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At least 379 records · Page 21Linked to original sources
PubMed2005

The effect of herbal medicine Toki-shakuyaku-san on blood pressure in an Nomega-nitro-L-arginine methyl ester-induced pre-eclampsia rat model during pregnancy and the postpartum period.

The chronic inhibition of nitric oxide (NO) synthesis with N(omega)-nitro-L-arginine methyl ester (L-NAME) in pregnant rats induces a pre-eclampsia-like syndrome, including hypertension. We have previously reported the beneficial effects of Toki-shakuyaku-san (TS) in this model. In the present study we demonstrated the anti-hypertensive effect of TS in pre-eclampsia produced by prolonged L-NAME-infusion during the postpartum period. Analysis of blood sex steroids suggested that the level of progesterone differs between the TS-effective (gestational day 19 and postpartum day 7) and TS-ineffective (postpartum day 1) periods. Co-administration of TS and progesterone inhibited L-NAME-induced hypertension on postpartum day 1. Furthermore, the anti-hypertensive effect of TS on postpartum day 6 disappeared in the presence of a co-administered progesterone antagonist mifepristone. These data suggest that a certain level of progesterone may be an indispensable prerequisite for an anti-hypertensive effect of TS. Finally, the effects of TS are apparently unrelated to blood levels of NO, calcitonin gene-related peptide, and endothelin-1, which have been reported to modulate systolic blood pressure in the L-NAME-induced pre-eclampsia model. Thus, the use of TS may provide a new therapeutic strategy for pre-eclampsia, although elucidation of the mechanism of action of TS would be necessary to optimize treatment protocols.

Animals↗
PubMedDate not supplied

Improving accuracy in a computerized immunization registry.

BACKGROUND: Boston's Department of Health and Hospitals established the Boston Immunization Information System (BIIS) as part of a city-wide effort to raise immunization rates. OBJECTIVES: Our objectives were 1) to assess the validity of data entry in one computerized immunization database within this system; 2) to identify the types of errors made in data entry; and 3) to assess the effectiveness of an intervention to improve the accuracy of information in this database. METHODS: Chart records were used as the gold standard in comparison with the computerized BIIS database. Children were considered up to date for immunizations if they had received 4 DTP, 3 polio, and 1 MMR by their second birthday. In March of 1995, billing records were used to identify all children born between March 1, 1992, and September 1, 1994, in one urban health center. These children were between 6 months and 36 months of age at the time. We compared the computer record with the chart, looking for and correcting errors such as incorrect dates and missing immunization data. An intervention was then begun, including a system for reviewing the accuracy of the computerized data at all well-child visits. In October of 1996, the chart review was repeated on children born between March 1, 1992, and September 1, 1995. This age range included all the children in the original review plus those born in the subsequent 12 months. Immunization rates before and after chart reviews were compared for children 24 to 36 months of age. RESULTS: We initially reviewed 737 of 739 charts (99%). In the follow-up time period, we examined 881 of 943 charts (93%). During the first review, 333 of the 563 (59%) records contained at least one error in data entry, compared with 116 of 646 (18%) in the second review (P <.0001). During the second review, we also examined the type of errors. Thirty-eight percent of all errors represented vaccines that had not been entered into the computer. Before the study period, analysis of the computerized immunization record showed an immunization up-to-date rate of 24%. This increased to 41% after the initial chart review and to 75% after the intervention period (P <.0001). CONCLUSION: Errors in data entry caused underestimates of immunization rates. Eliminating the errors increased immunization rates immediately through more accurate bookkeeping. Eighteen months later, immunization rates had continued to improve dramatically.

Boston↗
PubMed2004

Shorter hospital stay associated with fastrack postoperative care pathways and laparoscopic intestinal resection are not associated with increased physical activity.

