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1.
Ann Surg Oncol ; 2024 Mar 23.
Artículo en Inglés | MEDLINE | ID: mdl-38520583

RESUMEN

BACKGROUND: Limb-sparing resections of thigh soft tissue sarcomas (STSs) can result in adverse outcomes. Identifying preoperative predictors for wound healing complications, tumor recurrence, and mortality is crucial for informed reconstructive decision-making. We hypothesized that preoperative measurements of thigh and tumor dimensions could serve as reliable indicators for postoperative complications, recurrence, and death. PATIENTS AND METHODS: In this retrospective cohort study conducted from March 2016 to December 2021, we analyzed patients undergoing thigh STS excisions followed by reconstruction. Preoperative magnetic resonance imaging or computed tomography scans provided necessary thigh and tumor dimensions. Univariate and multivariate regression assessed relationships between these dimensions and postoperative outcomes, including complications, recurrence, and death. RESULTS: Upon the analysis of 123 thighs, we found thigh width to be highly predictive of postoperative complications, even surpassing body mass index (BMI) and retaining significance in multivariate regression [odds ratio (OR) 1.19; 95% CI 1.03-1.39; p = 0.03]. Sarcoma-to-thigh width and thickness ratios predicted STS recurrence, with the thickness ratio retaining significance in multivariate regression (OR 1.03; 95% CI 1.001-1.05; p = 0.041). Notably, greater thigh thickness was independently protective against mortality in multivariate analysis (OR 0.80; 95% CI 0.65-0.98; p = 0.030). CONCLUSIONS: Thigh width outperformed BMI in association with postoperative complications. This may create an opportunity for intervention, where weight loss can play a role during the neoadjuvant therapy period to potentially reduce complications. Sarcoma-to-thigh width and thickness ratios, particularly the latter, hold substantial predictive value in terms of STS recurrence. Moreover, thigh thickness is an independent predictor of survival.

2.
J Org Chem ; 89(1): 163-173, 2024 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-38087461

RESUMEN

We report the synthesis of a new set of amphiphilic saddle-shaped heptagon-containing polycyclic aromatic hydrocarbons (PAHs) functionalized with tetraethylene glycol chains and their self-assembly into large two-dimensional (2D) polymers. An in-depth analysis of the self-assembly mechanism at the air/water interface has been carried out, and the proposed arrangement models are in good agreement with the molecular dynamics simulations. Quite remarkably, the number and disposition of the tetraethylene glycol chains significantly influence the disposition of the PAHs at the interface and conditionate their packing under pressure. For the three compounds studied, we observed three different behaviors in which the aromatic core is parallel, perpendicular, and tilted with respect to the water surface. We also show that these curved PAHs are able to self-assemble in solution into remarkably large sheets of up to 150 µm2. These results show the relationship, within a family of curved nanographenes, between the monomer configuration and their self-assembly capacity in air/water interfaces and organic-water mixtures.

3.
J Surg Oncol ; 129(8): 1456-1465, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38623064

RESUMEN

BACKGROUND: The reconstructive ladder relies mostly on defect size and depth to determine reconstructive technique, however, in actuality, many more variables ultimately inform reconstructive decision making, especially regarding extremity soft tissue sarcoma (eSTS) defects. The purpose of this study was to describe eSTS patients who will most optimally benefit from an advanced method of reconstruction (defined as a pedicled regional flap or free flap) and to create a simple risk assessment scale that can be employed in clinical practice. STUDY DESIGN: A single-institution retrospective cohort study examined patients undergoing resection of soft tissue sarcoma affecting the upper or lower extremities between 2016 and 2021. We categorized patients who required a pedicled or free flap as having had advanced reconstruction, and all other techniques were considered simple reconstruction. A regression was used to create a risk scale to guide reconstructive decision-making. RESULTS: The following variables were identified as independent predictors of complications and used to create our risk scale: lower extremity tumor location, preoperative radiotherapy, tumor bed excision, male sex, hypertension, and tumor volume. Intermediate and high-risk patients reconstructed using simple techniques had significantly greater overall complication rates compared to those reconstructed with advanced techniques. Major complications were significantly greater in low-risk patients reconstructed with advanced techniques. CONCLUSIONS: To minimize postoperative wound complications, low-risk patients should receive simple methods of reconstruction, whereas high-risk patients should be reconstructed using advanced techniques.


