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AIMS: The purpose of this study was to investigate the effects of compaction and air infiltration on the bacterial community structure during the fermentation process and the aerobic exposure phase of grass silage. METHODS AND RESULTS: Perennial ryegrass was ensiled at laboratory scale in a high-density (HD) and low-density (LD) compaction variant. Silages were exposed to air, and degradation was monitored by analysing temperature changes within the silage. Fermentation dynamics were examined using chemical analysis and terminal restriction fragment length polymorphism (TRFLP) analysis of the 16S rRNA gene supported by cloning and sequencing of representative samples. Dominant Lactobacillus species in HD silages remained largely unchanged during aerobic exposure. LD silages revealed fundamental changes in the bacterial community structure when exposed to air. After 4 days aerobic storage, only 23% of the primary silage community remained and mainly opportunistic Bacillus species proliferated. CONCLUSION: The ensiling of ryegrass is a very dynamic microbial process. Aerobic spoilage was limited to the LD silages, marked by a complete change towards a Bacillus-dominated community. SIGNIFICANCE AND IMPACT OF THE STUDY: The TRFLP analysis supported by the identification of terminal restriction fragments, revealed novel insights into the dynamics of the bacterial community during ensiling, and at aerobic spoilage conditions.
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Bacterias/aislamiento & purificación , Bacterias/metabolismo , Fermentación , Lolium/microbiología , Ensilaje/microbiología , Aerobiosis , Bacterias/genética , Lactobacillus/genética , Polimorfismo de Longitud del Fragmento de Restricción , ARN Bacteriano/genética , ARN Ribosómico 16S/genéticaRESUMEN
OBJECTIVE: To evaluate the need for postnatal neurosurgical intervention after fetoscopic patch coverage of spina bifida aperta (SBA). METHODS: This was a retrospective analysis of a cohort of 71 fetuses which underwent minimally invasive fetoscopic patch coverage of SBA between 21 + 0 and 29 + 1 weeks of gestation. Postnatal neurosurgical procedures were classified into two types: re-coverage of the SBA within the first 3 months following birth, and shunt placement as treatment of associated hydrocephalus within the first year. RESULTS: Location of the SBA was lumbosacral in 59 cases, lumbar in seven, thoracic in three and sacral in two. In total, 20/71 (28%) patients underwent early postnatal neurosurgical intervention by means of re-coverage of the SBA. This was performed because of cerebrospinal fluid leakage in seven (35%), adhesions with functional deterioration in three (15%), incomplete coverage in five (25%) and skin defect in five (25%) cases. Ventriculoperitoneal shunt placement within 1 year was required in 32 (45%) cases and was preceded by ventriculostomy in two. Three (4%) infants needed Chiari decompression surgery in the first 12 months following birth, because of syringomyelia or gait disturbance. CONCLUSIONS: Fetoscopic patch coverage of SBA may require postnatal re-coverage in some cases. In most cases, conservative wound treatment shows good results, without requiring neurosurgical intervention. The low 1-year-shunt rate is comparable to data of the Management of Myelomeningocele Study and lower compared with published data of patients with postnatal only coverage of SBA.
