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1.
Int Ophthalmol ; 44(1): 90, 2024 Feb 17.
Artículo en Inglés | MEDLINE | ID: mdl-38367098

RESUMEN

OBJECTIVE: Diabetic Retinopathy (DR) is a severe complication of diabetes that damages the retina and affects approximately 80% of patients with diabetes for 10 years or more. This condition primarily impacts young and productive individuals, resulting in significant long-term medical complications for patients and society. The early stages of diabetic retinopathy often advance without noticeable symptoms, resulting in delayed identification and intervention. Therefore, develop approaches employing transfer learning methodologies to enhance early detection capabilities, facilitating timely diagnosis and intervention to mitigate the progression of diabetic retinopathy. METHODS: This study introduces a transfer learning approach for detecting four stages of DR: No DR, Mild, Moderate, and Severe. The methods AlexNet, VGG16, ResNet50, Inception v3, and DenseNet121 are utilized and trained using the Kaggle DR dataset. RESULTS: To assess the efficiency of the suggested improved network, the Kaggle dataset is employed to analyze four performance metrics: Sensitivity, Precision, Accuracy, and F1 score. DenseNet121 demonstrated superior accuracy among the two models, outperforming other models, making it a suitable option for automatic DR sign detection. CONCLUSION: The integration of the DenseNet121 model shows great promise in transforming the timely identification and treatment of DR, resulting in enhanced patient results in the long run and alleviating the burden on society.


Asunto(s)
Diabetes Mellitus , Retinopatía Diabética , Humanos , Retinopatía Diabética/complicaciones , Retina , Diagnóstico Precoz , Inteligencia Artificial
2.
Cell Mol Biol (Noisy-le-grand) ; 69(5): 150-155, 2023 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-37571884

RESUMEN

A concoction of unhealthy eating, inactivity, and the adverse effects of specific drugs brings on obesity. The primary cause of Obesity is the storage of too much energy and triglycerides in adipocytes, particularly white adipose tissue (WAT). In addition to modifying one's lifestyle, anti-obesity medicines are increasingly used as adjuvant therapy. Flavonoids are the major class of compounds having significant biological impacts and health-improving properties. To find novel flavonoid compounds that fight obesity using computational drug design techniques. This work targets 1DI protein to predict new flavonoid compounds that fight obesity. The study uses computational approaches to anticipate potential anti-obesity/inflammatory flavonoid compounds against obesity to prevent WAT differentiation by targeting ID-1, a DNA-binding protein inhibitor. Our study led to the identification of the protein target inhibitor lead CID: 5280443, which was found to be a potent inhibitor of the receptor. According to the findings of this study, this bio-active molecule may be used as a lead for the development of drugs that preferentially fight obesity without interfering with the functions of the human proteasome. The scientific community will benefit from these discoveries, which could aid in the creation of new medications that treat obesity more successfully.


Asunto(s)
Fármacos Antiobesidad , Proteínas de Unión al ADN , Humanos , Proteínas de Unión al ADN/metabolismo , Obesidad/tratamiento farmacológico , Obesidad/metabolismo , Tejido Adiposo Blanco/metabolismo , Fármacos Antiobesidad/farmacología , Fármacos Antiobesidad/uso terapéutico , Adipocitos , Tejido Adiposo Pardo/metabolismo
3.
Phys Chem Chem Phys ; 25(39): 26894-26905, 2023 Oct 11.
Artículo en Inglés | MEDLINE | ID: mdl-37782629

RESUMEN

Heliobacteria are anoxygenic phototrophs that have a Type I homodimeric reaction center containing bacteriochlorophyll g (BChl g). Previous experimental studies have shown that in the presence of light and dioxygen, BChl g is converted into 81-OH-chlorophyll aF (hereafter Chl aF), with an accompanying loss of light-driven charge separation. These studies suggest that the reaction center only loses the ability to transfer electrons once both BChl g' molecules of the P800 special pair have been converted to Chl aF'. The present work confirms that the partially converted BChl g'/Chl aF' special pair remains functional in samples exposed to dioxygen by demonstrating its presence using hyperfine couplings obtained from Q-band 1H ENDOR, 2D 14N HYSCORE and DFT methods. The DFT calculations of the BChl g'/BChl g' homodimeric primary donor, which are based on the recently published X-ray crystal structure, predict that the unpaired electron spin is equally delocalized over both BChl g' molecules and provide an excellent match to the experimental hyperfine couplings of the anaerobic samples. Exposure to dioxygen leads to substantial changes in the hyperfine interactions, indicative of greater localization of the unpaired electron spin. The measured hyperfine couplings are reproduced in the DFT calculations by replacing one of the BChl g' molecules of the primary donor with a Chl aF' molecule. The calculations reveal that the spin density becomes localized on BChl g' in the heterodimeric primary donor. Time-dependent DFT calculations demonstrate that conversion of either or both of the accessory BChl g molecules and/or one of the BChl g' molecules of P800 to Chl aF' results in minor effects on the energy of the charge-separated states. In contrast, if both of the BChl g' molecules of P800 are converted a large increase in the energy of the charge-separated state occurs. This suggests that the reaction center remains functional when only one half of the dimer is converted, however, conversion of both halves of the P800 dimer leads to loss of function.


