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PubMed1994

Periodic health examination, 1994 update: 4. Secondary prevention of elder abuse and mistreatment. Canadian Task Force on the Periodic Health Examination.

OBJECTIVE: To provide recommendations for family physicians on the detection, assessment and management of abuse or mistreatment in patients over 65 years of age. OPTIONS: Detection of elder abuse by history and examination or by specific protocols; intervention through mandatory reporting, removing the victim from the situation or acting as an advocate for the patient. OUTCOMES: Termination of abusive situation and prevention of further abuse. EVIDENCE: A MEDLINE search was conducted with the use of medical subject headings "elder abuse" and "epidemiology" for articles published from January 1980 to October 1992 and headings "elder abuse" and "clinical trials" for articles published from January 1980 to February 1994. Standard references and review articles and their bibliographies were scrutinized, and experts were consulted. VALUES: The evidence-based methods and values of the Canadian Task Force on the Periodic Health Examination were used. Since senior citizens are among the most disadvantaged people in Canadian society, prevention of abuse and promotion of their autonomy were the highest values selected. BENEFITS, HARMS AND COSTS: The principal benefits are cessation and prevention of abuse. Potential harms include the loss of a personal residence, the erosion of an established family structure and the loss of autonomy for the victim. RECOMMENDATIONS: There is poor evidence to include case finding for elder abuse in or exclude it from the periodic health examination. However, it is prudent for physicians to be alert for indications of elder abuse and, if such abuse is discovered, to take measures to prevent further abuse.

Aged↗
PubMed1975

[Active period of genes during Drosophila ontogenesis. I. Temperature-sensitive period for the spineless effect in aristapedia mutants].

The temperature-sensitive period (TSP) was determined for the spineless effect (bristle shortening) in SSa40a mutant of Drosophila melanogaster. The length of front orbital and front vertical bristles was measured at different intervals after the temperature shift from 29 to 17 degrees and vice versa. The TSP was found to last from 7 to 14 hrs during pupal development. This corresponds to the activity of the spineless-aristapedia locus during the period of isolation of bristle initial cells. The discordance between the TSP of spineless effect and that of homoeotic effect of the same gene suggests that the locus SSa40a is activated twice during development.

Alleles↗
PubMed1996

Periodic health examination, 1996 update: 1. Prenatal screening for and diagnosis of Down syndrome. Canadian Task Force on the Periodic Health Examination.

