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1.
Int Ophthalmol ; 39(6): 1231-1238, 2019 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-29705893

RESUMEN

PURPOSE: To study microscopic and ultrastructural changes of levator palpebrae superioris (LPS) muscle in congenital ptosis. METHODS: In this prospective observational study, LPS muscle was studied in 77 eyelids with congenital ptosis; 35-simple congenital ptosis (SCP), 12-Marcus Gunn jaw winking phenomenon (MGJWP), and 30-blepharophimosis epicanthus inversus syndrome (BPES). Light microscopy, enzyme histochemistry, immunohistochemistry and electron microscopy were performed, and results were analyzed. RESULTS: Muscle fibers were detected in 83.33% of MGJWP, 22.86% of SCP and 16.67% of BPES eyelids. Fibers were detected significantly more in individuals with moderate ptosis, LPS action > 4 mm, present eyelid crease and eyelid fold. Severe endomysial and perimysial fibrosis was seen significantly more in individuals with MGJWP. Fat infiltration and nuclei internalization were seen in all three groups. The absence of degenerating or regenerating fibers and inflammatory cells, normal staining pattern on immunohistochemistry and absence of accumulation of any abnormal substance were found in all three groups. Abnormal mitochondrial staining pattern was seen occasionally in three groups. On electron microscopy, muscle was detected in 1 SCP eyelid and 8 MGJWP eyelids out of which 4 had myofibrillary disruption. All other eyelids where muscle fibers were not detected had only fibrocollagenous tissue. CONCLUSION: Fibrocollagenous tissue predominated in all the cases, and muscle fibers detected correlated inversely with the severity of ptosis. The absence of degenerating, regenerating fibers and inflammatory cells supported the theory of dysgenesis of muscle. However, internalization of nucleus seen in all the subtypes is a feature favoring dystrophy.


Asunto(s)
Blefaroptosis/fisiopatología , Párpados/fisiopatología , Músculos Oculomotores/fisiopatología , Adulto , Análisis de Varianza , Blefaroptosis/congénito , Colágeno/análisis , Femenino , Humanos , Inmunohistoquímica , Masculino , Proteínas de Microfilamentos/análisis , Microscopía Electrónica , Fibras Musculares Esqueléticas/patología , Fibras Musculares Esqueléticas/ultraestructura , Polisacáridos/análisis , Estudios Prospectivos
3.
Cytopathology ; 26(1): 26-30, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24750348

RESUMEN

OBJECTIVE: The utility of impression cytology in ocular diseases has predominantly been restricted to the diagnosis of dry eye, limbal stem cell deficiency and conjunctival neoplasias. Its role in malignant eyelid lesions remains largely unexplored. Although scrape cytology is more popular for cutaneous lesions, impression cytology, being non-traumatic, has an advantage in small and delicate areas such as the eyelid. The present study has been designed to evaluate its role in the diagnosis and management of malignant eyelid lesions. METHODS: Thirty-two histopathologically proven malignant eyelid lesions diagnosed over a 2-year period, including 13 basal cell carcinomas, 11 sebaceous carcinomas, four squamous cell carcinomas, two malignant melanomas and two poorly differentiated carcinomas, formed the study group. RESULTS: The results of impression cytology were compared with those of histopathology in the study group and with an age- and sex-matched group of benign cases as controls. The sensitivity of impression cytology was 84% (27/32) for the diagnosis of malignancy and 28% (9/32) for categorization of the type of malignancy. CONCLUSIONS: Impression cytology is a simple, useful, non-invasive technique for the detection of malignant ulcerative eyelid lesions. It is especially useful as a follow-up technique for the detection of recurrences.


Asunto(s)
Carcinoma de Células Escamosas/diagnóstico , Citodiagnóstico , Neoplasias de los Párpados/diagnóstico , Melanoma/diagnóstico , Neoplasias de las Glándulas Sebáceas/diagnóstico , Adulto , Anciano , Anciano de 80 o más Años , Carcinoma de Células Escamosas/patología , Neoplasias de los Párpados/patología , Femenino , Humanos , Masculino , Melanoma/patología , Persona de Mediana Edad , Neoplasias de las Glándulas Sebáceas/patología
4.
Br J Dermatol ; 167(3): 583-90, 2012 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-22458737

