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1.
J Pediatr Gastroenterol Nutr ; 79(3): 610-621, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39020449

RESUMO

OBJECTIVE: Genetic and environmental factors influence pathogenesis and rising incidence of paediatric inflammatory bowel disease (PIBD). The aim was to meta-analyse evidence of diet and environmental factors in PIBD. METHODS: A systematic search was conducted to identify diet and environmental factors with comparable risk outcome measures and had been reported in two or more PIBD studies for inclusion in meta-analyses. Those with ≥2 PIBD risk estimates were combined to provide pooled risk estimates. RESULTS: Of 4763 studies identified, 36 studies were included. PIBD was associated with higher risk with exposure to ≥/=4 antibiotic courses (includes prescriptions/purchases/courses), passive smoking, not being breastfed, sugary drink intake, being a non-Caucasian child living in a high-income country and infection history (odds ratio [OR] range: 2-3.8). Paediatric Crohn's disease (CD) was associated with higher risk with exposure to antibiotics during early childhood, ≥/=4 antibiotic courses, high socioeconomic status (SES), maternal smoking, history of atopic conditions and infection history (OR range: 1.6-4.4). A history of infection was also associated with higher risk of paediatric ulcerative colitis (UC) (OR: 3.73). Having a higher number of siblings (≥2) was associated with lower risk of paediatric CD (OR: 0.6) and paediatric UC (OR: 0.7). Pet exposure was associated with lower risk of paediatric UC (OR: 0.5). CONCLUSION: Several factors associated with PIBD risk were identified that could potentially be used to develop a disease screening tool. Future research is needed to address risk reduction in PIBD.


Assuntos
Antibacterianos , Doenças Inflamatórias Intestinais , Classe Social , Bebidas Adoçadas com Açúcar , Poluição por Fumaça de Tabaco , Criança , Humanos , Antibacterianos/efeitos adversos , Colite Ulcerativa/etiologia , Colite Ulcerativa/epidemiologia , Doença de Crohn/epidemiologia , Doença de Crohn/etiologia , Doenças Inflamatórias Intestinais/etiologia , Doenças Inflamatórias Intestinais/epidemiologia , Fatores de Risco , Bebidas Adoçadas com Açúcar/efeitos adversos , Poluição por Fumaça de Tabaco/efeitos adversos
2.
Environ Sci Technol ; 56(22): 16428-16440, 2022 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-36301735

RESUMO

Increasing CO2 emission has resulted in pressing climate and environmental issues. While abiotic and biotic processes mediating the fate of CO2 have been studied separately, their interactions and combined effects have been poorly understood. To explore this knowledge gap, an iron-reducing organism, Orenia metallireducens, was cultured under 18 conditions that systematically varied in headspace CO2 concentrations, ferric oxide loading, and dolomite (CaMg(CO3)2) availability. The results showed that abiotic and biotic processes interactively mediate CO2 acidification and sequestration through "chain reactions", with pH being the dominant variable. Specifically, dolomite alleviated CO2 stress on microbial activity, possibly via pH control that transforms the inhibitory CO2 to the more benign bicarbonate species. The microbial iron reduction further impacted pH via the competition between proton (H+) consumption during iron reduction and H+ generation from oxidization of the organic substrate. Under Fe(III)-rich conditions, microbial iron reduction increased pH, driving dissolved CO2 to form bicarbonate. Spectroscopic and microscopic analyses showed enhanced formation of siderite (FeCO3) under elevated CO2, supporting its incorporation into solids. The results of these CO2-microbe-mineral experiments provide insights into the synergistic abiotic and biotic processes that alleviate CO2 acidification and favor its sequestration, which can be instructive for practical applications (e.g., acidification remediation, CO2 sequestration, and modeling of carbon flux).


Assuntos
Compostos Férricos , Ferro , Compostos Férricos/química , Ferro/química , Dióxido de Carbono , Bicarbonatos , Carbonatos/química , Minerais , Oxirredução
3.
Environ Sci Technol ; 56(17): 12702-12712, 2022 09 06.
Artigo em Inglês | MEDLINE | ID: mdl-35980135

RESUMO

Uranium mining and nuclear fuel production have led to significant U contamination. Past studies have focused on the bioreduction of soluble U(VI) to insoluble U(IV) as a remediation method. However, U(IV) is susceptible to reoxidation and remobilization when conditions change. Here, we demonstrate that a combination of adsorption and bioreduction of U(VI) in the presence of an organic ligand (siderophore desferrioxamine B, DFOB) and the Fe-rich clay mineral nontronite partially alleviated this problem. DFOB greatly facilitated U(VI) adsorption into the interlayer of nontronite as a stable U(VI)-DFOB complex. This complex was likely reduced by bioreduction intermediates such as the Fe(II)-DFOB complex and/or through electron transfer within a ternary Fe(II)-DFOB-U(VI) complex. Bioreduction with DFOB alone resulted in a mobile aqueous U(IV)-DFOB complex, but in the presence of both DFOB and nontronite U(IV) was sequestered into a solid. These results provide novel insights into the mechanisms of U(VI) bioreduction and the stability of U and have important implications for understanding U biogeochemistry in the environment and for developing a sustainable U remediation approach.


