A hospital-based matched case-control study to identify risk factors for clinical infection with OXA-48-producing Klebsiella pneumoniae in rectal carriers.

Asymptomatic colonisation of the gastrointestinal tract by carbapenemase-producing Enterobacteriaceae is an important reservoir for transmission, which may precede infection. This retrospective observational case-control study was designed to identify risk factors for developing clinical infection with OXA-48-producing Klebsiella pneumoniae in rectal carriers during hospitalisation. Case patients (n = 76) had carbapenemase-producing K. pneumoniae (CPKP) infection and positive rectal culture for CPKP. Control patients (n = 174) were those with rectal colonisation with CPKP but without CPKP infection. Multivariate analysis identified the presence of a central venous catheter (OR 4·38; 95% CI 2·27-8·42; P = 0·008), the number of transfers between hospital units (OR 1·27; 95% CI (1·06-1·52); P < 0·001) and time at risk (OR 1·02 95% CI 1·01-1·03; P = 0·01) as independent risk factors for CPKP infection in rectal carriers. Awareness of these risk factors may help to identify patients at higher risk of developing CPKP infection.

Evaluation of rectus abdominis muscle strength and width of hernia defect in patients undergoing incisional hernia surgery.

BACKGROUND: The aim of this study was to analyze the strength status of the rectus abdominis muscle in patients with incisional hernia and the relationship between the width of the hernia defect and the strength of the rectus abdominis muscle. METHODS: This is a observational cohort study of patients with medial line incisional hernia (July-October 2022), classified as W2 according to the European Hernia Society (EHS). The data collected were demographic and clinical characteristics related to hernia, and measure of the rectus abdominis muscle strength using an isokinetic dynamometer and a strain gauge. We analyzed the relationship between hernia width and rectus abdominis muscle strength with correlation tests to adjustment by age, sex, BMI, and body composition. RESULTS: A total of 40 patients (64% female) with a mean age of 57.62 years (SD 11) were enrolled in the study. The mean BMI was 29.18 (SD 5.06), with a mean percentage of fat mass of 37.8% (SD 8.47) and a mean percentage of muscle mass of 60.33% (SD 6.43). The maximum width of the hernia defect was 6.59 cm (SD 1.54). In the male group, the mean bending force moment (ISOK_PT) was 94.01 Nw m (SD 34.58), bending force moment relative to body weight (ISOK_PT_Weight) was 103.32 Nw m (SD 37.48), and peak force (PK_90) was 184.71 N (SD 47.01). In the female group, these values were 58.11 Nw m (SD 29.41), 66.48 Nw m (SD 32.44), and 152.50 N (SD 48.49), respectively. Statistically significant differences were observed in the relationship between the data obtained with the isokinetic dynamometer and sex (p = 0.002), as well as between the data obtained with the isokinetic dynamometer and age (p = 0.006). Patients in the 90th percentile (P90) of rectus abdominis muscle strength also had smaller hernia defect widths (p = 0.048). CONCLUSIONS: In this study, age and sex were identified as the most statistically significant predictor variables for rectus abdominis muscle strength. The width of the hernia defect exhibited a trend towards statistical significance.

Sonication did not provide reliability to Maki technique for catheter related bloodstream infection diagnosis.

OBJECTIVE: The aim of our study was to analyze sonication and Maki techniques for diagnosis of catheter tip colonization and catheter-related bloodstream infection (CRBSI) on patients admitted to ICU. METHODS: Observational and prospective study in one Intensive Care Unit. Patients with some central venous catheter (CVC) at least for 7 days and catheter-related infection (CRI) suspicion (new episode of fever or sepsis) were included. We performed Maki technique followed by sonication of catheter tip. We compared area under the curve (AUC) of Maki, sonication, and techniques combination to diagnosis catheter tip colonization and CRBSI. RESULTS: We included 94 CVC from 87 CRI suspicion episodes. We found 14 cases of catheter tip colonization and 10 cases of CRBSI. Of the 14 catheter tip colonization cases, 7 (50.0%) were detected by Maki and sonication techniques, 6 (42.9%) were detected only by Maki technique, and 1 (7.1%) was detected only by sonication technique. Of the 10 CRBSI, 6 (60.0%) were detected by Maki and sonication techniques, 4 (40.0%) were detected only by Maki technique, and any only by sonication technique. We found higher AUC in Maki technique than in sonication technique to diagnosis of CRBSI (p=0.02) and to diagnosis of catheter tip colonization (p=0.03). No significant differences were found in AUC between Maki technique and combination techniques for diagnosis of catheter tip colonization (p=0.32) and of CRBSI (p=0.32). CONCLUSIONS: Sonication did not provide reliability to Maki technique for diagnosis of catheter tip colonization and CRBSI.

