Biomedical subjects

G J Beck

Publications and source records attributed to G J Beck.

At least 55 records · Page 3Linked to original sources

PubMed1988

Uncontrolled trial of cryofiltration in rheumatoid arthritis.

In an open trial of cryofiltration in rheumatoid arthritis at our institution, 19 patients received 464 treatments; the intensive schedule of ten treatments in 5 weeks was completed in 14 of the 19, and excellent to good clinical response was achieved in ten of these. The combined results demonstrated significant reductions in Ritchie index, morning stiffness, and 50-foot-walk time in the intensive treatment period, as well as significant increases in hand grip strengths. In the maintenance treatment period treatment frequency was individually selected and at less frequent intervals. Changes in clinical parameters were notably less. Although significant correlations were observed between the percent change in clinical parameters and the percent change in biochemical and hematological parameters, no consistent pattern was found. The favorable results of this trial and other uncontrolled trials has led to a two-center double-blind controlled trial of cryofiltration in rheumatoid arthritis that is now in progress.

Adult↗

PubMed1988

The effect of antenatal surgery on postnatal palatal growth in sheep.

It has been suggested that repair of skin and mucosal wounds carried out in animals in utero leaves little or no trace of the operative procedure when examined at birth. This study examined the palates of lambs affected surgically in utero postnatally for scarring and transverse palatal growth. Nineteen pregnant sheep were affected at 120 days gestation. Surviving lambs followed for 6 months demonstrated altered palatal morphology.

Animals↗

PubMed1988

Comparison of pneumatic retinopexy with alternative surgical techniques.

To determine the efficacy of pneumatic retinopexy, the authors conducted a retrospective study of 56 cases of uncomplicated retinal detachments (RDs) treated with this technique (follow-up, 6-18 months). These were compared with 28 similar cases treated with a Lincoff balloon and 78 similar cases treated with a scleral buckle. The long-term success rates for these three groups were 71, 64, and 96%, with the incidence of new breaks being 20, 18, and 1.3% respectively. In aphakic or pseudophakic patients with an absent or ruptured posterior capsule, the success rate for pneumatic retinopexy was only 43%. In phakic and aphakic patients with an intact posterior capsule, the success rate for pneumatic retinopexy improved to 81%. These data suggest that this technique is less effective in aphakic or pseudophakic patients with an absent or ruptured posterior capsule and that careful follow-up to detect new breaks is necessary in all cases. A prospective randomized study is needed to verify these data.

Air↗

PubMed1988

Serum Lp(a) level as a predictor of vein graft stenosis after coronary artery bypass surgery in patients.

Although the serum lipoprotein fraction Lp(a) has been associated with coronary artery atherosclerosis, its relationship to narrowing of saphenous vein grafts has not previously been elucidated. We therefore measured serum Lp(a) levels in 167 symptomatic patients undergoing cardiac catheterization who had had coronary artery bypass surgery 0.7 to 14.3 years earlier. Lp(a), total cholesterol, and total triglyceride levels were compared with the degree of saphenous vein graft stenosis to test for any association. Serum Lp(a) levels were significantly associated with the degree of stenosis of saphenous vein grafts (r = .24, p = .002). Mean Lp(a) levels (mg/dl) in the 135 patients with stenosis were almost double (32.0 +/- 32.7, mean +/- SD) those in the 32 patients with no graft stenosis (16.7 +/- 22.6; p = .002). Graft stenosis was not associated with previous myocardial infarction, hypertension, obesity, diabetes, or smoking. Serum cholesterol levels (mg/dl) were slightly higher in the stenosis group (251.3 +/- 69) than in the no-stenosis group (231.8 +/- 48.8), but the difference was of borderline significance (p = .06). A stepwise increase in mean Lp(a) was found in groups of patients with increasing vein graft stenosis. At a serum Lp(a) level of 31.6 mg/dl or above, 92% of the patients demonstrated vein graft stenosis. Thus, patients with elevated Lp(a) levels have an increased risk of developing saphenous vein graft stenosis after coronary bypass surgery.