Assuntos
Sideróforos , Urânio , Adsorção , Argila , Compostos Férricos , Compostos Ferrosos , Ferro , Minerais , Oxirredução
4.
Pediatr Transplant ; 25(8): e14092, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34313365

RESUMO

BACKGROUND: Pediatric retransplantation is an accepted practice for graft failure and complications in Australasia. As 15% of children require a third transplant, this is a growing cohort with limited data in the literature. METHODS: We review nine patients from the commencement of our transplantation program in 1986 up to 2020 assessing demographics, prognosis, and outcome measures. RESULTS: Third transplant patient survival was comparative to first and second transplant patient survival at 5 years. All deaths were within the post-operative period and secondary to sepsis. Operative times and transfusion volumes were increased at third transplant (1.8 and 4.5 times compared to first transplant, respectively). Learning difficulties and psychological disturbances were prevalent (83% and 66.6%, respectively). CONCLUSIONS: While recent mortality outcomes appear comparable to undergoing a second liver transplant, third transplant operations were more complex. Neurological impairment and psychological disturbance appear to be prevalent and need to be considered in pre-transplant counseling.


Assuntos
Transplante de Fígado/estatística & dados numéricos , Complicações Pós-Operatórias/cirurgia , Adolescente , Austrália , Criança , Pré-Escolar , Feminino , Rejeição de Enxerto , Sobrevivência de Enxerto , Humanos , Lactente , Masculino , Prognóstico , Reoperação/estatística & dados numéricos
5.
PLoS One ; 16(5): e0251883, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34014980

RESUMO

Iron reduction and sulfate reduction are two of the major biogeochemical processes that occur in anoxic sediments. Microbes that catalyze these reactions are therefore some of the most abundant organisms in the subsurface, and some of the most important. Due to the variety of mechanisms that microbes employ to derive energy from these reactions, including the use of soluble electron shuttles, the dynamics between iron- and sulfate-reducing populations under changing biogeochemical conditions still elude complete characterization. Here, we amended experimental bioreactors comprised of freshwater aquifer sediment with ferric iron, sulfate, acetate, and the model electron shuttle AQDS (9,10-anthraquinone-2,6-disulfonate) and monitored both the changing redox conditions as well as changes in the microbial community over time. The addition of the electron shuttle AQDS did increase the initial rate of FeIII reduction; however, it had little effect on the composition of the microbial community. Our results show that in both AQDS- and AQDS+ systems there was an initial dominance of organisms classified as Geobacter (a genus of dissimilatory FeIII-reducing bacteria), after which sequences classified as Desulfosporosinus (a genus of dissimilatory sulfate-reducing bacteria) came to dominate both experimental systems. Furthermore, most of the ferric iron reduction occurred under this later, ostensibly "sulfate-reducing" phase of the experiment. This calls into question the usefulness of classifying subsurface sediments by the dominant microbial process alone because of their interrelated biogeochemical consequences. To better inform models of microbially-catalyzed subsurface processes, such interactions must be more thoroughly understood under a broad range of conditions.


Assuntos
Bactérias/metabolismo , Ferro/metabolismo , Microbiota/genética , Sulfatos/metabolismo , Antraquinonas/química , Bactérias/química , Biodegradação Ambiental , Transporte de Elétrons/genética , Compostos Férricos/química , Água Subterrânea/química , Humanos , Oxirredução , RNA Ribossômico 16S/genética , Óxidos de Enxofre/química
6.
Med J Aust ; 213(10): 464-470, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-33015834

