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P Delmore

Publications and source records attributed to P Delmore.

At least 19 recordsLinked to original sources
PubMed2005

Chronomics, neuroendocrine feedsidewards and the recording and consulting of nowcasts--forecasts of geomagnetics.

A multi-center four-hourly sampling of many tissues for 7 days (00:00 on April 5-20:00 to April 11, 2004), on rats standardized for 1 month in two rooms on antiphasic lighting regimens happened to start on the day after the second extremum of a moderate double magnetic storm gauged by the planetary geomagnetic Kp index (which at each extremum reached 6.3 international [arbitrary] units) and by an equatorial index Dst falling to -112 and -81 nT, respectively, the latter on the first day of the sampling. Neuroendocrine chronomes (specifically circadian time structures) differed during magnetically affected and quiet days. The circadian melatonin rhythm had a lower MESOR and lower circadian amplitude and tended to advance in acrophase, while the MESOR and amplitude of the hypothalamic circadian melatonin rhythm were higher during the days with the storm. The circadian parameters of circulating corticosterone were more labile during the days including the storm than during the last three quiet days. Feedsidewards within the pineal-hypothalamic-adrenocortical network constitute a mechanism underlying physiological and probably also pathological associations of the brain and heart with magnetic storms. Investigators in many fields can gain from at least recording calendar dates in any publication so that freely available information on geomagnetic, solar and other physical environmental activity can be looked up. In planning studies and before starting, one may gain from consulting forecasts and the highly reliable nowcasts, respectively.

Animals↗
PubMed2001

Collaborative quality improvement for neonatal intensive care. NIC/Q Project Investigators of the Vermont Oxford Network.

OBJECTIVE: To make measurable improvements in the quality and cost of neonatal intensive care using a multidisciplinary collaborative quality improvement model. DESIGN: Interventional study. Patient demographic and clinical information for infants with birth weight 501 to 1500 g was collected using the Vermont Oxford Network Database for January 1, 1994 to December 31, 1997. SETTING: Ten self-selected neonatal intensive care units (NICUs) received the intervention. They formed 2 subgroups (6 NICUs working on infection, 4 NICUs working on chronic lung disease). Sixty-six other NICUs served as a contemporaneous comparison group. PATIENTS: Infants with birth weight 501 to 1500 g born at or admitted within 28 days of birth between 1994 and 1997 to the 6 study NICUs in the infection group (n = 3063) and the 66 comparison NICUs (n = 21 509); infants with birth weight 501 to 1000 g at the 4 study NICUs in the chronic lung disease group (n = 738). INTERVENTIONS: NICUs formed multidisciplinary teams that worked together under the direction of a trained facilitator over a 3-year period beginning in January 1995. They received instruction in quality improvement, reviewed performance data, identified common improvement goals, and implemented "potentially better practices" developed through analysis of the processes of care, literature review, and site visits. MAIN OUTCOME MEASURES: The rates of infection after the third day of life with coagulase-negative staphylococcal or other bacterial pathogens for infants with birth weight 501 to 1500 g, and the rates of oxygen supplementation or death at 36 weeks' adjusted gestational age for infants with birth weight 501 to 1000 g. RESULTS: Between 1994 and 1996, the rate of infection with coagulase-negative staphylococcus decreased from 22.0% to 16.6% at the 6 project NICUs in the infection group; the rate of supplemental oxygen at 36 weeks' adjusted gestational age decreased from 43.5% to 31.5% at the 4 NICUs in the chronic lung disease group. There was heterogeneity in the effects among the NICUs in both project groups. The changes observed at the project NICUs for these outcomes were significantly larger than those observed at the 66 comparison NICUs over the 4-year period from 1994 to 1997. CONCLUSION: We conclude that multidisciplinary collaborative quality improvement has the potential to improve the outcomes of neonatal intensive care.

Chronic Disease↗
PubMed2000

High-versus low-threshold surfactant retreatment for neonatal respiratory distress syndrome.

