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1.
BMC Womens Health ; 23(1): 397, 2023 07 29.
Artículo en Inglés | MEDLINE | ID: mdl-37516869

RESUMEN

BACKGROUND: Endometrial scratching (ES) or injury is intentional damage to the endometrium performed to improve reproductive outcomes for infertile women desiring pregnancy. Moreover, recent systematic reviews with meta-analyses and randomized controlled trials demonstrated that ES is not effective, data on the safety are limited, and it should not be recommended in clinical practice. The aim of the current study was to assess the view and behavior towards ES among fertility specialists throughout infertility centers in Italy, and the relationship between these views and the attitudes towards the use of ES as an add-on in their commercial setting. METHODS: Online survey among infertility centers, affiliated to Italian Society of Human Reproduction (SIRU), was performed using a detailed questionnaire including 45 questions with the possibility to give "closed" multi-choice answers for 41 items and "open" answers for 4 items. Online data from the websites of the infertility centers resulting in affiliation with the specialists were also recorded and analyzed. The quality of information about ES given on infertility centers websites was assessed using a scoring matrix including 10 specific questions (scored from 0 to 2 points), and the possible scores ranged from 0 to 13 points ('excellent' if the score was 9 points or more, 'moderate' if the score was between 5 and 8, and 'poor' if it was 4 points or less). RESULTS: The response rate was of 60.6% (43 questionnaires / 71 infertility SIRU-affiliated centers). All included questionnaires were completed in their entirety. Most physicians (~ 70%) reported to offer ES to less than 10% of their patients. The procedure is mainly performed in the secretory phase (69.2%) using pipelle (61.5%), and usually in medical ambulatory (56.4%) before IVF cycles to improve implantation (71.8%) without drugs administration (e.g., pain drugs, antibiotics, anti-hemorrhagics, or others) before (76.8%) or after (64.1%) the procedure. Only a little proportion of infertility centers included in the analysis proposes formally the ES as an add-on procedure (9.3%), even if, when proposed, the full description of the indications, efficacy, safety, and costs is never addressed. However, the overall information quality of the websites was generally "poor" ranging from 3 to 8 and having a low total score (4.7 ± 1.6; mean ± standard deviation). CONCLUSIONS: In Italy, ES is a procedure still performed among fertility specialists for improving the implantation rate in IVF patients. Moreover, they have a poor attitude in proposing ES as an add-on in the commercial setting.


Asunto(s)
Infertilidad Femenina , Femenino , Embarazo , Humanos , Infertilidad Femenina/terapia , Fertilidad , Italia , Endometrio , Actitud
2.
J Inorg Biochem ; 178: 70-86, 2018 01.
Artículo en Inglés | MEDLINE | ID: mdl-29078150

RESUMEN

Neuroglobin is a monomeric globin containing a six-coordinate heme b, expressed in the nervous system, which exerts an important neuroprotective role. In the human protein (hNgb), Cys46 and Cys55 form an intramolecular disulfide bond under oxidizing conditions, whose cleavage induces a helix-to-strand rearrangement of the CD loop that strengthens the bond between the heme iron and the distal histidine. Hence, it is conceivable that the intramolecular disulfide bridge modulates the functionality of human neuroglobin by controlling exogenous ligand binding. In this work, we investigated the influence of the Cys46/Cys55 disulfide bond on the redox properties and on the pH-dependent conformational equilibria of hNgb, using UV-vis spectroelectrochemistry, cyclic voltammetry, electronic absorption spectroscopy and magnetic circular dichroism (MCD). We found that the SS bridge significantly affects the heme Fe(III) to Fe(II) reduction enthalpy (ΔH°'rc) and entropy (ΔS°'rc), mostly as a consequence of changes in the reduction-induced solvent reorganization effects, without affecting the axial ligand-binding interactions and the polarity and electrostatics of the heme environment. Between pH3 and 12, the electronic properties of the heme of ferric hNgb are sensitive to five acid-base equilibria, which are scarcely affected by the Cys46/Cys55 disulfide bridge. The equilibria occurring at extreme pH values induce heme release, while those occurring between pH5 and 10 alter the electronic properties of the heme without modifying its axial coordination and low spin state. They involve the sidechains of non-coordinating aminoacids close to the heme and at least one heme propionate.