Asunto(s)
Bacterioclorofila A , Bacterioclorofilas , Clorofila A , Bacterioclorofilas/química , Espectroscopía de Resonancia por Spin del Electrón
4.
Crit Care Med ; 50(9): 1339-1347, 2022 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-35452010

RESUMEN

OBJECTIVES: To determine the impact of a machine learning early warning risk score, electronic Cardiac Arrest Risk Triage (eCART), on mortality for elevated-risk adult inpatients. DESIGN: A pragmatic pre- and post-intervention study conducted over the same 10-month period in 2 consecutive years. SETTING: Four-hospital community-academic health system. PATIENTS: All adult patients admitted to a medical-surgical ward. INTERVENTIONS: During the baseline period, clinicians were blinded to eCART scores. During the intervention period, scores were presented to providers. Scores greater than or equal to 95th percentile were designated high risk prompting a physician assessment for ICU admission. Scores between the 89th and 95th percentiles were designated intermediate risk, triggering a nurse-directed workflow that included measuring vital signs every 2 hours and contacting a physician to review the treatment plan. MEASUREMENTS AND MAIN RESULTS: The primary outcome was all-cause inhospital mortality. Secondary measures included vital sign assessment within 2 hours, ICU transfer rate, and time to ICU transfer. A total of 60,261 patients were admitted during the study period, of which 6,681 (11.1%) met inclusion criteria (baseline period n = 3,191, intervention period n = 3,490). The intervention period was associated with a significant decrease in hospital mortality for the main cohort (8.8% vs 13.9%; p < 0.0001; adjusted odds ratio [OR], 0.60 [95% CI, 0.52-0.71]). A significant decrease in mortality was also seen for the average-risk cohort not subject to the intervention (0.49% vs 0.26%; p < 0.05; adjusted OR, 0.53 [95% CI, 0.41-0.74]). In subgroup analysis, the benefit was seen in both high- (17.9% vs 23.9%; p = 0.001) and intermediate-risk (2.0% vs 4.0 %; p = 0.005) patients. The intervention period was also associated with a significant increase in ICU transfers, decrease in time to ICU transfer, and increase in vital sign reassessment within 2 hours. CONCLUSIONS: Implementation of a machine learning early warning score-driven protocol was associated with reduced inhospital mortality, likely driven by earlier and more frequent ICU transfer.


Asunto(s)
Puntuación de Alerta Temprana , Paro Cardíaco , Adulto , Paro Cardíaco/diagnóstico , Paro Cardíaco/terapia , Mortalidad Hospitalaria , Humanos , Unidades de Cuidados Intensivos , Aprendizaje Automático , Signos Vitales
5.
Faraday Discuss ; 234(0): 195-213, 2022 05 18.
Artículo en Inglés | MEDLINE | ID: mdl-35147155

RESUMEN

The solar water-splitting protein complex, photosystem II (PSII), catalyzes one of the most energetically demanding reactions in nature by using light energy to drive a catalyst capable of oxidizing water. The water oxidation reaction is catalyzed at the Mn4Ca-oxo cluster in the oxygen-evolving complex (OEC), which cycles through five light-driven S-state intermediates (S0-S4). A detailed mechanism of the reaction remains elusive as it requires knowledge of the delivery and binding of substrate water in the higher S-state intermediates. In this study, we use two-dimensional (2D) hyperfine sublevel correlation spectroscopy, in conjunction with quantum mechanics/molecular mechanics (QM/MM) and density functional theory (DFT), to probe the binding of the substrate analog, methanol, in the S2 state of the D1-N87A variant of PSII from Synechocystis sp. PCC 6803. The results indicate that the size and specificity of the "narrow" channel is altered in D1-N87A PSII, allowing for the binding of deprotonated 13C-labeled methanol at the Mn4(IV) ion of the catalytic cluster in the S2 state. This has important implications on the mechanistic models for water oxidation in PSII.


