520 research outputs found

    Últimos retos en el tratamiento de la catarata congénita

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    La descripció de la cataracta congènita és una opacitat de la lent ocular que apareix en el part o durant la primera infància, és una malaltia rara i sovint desconeguda, però a excepció d'altres raons associades amb ella que inclouen: genètica, metabòlica, infeccions, ús de corticoesteroides, trauma, uveitis, així com anomalies oculars. L'objectiu d'aquest treball és investigar diversos articles sobre els últims reptes del tractament de la cataracta congènita i quins tipus d'enfocaments es poden utilitzar per curar-los i per a l'ambliopia que es produeix a causa de la cataracta. Per a concloure, malgrat l'avanç de les tècniques quirúrgiques per als nens molt millor del que ho va ser fa anys, així que els reptes com la mida de l'ull, l'edat, la selecció d'exàmens de l'OL, l'horari de cirurgia i les complicacions, així com la remodelació de la visió post-cirúrgica; encara existeixen, però sobretot la rehabilitació de la visió i el tractament amblòpic per a les condicions post-cirúrgiques, i per a aquests casos menors, han de ser seguits periòdicament.La descripción de la catarata congénita es una opacidad del cristalino que aparece en el parto o durante la primera infancia, es una enfermedad rara y muchas veces de causa desconocida, pero salvo por otras razones asociadas a ella que incluyen; genéticas, metabólicas, infecciones, uso de corticoides, traumatismos, uveítis, así como anomalías oculares. El objetivo de este trabajo es investigar varios artículos sobre los últimos desafíos del tratamiento de la catarata congénita y qué tipos de enfoques se pueden utilizar para curarlos y para la ambliopía que se produce debido a la catarata. Para concluir, a pesar del avance en las técnicas quirúrgicas para niños mucho mejor que hace años, los desafíos como el tamaño del ojo, la edad, la selección de exámenes de LIO, el cronograma de cirugía y las complicaciones, así como la rehabilitación de la visión posquirúrgica; aún existen, pero sobre todo la rehabilitación de la visión y el tratamiento ambliópico para condiciones post-quirúrgicas, y para aquellos casos menores, deben ser objeto de un seguimiento periódico.The description of congenital cataract is an opaqueness of eye lens that appears at childbirth or during early childhood, It is a rare disease and often unknown cause, but except for other reasons associated with it that include; genetic, metabolic, infections, corticosteroids usage, trauma, uveitis, as well as ocular anomalies. The goal of this work is to research various articles on the latest challenges of treating congenital cataract and what kinds of approaches can be used for curing them and for the amblyopia that is produced due to cataract. To conclude, in spite of the advancement in surgical techniques for children much better than it was years ago, so the challenges such as eye size, age, selection of IOL examinations, surgery schedule, and complications, as well as vision rehab post-surgical; still exist, but most of all the vision rehabilitation and amblyopic treatment for post-surgical conditions, and for those minor cases, they must be followed up periodically

    Magnetic core-shell nanoparticles for drug delivery by nebulization

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    BACKGROUND: Aerosolized therapeutics hold great potential for effective treatment of various diseases including lung cancer. In this context, there is an urgent need to develop novel nanocarriers suitable for drug delivery by nebulization. To address this need, we synthesized and characterized a biocompatible drug delivery vehicle following surface coating of Fe(3)O(4) magnetic nanoparticles (MNPs) with a polymer poly(lactic-co-glycolic acid) (PLGA). The polymeric shell of these engineered nanoparticles was loaded with a potential anti-cancer drug quercetin and their suitability for targeting lung cancer cells via nebulization was evaluated. RESULTS: Average particle size of the developed MNPs and PLGA-MNPs as measured by electron microscopy was 9.6 and 53.2 nm, whereas their hydrodynamic swelling as determined using dynamic light scattering was 54.3 nm and 293.4 nm respectively. Utilizing a series of standardized biological tests incorporating a cell-based automated image acquisition and analysis procedure in combination with real-time impedance sensing, we confirmed that the developed MNP-based nanocarrier system was biocompatible, as no cytotoxicity was observed when up to 100 μg/ml PLGA-MNP was applied to the cultured human lung epithelial cells. Moreover, the PLGA-MNP preparation was well-tolerated in vivo in mice when applied intranasally as measured by glutathione and IL-6 secretion assays after 1, 4, or 7 days post-treatment. To imitate aerosol formation for drug delivery to the lungs, we applied quercitin loaded PLGA-MNPs to the human lung carcinoma cell line A549 following a single round of nebulization. The drug-loaded PLGA-MNPs significantly reduced the number of viable A549 cells, which was comparable when applied either by nebulization or by direct pipetting. CONCLUSION: We have developed a magnetic core-shell nanoparticle-based nanocarrier system and evaluated the feasibility of its drug delivery capability via aerosol administration. This study has implications for targeted delivery of therapeutics and poorly soluble medicinal compounds via inhalation route

