bluuebunny/crossref_metadata_2025 huggingface dataset:
Understanding Factors Associated With Work Loss for Families Caring for CSHCN
Authors: Okumura Megumi J. , Van Cleave Jeanne , Gnanasekaran Sangeeth , Houtrow Amy
Published: November 2009

OBJECTIVE: Parents of children with special health care needs (CSHCN) are at risk for work loss as a result of the complex health needs of their children. Our objective was to determine how child- and family-level factors and the medical home are associated with work loss for these families.

METHODS: We performed secondary data analyses of the National Survey of Children With Special Health Care Needs (NS-CSHCN) 2005–2006. This is a nationally representative sample of CSHCN in the United States. The primary outcome measure was having any family member report work loss to care for a CSHCN. We calculated survey-weighted unadjusted and adjusted odds ratios by using independent variables that included child demographic factors, functional limitation, condition stability, insurance status/type, family income, and criteria of the medical home.

RESULTS: Overall, 23.7% of the parents of CSHCN reported work loss as a result of their child's health care needs. Greater functional limitation and condition instability were associated with increased odds of family work loss. The presence of a medical home in the multivariate model was associated with a 50% reduction in the odds of reported family work loss.

CONCLUSIONS: Approximately 24% of families with CSHCN have experienced work loss to meet the medical needs of their child. Availability of a system of care support, such as the medical home, is associated with lower work loss reported by families. Therefore, improved systems of care for CSHCN may have the potential to optimize work productivity for families.
Household Language Use and Health Care Access, Unmet Need, and Family Impact Among CSHCN
Authors: Yu Stella M. , Singh Gopal K.
Published: November 2009

OBJECTIVES: We examined the association of household language use and access to care among children with special health care needs (CSHCN). From this study we describe the demographics of children and the prevalence of selected access characteristics according to their primary household language and examine the independent effects of household language on health care access, unmet needs, and family impact while controlling for confounding variables.

METHODS: Data from the 2005–2006 National Survey of Children With Special Health Care Needs, a nationally representative telephone survey of 40723 CSHCN, were analyzed. Bivariate and multivariable analyses were used to examine disparities and estimate adjusted odds ratios of health care access, satisfaction, and family-impact measures for CSHCN from non–English-primary-language (NEPL) versus English-primary-language (EPL) households.

RESULTS: Nearly 14% of all US children live in NEPL households. NEPL CSHCN were significantly more likely to be Hispanic or other race, be poor, have less educated parents, and reside in metropolitan areas and larger households and yet were less likely to be on cash assistance from welfare. Logistic regression showed that NEPL CSHCN were twice as likely to lack access to a medical home, a usual source of care, and family-centered care. They were 4 times as likely to lack health insurance, and their family members were also more likely to lack adequate insurance. Family members of NEPL children were almost twice as likely to have to stop employment as a result of their child's condition.

CONCLUSIONS: Although limited by program eligibility contingent on immigrant status and state policies, increased referrals to programs such as the State Children's Health Insurance Program and Medicaid can improve access while utilization can be improved by the availability of interpreters, community health workers, linguistically concordant providers, and outreach education efforts of NEPL parents.
Care Coordination for CSHCN: Associations With Family-Provider Relations and Family/Child Outcomes
Authors: Turchi Renee M. , Berhane Zekarias , Bethell Christina , Pomponio Amber , Antonelli Richard , Minkovitz Cynthia S.
Published: November 2009

OBJECTIVE: To examine the association between receiving adequate care coordination (CC) with family-provider relations and family/child outcomes.

METHODS: We analyzed data from the 2005–2006 National Survey of Children With Special Health Care Needs. Eligible subjects were the 88% of families asked about experience with CC, service use, and communication. Respondents also reported on demographic characteristics, health status, family-provider relations, and family/child outcomes. Weighted, multivariate logistic regression models were constructed to assess independent associations of adequate CC with outcomes.

RESULTS: Among families with children with special health care needs asked about CC, 68.2% reported receiving some type of CC help. Of these, 59.2% reported receiving adequate CC help, and 40.8% reported inadequate CC. Families that reported adequate compared with inadequate CC had increased odds of receiving family-centered care, experiencing partnerships with professionals, and satisfaction with services. They had decreased odds of having problems with referrals for specialty care, missing >6 school days because of illness (previous year), and visiting the emergency department more than twice in the previous 12 months (P < .001). Those who reported adequate compared with inadequate CC had decreased odds of the following: more than $500/y of out-of-pocket expenses, family financial burden, spending more than 4 hours/week coordinating care, and stopping/reducing work hours.

CONCLUSIONS: Parental report of adequate CC was associated with favorable family-provider relations and family/child outcomes. Additional efforts are needed to discern which aspects of CC are most beneficial and for which subgroups of children with special health care needs.
Access to Genetic Counseling for Children With Autism, Down Syndrome, and Intellectual Disabilities
Authors: McGrath Robert J. , Laflamme David J. , Schwartz Amy P. , Stransky Michelle , Moeschler John B.
Published: November 2009

OBJECTIVE: We examined the need for genetic counseling services (GCS) for families of children with autism spectrum disorder (ASD), Down syndrome (DS), and/or mental retardation (MR) and factors that influence the receipt of needed GCS for those children relative to other children with special health care needs (CSHCN).