RESUMO

OBJECTIVE: To assess long term graft and patient survival after donor liver retransplantation in children in Australia and New Zealand during 1986-2017; to determine the factors that influence survival. DESIGN: Retrospective cohort analysis (registry data). SETTING, PARTICIPANTS: Australia and New Zealand Liver Transplant Registry data for all liver retransplantations in children (under 18 years of age), 1986-2017, in all four paediatric and six adult liver transplantation centres in the two countries. MAIN OUTCOME MEASURES: Graft and patient survival at one, 5, 10 and 15 years. RESULTS: 142 liver retransplantations were undertaken in children (59 during 1986-2000, 83 during 2001-2017). Kaplan-Meier survival analysis indicated that survival was significantly greater during 2001-2017 than 1986-2000 (P < 0.001). During 2001-2017, graft survival one year after retransplantation was 84%, at 5 years 75%, at 10 years 70%, and at 15 years 54%; patient survival was 89% at one year, 87% at 5 years, 87% at 10 years, and 71% at 15 years. Median time between transplantations was 0.2 years (IQR, 0.03-1.4 years) during 1986-2000, and 1.8 years (IQR, 0.1-6.8 years) during 2001-2017 (P = 0.002). The proportion of graft failures that involved split grafts was larger during 2001-2017 (35 of 83, 42%) than 1986-2000 (10 of 59, 17%). Graft type, cause of graft failure, and number of transplants did not influence survival following retransplantation. CONCLUSION: Survival for children following retransplantation is excellent. Graft survival is similar for split and whole grafts. Children on the liver waiting list requiring retransplantation should have the same access to donor grafts as children requiring a first transplant.


Assuntos
Transplante de Fígado/mortalidade , Reoperação , Adulto , Austrália/epidemiologia , Criança , Pré-Escolar , Feminino , Seguimentos , Sobrevivência de Enxerto , Humanos , Lactente , Estimativa de Kaplan-Meier , Transplante de Fígado/métodos , Masculino , Nova Zelândia/epidemiologia , Modelos de Riscos Proporcionais , Sistema de Registros , Estudos Retrospectivos , Doadores de Tecidos , Resultado do Tratamento , Listas de Espera
7.
Environ Sci Technol ; 54(16): 10128-10140, 2020 08 18.
Artigo em Inglês | MEDLINE | ID: mdl-32693580

RESUMO

Microbial iron reduction is a ubiquitous biogeochemical process driven by diverse microorganisms in a variety of environments. However, it is often difficult to separate the biological from the geochemical controls on bioreduction of Fe(III) oxides. Here, we investigated the primary driving factor(s) that mediate secondary iron mineral formation over a broad range of environmental conditions using a single dissimilatory iron reducer, Orenia metallireducens strain Z6. A total of 17 distinct geochemical conditions were tested with differing pH (6.5-8.5), temperature (22-50 °C), salinity (2-20% NaCl), anions (phosphate and sulfate), electron shuttle (anthraquinone-2,6-disulfonate), and Fe(III) oxide mineralogy (ferrihydrite, lepidocrocite, goethite, hematite, and magnetite). The observed rates and extent of iron reduction differed significantly with kint between 0.186 and 1.702 mmol L-1 day-1 and Fe(II) production ranging from 6.3% to 83.7% of the initial Fe(III). Using X-ray absorption and scattering techniques (EXAFS and XRD), we identified and assessed the relationship between secondary minerals and the specific environmental conditions. It was inferred that the observed bifurcation of the mineralization pathways may be mediated by differing extents of Fe(II) sorption on the remaining Fe(III) minerals. These results expand our understanding of the controls on biomineralization during microbial iron reduction and aid the development of practical applications.


Assuntos
Compostos Férricos , Firmicutes , Biomineralização , Ferro , Minerais , Oxirredução
8.
Vaccine ; 37(37): 5630-5636, 2019 09 03.
Artigo em Inglês | MEDLINE | ID: mdl-31402238

RESUMO

BACKGROUND: Human Papillomavirus (HPV) causes significant burden of HPV-related diseases, which are more prevalent in immunosuppressed compared to immunocompetent people. We conducted a multi-centre clinical trial to determine the immunogenicity and reactogenicity of HPV vaccine in immunocompromised children. Here we present the immunogenicity results 5 years post vaccination. METHODS: We followed up immunocompromised children (5-18 years) with a range of specified underlying conditions who were previously recruited from three Australian paediatric hospitals. Participants received three doses of quadrivalent HPV vaccine (Gardasil Quadrivalent HPV Types 6, 11, 16, 18) and were followed up between 2007 and 2016 (60 months post-vaccination). The immunogenicity primary outcome was seroconversion and geometric mean titres (GMT) of the quadrivalent HPV vaccine serotypes in the study. RESULTS: Of the 59 original participants, 37 were followed up at 60 months. The proportion of participants who seroconverted were: 86.5%, 89.2%, 89.2%, 91.9% by competitive Luminex immunoassay (cLIA) and 83.8%, 83.8%, 94.6%, 78.4% by total immunoglobulin G assays (IgG) for serotypes 6, 11, 16 and 18 respectively. GMT values ranged from 118 (95%CI: 79-177) for serotype 11, to 373 (95%CI: 215-649) for serotype 16 by cLIA. For IgG, serotype 16 had the highest GMT of 261 (95%CI: 143-477) and serotype 18 had the lowest value of 37 (95%CI: 21-68). All antibody titres were lower in females compared to males but the difference was not statistically significant except for serotype 16. No serious adverse event was reported during this follow-up period. CONCLUSION: Our evidence, although limited by small numbers, is reassuring that a three dose schedule of HPV vaccine remains immunogenic in immunocompromised children to five years post vaccination. Large scale studies are required to determine long term protection in immunocompromised children. CLINICAL TRIAL REGISTRATION: NCT02263703 (ClinicalTrials.gov).


