Disorders of the brain-gut interaction and eating disorders

BACKGROUNDEating disorders (ED) involve both the nervous system and the gastrointestinal tract. A similar double involvement is also found in disorders of the brain-gut interaction (DGBI) and symptoms are sometimes similar.AIMTo find out where there is an association and a cause-effect relationship, we looked for the comorbidity of DGBI and ED.METHODSA systematic review was undertaken. A literature search was performed. Inclusion criteria for the articles retained for analysis were: Observational cohort population-based or hospital-based and case-control studies, examining the relationship between DGBI and ED. Exclusion criteria were: Studies written in other languages than English, abstracts, conference presentations, letters to the Editor and editorials. Selected papers by two independent investigators were critically evaluated and included in this review.RESULTSWe found 29 articles analyzing the relation between DGBI and ED comprising 13 articles on gastroparesis, 5 articles on functional dyspepsia, 7 articles about functional constipation and 4 articles on irritable bowel syndrome.CONCLUSIONThere is no evidence for a cause-effect relationship between DGBI and ED. Their common symptomatology requires correct identification and a tailored therapy of each disorder.     

Graphene nanoplatelets-sericin surface-modified Gum alloy for improved biological response

In this study a “Gum Metal” titanium-based alloy, Ti-31.7Nb-6.21Zr-1.4Fe-0.16O, was synthesized by melting and characterized in order to evaluate its potential for biomedical applications. The results showed that the newly developed alloy presents a very high strength, high plasticity and a low Young''s modulus relative to titanium alloys currently used in medicine. For further bone implant applications, the newly synthesized alloy was surface modified with graphene nanoplatelets (GNP), sericin (SS) and graphene nanoplatelets/sericine (GNP–SS) composite films via Matrix Assisted Pulsed Laser Evaporation (MAPLE) technique. The characterization of each specimen was monitored by scanning electron microscopy (SEM), atomic force microscopy (AFM), contact angle (CA) measurements, and Fourier Transform Infrared Spectroscopy (FTIR). The materials'' surface analyses suggested the successful coating of GNP, SS and GNP–SS onto the alloy surface. Additionally, the activities of pre-osteoblasts such as cell adhesion, cytoskeleton organization, cell proliferation and differentiation potentials exhibited on these substrates were investigated. Results showed that the GNP–SS-coated substrate significantly enhanced the growth and osteogenic differentiation of MC3T3-E1 cells when compared to bare and GNP-coated alloy. Collectively, the results show that GNP–SS surface-modified Gum alloy can modulate the bioactivity of the pre-osteoblasts holding promise for improved biological response in vivo.

GNP–SS functionalized Gum alloy exhibits superior bioactivity in inducing in vitro osteogenesis.     

Escitalopram versus placebo in the treatment of dysthymic disorder

Numerous studies have assessed the acute efficacy of antidepressants, including selective serotonin reuptake inhibitors, in treating dysthymic disorder; however, escitalopram, the S-enantiomer of citalopram, has not been studied. Thirty-six outpatients with Structured Clinical Interview for DSM-III-R-diagnosed dysthymic disorder, aged 23-65 years (mean±SD=44.7±11 years), were randomly assigned to double-blind escitalopram (maximum dose 20?mg/day) versus placebo for 12 weeks. Inclusion criteria included age 18-65 years and Hamilton Depression Rating Scale (HDRS) score≥12. We hypothesized that escitalopram would be superior to placebo in the HDRS-24 item total score at week 12. We also hypothesized the superiority of escitalopram over placebo for secondary measures, including the percentage of participants classified as responders and remitters, as well as social functioning (Social Adjustment Scale), clinical global impression-improvement, Global Assessment of Functioning Scale. Participants' baseline HDRS-24 averaged 23.4±5.9. Final HDRS-24 scores at last observation carried forward did not differ significantly between escitalopram-treated (mean±SD=10.88±5.83) and placebo-treated individuals (mean±SD=16.4±6.34) (F=2.82, degrees of freedom=1,32, P=0.10). Significant differences favoring active medication were found on the Social Adjustment Scale and the Clinical Global Impression Severity and Global Assessment of Functioning Scale, but not in the percentages of responders or remitters. A larger study sample or higher escitalopram dose may show more significant placebo-medication differences.     

Primary retroperitoneal tumors -- the experience in the Urological Clinic of the Central Military Hospital

Is a review of the 10 years experience in Urological Clinic of Central Military Hospital concerning the diagnosis and treatment of retroperitoneal tumors, containing personal conclusions about this relatively rare, heterogeneous entity.     

Digital-imaging microscopy analysis of calcium release from sarcoplasmic reticulum in single rat cardiac myocytes

Digital imaging microscopy of fura-2 fluorescence has allowed us to assess the dynamic patterns of local Ca increase in newly isolated rat myocardial cells. Of the myocytes bathed in a saline solution (1.8 mM Ca²⁺, 37°C, pH 7.4), 10%–20% exhibited local spontaneous contractions. The resting intracellular free calcium concentration ([Ca²⁺]_i) of these cells was 106±4nM versus 77±3 nM for non-contracting cells. The spontaneous contractile activity appeared to be closely related to internal spontaneous Ca waves that spread across the myoplasm (velocity 50 m/s, maximal Ca amplitude=195±11nM) along the major axis of the cells. Precise topographical examination of Ca wave propagation indicated a refractory period for internal Ca release. The occurrence of both the generation and propagation of spontaneous Ca increases appeared to be closely dependent on the extent of Ca loading of the cells. Most of our observations were in accordance with the assumption that local Ca overload of the sarcoplasmic reticulum (SR) is the main parameter involved in the spontaneous Ca-release phenomena. Using the same approach, the increase in internal Ca evoked by KCl (50 mM) addition was investigated, and compared with that seen during spontaneous activity. Total [Ca²⁺]_i increase induced by K⁺ depolarization involved three consecutive local Ca-release patterns: (a) a peripheral Ca enhancement that remained during the total [Ca²⁺]_i increase, (b) subsequent transversal local Ca increases occurring in Z-line regions, (c) longitudinal local Ca increases. In addition, a weak heterogeneous Ca distribution was detected in both peripheral and central parts of resting cardiac cells. Thus, the total Ca increase seemed to result consecutively from a peripheral Ca pool, from junctional SR and from longitudinal structures (possibly longitudinal SR).     

Cellular Motors for Molecular Manufacturing

Cells are composed of macromolecular structures of various sizes that act individually or collectively to maintain their viability and perform their function within the organism. This review focuses on one structure, the microtubule, and one of the motor proteins that move along it, conventional kinesin (kinesin 1). Recent work on the cellular functions of kinesins, such as the organization of microtubules during cellular division and the movement of the organelles and vesicles, offers insights into how biological motors might prove useful for organizing structures in engineered environments. Anat Rec, 290:1203–1212, 2007. © 2007 Wiley‐Liss, Inc.