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PubMed2006

[Clinical application of the 24 hour IOP monitoring in the diagnose of the normal tension glaucoma suspects].

PURPOSE: To determine the value of 24-hour IOP monitoring in routine clinical practice of the suspects of normal tension glaucoma (NTG). METHODS: Fifty-one suspects of NTG (51 eyes) were selected for 24-hour IOP monitoring without any antiglaucoma therapy. RESULTS: In all of 51 eyes, there were only 18 (35.3%) eyes's IOP kept in the statistic normal range and the IOP variation amplitude were under 6 mm Hg, 33 eyes (64.7%) have large diurnal fluctuations in IOP or the peak IOP up to 21 mm Hg. The mean of the IOP variation amplitude ,mean and peak of the 24-hour monitoring was 4.65 mm Hg, 1.64 mm Hg and 3.96 mm Hg higher than of the daytime IOP measurement (P < 0.001). CONCLUSIONS: Compared with the daytime IOP measurement, the 24-hour IOP monitoring could identify diurnal IOP and/or IOP spikes better.

Adult↗
PubMed2004

Use of CA125 fluctuation during the menstrual cycle as a tool in the clinical diagnosis of endometriosis; a preliminary report.

OBJECTIVE: To elucidate whether endometriosis can be diagnosed clinically by assessing the differences between serum CA125 levels during menstruation and during the rest of the menstrual cycle. METHODS: The study was performed in 28 patients who underwent laparoscopy to check for pelvic causes of infertility. Patients with endometriosis were selected as the study group, and patients with normal laparoscopic findings functioned as the control group. Blood specimens were taken for CA125 determination during menstruation and during the rest of the menstrual cycle. Mean serum CA125 concentrations were compared by the two-sample t-test for between-group comparisons and the paired t-test for within-group comparisons. The receiver operating characteristic curve was applied to assess the usefulness of CA125 level changes during the menstrual cycle in the clinical diagnosis of endometriosis. RESULTS: The mean CA125 concentrations of healthy women during menstruation and during the rest of the menstrual cycle were 12.2 and 10 U ml(-1), respectively. In this group, the mean CA125 concentration was an average of 22% higher during menstruation than during the rest of the menstrual cycle (P < 0.001). The patients with endometriosis showed a similar pattern to that of normal women, but the levels differed by 198.3% in these patients (P < 0.001). Mean CA125 concentrations of these patients during menstruation and in the rest of the cycle were 35.8 and 12 U ml(-1), respectively. The mean CA125 concentration during menstruation was significantly higher in patients with endometriosis than in normal women (P < 0.001), but CA125 concentrations at other points in the menstrual cycle were found to be similar in both groups (P > 0.05). ROC curve analyses set a cutoff of 83% (percentage increment of CA125 level during menstruation compared with that on days without menstrual bleeding), which gives a sensitivity of 93% and specificity of 92%, with a corresponding likelihood ratio of 11.3. CONCLUSIONS: It may be possible to diagnose endometriosis clinically by assessment of the differences in CA125 level during menstruation as against the remainder of the menstrual cycle.

Adolescent↗
PubMed2003

Selected contribution: chronic intermittent hypoxia enhances respiratory long-term facilitation in geriatric female rats.

Age and the estrus cycle affect time-dependent respiratory responses to episodic hypoxia in female rats. Respiratory long-term facilitation (LTF) is enhanced in middle-aged vs. young female rats (72). We tested the hypothesis that phrenic and hypoglossal (XII) LTF are diminished in acyclic geriatric rats when fluctuating sex hormone levels no longer establish conditions that enhance LTF. Chronic intermittent hypoxia (CIH) enhances LTF (41); thus we further predicted that CIH would restore LTF in geriatric female rats. LTF was measured in young (3-4 mo) and geriatric (20-22 mo) female Sasco Sprague-Dawley rats and in a group of geriatric rats exposed to 1 wk of nocturnal CIH (11 vs. 21% O2 at 5-min intervals, 12 h/night). In anesthetized, paralyzed, vagotomized, and ventilated rats, time-dependent hypoxic phrenic and XII responses were assessed. The short-term hypoxic response was measured during the first of three 5-min episodes of isocapnic hypoxia (arterial Po2 35-45 Torr). LTF was assessed 15, 30, and 60 min postepisodic hypoxia. Phrenic and XII short-term hypoxic response was not different among groups, regardless of CIH treatment (P > 0.05). LTF in geriatric female rats was smaller than previously reported for middle-aged rats but comparable to that in young female rats. CIH augmented phrenic and XII LTF to levels similar to those of middle-aged female rats without CIH (P < 0.05). The magnitude of phrenic and XII LTF in all groups was inversely related to the ratio of progesterone to estradiol serum levels (P < 0.05). Thus CIH and sex hormones influence the magnitude of LTF in geriatric female rats.

