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1.
Plant Biol (Stuttg) ; 26(1): 28-33, 2024 Jan.
Article de Anglais | MEDLINE | ID: mdl-37862291

RÉSUMÉ

Floral scent is a key olfactory cue in both diurnal and nocturnal pollination systems. In the case of nocturnal systems, such as bat-pollinated flowers, odour seems to play a more important role than visual cues. Cactaceae include many bat-pollinated species; however, few studies have investigated the olfactory cues in this family. We analysed and compared the chemical composition of the floral bouquet of three chiropterophilous cactus species, among which are a pair of congeners that differ considerably in scent intensity. Our research presents novel findings regarding the floral scent chemistry of chiropterophilous cactus species. We documented the first case of a bat-pollinated cactus whose flowers lack perceptible floral scent and in which no volatile compounds were detected in our chemical analyses. Additionally, we provide a comprehensive analysis of the chemical composition of the floral bouquet of the other two bat-pollinated species, revealing a resemblance among closely related species within the same genus. We highlight the need for further studies using biotests to investigate the mechanisms through which bats find flowers lacking scent.


Sujet(s)
Cactaceae , Chiroptera , Parfum , Pollinisation , Animaux , Fleurs/composition chimique , Odorisants/analyse , Parfum/analyse , Phéromones
2.
Talanta ; 175: 566-572, 2017 Dec 01.
Article de Anglais | MEDLINE | ID: mdl-28842034

RÉSUMÉ

Main purpose of the work is assembling, testing and optimizing new disposable amperometric biosensors to analyze substances in different application fields as agribusiness, clinical chemistry and environment protection. Many kinds of modified electrodes have been prepared and tested to build portable devices to analyze quickly many analytes, in a simple and cost-effective manner. Bare electrodes of the screen-printed type, with silver as reference, have been used for modification. The glassy carbon electrodes with multi-walled carbon nanotubes or graphene or gold nanoparticles depositions were modified with generation IV ionic liquids. Choline as cation and amino acids, such as glycine, serine, phenylalanine and histidine, as anions have been employed for these ionic liquids. The presence of nanostructured materials on the electrode brings an increased contact surface between analytes and receptor and, consequently, an amplification of the amperometric signal and a better sensibility. Moreover the use of new ionic liquids of generation IV, biologically friendly and water soluble, improves the electronic transfer, facilitating and strengthening the redox reaction nearby the electrode. By immobilizing the proper enzymes onto the modified electrode surface, different compounds of analytical interest can be determined by means of sensitive, properly designed amperometric biosensors. Analytes such as antioxidant components in extra-virgin olive oils, alcohols in beverages and glucose in food matrices have been tested, using a suitable enzyme: microbial lipase, alcohol dehydrogenase and glucose oxidase, respectively.


Sujet(s)
Techniques de biocapteur/instrumentation , Enzymes immobilisées/composition chimique , Liquides ioniques/composition chimique , Nanostructures/composition chimique , Alcohol dehydrogenase/composition chimique , Animaux , Aspergillus niger/enzymologie , Candida/enzymologie , Électrodes , Éthanol/analyse , Glucose/analyse , Glucose oxidase/composition chimique , Or/composition chimique , Triacylglycerol lipase/composition chimique , Nanoparticules métalliques/composition chimique , Nanoparticules métalliques/ultrastructure , Modèles moléculaires , Nanostructures/ultrastructure , Nanotubes de carbone/composition chimique , Nanotubes de carbone/ultrastructure , Huile d'olive/analyse , Suidae , Température
3.
Genet Mol Res ; 12(4): 4579-85, 2013 Feb 28.
Article de Anglais | MEDLINE | ID: mdl-23479172

RÉSUMÉ

Although plastid DNA has been widely explored as a marker of choice for phylogeny and phylogeography studies, little is known about its utility for examining relationships between closely related species. The slow evolutionary rates inherent to chloroplast (cp) DNA make it difficult to perform lower level taxonomic analyses, particularly at the population level. We characterized the nucleotide variation and investigated the utility of eight noncoding cpDNA regions in four closely related species of the Pilosocereus aurisetus group (Cactaceae), an endemic taxon of eastern South America. The plastid intergenic spacers 5'-trnS-trnG, 3'-trnS-trnG and trnT-trnL were the most variable regions and were the most useful for lower level taxonomic comparisons, especially when used together. We conclude that an adequate combination of regions alongside indels as an additional character improves the usefulness of cpDNA for phylogenetic studies.


