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1.
Prostate ; 84(11): 1025-1032, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38704755

RESUMO

BACKGROUND: Prebiopsy magnetic resonance imaging (MRI) increases the detection rate of clinically significant prostate cancer (csPCa). Prostate-specific membrane antigen-positron emission tomography/computed tomography (PSMA PET/CT) maximum standardized uptake value (SUVmax) of the prostate may offer additional value in predicting the likelihood of csPCa in biopsy. METHODS: A single-center cohort study involving patients with biopsy-proven PCa who underwent both MRI and PSMA PET/CT between 2020 and 2021. Logistic regression models were developed for International Society of Urological Pathology (ISUP) Grade Group (GG) ≥ 2 and GG ≥ 3 using noninvasive prebiopsy parameters: age, (log-)prostate-specific antigen (PSA) density, PI-RADS 5 lesion presence, extraprostatic extension (EPE) on MRI, and SUVmax of the prostate. Models with and without SUVmax were compared using Likelihood ratio tests and area under the curve (AUC). DeLong's test was used to compare the AUCs. RESULTS: The study included 386 patients, with 262 (68%) having ISUP GG ≥ 2 and 180 (47%) having ISUP GG ≥ 3. Including SUVmax significantly improved both models' goodness of fit (p < 0.001). The GG ≥ 2 model had a higher AUC with SUVmax 89.16% (95% confidence interval [CI]: 86.06%-92.26%) than without 87.34% (95% CI: 83.93%-90.76%) (p = 0.026). Similarly, the GG ≥ 3 model had a higher AUC with SUVmax 82.51% (95% CI: 78.41%-86.6%) than without 79.33% (95% CI: 74.84%-83.83%) (p = 0.003). The SUVmax inclusion improved the GG ≥ 3 model's calibration at higher probabilities. CONCLUSION: SUVmax of the prostate on PSMA PET/CT potentially improves diagnostic accuracy in predicting the likelihood of csPCa in prostate biopsy.


Assuntos
Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Neoplasias da Próstata , Humanos , Masculino , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/patologia , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Idoso , Pessoa de Meia-Idade , Radioisótopos de Gálio , Isótopos de Gálio , Biópsia , Estudos de Coortes , Imageamento por Ressonância Magnética/métodos , Próstata/patologia , Próstata/diagnóstico por imagem , Gradação de Tumores , Estudos Retrospectivos , Antígeno Prostático Específico/sangue , Valor Preditivo dos Testes
2.
Prostate ; 83(14): 1332-1341, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37455399

RESUMO

INTRODUCTION: Prostate-specific membrane antigen (PSMA) is overexpressed in prostate cancer (PCa). In this study, we aim to immunohistochemically and histopathological validate the fluorine-18 (18 F)-PSMA-1007 positron emission tomography/computed tomography (PET/CT) for intraprostatic PCa lesions. METHODS: Between February 2019 and October 2020, patients with biopsy-proven, treatment-naïve intermediate-to-high-risk PCa undergoing an 18 F-PSMA-1007 PET/CT before robot-assisted radical prostatectomy (RARP) were prospectively enrolled. For all PCa lesions found on whole-mount histopathology, location, size, International Society of Urological Pathology (ISUP) grade group (GG), and immune reactive score (IRS) were assessed after PSMA staining. ISUP GG ≥ 3 PCa was defined as clinically significant (cs) PCa. All lesions were matched on PSMA PET/CT and the maximum standardized uptake value (SUVmax) was measured. RESULTS: A total of 125 lesions were analyzed in the 80 RARP specimens, of which 49 (40%) were csPCa and 76 (60%) non-csPCa. Linear multivariable regressions showed that an increase in SUVmax significantly correlated with a higher ISUP GG (p values between 0.021 and 0.001) and a higher IRS (p = 0.017). Logistic multivariable regression showed that csPCa significantly correlated with a higher SUVmax (odds ratio, OR: 1.17 [95% confidence interval, CI: 1.04-1.21, p = 0.005]), an increase in tumor length (OR: 1.05 [95% CI 1.01-1.10, p = 0.020]) and a higher IRS (OR; 1.24 [95% CI 1.07-1.47, p = 0.006]). A SUVmax threshold of 4 would have resulted in one (2%) missed lesion with csPCa. CONCLUSION: This prospective study revealed that 18 F-PSMA-1007 PET/CT SUVmax is correlated with the ISUP GG and IRS, and thereby could be a tool to characterize intraprostatic PCa lesions.


