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1.
Nature ; 620(7974): 576-581, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37558874

RESUMO

The flux balances of carbon and chlorine between subduction into the deep mantle and volcanic emissions into the atmosphere are crucial for the habitability of our planet1,2. However, pervasive loss of fluids from subducting slabs has been thought to cut off the delivery of both carbon and chlorine to the deep mantle owing to their high mobility under hydrous conditions3,4. Our new high-pressure experiments show that most carbonates (>75 wt%) in carbonate-rich crustal rocks-one of the main subducting carbon reservoirs-survive devolatilization and hydrous melting in cold and warm subduction zones, indicating that their subduction has driven the deep carbon cycle since the Mesoproterozoic. We found that KCl and NaCl, respectively, become stable phases crystallizing from hydrous carbonatite melts with low chlorine solubility in warm and hot subduction zones, resulting in the sequestration of chlorine in the solid residue in downwelling slabs. Accordingly, the subduction of carbonate-rich rocks facilitated highly effective recycling of both chlorine and carbon into the deep mantle at intermediate stages of Earth's history and led to declining atmospheric pCO2 and the formation of carbon-rich and chlorine-rich mantle reservoirs since the Mesoproterozoic. This period of optimal carbon and chlorine subduction may explain the ages of eclogitic diamonds and the formation of the HIMU mantle source.

2.
Nature ; 582(7810): 67-72, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32494080

RESUMO

Continental rifts are important sources of mantle carbon dioxide (CO2) emission into Earth's atmosphere1-3. Because deep carbon is stored for long periods in the lithospheric mantle4-6, rift CO2 flux depends on lithospheric processes that control melt and volatile transport1,3,7. The influence of compositional and thickness differences between Archaean and Proterozoic lithosphere on deep-carbon fluxes remains untested. Here we propose that displacement of carbon-enriched Tanzanian cratonic mantle concentrates deep carbon below parts of the East African Rift System. Sources and fluxes of CO2 and helium are examined over a 350-kilometre-long transect crossing the boundary between orogenic (Natron and Magadi basins) and cratonic (Balangida and Manyara basins) lithosphere from north to south. Areas of diffuse CO2 degassing exhibit increasing mantle CO2 flux and 3He/4He ratios as the rift transitions from Archaean (cratonic) to Proterozoic (orogenic) lithosphere. Active carbonatite magmatism also occurs near the craton edge. These data indicate that advection of the root of thick Archaean lithosphere laterally to the base of the much thinner adjacent Proterozoic lithosphere creates a zone of highly concentrated deep carbon. This mode of deep-carbon extraction may increase CO2 fluxes in some continental rifts, helping to control the production and location of carbonate-rich magmas.

3.
Molecules ; 27(3)2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-35164243

RESUMO

This mini-review provides coverage of chitosan-based adsorbents and their modified forms as sustainable solid-phase extraction (SPE) materials for precious metal ions, such as gold species, and their complexes in aqueous media. Modified forms of chitosan-based adsorbents range from surface-functionalized systems to biomaterial composites that contain inorganic or other nanomaterial components. An overview of the SPE conditions such as pH, temperature, contact time, and adsorbent dosage was carried out to outline how these factors affect the efficiency of the sorption process, with an emphasis on gold species. This review provides insight into the structure-property relationships for chitinaceous adsorbents and their metal-ion removal mechanism in aqueous media. Cross-linked chitosan sorbents showed a maximum for Au(III) uptake capacity (600 mg/g), while S-containing cross-linked chitosan display favourable selectivity and uptake capacity with Au(III) species. Compared to industrial adsorbents such as activated carbon, modified chitosan sorbents display favourable uptake of Au(III) species, especially in aqueous media at low pH. In turn, this contribution is intended to catalyze further research directed at the rational design of tailored SPE materials that employ biopolymer scaffolds to yield improved uptake properties of precious metal species in aqueous systems. The controlled removal of gold and precious metal species from aqueous media is highly relevant to sustainable industrial processes and environmental remediation.

