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Results for “insertion, inversion”

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PubMed2002

Prevalence of small rearrangements in the factor VIII gene F8C among patients with severe hemophilia A.

Hemophilia A is a common X-linked bleeding disorder caused by various types of mutations in the factor VIII gene F8C. The most common intron 22-inversion is responsible for about 40% of the severe hemophilia A cases while large deletions, point mutations and small (less than 100 bp) deletions or insertions are responsible for the disease in the rest of patients. We report on nine novel (6 deletions, two indels and one partial duplication) and five recurrent small rearrangements identified in 15 German patients with severe hemophilia A, negative for the intron 22-inversion. c.2208-2214delTTATTAC/c.2207-2215insCTCTT and c.4665-4678del/c.4664-4678insAAGGAA identified in the present study are the first small indels described in the factor VIII gene. Our analyses suggest that the prevalence of this type of mutations (predominantly located in exon 14) among patients with severe phenotype and negative for the common intron 22-inversion, is about 30%. The correlation between these molecular defects and formation of factor VIII inhibitors as well as the parental origin of the de novo mutations are evaluated. Finally we show that denaturing HPLC (DHPLC) and classic heteroduplex analysis (HA) are able to detect these sequence alterations on 100% and could be preferred as a screening approach when analysing for mutations in factor VIII in severely affected patients.

Base Sequence↗

PubMed1999

Random transposition by Tn916 in Desulfitobacterium dehalogenans allows for isolation and characterization of halorespiration-deficient mutants.

To allow for the molecular analysis of halorespiration by the strictly anaerobic gram-positive bacterium Desulfitobacterium dehalogenans, halorespiration-deficient mutants were selected and characterized following insertional mutagenesis by the conjugative transposon Tn916. To facilitate rapid screening of transconjugants, a highly efficient method for the growth of single colonies on solidified medium has been developed. A streptomycin-resistant mutant of D. dehalogenans was isolated and mated with Enterococcus faecalis JH2-2 carrying Tn916. Insertion of one or two copies of Tn916 into the chromosome of D. dehalogenans was observed. From a total of 2,500 transconjugants, 24 halorespiration-deficient mutants were selected based upon their inability to use 3-chloro-4-hydroxyphenylacetic acid as an electron acceptor. Physiological characterization led to the definition of three phenotypic classes of mutants that differed in their ability to use the additional terminal electron acceptors nitrate and fumarate. The activities of hydrogenase and formate dehydrogenase were determined, and the transposon insertion sites in selected mutants representing the different classes were analyzed on the sequence level following amplification by inverse PCR. The results of the molecular characterization as well as the pleiotropic phenotypes of most mutants indicate that genes coding for common elements shared by the different respiratory chains present in the versatile D. dehalogenans have been disrupted.

Bacteria, Anaerobic↗

PubMed2003

Selective polarization inversion of protons in rotating solids.

The selective inversion of lines under phase modulated Lee-Goldburg (PMLG) decoupling in MAS proton spectroscopy is demonstrated. Short pulses inserted between consecutive PMLG irradiation intervals selectively invert the polarization of an on-resonance line while sustaining a high resolution proton evolution. The pulse scheme is combined with windowed-PMLG detection to obtain a one-dimensional high resolution spectrum with one of the proton lines inverted. Initial preparation of the protons in selectively inverted states can be used to follow the flow of polarization during spin diffusion. Examples of proton-proton spin exchange in alanine and histidine are demonstrated. Selective inversion is also used in conjunction with proton carbon LG-cross-polarization to achieve carbon spectra with lines characterized by different polarization states.

Alanine↗

PubMed1994

[The mechanism of the interchromsomal effect on crossing over in Drosophila melanogaster: delayed crossing over].