Assuntos
Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Neoplasias da Próstata , Humanos , Masculino , Oligopeptídeos , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Estudos Prospectivos , Neoplasias da Próstata/patologia , Radioisótopos de Flúor/farmacologia
3.
Am J Physiol Gastrointest Liver Physiol ; 324(4): G281-G294, 2023 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-36749571

RESUMO

Animals involved in common laboratory procedures experience minor levels of stress. The direct effect of limited amounts of stress on gastrointestinal function has not been reported yet. Therefore, this study aimed to assess the effect of single-day and multi-day orogastric gavages on gut physiology in mice. To this end, 12-wk-old female C57Bl6/J mice were randomized to receive treatment with sterile water (200 µL) delivered by orogastric gavages twice daily for a total of 1 or 10 day(s). Control animals did not receive any treatment. Subsequently, gastrointestinal function was assessed by measuring fecal pellet production. Furthermore, ex vivo intestinal barrier and secretory function of the distal colon, proximal colon, and terminal ileum were quantified in Ussing chambers. In mice, single-day gavages did neither influence corticosterone levels nor gastrointestinal function. In mice exposed to multi-day gavages, corticosterone levels were slightly but significantly increased compared with controls after 10 days of treatment. Gastrointestinal motor function was altered, as evidenced by increased fecal pellet counts and a small increase in fecal water content. However, exposure to repeated gavages did not lead to detectable alterations in gastrointestinal barrier function as quantified by the paracellular flux of the probe 4 kDa FITC-dextran as well as transepithelial resistance measurements. Thus, the administration of drugs via single-day or multi-day orogastric gavages leads to no or minor stress in mice, respectively. In both cases, it does not hamper the study of the intestinal barrier function and therefore remains a valuable administration route in preclinical pharmacological research.NEW & NOTEWORTHY Exposure of mice to serial orogastric gavages over the course of 10 days leads to a small but significant increase in plasma corticosterone levels, indicating the presence of a limited amount of stress that is absent after a single-day treatment. This minor stress after multi-day gavages results in increased fecal pellet production and fecal water content in exposed compared with nontreated mice but does not affect the intestinal barrier function in the distal colon, proximal colon, or terminal ileum.


Assuntos
Corticosterona , Mucosa Intestinal , Animais , Feminino , Camundongos , Colo , Corticosterona/farmacologia , Trato Gastrointestinal , Íleo , Permeabilidade
4.
World J Urol ; 40(12): 2919-2924, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36344738

RESUMO

PURPOSE: Nomograms predicting side-specific extraprostatic extension (EPE) may be applied to reduce positive surgical margin (PSM) rates in patients planned for radical prostatectomy (RP). This study evaluates the impact of implementing an externally validated nomogram for side-specific EPE on PSM rate and degree of nerve-sparing. METHODS: In patients planned for RP, the side-specific nomogram predictions (based on MRI, ISUP grade group, and PSA density), with an advised threshold of 20% for safe nerve-sparing, were presented preoperatively to the urological surgeon. The surgeon completed a survey before RP about the planning with respect to side-specific nerve-sparing and change of management due to the result of the nomogram. PSM rates and degree of nerve-sparing were compared to a retrospective control group treated in the months prior to the introduction of the nomogram. RESULTS: A total of 100 patients were included, 50 patients in both groups representing 200 prostate lobes. Of the patients, 37% had histologically confirmed EPE, and 40% a PSM. In 12% of the 100 lobes planned after nomogram presentation, a change in management due to the nomogram was reported. A per-prostate lobe analysis of all the lobes showed comparable rates of full nerve-sparing (45% vs. 30%; p = 0.083) and lower rates of PSM on the lobes with histological EPE (45% vs. 85%; p < 0.05) in the intervention (nomogram) group versus the control group. CONCLUSION: Implementing a predictive nomogram for side-specific EPE in the surgical planning for nerve-sparing leads to lower rates PSM on the side of the histological EPE without compromising nerve-sparing.


Assuntos
Próstata , Neoplasias da Próstata , Masculino , Humanos , Próstata/diagnóstico por imagem , Próstata/cirurgia , Próstata/patologia , Nomogramas , Margens de Excisão , Estudos Retrospectivos , Neoplasias da Próstata/cirurgia , Neoplasias da Próstata/patologia , Prostatectomia/métodos
5.
Nano Lett ; 21(23): 10092-10098, 2021 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-34797661

RESUMO

A requirement for quantum information processors is the in situ tunability of the tunnel rates and the exchange interaction energy within the device. The large energy level separation for atom qubits in silicon is well suited for qubit operation but limits device tunability using in-plane gate architectures, requiring vertically separated top-gates to control tunnelling within the device. In this paper, we address control of the simplest tunnelling device in Si:P, the tunnel junction. Here we demonstrate that we can tune its conductance by using a vertically separated top-gate aligned with ±5 nm precision to the junction. We show that a monolithic 3D epitaxial top-gate increases the capacitive coupling by a factor of 3 compared to in-plane gates, resulting in a tunnel barrier height tunability of 0-186 meV. By combining multiple gated junctions in series we extend our monolithic 3D gating technology to implement nanoscale logic circuits including AND and OR gates.

