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1.
Int J Oral Maxillofac Surg ; 51(4): 493-500, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-34426056

RESUMEN

The amount of blood loss determined in orthognathic surgery differs greatly among studies. This can be attributed to the inhomogeneity in study cohorts analysed, but may also be a result of the varying methodologies used for blood loss determination. However, this has yet to be explored. Thus, the aim of this study was to investigate the extent to which the formula and time point used to measure blood loss affect the blood loss volume, determined in a homogeneous cohort undergoing bimaxillary surgery. Blood loss was calculated at 24 and 48 hours postoperatively using the haemoglobin balance method and the formula of Hurle et al. The estimated total blood volume was established based on the formulae of Nadler et al. and Choi et al. Differences in blood loss volume with respect to time point and formula were analysed and compared. Fifty-four patients were included in the final analysis. Statistically significant differences in blood loss were observed: a significant increase in the blood loss volume from 24 hours to 48 hours postoperatively was detected. When comparing the formulae used, blood loss differed significantly at 24 hours after surgery; however no such difference resulted at 48 hours postoperatively. These findings imply that the time point of measuring blood loss is highly relevant, whereas the formulae applied seem to have less of an impact on the blood loss volumes calculated.


Asunto(s)
Cirugía Ortognática , Procedimientos Quirúrgicos Ortognáticos , Pérdida de Sangre Quirúrgica , Humanos , Procedimientos Quirúrgicos Ortognáticos/métodos
2.
Hernia ; 25(4): 939-950, 2021 08.
Artículo en Inglés | MEDLINE | ID: mdl-34309770

RESUMEN

PURPOSE: The postpartum abdomen presents significant challenges to the surgeon. It is anatomically complex, with often substantial symptomatic divarication of the rectus abdominis, affecting all anterior abdominal wall layers. This may lead to profound functional sequelae, and often, of more importance to patients, a significant physical deformity. The complex interplay of functional/physical symptoms can result in reduced quality of life (QoL) as well as negative body image/self-esteem. Postpartum women may seek abdominoplasty to address the whole scope of these concerns. Whilst techniques have evolved achieving such goals operatively, the impact of such surgery on QoL/mental health has yet to be established. METHODS: We perform a comprehensive review of potential options of validated patient-reported outcome measures (PROMs) for consideration of use in postpartum women seeking abdominoplasty; in addition to discussing current driving factors for seeking surgery and associated ethics. RESULTS: Pressure on postpartum women to return their abdominal wall contour to a pre-pregnant state is high. This poses important ethical considerations for surgeons. There are several well-established/validated PROMs used in body contouring in massive weight loss/bariatric population groups, including Body-Q and Body-QoL scales, but none yet specific to postpartum women. CONCLUSION: PROMs use to enable establishment of the true value of abdominoplasty in postpartum women, not just in terms of functional/physical restoration, but also in terms of delivering a positive impact on patients' mental health and QoL, are important. Further research is needed to determine if those already developed are appropriate or whether a postpartum-specific PROM would be beneficial.


Asunto(s)
Pared Abdominal , Abdominoplastia , Pared Abdominal/cirugía , Femenino , Herniorrafia , Humanos , Periodo Posparto , Embarazo , Calidad de Vida , Recto del Abdomen/cirugía
3.
Int J Oral Maxillofac Surg ; 49(6): 726-733, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-31699632

