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Biomedical subjects

B Newman

Publications and source records attributed to B Newman.

At least 199 records · Page 11Linked to original sources
PubMed1988

Are heavy smokers different from light smokers? A comparison after 48 hours without cigarettes.

Correlates of heavy smoking (greater than or equal to 25 cigarettes per day) were examined in a group of 380 smokers participating in a minimal-contact smoking relapse prevention trial. The results indicate that heavy smokers are more dependent on cigarettes. Compared with smokers consuming 15 or fewer cigarettes per day, heavy smokers reported greater difficulty quitting, were more troubled by withdrawal symptoms, experienced stronger urges and cravings, and had higher scores on a modified version of the Fagerstrom tolerance questionnaire. Heavy smokers weighed more and were more obese as measured by body mass index. Eighty percent of heavy smokers were classified correctly using discriminant function analysis with two dependence-related measures entering as the most important discriminator variables. Logistic regression analyses yielded similar results. The findings underscore the importance of addressing potential physical dependence factors when developing smoking-cessation treatments for heavy smokers.

Adult↗
PubMed1988

Packaging of transducing DNA by bacteriophage P1.

P1 transduces bacterial chromosomal markers with widely differing frequencies. We use quantitative Southern hybridisations here to show that, despite this, most markers are packaged at similar levels. Exceptions are a group of markers near 2 min and another at 90 min which seem to be packaged at levels two- to threefold higher. We thus conclude that certain marker frequency variations in transduction can be explained by differences in packaging level, but that most cannot. The limited range in packaging levels suggests that P1 can initiate the packaging of chromosomal DNA from many sites. This idea is supported by our failure to find any chromosomal sequences with homology to the phage pac site and by the occurrence of hybridising bands which seem to suggest sequential packaging from a large number of specific sites. We eliminate the possibility that chromosomal DNA packaging is the result of endonucleolytic cutting by the P1 res enzyme.

Autoradiography↗
PubMed1988

Coexistent transient pulmonary edema and pericardial effusion.

Eight (23%) of 35 children with acute pericardial effusions due to infection or juvenile rheumatoid arthritis (JRA) had associated transient pulmonary edema demonstrated on plain chest radiographs. The presence or absence of radiographic pulmonary edema correlated well with clinical and hemodynamic parameters in patients with JRA but not in those with infectious pericarditis. There was no definite relationship between radiographic edema and amount of pericardial fluid as estimated echocardiographically or removed at pericardiocentesis. Rapidity of pericardial fluid accumulation could not be assessed in this study. Children of young age with underlying JRA were the most likely subjects to have radiographic pulmonary edema in conjunction with an acute pericardial effusion.

Adolescent↗
PubMed1988

Appendiceal perforation, pneumoperitoneum, and Hirschsprung's disease.

In this report, we describe an infant with appendiceal perforation due to total colonic Hirschsprung's disease, to emphasize this rare but important presentation of Hirschsprung's disease. Based on our own experience and a survey of similar cases, we suggest that an underlying etiology, namely long-segment Hirschsprung's disease, should be suspected in infants with a perforated appendix, especially when a radiographic pneumoperitoneum is present. Prompt diagnosis and appropriate therapy is essential in this situation to prevent morbidity and mortality.

Appendicitis↗
PubMed1988

Neonatal abdominal calcification: is it always meconium peritonitis?

Intraluminal meconium calcifications are a rare cause of neonatal abdominal calcifications and can easily be misinterpreted as meconium peritonitis. We report three patients with anorectal anomalies, rectourethral fistula, and intraluminal calcified meconium. Intestinal stasis and mixing of urine and meconium may be predisposing factors for the calcification of meconium. Intraluminal calcifications appear as discrete punctate flecks within the distribution of the bowel, in contrast to meconium peritonitis, where the calcifications are linear and plaque-like, occurring anywhere in the abdominal cavity and scrotum. Careful differentiation of abdominal calcifications will allow more appropriate planning of the need and timing of surgery and can suggest the possibility of other anomalies that may not be suspected initially.

