Using NIR irradiation and magnetic bismuth ferrite microparticles to accelerate the removal of polystyrene microparticles from the drinking water.

Magnetic bismuth ferrite (BiFO) microparticles were employed for the first time for the removal of polystyrene (PS) nano/microplastics from the drinking water. BiFO is formed by porous agglomerates with sizes of 5-11 µm, while the PS nano/microparticles have sizes in the range of 70-11000 nm. X-ray diffraction studies demonstrated that the BiFO microparticles are composed of BiFeO3/Bi25FeO40 (the content of Bi25FeO40 is ≈ 8.6%). Drinking water was contaminated with PS nano/microparticles (1 g L-1) and BiFO microparticles were also added to the contaminated water. Later, the mixture of PS-particles + BiFO was irradiated with NIR light (980 nm). Consequently, PS nano/microparticles melted on the BiFO microparticles due to the excessive heating on their surface. At the same time, the NIR (near infrared) light generated oxidizing agents (∙OH and h+), which degraded the by-products formed during the photocatalytic degradation of PS nano/microparticles. Subsequently, the NIR irradiation was stopped, and a Neodymium magnet was utilized to separate the BiFO microparticles from the water. This last procedure also permitted the removal of PS nano/microparticles by physical adsorption. Zeta potential measurements demonstrated that the BiFO surface was positively charged, allowing the removal of the negatively charged PS nano/microparticles by electrostatic attraction. The combination of the photocatalytic process and the physical adsorption permitted a complete removal of PS nano/microparticles after only 90 min as well as a high mineralization of by-products (≈95.5% as confirmed by the total organic carbon measurements). We estimate that ≈23.6% of the PS nano/microparticles were eliminated by photocatalysis and the rest of PS particles (≈76.4%) by physical adsorption. An outstanding adsorption capacity of 195.5 mg g-1 was obtained after the magnetic separation of the BiFO microparticles from the water. Hence, the results of this research demonstrated that using photocatalysis + physical-adsorption is a feasible strategy to quickly remove microplastic contaminants from the water.

Húmero varo: corrección mediante osteotomía proximal valguizante con placa de osteosíntesis preconformada en edad infantil / Humerus varus: correction by proximal valgus osteotomy with precontourned plate fixation in children

La deformidad en varo del húmero proximal en la infancia es una enfermedad poco conocida debido a su baja incidencia de presentación. En los últimos años se ha progresado en el conocimiento de su posible etiología y fisiopatología de producción. Su etiología puede ser muy variada, tanto con causas traumáticas como no. También han sido bien definidos los criterios radiológicos de diagnóstico y la discapacidad funcional que produce. Sin embargo, existen pocos trabajos en la literatura sobre el tratamiento quirúrgico de esta deformidad en la infancia. En este artículo presentamos un caso tratado mediante osteotomía valguizante fijada con una placa de osteosíntesis preconformada maleolar externa (AU)

Varus deformity of the proximal humerus in children is a little known pathology due to its low incidence of presentation. Progress has been made in recent years in understanding the possible etiology and pathophysiological causes. Radiological criteria for diagnosis and functional impairment that occurs have also been defined. However, there are few reports in the literature about the surgical treatment of this deformity in children. In this paper we present a case of surgical treatment of this deformity by corrective osteotomy fixed with precontoured external maleolar plate osteosynthesis (AU)

[Humerus varus: correction by proximal valgus osteotomy with precontourned plate fixation in children]. / Húmero varo: corrección mediante osteotomía proximal valguizante con placa de osteosíntesis preconformada en edad infantil.

Varus deformity of the proximal humerus in children is a little known pathology due to its low incidence of presentation. Progress has been made in recent years in understanding the possible etiology and pathophysiological causes. Radiological criteria for diagnosis and functional impairment that occurs have also been defined. However, there are few reports in the literature about the surgical treatment of this deformity in children. In this paper we present a case of surgical treatment of this deformity by corrective osteotomy fixed with precontoured external maleolar plate osteosynthesis.

Epidemia de enfermedad renal crónica en Centroamérica / An epidemic of chronic kidney disease in Central America: an overview

En varios países de la región centroamericana la enfermedad renal crónica se ha convertido en la primera causa de muerte en hombres jóvenes trabajadores sin antecedentes de enfermedades cardiovasculares. La falta de acceso por parte de los pacientes a terapias de sustitución renal (diálisis y/o transplante) hace que en algunas comunidades con elevada carga de enfermedad, ésta esté teniendo un alto impacto social y económico. Este editorial describe esta epidemia, recoge por primera la limitada evidencia científica hasta la fecha, explora las posibles hipótesis causales y prioriza intervenciones de salud pública necesarias a la luz de los resultados(AU)

The epidemiology of clinically apparent HIV infection in Nicaragua.