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Fetoscopía/efectos adversos , Feto/cirugía , Procedimientos Neuroquirúrgicos/métodos , Espina Bífida Quística/cirugía , Femenino , Fetoscopía/métodos , Edad Gestacional , Humanos , Hidrocefalia/etiología , Hidrocefalia/cirugía , Lactante , Recién Nacido , Región Lumbosacra/embriología , Región Lumbosacra/cirugía , Atención Posnatal/métodos , Embarazo , Reoperación/métodos , Estudios Retrospectivos , Espina Bífida Quística/complicaciones , Espina Bífida Quística/embriología , Derivación VentriculoperitonealRESUMEN
BACKGROUND: Research applying psychological behaviour change theories to hand hygiene compliance is scarce, especially for physicians. AIM: To identify psychosocial determinants of self-reported hand hygiene behaviour (HHB) of physicians and nurses in intensive care units (ICUs). METHODS: A cross-sectional survey using a self-administered questionnaire that applied concepts from the Health Action Process Approach on hygienic hand disinfection was conducted in 10 ICUs and two haematopoietic stem cell transplantation units at Hannover Medical School, Germany. Self-reported compliance was operationalized as always disinfecting one's hands when given tasks associated with risk of infection. Using seven-point Likert scales, behavioural planning, maintenance self-efficacy and action control were assessed as psychological factors, and personnel and material resources, organizational problems and cooperation on the ward were assessed as perceived environmental factors. Multiple logistic regression analysis was employed. FINDINGS: In total, 307 physicians and 348 nurses participated in this study (response rates 70.9% and 63.4%, respectively). Self-reported compliance did not differ between the groups (72.4% vs 69.4%, P = 0.405). While nurses reported stronger planning, self-efficacy and action control, physicians indicated better personnel resources and cooperation on the ward (P < 0.02). Self-efficacy [odds ratio (OR) 1.4, P = 0.041], action control (OR 1.8, P < 0.001) and cooperation on the ward (OR 1.5, P = 0.036) were positively associated with HHB among physicians, but only action control was positively associated with HHB among nurses (OR 1.6, P < 0.001). CONCLUSION: The associations between action control (self-regulatory strategies where behaviour is evaluated continuously and automatically against guidelines) and compliance indicate that HHB is a habit in need of self-monitoring. The fact that perceived cooperation on the ward was the only environmental correlate of HHB among physicians stresses the importance of team-directed interventions.
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Desinfección de las Manos/métodos , Unidades de Cuidados Intensivos/estadística & datos numéricos , Enfermeras y Enfermeros/psicología , Médicos/psicología , Autoinforme , Adolescente , Adulto , Estudios Transversales , Femenino , Alemania , Adhesión a Directriz , Hospitales , Humanos , Masculino , Persona de Mediana Edad , Enfermeras y Enfermeros/estadística & datos numéricos , Médicos/estadística & datos numéricos , Encuestas y Cuestionarios , Adulto JovenRESUMEN
AIM: The extracellular matrix protein ED-B fibronectin (ED-B) is upregulated in inflammatory atherosclerotic lesions. However, functional in vivo imaging of ED-B-containing plaques has not been explored. This study evaluated whether [(99m)Tc]-conjugated AP39 ([(99m)Tc]-AP39), a single-chain antibody specific to ED-B, can be used for in vivo detection of atherosclerotic plaques in Western diet (WD)-fed, apolipoprotein E-deficient (apoE-/-) mice as compared to wildtype (WT) control mice. METHODS: Using SPECT, 12-month-old WD-fed apoE-/- and WT mice were studied 4 hours after injecting [(99m)Tc]-AP39 (148 MBq). Subsequently, mice were sacrificed, thoracic aortas measured in a g-counter, and plaques analyzed using histology, immuno-histochemistry, autoradiography, and morphometry. RESULTS: In vivo [(99m)Tc]-AP39-SPECT imaging of apoE-/- mice demonstrated a significant signal activity in the plaque-ridden thoracic aorta (52.236 ± 40.646 cpm/cm³) that co-localized with the aortic arch and the supra-aortic arteries in MRI scans. Low signal activity (9.468 ± 4.976 cpm/cm³) was observed in WT mice. In apoE-/- mice, the strongest signals were detected in the aortic root, aortic arch and along the abdominal aorta. Autoradiography analysis of aortas from apoE-/- mice confirmed the in vivo observation by demonstrating signal localization in atherosclerotic plaques. The size of autoradiography-positive plaque areas correlated significantly with the size of ED-B-positive (r=0.645, P=0.044) or macrophage-infiltrated (r=0.84, P<0.002) plaques. A significant correlation was found between the sizes of ED-B-positive and macrophage-infiltrated plaque areas (r=0.93, P<0.01). CONCLUSION: [(99m)Tc]-AP39-SPECT in vivo imaging detects inflammatory plaque lesions in WD-fed apoE-/- mice.
