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1.
Cell Host Microbe ; 31(8): 1359-1370.e7, 2023 08 09.
Artigo em Inglês | MEDLINE | ID: mdl-37453420

RESUMO

Glutathione (GSH) is an abundant metabolite within eukaryotic cells that can act as a signal, a nutrient source, or serve in a redox capacity for intracellular bacterial pathogens. For Francisella, GSH is thought to be a critical in vivo source of cysteine; however, the cellular pathways permitting GSH utilization by Francisella differ between strains and have remained poorly understood. Using genetic screening, we discovered a unique pathway for GSH utilization in Francisella. Whereas prior work suggested GSH catabolism initiates in the periplasm, the pathway we define consists of a major facilitator superfamily (MFS) member that transports intact GSH and a previously unrecognized bacterial cytoplasmic enzyme that catalyzes the first step of GSH degradation. Interestingly, we find that the transporter gene for this pathway is pseudogenized in pathogenic Francisella, explaining phenotypic discrepancies in GSH utilization among Francisella spp. and revealing a critical role for GSH in the environmental niche of these bacteria.


Assuntos
Francisella tularensis , Francisella , Glutationa/metabolismo , Francisella/genética , Francisella/metabolismo , Francisella tularensis/genética , Francisella tularensis/crescimento & desenvolvimento , Francisella tularensis/metabolismo , Elementos de DNA Transponíveis , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Filogenia , Macrófagos/parasitologia , Animais , Camundongos , Tularemia/microbiologia
2.
bioRxiv ; 2023 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-37205512

RESUMO

The study of bacteria has yielded fundamental insights into cellular biology and physiology, biotechnological advances and many therapeutics. Yet due to a lack of suitable tools, the significant portion of bacterial diversity held within the candidate phyla radiation (CPR) remains inaccessible to such pursuits. Here we show that CPR bacteria belonging to the phylum Saccharibacteria exhibit natural competence. We exploit this property to develop methods for their genetic manipulation, including the insertion of heterologous sequences and the construction of targeted gene deletions. Imaging of fluorescent protein-labeled Saccharibacteria provides high spatiotemporal resolution of phenomena accompanying epibiotic growth and a transposon insertion sequencing genome-wide screen reveals the contribution of enigmatic Saccharibacterial genes to growth on their Actinobacteria hosts. Finally, we leverage metagenomic data to provide cutting-edge protein structure-based bioinformatic resources that support the strain Southlakia epibionticum and its corresponding host, Actinomyces israelii , as a model system for unlocking the molecular underpinnings of the epibiotic lifestyle.

3.
Clin Oncol (R Coll Radiol) ; 35(2): e215-e226, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36494250

RESUMO

AIMS: Our understanding of the impact of adjuvant therapy on longitudinal quality of life (QoL) following surgery for patients with uterine cancer is limited. The purpose of this study was to compare QoL in patients who have undergone surgery with or without radiation therapy for uterine cancer. MATERIALS AND METHODS: This was a cross-sectional cohort study that examined women treated for uterine cancer at MD Anderson Cancer Center from 2006 to 2017. Participants included those who underwent hysterectomy/bilateral salphingo-oophorectomy alone, with brachytherapy or external beam radiation therapy (EBRT). A non-cancer cohort of women who underwent a hysterectomy/bilateral salphingo-oophorectomy for benign indications was also identified (non-CA). To compare QoL we used the Functional Assessment of Cancer Therapy - Endometrial survey (FACT-En), a validated survey used to assess QoL. The survey has five subscales: physical, social, emotional, functional and an endometrial cancer-specific subscale. Cohorts were compared using ANOVA tests. RESULTS: In total, 309 women responded to the questionnaire (hysterectomy/bilateral salphingo-oophorectomy 64, brachytherapy 77, EBRT 96, non-CA 72). The median time from surgery to survey completion was 6.7 years. The mean total FACT-En score for the entire cohort was 144 [standard deviation 22]. Overall QoL was different between cohorts, with the EBRT cohort reporting the lowest QoL (mean 139.4 [21.6]) and the brachytherapy cohort the highest (150.6 [18.2], P = 0.006). Among patients who had undergone cancer treatment, the EBRT cohort reported the worst endometrial-specific QoL (53.5 [8.6]), while again the brachytherapy group reported the highest score (57.5 [6.1], P = 0.007). CONCLUSIONS: QoL differences in women who have undergone different treatments for uterine cancer may persist years after treatment. In women with endometrial cancer who require adjuvant therapy, brachytherapy does not appear to have any long-term detriments on QoL.


