Towards π-wires on a semiconductor surface: Benzyne on Si(001).

Towards the goal of covalently bound molecular wires on silicon, the adsorption of benzyne on Si(001) was studied by means of scanning tunneling microscopy (STM), X-ray photoelectron spectroscopy (XPS), ultraviolet photoelectron spectroscopy (UPS), and density functional calculations (DFT). The benzyne molecule is found to adsorb preferentially via the strained triple bond on one dimer of the Si(001) surface which results in an intact π system covalently bound to the surface. With increasing coverage, the molecules primarily adsorb along the dimer rows; on stepped surfaces, these molecular wires are all oriented in the same direction.

Plant-based chimeric HPV-virus-like particles bearing amyloid-ß epitopes elicit antibodies able to recognize amyloid plaques in APP-tg mouse and Alzheimer's disease brains.

The main amyloid-beta (Aß) variants detected in the human brain are full-length Aß1-40 and Aß1-42 peptides; however, a significant proportion of AD brain Aß consists also of N-terminal truncated/modified species. The majority of the previous immunotherapeutic strategies targeted the N-terminal immunodominant epitope of the full-length Aß; however, most of the pathological N-truncated forms of Aß lack this critical B cell epitope. Recently, virus-like particles (VLPs), self-assembled structures with highly ordered repetitive patterns on their surface and capable of inducing robust immune responses, were applied as a promising platform for various antigen expressions. In this study, we expressed in plants two chimeric HPV16 L1 capsid proteins obtained by introduction of the ß-amyloid 11-28 epitope (Aß 11-28) into the h4 helix or into the coil regions of the L1 protein. The Aß 11-28 epitope was chosen because it is present in the full-length Aß 1-42 as well as in the truncated/modified amyloid peptide species. After expression, we assembled the chimerical L1/Aß 11-28 into a VLP in which the Aß 11-28 epitope is exposed at very high density (360 times) on the surface of the VLP. The chimeric VLPs elicited in mice Aß-specific antibodies binding to ß-amyloid plaques in APP-tg mouse and AD brains. Our study is the first to demonstrate a successful production in plants and immunogenic properties in mice of chimeric HPV16 L1 VLPs bearing Aß epitope that may be of potential relevance for the development of multivalent vaccines for a multifactorial disease such as AD.

Multi-Phase Solvation Model for Biological Membranes: Molecular Action Mechanism of Amphotericin B.

Amphotericin B (AmB) is still the most effective drug for the treatment of systemic fungal infections in humans. Despite significant theoretical and experimental efforts trying to understand its molecular mechanism of action, the answer has remained elusive. In this work, we present a computational methodology to test the current membrane related hypotheses, namely, transmembrane ion channel, adsorption, and sterol sponge. We use a thermodynamic approach in which we represent the membrane by a multiphase solvation model with atomic detail (MMPSM) and calculate the free energy of transferring the drug between phases with different dielectric properties. Furthermore, we compare AmB to a chemical analogue with increased safety, an l-histidine methyl ester of AmB. Our findings reveal that both drugs dimerize in all solvents studied here. Also, it is energetically unfavorable for the drugs to penetrate into the hydrophobic core of the membrane, unless their concentration is high. Finally, it is thermodynamically possible that the sterols migrate from the membrane into a drug droplet adsorbed at the surface of the bilayer. In light of our results, several effects could take place in the complex antibiotic process. We suggest a molecular mechanism that connects all three hypotheses through a drug concentration dependence and propose that the drug promotes the formation of membrane toroidal pores. Because MMPSM is of general interest, we made it available at http://tripplab.com/tools/mmpsm .

Modeling rare species distribution at the edge: the case for the vulnerable endemic Pyrenean desman in France.