Asunto(s)
Complejo de Proteína del Fotosistema II , Synechocystis , Metanol/metabolismo , Oxidación-Reducción , Oxígeno/química , Complejo de Proteína del Fotosistema II/química , Synechocystis/química , Synechocystis/genética , Synechocystis/metabolismo , Agua/química
6.
Proc Natl Acad Sci U S A ; 116(24): 11630-11639, 2019 06 11.
Artículo en Inglés | MEDLINE | ID: mdl-31142656

RESUMEN

A major challenge to the implementation of artificial photosynthesis (AP), in which fuels are produced from abundant materials (water and carbon dioxide) in an electrochemical cell through the action of sunlight, is the discovery of active, inexpensive, safe, and stable catalysts for the oxygen evolution reaction (OER). Multimetallic molecular catalysts, inspired by the natural photosynthetic enzyme, can provide important guidance for catalyst design, but the necessary mechanistic understanding has been elusive. In particular, fundamental transformations for reactive intermediates are difficult to observe, and well-defined molecular models of such species are highly prone to decomposition by intermolecular aggregation. Here, we present a general strategy for stabilization of the molecular cobalt-oxo cubane core (Co4O4) by immobilizing it as part of metal-organic frameworks, thus preventing intermolecular pathways of catalyst decomposition. These materials retain the OER activity and mechanism of the molecular Co4O4 analog yet demonstrate unprecedented long-term stability at pH 14. The organic linkers of the framework allow for chemical fine-tuning of activity and stability and, perhaps most importantly, provide "matrix isolation" that allows for observation and stabilization of intermediates in the water-splitting pathway.

7.
J Card Surg ; 37(11): 3813-3824, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36116113

RESUMEN

BACKGROUND AND AIM: We assessed the anatomical variations in coronary arterial patterns relative to the techniques of reimplantation in the setting of the arterial switch operation, relating the variations to influences on outcomes. METHODS: We reviewed pertinent published investigations, assessing events reported following varied surgical techniques for reimplantation of the coronary arteries in the setting of the arterial switch procedure. RESULTS: The prevalence of reported adverse events, subsequent to reimplantation, varied from 2% to 11%, with a bimodal presentation of high early and low late incidence. The intramural pattern continues to contribute to mortality, with some reports of 28% fatality. The presence of abnormal course relative to the arterial pedicles in the setting of single sinus origin was associated with a three-fold increase in mortality. Abnormal looping with bisinusal origin of arteries was not associated with increased risk. CONCLUSION: The techniques of transfer of the coronary arteries can be individually adapted to cater for the anatomical variations. Cardiac surgeons, therefore, need to be familiar with the myriad creative options available to achieve successful repair when there is challenging anatomy. Long-term follow-up will be required to affirm the superiority of any specific individual technique. Detailed multiplanar computed-tomographic scanning can now reveal all the variants, and elucidate the mechanisms of late complications. Coronary angioplasty or surgical revascularization may be considered in selected cases subsequent to the switch procedure.


Asunto(s)
Operación de Switch Arterial , Anomalías de los Vasos Coronarios , Transposición de los Grandes Vasos , Anomalías de los Vasos Coronarios/complicaciones , Anomalías de los Vasos Coronarios/cirugía , Vasos Coronarios/diagnóstico por imagen , Vasos Coronarios/cirugía , Humanos , Reimplantación , Transposición de los Grandes Vasos/complicaciones , Transposición de los Grandes Vasos/cirugía
8.
J Card Surg ; 37(5): 1353-1360, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35146794

RESUMEN

BACKGROUND: Over the course of time, new developments associated with the embryogenesis of the murine heart have served to clarify the developmental processes observed in the human heart. This evidence allows for the creation of a developmental framework for many congenital cardiac defects. AIMS: We aim to solidify the framework related to the categorization of both solitary and multiple ventricular septal defects. MATERIALS AND METHODS: Mice having genetic perturbation of the Furin enzyme have demonstrated perimembranous and juxta-arterial ventricular septal defects, permitting the inference to be made that these defects can co-exist with defects occurring within the apical muscular septum. RESULTS: Basis of developmental evidence, furthermore, all interventricular communications can be placed into one of three groups, namely those which are perimembranous, juxta-arterial, and muscular. All of the defects are described based on their borders as seen from the morphologically right ventricle. Our focus here will be on those defects within the muscular ventricular septum, recognizing that such defects can co-exist with those that are perimembranous. We discuss the differentiation of multiple discrete defects from those referred to as the "Swiss cheese" variant. CONCLUSIONS: As we show, appropriate surgical management requires an understanding of the specific terminology, as the surgical approach may differ depending on the combination of the individual defects. Data from the Society for Thoracic Surgeons revealed that both mortality and morbidity were increased in the setting of multiple as opposed to solitary ventricular septal defects.


