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PubMed2001

Solar UVR exposures of indoor workers in a Working and a Holiday Period assessed by personal dosimeters and sun exposure diaries.

BACKGROUND/AIM: The aim of this study was to quantify ultraviolet radiation (UVR) exposure of fully employed indoor workers during a Working Period and a Holiday Period in the summer months. A further aim was to investigate the correlation between individual personal UVR dosimeter reading and self-reported data in a diary about sun exposure habits and to investigate whether skin type, age and gender influence sun exposure. METHODS: The solar UVR, in standard erythema doses (SED) measured by UV sensitive spore-film filter type personal dosimeters (VioSpor), and sun exposure diaries were compared. The study included 44 healthy Danish adult indoor workers during a Working Period of a mean of 13 days and a Holiday Period of a mean of 17 days from June to September. RESULTS: The individual total UVR exposure correlated significantly (P<0.001) in both the Holiday and Working Periods with individual total hours spent outdoors from 07:00 to 19:00 and with skin area exposure hours. There was no significant correlation between sun exposure dose and gender, age or skin type I-IV, or between the individual solar exposure dose in the Working and the Holiday Period. However, subjects with UVR exposures in the upper quartile spent their Holiday Period in Southern Europe, and/or had been more than the mean time outdoors at the beach/sea and/or between 12:00 and 15:00. Subjects with UVR exposure in the lower quartiles spent their holidays in Denmark or Northern Europe and did not stay at the beach at all. They received an average solar UVR dose which was 22% of ambient in Denmark in the same period while subjects having their holidays in Southern Europe received as much as 90% of the ambient dose in Denmark. CONCLUSIONS: Despite information campaigns to avoid the midday sun, on average 35% of the recorded hours outdoors were spent between 12:00 and 15:00 in the Holiday Period. Total hours outdoors give the best estimate of the total sun exposure dose. Registration in a diary of total hours outdoors and whether the Holiday Period was in Northern or Southern Europe can be used to predict the solar exposure dose in a Holiday Period of a few weeks.

Adult↗
PubMed1996

Changes in the period of no respiratory sensation and total breath-holding time in successive breath-holding trials.

1. Immediately after breath-holding at end-expiratory level, there is a certain period of no particular respiratory sensation which is terminated by the onset of an unpleasant sensation and followed by progressive discomfort during breath-holding. This period, defined as the time from the start of voluntary breath-holding to the point where the onset of an unpleasant sensation occurs, is designated "the period of no respiratory sensation'. Although it has been shown that the maximum breath-holding performance is improved with successive trials, it is not clear whether this training effect exerts a similar influence on the period of no respiratory sensation during breath-holding. 2. Since the training effect seems to be associated with the stresses of breath-holding, we hypothesized that the initial period of no respiratory sensation during breath-holding might be less influenced by the training effect. 3. We studied 13 normal subjects who performed repeated breath holds while continuously rating their respiratory discomfort using a visual analogue scale. In addition, we measured the hypercapnic ventilatory response of each individual and obtained the relationship between the slope of the hypercapnic response curve and breath-holding periods. 4. Our results showed that there was little training effect on the period of no respiratory sensation and that the period of no sensation during breath-holding is inversely related to the slope of the hypercapnic ventilatory response curve. 5. The period of no respiratory sensation was also measured in eight patients with chronic obstructive pulmonary disease. The values of the period of no respiratory sensation in patients with chronic obstructive pulmonary disease were apparently lower than those obtained in normal subjects. 6. These findings suggest that measurement of the period of no respiratory sensation can be a useful clinical test for the study of genesis of dyspnoea.

Adult↗
PubMed1999

Epidemiology and prognosis of plantar melanoma in 62 Japanese patients over a 28-year period.

