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1.
Clin Infect Dis ; 2024 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-38867715

RESUMO

BACKGROUND: Infectious diseases (ID) physicians are increasingly faced with the challenge of caring for patients with terminal illnesses or incurable infections. METHODS: This was a retrospective cohort of all patients with an ID consult within an academic health system 1/1/2014 - 12/31/2023, including community, general, and transplant ID consult services. RESULTS: There were 60,820 inpatient ID consults (17,235 community, 29,999 general, and 13,586 transplant) involving 37,848 unique patients. The number of consults increased by 94% and the rate rose from 5.0 to 9.9 consults per 100 inpatients (p<0.001). In total, 7.5% of patients receiving an ID consult died during admission, and 1,006 (2.6%) of patients were discharged to hospice. In-hospital mortality was 5.2% for community ID, 7.8% for general ID, and 10.7% for transplant ID patients (p<0.001). Six-month mortality was 9% for all non-obstetric admissions, , vs. 19% for community ID, 20.9% for general ID, and 22.3% for transplant ID.In total 2,866 (7.6%) of all patients receiving ID consultation also received palliative care consultation during the same hospitalization. The index ID consult preceded any palliative consult in the majority (69.5%) of cases. 16.3% of patients had a do-not-resuscitate order during the index hospitalization. 12.2% of all patients with a do-not-resuscitate order had this placed on the same day as the ID consult. CONCLUSIONS: Patients receiving ID consultation were increasingly complex and more likely to die soon after consultation. These results provide a framework for ID clinicians to consider their role in end-of-life care.

2.
Clin Infect Dis ; 72(10): e604-e607, 2021 05 18.
Artigo em Inglês | MEDLINE | ID: mdl-32918071

RESUMO

BACKGROUND: Understanding the epidemiology of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is essential for public health control efforts. Social, demographic, and political characteristics at the United States (US) county level might be associated with changes in SARS-CoV-2 case incidence. METHODS: We conducted a retrospective analysis of the relationship between the change in reported SARS-CoV-2 case counts at the US county level during 1 June-30 June 2020 and social, demographic, and political characteristics of the county. RESULTS: Of 3142 US counties, 1023 were included in the analysis: 678 (66.3%) had increasing and 345 (33.7%) nonincreasing SARS-CoV-2 case counts between 1 June and 30 June 2020. In bivariate analysis, counties with increasing case counts had a significantly higher Social Deprivation Index (median, 48 [interquartile range {IQR}, 24-72]) than counties with nonincreasing case counts (median, 40 [IQR, 19-66]; P = .009). Counties with increasing case counts were significantly more likely to be metropolitan areas of 250 000-1 million population (P < .001), to have a higher percentage of black residents (9% vs 6%; P = .013), and to have voted for the Republican presidential candidate in 2016 by a ≥10-point margin (P = .044). In the multivariable model, metropolitan areas of 250 000-1 million population, higher percentage of black residents, and a ≥10-point Republican victory were independently associated with increasing case counts. CONCLUSIONS: Increasing case counts of SARS-CoV-2 in the US during June 2020 were associated with a combination of sociodemographic and political factors. Addressing social disadvantage and differential belief systems that may correspond with political alignment will play a critical role in pandemic control.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , Pandemias , Política , Estudos Retrospectivos , Estados Unidos/epidemiologia
3.
Artigo em Inglês | MEDLINE | ID: mdl-30642941

RESUMO

Treatment options for drug-resistant cytomegalovirus (CMV) are limited. Letermovir is a novel antiviral recently approved for CMV prophylaxis following hematopoietic cell transplantation, but its efficacy in other settings is unknown. We recently used letermovir for salvage treatment in four solid organ transplant recipients with ganciclovir-resistant CMV retinitis. All patients improved clinically without known adverse drug events. However, three patients failed to maintain virologic suppression, including two patients who developed genotypically confirmed resistance to letermovir while on therapy.