The endemic Pyrenean Desman (Galemys pyrenaicus) is an elusive, rare, and vulnerable species declining over its entire and narrow range (Spain, Portugal, France, and Andorra). The principal set of conservation measures in France is a 5-years National Action Plan based on 25 conservation actions. Priority is given to update its present distribution and develop tools for predictive distribution models. We aim at building the first species distribution model and map for the northern edge of the range of the Desman and confronting the outputs of the model to target conservation efforts in the context of environmental change. Contrasting to former comparable studies, we derive a simpler model emphasizing the importance of factors linked to precipitation and not to the temperature. If temperature is one of the climate change key factors, depicted shrinkage in Desman distribution could be lower or null at the northern (French) edge suggesting thus a major role for this northern population in terms of conservation of the species. Finally, we question the applied issue of temporal and spatial transferability for such environmental favourability models when it is made at the edge of the distribution range.

META060 inhibits multiple kinases in the NF-kappaB pathway and suppresses LPS--mediated inflammation in vitro and ex vivo.

OBJECTIVE: We investigated whether a novel candidate META060 targeted the inflammatory signal transduction without affecting constitutive COX-2 enzymatic activity in lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophages. We also investigated its bioavailability in humans and its anti-inflammatory effect ex vivo. METHODS: We measured prostaglandin E(2), nitric oxide, TNFalpha and IL-6 by ELISA, COX-2 protein by Western blot, NF-kappaB nuclear binding by electrophoretic mobility shift assays, and NF-kappaB activation by luciferase assay. Kinase inhibitions were measured by cell-free assays. Bioavailability was tested in 4 human subjects consuming 940 mg META060. LPS-activated TNFalpha and IL-6 were measured in peripheral blood mononuclear cells (PBMC) isolated from 1 subject up to 6 hours post administration. RESULTS: META060 dose-dependently inhibited prostaglandin E(2) and nitric oxide formation, COX-2 abundance, and NF-kappaB activation. In cell-free assays, META060 inhibited multiple kinases in the NF-kappaB signaling pathway, including BTK, PI3K, and GSK3. META060 was detected in the plasma of the subjects; isolated PBMC were resistant to LPS-stimulated TNFalpha and IL-6 production. CONCLUSION: Without inhibiting COX-2 enzyme, META060 reduces the inflammation by inhibiting multiple kinases involved in NF-kappaB pathway, and may have potential as a safe anti-inflammatory therapeutic.

Gastric mucosal cell model for estimating relative gastrointestinal toxicity of non-steroidal anti-inflammatory drugs.

The study objective was to characterize the AGS human gastric mucosal cell line as a model for estimating gastrointestinal toxicity of COX-inhibiting compounds. Rofecoxib, celecoxib, nimesulide, ibuprofen, indomethacin, aspirin, salicylic acid, naproxen and acetaminophen were tested for inhibition of COX-2-mediated prostaglandin E2 synthesis in A549 and AGS cells. The IC50 ratio AGS/A549 was calculated as an estimate of the therapeutic index (TI) for gastrointestinal toxicity. Calculated IC50 values of non-steroidal anti-inflammatory drugs (NSAIDs) in A549 cells were in excellent agreement with published values (r = 0.996; P < 0.005). Calcium ionophore induction of arachidonic acid release in AGS cells provided TI similar to those using platelets and A549 cells (r = 0.918; P < 0.01). The AGS/A549 model exhibited lower TI than the platelet/A549 model. Spearman ranking correlated clinical NSAID gastropathy with lower AGS TI values. The AGS cell line has excellent potential to serve as a model for assessing the gastrointestinal effects of COX-inhibiting compounds.

Fabrication of single-walled carbon-nanotube-based pressure sensors.

We report on the fabrication and characterization of bulk micromachined pressure sensors based on individual single-walled carbon nanotubes (SWNTs) as the active electromechanical transducer elements. The electromechanical sensor device consists of an individual electrically connected SWNT adsorbed on top of a 100-nm-thick atomic layer deposited (ALD) circular alumina (Al(2)O(3)) membrane with a radius in the range of 50-100 microm. A white light interferometer (WLI) was used to measure the deflection of the membrane due to differential pressure, and the mechanical properties of the device were characterized by bulge testing. Finally, we performed the first electromechanical measurements on strained metallic SWNTs adhering to a membrane and found a piezoresistive gauge factor of approximately 210 for metallic SWNTs.

