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1.
Int J Gynaecol Obstet ; 165(1): 169-175, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38071725

RESUMEN

OBJECTIVE: The aim of the study was to explore the utility of fluorescein sodium (FNa) as a contrast agent for colposcopy to detect premalignant and malignant lesions of cervix. The primary objective was to determine and compare the percentage detection of premalignant and malignant lesions of FNa and acetic acid (AA) positive areas. METHODS: This study included 120 screen positive women who underwent colposcopy using both 3% AA and FNa (0.06%). Observations for FNa staining were made under blue filter and directed biopsies were taken from acetowhite and fluorescent green areas. Benign lesions were considered as disease-negative and low grade squamous intraepithelial lesions (LSIL), high grade SIL (HSIL), and invasive cancer were considered as disease-positive. Correlation between histopathology and FNa and AA was determined by Kappa statistics. RESULTS: The mean age was 39.59 ± 10.73 years and median parity was 2. Out of 120 patients, 57 had benign lesions, 18 had LSIL, 33 had HSIL and 12 had invasive carcinomas. Sensitivity was 98.41% versus 64.91% respectively and specificity was 85.71% versus 35.09% respectively with FNa and AA. Diagnostic accuracy of FNa and AA was 82.50% versus 61.60%. There was good agreement between FNa staining and final histopathology and fair agreement between AA application and HPE (κ = 0.643 vs 0.213, P < 0.001). CONCLUSION: Using FNa as a contrast agent during colposcopy results in greater accuracy for detection of premalignant and malignant lesions of the cervix as compared to AA.


Asunto(s)
Lesiones Precancerosas , Lesiones Intraepiteliales Escamosas de Cuello Uterino , Displasia del Cuello del Útero , Neoplasias del Cuello Uterino , Embarazo , Humanos , Femenino , Adulto , Persona de Mediana Edad , Cuello del Útero/patología , Fluoresceína , Estudios Transversales , Medios de Contraste , Colposcopía/métodos , Lesiones Precancerosas/diagnóstico , Ácido Acético , Neoplasias del Cuello Uterino/diagnóstico , Neoplasias del Cuello Uterino/patología , Displasia del Cuello del Útero/patología , Lesiones Intraepiteliales Escamosas de Cuello Uterino/patología
2.
Nat Struct Mol Biol ; 30(6): 853-859, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-37081319

RESUMEN

In the early stages of mitosis, cohesin is released from chromosome arms but not from centromeres. The protection of centromeric cohesin by SGO1 maintains the sister chromatid cohesion that resists the pulling forces of microtubules until all chromosomes are attached in a bipolar manner to the mitotic spindle. Here we present the X-ray crystal structure of a segment of human SGO1 bound to a conserved surface of the cohesin complex. SGO1 binds to a composite interface formed by the SA2 and SCC1RAD21 subunits of cohesin. SGO1 shares this binding interface with CTCF, indicating that these distinct chromosomal regulators control cohesin through a universal principle. This interaction is essential for the localization of SGO1 to centromeres and protects centromeric cohesin against WAPL-mediated cohesin release. SGO1-cohesin binding is maintained until the formation of microtubule-kinetochore attachments and is required for faithful chromosome segregation and the maintenance of a stable karyotype.


Asunto(s)
Proteínas de Ciclo Celular , Centrómero , Humanos , Células HeLa , Centrómero/metabolismo , Proteínas de Ciclo Celular/metabolismo , Cinetocoros , Mitosis , Segregación Cromosómica , Cromátides/metabolismo
3.
J Biol Chem ; 294(4): 1240-1249, 2019 01 25.
Artículo en Inglés | MEDLINE | ID: mdl-30523153