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Anticuerpos Monoclonales/farmacocinética , Aterosclerosis/diagnóstico por imagen , Aterosclerosis/metabolismo , Fibronectinas/metabolismo , Aumento de la Imagen/métodos , Tomografía Computarizada de Emisión de Fotón Único/métodos , Animales , Enfermedades de la Aorta/diagnóstico por imagen , Enfermedades de la Aorta/metabolismo , Apolipoproteínas E/genética , Biomarcadores/sangre , Ratones , Ratones Noqueados , Imagen Molecular/métodos , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Tecnecio/farmacocinéticaRESUMEN
BACKGROUND AND AIM: Hand hygiene practice is one of the most effective measures to prevent healthcare-associated infections. This study examines the trends of hand hygiene compliance among physicians and nurses on the intensive care units (ICU) and hematopoetic stem cell transplantation units (HSCTU) at Hannover Medical School. An observational study via repeated cross-sectional assessments was conducted during the first 6 years of the "AKTION Saubere Hände" (ASH), i.e. the German adaptation of WHO's "Clean Care is Safer Care" campaign. METHODS: Compliance rates were directly observed in accordance with WHO definitions on the 10 ICU and two HSCTU. Overall, 13,175 hand hygiene opportunities were observed between 2008 and 2013. RESULTS: In 2008, compliance rates of physicians and nurses did not differ significantly in statistical terms (53% vs. 57%, p=0.085). Physicians' compliance improved to 64% in 2011, but declined again to 48.4% in 2013 (p < 0.001). In contrast, hand hygiene compliance among nurses had increased to 71.3% as soon as 2009â/10 (p < 0.001). Their compliance dropped to 55.8% in 2013 and thus to baseline level (p=0.444), while remaining higher than that of physicians (p=0.003). Similar trends pertained to the surgical ICU. CONCLUSIONS: These results indicate that during the ASH-campaign hand hygiene compliance increased initially both among physicians and nurses, albeit so far not in a sustainable fashion. This implies an increased demand for interventions which not only promote motivation, but also its translation into stable and sustained behavior in accordance with guidelines.
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Centros Médicos Académicos/normas , Adhesión a Directriz/estadística & datos numéricos , Higiene de las Manos/normas , Unidades de Cuidados Intensivos/normas , Pautas de la Práctica en Enfermería/estadística & datos numéricos , Centros Médicos Académicos/estadística & datos numéricos , Alemania , Higiene de las Manos/estadística & datos numéricos , Unidades de Cuidados Intensivos/estadística & datos numéricos , Guías de Práctica Clínica como Asunto , Pautas de la Práctica en Enfermería/normas , Pautas de la Práctica en Medicina/normas , Pautas de la Práctica en Medicina/estadística & datos numéricos , Servicio de Cirugía en Hospital/normas , Servicio de Cirugía en Hospital/estadística & datos numéricosRESUMEN
AIMS: To evaluate the potential contribution of maternal glucose and lipids to fetal metabolic variables and growth in pregnancies with normal glucose tolerance in comparison with pregnancies with well-controlled gestational diabetes previously reported by us. METHODS: In 190 pregnancies with normal oral glucose tolerance tests (controls), insulin, glucose and lipid components were determined in maternal and arterial cord blood serum. Birthweight and neonatal fat mass were obtained after delivery. Values were adjusted for maternal pre-pregnancy BMI, Caesarean section and gestational age. Measurements were compared with those of gestational diabetes previously reported. RESULTS: Maternal serum glucose, triacylglycerol, free fatty acid and cholesterol levels did not differ between control pregnancies and those with gestational diabetes, whereas insulin, homeostasis model assessment and glycerol values were significantly lower in the former (2.6 vs. 5.6 µmol/l and 176 vs. 193 µmol/l, respectively). In contrast, cord blood glucose and free fatty acids were significantly lower in control pregnancies than in those with gestational diabetes (3.9 vs. 4.4 mmol/l and 80.7 vs. 137 µmol/l, respectively); the same was valid for insulin (0.03 vs. 0.05 nmol/l) and homeostasis model assessment (1.0 vs. 1.87). In control pregnancies, maternal serum glucose, free fatty acids and glycerol correlated with those in cord blood, but not with neonatal weight and fat mass, as seen for free fatty acids in those with gestational diabetes. The negative correlation between cord blood triacylglycerols and neonatal weight or fat mass previously reported in gestational diabetes could not be confirmed in control pregnancies, where all fetal lipids showed a positive correlation to neonatal anthropometrics. CONCLUSION: In normal pregnancies, in contrast to those with gestational diabetes, maternal lipids do not influence neonatal weight. Similar levels of maternal lipids in pregnancies with gestational diabetes and control pregnancies, but higher free fatty acids in the cord blood of those with gestational diabetes, indicate their enhanced placental transport and/or enhanced lipolysis as a result of decreased fetal insulin responsiveness.
