pH-dependent binding of the Epsin ENTH domain and the AP180 ANTH domain to PI(4,5)P2-containing bilayers

Epsin and AP180 are essential components of the endocytotic machinery, which controls internalization of protein receptors and other macromolecules at the cell surface. Epsin and AP180 are recruited to the plasma membrane by their structurally and functionally related N-terminal ENTH and ANTH domains that specifically recognize PtdIns(4,5)P₂. Here, we show that membrane anchoring of the ENTH and ANTH domains is regulated by the acidic environment. Lowering the pH enhances PtdIns(4,5)P₂ affinity of the ENTH and ANTH domains reinforcing their association with lipid vesicles and monolayers. The pH dependency is due to the conserved histidine residues of the ENTH and ANTH domains, protonation of which is necessary for the strong PtdIns(4,5)P₂ recognition, as revealed by liposome binding, surface plasmon resonance, NMR, monolayer surface tension and mutagenesis experiments. The pH sensitivity of the ENTH and ANTH domains is reminiscent to the pH dependency of the FYVE domain suggesting a common regulatory mechanism of membrane anchoring by a subset of the PI-binding domains.     

Ultrasound evaluation of visceral fat and metabolic risk factors during early pregnancy

Objective: The objective was to study the relationships between ultrasound estimated visceral fat and metabolic risk factors during early pregnancy. Research Methods and Procedures: Thirty consecutive healthy pregnant women at 11 to 14 weeks of gestation were studied. Maximum subcutaneous fat thickness (SFT) and visceral fat thickness (VFT) were successfully measured by ultrasound. Fasting plasma glucose, insulin, triglycerides, total cholesterol, high‐density lipoprotein cholesterol (HDL‐C), and blood pressure were measured. Insulin resistance was calculated by using the homeostasis model assessment (HOMA). Results: VFT significantly correlated with diastolic blood pressure (r = 0.37, p = 0.04), glycemia (r = 0.37, p = 0.04), insulinemia (r = 0.59, p = 0.001) insulin sensitivity (HOMA; r = 0.59, p = 0.001), triglycerides (r = 0.58, p = 0.03), HDL‐C (r = ?0.39, p = 0.03), and total cholesterol/HDL‐C ratio (p = 0.002), whereas SFT was significantly correlated with only diastolic blood pressure (p = 0.03). VFT better significantly correlated with the metabolic risk factors than pre‐gestational BMI [r = 0.39, p = 0.03 for insulinemia, r = 0.42, p = 0.02 for insulin sensitivity (HOMA), and r = 0.49, p = 0.01 for triglycerides and not significant for the rest]. Discussion: Visceral fat thickness can be easily measured by ultrasound at early pregnancy and correlates better than BMI with metabolic risk factors.     

新型声学造影剂在常规诊断超声频率下对在 体肾脏及离体培养细胞影响的研究

目的：评价新型超声造影剂在常规诊断超声频率下对组织细胞结构的影响。资料和方法：体外培养的人近曲小管上皮细胞分为造影剂无超声照射组,单纯超声照射组,MI 1．5,造影剂加超声照射组。MI 0．28,造影剂加超声照射组,MI 1．5。超声照射时间为10分钟。实验完后用2.5％的戊二醛固定4小时,送电镜室做扫描电镜。正常免肾经耳缘静脉按0．02ml／kg团注脂氟显（新桥医院超声科实验室自制）,用6MHz的超声频率照射,MI 0．28。照射10分钟。活体取肾皮质。放入3．0％的戊二醛溶液中固定,送电镜室做投射电镜。结果：离体培养的人近端小管上皮细胞单纯超声照射、单纯加造影剂、造影剂加超声照射MI 0．28和MI 1．5时扫描电镜观察细胞形态无改变,细胞表面未见异常。透射电镜观察免肾小囊腔和肾小管上皮细胞超微结构未见特异性政变。结论：新型脂质体声学造影剂在诊断剂量超声照射下不会对组织细胞结构产生影响。新型脂质体声学造影剂在诊断剂量下是安全的。     

Biofumigation and Enhanced Biodegradation: Opportunity and Challenge in Soilborne Pest and Disease Management

Management of soilborne pests and diseases in cropping systems is often highly challenging—in implementation of acceptable methodologies and in dealing with secondary problems. The phase-out of methyl bromide brings this into particularly sharp focus. There is a need for diversified options and alternatives to fill different roles across the soilborne pest and disease management spectrum, but flexibility is limited, as practicalities demand that they fit into a prophylactic methodology. It is against such a backdrop that expectations and promotion of alternatives must be set. There is also a need to recognize potentially serious problems that may have been masked under historical management regimes, but for which the nature of the system offers little scope to avoid or manage.