Abdomen↗
PubMed1988

Inheritance of human breast cancer: evidence for autosomal dominant transmission in high-risk families.

Segregation analysis of breast cancer in families can provide the logical basis and the specific genetic models for mapping and identifying genes responsible for human breast cancer. Patterns of breast cancer occurrence in families were investigated by complex segregation analysis. In a sample of 1579 nuclear families ascertained through a population-based series of probands, an autosomal dominant model with a highly penetrant susceptibility allele fully explained disease clustering. From the maximum-likelihood Mendelian model, the frequency of the susceptibility allele was 0.0006 in the general population, and lifetime risk of breast cancer was 0.82 among susceptible women and 0.08 among women without the susceptibility allele. Inherited susceptibility affected only 4% of families in the sample: multiple cases of this relatively common disease occurred in other families by chance. The same genetic models, with higher gene frequency, explained disease clustering in an extended kindred at high risk of breast cancer. Evidence for a highly penetrant, autosomal dominant susceptibility allele for breast cancer in a high-risk family and the general population suggests that high-risk families can serve as models for understanding breast cancer in the population as a whole.

Adult↗
PubMed1988

Maternal inspired oxygen concentration and neonatal status for caesarean section under general anaesthesia. Comparison of effects of 33% or 50% oxygen in nitrous oxide.

The relationship between maternal FIO2 and umbilical venous PO2, PCO2, pH and neonatal Apgar and TSR (time to sustained respiration) scores was studied in 35 patients undergoing Caesarean section under general anaesthesia. Patients were allocated randomly to breathe an FIO2 of either 0.5 or 0.33. Umbilical venous blood was collected at the time of delivery, and TSR and 1- and 5-min Apgar scores recorded. Mean values for umbilical venous blood were: PO2 3.9 kPa and 3.7 kPa; PCO2 6.2 kPa and 6.2 kPa; pH 7.30 and 7.31 (50% and 33% groups, respectively (P greater than 0.05]. No differences were found between groups for 1- or 5-min Apgar scores or TSR values. It is concluded that no difference in fetal outcome or acid-base status can be detected when maternal FIO2 is decreased from 0.5 to 0.33, and that the use of 33% oxygen in 66% nitrous oxide appears to be safe for neonates who have not suffered fetal distress before delivery.

Anesthesia, General↗
PubMed1988

Occult fractures in preschool children.

Five hundred consecutive radiographic examinations of acutely limping infants and toddlers were analyzed retrospectively. One hundred of the 500 (20%) had a fracture as the underlying etiology. Although the most common sites of involvement were the tibia/fibula (56 cases) and femur (30 cases), fractures in the pelvis and feet, notably the metatarsals (11 cases), also were seen. We therefore recommend obtaining radiographs of the pelvis and both lower extremities including the feet, when occult trauma is suspected and the exact area of injury cannot be pinpointed clinically.

Child, Preschool↗
PubMed1988

Inheritance of low-density lipoprotein subclass patterns: results of complex segregation analysis.

Heterogeneity in the size of low-density lipoprotein (LDL) particles was used to identify two distinct patterns based on gradient gel electrophoresis analysis. These two phenotypes, LDL subclass pattern A and pattern B, were characterized by a predominance of large, buoyant LDL particles and small, dense LDL particles, respectively. The inheritance of these LDL subclass patterns was investigated in a sample of 61 healthy families including 301 individuals. LDL subclass pattern B was present in 31% of the subjects, with the prevalence varying by gender, age, and (in women) menopausal status. Complex segregation analysis suggested a major locus controlling LDL subclass patterns. The model providing the best fit to the data included a dominant mode of inheritance with a frequency of .25 for the allele determining LDL subclass pattern B and reduced penetrance for men under age 20 and for premenopausal women. Thus, the allele for the LDL subclass pattern characterized by a predominance of small, dense LDL particles appears to be very common in the population, although not usually expressed until adulthood in men and until after menopause in women. The presence of a major gene controlling LDL subclass could explain much of the familial aggregation of lipid and apolipoprotein levels and may be involved in increased risk of coronary heart disease.