Cardiac Catheterization↗

PubMed1988

Bronchial responsiveness after inhalation of cotton bract extract.

This study examined nonspecific airway responsiveness to methacholine (MC) after inhalation of cotton bract extract (CBE). In a randomized double-blind, crossover trial, 13 healthy volunteers underwent an MC inhalation challenge test prior to inhalation of CBE and normal saline solution (NSS) aerosol sham as well as 2, 8, 24, and 168 h (7 days) later. The response parameter was the concentration of MC required to induce a 25% decrement in the maximal expiratory flow at 40% of the vital capacity below total lung capacity on the partial expiratory flow-volume curve (PC25MEF40%(P]. Five of 13 subjects demonstrated a ventilatory response to CBE with a 20% or larger decrement in the MEF40%(P); no subject demonstrated such change with NSS. For the group, the maximal decrement in MEF40%(P) was to 76.5 +/- 20.3% of baseline (mean +/- SD), occurring approximately 60 to 90 min after provocation, whereas the largest decrement after normal saline was to 88 +/- 10.6% of baseline, occurring immediately after inhalation. Changes in airway responsiveness to MC were transient. For example, the PC25MEF40%(P) for the group (mean +/- SD) was 51.3 +/- 41.1 mg/ml at baseline and 25.8 +/- 30.3 and 52.2 +/- 57.3 mg/ml at 2 and 8 h. After a pre-sham baseline of 50.4 +/- 43.2 mg/ml, PC25MEF40%(P) was 57.6 +/- 83.8 and 153.8 +/- 148 mg/ml at 2 and 8 h. Repeated measures ANOVA on these acute, same-day changes (i.e., 2 and 8 h after provocation) demonstrated a statistically significant effect of CBE on airway responsiveness (p = 0.048). These data demonstrate that inhalation of CBE, in addition to bronchospasm, causes a transient increase in airway responsiveness.

Administration, Inhalation↗

PubMed1988

The shape of the maximum expiratory flow volume curve.

Differences in the shape of the maximum expiratory flow volume (MEFV) curve have been associated with pathologic states and physiologic differences between normal individuals. We describe variations in a new parameter, angle beta, which characterizes the general configuration of the MEFV curve among healthy subjects and subjects with disease in 5,140 white individuals. Women had consistently larger beta angles than men. There was a progressive decline in beta with advancing age. Cigarette smokers had lower beta angles than did lifetime never-smokers. Subjects with abnormal lung function patterns had lower beta angles than individuals with a normal pattern. Finally, individuals with asthma, chronic bronchitis, dyspnea and wheezing had significantly lower beta angles than healthy individuals. Further clinical and epidemiologic studies are needed to evaluate this measurement's possible value in pulmonary function evaluation.

Adolescent↗

PubMed1987

Thyrotropin-releasing hormone (TRH) in murine motor neuron disease (the wobbler mouse).

Clinical benefits of thyrotropin-releasing hormone (TRH) were tested in wobbler mice, an animal model of motor neuron disease. After the disease was clinically recognized at 3-4 weeks, the animals were divided into two groups, each group consisting of 5 pairs of wobbler mice and normal littermates. TRH (50 mg/kg) and normal saline (NS) were injected intraperitoneally daily, 6 times per week for 9 weeks, in a double-blind study. Weekly assessments consisted of front paw grip strength, push walking, body weight, and semiquantitative grading. At the end of the trial, the brain and spinal cord were sampled to measure TRH and cyclo (His-Pro) concentrations. Progression of motor neuron disease was evident in wobbler mice, regardless of treatment. Descriptive semiquantitative gradings showed the tendency of improvement in TRH-treated wobbler mice. In saline-injected controls, TRH levels in the cervical spinal cord were significantly increased (P less than 0.01) in wobbler mice compared to littermates. However, with TRH treatment, there was no significant difference in TRH and cyclo (His-Pro) levels in any neural tissue between wobbler and controls. The lack of clinical benefits with TRH in wobbler mice may be due to increased TRH levels found in diseased spinal cord in murine motor neuron disease.

Amyotrophic Lateral Sclerosis↗

PubMed1987

A study of respiratory effects from exposure to 2.0 ppm formaldehyde in occupationally exposed workers.

