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F Nasr

Publications and source records attributed to F Nasr.

At least 37 records · Page 2Linked to original sources
PubMed1995

Artificial antisense RNA regulation of YBR1012 (YBR136w), an essential gene from Saccharomyces cerevisiae which is important for progression through G1/S.

YBR1012 (YBR136w) is an essential gene from Saccharomyces cerevisiae identified during the systematic sequencing of part of the right arm of chromosome II. We previously constructed a conditional allele of YBR1012 based on antisense RNA, by inserting a small fragment of this gene downstream from the inducible UASGAL10-CYC1 promoter. Several other antisense RNA constructions have since been made and their activity tested. The response of the system appears to be very delicate, as the presence or absence of 13 nucleotides of polylinker in the 300 nucleotide antisense transcript can dramatically modify its effectiveness. The most effective antisense RNA construction was used in flow cytometry studies to investigate the role of ybr1012p. The results show that during the antisense RNA block some 80% of the cells are arrested with their DNA unreplicated, suggesting that Ybr1012p is needed for progression through G1 or early S phase.

Cell Cycle↗
PubMed1994

Complete DNA sequence of yeast chromosome II.

In the framework of the EU genome-sequencing programmes, the complete DNA sequence of the yeast Saccharomyces cerevisiae chromosome II (807 188 bp) has been determined. At present, this is the largest eukaryotic chromosome entirely sequenced. A total of 410 open reading frames (ORFs) were identified, covering 72% of the sequence. Similarity searches revealed that 124 ORFs (30%) correspond to genes of known function, 51 ORFs (12.5%) appear to be homologues of genes whose functions are known, 52 others (12.5%) have homologues the functions of which are not well defined and another 33 of the novel putative genes (8%) exhibit a degree of similarity which is insufficient to confidently assign function. Of the genes on chromosome II, 37-45% are thus of unpredicted function. Among the novel putative genes, we found several that are related to genes that perform differentiated functions in multicellular organisms of are involved in malignancy. In addition to a compact arrangement of potential protein coding sequences, the analysis of this chromosome confirmed general chromosome patterns but also revealed particular novel features of chromosomal organization. Alternating regional variations in average base composition correlate with variations in local gene density along chromosome II, as observed in chromosomes XI and III. We propose that functional ARS elements are preferably located in the AT-rich regions that have a spacing of approximately 110 kb. Similarly, the 13 tRNA genes and the three Ty elements of chromosome II are found in AT-rich regions. In chromosome II, the distribution of coding sequences between the two strands is biased, with a ratio of 1.3:1. An interesting aspect regarding the evolution of the eukaryotic genome is the finding that chromosome II has a high degree of internal genetic redundancy, amounting to 16% of the coding capacity.

Base Composition↗
PubMed1994

Heterospecific cloning of Arabidopsis thaliana cDNAs by direct complementation of pyrimidine auxotrophic mutants of Saccharomyces cerevisiae. I. Cloning and sequence analysis of two cDNAs catalysing the second, fifth and sixth steps of the de novo pyrimidine biosynthesis pathway.

An Arabidopsis thaliana cDNA library was used to complement Saccharomyces cerevisiae pyrimidine auxotrophic mutants. Mutants in all but one (carbamylphosphate synthetase) of the six steps in the de novo pyrimidine biosynthetic pathway could be complemented. We report here the cloning, sequencing and computer analysis of two cDNAs encoding the aspartate transcarbamylase (ATCase; EC 2.1.3.2) and orotate phosphoribosyltransferase-orotidine-5'-phosphate decarboxylase (OPRTase-OMPdecase; EC 2.4.2.10, EC 4.1.1.23) enzymes. These results confirm the presence in A. thaliana of a bifunctional gene whose product catalyses the last two steps of the pyrimidine biosynthetic pathway, as previously suggested by biochemical studies. The ATCase encoding cDNA sequence (PYRB gene) shows an open reading frame (ORF) of 1173 bp coding for 390 amino acids. The cDNA encoding OPRTase-OMPdecase (PYRE-F gene) shows an ORF of 1431 bp coding for 476 amino acids. Computer analysis of the deduced amino acid sequences of both cDNAs shows the expected high similarity with the ATCase, ornithine transcarbamylase (OTCase; EC 2.1.3.3), OPRTase and OMPdecase families. This heterospecific cloning approach increases our understanding of the genetic organization and interspecific functional conservation of the pyrimidine biosynthetic pathway and underlines its usefulness as a model for evolutionary studies.

Amino Acid Sequence↗
PubMed1994

The sequence of 29.7 kb from the right arm of chromosome II reveals 13 complete open reading frames, of which ten correspond to new genes.

