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The link between the business model (BM) and sustainability is recognized in tourism research and practice, especially as far as its socioeconomic consequences are concerned. Moreover, prior studies have highlighted some key factors influencing the sustainable business models (SBMs) of tourism firms but have mainly done so by adopting static perspectives. Thus, how these firms can contribute to sustainability through their BMs with positive effects, particularly on natural resources, remains overlooked. Thus, we adopt coevolutionary lenses to explore the main processes surrounding tourism firms' SBM. Coevolution conceives the firm-environment relationship as both circular, with mutual influence and reciprocal changes, and dialectical. Accordingly, we analyze 28 Italian agritourism firms during the COVID-19 pandemic emergency period focusing on the dynamics of their relationship with various multilevel actors (including institutions, local communities, tourists) by considering internal and external factors influencing their SBM. The dialectical nature of this relationship is stressed. We find three new factors: sustainable tourism culture, tourist loyalty, and local natural resource setting. Moreover, from the coevolutionary analysis of the findings, we derive a framework that conceptualizes agritourism SBMs as a virtuous coevolutionary process through effective coadaptations between multilevel actors influenced by 12 factors. Tourism entrepreneurs and policy-makers should carefully consider the factors influencing SBMs and try to act upon them to effectively organize and manage relationships of mutual functionality in light of current challenges, especially environmental concerns., (© 2023. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Background: Accurate estimation of the imminent fragility fracture risk currently represents a challenging task. The novel Fragility Score (FS) parameter, obtained during a Radiofrequency Echographic Multi Spectrometry (REMS) scan of lumbar or femoral regions, has been developed for the non-ionizing estimation of skeletal fragility., Aims: The aim of this study was to assess the performance of FS in the early identification of patients at risk for incident fragility fractures with respect to bone mineral density (BMD) measurements., Methods: Data from 1989 Caucasians of both genders were analysed and the incidence of fractures was assessed during a follow-up period up to 5 years. The diagnostic performance of FS to discriminate between patients with and without incident fragility fracture in comparison to that of the BMD T-scores measured by both Dual X-ray Absorptiometry (DXA) and REMS was assessed through ROC analysis., Results: Concerning the prediction of generic osteoporotic fractures, FS provided AUC = 0.811 for women and AUC = 0.780 for men, which resulted in AUC = 0.715 and AUC = 0.758, respectively, when adjusted for age and body mass index (BMI). For the prediction of hip fractures, the corresponding values were AUC = 0.780 for women and AUC = 0.809 for men, which became AUC = 0.735 and AUC = 0.758, respectively, after age- and BMI-adjustment. Overall, FS showed the highest prediction ability for any considered fracture type in both genders, resulting always being significantly higher than either T-scores, whose AUC values were in the range 0.472-0.709., Conclusion: FS displayed a superior performance in fracture prediction, representing a valuable diagnostic tool to accurately detect a short-term fracture risk., (© 2023. The Author(s).)

Microplastics (MPs) are critical emerging pollutants around the world. There is a growing interest in the effects of MP ingestion, non-digestion, and toxicity on aquatic organisms. Amphibian tadpoles are the vertebrate group that has received the least attention regarding this issue. The aim of the present study was to determine the ingestion of polyethylene MPs by Scinax squalirostris tadpoles by atomic force microscopy (AFM) and to evaluate the activities of carboxylesterase (CbE, using 4-naphthyl butyrate-NB-, and 1-naphthyl acetate -NA- as substrates) and alkaline phosphatase (ALP) under MP exposure. Enzyme activities were analyzed spectrophotometrically at 2 and 10 days of exposure. Tadpoles were exposed to two different treatments during 10 days: a negative control (CO, dechlorinated water) and MP (60 mg L -1 ). AFM images of the digestive contents of tadpoles revealed the presence of MPs. After 10 days of MP exposure, CbE (NB) activity was significantly higher and CbE (NA) activity was significantly lower in MP treatments than in controls. ALP activity decreased in MP treatments after 2 and 10 days of exposure. The detection of MP particles in the intestinal contents and the effects on metabolic enzymes in a common frog species evidenced the potential health risk of MP to aquatic vertebrates. Thus, the differential response in enzymes and substrates demonstrate the need for considering the complex effects of contaminants and nutrients on ecosystems for ecotoxicological risk characterization., (© 2022. The Author(s), under exclusive licence to Springer Nature Switzerland AG.)

