RESUMEN
The review article "Operative Techniques and Outcomes in Metabolic Surgery: Sleeve Gastrectomy" by Hüttl et al. is concerned with laparoscopic sleeve stomach operations ("sleeve gastrectomy") for the surgical treatment of morbid obesity (Zentralblatt für Chirurgie 2009; 134: 24-31). After an analysis of the available literature and own results, the authors concluded that the laparoscopic sleeve operation is established today as an effective standard procedure in the therapy for obesity.We would like to comment on the content of this article.
Asunto(s)
Gastrectomía/métodos , Laparoscopía/métodos , Obesidad Mórbida/cirugía , Estudios de Seguimiento , Ghrelina/sangre , Humanos , Complicaciones Posoperatorias/sangre , Complicaciones Posoperatorias/etiología , Resultado del Tratamiento , Pérdida de Peso/fisiologíaRESUMEN
BACKGROUND: The development of therapeutic strategies for treatment of metastasized colorectal carcinoma requires biologically relevant and adequate animal models generating both metastases and the dissemination of tumor cells. METHODS: To prove the efficiency of orthotopic implantation concerning induction of minimal residual disease (MRD) colorectal cancer tissue from 10 patients was transplanted orthotopically into nude mice. In the intraportal injection model 1 x 10(6) HT-29 human colon cancer cells were injected. We investigated by histological studies and CK-20 RT-PCR the occurrence of hematogenous metastases and the dissemination of human colon cancer cells in bone marrow. RESULTS: Following orthotopic implantation of human colon cancer tissue the lymph node and hepatic metastasis rates were low. MRD as reflected by CK-20 positivity of the bone marrow was present in 22.2%. The intraportal injection of 1 x 10(6) HT-29 human colon cancer cells produced hepatic metastases in up to 89% of all animals. The intraportal injection of 1 x 10(6) cells also generated MRD in the bone marrow in 63% of animals. CONCLUSIONS: The intraportal injection model represents a biologically relevant and adequate animal model for the induction of both reproducible hepatic metastasis and MRD in the bone marrow. In this regard it seems to be superior to the orthotopic implantation model.
Asunto(s)
Neoplasias del Colon/patología , Animales , Línea Celular Tumoral , Neoplasias del Colon/genética , Neoplasias del Colon/secundario , Neoplasias Colorrectales/genética , Neoplasias Colorrectales/patología , Neoplasias Colorrectales/secundario , Modelos Animales de Enfermedad , Femenino , Células HT29 , Humanos , Inyecciones Intravenosas , Queratina-20/genética , Neoplasias Hepáticas Experimentales/secundario , Metástasis Linfática , Ratones , Ratones Desnudos , Trasplante de Neoplasias/métodos , Células Neoplásicas Circulantes , Vena Porta , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Trasplante HeterólogoRESUMEN
We describe the case of a 54-year-old man with a tumour of the proximal esophagus (cT3-4,N1,M0), who underwent percutaneous endoscopic gastrostomy (PEG) for enteral feeding. Primary radiochemotherapy was initiated shortly after PEG insertion. Five months after PEG insertion the patient detected a nodule at the site. The general practitioner diagnosed this nodule as a brotic reaction. Another six weeks later, ulceration that had grown along the PEG probe at the PEG site was observed on gastroscopy. The primary tumour was not visible. Histological examination showed an abdominal wall metastasis of the esophageal cancer. Despite subtotal gastrectomy with en-bloc resection of the tumour, distant metastasis developed. The patient died six months after surgery. About 47 cases of abdominal wall metastases as late complications at the site have been reported until now. The mechanism of tumour spread of PEG site is a subject of controversial discussion. As direct mechanical tumour implantation is the most likely mechanism, an alternative method like operative (laparoscopic) or radiological PEG placement should be considered in cases with advanced, stenotic tumours.