METHODS: Analysis was conducted on the 2005–2006 National Survey of Children With Special Health Care Needs, a nationally representative sample. Bivariate analyses were conducted by examining need for and receipt of GCS for children with ASD, DS, and/or MR and other CSHCN as well as differences by contextual variables using the health belief model (HBM). Logistic regression analyses were conducted to assess the relative impact of receipt of needed GCS by HBM constructs.

RESULTS: Families of children with diagnoses of ASD, DS, and/or MR perceive significantly higher need for GCS than other CSHCN. The presence of a medical home is the single most important factor in facilitating access to GCS, together with the presence of insurance, particularly private or a combination of private and public insurance. As income and education attainment decrease, barriers to GCS rise.

CONCLUSIONS: This analysis supports strategies for improving linkages between specialty providers and the medical home at which primary care is delivered. Increased effort should be made to attend to those who experience barriers that result from lack of insurance, poverty, low education, or racial or ethnic differences. Health professionals need to collaborate in developing solutions to underinsurance or lack of insurance for CSHCN.
Cost of Universal Influenza Vaccination of Children in Pediatric Practices
Authors: Yoo Byung-Kwang , Szilagyi Peter G. , Schaffer Stanley J. , Humiston Sharon G. , Rand Cynthia M. , Albertin Christina S. , Vincelli Phyllis , Blumkin Aaron K. , Shone Laura P. , Coleman Margaret S.
Published: November 2009

OBJECTIVES: The goals were to estimate nationally representative pediatric practices' costs of providing influenza vaccination during the 2006–2007 season and to simulate the costs pediatric practices might incur when implementing universal influenza vaccination for US children aged 6 months to 18 years.

METHODS: We surveyed a stratified, random sample of New York State pediatric practices (N = 91) to obtain information from physicians and office managers about all practice resources associated with provision of influenza vaccination. We estimated vaccination costs for 2 practice sizes (small and large) and 3 geographic areas (urban, suburban, and rural). We adjusted these data to obtain national estimates of the total practice cost (in 2006 dollars) for providing 1 influenza vaccination to children aged 6 months to 18 years.

RESULTS: Among all respondents, the median total cost per vaccination was $28.62 (interquartile range: $18.67–45.28). The median component costs were as follows: clinical personnel labor costs, $2.01; nonclinical personnel labor costs, $7.96; all other (overhead) costs, $10.43. Vaccine purchase costs averaged $8.22. Smaller practices and urban practices had higher costs than larger or suburban practices. With the assumption of vaccine administration reimbursement for all Vaccines for Children (VFC)-eligible children at the current Medicaid median of $8.40, the financial loss across all US pediatric practices through delivery of VFC vaccines would be $98 million if one third of children received influenza vaccine.

CONCLUSION: The total cost for pediatric practices to provide influenza vaccination is high, varies according to practice characteristics, and exceeds the average VFC reimbursement.
Underinsurance and Adolescent Immunization Delivery in the United States
Authors: Smith Philip J. , Lindley Megan C. , Shefer Abby , Rodewald Lance E.
Published: November 2009

OBJECTIVE: The goal was to explore the association of being underinsured and receiving doses at a health department clinic (HDC) with not receiving all recommended adolescent vaccine doses.

METHODS: A total of 5657 adolescents, 13 to 17 years of age, were sampled in the National Immunization Survey-Teen in 2006–2007.

RESULTS: A total of 63.9% of all adolescents were covered by private health insurance. Among privately insured adolescents, ∼31.3% were underinsured. Compared with fully insured adolescents, underinsured adolescents were more likely to receive doses at an HDC for tetanus-diphtheria toxoids/tetanus toxoids-reduced diphtheria toxoids-acellular pertussis vaccine (25.1% vs 6.2%; P < .05), tetravalent meningococcal conjugate vaccine (11.5% vs 2.5%; P < .05), and quadrivalent human papillomavirus vaccine (16.2% vs 3.4%; P < .05). Also, compared with fully insured adolescents, underinsured adolescents who received doses at an HDC had lower estimated rates of vaccination coverage for tetanus-diphtheria toxoids/tetanus toxoids-reduced diphtheria toxoids-acellular pertussis vaccine (58.5% vs 70.9%; P < .05), tetravalent meningococcal conjugate vaccine (10.8% vs 25.8%; P < .05), and quadrivalent human papillomavirus vaccine (7.8% vs 14.3%; P < .05).

CONCLUSION: Underinsured adolescents who receive doses at an HDC have lower rates of vaccination coverage than do fully insured adolescents.
Role of Health Insurance in Financing Vaccinations for Children and Adolescents in the United States
Authors: Shen Angela K. , Hunsaker John , Gazmararian Julie A. , Lindley Megan C. , Birkhead Guthrie S.
Published: November 2009

OBJECTIVE: The goal was to elicit perspectives of selected health insurance plan medical or quality improvement directors regarding factors related to coverage and reimbursement and perceptions of financing as a barrier to child and adolescent immunization.

METHODS: Medical or quality improvement directors from 20 plans selected by America's Health Insurance Plans were invited to complete an online survey in July 2007. Respondents who agreed to follow-up interviews were invited to participate in telephone interviews conducted by Centers for Disease Control and Prevention staff members in August 2007.