Interchromosomal effect on crossing-over (IEC) in autosome 2 has been studied in 2/F(2L); F(2R) females heterozygous for free arms (acrocentrics) and in Is(Y;2)419/+ females with an insertion of Y-material into the region 34A. IEC was induced by In(1)dl-49 + BM1 inversion. Manifestations of IEC included increased recombinational length of chromosome 2 and decreased interference. IEC was not observed in Df(2L)TW161/+ females with 38A-40 deletion. The patterns of IEC in three types of gametes of the 2/F(2L); F(2R) female depended on the pairing relations of the affected chromosome (chromosome-responder). In the case of normal pairing between the metacentric autosome 2 (the metacentric) and the F(2R) acrocentric, the increment in 2R length was minimal (20%), and the increment in the proportion of multiple-exchange (high-rank) tetrads (E2 + E3), maximal (8 to 10%). In the case of disturbed pairing 2-F(2R) nondisjunction, 2R length was increased by 77%, paralleled by a minimal increase in the proportion of high-rank tetrads (4%). Similarly, in females with the insertion, a pronounced increase in 2L length (74%) was associated with a moderate level of high-rank tetrads. When pairing in the chromosome-responder was normal, the increment in crossing-over was maximal in the pericentromeric region. In the case of disturbed pairing, this maximum either shifted toward the middle of the arm 2-F(2R) nondisjunction, or occupied a distal position (in females with the insertion). It is concluded that IEC pattern depends on the order of pairing in the chromosome-responder. The mechanism of IEC appears to be related to pairing "defects" within the responder. It is tempting to speculate that the onset of crossing-over is a whole-cell event, which is regulated by the overall level of chromosome pairing within the meiotic cell. Chromosomal aberrations increase the time required for attaining this level, and the start of crossing-over is delayed. As a result, (1) exchanges are observed in the regions of late synapsis, which are usually not involved in crossing-over; (2) overabundance of recombination enzymes, caused by delayed start of crossing-over, creates the conditions for decreased interference in paired regions.

Animals↗

PubMed1996

Oestradiol potentiates a prolonged progesterone-induced suppression of LH release in ovariectomised cows.

Our working hypothesis was that the negative feedback effect of progesterone on LH secretion in ovariectomised cows is greatly enhanced by oestradiol when both hormones are administered intravaginally. Each of eight ovariectomised cows had a progesterone releasing device ('CIDR-1'; Eazi-breed CIDR-B. InterAg, Hamilton, New Zealand) inserted into the vagina for 3 days, followed by an injection of 1 mg oestradiol benzoate (ODB) in peanut oil 24 h after device removal. The timing of this injection was designated as Day 0. The CIDR-1 was reinserted concurrently with an injection of 0.4 mg ODB on Day 5. An additional device ('CIDR-2') was inserted 4 days later (Day 9). In four of the cows, an ODB capsule (CIDIROL), Douglas Pharmaceuticals. Auckland, New Zealand) was placed into a groove on the surface of CIDR-2 preceding insertion. CIDR-2 was withdrawn after 5 days (Day 14) and CIDR-1 was withdrawn 2 days later (Day 16). The treatment regimen was repeated in a cross-over design where each cow received CIDR-2 with or without an ODB capsule. Blood samples were collected at intervals of 15 min for a period of 16 h beginning 8 h before insertion of CIDR-2 to determine changes in LH secretion pattern, and then at intervals of 8 h until 48 h after removal of CIDR-1 to determine mean LH and steroid concentrations. Concentrations of progesterone in plasma reflected the effects of inserting and removing each CIDR device. The insertion of CIDR-2 elevated progesterone from 2.0 +/- 0.1 ng ml-1 to 4.9 +/- 0.1 ng ml-1 within 30 min (P < 0.01) and maintained levels > 3 ng ml-1. Withdrawal of CIDR-2 produced a new baseline level of 1.8 +/- 0.1 ng ml-1 within 4 h (P < 0.01). Concentrations of oestradiol-17 beta in plasma increased from a baseline of < 1 pg ml-1 to-a-maximum of 12.6 +/- 2.2 pg ml-1 at 22 h after insertion of an ODB capsule. Initial pulse frequency of LH (1.2 +/- 0.05 pulses h-1) and mean concentration of LH (1.6 +/- 0.1 ng ml-1) declined (P < 0.05) to 0.2 +/- 0.1 pulses h-1 and 0.5 +/- 0.1 ng ml-1 during the period from 2 to 8 h following insertion of CIDR-2. Mean concentrations recovered to pre-treatment levels (> 1 ng ml-1) within 48 h if CIDR-2 was inserted without an ODB capsule. In contrast, LH levels remained less than 0.7 ng ml-1 for 5 days following this form of ODB treatment. A subsequent increase in mean LH of 1.4 +/- 0.2 ng ml-1 (P < 0.05) was inversely synchronised with the precipitous decline in progesterone of 1.2 +/- 0.1 ng ml-1, following removal of CIDR-2. The inclusion of an ODB capsule with insertion of CIDR-2 reduced concentrations of FSH from 166 +/- 17 ng ml-1 to a new baseline of 105 +/- 16 ng ml-1 within 24 h (P < 0.05). In conclusion, an acute increase in progesterone induced a transient suppression of LH lasting less than 48 h. This suppression was prolonged to 5 days by the concurrent insertion of a capsule containing 10 mg ODB. The subsequent recovery of LH was coincident with the decline in progesterone following removal of CIDR-2.

Administration, Intravaginal↗

PubMed2006

Submucous myoma induces uterine inversion.

OBJECTIVE: Inversion of the uterus is indeed a rarity for a gynecologist. The puerperal variety is associated with pregnancy, including term pregnancy and abortion. The nonpuerperal condition may be tumor-induced or idiopathic. We present a nonpuerperal uterine inversion and discuss a reasonable plan for its management. CASE REPORT: A 42-year-old, unmarried woman without sexual experience and any systemic diseases noted a mass outside of the vaginal introitus combined with massive vaginal bleeding and abdominal pain of sudden onset after taking laxative agents for colonoscopic preparation. Then she had voiding difficulty with distended bladder. A suprapubic urinary catheter was inserted and 800 mL urine was drained out. The patient received emergency tumor resection and subtotal hysterectomy. The diagnosis of uterine inversion was confirmed during operation. The postoperative course was uneventful and she was discharged without complication. CONCLUSION: Nonpuerperal inversion of the uterus is rarely encountered by gynecologists. Diagnosis of uterine inversion is often not easy and imaging studies might be helpful. Surgical treatment is the method of choice in nonpuerperal uterine inversion.

Adult↗

PubMed1994

The effects of insertions on mammalian intrachromosomal recombination.

We examined the effects of insertion mutations on intrachromosomal recombination. A series of mouse L cell lines carrying mutant herpes simplex virus thymidine kinase (tk) heteroalleles was generated; these lines differed in the nature of their insertion mutations. In direct repeat lines with different large insertions in each gene, there was a 20-fold drop in gene conversion rate and only a five-fold drop in crossover rate relative to the analogous rates in lines with small insertions in each gene. Surprisingly, in direct repeat lines carrying the same large insertion in each gene, there was a larger drop in both types of recombination. When intrachromosomal recombination between inverted repeat tk genes with different large insertions was examined, we found that the rate of gene conversion dropped five-fold relative to small insertions, while the rate of crossing over was unaffected. The differential effects on conversion and crossing over imply that gene conversion is more sensitive to insertion mutation size. Finally, the fraction of gene conversions associated with a crossover increased from 2% for inverted repeats with small insertions to 18% for inverted repeats with large insertions. One interpretation of this finding is that during intrachromosomal recombination in mouse cells long conversion tracts are more often associated with crossing over.

Animals↗

PubMed1994

Inferences on passive diaphragm mechanics from gross anatomy.

The diaphragm is a relatively thin curved structure that is categorized in mechanics as a membrane. Tension in the membrane is given by the product of muscle thickness and stress parallel to the fiber bundles. If all muscle fibers were cylindrical and extended from origin to insertion, the ratio of thickness near the chest wall (CW) to thickness near the central tendon (CT) would vary inversely with the ratio of CW to CT perimeters. In freshly excised diaphragms of 36 mongrel dogs, the ratios of the perimeters (CT/CW) in the right and left costal diaphragm were 0.63 +/- 0.04 and 0.62 +/- 0.04, respectively. The means of the ratio of thickness near CW to that near CT in the right and left costal regions were 0.96 +/- 0.07 and 0.95 +/- 0.05, respectively, consistent with a nearly constant relationship between costal diaphragm membrane tension and muscle stress in the direction of the fibers. In the crural diaphragm, the average ratio of the perimeters of the insertions on CT to CW was 1.16 +/- 0.10. The average ratio of thickness of crural CW to CT was 1.25 +/- 0.11. The discrepancy between the perimeter ratio and thickness ratio in the costal diaphragm is incompatible with the muscle consisting of uniform fibers extending from CW to CT. Our data suggest that muscle fibers are either in series with a smaller number along the smaller perimeter or that they terminate by tapering within the muscle bundle. Both arrangements are consistent with previous anatomic studies (Gordon et al. J. Morphol. 201: 131-143, 1989). Having a nonuniform number of fibers mechanically in series is compatible with uniform stress in the fibers if the membrane is sufficiently curved as in a domed structure.

Animals↗

PubMed1998

Transmission pattern of hobo transposable element in transgenic lines of Drosophila melanogaster.

This study is an attempt to trace the fate of hobo elements in the genomes of E strains of Drosophila melanogaster that have been transfected with pHFL1, a plasmid containing an autonomous hobo. Such long-term population studies (over 105 generations) could be very useful for better understanding the population and genomic dynamics of transposable elements and their pattern of insertions. Molecular analyses of hobo elements in the transfected lines were performed using Southern blots of XhoI-digested genomic DNAs. The complete element was observed in all six injected lines. In two lines we observed, at generation 100, two deleted elements, which did not correspond to Th1 and Th2. The results obtained by the in situ method show that the number of hybridization sites increases in each line and prove that the hobo element may be amplified in an RM genome. The hobo activity does not seem to be systematically correlated with the number of hobo elements. After generation 85, the evolution of the hobo element's insertion site number depends on the injected line. In all lines, the total number of insertions remains quite small, between 0 and 11. Hobo elements are located on each of the chromosomal arms. We describe 'hotspots'-insertion sites present in all lines and in all generations. On the 3R arm, a short inversion appeared once at generation 85.

Animals↗

PubMed1990

The transposable element Uhu from Hawaiian Drosophila--member of the widely dispersed class of Tc1-like transposons.

We report the complete nucleotide sequence of the transposable element Uhu from the vicinity of the alcohol dehydrogenase (Adh) gene of Drosophila heteroneura (an endemic Hawaiian Drosophila). The complete element is about 1650 base-pairs (bp) long, has 46-50 base-pair inverse imperfect repeats at it's ends, and contains a large open reading frame potentially encoding a 192 amino acid protein. We demonstrate that Uhu belongs to a class of transposable elements which includes Tc1 from Caenorhabditis elegans, Barney from Caenorhabditis briggsae, and HB1 from Drosophila melanogaster. All of these elements share significant sequence similarity, are approximately 1600 base pairs long, have short inverse terminal repeats (ITRs), contain open reading frames (ORFs) with significant sequence identity, and appear to insert specifically at TA sequences generating target site duplications.

Alcohol Dehydrogenase↗

PubMed1999

Excrescent lesion: a diagnosis of lateral talar exostosis in chronically symptomatic sprained ankles.

The excrescent lesion is a symptomatic anterolateral exostosis at the insertion of the anterior talofibular ligament. It is found in patients with chronic ankle pain after inversion injuries. It is most reliably diagnosed by computed tomography scan, but physical examination and oblique radiographs are suggestive in most cases. A technique for surgical excision and, in some cases, repair of the anterior talofibular ligament is described. Five patients having a history of inversion sprains of the ankle, without significant symptomatic improvement for a mean of 21 months after the injury, were evaluated. None had significant instability in the ankle or subtalar joints, clinically or with stress radiographs. The diagnosis of excrescent lesion was confirmed with computed tomography scan in all five patients. Each underwent excision of the exostosis. Removal of the exostosis produced laxity of the anterior talofibular ligament in four of the patients and required an additional modified Broström procedure to tighten the anterior talofibular ligament. Clinical results were evaluated at a mean of 33 months postoperatively, using the Ankle-Hindfoot scale from the American Orthopaedic Foot and Ankle Society. The three patients without pending claims for Workers' Compensation or related litigation all had excellent results (mean score, 93 points). Two patients with active legal claims had fair and poor results (mean score, 53 points).

Adult↗

PubMed1998

[Measurement of expired nitric oxide concentration].

UNLABELLED: Much interest has been focused on standardization of measurement of expired nitric oxide (NO) concentration. The aim of this study was establish a simple measurement of expired NO concentration. SUBJECTS AND METHODS: This study included 5 healthy male adults. To clarify whether NO is excreted in expired air constantly, its concentrations were measured while changing the flow rate. To examine the influence of NO derived from the nasal cavity, we compared expired No concentrations sampled from the month with those sampled from the endotracheal tube inserted to the trachea at a constant flow rate serially. RESULTS: Expired NO concentrations decreased in inverse with the flow rate. No may be serially excreted in expired air. When serial changes of expired No concentrations sampled from the mouth were examined, its NO concentration initially reached a peak, then showed a plateau. Serial changes of those sampled from the endotracheal tube showed only a plateau. Plateau levels were not different between the two kinds. Therefore the peak values may have been influenced by NO derived from the nose that fell in the trachea by inspiration. Plateau values appeared to represent airway and lung-derived NO. CONCLUSIONS: A simple measurement of expired NO concentration should be sampled from the mouth at a constant flow rate serially. Evaluating plateau values is appropriate for expired NO concentration.

Adult↗

PubMedDate not supplied

Effects of drill speed on heat production and the rate and quality of bone formation in dental implant osteotomies. Part I: Relationship between drill speed and heat production.

The amount of heat produced by dental implant osteotomy (receptor site) preparation at different speeds and the effects of heat production on the prognosis of implant treatment are controversial. In Part I of this two-part study, heat production was measured in vivo during osteotomy preparation at low (maximum 2,000 rpm), intermediate (maximum 30,000 rpm), and high (maximum 400,000 rpm) speeds in the rabbit tibia, and an inverse relationship was observed between drill speed and heat production. For the measurement of heat production (Part I), a thermocouple probe was inserted into a prepared receptor site in the anteromedial aspect of the tibial metaphysis. Temperature was recorded while an osteotomy was drilled 1 mm from the thermocouple receptor site. Distilled water was used as coolant in conjunction with all drilling, and all osteotomies were prepared by a single researcher to eliminate the variable of interoperator difference in technique. An inverse relationship was observed between drill speed and heat production. An analysis of variance indicated significant differences in heat production among the three drilling speeds (P < 0.05). The results of Part 1 of this study indicate that for the configuration and material of bur used, the high-speed range minimizes heat production.

Analysis of Variance↗

PubMed2006

Monitoring of cochlear function during cochlear implantation.

OBJECTIVE: To report the feasibility of monitoring cochlear function during cochlear implantation. STUDY DESIGN: Case report. SETTING: Tertiary care referral center. METHODS: A child with audiologic features typical of bilateral auditory neuropathy underwent cochlear implantation. The scala tympani was entered inferior and slightly anterior to the round window membrane margin and smooth electrode insertion was achieved. Using single polarity click stimuli, the cochlear microphonic was measured at several steps during surgery. RESULTS: Cochlear microphonics were present at all stages during the implantation process and were clearly distinguished from neural responses by stimulus polarity inversion and constant latencies, despite changes in stimulus level. With the electrode in situ, amplitudes were smaller but persisted until the final measurement at 10 minutes after insertion. At follow-up 2 weeks after surgery, behavioral audiometry results indicated profound hearing loss in the operated ear. CONCLUSIONS: This paper demonstrates the feasibility of monitoring cochlear function during cochlear implantation. The routine surgical approach did not appear to adversely affect the functional measurements. Standard size, full electrode insertion did diminish the amplitude of the cochlear microphonics, possibly as a result of intracochlear mechanical impairment. Ultimately, profound hearing loss was documented, indicating that factors other than immediate changes induced by electrode insertion were likely responsible for the loss of cochlear function.

Cochlear Implantation↗

PubMed1996

Inversion of the membrane topology of SecG coupled with SecA-dependent preprotein translocation.

