bluuebunny/crossref_metadata_2025 huggingface dataset:
Diabetes and pancreatic cancer
Authors: Cui YunFeng , Andersen Dana K
Published: July 2012

Epidemiological studies clearly indicate that the risk of pancreatic cancer (PC) is increased in diabetic patients, but most studies focus on overall diabetes or type 2 diabetes mellitus (T2DM), and there are few studies on the risks of type 1 and type 3c (secondary) diabetes. Possible mechanisms for increased cancer risk in diabetes include cellular proliferative effects of hyperglycemia, hyperinsulinemia, and abnormalities in insulin/IGF receptor pathways. Recently, insulin and insulin secretagogues have been observed to increase the PC risk, while metformin treatment reduces the cancer risk in diabetic subjects. In addition, anticancer drugs used to treat PC may either cause diabetes or worsen coexisting diabetes. T3cDM has emerged as a major subset of diabetes and may have the highest risk of pancreatic carcinoma especially in patients with chronic pancreatitis. T3cDM is also a consequence of PC in at least 30% of patients. Distinguishing T3cDM from the more prevalent T2DM among new-onset diabetic patients can be aided by an assessment of clinical features and confirmed by finding a deficiency in postprandial pancreatic polypeptide release. In conclusion, diabetes and PC have a complex relationship that requires more clinical attention. The risk of developing PC can be reduced by aggressive prevention and treatment of T2DM and obesity and the prompt diagnosis of T3cDM may allow detection of a tumor at a potentially curable stage.
Lipopolysaccharide-induced murine embryonic resorption involves nitric oxide-mediated inhibition of the NAD+-dependent 15-hydroxyprostaglandin dehydrogenase
Authors: Aisemberg Julieta , Bariani María V , Vercelli Claudia A , Wolfson Manuel L , Franchi Ana M
Published: July 2012

The initial inactivation of prostaglandins (PGs) is mediated by 15-hydroxyprostaglandin dehydrogenase (15-PGDH). PGs are potent mediators of several biological processes, including inflammation and reproduction. In uterus, PGs play a key role in infection-induced pregnancy loss, in which concentration of this mediator increased. This process is accompanied with the induction of nitric oxide synthase expression and a marked increase in uterine levels of nitric oxide. There is no information concerning nitric oxide contribution to potential changes in PG catabolism, but experimental evidence suggests that nitric oxide modulates PG pathways. The specific objectives of the study were to evaluate the protein expression of HPGD (15-PGDH) and to characterize the nitric oxide-dependent regulation of this enzyme in a model of lipopolysaccharide (LPS)-induced embryonic resorption. Results show that LPS decreased HPGD protein expression and augmented PGE synthase activity; therefore, PGE2 levels increased in uterus in this inflammatory condition. Just as LPS, the treatment with a nitric oxide donor diminished HPGD protein expression in uterine tissue. In contrast, the inhibition of nitric oxide synthesis both in control and in LPS-treated mice increased 15-PGDH levels. Also, we have found that this enzyme and PGE2 levels are not modulated by peroxynitrite, an oxidant agent derived from nitric oxide. This study suggests that LPS and nitric oxide promote a decrease in the ability of the uterus for PG catabolism during bacterially triggered pregnancy loss in mice.
Impact of flaxseed intake upon metabolic syndrome indicators in female Wistar rats
Authors: Brant Lívia Hipólito Cardozo , Cardozo Ludmila Ferreira Medeiros de França , Velarde Luís Guillermo Coca , Boaventura Gilson Teles
Published: July 2012

PURPOSE: To evaluate whether the prolonged consumption of flaxseed minimize the factors that trigger MS in healthy rats. METHODS: Pregnant rats were divided immediately after delivery into two groups during the lactation period, a control group (CG) receiving casein-based diet with 17% of protein, and a Flaxseed group (FG) with casein-based diet plus 25% of flaxseed. At weaning, 12 offspring of each group continued to receive the same feed but with 10% of protein up to 200 days old. RESULTS: FG showed a significant reduction in body weight (p=0.001), total cholesterol levels (p<0.0001), triglycerides (p=0.0001), and glucose (p=0.001). CONCLUSION: The flaxseed alters the indicators related to development of metabolic syndrome, because it has beneficial effects on lipids and glucose profiles and prevents the excess of body weight gain.
Biliopancreatic diversion with duodenojejunal exclusion associated with truncal vagotomy: a new proposal for type 2 diabetes mellitus treatment
Authors: Alleotti Edson , Palma Rogério Tadeu , Pinto Junior Paulo Engler , Bento José Antonio , Yonamine Raquel , Campos André Luiz Lopes Cardoso , Waisberg Jaques
Published: July 2012