Psychosocial correlates of sun-protective practices of preschool staff toward their students.

The skin cancer rate in the US has been increasing faster than that for other cancers. Most skin cancers are related to sun exposure and the majority of exposure occurs before adulthood. Thus, children are an important target group to study and preschools can be useful avenues for delivering sun-protection messages. The current study examines the behaviors of preschool staff in protecting students from sun exposure and investigates factors related to sun-protective practice. Preschool staff (n = 245) were surveyed about their sun-protective practices toward students as the cross-sectional baseline measurement for a larger project. The primary aim of this study was to investigate correlates of staff's sun-protective behavior toward students. A theoretical model of psychosocial constructs that combined components of the Theory of Planned Behavior and Social Cognitive Theory was evaluated using structural equation modeling. Self-efficacy and perceived norms were the strongest correlates of behavior. A hypothesized link between expectancy and behavior was not supported. The roles of self-efficacy and perceived norms in the preschool context are discussed as they relate to staffs behavior.

The influence of level of feeding on growth and serum insulin-like growth factor I and insulin-like growth factor-binding proteins in growing beef cattle supplemented with somatotropin.

The objective of this study was to determine the effects of level of feeding on growth, feed efficiency (gain:feed; G:F), body composition (BC), and serum concentrations of somatotropin (ST), IGF-I, and IGF-binding proteins (BP) in growing beef cattle supplemented with bovine (b) ST. In each of two consecutive years, 40 growing beef cattle were blocked by weight (average BW: yr 1 = 316 kg, yr 2 = 305 kg) and used in a 2 x 2 factorial arrangement with main effects of bST (0 or 33 microg x kg BW(-1) x d(-1)) and level of feed intake (ad libitum [AL] or 0.75 AL). Relative to uninjected cattle, treatment with bST increased ADG 9.6% (1.14 vs 1.25 kg/d; P < 0.05) and increased G:F 8.1% (12.3 vs 13.3 gain [g]:feed [kg]; P < 0.05), whereas ADG in AL animals was 39% greater than that in 0.75 AL animals (1.39 vs 1.00 kg/d; P < 0.05). There was a tendency (P = 0.10) for a bST x level of feeding interaction, such that the increase in ADG with bST was greater in AL cattle than in 0.75 AL cattle (10.6 vs 7.8%; P = 0.10). Serum concentrations of ST were greater in 0.75 AL cattle than in AL cattle (13.0 vs 8.6 ng/mL; P < 0.05) and in bST-treated cattle than in uninjected cattle (16.3 vs 5.2 ng/mL; P < 0.05). Due to a bST x level of feeding interaction (P < 0.01), the magnitude of the increase in serum ST to exogenous bST was greater (P < 0.01) in 0.75 AL cattle than in AL cattle. Relative to uninjected cattle, treatment with bST increased (P < 0.05) serum concentrations of IGF-I and IGFBP-3 and reduced (P < 0.05) concentrations of IGFBP-2. Similarly, AL cattle had greater (P < 0.05) serum concentrations of IGF-I and IGFBP-3 and reduced (P < 0.05) IGFBP-2 compared with 0.75 AL cattle. In summary, treatment with bST increased growth rate and G:F and stimulated serum IGF-I and IGFBP-3 while reducing IGFBP-2. Feeding at 0.75 ad libitum intake reduced the magnitude of response for each of these variables. Thus, limit-feeding may reduce the effect of exogenous bST on growth rate by blunting bST-induced increases in IGF-I and IGFBP-3 and bST-induced decreases in IGFBP-2.

Changes in health care providers' knowledge, attitudes, beliefs, and behaviors regarding domestic violence, following a multifaceted intervention.

