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1.
J Perinatol ; 42(9): 1183-1188, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35449444

RESUMEN

BACKGROUND: Congenital diaphragmatic hernia (CDH) accounts for 8% of all major congenital anomalies. Neonates who are small for gestational age (SGA) generally have a poorer prognosis. We sought to identify risk factors and variables associated with outcomes in neonates with CDH who are SGA in comparison to neonates who are appropriate for gestational age (AGA). METHODS: We used the multicenter Diaphragmatic Hernia Research & Exploration Advancing Molecular Science (DHREAMS) study to include neonates enrolled from 2005 to 2019. Chi-squared or Fisher's exact tests were used to compare categorical variables and t tests or Wilcoxon rank sum for continuous variables. Cox model analyzed time to event outcomes and logistic regression analyzed binary outcomes. RESULTS: 589 neonates were examined. Ninety were SGA (15.3%). SGA patients were more likely to be female (p = 0.003), have a left sided CDH (p = 0.05), have additional congenital anomalies and be diagnosed with a genetic syndrome (p < 0.001). On initial single-variable analysis, SGA correlated with higher frequency of death prior to discharge (p < 0.001) and supplemental oxygen requirement at 28 days (p = 0.005). Twice as many SGA patients died before repair (12.2% vs 6.4%, p = 0.04). Using unadjusted Cox model, the risk of death prior to discharge among SGA patients was 1.57 times the risk for AGA patients (p = 0.029). There was no correlation between SGA and need for ECMO, pulmonary hypertensive medication at discharge or oxygen at discharge. After adjusting for confounding variables, SGA no longer correlated with mortality prior to discharge or incidence of unrepaired defects but remained significant for oxygen requirement at 28 days (p = 0.03). CONCLUSION: Infants with CDH who are SGA have worse survival and poorer lung function than AGA infants. However, the outcome of SGA neonates is impacted by other factors including gestational age, genetic syndromes, and particularly congenital anomalies that contribute heavily to their poorer prognosis.


Asunto(s)
Oxigenación por Membrana Extracorpórea , Hernias Diafragmáticas Congénitas , Femenino , Edad Gestacional , Hernias Diafragmáticas Congénitas/complicaciones , Humanos , Lactante , Recién Nacido , Masculino , Oxígeno , Estudios Retrospectivos , Factores de Riesgo
2.
Stand Genomic Sci ; 1(1): 78-86, 2009 Jul 20.
Artículo en Inglés | MEDLINE | ID: mdl-21304641

RESUMEN

The principles underlying fair and equitable sharing of benefits derived from the utilization of genetic resources are set out in Article 15 of the UN Convention on Biological Diversity, which stipulate that access to genetic resources is subject to the prior informed consent of the country where such resources are located and to mutually agreed terms regarding the sharing of benefits that could be derived from such access. One issue of particular concern for provider countries is how to monitor and track genetic resources once they have left the provider country and enter into use in a variety of forms. This report was commissioned to provide a detailed review of advances in DNA sequencing technologies, as those methods apply to identification of genetic resources, and the use of globally unique persistent identifiers for persistently linking to data and other forms of digital documentation that is linked to individual genetic resources. While the report was written for an audience with a mixture of technical, legal, and policy backgrounds it is relevant to the genomics community as it is an example of downstream application of genomics information.

3.
Ultrasonics ; 39(3): 181-94, 2001 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-11349999

RESUMEN

A pulse-compression technique has been applied to air-coupled testing of solid materials. Capacitance transducers were used to generate wide bandwidth swept-frequency (chirp) signals in air, which were then used to measure and image solid samples in through transmission. The results demonstrate that such signal processing techniques lead to an improvement in the signal to noise ratio and timing accuracy for air-coupled testing. Measurements of thickness and spectroscopic experiments are presented. Images of defects in a wide range of materials, including metals and carbon-fibre composites have also been obtained. This combination of capacitive transducers with pulse-compression techniques is shown to be a powerful tool for non-contact air-coupled ultrasonic measurements.


