Breast cancer and second primary ovarian cancer in dermatomyositis.

We report six female patients with breast cancer who developed dermatomyositis and compare our data with those from other reports. The development of dermatomyositis in two patients led to the discovery of a second primary ovarian carcinoma, whereas the development of dermatomyositis in another two patients led to the discovery of recurrent breast cancer. In three patients the diagnosis of dermatomyositis preceded the diagnosis of breast cancer, while the rest developed dermatomyositis after the diagnosis of breast cancer. A parallel clinical course of dermatomyositis and breast cancer was seen in only one patient. Coexisting dermatomyositis and breast cancer is a rare phenomenon, and dermatomyositis that develops during the course of breast cancer may indicate the occurrence of a second primary malignancy or recurrent breast cancer. The onset of dermatomyositis may precede, coincide with, or follow the diagnosis of breast cancer. The clinical course of dermatomyositis sometimes, but not always, parallels the course of breast cancer. There are no specific clinical or laboratory markers to distinguish patients with dermatomyositis who have malignancy from those without cancer.     

Vasopressin levels and pediatric head trauma

The syndrome of inappropriate secretion of antidiuretic hormone is associated with head trauma; however, there are no reports concerning vasopressin levels in pediatric patients with head trauma. Urine vasopressin in eight children (mean +/- SEM, age 7.5 +/- 1.6 years, range 1 to 15 years) was measured by radioimmunoassay during their hospitalization for head trauma. Urine vasopressin values for ten healthy children (mean age 5.4 +/- 1.3 years) and for eight children hospitalized for systemic antibiotic treatment of infections (age 5.9 +/- 1.8 years) also were obtained. Urine vasopressin, urine and serum sodium concentration and osmolality, urea nitrogen, creatinine, and fluid intake were measured within 24 hours of admission and daily for the following two days. For the first three days following head trauma, mean urine vasopressin levels in pediatric patients with head trauma were increased (P less than .05) compared with those of healthy children. Despite fluid restriction to 85% of maintenance level, 25% of patients with head trauma exhibited the clinical syndrome of inappropriate secretion of antidiuretic hormone (hyponatremia, increased urinary sodium, diminished serum osmolality, and urine osmolality greater than serum osmolality). Urine osmolality greater than 800 mosm/kg was associated with markedly increased urine vasopressin levels (200 to 1,650 pg/mL); children with this finding may be at particular risk for the syndrome of inappropriate secretion of anti-diuretic hormone without restrictive water intake.     

Pseudomonas cepacia: a new pathogen in patients with cystic fibrosis referred to a large centre in the United Kingdom.

Pseudomonas cepacia infection has become increasingly common among patients with cystic fibrosis in North America. In a large cystic fibrosis centre in the United Kingdom 11 cases have been identified during the last six years, with a maximum prevalence of 7% in 1988. Three patients have died, two of whom deteriorated rapidly shortly after acquisition of the organism despite intensive treatment with appropriate antibiotics. Analysis of possible causes of the increase in P cepacia infection suggested that neither patient to patient transmission nor the use of nebulised antibiotics was associated with an increased risk of infection.     

Ethnic differences in incidence of sudden infant death syndrome in Birmingham.

Among the 45,204 live births in Birmingham in the three calendar years 1981-3, there were 218 postneonatal deaths, giving a postneonatal mortality rate of 4.82 per 1000 live births. Postneonatal mortality rates were 4.22 for whites, 5.91 for Asians (relative risk 1.26, 95% confidence interval (CI) 1.04 to 1.53) and 8.20 for Afro-Caribbeans (relative risk 1.78, 95% CI 1.25 to 2.55). Among Asians malformations were common (3.36) and sudden infant death syndrome rare (1.18), in contrast to Afro-Caribbeans among whom the rates were 0.66 and 5.25, respectively. Logistic regression analysis demonstrated a significantly lower risk of sudden infant death syndrome (SIDS) in Asians and significantly raised risks of SIDS in very low birthweight babies and those with unemployed parent(s). Ethnic differences persisted after controlling for maternal age, social class, and birth weight. Studies of sociocultural differences in child rearing practices are needed and may uncover important aetiological factors of sudden infant death syndrome.     

Oxidation therapy: the use of a reactive oxygen species-generating enzyme system for tumour treatment.

Oxygen radicals induce cytotoxicity via a variety of mechanisms, including DNA damage, lipid peroxidation and protein oxidation. Here, we explore the use of a polyethylene glycol (PEG)-stabilised enzyme capable of producing reactive oxygen species (ROS), glucose oxidase (GO), for the purpose of harnessing the cytotoxic potential of ROS for treating solid tumours. PEG-GO (200 U), administered by two intratumoral injections 3 h apart, produced a significant growth delay in subcutaneous rat 9L gliomas as compared with control animals receiving heat-denatured PEG-GO. Rats were protected from systemic toxicity by subsequent i.v. administration of PEG-superoxide dismutase (PEG-SOD) and PEG-catalase. In vivo tumour metabolic changes, monitored using 31P magnetic resonance spectroscopy (31P-MRS) 6 h following initial administration of PEG-GO, revealed a 96 +/- 2% reduction in the ATP/Pi ratio and a 0.72 +/- 0.10 unit decline in intracellular pH. A 3-fold sensitisation of 9L glioma cells in vitro to hydrogen peroxide could be achieved by a 24 h preincubation with buthionine sulphoximine (BSO). This study suggests that oxidation therapy, the use of an intratumoral ROS-generating enzyme system for the treatment of solid tumours, is a promising area which warrants further exploration.     