Asunto(s)
Neoplasias Abdominales/secundario , Carcinoma de Células Escamosas/patología , Carcinoma de Células Escamosas/secundario , Carcinoma de Células Escamosas/cirugía , Nutrición Enteral , Neoplasias Esofágicas/patología , Neoplasias Esofágicas/cirugía , Gastrostomía , Siembra Neoplásica , Neoplasias Cutáneas/patología , Neoplasias Cutáneas/secundario , Neoplasias Gástricas/patología , Neoplasias Gástricas/secundario , Neoplasias Abdominales/patología , Neoplasias Abdominales/cirugía , Pared Abdominal/patología , Pared Abdominal/cirugía , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Carcinoma de Células Escamosas/tratamiento farmacológico , Carcinoma de Células Escamosas/radioterapia , Terapia Combinada , Progresión de la Enfermedad , Neoplasias Esofágicas/tratamiento farmacológico , Neoplasias Esofágicas/radioterapia , Gastrectomía , Derivación Gástrica , Humanos , Hígado/patología , Neoplasias Hepáticas/patología , Neoplasias Hepáticas/secundario , Neoplasias Hepáticas/cirugía , Masculino , Persona de Mediana Edad , Piel/patología , Neoplasias Cutáneas/cirugía , Neoplasias Gástricas/cirugía , Tomografía Computarizada por Rayos XRESUMEN
BACKGROUND: Reflux recurrence is the most common long-term complication following fundoplication. Results for different techniques of laparoscopic antireflux surgery were retrospectively compared after 10 years. METHODS: From 1992 to 1997, the 120 patients studied had laparoscopic fundoplication with 'tailored' approaches: 88 Nissen, 22 anterior, and ten Toupet fundoplications. Follow-up of 87% of these patients included disease-related questions and the gastrointestinal quality of life index (GIQLI). RESULTS: Of the patients, 89% would select surgery again. Regurgitations after fundoplication were noted from 15% of patients after Nissen, 44% after anterior, and 10% after Toupet types (P=0.04). Twenty-eight percent were on acid suppression therapy. Proton pump inhibitors were used less frequently following Nissen fundoplication (P=0.01). The GIQLI score was 110+/-24 without significant differences for type of fundoplication. DISCUSSION: Overall results are satisfactory after 10 years of experience with fundoplication. Total fundoplication appears to control reflux better than partial fundoplication.
Asunto(s)
Fundoplicación/métodos , Reflujo Gastroesofágico/cirugía , Laparoscopía/métodos , Complicaciones Posoperatorias/prevención & control , Anciano , Femenino , Estudios de Seguimiento , Reflujo Gastroesofágico/etiología , Reflujo Gastroesofágico/prevención & control , Humanos , Masculino , Persona de Mediana Edad , Satisfacción del Paciente , Complicaciones Posoperatorias/etiología , Prevención SecundariaRESUMEN
Plasma growth hormone (GH) concentrations were determined every 20 minutes during sleep in 71 prepubertal children: 22 had endogenous major depressive disorder, 20 had nonendogenous major depressive disorder, 21 had nondepressed neurotic disorders, and eight were normal. Both depressive groups secreted significantly more GH during sleep than did controls. Measures included maximal GH plasma peak and area under the curve (AUC) during the total sleep period, during the first three hours after sleep onset, and during the first five hours after sleep onset. An AUC cutoff of 2,000 ng X min/mL identified positively half the prepubertal children with major depression; with a specificity of 78% (v neurotics) and 100% (v normal children). Increased GH secretion during sleep may be a marker of illness, a past episode, or trait for prepubertal major depression regardless of endogenicity.
Asunto(s)
Trastorno Depresivo/diagnóstico , Hormona del Crecimiento/metabolismo , Sueño/fisiología , Síntomas Afectivos/sangre , Síntomas Afectivos/diagnóstico , Síntomas Afectivos/fisiopatología , Niño , Trastorno Depresivo/sangre , Trastorno Depresivo/fisiopatología , Femenino , Hormona del Crecimiento/sangre , Humanos , Masculino , Trastornos Neuróticos/sangre , Trastornos Neuróticos/diagnóstico , Trastornos Neuróticos/fisiopatología , PubertadRESUMEN
BACKGROUND: Patients with gastroesophageal reflux disease who reflux only in the upright position are thought to have a less severe abnormality. Controversy exists over whether these patients should be considered candidates for antireflux surgery. METHODS: A total of 224 consecutive patients with increased esophageal acid exposure on 24-hour pH monitoring were classified as having upright (n = 54), supine (n = 72), or bipositional (n = 98) reflux and were evaluated by manometry and endoscopy. Of these, 116 patients had a laparoscopic Nissen fundoplication. Their clinical outcome at a median of 12 months (range 4 to 44 months) was compared. RESULTS: Patients with upright reflux had a lower prevalence of a structurally defective lower esophageal sphincter, fewer hiatal hernias, and less esophageal injury when compared to those with bipositional reflux (p < 0.005). Excellent (asymptomatic) or good outcome (minor symptoms not requiring acid suppression therapy) was achieved in 86% of the patients with upright reflux, 90% of those with supine reflux, and 89% of those with bipositional reflux. CONCLUSIONS: Patients with upright reflux have less complicated, earlier disease and have results equivalent to those patients with supine and bipositional reflux after antireflux surgery.
