RESUMEN

BACKGROUND: In the phase 3 STELLAR trial, sotatercept, an investigational first-in-class activin signalling inhibitor, demonstrated beneficial effects on 6-min walk distance and additional efficacy endpoints in pre-treated participants with pulmonary arterial hypertension (PAH). METHODS: This post hoc analysis evaluated data from right heart catheterisation (RHC) and echocardiography (ECHO) obtained from the STELLAR trial. Changes from baseline in RHC and ECHO parameters were assessed at 24 weeks. An analysis of covariance (ANCOVA) model was used to estimate differences in least squares means with treatment and randomisation stratification (mono/double versus triple therapy; World Health Organization functional class II versus III) as fixed factors, and baseline value as covariate. RESULTS: Relative to placebo, treatment with sotatercept led to significant (all p<0.0001 except where noted) improvements from baseline in mean pulmonary artery (PA) pressure (-13.9 mmHg), pulmonary vascular resistance (-254.8 dyn·s·cm-5), mean right atrial pressure (-2.7 mmHg), mixed venous oxygen saturation (3.84%), PA elastance (-0.42 mmHg·mL-1·beat-1), PA compliance (0.58 mL·mmHg-1), cardiac efficiency (0.48 mL·beat-1·mmHg-1), right ventricular (RV) work (-0.85 g·m) and RV power (-32.70 mmHg·L·min-1). ECHO showed improvements in tricuspid annular plane systolic excursion (TAPSE) to systolic pulmonary artery pressure ratio (0.12 mm·mmHg-1), end-systolic and end-diastolic RV areas (-4.39 cm2 and -5.31 cm2, respectively), tricuspid regurgitation and RV fractional area change (2.04% p<0.050). No significant between-group changes from baseline were seen for TAPSE, heart rate, cardiac output, stroke volume or their indices. CONCLUSION: In pre-treated patients with PAH, sotatercept demonstrated substantial improvements in PA pressures, PA compliance, PA-RV coupling and right heart function.

Asunto(s)

Corazón , Hemodinámica , Humanos , Proteínas Recombinantes de Fusión/uso terapéutico , Cateterismo Cardíaco , Hipertensión Pulmonar Primaria Familiar

RESUMEN

Background: Data are limited regarding long-term consequences of invasive GBS (iGBS) disease in early infancy, especially from low- and middle-income countries (LMIC) where most cases occur. We aimed to estimate risk of neurodevelopmental impairment (NDI) in children with a history of iGBS disease. Methods: A multi-country matched cohort study was undertaken in South Africa, India, Mozambique, Kenya, and Argentina from October 2019 to April 2021. The exposure of interest was defined as a history of iGBS disease (sepsis or meningitis) before 90 days of age, amongst children now aged 1·5-18 years. Age and sex-matched, children without history of GBS were also recruited. Age-appropriate, culturally-adapted assessments were used to define NDI across multiple domains (cognitive, motor, hearing, vision, emotional-behaviour, growth). Pooled NDI risk was meta-analysed across sites. Association of iGBS exposure and NDI outcome was estimated using modified Poisson regression with robust variance estimator. Findings: Amongst 138 iGBS survivors and 390 non-iGBS children, 38·1% (95% confidence interval [CI]: 30·0% - 46·6%) of iGBS children had any NDI, compared to 21·7% (95% CI: 17·7% - 26·0%) of non- iGBS children, with notable between-site heterogeneity. Risk of moderate/severe NDI was 15·0% (95% CI: 3·4% - 30·8%) among GBS-meningitis, 5·6% (95% CI: 1·5% - 13·7%) for GBS-sepsis survivors. The adjusted risk ratio (aRR) for moderate/severe NDI among iGBS survivors was 1.27 (95% CI: 0.65, 2.45), when compared to non-GBS children. Mild impairment was more frequent in iGBS (27.6% (95% CI: 20.3 - 35.5%)) compared to non-GBS children (12.9% (95% CI: 9.7% - 16.4%)). The risk of emotional-behavioural problems was similar irrespective of iGBS exposure (aRR=0.98 (95% CI: 0.55, 1.77)). Interpretation: Our findings suggest that iGBS disease is on average associated with a higher risk of moderate/severe NDI, however substantial variation in risk was observed between sites and data are consistent with a wide range of values. Our study underlines the importance of long-term follow-up for at-risk neonates and more feasible, standardised assessments to facilitate diagnosis in research and clinical practice. Funding: This work was supported by a grant (INV-009018) from the Bill & Melinda Gates Foundation to the London School of Hygiene &Tropical Medicine.

