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1.
Anal Chem ; 95(27): 10211-10220, 2023 07 11.
Artículo en Inglés | MEDLINE | ID: mdl-37364037

RESUMEN

Respiratory infections are common in children, and there is a need for user-friendly collection methods. Here, we performed the first human subjects study using the CandyCollect device, a lollipop-inspired saliva collection device .We showed that the CandyCollect device can be used to collect salivary bacteria from healthy adults using Streptococcus mutans and Staphylococcus aureus as proof-of-concept commensal bacteria. We enrolled healthy adults in a nationwide (USA) remote study in which participants were sent study packages containing CandyCollect devices and traditional commercially available oral swabs and spit tubes. Participants sampled themselves at home, completed usability and user preference surveys, and mailed the samples back to our laboratory for analysis by qPCR. Our results showed that for participants in which a given bacterium (S. mutans or S. aureus) was detected in one or both of the commercially available methods (oral swab and/or spit tubes), CandyCollect devices had a 100% concordance with the positive result (n = 14 participants). Furthermore, the CandyCollect device was ranked the highest preference sampling method among the three sampling methods by 26 participants surveyed (combining survey results across two enrollment groups). We also showed that the CandyCollect device has a shelf life of up to 1 year at room temperature, a storage period that is convenient for clinics or patients to keep the CandyCollect device and use it any time. Taken together, we have demonstrated that the CandyCollect is a user-friendly saliva collection tool that has the potential to be incorporated into diagnostic assays in clinic visits and telemedicine.


Asunto(s)
Saliva , Staphylococcus aureus , Niño , Humanos , Adulto , Saliva/microbiología , Manejo de Especímenes/métodos , Streptococcus mutans , Laboratorios
2.
Microb Cell Fact ; 21(1): 280, 2022 Dec 31.
Artículo en Inglés | MEDLINE | ID: mdl-36587193

RESUMEN

BACKGROUND: Over the 70 years since the introduction of plastic into everyday items, plastic waste has become an increasing problem. With over 360 million tonnes of plastics produced every year, solutions for plastic recycling and plastic waste reduction are sorely needed. Recently, multiple enzymes capable of degrading PET (polyethylene terephthalate) plastic have been identified and engineered. In particular, the enzymes PETase and MHETase from Ideonella sakaiensis depolymerize PET into the two building blocks used for its synthesis, ethylene glycol (EG) and terephthalic acid (TPA). Importantly, EG and TPA can be re-used for PET synthesis allowing complete and sustainable PET recycling. RESULTS: In this study we used Saccharomyces cerevisiae, a species utilized widely in bioindustrial fermentation processes, as a platform to develop a whole-cell catalyst expressing the MHETase enzyme, which converts monohydroxyethyl terephthalate (MHET) into TPA and EG. We assessed six expression architectures and identified those resulting in efficient MHETase expression on the yeast cell surface. We show that the MHETase whole-cell catalyst has activity comparable to recombinant MHETase purified from Escherichia coli. Finally, we demonstrate that surface displayed MHETase is active across a range of pHs, temperatures, and for at least 12 days at room temperature. CONCLUSIONS: We demonstrate the feasibility of using S. cerevisiae as a platform for the expression and surface display of PET degrading enzymes and predict that the whole-cell catalyst will be a viable alternative to protein purification-based approaches for plastic degradation.


Asunto(s)
Hidrolasas , Saccharomyces cerevisiae , Saccharomyces cerevisiae/metabolismo , Hidrolasas/metabolismo , Glicol de Etileno , Plásticos/metabolismo
3.
Artif Organs ; 44(11): E459-E469, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-32530104

RESUMEN

Biocompatibility of ventricular assist devices (VADs) has been steadily improving, yet the rate of neurological events remains unacceptably high. Recent speculation for elevated stroke rates centers on ingestion of thrombi originating upstream of the pump, such as in the ventricle or left atrial appendage. These thrombi may be ejected by the VAD or become deposited within the blood flow pathway, presenting serious complications to the patient. This study was performed to visualize and quantify the degree of disruption, adherence, and disintegration of thrombi that are ingested by the three most implanted VADs: the HeartMate II, HeartMate 3, and HVAD. Clot analogs of varying microstructure compositions (red, white) and sizes (0.5, 1, 2 cm3 ) were synthesized in vitro based on clinical explant data. These were introduced individually into an in vitro flow loop with a transparent replica of the HMII, HM3, and HVAD operated at nominal steady flow (2.3-4.0 L/min). High-speed videography (up to 10 000 fps) revealed the ingestion, disruption, ejection, and adherence of thrombus fragments. Thromboemboli of varying compositions and sizes were observed mechanically attaching to components in all 3 VAD models. In some instances, ingested thrombi physically obstructed portions of the blood flow path; 18% (3 of 17 total) of red thrombi adhered to the inflow straightener of the transparent HMII. In the HVAD model, fewer than 4% of clots were adherent or trapped within the pump, irrespective of microstructure or initial volume. In comparison, 100% (4 of 4 total) of 1-cm3 white (fibrin) clots became lodged within the transparent HM3 while, in contrast, less than 5% of macerated red clots (3 of 63 total) of the same volume were adherent inside the pump. A significant proportion of ingested thrombi were macerated into infinitesimal fragments; 84% and 74% of 2-cm3 red thrombi in the HVAD and HM3 models, respectively, were found to have disintegrated upon ingestion. However, large emboli were also discharged from both centrifugal VADs; these fragments, ranging from 0.01 to 0.29 cm3 regardless of microstructure and original volume, may be capable of occluding an intracranial vessel. Therefore, ingested thrombus may explain, in part, elevated stroke rates in contemporary blood pumps in the absence of adherent pump thrombosis.