Aging↗
PubMed2000

Developmental instability in japanese quail genetically selected for contrasting adrenocortical responsiveness.

Differences in developmental instability were assessed with Japanese quail of two lines that had been genetically selected over several generations for reduced (low stress, LS) or exaggerated (high stress, HS) plasma corticosterone response to brief mechanical restraint. At 32 wk of age, three bilateral traits were selected for study in each quail line. The characteristics chosen were length of the metatarsus (shank length, SHL), diameter of the shank (SHD) perpendicular to the spur, and distance between the auditory canal and the nares (face length, FL). Significantly greater bilateral trait size variances were associated with the measurement of SHL (P < 0.0088) and FL (P < 0.0016) in the HS line than in the LS line. SHD variances did not differ (P = 0.22) in quail of the HS and LS lines. These findings suggest that developmental instability (i.e., fluctuating asymmetry, FA) is more pronounced in HS quail than in LS quail. Previous studies have shown that not only do quail of the HS line show greater adrenocortical responsiveness to a wide range of stressors but that they are also more easily frightened than LS birds. Therefore, the line differences in FA found here may reflect the birds' differential responsiveness to chronic social and physical environmental stressors. The present findings also support previous suggestions that measuring asymmetries in bilateral traits could be an additional and valid method of assessing stress and of comparing phenotypic stability in selected populations.

Adrenal Cortex↗
PubMed1987

Immunoreconstitution of T-cell impairments in asymptomatic male homosexuals by thymic humoral factor (THF).

The feasibility of using Thymic Humoral Factor (THF) for immunomodulation in asymptomatic male homosexuals was evaluated in a study on fifteen subjects with T-cell impairments, selected on the basis of a 2SD reduction in T helper/inducer (T4+) cells and one additional lymphocytic defect. Following two biweekly courses of treatment, mean relative increments of T4+ (P less than 0.002), T3+ (P less than 0.02) and total lymphocyte (P less than 0.05) populations of the group receiving THF (n = 7) were significantly increased when compared to the placebo group (n = 8). In addition, a transient increase in T4+ lymphocytes was observed after the first course in the two individuals of the THF-treated group who were seropositive for HTLV-III/LAV but not in those who were seronegative. No difference was found between the groups in fluctuations of serum interferon (IFN) or proliferation of peripheral mononuclear cells to mitogens. The results of this limited trial demonstrate that THF is capable of correcting T-cell impairments that may predispose asymptomatic homosexuals to infection by HTLV-III, without affecting IFN production. These findings suggest that future strategies for AIDS prevention in high-risk groups should include institution of large controlled trials in immunodeficient, asymptomatic, HTLV-III/LAV-seronegative male homosexuals to study the potential of selective immunoreconstitution as a preventive measure against HTLV-III/LAV infection.

Acquired Immunodeficiency Syndrome↗
PubMed2000

Catechol-O-methyltransferase (COMT) inhibitors in Parkinson's disease.

Catechol-O-methyltransferase (COMT) inhibitors are a new therapeutic option in the treatment of patients with Parkinson's disease. COMT inhibitors act by extending the duration of action of levodopa, thus improving the amount of time a patient can experience benefit from levodopa. COMT inhibitors are only used in conjunction with levodopa. They do have a propensity to augment dopaminergic effects, such that levodopa doses might need to be adjusted downward. Other side effects of COMT inhibitors include diarrhea and liver function abnormalities. Due to the latter, recent guidelines have been developed to monitor patients on tolcapone for this rare side effect, and these guidelines will be discussed. This article also provides representative case histories for the appropriate use of COMT inhibitors that illustrate how these drugs can be used to manage patients with a fluctuating response to levodopa.

