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R Evans

Publications and source records attributed to R Evans.

At least 181 records · Page 10Linked to original sources
PubMed1997

Design and methods of the National Cooperative Inner-City Asthma Study.

The National Cooperative Inner-City Asthma Study (NCICAS) was established to identify and then intervene on those factors which are related to asthma morbidity among children in the inner-city. This paper describes the design and methods of the broad-based initial Phase I epidemiologic investigation. Eight research centers enrolled 1,528 children, 4 to 9 years of age, from English- or Spanish-speaking families, all of whom resided in major metropolitan inner-city areas. The protocol included an eligibility assessment and an extensive baseline visit, during which symptom data, such as wheezing, lost sleep, changes in activities of daily living, inpatient admissions, and emergency department and clinic visits were collected. A comprehensive medical history for each child was taken and adherence to the medical regimen was assessed. Access, as well as barriers, to the medical system were addressed by a series of questions including the location, availability, and consistency of treatment for asthma attacks, follow-up care, and primary care. The psychological health of the caretaker and of the child was also measured. Asthma knowledge of the child and caretaker was determined. Sensitization to allergens was assessed by skin-prick allergen testing and exposure to cigarette smoke and the home environment were assessed by questionnaire. For more than a third of the families, in-home visits were conducted with dust sample allergen collection and documentation of the home environment, such as the presence of pets and evidence of smoking, mildew, and roaches. Urine specimens were collected to measure passive smoke exposure by cotinine assays, blood samples were drawn for banking, and children age 6 to 9 years were given spirometric lung function assessment. At 3, 6 and 9 months following the baseline assessment, telephone interviews were conducted to ask about the child's symptoms, unscheduled emergency department or clinic visits, and hospitalizations. At this time, peak flow measurements with 2-week diary symptom records were collected.

Allergens↗
PubMed1997

Characteristics of inner-city children with asthma: the National Cooperative Inner-City Asthma Study.

Asthma morbidity has increased dramatically in the past decade, especially among poor and minority children in the inner cities. The National Cooperative Inner-City Asthma Study (NCICAS) is a multicenter study designed to determine factors that contribute to asthma morbidity in children in the inner cities. A total of 1,528 children with asthma, ages 4 to 9 years old, were enrolled in a broad-based epidemiologic investigation of factors which were thought to be related to asthma morbidity. Baseline assessment included morbidity, allergy evaluation, adherence and access to care, home visits, and pulmonary function. Interval assessments were conducted at 3, 6, and 9 months after the baseline evaluations. Over the one-year period, 83% of the children had no hospitalizations and 3.6% had two or more. The children averaged 3 to 3.5 days of wheeze for each of the four two-week recall periods. The pattern of skin test sensitivity differed from other populations in that positive reactions to cockroach were higher (35%) and positive reactions to house dust mite were lower (31%). Caretakers reported smoking in 39% of households of children with asthma, and cotinine/creatinine ratios exceeded 30 ng/mg in 48% of the sample. High exposure (> 40 ppb) to nitrogen dioxide was found in 24% of homes. Although the majority of children had insurance coverage, 53% of study participants found it difficult to get follow-up asthma care. The data demonstrate that symptoms are frequent but do not result in hospitalization in the majority of children. These data indicate a number of areas which are potential contributors to the asthma morbidity in this population, such as environmental factors, lack of access to care, and adherence to treatment. Interventions to reduce asthma morbidity are more likely to be successful if they address the many different asthma risks found in the inner cities.

Allergens↗
PubMed1997

Psychosocial characteristics of inner-city children with asthma: a description of the NCICAS psychosocial protocol. National Cooperative Inner-City Asthma Study.

