Population pharmacokinetics and prophylactic anti-emetic efficacy of ramosetron in surgical patients.

AIMS: This study characterized the pharmacokinetics of ramosetron and compared prophylactic anti-emetic efficacy with that of ondansetron in a large population. METHODS: Fifty-eight patients consented to the pharmacokinetic analysis and were assigned randomly to receive 0.3, 0.45 or 0.6 mg ramosetron after induction of anaesthesia. Blood samples were acquired at preset intervals. Non-compartmental and population pharmacokinetic analyses were performed. In total, 1102 patients consented to the evaluation of prophylactic anti-emetic efficacy and were allocated randomly to receive 0.3 mg ramosetron or 4 mg ondansetron at the end of surgery. An additional 16 mg ondansetron were mixed in the intravenous patient-controlled analgesia pump of the ondansetron group. Post-operative nausea and vomiting (PONV) were evaluated 6, 24 and 48 h post-operatively using the Rhodes index of nausea, vomiting and retching (RINVR). Administration of rescue anti-emetics and adverse events were evaluated. RESULTS: The pharmacokinetic parameter estimates were V1 (l) = 5.12, V2 (l) = 108, CL (l⋅min(-1) ) = 0.08 + (59⋅age(-1) ) × 0.09, Q (l⋅min(-1) ) = 1.42. The incidences of PONV in the ramosetron and ondansetron groups were 77 (13.9%) and 113 (20.6%) and 44 (7.9%) and 66 (12.0%) at 24 and 48 h post-operatively, respectively (P = 0.004, 0.030). RINVR was significantly lower in the ramosetron than the ondansetron group 24 and 48 h post-operatively (P = 0.003, 0.025). Use of rescue anti-emetics and incidence of adverse events were comparable. CONCLUSIONS: A two compartment mammillary model was used to describe ramosetron pharmacokinetics. Prophylactic anti-emetic efficacy of ramosetron was significantly better 24 and 48 h post-operatively than that of ondansetron, particularly when the Apfel score was ≥ 3.

Performance evaluation of the TheraTyper-GJB2 assay for detection of GJB2 gene mutations.

Mutations in the GJB2 gene are the most common cause of congenital hearing loss in many populations. This study describes the development of a matrix-assisted laser desorption/ionization time-of-flight mass spectrometry-based minisequencing assay, TheraTyper-GJB2, for the detection of c.35delG, c.167delT, and c.235delC mutations in the GJB2 gene. This assay was evaluated for analytic performance, including detection limit, interference, cross-reactivity, and precision, using GJB2 reference standards prepared by site-directed mutagenesis of a molecular clone. The detection limit was as low as 0.040 ng of human genomic DNA per PCR. No cross-reactivity with bacteria and viruses and no negative effects of increased levels of various potential interfering substances was observed. A precision test involving repetitive analysis of 2400 replicates showed 99.9% agreement (2397 of 2,400) with 99.8% (95% CI, 99.7%-99.8%) sensitivity and 100.0% (95% CI, 99.3%-100.0%) specificity. TheraTyper-GJB2 and direct sequencing assays showed 100% concordance for detecting mutations in 1,113 clinical specimens. Overall, TheraTyper-GJB2 showed comparable performance for detecting GJB2 mutations in reference and clinical samples with that of direct sequencing, and easier interpretation of results for analysis of a large quantity of samples. Therefore, the TheraTyper-GJB2 assay will be practically useful for the diagnosis of GJB2 mutations associated with congenital hearing loss with faster, cheaper, more reliable, and high-throughput capability.

Multiplex detection of KRAS mutations by a matrix-assisted laser desorption/ionization-time of flight mass spectrometry assay.

OBJECTIVES: Mutations of the Kirsten rat sarcoma viral oncogene (KRAS) gene are known to be important in the pathogenesis of a variety of cancers. Patients with mutant KRAS tumors do not respond to epidermal growth factor receptor (EGFR) inhibitors and fail to benefit from adjuvant chemotherapy. Testing for KRAS mutations is now being recommended as a tailored therapeutic strategy prior to anti-EGFR treatment; however, the low sensitivity of direct sequencing frequently leads to failure of detection of KRAS mutations in clinical samples. DESIGN AND METHODS: We developed restriction fragment mass polymorphism (RFMP) assays, to detect KRAS mutations in codons 12, 13, and 61. We performed RFMP analysis for KRAS on DNA isolated from eight different KRAS mutant cell lines and 34 formalin-fixed paraffin-embedded (FFPE) lung cancer tissues. RESULTS: Overall, the RFMP assay was in good concordance with direct sequencing analysis in the detection of KRAS mutations. By using dilutions of KRAS mutant DNA in wild type DNA from mutation cell lines with a known KRAS status, we confirmed that the RFMP assay has a higher analytical sensitivity, requiring only 3% of cells in a sample to have mutant alleles, compared to direct sequencing, which had a detection threshold of ~25%. In the FFPE samples, RFMP successfully detected KRAS genotypes in codons 12, 13, and 61. CONCLUSION: The RFMP might be efficiently applicable for the detection of KRAS mutations in a clinical setting, particularly for tumor samples containing abundant non-neoplastic cells.

Comparison of digene hybrid capture 2, GeneMatrix PapilloScreen, and a PCR sequencing assay in detecting high-risk and probable high-risk oncogenic HPV genotypes in specimens from Korean women.

Most cervical cancers are caused by 15 high-risk (HR) and three probable high-risk (pHR) oncogenic types of human papillomavirus (HPV). However, current commercial HR HPV screening test products do not include pHR HPV genotypes. Recently, PapilloScreen has been developed to detect the 15 HR and three pHR HPV types. In this study, we evaluated the concordance levels and clinical performance of Hybrid Capture 2 (HC2), PapilloScreen, and a PCR sequencing assay in detecting HR and pHR HPV. The PapilloScreen (96.8 %) and PCR sequencing assay (96.8 %) demonstrated higher sensitivity than HC2 (80.7 %) for detecting HR and pHR HPV. The three assays showed similar specificities and positive or negative predictive values. The concordance levels were 86.5 % (κ = 0.68) and 86.5 % (κ = 0.67) between HC2 and PapilloScreen and between HC2 and PCR sequencing, respectively. A near-perfect concordance was observed between PapilloScreen and PCR sequencing (97.8 %, κ = 0.95). Overall, the agreement between the three assays suggests that the results obtained by the HC2 assay are more often discordant (12.6 %) than the PCR-based tests. In conclusion, PapilloScreen is highly sensitive for detecting high-grade CIN or cervical cancer. The PapilloScreen assay should be considered an accurate and sensitive method for detecting HR and pHR HPV infections and an epidemiological tool for prevalence studies as well as early diagnosis and intervention in HR and pHR HPV infections.

Sedation for interventional gastrointestinal endoscopic procedures: are we overlooking the "pain"?

BACKGROUND: Although interventional gastrointestinal (GI) endoscopic procedures are known to cause greater pain and discomfort than diagnostic procedures, the efficacy of adequate pain control or the difference in pain and amount of analgesic required according to type of intervention is not well known. This study was done to investigate the safety and efficacy of combining fentanyl with propofol for interventional GI endoscopic procedures and determine whether this method is superior to propofol monosedation. METHODS: The data of 810 patients that underwent interventional GI endoscopic procedures under sedation with either propofol alone (Group P, n = 499) or propofol/fentanyl (Group PF, n = 311) at a single tertiary-care hospital between May 2012 and December 2012 were retrospectively reviewed. Rates of respiratory and cardiovascular events, propofol and fentanyl requirements, and risk factors of respiratory events of the two groups were analyzed. RESULTS: The incidence of respiratory events (P = 0.001), number of cases in which the procedure had to be interrupted for assisted mask bagging (P = 0.044), and propofol infusion rates were significantly lower in Group PF compared to Group P (P < 0.0001). The amount of fentanyl required for diagnostic procedures was significantly lower than that for interventional procedures (P < 0.001). Patients of Group PF showed a lower risk of developing respiratory events compared to Group P (OR 0.224, 95 % CI 0.069­0.724). CONCLUSIONS: Combining fentanyl with propofol seems to reduce the risk of respiratory events compared with propofol monosedation during GI endoscopic procedures by providing effective analgesia.

Comparison of the clinical performance of restriction fragment mass polymorphism (RFMP) and Roche linear array HPV test assays for HPV detection and genotyping.

BACKGROUND: The need for accurate genotyping of human papillomavirus (HPV) infections is becoming increasingly important as HPV is the primary cause of cervical cancer worldwide. The matrix-assisted laser desorption ionization time-of-flight mass spectrometry-based restriction fragment mass polymorphism (RFMP) assay provides accurate, broad-spectrum, high-throughput genotyping of HPV. OBJECTIVES: We evaluated the clinical performance of the RFMP assay compared to a commercially available Roche linear array HPV genotyping test (LA) for detecting and genotyping of HPV. STUDY DESIGN: The RFMP assay and the LA were compared for detecting and genotyping HPV among a cohort of 244 liquid-based cytology samples. RESULTS: Overall, 216 specimens (93.1%, κ = 0.86) generated concordant results for the presence or absence of high-risk HPV (HR-HPV) by the two assays. The RFMP assay and the LA assay generated concordant, compatible, and discordant genotyping results for 79.3, 9.9, and 10.8%, respectively. The diagnostic sensitivity and specificity of RFMP and LA for the cervical lesions of squamous cell carcinoma (SCC) were similar, at 92.9 and 85.0% (RFMP) and 92.9 and 83.8% (LA), respectively. In addition, the odds ratio for SCC with HR-HPV positivity estimated by the RFMP assay (73.7, 95% CI: 8.9-3173.3) was higher than the LA assay (67.0, 95% CI: 8.2-2887.0). CONCLUSIONS: The RFMP and the LA assays were highly comparable with regard to detection and genotyping analysis of HPV. The sensitivity and specificity of RFMP assay for the detection of HR-HPV in various levels of cervical lesions seems to be valuable in the monitoring of HPV-associated cervical cancer.

Association of the miR-146aC>G, miR-149T>C, miR-196a2T>C, and miR-499A>G polymorphisms with gastric cancer risk and survival in the Korean population.

We investigated whether four common microRNA polymorphisms (miR-146aC>G [rs2910164], miR-149T>C [rs2292832], miR-196a2T>C [rs11614913], and miR-499A>G [rs3746444]) are associated with the susceptibility and prognosis of gastric cancer in the Korean population. The four microRNA single-nucleotide polymorphisms (SNPs) were identified in a case-control study (461 patients; 447 controls) by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) analysis in the Korean population. When patients were stratified into diffuse and intestinal-type gastric cancer groups, subjects with the miR-499AG and AG + GG genotypes had reduced adjusted odds ratios (AORs) for diffuse-type gastric cancer (AOR = 0.54 with 95% confidence interval [CI] = 0.31-0.97; AOR = 0.57 with 95% CI = 0.33-0.97). In the stratified analyses for gastric cancer risk, the miR-146aGG and CG + GG genotypes were associated with increased risk of gastric cancers among the non-smokers, whereas the miR-149TC and TC + CC genotypes showed lower risk of gastric cancer in males. The miR-196a2CC genotype was associated with elevated gastric cancer risk among females. For gastric cancer prognosis, intestinal-type gastric cancer patients with miR-146aCG + GG genotypes had significantly higher survival rates (log-rank P = 0.030) than patients with the CC genotype, and patients with the miR-499AA genotype had significantly increased survival rates compared to patients with the AG + GG genotypes (log-rank P = 0.013). When miR-146aCG + GG and miR-499AA genotypes were combined, the survival rate of intestinal-type gastric cancer patients was elevated (log-rank P < 0.001). No association was found between gastric or diffuse-type cancer prognosis and other miRNAs. Our data demonstrate that specific miRNA SNPs are associated with gastric cancer susceptibility (miR-499A>G) and prognosis (miR-146aC>G and miR-499A>G) in the Korean population depending on gastric cancer type.

Association between common genetic variants of α2A-, α2B-, and α2C-adrenergic receptors and ischemic stroke.

BACKGROUND: The alpha2-adrenergic receptor (α2-AR) mediates physiological responses to endogenous catecholamine, and genetic variants of α2-AR may predispose to clinical vascular diseases. We evaluated whether common genetic variants of each three subtype of alpha2-adrenergic receptor (ADRA2A, ADRA2B, and ADRA2C) were associated with ischemic stroke. METHODS: A total of 616 patients with ischemic stroke and 512 controls were genotyped for the ADRA2A 1780G>A, ADRA2B 301-303 I/D, and ADRA2C 322-325 I/D polymorphisms. Logistic regression analyses, adjusting for multiple comparisons, were used to determine the association between the minor allele of each of three ADRA2 genes and the risk of ischemic stroke and pathophysiological subtypes. RESULTS: The ADRA2B 301-303 D allele was more prevalent in the stroke group, compared to controls (DD vs. II, OR: 1.78, 95% CI: 1.18-2.69; recessive, OR: 1.55, 95% CI: 1.06-2.26). A subgroup analysis revealed that this association was found only in the small vessel diseases (SVD) type (DD vs. II, OR: 1.92, 95% CI: 1.11-3.33). The ADRA2A and ADRA2C polymorphisms did not contribute to an increased risk of ischemic stroke or any pathophysiological subtype. CONCLUSIONS: The ADRA2B 301-303 D allele confers an increased risk of overall ischemic stroke and SVD subtype.

Association study of microRNA polymorphisms with hepatocellular carcinoma in Korean population.

BACKGROUND: Recent studies have suggested that common genetic polymorphisms alter the processing of microRNA (miRNA) and may be associated with the development and progression of cancer. PATIENTS AND METHODS: The association of miRNA polymorphisms with HCC survival was analyzed in 159 HCC patients and 201 controls by the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) method. RESULTS: The risk of HCC was significantly lower for the miR-499A>G, AG+GG in HCC patients (AOR=0.603, 95% CI=0.370-0.984) and hepatitis B virus (HBV)-related HCC patients (AOR=0.561, 95% CI 0.331-0.950). In addition, the risk of HCC was significantly lower for the miR-149C>T, CT and CT+CC in HCC patients (CT; AOR=0.542, 95% CI=0.332-0.886, CT+CC; AOR=0.536, 95% CI=0.335-0.858) and HBV-related HCC patients (CT: AOR=0.510, 95% CI 0.305-0.854, CT+CC: AOR=0.496, 95% CI 0.302-0.813). The miR-149C>T polymorphism was also associated with survival rate of HCC patients in OKUDA II stage. CONCLUSIONS: miR-149C>T and miR-499A>G were associated with HBV-related HCC. Further studies on larger populations will need to be conducted to confirm these results.

Polymorphisms of platelet ADP receptor P2RY12 in the risk of venous thromboembolism in the Korean population.

Although it was thought that platelets did not play a significant role in the pathogenesis of venous thromboembolism (VTE), several studies demonstrated that a marked activation of platelets occurs in patients with VTE. We carried out a case-control study to investigate the effect of the T744C P2RY12 polymorphism on the risk of VTE in the Korean population. We enrolled 154 consecutive patients with VTE and 415 healthy controls. Genotype frequencies for patients with TT, TC, and CC were 71.4%, 24.7%, and 3.9% and in the controls, 68.2%, 30.1%, and 1.7%, respectively. T744C P2RY12 polymorphism did not significantly affect the risk of VTE. Our study shows that T744C P2RY12 polymorphism did not significantly affect the risk of VTE in the Korean population.

Association of the miR-146aC>G, 149C>T, 196a2C>T, and 499A>G polymorphisms with colorectal cancer in the Korean population.

MicroRNAs (miRNAs) are small, 18- to 22-nucleotide non-coding RNAs that regulate target gene expression. Although recent studies focused on various diseases that harbor the miR-146aC>G (rs2910164), 149C>T (rs2292832), 196a2C>T (rs11614913), and 499A>G (rs3746444) polymorphisms, the role of miRNA genetic variants in colorectal cancer is still unknown. The present study aimed to evaluate the role of four miRNA polymorphisms in patients with colorectal cancer. We enrolled 446 colorectal cancer patients and 502 control subjects from the Korean population. We found a significantly increased colorectal cancer risk with the miR-196a2CC genotype compared with the TT/CT genotype (AOR = 1.50; 95% CI = 1.11-2.04; P = 0.01; FDR-P = 0.04). In the stratified analyses, we observed both weak and strong association data. We found stronger associations of the miR-196a2 variants in the non-diabetic and rectal cancer groups than other stratified groups. Our data suggest that the miRNA variants could affect the development of colorectal cancer in the Korean population.

Sudden asystole due to trigeminocardiac reflex during transsphenoidal surgery for pituitary tumor.

BACKGROUND: A sudden attack of an asystolic phenomenon is an extremely rare event during transsphenoidal surgery (TSS). It may be caused by an extreme type of trigeminocardiac reflex (TCR) during the manipulation of the trigeminal nerve or its innervated structures. CASE DESCRIPTION: We report two cases of sudden asystole and a case of severe bradycardia due to TCR during TSS. All patients were managed successfully by cessation of the surgical manipulation or with the injection of an anticholinergic agent. CONCLUSIONS: Although TCR occurs rarely and usually is self-limiting, surgeons should be cautious of its occurrence, especially when manipulating the cavernous sinus during TSS. This allows the early detection and appropriate treatment of this manifestation. Stopping the surgical procedure as soon as TCR occurs is likely to normalize the vital parameters. In addition, if further manipulations are inevitable, the administration of anticholinergic medication should be considered cautiously to improve surgical outcomes.

Association between VEGF polymorphisms and homocysteine levels in patients with ischemic stroke and silent brain infarction.

BACKGROUND AND PURPOSE: Vascular endothelial growth factor (VEGF) plays a role in atherosclerosis-related diseases such as cerebrovascular or cardiovascular diseases. However, the effect of VEGF -2578C>A, -1154G>A, -634G>C, and 936C>T polymorphisms on the susceptibility to stroke and silent brain infarction has not been reported. METHODS: Using polymerase chain reaction-amplified DNA, VEGF polymorphisms were analyzed in 615 patients with ischemic stroke, 376 patients with silent brain infarction, and 494 control subjects. RESULTS: The AA and CC+CA (C allele bearing) genotype frequencies of the -2578C>A polymorphism and the CT+TT (T allele-bearing) genotype frequency of the 936C>T polymorphism were significantly different between the stroke and control groups (false discovery rate-adjusted probability values of 0.016, 0.044, and 0.044, respectively). When stratified by the size of the occluded vessel, the VEGF polymorphisms were associated with patients with multiple small-artery occlusions. Several haplotypes of the VEGF polymorphisms were significantly different between the control and stroke groups. With respect to silent brain infarction, the difference in the frequency of the -634G>C polymorphism between the GC+CC (C allele-bearing) genotype and the controls was marginally significant (false discovery rate-adjusted probability value of 0.056). On the other hand, the -634G>C and 936C>T polymorphisms were associated with plasma homocysteine levels of patients with multiple or single small-artery occlusions, respectively. CONCLUSIONS: This study suggests that VEGF polymorphisms and haplotypes are possible genetic determinants for the risk of ischemic stroke, particularly in patients with multiple small-artery occlusions. However, VEGF polymorphisms had only a weak association with plasma homocysteine levels in the Korean population.

Age-specific eNOS polymorphisms in moyamoya disease.

OBJECTIVE: We conducted a case-control study to investigate whether polymorphisms in eNOS are related to the age-specific onset of moyamoya disease. MATERIALS AND METHODS: Ninety-three Korean patients [mean age, 23.0 ± 16.1 years; 59 female (63.4%) and 34 male (36.6%)] with moyamoya disease were consecutively recruited for this study. Three hundred twenty-eight healthy subjects [mean age, 27.7 ± 16.2 years; 217 female (66.2%), 111 male (33.8%)] were consecutively included in the control group. The subjects were divided into pediatric (< 20 years) and adult (≥ 20 years) groups. We further divided the moyamoya group into ischemic and hemorrhagic groups based on clinical and MRI findings. The frequencies and distributions of four eNOS polymorphisms (eNOS -922A>G, -786T>C, 4a4b, and 894G>T) were assessed in pediatric and adult patients with moyamoya disease and compared to the frequencies and distribution in the control group. RESULTS: No differences in eNOS polymorphisms were observed between control and moyamoya disease group. However, we found that the 4a4b sequences was less frequent in the adult group (p = 0.029). Compared to the control group, there were differences in the haplotype distribution of the study group, specifically the A-4b-G haplotype, which was seen more frequently in the adult patient group. CONCLUSION: Our results suggest that pediatric and adult-onset moyamoya disease have different genetic backgrounds. These genetic differences can affect age-specific clinical characteristics, such as cerebral ischemia and hemorrhage.

Association between kinase insert domain-containing receptor gene polymorphism and haplotypes and ischemic stroke.

BACKGROUND: Kinase insert domain-containing receptor (KDR), a type 2 vascular endothelial growth factor receptor, plays a crucial role in angiogenesis and vascular integrity of blood vessels. We evaluated whether single nucleotide polymorphisms (SNPs) and haplotype of kinase insert domain-containing receptor (KDR) are associated with increased risk of ischemic stroke in the Korean population. METHODS: Totals of 501 patients with ischemic stroke and 478 controls were screened for the KDR -604T>C, +1192G>A, and +1719A>T SNPs. Subgroup analysis was performed to determine whether the effect of KDR polymorphism is specific to certain etiological subtypes of ischemic stroke. In addition, haplotype frequencies of these three SNPs were analyzed in stroke patients and controls. RESULTS: The SNP +1719T allele was associated with risk of ischemic stroke in a dose-dependent manner (TT vs. AA: adjusted OR: 1.90, 95% CIs: 1.29-2.81, p=0.001 and false discovery rate (FDR)=0.003). Subgroup analysis showed that the SNP +1719T allele had a slight but significant association with small vessel disease type (TT vs. AA: adjusted OR: 1.91, 95% CIs: 1.11-3.29, p=0.02). There was no association between SNP -604 and SNP +1192 and ischemic stroke risk. In haplotype analysis, the T-G-T (-604/+1192/+1719), T-A-T, and C-G-T haplotypes increased the relative risk of ischemic stroke. CONCLUSIONS: The KDR +1719A>T polymorphism and its haplotypes are possible genetic determinants for the risk of ischemic stroke.

Prognostic significance of microRNA gene polymorphisms in patients with surgically resected colorectal cancer.

MicroRNAs (miRNAs) are small 19- to 22-nucleotide sequences of RNA that participate in the regulation of cell differentiation, cell cycle progression and apoptosis. Although single-nucleotide polymorphisms (SNPs) in miRNA regions are considered unlikely to be functionally important, nucleotide variations within the sequences of primary (pri)- or precursor (pre)-miRNAs may affect miRNA processing and ultimately result in the modification of miRNA expression. The aim of this study was to investigate associations between four SNPs in pre-miRNA genes and the survival of colorectal cancer patients. A total of 407 colorectal patients were consecutively enrolled. DNA was extracted from blood specimens, and the hsa-mir-146aC>G, hsa-mir-149C>T, hsa-mir-196a2C>T and hsa-mir-499A>G polymorphisms were genotyped by PCR-RFLP. We were unable to identify independent prognostic SNPs for colorectal cancer. However, the heterozygous TC genotype of the 196a2C>T polymorphism was a significant risk factor for the overall survival of rectal cancer patients (HR=3.554, 95% CI 1.296-9.747, p=0.014). Further large-population studies are warranted to define the 196a2C>T polymorphism as a prognostic factor of rectal cancer.

Pregabalin and gabapentin inhibit substance P-induced NF-kappaB activation in neuroblastoma and glioma cells.

Pregabalin and gabapentin are lipophilic amino acid derivatives of gamma-amino butyric acid that show anticonvulsant and analgesic activity against neuropathic pain. In this study, we investigated their actions on substance P-induced NF-kappaB activation in human neuroblastoma and rat glioma cells. Pregabalin and gabapentin decreased substance P-induced NF-kappaB activation in these cells. These drugs also inhibited NF-kappaB activation in rat spinal dorsal root ganglia cells pre-treated in vitro with substance P. These results suggest a previously undefined role of pregabalin and gabapentin in the regulation of inflammation-related intracellular signaling in both neuronal and glial cells.