Asunto(s)

COVID-19 , Enfermedades Reumáticas , Reumatología , COVID-19/epidemiología , Humanos , Pandemias , Enfermedades Reumáticas/epidemiología , SARS-CoV-2

RESUMEN

Numerous studies have focused on the need to expand production of 'blue foods', defined as aquatic foods captured or cultivated in marine and freshwater systems, to meet rising population- and income-driven demand. Here we analyze the roles of economic, demographic, and geographic factors and preferences in shaping blue food demand, using secondary data from FAO and The World Bank, parameters from published models, and case studies at national to sub-national scales. Our results show a weak cross-sectional relationship between per capita income and consumption globally when using an aggregate fish metric. Disaggregation by fish species group reveals distinct geographic patterns; for example, high consumption of freshwater fish in China and pelagic fish in Ghana and Peru where these fish are widely available, affordable, and traditionally eaten. We project a near doubling of global fish demand by mid-century assuming continued growth in aquaculture production and constant real prices for fish. Our study concludes that nutritional and environmental consequences of rising demand will depend on substitution among fish groups and other animal source foods in national diets.

Asunto(s)

Peces/crecimiento & desarrollo , Abastecimiento de Alimentos/estadística & datos numéricos , Alimentos , Renta/estadística & datos numéricos , Alimentos Marinos/estadística & datos numéricos , África , Animales , Acuicultura/métodos , Asia , Europa (Continente) , Abastecimiento de Alimentos/métodos , Agua Dulce , Geografía , Salud Global , Humanos , Modelos Teóricos , América del Norte , Alimentos Marinos/provisión & distribución , América del Sur

RESUMEN

BACKGROUND: The COVID-19 pandemic has disrupted the delivery of immunisation services globally. Many countries have postponed vaccination campaigns out of concern about infection risks to the staff delivering vaccination, the children being vaccinated, and their families. The World Health Organization recommends considering both the benefit of preventive campaigns and the risk of SARS-CoV-2 transmission when making decisions about campaigns during COVID-19 outbreaks, but there has been little quantification of the risks. METHODS: We modelled excess SARS-CoV-2 infection risk to vaccinators, vaccinees, and their caregivers resulting from vaccination campaigns delivered during a COVID-19 epidemic. Our model used population age structure and contact patterns from three exemplar countries (Burkina Faso, Ethiopia, and Brazil). It combined an existing compartmental transmission model of an underlying COVID-19 epidemic with a Reed-Frost model of SARS-CoV-2 infection risk to vaccinators and vaccinees. We explored how excess risk depends on key parameters governing SARS-CoV-2 transmissibility, and aspects of campaign delivery such as campaign duration, number of vaccinations, and effectiveness of personal protective equipment (PPE) and symptomatic screening. RESULTS: Infection risks differ considerably depending on the circumstances in which vaccination campaigns are conducted. A campaign conducted at the peak of a SARS-CoV-2 epidemic with high prevalence and without special infection mitigation measures could increase absolute infection risk by 32 to 45% for vaccinators and 0.3 to 0.5% for vaccinees and caregivers. However, these risks could be reduced to 3.6 to 5.3% and 0.1 to 0.2% respectively by use of PPE that reduces transmission by 90% (as might be achieved with N95 respirators or high-quality surgical masks) and symptomatic screening. CONCLUSIONS: SARS-CoV-2 infection risks to vaccinators, vaccinees, and caregivers during vaccination campaigns can be greatly reduced by adequate PPE, symptomatic screening, and appropriate campaign timing. Our results support the use of adequate risk mitigation measures for vaccination campaigns held during SARS-CoV-2 epidemics, rather than cancelling them entirely.

