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Honey bee is one of the most important insects considering its role in agriculture,ecology and economy as a whole. In this study, the genetic diversity of different Iranian honey bee populations was evaluated using inter simple sequence repeat (ISSR) markers. During May to September 2014, 108 young worker honey bees were collected from six different populations in 30 different geoclimatic locations from Golestan, Mazendaran, Guilan, West Azerbaijan, East Azerbaijan, Ardebil provinces of Iran. DNA was extracted from the worker honey bees. The quality and quantity of extracted DNA were measured. A set of ten primers were screened with the laboratory populations of honey bees. The number of fragments produced in the different honey bee populations varied from 3 to 10, varying within 150 to 1500 bp. The used ten ISSR primers generated 40 polymorphic fragments, and the average heterozygosity for each primer was 0.266. Maximum numbers of bands were recorded for primer A1. A dendrogram based on the Unweighted Pair Group Method with Arithmetic mean (UPGMA) method generated two sub-clusters. Honey bee populations of Golestan, Mazendaran, Guilan provinces were located in the first group. The second group included honey bee populations of Ardebil, West Azerbaijan, East Azerbaijan provinces, but this group showed a close relationship with other populations. The results showed obviously the ability of the ISSR marker technique to detect the genetic diversity among the honey bee populations.
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Abejas/genética , Variación Genética , Genética de Población , Repeticiones de Microsatélite/genética , Animales , Secuencia de Bases , Cartilla de ADN/metabolismo , Marcadores Genéticos , Genotipo , Geografía , Irán , Filogenia , Reacción en Cadena de la Polimerasa , Polimorfismo GenéticoRESUMEN
Recently, there are tendency to use natural products such as Ziziphus Jujube (Jujube) as therapeutic agents for cancer. Understanding the molecular mechanisms of anti-cancer effects of Jujube may improve the current therapeutic strategies against cervical cancer. Our MTT data showed a significant dose- and time-dependent inhibition of OV-2008 cell proliferation following Jujube administration. Moreover, qRT-PCR analyses significantly revealed the suppression of cyclin D1 and the enhancement of P53, P21 and P27 expression in treated cells. These results suggest that the herb exerts a cytotoxic effect on cervical cancer cells through alternation of the expression of the genes that are involved in regulation of cell cycle.
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Antineoplásicos Fitogénicos/farmacología , Ciclo Celular/efectos de los fármacos , Células Epiteliales/efectos de los fármacos , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Ziziphus/química , Antineoplásicos Fitogénicos/aislamiento & purificación , Ciclo Celular/genética , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Cuello del Útero/efectos de los fármacos , Cuello del Útero/metabolismo , Cuello del Útero/patología , Ciclina D1/antagonistas & inhibidores , Ciclina D1/genética , Ciclina D1/metabolismo , Inhibidor p21 de las Quinasas Dependientes de la Ciclina/agonistas , Inhibidor p21 de las Quinasas Dependientes de la Ciclina/genética , Inhibidor p21 de las Quinasas Dependientes de la Ciclina/metabolismo , Inhibidor p27 de las Quinasas Dependientes de la Ciclina/agonistas , Inhibidor p27 de las Quinasas Dependientes de la Ciclina/genética , Inhibidor p27 de las Quinasas Dependientes de la Ciclina/metabolismo , Relación Dosis-Respuesta a Droga , Células Epiteliales/metabolismo , Células Epiteliales/patología , Femenino , Frutas/química , Humanos , Extractos Vegetales/química , Transducción de Señal , Proteína p53 Supresora de Tumor/agonistas , Proteína p53 Supresora de Tumor/genética , Proteína p53 Supresora de Tumor/metabolismoRESUMEN
The Ras/RAF/MEK/ERK1/2 pathway is important in the control of growth signals, differentiation and cell survival. Over-expression and activation of this pathway have been reported in different types of cancer. This study analyses the promoter methylation and RNA expression profiles of ERK and RAF1 genes with risk of oral squamous cell carcinoma (OSCC) along with the promoter methylation status of ERK and RAF1 genes using a methylation-specific polymerase chain reaction (MS-PCR) in 86 paraffin-wax embedded samples of OSCC and 68 normal control tissues. Furthermore, ERK and RAF1 expression was analysed in 19 cases and 20 normal samples by real-time reverse transcription PCR. Frequency of promoter methylation was detected for ERK (93.02% and 6.98%) and RAF1 (95.35% and 4.65%) genes in cases and controls, respectively. Messenger RNA (mRNA) expression analysis indicated statistically significant difference between cases and controls for ERK (P < 0.002) and RAF1 (P < 0.006). The authors believe that this is the first report to show that expression of ERK and RAF1 is involved in risk of OSCC.