UNLABELLED: Surfactant therapy has become an effective standard therapy for infants with respiratory distress syndrome (RDS). The first dose may be given either as prophylaxis immediately after delivery, or as rescue after an infant has developed RDS. Second and subsequent doses are currently recommended by the manufacturers to be administered at minimal levels of respiratory support. PURPOSE: This study compared the relative efficacy of administering second and subsequent doses of Infasurf surfactant at a low threshold (FIO(2) >30%, still requiring endotracheal intubation) versus a high threshold (FIO(2) >40%, mean airway pressure >7 cm H(2)O) of respiratory support. METHODS: A total of 2484 neonates received a first dose of surfactant; 1267 reached conventional retreatment criteria and were randomized to be retreated according to low- or high-threshold criteria. They were then retreated at a minimum of 6-hour intervals each time they reached their assigned threshold until receiving a maximum of 4 total doses. Subjects were stratified by whether they received their first dose by prophylaxis or rescue and by whether their lung disease was considered complicated (evidence of perinatal compromise or sepsis) or uncomplicated. RESULTS: Among the patients randomized, 33% of prophylaxis and 23% of rescue subjects met criteria for the complicated stratum. Although infants allocated to the high-threshold strategy were receiving slightly more oxygen at 72 hours, there was no difference in the number receiving mechanical ventilation at 72 hours or in the secondary respiratory outcomes (requirement for supplemental oxygen or mechanical ventilation at 28 days, supplemental oxygen at 36 weeks' postconceptional age, inspired oxygen concentration >60% at any time). However, there was a significantly higher mortality for infants with complicated RDS who had received retreatment according to the high-threshold strategy. CONCLUSIONS: We conclude that equal efficacy can be realized by delaying surfactant retreatment of infants with uncomplicated RDS until they have reached a higher level of respiratory support than is the current standard. We speculate that this would result in a substantial cost-saving from less utilization of drug. Conversely, we believe that infants with complicated RDS should continue to be treated by the low-threshold retreatment strategy, which is currently recommended by the manufacturers of the commercially available surfactants.

Biological Products↗
PubMed1993

Prophylactic administration of calf lung surfactant extract is more effective than early treatment of respiratory distress syndrome in neonates of 29 through 32 weeks' gestation.

OBJECTIVE: Although numerous trials have demonstrated the efficacy of exogenous surfactant for prophylaxis or treatment of neonatal respiratory distress syndrome (RDS), optimum timing of administration remains controversial. One previous study showed that administration of calf lung surfactant extract immediately following birth, to neonates born before 30 weeks postconceptional age, was preferable to delaying administration until after development of RDS. The current study was designed to test a similar hypothesis for babies born between 29 and 32 weeks gestational age. DESIGN: One thousand three hundred ninety-eight neonates with obstetric estimates of 29 through 32 weeks' gestation were randomized to receive CLSE at birth or to wait until development of mild RDS. After exclusions for malformations and other factors, data from 1248 were analyzed. RESULTS: Prophylaxis was associated with less development of moderate RDS (7% vs 12%), less need for retreatment (5% vs 9%), less need for mechanical ventilation or supplemental oxygen during the first 4 days, and fewer deaths or less requirement for supplemental oxygen at 28 days (5% vs 9%). Although 1-minute Apgar scores were significantly lower in the prophylaxis group, the difference disappeared by the 5-minute score and there was no difference in the incidence of asphyxia-related complications. Sixty percent of the neonates assigned to early treatment received endotracheal intubation and 43% received calf lung surfactant extract at a median age of 1.5 hours. When data were analyzed by gestational age and birth weight subgroups, most of the differences could be attributable to babies born at 30 weeks or less or weighing less than 1500 g, probably because of the higher incidence of surfactant deficiency in this more immature subgroup.

Drug Administration Schedule↗
PubMed1990

Respiratory distress syndrome and tracheoesophageal fistula: management with high-frequency ventilation.

An 1180-g infant with esophageal atresia and tracheoesophageal fistula developed life-threatening respiratory distress syndrome. Conventional mechanical ventilation resulted in gastric perforation and pneumoperitoneum. High-frequency ventilation stabilized the infant, permitting distal occlusion of the esophagus with a Silastic band. Fistula ligation was subsequently performed under more optimal physiologic conditions.

Esophageal Atresia↗
PubMed1989

Early and late surfactant treatment in preterm triplets.

Preterm triplets were treated with calf lung surfactant extract (CLSE). Two were treated at birth without development of respiratory distress syndrome (RDS); one was treated after development of RDS, with rapid improvement. These cases demonstrated the efficacy of exogenous surfactant and the potential benefit of prophylaxis (early treatment) over late treatment. Although various exogenous surfactants have been used successfully to treat or prevent RDS in preterm infants, the optimal time of surfactant treatment has not been established. Surfactant therapy at birth results in a reduction in the incidence and severity of RDS, but it could lead to unnecessary treatment in a significant portion of patients. On the other hand, delaying treatment is likely to lessen the benefits of exogenous surfactant by various factors, including barotrauma and oxygen toxicity. The triplets in this report were treated with Infasurf CLSE. Two were treated at birth without development of RDS, but one was treated after development of RDS, with rapid improvement of respiratory status.

Female↗
PubMedDate not supplied

Rewards in practice from chrono-meta-analyses 'recycling' heart rate, ectopy, ischemia and blood pressure information.

