Comparative Passivation of Si(100) by H2 and D2 Atmospheres under Simultaneous Xe+ Bombardment: An X-ray Photoelectron Spectroscopy Analysis

This study presents a comparison of H2 and D2 passivation on Si(100) under simultaneous Xe+ ion bombardment. The impact of Xe+ ions causes significant damage to the substrate surface, leading to an increase in H2 (D2) retention as Si-H (Si-D) bonds. The ion bombardment conditions are precisely controlled using a Kaufman ion gun. The atomic concentrations on the surface of the sample were investigated by quasi-in situ X-ray photoelectron spectroscopy. A simple methodology is employed to estimate the H (D) chemical concentration and the cover ratio of the sample, with regard to the oxygen concentration through residual water chemisorption present in the vacuum vessel. Differences in passivation are expected when using H2 or D2 atmospheres because their retained scission energies and physisorption properties differ. The results indicate an increase of the sticking coefficient for D2 and H2 under the ion bombardment. It is also found that the flux of H2 (D2) impinging on the surface contributes to play an important role in the whole process. Finally, a model is proposed to describe the phenomenon of the passivation of Si under Xe+ ion bombardment in the presence of H2 (D2).

The effects of gestational age on neonatal cholestasis: A retrospective cohort study

BACKGROUND

Reference guidelines for neonatal conjugated hyperbilirubinemia (cholestasis) management use a uniform approach regardless of gestational age (GA). We hypothesize that the clinical pattern of neonatal cholestasis is tightly related to GA. The aim of this study was to describe the effects of GA on neonatal cholestasis.

METHODS

A retrospective 4-year cohort study in a 70-bed neonatal care unit. Neonates with conjugated bilirubin≥34.2μmol/L (2 mg/dL) were identified. The incidence, clinical characteristics, etiology, treatment, and prognosis were compared between infants <32 and≥32 weeks GA.

RESULTS

Overall incidence of cholestasis was 4% (125/3402). It was >5 times higher and the mean duration was >1.5 times longer in neonates <32 weeks GA (10% versus 1.8%, p <0.01 and 49 versus 31 days, p <0.01, respectively). The onset of cholestasis was later in neonates <32 weeks (22 versus 10 days of life, p <0.001). This later onset of cholestasis was associated with parenteral nutrition, whereas the earlier onset was associated with other causes. Treatment using fish oil lipids was more frequently administrated to infants <32 weeks GA, whereas Ursodeoxycholic acid was administrated more frequently in≥32 weeks GA. Cholestasis resolved during hospitalization in 73% of <32 versus 38% in≥32 weeks GA infants (p <0.01).

CONCLUSIONS

The incidence, clinical presentation, etiology, treatment, and clinical evolution of neonatal cholestasis were all significantly affected by GA. Our results support the use of a GA-oriented approach for the management of neonatal cholestasis.

A short sequence in the tail of SARS-CoV-2 envelope protein controls accessibility of its PDZ-binding motif to the cytoplasm

The carboxy-terminal tail of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) envelope protein (E) contains a PDZ-binding motif (PBM) which is crucial for coronavirus pathogenicity. During SARS-CoV-2 infection, the viral E protein is expressed within the Golgi apparatus membrane of host cells with its PBM facing the cytoplasm. In this work, we study the molecular mechanisms controlling the presentation of the PBM to host PDZ (PSD-95/Dlg/ZO-1) domain-containing proteins. We show that at the level of the Golgi apparatus, the PDZ-binding motif of the E protein is not detected by E C-terminal specific antibodies nor by the PDZ domain-containing protein-binding partner. Four alanine substitutions upstream of the PBM in the central region of the E protein tail is sufficient to generate immunodetection by anti-E antibodies and trigger robust recruitment of the PDZ domain-containing protein into the Golgi organelle. Overall, this work suggests that the presentation of the PBM to the cytoplasm is under conformational regulation mediated by the central region of the E protein tail and that PBM presentation probably does not occur at the surface of Golgi cisternae but likely at post-Golgi stages of the viral cycle.

Neuroinvasion and anosmia are independent phenomena upon infection with SARS-CoV-2 and its variants

Anosmia was identified as a hallmark of COVID-19 early in the pandemic, however, with the emergence of variants of concern, the clinical profile induced by SARS-CoV-2 infection has changed, with anosmia being less frequent. Here, we assessed the clinical, olfactory and neuroinflammatory conditions of golden hamsters infected with the original Wuhan SARS-CoV-2 strain, its isogenic ORF7-deletion mutant and three variants: Gamma, Delta, and Omicron/BA.1. We show that infected animals develop a variant-dependent clinical disease including anosmia, and that the ORF7 of SARS-CoV-2 contributes to the induction of olfactory dysfunction. Conversely, all SARS-CoV-2 variants are neuroinvasive, regardless of the clinical presentation they induce. Taken together, this confirms that neuroinvasion and anosmia are independent phenomena upon SARS-CoV-2 infection. Using newly generated nanoluciferase-expressing SARS-CoV-2, we validate the olfactory pathway as a major entry point into the brain in vivo and demonstrate in vitro that SARS-CoV-2 travels retrogradely and anterogradely along axons in microfluidic neuron-epithelial networks.

