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BACKGROUND: Leptospirosis is an underdiagnosed infectious disease with non-specific clinical presentation that requires laboratory confirmation for diagnosis. The serologic reference standard remains the microscopic agglutination test (MAT) on paired serum samples. However, reported estimates of MAT's sensitivity vary. We evaluated the accuracy of four index tests, MAT on paired samples as well as alternative standards for leptospirosis diagnosis: MAT on single acute-phase samples, polymerase chain reaction (PCR) with the target gene Lfb1, and ELISA IgM with Leptospira fainei serovar Hurstbridge as an antigen. METHODS: We performed a systematic review of studies reporting results of leptospirosis diagnostic tests. We searched eight electronic databases and selected studies that tested human blood samples and compared index tests with blood culture and/or PCR and/or MAT (comparator tests). For MAT selection criteria we defined a threshold for single acute-phase samples according to a national classification of leptospirosis endemicity. We used a Bayesian random-effect meta-analysis to estimate the sensitivity and specificity of MAT in single acute-phase and paired samples separately, and assessed risk of bias using the Quality Assessment of Studies of Diagnostic Accuracy Approach- 2 (QUADAS-2) tool. RESULTS: For the MAT accuracy evaluation, 15 studies were included, 11 with single acute-phase serum, and 12 with paired sera. Two included studies used PCR targeting the Lfb1 gene, and one included study used IgM ELISA with Leptospira fainei serovar Hurstbridge as antigen. For MAT in single acute-phase samples, the pooled sensitivity and specificity were 14% (95% credible interval [CrI] 3-38%) and 86% (95% CrI 59-96%), respectively, and the predicted sensitivity and specificity were 14% (95% CrI 0-90%) and 86% (95% CrI 9-100%). Among paired MAT samples, the pooled sensitivity and specificity were 68% (95% CrI 32-92%) and 75% (95% CrI 45-93%) respectively, and the predicted sensitivity and specificity were 69% (95% CrI 2-100%) and 75% (2-100%). CONCLUSIONS: Based on our analysis, the accuracy of MAT in paired samples was not high, but it remains the reference standard until a more accurate diagnostic test is developed. Future studies that include larger numbers of participants with paired samples will improve the certainty of accuracy estimates.
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Leptospira , Leptospirosis , Humanos , Serogrupo , Teorema de Bayes , Anticuerpos Antibacterianos , Pruebas de Aglutinación/métodos , Sensibilidad y Especificidad , Ensayo de Inmunoadsorción Enzimática/métodos , Inmunoglobulina M , Reacción en Cadena de la PolimerasaRESUMEN
Determining the appropriate technique for diastema closure is challenging, and the decision must be evidence based. The objective of these case reports is to describe different approaches to diastema closure using direct and indirect techniques, focusing on the characteristics of the patient and clinical requirements to guide treatment. In the first case, a 16-year-old patient had multiple diastemas in the maxillary anterior dentition. The clinical evaluation revealed microdontia of the lateral incisors and malpositioned teeth. The treatment included tooth whitening and placement of composite resin veneers using a direct technique. In the second case, a 54-year-old patient displayed a disharmonious and esthetically compromised smile due to small teeth, color changes, multiple diastemas, incisal wear, and severe dentogingival disproportion. Based on the patient's expectations, the patient's age, and the presence of a "black triangle" interdental space, a multidisciplinary restorative treatment was proposed, including gingivoplasty, tooth whitening, and placement of ceramic laminate veneers using an indirect technique. Both approaches achieved successful esthetic rehabilitation and diastema closure with minimal intervention. The choice of procedure and restorative material, as well as the need for tooth preparation, varied based on the clinical requirements, patient expectations, and financial constraints. Careful treatment planning avoided lengthy and inefficient procedures.
