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PubMed1993

Effects of shooting period, times within shooting periods and processing systems on the extract, caffeine and crude fiber contents of black tea.

The extract, caffeine and crude fibre contents of black tea, from different shooting periods, different times within each shooting period and processed by five different commercial rolling methods, were examined. The extract and crude fibre contents of black tea were significantly (P < 0.01) affected by all these factors and their interactions. The caffeine content of black tea was affected by the shooting period and times within the shooting period. It was determined that processing methods did not have a significant (P < 0.05) effect on the caffeine content. The amount of extract and caffeine decreased from the first shooting period to the third, and also from the beginning of each shooting period to the end. However, the crude fibre content of the black tea increased, especially from the beginning of each shooting period to the end of each shooting period.

Analysis of Variance↗
PubMed1981

The association of periodic alternating nystagmus with periodic alternating gaze. A case report.

A 26-year-old man with a recurrent cerebellar medulloblastoma developed periodic alternating nystagmus. During radiation treatment, a bilateral voluntary horizontal gaze paresis appeared, and the periodic alternating nystagmus was replaced by periodic alternating gaze. Several days later, full eye movements returned, as did the periodic alternating nystagmus which had an identical periodicity to the periodic alternating gaze. The underlying pathophysiology of periodic alternating nystagmus and periodic alternating gaze is discussed.

Adult↗
PubMed1998

Medicare program; schedule of limits on home health agency costs per visit for cost reporting periods beginning on or after October 1, 1997--HCFA. Notice with comment period.

This notice sets forth a revised schedule of limits on home health agency costs that may be paid under the Medicare program for cost reporting periods beginning on or after October 1, 1997. These limits replace the per visit limits that were set forth in our July 1, 1996 notice with comment period (61 FR 34344) and supersede those set forth in our July 1, 1997 notice with comment period (61 FR 35608). This notice also provides, in accordance with the Balanced Budget Act of 1997, that there be no changes in the home health per visit limits for cost reporting periods beginning on or after July 1, 1997 and before October 1, 1997 (that is, the cost limits set forth in our July 1, 1996 notice will apply to cost reporting periods beginning during this time period); that the establishment of the cost per visit limitations for cost reporting periods beginning on or after October 1, 1997 be based on 105 percent of the median of the labor-related and nonlabor per visit costs for freestanding home health agencies; that there be no updates in the home health costs limits (including no adjustments for changes in the wage index or other updates) for cost reporting periods beginning on or after July 1, 1994 and before July 1, 1996; and the wage index value that is applied to the labor portion of the per visit limitations be based on the geographic area in which the home health service is furnished.

Centers for Medicare and Medicaid Services, U.S.↗
PubMed2001

The Drosophila double-timeS mutation delays the nuclear accumulation of period protein and affects the feedback regulation of period mRNA.

The Drosophila double-time (dbt) gene, which encodes a protein similar to vertebrate epsilon and delta isoforms of casein kinase I, is essential for circadian rhythmicity because it regulates the phosphorylation and stability of period (per) protein. Here, the circadian phenotype of a short-period dbt mutant allele (dbt(S)) was examined. The circadian period of the dbt(S) locomotor activity rhythm varied little when tested at constant temperatures ranging from 20 to 29 degrees C. However, per(L);dbt(S) flies exhibited a lack of temperature compensation like that of the long-period mutant (per(L)) flies. Light-pulse phase-response curves were obtained for wild-type, the short-period (per(S)), and dbt(S) genotypes. For the per(S) and dbt(S) genotypes, phase changes were larger than those for wild-type flies, the transition period from delays to advances was shorter, and the light-insensitive period was shorter. Immunohistochemical analysis of per protein levels demonstrated that per protein accumulates in photoreceptor nuclei later in dbt(S) than in wild-type and per(S) flies, and that it declines to lower levels in nuclei of dbt(S) flies than in nuclei of wild-type flies. Immunoblot analysis of per protein levels demonstrated that total per protein accumulation in dbt(S) heads is neither delayed nor reduced, whereas RNase protection analysis demonstrated that per mRNA accumulates later and declines sooner in dbt(S) heads than in wild-type heads. These results suggest that dbt can regulate the feedback of per protein on its mRNA by delaying the time at which it is translocated to nuclei and altering the level of nuclear PER during the declining phase of the cycle.

Alleles↗
PubMed2002

Mutations linked to familial hypokalaemic periodic paralysis in the calcium channel alpha1 subunit gene (Cav1.1) are not associated with thyrotoxic hypokalaemic periodic paralysis.