RESUMEN

BACKGROUND: E-cadherin and ß-catenin are crucial components of the cell-cell adhesion complex. Their loss has often been associated with tumour metastasis and poor clinical outcome. Both loss of E-cadherin at the cell membrane and a stabilizing mutation in CTNNB1 (ß-catenin gene) have been associated with ovarian, colorectal, hepatocellular and nonmelanoma skin cancer, such as squamous and basal cell carcinomas. Absence of E-cadherin may be caused by promoter hypermethylation of the E-cadherin gene (CDH1). OBJECTIVES: To determine the role of E-cadherin promoter hypermethylation and CTNNB1 gene mutation in the aggressive behaviour of sebaceous gland carcinoma of the eyelid. METHODS: Thirty-six cases of sebaceous gland carcinoma were subjected to E-cadherin methylation-specific polymerase chain reaction and mutational analysis for the CTNNB1 gene. E-cadherin and ß-catenin staining was evaluated by immunohistochemistry. Results were correlated with the clinicopathological features of sebaceous gland carcinoma. RESULTS: nMethylation of the E-cadherin promoter region was detected in 72% of eyelid sebaceous gland carcinoma cases and loss of E-cadherin immunostaining in 83%. E-cadherin promoter hypermethylation showed a significant association with the loss of membranous E-cadherin (P = 0·038) and it was of borderline significance with reduced disease-free survival (P = 0·05). It was also found to be associated with advanced age (73%), tumour size ≥ 2 cm (77%), orbital invasion (83%), lymph node metastasis (60%), tumour recurrence (60%) and poor histological differentiation (90%). DNA sequencing revealed no stabilizing ß-catenin gene mutation in sebaceous gland carcinoma. Loss of membranous ß-catenin was observed in 61% cases, which associated significantly with both E-cadherin promoter methylation (P = 0·0262) and loss of E-cadherin membranous localization (P=0·0015). CONCLUSION: Epigenetic inactivation of the E-cadherin gene causes loss of membrane-bound E-cadherin and could contribute to the reduced disease-free survival in eyelid sebaceous gland carcinoma. Mutations in the ß-catenin gene do not seem to be involved in the pathogenesis of eyelid sebaceous gland carcinoma.


Asunto(s)
Cadherinas/genética , Neoplasias de los Párpados/genética , Silenciador del Gen/fisiología , Mutación/genética , Neoplasias de las Glándulas Sebáceas/genética , beta Catenina/genética , Adulto , Anciano , Cadherinas/deficiencia , Cadherinas/metabolismo , Metilación de ADN/genética , Análisis Mutacional de ADN , Epigénesis Genética/genética , Femenino , Humanos , Inmunohistoquímica , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Reacción en Cadena de la Polimerasa , Pronóstico , Regiones Promotoras Genéticas/genética , beta Catenina/metabolismo
5.
Clin Transl Oncol ; 22(9): 1472-1480, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32124242

RESUMEN

BACKGROUND: The role of DNA damage response (DDR) proteins is poorly understood in uveal melanoma. ATR belongs to one of those proteins that induce DDR by arresting the cell cycle which leads to DNA repair. ATR is localized at position 23 on the same chromosome 3 where BAP1 is located at position 21.1 which is a known poor prognostic marker of UM. The aim of our study is to detect the expression of ATR at the protein and RNA levels and determine its prognostic significance. METHODS: Expression of nuclear ATR was investigated on sixty-nine UM patients. Formalin-fixed paraffin-embedded choroidal melanoma samples were taken to evaluate the expression of ATR. Fifty samples were also validated by real-time PCR. Results of both protein and mRNA were then correlated with clinicopathological parameters. To determine the prognostic significance, Kaplan-Meier and multivariate analyses were performed. RESULTS: Loss of ATR protein was seen in 72% cases which was statistically significant with epithelioid cell type (p = 0.005), tumor thickness (p = 0.016), mitotic figures (p = 0.001) and BAP1 loss (p < 0.001). At the transcriptional level loss of ATR was seen in 76% cases which were statistically significant with metastasis (p = 0.046), staging (0.044) and loss of BAP1 (p = 0.022). On multivariate analysis loss of ATR and tumor staging came out to be independent prognostic parameters. CONCLUSION: Our data suggest that ATR might serve as a potential prognostic marker in UM patients and could serve as a potential therapeutic target.


Asunto(s)
Daño del ADN , Melanoma/genética , Neoplasias de la Úvea/genética , Adulto , Proteínas de la Ataxia Telangiectasia Mutada/genética , Proteínas de la Ataxia Telangiectasia Mutada/metabolismo , Biomarcadores de Tumor/genética , Biomarcadores de Tumor/metabolismo , Células Epitelioides/metabolismo , Células Epitelioides/patología , Femenino , Humanos , Masculino , Melanoma/metabolismo , Melanoma/mortalidad , Melanoma/patología , Clasificación del Tumor , Proteínas Supresoras de Tumor/genética , Proteínas Supresoras de Tumor/metabolismo , Ubiquitina Tiolesterasa/genética , Ubiquitina Tiolesterasa/metabolismo , Neoplasias de la Úvea/metabolismo , Neoplasias de la Úvea/mortalidad , Neoplasias de la Úvea/patología
6.
Indian J Ophthalmol ; 66(3): 383-388, 2018 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-29480247