Electrorheological response and orientational bistability of a homogeneously aligned nematic capillary.

We consider a homogeneously aligned nematic liquid crystal confined in the region between two rotating coaxial cylinders. We study the nematic's director and velocity profiles induced by the imposed Couette flow and an applied radial electric field. We present calculations for the specific flow-aligning nematic liquid crystal 4(')-n-pentyl-4-cyanobiphenyl and numerically solve a hydrodynamic model assuming hard anchoring and nonslip boundary conditions. We calculate a phase diagram in the parameter space showing a region where there exist multiple equilibrium solutions for the nematic's configuration and a region where there exists only one stationary solution. We also study the rheology of the system by calculating the apparent viscosity and the first normal stress difference. We find that the competition between the Couette flow and the electric field gives rise to an interesting non-Newtonian response which switches its behavior from shear thickening to shear thinning by exceeding a critical field.

Electrorheological effect and directional non-Newtonian behavior in a nematic capillary subjected to a pressure gradient.

We consider a capillary consisting of two coaxial cylinders whose core is filled with a nematic liquid crystal (LC) subjected to the simultaneous action of both a pressure gradient applied parallel to the axis of the cylinders and a radial low frequency electric field. We find the configuration of the director of the nematic, initially with an escaped-like configuration, for the flow aligning LC 4'-n-pentyl-4-cyanobiphenyl (5CB) by assuming hard anchoring hybrid boundary conditions. Also, we obtain the velocity profile parametrized by the electric field and the pressure gradient for nonslip boundary conditions. Finally, we calculate exactly the effective viscosity, the first normal stress difference, and the dragging forces on the cylinders. The results show an important electrorheological effect and a directional non-Newtonian response with regions of flow thinning and thickening.

Threshold field for a nematic liquid crystal confined between two coaxial cylinders.

We consider a nematic liquid crystal constrained by two coaxial cylinders under the action of low-frequency axial or radial electric fields. Assuming an initially hybrid configuration, we find the equilibrium texture of the nematic subjected to weak anchoring boundary conditions on both cylindrical surfaces. We analyze the distinct textures of the nematic as a function of the strength of the interaction of the nematic with the sidewalls, the radii ratio of the cylinders, and the applied electric field. Also, for each radii ratio and strength of the nematic-surface interaction, we determine the critical field for which a complete alignment of the nematic liquid crystal occurs.

Dissemination and clinical implications of multidrug-resistant Klebsiella pneumoniae isolates producing OXA-48 in a Spanish hospital.

BACKGROUND: Healthcare-associated infections caused by Klebsiella pneumoniae isolates are increasing and few effective antibiotics are currently available to treat patients. AIM: To assess the epidemiology, molecular basis, clinical features, and outcomes in the acquisition and dissemination of OXA-48-producing K. pneumoniae (OXA48KP) in a tertiary Spanish hospital between October 2013 and December 2015. METHODS: Clinical, demographic, and microbiological data of patients with OXA48KP in clinical samples were collected from medical records. Carbapenemase genes were detected by polymerase chain reaction. Genetic relationships were determined by pulsed-field gel electrophoresis and multi-locus sequence typing. FINDINGS: In all, 116 episodes of OXA48KP in clinical samples were identified. The most frequent types of infection were urinary tract (N = 43, 42%), secondary bloodstream (N = 18, 17%), and surgical site infection (N = 17, 17%). More than one-quarter (28%) of infected patients died in hospital. Among infected patients (N = 90, 78%), infections were mainly classified as hospital-acquired (N = 70, 88%). A high number of OXA48KP isolates showed multidrug resistance, with highest susceptibility to colistin (86%), gentamicin (69%) and amikacin (59%). Most (87%) isolates were included in a main cluster. Seven (N = 8, 88%) isolates showed an identical allelic profile, associated with ST15. Only the isolate from cluster P8 was associated with ST29. The results confirm high dissemination of OXA48KP in our hospital due to the main clone ST15. OXA48KP infection was associated with a high mortality and was mainly hospital-acquired. CONCLUSION: This study highlights the importance of active surveillance programmes, especially those focusing on hospital readmissions in order to control the spread of carbapenemase-producing Enterobacteriaceae.

