Do genetic factors influence the Dejours phenomenon?
Explore the source record for details and available documents.
Animals↗
Biomedical subjects
F Han
Publications and source records attributed to F Han.
Incorporating inheritance into models for understanding ventilatory behavior.
Ventilation and its components (frequency and tidal volume) appear to be determined to a significant extent by inheritance. Gene manipulation, gene identification, and functional genomics now offer powerful tools to identify the strength and mode of inheritance for ventilatory behavior under steady-state and non-steady-state conditions, in health and in disease. Conscious integration of genetic principles into existing explanatory models may increase the likelihood of detecting traits that correlate with protein systems responsible for the structures and the functional components of respiration.
Humans↗
Ventilatory behavior after hypoxia in C57BL/6J and A/J mice.
Given the environmental forcing by extremes in hypoxia-reoxygenation, there might be no genetic effect on posthypoxic short-term potentiation of ventilation. Minute ventilation (VE), respiratory frequency (f), tidal volume (VT), and the airway resistance during chemical loading were assessed in unanesthetized unrestrained C57BL/6J (B6) and A/J mice using whole body plethysmography. Static pressure-volume curves were also performed. In 12 males for each strain, after 5 min of 8% O2 exposure, B6 mice had a prominent decrease in VE on reoxygenation with either air (-11%) or 100% O2 (-20%), due to the decline of f. In contrast, A/J animals had no ventilatory undershoot or f decline. After 5 min of 3% CO2-10% O2 exposure, B6 exhibited significant decrease in VE (-28.4 vs. -38.7%, air vs. 100% O2) and f (-13.8 vs. -22.3%, air vs. 100% O2) during reoxygenation with both air and 100% O2; however, A/J mice showed significant increase in VE (+116%) and f (+62.2%) during air reoxygenation and significant increase in VE (+68.2%) during 100% O2 reoxygenation. There were no strain differences in dynamic airway resistance during gas challenges or in steady-state total respiratory compliance measured postmortem. Strain differences in ventilatory responses to reoxygenation indicate that genetic mechanisms strongly influence posthypoxic ventilatory behavior.
Airway Resistance↗
Treatment effects on carbon dioxide retention in patients with obstructive sleep apnea-hypopnea syndrome.
OBJECTIVES: This study was designed to examine respiratory control in patients with obstructive sleep apnea-hypopnea syndrome (OSAHS), with or without CO(2) retention. METHODS: We recruited 10 body mass index-matched, apnea-hypopnea index-matched, age-matched, and lung function-matched OSAHS patients, according to their awake PaCO(2). Five patients were hypercapnic (PaCO(2), > or = 45 mm Hg), and five patients were eucapnic. Hypoxic responses (the ratio of the change in minute ventilation [DeltaV(E)] to the change in arterial oxygen saturation [DeltaSaO(2)] and the ratio of the change in mouth occlusion pressure over the first 100 ms of inspiration against an occluded airway [DeltaP(0.1)] to DeltaSaO(2)) and hypercapnic responses (DeltaV(E)/DeltaPCO(2) ratio and DeltaP(0.1)/DeltaPCO(2) ratio) were tested during wakefulness before treatment in all 10 patients, and before and during treatment (at 2, 4, and 6 weeks) with pressure support in the hypercapnic group. RESULTS: Hypercapnic patients had lower mean (+/- SD) DeltaV(E)/DeltaSaO(2) ratio than eucapnic patients (-0.17 +/- 0.04 vs -0.34 +/- 0.04 L /min/%SaO(2), respectively), lower mean DeltaP(0.1)/DeltaSaO(2) ratio (-0.04 +/- 0.02 vs -0.14 +/- 0.03 cm H(2)O/%SaO(2), respectively), and lower DeltaP(0.1)/DeltaPCO(2) ratio (0.23 +/- 0.1 vs 0.49 +/- 0.1 cm H(2)O/mm Hg, respectively) [p < 0.05]. After receiving noninvasive ventilation treatment, the hypercapnic and hypoxic responses of the hypercapnic patients increased. At 4 to 6 weeks, values for both responses had increased to within the normal range and PaCO(2) had fallen to < 45 mm Hg, while weight was unchanged. CONCLUSIONS: Depressed chemoresponsiveness plays a role that is independent of obesity in the development of CO(2) retention in some OSAHS patients, and it may be a response to sleep-disordered breathing.
