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1.
Clin. transl. oncol. (Print) ; 23(10): 2036-2045, oct. 2021. ilus
Article in English | IBECS | ID: ibc-223374

ABSTRACT

Purpose To explore the application value of multi-slice spiral CT (MSCT), magnetic resonance imaging (MRI) combined with gastric contrast-enhanced ultrasonography in the diagnosis of T staging of gastric cancer. Methods The subjects of study were 109 gastric cancer patients with T stages admitted to our hospital for diagnosis and treatment from December 2016 to December 2018. All the patients were examined with MSCT, MRI and gastric contrast-enhanced ultrasonography before operation to observe corresponding imaging results. T staging of gastric cancer patients was conducted according to the examination results, which was then compared with postoperative pathological staging. It was performed to analyze the accuracy of the three diagnostic methods and combined diagnosis of gastric cancer T staging. Results The sensitivity of MSCT in the diagnosis of T staging of gastric cancer was 60.00%, 67.74%, 72.22%, 76.47%, the specificity was 95.24%, 88.46%, 86.30%, 94.56% and the diagnostic coincidence rate was 87.16%, 82.57%, 81.65%, 91.74%; the sensitivity of MRI in the diagnosis of T staging of gastric cancer was 68.00%, 70.97%, 77.78%, 76.47%, the specificity was 92.86%, 88.46%, 91.78%, 95.65%, and the diagnostic coincidence rate was 87.16%, 83.49%, 87.16%, 92.66%; the sensitivity of gastric contrast-enhanced ultrasonography in the diagnosis of T staging of gastric cancer was 80.00%, 83.87%, 86.11%, 82.35%, the specificity was 97.62%, 92.31%, 91.78%, 97.83%, and the diagnostic coincidence rate was 93.58%, 89.91%, 89.91%, 95.41%; the sensitivity of combined MSCT, MRI and gastric contrast-enhanced ultrasonography in the diagnosis of T staging of gastric cancer was 88.00%, 93.55%, 97.22%, 94.12%; the specificity was 100%, 97.44%, 95.89%, 98.91%; and the diagnostic coincidence rate was 97.25%, 96.33%, 96.33%, 98.17%, respectively (AU)


Subject(s)
Humans , Stomach Neoplasms/diagnostic imaging , Stomach Neoplasms/pathology , Magnetic Resonance Imaging , Tomography, Spiral Computed , Neoplasm Staging , Ultrasonography
2.
Clin Transl Oncol ; 23(10): 2036-2045, 2021 Oct.
Article in English | MEDLINE | ID: mdl-33830443

ABSTRACT

PURPOSE: To explore the application value of multi-slice spiral CT (MSCT), magnetic resonance imaging (MRI) combined with gastric contrast-enhanced ultrasonography in the diagnosis of T staging of gastric cancer. METHODS: The subjects of study were 109 gastric cancer patients with T stages admitted to our hospital for diagnosis and treatment from December 2016 to December 2018. All the patients were examined with MSCT, MRI and gastric contrast-enhanced ultrasonography before operation to observe corresponding imaging results. T staging of gastric cancer patients was conducted according to the examination results, which was then compared with postoperative pathological staging. It was performed to analyze the accuracy of the three diagnostic methods and combined diagnosis of gastric cancer T staging. RESULTS: The sensitivity of MSCT in the diagnosis of T staging of gastric cancer was 60.00%, 67.74%, 72.22%, 76.47%, the specificity was 95.24%, 88.46%, 86.30%, 94.56% and the diagnostic coincidence rate was 87.16%, 82.57%, 81.65%, 91.74%; the sensitivity of MRI in the diagnosis of T staging of gastric cancer was 68.00%, 70.97%, 77.78%, 76.47%, the specificity was 92.86%, 88.46%, 91.78%, 95.65%, and the diagnostic coincidence rate was 87.16%, 83.49%, 87.16%, 92.66%; the sensitivity of gastric contrast-enhanced ultrasonography in the diagnosis of T staging of gastric cancer was 80.00%, 83.87%, 86.11%, 82.35%, the specificity was 97.62%, 92.31%, 91.78%, 97.83%, and the diagnostic coincidence rate was 93.58%, 89.91%, 89.91%, 95.41%; the sensitivity of combined MSCT, MRI and gastric contrast-enhanced ultrasonography in the diagnosis of T staging of gastric cancer was 88.00%, 93.55%, 97.22%, 94.12%; the specificity was 100%, 97.44%, 95.89%, 98.91%; and the diagnostic coincidence rate was 97.25%, 96.33%, 96.33%, 98.17%, respectively. Statistical analysis revealed that the sensitivity, specificity and diagnostic coincidence rate of combined detection of the three methods were significantly higher than those of single detection (P < 0.05). CONCLUSION: Combined use of MSCT, MRI and gastric contrast-enhanced ultrasonography can significantly improve the diagnostic sensitivity, specificity and diagnostic coincidence rate of T staging of gastric cancer. It may provide a certain reference value for guiding the selection of clinical therapeutic approaches and evaluation of curative effect.


