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1.
Artículo en Inglés | MEDLINE | ID: mdl-38207160

RESUMEN

OBJECTIVE: Laparotomy-assisted fetoscopic closure of spina bifida utilizing heated-humidified carbon dioxide gas has been associated with less maternal morbidity than open in-utero spina bifida closure. Fetal cardiovascular changes during these surgical interventions are not well defined. Our objective was to compare fetal bradycardia (defined as fetal heart rate (FHR)<110 bpm over 10 minutes) and changes in umbilical artery Doppler parameters throughout open in-utero closure with those observed during laparotomy-assisted fetoscopic closure. METHODS: We conducted a prospective cohort study of 22 open and 46 fetoscopic consecutive in-utero closures between 2019 and 2023. Both cohorts had similar preoperative counseling and clinical management. FHR and umbilical artery velocimetry were systematically obtained during preoperative assessment, every 5 minutes during the intraoperative period, and in the postoperative assessment. FHR, pulsatility indexes and end-diastolic flows were segmented into hourly periods during surgery, and the lowest values were averaged for analysis. Umbilical vein maximum velocities were measured in the fetoscopic cohort. Each fetal heart rate recording time point was correlated to maternal parameters, including heart rate, systolic and diastolic blood pressures. RESULTS: Fetal bradycardia occurred in 4/22 cases (18.2%) of open in-utero closure and in 21/46 cases (45.7%) of fetoscopic closure. FHR gradually decreased in both cohorts after general anesthesia and decreased further during surgery. FHR were significantly lower after two hours of surgery in the fetoscopic closure than in the open in-utero closure group. In addition, the FHR (BPM) change in the final stages of the fetal surgery from the baseline FHR was significantly lower in the fetoscopic cohort (-32.3 (-35.7, -29.1)) compared to the open cohort (-23.5 (-28.1, -18.8)) (p=0.002). Abnormal end-diastolic flow (defined as absent or reversed end-diastolic flow) in the umbilical artery Doppler velocity occurred in 3/22 (13.6%) of the open closure cohort and in 23/46 (50%) of the fetoscopic closure cohort (p=0.004). There were no differences in umbilical artery end-diastolic flow and pulsatility index between closure techniques during the various stages of assessment. CONCLUSIONS: We observed a decrease in the FHR and abnormalities in umbilical artery Doppler parameters in both open in-utero and fetoscopic closure groups. Fetal bradycardia was more prominent during fetoscopic closure following heated-humidified carbon dioxide insufflation, but the FHR recovered after cessation of the heated-humidified carbon dioxide. Changes in FHR and umbilical artery Doppler parameters during in-utero spina bifida closure were observed to be transient, no cases required emergency delivery and no fetoscopic closure were converted to open closure. These observations should inform algorithms for perioperative management of fetal bradycardia associated with in-utero spina bifida closure. This article is protected by copyright. All rights reserved.

