Human degradation of tropical moist forests is greater than previously estimated.

Tropical forest degradation from selective logging, fire and edge effects is a major driver of carbon and biodiversity loss1-3, with annual rates comparable to those of deforestation4. However, its actual extent and long-term impacts remain uncertain at global tropical scale5. Here we quantify the magnitude and persistence of multiple types of degradation on forest structure by combining satellite remote sensing data on pantropical moist forest cover changes4 with estimates of canopy height and biomass from spaceborne6 light detection and ranging (LiDAR). We estimate that forest height decreases owing to selective logging and fire by 15% and 50%, respectively, with low rates of recovery even after 20 years. Agriculture and road expansion trigger a 20% to 30% reduction in canopy height and biomass at the forest edge, with persistent effects being measurable up to 1.5 km inside the forest. Edge effects encroach on 18% (approximately 206 Mha) of the remaining tropical moist forests, an area more than 200% larger than previously estimated7. Finally, degraded forests with more than 50% canopy loss are significantly more vulnerable to subsequent deforestation. Collectively, our findings call for greater efforts to prevent degradation and protect already degraded forests to meet the conservation pledges made at recent United Nations Climate Change and Biodiversity conferences.

Tropical forests were the primary sources of new agricultural land in the 1980s and 1990s.

Global demand for agricultural products such as food, feed, and fuel is now a major driver of cropland and pasture expansion across much of the developing world. Whether these new agricultural lands replace forests, degraded forests, or grasslands greatly influences the environmental consequences of expansion. Although the general pattern is known, there still is no definitive quantification of these land-cover changes. Here we analyze the rich, pan-tropical database of classified Landsat scenes created by the Food and Agricultural Organization of the United Nations to examine pathways of agricultural expansion across the major tropical forest regions in the 1980s and 1990s and use this information to highlight the future land conversions that probably will be needed to meet mounting demand for agricultural products. Across the tropics, we find that between 1980 and 2000 more than 55% of new agricultural land came at the expense of intact forests, and another 28% came from disturbed forests. This study underscores the potential consequences of unabated agricultural expansion for forest conservation and carbon emissions.

Long-term (1990-2019) monitoring of forest cover changes in the humid tropics.

Accurate characterization of tropical moist forest changes is needed to support conservation policies and to quantify their contribution to global carbon fluxes more effectively. We document, at pantropical scale, the extent and changes (degradation, deforestation, and recovery) of these forests over the past three decades. We estimate that 17% of tropical moist forests have disappeared since 1990 with a remaining area of 1071 million hectares in 2019, from which 10% are degraded. Our study underlines the importance of the degradation process in these ecosystems, in particular, as a precursor of deforestation, and in the recent increase in tropical moist forest disturbances (natural and anthropogenic degradation or deforestation). Without a reduction of the present disturbance rates, undisturbed forests will disappear entirely in large tropical humid regions by 2050. Our study suggests that reinforcing actions are needed to prevent the initial degradation that leads to forest clearance in 45% of the cases.

Interconversions and distinct metabolic fate of eicosapentaenoic, docosapentaenoic and docosahexaenoic acids in bovine aortic endothelial cells.

The anti-aggregatory activity of endothelial cells being affected by eicosapentaenoic (EPA, 20:5(n-3)) and docosahexaenoic (DHA, 22:6(n-3)) acids, the two main polyunsaturated fatty acids of fish oil, these fatty acids, as well as their intermediary, docosapentaenoic acid (DPA, 22:5(n-3)), were investigated with respect to their metabolism. Primary cultured bovine aortic endothelial cells were supplemented for 22 h at 37 degrees C with either n-3 fatty acid, and the fatty acids of cell media, of cell lipid classes, and of choline and ethanolamine glycerophospholipids (PC and PE) were quantified. Endothelial cells converted each of the three fatty acids into the two others. They were found esterified in cell lipids and partly released in cell media, the respective parts varying according to the fatty acid. For instance, half of the DPA formed from EPA and two third of the EPA formed from DPA were released in the media. Moreover, the DHA formed from EPA and DPA was not esterified but released in media. In addition, the esterified counterparts were found in either PC or PE, depending on whether they were added or formed by conversions. It is concluded that EPA, DPA and DHA are actively interconverted each others, and differ substantially in terms of distribution between media and cells, and within phospholipid classes.

XML: a lingua franca for science?

XML is a new language designed to solve one of the biggest problems of the World Wide Web: its main language, HTML, is not extensible. In this article, the authors discuss the current successes and limitations of the World Wide Web, briefly explain the basics of XML and present the benefits of using XML as a data-exchange language. Finally, they discuss real-life applications that have been developed using XML, with a focus on biology.

Platelet inhibitory functions of aortic endothelial cells. Effects of eicosapentaenoic and docosahexaenoic acids.