Asunto(s)
Procedimientos Quirúrgicos Electivos , Reflujo Gastroesofágico/fisiopatología , Reflujo Gastroesofágico/cirugía , Laparoscopía , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Contraindicaciones , Endoscopía , Unión Esofagogástrica/fisiopatología , Femenino , Cirugía General , Hernia Hiatal/epidemiología , Humanos , Concentración de Iones de Hidrógeno , Masculino , Manometría , Persona de Mediana Edad , Monitoreo Fisiológico , Contracción Muscular , Evaluación de Resultado en la Atención de Salud , Postura , Posición SupinaRESUMEN
BACKGROUND: Cancer of the cardia is now topographically classified into three types: type I, with the tumor center in the distal esophagus treated with subtotal esophagectomy; type II, arising at the gastroesophageal junction and treated with distal esophagectomy and either proximal or total gastrectomy; and type III, subcardial cancer treated with extended total gastrectomy. Our objective was to review the new classifications and compare the outcomes in patients grouped and treated according to these classifications. METHODS: Seventy-four patients with cancer of the cardia--15 with type I, 30 with type II, and 29 with type III cancer--underwent surgical resection at our institution between 1992 and 1997. Postoperative complications, UICC stages, and survival (Kaplan-Meier) were compared. RESULTS: The majority of patients with type I (73%) or type II (53%) cancer had stage I or II tumors, but only 27% of patients with type III cancer had this tumor stage (P < .05). Overall 30-day mortality was 4% and morbidity was 31%. Curative resections were performed in 73% (54 of 74) of the patients with 3-year survival rates of 72% (type I), 68% (type II), and 61% (type III). CONCLUSION: The recommended therapy for the different types of cancer of the cardia results in acceptable morbidity, mortality, and survival rates.
Asunto(s)
Carcinoma/clasificación , Neoplasias Gástricas/clasificación , Adenocarcinoma/clasificación , Adenocarcinoma/mortalidad , Adenocarcinoma/cirugía , Adulto , Anciano , Carcinoma/mortalidad , Carcinoma/cirugía , Cardias , Esofagectomía , Esofagoplastia , Femenino , Gastrectomía , Humanos , Escisión del Ganglio Linfático , Masculino , Persona de Mediana Edad , Neoplasias Gástricas/mortalidad , Neoplasias Gástricas/cirugía , Tasa de SupervivenciaRESUMEN
OBJECTIVE: To examine the factors affecting outcome in patients with advanced gastroesophageal reflux disease. DESIGN: Retrospective analysis. SETTING: University tertiary referral center. PATIENTS: Thirty-seven patients with advanced gastroesophageal reflux disease and no previous antireflux surgery. INTERVENTIONS: Thirty patients underwent Collis gastroplasty for esophageal lengthening and Belsey partial fundoplication. Seven patients with esophageal stricture and global loss of esophageal body motility who underwent primary esophagectomy and reconstruction were used as a comparison group. OUTCOME MEASURES: Symptomatic outcome in all 37 patients was assessed by questionnaire at a median of 25 months (range, 5-156 months) after surgery. In a subset of 11 patients undergoing the Collis-Belsey procedure, outcome was measured using 24-hour pH and results of motility studies. RESULTS: The Collis-Belsey procedure was successful in relieving symptoms of gastroesophageal reflux in 21 (70%) of the 30 patients. The outcome was excellent or good in 16 (89%) of 18 patients who presented with symptoms other than dysphagia, but only in 5 (42%) of 12 patients with dysphagia (P = .01). The outcome was particularly poor if dysphagia was associated with a previously dilated esophageal stricture. Persistent or induced dysphagia was the reason for failure in all but 1 patient. Results of 24-hour esophageal pH studies were returned to normal in 8 (73%) of 11 patients undergoing postoperative evaluation. Contraction amplitudes in the distal esophagus and the prevalence of simultaneous contractions in these segments did not change after the operation. All 7 patients who underwent primary esophagectomy were classified as having an excellent or good outcome and were relieved of their reflux symptoms, including dysphagia. Six of these could eat 3 meals per day and enjoyed an unrestricted diet. CONCLUSIONS: The outcome of the Collis-Belsey procedure in patients with advanced gastroesophageal reflux disease without dysphagia is excellent. It is less so in patients with dysphagia as a preoperative symptom. Esophagectomy can provide a good outcome in patients who have a combination of dysphagia stricture and a profound loss of esophageal motility.