RESUMEN

Patient dissatisfaction with labial appearance in the adult cleft lip is frequently linked to poor upper lip projection. Other areas of concern include asymmetry and impaired upper lip height. Different surgical techniques are available to address volumetric deficiencies, according to extent and localization. However, data comparing outcomes in these different areas are limited. The main aim of this study was to assess the relative gains in upper lip projection. An evaluation of upper vermilion height and symmetry was also performed. Thirty-seven consecutive patients treated by a single surgeon had their pre- and postoperative results measured using standardized photographs; these were analysed using subjective and objective outcome measures. Seven examiners evaluated anonymized pre- and postoperative side and front views for subjective evaluation. The objective analysis was performed using Adobe Photoshop. Fifteen lip revisions, four Abbe flaps, 12 dermal grafts, and six PermaLip implants were performed. In bilateral cleft lip and palate patients, Abbe flaps showed the most significant improvement in labial projection, followed by PermaLip implants and dermal grafts. In unilateral cleft lip and palate patients, PermaLip implants best addressed impaired lip projection, followed by dermal grafts. Overall, functional lip revisions showed excellent outcomes for upper lip symmetry; however, only minor changes in labial projection were found.


Asunto(s)
Labio Leporino/cirugía , Procedimientos de Cirugía Plástica , Adulto , Humanos , Mucosa Bucal , Reoperación , Trasplante de Piel , Colgajos Quirúrgicos
5.
EJVES Short Rep ; 35: 1-6, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28856331

RESUMEN

OBJECTIVE/BACKGROUND: Phaeochromocytomas and paragangliomas are vascular neuroendocrine tumours distributed between the neck and the pelvis and may be associated with catecholamine secretion. The aim of the study was to describe the complex surgical management required to excise these tumours when in close proximity to the great vessels (aorta and vena cava). METHODS: This was a retrospective case series. Patients included those undergoing surgical excision of a phaeochromocytoma or paraganglioma involving the great vessels. Data on clinical presentation; genetic mutations; tumour location; catecholamine/metanephrine secretion; surgical strategy; pre-, intra-, and post-operative course were collated. RESULTS: Five patients (age range 16-60 years) were identified; three had thoracic paragangliomas located under the arch of the aorta, one had an abdominal paraganglioma invading the aorta, and one had a massive phaeochromocytoma invading the inferior vena cava via the adrenal vein. Three patients had predisposing germline mutations. All patients had adrenergic blockade prior to surgery. A diverse range of complex surgical techniques were employed to excise tumours, including cardiopulmonary bypass, aortic resection, grafting and venotomy of the vena cava. Early post-operative complications were limited. CONCLUSIONS: Excision of phaeochromocytomas and paragangliomas involving the great vessels is high risk surgery optimally undertaken within a multidisciplinary setting in a tertiary referral centre. Comprehensive radiological and biochemical assessment, meticulous pre-operative preparation and close intra- and post-operative monitoring are essential. Radiological imaging may be unable to resolve the tumour extent and anatomy pre-operatively and direct visualisation of the tumour may be the only way to clarify the surgical strategy. Pre-operative knowledge of the genetic predisposition may influence surgical management.

6.
Br J Oral Maxillofac Surg ; 55(3): 242-245, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-28216308

RESUMEN

Craniofacial endosseous implants are regularly used to support prostheses in the rehabilitation of complex defects, but reported success rates vary. To review our own clinical practice over 10 years, and particularly to examine the impact of radiotherapy and the timing of placement on the survival of implants, we retrospectively audited the records for all patients who had endosseous implants for prosthetic rehabilitation in our unit between 2005 and 2015. We reviewed 167 records, which gave 451 implants, of which, 222 (49%) were auricular, 98 (22%) nasal, and 131 (29%) orbital. Most were placed after ablative operations for cutaneous malignancy (n=103 patients, 62%). The failure rate of implants placed in bone that was irradiated either before or after placement was significantly higher than that of those placed in non-irradiated bone (univariate analysis: 11% compared with 2%, p<0.001: Kaplan-Meier survival analysis: p<0.001). The timing of placement in relation to radiotherapy (before compared with after) seemed to have no impact on success (p=0.96). Our findings are in keeping with previous reports, and the principal observation is that radiotherapy adversely affects success. We work closely with our maxillofacial prosthetists and place implants at the time of ablation. Our findings seem to support this practice regardless of whether or not the patient will later require adjuvant radiotherapy.


