The impact of Ibero-American science on global bioethical thinking

The bioethics research conducted in Ibero-American countries has been very much restricted to its own realm. The aim of this study was to perform a bibliometric evaluation of bioethics papers by authors affiliated with Ibero-American institutions, and to determine how their work influences global bioethics literature. We performed a literature search in the Web of Science Core Collection (WoS CC) and Scopus. We identified a total of 5,975 documents, of which 84.3% were articles, 11.6% reviews and 4.1% book chapters. The median number of citations per paper was higher in English-language journals. Only 10 articles published between 2010 and 2019 in peer-reviewed bioethics journals and produced exclusively by authors from Ibero-American institutions garnered more than 15 citations. Our study suggests that if researchers from Ibero-American institutions want to influence global bioethical thinking, they must make the required leap in quality to be able to publish in high-quality bioethics and mainstream journals.

The Vatican Opinion on Gender Theory

This article is a reasoned response to the article by Timothy F. Murphy, recently published in the prestigious journal Bioethics, on the supposed opposition between the views of the Catholic Church and what he calls "contemporary science" in relation to certain anthropological issues linked to the gender perspective. To point to "the Vatican" as anchored in an unscientific and anachronistic position, using the term contemporary science to which he attributes a unanimous representation of current scientific thinking on the subject is, in our view, unfounded and completely unacceptable. In his reflection, he does not adequately distinguish between intersex and transgenderism, two clearly different realities with different needs. The author defends the obsolescence of the binary sex/gender model that, in his view, "betrays human sexuality." Furthermore, he does so without providing a plausible justification or a definition of human nature that is able to support the plurality and indeterminacy of sexual conditions, without falling back on untenable dualisms or relativism devoid of scientific objectivity. In our response, we highlight how the dialogue between Faith and Reason, as developed in the recent Magisterium of the Catholic Church, is essential to explain nature, the human being and, in general, all creations. Finally, contemporary science does not provide a monolithic and unquestionable view of the nature of human beings and their sexual identity, as the author claims, with many scientists confirming evidence of a binary human sexuality genetically and phenotypically determined.

Summary

This paper is a reasoned response to the supposed opposition between the views of the Catholic Church and "contemporary science" in relation to certain anthropological issues linked to the gender perspective.The dialogue between Faith and Reason, as developed in the recent Magisterium of the Catholic Church, is essential to explain nature, the human being and, in general, all creation, against the opinion of those who defend the obsolescence of the binary sex/gender model that, in their view, "betrays human sexuality".

The Use of NFP When Pregnancy Is Contraindicated?

The Sacred Congregation for the Doctrine of the Faith has declared the moral liceity of hysterectomy when certain medical criteria are met but does not exclude other options, "for example, recourse to infertile periods or total abstinence." Consequently, there may be couples who prefer to use natural family planning (NFP) methods. We shall refer to these in this article. The efficacy of NFP methods is determined by knowing the day of ovulation. To that end, three parameters are used: the presence and consistency of cervical mucus, measurement of the basal body temperature, and the determination of particular hormones in urine. Of the NFP methods used, the so-called sympto-thermal method seems to be the most effective. It has been concluded that the postovulatory or luteal phase of the female menstrual cycle is the safest time to avoid pregnancy if the couple has sexual intercourse during this period. Nevertheless, the use of NFP methods has limitations if the length of the cycles varies, there are fluctuations in the basal temperature, or when there are vaginal infections. Urinary hormone levels can also be altered by the use of antibiotics or psychotropic drugs. In general, however, it can be concluded that NFP methods, if used in the conditions mentioned herein, offer a high degree of reliability, similar to that of artificial contraceptive methods. Accordingly, if pregnancy must be avoided in the medical circumstances to which the Congregation for the Doctrine of the Faith refers, NFP methods can effectively replace hysterectomy, thereby circumventing the medical difficulties of this practice.

Summary

The Sacred Congregation for the Doctrine of the Faith has declared the moral liceity of hysterectomy when certain medical criteria are met but does not exclude other options, "for example, recourse to infertile periods or total abstinence." Consequently, there may be couples who prefer to use natural family planning (NFP) methods. We shall refer to these in this article. In general, it can be concluded that NFP methods, if used in the conditions mentioned herein, offer a high degree of reliability, similar to that of artificial contraceptive methods. Accordingly, if pregnancy must be avoided in the medical circumstances to which the Congregation for the Doctrine of the Faith refers, NFP methods can effectively replace hysterectomy, thereby circumventing the medical difficulties of this practice.

A multimodal intervention program to control a long-term Acinetobacter baumannii endemic in a tertiary care hospital

Background

Acinetobacter baumannii causes frequently nosocomial infections worldwide. Its ability to survive on dry surfaces facilitates its spread and the persistence of endemic situations, especially in the intensive care units (ICUs).

The objective of this paper is to describe a multicomponent intervention program designed to control a hyperendemic persistence of multidrug-resistant A. baumannii (MDR-Ab) and to characterize its impact.

Methods

Design: Quasi-experimental intervention study based on open cohorts.

Setting: Public tertiary referral centre. Period: January 2009–August 2017.

Intervention: multifaceted program based on environmental decontamination, hand hygiene, antimicrobial stewardship, contact precautions, active surveillance, weekly reports and regular meetings.

Analysis: joinpoint regression and interrupted time-series analysis.

Results

The intervention was successfully implemented. Through the study period, the compliance with contact precautions changed from 0 to 100% and with hand hygiene, from 41.8 to 82.3%. Between 2012 and 2016, the antibiotic consumption decreased from 165.35 in to 150.44 daily-defined doses/1000 patients-days in the ICU. The incidence density of MDR-Ab in the ICU was 10.9 cases/1000 patients-days at the beginning of the intervention. After this moment, the evolution of the incidence density of MDR-Ab was: between months 0 and 6°, it remained stable; between months 7° and 10°: there was an intense decrease, with an average monthly percentage change (AMPC) = − 30.05%; from 11° month until the end, the decrease was lighter but continuous (AMPC:-2.77%), achieving an incidence density of 0 cases/1000 patients-days on the 18° month, without any new case for 12 months. From the 30° month until the end of the study period, several little outbreaks of MDR-Ab were detected, all of them rapidly controlled. The strains of MDR-Ab isolated during these outbreaks were not clonally related with the previously endemic one, which supports its eradication from the environmental reservoirs.