A290 PHENOTYPE AND OUTCOME OF PATIENTS HOSPITALIZED FOR ACUTE PANCREATITIS IN A TERTIARY PEDIATRIC CENTER

Background

A recent meta-analysis of 48 studies, showed an equal prevalence of AP (16%) among the following etiologies; systemic disease, alcohol, medication, genetics, gallstones and infection in North American hospitalized and ambulatory pediatric patients. However, data on the epidemiology of severe pediatric acute pancreatitis (AP) in Canada are lacking.

Purpose

We aim to evaluate the clinical presentation, etiologies, comorbidities and outcome of pediatric patients with AP admitted to a tertiary hospital in Quebec, Canada.

Method

A retrospective observational cohort study (January 2014-December 2021) was performed at the CHU Sainte-Justine. Descriptive analyses were performed with SAS statistical softwar

Result(s)

Among the 214 patients included (110 (51%) males), 58 (27.1%) were already hospitalized at time of AP diagnosis (AP as secondary diagnosis) while 156 (72.9%) were admitted from the emergency room mainly with a presentation of abdominal pain (AP as primary diagnosis). Thirty-two patients (15.0%) were transferred to the ICU due to hemodynamic instability or respiratory failure. Comorbidities included cancer (38 patients (17.7%)), obesity (17 (7.9%)) and inflammatory bowel disease (15 (7.0%)). The three most commonly identified etiologies were medication (19.6%), biliary disease (16.3%) and infection (14,9%). Despite extensive investigations, 26.2% of cases were idiopathic. The main complications were, ascites (48 patients (22.4%)), necrotic pancreatitis (10 (4.6%)) and pancreatic pseudocyst (10 (4.6%)). The median duration of hospitalization for AP as a primary diagnosis was 4 days (interquartile range (IQR) 2-7) as compared to 22 (11-37) for AP as a secondary diagnosis.

Conclusion(s)

Approximately one third of hospitalized patients had an underlying condition requiring treatments that could cause AP, which explains the high prevalence of drug-induced AP in this report. The longest hospitalizations were associated with AP as secondary diagnosis. Ongoing work will identify factors associated with disease severity and outcome in particular in primary AP.

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Disclosure of Interest

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Systematic review of response criteria and endpoints in autoimmune hepatitis by the International Autoimmune Hepatitis Group

BACKGROUND & AIMS

Autoimmune hepatitis (AIH) has been well characterised and codified through the development of diagnostic criteria. These criteria have been adapted and simplified and are widely used in clinical practice. However, there is a need to update and precisely define the criteria for both treatment response and treatment.

METHODS

A systematic review was performed and a modified Delphi consensus process was used to identify and redefine the response criteria in autoimmune hepatitis.

RESULTS

The consensus process initiated by the International Autoimmune Hepatitis Group proposes that the term 'complete biochemical response' defined as 'normalization of serum transaminases and IgG below the upper limit of normal' be adopted to include a time point at 6 months after initiation of treatment. An insufficient response by 6 months was a failure to meet the above definition. Non-response was defined as '<50% decrease of serum transaminases within 4 weeks after initiation of treatment'. Remission is defined as liver histology with a Hepatitis Activity Index <4/18. Intolerance to treatment was agreed to stand for 'any adverse event possibly related to treatment leading to potential drug discontinuation'.

CONCLUSIONS

These definitions provide a simple and reproducible framework to define treatment response and non-response, irrespective of the therapeutic intervention. A consensus on endpoints is urgently required to set a global standard for the reporting of study results and to enable inter-study comparisons. Future prospective database studies are needed to validate these endpoints.

LAY SUMMARY

Consensus among international experts on response criteria and endpoints in autoimmune hepatitis is lacking. A consensus on endpoints is urgently required to set a global standard for the reporting of study results and to enable the comparison of results between clinical trials. Therefore, the International Autoimmune Hepatitis Group (IAIHG) herein presents a statement on 5 agreed response criteria and endpoints: complete biochemical response, insufficient response, non-response, remission, and intolerance to treatment, which can be used to guide future reporting.

Interactions of Severe Acute Respiratory Syndrome Coronavirus 2 Protein E With Cell Junctions and Polarity PSD-95/Dlg/ZO-1-Containing Proteins

The C-terminus of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) protein E contains a PBM (PDZ-binding motif) targeting PDZ (PSD-95/Dlg/ZO-1) domains, which is identical to the PBM of SARS-CoV. The latter is involved in the pathogenicity of the virus. Recently, we identified 10 human PDZ-containing proteins showing significant interactions with SARS-CoV-2 protein E PBM. We selected several of them involved in cellular junctions and cell polarity (TJP1, PARD3, MLLT4, and LNX2) and MPP5/PALS1 previously shown to interact with SARS-CoV E PBM. Targeting cellular junctions and polarity components is a common strategy by viruses to hijack cell machinery to their advantage. In this study, we showed that these host PDZ domains TJP1, PARD3, MLLT4, LNX2, and MPP5/PALS1 interact in a PBM-dependent manner in vitro and colocalize with the full-length E protein in cellulo, sequestrating the PDZ domains to the Golgi compartment. We solved three crystal structures of complexes between human LNX2, MLLT4, and MPP5 PDZs and SARS-CoV-2 E PBM highlighting its binding preferences for several cellular targets. Finally, we showed different affinities for the PDZ domains with the original SARS-CoV-2 C-terminal sequence containing the PBM and the one of the beta variant that contains a mutation close to the PBM. The acquired mutations in the E protein localized near the PBM might have important effects both on the structure and the ion-channel activity of the E protein and on the host machinery targeted by the variants during the infection.

