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1.
J Therm Biol ; 116: 103670, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37536102

RESUMO

Animals are increasingly exposed to potential stressors related to environmental change, and multiple stressors may alter the dynamics by which animals acquire resources and invest those resources into important life-history traits. Stress may lead to the prioritization of current reproduction to maximize lifetime reproduction (i.e., terminal investment [TI]) or, in contrast, prioritize somatic investment over current reproduction to facilitate future reproductive opportunities (i.e., reproductive restraint [RR]). Tests of the TI and RR hypotheses typically use immune challenges as stressors, and have not been explicitly tested in the context of environmental change even though warming influences resource allocation patterns across taxa. Further, the multiple-stressor framework has been a useful construct to clarify the costs of complex environmental shifts to animals, but it has not been leveraged to understand such effects on investment strategy. Thus, we tested the TI and RR hypotheses by manipulating widespread features of environmental change-glyphosate-based herbicide (GBH; Roundup®) exposure and a simulated heat wave-in the variable field cricket (Gryllus lineaticeps). A simulated heat wave affected the life-history tradeoff between investment into reproduction and soma. Specifically, heat wave prioritized investment into ovary mass over non-reproductive tissue, even after accounting for food consumption, in support of the TI hypothesis. In contrast, GBH exposure did not affect any measured trait, and crickets did not discriminate between tap water and GBH solution during drinking. Therefore, some-but not all-aspects of environmental change may alter resource investment strategies in animals. We encourage continued integration of the multiple-stressor framework and life-history theory to better understand how animals respond to their rapidly changing environments.


Assuntos
Herbicidas , Características de História de Vida , Animais , Feminino , Herbicidas/toxicidade , Temperatura Alta , Reprodução , Insetos
3.
J Hosp Infect ; 124: 37-46, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35339638

RESUMO

BACKGROUND: The COVID-19 pandemic increased the use of broad-spectrum antibiotics due to diagnostic uncertainty, particularly in critical care. Multi-professional communication became more difficult, weakening stewardship activities. AIM: To determine changes in bacterial co-/secondary infections and antibiotics used in COVID-19 patients in critical care, and mortality rates, between the first and second waves. METHODS: Prospective audit comparing bacterial co-/secondary infections and their treatment during the first two waves of the pandemic in a single-centre teaching hospital intensive care unit. Data on demographics, daily antibiotic use, clinical outcomes, and culture results in patients diagnosed with COVID-19 infection were collected over 11 months. FINDINGS: From March 9th, 2020 to September 2nd, 2020 (Wave 1), there were 156 patients and between September 3rd, 2020 and February 1st, 2021 (Wave 2) there were 235 patients with COVID-19 infection admitted to intensive care. No significant difference was seen in mortality or positive blood culture rates between the two waves. The proportion of patients receiving antimicrobial therapy (93.0% vs 81.7%; P < 0.01) and the duration of meropenem use (median (interquartile range): 5 (2-7) vs 3 (2-5) days; P = 0.01) was lower in Wave 2. However, the number of patients with respiratory isolates of Pseudomonas aeruginosa (4/156 vs 21/235; P < 0.01) and bacteraemia from a respiratory source (3/156 vs 20/235; P < 0.01) increased in Wave 2, associated with an outbreak of infection. There was no significant difference between waves with respect to isolation of other pathogens. CONCLUSION: Reduced broad-spectrum antimicrobial use in the second wave of COVID-19 compared with the first wave was not associated with significant change in mortality.