OBJECTIVE: Recent prospective studies have shown that 'fast track' postoperative care protocols (FT) can reduce hospitalization after major intestinal surgery to 4.5 days, as compared to the 7-10 days with traditional management (TR) and 2.5 days after laparoscopic surgery (LC). We used computerized actigraphy (CA) to evaluate physical activity using TR, FT and LC approaches. METHODS: Fifteen patients undergoing intestinal resection by LC, TR and FT were recruited. CA devices were placed on the wrist and ankle of each patient from day 1 until hospital discharge. Intra-patient and intergroup analyses were performed using 24 h evaluations, and periods from 0800-2000 h. Results are presented for, level of activity (LOA; activity counts per minute), activity index (AI;% epochs with activity) and acceleration index (ACI; change in activity rate during analysis period) for 0800-2000 h. RESULTS: Levels of activity measured by wrist and ankle CA devices for the three different care protocols were: LC, 6263 +/- 8008 (wrist), 1640 +/- 3795 (ankle); FT 7874 +/- 8550 (wrist), 2153 +/- 4838 (ankle); LC 8526 +/- 9917 (wrist), 2326 +/- 4905 (ankle). Length of hospital stay was significantly shorter in LC than FT and TR patients (P < 0.01). There was no significant increase in wrist or ankle LOA for FT or LC patients. Similarly, there was no difference in AI or ACI. CONCLUSION: Although CA is an easily standardized method of evaluating physical activity after major abdominal surgery, no difference can be demonstrated between activity levels in patients managed by differing care pathways. Reductions in stay may be associated with factors other than a change in the level of physical activity after surgery.

Adult↗
PubMed2001

Effect of multislice CT technology on scanner productivity.

OBJECTIVE: In this study we analyzed the impact of multislice CT technology on scanner productivity in a tertiary care medical center. MATERIALS AND METHODS: We compared the productivity of two diagnostic CT scanners during the periods January 1 to August 31, 1999 (when both scanners had single-slice CT capability) and January 1 to August 31, 2000 (when one of these scanners was replaced with a multislice CT scanner). The scanners were used primarily for outpatients during the day shift and for inpatients during the evening shift; the demand for CT services was stable. For this analysis, we queried the hospital's radiology information system and identified the number of CT examinations performed during the two analysis periods. We also determined the examination mix, including proportion of enhanced and unenhanced examinations and the anatomic region examined, to ensure comparable patient populations. Statistical analysis was performed. RESULTS: The number of CT studies performed on the two scanners increased by 1772 (13.1%) from 13,548 (before multislice CT) to 15,320 (when multislice CT was available). The number of examinations enhanced with contrast media increased from 52% to 65%. Between 9:00 A.M. and 5:00 P.M., the number of CT examinations was similar on the single-slice scanners in the two periods (p > 0.05). However, in the period when multislice CT was available, the number of studies performed on the multislice scanner (5919) was 51.9% higher than those performed using the single-slice scanner (3896) (p < 0.0006). CONCLUSION: Using a multislice CT scanner leads to an increase in CT productivity, even though multislice studies are performed using more complicated protocols than are used on a single-slice CT scanner.

Efficiency↗
PubMed1991

Structural studies of a polysaccharide isolated from the green seaweed Chaetomorpha anteninna.

Extraction of the green seaweed Chaetomorpha anteninna with water, followed by fractionation using the copper complex, gave a sulphated heteropolysaccharide, [alpha]D27 +84 degrees, that contained arabinose (57.7%), galactose (38.5%), rhamnose (3.8%), and sulphate (11.9%). Application of methylation analysis, periodate oxidation, and partial acid hydrolysis indicated a branched structure with 4-linked arabinose, 4- and 3-linked galactose, and 4-linked rhamnose residues. Both the arabinose and galactose residues carried branches. Desulphation and analysis of the polymeric product showed that sulphate groups were located at C-2 of some of the interior arabinose residues, C-4 of some of the non-reducing-end arabisoyl groups, and C-3 of the non-reducing-end galactosyl groups.