Assuntos
Hospedeiro Imunocomprometido , Imunogenicidade da Vacina , Papillomaviridae/imunologia , Infecções por Papillomavirus/prevenção & controle , Vacinas contra Papillomavirus/imunologia , Adolescente , Adulto , Anticorpos Antivirais/imunologia , Criança , Pré-Escolar , Feminino , Seguimentos , Genótipo , Humanos , Imunoglobulina G/imunologia , Masculino , Papillomaviridae/classificação , Papillomaviridae/genética , Vacinas contra Papillomavirus/administração & dosagem , Soroconversão , Sorogrupo , Vacinação , Adulto Jovem
9.
Data Brief ; 25: 104375, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31467957

RESUMO

Datasets presented here were employed in the main work "Characterization of phthalate-degrading-bacteria from Asian carp microbiomes and riverine sediments" (Kolb et al., 2019a). The carcinogenic compounds dimethyl phthalate (DMP), diethyl phthalate (DEP), and dibutyl phthalate (DBP) are ubiquitous in the environment due to widespread production and distribution which can be taken up by aquatic organisms. Asian carp species silver (Hypophthalmichthys molitrix) and bighead (Hypophthalmichthys nobilis) are exposed to phthalates by ingestion and absorption. This article presents data on the characterization of phthalate-degrading bacteria isolated from Asian carp microbiomes and riverine sediments by means of sample collection, enrichment, and isolation. Graphical data presents substrate utilization profiles of consortium SK-1 and Rhodococcus ruber derived from the gut microbiome of H. molitrix. Additionally, phthalate-degrading microbes were isolated from the gut and scale microbiomes of Asian carp where scanning electron microscopy images show the morphology from samples of final enrichment cultures and isolates. Consortium SK-1 was subjected to amplicon sequencing where community data shows the distribution of taxa while enriched with 500 mg L-1 DMP, DEP, and DBP combined. The data presented can provide insights to future research since other phthalate-degrading isolates and consortia can potentially be isolated from the microbiomes of aquatic organisms.

11.
Pediatr Transplant ; 21(4)2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28332273

RESUMO

We aimed to assess the incidence of HAT over three eras following implementation of microvascular techniques and a customized anticoagulation protocol in a predominantly cadaveric split liver transplant program. We retrospectively reviewed pediatric liver transplants performed between April 1986 and 2016 and analyzed the incidence HAT over three eras. In E1, 1986-2008, each patient received a standard dose of 5 U/kg/h of heparin and coagulation profiles normalized passively. In E2, 2008-2012, microvascular techniques were introduced. In E3, 2012-2016, in addition, a customized anticoagulation protocol was introduced which included replacement of antithrombin 3, protein C and S, and early heparinization. A total of 317 liver transplants were completed during the study period, with a median age of 31.7 months. In E1, 22% of grafts were cadaveric in situ split grafts, while the second and third eras used split grafts in 59.0% and 64.9% of cases, respectively. HAT occurred in 9.5% in the first era, 11.5% (P=.661) in the second, and dropped to 1.8% in the third era (P=.043). A routine anticoagulation protocol has significantly reduced the incidence of HAT post-liver transplantation in children in a predominantly cadaveric in situ split liver transplant program.


Assuntos
Anticoagulantes/uso terapêutico , Artéria Hepática , Transplante de Fígado/métodos , Microcirurgia/métodos , Complicações Pós-Operatórias/prevenção & controle , Trombose/prevenção & controle , Procedimentos Cirúrgicos Vasculares/métodos , Criança , Pré-Escolar , Protocolos Clínicos , Terapia Combinada , Quimioterapia Combinada , Feminino , Artéria Hepática/cirurgia , Humanos , Incidência , Lactente , Masculino , Cuidados Pós-Operatórios/métodos , Complicações Pós-Operatórias/epidemiologia , Estudos Retrospectivos , Trombose/epidemiologia , Trombose/etiologia , Resultado do Tratamento
12.
J Pediatr Gastroenterol Nutr ; 64(2): 203-209, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-28107282