Asunto(s)
Cardiopatías Congénitas , Defectos del Tabique Interventricular , Tabique Interventricular , Animales , Defectos del Tabique Interventricular/diagnóstico por imagen , Defectos del Tabique Interventricular/cirugía , Ventrículos Cardíacos , Humanos , Ratones
9.
J Card Surg ; 37(5): 1361-1376, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35146802

RESUMEN

BACKGROUND AND AIM: We showed in our anatomical review, ventricular septal defects existing as multiple entities can be considered in terms of three major subsets. We address here the diagnostic challenges, associated anomalies, the role and techniques of surgical instead of interventional closure, and the outcomes, including reinterventions, for each subset. METHODS: We reviewed 80 published investigations, noting radiographic findings, and the results of clinical imaging elucidating the location, number, size of septal defects, associated anomalies, and the effect of severe pulmonary hypertension. RESULTS: Overall, perioperative mortality for treatment of residual multiple defects has been cited to be between 0% and 14.2%, with morbidity estimated between 6% and 13%. Perioperative mortality is twice as high for perimembranous compared to muscular defects, with the need for reoperation being over four times higher. Perventricular hybrid approaches are useful for the closure of high anterior or apical defects. Overall, the results have been unsatisfactory. Pooled data reveals incidences between 2.8% and 45% for device-related adverse events. Currently, however, outcomes cannot be assessed on the basis of the different anatomical subsets. CONCLUSIONS: We have addressed the approaches, and the results, of therapeutic treatment in terms of coexisting discrete defects, the Swiss-cheese septum, and the arrangement in which a solitary apical muscular defect gives the impression of multiple defects when viewed from the right ventricular aspect. Treatment should vary according to the specific combination of defects.


Asunto(s)
Procedimientos Quirúrgicos Cardíacos , Defectos del Tabique Interventricular , Hipertensión Pulmonar , Dispositivo Oclusor Septal , Procedimientos Quirúrgicos Cardíacos/métodos , Defectos del Tabique Interventricular/diagnóstico por imagen , Defectos del Tabique Interventricular/cirugía , Ventrículos Cardíacos/cirugía , Humanos , Hipertensión Pulmonar/etiología , Lactante , Reoperación , Resultado del Tratamiento
10.
J Card Surg ; 37(5): 1340-1352, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35122446

RESUMEN

BACKGROUND AND AIM: On the basis of previously published accounts, coupled with our own experience, we have assessed the surgical approaches to patients with isomeric atrial appendages. METHODS: We reviewed pertinent published studies on surgical treatment of individuals with isomeric atrial appendages, with the pertinent surgical details provided by most of the manuscripts. RESULTS: Half of patients with right isomerism, and two-thirds of those with left isomerism have bilateral superior caval veins. Azygos extension of the inferior caval vein is reported in three-quarters of those with left isomerism. The coronary sinus is universally absent in right isomerism, along with totally anomalous pulmonary venous connection, and is absent in two-fifths of those with left isomerism. Univentricular atrioventricular connections are expected in up to three-quarters of those with right isomerism. Atrioventricular septal defect is reported in up to four-fifths, more frequently in right isomerism, with such patients typically having discordant ventriculoatrial connections or double outlet right ventricle. Reported mortalities extend to 85% for those with right, and 50% for those with left isomerism. In right isomerism, mortality is up to 54% for systemic-to-pulmonary arterial shunting, up to 75% for univentricular repair, and up to 95% for repair of totally anomalous pulmonary venous connection itself. No more than one-quarter had undergone Fontan completion, with reported mortalities of 21%. CONCLUSION: Early surgical results are satisfactory in patients with left isomerism, but disappointing for those with right. Recent advances in cardiac and liver transplantation may offer improved survival.


Asunto(s)
Apéndice Atrial , Síndrome de Heterotaxia , Venas Pulmonares , Apéndice Atrial/cirugía , Síndrome de Heterotaxia/cirugía , Humanos , Isomerismo , Venas Pulmonares/anomalías , Vena Cava Superior/anomalías
11.
J Am Chem Soc ; 143(22): 8324-8332, 2021 06 09.
Artículo en Inglés | MEDLINE | ID: mdl-34029102

RESUMEN

We address the protonation state of the water-derived ligands in the oxygen-evolving complex (OEC) of photosystem II (PSII), prepared in the S2 state of the Kok cycle. We perform quantum mechanics/molecular mechanics calculations of isotropic proton hyperfine coupling constants, with direct comparisons to experimental data from two-dimensional hyperfine sublevel correlation (HYSCORE) spectroscopy and extended X-ray absorption fine structure (EXAFS). We find a low-barrier hydrogen bond with significant delocalization of the proton shared by the water-derived ligand, W1, and the aspartic acid residue D1-D61 of the D1 polypeptide. The lowering of the zero-point energy of a shared proton due to quantum delocalization precludes its release to the lumen during the S1→ S2 transition. Retention of the proton facilitates the shuttling of a proton during the isomerization of the tetranuclear manganese-calcium-oxo (Mn4Ca-oxo) cluster, from the "open" to "closed" conformation, a step suggested to be necessary for oxygen evolution from previous studies. Our findings suggest that quantum-delocalized protons, stabilized by low-barrier hydrogen bonds in model catalytic systems, can facilitate the accumulation of multiple oxidizing equivalents at low overpotentials.

