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1.
Artículo en Inglés | MEDLINE | ID: mdl-35473713

RESUMEN

OBJECTIVE: To describe a case of functional tremor occurring after a successful MR-guided focused ultrasound thalamotomy (MRgFUS) for essential tremor. METHODS: A 71-year-old right-handed man with essential tremor was referred to us for consideration of deep brain stimulation surgery for worsening bilateral upper limb tremor after a successful left MRgFUS for essential tremor. RESULTS: On clinical exam, signs compatible with a functional tremor were noted, including entertainability and suppressibility. Electrophysiological studies were consistent with essential tremor and superimposed tremor fulfilling the laboratory-supported criteria for functional tremor. DISCUSSION: We describe the first reported case of a functional movement disorder occurring after successful MRgFUS procedure for essential tremor. Recognising this entity and its development after such therapeutic interventions is essential to avoid further unnecessary invasive therapies.

2.
BMC Gastroenterol ; 22(1): 516, 2022 Dec 13.
Artículo en Inglés | MEDLINE | ID: mdl-36513968

RESUMEN

BACKGROUND: T1 colorectal cancer (CRC) without histological high-risk factors for lymph node metastasis (LNM) can potentially be cured by endoscopic resection, which is associated with significantly lower morbidity, mortality and costs compared to radical surgery. An important prerequisite for endoscopic resection as definite treatment is the histological confirmation of tumour-free resection margins. Incomplete resection with involved (R1) or indeterminate (Rx) margins is considered a strong risk factor for residual disease and local recurrence. Therefore, international guidelines recommend additional surgery in case of R1/Rx resection, even in absence of high-risk factors for LNM. Endoscopic full-thickness resection (eFTR) is a relatively new technique that allows transmural resection of colorectal lesions. Local scar excision after prior R1/Rx resection of low-risk T1 CRC could offer an attractive minimal invasive strategy to achieve confirmation about radicality of the previous resection or a second attempt for radical resection of residual luminal cancer. However, oncologic safety has not been established and long-term data are lacking. Besides, surveillance varies widely and requires standardization. METHODS/DESIGN: In this nationwide, multicenter, prospective cohort study we aim to assess feasibility and oncological safety of completion eFTR following incomplete resection of low-risk T1 CRC. The primary endpoint is to assess the 2 and 5 year luminal local tumor recurrence rate. Secondary study endpoints are to assess feasibility, percentage of curative eFTR-resections, presence of scar tissue and/or complete scar excision at histopathology, safety of eFTR compared to surgery, 2 and 5 year nodal and/or distant tumor recurrence rate and 5-year disease-specific and overall-survival rate. DISCUSSION: Since the implementation of CRC screening programs, the diagnostic rate of T1 CRC is steadily increasing. A significant proportion is not recognized as cancer before endoscopic resection and is therefore resected through conventional techniques primarily reserved for benign polyps. As such, precise histological assessment is often hampered due to cauterization and fragmentation and frequently leads to treatment dilemmas. This first prospective trial will potentially demonstrate the effectiveness and oncological safety of completion eFTR for patients who have undergone a previous incomplete T1 CRC resection. Hereby, substantial surgical overtreatment may be avoided, leading to treatment optimization and organ preservation. Trial registration Nederlands Trial Register, NL 7879, 16 July 2019 ( https://trialregister.nl/trial/7879 ).


Asunto(s)
Neoplasias Colorrectales , Recurrencia Local de Neoplasia , Humanos , Cicatriz/complicaciones , Cicatriz/patología , Neoplasias Colorrectales/patología , Metástasis Linfática , Estudios Multicéntricos como Asunto , Recurrencia Local de Neoplasia/patología , Estadificación de Neoplasias , Neoplasia Residual/patología , Estudios Prospectivos , Estudios Retrospectivos , Resultado del Tratamiento
3.
Geophys Res Lett ; 49(13): e2022GL099381, 2022 Jul 16.
Artículo en Inglés | MEDLINE | ID: mdl-35865735

RESUMEN

Following the 15 January 2022 Hunga Tonga-Hunga Ha'apai eruption, several trace gases measured by the Aura Microwave Limb Sounder (MLS) displayed anomalous stratospheric values. Trajectories and radiance simulations confirm that the H2O, SO2, and HCl enhancements were injected by the eruption. In comparison with those from previous eruptions, the SO2 and HCl mass injections were unexceptional, although they reached higher altitudes. In contrast, the H2O injection was unprecedented in both magnitude (far exceeding any previous values in the 17-year MLS record) and altitude (penetrating into the mesosphere). We estimate the mass of H2O injected into the stratosphere to be 146 ± 5 Tg, or ∼10% of the stratospheric burden. It may take several years for the H2O plume to dissipate. This eruption could impact climate not through surface cooling due to sulfate aerosols, but rather through surface warming due to the radiative forcing from the excess stratospheric H2O.