The endothelial cell platelet inhibitory potential was assessed directly by measuring the platelet inhibition induced by platelet interaction with the cultured aortic endothelial cell. The prostacyclin content of the platelet suspensions after interaction was also quantified. We found that prostacyclin production accounted for the overall platelet inhibitory potential of the aortic cells since: (a) endothelial cells incubated with aspirin, which did not produce prostacyclin, did not inhibit platelets; (b) the prostacyclin content of platelet suspensions after interaction with endothelial cells correlated with the extent of the platelet inhibition; (c) such a platelet inhibition was reproduced by adding synthetic prostacyclin in amount equivalent to that produced by endothelial cells during the interaction. Eicosapentaenoic (EPA) and docosahexaenoic (DHA) acids incorporated into endothelial phospholipids, decreased the ability of the cells to produce prostacyclin and to inhibit platelets, DHA being less effective than EPA.

Docosapentaenoic acid (22:5,n-3): metabolism and effect on prostacyclin production in endothelial cells.

Eicosapentaenoic acid (EPA, 20:5,n-3) and docosahexaenoic acid (DHA, 22:6, n-3), the two main fatty acids of fish oil, have been shown to inhibit prostacyclin production and to be actively interconverted, leading to the accumulation of docosapentaenoic acid (DPA, 22:5,n-3) in endothelial cell phospholipids. We have investigated the effect of supplementing endothelial cells with DPA on their capacity to produce prostacyclin. We found that endothelial cells incubated for 22 h with 25 microM DPA bound to albumin (fatty acid/albumin ratio of 1.3) produced two-fold less prostacyclin compared to control cells when stimulated with endogenous arachidonic acid-mobilizing agents such as bradykinin and calcium ionophore A23187. Since the formation of prostacyclin from 0.1-15 microM exogenous arachidonic acid was also reduced, it is suggested that prostacyclin inhibition observed in DPA-treated cells might not proceed from a reduction of arachidonic acid availability only. Such an inhibition was already observed after 1 h incubation of the cells with DPA, and with 2-20 times lower DPA concentrations. The inhibition might depend on EPA which was formed by retroconversion of DPA.

Relationships between electromyographic ileal and colonic motility patterns in cats during fasting and feeding.

The relationship between ileal and colonic electromyographic motility patterns were investigated in six awake cats chronically fitted with subserosal electrodes implanted in the smooth muscles of the ileum and colon. Smooth muscle electrical activity (electromyogram) was recorded in both fed and fasted conditions under a 12-12 hours dark-light schedule. It consisted of electrical long spike bursts having two different patterns for each condition. Short sequences of three to five long spike bursts were propagated either aborally or orally from any part of the colon; they were most frequent during the interdigestive or fasting period and no relationship was observed between these long spike bursts and the electrical activity of the ileum. During the digestive or feeding period, the colonic activity was organized in long sequences of 10-15 long spike bursts, termed migrating spike bursts, which started near the caecal junction and propagated aborally to the distal colon. These migrating spike bursts were correlated with the ileal motility. This relationship demonstrated between ileum and colon after feeding is dependent upon the amount of food intake.

[Study of the mechanism of an atrial pause using endocavitary recording of the sinus node potential in man]. / Etude du mécanisme de la pause auriculaire par l'enregistrement endocavitaire du potentiel sinusal chez l'homme.

The aim of this clinical study was to determine the electrophysiological mechanism of spontaneous atrial standstill, defined as a sudden lengthening of the trial cycle to over 10 p. 100 of its basal value, by recording the sinus node potential by endocavitary electrocardiological techniques. Satisfactory recordings of the sinus potential were obtained for the study of 65 atrial pauses recorded in 31 patients (18 without sinus node dysfunction and 13 with sinus node disease). It was shown that atrial pauses, shorter than two basal atrial cycles correspond to a moderate slowing of the sinus rhythm and to a sometimes very significant lengthening of the sinoatrial conduction time when sinus rhythm resumed. Pauses longer than two basal atrial cycles were always due to sinoatrial block which sometimes occured in patients with clearly individualised sinus activity, and sometimes with a slow continuous sinus activity. The sinus period did not change during these long pauses and sinoatrial conduction was normal when sinus rhythm resumed. The increased duration of the sinus potential, a constant finding during these pauses, is related to an intrasinusal conduction defect. This suggest that the primum movens of sinoatrial block is intrasinusal block which prevents rapid recruitment of a sufficient number of elemental sinus potentials so that the resultant potential becomes subliminal and therefore incapable of passing the sinoatrial junction. Short-lasting atrial pauses with a normal response to extrastimulus or atrial stimulation and characterised electrophysiologically by an increased sinoatrial conduction time without block of the sinus potential may be opposed to long atrial pauses with the pathological response of sinus node dysfunction characterised electrophysiologically by block of the sinus impulse. In practice the ability to induce a long pause by atrial stimulation (sinoatrial block) revealing latent disease of intrasinusal or sinoatrial conduction, may constitute an essential physiological sign of sinus node dysfunction.

