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2.
Biotechnol Rep (Amst) ; 30: e00609, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33898275

RESUMO

Living organisms are created by carbohydrate biopolymers such as chitosan, carboxymethyl cellulose, alginate and lignin. These carbohydrate biopolymers have been extensively used for environmental applications because they are bio-degradable, bio-compatible, non-toxic and inexpensive. Recently, carbohydrate biopolymers have been used to prepare different nanocomposite adsorbents for treatment of wastewater. These adsorbents explored the removal effectiveness of inorganic pollutants from aqueous solution. This review article discusses the synthesis and application of chitosan, carboxymethyl cellulose, alginate and lignin nanocomposites as adsorbents for heavy metals. Toxic metals can be efficiently absorbed by cross-linkers, distributed in aqueous solutions of divalent heavy metal ions to examine their polymer absorption capacity. These nanocomposites were used for the adsorption of highly toxic metals such as Cd2+, Pb2+ and Zn2+ in water. To make heavy metal ion uptake more effective, more functionalization has been implemented such as blending, grafting, or mixing with different nanomaterials with an extra functional group. The integration of the second part into the main polymer chain not only adds functionality but also increases mechanical efficiency, one of the core criteria for adsorbent recyclability. The remediation method of metal ions from wastewater is cheaper as long as the adsorbent is reused. Furthermore, they exhibited good performance for the reuse of spent adsorbents after adsorption-desorption processes including latent fingerprint detection with nanomaterials by using the powder dusting method. Chitosan, carboxymethyl cellulose, alginate and lignin based nanocomposites have demonstrated better adsorption activities due to great physical and chemical properties for the chelation of heavy metals such as Cd2+, Pb2+ and Zn2+ from water and also higher regeneration with various eluents after several desorption-adsorption cycles. In addition, reuse of the spent adsorbents in latent fingerprint detection with different nanomaterials is discussed. Finally, this review article makes recommendations for future studies in light of environmentally favourable and economical applications.

3.
HIV Med ; 19 Suppl 1: 52-57, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29488696

RESUMO

OBJECTIVES: The aims of this study were to to assess the feasibility of simultaneous testing for the blood-borne viruses (BBV), HIV, hepatitis C (HCV) and hepatitis B (HBV), in the Emergency Department (ED) and ascertain the seroprevalence for these three viruses in this setting. METHODS: A pilot BBV testing program was undertaken as part of routine clinical care in the ED. All ED attendees aged between 16 and 65 years old who were able to consent were tested over a 55 week period on an opt out basis. Patients with positive test results were linked to clinical services. Interventions aimed at improving testing rates were implemented and evaluated by quality improvement (QI) methodology. RESULTS: Of 25,520 age-eligible ED attendees, 6108 (24%) underwent BBV testing; an additional 1160 (4.5%) underwent a standalone HIV test (total of 7268 (28%) individuals).There were 83/7268 (1.1%) non-negative (ie reactive or equivocal) results for HIV and 103/6108 (1.7%) and 32/6108 (0.52%) for anti-HCV IgG and HBsAg, respectively. Of these, 12 (0.17%), 16 (0.26%) and 8 (0.13%) were new reactive tests for HIV, HCV and HBV, respectively, which were able to be confirmed on a second test. Specific QI interventions led to temporary increases in testing rates. CONCLUSIONS: An opt out BBV testing program in the ED is feasible and effective at finding new cases. However, the testing rate was low at 24%. Although QI interventions led to some improvement in testing rates, further studies are required to identify ways to achieve sustained increases in testing in this setting.


Assuntos
Serviços de Diagnóstico/organização & administração , Serviços Médicos de Emergência/métodos , Infecções por HIV/diagnóstico , Hepatite B/diagnóstico , Hepatite C/diagnóstico , Adolescente , Adulto , Idoso , Serviço Hospitalar de Emergência , Feminino , Infecções por HIV/epidemiologia , Hepatite B/epidemiologia , Hepatite C/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Estudos Soroepidemiológicos , Adulto Jovem
4.
Clin Genet ; 93(5): 1093-1096, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29318572