Asunto(s)
Fundoplicación/métodos , Reflujo Gastroesofágico/cirugía , Gastroplastia/métodos , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Reflujo Gastroesofágico/fisiopatología , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Resultado del TratamientoRESUMEN
Duodenogastric reflux has long been associated with various diseases of the foregut. Even though bile is often used as a marker, duodenogastric reflux consists of other components such as pancreatic juice and duodenal secretions. The aim of this study was to investigate the occurrence of duodenogastric reflux, its components, and the variability of its composition in normal subjects. Twenty healthy volunteers (7 men and 13 women) whose median age was 24 years underwent combined 24-hour bilirubin and gastric pH monitoring and intraluminal gastric aspiration. All probes were placed at 5 cm below the lower border of the lower esophageal sphincter. Aspiration was performed hourly and at any time when bilirubin and/or pH monitoring showed signs of duodenogastric reflux. Elastase and amylase were measured in the aspirate. All volunteers had episodes of physiologic duodenogastric reflux. A total of 70 episodes of duodenogastric reflux were registered with a median of three episodes (range 1 to 8) per subject. Most bile reflux occurred separately from pancreatic enzyme reflux. Pancreatic enzyme aspirate was significantly more often associated with a rise in pH in comparison to bile reflux (P <0.01). Duodenogastric reflux is a physiologic event with varying composition. Both bile and pancreatic enzyme reflux frequently occur separately. These findings could explain the disagreement regarding assessment and interpretation of duodenogastric reflux in the past. Thus monitoring of duodenogastric reflux requires more than the detection of just one component.
Asunto(s)
Reflujo Duodenogástrico/metabolismo , Adulto , Amilasas/análisis , Bilis/química , Bilirrubina/química , Reflujo Duodenogástrico/enzimología , Reflujo Duodenogástrico/fisiopatología , Duodeno/metabolismo , Femenino , Contenido Digestivo/química , Humanos , Concentración de Iones de Hidrógeno , Secreciones Intestinales/química , Intubación Gastrointestinal/instrumentación , Lipasa/análisis , Masculino , Monitoreo Ambulatorio/instrumentación , Elastasa Pancreática/análisis , Jugo Pancreático/química , Pancreatina/análisis , Estadística como Asunto , Estómago/fisiopatologíaRESUMEN
In a prospective study of 188 patients with morbid obesity, the time-dependent changes in the quality of life of individual patients were analyzed following laparoscopic gastric banding (LGB). These 188 patients (148 females and 40 males; age 19 to 59 years; body mass index 33 to 72 kg/m(2)) underwent evaluation of the LGB according to a strict protocol that included psychological testing using standardized instruments, detailed medical evaluation, upper gastrointestinal function studies, and evaluation of quality of life using the Gastrointestinal Quality of Life Index (GIQLI). Following this evaluation, 73 patients (57 females and 16 males; age 37 years [range 19 to 59 years]; body mass index 48 kg/m(2) [range 37 to 72 kg/m(2)]) underwent LGB and were followed up for 2 years focusing on weight loss, postoperative morbidity, weight-related comorbidity, and quality of life. The results demonstrate that LGB is well able to allow for a significant loss of excess weight and a significant improvement in patients' quality of life, both after a rather short period of time after surgery and at a continuous rate throughout the follow-up. The price for this success that was found in approximately 90% of patients is a complication rate of 38%; 85% of these patients, almost one third of all patients, must undergo some type of revision surgery. However, once the complications are resolved, these patients achieve the same level of weight loss and improvement in quality of life as patients with an uncomplicated postoperative course.
