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1.
Environ Sci Technol ; 58(28): 12409-12419, 2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-38953529

RESUMO

Waste-to-energy systems can provide a functional demonstration of the economic and environmental benefits of circularity, innovation, and reimagining existing systems. This study offers a robust quantification of the greenhouse gas (GHG) emission reduction potential of the adoption of anaerobic digestion (AD) technology on applicable large-scale dairy farms in the contiguous United States. GHG reduction estimates were developed through a robust life cycle modeling framework paired with sensitivity and uncertainty analyses. Twenty dairy configurations were modeled to capture important differences in housing and manure management practices, applicable AD technologies, regional climates, storage cleanout schedules, and methods of land application. Monte Carlo results for the 90% confidence interval illustrate the potential for AD adoption to reduce GHG emissions from the large-scale dairy industry by 2.45-3.52 MMT of CO2-eq per year considering biogas use only in renewable natural gas programs and as much as 4.53-6.46 MMT of CO2-eq per year with combined heat and power as an additional biogas use case. At the farm level, AD technology may reduce GHG emissions from manure management systems by 58.1-79.8% depending on the region. Discussion focuses on regional differences in GHG emissions from manure management strategies and the challenges and opportunities surrounding AD adoption.


Assuntos
Indústria de Laticínios , Gases de Efeito Estufa , Anaerobiose , Estados Unidos , Esterco , Fazendas , Efeito Estufa , Animais
2.
mSphere ; 8(5): e0029523, 2023 10 24.
Artigo em Inglês | MEDLINE | ID: mdl-37607054

RESUMO

Co-infection with Streptococcus mutans and Candida albicans is associated with dental caries, and their co-cultivation results in enhanced biofilm matrix production that contributes to increased virulence and caries risk. Moreover, the catalase-negative S. mutans demonstrates increased oxidative stress tolerance when co-cultivated in biofilms with C. albicans, a catalase-producing yeast. Here, we sought to obtain mechanistic insights into the increased H2O2 tolerance of S. mutans when co-cultivated with clinical isolates of Candida glabrata, Candida tropicalis, and C. albicans. Additionally, the C. albicans SC5314 laboratory strain, its catalase mutant (SC5314Δcat1), and S. mutans UA159 and its glucosyltransferase B/C mutant (UA159ΔgtfB/C) were grown as single- and dual-species biofilms. Time-kill assays revealed that upon acute H2O2 challenge, the survival rates of S. mutans in dual-species biofilms with the clinical isolates and C. albicans SC5314 were greater than when paired with SC5314Δcat1 or as a single-species biofilm. Importantly, this protection was independent of glucan production through S. mutans GtfB/C. Transwell assays and treatment with H2O2-pre-stimulated C. albicans SC5314 supernatant revealed that this protection is contact-dependent. Biofilm stability assays with sublethal H2O2 or peroxigenic Streptococcus A12 challenge resulted in biomass reduction of single-species S. mutans UA159 and dual-species with SC5314Δcat1 biofilms compared to UA159 biofilms co-cultured with C. albicans SC5314. S. mutans oxidative stress genes were upregulated in single-species biofilms when exposed to H2O2, but not when S. mutans was co-cultivated with C. albicans SC5314. Here, we uncovered a novel, contact-dependent, synergistic interaction in which the catalase of C. albicans protects S. mutans against H2O2. IMPORTANCE It is well established that co-infection with the gram-positive caries-associated bacterium Streptococcus mutans and the yeast pathobiont Candida albicans results in aggressive forms of caries in humans and animal models. Together, these microorganisms form robust biofilms through enhanced production of extracellular polysaccharide matrix. Further, co-habitation in a biofilm community appears to enhance these microbes' tolerance to environmental stressors. Here, we show that catalase produced by C. albicans protects S. mutans from H2O2 stress in a biofilm matrix-independent manner. Our findings uncovered a novel synergistic trait between these two microorganisms that could be further exploited for dental caries prevention and control.


Assuntos
Coinfecção , Cárie Dentária , Animais , Humanos , Streptococcus mutans/genética , Candida albicans/genética , Peróxido de Hidrogênio/farmacologia , Catalase/genética , Biofilmes
3.
mBio ; 11(1)2020 01 14.
Artigo em Inglês | MEDLINE | ID: mdl-31937647

