Search PubMed⌕ Search

Biomedical subjects

J Berg

Publications and source records attributed to J Berg.

At least 109 records · Page 6Linked to original sources
PubMed1990

Preoperative measurement of canine primary bone tumors, using radiography and bone scintigraphy.

Specimens of 20 canine primary bone tumors (18 osteosarcoma, 2 fibrosarcoma) were examined to compare the maximal axial length of gross tumor with the length of the lesion seen on preoperative radiographs and 99mTc methylene diphosphonate bone scintigraphic images. Radiographs defined the length of the tumor to within +/- 10% of the gross measurement for 6 (30%), underestimated it for 12 (60%), and overestimated it for 2 (10%) specimens. Bone scintigraphy defined tumor length within +/- 10% for 8 (40%), underestimated it for 1 (5%), and overestimated it for the remaining 11 (55%) specimens. Use of radiographic evaluation alone could result in underestimation of the diaphyseal extent of a primary bone tumor, with risk of incomplete resection. Bone scan images tend to overestimate tumor length and, therefore, may provide safer resection guidelines.

Animals↗
PubMed1990

Bone scintigraphy in the initial evaluation of dogs with primary bone tumors.

Bone scintigraphy was performed as part of an initial diagnostic evaluation of 70 dogs admitted with primary bone tumors during a 2-year period. Tumors involved major long bones of the appendicular skeleton and included 62 osteosarcomas, 6 fibrosarcomas, and 2 chondrosarcomas. All dogs were free of radiographically detectable pulmonary metastases. Bone scintigraphy was not of value in distinguishing among various types of primary tumors. One dog with an ulnar chondrosarcoma had a scintigraphically detectable occult osseous metastasis or synchronous primary tumor, and 1 dog with osteosarcoma had a scintigraphically detectable lymph node metastasis. Pulmonary metastases were not detected scintigraphically. Of the 70 dogs, 44.3% had areas of increased isotope uptake associated with nonneoplastic disease processes.

Animals↗
PubMed1990

Liquid chromatographic determination of 2',3'-dideoxyguanosine in human plasma.

A rapid assay for 2',3'-dideoxyguanosine (ddG) in human plasma has been developed. The ddG was first extracted from human plasma using solid phase extraction. The extract containing ddG was then assayed with liquid chromatography using an ODS column and a mobile phase of 9% methanol in pH 6.8 phosphate buffer. The overall method had good accuracy (within 2%), linearity (r = 0.9998), sensitivity (LOD = 1.8 ng, S/N = 3) and recovery (greater than 99% for 5-50 micrograms ddG per ml plasma).

Chromatography, Liquid↗
PubMed1990

Immunoglobulin lambda gene rearrangement can precede kappa gene rearrangement.

Immunoglobulin genes are generated during differentiation of B lymphocytes by joining gene segments. A mouse pre-B cell contains a functional immunoglobulin heavy-chain gene, but no light-chain gene. Although there is only one heavy-chain locus, there are two light-chain loci: kappa and lambda. It has been reported that kappa loci in the germ-line configuration are never (in man) or very rarely (in the mouse) present in cells with functionally rearranged lambda-chain genes. Two explanations have been proposed to explain this: (a) the ordered rearrangement theory, which postulates that light-chain gene rearrangement in the pre-B cell is first attempted at the kappa locus, and that only upon failure to produce a functional kappa chain is there an attempt to rearrange the lambda locus; and (b) the stochastic theory, which postulates that rearrangement at the lambda locus proceeds at a rate that is intrinsically much slower than that at the kappa locus. We show here that lambda-chain genes are generated whether or not the kappa locus has lost its germ-line arrangement, a result that is compatible only with the stochastic theory.

Alleles↗
PubMed1989

Daily living with COPD. Self-help skills to improve functional ability.

Although patients with chronic obstructive pulmonary disease (COPD) experience many problems as a result of their disease, they can use numerous strategies to maximize functional ability and maintain health. Patients with COPD should be encouraged to learn more about their disease and use commonsense approaches to management. Referral to a pulmonary rehabilitation program that offers comprehensive assessment, individualized treatment, and access to support groups is also valuable. Rehabilitation programs often result in an improved capability for daily activities and a better quality of life.