RESUMO

OBJECTIVES: Most infants with biliary atresia (BA) require liver transplantation (LT) after hepatoportoenterostomy (HPE), including those who initially clear jaundice. The aim of the present study was to identify clinical and routine laboratory factors in infants with BA post-HPE that predict native liver survival at 2 years. METHODS: A retrospective cohort study was conducted in 217 patients with BA undergoing HPE in Sydney, Australia and Toronto, Canada between January 1986 and July 2009. Univariate and multivariate logistic regression using backwards-stepwise elimination identified variables at 3 months after HPE most associated with 2-year native liver survival. RESULTS: Significant variables (P < 0.05) on univariate analysis included serum total bilirubin (TB) and albumin at 3 months post-HPE, bridging fibrosis or cirrhosis on initial liver biopsy, ascites of <3 months post-HPE, type 3 BA anatomy, age at HPE of >45 days, change in length z scores within 3 months of HPE, and center. On multivariate analysis, TB (P < 0.0001) and albumin (P = 0.02) at 3 months post-HPE, and center (P = 0.0003) were independently associated with native liver survival. Receiver operating characteristic analysis revealed an optimal cut-off value of TB <74 µmol/L (4.3 mg/dL; area under the receiver operating characteristic curve 0.8990) and serum albumin level >35 g/L (3.5 mg/dL; area under the receiver operating characteristic curve 0.7633) to predict 2-year native liver survival. TB and albumin levels 3 months post-HPE defined 3 groups (1: TB ≤74 µmol/L, albumin >35 g/L; 2: TB ≤74 µmol/L, albumin ≤35 g/L; 3: TB >74 µmol/L) with distinct short- and long-term native liver survival rates (log-rank P < 0.001). Length z scores 3 months post-HPE were poorer for group 2 than group 1 (-0.91 vs -0.30, P = 0.0217) with similar rates of coagulopathy. CONCLUSIONS: Serum TB and albumin levels 3 months post-HPE independently predicted native liver survival in BA when controlling for center. Serum albumin level <35 g/L in infants with BA who were no longer jaundiced at 3 months post-HPE was a poor prognostic indicator. Poorer linear growth and absence of significant coagulopathy suggest a role for early aggressive nutritional therapy in this group.


Assuntos
Atresia Biliar/cirurgia , Tomada de Decisão Clínica , Técnicas de Apoio para a Decisão , Doença Hepática Terminal/diagnóstico , Transplante de Fígado/estatística & dados numéricos , Portoenterostomia Hepática , Atresia Biliar/complicações , Pré-Escolar , Doença Hepática Terminal/etiologia , Doença Hepática Terminal/cirurgia , Feminino , Seguimentos , Indicadores Básicos de Saúde , Humanos , Lactente , Recém-Nascido , Modelos Logísticos , Masculino , Prognóstico , Curva ROC , Estudos Retrospectivos , Resultado do Tratamento
13.
J Pediatr Gastroenterol Nutr ; 64(6): 898-902, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-26960173

RESUMO

INTRODUCTION: Lower gastrointestinal endoscopy (LGIE)/colonoscopy is frequently performed for rectal bleeding, recurrent abdominal pain, and the diagnosis of inflammatory bowel disease (IBD). Although these are common indications, the causes of isolated rectal bleeding and recurrent abdominal pain in the otherwise well child have not been described. METHODS: A retrospective analysis of patients who had had an LGIE/colonoscopy from January 2001 to December 2010 was performed. The following data were collected: demographic data, indication, distance reached, macroscopic findings, microscopic findings, diagnosis, additional procedures, and complications. RESULTS: There were a total of 999 colonoscopies. The colonoscopy was normal in 390 of 999 (39%). The commonest indication for colonoscopy was a diagnosis of suspected IBD, 449 of 999 (45%). IBD was confirmed in 282 of 449 (63%), but colonoscopy was normal in 143 of 449 (32%) of suspected IBD. Colonoscopy was performed for rectal bleeding in 197 of 999 (20%) of whom 141 of 197 (72%) were normal. There were 46 (5%) colonoscopies performed for recurrent abdominal pain, which were all normal. Our completion rate to the cecum and beyond was 521 of 999 (52%). Our perforation rate during the 10 years was 0.2%. CONCLUSIONS: Colonoscopy is a safe procedure in pediatrics; however, 39% of colonoscopies in this series were normal. Many of these could have been avoided by eliminating colonoscopy in patients with recurrent abdominal pain in the absence of other clinical features, conservative management with laxatives for those with fresh blood per rectum typical of anal fissures, and fecal calprotectin screening before endoscopy in patients with suspected IBD.


