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161.
To relate the pharmacokinetics of orally administered lansoprazole in healthy adult Jordanian men with CYP2C19 polymorphisms and to determine the percentage of CYP2C19 polymorphism in Jordanian population and the allelic frequency of CYP2C19*2 and CYP2C19*3. A total of 78 healthy Jordanian volunteers were included in this study from three different bioequivalence studies, one of these studies which included 26 volunteers was done on lansoprazole. Genotyping for CYP2C19*1, CYP2C19*2, CYP2C19*3 was done for all 78 volunteers, the data of genotyping of all subjects used for screening the frequency of different genotypes and the allelic frequency of different polymorphisms in healthy Jordanian men, the pharmacokinetics and genotyping data for the study of lansoprazole was matched and compared to investigate presence of statistical differences in pharmacokinetic parameters. In Jordanian subjects, the allele frequencies of the CYP2C19*2 and CYP2C19*3 mutation were 0.16 and 0, respectively. The concentration–time curves in the two groups [homozygote extensive metabolizer (homEM, n = 19) and heterozygote extensive metabolizer (homEM, n = 7)] groups were fitted to a non-compartment model. In the homEM and in the hetEM groups, the main kinetic parameters were as follows: Tmax (2.1875 ± 0.777) and (2.54 ± 1.87) h, Cmax (697.875 ± 335) and (833.58 ± 436.26) mg/l, t1/2 (1.3 ± 0.43) and (2.38 ± 1.64) h, AUC(0→∞) were (1,684.9 ± 888) and (3,609.8 ± 318) mg h l−1, respectively. The Jordanian population showed similarities in CYP2C19 allele and genotype distribution pattern with Caucasians and Africans. CYP2C19 allele and poor metabolizer (PM) genotype frequencies in the Jordanian population are distinct from populations’ from East Asia such as Japanese and Koreans. Although lower pharmacokinetic parameters were found in homEM compared to hetEM but there was no significant difference between the two groups (P < 0.05).  相似文献   
162.
Hoteit I  Kharma N  Varin L 《Bio Systems》2012,109(1):57-71
We present a detailed and extendable design of the first synchronous single-input delay flip-flop implemented as a gene regulatory network in Escherichia coli (E. coli). The device, which we call the BioD, has one data input (transacting RNA), one clock input (far-red light) and an output that reports the state of the device using green fluorescent protein (GFP). The proposed design builds on Gardner's toggle switch, to provide a more sophisticated device that can be synchronized with other devices within the same cell, and which requires only one data input. We provide a mathematical model of the system and simulation results. The results show that the device behaves in line with desired functionality. Further, we discuss the constraints of the design, which pertain to ranges of parameter values. The BioD is extended via the addition of an update function and input and output interfaces. The result is the BioFSM, which constitutes a synchronous and modular finite state machine, which uses an update function to change its state, stored in the BioD. The BioFSM uses its input and output interfaces for inter-cellular communications. This opens the door to the design of a circular cellular automata (the BioCell), which is envisioned as a number of communicating E. coli colonies, each made of clones of one BioFSM.  相似文献   
163.
Patients having stereo-electroencephalography (SEEG) electrode, subdural grid or depth electrode implants have a multitude of electrodes implanted in different areas of their brain for the localization of their seizure focus and eloquent areas. After implantation, the patient must remain in the hospital until the pathological area of brain is found and possibly resected. During this time, these patients offer a unique opportunity to the research community because any number of behavioral paradigms can be performed to uncover the neural correlates that guide behavior. Here we present a method for recording brain activity from intracranial implants as subjects perform a behavioral task designed to assess decision-making and reward encoding. All electrophysiological data from the intracranial electrodes are recorded during the behavioral task, allowing for the examination of the many brain areas involved in a single function at time scales relevant to behavior. Moreover, and unlike animal studies, human patients can learn a wide variety of behavioral tasks quickly, allowing for the ability to perform more than one task in the same subject or for performing controls. Despite the many advantages of this technique for understanding human brain function, there are also methodological limitations that we discuss, including environmental factors, analgesic effects, time constraints and recordings from diseased tissue. This method may be easily implemented by any institution that performs intracranial assessments; providing the opportunity to directly examine human brain function during behavior.  相似文献   
164.
To integrate heterogeneous and large omics data constitutes not only a conceptual challenge but a practical hurdle in the daily analysis of omics data. With the rise of novel omics technologies and through large-scale consortia projects, biological systems are being further investigated at an unprecedented scale generating heterogeneous and often large data sets. These data-sets encourage researchers to develop novel data integration methodologies. In this introduction we review the definition and characterize current efforts on data integration in the life sciences. We have used a web-survey to assess current research projects on data-integration to tap into the views, needs and challenges as currently perceived by parts of the research community.  相似文献   
165.