    Cranked Relativistic Hartree-Bogoliubov Theory: Superdeformed Bands in the A190A\sim 190 Region

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    Cranked Relativistic Hartree-Bogoliubov (CRHB) theory is presented as an extension of Relativistic Mean Field theory with pairing correlations to the rotating frame. Pairing correlations are taken into account by a finite range two-body force of Gogny type and approximate particle number projection is performed by Lipkin-Nogami method. This theory is applied to the description of yrast superdeformed rotational bands observed in even-even nuclei of the A190A\sim 190 mass region. Using the well established parameter sets NL1 for the Lagrangian and D1S for the pairing force one obtains a very successful description of data such as kinematic (J(1)J^{(1)}) and dynamic (J(2)J^{(2)}) moments of inertia without any adjustment of new parameters. Within the present experimental accuracy the calculated transition quadrupole moments QtQ_t agree reasonably well with the observed data.Comment: 6 pages including 4 PostScript figures, uses RevTex, revised version, Phys.Rev. C, Rapid Communications, in pres

    Optimization of nanostructured/nano sized rice husk ash preparation

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    تم تطوير إجراء لإنتاج رماد قشر الأرز.  وقد تم دراسة تأثير العوامل المؤثرة على إنتاجية وخصائص السيليكا غير المتبلورة وهذه العوامل هى الكمية الابتدائية لقشر الأرز و ظروف الاحتراق و التقليب . تم التوصل إلى أن أفضل كمية كانت 20 غراما في الدقيقة في صحن تبخر خزفي بحجم 125 مل يحترق لمدة ساعتين عند درجة حرارة 700 درجة مئوية ، مع تبريد على ثلاث فترات أثناء الاحتراق لإنتاج السليكا عند أقل فقد عند الاشتعال وقد وجد أيضا أن  فترات التبريد تلعب دوراَ هاماَ فى تباين حجم الهيكل النانوي وتوزيع شكل الجسيمات. بالاضافة إلى أنه لم يتم العثور على مراحل بلورية في رماد قشر الأرز في جميع الحالات.The objective of the study is developing a procedure for production and characterization of rice husk ash (RHA). The effects of rice husk (RH) amount, burning/cooling conditions combined with stirring on producing of RHA with amorphous silica, highest SiO2, lowest loss on ignition (LOI), uniform particle shape distribution and nano structured size have been studied. It is concluded that the best amount is 20 g RH in 125 ml evaporating dish Porcelain with burning for 2 h at temperature 700 °C combined with cooling three times during burning to produce RHA with amorphous silica, SiO2 90.78% and LOI 1.73%. On the other hand, cooling and stirring times affect the variation of nano structured size and particle shape distribution. However, no crystalline phases were found in RHA in all cases. Results proved that the Attritor ball mill was more suitable than vibration disk mill for pulverizing nano structured RHA with 50% of particle size (D50) lower than 45 mm and 99 % of particle size (D99) lower than 144 mm to nanosized RHA with D50 lower than 36 nm and D99 lower than 57 nm by grinding time 8.16 min to every 1 g RHA without changes in morphousity of silica

