Glycerol: An unexpected major metabolite of energy metabolism by the human malaria parasite

<p>Abstract</p> <p>Background</p> <p>Malaria is a global health emergency, and yet our understanding of the energy metabolism of the principle causative agent of this devastating disease, <it>Plasmodium falciparum</it>, remains rather basic. Glucose was shown to be an essential nutritional requirement nearly 100 years ago and since this original observation, much of the current knowledge of <it>Plasmodium </it>energy metabolism is based on early biochemical work, performed using basic analytical techniques (e.g. paper chromatography), carried out almost exclusively on avian and rodent malaria. Data derived from malaria parasite genome and transcriptome studies suggest that the energy metabolism of the parasite may be more complex than hitherto anticipated. This study was undertaken in order to further characterize the fate of glucose catabolism in the human malaria parasite, <it>P. falciparum</it>.</p> <p>Methods</p> <p>Products of glucose catabolism were determined by incubating erythrocyte-freed parasites with D-[1-¹³C] glucose under controlled conditions and metabolites were identified using ¹³C-NMR spectroscopy.</p> <p>Results</p> <p>Following a 2 h incubation of freed-<it>P. falciparum </it>parasites with 25 mM D-[1-¹³C] glucose (<it>n </it>= 4), the major metabolites identified included; [3-¹³C] lactate, [1,3-¹³C] glycerol, [3-¹³C] pyruvate, [3-¹³C] alanine and [3-¹³C] glycerol-3-phosphate. Control experiments performed with uninfected erythrocytes incubated under identical conditions did not show any metabolism of D-[1-¹³C] glucose to glycerol or glycerol-3-phosphate.</p> <p>Discussion</p> <p>The identification of glycerol as a major glucose metabolite confirms the view that energy metabolism in this parasite is more complex than previously proposed. It is hypothesized here that glycerol production by the malaria parasite is the result of a metabolic adaptation to growth in O₂-limited (and CO₂elevated) conditions by the operation of a glycerol-3-phosphate shuttle for the re-oxidation of assimilatory NADH. Similar metabolic adaptations have been reported previously for other microaerobic/anaerobic organisms, such as yeast, rumen protozoa and human parasitic protozoa.</p> <p>Conclusion</p> <p>These data highlight the need to re-evaluate the carbon and redox balance of this important human pathogen, ultimately leading to a better understanding of how the parasite is able to adapt to the variable environments encountered during parasite development and disease progression.</p

PERCEIVED BARRIERS TO BREAST CANCER SCREENING AMONG SAUDI WOMEN AT PRIMARY CARE SETTING

Introduction: Screening for breast cancer (BC) is of low rate in Saudi Arabia; although it is provided in the country free of charge to the population. This cross-sectional study aimed at investigating the perceived barriers towards BC screening in Al Hassa, Saudi Arabia. Participants and Methods:  A total of 816 adult Saudi women aged ≥ 30 years attending for routine primary health services or accompanying patients at the selected primary health care centers (PHCs) were randomly selected from 12 PHCs (8 urban and four rural) using multi-stage sampling method. Participants were invited to personal interview using semi-structured data collection instrument including inquiries about socio-demographics, reproductive history, previous histories of diagnosed breast lesions and breast cancer. The perceived individual barriers towards screening, their attitudes, the reasons for not attending previously held screening campaigns in Al Hassa, were also included. Results: Low utilization of BC screening being significantly positively associated with woman’s age, higher educational status, higher family income, using hormonal contraception and positive history of previous breast as shown by the results of the logistic regression model. Exploratory factor analysis showed that personal fears (especially fear of doctors/examiners, fear of hospitals and health facilities and fear of consequences/results) were the major factors that hinder women from utilizing the free of charge BC screening with high loading eigenvalue of 3.335, explaining 30.4% of the barriers. Conclusion: Educational interventions aim at improving breast cancer knowledge and addressing barriers   should be incorporated as core component of the screening program in Saudi Arabia.

Effectiveness of incentivised adherence and abstinence monitoring in buprenorphine maintenance : a pragmatic, randomised controlled trial

Acknowledgements The authors wish to thank the patients and staff at the National Rehabilitation Centre for their participation and to the NRC director general, Dr. Hamad Al Ghaferi, for his advice and support. Work on this study was included as part of H.E.'s doctoral studies and supervisor J.M. kindly acknowledge support from the Scholarship Office at the Ministry of Presidential Affairs, United Arab Emirates.Peer reviewedPublisher PD

Overview on Blood Transfusion-Transmitted Diseases

As it is important for the Blood transfusion to be extremely safe, some measures have to be taken long safeguarded the blood supply from the major transfusion transmissible diseases (TTIs).&nbsp; The risk of transfusion-transmitted infection (TTI) rises with the number of donors exposed, and the effects of TTI are frequently more severe in immune compromised people. TTIs (hepatitis B virus [HBV], HIV, and hepatitis C virus [HCV]) are examples of typical transfusion-transmitted infectious agents. As a result of the gradual application of nucleic acid-amplification technology (NAT) screening for HIV, HCV, and HBV, the residual risk of infected window-period donations has been minimized. Nonetheless, infections emerge far more frequently than is commonly acknowledged, needing ongoing surveillance and individual assessment of transfusion-associated risk. Although there is a constant need to monitor present dangers owing to established TTI, the ongoing issues in blood safety are mostly related to surveillance for developing agents, as well as the creation of quick reaction systems when such agents are detected

Immunohistochemical evaluation of human epidermal growth factor receptor 2 and estrogen and progesterone receptors in breast carcinoma in Jordan