E. coli preprotein translocase comprises SecA and SecY/E/G complex. SecA delivers the preprotein to the putative protein-conducting channel formed by SecY/E by undergoing ATP-driven cycles of membrane insertion and deinsertion. SecG renders the translocase highly efficient. An antibody raised against the C-terminal region of SecG inhibits preprotein translocation into everted membrane vesicles despite the exposure of this region to the inside of membrane vesicles in the absence of preprotein translocation. When preprotein translocation was started with ATP and then blocked by the inhibition of ATP hydrolysis, the C-terminal region was exposed to the outside of membrane vesicles. Another region of SecG showed a change in membrane sidedness upon preprotein translocation, indicating that SecG undergoes topology inversion. This topology inversion was tightly coupled to the SecG function and linked with the insertion-deinsertion cycle of SecA.

Adenosine Triphosphatases↗

PubMed1998

Major chromosomal rearrangements induced by T-DNA transformation in Arabidopsis.

We show that major chromosomal rearrangements can occur upon T-DNA transformation of Arabidopsis thaliana. In the ACL4 line, two T-DNA insertion loci were found; one is a tandem T-DNA insert in a head-to-head orientation, and the other is a truncated insert with only the left part of the T-region. The four flanking DNA regions were isolated and located on the Arabidopsis chromosomes; for both inserts, one side of the T-DNA maps to chromosome 2, whereas the other side maps to chromosome 3. Both chromosome 3 flanking regions map to the same location, despite a 1.4-kb deletion at this point, whereas chromosome 2 flanking regions are located 40 cM apart on the bottom arm of chromosome 2. These results strongly suggest a reciprocal translocation between chromosomes 2 and 3, with the breakpoints located at the T-DNA insertion sites. The interchanged fragments roughly correspond to the 20-cM distal ends of both chromosomes. Moreover, a large inversion, spanning 40 cM on the genetic map, occurs on the bottom arm of chromosome 2. This was confirmed by genetic analyses that demonstrated a strong reduction of recombination in the inverted region. Models for T-DNA integration and the consequences for T-DNA tagging are discussed in light of these results.

Arabidopsis↗

PubMed2004

Mapping Ds insertions in barley using a sequence-based approach.

A transposon tagging system, based upon maize Ac/Ds elements, was developed in barley (Hordeum vulgaresubsp. vulgare). The long-term objective of this project is to identify a set of lines with Ds insertions dispersed throughout the genome as a comprehensive tool for gene discovery and reverse genetics. AcTPase and Ds-bar elements were introduced into immature embryos of Golden Promise by biolistic transformation. Subsequent transposition and segregation of Ds away from AcTPase and the original site of integration resulted in new lines, each containing a stabilized Ds element in a new location. The sequence of the genomic DNA flanking the Ds elements was obtained by inverse PCR and TAIL-PCR. Using a sequence-based mapping strategy, we determined the genome locations of the Ds insertions in 19 independent lines using primarily restriction digest-based assays of PCR-amplified single nucleotide polymorphisms and PCR-based assays of insertions or deletions. The principal strategy was to identify and map sequence polymorphisms in the regions corresponding to the flanking DNA using the Oregon Wolfe Barley mapping population. The mapping results obtained by the sequence-based approach were confirmed by RFLP analyses in four of the lines. In addition, cloned DNA sequences corresponding to the flanking DNA were used to assign map locations to Morex-derived genomic BAC library inserts, thus integrating genetic and physical maps of barley. BLAST search results indicate that the majority of the transposed Ds elements are found within predicted or known coding sequences. Transposon tagging in barley using Ac/Ds thus promises to provide a useful tool for studies on the functional genomics of the Triticeae.

Base Sequence↗

PubMed1980

Further physical characterization of deletion and substitution mutants affecting the control of lysogeny in bacteriophage P2.

A deletion of phage P2, del6 (L.E. Bertani, 1980), thought to remove the structural gene int, and a deletion/substitution, vir94, thought to remove genes int, C and cox, were mapped by electron microscopy, using the heteroduplex technique. Four independent deletion/substitution mutations, all affecting the regulatory region of P2, were compared in all possible combinations with the same technique: two showed sequence homology in their substitution DNA. The results confirm the model proposed for the origin of these mutants, analogous to that for the origin of transducing variants in phage lambda, but suggest in first approximation that the exchange between the P2 DNA and the chromosome of the host bacterium may occur at several different bacterial sites. A map of the regulatory region of P2, based on all data available from the study of deletions and insertions, is presented.

Chromosome Deletion↗