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Diastema , Maloclusión , Humanos , Adolescente , Persona de Mediana Edad , Diastema/terapia , Estética Dental , Coronas con Frente Estético , Cerámica , Resinas Compuestas/uso terapéuticoRESUMEN
BACKGROUND: Lower respiratory tract infections are a leading cause of death in young children, but few studies have collected the specimens needed to define the role of specific causes. The Child Health and Mortality Prevention Surveillance (CHAMPS) platform aims to investigate causes of death in children aged <5 years in high-mortality rate settings, using postmortem minimally invasive tissue sampling and other advanced diagnostic techniques. We examined findings for deaths identified in CHAMPS sites in 7 countries in sub-Saharan Africa and south Asia to evaluate the role of respiratory syncytial virus (RSV). METHODS: We included deaths that occurred between December 2016 and December 2019. Panels determined causes of deaths by reviewing all available data including pathological results from minimally invasive tissue sampling, polymerase chain reaction screening for multiple infectious pathogens in lung tissue, nasopharyngeal swab, blood, and cerebrospinal fluid samples, clinical information from medical records, and verbal autopsies. RESULTS: We evaluated 1213 deaths, including 695 in neonates (aged <28 days), 283 in infants (28 days to <12 months), and 235 in children (12-59 months). RSV was detected in postmortem specimens in 67 of 1213 deaths (5.5%); in 24 deaths (2.0% of total), RSV was determined to be a cause of death, and it contributed to 5 other deaths. Younger infants (28 days to <6 months of age) accounted for half of all deaths attributed to RSV; 6.5% of all deaths in younger infants were attributed to RSV. RSV was the underlying and only cause in 4 deaths; the remainder (nâ =â 20) had a median of 2 (range, 1-5) other conditions in the causal chain. Birth defects (nâ =â 8) and infections with other pathogens (nâ =â 17) were common comorbid conditions. CONCLUSIONS: RSV is an important cause of child deaths, particularly in young infants. These findings add to the substantial body of literature calling for better treatment and prevention options for RSV in high-mortality rate settings.
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Infecciones por Virus Sincitial Respiratorio , Virus Sincitial Respiratorio Humano , Infecciones del Sistema Respiratorio , Niño , Salud Infantil , Mortalidad del Niño , Preescolar , Humanos , Lactante , Recién Nacido , Infecciones por Virus Sincitial Respiratorio/epidemiología , Infecciones por Virus Sincitial Respiratorio/prevención & control , Infecciones del Sistema Respiratorio/epidemiologíaRESUMEN
UNLABELLED: Increasing recent evidence favors paracetamol use for patent ductus arteriosus (PDA) closure in preterms. Our study aims were (1) to assess efficacy and safety of intravenous (i.v.) paracetamol for PDA closure in a 23-32-week preterm population, as "first-line" (when traditional ibuprofen treatment was contraindicated) or "rescue" treatment (after ibuprofen failed), and (2) to identify predictors of PDA closure. The cumulative efficacy of consecutive cycles of i.v. paracetamol on PDA closure was confirmed after both "first-line" and "rescue" treatment, the overall PDA closure rates being, respectively, 56.7 and 61.1 % (p = 0.7624) after two cycles and 63.3 and 77.8 % (p = 0.2959) after three cycles. No toxicity was apparent after either "first-line" or "rescue" i.v. paracetamol treatment. On multivariate analysis, gestational age (GA) emerged as an independent predictor of PDA closure in the "first-line" i.v. paracetamol treatment group, while clinical risk index for babies (CRIB) score (a patient risk index based on birth weight, GA at birth, sex, patient's temperature on admission, and maximum base excess in first 12 h of life) was an independent predictor of PDA closure failure in the "rescue" group. CONCLUSION: I.V. paracetamol proved effective in our study population. Randomized control trials (RCTs) are warranted to further investigate the efficacy and safety of i.v. paracetamol for PDA closure in preterms. WHAT IS KNOWN: ⢠Oral paracetamol has been judged as effective as oral ibuprofen for PDA closure in the preterm. ⢠To date, only a handful of non-randomized studies exist to support the effectiveness of i.v. paracetamol in PDA closure. What is New: ⢠Our observations confirm the clinical efficacy of i.v. paracetamol for PDA closure in a very low birth weight (VLBW)/extremely low birth weight (ELBW) preterm population. ⢠Gestational age and CRIB score emerge as independent predictors of PDA closure.