Assuntos
Braquiterapia , Sobreviventes de Câncer , Neoplasias do Endométrio , Neoplasias Uterinas , Humanos , Feminino , Qualidade de Vida , Estudos Transversais , Radioterapia Adjuvante , Estadiamento de Neoplasias , Neoplasias Uterinas/radioterapia , Neoplasias Uterinas/patologia , Neoplasias do Endométrio/radioterapia , Neoplasias do Endométrio/cirurgia
4.
Rheumatol Ther ; 9(1): 285-293, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35032324

RESUMO

INTRODUCTION: C-reactive protein (CRP) is an important non-specific marker of both acute and chronic inflammation and can be elevated in patients with psoriatic arthritis (PsA). However, the use of CRP testing in the management of PsA can vary. This study investigated how CRP testing is implemented in real-world clinical practice for disease management of PsA. METHODS: A point-in-time survey of rheumatologists and dermatologists and their next six consulting patients with PsA was conducted in France, Germany, Italy, Spain, UK (EU5), and the USA between June and August 2018. Use of CRP testing was obtained by asking the physician to state (yes/no) whether CRP was used to aid PsA diagnosis and/or to monitor the patient's disease activity. The number of CRP tests conducted in the last 12 months for each patient enrolled was provided. RESULTS: Data were collected for 2270 patients (USA, n = 595; EU5, n = 1675). In the EU5, CRP testing was conducted to aid diagnosis in 78.7% of patients (vs. 43.4% in USA) and CRP was used to monitor disease activity in 72.0% (vs. 34.6% in USA). The majority (80.9%) of patients in the EU5 had at least one CRP test in the last 12 months compared to 42.9% in the USA. Patients treated by rheumatologists (vs. dermatologists) were at least 50% more likely to have CRP tested for monitoring purposes, this difference being most pronounced in the USA. In the EU5, CRP testing was conducted a mean ± standard deviation of 2.7 ± 1.7 times during the last 12 months, versus 2.0 ± 1.4 in the USA. CONCLUSIONS: CRP was more commonly used for the diagnosis and monitoring of PsA in Europe compared to the USA and was more commonly ordered by rheumatologists than dermatologists. In the absence of a better serum biomarker of inflammation, more data are needed to understand how CRP testing should be used in the diagnosis and management PsA.

5.
J Urol ; 207(5): 1105-1115, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-34968146

RESUMO

PURPOSE: We sought to automate R.E.N.A.L. (for radius, exophytic/endophytic, nearness of tumor to collecting system, anterior/posterior, location relative to polar line) nephrometry scoring of preoperative computerized tomography scans and create an artificial intelligence-generated score (AI-score). Subsequently, we aimed to evaluate its ability to predict meaningful oncologic and perioperative outcomes as compared to expert human-generated nephrometry scores (H-scores). MATERIALS AND METHODS: A total of 300 patients with preoperative computerized tomography were identified from a cohort of 544 consecutive patients undergoing surgical extirpation for suspected renal cancer at a single institution. A deep neural network approach was used to automatically segment kidneys and tumors, and geometric algorithms were developed to estimate components of R.E.N.A.L. nephrometry score. Tumors were independently scored by medical personnel blinded to AI-scores. AI- and H-score agreement was assessed using Lin's concordance correlation and their predictive abilities for both oncologic and perioperative outcomes were assessed using areas under the curve. RESULTS: Median age was 60 years (IQE 51-68), and 40% were female. Median tumor size was 4.2 cm and 91.3% had malignant tumors, including 27%, 37% and 24% with high stage, grade and necrosis, respectively. There was significant agreement between H-scores and AI-scores (Lin's ⍴=0.59). Both AI- and H-scores similarly predicted meaningful oncologic outcomes (p <0.001) including presence of malignancy, necrosis, and high-grade and -stage disease (p <0.003). They also predicted surgical approach (p <0.004) and specific perioperative outcomes (p <0.05). CONCLUSIONS: Fully automated AI-generated R.E.N.A.L. scores are comparable to human-generated R.E.N.A.L. scores and predict a wide variety of meaningful patient-centered outcomes. This unambiguous artificial intelligence-based scoring is intended to facilitate wider adoption of the R.E.N.A.L. score.


Assuntos
Inteligência Artificial , Neoplasias Renais , Computadores , Feminino , Humanos , Neoplasias Renais/diagnóstico por imagem , Neoplasias Renais/patologia , Neoplasias Renais/cirurgia , Pessoa de Meia-Idade , Necrose , Nefrectomia/métodos , Estudos Retrospectivos
6.
Clin Rheumatol ; 40(12): 4933-4942, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34287723

