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OBJECTIVE: This study aimed to describe maternal characteristics and clinical outcomes of infants born to mothers with positive severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) tests during pregnancy at an urban, safety-net hospital in Boston. STUDY DESIGN: We abstracted electronic chart data from 75 pregnant women with positive SARS-CoV-2 tests at any stage of gestation until 72 hours after birth who delivered consecutively between March 31 and August 6, 2020 at our center. We collected clinical data on maternal and infant characteristics, including testing, signs, and symptoms of coronavirus disease 2019 (COVID-19), delivery outcomes, newborn care practices (skin-to-skin care, location of care, and breastfeeding) and 30-day postdischarge infant emergency room visits and readmissions. We described categorical characteristics as percentages for this case series. RESULTS: Among 75 pregnant women, 47 (63%) were Hispanic, 10 (13%) had hypertension, 23 (30%) had prepregnancy obesity, and 57 (76%) had symptomatic SARS-CoV-2 infection. Regarding birth outcomes, 32 (41%) had cesarean delivery and 14 (19%) had preterm birth. Among 75 infants, 5 (7%) had positive SARS-CoV-2 polymerase chain reaction tests in the first week of life, all of whom were born to Hispanic mothers with symptomatic SARS-CoV-2 infection and had clinical courses consistent with gestational age. Six (8%) infants visited the emergency department within 30 days of discharge; one was admitted with a non-COVID-19 diagnosis. CONCLUSION: At our urban, safety-net hospital among pregnant women with positive SARS-CoV-2 tests, 41% had a cesarean delivery and 19% had a preterm birth. Seven percent of infants had one or more positive SARS-CoV-2 tests and all infants had clinical courses expected for gestational age. KEY POINTS: · Among 75 pregnant women with SARS-CoV-2 positive testing at our center, five infants (7%) had one or more SARS-CoV-2 positive tests in the first week of life.. · Infants with positive SARS-CoV-2 tests had clinical courses expected for gestational age..
Assuntos
COVID-19 , Doenças do Recém-Nascido , Transmissão Vertical de Doenças Infecciosas , Complicações Infecciosas na Gravidez , SARS-CoV-2/isolamento & purificação , Adulto , Boston/epidemiologia , COVID-19/epidemiologia , COVID-19/terapia , COVID-19/transmissão , Cesárea/estatística & dados numéricos , Feminino , Idade Gestacional , Hospitalização/estatística & dados numéricos , Humanos , Cuidado do Lactente/métodos , Cuidado do Lactente/estatística & dados numéricos , Recém-Nascido , Doenças do Recém-Nascido/epidemiologia , Doenças do Recém-Nascido/virologia , Transmissão Vertical de Doenças Infecciosas/prevenção & controle , Transmissão Vertical de Doenças Infecciosas/estatística & dados numéricos , Gravidez , Complicações Infecciosas na Gravidez/epidemiologia , Complicações Infecciosas na Gravidez/terapia , Resultado da Gravidez , Nascimento Prematuro/epidemiologia , Provedores de Redes de Segurança/estatística & dados numéricosRESUMO
COVID-19 disease has been a pandemic caused by a ß-coronavirus severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). A life-threatening multisystem inflammatory syndrome (MIS), secondary to SARS-CoV-2 virus infection, sharing common features with Kawasaki disease shock syndrome, staphylococcal/streptococcal shock syndrome, and macrophage activation syndrome in pediatric patients has been described. A total of 27 cases in adults (MIS-A) with a similar presentation have been reported so far. Here we describe the case of a 21-year-old man admitted with abdominal pain, diarrhea, tachycardia, and low blood pressure. He had elevated troponin, ferritin, and interleukin-2 receptor levels and had evidence of myocarditis. He tested positive for SARS-CoV-2 IgG antibody, and a diagnosis of MIS-A was made. Our case adds to the scant literature on this topic, and to our knowledge, it is the first case where anakinra was administered. He recovered well. MIS-A should be considered when young adults present with multiorgan dysfunction.