OBJECTIVE: To investigate whether patients with thyrotoxic hypokalaemic periodic paralysis (THPP) have the same molecular defect in the calcium channel gene described in familial hypokalaemic periodic paralysis (FHPP), as the symptoms of both diseases are comparable, we analysed, in patients with THPP, the presence of mutations R528H, R1239H and R1239G on the S4 voltage-sensing transmembrane segment of the alpha1 subunit of the calcium channel gene (Cav1.1). DESIGN AND PATIENTS: Genomic DNA was extracted from peripheral blood from 14 patients with THPP, 13 sporadic cases and one with a family history. An FHPP family was selected as a positive control. The exons bearing the described mutations were amplified by PCR, screened by single-strand conformation polymorphism (SSCP), and further sequenced. MEASUREMENTS: THPP was diagnosed both clinically and through laboratory tests, all patients having elevated levels of thyroid hormones (T4, T3 or free T4), suppressed TSH and plasma potassium below 3 small middle dot5 mmol/l. RESULTS: No evidence of the described mutations was found in patients with THPP. Furthermore, we did not detect any mutations in any of the four full S4 voltage-sensing transmembrane segments of Cav1 small middle dot1 (DIS4, DIIS4, DIIIS4 and DIVS4) by direct sequencing. However, close to the R528H mutation, we identified two single nucleotide polymorphisms at nucleotides 1551 and 1564 in both familial and sporadic cases with THPP. In addition, we were able to detect the R528H mutation in the DIIS4 transmembrane segment in all members of the FHPP family. CONCLUSION: Mutations linked to familial hypokalaemic periodic paralysis in the calcium channel alpha1 subunit gene (Cav1.1) are not associated with thyrotoxic hypokalaemic periodic paralysis. However, polymorphisms in nucleotides 1551 and 1564 in the exon 11 were found in patients with familial hypokalaemic periodic paralysis and thyrotoxic hypokalaemic periodic paralysis in higher frequency than in controls. The polymorphisms identified within the Cav1.1 gene are associated with thyrotoxic hypokalaemic periodic paralysis and represent a novel finding.

Adult↗
PubMed2005

Cardiac fibrinolytic capacity is markedly increased after brief periods of local myocardial ischemia, but declines following successive periods in anesthetized pigs.

BACKGROUND: Fibrinolysis in blood is mainly reflected by the activities of tissue plasminogen activator (tPA) and of plasminogen activator inhibitor-1 (PAI-1). The effect of myocardial ischemia on their activities in the coronary circulation is, however, not established. OBJECTIVES: With an improved experimental model, we therefore examined the effect of a brief period of myocardial ischemia on their activities. Furthermore, the consequences of repeated periods of ischemia, mimicking the situations in patients with unstable angina, were investigated. METHODS: In six anesthetized pigs, we occluded the distal left anterior descending coronary artery (LAD) four times for 10 min with 40 min intervals and determined the activities of tPA and PAI-1 in arterial and coronary venous blood. By simultaneously recording LAD flow, we could estimate cardiac release of these factors at baseline conditions and during reperfusion. RESULTS: Neither net cardiac release of PAI-1 nor alterations in plasma PAI-1 levels were demonstrated during the experiment. However, a significant net release of tPA activity of 10.4 +/- 3.2 IU mL(-1) (P < 0.005) was recorded during baseline conditions. During reperfusion following the first period of ischemia, the cardiac release of tPA activity increased to a peak of 103 +/- 30-fold baseline release, but declined progressively after repeated periods of ischemia. After the fourth period, tPA release did not exceed an estimated baseline accumulation during ischemia and early reperfusion. CONCLUSIONS: In this porcine model, a substantial local increase in fibrinolytic capacity was observed after brief periods of ischemia, but declined subsequently by repeated periods of ischemia.

Angina Pectoris↗
PubMed1996

Thyrotoxic periodic paralysis, an unusual cause of hypokalemic periodic paralysis.

Over a two-year period two patients were admitted to the hospital with episodes of paralysis and hypokalemia. In the first patient, familial hypokalemic periodic paralysis was initially suspected. Only several months later was Graves' disease diagnosed and this diagnosis linked to thyrotoxic periodic paralysis. The second patient came to notice after treatment with thyreostatic drugs was stopped prematurely and paralysis together with hypokalemia developed. Thyrotoxic periodic paralysis, being rare outside Asia, closely mimics the clinical presentation of familial hypokalemic periodic paralysis. Mainly men in the third decade with a negative family history are affected. Graves' disease is the most common cause of hyperthyroidism. This disorder is not always clinically apparent since signs of hyperthyroidism may be easily missed. Therefore thyroid function tests are part of the diagnostic workup of hypokalemic periodic paralysis. Correction of thyroid function is essential to treatment. The pathophysiology is still controversial.