RESUMEN

PURPOSE: To study the features of upper eyelid in healthy individual and different types of congenital ptosis in the Indian population using ultrasound biomicroscopy (UBM). METHODS: This was a prospective observational study at a tertiary care center. Eyelid structure of healthy individuals with no eyelid abnormalities (n = 19); simple congenital ptosis (n = 33) cases; Marcus Gunn jaw-winking ptosis (MGJWP, n = 7) cases, and blepharophimosis-ptosis-epicanthus inversus syndrome (BPES, n = 20) cases were studied on a vertical UBM scan using 50-MHz probe. Lid-thickness, tarsal-thickness, orbicularis oculi and levator-Muller-orbital septum-conjunctival (LMSC) complex were measured in primary gaze. Comparison was made between four groups and results were statistically analyzed using ANOVA test. In normal individuals, LMSC measurements were repeated in down-gaze imaging. RESULTS: Skin with subcutaneous tissue, LMSC complex and pre-aponeurotic fat-pad appeared echodense while orbicularis oculi and tarsus appeared echolucent. In primary gaze, mean thickness (± standard deviation) of the eyelid, tarsus, orbicularis oculi and LMSC, respectively, were: 1.612 ± 0.205, 0.907 ± 0.098, 0.336 ± 0.083, and 0.785 ± 0.135 mm in normal individual. LMSC showed 46.64% increase in thickness on down-gaze. The mean eyelid thickness and LMSC were thicker in MGJWP and BPES as compared to normal. In different types of congenital ptosis cases, various patterns of UBM imaging were observed. CONCLUSION: UBM allows noninvasive imaging of eyelid structures with good anatomical correspondence in normal eyelids and study the structural alterations of eyelids in different types of congenital ptosis. UBM can be used to highlight the anatomical difference in normal eyelids that may help modify the surgery for better cosmetic outcomes. Furthermore, it has the potential to be used in preoperative evaluation and operative planning in certain types of acquired ptosis, which needs to be evaluated.


Asunto(s)
Blefarofimosis/diagnóstico por imagen , Blefaroptosis/diagnóstico por imagen , Párpados/diagnóstico por imagen , Cardiopatías Congénitas/diagnóstico por imagen , Anomalías Maxilomandibulares/diagnóstico por imagen , Microscopía Acústica , Enfermedades del Sistema Nervioso/diagnóstico por imagen , Anomalías Cutáneas/diagnóstico por imagen , Anomalías Urogenitales/diagnóstico por imagen , Adolescente , Adulto , Pueblo Asiatico/etnología , Blefarofimosis/etnología , Blefaroptosis/etnología , Niño , Femenino , Voluntarios Sanos , Cardiopatías Congénitas/etnología , Humanos , India , Anomalías Maxilomandibulares/etnología , Masculino , Enfermedades del Sistema Nervioso/etnología , Estudios Prospectivos , Reflejo Anormal , Anomalías Cutáneas/etnología , Anomalías Urogenitales/etnología , Adulto Joven
7.
J Clin Invest ; 79(6): 1874-8, 1987 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-3034984

RESUMEN

Inhibition of Factor VIIa-tissue factor activity by a plasma component(s) that requires factor Xa has been described recently. In this communication, we have developed a specific radiometric assay (which utilizes 3H-Factor IX and is sensitive to less than 1% of plasma level) for this inhibitor and have measured its activity in various disease states. Strikingly, the levels of this inhibitor were found to be normal in patients with advanced chronic hepatocellular disease but low in patients with disseminated intravascular coagulation (DIC). When endotoxin was used to induce DIC in rabbits, the levels of this inhibitor fell by 25-90%. Human umbilical vein endothelial cells (HUVE), bovine pulmonary artery endothelial cells, and a human hepatoma cell line (HepG2) all synthesized and secreted this inhibitor, whereas a promyelocytic cell line (HL-60) did not and a monocytic cell line (U937) appears to synthesize only small amounts. When ammonium sulfate-fractionated human plasma and serum-free conditioned media from both HUVE and HepG2 cells were electrophoresed on sodium dodecyl sulfate acrylamide gels, two activity peaks corresponding to Mr approximately 45,000 and Mr approximately 33,000 were eluted in each case. These observations suggest that (a) the inhibitor is consumed in DIC and that (b) endothelial cells (or other cells) synthesize sufficient amounts of this inhibitor in vivo to compensate for any decreased production by liver cells.


