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1.
J Chem Phys ; 155(15): 154702, 2021 Oct 21.
Artículo en Inglés | MEDLINE | ID: mdl-34686040

RESUMEN

Recent machine learning models for bandgap prediction that explicitly encode the structure information to the model feature set significantly improve the model accuracy compared to both traditional machine learning and non-graph-based deep learning methods. The ongoing rapid growth of open-access bandgap databases can benefit such model construction not only by expanding their domain of applicability but also by requiring constant updating of the model. Here, we build a new state-of-the-art multi-fidelity graph network model for bandgap prediction of crystalline compounds from a large bandgap database of experimental and density functional theory (DFT) computed bandgaps with over 806 600 entries (1500 experimental, 775 700 low-fidelity DFT, and 29 400 high-fidelity DFT). The model predicts bandgaps with a 0.23 eV mean absolute error in cross validation for high-fidelity data, and including the mixed data from all different fidelities improves the prediction of the high-fidelity data. The prediction error is smaller for high-symmetry crystals than for low symmetry crystals. Our data are published through a new cloud-based computing environment, called the "Foundry," which supports easy creation and revision of standardized data structures and will enable cloud accessible containerized models, allowing for continuous model development and data accumulation in the future.

2.
Z Gastroenterol ; 54(1): 44-6, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26751116

RESUMEN

BACKGROUND/OBJECTIVE: Ischemic colitis is a disorder of the intestine arising from a multitude of reasons thus representing a challenge for causal research. Our aim was to shed further light on the course, etiology and triggers of non-occlusive ischemic colitis by presenting an atypical complication after colonoscopy. DESIGN: We present the case report of a 77-year-old male patient presenting with ischemic colitis after an uneventful outpatient colonoscopy two days prior to onset of symptoms. RESULTS: So far only few cases of post-colonoscopy ischemic colitis have been reported. In the present case no single reason was identified. It remains to be assumed that a combination of predisposing conditions with a modest decrease of blood pressure and short-term increased intraluminal pressure during colonoscopy may have led to ischemic colitis. CONCLUSION: Awareness of ischemic colitis as a complication in comparable settings is favorable. So far, early countermeasures against even modest hypotension in patients with comparable past history may be considered on an individual basis depending on the entirety of risk factors. However, prospective studies are necessary to evaluate potential risk profiles for ischemic colitis in terms of colonoscopy.


Asunto(s)
Colitis Isquémica/diagnóstico , Colitis Isquémica/etiología , Colonoscopía/efectos adversos , Anciano , Colitis Isquémica/terapia , Diagnóstico Diferencial , Humanos , Masculino , Resultado del Tratamiento
3.
Z Gastroenterol ; 54(3): 226-30, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-27043885

RESUMEN

OBJECTIVE: Organ failure and local complications contribute to morbidity and mortality in acute pancreatitis. Comorbidity is known to be related to organ failure. The impact of comorbidity on local complications has not yet been delineated. Moreover, it is not clear if the outcome of first-attacks and acute-on-chronic episodes, respectively, differs from outcome in all episodes. METHODS: Consecutive cases of confirmed acute pancreatitis in a four-year period were reviewed. Charlson comorbidity index (CCI), complications (organ failure and local complications), disease severity (according to the revised Atlanta Classification), need for intensive care, and mortality were derived from the charts. RESULTS: A total of 391 episodes of acute pancreatitis were included. Patients with organ failure were significantly older (P< 0.001) und had a higher CCI (P< 0.001) than patients without organ failure. Patients with and without local complications did not significantly differ in age or CCI. The complication rate of the entire cohort (n = 391; 47.1 %) was comparable with the complication rate of first-attacks (n = 269; 46.8 %) and acute-on-chronic episodes (n = 68; 47.1 %). The majority of the twelve deceased patients had been old and/or chronically ill. Six of these patients had an advanced malignant disease. CONCLUSIONS: Comorbidity and age clearly are contributors to organ failure and mortality. Local complications occur independently of age and concomitant diseases. The overall complication rate is not significantly influenced by preceding inflammation of the pancreas. To further improve care in patients with acute pancreatitis special attention should be given to old and multi-morbid patients.


