Carriage of multidrug-resistant Gram-negative bacilli: duration and risk factors.

Identification of risk factors influencing the duration of carriage of multidrug-resistant Gram-negative bacilli (MDR-GNB) may be useful for infection control. The aim of this study is to estimate the impact of several factors collected for routine hospital surveillance on the duration of carriage of selected MDR-GNB. From January 2015 to July 2021, patients with at least two clinical/surveillance samples positive for MDR-GNB different from ESBL-producing E. coli or AmpC - exclusively producing Enterobacterales were assessed. Microorganisms, age, number of admissions, clinical or rectal sample, sex, and admission service were evaluated as risk factors. Multivariate analysis was performed by a Cox proportional hazard model. A total of 1981 episodes of colonization were included. Involved microorganisms were ESBL-Klebsiella pneumoniae (KP) in 1057 cases (53.4%), other ESBL-non-E. coli Enterobacterales in 91 (4.6%), OXA-48-KP in 263 (13.3%), KPC-KP in 90 (4.5%), VIM-KP in 29 (1.5%), carbapenemase-producing non-KP Enterobacterales (CP-non-KP) in 124 (6.3%), and MDR Pseudomonas aeruginosa (MDR-PAER) in 327 (16.5%). No differences in duration of colonization were observed among ESBL-KP (median colonization time 320 days), ESBL-non-E. coli Enterobacterales (226 days), OXA48-KP (305 days), and MDR-PAER (321 days). For each group, duration of colonization was significantly longer than that of KPC-KP (median colonization time 60 days), VIM-KP (138 days), and CP-non-KP (71 days). Male sex (HR = 0.88; 95% CI 0.78-0.99), detection in Hepatology-Gastroenterology (HR = 0.71; 95% CI 0.54-0.93), clinical sample (HR = 0.61; 95% CI 0.53-0.69), and > 2 admissions after first detection (HR = 0.47; 95% CI 0.42-0.52) were independent predictors of longer carriage, whereas VIM-KP (HR = 1.61; 95% CI 1.04-2.48), KPC-KP (HR = 1.85; 95% CI 1.49-2.3), and CP-non-KP (HR = 1.92; 95% CI 1.49-2.47) were associated with shorter colonization time. Duration of colonization was significantly longer for ESBL-KP, other ESBL-non-E. coli Enterobacterales, OXA-48-KP, and MDR-PAER. For these microorganisms, prolonging surveillance up to 2.5-3 years should be considered. Male sex, clinical sample, multiple readmissions, admission service, and type of microorganism are independent predictors of the duration of carriage.

Pathological profiles of systemic infections by Panton-Valentine leukocidin-positive, methicillin-resistant Staphylococcus aureus strains in a murine model.

AIMS: Staphylococcus aureus is one of the most common pathogens in hospital environment and community. Panton-Valentine leukocidin (PVL) production is clinically associated with skin abscesses, soft tissues infections, bacteraemia and sepsis. This study aimed to investigate the effects of the presence of genes lukF/S-PV coding for PVL, in histological and haematological features during systemic infection, using a Swiss mice experimental model. METHODS AND RESULTS: Experiments were performed using 25 mice distributed into five experimental groups, intravenously inoculated with 50 µl suspensions at density 1·0 × 107  CFU per ml of strains: methicillin-susceptible (MSSA) and pvl-negative strains isolated from nasal colonization; MSSA pvl-positive strains isolated from nasal colonization; methicillin-resistant (MRSA) and pvl-positive strains isolated from peripheral blood of a patient with severe pulmonary infection; and a MRSA pvl-positive strains isolated from a peripheral blood culture of a patient with bacteraemia. Haematological analysis was performed at 24, 48, 72 and 96 h post-infection. Morphoanatomy and histopathological analyses were performed at 96 h post-infection. For all S. aureus strains tested, the capability of intravenous dissemination and survival into mice tissues was demonstrated. Inflammatory processes at different levels were related to the presence of pvl genes, and included alterations in the format, size and colour of the organs. Staphylococcus aureus pvl-positive strains were detected in greater numbers in the organs of the infected animals. CONCLUSIONS: The pvl-positive strains isolated from blood cultures were capable to induce the greatest modifications in both haematological and histopathological profiles, and seemed to aggravate the systemic infections. SIGNIFICANCE AND IMPACT OF THE STUDY: These findings are valuable in characterizing infections caused by S. aureus in humans and murine.