Asunto(s)
Gastroplastia , Laparoscopía , Obesidad Mórbida/psicología , Calidad de Vida , Adulto , Índice de Masa Corporal , Femenino , Estudios de Seguimiento , Estado de Salud , Humanos , Masculino , Persona de Mediana Edad , Obesidad Mórbida/cirugía , Factores de Tiempo , Pérdida de PesoRESUMEN
Columnar-lined epithelium with specialized intestinal metaplasia of the esophagus (i.e., Barrett's esophagus) is a premalignant condition caused by chronic gastroesophageal reflux disease. Progression of intestinal metaplasia may be avoided by antireflux surgery, whereas regeneration of esophageal mucosa could be achieved by endoscopic argon plasma coagulation (EAPC). The aim of this prospective study was to show the early results of a combination of EAPC and antireflux surgery. Thirty patients with Barrett's esophagus were treated between August 1996 and December 1999. Regeneration of esophageal mucosa was achieved with several sessions of EAPC under general anesthesia. All patients were receiving a double dose of proton pump inhibitors. Endoscopic follow-up was performed 6 to 8 weeks after the last session. Antireflux surgery (Nissen [n = 26] or Toupet [n = 4] fundoplication) followed complete regeneration of the squamous epithelium in the esophagus. One year after laparoscopic fundoplication and EAPC follow-up with endoscopy and quadrant biopsies of the esophagus, 24-hour pH monitoring and esophageal manometry were performed. All 30 patients showed complete regeneration of the squamous epithelium after a median of two sessions (range 1 to 7) of EAPC. Twenty-two patients underwent 1-year follow-up studies. All showed endoscopically an intact fundic wrap. Recurrence of a 1 cm segment of Barrett's epithelium without dysplasia was present in two patients, both of whom had recurrent acid reflux due to failure of their antireflux procedure. Our results indicate that the combination of EAPC and antireflux surgery is an effective treatment option in patients with Barrett's esophagus with gastroesophageal reflux disease. Long-term follow-up of this therapy is necessary to evaluate its effect on cancer risk in Barrett's esophagus.
Asunto(s)
Esófago de Barrett/cirugía , Electrocoagulación/métodos , Esofagoscopía/métodos , Fundoplicación/métodos , Reflujo Gastroesofágico/cirugía , Laparoscopía/métodos , Adulto , Anciano , Argón , Esófago de Barrett/etiología , Esófago de Barrett/patología , Biopsia , Terapia Combinada , Progresión de la Enfermedad , Femenino , Reflujo Gastroesofágico/complicaciones , Reflujo Gastroesofágico/diagnóstico , Humanos , Masculino , Persona de Mediana Edad , Proyectos Piloto , Estudios Prospectivos , Recurrencia , Factores de Riesgo , Resultado del TratamientoRESUMEN
Experimental studies have shown that the severity of esophageal mucosal injury in gastroesophageal reflux disease is related to the reflux of both gastric and duodenal juice. The purpose of this study was to determine whether duodenal juice potentiates esophageal injury in patients with reflux disease or, in fact, causes no harm allowing acid and pepsin to do the damage. A total of 148 consecutive patients who had no previous gastric or esophageal surgery underwent endoscopy and biopsy, manometry, and 24-hour esophageal pH and bilirubin monitoring. Esophageal injury was defined by the presence of erosive esophagitis, stricture, or biopsy-proved Barrett's esophagus. Exposure to duodenal juice, identified by the absorbance of bilirubin, was defined as an exposure time exceeding the ninety-fifth percentile measured in 35 volunteers. To separate the effects of gastric and duodenal juice, patients were stratified according to their acid exposure time. One hundred patients had documented acid reflux on pH monitoring, and in 63 of them it was combined with reflux of duodenal juice. Patients with combined reflux (50 of 63) were more likely to have injury than patients without combined reflux (22 of 37; P < 0.05). When the acid exposure time was greater than 10%, patients with injury (n = 40) had a greater exposure to duodenal juice (median exposure time 17.2% vs. 1.1%, P = 0.006) than patients without injury (n = 5), but there was no difference in their acid exposure (16.9% vs. 13.4%). Patients with dysplasia of Barrett's epithelium (n = 9) had a greater exposure to duodenal juice (median exposure time 30.2% vs. 7.2%, P = 0.04) compared to patients without complications (n = 25), whereas acid exposure was the same (16.4% vs. 15%). Duodenal juice adds a noxious component to the refluxed gastric juice and potentiates the injurious effects of gastric juice on the esophageal mucosa.
