFGF (100 micrograms) was administered by bolus injection into the left coronary artery in five animals, and vehicle alone was administered in four animals. Angiogenesis and change in right coronary perfusion area were assessed two weeks later by angiography, myocardial contrast echocardiography and immunohistochemistry. The right coronary perfusion area increased significantly after treatment in all but one of the animals that received bFGF but not in any of the controls. Intimal hyperplasia was not induced by bFGF. Capillary density determined histochemically was not different in the two groups. In conclusion, in a porcine ischemic model, bFGF administered by a single bolus intracoronary injection into the contralateral artery improved antegrade perfusion into the ischemic territory although without histological evidence of angiogenesis. This preliminary work merits further investigation.

Animals↗
PubMed1999

[Malignant melanoma on primary acquired conjunctival melanosis].

A primary acquired melanosis occurred in the right bulbar conjunctiva of a 65 year-old caucasian woman. After four years of steadiness, this lesion gave raise to a malignant conjunctival melanoma. The evolution remained under control three years after the end of the therapeutic procedures. Clinical and histopathological data are presented.

Aged↗
PubMed1998

Opposite phenotypes of hypomorphic and Y766 phosphorylation site mutations reveal a function for Fgfr1 in anteroposterior patterning of mouse embryos.

Intercellular communication is needed for both the generation of the mesodermal germ layer and its division into distinct subpopulations. To dissect the functions of fibroblast growth factor receptor-1 (FGFR1) during mouse gastrulation as well as to gain insights into its possible roles during later embryonic development, we have introduced specific mutations into the Fgfr1 locus by gene targeting. Our results show functional dominance of one of the receptor isoforms and suggest a function for the autophosphorylation of site Y766 in the negative regulation of FGFR1 activity. Y766F and hypomorphic mutations in Fgfr1 generate opposite phenotypes in terms of homeotic vertebral transformations, suggesting a role for FGFR1 in patterning the embryonic anteriorposterior axis by way of regulation of Hox gene activity.

Alleles↗
PubMed1998

The tumor suppressor gene Smad4/Dpc4 is required for gastrulation and later for anterior development of the mouse embryo.

Mutations in the SMAD4/DPC4 tumor suppressor gene, a key signal transducer in most TGFbeta-related pathways, are involved in 50% of pancreatic cancers. Homozygous Smad4 mutant mice die before day 7.5 of embryogenesis. Mutant embryos have reduced size, fail to gastrulate or express a mesodermal marker, and show abnormal visceral endoderm development. Growth retardation of the Smad4-deficient embryos results from reduced cell proliferation rather than increased apoptosis. Aggregation of mutant Smad4 ES cells with wild-type tetraploid morulae rescues the gastrulation defect. These results indicate that Smad4 is initially required for the differentiation of the visceral endoderm and that the gastrulation defect in the epiblast is secondary and non-cell autonomous. Rescued embryos show severe anterior truncations, indicating a second important role for Smad4 in anterior patterning during embryogenesis.

Alleles↗
PubMed1998

Acute coronary artery occlusion likely due to thrombus occurring during coronary angiography: report of a case.

Twenty-five years ago, fatalities due to acute thrombotic coronary occlusion occurring during coronary angiography were reported not infrequently, but are thought to have been eliminated by changes in technique and equipment. We present a case with documentation of a normal coronary arterial tree just before the time of an abrupt occlusion, which had the angiographic features of clot. The likely source of the thrombus was the arterial sheath. Measures for prevention of this complication are discussed.

Aged↗
PubMed1998

A preliminary comparative treatment planning study for radiotherapy of age-related maculopathy.

PURPOSE: We present a comparative planning of different approaches for external radiotherapy in age-related maculopathies. MATERIALS AND METHODS: Calculated dose distributions and dose-volume histograms for (a) bilateral irradiation with 6 MV photons, (b) a single lateral-oblique beam using either photons, electrons or protons and (c) an anterior circular proton beam. RESULTS: For lateral photon or electron beams the dose to the lens is usually lower than 10% of the dose to the macula. The entrance doses for bilateral photon beams are about 50% which increase up to 100% at the orbital bone. About 5 mm of optic nerves are irradiated at the maximal dose while the optic chiasma is spared. A single photon beam gives 50% of the dose to the fellow eye. The electron beam spares the fellow eye but gives a rather inhomogeneous dose to the target volume. For a lateral proton beam, 4 mm of optic nerve receives 90% of the dose, the skin dose is at least 70% of the dose to the macula and the lens and the fellow eye are spared. An anterior proton beam gives 90% of the dose to 1 mm of optic nerve and the 50% isodose approaches the periphery of the lens. CONCLUSION: Doses to the critical structures can be dramatically diminished for all the techniques by reducing the beam size, but only if very precise set-up techniques are used. Proton beams are an attractive solution, but the impact of such a choice on the use of proton facilities and on the national health system should be carefully evaluated, as well as the risk of radio-induced secondary neoplasias.

Humans↗
PubMed1998

Interobserver Reproducibility and Biological Variability of the Surgicutt II Bleeding Time.

The bleeding time is a readily and easily performed clinical test with immediate results, but there is a degree of subjectivity in its performance and interpretation. We performed a study on 27 volunteers designed to determine the normal range, interobserver reproducibility, and biological variability of the test. Bleeding times in these normal subjects ranged from as low as 129 seconds to as high as 803 seconds. The interobserver variability was 106 seconds (2 standard deviations of the mean of the differences of paired results of repeated measurements), and the coefficient of variation was 18%. For bleeding times taken on the same subjects 6 weeks apart, when the same nurse performed the test at both visits, the difference was 150 seconds (2 standard deviations of the mean of the differences of paired samples) and the coefficient of variation was 27%, and they were essentially the same if a different nurse performed the tests at each visit. There is a wide range in the bleeding times among subjects. However, within individuals there is little biological variability, and most of the difference over time is due to interobserver variability. This suggests that changes in bleeding time are clinically useful in predicting platelet responsiveness in individual patients.

Journal Article↗
PubMed1998

Family systems therapy after Operation Desert Storm with European-theater veterans.

We describe a quasi-experimental trial of time-limited family therapy with veterans and families of veterans who served in Europe, outside the war zone, during Operation Desert Storm (ODS). Family systems therapy was provided both to individuals and conjointly to couples or families during the acute postwar readjustment period. The intervention adapted strategies from structural, strategic, intergenerational, and behavioral family therapies in a brief-treatment protocol for systemic stressor resolution. Veterans given family system therapy were able to resume functional levels of psychosocial adjustment and reduce the risk of long-term (chronic or delayed) psychosocial impairment. Based on these preliminary findings, controlled evaluation of family systems therapy appears warranted for individuals and families exposed to subtraumatic stressors such as wartime non-war-zone military deployment.

Adult↗