PURPOSE: To improve domestic violence (DV) identification, management, and referral in a not-for-profit rural health network, training for health care professionals was implemented using a train-the-trainer approach, two one-hour training sessions, and dissemination of a clinical protocol. The multifaceted approach also involved modifications of emergency department medical records, distribution of office enablers, and a local public health campaign. The authors measured the effectiveness of this campaign. METHODS: After implementation of a multifaceted training and public awareness campaign, a questionnaire designed by the Centers for Disease Control to measure knowledge, attitudes, beliefs, and intended behaviors (KABB) of health care providers relative to DV was administered to 380 health care professionals in the fall of 1997, with a follow-up survey completed after the intervention in the fall of 1999. RESULTS: The response rates for the pre- and post-intervention surveys were 67% (n = 380) and 56% (n = 273), respectively. Two scales were correlated in the base-line survey: self-efficacy (related to DV response) and familiarity with referral resources. Reporting of victim identification in the preceding year increased from 36% to 39%. Those with training were more likely to have identified a victim within the year (OR = 2.86; 95% CI, 1.73-4.74). Among the 232 respondents with complete data, multiple analysis of variance demonstrated statistically significant overall improvement across all scales. Nine of the 13 KABB scales revealed significant increases from pre- to posttest and included: screening, workplace resources, making referrals, provider self-efficacy, victim autonomy, victim understanding, legal requirements, staff preparation, and too busy/can't help. CONCLUSION: A comprehensive training program for health care providers can increase their self-efficacy in responding to DV victims.

Impact of a rural domestic violence prevention campaign.

Domestic violence is a prevalent health problem that in rural areas is further complicated by limited services, social isolation and the lack of privacy. Little is known about the impact of public health education on awareness, attitudes and behavior of the general public regarding domestic violence. This study sought to measure change in societal attitudes and behavioral intention in response to a seven-month public health education campaign targeting domestic violence in a rural county. From October 1998 to April 1999, the campaign used radio advertisements, posters, mailings to libraries and clergy, printed media articles, printed advertisements and health facility modifications. A random-digit-dialing telephone survey was used to evaluate attitudinal and behavioral changes in the intervention and comparison counties before and after the campaign. The response rates for the pre- (n =378) and postcampaign (n=633) surveys were 73 percent and 65 percent, respectively. Statistically significant increases in slogan and advertising recognition occurred in the intervention county (P=0.03), particularly among men recalling the campaign slogan (P=0.006). In a vignette regarding actions to be taken if the neighbor next door was abusing a partner, significant increases occurred in the intervention county in the percentage of respondents who thought that most people would talk to the victim (P=0.04), consult with friends (P=0.002) or talk to a doctor (P=0.004). Domestic violence agency hotline calls in the intervention county doubled following the campaign. Local public health education campaigns in a rural setting may be a valuable adjunct to national efforts, especially in reaching men.

Influence of somatotropin and nutrition on bovine oocyte retrieval and in vitro development.

The objective of this study was to determine the effects of supplemental bovine somatotropin (bST) and limit feeding on follicular growth and oocyte competence in yearling beef heifers. Sixteen growing heifers (424+/-4 kg) were randomly assigned to 1 of 4 treatments in a 2 x 2 factorial arrangement, with main effects of bST (0 or 33 microg/kg BW/d) and feeding regimen (ad libitum or 0.75 ad libitum intake). Animals were treated for 100 d prior to follicular aspiration, and treatments continued for the 42-d period that follicles were aspirated. Follicles were observed ultrasonically then aspirated, and recovered oocytes were matured, fertilized and developed in vitro. The number of follicles observed ultrasonically was greater with bST treatment (P<0.01) but was unchanged by plane of nutrition. The number and quality of recovered oocytes were similar among treatments, as was the number of oocytes resulting in blastocyst formation.

Sun Protection is Fun! A skin cancer prevention program for preschools.

