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1.
Epidemiol Infect ; 148: e147, 2020 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-32605670

RESUMEN

Major surgery carried out in low- and middle-income countries is associated with a high risk of surgical site infections (SSI), but knowledge is limited regarding contributory factors to such infections. This study explores factors related to patients developing an SSI in a teaching hospital in Ghana. A prospective cohort study of patients undergoing abdominal surgical procedures was conducted at Korle Bu Teaching Hospital. Patient characteristics, procedures and environmental characteristics were recorded. A 30-day daily surveillance was used to diagnose SSI, and Poisson regression analysis was used to test for association of SSI and risk factors; survival was determined by proportional hazard regression methods. We included 358 patients of which 58 (16.2%; 95% CI 12.7-20.4%) developed an SSI. The median number of door openings during an operation was 79, with 81% being unnecessary. Door openings greater than 100 during an operation (P = 0.028) significantly increased a patient's risk of developing an SSI. Such patients tended to have an elevated mortality risk (hazard ratio 2.67; 95% CI 0.75-9.45, P = 0.128). We conclude that changing behaviour and practices in operating rooms is a key strategy to reduce SSI risk.


Asunto(s)
Abdomen/cirugía , Microbiología del Aire , Infección de la Herida Quirúrgica/epidemiología , Infección de la Herida Quirúrgica/microbiología , Adulto , Femenino , Ghana/epidemiología , Hospitales de Enseñanza , Humanos , Masculino , Persona de Mediana Edad , Movimiento , Quirófanos , Estudios Prospectivos , Factores de Riesgo
2.
J Hosp Infect ; 104(3): 321-327, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31931045

RESUMEN

BACKGROUND: Surveillance systems for surgical site infections (SSIs), as a measure of patient safety, help health institutions devise strategies to reduce or prevent them. No surveillance systems exist to monitor SSIs in Ghana. AIM: To establish a system for monitoring trends and detecting outbreaks in order to create awareness of and control SSIs. METHODS: An active 30-day surveillance was undertaken at the general surgical unit of the Korle Bu Teaching Hospital, from July 1st, 2017 to December 31st, 2018 to identify SSI. It involved a daily inpatient surveillance of patients who had had a surgical procedure, followed by post-discharge surveillance by means of a healthcare personnel-based survey and a patient-based telephone survey. We supplied quarterly feedback of results to surgeons. FINDINGS: Among the 3267 patients included, 331 were identified with an SSI, a 10% incidence risk. Patients who acquired an SSI experienced increased morbidity including nine extra days in hospital and an adjusted relative mortality risk of 2.3 (95% confidence interval: 1.3 - 4.1; P=0.006) compared to patients without SSI. Forty-nine per cent (161/331) of SSIs were diagnosed post discharge using the healthcare personnel-based survey. The patient-based telephone survey contributed 12 additional cases. SSI incidence risk decreased from 12.8% to 7.5% during the study period. CONCLUSION: Post-discharge surveillance is feasible using existing healthcare personnel, and the results highlight the high risk and burden of SSIs in Ghana. A surveillance system with feedback for monitoring SSIs may contribute to reducing SSIs; however, firm conclusions regarding the impact need longer observation time.


Asunto(s)
Infección Hospitalaria/epidemiología , Seguridad del Paciente , Infección de la Herida Quirúrgica/epidemiología , Adolescente , Adulto , Anciano , Niño , Estudios de Cohortes , Femenino , Ghana , Hospitales de Enseñanza , Humanos , Masculino , Persona de Mediana Edad , Vigilancia de la Población , Estudios Prospectivos , Factores de Riesgo , Infección de la Herida Quirúrgica/prevención & control , Adulto Joven
3.
J Hosp Infect ; 101(1): 60-68, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-29730140

