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Plastic pollution represents a threat for biological communities and the ecological functions they provide in river ecosystems. In this study, we compared the microbial colonization of two plastics (biodegradable and non-biodegradable) and three natural substrata (leaves, sediment, and rocks) in two study sites of an urbanized watershed differing in their plastic-contamination degree (upstream and downstream). The density and diversity of bacterial, fungal, and algal communities, as well as the extracellular enzymatic activities β-glucosidase (GLU), N-acetyl-glucosaminidase (NAG), and phosphatase (PHO), were analysed in each substrata and site over a 4-week colonization experiment. Results showed higher microbial densities and enzymatic activities in leaves and sediment compared to plastics and rocks, probably due to the greater availability of organic carbon and nutrients in the former substrata. However, the microbial colonization of the two plastics was only different in the downstream site, where bacterial density and enzymatic activities were higher in the biodegradable plastic compared to the non-biodegradable plastic. Accordingly, the presence of biodegradable plastics would enhance the heterotrophic metabolism in plastic-polluted rivers., (© The Author(s) 2023. Published by Oxford University Press on behalf of FEMS.)

Brucellosis remains one of the most worldwide distributed zoonosis inflicting serious economical and human health problems in many areas of the world. The disease is caused by different species of the genus Brucella that have different tropisms towards different mammals being the most relevant for human health Brucella abortus, Brucella melitensis and Brucella suis that infect cows, goats/sheep, and swine respectively. For B. melitensis, considered the species with more zoonotic potential and highly aggressive for animals, only one vaccine is available to date in the market: Rev 1. This attenuated strain has the disadvantage that is has a very high residual virulence for animals and humans and, for this reason, it is applied by ocular instillation which is technically challenging in many productive settings. For this reason, the search for new vaccines for caprine and ovine brucellosis is an active topic of research. We describe here the construction of a novel highly attenuated vaccine strain (Bm Delta-pgm) that confers excellent levels of protection against B. melitensis in the mouse model of infection. This strain is a clean deletion of the phosphoglucomutase (pgm) gene that codes for a protein that catalyzes the conversion of glucose-6-P to glucose-1-P, which is used as a precursor for the biosynthesis of many polysaccharides, including the O-antigen of the lipopolysaccharide and cyclic beta glucans. Our results indicate that vaccination with Bm Delta-pgm induces a robust memory cellular immune response but no antibody production against the O-antigen. Cross protection experiments show that this new vaccine protects against B. abortus and B. suis raising the possibility that Bm Delta-pgm could be used as a universal vaccine for the most important Brucella species., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Biofilm growth is a significant source of contamination in the food industry. Enzymes are considered green countermeasures against biofilm formation in the food industry owing to their biodegradability and low toxicity. In this study, the synergistic effect of enzymes was studied against biofilm cleaning from hard surfaces. A mixed-microbial sample was sourced from a meat packaging line and biofilms were grown under high shear conditions on stainless steel and polyethylene surfaces. A model cleaning-in-place (CIP) parallel-plate flow chamber was used for firstly, the enzymatic cleaning and secondly, a disinfection step. The cleaning effectiveness was evaluated in response to different formulations containing non-foaming commercial surfactants among with amylase, protease and lipase at neutral pH. The formulation combining all three enzymes was the most effective, showing a synergy essential for the deformation of biofilm structure and consequently better disinfection of both material surfaces.

The peptidoglycan in Gram-negative bacteria is a dynamic structure in constant remodeling. This dynamism, achieved through synthesis and degradation, is essential because the peptidoglycan is necessary to maintain the structure of the cell but has to have enough plasticity to allow the transport and assembly of macromolecular complexes in the periplasm and outer membrane. In addition, this remodeling has to be coordinated with the division process. Among the multiple mechanisms bacteria have to degrade the peptidoglycan are the lytic transglycosidases, enzymes of the lysozyme family that cleave the glycan chains generating gaps in the mesh structure increasing its permeability. Because these enzymes can act as autolysins, their activity has to be tightly regulated, and one of the mechanisms bacteria have evolved is the synthesis of membrane bound or periplasmic inhibitors. In the present study, we identify a periplasmic lytic transglycosidase inhibitor (PhiA) in Brucella abortus and demonstrate that it inhibits the activity of SagA, a lytic transglycosidase we have previously shown is involved in the assembly of the type IV secretion system. A phiA deletion mutant results in a strain with the incapacity to synthesize a complete lipopolysaccharide but with a higher replication rate than the wild-type parental strain, suggesting a link between peptidoglycan remodeling and speed of multiplication., (Copyright © 2019 American Society for Microbiology.)

Background: The aim of this study was to compare OTSC® proctology and fistulectomy with primary sphincter reconstruction results as treatment strategies for anorectal low trans-sphincteric fistula., Methods: Between February 2012 and March 2013, patients affected by trans-sphincteric anal fistula were consecutively enrolled in the trial. Patients were randomized to receive fistulectomy with primary sphincter reconstruction or OTSC® Proctology. Demographic characteristics, comorbodities, previous anorectal treatments, and recurrent fistula data were acquired. Postoperative therapy data and pain and Wexner scores (30 and 60 dd) were acquired during follow-up. Furthermore, patients were contacted by telephone after six months, and were visited both one year and three years after surgery., Results: Thirty consecutive patients were included in the study. 15 patients underwent the OTSC® Proctology procedure and 15 underwent the standard fistulectomy. The success rate was 93.3% in the OTSC group. The mean postoperative stay was 1.3 days in the OTSC® patients and 3.6 days in the fistulectomy group patients. The mean medications required for complete healing was 3.2 in the OTSC group and 8.9 in the FIPS group., Conclusions: Our results suggest that OTSC® Proctology is an effective and safe treatment in achieving permanent closure of the internal fistula opening in selected patients, with excellent results in terms of pain, postoperative incontinence, healing time, and days of hospitalization.