6.
Gut ; 70(7): 1275-1286, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33023902

RESUMO

OBJECTIVE: Resolvins (RvD1, RvD2 and RvE1) are endogenous anti-inflammatory lipid mediators that display potent analgesic properties in somatic pain by modulating transient receptor potential vanilloid 1 (TRPV1) activation. To what extent these molecules could also have a beneficial effect on TRPV1 sensitisation and visceral hypersensitivity (VHS), mechanisms involved in IBS, remains unknown. DESIGN: The effect of RvD1, RvD2 and RvE1 on TRPV1 activation and sensitisation by histamine or IBS supernatants was assessed on murine dorsal root ganglion (DRG) neurons using live Ca2+ imaging. Based on the results obtained in vitro, we further studied the effect of RvD2 in vivo using a murine model of post-infectious IBS and a rat model of post-inflammatory VHS. Finally, we also tested the effect of RvD2 on submucosal neurons in rectal biopsies of patients with IBS. RESULTS: RvD1, RvD2 and RvE1 prevented histamine-induced TRPV1 sensitisation in DRG neurons at doses devoid of an analgesic effect. Of note, RvD2 also reversed TRPV1 sensitisation by histamine and IBS supernatant. This effect was blocked by the G protein receptor 18 (GPR18) antagonist O-1918 (3-30 µM) and by pertussis toxin. In addition, RvD2 reduced the capsaicin-induced Ca2+ response of rectal submucosal neurons of patients with IBS. Finally, treatment with RvD2 normalised pain responses to colorectal distention in both preclinical models of VHS. CONCLUSIONS: Our data suggest that RvD2 and GPR18 agonists may represent interesting novel compounds to be further evaluated as treatment for IBS.


Assuntos
Hipersensibilidade/tratamento farmacológico , Síndrome do Intestino Irritável/metabolismo , Receptores de Canabinoides/metabolismo , Canais de Cátion TRPV/metabolismo , Adulto , Animais , Capsaicina/farmacologia , Modelos Animais de Doenças , Ácidos Docosa-Hexaenoicos/farmacologia , Ácido Eicosapentaenoico/análogos & derivados , Ácido Eicosapentaenoico/farmacologia , Infecções por Enterobacteriaceae/complicações , Feminino , Gânglios Espinais , Histamina , Humanos , Hipersensibilidade/etiologia , Hipersensibilidade/metabolismo , Inflamação/induzido quimicamente , Inflamação/complicações , Síndrome do Intestino Irritável/tratamento farmacológico , Masculino , Camundongos , Pessoa de Meia-Idade , Neurônios/metabolismo , Ratos
7.
Int J Mol Sci ; 22(19)2021 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-34639054

RESUMO

The protease activity in inflammatory bowel disease (IBD) and irritable bowel syndrome has been studied extensively using synthetic fluorogenic substrates targeting specific sets of proteases. We explored activities in colonic tissue from a 2,4,6-trinitrobenzenesulfonic acid (TNBS)-induced colitis rat model by investigating the cleavage of bioactive peptides. Pure trypsin- and elastase-like proteases on the one hand and colonic tissue from rats with TNBS-induced colitis in the acute or post-inflammatory phase on the other, were incubated with relevant peptides to identify their cleavage pattern by mass spectrometry. An increased cleavage of several peptides was observed in the colon from acute colitis rats. The tethered ligand (TL) sequences of peptides mimicking the N-terminus of protease-activated receptors (PAR) 1 and 4 were significantly unmasked by acute colitis samples and these cleavages were positively correlated with thrombin activity. Increased cleavage of ß-endorphin and disarming of the TL-sequence of the PAR3-based peptide were observed in acute colitis and linked to chymotrypsin-like activity. Increased processing of the enkephalins points to the involvement of proteases with specificities different from trypsin- or chymotrypsin-like enzymes. In conclusion, our results suggest thrombin, chymotrypsin-like proteases and a set of proteases with different specificities as potential therapeutic targets in IBD.


