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.     

The role of impulse oscillometry in detecting airway dysfunction in athletes

Background: Impulse oscillometry (IOS) has previously been proposed to provide greater sensitivity than spirometry when employed with indirect bronchoprovocation testing for the diagnosis of airway dysfunction in athletes. However, this recommendation is based on a highly selected population of symptomatic patients. Objective: To compare IOS, spirometry and respiratory symptoms following indirect bronchoprovocation in a screened cohort of athletes. Methods: One hundred and one recreational athletes were recruited. Respiratory symptoms were assessed via the Dyspnoea-12 questionnaire. Spirometry and IOS were performed pre and post a eucapnic voluntary hyperpnoea (EVH) challenge. Results: Ninety-four athletes completed the study. Sixteen athletes (17%) were positive for airway dysfunction based on spirometry (i.e. ≥10% fall in FEV₁) and 17 athletes (18%) based on IOS (i.e. ≥50% increase in R₅). Only nine athletes (10%) met both diagnostic thresholds. A poor relationship was observed between respiratory symptoms (i.e. Dyspnoea-12 score) and all spirometry and IOS variables. A direct relationship was observed between percentage change in R₅ (r?=?0.65), Z₅ (r?=?0.68), R_F (r?=?0.65), A_X (r?=?0.69) and the maximum fall in FEV₁ (ΔFEV₁max; p?<?0.001). A weak relationship was observed between R₂₀ (r?=?0.27), X₅ (r?=?0.37) and ΔFEV₁max (p?<?0.01). Conclusion: Impulse oscillometry and spirometry do not concur precisely following indirect bronchoprovocation. However, IOS detects additional cases of airway dysfunction in athletes and therefore may provide diagnostic value in this population. Further work is required to establish diagnostic thresholds and fully determine the place of IOS in screening athletes for airway dysfunction.     

The expanding spectrum of Mycobacterium avium complex-associated pulmonary disease

Nontuberculous mycobacteria (NTM) are increasingly recognized as important pulmonary pathogens. Mycobacterium avium intracellulare complex (MAC) causes most lung infections due to NTM. Patients with preexisting lung disease or immunodeficiency are at greatest risk for developing MAC infection. The majority of MAC pulmonary cases, however, occur in immunocompetent elderly women in association with nodular infiltrates and bronchiectasis. More recently, pulmonary disease has also been described in immunocompetent patients after exposure to MAC-contaminated hot tubs. We describe a case of aggressive MAC lung disease in a young immunocompetent female patient without preexisting lung disease whose clinical and pathologic characteristics do not fit into any of these categories and may represent a unique manifestation of MAC lung disease.     

Effect of vinpocetine on retrograde axoplasmic transport

Vinpocetine, a derivate of vincamine, is widely used in the clinical pharmacotherapy of cerebral circulatory diseases. Herewith we report on a novel effect of vinpocetine: inhibition of retrograde axoplasmic transport of nerve growth factor (NGF) in the peripheral nerve. Blockade of retrograde transport of NGF results in transganglionic degenerative atrophy (TDA) in the segmentally related ipsilateral superficial spinal dorsal horn, which is characterized by depletion of the marker enzymes fluoride-resistant acid phosphatase (FRAP) and thiamine monophosphatase (TMP). At the same time, pain-related neuropeptides such as substance P (SP) and calcitonin gene-related peptide (CGRP), are depleted from lamina I-III from the segmentally related, ipsitateral Rolando substance of the spinal cord. On the basis of these experiments it is suggested that vinpocetine may result in a locally restricted decrease of nociception, that might be useful in clinical treatment of intractable pain. Pilot self-experiments support this assumption.     

The origins of life -- the 'protein interaction world' hypothesis: protein interactions were the first form of self-reproducing life and nucleic acids evolved later as memory molecules

The 'protein interaction world' (PIW) hypothesis of the origins of life assumes that life emerged as a self-reproducing and expanding system of protein interactions. In mainstream molecular biology, 'replication' refers to the material copying of molecules such as nucleic acids. However, PIW is conceptualized as an abstract communication system constituted by the interactions between proteins, in which 'replication' happens at the level of self-reproduction of these interactions between proteins. Densely concentrated peptide interaction systems may have reproduced and expanded as 'protocell' vesicles surrounded by lipid bi-layer membranes. Protocells led to the emergence of proto-RNA molecules of greater chemical stability which served as chemically differentiated 'memories' of peptide interaction states, thereby facilitating the reproduction and expansion of protocells. Simplification-driven expansion led to the selection of biotic amino acids and the reduction of the typical RNA alphabet to the four usual bases (A, C, G and U). Dense interactions between RNA molecules led to the emergence of the RNA interaction subsystem of the cell, and to the emergence of 'memories' of RNA interactions in the form of DNA molecules with greater chemical stability. The expansion of DNA molecule interactions led to the dense clustering and encapsulation of DNA molecules within the cell nucleus. RNA molecules therefore serve as memories of protein interactions and DNA molecules are memories of RNA interactions. We believe that the PIW hypothesis is more evolutionarily plausible than the mainstream RNA world hypothesis, and has greater explanatory power.