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OBJECTIVES@#To identify the differentially expressed genes (DEGs) during the pathogenesis of periodontitis by bioinformatics analysis.@*METHODS@#GEO2R was used to screen DEGs in GSE10334 and GSE16134. Then, the overlapped DEGs were used for further analysis. g:Profiler was used to perform Gene Ontology analysis and pathway analysis for upregulated and downregulated DEGs. The STRING database was used to construct the protein-protein interaction (PPI) network, which was further visua-lized and analyzed by Cytoscape software. Hub genes and key modules were identified by cytoHubba and MCODE plug-ins, respectively. Finally, transcription factors were predicted via iRegulon plug-in.@*RESULTS@#A total of 196 DEGs were identified, including 139 upregulated and 57 downregulated DEGs. Functional enrichment analysis showed that the upregulated DEGs were mainly enriched in immune-related pathways including immune system, viral protein interaction with cytokine and cytokine receptor, cytokine-cytokine receptor interaction, leukocyte transendothelial migration, and chemokine receptors bind chemokines. On the contrary, the downregulated DEGs were mainly related to the formation of the cornified envelope and keratinization. The identified hub genes in the PPI network were CXCL8, CXCL1, CXCR4, SEL, CD19, and IKZF1. The top three modules were involved in chemokine response, B cell receptor signaling pathway, and interleukin response, respectively. iRegulon analysis revealed that IRF4 scored the highest.@*CONCLUSIONS@#The pathogenesis of periodontitis was closely associated with the expression levels of the identified hub genes including CXCL8, CXCL1, CXCR4, SELL, CD19, and IKZF1. IRF4, the predicted transcription factor, might serve as a dominant upstream regulator.
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Humanos , Biología Computacional , Perfilación de la Expresión Génica , Análisis por Micromatrices , Periodontitis , Mapas de Interacción de ProteínasRESUMEN
Objective:To investigate the relationship between atherosclerotic plaque characteristics of the middle cerebral artery(MCA)and acute cerebral ischemic symptoms by using high-resolution magnetic resonance imaging(HR-MRI).Methods:A retrospective analysis of clinical and imaging data was performed in 136 patients[100 males, aged(60.8±11.4)years]with MCA atherosclerotic plaque who underwent HR-MRI.Patients were divided into the acute symptomatic group(n=73)and the non-acute asymptomatic group(n=63)according to whether the patients had acute ischemic symptoms in the MCA territory within two weeks.The basic demographic characteristics, clinical risk factors, MCA plaque enhancement, maximum plaque length, maximum wall thickness, ratio of maximum plaque length to maximum wall thickness and luminal stenosis were compared between the two groups.Binary Logistic regression was used to estimate the association between MCA plaque characteristics and acute ischemic symptoms in the corresponding vascular territory.Results:Compared with the non-acute symptomatic group, the acute symptomatic group had a greater prevalence of diabetes mellitus(50.7% or 30/73 vs. 30.2% or 19/63, χ2=5.882, P=0.015), a higher occurrence of enhanced plaques(87.7 % or 64/73 vs.46.0% or 29/63, χ2=27.118, P<0.001), greater maximum plaque length[(6.7±3.7 mm) vs.(4.9±2.3)mm, t=-3.330, P=0.001], greater maximum wall thickness[(1.5±0.8)mm vs.(1.0±1.0)mm, t=-2.231, P=0.027]and more severe luminal stenosis[(66.4±31.3)% vs. (30.7±25.3) %, t=-7.354, P<0.001]. Logistic regression analysis showed that MCA enhanced plaque( OR=4.492, 95% CI: 1.762-11.449, P=0.002)and luminal stenosis( OR=1.032, 95% CI: 1.018-1.047, P<0.001)were independently associated with acute ischemic symptoms. Conclusions:Compared with luminal stenosis, MCA enhanced plaque has a stronger correlation with acute ischemic symptoms and significant plaque enhancement may be an important indication of its instability.
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OBJECTIVE@#The effects of different tube currents and voltages on image quality and radiation dose were studied to provide a theoretical basis for low-dose cone beam computed tomography (CBCT) scanning in children.@*METHODS@#Different tube currents and voltages were used to scan the incisor area of fresh Bama pig heads by CBCT. The radiation dose was recorded, and image quality was evaluated.@*RESULTS@#As the tube current or voltage decreased, the radiation dose and image quality gradually decreased. The computed tomographic dose index (CTDIvol) of 90 kV, 2.5 mA and 60 kV, 7.0 mA were all 1.7 mGy. The image quality score of the former was higher than that of the latter, and the difference between them was statistically significant (P<0.05).@*CONCLUSIONS@#Low-dose CBCT scanning appears to be able to reduce the necessary tube current during imaging by improving image quality.