Assuntos
Colite/metabolismo , Peptídeos/metabolismo , Receptores Ativados por Proteinase/metabolismo , Sequência de Aminoácidos , Animais , Biomarcadores , Colite/etiologia , Colite/patologia , Modelos Animais de Doenças , Suscetibilidade a Doenças , Doenças Inflamatórias Intestinais/etiologia , Doenças Inflamatórias Intestinais/metabolismo , Doenças Inflamatórias Intestinais/patologia , Masculino , Peptídeos/química , Proteólise , Ratos , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
8.
Surg Today ; 50(5): 427-439, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31172283

RESUMO

Post-operative sepsis is a severe complication of surgery, which often worsens the clinical outcomes. While several risk factors have been identified, the importance of others remains uncertain. This systematic review and meta-analysis aimed to determine patient and surgery-related risk factors for post-operative sepsis. We reviewed Medline, the Web of Science, and the Cochrane library, systematically, for articles describing risk factors for sepsis. The role of eligible risk factors was investigated using a random-effects model, while analyzing univariate and multivariate data separately. Among 193 pro- and retrospective articles, comprising over 30 million patients, 38 eligible risk factors were selected for this meta-analysis. The patient-related risk factors associated with post-operative sepsis included male gender (odds ratio, OR 1.41), pre-existing heart failure (OR 2.53), diabetes (OR 1.41), and chronic kidney disease (OR 1.26). The surgery-related risk factors identified included emergency surgery (OR 3.38), peri-operative blood transfusion (OR 1.90), inpatient hospital stay (OR 2.31), and open surgery (OR 1.80). The adjusted overall incidence of surgical sepsis was 1.84%. In conclusion, multiple-patient and surgery-related risk factors are associated with the development of post-operative sepsis. Recognizing these risk factors could assist in the pre-operative identification of patients at risk of post-operative sepsis.


Assuntos
Complicações Pós-Operatórias/etiologia , Sepse/etiologia , Transfusão de Sangue , Diabetes Mellitus , Tratamento de Emergência , Feminino , Insuficiência Cardíaca , Humanos , Tempo de Internação , Masculino , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/terapia , Insuficiência Renal Crônica , Fatores de Risco , Sepse/epidemiologia , Sepse/terapia , Fatores Sexuais , Procedimentos Cirúrgicos Operatórios
9.
Lab Invest ; 98(10): 1263-1275, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29326427

RESUMO

Non-alcoholic fatty liver disease (NAFLD) has become the most prevalent chronic liver disease. The presence of portal hypertension has been demonstrated in NAFLD prior to development of inflammation or fibrosis, and is a result of extrahepatic and intrahepatic factors, principally driven by vascular dysfunction. An increased intrahepatic vascular resistance potentially contributes to progression of NAFLD via intralobular hypoxia. However, the exact mechanisms underlying vascular dysfunction in NAFLD remain unknown. This study investigates systemic hemodynamics and both aortic and intrahepatic vascular reactivity in a rat model of severe steatosis. Wistar rats were fed a methionine-choline-deficient diet, inducing steatosis, or control diet for 4 weeks. In vivo hemodynamic measurements, aortic contractility studies, and in situ liver perfusion experiments were performed. The mean arterial blood pressure was lower and portal blood pressure was higher in steatosis compared to controls. The maximal contraction force in aortic rings from steatotic rats was markedly reduced compared to controls. While blockade of nitric oxide (NO) production did not reveal any differences, cyclooxygenase (COX) blockade reduced aortic reactivity in both controls and steatosis, whereas effects were more pronounced in controls. Effects could be attributed to COX-2 iso-enzyme activity. In in situ liver perfusion experiments, exogenous NO donation or endogenous NO stimulation reduced the transhepatic pressure gradient (THPG), whereas NO synthase blockade increased the THPG only in steatosis, but not in controls. Alpha-1-adrenergic stimulation and endothelin-1 induced a significantly more pronounced increase in THPG in steatosis compared to controls. Our results demonstrate that severe steatosis, without inflammation or fibrosis, induces portal hypertension and signs of a hyperdynamic circulation, accompanied by extrahepatic arterial hyporeactivity and intrahepatic vascular hyperreactivity. The arterial hyporeactivity seems to be NO-independent, but appears to be mediated by specific COX-2-related mechanisms. Besides, the increased intrahepatic vascular resistance in steatosis appears not to be NO-related but rather to vasoconstrictor hyperreactivity.


Assuntos
Hipertensão Portal/etiologia , Hepatopatia Gordurosa não Alcoólica/fisiopatologia , Vasoconstrição , Animais , Circulação Hepática , Masculino , Hepatopatia Gordurosa não Alcoólica/complicações , Ratos Wistar
10.
Gut ; 63(12): 1873-82, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24561612