Conclusion

The multicomponent intervention performed by a multidisciplinary team was effective to eradicate the endemic MDR-Ab.

Gestational Surrogacy: Current View

Surrogate motherhood is an assisted procreation practice by which a woman gestates an embryo with which she has no biological relationship on behalf of a contracting couple or individual, having to relinquish the child to them after its birth. This practice normally entails a financial remuneration for the pregnant woman; when this is not the case, it is called altruistic surrogacy. From a medical perspective, potential problems for the surrogate and for children born through this practice should be taken into account, especially the existence of possible disabilities in the child. The bioethical aspects are of most interest because the practice of surrogacy objectifies the expectant mother, by using her body for a purpose other than her own good, treating her as a commodity, as a thing. The same is true for the child because it makes him a disposable object, something that can be instrumentalized, similarly objectifying him.

The Conception of Synthetic Entities from a Personalist Perspective

Synthetic biology opens up the possibility of producing new entities not found in nature, whose classification as organisms or machines has been debated. In this paper we are focusing on the delimitation of the moral value of synthetic products, in order to establish the ethically right way to behave towards them. In order to do so, we use personalism as our ethical framework. First, we examine how we can distinguish between organisms and machines. Next, we discuss whether the products of synthetic biology can be considered organisms at all and assess what their moral value is and how should we behave towards them. Finally, we discuss the hypothetical case of synthetic humans.

Early Platelet-Collagen Interactions in Whole Blood and Their Modifications by Aspirin and Dipyridamole Evaluated by a New Method (Basic Wave)

It is shown that the supernatant of unstirred whole blood at 37° C, stimulated by 1 μg/ml of collagen for 10 sec, produces a rapid generation of pro and antiaggregatory compounds with a final proaggregatory activity which can be detected for more than 60 min on a platelet rich plasma (PRP) by turbidometric aggregometry. A reversible aggregation wave that we have called BASIC wave (for Blood Aggregation Stimulatory and Inhibitory Compounds) is recorded. The collagen stimulation of unstirred PRP produces a similar but smaller BASIC wave. BASIC’s intensity increases if erythrocytes are added to PRP but decreases if white blood cells are added instead. Aspirin abolishes “ex vivo” the ability of whole blood and PRP to generate BASIC waves and dipyridamole “in vitro” significantly reduces BASIC’s intensity in whole blood in every tested sample, but shows little effect in PRP.

Plasminogen Activator Inhibitors Type 1 and Type 2 and Plasminogen Activators in Amniotic Fluid during Pregnancy

Plasminogen activator inhibitor activity (PAI), PAI-1 and PAI-2 antigen, and other fibrinolytic parameters were evaluated in amniotic fluid during normal pregnancy and compared with that obtained in plasma of pregnant women. The results indicate the presence of both PAI-1 and PAI-2 in amniotic fluid during normal pregnancy. In amniotic fluid, PAI-1 antigen levels increased from 194 ± 109 ng/ml (first trimester) to 640 ± 396 ng/ml (third trimester) and PAI-2 antigen levels increased from 72 ± 57 ng/ml to 173 ± 97 ng/ml. In contrast, a decrease in tissue-type plasminogen activator (t-PA) antigen level was observed during pregnancy. The PAI-1 levels in amniotic fluid were significantly higher than the PAI-1 levels in plasma of women at a similar gestational age. However, PAI activity, measured using single chain t-PA, was lower in amniotic fluid than in plasma of normal pregnant women. The PAI activity/PAI-1 antigen ratio in amniotic fluid after activation by a denaturing agent increased from 0.003 ± 0.004 to 0.059 ± 0.018. These results indicate that high levels of PAI-1 are present in amniotic fluid and suggest that this PAI-1 is present in a latent form that can be reactivated, at least partially, by a denaturing agent.

Functional and Immunologic Protein S in Normal Pregnant Women and in Full-Term Newborns

Total and free protein S antigen and C4b-binding protein (C4bp) were determined by rocket immuno-electrophoresis, and functional protein S was assayed by a coagulation method, throughout pregnancy and normal puerperium and in a group of normal full-term newborns (FTN). The functional protein S assay is based on a modification of the APTT, using a mixture of test sample, protein S deficient plasma, activated protein C, phospholipids and calcium. This protein S functional assay is specific for protein S since the APTT prolongation by normal plasma was abolished by incubation of plasma with monospecific, rabbit antiprotein S IgG. The ratios of functional protein S/free protein S antigen in healthy men (n = 13) and women (n = 14) were 1.0 ± 0.13 (mean ± SD) and 1.03 ± 0.20, respectively. During pregnancy there is a decrease in functional protein S and a progressive decrease in total and free protein S antigen, with a functional/free protein S ratio of 0.75 ± 0.28 in the third trimester of pregnancy (n = 16). In early puerperium the functional protein S level was lower than the free protein S antigen level (ratio about 0.5). In the FTN group, the free protein S level was 39% and protein S activity was about 70% that of adults, with a functional/free protein S ratio of 1.84 ± 0.31. C4bp values were 23.5 ± 10.3% in the FTN group, and crossed immunoelectrophoresis showed that in this group the major protein S peak corresponded to free protein S. These results indicate that both in early puerperium and in FTN group, free protein S antigen may not be an adequate parameter for estimating of functional protein S activity. The decrease in functional protein S activity during early puerperium may be connected with the risk of developing thrombotic episodes during the postpartum period.

Influence of Some Plasma Fatty Acids on the Phospholipid Fatty Acid Pattern of Human Platelets – An “Ex Vivo” Experience

Some correlations between plasma and platelet fatty acids (FA) were evaluated “ex vivo” in 94 normal subjects.

