Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 118
Filtrar
1.
Appl Environ Microbiol ; 90(3): e0171323, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38319097

RESUMO

This study reports on the influence of a powder diet in a mouse model of oropharyngeal candidiasis (OPC), a significant health concern caused primarily by Candida albicans. Despite identical nutritional composition, we found that a powdered diet significantly increased Candida burdens and oral lesions, and aggravated weight loss compared to a standard pelleted diet. High fungal burdens and severe oral lesions were accomplished within 48 hours after infection with only one dose of cortisone. Moreover, mice on a powder diet recovered a week after infection. Using a powder diet, we thus modified the cortisone OPC murine model in a way that simplifies the infection process, enhances reproducibility, and facilitates studies investigating both pathogenesis and recovery processes. Our findings also underscore the pivotal role of the physical form of the diet in the progression and severity of oral Candida infection in this model. Future research should investigate this relationship further to broaden our understanding of the underlying mechanisms, potentially leading to novel prevention strategies and improved disease management.IMPORTANCEOropharyngeal candidiasis (OPC) is a multifactorial disease and a significant health concern. We found that the physical form of the diet plays a critical role in the severity and progression of OPC. We developed a modified cortisone OPC murine model that facilitates studies investigating pathogenesis and recovery processes.


Assuntos
Candidíase Bucal , Cortisona , Animais , Camundongos , Pós , Modelos Animais de Doenças , Cortisona/uso terapêutico , Reprodutibilidade dos Testes , Candidíase Bucal/tratamento farmacológico , Candidíase Bucal/microbiologia , Candidíase Bucal/patologia , Candida albicans , Dieta
2.
BJGP Open ; 7(4)2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37669805

RESUMO

BACKGROUND: Effective therapeutics given early to high-risk ambulatory patients with coronavirus disease 2019 (COVID-19) could improve outcomes and reduce overall healthcare burden. However, conducting site visits in non-hospitalised patients, who should remain isolated, is problematic. AIM: To evaluate the feasibility of a purely remote (virtual) study in non-hospitalised patients with COVID-19; and the efficacy and safety of nebulised recombinant interferon-ß1a (SNG001) in this setting. DESIGN & SETTING: Randomised, double-blind, parallel-group study, which was conducted remotely. METHOD: Eligible patients aged ≥65 years (or ≥50 years with risk factors) with COVID-19 and not requiring hospital admission were recruited remotely. They were randomised to SNG001 or placebo once-daily via nebuliser for 14 days. The main outcomes were assessments of feasibility and safety, which were all conducted remotely. RESULTS: Of 114 patients treated, 111 (97.4%) completed 28 days of follow-up. Overall compliance to study medication was high, with ≥13 doses taken by 89.7% and 92.9% of treated patients in the placebo and SNG001 groups, respectively. Over the course of the study, only two patients were hospitalised, both in the placebo group; otherwise there were no notable differences between treatments for the efficacy parameters. No patients withdrew owing to an adverse event, and a similar proportion of patients experienced on-treatment adverse events in the two treatment groups (64.3% and 67.2% with SNG001 and placebo, respectively); most were mild or moderate and not treatment-related. CONCLUSION: This study demonstrated that it is feasible to conduct a purely virtual study in community-based patients with COVID-19, when the study included detailed daily assessments and with medication administered via nebuliser.

