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F Roelants

Publications and source records attributed to F Roelants.

10 recordsLinked to original sources

[Uncommon cause of respiratory distress in the post-anaesthesia care unit].

We report a case of respiratory distress in the post anesthesia care unit following general anaesthesia for a dilatation and curettage related to miscarriage in a 32-year-old woman. The preoperative physical examination showed no abnormalities except for the presence of dry cough during the preceding two or three days. A few minutes after her arrival in the PACU, the patient developed hyperthermia till 40.6 degrees C, cough, polypnea and oxygen desaturation (SpO(2): 82% on FiO(2): 40%). A thoraco-abdominal angioscanner showed pulmonary basal condensations and a thrombosis of the right ovarian vein. The patient had to be transferred to the intensive care unit where she remained intubated and ventilated during 13 days because of a Haemophilus influenzae pneumonia.

Adult↗

[The sleep obstructive apnea and hypopnea syndromes].

Since two decades, sleep breathing disorders are more wisely recognized by the Belgian medical community. Among these, the Obstructive Sleep Apnea Syndrome (OSA) is the best known but its frontiers with others syndromes such as the Upper Airway Resistance Syndrome (UARS), the Central Sleep Apnea Syndrome (CSAS) or the Overlap Syndrome are still matter of discussion. Its causes are plurifactorial, and many recent publications draw the attention to its long term effects in the cardiovascular and neuropsychiatric fields. This article summarizes the present definitions and features associated with OSA, from clinical and neurophysiological perspectives, and the different consequences to which untreated or underdiagnosed patients are exposed.

Cardiovascular Diseases↗

[Diagnosis of internal carotid artery dissection. Two case reports].

Two cases of acute internal carotid dissection are presented. Typical symptoms, pathogeny and imaging features are reviewed. Magnetic Resonance is actually the best technique for the diagnosis of internal carotid artery dissection, which should be searched in young patients presenting neurologic and cervico-facial symptoms.

Age Factors↗

[Narcolepsy-cataplexy].

The diagnosis of narcolepsy-cataplexy is based on three axes: 1) the medical history is strongly suggestive when diurnal sleep attacks (narcolepsy) and drop attacks (cataplexy) are reported or observed; 2) the polysomnography is mandatory and shows nocturnal and diurnal (multiple sleep latency test) REM sleep onsets; 3) HLA typing, practically helps to exclude the diagnosis when HLA DR15-DQB1*0602 is not present. New pathogenetic hypotheses have been proposed, mostly based the absence of hypocretin in narcoleptic cerebrospinal fluid. This neurotransmitter was previously known exclusively by its involvement in alimentary behaviours. The new therapies remain symptomatic, but they are powerful to prevent somnolence, daytime sleepiness, cataplexy and insomnia associated with this syndrome.

Carrier Proteins↗

Patient-controlled intravenous analgesia using remifentanil in the parturient.

PURPOSE: To show the use of the short acting opioid remifentanil for labour analgesia when epidural analgesia is considered to be contraindicated. CLINICAL FEATURES: After Ethics Committee approval and informed consent, six patients (36-40 wk gestation), in whom epidural analgesia was considered contraindicated (women refusing regional analgesia, presenting with coagulation or platelet abnormalities or sepsis) benefited from patient-controlled intravenous analgesia (PCIA) with remifentanil. The Abbott Lifecare patient-controlled analgesia (PCA) pump with remifentanil 50 microg x ml(-1) was set to deliver remifentanil continuous background infusion of 0.05 microg x kg(-1) x min(-1) and 25 microg boluses with a five minutes lockout period. The PCIA was started when the parturients experienced regular painful contractions (cervical dilatation of at least 4 cm) and stopped just before delivery (cervix fully dilated). Maternal monitoring included non-invasive blood pressure measurements, heart rate, percutaneous arterial oxyhemoglobin saturation and respiratory rate. Percutaneous fetal heart rate was continuously monitored. All patients remained alert or sleepy but easily arousable and were satisfied with their analgesia. No particular side effects have been noticed. Apgar scores were between 6 and 10. CONCLUSION: Remifentanil PCIA combining low continuous background infusion and small bolus doses is an alternative when epidural analgesia in labour is contraindicated. Under careful anesthesia monitoring, the technique seems to be safe for both mother and baby, at least when delivery occurs at or near the normal term of pregnancy.

Adult↗

Delta sequence of Ty1 transposon can initiate transcription of the distal part of the URA2 gene complex in Saccharomyces cerevisiae.

Expression of a silent aspartate transcarbamylase (ATCase) domain can occur by insertion of a Tyl retrotransposon within the coding sequence of a mutated ura2 allele. This unusual type of Ty-mediated gene activation is possible as the URA2 gene product is a multifunctional protein containing the carbamoyl phosphate synthetase (CPSase), the ATCase and a cryptic dihydroorotase (DHOase) domain. The region in which transcription of the corresponding allele is initiated was determined by RT-PCR experiments. Expression is initiated by a sequence located in the delta element of the Tyl and not by a sequence of the URA2 gene itself. This situation differs with the Ty-mediated gene activation described thus far, in which the transposon substitutes only the 5' regulatory sequences and in which the normal transcription start point is used. The corresponding protein carries both the DHOase-like domain and the ATCase domain, suggesting that the DHOase-like domain is at least involved in the architecture of the protein and necessary to render the ATCase domain functional.

Alleles↗

Reactivation of the ATCase domain of the URA2 gene complex: a positive selection method for Ty insertions and chromosomal rearrangements in Saccharomyces cerevisiae.

Genetic rearrangements such as deletions or duplications of DNA sequences are rarely detected in the yeast Saccharomyces cerevisiae. We have developed a screening system using the URA2 gene coding for the bi-functional CPSase-ATCase (carbamyl phosphate synthetase - aspartate transcarbamylase) to select positively for these kinds of events. Nonsense mutations in the CPSase region cause a complete loss of the ATCase activity because of their strong polar effect. Thirty-seven ATCase+ revertants were isolated from a strain containing three nonsense mutations in the proximal CPSase region. Genetic and structural analysis of the URA2 locus in these strains allowed us to characterize two major classes of revertants. In the first, an entire copy of a Ty transposon was found to be inserted in the CPSase coding domain. This event, which represents a new form of Ty-mediated gene activation was further analysed by mapping the Ty integration site in 26 strains. In a second class of revertants, we observed chromosomal rearrangements and, in particular, duplication of the ATCase region and its integration in a new chromosomal environment in which this sequence becomes active.

Aspartate Carbamoyltransferase↗

Recovery of gene function by gene duplication in Saccharomyces cerevisiae.

A prototroph revertant (Rev9) selected from an ATCase- mutant of the URA2 gene containing three nonsense mutations was shown to contain two ATCase coding sequences. We cloned both ATCase coding areas to show that the duplicated locus (dl9) was the only functional one. Its size corresponded roughly to the second half of the URA2 wild-type gene. Sequence analysis of the 5' end of dl9 indicated that this duplicated sequence was inserted within the intergenic region close to the MRS3 gene and was transcribed from an unknown promoter divergently from the MRS3 gene. The event leading to the revertant strain Rev9 included a rearrangement that increased the size of chromosome X by about 60 kb. In agreement with such a rearrangement, recombination was undetectable in the vicinity of the locus dl9. Genetic mapping confirms that the MRS3 gene is 2 cM distal to the URA2 gene on the right arm of chromosome X.

Aspartate Carbamoyltransferase↗