RESUMO

MPV17-related mitochondrial neurohepatopathy is a rare genetic disorder worldwide. We report on a novel pathogenic variant in the MPV17 gene in 24 unrelated neurohepatopathic infants of non-consanguineous Black South African heritage. Exome sequencing identified homozygosity for a c.106C>T nonsense variant in exon 3 of the human MPV17 gene in 2 unrelated index patients. mRNA analysis revealed transcripts both with and without exon 3, indicating both reduced splice efficiency and premature termination as mechanisms for disease. Carrier frequency in this population was found to be 1 in 68 (95% CI; 1/122-1/38) with an estimated newborn incidence of 1 in 18 496 (95% CI; 1/59 536-1/5776). Affected infants all presented with infantile onset neurohepatopathy with none surviving beyond infancy. This description of a relatively common pathogenic variant underlying a previously uncharacterized severe neurohepatopathy in South Africa will engender increased awareness, earlier diagnosis and possibly improve outcome if preventative or specific therapeutic options can be found.


Assuntos
Degeneração Hepatolenticular/genética , Proteínas de Membrana/genética , Mitocôndrias/genética , Doenças Mitocondriais/genética , Proteínas Mitocondriais/genética , Códon sem Sentido/genética , Feminino , Degeneração Hepatolenticular/patologia , Homozigoto , Humanos , Lactente , Masculino , Mitocôndrias/patologia , Doenças Mitocondriais/patologia , Sítios de Splice de RNA/genética , Splicing de RNA , África do Sul/epidemiologia
5.
S. Afr. j. child health (Online) ; 12(3): 100-104, 2018. tab
Artigo em Inglês | AIM (África) | ID: biblio-1270330

RESUMO

Background. Vitamin A deficiency (VAD) is a major public health problem that affects South African children and is a major contributor to the mortality of children under five years of age. VAD can result in visual impairment, diarrhoea and increased risk of severe measles and death. Orange-fleshed sweet potato (OFSP), a staple crop biofortified with provitamin A, has the potential to improve vitamin A intake in infants, especially when used as a complementary food.Objective. To assess the acceptance of an OFSP complementary food by infant caregivers.Methods. This study was conducted at the Newtown Community Health Centre, Inanda, in the eThekwini District of KwaZulu-Natal (KZN). Sixty-three infant caregivers assessed the acceptance of complementary foods made from OFSP and white-fleshed sweet potato (WFSP) (control), using a five-point hedonic rating test. In addition, ten caregivers participated in two focus group discussions, using pre-determined questions.Results. There were no statistically significant differences in the sensory attribute ratings of complementary foods made from WFSP and OFSP. The OFSP complementary food was well-accepted, especially its colour and soft texture. None of the focus group discussion participants had seen or tasted the OFSP before. Caregivers were willing to buy the OFSP, if it were available and cheaper than the WFSP.Conclusion. The complementary food made from the OFSP was highly acceptable to infant caregivers attending the Newtown Community Health Centre in KZN. It has the potential to be used in complementary feeding and to improve the vitamin A status of infants


Assuntos
Cuidadores , Fenômenos Fisiológicos da Nutrição do Lactente , Aceitação pelo Paciente de Cuidados de Saúde , Solanum tuberosum , África do Sul
6.
Osteoporos Int ; 27(1): 361-6, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26510846

RESUMO

UNLABELLED: Both men and women who sustain a fracture of the distal forearm run an increased risk of sustaining a subsequent hip fracture. Our study implies that these patients may not necessarily constitute a group in which osteoporosis screening is warranted. INTRODUCTION: People who sustain a distal radius fracture run an increased risk of sustaining a subsequent hip fracture. However, many institutions only screen for osteoporosis at the time of a hip fracture. We aimed to determine the true incidence of preceding distal radius fractures in an Asian population of patients with a hip fracture aged 60 years or older and whether screening for osteoporosis earlier would be beneficial. METHODS: We reviewed 22 parameters of 572 patients aged 60 years or older admitted after sustaining a hip fracture over a 3-year period. This included the occurrence or absence of a distal radius fracture in the 10 years preceding their hip fracture. RESULTS: Twenty-nine patients (5 %) had a fracture of the distal radius in the preceding decade. Univariate analyses suggested that hip fracture patients who had preceding distal radius fractures were older, female, have lower mean haemoglobin levels, and right-sided hip fractures. Of these factors, only age was found to have significant predictive value in a multivariate analysis. CONCLUSIONS: A number of institutions have started to screen for osteoporosis when a patient presents with a fracture of the distal radius because these patients may have an increased risk of a subsequent hip fracture. Our study implies that this may not be warranted. Implementing such a screening service from both cost and resource utilization point of view must be studied prospectively and in greater detail considering earlier screening may only be beneficial to a very small percentage of patients.


