685 research outputs found

    Second-harmonic generation of ZnO nanoparticles synthesized by laser ablation of solids in liquids

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    We report the synthesis of small zinc oxide nanoparticles (ZnO NPs) based colloidal suspensions and the study of second-harmonic generation from aggregated ZnO NPs deposited on glass substrates. The colloidal suspensions were obtained using the laser ablation of solids in liquids technique, ablating a Zn solid target immersed in acetone as the liquid medium, with ns-laser pulses (1064 nm) of a Nd-YAG laser. The per pulse laser fluence, the laser repetition rate frequency and the ablation time were kept constant. The absorption evolution of the obtained suspensions was optically characterized through absorption spectroscopy until stabilization. Raman spectroscopy, SEM and HRTEM were used to provide evidence of the ZnO NPs structure. HRTEM results showed that 5–8 nm spheroids ZnO NPs were obtained. Strong second-harmonic signal is obtained from random ZnO monocrystalline NPs and from aggregated ZnO NPs, suggesting that the high efficiency of the nonlinear process may not depend on the NPs size or aggregation state

    Factores Asociados a Hemorragia Intraventricular En Neonatos Atendidos En Un Hospital de Segundo Nivel

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    Intraventricular hemorrhage (HIV) is a complication in neonates. It originates in the subependymal germinal matrix. This area is irrigated by a network of poorly differentiated vessels without a basement membrane. Also, it is fragile and vulnerable to the hemodynamic instability of cerebral blood flow. It is an important risk factor for periventricular leukomalacia, ventriculomegaly, and hydrocephalus. These neurological pathologies can generate sequelae in the pediatric population such as cerebral palsy (CP). Objective: To identify the factors associated with HIV in neonates treated in the early intervention program of the hospital of specialties of the child and the woman of the Secretary of Health of the State of Querétaro (HENMSESEQ). Material and Methods: Through the review of the clinical files, the factors associated with HIV present in the children attended to in the HENMSESEQ early intervention service were observed in 2015. Cases of HIV were corroborated by means of transfontanel ultrasound, statistical analysis with measures of central tendency, and comparison of the medians of children diagnosed with HIV and without diagnosis. Results: A group of 69 infants attended to in the early intervention program was studied. Out of them, 65.2% (45) were women and 34.3% (24) were men. They had a gestational age of 34.19 ± 4.22 weeks, birth weight of 2116.09 ± 859.36 g, and height of 44.06 ± 6.02 cm. Their stay in the Neonatal Intensive Care Unit (NICU) for the sample was 11.88 ± 16.84 days and they were 8.65 ± 12.20 days with invasive mechanical ventilation. There were 25 cases of HIV diagnosed by  transfontanel ultrasound. Out of the 25 cases, 7 (10%) were HIV grade I, 14 (20%) II, 4 (5.7%) III, and no cases of grade IV were diagnosed. Using the Mann-Whitney U test, a difference was found between the groups of neonates diagnosed with HIV and without diagnosis in weeks of gestation, height, weight, APGAR, days of intubation, and days of stay in NICU

    Full blood count values as a predictor of poor outcome of pneumonia among HIV-infected patients

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    Background To evaluate the predictive value of analytical markers of full blood count that can be assessed in the emergency department for HIV infected patients, with community-acquired pneumonia (CAP). Methods Prospective 3-year study including all HIV-infected patients that went to our emergency department with respiratory clinical infection, more than 24-h earlier they were diagnosed with CAP and required admission. We assessed the different values of the first blood count performed on the patient as follows; total white blood cells (WBC), neutrophils, lymphocytes (LYM), basophils, eosinophils (EOS), red blood cells (RBC), hemoglobin, hematocrit, mean corpuscular volume, mean corpuscular hemoglobin concentration, mean corpuscular hemoglobin, red blood cell distribution width (RDW), platelets (PLT), mean platelet volume, and platelet distribution width (PDW). The primary outcome measure was 30-day mortality and the secondary, admission to an intensive care unit (ICU). The predictive power of the variables was determined by statistical calculation. Results One hundred sixty HIV-infected patients with pneumonia were identified. The mean age was 42 (11) years, 99 (62%) were male, 79 (49%) had ART. The main route of HIV transmission was through parenteral administration of drugs. Streptococcus pneumonia was the most frequently identified etiologic agent of CAP The univariate analysis showed that the values of PLT (p < 0.009), EOS (p < 0.033), RDW (p < 0.033) and PDW (p < 0.09) were predictor of mortality, but after the logistic regression analysis, no variable was shown as an independent predictor of mortality. On the other hand, higher RDW (OR = 1.2, 95% CI 1.1-1.4, p = 0.013) and a lower number of LYM (OR 2.2, 95% CI 1.1-2.2; p = 0.035) were revealed as independent predictors of admission to ICU. Conclusion Red blood cell distribution and lymphocytes were the most useful predictors of disease severity identifying HIV infected patients with CAP who required ICU admission. Electronic supplementary material The online version of this article (10.1186/s12879-018-3090-0) contains supplementary material, which is available to authorized users