The highest relationships between total FA from plasma and platelets were found for 18:1 (r = 0.74) and 18:2 (r = 0.67). Low correlations were obtained for free fatty acids (FFA). The most significant correlations between fatty acids esterifying plasma and platelet phospholipids were found for the 18:1 (r = 0.66); 18:2 (r = 0.74) and 20:5 (r = 0.66).

Our results suggest that the platelet phospholipid FA could be more easily modified by plasma variation in the FA composition of phospholipids than by variations in the plasma FA composition of the FFA fraction. In addition, the incorporation of FA from plasma into the platelet phospholipids “in vivo” may take place through an acylation-deacylation process and also by the incorporation of whole plasma phospholipid molecules into the platelets, probably through an exchange of plasma lipoproteins and platelets. Finally, arachidonic acid seems to have a different and selective way of incorporation into platelet phospholipids.

Inherited Fibrinolytic Disorder Due to an Enhanced Plasminogen Activator Level

A family with “in vitro” increased red-cell fall out from the blood clot was studied. One member of the family (JVM) had a clinical history of hemorrhages after minor trauma or dental extractions. Routine coagulation and platelet function were normal except for the fibrinogen level which was slightly low in several members. The antigenic as well as functional evaluation of factor XIII was within normal limits. No factor XIII inhibitors were present. An increase in the clot permeability index was observed in most family members.

The study of the fibrinolytic system showed an enhanced lysis of euglobulins, a normal plasminogen value, normal level of fibrin/ogen degradation products, normal fibrinolytic inhibitors, and an increase in the activity of the plasminogen activator. The activity of this activator was inhibited by an antiserum against tissue-type plasminogen activator. The t-pA inhibitor was in the normal range.

It is concluded that the family studied in this paper shows familial alteration in the fibrinolytic system due to an excess of plasminogen activator immunologically related to that in human tissue.

Dysfunctional Plasminogen in Full Term Newborn - Study of Active Site of Plasmin

The functional activity and active site of plasmin in full-term newborns have been studied and compared to those in adults in order to investigate the nature of the abnormality found in newborn plasminogen descried in a previous paper.

The functional activity of newborn plasminogen measured on chromogenic substrate was approximately 18% that of adult plasminogen when streptokinase was used as an activator and 12% when urokinase was used.

Proteolysis of newborn plasminogen by urokinase yielding a two-chain plasmin form occurred normally, but the incorporation of diisopropylphosphorofluoridate into the light chain of newborn plasmin was approximately 23% of that observed in the light chain of adult plasmin.

These observations suggest that the abnormality of full-term newborn plasminogen is located in the active site of the molecule.

“Ex Vivo” Influence of Fatty Acids from Plasma Cholesterol and Triglycerides on the Fatty Acid Pattern of Platelets

We have studied “ex vivo”, in 92 normal subjects, the influence of fatty acids (FA) that esterify plasma cholesterol and triglycerides on the fatty acid composition of phospholipids, triglycerides and free fatty acid fractions in platelets.

High and significant correlations (p <0.001) were found for some of the platelet phospholipid FA and the same FA that esterify plasma cholesterol [18:11 (r = 0.56); 18:2 (r = 0.71) and 20:5 (r = 0.42)] and plasma triglycerides [18:1* (r = 0.57) and 18:2 (r = 0.66)]. Some significant correlations were also found between some of the platelet triglyceride FA and the same FA that esterify plasma phospholipids [18:1 (r = 0.58)], triglycerides [18:1 (r = 0.51), 18:2 (r = 0.52)] cholesterol [18:1 (r = 0.44)] and plasma free fatty acids [18:1 (r = 0.39); 18:2 (r = 0.40)].

By evaluating these results in conjunction with those of an earlier study (1), it can be concluded that “ in vivo” the FA from different plasma lipid fractions and especially those esterifying the plasma cholesterol and phospholipid fractions, can influence the FA composition of platelet phospholipids in normal subjects. In trying to interpret the role played by plasma lipids in platelet lipids, it may be of interest to take into account the interrelationships found in this study.

Fibrinolytic Activity and Protein C in Preeclampsia

Various parameters of the fibrinolytic system and antigenic and functional protein C and its inhibitor were studied during normal pregnancy and in patients with preeclampsia.

The fast acting tissue-type plasminogen activator inhibitor level was found to increase progressively during normal pregnancy. This increase was more evident in cases of severe preeclampsia (p<0.05). No variations were observed in protein C levels in normal pregnancies but a reduction in protein C level was noted in patients with severe preeclampsia (p<0.01). In preeclampsia, the protein C inhibitor level was higher than in normal pregnancy; it was also higher in normal pregnancy when compared to the control group.

Role of Red Blood Cells in the Early Stages of Platelet Activation by Collagen

Red blood cells (RBC) increase the proaggregatory capacity of a cell-free supernatant obtained by stimulating platelet-rich plasma (PRP) samples with collagen (1 μg/ml) as measured by the BASIC wave; this effect increases with the number of RBC and is proportionally greater with a lower number of platelets or when lower collagen concentrations are used.

Aspirin (ASA) modifies the RBC behaviour in relation to their platelet-collagen interaction. This is demonstrated by the fact that when PRP and RBC obtained from the same subjects before and two hours after the ingestion of ASA (0.5 g) were mixed, it was found that non-AS A-RBC stimulate ASA-PRP, probably through a platelet cyclooxygenase independent pathway; ASA-RBC, however, stimulate non-ASA-PRP, but not ASA-PRP, which suggests that they may need an active platelet cyclooxygenase system for their action. This effect of ASA on RBC is not transient and was also observable 48 h after ASA ingestion. In addition, it was found that ASA-RBC greatly increase the activation of a mixture containing a small proportion of non-ASA-PRP in ASA-PRP, a situation that is expected to be encountered “in vivo” after ASA treatment. This effect of ASA-RBC on platelet activation may help to explain the sometimes contradictory clinical effect of aspirin as an antithrombotic drug.