Executive functions and language in children with different subtypes of specific language impairment. / Funciones ejecutivas y lenguaje en subtipos de niños con trastorno específico del lenguaje.

INTRODUCTION: The marked heterogeneity among children diagnosed with specific language impairment (SLI) highlights the importance of studying and describing cases based on the distinction between the expressive and receptive-expressive SLI subtypes. The main objective of this study was to examine neuropsychological, linguistic, and narrative behaviours in children with different SLI subtypes. METHOD: A comprehensive battery of language and neuropsychological tests was administered to a total of 58 children (29 with SLI and 29 normal controls) between 5.60 and 11.20 years old. RESULTS: Both SLI subtypes performed more poorly than the control group in language skills, narrative, and executive function. Furthermore, the expressive SLI group demonstrated substantial ungrammaticality, as well as problems with verbal fluency and both verbal and spatial working memory, while the receptive-expressive SLI subtype displayed poorer neuropsychological performance in general. CONCLUSIONS: Our findings showed that children with either SLI subtype displayed executive dysfunctions that were not limited to verbal tasks but rather extended to nonverbal measures. This could reflect a global cognitive difficulty which, along with declining linguistic and narrative skills, illustrates the complex profile of this impairment.

Experimental and theoretical rationalization of the growth mechanism of silicon quantum dots in non-stoichiometric SiN x : role of chlorine in plasma enhanced chemical vapour deposition.

Silicon quantum dots (Si-QDs) embedded in an insulator matrix are important from a technological and application point of view. Thus, being able to synthesize them in situ during the matrix growth process is technologically advantageous. The use of SiH2Cl2 as the silicon precursor in the plasma enhanced chemical vapour deposition (PECVD) process allows us to obtain Si-QDs without post-thermal annealing. Foremost in this work, is a theoretical rationalization of the mechanism responsible for Si-QD generation in a film including an analysis of the energy released by the extraction of HCl and the insertion of silylene species into the terminal surface bonds. From the results obtained using density functional theory (DFT), we propose an explanation of the mechanism responsible for the formation of Si-QDs in non-stoichiometric SiN x starting from chlorinated precursors in a PECVD system. Micrograph images obtained through transmission electron microscopy confirmed the presence of Si-QDs, even in nitrogen-rich (N-rich) samples. The film stoichiometry was controlled by varying the growth parameters, in particular the NH3/SiH2Cl2 ratio and hydrogen dilution. Experimental and theoretical results together show that using a PECVD system, along with chlorinated precursors it is possible to obtain Si-QDs at a low substrate temperature without annealing treatment. The optical property studies carried out in the present work highlight the prospects of these thin films for down shifting and as an antireflection coating in silicon solar cells.

Loss of genetic diversity in farmed populations of Colossoma macropomum estimated by microsatellites.

The genetic variability of four Colossoma macropomum broodstocks, three from fish farms in different regions and one from the natural environment in Brazil, was analyzed using microsatellite markers. The wild progeny (n = 30) were caught in the Solimões-Amazonas River, at the varzea lakes; this location is used to mature the fish from larvae to juveniles. The three fish farms were selected according to the age of their lineages and broodstock availability: DNOCS (n = 21) is located in the Ceará State, representing the oldest lineage of cultivated tambaqui in Brazil; Balbina (n = 30) is located in the Amazonas State, representing the youngest stocks of tambaqui farmed in Brazil (approximately 15 years); and UFRPE (n = 30) is located in the Pernambuco State and is considered to be a mixed stock formed from the DNOCS and Balbina lineages. The analysis of 13 microsatellite loci indicated the occurrence of a variability reduction in the farmed populations; the UFRPE stock was the population with the highest diversity level. Low values of molecular coancestry were found in these populations. Additionally, significant differences in the RST values among the populations were detected, as was the occurrence of genetic structure. The genetic loss found in these populations may have been influenced by the founder effect. Because no breeding programs were during the entire production period and no pedigree records were kept for these broodstocks, we suggest that a wild population might be used as an important genetic resource to increase the genetic diversity of renewal stock lineages.