Assuntos
Acetatos/uso terapêutico , Antivirais/uso terapêutico , Retinite por Citomegalovirus/tratamento farmacológico , Citomegalovirus/efeitos dos fármacos , Quinazolinas/uso terapêutico , Citomegalovirus/genética , Farmacorresistência Viral , Ganciclovir/farmacologia , Humanos , Transplante de Órgãos/efeitos adversos , Terapia de Salvação , Transplantados
4.
Transpl Infect Dis ; 20(4): e12902, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29668123

RESUMO

BACKGROUND: Nocardia are uncommon pathogens that disproportionately afflict the immunocompromised host. Epidemiology and outcome data of Nocardia infections in transplant recipients are limited. METHODS: We performed a retrospective chart review of all patients at Duke University Hospital with a history of solid organ transplant (SOT) or hematopoietic cell transplant (HCT) and at least one positive culture for Nocardia between 1996 and 2013. Our aim was to describe the epidemiology and outcomes of Nocardia infections in the transplanted host. RESULTS: During the 18-year study period, 51 patients (14 HCT and 37 SOT recipients) had Nocardia infection. Nocardia incidence was stable during the study period in all populations except heart transplants, whose incidence declined. Infection occurred earlier in the HCT group than the SOT group (median time to diagnosis of 153 and 370 days, respectively). In both groups, the most common site involved was the lung. Outcomes were overall poor, especially in the HCT group with a cure rate of 29%. Heart transplant recipients had significantly better overall survival (P < .05) than other patients. Trimethoprim-sulfamethoxazole (TMP-SMX) prophylaxis did not provide complete protection from Nocardia infections, nor did it appear to select for resistant Nocardia isolates. CONCLUSIONS: Infections with Nocardia are typically a late post-transplant complication. The use of TMP-SMX prophylaxis was not associated with TMP-SMX-resistant Nocardia. Overall outcomes remain poor.


Assuntos
Antibioticoprofilaxia , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Hospedeiro Imunocomprometido , Nocardiose/epidemiologia , Transplante de Órgãos/efeitos adversos , Adolescente , Adulto , Idoso , Antibacterianos/uso terapêutico , Criança , Pré-Escolar , Feminino , Humanos , Incidência , Lactente , Masculino , Pessoa de Meia-Idade , Nocardia/isolamento & purificação , Nocardiose/imunologia , Nocardiose/microbiologia , Estudos Retrospectivos , Fatores de Risco , Resultado do Tratamento , Combinação Trimetoprima e Sulfametoxazol/uso terapêutico , Adulto Jovem
5.
Aesthet Surg J ; 43(3): 389-391, 2023 02 21.
Artigo em Inglês | MEDLINE | ID: mdl-36514920
6.
Proc Natl Acad Sci U S A ; 111(36): 12986-91, 2014 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-25157162

RESUMO

Rock art compels interest from both researchers and a broader public, inspiring many hypotheses about its cultural origin and meaning, but it is notoriously difficult to date numerically. Barrier Canyon-style (BCS) pictographs of the Colorado Plateau are among the most debated examples; hypotheses about its age span the entire Holocene epoch and previous attempts at direct radiocarbon dating have failed. We provide multiple age constraints through the use of cross-cutting relations and new and broadly applicable approaches in optically stimulated luminescence dating at the Great Gallery panel, the type section of BCS art in Canyonlands National Park, southeastern Utah. Alluvial chronostratigraphy constrains the burial and exhumation of the alcove containing the panel, and limits are also set by our related research dating both a rockfall that removed some figures and the rock's exposure duration before that time. Results provide a maximum possible age, a minimum age, and an exposure time window for the creation of the Great Gallery panel, respectively. The only prior hypothesis not disproven is a late Archaic origin for BCS rock art, although our age result of A.D. ∼ 1-1100 coincides better with the transition to and rise of the subsequent Fremont culture. This chronology is for the type locality only, and variability in the age of other sites is likely. Nevertheless, results suggest that BCS rock art represents an artistic tradition that spanned cultures and the transition from foraging to farming in the region.