A206 EVOLUTION OF PEDIATRIC AUTOIMMUNE CHOLANGITIS AND PRIMARY SCLEROSING CHOLANGITIS INTO ADULTHOOD

Background

The natural history of primary sclerosing cholangitis (PSC) in children seems to differ from PSC in adults. However, studies on this matter have been limited by short follow-up periods and inconsistent classification of patients with autoimmune cholangitis (AIC) (or overlap syndrome). Consequently, it remains unclear if long-term outcomes are affected by the clinical phenotype.

Aims

The aims of this is study are to describe the long-term evolution of PSC and AIC in a pediatric cohort with extension of follow-up into adulthood and to evaluate the influence of phenotype on clinical outcomes.

Methods

This is a retrospective study of patients with AIC or PSC followed at CHU-Sainte-Justine, a pediatric referral center in Montreal. All charts between January 1998 and December 2019 were reviewed. Patients were classified as either AIC (duct disease on cholangiography with histological features of autoimmune hepatitis) or PSC (large or small duct disease on cholangiography and/or histology). Extension of follow-up after the age of 18 was done for patients followed at the Centre hospitalier de l’Université de Montréal. Clinical features at diagnosis, response to treatment at one year and liver-related outcomes were compared.

Results

40 patients (27 PSC and 13 AIC) were followed for a median time of 71 months (range 2 to 347), with 52.5% followed into adulthood. 70% (28/40) had associated inflammatory bowel disease (IBD) (78% PSC vs 54% AIC; p=0.15). A similar proportion of patients had biopsy-proven significant fibrosis at diagnosis (45% PSC vs 67% AIC; p=0.23). Baseline liver tests were similar in both groups.

At diagnosis, all patients were treated with ursodeoxycholic acid. Significantly more patients with AIC (77% AIC vs 30 % PSC; p=0.005) were initially treated with immunosuppressive drugs, without a significant difference in the use of Anti-TNF agents (0% AIC vs 15% PSC; p= 0.12). At one year, 55% (15/27) of patients in the PSC group had normal liver tests versus only 15% (2/13) in the AIC group (p=0.02).

During follow-up, more liver-related events (cholangitis, liver transplant and cirrhosis) were reported in the AIC group (HR=3.7 (95% CI: 1.4–10), p=0.01). Abnormal liver tests at one year were a strong predictor of liver-related events during follow-up (HR=8.9(95% CI: 1.2–67.4), p=0.03), while having IBD was not (HR=0.48 (95% CI: 0.15–1.5), p=0.22). 5 patients required liver transplantation with no difference between both groups (8% CAI vs 15% CSP; p=0.53).

Conclusions

Pediatric patients with AIC and PSC show, at onset, similar stage of liver disease with comparable clinical and biochemical characteristics. However, patients with AIC receive more often immunosuppressive therapy and treatment response is less frequent. AIC is associated with more liver-related events and abnormal liver tests at one year are predictor of bad outcomes.

Funding Agencies

None

A219 EARLY PREDICTORS OF UNFAVORABLE OUTCOME IN NORTH AMERICAN INDIAN CHILDHOOD CIRRHOSIS

Background

North American Indian Childhood Cirrhosis (NAIC) has only been described in the Cree-Ojibway First Nations of Northern Quebec. NAIC presents with transient neonatal jaundice and progresses to biliary cirrhosis often requiring liver transplantation (LT) in childhood. Only 30 patients have been described to date and risk factors associated with an earlier progression to LT have not yet been identified. Moreover, NAIC patients seem to experience more fractures than other cholestatic patients, but this has not been confirmed.

Aims

With this study, we aimed to identify predictors at 6 months from presentation that might suggest progression to end-stage liver disease as well as evaluate bone health in affected patients.

Methods

The records of all NAIC patients diagnosed between 2000–2020 were reviewed. Subjects were split into 2 groups based on whether they had undergone LT or not (No_LT) before age 18. Recorded complications included: hepatic encephalopathy (HE), variceal bleeding (VB), ascites, spontaneous bacterial peritonitis (SBP), bacteremia, and pulmonary shunts. Laboratory data (alanine aminotransferase, ALT; total bilirubin, TB) were collected at presentation and follow-up. Bone mineral density (BMD) of the lumbar spine (Z-scores) and number of fractures were compared between groups. NAIC patients were then compared to cohorts with other chronic cholestatic diseases such as biliary atresia (BA, n=24) and Alagille syndrome (AS, n=11).

Results

A total of 14 patients (M=9, F=5) were diagnosed with NAIC. Average age at presentation was 2.1 months (IQR 1–16.9 months), with 3 patients older than 18 months. Overall, 6 patients were transplanted (avg 8.6±1.7 years), one was listed for LT but died waiting, and 7 remained in a state of compensated cirrhosis. All complications were only observed in the LT group except for VB which also occurred in 2 patients of the No_LT group. Between presentation and 6 months, ALT and TB levels increased more in the LT vs No_LT group (p=ns). There was a greater variation of ALT/TB levels in the LT group (p=0.0047) even once the 3 patients with late referral were excluded (p=0.0381). No patient in the No_LT group had fractures, while 3 did in the LT group. BMD was lower in the LT group vs No_LT group (-2.2±1.2 vs. -1.1±1.3, p=ns). NAIC patients had lower BMD (-1.7±1.3) than those with AS (0.7±0.9, p=0.003) or BA (-0.9±1.4, p=ns) and had a higher prevalence of fractures (21.4% vs. 12.5% for BA and 18.2% for AS patients).

Conclusions

In patients with NAIC, variation of ALT/TB levels at 6 months from presentation may be used as an early predictor of unfavorable outcome and progression towards end-stage liver disease. Patients who evolved to LT had more complications, higher prevalence of fractures and lower BMD values. Compared to children with BA or AS, NAIC patients had poorer bone health.

Funding Agencies

None

Laparoscopic Liver Resection: A South American Experience with 2887 Cases

BACKGROUND

Laparoscopic liver resections (LLR) have been increasingly performed in recent years. Most of the available evidence, however, comes from specialized centers in Asia, Europe and USA. Data from South America are limited and based on single-center experiences. To date, no multicenter studies evaluated the results of LLR in South America. The aim of this study was to evaluate the experience and results with LLR in South American centers.

METHODS

From February to November 2019, a survey about LLR was conducted in 61 hepatobiliary centers in South America, composed by 20 questions concerning demographic characteristics, surgical data, and perioperative results.

RESULTS

Fifty-one (83.6%) centers from seven different countries answered the survey. A total of 2887 LLR were performed, as follows: Argentina (928), Brazil (1326), Chile (322), Colombia (210), Paraguay (9), Peru (75), and Uruguay (8). The first program began in 1997; however, the majority (60.7%) started after 2010. The percentage of LLR over open resections was 28.4% (4.4-84%). Of the total, 76.5% were minor hepatectomies and 23.5% major, including 266 right hepatectomies and 343 left hepatectomies. The conversion rate was 9.7%, overall morbidity 13%, and mortality 0.7%.

CONCLUSIONS

This is the largest study assessing the dissemination and results of LLR in South America. It showed an increasing number of centers performing LLR with the promising perioperative results, aligned with other worldwide excellence centers.

Behaviour of the Contact Phase of Blood Coagulation in the Adult Respiratory Distress Syndrome (ARDS)

In order to assess the role of the kallikrein-kinin (K-K) system in the pathogenesis of the adult respiratory distress syndrome (ARDS) we have prospectively determined coagulation contact phase, blood gas and hemodynamic parameters in patients with ARDS at 0, 36 and 72 h from diagnosis.

Compared to normal values, significantly lower mean levels of factor XII (71.4 ± 9.8%, p <0.0005), prekallikrein (PPK) (52 ± 5.7%, p <0.0005), high molecular weight kininogen (HMWK) (73 ± 2%, p <0.0005) and α2-macroglobulin (α2-M) (51 ± 7.1%, p <0.0005) were found in ARDS patients.

The functional kallikrein inhibitory activity (KKI) and Cr esterase inhibitor antigenic (CIINH) were significantly higher in these patients (113.2 ± 5, p <0.005 and 124.7 ± 7.6, p <0.0005 respectively) compared with normal values during the entire study period.

The KKI/CIINH ratio decreased significantly in our ARDS patients at 0, 36 and 72 h (p <0.025; p <0.05 and p <0.005 respectively).

We found a significant correlation between PPK levels and oxigenation index (r = 0.69, p <0.001), PPK and the static thoracic compliance values (r = 0.64, p <0.001). There was also a significant correlation between PPK levels and Qs/Qt (r = -0.89, p <0.001). ARDS patients that survived presented a stability in the PPK values in successive tests. Nevertheless non-survivors showed a progressive decrease in PPK levels during the follow-up period.

Our results suggest that the plasma kallikrein system becomes activated during ARDS and that this activation might increase the lung vessels’ permeability. In addition, PPK levels are in our opinion a useful prognostic parameter in predicting the outcome of ARDS patients.

On the phonon dissipation contribution to nanoscale friction by direct contact

The friction phenomenon is a ubiquitous manifestation of nature. Models considering phononic, electronic, magnetic, and electrostatic interactions are invoked to explain the fundamental forces involved in the friction phenomenon. In order to establish the incidence of the phonon prompting at the nanoscale friction by direct contact, we study a diamond spherical dome sliding on carbon thin films containing different amount of deuterium and hydrogen. The friction coefficient decreases by substituting hydrogen by deuterium atoms. This result is consistent with an energy dissipation vibration local mechanism from a disordered distribution of bond terminators.

Monitoring the efficacy of omega-3 supplementation on liver steatosis and carotid intima-media thickness: a pilot study

Purpose

To determine the effects of omega‐3 supplementation on liver fat and carotid intima–media thickness (IMT) and to assess accuracy of ultrasound (US) for grading liver steatosis.

Materials and Methods

In this one‐way crossover pilot study, we assigned children with obesity and liver steatosis to receive 1.2 g daily of omega‐3 supplementation vs. inactive sunflower oil for 24 or 12 weeks. Liver fat content was assessed by magnetic resonance spectroscopy (MRS), magnetic resonance imaging (MRI) and US, and common carotid IMT by US. Statistical analysis included Chi‐square, Student's t‐tests, ANOVA tests and receiver operating characteristic (ROC) curves.

Results

Omega‐3 supplementation was associated with a trend towards decrease in MRS‐determined liver fat fraction (0.7% and 2.1% decrease in the 24‐week and 12‐week omega‐3 group, respectively) compared with the sunflower oil group (1.0% increase). These changes were not significant, whether assessed by MRS (P = 0.508), MRI (P = 0.508) or US (P = 0.678). Using US, the area under the ROC curves were 0.964, 0.817 and 0.783 for distinguishing inferred steatosis grades 0 vs. 1–2–3, 0–1 vs. 2–3 and 0–1–2 vs. 3, respectively, indicating good accuracy of US‐based fat grading. Omega‐3 supplementation was associated with a decrease in US‐determined IMT (0.05‐mm decrease in the 24‐week omega‐3 group. A 0.015‐mm increase was found in the 12‐week omega‐3 group, and a 0.007‐mm decrease in the sunflower oil group (P = 0.003).

Conclusion

Omega‐3 supplementation had no significant effect on liver fat fraction, but led to carotid IMT decrease in children with obesity and liver steatosis.

Dielectric Susceptibility of Liquid Water: Microscopic Insights from Coherent and Incoherent Neutron Scattering

The analysis of neutron scattering results on H dynamics (H_{2}O) and the dynamic structure factor (D_{2}O) around the intermolecular peak and at intermediate length scales in terms of the susceptibilities reveals three processes (diffusive, local relaxational and vibrational) at frequencies below 3 THz, to which the contributions commonly invoked in dielectric studies can be directly mapped. We achieve a unified description of the results from both techniques, clarifying the nature of the molecular motions involved in the dielectric spectra and their impact on the structural relaxation.

The induction of autoimmune hepatitis in the human leucocyte antigen-DR4 non-obese diabetic mice autoimmune hepatitis mouse model

Autoimmune hepatitis (AIH) is a chronic liver disease characterized by progressive inflammation, female preponderance and seropositivity for autoantibodies such as anti-smooth muscle actin and/or anti-nuclear, anti-liver kidney microsomal type 1 (anti-LKM1) and anti-liver cytosol type 1 (anti-LC1) in more than 80% of cases. AIH is linked strongly to several major histocompatibility complex (MHC) alleles, including human leucocyte antigen (HLA)-DR3, -DR7 and -DR13. HLA-DR4 has the second strongest association with adult AIH, after HLA-DR3. We investigated the role of HLA-DR4 in the development of AIH by immunization of HLA-DR4 (DR4) transgenic non-obese diabetic (NOD) mice with DNA coding for human CYP2D6/FTCD fusion autoantigen. Immunization of DR4 mice leads to sustained mild liver injury, as assessed biochemically by elevated alanine aminotransferase, histologically by interface hepatitis, plasma cell infiltration and mild fibrosis and immunologically by the development of anti-LKM1/anti-LC1 antibodies. In addition, livers from DR4 mice had fewer regulatory T cells (T_regs ), which had decreased programmed death (PD)-1 expression. Splenic T_regs from these mice also showed impaired inhibitory capacity. Furthermore, DR4 expression enhanced the activation status of CD8⁺ T cells, macrophages and dendritic cells in naive DR4 mice compared to naive wild-type (WT) NOD mice. Our results demonstrate that HLA-DR4 is a susceptibility factor for the development of AIH. Impaired suppressive function of T_regs and reduced PD-1 expression may result in spontaneous activation of key immune cell subsets, such as antigen-presenting cells and CD8⁺ T effectors, facilitating the induction of AIH and persistent liver damage.

Quality improvement and geographical indication of cachaça (Brazilian spirit) by using locally selected yeast strains

AIMS

In order to improve the quality and to create a biological basis for obtainment of the protected denomination of origin (PDO), indigenous yeast were isolated and characterized for use in Salinas city (the Brazilian region of quality cachaça production).

MATERIAL AND METHODS

Seven thousand and two hundred yeast colonies from 15 Salinas city distilleries were screened based on their fermentative behaviour and the physicochemical composition of cachaça. Molecular polymorphic analyses were performed to characterize these isolates.

RESULTS

Two Saccharomyces cerevisiae strains (nos. 678 and 680) showed appropriate characteristics to use in the cachaça production: low levels of acetaldehyde and methanol, and high ethyl lactate/ethyl acetate ratio respectively. They also presented polymorphic characteristics more closely related between themselves even when compared to other strains from Salinas.

CONCLUSIONS

The application of selected yeast to cachaça production can contribute for the improvement of the quality product as well as be used as a natural marker for PDO.

SIGNIFICANCE AND IMPACT OF THE STUDY

This study suggests that the use of selected yeast strains could contribute to obtain a cachaça similar to those produced traditionally, while getting wide acceptation in the market, yet presenting more homogeneous organoleptic characteristics, and thus contributing to the PDO implementation.

Plasma fatty acid composition in French-Canadian children with non-alcoholic fatty liver disease: Effect of n-3 PUFA supplementation

Non-alcoholic fatty liver disease (NAFLD) represents one of the most common causes of liver disease worldwide. As the NAFLD pathogenesis is associated with diet and lifestyle, the aims of the present work are to assess fatty acid (FA) composition in NAFLD young French-Canadian, to determine whether treatment with n-3 FA improves the plasma FA profile, and to define the time on the effectiveness of n-3 FA supplementation. Baseline characteristics of the NAFLD subjects show increased, anthropometric and biochemical parameters. Their plasma FA composition is characterized by a percent increase in total n-6 FA and a high proportion of saturated and total monounsaturated FA, as well as a decrease in Δ5 and increase in Δ6 desaturases. In conclusion, our results document for the first time the composition of plasma FAs in NAFLD young French Canadian and the efficacy of 3-month supplementation to improve the proportion of n-3 FA in their plasma.

Identification of the Chemical Bonding Prompting Adhesion of a-C:H Thin Films on Ferrous Alloy Intermediated by a SiCx:H Buffer Layer

Amorphous carbon (a-C) and several related materials (DLCs) may have ultralow friction coefficients that can be used for saving-energy applications. However, poor chemical bonding of a-C/DLC films on metallic alloys is expected, due to the stability of carbon-carbon bonds. Silicon-based intermediate layers are employed to enhance the adherence of a-C:H films on ferrous alloys, although the role of such buffer layers is not yet fully understood in chemical terms. The chemical bonding of a-C:H thin films on ferrous alloy intermediated by a nanometric SiCx:H buffer layer was analyzed by X-ray photoelectron spectroscopy (XPS). The chemical profile was inspected by glow discharge optical emission spectroscopy (GDOES), and the chemical structure was evaluated by Raman and Fourier transform infrared spectroscopy techniques. The nature of adhesion is discussed by analyzing the chemical bonding at the interfaces of the a-C:H/SiCx:H/ferrous alloy sandwich structure. The adhesion phenomenon is ascribed to specifically chemical bonding character at the buffer layer. Whereas carbon-carbon (C-C) and carbon-silicon (C-Si) bonds are formed at the outermost interface, the innermost interface is constituted mainly by silicon-iron (Si-Fe) bonds. The oxygen presence degrades the adhesion up to totally delaminate the a-C:H thin films. The SiCx:H deposition temperature determines the type of chemical bonding and the amount of oxygen contained in the buffer layer.

Design and verification of the shielding around the new Neutron Standards Laboratory (LPN) at CIEMAT

The construction of the new Neutron Standards Laboratory at CIEMAT (Laboratorio de Patrones Neutrónicos) has been finalised and is ready to provide service. The facility is an ∼8 m×8 m×8 m irradiation vault, following the International Organization for Standardization 8529 recommendations. It relies on several neutron sources: a 5-GBq (5.8× 10(8) s(-1)) (252)Cf source and two (241)Am-Be neutron sources (185 and 11.1 GBq). The irradiation point is located 4 m over the ground level and in the geometrical centre of the room. Each neutron source can be moved remotely from its storage position inside a water pool to the irradiation point. Prior to this, an important task to design the neutron shielding and to choose the most appropriate materials has been developed by the Radiological Security Unit and the Ionizing Radiations Metrology Laboratory. MCNPX was chosen to simulate the irradiation facility. With this information the walls were built with a thickness of 125 cm. Special attention was put on the weak points (main door, air conditioning system, etc.) so that the ambient dose outside the facility was below the regulatory limits. Finally, the Radiation Protection Unit carried out a set of measurements in specific points around the installation with an LB6411 neutron monitor and a Reuter-Stokes high-pressure ion chamber to verify experimentally the results of the simulation.

A child with unresectable biliary rhabdomyosarcoma: 48-month disease-free survival after liver transplantation

We describe here a two-yr-old boy with biliary RMS successfully treated by chemotherapy and LT. The child presented with obstructive jaundice at 20 months of age. A mildly vascularized, non-calcified, partially cystic lesion was visualized in the left hepatic lobe. Solid infiltration of the common bile duct and of both left and right hepatic ducts was suspected. Liver biopsy suggested a botryoid-type embryonal RMS originating from the biliary tract. After extrahepatic spread of the tumor was excluded, a biliary drain was applied and neoadjuvant chemotherapy was started. After the treatment, although reduced in volume, the mass was still unresectable without aggressive surgery and gross residual disease. LT with a reduced segment II/III graft was performed four months after diagnosis. The patient received six cycles of adjuvant chemotherapy, and he is alive and recurrence-free 48 months post-transplantation. A posteriori, the transplant might have possibly been avoided with an aggressive resection with biliary reconstruction. Nevertheless, although the risk of the transplant has to be balanced against the chemoresponsiveness of the tumor, the four-yr disease-free survival of this patient suggests that, when coupled with effective chemotherapy, transplantation might be considered a potential treatment for unresectable biliary RMS.