Sujet(s)
Cactaceae/génétique , ADN des chloroplastes/génétique , Cactaceae/classification , Gènes de plante , Marqueurs génétiques , Phylogenèse , Phylogéographie , Racines de plante/génétique , Polymorphisme génétique
4.
Br J Neurosurg ; 14(2): 110-6, 2000 Apr.
Article de Anglais | MEDLINE | ID: mdl-10889882

RÉSUMÉ

The relationship between radiological findings and outcome in patients with acute posttraumatic subdural haematomas (SDH) has been based on CT obtained upon hospital admission. This study was undertaken to investigate the effects on prognosis of SDH patients of lesions not present on admission, but detected by subsequent CT. We have also studied those findings present on admission CT that could predict worsening of the associated lesions. From 1 May 1989 to 30 April 1996, we admitted 206 patients harbouring acute SDH of thickness 5 mm or more. The admission GCS score ranged from 3 to 15. Each patient underwent CT on admission (always within 3 h from injury). Follow-up CT was performed within 12-24 h after injury and in the following days (an average of 4.3 examinations for each patient). These examinations were reviewed by a neuroradiologist and the 'worst' CT was determined. We defined the 'worst' examination as that showing the largest haematoma thickness/midline shift and/or with the most extensive degree of parenchymal damage. Clinical factors related to prognosis in this series are age, hypoxia/hypotension, GCS motor score and pupillary abnormalities. Time from injury to treatment was found relevant only in patients with isolated SDH. CT findings on admission that correlated with outcome were haematoma thickness, midline shift and status of the basal cisterns. Prognosis was also worsened by the presence of associated lesions; SAH alone or associated with brain contusions. The last of these was the single most powerful predictor of worse outcomes (Odds ratio 0.37, p < 0.004). Whereas the first CT showed parenchymal associated damage in 56 patients, the 'worst CT' showed such damage in 105 patients. Presence of SAH on admission was found significant (p < 0.02) in predicting evolving parenchymal damage. Haematoma thickness, midline shift, status of the basal cisterns and presence of SAH are related to outcome when identified on the initial (early) CT examination. However, early (within 3 h from injury) CT under-estimates the ultimate size of parenchymal contusions. Patients with SAH on early CT are those at highest risk for associated evolving contusions. The use of sequential CT should be included in the routine management of head-injured patients.


Sujet(s)
Encéphale/imagerie diagnostique , Hématome subdural aigu/imagerie diagnostique , Tomodensitométrie , Adolescent , Adulte , Facteurs âges , Sujet âgé , Enfant , Enfant d'âge préscolaire , Femelle , Échelle de coma de Glasgow , Hématome subdural aigu/complications , Humains , Nourrisson , Nouveau-né , Mâle , Adulte d'âge moyen , Pronostic , Troubles pupillaires/diagnostic , Troubles pupillaires/étiologie , Résultat thérapeutique
5.
Arq Bras Cardiol ; 71(4): 609-11, 1998 Oct.
Article de Portugais | MEDLINE | ID: mdl-10347938

RÉSUMÉ

Although Wegener's granulomatosis is known for almost 65 years, the disease is still a dilemma for physicians. This is probably due to its different clinical presentations or to the lack of diagnostic methods. The laboratorial diagnosis is supported on the presence of antineutrophil cytoplasmic antibodies (ANCA-c) and on histological analysis of tissues from affected organs. This paper describes a case report of a patient whose clinical history presented all protean aspects of the disease, including cardiac involvement such as myocarditis, pericarditis and, surprisingly, intracardiac mass.