2.
Ultrasound Obstet Gynecol ; 60(5): 666-672, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-35751885

RESUMEN

OBJECTIVE: During in-utero spina bifida (SB) repair, closure of large defects is often challenging, requiring tissue graft for watertight skin closure. No prior studies have compared primary skin closure vs patch-based repair. Our objective was to compare neonatal and 1-year outcomes associated with these two types of skin closure for in-utero SB repair. METHODS: This was a prospective cohort study of 102 patients undergoing open prenatal SB repair from September 2011 to August 2021 at a single institution. All patients met the inclusion criteria of the Management of Myelomeningocele Study (MOMS), and the surgical procedure for in-utero SB repair was similar to that described in the MOMS trial. During the surgery, if primary skin approximation was not feasible due to the large size of the defect, the decision was at the discretion of the pediatric neurosurgeon to utilize a patch for closure. Neonatal outcomes at birth and 1-year outcomes were compared between the primary skin and patch-based closure groups. RESULTS: Of 102 patients included in the study, 70 (68.6%) underwent primary skin closure and 32 (31.4%) patch-based closure. The patch type included acellular bovine skin matrix (Durepair®; n = 31) and human acellular dermal matrix (Alloderm®; n = 1). Fetuses with myeloschisis were more likely to require patch-based repair than those with myelomeningocele. The median time of fetal repair was 4 min longer for patch-based compared with primary skin closure (37 vs 33 min; P = 0.001). Following patch-based repair, neonates had a longer length of stay in the neonatal intensive care unit (NICU) by 24 days (adjusted risk ratio, 2.40 (95% CI, 1.41-4.29)) compared to those that underwent primary skin closure. There was no difference between the two groups in the other neonatal outcomes, including the need for ventriculoperitoneal shunt placement and cerebrospinal fluid leakage. Outcome at 1 year of age was available for 90 infants. Need for wound revision within their first year after birth was more common in infants who underwent patch-based vs those with primary skin closure (19.4% vs 5.1%; P = 0.05). There was no difference between the two groups in other 1-year outcomes, including the need for ventriculoperitoneal shunt placement by 1 year of age and surgery for tethered cord. CONCLUSIONS: Patch-based closure during SB repair is often needed in fetuses with myeloschisis and is associated with prolonged fetal surgery time, long NICU stay and need for wound revision within the first year after birth. Further studies are required to identify optimal patches for SB repair or alternative methods to improve outcome. © 2022 International Society of Ultrasound in Obstetrics and Gynecology.


Asunto(s)
Meningomielocele , Espina Bífida Quística , Embarazo , Lactante , Femenino , Humanos , Animales , Bovinos , Niño , Meningomielocele/cirugía , Estudios Prospectivos , Edad Gestacional , Derivación Ventriculoperitoneal , Espina Bífida Quística/cirugía
3.
Mol Immunol ; 132: 142-149, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33588245

RESUMEN

Epithelial cells and macrophages represent two major cell populations in the lung. They reside in physical proximity and are influenced by inhaled substances, microbial- and host-derived factors, as well as by crosstalk between each other. Here, we report the first systematic study to compare the effects of apical and basolateral secretomes from primary human small airway epithelial cells (SAEC) on human macrophages. We exposed monocyte-derived macrophages (MDMs) to the secretome supernatants (SN) from the apical and basolateral chamber of SAEC culture in an air-liquid interface (ALI) setting and analyzed expression of macrophage surface markers. We found that the apical SN increased the expression of CD11c and CD16, whereas basolateral SN increased the expression of CD163 and CD300e, consistent with apical and basolateral epithelial secretions inducing an M1-biased and M2-biased macrophage polarization, respectively. Conversely, in the presence of Nontypeable Haemophilus influenzae (NTHi), apical SN from NTHi-exposed SAEC induced CD36, CD163 and CD300e and supressed CD11c expression suggesting a switch towards an M2-biased macrophage polarization. Analysis of SN from polarized epithelium revealed a number of factors with differential expression in the apical and basolateral secretome. Functional neutralization of IL6, IL8 or IL1α in the apical secretome led to a decrease in expression of 'M2-like' surface markers, supporting the concept of epithelial-derived secreted factors influencing macrophage phenotype. In conclusion, we show, for the first time to our knowledge, that SN from polarized epithelium, depending on the side of secretion, apical or basolateral, can elicit a differential influence on the macrophages polarization phenotype.


Asunto(s)
Citocinas/metabolismo , Epitelio/metabolismo , Pulmón/metabolismo , Antígenos CD/metabolismo , Biomarcadores/metabolismo , Células Cultivadas , Células Epiteliales/metabolismo , Humanos , Activación de Macrófagos/fisiología , Macrófagos/metabolismo , Fenotipo
4.
Am J Physiol Lung Cell Mol Physiol ; 319(6): L957-L967, 2020 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-32996783