BACKGROUND: The plantar surface is one of the commonest sites of malignant melanoma in the Japanese; however, the biological behavior is not sufficiently clarified, because of the paucity of long-term studies. We attempted an epidemiologic survey of the cases of plantar melanoma treated in our institute to study the survival rate in the recent period. METHODS: Of the 207 cases of malignant melanoma observed over the past 28 years, 62 patients were diagnosed as having plantar melanoma. The proportion of plantar melanoma to all melanomas, the sex and age of the patients, and the histologic type, stage, and prognosis were evaluated by comparing those registered in the first half (1969-1982) and the second half (1983-1996) of the period. RESULTS: The proportions of plantar melanoma in the first and second half periods were 31% (28 out of 90) and 29% (34 out of 117), respectively. No sex difference in the patients was observed. The mean age of the patients was 67 years. Fifty-one lesions were histologically proven to be acral lentiginous melanoma (ALM), two were superficial spreading melanoma (SSM), and nine were nodular melanoma (NM). Of the nine NMs, eight were registered in the second half period. The heel was affected in 33 (53%), the metatarsal regions in nine (14%), the toes in six (10%), and the arch areas in 14 (23%). The proportion of the weight-bearing areas, including the heel, metatarsal areas, and toes, decreased in the second half period. A comparison of the stages of plantar melanoma showed that, in the first half period, there were 18% of patients with stage IV disease in contrast to none in the second half period. Conversely, the proportion of stage I and II disease was 50% in the second half period, whereas it was only 39% in the first half period. The 5-year survival rates in the first and second half periods were 56% and 71%, respectively. CONCLUSIONS: The prognosis of plantar melanoma has improved recently at our institute. The possible explanation for a trend to better survival in the second half period may be related to a decrease in stage IV disease as well as to an increase in the frequency of diagnosis of early stage disease.

Aged↗
PubMed1984

The hydrophobic moment detects periodicity in protein hydrophobicity.

Periodicities in the polar/apolar character of the amino acid sequence of a protein can be examined by assigning to each residue a numerical hydrophobicity and searching for periodicity in the resulting one-dimensional function. The strength of each periodic component is the quantity that has been termed the hydrophobic moment. When proteins of known three-dimensional structure are examined, it is found that sequences that form alpha helices tend to have, on average, a strong periodicity in the hydrophobicity of 3.6 residues, the period of the alpha helix. Similarly, many sequences that form strands of beta sheets tend to have a periodicity in their hydrophobicity of about 2.3 residues, the period typical of beta structure. Also, the few sequences known to form 3(10) helices display a periodicity of about 2.5 residues, not far from the period of 3 for an ideal 3(10) helix. This means that many protein sequences tend to form the periodic structure that maximizes their amphiphilicity. This observation suggests that the periodicity of the hydrophobicity of the protein primary structure is a factor in the formation of secondary structures. Moreover, the observation that many protein sequences tend to form segments of maximum amphiphilicity suggests that segments of secondary structure fold at a hydrophobic surface, probably formed from other parts of the folding protein.

Amino Acid Sequence↗
PubMed1990

Flumethason-induced calving is preceded by a period of myometrial inhibition during luteolysis.

The temporal relationship among changes of the concentrations of the 13,14-dihydro-15-keto metabolite of prostaglandin F2 alpha (PGFM), estrone (E1) and estrone sulphate (E1S) in maternal arterial plasma (MP) and amniotic fluid (AF), the prepartum progesterone (P4) decline in MP, and the evolution of uterine electromyographic (EMG) activity was investigated in 6 cows. Calving was induced by a single i.m. injection of 5 mg flumethason on Day 270 of gestation. The period under investigation was subdivided into four consecutive periods: Period 1 covered the last 2 days before flumethason treatment; Period 2 (mean +/- SEM duration: 16.1 +/- 2.5 h), Period 3 (8.8 +/- 1.1 h), and Period 4 (13.0 +/- 1.5 h) together included the interval between injection and the onset of the expulsive stage of induced parturition. Each was defined by its pattern of uterine EMG activity. During Periods 1 and 2, this activity occurred in long episodes (2-20 min; contractures) at a similar mean (+/- SEM) frequency (0.51 +/- 0.14/h and 0.42 +/- 0.07/h, respectively). No significant differences in hormonal concentrations in MP and AF between these two periods were detected. During Period 3, contractures nearly disappeared (freq: 0.09 +/- 0.05/h), and in MP mean P4 levels were significantly lower and PGFM levels were significantly higher than before. Mean PGFM concentrations in AF were not significantly changed during Period 3. Finally, during Period 4, EMG activity reappeared and a parturient EMG pattern gradually evolved in the presence of a further significant decline of P4 levels and significant increase of PGFM concentrations in MP.(ABSTRACT TRUNCATED AT 250 WORDS)

Amniotic Fluid↗
PubMed1989

Host genetic control of incubation periods of Creutzfeldt-Jakob disease in mice.