Asunto(s)
Coagulación Intravascular Diseminada/sangre , Factor VII/antagonistas & inhibidores , Hepatopatías/sangre , Tromboplastina/antagonistas & inhibidores , Animales , Carcinoma Hepatocelular/patología , Bovinos , Células Cultivadas , Enfermedad Crónica , Factor VIIa , Humanos , Recién Nacido , Leucemia Mieloide Aguda/patología , Neoplasias Hepáticas , Linfoma de Células B Grandes Difuso/patología , Arteria Pulmonar , Conejos , Venas Umbilicales/citología
8.
J Thromb Haemost ; 5(7): 1493-9, 2007 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-17470199

RESUMEN

BACKGROUND: Monocytes are critical cells in initiating physiologic and/or pathologic tissue factor (TF)-induced intravascular and extravascular coagulation. Monocytes constitutively express small amounts of TF and tissue factor pathway inhibitor (TFPI). Non-adherent lipopolysaccharide (LPS)-stimulated monocytes express significant amounts of TF; however, increased expression of TFPI by these cells is controversial. Further, whether fibronectin-adherent monocytes (mimicking conditions in the extravascular space) express sufficient TFPI to inhibit TF-procoagulant activity (PCA) is unknown. OBJECTIVE: To compare TF and TFPI expression by fibronectin-adherent and LPS-stimulated non-adherent monocytes. METHODS: Monocytes were isolated from normal peripheral blood, adhered to fibronectin or stimulated with lipopolysaccharide (LPS) under non-adherent conditions and examined for expression of TF and TFPI using quantitative real-time reverse transcription-polymerase chain reaction (RT-PCR), ELISA and factor X (FX) activation. RESULTS: Under LPS-free conditions, the fibronectin-adherent monocyte TF mRNA, antigen and activity were markedly upregulated. Notably, cell and microparticle (MP)-associated TF and alternatively spliced TF (asTF) were all upregulated. TFPI mRNA and antigen were also upregulated in the fibronectin-adherent monocytes, which significantly inhibited TF-PCA. TFPI mRNAs for both alpha and beta forms were detected. The peak in TFPI activity occurred in tandem with the peak in TF-PCA. In contrast, LPS-stimulated monocytes, which expressed cell and MP-associated TF and asTF, demonstrated only minimal expression of TFPI as determined by mRNA, antigen or inhibition of TF activity. CONCLUSION: Both LPS-stimulated and fibronectin-adherent monocytes demonstrate a procoagulant phenotype by expressing TF but only fibronectin-adherent monocytes express significant amounts of TFPI to control thrombin generation and fibrin formation in the context of extravascular space.


Asunto(s)
Lipoproteínas/metabolismo , Monocitos/metabolismo , Tromboplastina/metabolismo , Secuencia de Bases , Adhesión Celular , Cartilla de ADN/genética , Fibronectinas/metabolismo , Humanos , Técnicas In Vitro , Lipopolisacáridos/toxicidad , Lipoproteínas/genética , Monocitos/efectos de los fármacos , Monocitos/patología , ARN Mensajero/genética , ARN Mensajero/metabolismo , Tromboplastina/genética
9.
J Thromb Haemost ; 14(12): 2509-2523, 2016 12.
Artículo en Inglés | MEDLINE | ID: mdl-27797450

RESUMEN

Essentials Current antifibrinolytics - aminocaproic acid and tranexamic acid-can cause seizures or renal injury. KD1L17R -KT , aprotinin and tranexamic acid were tested in a modified mouse tail-amputation model. S2'-subsite variations between human and mouse factor XIa result in vastly different inhibition profiles. KD1L17R -KT reduces blood loss and D-dimer levels in mouse with unobserved seizures or renal injury. SUMMARY: Background Using tissue factor pathway inhibitor (TFPI)-2 Kunitz domain1 (KD1), we obtained a bifunctional antifibrinolytic molecule (KD1L17R -KT ) with C-terminal lysine (kringle domain binding) and P2'-residue arginine (improved specificity towards plasmin). KD1L17R -KT strongly inhibited human plasmin (hPm), with no inhibition of human kallikrein (hKLK) or factor XIa (hXIa). Furthermore, KD1L17R -KT reduced blood loss comparable to aprotinin in a mouse liver-laceration model of organ hemorrhage. However, effectiveness of these antifibrinolytic agents in a model of hemorrhage mimicking extremity trauma and their inhibition efficiencies for mouse enzymes (mPm, mKLK or mXIa) remain to be determined. Objective To determine potential differences in inhibition constants of various antifibrinolytic agents against mouse and human enzymes and test their effectiveness in a modified mouse tail-amputation hemorrhage model. Methods/Results Unexpectedly, mXIa was inhibited with ~ 17-fold increased affinity by aprotinin (Ki ~ 20 nm) and with measurable affinity for KD1L17R -KT (Ki ~ 3 µm); in contrast, KD1WT -VT inhibited hXIa or mXIa with similar affinity. Compared with hPm, mPm had ~ 3-fold reduced affinity, whereas species specificity for hKLK and mKLK was comparable for each inhibitor. S2'-subsite variations largely accounted for the observed differences. KD1L17R -KT and aprotinin were more effective than KD1WT -VT or tranexamic acid in inhibiting tPA-induced mouse plasma clot lysis. Further, KD1L17R -KT was more effective than KD1WT -VT and was comparable to aprotinin and tranexamic acid in reducing blood loss and D-dimer levels in the mouse tail-amputation model. Conclusions Inhibitor potencies differ between antifibrinolytic agents against human and mouse enzymes. KD1L17R -KT is effective in reducing blood loss in a tail-amputation model that mimics extremity injury.