OBJECTIVE: To make recommendations to physicians providing prenatal care on (1) whether prenatal screening for and diagnosis of Down syndrome (DS) is advisable and (2) alternative screening and diagnosis manoeuvres. OPTIONS: "Triple-marker" screening of maternal serum levels of alpha-fetoprotein, human chorionic gonadotropin and unconjugated estriol; fetal ultrasonographic examination; amniocentesis; and chorionic villus sampling (CVS). OUTCOMES: Accuracy of detection of DS in fetuses, and risks to the mother, including psychologic distress, and to the fetus from the screening and diagnostic interventions. EVIDENCE: A MEDLINE search for relevant articles published from Jan. 1, 1966, to Mar. 31, 1994, with the use of MeSH terms "Down syndrome," "prenatal diagnosis," "screening," "prevention," "amniocentesis," "chorionic villus sampling," "ultrasonography," "anxiety," "depression" and "psychological stress" and a manual search of bibliographies, recent issues of key journals and Current Contents. VALUES: The evidence-based methods and values of the Canadian Task Force on the Periodic Health Examination were used. A high value was placed on providing pregnant women with the opportunity to determine whether they are carrying a fetus with DS and to make choices concerning the termination of the pregnancy. The economic issues involved are complex and were not considered. BENEFITS, HARMS AND COSTS: Triple-marker screening identifies an estimated 58% of fetuses with DS, but it has an estimated rate of true-positive results of 0.1% and of false-positive results of 3.7% (given a risk cut-off of one chance in 190 of DS). These rates vary with maternal age and the risk cut-off chosen. Women with a known risk of having a fetus with DS (e.g., those who have had a previous child with DS) may benefit from a reduction in anxiety after confirmation that their fetus does not have DS. Screening allows women at low risk of having a child with DS to detect fetuses with the syndrome, but may cause psychologic distress if there is a false-positive screening test result. Up to 20% of women with positive results of screening tests may decline to undergo a subsequent amniocentesis. Amniocentesis and CVS are very accurate in diagnosing DS in fetuses and have a very low rate of serious complications for the mother. Amniocentesis is associated with a 1.7% rate of fetal loss when it is performed after 16 weeks' gestation, whereas the rate among controls is 0.7% (for a difference of 1%, 95% confidence interval 0.3% to 1.5%). CVS entails a greater risk of fetal loss than amniocentesis (odds ratio 1.32, 95% confidence interval 1.11 to 1.57). There is little evidence from controlled trials of significant associations between amniocentesis or CVS and neonatal morbidity or malformations; however, samples have been too small to show differences in rare outcomes. Results from some case-control studies suggest that CVS increases the risk of transverse limb deficiency. Costs were not considered because they are beyond the scope of this review. RECOMMENDATIONS: There is fair evidence to offer triple-marker screening through a comprehensive program to pregnant women under 35 years of age (grade B recommendation). Women given detailed information about serum-marker screening show more satisfaction with the screening than those not given this information. There is fair evidence to offer amniocentesis or CVS to pregnant women 35 years of age and older and to women with a history of a fetus with DS or of a chromosome 21 anomaly (grade B recommendation). Information on the limitations and advantages of each procedure should be offered. Triple-marker screening may be offered as an alternative to CVS or amniocentesis to pregnant women over 35. VALIDATION: Recommendations concerning prenatal diagnosis are similar to those of the US Preventive Services Task Force, the Society of Obstetricians and Gynaecologists of Canada, the Canadian College of Medical Geneticists and the Cochrane Pregnancy and Childbirth Group. No previous specific recommendations concerning triple-maker screening exist. SPONSORS: These guidelines were developed and endorsed by the Canadian Task Force on the Periodic Health Examination, which is funded by Health Canada and the National Health Research and Development Program.

Abortion, Eugenic↗
PubMed1994

Constitutive overexpression of the Drosophila period protein inhibits period mRNA cycling.

The Drosophila period gene (per) is a likely component of a circadian pacemaker. per protein (PER) participates in the regulation of its own expression, at least in part at the transcriptional level. There is at present no direct evidence that the effect of PER on its own transcription is intracellular. Results presented in this paper show that (i) the circadian oscillations of both per mRNA and PER protein are quantitatively similar in eye photoreceptor cells and in brain; (ii) constitutive overexpression of PER only in photoreceptors R1-R6 represses endogenous per RNA cycling in these cells but not in other per-expressing cells; (iii) the overexpression construct has no effect on locomotor activity rhythms. These results indicate that the autoregulation of per expression is a direct, intracellular event and suggest that each per-expressing cell contains an autonomous oscillator of which the per feedback loop is a component.

Animals↗
PubMed1986

Periodate oxidation of glycolipids: a borohydride-periodate-Schiff method for ganglioside demonstration in tissue sections.

Among lipids, gangliosides can be selectively stained with Schiff's reagent if the oxidizing agent (sodium metaperiodate) is sufficiently dilute to exclude all but the readily oxidized sialic acid sugars. A borohydride-periodate-Schiff (BhPS) sequence is recommended as a reliable method, convenient to perform, for the detection of the intraneuronal lipid accumulations in the ganglioside storage disorders.

Borohydrides↗
PubMed1991

The strength and periodicity of D. melanogaster circadian rhythms are differentially affected by alterations in period gene expression.

