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1.
Nature ; 598(7879): 49-52, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34616055

RESUMEN

Spacecraft missions have observed regolith blankets of unconsolidated subcentimetre particles on stony asteroids1-3. Telescopic data have suggested the presence of regolith blankets also on carbonaceous asteroids, including (101955) Bennu4 and (162173) Ryugu5. However, despite observations of processes that are capable of comminuting boulders into unconsolidated materials, such as meteoroid bombardment6,7 and thermal cracking8, Bennu and Ryugu lack extensive areas covered in subcentimetre particles7,9. Here we report an inverse correlation between the local abundance of subcentimetre particles and the porosity of rocks on Bennu. We interpret this finding to mean that accumulation of unconsolidated subcentimetre particles is frustrated where the rocks are highly porous, which appears to be most of the surface10. The highly porous rocks are compressed rather than fragmented by meteoroid impacts, consistent with laboratory experiments11,12, and thermal cracking proceeds more slowly than in denser rocks. We infer that regolith blankets are uncommon on carbonaceous asteroids, which are the most numerous type of asteroid13. By contrast, these terrains should be common on stony asteroids, which have less porous rocks and are the second-most populous group by composition13. The higher porosity of carbonaceous asteroid materials may have aided in their compaction and cementation to form breccias, which dominate the carbonaceous chondrite meteorites14.

2.
Exp Parasitol ; 260: 108744, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38513971

RESUMEN

Suramin was the first effective drug for the treatment of human African sleeping sickness. Structural analogues of the trypanocide have previously been shown to be potent inhibitors of several enzymes. Therefore, four suramin analogues lacking the methyl group on the intermediate rings and with different regiochemistry of the naphthalenetrisulphonic acid groups and the phenyl rings were tested to establish whether they exhibited improved antiproliferative activity against bloodstream forms of Trypanosomes brucei compared to the parent compound. The four analogues exhibited low trypanocidal activity and weak inhibition of the antitrypanosomal activity of suramin in competition experiments. This indicates that the strong trypanocidal activity of suramin is most likely due to the presence of methyl groups on its intermediate rings and to the specific regiochemistry of naphthalenetrisulphonic acid groups. These two structural features are also likely to be important for the inhibition mechanism of suramin because DNA distribution and nucleus/kinetoplast configuration analyses suggest that the analogues inhibit mitosis while suramin inhibits cytokinesis.


Asunto(s)
Suramina , Tripanocidas , Trypanosoma brucei brucei , Suramina/farmacología , Suramina/química , Tripanocidas/farmacología , Tripanocidas/química , Trypanosoma brucei brucei/efectos de los fármacos , Animales , Relación Estructura-Actividad , ADN Protozoario/efectos de los fármacos , ADN de Cinetoplasto/efectos de los fármacos , Ratones , Mitosis/efectos de los fármacos , Tripanosomiasis Africana/tratamiento farmacológico , Tripanosomiasis Africana/parasitología
3.
Bioorg Med Chem ; 92: 117424, 2023 09 07.
Artículo en Inglés | MEDLINE | ID: mdl-37517101

RESUMEN

Osteoarthritis is a chronic degenerative joint disease affecting millions of people worldwide, with no disease-modifying drugs currently available to treat the disease. Tissue inhibitor of metalloproteinases 3 (TIMP-3) is a potential therapeutic target in osteoarthritis because of its ability to inhibit the catabolic metalloproteinases that drive joint damage by degrading the cartilage extracellular matrix. We previously found that suramin inhibits cartilage degradation through its ability to block endocytosis and intracellular degradation of TIMP-3 by low-density lipoprotein receptor-related protein 1 (LRP1), and analysis of commercially available suramin analogues indicated the importance of the 1,3,5-trisulfonic acid substitutions on the terminal naphthalene rings for this activity. Here we describe synthesis and structure-activity relationship analysis of additional suramin analogues using ex vivo models of TIMP-3 trafficking and cartilage degradation. This showed that 1,3,6-trisulfonic acid substitution of the terminal naphthalene rings was also effective, and that the protective activity of suramin analogues depended on the presence of a rigid phenyl-containing central region, with para/para substitution of these phenyl rings being most favourable. Truncated analogues lost protective activity. The physicochemical characteristics of suramin and its analogues indicate that approaches such as intra-articular injection would be required to develop them for therapeutic use.


