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PubMed2003

Physical sports activity during leisure time and dietary intake of foods and nutrients in a large Spanish cohort.

This study evaluated the dietary pattern of foods and nutrients according to levels of vigorous leisure time physical activity (PA) assessed at recruitment within the Spanish cohort of the European Prospective Investigation on Cancer (EPIC) study (37,287 healthy volunteers with complete information). We used a validated PA questionnaire (PAQ) to measure the weekly frequency and duration of different kinds of sport activities. For dietary assessment, we used a validated diet history questionnaire that included all items consumed with a frequency of at least twice a month. We tested differences in food and nutrient intake according to PA duration by means of both an analysis of variance and an analysis of covariance adjusted for confounding factors. Linear increases or decreases in food and nutrient intake across PA levels were tested by means of a regression analysis. Only 11% of men and 6% of women performed at least 3 hours/week of intense PA, which is similar to current recommendations. Overall, main nutrient and total energy intakes were similar across different PA levels (<2% change in total energy intake between extreme PA categories). However, the intake of some foods and vitamins did significantly (p .05) increase as PA increased. The average gender-weighted percentage change in the intake of food and vitamins increased when moving from the lowest levels of PA to the highest. There was an increase in the intake of the following: 15.9% in vegetables, 6.7% in fruit, 9% in fish, 5.6% in dairy products, 10% in vitamin C, 5.9% in vitamin E, 7.2% in retinol, 19.7% in total carotene, 40.1% in alpha-carotene, 20.4% in beta-carotene, 11.2% in licopene, and 26.1% in lutein. BMI, which was above average for the cohort (mean +/- SD: 28.4 +/- 4.2), decreased steadily when PA increased. To sum up, in this large Spanish cohort, the differences in dietary intake relative to levels of PA were not found either in the amount of total energy consumed nor in the number of main macronutrients but rather in the intake of certain foods which, while having very little or moderate caloric content, are very rich in highly bioactive elements such as vitamins and provitamins.

Adult↗
PubMed1993

The time of administration of 3'-azido-3'-deoxythymidine (AZT) determines its host toxicity with possible relevance to AZT chemotherapy.

3'-Azido-3'-deoxythymidine (AZT) is the drug most widely used in the treatment of AIDS. Its major drug-related toxicity is bone marrow suppression, which limits the dose of AZT that can be used. It is essential that AZT be phosphorylated for antiviral effect. We have recently demonstrated that thymidine kinase (TK), the initial enzyme in AZT anabolism, follows a circadian pattern in rat bone marrow. The present study was undertaken to determine whether AZT toxicity is related to the time of its administration and whether the variation in toxicity is correlated with the circadian variation in TK activity. Male Sprague-Dawley rats were housed under standardized conditions of light and dark (lights on 0600 to 1800 and lights off 1800 to 0600) for 4 weeks. The animals were randomly divided into seven groups; six groups were administered AZT by intraperitoneal injection at the same dose of 750 mg/kg of body weight at various times (0400, 0800, 1200, 1600, 2000, and 2400), and one group was used as a control. AZT-related toxic effects, including bone marrow toxicity, differed significantly among the treatment groups, depending on the time of AZT administration (by analysis of variance and Cosinor analysis, P < 0.001). The least toxicity was observed in rats receiving AZT at 1600 (10 h after light onset [10 HALO], in late sleep span) and the greatest toxicity was observed in those injected at 0400 (22 HALO, in late activity span). To verify these results, we administered AZT by intraperitoneal injection at an approximately 50% lethal dose (1,500 mg/kg) to two groups of rats, one at 1200 (6 HALO, in the middle of the sleep span) and the other at 2400 (18 HALO, in the middle of the activity span). AZT lethality was significantly higher in rats receiving AZT at 2400 (18 HALO, in the middle of the activity span). Further statistical analysis demonstrated that the variation in AZT toxicity was correlated with the circadian variation in TK activity in bone marrow of the same species (peak activity at 0400 [22 HALO, in late activity span] and trough activity at 1600 [10 HALO, in late sleep span]), suggesting that the circadian variation in TK activity may be the biochemical basis for the observed circadian variation in AZT toxicity. These results may be useful in the design of improved AZT chemotherapeutic regimens.

Analysis of Variance↗
PubMed2003

MR imaging of reperfused myocardial infarction: comparison of necrosis-specific and intravascular contrast agents in a cat model.