Asunto(s)

COVID-19/prevención & control , Brotes de Enfermedades/prevención & control , Personal de Salud , Programas de Inmunización/organización & administración , SARS-CoV-2 , Vacunación , Brasil , Burkina Faso , COVID-19/epidemiología , Niño , Etiopía , Femenino , Humanos , Masculino , Pandemias , Equipo de Protección Personal

RESUMEN

Sepsis and meningitis due to invasive group B Streptococcus (iGBS) disease during early infancy is a leading cause of child mortality. Recent systematic estimates of the worldwide burden of GBS suggested that there are 319,000 cases of infant iGBS disease each year, and an estimated 147,000 stillbirths and young-infant deaths, with the highest burden occurring in Sub-Saharan Africa.  The following priority data gaps were highlighted: (1) long-term outcome data after infant iGBS, including mild disability, to calculate quality-adjusted life years (QALYs) or disability-adjusted life years (DALYs) and (2) economic burden for iGBS survivors and their families. Geographic data gaps were also noted with few studies from low- and middle- income countries (LMIC), where the GBS burden is estimated to be the highest. In this paper we present the protocol for a multi-country matched cohort study designed to estimate the risk of long-term neurodevelopmental impairment (NDI), socioemotional behaviors, and economic outcomes for children who survive invasive GBS disease in Argentina, India, Kenya, Mozambique, and South Africa. Children will be identified from health demographic surveillance systems, hospital records, and among participants of previous epidemiological studies. The children will be aged between 18 months to 17 years. A tablet-based custom-designed application will be used to capture data from direct assessment of the child and interviews with the main caregiver. In addition, a parallel sub-study will prospectively measure the acute costs of hospitalization due to neonatal sepsis or meningitis, irrespective of underlying etiology. In summary, these data are necessary to characterize the consequences of iGBS disease and enable the advancement of effective strategies for survivors to reach their developmental and economic potential. In particular, our study will inform the development of a full public health value proposition on maternal GBS immunization that is being coordinated by the World Health Organization.

RESUMEN

The whitemouth croaker (Micropogonias furnieri) is one of the most commercially important species along the Atlantic coast of South America. Moreover, some of its biological traits (long life span, inshore feeding, high trophic position) make this species a suitable sentinel of coastal pollution. Here, we investigated contamination by multiple legacy and emerging organic pollutants, such as brominated and chlorinated flame retardants, polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs), in whitemouth croakers from two estuaries (Guanabara and Sepetiba Bays) located in industrialized and urbanized areas in Rio de Janeiro State, Southeastern Brazil. Furthermore, we assessed how biological and ecological features could explain the observed contamination patterns. Regarding brominated flame retardants, concentrations of polybrominated diphenyl ethers (PBDEs) varied from 7.6 to 879.7 pg g-1 wet weight (w.w.), with high contribution of tetra-, penta-, hexa- and deca-BDEs. The sum of chlorinated flame retardants (dechlorane-related compounds, ΣDRC) ranged from

Asunto(s)

Monitoreo del Ambiente , Perciformes/metabolismo , Contaminantes Químicos del Agua/metabolismo , Animales , Brasil , Dibenzofuranos Policlorados , Dioxinas , Retardadores de Llama , Éteres Difenilos Halogenados , Hidrocarburos Clorados , Dibenzodioxinas Policloradas , Compuestos Policíclicos

Asunto(s)

Humanos , Derivación Urinaria , Cálculos Urinarios

Asunto(s)

Cálculos Urinarios , Derivación Urinaria , Humanos

RESUMEN

An epidemic of post-surgical wound infections, caused by a non-tuberculous mycobacterium, has been on-going in Brazil. It has been unclear whether one or multiple lineages are responsible and whether their wide geographical distribution across Brazil is due to spread from a single point source or is the result of human-mediated transmission. 188 isolates, collected from nine Brazilian states, were whole genome sequenced and analysed using phylogenetic and comparative genomic approaches. The isolates from Brazil formed a single clade, which was estimated to have emerged in 2003. We observed temporal and geographic structure within the lineage that enabled us to infer the movement of sub-lineages across Brazil. The genome size of the Brazilian lineage was reduced relative to most strains in the three subspecies of Mycobacterium abscessus and contained a novel plasmid, pMAB02, in addition to the previously described pMAB01 plasmid. One lineage, which emerged just prior to the initial outbreak, is responsible for the epidemic of post-surgical wound infections in Brazil. Phylogenetic analysis indicates that multiple transmission events led to its spread. The presence of a novel plasmid and the reduced genome size suggest that the lineage has undergone adaptation to the surgical niche.