Asunto(s)
Osteoartritis , Inhibidor Tisular de Metaloproteinasa-3 , Humanos , Inhibidor Tisular de Metaloproteinasa-3/metabolismo , Inhibidor Tisular de Metaloproteinasa-3/farmacología , Inhibidor Tisular de Metaloproteinasa-3/uso terapéutico , Suramina/farmacología , Suramina/metabolismo , Suramina/uso terapéutico , Cartílago/metabolismo , Osteoartritis/tratamiento farmacológico , Osteoartritis/metabolismo , Metaloproteasas/metabolismo , Metaloproteasas/farmacología , Metaloproteasas/uso terapéutico
4.
Am J Physiol Gastrointest Liver Physiol ; 322(5): G500-G512, 2022 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-35170365

RESUMEN

We used in silico models to investigate the impact of the dimensions of myotomy, contraction pattern, the tone of the esophagogastric junction (EGJ), and musculature at the myotomy site on esophageal wall stresses potentially leading to the formation of a blown-out myotomy (BOM). We performed three sets of simulations with an in silico esophagus model, wherein the myotomy-influenced region was modeled as an elliptical section devoid of muscle fibers. These sets investigated the effects of the dimensions of myotomy, differing esophageal contraction types, and differing esophagogastric junction (EGJ) tone and wall stiffness at the myotomy affected region on esophageal wall stresses potentially leading to BOM. Longer myotomy was found to be accompanied by a higher bolus volume accumulated at the myotomy site. With respect to esophageal contractions, deformation at the myotomy site was greatest with propagated peristalsis, followed by combined peristalsis and spasm, and pan-esophageal pressurization. Stronger EGJ tone with respect to the wall stiffness at the myotomy site was found to aid in increasing deformation at the myotomy site. In addition, we found that an esophagus with a shorter myotomy performed better at emptying the bolus than that with a longer myotomy. Shorter myotomies decrease the chance of BOM formation. Propagated peristalsis with EGJ outflow obstruction has the highest chance of BOM formation. We also found that abnormal residual EGJ tone may be a co-factor in the development of BOM, whereas remnant muscle fibers at myotomy site reduce the risk of BOM formation.NEW & NOTEWORTHY Blown-out myotomy (BOM) is a complication observed after myotomy, which is performed to treat achalasia. In silico simulations were performed to identify the factors leading to BOM formation. We found that a short myotomy that is not transmural and has some structural architecture intact reduces the risk of BOM formation. In addition, we found that high esophagogastric junction tone due to fundoplication is found to increase the risk of BOM formation.


Asunto(s)
Acalasia del Esófago , Miotomía , Acalasia del Esófago/cirugía , Unión Esofagogástrica , Fundoplicación , Humanos , Manometría , Resultado del Tratamiento
5.
Ann Surg ; 273(6): 1135-1140, 2021 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-33914488

RESUMEN

OBJECTIVE: We aim to describe the long-term follow-up data from our institution's POEM experience. SUMMARY BACKGROUND DATA: Per-oral endoscopic myotomy (POEM) is a well-established endoscopic therapy for achalasia with excellent short-term efficacy, but long-term outcomes data are limited. METHODS: Patients older than 4 years removed from POEM for treatment of achalasia were studied. Clinical success was defined as an Eckardt Symptom (ES) score ≤3 and freedom from reintervention for achalasia. Patients underwent esophagogastroduodenoscopy (EGD), high-resolution manometry, impedance planimetry, and timed barium esophagram (TBE) preoperatively and at least 4 years postoperatively. Objective gastroesophageal reflux disease (GERD) was defined LA Grade B or worse esophagitis on EGD. RESULTS: One hundred and nineteen consecutive patients were included. Five patients died or had catastrophic events unrelated to achalasia or POEM. One hundred of the remaining patients (88%, 100/114) had long-term data available. Clinical follow-up for all patients was greater than 4 years postoperatively and the mean was 55 months. Mean current ES was significantly improved from preop (n = 100, 1 ±â€Š1 vs 7 ±â€Š2, P < 0.001). Overall clinical success was 88% and 92%. Five patients had a current ES >3 and 4 patients required procedural reintervention on the lower esophageal sphincter. Reinterventions were successful in 75% of patients (3/4), with current ES ≤3. The rate of objective GERD was 33% (15/45). Esophageal physiology was improved with a decrease in median integrated relaxation pressure (11 ±â€Š4 vs 33 ±â€Š15 mm Hg, P < 0.001), a decrease in median TBE column height (3 ±â€Š3 vs 13 ±â€Š8 cm, P < 0.001), and an increase in median distensibility index (5.1 ±â€Š2 vs 1.1 ±â€Š1 mm2/mm Hg, P < 0.001). CONCLUSIONS: POEM provides durable symptom relief and improvement in physiologic esophagogastric junction relaxation parameters over 4.5 years postoperatively. Reinterventions are rare and effective.


