Pre-synaptic and post-synaptic localization of EphA4 and EphB2 in adult mouse forebrain

The ephrin receptors EphA4 and EphB2 have been implicated in synaptogenesis and long-term potentiation in the cerebral cortex and hippocampus, where they are generally viewed as post-synaptic receptors. To determine the precise distribution of EphA4 and EphB2 in mature brain synapses, we used subcellular fractionation and electron microscopy to examine the adult mouse forebrain/midbrain. EphA4 and EphB2 were both enriched in microsomes and synaptosomes. In synaptosomes, they were present in the membrane and the synaptic vesicle fractions. While EphA4 was tightly associated with PSD-95-enriched post-synaptic density fractions, EphB2 was easily extracted with detergents. In contrast, both receptors were found in the pre-synaptic active zone fraction. By electron microscopy, EphA4 was mainly detected in axon terminals, whereas EphB2 was more frequently detected in large dendritic shafts, in the hippocampus and cerebral cortex. However, in the ventrobasal thalamus, EphB2 was detected most frequently in axon terminals and thin dendritic shafts. The localization of EphA4 and EphB2 in multiple compartments of neurons and synaptic junctions suggests that they interact with several distinct scaffolding proteins and play diverse roles at synapses.     

Prediction and prenosological diagnostics of heart diseases based on energy characteristics of acupuncture points and fuzzy logic

Many theories of reflexology use ancient concepts which do not coincide with the modern medical terminology of anatomy, physiology and biophysics. This substantially reduces the trust of physicians in reflexology methods. During this research, several mathematical models for the interaction of the internal and biological active points of meridian structures have been proposed. The analysis of these models allows the specification of a list of heart diseases for which reflex diagnostics and reflex therapy methods are most effective and also allows increasing the effectiveness of these procedures. It is shown that good results for the prediction and early diagnosis of diseases from the reaction energy of biologically active points (acupuncture points) are obtained using fuzzy logic decision making.     

Effects of the antidepressant fluoxetine on the subcellular localization of 5-HT1A receptors and SERT

Serotonin (5-HT) 5-HT(1A) autoreceptors (5-HT(1A)autoR) and the plasmalemmal 5-HT transporter (SERT) are key elements in the regulation of central 5-HT function and its responsiveness to antidepressant drugs. Previous immuno-electron microscopic studies in rats have demonstrated an internalization of 5-HT(1A)autoR upon acute administration of the selective agonist 8-OH-DPAT or the selective serotonin reuptake inhibitor antidepressant fluoxetine. Interestingly, it was subsequently shown in cats as well as in humans that this internalization is detectable by positron emission tomography (PET) imaging with the 5-HT(1A) radioligand [(18)F]MPPF. Further immunocytochemical studies also revealed that, after chronic fluoxetine treatment, the 5-HT(1A)autoR, although present in normal density on the plasma membrane of 5-HT cell bodies and dendrites, do not internalize when challenged with 8-OH-DPAT. Resensitization requires several weeks after discontinuation of the chronic fluoxetine treatment. In contrast, the SERT internalizes in both the cell bodies and axon terminals of 5-HT neurons after chronic but not acute fluoxetine treatment. Moreover, the total amount of SERT immunoreactivity is then reduced, suggesting that SERT is not only internalized, but also degraded in the course of the treatment. Ongoing and future investigations prompted by these finding are briefly outlined by way of conclusion.     

FRET analysis reveals a critical conformational change within the Na,K-ATPase alpha1 subunit N-terminus during GPCR-dependent endocytosis

Dopamine is a major regulator of sodium reabsorption in proximal tubule epithelia. It induces the endocytosis of plasma membrane Na,K-ATPase molecules, and this results in a reduced capacity of the cells to transport sodium. Dopamine induces the phosphorylation of Ser-18 in the alpha1-subunit of Na,K-ATPase. Fluorescence resonance energy transfer analysis of cells expressing YFP-alpha1 and beta1-CFP reveals that treatment of the cells with dopamine increases energy transfer between CFP and YFP. This is consistent with a protein conformational change that results in the N-terminal end of alpha1 moving closer to the internal face of the plasma membrane.     

Molecular characterization of Lebanese olive germplasm

Lebanon, an East Mediterranean country, does not have a comprehensive reference national olive collection. A report published 30 years ago indicated the presence of four Lebanese varieties, but the confusion regarding these varieties was discussed then and is still prevalent today hindering prospects for conserving and exploring the national germplasm. This study assessed the existing in situ diversity of old Lebanese olive groves using simple sequence repeat (SSR) and amplified fragment length polymorphisms (AFLP). Trees (140) were collected from 14 groves located in the four traditional olive areas. Analysis was based on 22 polymorphic alleles produced from six SSR primers, and on 135 polymorphic AFLP fragments. SSR and AFLP did not yield consistent results in terms of level of polymorphism, with SSR detecting higher variation than AFLP. On the other hand, both clustered trees based on geographic provenance. AFLP coefficient of similarity between trees ranged between 0.70 and 0.99 indicating the possible presence of varieties since some values fall within reported intervarietal ranges of 0.65 to 0.84. SSR unveiled the presence of nine different genotypes: four corresponding each to a provenance and five consisting of single trees characterized by the presence of less frequent alleles with an average of 0.33. Results also revealed a high incidence of clones greater than 90% in three of the four provenances. The findings of this study point for the need to plan for a sampling strategy that takes into consideration geographic provenances.     