Asunto(s)
Cisteína/química , Disulfuros/química , Globinas/química , Proteínas del Tejido Nervioso/química , Análisis Espectral , Electroquímica , Globinas/análisis , Hemo/química , Humanos , Concentración de Iones de Hidrógeno , Modelos Moleculares , Proteínas del Tejido Nervioso/análisis , Neuroglobina , Oxidación-Reducción , Espectrometría de Fluorescencia , Termodinámica
3.
Urologia ; 85(1): 34-35, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-28256702

RESUMEN

INTRODUCTION: Mesenchymal tumors are an exceptional finding in the urinary tract and renal leiomyoma is even more rare. They are usually discovered incidentally during ultrasonography examinations or autopsy. Sometimes they are clinically symptomatic with hematuria, flank pain, or palpable mass. Till today, it is still difficult to make a diagnosis of leiomyoma using the radiological examinations. Although conventional imaging has a high sensitivity and specificity in the detection of both retroperitoneal and renal masses, the diagnosis is based on histological examination, due to the poor discrimination accuracy between different retroperitoneal tumors. CASE DESCRIPTION: We report a case of renal leiomyoma in a 47-year-old woman, who incidentally discovered a retroperitoneal mass with an abdominal ultrasound scheduled for a conventional follow-up schedule of a mammary neoplasm. Partial nephrectomy was carried out with an open flank surgical approach and the diagnosis was "leiomyoma of the renal capsule". Four years after surgery, the patient is disease-free. CONCLUSIONS: Renal leiomyomas are rare, benign, nonmetastasizing tumors with a good prognosis after surgical treatment. At present, the differential diagnosis is still possible by histopathological examination.


Asunto(s)
Neoplasias Renales/diagnóstico por imagen , Neoplasias Renales/cirugía , Leiomioma/diagnóstico por imagen , Leiomioma/cirugía , Nefrectomía , Ultrasonografía , Animales , Neoplasias de la Mama/cirugía , Diagnóstico Diferencial , Femenino , Humanos , Hallazgos Incidentales , Persona de Mediana Edad , Factores de Riesgo , Resultado del Tratamiento , Ultrasonografía/métodos
4.
Cardiovasc Intervent Radiol ; 40(9): 1440-1446, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-28474112

RESUMEN

PURPOSE: To assess the feasibility and safety of transperineal laser ablation (TPLA) for treating benign prostatic hyperplasia (BPH). MATERIALS AND METHODS: Institutional review board approval was obtained for this prospective non-randomized trial. Eightteen patients (age 71.7 ± 9.4 years) with urinary symptoms secondary to BPH underwent TPLA under local anesthesia. Under US guidance, up to four 21G applicators were inserted in the prostatic tissue. Each treatment was performed with diode laser operating at 1064 nm changing the illumination time according to prostate size. Primary endpoints were technical success and safety of TPLA. Secondary endpoints included operation time, ablation time, energy deployed, hospitalization time, catheterization time, and change in International Prostate Symptom Score (IPSS), Quality of Life (QoL), peak urinary flow rate (Q max), post-void residual (PVR), and prostatic volume at 3 months. χ 2 and Fisher exact tests were used. RESULTS: All procedures were technically successful. No complications occurred. Mean operation time was 43.3 ± 8.7 min, mean ablation time 15.9 ± 3.9 min, mean energy deployed 10,522 ± 3290.5 J, mean hospital stay 1.5 ± 0.4 days, and mean catheterization time 17.3 ± 10.0 days. At 3 months, IPSS improved from 21.9 to 10.7 (P < 0.001), QoL from 4.7 ± 0.6 to 2.1 ± 1.2 (P < 0.001), Q max from 7.6 to 13.3 mL/s (P = 0.001), PVR from 199.9 ± 147.3 to 81.5 ± 97.8 (P < 0.001), and mean prostate volume from 69.8 to 54.8 mL (P < 0.001). CONCLUSIONS: TPLA is feasible and safe in the treatment of BPH, providing significant clinical results at 3 months. LEVEL OF EVIDENCE: Case series, Level IV.