Asunto(s)
Acalasia del Esófago/cirugía , Piloromiotomia , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Factores de Tiempo , Resultado del Tratamiento
6.
Br J Dermatol ; 2021 Aug 19.
Artículo en Inglés | MEDLINE | ID: mdl-34411292

RESUMEN

BACKGROUND: Palmoplantar pustulosis (PPP) is a rare, debilitating, chronic inflammatory skin disease that affects the hands and feet. Clinical, immunological and genetic findings suggest a pathogenic role for interleukin (IL)-1. OBJECTIVES: To determine whether anakinra (an IL-1 receptor antagonist) delivers therapeutic benefit in PPP. METHODS: This was a randomized (1 : 1), double-blind, two-staged, adaptive, UK multicentre, placebo-controlled trial [ISCRTN13127147 (registered 1 August 2016); EudraCT number: 2015-003600-23 (registered 1 April 2016)]. Participants had a diagnosis of PPP (> 6 months) requiring systemic therapy. Treatment was 8 weeks of anakinra or placebo via daily, self-administered subcutaneous injections. Primary outcome was the Palmoplantar Pustulosis Psoriasis Area and Severity Index (PPPASI) at 8 weeks. RESULTS: A total of 374 patients were screened; 64 were enrolled (31 in the anakinra arm and 33 in the placebo arm) with a mean (SD) baseline PPPASI of 17·8 (10·5) and a PPP investigator's global assessment of severe (50%) or moderate (50%). The baseline adjusted mean difference in PPPASI favoured anakinra but did not demonstrate superiority in the intention-to-treat analysis [-1·65, 95% confidence interval (CI) -4·77 to 1·47; P = 0·30]. Similarly, secondary objective measures, including fresh pustule count (2·94, 95% CI -26·44 to 32·33; favouring anakinra), total pustule count (-30·08, 95% CI -83·20 to 23·05; favouring placebo) and patient-reported outcomes, did not show superiority of anakinra. When modelling the impact of adherence, the PPPASI complier average causal effect for an individual who received ≥ 90% of the total treatment (48% in the anakinra group) was -3·80 (95% CI -10·76 to 3·16; P = 0·285). No serious adverse events occurred. CONCLUSIONS: No evidence for the superiority of anakinra was found. IL-1 blockade is not a useful intervention for the treatment of PPP.

7.
Gastrointest Endosc ; 93(4): 861-868.e1, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-32721488

RESUMEN

BACKGROUND AND AIMS: Although laparoscopic Heller myotomy (LHM) or peroral endoscopic myotomy (POEM) is highly effective, 10% to 20% of patients with achalasia remain symptomatic after treatment. In evaluating such patients, we have observed a pattern of failure associated with a pseudodiverticulum, or blown-out myotomy (BOM), in the distal esophagus. We aimed to assess risk factors and patient-reported outcomes associated with a BOM. METHODS: We reviewed our manometry database for patients with achalasia previously treated with LHM or POEM. We included patients who had a post-treatment esophagram within 1 year of their follow-up manometry. A BOM was defined radiographically as a wide-mouthed outpouching (>50% increase in esophageal diameter) in the area of the myotomy. RESULTS: One hundred twenty-nine patients with achalasia who underwent treatment were included; 23 (17.8%) had a BOM. Comparing patients with a BOM with those without, post-treatment Eckardt scores were significantly greater (5 vs 2, P = .002), type III achalasia was more common (39.1% vs 14.2%, P = .005), and LHM was more common than POEM (73.9% vs 26.1%, P = .013). The integrated relaxation pressure was also significantly greater in the BOM group (15.0 mm Hg vs 11.0 mm Hg, P = .025). CONCLUSIONS: BOM is a common adverse event after myotomy for achalasia but is not seen after pneumatic dilation. Pretreatment type III achalasia, LHM as opposed to POEM, and a greater post-treatment integrated relaxation pressure were risk factors for developing a BOM. We speculate that esophageal wall strain in the area weakened by myotomy, whether from residual spastic contractility or continued esophageal outflow obstruction, may be the underlying mechanism of BOM development.


Asunto(s)
Acalasia del Esófago , Miotomía de Heller , Laparoscopía , Miotomía , Cirugía Endoscópica por Orificios Naturales , Acalasia del Esófago/cirugía , Esfínter Esofágico Inferior/cirugía , Miotomía de Heller/efectos adversos , Humanos , Cirugía Endoscópica por Orificios Naturales/efectos adversos , Resultado del Tratamiento
8.
Surg Endosc ; 35(9): 5140-5146, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-33025249

