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Intersite communication in dimeric enzymes, triggered by ligand binding, represents both a challenge and an opportunity in enzyme inhibition strategy. Though often understestimated, it can impact on the in vivo biological mechansim of an inhibitor and on its pharmacokinetics. Thymidylate synthase (TS) is a homodimeric enzyme present in almost all living organisms that plays a crucial role in DNA synthesis and cell replication. While its inhibition is a valid strategy in the therapy of several human cancers, designing specific inhibitors of bacterial TSs poses a challenge to the development of new anti-infective agents. N,O-didansyl-l-tyrosine (DDT) inhibits both Escherichia coli TS (EcTS) and Lactobacillus casei TS (LcTS). The available X-ray structure of the DDT:dUMP:EcTS ternary complex indicated an unexpected binding mode for DDT to EcTS, involving a rearrangement of the protein and addressing the matter of communication between the two active sites of an enzyme dimer. Combining molecular-level information on DDT binding to EcTS and LcTS extracted from structural and FRET-based fluorometric evidence with a thermodynamic characterization of these events obtained by fluorometric and calorimetric titrations, this study unveiled a negative cooperativity between the DDT bindings to the two monomers of each enzyme dimer. This result, complemented by the species-specific thermodynamic signatures of the binding events, implied that communication across the protein dimer was triggered by the first DDT binding. These findings could challenge the conventional understanding of TS inhibition and open the way for the development of novel TS inhibitors with a different mechanism of action and enhanced efficacy and specificity., 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 © 2024 The Author(s). Published by Elsevier Inc. All rights reserved.)

Background: Pulsed field ablation (PFA) is increasingly used in clinical practice for the treatment of atrial fibrillation. While the susceptibility of erythrocytes to electroporation is well established, the effect of cardiac PFA technologies on hemolysis has remained underreported. The aim of this study was to investigate the incidence, severity, and clinical impact of PFA-induced hemolysis., Methods: We included n=145 patients undergoing atrial fibrillation catheter ablation with a pentaspline PFA catheter (biphasic, bipolar pulses of 2 kV) and n=70 patients receiving radiofrequency ablation (40-90 W) at 4 high-volume European centers. The lesion set comprised pulmonary vein isolation for paroxysmal atrial fibrillation and pulmonary vein isolation±additional lesions for persistent atrial fibrillation. Hemolysis and renal function biomarkers were analyzed in blood samples at baseline, at the end of ablation, and 24 hours after the procedure., Results: Baseline characteristics were well balanced between groups (overall mean, 65.7±9.4 years; 69.3% male). The ablation procedures comprised a mean of 61.6±27.4 PFA deliveries and 26.3±15.0 minute RF duration. Hemolysis was detected in 94.3% versus 6.8% of patients after PFA versus radiofrequency ablation ( P <0.001): PFA was associated with significantly lower haptoglobin levels (0.5±0.4 versus 1.0±0.4 g/L), while free plasma hemoglobin (592.8±330.6 versus 147.8±183.0 mg/L), bilirubin (21.3±11.3 versus 14.8±8.8 µmol/L), and LDH (lactate dehydrogenase, 352.7±115.7 versus 253.2±56.5 U/L) were significantly higher after PFA versus radiofrequency ablation (all P <0.001). Hemolysis correlated with the number of PFA deliveries (r=0.62 [95% CI, 0.33-0.80]; P <0.001), with the highest severity occurring ≥54 PFA deliveries. After PFA, hemoglobinuria occurred in 36.4%, while creatinine increase was higher in patients with baseline glomerular filtration rate <50 mL/min versus baseline glomerular filtration rate >50 mL/min (Δcrea, 27.0±103.1 versus -0.2±12.1 µmol/L; P =0.010)., Conclusions: Intravascular hemolysis is a frequent finding after PFA and increases with the number of PFA deliveries. Until the clinical impact of PFA-associated hemolysis is fully elucidated, a careful titration of PFA deliveries during the ablation procedure is warranted.