HLA-DQB1*0301 association with increased cutaneous melanoma risk

Susceptibility to a variety of malignancies has been linked to human leukocyte antigen (HLA) genes, including the HLA class II allele DQBI*0301. To determine whether melanoma risk is associated with HLA class II alleles, molecular oligotyping of HLA class II-DRBI, -DQAI and -DQAI genes was performed for 45 patients with melanoma. The DQBI *0301 allele was present in 56% of melanoma patients vs. 27% of 200 local Caucasian controls. This difference was highly significant (Bonferroni'scorrected chi-square p = 0.003, OR = 3.4). No other class II allele tested was present at significantly increased or decreased frequency in melanoma patients. Furthermore, presence of DQBI*0301 in melanoma patients was associated with advanced disease. Melanoma patients carrying the DQBI*0301 allele presented on average with thicker primary tumors (mean 3.7 mm vs. 1.8 mm, 2-tailed p = 0.02) and were more likely to present with regional or distant metastatic disease (stages III-IV, 44% vs. 5%, chi-square p = 0.003), compared to melanoma patients without DQBI*0301. Risk of melanoma incidence or progression may be influenced by DQBI*0301 or a closely linked gene. © 1994 Wiley-Liss, Inc.     

3-D components of a biological neural network visualized in computer generated imagery. II. Macular neural network organization

Computer-assisted reconstructions of small parts of the macular neural network show how the nerve terminals and receptive fields are organized in 3-dimensional space. This biological neural network is anatomically organized for parallel distributed processing of information. Processing appears to be more complex than in computer-based neural networks, because spatiotemporal factors figure into synaptic weighting. Serial reconstruction data show anatomical arrangements which suggest that 1) assemblies of cells analyse and distribute information with inbuilt redundancy, to improve reliability; 2) feedforward/feedback loops provide the capacity for presynaptic modulation of output during processing; 3) constrained randomness in connectivities contributes to adaptability; and 4) local variations in network complexity permit differing analyses of incoming signals to take place simultaneously. The last inference suggests that there may be segregation of information flow to central stations subserving particular functions.     

Ovine maternal and fetal glomerular atrial natriuretic factor receptors: response to dehydration.

In pregnancy, dehydration produces marked effects on maternal and fetal body water homeostasis including an increase in fetal urinary sodium concentration and excretion. To examine the role of fetal plasma atrial natriuretic factor (ANF) and glomerular ANF receptors in dehydration-induced natriuresis, we compared plasma ANF levels and glomerular ANF binding characteristics in dehydrated and control maternal and fetal sheep. Mean (+/- SEM) maternal and fetal plasma ANF levels in control animals (n = 9) at 132-136 days gestation were 37 +/- 3 pg/ml and 138 +/- 20 pg/ml, respectively. Although mean ANF receptor maximum binding capacities (Bmax) were significantly higher in maternal than in fetal glomeruli (83 +/- 11 vs 34 +/- 12 fmol/mg protein, respectively), the dissociation constants (Kd) for ANF binding were not different (2.7 +/- 0.6 and 3.7 +/- 1.7 x 10(-10) M, respectively). In an additional 9 animals studied after 63 +/- 4 h of water deprivation, maternal plasma ANF levels were significantly lower than in the control group (14 +/- 4 vs. 37 +/- 3 pg/ml), maternal glomerular ANF receptor Bmax values were significantly higher (732 +/- 203 vs. 83 +/- 11 fmol/mg protein), and Kd values were six-fold higher (17.0 +/- 7.1 vs. 2.7 +/- 0.6 x 10(-10) M), although this difference was only marginally significant (p = 0.06). In contrast to the adult, there was a small, nonsignificant decrease in plasma ANF levels and no difference in Bmax or Kd values between the dehydrated and euhydrated fetal animals.(ABSTRACT TRUNCATED AT 250 WORDS)     

A study of the heterogeneity of the mucoepidermoid tumor and the implication for future therapies.

Mucoepidermoid carcinomas are common head and neck neoplasms whose wide distribution includes the major salivary glands, especially parotid, the minor salivary glands within the oropharynx, sites within the larynx, and the submucosal bronchial glands. These tumors are heterogeneous neoplasms composed of intermediate, squamous, and mucous cell subpopulations and have been traditionally classified as low or high grade based on their histological nature and tendency for invasion and metastasis. To gain a better understanding of the heterogeneity of these tumors, we conducted in-depth studies of the different cellular subpopulations obtained from primary human mucoepidermoid carcinomas from various sites, and a derived cell line grown in monolayer culture and as a nude mouse xenograft. Flow cytometric and clonal dilution studies indicate that the intermediate cell behaves as a reserve cell capable of differentiating into either the squamous cell or mucous cell. Immunocytochemical studies of bromodeoxyuridine uptake and Ki-67 antigen expression indicate that whereas the squamous and mucous cells are terminally differentiated and permanently arrested in G0, the intermediate cell actively enters G1 and S. Studies of invasion utilizing a human amnionic membrane indicate that only the intermediate cell is capable of active invasion. Because the mucous and squamous cells are incapable of further division or invasion, therapeutic strategies aimed at differentiating the intermediate cell in vivo into either mucous or squamous directions would serve as useful adjuncts to surgery by reducing the rate of recurrence and the incidence of metastasis.