Subject(s)
Magnetic Resonance Imaging/methods , Multidetector Computed Tomography/methods , Stomach Neoplasms/diagnostic imaging , Ultrasonography/methods , Adult , Aged , Contrast Media/administration & dosage , Female , Humans , Male , Middle Aged , Multimodal Imaging/methods , Neoplasm Staging/methods , Sensitivity and Specificity , Stomach Neoplasms/pathology
4.
Zhonghua Xin Xue Guan Bing Za Zhi ; 48(4): 302-307, 2020 Apr 24.
Article in Chinese | MEDLINE | ID: mdl-32370481

ABSTRACT

Objective: To analyze the impact of different admission ways on the timeliness of percutaneous coronary intervention and in-hospital mortality in patients with acute ST-segment elevation myocardial infarction (STEMI). Methods: A total of 1 044 patients with STEMI, who received primary percutaneous coronary intervention (PPCI) in 9 hospitals in Chengdu from January 2017 to June 2019, were retrospectively enrolled. According to the admission ways, patients were divided into ambulance group (n=100), self-transport group (n=584) and transferred group (n=360). Timeliness and in-hospital mortality were compared among the groups. Indicators of timeliness included the time from symptoms onset to arrive at the hospital, the time from arrive at the hospital to balloon and the total myocardial ischemia time (the time from symptoms to balloon). Multivariate logistic regression analysis was used to verify whether the admission ways was the determinant for in-hospital death in STEMI patients receiving PPCI. Results: The median total myocardial ischemic time in the ambulance group was significantly shorter than that in the self-transport group (180.0 (135.0, 282.0) minutes vs. 278.0 (177.8, 478.5) minutes, P<0.05) and the transferred group (180.0 (135.0, 282.0) minutes vs. 301.0 (204.3, 520.8) minutes, P<0.05). The median time from symptoms to door was as follows: ambulance group0.05). Multivariate logistic regression analysis showed that admission way was not significantly associated with in-hospital death (P>0.05). Conclusions: STEMI patients, who are admitted through the medical emergency system, are more likely to receive timely interventional therapy.Different admission ways have no impact on in-hospital mortality.


Subject(s)
Percutaneous Coronary Intervention , ST Elevation Myocardial Infarction , Humans , Retrospective Studies , Time Factors , Treatment Outcome
5.
Bone Joint J ; 101-B(2): 221-226, 2019 02.
Article in English | MEDLINE | ID: mdl-30700117

ABSTRACT

AIMS: The aim of this study was to characterize the factors leading to transfemoral amputation after total knee arthroplasty (TKA), as well as the rates of mortality and functional independence after this procedure in these patients. PATIENTS AND METHODS: This was a multicentre retrospective review with a prospective telephone survey for the assessment of function. All patients with a TKA who subsequently required transfemoral amputation between January 2001 and December 2015 were included. Demographic information, medical comorbidities, and postoperative mortality data were collected. A 19-item survey was used for the assessment of function in surviving patients. RESULTS: A total of 111 patients were included. Their mean age was 61.0 years (42.0 to 88.0) at the time of TKA, with a subsequent mean of 3.7 operations (0 to 15) over a mean period of 6.1 years (0.05 to 30.1) before amputation. The indication for amputation was chronic infection in 97 patients (87.4%). The rate of five-year survival was 51.7%, and advanced age (p = 0.001) and renal failure (p = 0.045) were associated with an increased risk of mortality. Of the 62 surviving patients, 34 completed the survey; 32 (94.1%) owned a prosthesis but only 19 (55.9%) used it; 19 (55.9%) primarily used a wheelchair for mobility; 27 (79.5%) had phantom pain; and 16 (47.1%) required chronic pain medication. Only 18 patients (52.9%) were satisfied with the quality of life. CONCLUSION: Patients with complications after TKA, in whom transfemoral amputation is considered, should be made aware of the high rate of mortality and the poor functional outcome in the survivors. Alternative forms of treatment including arthrodesis of the knee should be investigated.