Asunto(s)

Brotes de Enfermedades , Infecciones por Mycobacterium no Tuberculosas/epidemiología , Infecciones por Mycobacterium no Tuberculosas/microbiología , Mycobacterium abscessus/genética , Infección de la Herida Quirúrgica/epidemiología , Infección de la Herida Quirúrgica/microbiología , Adaptación Biológica/genética , Técnicas de Tipificación Bacteriana , Brasil/epidemiología , Infección Hospitalaria , Transmisión de Enfermedad Infecciosa , Eliminación de Gen , Genes Bacterianos , Genómica , Humanos , Mycobacterium abscessus/clasificación , Mycobacterium abscessus/aislamiento & purificación , Fenotipo , Filogenia , Plásmidos/genética , Secuenciación Completa del Genoma

RESUMEN

Unraveling the physical and chemical properties of graphene-metal contacts is a key step toward the development of graphitic electronic nanodevices. Although many studies have revealed the way that various metals interact with graphene, few have described the structure and behavior of large pieces of graphene-metal nanostructures under different conditions. Here, we present the first classical molecular dynamics study of graphene-titanium (G-Ti) structures, with and without substrates. Physical and chemical properties of equilibrium structures of G-Ti interfaces with different amounts of titanium coverage are investigated. Adhesion of Ti films on graphene is shown to be enhanced by the vacancies in graphene or the electrostatic influence of substrates. The dynamics of pristine G-Ti structures at different temperatures on planar and nonplanar substrates are investigated, and the results show that G-Ti interfaces are thermally stable, that is, not prone to any reaction toward the formation of titanium carbide.

RESUMEN

BACKGROUND: The proximal tibia is one of the most challenging anatomic sites for extremity reconstructions after bone tumor resection. Because bone tumors are rare and large case series of reconstructions of the proximal tibia are lacking, we undertook this study to compare two major reconstructive approaches at two large sarcoma centers. QUESTIONS/PURPOSES: The purpose of this study was to compare groups of patients treated with endoprosthetic replacement or osteoarticular allograft reconstruction for proximal tibia bone tumors in terms of (1) limb salvage reconstruction failures and risk of amputation of the limb; (2) causes of failure; and (3) functional results. METHODS: Between 1990 and 2012, two oncologic centers treated 385 patients with proximal tibial resections and reconstruction. During that time, the general indications for those types of reconstruction were proximal tibia malignant tumors or bone destruction with articular surface damage or collapse. Patients who matched the inclusion criteria (age between 15 and 60 years old, diagnosis of a primary bone tumor of the proximal tibia treated with limb salvage surgery and reconstructed with endoprosthetic replacement or osteoarticular allograft) were included for analysis (n = 149). In those groups (endoprosthetic or allograft), of the patients not known to have reached an endpoint (death, reconstructive failure, or limb loss) before 2 years, 85% (88 of 104) and 100% (45 of 45) were available for followup at a minimum of 2 years. A total of 88 patients were included in the endoprosthetic group and 45 patients in the osteoarticular allograft group. Followup was at a mean of 9.5 (SD 6.72) years (range, 2-24 years) for patients with endoprosthetic reconstructions, and 7.4 (SD 5.94) years for patients treated with allografts (range, 2-21 years). The following variables were compared: limb salvage reconstruction failure rates, risk of limb amputation, type of failures according to the Henderson et al. classification, and functional results assessed by the Musculoskeletal Tumor Society system. RESULTS: With the numbers available, after competitive risk analysis, the probability of failure for endoprosthetic replacement of the proximal tibia was 18% (95% confidence interval [CI], 10.75-27.46) at 5 years and 44% (95% CI, 31.67-55.62) at 10 years and for osteoarticular allograft reconstruction was 27% (95% CI, 14.73-40.16) at 5 years and 32% (95% CI, 18.65-46.18) at 10 years. There were no differences in terms of risk of failures at 5 years (p = 0.26) or 10 years (p = 0.20) between the two groups. Fifty-one of 88 patients (58%) with proximal tibia endoprostheses developed a reconstruction failure with mechanical causes being the most prevalent (32 of 51 patients [63%]). A total of 19 of 45 osteoarticular allograft reconstructions failed (42%) and nine of 19 (47%) of them were caused by early infection. Ten-year risk of amputation after failure for endoprosthetic reconstruction was 10% (95% CI, 5.13-18.12) and 11% (95% CI, 4.01-22.28) for osteoarticular allograft with no difference between the groups (p = 0.91). With the numbers available, there were no differences between the groups in terms of the mean Musculoskeletal Tumor Society score (26.58, SD 2.99, range, 19-30 versus 27.52, SD 1.91, range, 22-30; p = 0.13; 95% CI, -2,3 to 0.32). Mean extension lag was more severe in the endoprosthetic group than the osteoarticular allograft group: 13.56° (SD 18.73; range, 0°-80°) versus 2.41° (SD 5.76; range, 0°-30°; p < 0.001; 95% CI, 5.8-16.4). CONCLUSIONS: Reconstruction of the proximal tibia with either endoprosthetic replacement or osteoarticular allograft appears to offer similar reconstruction failures rates. The primary cause of failure for allograft was infection and for endoprosthesis was mechanical complications. We believe that the treating surgeon should have both options available for treatment of patients with malignant or aggressive tumors of the proximal tibia. (S)he might consider an allograft in a younger patient to achieve better extensor mechanism function, whereas in an older patient or one with a poorer prognosis where return to function and ambulation quickly is desired, an endoprosthesis may be advantageous. LEVEL OF EVIDENCE: Level III, therapeutic study.