Children and their caregivers are prime candidates for intervention to curb the rising incidence of skin cancer in the United States. Preschools provide a unique opportunity to influence the sun protection practices of parents and teachers on behalf of young children. Sun Protection is Fun!, a comprehensive skin cancer prevention program developed by The University of Texas M. D. Anderson Cancer Center in collaboration with The University of Texas-Houston Health Science Center School of Public Health, was introduced to preschools in the greater Houston area. The program's intervention methods are grounded in Social Cognitive Theory and emphasize symbolic modeling, vicarious learning, enactive mastery experiences, and persuasion. Program components include a curriculum and teacher's guide, videos, newsletters, handbooks, staff development, group meetings designed to encourage schoolwide changes to support the program, and sunscreen. The intervention map, including objectives for program development, implementation, and evaluation, is discussed.

Developmental competence of juvenile calf oocytes in vitro and in vivo: influence of donor animal variation and repeated gonadotropin stimulation.

Juvenile calf oocytes represent an untapped source of germ plasm for reproduction. Reports on the developmental competence of calf oocytes have been controversial. In this research, oocytes were recovered after gonadotropin stimulation from Holstein calves (N = 10) at 2-3 mo of age (2-mo cycle) and again at 4-5 mo of age (4-mo cycle). The in vitro developmental competence was measured, and prestimulation follicle numbers (for 2-mo cycle) and poststimulation follicle numbers (both cycles) were obtained. The number of antral follicles doubled after stimulation (23.4 +/- 6.1 vs. 55.1 +/- 16.1) for the 2-mo cycle and for the 4-mo cycle (47.4 +/- 12.4). The number of follicles observed prior to stimulation in the 2-mo cycle was found to be highly correlated with the poststimulation oocyte recovery for both collection cycles (r = 0.95, 2-mo cycle; r = 0.81, 4-mo cycle). The majority (90-96%) of recovered oocytes were found to be usable for in vitro maturation and fertilization; of these, 41-42% cleaved and 10-11% developed to morulae or blastocysts. Eighty-four in vitro-produced embryos were transferred to synchronized recipients and resulted in 11 pregnancies, leading to 7 live (4 males, 3 females) and 2 dead (one male, one female) calves at full term. No significant differences were observed between the 2-mo and 4-mo collection cycles; however, 73% of the total pregnancies resulted from the 2-mo cycle. All pregnancies resulted from embryos of high-responding donors. The high correlation between the number of follicles prior to stimulation and the poststimulation response suggests the possibility of screening calves prior to stimulation for routine embryo production.

Clinical implications for four drugs of the DSM-IV distinction between substance dependence with and without a physiological component.

OBJECTIVE: The DSM-IV work group asked researchers and clinicians to subtype substance dependent individuals according to the presence or absence of physiological symptoms. A recent report from the Collaborative Study on the Genetics of Alcoholism demonstrated that among alcohol-dependent men and women, a history of tolerance or withdrawal was associated with a more severe clinical course, especially for individuals with histories of alcohol withdrawal. This article evaluates similar distinctions among subjects in the collaborative study who were dependent on marijuana, cocaine, amphetamines, or opiates. METHOD: Structured interviews gathered information from 1,457 individuals with a lifetime diagnosis of marijuana dependence, 1,262 with histories of cocaine dependence, 647 with amphetamine dependence, and 368 subjects with opiate dependence. For each drug, the clinical course was compared for subjects whose dependence included a history of withdrawal (group 1), those dependent on each drug who denied withdrawal but reported tolerance (group 2), and those who denied both tolerance and withdrawal (group 3). RESULTS: The proportion of dependent individuals who denied tolerance or withdrawal (group 3) ranged from 30% for marijuana to 4% for opiates. For each substance, individuals in groups 1 and 2 evidenced more severe substance-related problems and at least a trend for greater intensities of exposure to the drug; those reporting withdrawal (group 1) showed the greatest intensity of problems. CONCLUSIONS: The designation of dependence in the context of tolerance or withdrawal identifies individuals with more severe clinical histories. These results support the importance of the designation of a physiological component to dependence, especially for people who have experienced a withdrawal syndrome.

Methionine and somatotropin supplementation in growing beef cattle.