Carbohydrate Conformation↗
PubMed1995

[Spectro-temporal mapping (STM)].

In recent years, various kinds of time-varying spectral analysis which estimate the frequency content of a signal as a function of time have been proposed. Spectro-temporal mapping (STM) is one of such methods with elaborate modification of a simple fixed period analysis. Merits and demerits of this method in clinical application are described in this chapter. Certain technical aspects pertinent to the interpretation of STM were also discussed. In conclusion, STM in present form is inferior to time domain analysis for the prediction of serious ventricular arrhythmias. But it has some usefulness to supplement time domain analysis in noise detection and application to patients with broad QRS complex.

Body Surface Potential Mapping↗
PubMed2005

Intercomparison of the community multiscale air quality model and CALGRID using process analysis.

This study was designed to examine the similarities and differences between two advanced photochemical air quality modeling systems: EPA Models-3/CMAQ and CALGRID/CALMET. Both modeling systems were applied to an ozone episode that occurred along the I-5 urban corridor in western Washington and Oregon during July 11-14, 1996. Both models employed the same modeling domain and used the same detailed gridded emission inventory. The CMAQ model was run using both the CB-IV and RADM2 chemical mechanisms, while CALGRID was used with the SAPRC-97 chemical mechanism. Outputfrom the Mesoscale Meteorological Model (MM5) employed with observational nudging was used in both models. The two modeling systems, representing three chemical mechanisms and two sets of meteorological inputs, were evaluated in terms of statistical performance measures for both 1- and 8-h average observed ozone concentrations. The results showed that the different versions of the systems were more similar than different, and all versions performed well in the Portland region and downwind of Seattle but performed poorly in the more rural region north of Seattle. Improving the meteorological input into the CALGRID/CALMET system with planetary boundary layer (PBL) parameters from the Models-3/CMAQ meteorology preprocessor (MCIP) improved the performance of the CALGRID/CALMET system. The 8-h ensemble case was often the best performer of all the cases indicating that the models perform better over longer analysis periods. The 1-h ensemble case, derived from all runs, was not necessarily an improvement over the five individual cases, but the standard deviation about the mean provided a measure of overall modeling uncertainty. Process analysis was applied to examine the contribution of the individual processes to the species conservation equation. The process analysis results indicated that the two modeling systems arrive at similar solutions by very different means. Transport rates are faster and exhibit greater fluctuations in the CMAQ cases than in the CALGRID cases, which lead to different placement of the urban ozone plumes. The CALGRID cases, which rely on the SAPRC97 chemical mechanism, exhibited a greater diurnal production/loss cycle of ozone concentrations per hour compared to either the RADM2 or CBIV chemical mechanisms in the CMAQ cases. These results demonstrate the need for specialized process field measurements to confirm whether we are modeling ozone with valid processes.

Aerosols↗
PubMed1999

Musical rhythms in heart period dynamics: a cross-cultural and interdisciplinary approach to cardiac rhythms.

The purpose of this study was to expand classic heart period analysis methods by techniques from ethnomusicology that explicitly take complex musical rhythm principles into consideration. The methods used are based on the theory of African music, the theory of symbolic dynamics, and combinatorial theory. Heart period tachograms from 192 24-h electrocardiograms of 96 healthy subjects were transformed into binary symbol sequences that were interpretable as elementary rhythmic (percussive) patterns, the time lines in African music. Using a hierarchical rhythm pattern scheme closely related to the Derler Rhythm Classification (from jazz theory), we calculated the predominance and stability of pattern classes. The results show that during sleep certain classes, specific to individuals, occurred in a cyclically recurrent manner and many times more often than expected. Simultaneously, other classes disappeared more or less completely. Moreover, the most frequent classes obviously originate from phase-locking processes in autonomic regulation (e.g., between respiratory and cardiac cycles). In conclusion, the new interdisciplinary method presented here demonstrates that heart period patterns, in particular those occurring during night sleep, can be interpreted as musical rhythms. This method may be of great potential use in music therapy research.

