Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 170
Filtrar
Más filtros

Tipo del documento
Intervalo de año de publicación
1.
Chemistry ; 30(30): e202400896, 2024 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-38507133

RESUMEN

Directional bonding strategies guide the design of complex molecular architectures, yet challenges arise due to emergent behavior. Rigid structures face geometric constraints and sensitivity to mismatches, hindering the efficient assembly of molecular organic cages (MOCs). Harnessing intramolecular non-covalent interactions offers a promising solution, broadening geometrical possibilities and enhancing adaptability to boost assembly yields. However, identifying these interactions remains challenging, with their full potential sometimes latent until final assembly. This study explores these challenges by synthesizing boronic acid tripods with varied oxygen positions at the tripodal feet and investigating their role in assembling tetrahedral boronate MOCs. Our results reveal substantial differences in the assembly efficiency among tripods. While the building blocks with oxygen in the benzylic position relative to the central aromatic ring form the MOCs in high yields, those with the oxygen atom directly bound to the central aromatic ring, only yield traces. Through X-ray crystallography and DFT analyses, we elucidate how intramolecular interactions profoundly influence the geometry of the building blocks and cages in a relay-like fashion, highlighting the importance of considering intramolecular interactions in the rational design of (supra)molecular architectures.

2.
Clin Anat ; 2024 Mar 12.
Artículo en Inglés | MEDLINE | ID: mdl-38469730

RESUMEN

Current advances in the management of the autonomic nervous system in various cardiovascular diseases, and in treatments for pain or sympathetic disturbances in the head, neck, or upper limbs, necessitate a thorough understanding of the anatomy of the cervicothoracic sympathetic trunk. Our objective was to enhance our understanding of the origin and distribution of communicating branches and visceral cervicothoracic sympathetic nerves in human fetuses. This was achieved through a comprehensive topographic systematization of the branching patterns observed in the cervical and upper thoracic ganglia, along with the distribution of communicating branches to each cervical spinal nerve. We conducted detailed sub-macroscopic dissections of the cervical and thoracic regions in 20 human fetuses (40 sides). The superior and cervicothoracic ganglia were identified as the cervical sympathetic ganglia that provided the most communicating branches on both sides. The middle and accessory cervical ganglia contributed the fewest branches, with no significant differences between the right and left sides. The cervicothoracic ganglion supplied sympathetic branches to the greatest number of spinal nerves, spanning from C5 to T2 . The distribution of communicating branches to spinal nerves was non-uniform. Notably, C3 , C4 , and C5 received the fewest branches, and more than half of the specimens showed no sympathetic connections. C1 and C2 received sympathetic connections exclusively from the superior ganglion. Spinal nerves that received more branches often did so from multiple ganglia. The vertebral nerve provided deep communicating branches primarily to C6 , with lesser contributions to C7 , C5 , and C8 . The vagus nerve stood out as the cranial nerve with the most direct sympathetic connections. The autonomic branching pattern and connections of the cervicothoracic sympathetic trunk are significantly variable in the fetus. A comprehensive understanding of the anatomy of the cervical and upper thoracic sympathetic trunk and its branches is valuable during autonomic interventions and neuromodulation. This knowledge is particularly relevant for addressing various autonomic cardiac diseases and for treating pain and vascular dysfunction in the head, neck, and upper limbs.

3.
J Org Chem ; 88(4): 2113-2121, 2023 Feb 17.
Artículo en Inglés | MEDLINE | ID: mdl-36730713

RESUMEN

For molecular architectures based on dynamic covalent chemistry (DCvC), strict preorganization is a paradigmatic concept and the generally accepted strategy for their rational design. This results in the creation of highly rigid building blocks which are expected to fulfill the ideal geometry of the assembly, coming at a price that small geometric mismatches result in unpredicted and/or unproductive reaction outcomes. In this study, we show that feet of a tripodal platform have a great influence on the assembly of tetrahedral organic cages based on boronate ester formation. The aryl benzyl ether-functionalized building blocks perform significantly better than their alkyl-functionalized equivalents. Experimentally and using density functional theory geometry optimization of the cage structures, we prove that unexpectedly, this is not due to solubility but because of the enhanced capability of the aryl benzyl ether-functionalized building blocks to fit the ideal geometry of the assembly. This introduces the concept of building block adaptability to overcome geometrical mismatches in DCvC systems.

