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P Jordan

Publications and source records attributed to P Jordan.

At least 109 records · Page 6Linked to original sources
PubMed1987

Computer-aided information system to support direct patient care. The application of a hand-held data collector in a department of medicine.

In the pilot study, described herein, we have tried to develop a computerized system to assist and improve medical and nursing care. Our major goal was to bring the computer to the patient's bedside. This was achieved by a Hand-Held Data Collector, which is easy to carry and operate, and has a big enough memory. In this preliminary study, we have developed appropriate software specifically designed to reflect the daily activities and needs of a department of medicine. Using this software, we have demonstrated that all 'clinical events' and routine tasks of the department can be managed via the Hand-Held Data Collector.

Computer Systems↗
PubMed1987

Effect of patterned surfaces of adhesive islands on the shape, cytoskeleton, adhesion and behaviour of Swiss mouse 3T3 fibroblasts.

A pattern of circular islands of adhesive substratum can be used to control cell shape and behaviour. We have shown previously that the proportion of Swiss 3T3 cells that synthesize DNA varies with the area of the island to which they are attached, within the range 500-5000 microns2. In this paper we investigate the cytoskeleton and adhesions of cells on islands using a variety of techniques including phalloidin staining and interference reflection microscopy. Islands of area 2000 microns2 or less constrain cell shape, and cause focal contacts and actin microfilament bundles to accumulate in a circle at the margin. These changes are most obvious in islands of about 1000 microns2, in which a complete ring of adhesion is sometimes formed in the periphery of the cell. This peripheral distribution is less common in cells on even smaller islands, and the focal contacts become smaller and less numerous. It is not yet clear whether any of these structural changes are associated directly with the proliferative stimulus due to contact with the substratum. However, we expect that the use of patterned substrata will contribute to the study of how cell shape and structure regulate many cell functions.

Actins↗
PubMed1987

Duodenal varices as a cause of massive upper gastrointestinal bleeding.

Duodenal varices are an uncommon but serious manifestation of portal hypertension. Our management of three patients with massive bleeding due to duodenal varices stimulated a review of this subject. Thirteen cases of this condition were previously reported. Endoscopic examination of the entire duodenal mucosa is essential to document bleeding from duodenal varices. Medical therapies, including vasopressin and endoscopic sclerotherapy, have had limited success in controlling active duodenal variceal bleeding. Duodenal varix suture ligation or resection also resulted in a high rate of rebleeding. End-to-side portocaval shunt was the most effective procedure in stopping acute and subsequent bleeding in patients with duodenal varices. Despite therapy with or without portosystemic shunt, mortality risk is high in Child's class C patients and in patients with emergency duodenal variceal bleeding.

Adult↗
PubMed1986

Evidence for two distinct mechanisms of anchorage stimulation in freshly explanted and 3T3 Swiss mouse fibroblasts.

When single cells were allowed to attach to circular islands of adhesive substratum, their proliferation was strongly dependent on island area over the range 500 micron2 to 5000 micron2. The number of freshly explanted whole mouse embryo fibroblasts that performed DNA synthesis corresponded closely with a simple geometrical measure of area of cell surface exposed to the medium: freely suspended cells were only slightly less stimulated than attached cells exposing an equal surface area; hemispherical cells were less stimulated than cells of any other shape. In contrast, 3T3 cells were stimulated sixfold by islands too small to allow any increase in area. These experiments show that anchorage can stimulate by two different mechanisms. They offer a general method of measuring substrate contact stimulation.

Animals↗
PubMed1986

Silica and oesophageal cancer.

The growth of animal cells in culture can be stimulated very powerfully when they are allowed to extend upon a solid surface. In normal fibroblasts, the maximum is reached either on a plane surface with an area of 2500 micron 2 or on a narrow fibre with a length of 250 micron. This growth-stimulating effect of fibres could help to explain how asbestos causes cancer. All asbestiform minerals are complex mixtures of different lengths, but siliceous macrohairs with a uniform length are borne by several species of the grass genus Phalaris. Some of these species are common contaminants of the bread eaten in a part of Iran where oesophageal cancer has an unexplained high incidence. A pure preparation of 200 micron silica fibres from one of these species is a powerful promoter of cancer in the skin of mice. Similar fibres from millet (Seteria italica) are associated with the same disease in China, and plant silica has long been known to be associated the it in South Africa. In addition, a rare thoracic tumour, which normally only occurs after exposure to asbestos, has been detected among sugarcane farmers in the United States and in India; fine silica fibres are liberated into the air during the harvest.