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Diabetes Gestacional/metabolismo , Ácidos Grasos no Esterificados/metabolismo , Sangre Fetal/metabolismo , Hemoglobina Glucada/metabolismo , Lípidos/sangre , Intercambio Materno-Fetal , Triglicéridos/metabolismo , Adulto , Berlin , Peso al Nacer , Femenino , Desarrollo Fetal , Prueba de Tolerancia a la Glucosa , Humanos , EmbarazoRESUMEN
Surgical site infections (SSI) are a severe complication following surgical or orthopaedic procedures and are associated with significant increases in hospital length of stay (LOS), additional costs, morbidity and mortality. Hence, the prevention of SSI is essential and poses a major challenge in the healthcare system. Strategies and key points are presented and discussed. Infection control measures such as active surveillance of SSI, implementation of a checklist, compliance observations and instruction/training of healthcare workers as well as Staphylococcus aureus/MRSA screening, clipping instead of shaving, adherence to perioperative antibiotic prophylaxis, maintaining intraoperative normothermia and blood glucose control are essential for a comprehensive bundle in order to prevent SSI.
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Infección de la Herida Quirúrgica/etiología , Infección de la Herida Quirúrgica/prevención & control , Heridas y Lesiones/cirugía , Alemania , Humanos , Infección de la Herida Quirúrgica/diagnóstico , Traumatología/tendenciasRESUMEN
BACKGROUND: So-called polyphasic nosocomial outbreaks describe a situation in which additional infections occur after a certain case-free interval - despite the detection of the outbreak's source. This article summarises the results of a systematic search of the medical literature on polyphasic outbreaks. MATERIALS AND METHODS: For this purpose, the Outbreak Worldwide-Database, PubMed and reference lists of relevant articles were screened. RESULTS: A total of 124 polyphasic outbreaks (median duration of 50 weeks) was included in the analysis and then compared to 2089 monophasic nosocomial outbreaks. Surgical departments were significantly more often involved in polyphasic outbreaks than they were in monophasic events (33.9 % vs. 24.5 %; p < 0.05). Hepatitis B virus outbreaks were significantly more often seen as poly-phasic events. Either there had been more than one source initially, or a new source developed during the first phase of the outbreak and led to additional cases thereafter. CONCLUSIONS: Up to now, only little is known about polyphasic nosocomial outbreaks. Thus, there is a further need to close this gap of information in the future. Personnel on the ward as well as -infection control staff should always consider the possibility of the existence of more than one -source when investigating a nosocomial outbreak.
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Infección Hospitalaria/epidemiología , Brotes de Enfermedades/estadística & datos numéricos , Servicio de Cirugía en Hospital/estadística & datos numéricos , Infecciones Bacterianas/epidemiología , Infecciones Bacterianas/prevención & control , Infecciones Bacterianas/transmisión , Portador Sano , Trazado de Contacto , Infección Hospitalaria/prevención & control , Infección Hospitalaria/transmisión , Comparación Transcultural , Estudios Transversales , Brotes de Enfermedades/prevención & control , Encuestas Epidemiológicas , Hepatitis B/epidemiología , Humanos , Micosis/epidemiología , Micosis/prevención & control , Micosis/transmisión , Garantía de la Calidad de Atención de Salud , Recurrencia , Gestión de Riesgos , Virosis/epidemiología , Virosis/prevención & control , Virosis/transmisiónRESUMEN
Nosocomial infections with meticillin-resistant Staphylococcus aureus (MRSA) lead to increased health and economic costs. The purpose of this study was to determine costs for nosocomial MRSA pneumonia compared with meticillin-susceptible S. aureus (MSSA) pneumonia. A case-control study was conducted with patients who acquired nosocomial pneumonia with either MRSA or MSSA between January 2005 and December 2007. Patients were matched for age, severity of underlying disease, stay on intensive care units and non-intensive care units, admission and discharge within the same year, and in-hospital stay at least as long as that of cases before MRSA pneumonia. Our analysis includes 82 patients (41 cases, 41 controls). The overall costs for patients with nosocomial MRSA pneumonia were significantly higher than for patients with MSSA pneumonia (60,684 vs 38,731; P=0.01). The attributable costs for MRSA pneumonia per patient were 17,282 (P<0.001). The financial loss was higher for patients with MRSA pneumonia than for patients with MSSA pneumonia (11,704 vs 2,662; P=0.002). More cases died than controls while in the hospital (13 vs 1 death, P<0.001). Hospital personnel should be aware of the attributable costs of MRSA pneumonia, and should implement control measures to prevent MRSA transmission.