Introduction: Posterior fossa syndrome (PFS) is a set of debilitating complications that can occur after surgery for posterior fossa tumors. This study aimed to assess the preoperative radiological and surgical risk factors for the onset of PFS in a histologically homogeneous population of children with medulloblastoma and compare it to a similar population of young adults., Methods: Included patients underwent posterior fossa surgery for medulloblastoma at 11 Italian neurosurgical wards (2003-2019) and were referred to Fondazione IRCCS Istituto Nazionale dei Tumori in Milan (INT) for postoperative treatments. We collected patients' pre- and post-operative clinical, surgical and radiological data from the INT charts. To compare the distribution of variables, we used the Mann-Whitney and Fisher tests for continuous and categorical variables, respectively., Results: 136 patients (109 children and 27 young adults) were included in the study. Among children, 29 (27%) developed PFS, and all of them had tumors at midline site with invasion of the fourth ventricle. Radiological evidence of involvement of the right superior (39% versus 12%; p = 0.011) or middle cerebellar peduncles (52% versus 18%; p = 0.002) seemed more common in children who developed PFS. Young adults showed an expected lower incidence of PFS (4 out of 27; 15%), that may be due to anatomical, physiological and oncological elements., Conclusions: This study confirmed some factors known to be associated with PFS onset and shed light on other debated issues. Our findings enhance an already hypothesized role of cerebellar language lateralization. The analysis of a population of young adults may shed more light on the often-neglected existence of PFS in non-pediatric patients., (© 2022. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Background: Decision-making in intraductal papillary mucinous neoplasms (IPMNs) of the pancreas depends on scaling the risk of malignancy with the surgical burden of a pancreatectomy. This study aimed to develop a preoperative, disease-specific tool to predict surgical morbidity for IPMNs., Methods: Based on preoperative variables of resected IPMNs at two high-volume institutions, classification tree analysis was applied to derive a predictive model identifying the risk factors for major morbidity (Clavien-Dindo ≥3) and postoperative pancreatic insufficiency., Results: Among 524 patients, 289 (55.2%) underwent pancreaticoduodenectomy (PD), 144 (27.5%) underwent distal pancreatectomy (DP), and 91 (17.4%) underwent total pancreatectomy (TP) for main-duct (18.7%), branch-duct (12.6%), or mixed-type (68.7%) IPMN. For 98 (18.7%) of the patients, major morbidity developed. The classification tree distinguished different probabilities of major complications based on the type of surgery (area under the surve [AUC] 0.70; 95% confidence interval [CI], 0.63-0.77). Among the DP patients, the presence of preoperative diabetes identified two risk classes with respective probabilities of 5% and 25% for the development of major morbidity, whereas among the PD/TP patients, three different classes with respective probabilities of 15%, 20%, and 36% were identified according to age and body mass index (BMI). Overall, history of diabetes, age, and cyst size segregated three different risk classes for new-onset/worsening diabetes., Conclusions: In presumed IPMNs, the disease-specific risk of major morbidity and pancreatic insufficiency can be determined in the preoperative setting and used to personalize the possible surgical indication. Age and overweight status in case of PD/TP and diabetes in case of DP tip the scale toward less aggressive clinical management in the absence of features suggestive for malignancy., (© 2022. The Author(s).)

Fipronil is a broad-use insecticide with severe toxicity to fish. Biomarkers responses and bioaccumulation were evaluated on Prochilodus lineatus after exposure to environmentally relevant concentrations of fipronil (0.5 μg L -1 , 9 μg L -1 , and 100 μg L -1 ) in a prolonged flow-through assay and ex vivo gills short-term exposition. Lipid peroxidation (LPO), oxidatively modified proteins (PO), the activity of superoxide dismutase (SOD), the content of reduced glutathione (GSH), antioxidant capacity against peroxyles (ACAP), and acetylcholinesterase (AChE) were evaluated. Besides, levels of fipronil and metabolites were analyzed by GC-ECD. At the end of the flow-through assay, fipronil, Fp. sulfone and Fp. desulfinyl were detected in fish, being liver the target organ. Fipronil prolonged exposition promoted oxidative damage in lipids and proteins, alterations in the defense system and low-antioxidant capacity in organs of P. lineatus. The brain AChE activity was affected after prolonged exposition. Ex vivo gills exposition to fipronil promoted changes in antioxidant capacity and damage to lipids, providing a fast and suitable test to assess the pesticide exposure in fish. The results revealed that fipronil at environmental concentrations would be an inducer of oxidative stress in this fish, becoming a vulnerable species to the effects of fipronil in aquatic environments., (© 2021. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