Asunto(s)
Factor XIa/genética , Fibrinolisina/genética , Glicoproteínas/química , Calicreínas/genética , Animales , Antifibrinolíticos , Aprotinina/química , Bovinos , Productos de Degradación de Fibrina-Fibrinógeno/química , Fibrinólisis , Glicoproteínas/genética , Hemorragia , Humanos , Leucina/química , Hígado/metabolismo , Ratones , Modelos Moleculares , Mutación , Péptido Hidrolasas/química , Dominios Proteicos , Convulsiones , Especificidad de la Especie , Ácido Tranexámico/química , Tripsina/química
12.
Thromb Haemost ; 78(1): 471-7, 1997 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-9198199

RESUMEN

Tissue factor pathway of coagulation plays a dominant role during normal haemostasis. Tissue factor pathway inhibitor (TFPI), expressed primarily by the microvascular endothelium, appears to be the major physiologic inhibitor of TF-induced coagulation. TF-initiated coagulation also plays an important role in the pathophysiology of many diseases including coronary thrombosis, sepsis, disseminated intravascular coagulation, stroke, cancer, acute respiratory distress syndrome, and ischemia-reperfusion injury. Several animal studies have found a beneficial effect of anti-TF monoclonal antibodies and, recombinant TFPI in some of the above clinical conditions. rTFPI is presently being used in clinical trials in patients with sepsis and in those following microvascular surgery. This article discusses many of the animal studies addressing inhibition of TF-induced coagulation, as well as potential therapeutic uses of rTFPI in humans.


Asunto(s)
Anticoagulantes/uso terapéutico , Lipoproteínas/uso terapéutico , Animales , Trastornos Cerebrovasculares/tratamiento farmacológico , Enfermedad Coronaria/tratamiento farmacológico , Humanos , Lipoproteínas/biosíntesis , Proteínas Recombinantes/uso terapéutico , Daño por Reperfusión/tratamiento farmacológico , Sepsis/tratamiento farmacológico , Trombosis/tratamiento farmacológico
13.
Thromb Haemost ; 73(5): 873-5, 1995 May.
Artículo en Inglés | MEDLINE | ID: mdl-7482419

RESUMEN

Under normal conditions, TFPI expression is restricted to megakaryocytes and the endothelium of the microvasculature. It is not synthesized by normal hepatocytes or by the endothelium of larger vessels. In contrast, endothelium and peripheral blood cells do not express tissue factor under normal conditions. Expression of tissue factor under normal physiologic conditions is widespread and is localized in areas which are physically separated from the circulating blood. During an inflammatory response, circulating monocytes have been shown to express tissue factor, whereas in general, expression of tissue factor has not been observed in the endothelium. Adherent monocytes/macrophages express both tissue factor and TFPI under pathologic conditions. Whether or not circulating peripheral blood monocytes under inflammatory conditions express TFPI is not known.


Asunto(s)
Inflamación/metabolismo , Lipoproteínas/biosíntesis , Tromboplastina/biosíntesis , Animales , Células Sanguíneas/metabolismo , Células Cultivadas , Citocinas/farmacología , Endotelio Vascular/metabolismo , Regulación de la Expresión Génica/efectos de los fármacos , Genes , Humanos , Inflamación/genética , Lipoproteínas/genética , Hígado/metabolismo , Macrófagos/metabolismo , Megacariocitos/metabolismo , Monocitos/efectos de los fármacos , Monocitos/metabolismo , Especificidad de Órganos , Conformación Proteica , Tromboplastina/química , Tromboplastina/genética
14.
Thromb Haemost ; 82(3): 1047-52, 1999 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-10494762

RESUMEN

Under normal physiologic conditions, tissue factor pathway inhibitor (TFPI) is synthesized primarily by the microvascular endothelium. Using Northern blotting, we studied its transcriptional expression in different organs and compared it with the expression of two other endothelial specific proteins, namely thrombomodulin (TM) and von Willebrand factor (vWF). The order of mRNA expression for each protein was: TFPI-placenta>lung>liver>kidney>heart>skeletal muscle> or =pancreas>brain; TM-heart>pancreas>lung>skeletal muscle>kidney> or =liver>placenta>brain; and vWF-heart>skeletal muscle>pancreas>lung> or =kidney>placenta>brain>liver. Notably, heart expressed TM and vWF mRNA in large amounts and only small amounts of TFPI whereas lung expressed all three mRNAs in significant amounts. Placenta, on the contrary, expressed large amounts of TFPI but only small amounts of TM and vWF mRNAs. Brain by this technique was found to express undetectable amounts of TFPI and TM mRNAs but small amounts of vWF mRNA. The expression of TFPI mRNA in the brain was however detected by RT/PCR and the antigen was localized to the endothelium of microvessels as well as to the astrocytes and oligodendrocytes. Since ultimate expression of proteins is linked to the expression of their mRNAs, our data support a concept that vascular endothelium is made up of phenotypically diverse groups of cells and that endothelial cells of different vascular beds express specific sets of genes that enable them to carry out tissue-specific functions. Importantly, since astrocytes are known to express tissue factor, the TFPI expression by these cells may control coagulation in their microenvironment and their response to injury and inflammation.