RESUMEN

BACKGROUND: There is a paucity of data describing hospital-acquired infections (HAIs) in Africa. OBJECTIVE: To describe the prevalence and distribution of HAIs in acute care hospitals in Ghana. METHODS: Between September and December 2016, point-prevalence surveys were conducted in participating hospitals using protocols of the European Centre for Disease Prevention and Control. Medical records of eligible inpatients at or before 8am on the survey date were reviewed to identify HAIs present at the time of the survey. FINDINGS: Ten hospitals were surveyed, representing 32.9% of all acute care beds in government hospitals. Of 2107 inpatients surveyed, 184 HAIs were identified among 172 patients, corresponding to an overall prevalence of 8.2%. The prevalence values in hospitals ranged from 3.5% to 14.4%, with higher proportions of infections in secondary and tertiary care facilities. The most common HAIs were surgical site infections (32.6%), bloodstream infections (19.5%), urinary tract infections (18.5%) and respiratory tract infections (16.3%). Device-associated infections accounted for 7.1% of HAIs. For 12.5% of HAIs, a micro-organism was reported; the most commonly isolated micro-organism was Escherichia coli. Approximately 61% of all patients surveyed were on antibiotics; 89.5% of patients with an HAI received at least one antimicrobial agent on the survey date. The strongest independent predictors for HAI were the presence of an invasive device before onset of infection and duration of hospital stay. CONCLUSION: A low HAI burden was found compared with findings from other low- and middle-income countries.


Asunto(s)
Infección Hospitalaria/epidemiología , Infecciones del Sistema Respiratorio/epidemiología , Sepsis/epidemiología , Infección de la Herida Quirúrgica/epidemiología , Infecciones Urinarias/epidemiología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Preescolar , Estudios Transversales , Escherichia coli/aislamiento & purificación , Femenino , Ghana/epidemiología , Hospitales Públicos , Humanos , Lactante , Recién Nacido , Masculino , Persona de Mediana Edad , Adulto Joven
4.
Phys Chem Chem Phys ; 19(7): 5246-5253, 2017 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-28149993

RESUMEN

The key challenges for perovskite solar cells include their poor stability and film homogeneity. Studying the degradation and homogeneity of perovskite layers within device structures can be challenging but critical to the understanding of stability and effect of processing in real life conditions. We show that Raman spectroscopy (RS) is a unique and powerful method (simple and fast) to probe the degradation of the perovskite film within the device structure and image perovskite formation. We demonstrate that RS can be used to directly probe chemical (PbI2) and physical (dihydrated phase) degradation of a perovskite film, and estimate the relative amount of the degradation species formed, mapping its distribution with ∼1 µm spatial resolution. This has been applied to mapping a large area perovskite module to characterise the efficacy of PbI2 to perovskite conversion. We also use RS to study the degradation species and kinetics under diverse accelerated degradation conditions (temperature and humidity) in situ. These capabilities are difficult to achieve with other methods, presenting RS as an important tool to gain understanding of the degradation and effect of processing on perovskite-based photovoltaic devices.

5.
Epidemiol Infect ; 144(15): 3288-3299, 2016 11.
Artículo en Inglés | MEDLINE | ID: mdl-27334298

RESUMEN

Poultry are possible sources of non-typhoidal Salmonella serovars which may cause foodborne human disease. We conducted a cross-sectional study to determine the prevalence of Salmonella serovars in egg-laying hens and broilers at the farm level and their susceptibility to antimicrobials commonly used in the poultry industry in Ghana. Sampling of faeces by a sock method (n = 75), dust (n = 75), feed (n = 10) and drinking water (n = 10) was performed at 75 commercial egg-laying and broiler farms in two regions of Ghana and skin neck (n = 30) at a local slaughterhouse from broilers representing different flocks. Salmonella was detected in 94/200 (47%) samples with an overall flock prevalence of 44·0%. Sixteen different serovars were identified with S. Kentucky (18·1%), S. Nima (12·8%), S. Muenster (10·6%), S. Enteritidis (10·6%) and S. Virchow (9·6 %) the most prevalent types. The predominant phage type of S. Enteritidis was PT1. All strains were susceptible to cefotaxime, ceftazidime and cefoxitin. Fifty-seven (60·6%) strains were resistant to one or more of the remaining nine antimicrobials tested by disk diffusion, of which 23 (40·4%) showed multi-resistance (resistance to ⩾3 classes of antimicrobials). Of the resistant strains (n = 57), the most significant were to nalidixic acid (89·5%), tetracycline (80·7%), ciprofloxacin (64·9%), sulfamethazole (42·1%), trimethoprim (29·8%) and ampicillin (26·3%). All S. Kentucky strains were resistant to more than two antimicrobials and shared common resistance to nalidixic acid or ciprofloxacin and tetracycline, often in combinations with other antimicrobials. PFGE analysis using XbaI of S. Kentucky demonstrated one dominant clone in the country. In conclusion, poultry produced in Ghana has a high prevalence of multi-resistant Salmonella and the common finding of clonal S. Kentucky in the Kumasi area warrants further investigations into the epidemiology of this serovar. There is an urgent need for surveillance and control programmes on Salmonella and use of antimicrobials in the Ghanaian poultry industry to protect the health of consumers.