PURPOSE: To compare T2-weighted and Gadomer-17- and bis-gadolinium mesoporphyrins-enhanced magnetic resonance (MR) images for distinguishing reversibly from irreversibly damaged myocardium in a cat model of reperfused myocardial infarction. MATERIALS AND METHODS: Twelve cats underwent 90 minutes of occlusion and 90 minutes of reperfusion of the left anterior descending coronary artery. After baseline T1- and T2-weighted MR images were obtained, Gadomer-17-enhanced and bis-gadolinium mesoporphyrins-enhanced T1-weighted images were sequentially obtained for 6 hours and 2 hours, respectively. After MR imaging, all cats were sacrificed for 2,3,5-triphenyltetrazolium chloride (TTC) histochemical tissue staining. Areas of abnormal signal intensity on T2-weighted and Gadomer-17-enhanced and bis-gadolinium mesoporphyrins-enhanced T1-weighted MR images were compared with the areas of infarction seen at TTC histochemical staining by using repeated-measures two-way analysis of variance, linear regression analysis, and Bland-Altman analysis. RESULTS: Mean areas of abnormally high signal intensity on T2-weighted and Gadomer-17-enhanced T1-weighted MR images (43.9% of the left ventricular surface area +/- 11.9 [SD] and 37.7% +/- 10.1, respectively) were significantly larger than the mean area of myocardial infarction at TTC staining (25.7% +/- 12.5) (P <.001). However, there was excellent correlation between the size of an enhancing area on bis-gadolinium mesoporphyrins-enhanced T1-weighted MR images and that of myocardial infarction at TTC staining (r = 0.916, P <.001). CONCLUSION: bis-Gadolinium mesoporphyrins-enhanced T1-weighted MR images accurately reflect the area of infarction, whereas the size of infarction is overestimated on T2-weighted and Gadomer-17-enhanced T1-weighted MR images, which seem to depict the periinfarct area as well as the infarct area.

Analysis of Variance↗
PubMed2004

A comparative study of variables that have an impact on noncancer end-of-life diagnoses.

By way of analysis of variance, this secondary analysis compared three groups of noncancer home hospice patients (AIDS, amyotrophic lateral sclerosis [ALS],and other) for psychological correlates of adaptation and well-being, pain, and physical function, as measured by the Life Closure Scale (LCS), the Affect Balance Scale, the McGill-Melzack Pain Questionnaire Part I, and the Karnofsky Performance Status Scale. The sample included 10 AIDS patients (Group 1), 6 ALS patients (Group 2), and 5 patients with other noncancer, end-stage diseases (Group 3). A significant difference was found between Group 2 (ALS) and Group 3 (other) on the LCS, F(2, 18) = 4.3, p =.03. Scheffe and Duncan range post hoc tests and at test at the p</=.05 level (t9 = 4.1, p =.003) confirmed the finding. No significant group differences were found among the ALS, AIDS, and other groups in measures of psychological well-being, pain, and physical function.

Acquired Immunodeficiency Syndrome↗
PubMed2003

Analytic methods for questions pertaining to a randomized pretest, posttest, follow-up design.

Delineates 5 questions regarding group differences that are likely to be of interest to researchers within the framework of a randomized pretest, posttest, follow-up (PPF) design. These 5 questions are examined from a methodological perspective by comparing and discussing analysis of variance (ANOVA) and analysis of covariance (ANCOVA) methods and briefly discussing hierarchical linear modeling (HLM) for these questions. This article demonstrates that the pretest should be utilized as a covariate in the model rather than as a level of the time factor or as part of the dependent variable within the analysis of group differences. It is also demonstrated that how the posttest and the follow-up are utilized in the analysis of group differences is determined by the specific question asked by the researcher.

Analysis of Variance↗
PubMed2002

Response of liver and heart trace elements in rats to the interaction between dietary zinc and iron.

