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1.
Am Surg ; 67(7): 630-2, 2001 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-11450775

RESUMEN

Cholelithiasis is a common problem in the United States, affecting 10 to 15 per cent of the population. Although only one per cent of these patients have intrahepatic gallstones their discovery intraoperatively may present a technical challenge for the surgeon. This paper describes a simple method for dislodging difficult intrahepatic biliary stones: modification of a rigid choledochoscope to permit use of a biliary Fogarty catheter and Segura basket under direct visualization.


Asunto(s)
Conductos Biliares Intrahepáticos , Colelitiasis/cirugía , Endoscopios , Endoscopía del Sistema Digestivo , Adulto , Enfermedades de los Conductos Biliares/diagnóstico por imagen , Enfermedades de los Conductos Biliares/cirugía , Cateterismo , Colangiopancreatografia Retrógrada Endoscópica , Colelitiasis/diagnóstico por imagen , Femenino , Humanos , Radiografía Intervencional
2.
Ann Plast Surg ; 42(5): 553-63, 1999 May.
Artículo en Inglés | MEDLINE | ID: mdl-10340867

RESUMEN

Thrombospondin 1 (TSP-1), an adhesive glycoprotein, plays an important role in platelet adhesion, inflammation, cell-cell interaction, and angiogenesis. TSP-1 is expressed by endothelial cells, fibroblasts, and macrophages. The unique cysteine-serinevaline-threonine-cysteine-glycine (CSVTCG) binding domain of TSP-1 also plays an important role in cell binding and modulation of cellular processes. The purpose of this study was to evaluate histologically and quantitatively TSP-1 and its CSVTCG receptor in fetal skin wounds over time. Pregnant ewes underwent laparotomy and hysterotomy. At 65 days gestation (term, 145 days), incisional and excisional wounds were created on the fetal back in a similar position on each animal. The uterus and laparotomy were closed. The wounds were harvested on days 1, 3, 7, 21, and 28. Expression of TSP-1 and its CSVTCG receptor was evaluated immunohistochemically and quantitated by computer image analysis in units of absorbance. Immunoglobulin G (negative) controls were performed and subtracted from the TSP-1 sample to eliminate background absorbance readings. Serum (negative) control was used for the CSVTCG receptor. Platelet concentrates were used as the positive control: TSP-1, 63.43; CSVTCG, 58.72. Results are expressed as absorbance+/-SEM. Results of TSP-1 are as follows: day 1, 33.02+/-0.26; day 3, 22.21+/-0.14; day 7, 20.56+/-1.07; day 21, 7.76+/-0.40; and day 28, 5.99+/-0.03. TSP-1 displays an early peak during fetal skin repair, followed by a steep decrease over the viewed time period. Results of CSVTCG receptor are as follows: day 1, 26.19+/-2.43; day 3, 30.20+/-0.64; day 7, 24.56+/-0.80; day 21, 24.70+/-0.40; and day 28, 21.65+/-1.39. Thus, CSVTCG receptor displays a slowed decrease in expression over time during fetal repair. No significant differences were noted between incisional and excisional samples. Temporal and histological differences exist in the localization and expression of TSP-1 and its CSVTCG receptor during fetal wound repair. TSP-1 is upregulated in tissues early. This corresponds with the known role of TSP-1 in cell-cell interaction, including potentiation of growth factor activity. TSP-1 also modulates matrix, allowing scar-free provisional matrix in the earlier stages of repair deposited by platelets. The potentiation of cell-associated protease activity by TSP-1 can support tissue and matrix turnover. This activity of TSP-1 may contribute to the formation of a scarless wound. TSP-1 destabilizes extracellular matrix contacts, and facilitates mitosis and migration. The action of TSP-1 as an adhesive protein allows numerous different cells to adhere to the extracellular membrane. CSVTCG receptor expression decreases during fetal repair as the cells migrate to the epithelial surface, suggesting a significant role of the CSVTCG receptor in keratinocytic maturation, differentiation, and epithelization.