Asunto(s)
Antibacterianos/farmacología , Farmacorresistencia Bacteriana Múltiple , Enfermedades de las Aves de Corral/epidemiología , Salmonelosis Animal/epidemiología , Salmonella/aislamiento & purificación , Animales , Pollos , Estudios Transversales , Electroforesis en Gel de Campo Pulsado/veterinaria , Femenino , Ghana/epidemiología , Pruebas de Sensibilidad Microbiana/veterinaria , Enfermedades de las Aves de Corral/microbiología , Prevalencia , Salmonella/genética , Salmonelosis Animal/microbiología , Serogrupo
6.
J Infect Prev ; 17(4): 179-184, 2016 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28989477

RESUMEN

INTRODUCTION: Antimicrobial resistance (AMR) represents a growing threat to public health, with the potential to reverse many of the gains made in modern medicine. AMR is contributed to by both inappropriate choice of antibiotics and inappropriate antibiotic course durations. OBJECTIVES: The objective of this audit was to determine if the introduction of antimicrobial prescribing electronic prompts in an electronic patient record had a positive impact on antimicrobial stewardship. METHODS: The audit examined the proportion of antibiotic prescriptions within a critical care unit in which both a valid stop date and indication were recorded. The audit was repeated on two occasions: first, after an education programme, and second, after the introduction of an electronic prompt within the patients' electronic patient record. RESULTS: Chi-square analyses indicated that significant improvements in both the recording of indications (χ²(4) = 39.69, P <0.0001) and stop-dates (χ²(4) = 42.10, P <0.0001) occurred across the three audits. CONCLUSION: We conclude that the novel use of daily electronic prompts has a positive impact on antimicrobial stewardship.

7.
Ghana Med J ; 49(3): 154-8, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26693190

RESUMEN

INTRODUCTION: Asymptomatic bacteriuria, the presence of bacteria in urine without symptoms of acute urinary tract infection, predisposes pregnant women to the development of urinary tract infections and pyelonephritis, with an attendant pregnancy related complications. OBJECTIVE: To measure the prevalence of asymptomatic bacteriuria among ante-natal clients at the Korle-Bu Teaching Hospital in Ghana and its' associated risk factors. METHODS: A cross-sectional study involving 274 antenatal clients was conducted over a period of 4 weeks. A face to face questionnaire was completed and midstream urine collected for culture and antimicrobial susceptibility testing. RESULTS: The prevalence of asymptomatic bacteriuria was 5.5%. It was associated with sexual activity during pregnancy (Fisher's Exact 5.871, p-value 0.0135), but not with sexual frequency. There were no significant associations with educational status, parity, gestational age, marital status and the number of foetuses carried. The commonest organism isolated was Enterococcus spp (26.7%) although the enterobacteriaceae formed the majority of isolated organisms (46.7%). Nitrofurantoin was the antibiotic with the highest sensitivity to all the isolated organisms. CONCLUSIONS: The prevalence of asymptomatic bacteriuria among ante-natal clients at this large teaching hospital in Ghana is 5.5%, which is lower than what has been found in other African settings. Enterococcus spp was the commonest causative organism. However, due to the complications associated with asymptomatic bacteriuria, a policy to screen and treat- all pregnant women attending the hospital, is worth considering.