RESUMO

The phagocytic cells of the innate immune system are an essential first line of antimicrobial defense, and yet Candida albicans, one of the most problematic fungal pathogens, is capable of resisting the stresses imposed by the macrophage phagosome, eventually resulting in the destruction of the phagocyte. C. albicans rapidly adapts to the phagosome by upregulating multiple alternative carbon utilization pathways, particularly those for amino acids, carboxylic acids, and N-acetylglucosamine (GlcNAc). Here, we report that C. albicans recognizes these carbon sources both as crucial nutrients and as independent signals in its environment. Even in the presence of glucose, each carbon source promotes increased resistance to a unique profile of stressors; lactate promotes increased resistance to osmotic and cell wall stresses, amino acids increased resistance to oxidative and nitrosative stresses, and GlcNAc increased resistance to oxidative stress and caspofungin, while all three alternative carbon sources have been shown to induce resistance to fluconazole. Moreover, we show mutants incapable of utilizing these carbon sources, in particular, strains engineered to be defective in all three pathways, are significantly attenuated in both macrophage and mouse models, with additive effects observed as multiple carbon pathways are eliminated, suggesting that C. albicans simultaneously utilizes multiple carbon sources within the macrophage phagosome and during disseminated candidiasis. Taking the data together, we propose that, in addition to providing energy to the pathogen within host environments, alternative carbon sources serve as niche-specific priming signals that allow C. albicans to recognize microenvironments within the host and to prepare for stresses associated with that niche, thus promoting host adaptation and virulence.IMPORTANCECandida albicans is a fungal pathogen and a significant cause of morbidity and mortality, particularly in people with defects, sometimes minor ones, in innate immunity. The phagocytes of the innate immune system, particularly macrophages and neutrophils, generally restrict this organism to its normal commensal niches, but C. albicans shows a robust and multifaceted response to these cell types. Inside macrophages, a key component of this response is the activation of multiple pathways for the utilization of alternative carbon sources, particularly amino acids, carboxylic acids, and N-acetylglucosamine. These carbon sources are key sources of energy and biomass but also independently promote stress resistance, induce cell wall alterations, and affect C. albicans interactions with macrophages. Engineered strains incapable of utilizing these alternative carbon pathways are attenuated in infection models. These data suggest that C. albicans recognizes nutrient composition as an indicator of specific host environments and tailors its responses accordingly.


Assuntos
Candida albicans/imunologia , Candida albicans/metabolismo , Carbono/metabolismo , Proteínas Fúngicas/metabolismo , Macrófagos/microbiologia , Redes e Vias Metabólicas , Estresse Oxidativo , Animais , Candida albicans/patogenicidade , Linhagem Celular , Proteínas Fúngicas/genética , Glucose/metabolismo , Interações Hospedeiro-Patógeno , Camundongos , Fagossomos/metabolismo , Virulência
4.
J Healthc Inf Manag ; 21(2): 18-25, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17583164

RESUMO

Clinical decision support can be employed to increase patient safety and improve workflow efficiencies for physicians and other healthcare providers. Physician input into the design and deployment of clinical decision support systems can increase the utility of the alerts and reduce the likelihood of "alert fatigue." The Hospital for Special Surgery is a 146-bed orthopedic facility that performs approximately 18,000 surgeries a year Efficient work processes are a necessity. The facility began implementing a new electronic health record system in June 2005 and plan to go live in summer 2007. This article reports on some of the clinical decision support rules and alerts being incorporated into the facility's system in the following categories--high-risk, high-frequency scenarios, rules that provide efficiencies and value from the presciber perspective, and rules that relate to patient safety.


Assuntos
Sistemas de Apoio a Decisões Clínicas , Hospitais Especializados/normas , Equipes de Administração Institucional , Liderança , Erros Médicos/prevenção & controle , Sistemas de Registro de Ordens Médicas , Ortopedia/normas , Garantia da Qualidade dos Cuidados de Saúde/organização & administração , Gestão da Segurança/organização & administração , Difusão de Inovações , Eficiência Organizacional , Hospitais Especializados/organização & administração , Humanos , Cidade de Nova Iorque , Estudos de Casos Organizacionais , Cultura Organizacional , Objetivos Organizacionais , Estados Unidos
5.
mSphere ; 2(5)2017.
Artigo em Inglês | MEDLINE | ID: mdl-28904994