Asunto(s)
Reflujo Duodenogástrico/complicaciones , Reflujo Gastroesofágico/complicaciones , Reflujo Gastroesofágico/fisiopatología , Adulto , Femenino , Humanos , Masculino , Persona de Mediana EdadRESUMEN
The relative importance of the lower esophageal sphincter (LES) and hiatal hernia in the pathogenesis of gastroesophageal reflux disease is controversial. To identify the role of hiatal hernia and LES in reflux disease, 375 consecutive patients with foregut symptoms and no previous foregut surgery were evaluated. All patients underwent upper endoscopy, stationary manometry, and 24-hour esophageal pH monitoring. Hiatal hernia was diagnosed endoscopically, when the distance between the crural impression and the gastroesophageal junction was >/=2 cm. The LES was considered structurally defective when the resting pressure was =6 mm Hg, the overall length was less than 2 cm, and/or the abdominal length was less than 1 cm. Factors predicting abnormal esophageal acid exposure (composite score >14.7) were analyzed using multivariate analysis. The presence of a hiatal hernia and a defective LES were identified as independent predictors of abnormal esophageal acid exposure. LES pressure and abdominal length were reduced in patients with hiatal hernia by 4 mm Hg and 0.4 cm, irrespective of the presence of gastroesophageal reflux disease. It is concluded that both a structurally defective LES and hiatal hernia are important factors in the pathogenesis of reflux disease. It is hypothesized that in the presence of a structurally normal LES, the altered geometry of the cardia imposed by a hiatal hernia facilitates the ability of gastric wall tension to pull open the sphincter.
Asunto(s)
Enfermedades del Esófago/complicaciones , Unión Esofagogástrica/fisiopatología , Reflujo Gastroesofágico/etiología , Hernia Hiatal/complicaciones , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Cardias/patología , Enfermedades del Esófago/fisiopatología , Unión Esofagogástrica/patología , Esofagoscopía , Esófago/patología , Esófago/fisiopatología , Femenino , Predicción , Ácido Gástrico/fisiología , Reflujo Gastroesofágico/fisiopatología , Hernia Hiatal/patología , Hernia Hiatal/fisiopatología , Humanos , Concentración de Iones de Hidrógeno , Modelos Logísticos , Masculino , Manometría , Persona de Mediana Edad , Monitoreo Ambulatorio , Análisis Multivariante , PresiónRESUMEN
In the rat model, esophageal adenocarcinoma reproducibly develops following surgically induced duodenal reflux into the esophagus and administration of nitrosamine. In addition, decreasing gastric acid via partial or total gastrectomy increases the prevalence of adenocarcinoma in this model. We questioned whether carcinogen was necessary for cancer development in the gastrectomized model and whether esophageal acidification could reverse the effect of gastrectomy. Three groups of 26 rats each were randomized to a surgical procedure to produce one of the following reflux models: gastroduodenal reflux by esophagojejunostomy, duodenal reflux by total gastrectomy and esophagojejunostomy, or no reflux by Roux-en-Y reconstruction. In a second experiment, 42 rats were operated on to induce duodenal reflux. One week following surgery, they were randomized to receive acidified water (pH 1.8) or tap water. The animals were killed at 24 weeks of age, and the esophagus was evaluated histologically. All animals with reflux had severe esophagitis and 87% developed columnar lining of the distal esophagus. Nearly half (48%) developed adenocarcinoma at the anastomotic site 16 weeks postoperatively and without carcinogen administration. Cancer prevalence did not differ between animals with gastroduodenal or duodenal reflux but tended to be lower in animals receiving acidified water. Duodenoesophageal reflux is carcinogenic in the rat model. Exogenous carcinogen is not necessary for cancer development in gastrectomized rats.