Aim: The incidence of rectal cancer continues to rise. The functional results after complete Total Mesorectal Excision (TME) depend on the segment of colon used for reconstruction of colonic continuity and the form, the volume and the functional proprieties of the "neorectum". The aim of our study is evaluate the efficacy of our Modified Transverse Coloplasty Pouch (MTCP) after the treatment of low rectal cancer in terms of functional outcomes and quality of life., Patients and Methods: The study included 136 patients, underwent TME from January 2007 to December 2016 with diagnosis of extraperitoneal carcinoma of the rectum. The average distance of the tumor from the dentate line was 5.6 cm. Our follow-up protocol included functional outcome evaluation at 7th post-operative day (POD), 2nd month, and 6th month after the surgery., Results: All patients (M/F 84/52) underwent anterior rectal resection (TME) with MTCP. Frequency of bowel movements per 24 hours in the studied patients compared at 7th POD, 2 months, and 6 months. Since the first post-operative weeks there is an encouraging reduction of the frequency of bowel movements., Conclusion: Modified Transverse Coloplasty Pouch (MTCP) had better functional results and quality of life compared to patients with a Colonic J Pouch (CJP) and traditional Transverse Coloplasty Pouch (TCP).

Streams and rivers form dense networks, shape the Earth's surface and, in their sediments, provide an immensely large surface area for microbial growth. Biofilms dominate microbial life in streams and rivers, drive crucial ecosystem processes and contribute substantially to global biogeochemical fluxes. In turn, water flow and related deliveries of nutrients and organic matter to biofilms constitute major constraints on microbial life. In this Review, we describe the ecology and biogeochemistry of stream biofilms and highlight the influence of physical and ecological processes on their structure and function. Recent advances in the study of biofilm ecology may pave the way towards a mechanistic understanding of the effects of climate and environmental change on stream biofilms and the biogeochemistry of stream ecosystems.

Alcoholic cardiomyopathy represents a major clinical complication in chronic alcoholics. Previous studies from our laboratory indicate that acute and chronic exposure of liver cells to ethanol results in a major loss of cellular Mg(2+) as a result of alcohol oxidation. We investigated whether exposure to ethanol induces a similar Mg(2+) loss in cardiac cells. The results indicate that chronic exposure to a 6% ethanol-containing diet depleted cardiac myocytes of >25% of their cellular Mg(2+) content. Acute ethanol exposure, instead, induced a time- and dose-dependent manner of Mg(2+) extrusion from perfused hearts and collagenase-dispersed cardiac ventricular myocytes. Pretreatment with chlormethiazole prevented ethanol-induced Mg(2+) loss to a large extent, suggesting a role of ethanol oxidation via cyP4502E1 in the process. Magnesium extrusion across the sarcolemma occurred via the amiloride-inhibited Na(+)/Mg(2+) exchanger. Taken together, our data indicate that Mg(2+) extrusion also occurs in cardiac cells exposed to ethanol as a result of alcohol metabolism by cyP4502E1. The extrusion, which is mediated by the Na(+)/Mg(2+) exchanger, only occurs at doses of ethanol ≥0.1%, and depends on ethanol-induced decline in cellular ATP. The significance of Mg(2+) extrusion for the onset of alcoholic cardiomyopathy remains to be elucidated., (Copyright © 2015 Elsevier Inc. All rights reserved.)

Magnesium is required for many of the major organs to function and plays a crucial role in human and mammalian physiology. Magnesium is essential for the structure of bones and teeth, acts as a cofactor for more than 300 enzymes in the body, including binding to ATP for kinase reactions, and affects permeability of excitable membranes and neuromuscular transmission. Despite these essential roles, much is still unknown about magnesium physiology and homeostasis. Currently, nutritionists believe that the general population intakes insufficient magnesium daily through the diet. The effects of magnesium deficiency are, for the most part undetected, and simple, widespread assessments of magnesium intake remain unavailable for humans. Many of the patients admitted to hospitals or medical care facilities are unaware of their low magnesium levels. Moreover, because magnesium is predominantly an intracellular cation (>99%), serum magnesium levels remain a poor predictor of tissue magnesium content and availability. This review will discuss the effects of magnesium deficiency in various pathologies affecting the human population. The underlying causes for magnesium depletion in major physiological systems will be examined along with the involved signaling pathways and the main roles of magnesium homeostasis. Where possible (e.g. alcoholism), the implications of administering supplemental magnesium will be discussed. Ultimately, this review will advocate for the necessity of identifying easy and reproducible methods to assess serum and cellular magnesium levels and to identify magnesium deficiency in order to alleviate related pathological conditions.