Asunto(s)
Infecciones Asintomáticas/epidemiología , Bacteriuria/diagnóstico , Bacteriuria/epidemiología , Enterococcus/aislamiento & purificación , Complicaciones Infecciosas del Embarazo/diagnóstico , Adolescente , Adulto , Antibacterianos/uso terapéutico , Bacteriuria/tratamiento farmacológico , Estudios Transversales , Femenino , Ghana , Hospitales de Enseñanza , Humanos , Pruebas de Sensibilidad Microbiana , Embarazo , Atención Prenatal , Factores de Riesgo , Adulto Joven
8.
Anaesth Intensive Care ; 38(2): 373-5, 2010 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-20369776

RESUMEN

A 30-year-old woman developed total spinal anaesthesia during establishment of labour analgesia via an epidural catheter The subsequent respiratory failure was successfully managed with non-invasive ventilation. This report describes the use of non-invasive ventilation in the parturient and the process of managing the parturient safely in an appropriately monitored environment. This case displays the potential benefit of this technique in the setting of a total spinal block in preventing the need for intubation and ventilation (and subsequent emergency caesarean section) and providing adequate ventilatory function until the block subsided adequately.


Asunto(s)
Analgesia Epidural/efectos adversos , Analgesia Obstétrica/efectos adversos , Insuficiencia Respiratoria/etiología , Adulto , Femenino , Hemodinámica , Humanos , Embarazo , Insuficiencia Respiratoria/terapia
10.
West Afr J Med ; 28(5): 300-3, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-20383833

RESUMEN

BACKGROUND: Nosocomial or hospital acquired infection has been recognized as a serious public health problem in the last twenty years. In most hospitals in Africa-South of the Sahara, although the types of community acquired infections are known, neither the magnitude, nor the common types of nosocomial infections has been documented. OBJECTIVE: This study was carried out to find the prevalence of hospital and community acquired infections in hospitals, and to estimate the overall prevalence of HAI and CAI in Korle Bu Teaching Hospital. METHODS: A one-day prevalence survey of nosocomial and community acquired infection in a tertiary-care hospital in Accra was performed using the 1980 British national protocol and the result was analyzed using computerized gargets. RESULTS: Of the 907 patients on admission (on the day of the study), 61 (6.7%) had hospital-acquired infection and 287 (31.6%) had community acquired infection. The commonest hospital acquired infection was wound infection followed by skin and lower respiratory infections. Of the community infections, the most common cases were lower respiratory and skin infections. Fifty-three percent of all patients were on antimicrobial treatment. Patients on metronidazole were 212 (44%), ampicillin/amoxicillin 199 (41.6%), cloxacillin 163 (34%) and gentamicin 135 (28%). Approximately 20% of patients were on three or more drugs. CONCLUSION: This study has shown that the prevalence of community acquired infections in our hospital is much higher than that from nosocomial infections and that the British national survey protocol can be used in countries with limited resources.


Asunto(s)
Infecciones Comunitarias Adquiridas/epidemiología , Infección Hospitalaria/epidemiología , Infecciones Comunitarias Adquiridas/prevención & control , Infección Hospitalaria/prevención & control , Femenino , Ghana/epidemiología , Hospitales de Enseñanza/estadística & datos numéricos , Humanos , Masculino , Vigilancia de la Población/métodos , Prevalencia
11.
Anaesth Intensive Care ; 36(1): 96-101, 2008 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-18326140

RESUMEN

Immediate management of inadvertent dural puncture during insertion of an epidural needle during labour is controversial and evidence to guide clinical practice is limited. We surveyed Australian obstetric anaesthetists by anonymous postal questionnaire. Of the 671 surveys sent, 417 (62%) were returned. Following dural puncture, 265 respondents (64%) indicated that they "would usually remove the Tuohy needle and resite". The most common reason for this decision was concern regarding the safety of intrathecal catheters (ITC) (n = 236, 89%), in particular, the risk of misuse (n = 182, 70%). The most frequently reported reason for "usually inserting an ITC" was that this reduced the incidence (n = 120, 84%) and severity (n = 110, 77%) of post dural puncture headache. Increased frequency of ITC insertion was reported by respondents who practised more frequent sessions of obstetric anaesthesia, had fewer years of experience as a consultant anaesthetist and worked in a public hospital. The more widespread use of ITCs seems to be limited by safety concerns.