RESUMEN

Ubiquitin (Ub)-conjugating enzymes and Ub ligases control protein degradation and regulate many cellular processes in eukaryotes. Cellular inhibitor of apoptosis protein-1 (cIAP1) plays a central role in apoptosis and tumor necrosis factor signaling. It harbors a C-terminal RING domain that homodimerizes to recruit E2∼Ub (where ∼ denotes a thioester bond) complex to catalyze Ub transfer. Noncovalent Ub binding to the backside of the E2 Ub-conjugating enzyme UbcH5 has previously been shown to enhance RING domain activity, but the molecular basis for this enhancement is unclear. To investigate how dimeric cIAP1 RING activates E2∼Ub for Ub transfer and what role noncovalently bound Ub has in Ub transfer, here we determined the crystal structure of the cIAP1 RING dimer bound to both UbcH5B covalently linked to Ub (UbcH5B-Ub) and a noncovalent Ub to 1.7 Å resolution. The structure along with biochemical analyses revealed that the cIAP1 RING domain interacts with UbcH5B-Ub and thereby promotes the formation of a closed UbcH5B-Ub conformation that primes the thioester bond for Ub transfer. We observed that the noncovalent Ub binds to the backside of UbcH5B and abuts UbcH5B's α1ß1-loop, which, in turn, stabilizes the closed UbcH5B-Ub conformation. Our results disclose the mechanism by which cIAP1 RING dimer activates UbcH5B∼Ub and indicate that noncovalent Ub binding further stabilizes the cIAP1-UbcH5B∼Ub complex in the active conformation to stimulate Ub transfer.


Asunto(s)
Proteínas Inhibidoras de la Apoptosis/química , Proteínas Inhibidoras de la Apoptosis/metabolismo , Enzimas Ubiquitina-Conjugadoras/química , Enzimas Ubiquitina-Conjugadoras/metabolismo , Ubiquitina/química , Ubiquitina/metabolismo , Cristalografía por Rayos X , Humanos , Modelos Moleculares , Unión Proteica , Conformación Proteica , Ubiquitinación
4.
Fertil Steril ; 105(4): 1102-10, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26776909

RESUMEN

OBJECTIVE: To characterize the efficacy of mifepristone treatment on extracellular matrix (ECM) production in leiomyomas. DESIGN: Laboratory study. SETTING: University research laboratory. PATIENT(S): None. INTERVENTION(S): Treatment of human immortalized two-dimensional (2D) and three-dimensional (3D) leiomyoma and myometrial cells with mifepristone and the progestin promegestone (R5020). MAIN OUTCOME MEASURE(S): Expression of COL1A1, fibronectin, versican variant V0, and dermatopontin in treated leiomyoma cells by Western blot analysis and confirmatory immunohistochemistry staining of treated 3D cultures. RESULT(S): Treatment with progestin stimulated production of COL1A1, fibronectin, versican, and dermatopontin. Mifepristone treatment inhibited protein production of these genes, most notably with versican expression. Combination treatment with both the agonist and antagonist further inhibited protein expression of these genes. Immunohistochemistry performed on 3D cultures demonstrated generalized inhibition of ECM protein concentration. CONCLUSION(S): Our study demonstrated that the progesterone agonist R5020 directly stimulated extracellular matrix components COL1A1, fibronectin, versican, and dermatopontin production in human leiomyoma cells. Progesterone antagonist mifepristone decreased protein production of these genes to levels comparable with untreated leiomyoma cells.


Asunto(s)
Matriz Extracelular/efectos de los fármacos , Matriz Extracelular/metabolismo , Antagonistas de Hormonas/farmacología , Leiomioma/metabolismo , Mifepristona/farmacología , Neoplasias Uterinas/metabolismo , Línea Celular Transformada , Relación Dosis-Respuesta a Droga , Matriz Extracelular/genética , Femenino , Humanos , Leiomioma/genética , Leiomioma/patología , Promegestona/farmacología , Células Tumorales Cultivadas , Neoplasias Uterinas/genética , Neoplasias Uterinas/patología
5.
Hemoglobin ; 40(6): 422-424, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-28361588

RESUMEN

In this short report, we describe the clinical presentation of a rare hemoglobin (Hb) variant, Hb Limassol [ß8(A5)Lys→Asn; HBB: c.27G>C] with a faster electrophoretic mobility than Hb A and that elutes in the P3 window on cation exchange high performance liquid chromatography (HPLC). This sequence variation at codon 8 (AAG>AAC) of the HBB gene was found in the four heterozygous cases, all of whom were clinically asymptomatic.