This objective of this study was to determine the effects of supplemental bovine somatotropin and supplemental ruminally protected methionine (Met) on ADG, feed efficiency (FE), body composition (BC), and serum concentrations of Met, ST, IGF-I, and progesterone in growing beef cattle. Two experiments were conducted. In one experiment, 24 growing beef cattle (6 steers and 18 heifers, 410 +/- 2 kg) were divided into two treatment groups, either controls or Met-treated animals. In a second experiment, 32 heifers and 8 steers (311 +/- 2 kg) were used in a completely randomized design experiment (four treatments; two pens/treatment). Treatments were arranged as a 2 x 2 factorial, with main effects of ST (0 or 33 microg/kg BW per day) and Met (0 or 6 g x animal(-1) x d(-1)). Feed efficiency and ADG were not affected by Met. However, ST increased FE and ADG (P < .05). Serum Met concentrations tended (P = .08) to increase with Met administration and remained unchanged by ST administration. Serum ST and IGF-I concentrations were increased (P < .05) by ST administration but unchanged by Met administration. The BC and heifer serum progesterone concentrations were similar across treatments, and no interactions (P > .10) were observed between ST and Met. In summary, ST improved BW gain and FE. Methionine was not the first-limiting AA in the diet fed.

Worksite health and safety climate: scale development and effects of a health promotion intervention.

BACKGROUND: Environmental influences on health and health behavior have an important place in research on worksite health promotion. We tested the validity and internal consistency of a new measure of organizational health and safety climate that was used in a large randomized trial of a worksite cancer prevention program (the Working Well Trial). The resulting scales then were applied to assess intervention effects. METHODS: This study uses data from a subset of 40 worksites in the Working Well Trial. Employees at 20 natural gas pipeline worksite and 20 rural electrical cooperatives completed a cross-sectional questionnaire at baseline and 3-year follow-up. RESULTS: A factor analysis of this self-report instrument produced a two-factor solution. The resulting health and safety climate scales had good internal consistency (Cronbach's alpha = 0.74 and 0.82, respectively) and concurrent validity. The health climate scale was correlated more highly with organizational measures that were indicative of a supportive health climate than those indicating supportive safety climate, while the reverse was true of the safety climate scale. Changes in health climate were associated with the number of smoking and smokeless tobacco programs offered at the worksites at the time of the 3-year follow-up (r = 0.46 and 0.42, respectively). The scales were not correlated with most employee health behaviors. The health climate scores increased at intervention worksites, compared with scores at control worksites (F[1,36] = 7.57, P = 0.009). CONCLUSIONS: The health and safety climate scales developed for this study provide useful instruments for measuring organizational change related to worksite health promotion activities. The Working Well Intervention resulted in a significant improvement in worksite health climate.

Effect of repair strategy on hospital cost for infants with tetralogy of Fallot.