RESUMEN

Electronic nicotine delivery systems, or e-cigarettes, utilize a liquid solution that normally contains propylene glycol (PG) and vegetable glycerin (VG) to generate vapor and act as a carrier for nicotine and flavorings. Evidence indicated these "carriers" reduced growth and survival of epithelial cells including those of the airway. We hypothesized that 3% PG or PG mixed with VG (3% PG/VG, 55:45) inhibited glucose uptake in human airway epithelial cells as a first step to reducing airway cell survival. Exposure of H441 or human bronchiolar epithelial cells (HBECs) to PG and PG/VG (30-60 min) inhibited glucose uptake and mitochondrial ATP synthesis. PG/VG inhibited glycolysis. PG/VG and mannitol reduced cell volume and height of air-liquid interface cultures. Mannitol, but not PG/VG, increased phosphorylation of p38 MAPK. PG/VG reduced transepithelial electrical resistance, which was associated with increased transepithelial solute permeability. PG/VG decreased fluorescence recovery after photobleaching of green fluorescent protein-linked glucose transporters GLUT1 and GLUT10, indicating that glucose transport function was compromised. Puffing PG/VG vapor onto the apical surface of primary HBECs for 10 min to mimic the effect of e-cigarette smoking also reduced glucose transport. In conclusion, short-term exposure to PG/VG, key components of e-cigarettes, decreased glucose transport and metabolism in airway cells. We propose that this was a result of PG/VG reduced cell volume and membrane fluidity, with further consequences on epithelial barrier function. Taking these results together, we suggest these factors contribute to reduced defensive properties of the epithelium. We propose that repeated/chronic exposure to these agents are likely to contribute to airway damage in e-cigarette users.


Asunto(s)
Sistemas Electrónicos de Liberación de Nicotina , Células Epiteliales/efectos de los fármacos , Glucosa/metabolismo , Sistema Respiratorio/efectos de los fármacos , Transporte Biológico/efectos de los fármacos , Transporte Biológico/fisiología , Glicerol/farmacología , Humanos , Propilenglicol/farmacología
5.
Cell Death Differ ; 23(4): 723-32, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26542461

RESUMEN

Caspases are the executioners of apoptosis. Although much is known about their physiological roles and structures, detailed analyses of missense mutations of caspases are lacking. As mutations within caspases are identified in various human diseases, the study of caspase mutants will help to elucidate how caspases interact with other components of the apoptosis pathway and how they may contribute to disease. DrICE is the major effector caspase in Drosophila required for developmental and stress-induced cell death. Here, we report the isolation and characterization of six de novo drICE mutants, all of which carry point mutations affecting amino acids conserved among caspases in various species. These six mutants behave as recessive loss-of-function mutants in a homozygous condition. Surprisingly, however, two of the newly isolated drICE alleles are gain-of-function mutants in a heterozygous condition, although they are loss-of-function mutants homozygously. Interestingly, they only behave as gain-of-function mutants in the presence of an apoptotic signal. These two alleles carry missense mutations affecting conserved amino acids in close proximity to the catalytic cysteine residue. This is the first time that viable gain-of-function alleles of caspases are described in any intact organism and provides a significant exception to the expectation that mutations of conserved amino acids always abolish the pro-apoptotic activity of caspases. We discuss models about how these mutations cause the gain-of-function character of these alleles.


Asunto(s)
Alelos , Apoptosis/genética , Caspasas/genética , Proteínas de Drosophila/genética , Modelos Genéticos , Mutación Puntual , Animales , Caspasas/metabolismo , Proteínas de Drosophila/metabolismo , Drosophila melanogaster , Humanos
6.
Laryngoscope ; 113(11): 1973-6, 2003 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-14603058

