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J A Walsh

Publications and source records attributed to J A Walsh.

At least 19 recordsLinked to original sources
PubMed1995

Setting priorities for the Children's Vaccine Initiative: a cost-effectiveness approach.

To help the Children's Vaccine Initiative (CVI) achieve its goal of new and improved children's vaccines, we developed and applied a cost-effectiveness model to set priorities for vaccine development. The model measures the health benefits in additional Quality-Adjusted Life Years (QALYs) gained by the combined birth cohorts of all developing countries over an assumed useful life of a proposed vaccine (generally 10 years). It measures costs as the net cost of developing, procuring, and administering the vaccine to the same population and time frame compared to the status quo (the current vaccine, if any). It weights each dollar of in-kind allocation of the existing health infrastructure less heavily than a dollar cash outlay to purchase new vaccine to reflect severe constraints on foreign exchange and non-personnel costs. It expresses cost-effectiveness as the net cost per QALY. The model was applied to 13 candidate vaccines selected by the CVI for initial analysis on the basis of their near-term feasibility. The five most cost-effective improvements, each of which could generate a QALY inexpensively (below $25 per QALY), were an early-administration or an early two-dose measles vaccine, slow release tetanus toxoid (for women), improved typhoid vaccine, and hepatitis B combined with diphtheria-tetanus-pertussis vaccine.

Child, Preschool↗
PubMed1992

A retrospective analysis of infra-inguinal arterial reconstruction: three year patency rates.

Primary infra-inguinal arterial reconstructions were reviewed for primary patency and outcome of thrombosis in 144 patients. Distal anastomoses in these patients were to the popliteal artery and were above the knee in 63, below the knee in 53 and at the tibial level in 28. The treatment used was: polytetrafluoroethylene (PTFE) in 33 cases, PTFE with an interposition vein cuff in 29 cases, autogenous saphenous vein (ASV) in situ in 47 cases, and reversed technique in 26 cases. Life table analysis showed a 59% overall primary patency at 3 years. Patency rates of above knee anastomoses (65%) and below knee (61%) were statistically different from the tibial anastomoses (42%, P = 0.005). In both above and below knee popliteal anastomoses there was a statistically significant difference in the patency of ASV and the PTFE/vein cuff technique (P = 0.0006) but there was no difference between ASV and PTFE. There was no difference in patency rates for the various types of grafts with tibial anastomoses. Data were analysed at 3 years, taking into account the variables of smoking, diabetes or indications for surgery respectively and no difference was found in patency. The number and calibre of the run-off vessels did not influence patency significantly, hence anastomosis to any good quality vessel regardless of run-off is recommended. The poor results with the interposition vein cuff technique are unexplained but this study suggests that the technique should be reserved for anastomoses below the popliteal artery.

Adult↗
PubMed1991

Evaluation of efficacy and safety of an inactivated virus vaccine against feline leukemia virus infection.

An inactivated virus vaccine was developed for prevention of FeLV infection in domestic cats. When given in 2 doses, 3 weeks apart, to cats that were greater than or equal to 9 weeks old at the time of first vaccination, the vaccine prevented persistent viremia from developing in 132 of 144 (92%) vaccinates after oronasal challenge exposure with virulent FeLV. In contrast, persistent viremia developed after oronasal challenge exposure with FeLV in 39 of 45 (87%) age-matched nonvaccinated control cats. Transient viremia, indicated by early detection of p27 by ELISA in serum of cats protected from persistent viremia at 12 weeks after challenge exposure, was found in 10 of 132 (8%) vaccinates. Cats that were aviremic 12 to 16 weeks after challenge exposure were examined for reactivation of latent FeLV infection; 4 weekly doses of methylprednisolone were administered, followed by in vitro culture of bone marrow cells. Latent infection was readily reactivated in 6 of 8 (75%) nonvaccinated control cats that had been transiently viremic after challenge exposure. However, latent infection was reactivated in only 5 of 48 (10%) protected vaccinates, and in none of 38 vaccinates in which transient viremia had not been detected. In a safety field trial, only 34 mild reactions of short duration were observed after administration of 2,379 doses of vaccine to cats of various ages, breeds, and vaccination history, for a 1.43% reaction rate. Results indicate that the aforementioned inactivated virus vaccine is safe and efficacious for the prevention of infection with FeLV.