4.
Lancet Oncol ; 22(10): 1403-1415, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34516954

RESUMO

BACKGROUND: In the primary analysis of the pivotal JULIET trial of tisagenlecleucel, an autologous anti-CD19 chimeric antigen receptor (CAR) T-cell therapy, the best overall response rate was 52% and the complete response rate was 40% in 93 evaluable adult patients with relapsed or refractory aggressive B-cell lymphomas. We aimed to do a long-term follow-up analysis of the clinical outcomes and correlative analyses of activity and safety in the full adult cohort. METHODS: In this multicentre, open-label, single-arm, phase 2 trial (JULIET) done at 27 treatment sites in ten countries (Australia, Austria, Canada, France, Germany, Italy, Japan, the Netherlands, Norway, and the USA), adult patients (≥18 years) with histologically confirmed relapsed or refractory large B-cell lymphomas who were ineligible for, did not consent to, or had disease progression after autologous haematopoietic stem-cell transplantation, with an Eastern Cooperative Oncology Group performance status of 0-1 at screening, were enrolled. Patients received a single intravenous infusion of tisagenlecleucel (target dose 5 × 108 viable transduced CAR T cells). The primary endpoint was overall response rate (ie, the proportion of patients with a best overall disease response of a complete response or partial response using the Lugano classification, as assessed by an independent review committee) at any time post-infusion and was analysed in all patients who received tisagenlecleucel (the full analysis set). Safety was analysed in all patients who received tisagenlecleucel. JULIET is registered with ClinialTrials.gov, NCT02445248, and is ongoing. FINDINGS: Between July 29, 2015, and Nov 2, 2017, 167 patients were enrolled. As of Feb 20, 2020, 115 patients had received tisagenlecleucel infusion and were included in the full analysis set. At a median follow-up of 40·3 months (IQR 37·8-43·8), the overall response rate was 53·0% (95% CI 43·5-62·4; 61 of 115 patients), with 45 (39%) patients having a complete response as their best overall response. The most common grade 3-4 adverse events were anaemia (45 [39%]), decreased neutrophil count (39 [34%]), decreased white blood cell count (37 [32%]), decreased platelet count (32 [28%]), cytokine release syndrome (26 [23%]), neutropenia (23 [20%]), febrile neutropenia (19 [17%]), hypophosphataemia (15 [13%]), and thrombocytopenia (14 [12%]). The most common treatment-related serious adverse events were cytokine release syndrome (31 [27%]), febrile neutropenia (seven [6%]), pyrexia (six [5%]), pancytopenia (three [3%]), and pneumonia (three [3%]). No treatment-related deaths were reported. INTERPRETATION: Tisagenlecleucel shows durable activity and manageable safety profiles in adult patients with relapsed or refractory aggressive B-cell lymphomas. For patients with large B-cell lymphomas that are refractory to chemoimmunotherapy or relapsing after second-line therapies, tisagenlecleucel compares favourably with respect to risk-benefit relative to conventional therapeutic approaches (eg, salvage chemotherapy). FUNDING: Novartis Pharmaceuticals.


Assuntos
Imunoterapia Adotiva , Linfoma Difuso de Grandes Células B/terapia , Receptores de Antígenos de Linfócitos T/uso terapêutico , Linfócitos T/transplante , Austrália , Europa (Continente) , Feminino , Humanos , Imunoterapia Adotiva/efeitos adversos , Imunoterapia Adotiva/mortalidade , Japão , Linfoma Difuso de Grandes Células B/diagnóstico , Linfoma Difuso de Grandes Células B/imunologia , Linfoma Difuso de Grandes Células B/mortalidade , Masculino , Pessoa de Meia-Idade , América do Norte , Intervalo Livre de Progressão , Recidiva , Linfócitos T/imunologia , Fatores de Tempo
5.
Plant Physiol ; 184(2): 607-619, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32764132

