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1.
Cureus ; 16(6): e62785, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-39036150

RESUMEN

Erythema multiforme (EM) is a delayed, cell-mediated cutaneous disease with varying clinical manifestations. It is most commonly associated with infections but can also be associated with medications, vaccines, and autoimmune diseases. Non-steroidal anti-inflammatory Drugs (NSAIDs) are commonly used analgesics that have rare associations with EM and pancytopenia. These adverse reactions to NSAIDs can obscure definitive diagnosis due to their rarity. We present a case where an elderly female patient taking 600mg of ibuprofen up to four times a day for shoulder bursitis developed EM and pancytopenia. In this case, a 75-year-old female with a medical history of atrial fibrillation, essential hypertension, non-insulin-dependent type 2 diabetes mellitus, and ischemic stroke with residual right-sided visual impairment presented to our Emergency Department in 2023 with neck swelling, skin rash, and ulceration of the oral cavity. She reported a generalized, targetoid body rash that occurred 15 days after she started taking ibuprofen regularly for left shoulder bursitis. No other medications were started before, after, or during this time period. CBC on admission was remarkable for a white blood cell count of 1.5x109/L, hemoglobin of 6.5 g/dL, and platelet count <10x109/L, consistent with pancytopenia. Ibuprofen was discontinued, and the patient was treated supportively with analgesia and packed red blood cell transfusions. Testing for HIV, antinuclear antibodies (ANA) panel, Hepatitis panel, and copper and zinc levels were negative. A biopsy of a targetoid lesion on the skin showed changes consistent with EM. Esophagogastroduodenoscopy revealed no actively bleeding lesions or ulcers in the stomach mucosa. The patient's blood counts eventually recovered with supportive treatment, and symptomatology improved. The patient was discharged six days after admission. Healthcare professionals should be aware of rare hematologic and immunologic side effects of NSAIDs, which may often be overlooked and misdiagnosed. More studies are needed to build on our wealth of knowledge regarding the etiology and management of EM, Steven Johnson syndrome (SJS), and toxic epidermal necrolysis (TEN).

2.
J Am Chem Soc ; 143(29): 10910-10919, 2021 07 28.
Artículo en Inglés | MEDLINE | ID: mdl-34255504

RESUMEN

As the only ribosomally encoded N-substituted amino acid, proline promotes distinct secondary protein structures. The high proline content in collagen, the most abundant protein in the human body, is crucial to forming its hallmark structure: the triple-helix. For over five decades, proline has been considered compulsory for synthetic designs aimed at recapitulating collagen's structure and properties. Here we describe that N-substituted glycines (N-glys), also known as peptoid residues, exhibit a general triple-helical propensity similar to or greater than proline, enabling synthesis of stable triple-helical collagen mimetic peptides (CMPs) with unprecedented side chain diversity. Supported by atomic-resolution crystal structures as well as circular dichroism and computational characterizations spanning over 30 N-gly-containing CMPs, we discovered that N-glys stabilize the triple-helix primarily by sterically preorganizing individual chains into the polyproline-II helix. We demonstrated that N-glys with exotic side chains including a "click"-able alkyne and a photosensitive side chain enable CMPs for functional applications including the spatiotemporal control of cell adhesion and migration. The structural principles uncovered in this study open up opportunities for a new generation of collagen-mimetic therapeutics and materials.


Asunto(s)
Colágeno/síntesis química , Glicina/química , Péptidos/síntesis química , Colágeno/química , Estructura Molecular , Péptidos/química
3.
Mol Cancer Ther ; 17(11): 2297-2308, 2018 11.
Artículo en Inglés | MEDLINE | ID: mdl-30093568

RESUMEN

The TAM (TYRO3, AXL, MERTK) family receptor tyrosine kinases (RTK) play an important role in promoting growth, survival, and metastatic spread of several tumor types. AXL and MERTK are overexpressed in head and neck squamous cell carcinoma (HNSCC), triple-negative breast cancer (TNBC), and non-small cell lung cancer (NSCLC), malignancies that are highly metastatic and lethal. AXL is the most well-characterized TAM receptor and mediates resistance to both conventional and targeted cancer therapies. AXL is highly expressed in aggressive tumor types, and patients with cancer are currently being enrolled in clinical trials testing AXL inhibitors. In this study, we analyzed the effects of AXL inhibition using a small-molecule AXL inhibitor, a monoclonal antibody (mAb), and siRNA in HNSCC, TNBC, and NSCLC preclinical models. Anti-AXL-targeting strategies had limited efficacy across these different models that, our data suggest, could be attributed to upregulation of MERTK. MERTK expression was increased in cell lines and patient-derived xenografts treated with AXL inhibitors and inhibition of MERTK sensitized HNSCC, TNBC, and NSCLC preclinical models to AXL inhibition. Dual targeting of AXL and MERTK led to a more potent blockade of downstream signaling, synergistic inhibition of tumor cell expansion in culture, and reduced tumor growth in vivo Furthermore, ectopic overexpression of MERTK in AXL inhibitor-sensitive models resulted in resistance to AXL-targeting strategies. These observations suggest that therapeutic strategies cotargeting both AXL and MERTK could be highly beneficial in a variety of tumor types where both receptors are expressed, leading to improved survival for patients with lethal malignancies. Mol Cancer Ther; 17(11); 2297-308. ©2018 AACR.


Asunto(s)
Resistencia a Antineoplásicos , Terapia Molecular Dirigida , Proteínas Proto-Oncogénicas/antagonistas & inhibidores , Proteínas Tirosina Quinasas Receptoras/antagonistas & inhibidores , Tirosina Quinasa c-Mer/metabolismo , Animales , Línea Celular Tumoral , Proliferación Celular , Sinergismo Farmacológico , Femenino , Humanos , Ratones Desnudos , Proteínas Proto-Oncogénicas/metabolismo , Proteínas Tirosina Quinasas Receptoras/metabolismo , Transducción de Señal , Tirosina Quinasa c-Mer/antagonistas & inhibidores , Tirosina Quinasa del Receptor Axl
4.
Allergy Asthma Proc ; 39(5): 377-383, 2018 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-30153888

RESUMEN

BACKGROUND: Allergen specific immunoglobulin E (sIgE) levels predictive of shrimp allergy have not been identified, but these may be helpful in identifying patients at risk for shrimp-induced allergic reactions. OBJECTIVE: This study sought to identify component resolved diagnostic tests useful for diagnosis of shrimp allergy in patients with or without house-dust mite (HDM) sensitization to the major allergen cysteine protease (Der p 1). METHODS: Patients with positive skin-prick test (SPT) results and/or sIgE values were recruited. Shrimp allergy was classified by oral food challenge (OFC) or by a clear history of anaphylaxis after shrimp ingestion. Patients with shrimp allergy and patients who were tolerant were further classified based on HDM sensitivity (Der p 1 > 0.35 kUA/L). Testing for sIgE to total shrimp, and shrimp and HDM components was performed. The Fisher exact test, Wilcoxon sum rank test, and receiver operating characteristics analyses were used to compare sIgE levels in patients with allergy and patients who were tolerant. RESULTS: Of 79 patients recruited, 12 patients with shrimp allergy (7 with positive OFC results and 5 with a history of anaphylaxis) and 18 patients who were shrimp tolerant were enrolled. Of the patients not HDM sensitized, sIgE levels to shrimp (10.5 kUA/L, p = 0.012) and Der p 10 (4.09 kUA/L, p = 0.035) were higher in patients with shrimp allergy. Shrimp sIgE of ≥3.55 kUA/L had 100% diagnostic sensitivity and 85.7% specificity (receiver operating characteristic 0.94 [0.81, 1.0] 95% CI) and Der p 10 sIgE levels of ≥3.98 kUA/L had a diagnostic sensitivity of 80% and specificity of 100% (receiver operating characteristic 0.86 [0.57, 1.0] 95% CI) for prediction of clinical reactivity. CONCLUSION: HDM sensitization influences shrimp and HDM component sIgE levels and, consequently, their diagnostic accuracy in shrimp allergy. In our series, in the patients who were non-HDM sensitized, a shrimp sIgE level of >3.55 kUA/L showed 100% sensitivity and, Der p 10 sIgE of >3.98 kUA/L showed 100% specificity for the diagnosis of shrimp allergy. These levels may not be applicable to every patient and, therefore, may not obviate the need for OFC.


Asunto(s)
Alérgenos/inmunología , Decápodos/inmunología , Hipersensibilidad a los Alimentos/diagnóstico , Adolescente , Adulto , Anciano , Animales , Niño , Preescolar , Reacciones Cruzadas/inmunología , Femenino , Humanos , Inmunoglobulina E/sangre , Inmunoglobulina E/inmunología , Masculino , Persona de Mediana Edad , Curva ROC , Sensibilidad y Especificidad , Pruebas Cutáneas , Adulto Joven
5.
Thyroid ; 23(10): 1233-7, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23758055

RESUMEN

BACKGROUND: As defined by the Dietary Supplement Health and Education Act 1997, such substances as herbs and dietary supplements fall under general Food and Drug Administration supervision but have not been closely regulated to date. We examined the thyroid hormone content in readily available dietary health supplements marketed for "thyroid support." METHODS: Ten commercially available thyroid dietary supplements were purchased. Thyroid supplements were dissolved in 10 mL of acetonitrile and water with 0.1% trifloroacetic acid and analyzed using high-performance liquid chromatography for the presence of both thyroxine (T4) and triiodothyronine (T3) using levothyroxine and liothyronine as a positive controls and standards. RESULTS: The amount of T4 and T3 was measured separately for each supplement sample. Nine out of 10 supplements revealed a detectable amount of T3 (1.3-25.4 µg/tablet) and 5 of 10 contained T4 (5.77-22.9 µg/tablet). Taken at the recommended dose, 5 supplements delivered T3 quantities of greater than 10 µg/day, and 4 delivered T4 quantities ranging from 8.57 to 91.6 µg/day. CONCLUSIONS: The majority of dietary thyroid supplements studied contained clinically relevant amounts of T4 and T3, some of which exceeded common treatment doses for hypothyroidism. These amounts of thyroid hormone, found in easily accessible dietary supplements, potentially expose patients to the risk of alterations in thyroid levels even to the point of developing iatrogenic thyrotoxicosis. The current study results emphasize the importance of patient and provider education regarding the use of dietary supplements and highlight the need for greater regulation of these products, which hold potential danger to public health.


Asunto(s)
Seguridad de Productos para el Consumidor , Suplementos Dietéticos/análisis , Contaminación de Alimentos , Enfermedades de la Tiroides/prevención & control , Tiroxina/análisis , Triyodotironina/análisis , Animales , Cromatografía Líquida de Alta Presión , Suplementos Dietéticos/efectos adversos , Suplementos Dietéticos/economía , Suplementos Dietéticos/normas , Técnicas Electroquímicas , Etiquetado de Alimentos , Humanos , Internet/economía , Maryland/epidemiología , Educación del Paciente como Asunto , Riesgo , Tiroides (USP)/química , Enfermedades de la Tiroides/dietoterapia , Glándula Tiroides/química , Tirotoxicosis/inducido químicamente , Tirotoxicosis/epidemiología , Tirotoxicosis/etiología , Tiroxina/efectos adversos , Tiroxina/envenenamiento , Triyodotironina/efectos adversos , Triyodotironina/envenenamiento , Estados Unidos/epidemiología
6.
Langmuir ; 27(10): 6179-84, 2011 May 17.
Artículo en Inglés | MEDLINE | ID: mdl-21500821

RESUMEN

We present the preparation of electrically conductive, porous polypyrrole surfaces and demonstrate their use as an interactive substrate for neuronal growth. Nerve growth factor (NGF)-loaded porous conducting polymers were initially prepared by electrochemical deposition of a mixture of pyrrole monomers and NGF into two- or three-dimensional particle arrays followed by subsequent removal of a sacrificial template. Morphological observation by scanning electron microscopy (SEM) revealed these to possess high regularity and porosity with well-defined topographical features. A four-point probe study demonstrated remarkable electrical activities despite the presence of voids. In addition, we investigated the effects of these surfaces on cellular behaviors using PC 12 cells in the presence and absence of electrical stimulation. Our results suggest that the surface topography as well as an applied electrical field can play a crucial role in determining further cell responses. Indeed, surface-induced preferential regulation leads to enhanced cellular viability and neurite extension. Establishing the underlying cellular mechanisms in response to various external stimuli is essential in that one can elicit positive neuronal guidance and modulate their activities by engineering a series of electrical, chemical, and topographical cues.