Host genetic control of the incubation period of Creutzfeldt-Jakob disease (CJD) was studied using various inbred strains of mice, including B10 congenic strains. Various incubation periods were found in mice injected either intracerebrally or intraperitoneally with the Fukuoka 1 strain of the CJD agent; NZW/Sea and A/JJms had the shortest, and B10.AKM/Ola and C57BL/6J the longest, incubation periods. Length of the CJD incubation period did not correlate with the genetic markers tested, i.e. the murine major histocompatibility (H-2) complex (which has previously been reported to be linked to a gene influencing CJD incubation period in mice), coat colour or sex genes. In NZW/Sea x C57BL/6J F1 hybrid mice the CJD incubation periods were similar to that of the parent with the longest incubation period. Incubation periods of the backcross progeny from F1 and NZW/Sea were intermediate between those of the parental mice and had a unimodal distribution pattern. A similar observation was made on the progeny of the A/JJms x C57BL/6J mating. On the other hand, the length of incubation period for the NZW/Sea x B10.AKM/Ola F1 hybrid fell between those for the two parents and the NZW/Sea x A/JJms F1 hybrid had a significantly longer incubation period than those of the two parents. These results suggest that polygenes probably control the length of the CJD incubation period in mice.

Alleles↗
PubMed2002

Mode locking of spatiotemporally periodic orbits in coupled sine circle map lattices.

We study the organization of mode-locked intervals corresponding to the stable spatiotemporally periodic solutions in a lattice of diffusively coupled sine circle maps with periodic boundary conditions. Spatially periodic initial conditions settle down to spatiotemporally periodic solutions over large regions of the parameter space. In the case of synchronized solutions resulting from synchronized initial conditions, the mode-locked intervals have been seen to follow strict Farey ordering in the temporal periods. However, the nature of the organization of the mode-locked intervals corresponding to higher spatiotemporal periods is highly dependent on initial conditions and on system parameters. Farey ordering in the temporal periods is seen at low coupling for mode-locked intervals of all spatial periods. On the other hand, stable spatial period two solutions show an interesting reversal of Farey ordering at high values of coupling. Other spatially periodic solutions show a complete departure from Farey ordering at high coupling. We also examine the issue of completeness of the mode-locked intervals via a calculation of the fractal dimension of the complement of the mode-locked intervals as a function of the coupling epsilon and the nonlinearity parameter K. Our results are consistent with completeness over a range of values for these parameters. Spatiotemporally periodic solutions of the traveling wave type have their own organization in the parameter space. Novel bifurcations to other types of solutions are seen in the mode-locked intervals. We discuss various features of these bifurcations. We also define a set of new variables using which an analytic treatment of the bifurcations along the Omega=0 line is carried out.

Journal Article↗
PubMed1984

The influence of stimulus type and stimulus strength on the silent period in human masticatory muscles.

The silent period in the jaw-closing muscles of nine healthy subjects was investigated. The stimulus types used were the open-close-clench movement (OCC), the mechanical chin tap and electrical skin stimulation. Irrespective of the jaw-closing speed for the OCC movements only the unmeasurable and single type silent periods were observed. Increasing the chin tap strength resulted in a decreasing percentage of single type silent periods and an increasing number of depressed, double and merged silent periods. The duration of the short and combined silent period was shorter for the OCC movements than for the chin taps. For the chin taps an increasing stimulus strength resulted in longer silent periods. Only the transition from hard to painful chin tap showed a slight, but significant decrease in short silent period duration. The beginning of the late inhibitory period, which could sometimes be evoked by electrical skin stimulation, coincided with the beginning of the second inhibitory phase of the chin-tap evoked double silent period. The long silent period as shown by one of the subjects cast doubt on the validity of the relationship between silent period duration and TMJ dysfunction.

Adult↗
PubMed2001

Bacteriophage latent-period evolution as a response to resource availability.