In this work we developed an eco-friendly valorisation of Citrus wastes (CWs), through a solvent-assisted ultrasonication extraction technique, thus having access to a wide range of bio-active compounds and polysaccharides, extremely useful in different industrial sectors (food, cosmetics, nutraceutical). Water-based low-amplitude ultrasonication was examined as a potential method for pectin extraction as well as polar and non-polar citrus extractives (CEs), among which hesperidin and triglycerides of 18 carbon fatty acids were found to be the most representative ones. In addition, citric acid:glycerol (1:4)-based deep eutectic solvent (DES) in combination with ultrasonic extraction was utilized to extract microcellulose (CMC), from which stable cellulose nanocrystals (CNCs) with glycerol-assisted high amplitude ultrasonication were obtained. The physical and chemical properties of the extracted polysaccharides (pectin, micro and nanocellulose) were analysed through DLS, ζ-potential, XRD, HP-SEC, SEM, AFM, TGA-DSC, FTIR, NMR, and PMP-HPLC analyses. The putative structure of the extracted citrus pectin (CP) was analysed and elucidated through enzyme-assisted hydrolysis in correlation with ESI-MS and monosaccharide composition. The developed extraction methods are expected to influence the industrial process for the valorisation of CWs and implement the circular bio-economy., 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 © 2024 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Insect Odorant Binding Proteins (OBPs) constitute important components of their olfactory apparatus, as they are essential for odor recognition. OBPs undergo conformational changes upon pH change, altering their interactions with odorants. Moreover, they can form heterodimers with novel binding characteristics. Anopheles gambiae OBP1 and OBP4 were found capable of forming heterodimers possibly involved in the specific perception of the attractant indole. In order to understand how these OBPs interact in the presence of indole and to investigate the likelihood of a pH-dependent heterodimerization mechanism, the crystal structures of OBP4 at pH 4.6 and 8.5 were determined. Structural comparison to each other and with the OBP4-indole complex (3Q8I, pH 6.85) revealed a flexible N-terminus and conformational changes in the α4-loop-α5 region at acidic pH. Fluorescence competition assays showed a weak binding of indole to OBP4 that becomes further impaired at acidic pH. Additional Molecular Dynamic and Differential Scanning Calorimetry studies displayed that the influence of pH on OBP4 stability is significant compared to the modest effect of indole. Furthermore, OBP1-OBP4 heterodimeric models were generated at pH 4.5, 6.5, and 8.5, and compared concerning their interface energy and cross-correlated motions in the absence and presence of indole. The results indicate that the increase in pH may induce the stabilization of OBP4 by increasing its helicity, thereby enabling indole binding at neutral pH that further stabilizes the protein and possibly promotes the creation of a binding site for OBP1. A decrease in interface stability and loss of correlated motions upon transition to acidic pH may provoke the heterodimeric dissociation allowing indole release. Finally, we propose a potential OBP1-OBP4 heterodimer formation/disruption mechanism induced by pH change and indole binding., 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 B.V. All rights reserved.)

This paper explores the potential of a low-cost, advanced video-based technique for the assessment of structural damage to buildings caused by seismic loading. A low-cost, high-speed video camera was utilized for the motion magnification processing of footage of a two-story reinforced-concrete frame building subjected to shaking table tests. The damage after seismic loading was estimated by analyzing the dynamic behavior (i.e., modal parameters) and the structural deformations of the building in magnified videos. The results using the motion magnification procedure were compared for validation of the method of the damage assessment obtained through analyses of conventional accelerometric sensors and high-precision optical markers tracked using a passive 3D motion capture system. In addition, 3D laser scanning to obtain an accurate survey of the building geometry before and after the seismic tests was carried out. In particular, accelerometric recordings were also processed and analyzed using several stationary and nonstationary signal processing techniques with the aim of analyzing the linear behavior of the undamaged structure and the nonlinear structural behavior during damaging shaking table tests. The proposed procedure based on the analysis of magnified videos provided an accurate estimate of the main modal frequency and the damage location through the analysis of the modal shapes, which were confirmed using advanced analyses of the accelerometric data. Consequently, the main novelty of the study was the highlighting of a simple procedure with high potential for the extraction and analysis of modal parameters, with a special focus on the analysis of the modal shape's curvature, which provides accurate information on the location of the damage in a structure, while using a noncontact and low-cost method.

