Sucrose sham feeding decreases accumbens norepinephrine in the rat

Noradrenergic projections from the dorsomedial medulla reach the shell of the nucleus accumbens (NAcc), a structure implicated in both reward and feeding behavior. Despite this relationship, the effect of food reward on accumbens norepinephrine (NE) remains uninvestigated. In the course of assessing dopamine (DA) in the NAcc during sucrose ingestion [0.03, 0.1, and 0.3 M; Am. J. Physiol., Regul. Integr. Comp. Physiol., 286 (2004) R31], we also analyzed NE in the microdialysis samples from 14 ad-libitum-fed male rats. In contrast to DA, which increased with sucrose concentration (+20-47%) during sham feeding, in the same animals, NE levels were reduced (approximately -20%), regardless of sucrose concentration. These results demonstrate a novel relationship between accumbens DA and NE during orosensory stimulation with a preferred nutrient.     

Analyzing the learning curves of a novice and an experienced urologist for transrectal magnetic resonance imaging-ultrasound fusion prostate biopsy

BackgroundThe aim of the current study was to evaluate and compare the learning curves of transrectal magnetic resonance imaging-ultrasound fusion biopsy for two urologists with different backgrounds (Operator 1: experienced, self-trained and Operator 2: novice, trained by a mentor/MRI reading courses).MethodsA cohort of 400 patients who underwent fusion prostate biopsy in our department was analyzed. The learning curves were assessed in terms of overall and clinically significant prostate cancer (PCa) detection rates, percentage of positive biopsy cores/targeted and the percentage of PCa tissue on positive targeted cores.ResultsIncreasing trends were observed for both urologists in terms of all biopsy outcomes during the study time. For the novice urologist, a significant increase was observed for overall PCa detection rate, but not for clinically significant disease (25.44%, P=0.04/15%, P=0.145). Operator 1 showed an increasing diagnosis yield of clinically significant disease up to 104 cases. Similar cancer detection rates were observed when comparing the first and last biopsies performed by both operators. Multivariate analysis adjusted for age, PSA, prostate volume, lesion diameter and PIRADS score showed an increase of PCa detection with 51% for every 52 biopsies performed (P=0.022).ConclusionsWhen starting with magnetic resonance imaging-ultrasound fusion prostate biopsy, mentoring and prostate magnetic resonance imaging reading training allow a novice urologist to demonstrate a good initial PCa detection rate. After about 52 cases, he reached a stable PCa and clinically significant PCa detection rate, that was similar to that of an experienced urologist.     

Why laparoscopic cholecystectomy today?

Traditional open cholecystectomy became the gold standard of surgical treatment for symptomatic gallstone disease during the last century. In spite of its good results, clinicians have been trying to establish effective nonsurgical methods of eliminating gallstones. Although oral, percutaneous, or retrograde litholysis can be used effectively for cholesterol stones, these represent only 10% of all gallstones. Moreover, intracorporeal lithotripsy is an invasive method, and while extracorporeal shock wave lithotripsy is a promising procedure, even after careful selection, only 70%–80% of the patients become stone-free within 1 year. In fact, none of the methods which leave the gallbladder intact are free of complications, and they are followed by 50% stone recurrence within 5 years. Since 1987, laparoscopic cholecystectomy has become the procedure of choice as it is safe and only minimally invasive. We believe that the laparoscopic technique is a promising way to the surgery of the future.     

Aluminum Perlite Syntactic Foams

This paper presents the usage of spark plasma sintering (SPS) as a method to obtain aluminum-expanded perlite syntactic foams with high porosity. In the test samples, fine aluminum powder with flaky shape particles was used as matrix material and natural, inorganic, granular, expanded perlite was used as a space holder to ensure high porosity (35–57%) and uniform structure. SPS was used to consolidate the specimens. The structures were characterized by scanning electron microscopy and compression tests. Energy absorption (W~7.49 MJ/m³) and energy absorption efficiency (EW < 90%) were also determined.     

