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PubMed1994

Two distinct P element subfamilies in the genome of Drosophila bifasciata.

The genome of Drosophila bifasciata harbours two distinct subfamilies of P-homologous sequences, designated M-type and O-type elements based on similarities to P element sequences from other species. Both subfamilies have some general features in common: they are of similar length (M-type: 2935 bp, O-type: 2986 bp), are flanked by direct repeats of 8 bp (the presumptive target sequence), contain terminal inverted repeats, and have a coding region consisting of four exons. The splice sites are at homologous positions and the exons have the coding capacity for proteins of 753 amino acids (M-type) and 757 amino acids (O-type). It seems likely that both types of element represent functional transposons. The nucleotide divergence of the two P element subfamilies is high (31%). The main structural difference is observed in the terminal inverted repeats. Whereas the termini of M-type elements consists of 31 bp inverted repeats, the inverted repeats of the O-type elements are interrupted by non-complementary stretches of DNA, 12 bp at the 5' end and 14 bp at the 3' end. This peculiarity is shared by all members of the O-type subfamily. Comparison with other P element sequences indicates incongruities between the phylogenies of the species and the P transposons. M-type and O-type elements apparently have no common origin in the D. bifasciata lineage. The M-type sequence seems to be most closely related to the P element from Scaptomyza pallida and thus could be considered as a more recent invader of the D. bifasciata gene pool. The origin of the O-type elements cannot be unequivocally deduced from the present data.(ABSTRACT TRUNCATED AT 250 WORDS)

Amino Acid Sequence↗
PubMed1985

Correlations between the quantity of cerebral flow, brain surface pO2, and EEG in the dog.

Complete cerebral ischemia was carried out in 19 dogs by repeated occlusion of the large neck arteries. The interruption of cerebral blood flow (CBF) was controlled with the electric silence recorded on EEG and the rapid fall of brain surface oxygen tension (bspO2). A critical flow was determined in each experiment by release of clamping of one artery (left carotid artery), which seemed effective not only to stop the decrease of bspO2 but also to ensure the reappearance of EEG waves. This crucial value of carotid artery flow (CAF) was 49 ml/min and 38 ml/min after the first and second occlusions, respectively. The EEG changes during different phases of experiments were stored on magnetic tape and analyzed by computer. The distribution of the analyzed power spectrum of EEG provides a special characterization of brain function. Strict correlations are found between the actual blood flow and the changes of EEG and bspO2. Either alteration of the recorded two parameters can accurately reflect the possibility of brain recovery during and after short-lasting ischemia.

Animals↗
PubMed2001

MsqTc3, a Tc3-like transposon in the yellow fever mosquito Aedes aegypti.

A novel transposon, MsqTc3-Aa, has been discovered in the yellow fever mosquito, Aedes aegypti. Evidence of its past mobility is presented. There are approximately 100 copies of MsqTc3-Aa in A. aegypti, eight of which have been isolated and sequenced. All sequenced copies are more than 99% identical to their consensus, indicating recent mobilization. The MsqTc3-Aa consensus contains imperfect terminal inverted repeats (TIRs) and an open reading frame (ORF) interrupted by an intron. Sequence, structural and phylogenetic analysis showed that MsqTc3-Aa is a distant relative of Tc3, an active transposon in Caenorhabditis elegans. These results may provide useful information for the current effort to control mosquito-borne diseases using genetic approaches.

Aedes↗
PubMed1991

Human type VII collagen: cDNA cloning and chromosomal mapping of the gene.

