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1.
J Biol Chem ; 297(4): 101211, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34547292

RESUMO

Benzylisoquinoline alkaloids (BIAs) are a class of specialized metabolites with a diverse range of chemical structures and physiological effects. Codeine and morphine are two closely related BIAs with particularly useful analgesic properties. The aldo-keto reductase (AKR) codeinone reductase (COR) catalyzes the final and penultimate steps in the biosynthesis of codeine and morphine, respectively, in opium poppy (Papaver somniferum). However, the structural determinants that mediate substrate recognition and catalysis are not well defined. Here, we describe the crystal structure of apo-COR determined to a resolution of 2.4 Å by molecular replacement using chalcone reductase as a search model. Structural comparisons of COR to closely related plant AKRs and more distantly related homologues reveal a novel conformation in the ß1α1 loop adjacent to the BIA-binding pocket. The proximity of this loop to several highly conserved active-site residues and the expected location of the nicotinamide ring of the NADP(H) cofactor suggest a model for BIA recognition that implies roles for several key residues. Using site-directed mutagenesis, we show that substitutions at Met-28 and His-120 of COR lead to changes in AKR activity for the major and minor substrates codeinone and neopinone, respectively. Our findings provide a framework for understanding the molecular basis of substrate recognition in COR and the closely related 1,2-dehydroreticuline reductase responsible for the second half of a stereochemical inversion that initiates the morphine biosynthesis pathway.


Assuntos
Benzilisoquinolinas/química , Modelos Moleculares , Álcool Oxidorredutases Dependentes de NAD(+) e NADP(+)/química , Papaver/enzimologia , Proteínas de Plantas/química , Benzilisoquinolinas/metabolismo , Cristalografia por Raios X , Álcool Oxidorredutases Dependentes de NAD(+) e NADP(+)/metabolismo , Proteínas de Plantas/metabolismo , Domínios Proteicos , Relação Estrutura-Atividade
3.
J Food Prot ; 87(4): 100245, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38387832

RESUMO

Antimicrobial resistance (AMR) presents a significant threat to human health worldwide. One important source of antimicrobial-resistant infections in humans is exposure to animals or animal products. In a phased survey, we investigated AMR in 300 Escherichia coli isolates and 300 enterococci (Enterococcus faecalis and E. faecium) isolates each from the carcasses of poultry, pigs, very young calves, and dairy cattle (food animals); all Salmonella isolates from poultry, very young calves, and dairy cattle; and 300 Campylobacter (Campylobacter jejuni and C. coli) isolates from poultry. The highest resistance levels in E. coli were found for sulfamethoxazole, tetracycline, and streptomycin, for all food animals. Cefotaxime-resistant E. coli were not found and low resistance to ciprofloxacin, colistin, and gentamicin was observed. The majority of enterococci isolates from all food animals were bacitracin-resistant. Erythromycin- and/or tetracycline-resistant enterococci isolates were found in varying proportions from all food animals. Ampicillin- or vancomycin-resistant enterococci isolates were not identified, and ciprofloxacin-resistant E. faecalis were not found. Salmonella isolates were only recovered from very young calves and all eight isolates were susceptible to all tested antimicrobials. Most Campylobacter isolates were susceptible to all tested antimicrobials, although 16.6% of C. jejuni were resistant to quinolones and tetracycline. Results suggest that AMR in E. coli, enterococci, Salmonella, and Campylobacter isolates from food animals in New Zealand is low, and currently, AMR in food animals poses a limited public health risk. Despite the low prevalence of AMR in this survey, ongoing monitoring of antimicrobial susceptibility in bacteria from food animals is recommended, to ensure timely detection of AMR with potential impacts on animal and human health.


Assuntos
Antibacterianos , Campylobacter , Animais , Bovinos , Humanos , Suínos , Antibacterianos/farmacologia , Escherichia coli , Nova Zelândia , Farmacorresistência Bacteriana , Ciprofloxacina , Tetraciclina , Enterococcus , Aves Domésticas , Salmonella , Testes de Sensibilidade Microbiana
4.
Pediatr Neurol ; 155: 55-61, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38608551