Traumatic brain injury-induced cerebral microbleeds in the elderly

Traumatic brain injury (TBI) was shown to lead to the development of cerebral microbleeds (CMBs), which are associated with long term cognitive decline and gait disturbances in patients. The elderly is one of the most vulnerable parts of the population to suffer TBI. Importantly, ageing is known to exacerbate microvascular fragility and to promote the formation of CMBs. In this overview, the effect of ageing is discussed on the development and characteristics of TBI-related CMBs, with special emphasis on CMBs associated with mild TBI. Four cases of TBI-related CMBs are described to illustrate the concept that ageing exacerbates the deleterious microvascular effects of TBI and that similar brain trauma may induce more CMBs in old patients than in young ones. Recommendations are made for future prospective studies to establish the mechanistic effects of ageing on the formation of CMBs after TBI, and to determine long-term consequences of CMBs on clinically relevant outcome measures including cognitive performance, gait and balance function.

     

Type 2 diabetes: A side effect of the adaptation of neurons and fat cells to support increased cognitive performance

Type 2 diabetes is a serious disease that is affecting an increasing part of the population in most countries. A new hypothesis is presented in this paper about the underlying causes and mechanisms that lead to the development of this disease. It is proposed that the disease is the price that the organism pays for having improved cognitive performance that is achieved through increased level of neurite growth dynamics of neurons. The suggested mechanism of the disease development involves neural centres that deal with the sensing of fat and sugar levels in the blood and cerebro-spinal fluid, the regulation of the mobilisation of these resources in the body, the regulation of the storage of sugar and fat in the body, and the regulation of feeding behaviour. The key idea of the proposed mechanism is that the hypothesised resource mobilisation neural centre overestimates the resource needs of neurons and generates and inflated resource requesting signals. The paper discusses how short- and long-term equilibrium regulation of fat and sugar resources may emerge and how this regulation may get imbalanced leading to the emergence of type 2 diabetes in the animal or human. The paper proposes a number of experimental tests that can confirm or deny the validity of the hypothesis formulated here. Possible implications for development of new drugs aimed to prevent or reduce the negative impacts of type 2 diabetes are also discussed.     

Ross procedure using pulmonary autograft with a previous prosthetic patch

The case described is of a 7-year-old boy with recurrent long-segment left ventricular outflow tract obstruction. Due to previous pulmonary artery band stenosis and subsequent repair with a prosthetic patch, the pulmonary root was not intact. In this complicated Ross-Konno operation, the prosthetic patch was replaced with autologous tissue and the repaired pulmonary root was used successfully as an autograft.     

Stable intrachain and interchain complexes of neurofilament peptides: a putative link between Al3+ and Alzheimer disease.

The etiologic role of Al3+ in Alzheimer disease has been controversial. Circular dichroism (CD) spectroscopic studies on two synthetic fragments of human neurofilament protein mid-sized subunit (NF-M), NF-M13 (KSPVPKSPVEEKG) and NF-M17 (EEKGKSPVPKSPVEEKG), and their alanine-substituted and/or serine-phosphorylated derivatives were carried out in an attempt to find a molecular mechanism for the effect of Al3+ to induce aggregation of neuronal proteins or their catabolic fragments. Al3+ and Ca2+ ions were found to induce beta-pleated sheet formation in the phosphorylated fragments. The cation sensitivity depended on the length and charge distribution of the sequence and site of phosphorylation. Al3+-induced conformational changes were irreversible to citric acid chelation, whereas Ca(2+)-induced conformational changes were reversible with citric acid. Studies of the alanine derivatives demonstrated which residues affected Al3+ or Ca2+ binding. Peptides containing at least one free (nonphosphorylated) serine residue were shown to form an intramolecular Al3+ complex, rather than an intermolecular one. In the intramolecular (intrachain) complex, the ligand function of the deprotonated serine hydroxyl was delineated [(Al.pepH-1)-type complex]. Ca2+ ions did not show a tendency for intramolecular complexing. The potential role of Al3+ in Alzheimer disease tangle and plaque formation is strongly suggested.