PURPOSE: To evaluate the effectiveness of the biliopancreatic diversion surgery with duodenojejunal exclusion in combination with truncal vagotomy in type 2 diabetes mellitus (T2DM) patients with overweight or class I or II obesity. METHODS: The study included ten patients with T2DM and class I or II obesity or overweight who were subjected to biliopancreatic diversion with duodenojejunal exclusion in combination with truncal vagotomy. The blood glucose levels during the pre- and postoperative periods were compared using the Friedman test. The significance level adopted was 5%. RESULTS: There were significant differences between preoperative and postoperative blood glucose levels at three months (p=0.01), six months (p=0.001) and 12 months (p=0.001). There was also a significant difference between one month postoperative blood glucose and six months postoperative blood glucose (p=0.01). Glycosylated hemoglobin levels decreased in 80% of patients, there was marked improvement in their lipid profiles, and the average BMI reduction was 7.0±1.5 kg/m² at 12 months after the surgery. CONCLUSION: In patients with type 2 diabetes mellitus associated with class I/II obesity or overweight, performing biliopancreatic diversion with duodenojejunal exclusion in combination with truncal vagotomy resulted in glycemic control, reduction of excess weight, and improvement of lipid profile 12 months after the surgery.
Cryopreserved tracheal segments: a new tool for bench surgical training in thoracic surgery
Authors: Sotres-Vega Avelina , Villalba-Caloca Jaime , Ramirez-Zamora Farid , Pérez-Covarrubias Diana , Santibáñez-Salgado J. Alfredo
Published: July 2012

PURPOSE: To present a new low-cost high fidelity bench model of cryopreserved trachea that can be used to learn surgical skills from medical students to cardiothoracic surgery fellows. METHODS: Ten tracheas were harvested from ten non-trachea related research dogs at the moment of euthanasia. Each trachea was trimmed in six or seven rings segments. They were cryopreserved and stored during 60 days. The day programmed for surgical skills practice, they were thawed to room temperature. RESULTS: Forty segments have been used. After defrosting, all the segments kept their normal anatomic shape and structural integrity. Two incisions were made on every tracheal segment and sutured with running or separate stitches with 5-0 polypropilene. There were no complications such as cartilage ruptures, neither tears on the mucosae, the cartilages nor the membranous posterior membrane. CONCLUSIONS: The cryopreserved trachea is a high fidelity, practical, reproducible, portable, low-cost bench model. It allows cardiothoracic fellows to learn how to handle a trachea, as well as to perfect their surgical and suture abilities before applying them on a real patient's trachea.
Review of experimental models for inducing hepatic cirrhosis by bile duct ligation and carbon tetrachloride injection
Authors: Marques Thamirys Guimarães , Chaib Eleazar , Fonseca Juliana Hamati da , Lourenço Ana Cecília Rodrigues , Silva Felipe Duarte , Ribeiro Jr Marcelo Augusto Fontenelle , Galvão Flavio Henrique Ferreira , D'Albuquerque Luiz Augusto Carneiro
Published: July 2012

PURPOSE: To present a review about a comparative study of bile duct ligation versus carbon tetrachloride Injection for inducing experimental liver cirrhosis. METHODS: This research was made through Medline/PubMed and SciELO web sites looking for papers on the content "induction of liver cirrhosis in rats". We have found 107 articles but only 30 were selected from 2004 to 2011. RESULTS: The most common methods used for inducing liver cirrhosis in the rat were administration of carbon tetrachloride (CCl4) and bile duct ligation (BDL). CCl4 has induced cirrhosis from 36 hours to 18 weeks after injection and BDL from seven days to four weeks after surgery. CONCLUSION: For a safer inducing cirrhosis method BDL is better than CCl4 because of the absence of toxicity for researches and shorter time for achieving it.
Effect of cement kiln dust on geopolymer composition and its resistance to sulfate attack
Authors: Khater H. M.
Published: July 2012

Utilization of cement kiln dust (CKD) with its high alkali content in the activation of geopolymer specimens to create nonconventional cementitious binders was investigated. Relatively high alkaline content of CKD is predominant factor preventing its recycling in cement manufacture. CKD could provide the necessary environment to activate geopolymer materials depending on water-soluble alkalis and sulfate compounds. Materials used in this investigation are ground granulated blast furnace slag (water cooled slag (WCS)), air cooled slag, CKD, and calcined kaolin. Calcinations process was done by kaolin firing at 750 C for 3 h. Alkaline activation by 2% NaOH along with the added cement dust was studied as compared with that not activated by sodium hydroxide. Curing was performed at 38 C under 100% relative humidity. Results showed that 25% CKD is the optimum ratio for WCS-geopolymer formation and activation using 2% NaOH along with 25% CKD results in best enhancement in mechanical as well as microstructural characteristics. Activation of metakaolin by 50% CKD has the lowest mechanical properties due to calcium deficiency that bind geopolymer matrix. Effect of 5% magnesium sulfate on WCS and metakaolin activated by CKD results in an enhancement in their mechanical properties up to 3 months, while subjected to a strength loss up to 6 months.
Glucose Transporter and Na+ / glucose Cotransporter as Molecular Targets of Anti-Diabetic Drugs
Authors: Asano Tomoichiro , Ogihara Takehide , Katagiri Hideki , Sakoda Hideyuki , Ono Hiraku , Fujishiro Midori , Anai Motonobu , Kurihara Hiroki , Uchijima Yasunobu
Published: July 2012