RESUMO

OBJECTIVES: Substantial evidence implicates mast cells and their main constituent histamine in the pathogenesis of visceral hypersensitivity. We explored the specific contribution of histamine H4 (H4R) and H1 (H1R) receptors to visceral hypersensitivity in a postinflammatory rat model. DESIGN: Trinitrobenzenesulfonic acid (TNBS)-colitis was monitored individually by colonoscopy: first on day 3 to confirm the presence of colitis and then every 4 days, starting from day 10, to monitor convalescence and determine the exact timepoint of endoscopic healing in each rat. Experiments were performed 3 days after endoscopic resolution of colitis. Visceral sensitivity was assessed by quantifying visceromotor responses (VMRs) to colorectal distension. Colonic mast cell numbers, histamine release and H4R and H1R mRNA expression were quantified. JNJ7777120 (H4R antagonist) and/or levocetirizine (H1R antagonist) were administered 30 min prior to VMR assessment or histamine release assay. RESULTS: Postcolitis rats displayed a higher number of colonic mast cells, excessive histamine release and significantly enhanced VMRs. Heightened VMRs were dose-dependently reduced by JNJ7777120 and levocetirizine; combined administration of JNJ7777120 and levocetirizine potentiated the antinociceptive effect. In the colon, both H4R and H1R mRNA were present; in the dorsal root ganglia, only H1R mRNA was found. Only colonic H4R mRNA expression was increased in postcolitis rats. Excessive histamine release in postcolitis rats was attenuated by the highest dose of JNJ7777120. CONCLUSIONS: H4R and H1R antagonists dose-dependently reduce and even normalise postinflammatory visceral hypersensitivity via different underlying mechanisms but with a synergistic effect. Both receptor subtypes represent promising targets for the treatment of postinflammatory visceral hypersensitivity.


Assuntos
Colite , Hipersensibilidade , Mucosa Intestinal , Receptores Acoplados a Proteínas G , Receptores Histamínicos H1/metabolismo , Receptores Histamínicos , Regeneração , Animais , Cetirizina/farmacologia , Colite/complicações , Colite/diagnóstico , Colite/etiologia , Colite/metabolismo , Colite/fisiopatologia , Colonoscopia/métodos , Convalescença , Modelos Animais de Doenças , Histamina/metabolismo , Antagonistas não Sedativos dos Receptores H1 da Histamina/farmacologia , Liberação de Histamina/fisiologia , Hipersensibilidade/etiologia , Hipersensibilidade/metabolismo , Hipersensibilidade/fisiopatologia , Hipersensibilidade/terapia , Indóis/farmacologia , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patologia , Masculino , Mastócitos/efeitos dos fármacos , Mastócitos/metabolismo , Piperazinas/farmacologia , Ratos , Ratos Sprague-Dawley , Receptores Acoplados a Proteínas G/antagonistas & inibidores , Receptores Acoplados a Proteínas G/metabolismo , Receptores Histamínicos/metabolismo , Receptores Histamínicos H4 , Regeneração/efeitos dos fármacos , Regeneração/fisiologia , Ácido Trinitrobenzenossulfônico/farmacologia
11.
Stress ; 17(5): 431-44, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25089934

RESUMO

Visceral sensitivity is of pathophysiological importance in abdominal pain disorders and can be modulated by inflammation and stress. However, it is unclear whether inflammation and stress alter visceral perception independently of each other or in conjunction through neuroendocrine interactions. Therefore, we compared the short- and long-term effects of experimental colitis and water avoidance stress (WAS), alone or in combination, on visceral sensitivity in female Wistar rats. Colitis was induced by trinitrobenzene sulfonic acid (TNBS) and colonoscopically confirmed. During WAS, rats were placed on a platform surrounded by water for 1 h. Visceral sensitivity was assessed by quantifying the visceromotor responses (VMRs) to colorectal distension. Activation of the hypothalamic-pituitary-adrenal axis was determined by measuring serum corticosterone in a separate protocol. TNBS instillation resulted in overt colitis, associated with significant visceral hypersensitivity during the acute inflammatory phase (3 days post-TNBS; n = 8/group); after colitis had subsided (28 days post-TNBS), hypersensitivity was resolved (n = 4-8/group). Single WAS was associated with increased VMRs of a magnitude comparable to acute TNBS-induced hypersensitivity (n = 8/group). However, after repetitive WAS no significant hypersensitivity was present (n = 8/group). No additive effect of colitis and stress was seen on visceral pain perception (n = 6-8/group). Corticosterone levels were only increased in acute TNBS-colitis, acute WAS and their combination. To conclude, both colitis and stress successfully induced short-term visceral hypersensitivity and activated the hypothalamic-pituitary-adrenal axis, but long-term effects were absent. In addition, our current findings do not support an additive effect of colitis and stress on visceral sensitivity in female Wistar rats.