Animals↗
PubMed1985

Affective disorders in referred children and younger siblings of manic-depressives. Mode of onset and prospective course.

We studied 68 referred juvenile offspring or siblings of adult bipolar patients. Mean age at onset of affective and related disturbances was 15.9 years (range, 6 to 24 years). Although four of the ten prepubertal children had hypomanic features, full-blown manic psychosis did not appear before puberty. In the sample at large, 12 were classified as dysthymic and ten as cyclothymic. Eleven additional subjects with polysubstance abuse, who at onset did not meet criteria for affective disorder, were reclassified as having either a dysthymic or a cyclothymic disorder during follow-up. Of the remaining patients--24 depressive, eight manic, and three mixed state--71% experienced recurrences; mood-incongruent features, present in four cases at onset, recurred in only one patient during subsequent episodes. Overall, half the sample evidenced signs of bipolarity during a mean prospective follow-up period of three years.

Acute Disease↗
PubMed1984

Translational repression of mRNA for eucaryotic elongation factors in Friend erythroleukemia cells.

Poly(A)-containing mRNA was prepared from polyribosomes and postpolyribosomal messenger ribonucleoprotein particles (mRNP) from Friend erythroleukemic cells. Both mRNA types were translated in vitro and the 35S-labeled translation products examined by two-dimensional gel electrophoresis. Among the most abundant untranslated mRNA species was the mRNA coding for eucaryotic elongation factor Tu (eEF-Tu). In addition, the mRNA for eucaryotic elongation factor Ts was also present in Friend cells in untranslated form. Calculations based on translation assays indicate that eEF-Tu represents about 15% of the translation products of RNP mRNA and that approximately 40% of the eEF-Tu synthesized in vitro is encoded by translationally repressed mRNA. This repressed mRNA can be activated by addition of cycloheximide to cell cultures. At the level of 0.1 micrograms/ml, cycloheximide was found to inhibit cellular protein synthesis by about 50% while augmenting the relative rate of eEF-Tu synthesis 1.6-fold. This result suggested that eEF-Tu mRNA might initiate poorly. However, addition of supersaturating levels of mRNA to a reticulocyte lysate augmented eEF-Tu synthesis about twofold, while generally depressing the synthesis of other proteins by about 40%. Thus the storage of large amounts of eEF-Tu mRNA in vivo is unlikely to be due directly to the ineffectiveness of the mRNA in competing for the initiation machinery of the cell. The results presented in this report suggest that the supply of active eEF-Tu in erythroleukemic cells is controlled, at least in part, by a translational mechanism.

Animals↗
PubMed1983

Efficacy of oral and systemic antibiotic prophylaxis in colorectal operations.

A cooperative Veterans Administration study of the septic complication rate during large-bowel surgery was undertaken in two groups of patients. The first group received oral neomycin and erythromycin base plus parenteral placebo; the second, the oral antibiotics plus parenteral cephalothin sodium. During a five-year period, 1,128 patients were studied. The overall septic complication rate was 7.8% in patients receiving only oral antibiotics, and 5.7% in patients receiving both oral and parenteral antibiotics. This difference was not significant. The only significant finding was a greater incidence of fever of unknown origin in patients receiving only oral antibiotics. None of those patients were treated with additional antibiotics, and all fevers cleared spontaneously. There seems to be no discernible benefit from adding parenteral antibiotic prophylaxis when performing elective colon surgery if appropriate mechanical cleansing and oral neomycin and erythromycin therapy are employed.

Administration, Oral↗
PubMed1982

Silica fragments from millet bran in mucosa surrounding oesophageal tumours in patients in northern China.

Millet bran is a component of the diet in the area of highest oesophageal cancer incidence in northern China. Millet bran was found to contain up to 20% by weight of silica; some of this silica occurs as friable sheets or sharply-pointed fibres. These types of silica in millet bran are the most likely source of an unusual contamination with fragments of silica found in the oesophageal mucosa surrounding tumours in patients in northern China. A group of mucosal samples analysed together contained over 5,000 particles/g (100 parts per million by weight), ten times as many as were found in tissue from normal controls taken at necropsy in London. The modal diameter was 10 microgram (1-70 microgram). The particles were in the body of the mucosa and were not simply a surface contaminant. Silica fragments and fibres of similar size originating from other plant species occur in the diet in the two other regions of greatest incidence of oesophageal cancer, the Transkei and Iran. If such fragments enter the mucosa, they must cause some degree of trauma, and they may also be able to stimulate proliferation by providing anchorage. These findings suggest the possibility that silica particles might be involved in the aetiology of oesophageal cancer.