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Infección Hospitalaria/economía , Staphylococcus aureus Resistente a Meticilina/aislamiento & purificación , Neumonía Estafilocócica/economía , Anciano , Estudios de Casos y Controles , Femenino , Costos de la Atención en Salud , Humanos , Masculino , Persona de Mediana EdadRESUMEN
A design for a manipulator system for manipulating bare scanning tunneling microscopy (STM) tips without any tip holder is presented. The extremely stiff and rigid system consists of an ultrahigh vacuum compatible fully three-dimensionally movable gripper module driven by stepping motors and piezomotors. The tips are clamped by hardened tool steel gripper jaws, which are controlled by a stepping motor through levers. The system allows the reproducible manipulation of bare tungsten tips made of wires with diameters of 0.25 nm and having length of only up to 3 mm without damaging the tip or the STM. The tip manipulators' advantage is that the total mass of the scanning piezotube is reduced by removing the mass of a separate tip holder. Thereby, it becomes possible to further increase the resonance frequencies of the STM.
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Ascitis/terapia , Cateterismo/métodos , Catéteres de Permanencia , Ascitis/etiología , Cateterismo/instrumentación , Catéteres de Permanencia/normas , Contraindicaciones , Drenaje/instrumentación , Drenaje/métodos , Humanos , Consentimiento Informado , Cirrosis Hepática/complicaciones , Neoplasias/complicaciones , Cuidados Paliativos/métodosRESUMEN
BACKGROUND: Hand disinfection is a well-known and appropriate practise for infection prevention. Hence, it is logical to encourage its compliance and to provide its sustainability in the daily routine of a hospital. Several campaigns address an improvement of this important prevention measure. METHODS: In the Hannover Medical School the health staffs on the intensive care units and bone marrow transplantation wards were examined for this topic by a standardised questionnaire. The aim was to detect deficiencies and the level of knowledge. RESULTS: The forms were handed out to 838 health-care workers on 12 wards. 346 (41.2 %) were analysed. Inadequate hand disinfection due to a lack of time was the most common answer (43.1 %), followed by "there is no reason" (37.3 %). The alcoholic hand rub should be better available (50.3 %) and a continuing education programme should be provided (42.8 %) for improving hand hygiene practise. CONCLUSION: The survey revealed the known risk factors for non-compliance. At this point, the national hand campaign "Aktion Saubere Hände" supports training courses by providing instruction materials for all participants. These materials are used for training health-care workers individually.
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Actitud del Personal de Salud , Adhesión a Directriz/estadística & datos numéricos , Desinfección de las Manos/normas , Conocimientos, Actitudes y Práctica en Salud , Cuerpo Médico/estadística & datos numéricos , Pautas de la Práctica en Medicina/estadística & datos numéricos , Encuestas y Cuestionarios , AlemaniaAsunto(s)
Clostridioides difficile/aislamiento & purificación , Infección Hospitalaria/epidemiología , Infección Hospitalaria/microbiología , Brotes de Enfermedades , Enterocolitis Seudomembranosa/epidemiología , Enterocolitis Seudomembranosa/microbiología , Anciano , Femenino , Alemania/epidemiología , Hospitales Universitarios , Humanos , MasculinoRESUMEN
Critical illness polyneuropathy (CIP) occurs in association with sepsis and multiple organ failure; however, little is known about the pathomechanisms of CIP and its therapy. In order to determine the parameters which interfere with development of CIP, electrophysiological investigations of peripheral nerves and biochemical measures were correlated to each other. The present study includes 20 consecutive patients in an intensive care unit developing severe sepsis or septic shock. Nerve conduction studies and electromyography were performed with occurring sepsis (day 1, 7, 14) and neurophysiological parameters were correlated with biochemical measures, especially indicators of infection and inflammation. It was found that all patients developed neurophysiological signs of axonal motor polyneuropathy. There was a significant correlation between serum concentrations of endotoxin and interleukin-2 receptors (IL2-R) and reduction of the amplitude of the compound motor action potentials. Other clinical and biochemical parameters showed no significant correlations with neurophysiological data. This finding apparently indicates that endotoxin damages nerve axons directly or indirectly, e.g. by activation of inflammatory cascades (IL2-R). Endotoxin appears to be an essential factor in the pathogenesis of CIP in sepsis, and therapeutic options neutralizing endotoxin may prevent development of CIP.
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Enfermedad Crítica , Endotoxinas/toxicidad , Polineuropatías/etiología , Sepsis/complicaciones , Axones/patología , Estimulación Eléctrica , Electromiografía , Bacterias Gramnegativas/metabolismo , Humanos , Inflamación/patología , Neuronas Motoras/fisiología , Conducción Nerviosa/fisiología , Examen Neurológico , Neuronas Aferentes/fisiología , Nervios Periféricos/patología , Polineuropatías/patología , Receptores de Interleucina-2/efectos de los fármacos , Receptores de Interleucina-2/metabolismoRESUMEN
We study how a local air plasma treatment affects the mechanical properties of polystyrene by performing indentation measurements on the polymer in the elastic and plastic regime. The local exposure to plasma was obtained by placing a shadow-mask with quadratic holes of 45 x 45 microm(2) on top of the polymer substrate, providing uncovered (exposed to the plasma) and covered (protected from the plasma) areas. We have analyzed quantitatively the topography and the elastic-plastic properties of such a sample with atomic force microscopy (AFM) measurements, both before and after plasma treatment. To enhance the differences between covered and uncovered areas, the sample has been exposed to solvent vapor. This generates regions which are differently swollen. The quantitative investigation of the mechanical properties of the swollen sample for different solvent exposure times gives further insight into the changes of polystyrene mechanical properties caused by the plasma.
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Cleft lip with or without cleft palate (CL/P) is a congenital anomaly with variable birth prevalence based on geographic origins, with the highest rates commonly found in Asian populations. About 70% of cases are nonsyndromic (NS), in which the affected individual has no other abnormalities. NS CL/P is a complex disorder with genetic and environmental effects and no specific genetic loci yet confirmed. Fifteen candidate regions were examined for linkage to NS CL/P. Regions were chosen based on previous suggestive linkage and/or association in human families, or suggestive animal model data. Polymorphic markers in these regions were genotyped for analysis on 36 Filipino families comprised of 126 affected and 218 unaffected individuals. An additional 70 families with 149 affecteds were used for replication of suggestive results. Parametric (LOD score) and nonparametric (SIMIBD) linkage analyses were performed as well as transmission disequilibrium test (TDT) analysis. Five markers yielded suggestive results from the 36 families. The parametric LOD scores for the MSX1-CA and D4S1629 were >1.0 and the SIMIBD P values for D6S1029 and RFC1 are suggestive (<0.06), while the SIMIBD P value of 0.01 for TGFA was significant. Since the Msx1 mouse knockout has cleft palate and MSX1 mutations have been found in rare cases of syndromic CL/P, this locus is especially plausible for linkage. Previous studies have also found linkage of NS CL/P to 4q31 and 6p23. These regions contain several candidate genes, including AP2 at 6p23 and FGF2, BMPR1B, and MADH1 at 4q31. TGFA has both linkage and linkage disequilibrium data supporting it as a candidate gene for NS CL/P. While no region was definitively confirmed for linkage to NS CL/P, the data do support further investigation using larger sample sizes and candidate gene studies at 2p13.2, 4p16.2, 4q31, 6p23, and 16q22-24.
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Labio Leporino/genética , Fisura del Paladar/genética , Predisposición Genética a la Enfermedad/genética , Mapeo Cromosómico/métodos , Labio Leporino/patología , Fisura del Paladar/patología , Salud de la Familia , Femenino , Genotipo , Humanos , Desequilibrio de Ligamiento , Escala de Lod , Masculino , Repeticiones de Microsatélite , Linaje , FilipinasRESUMEN
This in vitro study evaluated the effect of metal alloys on three-body wear resistance of enamel and dentin, and vice versa. Three-body wear of human enamel, dentin, a soft gold alloy (BiOcclus Inlay), a CoCr alloy (Remanium 2000), a resin cement (Variolink II) and a zinc oxide phosphate cement (Harvard) was investigated using the ACTA-machine. Sample chambers of eight sample wheels were prepared with pure materials or combinations of human tooth substance, alloys and cement, simulating an inlay-like situation. After 100,000 and 200,000 cycles in a millet suspension with a spring force of 20 N, the amount of abraded material was profilometrically measured and evaluated by 3D surface data analysis. After 200,000 cycles, the materials demonstrated a mean loss of 0.41 microm for CoCr, 51 microm for gold, 57 microm for enamel, 164 microm for dentin, 79 microm for Variolink and 369 microm for Harvard. Using ANOVA and the Games-Howell-test, resin cement, enamel and gold were a subset not shown to differ, as was zinc phosphate cement and dentin. CoCr demonstrated the least wear and differed significantly from all materials. Enamel wear was significantly reduced in mixed chambers with CoCr, and gold after 200,000 cycles compared to enamel in pure chambers. In summary, a soft gold alloy can be recommended for inlays when considering three-body abrasion since the wear rate of the "soft" gold alloy corresponded to that of human enamel.
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Aleaciones Dentales/química , Esmalte Dental/patología , Dentina/patología , Incrustaciones , Abrasión de los Dientes/patología , Grabado Ácido Dental , Análisis de Varianza , Distribución de Chi-Cuadrado , Aleaciones de Cromo/química , Resinas Compuestas , Alisadura de la Restauración Dental , Aleaciones de Oro/química , Humanos , Microscopía Electrónica de Rastreo , Cementos de Resina/química , Estadística como Asunto , Estrés Mecánico , Propiedades de Superficie , Cemento de Fosfato de Zinc/químicaRESUMEN
Tumor necrosis factor alpha (TNFalpha) interferes with insulin signaling in adipose tissue and may promote insulin resistance. Insulin resistance is associated with vascular injury, but little is known about the interaction of TNFalpha and insulin in the vasculature. By activating the Insulin receptor (IR) --> IRS-1 --> phosphatidylinositol-3-kinase (PI3K) --> Akt-pathway, insulin protects vascular smooth muscle cells (VSMC) from undergoing apoptosis. We therefore investigated the effect of TNFalpha on insulin's antiapoptotic signaling in rat aortic VSMC. Insulin induced rapid tyrosine-phosphorylation of the IR and IRS-1 and caused a 2.8-fold increase of IRS-1-bound PI3K. TNFalpha had no effect on insulin-induced tyrosine-phosphorylation of IR or IRS-1, but inhibited insulin-stimulated IRS-1/PI3K-association by 84%. Insulin-induced phosphorylation of Akt downstream of PI3K was inhibited by TNFalpha in a similar pattern. We next examined the effect of TNFalpha on insulin's protective actions on H(2)O(2)-induced apoptosis. Insulin alone prevented 72.8% of H(2)O(2)-induced apoptosis, which was significantly inhibited by TNFalpha. TNFalpha alone did not induce apoptosis. In contrast, TNFalpha had no effect on PDGF-induced antiapoptotic signal transduction via Akt. Thus, TNFalpha selectively interferes with insulin's antiapoptotic signaling in VSMC by inhibiting the association of IRS-1/PI3K and the downstream activation of Akt.