RESUMEN

OBJECTIVES/HYPOTHESIS: The objective was to reveal the location of the neuromuscular junctions in a three-dimensional reconstruction of the human thyroarytenoid muscle within the true vocal fold. STUDY DESIGN: Immunohistochemical analysis of serially sectioned human true vocal folds was performed, followed by reconstruction in three dimensions using computer imaging software. METHODS: Six fresh human larynges from autopsy were harvested, fixed in formalin, and embedded in paraffin. Eight vocal cords were studied from these six larynges. Five-micron serial sections were collected throughout the entire vocal cord in an axial plane at 500-microm intervals. Immunohistochemical analysis was performed with anti-synaptophysin antibody. A computer-controlled imaging and reconstruction system was used to create a three-dimensional reconstruction from the serial sections and to represent the location of the clustered band of neuromuscular junctions within each true vocal fold. The vocal cord was divided into equal thirds from anterior to posterior for statistical analysis. RESULTS: The most neuromuscular junctions (74%) were located in the middle third, and the least (7%) were found in the anterior third. The difference in anterior-to-posterior distribution was statistically significant in all eight specimens by chi2 analysis (P <.001). CONCLUSION: The distribution of neuromuscular junctions is not random within the human thyroarytenoid muscle. Because neuromuscular junctions are most highly concentrated in a band within the mid belly of the muscle, botulinum toxin type A (Botox) injection in patients with spasmodic dysphonia should be targeted to this region.


Asunto(s)
Imagenología Tridimensional/métodos , Músculos Laríngeos/patología , Adulto , Anciano , Toxinas Botulínicas Tipo A/farmacología , Toxinas Botulínicas Tipo A/uso terapéutico , Técnicas de Cultivo , Femenino , Humanos , Inmunohistoquímica , Inyecciones Intramusculares , Músculos Laríngeos/efectos de los fármacos , Músculos Laríngeos/metabolismo , Masculino , Persona de Mediana Edad , Fármacos Neuromusculares/farmacología , Fármacos Neuromusculares/uso terapéutico , Unión Neuromuscular/metabolismo , Unión Neuromuscular/patología , Sinaptofisina/metabolismo , Trastornos de la Voz/tratamiento farmacológico , Trastornos de la Voz/metabolismo , Trastornos de la Voz/patología
9.
Head Neck ; 17(5): 409-13, 1995.
Artículo en Inglés | MEDLINE | ID: mdl-8522442

RESUMEN

BACKGROUND: Squamous cell carcinoma of the low cervical area may be secondary to stomal recurrence following laryngectomy, low cervical esophageal disease, or peritracheal metastasis. Most often patients with disease in this area have already received both surgery and radiotherapy. Prior to Sisson's description of the trans-sternal radical neck dissection or mediastinal dissection the management and prognosis was uniformly poor. Since then, a number of authors have reported their experience with mediastinal dissection. Survival remains poor but palliation has been acceptable. Unfortunately, resectability of the disease cannot often be determined prior to the actual surgical procedure. A number of patients are explored only to have the procedure terminated. Thoracoscopy is a procedure that involves insertion of two or three trocars into the right thoracic cavity with collapse of the right lung. A form of endoscopic surgery, it permits visualization and dissection of the important structures of the mediastinum. Tracheal, esophageal, and great vessel invasion by tumor can be evaluated. METHODS: Prospectively, all patients initially seen with stomal recurrence from 1991 to 1994 were evaluated. CT scans, MRIs as well as thoracoscopy were performed when indicated. RESULTS: One patient required conversion to a minithoracotomy involving a 7-cm chest incision. The patient was found to have unresectable disease with tumor involving the great vessels of the mediastinum. A second patient was found to have unresectable disease with tumor encasing the subclavian artery. The third patient was found to have no mediastinum involvement. The patient with no mediastinum involvement underwent a stomal resection with mediastinal dissection. Reconstruction with a pectoralis major myogenous flap was performed. The patient has remained disease free to date. The remaining two patients were judged to have unresectable disease and were offered palliative treatment. Both of these patients died of the disease within 6 months. CONCLUSIONS: Thoracoscopy provides important information in judging the surgical resectability of patients with stomal recurrence. This procedure has not been previously described in the otolaryngologic literature. We provide some suggestions for its use in the evaluation of the mediastinal extent of disease.