Previous research has demonstrated a significant reciprocal relationship between psychosocial factors and asthma morbidity in children. The National Cooperative Inner-City Asthma Study investigated both asthma-specific and non-specific psychosocial variables, including asthma knowledge beliefs and management behavior, caregiver and child adjustment, life stress, and social support. This article presents these psychosocial characteristics in 1,528 4-9-year-old asthmatic urban children and their caretakers. Caretakers demonstrated considerable asthma knowledge, averaging 84% correct responses on the Asthma Information Quiz. However, respondents provided less than one helpful response for each hypothetical problem situation involving asthma care, and most respondents had more than one undesirable response, indicating a potentially dangerous or maladaptive action. Both adults and children reported multiple caretakers responsible for asthma management (adult report: average 3.4, including the child); in addition, children rated their responsibility for self-care significantly higher than did adults. Scores on the Child Behavior Checklist indicated increased problems compared to normative samples (57.3 vs. 50, respectively), and 35% of children met the criteria for problems of clinical severity. On the Brief Symptom Inventory, adults reported elevated levels of psychological distress (56.02 vs norm of 50); 50% of caretakers had symptoms of clinical severity. Caretakers also experienced an average of 8.13 undesirable life events in the 12 months preceding the baseline interview. These findings suggest that limited asthma problem-solving skills, multiple asthma managers, child and adult adjustment problems, and high levels of life stress are significant concerns for this group and may place the inner-city children in this study population at increased risk for problems related to adherence to asthma management regimens and for asthma morbidity.

Adult↗
PubMed1997

The Jarvik 2000 Oxford system: increasing the scope of mechanical circulatory support.

METHODS: We developed a system for mechanical circulatory support based on the Jarvik 2000 intraventricular axial flow impeller pump (Jarvik Research, Inc., New York, N.Y.) and percutaneous electric power. The adult pump provides flow at a rate up to 10 L/min with an energy requirement of 7 to 10 watts. The device was implanted into the apex of the left ventricle through a left thoracotomy without cardiopulmonary bypass. A Dacron graft conveyed blood to the descending thoracic aorta. In patients, we will use a skull-mounted carbon pedestal to transmit fine electric wires through the scalp skin. Being highly vascular, the scalp skin is resistant to infection. RESULTS: We tested 16 adult systems and one pediatric system in 17 adult ewes weighing between 60 and 90 kg. Five died of perioperative complications. Twelve survived between 3 and 198 days (mean 44 days) with a functioning device. None of the sheep could receive adequate anticoagulation with warfarin (INR 1.0 to 1.5). Acute thrombotic occlusion occurred after a 3-hour power loss in one device (46 days) but was cleared with streptokinase. In a second animal with endocarditis, the pump inflow became occluded with vegetations. No other device-related problems or important hemolysis developed despite pump speeds between 10,000 and 18,000 rpm. Renal function remained normal in all animals. Autopsy studies showed no pannus ingrowth at the device inflow despite the restrictive left ventricular cavity size. No sign of thromboembolism could be detected in the brains or kidneys. CONCLUSION: Our findings indicate the Jarvik 2000 Oxford System to be a safe and effective circulatory assist device. Potential uses include permanent circulatory support, bridge to transplantation, or bridge to myocardial recovery in acute or chronic left ventricular failure.

Animals↗
PubMed1997

Effect of a centralizing device on cement mantle deficiencies and initial prosthetic alignment in total hip arthroplasty.

Sixty consecutive patients undergoing a primary hybrid total hip arthroplasty were randomized to receive a femoral component either with or without a distal centralizing device. The group with a centralizer had significantly fewer patients with cement mantle deficiencies (excessively thin areas of cement) than the group without a centralizer (P < .001). Furthermore, the centralizer group was, on average, in a neutral alignment, whereas the group without a centralizer was in a varus alignment (P < .001). It was concluded that the distal centralizing device significantly decreases the incidence of cement mantle deficiences and reproducibly aids in achieving a more neutral prosthetic alignment.

Bone Cements↗
PubMed1997

Bioactive iridoids and a new lignan from Allamanda cathartica and Himatanthus fallax from the Suriname rainforest.

Bioassay-guided fractionation of the EtOAc extract of both Allamanda cathartica and Himatanthus fallax (Apocynaceae) using the Sc-7 yeast strain resulted in the isolation of the weakly cytotoxic isoplumericin and plumericin. In addition, the new lignan 7(R)-methoxy-8-epi-matairesional and three known compounds, plumieride, matairesinol, and pinoresinol, were isolated from H. fallax.

Animals↗
PubMed1997

Treatment of recurrent malignant glioma with BCNU-fluosol and oxygen inhalation. A phase I-II study.