RESUMO
BACKGROUND: Sialic acid has been shown to be a major virulence determinant in the pathogenesis of otitis media caused by the bacterium Haemophilus influenzae. This study aimed to characterise the expression of genes required for the metabolism of sialic acid and to investigate the role of these genes in virulence. RESULTS: Using qRT-PCR, we observed decreased transcriptional activity of genes within a cluster that are required for uptake and catabolism of 5-acetyl neuraminic acid (Neu5Ac), when bacteria were cultured in the presence of the sugar. We show that these uptake and catabolic genes, including a sialic acid regulatory gene (siaR), are highly conserved in the H. influenzae natural population. Mutant strains were constructed for seven of the nine genes and their influence upon LPS sialylation and resistance of the bacteria to the killing effect of normal human serum were assessed. Mutations in the Neu5Ac uptake (TRAP transporter) genes decreased virulence in the chinchilla model of otitis media, but the attenuation was strain dependent. In contrast, mutations in catabolism genes and genes regulating sialic acid metabolism (siaR and crp) did not attenuate virulence. CONCLUSION: The commensal and pathogenic behaviour of H. influenzae involves LPS sialylation that can be influenced by a complex regulatory interplay of sialometabolism genes.
Assuntos
Haemophilus influenzae/genética , Haemophilus influenzae/patogenicidade , Família Multigênica , Ácido N-Acetilneuramínico/metabolismo , Animais , Contagem de Células , Chinchila , Contagem de Colônia Microbiana , Sequência Conservada , Modelos Animais de Doenças , Humanos , Lipopolissacarídeos/química , Lipopolissacarídeos/metabolismo , Redes e Vias Metabólicas , Mutagênese , Ácido N-Acetilneuramínico/genética , Otite Média/microbiologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Soro , Virulência/genéticaRESUMO
Strategies to limit complement deposition on Streptococcus pneumoniae are established as virulence features for invasive disease, but their role in respiratory tract infection requires further analysis. We evaluated complement C3 protein deposition on discordant S. pneumoniae isolates of the same serotype (6A) and their capacity to cause nasopharyngeal (NP) colonization and experimental otitis media (EOM) in an animal model. We compared C3 binding to five 6A isolates from asymptomatic NP carriers with five 6A strains that caused invasive disease, and we observed less C3 ( approximately 10-fold less fluorescence) binding to invasive isolates. We selected two high-level C3-binding carriage and two low-level C3-binding invasive 6A isolates for further study. In the EOM model, 11/12 (92%) ears challenged with a low-level C3-binding 6A strain became infected. Only 2/8 (25%) ears challenged with the discordant high-level C3-binding 6A isolate developed disease (P = 0.005). Results with the second discordant 6A isolate pair were comparable. Cobra venom factor (CoVF) treatment, which depletes C3 and consumes complement, restored virulence of the high-level C3-binding strain; 8/8 (100%) ears in CoVF-treated animals developed EOM compared to only 25% of ears in naïve animals (P = 0.007). These studies demonstrate the critical role for complement evasion in pneumococcal EOM. Colonization with carriage isolates that bound high levels of C3 caused EOM in fewer animals compared to low-level C3-binding invasive strains. Thus, limiting C3 deposition on the surface of S. pneumoniae correlates with increased incidence of EOM following NP colonization and barotrauma in the animal model.