An analysis of the interaction between dietary iron (Fe) and zinc (Zn) was performed by using data from Sprague-Dawley rats in a 5 x 4 fully crossed factorially arranged experiment. The concentrations of 9 trace elements from the liver and 10 from the heart were determined and subjected to diverse statistical analyses and were classified by their response to the interaction between dietary Fe and Zn. The interaction was studied by using analysis of variance (ANOVA), discriminant analysis, and logistic regression to determine the direction of interaction; that is, did dietary Fe affect dietary Zn or did dietary Zn affect dietary Fe? The use of discriminant analysis allowed for using multiple parameters (rather than a single parameter) to determine possible interactions between Fe and Zn. Thus, two main levels of interaction were studied: the separate response of each tissue mineral and the response of some grouped minerals. The responses studied were the effect of dietary Zn on tissue trace element parameters, the effect of dietary Fe on the parameters, the effect of dietary Zn on combined (grouped) parameters, and the effect of dietary Fe on combined parameters. As determined by ANOVA, only three individual trace elements--liver Fe, Cu, and Mo--were significantly affected by the interaction between Fe and Zn. However, a broader interaction between Fe and Zn is revealed when groups of, rather than single, trace elements arestudied. For example, an interaction between dietary Fe and Zn affects the weighted linear combination of heart Ca, Cu, K, Mg, Mn, P, and Zn. This article presents the hypothesis that grouped parameters may be useful as status indicators. The complete dataset can be found at http://www.gfhnrc.ars. usda.gov/fezn.

Analysis of Variance↗
PubMed2002

Six-month comparison of powered versus manual toothbrushing for safety and efficacy in the absence of professional instruction in mechanical plaque control.

BACKGROUND: Reports suggest powered toothbrushing may provide some clinical benefit over manual tooth-brushing, but most studies have been of short duration with subjects trained in toothbrush use. The aim was to determine if the oscillating-rotating powered brush (PB) could safely provide clinical benefits over and above a manual brush (M) in subjects with no formal instruction or experience in powered brush use. METHODS: This 6-month, single-masked, parallel design, randomized clinical trial compared the PB with an American Dental Association (ADA)-accepted soft-bristle manual brush in a non-flossing gingivitis population (n = 157). Subjects were given written instructions but no demonstration on toothbrush use at baseline. Efficacy was assessed by changes in gingival inflammation, plaque, calculus, and stain, while changes in clinical attachment levels and recession measurements provided safety data. A prophylaxis was provided after baseline assessment. The 6-month plaque index (PI) was recorded immediately post-brushing after covert timing of the subjects, and correlation analyses were run to assess the relationship of brushing time to PI. Paired t tests, analysis of variance (ANOVA), and analysis of covariance (ANCOVA) were used to assess within and between treatment group differences for PB (n = 76) versus M groups (n = 81). RESULTS: Measures of inflammation showed a statistically significant drop for both brushes at 3 and 6 months. Mean overnight full-mouth PI scores were significantly lower at 3 months for the PB (1.57) compared to the M group (1.80), P = 0.0013. Immediate post-brushing PI at 6 months was also significantly lower for the PB (1.10) versus M (1.39) (P= 0.0025). There was an overall negative correlation for PI and brushing time (r = -0.377, P= 0.0001). Mean calculus index (CI) scores were lower for the PB at 3 (P= 0.0304) and 6 months (P = 0.0078), while no significant differences in stain were observable. Clinical attachment level and recession measurements showed no significant between-group changes from baseline for either brush on canine teeth or on teeth with recession at baseline. CONCLUSION: The oscillating-rotating toothbrush safely provides clinical benefits in plaque and calculus reduction over a manual brush even in subjects with no formal oral hygiene instruction.

Adolescent↗
PubMed2000

Smoking cessation counseling with pregnant and postpartum women: a survey of community health center providers.

OBJECTIVES: This study assessed providers' performance of smoking cessation counseling steps with low-income pregnant and postpartum women receiving care at community health centers. METHODS: WIC (Special Supplemental Nutrition Program for Women, Infants, and Children) program staff, obstetric clinicians, and pediatric clinicians at 6 community health centers were asked to complete surveys. Smoking intervention practices (performance), knowledge and attitudes, and organizational facilitators were measured. Factors associated with performance were explored with analysis of variance and regression analysis. RESULTS: Performance scores differed significantly by clinic and provider type. Providers in obstetric clinics had the highest scores and those in pediatric clinics had the lowest scores. Nurse practitioners and nutritionists had higher scores than other providers. Clinic type, greater smoking-related knowledge, older age, and perception of smoking cessation as a priority were independently related to better counseling performance. CONCLUSIONS: Mean performance scores demonstrated room for improvement in all groups. Low scores for performance of steps beyond assessment and advice indicate a need for emphasis on the assistance and follow-up steps of national guidelines. Providers' own commitment to helping mothers stop smoking was important.

Adult↗
PubMed2003

Full pedigree quantitative trait locus analysis in commercial pigs using variance components.