Bacteriophages (phages) modify microbial communities by lysing hosts, transferring genetic material, and effecting lysogenic conversion. To understand how natural communities are affected it is important to develop predictive models. Here we consider how variation between models--in eclipse period, latent period, adsorption constant, burst size, the handling of differences in host quantity and host quality, and in modeling strategy--can affect predictions. First we compare two published models of phage growth, which differ primarily in terms of how they model the kinetics of phage adsorption; one is a computer simulation and the other is an explicit calculation. At higher host quantities (approximately 10(8) cells/ml), both models closely predict experimentally determined phage population growth rates. At lower host quantities (10(7) cells/ml), the computer simulation continues to closely predict phage growth rates, but the explicit model does not. Next we concentrate on predictions of latent-period optima. A latent-period optimum is the latent period that maximizes the population growth of a specific phage growing in the presence of a specific quantity and quality of host cells. Both models predict similar latent-period optima at higher host densities (e.g., 17 min at 10(8) cells/ml). At lower host densities, however, the computer simulation predicts latent-period optima that are much shorter than those suggested by explicit calculations (e.g., 90 versus 1,250 min at 10(5) cells/ml). Finally, we consider the impact of host quality on phage latent-period evolution. By taking care to differentiate latent-period phenotypic plasticity from latent-period evolution, we argue that the impact of host quality on phage latent-period evolution may be relatively small.

Biological Evolution↗
PubMed1998

Periodic limb movement disorder and restless legs syndrome in children with attention-deficit hyperactivity disorder.

Sleep disruption can lead to symptoms of attention-deficit hyperactivity disorder (ADHD) in children. Since periodic limb movement disorder and/or restless legs syndrome can cause sleep disruption, we assessed whether these two specific sleep disorders are likely to occur in children with ADHD. We asked a series of 69 consecutive parents of children with ADHD questions about the symptoms of periodic limb movement disorder. Based on a positive response to these periodic limb movement disorder queries, 27 children underwent all-night polysomnography. Eighteen children (aged 2 to 15 years) of the 27 (26% of the 69 children with ADHD) had 5 or more periodic leg movements in sleep per hour of sleep and had complaints of sleep disruption, thus fulfilling the criteria for periodic limb movement disorder. A comparably age- and sex-matched group of children referred to a sleep laboratory for sleep complaints but without ADHD showed only a 5% prevalence (2 of 38 subjects) of periodic leg movements in sleep (P=.017). Eight of the 18 children with ADHD and periodic limb movement disorder and one of the two control patients with periodic limb movement disorder had both a personal and parental history of restless legs syndrome symptomatology. This study further documents the occurrence of periodic limb movement disorder and restless legs syndrome in children and is the first large-scale study establishing a possible comorbidity between ADHD and periodic limb movement disorder. We propose that the sleep disruption associated with periodic limb movement disorder and restless legs syndrome and the motor restlessness of restless legs syndrome while awake could contribute to the inattention and hyperactivity seen in a subgroup of ADHD-diagnosed children.

Adolescent↗
PubMed2005

Metabolic adaptations to repeated periods of contraction with reduced blood flow in canine skeletal muscle.

BACKGROUND: Patients suffering from Intermittent Claudication (IC) experience repeated periods of muscle contraction with low blood flow, throughout the day and this may contribute to the hypothesised skeletal muscle abnormalities. However, no study has evaluated the consequences of intermittent contraction with low blood flow on skeletal muscle tissue. Our aim was to generate this basic physiological data, determining the 'normal' response of healthy skeletal muscle tissue. We specifically proposed that the metabolic responses to contraction would be modified under such circumstances, revealing endogenous strategies engaged to protect the muscle adenine nucleotide pool. Utilizing a canine gracilis model (n = 9), the muscle was stimulated to contract (5 Hz) for three 10 min periods (separated by 10 min rest) under low blood flow conditions (80% reduced), followed by 1 hr recovery and then a fourth period of 10 min stimulation. Muscle biopsies were obtained prior to and following the first and fourth contraction periods. Direct arterio-venous sampling allowed for the calculation of muscle metabolite efflux and oxygen consumption. RESULTS: During the first period of contraction, [ATP] was reduced by approximately 30%. During this period there was also a 10 fold increase in muscle lactate concentration and a substantial increase in muscle lactate and ammonia efflux. Subsequently, lactate efflux was similar during the first three periods, while ammonia efflux was reduced by the third period. Following 1 hr recovery, muscle lactate and phosphocreatine concentrations had returned to resting values, while muscle [ATP] remained 20% lower. During the fourth contraction period no ammonia efflux or change in muscle ATP content occurred. Despite such contrasting metabolic responses, muscle tension and oxygen consumption were identical during all contraction periods from 3 to 10 min. CONCLUSION: repeated periods of muscle contraction, with low blood flow, results in cessation of muscle ammonia production which is suggestive of a dramatic reduction in flux through AMP deaminase.