OBJECTIVES: To evaluate the toxicity and response rate following BCNU with oxygen inhalation and escalating dosages of fluosol administered to patients with radiographic progression of malignant glioma after definitive surgery and radiotherapy. METHOD: This single arm, phase I-II multicenter trial, enrolled 99 patients with malignant gliomas recurrent after definitive surgery and radiotherapy. All patients received a fixed dose (200 mg/m2) of BCNU along with 100% oxygen and fluosol, a perfluorochemical. Fluosol doses were escalated between patients (150, 275, 400 and 600 ml/m2). Treatment was repeated every 6 weeks for a maximum of 6 cycles. Patients were assessed for toxicity at the time of infusion and sequentially thereafter. Response was evaluated clinically and radiologically at least every 6 weeks. RESULTS: Treatment was well tolerated. Dose reductions were required at least once in 18 patients, treatment delays were necessary at least once in 33 patients. Grade 3-4 leukopenia occurred in 6 patients (12 events), grade 3-4 thrombocytopenia in 10 patients (25 events) and grade 3-4 liver enzymes elevations in 18 patients (31 events). Higher fluosol dosages did not produce increases in toxicity or responses. Response or stabilization was seen in 57% (38% were stabilizations) of the patients who entered the trial with progressive disease. The median time to progression was 45 weeks, and median survival was 66 weeks for patients who had response or stabilization. For patients with glioblastoma response/stabilization was seen in 45% with a mean duration of 24 weeks, for patients with anaplastic astrocytoma response/stabilization was seen in 68% with a mean duration of 50 weeks. CONCLUSION: This treatment regimen is well tolerated. Our results suggest fluosol may enhance the effectiveness of BCNU for the treatment of recurrent malignant gliomas. Future studies will be performed using fluosol at the dose of 400 ml/m2.

Adolescent↗
PubMed1997

Beneficial effect of concomitant administration of isoflurane and nicorandil.

In common with halogenated anaesthetics, nicorandil, a new KATP channel opener, has been shown to have cardioprotective and vasodilator effects. Recent studies have also suggested that the vasodilator and protective effects of halogenated anaesthetics are mediated partly via KATP channel opening. This study examined the effects of concurrent administration of nicorandil and isoflurane on haemodynamic state and ventricular function before, during and after 15 min of ischaemia. We studied left ventricular function in 40 anaesthetized rabbits using ultrasonomicrometry. Measurements were obtained before, during and after 15 min of regional ischaemia. Regional ventricular function was assessed in terms of systolic shortening (SS%) and preload recruitable work area (PRWA, the area beneath the regional stroke work vs end-diastolic length relationship) during reperfusion. Four groups were studied: group F (n = 10) received a bolus dose of fentanyl 100 micrograms kg-1 and then 400 micrograms kg-1 h-1 throughout; group 1 (n = 10) received 2.05% end-tidal concentration of isoflurane (1 MAC); group FN (n = 10) received fentanyl, a bolus does of nicorandil 100 micrograms kg-1 and then 25 micrograms kg-1 min-1, 15 min before occlusion; and group IN (n = 10) received isoflurane and nicorandil. Isoflurane decreased left ventricular systolic pressure and ventricular contractility (+dP/dtmax, slope of preload recruitable stroke work, and SS%). Nicorandil increased -dP/dtmax in group FN. Post-ischaemic regional left ventricular contractility in group I did not differ from that in group F, however, groups receiving nicorandil recovered to a greater extent. Group IN showed better recovery compared with all other groups when ventricular contractility was assessed by PRWA normalized to pre-occlusion values (mean 99.3 (SEM 10.5)% vs 73.4 (7.5)%, 50.2 (5.8)% and 52.4 (3.7)% at 120 min reperfusion in groups FN, I and F, respectively). Tissue ATP and lactate contents did not differ between groups. We conclude that concurrent administration of nicorandil and isoflurane enhanced post-ischaemic recovery compared with isoflurane anaesthesia or nicorandil and fentanyl administration.

Adenosine Triphosphate↗
PubMed1997

The analgesic efficacy of ibuprofen in periodontal surgery: A multicentre study.