Biofumigation is the beneficial use of Brassica green manures that release isothiocyanates chemically similar to methyl isothiocyanate, the active agent from the synthetic fumigant metam sodium, which is used as a substitute for methyl bromide in some systems. A systematic approach to research into biofumigation, specifically aimed at overcoming a long history of empiricism, has seen significant recent advances in both basic and applied knowledge. A key development has been achievement of maximal biofumigation potential through greatly enhanced release of appropriate isothiocyanates into soil. These advances have led to commercial adoption, demonstrating that biofumigation, when applied to appropriate production systems, can have efficacy and offer cost savings. Crucially, these systematically derived research and development findings and their adoption now provide the impetus for self-sustaining further development and market penetration of the concept. Despite this success, biofumigation is not seen as being sufficiently powerful or practical in implementation to be an alternative to methyl bromide on a broad scale and misdirection in that regard could be counterproductive to more appropriately targeted further development.

Enhanced microbial biodegradation is a cryptic phenomenon that can diminish the efficacy of soil-applied pesticides, including isothiocyanates and most other currently available methyl bromide substitutes. Because methyl bromide is not susceptible, the phenomenon has potentially serious implications in intensive production systems switching from methyl bromide to reliance on other compounds that are. It is an intractable problem once induced. Avoidance of its onset is the only feasible management strategy. This has been aided for some particularly vulnerable environments by recent clarification of key risk factors associated with soil type, soil pH, and calcium content.     

An innovative solution to reduce muscle deformation during ultrasonography data collection

Background3D freehand ultrasound enables the creation of volumetric data. The acquisition of morphological features, such as muscle volume, is influenced by the variations in force applied to the skin with the ultrasound probe. To minimise the deformations, a concave-shaped plastic mount combined with a custom-shaped gel pad was developed for the ultrasound head, named Portico. This study analyses to what extent the Portico reduces muscle deformation and corresponding errors in estimating muscle volume.MethodTwenty medial gastrocnemius (MG) muscles were assessed (10 from typically developing children; 10 from children with spastic cerebral palsy). Two repetitions were acquired in each of the following approaches: (1) with the lower leg submerged in a water tank as a non-deformed reference; (2) probe-on-skin (PoS) as the conventional approach and (3) the newly introduced Portico. PoS and Portico data were registered with respect to the ones corresponding in a water tank. An in-house software package (Py3DFreeHandUS) was used to process the data and MG volume was estimated using MeVisLab. The minimal detectable change (MDC) was calculated.ResultsWith respect to the PoS approach, the Portico reduced muscle deformation by 46%. For both the typically developing and spastic cerebral palsy cohorts, lower MDCs were found when using the Portico.DiscussionDespite the improvements, the Portico did not yield statistically more reliable MG volume estimations than the traditional PoS approach. Further improvement can be attained by optimising the fit between the gel pad and the curvature of the limb, using a larger choice of Portico geometries.     

Role of β-adrenergic receptors in the anti-obesity and anti-diabetic effects of zinc-α2-glycoprotien (ZAG)

Objectives: The goal of the current study is to determine whether the β-adrenoreceptor (β-AR) plays a role in the anti-obesity and anti-diabetic effects of zinc-α2-glycoprotein (ZAG). Material and methods: This has been investigated in CHO-K1 cells transfected with the human β1-, β2-, β3-AR and in ob/ob mice. Cyclic AMP assays were carried out along with binding studies. Ob/ob mice were treated with ZAG and glucose transportation and insulin were examined in the presence or absence of propranolol. Results: ZAG bound to the β3-AR with higher affinity (Kd 46 ± 1 nM) than the β2-AR (Kd 71 ± 3 nM) while there was no binding to the β1-AR, and this correlated with the increases in cyclic AMP in CHO-K1 cells transfected with the various β-AR and treated with ZAG. Treatment of ob/ob mice with ZAG increased protein expression of β3-AR in gastrocnemius muscle, and in white and brown adipose tissues, but had no effect on expression of β1- and β2-AR. A reduction of body weight was seen and urinary glucose excretion, increase in body temperature, reduction in maximal plasma glucose and insulin levels in the oral glucose tolerance test, and stimulation of glucose transport into skeletal muscle and adipose tissue, were completely attenuated by the non-specific β-AR antagonist propranolol. Conclusion: The results suggest that the effects of ZAG on body weight and insulin sensitivity in ob/ob mice are manifested through a β-3AR, or possibly a β2-AR.     