RESUMEN

BACKGROUND: Laparoscopic common bile duct exploration (LCBDE) is an underutilized therapy for choledocholithiasis. The driving factors of this practice gap are poorly defined. We sought to evaluate the attitudes and practice patterns of surgeons who underwent training courses using an LCBDE simulator. METHODS: Surgeons completed a half-day simulator-based LCBDE curriculum at national courses, including the American College of Surgeons Advanced Skills Training for Rural Surgeons and the Society of American Gastrointestinal and Endoscopic Surgeons annual meeting. Attitudes were assessed with Likert surveys immediately before and after curriculum completion. Follow-up surveys were distributed electronically. RESULTS: 159 surgeons completed training during six courses. Surgeon attitudes regarding the overall superiority of LCBDE vs. ERCP shifted towards favoring LCBDE after course participation (4.0 vs 3.3; Likert scale 1-5, p < 0.001). 44% of surgeons completed follow-up surveys at a mean of 3 years post-course. Surgeons remained confident in their ability to perform LCBDE, with only 14% rating their skill as a significant barrier to practice, as compared with 43% prior to course participation (p < 0.01). However, only 28% of surgeons saw an increase in LCBDE volume. Deficiencies in operating room (OR) staff knowledge and instrument availability were the most significant barriers to post-course practice implementation and were inversely correlated with LCBDE case volume (ρ = - 0.44 and - 0.47, both p < 0.01). Surgeons for whom OR staff knowledge of LCBDE was not a significant barrier performed nearly 4 times more LCBDE than those who rated staff knowledge as a moderate, strong, or complete barrier. CONCLUSIONS: Surgeons trained at an LCBDE course retained long-term confidence in their procedural ability. Practice implementation was hindered by deficiencies in OR staff knowledge and instrument availability. Surgeons with knowledgeable operating room staff performed significantly more LCBDEs than those with less capable assistance. These barriers should be addressed in future curricula to improve procedural adoption.


Asunto(s)
Colecistectomía Laparoscópica , Coledocolitiasis , Laparoscopía , Cirujanos , Colangiopancreatografia Retrógrada Endoscópica , Coledocolitiasis/cirugía , Conducto Colédoco/diagnóstico por imagen , Conducto Colédoco/cirugía , Curriculum , Humanos , Estudios Retrospectivos
9.
Surg Endosc ; 35(6): 3090-3096, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-32632483

RESUMEN

BACKGROUND: Esophagogastric junction distensibility index (DI), measured using the functional luminal imaging probe (FLIP), correlates with symptomatic outcomes after interventions for achalasia. The objective of this study was to determine if the intraoperative measurement of DI using FLIP was associated with improved clinical outcomes following per-oral endoscopic myotomy (POEM) for achalasia when compared with procedures in which FLIP was not utilized. METHODS: Patients undergoing POEM from 2012 to 2017 at a single institution by a single surgeon were studied. Use of FLIP during this time period was based on catheter and technician availability, resulting in two patient cohorts. In patients in whom FLIP was used, operative video recordings were reviewed to determine when DI measurements led to the performance of additional myotomy. Postoperative Eckardt symptom scores (ES) at 12 months and postoperative physiologic studies were compared between patients with and without intraoperative FLIP. Associations were assessed using Mann-Whitney U and Chi-square tests. RESULTS: 143 patients were included in the analysis (61 with intraoperative FLIP and 82 without FLIP). Video recordings were available for 85% of the FLIP cohort. Review of these operative recordings revealed that 65% of patients who underwent FLIP had additional myotomy performed following the initial postmyotomy FLIP measurement. At 12 months after POEM, the FLIP cohort had significantly more clinical successes (defined as ES ≤ 3) than patients in whom FLIP was not used (93% vs. 81%, p < 0.05). CONCLUSIONS: Use of intraoperative FLIP during POEM resulted in the surgeon performing additional myotomy in over half of cases and was associated with improved clinical outcomes. This study demonstrates the potential for a FLIP-tailored myotomy to improve outcomes in patients undergoing surgical myotomy for achalasia.


Asunto(s)
Acalasia del Esófago , Miotomía , Cirugía Endoscópica por Orificios Naturales , Diagnóstico por Imagen , Pruebas Diagnósticas de Rutina , Acalasia del Esófago/cirugía , Esfínter Esofágico Inferior , Unión Esofagogástrica , Humanos , Resultado del Tratamiento
10.
Surg Endosc ; 35(6): 3097-3103, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-32601759