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Acetaminofén/administración & dosificación , Inhibidores de la Ciclooxigenasa/administración & dosificación , Conducto Arterioso Permeable/tratamiento farmacológico , Ibuprofeno/administración & dosificación , Administración Intravenosa , Conducto Arterioso Permeable/diagnóstico por imagen , Ecocardiografía , Femenino , Edad Gestacional , Humanos , Recien Nacido con Peso al Nacer Extremadamente Bajo , Recién Nacido , Recien Nacido Prematuro , Modelos Logísticos , Estudios Longitudinales , Masculino , Estudios ProspectivosAsunto(s)
Cambio Climático , Estado de Salud , Niño , Protección a la Infancia , Salud Global , Humanos , PobrezaRESUMEN
OBJECTIVES: We tested the hypothesis that adjunctive rosiglitazone treatment would reduce levels of circulating angiopoietin-2 (Angpt-2) and improve outcomes of Mozambican children with severe malaria. METHODS: A randomized, double-blind, placebo-controlled trial of rosiglitazone vs placebo as adjunctive treatment to artesunate in children with severe malaria was conducted. A 0.045 mg/kg/dose of rosiglitazone or matching placebo were administered, in addition to standard of malaria care, twice a day for 4 days. The primary endpoint was the rate of decline of Angpt-2 over 96 hours. Secondary outcomes included the longitudinal dynamics of angiopoietin-1 (Angpt-1) and the Angpt-2/Angpt-1 ratio over 96 hours, parasite clearance kinetics, clinical outcomes, and safety metrics. RESULTS: Overall, 180 children were enrolled; 91 were assigned to rosiglitazone and 89 to placebo. Children who received rosiglitazone had a steeper rate of decline of Angpt-2 over the first 96 hours of hospitalization compared to children who received placebo; however, the trend was not significant (P = 0.28). A similar non-significant trend was observed for Angpt-1 (P = 0.65) and the Angpt-2/Angpt-1 ratio (P = 0.34). All other secondary and safety outcomes were similar between groups (P >0.05). CONCLUSION: Adjunctive rosiglitazone at this dosage was safe and well tolerated but did not significantly affect the longitudinal kinetics of circulating Angpt-2.
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Antimaláricos , Malaria Falciparum , Malaria , Humanos , Niño , Rosiglitazona/uso terapéutico , Mozambique , Malaria/tratamiento farmacológico , Artesunato/uso terapéutico , Método Doble Ciego , Malaria Falciparum/tratamiento farmacológico , Antimaláricos/efectos adversosRESUMEN
Introduction: The progressive loss of skeletal muscle mass, strength, and function that frequently occurs as people get older is referred to as sarcopenia. Elderly musculoskeletal aging, sarcopenia, and obesity are all intimately connected. Our study's aim is to investigate the prevalence of sarcopenia in a real cohort of patients over 65 with musculoskeletal conditions referring to a Rehabilitation Unit. The secondary aim of our study is to investigate associations between sarcopenia and alterations in nutritional status and Body Mass Index (BMI). Finally, quality of life and global health has been investigated in our population. Materials and methods: From January 2019 to January 2021, 247 patients over 65 years old with musculoskeletal concerns were enrolled and participated in an observational study. As outcome measures, the Mini Nutritional Assessment (MNA), the 12-Item Short Form Health Survey (SF-12), and the Cumulative Illness Rating Scale Severity Index (CIRS-SI) were used. Additionally, measurements of total skeletal muscle mass (SMM) and appendicular muscle mass (ASMM) using bioelectrical impedance analysis, as well as a hand grip strength test of the non-dominant hand were taken. The Mid Upper Arm Circumference (MUAC) and the Calf Circumference (CC) were measured and recorded as further indications of possible sarcopenia. Results: A percentage of 46.1% of subjects with overt sarcopenia was found and 10.1% showed a severe sarcopenia. Patients with severe sarcopenia showed significantly lower values of BMI and MNA. Additionally, sarcopenic patients showed significantly lower values in MNA when compared to non-sarcopenic patients. Considering SF-12, only the physical score revealed slight significant differences. In particular, patients affected by probable or severe sarcopenia presented a lower value than non-sarcopenic patients. Concerning MUAC and CC, severe sarcopenic patients showed significant lower values for both the body parts. Conclusion: Our study considers a cohort of real-life elderly subjects with musculoskeletal concerns and shows that these subjects are highly susceptible to sarcopenia. Therefore, rehabilitation for elderly patients with musculoskeletal concerns requires to be customized and multidisciplinary. Future research should further investigate these aspects in order to enable the early identification of sarcopenia and the formulation of customized rehabilitative programs. .