Glucose transporters, or membrane proteins, which incorporate glucose into the cell, can be divided into two groups: the facilitative type glucose transporter (GLUT), and the sodium / glucose cotransporter (SGLT). Among the GLUT family isoforms, GLUT4 is particularly important for maintaining glucose metabolism homeostasis since it is involved in insulin or exercise-induced glucose transport into muscle and adipose tissues via movement from intracellular sites to the plasma membrane in response to stimulation. Thus, agents which induce GLUT4 translocation or improve insulin sensitivity, involved in this insulininduced step, hold the promise of being potent anti-diabetic drugs. On the other hand, SGLT is expressed specifically in the intestines and kidneys. Oral administration of a SGLT inhibitor, T-1095, lowers the blood glucose concentration via excretion of glucose in the urine, due to suppression of renal SGLT function. In addition to this direct blood glucose lowering effect, T-1095 has been shown to restore impaired insulin secretion from pancreatic β-cells, as well as to improve insulin resistance in muscle and liver. Thus, this SGLT inhibitor is regarded as a novel and promising agent for the treatment of diabetes mellitus.
5-(1-Substituted) Alkyl Pyrimidine Nucleosides as Antiviral (herpes) Agents
Authors: Kumar Rakesh
Published: July 2012

The treatment of viral diseases remains one of the major challenges to modern medicine. During the past two decades there has been increased recognition of the consequences of serious viral illnesses that are not controlled by vaccination. These illnesses include human immunodeficiency virus, human herpes viruses, and viruses that cause hepatitis. There are now eight pathogens recognized in the herpes virus family that cause infections in humans. Infections by the herpes viruses are opportunistic and often life-threatening, leading to significant morbidity and mortality in the increasing number of chronically immune compromised individuals such as AIDS patients, cancer patients and transplant recipients on immunosuppressive therapy. Nearly all individuals with AIDS are infected with one or more of the herpes viruses. Antiviral therapy with guanosine nucleoside analogs acyclovir and ganciclovir has had a major impact on diseases caused by herpes simplex virus type-1 and type-2 (HSV-1, HSV-2), Varicella zoster virus (VZV), and human cytomegalovirus (HCMV) but development of resistant virus strains and the absence of any effective treatment for other members of the herpes family provide a stimulus for increased search of new agents effective against various herpes viruses. Pyrimidine nucleosides have taken up an important role in the therapy of virus infection. Significant progress in the study of anti-herpes nucleosides has been made by the advent of 5-substituted pyrimidine nucleosides such as 5-iodo-, 5-ethyl-, 5-(2-chloroethyl)-, and (E)-5-(2-bromovinyl)- derivatives of 2-deoxyuridine. These are highly specific inhibitors of HSV-1, HSV-2, and / or VZV infections. However, Epstein Barr virus (EBV) and HCMV are much less sensitive to these agents. In 5-substituted pyrimidine nucleosides the nature of substituents, particularly at the C-5 position, has been found to be an important determinant of anti-herpes activity. Structural requirements at the C-2 carbon of the 5-substituent of pyrimidine nucleosides have been well established for anti-herpes activity. However, there is little qualitative or mechanistic knowledge of the derivatives with substitution at the C-1 carbon of the 5-substituent of pyrimidine nucleosides. During the last few years of our research, we have investigated a variety of C-1 functionalized substituents at the 5-position of the pyrimidine nucleosides to determine their usefulness as antiviral (herpes) agents. In the 5-(1-substituted) group of pyrimidine nucleosides, we demonstrated that novel substituents present at the C-1 carbon of the 5-side chain of the pyrimidine nucleosides are important determinants of potent and broad spectrum antiviral (herpes) activity including EBV and HCMV. In this article the work on design, synthesis and structure activity relationships of several 5-[(1-substituted) alkyl (or vinyl)] pyrimidine nucleoside derivatives as potential inhibitors of herpes viruses is reviewed.
Wealth Inequality and Health: A Political Economy Perspective
Authors: Nowatzki Nadine R.
Published: July 2012

Despite a plethora of studies on income inequality and health, researchers have been unable to make any firm conclusions as a result of methodological and theoretical limitations. Within this body of research, there has been a call for studies of wealth inequality and health. Wealth is far more unequally distributed than income and is conceptually unique from income. This paper discusses the results of bivariate cross-sectional analyses of the relationship between wealth inequality (Gini coefficient) and population health (life expectancy and infant mortality) in 14 wealthy countries. The results confirm that wealth inequality is associated with poor population health. Both unweighted and weighted correlations between wealth inequality and health are strong and significant, even after controlling for a variety of potential aggregate-level confounders, including gross domestic product per capita, and after excluding the United States, the most unequal country. The results are strongest for female life expectancy and infant mortality. The author outlines potential pathways through which wealth inequality might affect health, using specific countries to illustrate. The article concludes with policy recommendations that could contribute to a more equitable distribution of wealth and, ultimately, decreased health disparities.
Poverty and the Violation of Human Rights: A Proposed Conceptual Framework
Authors: Schuftan Claudio
Published: July 2012

The paper proposes a conceptual framework linking the causes of poverty with the causes of human rights violations. Both are presented as outcomes of a cascading chain of determinants grouped as immediate, underlying, and basic causes. The framework will make situation analyses focused on poverty and human rights better adjusted to the reality on the ground. It is also the first step in using the human rights-based approach, now an established methodology being used by a growing number of health and development practitioners and seen by the United Nations system as the way forward. The framework also provides guidance to communities in identifying, in a participatory way, causes of the problems that affect them. The framework is presented in a diagram format followed by a list of the major determinants in each causal level.
Fukushima Update: Radioactive Fallout and Mortality Increases in the United States: Is There a Correlation?
Authors: Mangano Joseph J. , Sherman Janette D.
Published: July 2012