Assuntos
Colite/fisiopatologia , Hiperalgesia/fisiopatologia , Estresse Psicológico/fisiopatologia , Dor Visceral/fisiopatologia , Animais , Colite/psicologia , Feminino , Hiperalgesia/psicologia , Ratos , Ratos Wistar , Estresse Psicológico/psicologia , Ácido Trinitrobenzenossulfônico/toxicidade , Dor Visceral/psicologia
12.
Adv Mater ; 36(26): e2312736, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38506626

RESUMO

Spin-orbit interactions arise whenever the bulk inversion symmetry and/or structural inversion symmetry of a crystal is broken providing a bridge between a qubit's spin and orbital degree of freedom. While strong interactions can facilitate fast qubit operations by all-electrical control, they also provide a mechanism to couple charge noise thereby limiting qubit lifetimes. Previously believed to be negligible in bulk silicon, recent silicon nano-electronic devices have shown larger than bulk spin-orbit coupling strengths from Dresselhaus and Rashba couplings. Here, it is shown that with precision placement of phosphorus atoms in silicon along the [110] direction (without inversion symmetry) or [111] direction (with inversion symmetry), a wide range of Dresselhaus and Rashba coupling strength can be achieved from zero to 1113 × 10-13eV-cm. It is shown that with precision placement of phosphorus atoms, the local symmetry (C2v, D2d, and D3d) can be changed to engineer spin-orbit interactions. Since spin-orbit interactions affect both qubit operation and lifetimes, understanding their impact is essential for quantum processor design.

13.
Eur Urol Oncol ; 7(2): 204-210, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37296065

RESUMO

BACKGROUND: The use of clinical parameters, including prebiopsy magnetic resonance imaging (MRI), to decide between active surveillance (AS) and active therapy for prostate cancer (PCa) leads to imperfect selection. Additional prostate-specific membrane antigen (PSMA) positron emission tomography/computed tomography (PET/CT) imaging may improve risk stratification. OBJECTIVE: To study risk stratification and patient selection for AS with the addition of PSMA PET/CT to standard practice. DESIGN, SETTING, AND PARTICIPANTS: A single-centre prospective cohort study (NL69880.100.19) enrolled patients recently diagnosed with PCa who started AS. At diagnosis, all participants had undergone prebiopsy MRI and targeted biopsy for visualised lesions. Patients underwent an additional [68Ga]-PSMA PET/CT and targeted biopsy of all PSMA lesions with a maximum standardised uptake value (SUVmax) of ≥4 not covered by previous biopsies. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: The primary outcome was the number needed to scan (NNS) to detect one patient with upgrading. The study was powered to detect an NNS of 10. Regarding secondary outcomes, univariate logistic regressions analyses were performed on all patients and on the patients who received additional PSMA targeted biopsies on the likelihood of upgrading. RESULTS AND LIMITATIONS: A total of 141 patients were included. Additional PSMA targeted biopsies were performed in 45 (32%) patients. In 13 (9%) patients, upgrading was detected: nine grade group (GG) 2, two GG 3, one GG 4, and one GG 5. The NNS was 11 (95% confidence interval 6-18). Of all participants, PSMA PET/CT and targeted biopsies yielded upgrading most frequently in patients with negative MRI (Prostate Imaging Reporting and Data System [PI-RADS] 1-2). Of patients who received additional PSMA targeted biopsies, upgrading was most frequently found in those with higher prostate-specific antigen density and negative MRI. Limitations included the lack of comparison with standard repeat biopsy, no central review of MRI, and possibility of biopsy sampling error. CONCLUSIONS: PSMA PET/CT can further improve PCa risk stratification and selection for AS patients diagnosed after MRI and targeted biopsies. PATIENT SUMMARY: Prostate-specific membrane antigen positron emission tomography/computed tomography and additional targeted prostate biopsies can identify more aggressive prostate cancer cases previously missed in patients recently started with expectant management for favourable-risk prostate cancer.


Assuntos
Radioisótopos de Gálio , Neoplasias da Próstata , Masculino , Humanos , Neoplasias da Próstata/diagnóstico por imagem , Neoplasias da Próstata/terapia , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada/métodos , Próstata/diagnóstico por imagem , Próstata/patologia , Imageamento por Ressonância Magnética , Estudos Prospectivos , Conduta Expectante
14.
Bio Protoc ; 13(13): e4758, 2023 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-37456337

RESUMO

Myeloperoxidase (MPO) is an enzyme contained in lysosomal azurophilic granules of neutrophils. MPO activity has been shown to correlate with the number of neutrophils in histological sections of the gastrointestinal tract and is therefore accepted as a biomarker of neutrophil invasion in the gut. This protocol describes an easy, cost-effective kinetic colorimetric assay to quantify myeloperoxidase activity in intestinal tissue samples. It is explained using tissue collected in mice but can also be used for other laboratory animals. In a first step, tissue specimens are homogenized using a phosphate buffer containing 0.5% hexadecyltrimethylammonium bromide (HTAB), which extracts MPO from neutrophils. The obtained supernatant is added to a reagent solution containing o-dianisidine dihydrochloride, which is a peroxidase substrate. Finally, the change in absorption is measured via spectrophotometry and converted to a standardized unit of enzyme activity. The assay is illustrated and compared to a commercially available enzyme-linked immunoassay (ELISA), demonstrating that MPO activity does not necessarily correlate with MPO protein expression in tissue samples. Key features Optimized for use in mice and rats but can also be used for samples of other species. Measures enzymatic activity instead of mRNA or protein expression. Requires a spectrophotometer. Can be performed in duplo using 10 mg of (dry-blotted) gut tissue or more. Graphical overview.