The efficacy of a non-steroidal anti-inflammatory agent, ibuprofen, was evaluated in pain control following periodontal surgery. This type of agent acts peripherally by inhibiting the release of prostaglandins and minimizing the local inflammatory response. Thus there may be an advantage in pre-treatment administration of the drug so as to delay or even prevent postoperative pain. The study was multicentre, involving a Public Hospital Periodontal Unit, two specialist periodontal practices in Sydney, NSW, and two in Canberra, ACT. One hundred and twenty-seven patients who were to undergo periodontal surgery were randomly given either two 200 mg tablets of ibuprofen or two matching placebo tablets at least 30 minutes before administration of local anaesthesia. The procedure was double blind: neither the patient nor the clinician was aware of the tablet identity. Postoperatively, all patients were given labelled ibuprofen for pain relief, but were randomly divided into two groups: As directed who were instructed to take the drug regularly for two days postoperatively, and As required, who were to take the drug only if needed for pain relief. All patients completed a diary recording quantity and time of medication, and regular assessment of pain experience utilizing a visual analogue scale. The As directed group showed no significant difference in pain experience between pre-operative and post-operative only medication, but the As required group experienced significantly less pain and requirement for medication if the ibuprofen was administered pre-operatively.

Adolescent↗
PubMed1997

Selective serotonin reuptake inhibitors in older patients. A tolerability perspective.

Depression is a serious illness that is common in the elderly but which is frequently overlooked. Management is complicated by physiological changes associated with aging, the presence of comorbid physical illness, and compliance problems; these factors must be taken into account when selecting an appropriate antidepressant. The well known problems associated with the tricyclic antidepressants (TCAs) [i.e. their unwanted anticholinergic, adrenergic and histaminergic effects], which are troublesome in younger patients, can have serious consequences for elderly depressed patients. The TCAs can cause symptoms that worsen concomitant physical illness, which is frequently present in the elderly, and their cardiotoxicity in overdose is of concern in both younger and older patients. The selective serotonin (5-hydroxytryptamine; 5-HT) reuptake inhibitors have been shown to be as efficacious as the TCAs in the general depressed population, but to lack the anticholinergic adverse effects and cardiotoxicity associated with those drugs. Their increased safety and tolerability makes them a preferred treatment for depressed elderly patients.

Aged↗
PubMed1997

Role of tumor necrosis factor-alpha in the spontaneous development of pulmonary fibrosis in viable motheaten mutant mice.

The viable motheaten mutant mouse is severely immunodeficient and dies from a naturally occurring progressive pulmonary inflammation at approximately 10 weeks of age. The pulmonary disease is characterized by excessive macrophage accumulation in the lung and fibrosis. We correlated the development of lung injury in viable motheaten mice with tumor necrosis factor-alpha (TNF-alpha) levels in serum and lung. Significantly increased serum TNF-alpha levels were observed by enzyme-linked immunosorbent assay in viable motheaten mice at 4, 6, and 10 weeks of age as compared with normal control littermate mice. These ages correlated well with observed changes in lung wet weights, lung collagen content, and histological evidence of pulmonary inflammation and fibrosis. Qualitative assessment of lung tissue TNF-alpha levels was performed by immunohistochemical staining using immunoperoxidase techniques. These studies revealed increased levels of TNF-alpha in macrophage-like cells in viable motheaten mice from 5 to 10 weeks of age as compared with littermate control animals. Alveolar macrophages isolated from viable motheaten mice produced significantly greater amounts of TNF-alpha when stimulated with lipopolysaccharide compared with alveolar macrophages from control animals. In addition, administration of anti-TNF-alpha antibody to motheaten bone marrow recipient mice decreased the severity of acute lung injury. The results demonstrate a close correlation between the development of pulmonary injury and TNF-alpha levels in this model of spontaneously developing fibrotic lung disease.

Animals↗
PubMed1996

Differential sensitivity of mouse mononuclear phagocytes to CSF-1 and LPS: the potential in vivo relevance of enhanced IL-6 gene expression.