Identification of High Molecular Weight Derivatives of Plasmic Digests of Cross-Linked Human Fibrin

Highly cross-linked human fibrin was digested with plasmin and the nine main components (labelled initially 1 to 9) were detected by sodium dodecyl sulfate polyacrylamide gel electrophoresis. The components of greater molecular weight, bands 1 and 2, which are identified with fragments Y dimer and Y-D (270,000 and 220,000) contain three subunits which are joined by disulphide bonds which originate from the α, β and γ-γ-chains of cross-linked fibrin. They show a reaction of partial identity against anti fibrinogen fragment D-sera and anti fibrinogen fragment E sera. Bands 3, 4 and 5 correspond to three species of fragment D-dimer and have molecular weights of 175,000,160,000 and 130,000. Each of these species differs in the size of the γ-γ-chain remnants, while all maintain the cross-link between the γ-γ-chains. The remnants of a and β-chains of cross-linked fibrin remain the same in all three species. The components of electrophoretic bands 6, 7 and 8 correspond to three fragments, each with a different molecular weight and with common antigenic components against anti fibrinogen fragment D-sera; these are called D6 (90,000), D7 (75,000) and D8 (65,000) and are formed by α- and β-chain remnants of equal molecular weight and by γ-chain remnants with a different molecular weight for each fragment. The last fragment to be identified, corresponding to electrophoretic band 9 (50,000 molecular weight) corresponds to fibrin fragment E. The present report is in agreement with previous studies of plasmin digestion of highly cross-linked fibrin, but differs from them in number of fragments D-dimer which appear during the digestion.

Alterations in the Coagulation and Fibrinolysis System in Pregnancy Labour and Puerperium, with Special Reference to a Possible Transitory State of Intravascular Coagulation during Labour

Various tests of hemostasis were carried out during pregnancy, labour and the puerperium in a group of 259 women. Determinations were carried out in the 1st, 2nd and 3rd trimesters, in the period of dilatation, the expulsion period, the period of expulsion of the placenta and the immediate postpartum period of labour and on each of the first 5 days of the puerperium. It was confirmed that during pregnancy there is an elevation of the fibrinogen degradation producs (FDP) levels with a proportional increase in the numbers of positive protamine sulfate and ethanol tests. The proportion of positive protamine sulfate and ethanol tests reaches a maximum in the expulsion of the placenta coinciding with the presence of soluble complexes heavier than fibrinogen as detected by polyacrylamide gel electrophoresis and by column chromatography.

All this indicates that there is a transitory intravascular coagulation produced during labour reaching its maximum at the time of birth and tending to become normalized in the first few days of the puerperium.

Heparin Stimulation of the Inhibition of Activated Protein C and other Enzymes by Human Protein C Inhibitor - Influence of the Molecular Weight of Heparin and Ionic Strength

The ability of unfractionated (UF) heparin and low-molecular-weight heparin (LMWH) to potentiate the inhibition of fibrinolytic and coagulation factors by protein C inhibitor (PCI) was studied. Inhibition of activated protein C (APC), urokinase plasminogen activator (uPA), tissue plasminogen activator (tPA), thrombin, factor Xa (Xa), factor XIa (XIa) and plasma kallikrein (KK) by PCI was found to be dependent on the size of the polysaccharide. In general, maximal stimulation was reached with UF heparin, except in the case of KK. Differences in heparin stimulation were more pronounced for thrombin, APC, uPA, tPA and XIa, whereas inactivation of Xa by PCI was less dependent on the presence of heparin, and kallikrein showed higher potentiation with LMWH than with UF heparin. The second-order rate constants for enzyme inhibition by PCI were strongly dependent on the ionic strength, and, in general, with an ionic strength higher than 0.15 the heparin stimulation of the inhibition reactions was drastically reduced. These results may explain the large discrepancies in the literature on the effect of heparin on the stimulation of enzyme inhibition by PCI. They also show that LMWH is less efficient in stimulating the PCI inhibition of APC, uPA and tPA, which could contribute to the antithrombotic effect of these enzymes.

Decreased Expression of PAI-2 mRNA and Protein in Pregnancies Complicated with Intrauterine Fetal Growth Retardation

An increase in plasma plasminogen activator inhibitors (PAIs), fundamentally PAI type 2 (PAI-2), has been described in normal pregnancy probably because the placenta is the main source of the high plasma levels of this protein. Although we have previously described plasmatic alterations of these inhibitors in pregnancies complicated with intrauterine fetal growth retardation (IUGR), no reports have been published about placental PAI-2 mRNA expression. In the present study, the placental PAI-2 expression determined in pregnancies complicated with IUGR and in severe preeclamptic patients was compared with that of normal pregnancies in order to identify the placental cell types expressing PAI-2 and to determine whether the production of PAI-2 is altered in placentas from IUGR. In situ hybridization analyses show that the syncytiotrophoblasts are the cells with the greatest PAI-2 expression in placenta. We report that the significant decrease in plasma and placental PAI-2 levels in IUGR groups is fundamentally due to a diminished expression of PAI-2 mRNA in placenta.

Quantification of Circulating Activated Protein C in Human Plasma by Immunoassays - Enzyme Levels are Proportional to Total Protein C Levels

We have developed a simple assay that measures the circulating activated protein C (APC) in plasma. The assay requires collection of duplicate blood samples, one in citrate plus heparin and the other in citrate plus inhibitors of the enzyme. In the heparin tube, APC reacts completely and irreversibly with its major plasma inhibitors, protein C inhibitor (PCI) and α1-antitrypsin (α1AT), and the complexes formed are measured by ELISAs. The amount of circulating APC is calculated from the difference between the total amount of complexed APC (sample in citrate plus heparin) and the amount of APC complexed in vivo (sample in citrate plus inhibitor). Over 95% of the APC added to blood collected with heparin was recovered in the assay. The assay can easily be performed in four hours, and had a detection limit of 0.1 ng/ml APC. The mean APC level in 18 protein C heterozygous members from seven kindreds was significantly lower (0.6 ± 0.3 ng/ml) than in 20 healthy controls (1.1 ± 0.3 ng/ml) (p <0.001), whereas the mean level in 10 non-affected members from the kindreds studied was 1.5 ± 0.3 ng/ml. In the group of 12 nonanticoagulated heterozygous protein C-deficient individuals, the three patients with a history of venous thrombosis had a mean APC level significantly lower than the nine asymptomatic members (p <0.01), both subgroups showing similar protein C levels. There was a significant correlation in all groups between the levels of APC and the levels of protein C antigen (r = 0.758, p <0.0001) and activity (r = 0.745, p <0.0001), which means that APC circulating levels are proportional to protein C levels and suggests that the protein C level is the limiting factor in the rate of protein C activation in vivo.