Assuntos
Anti-Infecciosos , Infecções Bacterianas , Tratamento Farmacológico da COVID-19 , Coinfecção , Antibacterianos/uso terapêutico , Anti-Infecciosos/uso terapêutico , Infecções Bacterianas/epidemiologia , Coinfecção/tratamento farmacológico , Humanos , Unidades de Terapia Intensiva , Pandemias , SARS-CoV-2
4.
Public Health Pract (Oxf) ; 2: 100069, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36101596

RESUMO

Objectives: This study aims to examine the correlation between the different types of migrant acculturation strategies according to Berry's model of acculturation (integration, assimilation, separation, and marginalisation) and their effects on mental health conditions, such as depression, anxiety and PTSD. Study design: Systematic Review. Methods: Three databases (PubMed, Ovid and Ebsco) were searched using different combinations of search terms to identify relevant articles to be included. The search terms were pre-identified using relevant synonyms for "migrants", "mental health" and "integration". The list of article titles from these searches were then filtered using predefined inclusion and exclusion criteria. The mental health consequences included a range of common conditions including suicide/self-harm, depressive disorders, psychosis, as well as substance misuse. Results: 21 primary studies were included in the review, which assessed 61,885 migrants in total (Fig. 1 and Supplemental File 1). Of these, seven were cohort studies and fourteen were cross-sectional studies.Most studies showed that marginalisation was associated with worse depression symptoms, compared to integration, assimilation and separation, while integration was associated with the least depressive symptoms.Marginalisation more than triples the likelihood of anxiety-related symptoms compared to integration. Similarly, separation increased the likelihood of anxiety-related symptoms nearly six-fold. Conclusions: Our review found out that marginalisation had the worst effects on mental health of the migrant populations while integration had the most positive effects. The study also identified three key sources which may contribute to acculturation stress and worse mental health: low education or skill set, proficiency of the host country's language, and financial hardships.

6.
Am J Transplant ; 6(11): 2535-42, 2006 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16939521

RESUMO

Thirty to fifty percent of kidney transplant recipients have glomerular diseases as the underlying causes of end-stage renal failure. While recurrence of glomerulonephritis is an important cause of late renal allograft failure, the risk factors for recurrence are largely unknown or imprecise and prediction remains difficult. Recurrent disease usually presents with similar manifestations as the native disease. With regard to treatment of recurrent glomerular disease in the renal allograft, plasma exchange may be effective in reducing proteinuria in patients with early recurrence of focal and segmental glomerulosclerosis, but immunosuppressive therapy is generally ineffective in the prevention or treatment of recurrent disease. General supportive measures including strict blood pressure control and inhibition or blockade of the rennin-angiotensin pathway are helpful in retarding the rate of deterioration in renal allograft function. Despite the risk of recurrence, kidney transplantation following primary glomerulonephritides enjoys graft and patient survival rates comparable to other causes of end-stage renal failure. With a few exceptions, living related renal transplantation is not contraindicated in view of the favorable outcome and the donor shortage. This review discusses commonly encountered recurrent glomerulonephritides, with special emphasis on the influence of post-transplant prophylactic immunosuppression and emerging treatments.


Assuntos
Glomerulonefrite/cirurgia , Transplante de Rim , Nefropatias Diabéticas/cirurgia , Glomerulonefrite/classificação , Glomerulonefrite/epidemiologia , Glomerulonefrite por IGA/cirurgia , Glomerulonefrite Membranoproliferativa/cirurgia , Glomerulonefrite Membranosa/cirurgia , Glomerulosclerose Segmentar e Focal/cirurgia , Transplante de Rim/efeitos adversos , Lúpus Eritematoso Sistêmico/cirurgia , Complicações Pós-Operatórias/epidemiologia , Recidiva
8.
Intern Med J ; 33(7): 314-6, 2003 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12823678

RESUMO

Star fruit, belonging to the Oxalidaceae family, species Averrhoa carambola, is a popular fruit among Orientals. There have been reports of hiccup, confusion, and occasional fatal outcomes in uraemic patients after ingestion of star fruit. An excitatory neurotoxin from star fruit has been implicated although the exact nature of this toxic substance has not been identified. A group of seven patients is described from the dialysis centres at Queen Mary and Tung Wah Hospitals who developed symptoms including hiccup, confusion, vomiting, impaired consciousness, muscle twitching and hyperkalaemia shortly after ingestion of star fruit. Symptoms of most patients resolved after intensified dialysis or spontaneously, and no mortality was observed. The close temporal relationship of ingestion of star fruit and onset of symptoms strongly suggests the existence of a causal relationship between the two. It is recommended that uraemic patients should totally abstain from star fruit due to these rare but potentially fatal complications. The clinical manifestations of other reported series and current evidence for the possible candidate(s) of the neurotoxin are discussed.