Asunto(s)
Analgesia Epidural/efectos adversos , Analgesia Obstétrica/efectos adversos , Duramadre/lesiones , Trabajo de Parto , Punción Espinal/efectos adversos , Analgesia Epidural/instrumentación , Analgesia Obstétrica/instrumentación , Anestesiología/métodos , Anestesiología/normas , Australia , Femenino , Encuestas de Atención de la Salud/estadística & datos numéricos , Humanos , Inyecciones Espinales/efectos adversos , Inyecciones Espinales/instrumentación , Errores Médicos , Agujas/efectos adversos , Cefalea Pospunción de la Duramadre/etiología , Cefalea Pospunción de la Duramadre/prevención & control , Pautas de la Práctica en Medicina/estadística & datos numéricos , Embarazo , Australia del Sur , Punción Espinal/instrumentación
12.
West Afr J Med ; 26(2): 131-3, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-17939315

RESUMEN

BACKGROUND: The level of drug resistance in mycobacterial isolates from previously treated cases in Ghana is not known although drug resistant tuberculosis threatens efforts to control the disease. OBJECTIVE: To identify and determine the susceptibility of mycobacterial isolates from tuberculosis cases with clinical treatment failure. METHODS: This prospective survey was undertaken at the Chest Clinic of Korle Bu Teaching Hospital in Accra, Ghana. The participants were twenty-eight cases referred to the hospital with clinical treatment failure. Two sputum specimens from each case were stained by Ziehl-Neelsen method, cultured, identified and sensitivity tests performed by the proportion method. RESULTS: Eighteen isolates of mycobacteria were identified from 28 failed treatment cases. Five were atypical mycobacteria. Approximately fifty percent (13/28) of cases had Mycobacterium tuberculosis, 5(18%) had atypical mycobacteria, 7(25%) had pure fungal growth and 3(11% 8) had no growth. Fifteen isolates were resistant to two or more drugs, of which 6 were resistant to all four drugs tested. CONCLUSION: Continuous drug resistance monitoring must be instituted as part of the tuberculosis control programme.


Asunto(s)
Susceptibilidad a Enfermedades , Farmacorresistencia Bacteriana , Mycobacterium/efectos de los fármacos , Insuficiencia del Tratamiento , Tuberculosis Pulmonar/microbiología , Antibacterianos/farmacología , Femenino , Ghana , Encuestas Epidemiológicas , Hospitales de Enseñanza , Humanos , Masculino , Mycobacterium/aislamiento & purificación , Estudios Prospectivos , Esputo
13.
East Afr Med J ; 84(3): 136-40, 2007 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-17600983

RESUMEN

BACKGROUND: Most neonatal deaths in developing countries are caused by infections, birth asphyxia and prematurity. Even though most of these deaths occur at home, newborns admitted to hospital neonatal units have a high risk of contracting fatal multi-drug resistant infections. OBJECTIVE: To compare the type of bacteria and the pattern of antimicrobial susceptibility of organisms causing neonatal infections in 2001/02 with 1991/92 in the same neonatal unit. DESIGN: We reviewed the hospital records of newborns admitted to the neonatal unit in 2001/02 that had positive blood cultures and compared the findings with similar work done 1991/92. SETTING: Neonatal Unit, Korle Bu Teaching Hospital, Ghana. RESULTS: Gram negative organisms (predominantly Enterobacter, Klebsiella and Acinetobacter) remained the predominant cause of neonatal infection. There was a reduction in the proportion of gram negative bacteraemia [70.9% in 1991/92 vs. 54.2% in 2001/02 (p<0.001)] due to the increased prevalence of coagulase negative staphylococcus (31.9% in 2001/02 vs. 0% in 1991/92) as a cause of neonatal bacteraemia ten years later. In 1991/92 as 2001/02 all bacterial isolates showed less than 40% susceptibility to ampicillin. The susceptibility of Klebsiella and Enterobacter to commonly used aminoglycosides and cephalosporins had decreased from over 80% in 1991/92 to less than 35% in 2001/02. CONCLUSION: Bacterial causes of neonatal infections change over time and antimicrobial resistance is a major cause for concern in neonatal units in resource-poor hospitals. Improving infection control practices and instituting systems to monitor antimicrobial use and resistance will compliment community efforts to reduce neonatal mortality.