Antiparkinson Agents↗
PubMedDate not supplied

Heterozygosity and craniofacial dimensions of Zapotec school children from a subsistence community in the valley of Oaxaca, southern Mexico.

Gene flow is associated with differences in craniofacial and postcranial dimensions among indigenous populations of southern Mexico. This study compares four craniofacial dimensions in 322 children from families which have an average inbreeding coefficient of 0.01 and 36 children from families which have an inbreeding coefficient of zero (more heterozygous) in a Zapotec speaking community. In addition, two indices were computed. With sex and chronological age constant, there is a statistically significant difference between more and less heterozygous children in bizygomatic diameter. Differences in biparietal diameter and fronto-occipital length reflect the same tendency. The differences probably reflect more an effect of heterozygosity on these dimensions than facial dissimilarity of the populations from which the new genetic materials were drawn because gene flow was from related groups of Indians (e.g., Mixtec) in southern Mexico. Hence, midface growth and overall normal size appear to be affected by fluctuation in level of heterozygosity.

Analysis of Variance↗
PubMed2004

Prognostic significance of monthly weight fluctuations among older nursing home residents.

BACKGROUND: Although weight change in older persons has proven prognostic significance, it is not known whether monthly weights obtained by the clinical staff in long-term care institutions are reliable enough to be useful in identifying at-risk residents. The objective of this study was to determine whether an association exists between mortality risk and the intraresident variation in weight in long-term care institutions. METHODS: For this study, 900 nursing home residents with a recently identified nutritional problem from 96 long-term care facilities in 8 states were randomly selected. At study entry, nutritional, health status, and demographic data were extracted from the nursing home chart or the Minimum Data Set. Weights obtained by the nursing home staff were recorded at baseline and during each of the subsequent 6 months. Cox proportional hazards regression analysis was used to assess relationships between weight parameters and mortality risk during the 7 months of observation. RESULTS: During the study, 435 (48%) participants had at least 1 monthly weight that differed from the previous month's weight by > or =5%; 163 (18%) participants had this magnitude of a 1-month weight change more than once. By controlling for the linear trend (i.e., slope) of each residents' weight change between the first to the last weight, the average month-to-month residual variability in the resident's weights was calculated. This residual variability or "average random fluctuation" in weight from 1 month to the next was > or =2% in 229 (25%) participants and > or =3% in 82 (9%) participants. Despite the large random fluctuation in the residents' weights, weight loss was an important prognostic indicator. Those who lost > or =5% in any month had a 10-fold increased risk for death compared with those who gained weight (adjusted relative risk, 10.6; 95% confidence interval, 3.2 to 35.5). The average random fluctuation in weight was associated with an increased risk for death only at the upper 10th percentile for the population. CONCLUSIONS: Many nutritionally compromised elderly nursing home residents experience significant bidirectional fluctuations in their weight from month to month. How much of this variability is due to measurement error is not known. However, a weight loss of > or =5% in any month has important prognostic implications.

Aged↗
PubMed1997

Antennal asymmetry and sexual selection in a cerambycid beetle.

Cerambycid beetles have exaggerated antennae that are usually sexually size-dimorphic. We investigated the relationship between antenna morphology and sexual selection in the species Stenurella melanura (L.) in which males on average have antennae that are 13% longer than those of females. Males and females aggregate at flowers near oviposition sites for feeding during June-August. We sampled both copulating and single individuals at these sites. Fluctuating asymmetry (a measure of developmental instability) in antennae was considerably larger than in tibia and elytra and males had larger degrees of asymmetry in their antennae than females. Mated individuals did not differ from unmated individuals with respect to any of three size variables, but antennal asymmetry was smaller in mated individuals of both sexes. When two males were released with a female on a flower, males with symmetric antennae more often won the fight over the female than expected by chance. When two females and a male were released on a flower, the male more often preferred the female with more symmetric antennae than expected by chance. These results suggest that antennal symmetry, but not length, is currently under sexual selection.Copyright 1997 The Association for the Study of Animal Behaviour

Journal Article↗
PubMed2001

The association between daily mortality and ambient air particle pollution in Montreal, Quebec. 2. Cause-specific mortality.