A human keratinocyte cDNA expression library in bacteriophage lambda gt11 was screened with the purified IgG fraction of serum from a patient with epidermolysis bullosa acquisita, which had a high titer of anti-type VII collagen antibodies. Screening of approximately 3 x 10(5) plaques identified 8 positive clones, the largest one (K-131) being approximately 1.9 kilobases in size. Dideoxynucleotide sequencing of K-131 indicated that it consisted of 1875 base pairs and contained an open reading frame coding for a putative N-terminal noncollagenous domain of 439 amino acids and a collagenous C-terminal segment of 186 amino acids. The collagenous domain was characterized by repeating Gly-Xaa-Yaa sequences that were interrupted in several positions by insertions or deletions of 1-3 amino acids. The deduced amino acid sequence also revealed a peptide segment that had a high degree of identity with a published type VII collagen protein sequence. Northern hybridization of the K-131 cDNA with human epidermal keratinocyte and skin fibroblast RNA revealed an mRNA of approximately 8.5 kilobases. The fusion protein produced by the K-131 cDNA, when incubated with epidermolysis bullosa acquisita serum, bound to antibodies that reacted in Western blots with type VII collagen. The genomic location of the type VII collagen gene (COL7A1) was determined by chromosomal in situ hybridization with the K-131 cDNA. The results mapped the COL7A1 to the locus 3p21. The cDNA clones characterized in this study will be valuable for understanding the protein structure and gene expression of type VII collagen present in anchoring fibrils and its aberrations in the dystrophic forms of heritable epidermolysis bullosa.

Amino Acid Sequence↗
PubMed1996

Comparison of dobutamine stress echocardiography with dipyridamole stress echocardiography for detection of viable myocardium after myocardial infarction treated with thrombolysis.

OBJECTIVE: To compare the ability of dobutamine and dipyridamole stress echocardiography to detect functional recovery of stunned but viable myocardial regions early after acute myocardial infarction, and to predict late functional recovery of the reperfusion salvaged myocardium within the infarct area. METHODS: Within 10 d of acute myocardial infarction, 51 patients--30 anterior and 21 inferior, 44 Q wave and seven non-Q-wave infarction--were submitted to a dobutamine echocardiography test at low dose (5-10 micrograms/kg/min over 5 min) and high dose (20-40 micrograms/kg/min over 3 min) and to dipyridamole echocardiography test (0.56 mg/kg over 4 min + 0.28 mg/kg over 2 min) on different days and in random order, after interruption of any vasoactive drug. Resting echocardiography was repeated at two months in 41 of 51 patients (80%). Regional wall motion of the left ventricle was analysed in a semiquantitative manner on a 14-segment model. Viability was defined as improvement of one grade or more of at least two basally asynergic segments in the infarcted area. RESULTS: Regional functional recovery was detected by low dose dobutamine in 38/51 patients (75%) and in 147/308 (48%) of basally asynergic segments, compared to 25/51 patients (49%; P < 0.001) and 78/308 segments (25%; P < 0.001) only identified by dipyridamole. Late spontaneous functional recovery was detected in 24/41 patients (59%) and in 78/254 basally asynergic segments (31%). The sensitivity of dobutamine and dipyridamole echocardiography for predicting spontaneous functional recovery was 72% and 51% respectively (P < 0.001), specificity 68% and 82% (P < 0.001), positive predictive value 50% and 56%, and negative predictive value 85% and 79%. CONCLUSIONS: In comparison with dipyridamole in patients with thrombolysed myocardial infarction, dobutamine induces regional functional recovery. This suggests that dobutamine is more sensitive in showing the presence of viable myocardium within the infarct zone, though it has a lower specificity in predicting delayed spontaneous functional recovery of non-contractile but still viable areas.

Coronary Angiography↗
PubMed2001

Effects of heat and cold application on turns and amplitude in surface EMG.

The purpose of this study was to investigate the effects of cooling and heating of muscles on parameters of surface EMG (SEMG) under various well defined grades of isometric muscle contraction. In 32 healthy volunteers, aged 20-30 years, turns and amplitude (RMS) analysis was done in SEMG from the hand extensors. Muscle strength was defined by a new developed hand dynamometer. Values for RMS and turns in case of maximal voluntary contraction (MVC) over periods of 20 sec were determined for each volunteer and subsequently RMS and turns were measured during isometric contractions of 10%, 30%, 50% and 80% of MVC, interrupted each by rest periods. This procedure was repeated after cooling and warming the forearm with thermo packs. For control purposes the same investigations with three measurement periods of SEMG were done following the same time schedule without thermic stimuli. With increasing isometric contractions turns increased after heat application and decreased after ice application, compared to the values achieved without thermic stimuli. The differences were significant from a level of 30% of MVC (p < 0.05). No corresponding changes were seen for RMS. In the control experiment values of turns and RMS did not differ in the three measurement periods. It is concluded, that the amplitude in SEMG tracings seems to be a reliable parameter of muscle force, whereas turns are sensitive to temperature. They might be useful markers for therapeutic approaches targeted at the muscle.