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Apoptosis , Endotelio Vascular/metabolismo , Insulina/metabolismo , Músculo Liso/citología , Tiazolidinedionas , Factor de Necrosis Tumoral alfa/metabolismo , Animales , Aorta/citología , Western Blotting , Células Cultivadas , Activación Enzimática , Citometría de Flujo , Peróxido de Hidrógeno/farmacología , Proteínas Quinasas Activadas por Mitógenos/metabolismo , Fosfatidilinositol 3-Quinasas/metabolismo , Fosforilación , Pruebas de Precipitina , Unión Proteica , Ratas , Ratas Sprague-Dawley , Transducción de Señal , Tiazoles/farmacología , Factores de TiempoRESUMEN
Monocyte chemotactic protein 1 (MCP-1)-directed transendothelial migration of monocytes plays a key role in the early development of atherosclerosis. Migration of monocytes requires degradation of extracellular matrices, a process that involves matrix metalloproteinases (MMP) and tissue inhibitors of MMPs (TIMP). Recent studies suggest that the alpha1-adrenergic receptor antagonist doxazosin (Dox) might have antiatherosclerotic effects, although the underlying mechanisms are poorly understood. The purpose of the present study was to determine the effects of Dox on MCP-1-directed monocyte migration, MMP-9 activity, and TIMP-1 expression. MCP-1 (50 ng/ml) stimulated migration of human peripheral blood monocytes (HPBM) 2.7+/-0.42-fold and THP-1 human monocytes 5.9+/-0.83-fold compared with unstimulated control. Dox inhibited MCP-1-induced migration in a dose-dependent manner, with a maximal reduction at 10 microM of 69.5+/-5.9% in HPBM and 72.2+/-3.2% in THP-1 cells. Dox blocked migration even after pretreatment with phenoxybenzamine, an irreversible alpha1-adrenergic receptor antagonist (HPBM: phenoxybenzamine 1 microM + Dox 10 microM, 71.9+/-2.2% inhibition; THP-1 cells: phenoxybenzamine 1 microM + Dox 10 microM: 78+/-7.7% inhibition), suggesting that the antimigratory activity of Dox is mediated through a novel mechanism unrelated to its blocking of the alpha1-adrenergic receptor. Dox (10 microM) inhibited MMP-9 activity by 67.6+/-10.5%, whereas MMP-9 protein levels were not affected. Also, Dox increased PMA-induced-tissue inhibitor of MMPs-1 (TIMP-1) expression by 134.4+/-6.6%. Dox 10 microM. The present study demonstrates a potential novel antiatherosclerotic action of Dox by blocking MCP-1-directed monocyte migration, which might be partly mediated by inhibition of MMP-9 activity.
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Antagonistas Adrenérgicos alfa/farmacología , Movimiento Celular/efectos de los fármacos , Quimiocina CCL2/antagonistas & inhibidores , Doxazosina/farmacología , Monocitos/efectos de los fármacos , Movimiento Celular/fisiología , Quimiocina CCL2/farmacología , Humanos , Metaloproteinasa 9 de la Matriz/efectos de los fármacos , Metaloproteinasa 9 de la Matriz/metabolismo , Monocitos/metabolismo , Inhibidor Tisular de Metaloproteinasa-1/efectos de los fármacos , Inhibidor Tisular de Metaloproteinasa-1/metabolismo , Células Tumorales CultivadasRESUMEN
The presence of an abscess in a pituitary tumor is a very rare finding. The authors report the case of a 69-year-old man with a pituitary adenoma confirmed by neuroimaging results, in whom a high fever, meningismus, and left-sided ophthalmoplegia developed 4 days after tooth extraction. The results of serial cranial magnetic resonance imaging were highly indicative of an abscess formation within the pituitary adenoma. During surgery the tumor was approached transsphenoidally and removed. Histological examination confirmed the presence of an abscess formation within the pituitary adenoma. It is most likely that the tooth extraction caused a bacteremia, which led to an inflammation with abscess formation within the pituitary adenoma. The authors conclude that invasive dental procedures should be avoided before planned resection of a pituitary adenoma.