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PubMed2005

The period length of fibroblast circadian gene expression varies widely among human individuals.

Mammalian circadian behavior is governed by a central clock in the suprachiasmatic nucleus of the brain hypothalamus, and its intrinsic period length is believed to affect the phase of daily activities. Measurement of this period length, normally accomplished by prolonged subject observation, is difficult and costly in humans. Because a circadian clock similar to that of the suprachiasmatic nucleus is present in most cell types, we were able to engineer a lentiviral circadian reporter that permits characterization of circadian rhythms in single skin biopsies. Using it, we have determined the period lengths of 19 human individuals. The average value from all subjects, 24.5 h, closely matches average values for human circadian physiology obtained in studies in which circadian period was assessed in the absence of the confounding effects of light input and sleep-wake cycle feedback. Nevertheless, the distribution of period lengths measured from biopsies from different individuals was wider than those reported for circadian physiology. A similar trend was observed when comparing wheel-running behavior with fibroblast period length in mouse strains containing circadian gene disruptions. In mice, inter-individual differences in fibroblast period length correlated with the period of running-wheel activity; in humans, fibroblasts from different individuals showed widely variant circadian periods. Given its robustness, the presented procedure should permit quantitative trait mapping of human period length.

3T3 Cells↗
PubMed1976

Duration of diestrous period and secretion of progestins during prolonged lactation in the rat.

The duration of the diestrous period in vaginal smears and the levels of progestins in ovarian venous blood were investigated in rats whose lactation period was prolonged by replacing pups at appropriate intervals. In prolonged lactating rats, the first diestrous period after the pospartum ovulation (21.7 +/- 0.8 days) was similar to that occurring in normal lactating rats. Subsequently proestrous or estrous vaginal smears reappeared at intervals during prolonged lactation. A total of 19 rats were studied during this period of prolonged lactation and 44 diestrous periods were observed. Forty-eight % of these periods ranged in length from 11 to 16 days (mean of 12.7). Very short diestrous periods lasting less than 3 days were observed 25% of the time. Diestrous periods lasting more than 17 days were observed only infrequently (7%). Progesterone concentration in the ovarian vein during the 2nd diestrous period reached a peak 4 days after the 1st estrus and the level was maintained until 11 days after the 1st estrus. The level of 20alpha-hydroxypregn-4-en-3-one remained fairly constant throughout the 2nd diestrous period.

Animals↗
PubMed1997

Association of type VI collagen with D-periodic collagen fibrils in developing tail tendons of mice.

The process of the arrangement of D-periodic collagen fibrils and their growth in maturing tail tendon of mice were studied with the association of type VI collagen, from fetal day 10 to 10 weeks after birth. In tail tendons, the amount of collagen fibers gradually increased along with the diameters of D-periodic collagen fibrils during maturation. Type VI collagens first appeared on fetal day 10, when D-periodic collagen fibrils were not recognizable. Type VI collagens were observed around the fibroblastic cells in early stages of development, but were among thick collagen fibrils in the adult tendon. While the periodic distances of type VI collagen fibrils were over 100 nm at fetal days, they were packed to 80-90 nm after birth. The periodic bands were stained well with ruthenium red in adult but not in young tendons, indicating the close association of proteoglycans or glycosaminoglycans (PGs/GAGs) with maturing type VI collagens. Since type VI collagen in native form is known to associate with D-periodic collagen fibrils via PGs/ GAGs, ruthenium red-stainability on the surface of D-periodic collagen fibrils was also examined; results showed that ruthenium red-stainable elements were D-periodically associated. When the surface morphology of D-periodic collagen fibrils in adult animals was examined by atomic force microscopy, a large depth of the groove between elevated and depressed surfaces became prominent when the fibril surface was digested with hyaluronidase. Thus, it is possible to observe topologically the association of PGs/GAGs and probably that of type VI collagens with D-periodic collagen fibrils.

Animals↗
PubMed2002

Technical note: the effect of freezing on Warner-Bratzler shear force values of beef longissimus steaks across several postmortem aging periods.