3.
Microbiol Spectr ; : e0173423, 2023 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-37671879

RESUMO

Oral bacteria can influence the ability of Candida albicans to cause oropharyngeal candidiasis (OPC). We recently reported that a Lactobacillus johnsonii-enriched oral microbiota reduced C. albicans virulence in an immunosuppressed OPC mouse model. As a follow-up, in this work, we aimed to enrich the resident oral Lactobacillus communities with a prebiotic diet to further assess their effect on the severity of OPC. We tested the effect of a prebiotic xylo-oligosaccharides (XOS)-enriched diet in the oral global bacterial composition and severity of OPC. We assessed changes in the oral microbiome composition via 16S-rRNA gene high-throughput sequencing, validated by qPCR. The impact of the prebiotic diet on Candida infection was assessed by quantifying changes in oral fungal and bacterial biomass and scoring tongue lesions. Contrary to expectations, oral Lactobacillus communities were not enriched by the XOS-supplemented diet. Yet, XOS modulated the oral microbiome composition, increasing Bifidobacterium abundance and reducing enterococci and staphylococci. In the OPC model, the XOS diet attenuated Candida virulence and bacterial dysbiosis, increasing lactobacilli and reducing enterococci on the oral mucosa. We conclude that XOS attenuates Candida virulence by promoting a bacterial microbiome structure more resilient to Candida infection. IMPORTANCE This is the first study on the effects of a prebiotic diet on the oral mucosal bacterial microbiome and an oropharyngeal candidiasis (OPC) mouse model. We found that xylo-oligosaccharides change the oral bacterial community composition and attenuate OPC. Our results contribute to the understanding of the impact of the oral bacterial communities on Candida virulence.

4.
Urol Pract ; 10(6): 648-654, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37647173

RESUMO

INTRODUCTION: We evaluated germline and somatic testing practices and compared results from tissue and liquid biopsy specimens in a large community urology setting. METHODS: A retrospective analysis was performed on advanced prostate cancer patients from a single community practice between June 2016 and September 2021. Clinical data and sequencing results from tissue and liquid biopsy specimens were available for 389 patients. Genomic data were available for 81 tissues and 74 liquid biopsy specimens. Comparison of genomic findings included 81 tissues and 27 liquid biopsy specimens. The number of actionable biomarkers and patients screened and enrolled in clinical trials was assessed from germline and somatic testing. Frequency of pathogenically altered genes, alteration types, and biomarkers were assessed from tissue and liquid specimens. Alteration frequency was compared between specimen types for the top 25 altered genes. RESULTS: Clinically relevant alterations were found from germline and somatic testing in both tissue and liquid biopsy specimens. The frequency of microsatellite instability-high, tumor mutational burden-high, or alterations in homologous recombination repair genes was consistent with published findings. Concordance between tissue and liquid findings varied with low circulating tumor DNA. CONCLUSIONS: Germline and somatic testing is critical for treatment decisions and should be standard of care for community practices. Liquid biopsy is a viable alternative when circulating tumor DNA is high.

5.
Microbiol Resour Announc ; 12(5): e0008923, 2023 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-37042767

RESUMO

Lactobacillus johnsonii strain MT4, isolated from the oral cavity of C57BL/6 mice, elicits antimicrobial activity against disease-associated microorganisms. Short-read sequencing of the whole genome revealed a single genome of 1,883,026 bp, with a GC content of 34.4%, and no plasmids.

7.
mSphere ; 8(2): e0065622, 2023 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-36942961

RESUMO

As common commensals residing on mucosal tissues, Lactobacillus species are known to promote health, while some Streptococcus species act to enhance the pathogenicity of other organisms in those environments. In this study we used a combination of in vitro imaging of live biofilms and computational modeling to explore biofilm interactions between Streptococcus oralis, an accessory pathogen in oral candidiasis, and Lactobacillus paracasei, an organism with known probiotic properties. A computational agent-based model was created where the two species interact only by competing for space, oxygen, and glucose. Quantification of bacterial growth in live biofilms indicated that S. oralis biomass and cell numbers were much lower than predicted by the model. Two subsequent models were then created to examine more complex interactions between these species, one where L. paracasei secretes a surfactant and another where L. paracasei secretes an inhibitor of S. oralis growth. We observed that the growth of S. oralis could be affected by both mechanisms. Further biofilm experiments support the hypothesis that L. paracasei may secrete an inhibitor of S. oralis growth, although they do not exclude that a surfactant could also be involved. This contribution shows how agent-based modeling and experiments can be used in synergy to address multiple-species biofilm interactions, with important roles in mucosal health and disease. IMPORTANCE We previously discovered a role of the oral commensal Streptococcus oralis as an accessory pathogen. S. oralis increases the virulence of Candida albicans infections in murine oral candidiasis and epithelial cell models through mechanisms which promote the formation of tissue-damaging biofilms. Lactobacillus species have known inhibitory effects on biofilm formation of many microbes, including Streptococcus species. Agent-based modeling has great advantages as a means of exploring multifaceted relationships between organisms in complex environments such as biofilms. Here, we used an iterative collaborative process between experimentation and modeling to reveal aspects of the mostly unexplored relationship between S. oralis and L. paracasei in biofilm growth. The inhibitory nature of L. paracasei on S. oralis in biofilms may be exploited as a means of preventing or alleviating mucosal fungal infections.