Activities of Daily Living↗
PubMed1989

Translation affects immunoglobulin mRNA stability.

When termination codons were introduced into exons of the gene for Ig mu chain, steady-state levels of mu mRNA were reduced, both at the pre-B cell stage and at the plasma cell stage. A termination codon in the variable region gene segment and a termination codon in the second exon of the constant region gene segment had effects of similar magnitude. When the termination codon was deleted, the original level of mRNA was restored. The rate of mu gene transcription was the same whether or not a termination codon was present. Therefore, the termination codons must reduce the amount of the mRNA by reducing its stability. Since the introduced termination codons prematurely terminate translation and, in so doing, change the ribosome load on the mRNA, we conclude that mu mRNA stability is conferred in part by ribosomal protection from enzymatic degradation. We propose that the differences in mu mRNA stability during B lymphocyte differentiation are due to different amounts of ribosomes available for translation.

B-Lymphocytes↗
PubMed1989

Arterial embolization in patients with renal carcinoma.

The literature concerning embolization of the renal artery in patients with renal cell carcinoma is reviewed. Based on this review it is concluded that the method is useful in this patient group as it will facilitate the surgical procedure if nephrectomy is performed afterwards. Used as a palliative method, embolization reduces haematuria. It was not possible to draw conclusions concerning survival rates or eventual immuno-stimulating effects of embolization.

Carcinoma, Renal Cell↗
PubMed1989

Subcapsular hematoma of the liver during pregnancy.

We have reported a case of subcapsular hematoma of the liver, diagnosed and observed by ultrasonography, in association with the HELLP syndrome. The patient's condition improved with conservative management, but the hematoma was clearly shown to last for more than 12 weeks, which shows the need for extended postpartum follow-up and appropriate patient consultation.

Adult↗
PubMed1989

Correction of nonuniform attenuation in cardiac SPECT imaging.

Correction for photon attenuation in cardiac SPECT imaging using a measured attenuation distribution with an iterative expectation maximization (EM) algorithm and an iterative Chang algorithm were compared with the conventional filtered backprojection and an iterative EM algorithm without attenuation correction. The attenuation distribution was determined from a transmission computed tomography study that was obtained using an external collimated sheet source. The attenuation of the emitting photons was modeled in the EM algorithm by an attenuated projector-backprojector that used the estimated attenuation distribution to calculate attenuation factors for each pixel along each projection and backprojection ray. Results from a heart-lung phantom study and a 201Tl patient study demonstrated that the iterative EM algorithm with attenuation correction provided improved image quality in terms of reduced streak artifacts and noise, and more accurate quantitative information in terms of improved radioactivity distribution uniformity where uniformity existed, and better anatomic object definition.

Algorithms↗
PubMed1989

The adolescent with myelomeningocele: a review of parent experiences and expectations.

Until recently, persons born with spina bifida rarely lived to adulthood, and the severity of their physical and medical problems has been the source of litigation (e.g., Baby Jane Doe). This study questioned the parents of 39 adolescent survivors about their child's past medical history and psychosocial needs. While all of these adolescents had extensive histories of neurological and/or urological surgeries, most were mainstreamed into regular classroom settings. Three-fourths of the parents rated their adolescent as happy and outgoing. Less than 10% noted a predominant angry or depressed mood. The majority of adolescents had three or more close friends. About 10% stated that their child had problems with alcohol or drugs. Parents evaluated the support they had received on the medical and physical aspect of their child's illness as greater than that on psychosocial issues (e.g., sexuality, vocational needs). The desire for more assistance was expressed in these psychosocial areas (45% for sexuality and 68% for vocational needs) and in teenage issues (57%).

Activities of Daily Living↗
PubMed1988

Anorexia tardive: a diagnosis of exclusion?

An elderly female patient is described in whom rapid severe weight loss appeared initially to be of psychogenic origin and self-induced. A diagnosis of late-onset anorexia nervosa or anorexia tardive was made when early investigations revealed no abnormality apart from changes that were consistent with malnutrition, and when typical behavioural and psychological factors together with putative psychodynamic issues were revealed. At first, nasogastric feeding was beneficial, but a stormy hospital course ensued. Further investigations revealed the presence of neoplastic disease which at post-mortem examination proved to be small-cell carcinoma of the lung.

