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Pheochromocytoma

Abstract

Pheochromocytomas are rare tumors originating in the adrenal medulla. They may be sporadic or in the context of a hereditary syndrome. A considerable number of pheochromocytomas carry germline or somatic gene mutations, which are inherited in the autosomal dominant way. All patients should undergo genetic testing. Symptoms are due to catecholamines over production or to a mass effect. Diagnosis is confirmed by raised plasma or urine metanephrines or normetanephrines. Radiology assists in the tumor location and any local invasion or metastasis. All the patients should have preoperative preparation with α-blockers and/or other medications to control hypertension, arrhythmia, and volume expansion. Surgery is the definitive treatment. Follow up should be life-long.

Open access
Sex and salt intake dependent renin-angiotensin plasticity in the liver of the rat

Abstract

Objective. Epidemiological studies confirm that hypertensive patients respond differently to renin-angiotensin system (RAS) inhibition depending on their gender. The aim of present work is to focus on sex-dependent differences in RAS regulation under conditions of increased salt intake.

Method. To investigate RAS, we measured the expression of angiotensinogen (Agt) mRNA, angiotensin receptor type 1 (AT1) mRNA and mitochondria assembly receptor (MasR) in the liver of rats under control conditions and after feeding with a salt diet (2% NaCl). In parallel, vascular endothelial growth factor A (VEGF-A) mRNA was analyzed.

Results. Regression analysis revealed sex-dependent differences in the correlation between mRNA expression of AT1 and that of Agt, MasR and VEGF-A in both groups. There was a significant negative correlation between AT1 and Agt mRNA expression in the male control group, but this correlation disappeared in males exposed to a salt diet. In females, AT1 and Agt expression correlated only in the group exposed to the salt diet. In control males, there was a borderline trend to correlation between AT1 and MasR mRNA expression. The correlation between AT1 and VEGF-A mRNA expression was significant only in the control females, however, after exposure to a salt diet, this correlation diminished.

Conclusions. We hypothesize that RAS components expression is compensated differently in males and females. The observed loss of compensatory relationships in RAS between AT1 and Agt and AT1 and MasR in male rats under a salt diet can contribute to the differences observed in human with hypertension associated with an unhealthy diet.

Open access
Spatial relationship between the c-Fos distribution and enkephalinergic, substance P, and tyrosine hydroxylase innervation fields after acute treatment with neuroleptics olanzapine, amisulpride, quetiapine, and aripiprazole in the rat septum

Abstract

Objective. The aim of the present study was to demonstrate the spatial relationship between the c-Fos immunoreactive cells elicited by an acute treatment with neuroleptics including amisulpride (AMI), olanzapine (OLA), quetiapine (QUE), and aripiprazole (ARI) and enkephalinergic (ENK), substance P (SP), and tyrosine hydroxylase (TH) innervation fields in the rat septum.

Methods. Male Sprague Dawley rats received a single injection of OLA (5 mg), ARI (10 mg), AMI (20 mg), QUE (15 mg/kg/b.w.). Ninety min after antipsychotics administration, the animals were transcardially perfused with a fixative and the brains cryocut into serial coronal sections of 35 µm thickness. The sections were processed for c-Fos staining using an avidin-biotin-peroxidase complex and visualized by nickel intensified diaminobenzidine to reach black endproduct. Afterwards, the sections were exposed to ENK, SP, and TH antibodies and the reaction product visualized by biotin-labeled fluorescent AlexaFluor 564 dye. The data were evaluated from the sections either simultaneously illuminated with fluorescent and transmission microscope beams or after merging the separately illuminated sections in the Adobe Photoshop 7.0 software.

Results. ENK, SP, and TH displayed characteristic spatial images formed by a dense accumulation of immunoreactive fibers and terminals on the both sides of the septum. A dense plexus of axons formed by ENK and SP immunopositive terminals were situated predominantly in the lateral, while TH ones more medial portion of the septum. QUE and AMI activated distinct amount of c-Fos expression in cells located within the SP-immunoreactive principal innervation field. The OLA effect on the c-Fos expression was very pronounced in the ventral TH-labeled principal innervation field including the space between the ENK field ventral portion and the dorsal margin of the accumbens nucleus shell. Generally, the occurrence of c-Fos cells in the ENK-immunoreactive principal innervation field, in comparison with the surrounding septal area, was less abundant after all of the four antipsychotics treatments.

Conclusion. The data of the present study indicate that ENK, SP, and TH innervation fields may influence separate populations of septal cells activated by AMI, OLA, QUE, and ARI and that each of these region-differently innervated cells may be associated with the functional heterogeneity of the individual lateral septal nuclei.