15.
Adv Mater ; 35(6): e2201625, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36208088

RESUMO

Phosphorus atoms in silicon offer a rich quantum computing platform where both nuclear and electron spins can be used to store and process quantum information. While individual control of electron and nuclear spins has been demonstrated, the interplay between them during qubit operations has been largely unexplored. This study investigates the use of exchange-based operation between donor bound electron spins to probe the local magnetic fields experienced by the qubits with exquisite precision at the atomic scale. To achieve this, coherent exchange oscillations are performed between two electron spin qubits, where the left and right qubits are hosted by three and two phosphorus donors, respectively. The frequency spectrum of exchange oscillations shows quantized changes in the local magnetic fields at the qubit sites, corresponding to the different hyperfine coupling between the electron and each of the qubit-hosting nuclear spins. This ability to sense the hyperfine fields of individual nuclear spins using the exchange interaction constitutes a unique metrology technique, which reveals the exact crystallographic arrangements of the phosphorus atoms in the silicon crystal for each qubit. The detailed knowledge obtained of the local magnetic environment can then be used to engineer hyperfine fields in multi-donor qubits for high-fidelity two-qubit gates.

16.
J Hand Surg Eur Vol ; 48(5): 466-475, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36524290

RESUMO

This study aimed to quantify forearm kinematics with a focus on the forearm rotation axis. Ten healthy volunteers were included in the study. One three-dimensional computed tomographic scan and two four-dimensional computed tomographic scans were done in all the arms to capture forearm joint motion. After image processing, the rotation axis and the movement of the radius with respect to various axes were quantified. The rotation axis was calculated using finite helical axis analysis and a circle fitting approach. The mean error of the rotation axis found through circle fitting was 0.2 mm (SD 0.1) distally and 0.1 mm (SD 0.1) proximally, indicating an improvement in precision over the finite helical axis approach. The translations of the radius along the ulnar axis and the forearm rotation axis were 2.6 (SD 0.8) and 0.6 mm (SD 0.9), respectively. The rotation of the radius around the radial axis was 7.2°. The techniques presented provide a detailed description of forearm kinematics.


Assuntos
Antebraço , Tomografia Computadorizada Quadridimensional , Humanos , Antebraço/diagnóstico por imagem , Fenômenos Biomecânicos , Pronação , Supinação , Ulna , Rádio (Anatomia)
17.
J Clin Med ; 12(18)2023 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-37762755

RESUMO

High complication rates and surgical revision rates following Aptis implant placement have been reported in the literature. This study evaluates the performance of the Aptis implant of twelve patients using four-dimensional kinematic analysis. The (mean) follow-up was 58 months. Wrist motion, grip strength, and kinematic analysis of both arms were used to investigate possible causes of the reported complications. In nine cases (75%), the proximal to distal translation of the distal radius along the ulnar axis in the affected forearm was too little or absent. Significant correlations were found between postoperative extension and translation of the distal radius along the ulnar axis and between the radial deviation and combined error. The four-dimensional kinematic analysis suggests that the current design of the implant could lead to limited restoration of the position of the forearm rotation axis and the translation of the radius along the ulnar axis.

18.
Cells ; 12(9)2023 04 23.
Artigo em Inglês | MEDLINE | ID: mdl-37174625

RESUMO

Overexpression of the transmembrane mucin MUC13, as seen in inflammatory bowel diseases (IBD), could potentially impact barrier function. This study aimed to explore how inflammation-induced MUC13 disrupts epithelial barrier integrity by affecting junctional protein expression in IBD, thereby also considering the involvement of MUC1. RNA sequencing and permeability assays were performed using LS513 cells transfected with MUC1 and MUC13 siRNA and subsequently stimulated with IL-22. In vivo intestinal permeability and MUC13-related signaling pathways affecting barrier function were investigated in acute and chronic DSS-induced colitis wildtype and Muc13-/- mice. Finally, the expression of MUC13, its regulators and other barrier mediators were studied in IBD and control patients. Mucin knockdown in intestinal epithelial cells affected gene expression of several barrier mediators in the presence/absence of inflammation. IL-22-induced MUC13 expression impacted barrier function by modulating the JAK1/STAT3, SNAI1/ZEB1 and ROCK2/MAPK signaling pathways, with a cooperating role for MUC1. In response to DSS, MUC13 was protective during the acute phase whereas it caused more harm upon chronic colitis. The pathways accounting for the MUC13-mediated barrier dysfunction were also altered upon inflammation in IBD patients. These novel findings indicate an active role for aberrant MUC13 signaling inducing intestinal barrier dysfunction upon inflammation with MUC1 as collaborating partner.