The per gene of D. melanogaster influences or participates in the generation of biological rhythms. Previous experiments have identified the head as the location from which per exerts its effect on circadian rhythms. To localize further this region and to examine the effects of altered levels and altered spatial expression patterns of the per gene on circadian rhythms of locomotor activity, we have characterized transformed lines containing per gene constructs missing substantial cis-acting regulatory information. The data suggest that wild-type levels of per gene expression are necessary in only a small fraction of the nervous system for near wild-type periods, whereas a larger fraction of per-expressing cells in the brain contributes to the strength of the circadian rhythms.

Animals↗
PubMed2000

Circadian expression of period 1, period 2, and arylalkylamine N-acetyltransferase mRNA in the rat pineal gland under different light conditions.

Period 1 (Per1), 2 (Per2) and arylalkylamine N-acetyltransferase (AA-NAT) mRNA levels were determined by semi-quantitative in situ hybridization in rat pineal glands. In agreement with previous reports, AA-NAT mRNA levels were rhythmic in light:dark (LD) cycles and the rhythm persisted in constant dim light (DLL). Per1 and Per2 mRNA also showed significant variations both in LD and DLL. AA-NAT and Per1 mRNA levels showed very similar patterns of variations in LD and DLL to one another, whereas Per2 showed a different pattern of expression from AA-NAT and Per1. Exposure to 30 min of light did not affect the expression of the three genes, while exposure to a longer light pulse (1 or 2 h) decreased AA-NAT and Per1 mRNA levels; Per2 mRNA levels were also decreased but only temporarily. Our results demonstrate that Per1 and Per2 expression in the rat pineal is under circadian control, and suggest Per1 may be regulated by the same mechanism which controls the expression of AA-NAT gene. Per2 seem to be controlled by a different mechanism.

Animals↗
PubMed2003

Time course of arousal response during periodic leg movements in patients with periodic leg movements and restless legs syndrome.

OBJECTIVE: The temporal evolution of periodic leg movements (PLM) and the relationship of their arousing effect on sleep episode has not been extensively investigated. We studied the nocturnal evolution of PLM associated or not with microarousal (MA) and associated with slow wave activity (PLM with slow wave activity) in 23 patients with PLM and/or restless legs syndrome (RLS). METHODS: All subjects had PLM associated with MA or with slow wave activity as well as without MA and all slept for 4 sleep cycles. Spectral electroencephalogrpahic (EEG) analysis was done for the 4 sleep cycles to assess the nocturnal variation in slow wave activity (SWA). RESULTS: Sixty percent of PLM were associated with MA, 4% were associated with slow wave activity whereas 36% showed no EEG changes. There was a clear prevalence of PLM with MA in stages 1 and 2 while PLM without MA were prevalent in slow wave sleep. The night-time PLM index progressively declined from the first to the last sleep cycle (P<0.005), without differences between PLM types, or between PLM and RLS patients. The decline of PLM duplicated the temporal trend in SWA over consecutive sleep cycles. CONCLUSIONS: PLM showed a typical pattern of progressive decline throughout the night following the exponential decline in SWA. These over-time variations occurred independently of changes in the rate of PLM associated or not with MA or associated with slow wave activity, suggesting that variations in arousal threshold and sleep propensity did not affect the PLM arousing effect. The PLM-related arousal response might be affected by interaction of circadian and sleep stage influences with the addition of sleep oscillatory processes.

Adult↗
PubMed2004

Rats free to select between pure protein and a fat-carbohydrate mix ingest high-protein mixed meals during the dark period and protein meals during the light period.

