Biogeochemical and oceanographic conditions provide insights about current status of an Antarctic fjord affected by relatively slow glacial retreat.

Understand the origin, transport, and character of organic matter entering Antarctic fjords is essential as they are major components of the global carbon cycle and budget. Macromolecular pools of particulate organic matter, bulk organic geochemistry, major and trace elements in surface sediments from Collins Bay were analysed as source indicators. Oceanographic conditions, bathymetry (multibeam) and grain size were considered as environmental controlling factors. Sediment samples were taken with a van Veen grab, during the ANTAR XXV Peruvian expedition (February 2018), onboard the R/V "BAP Carrasco" from the Peruvian Navy. Biopolymeric composition revealed the predominance of fresh marine protein-rich organic matter in the seafloor of Collins Bay, denoting high quality food resource for marine benthic heterotrophs. Based on Igeo values (between 0 and 1) Collins Bay can be considered unpolluted with natural levels of As, Cd, Cr, Cu, Fe, Mn, Ni, Pb and Zn. Distribution of most of these elements with a gradient of decrease from the shallow inner fjord towards the outer deepest fjord, suggest their association with the deposition of detrital material and lithogenic particles supplied by Collins Glacier frontal ablation and runoff. This first comprehensive baseline information would assist in interpreting downcore sedimentary reconstructions and future climate-induce changes.

Retinal function after intravitreal injection of autologous bone marrow-derived mesenchymal stromal cells in advanced glaucoma.

PURPOSE: To report electroretinographic (ERG) findings in advanced glaucoma treated with a single intravitreal injection of bone marrow-derived mesenchymal stem cells (MSCs). METHODS: Intravitreal injection of autologous MSCs (1 × 106 cells) was performed in 2 eyes from 2 patients with open-angle glaucoma in advanced stage of optic neuropathy (ClinicalTrials.gov, NCT02330978, 01.05.2015): cup/disk ratio worse than 0.9, visual field mean deviation index lower than - 15 dB, visual acuity of light perception, but controlled intraocular pressure. ERG tests were recorded at baseline and week 1, 4 and 48 after injection, using DTL electrodes following the ISCEV standard: After dark adaptation, ERG was elicited using white flashes of 0.01 cd.s/m2 and 3.0 cd.s/m2, followed by 10-min light adaptation (30 cd/m2) and stimuli of 3.0 cd.s/m2 and 30 Hz flicker. RESULTS: Patients did not show improvement on visual acuity or visual field after treatment. At baseline, ERG responses showed typical findings for advanced glaucoma, with a- and b-wave amplitude and latency within normative range, but reduced photopic negative responses. No noteworthy changes were observed on ERG responses for both cases up to 1 week after treatment, but at day 15, one patient showed retinal detachment with proliferative vitreoretinopathy and was removed from the trial. The other patient kept ERG responses stable throughout study period. CONCLUSION: Although no ERG response changes were observed after MSCs injection in one case, the complication observed on the second one, along with the lack of visual function improvement, warrants further studies involving modified MSCs to treat ocular disorders, including glaucoma. TRIAL REGISTRATION: ClinicalTrials.gov, NCT02330978- missed in pdf.

Bevacizumab versus triamcinolone for persistent diabetic macular edema: a randomized clinical trial.