Asunto(s)
Adhesión Celular/fisiología , Feto/fisiología , Piel/metabolismo , Trombospondina 1/metabolismo , Cicatrización de Heridas/fisiología , Animales , Matriz Extracelular/fisiología , Femenino , Inmunohistoquímica , Embarazo , Receptores de Aminoácidos , Ovinos
3.
J Burn Care Rehabil ; 19(6): 487-93, 1998.
Artículo en Inglés | MEDLINE | ID: mdl-9848038

RESUMEN

Thrombospondin-1 (TSP-1), an adhesive glycoprotein, plays an important role in platelet adhesion, inflammation, cell-to-cell interaction, and angiogenesis. TSP-1 is expressed by endothelial cells, fibroblasts, and macrophages. TSP-1's unique cysteine-serine-valine-threonine-cysteine-glycine (CSVTCG) specific receptor plays an important role in the binding and modulation of cellular adhesion and invasion. This article histologically and quantitatively evaluates TSP-1 and its CSVTCG receptor in adult burn wounds over time. Tissue was obtained from burn wounds on several days and samples that were 5 microns thick were placed on slides. Expression of TSP-1 and its CSVTCG receptor were evaluated immunohistochemically and quantitated by computer image analysis in units of absorbance. Immunoglobin G (IgG) (negative) controls were performed and subtracted from the TSP-1 sample to eliminate background absorbance readings. Serum (negative) control was used for the CSVTCG receptor. Platelet concentrates were used as the positive control. A quantitative examination of the results yielded the following information, expressed as absorbance +/- standard error of the mean: TSP-1: day 1, 62.0 +/- 10.13; day 3, 76.2 +/- 6.90; day 5, 36.0 +/- 3.96; day 7, 60.4 +/- 5.67; and day 9, 29.5 +/- 2.91. TSP-1 displays an early peak, followed by a steep decrease over the time period studied. The readings for the CSVTCG receptor are as follows: day 1, 33.8 +/- 1.87; day 3, 34.5 +/- 5.39; day 7, 39.1 +/- 1.93; day 21, 39.1 +/- 1.93; day 28, 34.8 +/- 3.67. In contrast, the CVSTCG receptor continues to be present in the wound over time. Histologic findings are reported, and photographs and a histopathologic analysis are included. The information presented in this article leads to the conclusion that temporal and histologic differences exist in the localization and expression of TSP-1 and its CSVTCG receptor. TSP-1 is up-regulated in injured tissues immediately after the injury; it is rapidly down-regulated as the tissue heals. In contrast, the levels of the CSVTCG receptor remain relatively constant during the healing process. These data are consistent with TSP-1's known role in cell-to-cell interaction, including the modulation of the growth factor and protease activity.


Asunto(s)
Quemaduras/patología , Receptores de Superficie Celular/análisis , Trombospondina 1/análisis , Adulto , Distinciones y Premios , Quemaduras/fisiopatología , División Celular/fisiología , Técnicas de Cultivo , Humanos , Interpretación de Imagen Asistida por Computador , Inmunohistoquímica , Puntaje de Gravedad del Traumatismo , Países Bajos , Receptores de Superficie Celular/metabolismo , Valores de Referencia , Piel/patología , Trombospondina 1/metabolismo , Cicatrización de Heridas/fisiología
4.
Histol Histopathol ; 13(4): 967-71, 1998 10.
Artículo en Inglés | MEDLINE | ID: mdl-9810490

RESUMEN

Thrombospondin-1 (TSP-1) is a matrix protein implicated in mechanisms of wound healing. TSP-1 contains the sequence cysteine-serine-valine-threonine-cysteine-glycine (CSVTCG) that has been shown to function primarily as a cell adhesion domain. Our laboratory has isolated a novel receptor specific for the CSVTCG adhesive domain of TSP-1. Immunohistochemical staining techniques and computerized image analysis were used to identify and quantitate TSP-1 and its CSVTCG receptor in surgically created colon anastomotic wounds. Histopathologic and quantitative examination demonstrated increased expression of TSP-1 and its CSVTCG receptor in areas of wound healing. These findings suggest a role for TSP-1 and its CSVTCG receptor in wound healing. The control of expression and activity of these molecules may eventually be the basis for the development of wound healing agents that could significantly reduce the morbidity from surgical intervention.


Asunto(s)
Colon/química , Receptores de Superficie Celular/análisis , Trombospondina 1/análisis , Cicatrización de Heridas , Anastomosis Quirúrgica , Animales , Moléculas de Adhesión Celular/metabolismo , Colon/metabolismo , Colon/patología , Humanos , Masculino , Fragmentos de Péptidos/metabolismo , Conejos , Ratas , Ratas Sprague-Dawley
5.
Ann Plast Surg ; 40(5): 494-501, 1998 May.
Artículo en Inglés | MEDLINE | ID: mdl-9600434

RESUMEN

Growth factors play a crucial role in the regulation of cellular proliferation and matrix degradation in wound healing and cancer. We have shown that thrombospondin 1 (TSP-1) and its cysteine-serine-valine-threonine-cysteine-glycine (CSVTCG)-specific receptor play a key role in cell invasion and matrix degradation in different carcinomas. The present study was done to determine whether TSP-1 and its receptor show a similar pattern of expression in wound healing and cancer. Expression and localization of TSP-1 and its receptor were determined in fetal wounds, adult burn wounds, and different human malignancies by immunohistochemical staining and computerized image analysis. In healing wounds, TSP-1 was expressed in the stroma early in the process, followed by a steep decline. The TSP-1 receptor localized to neovessels and highly proliferating cells (i.e., fibroblasts, basal cells), its levels remaining relatively constant. Cancer cells and tumor-associated microvessels expressed the TSP-1 receptor, whereas TSP-1 localized predominantly to the tumor-associated stroma. These data suggest a critical role for TSP-1 and its CSVTCG-specific receptor in wound healing and cancer.