Assuntos
Complemento C3/imunologia , Otite Média/imunologia , Infecções Pneumocócicas/imunologia , Streptococcus pneumoniae/imunologia , Streptococcus pneumoniae/patogenicidade , Animais , Western Blotting , Chinchila , Ativação do Complemento/imunologia , Citometria de Fluxo , Humanos , Nasofaringe/imunologia , Nasofaringe/microbiologiaRESUMO
AIM: To characterize antibiotic (ab) prescriptions in children. METHODS: Evaluation of outpatient ab prescriptions in a 3-year cohort of children in primary care using a data warehouse (Massachusetts Health Disparities Repository) by comorbid conditions, demographics, and clinical indication. RESULTS: A total of 15 208 children with nearly 120 000 outpatient visits were included. About one third had a comorbid condition (most commonly asthma). Among the 30 000 ab prescriptions, first-line penicillins and macrolides represented the most frequent ab (70%), followed by cephalosporins (16%). Comorbid children had 54.3 ab prescriptions/100 child-years versus 38.8 in children without comorbidity; ab prescription was higher in urinary tract infections (>60% of episodes), otitis, lower respiratory tract infections (>50%), especially in comorbid children and children under 2 year old. Ab prescriptions were significantly associated with younger age, emergency room visit, comorbid children, and acute infections. DISCUSSION: A clinical data warehouse could help in designing appropriate antimicrobial stewardship programs and represent a potential assessment tool.
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Antibacterianos/uso terapêutico , Uso de Medicamentos , Prescrição Inadequada/estatística & dados numéricos , Infecções Respiratórias/tratamento farmacológico , Infecções Urinárias/tratamento farmacológico , Assistência Ambulatorial/métodos , Gestão de Antimicrobianos , Criança , Pré-Escolar , Estudos de Coortes , Data Warehousing , Prescrições de Medicamentos/estatística & dados numéricos , Feminino , Humanos , Lactente , Masculino , Massachusetts , Testes de Sensibilidade Microbiana , Pacientes Ambulatoriais/estatística & dados numéricos , Infecções Respiratórias/diagnóstico , Estudos Retrospectivos , Infecções Urinárias/diagnósticoRESUMO
Otitis media caused by nontypeable Haemophilus influenzae (NTHi) is a common and recurrent bacterial infection of childhood. The structural variability and diversity of H. influenzae lipopolysaccharide (LPS) glycoforms are known to play a significant role in the commensal and disease-causing behavior of this pathogen. In this study, we determined LPS glycoform populations from NTHi strain 1003 during the course of experimental otitis media in the chinchilla model of infection by mass spectrometric techniques. Building on an established structural model of the major LPS glycoforms expressed by this NTHi strain in vitro (M. Månsson, W. Hood, J. Li, J. C. Richards, E. R. Moxon, and E. K. Schweda, Eur. J. Biochem. 269:808-818, 2002), minor isomeric glycoform populations were determined by liquid chromatography multiple-step tandem electrospray mass spectrometry (LC-ESI-MS(n)). Using capillary electrophoresis ESI-MS (CE-ESI-MS), we determined glycoform profiles for bacteria from direct middle ear fluid (MEF) samples. The LPS glycan profiles were essentially the same when the MEF samples of 7 of 10 animals were passaged on solid medium (chocolate agar). LC-ESI-MS(n) provided a sensitive method for determining the isomeric distribution of LPS glycoforms in MEF and passaged specimens. To investigate changes in LPS glycoform distribution during the course of infection, MEF samples were analyzed at 2, 5, and 9 days postinfection by CE-ESI-MS following minimal passage on chocolate agar. As previously observed, sialic acid-containing glycoforms were detected during the early stages of infection, but a trend toward more-truncated and less-complex LPS glycoforms that lacked sialic acid was found as disease progressed.