Subject(s)
Activities of Daily Living , Amputation, Surgical , Arthroplasty, Replacement, Knee/adverse effects , Femur/surgery , Ischemia/surgery , Lower Extremity/surgery , Prosthesis-Related Infections/surgery , Adult , Aged , Aged, 80 and over , Amputation, Surgical/mortality , Amputation, Surgical/rehabilitation , Female , Humans , Lower Extremity/blood supply , Male , Middle Aged , Prosthesis-Related Infections/mortality , Quality of Life , Recovery of Function , Retrospective Studies
6.
Oncogene ; 37(33): 4633-4634, 2018 08.
Article in English | MEDLINE | ID: mdl-29973686

ABSTRACT

In this article, the authors recently noticed that the tubulin blots in Figs. 2a and 6a were inadvertently misplaced during the preparation of these figures due to their similarity. The amended versions of the figures are now shown below. The conclusions of this paper are not affected. The authors sincerely apologize for these errors.

7.
J Dent Res ; 97(1): 14-22, 2018 Jan.
Article in English | MEDLINE | ID: mdl-28922615

ABSTRACT

With the increase in numbers of joint replacements, spinal surgeries, and dental implantations, there is an urgent need to combat implant-associated infection. In addition to stringent sterile techniques, an efficacious way to prevent this destructive complication is to create new implants with antimicrobial properties. Specifically, these implants must be active in the dental implant environment where the implant is bathed in the glycoprotein-rich salivary fluids that enhance bacterial adhesion, and propagation, and biofilm formation. However, in designing an antimicrobial surface, a balance must be struck between antimicrobial activity and the need for the implant to interact with the bone environment. Three types of surfaces have been designed to combat biofilm formation, while attempting to maintain osseous interactions: 1) structured surfaces where topography, usually at the nanoscale, decreases bacterial adhesion sufficiently to retard establishment of infection; 2) surfaces that actively elute antimicrobials to avert bacterial adhesion and promote killing; and 3) surfaces containing permanently bonded agents that generate antimicrobial surfaces that prevent long-term bacterial adhesion. Both topographical and elution surfaces exhibit varying, albeit limited, antimicrobial activity in vitro. With respect to covalent coupling, we present studies on the ability of the permanent antimicrobial surfaces to kill organisms while fostering osseointegration. All approaches have significant drawbacks with respect to stability and efficacy, but the permanent surfaces may have an edge in creating a long-term antibacterial environment.


Subject(s)
Anti-Infective Agents/therapeutic use , Dental Implants , Anti-Infective Agents/administration & dosage , Bacterial Adhesion/drug effects , Biofilms/drug effects , Dental Implantation, Endosseous/adverse effects , Dental Implantation, Endosseous/methods , Dental Implantation, Endosseous/microbiology , Dental Implants/adverse effects , Dental Implants/microbiology , Humans , Osseointegration/drug effects
8.
Oncogene ; 35(49): 6293-6308, 2016 12 08.
Article in English | MEDLINE | ID: mdl-27181208

ABSTRACT

Cancer cells predominantly metabolize glucose by glycolysis to produce energy in order to meet their metabolic requirement, a phenomenon known as Warburg effect. Although Warburg effect is considered a peculiarity critical for survival and proliferation of cancer cells, the regulatory mechanisms behind this phenomenon remain incompletely understood. We report here that eukaryotic elongation factor-2 kinase (eEF-2K), a negative regulator of protein synthesis, has a critical role in promoting glycolysis in cancer cells. We showed that deficiency in eEF-2K significantly reduced the uptake of glucose and decreased the productions of lactate and adenosine triphosphate in tumor cells and in the Ras-transformed mouse embryonic fibroblasts. We further demonstrated that the promotive effect of eEF-2K on glycolysis resulted from the kinase-mediated restriction of synthesis of the protein phosphatase 2A-A (PP2A-A), a key factor that facilitates the ubiquitin-proteasomal degradation of c-Myc protein, as knockdown of eEF-2K expression led to a significant increase in PP2A-A protein synthesis and remarkable downregulation of c-Myc and pyruvate kinase M2 isoform, the key glycolytic enzyme transcriptionally activated by c-Myc. In addition, depletion of eEF-2K reduced the ability of the transformed cells to proliferate and enhanced the sensitivity of tumor cells to chemotherapy both in vitro and in vivo. These results, which uncover a role of the eEF-2K-mediated control of PP2A-A in tumor cell glycolysis, provide new insights into the regulation of the Warburg effect.


