[Iron in pre-operative stage and transfusion in patients undergoing hysterectomy]

<p>Abstract</p><p><strong>Background:</strong> The correction of preoperative anemia is part of the patient blood management program, in order to improve the patient's clinical results by reducing the number of transfusions in surgery. Uterine fibroids can cause anemia, so the application of iron before hysterectomy could reduce transfusion.</p><p><strong>Objective:</strong> To evaluate the impact of iron treatment in the preoperative stage on the need for transfusion in patients with anemia secondary to myomatosis in the trans and postoperative stage of hysterectomy.</p><p><strong>Material and methods:</strong> Patients with uterine myomatosis who presented with microcytic anemia in the preoperative stage were included; clinical records were reviewed, the clinical characteristics of the population were obtained; The patients were distributed into two study groups according to whether or not they had received iron treatment; the outcome variable was the transfusion of packed erythrocytes in the first 7 days after surgery</p><p><strong>Results:</strong> 134 patients were included, with a median fibroid size of 4 cm. 21 (15.6%) patients used iron. Patients who used iron had a relative risk (RR): 0.36 (95%CI: 0.12-1.07). Delta hemoglobin < 1 g/dL, RR: 1.59 (95%CI: 0.94-2.67). Uterine fibroid size > 5cm had a RR of 1.96 (95%CI: 1.25-3.05).</p><p><strong>Conclusion:</strong></p><p> Treatment with iron in the pre-surgical stage showed a tendency to protect transfusions in the trans and post-surgical stage. The main factor related to transfusion was fibroid size > 5 cm.</p><p><strong>Introducción</strong>: la corrección de la anemia preoperatoria parte del programa de manejo hemático del paciente, a fin de mejorar sus resultados clínicos disminuyendo la cantidad de transfusiones en cirugía. La miomatosis uterina puede cursar con anemia, por lo que la aplicación de hierro antes de la histerectomía podría disminuir la transfusión.</p><p><strong>Objetivo</strong>: evaluar el impacto del tratamiento con hierro en la etapa prequirúrgica sobre la necesidad de transfusión en pacientes con anemia secundaria a miomatosis en la etapa trans y posoperatoria de histerectomía.</p><p><strong>Material y métodos</strong>: se incluyeron pacientes con miomatosis uterina que cursaron con anemia microcítica en la etapa preoperatoria; se realizó revisión de los expedientes clínicos y se obtuvieron las características clínicas de la población. Las pacientes se distribuyeron en dos grupos de estudio de acuerdo con el antecedente de haber recibido o no tratamiento con hierro. La variable de desenlace fue la transfusión de concentrados eritrocitarios en los primeros siete días a partir de la cirugía.</p><p><strong>Resultados</strong>: se incluyeron 134 pacientes,  21 (15.6%) utilizaron hierro. Las pacientes que utilizaron hierro tuvieron un riesgo relativo (RR) de 0.36 (IC95%: 0.12-1.07) para transfusión. La delta de hemoglobina < 1 g/dL tuvo un RR: 1.59 (IC95%: 0.94-2.67). El tamaño de mioma > 5 cm tuvo un RR: 1.96 (IC95%: 1.25-3.05).</p><p><strong>Conclusión</strong>: el tratamiento con hierro en etapa prequirúrgica mostró tendencia a protección para transfusiones en etapa trans y posquirúrgica. El principal factor relacionado para transfusión fue el tamaño del mioma > 5 cm.</p&gt

Prevalence and risk factors of Occult Hepatitis C infections in blood donors from Mexico City.

BACKGROUND:The circulatory system is the main mechanism for transmission of the Hepatitis C Virus (HCV). A new class of HCV infections, Occult HCV infection (OCI), is defined as the presence of HCV-RNA in hepatocytes with the absence of HCV in the serum/plasma utilizing current laboratory assays. Different groups have reported the prevalence of OCI; however, its associated risk factors have not been established. In Mexico, there are no reports about OCI, so the objective of our study was to determine the prevalence of OCI in total blood donors in Mexico City, as well as its associated risk factors. METHODS:Blood donors that were considered eligible for donation, according to NOM 253-SSA1-2012, were randomly selected. Demographic data was collected from 1,037 donors. Plasma and peripheral blood mononuclear cells were assessed for HCV-RNA. The presence of HCV-RNA was determined by nested PCR for the 5'-UTR region. Logistic regression was used to calculate the odds ratio (OR) and 95% confidence interval (95%CI) to determine the level of association. RESULTS:The prevalence of OCI was 3.4% among blood donors. Homosexual relationships (OR = 5.52, 95%CI: 1.53-19.92, p<0.05) and acupuncture (OR = 3.56, 95%CI: 1.41-8.98, p<0.05) were significantly associated with OCI. CONCLUSION:There is a significant presence of OCI in the blood donor population in Mexico City. The main risk factors for OCI transmission are homosexual relationships and acupuncture. This study supports the increased use of sensitive and specific screening tests for blood bank testing

Challenges in the design of concentrator photovoltaic (CPV) modules to achieve highest efficiencies

Concentrator photovoltaics (CPV) is a special high efficiency system technology in the world of PV-technologies. The idea of CPV is to use optical light concentrators to increase the incident power on solar cells. The solar cell area is comparatively tiny, thus saving expensive semiconductor materials and allowing the use of more sophisticated and more costly multi-junction solar cells. The highest CPV module efficiency achieved is 38.9%. This CPV module uses four-junction III-Vbased solar cells. Moreover, mini-modules have already achieved an efficiency of 43.4%. The interaction between optics, cells, and layout of the module and tracker determines the overall field performance. Today, some utility scale CPV plants are installed. The CPV technology allows for many technical solutions for system designs and for optimizing performance while maintaining the economics. This paper will review the achievements and discuss the challenges for the CPV module technology and its components. We discuss the different components and the most important effects regarding the module design. Furthermore, we present the module designs that have shown the highest efficiencies