Our publication of “An Unexpected Mortality Increase in the United States Follows Arrival of the Radioactive Plume from Fukushima: Is There a Correlation?” in the International Journal of Health Services 42(1) reported an unusually elevated number of excess deaths in 122 U.S. cities during the 14 weeks following the mid-March 2011 arrival of airborne radioactive fallout from Japan. The publication has received considerable attention from scientists, media, and the public, since it is the first peer-reviewed publication to examine population-based data before and after the meltdowns at Fukushima. Most of the responses have been objective or supportive, with a minority offering criticisms of the methods and results. In this paper, we respond to several of the critiques, offering supportive evidence from our research and supportive research in the medical literature. We hope our comments are constructive and we view our research as a correlation, and potential evidence of a causal link, between radioactive exposures from Fukushima and increased health risk, underscoring the need for additional and prompt reports on the topic.
Two-Year Follow-Up of a Prospective Clinical Trial of Cyclosporine for Frequently Relapsing Nephrotic Syndrome in Children
Authors: Ishikura Kenji , Yoshikawa Norishige , Nakazato Hitoshi , Sasaki Satoshi , Iijima Kazumoto , Nakanishi Koichi , Matsuyama Takeshi , Ito Shuichi , Yata Nahoko , Ando Takashi , Honda Masataka
Published: July 2012

Background and objectives

Although the safety and efficacy of cyclosporine in children with frequently relapsing nephrotic syndrome (FRNS) have been confirmed, no prospective follow-up data on relapse after cyclosporine have appeared. This study is a prospective follow-up trial after 2-year treatment with cyclosporine to investigate cyclosporine dependency after its discontinuation.

Design, setting, participants, & measurements

Participants who had undergone 2-year protocol treatment with microemulsified cyclosporine for FRNS between January 2000 and December 2005 were followed for an additional 2 years. The primary end point was relapse-free survival after the complete discontinuation of cyclosporine, and the secondary end point was regression-free survival (time to regression to FRNS).

Results

After exclusion of 7 patients who showed regression to FRNS during the 2-year treatment period, 49 children (median age, 6.5 years) were followed, and classified as children without (n=32; group A) and with (n=17; group B) relapse during the initial cyclosporine treatment. Overall, relapse-free survival probability at 24 months after cyclosporine discontinuation was 15.3% and regression to FRNS-free survival probability was 40.8%. By group, the probability of relapse-free survival was significantly higher in group A (17.9%) than in group B (8.3%) (P<0.001).

Conclusions

Children with FRNS who receive cyclosporine are at high risk of relapse after discontinuation, particularly those who experience relapse during cyclosporine treatment.
Pulmonary Embolism in Patients with CKD and ESRD
Authors: Kumar Gagan , Sakhuja Ankit , Taneja Amit , Majumdar Tilottama , Patel Jayshil , Whittle Jeff , Nanchal Rahul
Published: July 2012

Background and objectives

CKD and ESRD are growing burdens. It is unclear whether these conditions affect pulmonary embolism (PE) risk, given that they affect both procoagulant and anticoagulant factors. This study examined the frequency and associated outcomes of PE in CKD and ESRD.

Design, setting, participants, & measurements

The Healthcare Cost and Utilization Project’s Nationwide Inpatient Sample was used to estimate the frequency and outcomes of PE in adults with CKD and ESRD. Hospitalizations for the principal diagnosis of PE and presence of CKD or ESRD were identified using International Classification of Diseases,
Ninth Revision codes. Data from the annual US Census and US Renal Data System reports were used to calculate the number of adults with CKD, ESRD, and normal kidney function (NKF) as well as the annual incidence of PE in each group. Logistic regression modeling was used to compare in-hospital mortality among persons admitted for PE who had ESRD or CKD to those without these conditions.

Results

The annual frequency of PE was 527 per 100,000, 204 per 100,000, and 66 per 100,000 persons with ESRD, CKD, and NKF, respectively. In-hospital mortality was higher for persons with ESRD and CKD (P<0.001) compared with persons with NKF. Median length of stay was longer by 1 day in CKD and 2 days in ESRD than among those with NKF.

Conclusions

Persons with CKD and ESRD are more likely to have PE than persons with NKF. Once they have PE, they are more likely to die in the hospital.
Exploring the Association between Macroeconomic Indicators and Dialysis Mortality
Authors: Kramer Anneke , Stel Vianda S. , Caskey Fergus J. , Stengel Benedicte , Elliott Robert F. , Covic Adrian , Geue Claudia , Cusumano Ana , MacLeod Alison M. , Jager Kitty J.
Published: July 2012

Background and objectives

Mortality on dialysis varies greatly worldwide, with patient-level factors explaining only a small part of this variation. The aim of this study was to examine the association of national-level macroeconomic indicators with the mortality of incident dialysis populations and explore potential explanations through renal service indicators, incidence of dialysis, and characteristics of the dialysis population.

Design, setting, participants, & measurements

Aggregated unadjusted survival probabilities were obtained from 22 renal registries worldwide for patients starting dialysis in 2003–2005. General population age and health, macroeconomic indices, and renal service organization data were collected from secondary sources and questionnaires. Linear modeling with log–log transformation of the outcome variable was applied to establish factors associated with survival on dialysis.