Subject(s)
Elongation Factor 2 Kinase/metabolism , Protein Phosphatase 2/biosynthesis , Animals , Breast Neoplasms/enzymology , Breast Neoplasms/genetics , Cell Line, Tumor , Elongation Factor 2 Kinase/genetics , Female , Heterografts , Humans , MCF-7 Cells , Mice , Mice, Nude , Protein Phosphatase 2/genetics , Transfection
9.
Herz ; 41(4): 326-30, 2016 Jun.
Article in English | MEDLINE | ID: mdl-26612056

ABSTRACT

BACKGROUND: Renalase is a novel secretory amino oxidase expressed in the kidney and heart. To study the protective mechanism of renalase in local heart tissue, we established a low-expression renalase model with lentivirus (LV)-mediated RNA interference technology. MATERIALS AND METHODS: Three renalase-targeting oligonucleotides were designed after analyzing the mRNA of renalase. LV particles were prepared with LV expression systems (using the Trono 3 plasmid component system), after which LV-RNLS-shRNAs and LV-NC-shRNA were transfected into H9C2 cells in different cell culture plates. The optimal oligonucleotide was screened by real-time PCR and Western blot. These techniques were also used to detect renalase gene expression in the heart tissue. RESULTS: In the cell screening experiment, the efficacy of the inhibition of renalase mRNA expression was 93.7 % and that of renalase protein expression was 83.1 % in H9C2 cells. When the oligonucleotide was injected into the pericardial cavities of the SD rats on the 10th day, it inhibited 63.9 % of the expression of renalase protein in the heart tissue. CONCLUSION: LV-RNLS-RNAi (19813-1) can be used to establish an optimal renalase low-expression model for further research on the renalase system.


Subject(s)
Down-Regulation/physiology , Gene Knockdown Techniques/methods , Lentivirus/genetics , Monoamine Oxidase/metabolism , Myocardium/enzymology , RNA Interference/physiology , Animals , Gene Expression Regulation, Enzymologic , Monoamine Oxidase/genetics , Rats , Rats, Sprague-Dawley , Rats, Transgenic , Transfection/methods
10.
CPT Pharmacometrics Syst Pharmacol ; 4(9): 498-506, 2015 Sep.
Article in English | MEDLINE | ID: mdl-26451329

ABSTRACT

Identifying potential adverse drug reactions (ADRs) is critically important for drug discovery and public health. Here we developed a multiple evidence fusion (MEF) method for the large-scale prediction of drug ADRs that can handle both approved drugs and novel molecules. MEF is based on the similarity reference by collaborative filtering, and integrates multiple similarity measures from various data types, taking advantage of the complementarity in the data. We used MEF to integrate drug-related and ADR-related data from multiple levels, including the network structural data formed by known drug-ADR relationships for predicting likely unknown ADRs. On cross-validation, it obtains high sensitivity and specificity, substantially outperforming existing methods that utilize single or a few data types. We validated our prediction by their overlap with drug-ADR associations that are known in databases. The proposed computational method could be used for complementary hypothesis generation and rapid analysis of potential drug-ADR interactions.

11.
J Hosp Infect ; 85(4): 297-302, 2013 Dec.
Article in English | MEDLINE | ID: mdl-24358509

ABSTRACT

BACKGROUND: The efficacy of antibiotics in preventing surgical site infections (SSIs) depends on the timing of administration relative to the start of surgery. However, currently, both the timing of and recommendations for administration vary substantially. AIM: To determine how the economic value from the hospital perspective of preoperative antibiotics varies with the timing of administration for orthopaedic procedures. METHODS: Computational decision and operational models were developed from the hospital perspective. Baseline analyses looked at current timing of administration, while additional analyses varied the timing of administration, compliance with recommended guidelines, and the goal time-interval. FINDINGS: Beginning antibiotic administration within 0-30 min prior to surgery resulted in the lowest costs and SSIs. Operationally, linking to a pre-surgical activity, administering antibiotics prior to incision but after anaesthesia-ready time was optimal, as 92.1% of the time, antibiotics were administered in the optimal time-interval (0-30 min prior to incision). Improving administration compliance from 80% to 90% for this pre-surgical activity results in cost savings of $447 per year for a hospital performing 100 orthopaedic operations a year. CONCLUSION: This study quantifies the potential cost-savings when antibiotic administration timing is improved, which in turn can guide the amount hospitals should invest to address this issue.


Subject(s)
Anti-Bacterial Agents/administration & dosage , Anti-Bacterial Agents/economics , Antibiotic Prophylaxis/economics , Antibiotic Prophylaxis/methods , Orthopedic Procedures/methods , Preoperative Care/methods , Surgical Wound Infection/prevention & control , Costs and Cost Analysis , Humans , Time Factors
12.
Bone Joint J ; 95-B(11): 1450-2, 2013 Nov.
Article in English | MEDLINE | ID: mdl-24151261

ABSTRACT

Louis Pasteur once said that: "Fortune favours the prepared mind." As one of the great scientists who contributed to the fight against infection, he emphasised the importance of being prepared at all times to recognise infection and deal with it. Despite the many scientific discoveries and technological advances, such as the advent of antibiotics and the use of sterile techniques, infection continues to be a problem that haunts orthopaedic surgeons and inflicts suffering on patients. The medical community has implemented many practices with the intention of preventing infection and treating it effectively when it occurs. Although high-level evidence may support some of these practices, many are based on little to no scientific foundation. Thus, around the world, there is great variation in practices for the prevention and management of periprosthetic joint infection. This paper summaries the instigation, conduct and findings of a recent International Consensus Meeting on Surgical Site and Periprosthetic Joint Infection.


Subject(s)
Anti-Bacterial Agents/therapeutic use , Arthritis, Infectious/drug therapy , Joint Prosthesis/adverse effects , Prosthesis-Related Infections/drug therapy , Arthritis, Infectious/diagnosis , Humans , Prosthesis-Related Infections/prevention & control , Prosthesis-Related Infections/therapy
13.
J Bone Joint Surg Br ; 88(11): 1448-53, 2006 Nov.
Article in English | MEDLINE | ID: mdl-17075088

ABSTRACT

The aim of this study was to compare the results in patients having a quadriceps sparing total knee replacement (TKR) with those undergoing a standard TKR at a minimum follow-up of two years. All patients who had a TKR with a high-flex posterior-stabilised prosthesis prior to December 2002 were reviewed retrospectively. There were 57 patients available for follow-up. Those with a quadriceps sparing TKR had less pain peri-operatively with a greater degree of flexion at all the post-operative visits and at the final follow-up, but their operations took longer, with less accurate radiological alignment. There was no difference in the complications and in the Knee Society scores between the two groups at the final follow-up. Total knee replacement through a quadriceps sparing approach has some peri-operative advantages over the standard incision. At a minimum follow-up of two years the clinical results were similar to those with a standard incision, but the radiological outcomes of the quadriceps sparing group were inferior.


Subject(s)
Arthroplasty, Replacement, Knee/methods , Quadriceps Muscle/surgery , Adult , Aged , Aged, 80 and over , Female , Humans , Knee Joint/physiopathology , Knee Joint/surgery , Male , Middle Aged , Movement/physiology , Osteoarthritis, Knee/physiopathology , Osteoarthritis, Knee/surgery , Postoperative Complications , Range of Motion, Articular , Retrospective Studies , Treatment Outcome
14.
Arch Otolaryngol Head Neck Surg ; 127(11): 1385-9, 2001 Nov.
Article in English | MEDLINE | ID: mdl-11701080

ABSTRACT

Tumors found in the cerebellopontine angle are predominantly vestibular schwannomas. Mixed tumors found within the cerebellopontine angle are thought to be exceedingly rare and exclusively associated with neurofibromatosis 2. We report a case of a mixed tumor composed of Schwann and meningeal cell proliferations in a patient who was not diagnosed as having neurofibromatosis 2. Mixed tumors composed of neoplastic Schwann and meningeal cells have rarely been reported. However, new evidence indicates that these mixed tumors may be more common than was previously thought and may have an interrelated mechanism of pathogenesis. Although the case we describe does not fulfill the current diagnostic criteria for neurofibromatosis 2, a presumptive diagnosis was given, suggesting that the current diagnostic criteria for neurofibromatosis 2 may be too narrow.


Subject(s)
Cerebellar Neoplasms/diagnosis , Cerebellopontine Angle , Meningeal Neoplasms/diagnosis , Neuroma, Acoustic/diagnosis , Cerebellar Neoplasms/surgery , Cerebellopontine Angle/diagnostic imaging , Cerebellopontine Angle/pathology , Cerebellopontine Angle/surgery , Diagnosis, Differential , Humans , Magnetic Resonance Imaging , Male , Meningeal Neoplasms/surgery , Middle Aged , Nasopharyngeal Neoplasms/surgery , Neurofibromatosis 2/diagnosis , Neuroma, Acoustic/surgery , Tomography, X-Ray Computed
15.
Arch Otolaryngol Head Neck Surg ; 127(8): 921-5, 2001 Aug.
Article in English | MEDLINE | ID: mdl-11493199

ABSTRACT

BACKGROUND: Earlier studies have mapped the autosomal recessive nonsyndromic deafness locus, DFNB15, to chromosomes 3q21.3-q25.2 and 19p13.3-13.1, identifying one of these chromosomal regions (or possibly both) as the site of a deafness-causing gene. Mutations in unconventional myosins cause deafness in mice and humans. One unconventional myosin, myosin 1F (MYO1F), is expressed in the cochlea and maps to chromosome 19p13.3-13.2. OBJECTIVE: To evaluate MYO1F as a candidate gene for deafness at the DFNB15 locus by determining its genomic structure and screening each exon for deafness-causing mutations to identify possible allele variants of MYO1F segregating in the DFNB15 family. METHODS: We used radiation hybrid mapping to localize MYO1F on chromosome arm 19p. We next determined its genomic structure using multiple long-range polymerase chain reaction experiments. Using these data, we completed mutation screening using single-stranded conformational polymorphism analysis and direct sequencing of affected and nonaffected persons in the original DFNB15 family. RESULTS: Radiation hybrid mapping placed MYO1F in the DFNB15 interval, establishing it as a positional candidate gene. Its genomic structure consists of 24 coding exons. No mutations or genomic rearrangements were found in the original DFNB15 family, making it unlikely that MYO1F is the disease-causing gene in this kindred. CONCLUSIONS: Although we did not find MYO1F allele variants in one family with autosomal recessive nonsyndromic hearing loss, the gene remains an excellent candidate for hereditary hearing impairment. Given its wide tissue expression, MYO1F might cause syndromic deafness.


Subject(s)
Chromosomes, Human, Pair 19 , Deafness/genetics , Myosins/genetics , Alleles , Animals , Chromosome Mapping , DNA, Complementary/genetics , Exons/genetics , Humans , Mice , Mutation , Pedigree , Polymerase Chain Reaction , Polymorphism, Single-Stranded Conformational , Radiation Hybrid Mapping , Sequence Analysis, DNA
16.
Am J Physiol Gastrointest Liver Physiol ; 279(5): G1023-30, 2000 Nov.
Article in English | MEDLINE | ID: mdl-11053000

ABSTRACT

Endothelial nitric oxide synthase (eNOS)-derived nitric oxide (NO) contributes to hepatic vascular homeostasis. The aim of this study was to examine whether delivery of an adenoviral vector encoding eNOS gene to liver affects vasomotor function in vivo and the mechanism of NO production in vitro. Rats were administered adenoviruses encoding beta-galactosidase (AdCMVLacZ) or eNOS (AdCMVeNOS) via tail vein injection and studied 1 wk later. In animals transduced with AdCMVLacZ, beta-galactosidase activity was increased in the liver, most prominently in hepatocytes. In AdCMVeNOS-transduced animals, eNOS protein levels and catalytic activity were significantly increased. Overexpression of eNOS diminished baseline perfusion pressure and constriction in response to the alpha(1)-agonist methoxamine in the perfused liver. Transduction of cultured hepatocytes with AdCMVeNOS resulted in the targeting of recombinant eNOS to a perinuclear distribution and binding with the NOS-activating protein heat shock protein 90. These events were associated with increased ionomycin-stimulated NO release. In summary, this is the first study to demonstrate successful delivery of the recombinant eNOS gene to liver in vivo and in vitro with ensuing NO production.


Subject(s)
Adenoviridae/genetics , Gene Transfer Techniques , Hepatocytes/enzymology , Liver/metabolism , Nitric Oxide Synthase/genetics , Animals , Calcimycin , Hepatocytes/cytology , In Vitro Techniques , Ionophores , Lac Operon , Liver/cytology , Male , Nitric Oxide/metabolism , Nitric Oxide Synthase Type III , RNA Processing, Post-Transcriptional/physiology , Rats , Rats, Inbred F344 , Recombinant Proteins/genetics , beta-Galactosidase/genetics
17.
Biochemistry ; 39(23): 6881-90, 2000 Jun 13.
Article in English | MEDLINE | ID: mdl-10841769

ABSTRACT

Calmodulin (CaM) is an essential eukaryotic protein that binds calcium ions cooperatively at four EF-hand binding sites to regulate signal transduction pathways. Interactions between the apo domains of vertebrate CaM reduce the calcium affinities of sites I and II below their intrinsic values, allowing sequential opening of the two hydrophobic clefts in CaM. Viable domain-specific mutants of Parameciumcalmodulin (PCaM) differentially affect ion channels and provide a unique opportunity to dissect the roles of the two highly homologous half-molecule domains. Calcium binding induced an increase in the level of ordered secondary structure and a decrease in Stokes radius in these mutants; such changes were identical in direction to those of wild type CaM, but the magnitude depended on the mutation. Calcium titrations monitored by changes in the intrinsic fluorescence of Y138 in site IV showed that the affinities of sites III and IV of wild type PCaM were (i) higher than those of the same sites in rat CaM, (ii) equivalent to those of the same sites in PCaM mutants altered between sites I and II, and (iii) higher than those of PCaM mutants modified in sites III and IV. Thus, calcium saturation drove all mutants to undergo conformational switching in the same direction but not to the same extent as wild type PCaM. The disruption of the allosteric mechanism that is manifest as faulty channel regulation may be explained by altered properties of switching among the 14 possible partially saturated species of PCaM rather than by an inability to adopt two end-state conformations or target interactions similar to those of the wild type protein.


Subject(s)
Calcium/metabolism , Calmodulin/chemistry , Ion Channels/metabolism , Paramecium/genetics , Protein Conformation/drug effects , Amino Acid Sequence , Animals , Binding Sites , Calmodulin/genetics , Circular Dichroism , Models, Molecular , Molecular Sequence Data , Mutation , Protein Binding , Protein Structure, Secondary , Rats , Sequence Alignment , Spectrometry, Fluorescence , Spectrophotometry, Ultraviolet , Thermodynamics
18.
Ann Hum Genet ; 64(Pt 3): 189-96, 2000 May.
Article in English | MEDLINE | ID: mdl-11409409

ABSTRACT

Stereocilia of the inner ear play an integral role in the mechanotransduction of sound. Their structural support is derived from actin filaments and actin-binding proteins. We have identified a novel actin-binding protein, 2E4-kaptin (KPTN), which appears to be involved in this structural network. Using double label immunofluorescence, we now show that KPTN extends beyond the barbed ends of actin filaments at the tips of stereocilia, and using cloned human cDNA, we mapped KPTN to chromosome 19q13.4. A combination of FISH, radiation hybrid mapping and YAC screening localized KPTN between markers D19S412 and NIB1805, making this gene an excellent functional and positional candidate for DFNA4, a form of autosomal dominant non-syndromic hearing loss. We identified a second family with inherited deafness that also maps to the DFNA4 region. To screen KPTN for deafness-causing mutations, we first determined its genomic structure and then completed a mutational analysis by direct sequencing and SSCP in affected family members. Although no deafness-causing mutations were identified in the coding region, KPTN remains an excellent candidate gene for hearing loss; by synteny, its murine orthologue also remains a candidate gene for the Nijmegan waltzer (nv) mouse mutant, which has vestibular defects and a variable sensorineural hearing loss.


Subject(s)
Deafness/genetics , Microfilament Proteins/genetics , Adult , Animals , Chickens , Chromosome Mapping , Chromosomes, Human, Pair 19/genetics , Female , Humans , In Situ Hybridization, Fluorescence , Male , Mice , Microscopy, Fluorescence , Molecular Sequence Data , Pedigree , Polymerase Chain Reaction
19.
Trends Pharmacol Sci ; 19(7): 276-86, 1998 Jul.
Article in English | MEDLINE | ID: mdl-9703761

ABSTRACT

Gene therapy involves the transfer of a functional gene into host cells to correct the malfunction of a specific gene or to alleviate the symptoms of a disease. For gene transfer to the cardiovascular system, adenoviral vectors are the most efficient means of transfer. Recently, transfer and functional expression of recombinant nitrio oxide synthase (NOS) genes to cerebral and cardiovascular beds have been demonstrated both ex vivo and in vivo. Here, Alex Chen and colleagues review current progress in the field of vascular NOS gene transfer and the potential use of NOS gene therapy for a number of cardiovascular diseases. Although the feasibility of the NOS gene transfer approach has been demonstrated in animal models, currently available vectors have a number of technical and safety limitations that have to be solved before human NOS gene therapy for cardiovascular disease can be attempted.


Subject(s)
Cardiovascular Diseases/therapy , Cardiovascular System/enzymology , Genetic Therapy , Nitric Oxide Synthase/biosynthesis , Animals , Cardiovascular Diseases/enzymology , Gene Transfer Techniques , Genetic Vectors , Nitric Oxide Synthase/genetics , Recombinant Proteins/biosynthesis
20.
Arterioscler Thromb Vasc Biol ; 18(8): 1231-41, 1998 Aug.
Article in English | MEDLINE | ID: mdl-9714129

ABSTRACT

The current study was designed to determine the effect of recombinant endothelial nitric oxide synthase (eNOS) gene expression on endothelium-dependent relaxations to bradykinin in isolated canine basilar, coronary, or femoral arteries. Arterial rings were exposed ex vivo (30 minutes at 37 degrees C) to an adenoviral vector encoding either the eNOS gene (AdCMVeNOS) or the beta-galactosidase reporter gene (AdCMVbeta-Gal). Twenty-four hours after transduction, transgene expression was evident mainly in the adventitia. Expression of recombinant proteins was much higher in basilar arteries than in coronary or femoral arteries. Rings of control, AdCMVbeta-Gal, and AdCMVeNOS arteries with and without endothelium were suspended for isometric tension recording. Levels of cGMP were measured by radioimmunoassay. In AdCMVeNOS basilar arteries with endothelium, relaxations to low concentrations of bradykinin (3 x 10(-11) to 10(-9) mol/L) were significantly augmented. In contrast, in coronary and femoral arteries with endothelium, AdCMVeNOS transduction did not affect relaxations to bradykinin. Removal of the endothelium abolished bradykinin-induced relaxations in control and AdCMVbeta-Gal basilar arteries. However, in basilar arteries transduced with AdCMVeNOS even when the endothelium was removed, stimulation with bradykinin (3 x 10(-11) to 10(-9) mol/L) caused relaxations as well as increases in cGMP production. The relaxations to bradykinin were completely blocked by an NOS inhibitor, NG-nitro-L-arginine methyl ester. Electron microscopic analysis revealed that recombinant eNOS protein was expressed in fibroblasts of the basilar artery adventitia. These results suggest that genetically modified adventitial fibroblasts may restore production of NO in cerebral arteries without endothelium. Our findings support a novel concept in vascular biology that fibroblasts in the adventitia may play a role in the regulation of vascular tone after successful transfer and expression of recombinant eNOS gene.


Subject(s)
Arteries/metabolism , Endothelium, Vascular/metabolism , Gene Expression Regulation, Enzymologic/physiology , Nitric Oxide Synthase/genetics , Nitric Oxide/biosynthesis , Adenoviridae/genetics , Animals , Arteries/drug effects , Arteries/ultrastructure , Bradykinin/pharmacology , Cyclic GMP/metabolism , Dogs , Endothelium, Vascular/drug effects , Endothelium, Vascular/ultrastructure , Gene Expression Regulation, Enzymologic/drug effects , Gene Transfer Techniques , Genes, Reporter/physiology , Genetic Vectors/genetics , Histocytochemistry , Humans , Microscopy, Electron , Nitric Oxide Synthase/drug effects , Nitric Oxide Synthase/ultrastructure , Nitric Oxide Synthase Type III , Recombinant Proteins/drug effects , Recombinant Proteins/genetics , Recombinant Proteins/ultrastructure , beta-Galactosidase/metabolism
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