Asunto(s)
Procedimientos de Cirugía Plástica , Complicaciones Posoperatorias , Sarcoma , Humanos , Sarcoma/cirugía , Sarcoma/patología , Masculino , Estudios Retrospectivos , Femenino , Persona de Mediana Edad , Procedimientos de Cirugía Plástica/métodos , Complicaciones Posoperatorias/etiología , Complicaciones Posoperatorias/prevención & control , Anciano , Adulto , Extremidades/cirugía , Extremidades/patología , Medición de Riesgo , Neoplasias de los Tejidos Blandos/cirugía , Neoplasias de los Tejidos Blandos/patología , Toma de Decisiones , Colgajos Quirúrgicos , Estudios de Seguimiento , Toma de Decisiones Clínicas
4.
Ann Plast Surg ; 2024 Jun 24.
Artículo en Inglés | MEDLINE | ID: mdl-38920187

RESUMEN

INTRODUCTION: Soft tissue sarcomas (STSs) are rare and diverse primary malignant tumors that comprise approximately 1% of all malignancies. Misdiagnoses and unplanned excisions of STSs are common due to the tumor's rarity, leading to secondary tumor bed excisions (TBEs). Reconstructive outcomes for TBEs remain poorly understood, prompting this study to address the knowledge gap and inform preoperative discussions. METHODS: This was a retrospective cohort study of patients who underwent STS excisions at a quaternary cancer center. Patients were categorized into mass excision (ME) and TBE groups. Reconstructive approaches were divided into simple (primary closure, complex repair, skin grafts, local flaps) and advanced (pedicled or free flaps). The groups were compared for postoperative outcomes, including complications, recurrence, and death. RESULTS: When simple reconstructive techniques were used, TBEs exhibited higher rates of overall and major complications, whereas MEs had higher rates of overall and minor complications. Intergroup analysis revealed that with simple reconstruction, rates of overall and major complications were higher in TBEs than in MEs, and rates of minor complications were higher in MEs than in TBEs. Regression analyses revealed that simple reconstruction of TBEs had 90% and 180% higher odds of major complications and reoperation compared to simple reconstruction of MEs (P < 0.05). CONCLUSION: TBEs, despite their smaller size, exhibited a heightened susceptibility to overall and major complications, challenging the notion that simpler techniques suffice in these cases. Our findings encourage the consideration of advanced reconstructive techniques for TBEs that may seem amenable to simple reconstructive techniques.

5.
Genet Mol Biol ; 47(1): e20230110, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38488523

RESUMEN

Butyrate is a promising candidate for an antitumoral drug, as it promotes cancer cell apoptosis and reduces hormone receptor activity, while promoting differentiation and proliferation in normal cells. However, the effects of low-dose butyrate on breast cancer cell cultures are unclear. We explored the impact of sub-therapeutic doses of butyrate on estrogen receptor alpha (ERα) transcriptional activity in MCF-7 cells, using RT-qPCR, Western blot, wound-healing assays, and chromatin immunoprecipitation. Our results showed that sub-therapeutic doses of sodium butyrate (0.1 - 0.2 mM) increased the transcription of ESR1, TFF1, and CSTD genes, but did not affect ERα protein levels. Moreover, we observed an increase in cell migration in wound-healing assays. ChIP assays revealed that treatment with 0.1 mM of sodium butyrate resulted in estrogen-independent recruitment of ERα at the pS2 promoter and loss of NCoR. Appropriate therapeutic dosage of butyrate is essential to avoid potential adverse effects on patients' health, especially in the case of estrogen receptor-positive breast tumors. Sub-therapeutic doses of butyrate may induce undesirable cell processes, such as migration due to low-dose butyrate-mediated ERα activation. These findings shed light on the complex effects of butyrate in breast cancer and provide insights for research in the development of antitumoral drugs.

