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C Bingham

Publications and source records attributed to C Bingham.

29 records · Page 2Linked to original sources
PubMedDate not supplied

From experimental units to unique experiments: chronobiologic pilots complement large trials.

The timing of treatment affects outcome. For mapping multi-frequency rhythm spectra first to optimize chronochemotherapy, 1000 marker determinations on the subject are more informative than a few determinations on each of hundreds of patients. N-of-6 subgroups should follow, with one subject assigned to each of 6 marker rhythm stages, 60 (e.g. 4 hours on a 24-hour scale) apart. Once the time structure has been mapped, minimal sampling requirements determined, and guidelines for treatment established, the information gained from chronobiologic n-of-1 and n-of-6 test pilot designs can be built cost-effectively into randomized controlled trials to benefit large patient populations. Sequential tests combined with marker rhythmometry and cosinor analysis on single test subjects, small groups and eventually on each patient are powerful tools that can extract information otherwise unattainable even at great cost and bring the P-value from publications to the patients.

Antineoplastic Agents↗
PubMedDate not supplied

Chronosynergistic effects of lighting schedule-shift and cefodizime on plasmacytoma growth and host survival time.

Lighting regimen shifts can modify the effects of cefodizime, for the purpose of a chronoimmunomodulation. Two experiments were carried out on male and female LOU rats inoculated subcutaneously with plasmacytoma cells. Some rats were kept on their original LD12:12 regimen, whereas others, after tumor implantation, were subjected every second day to 6-h shifts, instituted, in alternation, as advance or delay. Daily treatment with cefodizime or placebo started when, overall, about 50% of the animals had developed a palpable tumor. A subgroup of animals contributed daily smears for the determination of the estrus cycle and further provided core temperature and activity data by telemetry. In Experiment I, the repeated shifting of the LD regimen was associated with survival time prolongation (p less than 0.05), irrespective of drug administration. Moreover, in those (female) rats repeatedly exposed to shifts of the lighting schedule, cefodizime was found to prolong survival time (p less than 0.05). The effects of cefodizime vs placebo on survival time were found to be circadian stage-dependent. In Experiment II, differing from Experiment I in the initial conditions before the institution of the shifts, cefodizime treatment was associated with a prolongation of survival time of the female rats kept on a fixed LD12:12 regimen. Both male and female rats again showed a circadian stage-dependence of the cefodizime effect. These results suggest that interactions between synchronizers of rhythms (such as shifts of the lighting regimen, the latter simulating the daily routine) and immunomodulating agents such as cefodizime may be optimized to improve treatment strategies against cancer and other diseases.

Animals↗
PubMedDate not supplied

Testing period for single cosinor: extent of human 24-h cardiovascular 'synchronization' on ordinary routine.

A clinically healthy woman monitored her systolic and diastolic blood pressure and pulse for 26 days at approximately 10-min intervals, with interruptions. Data over subspans of varying length were analyzed by single cosinor. A method for testing a period assumed to characterize data analyzed by single cosinor was introduced and programmed to compute a 95% confidence interval for the circadian period. Statistically significant deviations from precisely 24 h were found. The likelihood of their occurrence was found to vary as a function of the length of the interval analyzed. Under ordinary conditions in health, the circadian period may vary around 24 h, indicating that strict frequency-synchronization with the environment need not occur on a short-term basis. Deviations from an average circadian period may be brought about in part by infradian components modulating the circadian rhythm and by day-to-day changes in waveform.

Blood Pressure↗
PubMedDate not supplied

Chronobiologic serial sections of several orders.

The chronobiologic serial section is described. Its applicability to the analysis of nonequidistant data is emphasized. Its ability to detect and quantify multiple components is discussed and exemplified on simulated series with various amounts of additive Gaussian noise. This least-squares method is discussed in the context of a number of complementary procedures such as complex demodulation and linear-nonlinear least-squares rhythmometry.

Animals↗
PubMedDate not supplied

Construction of rhythm-specified reference intervals and regions, with emphasis on 'hybrid' data, illustrated for plasma cortisol.

Time-specified reference intervals, so-called chronodesms for the interpretation of single samples, have heretofore been proposed for longitudinal data, consisting of repeated samples from a single individual, and for transverse data: single time-specified samples from many individuals. Herein the problem of dealing with hybrid data, namely time series of data collected on a group of subjects, is considered for a derivation of reference intervals that take into account both inter- and intra-individual variability. The formulae are applied to cortisol data (72 samples from each of 10 healthy young adult North American women) with interpretation from both Bayesian and frequentist viewpoints. The provision of reference limits for both single samples and paired rhythm characteristics offers the opportunity of introducing an overdue time-specification and time-structure evaluation into microscopic chronobiology and through it into medical, veterinarian and other practice.

Adult↗
PubMedDate not supplied

Cross-spectral coherence between geomagnetic disturbance and human cardiovascular variables at non-societal frequencies.

A 35-year-old cardiologist monitored himself with an automatic ABPM-630 (Colin Electronics) monitor, mostly at 15-minute intervals around-the-clock for three years with a few interruptions. In this subject with a family history of high blood pressure and stroke, a cross-spectral analysis revealed a statistically significant coherence at 27.7 days between systolic and diastolic blood pressure and heart rate vs. the geomagnetic disturbance index, Kp. A lesser peak in coherence was found for systolic blood pressure with Kp at a trial period of 4.16 days (P = 0.046). These results suggest that changes in geomagnetism may influence the human circulation, at least in the presence of familial cardiovascular disease risk, and they may do so at frequencies that have no precise human-made cyclic worldwide match.

Adult↗
PubMedDate not supplied

Telehygiene system for preventive chronopharmacology in space and remote areas on earth.

A chronobiologic computerized modular health care (telehygiene) system for humans in extraterrestrial space 1) monitors and analyzes physiologic blood pressure, heart rate and other variation, including that in tumor markers; 2) recognizes earliest risk elevation by dynamic changes in the 'usual value' range (trend and rhythm alteration); 3) prompts timely and timed treatment for cardiovascular and emotional disease and malignancy prevention, and 4) serves for health improvement; the information from the system can also help optimize shift-work schedules for peak performance and provides endpoints of interest in basic science. The system exploits the chronome, a genetically anchored, habitat-synchronized structure of multifrequency rhythms and trends which is now documented (by longitudinal data series) to respond to magnetic disturbance in the solar system, with consequences expressed in catastrophic illness that is best prevented. Such a system, rated by peers as being of highest priority, could complement classical tools such as the stethoscope, proposed by the U.S. Johnson Space Center representative for use on the moon.

Aerospace Medicine↗