RESULTS: Fifteen plans (representing >67 million enrollees) responded to the online survey. All respondents covered all Advisory Committee on Immunization Practices–recommended child and adolescent vaccines in all or most products. Advisory Committee on Immunization Practices recommendations were the most commonly cited criteria for coverage decisions (86.7%) and coverage modifications (100%). Factors affecting reimbursement that were cited most often were manufacturer's vaccine price (80%) and physician feedback (53.3%). In follow-up interviews with 10 self-selected respondents, manufacturer's price (7 of 10 plans) and physician feedback (4 of 10 plans) were identified as the most-important factors affecting reimbursement. Respondents said that reimbursement delays were most commonly attributable to providers' claim submission errors or patient ineligibility. Some respondents thought that vaccine financing was a barrier (4 of 10 plans) or somewhat a barrier (2 of 10 plans) to providing immunizations; others (4 of 10 plans) did not.

CONCLUSION: Although these data suggest that health insurance coverage for recommended vaccines is high, coverage is not universal across all products offered.
Financing the Delivery of Vaccines to Children and Adolescents: Challenges to the Current System
Authors: Lindley Megan C. , Shen Angela K. , Orenstein Walter A. , Rodewald Lance E. , Birkhead Guthrie S.
Published: November 2009

Recent increases in the number and costs of vaccines routinely recommended for children and adolescents have raised concerns about the ability of the current vaccine financing and delivery systems to maintain access to recommended vaccines without financial barriers. Here we review the current state of US financing for vaccine delivery to children and adolescents and identify challenges that should be addressed to ensure future access to routinely recommended vaccines without financial barriers. Challenges were considered from the perspectives of vaccine providers; state and local governments; insurers, employers, and other health care purchasers; vaccine manufacturers; and consumers.
Physician Refusal to Provide Information or Treatment on the Basis of Claims of Conscience
Authors:   Committee on Bioethics
Published: November 2009

Health care professionals may have moral objections to particular medical interventions. They may refuse to provide or cooperate in the provision of these interventions. Such objections are referred to as conscientious objections. Although it may be difficult to characterize or validate claims of conscience, respecting the individual physician's moral integrity is important. Conflicts arise when claims of conscience impede a patient's access to medical information or care. A physician's conscientious objection to certain interventions or treatments may be constrained in some situations. Physicians have a duty to disclose to prospective patients treatments they refuse to perform. As part of informed consent, physicians also have a duty to inform their patients of all relevant and legally available treatment options, including options to which they object. They have a moral obligation to refer patients to other health care professionals who are willing to provide those services when failing to do so would cause harm to the patient, and they have a duty to treat patients in emergencies when referral would significantly increase the probability of mortality or serious morbidity. Conversely, the health care system should make reasonable accommodations for physicians with conscientious objections.
Survival and Dispersal of Hatchery Triploid Rainbow Trout in an Idaho River
Authors: High Brett , Meyer Kevin A.
Published: November 2009

Hatchery rainbow trout Oncorhynchus mykiss of catchable size (hereafter, “catchables”) are commonly released into streams to improve angler catch and harvest rates, but returns are often less than 50% and the fate of unharvested catchables is largely unknown, especially for sterilized hatchery trout. The survival and dispersal of triploid catchables were investigated using snorkel and telemetry techniques to quantify the persistence and dispersal of catchables stocked three times during the summer of 2006 (June, July, and August) into an Idaho river in which a minimum length regulation precluded harvest. Counts of catchables stocked with T-bar tags (n = 900) and catchables emitting active radio transmitter codes (n = 54) steadily declined throughout the three observation periods. Dispersal of T-bar-tagged catchables 30 d poststocking was generally downstream of the stocking point (median dispersal = 100 m). The median values of the maximum known downstream and upstream dispersal distances for catchables with radio transmitters were 5.0 and 1.2 km from the stocking point, respectively. Only four transmitter-implanted catchables were still alive on November 1, when the study ended. On average, 85% of catchables with radio transmitters were presumed dead at 30 d poststocking (average persistence = 14.3 d). A similar rate of decline was observed for T-bar-tagged catchables. Managers wishing to maximize return-to-creel rates of sterile catchables in lotic systems might do so by limiting stocking events to within 3 weeks of expected needs and limiting the stocking locations to within 1 km of areas frequented by anglers.
Comparative Effects of Rotenone and Antimycin on Macroinvertebrate Diversity in Two Streams in Great Basin National Park, Nevada
Authors: Hamilton Bryan T. , Moore Steve E. , Williams Tod B. , Darby Neal , Vinson Mark R.
Published: November 2009