Asunto(s)
Implantación de Prótesis Maxilofacial , Prótesis Maxilofacial , Huesos Faciales/cirugía , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Cráneo/cirugía , Factores de Tiempo
7.
J Pharmacol Exp Ther ; 360(2): 346-355, 2017 02.
Artículo en Inglés | MEDLINE | ID: mdl-27965369

RESUMEN

Although the physiologic role of muscarinic receptors in bladder function and the therapeutic efficacy of muscarinic antagonists for the treatment of overactive bladder are well established, the role of ß3-adrenergic receptors (ß3ARs) and their potential as therapeutics is just emerging. In this manuscript, we characterized the pharmacology of a novel ß3AR agonist vibegron (MK-4618, KRP-114V) and explored mechanistic interactions of ß3AR agonism and muscarinic antagonism in urinary bladder function. Vibegron is a potent, selective full ß3AR agonist across species, and it dose dependently increased bladder capacity, decreased micturition pressure, and increased bladder compliance in rhesus monkeys. The relaxation effect of vibegron was enhanced when combined with muscarinic antagonists, but differentially influenced by muscarinic receptor subtype selectivity. The effect was greater when vibegron was co-administered with tolterodine, a nonselective antagonist, compared with coadministration with darifenacin, a selective M3 antagonist. Furthermore, a synergistic effect for bladder strip relaxation was observed with the combination of a ß3AR agonist and tolterodine in contrast to simple additivity with darifenacin. To determine expression in rhesus bladder, we employed a novel ß3AR agonist probe, [3H]MRL-037, that selectively labels ß3 receptors in both urothelium and detrusor smooth muscle. Vibegron administration caused a dose-dependent increase in circulating glycerol and fatty acid levels in rhesus and rat in vivo, suggesting these circulating lipids can be surrogate biomarkers. The translation of our observation to the clinic has yet to be determined, but the combination of ß3AR agonists with M2/M3 antimuscarinics has the potential to redefine the standard of care for the pharmacological treatment of overactive bladder.


Asunto(s)
Agonistas de Receptores Adrenérgicos beta 3/farmacología , Antagonistas Muscarínicos/farmacología , Pirimidinonas/farmacología , Pirrolidinas/farmacología , Receptores Adrenérgicos beta 3/metabolismo , Vejiga Urinaria Hiperactiva/tratamiento farmacológico , Agonistas de Receptores Adrenérgicos beta 3/uso terapéutico , Animales , Interacciones Farmacológicas , Femenino , Humanos , Macaca mulatta , Masculino , Antagonistas Muscarínicos/uso terapéutico , Músculo Liso/efectos de los fármacos , Músculo Liso/fisiopatología , Transporte de Proteínas/efectos de los fármacos , Pirimidinonas/uso terapéutico , Pirrolidinas/uso terapéutico , Ratas , Especificidad de la Especie , Vejiga Urinaria/efectos de los fármacos , Vejiga Urinaria/fisiopatología , Vejiga Urinaria Hiperactiva/metabolismo , Vejiga Urinaria Hiperactiva/fisiopatología , Urodinámica/efectos de los fármacos
8.
Br J Oral Maxillofac Surg ; 53(10): 1035-7, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26148777

RESUMEN

The clinical use of rapid prototype, 3-dimensional models and pre-bent reconstruction plates is recognised for mandibular reconstruction after resection of cancer. We describe a new approach using similar techniques in the management of complicated mandibular fractures.