Asunto(s)
Infecciones Bacterianas/microbiología , Bacterias Gramnegativas/aislamiento & purificación , Bacterias Grampositivas/aislamiento & purificación , Infecciones Bacterianas/epidemiología , Ghana/epidemiología , Hospitales de Enseñanza , Humanos , Recién Nacido
14.
West Afr J Med ; 24(3): 219-22, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-16276698

RESUMEN

OBJECTIVE: To determine the vaginal flora of first time urban Family Planning clients at Korle-Bu Teaching Hospital and to assess its implications for the contraceptive choices made. DESIGN: A cross sectional study. METHODS: A standardized questionnaire surveying the sociodemographic characteristics and the choice of Family Planning method was administered to 100 clients at the Korle Bu Teaching Hospital between March and September 2001. High vaginal and endocervical swabs were also taken during the inspection of the vagina and cervix using a sterile bivalve speculum. The specimens were transported in Amies transport medium to the Microbiology laboratory for processing. RESULTS: The age range of the clients was 19-48 years with a modal age of 28 years. Ninety-six percent of them were married while 86% lived in urban slums. Sixty-three percent were sure of their last menstrual period. Potential pathogens were isolated from culture in 56% of the clients. Organisms causing bacterial vaginosis were the most prevalent in their genital tract. The intrauterine contraceptive device (IUCD) was the most common Family Planning method chosen, followed by the Norplant and the Depo-Provera injections. Potential pathogens were isolated from culture in 50% of those who chose the IUCD. CONCLUSION: Potential pathogens were isolated from culture in 56% of these first-time clients and organisms causing bacterial vaginosis were the most prevalent in the genital tract. It is suggested that Family Planning clients who screened positive for potential pathogens and opt for the IUCD should be considered for prophylactic antibiotics at insertion.


Asunto(s)
Instituciones de Atención Ambulatoria/estadística & datos numéricos , Salud Urbana , Vagina/microbiología , Vaginosis Bacteriana/diagnóstico , Adulto , Recuento de Colonia Microbiana , Anticoncepción/métodos , Estudios Transversales , Femenino , Ghana , Hospitales de Enseñanza , Humanos , Persona de Mediana Edad , Encuestas y Cuestionarios , Frotis Vaginal , Vaginosis Bacteriana/microbiología
15.
East Afr Med J ; 81(8): 398-401, 2004 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-15622933

RESUMEN

OBJECTIVES: To determine the carriage rates of potential pathogens in the lower genital tract and factors associated with colonization among women with incomplete abortion. DESIGN: A cross-sectional study. SETTING: The Manual Vacuum Aspiration room of the Korle-Bu Teaching Hospital, Accra, Ghana. SUBJECTS: Two hundred women undergoing Manual Vacuum Aspiration at the Korle-Bu Teaching Hospital. METHODS: Eligible patients were screened for the presence of organisms in the lower genital tract by microscopy and culture of high vaginal and endocervical swabs. RESULTS: Nearly two-thirds of the patients (64.2%) had potential pathogens in the lower genital tract. Bacterial vaginosis alone was present in 47% and a combination of bacterial vaginosis and Candida albicans was present in 17.2%. Residence in an urban slum showed a significant association with the presence of potential pathogens (Odds ratio 2.6; p-value 0.04). CONCLUSION: Organisms responsible for bacterial vaginosis were the most frequently isolated potential pathogens in the cervical canal of patients with incomplete abortion at the Korle-Bu Teaching Hospital. Management of these patients should therefore include antibiotic prophylaxis against bacterial vaginosis.