Asunto(s)
Carcinoma de Células Escamosas/patología , Neoplasias Laríngeas/patología , Recurrencia Local de Neoplasia/patología , Estomía , Toracoscopía , Anciano , Carcinoma de Células Escamosas/cirugía , Femenino , Humanos , Neoplasias Laríngeas/cirugía , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia/mortalidad , Recurrencia Local de Neoplasia/cirugía , Estadificación de Neoplasias , Pronóstico , Toracoscopía/métodos , Tomografía Computarizada por Rayos X
10.
Am J Surg ; 170(2): 227-30, 1995 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-7631937

RESUMEN

BACKGROUND: Abdominal aortic aneurysm and renal neoplasm are occasionally discovered concurrently. Simultaneous operative therapy may be an effective alternate management strategy to a staged procedure. PATIENTS AND METHODS: The medical records of 10 consecutive patients undergoing abdominal aortic aneurysm repair and nephrectomy for renal neoplasm were reviewed. Data collected included mode of presentation, preoperative evaluation, renal pathology, and in-hospital morbidity and mortality. Long-term follow-up was obtained through office records and telephone contact. RESULTS: In 7 patients, the renal mass was identified during evaluation of abdominal aortic aneurysm. The aneurysm was identified during evaluation of hematuria in 2 patients. One patient was discovered to have both conditions simultaneously. All patients underwent successful aneurysm repair and nephrectomy. Pathology revealed 6 renal cell carcinomas, 2 complex cysts, 1 hemangiopericytoma, and 1 oncocytoma. Four patients have died in the follow-up period: 1 of metastatic cancer and 3 of unrelated causes. There have been no cases of graft infection. CONCLUSION: Simultaneous abdominal aortic aneurysm repair and nephrectomy for neoplasm is an appropriate management strategy for selected patients.


Asunto(s)
Aneurisma de la Aorta Abdominal/cirugía , Neoplasias Renales/cirugía , Nefrectomía , Adenoma Oxifílico/cirugía , Anciano , Anciano de 80 o más Años , Carcinoma de Células Renales/cirugía , Femenino , Estudios de Seguimiento , Hemangiopericitoma/cirugía , Humanos , Enfermedades Renales Quísticas/cirugía , Masculino , Persona de Mediana Edad
11.
J Urol ; 152(6 Pt 2): 2312-5, 1994 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-7966730

RESUMEN

We describe our experience with a technique for simultaneous urinary and fecal diversion using a single abdominal stoma. The procedure requires the construction of a diverting loop colostomy with division of the colon approximately 15 cm. distal to the stoma. This distal segment of colon acts as a urinary conduit, and allows internal separation of the urine and fecal streams. The procedure has been used in patients without a prior stoma as well as those with existing loop and end colostomies. Unlike the watery diarrhea associated with the wet colostomy described previously, these patients experience a continuous urine output and intermittent semiformed bowel movements. Complications have been minimal: there have been no episodes of clinical pyelonephritis, no new electrolyte problems and no significant stomal complications. In 1 patient late radiographic evidence of hydronephrosis developed associated with advancing metastatic disease, while in another late bilateral ureterocolonic strictures developed. The majority of patients died of the underlying cancer but 1 died of a myocardial infarction 2 weeks postoperatively. This procedure has now been performed in 11 patients with followup from 0.5 to 80 months. The results are gratifying for a group of highly complex cases.


Asunto(s)
Colostomía/métodos , Derivación Urinaria/métodos , Cistitis/cirugía , Neoplasias Endometriales/cirugía , Femenino , Estudios de Seguimiento , Humanos , Masculino , Exenteración Pélvica , Neoplasias de la Próstata/cirugía , Traumatismos por Radiación/cirugía , Neoplasias del Recto/cirugía , Factores de Tiempo , Neoplasias de la Vejiga Urinaria/cirugía
12.
South Med J ; 86(11): 1283-5, 1993 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-8235788

RESUMEN

We have reported the unusual case of a 7-year-old boy who was admitted with respiratory symptoms of several months' duration. He was found to have a tumor of the trachea, which proved to be a low-grade fibrosarcoma with smooth muscle differentiation.