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Estado Nutricional , Sarcopenia , Anciano , Humanos , Sarcopenia/epidemiología , Fuerza de la Mano , Prevalencia , Calidad de VidaRESUMEN
BACKGROUND: Spinal muscular atrophy (SMA) is caused by bi-allelic, recessive mutations of the survival motor neuron 1 (SMN1) gene and reduced expression levels of the survival motor neuron (SMN) protein. Degeneration of alpha motor neurons in the spinal cord causes progressive skeletal muscle weakness. The wide range of disease severities, variable rates of decline, and heterogenous clinical responses to approved disease-modifying treatment remain poorly understood and limit the ability to optimize treatment for patients. Validation of a reliable biomarker(s) with the potential to support early diagnosis, inform disease prognosis and therapeutic suitability, and/or confirm response to treatment(s) represents a significant unmet need in SMA. OBJECTIVES: The SMA Multidisciplinary Biomarkers Working Group, comprising 11 experts in a variety of relevant fields, sought to determine the most promising candidate biomarker currently available, determine key knowledge gaps, and recommend next steps toward validating that biomarker for SMA. METHODS: The Working Group engaged in a modified Delphi process to answer questions about candidate SMA biomarkers. Members participated in six rounds of reiterative surveys that were designed to build upon previous discussions. RESULTS: The Working Group reached a consensus that neurofilament (NF) is the candidate biomarker best poised for further development. Several important knowledge gaps were identified, and the next steps toward filling these gaps were proposed. CONCLUSIONS: NF is a promising SMA biomarker with the potential for prognostic, predictive, and pharmacodynamic capabilities. The Working Group has identified needed information to continue efforts toward the validation of NF as a biomarker for SMA.
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Atrofia Muscular Espinal , Humanos , Atrofia Muscular Espinal/diagnóstico , Atrofia Muscular Espinal/genética , Atrofia Muscular Espinal/tratamiento farmacológico , Neuronas Motoras/metabolismo , Biomarcadores/metabolismo , MutaciónRESUMEN
The Manhiça Health Research Centre (Manhiça HDSS) was established in 1996 in Manhiça, a rural district at Maputo Province in the southern part of Mozambique with approximately 49,000 inhabited households, a total population of 209.000 individuals, and an annual estimated birth cohort of about 5000 babies. Since 2016, Manhiça HDSS is implementing the Child Health and Mortality Prevention Surveillance (CHAMPS) program aiming to investigate causes of death (CoD) in stillbirths and children under the age of 5 years using an innovative post-mortem technique known as Minimally Invasive Tissue sampling (MITS), comprehensive pathogen screening using molecular methods, clinical record abstraction and verbal autopsy. Both in-hospital and community pediatric deaths are investigated using MITS. For this, community-wide socio-demographic approaches (notification of community deaths by key informants, formative research involving several segments of the community, availability of free phone lines for notification of medical emergencies and deaths, etc.) are conducted alongside to foster community awareness, involvement and adherence as well as to compute mortality estimates and collect relevant information of health and mortality determinants. The main objective of this paper is to describe the Manhiça Health and Demographic Surveillance System (HDSS) site and the CHAMPS research environment in place including the local capacities among its reference hospital, laboratories, data center and other relevant areas involved in this ambitious surveillance and research project, whose ultimate aim is to improve child survival through public health actions derived from credible estimates and understanding of the major causes of childhood mortality in Mozambique.
