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1.
Tech Coloproctol ; 15(2): 159-64, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21538014

RESUMEN

BACKGROUND: The etiology of anal incontinence (AI) is often multifactorial. There is little data on the relationship between the etiology of AI, symptom severity, and the need for surgery. The aim of our study was to investigate this association in a large number of unselected patients with AI referred to a tertiary specialist coloproctological practice. METHODS: Patients with AI seen at our unit between 1983 and 2008 were analyzed. The main etiologies were categorized as congenital, traumatic, neurologic, idiopathic, post-operative, post-obstetric, secondary to rectal prolapse, or inflammatory bowel disease. The severity of AI was graded using the validated Pescatori incontinence scale. RESULTS: Overall, 1,046 patients were studied. The AI score was higher in patients with congenital (4.7 ± 1.1), traumatic (4.6 ± 1.4), and neurological (4.4 ± 1.2) incontinence. Surgical treatment was indicated in 214 cases (20.5%). Patients with AI related to trauma and congenital anomalies required surgery in 43.5 and 31.4% of cases, respectively, a percentage significantly higher than that for patients with other etiologies (P = 0.002). Prolapse-related AI usually responded to correction of the prolapse. CONCLUSIONS: Patients with congenital, traumatic, and neurological AI tend to have greater symptom severity. Traumatic, rectal prolapse-related, and congenital AI cases more often require surgery.


Asunto(s)
Incontinencia Fecal/cirugía , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Preescolar , Incontinencia Fecal/congénito , Incontinencia Fecal/etiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Índice de Severidad de la Enfermedad , Adulto Joven
3.
J Anim Physiol Anim Nutr (Berl) ; 95(3): 286-93, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-20880285

RESUMEN

This study examined the effect of exercising horses five times per fortnight with two bouts of 5 min duration at their v(10) with 2 days between consecutive exercise sessions. Five Anglo-Arabian horses were treadmill-conditioned for 6 weeks. A standardized exercise test (SET) was performed at the beginning of the conditioning period (CP) to determine the blood lactate-running speed (BLRS) and the heart rate-running speed (HRRS) relationship and the SET was repeated every 2 weeks. After each SET, the BLRS relation was used to calculate the horse's speed (v = velocity), which produced a blood lactate concentration (LA) of 10 mmol/l (v(10) ) and 4 mmol/l (v(4) ). From the HRRS was calculated the speed at which the horses had a heart rate of 180 b/min (v(180) ). Each horse was then conditioned for the next 2 weeks five times at its individual v(10) for two 5-min bouts. Exercise speed was individually adapted to the new v(10) every 2 weeks. In addition, horses were submitted to another SET prescription to determine the peak oxygen consumption (VO(2 peak) ) before, after 3 weeks and at the end of CP. The v(4) of horses increased during the CP (p < 0.05). v(180) did not change (p > 0.05). VO(2 peak) increased in the first 3 weeks of CP (p < 0.05) and levelled off afterwards (p > 0.05). The conclusion drawn was that exercising horses five times per fortnight at their v(10) for two 5-min bouts with 2 days between consecutive exercise sessions improved v(4) and VO(2 peak) but not v(180).


Asunto(s)
Caballos/fisiología , Condicionamiento Físico Animal/fisiología , Animales , Frecuencia Cardíaca/fisiología , Caballos/sangre , Ácido Láctico/sangre , Factores de Tiempo
6.
Int J Colorectal Dis ; 21(2): 160-5, 2006 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-15947935

RESUMEN

BACKGROUND: Rectal internal mucosal prolapse (RIMP) may cause obstructed defaecation and encouraging short-term results have been reported after its transanal excision. The objective of this retrospective study was to assess both clinical and functional outcome after this procedure alone for patients presenting with evacuatory difficulty. PATIENTS AND METHODS: Forty patients (30 females, mean age 54 years), all suffering from obstructed defaecation, underwent RIMP excision at our unit during the last 11 years. RIMP was of first degree in three patients, of second degree in 21, and of third degree in 16 with 28/40 cases (70%) having associated anorectal pathology. The operation was carried out by hand suture (submucosal excision, Sarles endorectal excision, or the Delorme mucosectomy) in 26 patients, by circular stapled prolapsectomy in nine patients, or by combined manual and stapled techniques in five cases. Proctoscopy was carried out after 2 months for all patients, with anorectal manometry in 30 patients. Patients were independently assessed by state-trait anxiety scales for attendant anxiety and depression. RESULTS: Eighteen patients (45%) had significant postoperative complications with a surgical reintervention rate of 32.5%. Overall, 21 patients (52%) reported recurrent constipation and of these 14 (65%) had recurrent RIMP; six patients were treated successfully by rubber-band ligation alone. Two patients (5%) experienced new onset faecal incontinence. The recurrence rate of RIMP was unaffected by the type of operation, being 53% after manual techniques and 48% after combined procedures. There was no difference between postoperative manometric values in patients presenting with recurrent RIMP or constipation compared with those without RIMP or constipation on follow-up. Forty-eight percent of the patients with both recurrent constipation plus RIMP had manometric evidence of non-relaxing puborectalis syndrome compared with 26% with RIMP but without constipation (P<0.05). Ten of the 14 patients (71%) with anxiety and/or depression complained of recurrent constipation after surgery compared with nine of the 26 patients (24%) with normal psychological profiles (P<0.01). Patients with a preoperative rectocele were more likely to suffer from recurrent constipation than those without rectocele (eight out of 15, 53.3% vs. seven out of 25, 28%; P<0.05). CONCLUSIONS: Primary excision of RIMP does not seem an effective treatment for obstructed defecation with predictive factors for an adverse outcome in terms of recurrence (RIMP and constipation) including the presence of preoperative non-relaxing puborectalis syndrome and a demonstrated anxiety or depression psychological profile. The technique of prolapsectomy does not seem to affect outcome.