This study was undertaken to determine whether variations in concentrations of particulates in the ambient air of Montreal, Quebec, during the period 1984 to 1993, were associated with daily variations in cause-specific daily mortality. Fixed-site air pollution monitors in Montreal provided daily mean levels of various measures of particles and gaseous pollutants. Total sulfate was also measured daily (1986-1993) at a monitoring station 150 km southeast of the city (Sutton, Quebec). We used coefficient of haze (COH), extinction coefficient, and sulfate from the Sutton station to predict fine particles and sulfate from fine particles for days that were missing. We estimated associations between cause-specific mortality and PM(2.5), PM(10), predicted fine particles and fine sulfate particles, total suspended particles, coefficient of haze, extinction coefficient, and total sulfate measured at the Sutton station. We selected a set of underlying causes of death, as recorded on the death certificates, as the endpoint and then regressed the logarithm of daily counts of cause-specific mortality on the daily mean levels for the above measures of particulates, after accounting for seasonal and subseasonal fluctuations in the mortality time series, non-Poisson dispersion, weather variables, and gaseous pollutants. We found positive and statistically significant associations between the daily measures of ambient particle mass and sulfate mass and the deaths from respiratory diseases and diabetes. The mean percentage change in daily mortality (MPC), evaluated at the interquartile range for pollutants averaged over the day of death and the preceding 2 days, for deaths from respiratory diseases was MPC(COH)=6.90% (95% CI: 3.69-10.21%), MPC(Predicted PM2.5)= 9.03% (95% CI: 5.83- 12.33%), and MPC(Sutton sulfate)=4.64% (95% CI: 2.46-6.86%). For diabetes, the corresponding estimates were MPC(COH)=7.50% (95% CI: 1.96-13.34%), MPC(Predicted PM2.5)=7.59% (95% CI: 2.36-13.09%), and MPC(Sutton sulfate)=4.48% (95% CI: 1.08-7.99%). Among individuals older than 65 years at time of death, we found consistent associations across our metrics of particles for neoplasms and coronary artery diseases. Associations with sulfate mass were also found among elderly persons who died of cardiovascular diseases and of lung cancer. These associations were consistent with linear relationships. The associations found for respiratory diseases and for cardiovascular diseases, especially in the elderly, are in line with some of the current hypotheses regarding mechanisms by which ambient particles may increase daily mortality. The positive associations found for cancer and for diabetes may be understood through a general hypothesis proposed by Frank and Tankersley, who suggested that persons in failing health may be at higher risk for external insults through the failure of regulating physiological set points. The association with diabetes may be interpreted in light of recent toxicological findings that inhalation of urban particles in animals increases blood pressure and plasmatic levels of endothelins that enhance vasoconstriction and alter electrophysiology. Further research to confirm these findings and to determine whether they are causal is warranted.

Aged↗
PubMed2002

Management of chronic hepatitis C and prevention of hepatocellular carcinoma.

Hepatitis C virus (HCV) infection is responsible for more than a half of the cases of chronic viral hepatitis in Japan. About 20% of patients who are chronically infected with the virus develop cirrhosis about 20-30 years after the infection, with hepatocellular carcinoma developing in about 5% of patients a year. The only drug that effectively reduces the virus is interferon, but complete eradication of the virus can be obtained in only 30%-40% of treated patients. Reevaluation of the predictive factors to eradicate the virus by 24-week interferon therapy showed that the genotype other than 1b, a low virus load, and multiple amino acid substitutions in the interferon sensitivity determining region (ISDR) of genotype 1b are statistically significant predictive factors. Amino acid substitution in the PePHD domain of the E2 protein was rare and was unrelated with the outcome of interferon therapy. The fluctuation of the virus titer measured by branched DNA during a 2-year observation period was less that 10-fold in most patients, and amino acid substitutions in the ISDR were rare in such patients, suggesting that one point measurement of these parameters may be useful to select candidates for interferon therapy. A comparison of patients treated with interferon and untreated patients from the viewpoint of cancer prevention showed only a slight decrease in the risk of treated patients developing hepatocellular carcinoma. However, patients who showed normal alanine amino-transaminase (ALT) irrespective of virus clearance showed a significantly reduced risk of liver carcinogenesis. Similarly, a retrospective study to evaluate the long-term preventive effect of glycyrrhizin on hepatocellular carcinoma development showed that the therapy was effective in lowering the ALT value and in preventing liver carcinogenesis.