12.
J Am Chem Soc ; 143(18): 7135-7143, 2021 05 12.
Artículo en Inglés | MEDLINE | ID: mdl-33877827

RESUMEN

A dicopper nitrenoid complex was prepared by formal oxidative addition of the nitrenoid fragment to a dicopper(I) center by reaction with the iminoiodinane PhINTs (Ts = tosylate). This nitrenoid complex, (DPFN)Cu2(µ-NTs)[NTf2]2 (DPFN = 2,7-bis(fluorodi(2-pyridyl)methyl)-1,8-naphthyridine), is a powerful H atom abstractor that reacts with a range of strong C-H bonds to form a mixed-valence Cu(I)/Cu(II) µ-NHTs amido complex in the first example of a clean H atom transfer to a dicopper nitrenoid core. In line with this reactivity, DFT calculations reveal that the nitrenoid is best described as an iminyl (NR radical anion) complex. The nitrenoid was trapped by the addition of water to form a mixed-donor hydroxo/amido dicopper(II) complex, which was independently obtained by reaction of a Cu2(µ-OH)2 complex with an amine through a protonolysis pathway. This mixed-donor complex is an analogue for the proposed intermediate in copper-catalyzed Chan-Evans-Lam coupling, which proceeds via C-X (X = N or O) bond formation. Treatment of the dicopper(II) mixed donor complex with MgPh2(THF)2 resulted in generation of a mixture that includes both phenol and a previously reported dicopper(I) bridging phenyl complex, illustrating that both reduction of dicopper(II) to dicopper(I) and concomitant C-X bond formation are feasible.


Asunto(s)
Complejos de Coordinación/química , Cobre/química , Iminas/química , Complejos de Coordinación/síntesis química , Electrones , Modelos Moleculares , Estructura Molecular , Oxidación-Reducción
13.
Clin Exp Dermatol ; 46(8): 1482-1487, 2021 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-34081805

RESUMEN

BACKGROUND: Acute cutaneous graft-versus-host disease (acGVHD) following haematopoietic stem cell transplant (HSCT) is common but difficult to distinguish from other causes of rash. Plasma elafin has been proposed as a diagnostic and prognostic biomarker of skin GVHD. AIM: To evaluate the role of plasma elafin as a biomarker in acGVHD in an Indian population. METHODS: Plasma elafin was evaluated in a prospective study of HSCT recipients, conducted over 2 years, taking measurements at baseline and at onset of skin rash after HSCT. Patients were categorized into those with GVHD rash, those with non-GVHD rash and those with no rash and the three groups were compared. RESULTS: Two hundred and sixty-one patients with a median age of 16 years (range 1-61 years) and a male predominance (175 : 86 M/F) underwent HSCT during the study period: 56 patients in the GVHD group, 49 in the non-GVHD group and 156 in the no-rash group. The median baseline elafin was similar in all three groups. At the onset of rash, median elafin level was similar between GVHD and non-GVHD rash (34 549 vs. 32 077 pg/mL; P = 0.58) and between GVHD and no rash (34 549 vs. 26 197 pg/mL; P = 0.08). A rise in elafin from baseline was significantly different between GVHD and no rash (P < 0.001) but not between GVHD and non-GVHD rash (P = 0.44). CONCLUSION: The utility of plasma elafin as a biomarker of skin GVHD is very limited. Plasma elafin, although elevated in cutaneous GVHD, is not helpful in distinguishing between GVHD rash and other causes of rash following HSCT.


Asunto(s)
Elafina/sangre , Enfermedad Injerto contra Huésped/diagnóstico , Trasplante de Células Madre Hematopoyéticas/efectos adversos , Adolescente , Adulto , Biomarcadores/sangre , Niño , Preescolar , Diagnóstico Diferencial , Exantema/diagnóstico , Exantema/etiología , Femenino , Enfermedad Injerto contra Huésped/sangre , Humanos , Lactante , Masculino , Persona de Mediana Edad , Adulto Joven
14.
Optom Vis Sci ; 98(1): 81-87, 2021 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-33394935

RESUMEN

SIGNIFICANCE: A differential outcome in randomized controlled trials of anti-vascular endothelial growth factor (anti-VEGF) therapy, including ranibizumab, for diabetic macular edema is a major dilemma for planning, optimizing, and managing clinical usage. The variable outcome of the therapeutics necessitates the importance of finding a predictive biomarker for anti-VEGF therapy to improve subject selection. PURPOSE: Our study correlates the baseline pro- and anti-VEGF isoforms and its three receptors (VEGFReceptor1, VEGFReceptor2, and VEGFReceptor3) for circulatory candidate protein molecules among diabetic patients with macular edema, with the clinical outcome of ranibizumab therapy. METHODS: This study included 86 individuals who were anti-VEGF naive at the time of ascertainment but have completed the standardized therapy regimen of the clinic. Plasma proteins for pro- and anti-VEGF isoforms and its three receptors were determined in replicate by an enzyme-linked immunosorbent assay. RESULTS: The study demonstrated that 56 (65.12%) individuals benefited from the therapy in terms of letter gain (Snellen chart). Baseline plasma soluble VEGF receptor 2 (sVEGFR-2) was significantly higher among responders (65.10 pg/mL; 95% confidence interval, 55.41 to 74.80 pg/mL) compared with nonresponders (46.38 pg/mL; 95% confidence interval, 38.69 to 54.07 pg/mL; PFDR = .03). Diffuse diabetic macular edema with proliferative diabetic retinopathy increases the risk of nonresponse to the therapy by 3.03-fold (PFDR = .04). CONCLUSIONS: The present study postulates that diffuse diabetic macular edema with proliferative diabetic retinopathy and baseline circulatory soluble VEGF receptor 2 may be potential candidates as therapy-stratifying markers for ranibizumab treatment among patients with diabetic macular edema.


Asunto(s)
Inhibidores de la Angiogénesis/uso terapéutico , Biomarcadores/sangre , Diabetes Mellitus Tipo 2/tratamiento farmacológico , Retinopatía Diabética/tratamiento farmacológico , Edema Macular/tratamiento farmacológico , Ranibizumab/uso terapéutico , Diabetes Mellitus Tipo 2/sangre , Diabetes Mellitus Tipo 2/fisiopatología , Retinopatía Diabética/sangre , Retinopatía Diabética/fisiopatología , Ensayo de Inmunoadsorción Enzimática , Femenino , Humanos , Inyecciones Intravítreas , Edema Macular/sangre , Edema Macular/fisiopatología , Masculino , Persona de Mediana Edad , Factor A de Crecimiento Endotelial Vascular/antagonistas & inhibidores , Receptor 1 de Factores de Crecimiento Endotelial Vascular/sangre , Receptor 2 de Factores de Crecimiento Endotelial Vascular/sangre , Receptor 3 de Factores de Crecimiento Endotelial Vascular/sangre , Agudeza Visual/fisiología
15.
J Card Surg ; 36(10): 3770-3795, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34396590

RESUMEN

BACKGROUND AND AIM: We sought to address the varied anatomical details, the diagnostic challenges, associated cardiopulmonary anomalies, the techniques, and outcomes of management, including re-interventions of scimitar syndrome. METHODS: A total of 92 published investigations of scimitar syndrome were reviewed. Diagnostic information was provided by clinical presentations, radiographic findings, transthoracic and transesophageal echocardiography, computed-tomographic angiography, magnetic resonance imaging, angiocardiography, and ventilation/perfusion scans. These investigations served to elucidate the origin, course, and termination of the scimitar vein, the intracardiac anatomy, the presence of associated defects, and the patterns of any accompanying pulmonary lesions prior to surgical intervention. RESULTS: Of the patients described, up to four-fifths presented during infancy, with cardiac failure, increased pulmonary flow, and pulmonary hypertension. Associated cardiac and extracardiac defects, particularly hypoplasia of the right lung, are present in up to three-quarters of cases. Overall operative mortality has been cited between 4.8% and 5.9%. Mortality was highest in patients with preoperative pulmonary hypertension, and those undergoing surgery in infancy. Despite timely surgical intervention, post-repair obstruction of the scimitar vein, intra-atrial baffle obstruction, or stenosis of the inferior caval vein were reported in up to two-thirds of cases. The venous obstruction could not be related to any particular surgical technique. On long term follow-up, one sixth of patients reported persistent dyspnoea and recurrent respiratory infections. CONCLUSIONS: Any infants presenting with heart failure, right-sided heart, and hypoplastic right lung should be evaluated to exclude the syndrome. An increased appreciation of variables will contribute to improved surgical management.