Persistent mild to moderate hyperoxaluria (PMMH) is a common side effect of bariatric surgery. However, PMMH's role in the progression to calcium oxalate (CaOx) urolithiasis and its potential effects on non-renal tissues are unknown. To address these points, a trigger + maintenance (T + Mt) model of PMMH was developed in rats (Experiment 1). The trigger was an i.p. injection of PBS (TPBS) or 288 μmol sodium oxalate (T288). Maintenance (Mt) was given via minipumps dispensing PBS or 7.5-30 μmol potassium oxalate/day for 28 days. Urinary oxalate ranged from 7.7 ± 0.8 μmol/day for TPBS + MtPBS to 18.2 ± 1.5 μmol/day for T288 + Mt30 (p ≤ 0.0005). All rats receiving T288 developed CaOx nephrocalcinosis, and many developed 'stones'. This was also true for Mt doses that did not elevate urinary oxalate above that of TPBS + MtPBS (p > 0.1) and for rats that did not have a detectable surge in urinary oxalate post T288. When TPBS was administered, CaOx nephrocalcinosis did not develop regardless of the Mt dose even if urinary oxalate was elevated compared to TPBS + MtPBS (p ≤ 0.0005). One of the risks associated with PMMH is oxalate accumulation within tissues. Hence, in a second set of experiments (Experiment 2) different doses of oxalate (Mt0.05, Mt15, Mt30) labeled with (14)C-oxalate ((14)C-Ox) were administered by minipump for 13 days. Tissues were harvested and (14)C-Ox accumulation assessed by scintillation counting. (14)C-Ox accumulated in a dose dependent manner (p ≤ 0.004) in bone, kidney, muscle, liver, heart, kidney, lungs, spleen, and testis. All these tissues exhibited (14)C-Ox concentrations higher (p ≤ 0.05) than the plasma. Extrapolation of our results to patients suggests that PMMH patients should take extra care to avoid dietary-induced spikes in oxalate excretion to help prevent CaOx nephrocalcinosis or stone development. Monitoring for oxalate accumulation within tissues susceptible to damage by oxalate or CaOx crystals may also be required.

Problem: Magnesium sulfate (MgSO4 ) exposure reduces the risk of cerebral palsy. As neonatal inflammatory cytokine levels strongly correlate with neurologic outcome, we hypothesize that MgSO4 decreases inflammatory cytokine production., Method of Study: We assessed the effect of MgSO4 on cellular magnesium levels, cytokine production, and release within THP-1 and cord blood mononuclear cells., Results: MgSO4 exposure increased intracellular magnesium levels, reducing the frequency of THP-1 cells producing IL-1β, IL-8, and TNF-α following LPS stimulation. Significant reductions in the frequency of neonatal monocytes producing TNF-α (48%) and IL-6 (37%) were seen following LPS stimulation, and MgSO4 also significantly decreased the frequency of monocytes producing TNF-α (35%) under basal conditions. Decreased cytokine production was confirmed via ELISA, demonstrating a sustained effect and dose response. Magnesium also reduced cytokine production following stimulation with TLR ligands representing obstetrical infections (group B Streptococcus and Mycoplasma) and in preterm neonatal monocytes., Conclusion: MgSO4 increases intracellular magnesium, reducing inflammatory cytokine production and release, potentially elucidating the mechanism by which MgSO4 prevents cerebral palsy, eclampsia, and preterm birth., (© 2013 John Wiley & Sons Ltd.)

Magnesium, the second most abundant cation within the cell, plays an important role in numerous biological functions. Experimental evidence indicates that mammalian cells tightly regulate cellular magnesium ion content through specific mechanisms controlling Mg(2+) entry and efflux across the cell membrane and the membrane of various cellular organelles as well as intracellular Mg(2+) buffering under resting conditions and following hormonal and metabolic stimuli. This chapter will provide an assessment of the various mechanisms controlling cellular Mg(2+) homeostasis and transport, and the implications changes in cellular Mg(2+) content play under physiological and pathological conditions.

Mammalian cells tightly regulate cellular Mg(2+) content through a variety of transport and buffering mechanisms under the control of various hormones and cellular second messengers. The effect of these hormones and agents results in dynamic changes in the total content of Mg(2+) being transported across the cell membrane and redistributed within cellular compartments. The importance of maintaining proper cellular Mg(2+) content optimal for the activity of various cellular enzymes and metabolic cycles is underscored by the evidence that several diseases are characterized by a loss of Mg(2+) within specific tissues as a result of defective transport, hormonal stimulation, or metabolic impairment. This chapter will review the key mechanisms regulating cellular Mg(2+) homeostasis and their impairments under the most common diseases associated with Mg(2+) loss or deficiency.

Magnesium (Mg(2+)) is used pharmacologically to sedate specific forms of arrhythmias. Administration of pharmacological doses of catecholamine or adrenergic receptor agonists often results in arrhythmias onset. Results from the present study indicate that stimulation of cardiac adrenergic receptors elicits an extrusion of cellular Mg(2+) into the extracellular space. This effect occurs in both perfused hearts and isolated cells within 5-6 min following either β- or α1- adrenergic receptor stimulation, and is prevented by specific adrenergic receptors antagonists. Sequential stimulation of the two classes of adrenergic receptor results in a larger mobilization of cellular Mg(2+) provided that the two agonists are administered together or within 1-2 min from each other. A longer delay in administering the second stimulus results in the abolishment of Mg(2+) extrusion. Hence, these data suggest that the stimulation of β- and α1-adrenergic receptors mobilizes Mg(2+) from two distinct cellular pools, and that Mg(2+) loss from either pool triggers a Mg(2+) redistribution within the cardiac myocyte. At the sarcolemmal level, Mg(2+) extrusion occurs through a Na(+)/Mg(2+) exchange mechanism phosphorylated by cAMP. Administration of quinidine, a patent anti-arrhythmic agent, blocks Na(+) transport in a non-specific manner and prevents Mg(2+) extrusion. Taken together, these data indicate that catecholamine administration induces dynamic changes in total and compartmentalized Mg(2+) pools within the cardiac myocytes, and suggest that prevention of Mg(2+) extrusion and redistribution may be an integral component of the effectiveness of quinidine and possibly other cardiac antiarrhythmic agents. Confirmation of this possibility by future experimental and clinical studies might result in new patents of these compounds as Mg(2+) preserving agents.