8.
Clin Infect Dis ; 75(Suppl 2): S308-S316, 2022 10 03.
Artigo em Inglês | MEDLINE | ID: mdl-35675310

RESUMO

BACKGROUND: The objective was to estimate risk of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection in pregnancy and assess adverse maternal and perinatal outcomes. METHODS: We used a population-based, retrospective cohort of all pregnancies with a live birth or fetal death in Florida from 1 March 2020 to 30 April 2021. Coronavirus disease 2019 (COVID-19) case reports were matched to vital registries. Outcomes assessed were risk of infection in pregnancy, preterm birth, maternal or neonatal admission to an intensive care unit (ICU), perinatal or fetal death, and maternal death. Modified Poisson and multinomial logistic regression models were used to derive relative risk estimates. RESULTS: Of 234 492 women with a live birth or fetal death during the study period, 12 976 (5.5%) were identified with COVID-19 during pregnancy. Risk factors for COVID-19 in pregnancy included Hispanic ethnicity (relative risk [RR] = 1.89), Black race (RR = 1.34), being unmarried (RR = 1.04), and being overweight or obese pre-pregnancy (RR = 1.08-1.32). COVID-19 during pregnancy was associated with preterm birth (RR = 1.31), Cesarean delivery (RR = 1.04), and neonatal (RR = 1.17) and maternal (RR = 3.10) ICU admission; no association was found with increased risk of perinatal (RR = 0.72) or fetal death (RR = 0.86). Women infected during any trimester showed increased risk of preterm birth. Fourteen maternal deaths were identified among COVID-19 cases; of those who died, 12 were obese. The death rate per 10 000 was 22.09 among obese and 1.22 among non-obese gravida with COVID-19 during pregnancy (RR = 18.99, P = .001). CONCLUSIONS: Obesity is a risk factor for SARS-CoV-2 infection in pregnancy and for more severe COVID-19 illness among pregnant women. SARS-CoV-2 infection is associated with preterm birth.


Assuntos
COVID-19 , Complicações Infecciosas na Gravidez , Nascimento Prematuro , COVID-19/epidemiologia , Feminino , Morte Fetal , Florida/epidemiologia , Humanos , Recém-Nascido , Transmissão Vertical de Doenças Infecciosas , Gravidez , Complicações Infecciosas na Gravidez/epidemiologia , Resultado da Gravidez/epidemiologia , Nascimento Prematuro/epidemiologia , Estudos Retrospectivos , SARS-CoV-2
9.
Sci Rep ; 12(1): 8617, 2022 05 21.
Artigo em Inglês | MEDLINE | ID: mdl-35597795

RESUMO

The objective of this study was to characterize head biomechanics of video-recorded falls involving young children in a licensed childcare setting. Children 12 to < 36 months of age were observed using video monitoring during daily activities in a childcare setting (in classrooms and outdoor playground) to capture fall events. Sensors (SIM G) incorporated into headbands worn by the children were used to obtain head accelerations and velocities during falls. The SIM G device was activated when linear acceleration was ≥ 12 g. 174 video-recorded falls activated the SIM G device; these falls involved 31 children (mean age = 21.6 months ± 5.6 SD). Fall heights ranged from 0.1 to 1.2 m. Across falls, max linear head acceleration was 50.2 g, max rotational head acceleration was 5388 rad/s2, max linear head velocity was 3.8 m/s and max rotational head velocity was 21.6 rad/s. Falls with head impact had significantly higher biomechanical measures. There was no correlation between head acceleration and fall height. No serious injuries resulted from falls-only 1 child had a minor injury. In conclusion, wearable sensors enabled characterization of head biomechanics during video-recorded falls involving young children in a childcare setting. Falls in this setting did not result in serious injury.