Adaptation, Physiological↗
PubMed2006

Recent improvement in lung cancer screening: a comparison of the results carried out in two different time periods.

To evaluate recent improvements in lung cancer screening, we compared the results of recently conducted lung cancer screening with those of a previous screening. This study compared the survival of lung cancer patients detected by lung cancer screening conducted between 1976 and 1984 (early period) with that conducted between 1989 and 1997 (late period). Two hundred seventy-six patients with lung cancer were detected in the early period and 541 patients with lung cancer were detected in the late period. The median survival time (late : 49.8 vs. early : 27.8 months) and the 5-year survival rate (late : 47.8 vs. early : 34.8%) of the patients with lung cancer detected in the late period were significantly better than those in the early period (p = 0.0054). Among patients undergoing resection, the proportion of pathological stage I patients in the late period was significantly higher than that in the early period (late : 60.8 vs. early : 54.9%, p = 0.005). Multivariate analysis showed that the screening time period was a significant prognostic factor (hazard ratio = 0.685, 95% confidence interval : 0.563-0.832, p = 0.0002). These results were consistent with the findings of case-control studies of lung cancer screening programs in the late period recently conducted in Japan, which also showed a greater efficacy for screening than for previous case-control studies in the early period.

Adult↗
PubMed2000

Total radioactive residues and clenbuterol residues in swine after dietary administration of [14C]clenbuterol for seven days and preslaughter withdrawal periods of zero, three, or seven days.

Nine barrows (23.8 +/- 0.9 kg) and 9 gilts (23.1 +/- 0.9 kg) were used to determine the disposition of radiocarbon after oral [14C]clenbuterol (4-amino-alpha-[t-butylaminomethyl]-3,5-dichlorobenzyl [7-(14)C]alcohol hydrochloride) administration and to determine total and parent residues in edible tissues. Three barrows and three gilts, housed in metabolism crates, were fed 1 ppm [14C]clenbuterol HCl for seven consecutive days in three separate trials; a single barrow and gilt from each trial was slaughtered after 0-, 3-, or 7-d preslaughter withdrawal periods. Urine and feces were collected during the dosing and the withdrawal period; edible and inedible tissues were collected at slaughter. Total recovery of radiocarbon was 94.2 +/- 6.5%. Total clenbuterol absorption was greater than 75% for barrows and 60% for gilts. Total radioactive residues in tissues were not different (P > 0.05) between barrows and gilts. Concentrations of parent clenbuterol in liver, kidney, skeletal muscle, adipose tissue, and lung did not differ between barrows and gilts (P > 0.05). Total radioactive and parent residues declined in tissues as withdrawal period increased. After the 0-d withdrawal period, total liver residues (286 ppb) were approximately equal to lung residues, twice those of the kidney, and about 15 times those of adipose tissue and skeletal muscle. After a 7-d withdrawal period, total radioactive residues in liver (15 ppb) were roughly three times greater than lung, kidney, and adipose tissue total residues and about 13 times those of skeletal muscle total residues. Parent clenbuterol represented 79, 63, 42, 67, and 100% of the total radioactive residue in adipose tissue, kidney, liver, lung, and skeletal muscle, respectively, in hogs slaughtered with a 0-d withdrawal period. With increasing withdrawal period, the percentage of total radioactive residue present as parent clenbuterol within edible tissues (including lung) decreased, so that after a 7-d withdrawal period, 7, 16, and 29% of the total residue was composed of parent clenbuterol in kidney, liver, and lung, respectively. After a 7-d withdrawal period, parent clenbuterol exceeded the European maximum residue limit (0.5 ppb) 4.6-fold in liver and 2.4-fold in lung. In muscle, clenbuterol was approximately 40 times the limit after a 0-d withdrawal period but had dropped below 0.5 ppb after a 3-d withdrawal period. Results from this study indicate that clenbuterol HCl is well absorbed in swine and that the use of clenbuterol in this species in an off-label manner is inconsistent with human food safety standards used in developed countries.

Animals↗
PubMed2006

Effects of level of feed intake on pancreatic exocrine secretions during the early postweaning period in piglets.