[Identification of the sinus potential in man by endocavitary electrocardiography. Identification criteria, preliminary results]. / Identification du potentiel sinusal par électrocardiographie endocavitaire chez l'homme. Critères d'identification, résultats préliminaires.

The potential of the sinus node was recorded in 24 patients by endocavitary electrocardiography using the same equipment as for usual electrophysiological investigation. The sinus node potential is a slow wave which starts progressively, has a rounded peak and precedes the endocavitary atrial activation and the surface P wave, and is relayed at an acute angle to the high amplitude deflection of atrial depolarisation. In some specially selected recordings it is easy to confirm the sinus origin of this slow wave where its preatrial position may be defined by the fixed relation of the S-P interval and by the variability of the T-S interval. Usually it is necessary to use technical manoeuvres (vagal stimulation, premature atrial stimulation) to demonstrate the preatrial behaviour of a potential thought to be of sinus origin. The variability of the sinus potential and the apparent sinoatrial conduction time, is suggestive of a physiological instability of the intrasinus pacemaker. The sinoatrial conduction time measured directly does not seem to exceed 140 ms in normal subjects.

[Enoximone: hemodynamic effect in patients with cardiac insufficiency]. / Enoximone: effet hémodynamique chez l'insuffisant cardiaque.

Enoximone, a phosphodiesterase inhibitor, is a positive inotropic agent with direct vasodilator properties. Its acute effects after I.V. administration and the possibility of oral relay were studied in 14 patients (13 men and 1 woman), 40 to 78 years of age (mean 61 years) with Stage IV cardiac failure (NYHA Classification). Eleven patients had dilated cardiomyopathy, 2 had ischemic heart disease and 1 a dilated hypertrophic cardiomyopathy. The haemodynamic inclusion criteria were: cardiac index less than or equal to 2.2 l/mn/m2 and pulmonary capillary pressure greater than or equal to 18 mmHg. Patients with cardiogenic shock and severe renal or hepatic failure were excluded. The drug was administered as a bolus of 1 mg/kg followed by a continuous infusion of 5 to 15 g/kg/mn (average 8.9 +/- 2.6 for 7 to 72 hours; average 27 +/- 16 hours). Haemodynamic effects of I.V. administration: no change in heart rate, slight lowering of blood pressure, very significant reduction in right atrial and pulmonary capillary pressures, of pulmonary artery pressures, of arteriolo-capillary and systemic resistances and marked increase in cardiac output. General tolerance was excellent with no clinical secondary effects and no signs of hepatic, renal or haematological (platelets) toxicity. Cardiac tolerance was also excellent, no aggravation of preexisting arrhythmias. There was no immediate mortality. Oral relay was undertaken in 14 patients with a daily dose of 300 mg in 12 cases, 400 mg in 1 case and 500 mg in 1 case. Six patients underwent control haemodynamic evaluation on the 8th day: there were no signs of the haemodynamic improvement obtained by I.V. administration.(ABSTRACT TRUNCATED AT 250 WORDS)

[Coronary angioplasty in the treatment of threatening extension of myocardial infarction]. / Apport de l'angioplastie coronaire dans le traitement de la menace d'extension d'infarctus.

Recurrent angina with reversible ECG changes within days of a myocardial infarction is a serious clinical entity associated with a high incidence of reinfarction and death. In this study, we report a one-year experience of the treatment and outcome of patients presenting early post-myocardial infarction angina. Out of 32 patients who underwent coronary angiography, 3 were treated medically, 4 were operated upon and 25 had coronary angioplasty at the same time as coronary angiography with a 100 p. 100 immediate success rate. Four early reocclusions were redilated successfully. While in hospital 3 of these 32 patients had myocardial infarct extension (very moderate in 2 cases with CPK less than 500 and a patent artery), and there was no death. During an 8-month follow-up period there were 3 late deaths and 2 reinfarctions; 4 patients were operated upon and 4 were redilated. Thus, angioplasty has a high success rate in early post-myocardial infarction angina, enabling most patients to get through an unstable phase. In some patients, however, the course of the disease is marred by secondary adverse events.