Results

Two-year survival on dialysis ranged from 62.3% in Iceland to 89.8% in Romania. A higher gross domestic product per capita (hazard ratio=1.02 per 1000 US dollar increase), a higher percentage of gross domestic product spent on healthcare (1.10 per percent increase), and a higher intrinsic mortality of the dialysis population (i.e., general population-derived mortality risk of the dialysis population in that country standardized for age and sex; hazard ratio=1.04 per death per 10,000 person years) were associated with a higher mortality of the dialysis population. The incidence of dialysis and renal service indicators were not associated with mortality on dialysis.

Conclusions

Macroeconomic factors and the intrinsic mortality of the dialysis population are associated with international differences in the mortality on dialysis. Renal service organizational factors and incidence of dialysis seem less important.
Association of Race and Insurance Type with Delayed Assessment for Kidney Transplantation among Patients Initiating Dialysis in the United States
Authors: Johansen Kirsten L. , Zhang Rebecca , Huang Yijian , Patzer Rachel E. , Kutner Nancy G.
Published: July 2012

Background and objectives

The extent to which racial and socioeconomic disparities in access to kidney transplantation are related to not being assessed for transplant suitability before or shortly after the time of initiation of dialysis is not known. The aims of this study were to determine whether there were disparities based on race, ethnicity, or type of insurance in delayed assessment for transplantation and whether delayed assessment was associated with lower likelihood of waitlisting and kidney transplantation.

Design, setting, participants, & measurements

This retrospective cohort study used data from the US Renal Data System and included 426,489 adult patients beginning dialysis in the United States between January 1, 2005 and September 30, 2009 without prior kidney transplant.

Results

Overall, 12.5% of patients had reportedly not been assessed for transplantation. Patients without private insurance were more likely to be reported as not assessed (multivariable adjusted odds ratio=1.33, 95% confidence interval=1.28–1.40 for Medicaid), with a pronounced racial disparity but no ethnic disparity among patients aged 18 to <35 years (odds ratio=1.27, 95% confidence interval=1.13–1.43; P<0.001 for interaction with age). Not being assessed for transplant around the time of dialysis initiation was associated with lower likelihood of waitlisting in multivariable analysis (hazard ratio=0.59, 95% confidence interval=0.57–0.62 in the first year) and transplantation (hazard ratio=0.46, 95% confidence interval=0.41–0.51 in the first year), especially within the first 2 years.

Conclusions

Racial and insurance-related disparities in transplant assessment potentially delay transplantation, particularly among younger patients.
High-level multicore programming with C++11
Authors: Szűgyi Zalán , Török Márk , Pataki Norbert , Kozsik Tamás
Published: July 2012

Nowadays, one of the most important challenges in programming is the
efficient usage of multicore processors. All modern programming languages
support multicore programming at native or library level. C++11, the next
standard of the C++ programming language, also supports multithreading at a
low level. In this paper we argue for some extensions of the C++ Standard
Template Library based on the features of C++11. These extensions enhance
the standard library to be more powerful in the multicore realm. Our
approach is based on functors and lambda expressions, which are major
extensions in the language. We contribute three case studies: how to
efficiently compose functors in pipelines, how to evaluate boolean operators
in parallel, and how to efficiently accumulate over associative functors.
Development and Preliminary Evaluation of Student-Authored Electronic Cases
Authors: Trace Chris , Baillie Sarah , Short Nick
Published: July 2012

In medical education, virtual patients are now widely used to support and enhance clinical teaching. However, there is still only a limited adoption of similar methods in veterinary education. This paper describes an initiative at the Royal Veterinary College (RVC) in London to develop student-authored cases during clinical rotations that were subsequently adapted for self-directed learning in the undergraduate curriculum as virtual patients. This approach was designed to enhance the quality of the clinical learning experience, assist in the development of clinical reasoning skills, and complement the existing teaching caseload. The creation of virtual patients involved a two-stage process. In the first stage, students compiled clinical case data and media from patients admitted to the teaching hospitals. They then used these resources to develop electronic cases using a customized Microsoft PowerPoint template that were presented at grand rounds to clinicians and other students. In the second stage, selected cases were further developed with the integration of self-assessment and additional media to create virtual patients for use in teaching. A survey was used to gather feedback on students' experiences in creating and using electronic cases. It was completed by 163 final-year students (81%) and the results indicated that all respondents had created electronic cases on one or more rotations (mean=4.3 rotations, range=1–9). Overall, the feedback suggested that the students found creating and using these cases useful and that the experience improved their approach to a case.
Workplace-Based Assessment in a Primary-Care Setting
Authors: Hecker Kent G. , Norris Jill , Coe Jason B.
Published: July 2012

Workplace-based assessment (WBA) is the process of directly observing students' work within a clinical setting, assessing their performance, and providing specific, goal oriented feedback. Assessment methods used for workplace-based assessment include tools developed for clinical interaction (e.g., the mini clinical evaluation exercise [mini-CEX]), for procedural or technical skills (e.g., the direct observation of procedural skills [DOPS]), and multi-source feedback tools to assess interpersonal and technical skills. While several of these assessment methods are being adopted by veterinary schools to evaluate students' progress through their clinical rotations, there is little reported at this time about their utility and effectiveness within the veterinary context. This article provides an introduction to the use of these tools and offers guidance in selecting appropriate methods for assessment in the primary health care setting.
Regulation of Autophagy by Glucose in Mammalian Cells
Authors: Moruno Félix , Pérez-Jiménez Eva , Knecht Erwin
Published: July 2012