Influence of kaolin and red clay on ceramic specimen properties when galvanic sludge is incorporated to encapsulate heavy metals.

This study presented the influence of two types of clay: kaolin (Kao) and red clay (RC) on the chemical and physical properties of ceramic specimens when galvanic sludge (GS) is incorporated to encapsulate heavy metals. Samples were obtained of GS from the industrial district of Manaus - Amazonas State, Brazil, and kaolin (Kao), and red clay (RC) from the Central Amazon. A fourth sample was prepared by mixing GS, Kao, and RC in the ratio 1:1:8 (GS + Kao + RC). This mixture was ground, and ceramic specimens were prepared, and heat treated at 950 °C and 1200 °C for three hours for phase detection, compressive strength, leaching of Fe, Ni and Cr metals and life cycle assessment. Galvanic sludge, Kao, and RC were also, and heat treated to at 950 °C and 1200 °C for three hours, obtaining GS950, GS1200, Kao950, Kao1200, RC950, and RC1200. The samples were submitted to XRF, XRD, Rietveld refinement, Mössbauer spectroscopy, TG/DTG/DSC, and SEM. The results show that the formation of nickel oxide and a spinel solid solution of the type Fe3+{Fe1-y3+,Fe1-x2+,Nix2+,Cry3+}O4 (in which [] = tetrahedral site, {} octahedral site) occurs in GS1200, which is caused by sulfate decomposition to SO2. At 1200 °C, heavy metals are encapsulated, forming other phases such as nickel silicate and hematite. Life cycle assessment was used to verify the sustainability and value of GS in clay for making bricks, and it indicated that the production of ceramics is feasible, reduces the use of clays, and is sustainable.

A short review on the features of the non-obese diabetic Goto-Kakizaki rat intestine.

The Goto-Kakizaki (GK) rat is a non-obese experimental model of type 2 diabetes mellitus (T2DM) that allows researchers to monitor diabetes-induced changes without jeopardizing the effects of obesity. This rat strain exhibits notable gastrointestinal features associated with T2DM, such as marked alterations in intestinal morphology, reduced intestinal motility, slow transit, and modified microbiota compared to Wistar rats. The primary treatments for diabetic patients include administration of hypoglycemic agents and insulin, and lifestyle changes. Emerging procedures, including alternative therapies, metabolic surgeries, and modulation of the intestinal microbiota composition, have been shown to improve the diabetic state of GK rats. This review describes the morpho-physiological diabetic-associated features of the gastrointestinal tract (GIT) of GK rats. We also describe promising strategies, e.g., metabolic surgery and modulation of gut microbiota composition, used to target the GIT of this animal model to improve the diabetic state.

Decreased mortality among patients with catheter-related bloodstream infections at Catalan hospitals (2010-2019).