Aged↗
PubMed1988

Epidural opioids as anaesthesia for extracorporeal shock wave lithotripsy in two patients with cardiac disease.

Two patients with cardiac disease underwent Extracorporeal Shock Wave Lithotripsy (ESWL) in the Dornier HM3 machine. In order to minimize cardiovascular changes, epidural opioids (fentanyl 100 micrograms in 10 ml saline was used in one patient and meperidine 50 mg in 10 ml saline in the other patient) were used as an alternative to either general anaesthesia or epidural local anaesthesia. Both patients displayed haemodynamic stability, remained pain-free and experienced no complications. Epidural opioids proved a suitable form of anaesthesia for ESWL in these patients.

Analgesics, Opioid↗
PubMed1988

Evidence for a high attack rate and efficacy of erythromycin prophylaxis in a pertussis outbreak in a facility for the developmentally disabled.

During an outbreak of pertussis in residents and staff of a facility for the developmentally disabled, 149 persons had laboratory evidence of Bordetella pertussis infection; 130 (87%) reported respiratory illness. Infection rates (IR) in affected wards ranged from 6% to 91%. Most residents were adolescents and adults and had received a full course of diphtheria-tetanus toxoids-pertussis (DTP) vaccine; IRs increased with increasing time after the last DTP dose in fully vaccinated residents. The IR was lower in residents on wards where erythromycin treatment/prophylaxis was started two or fewer weeks after the onset of illness in the first case on the ward (IR, 16%), compared with four or more weeks after onset (IR, 75%; P less than 10(-6)). Respiratory symptoms were milder in ill residents treated within seven days of onset of illness. Although B. pertussis transmission was substantial, erythromycin treatment of patients and prophylaxis of exposed persons was effective in decreasing transmission and disease severity. Carbamazepine toxicity occurred in seven (19%) of 37 residents when carbamazepine was administered with erythromycin.

Adolescent↗
PubMed1988

Anaesthesia for extracorporeal shockwave lithotripsy at the Victorian Lithotripsy Service--the first 300 patients.

A prospective survey was undertaken of the anaesthesia for the first 300 patients at the Victorian Lithotripsy Service. The majority (71.7%) were not hospitalised on site, including four quadriplegics and two ASA grade IV patients. Two hundred and eighty-three (94.3%) patients received continuous lumbar epidural anaesthesia, sixteen (5.3%) received general anaesthesia and one received a spinal anaesthetic. Eighty-two patients (27.3%) underwent ancillary procedures at the time of extracorporeal shockwave lithotripsy. The most common intraoperative complications were hypotension (72 patients, 25.4%) and shivering (39 patients, 13.8%). Arrhythmias occurred in nine (3%) patients. There was a 90% patient follow-up rate and the most common postoperative complication was backache (101 patients, 37.4%). The problems of anaesthesia for extracorporeal shockwave lithotripsy are discussed. Epidural anaesthesia offers a number of advantages for this procedure and proved very suitable for the majority of patients.

Adolescent↗
PubMed1988

Determination of the optimum filter function for SPECT imaging.

An observer study was performed in order to evaluate several filters used in SPECT imaging. The filters were applied to the simulated projection data of a uniform activity density cylinder which contained a cold, spherical lesion, 2 cm in diameter. The data incorporated the effects of the detector and scatter response functions, photon attenuation, and noise. Reconstructed transaxial images were used in 2AFC and ROC observer studies testing lesion detectability. In the 2AFC experiment, the Hanning filter scored lowest and did not show a optimum cutoff frequency. The Butterworth filter performed better and showed a well-defined optimum cutoff frequency at 0.15 cycles/pixel. The Metz filter performed as well as the optimum Butterworth but did not show an optimum power factor. In the ROC study, a high power Metz filter demonstrated an ROC curve of lower Az index and different shape from a lower power Metz filter and the optimum Butterworth filter.

Filtration↗