RESUMEN

BACKGROUND: The functional luminal imaging probe (FLIP) can be used to measure the esophagogastric junction distensibility index (DI) during myotomy for achalasia and increased DI has been shown to predict superior clinical outcomes. The objective of this study was to determine if the intraoperative DI and the changes produced by per oral endoscopic myotomy (POEM) differed between achalasia subtypes. METHODS: FLIP measurements were performed during POEM for achalasia at a single institution. DI (defined as the minimum cross-sectional area (CSA) at the EGJ divided by distensive pressure) was measured at three time points: after induction of anesthesia, after submucosal tunneling, and after myotomy. Measurements were reported at the 40 mL fill volume for the 8 cm FLIP (EF-325) and at the 60 mL fill volume for the 16 cm FLIP (EF-322). Measurements were compared using chi-square and Kruskal-Wallis tests. RESULTS: 142 patients had intraoperative FLIP performed during POEM for achalasia between 2012 and 2019 (30 type I, 68 type II, 27 type III, and 17 variant). Patients with type I achalasia had a significantly higher induction DI (median 1.7 mm2/mmHg) than type II (0.8 mm2/mmHg), type III (0.9 mm2/mmHg), and variants (1.1 mm2/mmHg; p < 0.001). These differences persisted after submucosal tunneling and final DI after myotomy was also significantly higher in type I patients (median 8.0 mm2/mmHg) compared to type II (5.8 mm2/mmHg), type III (3.9 mm2/mmHg), and variants (5.4 mm2/mmHg; p < 0.001). Achalasia subtypes were found to have similar CSA at all time points, whereas pressure differed with type I having the lowest pressure and type III the highest. CONCLUSION: The DI at each operative step during POEM was found to differ significantly between achalasia subtypes. These differences in DI were due to pressure, as CSA was similar between subtypes. Achalasia subtype should be accounted for when using FLIP as an intraoperative calibration tool and in future studies examining the relationship between DI and clinical outcomes.


Asunto(s)
Procedimientos Quirúrgicos del Sistema Digestivo , Acalasia del Esófago , Miotomía , Cirugía Endoscópica por Orificios Naturales , Diagnóstico por Imagen , Acalasia del Esófago/diagnóstico por imagen , Acalasia del Esófago/cirugía , Unión Esofagogástrica/diagnóstico por imagen , Unión Esofagogástrica/cirugía , Esofagoscopía , Humanos , Resultado del Tratamiento
11.
Surg Endosc ; 34(6): 2593-2600, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-31376012

RESUMEN

BACKGROUND: The functional luminal imaging probe (FLIP) can evaluate esophagogastric junction (EGJ) distensibility and esophageal peristalsis in real time. FLIP measurements performed during diagnostic endoscopy can accurately discriminate between healthy controls and patients with achalasia based on EGJ-distensibility and distinct motility patterns termed repetitive antegrade contractions (RACs) and repetitive retrograde contractions (RRCs). We sought to evaluate real-time motility changes in patients undergoing surgical myotomy for achalasia. METHODS: FLIP measurements using a stepwise volumetric distention protocol were performed at three time points during assessment and performance of laparoscopic Heller myotomy and POEM: (1) During preoperative outpatient endoscopy, (2) Intraoperatively following induction of anesthesia, and (3) Intraoperatively after myotomy completion. EGJ-distensibility, contractility, RACs, and RRCs were measured. RESULTS: FLIP measurements were performed in 32 patients. The EGJ-distensibility index was similar between the preoperative and initial operative measurements (1.1 vs 1.4 mm2/mmHg, p = NS). There was a significant increase in distensibility following surgical myotomy (1.4 to 4.7 mm2/mmHg, p < 0.01). Intraoperative contractile patterns varied between achalasia subtypes. Contractility was seen in < 20% of assessments in patients with types I and II achalasia. Type III patients demonstrated contractility in 100% of assessments, with 70% exhibiting RRCs and 60% RACs. There was a reduction in the frequency of RRC presence (70% to 20%), and contractile vigor (80% to 0% of patients with lumen occluding contractions) in type III patients following surgical myotomy. CONCLUSIONS: This first report of real-time intraoperative measurement of esophageal motility using FLIP demonstrates the feasibility of such assessments during surgical myotomy for achalasia. Patients with type I and II achalasia exhibited rare intraoperative contractility, while the presence of motility was the norm in those with type III. Patients with type III achalasia demonstrated an immediate reduction in repetitive contraction motility patterns and contractile vigor following myotomy.


Asunto(s)
Acalasia del Esófago/cirugía , Esófago/fisiología , Miotomía/métodos , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Periodo Intraoperatorio , Masculino , Persona de Mediana Edad , Adulto Joven
12.
Tech Gastrointest Endosc ; 20(3): 114-119, 2018 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-30872910

RESUMEN

Achalasia is a rare esophageal motility disorder that necessitates the disruption of the lower esophageal sphincter. Patients with achalasia should be evaluated in a systematic, multidisciplinary fashion. Workup should include upper endoscopy, esophagography, and high-resolution manometry. The gold standard for surgical treatment is laparoscopic Heller myotomy with partial fundoplication. Per-oral esophageal myotomy is a novel endoscopic technique that has gained considerable traction over the past decade. The procedure includes the creation of a submucosal tunnel and a selective circular myotomy of the lower esophageal sphincter. Common intra-operative hazards include bleeding within the submucosal tunnel and capnoperitoneum. Significant complications are rare. Patients experience excellent dysphagia relief that is on par with laparoscopic Heller myotomy at moderate-term follow up. Post-operative gastroesophageal reflux disease occurs in greater than one-third of patients, and the vast majority of cases are readily controlled with an anti-secretory medication. Although data is sparse, there is a growing body of literature that supports the long-term durability of per-oral esophageal myotomy.