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Carcinoma de Células Escamosas/genética , Metilación de ADN , Quinasas MAP Reguladas por Señal Extracelular/genética , Neoplasias de Cabeza y Cuello/genética , Neoplasias de la Boca/genética , Proteínas Proto-Oncogénicas c-raf/genética , Adulto , Anciano , Carcinoma de Células Escamosas/enzimología , Estudios de Casos y Controles , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Femenino , Perfilación de la Expresión Génica , Neoplasias de Cabeza y Cuello/enzimología , Humanos , Masculino , Persona de Mediana Edad , Neoplasias de la Boca/enzimología , Regiones Promotoras Genéticas , Proteínas Proto-Oncogénicas c-raf/metabolismo , Carcinoma de Células Escamosas de Cabeza y CuelloRESUMEN
The deposition of noble metals on soft and/or flexible substrates is vital for several emerging applications including flexible electronics and the fabrication of soft bionic implants. In this paper, we describe a new strategy for the deposition of platinum electrodes on a range of materials, including insulators and flexible polymers. The strategy is enabled by two principle advances: (1) the introduction of a novel, low temperature strategy for reducing chloroplatinic acid to platinum using nitrogen plasma; (2) the development of a chloroplatinic acid based liquid ink formulation, utilizing ethylene glycol as both ink carrier and reducing agent, for versatile printing at nanoscale resolution using dip-pen nanolithography (DPN). The ink formulation has been printed and reduced upon Si, glass, ITO, Ge, PDMS, and Parylene C. The plasma treatment effects reduction of the precursor patterns in situ without subjecting the substrate to destructively high temperatures. Feature size is controlled via dwell time and degree of ink loading, and platinum features with 60 nm dimensions could be routinely achieved on Si. Reduction of the ink to platinum was confirmed by energy dispersive x-ray spectroscopy (EDS) elemental analysis and x-ray diffraction (XRD) measurements. Feature morphology was characterized by optical microscopy, SEM and AFM. The high electrochemical activity of individually printed Pt features was characterized using scanning electrochemical microscopy (SECM).
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BACKGROUND: Rabies is endemic in low- and middle-income countries. It is caused mainly by the bite of a rabid dog and is fatal if not treated effectively and in a timely manner with quality post-exposure prophylaxis. Despite a profusion of private and public healthcare centres in Sindh province, most are ill-equipped to treat dog bites. METHODS: We analysed 129 human deaths from rabies who presented at the emergency departments of two tertiary care hospitals in Karachi over 10 y. Demographic data, time, location of the bite and distance travelled to report symptoms of rabies were recorded. RESULTS: Most victims were male, and children were more often affected; almost none had received post-exposure prophylaxis. A total of 12% of bites were on the face, head or neck. The mean incubation period was 56 d. Most (60%) of the rabies victims travelled long distances, hoping to receive treatment. CONCLUSIONS: Rabies deaths were either due to a lack of awareness or the non-availability of rabies immunobiologicals within easy reach. Public health services must raise awareness, conduct surveillance and provide appropriately spaced centres for free treatment of dog bites. This lethal disease must be prevented at all costs.
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Mordeduras y Picaduras , Rabia , Animales , Niño , Perros , Femenino , Humanos , Masculino , Mordeduras y Picaduras/complicaciones , Hospitales , Pakistán/epidemiología , Profilaxis Posexposición , Rabia/prevención & controlRESUMEN
Electron and hole spins in organic light-emitting diodes constitute prototypical two-level systems for the exploration of the ultrastrong-drive regime of light-matter interactions. Floquet solutions to the time-dependent Hamiltonian of pairs of electron and hole spins reveal that, under non-perturbative resonant drive, when spin-Rabi frequencies become comparable to the Larmor frequencies, hybrid light-matter states emerge that enable dipole-forbidden multi-quantum transitions at integer and fractional g-factors. To probe these phenomena experimentally, we develop an electrically detected magnetic-resonance experiment supporting oscillating driving fields comparable in amplitude to the static field defining the Zeeman splitting; and an organic semiconductor characterized by minimal local hyperfine fields allowing the non-perturbative light-matter interactions to be resolved. The experimental confirmation of the predicted Floquet states under strong-drive conditions demonstrates the presence of hybrid light-matter spin excitations at room temperature. These dressed states are insensitive to power broadening, display Bloch-Siegert-like shifts, and are suggestive of long spin coherence times, implying potential applicability for quantum sensing.