Asunto(s)
Alcoholismo/mortalidad , Enfermedad Crónica/mortalidad , Insuficiencia Multiorgánica/mortalidad , Neoplasias/mortalidad , Pancreatitis/mortalidad , Enfermedad Aguda , Distribución por Edad , Anciano , Causalidad , Estudios de Cohortes , Comorbilidad , Femenino , Alemania/epidemiología , Humanos , Masculino , Persona de Mediana Edad , Insuficiencia Multiorgánica/diagnóstico , Neoplasias/diagnóstico , Pancreatitis/diagnóstico , Factores de Riesgo , Distribución por Sexo , Tasa de Supervivencia
4.
Digit Discov ; 2(5): 1233-1250, 2023 Oct 09.
Artículo en Inglés | MEDLINE | ID: mdl-38013906

RESUMEN

Large-language models (LLMs) such as GPT-4 caught the interest of many scientists. Recent studies suggested that these models could be useful in chemistry and materials science. To explore these possibilities, we organized a hackathon. This article chronicles the projects built as part of this hackathon. Participants employed LLMs for various applications, including predicting properties of molecules and materials, designing novel interfaces for tools, extracting knowledge from unstructured data, and developing new educational applications. The diverse topics and the fact that working prototypes could be generated in less than two days highlight that LLMs will profoundly impact the future of our fields. The rich collection of ideas and projects also indicates that the applications of LLMs are not limited to materials science and chemistry but offer potential benefits to a wide range of scientific disciplines.

5.
Z Gastroenterol ; 50(5): 449-52, 2012 May.
Artículo en Alemán | MEDLINE | ID: mdl-22581699

RESUMEN

Aneurysms within the visceral arteries are rare. Among these, aneurysms of the splenic artery occur most frequently followed by aneurysms of the hepatic arteries. An early diagnosis is easily missed and almost all patients become symptomatic with an acute rupture associated with high mortality. Here we demonstrate the case of a 76-year-old patient who presented with acute upper abdominal pain accompanied by a single episode of vomiting and pyrexia of 39 °C. Laboratory results presented the picture of an obstructive jaundice without evidence for accompanying pancreatitis. Inflammatory markers were within normal limits at onset, but increased dramatically within the next few days. An acute calculous cholecystitis was diagnosed on abdominal ultrasound whereas gastroscopy revealed no relevant changes. Computed tomography was suspicious for pancreatitis of the head with obstruction of the bile duct. Choledocholithiasis was ruled out by ERCP, but symptoms persisted despite papillotomy. Due to raising inflammatory markers and an ongoing impairment of the patients condition, an abdominal CT scan was repeated which revealed the suspicion of a ruptured aneurysm of the common hepatic artery. At the time of transferral we were able to confirm the diagnosis by contrast-enhanced ultrasound and angiography. The patient was immediately forwarded to surgery due to lack of satisfactory endovascular procedures. In summary, the patient suffered from a ruptured spurial aneurysm of the right gastric artery thereby obstructing the common bile duct. Beside CT scans and angiography, this case documents a pivotal role for contrast-enhanced ultrasound in the work-up of visceral artery aneurysms.


Asunto(s)
Aneurisma/complicaciones , Aneurisma/diagnóstico por imagen , Arteria Hepática/diagnóstico por imagen , Ictericia Obstructiva/diagnóstico por imagen , Ictericia Obstructiva/etiología , Anciano , Diagnóstico Diferencial , Humanos , Masculino , Radiografía , Ultrasonografía
6.
Sci Data ; 9(1): 657, 2022 Nov 10.
Artículo en Inglés | MEDLINE | ID: mdl-36357431

RESUMEN

A concise and measurable set of FAIR (Findable, Accessible, Interoperable and Reusable) principles for scientific data is transforming the state-of-practice for data management and stewardship, supporting and enabling discovery and innovation. Learning from this initiative, and acknowledging the impact of artificial intelligence (AI) in the practice of science and engineering, we introduce a set of practical, concise, and measurable FAIR principles for AI models. We showcase how to create and share FAIR data and AI models within a unified computational framework combining the following elements: the Advanced Photon Source at Argonne National Laboratory, the Materials Data Facility, the Data and Learning Hub for Science, and funcX, and the Argonne Leadership Computing Facility (ALCF), in particular the ThetaGPU supercomputer and the SambaNova DataScale® system at the ALCF AI Testbed. We describe how this domain-agnostic computational framework may be harnessed to enable autonomous AI-driven discovery.