Assuntos
Fraturas do Quadril/etiologia , Osteoporose/diagnóstico , Fraturas por Osteoporose/diagnóstico , Fraturas do Rádio/etiologia , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Densidade Óssea/fisiologia , Feminino , Fraturas do Quadril/patologia , Fraturas do Quadril/fisiopatologia , Humanos , Masculino , Programas de Rastreamento/métodos , Pessoa de Meia-Idade , Osteoporose/complicações , Osteoporose/fisiopatologia , Fraturas por Osteoporose/patologia , Fraturas por Osteoporose/fisiopatologia , Fraturas do Rádio/fisiopatologia , Recidiva , Estudos Retrospectivos , Fatores de Risco , Fatores de Tempo
7.
J Pediatr Surg ; 50(11): 1874-9, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26265193

RESUMO

INTRODUCTION: Gastrointestinal sequelae of cytomegalovirus are rare, usually associated with significant immune compromise, and carry a high morbidity and mortality. Gastrointestinal disease frequently requires surgical intervention for diagnosis and management. AIM: The aim of the study is to evaluate the incidence, presentation and management of gastrointestinal cytomegalovirus disease in a pediatric population. METHOD: Between January 2003 and June 2011, a retrospective folder review was conducted of all symptomatic children with proven CMV disease, presenting to the surgical service. Eligible patients were identified using the surgical, histopathology and serology databases. RESULTS: Thirty-eight patients (1.8/1000 surgical admissions) were identified with a median presenting age of 5months (range 3days-12years). Esophagitis (n=18) and small bowel disease (n=16) predominated, but CMV was seen throughout the gastrointestinal tract. Risk factors included HIV infection (n=21, 55%) and recent gastrointestinal surgery or infection (n=10, 26%). Characteristic multiple jejunoileal perforations were seen in six patients. Compared to upper GIT disease, intestinal involvement was associated with younger age and doubled mortality. In HIV-infected children, median CD4 (%) was lower in intestinal compared to upper gastrointestinal disease. Morbidities included anastomotic breakdowns (5), anastomotic strictures (3), relook laparotomies (10), resistant esophageal strictures (5) and prolonged parenteral nutrition (5). Anti-CMV drugs were given in 63%. Overall mortality was 32% (12/38) and was associated with lower GIT disease. CONCLUSION: Invasive CMV gastrointestinal disease in our children was predominantly HIV-associated, or followed a major lower gastrointestinal inflammatory insult in infants younger than 6months. Successful therapy requires a high index of suspicion of active CMV disease to allow early implementation of CMV viral load control and aggressive treatment of the underlying immune impairment. Multiple surgical interventions are often required for both tissue diagnosis and management of acute and chronic complications. CMV-viral-load-tailored anti-CMV therapy is supported by recent literature.


Assuntos
Infecções por Citomegalovirus/complicações , Infecções por Citomegalovirus/terapia , Gastroenteropatias/terapia , Gastroenteropatias/virologia , Fatores Etários , Criança , Pré-Escolar , Auditoria Clínica , Citomegalovirus , Infecções por Citomegalovirus/epidemiologia , Procedimentos Cirúrgicos do Sistema Digestório , Feminino , Gastroenteropatias/epidemiologia , Infecções por HIV/complicações , Humanos , Incidência , Lactente , Recém-Nascido , Masculino , Estudos Retrospectivos , Fatores de Risco
8.
J Anim Physiol Anim Nutr (Berl) ; 99(2): 281-9, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25244110