Asunto(s)
Neoplasias de la Mama/metabolismo , Receptores de Superficie Celular/metabolismo , Trombospondina 1/metabolismo , Cicatrización de Heridas/fisiología , Adulto , Animales , Neoplasias de la Mama/patología , Epitelio/patología , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador , Inmunohistoquímica , Receptores de Superficie Celular/biosíntesis , Ovinos , Trombospondina 1/biosíntesis , Factores de Tiempo
6.
J Surg Res ; 74(1): 11-6, 1998 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-9536966

RESUMEN

BACKGROUND: Thrombospondin-1 (TSP-1) is important in platelet adhesion and aggregation, inflammation, cell to cell interaction, angiogenesis, and smooth muscle cell (SMC) proliferation. TSP-1 expression increases rapidly with injury. Therefore, we hypothesize that TSP-1 may play a role in the development of intimal hyperplasia (IH). The purpose of this study is to examine the interaction between cholesterol and TSP-1 on SMC proliferation and to quantitatively assess TSP-1 expression in an established model of IH, with and without underlying cholesterol-induced atherosclerosis. MATERIALS AND METHODS: In vitro, rabbit aortic SMC culture studies were performed to see the effect of TSP-1 antibodies on PDGF and, separately, cholesterol-induced SMC proliferation. In vivo, 23 rabbits were fed either a regular or a high-cholesterol diet. Hypercholesterolemia was confirmed by measurement of serum levels. Subsets underwent intraluminal aortic injury. Aortas were harvested 8-10 weeks later. Arterial wall TSP-1 was evaluated immunohistochemically and quantified by computer image analysis. RESULTS: In vitro, TSP-1 antibodies were able to inhibit PDGF and cholesterol-induced SMC proliferation (P < 0.05). In vivo, TSP-1 was found predominantly in the extracellular matrix in the rabbit aorta. IH was uniformly seen status-post angioplasty. Hyperplasia was more prominent in samples from hypercholesterolemic animals. ANOVA and Student's t test analyses demonstrated significantly more TSP-1 in the high-cholesterol/angioplasty group than in all other groups (P = 0.0006 vs regular diet/no angioplasty group). CONCLUSIONS: These data are consistent with the hypothesis that TSP-1 contributes to the development of IH. This study suggests that injured arteries in hypercholesterolemic atherosclerotic rabbits overexpress TSP-1.


Asunto(s)
Hipercolesterolemia/metabolismo , Músculo Liso Vascular/metabolismo , Músculo Liso Vascular/patología , Trombospondina 1/metabolismo , Animales , Arteriosclerosis/etiología , Arteriosclerosis/metabolismo , Arteriosclerosis/patología , División Celular/efectos de los fármacos , Células Cultivadas , Modelos Animales de Enfermedad , Hipercolesterolemia/complicaciones , Hiperplasia/etiología , Hiperplasia/metabolismo , Hiperplasia/patología , Masculino , Músculo Liso Vascular/efectos de los fármacos , Factor de Crecimiento Derivado de Plaquetas/farmacología , Conejos , Trombospondina 1/antagonistas & inhibidores
7.
Clin Plast Surg ; 24(4): 687-703, 1997 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-9342511

RESUMEN

The diagnosis and treatment of adnexal cancers continues to pose a challenge to a wide range of clinicians. The diseases are a diverse lot, owing to the wide range of skin structures and large surface area. Early recognition and treatment are key to improved outcomes. Education of the patients as to their role in their care, especially early detection, is also of crucial importance. Further study may yield information to improve diagnosis and treatment.


