SUMMARY A method for the volumetric assessment of early cerebral infarction, together with its statistical and biological validation, is described. In halothane anaesthetised rats the stem of the right middle cerebral artery was occluded and 3 hours later (with full monitoring of respiratory and cardiovascular status) the animals were killed by perfusion fixation. In normotensive normocapnic animals the volume of infarction was 52 + 4mm3 in the cerebral cortex and 21 + 1 mm3 in the corpus striatum. The reproducibility of the volumetric assessment was found to be excellent (coefficient of correlation 0995 on 18 replicate measurements). The minimum number of stereotactic levels which must be assessed to yield accurate volumetric measurements of infarction is 8. The method is sensitive at detecting alterations in the amount of infarction. For example, it can readily detect the increase in amount of structural damage in cerebral cortex following a transient episode of hypotension. This approach allows an objective assessment of drug therapy and management strategies in the treatment of cerebral infarction.Numerous attempts have been made to produce experimentally an ischaemic lesion resembling that seen in man. One of the most commonly used methods has been to occlude the middle cerebral artery in various experimental animals`6 in the belief that proximal occlusion of this artery is equivalent to a large focal cerebral infarct in man.We have developed a technique for occluding the middle cerebral artery (MCA) in the rat7 which has proved useful for correlating local cerebral blood flow8 and dysfunction of the blood-brain barrier9 with histological evidence of ischaemic brain damage. 10 In this paper we detail a rigorous means for measuring the volume of early cerebral infarction in the rat after occlusion of the middle cerebral artery. This method, with its statistical validation, together with a demonstration of its ability to measure changes in the amount of structural damage in various experimental conditions, is described. Some of this data has appeared previously in abstract form." Materials and methods
General preparationThirteen adult male Sprague Dawley rats (weighing between 320-415 g each) were anaesthetised and ventilated mechanically with a nitrous oxide/oxygen mixture (70%:30%) and, during the surgical procedures, 2% halothane. Polyethylene catheters were inserted into both femoral arteries and veins to allow the continuous monitoring of blood pressure, repeated sampling of arterial blood and the administration of drugs. The body temperature was monitored by a rectal thermometer and the animals were maintained at normothermia by external heating.In normotensive animals, if there was a transient reduction in mean arterial blood pressure below 80mm Hg for more than two minutes during the observation period of 3-4 hours after occlusion of the MCA, the animals were not processed for inclusion in the study.Operative procedure The proximal portion of the MCA was occluded permanently under halothane anaesthesi...
Ceritinib, 450 mg with food, had similar exposure and a more favorable GI safety profile than ceritinib, 750 mg in fasted patients with ALK-positive NSCLC.
Objectives
To identify variables associated with successful elective extubation, and to determine neonatal morbidities associated with extubation failure in extremely preterm neonates.
Study design
This study was a secondary analysis of the National Institute of Child Health and Human Development Neonatal Research Network’s Surfactant, Positive Pressure, and Oxygenation Randomized Trial that included extremely preterm infants born at 240/7 to 276/7 weeks’ gestation. Patients were randomized either to a permissive ventilatory strategy (continuous positive airway pressure group) or intubation followed by early surfactant (surfactant group). There were prespecified intubation and extubation criteria. Extubation failure was defined as reintubation within 5 days of extubation.
Results
Of 1316 infants in the trial, 1071 were eligible; 926 infants had data available on extubation status; 538 were successful and 388 failed extubation. The rate of successful extubation was 50% (188/374) in the continuous positive airway pressure group and 63% (350/552) in the surfactant group. Successful extubation was associated with higher 5-minute Apgar score, and pH prior to extubation, lower peak fraction of inspired oxygen within the first 24 hours of age and prior to extubation, lower partial pressure of carbon dioxide prior to extubation, and non-small for gestational age status after adjustment for the randomization group assignment. Infants who failed extubation had higher adjusted rates of mortality (OR 2.89), bronchopulmonary dysplasia (OR 3.06), and death/bronchopulmonary dysplasia (OR 3.27).
Conclusions
Higher 5-minute Apgar score, and pH prior to extubation, lower peak fraction of inspired oxygen within first 24 hours of age, lower partial pressure of carbon dioxide and fraction of inspired oxygen prior to extubation, and nonsmall for gestational age status were associated with successful extubation. Failed extubation was associated with significantly higher likelihood of mortality and morbidities.
Trial registration
ClinicalTrials.gov: NCT00233324.
Adding EVE to EXE offers substantially improved PFS over EXE and was generally well tolerated in elderly patients with HR(+) advanced breast cancer. Careful monitoring and appropriate dose reductions or interruptions for AE management are recommended during treatment with EVE in this patient population.
Administration of recombinant G-CSF to infants with neutropenia and clinical signs of early-onset sepsis did not increase circulating ANC, or bone marrow NSP and NPP compared with placebo. No differences were observed between G-CSF and placebo recipients in severity of illness, morbidity, or mortality. No adverse effects of G-CSF administrations were noted.
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