Isolation of the trail recruitment pheromone ofSolenopsis invicta

TheSolenopsis invicta trail pheromone is synthesized by the Dufour's gland and is released through the sting apparatus. The recruitment subcategory of theS. invicta trail pheromone was shown to be composed of a mixture of the orientation pheromone, (Z,E)-α-farnesene and an unidentified homosesquiterpene consisting of three rings and one double bond (C-1). C-1 is present in worker Dufour's glands at only 75 pg per worker equivalent. This is the first report that demonstrates that different exocrine products from the same gland control different subcategories of behavior related to mass recruitment.

Applicability of mode-coupling theory to polyisobutylene: a molecular dynamics simulation study

The applicability of Mode Coupling Theory (MCT) to the glass-forming polymer polyisobutylene (PIB) has been explored by using fully atomistic molecular dynamics simulations. MCT predictions for the so-called asymptotic regime have been successfully tested on the dynamic structure factor and the self-correlation function of PIB main-chain carbons calculated from the simulated cell. The factorization theorem and the time-temperature superposition principle are satisfied. A consistent fitting procedure of the simulation data to the MCT asymptotic power-laws predicted for the α-relaxation regime has delivered the dynamic exponents of the theory-in particular, the exponent parameter λ-the critical non-ergodicity parameters, and the critical temperature T(c). The obtained values of λ and T(c) agree, within the uncertainties involved in both studies, with those deduced from depolarized light scattering experiments [A. Kisliuk et al., J. Polym. Sci. Part B: Polym. Phys. 38, 2785 (2000)]. Both, λ and T(c)/T(g) values found for PIB are unusually large with respect to those commonly obtained in low molecular weight systems. Moreover, the high T(c)/T(g) value is compatible with a certain correlation of this parameter with the fragility in Angell's classification. Conversely, the value of λ is close to that reported for real polymers, simulated "realistic" polymers and simple polymer models with intramolecular barriers. In the framework of the MCT, such finding should be the signature of two different mechanisms for the glass-transition in real polymers: intermolecular packing and intramolecular barriers combined with chain connectivity.

The plant-associated Bacillus amyloliquefaciens strains MEP2 18 and ARP2 3 capable of producing the cyclic lipopeptides iturin or surfactin and fengycin are effective in biocontrol of sclerotinia stem rot disease

AIMS

This work was conducted to identify the antifungal compounds produced by two previously isolated Bacillus sp. strains: ARP(2) 3 and MEP(2) 18. Both strains were subjected to further analysis to determine their taxonomic position and to identify the compounds responsible for their antifungal activity as well as to evaluate the efficiency of these strains to control sclerotinia stem rot in soybean.

METHODS AND RESULTS

The antifungal compounds were isolated by acid precipitation of cell-free supernatants, purified by RP-HPLC and then tested for antagonistic activity against Sclerotinia sclerotiorum. Mass spectra from RP-HPLC eluted fractions showed the presence of surfactin C(15) , fengycins A (C(16) -C(17)) and B (C(16)) isoforms in supernatants from strain ARP(2) 3 cultures, whereas the major lipopeptide produced by strain MEP(2) 18 was iturin A C(15) . Alterations in mycelial morphology and sclerotial germination were observed in the presence of lipopeptides-containing supernatants from Bacillus strains cultures. Foliar application of Bacillus amyloliquefaciens strains on soybean plants prior to S. sclerotiorum infection resulted in significant protection against sclerotinia stem rot compared with noninoculated plants or plants inoculated with a nonlipopeptide-producing B. subtilis strain.

CONCLUSIONS

Both strains, renamed as B. amyloliquefaciens ARP(2) 3 and MEP(2) 18, were able to produce antifungal compounds belonging to the cyclic lipopeptide family. Our data suggest that the foliar application of lipopeptide-producing B. amyloliquefaciens strains could be a promising strategy for the management of sclerotinia stem rot in soybean.

SIGNIFICANCE AND IMPACT OF THE STUDY

Sclerotinia stem rot was ranked as one of the most severe soybean disease in Argentina and worldwide. The results of this study showed the potential of B. amyloliquefaciens strains ARP(2) 3 and MEP(2) 18 to control plant diseases caused by S. sclerotiorum.

Preliminary evidence for biologic activity of toceranib phosphate (Palladia(®)) in solid tumours

The purpose of this study was to provide an initial assessment of the potential biologic activity of toceranib phosphate (Palladia®, Pfizer Animal Health, Madison, NJ, USA) in select solid tumours in dogs. Cases in which toceranib was used to treat dogs with apocrine gland anal sac adenocarcinoma (AGASACA), metastatic osteosarcoma (OSA), thyroid carcinoma, head and neck carcinoma and nasal carcinoma were included. Clinical benefit (CB) was observed in 63/85 (74%) dogs including 28/32 AGASACA [8 partial response (PR), 20 stable disease (SD)], 11/23 OSAs (1 PR and 10 SD), 12/15 thyroid carcinomas (4 PR and 8 SD), 7/8 head and neck carcinomas [1 complete response (CR), 5 PR and 1 SD] and 5/7 (1 CR and 4 SD) nasal carcinomas. For dogs experiencing CB, the median dose of toceranib was 2.8 mg kg(-1) , 36/63 (58.7%) were dosed on a Monday/Wednesday/Friday basis and 47/63 (74.6%) were treated 4 months or longer. Although these data provide preliminary evidence that toceranib exhibits CB in dogs with certain solid tumours, future prospective studies are necessary to define its true activity.

Hyperammonemia and neonatal cardiac failure

Severe hyperammonemia (hyperNH3) in neonatal cardiac failure after cardiac surgery is rare. We report a case of a 2470-g female infant born at the week 37 of gestation with complex congenital heart disease (truncus arteriosus type III, interrupted aortic arch and tricuspid valve insufficiency) and hemodynamically non-significant intrahepatic arterio-venous malformation. She developed hyperNH3 (highest NH3 blood level: 467 µmol/L) without severe liver failure (INR of 1.9). The origin of the hyperNH3 was multifactorial including limited capacity of liver detoxification function due to congenital porto-caval shunt, liver ischemia, excessive protein intake and increased protein catabolic rate. HyperNH3 treatment partially succeeded in decreasing ammonia level and included discontinuation of protein intake, administration of phenylacetate and sodium benzoate. This case highlights the fact that NH3 detoxification by the liver has limitations for a neonate with multifactorial causes that decrease liver perfusion.

The free volume of poly(vinyl methylether) as computed in a wide temperature range and at length scales up to the nanoregion

In the present work, we focus on the free volume evaluations from different points of view, including the aspect of probe sizes, temperature, and cavity threshold. The free volume structure is analyzed on structures of poly(vinyl methylether) prepared by fully atomistic molecular dynamics. At first, the temperature behavior of an overall free volume and a free volume separated into individual cavities is shown. The origin of large free volume cavities is explained. A complex view on the cavity number is provided, while a complicated behavior previously observed is now explained. The number of large cavities remained almost constant with the temperature. Oppositely, the number of small cavities related to the atomic packing changes with temperature in a distinct way for glassy and supercooled regions. The cavity number maxima determine a percolation threshold according to percolation theory. The change in polymer properties with temperature can be related to a percolation of the free volume according to the free volume theory, when proper probe radii ∼0.8 Å are used for its observation. A construction of probabilistic distribution of free volume sizes is suggested. The free volume distributions reported here are bimodal. The bimodal character is explained by two different packings--atomic and segmental--forming a prepeak and a main peak on the distribution. Further attention is dedicated to comparisons of the computed free volume sizes and the ortho-positronium (o-Ps) lifetimes. The prepeak of the free volume distribution is probably unseen by o-Ps because of a cavity threshold limit. The effect of the shape factor on the computed o-Ps lifetimes is tested. The quasicavities obtained by redistributing the free volume maintain the ratio of the main dimensions with temperature. Finally, novel data on the cavity environment are provided, while it is suggested how these can be useful with the recent developments in the positron annihilation methods. The coordination number of large cavities with the polymer segments is around 1, as predicted in the free volume theory. Similarly to the percolation and the cavity number, the coordination number exhibits a change when explored by a suitable probe radius ∼0.8 Å. The insightful visualizations showed properties of interest investigated within the actual work.

CONSORT adoption and quality of reporting of randomized controlled trials: a systematic analysis in two dermatology journals

BACKGROUND

CONSORT (Consolidated Standards for Reporting Trials) guidelines were constructed to ensure optimal reporting quality of randomized controlled trials (RCTs).

OBJECTIVES

To determine the effect of the adoption of CONSORT on the reporting quality of RCTs, we performed a systematic evaluation of RCTs published in two dermatology journals pre- and post-CONSORT adoption.

METHODS

The journals selected for the study were the Journal of the American Academy of Dermatology and the British Journal of Dermatology. We selected RCTs published in 1997 and 2006 using both Medline and hand searching. The following critical CONSORT criteria were recorded: sample size, type of disease studied, type of control, single-centre or multicentre study, type of funding, blinding, methods and type of randomization, definition of a primary endpoint, justification for sample size selection and power calculation, population for analysis, and adequacy of group comparison. A multivariable analysis was conducted to determine factors associated with optimal reporting quality.

RESULTS

In total, 98 studies were included. Improvement in reporting quality was evident for the specification of the randomization method (20% in 1997 vs. 45% in 2006, P < 0.01) and for the justification of sample size (22% in 1997 vs. 43% in 2006, P = 0.027). The percentage of studies with optimal reporting quality increased from 11% in 1997 to 28% in 2006 (P = 0.03). Factors significantly associated with a good methodological quality were pharmaceutical industry funding and publication in 2006 vs. 1997.

CONCLUSIONS

There is a need to improve the reporting quality of RCTs published in dermatology journals.