7.
Vaccine ; 40(22): 2999-3008, 2022 05 11.
Artículo en Inglés | MEDLINE | ID: mdl-35459556

RESUMEN

BACKGROUND: There is an urgent need for improved influenza vaccines especially for older adults due to the presence of immunosenescence. It is therefore highly relevant to compare enhanced influenza vaccines with traditional influenza vaccines with respect to their effectiveness. OBJECTIVE: To compare vaccine efficacy and effectiveness of adjuvanted influenza vaccines (aTIV/aQIV) vs. non-adjuvanted standard-dose (TIV/QIV) and high-dose (TIV-HD/QIV-HD) influenza vaccines regarding influenza-related outcomes in older adults, complementing findings from the European Centre for Disease Prevention and Control (ECDC)'s systematic review of enhanced seasonal influenza vaccines from February 2020. METHODS: A systematic literature search was conducted in Embase and MEDLINE to identify randomised controlled trials, observational studies and systematic reviews, published since ECDC's systematic review (between 7 February 2020 and 6 September 2021). Included studies were appraised with either the Cochrane Risk of Bias tool, ROBINS-I or AMSTAR 2. RESULTS: Eleven analyses from nine real-world evidence (RWE) studies comprising ∼53 million participants and assessing the relative vaccine effectiveness (rVE) of aTIV vs. TIV, QIV and/or TIV-HD in adults aged ≥65 years over the 2006/07-2008/09 and 2011/12-2019/20 influenza seasons were identified. Nine analyses found that aTIV was significantly more effective than TIV and QIV in reducing influenza-related outcomes by clinical setting and suspected influenza outbreaks (rVE ranging from 7.5% to 25.6% for aTIV vs. TIV and 7.1% to 36.3% for aTIV vs. QIV). Seven analyses found similar effectiveness of aTIV vs. TIV-HD in reducing influenza-related medical encounters, inpatient stays and hospitalisations/emergency room visits. In three analyses, aTIV was significantly more effective than TIV-HD in reducing influenza-related medical encounters and office visits (rVE ranging from 6.6% to 16.6%). Risk of bias of identified studies was moderate to high. CONCLUSIONS: Our study suggests that both adjuvanted and high-dose vaccines are effective alternatives for vaccination programmes in older adults and preferable over conventional standard-dose vaccines.


Asunto(s)
Vacunas contra la Influenza , Gripe Humana , Adyuvantes Inmunológicos , Anciano , Humanos , Gripe Humana/prevención & control , Polisorbatos , Escualeno
8.
Vaccine ; 42(9): 2115-2116, 2024 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-38360472
9.
J Crohns Colitis ; 10(1): 31-7, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26419459