Asunto(s)
Corazón Auxiliar/efectos adversos , Trombosis/etiología , Materiales Biocompatibles/efectos adversos , Circulación Sanguínea , Diseño de Equipo , Humanos , Trombosis/fisiopatología
4.
Neurosurg Focus ; 37(4): E16, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25270135

RESUMEN

OBJECT: Swallowing dysfunction is common following transoral (TO) odontoidectomy. Preliminary experience with newer endoscopic transnasal (TN) approaches suggests that dysphagia may be reduced with this alternative. However, the reasons for this are unclear. The authors hypothesized that the TN approach results in less disruption of the pharyngeal plexus and anatomical structures associated with swallowing. The authors investigate the histological and gross surgical anatomical relationship between pharyngeal plexus innervation of the upper aerodigestive tract and the surgical approaches used (TN and TO). They also review the TN literature to evaluate swallowing outcomes following this approach. METHODS: Seven cadaveric specimens were used for histological (n = 3) and gross anatomical (n = 4) examination of the pharyngeal plexus with the TO and TN surgical approaches. Particular attention was given to identifying the location of cranial nerves (CNs) IX and X and the sympathetic chain and their contributions to the pharyngeal plexus. S100 staining was performed to assess for the presence of neural tissue in proximity to the midline, and fiber density counts were performed within 1 cm of midline. The relationship between the pharyngeal plexus, clivus, and upper cervical spine (C1-3) was defined. RESULTS: Histological analysis revealed the presence of pharyngeal plexus fibers in the midline and a significant reduction in paramedian fiber density from C-2 to the lower clivus (p < 0.001). None of these paramedian fibers, however, could be visualized with gross inspection or layer-by-layer dissection. Laterally based primary pharyngeal plexus nerves were identified by tracing their origins from CNs IX and X and the sympathetic chain at the skull base and following them to the pharyngeal musculature. In addition, the authors found 15 studies presenting 52 patients undergoing TN odontoidectomy. Of these patients, only 48 had been swallowing preoperatively. When looking only at this population, 83% (40 of 48) were swallowing by Day 3 and 92% (44 of 48) were swallowing by Day 7. CONCLUSIONS: Despite the midline approach, both TO and TN approaches may injure a portion of the pharyngeal plexus. By limiting the TN incision to above the palatal plane, the surgeon avoids the high-density neural plexus found in the oropharyngeal wall and limits injury to oropharyngeal musculature involved in swallowing. This may explain the decreased incidence of postoperative dysphagia seen in TN approaches. However, further clinical investigation is warranted.


Asunto(s)
Deglución/fisiología , Endoscopía/métodos , Nariz/cirugía , Apófisis Odontoides/cirugía , Análisis de Varianza , Cadáver , Femenino , Nervio Glosofaríngeo/metabolismo , Nervio Glosofaríngeo/cirugía , Humanos , Masculino , Proteínas S100/metabolismo
5.
Molecules ; 19(5): 6754-75, 2014 May 23.
Artículo en Inglés | MEDLINE | ID: mdl-24858266

RESUMEN

The preparation of gold nanoparticles (AuNPs) of high purity and stability remains a major challenge for biological applications. This paper reports a simple synthetic strategy to prepare water-soluble peptide-stabilized AuNPs. Reduced glutathione, a natural tripeptide, was used as a synthon for the growth of two peptide chains directly on the AuNP surface. Both nonpolar (tryptophan and methionine) and polar basic (histidine and dansylated arginine) amino acids were conjugated to the GSH-capped AuNPs. Ultracentrifugation concentrators with polyethersulfone (PES) membranes were used to purify precursor materials in each stage of the multi-step synthesis to minimize side reactions. Thin layer chromatography, transmission electron microscopy, UV-Visible, 1H-NMR, and fluorescence spectroscopies demonstrated that ultracentrifugation produces high purity AuNPs, with narrow polydispersity, and minimal aggregation. More importantly, it allows for more control over the composition of the final ligand structure. Studies under conditions of varying pH and ionic strength revealed that peptide length, charge, and hydrophobicity influence the stability as well as solubility of the peptide-capped AuNPs. The synthetic and purification strategies used provide a facile route for developing a library of tailored biocompatible peptide-stabilized AuNPs for biomedical applications.


Asunto(s)
Glutatión/química , Nanopartículas del Metal/química , Sitios de Unión , Oro/química , Espectroscopía de Resonancia Magnética , Microscopía Electrónica de Transmisión , Polímeros/química , Solubilidad , Espectrometría de Fluorescencia , Espectroscopía Infrarroja por Transformada de Fourier , Sulfonas/química , Ultracentrifugación , Agua
6.
Aesthet Surg J ; 34(6): 884-94, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-24938778

RESUMEN

Although primary breast lymphomas are exceedingly rare, cases of breast implant-associated anaplastic large cell lymphoma (iALCL) continue to be reported. The authors describe their experience with 2 patients and review the literature. Both patients presented with periprosthetic fluid collection. Neither had evidence of systemic disease nor received systemic therapy. Both were disease free after bilateral capsulectomies and implant removal without implant replacement, and disease did not recur. During the literature review, 63 cases of iALCL (including our 2 patients) were identified. The median time from implant placement to diagnosis was 9 years. Both saline and silicone implants were associated with iALCL. Of the 26 cases for which implant surface was reported, the surface was textured in 24. Of the 58 patients with an identifiable presentation, 39 had periprosthetic fluid collection, including 7 with an associated mass; 13 had an isolated mass at presentation, including 1 with axillary adenopathy. Forty patients had capsulectomy, 7 of whom underwent implant replacement. Of the 44 patients with known treatment, 33 received chemotherapy and 23 received radiation. Of the 49 patients with known anaplastic large cell lymphoma, 15 had disease recurrence, and 4 patient deaths were reported. Of the 18 patients presenting with a mass, 11 had disease recurrence, including all 4 patients who died. This study represents the largest review of patients with iALCL described to date. Although most cases have an indolent clinical course, the variety of presentations defined as "seroma" vs "capsular involvement" emphasizes the importance of investigating a definitive method of diagnosis, management, and treatment of this disease. LEVEL OF EVIDENCE 5.


