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K Hanson

Publications and source records attributed to K Hanson.

At least 37 records · Page 2Linked to original sources
PubMed1998

Private health care provision in developing countries: a preliminary analysis of levels and composition.

While the importance of the private sector in providing health services in developing countries is now widely acknowledged, the paucity of data on numbers and types of providers has prevented systematic cross-country comparisons. Using available published and unpublished sources, we have assembled data on the number of public and private health care providers for approximately 40 countries. This paper presents some results of the analysis of this database, looking particularly at the determinants of the size and structure of the private health sector. We consider two different types of dependent variable: the absolute number of private providers (measured here as physicians and hospital beds), and the public-private composition of provision. We examine the relationship between these variables and income and other socioeconomic characteristics, at the national level. We find that while income level is related to the absolute size of the private sector, the public-private mix does not seem to be related to income. After controlling for income, certain socioeconomic characteristics, such as education, population density, and health status are associated with the size of the private sector, though no causal relationship is posited. Further analysis will require more complete data about the size of the private sector, including the extent of dual practice by government-employed physicians. A richer story of the determinants of private sector growth would incorporate more information about the institutional structure of health systems, including provider payment mechanisms, the level and quality of public services, the regulatory structure, and labour and capital market characteristics. Finally, a normative analysis of the size and growth of the private sector will require a better understanding of its impact on key social welfare outcomes.

Delivery of Health Care↗
PubMed1997

Calmodulin-stimulated cyclic nucleotide phosphodiesterase (PDE1C) is induced in human arterial smooth muscle cells of the synthetic, proliferative phenotype.

The diversity among cyclic nucleotide phosphodiesterases provides multiple mechanisms for regulation of cAMP and cGMP in the cardiovascular system. Here we report that a calmodulin-stimulated phosphodiesterase (PDE1C) is highly expressed in proliferating human arterial smooth muscle cells (SMCs) in primary culture, but not in the quiescent SMCs of intact human aorta. High levels of PDE1C were found in primary cultures of SMCs derived from explants of human newborn and adult aortas, and in SMCs cultured from severe atherosclerotic lesions. PDE1C was the major cAMP hydrolytic activity in these SMCs. PDE expression patterns in primary SMC cultures from monkey and rat aortas were different from those from human cells. In monkey, high expression of PDE1B was found, whereas PDE1C was not detected. In rat SMCs, PDE1A was the only detectable calmodulin-stimulated PDE. These findings suggest that many of the commonly used animal species may not provide good models for studying the roles of PDEs in proliferation of human SMCs. More importantly, the observation that PDE1C is induced only in proliferating SMCs suggests that it may be both an indicator of proliferation and a possible target for treatment of atherosclerosis or restenosis after angioplasty, conditions in which proliferation of arterial SMCs is negatively modulated by cyclic nucleotides.

3',5'-Cyclic-AMP Phosphodiesterases↗
PubMed1997

Cloning and origin of the two forms of chicken vitamin D receptor.

The cDNA for the chicken vitamin D receptor (VDR) has been cloned in full length by screening cDNA libraries from chicken intestine and chicken kidney. The chicken kidney cDNA library constructed by both oligo(dT) and random primer methods yielded several full-length clones. These contained a 66-bp additional coding sequence at the 5' end in comparison to the cDNAs of human, rat, and mouse VDR. The Japanese quail VDR cDNA was also cloned in full length. We found that the 5' coding sequence reported previously had been artifactually inverted. Both chicken and quail cDNAs have three conserved ATG sites for translation initiation with the 3' one corresponding to the only ATG site found in the mammalian cDNAs. Northern blot analysis showed that the VDR gene is expressed as a single 2.69-kb transcript in chicken intestine and kidney. An analysis of the avian multiple ATG sites revealed that the first ATG is in a suboptimal context of TCCATGT, while the second ATG is in AGC-ATGG, matching the optimal context: R-3NNATGG+4. As a result, the two forms of chicken VDR (cVDR) (form A, 60.3 kDa; form B, 58.6 kDa) likely arise from the first and second ATG sites of a single mRNA during translation. Mutational analysis confirmed this belief. The wild-type construct starting from the first ATG site with its original context was subcloned into pCMV5 expression vector and expressed in COS-1 cells. Two receptor proteins, exactly comigrating with the form A and form B cVDRs isolated from chicken intestine, were detected by immunoblotting. Point mutations optimizing the first ATG context led to exclusive production of form A, while knocking out the first ATG site resulted in the sole generation of form B. Form A translated from the first ATG site has 451 amino acids, and form B from the second ATG has 437 amino acids. Comparison between avian and mammalian VDRs indicated that VDR is essentially conserved in DNA binding and ligand binding domains. The significant difference especially at the N-terminus demonstrates divergence of this receptor during evolution of these species.