The Atlantic Rainforest is among the main biodiversity hotspots in the world, the Yabotí Biosphere Reserve (YBR) being one of the most important remaining areas. Agriculture practices could lead to intensive usage of pesticides resulting in a risk to the environment and human health. Water, suspended particulate matter (SPM), sediment, and fish (Andromakhe paris and Andromakhe saguazu) samples were collected from four streams with different degrees of protection of the YBR in two periods in order to assess the distribution of 18 organochlorine pesticides. Legacy and current-use pesticides were found in the different environmental matrices of the stream headwaters in non-anthropized areas within the buffer zone that drains the intangible area. A similar occurrence pattern of pesticides was found in all matrices. Levels of DDTs (<3.63 ng/L) and endosulfans (<21.8 ng/L) in surface water were above international guidelines for the protection of aquatic life in several streams for both sampling periods. HCHs, DDTs, endosulfans, and chlorpyrifos were detected in SPM and sediments from three streams, while γ-HCH (<60.3 ng/g lipid weight), chlorpyrifos (<698 ng/g lw), p,p´-DDD (<367 ng/g lw), and α-endosulfans (<209 ng/g lw) were detected in fish muscle in several streams. Chlorpyrifos and endosulfans were associated with current use, while DDx/DDT ratios suggested an old use. The concentration of pesticides found would not represent a risk to human health; however, it highlights the need to establish better regulation and action guidelines to reduce the anthropogenic effect on natural reserves., (© 2021. The Author(s), under exclusive licence to Springer-Verlag GmbH, DE part of Springer Nature.)

Nanostructured mesoporous materials of MCM-41 type were synthesized using a natural, non-toxic, and cheap source of silica from rice husk. Then, this pure silica was modified with several Fe loadings by a wet impregnation method. The chemical and physic properties of MCM-41 solids obtained were similar to those of MCM-41 synthesized from commercial silica by conventional method. Thus, all catalysts exhibited good structural regularity preserving the mesoporosity after the metal incorporation. The performance of the Fe/MCM-RHA composites as photo-Fenton heterogeneous catalysts was evaluated for photocatalytic degradation of different endocrine-disrupting chemicals (EDCs), such as herbicides (atrazine), and compounds derived from the plastic industry (bisphenol A) and the pharmaceutical industry (acetaminophen). The major photo-catalytic efficiency obtained (Fe/MCM-RHA(2.5)) is consistent with the highest presence of iron species, which are finely dispersed and stabilized on the silica structure, the isolated Fe 3+ ions being the accessible and active sites for the reaction. Finally, a cheaper solid arising from the valorization of residual biomass and with excellent photocatalytic performance for the degradation of EDCs (above 99%, 75%, and 60% for BPA, ATZ, and ACE respectively, in a reaction time of 240 min) was obtained.