13.
Ann Oncol ; 25(10): 1941-1948, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-25057173

RESUMEN

BACKGROUND: ZODIAC was a randomized phase III study of second-line treatment in patients with advanced non-small cell lung cancer (NSCLC) that evaluated the addition of vandetanib to docetaxel. The study showed a statistically significant improvement in progression-free survival and objective response rate, but not in overall survival for unselected patients. This study evaluated epidermal growth factor receptor (EGFR) gene mutation, copy number gain, and protein expression, and KRAS gene mutation, in pretreatment tumor samples as potential biomarkers predicting benefit from vandetanib as second-line treatment of NSCLC. PATIENTS AND METHODS: After progression following first-line chemotherapy, 1391 patients with locally advanced or metastatic (stage IIIB/IV) NSCLC were randomized 1 : 1 to receive vandetanib (100 mg/day) plus docetaxel (75 mg/m(2) every 21 days) or placebo plus docetaxel in the ZODIAC study. Archival tumor samples (n = 570) were collected from consenting patients (n = 958) for predefined, prospective biomarker analyses. RESULTS: Of evaluable samples, 14% were EGFR mutation positive, 35% were EGFR FISH positive, 88% were EGFR protein expression positive, and 13% were KRAS mutation positive. Compared with the overall study population, in which progression-free survival (PFS) [hazard ratio (HR) = 0.79] but not OS (HR = 0.91) were significantly improved with vandetanib, there was greater relative clinical benefit for patients with EGFR mutation-positive tumors [PFS HR 0.51, confidence interval (CI) 0.25-1.06 and OS HR 0.46, CI 0.14-1.57] and EGFR FISH-positive tumors (PFS HR 0.61, CI 0.39-0.94 and OS HR 0.48, CI 0.28-0.84). Similarly, patients with EGFR mutation or FISH-positive tumor samples who received vandetanib had an increased chance of objective tumor response (odds ratios 3.34, CI 0.8-13.89, and 3.90, CI 1.02-14.82, respectively). There did not appear to be benefit for vandetanib in patients with KRAS mutation-positive tumors. CONCLUSIONS: High EGFR gene copy number or activating EGFR mutations may identify patient subgroups who receive increased clinical benefit from vandetanib in combination with docetaxel in second-line NSCLC. CLINICALTRIALSGOV: NCT00312377.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/genética , Receptores ErbB/genética , Piperidinas/administración & dosificación , Quinazolinas/administración & dosificación , Taxoides/administración & dosificación , Protocolos de Quimioterapia Combinada Antineoplásica , Biomarcadores de Tumor/genética , Carcinoma de Pulmón de Células no Pequeñas/patología , Supervivencia sin Enfermedad , Docetaxel , Femenino , Dosificación de Gen , Humanos , Masculino , Mutación , Pronóstico , Proteínas Proto-Oncogénicas/genética , Proteínas Proto-Oncogénicas p21(ras) , Proteínas ras/genética
14.
Br J Cancer ; 106(12): 1960-6, 2012 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-22596237

RESUMEN

BACKGROUND: Non-invasive quantitative imaging biomarkers are essential for the evaluation of novel targeted therapeutics. Before deployment in clinical trials, such imaging biomarkers require qualification, typically through pre-clinical identification of imaging-pathology correlates. METHODS: First, in investigating imaging biomarkers of invasion, the response of orthotopic murine PC3 prostate xenografts to the Src inhibitor saracatinib was assessed using susceptibility contrast MRI. Second, the longitudinal response of chemically induced rat mammary adenocarcinomas to the VEGFR2 inhibitor vandetanib was monitored by intrinsic susceptibility MRI, to identify the time window of transient vascular normalisation. RESULTS: No significant differences in fractional blood volume (%), vessel calibre (µm), native T(1) (ms) or apparent water diffusion coefficient were determined, despite reduced expression of activated Fak and paxillin in the saracatinib cohort. Treatment with vandetanib elicited a 60% antitumour response (P<0.01), 80% inhibition in vessel density (P<0.05) and reduction in hypoxia (P<0.05). There was, however, no significant change in tumour baseline R(2)* (s(-1)) or carbogen-induced ΔR(2)* with treatment. CONCLUSION: Reporting negative imaging biomarker responses is important, to avoid the risk of clinical trials using the same biomarkers being undertaken with a false expectation of success, and the abandonment of promising new therapeutics based on a false-negative imaging biomarker response being mistaken for a true-negative.