Asunto(s)

Artroplastia de Reemplazo de Rodilla/instrumentación , Neoplasias Óseas/cirugía , Trasplante Óseo/métodos , Prótesis de la Rodilla , Osteotomía , Tibia/cirugía , Adolescente , Adulto , Amputación Quirúrgica , Argentina , Artroplastia de Reemplazo de Rodilla/efectos adversos , Neoplasias Óseas/diagnóstico por imagen , Neoplasias Óseas/patología , Trasplante Óseo/efectos adversos , Bases de Datos Factuales , Inglaterra , Femenino , Humanos , Recuperación del Miembro , Masculino , Persona de Mediana Edad , Osteotomía/efectos adversos , Complicaciones Posoperatorias/etiología , Complicaciones Posoperatorias/cirugía , Diseño de Prótesis , Reoperación , Estudios Retrospectivos , Factores de Riesgo , Tibia/diagnóstico por imagen , Tibia/patología , Factores de Tiempo , Trasplante Homólogo , Resultado del Tratamiento , Adulto Joven

Asunto(s)

Sordera , Enfermedades Mitocondriales , ADN Mitocondrial , Diabetes Mellitus , Diabetes Mellitus Tipo 2 , Humanos , Linaje

RESUMEN

Modern strains of Mycobacterium tuberculosis from the Americas are closely related to those from Europe, supporting the assumption that human tuberculosis was introduced post-contact. This notion, however, is incompatible with archaeological evidence of pre-contact tuberculosis in the New World. Comparative genomics of modern isolates suggests that M. tuberculosis attained its worldwide distribution following human dispersals out of Africa during the Pleistocene epoch, although this has yet to be confirmed with ancient calibration points. Here we present three 1,000-year-old mycobacterial genomes from Peruvian human skeletons, revealing that a member of the M. tuberculosis complex caused human disease before contact. The ancient strains are distinct from known human-adapted forms and are most closely related to those adapted to seals and sea lions. Two independent dating approaches suggest a most recent common ancestor for the M. tuberculosis complex less than 6,000 years ago, which supports a Holocene dispersal of the disease. Our results implicate sea mammals as having played a role in transmitting the disease to humans across the ocean.

Asunto(s)

Caniformia/microbiología , Genoma Bacteriano/genética , Mycobacterium tuberculosis/genética , Tuberculosis/historia , Tuberculosis/microbiología , Zoonosis/historia , Zoonosis/microbiología , Animales , Huesos/microbiología , Europa (Continente)/etnología , Genómica , Historia Antigua , Migración Humana/historia , Humanos , Perú , Filogenia , Tuberculosis/transmisión , Zoonosis/transmisión