BackgroundWe investigated the role of reactive oxygen species (ROS) in the anticancer mechanism of N-benzyl-2-nitro-1-imidazole-acetamide (BZN), a drug used in Chagas' disease treatment. MethodsBALB/c mice, inoculated with Ehrlich ascites carcinoma (EAC), were treated with BZN or BZN + Nacylcysteine (NAC) or NAC for 9 days. Subsequently, the inhibition of tumor growth and angiogenesis as well as animal survival were evaluated. Apoptosis and the cell cycle were evaluated using fluorescence microscopy and flow cytometry, while oxidative stress was evaluated by measuring TBARS content, DNA damage, calcium influx and ROS generation and antioxidant defenses (CAT, SOD, GPx, GST and GR). Immunoblotting was used to evaluate key death and cell cycle proteins. Results BZN treatment inhibited tumor progression (79%), angiogenesis (2.8-fold) and increased animal survival (29%). Moreover, BZN increased ROS levels (42%), calcium influx (55%), TBARS contents (1.9-fold), SOD (4.4-fold), GPx (17.5-fold) and GST (3-fold) activities and GSH depletion (2.5-fold) also caused DNA fragmentation (7.6-fold), increased cleaved PARP and promoted the trapping of cells in the G1 phase, as corroborated by the reduction in cyclin A and increased CDK2 protein levels. In silico DNA and molecular dynamic simulations showed H-bonds and hydrophobic interactions that were confirmed by circular dichroism. Increased apoptosis (232%), induced by treatment with BZN, was demonstrated by apoptotic cell staining and p53 level. Conclusion The current findings indicate that BZN acts as a tumor growth inhibitor and anti-angiogenic agent by ROS overgeneration, which interact with DNA causing damage and triggering apoptosis.

Little is known about the contribution of white matter integrity to inhibitory cognitive control, particularly in healthy aging. The present study examines the correspondence between white matter fiber bundle length and behavioral inhibition in 37 community-dwelling older adults (aged 51-78 years). Participants underwent neuroimaging with 3 Tesla MRI, and completed a behavioral test of inhibition (i.e., Go/NoGo task). Quantitative tractography derived from diffusion tensor imaging (qtDTI) was used to measure white matter fiber bundle lengths (FBLs) in tracts known to innervate frontal brain regions, including the anterior corpus callosum (AntCC), the cingulate gyrus segment of the cingulum bundle (CING), uncinate fasciculus (UNC), and the superior longitudinal fasciculus (SLF). Performance on the Go/NoGo task was measured by the number of commission errors standardized to reaction time. Hierarchical regression models revealed that shorter FBLs in the CING (p < 0.05) and the bilateral UNC (p < 0.01) were associated with lower inhibitory performance after adjusting for multiple comparisons, supporting a disconnection model of response inhibition in older adults. Prospective longitudinal studies are needed to examine the evolution of inhibitory errors in older adult populations and potential for therapeutic intervention.

This study deals with an experimental investigation into the trans-esterification behavior of two biocatalysts produced by different immobilization techniques of the same lipase from Pseudomonas cepacia . Biocatalysts catalyzed trans-esterification of commercial frying oil. It was verified that no enzyme leaching occurs and stepwise addition of ethanol is needed to improve the process performance. When stoichiometric ethanol has been added completely at the beginning of the reaction, percent mass fraction of esters reached 33% after 9 h and 52% after 30 h. Instead, when ethanol has been added in steps, ester production gradually increased at any time. Moreover, different amounts of biocatalyst were added to the reaction system and it was found that it is not necessary to add more than 3% of biocatalyst with respect to the oil mass to avoid inhibition. The immobilization method influences the reaction progress and the intermediate-glyceride profiles were analyzed. Results showed that the two biocatalysts have the same affinity towards triglycerides, but the covalently immobilized lipase ( epobond P. cepacia ) has a lower affinity towards diglycerides and monoglycerides and, in general, a lower activity than the absorbed lipase ( lipo P. cepacia )., Competing Interests: Conflict of interestOn behalf of all authors, the corresponding author states that there is no conflict of interest., (© King Abdulaziz City for Science and Technology 2019.)

SBA-15 and KIT-6 materials have been synthesized and modified with iron salts by the wet impregnation method with different metal loadings. The different mesostructures obtained were characterized by N 2 adsorption-desorption at 77 K, X-ray diffraction, temperature-programmed reduction, and ultraviolet-visible spectroscopy. These iron-containing mesostructured materials have been successfully tested for the heterogeneous photo-Fenton degradation of aqueous solutions of dangerous herbicides, such as atrazine, using UV-visible light irradiation, at room temperature and close to neutral pH. The results showed that the Fe/SBA-15 (10%) and Fe/KIT-6 (5%) catalysts exhibited the highest activities. However, the Fe/KIT-6 (5%) catalyst with minor Fe loading than Fe/SBA-15 (10%) presented a higher degradation of atrazine (above 98% in a reaction time of 240 min). Therefore, the interconnectivity of the cage-like mesopores had an important influence on the catalytic activity, favoring probably mass-transfer effects. Thus, the high performance of these materials indicates that the heterogeneous via of photo-Fenton process can also be efficiently employed to treat wastewaters containing pollutants such as herbicides, in order to reduce them to simplest and less toxic molecules.