Asunto(s)
Variación Genética , Hemoglobinas Anormales/genética , Globinas beta/genética , Sustitución de Aminoácidos , Cromatografía Líquida de Alta Presión , Codón , Electroforesis , Femenino , Heterocigoto , Humanos , India , Masculino , Linaje
6.
Fertil Steril ; 105(1): 214-24, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26409322

RESUMEN

OBJECTIVE: To determine the effect of GnRH analogues (GnRH-a) leuprolide acetate (LA) and cetrorelix acetate on gonadal hormone-regulated expression of extracellular matrix in uterine leiomyoma three-dimensional (3D) cultures. DESIGN: Laboratory study. SETTING: University research laboratory. PATIENT(S): Women undergoing hysterectomy for symptomatic leiomyomas. INTERVENTION(S): The 3D cell cultures, protein analysis, Western blot, immunohistochemistry. MAIN OUTCOME MEASURE(S): Expression of extracellular matrix proteins, collagen 1, fibronectin, and versican in leiomyoma cells 3D cultures exposed to E2, P, LA, cetrorelix acetate, and combinations for 24- and 72-hour time points. RESULT(S): The 3D leiomyoma cultures exposed to E2 for 24 hours demonstrated an increased expression of collagen-1 and fibronectin, which was maintained for up to 72 hours, a time point at which versican was up-regulated significantly. Although P up-regulated collagen-1 protein (1.29 ± 0.04) within 24 hours of exposure, significant increase in all extracellular matrix (ECM) proteins was observed when the gonadal hormones were used concomitantly. Significant decrease in the amount of ECM proteins was observed on use of GnRH-a, LA and cetrorelix, with 24-hour exposure. Both the compounds also significantly decreased ECM protein concentration despite the presence of E2 or both gonadal hormones. CONCLUSION(S): This study demonstrates that GnRH-a directly affect the gonadal hormone-regulated collagen-1, fibronectin, and versican production in their presence. These findings suggest that localized therapy with GnRH-a may inhibit leiomyoma growth even in the presence of endogenous gonadal hormone exposure, thereby providing a mechanism to eliminate the hypoestrogenic side effects associated with GnRH-a therapy.


Asunto(s)
Antineoplásicos Hormonales/farmacología , Estradiol/farmacología , Matriz Extracelular/efectos de los fármacos , Hormona Liberadora de Gonadotropina/análogos & derivados , Leiomioma/tratamiento farmacológico , Leuprolida/farmacología , Acetato de Medroxiprogesterona/farmacología , Neoplasias Uterinas/tratamiento farmacológico , Técnicas de Cultivo de Célula , Línea Celular Tumoral , Colágeno Tipo I/metabolismo , Matriz Extracelular/metabolismo , Femenino , Fibronectinas/metabolismo , Hormona Liberadora de Gonadotropina/farmacología , Humanos , Leiomioma/metabolismo , Leiomioma/patología , Factores de Tiempo , Neoplasias Uterinas/metabolismo , Neoplasias Uterinas/patología , Versicanos/metabolismo
7.
Mol Cell ; 58(2): 297-310, 2015 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-25801170

RESUMEN

RING ubiquitin ligases (E3) recruit ubiquitin-conjugate enzymes (E2) charged with ubiquitin (Ub) to catalyze ubiquitination. Non-covalent Ub binding to the backside of certain E2s promotes processive polyUb formation, but the mechanism remains elusive. Here, we show that backside bound Ub (Ub(B)) enhances both RING-independent and RING-dependent UbcH5B-catalyzed donor Ub (Ub(D)) transfer, but with a more prominent effect in RING-dependent transfer. Ub(B) enhances RING E3s' affinities for UbcH5B-Ub, and RING E3-UbcH5B-Ub complex improves Ub(B)'s affinity for UbcH5B. A comparison of the crystal structures of a RING E3, RNF38, bound to UbcH5B-Ub in the absence and presence of Ub(B), together with molecular dynamics simulation and biochemical analyses, suggests Ub(B) restricts the flexibility of UbcH5B's α1 and α1ß1 loop. Ub(B) supports E3 function by stabilizing the RING E3-UbcH5B-Ub complex, thereby improving the catalytic efficiency of Ub transfer. Thus, Ub(B) serves as an allosteric activator of RING E3-mediated Ub transfer.