RESUMO

RNA interference (RNAi) enables flexible and dynamic interrogation of entire gene families or essential genes without the need for exogenous proteins, unlike CRISPR-Cas technology. Unfortunately, isolation of plants undergoing potent gene silencing requires laborious design, visual screening, and physical separation for downstream characterization. Here, we developed an adenine phosphoribosyltransferase (APT)-based RNAi technology (APTi) in Physcomitrella patens that improves upon the multiple limitations of current RNAi techniques. APTi exploits the prosurvival output of transiently silencing APT in the presence of 2-fluoroadenine, thereby establishing survival itself as a reporter of RNAi. To maximize the silencing efficacy of gene targets, we created vectors that facilitate insertion of any gene target sequence in tandem with the APT silencing motif. We tested the efficacy of APTi with two gene families, the actin-dependent motor, myosin XI (a,b), and the putative chitin receptor Lyk5 (a,b,c). The APTi approach resulted in a homogenous population of transient P. patens mutants specific for our gene targets with zero surviving background plants within 8 d. The observed mutants directly corresponded to a maximal 93% reduction of myosin XI protein and complete loss of chitin-induced calcium spiking in the Lyk5-RNAi background. The positive selection nature of APTi represents a fundamental improvement in RNAi technology and will contribute to the growing demand for technologies amenable to high-throughput phenotyping.


Assuntos
Técnicas Genéticas , Família Multigênica , Interferência de RNA , Adenina Fosforribosiltransferase , Bryopsida , Genes de Plantas
6.
Scand J Gastroenterol ; 55(8): 907-916, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32657179

RESUMO

PURPOSE: Clinical trials have demonstrated efficacy of vedolizumab in ulcerative colitis (UC) and Crohn's disease (CD). Further real-world data is needed to inform clinical practice. The primary outcome was to assess corticosteroid-free and clinical remission after vedolizumab initiation. Secondary outcomes included effect on disease activity scores, biochemical markers, concomitant drug use, endoscopic remission, surgical intervention, hospital admissions and adverse events. MATERIALS AND METHODS: A multi-centre retrospective observational study was conducted with patients initiated on vedolizumab across seven UK hospitals 1/11/14-30/11/16. Clinical disease activity was assessed using the partial Mayo Scores (pMS) and Harvey Bradshaw Index (HBI). Clinical remission was defined as HBI ≤4 or pMS <2 with a combined stool frequency and rectal bleeding sub score of ≤1. Clinical response was defined as ≥2-point decrease from baseline in pMS and ≥3-point decrease from baseline in HBI. RESULTS: One hundred ninety-two patients were included in the final analysis. 45% of UC and 10% of CD patients were anti-TNF naive. Over the observation period corticosteroid-free remission rates for UC and CD were 46% and 45%, while clinical remission rates were 52% and 44%, respectively. Time to corticosteroid free remission for UC and CD was 17.6 [IQR: 8.7-29.6] and 14.1 [QR: 6.0-21.7] weeks, respectively. Time to clinical response for UC was 9.4 [IQR: 5.7-15.4] and CD was 9.5 [IQR: 6.1-18.2] weeks. There was a substantial decrease in the concomitant use of immunomodulators and a similar decrease in concomitant corticosteroid use over the study period. CONCLUSIONS: Results in this predominately anti-TNF experienced population mirror other published real-world data, demonstrating good clinical effectiveness and a comparable safety profile.


Assuntos
Anticorpos Monoclonais Humanizados , Colite Ulcerativa , Doenças Inflamatórias Intestinais , Anticorpos Monoclonais Humanizados/uso terapêutico , Colite Ulcerativa/tratamento farmacológico , Fármacos Gastrointestinais/uso terapêutico , Humanos , Doenças Inflamatórias Intestinais/tratamento farmacológico , Inibidores do Fator de Necrose Tumoral , Reino Unido
7.
Int J Urol ; 26(9): 890-896, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31302930

RESUMO

OBJECTIVES: To describe quality of life outcomes in patients with overactive bladder aged ≥65 years receiving mirabegron, a ß3-adrenoreceptor agonist (BELIEVE). METHODS: BELIEVE was a European, prospective, non-interventional, real-world study of 848 patients with overactive bladder prescribed mirabegron in clinical practice. Overactive bladder questionnaire subscales were prespecified primary end-points, analyzed in the full analysis set (patients completing the questionnaire at baseline and ≥1 follow-up visit) and per protocol set (patients still taking mirabegron at 10-12 months) using accepted standards for minimally important differences (10 points). RESULTS: Nearly half of the patients in the full analysis set (380/796 [47.7%]) and per protocol set (224/452 [49.6%]) were aged ≥65 years. Similar proportions of patients aged ≥65 years (224/407; 55.0%) and <65 years (228/441; 51.7%) were taking mirabegron at 10-12 months. Mean symptom bother scores improved from baseline to month 10-12 in older patients (full analysis set 52.4 to 32.9; per protocol set 51.6 to 30.4) and younger patients (full analysis set 52.2 to 27.4; per protocol set 47.8 to 23.7). Proportions of older/younger patients with improvement in symptom bother were similar (full analysis set 52.1%/52.9%; per protocol set 70.1%/72.4%, respectively). Mean total quality of life scores improved in older patients (full analysis set 60.7-75.9; per protocol set 61.1-77.5) and younger patients (full analysis set 54.9 to 77.6; per protocol set 56.8 to 80.1). No unexpected safety issues were observed. CONCLUSIONS: Patients aged ≥65 years receiving mirabegron in clinical practice reported clinically meaningful improvements in quality of life.