Assuntos
Modelos Animais de Doenças , Infecções por Haemophilus/microbiologia , Haemophilus influenzae/patogenicidade , Lipopolissacarídeos/química , Lipopolissacarídeos/metabolismo , Otite Média/microbiologia , Animais , Chinchila , Cromatografia Líquida/métodos , Eletroforese Capilar/métodos , Infecções por Haemophilus/fisiopatologia , Haemophilus influenzae/metabolismo , Humanos , Isomerismo , Otite Média/fisiopatologia , Otite Média com Derrame/microbiologia , Espectrometria de Massas por Ionização por Electrospray/métodosRESUMO
Immigrant children who enter the United States without immunization records may be required to receive vaccines for diseases to which they are already immune or for which they have previously received immunization. We tested 669 newly arrived refugees (age range, 0-20 years) for antibody to measles, rubella, and varicella, to determine the seroprevalence of antibodies to these diseases in this group of immigrants. Five hundred forty-nine (82%) of 669 patients had antibody to measles, 545 (82%) of 668 had antibody to rubella, and 430 (64%) of 668 had antibody to varicella. Antibody to all 3 diseases increased with increasing age. No clinically significant differences in presence of antibody were noted by region of origin.
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Varicela/epidemiologia , Sarampo/epidemiologia , Rubéola (Sarampo Alemão)/epidemiologia , Adolescente , Adulto , África/epidemiologia , Distribuição por Idade , Anticorpos/imunologia , Varicela/imunologia , Criança , Pré-Escolar , Humanos , Lactente , Sarampo/imunologia , Prevalência , Refugiados , Rubéola (Sarampo Alemão)/imunologia , Estudos Soroepidemiológicos , Vietnã/epidemiologia , Iugoslávia/epidemiologiaRESUMO
BACKGROUND: It is unknown whether it is more cost-effective to test for varicella antibody or to immunize without testing in immigrant populations. The reliability of history of varicella disease is also unclear. METHODS: The prevalences of varicella antibody in immigrant children from six regions of the world were used in a cost-effectiveness model to calculate the antibody prevalence above which it is more cost-effective to test rather than to immunize. History of varicella disease was obtained from chart review. We calculated the positive and negative predictive values of varicella history by age group and region. RESULTS: The prevalence of varicella antibody above which it is more cost-effective to test than to immunize was 34% for children less than 13 years old and 17% for those aged 13 years and older. Overall, the positive predictive value of varicella history was 93-100% and the negative predictive value of varicella history was 28-66% among the six geographic regions. CONCLUSION: Immunization without serotesting was cost-effective in children <5 years of age. Testing prior to immunization was cost-effective in children 5 years of age and older. History of varicella was a good predictor of the presence of antibody to varicella, whereas a negative history was a poor predictor of the absence of antibody to varicella.
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Varicela/epidemiologia , Varicela/prevenção & controle , Herpesvirus Humano 3/imunologia , Vacinação em Massa/economia , Refugiados , Testes Sorológicos/economia , Adolescente , África Oriental/etnologia , Anticorpos Antivirais/análise , Boston/epidemiologia , Região do Caribe/etnologia , Varicela/sangue , Criança , Pré-Escolar , Análise Custo-Benefício , Ensaio de Imunoadsorção Enzimática/economia , Feminino , Herpesvirus Humano 3/isolamento & purificação , Humanos , Lactente , Iraque/etnologia , Masculino , Prevalência , Vietnã/etnologia , Iugoslávia/etnologiaRESUMO
We hypothesized that capsular switch event, in which pneumococcus acquires a new capsule operon by horizontal gene transfer, may result in emergence of strains with increased virulence in acute otitis media. Using serotype 6A strain from a patient with invasive pneumococcal disease and clonally distant serotype 6C strain isolated from asymptomatic carrier we created 6A:6C (6A background with 6C capsule) capsular transformants and applied whole genome macro-restriction analysis to assess conservation of the 6A chassis. Next, we assessed complement (C3) and antibodies deposition on surface of pneumococcal cells and tested capsule recipient, capsule donor and two 6A:6C transformants for virulence in chinchilla experimental otitis media model. Both 6A:6C(1 or 2) transformants bound less C3 compared to 6C capsule-donor strain but more compared to serotype 6A capsule-recipient strain. Pneumococci were present in significantly higher proportion of ears among animals challenged with either of two 6A:6C(1 or 2) transformants compared to chinchillas infected with 6C capsule-donor strain [p < 0.001] whereas a significantly decreased proportion of ears were infected with 6A:6C(1 or 2) transformants as compared to 6A capsule-recipient strain. Our observations though limited to two serotypes demonstrate that capsular switch events can result in Streptococcus pneumoniae strains of enhanced virulence for respiratory tract infection.