The objective of this study was to compare fresh and frozen protocol procedures for Warner-Bratzler shear force (WBSF) determination on steaks aged for different periods of time. The fresh protocol consisted of measuring WBSF on steaks cooked on the exact day the aging period ended. The frozen protocol consisted of measuring WBSF on steaks that were aged, frozen (-16 degrees C) for approximately 2 mo, thawed for 24 h, and then cooked. Twenty-two strip loin steaks from each of 20 crossbred heifers and steers were individually vacuum-packaged and assigned to either the fresh or frozen protocol and one of 11 aging periods (1, 2, 3, 4, 5, 6, 7, 10, 14, 21, or 35 d). The frozen protocol resulted in lower (P < 0.05) WBSF values than the fresh protocol for beef longissimus steaks that were aged for 1, 2, 3, 4, 6, 7, 10, 14, or 35 d postmortem. An interaction (P < 0.05) between protocol and postmortem aging resulted from larger differences between protocols at shorter aging periods than at longer aging periods. Correlations and mean differences revealed that frozen protocol WBSF values were not highly indicative of fresh protocol WBSF values at the same period of postmortem aging, but rather suggested that frozen protocol WBSF values at shorter aging times were useful in estimating WBSF values from fresh protocols at longer aging times. Cooking loss was higher (P < 0.05) for frozen vs fresh protocol steaks at all aging periods except for 14, 21, or 35 d. These findings suggest that if research constraints warrant the freezing of samples, shorter aging periods before freezing (6 and 7 d) should be used to estimate WBSF of fresh aged beef (14 to 21 d). In trials in which several postmortem aging periods or very short aging periods are of interest, we recommend that WBSF be assessed using the fresh protocol.

Animals↗
PubMed1994

Preferences regarding treatments for period problems: relationship to menstrual and demographic factors.

Beliefs about periods and hysterectomy and preferences regarding treatment for period problems were assessed in 362 women--patients referred for menorrhagia, premenstrual syndrome, or dysmenorrhea (n = 99, 102 and 56 respectively), and a control sample (n = 105). Overall, women were predominantly in favor of a treatment which normalized periods (89%) and which coincidentally provided reversible contraceptive effect (74%), while they marginally preferred a one-off operation to tablets. Preferences with regard to contraceptive effect of treatment, effect on periods and hypothetical treatment option were most strongly related to reproductive status (p < 0.00002), in that nulliparous or unsterilized women were least likely to rate as acceptable a treatment that affected their periods or fertility. The women's feelings about their periods and their evaluation of the utilitarian consequences of hysterectomy were most strongly related to their report of menstrual problem(s), with the potential benefits of an end to periods being most often affirmed by women reporting 'severe' menorrhagia, dysmenorrhea or multiple period problems. In contrast, women's evaluation of the reproductive consequences of hysterectomy were most strongly related to reproductive status, with nulliparous women and unsterilized parous women finding them least acceptable. Feelings about periods did not predict intentions with respect to periods, or treatment preferences, and in this regard the usefulness of menstrual attitudes is questioned.

Adult↗
PubMed1995

Latent periodicity of DNA sequences from some human gene regions.

The mutual information is used to reveal of DNA sequences latent periodicity. Latent periodicity of DNA sequence is periodic. ity with low level of homology between any two periods inside DNA sequence. The mutual information between artificial numerical sequence and DNA sequence is calculated. The length of artificial sequence period is changed from 2 to 250. High level of mutual information between artificial and DNA sequences allows to find any type of latent periodicity of DNA sequence. The latent periodicity of some DNA coding regions is considered. For example, 24 exon of Apo B-100 gene from HSAP821 clone contains latent period 84 bases long. The IGF-I receptor gene from HSIGFIRR clone contains the region with latent period 57 bases long. Possible significance of latent periodicity is discussed.

Apolipoprotein B-100↗
PubMed1985

Environmental pathogens and intramammary infection during the dry period.

Rate of coliform and streptococcal intramammary infection during the dry period was studied in 168 dry periods. Coliform infection rate was influenced by stage of dry period, parity, and season during which dry periods occurred. Effects of dry cow therapy, immunization, or induced inflammation on coliform infection rate were minimal. Coliform infections originating in the first 50% of the dry period and persisting to lactation were predominantly other than Escherichia coli, whereas the majority originating in the last 50% of the dry period and persisting to lactation were Escherichia coli. Duration of streptococcal infections was greater than coliform infections. Dry cow therapy reduced streptococcal infection rate, and the effect was exerted primarily during the first 25% of the dry period. Effects of parity and season were not significant and likely masked by the positive effects of dry cow therapy. Results support the contention that all quarters of all cows should be dry treated for maximum reduction of new streptococcal infection during the dry period. Results suggest that methods other than conventional dry cow therapy are required for control of coliform infection during the dry period and streptococcal infection during the latter half of the dry period.