We used rotenone and antimycin A to eradicate nonnative rainbow trout Oncorhynchus mykiss and brook trout Salvelinus fontinalis as part of a program to reintroduce Bonneville cutthroat trout O. clarkii utah in two streams in Great Basin National Park, Nevada. These treatments followed standard protocols for piscicide application and provided a unique opportunity to compare the effects of the two piscicides on macroinvertebrate diversity over a short spatial and temporal window. Antimycin A had minimal effects on macroinvertebrate diversity. Total species richness and that of Ephemeroptera, Plecoptera, and Trichoptera (EPT); total and EPT density; and Simpson index values were reduced significantly more with rotenone than with antimycin. The Hilsenhoff biotic index increased with rotenone but decreased with antimycin A. Rotenone also had greater effects on species composition. The proportions of EPT taxa, shredders, and filterers were less than expected when rotenone was used, whereas scraper proportions were greater than expected. The proportions with antimycin A did not differ from those expected. No taxa were lost from antimycin A–treated sites, but four taxa were still missing from rotenone-treated sites 1 year posttreatment. Of these four taxa, however, two were collected 3 years posttreatment. We suggest that antimycin A be used rather than rotenone if minimizing the effects on macroinvertebrates is important. Recovery was relatively rapid with both piscicides, however, and if the short-term impacts on macroinvertebrates are not a concern, the use of rotenone may be appropriate.
Influence of the Hyporheic Zone on Supersaturated Gas Exposure to Incubating Chum Salmon
Authors: Arntzen Evan V. , Geist David R. , Murray Katherine J. , Vavrinec John , Dawley Earl M. , Schwartz Dennis E.
Published: November 2009

Hydroelectric dam operation causes total dissolved gas (TDG) to be seasonally elevated in the lower Columbia River, as surface water concentrations approach 120%. Federally protected chum salmon Oncorhynchus keta embryos incubating in nearby spawning areas could be affected if depth-compensated TDG concentrations within the hyporheic zone exceed 103%. The objective of this study was to determine whether TDG of the hyporheic zone in two chum salmon spawning areas—one in a side channel near Ives Island, Washington, and another on the main-stem Columbia River near Multnomah Falls, Oregon—was affected by the elevated TDG of the surface water. Depth-compensated hyporheic TDG did not exceed 103% at the Multnomah Falls site. However, in the Ives Island area, chum salmon redds were exposed to TDG greater than 103% for more than 300 h. In response to river depth fluctuations, TDG varied significantly in the Ives Island area, suggesting increased interaction between the hyporheic zone and surface water at that site. We conclude from this study that the interaction between surface water and the hyporheic zone affects the concentration of TDG within the hyporheic zone directly via physical mixing and indirectly by altering water chemistry and thus dissolved gas solubility. Consideration of these interactions is important when estimating TDG exposure within egg pocket environments and will enable resource managers to optimize recovery strategies.
Effects of Fin-Clipping on the Foraging Behavior and Growth of Age-0 Muskellunge
Authors: Wagner Curtis P. , Einfalt Lisa M. , Scimone Adam B. , Wahl David H.
Published: November 2009

We evaluated the effects of fin-clipping on the foraging behavior and growth of age-0 muskellunge Esox masquinongy. Fish were subjected to one of six fin-clipping treatments (one or both pectoral and pelvic fins, all paired fins, and a nonclipped control) and allowed to forage on golden shiners Notemigonus crysoleucas in laboratory pools (1.7 m in diameter). Observations of foraging behavior showed that muskellunge required a similar number of stalks, follows, and strikes to capture prey regardless of fin clip. Capture efficiencies (56%) were also similar among treatments. In outdoor pools (1.5 m in diameter), the growth and food conversion efficiency of fin-clipped muskellunge feeding on golden shiners over a 1-month period did not differ from those of unclipped controls. Fin removal did not compromise foraging behaviors and growth for juvenile muskellunge foraging on moderately evasive prey, and fish showed immediate behavioral compensation.
Growth and Survival of Four Sizes of Stocked Largemouth Bass
Authors: Diana Matthew J. , Wahl David H.
Published: November 2009

We compared growth and survival (including losses to stocking stress and predation) of four sizes of largemouth bass Micropterus salmoides in four Illinois reservoirs. Fish were stocked as small fingerlings (55 mm total length) in July, medium fingerlings (100 mm) in August, large fingerlings (150 mm) in September, and advanced fingerlings (200 mm) the subsequent spring. Survival of small fingerlings was very low (catch per unit effort < 1 fish/h of electrofishing in the fall after stocking), and fish stocked as small fingerlings were not observed in electrofishing samples after the spring following stocking. In samples collected soon after stocking, large and advanced fingerlings were larger and more abundant than other sizes. However, in subsequent sampling, there were no differences in size or survival among fish stocked as medium, large, and advanced fingerlings. Long-term growth of stocked fish was similar to that of wild fish, but survival of stocked fish was low for all sizes. Mean initial stocking mortality for fish held in cages was variable but generally low (0.0–5.6%) and was related to lake temperature at stocking. The diets of predators (primarily adult largemouth bass) contained high numbers of small-, medium-, and large-sized fingerlings after stocking, but no predation was observed on advanced fingerlings. Cost of producing fish increased with size, and cost–benefit analysis determined that medium (100-mm) fish had the greatest return per cost. We recommend stocking medium fingerlings because the stocking of larger fingerlings did not produce a significant increase in survival.
Transdermal Rotigotine: A Clinically Innovative Dopamine‐Receptor Agonist for the Management of Parkinson's Disease
Authors: Chen Jack J. , Swope David M. , Dashtipour Khashayar , Lyons Kelly E.
Published: November 2009