RESUMO

Poultry diets are formulated with additional animal fat or vegetable oils to improve growth rate and feed conversion efficiency. High-fat diet feeding in rats and fish has been shown to result in alterations in the phospholipid composition and cholesterol content of the erythrocyte membrane, in turn affecting erythrocyte osmotic fragility. In contrast, the few studies performed using high-fat diet feeding in avian species show no changes in erythrocyte osmotic fragility. This study made use of the Japanese quail as no data exists on investigation of this species with respect to high-fat diet feeding and erythrocyte osmotic fragility. Fifty-seven male quail were randomly divided into six groups and fed either a standard diet (commercial poultry feed) or one of five high-fat diets (commercial poultry feed with 22% of either coconut oil, lard, palm oil, soya bean oil or sunflower oil on a weight/weight basis) for 12 weeks. All birds on the high-fat diets were significantly heavier (p < 0.05) after the 12-week feeding period, than when commencing the dietary intervention. Serum triglyceride concentrations of birds in all high-fat diet groups were significantly lower (p < 0.05) than birds in the standard diet group, whereas only birds in the palm oil group had significantly lower (p < 0.05) serum cholesterol concentrations compared to the standard diet group. Fragiligrams of erythrocytes from birds in the various dietary groups were similar. High-fat diet feeding with different types of additional fat did not affect the osmotic fragility of the quail erythrocytes. Feeding quail high-energy diets of varying degrees of fatty acid saturation was well tolerated and did not seem to affect the overall health status of the birds. Resistance of avian erythrocytes to modification by excess dietary fat may be a general characteristic of avian erythrocytes.


Assuntos
Coturnix/fisiologia , Gorduras na Dieta/farmacologia , Eritrócitos/efeitos dos fármacos , Lipídeos/sangue , Fragilidade Osmótica/efeitos dos fármacos , Animais , Peso Corporal , Coturnix/sangue , Coturnix/crescimento & desenvolvimento , Gorduras na Dieta/administração & dosagem , Masculino
9.
S Afr Med J ; 102(5): 307-8, 2012 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-22554339

RESUMO

Each year, 70 000 South Africans are killed by trauma and a further 3.5 million seek trauma care. We analysed 1 465 trauma patients at the regional-level King Edward VIII hospital (KE8H) in eThekwini Municipality. Mean patient age was 29 years. Peaks in patient numbers were observed mid-month, at month-end, between 08h00 and 12h00 daily and on Saturday and Sunday nights. Most injuries occurred on roads, at informal settlements and at bars/shebeens. More than 44% of injuries had a violent cause. The pattern of presentation was more in line with a primary healthcare setting than a referral centre. Reliable and accurate injury trend information is required for effective strategies to curb South Africa's high injury mortality and morbidity rates. Epidemiological databases are needed, as well as safe, robust and ethical systems for collecting, collating, analysing and disseminating non-fatal injury-related data.


Assuntos
Cuidados Críticos/estatística & dados numéricos , Emergências/epidemiologia , Admissão e Escalonamento de Pessoal/estatística & dados numéricos , Sistema de Registros/estatística & dados numéricos , Violência/estatística & dados numéricos , Carga de Trabalho/estatística & dados numéricos , Ferimentos e Lesões/epidemiologia , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , África do Sul/epidemiologia , Traumatismos Torácicos/epidemiologia , Fatores de Tempo , Centros de Traumatologia , Ferimentos por Arma de Fogo/epidemiologia , Adulto Jovem
10.
Pediatr Surg Int ; 28(3): 267-70, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21969235

RESUMO

PURPOSE: Intussusception is a recognised but unusual presenting feature of Burkitt lymphoma. We sought to identify the clinical features associated with intussusception in this setting, and assess the outcome following protocol directed chemotherapy. METHODS: A retrospective case note review was performed on patients treated for Burkitt lymphoma at our institution between 1976 and 2010. Cases presenting with intussusception were identified from hospital records and oncology database. RESULTS: Fourteen of the 210 children seen with a diagnosis of Burkitt lymphoma during the study period (6.7%) developed intussusception. Median age was 6.1 years (range 2.5-10.9). Twelve patients presented with recurrent abdominal pain, and two patients with a jaw mass associated with endemic Burkitt lymphoma. Nine patients underwent a right hemicolectomy with ileo-colic anastomosis, and five had segmental small-bowel resections. Three patients had bone marrow involvement at diagnosis, two of whom died. All patients received chemotherapy. Median follow-up was 6.07 years (range 0.1-28.8). CONCLUSIONS: Small bowel lymphoma should be considered in children presenting with intussusception above the normal infantile peak age range. The presentation is often insidious, and complete obstruction may not be apparent. However, when surgically resected, the majority can achieve a good outcome with additional chemotherapy.