Saturation and stability of nonlinear photonic crystals.

We consider a one-dimensional photonic crystal made by an infinite set of nonlinear nematic films immersed in a linear dielectric medium. The thickness of each equidistant film is negligible and its refraction index depends continuously on the electric field intensity, giving rise to all the involved nonlinear terms, which joints from a starting linear index for negligible amplitudes to a final saturation index for extremely large field intensities. We show that the nonlinear exact solutions of this system form an intensity-dependent band structure which we calculate and analyze. Next, we ponder a finite version of this system; that is, we take a finite array of linear dielectric stacks of the same size separated by the same nonlinear extremely thin nematic slabs and find the reflection coefficients for this arrangement and obtain the dependence on the wave number and intensity of the incident wave. As a final step we analyze the stability of the analytical solutions of the nonlinear crystal by following the evolution of an additive amplitude to the analytical nonlinear solution we have found here. We discuss our results and state our conclusions.

[The acoustic distortion products application in noise pathology]. / Aplicación de los productos de distorsión acústica en la patología del ruido.

We study a total of 40 individuals exposed to noise in 3 forms of presentation: continuous (metal-workers), impact (hunters and policemen) and acute (bombs or fireworks). All them underwent a study with otoscopy, pure-tone audiometry, speech audiometry, tympanometry and recording of DP 2f1-f2 in the DPgram form. The results showed an early damage in DP (3 to 6 kHz). That are demonstrated by a decrease in recording in direct relation with increased audiometric threshold. Being obvious at 6 kHz among subjects exposed to continuous noise, though the smaller extent data are expressed in the records of 3 and 4 kHz, independently of noise form of exposure.

[Acute meningococcal disease. Study of auditive sequelae]. / Enfermedad meningocócica aguda. Investigación de secuelas auditivas.

We have examined the auditory function in 49 children that have survived an acute meningococcal disease (AMD). Functional auditory exploration consisted of: ABR; tonal liminal audiometry or behavioral audiometry (Peep-show method, Suzuki-Ogiba ROC) depending on the age and collaboration of the patient; and impedanciometrical techniques (tympanometry, ipsi and contra-lateral stapedial reflex). Three months later, altered tests were repeated in patients that had been evaluated at a time greater than 90 days after their first day of hospitalization (n = 18). All tests were repeated in those patients that had been evaluated before 90 days from the first day of hospitalization (n = 31). No transmission or neurosensory hearing impairments were detected as a result of AMD. We consider the absence of neurosensory hearing impairment, despite the presence of significant risk factors, an important finding. These results suggest that the risk of hearing impairment could be reduced to a minimum by the early establishment of antibiotic treatment.

Evaluación de la hipoacusia por ruido mediante otoemisiones acústicas y productos de distorsión / Noise-induced hearing loss valuation with otoacoustic emissions and distortion products

La aplicación de los registros de productos de distorsión acústica a la patología auditiva derivada de la exposición a ruido se hace especialmente interesante por su carácter de análisis frecuencia¡. Estudiamos un total de 34 sujetos expuestos a ruido en tres formas de presentación: continua (trabajadores de metalurgia), de impacto (cazadores y agentes de orden) y aguda (explosiones de artefactos). A todos les realizamos un estudio consistente en otoscopia, audiometría tonal, logoaudiometría, impedanciometría y registro de PD 2fl-f2 en forma de Pdgrama. Los resultados evidencian una afectación precoz en los PD de frecuencias 3-6 kRz de f2, que se manifiestan por disminución de incidencia de registro en relación con el aumento de¡ umbral audiométrico, más evidente en frecuencia 6kRz de f2 en los sujetos expuestos a ruido continuo, aunque los datos de menor amplitud se manifiestan en los registros de 3 y 4 kRz, independientemente de la forma de presentación del ruido. (AU)