Closed-incision negative-pressure wound therapy reduces superficial surgical site infections after open colon surgery: an NSQIP Colectomy Study.

BACKGROUND: The use of closed-incision negative-pressure wound therapy (iNPWT) has increased in the last decade across surgical fields, including colectomy. AIM: To compare postoperative outcomes associated with use of iNPWT following open colectomy from a large national database. METHODS: A retrospective review of patients who underwent operations from 2015 to 2020 was performed using the National Surgical Quality Improvement Program (NSQIP) Targeted Colectomy Database. Intraoperative placement of iNPWT was identified in patients undergoing open abdominal operations with closure of all wound layers including skin. Propensity score matching was performed to define a control group who underwent closure of all wound layers without iNPWT. Patients were matched in a 1:4 (iNPWT vs control) ratio and postoperative rates of superficial, deep and organ-space surgical site infection (SSI), wound disruption, and readmission. FINDINGS: A matched cohort of 1884 was selected. Patients with iNPWT had longer median operative time (170 (interquartile range: 129-232) vs 161 (114-226) min; P<0.05). Compared to patients without iNPWT, patients with iNPWT experienced a lower rate of 30-day superficial incisional SSI (3% vs 7%; P<0.05) and readmissions (10% vs 14%; P<0.05). iNPWT did not decrease risk of deep SSI, organ-space SSI, or wound disruption. CONCLUSION: Although there is a slightly increased operative time, utilization of iNPWT in open colectomy is associated with lower odds of superficial SSI and 30-day readmission. This suggests that iNPWT should be routinely utilized in open colon surgery to improve patient outcomes.

Staged abdominal wall reconstruction in the setting of complex gastrointestinal reconstruction.

PURPOSE: Literature on one- versus two-staged abdominal wall reconstruction (AWR) with complex gastrointestinal reconstruction (GIR) is limited to single-arm case series with a focus on patients who complete all planned stages. Herein, we describe our experience with both one- and two-staged approaches to AWR/GIR, with attention to those who did not complete both intended stages. METHODS: A retrospective review of prospectively collected data was conducted to identify patients who underwent a one- or two-stage approach to GIR/AWR from 2013 to 2020. The one-stage approach included GIR and definitive sublay mesh herniorrhaphy. The two-stage approach included Stage 1 (S1)-GIR and non-definitive herniorrhaphy and Stage 2 (S2)-definitive sublay mesh herniorrhaphy. RESULTS: Fifty-four patients underwent GIR/AWR: 20 (37.0%) underwent a planned 1-stage operation while 34 (63.0%) underwent S1 of a planned 2-stage approach. Patients assigned to the 2-stage approach were more likely to be smokers, have a history of mesh infection, have an enterocutaneous fistula, and a contaminated wound class (p<0.05). Of the 34 patients who underwent S1, 12 (35.3%) completed S2 during the mean follow-up period of 44 months while 22 (64.7%) did not complete S2. Of these, 10 (45.5%) developed hernia recurrence but did not undergo S2 secondary to elective nonoperative management (40%), pending preoperative optimization (30%), additional complex GIR (10%), hernia-related incarceration requiring emergent surgery (10%), or unrelated death (10%). No differences in outcome including SSI, SSO, readmission, and recurrence were noted between the 12 patients who completed the two-stage approach and the 20 patients who completed a one-stage approach, despite increased risk factors for complications in the 2-stage group (p>0.05). CONCLUSION: Planned two-stage operations for GIR/AWR may distribute operative complexity and post-operative morbidity into separate surgical interventions. However, many patients may never undergo the intended definitive S2 herniorrhaphy. Future evaluation of 1- versus 2-stage GIR/AWR is needed to clarify indications for each approach. This work must also consider the frequent deviations from intended clinical course demonstrated in this study.

Safety, Efficacy and Distribution of Doxorubicin Loaded Radiopaque Beads in Chemoembolization in Intermediate Stage Hepatocellular Carcinoma (HCC) with Correlation with Local Response.