PURPOSE: To evaluate 24-week visual acuity and anatomic outcomes of two "pro re nata" (prn) treatment strategies (intravitreal bevacizumab [IVB] prn versus intravitreal triamcinolone acetonide [IVT] prn) in patients with persistent diabetic macular edema (pDME) after 24 weeks of prn-IVB. METHODS: One hundred eyes with center-involving DME were enrolled and treated with prn-IVB for 24 weeks; at week 24, eyes with pDME (central subfield thickness [CST] on spectral domain optical coherence tomography > 300 µm) were randomized to IVB monthly prn (group I; prn-IVB) or IVT every 3 months prn (group II; prn-IVT) and eyes in which the CST was ≤ 300 µm were assigned to continue prn-IVB (group III). RESULTS: Seventy-four eyes completed a 48-week study period. At week 24, 65 (79.3%) eyes still had DME with CST > 300 µm and, therefore, were randomized to prn-IVB (group I, n = 33) or prn-IVT (group II, n = 32); the remaining 17 (20.7%) eyes had CST ≤ 300 µm and were assigned to continued treatment with prn-IVB (group III). At baseline, mean CST (µm) ± standard error of the mean (SEM) was 447.2 ± 24.4, 478.0 ± 19.7, and 386.0 ± 21.0 in groups I, II, and III, respectively (p > 0.05). At week 48, there was no significant difference in mean CST between groups I and II (369.9 ± 23.3 and 426.0 ± 26.1, respectively; p = 0.9995). A significant reduction in mean CST, compared with baseline, was noted at weeks 28 (p = 0.0002) and 44 (p = 0.0002) in group II. Group I did not show a significant reduction in mean CST compared with baseline at any study visit. There were no significant differences in mean CST between groups I and II at any study visit. At baseline, mean ± SEM best-corrected visual acuity (BCVA) (logMAR) was 0.50 ± 0.00, 0.60 ± 0.10, and 0.50 ± 0.10 in groups I, II, and III, respectively (p > 0.05). At week 48, there was no statistically significant difference in mean BCVA between groups I and II (0.50 ± 0.10 and 0.80 ± 0.10, respectively; p = 0.4473). There was no significant improvement in mean BCVA, as compared with baseline, at any study follow-up visit in any of the groups. Group II demonstrated significantly lower BCVA after 24 weeks of IVT (at week 48) compared with baseline (p = 0.0435). There was no significant difference in mean BCVA between groups I and II at any time-point. CONCLUSION: In eyes with pDME after 24 weeks of treatment with prn-IVB, there was no difference between continued treatment with prn-IVB versus a treatment switch to prn-IVT with respect to mean BCVA or mean CST at week 48. However, BCVA was stable in the prn-IVB group, while prn-IVT was associated with BCVA reduction from baseline and a higher risk of IOP elevation.

Recovery of Non-tuberculous Mycobacteria from Water is Influenced by Phenotypic Characteristics and Decontamination Methods.

Infections related to non-tuberculous mycobacteria (NTM) have recently increased worldwide. The transmission of these microorganisms from the environment has been suggested as the main source for human infections. To elucidate the epidemiological aspects and distribution of these pathogens, many studies have evaluated several decontamination methods and protocols to properly isolate NTM from environmental samples, mainly from water. However, no satisfactory strategy has been found for isolation of most of the NTM species harboring different phenotypic characteristics. Here, we evaluated the susceptibility of 23 NTM strains presenting variable growth rate and pigmentation patterns to eight different methods: oxalic acid (2.5% and 5%), cetylpyridinium chloride (CPC) (0.0025% and 0.005%), sodium hydroxide (NaOH) (2% and 4%), and sodium dodecyl sulfate (SDS) plus NaOH (SDS 1.5%-NaOH 0.5% and SDS 3%-NaOH 1%). It was found that the viability of NTM exposed to different decontamination methods varies according to their phenotypic characteristics and two methods (SDS 1.5% plus NaOH 0.5% and CPC 0.0025%) were necessary for effective isolation of all of the species tested. These findings supply important insights for future studies on the environmental occurrence of mycobacteria and improving the sensibility of traditional strategies.

Alternatives for the enforcement of the right to health in Brazil.

In this article, the right to health is discussed as a social right and an essential requisite in the construction and guarantee of human rights, more precisely human dignity, considering this right as a complex but effective process in the transformation of the social reality. In the first place, the activities of the public power and its difficulties to guarantee universal access to health are highlighted. This scenario ends up inhibiting the practice of the right to health and prevents users from enjoying and using it. In that sense, this article challenges and explores some alternatives to solidify and put in practice the right to health in Brazil. Departing from the analysis of the Unified Health System (SUS) and social participation in Brazil, this article discusses the judicialization of health in the country, highlighting the difficulties the State faces to equitably offer universal healthcare to society. This context offers an opportunity for reflection and a paradigm change, from the "judicialization of health" to the "judicialization of health policies." Finally, the public health policies adopted by other countries are emphasized, in the attempt to construct the empowerment of human beings in the practice of their rights, particularly social participation and the discussion about the States' responsibility to put their citizens' right to health in practice. In conclusion, the political and collective construction of the right to health needs to be encouraged, distinguishing the legitimate interests of the different interlocutors involved.