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Causas de Muerte , Salud Infantil , Mortalidad del Niño , Humanos , Mozambique/epidemiología , Mortalidad del Niño/tendencias , Preescolar , Lactante , Vigilancia de la Población/métodos , Femenino , Recién Nacido , Masculino , Población Rural/estadística & datos numéricos , Niño , Mortinato/epidemiologíaRESUMEN
BACKGROUND: Nusinersen is approved for the treatment of spinal muscular atrophy. The most common approved dosing regimen is four intrathecal loading doses of nusinersen 12 mg; the first three are administered at 14-day intervals followed by a fourth dose 30 days later, and then 12-mg maintenance doses are administered every 4 months thereafter. Interruption of nusinersen treatment in the maintenance dosing phase might occur for a number of clinical reasons. OBJECTIVE: The objective of this report is to describe dosing regimens that allow for the most rapid restoration of steady-state concentrations of nusinersen in the cerebrospinal fluid (CSF) following a treatment interruption during maintenance dosing. METHODS: Population pharmacokinetic models using integrated pharmacokinetic data from ten nusinersen clinical trials that included a broad range of participants with spinal muscular atrophy treated with intrathecal nusinersen were used to investigate different durations of treatment interruptions during maintenance treatment. Potential dosing regimens for re-initiation of nusinersen were evaluated, with the goal of achieving the quickest restoration of steady-state nusinersen CSF concentrations without exceeding maximal CSF exposures observed during the initial loading period. RESULTS: Our pharmacokinetic modeling indicates the following regimen will lead to optimal restoration of nusinersen CSF levels after treatment interruption: two doses of nusinersen should be administered at 14-day intervals following treatment interruptions of ≥ 8 to < 16 months since the last dose, and three doses of nusinersen at 14-day intervals for treatment interruptions of ≥ 16 to < 40 months since the last maintenance dose, with subsequent maintenance dosing every 4 months in both instances. After treatment interruptions of ≥ 40 months, the full loading regimen will rapidly restore nusinersen CSF levels. CONCLUSIONS: Prolonged treatment interruptions lead to suboptimal CSF levels of nusinersen. The optimal regimen to restore nusinersen CSF levels depends on the interval since the last maintenance dose was administered.
Nusinersen is a drug used to treat people of all ages who have spinal muscular atrophy. Nusinersen is injected with a thin needle into the lower back, a procedure known as a lumbar puncture. People initially receive three doses of nusinersen 12 mg each 14 days apart. They receive a fourth dose 1 month later, and then injections every 4 months (known as maintenance dosing). This treatment plan allows nusinersen to build up to effective levels in the fluid surrounding the spinal cord and brain. Some people may miss dose(s) or may stop nusinersen treatment at some point during maintenance dosing and then may want to continue treatment. This study used information from ten clinical trials to find out the best way to restart treatment to build up nusinersen to effective levels. People with a treatment break of ≥ 8 to < 16 months since the last dose need two doses of nusinersen at 14-day intervals before receiving maintenance dosing. People with a treatment break of ≥ 16 to < 40 months since the last dose need three doses of nusinersen at 14-day intervals before receiving maintenance dosing. If people stopped treatment for ≥ 40 months, they would need four doses before starting maintenance treatment. Results from this study showed that the number of doses that people needed before starting maintenance treatment depended on how long the treatment break was.
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Relación Dosis-Respuesta a Droga , Monitoreo de Drogas/métodos , Quimioterapia de Mantención/métodos , Atrofia Muscular Espinal , Oligonucleótidos , Esquema de Medicación , Duración de la Terapia , Humanos , Inyecciones Espinales/métodos , Modelos Biológicos , Atrofia Muscular Espinal/líquido cefalorraquídeo , Atrofia Muscular Espinal/tratamiento farmacológico , Oligonucleótidos/administración & dosificación , Oligonucleótidos/líquido cefalorraquídeo , Oligonucleótidos/farmacocinética , Oligonucleótidos Antisentido/administración & dosificación , Oligonucleótidos Antisentido/líquido cefalorraquídeo , Oligonucleótidos Antisentido/farmacocinética , Resultado del TratamientoRESUMEN
Lung ultrasound (LUS) is a promising point-of-care imaging technology for diagnosing and managing pneumonia. We sought to explore serial LUS examinations in children with chest-indrawing pneumonia in resource-constrained settings and compare their clinical and LUS imaging courses longitudinally. We conducted a prospective, observational study among children aged 2 through 23 months with World Health Organization Integrated Management of Childhood Illness chest-indrawing pneumonia and among children without fast breathing, chest indrawing or fever (no pneumonia cohort) at 2 district hospitals in Mozambique and Pakistan. We assessed serial LUS at enrollment, 2, 6, and 14 days, and performed a secondary analysis of enrolled children's longitudinal clinical and imaging courses. By Day 14, the majority of children with chest-indrawing pneumonia and consolidation on enrollment LUS showed improvement on follow-up LUS (100% in Mozambique, 85.4% in Pakistan) and were clinically cured (100% in Mozambique, 78.0% in Pakistan). In our cohort of children with chest-indrawing pneumonia, LUS imaging often reflected the clinical course; however, it is unclear how serial LUS would inform the routine management of non-severe chest-indrawing pneumonia.