4.
J Card Surg ; 37(1): 39-46, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34652039

RESUMEN

OBJECTIVE: Valve-sparing root replacement is commonly used for management of aortic root aneurysms in elective setting, but its technical complexity hinders its broader adoption for acute type-A aortic dissection (ATAAD). The Florida sleeve (FS) procedure is a simplified form of valve sparing aortic root reconstruction that does not require coronary reimplantation. Here, we present our outcomes of the FS repair in patients with dilated roots in the setting of an ATAAD. METHODS: We retrospectively reviewed 24 consecutive patients (2002-2018) treated with FS procedure for ATAAD. Demographic, operative, and postoperative outcomes were queried from our institutional database. Long term follow-up was obtained from clinic visits for local patients, and with telephone and telehealth measures otherwise. RESULTS: Mean age was 49 ± 14 years with 19 (79%) males. Marfan syndrome was present in 4 (16.7%) patients and 14 (58.3) had ≥2+ aortic insufficiency (AI). Nine (37.2%) had preoperative mal-perfusion or shock. The FS was combined with hemi-arch replacement in 15 (62.5%) patients and a zone-2 arch replacement in 9 (37.5%) patients. There were 2 (8.3%) early postoperative mortalities. Median follow-up period was 46 months (range, 0.3-146). The median survival of the entire cohort was 143.4 months. One patient (4.2%) required redo aortic valve replacement for unrelated aortic valve endocarditis at 30 months postoperatively. CONCLUSION: FS is simplified and reproducible valve-sparing root repair. In appropriate patients, it can be applied safely in acute Stanford type-A aortic dissection with excellent early and long-term results.


Asunto(s)
Aneurisma de la Aorta Torácica , Disección Aórtica , Insuficiencia de la Válvula Aórtica , Adulto , Disección Aórtica/cirugía , Aneurisma de la Aorta Torácica/cirugía , Válvula Aórtica/diagnóstico por imagen , Válvula Aórtica/cirugía , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Resultado del Tratamiento
5.
J Card Surg ; 37(10): 3279-3286, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-35894828

RESUMEN

BACKGROUND: With evolutions in technique, recent data encourage the use of cerebral perfusion during aortic arch repair. However, a randomized data have demonstrated higher rates of neurologic injury according to MRI lesions using antegrade cerebral perfusion during hemiarch reconstruction. METHODS: This was a retrospective review of two institutional aortic center databases to identify adult patients who underwent aortic hemiarch reconstruction for elective aortic aneurysm or acute type A aortic dissection. Patients were stratified according to cerebral protection method: (1) deep hypothermic circulatory arrest (DHCA) group versus (2) DHCA/retrograde cerebral perfusion (RCP) group. RESULTS: A total of 320 patients and 245 patients underwent hemiarch reconstruction for aortic aneurysm electively and aortic dissection, respectively. In aneurysmal pathology, the DHCA group included 133 patients and the DHCA/RCP group included 187 patients. Operative mortality was 0.8% in the DHCA group and 2.7% in the DHCA/RCP group (p = 0.41). Kaplan-Meier survival estimates revealed comparable 2-year survival (p = 0.14). In dissection, 43 patients and 202 patients were included in the DHCA group and the DHCA/RCP group, respectively. Operative mortality was equivalent between the two groups (11.6% in the DHCA group and 9.4% in the DHCA/RCP group, p = 0.58). Long-term survival was similar at 2 years between the groups (p = 0.06). Multivariable analysis showed cerebral perfusion strategy was not associated with the composite outcome of operative mortality and stroke. CONCLUSIONS: In treating both elective and acute ascending aortic pathologies with hemiarch reconstruction, both DHCA alone or in combination with RCP yield comparable results.


