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PubMed2006

[A method using long primers for cloning the upstream sequence of delta-6 fatty acid desaturases gene of Thamnidium elegans by nested inverse PCR].

Thamnidium elegans is a kind of phycomycete that produces essential unsaturated fatty acids, particularly y-linolenic acid. In this process, delta6-Fatty acid desaturase (D6D) plays a key role due to its enzymatic properties that catalyze the delta6 site dehydrogenation of precursor linoleic acid (18:2delta(9, 12) n-6) and a-linolenic acid (18:3delta(9, 12, 15) n-3). This reaction is the first and rate-limiting step of highly unsaturated fatty acids (HUFA) synthesis pathways. After we have isolated and cloned the gene coding delta6-fatty acid desaturase from Thamnidium elegans As3.2806 (GenBank accession number DQ099380), our interest focuses on the promotion and regulation of the gene transcription. To achieve this aim, we designed long primers and used nested inverse PCR to amplify DNA flanking sequences. First, genome of Thamnidium elegans was extracted and digested with restriction enzymes EcoR I and Kpn I , respectively. Then we ligated the digested DNA with T4 ligase at low concentration which is propitious for linear DNA to joint intromolecule. According to the sequence of delta6-fatty acid desaturase gene of Thamnidium elegans, we designed a couple of 35nt long inverse primers and two couples of shorter inverse primers for inverse PCR. Three rounds of PCR reactions were performed. In the primary reaction, the ligated DNA was used as a template, and the product was used as the template of the secondary reaction, the tertiary reaction was achieved in the same way. After all the three rounds of reactions, we got a nice product about 4 kb from the EcoR I digested sample, in which a 1.3kb 5' upstream sequence (GenBank accession number DQ309425) of delta6-fatty acid desaturase gene containing several putative regulatory elements including TATA. box, FSE-2, AP-1 sites, CCAAT cis-element site and STRE-binding site was derived after sequencing. All of these implied intensely that this 1.3kb fragment is a condition-regulated promoter. It is the first report about Thamnidium elegans detla6-fatty acid desaturase gene promoter. The procedure described here is a rapid and simple method and particularly useful to isolate flanking sequences from fungal genome. box, FSE-2, AP-1 sites, CCAAT cis-element site and STRE-binding site was derived after sequencing. All of these implied intensely that this 1.3 kb fragment is a condition-regulated promoter. It is the first report about Thamnidium elegans delta6-fatty acid desaturase gene promoter. The procedure described here is a rapid and simple method and particularly useful to isolate flanking sequences from fungal genome.

Base Sequence↗

PubMed2006

Inversion appendicectomy.

OBJECTIVES: (i) To emphasise that incidental appendicectomy has indications and, to highlight this indications. (ii) To teach that, even when indicated, this procedure should not convert a clean surgical wound into a clean contaminated or even less optimal wound. (iii) To recommend that if an incidental appendicectomy is to achieve (ii) above, inversion appendicectomy is the better option to choose. (iv) To prove that inversion appendicectomy is fast, easy and achieves a similar result as the more popular excision appendicectomy. PATIENTS AND METHODS: This study was carried out in the paediatric surgical unit of Korle-Bu Teaching Hospital Accra, Ghana - between March 2003 and May 2004. PATIENT SELECTION: Fifteen patients qualified for enrollment into this study. These were (i) Those who had clear cut indications for incidental appendicectomy, and had it done as an inversion appendicectomy. (ii) Cases of incidental appendicectomy. METHODS: Eleven of these cases were done for intussusceptions and four for malrotation. Only wounds that qualified as clean surgical wounds were included in this study. There was no age or sex discrimination. RESULTS: Follow up on these patients did not reveal any complications. CONCLUSION: Incidental appemdicectomy has well-defined indications. When indicated in clean wound, inversion appendicectomy is the procedure of choice.

Appendectomy↗

PubMedDate not supplied

Studies on the metabolism and chiral inversion of ibuprofen in isolated rat hepatocytes.