PURPOSE: The primary objectives of this study were to evaluate safety, and efficacy of Transarterial Chemoembolization (TACE) using doxorubicin-loaded radiopaque microspheres (DC Bead LUMI™) for the treatment of early and intermediate stage Hepatocellular Carcinoma (HCC) not amenable for curative treatments. Distribution of the microspheres was correlated with results post embolization. MATERIALS AND METHODS: This was a prospective, single arm, open label study. The primary outcome measures were distribution of the radiopaque microspheres as showed by computerized tomography (CT) and local response measured by modified Response Evaluation Criteria (mRECIST) after Magnetic Resonance Imaging (MRI). Secondary measures were Time to Progression (TTP) and Overall Survival (OS). RESULTS: Fifty patients were enrolled over 36 months. Median age was 69.0 years; mean sum of target lesions diameters was 78.6 ± 36.8 mm. There were no Grade 4 or 5 adverse events (AEs). At 6 months Complete Response (CR) (18%), Partial Response (PR) (62%), Objective Response OR (80%) and Stable Disease (SD) (20%) were recorded. Before embolization, Diffusion Weighted Imaging (DWI) showed high signal (restricted diffusion). Post procedure, patients with dense deposition (< 5 mm distance of microsphere aggregations) showed 100% absence of enhancement and no restriction in 30.6%. Median TTP was 8.3 months. TTP for patients with CR was 13.3 months and 7.2 and 5.6 for PR and SD, respectively. At 6 and 36 months, survival was 94% and 34%, respectively. CONCLUSION: DC Bead LUMI™ is well tolerated and effective in early and intermediate stage HCC with maximal necrosis obtained in dense deposition in the target.

Standards of Care for the Health of Transgender and Gender Diverse People, Version 8.

Background: Transgender healthcare is a rapidly evolving interdisciplinary field. In the last decade, there has been an unprecedented increase in the number and visibility of transgender and gender diverse (TGD) people seeking support and gender-affirming medical treatment in parallel with a significant rise in the scientific literature in this area. The World Professional Association for Transgender Health (WPATH) is an international, multidisciplinary, professional association whose mission is to promote evidence-based care, education, research, public policy, and respect in transgender health. One of the main functions of WPATH is to promote the highest standards of health care for TGD people through the Standards of Care (SOC). The SOC was initially developed in 1979 and the last version (SOC-7) was published in 2012. In view of the increasing scientific evidence, WPATH commissioned a new version of the Standards of Care, the SOC-8. Aim: The overall goal of SOC-8 is to provide health care professionals (HCPs) with clinical guidance to assist TGD people in accessing safe and effective pathways to achieving lasting personal comfort with their gendered selves with the aim of optimizing their overall physical health, psychological well-being, and self-fulfillment. Methods: The SOC-8 is based on the best available science and expert professional consensus in transgender health. International professionals and stakeholders were selected to serve on the SOC-8 committee. Recommendation statements were developed based on data derived from independent systematic literature reviews, where available, background reviews and expert opinions. Grading of recommendations was based on the available evidence supporting interventions, a discussion of risks and harms, as well as the feasibility and acceptability within different contexts and country settings. Results: A total of 18 chapters were developed as part of the SOC-8. They contain recommendations for health care professionals who provide care and treatment for TGD people. Each of the recommendations is followed by explanatory text with relevant references. General areas related to transgender health are covered in the chapters Terminology, Global Applicability, Population Estimates, and Education. The chapters developed for the diverse population of TGD people include Assessment of Adults, Adolescents, Children, Nonbinary, Eunuchs, and Intersex Individuals, and people living in Institutional Environments. Finally, the chapters related to gender-affirming treatment are Hormone Therapy, Surgery and Postoperative Care, Voice and Communication, Primary Care, Reproductive Health, Sexual Health, and Mental Health. Conclusions: The SOC-8 guidelines are intended to be flexible to meet the diverse health care needs of TGD people globally. While adaptable, they offer standards for promoting optimal health care and guidance for the treatment of people experiencing gender incongruence. As in all previous versions of the SOC, the criteria set forth in this document for gender-affirming medical interventions are clinical guidelines; individual health care professionals and programs may modify these in consultation with the TGD person.

Field-induced vortex-like textures as a probe of the critical line in reentrant spin glasses.