Asunto(s)
Aneurisma de la Aorta Torácica , Disección Aórtica , Adulto , Disección Aórtica/cirugía , Aorta Torácica/cirugía , Aneurisma de la Aorta Torácica/cirugía , Circulación Cerebrovascular , Paro Circulatorio Inducido por Hipotermia Profunda/métodos , Mortalidad Hospitalaria , Humanos , Perfusión/métodos , Estudios Retrospectivos , Resultado del Tratamiento
6.
J Card Surg ; 37(12): 4545-4551, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36378930

RESUMEN

PURPOSE: There have been reported reductions of hospital presentation for acute cardiovascular conditions such as myocardial infarction and acute type A aortic dissection (ATAAD) in the United States during the COVID-19 pandemic. This study examined presentation patterns and outcomes of ATAAD in North America immediately before, and during, the COVID-19 pandemic. METHODS: The Society of Thoracic Surgeons Adult Cardiac Surgery Database (STS ACSD) was queried to identify patients presenting with ATAAD in the 12 months pre-pandemic (March 2019-February 2020), and during the early pandemic (March through June 2020). Demographics and operative characteristics were compared using χ² test and Wilcoxon Rank-sum test. The median annual case volume designated low-volume centers versus high-volume centers (>10 cases per month). Step-wise variable selection was used to create a risk set used for adjustment of all multivariable models. RESULTS: There were 5480 patients identified: 4346 pre-pandemic and 1134 during pandemic. There was significantly lower volume of median cases per month during the COVID-19 pandemic period (286 interquartile range [IQR]: 256-306 vs. 372 IQR: 291-433,p = .0152). In historically low-volume centers (<10 cases per year), there was no difference in volume between the two periods (142 IQR: 133-166 vs. 177 IQR: 139-209, p = NS). In high-volume centers, there was a decline during the pandemic (140 IQR: 123-148 vs. 212 IQR: 148-224, p = .0052). There was no difference in overall hospital-to-hospital transfers during the two time periods (54% of cases pre-pandemic, 55% during). Patient demographics, operative characteristics, malperfusion rates, and cardiac risk factors were similar between the two time periods. There was no difference in unadjusted operative mortality (19.01% pre-pandemic vs. 18.83% during, p = .9) nor major morbidity (52.42% pre-pandemic vs. 51.24% during, p = .5). Risk-adjusted multivariable models showed no difference in either operative mortality nor major morbidity between time periods. CONCLUSIONS: For patients presenting to the hospital with ATAAD during the first surge of the pandemic, operative outcomes were similar to pre-pandemic despite a 30% reduction in volume. Out-of-hospital mortality from ATAAD during the pandemic remains unknown. Further understanding these findings will inform management of ATAAD during future pandemics.


Asunto(s)
Disección Aórtica , COVID-19 , Cirujanos , Adulto , Humanos , Estados Unidos/epidemiología , Pandemias , Resultado del Tratamiento , Estudios Retrospectivos , COVID-19/epidemiología , Disección Aórtica/epidemiología , Disección Aórtica/cirugía
7.
Neuroendocrinology ; 111(10): 925-936, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33040060

RESUMEN

BACKGROUND: Craniopharyngioma (CP) is a rare tumor in the elderly whose clinical features and prognosis are not well known in this population. AIM: To evaluate the clinicopathological features and therapeutic outcomes of CP diagnosed in the elderly. PATIENTS AND METHODS: This was a retrospective, multicenter, national study of CP patients diagnosed over the age of 65 years and surgically treated. RESULTS: From a total of 384 adult CP patients, we selected 53 (13.8%) patients (27 women [50.9%], mean age 72.3 ± 5.1 years [range 65-83 years]) diagnosed after the age of 65 years. The most common clinical symptoms were visual field defects (71.2%) followed by headache (45.3%). The maximum tumor diameter was 2.9 ± 1.1 cm. In most patients, the tumor was suprasellar (96.2%) and mixed (solid-cystic) (58.5%). The surgical approach most commonly used was transcranial surgery (52.8%), and more than half of the patients (54.7%) underwent subtotal resection (STR). Adamantinomatous CP and papillary CP were present in 51 and 45.1%, respectively, with mixed forms in the remaining. Surgery was accompanied by an improvement in visual field defects and in headaches; however, pituitary hormonal hypofunction increased, mainly at the expense of an increase in the prevalence of diabetes insipidus (DI) (from 3.9 to 69.2%). Near-total resection (NTR) was associated with a higher prevalence of DI compared with subtotal resection (87.5 vs. 53.6%, p = 0.008). Patients were followed for 46.7 ± 40.8 months. The mortality rate was 39.6% with a median survival time of 88 (95% CI: 57-118) months. DI at last visit was associated with a lower survival. CONCLUSION: CP diagnosed in the elderly shows a similar distribution by sex and histologic forms than that diagnosed at younger ages. At presentation, visual field alterations and headaches are the main clinical symptoms which improve substantially with surgery. However, surgery, mainly NTR, is accompanied by worsening of pituitary function, especially DI, which seems to be a predictor of mortality in this population.