Assuntos
Frutas/intoxicação , Síndromes Neurotóxicas/etiologia , Intoxicação por Plantas/complicações , Intoxicação por Plantas/diagnóstico , Uremia/complicações , Injúria Renal Aguda/complicações , Injúria Renal Aguda/diagnóstico , Injúria Renal Aguda/terapia , Adulto , Idoso , Feminino , Seguimentos , Hong Kong , Humanos , Testes de Função Renal , Masculino , Pessoa de Meia-Idade , Neurotoxinas/efeitos adversos , Intoxicação por Plantas/mortalidade , Diálise Renal , Medição de Risco , Estudos de Amostragem , Índice de Gravidade de Doença , Análise de Sobrevida , Resultado do Tratamento , Uremia/diagnóstico , Uremia/mortalidade , Uremia/terapia
10.
Am J Kidney Dis ; 38(5): 1055-60, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11684559

RESUMO

A retrospective study of the prevalence and pattern of tuberculosis in patients undergoing continuous ambulatory peritoneal dialysis (CAPD) was performed. Thirty-eight cases of tuberculosis were diagnosed among 790 patients (18 men, 20 women; mean age, 58 +/- 12.6 years) between July 1994 and June 2000. The interval between the initiation of CAPD and onset of tuberculosis ranged from 1 to 168 months (median, 22 months). There were 18 cases of pulmonary tuberculosis, 14 cases of tuberculous peritonitis, 5 cases of tuberculous lymphadenitis, and 1 case of tuberculous synovitis. Patients with pulmonary tuberculosis usually presented with fever, constitutional symptoms, and pleural effusion or pulmonary infiltrates on chest radiograph. Abdominal pain and turbid dialysate were the main presenting symptoms in patients with tuberculous peritonitis. Diagnosis was established by positive culture in 20 patients, typical histological characteristics on a tissue biopsy specimen in 10 patients, and response to empirical antituberculous treatment in 8 patients. The duration of symptoms before the diagnosis of tuberculosis and initiation of antituberculous treatment ranged from 7 to 57 days (median, 30 days). Antituberculous treatment consisted of isoniazid, rifampicin, pyrazinamide, and ofloxacin for 9 to 15 months. Antituberculous treatment generally was well tolerated. Twenty-seven patients (71%) completed antituberculous treatment. No recurrence of tuberculosis was observed after a mean follow-up of 19.8 months. Eleven patients (29%) died while on antituberculous treatment; none of the deaths appeared to be directly caused by tuberculosis. We conclude that: (1) tuberculosis is prevalent among CAPD patients in our locality; (2) extrapulmonary tuberculosis, particularly tuberculous peritonitis, is common; and (3) a high index of suspicion for tuberculosis among CAPD patients is warranted to ensure early diagnosis and prompt initiation of treatment.


Assuntos
Falência Renal Crônica/complicações , Mycobacterium tuberculosis/isolamento & purificação , Diálise Peritoneal Ambulatorial Contínua , Tuberculose/complicações , Idoso , Antituberculosos/uso terapêutico , Feminino , Hong Kong , Humanos , Falência Renal Crônica/terapia , Masculino , Pessoa de Meia-Idade , Mycobacterium tuberculosis/efeitos dos fármacos , Peritonite Tuberculosa/complicações , Peritonite Tuberculosa/tratamento farmacológico , Peritonite Tuberculosa/mortalidade , Taxa de Sobrevida , Resultado do Tratamento , Tuberculose/tratamento farmacológico , Tuberculose/mortalidade , Tuberculose dos Linfonodos/complicações , Tuberculose dos Linfonodos/tratamento farmacológico , Tuberculose dos Linfonodos/mortalidade , Tuberculose Pulmonar/complicações , Tuberculose Pulmonar/tratamento farmacológico , Tuberculose Pulmonar/mortalidade
11.
J Biol Chem ; 276(42): 38665-72, 2001 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-11514536