We study the evolution of the low-temperature field-induced magnetic defects observed under an applied magnetic field in a series of frustrated amorphous ferromagnets (Fe[Formula: see text]Mn[Formula: see text])[Formula: see text]P[Formula: see text]B[Formula: see text]Al[Formula: see text] ("a-Fe[Formula: see text]Mn[Formula: see text]"). Combining small-angle neutron scattering and Monte Carlo simulations, we show that the morphology of these defects resemble that of quasi-bidimensional spin vortices. They are observed in the so-called "reentrant" spin-glass (RSG) phase, up to the critical concentration [Formula: see text] which separates the RSG and "true" spin glass (SG) within the low temperature part of the magnetic phase diagram of a-Fe1-xMnx. These textures systematically decrease in size with increasing magnetic field or decreasing the average exchange interaction, and they finally disappear in the SG sample ([Formula: see text]), being replaced by field-induced correlations over finite length scales. We argue that the study of these nanoscopic defects could be used to probe the critical line between the RSG and SG phases.

Geometry relaxation-mediated localization and delocalization of excitons in organic semiconductors: A quantum chemical study.

Photo-induced relaxation processes leading to excimer formations or other traps are in the focus of many investigations of optoelectronic materials because they severely affect the efficiencies of corresponding devices. Such relaxation effects comprise inter-monomer distortions in which the orientations of the monomer change with respect to each other, whereas intra-monomer distortions are variations in the geometry of single monomers. Such distortions are generally neglected in quantum chemical investigations of organic dye aggregates due to the accompanied high computational costs. In the present study, we investigate their relevance using perylene-bisimide dimers and diindenoperylene tetramers as model systems. Our calculations underline the importance of intra-monomer distortions on the shape of the potential energy surfaces as a function of the coupling between the monomers. The latter is shown to depend strongly on the electronic state under consideration. In particular, it differs between the first and second excited state of the aggregate. Additionally, the magnitude of the geometrical relaxation decreases if the exciton is delocalized over an increasing number of monomers. For the interpretation of the vibronic coupling model, pseudo-Jahn-Teller or Marcus theory can be employed. In the first part of this paper, we establish the accuracy of density functional theory-based approaches for the prediction of vibrationally resolved absorption spectra of organic semiconductors. These investigations underline the accuracy of those approaches although shortcomings become obvious as well. These calculations also indicate the strength of intra-monomer relaxation effects.

Contact killing and antimicrobial properties of copper.

With the emergence of antibiotic resistance, the interest for antimicrobial agents has recently increased again in public health. Copper was recognized in 2008 by the United States Environmental Protection Agency (EPA) as the first metallic antimicrobial agent. This led to many investigations of the various properties of copper as an antibacterial, antifungal and antiviral agent. This review summarizes the latest findings about 'contact killing', the mechanism of action of copper nanoparticles and the different ways micro-organisms develop resistance to copper.

Nanoscale Structure of the Oil-Water Interface.

X-ray reflectivity (XR) and atomistic molecular dynamics (MD) simulations, carried out to determine the structure of the oil-water interface, provide new insight into the simplest liquid-liquid interface. For several oils (hexane, dodecane, and hexadecane) the XR shows very good agreement with a monotonic interface-normal electron density profile (EDP) broadened only by capillary waves. Similar agreement is also found for an EDP including a sub-Å thick electron depletion layer separating the oil and the water. The XR and MD derived depletions are much smaller than reported for the interface between solid-supported hydrophobic monolayers and water.

Hydrogel microstructure live-cell array for multiplexed analyses of cancer stem cells, tumor heterogeneity and differential drug response at single-element resolution.