Asunto(s)
Neoplasias de los Bronquios , Fibrosarcoma , Neoplasias Pulmonares , Tráquea , Neoplasias de los Bronquios/patología , Niño , Fibrosarcoma/patología , Humanos , Neoplasias Pulmonares/patología , Masculino , Músculo Liso/patología , Neoplasias de Tejido Muscular/patología , Tráquea/patología
13.
Urology ; 41(6): 582-4, 1993 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-8516998

RESUMEN

Patients with clear cell adenocarcinoma of the kidney often present with metastatic disease, in some cases involving organs in which primary clear cell tumors occur. Under these circumstances, diagnosis of the renal primary tumor may be delayed. Herein we present a case of renal cell carcinoma metastatic to the ovaries initially treated as primary ovarian disease, until the appearance of other metastases prompted the discovery of its true origin. A high index of suspicion and the histologic characteristics of these tumors may allow earlier diagnosis and treatment of a renal primary tumor.


Asunto(s)
Adenocarcinoma/secundario , Neoplasias Renales/patología , Neoplasias Ováricas/secundario , Adenocarcinoma/diagnóstico , Diagnóstico Diferencial , Femenino , Humanos , Neoplasias Renales/diagnóstico , Persona de Mediana Edad , Neoplasias Primarias Desconocidas/diagnóstico , Neoplasias Ováricas/diagnóstico
14.
Arch Dis Child ; 67(4): 530-1, 1992 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-1580688

RESUMEN

Two hundred and sixty one of 279 (93.5%) children known to be tuberculin positive shortly after receiving their neonatal BCG vaccination were still tuberculin positive at age 4 years. The results confirm the continuing effectiveness of neonatal BCG at 4 years.


Asunto(s)
Vacuna BCG/inmunología , Tuberculosis/prevención & control , Preescolar , Humanos , Lactante , Recién Nacido , Factores de Tiempo , Prueba de Tuberculina
15.
Prostate ; 20(1): 51-8, 1992.
Artículo en Inglés | MEDLINE | ID: mdl-1736277

RESUMEN

Prolactin and testosterone are synergistic in stimulating growth of the rat prostate. The lateral lobe is more sensitive to this synergism than the ventral and dorsal lobes. To investigate whether prolactin acts directly in the rat prostate or indirectly through another systemic mediator, anterior pituitary grafts (1 mm3) were implanted in the lateral prostate of castrated Sprague-Dawley rats in whom a 0.5 cm or 1.0 cm testosterone-filled silastic tubing was implanted subcutaneously at the same time. Rats were randomly assigned to receive either the pituitary or a muscle chip of similar size grafted beneath the fascia lateral to the lateral prostate. Twenty-one days later, serum prolactin levels were not elevated in pituitary-grafted animals and were not significantly different from those in muscle-grafted rats. The mean lateral prostate weight on the grafted side in pituitary-implanted rats with 1.0 cm testosterone tubing was 43% heavier than either that of the contralateral side or the corresponding weights in muscle-implanted rats. In pituitary-implanted rats with 0.5 cm testosterone tubing, the mean lateral prostate weight on the grafted side was 60% heavier than either that of the contralateral side or that of the corresponding weights in muscle-implanted rats. The weight of the ventral and dorsal lobes of the prostate was not significantly affected by the presence of pituitary grafts in one of the lateral lobes. The local effect of prolactin on the lateral prostate was further demonstrated by an overall decline in tissue concentrations of dihydrotestosterone in the grafted side. These results provided evidence to indicate that there was a direct effect of prolactin on growth of the lateral prostate in rats.


Asunto(s)
Adenohipófisis/fisiología , Próstata/anatomía & histología , Animales , División Celular , Dihidrotestosterona/análisis , Masculino , Orquiectomía , Tamaño de los Órganos , Hipófisis/trasplante , Adenohipófisis/química , Próstata/química , Ratas , Ratas Endogámicas , Testosterona/administración & dosificación , Testosterona/farmacología
16.
Biochem J ; 266(3): 863-8, 1990 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-2158302