Assuntos
Aceleração , Cuidado da Criança , Fenômenos Biomecânicos , Estatura , Criança , Pré-Escolar , Cabeça , Humanos , Lactente
10.
Front Microbiol ; 13: 853762, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35330775

RESUMO

Lactobacillus johnsonii is a probiotic bacterial species with broad antimicrobial properties; however, its antimicrobial activities against the pathobiont Candida albicans are underexplored. The aim of this study was to study the interactions of L. johnsonii with C. albicans and explore mechanisms of bacterial anti-fungal activities based on bacterial genomic characterization coupled with experimental data. We isolated an L. johnsonii strain (MT4) from the oral cavity of mice and characterized its effect on C. albicans growth in the planktonic and biofilm states. We also identified key genetic and phenotypic traits that may be associated with a growth inhibitory activity exhibited against C. albicans. We found that L. johnsonii MT4 displays pH-dependent and pH-independent antagonistic interactions against C. albicans, resulting in inhibition of C. albicans planktonic growth and biofilm formation. This antagonism is influenced by nutrient availability and the production of soluble metabolites with anticandidal activity.

11.
Clin Anat ; 35(3): 305-315, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34881441

RESUMO

The objective of this study was to characterize femur morphology in healthy infants and young children. Anterior-posterior (AP) radiographs of the femur from children age 0-3 years with no history of bone disease were obtained from two children's hospitals and one medical examiner's office. Femur morphological measures (bone length, minimum diaphysis diameter, growth plate width, and femur radius of curvature) and sectional structural measures were determined. Measures were described and compared based on subject age and mass. Relationships between measures and age and mass were evaluated. The 169 AP femur radiographs were obtained from 99 children (59.6% males, median age = 12.0 months, IQR = 0-27.5 months, median body weight = 10.0 kg, IQR = 4.4-15.6 kg). Femur length (rs  = 0.97, p < 0.001; rs  = 0.89, p < 0.001), trochanter width (rs  = 0.86, p < 0.001; rs  = 0.85, p < 0.001), minimum diaphysis diameter (rs  = 0.91, p < 0.001; rs  = 0.87, p < 0.001), and growth plate width (rs  = 0.91, p < 0.001; rs  = 0.84, p < 0.001) increased with age and weight, respectively. Cross-sectional area (rs  = 0.87; rs  = 0.86; p < 0.01), polar moment of inertia (rs  = 0.91; rs  = 0.87; p < 0.001), moment of inertia (rs  = 0.91; rs  = 0.87; p < 0.001), polar modulus (rs  = 0.91; rs  = 0.87; p < 0.001) and medullary canal diameter (rs  = 0.83, p < 0.001; rs  = 0.73, p < 0.001) at the minimum diaphysis also increased with age and weight, respectively. Changes during rapid bone growth are important to understanding fracture risk in infants and young children as they transition to independent walking. Femur length, trochanter width, minimum diaphysis diameter and growth plate width increased with age and weight. Structural properties associated with fracture resistance also increased with age and weight.


Assuntos
Fêmur , Fraturas Ósseas , Densidade Óssea , Desenvolvimento Ósseo , Criança , Pré-Escolar , Diáfises/diagnóstico por imagem , Feminino , Fêmur/anatomia & histologia , Fêmur/diagnóstico por imagem , Humanos , Lactente , Recém-Nascido , Masculino , Rádio (Anatomia)
12.
Am J Perinatol ; 39(4): 337-341, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34839479