It has been suggested that exposure to formaldehyde (FA) induces asthmatic symptomatology. We have previously studied healthy and asthmatic individuals and found that lung function was unaltered by controlled exposures to 2.0 ppm FA with and without mild exercise. Our present study extends these observations to a group of hospital laboratory workers routinely exposed to FA. Fifteen laboratory workers were exposed in double-blind, random sequence to 0 and 2 ppm FA for 40 min in an environmental chamber with temperature and relative humidity held constant at 23 degrees C and 50%, respectively. These exposures were repeated on two more occasions with a 10-min exercise regimen (450 kpm/min) after being in the chamber 5 min. In addition, a symptom diary and measurements of peak expiratory flow rate (PEFR) were recorded for 24 hr after exposure. Lung function remained unaltered for all 4 exposure days; e.g., mean FEV1.0 for the group did not change by more than 3% at any testing time on any exposure day. Also, there were no delayed obstructive changes as measured by PEFR recordings. Symptoms were mild and transient with unusual odor and eye irritation the most frequent complaint. No lower airway symptoms were reported. We conclude that this group of healthy laboratory workers did not experience any acute or delayed lung function changes from exposure to 2.0 ppm FA at rest and with exercise and that irritative symptoms were few.

Adult↗

PubMed1987

Radical cystectomy for carcinoma of the bladder in the elderly patient.

Between 1979 and 1984, 136 patients underwent radical cystectomy and urinary diversion for the treatment of invasive carcinoma of the bladder. Of the patients 38 were 70 years old or more and they were considered elderly. The mortality rates for those less than 70 compared to those more than 70 years old were 1 and 5 per cent, respectively, and the morbidity rates were 39 and 34 per cent, respectively, with wound separation being the most common complication. There was no statistically significant difference with respect to age in the morbidity or mortality rates. The median hospital stay was 14 days but if a complication occurred the hospital stay was significantly longer. For elderly patients in general good health, radical cystectomy and urinary diversion should not be withheld on the basis of age alone.

Adult↗

PubMed1987

Colectomy with ileorectal anastomosis for familial adenomatous polyposis: the risk of rectal cancer.

One hundred thirty-three patients with familial adenomatous polyposis undergoing colectomy and ileorectal anastomosis have been reviewed for the occurrence of cancer in the rectal stump. Ten patients developed rectal cancer (Actuarial survivorship rate of 88% for those patients free of rectal cancer at 20 years). Potential risk factors for the development of rectal cancer, including age at colectomy, previous colon cancer, number of rectal polyps, and length of the rectal stump, were analyzed and no significant differences were found. A policy of total colectomy with ileorectal anastomosis at 12 to 15 cm with conscientious lifelong follow-up thereafter is advocated for persons affected by familial adenomatous polyposis.

Actuarial Analysis↗

PubMed1987

Improved assessment of bioactive erythropoietin in human sera using a modified tritiated-thymidine-incorporation assay.

The reproducibility and utility of an in vitro bioassay for erythropoietin were evaluated, and modifications, including the use of frozen target cells, were made. The assay, based on 3H-thymidine incorporation into phenylhydrazine-treated mouse spleen cells, showed a dose-response curve from 0.2 to 20 mU of sheep plasma or human urinary erythropoietin, with a 50-100-fold increase in 3H-thymidine incorporation. The dose-response curve, using purified, recombinant erythropoietin was identical to that from material obtained from other sources. The use of frozen cells simplified the methodology, reduced the time for assay preparation, and lowered costs. The freezing process resulted in 15% attrition of the cells, but after one year of storage, this level was not increased nor was the response to erythropoietin diminished. The nonspecificity of the assay was reduced by supplementing the cells with critical nutrients, depleting fetal bovine serum of endogenous erythropoietin, and reducing solute variability by ultrafiltration and reconstitution of samples with culture medium. Heat inactivation diminished inhibitors in sera samples, but affinity chromatography using wheat-germ lectin-Sepharose was most effective for extracting erythropoietin and reducing nonspecific effects. The assay is sensitive, can be used to measure multiple samples rapidly, and should prove useful for complementing immunoassay techniques.