Asunto(s)
Terapia por Láser/métodos , Procedimientos Quirúrgicos Mínimamente Invasivos/métodos , Hiperplasia Prostática/cirugía , Anciano , Anciano de 80 o más Años , Estudios de Factibilidad , Humanos , Masculino , Persona de Mediana Edad , Tempo Operativo , Perineo/cirugía , Estudios Prospectivos , Retención Urinaria/cirugía
5.
Phys Chem Chem Phys ; 15(32): 13499-505, 2013 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-23824165

RESUMEN

A bacterial di-heme cytochrome c binds electrostatically to a gold electrode surface coated with a negatively charged COOH-terminated SAM adopting a sort of 'perpendicular' orientation. Cyclic voltammetry, Resonance Raman and SERRS spectroscopies indicate that the high-potential C-terminal heme center proximal to the SAM's surface undergoes an adsorption-induced swapping of one axial His ligand with a water molecule, which is probably lost in the reduced form, and a low- to high-spin transition. This coordination change for a bis-His ligated heme center upon an electrostatically-driven molecular recognition is as yet unprecedented, as well as the resulting increase in reduction potential. We discuss it in comparison with the known methionine ligand lability in monoheme cytochromes c occurring upon interaction with charged molecular patches. One possible implication of this finding in biological ET is that mobile redox partners do not behave as rigid and invariant bodies, but in the ET complex are subjected to molecular changes and structural fluctuations that affect in a complex way the thermodynamics and the kinetics of the process.


Asunto(s)
Citocromos c/química , Hierro/química , Citocromos c/metabolismo , Electrodos , Oro/química , Oxidación-Reducción , Shewanella/enzimología , Electricidad Estática , Propiedades de Superficie
6.
Clin Chem Lab Med ; 49(8): 1289-1293, 2011 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-21679131

RESUMEN

BACKGROUND: An increased frequency of (cystic fibrosis transmembrane conductance regulator) CFTR mutations has been detected in some types of male infertility. The aim of this study was to shed light on the link between CFTR mutations and infertility. METHODS: We sequenced the CFTR gene in 294 subjects (190 males) affected by infertility of different origin who underwent assisted reproductive technology (ART). As a control group, we studied 1000 (353 males) unrelated, unselected subjects from the general population of southern Italy. RESULTS: The frequency of CFTR mutations, some of which are detected only by gene sequencing, and of the IVS8 poly(TG)12-poly(T)5-V470 haplotype was significantly higher in obstructive [congenital bilateral absence of vasa defer-entes (CBAVD, five cases)] and secretory (23 cases) azoospermic patients than in the general population. Some patients, primarily those with CBAVD, were compound heterozygous for two mutations. Interestingly, the frequency of the TG12-T5-V470 variant haplotype was significantly higher in severe oligospermic patients (88 cases) and in patients with tubal sterility (74 cases) compared with the general population. Finally, neither the frequency of CFTR mutations nor the frequency of the TG12-T5 variants differed between patients with mild oligospermia (74 cases) and patients with ovulatory sterility (30 cases) compared with the general population. CONCLUSIONS: All subjects affected by obstructive or secretory azoospermia should undergo molecular analysis and counselling for CF using gene scanning which has a high detection rate and also reveals rare CFTR mutations. Molecular analysis seems to be less mandatory in other types of male/female infertility. Furthermore, we found that the CFTR TG12-T5-V470 variant haplotype was associated with both severe oligospermia and tubal infertility, thereby implicating the CFTR protein in both spermatogenesis and tubal functionality.