Assuntos
Sedimentos Geológicos , Luminescência , Datação Radiométrica/métodos , Radioisótopos de Carbono , Geografia , Fatores de Tempo
7.
Emerg Infect Dis ; 19(3): 365-70, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23628077

RESUMO

Nontuberculous mycobacteria are increasingly associated with cutaneous infections after cosmetic procedures. Fractionated CO2 resurfacing, a widely used technique for photorejuvenation, has been associated with a more favorable side effect profile than alternative procedures. We describe 2 cases of nontuberculous mycobacterial infection after treatment with a fractionated CO2 laser at a private clinic. Densely distributed erythematous papules and pustules developed within the treated area within 2 weeks of the laser procedure. Diagnosis was confirmed by histologic analysis and culture. Both infections responded to a 4-month course of a multidrug regimen. An environmental investigation of the clinic was performed, but no source of infection was found. The case isolates differed from each other and from isolates obtained from the clinic, suggesting that the infection was acquired by postprocedure exposure. Papules and pustules after fractionated CO2 resurfacing should raise the suspicion of nontuberculous mycobacterial infection.


Assuntos
Técnicas Cosméticas/efeitos adversos , Terapia com Luz de Baixa Intensidade/efeitos adversos , Infecções por Mycobacterium não Tuberculosas/diagnóstico , Dermatopatias Bacterianas/diagnóstico , Antibacterianos/uso terapêutico , Quimioterapia Combinada , Feminino , Humanos , Pessoa de Meia-Idade , Infecções por Mycobacterium não Tuberculosas/tratamento farmacológico , Infecções por Mycobacterium não Tuberculosas/microbiologia , Dermatopatias Bacterianas/tratamento farmacológico , Dermatopatias Bacterianas/microbiologia
8.
Sex Transm Dis ; 40(11): 839-41, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24113403

RESUMO

The impact of syphilis reverse sequence screening has not been evaluated in community outreach. Using reverse sequence screening in neighborhoods identified with geographic information systems, we found that among 239 participants, 45 (19%) were seropositive. Of these, 3 (7%) had untreated syphilis, 33 (73%) had previously treated syphilis infection, and 9 (20%) had negative nontreponemal test results.


Assuntos
Algoritmos , Programas de Rastreamento/métodos , Sorodiagnóstico da Sífilis/métodos , Sífilis/diagnóstico , Treponema pallidum/isolamento & purificação , Adulto , Relações Comunidade-Instituição , Estudos de Viabilidade , Feminino , Seguimentos , Sistemas de Informação Geográfica , Humanos , Masculino , North Carolina/epidemiologia , Sensibilidade e Especificidade , Sífilis/epidemiologia
9.
Health Secur ; 21(5): 358-370, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37581881

RESUMO

In response to the COVID-19 pandemic, the University of Oklahoma Hudson College of Public Health launched the Achieving a Healthy Oklahoma (AHO) initiative in 2021. The goals of AHO were to assess lessons learned in Oklahoma from COVID-19 and set the foundation for enhanced public-private community collaboration by developing recommendations to prepare for future public health crises and promote health across all major economic sectors. Over 700 stakeholders were engaged in surveys, interviews, workgroup meetings, community listening sessions, and steering committee meetings over 8 months to accomplish these goals. Stakeholders produced 60 sector- and stakeholder-specific policy recommendations to address the major issues uncovered during the initiative. The AHO team then distilled them into 5 recommendations: (1) invest in the future of Oklahoma's health workforce to include critically needed public health professions in Oklahoma's healthcare loan repayment programs; (2) establish contracts between higher education institutions in Oklahoma and state and local health departments to monitor health sector workforce needs and provide training; (3) strengthen the delivery of coordinated public health services within local communities during emergencies and daily operations by dedicating health department roles to coordinate public health projects and services; (4) improve preparedness by coordinating annual emergency management exercises across local and state health departments; and (5) emphasize the efficiency and effectiveness of cross-sector collaborative efforts between public, private, and tribal partners. The AHO initiative serves as an action guide for assessing and improving state-level public health emergency responses and strengthening public health infrastructure. Implementing the recommendations in Oklahoma and assessing and addressing similar needs across the nation are necessary to prepare the United States for future public health emergencies.

10.
Open Forum Infect Dis ; 10(8): ofad381, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37539060

RESUMO

Coinfection with sexually transmitted infections (STIs) and mpox is common. We evaluated concurrent STI testing among Duke Health patients tested for mpox. We found that most patients tested for mpox were not comprehensively tested for STIs, despite concurrent STIs being diagnosed in 15% of patients when testing was performed.