BACKGROUND: The incidence of catheter-related bloodstream infections (CRBSIs) has fallen over the last decade, especially in intensive care units (ICUs). AIM: To assess the existence of concomitant trends in outcomes and to analyse the current risk factors for mortality. METHODS: A multicentre retrospective cohort study was conducted at 24 Catalan hospitals participating in the Surveillance of healthcare-associated infections in Catalonia (VINCat). All hospital-acquired CRBSI episodes diagnosed from January 2010 to December 2019 were included. A common protocol including epidemiological, clinical, and microbiological data was prospectively completed. Mortality at 30 days after bacteraemia onset was analysed using the Cox regression model. FINDINGS: Over the study period, 4795 episodes of CRBSI were diagnosed. Among them, 75% were acquired in conventional wards and central venous catheters were the most frequently involved (61%). The 30-day mortality rate was 13.8%, presenting a significant downward trend over the study period: from 17.9% in 2010 to 10.6% in 2019 (hazard ratio (HR): 0.95; 95% confidence interval (CI): 0.92-0.98). The multivariate analysis identified age (HR: 1.03; 95% CI: 1.02-1.04), femoral catheter (1.78; 1.33-2.38), medical ward acquisition (2.07; 1.62-2.65), ICU acquisition (3.45; 2.7-4.41), S. aureus (1.59; 1.27-1.99) and Candida sp. (2.19; 1.64-2.94) as risk factors for mortality, whereas the mortality rate associated with episodes originating in peripheral catheters was significantly lower (0.69; 0.54-0.88). CONCLUSION: Mortality associated with CRBSI has fallen in recent years but remains high. Intervention programmes should focus especially on ICUs and medical wards, where incidence and mortality rates are highest.

[Carbapenemases produced in Klebsiella spp., and Pseudomonas aeruginosa in six hospitals in Bogotá - Colombia]. / Tipos de carbapenemasas expresadas en Klebsiella spp., y Pseudomonas aeruginosa resistente a carbapenémicos en seis hospitales de alta complejidad de la Ciudad de Bogotá - Colombia.

BACKGROUND: In the last decades, the prevalence of infections by carbapenem resistant gram-negative bacilli has been increased. OBJECTIVE: To determine types and frequency of the different carbapenemases in Klebsiella spp. and Pseudomonas aeruginosa, in six hospitals in Bogotá-Colombia. METHODS: Descriptive and observational study, in six hospitals in the city of Bogotá, in the period ftom January 2017 to August 2018. PCR were performed for KPC, GES, VIM, NDM, IMP and OXA-48 genes, in carbapenem resistant Klebsiella spp. and P aeruginosa. RESULTS: 52 P aeruginosa isolates amplified a carbapenemase gene, of which 39 (75%) were positive for KPC, 11 (21%) for VIM and two co-productions of KPC and VIM. Regarding Klebsiella spp. 165 strains amplified at least one carbapenemase gene, 98% expressed KPC and four isolates had co-productions of metallo-P-lactamases and KPC. DISCUSSION: This study provides valuable information, such as the increased production of KPC in P. aeruginosa información valiosa, como el incremento de producción de KPC en P. aeruginosa and the co-production of KPC plus metallobetalactamases, which has an implication both in treatment selection, isolation precautions and patient prognosisy.

Modification of the nonlinear optical absorption and optical Kerr response exhibited by nc-Si embedded in a silicon-nitride film.

We studied the absorptive and refractive nonlinearities at 532 nm and 26 ps pulses for silicon-nitride films containing silicon nanoclusters (nc-Si) prepared by remote plasma-enhanced chemical vapor deposition (RPECVD). Using a self-diffraction technique, we measured for the as-grown sample beta=7.7x10(-9)m/W, n(2)=1.8x10(-16)m(2)/W, and /chi(3)1111/ = 4.6x10(-10)esu; meanwhile, when the sample was exposed to an annealing process at 1000 degrees C during one hour in a nitrogen atmosphere, we obtained beta=-5x10(-10)m/W, n2=9x10(-17)m(2)/W, and /chi(3)1111/=1.1x10(-10)esu. A pure electronic nonlinear refraction was identified and a large threshold ablation of 41 J/cm(-2) was found for our films. By fitting nonlinear optical transmittance measurements, we were able to estimate that the annealed sample exhibits a response time close to 1 fs. We report an enhancement in the photoluminescence (PL) signal after the annealing process, as well as a red-shift due to an increment in size of the nc-Si during the thermal process.