We have determined the complete nucleotide sequence of a 29.7 kb segment from the right arm of chromosome II carried by the cosmid alpha 61. The sequence encodes the 3' region of the IRA1 gene and 13 complete open reading frames, of which ten correspond to new genes and three (CIF1, ATPsv and CKS1) have been sequenced previously. The density of protein coding sequences is particularly high and corresponds to 84% of the total length. Two new genes encode membrane proteins, one of which is particularly large, 273 kDa. In one case (ATPsv), the comparison of our sequence and the published sequence reveals significant differences.

Adaptor Proteins, Signal Transducing↗
PubMed1994

An analysis of the sequence of part of the right arm of chromosome II of S. cerevisiae reveals new genes encoding an amino-acid permease and a carboxypeptidase.

We have analysed two new genes, YBR1007 and YBR1015, discovered during the systematic sequencing of chromosome II of S. cerevisiae. YBR1007 shows strong similarities to amino-acid permeases, in particular the high-affinity proline permeases of S. cerevisiae and A. nidulans. The number and position of the predicted membrane-spanning domains suggest a conserved structure for these proteins, with 12 trans-membrane domains. YBR1015 shows strong similarities to serine carboxypeptidases; all three residues of the "catalytic triad" typical of this family of enzymes are conserved in the YBR1015 protein. In a preliminary functional analysis we have created a null allele of the YBR1015 gene, and shown that it is not essential for cellular viability.

Amino Acid Sequence↗
PubMed1994

[Infections in cancer patients with granulocytopenia. Retrospective studies of 59 febrile episodes with hospitalization].

A total of 59 febrile neutropenic episodes were retrospectively recorded at Hôtel-Dieu de France Hospital between August 1st 1991 and December 31st 1992. These episodes were recorded in 51 cancer patients. Median neutropenia was less than one week in 50% of the cases. The etiology of these fever was documented in 27 episodes (46%) and in 70% of the cases gram (-) rods were documented. B-Lactam and Aminoglycoside antibiotics were used in 34 episodes at the initial treatment of these patients. Success rate at this initial treatment or with a modification of the antibiotic therapy was recorded in 85% of the patients. Only 15% of the patients failed to this antibiotherapy, 2/3 of them had their disease in progression. The systemic use of Amphotericine E in those patients with prolonged febrile neutropenia and the concommitent use of growth factors in a sub-group of patients at high risk could lead to a higher success rate in these patients.

Adult↗
PubMed1994

YBR1012 an essential gene from S. cerevisiae: construction of an RNA antisense conditional allele and isolation of a multicopy suppressor.

The gene YBR1012 was identified during the systematic sequencing of chromosome II of the yeast Saccharomyces cerevisiae. We have inactivated the gene and shown that it is essential for cellular viability. Using antisense RNA technology we have constructed a conditional allele, expression of the antisense RNA strongly inhibits growth. To our knowledge this is the first successful use of antisense RNA technology in S. cerevisiae. Comparison of the deduced ybr1012p sequence with the data banks revealed the presence of a putative phosphatidylinositol kinase domain and a strong homology to the Schizosaccharomyces pombe rad3p. These results suggest that ybr1012p may be involved in signal transduction, possibly related to the control of replication and/or DNA damage repair. The link with DNA damage repair was reinforced by the isolation of the DUN1 gene as a multicopy suppressor of the YBR1012 deletion.

Alleles↗
PubMed1993

Deletion scanning of the regulatory sequences of the Fbp1 gene of Drosophila melanogaster using P transposase-induced deficiencies.

A procedure permitting deletion scanning of potential cis-regulatory sequences within a transgene whose genomic position remains fixed was applied to the study of the upstream sequences of the ecdysteroid-inducible Fat-body-protein-1 (Fbp1) gene. Deficiencies were induced in a Fbp1:Adh fusion transgene by means of a secondary P transposase mutagenesis. Phenotypic and molecular screens were used to select mutant transposons that retained their original genomic location and carried a deletion affecting the Fbp1 sequences but not the Adh reporter gene. Molecular mapping of the deletion breakpoints was achieved by sequence analysis and expression of the reporter gene was quantified by measurement of ADH activity. This procedure was efficient in detecting cis-acting elements, even those with moderate effects on levels of gene expression. For example, we have succeeded in identifying a negative regulatory element. Deletion of this element leads to a 50% increase in the reporter ADH activity. This element binds the transcription factor AEF-1. In addition, we have detected a strong, positively acting element contained within a 32-bp region located immediately upstream of an ecdysone-response element.