Amino Acid Sequence↗
PubMed1997

Disability-adjusted life years: a critical review.

The disability-adjusted life year (DALY) has emerged in the international health policy lexicon as a new measure of the 'burden of disease'. We argue that the conceptual and technical basis for DALYs is flawed, and its assumptions and value judgements are open to serious question. In particular, the implications of age-weighting and discounting are found to be unacceptable. Moreover, the proponents of DALYs do not distinguish between the exercises of measuring the burden of disease and of allocating resources. But the appropriate information sets for the two exercises are quite different. Allocating resources by aggregate DALY-minimization is shown to be inequitable.

Age Factors↗
PubMed1997

Are two interventions worse than none? Joint primary and secondary prevention of eating disorders in college females.

Prevention programs for eating disorders attempt to simultaneously prevent new cases from arising (primary prevention) and encourage students who already have symptoms to seek early treatment (secondary prevention), even though ideal strategies for these 2 types of prevention may be incompatible with each other. In the present study, an eating disorder prevention program was evaluated in a simple of female college freshmen. In the intervention, classmates who had recovered from eating disorders described their experiences and provided information about eating disorders. At follow-up, intervention participants had slightly more symptoms of eating disorders than did controls. The program may have been ineffective in preventing eating disorders because by reducing the stigma of these disorders (to encourage students with problems to seek help), the program may have inadvertently normalized them.

Adaptation, Psychological↗
PubMed1997

Attenuation of phytochrome A and B signaling pathways by the Arabidopsis circadian clock.

In higher plants, environmental cues such as light signals are integrated with circadian clock signals to control precisely the daily rhythms observed for many biological functions. We have used a fusion of the promoter of a chlorophyll a/b binding protein gene, CAB2, with firefly luciferase (cab2::luc) to monitor the detailed kinetics of transcription in response to photoreceptor activation in Arabidopsis. Using this marker in phototransduction and circadian-dysfunctional mutants, we studied how signals from phytochrome and the circadian clock are integrated for the regulation of CAB2 transcription. Results from these mutant studies demonstrate that similar expression features, namely, the acute and circadian responses, are present in both etiolated and green seedlings and that the acute and circadian responses are genetically separable. We also demonstrate that persistent Pfr signaling occurs in red light-pulsed etiolated seedlings, which suggests that the circadian clock antagonizes Pfr-mediated signal transduction. Based on these genetic studies, we propose a model for the regulation of CAB2 transcription in which individual photoreceptors and phototransduction components have been assigned to specific pathways for the regulation of discrete kinetic components of the CAB2 expression pattern.

Arabidopsis↗
PubMed1996

Inhibition of cyclic 3'-5'-guanosine monophosphate-specific phosphodiesterase selectively vasodilates the pulmonary circulation in chronically hypoxic rats.