RESUMO

BACKGROUND: To examine the association between race, ethnicity, and parental educational attainment on tic-related outcomes among Tourette Syndrome (TS) participants in the Tourette Association of America International Consortium for Genetics (TAAICG) database. METHODS: 723 participants in the TAAICG dataset aged ≤21 years were included. The relationships between tic-related outcomes and race and ethnicity were examined using linear and logistic regressions. Parametric and nonparametric tests were performed to examine the association between parental educational attainment and tic-related outcomes. RESULTS: Race and ethnicity were collapsed as non-Hispanic white (N=566, 88.0%) versus Other (N=77, 12.0%). Tic symptom onset was earlier by 1.1 years (P < 0.0001) and TS diagnosis age was earlier by 0.9 years (P = 0.0045) in the Other group (versus non-Hispanic white). Sex and parental education as covariates did not contribute to the differences observed in TS diagnosis age. There were no significant group differences observed across the tic-related outcomes in parental education variable. CONCLUSIONS: Our study was limited by the low number of nonwhite or Hispanic individuals in the cohort. Racial and ethnic minoritized groups experienced an earlier age of TS diagnosis than non-Hispanic white individuals. Tic severity did not differ between the two groups, and parental educational attainment did not affect tic-related outcomes. There remain significant disparities and gaps in knowledge regarding TS and associated comorbid conditions. Our study suggests the need for more proactive steps to engage individuals with tic disorders from all racial and ethnic minoritized groups to participate in research studies.


Assuntos
Determinantes Sociais da Saúde , Síndrome de Tourette , Humanos , Masculino , Feminino , Adolescente , Criança , Adulto Jovem , Pré-Escolar , Escolaridade , Adulto , Pais , Estados Unidos , Etnicidade
5.
Brain Commun ; 5(3): fcad106, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37265597

RESUMO

X-linked dystonia parkinsonism is a neurodegenerative movement disorder that affects men whose mothers originate from the island of Panay, Philippines. Current evidence indicates that the most likely cause is an expansion in the TAF1 gene that may be amenable to treatment. To prepare for clinical trials of therapeutic candidates for X-linked dystonia parkinsonism, we focused on the identification of quantitative phenotypic measures that are most strongly associated with disease progression. Our main objective is to establish a comprehensive, quantitative assessment of movement dysfunction and bulbar motor impairments that are sensitive and specific to disease progression in persons with X-linked dystonia parkinsonism. These measures will set the stage for future treatment trials. We enrolled patients with X-linked dystonia parkinsonism and performed a comprehensive oromotor, speech and neurological assessment. Measurements included patient-reported questionnaires regarding daily living activities and both neurologist-rated movement scales and objective quantitative measures of bulbar function and nutritional status. Patients were followed for 18 months from the date of enrollment and evaluated every 6 months during that period. We analysed a total of 87 men: 29 were gene-positive and had symptoms at enrollment, seven were gene-positive and had no symptoms at enrollment and 51 were gene-negative. We identified measures that displayed a significant change over the study. We used principal variables analysis to identify a minimal battery of 21 measures that explains 67.3% of the variance over the course of the study. These measures included patient-reported, clinician-rated and objective quantitative outcomes that may serve as endpoints in future clinical trials.

6.
Infect Prev Pract ; 4(1): 100197, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35005602

RESUMO

BACKGROUND: Antimicrobial resistance is increasingly prevalent worldwide. The inappropriate use of antimicrobials, including in the hospital setting, is considered a major driver of antimicrobial resistance. AIM: To inform improvements in antimicrobial stewardship, we undertook point prevalence surveys of antimicrobial prescribing at Yangon Children's Hospital and Yangon General Hospital in Yangon, Myanmar. METHODS: We conducted our surveys using the Global Point-Prevalence Survey of Antimicrobial Consumption and Resistance (Global-PPS) method. All inpatients who were prescribed an antimicrobial on the day of the survey were included in the analysis. FINDINGS: We evaluated a total of 1,980 patients admitted to two hospitals during December 2019. Of these, 1,255 (63.4%) patients were prescribed a total of 2,108 antimicrobials. Among antimicrobials prescribed, 722 (34.3%) were third-generation cephalosporins, the most commonly prescribed antimicrobial class. A total of 940 (44.6%) antimicrobials were prescribed for community-acquired infection, and 724 (34.3%) for surgical prophylaxis. Of 2,108 antimicrobials, 317 (15.0%) were prescribed for gastrointestinal tract prophylaxis, 305 (14.5%) for skin, soft tissue, bone and joint prophylaxis, and 303 (14.4%) for pneumonia treatment. A stop or review date was documented for 350 (16.6%) antimicrobial prescriptions, 673 (31.9%) antimicrobial prescriptions were guideline compliant, and 1,335 (63.3%) antimicrobials were administered via the parenteral route. Of 1,083 antimicrobials prescribed for a therapeutic use, 221 (20.4%) were targeted therapy. CONCLUSION: Our findings underscore the need to update and expand evidence-based guidelines for antimicrobial use, promote the benefits of targeted antimicrobial therapy, and support the implementation of hospital-based antimicrobial stewardship programmes at the hospitals surveyed.