Neuroprotective effects of intravitreal triamcinolone acetonide and dexamethasone implant in rabbit retinas after pars plana vitrectomy and silicone oil injection.

PURPOSE: To investigate potential retinal neuroprotective effects of intravitreal triamcinolone acetonide and dexamethasone implant in rabbits after pars plana vitrectomy and intravitreal silicone oil injection. METHODS: The right eyes of 84 rabbits, divided into 3 groups of 28 rabbits each, underwent standard 3-port pars plana vitrectomy with silicone oil (SO group), silicone oil and intravitreal dexamethasone implant (SO/DEX group), or silicone oil and triamcinolone acetonide (SO/TA group). The retina from the left eye of each rabbit served as a control. The animals were killed at 4 weeks after surgery. Qualitative and quantitative histopathologic analyses were performed 4 weeks after surgery, and investigation for apoptosis was performed using the Tunel assay. RESULTS: Intravitreal triamcinolone acetonide and dexamethasone implant were associated with increased retinal neuronal survival, primarily in the outer nuclear layer, inner nuclear layer, and ganglion cell layer. In the SO group, the cell density in eyes that underwent PPV/SO was 31% lower in the outer nuclear layer, 33% lower in the inner nuclear layer, and 45% lower in the ganglion cell layer compared to control eyes (p < 0.05 for all PPV/SO versus control comparisons). Compared to eyes that underwent PPV/SO, the cell density in eyes treated with triamcinolone was 27% higher in the outer nuclear layer, 66% higher in the inner nuclear layer, and 100% higher in the ganglion cell layer (p < 0.05 for all triamcinolone versus PPV/SO comparisons). Compared to eyes that underwent PPV/SO, the cell density in eyes treated with dexamethasone was 46% higher in the outer nuclear layer, 62% higher in the inner nuclear layer, and 77% higher in the ganglion cell layer (p < 0.05 for all dexamethasone versus PPV/SO comparisons). Analyses using the Tunnel assay demonstrated apoptotic bodies in all eyes in the SO group, compared with none of the eyes in the SO/TA and SO/DEX groups. The presence of cell nuclei stained with 49,6-diamidino-2-phenylindole (DAPI) was demonstrated in all groups. CONCLUSION: In this experimental model of neuroprotection, increased retinal neuronal survival was seen in the steroid-treated groups compared with the controls.

Coastline changes and sedimentation related with the opening of an artificial channel: the Valo Grande Delta, SE Brazil.

The role played by human activity in coastline changes indicates a general tendency of retreating coasts, especially deltaic environments, as a result of the recent trend of sea level rise as well as the blockage of the transfer of sediments towards the coast, especially due to the construction of dams. This is particularly important in deltaic environments which have been suffering a dramatic loss of area in the last decades. In contrast, in this paper, we report the origin and evolution of an anthropogenic delta, the Valo Grande delta, on the south-eastern Brazilian coast, whose origin is related to the opening of an artificial channel and the diversion of the main flow of the Ribeira de Iguape River. The methodology included the analysis of coastline changes, bathymetry and coring, which were used to determine the sedimentation rates and grain-size changes over time. The results allowed us to recognize the different facies of the anthropogenic delta and establish its lateral and vertical depositional trends. Despite not being very frequent, anthropogenic deltas represent a favorable environment for the record of natural and anthropogenic changes in historical times and, thus, deserve more attention from researchers of different subjects.

Etiological agents of fungal endophthalmitis: diagnosis and management.