Asunto(s)
Benzodioxoles/uso terapéutico , Vasos Sanguíneos/patología , Imagen por Resonancia Magnética/métodos , Neoplasias Mamarias Experimentales/tratamiento farmacológico , Piperidinas/uso terapéutico , Neoplasias de la Próstata/tratamiento farmacológico , Proteínas Proto-Oncogénicas pp60(c-src)/antagonistas & inhibidores , Quinazolinas/uso terapéutico , Receptor 2 de Factores de Crecimiento Endotelial Vascular/antagonistas & inhibidores , Animales , Biomarcadores de Tumor , Vasos Sanguíneos/efectos de los fármacos , Hipoxia de la Célula/efectos de los fármacos , Línea Celular Tumoral , Reacciones Falso Negativas , Femenino , Humanos , Masculino , Neoplasias Mamarias Experimentales/inducido químicamente , Neoplasias Mamarias Experimentales/patología , Ratones , Terapia Molecular Dirigida , Trasplante de Neoplasias , Neoplasias de la Próstata/diagnóstico , Neoplasias de la Próstata/patología , Ratas
15.
Science ; 377(6603): 285-291, 2022 07 15.
Artículo en Inglés | MEDLINE | ID: mdl-35857591

RESUMEN

Carbonaceous asteroids, such as (101955) Bennu, preserve material from the early Solar System, including volatile compounds and organic molecules. We report spacecraft imaging and spectral data collected during and after retrieval of a sample from Bennu's surface. The sampling event mobilized rocks and dust into a debris plume, excavating a 9-meter-long elliptical crater. This exposed material is darker, spectrally redder, and more abundant in fine particulates than the original surface. The bulk density of the displaced subsurface material was 500 to 700 kilograms per cubic meter, which is about half that of the whole asteroid. Particulates that landed on instrument optics spectrally resemble aqueously altered carbonaceous meteorites. The spacecraft stored 250 ± 101 grams of material, which will be delivered to Earth in 2023.

16.
Br J Dermatol ; 165(5): 1124-6, 2011 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-21711328

RESUMEN

BACKGROUND: Dermatological teaching has traditionally stressed that complete skin examination is essential in the assessment of patients with potential skin disease. OBJECTIVES: To determine whether complete skin examination results in increased diagnoses of skin malignancies that would not have been discovered otherwise. METHODS: New patients (n = 483) attending a dermatology clinic in a university teaching hospital and private dermatology practice had a complete skin examination, as is our normal practice. These patients were seen over a 9-month period (January-September 2009). All patients were examined by the same consultant dermatologist. Data were collected on patients' sex, age, presenting complaint and findings on complete skin examination. RESULTS: Two nodular malignant melanomas with mean Breslow thickness of 0·6 mm (0·4%) and one melanoma in situ were identified at sites distant from the patient's presenting complaint. Sixteen patients (3·3%) had a basal cell carcinoma that would not have been discovered if the presenting lesion alone had been examined. Thirty-three patients (6·8%) had actinic keratoses or squamous cell carcinoma in situ and nine (1·9%) had dysplastic naevi. A further 21 patients (4·3%) had a suspicious lesion biopsied or excised with subsequent benign histology. Seventy-three patients (15·1%) had other benign dermatological diagnoses requiring treatment or investigation. CONCLUSIONS: In a 9-month period, in a sample of 483 new patients, three patients (0·6%) had potentially lethal skin malignancies identified that would not have been diagnosed without a complete skin examination. Sixteen (3·3%) patients had basal cell carcinomas that would have been missed without complete skin examination. This study confirms the traditional teaching that complete skin examination has the potential to reduce morbidity and mortality from cutaneous malignancy.


Asunto(s)
Examen Físico/métodos , Neoplasias Cutáneas/diagnóstico , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Detección Precoz del Cáncer , Femenino , Humanos , Masculino , Persona de Mediana Edad , Adulto Joven
18.
ESMO Open ; 6(2): 100079, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33721621