Assuntos
Cápsulas Bacterianas/química , Cápsulas Bacterianas/imunologia , Otite Média/imunologia , Otite Média/microbiologia , Streptococcus pneumoniae/química , Streptococcus pneumoniae/imunologia , Animais , Chinchila , Complemento C3/imunologia , Complemento C3/metabolismo , Modelos Animais de Doenças , Humanos , Otite Média/patologia , Infecções Pneumocócicas/imunologia , Infecções Pneumocócicas/microbiologia , Recombinação Genética , Streptococcus pneumoniae/isolamento & purificação , VirulênciaRESUMO
UNLABELLED: The pneumococcal Pilus-1 enhances attachment to epithelial cells in the respiratory tract and subsequent invasion. Pilus-1 expression is bi-stable and positively regulated by the RlrA transcriptional regulator. To delineate the role of pilus-1 in Experimental Otitis Media (EOM), we evaluated colonization and disease due to a Streptococcus pneumoniae (SP) wild type strain (Taiwan19F-14 wt) and its otherwise isogenic pilus-1 and pilus-2 deficient mutant (Taiwan19F-14 ΔPI-1/PI-2-) as well as potential for a chimeric protein (RrgB321) vaccine candidate for prevention of middle ear (ME) disease. METHODS: Chinchillas were challenged intranasally with either Taiwan19F-14 wt or Taiwan19F-14PI-1/PI-2 deficient mutant. ME status was assessed and direct cultures performed. New cohorts of animals were immunized with RrgB321 or alum. Intranasal challenge with Taiwan19F-14 wt [erythromycin susceptible E(S)] was performed. Subsequently, a second cohort of animals was immunized and challenged with either Taiwan19F-14 wt or a Pilus-1 over-expressing mutant [Taiwan19F-14+pMU1328_Pc-rlrA mutant; E resistant (R)] strain. Pilus-1 expression was analyzed in SP isolated from nasopharynx (NP) and ME fluids by flow cytometry. RESULTS: Culture positive EOM developed following challenge with either wild type SP (Taiwan19F-14) or its pilus-1 deficient mutant. Culture positive EOM developed following challenge with wild type in both RrgB321 immunized and control animals. Pilus-1 expression in ME fluids was significantly higher in controls compared to immunized chinchillas. In second cohort of immunized and control animals challenged with the over-expressing Pilus-1 mutant, delayed development of EOM in the immunized animals was observed. Pneumococci recovered from ME fluid of immunized animals were no longer E(R) signifying the loss of the pMU1328_Pc-rlrA plasmid. CONCLUSION: Pneumococcal pilus-1 was not essential for EOM. Regulation of Pilus-1 expression in ME fluids in the presence of anti RrgB321 antibody was essential for survival of S. pneumoniae. Pneumococci have evolved mechanisms of regulation of non-essential surface proteins to evade host defenses.
