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The geographical distribution of species differentiation throughout the natural range of two sympatric, closely related species of oaks, Quercus petraea (Matt) Liebl. and Quercus robur L., was investigated.By sampling species in pairs in different European regions, from Spain to Poland and Romania, the differentiation between the two speciescould be subdivided into general and local differentiation. Nine sequence characterized amplified region (SCAR) markers corresponding to genomic regions which discriminate the two species were analysed using single-strand conformation polymorphism (SSCP) or classical electrophoresis (double-stranded DNA on agarose gel) on PCR products providing, respectively, codominant and dominant markers. Similar levels of gene diversity (HE) within the two species were observed, varying generally from 0.3 to 0.5 for dominant markers and from 0..5 to 0.86 forcodominant markers. SSCP loci exhibited numerous alleles that were differently involved in species differentiation. The geographical distribution of species differentiation is heterogeneous between the regions, the north-east populations exhibiting higher differentiation than the others. For most loci, general differentiation was higher than local differentiation and was interpreted as the result of historicalcauses, selection pressures, and intra- and interspecific gene flow. [ABSTRACT FROM AUTHOR]

Information Extraction (IE) is a core task in Natural Language Processing (NLP) where the objective is to identify factual knowledge in textual documents (often unstructured), and feed downstream use cases with the resulting output. In genomic medicine for instance, being able to extract the most precise list of phenotypes associated to a patient allows to improve genetic disease diagnostic, which represents a vital step in the modern deep phenotyping approach. As most of the phenotypic information lies in clinical reports, the challenge is to build an IE pipeline to automatically recognize phenotype concepts from free-text notes. A new machine learning paradigm around large language models (LLM) has given rise of an increasing number of academic works on this topic lately, where sophisticated combinations of different technics have been employed to improve the phenotypes extraction accuracy. Even more recently released, the ChatGPT 1 application nevertheless raises the question of the relevance of these approches compared to this new generic one based on an instruction-oriented LLM. In this paper, we propose a rigorous evaluation of ChatGPT and the current state-of-the-art solutions on this specific task, and discuss the possible impacts and the technical evolutions to consider in the medical domain.Clinical relevance- Deep phenotyping on electronic health records has proven its ability to improve genetic diagnosis by clinical exomes [10]. Thus, comparing state-of-the-art solutions in order to derive insights and improving research paths is essential.

Introduction: Multiple sclerosis (MS), a neuroinflammatory and demyelinating disease, modifies the normal connectivity among different brain regions involved in specific functions. Functional magnetic resonance imaging (fMRI), based on local changes in oxygen level as a response to the increase in neural activity, provides an approach to neural connectivity and brain dynamics which give us an overview on visual, motor and cognitive dysfunction and their mechanisms., Development: An advanced search was performed using PubMed. Terms 'fMRI', 'visual', 'motor', 'cognitive' and 'multiple sclerosis' included in title and abstract were considered. We focus on original articles available in English. Articles were included based on their abstracts, looking for those potentially useful for understanding functional changes in MS. An important amount of studies have used fMRI as a complementary tool in the study of MS and clinically relevant alterations compromising visual, motor and cognitive domains. Since the earliest stages of the disease, local activity, and global neural dynamics appear to be compromised. Even when functional performance is still preserved, a different recruitment of neural resources arises as a compensatory response to disconnection observed in the disease., Conclusions: The main findings of fMRI applied to MS are strongly related to the demyelinating nature of the disease and provide an adequate insight into the mechanisms that underlie functional alterations reported in this disease. fMRI also appears to be useful for studying disease evolution and response to treatment in MS and other disorders.

The presence of "strands" on mitral mechanical prostheses (MMP) has been described, although their significance has yet to be established. The aim of this study was to determine the incidence and clinical implications of "strands" on MMP in late follow-up by a retrospective analysis of 320 consecutive patients who had undergone a transesophageal echocardiographic (TEE) examination under standardized conditions 7 +/- 6 years after mitral surgery. Twenty patients (6.25%) with "strands," defined as highly mobile linear echogenic densities, were identified. This group was compared with a control group of 38 patients, matched for age, sex, and interval between surgery and TEE study, selected at random from this population. Patients with MMP dysfunction were excluded. Type of prosthesis, echographic characteristics (left atrial diameter, spontaneous echo contrast, ejection fraction), and anticoagulant status were not found to bear any relationship to the presence of strands. However, the prevalence of previous embolic events was significantly higher in the "strand" group (10/20 [50%]) than in the control group (7/38 [18.4%]) (P < 0.05). The "strand" group also contained more patients with a prior history of mitral prosthesis thrombosis (7/20 [35%] vs 1/30 [2.6%]; P < 0.05). However, long-term follow-up (1-4 years) was uneventful. These results suggest that: (1) in late follow-up, strands are rare in patients with MMP (6%); and (2) strands were related to previous thromboembolic episodes. (ECHOCARDIOGRAPHY, Volume 13, May 1996)