RESUMO

Both cell-specific and ubiquitous transcription factors in fibroblasts have been identified as critical for expression of the Col1a1 gene, which encodes the alpha1 chain of type I collagen. Here, we report that Yin Yang 1 (YY1) binds to the Col1a1 promoter immediately upstream of the TATA box, and we examine the functional implications of YY1 binding for regulation of Col1a1 gene expression in BALBc/3T3 fibroblasts. The Col1a1 promoter region spanning base pairs (bp) -56 to -9 bound purified recombinant YY1 and the corresponding binding activity in nuclear extracts was supershifted using a YY1-specific antibody. Mutation of the TATA box to TgTA enhanced YY1 complex formation. Mutation analysis revealed two YY1 core binding sites at -40/-37 bp (YY1A) and, on the reverse strand, at -32/-29 bp (YY1B) immediately adjacent to the TATA box. In transfections using Col1a1-luciferase constructs, mutation of YY1A decreased activity completely (wild-type p350 (p350wt), -222/+113 bp) or partially (p130wt, -84 bp/+13 bp), whereas mutation of YY1B blocked the expression of both promoter constructs. Cotransfection with pCMV-YY1 increased p350wt and p130wt activities by as much as 10-fold, whereas antisense YY1 decreased constitutive expression and blocked the increased activity due to pCMV-YY1 overexpression. The mTgTA constructs were devoid of activity, arguing for a requirement for cognate binding of the TATA box-binding protein (TBP). Electrophoretic mobility shift assays performed under conditions permitting TBP binding showed that recombinant TBP/TFIID and YY1 could bind to the -56/-9 bp fragment and that YY1B was the preferred site for YY1 binding. Our results indicate that YY1 binds to the Col1a1 proximal promoter and functions as a positive regulator of constitutive activity in fibroblasts. Although YY1 is not sufficient for transcriptional initiation, it is a required component of the transcription machinery in this promoter.


Assuntos
Colágeno Tipo I , Colágeno/genética , Colágeno/metabolismo , Proteínas de Ligação a DNA/metabolismo , Regulação da Expressão Gênica , Fatores de Transcrição/metabolismo , Transcrição Gênica , Células 3T3 , Animais , Sequência de Bases , Sítios de Ligação , Núcleo Celular/metabolismo , Cadeia alfa 1 do Colágeno Tipo I , Análise Mutacional de DNA , Fatores de Ligação de DNA Eritroide Específicos , Luciferases/metabolismo , Camundongos , Dados de Sequência Molecular , Mutação , Oligonucleotídeos Antissenso/farmacologia , Regiões Promotoras Genéticas , Ligação Proteica , Fator de Transcrição TFIID , Fatores de Transcrição TFII/metabolismo , Transfecção , Fator de Transcrição YY1
12.
Am J Nephrol ; 21(6): 502-6, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11799270

RESUMO

Alcaligenes xylosoxidans is an uncommon cause of peritonitis in patients on maintenance continuous ambulatory peritoneal dialysis (CAPD). Peritonitis caused by A. xylosoxidans usually carries a poor prognosis because of the pathogen's virulence and its universal resistance to most antimicrobial agents. Even after early Tenckhoff catheter removal, the transport property of the peritoneum is often irreversibly damaged, leading to permanent technique failure. We report 2 patients with CAPD-associated peritonitis due to A. xylosoxidans sp. xylosoxidans who were successfully cured with a combination of piperacillin and tazobactam. One of them subsequently returned uneventfully to CAPD.