Assuntos
Proteínas de Bactérias/imunologia , Fímbrias Bacterianas/imunologia , Otite Média/imunologia , Otite Média/microbiologia , Vacinas Pneumocócicas/imunologia , Streptococcus pneumoniae/imunologia , Animais , Chinchila/imunologia , Chinchila/microbiologia , Contagem de Colônia Microbiana , Orelha Média/imunologia , Orelha Média/microbiologia , Imunização , Mutação/genética , Nasofaringe/imunologia , Nasofaringe/microbiologia , Otite Média/induzido quimicamente , Resultado do TratamentoRESUMO
Increases in colonization with serotypes of Streptococcus pneumoniae not contained within the 7-valent pneumococcal conjugate vaccine (PCV) have been reported among children following introduction. Serotype 6C has emerged as prevalent in nasopharyngeal colonization and acute otitis media (AOM), though it is uncommonly recovered from children with invasive pneumococcal disease. Vaccine serotypes within PCV7 have been replaced by nonvaccine serotypes without significant changes in the overall carriage rate. We hypothesize 1) that serotypes vary in their ability to evade host defenses and establish AOM following colonization and 2) the observed reduction in pneumococcal otitis results from a reduced disease potential by some 'replacement serotypes'. We compared the capacity of S. pneumoniae serotypes 6C and 19A to produce experimental otitis media (EOM) in a chinchilla model. The proportion of chinchillas that developed culture positive EOM and density of middle ear infection was evaluated. EOM was found in 28/82 (34%) ears challenged with 6C compared to 13/18(72.2%) with 19A [p = 0.0003]. When disease due to 6C did occur, it was characterized by low-density infection. Our findings demonstrate that challenge with serotype 6C results in EOM less frequently than 19A. These data support the need for greater knowledge regarding differences among serotypes to produce AOM.
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Otite Média/microbiologia , Otite Média/patologia , Infecções Pneumocócicas/microbiologia , Infecções Pneumocócicas/patologia , Streptococcus pneumoniae/classificação , Animais , Criança , Pré-Escolar , Chinchila , Modelos Animais de Doenças , Humanos , Nasofaringe/microbiologia , Otite Média/epidemiologia , Infecções Pneumocócicas/epidemiologia , Sorotipagem , Streptococcus pneumoniae/isolamento & purificação , Streptococcus pneumoniae/patogenicidade , VirulênciaRESUMO
Streptococcus pneumoniae is an important cause of otitis media and invasive disease. Since introduction of the heptavalent pneumococcal conjugate vaccine, there has been an increase in replacement disease due to serotype 19A clonal complex (CC)199 isolates. The goals of this study were to 1) describe genetic diversity among nineteen CC199 isolates from carriage, middle ear, blood, and cerebrospinal fluid, 2) compare CC199 19A (nâ=â3) and 15B/C (nâ=â2) isolates in the chinchilla model for pneumococcal disease, and 3) identify accessory genes associated with tissue-specific disease among a larger collection of S. pneumoniae isolates. CC199 isolates were analyzed by comparative genome hybridization. One hundred and twenty-seven genes were variably present. The CC199 phylogeny split into two main clades, one comprised predominantly of carriage isolates and another of disease isolates. Ability to colonize and cause disease did not differ by serotype in the chinchilla model. However, isolates from the disease clade were associated with faster time to bacteremia compared to carriage clade isolates. One 19A isolate exhibited hypervirulence. Twelve tissue-specific genes/regions were identified by correspondence analysis. After screening a diverse collection of 326 isolates, spr0282 was associated with carriage. Four genes/regions, SP0163, SP0463, SPN05002 and RD8a were associated with middle ear isolates. SPN05002 also associated with blood and CSF, while RD8a associated with blood isolates. The hypervirulent isolate's genome was sequenced using the Solexa paired-end sequencing platform and compared to that of a reference serotype 19A isolate, revealing the presence of a novel 20 kb region with sequence similarity to bacteriophage genes. Genetic factors other than serotype may modulate virulence potential in CC199. These studies have implications for the long-term effectiveness of conjugate vaccines. Ideally, future vaccines would target common proteins to effectively reduce carriage and disease in the vaccinated population.
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Variação Genética , Streptococcus pneumoniae/genética , Virulência , Animais , Chinchila , Modelos Animais de Doenças , Genes Bacterianos , Infecções Pneumocócicas/microbiologia , Streptococcus pneumoniae/patogenicidadeRESUMO
Non-vaccine Streptococcus pneumoniae serotypes are increasingly associated with disease. We evaluated isolates of the same sequence type (ST199) but different serotypes (15B/C, 19A) for growth in vitro, and pathogenic potential in a chinchilla otitis media model. We also developed a quantitative PCR (qPCR) assay to quantitatively assess each isolate, circumventing the need for selectable markers. In vitro studies showed faster growth of serotype 19A over 15B/C. Both were equally capable of colonization and middle ear infection in this model. Serotype 19A is included in new conjugate vaccine formulations while serotype 15B/C is not. Non-capsular vaccine targets will be important in disease prevention efforts.