Assuntos
Dor Abdominal/etiologia , Colonoscopia/estatística & dados numéricos , Hemorragia Gastrointestinal/etiologia , Doenças Inflamatórias Intestinais/diagnóstico por imagem , Padrões de Prática Médica/estatística & dados numéricos , Procedimentos Desnecessários/estatística & dados numéricos , Adolescente , Criança , Pré-Escolar , Colo/diagnóstico por imagem , Feminino , Humanos , Lactente , Recém-Nascido , Doenças Inflamatórias Intestinais/complicações , Masculino , Auditoria Médica , New South Wales , Pediatria , Reto/diagnóstico por imagem , Recidiva , Estudos Retrospectivos
14.
Int J Syst Evol Microbiol ; 66(10): 3964-3971, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27406851

RESUMO

A Gram-stain-negative, microaerophilic rod-shaped organism designated as strain Z9T was isolated from groundwater of 1.7 km depth from the Mt. Simon Sandstone of the Illinois Basin, Illinois, USA. Cells of strain Z9T were rod shaped with dimensions of 0.3×(1-10) µm and stained Gram-negative. Strain Z9T grew within the temperature range 20-60 °C (optimum at 30-40 °C), between pH 5 and 8 (optimum 5.2-5.8) and under salt concentrations of 1-5 % (w/v) NaCl (optimum 2.5 % NaCl). In addition to growth by fermentation and nitrate reduction, this strain was able to reduce Fe(III), Mn(IV), Co(III) and Cr(VI) when H2 or organic carbon was available as the electron donor, but did not actively reduce oxidized sulfur compounds (e.g. sulfate, thiosulfate or S0). The G+C content of the DNA from strain Z9T was 36.1 mol%. Phylogenetic analysis of the 16S rRNA gene from strain Z9T showed that it belongs to the class Bacilli and shares 97 % sequence similarity with the only currently characterized member of the genus Tepidibacillus, T.fermentans. Based on the physiological distinctness and phylogenetic information, strain Z9T represents a novel species within the genus Tepidibacillus, for which the name Tepidibacillus decaturensis sp. nov. is proposed. The type strain is Z9T (=ATCC BAA-2644T=DSM 103037T).


Assuntos
Bacillaceae/classificação , Água Subterrânea/microbiologia , Ferro/metabolismo , Filogenia , Bacillaceae/genética , Bacillaceae/isolamento & purificação , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Illinois , Oxirredução , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
15.
Vaccine ; 34(36): 4343-50, 2016 08 05.
Artigo em Inglês | MEDLINE | ID: mdl-27406936

RESUMO

AIM: The aim of this study was to determine the immunogenicity and reactogenicity of HPV vaccine in immunocompromised children. METHODS: A multi-centre clinical trial was conducted in three paediatric hospitals in Australia. Unvaccinated children 5-18years of age attending one of three paediatric hospitals with a range of specified conditions associated with immunosuppression were included. Quadrivalent HPV vaccine (Gardasil) was given to the participants and serum anti-HPV antibody levels were measured at baseline (before first dose), 7 and 24months after the first dose of vaccine. RESULTS: Fifty-nine participants were enrolled across the three paediatric hospitals and among those one was seropositive to types 6, 11 and 16 at baseline. Seven months after the first dose, seroconversion rates were 93.3%, 100%, 100% and 88.9% for type 6, 11, 16 and 18 respectively. The corresponding rates at 24month follow up were 82.2%, 91.1%, 91.1% and 68.9%. The greatest increase in geometric mean titre (GMT) was for type 16, followed by type 11. GMTs declined over the following months, but remained more than fourfold higher for all serotypes compared to baseline titres at 24months post vaccination. Injection site erythema, pain and swelling were commonly reported local adverse events and were less common after each dose. Few participants reported systemic adverse events, and minor disease flare occurred in two participants. One child developed a squamous cell oral carcinoma during follow up, but tissue was unable to be tested for HPV. CONCLUSION: Immunosuppressed children had an adequate immunogenic response to Quadrivalent HPV vaccine regardless of age and the cause of immunosuppression. HPV related cancers occur at higher frequency and earlier in immunosuppressed patients, so early vaccination and optimal scheduling should be further studied in such children. CLINICAL TRIAL REGISTRATION: NCT02263703 (ClinicalTrials.gov).


Assuntos
Vacina Quadrivalente Recombinante contra HPV tipos 6, 11, 16, 18/imunologia , Papillomavirus Humano 16/imunologia , Hospedeiro Imunocomprometido , Imunogenicidade da Vacina , Infecções por Papillomavirus/imunologia , Infecções por Papillomavirus/prevenção & controle , Adolescente , Anticorpos Antivirais/sangue , Austrália/epidemiologia , Criança , Pré-Escolar , Feminino , Vacina Quadrivalente Recombinante contra HPV tipos 6, 11, 16, 18/administração & dosagem , Vacina Quadrivalente Recombinante contra HPV tipos 6, 11, 16, 18/efeitos adversos , Humanos , Masculino , Infecções por Papillomavirus/epidemiologia , Infecções por Papillomavirus/virologia , Soroconversão , Fatores de Tempo , Vacinação
16.
PLoS One ; 11(1): e0146689, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26800443