Adult↗
PubMed1988

Time dependent zinc distribution in the development of the BW7756 murine hepatoma.

The Zn levels in selected tissue types were measured in a study of the BW7756 murine hepatoma utilizing 65Zn as a tracer. The total body burden and individual tissue activities (including tumor) were recorded at predetermined stages of tumor growth and directly compared to those obtained from normal (healthy) animals. 65Zn fluctuations observed with disease progression were correlated to the growth curve of the carcinoma. Normalization of individual tissue activities to the total body activity, the control of geometry and lack of significant attenuation of the accompanying gamma ray are unique advantages in the use of this isotope.

Animals↗
PubMed1991

Evaluation of patient-controlled analgesia (PCA) versus PCA plus continuous infusion in postoperative cancer patients.

The benefits of two dosing methods, patient-controlled analgesia (PCA) with morphine sulfate (MS) alone and PCA plus continuous infusion of morphine sulfate (PCA + CI) were clinically evaluated in a randomized, single-blinded study of 30 adult abdominal surgery patients. Doses were adjusted based on pain and sedation ratings. Respirations, pulse, blood pressure, pain and sedation ratings were assessed. Subjects rated their pain twice daily using a visual analog scale for 72 hr postoperatively. The subjects reported pain relief with both dosing regimens. No statistically significant differences between the groups were found in pain and sedation ratings, or length of time using the device, with the exception of a higher amount of MS used on postoperative day two by the infusion group (p less than 0.003). There seems to be a trend for the PCA + CI group to have less fluctuation in sedation between days and better pain control (as demonstrated by verbal and visual analog pain scores) on the third postoperative day. Statistical significance was not found, however. PCA plus continuous infusion of MS may be a beneficial approach to the management of postoperative pain in selected patients; studies to identify these patients need to be done.

Analgesia, Patient-Controlled↗
PubMed2005

The microbial experience of environmental phosphate fluctuations. An essay on the possibility of putting intentions into cell biochemistry.

We present a model of microbial information processing that contains characteristic features of the phenomenon of physiological adaptation. The backbone of the model is the "adaptive event" in which energy-converting subsystems of the cell interact with the changing environment. In this process, the subsystems pass, via an adaptive operation mode, from one adapted state to the next. An adaptive operation mode takes place when an adapted state is disturbed by an environmental alteration. These two manifestations of an adaptive event were differently treated in the simulation, based on an application of linear irreversible thermodynamics to the energy transduction of adaptive subsystems. In adapted states, the conductivity coefficients of the flow-force relationships employed remained constant, whereas during an adaptive operation mode, these coefficients were altered in a directional manner during the simulation. An example dealing with the complex relationship between phosphate uptake and cyanobacterial growth is given. In this example, the simulation of adapted states of two subsystems of the incorporating machinery, namely the phosphate carrier in the cell membrane and the F-ATPase in the thylakoid membrane, was in accordance with the measured uptake kinetics, and when fixed, predetermined conductivity coefficients were used. In the adaptive operation mode, however, the simulated behavior was in agreement with experimental observations when the program was able to "interpret" its own performance in the light of environmental phosphate fluctuations, experienced by the cell in the past, and to reconstruct the two subsystems according to this interpretation. Via transitions between adapted states and adaptive modes, information is transferred from one adaptive event to the next: the latter "inherits" the results of former interpretations. By appropriating them selectively, it is entering into a future in which its own interpretation is passed on to the following adaptive event. The model is discussed with respect to the concept of autopoiesis.

Adaptation, Biological↗
PubMed2005

Spatio-temporal cholinergic modulation in cultured networks of rat cortical neurons: evoked activity.