In commercial livestock populations, QTL detection methods often use existing half-sib family structures and ignore additional relationships within and between families. We reanalyzed the data from a large QTL confirmation experiment with 10 pig lines and 10 chromosome regions using identity-by-descent (IBD) scores and variance component analyses. The IBD scores were obtained using a Monte Carlo Markov Chain method, as implemented in the LOKI software, and were used to model a putative QTL in a mixed animal model. The analyses revealed 61 QTL at a nominal 5% level (out of 650 tests). Twenty-seven QTL mapped to areas where QTL have been reported, and eight of these exceeded the threshold to claim confirmed linkage (P < 0.01). Forty-two of the putative QTL were detected previously using half-sib analyses, whereas 46 QTL previously identified by half-sib analyses could not be confirmed using the variance component approach. Some of the differences could be traced back to the underlying assumptions between the two methods. Using a deterministic approach to estimate IBD scores on a subset of the data gave very similar results to LOKI. We have demonstrated the feasibility of applying variance component QTL analysis to a large amount of data, equivalent to a genome scan. In many situations, the deterministic IBD approach offers a fast alternative to LOKI.

Analysis of Variance↗
PubMed2005

How short-term transdermal treatment of men with 7-oxo-dehydroepiandrosterone influence thyroid function.

Dehydroepiandrosterone may influence thyroid function. Its metabolite, 7-oxo-dehydroepiandrosterone, a precursor of immunomodulatory 7-hydroxylated metabolites and thermogenic agent, belongs to candidates of steroid replacement therapy. The question was addressed whether its application does influence laboratory parameters of thyroid function. 7-Oxo-dehydroepiandrosterone in the form of emulgel, 25 mg/day, was applied transdermally to 21 healthy men for 8 consecutive days. Morning blood was collected before the treatment (Day 0, Stage 1), during treatment (Day 5, Stage 2), on the first day after the last administration (Day 9, Stage 3), one week (Day 16, Stage 4), and 9 weeks (Day 72, Stage 5) after treatment termination. The levels of thyrotropin, free thyroxine and triiodothyronine, dehydroepiandrosterone, its sulfate and its 7-hydroxyepimers were measured. The changes were evaluated by analysis of variance and correlation analysis. During treatment a significant rise of 7beta-hydroxy-dehydroepiandrosterone was observed, which persisted 1 week after treatment termination. No changes were observed in dehydroepiandrosterone and its sulfate. Though a slight but significant rise of TSH and of both thyroid hormones occurred during treatment, its levels soon returned to the basal values. It was concluded that treatment of 7-oxo-dehydroepiandrosterone affects the thyroid parameters only temporarily and that it provides a considerable persistent amount of 7beta-hydroxy-dehydroepiandrosterone.

Administration, Cutaneous↗
PubMedDate not supplied

Midfacial morphology of Koreans with class III malocclusions investigated with finite-element scaling analysis.

The spheno-ethmoidal model of midfacial retrognathia suggests that deficient chondrocytic proliferation in the anterior cranial base is associated with inadequate anterior translation of the midfacial complex resulting, for example, in Class III malocclusions. The purpose of this study was to determine whether the morphology of the midface differed in subjects of diverse ethnic origin exhibiting features associated with Class III malocclusions. Lateral cephalographs of 142 children of Korean or European American descent aged between 5 and 11 years were compared. The cephalographs were traced and subdivided into seven age- and sex-matched groups. Average geometries, scaled to an equivalent size, were generated using Procrustes superimposition and subjected to analysis of variance (ANOVA). Graphical analysis using a color-coded finite-element scaling analysis (FESA) program was used to localize differences in morphology. Results indicated that the mean Korean and European American midfacial configurations differed statistically (P < 0.01), and this difference was maintained at most, but not all, age-wise comparisons. Comparing Korean and European American Class III midfacial configurations for local size-change, FESA analysis revealed that while local increases in size were apparent in the posterior palatal regions, the Korean anterior nasal spine regions were generally smaller. For shape-change, the Korean and European American midfacial configurations were predominantly isotropic. Therefore, heterogeneity in appearance may be influenced by morphological variation of the midfacial complex in subjects of diverse ethnic origin, but features of the anterior cranial base may contribute also to the prevalence and severity of Class III malocclusions in Koreans. Moreover, perturbations in endochondral mechanisms of cranio-mandibular growth, and not maxillary intramembranous methods, may be implicated in the etiology of Class III malocclusions in South East Asians.

Age Factors↗
PubMed2000

Leukocytosis is proportional to HELLP syndrome severity: evidence for an inflammatory form of preeclampsia.