Adult↗
PubMed1979

Inhibitory role of brain stem serotoninergic neuron system on thyroid function in rat.

Thyroid function was investigated in adult male rats following the use experimental procedures which inhibit the activity of serotoninergic neuron system. Pharmacological blockade of the biosynthesis of sertonin by repeated administration of para-chlorophenylalanine (pCPA), or interruption (by Halász knife) of the serotoninergic pathways of the brain stem which terminate on hypothalamic nuclei equally resulted in an augmentation of the following parameters of hypothalamo-hypophysial-thyroid activity: T/S ratio, pituitary and blood TSH levels and blood thyroxine concentration as well as TRH content of the hypothalamus. The results suggest that the central nervous serotoninergic neuron system plays an inhibitory role in the regulation of TSH secretion, presumably acting upon the hypothalamus, thereby inhibiting hypothalamic TRH secretion.

Animals↗
PubMed1991

[Growth of the aortic anastomosis in puppies--comparison of monofilament suture materials, whether absorbable or nonabsorbable, and of suture techniques, whether continuous or interrupted].

This study compared the growth of vascular anastomoses performed with either polypropylene or polydioxanone sutures and with either continuous running suture or interrupted suture technique. Primary end-to-end anastomoses of the infrarenal aorta were performed in 38 puppies. Nineteen were performed with 5-0 polypropylene sutures; in ten all sutures were placed in continuous fashion, and in nine in interrupted fashion. The other nineteen were performed with 5-0 polydioxanone sutures; in ten the sutures were placed in continuous fashion, and in nine in interrupted fashion. The animals were subjected to the repeated aortograms at 2, 4, 8 weeks, 6 months and 1 year following operation. Each abdominal aorta was subjected to burst test, and pathological examination. All anastomoses were patent and tolerated burst-test (300 mmHg). Neither aneurysm nor dilatation of anastomotic site was observed. Anastomotic area was significantly smaller and more stenotic in the continuous polypropylene suture group than in other three groups at 8 weeks, 6 months and 1 year following operation. There was no significant difference among these three groups. No suture materials were observed in the polydioxanone suture groups after 6 months following operation. This study suggests that polydioxanone suture will be useful for the repair of cardiovascular anomalies where growth of the suture line is required.

Absorption↗
PubMed1984

Isolation and characterization of a cDNA clone for the amino-terminal portion of the pro-alpha 1(II) chain of cartilage collagen.

We have isolated a cDNA clone (pRcol 2) which is complementary to the 5'-terminal portion of the rat pro-alpha 1(II) chain mRNA. A synthetic oligonucleotide was used both as a primer for cDNA synthesis and as a probe for screening a cDNA library. The probe was a mixture of sixteen 14-mers deduced from an amino acid sequence present in the amino-terminal telopeptide of the rat cartilage alpha 1(II) chain. This primer was chosen so that the resulting cDNA would contain the sequence of the 5' end of the mRNA. The nucleotide sequences of the cDNA were determined and compared with that of three other interstitial procollagen chain mRNAs (pro-alpha 1(I), pro-alpha 2(I), and pro-alpha 1(III) chain mRNA). pRcol 2 contains a 521-base pair (bp) insert, including 153 bp of the 5' untranslated region plus 368 bp coding for the signal peptide, the amino-terminal propeptide, and a part of the telopeptide. The signal peptide of the type II collagen chain is composed of about 20 amino acids. There is little homology between the amino acid sequence of the signal peptide in the pro-alpha 1(II) chain and that of three other interstitial procollagen chains. The NH2-terminal propeptide is deduced to contain short nonhelical sequences at its amino and carboxyl ends and an internal helical collagenous domain comprising 25 repeats of Gly-X-Y with one interruption. There is a strong conservation of the amino acid sequence of the carboxyl-terminal part of the NH2-terminal propeptide in the pro-alpha 1(II), pro-alpha 1(I), and pro-alpha 2(I) chains. Type II collagen mRNA does not contain a sequence corresponding to a uniquely conserved nucleotide sequence around the translation initiation site which occurs in mRNA for other procollagen chains.

Amino Acid Sequence↗
PubMed1994

Biofeedback treatment of children and adults with idiopathic detrusor instability.

In adults and children suffering from urge, urge incontinence, frequent voidings, and nocturia, urodynamic examination often confirms the diagnosis of detrusor instability. We assessed the outcome of biofeedback therapy in 15 children aged 6-12 years and 7 adults aged 20-52 years, all with cystometrically proven detrusor instability. The detrusor pressure was visually conveyed to the patient during repeated bladder fillings. The patient was instructed to interrupt detrusor pressure increments by tensing the pelvic floor musculature. None of the children were found completely cured; however, 9 showed a marked decrease in either the number of the extent of symptoms. Two children showed moderate improvement, while 4 remained unaffected by the treatment. One adult was completely cured, 2 improved moderately, and 4 showed no improvement. None of these patients were converted to stable cystometry. Upon termination of the BF treatment a follow-up study was conducted for patients exhibiting pronounced or moderate improvement. The beneficial effect was maintained except in one case.

Adult↗
PubMed1994

[The echo-dobutamine and echo-dipyridamole tests in assessing vital myocardium and residual ischemia in myocardial infarct after thrombolysis].

The aim of the study was to compare the ability of dobutamine and dipyridamole echocardiography to detect stunned but viable myocardium early after acute myocardial infarction, to predict spontaneous functional recovery of the reperfused myocardium at 2 months and to detect myocardial ischemia in the infarcted area. Within 10 days from acute myocardial infarction, 47 patients, 29 anterior and 18 inferior, 41 Q-wave and 6 non Q-wave infarctions, underwent dobutamine echocardiography test at low-dose (5-10 mcg/kg/min over 5 min) and high-dose (20-40 mgc/kg/min over 3 min) and to dipyridamole echocardiography test (0.56 mg/kg over 4 min + 0.28 mg/kg over 2 min) in different days and in random order, after interruption of any vasoactive drug. Resting echocardiography was repeated at 2 months in 38/47 patients. Regional wall motion analysis was performed in a qualitative manner on a 14-segment model; viability was defined as improvement of 1 grade or more of at least 2 basally asynergic segments in the infarcted area. Ischemia was defined as an improvement followed by significant deterioration of contractility of the infarcted segments or deterioration of the infarcted area. All patients underwent coronary arteriography within 1 month from admission. Viability was detected by low-dose dobutamine in 34/47 patients (72%) and in 131/297 (44%) of basally asynergic segments compared to only 21/47 patients (45%) and in 66/297 segments (22%) detected by dipyridamole; myocardial ischemia was induced by dobutamine in 64% of patients compared to 36% by dipyridamole. Late spontaneous functional recovery was detected in 21/38 patients (57%) and in 70/244 (29%) of asynergic segments. Sensitivity of dobutamine and dipyridamole echocardiography for predicting spontaneous functional recovery was 70% and 46% specificity 69% and 83%, positive predictive value 48% and 52%, negative predictive value 85% and 79% respectively. Dobutamine correctly identified the presence of a significant stenosis of the infarct-related artery in 74% of cases compared with 43% of dipyridamole; specificity for detecting stenosis was 67% for dobutamine and 83% for dipyridamole. In conclusion, in patients with thrombolyzed myocardial infarction dobutamine echocardiography detects viable myocardium with late spontaneous recovery in a greater proportion of patients and segments than dipyridamole; dobutamine has a higher sensitivity but a lower specificity compared to dipyridamole for identifying a residual stenosis of the infarct-related artery that may jeopardize myocardium in the area at risk.

Adult↗
PubMedDate not supplied

[Attempt at evaluation of the risk of mortality in utero].

An analysis was made of the obstetric history of 1,360 patients who were delivered in 1971. It involved 3,185 pregnancies. The aim of the study was to evaluate the risk of spontaneous termination of the pregnancy, worked out from its demographic aspect. Several ideas are worthy of consideration. The risk of spontaneous intra-uterine death is cumulative, sharply increased by a repetition of such cessation of pregnancy. The same patients often undergo intentional abortion repeatedly. The respective risks of spontaneous and provoked interruption of pregnancy have been studied in greater detail as a function of parity.

Abortion, Induced↗
PubMed2003

Distribution of CGG repeat sizes within the fragile X mental retardation 1 (FMR1) homologue in a non-human primate population.

Fragile X syndrome, the most common inherited form of mental retardation, arises in individuals with more than 200 CGG repeats in the 5' untranslated region of the fragile X mental retardation 1 ( FMR1) gene. Although CGG repeat numbers comparable to those found in the normal human population are found in various non-human primates, neither the within-species size variation nor the propensity for expansion of the CGG repeat has been described for any non-human primate species. The allele distribution has now been determined for FMR1 (homologue) CGG repeats of 265 unrelated founder females of Macaca mulatta monkeys. Among 530 X chromosomes, at least 26 distinct repeat lengths were identified, ranging from 16 to 54 CGG repeats. Of these alleles 79% have between 25 and 33 CGG repeats. Detailed examination of the CGG region revealed a conserved G (CGG)(2 )G interruption, although in no case was an AGG trinucleotide detected. Two animals carried borderline premutation alleles with 54 CGG repeats, within the region of marginal instability for humans. Thus, M. mulatta may be useful as an animal model for the study of fragile X syndrome.

Alleles↗
PubMed2001

The inverted repeats of IS1384, a newly described insertion sequence from Pseudomonas putida strain H, represent the specific target for integration of IS1383.

Analysis of a region on plasmid pPGH1 from Pseudomonas putida strain H that is flanked by two copies of IS1383 has revealed an additional element with the typical features of a bacterial insertion sequence. This new IS element, designated IS1384, contains a single ORF of 972 bp, and is flanked by 9-bp inverted repeats. Based on sequence homology and structural characteristics of the putative transposase it encodes, IS1384 belongs to the IS5 subgroup of the IS5 family. Two copies of IS1384 are present on plasmid pPGH1, whereas none could be detected on the chromosome of P. putida strain H. Sequence analysis revealed the presence of two truncated copies of IS1384 on the second plasmid in this strain, pPGH2. The inverted repeats of all IS1384 copies (including the truncated ones) are interrupted by the integration of an IS1383 element. All integrations were found to be site- and orientation-specific. PCR studies and sequence data indicate that IS1383 can form a circular intermediate on excision. In the circular form, the previously described 13-bp inverted repeats of IS1383 are separated by 10 bp that are identical to the 5-bp motif that flanks each side of the element when it is integrated in its target. We provide evidence that these additional nucleotides, although not of inverted symmetry, represent an essential part of the inverted repeats. Furthermore, the data indicate that IS1383 integrated into the inverted repeats of IS1384 by a site-specific recombination rather than a site-specific insertion event.

Base Sequence↗
PubMed1986

The molecular through ecological genetics of abnormal abdomen. II. Ribosomal DNA polymorphism is associated with the abnormal abdomen syndrome in Drosophila mercatorum.

Restriction endonuclease cleavage analyses of cloned and genomic DNA samples indicate that the structure of the DNA encoding the large cytoplasmic RNAs (rDNAs) is altered in Drosophila mercatorum lines which exhibit an abnormal abdomen (aa) phenotype. In a majority of the rDNA repeat units from aa flies, the 28S coding sequence is interrupted by a large [5-6 kilobase pairs (kbp)] insert. A subclone containing this inserted DNA (ins 3) hybridizes primarily to rDNA-containing sequences in in situ and genomic blot hybridization experiments. Additionally, genomic nitrocellulose blot hybridization analyses show that ins- containing rDNA repeat units are clustered in a spontaneously arising aa mutant. This rDNA alteration in D. mercatorum flies with the aa phenotype more closely resembles the bobbed (bb) defect of D. hydei than the bb defect of D. melanogaster, which involves alterations in rDNA copy number. By analogy with the other Drosophila systems, we propose that the altered D. mercatorum rDNA repeat units are defective in rRNA production at a critical stage. The lowered levels of rRNA ultimately would limit the concentration of ribosomes needed to produce large quantities of a protein (in these cases, juvenile hormone esterase) needed for normal development.

Abdomen↗
PubMed2004

Insertion of telomeric repeats at intrachromosomal break sites during primate evolution.

Short blocks of telomeric-like DNA (Interstitial Telomeric Sequences, ITSs) are found far from chromosome ends. We addressed the question as to how such sequences arise by comparing the loci of 10 human ITSs with their genomic orthologs in 12 primate species. The ITSs did not derive from expansion of pre-existing TTAGGG units, as described for other microsatellites, but appeared suddenly during evolution. Nine insertion events were dated along the primate evolutionary tree, the dates ranging between 40 and 6 million years ago. Sequence comparisons suggest that in each case the block of (TTAGGG)n DNA arose as a result of double-strand break repair. In fact, ancestral sequences were either interrupted precisely by the tract of telomeric-like repeats or showed the typical modifications observed at double-strand break repair sites such as short deletions, addition of random sequences, or duplications. Similar conclusions were drawn from the analysis of a chimpanzee-specific ITS. We propose that telomeric sequences were inserted by the capture of a telomeric DNA fragment at the break site or by the telomerase enzyme. Our conclusions indicate that human ITSs are relics of ancient breakage rather than fragile sites themselves, as previously suggested.

Animals↗
PubMed2004

A new insight into fragile X syndrome among Basque population.

The expansion of a trinucleotide repeat [CGG]n located in the FMR1 X-linked gene is the main cause of fragile X syndrome, the most common form of inherited mental retardation. We have analyzed the factors known, to date, to influence the instability of the repeat in 158 normal X chromosomes from the Spanish Basque population. These factors included length of the repeat, AGG interspersion pattern, length of uninterrupted CGG and DXS548-FRAXAC1 markers associated haplotype. Previous investigations on Basques showed an absence of this disorder among mentally retarded individuals that was likely due to a low prevalence of large CGG alleles and the presence of AGG interruptions on them. The present report suggests that, although the frequency of large alleles is low and they do maintain AGG interruptions, different mutational pathways that might lead to fragile X syndrome could be occurring among Basques. These pathways mainly include alleles with internal sequences 9 + 9 + n and 9 + 12 + 9 that show fragile X associated haplotypes. Besides, the lack of the most proximal AGG interruption, proposed recently as a novel factor involved in CGG repeat instability, was highly identified among alleles with long pure CGG tracts, which showed an internal sequence n + 9. The data suggest that, despite the lower incidence of large alleles, the prevalence of potentially unstable alleles among Basques is similar to that of other Caucasian populations and that these alleles could become fragile X chromosomes.

Fragile X Syndrome↗
PubMed1991

An adult male specific gene in Drosophila containing the repetitive element opa.

A cDNA has been isolated for an adult male specific gene in Drosophila that contains the repetitive element opa. We have named this gene Dromsopa for Drosophila male specific opa containing gene. The 0.6 kb mRNA for this gene is only found in the abdominal region of adult male Drosophila and in no other tissue or at other developmental stages. The Dromsopa opa repeat codes for the usual stretch of poly(glutamine) interrupted by histidine residues. The opa repetitive element was originally found in the Drosophila Notch gene (Kidd, S. et al. (1983) Cell 34, 431-433 and Wharton, K.A. (1985) Cell 40, 55-62) and has, more recently, been found in genes under developmental or tissue specific control from yeast to humans. The gene was cloned using a genomic fragment during a chromosomal walk upstream of the AP3 gene located at chromosomal location 79CD on the left arm of the third chromosome (Kelley, M.R. et al. (1989) Mol. Cell. Biol. 9, 965-973). The Dromsopa gene has no other identity with genes currently in the databases, once the opa repeat is excluded. The possibility that the Dromsopa gene is a male specific regulatory factor is under investigation as is its precise location within the abdomen, such as in germ line tissue.

Amino Acid Sequence↗