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The aim of the present study was to examine whether prone positioning (PP) affects ventilator associated-pneumonia (VAP) and mortality in patients with acute lung injury/adult respiratory distress syndrome. 2,409 prospectively included patients were admitted over 9 yrs (2000-2008) to 12 French intensive care units (ICUs) (OUTCOMEREA). The patients required invasive mechanical ventilation (MV) and had arterial oxygen tension/inspiratory oxygen fraction ratios <300 during the first 48 h. Controls were matched to PP patients on the PP propensity score (+/-10%), MV duration longer than that in PP patients before the first turn prone, and centre. VAP incidence was similar in the PP and control groups (24 versus 13 episodes.1,000 patient-days MV(-1) respectively, p = 0.14). After adjustment, PP did not decrease VAP occurrence (HR 1.64 (95% CI 0.70-3.84); p = 0.25) but significantly delayed hospital mortality (HR 0.56 (95% CI 0.39-0.79); p = 0.001), without decreasing 28-day mortality (37% in both groups). Post hoc analyses indicated that PP did not protect against VAP but, when used for >1 day, might decrease mortality and benefit the sickest patients (Simplified Acute Physiology Score >50). In ICU patients with hypoxaemic acute respiratory failure, PP had no effect on the risk of VAP. PP delayed mortality without decreasing 28-day mortality. PP >1 day might decrease mortality, particularly in the sickest patients.
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Hipoxia/mortalidad , Hipoxia/terapia , Neumonía , Posición Prona , Respiración Artificial/efectos adversos , Respiración Artificial/mortalidad , Enfermedad Aguda , Anciano , Estudios de Casos y Controles , Bases de Datos Factuales/estadística & datos numéricos , Femenino , Mortalidad Hospitalaria , Humanos , Incidencia , Unidades de Cuidados Intensivos/estadística & datos numéricos , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Neumonía/etiología , Neumonía/mortalidad , Neumonía/prevención & control , Valor Predictivo de las Pruebas , Modelos de Riesgos Proporcionales , Insuficiencia Respiratoria/mortalidad , Insuficiencia Respiratoria/terapia , Factores de RiesgoRESUMEN
BACKGROUND: Restless legs syndrome (RLS) is a neurological disorder characterized by an uncomfortable sensation in the legs which gets worse in the evening or night, relieved upon movement. The aim of this study was to specify the prevalence of RLS in the group of young medical students and to assess the effect of RLS on sleep, as sleep disturbance is one of the chief complaints of RLS patients. We also studied its association with smoking as it is considered an aggravating factor. METHOD: This was a cross-sectional study conducted from June 2017 to July 2018 in Karachi. A total of 300 students (220 females and 80 males) participated and were given questionnaires to detect RLS based on criteria proposed by the International Restless Legs Syndrome Study Group. Subjects who were positive for RLS were further asked questions about sleep by using the Epworth Sleepiness Scale and severity of RLS by using RLS Rating Scale. They were also asked about their smoking status. RESULTS: The frequency of RLS is 8% among young adults. Out of 300 medical students, 24 students were classified positive for RLS with a female preponderance (66.7% were females and 33.3% were males). The severity of RLS was more rated to be mild to moderate. The effect of RLS on sleep was in the mild range. The p value of smoking status comparing with gender came out to be <0.001, and p value of smoking status comparing with gender came out to be <0.001, and. CONCLUSION: It is concluded that we found RLS to be present significantly in our population that is without comorbidities. Our results showed female preponderance and a mild sleep disturbance in our study population. More attention is needed to recognize RLS and to manage the aggravating factors of RLS.