Assuntos
Linfoma de Burkitt/complicações , Doenças do Íleo/etiologia , Intussuscepção/etiologia , Linfoma de Burkitt/diagnóstico , Linfoma de Burkitt/terapia , Criança , Pré-Escolar , Terapia Combinada , Diagnóstico Diferencial , Procedimentos Cirúrgicos do Sistema Digestório/métodos , Feminino , Seguimentos , Humanos , Doenças do Íleo/diagnóstico , Doenças do Íleo/cirurgia , Intussuscepção/diagnóstico , Intussuscepção/cirurgia , Masculino , Estadiamento de Neoplasias , Estudos Retrospectivos , Fatores de Tempo
11.
SADJ ; 66(6): 272, 274-7, 2011 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23198475

RESUMO

Dentistry is a high risk profession for the development of musculoskeletal disorders as it is characterised by visual demands which require the adoption of static working posture. Headaches and vertebral pain has been positively correlated to poor ergonomic working posture adopted by dentists. The aim of this study was to examine the work posture adopted by dentists in the metropolitan region of Durban and Verulam in the province of Kwa-Zulu Natal, South Africa, as well as to report on the prevalence of musculoskeletal pain and discomfort experienced by this cohort. A descriptive survey was conducted among 94 dentists, who voluntarily consented to participate in an occupational, epidemiological retrospective study. Subjects' biographical, occupational, epidemiological and exercise history information was collected by using a self-report questionnaire. All dentists in the metropolitan region of Durban and Verulam were contacted telephonically and those volunteering to participate in the study were subsequently interviewed. During the interview, subjects' body mass and stature were measured using a portable Detecto stadiometer scale. Subjects' waist and hip girths were measured using an anthropometric tape measure around their anterior sacro-iliac crest (waist) and their greater trochanter (hip). In addition to collecting the anthropometric data, the dentists completed a self-report questionnaire and informed consent form. Descriptive statistics comprising of mode, mean, frequency, percentages and chi-square tests (with the probability set at 0.05) were employed in the statistical analysis. The results indicated the preference of different work postures and positions adopted by dentists that contributed to the prevalence of work-related musculoskeletal pain and discomfort (prevalence of 54.26%). The most prevalent work-related musculoskeletal pain sustained by dentists was the vertebrae (49.32%), wrist (18.75%), shoulder (16.66%) and lower leg (12.5%). The mechanism of the musculoskeletal pain was attributed to the poor ergonomic work posture and work position adopted by dentists in relation to their patients. It is concluded that vertebral musculoskeletal pain is most prevalent among dentists practicing in the metropolitan region of Durban and Verulam.


Assuntos
Odontólogos/estatística & dados numéricos , Ergonomia , Doenças Musculoesqueléticas/epidemiologia , Doenças Profissionais/epidemiologia , Adulto , Idoso , Artralgia/epidemiologia , Dor nas Costas/epidemiologia , Estatura , Índice de Massa Corporal , Estudos de Coortes , Estudos Epidemiológicos , Feminino , Humanos , Extremidade Inferior/patologia , Masculino , Pessoa de Meia-Idade , Dor/epidemiologia , Postura/fisiologia , Prevalência , Estudos Retrospectivos , Dor de Ombro/epidemiologia , África do Sul/epidemiologia , Relação Cintura-Quadril , Articulação do Punho/patologia , Adulto Jovem
12.
Ann Neurol ; 68(5): 717-26, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20839240