RESUMO

OBJECTIVES: To compare work absenteeism and short-term disability among adults with psoriasis or psoriatic arthritis (PsA), versus controls in the USA. METHODS: Adults eligible for work absenteeism and/or short-term disability benefits between 1/1/2009 and 4/30/2020 were screened in the IBM® MarketScan® Commercial and Health and Productivity Management Databases. The following groups were defined: (1) psoriasis: ≥ 2 psoriasis diagnoses ≥ 30 days apart and no PsA diagnoses; (2) PsA: ≥ 2 PsA diagnoses ≥ 30 days apart; (3) control: absence of psoriasis and PsA diagnoses. Controls were matched to psoriasis and PsA patients based on age, gender, index year, and comorbidities. Non-recreational work absences and sick leaves were evaluated in absentee-eligible patients, and short-term disability was evaluated in short-term disability-eligible patients. Costs (in 2019 USD) associated with each type of work absence were evaluated. RESULTS: 4261 psoriasis and 616 PsA absentee-eligible and 25,213 psoriasis and 3480 PsA short-term disability-eligible patients were matched to controls. Average non-recreational work absence costs were $1681, $1657, and $1217 for the PsA, psoriasis, and control group, respectively. Compared with psoriasis patients and controls, more PsA patients had sick leaves after 1 year (56.2% versus 55.6% and 41.5%, p < 0.0001). Similarly, short-term disability was more frequent in PsA patients than psoriasis patients and controls at year one (8.8% versus 5.6% and 4.7%, p < 0.0001) and corresponding costs were higher ($605, $406, and $335 on average, p < 0.0001). CONCLUSION: Annual work absenteeism and short-term disability were consistently greater among patients with PsA and psoriasis than controls, highlighting the substantial economic burden of psoriatic disease. Key points • Patients with PsA had greater short-term disability compared with patients with psoriasis and patients with neither psoriasis nor PsA. • Patients with PsA and patients with psoriasis incurred greater non-recreational work absences and sick leaves than patients with neither psoriasis nor PsA.


Assuntos
Artrite Psoriásica , Psoríase , Absenteísmo , Adulto , Artrite Psoriásica/epidemiologia , Eficiência , Humanos , Psoríase/epidemiologia , Estudos Retrospectivos , Estados Unidos
7.
Clin Rheumatol ; 40(10): 4061-4070, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33934270

RESUMO

OBJECTIVES: To compare healthcare resource utilization and costs among patients with psoriasis, psoriatic arthritis (PsA), and a control group of patients without psoriasis and PsA in the USA. METHODS: The IBM® MarketScan® Commercial Database was used to identify three adult patient groups from 1/1/2009 through 4/30/2020: (1) Psoriasis: ≥ 2 diagnoses ≥ 30 days apart for psoriasis (no PsA diagnoses); (2) PsA: ≥ 2 diagnoses for PsA; (3) Control: no psoriasis or PsA diagnoses in their entire claims records. Patients with comorbid rheumatoid arthritis, ankylosing spondylitis, Crohn's disease, or ulcerative colitis were excluded from the analyses. Controls were matched 1:1 to psoriasis and PsA patients based on age, gender, index year, and number of non-rheumatological comorbidities. Healthcare resource utilization and costs (in 2019 USD) were evaluated descriptively and through mixed models for five years of follow-up. RESULTS: A total of 142,531 psoriasis and 21,428 PsA patients were matched to the control group (N = 163,959). Annual all-cause healthcare costs per patient were $7,470, $11,062, and $29,742 for the control, psoriasis, and PsA groups, respectively. All-cause healthcare costs increased over time and were significantly greater among PsA vs. psoriasis (p < 0.0001) and the control groups (p < 0.0001). Across all categories of healthcare resources, utilization was greatest among patients with PsA and lowest in the control group. CONCLUSION: Annual healthcare costs and resource utilization were significantly higher with PsA compared with psoriasis and the control group, confirming the substantial economic burden of PsA. The cost disparity between these patient groups highlights a continued unmet medical need. Key Points • Patients with PsA incurred significantly greater healthcare resource utilization and costs than patients with psoriasis and patients without psoriasis and PsA. • Significantly greater costs and healthcare resource utilization were also observed among patients with psoriasis compared with patients without psoriasis and PsA.


Assuntos
Artrite Psoriásica , Psoríase , Adulto , Artrite Psoriásica/terapia , Custos de Cuidados de Saúde , Humanos , Aceitação pelo Paciente de Cuidados de Saúde , Psoríase/terapia , Estudos Retrospectivos , Estados Unidos
8.
Nature ; 588(7837): 344-349, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32814344

RESUMO

Leucine-rich repeat kinase 2 (LRRK2) is the most commonly mutated gene in familial Parkinson's disease1 and is also linked to its idiopathic form2. LRRK2 has been proposed to function in membrane trafficking3 and colocalizes with microtubules4. Despite the fundamental importance of LRRK2 for understanding and treating Parkinson's disease, structural information on the enzyme is limited. Here we report the structure of the catalytic half of LRRK2, and an atomic model of microtubule-associated LRRK2 built using a reported cryo-electron tomography in situ structure5. We propose that the conformation of the LRRK2 kinase domain regulates its interactions with microtubules, with a closed conformation favouring oligomerization on microtubules. We show that the catalytic half of LRRK2 is sufficient for filament formation and blocks the motility of the microtubule-based motors kinesin 1 and cytoplasmic dynein 1 in vitro. Kinase inhibitors that stabilize an open conformation relieve this interference and reduce the formation of LRRK2 filaments in cells, whereas inhibitors that stabilize a closed conformation do not. Our findings suggest that LRRK2 can act as a roadblock for microtubule-based motors and have implications for the design of therapeutic LRRK2 kinase inhibitors.