Asunto(s)
Aborto Incompleto , Candidiasis Vulvovaginal/microbiología , Portador Sano/microbiología , Legrado por Aspiración/estadística & datos numéricos , Vaginosis Bacteriana/microbiología , Aborto Incompleto/epidemiología , Aborto Incompleto/etiología , Aborto Incompleto/cirugía , Aborto Inducido/efectos adversos , Aborto Espontáneo/complicaciones , Adolescente , Adulto , Distribución por Edad , Candidiasis Vulvovaginal/complicaciones , Candidiasis Vulvovaginal/tratamiento farmacológico , Candidiasis Vulvovaginal/epidemiología , Portador Sano/tratamiento farmacológico , Portador Sano/epidemiología , Estudios Transversales , Femenino , Ghana/epidemiología , Hospitales de Enseñanza , Humanos , Áreas de Pobreza , Embarazo , Características de la Residencia/estadística & datos numéricos , Factores de Riesgo , Factores Socioeconómicos , Encuestas y Cuestionarios , Salud Urbana/estadística & datos numéricos , Frotis Vaginal , Vaginosis Bacteriana/complicaciones , Vaginosis Bacteriana/tratamiento farmacológico , Vaginosis Bacteriana/epidemiología
16.
Br J Ophthalmol ; 86(11): 1211-5, 2002 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-12386069

RESUMEN

BACKGROUND: A multicentre study was carried out in Ghana and southern India to determine the aetiology of suppurative keratitis in two regions located at similar tropical latitudes. Studies of fungal keratitis from the literature were reviewed. METHODS: Patients presenting at rural and urban eye units with suspected microbial keratitis were recruited to the study. Corneal ulceration was defined as loss of corneal epithelium with clinical evidence of infection with or without hypopyon. Microscopy and culture were performed on all corneal specimens obtained. RESULTS: 1090 patients were recruited with suspected microbial keratitis between June 1999 and May 2001. Overall the principal causative micro-organisms in both regions were filamentous fungi (42%): Fusarium species and Aspergillus species were the commonest fungal isolates. Pseudomonas species were most frequently isolated from cases of bacterial keratitis in Ghana but in India the commonest bacterial isolates were streptococci. CONCLUSION: Infections of the cornea due to filamentous fungi are a frequent cause of corneal damage in developing countries in the tropics and are difficult to treat. Microscopy is an essential tool in the diagnosis of these infections. A knowledge of the "local" aetiology within a region is of value in the management of suppurative keratitis in the event that microscopy cannot be performed.


Asunto(s)
Úlcera de la Córnea/microbiología , Infecciones Fúngicas del Ojo/epidemiología , Aspergilosis/epidemiología , Úlcera de la Córnea/epidemiología , Infecciones Bacterianas del Ojo/epidemiología , Infecciones Fúngicas del Ojo/microbiología , Fusarium , Ghana/epidemiología , Humanos , India/epidemiología , Queratitis/epidemiología , Queratitis/microbiología , Prevalencia , Estudios Prospectivos , Infecciones por Pseudomonas/epidemiología
17.
Biochemistry ; 40(49): 14812-20, 2001 Dec 11.
Artículo en Inglés | MEDLINE | ID: mdl-11732900

RESUMEN

Utilizing structure-based design, we have previously demonstrated that it is possible to obtain selective inhibitors of protein-tyrosine phosphatase 1B (PTP1B). A basic nitrogen was introduced into a general PTP inhibitor to form a salt bridge to Asp48 in PTP1B and simultaneously cause repulsion in PTPs containing an asparagine in the equivalent position [Iversen, L. F., et al. (2000) J. Biol. Chem. 275, 10300-10307]. Further, we have recently demonstrated that Gly259 in PTP1B forms the bottom of a gateway that allows easy access to the active site for a broad range of substrates, while bulky residues in the same position in other PTPs cause steric hindrance and reduced substrate recognition capacity [Peters, G. H., et al. (2000) J. Biol. Chem. 275, 18201-18209]. The current study was undertaken to investigate the feasibility of structure-based design, utilizing these differences in accessibility to the active site among various PTPs. We show that a general, low-molecular weight PTP inhibitor can be developed into a highly selective inhibitor for PTP1B and TC-PTP by introducing a substituent, which is designed to address the region around residues 258 and 259. Detailed enzyme kinetic analysis with a set of wild-type and mutant PTPs, X-ray protein crystallography, and molecular modeling studies confirmed that selectivity for PTP1B and TC-PTP was achieved due to steric hindrance imposed by bulky position 259 residues in other PTPs.