RESUMO

OBJECTIVE: Centronuclear myopathy (CNM) is a rare congenital myopathy characterized by prominence of central nuclei on muscle biopsy. CNM has been associated with mutations in MTM1, DNM2, and BIN1 but many cases remain genetically unresolved. RYR1 encodes the principal sarcoplasmic reticulum calcium release channel and has been implicated in various congenital myopathies. We investigated whether RYR1 mutations cause CNM. METHODS: We sequenced the entire RYR1 coding sequence in 24 patients with a diagnosis of CNM from South Africa (n = 14) and Europe (n = 10) and identified mutations in 17 patients. The most common genotypes featured compound heterozygosity for RYR1 missense mutations and mutations resulting in reduced protein expression, including intronic splice site and frameshift mutations. RESULTS: The high incidence in South African patients (n = 12/14) in conjunction with recurrent RYR1 mutations associated with common haplotypes suggested the presence of founder effects. In addition to central nuclei, prominent histopathological findings included (often multiple) internalized nuclei and type 1 fiber predominance and hypotrophy with relative type 2 hypertrophy. Although cores were not typically seen on oxidative stains, electron microscopy revealed subtle abnormalities in most cases. External ophthalmoplegia, proximal weakness, and bulbar involvement were prominent clinical findings. INTERPRETATION: Our findings expand the range of RYR1-related phenotypes and suggest RYR1 mutations as a common cause of congenital myopathies with central nuclei. Corresponding to recent observations in X-linked CNM, these findings indicate disturbed assembly and/or malfunction of the excitation-contraction machinery as a key mechanism in CNM and related myopathies.


Assuntos
Músculo Esquelético/patologia , Miopatias Congênitas Estruturais/etiologia , Canal de Liberação de Cálcio do Receptor de Rianodina/genética , Adolescente , Criança , Pré-Escolar , Europa (Continente) , Genótipo , Heterozigoto , Humanos , Masculino , Mutação , Miopatias Congênitas Estruturais/diagnóstico , Miopatias Congênitas Estruturais/genética , Miopatias Congênitas Estruturais/patologia , Fenótipo , Canal de Liberação de Cálcio do Receptor de Rianodina/metabolismo , África do Sul
13.
Neuromuscul Disord ; 20(11): 735-9, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20630756

RESUMO

Polymyositis in HIV-infected subjects, clinically and pathologically resemble polymyositis in non-HIV-infected subjects. We report 14 consecutive HIV-associated polymyositis cases and compare specific features with 25 polymyositis cases seen over the same 6.5 year period. The HIV-polymyositis cases were all female and compared to the polymyositis cases were younger (median age 33 years, interquartile range (IQR) 29; 37 vs. 46 years, IQR 38; 52, p=0.002), and with 4-fold lower serum creatine kinase (CK) values (median 1158 vs. 5153IU/l; p=0.019). A definite clinical improvement on prednisone therapy was documented in eight HIV-polymyositis cases and one improved with anti-retroviral therapy alone. The recognition of HIV-polymyositis which is treatable, but may present with serum CK elevations less than twofolds above normal, is clinically relevant in sub-Saharan Africa where electromyography and muscle biopsies are not readily available.


Assuntos
Infecções por HIV/complicações , Músculo Esquelético/patologia , Polimiosite/complicações , Adulto , Anti-Inflamatórios/uso terapêutico , População Negra , Creatina Quinase/sangue , Feminino , Infecções por HIV/sangue , Infecções por HIV/patologia , Humanos , Pessoa de Meia-Idade , Polimiosite/sangue , Polimiosite/tratamento farmacológico , Polimiosite/patologia , Prednisona/uso terapêutico , África do Sul , Estatísticas não Paramétricas , Resultado do Tratamento
16.
J Hazard Mater ; 166(2-3): 1067-75, 2009 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-19157694

RESUMO

The adsorption capabilities for the removal of parts per billion levels (ppb) of hexavalent chromium by three adsorbents namely activated carbon, functionalized multi-walled carbon nanotubes (MWCNTs) and unfunctionalized multi-walled carbon nanotubes were investigated as a function of contact time, initial solution pH, initial Cr(VI) concentrations and the presence of competing anions. The unfunctionalized MWCNTs showed the highest adsorption capability with up to 98% of a 100 ppb Cr(VI) solution being adsorbed. Both functionalized and non-functionalized MWCNTs showed a superior adsorption capability to that of activated carbon. The removal of Cr(VI) was higher at lower pH. Furthermore, the uptake of Cr(VI) was hindered by the presence of the competing anions, Cl(-) and SO(4)(2-). Both Langmuir and Freundlich isotherms have been used to describe the Cr(VI) adsorption process. The major mechanisms for Cr(VI) removal have been identified as an ion exchange mechanism, intraparticle diffusion and electrostatic interactions. The adsorbed Cr(VI) could also be desorbed readily from the MWCNTs surface at high pH.