Asunto(s)
Fracturas Conminutas/cirugía , Fracturas Mandibulares/cirugía , Placas Óseas , Humanos , Mandíbula/cirugía , Reconstrucción Mandibular
9.
Br J Dermatol ; 152(2): 225-30, 2005 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-15727632

RESUMEN

BACKGROUND: The colocalization of insulin-like growth factor binding protein-3 (IGFBP-3) and IGF-I receptor (IGF-IR) in the basal/germinative layer of the epidermis suggests a key role in modulating epidermal homeostasis. OBJECTIVES: We aimed to clarify both the specific cellular localization and the effect of excess epidermal IGFBP-3 on keratinocyte proliferation. METHODS: (i) Total RNA was isolated from fluorescence-activated cell sorted basal human keratinocyte subtypes [keratinocyte stem cells, transit amplifying keratinocytes (TA), postmitotic differentiating keratinocytes (PMD)], and real-time polymerase chain reaction analysis was used to determine the abundance of IGFBP-3 and IGF-IR mRNAs. (ii) An IGFBP-3 transgenic mouse model was then used to assess the effect of excess epidermal IGFBP-3 on keratinocyte proliferation. Excess epidermal IGFBP-3 mRNA and protein was determined by in situ hybridization and immunohistochemistry, respectively. RESULTS: (i) The highest levels of IGFBP-3 mRNA were detected in TA keratinocytes, in contrast to IGF-IR mRNA levels which were highest in PMD keratinocytes. (ii) Elevated human IGFBP-3 mRNA and protein was confirmed in the epidermis of skin derived from transgenic mice. Excess IGFBP-3 reduced the relative percentage of proliferative keratinocytes (Ki67 positive) irrespective of skin location (belly, back and tail). Thus, in the epidermis, IGFBP-3 mRNA is highly expressed by proliferative keratinocytes (TA) and overexpression of IGFBP-3 inhibits keratinocyte proliferation. CONCLUSIONS: We conclude that in vivo IGFBP-3 ensures epidermal homeostasis via downregulation of keratinocyte proliferation, and thus modulates the early stages of keratinocyte differentiation.


Asunto(s)
Epidermis/metabolismo , Proteína 3 de Unión a Factor de Crecimiento Similar a la Insulina/metabolismo , Queratinocitos/metabolismo , Adulto , Animales , Proliferación Celular , Células Epidérmicas , Femenino , Regulación de la Expresión Génica , Homeostasis/fisiología , Humanos , Proteína 3 de Unión a Factor de Crecimiento Similar a la Insulina/genética , Proteína 3 de Unión a Factor de Crecimiento Similar a la Insulina/fisiología , Queratinocitos/citología , Ratones , Ratones Transgénicos , Persona de Mediana Edad , Reacción en Cadena de la Polimerasa/métodos , ARN Mensajero/genética , Receptor IGF Tipo 1/genética , Receptor IGF Tipo 1/metabolismo
10.
Biotechniques ; 35(2): 332-9, 2003 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-12951775

RESUMEN

Transfection analyses are an informative method to assess the activity of specific promoter or enhancer elements in mammalian cells. Commercially available reporter vectors can be extremely useful investigative tools for such studies. This study reports that the pCAT 3- and pGL3-promoter vectors display cryptic responsiveness to androgens when they contain a DNA insert, while the empty vector, a commonly used negative control, is nonresponsive. Our studies initially aimed to characterize novel androgen-responsive DNA sequences in human genomic DNA through transactivational analyses. An isolated DNA fragment, designated ARC-3, contained three putative androgen response element "half-sites" and was androgen-responsive when cloned into the pCAT3-promoter vector. While we originally believed this to be a novel enhancer element, subsequent analyses of this clone revealed that this vector displays cryptic activity in the presence of an androgen. This was confirmed by cloning several unrelated DNA fragments that did not contain any known classic response elements into the pCAT3-promoter vector, all of which were found to be responsive. The empty vector (negative control) was again nonresponsive. The ARC-3 DNA fragment was also weakly responsive to stimulation when cloned into the pGL3-promotor vector, which is identical to the pCAT3-promoter vector, with the exception of an intron located 5' of the chloramphenicol acetyltransferase gene, and the reporter genes. This work demonstrates that both the pCAT3- and pGL3-promoter vectors are inappropriate to assess androgen-responsive enhancers and emphasizes the importance of the careful selection of reporter vectors and controls when conducting transactivational analysis.