Previously published average curves of heart rate and duration of ischemia in patients with coronary artery disease, studied while on placebo or on treatment with either atenolol or diltiazem, are re-analysed for the assessment of about-daily (circadian) and about-weekly (circaseptan) changes in these variables and of any treatment effect on rhythm characteristics. In addition to circadians, a circaseptan pattern characterizes the duration of ischemia in all three aforementioned study stages. Both drugs decrease the duration of ischemia, atenolol, but not diltiazem, also affects the circadian amplitude and acrophase of this variable. A circaseptan pattern is also found for heart rate on placebo and on treatment with atenolol, but not with diltiazem. Both drugs lower heart rate and the circadian amplitude and 24-h standard deviation of heart rate, atenolol much more markedly than diltiazem. Circadian and circaseptan rhythm characteristics and their alterations with treatment serve to optimize treatment by timing its administration. Chronobiologic surveillance of variables that are being readily monitored as-one-goes by modern implantable devices can also serve for the validation of the effectiveness of drug and electrical therapy. Rhythm alterations, in turn, can provide the earliest warnings of an elevated disease risk and lead to an improved diagnosis.

Adult↗
PubMedDate not supplied

Chronomes, time structures, for chronobioengineering for "a full life".

Week-long or longer monitoring of blood pressure and heart rate, coupled to time-structure analyses, can help detect disease-risk elevations, as a warning of the need for a preventive prehabilitation. Within the normal range of physiologic variation, computer methods quantify time structures, or chronomes, that can serve as reference values. The major applied purpose for mapping chronomes is the detection of disease-risk syndromes such as blood pressure "overswinging" and heart rate "underswinging." Too much blood pressure variability (circadian hyperamplitude tension; CHAT), is a risk factor for vascular disease. Other risk syndromes are chronome alterations of heart rate variability (CAHRVs), consisting of a loss of "jitter", i.e., a reduced standard deviation of heart rate or of alterations in the spectral element of the heart-rate-variability chronome, such as in the correlation dimension, an endpoint of deterministic chaos. These alterations can again serve for prehabilitation. On the basic side, the spectral element of the heart-rate-variability chronomes extends from focus on the heartbeat's period of about 1 second to periods in heart rate and its standard deviation that are numerical equivalents of about 10.5- and about 21-year cycles of solar activity. A seemingly unnatural physiologic rhythm or pattern (such as one of 81.6 hours) may correspond numerically to a purely physical environmental rhythm. For example, interplanetary magnetic storms, with their cycles as external chronome components, trigger myocardial infarctions, strokes, and traffic accidents. The systematic monitoring of external rhythms along with physiologic ones for the concurrent analysis of rhythms with longer and longer periods could detect alterations anywhere in and between the 1 cycle/sec and the 1 cycle/10.5- or 21-years regions of the spectrum. Chronobiomimetic engineering for discovering both instantaneous and long-term chronorisk alterations can provide warnings of increased risk. If risk-lowering therapy is then instituted automatically, instrumented health care will be extended beyond the pacemaker-cardioverter-defibrillator, which focuses on the frequency of 1 cycle/sec. Instrumentation that automatically detects blood pressure that varies too much and heart rate that varies too little is needed for prompting prophylactic CHAT and CAHRV treatment. A database of reference values that can be used for chronodiagnosis is now accumulating.

Accidents, Traffic↗
PubMedDate not supplied

Spin-offs from blood pressure and heart rate studies for health care and space research.

Evidence here cited underlies resolutions at international meetings to initiate a chronobiology project for health improvement. This project demonstrates expeditiously the feasibility and the health benefits of incorporating chronomedical considerations in the diagnosis, treatment, and prevention of one (or a few closely related) vascular (and oncological) diseases, that have high awareness and importance in the public perspective. Thereby, chronomedicine should become a mainstream basic and applied speciality leading to continual improvement in national/international health status. Reference data obtained for health care can also serve to give a better understanding of the relationship between the terrestrial biosphere and cosmoi near and far.

Blood Pressure↗
PubMedDate not supplied

Chronobiology: a frontier in biology and medicine.

On the occasion of Franz Halberg's 70th birthday, some of his many achievements are reviewed. We provide a historical background to the development of chronobiology; offer insight into the current state of this new science; and sketch the promise of this discipline for health care and cure. As a tribute to Franz Halberg, in an era of fast-growing technology, an attempt is made to describe his perspective of tomorrow's medicine and biology. The many students he trained throughout his productive career face the challenge of deserving the trust he placed in them and of further implementing his vision. A leader in social pediatrics put it aptly: it will take several generations of researchers to study and master his life's work.

Animals↗