4.
Eur J Appl Physiol ; 122(12): 2575-2583, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36074202

RESUMEN

The objective of this laboratory study was to assess the cardiorespiratory consequences related to the use of different back-support exoskeletons during a repetitive lifting task. Fourteen women and thirteen men performed a dynamic stoop lifting task involving full flexion/extension of the trunk in the sagittal plane. This task was repeated for 5 min with a 10 kg load to handle. Four conditions were tested: with a passive exoskeleton (P-EXO), with two active exoskeletons (A-EXO1 and A-EXO2), as well as without exoskeleton (FREE). The oxygen consumption rate and cardiac costs were measured continuously. Results showed a significantly lower (p < 0.05) oxygen consumption rate for all exoskeletons as compared to FREE (12.6 ± 2.2 ml/kg/min). The values were also significantly lower (p < 0.001) for A-EXO1 (9.1 ± 1.8 ml/kg/min) compared to A-EXO2 (11.0 ± 1.8 ml/kg/min) and P-EXO (11.8 ± 2.4 ml/kg/min). Compared to FREE (59.7 ± 12.9 bpm), the cardiac cost was significantly reduced (p < 0.001) only for A-EXO1 (45.1 ± 11.5 bpm). Several factors can explain these differences on the cardiorespiratory parameters observed between exoskeletons: the technology used (passive vs active), the torque provided by the assistive device, the weight of the system, but also the level of anthropomorphism (related to the number of joints used by the exoskeleton). Our results also highlighted the lack of interaction between the exoskeleton and sex. Thereby, the three back-support exoskeletons tested appeared to reduce the overall physical workload associated with a repetitive lifting task both for men and women.


Asunto(s)
Dispositivo Exoesqueleto , Masculino , Humanos , Femenino , Elevación , Fenómenos Biomecánicos , Torque , Consumo de Oxígeno , Electromiografía/métodos
5.
Clin Exp Dermatol ; 46(4): 663-668, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-33190296

RESUMEN

BACKGROUND: Pachyonychia congenita (PC) is a rare autosomal dominant disorder featuring palmoplantar keratoderma, nail dystrophy, oral leucokeratosis, pilosebaceous cysts and natal teeth. PC results from dominant mutations in one of five genes (KRT6A, KRT6B, KRT6C, KRT16, KRT17) encoding keratin proteins. AIM: To delineate the clinical and genetic features of PC in a series of Israeli patients. METHODS: We used direct sequencing of genomic DNA, and also used cDNA sequencing where applicable. RESULTS: We collected clinical information and molecular data in a cohort of Israeli families diagnosed with PC (n = 16). Most of the patients were Ashkenazi Jews and had a family history of PC. The most common clinical findings were painful focal plantar keratoderma (94%) accompanied by nail dystrophy (81%), pilosebaceous cysts (31%) and prenatal/natal teeth (13%). In contrast to the high prevalence of KRT6A mutations in other populations, we found that KRT16 mutations were the most common type among Israeli patients with PC (56%). Most (77%) of the Israeli patients with PC with KRT16 mutation carried the same variant (c.380G>A; p.R127H) and shared the same haplotype around the KRT16 locus, suggestive of a founder effect. CONCLUSION: The data gleaned from this study emphasizes the importance of population-specific tailored diagnostic strategies.


Asunto(s)
Mutación , Paquioniquia Congénita/epidemiología , Paquioniquia Congénita/genética , Estudios de Cohortes , Femenino , Genética de Población , Genotipo , Humanos , Israel/epidemiología , Masculino , Epidemiología Molecular , Fenotipo
6.
Eur J Appl Physiol ; 121(10): 2811-2823, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34173059

RESUMEN

PURPOSE: Overhead works (OHW) are identified as a major risk factor for shoulder musculoskeletal disorders. The use of upper-limb exoskeletons (EXOUL) is emerging to address these challenges. This research tested the influence of EXOUL design and load on the upper-limb and postural muscles activity, and on the balance control, during OHW. METHODS: This study compared two passive EXOUL, notably differing by the level of assistive torque delivered. Both EXOUL was examined in two load conditions (2 vs. 8 kg). Twenty-nine volunteers performed a static OHW for each condition. RESULTS: Both EXOUL led to similar reductions in shoulder flexor muscle activity (12.3 ± 7.8% of RMSREF), compared to without equipment (29.0 ± 14.2% RMSREF). Both EXOUL resulted in a reduction in the activity of shoulder (3.6 ± 3.2% RMSREF) and wrist (2.4 ± 1.7% RMSREF) extensor muscles (4.9 ± 3.9 and 5.9 ± 6.1% RMSREF, respectively). The use of EXOUL led to reductions in back muscle activity, depending on the exoskeleton design (in % RMSREF, 12.9 ± 9.4 for EXO1, 22.8 ± 12.6 for EXO2 and 32.0 ± 18.4 without equipment). Wearing EXOUL induced changes in balance regulation, depending on both exoskeleton design and load condition. CONCLUSION: The increase of assistive torque was not associated with an increase in EXOUL performance. However, the exoskeleton design (mass, balance, and assistive torque) has to be suitable for the load handled during static OHW to optimize the effects of using an EXOUL on the postural muscles.