Adult↗
PubMed1986

The mean platelet volume (MPV) in the neonatal period.

Previous studies in adults have demonstrated that the mean platelet volume (MPV), which is now routinely measured during blood counting performed by the Coulter Counter S Plus, is an important parameter and may serve as a predictor of the hemostatic potential of patients with severe thrombocytopenia. MPVs and platelet counts were determined in 155 neonates in order to establish the normal values of the mean platelet volume during the neonatal period. Analysis of variance performed in 119 neonates of birthweight greater than 2 kg revealed a significant rise with age of both platelet count (P less than 0.0001 and MPV (P less than 0.02) during the neonatal period. The platelet counts of these 119 neonates (323336 +/- 106918; mean +/- SD) were significantly higher (P less than 0.05) than the platelet counts (283805 +/- 114130) of 36 neonates where birthweight was less than 2 kg. There was no significant difference between the MPV values of the two groups (8.67 +/- 1.03 micron3 and 8.89 +/- 1.10 micron3, respectively). Since increased MPV is observed during periods of platelet production, the above results suggest that the rise of platelet count associated with increased MPV in newborn infants is due to increased production of platelets in the early postnatal weeks.

Birth Weight↗
PubMed1992

Distribution of period-analyzed delta activity during sleep.

The distribution of delta EEG activity was evaluated during sleep in eight healthy adults. Digital period analysis, including an amplitude measurement, was used to quantify delta activity. The average percentages of delta half- and full-wave zero-crosses, mean delta power, and mean total power were computed for each nonrapid eye movement (NREM) period. The distribution of these delta measures was examined across NREM periods (NREMPs). No significant linear trends were evident in the zero-cross or power measures. Four subjects showed the highest delta power and greatest incidence of delta in the second rather than first NREMP. Regression analyses of individual delta incidence data revealed that only 62.5% of recording nights could be described with an exponential equation. Exponential regressions described 81% of delta amplitude cases. Further, delta activity in some subjects could be described by either linear or exponential regression. The findings suggest that the temporal changes of delta activity may not be entirely systematic across NREMPs and are variable across subjects.

Adult↗
PubMed2004

External beam radiotherapy for clinically node-negative, localized hormone-refractory prostate cancer: impact of pretreatment PSA value on radiotherapeutic outcomes.

PURPOSE: To analyze the results of clinically node-negative, localized hormone-refractory prostate cancer treated with external beam radiotherapy (EBRT) and to investigate the potential prognostic factors that influenced the therapeutic outcome. METHODS AND MATERIALS: Fifty-three patients who had developed localized hormone-refractory prostate cancer were treated with EBRT between 1994 and 2001. According to the 1992 American Joint Committee on Cancer clinical stage, 4 patients had T2 and 49 had T3 at the start of RT, and 14 patients had a Gleason score <7, 14 had a Gleason score of 7, and 23 had a Gleason score of 8-10. All patients were treated with EBRT using the unblocked oblique four-field technique, with a total dose of 69 Gy. The fraction dose was 3 Gy three times weekly. The median follow-up after RT was 35 months (range, 8-96 months) and after androgen ablation was 73 months (range, 42-156 months). RESULTS: Of 53 patients, 15 patients subsequently developed clinical relapse, including locoregional and/or distant metastases. The site of first relapse was bone metastasis in 10, lymph nodes in 3, and local failure in 2 patients; 3 patients died of prostate cancer during the analysis period. The 3-year and 5-year cause-specific survival rate was 94% and 87%, respectively, and the 3-year and 5-year clinical relapse-free survival rate was 78% and 56%, respectively. The univariate analysis revealed that a short prostate-specific antigen (PSA) doubling time and high PSA value at the start of RT and a high Gleason score were statistically significant factors for the risk of clinical relapse. Multivariate analysis demonstrated that the PSA value (PSA or=15 ng/mL) at the start of RT was an independent prognostic factor. CONCLUSION: EBRT could be a treatment of choice for clinically node-negative, localized, hormone-refractory prostate cancer.