While it is known that nitric oxide (NO) is an important modulator of tone in the hypertensive pulmonary circulation, the roles of cyclic 3'-5'-guanosine monophosphate (cGMP) and cGMP-phosphodiesterase (PDE) are uncertain. We found that isolated lung perfusate levels of cGMP were over ninefold elevated in hypertensive vs. normotensive control rats. 98-100% of lung cGMP hydrolytic activity was cGMP-specific PDE5, with no significant decrease in PDE activity in hypertensive lungs, suggesting that the elevation in cGMP was due to accelerated production rather than reduced degradation. In pulmonary hypertensive rat lungs, in vitro, cGMP-PDE inhibition by E4021[1-(6-chloro-4-(3,4-methylbenzyl) amino-quinazolin-2-yl)piperdine-4-carboxylate], increased perfusate cGMP threefold, reduced hypoxic vasoconstriction by 58 +/- 2%, and reduced baseline pulmonary artery pressure by 37 +/- 5%. In conscious, pulmonary hypertensive rats, intravenous administration of E4021 reduced hypoxic vasoconstriction by 68 +/- 8%, pulmonary artery pressure by 12.6 +/- 3.7% and total pulmonary resistance by 13.1 +/- 6.4%, with no significant effect on cardiac output, systemic pressure, and resistance. Comparison of E4021 to inhaled nitric oxide demonstrated that cGMP-PDE inhibition was as selective and as effective as inhaled NO.

3',5'-Cyclic-GMP Phosphodiesterases↗
PubMed1996

"Doin' politics": linking policy and politics in nursing.

Policies affecting nursing are set within the larger environment of the health policy sector. That sector is characterized by increasing size, complexity, and goal displacement. All three characteristics have served to expand the resource base for this sector despite fiscal constraints on such growth. The environment of policy making shapes both the substance of policy change and the strategies for political adoption. Without understanding the dynamics of the policy environment, efforts by nursing leaders to enhance their growing political sophistication and to articulate nursing interests with maximum effectiveness will be compromised.

Decision Making, Organizational↗
PubMed1995

Identification of the porcine intestinal accessory factor that enables DNA sequence recognition by vitamin D receptor.

The nuclear accessory protein in porcine intestinal nuclear extracts that activates the binding of the vitamin D receptor to its vitamin D response elements has been highly purified. It contains a protein that binds 9-cis-[3H]retinoic acid, was detected on immunoblots with an anti-retinoid X receptor (RXR) peptide antibody, and supports the binding of retinoic acid receptor gamma to the retinoic acid receptor beta gene response element. Most important, the two specific complexes formed by porcine nuclear extract with the vitamin D response elements from either the osteocalcin gene or the rat 24-hydroxylase gene are shifted to a larger complex by both an anti-vitamin D receptor antibody and an anti-RXR antibody, leaving no doubt that in vivo the nuclear accessory factor for the vitamin D receptor in the intestine is an RXR protein.

Animals↗
PubMed1995

The impact of infectious diseases on the health of U.S. troops deployed to the Persian Gulf during operations Desert Shield and Desert Storm.

An assessment was conducted of the impact of infectious diseases on the 697,000 U.S. troops deployed to the Persian Gulf during 1990-1991 in Operations Desert Shield and Desert Storm. The incidence of nonbattle injuries, including infectious diseases, during this conflict was lower than during previous wars involving U.S. military personnel. The major reported causes of morbidity were generally mild cases of acute diarrheal and upper respiratory disease. The most unexpected outcome was the lack of arboviral infections, particularly sandfly fever, and the occurrence among U.S. troops of 12 cases of visceral leishmaniasis due to Leishmania tropica. The fact that infectious diseases were not a major cause of lost manpower, in sharp contrast to the experience among military personnel in World War II, can be attributed to a combination of factors: the presence of a comprehensive infrastructure of medical care, extensive preventive medicine efforts, and several fortuitous circumstances. Beneficial conditions that may not be present in future conflicts in this region include isolation of most combat troops to barren desert locations during the cooler, winter months, which provided the least favorable conditions for transmission of arthropod-borne diseases.

Animals↗
PubMed1994

Methodological issues in the administration of multiple doses of smoked cocaine-base in humans.