Asunto(s)
Adaptación Fisiológica/fisiología , Dispositivo Exoesqueleto , Equilibrio Postural/fisiología , Extremidad Superior/fisiología , Adulto , Fenómenos Biomecánicos/fisiología , Electromiografía/métodos , Femenino , Humanos , Masculino , Adulto Joven
7.
Br J Dermatol ; 182(3): 708-713, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-31777952

RESUMEN

BACKGROUND: Pachyonychia congenita (PC) is a rare autosomal dominant genodermatosis caused by a mutation in any one of five keratin genes (KRT6A, KRT6B, KRT6C, KRT16 or KRT17). Characteristic features of PC are painful palmoplantar keratoderma, variable nail dystrophy, cysts, follicular hyperkeratosis and often oral leukokeratosis. Although oral leukokeratosis can go unnoticed, mucosal involvement of the oral cavity and upper airways can manifest with pain during feeding, hoarseness, stridor and, occasionally, life-threatening obstruction. OBJECTIVES: To characterize patients with PC with symptomatic mucosal involvement. METHODS: We present a case series of nine children with PC with symptomatic mucosal involvement, all with heterozygous mutations in KRT6A. Seven patients complained of painful feeding problems. Four patients were diagnosed with failure to thrive, three of whom required a feeding tube. Simple feeding solutions were beneficial in most cases. Seven patients had laryngeal involvement and one patient died at 4 years of age from acute laryngeal obstruction. CONCLUSIONS: It is important for dermatologists and otolaryngologists to be aware that symptomatic mucosal involvement, and very rarely laryngeal obstruction, can occur in patients with PC. Usually simple feeding solutions may prevent complications and failure to thrive. What's already known about this topic? Pachyonychia congenita (PC) is a rare autosomal dominant genodermatosis due to a mutation in any one of five keratin genes. Symptomatic mucosal involvement is an important clinical feature of PC and appears to be more pronounced in KRT6A mutation carriers. Only leukokeratosis is frequently seen in PC and can be one of the earliest signs of disease. Laryngeal involvement is a less common feature. It might be symptomatic but usually presents as hoarseness, stridor and, occasionally, as a life-threatening respiratory distress. What does this study add? In most cases of laryngeal involvement, there is no need for any intervention. Although pain and feeding difficulties are usually attributed to the oral leukokeratosis, they can be related to a phenomenon called 'first bite syndrome' (FBS). Symptomatic mucosal involvement with feeding difficulty is important but can be managed in most cases with simple feeding solutions (e.g. softer nipple with a larger hole, thicker formula and feeding with a syringe). Linked Comment: Youssefian and Vahidnezhad. Br J Dermatol 2020; 182:536-537.


Asunto(s)
Queratodermia Palmoplantar , Paquioniquia Congénita , Niño , Preescolar , Humanos , Lactante , Queratina-6/genética , Queratinas , Mutación , Paquioniquia Congénita/diagnóstico , Paquioniquia Congénita/genética
8.
Endoscopy ; 52(11): 1014-1023, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-32498100

RESUMEN

BACKGROUND: Endoscopic full-thickness resection (eFTR) is a minimally invasive resection technique that allows definite diagnosis and treatment for complex colorectal lesions ≤ 30 mm unsuitable for conventional endoscopic resection. This study reports clinical outcomes from the Dutch colorectal eFTR registry. METHODS: Consecutive patients undergoing eFTR in 20 hospitals were prospectively included. The primary outcome was technical success, defined as macroscopic complete en bloc resection. Secondary outcomes were: clinical success, defined as tumor-free resection margins (R0 resection); full-thickness resection rate; and adverse events. RESULTS : Between July 2015 and October 2018, 367 procedures were included. Indications were difficult polyps (non-lifting sign and/or difficult location; n = 133), primary resection of suspected T1 colorectal cancer (CRC; n = 71), re-resection after incomplete resection of T1 CRC (n = 150), and subepithelial tumors (n = 13). Technical success was achieved in 308 procedures (83.9 %). In 21 procedures (5.7 %), eFTR was not performed because the lesion could not be reached or retracted into the cap. In the remaining 346 procedures, R0 resection was achieved in 285 (82.4 %) and full-thickness resection in 288 (83.2 %). The median diameter of resected specimens was 23 mm. Overall adverse event rate was 9.3 % (n = 34/367): 10 patients (2.7 %) required emergency surgery for five delayed and two immediate perforations and three cases of appendicitis. CONCLUSION : eFTR is an effective and relatively safe en bloc resection technique for complex colorectal lesions with the potential to avoid surgery. Further studies assessing the role of eFTR in early CRC treatment with long-term outcomes are needed.