11.
Open Forum Infect Dis ; 10(9): ofad434, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37662451

RESUMO

Background: The 2022 mpox outbreak disproportionately affected men who have sex with men and persons living with HIV (PLWH). A 2-dose mpox vaccine series was deployed in mid-2022. Structural racism and insurance status may have affected equitable vaccination. Methods: We defined 3 cohorts: PLWH with at least 1 clinic visit between 1 July 2021 and 1 July 2022 (n = 2066), HIV preexposure prophylaxis (PrEP) recipients as of 1 January 2022 (n = 262), and all mpox-vaccinated patients in our health system between 1 July 2022 and 30 November 2022 (n = 807). We identified patients with prior diagnosed sexually transmitted infections (STIs) as having a positive test result for gonorrhea, chlamydia, or syphilis between 1 July 2021-1 July 2022. The primary outcome was receipt of at least 1 dose of mpox vaccine. Results: We identified 224 (10.8%) PLWH and 50 (19.0%) PrEP patients who received at least 1 dose of mpox vaccine. Among PLWH, White race (odds ratio [OR], 1.55; 95% CI, 1.11-2.16), private insurance (OR, 1.83; 95% CI, 1.01-3.34), prior STI (OR, 3.04; 95% CI, 2.16-4.27), prior COVID-19 vaccination (OR, 3.17; 95% CI, 1.93-5.20), and prior influenza vaccination (OR, 1.42; 95% CI, 1.30-1.96) independently predicted mpox vaccination. Within the PrEP cohort, prior COVID-19 vaccination and seasonal influenza vaccination predicted mpox vaccination. Uninsured patients were vaccinated later in the outbreak than patients with private insurance (median time to vaccination, 41 days in the privately insured group vs 83 days in the uninsured group; P < .0001). Conclusions: Race, insurance status, prior STI, and previous receipt of other vaccines influenced uptake of mpox vaccine. Addressing health disparities and vaccine acceptance will be essential in improving future outbreak response.

13.
Clin Infect Dis ; 53(8): 787-92, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21921222

RESUMO

BACKGROUND: Pedicure-associated nontuberculous mycobacterial furunculosis has been reported in the setting of either outbreaks or sporadic case reports. The epidemiology of these infections is not well understood. METHODS: Systematic surveillance for pedicure-associated nontuberculous mycobacterial furunculosis was conducted in 2 North Carolina counties from 1 January 2005 through 31 December 2008. A subset of implicated nail salons and control salons was inspected and sampled for nontuberculous mycobacteria. RESULTS: Forty cases of suspected or confirmed pedicure-associated nontuberculous mycobacterial furunculosis were reported during the 4-year study period. Furunculosis incidence in the surveillance region was 1.00, 0.96, 0.83, and 0.89 cases per 100,000 population in 2005, 2006, 2007, and 2008, respectively. The responsible organisms primarily belonged to the Mycobacterium chelonae/abscessus group (30 [91%] of 33 isolates). Thirteen implicated salons and 11 control salons were visited and environmentally sampled. An assortment of nontuberculous mycobacteria was cultured from footbaths, but there was no association between the species distribution of the environmental isolates and implication of the salon in human infection. Evidence of suboptimal cleaning (visible debris or surface biofilms) was observed in at least 1 footbath for 11 of 13 implicated salons and 4 of 11 control salons (P = .032). CONCLUSIONS: Pedicure-associated mycobacterial furunculosis was endemic in these 2 North Carolina counties during 2005-2008. Suboptimal footbath cleaning may have contributed to these infections, which suggests straightforward means of potential prevention. The relative rarity of this type of infection in the setting of nearly ubiquitous exposure to these pathogens suggests that as yet undefined host-specific or procedure-related factors may be involved in susceptibility to these infections.