Alcohol Dehydrogenase↗
PubMed1993

Juvenile reflex sympathetic dystrophy: a case report.

We report a case of reflex sympathetic dystrophy in a 10-year-old girl who presented with a two months history of severe pain and paresthesia in her right lower extremity. The patient made a very good recovery after two months of treatment with steroids and physical therapy.

Child↗
PubMed1985

Low antithrombin III and high plasma fibronectin in pre-eclampsia.

Antithrombin III activity and plasma fibronectin levels were determined in patients with preeclampsia. In several cases low antithrombin III and high plasma fibronectin concentrations could be related to proteinuria. Altered plasma fibronectin and antithrombin III concentrations might contribute to a hypercoaguable state in patients with preeclampsia.

Adolescent↗
PubMed1985

[Do pregnancy proteins have prospective significance? (SP-1, HPL and PP-5)].

Concentrations of pregnancy proteins were determined in blood of 219 pregnant women in 20th week of gestation. Pregnancy-specific beta 1-glycoprotein SP-1, human placental lactogen (hPL) and placental protein 5 (PP-5) were tested. In contrast with results of other authors there were no differences between the normal group of patients and those with complications during gestation, such as prematurity and foetal retardation. Thus measurement of blood concentration of proteins mentioned above in 20th week is not of prognostic relevance for gestation.

Female↗
PubMed1984

[Modification of cycle-dependent changes in the uterus by the intake of hormonal contraceptives].

In 15 women with normal biphasic cycles we measured the size of the uterus by means of ultrasound, weekly during one month. As comparison we used a group of 10 women with hormonal contraception. In normally menstruated women the shortest diameters of the corpus uteri were found at the end of the 2nd week of the cycle, the maximal increase size of about 25%, shortly before menstruation. In women with hormonal contraception no significant changes in size were found, obviously as a result of the decreased production of sexual steroids.

Adult↗
PubMed1984

[Modification of semen quality by acupuncture in subfertile males].

Our first attempt in treating subfertility by acupuncture was carried out on 28 males. The results obtained from the experiences in veterinary medicine encouraged us to attempt this type of therapy. Each patient received a total of 10 treatments for a period of three weeks. Several spermiograms were made after diagnosis subfertility. We checked spermiograms and hormone levels before and after acupuncture. Total count, concentration and motility were evaluated. In all cases we observed a statistically significant improvement of sperm quality. Having obtained these good results in our first studies, we now intend to continue acupuncture therapy in subfertile males for insemination or intercourse at the time of the ovulation of their female partners.

Acupuncture Therapy↗
PubMed1983

[Plasma fibronectin in normal pregnancy and EPH gestosis].

Plasma fibronectin was determined during normal pregnancy after 15th week, post partum, in cord blood and in cases of EPH gestosis. Non-pregnant women of a comparable age group were examined for plasma fibronectin concentration. Fibronectin at the end of gestation was at about the same level as at the beginning of the second trimester and as in non-pregnant women. The amount of fibronectin remains post partum practically the same. Cord blood fibronectin was about half the concentration of that in adult plasma. In EPH gestosis, levels were significantly elevated.

Adolescent↗
PubMed1983

[Plasmafibronectin in case of tumors of the female genital system].

The plasma concentration of fibronectin was measured by method of single radial immunodiffusion pretherapeutically in a group of 72 patients with different sites and various stages of gynecological carcinomas and of 27 women with benign cysts of ovary. A group of 18 healthy women was used for comparison. Fibronectin in plasma was significantly decreased in patients with ovarian tumors while in patients with other tumor localizations no significant difference to control group was evaluable.

Adult↗
PubMed1981

[SP-1 and beta-HCG in suspected ectopic pregnancy (author's transl)].

Serum levels of SP-1 and beta HCG as Trophoblastic Markers were measured in 31 women operated on suspected ectopic pregnancy. In all 24 patients with tubal pregnancy SP-1 levels estimated by enzyme immunoassay Enzygnost were higher than 5 ng/ml, whereas SP-1 levels in 7 cases with benign ovarian cysts were less than 2 ng/ml. Beta-HCG in serum was analysed by radioimmunoassay (Serono-Biodata): in cases with ectopic pregnancy serum levels were between 113 mIU/ml and 1040 mIU/ml, in the 7 nonpregnant cases the highest concentration was 7 mIU/ml. There was no correlation between serum concentration of SP-1 and beta-HCG (r = 0,571). In view of clinical practice preference is given to estimation of SP-1 by enzyme immunoassay over estimation of beta-HCG by radioimmunoassay, the reasons are discussed.

Chorionic Gonadotropin↗