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1.
Clin Transl Oncol ; 23(3): 572-581, 2021 Mar.
Article in English | MEDLINE | ID: mdl-32705492

ABSTRACT

PURPOSE: This study aimed to down-regulate LINC00667 and inhibit apoptosis and fibrosis of renal tubular epithelial cells through miR-34c. METHODS: Altogether, 98 patients with chronic kidney disease treated in our hospital were selected as the study group, and 67 normal people were selected as the control group. Epithelial cells of proximal convoluted tubules in human renal cortex were purchased. TGF-ß1 was used to induce fibrosis of HK-2 renal tubular epithelial cells. The expression of LINC00667, miR-34c, type I collagen (Col 1) and type III collagen (Col 3) were detected by qRT-PCR and WB. RESULTS: LINC00667 was highly expressed in cancer tissues and HK-2, while miR-34c was poorly expressed. Inhibition of LINC00667 and over-expression of miR-34c could inhibit the proliferation and invasion of chronic kidney disease cells, but increase the apoptosis rate. Down-regulation of LINC00667 could significantly reduce of Col 1 and Col 3 in renal interstitial fibroblasts induced by TGF-ß1, while up-regulation of miR-34c could also achieve this effect. Double luciferase report confirmed that there was a targeted regulatory relationship between LINC00667 and miR-34c. CONCLUSION: LINC00667 could reduce the proliferation and invasion of chronic kidney disease cells, increase the apoptosis rate by regulating miR-34c, and improve renal fibrosis.


Subject(s)
Epithelial Cells/physiology , Kidney Tubules, Proximal/metabolism , MicroRNAs/metabolism , RNA, Long Noncoding/metabolism , Renal Insufficiency, Chronic/metabolism , Apoptosis , Case-Control Studies , Cell Proliferation , Collagen Type I/metabolism , Collagen Type III/metabolism , Down-Regulation , Epithelial Cells/pathology , Fibroblasts/metabolism , Fibrosis , Humans , Kidney Tubules, Proximal/pathology , Neoplasm Invasiveness , Renal Insufficiency, Chronic/pathology , Reverse Transcriptase Polymerase Chain Reaction , Transforming Growth Factor beta1
2.
Clin Transl Oncol ; 22(6): 928-934, 2020 Jun.
Article in English | MEDLINE | ID: mdl-31571151

ABSTRACT

PURPOSE: Cetuximab (CTX) has been used to treat metastatic colorectal cancer (mCRC) with wild-type (wt) RAS and BRAF genes. Meanwhile HER2 amplification reportedly denoted CTX-resistant mCRC tumors. We investigated whether monitoring of HER2 amplification in circulating DNA allowed early detection of mCRC progression and CTX resistance. METHODS: We analyzed HER2 amplification in circulating DNA at 8-week intervals using ddPCR from 36 patients with RASwt/BRAFwt mCRC, who progressed after CTX treatments between July 2015 and January 2018. RESULTS: Of the 36 patients, 5 (13.9%) exhibited dynamic fluctuations of HER2 amplification in plasma in the course of CTX treatment, of whom 2 were positive for HER2 amplification in matched tumor specimens at baseline (per FISH). All 5 primary sites were left side: 3 rectums and 2 descending colon. HER2 ratio fluctuations in circulating DNA not only reflected changes in tumor volume, but their obvious increases presaged CT-documented progress by an average lead time of 2 months. Interestingly, progression-free survival did not significantly differ between these 5 patients and those without HER2 amplification (HR 1.06, 95% CI 0.40-2.77, P = 0.909). CONCLUSION: Plasma HER2 amplification detected by ddPCR changed over time and predicted resistance to CTX, by an average lead time of 2 months. Further study is needed to validate our findings.