Asunto(s)
Cloranfenicol O-Acetiltransferasa/genética , Genes Reporteros , Vectores Genéticos , Regiones Promotoras Genéticas , Receptores Androgénicos/metabolismo , Animales , Secuencia de Bases , Línea Celular , Cloranfenicol O-Acetiltransferasa/química , Chlorocebus aethiops , Secuencia de Consenso , ADN/química , Elementos de Facilitación Genéticos , Células Epiteliales/efectos de los fármacos , Expresión Génica/efectos de los fármacos , Intrones , Riñón/citología , Metribolona/farmacología , Mutagénesis Sitio-Dirigida , Plásmidos , Receptores Androgénicos/química , Receptores Androgénicos/efectos de los fármacos , Receptores Androgénicos/genética , Receptores de Glucocorticoides/genética , Eliminación de Secuencia , Activación Transcripcional , Transfección
11.
Acta Crystallogr D Biol Crystallogr ; 59(Pt 7): 1320-2, 2003 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-12832799

RESUMEN

The gene for the DNA-binding protein Sso10a from the hyperthermophilic archaeon Sulfolobus solfataricus was cloned and overexpressed in Escherichia coli. Crystals of the purified protein have been grown that diffract to beyond 2.15 A resolution. The protein crystals belong to the orthorhombic space group P2(1)2(1)2(1), with unit-cell parameters a = 57.24, b = 60.16, c = 69.96 A. With one dimer per asymmetric unit, the crystal to volume per protein mass (V(M)) is 2.9 A(3) Da(-1) and the solvent content is approximately 57%. Complete X-ray diffraction native data were collected from a single crystal and processed to 2.15 A.


Asunto(s)
Proteínas de Unión al ADN/química , Sulfolobus/química , Secuencia de Aminoácidos , Proteínas Arqueales/química , Proteínas Arqueales/genética , Proteínas Arqueales/aislamiento & purificación , Clonación Molecular , Cristalización , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/aislamiento & purificación , Alineación de Secuencia , Difracción de Rayos X
15.
J Invest Dermatol ; 116(4): 491-7, 2001 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-11286613

RESUMEN

The insulin-like growth factor (IGF) system is essential for epidermal homeostasis. Insulin-like growth factor binding protein 3 (IGFBP-3), a modulator of IGF action that also exhibits IGF-independent activity, is localized to selected keratinocytes in the basal epidermal layer and may thus contribute to keratinocyte differentiation. We have utilized the human keratinocyte cell line, HaCaT, to examine the effect of calcium on the regulation of components of the IGF system. Western ligand and northern blot analyses revealed secreted IGFBP-3 and IGFBP-3 mRNA were reduced by an elevation in calcium levels in the culture medium. At 1.0 and 1.2 mM CaCl2 culture conditions IGFBP-3 abundance was reduced to 36% +/- 1.6% and 26% +/- 7.1%, respectively, of that from cells grown at 0.03 mM CaCl2. IGFBP-3 mRNA levels in 0.7 mM and 1.2 mM CaCl2 were reduced to 46% +/- 17.4% and 24% +/- 4.6%, respectively, compared with IGFBP-3 mRNA levels at 0.03 mM CaCl2. The observed reduction of IGFBP-3 was not associated with IGFBP-3 proteolysis. In contrast IGF-I receptor protein and mRNA levels remained unchanged. The IGF-I stimulated proliferative response of HaCaT keratinocytes showed that under low (0.03 mM) and high (1.2 mM) CaCl2 conditions IGF-I at 100 and 1000 ng per ml similarly increased cell number 2.4- and 2.7-fold, respectively, with similar dose-response curves. HaCaT keratinocytes grown under medium (0.7 mM) and high (1.2 mM), but not low (0.03 mM), CaCl2 conditions for 21 d revealed an induction of profilaggrin mRNA, a marker of keratinocyte differentiation. These studies indicate that the exposure of HaCaT keratinocytes to elevated calcium levels is associated with a decline in IGFBP-3 but not IGF-I receptor levels. These findings suggest a potential mechanism for the distribution of IGFBP-3 in the epidermis, which may be involved in the process of keratinocyte differentiation.