Asunto(s)
Envejecimiento , Craneofaringioma , Neoplasias Hipofisarias , Anciano , Anciano de 80 o más Años , Craneofaringioma/diagnóstico , Craneofaringioma/mortalidad , Craneofaringioma/patología , Craneofaringioma/terapia , Femenino , Humanos , Masculino , Neoplasias Hipofisarias/diagnóstico , Neoplasias Hipofisarias/mortalidad , Neoplasias Hipofisarias/patología , Neoplasias Hipofisarias/terapia , Estudios Retrospectivos , España/epidemiología
8.
Molecules ; 26(6)2021 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-33804118

RESUMEN

Cyclic products can be obtained through the intramolecular version of the Nicholas reaction, which requires having the nucleophile connected to the alkyne unit. Here, we report the synthesis of 1-oxa-3-cyclooctynes starting from commercially available (1R,3S)-camphoric acid. The strategy is based on the initial preparation of propargylic alcohols, complexation of the triple bond with Co2(CO)8, and treatment with BF3·Et2O to induce an intramolecular Nicholas reaction with the free hydroxyl group as nucleophile. Finally, oxidative deprotection of the alkyne afforded the cyclooctynes in good yields. Notably, large-sized R substituents at the chiral center connected to the O atom were oriented in such a way that steric interactions were minimized in the cyclization, allowing the formation of cyclooctynes exclusively with (R) configuration, in good agreement with theoretical predictions. Moreover, preliminary studies demonstrated that these cyclooctynes were reactive in the presence of azides yielding substituted triazoles.

9.
J Card Surg ; 35(7): 1714-1716, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-32557775

RESUMEN

OBJECTIVE: This study highlights the management strategy in simultaneous bicuspid aortic valve infective endocarditis and mycotic pseudoaneurysm of an aortic coarctation. METHODS: A staged repair of mycotic pseudoaneurysm of aortic coarctation and infective bicuspid aortic valve endocarditis. RESULTS: We present a 19-year old gentleman who was admitted with aching pain in his bilateral lower extremities with associated purpuric rash and fevers. Work-up was significant for severe aortic valve regurgitation and a pseudoaneurysm in the distal aortic arch. He underwent operative repair through a left posterior-lateral thoracotomy with femoral-femoral partial cardiopulmonary bypass. Intraoperative findings were significant for a juxta-ductal coarctation and pseudoaneurysm. The mycotic pseudoaneurysm and remnant ligamentum arteriosum were completely resected and were replaced with a 18 mm Gelweave graft (Terumo Cardiovascular Group, Ann Arbor, MI) from the distal arch to the descending thoracic aorta. The patient underwent a planned secondary washout and omental flap for biologic coverage of the graft. Subsequently, a staged aortic valve replacement was completed 1 week later. The patient's postoperative course was uncomplicated, and he was discharged with intact motor and sensory function. CONCLUSIONS: A staged approach is a prudent strategy to manage a patient with simultaneous endocarditis and aortic mycotic pseudoaneurysm, with precedence toward the most critical lesion.


Asunto(s)
Aneurisma Falso/cirugía , Coartación Aórtica/cirugía , Válvula Aórtica/cirugía , Implantación de Prótesis Vascular/métodos , Endocarditis/cirugía , Implantación de Prótesis de Válvulas Cardíacas/métodos , Aneurisma Falso/complicaciones , Coartación Aórtica/complicaciones , Puente Cardiopulmonar , Endocarditis/complicaciones , Humanos , Masculino , Reoperación , Colgajos Quirúrgicos , Toracotomía , Resultado del Tratamiento , Adulto Joven
10.
J Card Surg ; 35(8): 2070-2072, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32652682