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Pulmón/diagnóstico por imagen , Neumonía/diagnóstico por imagen , Neumonía/epidemiología , Pruebas en el Punto de Atención , Tórax/diagnóstico por imagen , Femenino , Estudios de Seguimiento , Humanos , Lactante , Estudios Longitudinales , Masculino , Mozambique/epidemiología , Pakistán/epidemiología , Proyectos Piloto , Estudios Prospectivos , Ultrasonografía/métodosRESUMEN
OBJECTIVE: Improved pneumonia diagnostics are needed, particularly in resource-constrained settings. Lung ultrasound (LUS) is a promising point-of-care imaging technology for diagnosing pneumonia. The objective was to explore LUS patterns associated with paediatric pneumonia. METHODS: We conducted a prospective, observational study among children aged 2 to 23â months with World Health Organization Integrated Management of Childhood Illness chest-indrawing pneumonia and among children without fast breathing, chest indrawing or fever (no pneumonia cohort) at two district hospitals in Mozambique and Pakistan. We assessed LUS and chest radiograph (CXR) examinations, and viral and bacterial nasopharyngeal carriage, and performed a secondary analysis of LUS patterns. RESULTS: LUS demonstrated a range of distinctive patterns that differed between children with and without pneumonia and between children in Mozambique versus Pakistan. The presence of LUS consolidation or interstitial patterns was more common in children with chest-indrawing pneumonia than in those without pneumonia. Consolidations were also more common among those with only bacterial but no viral carriage detected (50.0%) than among those with both (13.0%) and those with only virus detected (8.3%; p=0.03). LUS showed high interrater reliability among expert LUS interpreters for overall determination of pneumonia (κ=0.915), consolidation (κ=0.915) and interstitial patterns (κ=0.901), but interrater reliability between LUS and CXR for detecting consolidations was poor (κ=0.159, Pakistan) to fair (κ=0.453, Mozambique). DISCUSSION: Pattern recognition was discordant between LUS and CXR imaging modalities. Further research is needed to define and standardise LUS patterns associated with paediatric pneumonia and to evaluate the potential value of LUS as a reference standard.
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INTRODUCTION: Improved pneumonia diagnostics are needed in low-resource settings (LRS); lung ultrasound (LUS) is a promising diagnostic technology for pneumonia. The objective was to compare LUS versus chest radiograph (CXR), and among LUS interpreters, to compare expert versus limited training with respect to interrater reliability. METHODS: We conducted a prospective, observational study among children with World Health Organization (WHO) Integrated Management of Childhood Illness (IMCI) chest-indrawing pneumonia at two district hospitals in Mozambique and Pakistan, and assessed LUS and CXR examinations. The primary endpoint was interrater reliability between LUS and CXR interpreters for pneumonia diagnosis among children with WHO IMCI chest-indrawing pneumonia. RESULTS: Interrater reliability was excellent for expert LUS interpreters, but poor to moderate for expert CXR interpreters and onsite LUS interpreters with limited training. CONCLUSIONS: Among children with WHO IMCI chest-indrawing pneumonia, expert interpreters may achieve substantially higher interrater reliability for LUS compared to CXR, and LUS showed potential as a preferred reference standard. For point-of-care LUS to be successfully implemented for the diagnosis and management of pneumonia in LRS, the clinical environment and amount of appropriate user training will need to be understood and addressed.
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Pulmón/diagnóstico por imagen , Neumonía/diagnóstico por imagen , Femenino , Humanos , Lactante , Masculino , Mozambique , Pakistán , Radiografía Torácica , Reproducibilidad de los Resultados , UltrasonografíaRESUMEN
Monitoring the microbiological quality of water used for recreational activities is very important to human public health. Although the sanitary quality of recreational marine waters could be evaluated by standard methods, they are time-consuming and need confirmation. For these reasons, faster and more sensitive methods, such as the defined substrate-based technology, have been developed. In the present work, we have compared the standard method of membrane filtration using Tergitol-TTC agar for total coliforms and Escherichia coli, and Slanetz and Bartley agar for enterococci, and the IDEXX defined substrate technology for these faecal pollution indicators to determine the microbiological quality of natural recreational waters. ISO 17994:2004 standard was used to compare these methods. The IDEXX for total coliforms and E. coli, Colilert, showed higher values than those obtained by the standard method. Enterolert test, for the enumeration of enterococci, showed lower values when compared with the standard method. It may be concluded that more studies to evaluate the precision and accuracy of the rapid tests are required in order to apply them for routine monitoring of marine and freshwater recreational bathing areas. The main advantages of these methods are that they are more specific, feasible and simpler than the standard methodology.