Adult↗
[Generation of human recombinant antibody Fab fragment to influenza virus from combined antibody library].
OBJECTIVE: To acquire the recombinant human monoclonal antibodies to influenza virus which can be used in mucous membrane treatment to prevent the infection of virus in animal model in the future. METHODS: Construct and pan human Fab antibody library to influenza virus Sydney strain (H3N2) from vaccinated donors by using phage display technology and secreted expression in E. Coli system. The positive Fab clones with neutralization activity to influenza virus were selected and characterized through HI test, IFA and VN test. RESULTS: Separate two Fab clones, IV-2 and IV-6, appear positive responses in ELISA and IFA. These two clones can inhibit hemagglutination in HI test and can decrease viral titer by 30 and 20 times in viral neutralization assay, respectively. CONCLUSION: We have got two clones of Fab fragments with neutralization activity to influenza virus Sydney strain (H3N2).
Cells, Cultured↗
[Structural and functional study of prokaryotic enhancer-like element VV1 from vaccinia virus].
Enhancer VV1 (about 283 bp) is selected as the target to analyze its structure and function systemically. Stepwise deletion experiment is used to identify the functional domain of VV1 element. The results suggest that the 20 bp at 5' terminal and 20 bp at 3' terminal are important to the activity of VV1, for without either of them its activity decreased greatly. Furthermore, the 30-50 bp at 5' terminal is essential to its activity, without which will lead to complete loss of its activity. By random mutagenesis assay it is found that base mutation can regulate the activity of enhancer VV1 positively or negatively. The more the activities of mutants descend, the more mutations take place. For singlebase mutation, the activities change relatively little, and most of the mutations always occur in the 50 bp at the 5' terminal.
Base Sequence↗
Optimal management of postpartum hemorrhage.
OBJECTIVE: To review the management of postpartum hemorrhage (PPH). METHODS: Fifteen cases of severe PPH were retrospectively analyzed for clinical parameters and management. RESULTS: Nine patients had a hysterectomy while selective arterial embolization was carried out in 7 cases. One patient had focus clearance. The main causes of postpartum hemorrhage requiring operative management were disseminated intravascular coagulation (DIC), uterine arteriovenous fistula and malformation, placental abnormality, uterine myoma and laceration. CONCLUSION: Upon recognition of postpartum hemorrhage, the most effective management should be initiated. Every effort should be made to stabilize the patient and maintain her reproductive capability.
Adult↗
[Changes of microarousal in OSAS patients during CPAP].
OBJECTIVE: To study the mechanism of microarousal, its clinical meaning and value in the diagnosis and treatment of sleep apnea-hypopnea syndrome (SAHS). METHODS: 270 snorers (218 men, 58 women) mean aged 48 years underwent standard polysomnography (PSG), from which AHI, sleep latency (SL), number of oxygen desaturation >/= 4% per hour (ODI(4)) and microarousal index (MAI) were calculated. The overnight PSG recordings were also repeated during nCPAP in 28 patients, who have filled in the Epworth Sleep Score (ESS) before and after the treatment to evaluate the improvement of daytime sleepiness. RESULTS: Of the 270 snorers, there were 247 SAHS patients. Their AHI, ODI(4), MAI and SL were (43 +/- 27)/h, (44 +/- 23)/h, (29 +/- 16)/h and (12 +/- 17) min, respectively. AHI and MAI, ODI(4) and MAI were both positively correlated (r = 0.38, both P < 0.001). MAI and SL were negatively correlated (r = -0.15, P = 0.02), while AHI and SL, ODI(4) and SL were not correlated (r = -0.09, -0.02, P > 0.1). Of the 28 patients after CPAP, ODI(4) decreased from (48 +/- 25)/h to (4 +/- 9)/h, MAI decreased from (27 +/- 18)/h to (15 +/- 9)/h. The ESS and SL indicated that subjective and objective sleepiness improved. CONCLUSIONS: Microarousals with at least 3 seconds EEG changes can be scored by computerized EEG analysis. MAI can reflect the severity of daytime sleepiness. MAI is complementary to AHI in the diagnosis and treatment of SAHS. After nCPAP, the patients' MAIs decreased and daytime sleepiness improved.