Antithyroid Agents↗
PubMed2004

A severe autosomal-dominant periodic inflammatory disorder with renal AA amyloidosis and colchicine resistance associated to the MEFV H478Y variant in a Spanish kindred: an unusual familial Mediterranean fever phenotype or another MEFV-associated periodic inflammatory disorder?

Familial Mediterranean fever (FMF) is an autosomal recessive disease characterized by recurring short attacks of fever and serositis. Secondary AA amyloidosis is the worst complication of the disease and often determines the prognosis. The MEFV gene, on chromosome 16p13.3, is responsible for the disease and around 30 mutations have been reported to date. Colchicine is the standard FMF treatment today, and prevents both attacks and amyloid deposition in 95% of patients. Here we describe a three-generation Spanish kindred with five family members affected by a severe periodic inflammatory disorder associated with renal AA amyloidosis and colchicine unresponsiveness. Clinical diagnosis of definite FMF disease was made based on the Tel-Hashomer criteria set. Genetic analyses revealed that all subjects were heterozygous for the new H478Y MEFV variant, segregating with the disease. In addition, mutations in the TNFRSF1A and CIAS1/PYPAF1/NALP3 genes, related to the dominantly inherited autoinflammatory periodic syndromes, were ruled out. However, the dominant inheritance of the disease, the long fever episodes with a predominant joint involvement, and the resistance to colchicine in these patients raise the question of whether the periodic syndrome seen in this kindred is a true FMF disease with unusual manifestations or rather another MEFV-associated periodic syndrome. We conclude that the new H478Y MEFV mutation is the dominant pathological variant causing the inflammatory periodic syndrome in this kindred and that full-length analyses of the MEFV gene are needed to obtain an adequate diagnosis of patients with clinical suspicion of a hereditary periodic fever syndrome, especially those from non-ancestral populations.

Adult↗
PubMed1979

Induction of suppressor cells by sodium periodate: the opposite expression of periodate-induced lymphocyte activation in spleen cells of normal and nude mice.

Normal mouse spleen cells treated with sodium periodate for 10 min at 4 degrees are stimulated to undergo blastogenesis and to incorporate thymidine. In contrast, periodate treatment does not stimulate DNA synthesis in nude mice spleen cells. The effect of such treatment on the antibody response in vitro induced by sheep red blood cells (SRBC) and by trinitrophenyl polyacrylamide (TNP-PAA), a T-independent antigen has been evaluated. Periodic-induced proliferation is accompanied by a marked inhibition of the immune response to both of these antigens in normal mouse spleen cells. Mild oxidation of nude cells with periodate markedly enhances their anti-TNP response elicited by TNP-PAA. The data suggest that periodate-induced immune suppression is associated with T lymphocytes. Furthermore, periodate-treated cells are capable of suppressing the in vitro antibody response of untreated normal cells.

Animals↗
PubMed1984

Dependence of lethality induced by a direct DNA perturbation of synchronized human diploid fibroblasts on different periods of the DNA synthetic period (S phase).

The cytotoxic effect of a direct perturbation of DNA during various portions of the DNA synthetic period (S phase) of cultured human diploid fibroblasts was examined. The cells were synchronized by a period of growth in low serum with a subsequent blockage of the cells at the G1/S boundary by hydroxyurea. This method resulted in over 90% synchrony, although approximately 20% of the cells were noncycling. Synchronized cells were treated for each of four 2-hour periods during the S phase with 5-bromodeoxyuridine (0.1-10 microM), followed by irradiation with near-UV (5-10 min). The 5-bromodeoxyuridine-plus-irradiation treatment was cytotoxic, while treatment with 5-bromodeoxyuridine alone or irradiation alone was not cytotoxic. The cytotoxicity was dependent upon the periods of S phase during which treatment was administered. The highest lethality was observed for treatment in early to middle S phase, particularly in the first 2 hours of S phase, whereas scarce lethality was observed in late S phase. The extent of substitution of 5-bromodeoxyuridine for thymidine in newly synthesized DNA was similar in every period of the S phase. Furthermore, no specific period during S phase was significantly more sensitive to treatment with respect to DNA damage, as determined by an induction of unscheduled DNA synthesis. These results suggest that a certain region or regions in the DNA of human diploid fibroblasts, as designated by their specific temporal relationship in the S phase, may be more sensitive to the DNA perturbation by 5-bromodeoxyuridine treatment plus near-UV irradiation for cell survival.