Autophagy is an evolutionarily conserved process that contributes to maintain cell homeostasis. Although it is strongly regulated by many extracellular factors, induction of autophagy is mainly produced by starvation of nutrients. In mammalian cells, the regulation of autophagy by amino acids, and also by the hormone insulin, has been extensively investigated, but knowledge about the effects of other autophagy regulators, including another nutrient, glucose, is more limited. Here we will focus on the signalling pathways by which environmental glucose directly, i.e., independently of insulin and glucagon, regulates autophagy in mammalian cells, but we will also briefly mention some data in yeast. Although glucose deprivation mainly induces autophagy via AMPK activation and the subsequent inhibition of mTORC1, we will also comment other signalling pathways, as well as evidences indicating that, under certain conditions, autophagy can be activated by glucose. A better understanding on how glucose regulates autophagy not only will expand our basic knowledge of this important cell process, but it will be also relevant to understand common human disorders, such as cancer and diabetes, in which glucose levels play an important role.
Correlation between Protein Sequence Similarity and Crystallization Reagents in the Biological Macromolecule Crystallization Database
Authors: Lu Hui-Meng , Yin Da-Chuan , Liu Yong-Ming , Guo Wei-Hong , Zhou Ren-Bin
Published: July 2012

The protein structural entries grew far slower than the sequence entries. This is partly due to the bottleneck in obtaining diffraction quality protein crystals for structural determination using X-ray crystallography. The first step to achieve protein crystallization is to find out suitable chemical reagents. However, it is not an easy task. Exhausting trial and error tests of numerous combinations of different reagents mixed with the protein solution are usually necessary to screen out the pursuing crystallization conditions. Therefore, any attempts to help find suitable reagents for protein crystallization are helpful. In this paper, an analysis of the relationship between the protein sequence similarity and the crystallization reagents according to the information from the existing databases is presented. We extracted information of reagents and sequences from the Biological Macromolecule Crystallization Database (BMCD) and the Protein Data Bank (PDB) database, classified the proteins into different clusters according to the sequence similarity, and statistically analyzed the relationship between the sequence similarity and the crystallization reagents. The results showed that there is a pronounced positive correlation between them. Therefore, according to the correlation, prediction of feasible chemical reagents that are suitable to be used in crystallization screens for a specific protein is possible.
Prediction of Acute Mammalian Toxicity Using QSAR Methods: A Case Study of Sulfur Mustard and Its Breakdown Products
Authors: Ruiz Patricia , Begluitti Gino , Tincher Terry , Wheeler John , Mumtaz Moiz
Published: July 2012

Predicting toxicity quantitatively, using Quantitative Structure Activity Relationships (QSAR), has matured over recent years to the point that the predictions can be used to help identify missing comparison values in a substance’s database. In this manuscript we investigate using the lethal dose that kills fifty percent of a test population (the LD50) for determining relative toxicity of a number of substances. In general, the smaller the LD50 value, the more toxic the chemical, and the larger the LD50 value, the lower the toxicity. When systemic toxicity and other specific toxicity data are unavailable for the chemical(s) of interest, during emergency responses, LD50 values may be employed to determine the relative toxicity of a series of chemicals. In the present study, a group of chemical warfare agents and their breakdown products have been evaluated using four available rat oral QSAR LD50 models. The QSAR analysis shows that the breakdown products of Sulfur Mustard (HD) are predicted to be less toxic than the parent compound as well as other known breakdown products that have known toxicities. The QSAR estimated break down products LD50 values ranged from 299 mg/kg to 5,764 mg/kg. This evaluation allows for the ranking and toxicity estimation of compounds for which little toxicity information existed; thus leading to better risk decision making in the field.
Sensitivity of Coastal Flood Risk Assessments to Digital Elevation Models
Authors: Van de Sande Bas , Lansen Joost , Hoyng Claartje
Published: July 2012

Most coastal flood risk studies make use of a Digital Elevation Model (DEM) in addition to a projected flood water level in order to estimate the flood inundation and associated damages to property and livelihoods. The resolution and accuracy of a DEM are critical in a flood risk assessment, as land elevation largely determines whether a location will be flooded or will remain dry during a flood event. Especially in low lying deltaic areas, the land elevation variation is usually in the order of only a few decimeters, and an offset of various decimeters in the elevation data has a significant impact on the accuracy of the risk assessment. Publicly available DEMs are often used in studies for coastal flood risk assessments. The accuracy of these datasets is relatively low, in the order of meters, and is especially low in comparison to the level of accuracy required for a flood risk assessment in a deltaic area. For a coastal zone area in Nigeria (Lagos State) an accurate LiDAR DEM dataset was adopted as ground truth concerning terrain elevation. In the case study, the LiDAR DEM was compared to various publicly available DEMs. The coastal flood risk assessment using various publicly available DEMs was compared to a flood risk assessment using LiDAR DEMs. It can be concluded that the publicly available DEMs do not meet the accuracy requirement of coastal flood risk assessments, especially in coastal and deltaic areas. For this particular case study, the publically available DEMs highly overestimated the land elevation Z-values and thereby underestimated the coastal flood risk for the Lagos State area. The findings are of interest when selecting data sets for coastal flood risk assessments in low-lying deltaic areas.
Minimally displaced tibial tuberosity avulsion fracture in nine skeletally immature large breed dogs
Authors: DeCamp C. E. , Ritter M. , Probst C. W. , Dejardin L. M. , Priddy N. , Hayashi K. , Johnston S. A. , von Pfeil D. J. F.
Published: July 2012

Objective: The objective of this study was to describe the clinical and radiographic features, as well as the treatment and outcome of minimally displaced tibial-tuberosity-avulsion-fractures (MDTTAF).