Asunto(s)
Carcinoma de Apéndice Cutáneo/patología , Carcinoma de Células Escamosas/patología , Neoplasias de las Glándulas Sebáceas/patología , Neoplasias Cutáneas/patología , Biopsia , Carcinoma de Apéndice Cutáneo/etiología , Carcinoma de Apéndice Cutáneo/terapia , Carcinoma de Células Escamosas/etiología , Carcinoma de Células Escamosas/terapia , Terapia Combinada , Diagnóstico Diferencial , Humanos , Incidencia , Neoplasias de las Glándulas Sebáceas/etiología , Neoplasias de las Glándulas Sebáceas/terapia , Neoplasias Cutáneas/etiología , Neoplasias Cutáneas/terapia
8.
Histol Histopathol ; 12(4): 1013-8, 1997 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-9302563

RESUMEN

Thrombospondin-1 (TSP-1) is a matrix protein implicated in mechanisms of tumor metastasis. TSP-1 has a characteristic Cysteine-Serine-Valine-Threonine-Cysteine-Glycine (CSVTCG) sequence that functions as a tumor cell adhesion domain. Our laboratory has isolated a novel CSVTCG specific tumor cell receptor. Immunohistochemical staining techniques and computerized image analysis were used to identify and quantitate the CSVTCG receptor of TSP-1 in a wide spectrum of human archival breast tumors. Histopathologic and quantitative examination was correlated with clinical findings two years post operation. Increasing amounts of CSVTCG receptor correlated positively with worsening histopathologic and clinical findings. These findings suggest a role for the TSP-1 CSVTCG receptor in breast tumor progression. This receptor may have utility for the diagnosis, staging, and treatment of this common and deadly disease.


Asunto(s)
Neoplasias de la Mama/metabolismo , Neoplasias de la Mama/patología , Trombospondina 1/metabolismo , Carcinoma/patología , Progresión de la Enfermedad , Epitelio/patología , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador , Inmunohistoquímica
9.
Gen Comp Endocrinol ; 85(3): 486-92, 1992 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-1577249

RESUMEN

The lizard Anolis carolinensis exhibits asymmetric ovarian growth. At any given time, the larger ovary (LO) contains a larger follicle than does the smaller ovary (SO). Physiologically hypophysectomized females with quiescent ovaries were treated with gonadotropin (ovine FSH) or saline vehicle after either surgical removal of the LO or sham operation. The smaller ovaries of initial control, sham-operated, and hemiovariectomized (HO) females were similar in weight and follicular size. Therefore, endogenous gonadotropin secretion remained at subthreshold levels during the experiment and after HO. FSH significantly stimulated ovarian follicular growth in both sham-operated and HO females. However, the response of the SO of HO females to FSH was significantly greater than that in sham-operated females. These results demonstrate a greater sensitivity of the SO to FSH if the LO is absent.


Asunto(s)
Hormona Folículo Estimulante/farmacología , Lagartos/fisiología , Ovario/efectos de los fármacos , Animales , Peso Corporal/efectos de los fármacos , Femenino , Inyecciones Subcutáneas , Tamaño de los Órganos/efectos de los fármacos , Ovario/anatomía & histología
15.
J Periodontol ; 51(12): 686-90, 1980 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-6937640

RESUMEN

Thirty-four areas of gingival recession in ten patients were treated by a coronally repositioned flap procedure. All but four of these areas had received a free gingiva graft previously. The postoperative evaluations of the wound healing were made at 2 weeks and at 1, 2, 4, 6 and 12 months after the final surgery. In most cases the amount of gingival recession was reduced with the average tissue gain being 1.82 mm. The gingival sulcus depth was unaffected by the procedure. Several cases showed total root coverage. Although the procedure described has many advantages, the authors feel these must be carefully weighed against the disadvantages before subjecting patients to such surgery.


Asunto(s)
Enfermedades de las Encías/cirugía , Colgajos Quirúrgicos , Adulto , Encía/patología , Enfermedades de las Encías/patología , Bolsa Gingival/patología , Gingivoplastia , Humanos , Persona de Mediana Edad , Raíz del Diente , Cicatrización de Heridas
16.
Science ; 210(4469): 548-50, 1980 Oct 31.
Artículo en Inglés | MEDLINE | ID: mdl-7423204

RESUMEN

All living and most fossil representatives of the reptilian subclass Archosauria lack pineal bodies. Arrhythmic, low-level, nonpineal melatonin is present, however, in the blood of Alligator mississippiensis. Although pineal bodies have been implicated in circadian phenomena, these results suggest that arrhytmic melatonin in alligators may not be involved incircadian events and indicate that the pineal is not the only source of the hormone melatonin. The evolutionary loss of the pineal in Archosauria occurred during the Mesozoic, and era noted for its seasonal stability. Arrhythmic melatonin titers inalligators and pineal loss in alligators and other archosaurs may be related to Mesozoic seasonal stability.


Asunto(s)
Caimanes y Cocodrilos/sangre , Melatonina/sangre , Reptiles/sangre , Animales , Evolución Biológica , Periodicidad , Glándula Pineal/fisiología , Radioinmunoensayo
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