Assuntos
Microscopia Crioeletrônica , Serina-Treonina Proteína Quinase-2 com Repetições Ricas em Leucina/química , Serina-Treonina Proteína Quinase-2 com Repetições Ricas em Leucina/metabolismo , Microtúbulos/química , Microtúbulos/metabolismo , Doença de Parkinson/metabolismo , Benzamidas/farmacologia , Biocatálise/efeitos dos fármacos , Dimerização , Dineínas/antagonistas & inibidores , Dineínas/metabolismo , Humanos , Cinesinas/antagonistas & inibidores , Cinesinas/metabolismo , Serina-Treonina Proteína Quinase-2 com Repetições Ricas em Leucina/antagonistas & inibidores , Serina-Treonina Proteína Quinase-2 com Repetições Ricas em Leucina/ultraestrutura , Microtúbulos/ultraestrutura , Modelos Moleculares , Movimento/efeitos dos fármacos , Ligação Proteica , Domínios Proteicos/efeitos dos fármacos , Pirazóis/farmacologia , Repetições WD40
9.
PLoS Pathog ; 16(6): e1008566, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32492066

RESUMO

Host-derived glutathione (GSH) is an essential source of cysteine for the intracellular pathogen Francisella tularensis. In a comprehensive transposon insertion sequencing screen, we identified several F. tularensis genes that play central and previously unappreciated roles in the utilization of GSH during the growth of the bacterium in macrophages. We show that one of these, a gene we named dptA, encodes a proton-dependent oligopeptide transporter that enables growth of the organism on the dipeptide Cys-Gly, a key breakdown product of GSH generated by the enzyme γ-glutamyltranspeptidase (GGT). Although GGT was thought to be the principal enzyme involved in GSH breakdown in F. tularensis, our screen identified a second enzyme, referred to as ChaC, that is also involved in the utilization of exogenous GSH. However, unlike GGT and DptA, we show that the importance of ChaC in supporting intramacrophage growth extends beyond cysteine acquisition. Taken together, our findings provide a compendium of F. tularensis genes required for intracellular growth and identify new players in the metabolism of GSH that could be attractive targets for therapeutic intervention.


Assuntos
Proteínas de Bactérias , Francisella tularensis/fisiologia , Glutationa , Interações Hospedeiro-Patógeno/fisiologia , Macrófagos , Transglutaminases , Tularemia , Animais , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Linhagem Celular , Dipeptídeos/genética , Dipeptídeos/metabolismo , Feminino , Glutationa/genética , Glutationa/metabolismo , Macrófagos/metabolismo , Macrófagos/microbiologia , Macrófagos/patologia , Camundongos , Transglutaminases/genética , Transglutaminases/metabolismo , Tularemia/genética , Tularemia/metabolismo
10.
Clin Rheumatol ; 39(10): 2907-2917, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32367407

RESUMO

OBJECTIVE: To compare the relative efficacy of intravenous golimumab (GOL IV) and infliximab (IFX) for active ankylosing spondylitis (AS). METHODS: Propensity score (PS) methods were used to compare the efficacy of GOL IV 2 mg/kg and IFX 5 mg/kg using individual patient data (IPD) from the active arms of the phase 3 GO-ALIVE and ASSERT studies. Outcomes included the proportion of patients with a ≥ 20% improvement in the Assessment of Spondyloarthritis International Society Criteria (ASAS20), change from baseline in Bath Ankylosing Spondylitis Functional Index (BASFI) score, and change from baseline in C-reactive protein (CRP) levels from weeks 4-52. RESULTS: Before matching, 105 patients were treated with GOL IV and 201 patients were treated with IFX. After matching on all covariates, 118 patients were included in the ASAS20 analysis, 96 in the BASFI analysis, and 160 in the CRP analysis. After matching, GOL IV showed significantly greater improvement in ASAS20 response than IFX for weeks 28-44 (e.g., OR = 9.05 [95% CI 1.62-50.4] at week 44) and was comparable in change from baseline in BASFI scores and CRP levels to IFX at all time points. Results were robust for inclusion of different sets of covariates in scenario analyses. CONCLUSIONS: This is the first analysis of its kind to leverage clinical trial data to compare two biologics using PS methods in the treatment of active AS. Overall, GOL IV was associated with greater improvement in ASAS20 response than IFX in patients with AS at 28, 36, and 44 weeks of follow-up. Key Points • Although intravenous golimumab (GOL IV) and infliximab (IFX) are the only two IV-based tumor necrosis factor (TNF) inhibitors with demonstrated phase 3 clinical efficacy in patients with ankylosing spondylitis (AS), no study has evaluated their comparative efficacy in a head-to-head trial. • Propensity score matching was used to derive indirect treatment comparisons of GOL IV and IFX for ≥ 20% in the Assessment of Spondyloarthritis International Society Criteria (ASAS20), change in Bath Ankylosing Spondylitis Functional Index (BASFI), and change in C-reactive protein (CRP) using individual patient data from the GO-ALIVE and ASSERT phase 3 trials. • Propensity score matched indirect comparisons showed improved relative efficacy of GOL IV compared to IFX; after matching for up to 16 baseline covariates, GOL IV was associated with significantly greater odds of ASAS20 response at weeks 28, 36, and 44 than IFX as well as equivalent changes from baseline in BASFI and CRP. • This novel application of propensity score matching using data from phase 3 trials, the first analysis of its kind in AS, allowed adjustment for important imbalances in prognostic factors between trials to generate estimates of comparative efficacy between GOL IV and IFX in the absence of a head-to-head trial between these treatments.