    Photocatalytic Nanolithography of Self-Assembled Monolayers and Proteins

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    Self-assembled monolayers of alkylthiolates on gold and alkylsilanes on silicon dioxide have been patterned photocatalytically on sub-100 nm length-scales using both apertured near-field and apertureless methods. Apertured lithography was carried out by means of an argon ion laser (364 nm) coupled to cantilever-type near-field probes with a thin film of titania deposited over the aperture. Apertureless lithography was carried out with a helium–cadmium laser (325 nm) to excite titanium-coated, contact-mode atomic force microscope (AFM) probes. This latter approach is readily implementable on any commercial AFM system. Photodegradation occurred in both cases through the localized photocatalytic degradation of the monolayer. For alkanethiols, degradation of one thiol exposed the bare substrate, enabling refunctionalization of the bare gold by a second, contrasting thiol. For alkylsilanes, degradation of the adsorbate molecule provided a facile means for protein patterning. Lines were written in a protein-resistant film formed by the adsorption of oligo(ethylene glycol)-functionalized trichlorosilanes on glass, leading to the formation of sub-100 nm adhesive, aldehyde-functionalized regions. These were derivatized with aminobutylnitrilotriacetic acid, and complexed with Ni2+, enabling the binding of histidine-labeled green fluorescent protein, which yielded bright fluorescence from 70-nm-wide lines that could be imaged clearly in a confocal microscope

    Surgical site infection after gastrointestinal surgery in high-income, middle-income, and low-income countries: a prospective, international, multicentre cohort study

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    Background: Surgical site infection (SSI) is one of the most common infections associated with health care, but its importance as a global health priority is not fully understood. We quantified the burden of SSI after gastrointestinal surgery in countries in all parts of the world. Methods: This international, prospective, multicentre cohort study included consecutive patients undergoing elective or emergency gastrointestinal resection within 2-week time periods at any health-care facility in any country. Countries with participating centres were stratified into high-income, middle-income, and low-income groups according to the UN's Human Development Index (HDI). Data variables from the GlobalSurg 1 study and other studies that have been found to affect the likelihood of SSI were entered into risk adjustment models. The primary outcome measure was the 30-day SSI incidence (defined by US Centers for Disease Control and Prevention criteria for superficial and deep incisional SSI). Relationships with explanatory variables were examined using Bayesian multilevel logistic regression models. This trial is registered with ClinicalTrials.gov, number NCT02662231. Findings: Between Jan 4, 2016, and July 31, 2016, 13 265 records were submitted for analysis. 12 539 patients from 343 hospitals in 66 countries were included. 7339 (58·5%) patient were from high-HDI countries (193 hospitals in 30 countries), 3918 (31·2%) patients were from middle-HDI countries (82 hospitals in 18 countries), and 1282 (10·2%) patients were from low-HDI countries (68 hospitals in 18 countries). In total, 1538 (12·3%) patients had SSI within 30 days of surgery. The incidence of SSI varied between countries with high (691 [9·4%] of 7339 patients), middle (549 [14·0%] of 3918 patients), and low (298 [23·2%] of 1282) HDI (p < 0·001). The highest SSI incidence in each HDI group was after dirty surgery (102 [17·8%] of 574 patients in high-HDI countries; 74 [31·4%] of 236 patients in middle-HDI countries; 72 [39·8%] of 181 patients in low-HDI countries). Following risk factor adjustment, patients in low-HDI countries were at greatest risk of SSI (adjusted odds ratio 1·60, 95% credible interval 1·05–2·37; p=0·030). 132 (21·6%) of 610 patients with an SSI and a microbiology culture result had an infection that was resistant to the prophylactic antibiotic used. Resistant infections were detected in 49 (16·6%) of 295 patients in high-HDI countries, in 37 (19·8%) of 187 patients in middle-HDI countries, and in 46 (35·9%) of 128 patients in low-HDI countries (p < 0·001). Interpretation: Countries with a low HDI carry a disproportionately greater burden of SSI than countries with a middle or high HDI and might have higher rates of antibiotic resistance. In view of WHO recommendations on SSI prevention that highlight the absence of high-quality interventional research, urgent, pragmatic, randomised trials based in LMICs are needed to assess measures aiming to reduce this preventable complication

    Human amylin proteotoxicity impairs protein biosynthesis, and alters major cellular signaling pathways in the heart, brain and liver of humanized diabetic rat model in vivo

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    Chronic hypersecretion of the 37 amino acid amylin is common in type 2 diabetics (T2D). Recent studies implicate human amylin aggregates cause proteotoxicity (cell death induced by misfolded proteins) in both the brain and the heart
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