Assuntos
Acetanilidas/uso terapêutico , Agonistas de Receptores Adrenérgicos beta 3/uso terapêutico , Qualidade de Vida , Tiazóis/uso terapêutico , Bexiga Urinária Hiperativa/tratamento farmacológico , Adolescente , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Europa (Continente) , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Inquéritos e Questionários/estatística & dados numéricos , Resultado do Tratamento , Bexiga Urinária Hiperativa/complicações , Bexiga Urinária Hiperativa/psicologia , Adulto Jovem
8.
BJU Int ; 121(2): 289-292, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29171130

RESUMO

OBJECTIVES: To determine the effectiveness of Uromune® in preventing recurrent urinary tract infections (UTIs) in women. PATIENTS AND METHODS: A total of 77 women with microbiology-proven recurrent UTIs were given Uromune sublingual vaccine for a period of 3 months. Time to first UTI recurrence since treatment and adverse events were prospectively recorded in a follow-up period of up to 12 months. RESULTS: Of the 77 women, 75 completed the treatment. Of the 75 women who completed treatment, 59 (78%) had no subsequent UTIs in the follow-up period. Prior to treatment, all women had experienced a minimum of three or more episodes of UTI during the preceding 12 months. Proportionally, the majority of recurrences occurred in postmenopausal women. One patient had to stop treatment because of an adverse event (rash over face and neck). CONCLUSION: This prospective study suggests that Uromune is safe and effective at preventing UTIs in women. Further research is required in larger groups of patients for longer treatment times. An international double-blind randomized control trial comparing Uromune with placebo is currently underway.


Assuntos
Antibacterianos/uso terapêutico , Vacinas Bacterianas/uso terapêutico , Infecções Urinárias/tratamento farmacológico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Antibacterianos/efeitos adversos , Vacinas Bacterianas/efeitos adversos , Toxidermias/etiologia , Feminino , Seguimentos , Humanos , Pessoa de Meia-Idade , Estudos Prospectivos , Recidiva , Prevenção Secundária/métodos , Reino Unido , Adulto Jovem
9.
J Clin Apher ; 32(4): 246-256, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27476033

RESUMO

BACKGROUND: Thrombotic thrombocytopenic purpura (TTP) is a rare disease with 90% mortality if untreated. Since the Canadian Apheresis Group (CAG) trial showed greater survival with therapeutic plasma exchange (TPE) versus plasma infusion, there has been widespread adoption of TPE. Beyond TPE, there is significant practice variation. To characterize this, we developed a survey sent to physicians who might be directly involved in TTP management. METHODS: The survey was sent to CAG members as well as hematologists and nephrologists nationwide and addressed areas of controversy or recognized practice heterogeneity. Descriptive statistics were used to summarize responses, and the χ2 test was used to compare respondents who were and were not CAG physicians. We also compared responses by estimated frequency of TTP cases per year. RESULTS: The CAG response rate was 31% (13 of 42). The survey was sent to 665 non-CAG physicians, of whom 41 responded (6.1%). Though not statistically different, CAG and non-CAG respondents varied regarding use of corticosteroids, aspirin, and venous thromboembolism (VTE) prophylaxis. Significant differences were found between CAG and non-CAG groups regarding cryosupernatant as fluid choice (69.2% vs. 22.5%, P = .004) and the use of TPE tapering (84.6% vs. 51.3%, P = .034), respectively. CONCLUSION: TTP treatment is variable across centres in Canada. Areas of significant variation include the choice of replacement fluid for TPE and whether or not and how to taper TPE. Our survey highlights the practice heterogeneity that exists and identifies areas where more evidence is needed and perhaps where trials should be performed.