Open access
Ulmus minor bark hydro-alcoholic extract ameliorates histological parameters and testosterone level in an experimental model of PCOS rats

Abstract

Objective. Polycystic ovary syndrome (PCOS) is a common and multifactorial disease associated with female factor infertility. Ulmus minor bark (UMB) is one of the medicinal plants used in Persian folklore as a fertility enhancer. In the current study, we aimed to elucidate the effect of UMB hydro-alcoholic extract on histological parameters and testosterone condition in an experimental model of PCOS rats.

Methods. Thirty female rats were randomly divided into five groups: (1) control, (2) vehicle, (3) PCOS/50 mg [6 mg/kg dehydroepiandrosterone (DHEA) + 50 mg/kg UMB hydro-alcoholic extract], (4) PCOS/150 mg (6 mg/kg DHEA + 150 mg/kg UMB hydro-alcoholic extract), and (5) PCOS (6 mg/kg DHEA). All interventions were performed for 21 days. Afterwards, stereological analysis was done for determination of ovarian volume and follicle number. The serum level of testosterone was measured by ELISA kit.

Results. UMB hydro-alcoholic extract improved the total number of the corpus luteum in the treatment groups when compared to the PCOS group (p<0.05). PCOS/150 mg and PCOS/50 mg groups showed significantly lower total number of the primordial, primary, and secondary follicles as well as testosterone level compared to the PCOS group (p<0.05). The total number of antral follicles and volume of ovary did not differ significantly between groups.

Conclusion. UMB extract may be an effective and good alternative in improving PCOS histo-logical and testosterone disturbances although further studies are warranted to confirm the safety of UMB plant in human.

Open access
The Clinical Value of Red Blood Cell Distribution Width as a Prognosis Factor and Severity Marker in Sepsis and Septic Shock

Abstract

Red blood cell distribution width (RDW) is a hematological parameter usually measured with every complete blood count. Its place in daily practice is mainly in the differential diagnosis of anemia, but nowadays, researchers are focused on different approaches for the erythrocyte’s changes in function and morphology.

Sepsis and its most advanced form, septic shock, induces profound disturbances into organ system’s function and morphology. The red blood cells physiology and structure are directly and indirectly altered by these im balances produced in sepsis. RDW was studied in many diseases, like acute heart failure, acute stroke, inflammatory bowel diseases, chronic lung diseases and cancer, but also in sepsis. Its changes are seen to be mainly associated with prognosis. Higher values of RDW are correlated with mortality and severity of illnes in septic and all-cause critically ill patients. RDW was studied also as an independent variable in different predictive scores and some studies suggest it should be introduced in the scores use on a daily basis in critical care settings and emergency departments.

In this review we will focus on how RDW was associated with mortality and severity of illness in the recent literature, as an independent prognosis factor and as a component part in different predictive and severity scores.

Open access
Clozapine impact on FosB/ΔFosB expression in stress preconditioned rats: response to a novel stressor

Abstract

Objective. Prolonged treatment with neuroleptics has been shown to induce FosB/ΔFosB expression in several brain regions including the medial prefrontal cortex, dorsomedial and dorsolateral striatum, ventrolateral and dorsolateral septum, nucleus accumbens shell and core, and the hypothalamic paraventricular nucleus (PVN). Some of these regions are known to be also stress responsive. This study was designed to determine whether repeated clozapine (CLZ) administration for 7 consecutive days to Wistar rats may modify FosB/ΔFosB expression in the above-mentioned brain areas induced by acute stress or novel stressor that followed 13-day chronic mild stress preconditioning.

Methods. Following experimental groups were used: unstressed animals treated with vehicle/ CLZ for 7 days; 7-day vehicle/CLZ-treated animals on the last day exposed to acute stress – forced swimming (FSW); and animals preconditioned with stress for 13 days treated from the 8th day with vehicle/CLZ and on the 14th day exposed to novel stress – FSW.

Results. In the unstressed animals CLZ markedly increased FosB/ΔFosB immunoreactivity in the ventrolateral septum and PVN. FSW elevated FosB/ΔFosB expression in the medial prefrontal cortex, striatum, and septum. CLZ markedly potentiated the effect of the FSW on FosB/ΔFosB expression in the PVN, but suppressed it in the dorsomedial striatum. Novel stress with stress preconditioning increased FosB/ΔFosB immunoreactivity in the prefrontal cortex, striatum, ventrolateral septum, and the PVN. In the nucleus accumbens the effect of the novel stressor was potentiated by CLZ.

Conclusion. Our data indicate that CLZ may modulate the acute as well as novel stress effects on FosB/ΔFosB expression but its effect differs within the individual brain regions.