Assuntos
Colite , Doenças Inflamatórias Intestinais , Mucinas , Animais , Camundongos , Colite/induzido quimicamente , Colite/metabolismo , Inflamação/metabolismo , Doenças Inflamatórias Intestinais/metabolismo , Mucosa Intestinal/metabolismo , Mucinas/metabolismo , Quinases Associadas a rho/metabolismo , Interleucina 22
19.
Microbiome ; 11(1): 86, 2023 04 21.
Artigo em Inglês | MEDLINE | ID: mdl-37085819

RESUMO

BACKGROUND AND AIMS: We aimed to identify mucin-microbiome signatures shaping the tumor microenvironment in gastric adenocarcinomas and clinical outcomes. METHODS: We performed high-throughput profiling of the mucin phenotypes present in 108 gastric adenocarcinomas and 20 functional dyspepsia cases using validated mucin-based RT-qPCRs with subsequent immunohistochemistry validation and correlated the data with clinical outcome parameters. The gastric microbiota was assessed by 16S rRNA gene sequencing, taxonomy, and community composition determined, microbial networks analyzed, and the metagenome inferred in association with mucin phenotypes and expression. RESULTS: Gastric adenocarcinomas with an intestinal mucin environment or high-level MUC13 expression are associated with poor survival. On the contrary, gastric MUC5AC or MUC6 abundance was associated with a more favorable outcome. The oral taxa Neisseria, Prevotella, and Veillonella had centralities in tumors with intestinal and mixed phenotypes and were associated with MUC13 overexpression, highlighting their role as potential drivers in MUC13 signaling in GC. Furthermore, dense bacterial networks were observed in intestinal and mixed mucin phenotype tumors whereas the lowest community complexity was shown in null mucin phenotype tumors due to higher Helicobacter abundance resulting in a more decreased diversity. Enrichment of oral or intestinal microbes was mucin phenotype dependent. More specifically, intestinal mucin phenotype tumors favored the establishment of pro-inflammatory oral taxa forming strong co-occurrence networks. CONCLUSIONS: Our results emphasize key roles for mucins in gastric cancer prognosis and shaping microbial networks in the tumor microenvironment. Specifically, the enriched oral taxa associated with aberrant MUC13 expression can be potential biomarkers in predicting disease outcomes. Video Abstract.


Assuntos
Adenocarcinoma , Microbiota , Neoplasias Gástricas , Humanos , Neoplasias Gástricas/genética , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/patologia , Mucina-2/genética , Microambiente Tumoral , RNA Ribossômico 16S/genética , Mucina-6/genética , Fenótipo
20.
ACS Nano ; 17(22): 22601-22610, 2023 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-37930801

RESUMO

Universal quantum computing requires fast single- and two-qubit gates with individual qubit addressability to minimize decoherence errors during processor operation. Electron spin qubits using individual phosphorus donor atoms in silicon have demonstrated long coherence times with high fidelities, providing an attractive platform for scalable quantum computing. While individual qubit addressability has been demonstrated by controlling the hyperfine interaction between the electron and nuclear wave function in a global magnetic field, the small hyperfine Stark coefficient of 0.34 MHz/MV m-1 achieved to date has limited the speed of single quantum gates to ∼42 µs to avoid rotating neighboring qubits due to power broadening from the antenna. The use of molecular 2P qubits with more than one donor atom has not only demonstrated fast (0.8 ns) two-qubit SWAP gates and long spin relaxation times of ∼30 s but provides an alternate way to achieve high selectivity of the qubit resonance frequency. Here, we show in two different devices that by placing the donors with comparable interatomic spacings (∼0.8 nm) but along different crystallographic axes, either the [110] or [310] orientations using STM lithography, we can engineer the hyperfine Stark shift from 1 MHz/MV m-1 to 11.2 MHz/MV m-1, respectively, a factor of 10 difference. NEMO atomistic calculations show that larger hyperfine Stark coefficients of up to ∼70 MHz/MV m-1 can be achieved within 2P molecules by placing the donors ≥5 nm apart. When combined with Gaussian pulse shaping, we show that fast single qubit gates with 2π rotation times of 10 ns and ∼99% fidelity single qubit operations are feasible without affecting neighboring qubits. By increasing the single qubit gate time to ∼550 ns, two orders of magnitude faster than previously measured, our simulations confirm that >99.99% single qubit control fidelities are achievable.

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