The oxidative metabolism and chiral inversion of ibuprofen in freshly isolated rat hepatocytes was studied with the aid of a stereoselective GC/MS assay procedure. Hydroxylation of the isobutyl side chain at the subterminal carbon (to give hydroxyibuprofen) proved to be the major route of metabolism of both R(-)-ibuprofen and S(+)-ibuprofen, while formation of the corresponding diastereoisomeric 2-methylpropionic acid derivatives (carboxyibuprofen) was of minor quantitative importance. Both oxidative pathways were inhibited in the presence of metyrapone, a cytochrome P-450 inhibitor. R(-)-Ibuprofen underwent metabolic chiral inversion to the S(+) enantiomer, whose formation was dependent on incubation time, cell density, and substrate concentration. S(+)-Ibuprofen, on the other hand, was not converted to R(-)-ibuprofen in rat hepatocytes. When cells were incubated with a mixture of unlabeled R(-)-ibuprofen and R(-)-[3,3,3-2H3]ibuprofen, the resultant S(+) enantiomer consisted only of unlabeled and trideutero molecules (formed in the same ratio as the corresponding species of R(-)-ibuprofen), indicating that 2,3-dehydroibuprofen did not serve as the symmetrical intermediate in the chiral inversion reaction. Collectively, these results demonstrate that freshly isolated rat hepatocytes represent a convenient and reproducible in vitro model system for studies on the metabolism and chiral inversion of ibuprofen.

Animals↗

PubMed1989

Acute puerperal uterine inversion. New approaches to management.

A retrospective review identified 56 patients with uterine inversion, from July 1977 through June 1986, from weekly obstetric statistics, delivery records and computerized discharge diagnoses. All patients underwent delivery by house officers, midwives or medical students under supervision. An analysis of the data revealed that the risk factors were primiparity, a fundally implanted placenta and delivery of a macrosomic fetus. Also, patients who received oxytocin with or without MgSO4 were at higher risk of puerperal inversion. MgSO4 by itself did not appear to be a risk factor. A placenta attached at the time of inversion appeared to have a protective effect against the development of shock. The use of betamimetics or MgSO4 appeared to be an acceptable alternative to general anesthesia in relaxing the uterus and aiding in its repositioning. Those agents were more likely to be successful in acute cases than in subacute ones and in second-degree inversion than in third-degree.

Adolescent↗

PubMed1985

Supraspinal convulsions induced by inverse benzodiazepine agonists in rabbits.

The electroencephalographic (EEG) effects of inverse benzodiazepine (BDZ) agonists have been studied in rabbits after i.v. administration. A dose-dependent progression of three different stages of EEG changes have been observed with inverse BDZ agonists. At first, trains of slow waves in the occipital cortex occur, followed by trains of spike-and-wave complexes in the sensorimotor cortex. These two stages are superimposed on a desynchronized cortical activity, accompanied by an enhancement of the hippocampal theta rhythm. These EEG changes parallel a state of alertness. The third stage is characterized by generalized grand-mal seizures made up of high voltage spikes in the cortical and subcortical brain areas accompanied by generalized tonico-clonic convulsions. No modification of electrical activity is observed at the level of the spinal cord. Methyl-beta-carboline-3-carboxylate (beta-CCM) (at doses higher than 0.2 mg/kg) and 6,7-dimethoxy-4-ethyl-beta-carboline-3-carboxylate (DMCM) (at doses higher than 0.4 mg/kg) elicit all three stages, whereas ethyl-beta-carboline-3-carboxylate (beta-CCE) (0.2-2 mg/kg) and N-methyl-beta-carboline-3-carboxamide (2-20 mg/kg) only elicit the first two, and finally CGS 8216 only the first. The extent of the EEG progression by inverse BDZ agonists may therefore be used as an index of the efficacy of each compound. The BDZ antagonists Ro 15-1788 and Ro 15-3505 (0.3 mg/kg or higher), which do not change the EEG pattern, block the effects of the convulsant and subconvulsant doses of the inverse BDZ agonists, giving rise to a desynchronized EEG pattern.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

PubMed1987

Regulation of basal and insulin-stimulated glycogen synthesis in cultured hepatocytes. Inverse relationship to glycogen content.