RESUMO

OBJECTIVE: Optimal prescriptions practices of opioids in the post-cesarean period remain controversial. The primary aim of this initiative was to minimize unused prescription narcotic medication, with a goal of ≤4 leftover pills of 5-mg oxycodone at postoperative day (POD) 14 without affecting pain or satisfaction measures. STUDY DESIGN: This was a prospective longitudinal quality improvement (QI) initiative starting in 2017 utilizing the DMAIC methodology. The measurement phase consisted of validated surveys over 3 months, along with chart review to determine current institutional prescription practices and predictors of outpatient opioid use. Resulting recommendations were adopted, and 1 year later, all patients undergoing cesarean were surveyed for 3 months to determine the effectiveness of the intervention. The study was approved by the Department's QI Committee. RESULTS: The response rate was 48%, with 50 of 101 patients completing surveys pre-intervention and 52 of 111 post-intervention. Pre-intervention, surplus medication was predicted (p <0.05) only by the quantity of the opioid prescription. In addition, patients who required ≤37.5 morphine milligram equivalents (MMEs) during the inpatient postoperative stay did not require outpatient narcotic prescriptions. Thereafter, a strategy of matching inpatient use to outpatient prescription 1:1 in a linear regression model (p <0.001, R 2 0.55) optimally matched patient needs up to 200 MME. In the post-intervention survey, mean (SD) prescription decreased from 17.6 (13.7) MME to 8.4 (8.3) MME (p <0.01); 39% compared with 16% of women were discharged without a prescription (p <0.01); and amongst all patients 82.7% compared with 59.6% (p <0.01) had ≤4 pills remaining without differences in patient satisfaction or pain perception. CONCLUSION: This initiative highlights a practical approach to QI utilizing industry techniques in health care. This approach resulted in significant reductions in over-prescription and unused medication, without impacting pain or satisfaction scores. KEY POINTS: · 20% of patients may manage pain at home without opioids.. · In-hospital opioid use is reflective of outpatient need.. · Customize prescriptions to reduce leftover narcotics..


Assuntos
Analgésicos Opioides , Dor Pós-Operatória , Analgésicos Opioides/uso terapêutico , Feminino , Humanos , Entorpecentes/uso terapêutico , Dor Pós-Operatória/tratamento farmacológico , Padrões de Prática Médica , Gravidez , Prescrições , Estudos Prospectivos , Melhoria de Qualidade
13.
mSphere ; 6(6): e0087521, 2021 12 22.
Artigo em Inglês | MEDLINE | ID: mdl-34908459

RESUMO

As common commensals residing on mucosal tissues, Lactobacillus species are known to promote health, while some Streptococcus species act to enhance the pathogenicity of other organisms in those environments. In this study, we used a combination of in vitro imaging of live biofilms and computational modeling to explore biofilm interactions between Streptococcus oralis, an accessory pathogen in oral candidiasis, and Lactobacillus paracasei, an organism with known probiotic properties. A computational agent-based model was created where the two species interact only by competing for space, oxygen and glucose. Quantification of bacterial growth in live biofilms indicated that S. oralis biomass and cell numbers were much lower than predicted by the model. Two subsequent models were then created to examine more complex interactions between these species, one where L. paracasei secretes a surfactant, and another where L. paracasei secretes an inhibitor of S. oralis growth. We observed that the growth of S. oralis could be affected by both mechanisms. Further biofilm experiments support the hypothesis that L. paracasei may secrete an inhibitor of S. oralis growth, although they do not exclude that a surfactant could also be involved. This contribution shows how agent-based modeling and experiments can be used in synergy to address multiple species biofilm interactions, with important roles in mucosal health and disease. IMPORTANCE We previously discovered a role of the oral commensal Streptococcus oralis as an accessory pathogen. S. oralis increases the virulence of Candida albicans infections in murine oral candidiasis and epithelial cell models through mechanisms which promote the formation of tissue-damaging biofilms. Lactobacillus species have known inhibitory effects on biofilm formation of many microbes, including Streptococcus species. Agent-based modeling has great advantages as a means of exploring multifaceted relationships between organisms in complex environments such as biofilms. Here, we used an iterative collaborative process between experimentation and modeling to reveal aspects of the mostly unexplored relationship between S. oralis and L. paracasei in biofilm growth. The inhibitory nature of L. paracasei on S. oralis in biofilms may be exploited as a means of preventing or alleviating mucosal fungal infections.