RESUMEN

The impacts of oocyte parasites on the reproductive success of molluscs are largely unknown. In this study, we evaluated the presence of gonad parasites in 6 species of marine bivalve molluscs native to southern Brazil. Cultured bivalves included the mangrove oyster Crassostrea gasar (sometimes called C. brasiliana), the brown mussel Perna perna, the lion's paw scallop Nodipecten nodosus and the wing pearl oyster Pteria hirundo. Another species of mangrove oyster, C. rhizophorae, and the carib pointed venus clam Anomalocardia brasiliana (syn. A. flexuosa) were collected from the wild. Molluscs were collected in winter 2009 and summer 2010 for histopathological and molecular evaluation. An unknown ovarian parasite (UOP) was observed in histopathological sections of female gonads of C. gasar and C. rhizophorae. The UOP possessed features suggestive of amoebae, including an irregular outer membrane, frothy cytoplasm, a nucleus with a prominent central nucleolus and a closely associated basophilic parasome. PCR analysis was negative for Marteilioides chungmuensis, Perkinsus spp. and Paramoeba perurans. However, real-time PCR successfully amplified DNA from oyster gonads when using universal Paramoeba spp. primers. Also, conventional PCR amplified DNA using primers specific for Perkinsela amoebae-like organisms (syn. Perkinsiella), which are considered as endosymbionts of Parameoba spp., previously thought to be the parasome. Our results suggest that this UOP is a species of amoeba belonging to 1 of the 2 families of the order Dactylopodida, possibly related to Paramoeba spp. This study represents the first report of this type of organism in oysters. We found that C. gasar and C. rhizophorae were the most susceptible molluscs to these UOPs.

Asunto(s)

Amebozoos/aislamiento & purificación , Crassostrea/parasitología , Gónadas/parasitología , Animales , Brasil , Interacciones Huésped-Parásitos

RESUMEN

Lead was ubiquitous on Caribbean sugar plantations, where it was used extensively in the production of sugar and rum. Previous studies suggest that skeletal lead contents can be used to identify African-born individuals (as opposed to Creoles) among slave burials found in the New World. To test this hypothesis, we measured lead concentrations in enamel samples from 26 individuals from the Newton Plantation cemetery in Barbados, which was in use from around 1660 to 1820, and compared the results with enamel (87) Sr/(86) Sr measurements that had been previously obtained for the same population. Results show a clear association between low (i.e., below 1 ppm) enamel lead concentrations and higher enamel (87) Sr/(86) Sr ratios which have previously been interpreted as being indicative of African birth, suggesting that individuals with low enamel lead levels were indeed born in Africa as opposed to the New World. Based on these results, we propose that enamel lead measurements provide an effective and inexpensive way to determine African birth from skeletal remains. Furthermore, the lead measurements can provide useful insights into the health status and childhood environment of enslaved Africans during the colonial period.

Asunto(s)

Población Negra/estadística & datos numéricos , Intoxicación por Plomo/epidemiología , Problemas Sociales/estadística & datos numéricos , Adolescente , Adulto , África/etnología , Factores de Edad , Anciano , Antropología Física , Barbados/epidemiología , Niño , Preescolar , Esmalte Dental/química , Emigrantes e Inmigrantes/historia , Emigrantes e Inmigrantes/estadística & datos numéricos , Femenino , Estado de Salud , Historia del Siglo XVII , Historia del Siglo XVIII , Historia del Siglo XIX , Humanos , Masculino , Persona de Mediana Edad , Problemas Sociales/etnología

RESUMEN

There are several models of decomposition of the electrocardiogram (ECG). Some of these models are intended to describe the ECG signal, and others are more specific to extract the relevant information relating to individual waveform which contributes to explain the P-QRS complex. The latter approach may be particularly suitable for a portion where a morphological analysis of the ECG is of particular interest, as the cardiac repolarization segment or T-wave. This study aims: to model and detect useful patterns in the evaluation of T wave morphology, which explains the different changes in ventricular repolarization during inhalation of Salbutamol.

Asunto(s)

Antagonistas Adrenérgicos beta/uso terapéutico , Albuterol/uso terapéutico , Electrocardiografía/instrumentación , Enfermedades del Sistema Nervioso Periférico/tratamiento farmacológico , Humanos , Modelos Teóricos , Enfermedades del Sistema Nervioso Periférico/fisiopatología

RESUMEN

Vibrio cholerae is a globally important pathogen that is endemic in many areas of the world and causes 3-5 million reported cases of cholera every year. Historically, there have been seven acknowledged cholera pandemics; recent outbreaks in Zimbabwe and Haiti are included in the seventh and ongoing pandemic. Only isolates in serogroup O1 (consisting of two biotypes known as 'classical' and 'El Tor') and the derivative O139 can cause epidemic cholera. It is believed that the first six cholera pandemics were caused by the classical biotype, but El Tor has subsequently spread globally and replaced the classical biotype in the current pandemic. Detailed molecular epidemiological mapping of cholera has been compromised by a reliance on sub-genomic regions such as mobile elements to infer relationships, making El Tor isolates associated with the seventh pandemic seem superficially diverse. To understand the underlying phylogeny of the lineage responsible for the current pandemic, we identified high-resolution markers (single nucleotide polymorphisms; SNPs) in 154 whole-genome sequences of globally and temporally representative V. cholerae isolates. Using this phylogeny, we show here that the seventh pandemic has spread from the Bay of Bengal in at least three independent but overlapping waves with a common ancestor in the 1950s, and identify several transcontinental transmission events. Additionally, we show how the acquisition of the SXT family of antibiotic resistance elements has shaped pandemic spread, and show that this family was first acquired at least ten years before its discovery in V. cholerae.