The objective of this study was to determine the influence of the level of feed intake and a 2-d feed restriction period on the postweaning adaptation of pancreatic exocrine secretions. At 33 d of age, 18 piglets fitted with 2 permanent catheters (for pancreatic juice collection and reintroduction) were weaned and allocated to 1 of the following 2 dietary treatments for 5 d: restricted feed allocation (restricted) or gradually increasing feed allocation (control). Pancreatic juice was collected daily during both basal and prandial periods. The basal period was defined as the period from 1400 to 1700 h (i.e., 5 to 8 h after the morning meal), whereas the prandial period was defined as the period from 30 min before to 60 min after the morning meal (given at 0900). Digestive enzyme activities and antibacterial activity were determined. Pancreatic protein secretion was 44% less (P < 0.05) in restricted piglets than in control piglets during the basal period. Trypsin secretion was affected by feed-restriction of piglets. The meal did not affect protein and trypsin secretions in restricted piglets, whereas at d 3 postweaning, protein and trypsin secretions and trypsin specific activity in control piglets were 9-, 105-, and 25-fold greater (P < 0.001) during the first 30 min after the meal than before the meal. Lipase and amylase secretions were not affected by variations in feed intake. The secretion of antibacterial activity in restricted piglets was greater (P < 0.05) than that of control piglets only at d 5. The extended feed restriction period increased the basal secretion of antibacterial activity (P = 0.09) and postprandial secretion of amylase (P = 0.05). In conclusion, a low level of feed intake during the early postweaning period decreased pancreatic protein and trypsin secretions, whereas a 2-d feed restriction period enhanced secretions of amylase and antibacterial activity. In addition, our results indicate that during periods of dietary adaptation, such as at weaning, measurements of enzyme activities in the tissue do not accurately reflect the enzyme secretion.

Animal Feed↗
PubMed2003

Invited review: bovine studies on optimal lengths of dry periods.

Milk production per cow has increased as a result of progressive changes in the genetics and management of the dairy animal population. A management constant during many decades of progress has been the widely adopted dry period length of 51 to 60 d. The scientific basis for that industry standard was examined to assess its validity as the appropriate standard for the modern dairy industry. If subsequent milk yields can be sustained fully after dry periods that are shorter than the current standard, then considerable milk is being forfeited by retaining longer dry periods. Conversely, failure to allow any dry period will result in a significant decrease in subsequent milk synthesis and secretion. Most studies to determine the minimum length of dry period required have involved retrospective analyses of observational data. Only five experiments have been reported in which dairy cows were assigned, at random, to planned 30- and 60-d dry periods. Estimates of the change in subsequent milk production when days dry were decreased from 50 to 57 d to 30 to 34 d ranged from a 10% decrease to a 1% increase. However, lower yields after shorter dry periods may be partially offset by greater milk yields in the previous lactation if such cows are milked 3 to 4 wk longer. Environmental factors that influence milk production as well as the biological processes that occur within the mammary gland during the nonlactating period must be considered when dry period lengths are compared. Importantly, additional animal trials that specifically assign cows randomly to the dry period lengths to be evaluated are needed to determine optimal dry period lengths for modern dairy cows in differing management scenarios.

Animals↗
PubMed1999

[Minimally invasive coronary bypass: optimal performance after a learning period].

Minimally invasive cardiac surgery requires a learning period before the advantages of the method can be demonstrated. We report the progress of our results over 21 consecutive months. 27 patients were considered for minimally invasive coronary bypass via a small thoracotomy. We compare the results of four consecutive groups corresponding to an initial period (July-December 1997; n = 7; 66.8 +/- 8.9 years), an intermediate period (January-June 1998; n = 4; 48.1 +/- 11.2 years), an advanced period (July-December 1998; n = 7; 62.9 +/- 7.0 years) and a current period (January-March 1999; n = 7; 59.3 +/- 10.9 years). 2 patients were converted to sternotomy during the first year of experience. The operating time was reduced from 124 +/- 14 min and 118 +/- 20 min during the initial and intermediate periods to 99 +/- 18 and 98 +/- 18 min during the last two periods. The ICU stay was 2.6 +/- 1.1 days during the initial period and diminished respectively to 1.5 +/- 0.6, 1.7 +/- 0.8 and 1.6 +/- 0.5 days during the intermediate, advanced and current periods. The postoperative hospital stay was reduced from 9.0 +/- 1.4 days to 6.3 +/- 4.6, 5.2 +/- 1.7 and 5.9 +/- 1.5 days respectively. The benefits of minimally invasive coronary bypass were estimated by comparing the results of the last two periods with those of patients operated on through a sternotomy, on a beating heart (n = 12; 62.6 +/- 8.2) or under CPB (n = 81; 63.0 +/- 8.5). In these situations, operative time was 144 +/- 41 min and 180 +/- 35 min respectively. The ICU stay was 1.5 +/- 0.6 and 2.2 +/- 0.9 days, and the postoperative hospital stay was 7.5 +/- 2.8 and 8.6 +/- 3.0 days. We conclude that a learning period is necessary before the real benefits of the minimally invasive approach to coronary disease can be demonstrated. This method will soon replace traditional sternotomy in certain indications.