Studies on the Functionality of Newly Synthesized Fibrinogen after Treatment of Acute Myocardial Infarction with Streptokinase, Increase in the Rate of Fibrinopeptide Release

In 15 patients with acute myocardial infarction who received 1,500,000 U of streptokinase, the gradual appearance of newly synthesized fibrinogen and the fibrinopeptide release during the first 35 h after SK treatment were evaluated. At 5 h the fibrinogen circulating in plasma was observed as the high molecular weight fraction (HMW-Fg). The concentration of HMW-Fg increased continuously, and at 20 h reached values higher than those obtained from normal plasma. HMW-Fg represented about 95% of the total fibrinogen during the first 35 h. The degree of phosphorylation of patient fibrinogen increased from 30% before treatment to 65% during the first 5 h, and then slowly declined to 50% at 35 h.

The early rates of fibrinopeptide A (FPA) and phosphorylated fibrinopeptide A (FPAp) release are higher in patient fibrinogen than in isolated normal HMW-Fg and normal fibrinogen after thrombin addition. The early rate of fibrinopeptide B (FPB) release is the same for the three fibrinogen groups. However, the late rate of FPB release is higher in patient fibrinogen than in normal HMW-Fg and normal fibrinogen. Therefore, the newly synthesized fibrinogen clots faster than fibrinogen in the normal steady state.

In two of the 15 patients who had occluded coronary arteries after SK treatment the HMW-Fg and FPAp levels increased as compared with the 13 patients who had patent coronary arteries.

These results provide some support for the idea that an increased synthesis of fibrinogen in circulation may result in a procoagulant tendency. If this is so, the HMW-Fg and FPAp content may serve as a risk index for thrombosis.

Effect of Aspirin on Platelet Phospholipids

It was observed that the acetylsalicylic acid “in vitro” (final concentration 10−4 M) as well as “in vivo” (1 g of aspirin) caused a platelet phospholipids variation which basically consisted of:

1. A diminution of the phospholipids/proteins rate of 22%.

2. A reduction of sphingomyelin “in vivo” of 27.66% and “in vitro” of 16.82%.

3. An increase in phosphatidyl choline “in vivo” of 12.24% and “in vitro” 10.28%.

The possible effects that these changes might have on the platelet function are evaluated.

Changes in Human Amniotic Fluid Fibrinolytic Inhibitor Levels during Pregnancy

The amniotic fluid (AF) when incubated with the patient’s own plasma diminishes the lytic activity of the plasma. It is suggested that this inhibition is due to the presence of fibrinolytic inhibitors in the AF. The inhibitors rate increases as pregnancy advances. Evaluating these inhibitors in a group of 65 women before and after the 38th week of pregnancy, a higher rate of fibrinolytic inhibitors is found after the 38th week. The said differences are statistically significant. For the moment it does not seem that the increasing of the inhibitors in the last part of pregnancy might be used as a fetal maturity test.

Interaction of Plasma Kallikrein with Protein C Inhibitor in Purified Mixtures and in Plasma

The interaction between plasma kallikrein (KK) and protein C inhibitor (PCI) and the influence of KK on the complex formation between activated protein C (APC) and PCI was studied in purified systems as well as in plasma in order to assess the significance of these reactions in the plasma milieu. PCI complexed to KK (KK: PCI) or to APC (APC: PCI) was measured by sandwich ELISA’s using antibodies directed against each protein in the complexes. The formation of KK: PCI complexes assayed by this method paralleled the inhibition of KK amidolytic activity by PCI in purified system. Incubation of normal plasma (NHP) at 4 °C, which can induce prekallikrein activation due to cold activation, resulted in PCI inactivation and appearance of KK: PCI complexes. PCI activity fell to 35% of the NHp and 1.2 μ/ml of KK: PCI complex was formed. However, incubation of NHP at room temperature or of prekallikrein deficient plasma at 4 °C did not result in significant decrease of PCI activity. Thus the PCI inactivation was associated with prekallikrein activation and complexation to PCI following cold activation. Incubation of exogenous purified KK with NHP resulted in PCI inactivation and complexation with KK in a temperaturedependent manner. Addition of 2.8 μ/ml KK to plasma at 4 °C resulted in the inactivation of 55% of plasma PCI and the formation of 0.9 μ/ml KK: PCI which represents 21% of the KK added, whereas at 37 °C PCI was inactivated to 30% and only 0.30 μg/ml KK: PCI complexes were measured. These results indicate that PCI is a major KK inhibitor at 4 °C. At 37 °C, PCI accounted for aborfi 7% of the inhibition of the KK added. In separate experiments, following addition of 2.5 μg/ml APC to NHR more than 1 μg/ml of APC: PCI complex was formed in 3 h. When NHP was prior incubated with KK, PCI activity decreased to 10% of that of the normal plasma. Subsequent addition of APC to the plasma treated with KK resulted in formation of only 35 μg/ml of APC: PCI complex compared to 1,350 μg/ml when plasma was not previously incubated with KK. These results indicate that PCI could play a physiological role in the inhibition of plasma KK, and that, in turn, plasma KK can either complex to or inactivate plasma PCI. Thus, KK could modulate the PCI inhibition of APC in plasma.

Fibrinogen Valencia A New Case of Congenital Dysfibrinogenemia

A new case of dysfibrinogenemia is described, the proband had low fibrinogen level and a moderate hyperfibrinolysis. Attention is drawn to the florid hemorrhagic picture and its early presentation.