Assuntos
Furunculose/epidemiologia , Hidroterapia/efeitos adversos , Infecções por Mycobacterium não Tuberculosas/epidemiologia , Micobactérias não Tuberculosas/isolamento & purificação , Adolescente , Adulto , Indústria da Beleza , Doenças Endêmicas , Feminino , Furunculose/microbiologia , Furunculose/transmissão , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Infecções por Mycobacterium não Tuberculosas/microbiologia , Infecções por Mycobacterium não Tuberculosas/transmissão , Mycobacterium chelonae/isolamento & purificação , North Carolina/epidemiologia , Vigilância da População , Fatores de Risco , Adulto Jovem
14.
BMC Infect Dis ; 11: 305, 2011 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-22047015

RESUMO

BACKGROUND: Community-based screening for TB, combined with HIV and syphilis testing, faces a number of barriers. One significant barrier is the value that target communities place on such screening. METHODS: Integrated testing for TB, HIV, and syphilis was performed in neighborhoods identified using geographic information systems-based disease mapping. TB testing included skin testing and interferon gamma release assays. Subjects completed a survey describing disease risk factors, healthcare access, healthcare utilization, and willingness to pay for integrated testing. RESULTS: Behavioral and social risk factors among the 113 subjects were prevalent (71% prior incarceration, 27% prior or current crack cocaine use, 35% homelessness), and only 38% had a regular healthcare provider. The initial 24 subjects reported that they would be willing to pay a median $20 (IQR: 0-100) for HIV testing and $10 (IQR: 0-100) for TB testing when the question was asked in an open-ended fashion, but when the question was changed to a multiple-choice format, the next 89 subjects reported that they would pay a median $5 for testing, and 23% reported that they would either not pay anything to get tested or would need to be paid $5 to get tested for TB, HIV, or syphilis. Among persons who received tuberculin skin testing, only 14/78 (18%) participants returned to have their skin tests read. Only 14/109 (13%) persons who underwent HIV testing returned to receive their HIV results. CONCLUSION: The relatively high-risk persons screened in this community outreach study placed low value on testing. Reported willingness to pay for such testing, while low, likely overestimated the true willingness to pay. Successful TB, HIV, and syphilis integrated testing programs in high risk populations will likely require one-visit diagnostic testing and incentives.


Assuntos
Técnicas de Laboratório Clínico/economia , Técnicas de Laboratório Clínico/métodos , Infecções por HIV/diagnóstico , Aceitação pelo Paciente de Cuidados de Saúde/estatística & dados numéricos , Sífilis/diagnóstico , Tuberculose/diagnóstico , Adulto , Feminino , Infecções por HIV/economia , Humanos , Testes de Liberação de Interferon-gama/economia , Testes de Liberação de Interferon-gama/métodos , Masculino , Pessoa de Meia-Idade , Inquéritos e Questionários , Sífilis/economia , Teste Tuberculínico/economia , Teste Tuberculínico/métodos , Tuberculose/economia
15.
J Clin Microbiol ; 48(2): 650-3, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20007390

RESUMO

Botulism developed in a patient following surgical repair of an open radial fracture. Symptoms resolved after treatment with antitoxin and antibiotics, and hardware excision was deferred. Subsequent osteomyelitis necessitated hardware exchange, and wound cultures grew Clostridium argentinense. This case highlights the management of botulism associated with orthopedic hardware.


Assuntos
Botulismo/diagnóstico , Clostridium/isolamento & purificação , Fraturas Ósseas/complicações , Fraturas Ósseas/cirurgia , Fraturas Expostas/complicações , Fraturas Expostas/cirurgia , Infecção dos Ferimentos/microbiologia , Adulto , Antibacterianos/uso terapêutico , Antitoxina Botulínica/uso terapêutico , Botulismo/microbiologia , Humanos , Masculino , Osteomielite/cirurgia , Infecções Relacionadas à Prótese
16.
PLoS One ; 15(11): e0242055, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33166372