The purpose of this study was to describe the epidemic of clinically apparent human immunodeficiency virus/acquired immunodeficiency syndrome (HIV/AIDS) infection in Nicaragua and to discuss the reasons why the number of HIV patients presenting to the public health care system is increasing compared with other Central American countries. From 1987 to 2004, 1,614 HIV-positive patients were officially reported to the Nicaraguan STI/HIV/AIDS national program. Urban areas along the west-central and eastern part of Nicaragua showed the highest prevalence of AIDS, with a maximum of 54.2/year per 100,000 inhabitants. Most of the infections (91%) were acquired sexually: 65% by heterosexual contacts and 26% by homosexual contacts. The highest rate of infection was found in men aged between 20 to 39 years, with a peak around 35 to 39 years (annual incidence of 125.6 new cases per 100,000 inhabitants), and in women aged 20 to 34 years old, with a peak around 20 to 24 years (annual incidence 46.6 per 100,000 inhabitants). The male to female ratio of infection was 3:1. The death rate was stable until the beginning of 1999, but increased sharply thereafter up to 2004, the year that highly active antiretroviral therapy (HAART) was introduced in Nicaragua. In 2005, we observed a further increase in the mortality. However, our data do not represent the magnitude of the HIV/AIDS epidemic as a whole, due to a lack of systemic surveillance. HIV/AIDS in Nicaragua is in a nascent stage and is concentrated in high-risk populations, such as utility workers, commercial sex workers, men who have sex with men, prisoners, street children, housewives and police and military forces. Education of the population is an urgent need to increase HIV/AIDS-related knowledge, change attitudes, and increase safer sex practice in the community.

Asymptomatic infection and risk factors for leptospirosis in Nicaragua.

As part of an investigation of a 1995 outbreak of leptospirosis in Nicaragua, a cross-sectional serologic survey was conducted in the town of El Sauce. Of 566 persons, 85 (15%) were positive for IgM anti-Leptospira antibodies, indicating recent leptospirosis infection. Asymptomatic leptospirosis infection was common, with only 25 (29.4%) of the 85 seropositive inhabitants reporting a febrile illness in the 2 months before the survey. Multivariable analysis revealed that having an indoor water source remained independently protective against leptospirosis. Gathering wood was independently associated with infection. These findings suggest that asymptomatic infection with Leptospira is common in endemic areas of Leptospira transmission. Improvement in water sanitation and behavioral modifications to reduce environmental exposure may reduce the risk of leptospirosis in endemic regions.

Clinical, epidemiologic, and virologic features of dengue in the 1998 epidemic in Nicaragua.

From July to December 1998, a hospital- and health center-based surveillance system for dengue was established at selected sites in Nicaragua to better define the epidemiology of this disease. Demographic and clinical information as well as clinical laboratory results were obtained, and virus isolation, reverse transcriptase-polymerase chain reaction, and serologic assays were performed. World Health Organization criteria were used to classify disease severity; however, a number of patients presented with signs of shock in the absence of thrombocytopenia or hemoconcentration. Therefore, a new category was designated as "dengue with signs associated with shock" (DSAS). Of 1,027 patients enrolled in the study, 614 (60%) were laboratory-confirmed as positive cases; of these, 268 (44%) were classified as dengue fever (DF); 267 (43%) as DF with hemorrhagic manifestations (DFHem); 40 (7%) as dengue hemorrhagic fever (DHF); 20 (3%) as dengue shock syndrome (DSS); and 17 (3%) as DSAS. Interestingly, secondary infection was not significantly correlated with DHF/DSS, in contrast to previous studies in Southeast Asia. DEN-3 was responsible for the majority of cases, with a minority due to DEN-2; both serotypes contributed to severe disease. As evidenced by the analysis of this epidemic, the epidemiology of dengue can differ according to geographic region and viral serotype.

Epidemic leptospirosis associated with pulmonary hemorrhage-Nicaragua, 1995.

In October 1995, epidemic "hemorrhagic fever," without jaundice or renal manifestations, was reported in rural Nicaragua following heavy flooding; 2259 residents were evaluated for nonmalarial febrile illnesses (cumulative incidence, 6.1%) and 15 (0.7%) died with pulmonary hemorrhage. A case-control study found that case-patients were more likely than controls to have ever walked in creeks (matched odds ratio [MOR], 15.0; 95% confidence interval [CI], 1.7-132.3), have household rodents (MOR, 10.4; 95% CI, 1.1-97.1), or own dogs with titers >/=400 to Leptospira species (MOR, 23.4; 95% CI, 3.6-infinity). Twenty-six of 51 case-patients had serologic or postmortem evidence of acute leptospirosis. Leptospira species were isolated from case-patients and potential animal reservoirs. This leptospirosis epidemic likely resulted from exposure to flood waters contaminated by urine from infected animals, particularly dogs. Leptospirosis should be included in the differential diagnosis for nonmalarial febrile illness, particularly during periods of flooding or when pulmonary hemorrhage occurs.