Aged↗
PubMed2005

Comparative study of DNA synthesis and nucleolar organizer regions of sinusoid littoral cells in mouse regenerating liver.

Variations in DNA synthesis (DNAs) and Nucleolar Organizer Regions (NORs) were studied in the littoral cell population from regenerating liver of C3HS inbred mice standardized for periodicity analysis. Immunohistochemical detection of Bromodeoxyuridine (BrdU) with a monoclonal antibody and silver staining of NORs (AgNORs) were assessed by means of a digital image analysis system in histological sections. Tissue samples were obtained every four hours from the 30th to the 54th hours after a partial hepatectomy. The results showed, in both parameters, a gradual increment of the values during the period studied, with highest values (DNAs 107.1 +/- 16.1 SE; AgNORs 77.3 +/- 3.4 SE) located at 16:00/54 Time of Day / Hours Post-Hepatectomy (TD/HPH), which were significantly different (p <0.001) from the values of the first sample (DNAs 38.1 +/- 9.5 SE; AgNORs 27.3 +/- 1.0 SE) taken at 16:00/30 TD/HPH. The results of our experiment demonstrate the existence of a strong correlation of DNA synthesis measured by BrdU immunohistochemistry and AgNORs numbers in sinusoid littoral cells from mouse regenerating liver.

Animals↗
PubMed1997

[Mitotic activity of duodenal-crypt enterocytes in mice with hepatocarcinoma].

Tumors grafted into mice may modify the proliferation of normal cell populations. In this paper, we have studied the evolution of mitotic activity (MA) in duodenal-crypt enterocytes of ES12a hepatocarcinoma-bearing mice; a total of 87 28-day-old female animals of the C3H/S strain were used after standardization for circadian-periodicity analysis. The mice were distributed into two groups: those remaining intact and those receiving tumor grafts. Each group was then divided into six batches (n = 6-10), one of which was sacrificed every 4 h over a period of one day. A dose of colchicine (2 micrograms/g) was administered to each animal 4 h before killing. Samples of duodenum were fixed in 10% (v/v) buffered formalin and processed for assessment of mitotic activity. The number and topographic localization of the colchicine-arrested metaphases were recorded among the entero-cytes within 20 longitudinal sections of the duodenal crypts in each animal. From these data the mitotic indices over the total crypt-cell population as well as within each previously-established zone were determined along with mean +/- SEM for each experimental group. The statistical significance of the differences among the data were analyzed by Student t test. The results show that the presence of ES12a tumor inhibits the mitotic activity of the duodenal-crypt enterocytes and produces an apparent temporal shift in the peak and trough within the circadian curve for this growth parameter.

Animals↗
PubMed1975

Changes in frequency and amplitude of delta activity during sleep.

Modified period analysis was applied to all-night sleep recordings from 14 young adult males. The modifications involved addition of measures of integrated amplitude and of time in frequency band to the zero crossings and zero counts of the first derivative. The analysis was directed toward changes in the characteristics of delta activity (0--3 c/sec) across the night. Delta shifted toward lower frequencies and decreased in amplitude as sleep progressed. These trends were apparent in mean values for successive periods of slow-wave sleep (SSWPs). For epochs of record classified as stage 4 EEG, these trends were seen both within and across SSWPs. The physiological significance of these changes is unknown. We suggest that they may reflect the kinetics of the metabolic processes underlying sleep. Whatever their theoretical significance, the present results provide new, normative features of the sleep EEG which are not evident in sleep stage classification. The trends we observed appear sufficiently reliable to merit empirical investigation as a function of age, clinical state, or the administration of drugs in addition to further studies aimed at determining their biological significance.