RESUMEN

BACKGROUND: Preclinical studies suggest that combining vandetanib (VAN), a multi-tyrosine kinase inhibitor of rearranged during transfection (RET) proto-oncogene, vascular endothelial growth factor receptor (VEGFR), and epidermal growth factor receptor (EGFR), with everolimus (EV), a mammalian target of rapamycin (mTOR) inhibitor, may improve antitumor activity. We determined the safety, maximum tolerated dose (MTD), recommended phase II dose (RP2D), and dose-limiting toxicities (DLTs) of VAN + EV in patients with advanced solid cancers and the effect of combination therapy on cancer cell proliferation and intracellular pathways. PATIENTS AND METHODS: Patients with refractory solid tumors were enrolled in a phase I dose-escalation trial testing VAN (100-300 mg orally daily) + EV (2.5-10 mg orally daily). Objective responses were evaluated using RECIST v1.1. RET mutant cancer cell lines were used in cell-based studies. RESULTS: Among 80 patients enrolled, 72 (90%) patients were evaluable: 7 achieved partial response (PR) (10%) and 37 had stable disease (SD) (51%; duration range: 1-27 cycles). Clinical benefit (SD or PR ≥ 6 months) was observed in 26 evaluable patients [36%, 95% confidence intervals (CI) (25% to 49%)]. In 80 patients, median overall survival (OS) was 10.5 months [95% CI (8.5-16.1)] and median progression-free survival (PFS) 4.1 months [95% CI (3.4-7.3)]. Six patients (7.5%) experienced DLTs and 20 (25%) required dose modifications. VAN + EV was safe, with fatigue, rash, diarrhea, and mucositis being the most common toxicities. In cell-based studies, combination therapy was superior to monotherapy at inhibiting cancer cell proliferation and intracellular signaling. CONCLUSIONS: The MTDs and RP2Ds of VAN + EV are 300 mg and 10 mg, respectively. VAN + EV combination is safe and active in refractory solid tumors. Further investigation is warranted in RET pathway aberrant tumors.


Asunto(s)
Everolimus , Neoplasias , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos , Everolimus/efectos adversos , Humanos , Neoplasias/tratamiento farmacológico , Piperidinas , Proto-Oncogenes Mas , Quinazolinas , Factor A de Crecimiento Endotelial Vascular/uso terapéutico
19.
Biotechnol Bioeng ; 106(5): 794-803, 2010 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-20564616

RESUMEN

Tissue engineered materials for clinical purposes have led to the development of in vitro models as alternatives to animal testing. The aim of this study was to understand the paracrine interactions arising between keratinocytes and fibroblasts for detecting and discriminating between an irritant-induced inflammatory reaction and cytotoxicity. We used two irritants [sodium dodecyl sulphate (SDS) and potassium diformate (Formi] at sub-toxic concentrations and studied interleukin-1 alpha (IL-1 alpha) release from human keratinocytes and activation of NF-kappaB in human fibroblasts. NF-kappaB activation in fibroblast 2D cultures required soluble factors released by prior incubation of keratinocytes with either SDS or Formi. Neither cell type responded directly to either agent, confirming a paracrine mechanism. Fibroblasts were then cultured in 3D microfiber scaffolds and transfected with an NF-kappaB reporter construct linked to GFP. Findings for 3D cultures were similar to those in 2D in that soluble factors released by prior incubation of keratinocytes with SDS or Formi was required for NF-kappaB activation in fibroblasts. Similarly, direct incubation with either agent did not directly activate NF-kappaB. A technical advantage of using transfected cells in 3D was an ability to detect NF-kappaB activation in live fibroblasts. To confirm paracrine signaling a twofold increase in IL-1 alpha was measured in keratinocyte-conditioned medium after incubation with SDS or Formi, which correlated with fibroblast NF-kappaB activity. In summary, this work has value for developing 3D tissue engineered co-culture models for the in vitro testing of irritant chemicals at sub-toxic concentrations, as an alternative to in vivo models.


Asunto(s)
Irritantes/toxicidad , Piel/efectos de los fármacos , Técnicas de Cultivo de Célula , Técnicas de Cocultivo , Fibroblastos/efectos de los fármacos , Genes Reporteros , Humanos , Queratinocitos/efectos de los fármacos , FN-kappa B/metabolismo , Técnicas de Cultivo de Órganos , Factores de Tiempo
20.
Clin Exp Dermatol ; 35(8): 892-6, 2010 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-20456402

RESUMEN

Primary cutaneous peripheral T-cell lymphomas (PTL), unspecified, are rare lymphomas, with a poor prognosis. They grow and disseminate rapidly, leading to widespread disease. We report a case of PTL, unspecified occurring on the nose. Despite its aggressive histology, this tumour behaved indolently. It is remarkably similar, clinically and histologically, to four recently described cases that occurred on the ear.


Asunto(s)
Linfoma Cutáneo de Células T/patología , Linfoma de Células T Periférico/patología , Neoplasias Nasales/patología , Neoplasias Cutáneas/patología , Anciano de 80 o más Años , Femenino , Humanos , Linfoma Cutáneo de Células T/radioterapia , Linfoma de Células T Periférico/radioterapia , Neoplasias Nasales/radioterapia , Radioterapia Conformacional/métodos , Neoplasias Cutáneas/radioterapia
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