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1.
Endosc Int Open ; 11(10): E952-E962, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37828974

RESUMO

Background and study aims For non-dysplastic Barrett's Esophagus (BE) patients, guidelines recommend endoscopic surveillance every 3 to 5 years with four-quadrant random biopsies every 2 cm of BE length. Adherence to these guidelines is low in clinical practice. Pooling BE surveillance endoscopies on dedicated endoscopy lists performed by dedicated endoscopists could possibly enhance guideline adherence, detection of visible lesions, and dysplasia detection rates (DDRs). Patients and methods Data were used from the ACID-study (Netherlands Trial Registry NL8214), a prospective trial of BE surveillance in the Netherlands. BE patients with known or previously treated dysplasia were excluded. Guideline adherence, detection of visible lesions, and DDRs were compared for patients on dedicated and general endoscopy lists. Results A total of 1,244 patients were included, 318 on dedicated lists and 926 on general lists. Endoscopies on dedicated lists showed significantly higher adherence to the random biopsy protocol (85% vs. 66%, P <0.01) and recommended surveillance intervals (60% vs. 47%, P <0.01) compared to general lists. Detection of visible lesions (8.8% vs. 8.1%, P =0.79) and DDRs were not significantly different (6.9% and 6.6%, P =0.94). None (0.0%) of the patients scheduled on dedicated lists and 10 (1.1%) on general lists were diagnosed with esophageal adenocarcinoma ( P =0.07). In multivariable analysis, dedicated lists were significantly associated with biopsy protocol adherence and adherence to surveillance interval recommendations with odds ratios of 4.45 (95% confidence interval [CI] 2.07-9.57) and 1.64 (95% CI 1.03-2.61), respectively. Conclusions Dedicated endoscopy lists are associated with better adherence to the random biopsy protocol and surveillance interval recommendations.

2.
Nat Commun ; 13(1): 1620, 2022 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-35338120

RESUMO

Light-field driven charge motion links semiconductor technology to electric fields with attosecond temporal control. Motivated by ultimate-speed electron-based signal processing, strong-field excitation has been identified viable for the ultrafast manipulation of a solid's electronic properties but found to evoke perplexing post-excitation dynamics. Here, we report on single-photon-populating the conduction band of a wide-gap dielectric within approximately one femtosecond. We control the subsequent Bloch wavepacket motion with the electric field of visible light. The resulting current allows sampling optical fields and tracking charge motion driven by optical signals. Our approach utilizes a large fraction of the conduction-band bandwidth to maximize operating speed. We identify population transfer to adjacent bands and the associated group velocity inversion as the mechanism ultimately limiting how fast electric currents can be controlled in solids. Our results imply a fundamental limit for classical signal processing and suggest the feasibility of solid-state optoelectronics up to 1 PHz frequency.

3.
Nature ; 573(7773): 235-237, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31511683

RESUMO

The Galactic Centre contains a supermassive black hole with a mass of four million Suns1 within an environment that differs markedly from that of the Galactic disk. Although the black hole is essentially quiescent in the broader context of active galactic nuclei, X-ray observations have provided evidence for energetic outbursts from its surroundings2. Also, although the levels of star formation in the Galactic Centre have been approximately constant over the past few hundred million years, there is evidence of increased short-duration bursts3, strongly influenced by the interaction of the black hole with the enhanced gas density present within the ring-like central molecular zone4 at Galactic longitude |l| < 0.7 degrees and latitude |b| < 0.2 degrees. The inner 200-parsec region is characterized by large amounts of warm molecular gas5, a high cosmic-ray ionization rate6, unusual gas chemistry, enhanced synchrotron emission7,8, and a multitude of radio-emitting magnetized filaments9, the origin of which has not been established. Here we report radio imaging that reveals a bipolar bubble structure, with an overall span of 1 degree by 3 degrees (140 parsecs × 430 parsecs), extending above and below the Galactic plane and apparently associated with the Galactic Centre. The structure is edge-brightened and bounded, with symmetry implying creation by an energetic event in the Galactic Centre. We estimate the age of the bubbles to be a few million years, with a total energy of 7 × 1052 ergs. We postulate that the progenitor event was a major contributor to the increased cosmic-ray density in the Galactic Centre, and is in turn the principal source of the relativistic particles required to power the synchrotron emission of the radio filaments within and in the vicinity of the bubble cavities.