Asunto(s)
Regulador de Conductancia de Transmembrana de Fibrosis Quística/genética , Técnicas Reproductivas Asistidas , Alelos , Azoospermia/genética , Frecuencia de los Genes , Asesoramiento Genético , Genotipo , Haplotipos , Humanos , Masculino , Enfermedades Urogenitales Masculinas/genética , Oligospermia/genética , Polimorfismo Genético , Análisis de Secuencia de ADN , Conducto Deferente/anomalías
7.
Langmuir ; 26(23): 17831-5, 2010 Dec 07.
Artículo en Inglés | MEDLINE | ID: mdl-21070064

RESUMEN

Mimochrome VI (MC-VI) is a synthetic heme peptide containing a helix-heme-helix sandwich motif designed to reproduce the catalytic activity of heme oxidases. The thermodynamics of Fe(III) to Fe(II) reduction and the kinetics of the electron-transfer process for MC-VI immobilized through hydrophobic interactions on a gold electrode coated with a nonpolar SAM of decane-1-thiol have been determined through cyclic voltammetry. Immobilization slightly affects the reduction potential of MC-VI, which under these conditions electrocatalytically turns over molecular oxygen. This work sets the premise for the exploitation of totally synthetic mimochrome-modified electrode surfaces for clinical and pharmaceutical biosensing.


Asunto(s)
Deuteroporfirinas/química , Electroquímica/métodos , Oro/química , Hemo/química , Metaloproteínas/química , Oxidación-Reducción , Péptidos/química , Adsorción , Secuencia de Aminoácidos , Catálisis , Citocromos c/química , Electrodos , Conformación Molecular , Datos de Secuencia Molecular , Oxígeno/química , Conformación Proteica
8.
RFO UPF ; 13(2): 61-65, maio-ago. 2008. ilus
Artículo en Portugués | LILACS, BBO - Odontología | ID: lil-497085

RESUMEN

O cisto paradental é uma lesão odontogênica que ocorre próxima à margem cervical da face lateral da raiz, como consequëncia de um processo inflamatório na bolsa periodontal. Geralmente, localiza-se nas faces vestibular e distal de terceiros molares inferiores parcial ou totalmente erupcionados. O objetivo deste trabalho foi relatar um caso de uma lesão óssea localizada na região distal de um terceiro molar inferior parcialmente erupcionado, descoberta aoexame radiográfico de uma paciente do sexo feminino que apresentava história de pericoronarite. O diagnóstico de cisto paradental foi definido após correlação dos achados e o diagnóstico diferencial do cisto paradental com outras lesões são também analisados.


Asunto(s)
Femenino , Adulto , Quistes Maxilomandibulares , Enfermedades Maxilomandibulares , Quistes Odontogénicos
9.
J Am Chem Soc ; 129(14): 4423-9, 2007 Apr 11.
Artículo en Inglés | MEDLINE | ID: mdl-17367139

RESUMEN

Plastocyanin is a small blue copper protein that shuttles electrons as part of the photosynthetic redox chain. Its redox behavior is changed at low pH as a result of protonation of the solvent-exposed copper-coordinating histidine. Protonation and subsequent redox inactivation could have a role in the down regulation of photosynthesis. As opposed to plastocyanin from other sources, in fern plastocyanin His90 protonation at low pH has been reported not to occur. Two possible reasons for that have been proposed: pi-pi stacking between Phe12 and His90 and lack of a hydrogen bond with the backbone oxygen of Gly36. We have produced this fern plastocyanin recombinantly and examined the properties of wild-type protein and mutants Phe12Leu, Gly36Pro, and the double mutant with NMR spectroscopy, X-ray crystallography, and cyclic voltammetry. The results demonstrate that, contrary to earlier reports, protonation of His90 in the wild-type protein does occur in solution with a pKa of 4.4 (+/-0.1). Neither the single mutants nor the double mutant exhibit a change in protonation behavior, indicating that the suggested interactions have no influence. The crystal structure at low pH of the Gly36Pro variant does not show His90 protonation, similar to what was found for the wild-type protein. The structure suggests that movement of the imidazole ring is hindered by crystal contacts. This study illustrates a significant difference between results obtained in solution by NMR and by crystallography.