Many methodological issues exist in human laboratory research with smoked cocaine-base that include safety, precision of dose delivery of smoked cocaine, and the lack of an adequate placebo. All of these issues are particularly apparent with studies involving multiple doses of cocaine. Addressing these concerns is important in conducting parametric studies that require examining dose-response effects. The purposes of this study were to determine: 1) the safest interval between doses to deliver smoked cocaine; 2) the accuracy or reproducibility of administering precise and multiple doses of cocaine; 3) the potential for using a control dose of cocaine; and 4) the influence of multiple doses on these parameters. Six black males were given 10 doses of either 5 or 35 mg of cocaine-base at 15-, 30-, and 45-min intervals. The dependent measures included physiological, subjective, and performance responses. These measures were taken prior to dosing and at specific time intervals after each dose of smoked cocaine. The results showed: 1) dosing at 30-min intervals allowed sufficient time for recovery of blood pressure and heart rate to permit up to 10 doses to be safely administered; 2) reproducible blood cocaine levels were obtained with repeated dosing using a heated wire-coil device; 3) significant differences were observed between the 5- and 35-mg dose with 5 mg being a low enough dose to produce minimal effects; 4) acute tolerance was evidenced with multiple doses of cocaine for most of the measures; and 5) considerable between- and within-subject variability was observed in the pattern of responses to cocaine.

Administration, Inhalation↗
PubMed1994

Transition to retirement: gender differences.

The present investigation consisted of two studies which attempted: 1) to assess the replicability of the investigation by Wapner and Hornstein [1] and Hornstein and Wapner [2,3] that uncovered four distinct modes of experiencing the transition to retirement, and 2) to advance that work by focusing on gender differences. The preliminary study, based on analyses of twenty-four case studies reported by Wapner and Hornstein suggested it would be profitable to study gender differences in a more systematic manner [1]. Toward this end, the major study involved construction of four appropriate instruments which were administered to ninety-four (48 women, 46 men) recent retirees. The four retirement categories (I. Transition to Old Age; II. New Beginning; III. Continuation; IV. Imposed Disruption) described in those investigations was replicated. Moreover, striking gender differences emerged. Theoretical and practical implications of the study were explored.

Adaptation, Psychological↗
PubMed1993

Evidence for unusual stability of ADP-ribosyl linkage to membrane proteins of a murine leukemic cell line.

A set of membrane proteins from murine myelomonocytic leukemia cell line WEHI-3BD+ was found to be ADP-ribosylated. Both this ADP-ribosylation reaction and granulocytic differentiation in response to recombinant G-CSF were inhibited approximately 50% by 2 mM benzamide, suggesting a correlation between these two processes. The stability of the ADP-ribosyl linkage was examined under a series of chemical release conditions and was found to resemble none of the known ADP-ribosyl-amino acid linkages. This chemical modification may represent a new class of mono(ADP-ribosyl) modifications of proteins.

Adenosine Diphosphate Ribose↗
PubMed1993

Ca2+ and endonuclease activation in radiation-induced lymphoid cell death.

Exposure of lymphoid cells to X-irradiation caused an increase in cytosolic Ca2+ ([Ca2+]i) in rat thymocytes but not in rat splenocytes. The Ca2+ elevation in rat thymocytes was transitory and by 2 h postirradiation, when the chromatin degradation began to be appreciable, the [Ca2+]i had returned to control level. Inhibitors of RNA and protein syntheses prevented the radiation-induced [Ca2+]i rise in thymocytes. Pretreatment of both cell types with Ca2+ chelators also prevented DNA fragmentation, chromatin condensation, and cell death caused by X-irradiation. These data suggest that Ca2+ plays an important role in the perpetuation of apoptosis in both thymocytes and splenocytes although a Ca2+ elevation, which may serve as a signal in thymocytes, does not appear to be required to initiate radiation-induced DNA fragmentation in splenocytes.

Animals↗