7.
Nat Commun ; 13(1): 6768, 2022 11 09.
Artigo em Inglês | MEDLINE | ID: mdl-36351903

RESUMO

Opium poppy accumulates copious amounts of several benzylisoquinoline alkaloids including morphine, noscapine, and papaverine, in the specialized cytoplasm of laticifers, which compose an internal secretory system associated with phloem throughout the plant. The contiguous latex includes an abundance of related proteins belonging to the pathogenesis-related (PR)10 family known collectively as major latex proteins (MLPs) and representing at least 35% of the total cellular protein content. Two latex MLP/PR10 proteins, thebaine synthase and neopione isomerase, have recently been shown to catalyze late steps in morphine biosynthesis previously assigned as spontaneous reactions. Using a combination of sucrose density-gradient fractionation-coupled proteomics, differential scanning fluorimetry, isothermal titration calorimetry, and X-ray crystallography, we show that the major latex proteins are a family of alkaloid-binding proteins that display altered conformation in the presence of certain ligands. Addition of MLP/PR10 proteins to yeast strains engineered with morphine biosynthetic genes from the plant significantly enhanced the conversion of salutaridine to morphinan alkaloids.


Assuntos
Alcaloides , Benzilisoquinolinas , Papaver , Papaver/genética , Papaver/metabolismo , Látex/química , Alcaloides/química , Benzilisoquinolinas/metabolismo , Morfina , Saccharomyces cerevisiae/metabolismo
8.
Artigo em Inglês | MEDLINE | ID: mdl-34000162

RESUMO

The Psychiatric Consultation Service at Massachusetts General Hospital sees medical and surgical inpatients with comorbid psychiatric symptoms and conditions. During their twice-weekly rounds, Dr Stern and other members of the Consultation Service discuss diagnosis and management of hospitalized patients with complex medical or surgical problems who also demonstrate psychiatric symptoms or conditions. These discussions have given rise to rounds reports that will prove useful for clinicians practicing at the interface of medicine and psychiatry.


Assuntos
Transtornos Mentais , Psiquiatria , Criança , Diagnóstico Diferencial , Hospitais Gerais , Humanos , Hipercinese/diagnóstico , Hipercinese/terapia , Transtornos Mentais/diagnóstico , Transtornos Mentais/terapia , Encaminhamento e Consulta
9.
Am J Trop Med Hyg ; 103(6): 2518-2527, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32996447

RESUMO

Understanding patterns and trends of antimicrobial resistance (AMR) in Salmonella Typhi can guide empiric treatment recommendations and contribute to country decisions about typhoid conjugate vaccine (TCV) introduction. We systematically reviewed PubMed and Web of Science for articles reporting the proportion of Salmonella Typhi isolates resistant to individual antimicrobials worldwide from any time period. Isolates resistant to chloramphenicol, ampicillin, and trimethoprim-sulfamethoxazole were classified as multidrug resistant (MDR), and isolates that were MDR plus resistant to a fluoroquinolone and a third-generation cephalosporin were extensively drug resistant (XDR). Among the 198 articles eligible for analysis, a total of 55,459 Salmonella Typhi isolates were tested for AMR (median 80; range 2-5,191 per study). Of isolates from 2015 through 2018 in Asia, 1,638 (32.6%) of 5,032 were MDR, 167 (5.7%) of 2,914 were resistant to third-generation cephalosporins, and 148 (8.3%) of 1,777 were resistant to azithromycin. Two studies from Pakistan reported 14 (2.6%) of 546 isolates were XDR. In Africa, the median proportion of Salmonella Typhi isolates that were MDR increased each consecutive decade from 1990 to 1999 through 2010 to 2018. Salmonella Typhi has developed resistance to an increasing number of antimicrobial classes in Asia, where XDR Salmonella Typhi is now a major threat, whereas MDR has expanded in Africa. We suggest continued and increased surveillance is warranted to inform empiric treatment decisions and that AMR data be incorporated into country decisions on TCV introduction.