Rotigotine is a highly lipophilic dopamine‐receptor agonist and the first transdermally delivered agent to demonstrate efficacy and safety as monotherapy in early Parkinson's disease and to reduce “off” hours in levodopa‐treated patients with advanced Parkinson's disease. The rotigotine pharmacophore is nonergolinic and demonstrates high affinity for dopamine D2 and D3 receptors. With once‐daily application, the patch matrix provides continuous, nonfluctuating plasma drug levels at steady state, resulting in continuous and steady plasma and brain levels and striatal dopamine‐receptor stimulation. In early Parkinson's disease, doses of rotigotine up to 8 mg/24 hours demonstrate comparable efficacy to ropinirole (at doses up to 12 mg/day); in advanced Parkinson's disease, doses of rotigotine up to 16 mg/24 hours demonstrate comparable efficacy and tolerability to pramipexole (at doses up to 4.5 mg/day). In the registration trials for early and advanced Parkinson's disease, the adverse effects most commonly observed with rotigotine were minor application site reactions, dizziness, nausea, and somnolence. Doses of transdermal rotigotine can be titrated to a maintenance dose within 2–3 weeks, and the once‐daily regimen minimizes complexity of therapy. The transdermal delivery system is also an advantage when nonoral administration is desired, and the 24‐hour, continuous, nonfluctuating drug levels can improve early morning and nocturnal symptoms of Parkinson's disease. Thus, transdermally delivered rotigotine is a clinically innovative and useful addition to the dopamine‐receptor agonist class. This review summarizes the key pharmacologic and clinical data for rotigotine and provides a focused clinical context for its use in early‐to‐advanced Parkinson's disease, as well as a brief summary for its role in restless legs syndrome.
Treatment of Active Pulmonary Tuberculosis in Adults: Current Standards and Recent Advances
Authors: Hall Ronald G. , Leff Richard D. , Gumbo Tawanda
Published: November 2009

Tuberculosis is a global pandemic, with 9 million new cases of the disease and approximately 2 million deaths each year. More than 98% of patients treated for tuberculosis in the United States between 1993 and 2007 had drug‐susceptible strains. The standard treatment regimen for drug‐susceptible tuberculosis has not changed in decades and was developed on the basis of empiric observations of different treatment regimens. Only recently has the veracity of the scientific basis for standard therapy been examined. The backbone of therapy is still isoniazid, rifampin, and pyrazinamide, although fluoroquinolones are being investigated as a replacement for isoniazid. Recent population pharmacokinetic studies have demonstrated the importance of individualized dosing of isoniazid, pyrazinamide, and rifampin. Isoniazid serum clearance differs depending on the patient's number of N‐acetyltransferase 2 gene *4 (NAT2*4) alleles. Pyrazinamide serum clearance has been shown to increase with increases in body weight. Rifampin's volume of distribution, clearance, and absorption have wide between‐patient and within‐patient variability. Microbial pharmacokinetic‐pharmacodynamic (PK‐PD) indexes and targets to optimize microbial killing and minimize resistance have been identified for rifampin, isoniazid, pyrazinamide, and the fluoroquinolones. These PK‐PD indexes suggest that different doses and dosing schedules than those currently recommended could optimize therapy and perhaps shorten duration of therapy. Efflux pump inhibition is also being investigated to enhance first‐line antituberculosis drug therapy. Comorbid conditions such as diabetes mellitus and genetically determined iron overload syndromes have been associated with significantly worse patient outcomes. Therapy for these and other patient groups needs further improvement. These patient factors, the covariates for pharmacokinetic variability, and PK‐PD factors suggest the need to individualize therapy for patients with tuberculosis in order to optimize outcomes and reduce the duration of therapy.
Survival Data of Patients with Anthracycline‐ or Taxane Pretreated or Resistant Metastatic Breast Cancer
Authors: Barnett Chad M.
Published: November 2009

Metastatic breast cancer is considered incurable. Despite effective response rates achieved with anthracycline or taxane anticancer drugs, cancers in approximately one third of patients fail to respond to first‐line treatment with these agents. Patients who do respond show disease progression after a median of approximately 7–8 months. As a consequence, the development of new salvage treatments and strategies for metastatic breast cancer continues to be a high priority. However, few randomized controlled trials have been conducted in patients in whom previous treatment with anthracyclines and taxanes fails. Among those trials that have, few demonstrated an improvement in overall survival. Overall survival is considered the gold standard for evaluating the benefits of experimental cancer therapies. In addition, many investigators use progression‐free survival or time to progression. Survival outcomes from large trials of newer combinations, such as ixabepilone plus capecitabine and gemcitabine plus vinorelbine, are encouraging. They have shown significant benefits in terms of progression‐free survival, and they have revealed demonstrable benefits for several hard‐to‐treat subgroups of patients with metastatic breast cancer. Addition of the targeted agents trastuzumab, bevacizumab, and lapatinib to chemotherapy has produced significant benefits in time to progression and progression‐free survival. Ongoing research should help in determining which patients are likely to benefit from such agents when first‐ or second‐line therapy fails and in ascertaining whether this therapy can be optimized to maximize therapeutic potential and minimize unnecessary toxicity.
Mitochondrial T9098C Sequence Change in the MTATP6 Gene and Development of Severe Mitochondrial Disease After In Utero Antiretroviral Prophylaxis
Authors: Velinov Milen , Dolzhanskaya Natalia , Mendez Hermann
Published: November 2009