Asunto(s)
Procesamiento de Señales Asistido por Computador , Ultrasonido , Procesamiento de Imagen Asistido por Computador , Transductores
4.
J Pediatr Surg ; 35(6): 940-2, 2000 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-10873040

RESUMEN

BACKGROUND/PURPOSE: Biliary anastomotic strictures (BAS) after left lateral segment liver transplantation (LLST) may cause graft dysfunction, sepsis, and patient mortality. A review of the authors' experience was performed to better characterize the risk factors and corrective management. METHODS: The medical records of 9 children who underwent a LLST in whom a BAS developed from 1989 to the present were reviewed retrospectively. RESULTS: Seventy-five of 199 liver transplants (38%) at the authors' institution since 1989 have been LLST. BAS developed in 12% of these cases. BAS were diagnosed less than 12 months after transplantation in 4 children (mean, 7.5 months; range, 5 to 11 months) and greater than 12 months in 5 children (mean, 37 months; range, 14 to 72 months). Early strictures (<12 months) were associated with hepatic artery thrombosis (n = 1), and posttransplant bile leak (n = 1) and ducts from segment II and III exiting separately from the left lateral segment (n = 2). The diagnosis of BAS was heralded by episodes of liver biopsy-proven cholangitis in all patients and confirmed radiographically. Seven children underwent successful biliary exploration and revision of the hepaticojejunostomy. Two of these children ultimately required retransplantation secondary to chronic graft rejection. CONCLUSIONS: BAS in LLST are a source of significant morbidity and should be considered in children after LLST who present with cholangitis. Surgical correction is possible in most cases.


Asunto(s)
Conductos Biliares/cirugía , Colestasis/cirugía , Trasplante de Hígado/efectos adversos , Adolescente , Anastomosis Quirúrgica/efectos adversos , Conductos Biliares/patología , Niño , Preescolar , Colestasis/etiología , Constricción Patológica , Femenino , Humanos , Lactante , Masculino , Estudios Retrospectivos
5.
J Pediatr Surg ; 35(2): 297-300; discussion 301-2, 2000 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-10693684

RESUMEN

BACKGROUND/PURPOSE: Children who require a liver transplant at an early age risk chronic allograft rejection (CAR) and other causes of allograft loss. Multiple retransplants may be required for long-term patient survival. The authors evaluate this approach based on our results and technical difficulties. METHODS: Charts of 7 children who received 3 or more liver transplants from 1989 to the present were reviewed retrospectively. RESULTS: A total of 151 children required liver transplantation at our institution since 1989. Of these, 4 boys and 3 girls (mean age, 6.2 years; range, 3 to 14 years) have received 3 or more allografts. The etiology of liver failure for the penultimate allograft was CAR (n = 6) and hepatic artery thrombosis (HAT; n = 1). Five cases required modification of portal vein or hepatic artery anastomoses. Two patients with vena caval strictures required supradiaphragmatic vena caval reconstruction. The original Roux-en-Y limb was adequate for biliary reconstruction in all cases. Five children currently are alive (survival rate, 71%) with good graft function having had a mean follow-up of 23 months (range, 2 to 48 mos.). CONCLUSIONS: The operative procedure for the multiple hepatic transplant child is challenging. The transplant team must be prepared for intraoperative issues such as extended organ ischemia time during hepatectomy, extensive blood loss, and potential need for creative organ revascularization techniques. Overall, multiple retransplant results are good and justify the use of multiple allografts.


Asunto(s)
Atresia Biliar/cirugía , Trasplante de Hígado , Adolescente , Niño , Preescolar , Colestasis/cirugía , Femenino , Rechazo de Injerto , Humanos , Masculino , Reoperación , Estudios Retrospectivos , Resultado del Tratamiento , Tirosinemias/sangre
6.
Artículo en Inglés | MEDLINE | ID: mdl-18238420

RESUMEN

A micromachined Fresnel zone-plate has been used to focus ultrasonic waves in air over a range of frequencies (450 to 900 kHz). The zone-plate was mounted upon a planar micromachined air-coupled capacitance transducer, which was capable of generating toneburst ultrasonic waves in air over a wide frequency bandwidth (<100 kHz to 2 MHz). A second air-coupled capacitance detector (apertured to 200 microm) was scanned in the field of the zone-plate source in order to image the generated ultrasonic field at various frequencies of operation. It was found that the ~680 microm spot size of the experimental zone-plate did not vary appreciably with changing frequency, whereas the focal length increased markedly with increasing frequency (from ~5 mm at 450 kHz up to ~15 mm at 900 kHz). These findings are shown to be in excellent agreement with previously reported theoretical predictions by the authors.