6.
Molecules ; 28(18)2023 Sep 09.
Artículo en Inglés | MEDLINE | ID: mdl-37764323

RESUMEN

In recent years, the determination of the antioxidant and antibacterial activity of essential oils in wild plants, such as Mexican oregano (Lippia graveolens Kunth), has become increasingly important. The objective was to compare the antioxidant and antibacterial activity of Mexican oregano essential oil obtained from plants occurring naturally in semiarid areas (Wild1 and Wild2), and those cultivated in the field (CField) and greenhouse (CGreenhouse) in northern Mexico. The Mexican oregano essential oil extraction was performed using the hydrodistillation method, the antioxidant activity was determined using the ABTS method, and the antibacterial activity was assessed through bioassays under the microwell method at nine different concentrations. The aim was to determine the diameter of the inhibition zone and, consequently, understand the sensitivity level for four bacterial species. The results revealed an antioxidant activity ranging from 90% to 94% at the sampling sites, with Wild1 standing out for having the highest average antioxidant activity values. Likewise, six out of the nine concentrations analyzed showed some degree of sensitivity for all the sampling sites. In this regard, the 25 µL mL-1 concentration showed the highest diameter of inhibition zone values, highlighting the Wild2 site, which showed an average diameter greater than 30 mm for the four bacteria tested. Only in the case of S. typhi did the CGreenhouse site surpass the Wild2, with an average diameter of the inhibition zone of 36.7 mm. These findings contribute to the search for new antioxidant and antibacterial options, addressing the challenges that humanity faces in the quest for opportunities to increase life expectancy.

7.
J Am Chem Soc ; 144(49): 22397-22402, 2022 12 14.
Artículo en Inglés | MEDLINE | ID: mdl-36469014

RESUMEN

Amidines are a structural surrogate for peptide bonds, yet have received considerably little attention in peptides due to limitations in existing methods to access them. The synthetic strategy developed in this study represents the first robust and general procedure for the introduction of amidines into the peptide backbone. We exploit and further develop the utility and efficiency of thioimidate protecting groups as a means to side-step reactivity that ultimately renders existing methods unsuitable for the installation of amidines along the main-chain of peptides. This work is significant because it describes a generally applicable path to access unexplored peptide designs and architectures for new therapeutics made possible by the unique properties of amidines.


Asunto(s)
Amidinas , Péptidos , Amidinas/química , Péptidos/química
8.
Langmuir ; 38(24): 7535-7544, 2022 06 21.
Artículo en Inglés | MEDLINE | ID: mdl-35666568

RESUMEN

Sugar-based amphiphiles are a relevant natural alternative to synthetic ones due to their biodegradable properties. An understanding of their structure-assembly relationship is needed to allow the concrete synthesis of suitable derivatives. Here, four different mannose-derivative surfactants are characterized by pendant drop, dynamic light scattering, small-angle X-ray scattering, cryotransmission electron microscopy, and molecular dynamics techniques in aqueous media. Measurements denote how the polysaccharide average degree of polymerization (DP¯) and the addition of a hydroxyl group to the hydrophobic tail, and thus the presence of a second hydrophilic moiety, affect their self-assembly. A variation in the DP¯ of the amphiphile has no effect in the critical micelle concentration in contrast to a change in the hydrophobic molecular region. Moreover, high-DP¯ amphiphiles self-assemble into spherical micelles irrespective of the hydroxyl group presence. Low-DP¯ amphiphiles with only one hydrophilic moiety form cylindrical micelles, while the addition of a hydroxyl group to the tail leads to a spherical shape.


Asunto(s)
Micelas , Azúcares , Carbohidratos , Interacciones Hidrofóbicas e Hidrofílicas , Tensoactivos/química
9.
Endocr Res ; 47(2): 89-93, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35393913

RESUMEN

BACKGROUND: It has been reported that insulin resistance is related to cognitive decline. The triglycerides and glucose (TyG) index, is a reliable and inexpensive surrogate test for detecting insulin resistance. AIMS: The goal of this study was to evaluate the association between the TyG index and the mild cognitive impairment (MCI) in older adults. METHODS: A total of 135 individuals, men and women aged 60 to 90 years, were enrolled in a case and control study. Individuals with a diagnosis of MCI (n = 65) were allocated into the case group and compared with individuals without MCI (n = 70) in the control group. Alcohol intake, diabetes duration ≥5 years, diagnoses of cerebrovascular disease, brain injury, folic acid deficiency, dementia, moderate or severe CI, major depressive disorders, and thyroid disease were exclusion criteria. RESULTS: Individuals in the case group exhibited higher waist circumference (97.9 ± 13.9 versus 93.5 ± 13.0, p = .001) and TyG index (5.0 ± 0.3 versus 4.1 ± 0.2, p = .001) than individuals in the control group. The TyG index ≥4.68 (OR 6.91; 95% CI 2.05-11.68) and waist circumference (OR 1.03; 95% CI 1.01-1.06) were positively associated with MCI, while education level (OR 0.44; 95% CI 0.30-0.61), occupation (OR 0.75; 95% CI 0.59-0.61), and exercise (OR 0.34; 95% CI 0.22-0.52) were inversely associated with MCI. After controlling for sex, age, waist circumference, education level, occupation, and exercise, a TyG index ≥4.68 remained significantly associated with MCI (OR 2.97; 95% CI 1.12-14.71). CONCLUSION: The TyG index is independently associated with the presence of MCI in older people.