RESUMEN

OBJECTIVE: Highlight our management of a Pasteurella Multiocida-infected descending thoracic aorta mycotic pseudoaneurysm. METHODS: Report a case of a canine bite resulting in a P. Multiocida descending thoracic aorta mycotic pseudoaneurysm. RESULTS: We present a 61-year-old gentleman who was initially seen in an emergency department after a canine bite. He was admitted and treated with a course of IV antibiotics for P. Multiocida bacteremia and discharged. Three weeks after discharge, he continued to feel generalized malaise and work-up was significant for a descending thoracic aorta mycotic pseudoaneurysm. The patient underwent a low left posterior lateral thoracotomy and femoral-femoral cardiopulmonary bypass for complete pseudoaneurysm resection and aortic replacement with a 24-mm Gelweave graft. Given purulence and gross infection, we planned for a staged approach, with a secondary washout and omental flap for biologic coverage of the graft. The patient did well clinically and was discharged at 14 days to rehabilitation with 6-week intravenous course of antibiotics. CONCLUSIONS: The patient's clinical course with subsequent follow-up suggest that complete resection of the mycotic pseudoaneurysm, followed by omental flap coverage is a viable strategy to manage mycotic aortic infections with virulent organisms.


Asunto(s)
Aneurisma Falso/etiología , Aneurisma Falso/cirugía , Aneurisma Infectado/etiología , Aneurisma Infectado/cirugía , Aorta Torácica/cirugía , Aneurisma de la Aorta Torácica/etiología , Aneurisma de la Aorta Torácica/cirugía , Bacteriemia/etiología , Mordeduras y Picaduras/complicaciones , Infecciones por Pasteurella/etiología , Infecciones por Pasteurella/cirugía , Pasteurella multocida , Animales , Implantación de Prótesis Vascular/métodos , Puente Cardiopulmonar , Perros , Humanos , Masculino , Persona de Mediana Edad , Colgajos Quirúrgicos , Toracotomía/métodos
11.
J Card Surg ; 35(4): 934-936, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32107790

RESUMEN

Acute DeBakey I or II aortic dissection (AD) is a surgical emergency with significant mortality if not repaired immediately. We present the case of a 49-year-old man with acute type I AD, who initially underwent zone 2 arch replacement for a primary arch tear. A calcified ductus arteriosus was noted during arch reconstruction. He exhibited exsanguinating hemorrhage from the proximal descending thoracic aorta upon an initial attempt to wean off cardiopulmonary bypass. Hemostasis was achieved with retrograde transfemoral thoracic endovascular aortic repair and transmediastinal external cinch around the descending aorta to obliterate false lumen flow.


Asunto(s)
Aorta Torácica/cirugía , Disección Aórtica/complicaciones , Disección Aórtica/cirugía , Implantación de Prótesis Vascular/métodos , Prótesis Vascular , Procedimientos Endovasculares/métodos , Hemorragia/etiología , Hemorragia/cirugía , Hemostasis Quirúrgica/métodos , Enfermedad Aguda , Disección Aórtica/clasificación , Disección Aórtica/diagnóstico por imagen , Puente Cardiopulmonar , Humanos , Masculino , Persona de Mediana Edad , Tomografía Computarizada por Rayos X , Resultado del Tratamiento
12.
J Card Surg ; 35(4): 854-859, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32115823

RESUMEN

OBJECTIVE: The index for mortality prediction after cardiac transplantation (IMPACT) risk score incorporates 12 preoperative recipient-specific variables, and has been validated as an accurate predictor of short- and long-term mortality after orthotopic heart transplantation (OHTx). We believe it can also be used to predict hospital costs, and we hypothesize that higher preoperative IMPACT risk scores are associated with increased hospital resource consumption. METHODS: All OHTx patients ≥18 years of age at our institution were reviewed from 1 January 2000 to 31 December 2014. Total index hospitalization costs post-transplant were extracted and presented in 2014 consumer price index inflation-adjusted US dollars. Patients were stratified into quartiles (Q) according to IMPACT risk scores. Logarithmic transformation normalized cost data, and linear regression assessed for correlation. A comparison of cost between Q of IMPACT risk score was performed using rank-sum and Kruskal-Wallis tests. Survival was estimated using the Kaplan-Meier method. RESULTS: Three hundred fifty-six (n = 356) OHTx were performed during the study period. The median IMPACT score for the cohort was five (interquartile range [IQR] 3-6). Eight (2.2%) patients died within 30-days and 1-year Kaplan-Meier survival was 88.3%. The median length of stay (LOS) was 16 (IQR 14-24) days. The median hospital cost for index admission was $222 200 (IQR:$169 200-$313 700). Median LOS was longer in Q4 vs Q1 (18 days vs 15 days, P = .01) and index hospital costs in Q4 were significantly higher compared to Q1 patients ($280 400 vs $205 000, P < .01). There was a significant positive correlation between IMPACT risk score and cost (regression coefficient .04, P < .01). CONCLUSION: This is the first study in adult cardiac transplantation to identify a positive correlation between hospital cost and recipient risk using the IMPACT risk score. Cost and resource consumption for the index admission after OHTx were significantly higher in the highest IMPACT risk Q compared with patients in the lowest Q.