Complications following lung transplantation may impede allograft function and threaten patient survival. The five main complications after lung transplantation are primary graft dysfunction, post-surgical complications, alloimmune responses, infections, and malignancy. Primary graft dysfunction, a transient ischemic/reperfusion injury, appears as a pulmonary edema in almost every patient during the first three days post-surgery. Post-surgical dysfunction could be depicted on computed tomography (CT), such as bronchial anastomosis dehiscence, bronchial stenosis and bronchomalacia, pulmonary artery stenosis, and size mismatch. Alloimmune responses represent acute rejection or chronic lung allograft dysfunction (CLAD). CLAD has three different forms (bronchiolitis obliterans syndrome, restrictive allograft syndrome, acute fibrinoid organizing pneumonia) that could be differentiated on CT. Infections are different depending on their time of occurrence. The first post-operative month is mostly associated with bacterial and fungal pathogens. From the second to sixth months, viral pneumonias and fungal and parasitic opportunistic infections are more frequent. Different patterns according to the type of infection exist on CT. Malignancy should be depicted and corresponded principally to post-transplantation lymphoproliferative disease (PTLD). In this review, we describe specific CT signs of these five main lung transplantation complications and their time of occurrence to improve diagnosis, follow-up, medical management, and to correlate these findings with pathology results. KEY POINTS: • The five main complications are primary graft dysfunction, surgical, alloimmune, infectious, and malignancy complications. • CT identifies anomalies in the setting of unspecific symptoms of lung transplantation complications. • Knowledge of the specific CT signs can allow a prompt diagnosis. • CT signs maximize the yield of bronchoscopy, transbronchial biopsy, and bronchoalveolar lavage. • Radiopathological correlation helps to understand CT signs after lung transplantation complications.

The contamination of drinking water resources by toxic metals is a major problem in many parts of the world, particularly in dense populated areas of developing countries that lack wastewater treatment facilities. The present study characterizes the recent evolution with time of some contaminants deposited in the Congo River and Lake Ma Vallée, both located in the vicinity of the large city of Kinshasa, capital of Democratic Republic of Congo (DRC). Physicochemical parameters including grain size distribution, organic matter and trace element concentrations were measured in sediment cores sampled from Congo River (n = 3) and Lake Ma Vallée (n = 2). The maximum concentration of trace elements in sediment profiles was found in the samples from the sites of Pool Malebo, with the values of 107.2, 111.7, 88.6, 39.3, 15.4, 6.1 and 4.7 mg kg(-1) for Cr, Ni, Zn, Cu, Pb, As and Hg, respectively. This site, which is characterized by intense human activities, is especially well known for the construction of numerous boats that are used for regular navigation on Congo River. Concerning Lake Ma Vallée, the concentration of all metals are generally low, with maximum values of 26.3, 53.6, 16.1, 15.3, 6.5 and 1.8 mg kg(-1) for Cr, Ni, Zn, Cu, Pb and As, respectively. However, the comparison of the metal profiles retrieved from the different sampled cores also reveals specific variations. The results of this study point out the sediment pollution by toxic metals in the Congo River Basin. This research presents useful tools for the evaluation of sediment contamination of river-reservoir systems.