RESUMO

Although iron- and sulfate-reducing bacteria in subsurface environments have crucial roles in biogeochemical cycling of C, Fe, and S, how specific electron donors impact the compositional structure and activity of native iron- and/or sulfate-reducing communities is largely unknown. To understand this better, we created bicarbonate-buffered batch systems in duplicate with three different electron donors (acetate, lactate, or glucose) paired with ferrihydrite and sulfate as the electron acceptors and inoculated them with subsurface sediment as the microbial inoculum. Sulfate and ferrihydrite reduction occurred simultaneously and were faster with lactate than with acetate. 16S rRNA-based sequence analysis of the communities over time revealed that Desulfotomaculum was the major driver for sulfate reduction coupled with propionate oxidation in lactate-amended incubations. The reduction of sulfate resulted in sulfide production and subsequent abiotic reduction of ferrihydrite. In contrast, glucose promoted faster reduction of ferrihydrite, but without reduction of sulfate. Interestingly, the glucose-amended incubations led to two different biogeochemical trajectories among replicate bottles that resulted in distinct coloration (white and brown). The two outcomes in geochemical evolution might be due to the stochastic evolution of the microbial communities or subtle differences in the initial composition of the fermenting microbial community and its development via the use of different glucose fermentation pathways available within the community. Synchrotron-based x-ray analysis indicated that siderite and amorphous Fe(II) were formed in the replicate bottles with glucose, while ferrous sulfide and vivianite were formed with lactate or acetate. These data sets reveal that use of different C utilization pathways projects significant changes in microbial community composition over time that uniquely impact both the geochemistry and mineralogy of subsurface environments.


Assuntos
Ácido Acético/metabolismo , Desulfotomaculum/metabolismo , Compostos Férricos/metabolismo , Glucose/metabolismo , Ácido Láctico/metabolismo , Consórcios Microbianos/fisiologia , Sulfatos/metabolismo , Sequência de Bases , Biodegradação Ambiental , Carbono/química , Carbonatos/metabolismo , DNA Bacteriano/genética , DNA Ribossômico/genética , Desulfotomaculum/genética , Elétrons , Metabolismo Energético/fisiologia , Compostos Ferrosos/metabolismo , Redes e Vias Metabólicas/fisiologia , Oxirredução , Fosfatos/metabolismo , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
17.
Science ; 344(6187): 1039-42, 2014 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-24789972

RESUMO

Microbial reduction of ferric iron [Fe(III)] is an important biogeochemical process in anoxic aquifers. Depending on groundwater pH, dissimilatory metal-reducing bacteria can also respire alternative electron acceptors to survive, including elemental sulfur (S(0)). To understand the interplay of Fe/S cycling under alkaline conditions, we combined thermodynamic geochemical modeling with bioreactor experiments using Shewanella oneidensis MR-1. Under these conditions, S. oneidensis can enzymatically reduce S(0) but not goethite (α-FeOOH). The HS(-) produced subsequently reduces goethite abiotically. Because of the prevalence of alkaline conditions in many aquifers, Fe(III) reduction may thus proceed via S(0)-mediated electron-shuttling pathways.


Assuntos
Compostos Férricos/metabolismo , Ferro/metabolismo , Shewanella/enzimologia , Enxofre/metabolismo , Álcalis/química , Reatores Biológicos , Transporte de Elétrons , Concentração de Íons de Hidrogênio , Compostos de Ferro/metabolismo , Redes e Vias Metabólicas , Minerais/metabolismo , Modelos Biológicos , Mutação , Oxirredução , Shewanella/genética , Termodinâmica
18.
Anesth Analg ; 118(5): 981-6, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24781568