The family history showed a moderate hyperfibrinolysis.

It appeared that the cause of the dysfibrinogenemia was due to a deficient polymerization of the α chains of the fibrinogen.

It is not yet known if this is caused by a defective liberation of fibrinopeptides. Due to the peculiar characteristic of this case and in accordance with the international norms, we propose to call this dysfibrinogenemia “Fibrinogen Valencia.”

Contribution of Platelets to Increased Plasminogen Activator Inhibitor Type 1 in Severe Preeclampsia

Plasminogen activator inhibitor activity and antigen were evaluated in plasma, serum and platelet lysate in patients with severe preeclampsia (n = 12), and in normal pregnant women (n = 21). Other parameters, including β-thromboglobulin and platelet count, were also evaluated. A significant increase (p <0.05) in β-thromboglobulin was observed in platelet poor plasma of preeclamptic women when compared with that of normal pregnant women, and the platelet count was lower in the preeclamptic group than in the normal pregnant group. A significant increase in plasminogen activator inhibitor activity and antigen was observed in platelet poor plasma of the preeclamptic group as compared with normal pregnant women, whereas platelet lysate from preeclamptic women showed a significant decrease in both plasminogen activator inhibitor activity and antigen as compared with that of normal pregnant women. No correlation between β-thromboglobulin and plasminogen activator inhibitor type 1 antigen in platelet poor plasma was observed, but a significant inverse correlation (r = −0.78, p <0.05) between β-thromboglobulin in platelet poor plasma and plasminogen activator inhibitor-1 antigen in platelet lysate was obtained in preeclamptic patients. However, in platelet poor plasmas obtained from normal platelet rich plasmas activated with thrombin (0.1 IU/ml, 37° C, 1 min), an increase of about 300 ng/ ml in β-thromboglobulin was observed while the increase in plasminogen activator inhibitor was only 4 ng/ml. It is concluded that the contribution of platelet plasminogen activator inhibitor-1 to the increase in plasma plasminogen activator inhibitor-1 levels in preeclamptic patients is negligible but the possibility that intravascular platelet activation indirectly contributes “in vivo” to the increase in plasma plasminogen activator inhibitor-1 levels in severe preeclampsia patients cannot be ruled out.

Protein C Inhibitor and Other Components of the Protein C Pathway in Patients with Acute Deep Vein Thrombosis during Heparin Treatment

The protein C inhibitor (PCI) concentration and other parameters of the protein C pathway were studied in 19 patients with symptomatic acute deep vein thrombosis before and during the first 5 days of heparin treatment. The mean levels of PCI antigen and activity decreased rapidly and significantly during the first day of heparin therapy from 83 and 81% to 60 and 59% of the pooled normal human plasma (p <0.01), respectively, and to 56 and 54% after 5 days of treatment (p <0.01). In contrast, antithrom-bin III decreased progressively 25% during 5 days of heparin treatment. Protein C antigen and activity and total protein S remained unchanged during heparin treatment. Free protein S was decreased before heparin treatment (83%, p <0.05) and increased to normal values after 5 days of treatment. C4b-binding protein was significantly increased before and during heparin treatment (p <0.01). Activated protein C (APC) complexed to its two major plasma inhibitors, PCI and α1-antitrypsin (α1AT) were measured by specific ELISA’s. Before treatment, 18 of the 19 patients studied had increased levels of APC: α1AT complexes with a mean value of 27 ± 22 ng/ml (range, 6−86 ng/ml) compared to normal values (8 ± 2 ng/ml) and 12 of the patients also had detectable APC:PCI complex levels with a mean value of 11 ±17 ng/ml (range, 5−68 ng/ml). Both APC:inhibitor complexes decreased significantly during heparin treatment.

Low Level of Circulating Activated Protein C Is a Risk Factor for Venous Thromboembolism

The levels of circulating activated protein C (APC) reflect in vivo protein C activation. The aim of this study was to determine whether a low APC level is an independent risk factor for venous thromboembolism (VTE). We measured APC in 160 patients with a history of VTE and without recognized thrombophilic defects, and in 199 healthy individuals. The mean (±SD) APC level was lower in patients (0.99 ± 0.44 ng/ml) than in controls (1.19 ± 0.41 ng/ml) (p <0.0001), and showed a different distribution in the two groups. Thirty-eight patients (23.7%) had APC levels below the 5th percentile of the control group (<0.69 ng/ml) and 57 patients (35.6%) had APC levels below the 10th percentile (<0.77 ng/ml). APC levels <0.69 ng/ml increased the risk of a single or recurrent episode of VTE 4.2-fold (95% confidence interval, 2.0-9.0) or 6.9-fold (2.6-17.9), respectively, and APC levels <0.77 ng/ml increased these risks 3.4-fold (1.9-6.2) or 5.1-fold (2.3-11.2), respectively, compared with controls. Familial studies revealed that in some cases the low APC phenotype seems to be hereditary. We conclude that a low level of circulating APC in individuals without any of the most recognized thrombophilic defects is a prevalent, independent risk factor for VTE, and that it predisposes to recurrent VTE.

Plasma PAI-1 Levels in Obese Children – Effect of Weight Loss and Influence of PAI-1 Promoter 4G/5G Genotype

An association between an increase in plasminogen activator inhibitor type 1 (PAI-1) and obesity, and also between elevated levels of PAI-1 and the presence of PAI-1 promoter 4G allele has been described in adults and can contribute to increased risk of cardiovascular disease. It has also been suggested that in adults a decrease in adiposity has beneficial effects on the haemostatic system. However, less information is available regarding adiposity and fibrinolysis in children. The aim of the present study is to evaluate the effect of weight loss and the influence of the PAI-1 promoter 4G/5G genotype on the fibrinolytic system and lipid parameters in obese children. The clinical groups included 102 obese children and 105 controls of similar age and sex distribution. A significant decrease in fibrinolytic activity due to a significant increase in PAI-1 antigen and activity levels was observed in the obese children in comparison with the control group. In obese children, no significant differences in PAI-1 levels between the PAI-1 4G/5G genotypes were obtained. A significant correlation was observed between PAI-1 antigenic and functional levels and body mass index (BMI), as well as between PAI-1 levels and both triglyceride and insulin levels. No correlation between PAI-1 levels and either cholesterol or glucose levels was observed.