Animals↗
PubMed1991

Dermatoglyphics and acute lymphocytic leukemia in children.

Cellular features of acute lymphocytic leukemia (ALL) in children suggest that it originates in abnormal embryogenesis. Because palmar flexion creases develop in the embryo at the same time as the blood-forming cells, and because both arise from mesodermal tissue, insults to the embryo that may lead to leukemic changes in the blood-forming cells may also result in aberrant palmar crease patterns. This study investigated the relationship between aberrant palmar creases and ALL in children who developed leukemia at age 6 years or younger. Odds ratios and chi squares demonstrated significant differences in bilateral aberrant palmar creases between ALL children and relatives (P less than .025). Differences were not explained by familial clustering of aberrant creases. These results support the theory that the insult occurred during pregnancy, probably in the first trimester. There were no significant differences in either bilateral or unilateral aberrant palmar creases between ALL children and their siblings. All children with bilateral aberrant creases had a higher incidence of central nervous system involvement (50%) than those without bilateral aberrant creases (6%). This may reflect a preleukemic change in utero before the time the blood-brain barrier has been established.

California↗
PubMed1990

Vascular outflow resistance and angiographic assessment of lower limb arterial reconstructive procedures.

In an attempt to predict early graft occlusion secondary to poor distal run-off, the outflow resistance was measured intra-operatively and compared with the intra-operative angiogram in 50 patients undergoing lower limb bypass procedures. With arterial inflow occluded, 60 mL of plasmalyte was infused via a catheter and the resultant pressure generated in the graft was measured through a second catheter connected to a pressure transducer and recorder. Using the infusion rate and integrated pressure value, outflow resistance was calculated. High resistance measurements were defined as grafts with outflow resistance greater than 1.1 mmHg/mL per min, low measurements were defined as values less than 0.5 mmHg/mL per min and intermediate measurements were those in the range 0.5-1.1 mmHg/mL per min. Angiograms were classified independently of resistance measurements by scoring the numbers of run-off vessels crossing the ankle and stenoses, with subsequent assignment of the patient to one of three groups with either low, intermediate, or high probability of graft failure. Early graft failure was defined as cessation of graft function within 3 months of surgery. Early graft failure occurred in both cases with high outflow resistance and in seven of 44 with low outflow resistance. Of these nine occluded bypasses, six had been placed in the high probability of occlusion category on angiographic appearance and three in the intermediate category. Assessment of angiographic appearance and prediction of patency on a prospective basis had a sensitivity rate of 67% and a specificity rate of 78%. The corresponding sensitivity and specificity rates with resistance measurements were 22% and 100%, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1988

Selectivity within primary health care.

While great strides have been made in improving socioeconomic conditions in the developing world, prospects for health for all remain remote. Resources are few, and difficult decisions must be made concerning the priorities for their use. This paper addresses several topics involved in making these choices including the methods for determining priorities and ensuring effectiveness of resource use. First, prioritizing. Information is needed concerning the prevalence, mortality, morbidity, feasibility and cost of control for each disease of importance in the area under consideration. Second, the use of technology. In discussion of health care some have denigrated the concentration many programs have placed on specific methods and technologies. Nevertheless, technological advances, while some have had detrimental results, have often led to improved living conditions; for example, improved seed and fertilizer use, improved water pumps, family planning efforts. These technologies required a larger investment in management, financial and communication systems. Health interventions are frequently more various and complex than these and need a similar support system for impact. However there are many shortcomings in health services; the paper looks at some of these learnt through experience, and concludes that the lack of impact on health of large scale health programs that have provided selective interventions is probably related to an inadequate recognition of the importance of community and political involvement and of the necessary social, cultural, financial, management and administrative underpinnings.

Developing Countries↗
PubMed1988

Inter-relationships between vascular thromboxane and prostacyclin synthesis.

We have measured the effect of various concentrations of arachidonic acid on the rates of synthesis of prostacyclin and thromboxane in human umbilical artery slices. Increasing concentrations of arachidonate increased the rate of thromboxane synthesis, but had no effect on the rate of prostacyclin synthesis. However, in dexamethasone-treated artery slices, arachidonate increased the rate of thromboxane and prostacyclin synthesis. Overall, it was demonstrated that arachidonate can alter the ratio of prostacyclin/thromboxane synthesis in untreated artery slices and, by inference, arachidonate can alter the thrombogenicity of vascular endothelium. A mechanism is proposed to explain the arachidonate-induced changes in the prostacyclin/thromboxane ratio.