Assuntos
Biofilmes/crescimento & desenvolvimento , Lacticaseibacillus paracasei/crescimento & desenvolvimento , Streptococcus oralis/crescimento & desenvolvimento , Análise de Sistemas , Virulência
15.
J Pharm Pract ; 34(1): 58-63, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31238771

RESUMO

BACKGROUND: Pharmacists in ambulatory care can utilize population health approaches to identify patients needing disease management and improve outcomes. However, population health is only effective when identified patients are successfully outreached and show to appointments. OBJECTIVE: Describe a population health approach utilized by pharmacists in primary care, report outcomes of outreach attempts and scheduled appointments, and determine whether patient and referral characteristics predict no-show appointments. METHODS: Retrospective cohort study of patients referred for pharmacist management of hypertension or chronic pain through population health between 2013-2016. Outreach attempt and appointments outcomes were collected. Patient and referral characteristics were analyzed to determine whether predictive of no-show appointments using logistic regression. RESULTS: Of 450 outreach attempts, 250 (56%) patients were not reached, 164 (36%) scheduled appointments, and 36 (8%) were reached but declined an appointment. Of 164 patients with appointments, 71 (43%) no-showed. Patients with higher systolic blood pressure were more likely to no-show (OR: 1.02, 95% CI: 1.00-1.04). Other characteristics were not predictive of no-show appointments. CONCLUSION: Successful outreach and showed appointments are essential components of successful population health programs. Using multiple outreach modalities and further identifying factors predictive of no-show appointments to refine the current approach may lead to increased efficiency.


Assuntos
Serviço de Farmácia Hospitalar , Gestão da Saúde da População , Humanos , Farmacêuticos , Avaliação de Programas e Projetos de Saúde , Estudos Retrospectivos
16.
Comput Methods Biomech Biomed Engin ; 24(5): 517-526, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33115286

RESUMO

A finite element (FE) model of an 11-month-old child's femur was developed to evaluate fracture risk in short-distance feet-first falls and bed falls. Pediatric material properties were applied to the FE model. Femur loading was derived from previously conducted fall experiments using a child surrogate where fall conditions (e.g., fall height, impact surface) were varied. Fracture thresholds based on principal stress and strain were used to examine potential for fracture. Peak stress/strain were significantly greater for feet-first falls from greater heights and onto harder impact surfaces. Feet-first falls exceeded some, but not all fracture thresholds. Bed falls did not exceed any fracture thresholds.


Assuntos
Acidentes por Quedas , Fraturas do Fêmur/diagnóstico , Análise de Elementos Finitos , Fenômenos Biomecânicos , Criança , Fraturas do Fêmur/fisiopatologia , Fêmur , Humanos , Lactente , Manequins , Reprodutibilidade dos Testes , Estresse Mecânico
18.
Appl Environ Microbiol ; 86(9)2020 04 17.
Artigo em Inglês | MEDLINE | ID: mdl-32111586

RESUMO

Streptococci from the mitis group (represented mainly by Streptococcus mitis, Streptococcus oralis, Streptococcus sanguinis, and Streptococcus gordonii) form robust biofilms with Candida albicans in different experimental models. These microorganisms have been found in polymicrobial biofilms forming on titanium biomaterial surfaces in humans with peri-implant disease. The purpose of this work was to study mutualistic interactions in biofilms forming on titanium and their effect on the adjacent mucosa, using a relevant infection model. Single and mixed biofilms of C. albicans and each Streptococcus species were grown on titanium disks. Bacterial and fungal biovolume and biomass were quantified in these biofilms. Organotypic mucosal constructs were exposed to preformed titanium surface biofilms to test their effect on secretion of proinflammatory cytokines and cell damage. C. albicans promoted bacterial biofilms of all mitis Streptococcus species on titanium surfaces. This relationship was mutualistic since all bacterial species upregulated the efg1 hypha-associated gene in C. albicans Mixed biofilms caused increased tissue damage but did not increase proinflammatory cytokine responses compared to biofilms comprising Candida alone. Interestingly, spent culture medium from tissues exposed to titanium biofilms suppressed Candida growth on titanium surfaces.IMPORTANCE Our findings provide new insights into the cross-kingdom interaction between C. albicans and Streptococcus species representative of the mitis group. These microorganisms colonize titanium-based dental implant materials, but little is known about their ability to cause inflammation and damage of the adjacent mucosal tissues. Using an in vitro biomaterial-mucosal interface infection model, we showed that mixed biofilms of each species with C. albicans enhance tissue damage. One possible mechanism for this effect is the increased fungal hypha-associated virulence gene expression we observed in mixed biofilms with these species. Interestingly, we also found that the interaction of multispecies biofilms with organotypic mucosal surfaces led to the release of growth-suppressing mediators of Candida, which may represent a homeostatic defense mechanism of the oral mucosa against fungal overgrowth. Thus, our findings provide novel insights into biofilms on biomaterials that may play an important role in the pathogenesis of mucosal infections around titanium implants.