Asunto(s)
Estreñimiento/cirugía , Defecación/fisiología , Procedimientos Quirúrgicos del Sistema Digestivo/efectos adversos , Complicaciones Posoperatorias , Prolapso Rectal/cirugía , Adulto , Anciano , Estreñimiento/etiología , Estreñimiento/fisiopatología , Constricción Patológica/complicaciones , Constricción Patológica/cirugía , Femenino , Estudios de Seguimiento , Humanos , Persona de Mediana Edad , Pronóstico , Prolapso Rectal/complicaciones , Recurrencia
7.
Eur Biophys J ; 32(4): 329-41, 2003 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-12851791

RESUMEN

Proteins of the transferrin (Tf) family have a role in metal transport in vertebrates and have been extensively studied. The results here reported provide, for the first time, a detailed systematic comparison of metal sites in Tf complexes involving several atoms in the whole protein and in two different types of Tfs. The high interest in the structural variations induced in a metalloprotein upon the uptake of different metals is related to the hypothesis of the metals' involvement in some neuropathologies. We propose a comparative study of the X-ray absorption spectra at the K-edge of iron, copper, zinc and nickel in serotransferrin and ovotransferrin. The experimental data are simulated using an algorithm of the full multiple scattering method. Our results show that: (1) the local structure of each site (N-terminal and C-terminal) is correlated to the ligation state of the other site; (2) the difference between the two proteins is related to site local structure and depends on the metal ion nature being greater in the case of copper and zinc with respect to iron and nickel ions; (3) X-ray spectroscopy is confirmed as a suitable technique able to discriminate between coordination models proposed by X-ray diffraction.


Asunto(s)
Conalbúmina/química , Metales/química , Modelos Moleculares , Espectrometría por Rayos X/métodos , Transferrina/química , Animales , Sitios de Unión , Pollos , Simulación por Computador , Humanos , Unión Proteica , Conformación Proteica , Especificidad de la Especie
8.
Physiol Chem Phys Med NMR ; 35(1): 55-72, 2003.
Artículo en Inglés | MEDLINE | ID: mdl-15139283

RESUMEN

Dihydropyridines (DHPs), synthetic molecules used as antihypertensive agents, bind to plasma membrane receptors following diffusion through the hydrophobic phase. In this study, MRS technique has been used to clarify the interactions of the dihydrophyridines Nifedipine and Lacidipine within the lipid bilayer. 1D and 2D 1H MRS at high field have been employed to examine the behavior of unilamellar dimyristoyl-phosphatidylcholine liposomes when the two drugs have been inserted in the bilayer. In particular, the study represents an innovative application of 2D 1H NOESY technique to clarify different mechanisms of interactions of small molecules inside model membranes. On the other hand, 31P measurements have been performed in multilamellar dimyristoyl-phosphatidylcholine lipsomes to detect alterations of lipid polymorphic phases. The experiments show that the two dihydropyridines interact with the lipids by different modalities. Lacidipine undergoes a very strong interaction with lipids, possibly inducing a phase segregation of lipid molecules into the bilayer, while self-association seems to be the prevalent interaction of Nifedipine inside the bilayer.