Asunto(s)
Dryopteris/química , Histidina/análogos & derivados , Compuestos Organometálicos/química , Plastocianina/química , Protones , Amidas/química , Cristalografía por Rayos X , Glicina/genética , Glicina/metabolismo , Histidina/química , Concentración de Iones de Hidrógeno , Ligandos , Resonancia Magnética Nuclear Biomolecular , Oxidación-Reducción , Proteínas de Plantas/química , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo
10.
J Am Chem Soc ; 128(16): 5444-51, 2006 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-16620116

RESUMEN

Cyclic voltammetry experiments were carried out on native Saccharomyces cerevisiae iso-1-cytochrome c and its C102T/N62C variant immobilized on bare polycrystalline gold electrode through the S-Au bond formed by a surface cysteine. Experiments were carried out at different temperatures (5-65 degrees C) and pH values (1.5-7). The E degrees ' value at pH 7 (+370 mV vs SHE) is approximately 100 mV higher than that for the protein in solution. This difference is enthalpic in origin and is proposed to be the result of the electrostatic repulsion among the densely packed molecules onto the electrode surface. Two additional electrochemical waves are observed upon lowering the pH below 5 (E degrees ' = +182 mV) and 3 (E degrees ' = +71 mV), which are attributed to two conformers (referred to as "intermediate" and "acidic", respectively) featuring an altered heme axial ligation. This is the first determination of the reduction potential for low-pH conformers of cytochrome c in the absence of denaturants. Since the native form of cytochrome c can be restored, bringing back the pH to neutrality, the possibility offered by this transition to reversibly modulate the redox potential of cytochrome c is appealing for bioelectronic applications. The immobilized C102T/N62C variant, which differs from the native protein in the orientation of the heme group with respect to the electrode, shows very similar reduction thermodynamics. For both species, the rate constant for electron transfer between the heme and the electrode increases for the acidic conformer, which is also found to act as a biocatalytic interface for dioxygen reduction.


Asunto(s)
Citocromos c/química , Concentración de Iones de Hidrógeno , Proteínas de Saccharomyces cerevisiae/química , Saccharomyces cerevisiae/enzimología , Catálisis , Electroquímica , Cinética , Modelos Moleculares , Oxidación-Reducción , Termodinámica
11.
Biochemistry ; 44(29): 9944-9, 2005 Jul 26.
Artículo en Inglés | MEDLINE | ID: mdl-16026167

RESUMEN

In this work, we have determined the thermodynamic parameters of the reduction of four different variants of Thiobacillus versutus amicyanin by electrochemical techniques. In addition, the thermodynamic parameters were determined of the low-pH conformational change involving protonation of the C-terminal histidine ligand and the concomitant dissociation of this histidine from the Cu(I) ion. In these variants, the native C-terminal loop containing the Cys, His, and Met copper ligands has been replaced with the corresponding polypeptide segments of Pseudomonas aeruginosa azurin, Populus nigra plastocyanin, Alcaligenes faecalis S-6 pseudoazurin, and Thiobacillus ferrooxidans rusticyanin. For the reduction reaction, each loop invariably holds an entropic "memory" of the mother protein. The thermodynamics of the low-pH transition vary in a fashion that is species-dependent. When present, the memory effect again shows a large entropic component. In particular, loop elongation tends to favor the formation of the Cu(I)-His bond (hence disfavors His protonation, yielding lower pK(a) values) probably due to an increased flexibility of the loop in the reduced state. Overall, it appears that both reduction and low-pH transition are loop-responsive processes. The spacing between the ligands mostly affects the change in the conformational freedom that accompanies the reaction.