Rats that are allowed to select their diets [dietary self- selection (DSS)] often ingest >30% of their daily energy in the form of protein. Such an intake may seem unhealthy, but the consistency of this choice suggests that it is motivated by physiologic drives. To gain a clearer understanding of how protein selection is structured during DSS, we adapted 12 rats to a standard diet (14% Protein) and then allowed them to choose between two diets, i.e., total milk protein (P) and a mix of carbohydrates and lipids (FC). The protein intake during DSS rose above 40%; assuming an intermeal interval of 10 min, 70% of the energy intake occurred with meals that included both P and FC, with the sequence of FC followed by P preferred to the sequence of P followed by FC (70 vs. 30%, P < 0.001). In addition, energy intake during the light period was reduced to only 10% of the daily energy intake [vs. 30% with the control P14 diet or a with a high-protein diet (50%)], and 90% of the intake was in the form of pure protein meals. In complementary studies, we verified that the high protein intake also occurred when rats were offered casein and whey and was not due to the high palatability of the milk protein. We conclude that a specific feeding pattern accompanies high protein intake in rats allowed DSS. The mechanisms underlying this behavior and its potential beneficial/adverse consequences over the long term still must be clarified.

Animals↗
PubMed1983

Periodic and non-periodic sleep apnea in premature and fullterm infants.

The sleep states of nine premature infants were observed and concomitant respiration recordings were obtained at 37 and 41 weeks conceptional age. 19 fullterm infants were also studied at 41 weeks conceptional age. Between 37 and 41 weeks significant decreases occurred in the premature infants' percentage of periodic apnea, rate of apnea in active sleep-REM, and length of the longest apneic episode. The premature and fullterm infants at 41 weeks did not differ in the frequency of apneic episodes, but the premature group had shorter episodes. These results provide additional evidence for the difference between premature and fullterm infants in central nervous system organization.

Age Factors↗
PubMed1979

Responses of visual cortical cells to periodic and non-periodic stimuli.

1. The activity of neurones of the visual cortex (area 17) has been recorded in anaesthetized cats in response to gratings of different profile and to single light and dark bars. 2. At very low spatial frequencies, outside the frequency response range to sinusoidal gratings, the response to square-wave drifting gratings is obtainable from a combination of the response to the single bars of the grating presented in isolation. At higher spatial frequencies this is no longer true. 3. At very low spatial frequencies the responses to square-wave gratings and to missing-fundamental gratings (obtained by subtraction from the square-wave grating of its fundamental gratings (obtained by subtraction from the square-wave grating of its fundamental harmonic) are very similar. 4. At spatial frequencies near the peak of the spatial frequency tuning curve of the cell, the responses to square-wave grating and to sinusoidal gratings are very similar. At these spatial frequencies the response to the missing-fundamental grating is practically zero. 5. At spatial frequencies lower than that of best sensitivity for the cell, the response to square-wave gratings is correlated with the 1st and 3rd harmonic of the stimulus. 6. We conclude that at very low spatial frequencies of the grating the response of cortical cells is correlated with the light or dark edges (or light or dark bars) of the stimulus, because the edges contain high frequencies within the range of sensitivity of the cells. At higher spatial frequencies the results are interpreted best by assuming that cortical cells respond to the harmonics of the visual periodic stimulus. 7. When a background of dynamic visual noise is added to increase the spontaneous discharge of simple cells, their response to visual stimuli becomes linear or quasi-linear. The stimuli could be either single bars or gratings.

Action Potentials↗
PubMed1991

Pseudoreflux syndrome-increased periodic breathing during the neonatal period presenting as feeding-related difficulties.

Sixteen infants who presented with symptoms suggestive of gastroesophageal reflux (GER)-associated apnea were evaluated at the Breathing Disorder Center of the Children's Hospital of Philadelphia. These neonates had a history of occasional emesis and an apparent life-threatening event (ALTE) that occurred while awake which was similar to the presentation of a group of infants previously described. Evaluation of the present group of infants however, revealed increased periodic breathing (12.1 +/- 1.8 SEM% of total sleep time) as opposed to the obstructive apnea that was typically seen with GER. Pathologic gastroesophageal reflux could not be diagnosed in relationship to apneic events. Infants who present during the first month of life with symptoms suggestive of GER-associated apnea should have careful evaluation of reflux and respiratory patterns to confirm the correct diagnosis. Because of the similarities of these infants to the GER group, we have called their disorder pseudoreflux.