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The combined action of ultraviolet irradiation and microwave heating onto acetonitrile solution of [Re( NN )(CO)3 (NCMe)]OTf ( NN =phenantroline and neocuproine) afforded cis,trans-Re( NN )(CO)2 (NCMe)2 ]+ acetonitrile derivatives. Substitution of relatively labile NCMe with a series of aromatic N-donor ligands (pyridine, pyrazine, 4,4'-bipyridine, N-methyl-4,4'-bipyridine) gave a novel family of the diimine cis,trans-[Re( NN )(CO)2 (L)2 ]+ complexes. Photophysical studies of the obtained compounds in solution revealed unusually high absorption across the visible region and NIR phosphorescence with emission band maxima ranging from 711 to 805â nm. The nature of emissive excited states was studied using DFT calculations to show dominant contribution of 3 MLCT (dπ(Re)âπ*( NN )) character. Electrochemical (CV and DPV) studies of the monocationic diimine complexes revealed one reduction and one oxidation wave assigned to reduction of the diimine moiety and oxidation of the rhenium center, respectively.
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PURPOSE: To compare attenuation measurements and image quality of virtual unenhanced phase (VUP) images with those of conventional true unenhanced phase (TUP) images on spectral dual energy computed tomography (DECT) with dual layer detector on abdominal tissues and to assess potential reduction in radiation dose. MATERIAL AND METHOD: A total of 295 patients (185 men, 110 women; mean age 61±17.6 [SD] years [range: 17-95 years]) who had undergone abdominal or thoraco-abdominal CT with pre- and post-contrast imaging (portal phase) with spectral DECT with dual layer detector were retrospectively analyzed. VUP images based on portal-venous phase DECT acquisition were generated. Regions of interest were defined in abdominal tissues (liver, spleen, kidney, muscle and fat) by two independent readers. Inter-technique agreement (VUP images vs. TUP images) on attenuation measurements was assessed. Signal-to noise ratio (SNR) and image quality of TUP and VUP images were compared. The radiation dose delivered to patients was compared with the radiation dose of protocols without TUP images. RESULTS: A total of 9880 ROIs were drawn in the abdominal tissues. The difference in mean attenuation values between TUP and VUP images was less than 15 HU in 98.3% and less than 10 HU in 92.3% of all measurements. VUP images overestimated attenuation in fat comparatively to TUP images. Image quality was evaluated as good or excellent in 77% (37/48) of TUP images and 54% (26/48) of VUP images. Using VUP images instead of TUP images could decrease the radiation dose by 32%. CONCLUSION: VUP images demonstrate good agreement with TUP images in different abdominals tissues and can be obtained with similar image quality as TUP. VUP images appear as an alternative to TUP images, resulting in reduction of radiation dose delivered to the patient.
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Radiografía Abdominal/métodos , Imagen Radiográfica por Emisión de Doble Fotón/métodos , Tomografía Computarizada por Rayos X/métodos , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Medios de Contraste , Femenino , Humanos , Masculino , Persona de Mediana Edad , Dosis de Radiación , Interpretación de Imagen Radiográfica Asistida por Computador/métodos , Radiografía Torácica/métodos , Estudios Retrospectivos , Relación Señal-Ruido , Adulto JovenRESUMEN
BACKGROUND: Transient and persistent acute kidney injury (AKI) could share similar physiopathological mechanisms. The objective of our study was to assess prognostic impact of AKI duration on ICU mortality. DESIGN: Retrospective analysis of a prospective database via cause-specific model, with 28-day ICU mortality as primary end point, considering discharge alive as a competing event and taking into account time-dependent nature of renal recovery. Renal recovery was defined as a decrease of at least one KDIGO class compared to the previous day. SETTING: 23 French ICUs. PATIENTS: Patients of a French multicentric observational cohort were included if they suffered from AKI at ICU admission between 1996 and 2015. INTERVENTION: None. RESULTS: A total of 5242 patients were included. Initial severity according to KDIGO creatinine definition was AKI stage 1 for 2458 patients (46.89%), AKI stage 2 for 1181 (22.53%) and AKI stage 3 for 1603 (30.58%). Crude 28-day ICU mortality according to AKI severity was 22.74% (n = 559), 27.69% (n = 327) and 26.26% (n = 421), respectively. Renal recovery was experienced by 3085 patients (58.85%), and its rate was significantly different between AKI severity stages (P < 0.01). Twenty-eight-day ICU mortality was independently lower in patients experiencing renal recovery [CSHR 0.54 (95% CI 0.46-0.63), P < 0.01]. Lastly, RRT requirement was strongly associated with persistent AKI whichever threshold was chosen between day 2 and 7 to delineate transient from persistent AKI. CONCLUSIONS: Short-term renal recovery, according to several definitions, was independently associated with higher mortality and RRT requirement. Moreover, distinction between transient and persistent AKI is consequently a clinically relevant surrogate outcome variable for diagnostic testing in critically ill patients.