RESUMO

Phagocytosis by innate immune cells is one of the most effective barriers against the multiplication and dissemination of microbes within the mammalian host. Candida albicans, a pathogenic yeast, has robust mechanisms that allow survival upon macrophage phagocytosis. C. albicans survives in part because it can utilize the alternative carbon sources available in the phagosome, including carboxylic acids and amino acids. Furthermore, metabolism of these compounds raises the pH of the extracellular environment, which combats the acidification and maturation of the phagolysosome. In this study, we demonstrate that metabolism by C. albicans of an additional carbon source, N-acetylglucosamine (GlcNAc), facilitates neutralization of the phagosome by a novel mechanism. Catabolism of GlcNAc raised the ambient pH through release of ammonia, which is distinct from growth on carboxylic acids but similar to growth on amino acids. However, the effect of GlcNAc metabolism on pH was genetically distinct from the neutralization induced by catabolism of amino acids, as mutation of STP2 or ATO5 did not impair the effects of GlcNAc. In contrast, mutants lacking the dedicated GlcNAc transporter gene NGT1 or the enzymes responsible for catabolism of GlcNAc were defective in altering the pH of the phagosome. This correlated with reduced survival following phagocytosis and decreased ability to damage macrophages. Thus, GlcNAc metabolism represents the third genetically independent mechanism that C. albicans utilizes to combat the rapid acidification of the phagolysosome, allowing for cells to escape and propagate infection. IMPORTANCECandida albicans is the most important medically relevant fungal pathogen, with disseminated candidiasis being the fourth most common hospital-associated bloodstream infection. Macrophages and neutrophils are innate immune cells that play a key role in host defense by phagocytosing and destroying C. albicans cells. To survive this attack by macrophages, C. albicans generates energy by utilizing alternative carbon sources that are available in the phagosome. Interestingly, metabolism of amino acids and carboxylic acids by C. albicans raises the pH of the phagosome and thereby blocks the acidification of the phagosome, which is needed to initiate antimicrobial attack. In this work, we demonstrate that metabolism of a third type of carbon source, the amino sugar GlcNAc, also induces pH neutralization and survival of C. albicans upon phagocytosis. This mechanism is genetically and physiologically distinct from the previously described mechanisms of pH neutralization, indicating that the robust metabolic plasticity of C. albicans ensures survival upon macrophage phagocytosis.

6.
Psychol Rep ; 99(3): 664-70, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17305180

RESUMO

The Brief Cognitive Rating Scale facilitated observation of the preservation and decline of abilities due to dementias among 73 female and 52 male residents at nursing homes in a northeastern and southwestern state. They ranged in age from 41 to 102 years (M=78, SD = 10.5). Dementia diagnoses included presenile Alzheimers, senile Alzheimers, Vascular Dementia, Dementia secondary to Huntington's Disease, Dementia due to Pick's Disease, and Korsakoff Dementia secondary to chronic alcoholism. Their ratings on tasks of the scale were submitted to an order analysis procedure to explore the order of decline and preservation of abilities. Results for these nursing home residents show an apparent order: loss singly or concurrently of the abilities of concentration and recent memory, followed by past memory and functioning and self-care that also appeared to be unpredictably lost or preserved singly or concurrently by different individuals, and, finally, by orientation that was preserved in 82% of the subjects.


Assuntos
Aptidão , Demência/diagnóstico , Testes Neuropsicológicos , Atividades Cotidianas/psicologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Atenção , Demência/psicologia , Progressão da Doença , Feminino , Instituição de Longa Permanência para Idosos , Humanos , Masculino , Memória de Curto Prazo , Pessoa de Meia-Idade , Casas de Saúde , Orientação , Retenção Psicológica , Autocuidado/psicologia
7.
J Psychosoc Nurs Ment Health Serv ; 40(1): 40-5, 2002 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11813352

RESUMO

1. Group process can be an effective tool to cope with aggressive behaviors of nursing home residents. 2. Staff education in and commitment to group process are essential. 3. Peer pressure, therapeutic confrontation, and a supportive environment empower residents and staff to cope constructively with negative behaviors.


Assuntos
Agressão/psicologia , Educação , Processos Grupais , Transtornos Mentais/enfermagem , Casas de Saúde , Adulto , Feminino , Humanos , Masculino , Relações Enfermeiro-Paciente , Planejamento de Assistência ao Paciente
10.
Artigo em Inglês | MEDLINE | ID: mdl-19557101

RESUMO

Excited delirium, sometimes referred to as agitated or excited delirium, is the label assigned to the state of acute behavioral disinhibition manifested in a cluster of behaviors that may include bizarreness, aggressiveness, agitation, ranting, hyperactivity, paranoia, panic, violence, public disturbance, surprising physical strength, profuse sweating due to hyperthermia, respiratory arrest, and death. Excited delirium is reported to result from substance intoxication, psychiatric illness, alcohol withdrawal, head trauma, or a combination of these. This communication reviews the history of the origins of excited delirium, selected research related to its causes, symptoms, management, and the links noted between it and selected medical and psychiatric conditions. Excited delirium involves behavioral and physical symptoms that are also observed in medical and psychiatric conditions such as rhabdomyolysis, neuroleptic malignant syndrome, and catatonia. A useful contribution of this communication is that it links the state of excited delirium to conditions for which there are known and effective medical and psychiatric interventions.

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