Asunto(s)
Disfunción Cognitiva , Trastorno Depresivo Mayor , Resistencia a la Insulina , Anciano , Biomarcadores , Glucemia , Disfunción Cognitiva/diagnóstico , Femenino , Glucosa , Humanos , Masculino , Factores de Riesgo , Triglicéridos
10.
Biol Lett ; 17(8): 20210316, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-34376075

RESUMEN

Animals may develop mutualistic associations with other species, whereby prey offer resources or services in exchange for protection from predators. Alternatively, prey may offer resources or services directly to their would-be predators in exchange for their lives. The latter may be the case of hemipterans that engage in mutualistic interactions with ants by offering a honeydew reward. We test the extent to which a honeydew offering versus partner recognition may play a role as proximate mechanisms deterring ants from predating upon their hemipteran partners. We showed that, when presented with a choice between a hemipteran partner and an alternative prey type, mutualist ants were less likely to attack and more likely to remain probing their hemipteran partners. This occurred even in the absence of an immediate sugary reward, suggesting either an evolved or learned partner recognition response. To a similar extent, however, ants were also less likely to attack the alternative prey type when laced with honey as a proxy for a honeydew reward. This was the case even after the honey had been depleted, suggesting an ability of ants to recognize new potential sources of sugars. Either possibility suggests a degree of innate or learned partner recognition.


Asunto(s)
Hormigas , Simbiosis , Animales
11.
J Clin Lab Anal ; 35(4): e23712, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33507546

RESUMEN

BACKGROUND: Recurrent respiratory papillomatosis (RRP) is a respiratory tract disease that affects children and adults and is characterized by the recurrent proliferation of multiple papillomas. The etiologic agent is the human papillomavirus, mainly genotypes 6 and 11. Furthermore, polymorphisms in TAP1 appear to influence the selection of antigenic peptides and the transport process to the rough endoplasmic reticulum, for their subsequent presentation to T lymphocytes, an essential process against viral diseases and tumor processes. Previous studies have shown that individuals with those polymorphisms are susceptible to immune, infectious, and tumor-related diseases. The present study aimed to determine the association between the TAP1 rs1057141 (c.1177A>G) and rs1135216 (c.2090A>G) single nucleotide polymorphisms (SNPs) and RRP. METHODS: A case-control study was carried out on a group of 70 individuals (35 controls and 35 patients). RRP diagnosis, HPV genotyping, and viral load were determined through histology and PCR. SNPs rs1057141 and rs1135216 were identified through allelic discrimination, using real-time PCR. The haplotypic analyses were performed using the Arlequin 3.5 program. RESULTS: HPV-6 and HPV-11 were the genotypes found in the samples. In the polymorphism analysis, rs1057141 showed no significant differences (p = 0.049, CI = 0.994-7.331). In contrast, a significant difference was found in rs1135216 (p = 0.039, OR = 2.4) in the allelic analysis, as well as in the dominant (p = 0.027, OR = 3.06), codominant (p = 0.033, OR = 3.06), and additive model (p = 0.043, OR = 2.505) in subjects with the G allele. CONCLUSION: The G allele in rs1135216 was associated with a genetic risk of susceptibility for RRP in a population in Western Mexico.


Asunto(s)
Transportador de Casetes de Unión a ATP, Subfamilia B, Miembro 2/genética , Estudios de Asociación Genética , Predisposición Genética a la Enfermedad , Infecciones por Papillomavirus/genética , Polimorfismo de Nucleótido Simple/genética , Infecciones del Sistema Respiratorio/genética , Adolescente , Adulto , Anciano , Estudios de Casos y Controles , Niño , Preescolar , Femenino , Frecuencia de los Genes/genética , Haplotipos/genética , Humanos , Lactante , Patrón de Herencia/genética , Masculino , México , Persona de Mediana Edad , Modelos Genéticos , Proyectos Piloto , Adulto Joven
12.
Nano Lett ; 20(1): 748-757, 2020 01 08.
Artículo en Inglés | MEDLINE | ID: mdl-31820645