Asunto(s)
Diseño de Fármacos , Inhibidores Enzimáticos/química , Proteínas Tirosina Fosfatasas/antagonistas & inhibidores , Proteínas Tirosina Fosfatasas/química , Animales , Sitios de Unión , Clonación Molecular , Cristalografía por Rayos X , Humanos , Isoenzimas/antagonistas & inhibidores , Isoenzimas/química , Isoenzimas/genética , Isoenzimas/metabolismo , Modelos Moleculares , Estructura Molecular , Estructura Secundaria de Proteína , Proteína Tirosina Fosfatasa no Receptora Tipo 1 , Proteínas Tirosina Fosfatasas/genética , Proteínas Tirosina Fosfatasas/metabolismo
18.
Hum Immunol ; 62(11): 1200-16, 2001 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11704282

RESUMEN

The A*0201, A *0202, A*0203, A*0206, and A*6802 binding capacity of single amino acid substitution analogs of known A2-supertype binding peptides and of large nonredundant peptide libraries was measured. The results were utilized to rigorously define the peptide binding specificities of these A2-supertype molecules. Although each molecule was noted to have unique preferences, large overlaps in specificity were found. The presence of L, I, V, M, A, T, and Q residues in position 2, and L, I, V, M, A, and T residues at the C-terminus of peptide ligands were tolerated by all molecules. Likewise, whereas examination of secondary influences on peptide binding revealed allele specific preferences, shared features could also be identified. These shared features were utilized to define an A2-supermotif and were noted to correlate with crossreactivity. Over 70% of the peptides that bound A *0201 with high affinity were found to bind at least two other A2-supertype molecules. Because the A2-supertype molecules studied herein cover the variants most common in different major ethnicities, these findings have important implications for epitope-based approaches to vaccination, immunotherapy, and the monitoring of immune responses.


Asunto(s)
Antígeno HLA-A2/metabolismo , Péptidos/metabolismo , Alelos , Secuencias de Aminoácidos , Sitios de Unión , Reacciones Cruzadas , Antígeno HLA-A2/química , Antígeno HLA-A2/genética
20.
J Immunol ; 165(11): 6387-99, 2000 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-11086077

RESUMEN

Single amino acid substitution analogs of the known Mamu A*01 binding peptide gag 181-190 and libraries of naturally occurring sequences of viral or bacterial origin were used to rigorously define the peptide binding motif associated with Mamu A*01 molecules. The presence of S or T in position 2, P in position 3, and hydrophobic or aromatic residues at the C terminus is associated with optimal binding capacity. At each of these positions, additional residues are also tolerated but associated with significant decreases in binding capacity. The presence of at least two preferred and one tolerated residues at the three anchor positions is necessary for good Mamu A*01 binding; optimal ligand size is 8-9 residues. This detailed motif has been used to map potential epitopes from SIVmac239 regulatory proteins and to engineer peptides with increased binding capacity. A total of 13 wild type and 17 analog candidate epitopes were identified. Furthermore, our analysis reveals a significantly lower than expected frequency of epitopes in early regulatory proteins, suggesting a possible evolutionary- and/or immunoselection directed against variants of viral products that contain CTL epitopes.


Asunto(s)
Antígenos de Histocompatibilidad Clase I/metabolismo , Fragmentos de Péptidos/metabolismo , Virus de la Inmunodeficiencia de los Simios/inmunología , Proteínas Reguladoras y Accesorias Virales/metabolismo , Algoritmos , Sustitución de Aminoácidos , Aminoácidos/metabolismo , Animales , Sitios de Unión/inmunología , Epítopos de Linfocito T/metabolismo , Proteínas Inmediatas-Precoces/síntesis química , Proteínas Inmediatas-Precoces/metabolismo , Ligandos , Macaca mulatta , Oligopéptidos/síntesis química , Oligopéptidos/metabolismo , Fragmentos de Péptidos/síntesis química , Mapeo Peptídico , Unión Proteica/inmunología , Ingeniería de Proteínas , Virus de la Inmunodeficiencia de los Simios/metabolismo , Proteínas Reguladoras y Accesorias Virales/síntesis química
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