Asunto(s)
Implantación de Mama/efectos adversos , Implantes de Mama/efectos adversos , Neoplasias de la Mama/etiología , Linfoma Anaplásico de Células Grandes/etiología , Siliconas/efectos adversos , Cloruro de Sodio/efectos adversos , Adulto , Anciano , Anciano de 80 o más Años , Biopsia , Implantación de Mama/instrumentación , Neoplasias de la Mama/diagnóstico por imagen , Neoplasias de la Mama/cirugía , Remoción de Dispositivos , Femenino , Humanos , Linfoma Anaplásico de Células Grandes/diagnóstico por imagen , Linfoma Anaplásico de Células Grandes/cirugía , Imagen por Resonancia Magnética , Persona de Mediana Edad , Diseño de Prótesis , Factores de Riesgo , Resultado del Tratamiento , Ultrasonografía Mamaria , Adulto Joven
8.
Lab Chip ; 22(18): 3555-3564, 2022 09 13.
Artículo en Inglés | MEDLINE | ID: mdl-35983761

RESUMEN

Streptococcus pyogenes is a major human-specific bacterial pathogen and a common cause of a wide range of symptoms from mild infection such as pharyngitis (commonly called strep throat) to life-threatening invasive infection and post-infectious sequelae. Traditional methods for diagnosis include collecting a sample using a pharyngeal swab, which can cause discomfort and even discourage adults and children from seeking proper testing and treatment in the clinic. Saliva samples are an alternative to pharyngeal swabs. To improve the testing experience for strep throat, we developed a novel lollipop-inspired sampling platform (called CandyCollect) to capture bacteria in saliva. The device can be used in clinics or in the home and shipped back to a lab for analysis, integrating with telemedicine. CandyCollect is designed to capture bacteria on an oxygen plasma treated polystyrene surface embedded with flavoring substances to enhance the experience for children and inform the required time to complete the sampling process. In addition, the open channel structure prevents the tongue from scraping and removing the captured bacteria. The flavoring substances did not affect bacterial capture and the device has a shelf life of at least 2 months (with experiments ongoing to extend the shelf life). We performed a usability study with 17 participants who provided feedback on the device design and the dissolving time of the candy. This technology and advanced processing techniques, including polymerase chain reaction (PCR), will enable user-friendly and effective diagnosis of streptococcal pharyngitis.


Asunto(s)
Faringitis , Infecciones Estreptocócicas , Adulto , Niño , Humanos , Faringitis/diagnóstico , Faringitis/microbiología , Reacción en Cadena de la Polimerasa , Saliva , Infecciones Estreptocócicas/diagnóstico , Infecciones Estreptocócicas/microbiología , Streptococcus pyogenes/genética
9.
Can J Neurol Sci ; 38(1): 72-7, 2011 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-21156433

RESUMEN

OBJECTIVE: The maintenance of post-operative lordosis has been shown to be a key factor in decreasing adjacent level disc stress. Previous studies of the PEEK (polyether ketone) cage have used intervertebral bony fusion as the primary measure of surgical success; however, little is known about its effects on spinal curvature. Our objective was to compare the PEEK cage to the cervical plate with respect to the maintenance of cervical lordosis at one year. Secondary outcomes included fusion and complication rates. METHODS: We performed a retrospective study of patients who underwent ACDF (anterior cervical discectomy and fusion) by two different methods; 13 patients were treated with the PEEK cage, and 22 with allograft and plating. RESULTS: Patient and treatment characteristics were similar in both groups. Average global lordotic curvature (C2-C7) was increased by 1.7 degrees for the PEEK cage and decreased by 1.6 degrees for the plate after an average follow-up of 12.46 and 14.95 months, respectively. Regional lordosis for the PEEK cage and plate was decreased by 2.5 and 2.1 degrees, respectively for the same time period. These differences did not achieve statistical significance. Bony fusion was observed in all patients. One patient in each group developed persistent mild dysphagia. CONCLUSIONS: The PEEK cage is comparable to the anterior cervical plate in the maintenance of post-operative cervical lordosis.


Asunto(s)
Materiales Biocompatibles/uso terapéutico , Placas Óseas , Discectomía , Cetonas/uso terapéutico , Lordosis/cirugía , Polietilenglicoles/uso terapéutico , Fusión Vertebral , Adulto , Anciano , Benzofenonas , Vértebras Cervicales/patología , Vértebras Cervicales/cirugía , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Polímeros , Estudios Retrospectivos , Índice de Severidad de la Enfermedad , Estadísticas no Paramétricas , Resultado del Tratamiento
10.
J Oral Maxillofac Surg ; 68(11): 2824-32, 2010 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-20828910