MgSO(4) exposure before preterm birth is neuroprotective, reducing the risk of cerebral palsy and major motor dysfunction. Neonatal inflammatory cytokine levels correlate with neurologic outcome, leading us to assess the effect of MgSO(4) on cytokine production in humans. We found reduced maternal TNF-α and IL-6 production following in vivo MgSO(4) treatment. Short-term exposure to a clinically effective MgSO(4) concentration in vitro substantially reduced the frequency of neonatal monocytes producing TNF-α and IL-6 under constitutive and TLR-stimulated conditions, decreasing cytokine gene and protein expression, without influencing cell viability or phagocytic function. In summary, MgSO(4) reduced cytokine production in intrapartum women, term and preterm neonates, demonstrating effectiveness in those at risk for inflammation-associated adverse perinatal outcomes. By probing the mechanism of decreased cytokine production, we found that the immunomodulatory effect was mediated by magnesium and not the sulfate moiety, and it was reversible. Cellular magnesium content increased rapidly upon MgSO(4) exposure, and reduced cytokine production occurred following stimulation with different TLR ligands as well as when magnesium was added after TLR stimulation, strongly suggesting that magnesium acts intracellularly. Magnesium increased basal IĸBα levels, and upon TLR stimulation was associated with reduced NF-κB activation and nuclear localization. These findings establish a new paradigm for innate immunoregulation, whereby magnesium plays a critical regulatory role in NF-κB activation, cytokine production, and disease pathogenesis.

Aim: Gastrointestinal stromal tumor (GIST) is the most common mesenchymal tumor of the gastrointestinal tract. Surgery remains the elective treatment. We retrospectively compared two group of patients, who underwent surgery for GIST before and after Imatinib advent in order to analyze the recurrence and survival rate., Methods: Two patient groups who underwent surgery for GIST, from January 1997 to December 2002 (Pre-Imatinib group) and from January 2003 to December 2008 (Post-Imatinib group) were compared. Patients were evaluated on the base of gender, age, clinical manifestations, primary location and metastasis positivity, tumor size, mitotic index, immunoreactivity for CD117 and the outcome, including date of death., Results: In the Pre-IM group only one patient died for prostate cancer, 12 months after operation, the other died because of GIST with a 24.6 months of median survival rate (range 15-51). In the remaining 12 patients the median follow up period was 55 months (range 6-152 months). In the Post-IM group the mean follow up was 50.7 months (range 26-74) and they are still being assessed for oncological as well as surgical treatment., Conclusion: Early diagnosis and radical resection remain the standard of cure for GISTs. To date, the use of Imatinib lead to its utilization as adjuvant and neo-adjuvant therapy in adults. Our experience suggests that there is a correlation between the mutational status of KIT and clinical outcome. These aspects should be explored for targeted therapy that can effectively combine biological therapy to surgery.

Purpose: Haemorrhoidal disease is one of the most common anorectal disorders. The aim of this study is to compare the results, over the last 10 years, of stapled haemorrhoidopexy (SH) with those of standard Milligan-Morgan haemorrhoidectomy (M&M). Furthermore, we discuss the proper indications for each technique in terms of the lowest rate of complications and long-term results., Methods: Three hundred forty-three patients with different degrees of symptomatic haemorrhoids underwent SH or M&M from January 2005 to December 2007. Patients were divided into two groups, age and sex matched. The administration of painkillers drugs, antibiotics and laxatives, complication symptoms and hospital stay in all the patients were recorded after surgical treatment., Results: The mean operative time was shorter in the stapled group compared to that in the open group (31 min versus 40 min). Postoperative pain, hospital stay and return to full activity were shorter in the stapled group. There was a significant difference in the wound healing time between the two groups. We noticed a higher rate of recurrence in patients treated with stapled haemorrhoidectomy for fourth-degree haemorrhoids., Conclusions: According to our experience, the Longo technique is indicated for the treatment of haemorrhoids of second- and third degree. In the latter grades of prolapse, the Milligan-Morgan haemorrhoidectomy can also be applied with good outcomes. We believe that, in case of irreducible prolapse, the M&M is to be preferred. However, operative management varies according to surgeon's interest and is tailored to meet the individual patient's need.

Magnesium, the second most abundant cellular cation after potassium, is essential to regulate numerous cellular functions and enzymes, including ion channels, metabolic cycles, and signaling pathways, as attested by more than 1000 entries in the literature. Despite significant recent progress, however, our understanding of how cells regulate Mg(2+) homeostasis and transport still remains incomplete. For example, the occurrence of major fluxes of Mg(2+) in either direction across the plasma membrane of mammalian cells following metabolic or hormonal stimuli has been extensively documented. Yet, the mechanisms ultimately responsible for magnesium extrusion across the cell membrane have not been cloned. Even less is known about the regulation in cellular organelles. The present review is aimed at providing the reader with a comprehensive and up-to-date understanding of the mechanisms enacted by eukaryotic cells to regulate cellular Mg(2+) homeostasis and how these mechanisms are altered under specific pathological conditions., (Copyright © 2011 Elsevier Inc. All rights reserved.)