Asunto(s)
Adenocarcinoma/etiología , Reflujo Duodenogástrico/fisiopatología , Duodeno/fisiopatología , Neoplasias Esofágicas/etiología , Reflujo Gastroesofágico/fisiopatología , Adenocarcinoma/patología , Animales , Carcinógenos , Reflujo Duodenogástrico/complicaciones , Neoplasias Esofágicas/patología , Esófago/patología , Gastrectomía , Reflujo Gastroesofágico/complicaciones , Masculino , Prevalencia , Distribución Aleatoria , Ratas , Ratas Sprague-DawleyRESUMEN
Gastroeosphageal reflux disease has been associated with long segments of Barrett's esophagus =3 cm), but little is known about its association with shorter segments. The aim of this study was to evaluate anatomic and physiologic alterations of the cardia and esophageal exposure to gastric and duodenal juice in patients with short and long segments of Barrett's esophagus. Furthermore, these patients were compared to each other and to patients with erosive esophagitis and those with no mucosal injury. Two hundred sixty-two consecutive patients with foregut symptoms were divided into the following four groups based on endoscopic and histologic findings: group 1, no mucosal injury; group 2, erosive esophagitis; group 3, short-segment Barrett's esophagus; and group 4, long-segment Barrett's esophagus. Esophageal exposure time to acid and bilirubin, lower esophageal sphincter characteristics, and endoscopic anatomy of the cardia were compared between the groups. Patients with short-segment Barrett's esophagus had elevated esophageal acid and bilirubin exposure, decreased lower esophageal sphincter pressure and length, and a high incidence of hiatal hernia. These abnormalities were similar to those in patients with esophagitis and in general less profound than those found in patients with long-segment Barrett's esophagus. The length of intestinal metaplasia was higher in patients with a defective lower esophageal sphincter. Short-segment Barrett's esophagus is a complication of severe gastroesophageal reflux disease and is associated with the reflux of both gastric and duodenal juice similar to that seen in patients with long-segment Barrett's esophagus.
Asunto(s)
Esófago de Barrett/etiología , Reflujo Gastroesofágico/complicaciones , Adulto , Anciano , Anciano de 80 o más Años , Esófago de Barrett/patología , Esófago de Barrett/fisiopatología , Bilirrubina/análisis , Cardias/patología , Distribución de Chi-Cuadrado , Esofagitis/etiología , Unión Esofagogástrica/fisiopatología , Esofagoscopía , Femenino , Humanos , Concentración de Iones de Hidrógeno , Intestinos/patología , Masculino , Manometría , Metaplasia , Persona de Mediana Edad , Estadísticas no ParamétricasRESUMEN
A simple radioimmunoassay (RIA) for the direct quantitation of plasma dexamethasone (DEX) at the picogram level has been developed. An antiserum with high specificity and avidity was obtained by the immunization of a carefully synthesized dexamethasone-21-succinyl-thyroglobulin with a high incorporation ratio. As little as 1 pg of DEX in 50 microL of plasma sample can be detected directly by this RIA without extraction and other purification procedures. Intra- and interassay coefficients of variation were 2.1 and 3.3% for plasma levels at 2.93 ng/mL or 2.3 and 7.2% for plasma levels at 0.88 ng/mL. Blank values for plasma of normal or pre-DEX patients were always under the detection limit (20 pg/mL). Excellent linearity (r = 0.9991-0.9999) was demonstrated between the serial dilutions of six plasma samples and their corresponding DEX concentrations. In single-dose DEX (0.25-1 mg) pharmacokinetic studies, plasma DEX was consistently detectable up to 24 h post dose. Compared with existing methods, this direct RIA demonstrates superior performance with regard to simplicity, sensitivity, specificity, and reproducibility. It also enables high sample throughput and has proven robust in our hands. This assay should be readily transferable to other laboratories for clinical or research purposes.
Asunto(s)
Dexametasona/sangre , Animales , Fenómenos Químicos , Química Física , Cromatografía Líquida de Alta Presión , Humanos , Indicadores y Reactivos , Conejos , Radioinmunoensayo , Tiroglobulina/análisisRESUMEN
Antisera of high sensitivity and selectivity were obtained from rabbits immunized with conjugates of hemisuccinylated fluphenazine and porcine thyroglobulin. The antiserum selected (titer 1:6000) for the development of the RIA was obtained after a priming dose and a single iv booster injection three months later. This antiserum had negligible crossreactivity with known available metabolites of fluphenazine (FPZ) and an affinity constant of 2 X 10(10) L/mol. Tritiated FPZ was further purified by HPLC and used as a ligand. The method detects as little as 20 pg/mL of plasma (4 pg/RIA tube) after 1 mL of plasma is extracted. The extraction was performed at a basic pH with heptane: isoamyl alcohol (99:1); the solvent was then back extracted using an acetic phosphate buffer. Recoveries were uniformly high (88.6 +/- 2.1%), and this aqueous buffer extract was used directly in the RIA procedure. The assay has intra- and interassay coefficients of variation of 5.8 and 8.2%, respectively, in a plasma concentration of 95 pg/mL. Results using this procedure have been cross validated against an HPLC procedure (r = 0.952, slope = 1.032, intercept = 0.009, n = 18). In a single-dose FPZ study (10 mg, po), plasma FPZ levels in 25 normal volunteers could be monitored greater than 48 h post dose. Single plasma level profiles, after an initial injection of 12.5 mg of FPZ decanoate, could be measured greater than 36 d, and, in some cases, up to 100 d post dose.