Asunto(s)
Economía/estadística & datos numéricos , Recursos en Salud/economía , Recursos en Salud/estadística & datos numéricos , Insuficiencia Cardíaca/economía , Insuficiencia Cardíaca/cirugía , Trasplante de Corazón/economía , Trasplante de Corazón/mortalidad , Costos de Hospital , Adolescente , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Periodo Preoperatorio , Calidad de la Atención de Salud/estadística & datos numéricos , Riesgo , Tasa de Supervivencia , Factores de Tiempo , Adulto Joven
13.
Angew Chem Int Ed Engl ; 59(39): 17077-17083, 2020 09 21.
Artículo en Inglés | MEDLINE | ID: mdl-32573884

RESUMEN

Inverting the reactivity of the functional groups in ambiphilic molecules provides a new synthetic strategy to perform late-stage enantiodivergence. Both enantiomers of the final compound can be obtained from a common chiral precursor. As a proof of concept, the synthesis of substituted five- and six-membered oxacycles is described. The key step is the cyclization of an ambiphilic linear precursor bearing a propargylic alcohol and an epoxide linked through an alkyl chain. Through a slight modification of these linear precursors and employing different reaction conditions, these functional groups can inverse their chemical reactivity, producing one enantiomer or another of the final product. This enantiodivergent cyclization involves three stereogenic centers that can undergo fully controlled retention or inversion of their configuration depending on the cyclization pathway that is activated. The cyclization provides late-stage enantiodivergence, enabling the synthesis of either enantiomers of the oxacycles from a common chiral substrate with total transfer of the enantiomeric purity.

15.
J Card Surg ; 34(1): 28-30, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30625255

RESUMEN

We present an endovascular technique to repair an ascending aortic pseudoaneurysm in a patient with multiple previous sternotomies using access via the right common carotid artery.


Asunto(s)
Aneurisma Falso/cirugía , Aneurisma de la Aorta Torácica/cirugía , Procedimientos Endovasculares/métodos , Stents , Anciano , Aneurisma Falso/diagnóstico , Aneurisma de la Aorta Torácica/diagnóstico , Aortografía/métodos , Arteria Carótida Común , Femenino , Humanos , Diseño de Prótesis
16.
Faraday Discuss ; 210(0): 409-428, 2018 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-29974088

RESUMEN

Atomic force microscopes (AFMs) are capable of high-resolution mapping of structures and the measurement of mechanical properties on nanometre scales within gaseous, liquid and vacuum environments. The contact mode high-speed AFM (HS-AFM) developed at Bristol Nano Dynamics Ltd. operates at speeds that are orders of magnitude faster than conventional AFMs, and is capable of capturing multiple frames per second. This allows for direct observation of dynamic events in real-time, with nanometre lateral resolution and subatomic height resolution. HS-AFM is a valuable tool for the imaging of nanoscale corrosion initiation events, such as metastable pitting, grain boundary (GB) dissolution and short crack formation during stress corrosion cracking (SCC). Within this study HS-AFM was combined with SEM and FIB milling to produce a multifaceted picture of localised corrosion events occurring on thermally sensitised AISI 304 stainless steel in an aqueous solution of 1% sodium chloride (NaCl). HS-AFM measurements were performed in situ by imaging within a custom built liquid cell with parallel electrochemical control. The high resolution of the HS-AFM allowed for measurements to be performed at individual reaction sites, i.e. at specific GB carbide surfaces. Topographic maps of the sample surface allowed for accurate measurements of the dimensions of pits formed. Using these measurements it was possible to calculate, and subsequently model, the volumes of metal reacting with respect to time, and so the current densities and ionic fluxes at work. In this manner, the local electrochemistry at nanoscale reaction sites may be reconstructed.

