RESUMEN
Silver nanoparticles are one of the most extensively studied nanomaterials due to their high stability and low chemical reactivity in comparison to other metals. They are commonly synthesized using toxic chemical reducing agents which reduce metal ions into uncharged nanoparticles. However, in the last few decades, several efforts were made to develop green synthesis methods to avoid the use of hazardous materials. The natural biomolecules found in plants such as proteins/enzymes, amino acids, polysaccharides, alkaloids, alcoholic compounds, and vitamins are responsible for the formation of silver nanoparticles. The green synthesis of silver nanoparticles is an eco-friendly approach, which should be further explored for the potential of different plants to synthesize nanoparticles. In the present review we describe the green synthesis of nanoparticles using plants, bacteria, and fungi and the role of plant metabolites in the synthesis process. Moreover, the present review also describes some applications of silver nanoparticles in different aspects such as antimicrobial, biomedicine, mosquito control, environment and wastewater treatment, agricultural, food safety, and food packaging.
Asunto(s)
Nanopartículas del Metal , Plata , Tecnología Química Verde/métodos , Nanopartículas del Metal/química , Extractos Vegetales/química , Plantas/metabolismo , Plata/químicaRESUMEN
INTRODUCTION: In May 2010, lead poisoning (LP) was confirmed among children <5years (U5) in two communities in Zamfara state, northwest Nigeria. Following reports of increased childhood deaths in Bagega, another community in Zamfara, we conducted a survey to investigate the outbreak and recommend appropriate control measures. METHODS: We conducted a cross-sectional survey in Bagega community from 23rd August to 6th September, 2010. We administered structured questionnaires to parents of U5 to collect information on household participation in ore processing activities. We collected and analysed venous blood samples from 185 U5 with LeadCare II machine. Soil samples were analysed with X-ray fluorescence spectrometer for lead contamination. We defined blood lead levels (BLL) of >10ug/dL as elevated BLL, and BLL ≥45ug/dL as the criterion for chelation therapy. We defined soil lead levels (SLL) of ≥400 parts per million (ppm) as elevated SLL. RESULTS: The median age of U5 was 36 months (Inter-quartile range: 17-48 months). The median BLL was 71µg/dL (range: 8-332µg/dL). Of the 185 U5, 184 (99.5%) had elevated BLL, 169 (91.4%) met criterion for CT. The median SLL in tested households (n = 37) of U5 was 1,237ppm (range: 53-45,270ppm). Households breaking ore rocks within the compound were associated with convulsion related-children's death (OR: 5.80, 95% CI: 1.08 - 27.85). CONCLUSION: There was an LP outbreak in U5 in Bagega community possibly due to heavy contamination of the environment as a result of increased ore processing activities. Community-driven remediation activities are ongoing. We recommended support for sustained environmental remediation, health education, intensified surveillance, and case management.
Asunto(s)
Intoxicación por Plomo/epidemiología , Plomo/sangre , Minería , Preescolar , Estudios Transversales , Brotes de Enfermedades , Polvo , Exposición a Riesgos Ambientales , Composición Familiar , Oro , Encuestas Epidemiológicas , Humanos , Lactante , Intoxicación por Plomo/sangre , Intoxicación por Plomo/mortalidad , Tamizaje Masivo , Minería/legislación & jurisprudencia , Nigeria/epidemiología , Vigilancia de la Población , Factores de Riesgo , Convulsiones/inducido químicamente , Convulsiones/epidemiología , Suelo/químicaRESUMEN
BACKGROUND: Treatment and care for female genital fistula have become increasingly available over the last decade in countries across Africa and South Asia. Before the International Federation of Gynaecology and Obstetrics (FIGO) and partners published a global fistula training manual in 2011 there was no internationally recognized, standardized training curriculum, including perioperative care. The community of fistula care practitioners and advocates lacks data about the prevalence of various perioperative clinical procedures and practices and their potential programmatic implications are lacking. METHODS: Data presented here are from a prospective cohort study conducted between September 2007 and September 2010 at 11 fistula repair facilities supported by Fistula Care in five countries. Clinical procedures and practices used in the routine perioperative management of over 1300 women are described. RESULTS: More than two dozen clinical procedures and practices were tabulated. Some of them were commonly used at all sites (e.g., vaginal route of repair, 95.3% of cases); others were rare (e.g., flaps/grafts, 3.4%) or varied widely depending on site (e.g. for women with urinary fistula, the inter-quartile range for median duration of post-repair bladder catheterization was 14 to 29 days). CONCLUSIONS: These findings show a wide range of clinical procedures and practices with different program implications for safety, efficacy, and cost-effectiveness. The variability indicates the need for further research so as to strengthen the evidence base for fistula treatment in developing countries.