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Otite Média/microbiologia , Vacinas Pneumocócicas/imunologia , Streptococcus pneumoniae/patogenicidade , Animais , Chinchila , Contagem de Colônia Microbiana/métodos , DNA Bacteriano/genética , Modelos Animais de Doenças , Reação em Cadeia da Polimerase/métodos , Sorotipagem , Streptococcus pneumoniae/classificação , VirulênciaRESUMO
Nontypeable (NT) Haemophilus influenzae is an important cause of otitis media in children. We have shown previously that NT H. influenzae mutants defective in their ability to sialylate lipopolysaccharide (LPS), called siaB mutants, show attenuated virulence in a chinchilla model of experimental otitis media (EOM). We show that complement is a key arm of host innate immunity against NT H. influenzae-induced EOM. Depleting complement in chinchillas by use of cobra venom factor (CoVF) rendered two otherwise avirulent siaB mutants fully virulent and able to cause EOM with severity similar to that of wild-type strains. Clearance of infection caused by siaB mutants in CoVF-treated animals coincided with reappearance of C3. Wild-type strains were more resistant to direct complement-mediated killing than their siaB mutants. The serum-resistant strain bound less C3 and C4 than the serum-sensitive strain. Neither NT H. influenzae strain tested bound factor H (alternative complement pathway regulator). Selective activation of the alternative pathway resulted in more C3 binding to siaB mutants. LPS sialylation had a more profound impact on the amount of alternative-pathway-mediated C3 binding ( approximately 5-fold decrease in fluorescence) when LPS was the main C3 target, as occurred on the more serum-resistant strain. In contrast, only an approximately 1.5-fold decrease in fluorescence intensity of C3 binding was seen with the serum-sensitive strain, where surface proteins predominantly bound C3. Differences in binding sites for C3 and C4 may account for variations in serum resistance between NT H. influenzae strains, which in turn may impact their virulence. These data demonstrate a central role for complement in innate immune defenses against NT H. influenzae infections and specifically EOM.
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Proteínas do Sistema Complemento/imunologia , Orelha Média/imunologia , Haemophilus influenzae tipo b/imunologia , Haemophilus influenzae tipo b/patogenicidade , Ácido N-Acetilneuramínico/metabolismo , Otite Média/imunologia , Animais , Western Blotting , Chinchila , Ativação do Complemento/imunologia , Proteínas do Sistema Complemento/metabolismo , Modelos Animais de Doenças , Citometria de Fluxo , Lipopolissacarídeos/imunologia , Lipopolissacarídeos/metabolismo , Otite Média/microbiologia , VirulênciaRESUMO
The typically recovered quantity of nontypeable Haemophilus influenzae (NTHi) bacteria in an ex vivo middle ear (ME) aspirate from the chinchilla model of experimental otitis media is insufficient for direct analysis of gene expression by microarray or of lipopolysaccharide glycoforms by mass spectrometry. This prompted us to investigate a strategy of multiple consecutive lavage samplings to increase ex vivo bacterial recovery. As multiple consecutive lavage samples significantly increased the total number of bacterial CFU collected during nasopharyngeal colonization or ME infection, this led us to evaluate whether bacteria sequentially acquired from consecutive lavages were similar. Comparative observation of complete ex vivo sample series by microscopy initially revealed ME inflammatory fluid consisting solely of planktonic-phase NTHi. In contrast, subsequent lavage samplings of the same infected ear revealed the existence of bacteria in two additional growth states, filamentous and biofilm encased. Gene expression analysis of such ex vivo samples was in accord with different bacterial growth phases in sequential lavage specimens. The existence of morphologically distinct NTHi subpopulations with varying levels of gene expression indicates that the pooling of specimens requires caution until methods for their separation are developed. This study based on multiple consecutive lavages is consistent with prior reports that NTHi forms a biofilm in vivo, describes the means to directly acquire ex vivo biofilm samples without sacrificing the animal, and has broad applicability for a study of mucosal infections. Moreover, this approach revealed that the actual burden of bacteria in experimental otitis media is significantly greater than was previously reported. Such findings may have direct implications for antibiotic treatment and vaccine development against NTHi.