Asunto(s)
Sustitución de Aminoácidos/genética , Azurina/química , Proteínas Bacterianas/química , Termodinámica , Proteínas Bacterianas/genética , Cobre/química , Entropía , Concentración de Iones de Hidrógeno , Ligandos , Oxidación-Reducción , Conformación Proteica , Estructura Terciaria de Proteína/genética , Solventes , Electricidad Estática
12.
Arch Ital Urol Androl ; 75(1): 1-5, 2003 Mar.
Artículo en Italiano | MEDLINE | ID: mdl-12741336

RESUMEN

The choice of urinary diversion is conditioned to patient's disease, performance status, age and life style. Ureterointestinal anastomosis is a critical stage in urinary diversion, allowing urinary transit and preventing reflux. We have examined urinary diversion frequently used in our clinical practice. In ureterosigmoidostomy and MAINZ pouch II , ureterointestinal anastomosis isn't refluent. Ileal conduit, reserved to patient with advanced disease and/or low life expectation, normally the implantation is direct. In continent reservoir and orthotopic neobladder, detubularization produces low pressure. In these urinary diversion anti-reflux anastomosis isn't mandatory, because the risk of stenosis is higher. Urinary infection is an important criterion in choice of anastomosis. After all is emphasized that success of ureterointestinal implantation doesn't depend on surgeon's level of experience.


Asunto(s)
Derivación Urinaria , Colon/cirugía , Colon Sigmoide/cirugía , Constricción Patológica/etiología , Dilatación Patológica/etiología , Humanos , Complicaciones Posoperatorias , Reoperación , Ureterostomía , Derivación Urinaria/efectos adversos , Derivación Urinaria/métodos , Infecciones Urinarias/etiología
13.
Arch Ital Urol Androl ; 74(2): 90-4, 2002 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-12161944

RESUMEN

OBJECTIVE: The noninvasive method for estimating bladder weight (UEBW, Ultrasound Estimated Bladder Weight) can be used as a measure of bladder hypertrophy and may have clinical use for evaluating intravesical obstruction in male patients. The aim of this study was to assess whether, in patients with bladder outlet obstruction (BOO), tamsulosin treatment produced any significant change in UEBW. METHODS: 32 male patients with lower urinary tract symptoms (LUTS) suggestive of BOO [benign prostatic hyperflesia (BPH) was the apparent cause of BOO] were enrolled in an open pilot study. At baseline, physical examination, ECG, hematochemical tests, urine analysis, urine culture, urodynamics, urethrocystography, transrectal ultrasound, UEBW and symptom score were performed. Using the International Continence Society (ICS) nomogram, patients were assigned to three different groups: obstructed, not obstructed and equivocal. Only patients in the obstructed and equivocal categories were treated with tamsulosin 0.4 mg once daily for 6 months. Follow-up for all patients took place after 30 days, 3 and 6 months of treatment. RESULTS: In the obstructed group of patients, the decrease in UEBW was observed at 30 days and maintained up to 6 months, with a significantly improved Qmax. A statistically significant correlation was found between UEBW and postvoid residual urine (PVR) and Abrams-Griffith number (AG). CONCLUSIONS: The results of this study suggest a significant change in UEBW during tamsulosin treatment. The change observed might be suggestive of a therapeutic effect of tamsulosin on the detrusor muscle. Further and more extensive studies are needed in order to confirm a possible therapeutic effect of tamsulosin on the detrusor muscle.


Asunto(s)
Antagonistas Adrenérgicos alfa/uso terapéutico , Hiperplasia Prostática/tratamiento farmacológico , Sulfonamidas/uso terapéutico , Vejiga Urinaria/patología , Antagonistas Adrenérgicos alfa/farmacología , Anciano , Antropometría/métodos , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Músculo Liso/diagnóstico por imagen , Músculo Liso/efectos de los fármacos , Músculo Liso/patología , Tamaño de los Órganos , Proyectos Piloto , Hiperplasia Prostática/complicaciones , Hiperplasia Prostática/diagnóstico por imagen , Sulfonamidas/farmacología , Tamsulosina , Ultrasonografía , Vejiga Urinaria/diagnóstico por imagen , Obstrucción del Cuello de la Vejiga Urinaria/diagnóstico por imagen , Obstrucción del Cuello de la Vejiga Urinaria/etiología
14.
Arch Ital Urol Androl ; 74(1): 16-20, 2002 Mar.
Artículo en Italiano | MEDLINE | ID: mdl-12053443