Asunto(s)

Cólera/epidemiología , Cólera/transmisión , Pandemias/estadística & datos numéricos , Vibrio cholerae/genética , Vibrio cholerae/aislamiento & purificación , Cólera/microbiología , Genoma Bacteriano/genética , Haití/epidemiología , Humanos , Funciones de Verosimilitud , Epidemiología Molecular , Filogenia , Polimorfismo de Nucleótido Simple/genética , Vibrio cholerae/clasificación , Zimbabwe/epidemiología

RESUMEN

Current methods for differentiating isolates of predominant lineages of pathogenic bacteria often do not provide sufficient resolution to define precise relationships. Here, we describe a high-throughput genomics approach that provides a high-resolution view of the epidemiology and microevolution of a dominant strain of methicillin-resistant Staphylococcus aureus (MRSA). This approach reveals the global geographic structure within the lineage, its intercontinental transmission through four decades, and the potential to trace person-to-person transmission within a hospital environment. The ability to interrogate and resolve bacterial populations is applicable to a range of infectious diseases, as well as microbial ecology.

Asunto(s)

Infección Hospitalaria/microbiología , Genoma Bacteriano , Staphylococcus aureus Resistente a Meticilina/clasificación , Staphylococcus aureus Resistente a Meticilina/genética , Infecciones Estafilocócicas/microbiología , Asia/epidemiología , Técnicas de Tipificación Bacteriana , Infección Hospitalaria/epidemiología , Infección Hospitalaria/transmisión , Europa (Continente)/epidemiología , Evolución Molecular , Genómica/métodos , Humanos , Funciones de Verosimilitud , Staphylococcus aureus Resistente a Meticilina/aislamiento & purificación , Epidemiología Molecular , Datos de Secuencia Molecular , Filogenia , Polimorfismo de Nucleótido Simple , Análisis de Secuencia de ADN , América del Sur/epidemiología , Infecciones Estafilocócicas/epidemiología , Infecciones Estafilocócicas/transmisión , Factores de Tiempo , Estados Unidos/epidemiología

RESUMEN

Autonomic neuropathy (AN) is a common and serious complication of diabetes. Early detection is essential to enable appropriate interventional therapy. It has long been recognized that subjects with diabetic peripheral neuropathy (DPN) are at much greater risk of developing AN, but there is currently no simple screening tool to assess them. The aim of this study was to investigate pupil responsiveness in diabetic subjects with and without DPN using dynamic pupillometry. During the first test, one flash was administered and the pupil response recorded for 3 seconds. In the second test, twenty-five flashes at one-second intervals were administered and the pupil response recorded for 30 seconds. Several time related parameters were computed from the results. A total of 29 diabetic subjects (17 no DPN, 12 DPN) and 25 healthy volunteers took part in the study. In the first test, pupil-iris ratios in darkness, large deviation and plateau were significantly different between groups. Latency time from flash exposure to the start of constriction was significantly longer in diabetic subjects with DPN compared to healthy volunteers. There was no difference in latency times of largest deviation, plateau or duration of constriction between groups. In the second test, the pupil-iris ratios evaluated in the frame preceding the tenth and the twenty-fifth light flash were significantly greater in healthy volunteers than diabetic subjects with DPN. Latency time from the tenth and twenty-fifth flash exposure to the start of constriction was significantly shorter in healthy volunteers than in diabetic subjects with DPN.

Asunto(s)

Adaptación Ocular , Neuropatías Diabéticas/diagnóstico , Neuropatías Diabéticas/fisiopatología , Luz , Pupila , Reflejo Pupilar , Diagnóstico Diferencial , Femenino , Humanos , Masculino , Valor Predictivo de las Pruebas , Factores de Tiempo