Adult↗
PubMed1989

Theophylline disturbs sleep mainly in caffeine-sensitive persons.

In order to study effects of theophylline on sleep, a randomised double-blind cross-over study with slow release theophylline vs. placebo was performed on 13 healthy male volunteers (mean age 24 years), eight of whom were considered caffeine-sensitive and five caffeine-insensitive. A sleep diary was filled in during the entire period. At the end of each 2 week study period a sleep questionnaire was filled in and a sleep recording was conducted. Seven of the eight caffeine-sensitive persons reported that their sleep was disturbed during the theophylline period, while none of the five caffeine-insensitive experienced any difference between the periods. Analysis of the sleep diaries (mean +/- SD) revealed a significant increase in sleep latency (16 +/- 11 vs 4 +/- 7 min) and decrease in sleep efficiency (95 +/- 3 vs 98 +/- 3%) among the caffeine-sensitive persons during the theophylline period compared with the placebo period, while no such difference was found among the caffeine-insensitive. We conclude that theophylline seems to disturb sleep mainly in caffeine-sensitive persons.

Caffeine↗
PubMedDate not supplied

[Inheritance of heading date in crosses of wheat cultivar responsiveness to light intensity].

The inheritance of heading date has been studied in crosses of spring bread wheat cultivars differing in their reaction to various light intensities. The parental cultivars were similar in their Vrn and Ppd gene systems and differed in heading dates. Domination of higher reaction to light intensity has been shown in F1 on duration of "ear emergence-heading" period. Analysis of F2 populations has shown the identity of earliness per se genetic systems in Novosibirskaya 22 and Ordynskaya cultivars. Digenic differences have been revealed for both these cultivars from Tyumenskaya rannyaya cultivar on duration of "ear emergence--heading" period.

Crosses, Genetic↗
PubMed1980

The teichuronic acid from the walls of Bacillus licheniformis A.T.C.C. 9945.

The teichuronic acid of Bacillus licheniformis A.T.C.C. 9945 grown under phosphate limitation was isolated from the cell walls and purified by ion-exchange and Sephadex chromatography. The detailed structure of the polysaccharide was established by methylation analysis, periodate oxidation and partial acid hydrolysis. The polymer is composed of tetrasaccharide repeating units with the structure [GlcA beta(1 leads to 4)GlcA beta(1 leads to 3)GalNAc beta(1 leads to 6)GalNAc alpha(1 leads to 4)n. 13C n.m.r. analysis has confirmed most of the structural features of the polysaccharide and, in particular, the anomeric configurations and linkage positions of substituents. The teichuronic acid from glucose-limited cells was identical with that from cells grown under phosphate limitation.

Bacillus↗
PubMed1992

Comparison of autoregression and fast Fourier transform techniques for power spectral analysis of heart period variability of persons with sudden cardiac arrest before and after therapy to increase heart period variability.

Clinical studies have used two types of analysis of the power spectral estimates of heart period variability: autoregressive and fast Fourier transform techniques. Controversy exists regarding which method is the most valid. The specific aims of this study are: (1) to describe the power spectra of heart period variability before and after an intervention designed to increase heart period variability in persons after sudden cardiac arrest; (2) to compare the integral of power spectral density between autoregressive and fast Fourier transform techniques within low and high-frequency bands; (3) to compare the magnitude of the spectral peak values determined by autoregressive and fast Fourier transform techniques approaches within low and high-frequency bands; and (4) to compare the aforementioned parameters using 4-minute, 1-hour, and 24-hour blocks of heart period data. Results indicated high correlations between spectral estimations by autoregressive and fast Fourier transform techniques using integrals or peak values within either the low or high-frequency ranges. The autoregressive technique demonstrated better resolution of sharp peaks than the fast Fourier transform technique, and makes a smoother, more interpretable curve. Lastly, people can cognitively change their heart rate variability.

Biofeedback, Psychology↗