Among several proteins participating in the olfactory perception process of insects, Odorant Binding Proteins (OBPs) are today considered valid targets for the discovery of compounds that interfere with their host-detection behavior. The 3D structures of Anopheles gambiae mosquito AgamOBP1 in complex with the known synthetic repellents DEET and Icaridin have provided valuable information on the structural characteristics that govern their selective binding. However, no structure of a plant-derived repellent bound to an OBP has been available until now. Herein, we present the novel three-dimensional crystal structures of AgamOBP5 in complex with two natural phenolic monoterpenoid repellents, Carvacrol and Thymol, and the MPD molecule. Structural analysis revealed that both monoterpenoids occupy a binding site (Site-1) by adopting two alternative conformations. An additional Carvacrol was also bound to a secondary site (Site-2) near the central cavity entrance. A protein-ligand hydrogen-bond network supplemented by van der Waals interactions spans the entire binding cavity, bridging α4, α6, and α3 helices and stabilizing the overall structure. Fluorescence competition and Differential Scanning Calorimetry experiments verified the presence of two binding sites and the stabilization effect on AgamOBP5. While Carvacrol and Thymol bind to Site-1 with equal affinity in the submicromolar range, they exhibit a significantly lower and distinct binding capacity for Site-2 with Kd's of ~7 μΜ and ~18 μΜ, respectively. Finally, a comparison of AgamOBP5 complexes with the AgamOBP4-Indole structure revealed that variations of ligand-interacting aminoacids such as A109T, I72M, A112L, and A105T cause two structurally similar and homologous proteins to display different binding specificities., 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 B.V. All rights reserved.)

Waxy (WX) and high-amylose (HA) wheat flours have interesting functional and/or nutritional characteristics, but low technological properties compared to regular wheat. Here a set of three wheat lines, having different amylose content but sharing the same varietal background, were compared to shed light on the role of the amylose/amylopectin ratio on the protein conformational changes that lead to gluten formation. Despite the absence of differences in their protein profile, as also confirmed by thiolomic approaches, both WX and HA lines developed a weaker gluten than the control sample. The altered amylose/amylopectin ratio exerts a matrix effect establishing a competition for water with proteins, leading to a different protein structure and three-dimensional organization of the gluten network. These results add a piece to the understanding of the molecular aspects that oversee matrix effects on gluten formation in wheat, which description can be helpful for a rational optimization of the transformation process., 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 © 2022 Elsevier Ltd. All rights reserved.)

In this paper the opto-electrical nature of hydrogenated group IV alloys with optical bandgap energies ranging from 1.0 eV up to 2.3 eV are studied. The fundamental physical principles that determine the relation between the bandgap and the structural characteristics such as material density, elemental composition, void fraction and crystalline phase fraction are revealed. Next, the fundamental physical principles that determine the relation between the bandgap and electrical properties such as the dark conductivity, activation energy, and photoresponse are discussed. The unique wide range of IV valence alloys helps to understand the nature of amorphous (a-) and nanocrystalline (nc-) hydrogenated (:H) germanium films with respect to the intrinsicity, chemical stability, and photoresponse. These insights resulted in the discovery of i) a processing window that results in chemically stable Ge:H films with the lowest reported dark conductivity values down to 4.6·10 -4 (Ω ·cm) -1 for chemical vapor deposited Ge:H films, and ii) O, C and Sn alloying approaches to improve the photoresponse and chemical stability of the a/nc-Ge:H alloys., (© 2022 The Authors. Advanced Science published by Wiley-VCH GmbH.)

The National Institute of Crop Science, Rural Development Administration (RDA) of Korea is presently developing new rice varieties suitable for producing Western rice-based foods, such as risotto , a well-known Italian-style product. The study considered different milled rice from five Tongil-type and six Japonica-type varieties. Besides the biometric properties, cooking behaviour, starch properties, and in vitro digestibility of Korean rice samples were compared with those of the 'Carnaroli' Italian variety. The physicochemical traits of the Korean varieties extended over a vast range; the amylose content stood out (from 13.0 to 41.7%), influencing the hardness and stickiness of cooked samples, and their starch digestibility. Although none of the Korean varieties seemed to guarantee cooking performances for risotto similar to the 'Carnaroli' one, 'Saemimyeon' and 'Shingil' cvs were judged the best for this purpose up-to-now., Competing Interests: Conflict of interestThe authors declare that they have no conflict of interests., (© The Korean Society of Food Science and Technology 2022.)

Thermal treatments are widely applied to gluten-free (GF) flours to change their functionality. Despite the interest in using pulses in GF formulations, the effects of thermal treatment at the molecular level and their relationship with dough rheology have not been fully addressed. Raw and heat-treated red lentils were tested for starch and protein features. Interactions with water were assessed by thermogravimetric analysis and water-holding capacity. Finally, mixing properties were investigated. The thermal treatment of red lentils induced a structural modification of both starch and proteins. In the case of starch, such changes consequently affected the kinetics of gelatinization. Flour treatment increased the temperature required for gelatinization, and led to an increased viscosity during both gelatinization and retrogradation. Regarding proteins, heat treatment promoted the formation of aggregates, mainly stabilized by hydrophobic interactions between (partially) unfolded proteins. Overall, the structural modifications of starch and proteins enhanced the hydration properties of the dough, resulting in increased consistency during mixing.