Coronary angioplasty is sometimes thought to be insufficiently validated considering the considerable development it has undergone and its place in modern cardiological practice. Nevertheless, several randomised clinical trials comparing angioplasty with medical therapy in stable angina (ACME) and with surgical treatment in stable and unstable angina (RITA) have provided more scientific support for the technique. The serious perioperative complications have become rare, the limiting factor being restenosis which is responsible for a large number of clinical recurrences and the reappearance of documented myocardial ischaemia. It is therefore logical to make restenosis the first objective of evaluation of PTCA. There are two possible approaches to this problem. The first relies on automatic quantitative operator-independent angiography as a gold standard. However, this method is methodologically complex, technically fastidious and only takes into consideration the anatomical appearances, the correlations with clinical outcome and prognosis of which are poor. It allows measurement of the amplitude of the process which is an unquestionable advantage, but it is only a partial view of the problem. The second method considers that only stenosis causing ischaemia is significant and that the criterion of evaluation should be the rate of new events and that the necessity of repeated attempts at revascularisation is the criterion of failure of the method. This overlooks the possibility of an anti-restenosis drug producing clinical results independents of its anatomical effect. Both methods have their advantages and drawbacks, which necessitates using them both in all trials of new tools or new molecules designed to prevent restenosis.

Forty-three consecutive patients with mechanical valve prostheses underwent transthoracic and transoesophageal echocardiography for suspected thrombolic prosthetic valve dysfunction. The results of these investigations were compared with those of cineradiography and the clinical outcome. The diagnosis of thrombosis was retained in 11 of the 43 patients (10 mitral and 1 aortic valve prostheses). The transthoracic Doppler echo was clearly abnormal in 6 of the 11 cases. Transoesophageal echo was of essential value in all cases but one, showing abnormal movement of the mobile element and/or a paraprosthetic thrombus. The cineradiography gave false negative results in 6 cases. In conclusion, these cases underline the undeniable value of transoesophageal echocardiography in occlusive or non-occlusive thrombosis of a mitral valve prosthesis. This investigation should be undertaken whenever there is the least suspicion of thrombosis of the prosthesis.

The authors report a case of dysfunction of a double hemi-disc mitral valve prosthesis due to peri-annular fibrous overgrowth on the atrial side of the prosthesis. Conventional transthoracic Doppler echocardiography showed signs of thrombosis of the prosthesis. Transoesophageal echocardiography allowed a precise diagnosis of the lesions, resulting in immediate surgical referral.

False-positive responses to exercise tests have been reported as been more frequent in athletes than in the general population and attributed to physiological hypertrophy of the athlete's heart. In this study, we have investigated the significance of major ST depression (-3.55 +/- 1.8 mm) in a group of 13 athletes aged 40 +/- 9 years who had normal coronary angiography. All subjects underwent a standard exercise test followed by a second one after administration of nitroglycerin; the post-test probability of coronary was evaluated by multivariate analysis of the results. Myocardial perfusion was studied in 9 subjects by stress thallium 201 scintigraphy, and the data obtained were compared with those of angiography. Left ventricular hypertrophy was systematically looked for by calculating the myocardial mass index at echocardiography. The subjects were also investigated for possible alteration of the diastolic function, using doppler ultrasound. The mean follow-up period was 5 +/- 2 years. The mean performance at exercise tests was 238 +/- 118 watts. The Q wave significantly increased at exercise (-0.61 +/- 0.8; p less than 0.05), whereas the R wave remained constant (-0.95 +/- 4.5 mm; N.S.). The mean probability or coronary disease was 0.49 +/- 0.41, which justified the thallium scintigraphy test. This test was abnormal in 8 out of 9 cases. The myocardial mass index was slightly increased up to 138 +/- 25 g/m2, reflecting a very moderate physiological hypertrophy, as testified by the normality of diastolic function related to age in 8/9 cases. There was no obvious correlation between ST depression amplitude and myocardial mass index.(ABSTRACT TRUNCATED AT 250 WORDS)