Asunto(s)
Conductividad Eléctrica , Neuronas/citología , Neuronas/efectos de los fármacos , Polímeros/química , Polímeros/farmacología , Pirroles/química , Pirroles/farmacología , Animales , Supervivencia Celular/efectos de los fármacos , Estimulación Eléctrica , Factor de Crecimiento Nervioso/metabolismo , Neuronas/metabolismo , Células PC12 , Porosidad , Ratas , Propiedades de Superficie
7.
Br J Haematol ; 150(5): 592-600, 2010 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-20553270

RESUMEN

During definitive erythropoiesis, erythroid precursors undergo differentiation through multiple nucleated states to an enucleated reticulocyte, which loses its residual RNA/organelles to become a mature erythrocyte. Over the course of these transformations, continuous changes in membrane proteins occur, including shifts in protein abundance, rates of expression, isoform prominence, states of phosphorylation, and stability. In an effort to understand when assembly of membrane proteins into an architecture characteristic of the mature erythrocyte occurs, we quantitated the lateral diffusion of the most abundant membrane protein, band 3 (AE1), during each stage of erythropoiesis using single particle tracking. Analysis of the lateral trajectories of individual band 3 molecules revealed a gradual reduction in mobility of the anion transporter as erythroblasts differentiated. Evidence for this progressive immobilization included a gradual decline in diffusion coefficients as determined at a video acquisition rate of 120 frames/s and a decrease in the percentage of compartment sizes >100 nm. Because complete acquisition of the properties of band 3 seen in mature erythrocytes is not observed until circulating erythrocytes are formed, we suggest that membrane maturation involves a gradual and cooperative assembly process that is not triggered by the synthesis of any single protein.


Asunto(s)
Proteína 1 de Intercambio de Anión de Eritrocito/metabolismo , Eritroblastos/metabolismo , Membrana Eritrocítica/metabolismo , Diferenciación Celular , Núcleo Celular/metabolismo , Células Cultivadas , Difusión , Eritroblastos/citología , Eritropoyesis/fisiología , Humanos , Reticulocitos/citología , Reticulocitos/metabolismo
8.
Infect Control Hosp Epidemiol ; 31(1): 92-4, 2010 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-19929690

RESUMEN

We investigated the mortality associated with Acinetobacter baumannii complex bacteremia among a cohort of patients hospitalized for war-related trauma. Despite a high prevalence of multidrug-resistant strains, the 30-day mortality rate was 2%. For relatively young patients with war-related trauma, A. baumannii complex bacteremia appears to be associated with a low risk of death.


Asunto(s)
Acinetobacter baumannii/aislamiento & purificación , Bacteriemia/mortalidad , Personal Militar , Guerra , Heridas y Lesiones/etiología , Infecciones por Acinetobacter/microbiología , Infecciones por Acinetobacter/mortalidad , Acinetobacter baumannii/clasificación , Adolescente , Adulto , Bacteriemia/microbiología , District of Columbia , Femenino , Hospitales Militares/estadística & datos numéricos , Humanos , Masculino , Adulto Joven
9.
Proc Natl Acad Sci U S A ; 102(6): 1933-8, 2005 Feb 08.
Artículo en Inglés | MEDLINE | ID: mdl-15671173

RESUMEN

The overexpression of P-glycoprotein (P-gp) causes resistance to chemotherapy in many tumor types. Here, we report intercellular transfer of functional P-gp from P-gp-positive to P-gp-negative cells in vitro and in vivo. The expression of acquired P-gp is transient in isolated cells but persists in the presence of P-gp-positive cells or under the selective pressure of colchicine. The intercellular transfer of functional P-gp occurs between different tumor cell types and results in increased drug resistance both in vitro and in vivo. Most importantly, the acquired resistance permits tumor cells to survive potentially toxic drug concentrations long enough to develop intrinsic P-gp-mediated resistance. P-gp transfer also occurs to putative components of tumor stroma, such as fibroblasts, raising the possibility that multidrug resistance could be conferred by resistant tumor cells to critical stromal elements within the tumor mass. This is the first report, to our knowledge, that a protein transferred between cells retains its function and confers a complex biologic property upon the recipient cell. These findings have important implications for proteomic analyses in tumor samples and resistance to cancer therapy.


Asunto(s)
Miembro 1 de la Subfamilia B de Casetes de Unión a ATP/metabolismo , Resistencia a Múltiples Medicamentos , Resistencia a Antineoplásicos , Neuroblastoma/metabolismo , Miembro 1 de la Subfamilia B de Casetes de Unión a ATP/genética , Animales , Línea Celular Tumoral , Colchicina/metabolismo , Ensayos de Selección de Medicamentos Antitumorales , Humanos , Ratones , Ratones Endogámicos BALB C , Transporte de Proteínas , Proteínas Recombinantes de Fusión/genética , Proteínas Recombinantes de Fusión/metabolismo
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