Asunto(s)
Neoplasias Colorrectales , Neoplasias Colorrectales/cirugía , Endoscopía , Humanos , Sistema de Registros , Estudios Retrospectivos , Resultado del Tratamiento
9.
Geophys Res Lett ; 47(24): e2020GL090131, 2020 Dec 28.
Artículo en Inglés | MEDLINE | ID: mdl-33518832

RESUMEN

Convectively injected water vapor (H2O) in the North American (NA) summer lowermost stratosphere results in significant outliers in the 100-hPa H2O measurements from the Aura Microwave Limb Sounder (MLS). MLS statistics from 15 years confirm that the NA region contains over 60% of global 100-hPa H2O > 12 ppmv, despite having only ∼1.8% of all MLS observations. A profile sampled in August 2019 stands out, with H 2 O = 26 . 3 ppmv, far exceeding the prior record and the median ∼4.5-ppmv abundance in NA. This particular outlier is associated with a large overshooting convective event (OCE) that spanned multiple U.S. states and persisted for several hours. Colocation of the MLS data over NA with cloud observations from Aqua's Moderate Resolution Imaging Spectroradiometer (MODIS) reveals the unique character of this case, as only 2.3% of MLS profiles are as close to an OCE and only 0.024% of OCEs cover as large an area within a 500-km perimeter of a profile.

10.
Nervenarzt ; 91(8): 700-707, 2020 Aug.
Artículo en Alemán | MEDLINE | ID: mdl-32642945

RESUMEN

In the past few decades, research on pain and placebo analgesia has gained importance both scientifically and clinically. In this article, the current findings and focus of research as well as the significance of placebo research for assessing the effectiveness of pain medication are illustrated. The underlying mechanisms of placebo analgesia not only have implications for theoretical models but also offer clinically relevant guidelines for everyday interventions in pain treatment. However, many placebo phenomena are not fully understood and have to be investigated further in order to exploit the full potential of placebo effects. Interindividual differences and their inclusion in treatment will play a major role in this aspect.


Asunto(s)
Analgesia , Efecto Placebo , Humanos , Dolor/tratamiento farmacológico , Manejo del Dolor
11.
BMC Surg ; 19(1): 93, 2019 Jul 16.
Artículo en Inglés | MEDLINE | ID: mdl-31311545

RESUMEN

BACKGROUND: This study assessed clinical outcomes, including safety and recurrence, from the two-year follow-up of patients who underwent open ventral primary hernia repair with the use of the Parietex™ Composite Ventral Patch (PCO-VP). METHODS: A prospective single-arm, multicenter study of 126 patients undergoing open ventral hernia repair for umbilical and epigastric hernias with the PCO-VP was performed. RESULTS: One hundred twenty-six subjects (110 with umbilical hernia and 16 with epigastric hernia) with a mean hernia diameter of 1.8 cm (0.4-4.0) were treated with PCO-VP. One hundred subjects completed the two-year study. Cumulative hernia recurrence was 3.0% (3/101; 95%CI: 0.0-6.3%) within 24 months. Median Numeric Rating Scale pain scores improved from 2 [0-10] at baseline to 0 [0-3] at 1 month (P < 0.001) and remained low at 24 months 0 [0-6] (P < 0.001). 99% (102/103) of the patients were satisfied with their repair at 24 months postoperative. CONCLUSIONS: The use of PCO-VP to repair primary umbilical and epigastric defects yielded a low recurrence rate, low postoperative and chronic pain, and high satisfaction ratings, confirming that PCO-VP is effective for small ventral hernia repair in the two-year term after implantation. TRIAL REGISTRATION: The study was registered publically at clinicaltrials.gov ( NCT01848184 registered May 7, 2013).