Specific phenotypic subpopulations of cancer stem cells (CSCs) are responsible for tumor development, production of heterogeneous differentiated tumor mass, metastasis, and resistance to therapies. The development of therapeutic approaches based on targeting rare CSCs has been limited partially due to the lack of appropriate experimental models and measurement approaches. The current study presents new tools and methodologies based on a hydrogel microstructure array (HMA) for identification and multiplex analyses of CSCs. Low-melt agarose integrated with type I collagen, a major component of the extracellular matrix (ECM), was used to form a solid hydrogel array with natural non-adhesive characteristics and high optical quality. The array contained thousands of individual pyramidal shaped, nanoliter-volume micro-chambers (MCs), allowing concomitant generation and measurement of large populations of free-floating CSC spheroids from single cells, each in an individual micro-chamber (MC). The optical live cell platform, based on an imaging plate patterned with HMA, was validated using CSC-enriched prostate and colon cancer cell lines. The HMA methodology and quantitative image analysis at single-element resolution clearly demonstrates several levels of tumor cell heterogeneity, including morphological and phenotypic variability, differences in proliferation capacity and in drug response. Moreover, the system facilitates real-time examination of single stem cell (SC) fate, as well as drug-induced alteration in expression of stemness markers. The technology may be applicable in personalized cancer treatment, including multiplex ex vivo analysis of heterogeneous patient-derived tumor specimens, precise detection and characterization of potentially dangerous cell phenotypes, and for representative evaluation of drug sensitivity of CSCs and other types of tumor cells.

The Complex Dance of the Two Conformers of Bis(trifluoromethanesulfonyl)imide as a Function of Pressure and Temperature.

Absorbance spectra of two ionic liquids, the short alkyl chain N-trimethyl-N-propylammonium bis(trifluoromethanesulfonyl)imide (TMPA-TFSI) and the longer chain N-trimethyl-N-hexylammonium bis(trifluoromethanesulfonyl)imide (TMHA-TFSI) are reported as a function of pressure and temperature. The occurrence of various phase transitions is evidenced by the changes in the relative concentration of the cisoid and transoid conformers of their common TFSI anion. The infrared spectrum of TMPA-TFSI was measured at 300 K with an applied pressure varying over the 0-5 GPa range. Above 0.2 GPa only the trans conformer is detected, suggesting the occurrence of a pressure induced crystallization. When pressure is applied to TMHA-TFSI at T = 310 K, both TFSI conformers subsist up to ∼11 GPa. However, the clear change of their intensity ratio observed around 2 GPa, suggests the onset of a glass phase as supported by measurements carried out at 4.2 GPa along a cooling/heating cycle. A careful analysis of the spectra collected along different p-T thermodynamic paths shows the occurrence of a cold crystallization at 295 K on heating from 139 K along the p = 0.5 GPa isobar. The rich phase diagrams of the two ionic liquids is the result of the competition among the anion-cation intermolecular interactions, the lower energy of trans-TFSI with respect to cis-TFSI and the smaller volume of cis-TFSI with respect to trans-TFSI.

Multifocal splenic abscesses in immunocompetent adult due to cat-scratch disease.

BACKGROUND: Cat-scratch disease is caused by Bartonella henselae and transmitted to humans via the cats. Patients usually present with cutaneous lesions, regional lymphadenopathy and a brief period of fever. CASE REPORT: We report a rare case of an isolated splenic cat-scratch disease in an immunocompetent 27-year-old woman who presented with prolonged fever and multifocal splenic lesions. The patient was treated successfully with a long course of antibiotics. CONCLUSION: Isolated splenic lesions and fever is a rare manifestation of the cat-scratch disease. There is need of high suspicion index by the physicians to diagnose the disease promptly without invasive methods. Hippokratia 2016, 20(4): 306-308.

Divergent effects of RIP1 or RIP3 blockade in murine models of acute liver injury.

Necroptosis is a recently described Caspase 8-independent method of cell death that denotes organized cellular necrosis. The roles of RIP1 and RIP3 in mediating hepatocyte death from acute liver injury are incompletely defined. Effects of necroptosis blockade were studied by separately targeting RIP1 and RIP3 in diverse murine models of acute liver injury. Blockade of necroptosis had disparate effects on disease outcome depending on the precise etiology of liver injury and component of the necrosome targeted. In ConA-induced autoimmune hepatitis, RIP3 deletion was protective, whereas RIP1 inhibition exacerbated disease, accelerated animal death, and was associated with increased hepatocyte apoptosis. Conversely, in acetaminophen-mediated liver injury, blockade of either RIP1 or RIP3 was protective and was associated with lower NLRP3 inflammasome activation. Our work highlights the fact that diverse modes of acute liver injury have differing requirements for RIP1 and RIP3; moreover, within a single injury model, RIP1 and RIP3 blockade can have diametrically opposite effects on tissue damage, suggesting that interference with distinct components of the necrosome must be considered separately.