RESUMEN

Material surface topographic features have been shown to be crucial for tissue regeneration and surface treatment of implanted devices. Many biomaterials were investigated with respect to the response of cells on surface roughness. However, some conclusions even conflicted with each other due to the unclear interplay of surface topographic features and substrate elastic features as well as the lack of mechanistic studies. Herein, wide-scale surface roughness gradient hydrogels, integrating the surface roughness from nanoscale to microscale with controllable stiffness, were developed via soft lithography with precise surface morphology. Based on this promising platform, we systematically studied the mechanosensitive response of human mesenchymal stem cells (MSCs) to a broad range of roughnesses (200 nm to 1.2 µm for Rq) and different substrate stiffnesses. We observed that MSCs responded to surface roughness in a stiffness-dependent manner by reorganizing the surface hierarchical structure. Surprisingly, the cellular mechanoresponse and osteogenesis were obviously enhanced on very soft hydrogels (3.8 kPa) with high surface roughness, which was comparable to or even better than that on smooth stiff substrates. These findings extend our understanding of the interactions between cells and biomaterials, highlighting an effective noninvasive approach to regulate stem cell fate via synergetic physical cues.


Asunto(s)
Diferenciación Celular , Hidrogeles/química , Mecanotransducción Celular , Células Madre Mesenquimatosas/metabolismo , Humanos , Células Madre Mesenquimatosas/citología , Propiedades de Superficie
13.
Small ; 16(10): e1905422, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-32064782

RESUMEN

The topographic features of an implant, which mechanically regulate cell behaviors and functions, are critical for the clinical success in tissue regeneration. How cells sense and respond to the topographical cues, e.g., interfacial roughness, is yet to be fully understood and even debatable. Here, the mechanotransduction and fate determination of human mesenchymal stem cells (MSCs) on surface roughness gradients are systematically studied. The broad range of topographical scales and high-throughput imaging is achieved based on a catecholic polyglycerol coating fabricated by a one-step-tilted dip-coating approach. It is revealed that the adhesion of MSCs is biphasically regulated by interfacial roughness. The cell mechanotransduction is investigated from focal adhesion to transcriptional activity, which explains that cellular response to interfacial roughness undergoes a direct force-dependent mechanism. Moreover, the optimized roughness for promoting cell fate specification is explored.


Asunto(s)
Diferenciación Celular , Células Madre Mesenquimatosas , Adhesión Celular , Adhesiones Focales , Humanos , Mecanotransducción Celular/fisiología , Células Madre Mesenquimatosas/citología , Células Madre Mesenquimatosas/metabolismo , Células Madre Mesenquimatosas/ultraestructura , Microscopía Electrónica de Rastreo , Regeneración/fisiología , Propiedades de Superficie
14.
Curr Allergy Asthma Rep ; 20(12): 78, 2020 11 08.
Artículo en Inglés | MEDLINE | ID: mdl-33161494

RESUMEN

PURPOSE OF REVIEW: To study the prevalence of olfactory loss and its associated factors in a Mexican population a cross-sectional analytical study based on a population interviewed about health, epidemiologic aspects, and sense of smell (tested with four scents: rose, banana, perfume, and gas) was conducted to evaluate olfactory detection, memory, and identification. Levels of sense of smell perception were determined when the participants detected, recognized, or identified all (normosmia), 1-3 (hyposmia), or none (anosmia) of the odorants. Associated factors of olfactory dysfunction were identified by multivariate analysis (odds ratio, 95%CI). RECENT FINDINGS: Olfactory dysfunction is a prevalent disorder affecting up to 20% of the general population. In addition to viral infection, including COVID-19, a number of other causes and factors may also be involved. 1,956 surveys were conducted and 1,921 were analyzed. Most of the participants (62.1%) were women. The general prevalence of olfactory dysfunction, regarding detection, was 7.2% (7.1% hyposmia, 0.1% anosmia). Age-related olfactory deterioration was observed in both sexes from the 5th decade of life (OR 2.74, p = 0.0050). Women showed better olfactory identification (OR 0.73, p = 0.0010). Obesity (OR 1.97, p = 0.0070), low educational level, bad/very bad self-perceived olfactory function (OR 2.74, p = 0.0050), olfactory loss for less than one week (OR 1.35, p = 0.0030), exposure to toxics/irritants (OR 1.31, p = 0.0030), active smoking (OR 1.58, p < 0.0010), and type 2 diabetes mellitus (OR 2.68, 95%CI 1.74-4.10, p < 0.0001) were identified as factors associated with olfactory dysfunction. These results in a Mexican population suggest better olfactory identification (verbalization) in females. Age was a determining factor in the olfactory deterioration process and obesity and diabetes mellitus were also associated with olfactory disorders. Finally, these findings reinforce the differential diagnosis with other potential causes of sense of smell loss, during the COVID-19 outbreak.