Diagnosis, Differential↗
PubMed1976

Periodic remission in Cushing's disease with paradoxical dexamethasone response: an expression of periodic hormonogenesis.

A patient with Cushing's disease due to a chromophobe adenoma was studied for 243 days before pituitary surgery and evidence for periodicity in cortisol steroid production was found with cycles occurring every 85.8 days (peak-to-peak length), associated with laboratory remissions and paradoxical response to dexamethasone. The autonomy of ACTH secretion was suggested by the nonresponsiveness to repeated lysine-vasopressin stimulation tests and lack of increase in urinary 170HCS following metyrapone. A distinct response of the hyperplastic glands (as demonstrated by percutaneous adrenal venography) was obtained on several B1-24 corticotropin stimulation. The patient's hypercortisolism disappeared following removal of the chromophobe adenoma through transphenoidal hypophysectomy.

17-Hydroxycorticosteroids↗
PubMed1979

Periodate oxidation analysis of carbohydrates. XIII. Simultaneous gas chromatographic determination of the aldehydes in the periodate oxidation products of non-dialyzable urinary carbohydrate materials as diethyl dithioacetals.

The aldehydes in the periodate oxidation products of non-dialyzable urinary carbohydrate materials were determined simultaneously by gas chromatography of their diethyl dithioacetal derivatives. The yields of aldehydes for normal male urine varied considerably among subjects, but their molar ratios were almost constant. The average values for glyceraldehyde/glyoxal and lactaldehyde/glyoxal molar ratios were 0.41 and 0.27, respectively. The average amount of L-fucose at the non-reducing terminals of carbohydrate chains, as estimated from the yield of lactaldehyde, was about 5 mg/day.

Aldehydes↗
PubMed1987

Periodic gallbladder contraction maintains bile acid circulation during the fasting period: a canine study.

Using a canine model we have studied the relationship between the interdigestive cycle in the small intestine, motility changes in the biliary tract and bile acid output into the duodenum from direct hepatic secretion and gallbladder emptying. Under anaesthesia catheters were inserted into the gallbladder, common bile duct and duodenum, and electrodes were attached to the small intestine in five dogs. These animals were subsequently studied conscious and fasting. A double marker technique was used to measure bile acid output from the gallbladder and liver while pressure in the gallbladder and common bile duct and electrical activity in the small intestine were monitored. Four complete interdigestive cycles were recorded in each dog. Output of bile acids from the gallbladder fluctuated with the phases of the cycle: being lowest in phase I (3.9 +/- 0.7 mumol/min); increasing significantly (P less than 0.005) in phase II (9.8 +/- 1.0 mumol/min); remaining elevated in phase III (13.9 +/- 1.7 mumol/min); and falling significantly (P less than 0.05) in phase IV (8.4 +/- 1.8 mumol/min). In contrast, hepatic secretion of bile acids directly into the duodenum remained fairly constant. Intraluminal pressure in the biliary tract paralleled the fluctuation in gallbladder bile acid output, being significantly increased (P less than 0.05) in phases II and III. Periodic contraction of the gallbladder would, therefore, appear to be the principal mechanism for the phasic output of bile during fasting.

Animals↗
PubMed1993

Digital period analysis of EEG in depression: periodicity, coherence, and interhemispheric relationships during sleep.

1. Interhemispheric EEG differences were compared between 12 symptomatic depressed outpatients, 12 asymptomatic patients and 12 normal controls during two consecutive nights in the Sleep Study Unit. 2. EEG was quantified using digital period analysis (DPA), a time-domain analysis of successive polarity changes (zero-cross) and instances of zero slope (first derivative), yielding percent-time in each frequency band. 3. The degree of hemispheric asymmetry (L-R) was computed for delta, beta and theta percentages from REM, Stage 2 and Slow-Wave (SW) sleep. 4. Normals showed small asymmetries throughout sleep with largest differences in SW, with no consistent relationship between right and left activity and sleep stage. 5. Both depressed groups showed largest asymmetries in REM sleep, with significantly more beta, theta and delta in the right hemisphere consistently. None of the 24 depressed patients showed greater left hemisphere activity throughout sleep.