Evaluation of a biofilm formation by Desulfovibrio fairfieldensis on titanium implants.

UNLABELLED: The aim of this study was to assess the capabilities of Desulfovibrio fairfieldensis to colonize the grade 4 titanium coupons (modSLA) used in dental implants. The effect of ampicillin, which is known to be a poorly penetrating agent in the matrix biofilm, was also compared with planktonic and sessile cells. The modSLA colonization by bacteria in KNO3 (0.05 mol l(-1)) and culture media (DSM 63 and fetal bovine serum) was determined by direct cell counts and field emission electronic microscopy. The surface of titanium (Ti) coupons was characterized by scanning electron microscopy and by Raman spectroscopy. Cells, mainly located in surface pores of modSLA coupons, appeared to be wrapped in a polymeric-like structure. The initial apparent rates of adhesion varied from 3 × 10(6) to 30 × 10(6) cells cm(-2) h(-1), and a plateau was reached at 1 day, regardless of the incubation medium. No cells have significantly adhered to polished Ti, and a minority was found on massive Ti. Finally, cells trapped on the modSLA surface were not lysed by ampicillin contrary to planktonic cells. Des. fairfieldensis is therefore able to colonize the rough surface of modSLA implant through a physical trapping in the microporosity of the surface, where they can produce a biofilm-like structure to improve their resistance to ampicillin. SIGNIFICANCE AND IMPACT OF THE STUDY: Desulfovibrio fairfieldensis is one of the most relevant sulphate-reducing bacteria of the human oral cavity suspected to be involved in peri-implantitis and implant corrosion. This study demonstrates for the first time that Des. fairfieldensis is able to initiate the formation of a biofilm-like structure on the microstructured titanium coupons used in dental implants and that it improves its resistance to antibiotic treatment. It gives new insight to understand the capacity of this opportunistic pathogen to colonize implant surfaces and to resist to biocide treatments.

Pseudorotational epitaxy of self-assembled octadecyltrichlorosilane monolayers on sapphire (0001).

The structure of octadecyltrichlorosilane self-assembled monolayers (SAMs) on sapphire (0001) was studied by Å-resolution surface-specific x-ray scattering methods. The monolayer was found to consist of three sublayers where the outermost layer corresponds to vertically oriented, closely packed alkyl tails. Laterally, the monolayer is hexagonally packed and exhibits pseudorotational epitaxy to the sapphire, manifested by a broad scattering peak at zero relative azimuthal rotation, with long powderlike tails. The lattice mismatch of ∼ 1%-3% to the sapphire's and the different length scale introduced by the lateral Si-O-Si bonding prohibit positional epitaxy. However, the substrate induces an intriguing increase in the crystalline coherence length of the SAM's powderlike crystallites when rotationally aligned with the sapphire's lattice. The increase correlates well with the rotational dependence of the separation of corresponding substrate-monolayer lattice sites.

The role of tenofovir in preventing and treating hepatitis B virus (HBV) reactivation in immunosuppressed patients. A real life experience from a tertiary center.

INTRODUCTION/AIM: Patients who present HBV reactivation during immunosuppressive treatment are prone to develop life threatening decompensation of the liver function, therefore prophylaxis and treatment are strongly recommended. So far there are no data regarding the role of tenofovir in this context. Therefore, the aim of our study was to describe our "real life" experience with the use of tenofovir (TDF) in patients who underwent immunosuppressive treatment. RESULTS: 38 patients with immunosuppression received antiviral treatment with tenofovir (25 patients as prophylaxis and 13 patients as treatment of HBV reactivation). In all 25 patients in whom prophylactic treatment with tenofovir was administered no HBV flare occurred during immunosuppression and the levels of serum HBV-DNA became or remained undetectable during the follow up period (mean follow up 17.2 months, range 6-54). One patient experienced HBsAg seroconversion. In the 13 patients who exhibited HBV reactivation TDF treatment resulted in complete biochemical and virological response within 6 months except two patients with high pretreatment HBV-DNA levels who became HBV-DNA negative at 9 months. No exacerbation of liver disease or liver related death has been observed. One patient who presented with decompensated cirrhosis during HBV reactivation returned into a compensated state after treatment. No side effects of tenofovir have been documented. CONCLUSION: Tenofovir seems to be highly effective and safe in the prophylaxis and rescue treatment of HBV reactivation in patients who receive immunosuppression therapy.