Materials and methods: Signalment, history, diagnostics, therapy, and outcome were recorded. Follow-up was documented as re-examination, radiographic assessment or telephone conversation.

Results: Nine large breed dogs that were presented with lameness originating from the proximal tibia were included. All showed signs of pain when pressure was applied to the tibial tuberosity. There was no stifle instability or intra-articular disease. The main feature on mediolateral radiographs was a widened tibial-tuberosity-physis with reactive new bone and loss of edge definition of the epiphyseal and metaphyseal margins. Non-surgical treatment was chosen in eight dogs, and surgery in one dog. Radiographic follow-up showed progressive closure of the tibial-tuberosity-physis and healing. Clinical signs resolved at a median of 28 days (range: 14–120).

Discussion: Minimally displaced tibial-tuberosity-avulsion-fractures should be a differential diagnosis in skeletally immature large breed dogs older than nine months of age with signs of subtle pelvic-limb lameness, and signs of proximal tibial pain, but no evidence of stifle joint disease. Thorough clinical examination and critical review of bilateral radiographs are important to diagnose MDTTAF. The outcome in these cases suggests that the prognosis for MDTTAF is excellent. Age and size of the affected dogs in this study differ from an earlier publication that illustrated more severely displaced tibial tuberosity avulsion fractures, occurring mainly in terriers around five months of age.
Cytotoxicity of antimalarial plant extracts from Kenyan biodiversity to the brine shrimp, Artemia salina L. (Artemiidae)
Authors: Nguta Joseph Mwanzia , Mbaria James Mucunu , Gakuya Daniel Waweru , Gathumbi Peter Karuri , Kabasa John David , Kiama Stephen Gitahi
Published: July 2012

Artemia salina (Artemiidae), the brine shrimp larva, is an invertebrate used in the alternative test to determine toxicity of chemicals and natural products. In this study the medium lethal concentration fifty (LC50 values) of 45 antimalarial plant extracts and positive controls, cyclophosphamide and etoposide were determined using Artemia salina (Artemiidae). Out of the 45 organic extracts screened for activity against Artemia salina larvae, 23 (51%) of the crude extracts demonstrated activity at or below 100 μg/mL, and were categorized as having strong cytotoxic activity, 18 (40%) of the crude extracts had LC50 values between 100 μg/mL and 500 μg/mL, and were categorized as having moderate cytotoxicity, 2 (4.5%) of the crude extracts had LC50 values between 500 μg/mL and 1000 μg/mL, and were considered to have weak cytotoxic activity, while 2 (4.5%) of the crude extracts had LC50 values greater than 1000 μg/mL and were considered to be non toxic. Approximately 20% (9) of the aqueous extracts demonstrated activity at or below 100 g/mL and were considered to have strong cytotoxic activity, 40% (18) of the screened aqueous crude extracts had LC50 values between 100 μg/mL and 500 μg/mL and were considered to be moderately cytotoxic, 16% (7) of the crude extracts had LC50 values between 500 μg/mL and 1000 μg/mL and were considered to have weak cytotoxic activity while 24% (11) of the aqueous extracts had LC50 values greater than 1000μg/mL and were categorized as non toxic The positive controls, cyclophosphamide and etoposide exhibited strong cytotoxicity with LC50 values of 95 μg/mL and 6 μg/mL respectively in a 24 hour lethality study, validating their use as anticancer agents. In the current study, 95.5% of all the screened organic extracts and 76% of the investigated aqueous extracts demonstrated LC50 values <1000 g/mL, indicating that these plants could not make safe anti-malarial treatments. This calls for dose adjustment amongst the community using the plant extracts for the treatment of malaria and chemical investigation for isolation of bioactive compounds responsible for the observed toxicity.
CAD May Not be Necessary for Microcalcifications in the Digital era, CAD May Benefit Radiologists for Masses
Authors: Destounis Stamatia V. , Arieno Andrea L. , Morgan Renee C.
Published: July 2012

Objective:

The aim of this study was to evaluate the effectiveness of computer-aided detection (CAD) to mark the cancer on digital mammograms at the time of breast cancer diagnosis and also review retrospectively whether CAD marked the cancer if visible on any available prior mammograms, thus potentially identifying breast cancer at an earlier stage. We sought to determine why breast lesions may or may not be marked by CAD. In particular, we analyzed factors such as breast density, mammographic views, and lesion characteristics.