Subject(s)
Cell-Free Nucleic Acids/blood , Cetuximab/therapeutic use , Colorectal Neoplasms/drug therapy , Receptor, ErbB-2/genetics , Adult , Aged , Antineoplastic Agents, Immunological/therapeutic use , Biomarkers, Tumor/blood , Biomarkers, Tumor/genetics , Colorectal Neoplasms/blood , Colorectal Neoplasms/genetics , Colorectal Neoplasms/pathology , Disease Progression , Drug Resistance, Neoplasm/genetics , Female , Gene Amplification , Humans , Male , Middle Aged , Prospective Studies , Receptor, ErbB-2/metabolism , Treatment Outcome
3.
Neotrop Entomol ; 47(3): 362-368, 2018 Jun.
Article in English | MEDLINE | ID: mdl-28965311

ABSTRACT

Sugarcane borers are economically damaging insects with species that vary in distribution patterns both geographically and temporally, and vary based on ecological niche. Currently, identification of sugarcane borers is mostly based on morphological characters. However, morphological identification requires taxonomic expertise. An alternative method to identify sugarcane borers is the use of molecular data. DNA barcoding based on partial cytochrome c oxidase subunit 1 (COI) sequences has proven to be a useful tool for rapid and accurate species determination in many insect taxa. This study was conducted to test the effectiveness of DNA barcodes to discriminate among sugarcane borer species in China. Partial sequences of the COI gene (709 bp) were obtained from six species collected from different geographic areas. Results showed that the pairwise intraspecies genetic distance was < 0.02, whereas the interspecies genetic distance ranged from 0.117 to 0.182. Results from a neighbor-joining tree showed that the six sugarcane borer species were certainly separated. These results suggested that the partial COI sequences had high barcoding resolution in discriminating among sugarcane borer species. Our study emphasized the use of DNA barcodes for identification of the analyzed sugarcane borer species and represents an important step for building a comprehensive barcode library for sugarcane borers in China.


Subject(s)
DNA Barcoding, Taxonomic , Lepidoptera/classification , Phylogeny , Saccharum , Animals , China , DNA, Mitochondrial/genetics , Herbivory
4.
Genet Mol Res ; 15(4)2016 Dec 19.
Article in English | MEDLINE | ID: mdl-28002586

ABSTRACT

Osteosarcoma is a common malignant bone tumor that mainly affects children and adolescents. Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) is a member of the tumor necrosis factor superfamily. Caspase-8 appears in the upstream of apoptosis signaling pathway among caspases. We investigated TRAIL and caspase-8 levels in osteosarcoma patients to determine their correlation with cell proliferation and apoptosis. Osteosarcoma and osteochondroma patients receiving surgery in our hospital were selected. TRAIL and caspase-8 expression levels in tissue were determined by immunohistochemistry, and protein levels in cells were evaluated by western blotting. Human osteosarcoma cell viability was determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. The osteosarcoma and osteochondroma cell cycles and apoptosis were investigated by flow cytometry. Correlation analysis was applied to TRAIL and caspase-8 levels during cell apoptosis. Positive TRAIL and caspase-8 expression rates in osteosarcoma tissue were significantly lower than in the controls (P < 0.05). TRAIL (0.114 ± 0.002) and caspase-8 (0.352 ± 0.124) levels in experimental cells were obviously lower than in the controls (P < 0.05). Osteosarcoma cells in the experimental group demonstrated higher proliferation and lower apoptosis at 24, 48, and 72 h (P < 0.05). The experimental cell number increased in the G1 stage and decreased in the S stage (P < 0.05). TRAIL and caspase-8 proteins showed positive correlation with apoptosis in osteosarcoma (P < 0.05). Human osteosarcoma presented reduced TRAIL and caspase-8 levels with enhanced cell proliferation and reduced apoptosis. TRAIL and caspase-8 expression levels were positively correlated with apoptosis in osteosarcoma.


Subject(s)
Bone Neoplasms/metabolism , Caspase 8/metabolism , Osteochondroma/metabolism , Osteosarcoma/metabolism , TNF-Related Apoptosis-Inducing Ligand/metabolism , Adult , Aged , Apoptosis , Bone Neoplasms/surgery , Cell Proliferation , Cell Survival , Female , Gene Expression Regulation, Neoplastic , Humans , Male , Middle Aged , Osteochondroma/surgery , Osteosarcoma/surgery , Tumor Cells, Cultured , Young Adult
5.
Genet Mol Res ; 15(3)2016 Aug 19.
Article in English | MEDLINE | ID: mdl-27706568

ABSTRACT

In this study, we compared the quality of DNA extracted using the modified CTAB method, from Rheum palmatum leaves preserved using fourteen different methods, including ones used commonly in other species: under ultra-cold (-80°C) temperatures, after drying with an absorbent paper, desiccating using a silica gel, drying at 60°C, in 70% ethanol, absolute ethanol, 70% ethanol supplemented with 50 mM EDTA, SDS-DNA extracting solution, nuclear separation buffer, improved NaCl-CTAB solution, TE-buffer, I-solution, or II-solution. DNA extracted from fresh leaves was used as the control. The quality of extracted DNA was evaluated based on the success of PCR amplification of the ITS2 region and a microsatellite marker. DNA was not extracted from samples preserved in the nuclear separation buffer and II-solution. The purities of DNA extracted from leaves preserved in ultra-cold temperatures, 70% ethanol, and 70% ethanol with 50 mM EDTA, and after desiccating using a silica gel and drying were higher, and comparable to the purity of DNA extracted from fresh leaves, than those of leaves preserved using other methods. In the present study, combined with the PCR amplifications, the preservation using ultra-cold temperatures, silica gel desiccation, or drying, and PCR amplification of the extracted DNA can be used for further molecular studies in R. palmatum.


Subject(s)
DNA, Plant/isolation & purification , Preservation, Biological/methods , Rheum/genetics , Microsatellite Repeats , Plant Leaves/chemistry , Plant Leaves/genetics , Polymerase Chain Reaction/methods , Rheum/chemistry
6.
Genet Mol Res ; 15(2)2016 May 23.
Article in English | MEDLINE | ID: mdl-27323082

ABSTRACT

Invasive plants tend to spread aggressively in new habitats and an understanding of their genetic diversity and population structure is useful for their management. In this study, expressed sequence tag-simple sequence repeat (EST-SSR) markers were developed for the invasive plant species Praxelis clematidea (Asteraceae) from 5548 Stevia rebaudiana (Asteraceae) expressed sequence tags (ESTs). A total of 133 microsatellite-containing ESTs (2.4%) were identified, of which 56 (42.1%) were hexanucleotide repeat motifs and 50 (37.6%) were trinucleotide repeat motifs. Of the 24 primer pairs designed from these 133 ESTs, 7 (29.2%) resulted in significant polymorphisms. The number of alleles per locus ranged from 5 to 9. The relatively high genetic diversity (H = 0.2667, I = 0.4212, and P = 100%) of P. clematidea was related to high gene flow (Nm = 1.4996) among populations. The coefficient of population differentiation (GST = 0.2500) indicated that most genetic variation occurred within populations. A Mantel test suggested that there was significant correlation between genetic distance and geographical distribution (r = 0.3192, P = 0.012). These results further support the transferability of EST-SSR markers between closely related genera of the same family.


Subject(s)
Asteraceae/genetics , Expressed Sequence Tags , Genetics, Population , Microsatellite Repeats/genetics , DNA, Plant/genetics , Genetic Variation
7.
Genet Mol Res ; 15(1)2016 Mar 31.
Article in English | MEDLINE | ID: mdl-27051033

ABSTRACT

Porcine epidemic diarrhea poses significant sanitation problems in the porcine industry, and has negatively affected the economy in recent years. In this study, 48 fecal specimens were collected from piglets from four intensive swine farms located in the Gansu Province of China. The molecular diversity and phylogenetic relationships between porcine epidemic diarrhea viruses (PEDV) prevalent in Gansu were probed, and the resultant proteins were characterized. Sequence analysis of the spike protein (S) genes showed that each specimen had unique characteristics, and that the PEDV1/S/4 strain could be differentiated from the others via a unique mutation of the S gene. The phylogeny of S glycoprotein showed that all strains were clustered into two major groups. The four Gansu PEDV field strains were characterized into different groups; this finding was consistent with the results of the protein characterization prediction. This analysis additionally revealed the unique characteristics of each specimen. The results of this study could be used to elucidate the prevalence of PEDV and contribute to the prevention of PEDV in Gansu.


Subject(s)
Coronavirus Infections/veterinary , Phylogeny , Porcine epidemic diarrhea virus/genetics , Swine Diseases/virology , Animals , China , Coronavirus Infections/virology , Porcine epidemic diarrhea virus/classification , Porcine epidemic diarrhea virus/isolation & purification , Spike Glycoprotein, Coronavirus/genetics , Swine
8.
Genet Mol Res ; 14(4): 12074-84, 2015 Oct 05.
Article in English | MEDLINE | ID: mdl-26505354

ABSTRACT

The association between the CCDC26 rs4295627 single nucleotide polymorphism (SNP) and the glioma risk has been studied previously, but these studies have yielded conflicting results. The aim of the present study is to analyze this association more vigorously, by means of a meta-analysis. A comprehensive literature search was performed in databases PubMed and EMBASE. Six articles including 12 case-control studies in English with 11,368 controls and 5891 cases were eligible for the meta-analysis. We conducted subgroup analyses by the source of controls, ethnicity, and country. Our meta-analysis revealed that the rs4295627 SNP was associated with the glioma risk in a heterozygote model (TG versus TT: odds ratio = 1.35, 95% confidence interval = 1.26-1.45, P = 0.066). Moreover, our results suggested that the rs4295627 SNP was associated with a notably increased risk of glioma among Caucasians except for Swedes in 4 models (the homozygote model, recessive model, dominant model, and additive model). Nonetheless, in Sweden and China, the results showed no associations. No evidence of the publication bias was uncovered. Thus, our meta-analysis suggests that the rs4295627 SNP is associated with an increased risk of glioma. Additional studies are needed to derive more precise conclusion.


Subject(s)
Brain Neoplasms/genetics , Glioma/genetics , Intracellular Signaling Peptides and Proteins/genetics , Polymorphism, Single Nucleotide , Brain Neoplasms/ethnology , Case-Control Studies , China , Glioma/ethnology , Humans , RNA, Long Noncoding , Sweden
9.
Genet Mol Res ; 14(3): 11099-108, 2015 Sep 22.
Article in English | MEDLINE | ID: mdl-26400340

ABSTRACT

Dairy goat is a good model for production of transgenic proteins in milk using somatic cell nuclear transfer (SCNT). However, animals produced from SCNT are often associated with lung deficiencies. We recently produced six transgenic cloned dairy goats harboring the human lactoferrin gene, including three live transgenic clones and three deceased transgenic clones that died from respiratory failure during the perinatal period. Imprinted genes are important regulators of lung growth, and may be subjected to faulty reprogramming. In the present study, first, microsatellite analysis, PCR, and DNA sequence identification were conducted to confirm that these three dead kids were genetically identical to the transgenic donor cells. Second, the CpG island methylation profile of the imprinted insulin-like growth factor receptor (IGF2R) gene was assessed in the lungs of the three dead transgenic kids and the normally produced kids using bisulfite sequencing PCR. In addition, the relative mRNA level of IGF2R was also determined by real-time PCR. Results showed that the IGF2R gene in the lungs of the dead cloned kids showed abnormal hypermethylation and higher mRNA expression levels than the control, indicating that aberrant DNA methylation reprogramming is one of the important factors in the death of transgenic cloned animals.


Subject(s)
Goats/genetics , Lactoferrin/genetics , Lung/metabolism , Receptor, IGF Type 2/genetics , Animals , Animals, Genetically Modified , Base Sequence , Cloning, Organism , DNA Methylation , Embryo Transfer , Female , Gene Expression , Genomic Imprinting , Humans , Microsatellite Repeats , Molecular Sequence Data , Receptor, IGF Type 2/metabolism , Sequence Analysis, DNA
10.
Genet Mol Res ; 13(4): 10518-22, 2014 Dec 12.
Article in English | MEDLINE | ID: mdl-25511035

ABSTRACT

To evaluate the population genetic diversity of the ovate pompano, we isolated and characterized 19 microsatellite markers using a (CA)13-enriched genomic library. Polymorphism was assessed in 30 individuals from a single population collected from the Daya Bay Aquaculture Center, Guangdong, China. The number of alleles per locus ranged from 2 to 18 with an average of 7.8. The observed and expected heterozygosities varied from 0.2667 to 1.000 and from 0.3960 to 0.9435, respectively. Sixteen of 19 loci conformed to Hardy-Weinberg equilibrium, and no significant linkage disequilibrium was detected between any locus pairs. Our study supplies candidate microsatellite markers that can be useful for studying the population genetic structure of ovate pompano.


Subject(s)
Fishes/genetics , Genetic Variation , Microsatellite Repeats/genetics , Alleles , Animals , China , Genetics, Population , Linkage Disequilibrium
11.
Genet Mol Res ; 13(3): 7965-78, 2014 Sep 29.
Article in English | MEDLINE | ID: mdl-25299112

ABSTRACT

The impact of complete and incomplete colonic obstruction on the short- and long-term outcomes of malignant colorectal cancer has not yet been elucidated. The aim of this study was to investigate whether there was a difference in the impacts of the 2 types of obstruction on the short- and long-term outcomes of colorectal resection. This study included 224 colorectal cancer patients (162 patients with incomplete obstruction and 62 with complete obstruction) with left-sided malignant colonic obstruction who underwent surgical therapy between February 2007 and September 2012. The short- and long-term outcomes of surgical therapy were analyzed. No significant difference was found between the 2 groups with regard to short-term outcomes such as the curative resection rate (80.86 vs 70.97%, P = 0.109), hospital stay time (24.20 ± 16.01 vs 24.19 ± 12.06, P = 0.999), and the overall and respective complications (32.72 vs 46.77%, P = 0.051). Furthermore, no significant difference was found between the 2 groups with regard to long-term outcomes including the 1-, 3-, and 5-year survival rates (P = 0.089), recurrence rates (P = 0.711), and recurrence-free survival rates (P = 0.440). The 2 types of obstruction, i.e., complete and incomplete left-sided malignant colonic obstruction, had no impact on the short- and long-term outcomes of colorectal resection. Similar therapeutic methods can be used for treating both types of obstruction.


Subject(s)
Colonic Neoplasms/complications , Intestinal Obstruction/etiology , Aged , Colonic Neoplasms/surgery , Female , Humans , Male , Middle Aged
12.
Am J Transplant ; 13(7): 1734-45, 2013 Jul.
Article in English | MEDLINE | ID: mdl-23714399

ABSTRACT

In a 24-month prospective, randomized, multicenter, open-label study, de novo liver transplant patients were randomized at 30 days to everolimus (EVR) + Reduced tacrolimus (TAC; n = 245), TAC Control (n = 243) or TAC Elimination (n = 231). Randomization to TAC Elimination was stopped prematurely due to a significantly higher rate of treated biopsy-proven acute rejection (tBPAR). The incidence of the primary efficacy endpoint, composite efficacy failure rate of tBPAR, graft loss or death postrandomization was similar with EVR + Reduced TAC (10.3%) or TAC Control (12.5%) at month 24 (difference -2.2%, 97.5% confidence interval [CI] -8.8%, 4.4%). BPAR was less frequent in the EVR + Reduced TAC group (6.1% vs. 13.3% in TAC Control, p = 0.010). Adjusted change in estimated glomerular filtration rate (eGFR) from randomization to month 24 was superior with EVR + Reduced TAC versus TAC Control: difference 6.7 mL/min/1.73 m(2) (97.5% CI 1.9, 11.4 mL/min/1.73 m(2), p = 0.002). Among patients who remained on treatment, mean (SD) eGFR at month 24 was 77.6 (26.5) mL/min/1.73 m(2) in the EVR + Reduced TAC group and 66.1 (19.3) mL/min/1.73 m(2) in the TAC Control group (p < 0.001). Study medication was discontinued due to adverse events in 28.6% of EVR + Reduced TAC and 18.2% of TAC Control patients. Early introduction of everolimus with reduced-exposure tacrolimus at 1 month after liver transplantation provided a significant and clinically relevant benefit for renal function at 2 years posttransplant.


Subject(s)
Glomerular Filtration Rate/physiology , Graft Rejection/drug therapy , Kidney/physiopathology , Liver Transplantation , Sirolimus/analogs & derivatives , Adolescent , Adult , Aged , Antineoplastic Agents , Dose-Response Relationship, Drug , Europe/epidemiology , Everolimus , Female , Follow-Up Studies , Glomerular Filtration Rate/drug effects , Graft Rejection/epidemiology , Graft Survival , Humans , Immunosuppressive Agents/therapeutic use , Incidence , Kidney/drug effects , Male , Middle Aged , North America/epidemiology , Prospective Studies , Sirolimus/administration & dosage , South America/epidemiology , Treatment Outcome , Young Adult
13.
Genet Mol Res ; 12(1): 312-8, 2013 Feb 04.
Article in English | MEDLINE | ID: mdl-23408418

ABSTRACT

The methylation of tumor suppressor genes has been shown to be involved in many human cancers. 5-Aza-2'-deoxycytidine (5-Aza-CdR) can reactivate the expression of methylated tumor suppressor genes. In our study, 2 human cervical cancer cell lines, HeLa and SiHa, were treated with different concentrations (20, 10, 5, and 2.5 µM) of 5-Aza-CdR for 24, 48, and 72 h. After incubation, cells were analyzed by 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide assay and flow cytometry. The expression of RASSF1A and APAF-1 was detected by RT-PCR. 5-Aza-CdR inhibited the growth of HeLa and SiHa cells at different concentrations. The strongest inhibition and apoptosis rates were obtained after incubation for 72 h (5.63 ± 1.38 and 8.24 ± 2.40%, respectively). No significant difference in the expression of RASSF1A was found upon drug treatment, while APAF-1 expression increased in HeLa cells after treatment (0.790 ± 0.056%). Our results suggest that the tumor-suppressive effect of 5-Aza-CdR may result from the reactivation of silenced APAF-1 through demethylation.


Subject(s)
Apoptosis/drug effects , Apoptosis/genetics , Azacitidine/analogs & derivatives , DNA Methylation/drug effects , Uterine Cervical Neoplasms/drug therapy , Uterine Cervical Neoplasms/genetics , Apoptotic Protease-Activating Factor 1/genetics , Azacitidine/pharmacology , Cell Growth Processes/drug effects , Cell Growth Processes/genetics , Cell Line, Tumor , Decitabine , Female , Gene Expression Regulation, Neoplastic/drug effects , HeLa Cells , Humans , Tumor Suppressor Proteins/genetics , Uterine Cervical Neoplasms/pathology
14.
Genet Mol Res ; 10(4): 3002-12, 2011 Oct 03.
Article in English | MEDLINE | ID: mdl-21968808

ABSTRACT

Cetuximab, a monoclonal antibody targeting epidermal growth factor receptor, has proven to be efficient in the treatment of metastatic colorectal cancer. We made a prospective study of the efficacy and toxicities of cetuximab-combination first-line (FOLFOX4) versus second/third-line (FOLFIRI) chemotherapy in 98 KRAS wild-type patients who had metastatic colorectal cancer. Wild-type KRAS had been identified by direct sequencing. Associations between clinical response/progression-free survival/overall survival/toxicities and cetuximab-combination chemotherapy timing were evaluated. The overall response rate was significantly higher for first-line treatment than for second/third-line treatment (relative risk = 1.707, 95% confidence interval = 1.121-2.598). Both progression-free survival and overall survival indicated significantly longer survival of first-line treatment than second/third-line treatment patients. This study is a validation of a molecular analysis of KRAS wild-type status for the prediction of response to cetuximab-combination chemotherapy for metastatic colorectal cancer patients; its predictive role was less prominent in the second/third-line than in the first-line treatment patients.


Subject(s)
Antibodies, Monoclonal/therapeutic use , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Colorectal Neoplasms/drug therapy , Liver Neoplasms/drug therapy , Lung Neoplasms/drug therapy , Proto-Oncogene Proteins/genetics , ras Proteins/genetics , Adult , Aged , Aged, 80 and over , Antibodies, Monoclonal/administration & dosage , Antibodies, Monoclonal, Humanized , Antineoplastic Combined Chemotherapy Protocols/administration & dosage , Camptothecin/administration & dosage , Camptothecin/analogs & derivatives , Camptothecin/therapeutic use , Cetuximab , Colorectal Neoplasms/genetics , Colorectal Neoplasms/mortality , Colorectal Neoplasms/pathology , DNA Mutational Analysis , Disease-Free Survival , Drug Administration Routes , Drug Administration Schedule , Drug-Related Side Effects and Adverse Reactions , ErbB Receptors/antagonists & inhibitors , Female , Fluorouracil/administration & dosage , Fluorouracil/therapeutic use , Humans , Leucovorin/administration & dosage , Leucovorin/therapeutic use , Liver Neoplasms/genetics , Liver Neoplasms/mortality , Liver Neoplasms/secondary , Lung Neoplasms/genetics , Lung Neoplasms/mortality , Lung Neoplasms/secondary , Male , Middle Aged , Mutation , Organoplatinum Compounds/administration & dosage , Organoplatinum Compounds/therapeutic use , Prospective Studies , Proto-Oncogene Proteins p21(ras)
15.
Integr Physiol Behav Sci ; 26(1): 5-17, 1991.
Article in English | MEDLINE | ID: mdl-2054298

ABSTRACT

The QT interval of the electrocardiogram, although often coordinated in an inverse relationship to heart rate, appears from the existing evidence to be regulated by mechanisms separate from those that govern heart rate. The purpose of this inquiry was to explore further the relationship of the two and to test other factors that may contribute to the regulation of QT. Heart rate and QT duration were measured in healthy human subjects during postural change and exercise. The data showed that, while coordinated in an inverse relationship under some circumstances, under others heart rate and QT were discordant, leading to the inference that there is no fixed linkage between the two. Previous work by the authors and other published studies have suggested that ventricular contractility may have more predictable association with QT shortening than do increases in heart rate. Observations of force of ventricular contraction (HI and IJ velocity) as reflected in ballisto-cardiographic tracings were made using each of 12 human subjects as the authors' own control. The data revealed a highly significant correlation between the velocity measures and QT duration (p less than 0.01) but not heart rate. These findings led to the conclusion that there is clearly not a fixed relationship between heart rate and QT interval and to the hypothesis that QT may more closely reflect the degree of cardiac contractility.


Subject(s)
Electrocardiography , Exercise Test , Heart Rate/physiology , Myocardial Contraction/physiology , Posture/physiology , Adult , Ballistocardiography , Female , Humans , Male , Middle Aged , Reference Values , Ventricular Function
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