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Técnicas Bacteriológicas/métodos , Monitoreo del Ambiente/métodos , Microbiología del Agua , Agua/normas , Humanos , Concentración de Iones de Hidrógeno , Recreación , Salinidad , Agua/química , Contaminación del AguaRESUMEN
BACKGROUND: Heterokont algae, together with cryptophytes, haptophytes and some alveolates, possess red-algal derived plastids. The chromalveolate hypothesis proposes that the red-algal derived plastids of all four groups have a monophyletic origin resulting from a single secondary endosymbiotic event. However, due to incongruence between nuclear and plastid phylogenies, this controversial hypothesis remains under debate. Large-scale genomic analyses have shown to be a powerful tool for phylogenetic reconstruction but insufficient sequence data have been available for red-algal derived plastid genomes. RESULTS: The chloroplast genomes of two brown algae, Ectocarpus siliculosus and Fucus vesiculosus, have been fully sequenced. These species represent two distinct orders of the Phaeophyceae, which is a major group within the heterokont lineage. The sizes of the circular plastid genomes are 139,954 and 124,986 base pairs, respectively, the size difference being due principally to the presence of longer inverted repeat and intergenic regions in E. siliculosus. Gene contents of the two plastids are similar with 139-148 protein-coding genes, 28-31 tRNA genes, and 3 ribosomal RNA genes. The two genomes also exhibit very similar rearrangements compared to other sequenced plastid genomes. The tRNA-Leu gene of E. siliculosus lacks an intron, in contrast to the F. vesiculosus and other heterokont plastid homologues, suggesting its recent loss in the Ectocarpales. Most of the brown algal plastid genes are shared with other red-algal derived plastid genomes, but a few are absent from raphidophyte or diatom plastid genomes. One of these regions is most similar to an apicomplexan nuclear sequence. The phylogenetic relationship between heterokonts, cryptophytes and haptophytes (collectively referred to as chromists) plastids was investigated using several datasets of concatenated proteins from two cyanobacterial genomes and 18 plastid genomes, including most of the available red algal and chromist plastid genomes. CONCLUSION: The phylogenetic studies using concatenated plastid proteins still do not resolve the question of the monophyly of all chromist plastids. However, these results support both the monophyly of heterokont plastids and that of cryptophyte and haptophyte plastids, in agreement with nuclear phylogenies.
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Evolución Molecular , Genoma del Cloroplasto/genética , Phaeophyceae/genética , Filogenia , Secuencia de Bases , Mapeo Cromosómico , ADN de Algas/genética , Fucus/genética , Datos de Secuencia Molecular , Plastidios/genética , Análisis de Secuencia de ADNRESUMEN
Fish has been recently recognized as a suitable vertebrate model and represents a promising alternative to mammals for studying mechanisms of tissue mineralization and unravelling specific questions related to vertebrate bone formation. The recently developed Sparus aurata (gilthead seabream) osteoblast-like cell line VSa16 was used to construct a cDNA subtractive library aimed at the identification of genes associated with fish tissue mineralization. Suppression subtractive hybridization, combined with mirror orientation selection, identified 194 cDNA clones representing 20 different genes up-regulated during the mineralization of the VSa16 extracellular matrix. One of these genes accounted for 69% of the total number of clones obtained and was later identified as theS. aurata osteopontin-like gene. The 2138-bp full-length S. aurata osteopontin-like cDNA was shown to encode a 374 amino-acid protein containing domains and motifs characteristic of osteopontins, such as an integrin receptor-binding RGD motif, a negatively charged domain and numerous post-translational modifications (e.g. phosphorylations and glycosylations). The common origin of mammalian osteopontin and fish osteopontin-like proteins was indicated through an in silico analysis of available sequences showing similar gene and protein structures and was further demonstrated by their specific expression in mineralized tissues and cell cultures. Accordingly, and given its proven association with mineral formation and its characteristic protein domains, we propose that the fish osteopontin-like protein may play a role in hard tissue mineralization, in a manner similar to osteopontin in higher vertebrates.