[Pulmonary embolism and preventive anticoagulant treatment in hospitalized elderly patients. Statistical study of their respective risks]. / Embolies pulmonaires et traitement anticoagulant préventif chez les malades âgés hospitalisés. Etude statistique de leurs risques respectifs

Pulmonary embolism and preventive anticoagulant therapy of ederly patients in hospital. Statistical survey of their respective risks. The incidence of pulmonary embolism as a cause of death seems the higher as its strikes old people (above 60) affected by cardiovascular diseases and who are bed tied; the interest of preventive anticoagulant treatment (PAT) remains controversial. This matter has been studied over a period of 5 years from the files of a geriatric cardiology department; 455 anatomo-clinical documents have been set up. This survey confirms the frequency of mortality by pulmonary embolism (23,9 %) and its diminution under long-term preventive anticoagulant treatment 6,6 %). The anticoagulant therapy does not increase the risk of haemorrhagic accidents, from the point of view of frequency, but slightly increases it if one considers the number of days spent in hospital. As a conclusion, the preventive anticoagulant treatment seems positive insofar as contra-indications are strictly observed, in particular the digestive ones. The mechanism of some hemorrhagic accidents with or without PAT remains sometimes difficult to explain.

[Electromyographic profile of the human jejunum after abdominal surgery]. / Profil électromyographique du jéjunum humain après chirurgie abdominale.

The purpose of this work was to describe the electromyographical profile of the jejunum observed after various types of abdominal operations. The electromyogram of the first 140 centimeters of the small intestine was recorded on a continuous basis by an intraluminal tube between the 6th and 20th day after abdominal surgery in twenty patients. Results allow us to describe a profile of the patient's intestinal electromyogram after abdominal surgery. It was characterized by three consecutive periods: a) early reappearance of migrating myoelectric complexes occurring during the first period; b) a very short second period beginning immediately before the expulsion of gases; during this period the electrical activity fluctuated and appeared disorganised; c) finally, during the third period, after gas expulsion, peristaltic rushes were associated with normalized migrating myoelectrical complexes. Both early and permanent migrating myoelectrical complexes characterize the normal postoperative period. Continuous linear integration of the jejunal electromyogram might be a useful tool for the monitoring of postoperative intestinal motility as a routine procedure.

[Impact of therapeutics on sex. Value of measurements of quality of life]. / Impact des thérapeutiques sur la sphère sexuelle. Intérêt des mesures de la qualité de vie.

Quality of Life is a new clinical dimension with the objective of evaluating the impact of a disease or of a treatment on patients well being. Quality of life is a measure of increasing interest. It is a global and cumulative measure, relevant for the evaluation of the therapeutic benefit of a treatment. It can be measured through "specific" or "generic" tools. Very few experimental literature exploring the impact of pathologies over the sexual sphere exists today. Only generic scales have been used, because no specific scale has been developed up to now. The impact of certain pathologies such as depression or diabetes has been documented, but very little objective information exists concerning the sexual repercussion of the chronic use of drugs (anti depressive, anxiolytics). Sexual quality or life as a risk factor for disease development is also dimension that has been explored, but only superficially. In a general way, no evidence exists concerning a reel correlation link between pathologies, treatments and sexual quality of life and this specific dimension of the quality of life still remains to be explored further.

Virgil: a database of rich links between GDB and GenBank.

Database interconnection requires the development of links between related objects from different databases. We built a database of links, called Virgil, to manage and distribute rich (documented) links between GDB genes and GenBank human sequences. Virgil contains 18 667 unique links. In addition to a simple Web form for ad-hoc queries, we propose a generic Web interface and a prototype CORBA server for link distribution. Materials described in this paper are available from http://www.infobiogen.fr/services/virgil/home. html

GenXref. VI: Automatic generation of links between two heterogeneous databases.

MOTIVATION: A large proportion of the information found in public databases is not sufficiently cross-referenced. We developed genXref, an automated system for link inference, because embarking on a manual cross-referencing of genome data would require too much expensive human expertise. It uses information retrieval technology to generate links between objects of heterogeneous databases. RESULTS: GenXref was used to generate links between GDB genes and Genbank human sequences. It resulted in > 10,000 links with a precision of 83% and a recall of approximately 32%.

Ubiquitous distributed objects with CORBA.

Database interoperation is becoming a bottleneck for the research community in biology. In this paper, we first discuss the question of interoperability and give a brief overview of CORBA. Then, an example is explained in some detail: a simple but realistic data bank of STSs is implemented. The Object Request Broker is the media for communication between an object server (the data bank) and a client (possibly a genome center). Since CORBA enables easy development of networked applications, we meant this paper to provide an incentive for the bioinformatics community to develop distributed objects.

XML, bioinformatics and data integration.

MOTIVATION: The eXtensible Markup Language (XML) is an emerging standard for structuring documents, notably for the World Wide Web. In this paper, the authors present XML and examine its use as a data language for bioinformatics. In particular, XML is compared to other languages, and some of the potential uses of XML in bioinformatics applications are presented. The authors propose to adopt XML for data interchange between databases and other sources of data. Finally the discussion is illustrated by a test case of a pedigree data model in XML. CONTACT: Emmanuel.Barillot@infobiogen.fr