River biofilms that grow on wet benthic surface are mainly composed of bacteria, algae, cyanobacteria and protozoa embedded in a polysaccharide matrix. The effects of increased river water temperature on biofilm formation were investigated. A laboratory experiment was designed employing two temperatures (11.1-13.2°C, night-day; 14.7-16.0°C, night-day) and two nutrient levels (0.054 mg P l(-1), 0.75 mg N l(-1); 0.54 mg P l(-1), 7.5 mg N l(-1)). Biofilm formation at the higher temperature was faster, while the biomass of the mature biofilm was mainly determined by nutrient availability. The specific response of the three microbial groups that colonized the substrata (algae, bacteria and ciliates) was modulated by interactions between them. The greater bacterial growth rate and earlier bacterial colonization at the higher temperature and higher nutrient status was not translated into the accrual of higher bacterial biomass. This may result from ciliates grazing on the bacteria, as shown by an earlier increase in peritrichia at higher temperatures, and especially at high nutrient conditions. Temperature and ciliate grazing might determine the growth of a distinctive bacterial community under warming conditions. Warmer conditions also produced a thicker biofilm, while functional responses were much less evident (increases in the heterotrophic utilization of polysaccharides and peptides, but no increase in primary production and respiration). Increasing the temperature of river water might lead to faster biofilm recolonization after disturbances, with a distinct biofilm community structure that might affect the trophic web. Warming effects would be expected to be more relevant under eutrophic conditions.

Vascular calcification is a multifaceted process involving gain of calcification inducers and loss of calcification inhibitors. One such inhibitor is inorganic pyrophosphate (PP(i)), and regulated generation and homeostasis of extracellular PP(i) is a critical determinant of soft-tissue mineralization. We recently described an autocrine mechanism of extracellular PP(i) generation in cultured rat aortic vascular smooth muscle cells (VSMC) that involves both ATP release coupled to the ectophosphodiesterase/pyrophosphatase ENPP1 and efflux of intracellular PP(i) mediated or regulated by the plasma membrane protein ANK. We now report that increased cAMP signaling and elevated extracellular inorganic phosphate (P(i)) act synergistically to induce calcification of these VSMC that is correlated with progressive reduction in ability to accumulate extracellular PP(i). Attenuated PP(i) accumulation was mediated in part by cAMP-dependent decrease in ANK expression coordinated with cAMP-dependent increase in expression of TNAP, the tissue nonselective alkaline phosphatase that degrades PP(i). Stimulation of cAMP signaling did not alter ATP release or ENPP1 expression, and the cAMP-induced changes in ANK and TNAP expression were not sufficient to induce calcification. Elevated extracellular P(i) alone elicited only minor calcification and no significant changes in ANK, TNAP, or ENPP1. In contrast, combined with a cAMP stimulus, elevated P(i) induced decreases in the ATP release pathway(s) that supports ENPP1 activity; this resulted in markedly reduced rates of PP(i) accumulation that facilitated robust calcification. Calcified VSMC were characterized by maintained expression of multiple SMC differentiation marker proteins including smooth muscle (SM) alpha-actin, SM22alpha, and calponin. Notably, addition of exogenous ATP (or PP(i) per se) rescued cAMP + phosphate-treated VSMC cultures from progression to the calcified state. These observations support a model in which extracellular PP(i) generation mediated by both ANK- and ATP release-dependent mechanisms serves as a critical regulator of VSMC calcification.

Extracellular inorganic pyrophosphate (PP(i)) is a potent suppressor of physiological calcification in bone and pathological calcification in blood vessels. Ectonucleotide pyrophosphatase/phosphodiesterases (eNPPs) generate PP(i) via the hydrolysis of ATP released into extracellular compartments by poorly understood mechanisms. Here we report that cultured vascular smooth muscle cells (VSMC) from rat aorta generate extracellular PP(i) via an autocrine mechanism that involves ATP release tightly coupled to eNPP activity. The nucleotide analog beta,gamma-methylene ATP (MeATP or AMPPCP) was used to selectively suppress ATP metabolism by eNPPs but not the CD39-type ecto-ATPases. In the absence of MeATP, VSMC generated extracellular PP(i) to accumulate >or=600 nM within 2 h while steadily maintaining extracellular ATP at 1 nM. Conversely, the presence of MeATP completely suppressed PP(i) accumulation while increasing ATP accumulation. Probenecid, which inhibits PP(i) efflux dependent on ANK, a putative PP(i) transporter or transport regulator, reduced extracellular PP(i) accumulation by approximately twofold. This indicates that autocrine ATP release coupled to eNPP activity comprises >or=50% of the extracellular PP(i)-generating capacity of VSMC. The accumulation of extracellular PP(i) and ATP was markedly attenuated by reduced temperature but was insensitive to brefeldin A, which suppresses constitutive exocytosis of Golgi-derived secretory vesicles. The magnitude of extracellular PP(i) accumulation in VSMC cultures increased with time postplating, suggesting that ATP release coupled to PP(i) generation is upregulated as cultured VSMC undergo contact-inhibition of proliferation or deposit extracellular matrix.

Clinical and experimental evidence indicates alcohol consumption as one of the major causes of magnesium loss from several tissues. As a result of this loss, serum magnesium tends to decrease while urinary magnesium excretion increases 2-3 fold. Experimental data confirm that chronic consumption of 6% ethanol in the Lieber De-Carli diet for 3 weeks results in a marked decrease in total tissue magnesium content in rats. This decrease affects brain, liver and all skeletal muscle, including heart, to a varying extent. While a full picture of the implications of magnesium loss in these tissues is still lacking, it is becoming progressively clear that magnesium loss affects energy production, protein synthesis, cell cycle, and specific functions in the various organs affected. In addition, as magnesium regulated cytokine production and secretion, especially in macrophages and leukocytes, a major role of magnesium deficiency in alcohol-induced inflammatory processes can be envisioned. Considering all these various aspects together, it becomes apparent that magnesium loss may represent a predisposing factor to the onset of alcohol-induced pathologies including brain stroke, sarcopenia, cardiomyopathy, steatohepatitis and cirrhosis. The present review will attempt to clarify some of the mechanisms by which ethanol impairs magnesium transport and homeostasis in brain, brain vasculature, skeletal muscle, heart and liver cells, as a first step towards more mechanistic studies aimed at relating magnesium loss with the incurrence of short- and long-term ethanol-induced complications in these organs.