Assuntos
Antirreumáticos , Espondilite Anquilosante , Anticorpos Monoclonais , Antirreumáticos/uso terapêutico , Humanos , Infliximab/uso terapêutico , Pontuação de Propensão , Espondilite Anquilosante/tratamento farmacológico , Resultado do Tratamento
11.
Clin Rheumatol ; 39(8): 2307-2315, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32107666

RESUMO

OBJECTIVE: To compare the relative efficacy of current and investigational biologic and oral small molecule (OSM) treatments for active ankylosing spondylitis (AS). METHODS: A systematic literature review was conducted to identify all phase 2/3 randomized trials of interest in patients with AS. Outcomes assessed were ≥ 20% improvement in the Assessment of Spondyloarthritis International Society Criteria (ASAS20) and change from baseline in Bath Ankylosing Spondylitis Functional Index (BASFI) and C-reactive protein (CRP) at weeks 12-16. Bayesian network meta-analyses were conducted for outcomes using a random effects model. Baseline-risk adjustment was also conducted to account for differences in placebo response across studies. Surface Under the Cumulative Ranking curve (SUCRA) values are reported, reflecting the relative probability that intervention was the best of all interventions. RESULTS: The investigational agent tofacitinib 5 mg was the top-ranked treatment (SUCRA, 93%) for ASAS20 response, followed by intravenous (IV) golimumab 2 mg/kg (90%). Golimumab IV 2 mg/kg and infliximab 5 mg/kg were the top two ranked treatments for change from baseline in BASFI (golimumab IV, 81%; infliximab, 80%) and change from baseline in CRP (infliximab, 90%; golimumab IV, 82%). CONCLUSIONS: Two approved therapies (golimumab IV, infliximab) and one investigational product ranked highest for efficacy in AS. Key Points • Although golimumab IV, infliximab, and tofacitinib ranked highest for efficacy in AS, differences in efficacy between approved and investigational therapies were not statistically significant.


Assuntos
Metanálise em Rede , Espondilite Anquilosante/tratamento farmacológico , Terapias em Estudo , Inibidores do Fator de Necrose Tumoral/administração & dosagem , Administração Intravenosa , Anticorpos Monoclonais , Teorema de Bayes , Humanos , Infliximab , Ensaios Clínicos Controlados Aleatórios como Assunto , Inibidores do Fator de Necrose Tumoral/uso terapêutico
12.
Internet Interv ; 18: 100289, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31890636

RESUMO

INTRODUCTION: Pharyngeal and laryngeal cancers are highly curable; however survivors are at high risk for long-term dysphagia after radiation. To address lack of access to preventive care in community settings, we developed a responsive web-based application to help patients adhere to preventive swallowing exercises and cope with radiation side effects. We conducted an interim study analysis to determine website usage characteristics and to examine the effect size for future trials. METHODS: Pharyngeal and laryngeal cancer patients were recruited for enrollment by speech language pathologists before primary radiation and introduced to the interactive website. The program (English and Spanish) features tracking logs for preventive exercises, instructional videos, patient stories and search features. Patients' self-reported swallowing function was assessed with the MD Anderson Dysphagia Inventory (MDADI) at baseline and at 6 months. Adherence to preventive exercises was assessed during the 10 week intervention. Number of unique website visits, total duration of website exposure, and rankings of the most popular webpages were calculated. Preliminary regression models were run using adherence and MDADI as outcomes. RESULTS: Of the 160 enrolled, 96 had 10-week adherence data and 61 had 6-month MDADI data. The average age was 63 (SD = 12.26), 49.4% were from rural counties, 44% had a high school education or lower, and 42% reported annual income of $30,000 or less. The average number of visits was 5.49 (SD = 9.96) and the average total time spent with the website was 41.09 min (SD =88.48). Preliminary analyses indicated that number of unique visits to the website was independently associated with increased adherence to preventive exercises (p = .001-.008). CONCLUSION: Our website showed significant effects in promoting adherence to swallowing exercises. However, our return visit rate showed that the platform needs improvement in navigability and usability for this older population undergoing challenging treatment in community settings with low resources.