RESUMO

BACKGROUND: Deep general anesthesia has been associated with increased mortality in 5 observational studies. The association may be causal or an epiphenomenon due to increased anesthetic sensitivity in high-risk patients. We conducted a pilot study to assess the feasibility of performing a definitive randomized controlled trial. The aims of the study were to determine whether anesthetic depth targeting in a high-risk group was feasible and to document anesthetic doses and arterial blood pressures associated with "deep" and "light" general anesthesia. METHODS: ASA physical status III and IV patients, aged ≥60 years, having surgery lasting ≥2 hours, with expected hospital stay ≥2 days, and receiving general anesthesia were randomly allocated to a Bispectral Index (BIS) or spectral entropy (SE) target of 35 ("low" group) or 50 ("high" group). The primary end point was mean BIS or SE. Secondary end points were postanesthesia care unit length of stay and pain scores, quality of recovery score, hospital length of stay, postoperative complications, and death. A composite end point of postoperative complications (pneumonia, myocardial infarction, stroke, pulmonary embolism, heart failure, and death) was determined at 1 year. RESULTS: One hundred twenty-five patients were recruited. The mean of the median BIS/SE values for each patient during the maintenance phase of anesthesia in the low and high groups was significantly different: 39 vs 48 (mean difference 8 [95% confidence interval {CI95}, 6 to 10], P < 0.001). There was also a significant difference in mean volatile anesthetic administration (minimum alveolar concentration): 0.98 vs 0.64 (mean difference -0.35 [CI95, -0.44 to -0.26], P < 0.001) and target propofol concentrations: 4.0 vs 3.1 µg/mL (mean difference -0.8 [CI95, -1.2 to -0.3], P = 0.004). Intraoperative mean arterial blood pressures were similar (85 vs 87 mm Hg; mean difference 2 [CI95, -2 to 6], P = 0.86), and there were no differences in short-term recovery characteristics or hospital length of stay. There was a significant difference in the incidence of wound infection at 30 days (13% vs 3%; risk difference -10% [CI95, -21 to -0.1], P = 0.04). At 1 year, the composite rates of complications in the low and high groups were 28% and 17% (risk difference -11 [CI95, -25 to 4], P = 0.15) and mortality rates were 12% and 9%, respectively (risk difference -2 [CI95, -14 to 9], P = 0.70). CONCLUSIONS: This pilot study demonstrated that depth of anesthesia targeting with BIS or SE was achievable in a high-risk population with adequate separation of processed electroencephalogram monitor targets. The expected incidence of postoperative complications and mortality occurred. We conclude that a large, multicenter, randomized controlled trial is feasible.


Assuntos
Anestesia/métodos , Resultado do Tratamento , Idoso , Período de Recuperação da Anestesia , Anestésicos/administração & dosagem , Comorbidade , Monitores de Consciência , Cuidados Críticos , Método Duplo-Cego , Eletroencefalografia , Determinação de Ponto Final , Entropia , Estudos de Viabilidade , Feminino , Humanos , Tempo de Internação , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Complicações Pós-Operatórias/epidemiologia , Estudos Prospectivos , Tamanho da Amostra
19.
Clin Nucl Med ; 38(6): 474-7, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23510885

RESUMO

An 8-year-old boy presented with first episode of rectal bleeding. Initial hemoglobin was 9 g/dL. A Meckel scan showed a hyperemic focus in the lower pelvis. Colonoscopy identified a juvenile polyp with dysplasia in the rectosigmoid region. It is important to carefully evaluate the dynamic flow images in the Meckel scan because pathology other than a Meckel diverticulum may be identified.


Assuntos
Pólipos/diagnóstico por imagem , Reto/diagnóstico por imagem , Reto/patologia , Pertecnetato Tc 99m de Sódio , Criança , Colonoscopia , Humanos , Masculino , Cintilografia
20.
J Pediatr Gastroenterol Nutr ; 56(1): 46-50, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22785414

RESUMO

OBJECTIVES: The aim of the present study was to report caregiver perceptions to antireflux surgery and gastrostomy in children with severe neurological impairment and to report the complications of the surgery. METHODS: Children were identified from a clinic database and clinical information and surgical complications were extracted from the database and hospital medical records. A cross-sectional questionnaire addressing severity of symptoms was administered to parents/caregivers and scored with a 5-point Likert scale (1 is much better to 5, much worse). RESULTS: A total of 122 children, median age 74 months (interquartile range 29-124), 63% spastic quadriplegic cerebral palsy, had antireflux surgery. Laparoscopic surgery was performed in 77 of 122 (63%) and 117 of 122 (96%) had gastrostomy insertion. Questionnaire was completed by 89 of 122 (73%) children; median duration of time from fundoplication to questionnaire was 77 months (43-89). The majority of caregivers indicated that surgery improved or greatly improved weight gain, chest infections, vomiting, and feeding tolerance. Only 2 caregivers reported that they regretted consenting to surgery. Serious surgical complications occurred in 10%. CONCLUSIONS: Serious complications were uncommon in this series of antireflux surgery in neurologically impaired children. Although gagging and retching were common following surgery, a high percentage of caregivers reported improved nutrition, reflux-related symptoms, and high levels of satisfaction.


Assuntos
Cuidadores , Refluxo Gastroesofágico/cirurgia , Doenças do Sistema Nervoso/complicações , Pais , Satisfação do Paciente , Percepção , Complicações Pós-Operatórias , Paralisia Cerebral/cirurgia , Criança , Estudos Transversais , Ingestão de Alimentos , Fundoplicatura , Refluxo Gastroesofágico/complicações , Gastrostomia , Humanos , Laparoscopia , Índice de Gravidade de Doença , Inquéritos e Questionários , Vômito
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