Open access
Cystic fibrosis related diabetes

Abstract

Cystic fibrosis related diabetes (CFRD) is a redoubtable complication associated to cystic fibrosis, with an increasing frequency, directly proportional to children life expectancy. Although this complication has similar features with DM type 1 and some with type 2, the evolution and even the response to insulin therapy is different. It is also possible that other factors to influence the CFRD clinical expression and subsequently the disease evolution. Since its 1t diagnosis was associated with more frequent pulmonary exacerbations and with the deterioration of the respiratory status, therefore CFRD must be early and correctly diagnosed and managed. The aim of this paper is to present an overview of the recent updates and recommendations regarding this important CF complication.

Open access
Differentiation of bone marrow derived mesenchymal stem cells into male germ-like cells in co-culture with testicular cells

Abstract

Objective. Stem cell therapy, specifically, pre-induction of mesenchymal stem cells toward male germ-like cells may be useful in patients with azoospermia. The aim of this study was to evaluate in vitro differentiation of mouse bone marrow-derived mesenchymal stem cells (BMSCs) into male germ-like cells by indirect co-culture with testicular cells in the presence of bone morphogenetic protein 4 (BMP4).

Methods. Experimental groups included: control (mouse BMSCs), treatment group-1 (BMSCs treated with BMP4), treatment group-2 (indirect co-culture of BMSCs with mouse testicular cells in the presence of BMP4) and treatment group-3 (indirect co-culture of BMSCs with testicular cells). BMSCs-derived male germ-like cells were evaluated by the expression of Dazl, and Stra8 using RT-qPCR.

Results. Stra8 gene expression was significantly increased in the treatment group-2 and Dazl gene was significantly increased in the treatment group-1 compared to other groups. In conclusion, indirect co-culturing of BMSCs with testicular cells and BMP4 leads to the differentiation of BMSCs into male germ-like cells which express specific male germ-like genes. Testicular cells released factors that contributed to the differentiation of BMSCs into male germ progenitor cells.

Conclusion. This study suggests that mesenchymal stem cells may be differentiated into male germ-like cells and therefore, may be a novel treatment option for men with azoospermia.

Open access
Enkephalinase activity is modified and correlates with fatty acids in frontal cortex depending on fish, olive or coconut oil used in the diet

Abstract

Objective. Enkephalins are neuropeptides involved in functions such as pain modulation and/ or cognitive processes. It has been reported that dietary fat modifies enkephalins in the brain. Since enkephalins are hydrolyzed by enkephalinases, the study of the influence of dietary fats, differing in their degree of saturation, on brain fatty acids content and enkephalinase activity is important to understand its regulatory role on neuropeptides under different type of diets.

Methods. We analyzed enkephalinase activity, assayed with alanine-β-naphthylamide as sub-strate, in frontal cortex of adult male rats fed diets supplemented with fish oil, olive oil or coconut oil, which markedly differed in the saturation of their fatty acids.

Results. Rats fed a diet enriched with coconut oil had lower soluble enkephalinase activity than the group fed olive oil (p<0.01) and fish oil (p<0.05) whereas rats fed a diet enriched with fish oil had lower membrane-bound enkephalinase activity than the group fed with olive (p<0.001) or coconut oil (p<0.05). Significant negative correlations were observed between certain fatty acids and enkephalinase activities in the groups fed with olive and coconut oils. No correlations were observed in the group fed with fish oil.

Conclusions. Dietary fat modifies enkephalinase activity in the frontal cortex depending on the degree of saturation of the used oil. It is postulated that the functions, in which enkephalins are involved, such as pain modulation or cognitive functions, may also be affected according to the type of oil used in the diet.

Open access
Evolution of Acinetobacter baumannii infections and antimicrobial resistance. A review

Abstract

The emergence of multi-drug resistant Acinetobacter spp involved in hospital-acquired infections, once considered an easily treatable pathogen, is troublesome and an immense burden for the modern medical systems worldwide. In the last 20 years the medical community recorded an increase in the incidence and severity of these infections as therapeutic means tend to be less and less effective on these strains. The ability of these bacteria to rapidly develop resistance to antimicrobial agents by continuously changing and adapting their mechanisms, their ability to survive for long periods of time in the hospital environment and the multitude of transmission possibilities raises serious issues regarding the management of these complex infections. The future lies in developing new and targeted methods for the early diagnosis of A. baumannii, as well as in the judicious use of antimicrobial drugs. This review details the evolution of the pathogenicity of this microorganism, together with the changes that appeared in resistance mechanisms and the advancements in molecular testing for the early detection of infection.

Open access