RESUMO

BACKGROUND: Novel approaches are required to better focus latent tuberculosis infection (LTBI) efforts in low-prevalence regions. Geographic information systems, used within large health systems, may provide one such approach. METHODS: A retrospective, cross-sectional design was used to integrate US Census and Duke Health System data between January 1, 2010 and October 31, 2017 and examine the relationships between LTBI screening and population tuberculosis risk (assessed using the surrogate measure of proportion of persons born in tuberculosis-endemic regions) by census tract. RESULTS: The median proportion of Duke patients screened per census tract was 0.01 (range 0-0.1, interquartile range 0.01-0.03). The proportion of Duke patients screened within a census tract significantly but weakly correlated with the population risk. Furthermore, patients residing in census tracts with higher population tuberculosis risk were more likely to be screened with TST than with an IGRA (p<0.001). CONCLUSION: The weak correlation between patient proportion screened for LTBI and our surrogate marker of population tuberculosis risk suggests that LTBI screening efforts should be better targeted. This type of geography-based analysis may serve as an easily obtainable benchmark for LTBI screening in health systems with low tuberculosis prevalence.


Assuntos
Tuberculose Latente/diagnóstico , Estudos Transversais , Doenças Endêmicas , Geografia Médica , Humanos , Tuberculose Latente/epidemiologia , Prevalência , Estudos Retrospectivos , Fatores de Risco
17.
Mol Biol Cell ; 17(2): 667-79, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16291861

RESUMO

The Galpha protein Gpa1 governs the cAMP-PKA signaling pathway and plays a central role in virulence and differentiation in the human fungal pathogen Cryptococcus neoformans, but the signals and receptors that trigger this pathway were unknown. We identified seven putative proteins that share identity with known G protein-coupled receptors (GPCRs). One protein, Gpr4, shares limited sequence identity with the Dictyostelium discoideum cAMP receptor cAR1 and the Aspergillus nidulans GPCR protein GprH and also shares structural similarity with the Saccharomyces cerevisiae receptor Gpr1. gpr4 mutants exhibited reduced capsule production and mating defects, similar to gpa1 mutants, and exogenous cAMP suppressed both gpr4 mutant phenotypes. Epistasis analysis provides further evidence that Gpr4 functions upstream of the Galpha subunit Gpa1. Gpr4-Gpr4 homomeric interactions were observed in the yeast two-hybrid assay, and Gpr4 was shown to physically interact with Gpa1 in the split-ubiquitin system. A Gpr4::DsRED fusion protein was localized to the plasma membrane and methionine was found to trigger receptor internalization. The analysis of intracellular cAMP levels showed that gpr4 mutants still respond to glucose but not to certain amino acids, such as methionine. Amino acids might serve as ligands for Gpr4 and could contribute to engage the cAMP-PKA pathway. Activation of the cAMP-PKA pathway by glucose and amino acids represents a nutrient coincidence detection system shared in other pathogenic fungi.


Assuntos
Aminoácidos/metabolismo , Cryptococcus neoformans/metabolismo , Proteínas Quinases Dependentes de AMP Cíclico/metabolismo , AMP Cíclico/metabolismo , Proteínas Fúngicas/fisiologia , Receptores Acoplados a Proteínas G/fisiologia , Cryptococcus neoformans/patogenicidade , Dimerização , Epistasia Genética , Ligantes , Melaninas/biossíntese , Metionina/metabolismo , Modelos Biológicos , Filogenia , Conformação Proteica , Proteínas Recombinantes de Fusão/análise , Homologia de Sequência de Aminoácidos , Transdução de Sinais
18.
Mol Biol Cell ; 17(7): 3122-35, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16672377

RESUMO

The stress-activated mitogen-activated protein kinase (MAPK) pathway is widely used by eukaryotic organisms as a central conduit via which cellular responses to the environment effect growth and differentiation. The basidiomycetous human fungal pathogen Cryptococcus neoformans uniquely uses the stress-activated Pbs2-Hog1 MAPK system to govern a plethora of cellular events, including stress responses, drug sensitivity, sexual reproduction, and virulence. Here, we characterized a fungal "two-component" system that controls these fundamental cellular functions via the Pbs2-Hog1 MAPK cascade. A typical response regulator, Ssk1, modulated all Hog1-dependent phenotypes by controlling Hog1 phosphorylation, indicating that Ssk1 is the major upstream signaling component of the Pbs2-Hog1 pathway. A second response regulator, Skn7, governs sensitivity to Na+ ions and the antifungal agent fludioxonil, negatively controls melanin production, and functions independently of Hog1 regulation. To control these response regulators, C. neoformans uses multiple sensor kinases, including two-component-like (Tco) 1 and Tco2. Tco1 and Tco2 play shared and distinct roles in stress responses and drug sensitivity through the Hog1 MAPK system. Furthermore, each sensor kinase mediates unique cellular functions for virulence and morphological differentiation. Our findings highlight unique adaptations of this global two-component MAPK signaling cascade in a ubiquitous human fungal pathogen.