Asunto(s)
Dihidropiridinas/química , Dimiristoilfosfatidilcolina/química , Lípidos/química , Liposomas/química , Dihidropiridinas/metabolismo , Dimiristoilfosfatidilcolina/metabolismo , Metabolismo de los Lípidos , Liposomas/metabolismo , Espectroscopía de Resonancia Magnética , Estructura Molecular , Nifedipino/química
9.
Equine Vet J Suppl ; (34): 275-8, 2002 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-12405700

RESUMEN

Apoptosis or programmed cell death is a genetically controlled response of cells to commit suicide and is associated with DNA fragmentation or laddering. The common inducers of apoptosis include Ca2+i and oxygen free radicals/oxidative stress, which are also implicated in the pathogenesis of exercise-induced myopathies. To examine training-induced apoptosis, Thoroughbred horses were subjected to 3 months training programme on a treadmill. At the end of the training programme venous blood samples were taken for a creatine kinase (CK) assay. In addition, muscle biopsy samples were obtained for a membrane lipid peroxidation measurement by malondialdehyde (MDA) assay and for apoptosis detection. Apoptosis was studied by visualising the apoptotic myocytes on the paraffin sections by the modified TUNEL method. DNA laddering was evaluated by subjecting the DNA obtained from the biopsies to 1.5% agarose gel electrophoresis. There was a significant increase (P<0.05) of protein-bound MDA, and a nonsignificant trend (P = 0.14) for the control group to have higher levels of CK compared to the trained group. Under light microscopy, percentage of the TUNEL positive cells was higher (P<0.001) in the training group. This result was corroborated with the findings of DNA fragmentation by gel electrophoresis, which showed higher ladders of DNA band at the same group. In conclusion, these results clearly demonstrate that there is training-induced apoptosis in skeletal muscle. It is probable that apoptosis allows the work/recovery/rebound/supercompensation cycle, when unaccustomed muscle cells activate programmed cell death and are replaced by new and stronger cells, which is the mechanism for training-induced increases in fitness.


Asunto(s)
Apoptosis , Caballos/fisiología , Músculo Esquelético/citología , Condicionamiento Físico Animal/fisiología , Animales , Biopsia/veterinaria , Creatina Quinasa/sangre , Fragmentación del ADN , Electroforesis en Gel de Agar/veterinaria , Prueba de Esfuerzo/veterinaria , Femenino , Etiquetado Corte-Fin in Situ/veterinaria , Peroxidación de Lípido/fisiología , Masculino , Malondialdehído/metabolismo , Músculo Esquelético/fisiología , Distribución Aleatoria
11.
J Synchrotron Radiat ; 8(Pt 2): 196-8, 2001 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-11512724

RESUMEN

The active metal site structure of transferrin with iron and copper atoms is investigated using metal K-XANES. Theoretical analysis of experimental data has been performed on the basis of full multiple-scattering theory. This approach made it possible to study the origin of XANES fine details and to investigate the local structure around active metal sites. A deep insight into the local structure and electronic subsystem of Fe, Cu transferrins is obtained. For example, in the case of Cu substitution of Fe in the active centre, the best fit of theoretical spectra to experiment has been obtained for distances 3% smaller between the Cu atom and the nearest neighbours.


Asunto(s)
Conalbúmina/química , Cobre/química , Hierro/química , Transferrina/química , Animales , Sitios de Unión , Pollos , Femenino , Humanos , Espectrometría por Rayos X/métodos
12.
Biophys J ; 80(3): 1473-9, 2001 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-11222307

RESUMEN

We have studied, using x-ray absorption spectroscopy by synchrotron radiation, the native state of the horse heart cytochrome c (N), the HCl denatured state (U(1) at pH 2), the NaOH denatured state (U(2) at pH 12), the intermediate HCl induced state (A(1) at pH 0.5), and the intermediate NaCl induced state (A(2) at pH 2). Although many results concerning the native and denatured states of this protein have been published, a site-specific structure analysis of the denatured and intermediate solvent induced states has never been attempted before. Model systems and myoglobin in different states of coordination are compared with cytochrome c spectra to have insight into the protein site structure in our experimental conditions. New features are evidenced by our results: 1) x-ray absorption near edge structure (XANES) of the HCl intermediate state (A(1)) presents typical structures of a pentacoordinate Fe(III) system, and 2) local site structures of the two intermediate states (A(1) and A(2)) are different.


Asunto(s)
Grupo Citocromo c/química , Concentración de Iones de Hidrógeno , Absorciometría de Fotón , Animales , Hemina/química , Caballos , Ácido Clorhídrico , Desnaturalización Proteica , Hidróxido de Sodio , Espectrofotometría
13.
Biometals ; 13(3): 217-22, 2000 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-11127893

RESUMEN

The Cu site structure of human serotransferrin and hen ovotransferrin using XANES spectroscopy has been investigated. Although the transferrin family proteins have been extensively studied, the results reported herein are the first concerning the structure of the metal site in C-terminal and N-terminal in the whole protein. Our structural data show that these proteins differ with regard to the independence of the two binding sites and the geometry of copper coordination, ranging from a poorly to a significantly distorted octahedron.