Asunto(s)
Flufenazina/sangre , Administración Oral , Cromatografía Líquida de Alta Presión , Flufenazina/farmacocinética , Humanos , Inyecciones Intramusculares , RadioinmunoensayoRESUMEN
The backscattered ultrasonic signal from soft tissue can be considered to consist of two parts: a spatially fluctuating component due to coherent scattering from randomly distributed scattering centers and a relatively constant component related to structural ordering. The relationship between these, which has been termed the "beam ratio parameter" influences the speckle pattern of an ultrasound image. First-order image statistics for this special speckle pattern are characterized by the Rician distribution. Changes of second-order statistics have also been derived as a function of the beam ratio parameter. A new method for the estimation of the beam ratio parameter from the intensity distribution of the ultrasonic signal is described in this paper. This method was used to measure the parameter in ultrasonic images from phantoms and liver tissue yielding values of about 0.1. The measured changes of the second-order statistics were not correlated to this parameter. The results indicate that the relatively constant intensity component related to structural ordering has only a small influence on the speckle pattern.
Asunto(s)
Hígado Graso Alcohólico/diagnóstico por imagen , Cirrosis Hepática Alcohólica/diagnóstico por imagen , Hígado/diagnóstico por imagen , Biopsia , Hígado Graso Alcohólico/patología , Humanos , Hígado/patología , Cirrosis Hepática Alcohólica/patología , Matemática , Localización de Sonidos , UltrasonografíaRESUMEN
Assessment of tissue vascularization with color Doppler (CD) can improve differential diagnosis of tumors. Until now, measurement of flow velocities is restricted to conventional duplex ultrasound of single vessels or semiquantitative scoring of the vessel distribution in CD. We developed a new method for quantification of CD data in organs or tumors by statistical image analysis. Based on standardized image recording, data is acquired from the video output of any ultrasound scanner using a 24-bit color framegrabber in a personal computer. The digitized colors are recognized according to their position in the CD palette bar resulting in an 8-bit color image (number of identified pixels > 99.9%). Within the region of interest, statistics of the detected flow patterns are calculated. The color pixel density and the mean color value varies between recordings of the same image during subsequent systolic peaks with a SD of 10% and 2%, respectively, and within different sections of the same organ or tumor with 25% and 10-50%. This analysis can be used for comparative or longitudinal studies and an objective evaluation of CD in complex vascular formations such as tumors. Its diagnostic impact has already been demonstrated in clinical studies.
Asunto(s)
Vasos Sanguíneos/diagnóstico por imagen , Procesamiento de Imagen Asistido por Computador , Ultrasonografía Doppler en Color , Velocidad del Flujo Sanguíneo , Presentación de Datos , Diagnóstico por Computador , Diagnóstico Diferencial , Humanos , Procesamiento de Imagen Asistido por Computador/métodos , Almacenamiento y Recuperación de la Información , Estudios Longitudinales , Microcomputadores , Neoplasias/irrigación sanguínea , Neoplasias/diagnóstico por imagen , Flujo Pulsátil , Reproducibilidad de los Resultados , Procesamiento de Señales Asistido por Computador , Sístole , Glándula Tiroides/irrigación sanguínea , Glándula Tiroides/diagnóstico por imagen , Ultrasonografía Doppler en Color/métodos , Grabación en VideoRESUMEN
Conventional pulse oximeters are accurate at high oxygen saturation under a variety of physiological conditions but show worsening accuracy at lower saturation (below 70%). Numerical modeling suggests that sensors fabricated with 735 and 890 nm emitters should read more accurately at low saturation under a variety of conditions than sensors made with conventionally used 660 and 900 nm band emitters. Recent animal testing confirms this expectation. It is postulated that the most repeatable and stable accuracy of the pulse oximeter occurs when the fractional change in photon path lengths due to perturbations in the tissue (relative to the conditions present during system calibration) is equivalent at the two wavelengths. Additionally, the penetration depth (and/or breadth) of the probing light needs to be well matched at the two wavelengths in order to minimize the effects of tissue heterogeneity. At high saturation these conditions are optimally met with 660 and 900 nm band emitters, while at low saturation 735 and 890 nm provide better performance.