In this report, we compared the responsiveness of subpopulations of mononuclear phagocytes (MNP) to the actions of the monocyte-macrophage colony-stimulating factor (CSF-1) and lipopolysaccharide (LPS), as measured by the expression of the IL-6 (Il6) gene. It was seen that neither monocytes nor elicited peritoneal macrophages (PMphi) responded directly to CSF-1 compared with resident PMphi that were induced to express high levels of Il6 mRNA and release IL-6 protein. Resident PMphi released basal (constitutive) amounts of IL-6, while constitutive release by monocytes and elicited PMphi was barely detectable. Monocytes and elicited PMphi expressed similar levels of sensitivity to LPS, as measured by IL-6 release, and were less reactive than resident PMphi. When CSF-1 and LPS were added simultaneously to resident PMphi, a dose-dependent synergistic release of IL-6 was seen. Elicited PMphi also responded synergistically but required higher levels of CSF-1 and LPS, while monocytes failed to respond synergistically under any conditions. A similar synergistic effect was also seen in vivo when mice were injected with CSF-1 and LPS. Under these conditions, only resident peritoneal cells were shown to release IL-6 ex vivo while blood leukocytes and spleen cells released minimal amounts. These findings indicate that the stage of differentiation/maturation of MNP may be important for the ability of CSF-1 to render the cells sensitive to secondary stimulation, such as by LPS, and determines to what extent MNP subpopulations contribute to inflammatory responses in vivo.

Animals↗
PubMed1996

The use of sonography in differentiating cervical lymphomatous lymph nodes from cervical metastatic lymph nodes.

Lymphoma and metastases are common causes of cervical lymphadenopathy. Clinical examination alone is unable to differentiate the two. Ultrasound (US) with its high sensitivity and specificity when combined with a find needle aspiration cytology (FNAC) is therefore the ideal initial investigation. We present the spectrum of findings in 19 patients with non Hodgkins lymphoma (NHL), 15 patients with pharyngeal, laryngeal and oesophageal (PLO) carcinomas, 22 patients with oral cavity tumours and 12 patients with infraclavicular carcinomas. The US features found consistently useful in differentiating NHL from other metastases were the distribution of the nodes, distal enhancement and lack of intranodal necrosis. Other US features of abnormal nodes helped identify abnormality but did not help in differentiation.

Adolescent↗
PubMed1996

An unusual source for an outbreak of methicillin-resistant Staphylococcus aureus on an intensive therapy unit.

During a four-month period, six patients on an intensive therapy unit became colonized or infected with methicillin-resistant Staphylococcus aureus (MRSA). Four of these patients were colonized by the Epidemic MRSA strain 15 (EMRSA 15). The outbreak was characterized by the fact that all four of these patients were nursed in the same bed on the unit before acquisition of the organism. Investigation of the outbreak led the authors to believe that the source of the MRSA may have been the exhaust ducting of the adjacent isolation room ventilation system which allowed the organisms to enter the unit via a partially open window positioned above that particular bed. The cycle was broken once the ventilation system was repaired and the window above the bed was properly sealed.

Aged↗
PubMed1996

Perioperative management for childhood asthma.

BACKGROUND: Children with asthma have been reported to be at increased risk for intraoperative bronchospasm. Current medical literature focuses on this problem in adult patients. This is a report of our experience in children. OBJECTIVE: The purpose of this study was to discern whether children with reactive airways disease (asthma) actually had a high likelihood of perioperative bronchospasm as the medical literature suggests. METHODS: A retrospective chart review of 386 asthmatic children and 51 with bronchopulmonary dysplasia seen perioperatively between 1987 and 1992 was instituted. Children with asthma were classified as mild, moderate or severe based on the number of hospitalizations, emergency room visits, intensive care unit admissions and medications at the time of evaluation. Patients with bronchopulmonary dysplasia were included in a separate category. Individualized asthma management was recommended for all patients in preparation for surgery. Blood gases, chest radiographs and pulmonary function studies were not routinely ordered. RESULTS: Only 3 of 437 children in a five-year period (0.13%) had intraoperative bronchospasm, easily controlled with the use of beta-2 agonists. CONCLUSIONS: This study demonstrates that asthmatic children appropriately prepared for surgery do not appear to have an increased risk for adverse outcome. The children treated with more than inhaled beta-2 agonists were those who had more severe asthma, recent viral infection, recent exacerbation of asthma, or recent hospitalization for asthma.

Adrenergic beta-Agonists↗