Asunto(s)
Hernia Ventral/cirugía , Herniorrafia/instrumentación , Complicaciones Posoperatorias/epidemiología , Mallas Quirúrgicas , Adulto , Anciano , Femenino , Estudios de Seguimiento , Herniorrafia/efectos adversos , Humanos , Masculino , Persona de Mediana Edad , Satisfacción del Paciente , Estudios Prospectivos , Recurrencia
12.
Am J Gastroenterol ; 113(5): 677-685, 2018 05.
Artículo en Inglés | MEDLINE | ID: mdl-29681624

RESUMEN

OBJECTIVES: Studies on the impact of rapid on-site evaluation (ROSE) during endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) of lymph nodes are retrospective and have shown conflicting results. We aimed to compare the diagnostic yield of EUS-FNA of lymph nodes with ROSE (ROSE+) and without ROSE (ROSE-). METHODS: This was a multicenter, randomized controlled trial. Consecutive patients who were scheduled to undergo EUS-FNA of mediastinal or abdominal lymph nodes were randomized to ROSE+ or ROSE-. In the ROSE+ group, the number of passes was dictated by the on-site cytotechnician. In the ROSE- group, five passes were performed without interference from the cytotechnician. All samples were reviewed by a single-expert cytopathologist, blinded to group allocation. Primary endpoint was diagnostic yield with and without ROSE. RESULTS: After inclusion of 90 patients, interim analysis showed futility of study continuation since diagnostic yield of ROSE+ and ROSE- were comparable. A total of 91 patients were randomized to ROSE+ (N = 45) or ROSE- (N = 46). Diagnostic yield of ROSE+ and ROSE- and diagnostic accuracy were comparable: 93.3% vs. 95.7% (P = 0.68) and 97.6% vs. 93.2% (P = 0.62), respectively. Two major complications (one per group) occurred (p = 0.99). ROSE- patients more often reported self-limiting post-procedural pain (p < 0.001). Median procedure time for ROSE+ (20 min) and ROSE- (23 min) was comparable (P = 0.06). Median time to review slides in the ROSE- group (12:47 min) was longer than with ROSE+ (7:52 min) (P < 0.001). Mean costs of ROSE- and ROSE+ were comparable: €938.29 (±172.70) vs. €945.98 (±223.38) (P = 0.91), respectively. CONCLUSIONS: Diagnostic yield and accuracy of EUS-FNA of mediastinal and abdominal lymph nodes with and without ROSE are comparable. Time needed to review slides was shorter and post-procedural pain was less often reported in the ROSE+ group. Based on the primary outcome, the implementation of ROSE during EUS-FNA of mediastinal and abdominal lymph nodes cannot be advised. (Dutch Trial Register: NTR4876).


Asunto(s)
Ganglios Linfáticos/patología , Metástasis Linfática/diagnóstico , Neoplasias Pancreáticas/patología , Abdomen , Adulto , Anciano , Biopsia por Aspiración con Aguja Fina Guiada por Ultrasonido Endoscópico , Femenino , Humanos , Metástasis Linfática/patología , Masculino , Mediastino , Persona de Mediana Edad , Países Bajos , Estudios Retrospectivos , Factores de Tiempo
13.
Br J Dermatol ; 178(2): 502-508, 2018 02.
Artículo en Inglés | MEDLINE | ID: mdl-28922471

RESUMEN

BACKGROUND: Dowling-Degos disease (DDD), featuring reticulate pigmentation, and familial hidradenitis suppurativa (HS) share many clinical features including autosomal dominant inheritance, flexural location and follicular defects. The coexistence of the two disorders was recently found to result from mutations in PSENEN, encoding the γ-secretase subunit protein presenilin enhancer. OBJECTIVES: To investigate PSENEN mutations in a series of four unrelated patients who presented with combined DDD and HS. METHODS: Mutation and haplotype analysis of PSENEN by polymerase chain reaction, and cellular assays investigating the Notch signalling pathway. RESULTS: Here we report four families of Jewish Ashkenazi origin who presented with clinical features characteristic of both disorders. All patients were found to carry the same, heterozygous mutation in PSENEN (c.168T>G, p.Y56X). Haplotype analysis revealed that the mutation originated from a common ancestor. Genes associated with DDD, as well as HS, have been shown to encode important regulators of Notch signalling. Accordingly, using a reporter assay, we demonstrated decreased Notch activity in a patient's keratinocytes. CONCLUSIONS: The present data confirm the genetic basis of the combined DDD-HS phenotype and suggest that Notch signalling may play a central role in the pathogenesis of this rare condition.