We studied the effects of carbachol, a cholinergic agonist, on extracellularly evoked firing of networks in mature cultures of rat cortical neurons, using multi-electrode arrays to monitor the activity of large numbers of neurons simultaneously. These cultures show evoked burst firing which propagates through dense synaptic connections. When a brief voltage pulse was applied to one extracellular electrode, spiking electrical responses were evoked in neurons throughout the network. The response had two components: an early phase, terminating within 30-80 ms, and a late phase which could last several hundreds of milliseconds. Action potentials evoked during the early phase were precisely timed, with only small jitter. In contrast, the late phase characteristically showed clusters of electrical activity with significant spatio-temporal fluctuations. The late phase was suppressed by applying a relatively small amount of carbachol (5 microM) in the external solution, even though the spontaneous firing rate was not significantly changed. Carbachol increased both the spike-timing precision and the speed of propagation of population spikes, and selectively increased the firing coincidence in a subset of neuron pairs in the network, while suppressing late variable firing in responses. Hence, the results give quantitative support for the idea that cholinergic activation in the cortex has a general role of focusing or enhancing significant associative firing of neurons.

Animals↗
PubMed2004

Mood swings in patients with anxiety disorders compared with normal controls.

BACKGROUND: About 70-80% of patients with anxiety syndromes suffer from depression. Mood variability including hypomania, cyclothymia and hyperthymia have been described in 40-50% of patients with depression. There is an emerging literature that such variability could also characterize anxiety disorders. The aim of this study was to visually document and quantify mood variability in patients with anxiety disorders. METHODS: Twenty patients with anxiety disorders and 22 normal control subjects completed two visual analogue scales (VAS) on depressed mood and high mood, twice per day for 14 days. The Beck Depression Inventory and the Altman Self-Rating Mood Scale were used for concurrent validity. RESULTS: On the VAS, patients showed higher levels of depressed and high moods, and greater mood variability than the controls. Variability of depressed and high moods was highly correlated. LIMITATIONS: This was a relatively small sample from a single center. Patients were selected by convenience and were under treatment. The control subjects were not interviewed. CONCLUSIONS: Subsyndromal mood variability in patients with anxiety disorders can be visually depicted and quantified. The mood variability of patients with anxiety disorders who also complain of mood swings is greater than the mood fluctuations described by normal subjects.

Adult↗
PubMed2003

The menopausal transition: characteristics and management.

The menopausal transition is a complex period in a woman's life, reflecting ovarian ageing and concomitant hormonal changes, in addition to social and metabolic changes. These changes, in turn, influence the signs and symptoms common to this period. Symptoms which are influenced by the hormonal fluctuations occurring during the menopausal transition include vasomotor symptoms and vaginal dryness; others are breast tenderness, poor sleep and pre-menstrual dysphoria. Hormonal therapy has been shown to be first-line therapy for many of these symptoms. Other types of pharmacotherapies may be helpful, including selective serotonergic uptake inhibitors for vasomotor symptoms. Characteristic signs of the menopausal transition include abnormal uterine bleeding, best managed with hormonal pharmacotherapy; diminishing bone mineral density, which may warrant diagnostic intervention, and may benefit from dietary and lifestyle modifications; and increased body-mass index and worsening lipid profile, which also may benefit from dietary and lifestyle modifications.

Cardiovascular Diseases↗
PubMed1987

Characterization of the channel properties of a neuronal acetylcholine receptor reconstituted into planar lipid bilayers.

An alpha-toxin-binding membrane protein, isolated from the head and thoracic ganglia of the locus (Locusta migratoria), was reconstituted into planar lipid bilayers. Cholinergic agonists such as acetylcholine, carbamylcholine, and suberyldicholine induced fluctuations of single channels, which suggests that the protein represents a functional cholinergic receptor channel. The antagonist d-tubocurarine blocked the activation of the channels, whereas hexamethonium had only a weak effect; similar properties have been described for nicotinic insect receptors in situ. The channel was selectively permeable to monovalent cations but was impermeable to anions. The conductance of the channel (75 pS in 100 mM NaCl) was independent of the type of agonist used to activate the receptor. Kinetic analysis of the channel gating revealed that, at high agonist concentrations (50 microM carbamylcholine), more than one closed state exists and that multiple gating events, bursting as well as fast flickering, appeared. At very high agonist concentrations (500 microM carbamylcholine), desensitization was observed. Channel kinetics were dependent on the transmembrane potential. Comparing the conductance, the kinetics, and the pharmacology of nicotinic acetylcholine receptor from insect ganglia and fish electroplax reconstituted into bilayers revealed obvious similarities but also significant differences.

Animals↗