Endophthalmitis caused by fungi is commonly diagnosed around the world in apparently healthy and immunocompromised individuals. An accurate clinical diagnosis for endophthalmitis confirmed by laboratory techniques is essential for early treatment with antifungal drugs, such as amphotericin B, imidazoles, and other antifungals. Here, we review endophthalmitis caused by fungi according to its classification into endogenous fungal endophthalmitis (EFE) and exogenous fungal endophthalmitis (EXFE). EFE is caused by endogenously acquired fungi, whereas the traumatic implantation of opportunistic fungal pathogens is the main feature of EXFE. We highlight the most important etiologies causing endophthalmitis and the steps required for a rapid diagnosis and management.

Spatial-temporal variations of metals and arsenic in sediments from the Doce River after the Fundão Dam rupture and their bioaccumulation in Corbicula fluminea.

The rupture of the Fundão dam in Brazil released tons of mining tailings into the Doce River Basin (DRB). This investigation aimed to determine the bioaccumulation of metals in soft tissues of the bivalve Corbicula fluminea exposed to sediments collected in the DRB in four periods (just after, 1, 3, and 3.5 years after the dam rupture). In the exposure bioassays, the concentrations of Al, As, Cd, Cr, Cu, Fe, Mn, Ni, Pb, and Zn in sediments and bivalve soft tissues were quantified. The concentration of some elements (As, Cd, Mn, and Al) in sediments exceeded the federal limits or regional backgrounds at some sampling sites, but their concentrations tended to decrease over time. However, higher concentrations of many elements were detected in the winter of 2019. Several elements were detected in C. fluminea soft tissues, but the bioaccumulation factors were generally low or not related to those elements associated with the ore tailings, evidencing that the bioavailability of metals to bivalves, in laboratory conditions, was limited. Integr Environ Assess Manag 2024;20:87-98. © 2023 SETAC.

Managing Metastatic Renal Cell Carcinoma after Progression on Immunotherapy.

Treatment of metastatic renal cell carcinoma (mRCC) after first-line immune checkpoint inhibitors (ICIs) lacks standardization, with limited evidence from small trials and retrospective data. Vascular endothelial growth factor receptor (VEGFR) inhibition through tyrosine kinase inhibitors (TKIs) is the most widely adopted second-line treatment. Encouraging results have been seen with VEGFR-TKIs in the second-line after exposure to an ICI-based combination, achieving a response rate of 30%, and 75% of patients achieving disease control. Rechallenge with ICI alone seems safe but has limited clinical benefit. Promising regimens with combination therapies and novel drugs are being evaluated in phase 3 trials.

Correlation between the shear modulus measured by elastography (SSI) and tangent modulus from tensile tests of in vitro fresh-frozen human tendons.

Assessing the mechanical properties of tendons in vivo allows for quantifying the degree of pathology and tracking functional improvements. The Supersonic Shearwave Imaging (SSI) technique is a state-of-the-art method for analyzing musculoskeletal tissues in vivo. This technique estimates tissue stiffness as the shear elastic modulus µ [kPa]. However, only a few studies have validated the accuracy of SSI-estimated shear modulus against the gold standard for in vitro material testing, the tensile test. This study compared the SSI-measured shear elastic modulus (µ) with the tangent modulus (Etan) obtained from mechanical tensile tests for human Achilles (AT) and patellar tendons (PT). The sample comprised eleven fresh-frozen human Achilles tendons and five fresh-frozen human patellar tendons from cadavers that were not degraded by formalin or ionizing radiation. The tendons were tested in a tensile machine, and elastography videos were collected and segmented every 5% of the total experiment time. The absolute µ values estimated from both instruments presented an up to 20-fold difference. However, a strong significant positive correlation was found between µ and Etan for both tendons (range AT: R = 0.9765-0.9972 and PT: R = 0.8719-0.9782). The two resulting curves (µ and Etan) as a function of strain (ε) were normalized by their maxima for visually comparing stiffness × strain profiles. In conclusion, despite the inaccurate absolute values, SSI has been shown to measure relative changes in human Achilles and patellar tendon stiffness. This study endorses future clinical use of SSI to provide in vivo estimations of human tendons' mechanical properties.

Polycyclic aromatic hydrocarbons in a Natural Heritage Estuary influenced by anthropogenic activities in the South Atlantic: Integrating multiple source apportionment approaches.