Asunto(s)
Secretasas de la Proteína Precursora del Amiloide/genética , Efecto Fundador , Hidradenitis Supurativa/genética , Hiperpigmentación/genética , Proteínas de la Membrana/genética , Mutación/genética , Enfermedades Cutáneas Genéticas/genética , Enfermedades Cutáneas Papuloescamosas/genética , Adulto , Femenino , Humanos , Masculino , Fenotipo , Receptores Notch/genética , Transducción de Señal/genética , Adulto Joven
14.
Analyst ; 143(3): 593-605, 2018 Jan 29.
Artículo en Inglés | MEDLINE | ID: mdl-29260151

RESUMEN

Modern quantum technology currently experiences extensive advances in applicability in communications, cryptography, computing, metrology and lithography. Harnessing this technology platform for chem/bio sensing scenarios is an appealing opportunity enabling ultra-sensitive detection schemes. This is further facilliated by the progress in fabrication, miniaturization and integration of visible and infrared quantum photonics. Especially, the combination of efficient single-photon sources together with waveguiding/sensing structures, serving as active optical transducer, as well as advanced detector materials is promising integrated quantum photonic chem/bio sensors. Besides the intrinsic molecular selectivity and non-destructive character of visible and infrared light based sensing schemes, chem/bio sensors taking advantage of non-classical light sources promise sensitivities beyond the standard quantum limit. In the present review, recent achievements towards on-chip chem/bio quantum photonic sensing platforms based on N00N states are discussed along with appropriate recognition chemistries, facilitating the detection of relevant (bio)analytes at ultra-trace concentration levels. After evaluating recent developments in this field, a perspective for a potentially promising sensor testbed is discussed for reaching integrated quantum sensing with two fiber-coupled GaAs chips together with semiconductor quantum dots serving as single-photon sources.


Asunto(s)
Técnicas Biosensibles , Óptica y Fotónica , Puntos Cuánticos , Rayos Infrarrojos , Luz , Fotones , Semiconductores
15.
Nature ; 485(7399): 494-7, 2012 May 02.
Artículo en Inglés | MEDLINE | ID: mdl-22622576

RESUMEN

Warming experiments are increasingly relied on to estimate plant responses to global climate change. For experiments to provide meaningful predictions of future responses, they should reflect the empirical record of responses to temperature variability and recent warming, including advances in the timing of flowering and leafing. We compared phenology (the timing of recurring life history events) in observational studies and warming experiments spanning four continents and 1,634 plant species using a common measure of temperature sensitivity (change in days per degree Celsius). We show that warming experiments underpredict advances in the timing of flowering and leafing by 8.5-fold and 4.0-fold, respectively, compared with long-term observations. For species that were common to both study types, the experimental results did not match the observational data in sign or magnitude. The observational data also showed that species that flower earliest in the spring have the highest temperature sensitivities, but this trend was not reflected in the experimental data. These significant mismatches seem to be unrelated to the study length or to the degree of manipulated warming in experiments. The discrepancy between experiments and observations, however, could arise from complex interactions among multiple drivers in the observational data, or it could arise from remediable artefacts in the experiments that result in lower irradiance and drier soils, thus dampening the phenological responses to manipulated warming. Our results introduce uncertainty into ecosystem models that are informed solely by experiments and suggest that responses to climate change that are predicted using such models should be re-evaluated.


Asunto(s)
Calentamiento Global , Modelos Biológicos , Periodicidad , Fenómenos Fisiológicos de las Plantas , Incertidumbre , Artefactos , Ecosistema , Flores/crecimiento & desarrollo , Flores/fisiología , Desarrollo de la Planta , Hojas de la Planta/crecimiento & desarrollo , Hojas de la Planta/fisiología , Plantas/clasificación , Reproducibilidad de los Resultados , Suelo/química , Temperatura , Factores de Tiempo
16.
Am J Gastroenterol ; 112(5): 785-796, 2017 05.
Artículo en Inglés | MEDLINE | ID: mdl-28323275

RESUMEN

OBJECTIVES: The decision to perform secondary surgery after endoscopic resection of T1 colorectal cancer (CRC) depends on the risk of lymph node metastasis and the risk of incomplete resection. We aimed to examine the incidence and risk factors for incomplete endoscopic resection of T1 CRC after a macroscopic radical endoscopic resection. METHODS: Data from patients treated between 2000 and 2014 with macroscopic complete endoscopic resection of T1 CRC were collected from 13 hospitals. Incomplete resection was defined as local recurrence at the polypectomy site during follow-up or malignant tissue in the surgically resected specimen in case secondary surgery was performed. Multivariate regression analysis was performed to analyze factors associated with incomplete resection. RESULTS: In total, 877 patients with a median follow-up time of 36.5 months (interquartile range 16.0-68.3) were included, in whom secondary surgery was performed in 358 patients (40.8%). Incomplete resection was observed in 30 patients (3.4%; 95% confidence interval (CI) 2.3-4.6%). Incomplete resection rate was 0.7% (95% CI 0-2.1%) in low-risk T1 CRC vs. 4.4% (95% CI 2.7-6.5%) in high-risk T1 CRC (P=0.04). Overall adverse outcome rate (incomplete resection or metastasis) was 2.1% (95% CI 0-5.0%) in low-risk T1 CRC vs. 11.7% (95% CI 8.8-14.6%) in high-risk T1 CRC (P=0.001). Piecemeal resection (adjusted odds ratio 2.60; 95% CI 1.20-5.61, P=0.02) and non-pedunculated morphology (adjusted odds ratio 2.18; 95% CI 1.01-4.70, P=0.05) were independent risk factors for incomplete resection. Among patients in whom no additional surgery was performed, who developed recurrent cancer, 41.7% (95% CI 20.8-62.5%) died as a result of recurrent cancer. CONCLUSIONS: In the absence of histological high-risk factors, a 'wait-and-see' policy with limited follow-up is justified. Piecemeal resection and non-pedunculated morphology are independent risk factors for incomplete endoscopic resection of T1 CRC.