Animals↗

PubMed1986

Colorectal and extracolonic malignancy in ulcerative colitis.

In a review of 1248 cases of ulcerative colitis seen at the Cleveland Clinic that were followed up to 1984 (mean, 14.4 years), 82 patients (6.5%) were subsequently found to have colorectal cancer and 48 (3.8%) had extracolonic malignancy, 6 of them with associated colorectal cancer. Most patients with colorectal cancer were men (2:1), and had extensive (90%) and long-lasting colitis (10 years or more in 93% of cases; mean 18 years). Colitis was inactive before the diagnosis of cancer in 48%. Acute onset of the first attack was rare (7%), and the disease had a remittent course in 92%. The mean age at diagnosis of cancer was 43 years. The cumulative risk of colorectal cancer was significantly higher in patients with extensive colitis than in those with left-sided disease (P less than 0.0001: 11.9% vs. 1.8% at 20 years and 25.3% vs. 3.7% at 30 years). When comparing mean duration of disease, left-sided colitis (22 years) did not differ significantly from extensive disease. The tumor was multifocal in 13.5%, proximal to the splenic flexure in 44%, and poorly differentiated in 34% of the cases. The diagnosis was suspected clinically in 64% of cases. The prognosis of colorectal cancer in patients with ulcerative colitis appears to be similar to that in the general population. The cumulative 5-year survival rate was 54%. This study supports the concept that surveillance colonoscopy should be started after 8 to 10 years of extensive colitis and after 15 years of left-sided colitis. Among those with extracolonic malignancy, the incidence of bile duct carcinoma, leukemia, bone tumors, and endometrial cancer was significantly greater than expected (P less than 0.01), whereas that of lung cancer was significantly lower than expected (P less than 0.01).

Adolescent↗

PubMed1986

Proton magnetic resonance imaging in ischemic cerebrovascular disease.

Proton magnetic resonance imaging (MRI) using a 0.6- or 1.5-Tesla superconductive magnet was compared with high-resolution computed tomography (CT) in 60 patients with transient ischemic attacks (TIAs) or brain infarction. MRI showed focal parenchymal changes in 84% of patients with TIAs, whereas CT showed similar changes in 42%. The sensitivity of MRI was also greater in patients with infarcts, but the difference between CT and MRI was not as great. Infarcts were usually better delineated by MRI regardless of location. However, MRI failed to reveal cortical infarcts that were clearly seen on contrast-enhanced CT scans and was unable to clearly distinguish subacute from chronic hemorrhagic infarcts. MRI changes were best detected with T2-weighted images and usually appeared as multiple areas of increased signal intensity in the subcortical and periventricular white matter. MRI changes often could not be correlated with the clinical history and neurological findings; identical changes have been seen in patients with no history of cerebrovascular disease.

Acute Disease↗

PubMed1986

Discriminating power of measurements from maximum expiratory flow-volume curves.

Maximum expiratory flow-volume curves have been used to characterize normal and abnormal respiratory function. Previous investigators have usually attempted to study whether any single lung function separately is most useful in characterizing lung dysfunction. Using stepwise discriminant analysis we sought to identify which combination of lung function parameters derived from maximum expiratory flow-volume curves could best discriminate between epidemiologic groups defined on the basis of smoking status and presence or absence of respiratory symptoms. We studied 5,031 whites, 2,271 males and 2,760 females, from three communities. In general, combinations of lung functions were no more useful than single lung functions to best discriminate between the groups studied. Flow rates at 50 and 25% of vital capacity remaining to be expired were most often selected as the best discriminating lung function, possibly suggesting obstruction of small airways in the smoking and symptomatic groups.

Adolescent↗

PubMed1986

A study of isoetharine mesylate in patients with chronic bronchial asthma.

We performed a double-blind, random crossover study to investigate the respiratory effects of a single dose isoetharine mesylate (IM), administered by a metered aerosol canister in 19 subjects with mild, stable asthma. In addition, we studied the influence of the dose (number of actuations) and the mode of administration (delay between actuations) on these respiratory effects. The protocol consisted of a screening day and four test days: (1) one inhalation IM (2) two inhalations IM (3) one inhalation placebo (P), and (4) two inhalations P. In addition, the first nine asthmatics paused one minute between inhalations whereas the last ten paused five minutes between inhalations. Lung function was assessed using maximal and partial expiratory flow volume curves. Measurements were taken prior to aerosol delivery and for six hours after aerosol. Significant differences between IM and P were seen for up to two hours. The maximum effect was observed at 15 minutes, corresponding to a 23% and 25% increase in FEV1 from baseline with one and two puffs, respectively (P less than .001). The differences between one and two actuations were, in general, not significant. No significant differences were observed between individuals who waited one versus five minutes between inhalations. We conclude that IM aerosol results in significant improvement compared with placebo for two hours. Differences between one and two inhalations and the interval between two inhalations did not, in general, lead to enhanced effectiveness of this drug in the group of asthmatics studied.

Adolescent↗

PubMed1986

Intratumoral Bacillus Calmette-Guérin immunotherapy prior to surgery for carcinoma of the lung: results of a prospective randomized trial.

A prospective randomized trial of preoperative intratumoral therapy with Bacillus Calmette-Guérin (BCG) was conducted in non-small cell lung cancer patients. Eighty-eight patients (48 BCG-treated and 40 control subjects) were entered into the study; three control subjects were removed from data analysis because histology revealed pathology other than non-small cell lung cancer. There were no differences between BCG-treated and control patients in sex, age, cigarettes smoked per day, pack-years of cigarette smoking, white blood cell count, or number of peripheral blood lymphocytes. Toxicity of BCG was limited to transient malaise and fever (average peak temperature, 38.7 degrees C). There was no significant difference in outcome (recurrence or survival) between BCG-treated and control groups with Stage I or Stage III tumors; there were too few Stage II tumors for separate statistical analysis. Outcome was not affected within or between the two treatment groups by tuberculin skin test status. Combining both treatment groups, Stage III patients had a worse outcome than did Stage I-II patients, non-squamous cell tumor patients (large cell and adenocarcinoma) had worse outcomes than did squamous cell tumor patients, and men had a worse outcome than women. We conclude that, although preoperative intratumoral BCG therapy is safe, it does not lengthen disease-free interval or prolong survival in patients with non-small cell lung cancer.

Bacterial Vaccines↗

PubMed1985

Respiratory symptoms associated with sulfur dioxide exposure.

Exposures to sulfur dioxide (SO2) have been associated with progressive, dose-dependent bronchoconstriction in sensitive individuals. The clinical significance of such changes remains poorly characterized. We studied subjective responses following exposure to low level concentrations of SO2 (less than 1 ppm) in a group of 10 healthy and 10 asthmatic subjects. The number and severity of complaints associated with SO2 increased with concentrations in both healthy and asthmatic subjects. Asthmatics indicated progressive lower respiratory complaints, such as wheezing, chest tightness, dyspnea and cough with increasing levels of SO2 while healthy subjects complained more frequently of upper airway complaints such as taste and odor with increasing levels of SO2. Exercise increased the frequency of lower airway symptoms in asthmatics but led to no increases in symptoms in healthy subjects.

Adult↗

PubMed1985

Estrogen replacement therapy and fibrocystic breast disease in postmenopausal women.

The association between estrogen replacement therapy and fibrocystic breast disease was assessed in a hospital-based case-control study undertaken in Connecticut from 1979 to 1981. The cases were 143 postmenopausal women with biopsy-confirmed fibrocystic breast disease, and the controls were 355 postmenopausal women with other surgical conditions. Use of estrogen replacement therapy was positively associated with fibrocystic breast disease; the odds of disease increased with duration of use, reaching an approximately fivefold excess odds for those who had taken menopausal estrogens for 10 or more years. There was no evidence that the positive association between estrogen replacement therapy and the occurrence of fibrocystic breast disease could be explained by differential medical care utilization or other possible risk factors of biopsied fibrocystic breast disease.

Adult↗