Aged↗
PubMed2000

[Bone turnover in lactating adolescent: evaluation at the end of pregnancy, during and after the weaning period].

BACKGROUND: There is paucity of information about bone metabolism during pregnancy or breast feeding in teenagers. AIM: To study bone turnover at the end of pregnancy and during breast feeding in teenagers and correlate it with environmental, hormonal or nutritional variables. SUBJECTS AND METHODS: Thirty teenagers during their breast feeding period after a first pregnancy and 30 nulliparous girls matched for age, age of menarche and body mass index were assessed three weeks after delivery (period 1), at six months of breast feeding (period 2) and one year after the lactating period (period 3). Calcium intake and plasma calcium, phosphorus, alkaline phosphatases, parathormone, estradiol and prolactin were measured. Calcium, creatinine and hydroxyproline were also measured in a morning urine sample. RESULTS: Lactating and control girls were aged 16.3 +/- 0.8 and 16.1 +/- 0.7 years old respectively. Calcium intake in lactating and control girls was 798 +/- 421 and 640 +/- 346 g/day respectively in period 1, 612 +/- 352 and 592 +/- 309 mg/day in period 2 and 495 +/- 180 and 456 +/- 157 g/day in period 3. During periods 1 and 2, lactating girls had higher alkaline phosphatases (161 +/- 37 compared to 119 +/- 28 U/l and 149 +/- 37 compared to 106 +/- 23 U/l), parathormone (4.3 +/- 2.6 compared to 2.8 +/- 0.8 ng/dl and 3.6 +/- 1.6 compared to 3.0 +/- 0.9 ng/dl) and urinary hydroxyproline (95 +/- 16 compared to 63 +/- 15 mg/g creatinine and 84 +/- 19 compared to 59 +/- 15 mg/g creatinine). No differences were observed in period 3. No correlation between bone turnover variables, body mass index or hormonal parameters, was observed. CONCLUSIONS: In teenagers, there is an increase in bone turnover at the end of pregnancy, that persists during the lactating period. These changes are not related to nutritional or hormonal variables.

Adolescent↗
PubMed2005

Lack of adequate blood pressure control in the morning and evening periods in medicated hypertensive patients considered to be controlled in the office.

BACKGROUND AND AIM: In hypertensive patients tight blood pressure (BP) control during the critical morning and evening periods may be relevant for preventing cardiovascular events, which most frequently occur at these times of the day. METHODS: In a prospective study we evaluated 24h ambulatory BP (ABP) values (24h, daytime, nighttime, morning period between 6-10 am and evening period between 6-10 pm), in 103 hypertensive patients (HTs), aged between 18-79 years, considered to be controlled in the office in the previous two months (office BP < 140/90 mmHg, 2 x 3 readings, before taking medication), who were being treated with antihypertensive drugs taken once daily in the morning. Based on ABP data, HTs were considered to have good BP control if daytime BP values were < 135/85 mmHg, < 133.1/85.4 mmHg during the morning period, and < 138.1/89.3 mmHg during the evening period. Otherwise control of ABP was considered poor. These limits correspond to the upper 95% confidence limits of BP calculated for each period in a normotensive control population of 210 subjects age-matched to the HTs. RESULTS: Of the 103 HTs, 39 were under monotherapy and the remaining 64 on combination regimens (34 with two drugs, 29 with three and one with four). Based on ABP data of the 103 HTs, poor ABP control was observed in 36 (35%) in the morning period, in 24 (23%) in the evening period and in 29 (28%) for daytime BP values. ABP values during both the morning and evening periods correlated significantly with daytime values (r = 0.72 and r = 0.89 respectively, p < 0.01) but not with office values. CONCLUSIONS: A significant proportion of treated HTs who are considered to be controlled in the office present abnormally high ABP levels, particularly in the critical early morning period, but also during the evening and throughout the daytime period.

Adolescent↗