Assuntos
Padrões de Prática Médica , Púrpura Trombocitopênica Trombótica/terapia , Canadá , Gerenciamento Clínico , Humanos , Troca Plasmática/métodos , Inquéritos e Questionários
10.
Natl Sci Rev ; 11(6): nwae098, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38933600

RESUMO

Recent advances indicate that the amount of carbon released by gradual degassing from the mantle needs to be revised upwards, whereas the carbon supplied by plumes may have been overestimated in the past. Variations in rock types and oxidation state may be very local and exert strong influences on carbon storage and release mechanisms. Deep subduction may be prevented by diapirism in thick sedimentary packages, whereas carbonates in thinner sequences may be subducted. Carbonates stored in the mantle transition zone will melt when they heat up, recognized by coupled stable isotope systems (e.g. Mg, Zn, Ca). There is no single 'mantle oxygen fugacity', particularly in the thermal boundary layer (TBL) and lowermost lithosphere, where very local mixtures of rock types coexist. Carbonate-rich melts from either subduction or melting of the uppermost asthenosphere trap carbon by redox freezing or as carbonate-rich dykes in this zone. Deeply derived, reduced melts may form further diamond reservoirs, recognized as polycrystalline diamonds associated with websteritic silicate minerals. Carbon is released by either edge-driven convection, which tears sections of the TBL and lower lithosphere down so that they melt by a mixture of heating and oxidation, or by lateral advection of solids beneath rifts. Both mechanisms operate at steps in lithosphere thickness and result in carbonate-rich melts, explaining the spatial association of craton edges and carbonate-rich magmatism. High-pressure experiments on individual rock types, and increasingly on reactions between rocks and melts, are fine-tuning our understanding of processes and turning up unexpected results that are not seen in studies of single rocks. Future research should concentrate on elucidating local variations and integrating these with the interpretation of geophysical signals. Global concepts such as average sediment compositions and a uniform mantle oxidation state are not appropriate for small-scale processes; an increased focus on local variations will help to refine carbon budget models.

11.
Nat Commun ; 15(1): 4311, 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38773097

RESUMO

The oxygen fugacity (fO2) of the lower cratonic lithosphere influences diamond formation, melting mechanisms, and lithospheric evolution, but its redox evolution over time is unclear. We apply Cu isotopes (δ65Cu) of ~ 1.4 Ga lamproites and < 0.59 Ga silica-undersaturated alkaline rocks from the lithosphere-asthenosphere boundary (LAB) of the North Atlantic Craton to characterize fO2 and volatile speciation in their sources. The lamproites' low δ65Cu (-0.19 to -0.12‰) show that the LAB was metal-saturated with CH4 + H2O as the dominant volatiles during the Mesoproterozoic. The mantle-like δ65Cu of the < 0.59 Ga alkaline rocks (0.03 to 0.15‰) indicate that the LAB was more oxidized, stabilizing CO2 + H2O and destabilizing metals. The Neoproterozoic oxidation resulted in an increase of at least 2.5 log units in fO2 at the LAB. Combined with previously reported high fO2 in peridotites from the Slave, Kaapvaal, and Siberia cratonic roots, this oxidation might occur in cratonic roots globally.