Asunto(s)
Adenocarcinoma/cirugía , Neoplasias Colorrectales/cirugía , Recurrencia Local de Neoplasia/etiología , Recurrencia Local de Neoplasia/patología , Adenocarcinoma/secundario , Anciano , Colectomía , Colonoscopía , Neoplasias Colorrectales/patología , Femenino , Estudios de Seguimiento , Humanos , Metástasis Linfática , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia/cirugía , Estadificación de Neoplasias , Neoplasia Residual , Reoperación , Estudios Retrospectivos , Factores de Riesgo , Tasa de Supervivencia , Espera Vigilante
17.
BMC Cancer ; 17(1): 282, 2017 04 19.
Artículo en Inglés | MEDLINE | ID: mdl-28424071

RESUMEN

BACKGROUND: The identification of four Consensus Molecular Subtypes (CMS1-4) of colorectal cancer forms a new paradigm for the design and evaluation of subtype-directed therapeutic strategies. The most aggressive subtype - CMS4 - has the highest chance of disease recurrence. Novel adjuvant therapies for patients with CMS4 tumours are therefore urgently needed. CMS4 tumours are characterized by expression of mesenchymal and stem-like genes. Previous pre-clinical work has shown that targeting Platelet-Derived Growth Factor Receptors (PDGFRs) and the related KIT receptor with imatinib is potentially effective against mesenchymal-type colon cancer. In the present study we aim to provide proof for the concept that imatinib can reduce the aggressive phenotype of primary CMS4 colon cancer. METHODS: Tumour biopsies from patients with newly diagnosed stage I-III colon cancer will be analysed with a novel RT-qPCR test to pre-select patients with CMS4 tumours. Selected patients (n = 27) will receive treatment with imatinib (400 mg per day) starting two weeks prior to planned tumour resection. To assess treatment-induced changes in the aggressive CMS4 phenotype, RNA sequencing will be performed on pre- and post-treatment tissue samples. DISCUSSION: The development of effective adjuvant therapy for primary colon cancer is hindered by multiple factors. First, new drugs that may have value in the prevention of (early) distant recurrence are almost always first tested in patients with heavily pre-treated metastatic disease. Second, measuring on-target drug effects and biological consequences in tumour tissue is not commonly a part of the study design. Third, due to the lack of patient selection tools, clinical trials in the adjuvant setting require large patient populations. Finally, the evaluation of recurrence-prevention requires a long-term follow-up. In the ImPACCT trial these issues are addressed by including newly diagnosed pre-selected patients with CMS4 tumours prior to primary tumour resection, rather than non-selected patients with late-stage disease. By making use of the pre-operative window period, the biological effect of imatinib treatment on CMS4 tumours can be rapidly assessed. Delivering proof-of-concept for drug action in early stage disease should form the basis for the design of future trials with subtype-targeted therapies in colon cancer patients. TRIAL REGISTRATION: ClinicalTrials.gov: NCT02685046 . Registration date: February 9, 2016.