Assuntos
Cromo/isolamento & purificação , Nanotubos de Carbono/química , Poluentes Químicos da Água/isolamento & purificação , Adsorção , Ânions , Concentração de Íons de Hidrogênio , Cinética , Soluções , Purificação da Água/métodos
17.
S. Afr. j. clin. nutr. (Online) ; 22(2): 95-98, 2009.
Artigo em Inglês | AIM (África) | ID: biblio-1270496

RESUMO

Objectives: The objective of this study was to assess the dietary intake and metabolic control of children with type 1 diabetes. Design: A cross-sectional observational study was carried out. Subjects: A total of 30 subjects whose ages ranged from six to ten years were included in the study. Setting: The study was conducted at the Paediatric Diabetic Clinics at Grey's Hospital; Pietermaritzburg and Inkosi Albert Luthuli Central Hospital (IALCH); Durban; in KwaZulu-Natal. Outcome measures: Dietary intake was assessed using a three-day dietary record. Metabolic control was assessed using glycosylated haemoglobin (HbA1c). Results: The mean percentage contributions of macronutrients to total energy as determined by the three-day dietary records were as follows: carbohydrate - 52; added sucrose - 2; protein - 16; fat - 32. The mean intakes were similar to the recommendations of the International Society for Pediatric and Adolescent Diabetes (ISPAD) Consensus Guidelines (2002). Micronutrient intake was generally adequate. The mean latest glycosylated haemoglobin (HbA1c) for the sample as at the time of the study was 9.7. Five of the thirty subjects had HbA1c values that were within the recommended levels for children with type 1 diabetes. Conclusions: The macronutrient intake in this sample was found to be similar to the ISPAD Consensus Guidelines (2002) while micronutrient intake was adequate in most cases. Overall the sample had poor metabolic control


Assuntos
Criança , Estudos Transversais , Diabetes Mellitus
18.
Sex Transm Infect ; 83(7): 530-3, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17971375

RESUMO

OBJECTIVES: A study of men with genital ulcer disease (GUD) in Durban, South Africa, at the start of the local HIV epidemic in 1988/1989 found that 36% of men with GUD continued with sexual intercourse despite symptoms. The aim of this study was to determine whether this high-risk behaviour was still prevalent and to enquire about similar risk behaviours with other sexually transmitted infection (STI)-related problems. METHODS: 650 Men attending the main Durban STI clinic with a new complaint were enrolled. A standard questionnaire was administered. Polymerase chain reaction (PCR) tests were performed to diagnose genital herpes from ulcer specimens and gonorrhoea and chlamydia from those with urethral discharge and/or dysuria. Serology tests were performed for HIV, herpes simplex virus type 2 (HSV-2) and syphilis. RESULTS: Sex since the start of symptoms was reported by between 33.3% and 43.9% of men with GUD, herpetic ulcers, gonorrhoea and/or chlamydia or dysuria. The incidence of condom use was very low in all groups having sex despite symptoms. In 87 men with genital ulcers confirmed positive for genital herpes by PCR testing, 30 (34.4%) had had sex since the start of symptoms, 28 (93.3%) of whom had had unprotected sex. CONCLUSIONS: There is a high level of risk behaviour in this group of men in whom genital herpes is the most common cause of GUD. This risky sexual behaviour could reflect disinhibition, possibly because so many have already been infected with HSV-2, lack of education or other unknown factors. Syndromic STI management should be strengthened with intensive health education to promote community awareness of both genital ulceration and genital herpes and their role in facilitating HIV transmission. The low level of condom use indicates that condom promotion programmes still have much to achieve.


Assuntos
Infecções por Chlamydia/psicologia , Gonorreia/psicologia , Herpes Genital/psicologia , Sexo sem Proteção/estatística & dados numéricos , Adulto , Assistência Ambulatorial/estatística & dados numéricos , Anticorpos Antivirais/sangue , Infecções por Chlamydia/epidemiologia , Gonorreia/epidemiologia , Herpes Genital/epidemiologia , Humanos , Masculino , Aceitação pelo Paciente de Cuidados de Saúde , Reação em Cadeia da Polimerase/métodos , Prevalência , África do Sul/epidemiologia
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