Sujet(s)
Cardiomyopathies/imagerie diagnostique , Granulomatose avec polyangéite/diagnostic , Adulte , Anticorps anti-cytoplasme des polynucléaires neutrophiles/analyse , Issue fatale , Humains , Mâle , Échographie
6.
Neurosurgery ; 37(5): 899-906; discussion 906-7, 1995 Nov.
Article de Anglais | MEDLINE | ID: mdl-8559338

RÉSUMÉ

From January 1, 1990, to April 30, 1994, 412 patients were admitted to our intensive care unit in coma after head injuries. Our study group consisted of 37 patients who were retrospectively identified as harboring lesions or developing new lesions within a 12-hour period from the time of admission. We defined the evolution of a lesion as an increase or decrease in the size of an already present hematoma or as the appearance of a totally new lesion. There were 25 male and 12 female patients (mean age, 34.9 yr), and the cause of trauma was road traffic accidents in 32 patients. Nine patients presented with shock, and six had evidence of abnormal coagulation at admission. Patients were divided into two different groups. In Group 1, 15 patients harbored lesions that evolved toward reabsorption. In Group 2, 22 patients harbored hematomas that evolved toward lesions requiring surgical removal. Fifteen of these patients had initial diagnoses of diffuse injury that evolved in this manner, whereas the remaining seven patients had already been operated upon and had developed second, noncontiguous, surgical lesions. Patients with lesions that required surgical evacuation had their computed tomographic (CT) scans obtained earlier and had a higher incidence of clinical deterioration. There was a significant difference in the evolution of the different lesions (P < 0.001), with subdural hematomas being more prone to reabsorption and intracerebral and extradural hematomas being more likely to increase in size or to appear as new lesions. Second CT scans were obtained because of clinical deterioration in 10 patients and because of increase in intracranial pressure in 5 patients. Scheduled CT scans were obtained in 13 patients, whereas in the remaining 9 patients, the diagnosis emerged from a combination of scheduled CT scans and intracranial pressure monitoring. There was a trend toward a poorer result among the patients with clinical deterioration, which, however, was not significant. A significant proportion of post-traumatic patients, particularly those who are unconscious, harbor early evolving intracranial lesions. When the first CT scan is performed within 3 hours after injury, a CT scan should be repeated within 12 hours.


Sujet(s)
Hémorragie cérébrale/imagerie diagnostique , Coma/imagerie diagnostique , Traumatismes crâniens fermés/imagerie diagnostique , Tomodensitométrie , Adolescent , Adulte , Sujet âgé , Hémorragie cérébrale/chirurgie , Enfant , Coma/chirurgie , Femelle , Échelle de coma de Glasgow , Traumatismes crâniens fermés/chirurgie , Hématome épidural intracrânien/imagerie diagnostique , Hématome épidural intracrânien/chirurgie , Hématome subdural/imagerie diagnostique , Hématome subdural/chirurgie , Humains , Mâle , Adulte d'âge moyen , Complications postopératoires/imagerie diagnostique , Études rétrospectives
7.
J Neurosurg Sci ; 39(3): 187-90, 1995 Sep.
Article de Anglais | MEDLINE | ID: mdl-8965128

RÉSUMÉ

The case of a 73 year old lady hit by a truck is presented. The patient after a short lucid interval (2 hours) became deeply comatose. CT scan (performed in the clinical phase of minor head injury) showed a posterior fossa subdural haematoma (PFSH) extending towards the cerebello-pontine angle and the brainstem. Prompt evacuation of the haematoma led to recovery with severe disability. Mechanisms and causes of acute PFSH are discussed. As in other published cases the clinical diagnosis of a PSFH is difficult; mortality and morbidity are extremely high in spite of surgical treatment.