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Animales , Niño , Humanos , Tomografía Computarizada de Haz Cónico , Estudios de Factibilidad , Cabeza , Dosis de Radiación , PorcinosRESUMEN
Objective@#To investigate the value of zTE ASL MRA in the follow-up of interventional treatment of intracranial aneurysm at 1.5 T, using DSA as gold standard.@*Methods@#Patients with intracranial aneurysms who underwent coil embolization with or without stent were enrolled in this study. Both TOF MRA and zTE ASL MRA were performed on a 1.5T whole body scanner (MR360, GE, USA) equipped with an 8 channel head coil, and DSA was performed within one week of the MR examinations. Aneurysmal remnant and intra-stent opacity were analyzed. SE, PE, PPV, NPV of two MRA modalities in aneurysm recanalization detection were calculated. Kappa coefficient was used to determine the inter-reader and intra-reader reproducibility. Paired t test was used to test the visibility of in-stent lumen on two kinds of MRA.@*Results@#A total of 24 patients (27 aneurysms) were included in this study, 23 aneurysms were treated with stent assisted embolization, four coil embolization. Thirteen cases of aneurysm remnant were detected by DSA, 15 by zTE ASL and 11 by TOF MRA. zTE ASL MRA had a relatively higher SE (100%) and NPV(100%) as compared with TOF MRA. The Kappa value in identification of aneurysm remnant was 0.85 between zTE MRA and DSA and 0.70 between TOF MRA and DSA, respectively. The inter-reader reproducibility was good (Kappa 0.70), while the intra-reader reproducibility was excellent(Kappa 0.85). There was statistical significance in the scoring results of the in-stent lumen visibility.@*Conclusion@#zTE ASL MRA proved to be a better imaging modality as compared to TOF MRA to evaluate the endovascular treatment effectiveness of intracranial aneurysms, especially for assessing the aneurysmal recurrence and in-stent lumen visibility.
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Purpose To characterize the middle cerebral artery atherosclerotic plaque and investigate its relationship with infarction patterns by using 3.0T high resolution magnetic resonance imaging (HRMRI).Materials and Methods Forty-nine patients with intracranial atherosclerosis underwent HRMRI.The characteristics of the plaques of middle cerebral artery were investigated,including morphology,distribution and enhancement.Patients were categorized as two groups (strong/mild and none) according to the strength of plaque enhancement,then clinical data were compared between the two groups and the risk factors were investigated.Acute infarction was classified as three subtypes (single/multiple perforating artery occlusion/arterial embolism) basedon diffusion weighted imaging,and the plaque characteristics of each subtype were investigated.Results Sixty-five plaques were identified in middle cerebral artery of 49 patients,62 plaques (95.4%) were eccentric,31 plaques (50.0%) were located at the ventral wall.Patients with low levels of high-density lipoprotein were significantly more prevalent in strong enhancement group (56.7% vs.26.3%,P<0.05).The percentage of strong enhancement plaque in arterial embolism group (88.9%) was significantly higher than non-arterial embolism group (36.4%) (P<0.05).Conclusion Middle cerebral artery plaque distribution is correlated with ischemic stroke,strong enhancement plaque is associated with its vulnerability.HRMRI can provide information to predict the ischemic event and infarction pattern.
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Objective To study the value of magnetic resonance vessel wall imaging in assessing the atherosclerotic plaque burden of rabbit model.Methods We built up abdominal atherosclerotic animal model in 30 New Zealand rabbits by high lipid diet combined with abdominal artery denudation.The animals were divided into 3 groups randomly,which were the 1-week group,1-month group and 2-months group.The MRI and histology examination were carried out at relative time points.The correlations of area or thickness of vessel wall by MRI with histology examination were analyzed.Results Among the 30 rabbits,3 died due to anesthesia or surgery,one rabbit model failed because of the thin vessel,and another 3 died of diarrhea or inflammation during the high lipid diet feeding.Eventually,totally 23 rabbits fulfilled the examinations (7 in 1-week group,7 in 1-month group and 9 in 2-months group).The vessel wall area of histology examination grew larger along with the post-surgery duration,from 1.7663 mm2of 1-week group to 2.4371 mm2 of the 1-month group till 3.5978 mm2 of 2-months group,with statistic significant difference among 3 groups (F=5.052,P=0.017).There were strong correlations of area or thickness vessel wall resulted from MRI with histology examination(r=0.688,0.642;P=0.001,0.002).Conclusions High resolution MR vessel wall imaging technique may evaluate and follow up the plaque burden in the early stage of atherosclerosis.