13.
Cell ; 175(5): 1380-1392.e14, 2018 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-30343895

RESUMO

ADP-ribosylation of proteins can profoundly impact their function and serves as an effective mechanism by which bacterial toxins impair eukaryotic cell processes. Here, we report the discovery that bacteria also employ ADP-ribosylating toxins against each other during interspecies competition. We demonstrate that one such toxin from Serratia proteamaculans interrupts the division of competing cells by modifying the essential bacterial tubulin-like protein, FtsZ, adjacent to its protomer interface, blocking its capacity to polymerize. The structure of the toxin in complex with its immunity determinant revealed two distinct modes of inhibition: active site occlusion and enzymatic removal of ADP-ribose modifications. We show that each is sufficient to support toxin immunity; however, the latter additionally provides unprecedented broad protection against non-cognate ADP-ribosylating effectors. Our findings reveal how an interbacterial arms race has produced a unique solution for safeguarding the integrity of bacterial cell division machinery against inactivating post-translational modifications.


Assuntos
ADP Ribose Transferases/metabolismo , Proteínas de Bactérias/metabolismo , Toxinas Bacterianas/metabolismo , Proteínas do Citoesqueleto/metabolismo , N-Glicosil Hidrolases/metabolismo , ADP Ribose Transferases/química , ADP Ribose Transferases/genética , ADP-Ribosilação , Difosfato de Adenosina/metabolismo , Sequência de Aminoácidos , Proteínas de Bactérias/antagonistas & inibidores , Toxinas Bacterianas/química , Toxinas Bacterianas/genética , Domínio Catalítico , Proteínas do Citoesqueleto/antagonistas & inibidores , Escherichia coli/crescimento & desenvolvimento , Escherichia coli/imunologia , Escherichia coli/metabolismo , Humanos , Mutagênese Sítio-Dirigida , N-Glicosil Hidrolases/química , N-Glicosil Hidrolases/genética , Estrutura Terciária de Proteína , Subunidades Proteicas/genética , Subunidades Proteicas/metabolismo , Alinhamento de Sequência , Serratia/metabolismo , Imagem com Lapso de Tempo
14.
Cell Host Microbe ; 24(2): 285-295.e8, 2018 08 08.
Artigo em Inglês | MEDLINE | ID: mdl-30057173

RESUMO

Many pathogenic intracellular bacteria manipulate the host phago-endosomal system to establish and maintain a permissive niche. The fate and identity of these intracellular compartments is controlled by phosphoinositide lipids. By mechanisms that have remained undefined, a Francisella pathogenicity island-encoded secretion system allows phagosomal escape and replication of bacteria within host cell cytoplasm. Here we report the discovery that a substrate of this system, outside pathogenicity island A (OpiA), represents a family of wortmannin-resistant bacterial phosphatidylinositol (PI) 3-kinase enzymes with members found in a wide range of intracellular pathogens, including Rickettsia and Legionella spp. We show that OpiA acts on the Francisella-containing phagosome and promotes bacterial escape into the cytoplasm. Furthermore, we demonstrate that the phenotypic consequences of OpiA inactivation are mitigated by endosomal maturation arrest. Our findings suggest that Francisella, and likely other intracellular bacteria, override the finely tuned dynamics of phagosomal PI(3)P in order to promote intracellular survival and pathogenesis.


Assuntos
Francisella/crescimento & desenvolvimento , Francisella/patogenicidade , Interações Hospedeiro-Patógeno/fisiologia , Fagossomos/metabolismo , Fagossomos/microbiologia , Fosfatidilinositol 3-Quinase/metabolismo , Animais , Proteínas de Bactérias/metabolismo , Citoplasma/microbiologia , Replicação do DNA , Modelos Animais de Doenças , Endossomos/microbiologia , Feminino , Francisella/genética , Genes Bacterianos/genética , Ilhas Genômicas , Células HEK293 , Células HeLa , Humanos , Metabolismo dos Lipídeos , Macrófagos/microbiologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Fosfatidilinositóis/metabolismo , Células RAW 264.7 , Sistemas de Secreção Tipo VI/metabolismo , Fatores de Virulência/metabolismo
15.
Phys Med Biol ; 63(3): 035019, 2018 01 30.
Artigo em Inglês | MEDLINE | ID: mdl-29380750

RESUMO

We tested the ability of a single Compton camera (CC) to produce 3-dimensional (3D) images of prompt gammas (PGs) emitted during the irradiation of a tissue-equivalent plastic phantom with proton pencil beams for clinical doses delivered at clinical dose rates. PG measurements were made with a small prototype CC placed at three different locations along the proton beam path. We evaluated the ability of the CC to produce images at each location for two clinical scenarios: (1) the delivery of a single 2 Gy pencil beam from a hypo-fractionated treatment (~9 × 108 protons), and (2) a single pencil beam from a standard treatment (~1 × 108 protons). Additionally, the data measured at each location were combined to simulate measurements with a larger scale, clinical CC and its ability to image shifts in the Bragg peak (BP) range for both clinical scenarios. With our prototype CC, the location of the distal end of the BP could be seen with the CC placed up to 4 cm proximal or distal to the BP distal falloff. Using the data from the simulated full scale clinical CC, 3D images of the PG emission were produced with the delivery of as few as 1 × 108 protons, and shifts in the proton beam range as small as 2 mm could be detected for delivery of a 2 Gy spot. From these results we conclude that 3D PG imaging for proton range verification under clinical beam delivery conditions is possible with a single CC.