Polycyclic aromatic hydrocarbons (PAHs) were analysed in the sediments of one of the most well-preserved estuaries in South Brazil, the Paranaguá Estuarine System (PES), using several source apportionment tools. The ∑PAH ranged from < DL to 125.6 ng g-1 dw (dry weight) (average 29.9 ± 26.1 ng g-1 dw), and the lowest levels detected were similar to those found in other protected areas of the world. In general, the PAH concentrations indicated excellent environmental quality for the entire estuary. Principal component analysis indicated that fine sediments and total organic carbon were the main factors controlling PAH concentrations in the PES. Multiple PAH sources were identified in the study area; biomass burning and fossil fuel combustion predominated but considerable amounts of petrogenic residues were also observed. We identified evidence of a contribution from an adjacent watershed resulting from the construction of interconnections between large rivers and from years of intense deforestation in the local Atlantic Forest.

Unusual natural polycyclic aromatic hydrocarbons in sediment cores of an Amazon estuary.

Polycyclic aromatic hydrocarbons (PAHs) most likely derived from natural sources were observed in two sediment cores covering the last 100 years in an Amazon estuarine region. A considerable change in the PAHs main source was observed in the 1960s. Before the 1960s, the sources of PAHs seem to be related to biogenic and/or early-diagenetic processes. Concentrations of perylene were higher before the 1960s and suggest that its primary source to the sediments in the Amazon region is linked to a short-term diagenetic transformation of their biogenic precursors. The natural formation of alkylated PAHs in sediments was linked to the methylation of the parental aromatic hydrocarbons due to sediment maturation processes and the dehydrogenation of sterols in the sediments. The relatively rapid reaction occurring in recent sediments of the Amazon region suggests the importance of the microbial community in the transformation of biogenic precursors to alkylated-PAHs in the sediments.

Suppressed accumulation of cerebral amyloid {beta} peptides in aged transgenic Alzheimer's disease mice by transplantation with wild-type or prostaglandin E2 receptor subtype 2-null bone marrow.

A complex therapeutic challenge for Alzheimer's disease (AD) is minimizing deleterious aspects of microglial activation while maximizing beneficial actions, including phagocytosis/clearance of amyloid beta (Abeta) peptides. One potential target is selective suppression of microglial prostaglandin E(2) receptor subtype 2 (EP2) function, which influences microglial phagocytosis and elaboration of neurotoxic cytokines. To test this hypothesis, we transplanted bone marrow cells derived from wild-type mice or mice homozygous deficient for EP2 (EP2(-/-)) into lethally irradiated 5-month-old wild-type or APPswe-PS1DeltaE9 double transgenic AD mouse model recipients. We found that cerebral engraftment by bone marrow transplant (BMT)-derived wild-type or EP2(-/-) microglia was more efficient in APPswe-PS1DeltaE9 than in wild-type mice, and APPswe-PS1DeltaE9 mice that received EP2(-/-) BMT had increased cortical microglia compared with APPswe-PS1DeltaE9 mice that received wild-type BMT. We found that myeloablative irradiation followed by bone marrow transplant-derived microglia engraftment, rather than cranial irradiation or BMT alone, was responsible for the approximate one-third reduction in both Abeta plaques and potentially more neurotoxic soluble Abeta species. An additional 25% reduction in cerebral cortical Abeta burden was achieved in mice that received EP2(-/-) BMT compared with mice that received wild-type BMT. Our results provide a foundation for an adult stem cell-based therapy to suppress soluble Abeta peptide and plaque accumulation in the cerebrum of patients with AD.

Use of nonhuman primate models to investigate mechanisms of infection-associated preterm birth.

Preterm birth is the most important direct cause of neonatal mortality and remains a major challenge for obstetrics and global health. Intrauterine infection causes approximately 50% of early preterm births. Animal models using pregnant mice, rabbits or sheep demonstrate the key link between infection and premature birth, but differ in the mechanisms of parturition and placental structure from humans. The nonhuman primate (NHP) is a powerful model which emulates many features of human placentation and parturition. The contributions of the NHP model to preterm birth research are reviewed, emphasising the role of infections and the potential development of preventative and therapeutic strategies.

