Occupational exposure of deck crews to carcinogenic agents on crude oil tankers

Occupational exposure to carcinogenic agents on the decks on six Norwegian crude oil tankers was examined in five harbors. The purpose of the study was to evaluate the need for improving the working environment on deck on these tankers. Technical arrangments and the work itself on the deck were observed during loading or unloading. Occupational monitoring was performed by active sampling of benzene, polyaromatic hydrocarbons, and some aldehydes. The crew answered a questionnaire concerning their work, use of protective equipment, and occurrence of acute symptoms. The levels of air-borne carcinogenic agents were low, probably due to closed loading systems on all tankers. However, the seamen reported discomfort during the work that may be related to other chemical agents in the cargo. The seamen were frequently painting with lead chromate paint without using personal protective equipment. This type of chemical exposure should be evaluated.     

Impaired early bone formation in periodontal fenestration defects in dogs following application of insulin-like growth factor (II). Basic fibroblast growth factor and transforming growth factor beta 1

Abstract. Effects of a topically applied growth factor combination on fibroblast migration, collagen fiber formation and bone regeneration were studied in standardized periodontal defects in 4 beagle dogs. Following elevation of facial mucoperiosteal flaps, fenestration defects, 3 mm in diameter, were made through the cortical bone and into the dentin of maxillary and mandibular teeth. Collagen sponges, impregnated with 200 ng insulin-like growth factor II, 20 ng basic fibroblast growth factor and 6 ng transforming growth factor beta 1 were fitted to defects randomly in right or left quadrants and the flaps repositioned and sutured. Contralateral control defects received the collagen with vehicle only. Experimental procedures were staggered to allow observations of healing 3, 7, 10, and 14 days after surgery. Histometric analysis showed no differences in fibroblast and collagen density between control and growth factor defects. Bone regeneration was significantly greater in control than in growth factor defects 10 and 14 days after surgery. The rate of healing generally appeared more affected by intra-dog variations or procedural variations than by the growth factor combination.     

Cardiology

This article describes recent developments in cardiology and cardiovascular disease that are likely to be relevant to primary healthcare professionals and their patients. The following subject areas are covered: Primary prevention: recent developments in pharmaco-logical interventions, drug interactions, and drugs that are likely to cause harm; cardiovascular risk estimation and shared decision making with patients; and new developments in 24-hour ambulatory blood pressure monitoring. Secondary prevention: new models of care, including nurse-led care for the provision of hypertension and secondary prevention clinics; new drugs for the treatment of angina and myocardial infarction; ambulatory electrocardiography for the diagnosis of arrhythmias in primary care; and new developments in the treatment of atrial fibrillation - direct thrombin inhibitors and implantable devices. Tertiary prevention: recent developments in cardiac rehabilitation; recent evidence concerning revascularisation procedures and appropriateness criteria for referral; and implantable defibrillators.     

Isolation of human immunodeficiency virus (HIV) from plasma during primary HIV infection

Human immunodeficiency virus (HIV) has been isolated from plasma in 6 of 7 patients showing clinical symptoms of a primary HIV infection. Parallel cultures from peripheral blood mononuclear cells (PBMC) yielded virus in 5 patients. In one case, virus could only be isolated from the cerebrospinal fluid but not from peripheral blood. Detectable viremia was transient and preceded the appearance of HIV specific antibodies. After cessation of acute symptoms, the frequency of HIV isolations was similar to that of asymptomatic carriers (23 and 26%, respectively). The role of the immune response in terminating detectable viremia remains to be established.     

Cardiac auscultation training of medical students: a comparison of electronic sensor-based and acoustic stethoscopes

Background  

To determine whether the use of an electronic, sensor based stethoscope affects the cardiac auscultation skills of undergraduate medical students.     

Immunohistochemical and molecular analysis of p53, RB,and PTEN in malignant peripheral nerve sheath tumors

The molecular basis of both sporadic and neurofibromatosis type 1 (NF1)-associated malignant peripheral nerve sheath tumors (MPNSTs) is yet largely undetermined. Therefore, we analyzed a series of 12 MPNSTs - including two cases which arose in the setting of NF1 - for molecular alterations in the p53, retinoblastoma ( Rb), and PTEN tumor suppressor genes. Furthermore, the immunohistochemical expression of p53, RB, and PTEN protein was examined in these tumors. One mutation (8%), an A to T transversion leading to an amino acid exchange, was found in exon 5 of the p53 gene in a sporadic MPNST. In two other sporadic tumors (20%), loss of heterozygosity (LOH) of the p53 gene occurred. Nuclear overexpression of p53 protein was observed in ten tumors (83%). Loss of RB protein expression was seen in two MPNSTs (17%), and LOH of the Rb gene was detected in four tumors (44%), including the two NF1-associated MPNSTs, one of them showing concomitant loss of RB protein expression. No mutation in the PTEN gene was detected, and cytoplasmic immunoreactivity for the PTEN protein was maintained in eight MPNSTs (67%). We suggest that alterations in the p53 and RB pathway, both are essential in controlling the cell-cycle progression, are critical points in the tumorigenesis of sporadic and NF1-associated MPNSTs, whereas the PTEN gene seems to play no significant role in this process.     

Pediatric head injuries caused by traffic accidents

In an unselected series of 488 patients with head injuries referred to a general surgical department, there were 126 children aged 0–19 years whose head injuries were a result of traffic accidents. In age group 0–4 years, only 23% of the head injuries were due to traffic accidents. In age groups 5–9, 10–14, and 15–19 years, however, traffic accidents were the main cause of the injuries, being responsible for 47%, 65% and 82% of the cases respectively. Both age groups 5–9 and 10–14 years had an unusually high proportion of bicycle injuries, while motorcycle and automobile accidents were the leading causes of injury in age group 15–19 years. Eight children (6%) died as a result of head trauma. Furthermore, among the survivors there were 8 children with severe head injuries (post-traumatic amnesia lasting 24 h), the rest being minor head injuries. All the survivors but one returned to school and achieved reasonable performances. Repeated follow-up studies at 3 months, 1 and 5 years, including interviews with the parents, disclosed that several of the children had headache, dizziness and other complaints. These subjective complaints subsided with time, but with different patterns, in the younger and older age groups. It is concluded that the postconcussional syndrome is not uncommon in children, but it may be better tolerated and resolves more completely with time than in adults. Eight children (7%) had one seizure or more during the 5-year follow-up period.