Adult↗
PubMed1982

Routine focal mollusciciding after chemotherapy to control Schistosoma mansoni in Cul de Sac valley, Saint Lucia.

Concluding results of a 10-year schistosomiasis control programme in Cul de Sac valley, Saint Lucia, are described. After an area-wide mollusciciding campaign (1970-75), and a surveillance/treatment programme supplemented with selective population chemotherapy in 1975 and 1976, prevalence rates of Schistosoma mansoni were reduced to low levels. To prevent a resurgence of transmission a cost effective routine focal mollusciciding programme, suitable for public health implementation was evaluated from 1977 to 1981. Streams and main collector drains in banana fields, considered to be potential S. mansoni transmission sites, were treated every four weeks with Bayluscide 6076 emulsifiable concentrate (Clonitralide). Snail populations were effectively controlled in the treated areas but large numbers were present where no treatment was given. Only 0 X 06% of sentinel snails became infected. Prevalence of infection in the human population remained low (over-all 5%) and intensity of infection at a level not normally associated with schistosomal disease. Since control started 10 years earlier the level of potential contamination has fallen by 92% in high transmission areas. The four-year programme cost US+12,909 of which 54% was for molluscicide, 27% for labour and 19% for transport, equipment and sundries. The average annual cost per head of population was US+0 X 46.

Adolescent↗
PubMed1982

Evaluation of chemotherapy in the control of Schistosoma mansoni in Marquis Valley, Saint Lucia. I. Results in humans.

Hycanthone at a dose of 2.5 mg kg body weight was given in 1973 and 1974 to persons found by a sedimentation concentration technique to be excreting Schistosoma mansoni eggs. In a further two campaigns oxamniquine was used (15 mg/kg body weight). The last treatment was given after the 1976 survey and stools of children were re-examined annually but not further treatment was planned. In six villages prevalence remained low, at 4%, 4 years later, in two it increased to 10%, and in two others after 3 years it was 23% and further treatment was offered. Factors affecting renewed transmission and the rate prevalence builds up were investigated and found to be low attendance rate for treatment, greater use of the river water and, possibly, infected immigrants. But if prevalence builds up slowly, retreatment may be necessary only every 3-4 years at an estimated annual cost of 40 cents per person protected.

Adolescent↗
PubMed1982

Value of individual household water supplies in the maintenance phase of a schistosomiasis control programme in Saint-Lucia, after chemotherapy.

Between 1970 and 1975, the incidence of new Schistosoma mansoni infections was reduced in 5 villages after each household was provided with its individual water supply and community laundry shower units were made available. In 1975, 1976, and 1977 chemotherapy with oxamniquine was offered to persons found to be infected. Transmission was reduced further and remained at a low level for the next 4 years, with no sign of an increase in spite of the reservoir of infection remaining after therapy and a poor level of sanitation in the villages.Thus, properly maintained water supplies appear to be effective in maintaining transmission at a low level during the maintenance phase of a schistosomiasis control programme, after chemotherapy. Sporadic new infections must be anticipated among children, but these will probably be of low intensity and associated with minimal morbidity.

Adolescent↗
PubMed1981

Visual motion cues in prismatic adaptation: evidence of two separate and additive processes.

The present study was based on the assumption that there are two visual channels which provide separate contributions to visuo-motor recalibration following prismatic displacement of the visual field. The functional properties of the two channels were assumed to conform to predictions from the two motion-analyzing systems models of visual motion perception. The results of the present study confirmed the predictions of the model. Whatever the type of illumination (continuous or stroboscopic) central vision utilizes only cues provided by visual exposure of the arm pointing to a stationary target. Peripheral vision utilizes only cues from visual exposure of the arm freely moving against the homogeneous background but this can be prevented by stroboscopic illumination. In peripheral vision, movement cues provided by exposure of a passively moved arm are not processed. In contrast, the processing of visual cues in central vision is unaffected by whether the movements are active or passive, provided that a stationary target is present. The effects of the two channels may be additive or competitive depending on the conditions. Experimental and theoretical implications are discussed.

Cues↗