Arachidonic Acid↗
PubMed1987

Effect of 50 mg enteric-coated aspirin (Astrix) on thromboxane and prostacyclin synthesis.

Although low-dose soluble aspirin can be recommended as a useful anti-thrombotic drug regimen in patients with vascular disease, enteric-coated preparations have a theoretical advantage for aspirin preparations which are to be ingested daily for many years. We have demonstrated that a 50 mg enteric-coated aspirin formulation (Astrix) which has an absorption rate much lower than soluble aspirin, is sufficient to inhibit platelet thromboxane synthesis while causing no major decrease in vascular prostacyclin synthesis.

Aspirin↗
PubMed1987

Transluminal balloon angioplasty in diabetic peripheral vascular disease.

Transluminal (balloon) angioplasty of iliac or superficial femoral stenoses in 18 diabetic patients resulted in a significant improvement in ankle/brachial systolic pressure index with marked symptomatic improvement in 16, little change in one and deterioration requiring arterial bypass surgery in one patient. Follow-up for 12 months or more showed that the initial good results were sustained despite a downward drift in ankle pressures. These findings indicate that transluminal angioplasty has a useful place in the management of proximal atherosclerotic stenotic lesions in diabetic patients with symptomatic peripheral vascular disease.

Aged↗
PubMed1986

Cross validation of some psychometric properties of the CSQ and its differential return rate as a function of token financial incentive.

The Consumer Satisfaction Questionnaire (CSQ) was developed by Larsen, Atkisson, Hargreaves, and Nguyen (1979) and has been mentioned as a possible "standard scale" for the evaluation of consumer satisfaction with mental health treatment because of its unidimensionality, reliability, validity and ease of use. A mail survey of ex-clients who had terminated treatment during the preceding year from one of six offices of a regional mental health center in the Rocky Mountain area strongly cross-validated these characteristics as well as other results from the consumer satisfaction literature. In addition, based upon evidence from marketing research, a randomly selected half of the ex-clients surveyed was offered a token inducement of two cents for returning the questionnaire while the other half was not. A significantly greater proportion of ex-clients who received the token inducement returned their questionnaires than did those who had not. This approach appears to be promising and further research with it is indicated.

Community Mental Health Centers↗
PubMed1986

Methods for quantitative and qualitative evaluation of vaginal microflora during menstruation.

The quantitative and qualitative changes in the bacterial flora of the vagina during menstruation have received inadequate study. Similarly, the effect of vaginal tampons on the microbial flora as well as the relationship between the microbial flora of the vagina and that of the tampon has not been adequately evaluated. The purposes of the present study were (i) to develop quantitative methods for studying the vaginal flora and the flora of tampons obtained during menstruation and (ii) to determine whether there were differences between the microflora of the tampon and that of the vaginal vault. Tampon and swab samples were obtained at various times from eight young healthy volunteers for 8 to 10 menstrual cycles. Samples consisted of swabs from women wearing menstrual pads compared with swab and tampon samples taken at various times during the menstrual cycle. Samples were analyzed for total facultative and anaerobic bacterial counts, and the six dominant bacterial species in each culture were identified. Statistical evaluation of the results indicates that total bacterial counts decreased during menstruation and that swab and tampon samples yielded similar total counts per unit weight of sample. The numbers of bacteria in tampons tended to be lower than in swabs taken at the same time. Overall, during menstruation, the concentrations of lactobacilli declined, but otherwise there was little difference among the species found during menstruation compared with those found in intermenstrual samples. Cotton tampons had little discernible effect on the microbial flora.

Adult↗
PubMed1985

Effects of aspirin and alcohol on platelet thromboxane synthesis and vascular prostacyclin synthesis.

We have studied interactions between aspirin and alcohol in vitro with regard to their effects on platelet thromboxane synthesis and vascular prostacyclin synthesis. Alcohol did not affect the inhibition by aspirin of platelet thromboxane synthesis. However, low concentrations of alcohol (0.05-0.15%, v/v) reversed the inhibition by aspirin of vascular prostacyclin synthesis. Since the effects on prostacyclin and thromboxane synthesis would favour bleeding rather than haemostasis, the observations reported herein may explain previous reports of a potentiation by alcohol of the aspirin-induced increase in bleeding time.

Aspirin↗