RESUMEN

BACKGROUND AND AIMS: Tacrolimus is recommended for the treatment of steroid-refractory ulcerative colitis (UC). Concomitantly started purine analogues (PAs) are used for the maintenance of remission, though their therapeutic relevance remains uncertain. Here we studied the role of PAs in the long-term outcome of steroid-refractory UC after tacrolimus treatment. METHODS: In five centres, charts of tacrolimus-treated UC patients with a steroid-refractory moderate to severe course were reviewed. Long-term efficacy was determined by colectomy rates and clinical remission in cases of colectomy-free survival for 3 months. RESULTS: We identified 156 patients (median age 34 years) with a median Lichtiger score of 12 (4-17) and pancolitis (E3) in 65% (101). The Kaplan-Meier curve for colectomy-free survival after month 3 showed a benefit in the PA group (p = 0.02). In patients treated with PA clinical remission was achieved in 82% (65/79) vs 67% (39/58) in those not treated with PA (p = 0.02). Time to colectomy was 2 years (median, 0.7-5.8) in the PA group and 0.8 years (0.3-4.7) in the group not treated with PAs (p = 0.02). Time to relapse was 1.2 years (median, 0.3-6.2) in patients with PA treatment and 0.5 years (0.3-3.9) in those without PA treatment (p = 0.05). Overall, clinical remission was achieved in 67% (104/156) of patients. Colectomy was performed in 29% (45/156) 0.5 years (median, 0.04-5.79) after initiation of tacrolimus. Ten (6%) patients had to stop tacrolimus due to adverse events and two (without PA treatment) died. CONCLUSIONS: Our study supports the efficacy of tacrolimus in steroid-refractory UC. Purine analogues appear to be beneficial for the long-term outcome of these patients.


Asunto(s)
Colitis Ulcerosa/tratamiento farmacológico , Mucosa Intestinal/efectos de los fármacos , Mercaptopurina/administración & dosificación , Tacrolimus/administración & dosificación , Adulto , Anciano , Estudios de Cohortes , Colectomía/métodos , Colectomía/estadística & datos numéricos , Colitis Ulcerosa/diagnóstico , Colitis Ulcerosa/mortalidad , Colitis Ulcerosa/cirugía , Colonoscopía/métodos , Bases de Datos Factuales , Quimioterapia Combinada , Femenino , Estudios de Seguimiento , Alemania , Humanos , Inmunosupresores/administración & dosificación , Mucosa Intestinal/patología , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Modelos de Riesgos Proporcionales , Estudios Retrospectivos , Medición de Riesgo , Índice de Severidad de la Enfermedad , Estadísticas no Paramétricas , Esteroides/administración & dosificación , Esteroides/efectos adversos , Tasa de Supervivencia , Factores de Tiempo , Resultado del Tratamiento , Cicatrización de Heridas/efectos de los fármacos , Cicatrización de Heridas/fisiología , Adulto Joven
10.
Genetics ; 152(4): 1407-15, 1999 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-10430571

RESUMEN

The hyperthermophilic archaeon Sulfolobus acidocaldarius exchanges and recombines chromosomal markers by a conjugational mechanism, and the overall yield of recombinants is greatly increased by previous exposure to UV light. This stimulation was studied in an effort to clarify its mechanism and that of marker exchange itself. A variety of experiments failed to identify a significant effect of UV irradiation on the frequency of cell pairing, indicating that subsequent steps are primarily affected, i.e., transfer of DNA between cells or homologous recombination. The UV-induced stimulation decayed rather quickly in parental cells during preincubation at 75 degrees, and the rate of decay depended on the incubation temperature. Preincubation at 75 degrees decreased the yield of recombinants neither from unirradiated parental cells nor from parental suspensions subsequently irradiated. We interpret these results as evidence that marker exchange is stimulated by recombinogenic DNA lesions formed as intermediates in the process of repairing UV photoproducts in the S. acidocaldarius chromosome.


Asunto(s)
Conjugación Genética/efectos de la radiación , Reparación del ADN/efectos de la radiación , ADN de Archaea/efectos de la radiación , Calor , Recombinación Genética/efectos de la radiación , Sulfolobus acidocaldarius/efectos de la radiación , Rayos Ultravioleta , ADN de Archaea/genética , Marcadores Genéticos , Sulfolobus acidocaldarius/genética
11.
Drug Saf ; 5(3): 179-94, 1990.
Artículo en Inglés | MEDLINE | ID: mdl-2190594

RESUMEN

Spinal and epidural blockade are similar in many respects in the anaesthesia they produce, since they both cause major conduction blockade with local anaesthetic agents. Physiologically, the blockade involves the production of a sympathectomy with venous pooling and decreased venous return, causing decreased cardiac output and hypotension. Physiological complications include bradycardia, heart block and, rarely, cardiac arrest. Nonphysiological complications include high or total block from extensive spread of the local anaesthetic agent, and toxic reactions from inadvertent intravenous injection of local anaesthetic during epidural administration. Neurological complications include paraplegia from either haematoma or abscess, arachnoiditis or trauma. Post-dural puncture headache is a persistent problem that is more pronounced in younger patients. Cranial nerve lesions are rarely seen with spinal anaesthesia. This review covers the adverse effects of spinal and epidural blockade and what can be done to prevent and/or treat them. With attention to proper performance and patient selection, spinal and epidural anaesthesia are safe and efficacious options when choosing anaesthetic technique.