Materials and Methods:

Retrospective review from 2004 to 2008 revealed 3445 diagnosed breast cancers in both symptomatic and asymptomatic patients; 1293 of these were imaged with full field digital mammography (FFDM). After cancer diagnosis, in a retrospective review held by the radiologist staff, 43 of these cancers were found to be visible on prior-year mammograms (false-negative cases); these breast cancer cases are the basis of this analysis. All cases had CAD evaluation available at the time of cancer diagnosis and on prior mammography studies. Data collected included patient demographics, breast density, palpability, lesion type, mammographic size, CAD marks on current- and prior-year mammograms, needle biopsy method, pathology results (core needle and/or surgical), surgery type, and lesion size.

Results:

On retrospective review of the mammograms by the staff radiologists, 43 cancers were discovered to be visible on prior-year mammograms. All 43 cancers were masses (mass classification included mass, mass with calcification, and mass with architectural distortion); no pure microcalcifications were identified in this cohort. Mammograms with CAD applied at the time of breast cancer diagnosis were able to detect 79% (34/43) of the cases and 56% (24/43) from mammograms with CAD applied during prior year(s). In heterogeneously dense/extremely dense tissue, CAD marked 79% (27/34) on mammograms taken at the time of diagnosis and 56% (19/34) on mammograms with CAD applied during the prior year(s). At time of diagnosis, CAD marked lesions in 32% (11/34) on the craniocaudal (CC) view, 21% (7/34) on the mediolateral oblique (MLO) view. Lesion size of those marked by CAD or not marked were similar, the average being 15 and 12 mm, respectively.

Conclusion:

CAD marked cancers on mammograms at the time of diagnosis in 79% of the cases and in 56% of the cases from the mammograms with CAD applied in the prior year(s). Our review demonstrated that CAD can mark invasive breast carcinomas in even dense breast tissue. CAD marked a significant portion on the CC view only, which may be an indicator to radiologists to be especially vigilant when a lesion is marked on this view.
Endovascular Management of Fusiform Superior Cerebellar Artery Aneurysms: A Series of Three Cases with Review of Literature
Authors: Alurkar Anand , Karanam Lakshmi Sudha P. , Nayak Suresh , Oak Sagar
Published: July 2012

Distal superior cerebellar artery (SCA) aneurysms are rare. Fusiform aneurysms of SCA are rarer and more challenging to treat. Parent artery occlusion by endovascular coiling is the treatment option for these cases. Presence of good collateral circulation and paucity of perforators from S1 and S2 segments makes this a feasible option. From 2007 to 2010, we treated three patients (two men and one woman between the ages of 42 to 64 years) with distal fusiform SCA aneurysms using endovascular coiling. All the patients presented with symptoms of rupture and were treated in the acute phase. Informed and written high-risk consent was given by all patients prior to the procedure. Successful angiographic and clinical outcome was achieved in all three patients. Endovascular treatment of fusiform SCA aneurysms with coils is a safe and feasible option in the management of this rare entity.
Hypoglycemia due to an adult-onset nesidioblastosis, a diagnostic and management dilemma
Authors: Qintar Mohammed , Sibai Firas , Taha Mohammad
Published: July 2012

We describe a case of a 40 year old patient with recurrent severe fasting and postprandial symptomatic hypoglycemia that occurred 6 years after gastric bypass surgery. The hypoglycemia was associated with increased insulin and C peptide but all diagnostic modalities for localizing an insulinoma were negative. Medical management failed to control symptoms and the patient underwent subtotal pancreatectomy. Surgical tissue examination confirmed the diagnosis of noninsulinoma pancreatogenous hypoglycaemia syndrome (NIPHS) or nesidioblastosis. Initially after surgery the patient had full remission but after 6 months hypoglycemia recurred. However, this time it was well-controlled with octreotide treatment.
Annual variability in light modulation of bacterial heterotrophic activity in surface northwestern Mediterranean waters
Authors: Ruiz-González Clara , Galí Martí , Lefort Thomas , Cardelús Clara , Simó Rafel , Gasol Josep M.
Published: July 2012

The effect of photosynthetically available radiation (PAR; 400–700 nm) and ultraviolet radiation (UVR; 280–400 nm) on marine bacterial heterotrophic activity was assessed monthly throughout a seasonal cycle in Blanes Bay (northwestern Mediterranean Sea). Seawater samples amended with 3H‐leucine were exposed to solar radiation under three radiation treatments: PAR + UVR (280–700 nm), PAR + UVA (320–700 nm), and PAR only. Parallel reference incubations in the dark and under a fixed artificial light source (PAR only) were also performed. Exposure to high UVR doses caused strong inhibition of 3H‐leucine incorporation rates (LIR), whereas natural PAR doses did not cause overall significant effects. Within UVR, UVA radiation accounted for most of the reduction in LIR, and this effect was modulated by the proportionality of the experimental light to the previous light exposure history of the samples. Constant (artificial) PAR‐only exposure led to a general but seasonally variable increase in bacterial heterotrophic production compared to the dark controls, with large increases in spring and lower changes during summer. This pattern was likely caused by the stimulation of the bacterial group Gammaproteobacteria, which showed higher numbers of cells active in 3H‐leucine uptake after light exposure. Again, the previous light history of the samples seemed to partly explain the measured effects. Overall, our results show variable responses of bacterial activities to light manipulations, depending on seasonally changing light conditions and communities, and stress the importance of realistic simulation of light exposure conditions for ecosystem‐relevant photobiological studies with microbial plankton.