Early determinants of death due to multiple organ failure after noncardiac surgery in high-risk patients.

BACKGROUND: Prediction of perioperative cardiac complications is important in the medical management of patients undergoing noncardiac surgery. However, these patients frequently die as a consequence of primary or secondary multiple organ failure (MOF), often as a result of sepsis. We investigated the early perioperative risk factors for in-hospital death due to MOF in surgical patients. METHODS: This was a prospective, multicenter, observational cohort study performed in 21 Brazilian intensive care units (ICUs). Adult patients undergoing noncardiac surgery who were admitted to the ICU within 24 hours after operation were evaluated. MOF was characterized by the presence of at least 2 organ failures. To determine the relative risk (RR) of in-hospital death due to MOF, we performed a logistic regression multivariate analysis. RESULTS: A total of 587 patients were included (mean age, 62.4 ± 17 years). ICU and hospital mortality rates were 15% and 20.6%, respectively. The main cause of death was MOF (53%). Peritonitis (RR 4.17, 95% confidence interval [CI] 1.38-12.6), diabetes (RR 3.63, 95% CI 1.17-11.2), unplanned surgery (RR 3.62, 95% CI 1.18-11.0), age (RR 1.04, 95% CI 1 0.01-1.08), and elevated serum lactate concentrations (RR 1.52, 95% CI 1.14-2.02), a high central venous pressure (RR 1.12, 95% CI 1.04-1.22), a fast heart rate (RR 3.63, 95% CI 1.17-11.2) and pH (RR 0.04, 95% CI 0.0005-0.38) on the day of admission were independent predictors of death due to MOF. CONCLUSIONS: MOF is the main cause of death after surgery in high-risk patients. Awareness of the risk factors for death due to MOF may be important in risk stratification and can suggest routes for therapy.

Intravitreal injection of autologous bone marrow-derived mononuclear cells for hereditary retinal dystrophy: a phase I trial.

PURPOSE: To evaluate the short-term (10 months) safety of a single intravitreal injection of autologous bone marrow-derived mononuclear cells in patients with retinitis pigmentosa or cone-rod dystrophy. METHODS: A prospective, Phase I, nonrandomized, open-label study including 3 patients with retinitis pigmentosa and 2 patients with cone-rod dystrophy and an Early Treatment Diabetic Retinopathy Study best-corrected visual acuity of 20/200 or worse. Evaluations including best-corrected visual acuity, full-field electroretinography, kinetic visual field (Goldman), fluorescein and indocyanine green angiography, and optical coherence tomography were performed at baseline and 1, 7, 13, 18, 22, and 40 weeks after intravitreal injection of 10 × 10(6) autologous bone marrow-derived mononuclear cells (0.1 mL) into 1 study eye of each patient. RESULTS: No adverse event associated with the injection was observed. A 1-line improvement in best-corrected visual acuity was measured in 4 patients 1 week after injection and was maintained throughout follow-up. Three patients showed undetectable electroretinography responses at all study visits, while 1 patient demonstrated residual responses for dark-adapted standard flash stimulus (a wave amplitude approximately 35 µV), which remained recordable throughout follow-up, and 1 patient showed a small response (a wave amplitude approximately 20 µV) recordable only at Weeks 7, 13, 22, and 40. Visual fields showed no reduction (with a Goldman Standard V5e stimulus) for any patient at any visit. No other changes were observed on optical coherence tomography or fluorescein and indocyanine green angiograms. CONCLUSION: Intravitreal injection of autologous bone marrow-derived mononuclear cells in eyes with advanced retinitis pigmentosa or cone-rod dystrophy was associated with no detectable structural or functional toxicity over a period of 10 months. Further studies are required to investigate the role, if any, of autologous bone marrow-derived mononuclear cell therapy in the management of retinal dystrophies.

Radiocarbon geochronology of the sediments of the São Paulo Bight (southern Brazilian upper margin).