Animals↗
PubMed1996

A method for measuring specific antibodies in bovine lacteal secretions during the nonlactating period.

A large portion of new IMI in dairy cattle occurs during the nonlactating period. Because antibiotic infusions at the beginning of the nonlactating period are only partially effective, attempts have been made to stimulate the production of protective antibodies in lacteal secretions during this period. However, measurement of antibodies in mammary secretions during the nonlactating period has been hampered by the complex, viscous nature of these secretions. This report describes the use of caprylic acid to clarify secretions from the bovine mammary gland during the nonlactating period to provide a more accurate measurement of specific antibody. Six healthy Jersey cows were injected in the area of the supramammary lymph node with an encapsulated strain of Staphylococcus aureus in dextran sulfate at the beginning of the nonlactating period and 15 and 30 d later. Seven healthy unimmunized Jersey cows served as controls. Lacteal secretions taken at the beginning of the nonlactating period; at 15, 30, and 45 d into the nonlactating period; and at calving were treated with caprylic acid prior to assay for specific antibodies using ELISA. Purified S. aureus capsule was used as the antigen in the ELISA. Caprylic acid lowered non-specific binding of IgG1 and IgM in secretions during the dry period from unimmunized control cows and lowered IgM from immunized cows. The most pronounced effect of caprylic acid was an increase in IgG2 binding in secretions from immunized cows. Treatment with caprylic acid more accurately measured specific activity of Ig in mammary secretions during the nonlactating period.

Animals↗
PubMed1998

Lymphatics of the rat mammary gland during virgin, pregnant, lactating and post-weaning periods.

The distribution and ultrastructure of the lymphatics of the rat mammary gland in virgin, pregnant, lactating and post-weaning periods were examined by enzyme-histochemistry for 5'-nucleotidase (5'-Nase) and transmission electron microscopy. Enzyme-histochemistry for 5'-Nase stained lymphatics in dark brown. In the lactating period, lymphatics abounded in the interlobular connective tissues, but in other periods they were few. The interlobular lymphatics drained into collecting lymphatics running along the mammary ducts. Gaps between lymphatic endothelial cells were significantly wider in lactating period than in other periods, while both number and area of vesicles in the lymphatic endothelial cells were significantly larger in the virgin period than in other periods. In the pregnant and lactating period, the lymphatics contained many lymphocytes and lipid droplets. The results show that during lactating period, the interlobular lymphatics increase and that gaps between lymphatic endothelial cells serve as a major route through which tissue fluids and particulate matters enter the lymphatics, while vesicles seem to be main trans-endothelial transport route during the virgin period. The results will provide basic information for our next investigation on lymphangiogenesis in association with breast cancer.

5'-Nucleotidase↗
PubMedDate not supplied

A comparison of survival in extremely low birth weight infants between periods 1997-1998 and 1998-2000.

The survival rates and the influential perinatal factors of extremely low birth weight (ELBW) infants were compared between two periods, including January 1997 through May 1998 (Period 1, n = 84) and June 1998 through December 2000 (Period 2, n = 145). The survival rate was 48.8% (41/84) during Period 1 and 55.2% (80/145) during Period 2. Gestational age (GA) and birth weight (BW) were the most important factors that influenced the survival rate. The cut off levels, below which mortality rates increased significantly, were GA < 24 weeks and BW < 700 gm during Period 1 and GA < 24 weeks and BW < 500 gm during Period 2. During Period 1, the smallest survival was a female infant with GA of 23 weeks and BW of 530 gm who had no complication and lived well. During Period 2, the smallest survival was a female infant with GA of 21 weeks and BW of 460 gm who was discharged with home oxygen therapy. She was admitted again via emergency due to sudden onset of apnea and cardiac arrest 4 days after discharge, and she died 4 days after the 2nd admission. Our results did not show any advantages to maternal transfer or delivery by Cesarean section. The early neonatal mortality rate was still high during Period 2 and accounted for 50% of the overall neonatal mortality rate. This implies that further training to improve the neonatal care, especially during the early stage of the first week should be reinforced to reduce neonatal deaths. Prevention of the births of extremely premature infants should be more emphasized to decrease neonatal mortality and morbidity rates. When the delivery of an ELBW infant is impending, an active plan of treatment for all infants of GA > or = 24 weeks or BW > or = 500 gm seems appropriate.