Assuntos
Raios gama , Processamento de Imagem Assistida por Computador/métodos , Imagens de Fantasmas , Terapia com Prótons/instrumentação , Terapia com Prótons/métodos , Humanos , Imageamento Tridimensional/métodos , Método de Monte Carlo
16.
IEEE Trans Radiat Plasma Med Sci ; 1(4): 358-367, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28736766

RESUMO

A Compton imaging method for medical applications that includes new energy determination and data filtering techniques has been tested using several point sources with known emission lines. Using a prototype Compton camera, a distance-of-closest approach technique has been employed to determine the initial energy of the incoming γs and to ensure the reconstructed source position is within an acceptable distance from the known γ source location. Further analysis is done by implementing a Compton line filtering technique, keeping only those interactions whose deposited energy in the first interaction matches the theoretical energy deposition predicted by the Compton equation. Using this new event filtering method, we see improvements in the full width at half maximum in the lateral profiles of γ point sources of up to 70% over standard Compton imaging methods, as well as achievable spatial resolutions in the reconstructed images of better than 2 mm. In addition, this new Compton imaging method was able to reconstruct an extended source of γ rays emitted during irradiation of a water tank with a clinical proton radiotherapy beam.

17.
Cell Host Microbe ; 20(5): 573-583, 2016 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-27832588

RESUMO

The intracellular bacterial pathogen Francisella tularensis causes tularemia, a zoonosis that can be fatal. The type VI secretion system (T6SS) encoded by the Francisella pathogenicity island (FPI) is critical for the virulence of this organism. Existing studies suggest that the complete repertoire of T6SS effectors delivered to host cells is encoded by the FPI. Using a proteome-wide approach, we discovered that the FPI-encoded T6SS exports at least three effectors encoded outside of the island. These proteins share features with virulence determinants of other pathogens, and we provide evidence that they can contribute to intramacrophage growth. The remaining proteins that we identified are encoded within the FPI. Two of these FPI-encoded proteins constitute effectors, whereas the others form a unique complex required for core function of the T6SS apparatus. The discovery of secreted effectors mediating interactions between Francisella and its host significantly advances our understanding of the pathogenesis of this organism.


Assuntos
Proteínas de Bactérias/metabolismo , Francisella tularensis/crescimento & desenvolvimento , Francisella tularensis/genética , Ilhas Genômicas , Interações Hospedeiro-Patógeno , Macrófagos/microbiologia , Fatores de Virulência/metabolismo , Proteínas de Bactérias/genética , Transporte Proteico , Sistemas de Secreção Tipo VI , Virulência , Fatores de Virulência/genética
18.
Clin Genet ; 89(3): 392-8, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26272410

RESUMO

Cancer screening recommendations for patients with Lynch-like syndrome (LLS) are not well defined. We evaluated adherence to Lynch syndrome (LS) screening recommendations, cancer risk perceptions, and communication within the families among colorectal cancer (CRC) survivors with LLS. Thirty-four participants with LLS completed a questionnaire about risk perception, adherence to LS screening recommendations, and communication with relatives. Clinical data were obtained from medical records. Most participants (76%) believed they should undergo colonoscopy every 1-2 years. Only 41% correctly interpreted their genetic tests as uninformative negative or as variant of unknown significance for LS. Less than half had had an upper gastrointestinal endoscopy for screening purpose. Among female participants, 86% had been screened for endometrial cancer (EC) and 71% for ovarian cancer. Most participants had informed relatives about the CRC diagnosis and advised them to undergo CRC screening, but only 50% advised female relatives to be screened for EC and only one-third advised relatives to have genetic counseling. Most CRC survivors with LLS follow the same cancer screening recommended for LS patients but do not understand the meaning of LLS. Greater care must be devoted to communicating the implications of nondiagnostic germline mutation testing among patients with LLS.