This study was conducted to assess potential human health risks presented by pathogenic bacteria in a protected multi-use lake-reservoir (Lake Ma Vallée) located in west of Kinshasa, Democratic Republic of Congo (DRC). Water and surface sediments from several points of the Lake were collected during summer. Microbial analysis was performed for Escherichia coli, Enterococcus (ENT), Pseudomonas species and heterotrophic plate counts. PCR amplification was performed for the confirmation of E. coli, ENT, Pseudomonas spp. and Pseudomonas aeruginosa isolated from samples. The results reveal low concentration of bacteria in water column of the lake, the bacterial quantification results observed in this study for the water column were below the recommended limits, according to WHO and the European Directive 2006/7/CE, for bathing water. However, high concentration of bacteria was observed in the sediment samples; the values of 2.65 × 10(3), 6.35 × 10(3), 3.27 × 10(3) and 3.60 × 10(8) CFU g(-1) of dry sediment for E. coli, ENT, Pseudomonas spp. and heterotrophic plate counts, respectively. The results of this study indicate that sediments of the Lake Ma Vallée can constitute a reservoir of pathogenic microorganisms which can persist in the lake. Possible resuspension of faecal indicator bacteria and pathogens would affect water quality and may increase health risks to the population during recreational activities. Our results indicate that the microbial sediment analysis provides complementary and important information for assessing sanitary quality of surface water under tropical conditions.

Purpose: In this study, we determined normal serum butyrylcholinesterase (BChE) and carboxylesterase (CbE) activities in Tupinambis merianae in order to obtain reference values for organophosphorus pesticide monitoring., Methods: Forty-two T. merianae individuals were grouped by sex and size to identify potential differences in their enzyme levels to allow for proper representation of normal values for females, males, juveniles, and hatchlings. Mean CbE was determined using two model substrates: alpha-naphtylacetate (α-NA) and p-nitrophenyl valerate (4-NPV). BChE and CbE sensitivity to malaoxon (Mx) was also evaluated as well as the possibility of BChE reactivation with pyridine-2-aldoxime methochloride (2-PAM)., Results: Mean adult females' BChE was significantly higher than adult males, juveniles, and hatchlings. No significant differences were found between groups regarding CbE. CbE (4-NPV) activity showed slightly negative correlation with lizard snout-vent length, while BChE and CbE (α-NA) showed no correlation with body size. Apparent IC(50) values for BChE and CbE (α-NA) suggested different sensitivities among groups. CbE (4-NPV) could not be inhibited. All Mx-inhibited groups treated with 2-PAM in a final concentration of 2.8 mM showed clear signs of reactivation., Conclusions: In conclusion, the results demonstrate that (1) plasma esterase activity did not vary with age and sex, except for BChE activity, and (2) because biological and environmental variables could be confounding factors in the response of plasma cholinesterases, complementary biomarkers like CbE inhibition and oxime-induced reactivation of esterases are strongly recommended.

An increasing number of advanced therapy medicinal products (ATMPs) are under development and in clinical trials. Patients are central to this progress. In research, patients have funded, catalysed, coordinated and led projects. In regulation, patient groups have contributed to the creation of the political momentum for regulation of ATMPs, contributed to the debate and now participate in the regulatory process. Once licensed, patients will have a role in the pharmacovigilance, health technology assessment and reimbursement arrangements for these products. Patient groups contribute valuably as equal stakeholders at every step of the development of an ATMP.

Background: Nonoperative treatment of splenic injuries is the current standard of care for hemodynamically stable patients. However, uncertainty exists about its efficacy for patients with major polytrauma, a high Injury Severity Score (ISS), a high grade of splenic injury, a low Glasgow Coma Score (GCS), and important hemoperitoneum. In these cases, the videolaparoscopic approach could allow full abdominal cavity investigation, hemoperitoneum evacuation with autotransfusion, and spleen removal or repair., Methods: This study investigated 11 hemodynamically stable patients with severe polytrauma who underwent emergency laparoscopy. The mean ISS was 29.0 +/- 3.9, and the mean GCS was 12.1 +/- 1.6. A laparoscopic splenectomy was performed for six patients, whereas splenic hemostasis was achieved for five patients, involving one electrocoagulation, one polar resection, and three polyglycolic mesh wrappings., Results: The average length of the operation was 121.4 +/- 41.6 min. There were two complications (18.2%), with one conversion to open surgery (9.1%), and no mortality., Conclusions: Laparoscopy is a safe, feasible, and effective procedure for evaluation and treatment of hemodynamically stable patients with splenic injuries for whom nonoperative treatment is controversial.