Asunto(s)
Conalbúmina/química , Cobre/química , Transferrina/química , Animales , Sitios de Unión , Pollos , Humanos , Fragmentos de Péptidos/química , Espectrometría por Rayos X , Espectrofotometría Ultravioleta
14.
Free Radic Res ; 31(1): 1-8, 1999 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-10489115

RESUMEN

To mimic exercise-induced events such as energetic impairment, free radical generation, and lipid peroxidation in vitro, mouse-derived C2C12 myotubes were submitted to the inhibition of glycolytic and/or oxidative metabolism with 1 mM iodoacetate (IAA) and/or 2 mM sodium cyanide (CN), respectively, under 5% CO2/95% air up to 180 min. Electron spin resonance (ESR) analysis with a spin-trap 5,5-dimethyl-1-pyrroline-N-oxide (DMPO) revealed time-course increases in spin adducts from hydroxyl radical (DMPO-OH) and carbon-centered radical (DMPO-R) in the supernatant of C2C12 myotubes treated with the combination of IAA + CN. In this condition, malondialdehyde (MDA) and lactate dehydrogenase (LDH) were released into the supernatant. By the addition of iron-chelating 1 mM deferoxamine to the C2C12 preparation with IAA + CN, both ESR signals of DMPO-OH and DMPO-R were completely abolished, and the release of MDA and LDH were significantly reduced, while cyanide-resistant manganese superoxide dismutase had negligible effects on these parameters. Hence, a part of the injury of C2C12 myotube under IAA + CN was considered to result from the lipid peroxidation, which was induced by hydroxyl radical generated from iron-catalyzed systems such as the Fenton-type reaction. This in vitro model would be a helpful tool for investigating the free radical-related muscle injury.


Asunto(s)
Radical Hidroxilo/metabolismo , Yodoacetatos/farmacología , Peroxidación de Lípido , Músculo Esquelético/efectos de los fármacos , Músculo Esquelético/metabolismo , Cianuro de Sodio/farmacología , Animales , Línea Celular , Óxidos N-Cíclicos , Deferoxamina/farmacología , Resistencia a Medicamentos , Espectroscopía de Resonancia por Spin del Electrón , Quelantes del Hierro/farmacología , Cinética , L-Lactato Deshidrogenasa/metabolismo , Malondialdehído/metabolismo , Ratones , Marcadores de Spin , Superóxido Dismutasa/farmacología
15.
Eur Biophys J ; 27(1): 1-7, 1998.
Artículo en Inglés | MEDLINE | ID: mdl-9463885

RESUMEN

We present the results of a comparative study of the binding of carbon monoxide to myoglobin in glycerol/buffer solution with different concentrations of guanidine hydrochloride, under extended illumination over the temperature range 30-80 K. The changes in the Soret band indicate that the folding state of the protein is a key parameter in determining the photodissociation process and the relaxation rate of the protein.


Asunto(s)
Guanidina/farmacología , Luz , Mioglobina/química , Mioglobina/metabolismo , Animales , Monóxido de Carbono/química , Monóxido de Carbono/metabolismo , Caballos , Cinética , Fotólisis , Desnaturalización Proteica , Espectrofotometría/métodos
16.
Z Naturforsch C J Biosci ; 52(9-10): 645-53, 1997.
Artículo en Inglés | MEDLINE | ID: mdl-9373995

RESUMEN

We found, by circular dichroism and Raman spectroscopy measurements, that the secondary structure of the native ovalbumin and of its heat-stable form, called S-ovalbumin, is a probe of the structural differences between the two proteins. Small angle X-ray scattering and circular dichroism measurements performed on the two proteins under denaturing conditions, with different concentrations of guanidine hydrochloride, show the changes of the tertiary and secondary structure and a different pathway in the unfolding process. These experimental data confirm that the conversion of native ovalbumin into S-ovalbumin is irreversible and reveal that the response of the two proteins to the same chemical environment is different.


Asunto(s)
Ovalbúmina/química , Animales , Pollos , Guanidina , Calor , Conformación Proteica , Desnaturalización Proteica , Dispersión de Radiación , Espectrometría Raman/métodos , Termodinámica
17.
Biometals ; 10(4): 363-7, 1997 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-9353887

RESUMEN

The Al site structure of serum transferrin and lactoferrin is investigated using X-ray absorption near edge structure (XANES) spectroscopy. Al K-edge spectra in the mono- and dialuminum forms of the proteins have been recorded for the first time. Our results show that the aluminium ion is hexa-coordinated in an octahedral-like symmetry and that the monoaluminum form, where only the C-terminal binding site is saturated, has an increased structural distortion around the metal site.


Asunto(s)
Aluminio/análisis , Lactoferrina/química , Transferrina/química , Aluminio/química , Sitios de Unión , Espectrometría por Rayos X
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