Mitochondrial toxicity is a well‐recognized adverse effect of nucleoside reverse transcriptase inhibitor therapy for human immunodeficiency virus (HIV) infection. Transient lactic acidosis is often observed in children born after in utero antiretroviral prophylaxis against mother‐to‐child transmission of HIV However, the extent and the mechanism of in utero adverse effects are largely unknown. We describe a 4‐year‐old girl who presented with manifestations of severe mitochondrial disease, specifically, developmental and growth delay, hypotonia, lactic acidosis, congenital cataracts, and pancreatitis. Her HIV‐positive mother was receiving lamivudine, zidovudine, and nelfinavir mesylate during her pregnancy. The child tested HIV negative after birth. She was found to have a homoplastic T9098C sequence change in the mitochondrial gene coding for adenosine 5′‐triphosphate synthase 6 (MTATP6) that was previously reported as a mitochondrial polymorphism. This polymorphism is in the MTATP6 gene‐coding sequence and leads to the replacement of a nonpolar amino acid with a polar amino acid. Because of the typical clinical manifestations of mitochondrial disorder and because of the nature of the mitochondrial sequence change, the observed polymorphism likely predisposed this patient to develop severe antiretroviral‐associated mitochondrial disease. Mitochondrial sequence alterations may be important factors in mitochondrial toxicity associated with antiretroviral treatment. Mitochondrial sequencing may be warranted in cases of persistent lactic acidosis after antiretroviral prophylaxis to further study this association.
Differentiating Incretin Therapies Based on Structure Activity, and Metabolism: Focus on Liraglutide
Authors: Grossman Samuel
Published: November 2009

The incretin effect, mediated by glucagon‐like peptide‐1 (GLP‐1) and glucose‐dependent insulinotropic polypeptide (GIP), plays an important role in the regulation of insulin secretion in response to oral glucose. The discovery of deficiencies in incretin pathways associated with development of type 2 diabetes mellitus has propelled the growth of incretin‐based therapies in patients with this disease. The basic rationale for incretin‐based therapies, including both GLP‐1‐receptor agonists and dipeptidyl peptidase‐4 (DPP‐4) inhibitors is reviewed, focusing on their roles in glucose regulation and potential therapeutic benefits. Increased awareness of the differences among incretin mimetics, GLP‐1 analogs, and DPP‐4 inhibitors, including their structures, half‐lives, dosages, hemoglobin A1c‐lowering capacities, effects on weight, and adverse events will help shape the future of these therapeutic agents. Improved understanding of the mechanism of action and clinical effects of incretin‐based therapies will help advance their appropriate use within clinical practice.
Clinical Studies of Liraglutide, a Novel, Once‐Daily Human Glucagon‐Like Peptide‐1 Analog for Improved Management of Type 2 Diabetes Mellitus
Authors: Drab Scott R.
Published: November 2009

Liraglutide, a new glucagon‐like peptide‐1 (GLP‐1)‐receptor agonist with 97% homology to human GLP‐1, can be administered once/day independent of meals in patients with type 2 diabetes mellitus. Clinical trials have demonstrated its efficacy in controlling hyperglycemia, helping patients achieve hemoglobin A1c level goals; in facilitating weight loss, and in improving indexes of β‐cell function when used alone or in combination with metformin, glimepiride, or rosiglitazone. These studies also suggest that liraglutide may be associated with modest improvements in systolic blood pressure. Data from a comparative trial of liraglutide and insulin glargine have suggested that liraglutide provides greater glycemic control with less weight gain, and another study demonstrated that liraglutide provides greater improvements in glycemic control with less hypoglycemia than exenatide and with comparable weight loss. Although liraglutide is well tolerated and is associated with low rates of hypoglycemia, transient and mild nausea can occur when therapy is initiated. However, rates of hypoglycemia appear to be lower and nausea appears to be less persistent with liraglutide than with exenatide. Even though data on the long‐term use of liraglutide are still needed, this drug may provide a useful treatment option in patients poorly controlled with dietary modification and exercise and in those whose diabetes is inadequately controlled by oral antidiabetic agents.
The Intersection of Safety and Adherence: New Incretin‐Based Therapies in Patients with Type 2 Diabetes Mellitus
Authors: Zarowitz Barbara J. , Conner Christopher
Published: November 2009

One of the challenges facing health care providers in the treatment of patients with type 2 diabetes mellitus is maintaining the balance between achieving hemoglobin A1c targets while simultaneously minimizing adverse events—most notably hypoglycemia and weight gain—that may negatively affect adherence to therapy and thus treatment outcomes. Incretin‐based treatments, such as glucagon‐like peptide‐1 (GLP‐1)‐receptor agonists and dipeptidyl peptidase‐4 (DPP‐4) inhibitors, are the newest class of therapies for the management of patients with type 2 diabetes. Data from clinical trials in which liraglutide, exenatide, saxagliptin, or sitagliptin were employed as monotherapy or added to ongoing antidiabetic treatment indicate that the incretin‐based therapies have very low risk for the development of hypoglycemia and either decrease body weight (GLP‐1‐receptor agonists) or are weight neutral (DPP‐4 inhibitors). Decreased risk for hypoglycemia and weight gain may improve adherence. Avoiding weight gain, which is commonly associated with older oral antidiabetic agents and some insulins, also has the potential to decrease the risk for cardiovascular disease. Future pharmacoeconomic studies may demonstrate translation of these benefits into good cost‐effectiveness for these therapies.
Laboratory Testing of Downhole Gas Separators
Authors: Bohorquez R. , Ananaba V. , Alabi O. , Podio A. L. , Lisigurski O. , Guzman M.
Published: November 2009