Adult↗
[Important prognostic factors in patients with skull base erosion from nasopharyngeal carcinoma after radiotherapy].
OBJECTIVE: To evaluate the long-term outcome and prognostic factors in patients with skull base erosion from nasopharyngeal carcinoma (NPC) after initial radiation therapy. METHODS: From January 1985 to December 1986, 100 patients (71 male, 29 female) with the diagnosis of NPC were found to have skull base erosion from computed tomography (CT). The mean age was 41 (16-66) years. Ninety-six patients had World Health Organization (WHO) type III undifferentiated carcinoma while four had type I carcinomas. Metastatic workup including chest radiography, liver ultrasound and liver function test were negative. All patients underwent external beam radiotherapy alone to 66-80 Gy over 6-8 weeks. Daily fraction size of 2 Gy was delivered utilizing cobalt-60 or linear accelerator. No patient received chemotherapy. All patients were followed up at regular intervals after irradiation. Median follow-up was 22.3 months (2 months-174 months). Overall survival of the cohort was computed by the Kaplan-Meier method. Potential prognostic factors on survival were examined. Multivariate analyses was performed using Cox regression model. RESULTS: One, three, five, and ten year overall survival rates for the cohort were 79%, 38%, 27% and 13%, respectively. However, in the sub-group of patients with both anterior cranial nerves (I-VIII) and posterior cranial nerve (IX-XII) involvement had a five-year survival of only 7.7%. Causes of death included local recurrence (59 patients), distant metastases (21 patients), both local recurrence and distant metastases (1 patient) and unrelated causes (5 patients). After multivariate analysis, complete recovery of cranial nerve involvement, cranial nerves palsy and recovery of headache after irradiation were found to be independent prognostic factors in this cohort. CONCLUSION: This report presents one of the longest follow-ups of patients with nasopharyngeal carcinoma invading skill base. It demonstrates the importance of cranial nerves involvement as well as recovery of headache and cranial nerve palsy. These factors should be evaluated carefully from history and physical examination as well as imaging studies. Currently available magnetic resonance imaging (MRI) is highly recommended as an additional test. A subgroup of patients with skull base involvement had long-term survival after radiotherapy alone. More aggressive strategy such as combined chemo-radiotherapy and altered fractionation radiotherapy may improve outcome in patients with poor prognostic factors.
Adolescent↗
[Cross reticular bone grass used in slotted acetabular augmentation].
OBJECTIVES: To investigate the technique of cross reticular bone grass used in slotted acetabular augmentation ( SAA), and enrich the surgical procedures in the treatment of the DDH. METHODS: Thirty seven cases were treated with cross reticular bone grass used in SAA, including developmental dysplasia of the hip (DDH) and coaxial plana caused by Legg-Perthes disease. RESULTS: SAA provided an easy way to shape an adept acetabulum with cancellous bone graft. After the operation a stable hip was obtained. Thirty cases were good, 2 remained limping, 1 had a limitation of abduction of the hip. CONCLUSIONS: SAA is a safe and effective way to provide an adequate coverage of the femoral head. It is a developed shelf procedure with good stability and for a surgical frame of the hip. SAA method is safe and technically simple.
Acetabulum↗
In-situ sampling and separation of RNA from individual mammalian cells.
In this investigation RNA was directly sampled and separated at the single-cell level (without extraction) by capillary electrophoresis (CE). Laser-induced fluorescence (LIF) was employed to detect ethidium bromide-labeled RNA molecules under native conditions. Hydroxypropylmethylcellulose was used as a matrix for molecular sieving. Additives to the polymer solution included poly(vinylpyrrolidone) to eliminate the electroosmotic flow and mannitol to enhance the separation. Peak identities were confirmed as RNA by enzymatic treatment with RNase I. The individual Chinese Hamster Ovary (CHO-K1) cells were injected into a capillary and the cells were lysed online with sodium dodecyl sulfate (SDS) solutions before running electrophoresis. Low molecular mass (LMM) RNAs as well as larger fragments (tentatively identified as 18S and 28S ribosomal RNA by comparison with the literature) were detected with this system, which corresponds to a detected amount of approximately equals 10-20 pg of RNA/cell. A Proteinase K study showed that proteins incorporated with RNA molecules were eliminated by SDS treatment and thus did not influence the migration of RNA. Experiments were also performed with this technique to detect nucleic acid damage. Changes in the peak pattern were detected in the cells treated with hydrogen peroxide, which meant that strand breaks occurred in DNA and RNA. It was found that 60 mM caused the most severe damage to the nucleic acids.
Animals↗
Physical mapping of the barley stem rust resistance gene rpg4.
The barley stem rust resistance gene rpg4 was physically and genetically localized on two overlapping BAC clones covering an estimated 300-kb region of the long arm of barley chromosome 7(5H). Initially, our target was mapped within a 6.0-cM region between the previously described flanking markers MWG740 and ABG391. This region was then saturated by integrating new markers from several existing barley and rice maps and by using BAC libraries of barley cv. Morex and rice cv. Nipponbare. Physical/genetic distances in the vicinity of rpg4 were found to be 1.0 Mb/cM, which is lower than the average for barley (4 Mb/cM) and lower than that determined by translocation breakpoint mapping (1.8 Mb/cM). Synteny at high resolution levels has been established between the region of barley chromosome 7(5H) containing the rpg4 locus and the subtelomeric region of rice chromosome 3 between markers S16474 and E10757. This 1.7-cM segment of the rice genome was covered by two overlapping BAC clones, about 250 kb of total length. In barley the markers S16474 and E10757 genetically delimit rpg4, lying 0.6 cM distal and 0.4 cM proximal to the locus, respectively.
Blotting, Southern↗
Inheritance of ventilatory behavior in rodent models.
Studies in mice and rats support the hypothesis that ventilation and its components (frequency and tidal volume) are determined to a significant extent by genetic mechanisms. The question can no longer be 'is there a genetic effect?' but rather 'how strong is the genetic component?' and 'what genes are involved?' The computational analyses of selectively bred animals now offer powerful tools to begin to dissect the genetic factors that track with ventilatory traits. Control of the conditions in the colony and in the laboratory are keys to reducing the environmental 'noise' and increasing the likelihood of detecting gene loci that correlate quantitatively with phenotype values before and during the response to chemosensory challenges. Knowing the chromosomal location of genes for ventilation will then permit the identification of proteins systems responsible for the structural and functional components for respiration.
Animals↗
Molecular cloning and expression patterns of mouse cartilage oligomeric matrix protein gene.
OBJECTIVE: To develop transgenic mice harboring mutations in the COMP gene as animal models for pseudoachondroplasia (PSACH) and multiple epiphyseal dysplasia (MED), autosomal dominant disorders characterized by early onset osteoarthritis and epiphyseal abnormalities. As a first step in generating a mouse model for COMP mutations, we have cloned the cDNA of mouse COMP and examined its tissue expression pattern. DESIGN: Total mRNA was isolated from the skeletal tissues of newborn C57BL/6j mice and used as a template for oligo(dT) first-strand cDNA synthesis. The cDNA was used for PCR amplification of COMP using three oligonucleotide primer pairs designed from the published rat COMP cDNA sequence. Nested PCR was used to complete the sequence between the amplified fragments. The entire cDNA was sequenced and the expression pattern of the corresponding transcripts examined by Northern hybridizations. RESULTS: A full-length COMP cDNA was isolated. Analysis showed that the entire translated region of the mouse COMP gene is 2268 bp and the derived amino acid sequence shows 90% homology to human COMP. Of eight adult mouse non-cartilage tissues tested, COMP expression was detected only in testis.
Achondroplasia↗
A rapid and sensitive reporter gene that uses green fluorescent protein expression to detect chemicals with estrogenic activity.
A reporter gene sequence was constructed within a eukaryotic expression vector. The altered plasmid contained 2 sequential estrogen response elements (ERE) coupled to a human phosphoglycerate kinase (PGK) promoter inserted upstream from a cDNA sequence encoding enhanced green fluorescent protein (GFP) with a 3'-polyadenylation signal. The plasmid was linearized and transfected into MCF-7 cells, a human breast cancer-derived line that expresses the estrogen receptor (ER). No selectable marker was present in the plasmid, requiring stably transfected cells to be selected by fluorescence-activated cell sorting based on GFP expression after the cells were treated with 10(-9) M 17beta-estradiol (E2). Stably transfected MCF-7 cells (MCF7-ERE) exhibited 2000-3000 times more fluorescence at 488 nm excitation and 512 nm emission than non-transfected cells. MCF7-ERE cells exhibited a linear increase in GFP expression induced over a range of 10(-12) M E2, a concentration giving 2 times the background expression, to maximal expression at 3 x 0(-10) M E2. From the maximal level, GFP expression plateaued, and then declined when E2 was increased to the highest concentration tested, 10(-7) M. 4-Hydroxytamoxifen (TFN-OH) treatment of cells produced a dose-dependent inhibition of E2-induced GFP expression, indicating the interaction of ER in the regulation of GFP gene expression. A series of estrogenic chemicals were evaluated for their capacity to induce GFP expression in MCF7-ERE cells, showing induced expression of GFP at concentrations 2-4 log units higher than the E2 concentration giving maximal GFP expression. The ERE-PGK-GFP reporter gene system is capable of rapid GFP expression in the presence of low concentrations of E2, and of quantifying estrogenicity of chemicals compared with a standard curve of the natural ligand, 17beta-estradiol.
Cell Division↗
[Functional and structural analysis of a prokaryotic enhancer-like element in Escherichia coli MC1061 strain].
Cat and lacZ genes were used as reporter gene and three prokaryotic enhancer-like element (MC2, MC8 and MC9) were identified in the genomic DNA of MC1061 strain. All three fragments can improve the expression of lacZ gene by 2-5 times with the orientation independence. The results of in vivo transcription and Dot blot hybridization assays suggested that MC8 regulated the expression of lacZ at transcription level. Stepwise deletion expreriments showed the functional domain of MC8 located at 450-950 bp, and in regions 450-600 bp and 840-950 bp contain at least one functional loci. Sequence data indicated three are 3 A + T rich sections in MC8, 2 of them are in the functional loci.
Enhancer Elements, Genetic↗
[Functional and structural study of the prokaryotic enhancer-like element VV16 from vaccinia virus genome].
An enhancer-like element VV16 from Vaccinia virus genome DNA was obtained by using the plasmid with CAT reporter gene. Sequence analysis showed the element of 112 bp is a part of the DNA-dependent RNA polymerase, polyA polymerase and DNA polymerase (RPO30 gene). It contains 4 AT-rich regions. Detection of beta-galactosidase activity showed that VV16 in the positive direction can increase the activity 9.0 times and VV16 in the negative direction can increase 4.1 times. The RNA dot blotting confirmed the enhancing activity of the element are on the transcription level. DNA deletion experiment indicated the sequences of 10 bp at the 5' end and 12 bp at the 3' end in the element are important to its function and the sequence from nt76 to nt82 is essential to its activity.
Enhancer Elements, Genetic↗
[Expression, purification and identification of human IFN-alpha 2 b/HBV Pre S2 fusion protein].
OBJECTIVE: To express a fusion protein of human interferon-a2b and HBV Pre S2 in E.coli for the purpose of investigating anti-HBV immunomodulatory protein. METHODS: Human interferon-a2b and HBV Pre S2 encoding genes were amplified from plasmid templates through PCR, then fused and cloned into plasmid pBV220 through engineering technique to generate expression plasmid pBV-IFN-Pre S2. The plasmid was transfected into E. coli to produce fusion protein. RP-HPLC and ion-exchange chromatography were employed to purify fusion protein. RESULTS: 27 kDa fusion protein was expressed up to 15% of total bacterial protein in E. coli. After purification, the purity of fusion protein reached 95% of total protein. Anti-viral assay showed that IFN-Pre S2 protein induced a VSV-resistant activity of 1.25 x 10(8) lU/mg protein in Wish cell line, similar to the bioactivity of original recombinant human IFN-alpha 2b. ELISA data showed that IFN-Pre S2 protein had antigenicities of both human IFN-alpha 2b and HBV Pre S2. In addition, fusion protein showed the feature of binding to polymeric human serum albumin (PHSA). CONCLUSIONS: The bifunctional fusion protein was efficiently expressed in E. coli. The work provided initial evidence for studying PHSA-receptor-targeting IFN-alpha 2b,which might have potential application for the treatment of HBV infection.
Amino Acid Sequence↗