Setting

Public tuberculosis (TB) clinics in urban Morocco.

Objective

Explore risk factors for TB treatment default and develop a prediction tool. Assess consequences of default, specifically risk for transmission or development of drug resistance.

Design

Case-control study comparing patients who defaulted from TB treatment and patients who completed it using quantitative methods and open-ended questions. Results were interpreted in light of health professionals’ perspectives from a parallel study. A predictive model and simple tool to identify patients at high risk of default were developed. Sputum from cases with pulmonary TB was collected for smear and drug susceptibility testing.

Results

91 cases and 186 controls enrolled. Independent risk factors for default included current smoking, retreatment, work interference with adherence, daily directly observed therapy, side effects, quick symptom resolution, and not knowing one’s treatment duration. Age >50 years, never smoking, and having friends who knew one’s diagnosis were protective. A simple scoring tool incorporating these factors was 82.4% sensitive and 87.6% specific for predicting default in this population. Clinicians and patients described additional contributors to default and suggested locally-relevant intervention targets. Among 89 cases with pulmonary TB, 71% had sputum that was smear positive for TB. Drug resistance was rare.

Conclusion

The causes of default from TB treatment were explored through synthesis of qualitative and quantitative data from patients and health professionals. A scoring tool with high sensitivity and specificity to predict default was developed. Prospective evaluation of this tool coupled with targeted interventions based on our findings is warranted. Of note, the risk of TB transmission from patients who default treatment to others is likely to be high. The commonly-feared risk of drug resistance, though, may be low; a larger study is required to confirm these findings.  相似文献   
166.
Oral mucosa is continuously exposed to environmental forces and has to be constantly renewed. Accordingly, the oral mucosa epithelium contains a large reservoir of epithelial stem cells necessary for tissue homeostasis. Despite considerable scientific advances in stem cell behavior in a number of tissues, fewer studies have been devoted to the stem cells in the oral epithelium. Most of oral mucosa stem cells studies are focused on identifying cancer stem cells (CSC) in oral squamous cell carcinomas (OSCCs) among other head and neck cancers. OSCCs are the most prevalent epithelial tumors of the head and neck region, marked by their aggressiveness and invasiveness. Due to their highly tumorigenic properties, it has been suggested that CSC may be the critical population of cancer cells in the development of OSCC metastasis. This review presents a brief overview of epithelium stem cells with implications in oral health, and the clinical implications of the CSC concept in OSCC metastatic dissemination.  相似文献   
167.
Cyclooxygenase and lipoxygenase arachidonate products, including prostaglandins (PGs), leukotrienes (LTs), and hydroxyeicosatetraenoic acids (HETEs), are known to modulate inflammation within tissues and can serve as important etiologic factors in carcinogenesis. Eicosanoid content in tissues is typically determined either as a single molecular species through antibody-based assays or by high-performance liquid chromatography after addition of an exogenous substrate such as arachidonic acid. Unfortunately, the methods currently in use are either time-consuming or complicated. Here we report a method for simultaneously identifying eicosanoids appearing as endogenous bioactive lipids in in vivo settings using LC/MS/MS. The analyses indicate marked differences in endogenous eicosanoid content between malignant tissue types suggesting