This paper provides insights on the design of downhole gas separators based on the laboratory study of various separator designs. A downhole gas separator, also known as a gas anchor, may be installed below the pump to separate free gas from the produced liquid. The free gas-produced downhole is usually separated through the casing-tubing annulus (the casing-tubing annulus acts as a natural gravity separator) while the liquid is produced through the tubing. However, inefficient gas anchor designs are widespread and an acceptable guide for their optimum design does not currently exist.

Laboratory testing of downhole gas separators has been ongoing since January 2005 at The University of Texas at Austin Petroleum Production Engineering Facility (UTAPPEF) using an instrumented full-scale model of a wellbore and separator constructed with clear acrylic pipe to visualize the fluid mechanics of the separation process. An air and water mixture is injected through the well's perforations. The air and water flow rate measurements are used to measure and define a performance plot of each separator design. The separator designs tested differed in entry-port configuration, size of dip tube, and the relative position of the separator-fluid entry ports with respect to the well's perforations. Based on the results of the tests, a new separator design that includes the effect of centrifugal forces to separate the gas and liquid phases was developed.

The results show that, for the conditions in the laboratory, 100% separation was achieved whenever the entry ports were located 1- to 2-feet (ft) below the bottom-most casing perforation thereby dispelling the predominant industry-held opinion that more distance is required between the separator-fluid entry ports and the bottom-most casing perforation. Similarly, laboratory results equally show that an optimum dip tube length of 5.5 ft is sufficient for the optimal separation of free gas from the produced liquid by the separator. This clearly runs contrary to the accepted industry practice, as many industry models employed for the estimation of dip-tube length were found to over-estimate the dip-tube length, and this subsequently results in the undesirable increased pressure drop across the separator. Lastly, the entry port geometry does not appear to have a significant impact on the separator performance as long as sufficient flow area is present. The efficiency of all gravity-driven separators was limited by the liquid velocity inside the separator annulus. When the liquid velocity inside the separator averaged approximately 6 in. per second or less, an almost-to-complete gas separation was achieved. On the other hand, the centrifugal separator had a liquid capacity 70% greater than any of the gravity-driven, static-downhole gas separators.
Acid Emulsified in Xylene: A Cost-Effective Treatment To Remove Asphaltene Deposition and Enhance Well Productivity
Authors: Fatah W. Abdel , Nasr-El-Din H.A.. A.
Published: November 2009

Emulsified acid (30 vol% diesel and 70 vol% HCl) has been used in both matrix and acid fracturing treatments. Injecting the acid in this form has several advantages including retarding the reaction of the acid with rock, reducing corrosion to well tubulars, and minimizing acid additives. However, using this acid to treat wells with asphaltene deposition requires removing asphaltene first using a suitable aromatic-based solvent, and then using a matrix acid treatment. This additional step increases the cost and time needed to execute acid treatments.

To remove asphaltene deposition and enhance well productivity, hydrochloric acid was emulsified in xylene. Xylene was the external phase, and was used to dissolve asphaltenes. Then the acid as the dispersed phase dissolved the carbonate rock, enhancing well productivity. Extensive laboratory work was performed to ensure the stability of acid-in-xylene emulsion and measure its apparent viscosity. Acid concentration was 15 wt% HCl, the acid volume fraction was 0.7, and the balance was xylene with demulsifier. All tests were conducted at room temperature and 160°F (bottomhole temperature).

The stability and apparent viscosity of emulsified acids were found to be a function of the type of hydrocarbon phase used to prepare the emulsified acid. Emulsified acids prepared with xylene had a lower apparent viscosity and were stable for relatively shorter times. A matrix acid treatment based on xylene-emulsified acid was applied in four wells without encountering operational problems. Unlike previous matrix acid treatments using regular acids, the four wells responded to the new treatment without increasing water cut, except in one well that was wet before the treatment.
Frac-Fluid Recycling and Water Conservation: A Case History
Authors: Gupta D.V.S.. V.S. , Hlidek B.T.. T.
Published: November 2009

Shallow-gas fracturing is very prevalent in western Canada. Several thousand wells are typically drilled and completed in the shallow- gas fields every year. All these wells are typically hydraulically fractured. Before 1999, after testing for microtoxicity, the flowback fluid was allowed to be land farmed in southeastern Alberta. In that year, the Alberta Energy and Utilities Board began more stringent enforcement of Guide 58, which required that flowback fluid be disposed in a disposal well.

At that time, one operator typically had a project of 300 to 400 wells with an average of 5 fracs per day during spring/sum- mer. When the fluid could no longer be land farmed, attempts were made to recycle the flowback fluid. The chemistry of the surfactant-gel fluid was insensitive to the water quality, which made the recycling concept successful. Several cost advantages were achieved, which will be detailed in the paper. These included freshwater costs, transportation costs, disposal costs, and chemical costs. An additional advantage that was realized involved a 50% reduction in the freshwater requirements for a project—a significant additional benefit because several years of drought conditions have caused water shortages in the area.