Adult↗
PubMed1998

Definition of the potentially fertile period from urinary steroid excretion rates. Part II. A threshold value for pregnanediol glucuronide as a marker for the end of the potentially fertile period in the human menstrual cycle.

Application of time series analysis to a database containing serial pregnanediol data from 113 complete ovulatory menstrual cycles contributed by 83 women of proven fertility and 68 cycles for which pregnanediol values were available over the ovulatory period, detected the first statistically significant risk in pregnanediol excretion for all cycles for which a baseline was available (n = 170). However, even at the 99% confidence level, for 22% of cycles a rise was observed before the presumed day of ovulation. Therefore, a threshold value for pregnanediol was sought from the database as a better marker for the end of fertility. A value of 1.4 mg per 24 h was not reached before day 2 after the pre-ovulatory estrogen peak day for 96% of the cycles. In the remaining 4% of cycles it was reached one day after the total estrogen peak day. The validity of this threshold was confirmed in extensive studies using the Ovarian Monitor where the equivalent is 6.3 mumol per 24 h of pregnanediol glucuronide and measurements are performed on timed urine specimens with a minimum collection time of three hours. These studies were as follows: 1) a World Health Organization study on the use of the Ovarian Monitor as a fertility self test in the home (108 cycles), 2) a multicenter study on returning fertility during breast feeding conducted by Family Health International (73 women), and 3) the general application of the Ovarian Monitor for pregnancy achievement and avoidance during the past ten years (over 250,000 PdG assays performed in ten countries). With rare exceptions, the use of these threshold values is applicable for all women provided correction is made for urine volume.

Biomarkers↗
PubMed2006

Bicalutamide 150 mg in addition to standard care for patients with early non-metastatic prostate cancer: updated results from the Scandinavian Prostate Cancer Period Group-6 Study after a median follow-up period of 7.1 years.

OBJECTIVE: The Early Prostate Cancer (EPC) programme is evaluating the efficacy and tolerability of bicalutamide following standard care (radiotherapy, radical prostatectomy or watchful waiting) in patients with localized (T1-2, N0/Nx) or locally advanced (T3-4, any N; or any T, N + ) non-metastatic prostate cancer. Herein we report the latest findings after a median follow-up period of 7.1 years from the Scandinavian Prostate Cancer Group (SPCG)-6 study, one of three trials in the EPC programme. MATERIAL AND METHODS: A total of 1218 patients were randomized on a 1:1 basis to either bicalutamide 150 mg/day (n=607) or placebo (n=611) following standard care; 81.4% were followed conservatively (watchful waiting). The primary endpoints were objective progression-free survival (PFS) and overall survival (OS). RESULTS: In patients with localized disease there was no significant difference in PFS [hazard ratio (HR) 0.85; 95% CI 0.69-1.06; p=0.15] and a trend towards decreased OS with bicalutamide plus standard care compared with standard care alone (HR 1.23; 95% CI 0.96-1.58; p=0.11). In patients with locally advanced disease, bicalutamide significantly improved PFS, reducing the risk of progression by 53% compared with standard care alone (HR 0.47; 95% CI 0.37-0.59; p<0.001). The median time to progression was 8.8 years for bicalutamide plus standard care and 7.1 years for standard care alone. There was a significant improvement in OS with bicalutamide plus standard care, with a reduction in the risk of death of 35% versus standard care alone (HR 0.65; 95% CI 0.50-0.85; p=0.001). CONCLUSION: This analysis of the SPCG-6 study showed that bicalutamide plus standard care offers significant PFS and OS benefits for patients with locally advanced disease, but not for those with localized disease.

Aged↗