Asunto(s)
Enzimas Ubiquitina-Conjugadoras/química , Ubiquitina-Proteína Ligasas/química , Ubiquitina/metabolismo , Cristalografía por Rayos X , Modelos Moleculares , Simulación de Dinámica Molecular , Datos de Secuencia Molecular , Enzimas Ubiquitina-Conjugadoras/metabolismo , Ubiquitina-Proteína Ligasas/metabolismo , Dedos de Zinc
8.
Fertil Steril ; 102(3): 649-55, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-25106764

RESUMEN

Leiomyomas are benign soft-tissue neoplasms that arise from smooth muscle. Relief of symptoms (abnormal uterine bleeding, pain, pressure) is the major goal in management of women with significant symptoms. For symptomatic myomas, hysterectomy is a definitive solution; however, there are emerging less-invasive options. Magnetic resonance imaging-guided focused ultrasound surgery, cryomyolysis, and temporary occlusion of the uterine arteries are treatment options that are minimally invasive interventions with the benefit of preserving the uterus. This review summarizes procedure techniques, eligibility, complications, and outcomes of these alternate therapies.


Asunto(s)
Terapias Complementarias , Leiomioma/cirugía , Neoplasias Uterinas/cirugía , Útero/cirugía , Crioterapia/métodos , Femenino , Humanos , Terapia por Láser/métodos , Imagen por Resonancia Magnética Intervencional , Ultrasonografía Intervencional/métodos , Embolización de la Arteria Uterina
9.
J Neurol Surg A Cent Eur Neurosurg ; 75(4): 299-304, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24554610

RESUMEN

BACKGROUND AND STUDY AIMS: Perimesencephalic subarachnoid hemorrhage (PMSAH) was previously defined as a variant of subarachnoid hemorrhage (SAH) associated with a relatively benign clinical presentation and better outcomes than aneurysmal SAH. However, several prior studies have shown complications associated with PMSAH including vasospasm and hydrocephalus, and the need for follow-up imaging. We therefore reviewed our experience to further characterize the clinical consequences of PMSAH. MATERIALS AND METHODS: Eighty-eight consecutive patients who sustained spontaneous intracranial SAH and whose cerebral angiograms did not show any obvious source for SAH were retrospectively studied to characterize their prognosis and outcome based on SAH pattern. Glasgow Coma Scale and Hunt-Hess scores on admission, the incidence of vasospasm or hydrocephalus, the need for an external ventricular drain, and shunt dependence, along with Glasgow outcome score (GOS) at discharge and follow-up, were used to draw comparisons between perimesencephalic and diffuse SAH patient populations. RESULTS: Patients with perimesencephalic SAH differed statistically (p < 0.05) from patients with diffuse SAH in regard to age, Hunt-Hess score on presentation, hospital length of stay, GOS at discharge, and incidence of hydrocephalus, angiographic vasospasm, and clinical vasospasm. CONCLUSION: Our data demonstrate that although the patients with perimesencephalic SAH fared better than those with diffuse SAH, their outcomes were worse than those of similar patients with PMSAH who have been previously reported in the literature.


Asunto(s)
Hidrocefalia/etiología , Hemorragia Subaracnoidea/complicaciones , Vasoespasmo Intracraneal/etiología , Adulto , Factores de Edad , Anciano , Angiografía Cerebral , Femenino , Humanos , Hidrocefalia/diagnóstico por imagen , Masculino , Persona de Mediana Edad , Pronóstico , Estudios Retrospectivos , Hemorragia Subaracnoidea/diagnóstico por imagen , Hemorragia Subaracnoidea/cirugía , Vasoespasmo Intracraneal/diagnóstico por imagen
10.
Acta Cytol ; 56(3): 277-84, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22555530