Cultured rat hepatocytes were used to characterize the relationship between cellular glycogen content and the basal rate, as well as response to insulin of glycogen synthesis. Depending on the concentration of medium glucose, glycogen-depleted monolayers accumulated glycogen between 24 and 48 h of culture up to the fed in vivo level. Insulin at 100 nM stimulated glycogen deposition 20-fold at 1 mM and 1.5-fold at 50 mM glucose. The rate of further glycogen storage decreased with time and increasing glycogen content. In hepatocytes preincubated with 1-50 mM glucose during 24-48 h, short-term basal and insulin-dependent incorporation of 10 mM [14C]glucose into glycogen was inversely related to the actual cellular glycogen content. This was not due to different intracellular dilution of the label, since the specific radioactivity of UDP-glucose was similar in all groups. 125I-Insulin binding indicated that insulin receptors were also not involved in this phenomenon. An inverse relationship was also found between glycogen content and the stimulation of glycogen synthase I activity by insulin, whereas the basal activity of the enzyme was dissociated from the rate of incorporation of [14C]glucose. Basal net glycogen deposition at 10 mM glucose was also inversely related to cellular glycogen; however, no such relation was evident in the presence of insulin due to the overlapping inhibition of glycogenolysis. These studies suggest that the glycogen-mediated inhibition of the activation of glycogen synthase I is operative in the cultured hepatocyte and leads to an apparent inverse relationship between the actual glycogen content and basal as well as insulin-dependent glycogenesis.

Animals↗

PubMedDate not supplied

Inversion lateral ankle trauma: differential diagnosis, review of the literature, and prospective study.

This study is comprised of 71 patients with inversion injuries. The purpose of this article is to present a logical and orderly approach in evaluating these injuries. A comprehensive review of the literature concerning diagnostic techniques and mechanisms of injury related to inversion ankle trauma is presented. Inversion ankle injuries are frequently misdiagnosed as simple sprains when frequently there are other pathologies present. The standard approach of evaluating inversion ankle injuries is often inadequate.

Ankle Injuries↗

PubMedDate not supplied

Ocular manifestations of gravity inversion.

To determine the ocular manifestations of inverting the human body into a head-down vertical position, we evaluated normal volunteers with applanation tonometry, fundus photography, fluorescein angiography, and ophthalmodynamometry. Compared with data obtained in the sitting position, the intraocular pressure more than doubled on inversion (35.6 +/- 4 v 14.1 +/- 2.8 mm Hg, n = 16), increasing to levels well within the glaucomatous range. Pressures in the central retinal artery underwent similar increases, while the caliber of the retinal arterioles decreased substantially. External ocular findings associated with gravity inversion included orbital congestion, conjunctival hyperemia, petechiae of the eyelids, excessive tearing (epiphora), and subconjunctival hemorrhage. We suggest that patients with retinal vascular abnormalities, macular degeneration, ocular hypertension, glaucoma, and similar disorders refrain from inversion altogether. Whether normal individuals will suffer irreversible damage from inversion is uncertain, but it seems prudent to recommend that prolonged periods of inverted posturing be avoided.

Adult↗

PubMed1982

[Genetic determinism of the female sex inversion accompanying the crossing of two subspecies of Idotea balthica (Pallas). I.--Results on albafusca, bilineata and uniformis phenotypes].