Adolescent↗
PubMed1988

[Politico-administrative distribution of nutritional status according to a height census of 1st grade school children in Panama].

Height is the anthropometric measurement that best summarizes the effects of socioeconomic factors on the health and nutritional status of a given community. For the purpose of identifying the lowest disaggregation level, the political-administrative areas with the highest malnutrition prevalences, a height census that included 58,000 children who attended the 3,000 schools of the country was carried out. The Republic of Panama is politically-administratively divided into 9 provinces, 65 districts, one Indian community and 505 "corregimientos." The results obtained showed marked differences in height retardation among provinces, among districts and among "corregimientos." In the latter, retardation in first grade children varies from 0 to 95%. Important differences were also observed within a same district among "corregimientos", as is the case with the District of Natá, which vary from 4 to 40%. The height census permitted the identification and quantification of nutritional damage in 28 districts and 204 priority "corregimientos", where it is expected, resources from the public sector will be assigned in order to substantially reduce the prevailing poverty, as well as the food and nutrition problems.

Body Height↗
PubMed1988

Abnormal pulmonary aeration in infants and children.

There are many intrinsic and extrinsic, and congenital or acquired lesions that cause aeration disturbances in infants and children. The radiographic diagnosis of these entities and the pathophysiologic mechanisms by which they produce overinflation or underinflation are discussed. Longstanding airway compression may have serious effects on the developing lung and its vascular supply.

Airway Obstruction↗
PubMed1988

Radiologic evaluation of the diaphragm.

Recent technical advancements allow us to better evaluate the diaphragm and juxtadiaphragmatic lesions. Plain radiographs demonstrate morphology of the diaphragm in most cases. Function of the diaphragm can easily be evaluated by ultrasonography and fluoroscopy. Ultrasonography can be performed at bedside and should be used before fluoroscopy in infants and children. Ultrasonography can also demonstrate congenital anomalies of the diaphragm in utero. CT clearly discloses the underlying pathology and the extent of most juxtadiaphragmatic lesions. The newest modality, MRI, is quite promising and may become the procedure of choice for evaluation of diaphragmatic as well as juxtadiaphragmatic lesions in the very near future.

Diaphragm↗
PubMed1988

Pulmonary pseudofibrosis and pseudomass lesions.

Abnormal size and/or number of the pulmonary and bronchial vessels and lymphatics may mimic pulmonary parenchymal lesions (pseudofibrosis). Abnormalities of the central pulmonary artery, pulmonary vein, thoracic aorta, and brachiocephalic branches may mimic intrathoracic mass lesions (pseudomass lesions). Radiologists should interpret these radiographic findings in the light of other accompanying radiographic findings and the clinical presentation.

Bronchial Arteries↗
PubMed1988

Disturbances of bone growth and development.

"What is growth anyway? Can one talk about positive growth in childhood, neutral growth in maturity, and negative growth in old age?" Our goal is to help promote normal positive growth in infants and children. To achieve this, we must be cognizant of the morphologic changes of both normal and abnormal bone formation as they are reflected in the radiographic image of the skeleton. The knowledge of the various causes and the pathophysiologic mechanisms of the disturbances of bone growth and development allows us to recognize the early radiographic manifestations. Endocrine and metabolic disorders affect the whole skeleton, but the early changes are best seen in the distal ends of the femurs, where growth rate is most rapid. In skeletal infections and in some vascular injuries two-or three-phase bone scintigraphy supercedes radiography early in the course of the disease. MRI has proved to be very helpful in the early detection of avascular bone necrosis, osteomyelitis, and tumor. Some benign bone tumors and many bone dysplasias have distinct and diagnostic radiographic findings that may preclude further studies. In constitutional diseases of bone, including chromosomal aberrations, skeletal surveys of the patient and all family members together with biochemical and cytogenetic studies are essential for both diagnosis and genetic counseling. Our role is to perform the least invasive and most informative diagnostic imaging modalities that corroborate the biochemical and histologic findings to establish the definitive diagnosis. Unrecognized, misdiagnosed, or improperly treated disturbance of bone growth can result in permanent deformity usually associated with disability.