7.
Artículo en Inglés | MEDLINE | ID: mdl-18244189

RESUMEN

Investigations into the characteristics of water-coupled ultrasonic capacitance transducers have been undertaken for a range of transducer configurations. The radiated fields have been scanned in water using a miniature hydrophone detector, and the results compared to theory based on a plane piston approach. Micromachined backplates in conjunction with thin Mylar and mica membranes have been investigated, together with aperture modifications such as an annulus and Fresnel zone plate. The measured results agree well with theory, thus demonstrating that wideband predictable performance (>8 MHz) is obtainable with such transducers. Additionally, pulse-echo C-scans of a Plexiglas plate containing an artificial defect have been undertaken with the capacitance transducer, in order to demonstrate that the capacitance transducer has sufficient sensitivity to allow routine nondestructive testing within immersion applications.

8.
J Pediatr Surg ; 32(7): 995-7; discussion 997-8, 1997 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-9247220

RESUMEN

OBJECTIVE: The aim of this study was to evaluate whether partial hepatectomy (PH) enhances the growth of implanted intrahepatic and subcutaneous tumor and whether octreotide (OCT) can alter tumor growth. METHODS: Ninety-one ACI rats (125 g) underwent a laparotomy; 51 had a 66% PH and 40 were controls. Morris hepatoma 3924A was implanted in the liver (IH) of 29 PH and 26 controls and subcutaneously (SC) in 22 PH and 14 control rats. OCT, 50 mg/kg, was administered intraperitoneally twice a day to 23 PH rats with IH (n = 15) or SC (n = 8) tumor implants. The remaining PH rats received a similar volume of saline (NS). PH and control animals were evaluated for tumor volume, metastases, and tumor and liver weight at 7 and 15 days. RESULTS: Group I (PH + IH + NS) showed a sixfold increase in IH tumor volume and 100% increase in metastases versus group II (controls + IH + NS) at 15 days postimplant (P < .01). Group III (PH + SC + NS) had a fourfold increase in SC tumor volume at 7 and 15 days versus group IV (control + SC + NS, P < .02). Group V (PH + IH + OCT) showed a tenfold reduction of IH tumor volume (P < .01) and 20% decrease in liver weight (P < .03) when compared with group I at 15 days. Group VI (PH + SC + OCT) similarly showed a threefold reduction of SC tumor volume (P < .01) and 20% decrease in tumor weight (P < .05) versus group III. CONCLUSION: Growth of IH and SC hepatoma is enhanced after PH and inhibited by OCT. This suggests that factors influencing hepatic replication also affect local and remote tumor growth. OCT action may be related to the presence of somatostatin receptors or caused by a direct antiproliferative effect.


Asunto(s)
Antineoplásicos Hormonales/uso terapéutico , Neoplasias Hepáticas Experimentales/tratamiento farmacológico , Neoplasias Hepáticas Experimentales/cirugía , Octreótido/uso terapéutico , Animales , Antineoplásicos Hormonales/farmacología , Hepatectomía , Regeneración Hepática/fisiología , Recurrencia Local de Neoplasia/prevención & control , Octreótido/farmacología , Ratas , Ratas Endogámicas ACI
9.
J Pediatr Surg ; 32(2): 312-5, 1997 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-9044143

RESUMEN

PURPOSE: Major burns are associated with a high mortality, an increased rate of bacterial translocation, and bone marrow suppression. This study evaluates the effect of interleukin-11 (IL-11), a bone marrow-derived growth factor on survival, intestinal cytoarchitecture, bacterial translocation, and bone marrow suppression in a highly lethal murine burn model with a lethal dose greater than 50. METHODS: C3H/HeJ 8 to 10-week-old mice underwent a standardized 32% total body surface area (TBSA) scald burn using a burn template. Mice were divided equally between groups receiving IL-11 (125 micrograms/kg, twice daily, subcutaneously [SC]) and 0.1% same-volume Bovine Serum Albumin (BSA) (0.2 mL, twice daily, sc). Animals were evaluated for mesenteric lymph node bacterial counts, intestinal mucosal villus height, number of mucosal crypt cell mitoses per 100 crypts, and peripheral platelet and total lymphocyte counts. Survival was calculated to 7 days postburn. RESULTS: At 24 hours postburn, IL-11-treated mice had significantly less enteric bacteria cultured from mesenteric lymph nodes (P < .001), increased intestinal crypt cell mitoses (P = .002) and intestinal villus height (P = .002), increased peripheral platelet (P = .002) and lymphocyte counts (P = .004), and an improved survival compared with BSA controls (P = .003). CONCLUSION: These data show that IL-11 improves survival, intestinal cytoarchitecture, reduces bacterial translocation, and reduces bone marrow suppression after a 32% TBSA burn in mice. These data imply that IL-11 cytokine therapy may be a useful adjunct in extensive burn injury.