The aim of this work was to generate an inventory of the data on radiocarbon datings obtained from sediments of the São Paulo Bight (southern Brazilian upper margin) and to analyze the data in terms of Late Quaternary sedimentary processes and sedimentation rates. A total of 238 radiocarbon datings from materials collected using differents ampling procedures was considered for this work. The sedimentation rates varied from less than 2 to 68 cm.kyr(-1). The highest sedimentation rate values were found in a low-energy (ría type) coastal system as well as in the upwelling zones of Santa Catarina and Cabo Frio. The lowest rates were found on the outer shelf and upper slopes. Our results confirm the strong dependency of the shelf currents, with an emphasis to the terrigenous input from the Río de La Plata outflow which is transported via the Brazilian Coastal Current, as well as of the coupled Brazil Current - Intermediate Western Boundary Current (BC-IWBC) dynamics on the sedimentary processes. At least three indicators of the paleo sea level were found at 12200 yr BP (conventional radiocarbon age) (103 meters below sea level - mbsl), 8300-8800 cal yr BP (13 mbsl) and 7700-8100 cal yr BP (6 mbsl).

The importance of adhesive area delimitation in a microshear bond strength experimental design.

PURPOSE: The purpose of this study was to assess the influence of adhesive area delimitation on the microshear bond strength of different adhesives to dentin. MATERIALS AND METHODS: Eighteen bovine incisors were sectioned and the exposed dentin surfaces were prepared with 600-grit SiC paper. These teeth were randomly divided into three groups, according to the adhesive to be applied: two-step etch-and-rinse Adper Single Bond 2 (3M ESPE), two-step self-etching Clearfil SE Bond (Kuraray), and one-step Clearfil S3 Bond (Kuraray). On each dentin surface, 4 samples were built up with the composite resin Z100 (3M ESPE); on 2 of these, a suggested area delimitation technique was employed. After 24 h of storage in water at 37°C, samples were subjected to the microshear bond strength test, and the failure modes were evaluated under optical and scanning electron microscopes. The obtained results were statistical analyzed using two-way ANOVA and Tukey's test. RESULTS: Groups without area delimitation presented significantly higher bond strength results (p < 0.05) and a higher incidence of cohesive failures. In these groups, fractures tended to occur beyond the limits of the actual adhesive area, while the area restriction technique succeeded in avoiding this phenomenon. The three adhesives performed similarly when area delimitation was employed (p > 0.05), but Clearfil S3 Bond showed significantly higher bond strength results when no area delimitation was taken into account (p < 0.05). CONCLUSION: The extension of the adhesive area beyond the limits of the composite cylinder may play an important role in the results of microshear bond strength tests, while the suggested area delimitation technique may lead to less questionable outcomes.

Use of fimH single-nucleotide polymorphisms for strain typing of clinical isolates of Escherichia coli for epidemiologic investigation.

Strain typing methods that compare electrophoresis banding patterns are commonly used but are difficult to standardize and poorly portable. Multilocus sequence typing (MLST) is a sequence-based alternative, but it is not practical for large-scale epidemiological studies. In the present study, the usefulness of fimH single-nucleotide polymorphisms (SNPs) for Escherichia coli typing was explored. fimH SNPs were determined for 345 E. coli clinical isolates (including 3 reference strains) and compared to PCR-based ECOR (E. coli reference collection) phylogrouping. The fimH gene could be amplified for 316 (92%) of the 345 isolates. fimH SNP analysis found 46 distinct terminal groups in the nucleotide sequence-based phylogenetic tree (fimH types). A subset of the E. coli isolates (162 clinical isolates and the 3 reference strains) were compared by fimH type, PCR phylogroup, and MLST. These isolates fell into 27 fimH types and 18 MLST clonal complexes (CCs) that contained 2 to 28 isolates per complex. The combination of PCR phylogroup and fimH type corresponded to a single CC for 113 (68%) isolates and 2 or 3 CCs for the other 52 (32%) isolates. We propose that the combination of PCR phylogrouping and fimH SNP analysis may be a useful method to type a large collection of clinical E. coli isolates for epidemiologic studies.