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Biofilmes , Líquidos Corporais/microbiologia , Infecções por Haemophilus/microbiologia , Haemophilus influenzae/isolamento & purificação , Otite Média/microbiologia , Animais , Chinchila , Contagem de Colônia Microbiana , Modelos Animais de Doenças , Orelha Média/microbiologia , Perfilação da Expressão Gênica , Haemophilus influenzae/fisiologia , Microscopia de Fluorescência , Irrigação TerapêuticaRESUMO
Para evaluar si existen diferencias en el uso IV de Dexametasona o Hidrocortisona en la crisis de asma, 45 pacientes asmáticos no esteroideos dependientes fueron randomizados en 3 grupos. Se empleó técnica doble ciego. Dos grupos recibieron esteroides (Dexametasona o Hidrocortisona) en dosis única IV y un grupo placebo. Tratamiento adicional fue neubolizaciones con terbutalina. No se encontró diferencias en la evaluación inicial de los grupos en cuanto a severiadad del asma determinado por escala de fischi y PEFR inicial. Ocho pacientes presentaron recaídas (placebo: 6, esteroides: 2) Se encontró diferencias estadísticamente significativas entre los grupos hidrocortisona/Placebo (p:0.02) y Dexametasona/Placebo (p:0.03) no hubo diferencias entre los esteroides (p:1). La Hidrocortisona y dexametasona en la dosis y vía empleada no producen ningún efecto inmediato en la crisis aguda de asma, su uso precoz ayudará a prevenir las recaídas
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Humanos , Masculino , Feminino , Asma , Asma/complicações , Asma/diagnóstico , Dexametasona , HidrocortisonaRESUMO
Un estudio retrospectivo de 101 casos de pacientes que fueron intervenidos quirúrgicamente por presentar fractura de huesos largos, fue realizado en el Hospital Domingo Luciani de Caracas. Los casos fueron separados en 2 grupos: A (casos en los cuales se reportó infección postoperatoria), grupo B (casos en los que no se reportó infección postoperatoria). Fueron analizados 6 parámetros en ambos grupos: edad, atención primaria, estadía hospitalaria preoperatoria, tiempo de estadía hospitalaria postoperatoria, tipo de fractura (abierta o cerrada) y empleo de tracción esqelética previo al tratamiento quirúrgico definitivo. La incidencia de infección postoperatoria fue de 10,8%; la incidencia de infección en los casos de fractura abierta fue de 45,5%. Se encontró que 2 factores estaban relacionados con un alto riesgo para la aparición postoperatoria: estadía hospitalaria preoperatoria larga y la presencia de fractura abierta
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Humanos , Masculino , Fraturas Ósseas/cirurgia , Técnicas In Vitro , Infecção da Ferida CirúrgicaRESUMO
La Dermatomiositis Juvenil es una enfermedad inflamatoria y degenerativa del músculo estriado capaz de ocasionar errores diagnósticos y tratamientos inadecuados, debido a que su baja incidencia conduce a una falta de conocimiento entre los médicos. Presentamos un caso, ocurrido en el Hospital Privado Centro Médico de Caracas en Febrero de 1966, en un adolescente de 13 años con un cuadro clínico característico, pero con cifras alarmantes de creatininquinasa. La respuesta terapéutica fue excelente