Food contamination with pathogenic microorganisms, such as Listeria monocytogenes , Salmonella enterica , Staphylococcus aureus and Bacillus cereus , is a common health concern. Natural products, which have been the main source of antimicrobials for centuries, may represent a turning point in alleviating the antibiotic crisis, and plant polyphenolic compounds are considered a promising source for new antibacterial agents. Resveratrol and resveratrol-derived monomers and oligomers (stilbenoids) have been shown to exert a variegated pattern of efficacy as antimicrobials depending on both the polyphenols' structure and the nature of the microorganisms, and the bacterial cell membrane seems to be one of their primary targets.In this scenario and based on the thermodynamic information reported in the literature about cell membranes, this study aimed at the investigation of the direct interaction of selected stilbenoids with a simple but informative model cell membrane. Three complete stilbenoid "monomer/dimer/dehydro-dimer" sets were chosen according to different geometries and substitution patterns. Micro-DSC was performed on 2 : 3 DPPC : DSPC small unilamellar vesicles with incorporated polyphenols at physiological pH and the results were integrated using complementary NMR data. The study highlighted the molecular determinants and mechanisms involved in the stilbenoid-membrane interaction, and the results were well correlated with the microbiological evidence previously assessed.

In this work, we have analysed the binding of the Pt(II) complexes ([PtCl(4'-phenyl-2,2':6',2″-terpyridine)](CF 3 SO 3 ) ( 1 ), [PtI(4'-phenyl-2,2':6',2″-terpyridine)](CF 3 SO 3 ) ( 2 ) and [PtCl(1,3-di(2-pyridyl)benzene) ( 3 )] with selected model proteins (hen egg-white lysozyme, HEWL, and ribonuclease A, RNase A). Platinum coordination compounds are intensively studied to develop improved anticancer agents. In this regard, a critical issue is the possible role of Pt-protein interactions in their mechanisms of action. Multiple techniques such as differential scanning calorimetry (DSC), electrospray ionization mass spectrometry (ESI-MS) and UV-Vis absorbance titrations were used to enlighten the details of the binding to the different biosubstrates. On the one hand, it may be concluded that the affinity of 3 for the proteins is low. On the other hand, 1 and 2 strongly bind them, but with major binding mode differences when switching from HEWL to RNase A. Both 1 and 2 bind to HEWL with a non-specific (DSC) and non-covalent (ESI-MS) binding mode, dominated by a 1:1 binding stoichiometry (UV-Vis). ESI-MS data indicate a protein-driven chloride loss that does not convert into a covalent bond, likely due to the unfavourable complexes' geometries and steric hindrance. This result, together with the significant changes of the absorbance profiles of the complex upon interaction, suggest an electrostatic binding mode supported by some stacking interaction of the aromatic ligand. Very differently, in the case of RNase A, slow formation of covalent adducts occurs (DSC, ESI-MS). The reactivity is higher for the iodo-compound 2 , in agreement with iodine lability higher than chlorine.

The influence of free fatty acids (FFAs) on the nisin-membrane interaction was investigated through micro-DSC and fluorescence spectroscopy. A simple but informative model membrane was prepared (5.7 DMPC:3.8 DPPS:0.5 DOPC molar ratio) by considering the presence of different phospholipid headgroups in charge and size and different phospholipid tails in length and unsaturation level, allowing the discrimination of the combined interaction of nisin and FFAs with the single phospholipid constituents. The effects of six FFAs on membrane stability were evaluated, namely two saturated FFAs (palmitic acid and stearic acid), two monounsaturated FFAs ( cis -unsaturated oleic acid and trans -unsaturated elaidic acid) and two cis -polyunsaturated FFAs (ω-6 linoleic acid and ω-3 docosahexaenoic acid). The results permitted assessment of a thermodynamic picture of such interactions which indicates that the peptide-membrane interaction does not overlook the presence of FFAs within the lipid bilayer since both FFAs and nisin are able to selectively promote thermodynamic phase separations as well as a general lipid reorganization within the host membrane. Furthermore, the magnitude of the effects may be different depending on the FFA chemical structure as well as the membrane lipid composition.