RESUMEN

Surgery of gynecologic area and of pelvic cavity in general is a risk situation for ureteral injury. The incidence of these injuries is about 1% and may be considered as "unavoidable", irrespective of the surgical approach which could be either abdominal, vaginal or laparoscopic. In this study, 37 patients who had undergone a previous gynecological surgery were assessed for 38 ureteral units. Ureteral injury was identified at the surgical table in 2 patients who were treated successfully during the same surgical session with an end-to-end anastomosis. In 8 patients, a double-J ureteral stent was placed and the cure was obtained in 7 patients. The single case of failure was converted to surgery. 22 female patients for 23 ureteral units were subjected to open surgery performing 16 ureterocystoneostomies, 6 of them with a combined psoas-bladder hitching. In 1 patient a termino-terminal anastomosis was performed due to an injury in an upper site. Finally, in 3 patients nephrectomy was carried out due to a nonfunctional kidney; 1 patient refused surgery, whereas in another patient a spontaneous canalization of the excretory tract was obtained after reposition of a percutaneous nephrostomy. The minimum follow-up is of at least 1 year. The diagnostic aspects and therapeutic indications are then described with a special emphasis on the so-called prognostic factors which could influence the outcome of the treatment. Finally, the main surgical correction techniques employed in case of leakage of ureteral substance, are reviewed.


Asunto(s)
Procedimientos Quirúrgicos Ginecológicos , Complicaciones Intraoperatorias/cirugía , Uréter/lesiones , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Complicaciones Intraoperatorias/diagnóstico por imagen , Persona de Mediana Edad , Nefrectomía , Estudios Retrospectivos , Stents , Resultado del Tratamiento , Uréter/diagnóstico por imagen , Derivación Urinaria , Fístula Urinaria/etiología , Urografía
15.
J Am Chem Soc ; 124(19): 5315-24, 2002 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-11996572

RESUMEN

Axial iron ligation and protein encapsulation of the heme cofactor have been investigated as effectors of the reduction potential (E degrees ') of cytochrome c through direct electrochemistry experiments. Our approach was that of partitioning the E degrees ' changes resulting from binding of imidazole, 2-methyl-imidazole, ammonia, and azide to both cytochrome c and microperoxidase-11 (MP11), into the enthalpic and entropic contributions. N-Acetylmethionine binding to MP11 was also investigated. These ligands replace Met80 and a water molecule axially coordinated to the heme iron in cytochrome c and MP11, respectively. This factorization was achieved through variable temperature E degrees ' measurements. In this way, we have found that (i) the decrease in E degrees ' of cytochrome c due to Met80 substitution by a nitrogen-donor ligand is almost totally enthalpic in origin, as a result of the stronger electron donor properties of the exogenous ligand which selectively stabilize the ferric state; (ii) on the contrary, the binding of the same ligands and N-acetylmethionine to MP11 results in an enthalpic stabilization of the reduced state, whereas the entropic effect invariably decreases E degrees ' (the former effect prevails for the methionine ligand and the latter for the nitrogenous ligands). A comparison of the reduction thermodynamics of cytochrome c and the MP11 adducts offers insight on the effect of changing axial heme ligation and heme insertion into the folded polypeptide chain. Principally, we have found that the overall E degrees ' increase of approximately 400 mV, comparing MP11 and native cytochrome c, consists of two opposite enthalpic and entropic terms of approximately +680 and -280 mV, respectively. The enthalpic term includes contributions from both axial methionine binding (+300 mV) and protein encapsulation of the heme (+380 mV), whereas the entropic term is almost entirely manifest at the stage of axial ligand binding. Both terms are dominated by the effects of water exclusion from the heme environment.


Asunto(s)
Grupo Citocromo c/química , Amoníaco/química , Amoníaco/metabolismo , Animales , Grupo Citocromo c/metabolismo , Electroquímica , Caballos , Imidazoles/química , Imidazoles/metabolismo , Oxidación-Reducción , Peroxidasas/química , Peroxidasas/metabolismo , Temperatura , Termodinámica
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