Asunto(s)
Lipoproteínas/genética , Trombomodulina/genética , Factor de von Willebrand/genética , Encéfalo/metabolismo , Endotelio Vascular/metabolismo , Femenino , Expresión Génica , Humanos , Inmunohistoquímica , Lipoproteínas/metabolismo , Embarazo , ARN Mensajero/genética , ARN Mensajero/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Distribución Tisular
15.
Thromb Haemost ; 82(6): 1663-72, 1999 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-10613653

RESUMEN

Tissue factor pathway inhibitor (TFPI) plays an important role in regulating tissue factor (TF)-initiated blood coagulation. Since serum stimulation of fibroblasts, vascular smooth muscle cells and cardiac myocytes in culture increases the expression of TF mRNA and antigen (Ag) in these cells, we hypothesized that serum may also induce increased synthesis of TFPI in these cells to regulate the TF-induced extravascular clotting at an injury site. To test this concept, we used primary isolates of the following human cell types - fetal and adult lung fibroblasts, pulmonary and aortic smooth muscle cells, and cardiac myocytes. Serum-stimulation of these cells resulted in an increased expression of TF mRNA and Ag (8 to 10-fold). Upon serum stimulation, expression of TFPI mRNA and Ag was also increased in these cells. However, the increase in TFPI-Ag (6 to 8-fold) was significantly greater than the TFPI mRNA (2 to 3-fold). Notably, increased expression of TFPI persisted after the TF expression had declined. Further, increased synthesis of TFPI initially led to the saturation of heparin-releasable binding sites. TFPI-Ag was detected by Western blotting, 35S-metabolic labeling and activity assays on the conditioned media, heparin-released material from cells, and in cell lysates. TFPI-Ag was also detected by immunofluorescence staining of cells. Actinomycin D partially whereas cycloheximide completely prevented the serum-induced increased expression of TFPI synthesis by these cells, suggesting control primarily at the translational but some at the transcriptional level as well. The Mr of undegraded TFPI in all cases was approximately 45 kDa and was of full length. TFPI synthesized locally by fibroblasts, vascular smooth muscle cells and cardiac myocytes could play a significant role in regulating TF-initiated extravascular clotting especially since plasma TFPI that may be available at the injury site lacks a portion of the carboxyl segment and is a less efficient inhibitor.


Asunto(s)
Fibroblastos/metabolismo , Lipoproteínas/biosíntesis , Músculo Liso Vascular/metabolismo , Miocardio/metabolismo , Adulto , Proteínas Sanguíneas , Células Cultivadas , Técnica del Anticuerpo Fluorescente Indirecta , Humanos
16.
Thromb Haemost ; 86(4): 959-72, 2001 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11686353

RESUMEN

Human tissue factor pathway inhibitor (TFPI) is a modular protein comprised of three Kunitz type domains flanked by peptide segments that are less structured. The sequential order of the elements are: an N-terminal acidic region followed by the first Kunitz domain (K1), a linker region, a second Kunitz domain (K2), a second linker region, the third Kunitz domain (K3), and the C-terminal basic region. The K1 domain inhibits factor VIIa complexed to tissue factor (TF) while the K2 domain inhibits factor Xa. No direct protease inhibiting functions have been demonstrated for the K3 domain. Importantly, the Xa-TFPI complex is a much more potent inhibitor of the VIIa-TF than TFPI by itself. Furthermore, the C-terminal basic region of TFPI is required for rapid physiologic inhibition of coagulation and is needed for the inhibition of smooth muscle cell proliferation. Although a number of additional targets for attachment have been reported, the C-terminal basic region appears to play an important role in binding of TFPI to cell surfaces. A primary site of TFPI synthesis is endothelium and the endothelium-bound TFPI contributes to the antithrombotic potential of the vascular endothelium. Further, increased levels of plasma TFPI under septic conditions may represent endothelial dysfunction. We have proposed that the extravascular cells that synthesize TF also synthesize TFPI providing dual components necessary for the regulation of clotting in their microenvironment. Like the TF synthesis in these cells is augmented by serum, so is the case with the TFPI gene expression. TFPI gene knock out mice reveal embryonic lethality suggesting a possible role of this protein in early development. Since TF-induced coagulation is thought to play a significant role in many disease states, including disseminated intravascular clotting, sepsis, acute lung injury and cancer, recombinant TFPI may be a beneficial therapeutic agent in these disease states to attenuate pathologic clotting. The purpose of this review is to outline recent developments in the field related to the structural specificity and biology of TFPI.