Asunto(s)
Trastornos del Olfato/epidemiología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Betacoronavirus , COVID-19 , Infecciones por Coronavirus , Estudios Transversales , Femenino , Humanos , Masculino , México/epidemiología , Persona de Mediana Edad , Pandemias , Neumonía Viral , Prevalencia , SARS-CoV-2 , Adulto Joven
15.
Am Nat ; 194(3): 334-343, 2019 09.
Artículo en Inglés | MEDLINE | ID: mdl-31553213

RESUMEN

Predation, which is a fundamental force in ecosystems, has been found to decrease in intensity with elevation and latitude. The mechanisms behind this pattern, however, remain unaddressed. Using visual sampling of potential predators and live flies as baits, we assessed predation patterns along 4,000-m elevation transects on either side of the equatorial Andes. At the lower elevations, we found that around 80% of predation events on our insect baits were due to ants. The decline in predation with elevation was driven mainly by a decline in the abundance of ants, whose importance relative to other predators also declined. We show that both predator density and activity (predation rate per individual predator) decreased with elevation, thus ascribing specific mechanisms to known predation patterns. We suggest that changes in these two mechanisms may reflect changes in primary productivity and metabolic rate with temperature, factors of potential relevance across latitudinal and other macroecological gradients, particularly for ectotherm predators and prey.


Asunto(s)
Altitud , Conducta Predatoria , Animales , Hormigas/fisiología , Artrópodos/fisiología , Dípteros , Ecosistema , Ecuador , Densidad de Población , Vertebrados/fisiología
17.
J Org Chem ; 84(23): 15309-15314, 2019 12 06.
Artículo en Inglés | MEDLINE | ID: mdl-31725287

RESUMEN

Thioamides are important biophysical probes of peptide folding but are prone to α-C epimerization during Fmoc solid-phase peptide synthesis. The stereochemical integrity of thioamide-containing peptides can be dramatically improved by protecting the thioamide as a thioimidate during synthesis. A drawback of this approach, however, is that once synthesis of the peptide is complete, regeneration of the thioamide requires the toxic, corrosive, and flammable gas H2S. This work examines several approaches to supplant H2S as a deprotection reagent in favor of a safer and more convenient alternative. Ultimately, a new application of the 4-azidobenzyl protecting group to thioamides was found to provide the most suitable means of both protection of α-C stereochemistry and conversion back to thioamide.


Asunto(s)
Imidas/química , Péptidos/síntesis química , Técnicas de Síntesis en Fase Sólida , Tioamidas/química , Conformación Molecular , Péptidos/química
18.
Eur Arch Otorhinolaryngol ; 276(2): 357-365, 2019 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-30535977

RESUMEN

PURPOSE: To present a modified method of local infiltration (MMLI) for endoscopic stapes surgery to reduce surgical time, bleeding and complications. MATERIALS AND METHODS: This study involved 70 patients who underwent stapes surgery for otosclerosis by endoscopic and microscopic approaches. The MMLI was applied as follows: local infiltration was performed with one hand while the other hand inserted the endoscope into the ear canal to observe vasoconstriction signs on the monitor; the single site of infiltration was located at the center of the anterior conchal cartilage. Operative time, intraoperative blood loss, preservation of anatomical structures, postoperative hearing and complications were evaluated. RESULTS: The MMLI allowed for quick bleeding control and a clear and dry operative field. Operative time, intraoperative blood loss and preservation of anatomical structures were significantly reduced in the endoscopic group (P < 0.00) versus the microscopic group. The scutum was removed less frequent in the endoscopic group 7.1% versus 53.6% of the microscopic group (P < 0.00). The chorda tympani was preserved in all cases but it was more manipulated in the microscopic group 39.3% versus 9.5% of the endoscopic group (P < 0.00). No complications were observed and the hearing outcomes were significantly better than the preoperative thresholds. CONCLUSIONS: This is the first report on the use of a MMLI for endoscopic stapes surgery. Using this method, the surgeon performs the infiltration at one site and concurrently observes the vasoconstriction signs without the use of a microscope, frontal lamp or speculum. This method provides benefits in terms of operative time and complications.