Female↗
PubMed1992

Growth and development of the face in complete unilateral cleft lip and palate during prepubertal and pubertal periods.

Roentgencephalometry was used for the assessment of the growth and development of the face during prepubertal and pubertal periods in children with complete unilateral cleft lip and palate treated with the same methods. The first series included 16 boys and 15 girls, the second series consisted of 15 boys and 15 girls examined repeatedly at the beginning and at the end of the follow-up period. There were no definite differences in the growth rate of the face between the two periods of age. Therefore, the deterioration of overjet during puberty could be due to the depletion of the compensation and adaptation mechanisms after the previous orthodontic treatment rather than to the enhanced growth rate. As compared to other facial dimensions a lower growth rate showed during both periods the length of the anterior base, the depth of the maxilla and in particular the height of the upper lip. Developmental changes of variables of shape and position proceeded similarly during both periods of age. An exception represented the rotation of the mandible and the inclination of upper incisors. During the prepubertal period the lower jaw showed a very slight posterior rotation, while during puberty an anterior growth rotation was present. A rapid improvement of the proclination of upper incisors was attained only during the prepubertal period. It was accompanied by an improvement of overjet. However, during the period of puberty there was a renewed deterioration of overjet. A marked retrusion of the maxilla developed already in the prepubertal period. During both periods occurred an identical impairment of sagittal jaw relations and of the upper lip prominence, accompanied by a flattening of the facial profile and reduction of the nasolabial angle. The prominence of the nose increased, the angle of the cranial base remained unchanged. Intersexual differences were not demonstrated in any studied characteristics.

Adolescent↗
PubMed2003

[A comparative study on severity of tuberculosis cases between those found by periodical chest X-ray examination and those found by symptomatic visit to OPD in Japan].

BACKGROUND: Japanese national tuberculosis control program (NTP) has included indiscriminate chest X-ray examination for adult population. METHODS: A comparative study on the severity of pulmonary tuberculosis cases in a hospital in Tokyo by the mode of detection (between cases found by periodical check and cases found by symptomatic visit) and previous history of X-ray examination (among cases detected by periodical check, cases detected by symptomatic visit but with previous history of periodical check and cases without history of chest X-ray examination during the past 3 years). RESULTS: The comparison between patients found by symptomatic visit with and without previous history of periodical check showed that there was no difference in the grade of sputum smear positivity at the time of diagnosis but that those without previous history of periodical check were more serious as to chest X-ray findings. The comparison between patients found by symptomatic visit with previous history of periodical check and those detected by the periodical check showed that the grade of smear positivity was less among those found by the periodical check but no difference as to chest X-ray findings, however, comparing cases of these two categories in the age group of 40-59, those detected by the periodical check were less serious as to both X-ray findings and smear result. There were 21 persons who were indicated requiring further investigation but actually were not examined. The severity of tuberculosis among these 21 persons were more serious as to the grade of smear positivity than those detected by periodical X-ray examination.

Adult↗
PubMed2003

[Investigative evaluation of mass screening for cancer of the cervix uteri by automobile in two periods (1974-1983 and 1984-1993) in Fukui Prefecture].