A reversal of sexual phenotype resulting in the appearance of neo-males and neo-females occurs in the populations of two marine subspecies of Idotea balthica. Sex inversions are rare in I. b. basteri but more frequent in I. b. tricuspidata. By crossing these two subspecies, the rate of neo-males (ti) was considerably increased, allowing us to study the determination of sex inversion. The I. b. tricuspidata used in this study came from the offspring (27 p. 100 neo-males) of one gravid albafusca female (A1) collected in La Rochelle (LR); these offspring had been studied for five generations. The I. b. basteri came from offspring of females collected in Marseille (M), Racou (eastern Pyrenees) and Tunis. The chi 2 or Mann-Whitney test was used to compare the results of the different crosses. The female Idotea balthica is heterogametic (WZ); the male is homogametic (ZZ). The loci of the genes which determine the colored phenotypes, albafusca (A) and bilineata (B), are situated on the W heterochromosome. The fundamental phenotype, uniformis (U), is the wild type, according to classical genetics. The males used were either ZZ and uniformis or WZ (neo-males) and albafusca. 1) Ten crosses: female A basteri (M) X male U tricuspidata (LR) gave a variety of offsprings (chi 2 = 56 - d.f. = 9), two having an A1-like ti and the other eight no or very few neo-males. 2) Backcrosses (from CRF2 to CRF5) between hybrid females and U La Rochelle males: in CRF2, the ti increased significantly and in CRF3, CRF4 and CRF5 it reached the ti of the A1 lineage. 3) In the female F1 X male UM backcrosses, the ti was nearly zero, thus being comparable with the basteri lineage of Marseille. 4) When female ALR X male UM of some lineages was crossed, the expressivity of the phenotype A was reduced (from A to U) only in neo-males. The penetrance of gene A did not vary significantly in seven crosses from F1 to CRF2. 5) The crossing of male male ULR with female female basteri B or U from various populations showed that only some B and U females were likely to favor sex inversion in their daughters; the resulting ti was ten times higher with A females. These results led to the following conclusions: --crosses 1, 2 and 3 showed that reinforcement of the tricuspidata genotype of La Rochelle, by means of a regular addition of mainly autosomal genes, induced an increase in the ti, whereas reinforcement of the basteri genotype induced a decrease in that rate. The results supported the hypothesis of a polyfactorial determination of sex involving autosomal, or partly sex-linked, factors acting as inhibitors of the major female gene(s); --crosses 4 showed that the reduction of gene A expressivity was always associated with the sex inversion of genetic hybrid females; that process also seemed to be controlled by some autosomal or partly sex-linked recessive genes, different from those of the preceding complex and acting as inhibitors of the major female-determining factor(s) situated on the W heterochromosome...

Animals↗

PubMed1981

[Effect of light schedule inversion on mitotic cycle parameters in the esophageal epithelium of mice].

Parameters of the cell mitotic cycle (MC) in the esophageal epithelium of mice were studied 5, 10 and 17 days after inverting the light schedule (light from 8 a. m. to 8 p. m. in the control group, L : D = 12:12, and light from 8 p. m. to 8 a. m. in the experimental one., L : D = 12:12). The duration of different MC periods is similar in the control and experimental animals at varying time after inversion of the light schedule: G2min- 1.0-2.0 h, G2 + 1/2M = 2.0 -2.7 h, S = 7.1-7.7 h, G1 + 1/2M = 14.0-15.5 h. The total MC duration is 24-25 h. The pattern of the labeled mitotic curves after inversion only slightly differs from the control. This is evidence of stability of MC cell kinetics after inversion of the light schedule. The intracyclic regulatory mechanisms appear not to be affected essentially by this inversion.

Animals↗

PubMed1980

In vivo D-ethionine inversion and its inhibition.

The quantitative study of the inversion of D-ethionine into L-ethionine in vivo, measured in the liver of rats by the formation of S-adenosylethionine from L-ethionine, demonstrates high efficiency of this conversion when lower doses of D-ethionine are used. At higher doses (> 25 mg (80 mumol)/100 g body wt) the accumulation of S-adenosylethionine is retarded. It is suggested that this decrease of S-adenosylethionine formation is due to an unknown as yet effect of D-ethionine on the L-ethionine metabolism. At these higher doses, the alternative assay of the inversion, based on determining the dilution of radioactive L-ethionine probes by inverted D-ethionine, demonstrates considerably higher inversion, supporting the previous assumption. The inversion can be inhibited by administering D-ethionine simultaneously with either kojic acid or sodium benzoate, both inhibitors of D-amino acid oxidase. Sodium benzoate administration is tolerated very well by rats and therefore may be used in chronic experiments.

Animals↗

PubMed1995

Puerperal inversion of one horn of a bicornuate uterus. A case report.

BACKGROUND: Acute uterine inversion is a rare (1:2,500-25,000 deliveries) but potentially life-threatening obstetric complication. Uterine malformation can make it difficult to diagnose and treat this emergency. CASE: Following a normal delivery in a nullipara, laparotomy was required to establish the diagnosis and treat an inversion of one horn of a bicornuate uterus. CONCLUSION: Inversion of one horn of a bicornuate uterus presents a diagnostic dilemma. When physical examination reveals a palpable abdominal "fundus" and a mass protruding through the cervix in a patient who is experiencing uterine hemorrhage, the cause may be inversion of one horn of a bicornuate uterus. Laparotomy may be required for definitive diagnosis and treatment.

Adult↗

PubMed1995

Emergent obstetric management of uterine inversion.

Puerperal inversion of the uterus is an unusual and potentially life-threatening event occurring in the third stage of labor, but when managed promptly and aggressively inversion can result in minimal maternal morbidity and mortality. Once the diagnosis of inversion is made, measures should be undertaken to manage and correct acute blood loss and potential shock. In conjunction with anesthesia personnel, immediate uterine replacement should be considered. Uterine relaxants (MgSO4, terbutaline, or halothane) can be used if initial attempts fail; however, in the majority of patients successful immediate replacement without use of uterine relaxants is possible. The choice of anesthetic agent and uterine relaxants should be individualized based on the clinical scenario. Following manual replacement, massage and ecbolic agent(s) should be instituted immediately to prevent reinversion. Surgical repositioning via an abdominal or vaginal approach may be necessary in subacute or chronic inversions.

Anesthesia, Obstetrical↗

PubMedDate not supplied

Different clinical implications for ST depression and T wave inversion in non-Q wave myocardial infarction.

The differences between ST depression and T wave inversion in non-Q wave myocardial infarction were investigated in 42 patients with initial non-Q wave infarction, 22 patients with ST depression (ST group), and 20 patients with T wave inversion (T group). The extent of ischemic area estimated by electrocardiography and two-dimensional echocardiography, characteristic features of electrocardiographic changes, and clinical findings on admission and outcome were estimated. ST elevation preceded T wave inversion in the same leads in 80% (16/20) of the T group, and transient Q waves developed in 55% (11/20). However, neither ST elevation nor transient Q waves were observed in the ST group. Two or three ischemic segments were present in 86% (19/22) of the ST group patients, but only one ischemic segment was present in 60% (12/20) of T group patients, predominantly the anterior segment. The short-axis view of the two-dimensional echocardiogram on the level of papillary muscle showed decreased contraction in two or three of the anterior, lateral, and inferior segments of the left ventricle in 78% (14/18) of ST group patients. Only one segment with decreased contraction was present in 100% (17/17) of T group patients. Cardiac status on admission was lower in the ST than the T group: Killip class II-IV, 59% (13/22) vs 20% (4/20), p < 0.05; mortality rate after 1 month, 41% (9/22) vs 0% (0/20), p < 0.05. Coronary angiograms, left ventriculograms, and autopsy findings also showed extensive myocardial lesions in accordance with multivessel disease in the ST group, but localized myocardial lesion suggesting one-vessel territory in the T group. T wave inversion in non-Q wave myocardial infarction indicates a recovery phase in transient transmural ischemia and localized subendocardial infarction within the presumed one-vessel territory, while ST depression suggests the presence of extensive ischemia in the subendocardium of multivessel territory, and infarction within that region.

Aged↗

PubMed1993

Virtual trajectory and stiffness ellipse during multijoint arm movement predicted by neural inverse models.

We predict the virtual trajectories and stiffness ellipses during multijoint arm movements by computer simulations. A two-link manipulator with four single-joint muscles and two double-joint muscles is used as a model of the human arm. Physical parameters of the model are derived from several experimental data. Among them, special emphasis is put on low values of the dynamic hand stiffness recently measured during single-joint and multijoint movements. The feedback-error-learning scheme to acquire the inverse dynamics model and the inverse statics model is utilized for this prediction. The virtual trajectories are much more complex than the actual trajectories. This indicates that planning the virtual trajectory is as difficult as solving the inverse dynamics problem for medium and fast movements, and simply falsifies the advocated computational advantage of the virtual trajectory control hypothesis. Thus, we conclude that learning inverse models is essential even in the virtual trajectory control framework. Finally, we propose a new computational model to learn the complicated shape of the virtual trajectories by integrating the virtual trajectory control and the feedback-error-learning scheme.

Arm↗

PubMed1993

Selection of an active single chain Fv antibody from a protein linker library prepared by enzymatic inverse PCR.

Enzymatic inverse PCR mutagenesis was developed as a simple and reliable method for the construction of large libraries of site-directed mutants. Enzymatic inverse PCR library mutagenesis uses a single PCR fragment and is restriction-site independent. The usefulness of the technique was demonstrated by the design of a single chain linker for an antibody Fv fragment without computer modeling. The Fv fragment of an antibody specific for a metal chelate was expressed in active form in the periplasm of E. coli. The light and the heavy chains of the Fv are expressed as a bicistronic mRNA. Enzymatic inverse PCR mutagenesis was used to construct a library of 3 x 10(5) Fv mutants, in which the C-terminus of the light chain was connected to the N-terminus of the heavy chain by a 15-amino acid peptide linker of variable composition. After plating, active mutant colonies were identified by screening colony filter lifts with a radiolabeled hapten, N'-(2-hydroxyethyl)-p-thioureidobenzyl EDTA. About 0.2% of the mutants were positive, and a selected sFv clone was shown to have the same affinity as the Fv (9 x 10(9)) and was similar to the whole antibody (11 x 10(9)). This example compares favorably with both of the other approaches to constructing sFv's; namely, molecularly modeled linkers as well as universal linkers, which have often yielded significantly lower affinities than whole antibodies or Fabs. The enzymatic inverse PCR library mutagenesis approach is simple and reliable and can be used to obtain linkers for the great majority of antibodies for which no structural data are available. More generally, it can be used to modify DNA coding for any structural protein or regulatory element.

Base Sequence↗

PubMed1988

Escherichia coli host factor for site-specific DNA inversion: cloning and characterization of the fis gene.

The Escherichia coli (Es. coli) protein Fis (factor for inversion stimulation) stimulates site-specific DNA inversion of the G segment in phage Mu by binding to a recombinational enhancer. By using synthetic oligonucleotides deduced from the amino-terminal amino acid sequence, we have cloned the gene (termed fis) encoding this specific DNA-binding protein. The DNA sequence shows that the Fis protein is basic and contains 98 amino acids. A helix-turn-helix sequence motif characteristic of many DNA-binding proteins is located at the carboxyl-terminal end of the protein. By marker exchange, we have constructed an insertion mutation of fis. Fis is nonessential for Es. coli growth; however, inversion of the G segment of a Mu prophage was not detected in the fis mutant. The fis gene is located between 71 and 72 min on the Es. coli genetic map.

Amino Acid Sequence↗

PubMed2000

Case of partial duplication 2q3 with characteristic phenotype: rare occurrence of an unbalanced offspring resulting from a parental pericentric inversion.

We report on a male infant with partial trisomy 2q (q34-->qter) resulting from a maternal pericentric inversion of chromosome 2 (p25. 2q34). The infant had clinical findings similar to the characteristic phenotype associated with a partial duplication of chromosome 2q3. Carriers of pericentric inversions of chromosome 2 have an increased risk of pregnancy loss but have only rarely been reported to have a liveborn offspring with an unbalanced chromosome constitution. This case further confirms the risks associated with a pericentric inversion of chromosome 2 and is the second report with manifestations of the trisomy 2q3 phenotype.

Adult↗