Bone Diseases, Developmental↗
PubMed1987

Nonutility of cineurograms in children with congenital heart disease.

Cineurography is often performed after cineangiocardiography to look for occult congenital urinary tract disease. The accuracy of cineurography was investigated in 171 patients by comparing cineurograms with renal sonograms. One hundred fifteen cineurograms (67%) showed both kidneys well enough to allow assessment of renal structure and function and the results were confirmed in 112 by ultrasonography; 3 cineurograms yielded false-positive results. Limited or no information was obtained from cineurograms of 56 patients (33%) because of nonvisualization or poor visualization of 1 or both kidneys. Of the 11 patients (6%) with urinary tract disease, only 3 were correctly assessed by cineurography. Ultrasonography discovered all 11 renal abnormalities and produced only 1 false-positive result. These data indicate that cineurography is a poor screening test and should be abandoned. When uroradiologic screening is necessary for high-risk patients, sonography is recommended.

Adolescent↗
PubMed1987

Intravesical chemotherapy: combination with Tween 80 increases cytotoxicity in vitro.

Tween 80 was shown to enhance significantly the cytotoxic activities of the four drugs (adriamycin, epodyl, mitomycin-c, thiotepa) most frequently administered intravesically to treat superficial bladder cancer. The colony forming ability of a human bladder cancer cell line, RT112, was measured following a 1 h exposure to each of the four drugs both alone and in combination with 0.1% and 0.3% Tween 80. Cell survival was not reduced by 0.1% Tween 80 alone. We conclude that the combination of Tween 80 with these drugs might increase the therapeutic index of intravesical chemotherapy.

Administration, Intravesical↗
PubMed1987

Concordance for type 2 (non-insulin-dependent) diabetes mellitus in male twins.

Concordance for Type 2 (non-insulin-dependent) diabetes was determined in 250 monozygotic and 264 dizygotic white male twin pairs who participated in the National Heart, Lung, and Blood Institute Twin Study. These twins were born between 1917 and 1927 and were identified from military records without regard to disease status. We examined surviving members of the cohort twice--at mean ages of 47 and 57 years--and obtained 1-h post-load glucose tests and medication histories. Diagnostic criteria for Type 2 diabetes included a glucose value greater than or equal to 13.9 mmol/l or current use of antidiabetic medication; possible Type 1 (insulin-dependent) diabetic twins were excluded. A strong genetic predisposition to Type 2 diabetes was suggested by 3 lines of evidence from the second examination: (1) 58% of monozygotic co-twins of diabetic twins were themselves diabetic compared with an expected prevalence of 10%; (2) only 1 of 15 originally disease-discordant, monozygotic twin pairs remained discordant for diabetes; and (3) 65% of non-diabetic monozygotic co-twins of diabetic twins had elevated glucose values. Because concordance for diabetes was less than 100% for twins aged 52-65 years and because twins varied in age at onset of disease, non-genetic factors may also influence diabetes development. Among the 19 monozygotic twins pairs discordant for diabetes, diabetic twins did not differ from their non-diabetic co-twins in obesity, diet, alcohol consumption, or education. However, compared with unrelated non-diabetic twins of the same ages, non-diabetic co-twins of diabetic twins gained more weight as adults (p less than 0.02) and had higher glucose levels (p less than 0.03).

Body Weight↗