OBJECTIVE: The study was carried out to analyse and compare the number of examinees, cancer detection rate change in the age distribution of screened women with data from the periods 1974-1983 and 1984-1993. SUBJECTS AND METHODS: The target population of the study composed women participating in uterine cancer screening by automobile in Fukui prefecture over the twenty year from 1974 to 1993, divided equally into early and late periods. The examination method was smear sampling for cytology, performed by scraping the cervix with a cotton swab or wooden spatula. Patients with suspicious or positive smears underwent histological diagnosis by colposcopic biopsy. RESULTS: 1) The number of examinees was increased over 160% during the late as compared to the early periods. 2) The dysplasia detection rate increased from 0.195 to 0.27%. 3) The carcinoma detection rate, in contrast, decreased from 0.2% to 0.1%. 4) The rate of smears categorized as class III or above increased with age in the early period but was steady across the age distribution in the late period. 5) Class (IIIa) dysplasia and class (IIIb) in situ carcinoma detection rates were higher in the late than the early period. 6) The carcinoma detection rates increased with age in early period, while in the late period, those for patients under the age of 29 and over 70 years old were higher and these for other ages were lower than in the early period. 7) The carcinoma detection rate for first examinees was higher than for repeated examinees. 8) The proportion of first examinees was 65.5% among women under the age of 29 and 46.8% among women aged 30-34. 9) Carcinoma detection rates for individual public health centers (PHCs) were Fukui PHC 0.13%, Kanazu PHC 0.11%, Okuetsu PHC 0.09%, Tannan PHC 0.11%, Reinan PHC 0.04%. CONCLUSIONS: The results showed the detection rate to be higher at the first visit. The detection rates for dysplasia and carcinoma were increased in young women in the late as compared to the early period. It is important to follow up the patients with dysplasia and encourage more frequent visit by young as well as aged women.

Adult↗
PubMedDate not supplied

Isolation period prediction in patients with differentiated thyroid carcinoma treated after thyroidectomy by radioiodine-131.

In patients with differentiated thyroid carcinoma (DTC) who after thyroidectomy underwent radioiodine-131 ((131)I) treatment for the ablation of the thyroid remnant, isolation period is considered as the period of time needed for patients' radiation dose rates to be reduced below specific adopted dose rate release limits. The aim of our study was to determine mathematical equations for the prediction of the isolation period in these patients and of their discharge from special isolation rooms in nuclear medicine departments. In order, to predict the duration of the isolation period, we studied twenty-eight patients with DTC and total thyroidectomy having no metastases, who underwent (131)I ablation treatment for a minimal residual thyroid remnant. The administered (131)I activity was 5.22 +/- 0.68 GBq, ranging from 3.66 to 6.21 GBq. Dose rates, as mean +/- SD, at a distance of 1 m from the patients were 277 +/- 44 microSv/h, immediately after (131)I administration, 72 +/- 18 microSv/h at 24 h and 23 +/- 9 microSv/h at 48 h. Whole body (131)I retention was 0.261 +/- 0.05 (range 0.168-0.385) at 24 h and 0.082 +/- 0.03 (range 0.041-0.149) at 48 h, calculated as the ratio of dose rate at 24 h and 48 h versus the initial dose rate after (131)I administration. Isolation period was calculated by a mono-exponential fitting in dose rate decay data according specific dose rate release limits. For a dose rate release limit of 30 microSv/h at 1 m, isolation period was 42.7+/-7.2 h (range 31.2-56.6 h). Seventy-five percent of the patients satisfied this limit within 48 h and 25% between 48 h and 72 h. This isolation period was positively correlated with the whole body (131)I retention and the dose rates at 24 h and 48 h, but not always with the administered activity or the initial dose rate, measured immediately after (131)I administration. On the contrary, a strong negative correlation was found between patients' isolation period and dose rate release limits between 3 and 60 microSv/h at 1 m. This study indicates that isolation period is variable but can be predicted by multiple formulas, since it depends strongly on the adopted dose rate release limits, (131)I dose rates and whole body retention at 24 h and 48 h after (131)I treatment. For a dose rate release limit of 30 microSv/h at 1 m, isolation period is sufficient for 72 h for all of our patients, while 75% of them had dose rates below that limit within 48 h.

Journal Article↗
PubMedDate not supplied

Postpubertal growth and development of the face in unilateral cleft lip and palate as compared to the pubertal period: a longitudinal study.