Background: In the last ten years the introduction of various open mesh and laparoscopic techniques has increased the interest in inguinal hernia surgery. Anyway controversy persists about the most effective inguinal hernia repair. The aim of this study was to compare the results of open mesh technique and laparoscopic transabdominal preperitoneal (TAPP) repair for inguinal hernia., Patients and Methods: We considered 584 patients, 532 man and 52 woman, between 19 and 86 years: 332 (56.8%) had open mesh repair and 252 (43.2%) laparoscopic TAPP repair of groin hernia. Operative time, complications, recurrences and time to normal activities were recorded in both groups (range follow-up 1-10 years)., Results: The median operative time was 71 min for open group and 92 min for TAPP group. No intraoperative complications were observed. Postoperative complication rate was 4,5% in patients open group and 3% in TAPP group. The recurrence rate was less than 1% in both groups (0,6% for open repair and 0,4% for laparoscopic repair). Significant difference was observed in the median time to return to normal activities: 9,8 days in TAPP group versus 13,4 days in open approach., Conclusions: Our experience confirmed the safety and effectiveness of laparoscopic transabdominal preperitoneal (TAPP) approach to inguinal hernia repair as excellent alternative to conventional surgery. The reduction of operative time, complications and recurrences is correlated to the surgeon's experience and learning curve.

The goal of this study was to evaluate the complication rate of reoperative thyroid surgery and to find out the way to minimize the morbidity associated with it. We reviewed our experience in 622 patients, who underwent thyroid operation from January 2000 to September 2007. Among these ones, 76 were the patients who underwent reoperative thyroid surgery. Prior surgery in the 76 reoperations was: nucleo-resection in 9 pts (12.9%), lobectomy in 43 pts (55.5%), lobectomy+isthmectomy in 7 pts (9.3%), subtotal thyroidectomy in 17 pts (22.2%). Histologic examination revealed: benign lesions in 67 pts (88.15%), papillary cancer in 4 pts (5.26%), follicular cancer in 2 pts (2.63%), follicular adenoma in 1 pt (1.32%) and Hashimoto thyroiditis in 2 pts (2.63%). Complications included: section of recurrent laryngeal nerve, that was reconstructed in the same operation, and bilateral palsy of the recurrent laryngeal nerve so that was necessary to make a tracheotomy. One of the patient at the first thyroid surgery had monolateral palsy of the recurrent laryngeal nerve with dyspnoea and dysphonia. Temporary hypoparathyroidism (Ca<8 mg/dl) occurred in 47.3% of the patients, who underwent reoperative thyroid surgery and in 45.2% of the patients, who underwent prior thyroid surgery. Conclusions. This study documents that reoperative thyroid surgery can be performed with little morbidity to the patient if precise operative rules are respected.

Background: The recommended NKF-K/DOQI'99 ranges for Ca, P and PTH in dialysis seem advisable also for patients previously submitted to parathyroidectomy; however no paper addresses, specifically in this condition, to what extent optimal values are targeted in the short and long term after surgery., Methods: We checked serum Ca, P and PTH basally and after 1 month and 1, 3 and 5 years since surgery, in 77 dialysis subjects who received parathyroidectomy in our hospital., Results: Immediately after surgery all biochemical para- meters dropped, but afterwards Ca showed a tendency to increase progressively in the long term (p <.0006), P increased mostly within one year (p <.01), and PTH increased similarly to Ca (p <.003), but with mean values always in the lower than desired range. The estimated percentage of patients at target during the follow-up was maximal for P (values between 65 and 76%), lower for Ca (zenith of 43% after 1 month but declining down to 14% after 5 years) and minimal for PTH (invariably <10%). Persistence within the ranges (at least on two consecutive checks) was 21% after one month for Ca, with a tendency to reduction; 41% for P, with a tendency to average roughly 30%, and practically zero for PTH. Neither type of surgery (total or subtotal) nor vitamin D therapy were associated with the low values of PTH observed., Conclusions: We conclude that parathyroid surgery does not represent an optimal therapeutic tool for targeting the recommended ranges for Ca, P and PTH. In particular, too low PTH values are frequently obtained, whose clinical effects deserve further studies. The possibility of a time dependent risk for recurrence is confirmed.

The incidence of calcium oxalate nephrolithiasis in the US has been increasing throughout the past three decades. Biopsy studies show that both calcium oxalate nephrolithiasis and nephrocalcinosis probably occur by different mechanisms in different subsets of patients. Before more-effective medical therapies can be developed for these conditions, we must understand the mechanisms governing the transport and excretion of oxalate and the interactions of the ion in general and renal physiology. Blood oxalate derives from diet, degradation of ascorbate, and production by the liver and erythrocytes. In mammals, oxalate is a terminal metabolite that must be excreted or sequestered. The kidneys are the primary route of excretion and the site of oxalate's only known function. Oxalate stimulates the uptake of chloride, water, and sodium by the proximal tubule through the exchange of oxalate for sulfate or chloride via the solute carrier SLC26A6. Fecal excretion of oxalate is stimulated by hyperoxalemia in rodents, but no similar phenomenon has been observed in humans. Studies in which rats were treated with (14)C-oxalate have shown that less than 2% of a chronic oxalate load accumulates in the internal organs, plasma, and skeleton. These studies have also demonstrated that there is interindividual variability in the accumulation of oxalate, especially by the kidney. This Review summarizes the transport and function of oxalate in mammalian physiology and the ion's potential roles in nephrolithiasis and nephrocalcinosis.