RESUMEN

PURPOSE: The concept of virtual surgery uses surgical simulation rather than relying exclusively on intraoperative manual approximation of facial reconstruction. The purpose of this study was to evaluate the degree to which surgical outcomes in free fibula mandibular reconstructions planned with virtual surgery and carried out with prefabricated surgical plate templates and cutting guides correlated to the virtual surgical plan in a series of 11 patients. MATERIALS AND METHODS: This retrospective study evaluated 11 consecutive patients (6 males and 5 females) with an average age of 50.73 years (range, 23-72 years) who required mandibular reconstruction for aggressive benign or malignant disease with a free fibula osseomyocutaneous flap at Emory University Hospital (Atlanta, GA) between January 1, 2009 and December 31, 2009. In each case, a high-resolution helical computed tomography (CT) scan of the maxillofacial region and mandible was obtained prior to surgery. The CT data was sent on a CD to a modeling company (Medical Modeling Inc, Golden, CO). The scans were then converted into 3-dimensional models of the maxillofacial skeleton utilizing both automatic and manual segmentation techniques in the SurgiCase CMF software (Materialise NV, Leuven, Belgium). A virtual surgery planning session was held via a Web meeting between the surgeons and the modeling company, at which the resection planes of the mandible, positioning of the plate, and fibula lengths/osteotomy angles were established. The surgery was then carried out using prefabricated cutting guides and manual bending of a reconstruction plate using a prefabricated plate template. A postoperative CT scan of each patient was obtained within the first 7 postoperative days on the same scanner. Three-dimensional computer models of the final reconstruction were obtained for comparison with the preoperative virtual plan. To make the desired comparisons, the 3-dimensional objects representing the postoperative surgical outcome were superimposed onto the preoperative virtual plan using manual alignment techniques. These objects were then compared by 1-to-1 magnification for measurements of fibular bone volume, location of mandibular osteotomies, location of fibular osteotomies, plate contour, plate position on fibula, and plate position on mandible. Comparison was made between the virtual and final plates with regard to contour and position through superimposition overlays of the 3-dimensional models that are registered in the same coordinate system. RESULTS: A total of 19 mandibular osteotomies were carried out. The mean distance of the actual mandibular osteotomy when compared to the virtual mandibular osteotomy was 2.00 ± 1.12 mm. The mean volume determined by the software program of the 11 virtual fibulas was 13,669.45 ± 3,874.15 mm(3) (range, 9,568 to 22,860 mm(3)), and the mean volume of the 11 actual postoperative fibulas was 12,361.09 ± 4,161.80 mm(3) (range, 7,142 to 22,294 mm(3)). The mean percentage volumes of the actual postoperative fibula compared to the planned fibula were 90.93 ± 18.03%. A total of 22 fibular segments were involved in the study created by 44 separate fibula osteotomies. The mean distance of the actual fibula osteotomy when compared to the virtual fibula osteotomy was 1.30 ± 0.59 mm. The mean percentage overlap of the actual plate to the virtual plate was 58.73% ± 8.96%. CONCLUSIONS: Virtual surgical planning appears to have a positive impact on the reconstruction of major mandibular defects through the provision of accuracy difficult to achieve through manual placement of the graft, even in the hands of experienced surgeons. Although a reasonably high level of accuracy was achieved in the mandibular and fibula osteotomies through use of the surgical cutting guides, the limited ability to correctly contour the plate by hand to replicate the plate template is reflected in our findings.


Asunto(s)
Trasplante Óseo/métodos , Mandíbula/cirugía , Planificación de Atención al Paciente , Procedimientos de Cirugía Plástica/métodos , Interfaz Usuario-Computador , Adulto , Anciano , Placas Óseas , Trasplante Óseo/estadística & datos numéricos , Femenino , Peroné/patología , Peroné/cirugía , Estudios de Seguimiento , Humanos , Imagenología Tridimensional , Masculino , Mandíbula/patología , Neoplasias Mandibulares/cirugía , Persona de Mediana Edad , Modelos Anatómicos , Músculo Esquelético/trasplante , Tamaño de los Órganos , Osteotomía/métodos , Osteotomía/estadística & datos numéricos , Planificación de Atención al Paciente/estadística & datos numéricos , Procedimientos de Cirugía Plástica/estadística & datos numéricos , Estudios Retrospectivos , Trasplante de Piel/métodos , Programas Informáticos , Colgajos Quirúrgicos , Recolección de Tejidos y Órganos/métodos , Recolección de Tejidos y Órganos/estadística & datos numéricos , Tomografía Computarizada Espiral , Resultado del Tratamiento , Adulto Joven
12.
Int J Nanomedicine ; 15: 4091-4104, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32606666

RESUMEN

INTRODUCTION: Humans are intentionally exposed to gold nanoparticles (AuNPs) where they are used in variety of biomedical applications as imaging and drug delivery agents as well as diagnostic and therapeutic agents currently in clinic and in a variety of upcoming clinical trials. Consequently, it is critical that we gain a better understanding of how physiochemical properties such as size, shape, and surface chemistry drive cellular uptake and AuNP toxicity in vivo. Understanding and being able to manipulate these physiochemical properties will allow for the production of safer and more efficacious use of AuNPs in biomedical applications. METHODS AND MATERIALS: Here, AuNPs of three sizes, 5 nm, 10 nm, and 20 nm, were coated with a lipid bilayer composed of sodium oleate, hydrogenated phosphatidylcholine, and hexanethiol. To understand how the physical features of AuNPs influence uptake through cellular membranes, sum frequency generation (SFG) was utilized to assess the interactions of the AuNPs with a biomimetic lipid monolayer composed of a deuterated phospholipid 1.2-dipalmitoyl-d62-sn-glycero-3-phosphocholine (dDPPC). RESULTS AND DISCUSSION: SFG measurements showed that 5 nm and 10 nm AuNPs are able to phase into the lipid monolayer with very little energetic cost, whereas, the 20 nm AuNPs warped the membrane conforming it to the curvature of hybrid lipid-coated AuNPs. Toxicity of the AuNPs were assessed in vivo to determine how AuNP curvature and uptake influence cell health. In contrast, in vivo toxicity tested in embryonic zebrafish showed rapid toxicity of the 5 nm AuNPs, with significant 24 hpf mortality occurring at concentrations ≥20 mg/L, whereas the 10 nm and 20 nm AuNPs showed no significant mortality throughout the five-day experiment. CONCLUSION: By combining information from membrane models using SFG spectroscopy with in vivo toxicity studies, a better mechanistic understanding of how nanoparticles (NPs) interact with membranes is developed to understand how the physiochemical features of AuNPs drive nanoparticle-membrane interactions, cellular uptake, and toxicity.


Asunto(s)
Membrana Celular/química , Oro/toxicidad , Lípidos/química , Membranas Artificiales , Nanopartículas del Metal/toxicidad , Tamaño de la Partícula , Pruebas de Toxicidad , Animales , Embrión no Mamífero/anomalías , Embrión no Mamífero/efectos de los fármacos , Humanos , Espectrofotometría Ultravioleta , Análisis Espectral , Pez Cebra/embriología
13.
Genome Med ; 11(1): 54, 2019 08 23.
Artículo en Inglés | MEDLINE | ID: mdl-31443728

RESUMEN

BACKGROUND: DNA methylation changes with age. Chronological age predictors built from DNA methylation are termed 'epigenetic clocks'. The deviation of predicted age from the actual age ('age acceleration residual', AAR) has been reported to be associated with death. However, it is currently unclear how a better prediction of chronological age affects such association. METHODS: In this study, we build multiple predictors based on training DNA methylation samples selected from 13,661 samples (13,402 from blood and 259 from saliva). We use the Lothian Birth Cohorts of 1921 (LBC1921) and 1936 (LBC1936) to examine whether the association between AAR (from these predictors) and death is affected by (1) improving prediction accuracy of an age predictor as its training sample size increases (from 335 to 12,710) and (2) additionally correcting for confounders (i.e., cellular compositions). In addition, we investigated the performance of our predictor in non-blood tissues. RESULTS: We found that in principle, a near-perfect age predictor could be developed when the training sample size is sufficiently large. The association between AAR and mortality attenuates as prediction accuracy increases. AAR from our best predictor (based on Elastic Net, https://github.com/qzhang314/DNAm-based-age-predictor ) exhibits no association with mortality in both LBC1921 (hazard ratio = 1.08, 95% CI 0.91-1.27) and LBC1936 (hazard ratio = 1.00, 95% CI 0.79-1.28). Predictors based on small sample size are prone to confounding by cellular compositions relative to those from large sample size. We observed comparable performance of our predictor in non-blood tissues with a multi-tissue-based predictor. CONCLUSIONS: This study indicates that the epigenetic clock can be improved by increasing the training sample size and that its association with mortality attenuates with increased prediction of chronological age.


Asunto(s)
Envejecimiento/genética , Metilación de ADN , Epigénesis Genética , Epigenómica/métodos , Predisposición Genética a la Enfermedad , Estudio de Asociación del Genoma Completo , Humanos , Especificidad de Órganos/genética , Modelos de Riesgos Proporcionales , Reproducibilidad de los Resultados , Saliva
14.
World Neurosurg ; 110: e484-e489, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-29155062

RESUMEN

BACKGROUND: Type II odontoid fracture is a highly morbid injury among octogenarians, with 41% 1-year mortality. Our objective was to assess long-term fusion, complication, and survival rates. METHODS: Retrospective review of prospective trauma registry and blinded review of follow-up radiographs. RESULTS: Follow-up cohort included 94 nonoperative and 17 operative patients (median, 52 and 79 months). The operative group had significantly higher rates of repeated surgery for primary treatment failure or complication (1% vs. 18%; P = 0.01) and dysphagia, aspiration events, or tracheostomy (29% vs. 78%, P = 0.002; 6% vs. 30%, P = 0.04; 1% vs. 18%, P = 0.01). Three-year all-cause mortalities were 71% and 76%, respectively (P = 0.78). No delayed myelopathy was observed. One-year postinjury radiographs were available for 13 and 6 patients in the nonoperative and operative groups (P = 0.9); bony union was observed in 3 and 5 patients (23% vs. 83%; P = 0.04). Retrolisthesis greater than 2 mm was observed in 2 and 1 patients (15% vs. 17%; P = 1.0). Two patients in the operative group underwent repeated surgery for primary treatment failure. Dysphagia was diagnosed in 3 and 5 operative patients (23% vs. 83%; P = 0.04), whereas aspiration events occurred in 0 and 3 patients (0% vs. 50%; P = 0.02). Three-year mortalities in this cohort were 38% and 67% (P = 0.35). CONCLUSIONS: Radiographic union is significantly associated with operative management, but the corresponding clinical benefit is unclear. Complications were significantly more common after surgery. Long-term survival in octogenarians following type II odontoid fracture is poor, independent of management. Frequent complications without a proven survival benefit suggest that most patients are better managed conservatively.


Asunto(s)
Apófisis Odontoides/lesiones , Fracturas de la Columna Vertebral/mortalidad , Fracturas de la Columna Vertebral/terapia , Anciano de 80 o más Años , Trastornos de Deglución/mortalidad , Femenino , Estudios de Seguimiento , Humanos , Estimación de Kaplan-Meier , Masculino , Apófisis Odontoides/diagnóstico por imagen , Apófisis Odontoides/cirugía , Complicaciones Posoperatorias/mortalidad , Estudios Prospectivos , Fracturas de la Columna Vertebral/diagnóstico por imagen , Resultado del Tratamiento
15.
J Neurosurg Spine ; 26(1): 4-9, 2017 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-27541846

RESUMEN

OBJECTIVE Type II odontoid fracture is a common injury among elderly patients, particularly given their predisposition toward low-energy falls. Previous studies have demonstrated a survival advantage following early surgery among patients older than 65 years, yet octogenarians represent a medically distinct and rapidly growing population. The authors compared operative and nonoperative management in patients older than 79 years. METHODS A single-center prospectively maintained trauma database was reviewed using ICD-9 codes to identify octogenarians with C-2 cervical fractures between 1998 and 2014. Cervical CT images were independently reviewed by blinded neurosurgeons to confirm a Type II fracture pattern. Prospectively recorded outcomes included Glasgow Coma Scale (GCS) score, Abbreviated Injury Scale (AIS) score, Injury Severity Score (ISS), additional cervical fracture, and cord injury. Primary end points were mortality at 30 days and at 1 year. Statistical tests included the Student t-test, chi-square test, Fisher's exact test, Kaplan-Meier test, and Cox proportional hazard. RESULTS A total of 111 patients met inclusion criteria (94 nonoperative and 17 operative [15 posterior and 2 anterior]). Mortality data were available for 100% of patients. The mean age was 87 years (range 80-104 years). Additional cervical fracture, spinal cord injury, GCS score, AIS score, and ISS were not associated with either management strategy at the time of presentation. The mean time to death or last follow-up was 22 months (range 0-129 months) and was nonsignificant between operative and nonoperative groups (p = 0.3). Overall mortality was 13% in-hospital, 26% at 30 days, and 41% at 1 year. Nonoperative and operative mortality rates were not significant at any time point (12% vs 18%, p = 0.5 [in-hospital]; 27% vs 24%, p = 0.8 [30-day]; and 41% vs 41%, p = 1.0 [1-year]). Kaplan-Meier analysis did not demonstrate a survival advantage for either management strategy. Spinal cord injury, GCS score, AIS score, and ISS were significantly associated with 30-day and 1-year mortality; however, Cox modeling was not significant for any variable. Additional cervical fracture was not associated with increased mortality. The rate of nonhome disposition was not significant between the groups. CONCLUSIONS Type II odontoid fracture is associated with high morbidity among octogenarians, with 41% 1-year mortality independent of intervention-a dramatic decrease from actuarial survival rates for all 80-, 90-, and 100-year-old Americans. Poor outcome is associated with spinal cord injury, GCS score, AIS score, and ISS.


Asunto(s)
Apófisis Odontoides/lesiones , Fracturas de la Columna Vertebral/terapia , Accidentes por Caídas/mortalidad , Anciano de 80 o más Años , Femenino , Estudios de Seguimiento , Escala de Coma de Glasgow , Humanos , Puntaje de Gravedad del Traumatismo , Estimación de Kaplan-Meier , Masculino , Apófisis Odontoides/diagnóstico por imagen , Apófisis Odontoides/cirugía , Estudios Prospectivos , Traumatismos de la Médula Espinal/complicaciones , Traumatismos de la Médula Espinal/diagnóstico por imagen , Traumatismos de la Médula Espinal/mortalidad , Fracturas de la Columna Vertebral/complicaciones , Fracturas de la Columna Vertebral/diagnóstico por imagen , Fracturas de la Columna Vertebral/mortalidad , Tomografía Computarizada por Rayos X
16.
J Neuropathol Exp Neurol ; 75(4): 334-46, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26921370

RESUMEN

Mutations in peripheral myelin protein 22 (PMP22) result in the most common form of Charcot-Marie-Tooth (CMT) disease, CMT1A. This hereditary peripheral neuropathy is characterized by dysmyelination of peripheral nerves, reduced nerve conduction velocity, and muscle weakness. APMP22 point mutation in L16P (leucine 16 to proline) underlies a form of human CMT1A as well as the Trembler-J mouse model of CMT1A. Homozygote Trembler-J mice (Tr(J)) die early postnatally, fail to make peripheral myelin, and, therefore, are more similar to patients with congenital hypomyelinating neuropathy than those with CMT1A. Because recent studies of inherited neuropathies in humans and mice have demonstrated that dysfunction and degeneration of neuromuscular synapses or junctions (NMJs) often precede impairments in axonal conduction, we examined the structure and function of NMJs in Tr(J)mice. Although synapses appeared to be normally innervated even in end-stage Tr(J)mice, the growth and maturation of the NMJs were altered. In addition, the amplitudes of nerve-evoked muscle endplate potentials were reduced and there was transmission failure during sustained nerve stimulation. These results suggest that the severe congenital hypomyelinating neuropathy that characterizes Tr(J)mice results in structural and functional deficits of the developing NMJ.


Asunto(s)
Enfermedad de Charcot-Marie-Tooth/genética , Enfermedad de Charcot-Marie-Tooth/patología , Modelos Animales de Enfermedad , Proteínas de la Mielina/genética , Enfermedades de la Unión Neuromuscular/etiología , Enfermedades de la Unión Neuromuscular/patología , Animales , Animales Recién Nacidos , Diafragma/patología , Diafragma/ultraestructura , Estimulación Eléctrica , Potenciales Evocados/genética , Homocigoto , Humanos , Ratones , Ratones Endogámicos BALB C , Ratones Transgénicos , Microscopía Electrónica , Conducción Nerviosa/genética , Unión Neuromuscular/patología , Unión Neuromuscular/ultraestructura , Enfermedades de la Unión Neuromuscular/genética , Mutación Puntual/genética
17.
J Neurosurg Spine ; 24(4): 521-6, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26654341

RESUMEN

OBJECT: Endoscopic approaches to the anterior craniocervical junction are increasing in frequency. Choice of oral versus endoscopic endonasal approach to the odontoid often depends on the relationship of the C1-2 complex to the hard palate. However, it is not known how this relevant anatomy changes with age. We hypothesize that there is a dynamic relationship of C-2 and the hard palate, which changes with age, and potentially affects the choice of surgical approach. The aim of this study was to characterize the relationship of C-2 relative to the hard palate with respect to age and sex. METHODS: Emergency department billing and trauma records from 2008 to 2014 were reviewed for patients of all ages who underwent cervical or maxillofacial CT as part of a trauma evaluation for closed head injury. Patients who had a CT scan that allowed adequate visualization of the hard palate, opisthion, and upper cervical spine (C-1 and C-2) were included. Patients who had cervical or displaced facial/skull base fractures, a history of rheumatoid arthritis, or craniofacial anomalies were excluded. The distance from McGregor's palatooccipital line to the midpoint of the inferior endplate of C-2 (McL-C2) was measured on midsagittal CT scans. Patients were grouped by decile of age and by sex. A 1-way ANOVA was performed with each respective grouping. RESULTS: Ultimately, 483 patients (29% female) were included. The mean age was 46 ± 24 years. The majority of patients studied were in the 2nd through 8th decades of life (85%). Significant variation was found between McL-C2 and decile of age (p < 0.001) and sex (p < 0.001). The mean McL-C2 was 27 mm in the 1st decade of life compared with the population mean of 37 mm. The mean McL-C2 was also noted to be smaller in females (mean difference 4.8 mm, p < 0.0001). Both decile of age (p = 0.0009) and sex (p < 0.0001) were independently correlated with McL-C2 on multivariate analysis. CONCLUSIONS: The relationship of C-2 and the hard palate significantly varies with respect to age and sex, descending relative to the hard palate a full centimeter on average in adulthood. These findings may have relevance in determining optimal surgical approaches for addressing pathology involving the anterior craniocervical junction.


Asunto(s)
Articulación Atlantoaxoidea/cirugía , Vértebras Cervicales/cirugía , Cuello/cirugía , Procedimientos Neuroquirúrgicos , Apófisis Odontoides/cirugía , Paladar Duro/cirugía , Adulto , Factores de Edad , Anciano , Descompresión Quirúrgica/métodos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Procedimientos Neuroquirúrgicos/métodos , Factores Sexuales , Tomografía Computarizada por Rayos X/métodos , Resultado del Tratamiento , Adulto Joven
18.
J Periodontol ; 86(2): 222-31, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25299390

RESUMEN

BACKGROUND: This study examines: 1) alveolar bone loss (ABL), a hallmark of periodontitis, in anti-citrullinated protein antibody (ACPA)-positive rheumatoid arthritis (RA) patients versus control patients with osteoarthritis (OA); and 2) the association of ABL with RA disease activity and ACPA concentrations, including multiple antigen-specific ACPA. METHODS: This multicenter case-control study includes 617 patients diagnosed with RA (n = 287) or OA (n = 330). Panoramic radiographs were taken; patients were categorized into low, moderate, or high tertiles based on mean percentage ABL. Serum ACPA was measured using second-generation anticyclic citrullinated peptide enzyme-linked immunosorbent assay and a multiplex platform to assess distinct antigen-specific ACPA. A generalized linear mixed model for binary data was used to compare stratified ABL in RA versus OA patients. Associations of moderate and high ABL (versus low) with RA disease activity and severity measures were examined using multivariate regression. Antigen-specific ACPA responses were compared among ABL tertiles using significance analysis of microarrays. RESULTS: ACPA-positive patients with RA had a significantly higher mean percentage of sites with ABL >20% compared with patients with OA (P = 0.03). After multivariate adjustment, greater ABL was significantly associated with higher serum ACPA concentration (P = 0.004), 28-joint Disease Activity Score (P = 0.023), health assessment questionnaire disability (P = 0.05), tender joint count (P = 0.02) and joint space narrowing scores (P = 0.05) among patients with RA. ACPAs targeting citrullinated vimentin and histone were significantly higher in moderate and high ABL groups versus low, regardless of smoking status (q <0.1%). CONCLUSIONS: Greater ABL was associated with higher ACPA, consistent with findings at articular sites. ACPA targeting could provide novel insight into important linkages between RA and periodontitis.


Asunto(s)
Pérdida de Hueso Alveolar/inmunología , Artritis Reumatoide/sangre , Autoanticuerpos/sangre , Péptidos Cíclicos/sangre , Anciano , Artritis Reumatoide/diagnóstico por imagen , Artritis Reumatoide/inmunología , Autoantígenos/sangre , Proteína C-Reactiva/análisis , Estudios de Casos y Controles , Progresión de la Enfermedad , Femenino , Cadenas HLA-DRB1/sangre , Articulaciones de la Mano/diagnóstico por imagen , Histonas/sangre , Humanos , Masculino , Persona de Mediana Edad , Osteoartritis/sangre , Osteoartritis/diagnóstico por imagen , Osteoartritis/inmunología , Péptidos Cíclicos/inmunología , Radiografía , Factor Reumatoide/sangre , Fumar/inmunología , Vimentina/sangre , Articulación de la Muñeca/diagnóstico por imagen
19.
Int J Radiat Oncol Biol Phys ; 45(1): 21-32, 1999 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-10477002