4.
Neth J Med ; 71(6): 308-12, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23956312

RESUMO

BACKGROUND: Routine duodenal biopsies during upper gastrointestinal endoscopy (UGE) have been suggested to be useful in detecting coeliac disease (CD). However results from previous studies are not conclusive. The aim of this study is to investigate the diagnostic yield and cost-effectiveness of routine duodenal biopsy during UGE. METHODS: In this retrospective single-centre study, we studied 6442 patients undergoing first-time UGE at the Rijnstate Hospital, Arnhem, the Netherlands, from January 2009 to December 2010. All UGE reports were analysed for indication, duodenal intubation, and endoscopic aspect of duodenal mucosa. Endomysium and tissue transglutaminase antibody titre, when present, were scored as positive or negative. CD was defined as Marsh 3a or higher. Costs of duodenal biopsies and pathology analysis were calculated. Comparisons were done with T-tests for continuous data and Chi-square tests for categorical data. RESULTS: Forty-one patients had newly diagnosed CD; 34 of these 41 patients had definite indications for biopsy prior to UGE, e.g. positive serology or symptoms. Thus, routine duodenal biopsies identified seven patients as having CD, who otherwise would not have been biopsied. The number needed to biopsy was therefore 577, spending more than v 30,000 per case. CONCLUSIONS: We do not recommend routine duodenal biopsy to screen for coeliac disease because of the high number needed to biopsy as well as high costs.


Assuntos
Biópsia/economia , Doença Celíaca/diagnóstico , Testes Diagnósticos de Rotina/economia , Duodeno/patologia , Adulto , Idoso , Doença Celíaca/patologia , Análise Custo-Benefício , Endoscopia Gastrointestinal , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
5.
Neth J Med ; 67(8): 342-6, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19767664

RESUMO

OBJECTIVE: To test the hypothesis that in young, normotensive obese subjects, physical activity at a fixed, moderate workload, causes a more pronounced hypertensive effect than in lean subjects. PATIENTS AND METHODS: 24 subjects (12 with BMI >30 kg/m(2), 12 with BMI <25 kg/m(2)), underwent a moderate-intensity physical activity protocol (cycling at 100 W). Blood pressure and oxygen consumption were monitored continuously. RESULTS: In the obese subjects, physical activity caused a more pronounced increase in both systolic blood pressure (increase of 40.4 +/- 15.3 mmHg vs 21.2 +/- 10.2 mmHg in lean subjects; p=0.001) and diastolic blood pressure (17.5 +/- 17.9 mmHg vs 3.2 +/- 8.1 mmHg in lean subjects; p=0.02). In regression analyses, these differences were only partly explained by small differences in resting blood pressure. CONCLUSION: Healthy obese subjects show an enhanced prohypertensive response of both systolic and diastolic blood pressure to moderate-intensity physical activity.


Assuntos
Pressão Sanguínea , Exercício Físico/fisiologia , Hipertensão/etiologia , Atividade Motora/fisiologia , Obesidade/complicações , Adulto , Índice de Massa Corporal , Estudos de Casos e Controles , Terapia por Exercício , Feminino , Hemodinâmica , Humanos , Hipertensão/prevenção & controle , Masculino , Análise Multivariada , Obesidade/fisiopatologia , Consumo de Oxigênio , Análise de Regressão , Inquéritos e Questionários
6.
Opt Express ; 15(24): 15892-7, 2007 Nov 26.
Artigo em Inglês | MEDLINE | ID: mdl-19550876

RESUMO

The highest average power that has been achieved with a frequency-shifted feedback modelocked fiber laser is reported. Subpicosecond pulses with 40 kW peak power are obtained by this technique for the first time by using external pulse compression. The pulsing is self starting and environmentally stable. The measured pulse energy in modelocked operation is 120 nJ. The pulses could be compressed to 855 fs. The pulse energy was increased to 1muJ with controlled Q-switched modelocking.

7.
Opt Lett ; 28(11): 890-2, 2003 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-12816236

RESUMO

The Modulation Sideband Technology for Absolute Ranging (MSTAR) sensor permits absolute distance measurement with subnanometer accuracy, an improvement of 4 orders of magnitude over current techniques. The system uses fast phase modulators to resolve the integer cycle ambiguity of standard interferometers. The concept is described and demonstrated over target distances up to 1 m. The design can be extended to kilometer-scale separations.

