Search PubMed⌕ Search

Biomedical subjects

M Cameron

Publications and source records attributed to M Cameron.

At least 55 records · Page 3Linked to original sources

Blood transfusion as a cause of leucocytosis in critically ill patients.

The diagnosis of infection in the intensive care unit is confounded by the presence of non-infectious causes of leucocytosis. Unless such causes are recognised, time and effort will be spent on unnecessary investigations and treatments. In a prospective study we have shown that the transfusion of blood frequently (45/50 patients) causes an acute leucocytosis in such patients. This effect was not seen in 8 patients who received plasma. Blood transfusion should be added to the list of non-infectious causes of leucocytosis in the critically ill.

Adult↗

Vehicle crashworthiness ratings in Australia.

The paper reviews the published vehicle safety ratings based on mass crash data from the United States, Sweden, and Great Britain. It then describes the development of vehicle crashworthiness ratings based on injury compensation claims and police accident reports from Victoria and New South Wales, the two most populous states in Australia. Crashworthiness was measured by a combination of injury severity (of injured drivers) and injury risk (of drivers involved in crashes). Injury severity was based on 22,600 drivers injured in crashes in the two states. Injury risk was based on 70,900 drivers in New South Wales involved in crashes after which a vehicle was towed away. Injury risk measured in this way was compared with the "relative injury risk" of particular model cars involved in two car crashes in Victoria (where essentially only casualty crashes are reported), which was based on the method developed by Folksam Insurance in Sweden from Evans' double-pair comparison method. The results include crashworthiness ratings for the makes and models crashing in Australia in sufficient numbers to measure their crash performance adequately. The ratings were normalised for the driver sex and speed limit at the crash location, the two factors found to be strongly related to injury risk and/or severity and to vary substantially across makes and models of Australian crash-involved cars. This allows differences in crashworthiness of individual models to be seen, uncontaminated by major crash exposure differences.

Acceleration↗

Feasibility and efficacy of sodium reduction in the Trials of Hypertension Prevention, phase I. Trials of Hypertension Prevention Collaborative Research Group.

Phase I of the Trials of Hypertension Prevention was a multicenter, randomized trial of the feasibility and efficacy of seven nonpharmacologic interventions, including sodium reduction, in lowering blood pressure in 30- to 54-year-old individuals with a diastolic blood pressure of 80 to 89 mm Hg. Six centers tested an intervention designed to reduce dietary sodium to 80 mmol (1800 mg)/24 h with a total of 327 active intervention and 417 control subjects. The intervention consisted of eight group and two one-to-one meetings during the first 3 months, followed by less-intensive counseling and support for the duration of the study. The mean net decrease in sodium excretion was 43.9 mmol/24 h at 18 months. Women had lower sodium intake at baseline and were therefore more likely to decrease to less than 80 mmol/24 h. Black subjects were less likely to decrease to less than 80 mmol/d, independent of sex or baseline sodium excretion. The mean (95% confidence interval) net decrease associated with treatment was -2.1 (-3.3, -0.8) mm Hg for systolic blood pressure and -1.2 (-2.0, -0.3) mm Hg for diastolic blood pressure at 18 months (both P < .01). Multivariate analyses indicated a larger systolic blood pressure effect in women (-4.44 versus -1.23 mm Hg in men), adjusted for age, race, baseline blood pressure, and baseline 24-hour urinary sodium excretion (P = .02). Dose-response analyses indicated an adjusted decrease of -1.4 mm Hg for systolic blood pressure and -0.9 mm Hg for diastolic blood pressure for a decrease of 100 mmol/24 h in 18-month sodium excretion. These results support the utility of sodium reduction as a population strategy for hypertension prevention and raise questions about possible differences in dose response associated with gender and initial level of sodium intake.

Adult↗

Growth factors interact with estradiol and gonadotropins in the regulation of ovarian cancer cell growth and growth factor receptors.

The factors controlling cell growth in epithelial ovarian cancer (OV Ca) remain poorly defined. Epidemiological evidence suggests that gonadotropins and estrogens may be important in the development of OV Ca. We have established permanent cultures of OV Ca cells from a mesenteric metastasis of an ovarian papillary adenocarcinoma. The growth of these cells was increased 20-60% (p < 0.01) by picomolar concentrations of 17 beta-E2 (but not by 17 alpha-E2) and 0.1 to 1 microgram/mL of hCG (but not hFSH). Both EGF and IGF-1 increased cell growth, and a maximal effect of 3- to 5-fold increase in cell number was observed. Under conditions in which the growth responses to EGF and IGF-1 were submaximal, E2 (0.1 to 100 nM) produced a concentration related increase in the growth response to IGF-1 and EGF. Ten nM E2 increased the responses to EGF and IGF-1 more than 2-fold. In combination, E2/hCG enhanced the growth response to EGF but not to IGF-1. Estradiol increased the Ka of the EGF receptor approximately 2-fold (p < 0.01) and increased the number of receptors/cell for IGF-1 approximately 50% (p < 0.01). While hCG had no effect on EGF receptor binding parameters, it increased the Ka of the IGF-1 receptor and enhanced the effect of E2 on IGF-1 receptor number. These studies suggest that E2 and hCG may regulate cell growth responses of OV Ca cells to IGF-1 and EGF. These changes may be exerted at least partly through modulation of properties of receptors for the two growth factors.

Adenocarcinoma, Papillary↗

[Reconstruction of the cruciate ligaments with allogeneic transplants. Techniques, results and perspectives].