Sujet(s)
Lésions encéphaliques/anatomopathologie , Hématome subdural/anatomopathologie , Plaies et blessures/anatomopathologie , Sujet âgé , Lésions encéphaliques/imagerie diagnostique , Femelle , Études de suivi , Hématome subdural/imagerie diagnostique , Humains , Tomodensitométrie , Plaies et blessures/imagerie diagnostique
8.
Acta Neurochir (Wien) ; 133(1-2): 50-5, 1995.
Article de Anglais | MEDLINE | ID: mdl-8561036

RÉSUMÉ

Since 1988 in the referral area of the Neurosurgical Unit of Cesena, Italy, a protocol for prevention of deterioration in minor head injury was adopted. Adult patients admitted to any hospital with a GCS score of 15 and 14 (transient) without neurological deficit are submitted to skull x-ray: if a fracture is present the patient is sent for CT to the nearest regional Center. In children skull x-ray is not routinely performed and the patients are admitted for observation to the nearest regional hospital. To assess the effects of such a protocol on morbidity and mortality of extradural haematoma (EDH), from June 1989 to September 1991 a consecutive series of 95 patients harbouring a significant acute EDH was collected. Mean age was 31 years; in 70% trauma was caused by a road traffic accident. The patients were divided into 3 categories: a) Clinical deterioration: mean GCS at surgery was 7.7; out of 27 patients, 12 had anysocoria and 3 bilaterally fixed pupils; the outcome showed only two deaths, one related to the EDH and the other to cardiac arrythmia. Most of the patients deteriorated either during transport after being recognized as at risk or already in Neurosurgery allowing rapid surgical treatment. b) Impaired consciousness (18 cases) and c) Minor head injury (50 cases) are groups of patients treated without morbidity and mortality. If we compare these results with those of a previous study of our group done in 1980-86, there is a statistically significant difference concerning both mortality and morbidity. Our protocol proved therefore to be adequate in preventing most deaths that occurred following clinical deterioration in an apparently low risk patient.


Sujet(s)
Traumatismes crâniens fermés/diagnostic , Hématome épidural intracrânien/diagnostic , Adolescent , Adulte , Sujet âgé , Enfant , Enfant d'âge préscolaire , Femelle , Échelle de coma de Glasgow , Traumatismes crâniens fermés/mortalité , Traumatismes crâniens fermés/chirurgie , Hématome épidural intracrânien/mortalité , Hématome épidural intracrânien/chirurgie , Mortalité hospitalière , Humains , Nourrisson , Italie/épidémiologie , Mâle , Adulte d'âge moyen , Fractures du crâne/diagnostic , Fractures du crâne/mortalité , Fractures du crâne/chirurgie , Taux de survie , Tomodensitométrie
9.
J Neurosurg Sci ; 38(2): 129-30, 1994 Jun.
Article de Anglais | MEDLINE | ID: mdl-7891194

RÉSUMÉ

The authors present the case of a 26-yrs-old woman admitted into our hospital after a severe polytrauma with a mild head injury. CT scanning disclosed two small hemorrhages located in her brainstem and mesial temporal lobe. After splenectomy the patient made a full recovery without neurological sequelae. Radiological signs of diffuse axonal injury even in the brainstem may be present in a clinically mild head injury.


Sujet(s)
Axones , Tronc cérébral/traumatismes , Hémorragie cérébrale , Traumatismes cranioencéphaliques/complications , Lobe temporal/traumatismes , Accidents de la route , Adulte , Tronc cérébral/vascularisation , Tronc cérébral/imagerie diagnostique , Hémorragie cérébrale/imagerie diagnostique , Hémorragie cérébrale/étiologie , Femelle , Échelle de coma de Glasgow , Humains , Rate/traumatismes , Splénectomie , Lobe temporal/vascularisation , Lobe temporal/imagerie diagnostique , Tomodensitométrie
14.
Neurochirurgie ; 29(4): 285-7, 1983.
Article de Français | MEDLINE | ID: mdl-6633775

RÉSUMÉ

The authors report an uncommon case of hemiballism following head injury. A CAT-scanning had been carried out. They consider that changes in the brain micro-vascular bed are a very important cause of hemiballism. They cannot confirm the influence of neuro-chemical alterations which are reported by many authors.


Sujet(s)
Traumatismes cranioencéphaliques/complications , Troubles de la motricité/étiologie , Adulte , Traumatismes cranioencéphaliques/imagerie diagnostique , Humains , Mâle , Tomodensitométrie
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