A fifteen-components model membrane that reflected the 80 % of phospholipids present in Insulin Secretory Granules was obtained and thermodynamic exploitation was performed, through micro-DSC, in order to assess the synergic contributions to the stability of a mixed complex system very close to real membranes. Simpler systems were also stepwise investigated, to complete a previous preliminary study and to highlight a hierarchy of interactions that can be now summarized as phospholipid tail unsaturation > phospholipid tail length > phospholipid headgroup > membrane curvature. In particular, Small Unilamellar Vesicles (SUVs) that consisted in phospholipids with different headgroups (choline, ethanolamine and serine), was step by step considered, following inclusion of sphingomyelins and lysophosphatidylcholines together with a more complete fatty acids distribution characterizing the phospholipid bilayer of the Insulin Secretory Granules. The inclusion of cholesterol was finally considered and the influence of three FFAs (stearic, oleic and elaidic acids) was investigated in comparison with simpler systems, highlighting the magnitude of the effects on such a detailed membrane in the frame of Type 2 Diabetes Mellitus alterations., 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 © 2019 Elsevier B.V. All rights reserved.)

The utilization of liposomes in biomedical applications has greatly benefited the diagnosis and treatment of various diseases. These biomimetic nano-entities have been very useful in the clinical practice as drug delivery systems in their conventional form, comprising lipids as structural components. However, the scientific efforts have recently shifted towards the development of more sophisticated nanotechnological platforms, which apply functional biomaterials, such as stimuli-responsive polymers, in order to aid the drug molecule targeting concept. These nanosystems are defined as chimeric/mixed, because they combine more than one different in nature biomaterials and their development requires intensive study through biophysical and thermodynamic approaches before they may reach in vivo application. Herein, we designed and developed chimeric liposomes, composed of a phospholipid and pH-responsive amphiphilic diblock copolymers and studied their morphology and behavior based on crucial formulation parameters, including biomaterial concentration, dispersion medium pH and polymer composition. Additionally, their interactions with biological components, pH-responsiveness and membrane thermodynamics were assessed. Finally, preliminary in vivo toxicity experiments of the developed nanosystems were carried out, in order to establish a future protocol for full in vivo evaluation. The results have been correlated with the properties of the chimeric nanosystems and highlight the importance of such approaches for designing and developing effective nanocarriers for biomedical applications., (Copyright © 2019 Elsevier B.V. All rights reserved.)

A stepwise micro-DSC study of Small, Large and Giant Unilamellar Vesicles prepared as pure and mixed systems of DMPC, DPPC, DSPC and DOPC was performed, achieving the preparation of final model membranes whose phospholipid compositions represent the 75% in terms of the phospholipids tails and the 50% headgroups of the Insulin Secretory Granules (vesicles located in the pancreatic Langerhans β-cells and which are responsible for insulin and amylin storage and secretion in response to nutrient intake). Moreover, the effect of Free Fatty Acids, whose levels are recurrently altered in diabetic and/or obese subjects, on the thermodynamic stability of the final membranes was eventually investigated. The results allowed to discriminate each single thermodynamic contribution among the main factors that dictate the overall thermodynamic stability of these complex unilamellar systems evidencing mainly entropic effects hierarchically summarized as phospholipid unsaturations > phospholipid tail length > membrane curvature. The effect of the Free Fatty Acids highlighted a strong stabilizing effect on the membranes as well as more pronounced phase segregations in the case of saturated acids (palmitic and stearic), whereas the opposite effect was observed in the case of an unsaturated one (oleic)., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Objective: To evaluate whether fasting plasma glucose (FPG) within a normoglycemic range is associated with cardiometabolic risk factors (CMRF) among children and adolescents in an outpatient setting., Research Design and Methods: Subjects (780; age 6-16 years) with FPG <100 mg/dL were divided into tertiles of FPG., Results: BMI, waist circumference, homeostasis model assessment-insulin resistance, systolic blood pressure, and white blood cell (WBC) count (P < 0.0001) increased across tertiles of FPG. Subjects with high-normal FPG (89-99 mg/dL) showed a higher risk of insulin resistance, hypertension, and high WBC count compared with subjects with low-normal FPG, independent of BMI z score., Conclusions: In outpatient children and adolescents, higher FPG within the normal range is associated with several CMRF, independent of obesity. Thus the simple measurement of FPG may help identify subjects who warrant some monitoring in relation to cardiovascular risk.