Asunto(s)
Calcio/fisiología , Proteína 3 de Unión a Factor de Crecimiento Similar a la Insulina/metabolismo , Queratinocitos/metabolismo , Calcio/metabolismo , Calcio/farmacología , División Celular/efectos de los fármacos , Línea Celular , Células Cultivadas , Relación Dosis-Respuesta a Droga , Endopeptidasas/metabolismo , Inducción Enzimática/fisiología , Proteínas Filagrina , Humanos , Proteína 3 de Unión a Factor de Crecimiento Similar a la Insulina/genética , Factor I del Crecimiento Similar a la Insulina/farmacología , Proteínas de Filamentos Intermediarios/genética , Queratinocitos/efectos de los fármacos , Precursores de Proteínas/genética , ARN Mensajero/metabolismo , Receptor IGF Tipo 1/genética , Receptor IGF Tipo 1/metabolismo , Receptor IGF Tipo 1/fisiología
16.
Protein Sci ; 9(10): 1878-88, 2000 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-11106160

RESUMEN

Sac7d unfolds at low pH in the absence of salt, with the greatest extent of unfolding obtained at pH 2. We have previously shown that the acid unfolded protein is induced to refold by decreasing the pH to 0 or by addition of salt (McCrary BS, Bedell J. Edmondson SP, Shriver JW, 1998, J Mol Biol 276:203-224). Both near-ultraviolet circular dichroism spectra and ANS fluorescence enhancements indicate that the acid- and salt-induced folded states have a native fold and are not molten globular. 1H,15N heteronuclear single quantum coherence NMR spectra confirm that the native, acid-, and salt-induced folded states are essentially identical. The most significant differences in amide 1H and 15N chemical shifts are attributed to hydrogen bonding to titrating carboxyl side chains and through-bond inductive effects. The 1H NMR chemical shifts of protons affected by ring currents in the hydrophobic core of the acid- and salt-induced folded states are identical to those observed in the native. The radius of gyration of the acid-induced folded state at pH 0 is shown to be identical to that of the native state at pH 7 by small angle X-ray scattering. We conclude that acid-induced collapse of Sac7d does not lead to a molten globule but proceeds directly to the native state. The folding of Sac7d as a function of pH and anion concentration is summarized with a phase diagram that is similar to those observed for other proteins that undergo acid-induced folding except that the A-state is encompassed by the native state. These results demonstrate that formation of a molten globule is not a general property of proteins that are refolded by acid.


Asunto(s)
Proteínas Arqueales , Proteínas de Unión al ADN/química , Pliegue de Proteína , Secuencia de Aminoácidos , Animales , Proteínas Bacterianas/química , Bovinos , Dicroismo Circular , Concentración de Iones de Hidrógeno , Lactalbúmina/química , Modelos Moleculares , Resonancia Magnética Nuclear Biomolecular , Conformación Proteica , Desnaturalización Proteica , Estructura Secundaria de Proteína , Proteínas Recombinantes/química , Espectrometría de Fluorescencia , Difracción de Rayos X
17.
J Mol Biol ; 303(3): 395-403, 2000 Oct 27.
Artículo en Inglés | MEDLINE | ID: mdl-11031116

RESUMEN

Sso7d and Sac7d are two small chromatin proteins from the hyperthermophilic archaeabacterium Sulfolobus solfataricus and Sulfolobus acidocaldarius, respectively. The crystal structures of Sso7d-GTGATCGC, Sac7d-GTGATCGC and Sac7d-GTGATCAC have been determined and refined at 1.45 A, 2.2 A and 2.2 A, respectively, to investigate the DNA binding property of Sso7d/Sac7d in the presence of a T-G mismatch base-pair. Detailed structural analysis revealed that the intercalation site includes the T-G mismatch base-pair and Sso7d/Sac7d bind to that mismatch base-pair in a manner similar to regular DNA. In the Sso7d-GTGATCGC complex, a new inter-strand hydrogen bond between T2O4 and C14N4 is formed and well-order bridging water molecules are found. The results suggest that the less stable DNA stacking site involving a T-G mismatch may be a preferred site for protein side-chain intercalation.