INTRODUCTION: Although breast carcinoma (BC) is the most common malignancy affecting Jordanian females and the affected population in Jordan is younger than that in the West, no information is available on its biological characteristics. Our aims in this study are to evaluate the expression of estrogen receptor (ER) and progesterone receptor (PR) and Her-2/neu overexpression in BC in Jordan, and to compare the expression of these with other prognostic parameters for BC such as histological type, histological grade, tumor size, patients' age, and number of lymph node metastases. METHOD: This is a retrospective study conducted in the Department of Pathology at Jordan University of Science and Technology. A confirmed 91 cases of BC diagnosed in the period 1995 to 1998 were reviewed and graded. We used immunohistochemistry to evaluate the expression of ER, PR, and Her-2. Immunohistochemical findings were correlated with age, tumor size, grade and axillary lymph node status. RESULTS: Her-2 was overexpressed in 24% of the cases. The mean age of Her-2 positive cases was 42 years as opposed to 53 years among Her-2 negative cases (p = 0.0001). Her-2 expression was inversely related to ER and PR expression. Her-2 positive tumors tended to be larger than Her-2 negative tumors with 35% overexpression among T3 tumors as opposed to 22% among T2 tumors (p = 0.13). Her-2 positive cases tended to have higher rates of axillary metastases, but this did not reach statistical significance. ER and PR positive cases were seen in older patients with smaller tumor sizes. CONCLUSION: Her-2 overexpression was seen in 24% of BC affecting Jordanian females. Her-2 overexpression was associated with young age at presentation, larger tumor size, and was inversely related to ER and PR expression. One-fifth of the carcinomas were Her-2 positive and ER negative. This group appears to represent an aggressive form of BC presenting at a young age with large primary tumors and a high rate of four or more axillary lymph node metastases

Socializing One Health: an innovative strategy to investigate social and behavioral risks of emerging viral threats

In an effort to strengthen global capacity to prevent, detect, and control infectious diseases in animals and people, the United States Agency for International Development’s (USAID) Emerging Pandemic Threats (EPT) PREDICT project funded development of regional, national, and local One Health capacities for early disease detection, rapid response, disease control, and risk reduction. From the outset, the EPT approach was inclusive of social science research methods designed to understand the contexts and behaviors of communities living and working at human-animal-environment interfaces considered high-risk for virus emergence. Using qualitative and quantitative approaches, PREDICT behavioral research aimed to identify and assess a range of socio-cultural behaviors that could be influential in zoonotic disease emergence, amplification, and transmission. This broad approach to behavioral risk characterization enabled us to identify and characterize human activities that could be linked to the transmission dynamics of new and emerging viruses. This paper provides a discussion of implementation of a social science approach within a zoonotic surveillance framework. We conducted in-depth ethnographic interviews and focus groups to better understand the individual- and community-level knowledge, attitudes, and practices that potentially put participants at risk for zoonotic disease transmission from the animals they live and work with, across 6 interface domains. When we asked highly-exposed individuals (ie. bushmeat hunters, wildlife or guano farmers) about the risk they perceived in their occupational activities, most did not perceive it to be risky, whether because it was normalized by years (or generations) of doing such an activity, or due to lack of information about potential risks. Integrating the social sciences allows investigations of the specific human activities that are hypothesized to drive disease emergence, amplification, and transmission, in order to better substantiate behavioral disease drivers, along with the social dimensions of infection and transmission dynamics. Understanding these dynamics is critical to achieving health security--the protection from threats to health-- which requires investments in both collective and individual health security. Involving behavioral sciences into zoonotic disease surveillance allowed us to push toward fuller community integration and engagement and toward dialogue and implementation of recommendations for disease prevention and improved health security

Collision/reaction cell ICP-MS with shielded torch and sector field ICP-MS for the simultaneous determination of selenium isotopes in biological matrices

The determinations of selenium isotopes in biological samples were performed using both inductively coupled plasma collision/reaction cell quadruple mass spectrometer (CRC-ICP-QMS) and inductively coupled plasma sector field mass spectrometers (SF-ICP-MS). To significantly decrease the argon-based interferences at m/z 74 (36Ar38Ar), 76 ( 38Ar38Ar, 40Ar36Ar), 78 ( 38Ar40Ar), and 80 (40Ar40Ar), the gas-flow rates of a helium and hydrogen mixture used in the collision cell were optimized to 1.0 mL/min H2 and 3.5 mL/min He. Under the optimized condition, the precisions for natural selenium isotope ratio measurements of both instruments were evaluated and compared using 100 ppb Se standard solution. A modified external calibration quantification method was applied for the simultaneous determination of clinically used enriched selinocompounds ( 77Se-selenate, 82Se-selenite, 76Se- methylseleninic acidIV, 78Se-methylselenonic acid VI) and to examine their fate in rat organs (liver, kidney, and lung). © 2010 Springer Science+Business Media, LLC

Attitudes Towards Fake News: A Systematic Literature Review

The rise of social media has provided a means for the spread of fake news, factual false information that is used to further a financial, political or societal agenda. The response to fake news on social media can be from individual users, social media platform companies, or respective national governments. This systematic literature review was designed to determine whether there is commonality across cultures and nations as to fake news exposure, response to encountering fake news on social media, and attitudes towards mediating efforts. A total of five published journal articles were selected, each using quantitative methods and representing five distinct geographical areas. These articles formed the bases for a systematic literature review that answered the research questions concerned with attitudes towards the threat of fake news, responses to fake news encountered on social media platforms, and attitudes towards efforts to curb fake news, whether by individuals, social media platform companies, or governments. Results showed universal recognition of fake news as a potential or real threat, mixed results as to whether fake news is read or shared by respondents, and mixed results regarding which actor (people, companies or governments) should lead mitigation efforts. These results emphasize the cultural and societal differences that must be considered when investigating fake news, particularly with the intention to develop recommendations or guidelines for its reduction