BACKGROUND: We investigated the possibility that HELLP syndrome is in part a systemic inflammatory response. METHODS: We evaluated total white blood cell (WBC) counts of all patients with severe preeclampsia with and without HELLP syndrome admitted to our hospital between 1995 and 1997. Patients were grouped by diagnosis and timing of platelet nadir. Analysis of variance and regression analysis were used for data analysis. RESULTS: Of 177 patients, 91 had HELLP syndrome, and 86 had severe preeclampsia alone. The WBC counts were significantly higher in patients with HELLP syndrome (12.5 +/- .442 x 10(9)/L) than in patients with severe preeclampsia (10.3 +/- .288 x 10(9)/L). Regression analysis showed that platelet counts varied inversely with WBC counts. Also, patients with class I HELLP syndrome had significantly higher WBC counts than patients with other classes of HELLP syndrome. CONCLUSION: The finding of an association between increasing leukocytosis and worsening thrombocytopenia early in the course of HELLP syndrome supports the hypothesis that it may represent an inflammatory process.

Analysis of Variance↗
PubMed2003

Early clinical results from the use of 5% potassium nitrate in polycarboxylate cement for biological treatment of reversible pulpitis.

UNLABELLED: The aim of the present study was to obtain immediate and early clinical results from the use of 5% potassium nitrate (KNO3) in polycarboxylate cement for biological treatment of reversible pulpitis. MATERIAL AND METHODS: The method was applied in 140 teeth, mostly premolars and molars, with a clinical diagnosis of reversible pulpitis and indications for biological treatment of the inflamed dental pulp by means of indirect pulp capping. All teeth had clinically healthy periodontium and no non-carious lesions of the hard dental tissues. The study sample consisted of 127 patients aged between 16 and 40 years. The control group included 92 teeth in 78 patients, which were treated by a calcium hydroxide liner. The follow-up examinations were conducted 24 hours after treatment and on day 3 for the immediate results, and on days 7, 14, 30, and 90 for the early clinical results assessing the functional condition of the teeth, presence of thermal stimulus-induced pain and the measurements from the electric pulp vitality tests. The results were analysed with the analysis of variance and graphic analysis. RESULTS: The immediate and early clinical results of the biological treatment of reversible pulpitis with 5% KNO3 in polycarboxylate cement show that pain as a symptom of the initial inflammatory process in the dental pulp is rapidly and effectively relieved, leaving the treated teeth in good functional condition. The comparison of the measurements from the electric pulp tests of all teeth reveals a statistically significant difference (u = 8.51; P < 0.001) in favour of the group treated with potassium nitrate and polycarboxylate cement. CONCLUSIONS: 1. The immediate and early clinical results of our study suggest that treating reversible pulpitis with 5% KNO3 in polycarboxylate cement has an a very good analgesic action 2. The normal electrical excitability of the treated teeth is restored faster than that in the teeth treated by calcium hydroxide-based materials (P < 0.001).

Adolescent↗
PubMed1985

Urinary adenylate kinase activity as a predictor of renal allograft crises.

We examined data on adenylate kinase (EC 2.7.4.3) activity and other clinical chemical values from patients with renal transplants by analysis of variance and discriminant analysis, using various combinations of variables in an attempt to find a predictor of transplant rejection. Some typical data are presented. We conclude that the combination of urinary adenylate kinase and creatinine clearance is the best predictor for identifying patients with transient or destructive renal transplant crises.

Adenylate Kinase↗
PubMed1971

[Electrical picture of the brain under increased respiration in children. Studies on the structure of hyperventilation and its value as a provocation method in clinical electroencephalography in a model of multivariate analysis using electronic data processing].