Asunto(s)
Lipoproteínas , Enfermedad Aguda , Secuencia de Aminoácidos , Aminoácidos/química , Síndrome Antifosfolípido/sangre , Coagulación Sanguínea/fisiología , Enfermedades Cardiovasculares/sangre , Endotelio Vascular/metabolismo , Humanos , Lipoproteínas/química , Lipoproteínas/genética , Lipoproteínas/fisiología , Lipoproteínas/uso terapéutico , Enfermedades Pulmonares/sangre , Modelos Biológicos , Modelos Moleculares , Datos de Secuencia Molecular , Metástasis de la Neoplasia , Neoplasias/sangre , Conformación Proteica , Estructura Terciaria de Proteína , Sepsis/sangre , Alineación de Secuencia , Homología de Secuencia de Aminoácido , Relación Estructura-Actividad , Trombofilia/sangre , Trombofilia/tratamiento farmacológico , Tromboplastina/fisiología
17.
Intensive Care Med ; 25(11): 1259-66, 1999 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-10654210

RESUMEN

OBJECTIVE: To determine if the plasma levels of three endothelial-specific proteins, von Willebrand factor (vWF), tissue factor pathway inhibitor (TFPI) and thrombomodulin (TM) may be useful in predicting the development of acute respiratory distress syndrome (ARDS). DESIGN: Blood samples were obtained from normal healthy volunteers and on the first day from patients at risk for ARDS and those with ARDS. Daily sequential measurements of vWF and TFPI were performed in two patients. SETTING: Normal subjects were employees at Saint Louis University Hospital, St. Louis, Missouri. Patients at risk and those with ARDS were patients admitted to the medical and surgical floors and the intensive care units at St. Louis University Hospital. PATIENTS AND PARTICIPANTS: Plasma levels of vWF, TFPI and TM were measured in 27 normals, and on day 1 in 15 patients at risk for ARDS and 18 patients with ARDS from different etiologic factors. MEASUREMENTS AND RESULTS: Plasma levels of vWF were significantly elevated in the at-risk (p < 0.01) and ARDS group (p < 0.001) as compared to normals but did not differ significantly between the two groups (p > 0.05). Plasma levels of TFPI were not significantly different between the normal and the at-risk group (p > 0.05); however, they were significantly elevated in ARDS as compared with at-risk and normal groups (p < 0.001). Levels of TM were significantly increased in the at-risk group as compared to normals (p < 0.01) but were not significantly different from the ARDS group (p > 0.05). Eight patients at risk progressed to develop ARDS. A vWF level of > 300% in patients at risk was 62% sensitive and 71% specific for predicting the development of ARDS with a positive predictive value of only 34%. TFPI levels were normal in 7 of the 8 patients who developed ARDS. A TM level of > 100 ng/ml in patients at risk was 50% sensitive and 57% specific with a positive predictive value of merely 8% for development of ARDS. There was no significant difference in the mean plasma levels of the three proteins on day 1 in patients at risk who developed ARDS as compared with those who did not develop ARDS. There was also no difference in mean plasma levels of the three proteins in patients with ARDS from sepsis as compared with ARDS from other etiologies. Plasma levels of vWF and TFPI correlated significantly. CONCLUSION: Plasma levels of vWF, TFPI and TM did not appear to serve as useful markers for predicting ARDS in patients at risk.


Asunto(s)
Endotelio Vascular/patología , Lipoproteínas/sangre , Síndrome de Dificultad Respiratoria/etiología , Trombomodulina/sangre , Factor de von Willebrand/metabolismo , Adulto , Biomarcadores/sangre , Estudios de Casos y Controles , Humanos , Valor Predictivo de las Pruebas , Síndrome de Dificultad Respiratoria/sangre
18.
Thromb Res ; 101(3): 203-11, 2001 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-11228343