Bromodeoxyuridine↗
PubMed1992

The correlation between heart period variability and mean period length.

Heart rate variability and heart period variability are important indicators of the functioning of the autonomic nervous system and are strong predictors of survival after myocardial infarction. The standard deviation of a patient's series of normal heart periods (consecutive normal RR intervals) is positively and, in some populations, strongly correlated with the mean period length. This phenomenon has led some investigators to use the coefficient of variation as their measure of variability, because it correlates less strongly with the mean period length. Using data from a multicentre post-infarction natural history study, we show that the standard deviation of the instantaneous heart rates has, like the coefficient of variation, only a modest correlation with the mean period length. Unlike the coefficient of variation, however, this standard deviation is derivable from established statistical principles. We show further that the coefficient of variation, the standard deviation of heart rates, and the standard deviation of heart periods are approximately equally strong predictors of survival after myocardial infarction.

Aged↗
PubMed2002

Parathyroid hormone concentrations during and after two periods of high intensity exercise with and without an intervening recovery period.

The purpose of this study was to examine the effect of a recovery period between two periods of exercise on bone metabolism and related hormones. Concentrations of serum parathyroid hormone ([PTH]), plasma ionized calcium ([Ca(2+)]) and total calcium were measured. A group of 12 healthy men aged 20-27 years participated in this study. They took part in two exercise protocols (P(1) and P(2)) on two separate weeks. The exercise in P(1) comprised two successive periods of 21 min each at 70% and 85% of maximal oxygen uptake; P(2) comprised two periods of exercise at the same intensities but separated by 40 min of recovery. Venous blood samples were collected 1 day before the sessions (control), before each protocol, during (7th and 21st min), at the end (42nd min in P(1) and 82nd min in P(2)) and after 24 h of recovery. The [PTH] was significantly elevated during the two protocols ( P<0.01), remained raised in P(1) after 24 h of recovery ( P<0.05) and was significantly lower ( P<0.01) at the end of P(2) when compared to P(1). The [Ca(2+)] decreased significantly during and at the end of the two protocols ( P<0.01) and had returned to control values after 24 h of recovery. Plasma lactate concentration increased during the two protocols ( P<0.01) and returned to control values after recovery. These results indicate firstly that [Ca(2+)] decreases during continuous exercise as [PTH] increases and remains raised after 24 h of recovery, secondly that a recovery period between two periods of exercise attenuates the variations in [Ca(2+)] and [PTH], and thirdly that recovery may have anabolic effects on bone. However, the small physiological changes observed prevent us from forming any firm conclusion about this.

Adult↗
PubMed1999

Existence and global attractivity of positive periodic solutions of periodic n-species Lotka-Volterra competition systems with several deviating arguments.

In this paper, we study the existence and global attractivity of positive periodic solutions of periodic n-species Lotka-Volterra competition systems. By using the method of coincidence degree and Lyapunov functional, a set of easily verifiable sufficient conditions are derived for the existence of at least one strictly positive (componentwise) periodic solution of periodic n-species Lotka-Volterra competition systems with several deviating arguments and the existence of a unique globally asymptotically stable periodic solution with strictly positive components of periodic n-species Lotka-Volterra competition system with several delays. Some new results are obtained. As an application, we also examine some special cases of the system we considered, which have been studied extensively in the literature. Some known results are improved and generalized.

Animals↗
PubMed1999

Periodicity-dependent stiffness of periodic hydrophilic-hydrophobic heteropolymers.

From extensive Monte Carlo simulations of a Larson model of perfectly periodic heteropolymers (PHP) in water, a striking stiffening is observed as the period of the alternating hydrophobic and hydrophilic blocks is shortened. At short period and low temperature needlelike conformations are the stable conformations. As temperature is increased thermal fluctuations induce kinks and bends. At large periods compact oligomeric globules are observed. From the generalized Larson prescription, originally developed for modeling surfactant molecules in aqueous solutions, we find that the shorter the period is the more stretched the PHP is. This novel effect is expected to stimulate polymer synthesis and trigger research on the rheology of aqueous periodic heteropolymer solutions.

Journal Article↗