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PURPOSE: The goal of this study was to estimate the frequency and the quality of agreement studies published in diagnostic imaging journals. MATERIALS AND METHODS: All studies published between January 2011 and December 2012 in four radiology journals were reviewed. Four trained readers evaluated agreement studies using a 24-item form that included the 15 items of the Guidelines for Reporting Reliability and Agreement Studies criteria. RESULTS: Of 2229 source titles, 280 studies (13%) reported agreement. The mean number of patients per study was 81±99 (SD) (range, 0-180). Justification for sample size was found in 9 studies (3%). The number of raters was≤2 in 226 studies (81%). No intra-observer study was performed in 212 (76%) articles. Confidence intervals and interpretation of statistical estimates were provided in 98 (35%) and 147 (53%) of the studies, respectively. In 168 studies (60%), the agreement study was not mentioned in the discussion section. In 8 studies (3%), reporting of the agreement study was judged to be adequate. Twenty studies (7%) were dedicated to agreement. CONCLUSION: Agreement studies are preliminary and not adequately reported. Studies dedicated to agreement are infrequent. They are research opportunities that should be promoted.
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Consenso , Variaciones Dependientes del Observador , Radiografía , Proyectos de Investigación , HumanosRESUMEN
A mixture of the platinum(0) complex [Pt(PtBu3)2] and tetrakis(acetonitrile)copper(i) hexafluorophosphate in acetone activated a water molecule and gave the hydride platinum(ii) complex [PtH(CH3CN)(PtBu3)2]PF6, 1, and the hydroxide Cu(i) species. The crystal structure of complex 1 was determined by X-ray crystallography, indicating a distorted square planar geometry around the platinum center. Although three possible mechanisms are proposed for this transformation, monitoring of the reaction using NMR spectroscopy at low temperature reveals that a cooperative pathway involving formation of a Pt0-CuI dative bond complex is the most probable pathway. The hydride platinum complex 1 is stable in acidic and neutral conditions but undergoes intramolecular C-H activation in the presence of pyridine. Monitoring of the reaction using 1H and 31P NMR spectroscopy shows that a cyclometalation reaction of one of the phosphine ligands is followed by displacement of a second phosphine ligand by pyridine to give the cyclometalated platinum(ii) complex, [Pt(κ2PC-PtBu2CMe2CH2)(py)2], 4. The structure of 4 in solution and solid state phases was determined using NMR spectroscopy and X-ray crystallography, respectively.
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BACKGROUND AND PURPOSE: Patients treated with coiling are often followed by MR angiography. Our objective was to assess the inter- and intraobserver agreement in diagnosing aneurysm remnants and recurrences by using multimodality imaging, including TOF MRA. MATERIALS AND METHODS: A portfolio composed of 120 selected images from 56 patients was sent to 15 neuroradiologists from 10 institutions. For each case, raters were asked to classify angiographic results (3 classes) of 2 studies (32 MRA-MRA and 24 DSA-MRA pairs) and to provide a final judgment regarding the presence of a recurrence (no, minor, major). Six raters were asked to independently review the portfolio twice. A second study, restricted to 4 raters having full access to all images, was designed to validate the results of the electronic survey. RESULTS: The proportion of cases judged to have a major recurrence varied between 16.1% and 71.4% (mean, 35.0% ± 12.7%). There was moderate agreement overall (κ = 0.474 ± 0.009), increasing to nearly substantial (κ = 0.581 ± 0.014) when the judgment was dichotomized (presence or absence of a major recurrence). Agreement on cases followed-up by MRA-MRA was similarly substantial (κ = 0.601 ± 0.018). The intrarater agreement varied between fair (κ = 0.257 ± 0.093) and substantial (κ= 0.699 ± 0.084), improving with a dichotomized judgment concerning MRA-MRA comparisons. Agreement was no better when raters had access to all images. CONCLUSIONS: There is an important variability in the assessment of angiographic outcomes of endovascular treatments. Agreement on the presence of a major recurrence when comparing 2 MRA studies or the MRA with the last catheter angiographic study can be substantial.