Cardiac ventricular myocytes extrude a sizeable amount of their total Mg(2+) content upon stimulation by beta-adrenergic agonists. This extrusion occurs within a few minutes from the application of the agonist, suggesting the operation of rapid and abundantly represented Mg(2+) transport mechanisms in the cardiac sarcolemma. The present study was aimed at characterizing the operation of these transport mechanisms under well defined conditions. Male Sprague-Dawley rats were used to purify a biochemical standardized preparation of sealed rat cardiac sarcolemmal vesicles. This experimental model has the advantage that trans-sarcolemmal cation transport can be studied under specific extra- and intra-vesicular ionic conditions, in the absence of intracellular organelles, and buffering or signaling components. Magnesium ion (Mg(2+)) transport was assessed by atomic absorbance spectrophotometry. The results reported here indicate that: (1) sarcolemma vesicles retained trapped intravesicular Mg(2+) in the absence of extravesicular counter-ions; (2) the addition of Na(+) or Ca(2+) induced a rapid and concentration-dependent Mg(2+) extrusion from the vesicles; (3) co-addition of maximal concentrations of Na(+) and Ca(2+) resulted in an additive Mg(2+) extrusion; (4) Mg(2+ )extrusion was blocked by addition of amiloride or imipramine; (5) pre-treatment of sarcolemma vesicles with alkaline phosphatase at the time of preparation completely abolished Na(+)- but not Ca(2+)-induced Mg(2+) extrusion; (6) Na(+)-dependent Mg(2+) transport could be restored by stimulating vesicles loaded with protein kinase A catalytic subunit and ATP with membrane-permeant cyclic-AMP analog; (7) extra-vesicular Mg(2+) could be accumulated in exchange for intravesicular Na(+) via a mechanism inhibited by amiloride or alkaline phosphatase treatment; (8) Mg(2+) accumulation could be restored via cAMP/protein kinase A protocol. Overall, these data provide compelling evidence for the operation of distinct Na(+)- and Ca(2+)-dependent Mg(2+) extrusion mechanisms in sarcolemma vesicles. The Na(+)-dependent mechanism appears to be specifically activated via protein kinase A/cAMP-dependent phosphorylation process, and can operate in either direction based upon the cation concentration gradient across the sarcolemma. The Ca(2+)-dependent mechanism, instead, only mediates Mg(2+) extrusion in a cAMP-independent manner.

Background: Intraoperative parathyroid hormone (iPTH) assay (QPTH) in combination with preoperative localization, permits a less invasive operative approach in the treatment of hyperparathyroidism. A 50% reduction of the intraoperative PTH level, mesured within 15 minutes with an immunochemestry system of III generation (ICMA), shows the completeness of the hypersecretive tissues surgical removal., Patients and Methods: From June 2003 to December 2005 a series of 39 patients underwent target parathyroidectomy with intraoperative parathyroid hormone assay for parathyroid disease. Intraoperative PTH was measured before, 5-10 and 20 minutes after parathyroidectomy. 79.5% of patients had secondary hyperparathyroidism, 29.5% had primary disease. In 38 patients (97,4%) the intraoperative PTH levels declined more than 70% and in only one patient (2,6%) intraoperative PTH levels declined less than 50%., Results and Conclusions: QPTH has deeply modified the surgical approach to the treatment of hyperparathyroidism. Intraoperative measurement of iPTH is useful in prediction the complete removal of all parathyroid tissue after surgery for parathyroid disease, thus avoiding persistence or recurrence of disease and surgical failures. In well-studied cases QPTH can be considered a valid alternative to the intraoperative hystological examination.

Mammalian cells tightly regulate cellular Mg2+ content despite undergoing a variety of hormonal and metabolic stimulatory conditions. Evidence from several laboratories indicates that stimulatory conditions that increase cellular cAMP level result in a major mobilization of Mg2+ from cells and tissues into the bloodstream. Conversely, hormones or agents that decrease cAMP level or activate protein kinase C signaling induce a major accumulation of Mg2+ into the tissues. These Mg2+ fluxes are quite large and fast suggesting the operation of powerful transport mechanisms. At front of the recent identification of several Mg2+ entry mechanisms, the Mg2+ extrusion pathway(s) still remain(s) poorly characterized. Similarly, it remains not completely elucidated the physiological significance of these Mg2+ fluxes in the various tissues in which they occur. In the present review, we will attempt to provide a comprehensive framework of the modalities by which cellular Mg2+ homeostasis and transport are regulated, as well as examples of cellular functions regulated by changes in cellular Mg2+ level.

Introduction: Parathyroid carcinoma is a rare endocrine neoplasm, difficult to define clinically and histopathologically., Case Report: The case concerns of a 20 years old male with situs viscerum inversus (with dextrocardia), and symptoms: asthenia, oliguresis, nausea, emesis, myalgia, lower limb paresthesia and very high levels of calcium and PTH. Laboratory findings (PTH 580 pg/ml; Ca 12.40 mg/dl; P 1.9 mg/dl), echography, TC, and parathyroid scintigraphy, associated with clinical data, have suggested hypothesis of parathyroid carcinoma confirmed by histological examination and immunochemistry. Surgery was efficacious with normalization of Calcium and PTH levels, and disappearance of symptoms. After two years no signs of local recurrence were present, but imaging show pulmonary micronodulations of uncertain pathological meaning., Discussion and Conclusion: No clinical or bio-humoral data allows a preoperative diagnosis of parathyroid carcinoma. Only with definitive pathology and immunohistochemistry it is possible to differentiate an adenoma from a carcinoma. Surgery is the only effective therapy and therefore should be always performed. This neoplasm usually relapses, locally first and later with distant metastases. For this reason after surgery the patients should always undergo a strict follow-up programme including evaluation of PTH and calcemia.