12.
Eur Urol Open Sci ; 63: 96-103, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38585593

RESUMO

Background: Recurrent urinary tract infection (rUTI) remains a major health burden for women. A randomized, double-blind, placebo-controlled trial (RCT; NCT02543827) reported that female patients with rUTI receiving a sublingual vaccine, MV140, had a reduction in rUTI and increase in UTI-free rate compared with placebo. Objective: To determine the impact of MV140 on the personal burden of disease in women with rUTI using secondary endpoint data from the pivotal RCT evaluating MV140. Design setting and participants: In the primary RCT, female patients with rUTI enrolled in Spain and UK (from October 2015 to April 2019) were randomized to placebo (6 mo) or MV140 (3 or 6 mo), and followed for 12 mo. Individuals analyzed in this secondary analysis included those in the placebo and 3-mo (recommended dose) groups. Intervention: A polybacterial sublingual vaccine, MV140 (four inactivated whole-cell bacteria-Escherichia coli, Klebsiella pneumoniae, Proteus vulgaris, and Enterococcus faecalis), or placebo. Outcome measurements and statistical analysis: Symptom severity scoring, antibiotic use, safety, and multiple aspects of quality of life (QoL; Short-Form Questionnaire [SF-36]) were assessed. Results and limitations: Compared with the placebo group (n = 76), the 3-mo vaccinated group (n = 74) experienced fewer overall UTI symptoms (mean symptom score 102.2 ± 222.9 vs 194.2 ± 178.8; p = 0.0002), fewer days on antibiotics (12.4 ± 17.7 vs 28.7 ± 25.2; p = 0.0001), and improved total, general, and physical SF-36 QoL improvement (differences in means for total SF-36 score 15.7; 95% confidence interval [CI] 8.80, 22.64; p < 0.0001), with only social function QoL showing no impact (4.07; 95% CI -4.93, 13.08; p = 0.3744). Conclusions: Three months of MV140 is associated with a reduction of the personal burden of UTI by reducing overall UTI symptoms and antibiotic use, improving QoL in women with rUTI. Patient summary: Three months of MV140 vaccine, which has previously been shown to reduce the risk of urinary tract infection safely, is associated with a reduction in the personal burden of disease.

13.
Sci Adv ; 10(12): eadk5979, 2024 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-38517954

RESUMO

We present results from high-pressure, high-temperature experiments that generate incipient carbonate melts at mantle conditions (~90 kilometers depth and temperatures between 750° and 1050°C). We show that these primitive carbonate melts can sequester sulfur in its oxidized form of sulfate, as well as base and precious metals from mantle lithologies of peridotite and pyroxenite. It is proposed that these carbonate sulfur-rich melts may be more widespread than previously thought and that they may play a first-order role in the metallogenic enhancement of localized lithospheric domains. They act as effective agents to dissolve, redistribute, and concentrate metals within discrete domains of the mantle and into shallower regions within Earth, where dynamic physicochemical processes can lead to ore genesis at various crustal depths.

14.
Endosc Int Open ; 12(3): E402-E412, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38504742

RESUMO

Background and study aims The aim of this study was to assess the effect of an educational video on the quality of bowel preparation of patients from a UK population attending for their first colonoscopy. Patients and methods A prospective, endoscopist-blinded trial with 1:1 allocation was performed. Patients referred for their first colonoscopy were recruited between February 2019 and December 2019. All participants were prescribed Moviprep and received the trial site's standard written bowel preparation instructions, with the intervention group also receiving a bespoke educational video. Adequacy of bowel preparation (defined as a Boston Bowel Preparation Scale of ≥2 in each segment of the bowel) and polyp detection rates (PDRs) were compared. Fisher's chi squared test was utilized with P <0.05 as the threshold for significance. Results A total of 509 participants completed the trial from six centers; 251 were randomized to the intervention group. The mean age was 57 years and 52.3% were female. The primary endpoint was met with an adequacy rate of 216 of 251 (86.1%) in the intervention group, compared with 205 of 259 (79.1%) in the control group ( P <0.05, odds ratio [OR] 1.626, 95% CI 1.017-2.614). The PDR was significantly higher in the intervention group (39% vs 30%, OR 1.51, 95% CI 1.04-2.19, P <0.05). Conclusions An educational video leads to improved bowel preparation for patients attending for their first colonoscopy, and is also associated with greater detection of polyps. Widespread adoption of an educational video incurs minimal investment, but would reduce the number of inadequate procedures, missed pathology, and the cost that both these incur.