Asunto(s)
Traslocación Bacteriana/efectos de los fármacos , Médula Ósea/efectos de los fármacos , Quemaduras/terapia , Interleucina-11/uso terapéutico , Animales , Quemaduras/sangre , Quemaduras/mortalidad , Modelos Animales de Enfermedad , Mucosa Intestinal/efectos de los fármacos , Mucosa Intestinal/patología , Recuento de Leucocitos , Ganglios Linfáticos/microbiología , Masculino , Ratones , Ratones Endogámicos C3H , Ratones Endogámicos , Recuento de Plaquetas
10.
Artículo en Inglés | MEDLINE | ID: mdl-18244101

RESUMEN

An entirely air-coupled inspection system using a pair of micromachined silicon capacitance transducers has been used to image defects in thin plates of different materials (0.7 mm to 2.22 mm thick) using air-coupled Lamb wave tomography. A filtered back projection algorithm was used in a form of difference tomography to reconstruct images of defects up to 10 mm diameter machined in aluminium and perspex (Plexiglas) plates, as well as in samples of carbon fiber reinforced polymer (CFRP). The technique was able to resolve non-central defects as well as multiple flaws within the scan area. This flexible tomographic system was able to produce images of the change in a variety of different acoustic variables from only one set of experimental data, with success dependent on the size, shape, and location of the defect in the scan area.

11.
J Pediatr Surg ; 31(8): 1047-50; discussion 1050-1, 1996 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-8863231

RESUMEN

Interleukin-11 (IL-11) is a multifunctional cytokine, derived from bone marrow stromal cells, that stimulates proliferation of stem/progenitor precursor cells in the small intestinal crypts and accelerates recovery of intestinal mucosa after cytoablative therapy. This study evaluates whether IL-11 can improve the function and structure of the small intestine and enhance adaptation in an experimental model of short bowel syndrome. After 90% small bowel resection, 32 Sprague-Dawley rats were divided randomly into eight experimental groups of four animals each. Four groups were treated with IL-11 (125 micrograms/kg twice daily, subcutaneously), and the four control groups were treated with a similar volume (0.1%) of bovine serum albumin (BSA). The animals were weighed daily and were killed on day 2, 4, 6, or 8; remnant small bowel was evaluated for villus height and crypt cell mitosis. The body weight of the animals that received IL-11 was significantly greater at the beginning of postoperative day 4 in comparison to that of the BSA groups (P < .01 during days 5 to 7). The rats that had IL-11 also had significantly greater villus height and crypt cell mitotic rates (P < .05). These observations suggest that IL-11 has a trophic effect on the small bowel during the adaptive phase that follows massive bowel resection and may be useful in the treatment of short bowel syndrome.


Asunto(s)
Adaptación Fisiológica/inmunología , Interleucina-11/inmunología , Interleucina-11/uso terapéutico , Síndrome del Intestino Corto/tratamiento farmacológico , Síndrome del Intestino Corto/inmunología , Animales , Peso Corporal , Bovinos , Modelos Animales de Enfermedad , Evaluación Preclínica de Medicamentos , Mucosa Intestinal/citología , Mucosa Intestinal/crecimiento & desarrollo , Mucosa Intestinal/inmunología , Masculino , Mitosis , Distribución Aleatoria , Ratas , Ratas Sprague-Dawley , Albúmina Sérica Bovina/uso terapéutico
12.
Plast Reconstr Surg ; 90(6): 980-4; discussion 985-7, 1992 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-1448533

RESUMEN

The long-term effectiveness and safety of inferior turbinectomy were assessed in 186 patients who were interviewed and examined 10 to 15 years after surgery (mean 12.3 years). Relief of nasal obstruction was reported by 82 percent of the patients; rhinoscopy showed wide, clean nasal airways in 88 percent. Rhinorrhea was still a problem for 34 percent of patients, and 19 percent were receiving medical treatment for this symptom. Smell acuity had improved in 52 percent of the patients. Before turbinectomy, 32 patients had suffered from bronchial asthma; postoperatively, there was an improvement in 16, and no change in 13; 3 patients reported exacerbation of asthmatic attacks. Atrophic changes of the nasal mucosa and chronic purulent infection were not observed in any of the patients.


