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1.
PLoS Negl Trop Dis ; 18(4): e0012090, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38598562

RESUMEN

BACKGROUND: The Alliance for the Global Elimination of Trachoma (GET) endorses the full SAFE strategy to eliminate trachoma; Surgery (for trichiasis), Antibiotics (to reduce the community pool of infection, Facial cleanliness, and Environmental improvement (to decrease transmission). There is no accepted measure of facial cleanliness. This study compared two possible metrics for facial cleanliness. METHOD/FINDINGS: Metric one: Clean face was defined as observed absence of ocular and nasal discharge on the face. Metric two: observing a grade of dirtiness (scale 10 = lightest to 0 = darkest) on a standard facial wipe. The reliability of grading a child's face or grading a facial wipe was determined in children in Kongwa Tanzania. We also observed both measurements in a cohort of 202 children ages 1 to <7years prior to face cleaning, immediately afterwards, and 4 hours afterwards. Fifty of the children did not have face cleaning and were controls. Intra-and interobserver reliability was similar for both measures, the latter = 0.53 for observing a clean face and 0.52 for grading a facial wipe. There was no correlation between the two. Both measures detected facial cleaning, compared to control children who were not cleaned, immediately after cleaning; control children with 53% clean faces and wipe score of 6.7 compared to cleaned children with 88% clean faces and wipe score of 8 (p = .0001, p = < .0001, respectively). Both measures also detected face washing 4 hours previously compared to controls. CONCLUSIONS: The two metrics were equally reliable, and both measured the behavior of face washing. They measure different aspects of a clean face; one measures the amount of dirt on wiped area and the other measures ocular and nasal discharge. Both measurements appear to capture the behavior of facial cleaning, and the choice of metric would appear to rest on the measurement that captures the stated objective of the behavior, consideration of costs, training, logistics, and implementation.


Asunto(s)
Cara , Higiene , Tracoma , Humanos , Tracoma/prevención & control , Preescolar , Tanzanía/epidemiología , Lactante , Femenino , Masculino , Niño , Higiene/normas , Reproducibilidad de los Resultados
2.
Epilepsia ; 64(2): 386-395, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36318046

RESUMEN

OBJECTIVE: The objectives of this study were to assess the accuracy of parental seizure detection in infants with antenatally diagnosed tuberous sclerosis complex (TSC), and to document the total seizure burden (clinical and subclinical) in those patients who met criteria for prolonged electroencephalography (EEG) recording. METHODS: Consecutive infants at a single institution with antenatally diagnosed TSC who met criteria for prolonged video-EEG (vEEG) were recruited to this study. The vEEG data were reviewed and when a seizure was identified on EEG, the video and audio recording was assessed for evidence of clinical seizure and, if present, whether there was evidence of parent seizure identification. RESULTS: Nine infants were enrolled, for whom 674 focal seizures were identified in eight of nine patients across 24 prolonged vEEG recordings, with vEEG total duration of 634 h 49 min (average seizure frequency of 1 focal seizure/h). Only 220 of 674 (32.6%) were clinical seizures, 395 of 674 (58.6%) were subclinical seizures, and 59 of 674 seizures could not be classified. Only 63 of 220 clinical seizures (28.6%) were identified by parents, with 157 of 220 (71.4%) not identified. Thirty clusters of epileptic spasms were detected in one patient. At least one clinical epileptic spasm occurred in 2 of 30 clusters (6.7%), 24 of 30 clusters of epileptic spasms (80%) were electrographic only, and classification was uncertain for 4 of 30 clusters (13.3%). No clinical epileptic spasms were detected by parents. Clinical seizure frequency was significantly underestimated by parents for all patients. SIGNIFICANCE: This study demonstrates that in infants with TSC who met criteria for prolonged vEEG, (1) parents significantly under recognize total clinical seizure count, (2) parents fail to identify epileptic spasms, and (3) seizure frequency is high. This highlights that epilepsy treatment decisions should not be based solely on parental clinical seizure identification. Prolonged vEEG monitoring may have an important role in the routine epilepsy care of infants with TSC, as demonstrating undetected high clinical seizure frequency may allow improved epilepsy management decisions.


Asunto(s)
Epilepsia , Espasmos Infantiles , Esclerosis Tuberosa , Humanos , Lactante , Esclerosis Tuberosa/complicaciones , Esclerosis Tuberosa/diagnóstico , Epilepsia/diagnóstico , Electroencefalografía , Espasmos Infantiles/diagnóstico , Espasmos Infantiles/etiología , Convulsiones/diagnóstico , Convulsiones/etiología , Espasmo
3.
Ann Neurol ; 92(5): 895-901, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-35947102

RESUMEN

NOTCH1 belongs to the NOTCH family of proteins that regulate cell fate and inflammatory responses. Somatic and germline NOTCH1 variants have been implicated in cancer, Adams-Oliver syndrome, and cardiovascular defects. We describe 7 unrelated patients grouped by the presence of leukoencephalopathy with calcifications and heterozygous de novo gain-of-function variants in NOTCH1. Immunologic profiling showed upregulated CSF IP-10, a cytokine secreted downstream of NOTCH1 signaling. Autopsy revealed extensive leukoencephalopathy and microangiopathy with vascular calcifications. This evidence implicates that heterozygous gain-of-function variants in NOTCH1 lead to a chronic central nervous system (CNS) inflammatory response resulting in a calcifying microangiopathy with leukoencephalopathy. ANN NEUROL 2022;92:895-901.


Asunto(s)
Displasia Ectodérmica , Leucoencefalopatías , Humanos , Receptor Notch1/genética , Receptor Notch1/metabolismo , Quimiocina CXCL10 , Sistema Nervioso Central/metabolismo
4.
Eur Heart J Case Rep ; 6(2): ytac050, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-35187393

RESUMEN

BACKGROUND: IgG4-related disease (IgG4-RD) is a fibro-inflammatory condition classically causing retroperitoneal fibrosis, aortitis, thyroiditis, or pancreatitis. Diagnosis includes the presence of lymphoplasmacytic infiltrate (with >40% ratio IgG4+:IgG plasma cells) and fibrosis. Cardiac involvement may include aortic, pericardial, or coronary disease. Coronary manifestations encompass obstructive intra-luminal lesions, external encasing pseudo-tumour on imaging, or lymphoplasmacytic arteritis. CASE SUMMARY: Case 1: A fit and healthy 50-year-old man was found deceased. His only known medical condition was treated Hashimoto's thyroiditis. Post-mortem examination demonstrated an isolated severe stenosis of the left anterior descending (LAD) coronary artery without histopathological evidence of acute myocardial infarction. Coronary plaque histopathology showed florid IgG4-positive plasma cell infiltrate throughout all layers of the artery with dense fibrous tissue connective tissue stroma, all features consistent with coronary artery IgG4-RD. Case 2: A 48-year-old man collapsed at work. Computed tomography scan 1 week prior reported an ill-defined para-aortic retroperitoneal soft tissue density. No cardiac symptoms were reported in life. Post-mortem examination showed coronary arteritis and peri-arteritis with sclerosing peri-aortitis in the LAD. There was myocardial fibrosis of the anterior left ventricle and focal myocarditis of the right ventricle. DISCUSSION: IgG4-related disease presenting as sudden cardiac death without any preceding symptoms is very rare (six prior cases identified on literature review). Reported targeted successful interventions for intracoronary IgG4-RD diagnosed in life have included steroid therapy and B cell depleting therapy (i.e. rituximab). If cardiac symptoms are present in a patient with known IgG4-RD, cardiac investigations should be promptly arranged.

6.
Am J Kidney Dis ; 78(4): 611-613, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34280507

RESUMEN

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) continues to spread around the world. As of the end of June 2021, there were approximately 181 million confirmed cases and more than 3.9 million deaths across the globe. The colossal impact of coronavirus disease 2019 (COVID-19) is driving the biggest vaccination campaign in human history. All 3 vaccines authorized for emergency use by the US Food and Drug Administration (Pfizer-BioNTech, Moderna, and Janssen/Johnson & Johnson) have been thoroughly studied and found to be safe and effective in preventing severe COVID-19 cases. While short-term side effects of COVID-19 vaccine resemble those of other vaccines, long-term side effects remain unknown. Rare side effects continue to surface as millions of people receive COVID-19 vaccines around the world, as compared with the thousands enrolled in the clinical trials. We report a case of new-onset renal-limited ANCA-associated vasculitis (AAV) in a 78-year-old woman with previously normal kidney function after receiving the Pfizer-BioNTech COVID-19 vaccine. The patient developed acute kidney injury with proteinuria and microscopic hematuria with many dysmorphic red blood cells in the urine. Anti-myeloperoxidase antibody titer was elevated. Kidney biopsy showed pauci-immune crescentic necrotizing glomerulonephritis. Kidney function improved after treatment with steroids and rituximab. Our patient had normal routine laboratory testing before the vaccination. Although this case cannot demonstrate a causal relationship between COVID-19 vaccination and AAV, ongoing surveillance for similar complications would be prudent as worldwide vaccination efforts continue.


Asunto(s)
Vasculitis Asociada a Anticuerpos Citoplasmáticos Antineutrófilos/inducido químicamente , Vasculitis Asociada a Anticuerpos Citoplasmáticos Antineutrófilos/diagnóstico , Vacunas contra la COVID-19/efectos adversos , Anciano , Vasculitis Asociada a Anticuerpos Citoplasmáticos Antineutrófilos/sangre , Vacuna BNT162 , Femenino , Humanos
8.
Forensic Sci Med Pathol ; 13(3): 317-327, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-28526950

RESUMEN

The purpose of this study was to investigate the impact of post-mortem computed-tomography angiography (PMCTA) on the histology of the liver, kidneys and heart. Multiple tissue cores were collected from the liver, left and right kidneys and left ventricle utilizing CT-guided biopsy. Subsequent whole body PMCTA was performed using a solution of polyethylene glycol and iodinated radiographic contrast, and an embalming pump. Corresponding biopsy cores were collected at autopsy, and blinded histology analysis assessing for PMCTA-induced histology artefact was performed. The blinded analysis of pre-PMCTA and post-PMCTA biopsy samples demonstrated that whole body PMCTA had no effect on the histological analyses of the liver (0%, CI = 0-13.7%), left ventricle of the heart (0%, CI = 0-36.9%) and right kidney (0%, CI = 13.2%), however likely caused increased Bowman's capsule spaces in the left kidney of one case (4%, CI = 0.01-20.4%). Other artefactual histological changes identified included eosinophilic material in the liver, whiter interstitium and dilated tubules in kidney samples, and autolysis-related changes, however these could not be categorically attributed to the PMCTA procedure. PMCTA causes zero or minimal effect to the histological examination of the liver, left kidney, right kidney and left ventricle, and as such performing PMCTA prior to autopsy is unlikely to impact autopsy histological results in these organs.


Asunto(s)
Angiografía por Tomografía Computarizada , Medios de Contraste , Ventrículos Cardíacos/patología , Biopsia Guiada por Imagen , Riñón/patología , Hígado/patología , Adulto , Anciano , Anciano de 80 o más Años , Autopsia/métodos , Biopsia con Aguja Gruesa , Femenino , Patologia Forense , Humanos , Yopamidol , Masculino , Persona de Mediana Edad , Imagen de Cuerpo Entero , Adulto Joven
9.
J Forensic Leg Med ; 42: 8-10, 2016 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-27213840

RESUMEN

We present a case of Fabry disease with an uncommon pattern of asymmetrical hypertrophy with septal prominence resulting in an erroneous diagnosis of hypertrophic cardilmyopathy clinically. The deceased presented for a medicolegal autopsy following his sudden death after an AV node ablation. Fabry disease continues to be an important misdiagnosis of hypertrophic cardiomyopathy in a clinical setting. Early diagnosis of Fabry disease is essential so that early treatment can be instituted.


Asunto(s)
Nodo Atrioventricular/cirugía , Cardiomiopatía Hipertrófica/etiología , Ablación por Catéter/efectos adversos , Muerte Súbita/etiología , Enfermedad de Fabry/diagnóstico , Anciano , Errores Diagnósticos , Humanos , Masculino , Marcapaso Artificial
12.
Echocardiography ; 30(8): E227-30, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23808893

RESUMEN

A 25-year-old student presenting with pleuritic chest pain, elevated troponin levels and subtle electrocardiogram abnormalities was treated for presumptive myopericarditis. On echocardiography, a lower than expected mitral annular displacement and systolic velocity were identified along with abnormalities in left ventricular strain generation that matched areas of edema and necrosis by cardiac magnetic resonance imaging. The patient was treated with nonsteroidal antiinflammatory drugs and colchicine, and both the symptoms and echocardiographic abnormalities rapidly resolved. These novel findings suggest that changes in mitral annular displacement and systolic velocity occur in acute myopericarditis and may be useful in following the course of the disease.


Asunto(s)
Ecocardiografía/métodos , Diagnóstico por Imagen de Elasticidad/métodos , Válvula Mitral/diagnóstico por imagen , Miocarditis/diagnóstico por imagen , Pericarditis/diagnóstico por imagen , Enfermedad Aguda , Adulto , Antiinflamatorios no Esteroideos/uso terapéutico , Colchicina/uso terapéutico , Diagnóstico Diferencial , Humanos , Masculino , Miocarditis/tratamiento farmacológico , Pericarditis/tratamiento farmacológico , Resultado del Tratamiento , Moduladores de Tubulina/uso terapéutico
13.
Langmuir ; 26(17): 13823-30, 2010 Sep 07.
Artículo en Inglés | MEDLINE | ID: mdl-20684552

RESUMEN

The phase behavior of model polymer-colloid mixtures is measured for solutions approaching the "protein limit", that is, when the radius of gyration of the polymer (R(g)) is greater than or approximately equal to the radius of the colloid (R). Cationic nanoparticles are mixed with poly(ethylene oxide) (PEO) or poly(vinyl pyrolidone) (PVP) at size ratios of R(g)/R = 0.7 and 1.8. The addition of PEO to stable nanoparticle dispersions leads to depletion flocculation in both deionized water and buffer solutions. The instability mechanism for the PVP-nanoparticle system depends on the suspension medium. In water, bridging occurs below the saturation adsorption of PVP, whereas depletion phase separation is evident at concentrations exceeding those necessary to saturate the particle surface. In acidic buffer, PVP addition results in depletion phase separation. The difference between bridging and depletion is distinguished by both visual appearances and rheological measurements. There is no trend (within error bars) in the polymer concentration required to induce instability with increasing R(g)/R in contrast with theoretical predictions. This is most likely due to adsorption of polymer onto the particle surface.


Asunto(s)
Nanopartículas/química , Polietilenglicoles/química , Povidona/química , Coloides/química , Tamaño de la Partícula , Propiedades de Superficie
14.
Langmuir ; 26(9): 6262-7, 2010 May 04.
Artículo en Inglés | MEDLINE | ID: mdl-20095547

RESUMEN

The adsorption of two polymers, poly(ethylene oxide) (PEO) and poly(vinyl pyrrolidone) PVP, onto cationic nanoparticles suspended in both water and a buffer solution is studied via isothermal titration calorimetry (ITC). These are model systems studied previously to understand polymer-induced phase separation and bridging flocculation in the protein limit. ITC measurements provide critical information for rationalizing the effects of polymer type and added buffer solution on the loss of stability of nanoparticle-polymer solutions. For PEO, weak segmental adsorption energies of approximately 0.2k(B)T for PEO in water and buffer are consistent with depletion phase separation. For PVP in water, segmental adsorption energies on the order of approximately 1.6k(B)T support the observed bridging flocculation, whereas a weaker adsorption energy of approximately 0.7k(B)T for PVP in buffer is consistent with depletion phase separation. Multilayer adsorption is observed in buffer solutions, which corroborates a measured increase in the hydrodynamic size of the polymer-nanoparticle complexes with added buffer. The entropy of adsorption is calculated from equilibrium constants determined by combining ITC and adsorption isotherms.

15.
Hum Pathol ; 41(3): 392-400, 2010 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-20004937

RESUMEN

Dead in bed syndrome is a poorly understood cause of sudden death in young people with type 1 diabetes. The underlying cause remains unknown. One possible explanation may involve prolongation of the QT interval followed by a terminal malignant arrhythmia. Risk factors associated with QT interval prolongation include hypoglycemia and cardiac autonomic neuropathy. We sought to identify myocardial cellular changes and genetic influences that may contribute to the pathogenesis of dead in bed syndrome. Post-mortem reports between 1994 and 2006 from the 2 largest Departments of Forensic Medicine in Australia were reviewed for dead in bed syndrome cases. Post-mortem heart sections were immunohistochemically stained for collagen types I and III and connective tissue growth factor (CTGF). Genomic DNA was prepared from post-mortem samples, and genetic analysis was performed in the SCN5A, G6PC, PHOX2B, and CTGF genes. Twenty-two dead in bed syndrome cases were identified and staining of heart sections for collagen I and III, and CTGF showed no differences between dead in bed syndrome cases and controls. Genetic screening of SCN5A revealed 3 silent polymorphisms A29A, E1061E, and D1819D and 1 protein-changing variant H558R. No genetic variants were found in G6PC, PHOX2B, and CTGF, and dead in bed syndrome cases were not associated with the G-945C CTGF promoter polymorphism. In conclusion, this study is the first to investigate potential pathogenic mechanisms underlying the dead in bed syndrome in type 1 diabetes with the results substantially adding to knowledge of this condition. Understanding the causes and triggers of dead in bed syndrome will be critical in facilitating the identification of patients with type 1 diabetes at highest risk of developing sudden death.


Asunto(s)
Muerte Súbita/patología , Diabetes Mellitus Tipo 1/patología , Miocardio/patología , Adolescente , Adulto , Análisis de Varianza , Australia , Distribución de Chi-Cuadrado , Colágeno Tipo I/metabolismo , Colágeno Tipo III/metabolismo , Factor de Crecimiento del Tejido Conjuntivo/genética , Factor de Crecimiento del Tejido Conjuntivo/metabolismo , Muerte Súbita/etiología , Diabetes Mellitus Tipo 1/genética , Diabetes Mellitus Tipo 1/metabolismo , Predisposición Genética a la Enfermedad , Glucosa-6-Fosfatasa/genética , Proteínas de Homeodominio/genética , Humanos , Hipoglucemia/genética , Hipoglucemia/metabolismo , Hipoglucemia/patología , Inmunohistoquímica , Masculino , Miocardio/metabolismo , Canal de Sodio Activado por Voltaje NAV1.5 , Polimorfismo Genético/genética , Estudios Retrospectivos , Factores de Riesgo , Análisis de Secuencia de ADN , Canales de Sodio/genética , Factores de Transcripción/genética
16.
Langmuir ; 24(15): 8090-101, 2008 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-18605743

RESUMEN

Glycopolymers with repeat units comprised of the disaccharide trehalose and an oligoamine of increasing amine have been previously synthesized by our group and shown to efficiently deliver pDNA (plasmid DNA) to HeLa cells while remaining relatively nontoxic. Complexes formed between the most amine-dense of these polycations and pDNA were also found to be relatively stable in serum and have low aggregation, which is desirable for in vivo gene delivery. To lend insight into these interesting results, this study was aimed at investigating the binding strength and mechanism of interaction between these macromolecules, via isothermal titration calorimetry (ITC) and ethidium bromide exclusion assays. The size of these pDNA-polymer complexes, or polyplexes, at various states of formation was determined through light scattering and zeta-potential measurements. Varying degrees of pDNA secondary structure change occurred upon interaction with the polymers, as evidenced by circular dichroism spectra through increasing molar ratios of polymer amine to DNA phosphate, and Fourier transform infrared (FT-IR) results demonstrated stronger electrostatic binding with the phosphate backbone with the least amine-dense of the series. It was concluded that, depending on the number of secondary amines in the repeat unit, these polymers interact with pDNA via different mechanisms with varying extents of electrostatic interaction and hydrogen bonding. These differing mechanisms may affect the ability of trehalose to serve as a deterrent against aggregation in serum conditions and lend insight into the roles of polymer-pDNA binding during the complex transfection process.


Asunto(s)
Aminas/química , ADN/química , Plásmidos/química , Poliaminas/química , Trehalosa/química , Calorimetría , Dicroismo Circular , Estructura Molecular , Peso Molecular , Tamaño de la Partícula , Polielectrolitos , Potenciometría , Soluciones , Espectroscopía Infrarroja por Transformada de Fourier , Electricidad Estática , Termodinámica , Volumetría , Agua/química
17.
Langmuir ; 23(19): 9773-84, 2007 Sep 11.
Artículo en Inglés | MEDLINE | ID: mdl-17705512

RESUMEN

There is considerable interest in the binding and condensation of DNA with polycations to form polyplexes because of their possible application to cellular nucleic acid delivery. This work focuses on studying the binding of plasmid DNA (pDNA) with a series of poly(glycoamidoamine)s (PGAAs) that have previously been shown to deliver pDNA in vitro in an efficient and nontoxic manner. Herein, we examine the PGAA-pDNA binding energetics, binding-linked protonation, and electrostatic contribution to the free energy with isothermal titration calorimetry (ITC). The size and charge of the polyplexes at various ITC injection points were then investigated by light scattering and zeta-potential measurements to provide comprehensive insight into the formation of these polyplexes. An analysis of the calorimetric data revealed a three-step process consisting of two different endothermic contributions followed by the condensation/aggregation of polyplexes. The strength of binding and the point of charge neutralization were found to be dependent upon the hydroxyl stereochemistry of the carbohydrate moiety within each polymer repeat unit. Circular dichroism spectra reveal that the PGAAs induce pDNA secondary structure changes upon binding, which suggest a direct interaction between the polymers and the DNA base pairs. Infrared spectroscopy experiments confirmed both base pair and phosphate group interactions and, more specifically, showed that the stronger-binding PGAAs had more pronounced interactions at both sites. Thus, we conclude that the mechanism of poly(glycoamidoamine)-pDNA binding is most likely a combination of electrostatics and hydrogen bonding in which long-range Coulombic forces initiate the attraction and hydroxyl groups in the carbohydrate comonomer, depending on their stereochemistry, further enhance the association through hydrogen bonding to the DNA base pairs.


Asunto(s)
ADN/química , Plásmidos/química , Poliaminas/química , Amidas/química , Aminas/química , Sitios de Unión , Etidio/química , Glicosilación , Enlace de Hidrógeno , Conformación Molecular , Estructura Molecular , Tamaño de la Partícula , Polielectrolitos , Termodinámica
18.
Clin Colon Rectal Surg ; 18(3): 163-73, 2005 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-20011299

RESUMEN

Colorectal cancer is the third most common malignancy in men and women and accounts for 10% of all cancer deaths. The primary risk factor for colorectal cancer is advancing age, but other factors also play a role in its development, including genetic predisposition, smoking, alcohol consumption, obesity, and high-fat, low-fiber diet. Colon cancer survival is primarily related to the stage of disease at diagnosis. The main screening tests for colon cancer are fecal occult blood testing, flexible sigmoidoscopy, double-contrast barium enema, and colonoscopy. The pre-operative evaluation should include a complete blood count, carcinoembryonic antigen (CEA), colonoscopy, and chest radiograph. Other preoperative evaluations are patient specific or of unproven benefit. The operative procedure should include a bowel preparation, parenteral antibiotics, and deep venous thrombosis prophylaxis. The procedure performed must be tailored to the location of the colon cancer but should include complete, en bloc resection of the cancer and its lymphatic drainage, including locally invaded structures. The bowel margins of resection should be at least 5 cm from the tumor to minimize anastomotic recurrences. Laparoscopic colectomy has been shown to be as safe and effective as open colectomy for the treatment of colon cancer. The use of sentinel lymph node biopsy is feasible but has not yet been proved clinically useful. Surveillance after surgery for colon cancer is necessary to monitor for metastatic disease or local recurrence. Several groups have made surveillance recommendations including office visits, colonoscopy, and CEA monitoring.

19.
J Am Chem Soc ; 126(24): 7422-3, 2004 Jun 23.
Artículo en Inglés | MEDLINE | ID: mdl-15198572

RESUMEN

In this report, four new poly(d-glucaramidoamine)s (1-4) have been designed to lower the toxicity of conventional polymeric nucleic acid delivery vehicles by incorporating a carbohydrate comonomer within a polyethylenimine (PEI)-like backbone. Polymers 1-4 were synthesized via polycondensation of esterified d-glucaric acid and four different amine-containing comonomers [diethylenetriamine (1), triethylenetetramine (2), tetraethylenepentamine (3), and pentaethylenehexamine (4)] in methanol. Viscometry and NMR studies suggest that the polymers are mostly linear (for 1-4, the alpha value in the Mark-Houwink-Sakurada equation = 0.6-0.7), thus indicating that polymerization occurs predominantly through the primary amines with a low degree of branching off the secondary amines. Results of gel electrophoresis shift assays show that polymers 1-4 bind pDNA at N/P ratios of 5, 3, 2, and 2, respectively. Also, dynamic light scattering and TEM experiments indicate that 1-4 compact DNA into nanoparticles (polyplexes) between 140 and 440 nm at an N/P ratio of 30. Furthermore, polyplexes formed with 1-4 deliver pDNA (plasmid DNA) containing the firefly luciferase reporter gene to BHK-21 cells in a nontoxic and highly efficient manner (as determined by luciferase gene expression). In particular, polymer 4 reveals very high delivery efficiency (equivalent to linear PEI). This result may be due in part to the "proton sponge" hypothesis proposed by Behr et al. Polymers containing amines that are protonated in the endosomal pH range (between about 7.4-5.0) reveal enhanced gene delivery profiles.


Asunto(s)
ADN/química , ADN/genética , Expresión Génica , Técnicas de Transferencia de Gen , Vectores Genéticos/farmacología , Ácido Glucárico/farmacología , Nanotecnología , Nylons/farmacología , Animales , Supervivencia Celular/efectos de los fármacos , Supervivencia Celular/fisiología , Cricetinae , Vectores Genéticos/genética , Ácido Glucárico/análogos & derivados , Ácido Glucárico/síntesis química , Estructura Molecular , Nylons/síntesis química , Tamaño de la Partícula , Plásmidos/genética
20.
Ann Plast Surg ; 51(1): 17-22, 2003 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-12838120

RESUMEN

Upper thoracic wounds with exposed hardware from spinal instrumentation and previous radiation presents a subset of back wound coverage problems that lend themselves to a unique opportunity to use the distal trapezius musculocutaneous flap. The unradiated, healthy skin paddle can be transposed between the radiated skin edges to seal and cover the exposed hardware and achieve early primary healing of the back wound without the need for a skin graft. The authors review their series of the upper back radiated wounds reconstructed with the trapezius musculocutaneous flaps, immediately at the time of the spinal surgery and secondarily after the incisional wound breakdown, to cover the exposed hardware. Their contiguous skin flap design strategy, results, and complications are discussed.


Asunto(s)
Dorso/cirugía , Fijadores Internos , Traumatismos por Radiación/cirugía , Neoplasias de la Columna Vertebral/cirugía , Colgajos Quirúrgicos , Vértebras Torácicas/cirugía , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Procedimientos de Cirugía Plástica/métodos , Neoplasias de la Columna Vertebral/radioterapia , Neoplasias de la Columna Vertebral/secundario , Vértebras Torácicas/efectos de la radiación , Cicatrización de Heridas
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