Asunto(s)
Anestésicos Locales/administración & dosificación , Endoscopía/métodos , Cirugía del Estribo/métodos , Adolescente , Adulto , Pérdida de Sangre Quirúrgica , Endoscopios , Epinefrina/administración & dosificación , Femenino , Humanos , Lidocaína/administración & dosificación , Masculino , Microscopía , Persona de Mediana Edad , Tempo Operativo , Otosclerosis/cirugía , Proyectos Piloto , Complicaciones Posoperatorias , Método Simple Ciego , Adulto Joven
19.
Invest New Drugs ; 36(5): 860-868, 2018 10.
Artículo en Inglés | MEDLINE | ID: mdl-29376210

RESUMEN

Background C-Met, which is frequently activated in multiple cancers, has been implicated in tumor formation, progression, metastasis, angiogenesis, and resistance to multiple therapies. MK-8033 is a small-molecule inhibitor of c-Met that binds preferentially to the activated conformation, and has demonstrated anti-tumor activity in preclinical models. This first-in-human trial was performed to establish the safety and maximum tolerated dose (MTD), as well as preliminary pharmacokinetics (PK) and clinical activity. Methods Forty-seven patients were enrolled in three parts. The primary objective of Parts A and B was safety, whereas Part C evaluated the effect of proton-pump inhibitors on MK-8033 absorption. Dose escalation used an accelerated continual reassessment method, and dose-limiting toxicities (DLTs) were any treatment-related, first course non-hematologic grade ≥ 3 toxicity (except alopecia or inadequately treated nausea/vomiting/diarrhea), grade 4 hematologic toxicity (except grade 3 neutropenic fever and thrombocytopenia), or toxicity where treatment is held >3 weeks. Results Forty-six patients were treated across nine dose levels, and the MTD was 750 mg twice daily. DLTs were fatigue, nausea, vomiting, transaminitis, and hypokalemia. Most frequent toxicities were fatigue (28.3%), nausea (21.7%), and alopecia (19.6%), predominately grade ≤ 2. One patient with endometriod adenocarcinoma achieved a partial response and eight had stable disease. Median progression-free survival (PFS) was 57 days. Strikingly, the PFS for the one responder was 846 days. PK results showed that proton-pump inhibitors have no effect on MK-8033 absorption. Conclusion MK-8033 was well tolerated with no significant toxicity issues, albeit with limited clinical activity. Unfortunately, the company decided to discontinue further clinical development of MK-8033.


Asunto(s)
Antineoplásicos/administración & dosificación , Benzocicloheptenos/administración & dosificación , Neoplasias/tratamiento farmacológico , Proteínas Proto-Oncogénicas c-met/antagonistas & inhibidores , Sulfonamidas/administración & dosificación , Adulto , Anciano , Anciano de 80 o más Años , Antineoplásicos/efectos adversos , Antineoplásicos/sangre , Antineoplásicos/farmacocinética , Benzocicloheptenos/efectos adversos , Benzocicloheptenos/sangre , Benzocicloheptenos/farmacocinética , Femenino , Humanos , Masculino , Dosis Máxima Tolerada , Persona de Mediana Edad , Neoplasias/metabolismo , Supervivencia sin Progresión , Sulfonamidas/efectos adversos , Sulfonamidas/sangre , Sulfonamidas/farmacocinética
20.
Soft Matter ; 14(46): 9343-9350, 2018 Nov 28.
Artículo en Inglés | MEDLINE | ID: mdl-30307451

RESUMEN

Dipeptides self-assemble into supramolecular structures showing plenty of applications in the nanotechnology and biomedical fields. A set of Fmoc-dipeptides with different aminoacid sequences has been synthesized and their self-assembly at fluid interfaces has been assessed. The relevant molecular parameters for achieving an efficient 2D self-assembly process have been established. The self-assembled nanostructures of Fmoc-dipeptides displayed significant chirality and retained the chemical functionality of the aminoacids. The impact of the sequence on the final supramolecular structure has been evaluated in detail using in situ characterization techniques at air/water interfaces. This study provides a general route for the 2D self-assembly of Fmoc-dipeptides.


Asunto(s)
Dipéptidos/química , Fluorenos/química , Aire , Secuencia de Aminoácidos , Agua
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