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Aneurisma Intracraneal/diagnóstico por imagen , Aneurisma Intracraneal/cirugía , Angiografía por Resonancia Magnética/métodos , Neuroimagen/métodos , Angiografía de Substracción Digital/métodos , Embolización Terapéutica/métodos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Imagen Multimodal/métodos , Reproducibilidad de los Resultados , Resultado del TratamientoRESUMEN
BACKGROUND AND PURPOSE: Trichosporon is a genus of anamorphic basidiomycetous yeast which is widely distributed in nature and is found in tropical and temperate areas. The aim of this work was to study the isolation, identification and molecular analysis of Trichosporon species in soil. MATERIALS AND METHODS: In order to isolate and identify Trichosporon species in soil, 30 samples were collected from 30 different locations across Iran. The isolates were identified by means of the standard methods of yeast identification. To confirm morphological identification, genomic DNA was extracted and the hypervariable D1/D2 domain of the large-subunit (LSU) ribosomal DNA (rDNA) gene was amplified by polymerase chain reaction (PCR), using primer pair NL-1/NL-4, and then the sequences were analyzed. RESULTS: According to the morphological and physiological assessments, isolates were identified as T. coremiiforme. The isolates formed chlamydospore after one week on yeast-malt (YM) agar medium. Using Blast program, we found that the D1/D2 sequences of the T. coremiiforme isolates from Iran (accession no: KP055040 and KP055041) showed 99% homology with the T. coremiiforme deposited in GenBank. All the T. coremiiforme isolates placed in the Ovoides cluster were well-supported by bootstrap values. CONCLUSION: The present study is the first attempt to survey Trichosporon in soil of Iran. To the best of our knowledge, this is the first investigation of T. coremiiforme in Iran.
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BACKGROUND AND PURPOSE: The repeatability of head CT interpretations may be studied in different contexts: in peer-review quality assurance interventions or in interobserver agreement studies. We assessed the agreement between double-blind reports of outpatient CT scans in a routine academic practice. MATERIALS AND METHODS: Outpatient head CT scans (119 patients) were randomly selected to be read twice in a blinded fashion by 8 neuroradiologists practicing in an academic institution during 1 year. Nonstandardized reports were analyzed to extract 4 items (answer to the clinical question, major findings, incidental findings, recommendations for further investigations) from each report, to identify agreement or discrepancies (classified as class 2 [mentioned or not mentioned or contradictions between reports], class 1 [mentioned in both reports but diverging in location or severity], 0 [concordant], or not applicable), according to a standardized data-extraction form. Agreement regarding the presence or absence of clinically significant or incidental findings was studied with κ statistics. RESULTS: The interobserver agreement regarding head CT studies with positive and negative results for clinically pertinent findings was 0.86 (0.77-0.95), but concordance was only 75.6% (67.2%-82.5%). Class 2 discrepancy was found in 15.1%; class 1 discrepancy, in 9.2% of cases. The κ value for reporting incidental findings was 0.59 (0.45-0.74), with class 2 discrepancy in 29.4% of cases. Most discrepancies did not impact the clinical management of patients. CONCLUSIONS: Discrepancies in double-blind interpretations of head CT examinations were more common than reported in peer-review quality assurance programs.