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The present study was to determine the effect of c-SRC on the viability of human cervical cancer HeLa cells and the expression of phosphorylated signal transducer and activator of transcription-3 (p-STAT3) of the cell. Post-transfection of c-SRC RNA interference vector, RT-PCR and Western blot were utilized to observe the contents of c-SRC mRNA and protein, respectively, in HeLa cells. The MTT was used to observe the viability of the cells. Cell cycle was observed by flow cytometry. The content of p-STAT3 in the cells was also investigated after knockdown of c-SRC. Knockdown of c-SRC significantly decreased the contents of c-SRC mRNA and protein in the cells. The viability of the cells decreased by 23.1%, 29.3%, 38.6% and 45.0% (all P < 0.05), respectively, after the cells were transfected with c-SRC RNA interference vector for 24, 48, 72, and 96 h. The number of S-phase cells decreased by 5.6%, 10.0%, 15.2% and 19.9% (all P < 0.05), respectively, after transfection of c-SRC RNA interference vector for 24, 48, 72, and 96 h. The content of p-STAT3 also decreased when c-SRC was knockdowned. Compared with the control group, after treatment of HeLa cells with STAT3 inhibitor Piceatannol for 24, 48, 72, and 96 h, the cell viability decreased by 23.8%, 29.7%, 37.3% and 45.4% (all P < 0.05), respectively, while increase of c-SRC content could not reverse the inhibitory effect. These results suggest that the inhibited viability of HeLa cells caused by knockdown of c-SRC is associated with the decreased content of p-STAT3 protein.
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Femenino , Humanos , Supervivencia Celular , Regulación Neoplásica de la Expresión Génica , Técnicas de Silenciamiento del Gen , Genes src , Genética , Células HeLa , Fosforilación , ARN Mensajero , Genética , Factor de Transcripción STAT3 , Genética , Metabolismo , TransfecciónRESUMEN
<p><b>OBJECTIVE</b>To evaluate (18)F-fluorodeoxyglucose-position-emission tomography-computer tomography imaging ((18)F-FDG-PET-CT) on head and neck squamous cell carcinoma(HNSCCA) and lymph node metastasis.</p><p><b>METHODS</b>(18)F-FDG-PET-CT imaging of 20 patients with HNSCCA was evaluated retrospectively.</p><p><b>RESULTS</b>All the primary tumors were correctly diagnosed by (18)F-PET-CT imaging and SUV(avg) of the primary tumors was (6.22 +/- 2.20). All the sensitivity, specificity, positive predictive value and the negative predictive value were 100%. In detecting lymph node metastasis, the sensitivity was 51%, specificity 97.7%, false positive rate 2.3%, false negative rate 49%, positive predictive value 82%, and negative predictive value 91.2%.</p><p><b>CONCLUSIONS</b>(18)F-FDG-PET-CT imaging was valuable in detecting HNSCCA and lymph node metastasis. SUV was helpful for differential diagnosis between benign or malignant tumors but it needs further study to determine the cutoff SUV for differentiating lymph node metastasis.</p>
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Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Carcinoma de Células Escamosas , Diagnóstico por Imagen , Patología , Fluorodesoxiglucosa F18 , Neoplasias de Cabeza y Cuello , Diagnóstico por Imagen , Patología , Metástasis Linfática , Tomografía de Emisión de Positrones , Métodos , Tomografía Computarizada por Rayos XRESUMEN
<p><b>AIM</b>To observe the effect of vitamin E (VE) on ovarian apoptosis-related protein Bcl-2 and Bax and its impact on antioxidant capacity in aged female rats and to study the senility-delaying effect and mechanism of VE on ovary.</p><p><b>METHODS</b>Natural aging female rats were given different doses of exogenous VE. Then apoptosis regulatory protein Bcl-2, Bax expression in ovarian grandlose cells were detected by using immunohistochemical methods and Western blot. The contents of serum total superoxide dismutase (SOD) activity and malondialdehyde (MDA) were detected by using biochemical methods.</p><p><b>RESULTS</b>Contrasted with adult control group, the level of Bcl-2 expression in Senile control group was lower and the level of Bax expression was higher (P < 0.01), Serum SOD activity decreased and the level of MDA significantly increased (P < 0.01). Contrasted with senile control group, the level of Bcl-2 expression increased in VE group, the level of Bax expression decreased (P < 0.05), the level of MDA expression significantly decreased (P < 0.01).</p><p><b>CONCLUSION</b>VE can regulate apoptosis-related protein Bcl-2, Bax expression and confront free radical damage which contribute to a protective effect for ovarian grandiose cells.</p>
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Animales , Femenino , Ratas , Envejecimiento , Antioxidantes , Farmacología , Apoptosis , Células de la Granulosa , Biología Celular , Ovario , Biología Celular , Proteínas Proto-Oncogénicas c-bcl-2 , Metabolismo , Ratas Wistar , Vitamina E , Farmacología , Proteína X Asociada a bcl-2 , MetabolismoRESUMEN
<p><b>OBJECTIVE</b>To investigate the effects of intrauterine growth retardation (IUGR) caused by malnutrition during pregnancy on the acetylation of histone H3 and expression of histonedeacetylase1(HDAC1) in the hepar of the adult offspring and to explore the relationship between them.</p><p><b>METHODS</b>Male 8-week-old offspring from maternal protein-malnutrition dams were studied. The expression of HDAC1 mRNA in the hepar was measured by fluorescent quantization RT-PCR. The levels of hepatic nuclear HDAC1 protein and acetylation of histone H3/K9 were assessed by Western blot.</p><p><b>RESULTS</b>The hepatic HDAC1 mRNA expression in IUGR rats was reduced to 54% of that of normal control rats (t=2.042, p<0.05). A decline in nuclear expression of HDAC1 protein (438 +/- 47) was also noted when compared with normal controls (1,128 +/- 110) (t=2.179, p<0.05). In contrast, the percentage of acetylated histone H3/K9 in IUGR rats (17.3 +/- 1.6%) increased significantly compared with that of normal control rats (10.5 +/- 1.2%) (t=3.597, p<0.01). The level of acetylated histone H3/K9 was negatively correlated with the HDAC1 protein concentration (r=-0.781, p<0.01).</p><p><b>CONCLUSIONS</b>Increased hepatic acetylation of histone H3 in the IUGR offspring might be caused by decreased HDAC1 expression in nuclear protein. This may contribute to the transcription change of some genes in the hepar.</p>
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Animales , Femenino , Masculino , Embarazo , Ratas , Acetilación , Retardo del Crecimiento Fetal , Metabolismo , Histona Desacetilasa 1 , Genética , Histonas , Metabolismo , Hígado , Metabolismo , ARN Mensajero , Ratas WistarRESUMEN
<p><b>OBJECTIVE</b>To determine the molecular mechanisms linking intrauterine growth restriction (IUGR) to adult type 2 diabetes mellitus, the effect of IUGR on the hepatic post-receptor insulin-signaling pathway was investigated in the adult offspring.</p><p><b>METHODS</b>The IUGR model was prepared by maternal protein-malnutrition. Western blotting analysis was undertaken to assess hepatic expression of insulin receptor substrate (IRS-2), phosphoinositol 3-kinase (PI-3K), protein kinase B (PKB), phosphorylated PKB-Ser473 and glycogen synthase kinase (GSK) 3 in 8-week-old male IUGR rats.</p><p><b>RESULTS</b>The basal levels of PI-3K protein decreased in IUGR rats compared with normal controls (p<0.01), whereas GSK-3beta protein level significantly increased in IUGR rats (p<0.01). Both PKB and phosphorylated PKB-Ser473 protein levels significantly decreased in the liver of IUGR rats compared with normal controls (p<0.01)). After insulin administration, phosphorylated PKB-Ser473 significantly increased to 182% of basal level in control rats(p<0.01); However, phosphorylation of PKB which responded to insulin was markedly blunted in IUGR rats compared with controls and only increased to 123% of basal level (p<0.05).</p><p><b>CONCLUSIONS</b>The level of PI-3K and PKB and phosphorylated PKB-Ser473 expression decreased in the liver of IUGR rats, whereas the levels of GSK-3beta protein increased. It may contribute to the pathogenesis of insulin resistance in the IUGR rats.</p>
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Animales , Femenino , Masculino , Ratas , Retardo del Crecimiento Fetal , Metabolismo , Glucógeno Sintasa Quinasa 3 , Glucógeno Sintasa Quinasa 3 beta , Proteínas Sustrato del Receptor de Insulina , Resistencia a la Insulina , Hígado , Metabolismo , Fosfatidilinositol 3-Quinasas , Fisiología , Proteínas Proto-Oncogénicas c-akt , Ratas Wistar , Transducción de Señal , FisiologíaRESUMEN
Objective To compare radiation dose and image quality between prospective electrocardiograph(ECG)-triggered axial seau and retrospective ECG-gated helical scan in coronary 64-slice CT angiography(CTA).Methods Seventy-seven consecutive patients[group A.Average body mass index (BMI):24.6,heart rate<70 bpm]underwent 64-slice CTA using prospective ECG-triggered axial scan protocol(120 kV,mA tailored to BMI).For each patient,the simulated radiation dose using retrospective ECG-gated scan protocol without ECG-driven X-ray current modulation technology was calculated and recorded at sanle kV and mA.Retrospective ECG-gated scan protocol was performed on 30 consecutive patients in another group(group B.Average BMI:23.9,heart rate<70 bpm).The image quality was blindly evaluated between group A and B(paired t-test was used and P<0.05 as a significant difference).Results There Was a significant difference(t=18.50,P<0.01)between radiation dose of group A (3.37 mSv)and that of group B(18.13 mSv),decreased by 81.4%.The image quality of group A could fulfill clinical diagnostic needs.The average radiation dose of using simulated helical scan without optimization was 17.29 mSv,which wag similar to that of group B(18.13 mSv)(t=0.87,P>0.05).Condusion Prospective ECG-triggered axial scan in 64-slice coronary CTA Call significantly reduce radiation exposure and the image quality can fulfill clinical diagnostic needs.
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<p><b>OBJECTIVE</b>To study the molecular genetic etiology of a Chinese pedigree with basal cell nevus syndrome.</p><p><b>METHODS</b>The proband and his affected mother and a unaffected individual in the pedigree were chosen and peripheral blood was collected from them for DNA. Direct sequencing was performed to detect the mutations of PTCH gene. In order to further confirm the results of sequence analysis, all available family members were analyzed with genetic linkage analysis using 3 highly polymorphic microsatellite DNA markers in the region of 9q22.3-q31.</p><p><b>RESULTS</b>No mutations of PTCH gene was detected in the proband's mother, one synonymous mutation was detected in the proband. Linkage analysis showed that the Lod scores of the 3 markers were: D9S283, Z = -2.11 (theta = 0.00); D9S1690, Z = -2.95 (theta = 0.00); D9S1677, Z = -5.94 (theta = 0.00).</p><p><b>CONCLUSIONS</b>In this pedigree, mutation of PTCH gene is not related to the underlying pathogenesis of the syndrome.</p>
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Femenino , Humanos , Masculino , Pueblo Asiatico , Genética , Síndrome del Nevo Basocelular , Genética , Ligamiento Genético , Mutación , Receptores Patched , Receptor Patched-1 , Linaje , Receptores de Superficie Celular , GenéticaRESUMEN
Objective To assess the effective length of jejunal graft when the 3~(rd) intestinal artery is u- tilized as vascular pedicle and afford a reliable theoretic base for clinical esophageal reconstruction.Methods In 32 formalin preserved and 21 fresh cadaver specimens,the diameter of 1st to 5th intestinal arteries and diameter of arterial arches are measured with linear calibre.Measure the length of jejunum that can be harves- ted as graft when the arches are extended.In the 21 fresh specimens,the 1st,2nd,4th and 5th intestinal ar- teries are ligated,acetic ester stained with red dye were injected into the lumen of 3rd intestinal artery via catheter.Extent of distribution of the arteries to the jejunum was observed.And then red ABS solution was in- jected into the 3rd intestinal artery to make into cast specimen.The blood supply distribution of jejunum through 3rd intestinal artery-arterial arch and communicating system were observed again.Results The di- ameter of the 3rd intestinal artery was the largest among the 1st to 5th intestinal arteries.The length of jejunum vascularized by 3rd intestinal artery can be as long as (142.2?62.3) (69.0~206.60cm) in acetic ester in- filtrated specimens.While in ABS east specimen,the average available extent of donor jejunum was(30.8?7.3) (23.0~37.3cm).Conclusion As observed by this applied anatomy study,the jejunum graft vascu- larized by 3rd intestinal artery alone has sufficient length to meet the need of esophageal reeonstrution.
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<p><b>OBJECTIVE</b>To investigate injury to epidermal melanocyte by Q-switched Alexandrite laser.</p><p><b>METHODS</b>Multiple biopsies were performed on 5 patients with nevus of Ota from before irradiation to 1 year after irradiation. Fourteen specimens were obtained for light microscopy, and 17 for transmission electron microscopy.</p><p><b>RESULTS</b>Melanosomes in epidermal melanocytes were both smaller in size and fewer in number than those in dermal melanocytes. Immediately after irradiation, focal extracellular vacuoles of the basal layer could be observed under light microscopy. Most epidermal melanocytes underwent mild or moderate injury in the form of vacuolated melanosomes, swollen mitochondria, dilation of endoplasmic reticulum, and expansion of extracellular space, retaining intact cell membranes. Normal structures were restored 5 months to 1 year after irradiation, with no depigmentation or hyperpigmentation as seen by light microscopy.</p><p><b>CONCLUSION</b>Injury of melanosomes in epidermal melanocytes is reversible.</p>
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Adolescente , Adulto , Femenino , Humanos , Berilio , Usos Terapéuticos , Terapia por Láser , Rayos Láser , Melanocitos , Efectos de la Radiación , Microscopía Electrónica , Nevo de Ota , Patología , Radioterapia , Neoplasias Cutáneas , Patología , RadioterapiaRESUMEN
<p><b>OBJECTIVE</b>To evaluate the clinical response of Nevus of Ota to Q-switched Alexandrite laser, and analyze factors that influence the treatment outcome.</p><p><b>METHODS</b>A total of 522 patients treated with Q-switched Alexandrite laser were included in the study. Single and multiple variate analyses of various factors were performed.</p><p><b>RESULTS</b>Satisfactory result was observed in all patients, none of whom developed scarring. Clinical response was improved with additional treatment sessions. The clinical response of the 20 - 27-week treatment interval group was significantly better than that of the 12 - 19-week interval group, but showed no significant difference as compared with both the 28 - 35 and > or = 36-week interval group. Zygomatic, buccal and frontal areas showed better response than ocular and temporal areas. Treatment session, interval, and fluence were significant factors identified by multivariate analysis.</p><p><b>CONCLUSIONS</b>Q-switched Alexandrite laser is an ideal method for treating Nevus of Ota without injury. The number of treatment sessions is more important than interval or fluence.</p>
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Adolescente , Adulto , Niño , Preescolar , Femenino , Humanos , Lactante , Masculino , Persona de Mediana Edad , Neoplasias Faciales , Patología , Cirugía General , Terapia por Láser , Métodos , Nevo de Ota , Patología , Cirugía General , Trastornos de la Pigmentación , Neoplasias Cutáneas , Patología , Cirugía GeneralRESUMEN
A gene replacement/disruption system of Amycolatopsis mediterranei U32 was developed based on the established electroporation conditions as well as appropriate selective markers. Through two-step selection, ahbas gene in U32 was replaced by a promoterless alpha-amylase gene constructed on the plasmid pDK110 of E. coli. The first single-crossover and the second double-crossover frequencies were approximately 0.5%-0.7% and 2%, respectively. Denaturation of the plasmid pDK110 increased the integration frequency about 7-10 folds, while electric shock treatment of the single-crossover recombinants increased the frequency of second crossover recombination about 5 folds. Employing denatured DNA fragments containing an apramycin-resistance gene flanked with regions of the respective genes, One-step disruption of rifO and amrA genes of U32 was also achieved with an efficiency of 30-50 transformants per microgram of DNA.
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Actinomycetales , Genética , ADN Bacteriano , Genética , Farmacorresistencia Microbiana , Genética , Genes Bacterianos , Genética , Mutagénesis , Nebramicina , Farmacología , Plásmidos , Genética , Recombinación GenéticaRESUMEN
Objective To evaluate the clinical significance of the diameter of the esophageal hiatus on multislice spiral CT(MSCT)and to present the MSCT manifestations of esophageal hiatus hernia (EHH).Methods(1)The distance between diaphragmatic crura(DDC),which indicated the diameter of esophageal hiatus,was measured in 140 normal adult patients on their thoracic and/or abdomenal CT images.(2)The DDC of 56 patients with EHH diagnosed by barium examination was measured on MSCT, and the MSCT findings were analyzed retrospectively.Results(1)The DDC of 140 normal adult cases were(13.44?4.41)mm on average and increased with age.The mean DDCs of patients under the age of 59 year-old(80 cases)and over 60-year-old(60 cases)were 11.03?2.10 mm and 16.67?4.64 mm respective]y,there was a significant difference(t=8.762,P