RESUMEN

PURPOSE: To report the initial experience in the definitive treatment of head and neck carcinomas using SMART (Simultaneous Modulated Accelerated Radiation Therapy) boost technique. Radiation was delivered via IMRT (Intensity Modulated Radiotherapy). The following parameters were evaluated: acute toxicity, initial tumor response, clinical feasibility, dosimetry and cost. METHODS AND MATERIALS: Between January 1996 and December 1997, 20 patients with primary head and neck carcinomas were treated with SMART boost technique. The treatment fields encompassed two simultaneous targets. The primary target included palpable and visible disease sites. The secondary target included regions at risk for microscopic disease. Daily fractions of 2.4 Gy and 2 Gy were prescribed and delivered to the primary and secondary targets to a total dose of 60 Gy and 50 Gy, respectively. Lower neck nodes were treated with a single conventional anterior portal. This fractionation schedule was completed in 5 weeks with 5 daily fractions weekly. Toxicity was evaluated by RTOG acute toxicity grading criteria, evidence of infection at immobilization screw sites, subjective salivary function, weight loss, and the need for treatment split. Mean follow-up was 15.2 months. Initial tumor response was assessed by clinical and radiographical examinations. Clinical feasibility was evaluated by the criteria: time to treat patient, immobilization, and treatment planning and QA time. In dosimetry, we evaluated the mean doses of both targets and normal tissues and percent targets' volume below goal. To evaluate cost, Medicare allowable charge for SMART boost was compared to those of conventional fractionated and accelerated radiotherapy. RESULTS: ACUTE TOXICITY: None of the patients had a screw site infection and all patients healed well after completion of radiotherapy. Sixteen of 20 patients (80%) completed the treatment within 40 days without any split. Sixteen patients (80%) had RTOG Grade 3 mucositis while 10 patients (50%) had Grade 3 pharyngitis. Three of 20 patients (15%) had weight loss greater than 10% of their pretreatment weight. Ten patients (50%) required intravenous fluids, tube feeding or both. Nine patients (45%) reported moderate xerostomia with significant relief reported within 6 months. INITIAL TUMOR RESPONSE: 19 patients (95 %) had complete response (CR) while one had partial response (PR). The patient with PR had stable disease on imaging at 12 months follow-up. Two patients were found to have lung metastases at 2 months and 5 months follow-up. To date, there have been two local recurrences in the complete responders. Both patients had nasopharyngeal primary; one was retreated with radioactive Cesium-137 implant and the other died from the disease. CLINICAL FEASIBILITY: The average treatment time for a three-arc treatment was 17.5 minutes and 2.5 minutes for each additional arc. Eleven patients (55%) had four-arc treatment while six patients (30%) had five-arc treatment and three patients (15%) had three-arc treatment. Immobilization was reproducible within less than 2 mm. The treatment planning, QA and documentation prior to treatment averaged 2 days. DOSIMETRY: The mean doses to the primary and secondary targets were 64.4 Gy and 54.4 Gy, respectively; 8.9% of the primary target volume and 11.6% of the secondary target volume were below prescribed dose goal. The mean dose delivered to the mandible was 30 Gy, spinal cord 17 Gy, ipsilateral parotid 23 Gy, and contralateral parotid 21 Gy. COST: Total Medicare allowable charge for SMART boost was $7000 compared to $8600 (conventional) and $9400 (accelerated fractionation). CONCLUSIONS: SMART boost technique is an accelerated radiotherapy scheme that can be delivered with acceptable toxicity. It allows parotid sparing as evidenced both clinically and by dosimetry. Initial tumor response has been encouraging. It is clinically feasible and cost saving. A larger population of patients and a long-term fol


Asunto(s)
Carcinoma Adenoide Quístico/radioterapia , Carcinoma de Células Escamosas/radioterapia , Fraccionamiento de la Dosis de Radiación , Neoplasias de Cabeza y Cuello/radioterapia , Radioterapia Conformacional/métodos , Anciano , Estudios de Factibilidad , Femenino , Humanos , Inmovilización , Masculino , Persona de Mediana Edad , Traumatismos por Radiación/etiología , Radioterapia Conformacional/efectos adversos , Factores de Tiempo
20.
Cornea ; 23(7): 740-3, 2004 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-15448507

RESUMEN

PURPOSE: To describe a case of mucous membrane pemphigoid (MMP) with ocular manifestations in a patient subsequently diagnosed with B-cell chronic lymphocytic leukemia (CLL). METHODS: Case report and literature review. RESULTS: A 64-year-old man presented with redness and irritation of both eyes. The patient also had blistering lesions on the roof of his mouth, trunk, and buttocks as well as bilateral conjunctival ulceration and symblepharon formation. A complete blood count performed before initiating treatment of presumed mucous membrane pemphigoid revealed a markedly increased white blood cell count (83,920) with a predominance of lymphocytes. Hematologic evaluation including immunophenotyping flow cytometry resulted in the diagnosis of B-cell chronic lymphocytic leukemia. Cyclophosphamide treatment improved his MMP and decreased the white blood cell count. CONCLUSIONS: Mucous membrane pemphigoid has been reported in association with a variety of nonhematologic malignancies. This case suggests that mucous membrane pemphigoid may also occur in B-cell CLL and supports the concept that autoantibodies play a role in the pathogenesis of this cicatricial conjunctival disease.


Asunto(s)
Enfermedades de la Conjuntiva/etiología , Leucemia Linfocítica Crónica de Células B/complicaciones , Penfigoide Benigno de la Membrana Mucosa/complicaciones , Úlcera/etiología , Enfermedades de la Conjuntiva/patología , Ciclofosfamida/uso terapéutico , Humanos , Inmunosupresores/uso terapéutico , Masculino , Persona de Mediana Edad , Penfigoide Benigno de la Membrana Mucosa/tratamiento farmacológico , Úlcera/patología
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