Donut-shaped chambers for analysis of biochemical processes at the cellular and subcellular levels.

In order to study cell-cell variation with respect to enzymatic activity, individual live cell analysis should be complemented by measurement of single cell content in a biomimetic environment on a cellular scale arrangement. This is a challenging endeavor due to the small volume of a single cell, the low number of target molecules and cell motility. Micro-arrayed donut-shaped chambers (DSCs) of femtoliter (fL), picoliter (pL), and nanoliter (nL) volumes have been developed and produced for the analysis of biochemical reaction at the molecular, cellular and multicellular levels, respectively. DSCs are micro-arrayed, miniature vessels, in which each chamber acts as an individual isolated reaction compartment. Individual live cells can settle in the pL and nL DSCs, share the same space and be monitored under the microscope in a noninvasive, time-resolved manner. Following cell lysis and chamber sealing, invasive kinetic measurement based on cell content is achieved for the same individual cells. The fL chambers are used for the analysis of the same enzyme reaction at the molecular level. The various DSCs were used in this proof-of-principle work to analyze the reaction of intracellular esterase in both primary and cell line immune cell populations. These unique DSC arrays are easy to manufacture and offer an inexpensive and simple operating system for biochemical reaction measurement of numerous single cells used in various practical applications.

The usefulness of transient elastography in the assessment of patients with HBeAg-negative chronic hepatitis B virus infection.

Histological severity is often mandatory for the management of HBeAg-negative chronic HBV patients. We evaluated the performance of transient elastography (TE) in this setting. We included 357 untreated HBeAg-negative patients with ≥ 1 reliable liver stiffness measurement (LSM-kPa) by TE: 182 inactive carriers with HBV-DNA < 2000 (n = 139) or 2000-19 999 IU/mL (n = 43) and 175 patients with chronic hepatitis B (CHB). In carriers, HBV-DNA > 2000 and/or LSM > 6.5 were considered as biopsy indications. LSMs did not differ between carriers with low and high viremia, but were lower in carriers than in patients with CHB (5.8 ± 1.7 vs 9.0 ± 5.6, P < 0.001) offering moderate differentiation between these two groups (AUROC: 0.705). LSMs did not change significantly in carriers after 16 (12-24) months. In carriers with a liver biopsy, Ishak's staging scores were similar between cased with low and high viremia but higher in cases with LSM > 6.5 than ≤ 6.5 kPa. Moderate fibrosis (stages: 2-3) was detected in 0/10 carriers with only HBV-DNA > 2000 IU/mL, 2/10 (20%) carriers with only LSM > 6.5 and 5/10 (50%) carriers with both HBV-DNA > 2000 and LSM > 6.5 (P = 0.009). In patients with CHB, LSMs correlated significantly with grading and staging scores and offered excellent accuracy for ≥ moderate, ≥ severe fibrosis or cirrhosis (AUROC ≥ 0.919-0.950). TE can be helpful for the noninvasive assessment of HBeAg-negative chronic HBV patients. In conclusion, LSMs offer excellent accuracy for fibrosis severity in HBeAg-negative patients with CHB and can identify carriers with high risk of moderate fibrosis, which may be present in up to 35% of carriers with LSM > 6.5 kPa and 50% of carriers with LSM > 6.5 kPa and HBV-DNA > 2000 IU/mL.

Peri-conceptional obesogenic exposure induces sex-specific programming of disease susceptibilities in adult mouse offspring.