Assuntos
Biofilmes , Candida albicans/fisiologia , Mucosa Bucal/microbiologia , Streptococcus gordonii/fisiologia , Titânio/fisiologia , Estreptococos Viridans/fisiologia , Humanos
19.
ISME J ; 14(5): 1207-1222, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32042100

RESUMO

Streptococcal glucosyltransferases (Gtf) synthesize α-glucan exopolymers which contribute to biofilm matrix. Streptococcus oralis interacts with the opportunistic pathogen Candida albicans to form hypervirulent biofilms. S. oralis 34 has a single gtf gene (gtfR). However, the role of gtfR in single and mixed species biofilms with C. albicans has never been examined. A gtfR deletion mutant, purified GtfR, and recombinant GtfR glucan-binding domain were tested in single and mixed biofilms on different substrata in vitro. A mouse oral infection model was also used. We found that in single species biofilms growing with sucrose on abiotic surfaces S. oralis gtfR increased biofilm matrix, but not bacterial biomass. In biofilms with C. albicans, S. oralis encoding gtfR showed increased bacterial biomass on all surfaces. C. albicans had a positive effect on α-glucan synthesis, and α-glucans increased C. albicans accretion on abiotic surfaces. In single and mixed infection of mice receiving sucrose S. oralis gtfR enhanced mucosal burdens. However, sucrose had a negative impact on C. albicans burdens and reduced S. oralis burdens in co-infected mice. Our data provide new insights on the GtfR-mediated interactions between the two organisms and the influence of biofilm substratum and the mucosal environment on these interactions.


Assuntos
Biofilmes , Candida albicans/fisiologia , Glucosiltransferases/metabolismo , Streptococcus oralis/fisiologia , Animais , Candida albicans/genética , Glucanos , Sistema da Enzima Desramificadora do Glicogênio , Camundongos , Streptococcus , Streptococcus mutans/genética , Streptococcus oralis/genética
20.
Pediatr Radiol ; 50(5): 726-733, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-31925459

RESUMO

BACKGROUND: The presumed mechanism of rib fractures in abuse is violent grasping of the torso causing anterior-posterior chest compression. We hypothesized an asymmetrical distribution of rib fractures in abused infants given the greater incidence of right-hand dominance within the general population. OBJECTIVE: The objective of this study was to characterize rib fractures in abused children, particularly sidedness; additionally, we evaluated the sidedness of other abusive skeletal fractures. MATERIALS AND METHODS: We reviewed medical records from abused children (0-18 months old) with rib fractures. We also retrospectively reviewed their radiographs to determine characteristics of rib fractures (number, side, rib region, level, acuity) and other skeletal fractures (number, side, location), as well as differences in the distribution of rib and other skeletal fractures. RESULTS: A total of 360 rib fractures were identified on 273 individual ribs involving 78 abused children. Sixty-three children (81%) had multiple rib fractures. There was a significantly greater number of left-side rib fractures (67%) than right-side fractures (P<0.001). Fractures were most often identified in the posterior and lateral regions and mid level of the ribcage (Ribs 5 through 8). Fifty-four percent of subjects had other skeletal fractures; these non-rib fractures were also predominantly on the left side (P=0.006). CONCLUSION: In our study of abused children, there was a higher incidence of rib fractures in the posterior, lateral and mid-level locations. Additionally, we found a predominance of left-side rib and other skeletal fractures. Further research is needed to understand whether factors such as perpetrator handedness are associated with these unequal distributions of fractures in abused children.


Assuntos
Maus-Tratos Infantis/diagnóstico , Radiografia/métodos , Fraturas das Costelas/diagnóstico por imagem , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Estudos Retrospectivos , Costelas/diagnóstico por imagem
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA