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1.
J Cutan Pathol ; 50(4): 310-315, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36169222

RESUMEN

Endosalpingiosis is a pathologic phenomenon in which non-neoplastic fallopian tube epithelium implants in ectopic locations. It is an uncommon and poorly understood condition, with most cases occurring within the abdominopelvic cavity. Cutaneous presentations of endosalpingiosis are even more rare, with only six cases described in international literature to-date. This report describes an additional case of cutaneous endosalpingiosis. The lesion arose within the scar tissue of a Pfannenstiel incision from 4 years prior in a 24-year old, previously healthy African American female. Punch biopsy of the lesion revealed a cystic mass lined by PAX8+ ciliated columnar cells and a surrounding fibrotic stroma with focal CD10-positivity, consistent with a histopathologic diagnosis of endosalpingiosis. In addition, this report provides a comprehensive review of the other documented cases of cutaneous endosalpingiosis, as well as the proposed pathogenesis, histopathologic and clinical features, and potential treatment avenues for this unique clinical entity.


Asunto(s)
Cicatriz , Células Epiteliales , Femenino , Humanos , Adulto Joven , Adulto
2.
J Pept Sci ; 25(8): e3199, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31231935

RESUMEN

The aggregation of the 37-amino acid polypeptide human islet amyloid polypeptide (hIAPP), as either insoluble amyloid or as small oligomers, appears to play a direct role in the death of human pancreatic ß-islet cells in type 2 diabetes. hIAPP is considered to be one of the most amyloidogenic proteins known. The quick aggregation of hIAPP leads to the formation of toxic species, such as oligomers and fibers, that damage mammalian cells (both human and rat pancreatic cells). Whether this toxicity is necessary for the progression of type 2 diabetes or merely a side effect of the disease remains unclear. If hIAPP aggregation into toxic amyloid is on-path for developing type 2 diabetes in humans, islet amyloid polypeptide (IAPP) aggregation would likely need to play a similar role within other organisms known to develop the disease. In this work, we compared the aggregation potential and cellular toxicity of full-length IAPP from several diabetic and nondiabetic organisms whose aggregation propensities had not yet been determined for full-length IAPP.


Asunto(s)
Polipéptido Amiloide de los Islotes Pancreáticos/genética , Animales , Gatos , Bovinos , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Pollos , Perros , Relación Dosis-Respuesta a Droga , Cobayas , Humanos , Polipéptido Amiloide de los Islotes Pancreáticos/química , Polipéptido Amiloide de los Islotes Pancreáticos/farmacología , Octodon , Mapaches , Ratas , Relación Estructura-Actividad , Porcinos
3.
Anal Chem ; 90(22): 13572-13579, 2018 11 20.
Artículo en Inglés | MEDLINE | ID: mdl-30339359

RESUMEN

Hydrogel microparticles have been extensively used in the field of medical diagnostics for detecting targets ranging from proteins to nucleic acids. However, little is known about how the shape of hydrogel particles impacts the signal from a bioassay. In this article, we analyze the flux into porous hydrogel particles to develop scaling laws for the signal from a point-of-care bioassay. The signal can be increased by increasing the ratio of the surface area of the hydrogel particle to the two-dimensional projected imaging area used for analysis. We show that adding internal surface area to hydrogel particles increases the assay signal in a biotin-streptavidin bioassay. We also demonstrate the application of this technique to a protein-based assay for thyroid-stimulating hormone, reducing the limit of detection of the assay sixfold by changing particle shape. We anticipate that these strategies can be used broadly to optimize hydrogel-based systems for point-of-care diagnostics.


Asunto(s)
Bioensayo/métodos , Hidrogeles , Límite de Detección , Sistemas de Atención de Punto , Reproducibilidad de los Resultados , Tirotropina/análisis
4.
Anal Chem ; 88(6): 3075-81, 2016 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-26863201

RESUMEN

In recent years, microRNAs (miRNAs) have emerged as promising diagnostic markers because of their unique dysregulation patterns under various disease conditions and high stability in biological fluids. However, current methods of analyzing miRNA levels typically require RNA isolation, which is cumbersome and time-consuming. To achieve high-throughput and accurate miRNA profiling, this study eliminates the need for purification steps by detecting miRNA directly from raw cellular lysate using nonfouling polyethylene glycol microparticles. In contrast to recent studies on direct miRNA measurements from cell lysate, our hydrogel-based system provides high-confidence quantification with robust performance. The lysis buffer for the assay was optimized to maximize reaction and labeling efficiency, and this assay has a low limit of detection (<1000 cells) without target amplification. Additionally, the capability for multiplexing was demonstrated through analyzing the levels of three endogenous miRNAs in 3T3 cell lysate. This versatile platform holds great potential for rapid and reliable direct miRNA quantification in complex media, and can be further extended to single-cell analysis by exploiting the flexibility and scalability of our system.


Asunto(s)
Hidrogeles , MicroARNs/análisis , Límite de Detección , Microesferas
5.
NPJ Vaccines ; 9(1): 29, 2024 Feb 10.
Artículo en Inglés | MEDLINE | ID: mdl-38341502

RESUMEN

New strategies are needed to reduce the incidence of malaria, and promising approaches include vaccines targeting the circumsporozoite protein (CSP). To improve upon the malaria vaccine, RTS,S/AS01, it is essential to standardize preclinical assays to measure the potency of next-generation vaccines against this benchmark. We focus on RTS,S/AS01-induced antibody responses and functional activity in conjunction with robust statistical analyses. Transgenic Plasmodium berghei sporozoites containing full-length P. falciparum CSP (tgPb-PfCSP) allow two assessments of efficacy: quantitative reduction in liver infection following intravenous challenge, and sterile protection from mosquito bite challenge. Two or three doses of RTS,S/AS01 were given intramuscularly at 3-week intervals, with challenge 2-weeks after the last vaccination. Minimal inter- and intra-assay variability indicates the reproducibility of the methods. Importantly, the range of this model is suitable for screening more potent vaccines. Levels of induced anti-CSP antibody 2A10 equivalency were also associated with activity: 105 µg/mL (95% CI: 68.8, 141) reduced liver infection by 50%, whereas 285 µg/mL (95% CI: 166, 404) is required for 50% sterile protection from mosquito bite challenge. Additionally, the liver burden model was able to differentiate between protected and non-protected human plasma samples from a controlled human malaria infection study, supporting these models' relevance and predictive capability. Comparison in animal models of CSP-based vaccine candidates to RTS,S/AS01 is now possible under well controlled conditions. Assessment of the quality of induced antibodies, likely a determinant of durability of protection in humans, should be possible using these methods.

6.
NPJ Vaccines ; 7(1): 34, 2022 Mar 08.
Artículo en Inglés | MEDLINE | ID: mdl-35260593

RESUMEN

Pre-erythrocytic malaria vaccines that induce high-titer, durable antibody responses can potentially provide protection from infection. Here, we engineered a virus-like particle (VLP)-based vaccine targeting a recently described vulnerable epitope at the N-terminus of the central repeat region of the Plasmodium falciparum circumsporozoite protein that is recognized by the potently inhibitory monoclonal antibody L9 and show that immunization with L9 VLPs induces strong antibody responses that provide protection from blood-stage malaria in a mouse infection model.

7.
SSM Popul Health ; 17: 100952, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-34786449

RESUMEN

The U.S government has historically responded to human, natural and economic disruptions that threaten food insecurity by modifying federally-funded public food programs. The authors conducted a scoping review to identify and summarize available evidence on the efforts of a 20-year period to modify food benefit programs in response to emergencies; describe how food benefit programs interact to support vulnerable populations; identify key facilitators and barriers to effective implementation and impact; and assess relevance of evidence to COVID-19 pandemic. Scoping reviews address broad research questions aimed at mapping key concepts and available evidence in a defined area, and include academic and gray literature and reports from governments and NGOs. This review followed the PRISMA Extension for Scoping Reviews and included a three-stage search strategy. Studies were independently screened for eligibility by two researchers with multiple rounds of review. A content based charting method was used to summarize evidence. More than 2289 documents were identified and screened. After review, 44 documents were analyzed. Only 18% of documents reported program or policy impact data. Additionally, review of 149 policy records from State by State FNS Disaster Assistance Data from Oct 2016-Dec 2020 assessed 96 state specific food policy responses to 72 distinct events. Analysis revealed 53 distinct packages of food policy modifications used in response to crises. This scoping review demonstrates that few studies document the impact on food insecurity of food benefit modifications in response to crises. Most documents present output level details about costs and total number of individuals served. Many documents describe food policy response to crises without providing evaluation of response. Analysis points to SNAP and Child Nutrition Programs as most commonly modified food benefit programs in the wake of U.S. crises. The review concludes with a number of considerations for continued response to the ongoing COVID-19 crisis.

8.
Health Place ; 76: 102843, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35728454

RESUMEN

To explore the presence of predatory food and beverage marketing in different neighborhoods in New York City (NYC), this study describes the methodology of an outdoor environmental scan of the physical environment. The study was conducted in four NYC neighborhoods over a three-week period, in which pairs of trained researchers canvassed designated neighborhoods to document the presence of food and beverage marketing using photographs taken on digital smart phone devices. Commercial areas in the vicinity of NYC Public Schools and NYC Housing Authority campuses located in four neighborhoods with the highest and lowest nutrition related health indicators were studied: South Bronx, Pelham Throggs Neck, Upper West Side, Chelsea/Greenwich Village. Advertisements were coded against 50+ indicators to quantify pertinent variables including the frequency and content of food and beverages advertised and all forms of predatory marketing observed. Comparisons of prevalence and content of food and beverage advertisements and predatory marketing were made across neighborhoods with the highest and lowest health indicators, using chi-squared analysis, and a significance level of p < 0.05. This article demonstrates a disproportionate presence of predatory marketing in low income NYC neighborhoods with negative health outcomes compared to wealthier neighborhoods. Further, this paper demonstrates the benefits and limitations of using an environmental scan methodology to assess predatory food and beverage marketing in a large urban area such as NYC.


Asunto(s)
Bebidas , Alimentos , Publicidad , Humanos , Mercadotecnía/métodos , Ciudad de Nueva York
9.
Biotechnol J ; 17(7): e2100304, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-34505742

RESUMEN

The programmable nature of sequence-specific targeting by CRISPR-Cas nucleases has revolutionized a wide range of genomic applications and is now emerging as a method for nucleic acid detection. We explore how the diversity of CRISPR systems and their fundamental mechanisms have given rise to a wave of new methods for target recognition and readout. These cross-disciplinary advances found at the intersection of CRISPR biology and engineering have led to the ability to rapidly generate solutions for emerging global challenges like the COVID-19 pandemic. We further discuss the advances and potential for CRISPR-based detection to have an impact across a continuum of diagnostic applications.


Asunto(s)
COVID-19 , Sistemas CRISPR-Cas , COVID-19/diagnóstico , Sistemas CRISPR-Cas/genética , Endonucleasas/metabolismo , Edición Génica/métodos , Humanos , Pandemias
10.
Antonie Van Leeuwenhoek ; 100(3): 399-404, 2011 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-21638112

RESUMEN

This study reports a novel study of marine biofilm formation comprising aerobic and anaerobic bacteria. Samples of quartz and feldspar, minerals commonly found on the earth, were suspended 5 m deep in the North Sea off the east coast of St. Andrews, Scotland for 5 weeks. The assemblage of organisms attached to these stones was cultivated under aerobic and anaerobic conditions in the laboratory. Bacteria isolated on Marine Agar 2216 were all Gram-negative and identified to genus level by sequencing the gene encoding 16S rRNA. Colwellia, Maribacter, Pseudoaltermonas and Shewanella were observed in aerobically-grown cultures while Vibrio was found to be present in both aerobic and anaerobic cultures. The obligate anaerobic bacterium Psychrilyobacter atlanticus, a recently defined genus, was identified as a close relative of isolates grown anaerobically. The results provide valuable information as to the main players that attach and form de novo biofilms on common minerals in sea water.


Asunto(s)
Bacterias Aerobias/aislamiento & purificación , Bacterias Aerobias/fisiología , Bacterias Anaerobias/aislamiento & purificación , Bacterias Anaerobias/fisiología , Biopelículas , Agua de Mar/microbiología , Bacterias Aerobias/clasificación , Bacterias Aerobias/genética , Bacterias Anaerobias/clasificación , Bacterias Anaerobias/genética , ADN Bacteriano/genética , Datos de Secuencia Molecular , Filogenia , ARN Ribosómico 16S/genética , Escocia
11.
Harefuah ; 150(11): 837-41, 876, 2011 Nov.
Artículo en Hebreo | MEDLINE | ID: mdl-22428203

RESUMEN

BACKGROUND: Human papillomavirus (HPV) is recognized as the absolute cause of cervical cancer and is found in 99% of the Lesions. HPV 16 and 18 are detected in 70% of the cases. Two vaccines against HPV 16 and 18 were approved for use in Israel in recent years. PURPOSE: To determine the prevalence of human papillomavirus (HPV) in women with invasive cervical cancer in the Haifa district, and to see if the vaccine is suitable for our population. METHODS: The study population included 65 women from the Haifa District who were diagnosed with invasive cervical cancer in the Cervix Clinic of Carmel Medical Center. Samples for HPV typing were obtained during the evaluation of those patients. DNA was extracted from brush samples and HPV genotype was determined by nested-PCR followed by sequencing. RESULTS: Out of 65 patients with cervical carcinoma, 64 were found positive for HPV. The main HPV types in our patients were HPV 16 in 53.8% of the patients, HPV 18 in 12.3% of the patients and HPV type 45 in 13.8% of the patients. HPV type 33 was found in 4.6% of the patients, and HPV types 31 and 66 in 3.1% of the patients. Each of HPV types 54, 56, 58 and 59 were found in one patient. The main complaint was postmenopausal bleeding or menometrorrhagia in 24 patients (36.9%), post coital bleeding in 18 patients (27.7%) and 14 patients (21.5%) were evaluated due to an abnormal cytological smear Squamous cell carcinoma was diagnosed in 83% of the patients and cervical adenocarcinoma in 15.1% of them. CONCLUSIONS: The prevalence of HPV types in Haifa district is similar to world prevalence of HPV's, where HPV 16 and 18 cause 66.1% of cervical cancer, while in our study HPV45 and HPV 66 were found in higher proportions of cases than reported worldwide. In our population the vaccine against HPV 16/18 can prevent almost 70% of cases of cervical cancer, but a multicenter study should be performed in order to obtain larger numbers.


Asunto(s)
ADN Viral/análisis , Papillomaviridae/aislamiento & purificación , Infecciones por Papillomavirus/virología , Neoplasias del Cuello Uterino/virología , Adenocarcinoma/patología , Adenocarcinoma/virología , Adulto , Anciano , Anciano de 80 o más Años , Carcinoma de Células Escamosas/patología , Carcinoma de Células Escamosas/virología , Femenino , Genotipo , Humanos , Israel/epidemiología , Persona de Mediana Edad , Papillomaviridae/clasificación , Infecciones por Papillomavirus/epidemiología , Reacción en Cadena de la Polimerasa , Prevalencia , Análisis de Secuencia de ADN , Neoplasias del Cuello Uterino/patología
12.
ACS Sens ; 6(1): 203-211, 2021 01 22.
Artículo en Inglés | MEDLINE | ID: mdl-33351603

RESUMEN

There has been an increasing and urgent demand to develop nucleic acid bioassays which not only offer high analytical performance but which are also amenable with point-of-care testing. Hydrogels present a versatile class of materials with biocompatible antifouling properties and the ability to be engineered for a range of advanced sensing applications. Fibrous substrates like nitrocellulose offer low-cost and durable platforms to run complex bioassays while enabling portability and ease of handling. We demonstrate herein the ability to synergistically combine these two materials into a portable biosensing platform by leveraging projection lithography. We demonstrate the direct polymerization of hydrogel sensing motifs within a range of fibrous substrates with precise control over their shape, size, location, and functionality. Spatial encoding of the hydrogel motifs enables the multiplex detection of multiple biomarkers on the same test. As a proof-of-concept, we apply the platform to the detection of microRNA, an emerging class of circulating biomarkers with promising potential for early diagnosis and monitoring of cancer. The assay offers a large dynamic range (over three orders of magnitude), high sensitivity (limit of detection of 2.5 amol), as well as versatility and ease of handling. Finally, the bioassay is validated using real biological samples, namely, total RNA extracted from the sera of late-stage breast cancer patients, demonstrating its utility and compatibility with clinical biosensing applications.


Asunto(s)
Hidrogeles , MicroARNs , Bioensayo , Biomarcadores , Humanos
13.
ACS Omega ; 6(10): 6571-6581, 2021 Mar 16.
Artículo en Inglés | MEDLINE | ID: mdl-33748569

RESUMEN

DNA and RNA have been measured with many techniques but often with relatively long analysis times. In this study, we utilize fast-scan cyclic voltammetry (FSCV) for the subsecond codetection of adenine, guanine, and cytosine, first as free nucleosides, and then within custom synthesized oligos, plasmid DNA, and RNA from the nematode Caenorhabditis elegans. Previous studies have shown the detection of adenosine and guanosine with FSCV with high spatiotemporal resolution, while we have extended the assay to include cytidine and adenine, guanine, and cytosine in RNA and single- and double-stranded DNA (ssDNA and dSDNA). We find that FSCV testing has a higher sensitivity and yields higher peak oxidative currents when detecting shorter oligonucleotides and ssDNA samples at equivalent nucleobase concentrations. This is consistent with an electrostatic repulsion from negatively charged oxide groups on the surface of the carbon fiber microelectrode (CFME), the negative holding potential, and the negatively charged phosphate backbone. Moreover, as opposed to dsDNA, ssDNA nucleobases are not hydrogen-bonded to one another and thus are free to adsorb onto the surface of the carbon electrode. We also demonstrate that the simultaneous determination of nucleobases is not masked even in biologically complex serum samples. This is the first report demonstrating that FSCV, when used with CFMEs, is able to codetect nucleobases when polymerized into DNA or RNA and could potentially pave the way for future uses in clinical, diagnostic, or research applications.

14.
Arthritis Care Res (Hoboken) ; 73(11): 1672-1677, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-32702144

RESUMEN

OBJECTIVE: To examine glucocorticoid-sparing immunomodulatory medication use in youth with systemic lupus erythematosus (SLE) during their first year of care. METHODS: We conducted a retrospective cohort study using administrative claims for 2000 to 2013 from Clinformatics DataMart for youth ages 10-24 years with an incident diagnosis of SLE (≥3 International Classification of Diseases, Ninth Revision codes for SLE [710.0], each >30 days apart). We determined the proportion of subjects filling a prescription for immunomodulatory medications within 12 months of the first SLE code (index date). We used multivariable regression to examine associations between demographic/disease factors and time to prescription fill in the first year, and also between prescription fill at any time after the index date. RESULTS: We identified 532 youth with an incident SLE diagnosis, of which 413 (78%) had a glucocorticoid-sparing immunomodulatory prescription fill in the first year. Prescriptions for hydroxychloroquine and immunosuppressants were filled in the first year by 366 youth (69%) and by 182 (34%), respectively. Those with adult-onset (versus childhood-onset) disease were less likely to fill an immunomodulatory medication by 12 months. No other statistically significant associations were found, although there was increasing likelihood of immunomodulatory medication fills with each subsequent calendar year. CONCLUSION: Among youth with newly diagnosed SLE, hydroxychloroquine use is prevalent although not universal, and prescription immunosuppressant use is notably low during the first year of care. Further research is needed to identify factors contributing to suboptimal immunomodulatory medication use during the first year of care.


Asunto(s)
Antirreumáticos/uso terapéutico , Hidroxicloroquina/uso terapéutico , Inmunosupresores/uso terapéutico , Lupus Eritematoso Sistémico/tratamiento farmacológico , Reclamos Administrativos en el Cuidado de la Salud , Adolescente , Niño , Prescripciones de Medicamentos , Utilización de Medicamentos , Femenino , Humanos , Inmunosupresores/efectos adversos , Lupus Eritematoso Sistémico/diagnóstico , Lupus Eritematoso Sistémico/inmunología , Masculino , Pautas de la Práctica en Medicina , Estudios Retrospectivos , Factores de Tiempo , Adulto Joven
15.
Am J Physiol Cell Physiol ; 298(4): C942-51, 2010 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-20071690

RESUMEN

Detachment of endothelial cells (ECs) from the extracellular matrix (ECM) is required not only for angiogenesis, but also for EC apoptosis. Matrix metalloproteinase (MMP)-2 plays a major role in the degradation of the ECM, supporting an essential role for this enzyme in both survival (angiogenesis) and death of ECs. Our aim was to study these seemingly paradoxical effects of MMP-2. We rationalized that inhibiting apoptosis would drive MMP-2 toward a prosurvival activity, clarifying the mechanisms involved. By employing specific inhibitors to two major apoptotic pathways in ECs, caspases and p38 MAPK (p38), we demonstrated that they differently affected EC behavior as well as MMP-2 expression. The p38 pathway appears to enhance MMP-2 synthesis, its partial ("intermediate") and its full activation, probably via membrane type (MT)1-MMP, while caspases enhance MMP-2 synthesis and full activation but reduce MT1-MMP and MMP-2 intermediate form. Evaluation of the reciprocal influences of MMP-2 on ECs showed that the intermediate form supported survival and migration, and the fully active form led to cell death. In addition, a pro- and intermediate form-rich environment, even in the presence of the fully active form, exerted protective effects. Thus the seemingly conflicting effects of MMP-2 on EC survival may be explained by the ratio between the MMP-2 activation forms. A regulatory loop between active MMP-2 and p38 but not between MMP-2 and caspases was also observed, suggesting that MMP-2 is downstream to caspases where it serves as an "exterminator" molecule. Altogether, modification of caspase and p38 pathways, via changes of local MMP-2, affect survival and angiogenic steps in ECs.


Asunto(s)
Apoptosis/fisiología , Células Endoteliales/fisiología , Metaloproteinasa 2 de la Matriz/metabolismo , Clorometilcetonas de Aminoácidos/farmacología , Apoptosis/efectos de los fármacos , Caspasa 3/genética , Caspasa 3/metabolismo , Inhibidores de Caspasas , Movimiento Celular/fisiología , Forma de la Célula , Células Cultivadas , Células Endoteliales/citología , Células Endoteliales/efectos de los fármacos , Inhibidores Enzimáticos/farmacología , Matriz Extracelular/metabolismo , Humanos , Imidazoles/farmacología , Metaloproteinasa 2 de la Matriz/genética , Piridinas/farmacología , Transducción de Señal/efectos de los fármacos , Transducción de Señal/fisiología , Proteínas Quinasas p38 Activadas por Mitógenos/antagonistas & inhibidores , Proteínas Quinasas p38 Activadas por Mitógenos/genética , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo
16.
Biomicrofluidics ; 11(6): 064105, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-29204246

RESUMEN

Due to the critical roles that platelets play in thrombosis during many biological and pathological events, altered platelet function may be a key contributor to altered hemostasis, leading to both thrombotic and hemorrhagic complications. Platelet adhesion at arterial shear rates occurs through binding to von Willebrand Factor via the glycoprotein (GP) GPIb receptor. GPIb binding can induce platelet activation distinguishable by P-selectin (CD62P) surface expression and αIIbß3 activation, resulting in platelet aggregation and formation of the primary hemostatic plug to stop bleeding. Previous studies have used cone and plate viscometers to examine pathologic blood flow conditions, applied shear rates that are relatively low, and examined exposure times that are orders of magnitude longer compared to conditions present in ventricular assist devices, mechanical heart valves, or pathologic states such as stenotic arteries. Here, we evaluate the effect of short exposure to high shear on granule release and receptor shedding utilizing a constricted microfluidic device in conjunction with flow cytometry and enzyme-linked immunosorbent assay. In this study, platelets were first perfused through microfluidic channels capable of producing shear rates of 80 000-100 000 s-1 for exposure times of 0-73 ms. We investigated platelet activation by measuring the expression level of CD62P (soluble and surface expressed), platelet factor 4 (PF4), and beta-thromboglobulin (ßTG). In addition, we measured potential platelet receptor shedding of GPVI and GPIb using flow cytometry. The results showed that a single pass to high shear with short exposure times (milliseconds) had no effect on the levels of CD62P, GPVI and GPIb, or on the release of alpha granule content (PF4, ßTG, and sP-selectin).

17.
Circ Res ; 90(7): 784-91, 2002 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-11964371

RESUMEN

Among the consequences resulting from the exposure of endothelial cells (ECs) to ischemia/reperfusion is angiogenesis, involving degradation of vascular basement membrane and extracellular matrix. Matrix metalloproteinase (MMP)-2, a member of the MMP family, partakes in this process. MMP-2, secreted as a proenzyme, undergoes activation through interaction with membrane type (MT)1-MMP and the endogenous tissue inhibitor of MMPs (TIMP)-2. Although hypoxia and reoxygenation (H/R) are major constituents of ischemia/reperfusion processes, their direct effects on endothelial MMP-2 have been scarcely investigated. This study examined the in vitro effects of H/R on human macrovascular ECs (EAhy 926). The level of MMP-2 mRNA (Northern blot) and protein (zymography, ELISA) and the mRNA of its activator (MT1-MMP) and inhibitor (TIMP-2) were analyzed. Short (6-hour) hypoxia inhibited the mRNA expression of MMP-2, MT1-MMP, and TIMP-2, culminating in reduced latent and active MMP-2 protein. Prolonged (24-hour) hypoxia further suppressed MT1-MMP and TIMP-2 mRNA, whereas it enhanced MMP-2 mRNA and enzyme secretion (after 48-hour hypoxia). Reoxygenation did not influence the inhibited TIMP-2 but upregulated MMP-2 and MT1-MMP mRNA expression, leading to enhanced secretion of active MMP-2 protein. These results demonstrate H/R-mediated modulation of EC MMP-2 at both transcriptional and posttranscriptional levels. Prolonged hypoxia of ECs appears to enhance MMP-2 production and secretion, whereas reoxygenation further increases its level. These H/R-mediated effects on MMPs have the potential of enabling EC migration and possible angiogenesis.


Asunto(s)
Hipoxia de la Célula/fisiología , Endotelio Vascular/metabolismo , Metaloproteinasa 2 de la Matriz/metabolismo , Oxígeno/farmacología , Northern Blotting , Línea Celular , Supervivencia Celular/efectos de los fármacos , Supervivencia Celular/fisiología , Endotelio Vascular/citología , Activación Enzimática/fisiología , Ensayo de Inmunoadsorción Enzimática , Humanos , Metaloproteinasa 2 de la Matriz/genética , Metaloproteinasas de la Matriz Asociadas a la Membrana , Metaloendopeptidasas/genética , Metaloendopeptidasas/metabolismo , Microcirculación/metabolismo , Oxígeno/metabolismo , Estabilidad del ARN/efectos de los fármacos , Estabilidad del ARN/fisiología , ARN Mensajero/metabolismo , Inhibidor Tisular de Metaloproteinasa-2/genética , Inhibidor Tisular de Metaloproteinasa-2/metabolismo , Regulación hacia Arriba/efectos de los fármacos
18.
J Neuroimmunol ; 163(1-2): 157-64, 2005 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-15885317

RESUMEN

T helper subsets, Th1 and Th2, which are associated with different types of immune reactions, are distinguished by their cytokines' profiles and expression of different chemokine receptors, that may differentially influence their migratory capacity. The present study examined the expression of matrix metalloproteinases, (MMP)-2 and MMP-9, by the two CD4+ Th cell subsets and the role of these proteases in their migration. We observed that migration of CD4+ T cells is dependent on the gelatinases, and that the migratory capacity of Th1 is higher than Th2 cells. In addition, Th1 in comparison to Th2 cells, from both human (healthy subjects and multiple sclerosis (MS) patients) as well as from murine origin, secrete higher levels of MMP-2 and MMP-9. These novel findings contribute to the understanding of the physiological Th1 and Th2 immune responses as well as the enhanced Th1 reactivity in immune-mediated diseases, such as MS, in which enhanced levels of MMP-2 and MMP-9 are associated with disease processes.


Asunto(s)
Regulación Enzimológica de la Expresión Génica/inmunología , Metaloproteinasa 2 de la Matriz/biosíntesis , Metaloproteinasa 9 de la Matriz/biosíntesis , Células TH1/enzimología , Células Th2/enzimología , Adulto , Animales , Movimiento Celular/inmunología , Células Cultivadas , Células Clonales , Humanos , Metaloproteinasa 2 de la Matriz/metabolismo , Metaloproteinasa 9 de la Matriz/metabolismo , Ratones , Ratones Endogámicos AKR , Ratones Transgénicos , Persona de Mediana Edad , Esclerosis Múltiple Recurrente-Remitente/enzimología , Esclerosis Múltiple Recurrente-Remitente/inmunología , Esclerosis Múltiple Recurrente-Remitente/patología , Células TH1/citología , Células TH1/metabolismo , Células Th2/citología , Células Th2/metabolismo
19.
J Neuroimmunol ; 131(1-2): 191-200, 2002 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-12458052