Declines in fine motor skills and cognitive function are well known features of human aging. Yet, the relationship between age-related impairments in motor and cognitive function remains unclear. Rhesus monkeys, like humans, show marked decline in cognitive and fine motor function with age and are excellent models to investigate potential interactions between age-related declines in cognitive and motor functioning. We investigated the relationships among cognition, motor function and age in 30 male and female rhesus monkeys, 5-28 years of age, tested on a battery of cognitive tasks [acquisition of the delayed non-matching-to-sample (DNMS), DNMS-120s, DNMS-600s, acquisition of delayed recognition span test (DRST), spatial-DRST and object-DRST] and a fine motor task (Lifesaver test). Global cognitive ability, as assessed by the cognitive performance index (CPI), was impaired with age in both sexes, while age-related motor slowing was found only in males. After age was controlled for, half the variance in CPI was predicted by motor speed, with better cognitive ability associated with slower motor skills. Analyses at the level of each cognitive task revealed that motor speed and age predicted the rate of acquisition of the DNMS. This relationship was robust in males and absent in females. Motor speed was not a significant predictor of any other cognitive variable. We conclude that the relationship between cognition and motor function (1) may be limited to non-spatial tasks; (2) exists independently of age; (3) may reflect different contributions of the fronto-striatal system; (4) may be particularly evident in males.

Several observations have been reported in the last years indicating that ceramide may activate the mitochondrial route of apoptosis. We show here that on addition of either C2- or C16-ceramide to mitochondria isolated from rat heart and suspended in a saline medium, release of cytochrome c and apoptosis-inducing factor (AIF) from the intermembrane space takes place. The release process is Ca2+ -independent and is not inhibited by Cyclosporin A (CsA). For the protein release process to occur, the presence of an oxidizable substrate is required. When mitochondria are suspended in sucrose instead of potassium medium, only short chain C2-ceramide causes cytochrome c release through a Ca2+ -dependent and CsA sensitive mitochondrial permeability transition (MPT) mechanism. The latter effect appears to be related to the membrane potential dissipating ability exhibited by short chain C2-ceramide.

Background: Bile duct injuries (BDIs) during laparoscopic cholecystectomy (LC) still are reported with greater frequency than during open cholecystectomy (OC)., Methods: In 1999, a retrospective study evaluating the incidence of BDIs during LC in the area of Rome from 1994 to 1998 (group A) was performed. In addition, a prospective audit was started, ending in December 2001 (group B)., Results: In group A, 6,419 LCs were performed (222 were converted to OC; 3.4%). In group B, 7,299 LCs were performed (225 were converted to OC; 3.1%). Seventeen BDIs (0.26%) occurred in group A and 16 (0.22%) in group B. Overall, mortality and major morbidity rates were 12.1% and 30.3%, respectively, without significant differences between the two groups., Conclusions: The incidence and clinical relevance of BDIs during LC in the area of Rome appeared to be stable over the past 8 years and were not influenced by the use of a prospective audit, as compared with a retrospective survey.

Background: Transanal endoscopic microsurgery (TEM) allows a precise, full-thickness resection of rectal tumors anywhere within the rectum. Unfortunately, the standard TEM technique needs complex and rather expensive equipment, demands high skill, and is attended by bleeding and oozing that may be challenging. A modified TEM procedure combining the new Storz operation rectoscope and ultrasonic dissection has been developed to overcome the limitations of the original technique., Methods: The Storz operation rectoscope features a 5-mm telescope combined with a single-monitor display. Standard laparoscopic instruments and the LCSC5 Ultracision Maniple are used for dissection and coagulation. Full-thickness resection is performed most often. Closure of the defect is accomplished by interrupted 3-0 polydoxanone sutures secured by extracorporeal slipknots., Results: Altogether, 18 TEMs have been performed according to the modified technique: 9 for malignant and 9 for benign lesions. The median operating time was 92.5 min for resection of malignant lesions and 40 min for resection of benign lesions. Two postoperative complications occurred: a bleeding and a partial dehiscence. The median follow-up periods were 35 months for malignant disease and 19.5 months for benign disease. No recurrence was observed., Conclusion: For tumors located up to 15 cm from the anal verge, TEM with the Storz rectoscope and ultrasonic dissection is indicated. Despite the complication described, coagulation is optimal and ultrasonic scissors allow working in a fairly bloodless field. The overall costs of the equipment are significantly lower.