Polymorphous silicon thin films obtained by plasma-enhanced chemical vapor deposition using dichlorosilane as silicon precursor.

Polymorphous silicon thin films (pm-Si) have been deposited from mixtures of dichlorosilane and hydrogen, using argon as the diluting gas by plasma-enhanced chemical vapor deposition. The deposition conditions were chosen to simultaneously obtain both Si nanocrystallites and an amorphous silicon matrix in the as-grown samples. High resolution transmission electron microscopy studies show the crystallinity of Si domains whose dimensions are in the interval of 2-14 nm. The surface passivation state of the silicon nanocrystals was inferred from Fourier transform infrared spectroscopy analysis. Two optical absorption edges, corresponding to the amorphous matrix and the Si nanocrystals, were observed for all the pm-Si thin films. Intense visible photoluminescence was observed for the as-grown samples. The possibility of using these thin films for the down-conversion effect in silicon solar cells is discussed.

Photoluminescence of as-grown silicon nanocrystals embedded in silicon nitride: influence of atomic hydrogen abundance.

Silicon nanocrystals embedded in silicon nitride films were grown by direct plasma enhanced chemical vapor deposition at 300 degrees C, using mixtures of SiH2Cl2/NH3/H2/Ar. The films composition and chemical stability was tested by Fourier Transform Infrared Spectroscopy and Rutherford Backscattering Spectroscopy. The influence of hydrogen abundance during the deposition process on the photoluminescence of as-grown samples was studied as a function of the radiofrequency power and hydrogen dilution flow rate. In situ Optical Emission Spectroscopy allowed the diagnostic of the species in the plasma region and their general trends as a function of the radiofrequency power. The changes in the hydrogen content and silicon incorporation to the film as a function of the radiofrequency power were discussed in terms of silicon nanocrystals formation and growth in the silicon nitride matrix. The photoluminescence emission from the as-grown samples was found to red-shift with increasing hydrogen abundance. This observation is consistent with the increase in silicon content associated to nc-Si of larger size. On the other hand, the photoluminescence intensity was observed to decrease for very high radiofrequency powers and hydrogen dilutions. High Resolution Transmission Electron Microscopy confirmed the presence of silicon nanocrystals embedded in the amorphous silicon nitride matrix and allowed the correlation between the nanocrystals size and the photoluminescence emission energy using the quantum confinement model.

Optical and electrical properties of MoO2 and MoO3 thin films prepared from the chemically driven isothermal close space vapor transport technique.

Chemically-driven isothermal close space vapour transport was used to prepare pure MoO2 thin films which were eventually converted to MoO3 by annealing in air. According to temperature-dependent Raman measurements, the MoO2/MoO3 phase transformation was found to occur in the 225 °C-350 °C range while no other phases were detected during the transition. A clear change in composition as well as noticeable modifications of the band gap and the absorption coefficient confirmed the conversion from MoO2 to MoO3. An extensive characterization of these two pure phases was carried out. In particular, a procedure was developed to determine the dispersion relation of the refractive index of MoO2 from the shift of the interference fringes of the used SiO2/Si substrate. The obtained data of the refractive index was corrected taking into account the porosity of the samples calculated from elastic backscattering spectrometry. The Debye temperature and the residual resistivity were extracted from the electrical resistivity temperature dependence using the Bloch-Grüneisen equation. MoO3 converted samples presented a very high resistivity and a typical semiconducting behavior. They also showed intense and broad luminescence spectra composed by several contributions whose temperature behavior was examined. Furthermore, surface photovoltage spectra were taken and their relation with the photoluminescence is discussed.

Identification and mapping of real acupoints in the anatomical topography of Boa constrictor.