This paper will detail the chemistry of the fracturing gel, its field application, the optimized recycling operation, and the details on cost advantages achieved, as well as future direction for further reduction in freshwater usage on a project basis.
Bioenergy II: Furfural Destruction Kinetics during Sulphuric Acid-Catalyzed Production from Biomass
Authors: Marcotullio Gianluca , Cardoso Miguel A. Tavares , De Jong Wiebren , Verkooijen Ad H.M.
Published: November 2009

The interest for furfural has increased in the last years due to its potential for competing with oil derivatives as platform chemical. In addition, furfural, derived from C5 sugars, can play a key role in the valorization of the hemicellulose contained in biomass when considering the development of a modern biorefinery concept. The development of such new and competitive biorefinery processes must be based on accurate kinetic data for the reactions involving furfural in the conditions used for its production.This work addresses the determination of furfural destruction kinetics in aqueous acidic environment, using sulphuric acid as catalyst, in the temperature range 150 - 200°C, acid concentration range 36.4 - 145.5 mM and furfural initial concentration between 60.4 and 72.5 mM. These studies were carried out using a recently built lab-scale titanium reactor that enables liquid phase reactions in a relatively broad range of conditions.The obtained results show that destruction of furfural follows first-order reaction kinetics within the range of temperature and acid concentration evaluated. Moreover, the proposed kinetic model takes into account the effects of temperature and acid dilution on the ions activity, and thus H3O+, by using the electrolyte Non-Random Two-Liquid (eNRTL) model. By using this approach, the rate constant dependence on temperature could be described by the Arrhenius law and thus the activation energy could be estimated as being 125.1 [kJ/mol] and the pre-exponential factor 3.711011[s-1]. Separation of different reaction products was achieved by means of HPLC, these products were not yet completely identified. Contrarily to what is reported in previous works, formic acid formation from furfural under the tested conditions can be regarded as playing a far less pronounced role than suggested before.
A Comparison of Combustion of Coal Chars in O2/CO2 and O2/N2 Mixtures - Isothermal TGA Studies
Authors: Liu Hao
Published: November 2009

Two chars prepared from parent coals of a high volatile bituminous coal and an anthracite coal were subjected to isothermal combustion tests in a thermogravimetric analyser (TGA). The chars were burned in mixtures of O2/CO2 and O2/N2 with O2 concentrations of 3%, 6%, 10%, 21% and 30% and combustion temperature ranging from 723 K to 1163 K. Experimental results show that replacing the inert nitrogen gas in the oxidizer with CO2 has little influence on the measured reactivity of coal chars under conditions of the experiments. The measured reactivity of each char was found to be approximately first order (0.88  0.90) to the concentration of O2 in the O2/CO2 mixtures. As char combustion tests were conducted under relatively high temperatures conditions, internal and external effectiveness factors were estimated in order to derive combustion kinetics of both chars. The values of activation energy for both chars, obtained by taking account of both the internal and external effectiveness factors (i.e. with correction), were very much in line with the literature data. The activation energy of the bituminous coal char combustion in O2/CO2 was found to be 96323 (without correction)  108893 (with correction) kJ/kmol within the temperature range of 723  873 K, whereas the activation energy of the anthracite char was found to be 125716 (without correction)  140486 (with correction) kJ/kmol within the temperature range of 773  973 K.
Biodiesel Production from Jatropha curcas Oil Using Potassium Carbonate as an Unsupported Catalyst
Authors: Baroi Chinmoy , Yanful Ernest K , Bergougnou Maurice A.
Published: November 2009

Jatropha curcas (JTC) oil, an inedible vegetable oil, can be a substitute feedstock for traditional food crops in the production of environment friendly and renewable fuel (biodiesel). In the present study, unsupported potassium carbonate was used as a catalyst to provide an understanding of the catalytic activity in the transesterification reaction. Researching the potential and the behavior of potassium carbonate is very important because every biomass ash contains this compound in a significant amount. It can be extracted by using classical extraction or leaching technologies. During the biodiesel production reaction, the formation of soap as a byproduct was also monitored using the FTIR-ATR method. From this study it was observed that the transesterification of JTC oil to JTC biodiesel appeared to be complete within 15 minutes when a 5 wt% (based on the wt. of the oil) potassium carbonate, 6:1 methanol to oil molar ratio, 60°C or a 4 wt% potassium carbonate, 9:1 methanol to oil molar ratio and 60°C reaction temperature were used.
Trade and Variety in a Model of Endogenous Product Differentiation
Authors: Lorz Oliver , Wrede Matthias
Published: November 2009

This paper sets up a model of endogenous product differentiation to analyze the variety effects of international trade. In our model multi-product firms decide not only about the number of varieties they will supply but also about the degree of horizontal differentiation between these varieties. Firms can raise the degree of differentiation by investing variety-specific fixed costs. In this setting, we analyze how trade integration, i.e. an increase in market size, influences the number of firms in the market, the number of product varieties supplied by each firm, and the degree of differentiation between these varieties.