Assuntos
Alcaligenes , Infecções por Bactérias Gram-Negativas/etiologia , Ácido Penicilânico/análogos & derivados , Diálise Peritoneal Ambulatorial Contínua/efeitos adversos , Peritonite/microbiologia , Adulto , Inibidores Enzimáticos/uso terapêutico , Feminino , Infecções por Bactérias Gram-Negativas/tratamento farmacológico , Humanos , Pessoa de Meia-Idade , Ácido Penicilânico/uso terapêutico , Penicilinas/uso terapêutico , Peritonite/tratamento farmacológico , Piperacilina/uso terapêutico , Tazobactam
15.
Arthritis Rheum ; 43(10): 2189-201, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11037878

RESUMO

OBJECTIVE: To develop a reproducible immortalized human chondrocyte culture model for studying the regulation of chondrocyte functions relevant to arthritic diseases in adult humans. METHODS: Primary adult articular chondrocytes were immortalized with a retrovirus expressing a temperature-sensitive mutant of SV40-large T antigen (tsTAg). The established tsT/AC62 chondrocyte cell line was examined in monolayer and alginate culture systems. The levels of messenger RNA (mRNA) encoding cartilage matrix proteins and interleukin-1beta (IL-1beta)-inducible mRNA were analyzed by reverse transcriptase-polymerase chain reaction. Matrix protein synthesis was analyzed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis of 35S-sulfate-labeled proteoglycans and Western blotting of type II collagen and aggrecan. Type II collagen (COL2A1)-luciferase reporter gene expression was analyzed by transient transfection. Phosphorylated stress-activated protein kinase/c-Jun N-terminal kinase (SAPK/JNK), p38 mitogen-activated protein kinase (p38 MAPK), and activating transcription factor 2 (ATF-2) were detected by Western blotting. RESULTS: The tsT/AC62 cells expressed TAg at the permissive temperature (32degrees C), and the loss of TAg at 37 degrees C and 39 degrees C correlated with decreased cell proliferation. Cells in alginate culture deposited abundant alcian blue-stainable matrix and continued to proliferate at 32 degrees C. Preferential retention of aggrecan was observed in the cell-associated matrix, while biglycan and decorin were secreted into the medium of monolayer and alginate cultures. The levels of COL2A1 and aggrecan mRNA were increased after transfer from monolayer to alginate culture at 32 degrees C. Treatment with IL-1beta decreased COL2A1 and aggrecan mRNA levels and increased the levels of matrix metalloproteinases 1, 3, and 13 mRNA, as well as those of cyclooxygenase 2, type I collagen, and secretory phospholipase A2 type IIA mRNA, but not those of inducible nitric oxide synthase mRNA. IL-1beta also stimulated phosphorylation of p38 MAPK, SAPK/JNK, and ATF-2. The p38 MAPK-selective inhibitor, SB203580, partially reversed IL-1beta-induced inhibition of COL2A1 mRNA levels and COL2A1-luciferase reporter gene expression. CONCLUSION: The tsT/AC62 cells provide a reproducible model that mimics the adult articular chondrocyte phenotype, particularly in alginate culture, and demonstrates characteristic responses to IL-1beta. These studies also show, for the first time, that p38 MAPK is one of the signals required for IL-1beta-induced inhibition of COL2A1 gene expression. Availability of this model will permit identification of signals that regulate cytokine responses, and will also provide rational strategies for targeting these pathways.


Assuntos
Condrócitos/metabolismo , Adulto , Azul Alciano , Alginatos/farmacologia , Antígenos Transformantes de Poliomavirus/biossíntese , Células Cultivadas , Corantes , Proteínas da Matriz Extracelular/genética , Humanos , Interleucina-1/genética , Masculino , Metaloproteinase 1 da Matriz/análise , Metaloproteinase 3 da Matriz/análise , Pessoa de Meia-Idade , Fenótipo , Proteoglicanas/biossíntese , RNA Mensageiro/metabolismo
17.
Mol Cell Biol ; 19(10): 6803-14, 1999 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-10490619