In clinical electroencephalography, hyperventilation is the most used method of activation. However, knowledge of the conditions of hyperventilation with regard to their effects on the EEG is so far rather undifferentiated. For this reason the effects of hyperventilation in 1109 children are examined in this paper based on clinical and electroencephalographic parameters of a data configuration with a large number of criteria and the results obtained are calculated with the aid of electronic data processing. The statistical methods of examination were frequency and significance investigations by chi 2 tests, multifactorial analysis of variance, multiple regression analysis of influencing quantities, and determination of the reliability of the quantitative method of evaluation. New knowledge on group-statistical validity was obtained with this multivariant analysis and it was thus possible to extend the value of hyperventilation as a method of provocation in clinical electroencephalography. The increase in knowledge is based in particular on the facts that the hyperventilation effects are practically independent of sex, they do not require the consideration of certain age related development modalities of the EEG, they are diagnostically significant as regards unspecific changes of the bioelectrical activity, and they make a differentiated consideration with reference to their strength necessary, which results in 4 types of forms of changing the EEG spectrum. In addition to this, a recurrence of EEG changes was observed after the HV effect proper had faded, and the term "Reprise" is suggested for this and its clinico-encephalographic importance discussed. It was also found that occipital maxima dominate and that changes in frequency and amplitude require separate consideration. The influence of respiratory rate, tidal volume minute volume, alveolar CO2 tension, blood sugar and body weight on the strength of the effect of hyperventilation is not very significant. Mean controlled hyperventilation has proved useful to standardise arbitrary hyperventilation; an improvement could be achieved at the most by norming the respiratory rate. It was possible to prove that the applied method of non-mechanical quantitative EEG analyses had a high degree of accuracy and is consequently suitable for scientific investigations.

Adolescent↗
PubMed1983

Red cell creatine in term and preterm, adequate and small for gestational age newborns after normal pregnancy or risk conditions. II. Mathematical analysis of 12 risk conditions in relation to the creatine level at birth.

Univariate and multivariate analysis of variance and discriminant analysis were performed on newborns with respect to the level of red cell creatine at birth (cord blood) and 12 risk conditions occurring during the last trimester of gestation and birth. 111 of the 174 newborns studied had been at risk. The factor "small for gestational age" (SGA) showed to have a negative coefficient of discriminant function, i.e. it contributes to lower creatine values at birth. Other risks are shown to raise the creatine level. For "adequate for gestational age" (AGA) newborns "Rh-incompatibility", "toxoplasmosis", "premature and/or prolonged rupture of the membranes", "complications of the umbilical cord" and - to a minor degree - "pyelonephritis of the mother", "threatened premature labour", and "toxemia of pregnancy" were shown to be significant risks leading towards high red cell creatine concentrations in cord blood. For the SGA infants "preterm birth", "threatened premature labour", "green amniotic fluid" and "toxemia of pregnancy" were the most important risks relating to high creatine levels of red cells at birth.

Analysis of Variance↗
PubMed1997

Coagulation and fibrinolysis changes in normal pregnancy. Increased levels of procoagulants and reduced levels of inhibitors during pregnancy induce a hypercoagulable state, combined with a reactive fibrinolysis.

OBJECTIVE: To establish the physiologic changes in the coagulation and fibrinolytic systems during normal pregnancy and puerperium. STUDY DESIGN: One hundred and seventeen normal pregnant women were investigated in a longitudinal study involving five measurements: blood samples were collected at 10, 20, 30, 36 weeks and on the second day puerperium and were assayed for prothrombin time (PT expressed in INR), activated partial thromboplastin time (PTT), fibrinogen (FBG), antithrombin III activity (AT III), protein C activity (PC), protein S activity (PS), prothrombin fragments 1+2 (F1+2), type 1 plasminogen activator inhibitor activity (PAI) and tissue-plasminogen activator antigen (t-PA). Student t-test, One Way Analysis of Variance (ANOVA) and Bonferroni test were used for statistical analysis. P<0.05 (two tails) was assumed to indicate a significant difference. RESULTS: Fibrinogen concentrations were always increased with respect to controls (P<0.001), while protein S was always decreased, with values averaging 60% of those of controls from the 10th week of pregnancy onwards (P<0.001). Variance analysis showed a statistically significant increase with gestational age for procoagulant factors (INR: P<0.001; FBG: P<0.001), a reduction for anticoagulants (PC: P<0.0001; PS: P<0.0001), and a rise for F1+2 (P<0.0001). With regard to fibrinolysis, there was an increase both for t-PA (P<0.0001) and PAI-1 (P<0.0001) during pregnancy. The t-PA values were always comprised in the normal range. PAI-1 were increased with respect to control values starting from 31st week. The most significant variations in the procoagulants (expressed by PT and FBG) were recorded up to the 20th week (P<0.001); from the 30th week onwards, they remained stable until after the delivery. The same was true for protein S levels (P<0.001), except that the difference between the 10th and the 20th weeks was not statistically significant. The level of F1+2 gradually increased throughout pregnancy (P<0.001), and then fell in the puerperium (P<0.001). CONCLUSIONS: The parameters showing the greatest variation during pregnancy were PT, FBG, PS, F1+2 and PAI-1. The existence of a hypercoagulable state in pregnancy was suggested by the increased levels of F1+2.

Adult↗