17.
J Gene Med ; 19(4)2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-28306219

RESUMEN

BACKGROUND: We identified a new and a recurrent POLD1 mutation associated with predisposition to colorectal cancer (CRC). We characterized the molecular and clinical nature of the potential POLD1 founder mutation in families from Valencia (Spain). METHODS: Clinical and molecular data were collected from four independent families known to have a POLD1 Leu474Pro mutation. To establish its founder effect, haplotype construction was performed using 14 flanking POLD1 polymorphic markers. We calculated penetrance estimates and clinical expressivity, globally and stratified by age and sex. RESULTS: We included 32 individuals from the four families: 20 carriers and 12 noncarriers. A common haplotype was identified in these families in a region comprising 2,995 Mb, confirming L474P as the first founder POLD1 mutation identified. Thirteen tumors diagnosed in 10 POLD1 carriers: eight CRC, three endometrial and two other tumors were considered. The median age of cancer onset for POLD1 mutation carriers was 48 years. The observed penetrance was 50% and the cumulative risk at age of 50 years was 30%. CONCLUSIONS: The findings of the present study contribute to a better understanding of CRC genetics in the Spanish population. The clinical phenotype for this mutation is similar to that in Lynch syndrome. Future studies using next generation sequencing with large gene panels for any hereditary cancer condition will offer the possibility of detecting POLE/POLD1 mutations in unsuspected clinical situations, demonstrating a more real and unbiased picture of the associated phenotype.


Asunto(s)
ADN Polimerasa III/genética , Efecto Fundador , Genética de Población , Mutación Missense , Población Blanca/genética , Adulto , Anciano , Anciano de 80 o más Años , Neoplasias Colorrectales Hereditarias sin Poliposis/diagnóstico , Neoplasias Colorrectales Hereditarias sin Poliposis/epidemiología , Neoplasias Colorrectales Hereditarias sin Poliposis/genética , Femenino , Predisposición Genética a la Enfermedad , Mutación de Línea Germinal , Haplotipos , Heterocigoto , Humanos , Masculino , Repeticiones de Microsatélite , Persona de Mediana Edad , Penetrancia , Fenotipo , Polimorfismo de Nucleótido Simple , Vigilancia de la Población , España , Adulto Joven
18.
J Card Surg ; 32(5): 274-280, 2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-28417489

RESUMEN

BACKGROUND AND AIM: Septic emboli (SE) associated with infectious endocarditis (IE) can result in splenic abscesses and infectious intracranial aneurysms (IIA). We investigated the impact of SE on patient outcomes following surgery for IE. METHOD: From January-2000 to October-2015, all patients with surgical IE (n = 437) were evaluated for incidence and management of SE. RESULTS: Overall SE was found in 46/437 (10.52%) patients (n = 17 spleen, 13 brain, and 16 both). No mortality was seen in the brain emboli groups, but in the splenic abscess group the in-hospital mortality was 8.69% (n = 4); and was associated with Age >35 (OR = 2.63, 1.65-4.20) and congestive heart failure (OR = 14.40, 1.23-168.50). Patients with splenic emboli had excellent mid-term outcome following discharge (100% survival at 4-years). Splenic emboli requiring splenectomy was predicted by a >20 mm valve vegetation (OR = 1.37, 1.056-1.77) and WBC >12000 cells/mm (OR = 5.58, 1.2-26.3). No patient with streptococcus-viridians infection had a nonviable spleen (OR = 0.67, 0.53-0.85). Postoperative acute-kidney-injury was higher in the splenectomy group (45.45% vs 9%) (p = 0.027). There were 6 patients with symptomatic IIAs that required coiling/clipping which was associated with age <30 years, (OR = 6.09, 1.10-33.55). Survival in patients with cerebral emboli decreased to 78% at 3-4 years. Patients with both splenic and brain emboli had a 92% survival rate at 1-year and 77% at 2-4 years. CONCLUSION: Septic emboli is common in endocarditis patients. Patients with high preoperative WBC level and large valve vegetations require CT imaging of the spleen. Both spleen and brain interventions in the setting of IE can be performed safely with excellent early and mid-term outcomes.