a need for selective therapeutic approaches. As a demonstration of the utility of the method, we present data to show that the technique can be used to distinguish eicosapentaenoic acid-derived formation of PGE(3) from PGE(2) in murine prostate tissue. The method has also been applied to an examination of endogenous eicosanoid metabolism in 7,12-dimethylbenz[a]anthracene (DMBA)-induced oral cancer in hamsters demonstrating the inflammatory nature of this type of cancer with elevated levels of both PGE(2) and LTB(4). In addition, the concentration of the eicosanoid 13-hydroxyoctadecadienoic acid was 67.6% lower in DMBA treated specimens than in control specimens. Thus, our method provides a powerful tool for measuring modulation of eicosanoid metabolites in various preclinical and clinical tissues and may be useful in studies of the endogenous changes in eicosanoid metabolism at various stages of cancer development.  相似文献   
168.
The carnivorous bladderworts (Utricularia) possess complicated suction traps. Remarkably, information on the prey trapped is relatively sparse. We have conducted a detailed survey on the prey spectra found in traps of selected aquatic bladderworts (U. australis, U. vulgaris) occurring in ponds in northeastern Germany. A close examination of more than 200 traps revealed cladocerans, copepods, rotiferas, ciliates and insect larvae as being common prey.Of particular interest was the considerable amount of phytoplankton (i.e. algae, cyanobacteria) found in the traps. In total, more than 160 algae species (among others, Kirchneriella lunaris, Scenedesmus quadricauda and S. acuminatus) belonging to more than 50 genera were present, with Chlorophyceae being dominant. The role of the vegetarian diet for nutrient supply of bladderworts is discussed.  相似文献   
169.
Objective : To study the effects of a 12-week weight loss strategy involving increased physical activity, self-selected hypocaloric diet, and group support on psychological well-being, quality of life, and health practices in moderately obese women. Methods; Eighty women aged 20–49 years weighing between 20–50% above 1983 Metropolitan Life Insurance Tables were randomly assigned to a weight loss intervention (6279 kJ/week of physical activity, 33,258-41,462 kJ/week diet and weekly meetings) or served as controls. Subjects were tested pre and post 12-weeks. Results : The intervention group lost significant (p<0.001) body weight (kg) and body fat (%) compared to controls (-6.07 ± 4.01 kg vs. 1.31 ± 1.28 kg; 36.8%-32.5% vs. 36.2%-36.0%). Intervention subjects vs. controls achieved significant improvements (p<0.001) in body cathexis (X Change 18.6 ± 16.7 vs. 0.7 ± 8.6) and estimation of ability to achieve physical fitness (X Change 8.1 ± 7.1 vs. 0.9 ± 5.9). Various quality of life indices also improved (p<0.01) in the intervention group compared to controls (physical function: X Change 13.5.2 ± 16.7 vs. 1.4 ± 9.5; vitality: X change 21.7 ± 17.9 vs. 2.9 20.8; mental health: X change 10.4 ± 16.0 vs. 2.3 ± 10.1). Similarly, physical activity levels also improved significantly (p<0.0001) in the intervention group (4.4 ± 2.3 vs. 0.6 ± 1.3; on NASA 0–7 scale). Conclusions : Practical weight loss practices such as increased activity, self-selected hypocaloric diet, and group support are effective for weight loss and yield significant health and psychological benefits in moderately obese females.  相似文献   
170.
Capsule The number of Lesser Kestrel Falco naumanni breeding pairs in Morocco has varied significantly and positively over thirteen years (1998–2010), between six colonies and over the 13-year period at each colony. The mean growth rate was λ?=?1.13?±?0.02. This positive trend is consistent with the current Least Concern conservation status of the species in the IUCN Red List.  相似文献   
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