Asunto(s)
Anestesia Epidural/efectos adversos , Anestesia Raquidea/efectos adversos , Femenino , Humanos , Embarazo
12.
J Endod ; 26(1): 42-4, 2000 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-11194365

RESUMEN

The purpose of this study was to compare nickel-titanium and stainless-steel spreader penetration in curved canals. Twenty prepared plastic blocks with a 30 degrees curvature were used for each part of the study. In part 1, the force required to insert each spreader to within 1 mm of working length in an empty canal was measured. In part 2, the force required to insert each spreader to within 3 mm of working length was measured in a canal containing a master cone. In part 3, the depth of penetration of each spreader with a master cone in place using a 1.5 kg force was measured. Additionally, in part 3, the depth of penetration of the first accessory cone was measured. The results from part 1 showed that a nickel-titanium spreader required significantly less force than a stainless-steel spreader (0.30 kg vs. 0.59 kg). In part 2, a nickel-titanium spreader required significantly less force than a stainless-steel spreader (1.56 kg vs. 2.42 kg). In part 3, a nickel-titanium spreader penetrated significantly deeper than a stainless-steel spreader (15.0 mm vs. 14.0 mm). There was no significant difference in the depth of penetration of the first accessory cone used after either spreader (0.8 mm vs. 0.7 mm). Therefore, the potential for vertical root fracture in curved canals during lateral condensation may be minimized by using nickel-titanium spreaders.


Asunto(s)
Instrumentos Dentales , Obturación del Conducto Radicular/instrumentación , Cavidad Pulpar/anatomía & histología , Análisis del Estrés Dental , Humanos , Modelos Dentales , Níquel , Acero Inoxidable , Titanio
13.
Aliment Pharmacol Ther ; 37(1): 129-36, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23121200

RESUMEN

BACKGROUND: Steroid-refractory ulcerative colitis (UC) remains a challenging condition warranting surgery upon failure of pharmacological treatment. Calcineurin inhibitors or infliximab are alternatives in this situation. Data on the efficacy and safety of tacrolimus in this setting are limited. AIM: To study the short-term efficacy and safety of tacrolimus in moderate-to-severe steroid-refractory UC. The role of thiopurines in this situation and predictors of colectomy were evaluated. METHODS: In three centers, all charts from tacrolimus-treated patients with steroid-refractory UC were reviewed. Efficacy was assessed by colectomy-free survival and clinical remission at 3 months. RESULTS: We identified 130 patients with pancolitis in 75 (59%), left-sided disease in 35 (27%) and proctitis in 18 patients (14%) (disease localisation not obtainable in two patients). The median age was 40 (range: 18-81). Clinical activity according to the median Lichtiger score decreased from 13 (range: 4-17) at baseline to 3 (0-14) at week 12. Eighteen patients underwent colectomy within the first 3 months of treatment with tacrolimus (14%). Clinical remission was achieved in 94 patients (72%) in this period. Thiopurines given in parallel to tacrolimus tended to limit colectomy and significantly increased remission (P = 0.002) in the short-term. No other predictors of colectomy or remission were identified. Side effects were noticed in 53% of patients and no severe events occurred. CONCLUSION: This large survey confirms the efficacy and safety of tacrolimus in patients with steroid-refractory ulcerative colitis.