Assuntos
Cryptococcus neoformans/patogenicidade , Proteínas Fúngicas/metabolismo , Quinases de Proteína Quinase Ativadas por Mitógeno/metabolismo , Fatores de Transcrição/metabolismo , Fatores de Virulência/metabolismo , Cryptococcus neoformans/enzimologia , Cryptococcus neoformans/crescimento & desenvolvimento , Farmacorresistência Fúngica , Proteínas Fúngicas/genética , Melaninas/biossíntese , Quinases de Proteína Quinase Ativadas por Mitógeno/genética , Fenótipo , Fosforilação , Reprodução/genética , Transdução de Sinais , Fatores de Transcrição/genética , Virulência/genética , Fatores de Virulência/genética
19.
Case Rep Infect Dis ; 2019: 8109280, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31143483

RESUMO

We present the case of a 92-year-old man with septic arthritis of a prosthetic hip joint due to Streptococcus salivarius one week following a high-risk dental procedure despite preprocedure amoxicillin. S. salivarius is a commensal bacterium of the human oral mucosa that is an uncommon cause of bacteremia. S. salivarius has previously been described as a causative agent of infective endocarditis and spontaneous bacterial peritonitis but was only recently recognized as a cause of prosthetic joint infection. This case highlights the potential pathogenicity of a common commensal bacteria and the questionable utility of prophylactic antibiotics before dental procedures to prevent periprosthetic joint infections.

20.
Curr Biol ; 15(22): 2013-20, 2005 Nov 22.
Artigo em Inglês | MEDLINE | ID: mdl-16303560

RESUMO

The gas carbon dioxide (CO2) plays a critical role in microbial and mammalian respiration, photosynthesis in algae and plants, chemoreception in insects, and even global warming . However, how CO2 is transported, sensed, and metabolized by microorganisms is largely not understood. For instance, CO2 is known to induce production of polysaccharide capsule virulence determinants in pathogenic bacteria and fungi via unknown mechanisms . Therefore, we studied CO2 actions in growth, differentiation, and virulence of the basidiomycetous human fungal pathogen Cryptococcus neoformans. The CAN2 gene encoding beta-carbonic anhydrase in C. neoformans was found to be essential for growth in environmental ambient conditions but dispensable for in vivo proliferation and virulence at the high CO2 levels in the host. The can2Delta mutant in vitro growth defect is largely attributable to defective fatty acid synthesis. CO2 was found to inhibit cell-cell fusion but not filamentation during sexual reproduction. The can2 mutation restored early mating events in high CO2 but not later steps (fruiting body formation, sporulation), indicating a major role for carbonic anhydrase and CO2/HCO3- in this developmental cascade leading to the production of infectious spores. Our studies illustrate diverse roles of an ancient enzyme class in enabling environmental survival of a ubiquitous human pathogen.


Assuntos
Dióxido de Carbono/metabolismo , Anidrases Carbônicas/metabolismo , Cryptococcus neoformans/crescimento & desenvolvimento , Cryptococcus neoformans/patogenicidade , Esporos Fúngicos/fisiologia , Sequência de Bases , Bicarbonatos/metabolismo , Northern Blotting , Dióxido de Carbono/toxicidade , Anidrases Carbônicas/genética , Adesão Celular/efeitos dos fármacos , Biologia Computacional , Cryptococcus neoformans/genética , Cryptococcus neoformans/metabolismo , Análise Mutacional de DNA , Ácidos Graxos/biossíntese , Dados de Sequência Molecular , Mutação/genética , Reprodução/efeitos dos fármacos , Análise de Sequência de DNA , Esporos Fúngicos/efeitos dos fármacos
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