Asunto(s)
Venas Pulmonares , Síndrome de Cimitarra , Angiografía por Tomografía Computarizada , Humanos , Lactante , Pulmón , Venas Pulmonares/diagnóstico por imagen , Venas Pulmonares/cirugía , Síndrome de Cimitarra/diagnóstico por imagen , Síndrome de Cimitarra/cirugía , Vena Cava Inferior
16.
J Card Surg ; 36(11): 4280-4291, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34392559

RESUMEN

BACKGROUND AND AIM: Although the retroaortic left brachiocephalic vein in isolation is of no clinical importance, its recognition in the setting of associated lesions is important. We sought to address issues concerning the influence of isomerism, the establishment of diagnosis, and its importance in various surgical and interventional procedures. METHODS: A total of 80 published clinical and necropsy studies in the setting of a retroaortic left brachiocephalic vein described 250 patients. Clinical presentation, radiographic, ultrasonographic findings, contrast echocardiography, computed-tomographic angiocardiography, magnetic resonance imaging, and angiocardiography provided the diagnostic information prior to considering the surgical approach to the associated cardiac anomalies. RESULTS: Among 250 reported cases, three-quarters had associated congenitally malformed hearts. Of these 189 patients, all but seven had usual atrial arrangement. Right isomerism was reported in five patients and two patients having left isomerism. Almost two-thirds had tetralogy of Fallot or its variants, over four-fifths had malformations involving the outflow tract, two-thirds had a right aortic arch with two patients having a cervical aortic arch, and onepatient had double aortic arch. Various innovative individualized surgical procedures were employed with an overall perioperative mortality of 3.4%. CONCLUSIONS: Although the retroaortic left brachiocephalic vein is asymptomatic, its recognition during clinical investigation should raise the possibility of an association with other malformations, especially right aortic arch, ventricular septal defect, and anomalies of the outflow tracts. We submit that an increased appreciation of this venous anomaly may facilitate surgical planning, endovascular procedures, placement of central venous lines, and transvenous pacemakers.


Asunto(s)
Defectos del Tabique Interventricular , Síndrome de Heterotaxia , Venas Braquiocefálicas/diagnóstico por imagen , Venas Braquiocefálicas/cirugía , Ecocardiografía , Humanos , Tomografía Computarizada por Rayos X
17.
J Card Surg ; 36(11): 4267-4279, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34392568

RESUMEN

BACKGROUND AND AIM: The morphological variations when one, or both, of the atrial chambers is subdivided, are many and varied. We sought to address clinical presentations, potentially misdiagnosed cases, diagnostic modalities, surgical approaches, and outcomes of this "family" of uncommon lesions. METHODS: A total of 193 published investigations were synthesized. Diagnostic information was provided by clinical presentation, and multimodality imaging studies. RESULTS: Almost three-quarters of patients with divided atrial chambers present during infancy with severe pulmonary hypertension and cardiac failure. Associated cardiac and extra-cardiac defects are present in between half and nine-tenths of cases. Acquired division of the left atrium has been reported after the Fontan operation, orthotopic cardiac transplantation, and complicated aortic valvar infective endocarditis. Surgery under cardiopulmonary bypass remains the definitive treatment. Balloon dilation may be considered in anatomically compatible variants in the setting of cardiac failure and pregnancy as a bridge todefinitive treatment. Overall, mortality has been cited between nil to 29%. Presentation during infancy, associated congenital anomalies, pulmonary hypertension, and surgery in the previous era, have been the reported causes of death. The operative survivors have long-term favourable outcomes, with near normal cardiac dimensions and low risk of recurrence. While asymptomatic patients with division of the right atrium do not need treatment, surgical resection of the dividing partition under cardiopulmonary bypass is recommended in symptomatic patients with complex anatomy, the spinnaker malformation, or associated cardiac anomalies. Balloon dilation may be considered in uncomplicated patients with less obstructive lesions. Hybrid intervention and endoscopic robotic correction also have been performed. CONCLUSIONS: Resection of the dividing shelf allows the survivors to regain near normal dimensions with a low risk of recurrence. We submit that an increased appreciation of the anatomic background to division of the atrial chambers will contribute to improved surgical management.


Asunto(s)
Corazón Triatrial , Procedimiento de Fontan , Cardiopatías Congénitas , Puente Cardiopulmonar , Atrios Cardíacos/diagnóstico por imagen , Atrios Cardíacos/cirugía , Humanos
18.
Phys Chem Chem Phys ; 22(11): 6457-6467, 2020 Mar 21.
Artículo en Inglés | MEDLINE | ID: mdl-32152610

RESUMEN

Chloracidobacterium (C.) thermophilum is a microaerophilic, chlorophototrophic species in the phylum Acidobacteria that uses homodimeric type-1 reaction centers (RC) to convert light energy into chemical energy using (bacterio)chlorophyll ((B)Chl) cofactors. Pigment analyses show that these RCs contain BChl aP, Chl aPD, and Zn2+-BChl aP' in the approximate ratio 7.1 : 5.4 : 1. However, the functional roles of these three different Chl species are not yet fully understood. It was recently demonstrated that Chl aPD is the primary electron acceptor. Because Zn2+-(B)Chl aP' is present at low abundance, it was suggested that the primary electron donor might be a dimer of Zn2+-BChl aP' molecules. In this study, we utilize isotopic enrichment and high-resolution two-dimensional (2D) 14N and 67Zn hyperfine sublevel correlation (HYSCORE) spectroscopy to demonstrate that the primary donor cation, P840+, in the C. thermophilum RC is indeed a Zn2+-BChl aP' dimer. Density functional theory (DFT) calculations and the measured electron-nuclear hyperfine parameters of P840+ indicate that the electron spin density on P840+ is distributed nearly symmetrically over two Zn2+-(B)Chl aP' molecules as expected in a homodimeric RC. To our knowledge this is the only example of a photochemical RC in which the Chl molecules of the primary donor are metallated differently than those of the antenna.