RESUMEN

Recent findings have implicated the activity of matrix metalloproteinases (MMPs) in the pathogenesis of multiple sclerosis (MS), while in vivo interferon (IFN)-beta treatment was demonstrated to suppress MMPs. In the present study, the effects mediated by IFN-gamma and IFN-beta on the mRNA and protein expression of MMP-2, its physiological activator, MT1-MMP and its endogenous inhibitor, TIMP-2, by monocytes were evaluated in vitro. The results point to the significance of IFNs in modulating MMPs/tissue inhibitors of MMPs (TIMPs) expression, and support the possibility that the therapeutic effects of IFN-beta may be, in part, due to induction of a shift from "pro-" to "anti-proteolytic" pattern of MMPs and TIMPs expression.


Asunto(s)
Interferón beta/farmacología , Interferón gamma/farmacología , Metaloproteinasas de la Matriz/biosíntesis , Monocitos/enzimología , Inhibidor Tisular de Metaloproteinasa-2/biosíntesis , Relación Dosis-Respuesta a Droga , Regulación de la Expresión Génica , Humanos , Metaloproteinasa 2 de la Matriz/biosíntesis , Metaloproteinasa 2 de la Matriz/genética , Metaloproteinasas de la Matriz Asociadas a la Membrana , Metaloendopeptidasas/biosíntesis , Metaloendopeptidasas/genética , Monocitos/efectos de los fármacos , Esclerosis Múltiple/enzimología , ARN Mensajero/biosíntesis , Inhibidor Tisular de Metaloproteinasa-2/genética , Transcripción Genética , Células U937
20.
J Neuroimmunol ; 144(1-2): 116-24, 2003 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-14597105

RESUMEN

Reciprocal interactions between T cells and antigen-presenting cells (APCs) within the 'Immunological-Synapse' (IS) govern immune cell autoreactivity in multiple sclerosis (MS). The present study examined the expression of a range of co-stimulatory molecules: CD40, CD54, CD80, CD86 and HLA-DR, on the cell-surface of CD14(+) peripheral blood monocytes (PBM) from relapsing-remitting (RR) and secondary-progressive (SP)-MS patients, prior to and during 1 year of Interferon (IFN)-beta-1a (Rebif(R)) therapy. Prior to treatment, patients from both MS subtypes expressed elevated CD80 and reduced CD40 levels in comparison to controls. CD86 expression was significantly reduced in SP compared to RR patients and controls. IFN-beta therapy led to a significant reduction in the expression of CD54 and CD80 in both groups of patients as well as to elevation of CD40 and CD86 expression in SP patients. These results confirm IFN-mediated modulation of the APC surface within the immunological-synapse and implicate CD80 and CD86 as targets for interventional therapies in MS as well as other Th1-mediated autoimmune diseases.


Asunto(s)
Adyuvantes Inmunológicos/uso terapéutico , Células Presentadoras de Antígenos/inmunología , Comunicación Celular/inmunología , Interferón beta/uso terapéutico , Esclerosis Múltiple Crónica Progresiva/inmunología , Esclerosis Múltiple Crónica Progresiva/terapia , Esclerosis Múltiple Recurrente-Remitente/inmunología , Esclerosis Múltiple Recurrente-Remitente/terapia , Adolescente , Adulto , Células Presentadoras de Antígenos/metabolismo , Antígenos CD/biosíntesis , Antígeno B7-1/biosíntesis , Antígeno B7-2 , Antígenos CD40/biosíntesis , Regulación hacia Abajo/inmunología , Femenino , Citometría de Flujo , Antígenos HLA-DR/biosíntesis , Humanos , Molécula 1 de Adhesión Intercelular/biosíntesis , Interferón beta-1a , Receptores de Lipopolisacáridos/biosíntesis , Masculino , Glicoproteínas de Membrana/biosíntesis , Persona de Mediana Edad , Monocitos/inmunología , Monocitos/metabolismo , Regulación hacia Arriba/inmunología
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