RESUMEN

OBJECTIVE: The present study was undertaken to assess the therapeutic effects of topical ozonated oil on early healing of free gingival graft surgical sites. STUDY DESIGN: Twenty subjects were entered into this triple-blinded, randomized, placebo-controlled clinical trial, designed to evaluate the efficacy of ozonated oil on free gingival graft surgical wounds. Subjects were assigned to either the ozone group, in which ozonated oil was applied to the surgical wound, or the control group, in which non-ozonated oil was used as a control. Patients were postoperatively evaluated by cytological analysis. Cytological analysis consisted of the keratinisation and superficial cell indices measured at baseline, after 24 h, on the 3rd, 7th, 14th and 21st day and 2, 3, 8 and 18 months postoperatively. RESULTS: Cytological results showed that there was a significant (p < 0.001) improvement in epithelial healing by the 7th, 14th and 21st day and 2, 3 and 8 months postoperatively in the ozone group compared to the control group. CONCLUSION: The present study showed significant improvement in epithelial healing and gingival health after topical application of ozone-treated plant oil to gingival surgical sites.


Asunto(s)
Encía/efectos de los fármacos , Enfermedades de las Encías/patología , Ozono/administración & dosificación , Hueso Paladar/efectos de los fármacos , Aceites de Plantas/administración & dosificación , Complicaciones Posoperatorias/tratamiento farmacológico , Complicaciones Posoperatorias/patología , Cicatrización de Heridas/efectos de los fármacos , Adulto , Método Doble Ciego , Femenino , Encía/patología , Encía/cirugía , Enfermedades de las Encías/tratamiento farmacológico , Enfermedades de las Encías/cirugía , Humanos , Masculino , Aceite de Oliva , Ozono/química , Hueso Paladar/patología , Hueso Paladar/cirugía , Complicaciones Posoperatorias/fisiopatología , Factores de Tiempo , Sitio Donante de Trasplante/patología , Sitio Donante de Trasplante/fisiopatología , Resultado del Tratamiento , Cicatrización de Heridas/fisiología , Adulto Joven
11.
J Investig Clin Dent ; 2(4): 248-58, 2011 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25426896

RESUMEN

AIM: To evaluate the effect of ozonated oil on palatal wounds. METHODS: Eighteen patients were randomized and allocated to either the ozone group (n = 8) or control (n = 10) group. Free gingival graft surgery was performed, and post-harvested palatal wounds were treated with either 2 mL ozonated oil or control oil daily for 1 week. A planimetrical analysis analyzed the digital image for the wound sizes and shape factor at baseline, at 24 h, and days 5, 7, 14, 21, and 28, postoperatively. A cytological analysis used the keratinization and superficial cell indices at baseline, 24 h, and days 3, 7, 14, and 21 and the second and third months, postoperatively. RESULTS: Planimetrical results showed a significant (P ≤ 0.05) improvement in wound size on days 5, 7, 14, 21, and 28, postoperatively, in the ozone group compared to the control group. Cytological results showed a significant (P ≤ 0.001) improvement in epithelial healing on days 7, 14, and 21, and the second and third months, postoperatively, after the application of ozonated oil compared to control oil. CONCLUSION: Our results showed significant improvement in wound size and epithelial healing after topical ozonated oil application compared to control oil on palatal wounds.


Asunto(s)
Encía/trasplante , Ozono/uso terapéutico , Aceites de Plantas/uso terapéutico , Administración Tópica , Adulto , Citodiagnóstico/métodos , Índice de Placa Dental , Femenino , Estudios de Seguimiento , Encía/efectos de los fármacos , Recesión Gingival/cirugía , Gingivectomía/métodos , Humanos , Queratinas/análisis , Estudios Longitudinales , Masculino , Aceite de Oliva , Ozono/administración & dosificación , Placebos , Aceites de Plantas/administración & dosificación , Repitelización/efectos de los fármacos , Regeneración/efectos de los fármacos , Sitio Donante de Trasplante/patología , Cicatrización de Heridas/efectos de los fármacos , Adulto Joven
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