Asunto(s)
Obstrucción Nasal/cirugía , Cornetes Nasales/cirugía , Adolescente , Adulto , Asma/terapia , Niño , Enfermedad Crónica , Endoscopía , Exudados y Transudados/fisiología , Femenino , Estudios de Seguimiento , Humanos , Hipertrofia , Incidencia , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias , Ventilación Pulmonar/fisiología , Recurrencia , Seguridad , Olfato/fisiología , Cornetes Nasales/patología
13.
Prog Brain Res ; 82: 671-6, 1990.
Artículo en Inglés | MEDLINE | ID: mdl-2127120

RESUMEN

Treatment of refractory PD with autologous adrenal medullary implants utilizing two-stage surgery warrants further investigation. This transplantation technique is associated with prolonged transplant area BBB disruption which may require a change in medical treatment strategies including the withdrawal of peripheral dopa decarboxylase inhibitors and possible intravenous or intraventricular dopamine therapy. Of 5 patients receiving adrenal medullary transplants, 3 have demonstrated varying degrees of clinical improvement which has persisted for the duration of the study. The positive correlation between clinical outcome and caudate function (i.e., 6-fluorodopa PET scans) suggests a positive influence of the transplantation procedure on the diseased striatum. Whether or not the grafted tissue remains viable for an extended period is currently being investigated utilizing 6-FDG-PET studies. Because of the presence of persistent BBB disruption, we surmise that at least viability of implanted fenestrated adrenal medullary capillaries exists. We conclude that this prolonged leakage is the result of the implanted tissue rather than the cavitation procedure as prolonged BBB disruption was not witnessed in a control group of patients with post-traumatic cerebral contusions or in Parkinson's patients subjected to thalamotomies. Whether two-stage surgery results in increased graft viability, and host neuronal sprouting, leading to prolonged clinical improvement and slowing the progression of PD awaits continued longitudinal (greater than 24 months) studies.


Asunto(s)
Médula Suprarrenal/trasplante , Núcleo Caudado , Enfermedad de Parkinson/cirugía , Trasplante Heterotópico/métodos , Barrera Hematoencefálica , Núcleo Caudado/patología , Núcleo Caudado/cirugía , Dihidroxifenilalanina/análogos & derivados , Estudios de Seguimiento , Humanos , Persona de Mediana Edad , Enfermedad de Parkinson/diagnóstico por imagen , Tomografía Computarizada de Emisión , Trasplante Autólogo/métodos , Trasplante Heterotópico/efectos adversos , Trasplante Heterotópico/patología
15.
Disasters ; 10(3): 230-1, 1986 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-20958635

RESUMEN

Toxicological mass disasters have occurred frequently in past years and constitute a permanent threat in urban areas. From the standpoint of hospital planning, special consideration is required to treat a large number of poisoned casualties in a relatively short period. Several unique medical aspects characterize toxicological mass disasters: casualties present a single disease entity with many "borderline" cases, most medical personnel are unfamiliar with the problem and casualties present a potential contamination hazard to the hospital. A hospital deployment scheme is presented recommending Decontamination, Triage and simple Treatment Algorithms to meet the medical and organizational challenge of such a mass casualty situation. A further specific deployment scheme for treatment of organophosphorus agents poisoning is described to illustrate the principles presented.

18.
Science ; 214(4524): 1024-6, 1981 Nov 27.
Artículo en Inglés | MEDLINE | ID: mdl-17808668

RESUMEN

Warm-water marine gastropods from soft-bottom habitats show an increase in the incidence of breakage-resistant shell characteristics over geological time. The hypothesis that breakage became a more important component of selection in the middle of the Mesozoic Era is supported by the finding that frequencies of breakage-induced shell repair increased from the Pennsylvanian and Triassic periods to the Cretaceous, Miocene, and Recent.

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