Reproductive toxic impact of subchronic treatment with combined butylparaben and triclosan in weanling male rats

The effect of treatment with combined butylparaben and triclosan on male gonadal toxicity in weanling rats was investigated. All treated groups experienced atrophy in the ventral prostate and seminal vesicle, likewise significant depletion in the number and motility of sperm. Given individually or combined butylparaben and triclosan, significantly decreased testosterone, luteinizing hormone, and follicle‐stimulating hormone levels. Individual treatment with tested compounds caused significant elevation in the E₂ level, whereas combined treatment did not alter the E₂ level. Testicular DNA damage was recorded in all treated groups. Moreover, the testicular malondialdehyde level was significantly elevated, along with a significant decrease in catalase enzyme activity in all treated groups. Superoxide dismutase enzyme activity was significantly decreased in the butylparaben‐treated group, increased in the triclosan‐treated group, and nonsignificantly changed the butylparaben‐triclosan‐treated group. The combined treatment produced an endocrine disturbance with a concomitant induction of testicular oxidative stress, which may represent a common mechanism of endocrine disruptor‐mediated dysfunction.     

Non-dipping blood pressure in the metabolic syndrome among Arabs of the Oman family study

Objective: The objective was to examine the circadian changes in blood pressure and their relation to the metabolic syndrome and its components in Omani Arabs. Research Methods and Procedures: Ambulatory blood pressure (ABPM) was recorded in 1124 subjects from 5 large, extended, consanguineous, and young Arab pedigrees. According to the International Diabetes Federation's definition, 264 subjects had the metabolic syndrome, a prevalence of 23%. Subjects were defined as non‐dippers when their nocturnal systolic blood pressure (SBP) fell by <10% from daytime SBP. Results: Non‐dippers with the metabolic syndrome were 131 of 264 (50%), compared with 265 of 860 (31%) without the metabolic syndrome. Of the non‐dippers, 99 of 131 (76%) were females and 32 of 131 (24%) were males. Daytime and nighttime SBP and DBP and nighttime pulse pressure were significantly higher in non‐dipper subjects with the metabolic syndrome. The important determinants of a non‐dipping BP in this cohort were high BMI and high serum triglycerides. Discussion: We hypothesize that obesity and nocturnal volume‐dependent hypertension may be involved in the pathophysiology of non‐dipping in the metabolic syndrome. This study showed that non‐dipping BP was common in subjects with the metabolic syndrome. Higher 24‐hour blood pressure load may add to the indices of the overall cardiovascular burden already associated with the metabolic syndrome.     

Insertion-deletion polymorphism in the angiotensin-converting enzyme (ACE) gene among Sudanese, Somalis, Emiratis, and Omanis

The angiotensin-converting enzyme (ACE) gene in humans contains an insertion-deletion polymorphism in its intron 16. Because of its involvement with the renin-angiotensin system, the insertion-deletion polymorphism of the ACE gene has been widely investigated in different populations and in case-control studies. However, similar studies for Arab populations are limited in number. Therefore we have investigated the frequencies of the *I and *D alleles of the ACE gene among Sudanese, Somalis, and Arab nationals of the United Arab Emirates and Oman using previously described methods. Our data indicate a preponderance of the *D allele among the Arab and African populations studied (Sudanese, 0.64; Somalis, 0.73; Emiratis, 0.61; and Omanis, 0.71).     

Renal Cell Carcinoma Metastatic to the Liver: Early Response Assessment after Intraarterial Therapy Using 3D Quantitative Tumor Enhancement Analysis

PURPOSELiver metastases from renal cell carcinoma (RCC) are not uncommon in the course of disease. However, data about tumor response to intraarterial therapy (IAT) are scarce. This study assessed whether changes of enhancing tumor volume using quantitative European Association for the Study of the Liver (qEASL) on magnetic resonance imaging (MRI) and computed tomography (CT) can evaluate tumor response and predict overall survival (OS) early after therapy.RESULTSMean qEASL (cm³) decreased from 93.5 to 67.2 cm³ (P= .004) and mean qEASL (%) from 63.1% to 35.6% (P= .001). No significant changes were observed using other response criteria. qEASL was the only significant predictor of OS when used to stratify patients into responders and nonresponders with median OS of 31.9 versus 11.1 months (hazard ratio [HR], 0.43; 95% confidence interval [CI], 0.19-0.97; P= .042) for qEASL (cm³) and 29.9 versus 10.2 months (HR, 0.09; 95% CI, 0.01-0.74; P= .025) for qEASL (%).CONCLUSIONThree-dimensional (3D) quantitative tumor analysis is a reliable predictor of OS when assessing treatment response after IAT in patients with RCC metastatic to the liver. qEASL outperforms conventional non-3D methods and can be used as a surrogate marker for OS early after therapy.