Vulnerability of the fetus upon maternal obesity can potentially occur during all developmental phases. We aimed at elaborating longer-term health outcomes of fetal overnutrition during the earliest stages of development. We utilized Naval Medical Research Institute (NMRI) mice to induce pre-conceptional and gestational obesity and followed offspring outcomes in the absence of any postnatal obesogenic influences. Male adult offspring developed overweight, insulin resistance, hyperleptinemia, hyperuricemia and hepatic steatosis; all these features were not observed in females. Instead, they showed impaired fasting glucose and a reduced fat mass and adipocyte size. Influences of the interaction of maternal diet∗sex concerned offspring genes involved in fatty liver disease, lipid droplet size regulation and fat mass expansion. These data suggest that a peri-conceptional obesogenic exposure is sufficient to shape offspring gene expression patterns and health outcomes in a sex- and organ-specific manner, indicating varying developmental vulnerabilities between sexes towards metabolic disease in response to maternal overnutrition.

Cirrhosis but not neutropenia is associated with the development of infection in patients with chronic hepatitis C undergoing treatment with pegylated interferon-alpha and ribavirin.

Peginterferon-alpha (PegIFNa) frequently causes neutropenia, mainly due to bone marrow suppression. The aim of this study was to explore factors that are associated with infections during antiviral treatment. We analysed data from 275 chronic hepatitis C (CHC) patients with compensated liver disease who underwent 318 courses of PegIFNa and ribavirin. Neutropenia was defined as neutrophils <1000 cells/µL. Mean leucocytes count significantly decreased from baseline to treatment nadir (7081 ± 2182 vs 3293 ± 1331 cells/µL, P < 0.001), while neutropenia was observed in 32% during treatment. Thirty-one infections were observed. The incidence rate for infection was assessed at 1.46 infections per 100 person-months of therapy. The hazard rate for infection did not correlate with the neutrophils' nadir or the decrease in white blood cells. In multivariate Cox's regression analysis, cirrhosis was the only factor that was significantly associated with the occurrence of infection. Our data show that the development of bacterial infections during treatment with PegIFNa and ribavirin in patients with compensated CHC is not associated with reduction or the nadir of white cells or neutrophil counts. Baseline cirrhosis is the only factor related with infection during treatment. The common practice of dose adjustment or discontinuation of interferon should be revised; careful assessment of liver damage before therapy and close monitoring during therapy are essential in all patients receiving interferon-based regimes, to minimize the detrimental consequences of infections.

High-resolution tomography study of the porosity of three restorative resin composites.

OBJECTIVES: The aim of this study was to analyze the porosity of three photopolymerizable resin composites: one high-viscous resin composite (Filtek™ P60®, 3 M™ ESPE™), one moderate-viscosity resin composite (Grandio®, VOCO™), and one low-viscous resin composite (Filtek™ Supreme XTE®, 3 M™ ESPE™). MATERIALS AND METHODS: A total of 36 cylindrical samples with a height of 2 mm and a diameter of 2 mm were prepared using PTFE molds. Eighteen cylinders were prepared by two incremental applications of 1 mm into the molds, then polymerized (group 1). For the other 18 samples (group 2), the first increment was polymerized before the second addition was made. The average porosity percentage and the average porosity volume were evaluated by high-resolution tomography (Nanotom M® - Phoenix X-Ray(TM), Wunstorf, Germany). The impact of incremental applications in terms of porosity was also evaluated. RESULTS: Irrespective of the protocol used, the low viscous material presented an average porosity percentage and an average porosity volume significantly greater than those of the other materials. Incremental application (group 2 samples) led to an increase in the average porosity percentage and volume irrespective of the material compared to the group 1 samples. CONCLUSIONS: High-resolution tomography appeared to be a particularly suitable tool for studying the porosity of resin composites. The viscosity and the handling of these materials seemed to be influential factors on their porosity. CLINICAL RELEVANCE: The presence of porosities in dental resin composites remains an objective reality, especially with low-viscous resin composites. Since the intrinsic porosity of the materials can be neither controlled nor modified by the operator, rigorous and iterative clinical protocols still remain the best way to limit inclusion of porosities in the resin composites.