Evaluation of raw-data-based and calculated electron density for contrast media with a dual-energy CT technique

ObjectivesThe aim of the current study is to evaluate the accuracy and the precision of raw-data-based relative electron density (RED_raw) and the calibration-based RED (RED_cal) at a range of low-RED to high-RED for tissue-equivalent phantom materials by comparing them with reference RED (RED_ref) and to present the difference of RED_raw and RED_cal for the contrast medium using dual-energy CT (DECT).MethodsThe RED_raw images were reconstructed by raw-data-based decomposition using DECT. For evaluation of the accuracy of the RED_raw, RED_ref was calculated for the tissue-equivalent phantom materials based on their specified density and elemental composition. The RED_cal images were calculated using three models: Lung-Bone model, Lung-Ti model and Lung-Ti (SEMAR) model which used single-energy metal artifact reduction (SEMAR). The difference between RED_raw and RED_cal was calculated.ResultsIn the titanium rod core, the deviations of RED_raw and RED_cal (Lung-Bone model, Lung-Ti model and Lung-Ti model with SEMAR) from RED_ref were 0.45%, 50.8%, 15.4% and 15.0%, respectively. The largest differences between RED_raw and RED_cal (Lung-Bone model, Lung-Ti model and Lung-Ti model with SEMAR) in the contrast medium phantom were 8.2%, ?23.7%, and 28.7%, respectively. However, the differences between RED_raw and RED_cal values were within 10% at 20 mg/ml. The standard deviation of the RED_raw was significantly smaller than the RED_cal with three models in the titanium and the materials that had low CT numbers.ConclusionThe RED_cal values could be affected by beam hardening artifacts and the RED_cal was less accurate than RED_raw for high-Z materials as titanium.Advances in knowledgeThe raw-data-based reconstruction method could reduce the beam hardening artifact compared with image-based reconstruction and increase the accuracy for the RED estimation in high-Z materials, such as titanium and iodinated contrast medium.     

Scintigraphy has the potential to replace thyroid stimulating hormone and ultrasonography in hyperthyroidism diagnosis

The value of thyroid scintigraphy in hyperthyroidism diagnosis has long been the subject of debate. Unresolved issue is whether scintigraphy should be performed routinely, selectively, or for all hyperthyroidism patients. So, this study is concerned with the evaluation of thyroid scintigraphy for identifying hyperthyroidism in comparison with thyroid stimulating hormone (TSH) and ultrasound. This is cross sectional study including convenient patients sample (n = 50, 15 males and 35 females) aged (20–50 years) with primary hyperthyroidism and were attending endocrine clinics at King Faisal Specialist Hospital and Research Centre. All patients performed clinical investigations (TSH, ultrasound and thyroid scintigraphy). Among these patients, 96%, 48/50, had positive findings for hyperthyroidism with thyroid SC (95% CI; 96.0–99.5%); 84%, 42/50, had positive findings for hyperthyroidism by US (95% CI; 70.9–92.8%); and 56%, 28/50, had positive findings for hyperthyroidism by TSH measurement (95% CI; 41.3.0–70.0%). There was very good agreement between scintigraphy diagnosis and ultrasonography (kappa score = 0.812 (P < 0.0001), 95% CI (0.77–0.85). In many cases, scintigraphy provides considerably more functioning and anatomic details than ultrasound. In conclusion, these findings bring forth practical aspects of thyroid scintigraphy utilization for hyperthyroidism. By combining functional and anatomical information in one step, scintigraphy provides non-invasive, simple, fast and cost effective hyperthyroidism diagnostic method and has the potential to replace TSH and ultrasonography in hyperthyroidism investigation.     

Human Misato regulates mitochondrial distribution and morphology

Misato of Drosophila melanogaster and Saccharomyces cerevisiae DML1 are conserved proteins having a homologous region with a part of the GTPase family that includes eukaryotic tubulin and prokaryotic FtsZ. We characterized human Misato sharing homology with Misato of D. melanogaster and S. cerevisiae DML1. Tissue distribution of Misato exhibited ubiquitous distribution. Subcellular localization of the protein studied using anti-Misato antibody suggested that it is localized to the mitochondria. Further experiments of fractionating mitochondria revealed that Misato was localized to the outer membrane. The transfection of Misato siRNA led to growth deficiencies compared with control siRNA transfected HeLa cells, and the Misato-depleted HeLa cells showed apoptotic nuclear fragmentation resulting in cell death. After silencing of Misato, the filamentous mitochondrial network disappeared and fragmented mitochondria were observed, indicating human Misato has a role in mitochondrial fusion. To examine the effects of overexpression, COS-7 cells were transfected with cDNA encoding EGFP-Misato. Its overexpression resulted in the formation of perinuclear aggregations of mitochondria in these cells. The Misato-overexpressing cells showed low viability and had no nuclei or a small and structurally unusual ones. These results indicated that human Misato has a role(s) in mitochondrial distribution and morphology and that its unregulated expression leads to cell death.