    Invasive pulmonary aspergillosis in heart transplant recipients: Is mortality decreasing

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    Introduction: Infection remains a major complication among heart transplant (HT) recipients, causing approximately 20% of deaths in the first year after transplantation. In this population, Aspergillus spp. can have various clinical presentations including invasive pulmonary aspergillosis (IPA), with high mortality (53-78%). Objectives: To establish the characteristics of IPA infection in HT recipients and their outcomes in our center. Methods: Among 328 HTs performed in our center between 1998 and 2016, we identified five cases of IPA. Patient medical records were examined and clinical variables were extracted. Results: All cases were male, and mean age was 62 years. The most common indication for HT was non-ischemic dilated cardiomyopathy. Productive cough was reported as the main symptom. The radiological assessment was based on chest X-ray and chest computed tomography. The most commonly reported radiographic abnormality was multiple nodular opacities in both techniques. Bronchoscopy was performed in all patients and Aspergillus fumigatus was isolated in four cases on bronchoalveolar lavage culture. Treatment included amphotericin in four patients, subsequently changed to voriconazole in three, and posaconazole in one patient, with total treatment lasting an average of 12 months. Neutropenia was found in only one patient, renal failure was observed in two patients, and concurrent cytomegalovirus infection in three patients. All patients were alive after a mean follow-up of 18 months. Conclusions: IPA is a potentially lethal complication after HT. Early diagnosis and prompt initiation of aggressive treatment are the cornerstone of better survival

    Efficacy and safety of a booster dose of influenza vaccination in solid organ transplant recipients, TRANSGRIPE 1-2: study protocol for a multicenter, randomized, controlled clinical trial

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    BACKGROUND: Despite administration of annual influenza vaccination, influenza-associated complications in transplant recipients continue to be an important cause of hospitalization and death. Although influenza vaccination has been proven to be the most effective measure to reduce influenza infection after transplantation, transplant recipients are still vulnerable to influenza infections, with lower serological responses to vaccination compared to the general population. In order to assess the efficacy and safety of an alternative immunization scheme for solid organ transplant recipients, the TRANSGRIPE1-2 Study Group aimed to test a booster dose administration 5 weeks after the standard vaccination. The primary objective of this trial was to compare short-term and long-term neutralizing antibody immunogenicity of a booster dose of influenza vaccination to the standard single-dose immunization scheme. Secondary objectives included the evaluation of the efficacy and/or safety, cellular immune response, incidence of influenza infection, graft rejection, retransplant and mortality rates. METHODS/DESIGN: This phase III, randomized, controlled, open-label clinical trial was conducted between October 2012 and December 2013 in 12 Spanish public referral hospitals. Solid organ transplant recipients (liver, kidney, heart or lung), older than 16 years of age more than 30 days after transplantation were eligible to participate. Patients (N = 514) were stratified 1:1 by center, type of organ and time after transplantation and who either received the standard single dose (n = 257) or were treated according to a novel influenza vaccination schedule comprising the administration of a booster dose 5 weeks after standard vaccination (n = 254). Seroconversion rates were measured as a determinant of protection against influenza (main outcome). Efficacy and safety outcomes were followed until 1 year after influenza vaccination with assessment of short-term (0, 5, 10 and 15 weeks) and long-term (12 months) results. Intention-to-treat, per-protocol and safety analyses will be performed. DISCUSSION: This trial will increase knowledge about the safety and efficacy of a booster dose of influenza vaccine in solid organ transplant recipients. At the time the manuscript was submitted for publication, trial recruitment was closed with a total of 499 participants included during a 2-month period (within the seasonal influenza vaccination campaign). TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT01761435 (registered 13 December 2012). EudraCT Identifier: 2011-003243-21 (registered 4 July 2011)

    Comportamento alimentar durante o confinamento por COVID-19 (CoV-Eat Project): protocolo de um estudo transversal em países de língua espanhola

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    In December 2019, cases of pneumonia of unknown etiology emerged, which were later classified as severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). On March 11st, the pandemic by COVID-19 disease was declared, and since then it has been used transmission containment measures such as social distancing and confinement, measures with known effects as stressors that can influence eating behavior. Therefore, the aim of this research protocol is to identify eating behavior through dietary restriction, emotional feeding, and uncontrolled intake and to explore the factors associated with these adult behaviors during the COVID-19 pandemic in Spanish-speaking countries.En diciembre de 2019 surgieron casos de neumonía de etiología desconocida, que más tarde fueron clasificados como coronavirus del síndrome respiratorio agudo grave de tipo 2 (SARS-CoV-2). El 11 de marzo se declaró la pandemia por la enfermedad respiratoria coronavirus disease 2019 (COVID-19), por lo que se recurrió a medidas de contención de la transmisión, como el distanciamiento social y confinamiento, medidas con conocidos efectos estresores que pueden influir en la conducta alimentaria. Por ello, el objetivo de esta investigación es identificar la conducta alimentaria a través de la restricción dietética, alimentación emocional e ingesta incontrolada, y explorar los factores asociados con estas conductas en adultos durante el confinamiento por COVID-19 en países hispanohablantes.Em dezembro de 2019 surgiram casos de pneumonia de etiologia desconhecida, posteriormente classificados como coronavírus de síndrome respiratória aguda grave do tipo 2 (SARS-CoV-2). No dia 11 de março, foi declarada a pandemia pela doença respiratória coronavirus disease 2019 (COVID-19), por isto foram utilizadas medidas de contenção da transmissão, como o distanciamento social e o confinamento, medidas com conhecidos efeitos estressantes que podem influenciar o comportamento alimentar. Portanto, o objetivo desta pesquisa é identificar o comportamento alimentar por meio da restrição dietética, a alimentação emocional e a ingestão descontrolada, e explorar os fatores associados a esses comportamentos em adultos durante o confinamento por COVID-19 em países de língua espanhola

    Detection of cytomegalovirus drug resistance mutations in solid organ transplant recipients with suspected resistance

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    BACKGROUND: Current guidelines recommend that treatment of resistant cytomegalovirus (CMV) in solid organ transplant (SOT) recipients must be based on genotypic analysis. However, this recommendation is not systematically followed. OBJECTIVES: To assess the presence of mutations associated with CMV resistance in SOT recipients with suspected resistance, their associated risk factors and the clinical impact of resistance. STUDY DESIGN: Using Sanger sequencing we prospectively assessed the presence of resistance mutations in a nation-wide prospective study between September 2013-August 2015. RESULTS: Of 39 patients studied, 9 (23%) showed resistance mutations. All had one mutation in the UL 97 gene and two also had one mutation in the UL54 gene. Resistance mutations were more frequent in lung transplant recipients (44% p=0.0068) and in patients receiving prophylaxis >/=6 months (57% vs. 17%, p=0.0180). The mean time between transplantation and suspicion of resistance was longer in patients with mutations (239 vs. 100days, respectively, p=0.0046) as was the median treatment duration before suspicion (45 vs. 16days, p=0.0081). There were no significant differences according to the treatment strategies or the mean CMV load at the time of suspicion. Of note, resistance-associated mutations appeared in one patient during CMV prophylaxis and also in a seropositive organ recipient. Incomplete suppression of CMV was more frequent in patients with confirmed resistance. CONCLUSIONS: Our study confirms the need to assess CMV resistance mutations in any patient with criteria of suspected clinical resistance. Early confirmation of the presence of resistance mutations is essential to optimize the management of these patients

    Mucosa-associated lymphoid tissue lymphoma and concurrent adenocarcinoma of the prostate

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    Primary mucosa-associated lymphoid tissue (MALT) lymphoma of the prostate is a rare disease that characteristically follows an indolent course. It is believed that infection or chronic inflammation may be triggers for malignant transformation in the prostate, but it is of unknown etiology. Reports of MALT lymphomas of the prostate with other concurrent primary prostate cancers are even more limited. We present the unique case of a 67-year-old male with concurrent adenocarcinoma of the prostate and primary MALT lymphoma of the prostate. The patient was treated with standard therapy for prostate adenocarcinoma, which would also treat a primary MALT lymphoma. He has been disease-free for over one year for both his primary malignancies. This case confirms that MALT lymphoma can arise concurrently with adenocarcinoma of the prostate
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