Assuntos
Antibacterianos/farmacologia , Farmacorresistência Bacteriana , Saúde Global , Infecções por Salmonella/microbiologia , Salmonella typhi/efeitos dos fármacos , Humanos
10.
Front Neurol ; 11: 591418, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33329340

RESUMO

Background: Cervical dystonia (CD) is a rare disorder, and health care providers might be unfamiliar with its presentation, thus leading to delay in the initial diagnosis. The lack of awareness displays the need to highlight the clinical features and treatment in cervical dystonia. In our cohort, we have identified an earlier age of onset in men, despite an overall preponderance of affected women. Objective: We aim to identify the prevalence, age of onset, spread, and treatment modalities of CD in the population. We also highlight the barriers which patients encounter related to diagnosis, follow-up, and treatment. Methods: We reviewed 149 CD patients who attended specialized Dystonia Clinics over a 14-year period. Dystonia severity was rated using the Burke-Fahn-Marsden (BFM), Tsui, and Toronto Western Spasmodic Torticollis Rating Scales (TWSTRS). Mood and quality of life were assessed using Beck Depression Inventory (BDI), Beck Anxiety Inventory (BAI), and 36-Item Short Form Health Survey (SF-36). Results: CD patients were majority White (91.3%) and more commonly female (75.8%). Men had an earlier median age of onset, 40.5 years (p = 0.044). BAI revealed a mean score of 7.2 (±6.4, n = 50) indicating minimal anxiety while BDI revealed a mean score of 7.30 (±7.6, n = 50) indicating minimal depression. The only SF-36 subscales associated with CD severity were physical functioning (p = 0.040) pain (p = 0.008) and general health (p = 0.014). Conclusion: There appear to be gender differences in both the prevalence and age of onset of the disease. There was a 3-fold higher incidence in women than in men. CD patients of both sexes experience barriers to care, which can be reflected in their quality of life and time-to-diagnosis. In addition, males were less likely to experience an objective benefit with botulinum toxin treatment and more likely to discontinue care. Greater awareness of CD by health care providers is important to reduce the time-to-diagnosis.

11.
Cancer Epidemiol Biomarkers Prev ; 20(3): 530-6, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21217086

RESUMO

BACKGROUND: There is some evidence from experimental studies that long-chain n-3 and n-6 fatty acids may be able to modify early skin carcinogenesis, but whether this applies in the general population is not known. METHODS: We investigated associations between serum polyunsaturated fatty acid concentrations and p53 expression in normal skin, as a biomarker of early UV-induced carcinogenesis, in an unselected sample of Australian adults. Participants in the Nambour Skin Cancer Prevention Trial provided a dorsal hand punch biopsy which was used for immunohistochemical assessment of p53 immunoreactivity. Cross-sectional associations with serum fatty acid concentrations were analyzed in 139 participants, adjusting for confounding variables including skin phenotype, past sun exposure, and smoking status. RESULTS: There was an inverse association, showing a dose-response relationship, between total n-3 fatty acid serum concentrations and p53 immunoreactivity in the whole epidermis and the basal layer. This was particularly due to eicosapentanoic acid and docosahexanoic acid concentrations. There was no evidence for increased p53 immunoreactivity in participants with relatively high serum n-6 fatty acid concentrations. The ratio of n-3 to n-6 fatty acid concentrations was not associated with p53 immunoreactivity. CONCLUSION: These results add to growing evidence that long-chain fatty acids may be able to modify early skin carcinogenesis. IMPACT: The prospect that increased intake of n-3 fatty acids could help prevent skin cancer is attractive.


Assuntos
Ácidos Graxos Ômega-3/sangue , Ácidos Graxos Ômega-6/sangue , Neoplasias Cutâneas/metabolismo , Pele/metabolismo , Proteína Supressora de Tumor p53/biossíntese , Adulto , Idoso , Austrália , Transformação Celular Neoplásica/metabolismo , Transformação Celular Neoplásica/efeitos da radiação , Estudos Transversais , Ácidos Docosa-Hexaenoicos/sangue , Ácido Eicosapentaenoico/sangue , Feminino , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Pele/efeitos da radiação , Neoplasias Cutâneas/sangue , Neoplasias Cutâneas/etiologia , Raios Ultravioleta
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