15.
Sci Bull (Beijing) ; 68(12): 1317-1326, 2023 06 30.
Artigo em Inglês | MEDLINE | ID: mdl-37268441

RESUMO

The Mesozoic terrestrial Jehol Biota of northern China exceeds the biomass and biodiversity of contemporaneous Lagerstätten. From 135 to 120 Ma, biotic radiation may have responded to the peak destruction of the North China Craton. However, the direct mechanistic link between geological and biological evolution is unclear. Phosphorus (P), a bio-essential nutrient, can be supplied by weathering of volcanics in terrestrial ecosystems. The middle-late Mesozoic volcanic-sedimentary sequences of northern China are amazingly rich in terrestrial organisms. Here we demonstrate episodic increases in P delivery, biological productivity, and species abundance in these strata to reveal the coevolution of volcanism and terrestrial biotas. A massive P supply from the weathering of voluminous volcanic products of craton destruction thus supported a terrestrial environment conducive to the high prosperity of the Jehol Biota. During the nascent stage of craton destruction, such volcanic-biotic coupling can also account for the preceding Yanliao Biota with relatively fewer fossils.


Assuntos
Ecossistema , Fósforo , Biota , Evolução Biológica , China
16.
Rev Sci Instrum ; 94(5)2023 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-37219388

RESUMO

The accurate and precise determination of the compositions of silicate glasses formed from melts containing volatile components H2O and CO2 recovered from high-pressure, high-temperature experiments is essential to our understanding of geodynamic processes taking place within the planet. Silicate melts are often difficult to analyze chemically because the formation of quench crystals and overgrowths on silicate phases is rapid and widespread upon quenching of experiments, preventing the formation of glasses in low-SiO2 and volatile-rich compositions. Here, we present experiments conducted in a novel rapid quench piston cylinder apparatus on a series of partially molten low-silica alkaline rock compositions (lamproite, basanite, and calk-alkaline basalt) with a range of water contents between 3.5 and 10 wt %. Quench modification of the volatile-bearing silicate glasses is significantly reduced compared to those produced in older piston cylinder apparatuses. The recovered glasses are almost completely free of quench modification and facilitate the determination of precise chemical compositions. We illustrate significantly improved quench textures and provide an analytical protocol that recovers accurate chemical compositions from both poorly quenched and well-quenched silicate glasses.

17.
Gastroenterology ; 140(5): 1434-43.e1, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21315720

RESUMO

BACKGROUND & AIMS: Patients with irritable bowel syndrome with diarrhea (IBS-D) have increased mucosal serotonin (5-hydroxytryptamine [5-HT]) availability, possibly because immune activation reduces activity of the 5-HT transporter (SERT). We investigated the relationship between mucosal and platelet SERT and immune activation of the duodenal mucosa in patients with IBS-D. METHODS: We quantified mucosal intraepithelial lymphocytes (IELs), mast cells, and enterochromaffin cells in blood samples, measured levels of SERT messenger RNA (mRNA) in mucosal samples, and assessed platelet uptake of 5-HT and platelet membrane binding of (3)H-paroxetine in samples from 29 healthy volunteers (HVs), 20 patients with IBS-D, and 20 untreated patients with celiac disease. RESULTS: Patients with IBS-D or celiac disease had increased numbers of IELs and mast cells compared with HVs (both P < .001). Levels of SERT mRNA were reduced in the mucosa of patients with IBS-D or celiac disease and were inversely correlated with numbers of IELs (r = -0.72, P < .0001). Uptake of 5-HT by platelets from patients with IBS-D or celiac disease was reduced (mean, 17.1 ± 3.5 and 28.3 ± 4.1 nmol·min(-1)·mg(-1), respectively) compared with HVs (50.8 ± 8.0 nmol·min(-1)·mg(-1), P < .01 and P = .05, respectively). Binding of paroxetine to membranes of platelets from patients with IBS-D (median [interquartile range], 226 [92-405] fmol/mg protein) was significantly greater than that from HVs (109 [69-175] fmol/mg protein) and correlated inversely with platelet uptake of 5-HT (r = -0.62, P = .03). Tryptase release from incubated biopsy samples was significantly increased in patients with IBS-D (2.2 [0.42-3.5] vs 0.50 [0.25-0.86] ng·mL(-1)·mg(-1) for HVs; P = .03). CONCLUSIONS: Platelet SERT is reduced in IBS-D and associated with reduced levels of SERT mRNA and duodenal immune activation.