Asunto(s)
Colitis Ulcerosa/tratamiento farmacológico , Inmunosupresores/administración & dosificación , Tacrolimus/administración & dosificación , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Colectomía , Femenino , Humanos , Inmunosupresores/efectos adversos , Masculino , Persona de Mediana Edad , Ensayos Clínicos Controlados Aleatorios como Asunto , Inducción de Remisión , Índice de Severidad de la Enfermedad , Tacrolimus/efectos adversos , Factores de Tiempo , Resultado del Tratamiento , Adulto Joven
14.
Aliment Pharmacol Ther ; 31(9): 1036-41, 2010 May.
Artículo en Inglés | MEDLINE | ID: mdl-20175769

RESUMEN

BACKGROUND: The calcineurin inhibitor tacrolimus and the anti-TNF-antibody infliximab are established options in steroid-refractory ulcerative colitis (UC). AIM: To evaluate the efficacy of infliximab-salvage therapy in patients with refractory UC failing to respond to tacrolimus. METHODS: Twenty-four patients were enrolled in this evaluation. Reasons for tacrolimus therapy were steroid-refractory disease in 19 patients and steroid-dependency in five patients. All patients receiving infliximab had tacrolimus-refractory active disease (Lichtiger score >10) and were treated with 5 mg/kg at weeks 0, 2 and 6 and every 8 weeks thereafter, if tolerated. RESULTS: Six of 24 patients (25%) achieved remission following infliximab infusion and four of 24 (17%) had an initial response only, but underwent proctocolectomy later because of loss of response (3) or development of a delayed hypersensitivity reaction (1). Fourteen patients (58%) completely failed to respond with 10 undergoing colectomy. Eight patients experienced side effects under infliximab, including two infectious complications (herpes zoster and herpes pneumonia). CONCLUSIONS: Infliximab offers a therapeutic option as rescue therapy in about a quarter of patients with active UC after failing to respond to tacrolimus. This benefit has to be weighed against the risks of infectious complications.


Asunto(s)
Anticuerpos Monoclonales/uso terapéutico , Colitis Ulcerosa/tratamiento farmacológico , Fármacos Gastrointestinales/uso terapéutico , Adolescente , Adulto , Anciano , Resistencia a Medicamentos , Femenino , Humanos , Infliximab , Masculino , Persona de Mediana Edad , Tacrolimus , Resultado del Tratamiento , Adulto Joven
19.
Aliment Pharmacol Ther ; 29(12): 1230-9, 2009 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-19302074

RESUMEN

BACKGROUND: In severe steroid-refractory Crohn's disease (CD), established therapies fail in a relevant proportion of patients. Recent pilot studies indicated the efficacy of cyclophosphamide pulse therapy in these patients. AIM: To provide further and substantial evidence for the rationale to apply cyclophosphamide pulse therapy as therapeutic option in severe courses of CD. METHODS: Fifteen patients with steroid-refractory (n = 13) or steroid-dependent (n = 2) CD received 2-6 (median 3) monthly pulses of 750 mg cyclophosphamide in an open-label fashion. Eleven patients were on concomitant immunosuppression (azathioprine/mercaptopurine n = 9; methotrexate n = 2). RESULTS: Thirteen of 15 patients (87%) had a clinical response (CDAI decrease >100). Ten patients (67%) went into remission (CDAI <150) after 8 weeks. Steroid-free remission was achieved in eight patients (54%). Two patients (13%) failed to respond. Median CDAI decreased from 420 (245-550) to 100 (26-538) at week 8. Remission lasted 16 months (median, range 4-40). In three patients, arthritis, erythema nodosum and episcleritis completely resolved. Cyclophosphamide pulse therapy administration was well tolerated in all subjects. CONCLUSIONS: Cyclophosphamide pulse therapy is safe and highly effective for induction and maintenance of remission in steroid-refractory/-dependent CD. There is a strong need for additional experience to improve the setting of the encouraging cyclophosphamide treatment in CD.


Asunto(s)
Enfermedad de Crohn/tratamiento farmacológico , Ciclofosfamida/administración & dosificación , Inmunosupresores/administración & dosificación , Adulto , Anciano , Relación Dosis-Respuesta a Droga , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Quimioterapia por Pulso , Inducción de Remisión , Resultado del Tratamiento , Adulto Joven
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