Alanine aminotransferase (ALT) elevations are considered a surrogate marker of nonalcoholic liver disease and predict later development of diabetes and metabolic syndrome in adults. The aim of the present study is to evaluate the prevalence of high ALT levels in obese children using updated and sex-related cutoff ALT value (ALT >30 IU/L for boys and >19 IU/L for girls). We also analyzed the association between ALT levels and metabolic factors in the 2 sexes. Three-hundred fifty-eight obese children (168 boys and 190 girls; age range, 6-16 years) were studied. Inclusion criteria were as follows: obesity, defined by an individual body mass index (BMI) greater than or equal to the 95th percentile for age and sex; negativity of markers for viral hepatitis; and no alcohol consumption. Two hundred six nonobese children (92 boys and 114 girls; age range, 6-16 years) served as a control group for ALT levels. The percentage of obese children with elevated ALT was 36% in boys and 55% in girls. Obese boys with ALT greater than 30 IU/L showed higher mother's BMI (P < .025), BMI, waist circumference, insulin resistance evaluated with homeostasis model assessment (HOMA-IR) index (P < .0001, for all), and systolic and diastolic blood pressure (P < .025, for both) compared with those with ALT not exceeding 30 IU/L. The ALT levels correlated positively with mother's BMI, BMI, waist circumference, HOMA-IR, triglycerides, and blood pressure. In linear regression analysis, waist circumference was the only independent factor associated with ALT level (beta = 0.370, t = 3,905, P < .0001). Obese girls with ALT greater than 19 IU/L exhibited lower age (P < .025) and higher triglycerides (P < .0001) than girls with ALT not exceeding 19 IU/L. The ALT levels correlated positively with triglycerides and HOMA-IR and negatively with age and Tanner stage. In linear regression analysis, ALT levels were independently associated only with triglycerides (beta = 0.330, t = 4.588, P < .0001). Our study shows that a high proportion of obese children present elevated ALT levels. This abnormality is associated in boys, more than in girls, with preclinical traits of the metabolic syndrome. The adoption of sex-related cutoff of ALT levels is desirable also for the pediatric population.

Laparoscopic cholecystectomy is the suitable treatment for symptomatic cholelithiasis, even if the incidence of biliary lesions following this procedure may be up to threefold higher than that of open cholecystectomy. We report our experience concerning the incidence, aetiopathogenesis, diagnosis and treatment of complications in a homogeneous group of laparoscopic cholecystectomies. In a total of 492 laparoscopic cholecystectomies only three bile duct lesions were observed (0.6%); they were classified according to Bismuth and re-assessed according to Strasberg. They consisted in two biliary leakages and one bile duct stricture. All patients were evaluated by full blood test, ultrasonography and endoscopic retrograde cholangiopancreatography. Endoscopic treatment was successful in the two patients with biliary leakage, while the patient with a stricture required surgical therapy. In conclusion, we suggest that a correct knowledge of the aetiopathogenesis together with a multidisciplinary approach to the diagnosis appear to be the best method for the detection, complete classification and most suitable treatment of symptomatic cholelithiasis.

Background: Even though many types of reconstruction after total gastrectomy have been proposed to reduce postgastrectomy syndromes, choosing a method that would further improve the quality of life and nutrition of the gastrectomized patient is controversial. Hunt-Lawrence single pouch reconstruction seems to obtain better results compared with the more common Roux-en-Y technique, but both of these reconstructive approaches are associated with some reduction in food intake and some problems in achievement of ideal body weight., Methods: In this prospective, randomized trial, after total gastrectomy 18 patients had reconstruction according to the Hunt-Lawrence or single pouch technique (SP group), whereas for 23 patients, the technique was modified with construction of a second pouch in the distal portion of the jejunal loop (DP group). Patients in the two groups were compared at 12 months after surgery for problems in gastrointestinal function, quality of life, improvement in body weight and nutritional parameters, serum albumin, hemoglobin level, and serum protein., Results: The DP group demonstrated fewer symptom problems, better weight maintenance, and better laboratory values when compared with patients undergoing standard single jejunal pouch reconstruction., Conclusions: Reconstruction with use of a double pouch as a gastric substitute leads to better outcome assessments than with a single pouch reconstruction. Our double pouch technique has demonstrated significant improvement in quality of life and nutritional recovery in terms of functional results as well as patient satisfaction.

Different vascular clamp methods in liver surgery have led to less complications. The aim of this study was to evaluate the results after hepatic resection involving different vascular clamping methods and liver function outcome. Our study examined 46 patients who underwent surgery for liver lesions, developed on cirrhotic and noncirrhotic livers, applying the technique of selective clamping and pedicular clamping. There was one death (1/17; 5.9%) due to postoperative liver failure which occurred in a cirrhotic liver patient who underwent left hepatectomy with pedicular clamping. Complication rate was higher, but not significant (4/7; 57.1%) in the group with selective clamping compared to those with pedicular clamping (3/10; 30%). Hemorrhagic complications were observed in a higher rate among patients with selective clamping (3/7; 42.9%) compared to those with pedicular clamping (1/10; 10%). Selective clamping seems to find major indications in patients with chronic liver disease undergoing minimal hepatic resections. Intermittent pedicular clamping seems to be more effective in regards to blood loss and postoperative hepatic function.

As part of our effort in searching for genetic factors contributing to the susceptibility to atopy and asthma, we have focused on a 'positional candidate' approach in identifying CC chemokine gene polymorphisms and their functional correlates. To date, a single-nucleotide polymorphism was found in the RANTES proximal promoter region, and a high degree of sequence variation was identified in the 3'-untranslated region -of the eotaxin gene. Also, we are pursuing a series of functional genomics' studies designed to identify differentially expressed genes in a panel of allergen-specific human Th2 cells and in antigen-induced hyperreactive murine airways. This is performed using a combination of protocols including suppression-subtractive hybridization and cDNA array hybridizations with 18,363 nonredundant sequences. A data base is being generated from a list of subtracted cDNA sequences and array-positive clones to categorize differentially expressed genes. Sequences are being placed in biologically relevant categories on the basis of function (i.e., receptor, signal transduction pathways, transcription, and translation). With the increasing amount of sequence information compiled by the Human Genome Project, it will be particularly challenging to integrate functional gene-mapping efforts to define and compare aberrant genotypes/phenotypes in atopic diseases.

The factors controlling the dynamics of HIV-1 transmission from mother to infant are not clearly known. Previous studies have suggested the existence of maternal and placental protective mechanisms that inhibit viral replication in utero. Preliminary studies from our laboratory revealed that supernatant from placental stromal cells protected HIV-1-infected PBMC from virus-induced apoptosis and suppressed virus production. We have attempted to characterize the antiviral activity of this placental factor (PF) and delineate the stages of HIV-1 replication affected. This activity was not due to the presence of any known cytokine reported to have anti-HIV effect. Direct exposure to PF had no suppressive effect on the infectivity of cell-free HIV-1, and envelope-mediated membrane fusion appeared to be unaffected. Western blot analysis of HIV-1 from infected PBMC treated with PF revealed that expression of all viral proteins was reduced proportionately, both intracellularly and in released virions. However, exposure of HIV-1-infected cells to PF resulted in production of virions with 10-100-fold-reduced infectivity. PF-treated virions contained two- to threefold reduced ratios of cyclophilin A:Gag protein as compared with untreated virus. Reduced cyclophilin A content resulting in decreased binding of cyclophilin A to Gag could account, in part, for the observed reduction in infectivity. Our results suggest that placental cells produce an antiviral factor that protects the fetus during gestation and may have therapeutic potential.

Intraabdominal structures may be damaged during blind introduction of the first trocar for laparoscopic operations. In this study, 150 patients with gallbladder lithiasis who underwent laparoscopy were randomly assigned to two groups, a blind (V group) or an open (H group), in order to compare the results and the rate of complications. No mortality was observed. Major complications occurred in 3/75 (4%) patients of the V group and in 1/75 (1.3%) patient of the H group (p < 0.05). Minor complications occurred in 5/75 (6.7%) patients of either group. The achievement of pneumoperitoneum required 4.5+/-0.4 min in the V group and 3.2+/-0.2 min in the H group (p < 0.05). The open laparoscopic technique is safer and faster than the blind approach; therefore, it is proposed that this approach be routinely used in all laparoscopic procedures.

Congenitally acquired HIV infection may be uniquely suited to treatment via genetic engineering of CD34+ hematopoietic stem/progenitor cells. However, current technologies yield only a small percentage of mature cells that carry the inserted genes, and expression is frequently suppressed. Since clinical trials employing these methodologies have been proposed for anti-HIV gene therapy of HIV-infected children, we wished to assess, by in vitro modeling, the expected limits of transduction efficiency, expression, and antiviral activity using currently available methods. We measured retrovirus-mediated transduction in cord blood progenitors and their in vitro-derived progeny macrophages by Mo-MuLV vectors expressing a transdominant negative Rev (RevTD). CFU-GM transduction efficiency ranged from 7 to 85%, with an average of 28%. Semiquantitative DNA PCR demonstrated < or =100 vector sequence copies per 1000 cells in monocyte/macrophage cultures, which were grown without selection to better model in vivo conditions. When challenged with the macrophagetropic HIV-1BaL isolate, cultured macrophages from mock-transduced CFU-GM colonies supported infection in eight of eight experimental cultures, control LXSN-transduced progenitors supported infection in six of eight cultures, while macrophages derived from RevTD-transduced CFU-GM colonies supported infection in four of eight cultures. Although these results support the ability of neo(r) retroviral vectors containing RevTD to inhibit HIV replication, they indicate that further optimization of transduction efficiency and sustained expression will be required for effective anti-HIV protection in vivo.

Acute necrotizing pancreatitis involves high mortality. When diagnosed, the disease implies a choice of suitable timing and proper technique of surgical approach. The experience on 16 patients with acute necrotizing pancreatitis, 9 males and 7 females, mean age of 54.7 +/- 3.3 years, is presented in this study. Necrosectomy and continuous local lavage of abdominal collections and pancreatic necrotic surfaces was the most appropriate surgical treatment. The method seems able to remove necrosis and active biological compounds and would appear to achieve a limited mortality and morbidity. Necrosectomy and postoperative local lavage represent a therapeutic effective procedure.

Thirty-two patients with symptomatic gastroesophageal reflux disease were investigated by esophagogastroduodenoscopy, 24 h pH monitoring, esophageal manometry and measurement of gastric emptying of solids, in order to elucidate the relative importance of lower esophageal sphincter tone, amount of acid reflux and gastric emptying on the degree of esophagitis. The mechanical competency of lower esophageal sphincter was significantly deranged in patients with moderate/severe esophagitis than in patients with mild esophagitis. The gastric emptying time was significantly delayed in patients with moderate/severe esophagitis than in patients with mild esophagitis. No relationship was observed between amount of acid reflux, lower esophageal sphincter function and gastric emptying time. Our results suggest that resting pressure of lower esophageal sphincter and the gastric motor function play a major role in severity of reflux esophagitis.

The authors refer the results obtained with ultrasonography (US), percutaneous transhepatic cholangiography (PTC) and endoscopic retrograde cholangiography (ERC) in the diagnosis of obstructive jaundice. One-hundred and forty-four patients have been investigated, on the basis of biological, clinical and ultrasonographic findings, by PTC or ERC. The high percentage rate observed in PTC-approached patients suggests that the combination of US-PTC would appear to provide an important role in diagnosing obstructive jaundice.

To evaluate the influence of both ultrasonography and cholescintiscan on the choice of the treatment and prognosis of acute cholecystitis, the authors reviewed their series of 187 patients observed between 1974 and 1985. On the basis of diagnostic investigations employed, two distinct periods are considered, 1974-79 and 1980-85. In the I period, the exact diagnosis of the disease was obtained in 31 patients (26.3 percent) and the treatment was conservative in 81.3 percent of cases and surgical in 18.7 percent. In the II period, the disease was exactly diagnosed in 95.6 percent and all patients underwent surgery. The overall mortality and complication rate was respectively 5.1 percent and 11.8 percent in the I period and 1.1 percent and 5.8 percent in the II period. Authors conclude that ultrasonography and cholescintiscan, arising rapidly to the exact diagnosis of disease, influenced markedly the choice of surgical treatment, improving the prognosis of these patients.

The therapeutic action of Triazolam has been assessed against a placebo by administering the two substances on a double blind basis the evening prior to surgery. The results show that Triazolam was significantly better than the placebo as regards induction time and the duration and quality of sleep. There were few unimportant side-effects.

The intrasplenic autotransplant of pancreatic fragments in dogs subjected to total pancreatectomy can prevent diabetes as it maintains normoglycaemic condition and a normal insulinaemic response to i.v. infusion of glucose. By adopting a pancreatic tissue preparation technique which provides for a very short collagenasis digestion time (4 minutes), B cells took and normal glucidic metabolism was maintained.

Superior mesenteric artery syndrome is an uncommon clinical condition. A case of duodenal vascular compression and a review of the literature are reported in order to clarify the pathophysiology of the disease. Diagnostic values of hypotonic duodenography and angiography are emphasized. Although, the significance of long-term pH monitoring and gastric emptying for preoperative study and its importance in follow-up after the surgical treatment are evaluated.

This study covers 14 patients subjected to truncal Vagotomy + Antrectomy acc. BI, in order to ascertain whether somatostatin is capable of inhibiting duodenal gastrin release. Somatostatin infusion significantly inhibits the gastrinic response to a protein meal, but does not affect basal levels of the hormone. This suggests that facilitation of duodenal gastrin release after vagal section may be mediated by the reduced somatostatin release.