RESUMEN

Tissue factor pathway inhibitor (TFPI) is the primary physiologic inhibitor of tissue factor-induced clotting. The TFPI gene contains three GATA motifs in the region flanking its transcription initiation sites. GATA motifs present in promoters of other genes bind GATA-2 transcription factor and thereby regulate their transcriptional expression. Both TFPI and GATA-2 transcription factor are synthesized by a variety of normal as well as malignant cells including hepatocellular carcinoma HepG2 and bladder carcinoma ECV304. Here, we studied whether the three GATA motifs flanking the transcription initiation sites regulate TFPI gene expression in HepG2 and ECV304 cells by binding to the GATA-2 transcription factor. Synthetic oligonucleotides containing GATA sequences from the TFPI regulatory region formed DNA-protein complexes with HepG2 and ECV304 nuclear extracts in an electrophoretic mobility shift assay. Using a 740-bp fragment (-496/+244) from TFPI regulatory region, the effect of base substitutions at each of the three GATA motifs was studied in a luciferase reporter gene system. TFPI promoter activity in HepG2 cells was increased 3-fold with mutation in one of the three GATA motifs and in ECV304 cells was essentially unchanged with mutations in all three GATA motifs. Thus, GATA motifs appear to serve a tissue-specific regulatory role in TFPI gene expression in malignant cells.


Asunto(s)
Lipoproteínas/genética , Neoplasias/genética , Proteínas de Unión al ADN/genética , Factor de Transcripción GATA2 , Regulación Neoplásica de la Expresión Génica , Humanos , Lipoproteínas/biosíntesis , Factores de Transcripción/genética , Células Tumorales Cultivadas , Dedos de Zinc
19.
J Infect ; 44(4): 236-9, 2002 May.
Artículo en Inglés | MEDLINE | ID: mdl-12099730

RESUMEN

Fungal infections of the skin and deeper tissues of the periorbital region are quite rare. We report a case of a localized, deep periorbital necrotizing Fusarium infection in an otherwise healthy, elderly lady. Since the clinical features and histopathological findings of Fusarium infection are by no means characteristic, the definitive diagnosis was achieved with the help of microbiological examination of cultured organisms. A combined medical and surgical therapy led to adequate control of infection. To conclude, localized, deep periorbital necrotizing soft tissue infection by Fusarium in an immunocompetent lady is not reported in literature. One should have a high index of suspicion for emerging fungal pathogens in the differential diagnosis of necrotizing orbital or adnexal conditions, even in an immunocompetent patient. The histologic findings of septate, branching hyphae and vascular invasion cannot distinguish Fusarium species from various other moulds such as Aspergillus species; microbiologic studies are essential for confirming the diagnosis.


Asunto(s)
Enfermedades Transmisibles Emergentes/microbiología , Infecciones Fúngicas del Ojo/microbiología , Fusarium/aislamiento & purificación , Inmunocompetencia , Anfotericina B/uso terapéutico , Antibacterianos/uso terapéutico , Antifúngicos/uso terapéutico , Catarata/terapia , Clotrimazol/uso terapéutico , Enfermedades Transmisibles Emergentes/tratamiento farmacológico , Infecciones Fúngicas del Ojo/tratamiento farmacológico , Femenino , Humanos , Implantación de Lentes Intraoculares/efectos adversos , Persona de Mediana Edad
20.
Inflammation ; 16(3): 241-50, 1992 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-1323530

RESUMEN

Recombinant human tumor necrosis factor-alpha (rTNF) stimulated increased generation of superoxide anion (O2-) by human neutrophils in a concentration-dependent fashion. Preincubation of human neutrophils with rTNF (2.2-2200 units/ml) for 10 min enhanced the subsequent generation of O2- in response to C5a and f-Met-Leu-Phe (FMLP). Recombinant TNF did not enhance O2- generation by neutrophils stimulated with phorbol myristate acetate (PMA). Recombinant TNF alone failed to induce release of myeloperoxidase (MPO) and lysozyme by neutrophils. However, it did enhance the release of MPO and lysozyme by neutrophils stimulated with C5a and FMLP, but not with PMA. Although rTNF alone (0.001-50,000 units/ml) was not chemotactic for neutrophils, preincubation of neutrophils with rTNF (0.001-0.1 units/ml) enhanced the chemotactic activity of suboptimal concentrations of C5a (0.1 nM) and FMLP (5 nM). Neutrophils treated with high concentrations of rTNF (100-10,000 units/ml) showed inhibition of random movement and of chemotaxis induced by C5a or FMLP. We conclude from these studies that rTNF primes neutrophils for enhanced responses to subsequent stimuli and thus may augment the inflammatory response by increased oxidant production and lysosomal enzyme release and promote down-regulation of chemotactic movement.


Asunto(s)
Quimiotaxis de Leucocito/efectos de los fármacos , Gránulos Citoplasmáticos/metabolismo , Neutrófilos/efectos de los fármacos , Estallido Respiratorio/efectos de los fármacos , Superóxidos/metabolismo , Factor de Necrosis Tumoral alfa/farmacología , Complemento C5a/farmacología , Gránulos Citoplasmáticos/enzimología , Sinergismo Farmacológico , Humanos , Muramidasa/metabolismo , N-Formilmetionina Leucil-Fenilalanina/farmacología , Oxígeno/metabolismo , Peroxidasa/metabolismo , Proteínas Recombinantes/farmacología
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