8.
J Zoo Wildl Med ; 28(4): 386-93, 1997 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9523631

RESUMO

The premise that drugs not be injected into the caudal body of reptiles because they will be carried by the renal portal system to the kidneys, where they may be nephrotoxic or rapidly excreted, was tested by comparing the pharmacokinetics of gentamicin (excreted via glomerular filtration in mammals) and carbenicillin (excreted partly via renal tubular secretion in mammals) following injection into the forelimb or hindlimb of red-eared sliders (Trachemys scripta elegans). Ten sliders received intramuscular gentamicin (10 mg/kg) in a forelimb (n = 5) or a hindlimb (n = 5), and plasma levels of the drug were assayed over time. Following drug clearance, the experiment was repeated with the site of injection reversed so that each animal acted as its own control. Another 10 sliders were similarly treated, using intramuscular carbenicillin (200 mg/kg). Injection site of gentamicin had no effect on any pharmacokinetic parameter (time to maximum plasma concentration, maximum plasma concentration, half-life, area under the curve, clearance, and volume of distribution). However, the area under the curve of plasma carbenicillin concentration vs. time was significantly lower following hindlimb injection, in comparison with forelimb injection, at 1, 4, and 8 hr, which may reflect reduced bioavailability of the drug, as would be expected with renal portal perfusion and tubular excretion on first pass through the kidney. This effect on carbenicillin likely is not clinically important because plasma levels remained above recommended minimum inhibitory concentrations. Because blood draining the caudal body of reptiles passes through the kidneys or the liver before reaching the central circulation, the effect on the pharmacokinetics of a drug injected in that region will vary with its renal or hepatic extraction rate. Generally, this effect is unlikely to be significant.


Assuntos
Antibacterianos/farmacocinética , Carbenicilina/farmacocinética , Gentamicinas/farmacocinética , Rim/irrigação sanguínea , Penicilinas/farmacocinética , Sistema Porta/fisiologia , Tartarugas/metabolismo , Animais , Antibacterianos/administração & dosagem , Área Sob a Curva , Disponibilidade Biológica , Carbenicilina/administração & dosagem , Membro Anterior , Gentamicinas/administração & dosagem , Meia-Vida , Membro Posterior , Injeções Intramusculares/veterinária , Penicilinas/administração & dosagem , Circulação Renal/fisiologia
9.
Can Vet J ; 34(10): 606-10, 1993 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17424305

RESUMO

This study in six cows compared serum concentrations of trimethoprim and sulphadoxine (16 mg/kg body weight (BW)) after once daily and twice daily administration, and of procaine penicillin G (20,000 IU/kg BW) after subcutaneous (SQ) and intramuscular (IM) administration, and evaluated postmortem tissue concentrations of penicillin following SQ treatment. Trimethoprim and penicillin were measured microbiologically, and sulphadoxine colorimetrically. Using minimum inhibitory concentrations (MIC), trimethoprim reached serum concentrations above 0.5 mug/mL from 15 minutes to 120 minutes, and sulphadoxine exceeded 9.5 mug/mL from 10 minutes to 12 hours, after administration. At 24 hours after treatment, both had declined to below the MIC of most organisms. A second treatment at 12 hours maintained concentrations of sulphadoxine above 9.5 mug/mL for a further 24 hours. For penicillin administered IM and SQ, concentrations that peaked at 0.88 mug/mL would inhibit most common grampositive bacteria for the entire 24 hour period and fastidious gram-negative organisms from 90 minutes to 12 hours after SQ treatment, but for virtually the entire period after IM administration. Mean +/- SD concentrations (mug/mL) of penicillin at euthanasia, five days after the last SQ administration, were 1.15 +/- 1.27 (injection site), 1.00 +/- 0.80 (liver), 0.90 +/- 0.58 (renal cortex), 0,58 +/- 0.17 (renal medulla), 0.13 +/- 0.11 (diaphragm), 0.10 +/- 0.08 (gluteal muscle), and 0.06 +/- 0.04 (fat). Therefore, except for the most sensitive organisms, twice daily injection of trimethoprim/sulphadoxine (16 mg/kg BW) may be required. Penicillin G administered SQ at 20,000 IU/kg BW should provide effective serum levels for as long as IM administration against gram-positive organisms, but for only about half as long against gram-negative bacteria. The label withdrawal time of five days cannot be used when penicillin is given SQ at 20,000 IU/kg BW for three days.