OBJECTIVE: This study compares the total hospital cost (HC) for one-stage versus "two-stage" repair of tetralogy of Fallot (TOF) in infants younger than 1 year of age. SUMMARY BACKGROUND DATA: Total (one-stage) correction of TOF is now being performed with excellent results in infancy. Alternatively, a two-stage approach, with palliation of infants in the first year of life, followed by complete repair at a later time can be used. In some institutions, the two-stage approach is standard practice for infants younger than 1 year of age or is used selectively in patients with an anomalous coronary artery across the right ventricular outflow tract (RVOT), "small pulmonary arteries," multiple congenital anomalies, critical illnesses (CI), which increase the risk of bypass (e.g., sepsis or DIC), or severe hypercyanotic spells (HS) at the time of presentation. The cost implications of these two approaches are unknown. METHODS: The authors reviewed 22 patients younger than 1 year of age who underwent repair of TOF at their institution between 1993 and 1995. Eighteen patients had one-stage (1 degree) repair (mean age, 3.4 +/- 3.1 months; range, 3 days-9 months) and 4 patients were treated by a staged approach with initial palliation (1.6 +/- 0.4 month; range, 1.5-2 months) followed by later repair (14.75 +/- 1.5 months; range, 13-16 months). The reasons for palliation were severe HS at time of presentation (two patients), anomalous coronary artery (one patient) and CI (one patient). In the 18 patients undergoing 1 degree repair, 3 (16.6%) presented with HS, 6 (33.3%) had a transanular repair, and 6 (33.3%) were able to be repaired through an entirely transatrial approach (youngest patient, 1.5 months). The HC (1996 dollars) and hospital length of stay (LOS; days) were evaluated for all patients. The HCs were calculated using transition I, which is a cost accounting system used by our medical center since July 1992. Transition I provides complete data on all direct and indirect hospital-based, nonprofessional costs. RESULTS: There was no mortality in either group. The group undergoing 1 degree repair had an average LOS of 14.5 +/- 11.2 days compared to an average LOS for palliation of 14 +/- 6.4 days. When the palliated group returned for complete repair, the average LOS was 28.8 +/- 25 days, yielding a total LOS for the two-stage strategy of 43 +/- 30.8 days (p = 0.003 compared to 1 degree repair). The HC for 1 degree repair was $32,541 +/- $15,968 compared to $25,737 +/- $1900 for palliation (p = not significant compared to 1 degree repair) and $54,058 +/- $39,395 for subsequent complete repair (p = not significant compared to 1 degree repair) (total two-stage repair HC = $79,795 +/- $40,625; p = 0.001 compared to 1 degree repair). The LOS and HC for the two-stage group combine a total of palliation plus later repair and, as such, reflect two separate hospitalizations and convalescent periods. To eliminate cost outliers, a best-case analysis was performed by eliminating 50% of patients from each group. Using this analysis, the two-stage approach resulted in an average (total) LOS of 16.5 +/- 2.1 days compared to 8.5 +/- 1.4 days for the 1 degree group. Total cost for the two-stage strategy in this best-case group was $44,660 +/- $3645 compared to $22,360 +/- $3331 for 1 degree repair (p = 0.00001). CONCLUSIONS: The data from this review show that palliation alone generates HC similar to that from 1 degree infant repair of TOF, and total combined HC and LOS for palliation plus eventual repair of TOF (two-stage approach) are significantly higher than from 1 degree repair. Furthermore, these data do not include additional costs for care delivered between palliation and repair (e.g., outpatient visits, cardiac catheterization, serial echocardiography). Although there may be occasions when a strategy using initial palliation followed by later repair may seem prudent, the cost is clearly higher and use of health care resources greater.

Approaches to the prevention and control of skin cancer.

Skin cancer is the most common and the most preventable form of cancer. Nonmelanoma skin cancers are associated with cumulative exposure to ultraviolet radiation, while melanoma is associated with intense episodes of ultraviolet exposure resulting in sunburns. Numerous risk factors are associated with the development of skin cancer. These include exposure to ultraviolet radiation; phenotypic factors such as skin type, eye and hair color, tendency to burn and tan, and having freckles and moles; a personal or family history of skin cancer; and occupational sun exposure. Primary prevention behaviors include applying SPF 15+ sunscreen 30 minutes before exposure, reapplying SPF 15+ sunscreen every 1 1/2 to 2 hours or after swimming or sweating, dressing in protective clothing, using shade, limiting exposure during peak sun hours, and avoiding artificial sources of ultraviolet radiation such as tanning beds. Secondary prevention behaviors include screening and early detection in combination with education on the primary prevention behaviors. Interventions designed to increase sun protective behaviors have resulted in increased knowledge and attitudes, but limited behavior change. And while skin cancer screenings have shown promising results, few studies have a follow-up component. Future studies should focus on developing effective strategies for making sun protective behaviors routine and determining the effectiveness of skin cancer screening. To inform approaches to the prevention and control of skin cancer, this paper will summarize key primary and secondary preventive behaviors, highlight primary and secondary prevention programs, and identify key unanswered questions in the area of skin cancer prevention and control.