RESUMEN

The effects of potential serum inhibitors upon the growth of calcium hydroxyapatite (HAP) crystals were studied in vivo using a pH-stat system. Whole serum caused a marked decrease in crystal growth in a dose-dependent manner. At a protein concentration of 13 micrograms/ml, whole serum reduced the initial rate of crystal growth from 84 mumol of KOH/h to 48 mumol of KOH/h. Serum components were separated by ultrafiltration (10,000 Da cut-off). The high-molecular-mass fraction containing serum proteins gave an initial rate of crystal growth of 48 mumol of KOH/h compared with 64 mumol of KOH/h given by the low-molecular-mass components. Thus, two-thirds of the inhibitory activity was associated with proteins and other serum macromolecules, whilst the remainder of the activity was associated with the low-molecular-mass components. Albumin-depleted serum showed an initial rate of crystal growth of 59 mumol of KOH/h, whilst albumin purified by affinity chromatography gave an initial rate of crystal growth of 56 mumol of KOH/h at the same protein concentration. Albumin, therefore, not only accounts for half of the protein concentration in serum, but also contributes half of the inhibitory activity of the high-molecular-mass fraction. Heat denaturation of albumin dramatically enhanced the inhibition of HAP seeded growth with the initial rate of crystal growth falling to 27 mumol of KOH/h after treatment compared with 62 mumol of KOH/h before denaturation. Isoelectric focusing indicated that the tertiary and secondary structure, and hence the distribution of surface charge of albumin, are altered by heat denaturation. Gels showed a mixture of species with isoelectric points ranging from 6.0 to 5.0 compared with the native protein value of 4.7. These data suggest that adsorption of serum proteins to the growing HAP crystals is one mechanism of growth inhibition. It is also clear that the most abundant serum protein, albumin, is an important mediator of this process.


Asunto(s)
Sangre , Hidroxiapatitas , Albúmina Sérica/farmacología , Fenómenos Químicos , Química , Cristalización , Diálisis , Durapatita , Calor , Humanos , Técnicas In Vitro , Desnaturalización Proteica
18.
J Urol ; 141(5): 1189-91, 1989 May.
Artículo en Inglés | MEDLINE | ID: mdl-2709507

RESUMEN

A new technique to achieve simultaneous diversion of the urinary and fecal streams using a single abdominal stoma is described. The procedure consists of the construction of a diverting loop colostomy with division of the colon approximately 10 to 15 cm. distal to the stoma. The segment of colon distal to the stoma, the urine limb, acts as a urinary conduit. To date 3 patients have undergone the procedure with followup of 3, 13 and 18 months. Neither upper tract infection nor upper tract deterioration has occurred. The potential role of this procedure to treat a difficult group of patients is discussed.


Asunto(s)
Colostomía/métodos , Derivación Urinaria/métodos , Anciano , Colectomía , Femenino , Estudios de Seguimiento , Humanos , Persona de Mediana Edad , Exenteración Pélvica , Neoplasias Pélvicas/cirugía , Traumatismos por Radiación/cirugía , Factores de Tiempo
19.
Urol Radiol ; 11(3): 186-9, 1989.
Artículo en Inglés | MEDLINE | ID: mdl-2688256

RESUMEN

We report on the sonographic (US) and magnetic resonance imaging (MRI) appearance of a mixed sex-cord stromal tumor of the testis. The case is notable due to its rarity, its unusual imaging characteristics as correlated with pathology, and the ability of MRI, in this particular case, to give more complete information than US as to the character of the lesion.


Asunto(s)
Imagen por Resonancia Magnética , Neoplasias Testiculares/diagnóstico , Testículo/patología , Ultrasonografía , Adulto , Humanos , Masculino
20.
J Urol ; 141(1): 126-7, 1989 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-2642309

RESUMEN

We report a case of a granulosa cell tumor of the testis. The ultrastructural characteristics of this rare tumor were compared to its homologue in the ovary and they were similar.


Asunto(s)
Tumor de Células de la Granulosa/ultraestructura , Neoplasias Testiculares/ultraestructura , Testículo/ultraestructura , Ultrasonografía , Adulto , Tumor de Células de la Granulosa/diagnóstico , Humanos , Masculino , Neoplasias Testiculares/diagnóstico
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