Asunto(s)
Proteínas Arqueales , Disparidad de Par Base/genética , Proteínas de Unión al ADN/química , Proteínas de Unión al ADN/metabolismo , ADN/metabolismo , Sulfolobus/química , Secuencia de Aminoácidos , Emparejamiento Base , Secuencia de Bases , Sitios de Unión , Proteínas Cromosómicas no Histona/química , Proteínas Cromosómicas no Histona/metabolismo , Cristalografía por Rayos X , ADN/química , ADN/genética , Enlace de Hidrógeno , Sustancias Intercalantes/química , Sustancias Intercalantes/metabolismo , Modelos Moleculares , Datos de Secuencia Molecular , Unión Proteica , Estructura Secundaria de Proteína , Alineación de Secuencia , Electricidad Estática , Sulfolobus acidocaldarius/química , Agua/metabolismo
18.
Kidney Int ; 58(1): 62-70, 2000 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-10886550

RESUMEN

BACKGROUND: Children with chronic renal failure (CRF) exhibit growth retardation and a disturbed growth hormone/insulin-like growth factor-I (GH/IGF-I) axis. Treatment of children with CRF with GH or GH/IGF-I can partially restore linear growth. The molecular basis for decreased longitudinal growth is not known but may involve an impaired action of GH. METHODS: We used the growth-retarded uremic rat model to determine the abundance and distribution of GH receptors (GHRs) in the tibial epiphyseal growth plate and the influence of GH, IGF-I, or combined GH/IGF-I treatment. Pair-fed rats were used as the control. RESULTS: While all treatment regimes increased body length and weight in both rat groups, only GH/IGF-I treatment increased the total growth plate width. This involved an increase in cell number in the hypertrophic zone, which could also be induced by IGF-I alone. Immunohistochemical analysis showed that uremic rats had decreased abundance of GHRs in the proliferative zone, and only GH/IGF-I therapy could overcome this decrease. These data thus suggest that growth retardation in uremic rats is, at least in part, due to a decrease in GHR abundance in chondrocytes of the proliferative zone of the tibial growth plate. This decreased GHR abundance can be overcome by combined GH/IGF-I therapy, thus enhancing generation and proliferation of hypertrophic zone chondrocytes and increasing growth-plate width. CONCLUSION: These studies point to a mechanism for the growth retardation seen in children with CRF, and suggest that combined GH/IGF-I treatment may provide more effective therapy for these patients than GH alone.


Asunto(s)
Hormona del Crecimiento/farmacología , Placa de Crecimiento/química , Factor I del Crecimiento Similar a la Insulina/farmacología , Receptores de Somatotropina/análisis , Tibia/química , Uremia/fisiopatología , Animales , Peso Corporal , Condrocitos/química , Modelos Animales de Enfermedad , Femenino , Trastornos del Crecimiento/tratamiento farmacológico , Placa de Crecimiento/citología , Fallo Renal Crónico/tratamiento farmacológico , Fallo Renal Crónico/fisiopatología , Ratas , Ratas Sprague-Dawley , Tibia/citología , Tibia/crecimiento & desarrollo , Uremia/tratamiento farmacológico
19.
Nat Biotechnol ; 18(5): 521-6, 2000 May.
Artículo en Inglés | MEDLINE | ID: mdl-10802619