The authors have used allografts for reconstruction of the cruciate ligaments in over 600 cases since 1985. Advantages are the reduced operative trauma and the unlimited availability of high-quality grafts even in multiple ligament reconstructions. Arthroscopic techniques are available for reconstruction of the anterior and the posterior cruciate ligament, which makes arthrotomies and large skin incisions unnecessary. The grafts of choice are the bone-patellar tendon-bone preparation and the Achilles tendon with bone bloc. No specific complications were observed with the use of allograft material in this series. Results show a high subjective acceptance of the procedure among the patients, with a high rate of return to pre-injury sports activities following ACL reconstruction. Objective stability was restored in over 70% of these cases. All cases with posterior instability had 3+ posterior drawer preoperatively. At follow-up, almost normal stability had been restored in 50%. Further research must focus on the biological processes that take place during incorporation of these tissues and on better techniques of graft processing and sterilisation. At present, the risk of disease transmission must be considered and discussed with the patient.

Adolescent↗

Health record completion guidelines. American Health Information Management Association.

It is a pleasure to introduce this important project report to the American Health Information Management Association (AHIMA) membership. Analyzing records for omissions, notifying physicians of needed information, counting delinquent records, and pursuing late documentation are some of the biggest chores in today's health information management departments. And they are chores that take time away from other priorities--managing, analyzing, and presenting health data, planning and implementing computerization, assessing and meeting customer needs. The heart of this statement is simple: it points out that there are other options to the traditional, detailed, record-by-record analysis. And those options may give us the results we need--timely and complete health records--while freeing up valuable staff time for other priorities. Take a serious look at the statement. If you are eager to make a change in your department's practices in records analysis and completion, it will back you up. If you are comparing the value of your department's records completion work to its benefit, this statement will give you ideas for change. And if you don't think you'd ever challenge tradition, this statement will give you food for thought. An added value to this statement is the fact that the ideas in it, and the very statement itself, are the product of our own profession. We are fortunate that leading-edge practitioners gave their expertise to the entire profession. The members of the strategy group for this project are listed above, we thank them for their wisdom.

Communication↗

Isolation and characterization of a repetitive DNA element from the genome of the human filarial parasite, Brugia malayi.

The genome of the human filarial parasite Brugia malayi contains at least two major repetitive DNA elements. One, referred to as the HhaI family, consists of 10(4)-10(5) tandemly arrayed copies per haploid genome of a monomer of 322 base pairs and does not contain a cleavage site for the restriction endonuclease MboI. We constructed a library of MboI-digested genomic B. malayi DNA in BamHI-cut M13mp18 resulting in the exclusion of the HhaI repeat family from the library. Hybridization of this genomic library with nick-translated genomic DNA yielded several copies of a repeat family which we have named the BmMboI family. From sequence analysis of more than 50 monomers, which differ from each other in sequence and length, we have been able to divide the monomers into several regions based on the level of sequence conservation. Southern blot analyses of B. malayi genomic DNA digested with a variety of restriction endonucleases and probed with the isolated repeat demonstrate multiple bands of varying sizes except with HindIII-cut DNA, where the repeat is found only in very high-molecular-weight DNA.

Animals↗

The use of seclusion: a comparison of two psychiatric intensive care units.

The use of seclusion within a psychiatric intensive care unit in a South Australian metropolitan mental hospital was documented over a ten week period. The seclusion rate within the unit was 32% of all admissions and 34% of new admissions. The overall seclusion rate for the hospital was 5.4% of all admissions and 6.3% of new admissions, somewhat higher than in the United Kingdom but considerably lower than in the Eastern United States. A comparison was then made between consecutive new admissions (30 secluded and 30 non-secluded) to this unit and to a similar unit without a seclusion room in the other mental hospital in the State. Although seclusion offered no clear advantages in terms of duration of admission, levels of medication or relapse rates, it appeared to reduce the level of dangerousness in the unit, thereby enhancing staff morale. The overall mean daily total of neuroleptic medication was about 1,200 mg chlorpromazine equivalent, somewhat less than in comparable units in the United States and Europe.

Adult↗

Effective dietary intervention in hypertensives: sodium restriction and weight reduction.

A Dietary Intervention Study of Hypertension (DISH) was undertaken to determine whether patients whose high blood pressure had been controlled pharmacologically for a period of more than 5 years could maintain that control with sodium restriction or weight reduction instead of drugs. Four hundred ninety-six patients, classified by degree of overweight, were randomly assigned into one of seven groups. Included were those who would be withdrawn from antihypertensive medication and receive intervention for either sodium restriction or weight reduction. After 8 weeks of intervention, an average reduction of 24-hour urinary sodium output from a baseline of 158 mEq to 106 mEq (p less than .001) and from 130 mEq to 96 mEq (p less than .01) was achieved for the overweight and nonoverweight groups, respectively. That decline was still maintained at 56 weeks. Dietary estimates, obtained by analysis of 3-day food records, underestimated urinary output by an average of 12%, with blacks more likely to underestimate than whites, and the overweight more likely to underestimate than the nonoverweight. An average 10-lb weight loss was achieved, with no difference between men and women. Weight declined for 32 weeks, then leveled off and was maintained up to 56 weeks, indicating that sodium intake modification can be accomplished faster than weight reduction. Modest sodium restriction and weight reduction are feasible and achievable in a free-living population and have a positive effect on control of hypertension.

Clinical Trials as Topic↗

Clonic hemifacial spasm from posterior fossa arteriovenous malformation.

A 21 year old woman presented with a two year history of right sided clonic hemifacial spasm. Investigations showed a large arteriovenous malformation on the right side of the posterior fossa and surgical exploration was undertaken. Early follow-up at six months showed a complete cure.

Facial Muscles↗