RESUMO

Potent induction of the gene coding for human prointerleukin 1beta (il1b) normally requires a far-upstream inducible enhancer in addition to a minimal promoter located between positions -131 and +12. The transcription factor Spi-1 (also called PU.1) is necessary for expression and binds to the minimal promoter, thus providing an essential transcription activation domain (TAD). In contrast, infection by human cytomegalovirus (HCMV) can strongly activate il1b via the expression of immediate early (IE) viral proteins and eliminates the requirement for the upstream enhancer. Spi-1 has been circumstantially implicated as a host factor in this process. We report here the molecular basis for the direct involvement of Spi-1 in HCMV activation of il1b. Transfection of Spi-1-deficient HeLa cells demonstrated both the requirement of Spi-1 for IE activity and the need for a shorter promoter (-59 to +12) than that required in the absence of IE proteins. Furthermore, in contrast to normal, enhancer-dependent il1b expression, which absolutely requires both the Spi-1 winged helix-turn-helix (wHTH) DNA-binding domain and the majority of the Spi-1 TAD, il1b expression in the presence of IE proteins does not require the Spi-1 TAD, which plays a synergistic role. In addition, we demonstrate that a single IE protein, IE2, is critical for the induction of il1b. Protein-protein interaction experiments revealed that the wing motif within the Spi-1 wHTH domain directly recruits IE2. In turn, IE2 physically associates with the Spi-1 wing and requires the integrity of at least one region of IE2. Functional analysis demonstrates that both this region and a carboxy-terminal acidic TAD are required for IE2 function. Therefore, we propose a protein-tethered transactivation mechanism in which the il1b promoter-bound Spi-1 wHTH tethers IE2, which provides a TAD, resulting in the transactivation of il1b.


Assuntos
Proteínas Imediatamente Precoces/metabolismo , Interleucina-1/genética , Glicoproteínas de Membrana , Proteínas Proto-Oncogênicas/metabolismo , Transativadores/metabolismo , Ativação Transcricional , Proteínas do Envelope Viral , Proteínas Virais , Sítios de Ligação , Proteínas de Ligação a DNA/metabolismo , Elementos Facilitadores Genéticos , Células HeLa , Sequências Hélice-Alça-Hélice , Humanos , Proteínas Imediatamente Precoces/genética , Modelos Genéticos , Regiões Promotoras Genéticas , Ligação Proteica , Estrutura Secundária de Proteína , Proteínas Proto-Oncogênicas/deficiência , Proteínas Proto-Oncogênicas/genética , Transativadores/deficiência , Transativadores/genética
18.
Genes Dev ; 13(2): 202-12, 1999 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-9925644

RESUMO

In the early Caenorhabditis elegans embryo, maternally expressed PIE-1 protein is required in germ-line blastomeres to inhibit somatic differentiation, maintain an absence of mRNA transcription, and block phosphorylation of the RNA polymerase II large subunit (Pol II) carboxy-terminal domain (CTD). We have determined that PIE-1 can function as a transcriptional repressor in cell culture assays. By fusing PIE-1 sequences to the yeast GAL4 DNA-binding domain, we have identified a PIE-1 repression domain that appears to inhibit the transcriptional machinery directly. A sequence element that is required for this repressor activity is similar to the Pol II CTD heptapeptide repeat, suggesting that the PIE-1 repression domain might target a protein complex that can bind the CTD. An alteration of this sequence element that blocks repression also impairs the ability of a transgene to rescue a pie-1 mutation, suggesting that this repressor activity may be important for PIE-1 function in vivo.


Assuntos
Proteínas de Caenorhabditis elegans , Caenorhabditis elegans/genética , Proteínas Nucleares/metabolismo , RNA Polimerase II/antagonistas & inibidores , Proteínas Repressoras/metabolismo , Transcrição Gênica , Sequência de Aminoácidos , Animais , Animais Geneticamente Modificados , Caenorhabditis elegans/embriologia , Caenorhabditis elegans/metabolismo , Diferenciação Celular , Genes Reporter , Células Germinativas/metabolismo , Células HeLa , Proteínas de Helminto/química , Proteínas de Helminto/genética , Proteínas de Helminto/metabolismo , Humanos , Dados de Sequência Molecular , Mutação , Proteínas Nucleares/química , Proteínas Nucleares/genética , Fosforilação , RNA Polimerase II/química , RNA Polimerase II/metabolismo , Proteínas Recombinantes de Fusão/química , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Proteínas Repressoras/química , Proteínas Repressoras/genética , Alinhamento de Sequência
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