Background: Laparoscopic cholecystectomy (LC) is the gold standard treatment of gallstones. Nevertheless, there are some pitfalls due to the limits of current technology and the use of inappropriate ligature material, with a relevant risk of injuries and postoperative, mainly biliary, complications. Ultrasonically activated scissors may divide both vessels and cystic duct, with no need of further ligature, and possibly reduce the risk of thermal injuries., Methods: A prospective nonrandomized clinical trial was started in 1999 to test harmonic shears (Ultracision, Ethicon Endo-Surgery, Cincinnati, OH, USA) in 461 consecutive patients undergoing LC in order to evaluate the theoretical benefits of ultrasonic dissection and the possible reduction in intraoperative bile duct injuries (BDIs) and postoperative complications. Patients were divided in two groups: in group 1 (HS; 331 patients) the operation was performed by Ultracision (including coagulation-division of cystic duct and artery); in group 2 (LOOP; 130 patients) the cystic duct, after coagulation-division by harmonic scissors, was further secured with an endo-loop. Both groups were further divided into two subgroups: expert and surgeon-in-training. The following categories of data were collected and analyzed: individual patient data, indication for laparoscopic cholecystectomy, surgical procedure data (associated procedures, intraoperative cholangiography, intraoperative complications, length of surgery, and conversion to open), and postoperative course data (postoperative morbidity, postoperative mortality, reinterventions, and postoperative hospital stay). Furthermore, biliary complications were analyzed as a single parameter comparing the incidence within groups and subgroups. Cumulative complications (intraoperative and postoperative) were also analyzed as a single parameter comparing their incidence in the series of each surgeon within the surgeon-in-training subgroup to the average results of the expert subgroup. Finally, length of surgery, postoperative complication rate, and length of postoperative hospital stay within subgroups were analyzed to evaluate the learning curve., Results: Overall conversion rate was 0.87%. The mean operating time was 76.8 min (median, 70 min) in group 1 and 97.5 min (median 90 min) in group 2. BDI occurred in 1 case (0.32%) in the surgeon-in-training subgroup. Overall BDI rate was 0.22% (1/461). The overall incidence of postoperative bile leak was 2.7% (9 patients of subgroup 1 and 1 patient of subgroup 2). Clinical observation with spontaneous resolution occurred in 4 patients, and in 1 case the management consisted in an endoscopic biliary drainage; surgery was requested in the remaining cases. A laparoscopic approach was successfully attempted in all cases. Overall morbidity rate was 8.76% in group 1 and 13.84% in group 2. Rates of major complications, overall biliary complication, and postoperative bile leaks within the expert and surgeon-in-training subgroup differ significantly (p = 0.026, p = 0.03, and p = 0.049, respectively). There was 1 death (0.22%) due to sepsis that resulted from a small bowel injury by trocar insertion. Mean postoperative stay was 4.28 days for group 1 and 5.05 days for group 2., Conclusion: No significant difference was found in both patient groups regarding postoperative mortality and complications, biliary complications, and especially cystic duct leaks. A retrospective comparison of literature data showed that use of ultrasonic dissection during LC seems to reduce the risk of BDI. Nevertheless, a learning curve in the use of ultrasonic-activated devices is required: a significant differences in postoperative major complications and biliary complications between the expert and the surgeon-in-training subgroups was shown. Furthermore, ultrasonic scissors misuse may cause bowel injuries in patients with severe adhesions, and this could represent a possible limitation for surgical safety.

The effect of different anions on the steady-state proton translocation in bovine bc1 complex reconstituted in liposomes was studied. The H+/e- ratio for vectorial proton translocation is at the steady state definitely lower than that measured at level flow, (0.3 vs. 1.0). The presence of azide or arachidonate at micro- and submicromolar concentrations, respectively, gave a substantial reactivation of the proton pumping activity at the steady state, without any appreciable effect on respiration-dependent transmembrane pH difference. Addition of azide to turning-over bc1 vesicles also caused a transition of b cytochromes toward oxidation. The results are discussed in terms of possible involvement of an acidic residue in the protonation of the semiquinone/quinol couple at the N side of the membrane.