Assuntos
Neoplasias Colorretais Hereditárias sem Polipose/psicologia , Detecção Precoce de Câncer/psicologia , Cooperação do Paciente , Percepção , Inquéritos e Questionários , Adulto , Idoso , Neoplasias Colorretais Hereditárias sem Polipose/diagnóstico , Neoplasias Colorretais Hereditárias sem Polipose/genética , Endoscopia Gastrointestinal/psicologia , Feminino , Aconselhamento Genético/psicologia , Testes Genéticos , Humanos , Masculino , Pessoa de Meia-Idade , Risco , Sobreviventes
19.
Leukemia ; 29(3): 668-76, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25151959

RESUMO

Treatment for follicular lymphoma (FL) improved with rituximab. In Sweden, first-line rituximab was gradually introduced between 2003 and 2007, with regional differences. The first national guidelines for FL were published in November 2007, recommending rituximab in first-line therapy. Using the population-based Swedish Lymphoma Registry, 2641 patients diagnosed with FL from 2000 to 2010 were identified and characterized by year and region of diagnosis, age (median, 65 years), gender (50% men), first-line therapy and clinical risk factors. Overall and relative survivals were estimated by calendar periods (2000-2002, 2003-2007 and 2008-2010) and region of diagnosis. With each period, first-line rituximab use and survival increased. Survival was superior in regions where rituximab was quickly adopted and inferior where slowly adopted. These differences were independent in multivariable analyses. Ten-year relative survival for patients diagnosed 2003-2010 was 92%, 83%, 78% and 64% in the age groups 18-49, 50-59, 60-69 and ⩾70, respectively. With increasing rituximab use, male sex emerged as an adverse factor. Survival improved in all patient categories, particularly in elderly women. The introduction and the establishment of rituximab have led to a nationwide improvement in FL survival. However, rituximab might be inadequately dosed in younger women and men of all ages.


Assuntos
Anticorpos Monoclonais Murinos/uso terapêutico , Antineoplásicos/uso terapêutico , Linfoma Folicular/tratamento farmacológico , Sistema de Registros , Adolescente , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Cálculos da Dosagem de Medicamento , Feminino , Humanos , Linfoma Folicular/mortalidade , Linfoma Folicular/patologia , Masculino , Pessoa de Meia-Idade , Guias de Prática Clínica como Assunto , Rituximab , Fatores Sexuais , Análise de Sobrevida , Suécia
20.
Clin Exp Allergy ; 45(2): 384-93, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25469646

RESUMO

BACKGROUND: Although chronic rhinosinusitis with nasal polyps (CRSwNP) is characterized by Th2 inflammation, the mechanism underlying the onset and amplification of this inflammation has not been fully elucidated. Dendritic cells (DCs) are major antigen-presenting cells, central inducers of adaptive immunity and critical regulators of many inflammatory diseases. However, the presence of DCs in CRS, especially in nasal polyps (NPs), has not been extensively studied. OBJECTIVE: The objective of this study was to characterize DC subsets in CRS. METHODS: We used real-time PCR to assess the expression of mRNA for markers of myeloid DCs (mDCs; CD1c), plasmacytoid DCs (pDCs; CD303) and Langerhans cells (LCs; CD1a, CD207) in uncinate tissue (UT) from controls and patients with CRS as well as in NP. We assayed the presence of DCs by immunohistochemistry and flow cytometry. RESULTS: Compared to UT from control subjects (n = 15) and patients with CRS without NP (CRSsNP) (n = 16) and CRSwNP (n = 17), mRNAs for CD1a and CD1c were significantly elevated in NPs (n = 29). In contrast, CD207 mRNA was not elevated in NPs. Immunohistochemistry showed that CD1c(+) cells but not CD303(+) cells were significantly elevated in NPs compared to control subjects or patients with CRSsNP. Flow cytometric analysis showed that CD1a(+) cells in NPs might be a subset of mDC1s and that CD45(+) CD19(-) CD1c(+) CD11c(+) CD141(-) CD303(-) HLA-DR(+) mDC1s and CD45(+) CD19(-) CD11c(+) CD1c(-) CD141(high) HLA-DR(+) mDC2s were significantly elevated in NPs compared to UT from controls and CRSsNP, but CD45(+) CD11c(-) CD303(+) HLA-DR(+) pDCs were only elevated in NPs compared to control UT. CONCLUSION AND CLINICAL RELEVANCE: Myeloid DCs are elevated in CRSwNP, especially in NPs. Myeloid DCs thus may indirectly contribute to the inflammation observed in CRSwNP.


Assuntos
Células Dendríticas/imunologia , Células Mieloides/imunologia , Pólipos Nasais/imunologia , Rinite/imunologia , Sinusite/imunologia , Adulto , Idoso , Antígenos de Superfície/genética , Antígenos de Superfície/metabolismo , Biomarcadores , Doença Crônica , Células Dendríticas/metabolismo , Feminino , Humanos , Imuno-Histoquímica , Imunofenotipagem , Masculino , Pessoa de Meia-Idade , Células Mieloides/metabolismo , Pólipos Nasais/complicações , Pólipos Nasais/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Rinite/complicações , Rinite/metabolismo , Sinusite/complicações , Sinusite/metabolismo , Células Th2/imunologia , Células Th2/metabolismo , Adulto Jovem
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