After a three-month period of treatment to reduce weight, an increase in fibrinolytic activity due to a decrease in PAI-1 levels was observed in the obese children who had reduced their BMI in comparison with the group of obese children who did not show a decrease in their BMI. No significant differences between the two groups with respect to the variations in tissue type plasminogen activator and fibrinogen levels were obtained after three months of intervention to reduce weight. A significant correlation was observed between variations in BMI and variations in PAI-1 levels, and a significant inverse correlation was also observed between previous PAI-1 levels and variation in PAI-1 levels. Therefore, the largest decrease in PAI-1 levels was observed in the obese children with the highest previous PAI-1 levels.

In conclusion, a decrease in BMI in obese children shows a favourable effect on the fibrinolytic system due to a decrease in PAI-1 levels. However, no influence of 4G/5G genotype on PAI-1 levels was observed.

Plasminogen Activator Inhibitor-1 (PAI-1) Promoter 4G/5G Genotype and Increased PAI-1 Circulating Levels in Postmenopausal Women with Coronary Artery Disease

Increased circulating levels of type 1 plasminogen activator inhibitor (PAI-1) have been associated with coronary artery disease (CAD). However, genetic and environmental determinants of PAI-1 expression are only partially understood. The levels of PAI-1 have been found to relate to 4/5 guanosine (4G/5G) polymorphism in the promoter region of the PAI-1 gene. The 4G allele in this polymorphism has been associated with higher levels of plasma PAI-1 activity, but despite the strong correlation between PAI-1 activity and antigen, no association has been found between PAI-1 antigen levels and the PAI-1 promoter 4G/5G genotype. The aim of the present study was to analyze the influence of the PAI-1 promoter 4G/5G genotype on PAI-1 levels in post-menopause women with coronary disease in comparison with healthy women in pre and postmenopausal status, and the influence of this genotype on variations in PAI-1 levels after hormone replacement therapy (HRT). No differences between 4G/5G allele distribution in the groups studied were observed. The group of postmenopausal women with CAD showed significantly increased PAI-1 antigen and activity levels in comparison with the control groups, and the levels of PAI-1 correlated with the 4G/5G genotype. A multivariate analysis revealed that in the CAD group there was a high correlation between 4G allele dosage and PAI-1 antigen levels, which were also influenced by the triglyceride levels but not by estrogen or glucose levels. After hormone replacement therapy the decrease in PAI-1 levels was correlated with the 4G allele dosage. We conclude that in the group of postmenopausal women with CAD the influence of the PAI-1 promoter 4G/5G genotype on PAI-1 levels is more evident than in the control groups, and that the decrease in PAI-1 levels after HRT in CAD women correlates with the 4G allele dosage.

Elevated High Molecular Weight Fibrinogen in Plasma Is Predictive of Coronary Ischemic Events after Acute Myocardial Infarction

This study investigates the association between the concentration and function of plasma fibrinogen molecules measured at the time of hospital admission in patients with acute myocardial infarction (AMI), with reference to the risk of new coronary ischemic events during a three-day follow-up period of. Before starting fibrinolytic and anticoagulant treatment plasma fibrinogen, high molecular weight fibrinogen (HMW-fibrinogen), fibrin formation rate (FbFR) and phosphorous content in fibrinogen were determined in 90 AMI patients. During a three-day follow-up period 12 patients suffered new ischemic events. The 12 patients with coronary ischemia had higher concentrations of plasma fibrinogen (312 ± 23 vs. 270 ± 73 mg/dl, p <0.05) and HMW-fibrinogen (246 ± 35 vs. 189 ± 23 mg/dl, p <0.001) and a higher FbFR (65 ± 30 vs. 40 ± 25, p <0.001) than patients without these events. No association was found between the phosphorous content in fibrinogen and new coronary ischemic events. We conclude that after myocardial infarction an elevated plasma level of HMW-fibrinogen and a high FbFR value at the time of hospital admission are associated with new coronary ischemic events during a three-day follow-up period.

Prothrombin G20210A mutation and oral contraceptive use increase upper-extremity deep vein thrombotic risk

The role played by a hypercoagulable state, either inherited or acquired, in the pathogenesis of upper-extremity deep vein thrombosis (UEDVT) remains a question of debate. We performed a case-control study including 79 patients with a first objectively confirmed episode of UEDVT, 31 secondary and 48 primary, and 165 healthy controls. Nine patients (11.4%) with UEDVT were carriers of the prothrombin G20210A mutation vs. six (3.7%) in controls; P = 0.025, OR: 3.39 (95% CI 1.16 to 9.88). No statistical difference was observed between cases and controls for the factor V Leiden mutation, AT, protein C or protein S deficiency and anticardiolipin antibodies (ACAs). Thirteen (35.1%) UEDVT patients were oral contraceptive (OC) users vs. 12 (16%) controls; P = 0.020, OR: 2.89 (95% CI 1.16-7.21). When secondary UEDVT patients were compared with controls, no differences were observed in any of the risk factors analysed. On the other hand, when primary UEDVT was considered, six (12.5%) patients were carriers of the prothrombin G20210A mutation vs. six (3.7%) controls; P = 0.031, OR: 3.76 (95% CI 1.15-12.26). Regarding ACAs, a borderline statistical significance was observed when primary UEDVT was compared with controls, P = 0.048; OR: 4.88 (95% CI 1.05-22.61). In primary UEDVT, 52% of the fertile women were OC users vs. 16% of controls; P = 0.001, OR:5.78 (95% CI 2.13-15.67). When the interaction of both factors, i.e. prothrombin G20210A mutation and OC intake, were considered, the risk increased markedly, indicating a synergistic effect as observed with other thrombotic locations. In patients with primary UEDVT screening for antithrombin, protein C and protein S deficiency and APC resistance would not be justified, although it might be reasonable to determine the carrier status of the prothrombin G20210A mutation only in OC users.