Several lines of research suggest that mitochondria play a role in the etiopathogenesis of diabetic cardiomyopathy, although the mechanisms involved are still debated. In the present study, we report that State 3 oxygen consumption decreases by approximately 35% with glutamate and by approximately 30% with succinate in mitochondria from diabetic rat hearts compared to controls. In these mitochondria the enzymatic activities of complex I and complex II are also decreased to a comparable extent. Western blot analysis of mitochondrial protein pattern using antibodies recognizing proteins modified by the lipid peroxidation product 4-hydroxynonenal indicates the FAD-containing subunit of succinate dehydrogenase as one of the targets of this highly reactive aldehyde. In rats diabetic for 6 or 12 weeks, insulin supplementation for 2 weeks decreases the level of protein modified by 4-hydroxynonenal and restores mitochondrial respiration and enzyme activity to control level. Taken together, these results: (1) indicate that 4-hydroxynonenal is endogenously produced within diabetic mitochondria and forms an adduct with selective mitochondrial proteins, (2) identify one of these proteins as a subunit of succinate dehydrogenase, and (3) provide strong evidence that insulin treatment can reverse and ameliorate free radical damage and mitochondrial function under diabetic conditions.

Colovesical fistulas represent a possible less frequent complication of diverticular disease of colon. They represent a complex condition because of the possible and unexpected evolution into a septic shock with a high risk of death. The Authors report three cases of colovesical fistula as a complication of diverticular disease. They underline the importance of early diagnosis, specific antibiotic therapy and appropriate surgical therapy realized in one or two stages according to general and local conditions of each patient.

The abundance of magnesium (Mg2+) within mammalian cells is consistent with its relevant role in regulating tissue and cell functions. At the last count, more than three hundred and fifty enzymes, aside from metabolic cycles, appear to require and be regulated by concentrations of Mg2+ that are well within the physiological range observed in tissues and cells. The absence of detectable major changes in cellular free [Mg2+], and the extremely slow turn-over of the cation across the cell plasma membrane under quiescent condition has supported for more than three decades the assumption that cellular Mg2+ content is kept constant at the level necessary for enzyme and channel function, and that its concentration does not require drastic and rapid changes to form complex with ATP and other phosphonucleotides. In the last decade, a large body of new experimental observations has significantly reverted this way of thinking. Compelling evidence now suggests that large fluxes of Mg2+ can cross the cell plasma membrane in either direction following a variety of hormonal and non-hormonal stimuli, resulting in major changes in total and, to a lesser extent, free Mg2+ content within tissues, and in a marked variation in the opposite direction of circulating Mg2+ level. The present review will attempt to update our knowledge in this area and provide some insights on how changes in cellular Mg2+ content can result in a modification of the activity rate for several cellular enzymes.

The stimulation of beta-adrenoceptors in cardiac cells results in a rapid loss of cellular Mg(2+). Because insulin physiologically counteracts several of the cellular effects mediated by the activation of beta-adrenoceptors and the elevation of cytosolic cAMP levels, we investigated whether insulin administration could prevent Mg(2+) mobilization from rat hearts and ventricular myocytes. Rat hearts were perfused in a retrograde Langendorff system, and the changes in extracellular Mg(2+) were measured by atomic absorbance spectrophotometry. Pretreatment of the hearts with 6 nmol/L insulin completely prevented the Mg(2+) extrusion induced by the beta-adrenergic agonist isoproterenol. Furthermore, the administration of insulin per se induced an accumulation of Mg(2+) by the heart. This accumulation was small but detectable in the presence of 25 to 35 micromol/L [Mg(2+)](o) and increased in proportion to [Mg(2+)](o). Insulin-mediated Mg(2+) accumulation was not observed in hearts perfused with a medium devoid of glucose or with a medium containing the inhibitors of glucose transport, cytochalasin B and phloretin. Insulin-stimulated [(3)H]2-deoxyglucose accumulation was measured in collagenase-dispersed cardiac ventricular myocytes in the presence of varying levels of [Mg(2+)](o). Glucose transport was not observed below 25 micromol/L [Mg(2+)](o), and it also increased in proportion to [Mg(2+)](o). Taken together, these results indicate the presence of a major uptake of Mg(2+) into cardiac cells that is stimulated by insulin and may require the insulin-induced operation of a glucose transporter. Hence, extracellular and/or intracellular Mg(2+) may modulate glucose transport and/or utilization.

The authors describe the possible application of Tc-99m (V) DMSA scintigraphy in pancreatic neuroendocrine tumors. In consideration of the common embryonic origin of these tumors and other neoplastic diseases (medullary thyroid carcinoma, pheocromocytoma, neuroblastoma) that have been well studied with radionuclide imaging, five cases of pancreatic neuroendocrine tumors (two insulinomas, one vipoma, and two unclassified neuroendocrine tumors) were successfully visualized with Tc-99m (V) DMSA scintigraphy, thus giving an overall "imaging confirmation" of the histologic and/or cytologic results in terms of primary and metastatic localization. The authors point out the importance of their results, obtained in a simple and repeatable manner, and suggest a real comparison in this setting between this approach and octreotide scintigraphy.

The authors report a case of pancreatic malignant fibrous histiocytoma (approximately 22 cm). Clinical and instrumental approach for preoperative diagnosis is discussed and the anatomopathological features of the lesion, which is rarely localized in the pancreatic gland, are stressed. Surgical treatment is outlined as well.

The authors report a case of Kimura's disease recently observed. Diagnostic problems related to this rare pathologic condition as well as current and most reliable etiopathogenetic hypothesis are emphasized. Histopathological and clinical features are described in detail.