RESUMEN

Epidermal hyperplasia is a key feature of the common skin disorder psoriasis. Stimulation of epidermal keratinocytes by insulin-like growth factor I (IGF-I) is essential for cell division, and increased sensitivity to IGF-I may occur in psoriasis. We hypothesized that inhibition of IGF-I receptor expression in the psoriasis lesion would reverse psoriatic epidermal hyperplasia by slowing the rate of keratinocyte cell division. Here we report the use of C5-propynyl-dU,dC-phosphorothioate antisense oligonucleotides to inhibit IGF-I receptor expression in keratinocytes. We identified several inhibitory antisense oligonucleotides and demonstrated IGF-I receptor inhibition in vitro through an mRNA targeting mechanism. Repeated injection of these oligonucleotides into human psoriasis lesions, grafted onto nude mice, caused a dramatic normalization of the hyperplastic epidermis. The findings indicate that IGF-I receptor stimulation is a rate-limiting step in psoriatic epidermal hyperplasia and that IGF-I receptor targeting by cutaneous administration of antisense oligonucleotides forms the basis of a potential new psoriasis therapy.


Asunto(s)
Epidermis/patología , Oligonucleótidos Antisentido/uso terapéutico , Psoriasis/tratamiento farmacológico , Receptor IGF Tipo 1/genética , Animales , Humanos , Hiperplasia , Inyecciones Intradérmicas , Queratinocitos/citología , Queratinocitos/efectos de los fármacos , Ratones , Ratones Endogámicos CBA , Ratones Desnudos , ARN Mensajero/aislamiento & purificación , Receptor IGF Tipo 1/análisis , Trasplante de Piel , Trasplante Heterólogo
20.
Genome Res ; 10(1): 30-41, 2000 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-10645947

RESUMEN

Centromere protein B (CENP-B) binds constitutively to mammalian centromere repeat DNA and is highly conserved between humans and mouse. Cenpb null mice appear normal but have lower body and testis weights. We demonstrate here that testis-weight reduction is seen in male null mice generated on three different genetic backgrounds (denoted R1, W9.5, and C57), whereas body-weight reduction is dependent on the genetic background as well as the gender of the animals. In addition, Cenpb null females show 31%, 33%, and 44% reduced uterine weights on the R1, W9.5, and C57 backgrounds, respectively. Production of "revertant" mice lacking the targeted frameshift mutation but not the other components of the targeting construct corrected these differences, indicating that the observed phenotype is attributable to Cenpb gene disruption rather than a neighbouring gene effect induced by the targeting construct. The R1 and W9.5 Cenpb null females are reproductively competent but show age-dependent reproductive deterioration leading to a complete breakdown at or before 9 months of age. Reproductive dysfunction is much more severe in the C57 background as Cenpb null females are totally incompetent or are capable of producing no more than one litter. These results implicate a further genetic modifier effect on female reproductive performance. Histology of the uterus reveals normal myometrium and endometrium but grossly disrupted luminal and glandular epithelium. Tissue in situ hybridization demonstrates high Cenpb expression in the uterine epithelium of wild-type animals. This study details the first significant phenotype of Cenpb gene disruption and suggests an important role of Cenpb in uterine morphogenesis and function that may have direct implications for human reproductive pathology.


Asunto(s)
Autoantígenos , Proteínas Cromosómicas no Histona/deficiencia , Proteínas de Unión al ADN , Útero/anomalías , Animales , Peso Corporal/genética , Línea Celular , Centrómero/genética , Proteína B del Centrómero , Quimera/genética , Proteínas Cromosómicas no Histona/biosíntesis , Epitelio/metabolismo , Epitelio/patología , Femenino , Mutación del Sistema de Lectura/genética , Humanos , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Mutagénesis Sitio-Dirigida , Tamaño de los Órganos/genética , Reproducción/genética , Testículo/crecimiento & desarrollo , Testículo/metabolismo , Útero/crecimiento & desarrollo
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