Asunto(s)
Antineoplásicos/uso terapéutico , Neoplasias Colorrectales/tratamiento farmacológico , Mesilato de Imatinib/uso terapéutico , Quimioterapia Adyuvante , Ensayos Clínicos Fase II como Asunto , Neoplasias Colorrectales/patología , Humanos , Estudios Multicéntricos como Asunto , Periodo Preoperatorio , Pronóstico , Proyectos de Investigación , Resultado del Tratamiento
18.
Br J Dermatol ; 176(5): 1345-1350, 2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-27534273

RESUMEN

The inherited palmoplantar keratodermas (PPKs) are a heterogeneous group of genodermatoses, characterized by thickening of the epidermis of the palms and soles. No classification system satisfactorily unites clinical presentation, pathology and molecular pathogenesis. There are four patterns of hyperkeratosis - striate, focal, diffuse and punctate. Mutations in the desmoglein 1 gene (DSG1), a transmembrane glycoprotein, have been reported primarily in striate, but also in focal and diffuse PPKs. We report seven unrelated pedigrees with dominantly inherited PPK owing to mutations in the DSG1 gene, with marked phenotypic variation. Genomic DNA from each family was isolated, and individual exons amplified by polymerase chain reaction. Sanger sequencing was employed to identify mutations. Mutation analysis identified novel mutations in five families (p.Tyr126Hisfs*2, p.Ser521Tyrfs*2, p.Trp3*, p.Asp591Phefs*9 and p.Met249Ilefs*6) with striate palmar involvement and varying focal or diffuse plantar disease, and the recurrent mutation c.76C>T, p.Arg26*, in two families with variable PPK patterns. We report one recurrent and five novel DSG1 mutations, causing varying patterns of PPK, highlighting the clinical heterogeneity arising from mutations in this gene.


Asunto(s)
Desmogleína 1/genética , Queratodermia Palmoplantar/genética , Mutación/genética , África/etnología , Américas/etnología , Europa (Continente)/etnología , Femenino , Pruebas Genéticas , Humanos , Masculino , Linaje , Fenotipo , Adulto Joven
19.
Phys Rev Lett ; 116(24): 240503, 2016 Jun 17.
Artículo en Inglés | MEDLINE | ID: mdl-27367372

RESUMEN

Bath engineering, which utilizes coupling to lossy modes in a quantum system to generate nontrivial steady states, is a tantalizing alternative to gate- and measurement-based quantum science. Here, we demonstrate dissipative stabilization of entanglement between two superconducting transmon qubits in a symmetry-selective manner. We utilize the engineered symmetries of the dissipative environment to stabilize a target Bell state; we further demonstrate suppression of the Bell state of opposite symmetry due to parity selection rules. This implementation is resource efficient, achieves a steady-state fidelity F=0.70, and is scalable to multiple qubits.

20.
BMC Gastroenterol ; 16(1): 56, 2016 May 26.
Artículo en Inglés | MEDLINE | ID: mdl-27229709

RESUMEN

BACKGROUND: Endoscopic mucosal resection (EMR) is currently the most used technique for resection of large distal colorectal polyps. However, in large lesions EMR can often only be performed in a piecemeal fashion resulting in relatively low radical (R0)-resection rates and high recurrence rates. Endoscopic submucosal dissection (ESD) is a newer procedure that is more difficult resulting in a longer procedural time, but is promising due to the high en-bloc resection rates and the very low recurrence rates. We aim to evaluate the (cost-)effectiveness of ESD against EMR on both short (i.e. 6 months) and long-term (i.e. 36 months). We hypothesize that in the short-run ESD is more time consuming resulting in higher healthcare costs, but is (cost-) effective on the long-term due to lower patients burden, a higher number of R0-resections and lower recurrence rates with less need for repeated procedures. METHODS: This is a multicenter randomized clinical trial in patients with a non-pedunculated polyp larger than 20 mm in the rectum, sigmoid, or descending colon suspected to be an adenoma by means of endoscopic assessment. Primary endpoint is recurrence rate at follow-up colonoscopy at 6 months. Secondary endpoints are R0-resection rate, perceived burden and quality of life, healthcare resources utilization and costs, surgical referral rate, complication rate and recurrence rate at 36 months. Quality-adjusted-life-year (QALY) will be estimated taking an area under the curve approach and using EQ-5D-indexes. Healthcare costs will be calculated by multiplying used healthcare services with unit prices. The cost-effectiveness of ESD against EMR will be expressed as incremental cost-effectiveness ratios (ICER) showing additional costs per recurrence free patient and as ICER showing additional costs per QALY. DISCUSSION: If this trial confirms ESD to be favorable on the long-term, the burden of extra colonoscopies and repeated procedures can be prevented for future patients. TRIAL REGISTRATION: NCT02657044 (Clinicaltrials.gov), registered January 8, 2016.


Asunto(s)
Adenoma/cirugía , Neoplasias Colorrectales/cirugía , Resección Endoscópica de la Mucosa/economía , Resección Endoscópica de la Mucosa/métodos , Adenoma/patología , Colonoscopía , Neoplasias Colorrectales/patología , Costo de Enfermedad , Análisis Costo-Beneficio , Resección Endoscópica de la Mucosa/efectos adversos , Costos de la Atención en Salud , Humanos , Recurrencia Local de Neoplasia , Calidad de Vida
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