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Encefalopatías/diagnóstico por imagen , Neurología/normas , Adulto , Anciano , Método Doble Ciego , Femenino , Cabeza , Humanos , Masculino , Persona de Mediana Edad , Variaciones Dependientes del Observador , Pacientes Ambulatorios , Médicos , Tomografía Computarizada por Rayos X/métodosRESUMEN
BACKGROUND AND PURPOSE: Porosity and pore density (PD) are important characteristics of flow diverters (FDs), because they may influence device efficacy and safety. Reliable measurement of these parameters would seem to be required for comparisons between devices, device selection at the time of clinical usage, as well as for research purposes. Because there is no standard method of measurement, our aim was to assess the intra-rater and inter-rater reliability of PD measurements and of three different ways of measuring porosity. METHODS: Six microphotographs of two fully deployed FDs were taken overlying two different millimetric reference grids: one flat and the other corrected to match the cylindrical stent. Standardized protocols for independently measuring PD and porosity according to three different methods were used by three trained observers and by the same observer twice. Bland-Altman plots and intra-class correlation coefficients (ICC) were used to study the reliability of the measurements. RESULTS: For porosity, satisfactory agreement occurred only when the same method of measurement was performed by the same observer. Intra-observer and inter-observer agreement were poor for measures of porosity when different methods were used (with differences in the range of 5-10%, ICC <0.6 for all methods). Measurement of PD was more reliable within (ICC 0.991 (0.946 to 0.999)) and between (ICC 0.945 (0.781 to 0.991)) observers. CONCLUSIONS: Without standardization, the porosity of different devices cannot reliably be compared because use of different methods or different observers substantially changes results. Pore density seems to be more reliably measured than porosity.
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Procedimientos Endovasculares/instrumentación , Porosidad , Prótesis e Implantes/normas , Diseño de Equipo , Humanos , Variaciones Dependientes del Observador , Reproducibilidad de los ResultadosRESUMEN
We investigated the spatiotemporal GFAP mRNA expression over a period of 11 days following brain injury in rats caused by impact acceleration, which is known to produce diffuse axonal injury (DAI). We observed widespread GFAP mRNA expression throughout the brain, which was more rapid and intense in the hippocampus. This expression was obvious in most animals 2 days after injury and appeared maximal at day 6. Although it decreased by day 11, the level of expression remained high compared with control levels. We noted slight differences in time of onset and the magnitude of the response between hippocampus and white matter structures or cortical areas. The different mechanisms able to trigger this response are discussed in regard to histopathological changes observed in DAI models.
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Proteína Ácida Fibrilar de la Glía/genética , Traumatismos Cerrados de la Cabeza/metabolismo , Hipocampo/metabolismo , Trastornos de la Memoria/metabolismo , ARN Mensajero/biosíntesis , Análisis de Varianza , Animales , Encéfalo/metabolismo , Traumatismos Cerrados de la Cabeza/psicología , Hipocampo/lesiones , Masculino , Trastornos de la Memoria/etiología , Ratas , Ratas Sprague-DawleyRESUMEN
OBJECTIVE: As hydratation of the normal brain is much more dictated by osmotic gradients than by hydrostatic or oncotic pressures, this study aimed to compare the effect of the infusion of currently used volume loading solutions on plasma osmolality. STUDY DESIGN: Randomized, comparative trial. PATIENTS: Thirty ASA 1-2 patients, scheduled for lumbar intervertebral disc surgery were randomly allocated to three groups receiving either 2,000 mL of lactated Ringer's solution (RL, n = 10), 750 mL of hydroxyethylstarch 6% (HEA, n = 10) or 2,000 mL of normal saline (NaCl, n = 10). METHODS: Baseline osmolality, natraemia, glycaemia and protidaemia were measured before induction of anaesthesia (T1), after the infusion of 375 mL of hydroxyethylstarch or 1,000 mL of crystalloids (T2) and at the end of the infusion (T3). RESULTS: The three groups were identical for age, weight, initial plasma osmolality and natraemia. However, osmolality in the RL group was decreased at T2 and T3 compared to T1 (respectively: 299 +/- 5 mOsm.kg-1, 295 +/- 4 mOsm.kg-1 and 292 +/- 5 mOsm.kg-1. Osmolality at T2 and T3 was also lower in the RL group compared to the HEA and NaCl groups (respectively: 301 +/- 6 mOsm.kg-1 and 304 +/- 13 mOsm.kg-1 for T2 and T3 in the HEA group, and 299 +/- 5 mOsm.kg-1 and 298 +/- 5 mOsm.kg-1 in the NaCl group). In the HEA and NaCl groups, osmolality was unchanged at T2 and T3 compared to T1. CONCLUSION: Both normal saline and hydroxyethylstarch 6% maintain plasma osmolality, whereas Ringer lactate tends to decrease it. For that reason normal saline and hetastarch 6% but not lactated Ringer's solution, may be administered in patients experiencing blood-brain barrier damage.