11.
Artigo em Francês | MEDLINE | ID: mdl-1665159

RESUMO

Cystic adenoid carcinoma or cylindroma of the breast is a rare tumour, and until new only 140 cases have been described in the literature. The clinical criteria are not very specific: tumour in a woman of 50 years of age, with slow growth, unilateral, well delimited, firm, peri-areolar, painless and not adherent to the skin nor the deep tissues. The diagnosis is made by histological examination which shows the presence of pseudo-cysts encased in cellular masses heaped up, composing epithelium and myo-epithelial elements. These are sometimes visible with optic microscopy, and if necessary confirmed by electron microscopy and using immunohistochemical techniques. It is now realised that the myo-epithelial cell plays a role in the histogenesis of the cylindroma. The outcome is usually good after simple surgical removal which has to be sufficient to avoid local recurrences. All the same there have been rare cases of metastases in the literature which means that these cases should be followed up carefully.


Assuntos
Neoplasias da Mama/patologia , Carcinoma Adenoide Cístico/patologia , Assistência ao Convalescente/métodos , Neoplasias da Mama/epidemiologia , Neoplasias da Mama/cirurgia , Carcinoma Adenoide Cístico/epidemiologia , Carcinoma Adenoide Cístico/cirurgia , Feminino , Humanos , Metástase Linfática , Mastectomia , Pessoa de Meia-Idade , Recidiva Local de Neoplasia
12.
Can J Vet Res ; 54(2): 232-7, 1990 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-2357660

RESUMO

Pasteurella haemolytica A1 culture supernatant containing leukotoxin, and modifiers of cyclic nucleotide and arachidonate metabolism, were evaluated for their ability to alter oxygen radical production by pulmonary alveolar macrophages obtained from seven Holstein calves. Calves were sedated, and underwent bronchoalveolar lavage to harvest macrophages, which were then incubated with culture supernatant and/or the drugs and toxins under study, and challenged with opsonized zymosan to induce oxygen radical generation. This was measured by a chemiluminescence technique. Pasteurella haemolytica A1 culture supernatant alone delayed the time to maximum oxygen radical production, although total production was increased. The cyclooxygenase inhibitor indomethacin and the phospholipase inhibitor p-bromophenacyl bromide significantly reduced maximum oxygen radical production, but their effects were diminished in the presence of culture supernatant. Although forskolin markedly inhibited oxygen radical generation, this effect was not altered by culture supernatant. Incubation of macrophages with pertussis toxin had no effect on oxygen radical production, while incubation with cholera toxin did inhibit production. This inhibitory effect was significantly lessened by concurrent incubation with P. haemolytica A1 culture supernatant.


Assuntos
Macrófagos/metabolismo , Oxigênio/metabolismo , Pasteurella/imunologia , Acetofenonas/farmacologia , Animais , Toxinas Bacterianas/imunologia , Líquido da Lavagem Broncoalveolar/citologia , Bovinos , Células Cultivadas , Toxina da Cólera/farmacologia , Colforsina/farmacologia , Exotoxinas/imunologia , Radicais Livres , Imunossupressores/imunologia , Indometacina/farmacologia , Masculino , Toxina Pertussis , Fatores de Virulência de Bordetella/farmacologia
13.
Artigo em Francês | MEDLINE | ID: mdl-3009601

RESUMO

The authors present 11 cases of Krukenberg tumour and have reviewed the literature concerning this condition. They conclude that the expectation of cure is increased if the primary tumour is removed early and if chemotherapy, hormono-therapy when indicated and immunotherapy are carried out, preferably together. No treatment at present seems to be specific for this condition.


Assuntos
Tumor de Krukenberg , Neoplasias Ovarianas , Adulto , Idoso , Terapia Combinada , Feminino , Humanos , Tumor de Krukenberg/diagnóstico , Tumor de Krukenberg/fisiopatologia , Tumor de Krukenberg/secundário , Tumor de Krukenberg/terapia , Pessoa de Meia-Idade , Neoplasias Ovarianas/diagnóstico , Neoplasias Ovarianas/fisiopatologia , Neoplasias Ovarianas/terapia , Prognóstico
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