Acupuncture is a therapy of the traditional Chinese medicine technique, which over the years has been widespread in the West. Defined as a needle-point treatment technique (acupoints), exactly preconfigured in the body to produce a specific physiological reaction to restore the balance between the function of conflicting states and homeostasis, alternating states of energy and thus maintain the ideal organ and body organization. Thus, the objective of this study was to map and describe the main points of acupuncture in the species Boa constrictor , and their indications to promote the balance of this species. The unprecedented result of the mapping was the discovery of specific acupoints with individual location indications without distribution in specific meridians and dispersedly distributed in the body.

Pentastomid, Raillietiella mottae Almeida, Freire and Lopes, 2008, infecting lizards in an area of caatinga, northeast, Brazil.

Pentastomids can infect the respiratory tract of lizards, causing their death and as a result influencing the population size of hosts. Despite this, studies on rates of pulmonary infection of Brazilian lizards, including those living in Caatinga ecosystems of northeastern Brazil are scarce. Active collections of lizards were performed from October to December 2004 in an area of Caatinga of the Estação Experimental de São João do Cariri -- EESJC (07 masculine 25' S and 36 masculine 30' W), located in the state of Paraíba, Northeast of Brazil. Forty-five lizards inhabiting granite outcrops in an area of Caatinga were captured, belonging to the following species: Tropidurus hispidus (Spix, 1825) (18 individuals), T. semitaeniatus (Spix, 1825) (15 individuals), Phyllopezus periosus Rodrigues, 1986 (6 individuals), and P. pollicaris (Spix, 1825) (6 individuals). Laboratory examination revealed that all species had some degree of pulmonary infection caused by Raillietiella mottae. The highest rates of prevalence (66.7%) and mean intensity of infection (5.25 +/- 2.01, range of 2-11) were observed in P. periosus. The results obtained in this study show that lizards of the Brazilian semi-arid region are infected by a generalist species of pentastomid. The most likely cause for such pattern is the similarity in lizards' diets (ants and termites). It is particularly noteworthy that T. semitaeniatus, P. periosus, and P. pollicaris represent new host records for R. mottae.

[Psychopathology associated with idiopathic nephrotic syndrome in the pediatric age group]. / Psicopatología del síndrome nefrótico idiopático en la edad pediátrica.

AIM: To analyze the influence of several variables in the genesis of psychological morbidity in children with idiopathic nephrotic syndrome (INS) as compared with healthy controls. METHODS: The Strengths and Difficulties Questionnaire (SDQ) was administered to children with INS (n = 23) and a control group of healthy children (n = 38). The SDQ is a well-known screening instrument for psychological/psychiatric morbidity in childhood. The questionnaire consists of five scales that evaluate emotional symptoms, behavioral problems, hyperactivity, peer problems and prosocial behavior. The total score is calculated by adding all the subscales except the prosocial behavior scale. In children with INS, type of treatment, sex, steroid dose, disease stage, disease duration, and prognosis (number of relapses/disease stage) were also noted. RESULTS: Statistically significant differences were found in two of the scales (emotional symptoms and peer problems), as well as in the total score in children with INS as compared with the control group (p < 0.05). A positive correlation was found between disease duration and total score in the INS group. CONCLUSIONS: Emotional and behavioral problems were more frequent in children with INS. The only variable related to the severity of the symptoms studied in these children was disease duration.

[FDG-PET: a new diagnostic approach in hip prosthetic replacement]. / La 18FDG-PET: una nueva aproximación diagnóstica en la infección protésica de cadera.

Infection following hip arthroplasties can present a diagnostic challenge. No test is 100 % sensitive and 100 % specific; this prospective study was undertaken to evaluate the utility of FDG-PET imaging for diagnosing infected joint replacements. 24 hip joint replacements were studied prospectively and we have complete diagnoses with clinical signs and symptoms, laboratory test, radiography, joint aspiration, radionuclide imaging including FDG-PET, and histopathologic examination. 11 of 24 prostheses were infected. The sensitivity and specificity of PET for detecting infection associated with prostheses were 64,3 % and 64,7 % respectively, in our hands. FDG imaging is not useful in patients with suspected prosthetic infection like a screening test.