Hereditary Homozygous Heparin Cofactor II Deficiency and the Risk of Developing Venous Thrombosis

Heparin cofactor II (HCII) is a specific inhibitor of thrombin in the presence of heparin or dermatan sulphate. Although there have been reports on families in which a heterozygous HCII deficiency is associated with thromboembolic events, several epidemiological studies revealed that heterozygous HCII deficiency is as prevalent among healthy subjects as it is among patients with deep venous thrombosis (DVT). It is therefore not yet clear whether HCII is or is not a thrombotic risk factor.

We analyze and describe in an extended family the biochemical and genetic thrombophilic risk factors and evaluate the potential thrombotic risk involved in homozygous and heterozygous HCII deficiency, either alone or associated with other thrombotic or circumstantial risk factors. The propositus has had three episodes of DVT and a pulmonary embolism. During the first episode of DVT the patient was diagnosed as having AT deficiency. Later, a functional and antigenic HCII deficiency, compatible with the homozygous form, was detected. The family study shows that both the propositus and her sister have homozygous HCII deficiency and that 12 of the 27 family members have heterozygous HCII deficiency.

This is possibly the first case report on a homozygous phenotype for the HCII deficiency with, in addition, partial AT deficiency. The propositus has suffered several thrombotic events, unlike the other 12 family members with heterozygous HCII deficiency and her sister, who is also homozygous for this disorder. We suggest that HCII deficiency may play a limited in vivo role as a thrombotic risk factor unless associated with AT deficiency or another congenital thrombotic risk factor.

Lipoprotein(a) Levels and Isoforms and Fibrinolytic Activity in Postmenopause – Influence of Hormone Replacement Therapy

Epidemiological studies suggest that hormone replacement therapy (HRT) decreases the risk of cardiovascular disease in postmenopausal women via several mechanisms, including modifications in the fibrinolytic system and lipoprotein(a) [Lp(a)] levels. The aim of this study was to examine the influence of the levels and isoforms of Lp(a) on fibrinolytic activity in 91 postmenopausal women in comparison with premenopause and analyze the effect of HRT on those parameters. In postmenopause, an increase in plasma Lp(a) and plasminogen activator inhibitor-1 (PAI-1) levels was found. A significant inverse correlation was observed between Lp(a) or PAI-1 levels and plasmin generation. Plasma samples with low molecular weight (MW) apo(a) isoforms showed higher plasmin inhibition than plasmas with high MW apo(a) isoforms and similar levels of total Lp(a) and PAI-1. HRT induced a significant decrease in Lp(a) and PAI-1 levels and an increase in estradiol levels, as well as an increase in fibrinolytic activity. A significant correlation was found between the percentages of variation in Lp(a) levels and in plasmin generation and between the percentages of variation in PAI-1 levels and in the euglobulin lysis time under HRT. In conclusion, the increase in fibrinolytic activity observed in women under HRT could be explained by two independent mechanisms: (a) the decrease in PAI-1 and (b) the decrease in the inhibition of plasmin generation due to the decrease in Lp(a) levels.

Influence of Lipoprotein (a) Levels and Isoforms on Fibrinolytic Activity – Study in Families with High Lipoprotein (a) Levels

Increased levels of lipoprotein (a) [Lp(a)] have been considered an independent risk factor for cardiovascular disease, but the mechanism behind this relationship is not completely understood. A high concentration of Lp(a) may interfere with fibrinolysis because of the structural similarity between apo(a) and plasminogen. The aim of the present study was to examine the influence of apo(a) levels and isoforms on fibrinolytic activity in 82 subjects from 24 families in which the Lp(a) levels were ≥30 mg/dl in at least one child and one parent. Several fibrinolytic parameters, including plasmin generation by fibrin-bound tissue plasminogen activator, the lipid profile and apo(a) isoforms were studied. Subjects with high circulating Lp(a) levels (n = 44) had significantly reduced plasmin generation compared with their relatives with normal Lp(a) levels (n = 38). A significant inverse correlation between Lp(a) levels and plasmin generation was observed. The individuals with a combination of high levels of plasma Lp(a) and a major apo(a) isoform ≤580 kD molecular weight show the lowest fibrinolytic activity. A high correlation was found between the levels of apo(a) isoforms in children and the levels of the corresponding parental apo(a) iso-forms. We conclude that the antifibrinolytic effect of Lp(a) in subjects with two apo(a) isoforms may depend not only on the total plasma level of Lp(a) but also on the relative concentration of the small apo(a) isoform.

Abnormal Expression of Type 1 Plasminogen Activator Inhibitor and Tissue Factor in Severe Preeclampsia

Preeclampsia is a multisystemic obstetric disease of unknown etiology that is commonly associated with fibrin deposition, occlusive lesions in placental vasculature, and intrauterine fetal growth retardation. We previously reported that type 1 plasminogen activator inhibitor (PAI-1) levels are significantly increased in plasma and placenta from pregnant women with preeclampsia compared to normal pregnant women. In the present report we localize the expression of placental PAI-1 in greater detail and compare it with that of tissue factor (TF), a procoagulant molecule, and vitronectin (Vn), a PAI-1 cofactor. We also examine the expression of two cytokines, tumor necrosis factor α (TNFα) and interleukin-1 (IL-1), in order to begin to define the underlying mechanisms responsible for the elevated levels of PAI-1 and fibrin deposits observed in placenta from preeclampsia. We demonstrate a significant increase in PAI-1, TF and TNFα antigen and PAI-1 and TF mRNA in placentas from preeclamptic patients. PAI-1 mRNA was increased not only in syncytiotrophoblast and infarction areas, but also in fibroblasts and in some endothelial cells of fetal vessels in placentas from preeclamptic patients. However, there was no colocalization between PAI-1, TF, Vn and TNFα in placental villi. The elevated TNFα in the placenta may induce PAI-1 and TF, and thus promote the thrombotic alterations associated with preeclampsia.