Asunto(s)
Acidobacteria/química , Bacterioclorofila A/química , Procesos Fotoquímicos , Zinc/química , Metabolismo Energético , Luz , Análisis Espectral
19.
Trop Anim Health Prod ; 52(4): 1739-1744, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-31898021

RESUMEN

The effect of supplementation of multiple enzymes at 0, 1X, and 2X concentration to the diet containing variable protein sources (replacement of soybean meal with 10% guar meal (GM), 10% rapeseed meal (RSM), and 10% cottonseed meal (CSM)) was studied in a factorial manner on performance, carcass yield, protein, and energy utilization in commercial broiler males. For this purpose, 600-day-old commercial male broiler chicks (Ross) were randomly divided into 12 treatment groups with 10 replications of 5 birds each and reared in battery brooders up to 42 days of age. Treatment groups are as follows: T1 control and T2 and T3 corn-soya diet with enzymes at 1X and 2X concentrations, respectively. From T4 to T12 treatments, corn-soya meal was replaced by 10% GM, RSM, and CSM without, with 1X and 2X concentration of enzyme supplementation, respectively. The cumulative body weight gain was significantly (P < 0.05) higher in control and birds fed with GM diet in pre-starter and starter as well as during overall period. Supplementation of multiple enzymes at 1X and 2X did not influence body weight, feed intake, and FCR (P > 0.05) during 0-42 days of age. During experimental period, birds fed with the control diet and 10% GM diet showed significantly (P < 0.05) higher cumulative feed intake and better FCR compared to birds fed with 10% RSM diet and 10% cottonseed meal (CSM). Supplementation of multiple enzymes did not influence the mortality and slaughter variables and protein utilization in broilers.


Asunto(s)
Alimentación Animal/análisis , Pollos , Dieta/veterinaria , Proteínas en la Dieta/administración & dosificación , Suplementos Dietéticos , Enzimas/administración & dosificación , Enzimas/farmacología , Fenómenos Fisiológicos Nutricionales de los Animales , Animales , Peso Corporal , Cyamopsis , Masculino , Nutrientes , Glycine max , Aumento de Peso , Zea mays
20.
Trop Anim Health Prod ; 52(5): 2297-2302, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32146684

RESUMEN

The experiment was conducted to study the effect of feeding diets with quality protein maize (QPM) along with cottonseed meal (CSM) and guar meal (GM) on nutrient utilization, body weight (BW) gain (BWG), feed efficiency, and antioxidant status in broiler chickens. The biological trial was conducted on day-old broiler chicks (n = 240), which were randomly distributed into 6 dietary groups having 8 replicates with 5 chicks. Six experimental diets were formulated to contain maize (diet I), QPM (diet II), maize+CSM80 g/kg + GM40 g/kg (diet III), maize + CSM120 g/kg + GM60 g/kg (diet IV), QPM+CSM80 g/kg + GM40 g/kg (diet V), and QPM+CSM120 g/kg + GM60g/kg (diet VI). The BWG and feed intake were recorded at weekly intervals. Supplementation of CSM and GM along with QPM or maize depressed (P < 0.05) BWG, feed conversion ratio, and slaughter variables in commercial broilers. Improvement of BWG and breast weight was recorded among the groups supplemented 80 g/kg CSM and 40 g/kg GM with a QPM-based diet compared with those groups fed 120 g/kg CSM and 60 g/kg GM with maize or QPM. The energy and protein utilization decreased among the groups supplemented CSM and GM. However, protein and energy utilization was increased (P < 0.05) among the groups fed QPM-based diets compared with those groups fed CSM and GM with maize or QPM. Therefore, it has been concluded that the performance and other parameters did not differ between the groups fed maize- and QPM-based diets in the present experiment. However, QPM with CSM and GM improved the performance, slaughter parameters, and nutrient utilization over CSM and GM with maize.


Asunto(s)
Alimentación Animal/análisis , Pollos , Dieta/veterinaria , Proteínas en la Dieta/análisis , Zea mays/química , Fenómenos Fisiológicos Nutricionales de los Animales , Animales , Peso Corporal , Cyamopsis , Proteínas en la Dieta/administración & dosificación , Suplementos Dietéticos , Masculino , Nutrientes , Aumento de Peso/efectos de los fármacos
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