X-ray cephalometry was used for the assessment of 22 boys and 23 girls with complete unilateral cleft lip and palate who were treated with the same surgical method. They were examined at the age of 10 years and in adulthood. In the group of 13 boys and 15 girls, examined also at the age of 15 years, were analysed intersexual differences of facial growth and development during the postpubertal period and the results were compared with those obtained during the pubertal period. The data showed that in boys facial growth persists after the age of 15 years and in the region of the upper face attains about half the values recorded in the period of puberty, while mandibular growth attains almost the same values as during puberty. In girls the growth is almost terminated but for the lower jaw, where it is still significant though several times slighter than during puberty. In both sexes there is only a minimum growth of maxillary depth and of upper lip height during the postpubertal period, as well as during the pubertal period. The highest growth rate shows the depth of the nose. Because of the intersexual differences in the amount of postpubertal growth, developmental changes in facial configuration do not occur in girls during this period, while in boys a further deterioration of maxillary protrusion, of sagittal jaw relations, and of the upper lip prominence continues, as well as an increase of the flattening of the face. In contrast to the pubertal period in both sexes, a proclination of upper incisors and an improvement of overjet was not attained. Contrary to the pubertal period, in the postpubertal period, intersexual differences in the amount of growth and of the developmental changes in the shape and position of facial characteristics were recorded. Therefore during studies of the growth and development of the face, it is not possible to pool both sexes without some reservations. This holds true in particular in the postpubertal period.

Adolescent↗
PubMedDate not supplied

Right ventricular systolic sub-periods. Normal values.

Right ventricular systolic sub-periods were examined in the group of 18 healthy subjects, basing on simultaneous electrocardiographic, phonocardiographic and pulmonary artery pressure tracings. The values established were compared with corresponding left ventricular systolic periods and correlated with selected hemodynamic parameters. Following mean values of the right ventricular systolic sub-periods were found: Q -- 1. sound interval = 0.051 sec., systolic time = 0.404 sec., ejection period = 0.319 sec., pre-ejection period = 0.085 sec., and isovolumetric contraction time = 0.034 sec. Both the right ventricular systolic and ejection periods were significantly longer than the corresponding left ventricular systolic ones. The ratio: right ventricular pre-ejection period to ejection period was lower than that calculated for the left ventricle. Both the right ventricular systolic and ejection periods negatively correlated with heart rate, whereas the ratio: right ventricular isovolumetric contraction time to ejection period depended on pulmonary artery pressure, pulmonary resistance and right ventricular work index.

Adolescent↗
PubMed2004

[Methods and clinical value of peripheral nerve refractory period measurement in man].

Immediately after action potential occurrence, owing to transient sodium channel inactivation, axon excitability is reduced for a short period of time, including the absolute refractory period, a first period of total inexcitability, followed by the relative refractory period. There are basically two different stimulation protocols to estimate axonal refractoriness, i.e. "paired-pulse" and "collision" techniques. Refractory period has been assessed in various conditions and appeared to depend on several physiological or methodological factors, featuring the type of nerve or the characteristics of the subject, but also the technique of stimulation or the method of data analysis. In addition, refractory periods can be altered by pathological conditions. Several studies showed prolonged refractory periods in patients suffering from alcoholic, diabetic or toxic neuropathies. Refractory period abnormality is a sensitive marker of axonal dysfunction as observed in Guillain-Barré syndrome, carpal tunnel syndrome or multiple sclerosis. Thus, the measurement of the refractory periods is a valuable tool to study the pathophysiology of peripheral nerves, complementary to standard nerve conduction studies. However, the application of these techniques in the routine practice of clinical neurophysiology remains limited.

Adult↗
PubMed1989

Frequency specificity in intercellular communication. Influence of patterns of periodic signaling on target cell responsiveness.

Cells often communicate by means of periodic signals, as exemplified by a large number of hormones and by the aggregation of Dictyostelium discoideum amebas in response to periodic pulses of cyclic AMP. Periodic signaling allows bypassing the phenomenon of desensitization brought about by constant stimuli. To gain further insight into the efficiency of pulsatile signaling, we analyze the effect of periodic stimulation on the dynamic behavior of a receptor system capable of desensitization toward its ligand. We first show that the receptor system adapts to square-wave stimuli, i.e., the response eventually reaches a steady, periodic pattern after a transient phase. By analyzing the dependence of the response on the characteristics of the square-wave stimulation, we show that there exist a waveform and a period of that signal that result in maximum responsiveness of the target system. Similar results are obtained when the signal takes the more realistic form of a periodically repeated stimulation followed by exponential decay of the ligand. The results are discussed with respect to the role of pulsatile secretion of gonadotropin-releasing hormone (GnRH) by the hypothalamus and of periodic signaling by cyclic AMP pulses in Dictyostelium. The analysis accounts for the existence, in both cases, of an optimal frequency and waveform of the periodic stimulus that correspond to maximum target cell responsiveness.

Animals↗