Asunto(s)
Embolia/etiología , Endocarditis/complicaciones , Endocarditis/cirugía , Embolia Intracraneal/etiología , Bazo/irrigación sanguínea , Absceso/epidemiología , Absceso/etiología , Absceso/mortalidad , Absceso/cirugía , Adulto , Factores de Edad , Anciano , Embolia/epidemiología , Embolia/mortalidad , Embolia/cirugía , Femenino , Insuficiencia Cardíaca , Válvulas Cardíacas/cirugía , Humanos , Incidencia , Aneurisma Intracraneal/epidemiología , Aneurisma Intracraneal/etiología , Aneurisma Intracraneal/mortalidad , Aneurisma Intracraneal/cirugía , Embolia Intracraneal/epidemiología , Embolia Intracraneal/mortalidad , Recuento de Leucocitos , Masculino , Persona de Mediana Edad , Procedimientos Neuroquirúrgicos , Pronóstico , Esplenectomía , Enfermedades del Bazo/epidemiología , Enfermedades del Bazo/etiología , Enfermedades del Bazo/mortalidad , Enfermedades del Bazo/cirugía , Tasa de Supervivencia , Adulto Joven
19.
Microsc Microanal ; 23(2): 227-237, 2017 04.
Artículo en Inglés | MEDLINE | ID: mdl-28441978

RESUMEN

The local electrode atom probe (LEAP) has become the primary instrument used for atom probe tomography measurements. Recent advances in detector and laser design, together with updated hit detection algorithms, have been incorporated into the latest LEAP 5000 instrument, but the implications of these changes on measurements, particularly the size and chemistry of small clusters and elemental segregations, have not been explored. In this study, we compare data sets from a variety of materials with small-scale chemical heterogeneity using both a LEAP 3000 instrument with 37% detector efficiency and a 532-nm green laser and a new LEAP 5000 instrument with a manufacturer estimated increase to 52% detector efficiency, and a 355-nm ultraviolet laser. In general, it was found that the number of atoms within small clusters or surface segregation increased in the LEAP 5000, as would be expected by the reported increase in detector efficiency from the LEAP 3000 architecture, but subtle differences in chemistry were observed which are attributed to changes in the way multiple hit detection is calculated using the LEAP 5000.

20.
J Wound Care ; 26(3): 121-125, 2017 Mar 02.
Artículo en Inglés | MEDLINE | ID: mdl-28277999

RESUMEN

OBJECTIVE: The aim of this study was to quantify blood cells and inflammatory markers, involved in the healing process, in exudates from wounds in different healing phases, to assess these markers in order to identify the inflammatory phase of the wounds. METHOD: Patients who presented with postsurgical wounds, which closed by first and second intention, and those who presented with pressure ulcers (PUs), which were closed by second intention, were included in the study. RESULTS: We examined wounds from 37 patients and collected samples from 52 wounds in the inflammatory phase, 30 in the proliferative phase and 29 in the maturation phase. The number of neutrophils and platelets in the exudate collected from wounds in the inflammatory phase was significantly higher (p<0.001), while the number of lymphocytes, was significantly lower in exudate from wounds in the inflammatory phase (p<0.001). Wound c-reactive protein (CRP) and immunoglobulin G (IgG) levels were higher in the inflammatory group (p<0.001). We found a significantly positive correlation between CRP levels and the percentage of neutrophils and monocytes (r=0.346, p=0.004; r=0.293, p=0.015), and a significantly negative correlation between CRP levels and the percentage of lymphocytes (r=-0.503, p<0.001). A stepwise logistic regression analysis was used to identify an optimal combination of these biomarkers. The optimal biomarker combinations were neutrophils + monocytes + platelets + IgG + CRP, with an area under the curve (AUC) of 0.981 [confidence interval (CI) 95%: 0.955-1.000, p<0.001] for the diagnosis of wounds in the inflammatory phase. The optimal cutpoint yielded 96.9 % sensitivity and 94.6 % specificity. The biomarker combination predicted the inflammatory phase and was superior to individual biomarkers. CONCLUSION: Our findings suggest that the combination of the markers, percentage of neutrophils and monocytes, platelets, CRP and IgG levels could be useful prognostic indicators of the inflammatory phase.


Asunto(s)
Biomarcadores/sangre , Inflamación/sangre , Úlcera por Presión/sangre , Cicatrización de Heridas , Citocinas/sangre , Femenino , Humanos , Masculino , Heridas y Lesiones/sangre
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA