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Biomedical subjects

J Berg

Publications and source records attributed to J Berg.

At least 73 records · Page 4Linked to original sources
PubMed1996

Permeability properties of the intact mammalian bladder epithelium.

Because the mammalian bladder must store urine of composition which differs markedly from that of plasma for prolonged periods, the bladder permeability barrier must maintain extremely low permeabilities to substances which normally cross membranes relatively rapidly, such as water, protons, and small nonelectrolytes like urea and ammonia. In the present studies, permeabilities of the apical membrane of dissected rabbit bladder epithelium to water, urea, ammonia, and protons were measured in Ussing chambers and averaged (in cm/s) for water, 5.15 +/- 0.43 x 10(-5); for urea, 4.51 +/- 0.67 x 10(-6); for ammonia, 5.14 +/- 0.62 x 10(-4); and for protons, 2.98 +/- 1.87 x 10(-3), respectively. These permeability values are exceptionally low and are expected to result in minimal to no leakage of these normally permeable substances across the epithelium. Water permeabilities in intact whole rabbit bladders were indistinguishable from those obtained in the dissected epithelial preparation. Moreover, addition of nystatin to the apical solution of dissected epithelia rapidly increased water permeability in conjunction with loss of epithelial resistance. These results confirm that the apical membrane of the bladder epithelial cells represents the bladder permeability barrier. In addition, they establish a model system that will permit examination of how membrane structure reduces permeability and how epithelial injury compromises barrier function.

Ammonia↗
PubMed1996

Quality of life in COPD patients using transtracheal oxygen.

Transtracheal oxygen offers patients with chronic obstructive pulmonary disease many benefits. A qualitative study was conducted to examine patients' perceptions of how the technology affects quality of life. This study has several implications for nurses working in hospital and home settings.

Activities of Daily Living↗
PubMed1995

Ultrasonography of the brain and vertebral canal in dogs and cats: 15 cases (1988-1993).

Medical records of 3 cats and 12 dogs with lesions of the brain (3 cats, 2 dogs) or vertebral canal (10 dogs) that underwent intraoperative ultrasonography were reviewed. Ultrasonography was performed after craniotomy, a ventral slot procedure, or laminectomy, using a real-time sector scanner with a 7.5- or 10-MHz transducer. In the 3 cats and 2 dogs with brain lesions, cerebral masses were hyperechoic, compared with normal brain, and were easily located. In the 2 dogs, ultrasonography was necessary to localize deep-seated cerebral lesions that could not be seen following craniotomy. In 7 dogs that underwent a ventral slot procedure because of prolapse of an intervertebral disk, ultrasonography was successfully used to assess completeness of disk removal. The remaining 3 dogs underwent dorsal laminectomy because intradural enlargement of the spinal cord (1 dog) or an intradural mass (2 dogs) could be seen myelographically. In the 2 dogs with intradural masses, intraoperative ultrasonography helped to delineate the extent of the tumor. In the third dog, spinal cord swelling was seen ultrasonographically; the histologic diagnosis was spinal cord edema.

Animals↗
PubMed1995

Results of surgery and doxorubicin chemotherapy in dogs with osteosarcoma.

Thirty-five dogs with appendicular osteosarcoma were treated with 5 doses of doxorubicin (30 mg/m2 of body surface, i.v., every 2 weeks). Surgical excision of the primary tumor was performed 13 days after the second (n = 18) or third (n = 17) treatment, and the subsequent doxorubicin treatment was given the day following surgery. Resected tumors were evaluated histologically to determine response to preoperative chemotherapy (ie, percentage of the tumor that was necrotic). Survival data for the 35 dogs were compared with survival data for a historical control group, consisting of 162 dogs with appendicular osteosarcoma treated by amputation alone. Administration of doxorubicin at 2 week intervals was well tolerated. Three dogs were alive and did not have evidence of disease at the time of reporting. Of the remaining 32 dogs, 3 died or were euthanatized because of cardiomyopathy presumably caused by doxorubicin; 1 died suddenly 116 weeks after initiation of treatment; and the remaining 28 were euthanatized because of problems documented to be related to distant metastases. Thirteen dogs (40.6%) were euthanatized because of pulmonary metastases, 10 dogs (31.3%) were euthanatized because of bone metastases, and 5 dogs (15.6%) were euthanatized because of metastases in other sites. The proportion of dogs euthanatized because of bone metastases was significantly (P < 0.001) higher for the study group than for the control group. Median survival time for the 35 dogs that received doxorubicin was estimated to be 52.3 weeks, and 1- and 2-year survival rates were estimated to be 50.5 and 9.7%, respectively. Survival time was significantly (P < 0.0001) longer for these dogs than for control dogs.(ABSTRACT TRUNCATED AT 250 WORDS)

Amputation, Surgical↗
PubMed1995

Is there a hemispheric side preference of cardiac valvular emboli?

Microaggregates arising from prosthetic cardiac valves offer the opportunity to examine the distribution of valvular emboli in the human cerebral circulation. Forty-four patients with different kinds of prosthetic valves underwent bilateral transcranial Doppler monitoring for 1 h to detect high intensity Doppler signals representing microemboli. Comparing the total number of embolic signals in both middle cerebral arteries (N = 1066), a side preference was not statistically evident. However, clear side preferences were obvious in some individuals. The lack of statistical evidence for hemispherical preferences of cardiac microembolism in general does not exclude selective streaming in individuals, explaining the clinical observation of lodging preferences of recurrent cardiac embolism. A cardiac source of microembolism may mimic disease activity of extracranial carotid artery stenosis and bias the localization of embolic source.

Adult↗
PubMed1995

Opitz BBBG syndrome: new family with late-onset, serious complication.

The Opitz BBBG syndrome is characterized by hypertelorism and (in male patients) hypospadias, in addition to a number of midline abnormalities: posterior laryngeal cleft, stridor, swallowing dysfunction, cardiac defects, imperforate anus, and urinary tract and CNS anomalies. Inheritance is autosomal dominant (McKusick number *145410) with partial male sex limitation in most pedigrees. We report a Dutch family with Opitz BBBG syndrome in which the proband developed late-onset symptoms of a structural laryngeal abnormality.

Abnormalities, Multiple↗
PubMed1995

CAVIAR: a tool to improve serial analysis of the 12-lead electrocardiogram.

An important part of an electrocardiogram (ECG) interpretation is the comparison between the present ECG and earlier recordings. The purpose of the present study was to evaluate a combination of two computer-based methods, synthesized vectorcardiogram (VCG) and CAVIAR, in this comparison. The methods were applied to a group of 38 normal subjects and to a group of 36 patients treated with anthracyclines. A fraction of these patients are likely to develop cardiac injury during or after the treatment, since anthracyclines are known to cause heart failure and cardiomyopathy. Two ECGs were recorded on each patient, one before and one after the treatment. On each normal subject, two ECGs were recorded with an interval of 8-9 years. A synthesized VCG was calculated from each ECG and the two synthesized VCGs from each subject were analysed with the CAVIAR method. The CAVIAR analysis is a quantitative method and normal limits for four measurements were established using the normal group. Values above these limits were more frequent in the patient group than in the normal group. The conventional ECGs were also analysed visually by an experience ECG interpreter without knowledge of the result of the CAVIAR analysis. No significant serial changes were found in 10 of the patients with high CAVIAR values. Changes in the ECGs were found in two patients with normal CAVIAR values. In summary, synthesized VCG and CAVIAR could be used to highlight small serial changes that are difficult to find in a visual analysis of ECGs.

Adult↗
PubMed1995

Variability of Doppler microembolic signal counts in patients with prosthetic cardiac valves.

BACKGROUND AND PURPOSE: The purpose of this study was the evaluation of intraobserver, interobserver, and intrasubject variability in the Doppler detection of microembolic signals in patients with mechanical prosthetic valves. Simultaneously, the feasibility of automated embolus detection by means of a neuronal network was investigated. METHODS: From 25 patients with mechanical prosthetic heart valves, single transcranial Doppler monitoring sessions of 30 minutes' duration were recorded on videotape, randomized, and subsequently analyzed by eight independent trained observers from three centers. Three observers evaluated these tapes on three separate occasions, blinded to their previous results. An additional 48 patients with prosthetic heart valves were repetitively monitored with transcranial Doppler ultrasonography for 30 minutes three times within 1 year to examine the long-term variability in the occurrence of microembolic signals. Finally, in an effort to assess the short-term intrasubject variability, 20 patients were examined for 90 minutes, and the results of the three 30-minute periods were compared. The interobserver, intraobserver, and intrasubject (both short- and long-term) variability was evaluated. RESULTS: No significant differences in microembolic signal counts were found among the different observers, between the human observers and the neuronal network, or among the three separate evaluations of stored data by the same observer. The same was true for repeat examinations of the same patient (P > .05, Student's two-paired t test and Friedman's test). CONCLUSIONS: The detection of microembolic signals in patients with prosthetic cardiac valves is a reproducible technique. The reliable performance of the neuronal network argues for a broader use of this device. The intrasubject stability of the microembolic rate over 1 year supports the concept that the underlying emboligenic process is associated with intrinsic mechanical properties of the valve implant and not due to a thromboembolic process in the heart.

Cerebral Arteries↗
PubMed1994

Chylous ascites in cats: nine cases (1978-1993).

Medical records of 9 cats with chylous ascites that underwent exploratory celiotomy were reviewed. In 7 cats, chylous ascites was associated with intra-abdominal neoplasia: 4 cats had an unresectable tumor (hemangiosarcoma, 3 cats; paraganglioma, 1 cat) within the mesenteric root; 2 had malignant lymphoma of the small intestine and mesenteric lymph nodes; and 1 had lymphangiosarcoma of the abdominal wall. In 2 cats, chylous ascites was associated with nonneoplastic diseases: 1 cat had severe biliary cirrhosis and an extrahepatic portosystemic shunt; the other had steatitis caused by vitamin E deficiency. Three cats were euthanatized or died at the time of surgery, and 5 cats were euthanatized within 3 months of surgery. One cat with malignant lymphoma responded well to chemotherapy and lived for 14 months after surgery.

Animals↗
PubMed1994

Evaluation of butorphanol and cyproheptadine for prevention of cisplatin-induced vomiting in dogs.

Cisplatin was administered at a dosage of 50 mg/m2 of body surface to 69 dogs with various neoplasms. Dogs were randomly assigned to receive antiemetics according to 1 of the following 5 protocols: group 1, no antiemetic (control, n = 45 treatments); group 2, 0.4 mg of butorphanol/kg of body weight (n = 52 treatments); group 3, 0.2 mg of butorphanol/kg (n = 19 treatments); group 4, 2 mg of cyproheptadine/kg (n = 48 treatments); and group 5, 1 mg of cyproheptadine/kg (n = 10 treatments). Randomization was performed for each dog prior to each treatment. Butorphanol was administered IM immediately after completion of cisplatin infusion. Cyproheptadine was given orally 12 to 14 hours before and again immediately before cisplatin administration. The proportion of dogs that vomited in group 1 was 40 of 45 (89%). Butorphanol at a dosage of 0.4 mg/kg proved highly effective in preventing cisplatin-induced vomiting, reducing the proportion of dogs that vomited (10/52, 19%) compared with the control group.

Animals↗
PubMed1994

Surgical treatment of thymoma in cats: 12 cases (1987-1992).

Twelve cats with thymoma were treated by surgical excision of the tumor alone. None of the cats received radiotherapy or chemotherapy. Two cats died or were euthanatized during the immediate postoperative period: 1 because of postsurgical hemorrhage, and the other because of an associated fungal pleuritis. None of the remaining 10 cats developed evidence of local tumor recurrence or metastases. Six of the cats were alive after follow-up periods ranging from 6 to 36 months (mean, 21 months; median, 21 months). Three cats were euthanatized 18 months, 32 months, and 45 months following surgery for unrelated problems, and 1 cat died as a result of trauma sustained 62 months postoperatively. Myasthenia gravis developed postoperatively in 2 of the cats.

Animals↗
PubMed1994

Homozygous Tangier disease and cardiovascular disease.

Decreased levels of plasma high density lipoprotein (HDL) cholesterol have been associated with premature cardiovascular disease (CVD). Tangier disease is an autosomal co-dominant disorder in which homozygotes have a marked deficiency of HDL cholesterol and apolipoprotein (apo) A-I levels (both < 10 mg/dl), decreased low density lipoprotein (LDL) cholesterol levels (about 40% of normal), and mild hypertriglyceridemia. Homozygotes develop cholesterol ester deposition in tonsils (orange tonsils), liver, spleen, gastrointestinal tract, lymph nodes, bone marrow, and Schwann cells. Our purpose was to assess the prevalence of CVD in Tangier disease. We reviewed published clinical information on 51 cases of homozygous Tangier disease, report 3 new cases and provide autopsy information on 3 cases. Mean (+/- S.D.) lipid values of all cases were as follows: total cholesterol 68 +/- 30 mg/dl (32% of normal), triglycerides 201 +/- 118 mg/dl (162% of normal), HDL cholesterol 3 +/- 3 mg/dl (6% of normal) and LDL cholesterol 50 +/- 38 mg/dl (37% of normal). The most common clinical finding in these subjects (n = 54) was peripheral neuropathy which was observed in 54% of cases versus < 1% of control subjects (n = 3130). CVD was observed in 20% of Tangier patients versus 5% of controls (P < 0.05), and in those that were between 35 and 65 years of age, 44% (11 of 25) had evidence of CVD (either angina, myocardial infarction or stroke) versus 6.5% in 1533 male controls and 3.2% in 1597 female controls in this age group (P < 0.01). In 9 patients who died, 2 died prior to age 20 of probable infectious diseases, 3 of documented coronary heart disease at ages 48, 64, and 72, 2 of stroke at ages 56 and 69, one of valvular heart disease, and 1 of cancer. In three autopsy cases, significant diffuse atherosclerosis was observed in one at age 64, moderate atherosclerosis and cerebral infarction in another at age 56, but no atherosclerosis was noted in the third case who died of lymphoma at age 62. In one patient with established coronary heart disease, none of the lipid lowering agents used (niacin, gemfibrozil, estrogen or lovastatin) raised HDL cholesterol levels above 5 mg/dl. However, these agents did have significant effects on lowering triglyceride and LDL cholesterol levels. Our data indicate that there may be heterogeneity in these patients with regard to CVD risk, that peripheral neuropathy is a major problem in many patients, and that CVD is a significant clinical problem in middle aged and elderly Tangier homozygotes.(ABSTRACT TRUNCATED AT 400 WORDS)

Adult↗
PubMed1994

Characterization of a psychrotrophic Clostridium causing spoilage in vacuum-packed cooked pork: description of Clostridium algidicarnis sp. nov.

A Clostridium species causing spoilage of vacuum-packed refrigerated pork was isolated and characterized. The unknown organism differed phenotypically from other clostridial species usually associated with spoilage. Phylogenetic analyses based on 16S rRNA gene sequencing demonstrated that the psychrotroph represents a distinct line of descent within the genus Clostridium. It is proposed that the organism be classified as a new species of the genus Clostridium, Clostridium algidicarnis.

Animals↗
PubMed1994

Third- and fourth-generation implantable cardioverter defibrillators: current status and future development.

Implantable cardioverter defibrillator (ICD) therapy has become the mainstay of therapy for patients with a history of sudden cardiac death or life-threatening ventricular arrhythmias. The current generation of ICDs used for secondary prevention combines features for tachycardia reversion with demand ventricular pacing, antitachycardia pacing, programmable shock therapy, and tachycardia events memory. Although demand pacing and defibrillation is indicated for primary prevention usage of ICDs, the application of antitachycardia pacing modes is more controversial. High energy cardioversion and defibrillation shocks remaining the mainstay of sudden death prevention will be redefined as more effective defibrillation shock modes and lead systems are developed. Fourth-generation ICD systems accomplished a significant reduction of device size and almost universal success using an endocardial lead configuration and pectoral implant. A variety of new directions of ICD therapy in clinical practice such as primary prevention applications and the adjunctive role of antiarrhythmic drug therapy are currently being examined in clinical trials. The concepts underlying initiation of tachyarrhythmias are being studied to develop new approaches to tachycardia prevention. These include rate support, subthreshold stimulation, and multiple site pacing. The current developments of ICD therapy promise continued growth of this technology.

Anti-Arrhythmia Agents↗