Assuntos
Plaquetas/metabolismo , Duodeno/imunologia , Imunidade Celular , Mucosa Intestinal/imunologia , Síndrome do Intestino Irritável/imunologia , Serotonina/metabolismo , Adulto , Transporte Biológico , Biópsia , Duodeno/metabolismo , Duodeno/patologia , Feminino , Regulação da Expressão Gênica , Humanos , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patologia , Síndrome do Intestino Irritável/metabolismo , Síndrome do Intestino Irritável/patologia , Masculino , Reação em Cadeia da Polimerase , RNA Mensageiro/genética , Proteínas da Membrana Plasmática de Transporte de Serotonina/genética , Proteínas da Membrana Plasmática de Transporte de Serotonina/metabolismo , Transdução de Sinais/fisiologia
18.
NEJM Evid ; 1(4): EVIDoa2100018, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38319200

RESUMO

BACKGROUND: Recurrent urinary tract infections (UTIs), which consist of three or more episodes in 1 year or two or more infections in 6 months, affect 5% to 10% of women. MV140, a sublingual preparation of whole-cell inactivated bacteria, has shown clinical benefit in observational studies. This trial examined treatment with MV140 to prevent recurrent UTI. METHODS: In this multicenter, randomized, double-blind, placebo-controlled, parallel-group 1-year trial, 240 women 18 to 75 years of age from Spain and the United Kingdom with recurrent UTI were allocated to receive MV140 for 3 or 6 months or placebo for 6 months in a 1:1:1 ratio. The primary end point was the number of UTIs in the 9-month study period after 3 months of intervention. Key secondary end points were the percentage of women who were UTI free over the above period, time to UTI onset, and health-related quality of life. RESULTS: The median (interquartile range) of UTI episodes was 3.0 (0.5 to 6.0) for placebo compared with 0.0 (0.0 to 1.0) in both groups receiving MV140 (P<0.001). Among women treated with placebo, 25% (95% confidence interval [CI], 15% to 35%) were free of UTIs compared with 56% (95% CI, 44% to 67%) and 58% (95% CI, 44% to 67%) of women who received 3 and 6 months of MV140 treatment, respectively. A total of 205 AEs in 101 participants were registered (81, 76, and 48 in the placebo, 3-month MV140, and 6-month MV140 groups, respectively). CONCLUSIONS: In this controlled trial of modest size and duration, MV140 showed promising clinical efficacy in reducing recurrent UTI in women suffering from this condition. Adverse effects were not clinically limiting. (Funded by Inmunotek S.L. and Syner-Med [Pharmaceutical Products] Ltd.; ClinicalTrials.gov number, NCT02543827.)

19.
Results Probl Cell Differ ; 70: 375-396, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36348115

RESUMO

The cell cycle is governed by stringent epigenetic mechanisms that, in response to intrinsic and extrinsic regulatory cues, support fidelity of DNA replication and cell division. We will focus on (1) the complex and interdependent processes that are obligatory for control of proliferation and compromised in cancer, (2) epigenetic and topological domains that are associated with distinct phases of the cell cycle that may be altered in cancer initiation and progression, and (3) the requirement for mitotic bookmarking to maintain intranuclear localization of transcriptional regulatory machinery to reinforce cell identity throughout the cell cycle to prevent malignant transformation.


Assuntos
Epigênese Genética , Neoplasias , Humanos , Ciclo Celular/genética , Divisão Celular , Neoplasias/genética , Neoplasias/patologia , Cromatina , Regulação da Expressão Gênica
20.
Results Probl Cell Differ ; 70: 339-373, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36348114

RESUMO

Epigenetic gene regulatory mechanisms play a central role in the biological control of cell and tissue structure, function, and phenotype. Identification of epigenetic dysregulation in cancer provides mechanistic into tumor initiation and progression and may prove valuable for a variety of clinical applications. We present an overview of epigenetically driven mechanisms that are obligatory for physiological regulation and parameters of epigenetic control that are modified in tumor cells. The interrelationship between nuclear structure and function is not mutually exclusive but synergistic. We explore concepts influencing the maintenance of chromatin structures, including phase separation, recognition signals, factors that mediate enhancer-promoter looping, and insulation and how these are altered during the cell cycle and in cancer. Understanding how these processes are altered in cancer provides a potential for advancing capabilities for the diagnosis and identification of novel therapeutic targets.


Assuntos
Epigênese Genética , Neoplasias , Humanos , Fenótipo , Neoplasias/genética , Neoplasias/patologia , Regulação da Expressão Gênica , Cromatina
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