Effects of CYP2D6 Genetic Polymorphism and Drug Interaction on the Metabolism of Dacomitinib.

We aim to study the effects of CYP2D6 variants and drug-drug interaction on the metabolism of dacomitinib. CYP2D6 variants were incubated with 25-1000 µM dacomitinib for 40 min at 37 °C, and the reaction was terminated by cooling to -80 °C immediately. For an in vivo experiment, 18 male Sprague-Dawley rats were randomly divided into three groups (n = 6): a single dose of 5 mg/kg dacomitinib (group A), a single dose of 6 mg/kg trazodone (group B), and a combined group (group C). Processed samples were analyzed by ultraperformance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS.) The relative clearance of dacomitinib was reduced for most of the variants. Moreover, the inhibitory potency of classic CYP inhibitors on dacomitinib metabolism was significantly different among the main subtypes of CYP2D6. Interestingly, compared with gefitinib, even the same CYP2D6 variants showed significant differences in metabolic activity, suggesting that the activity of CYP2D6 has strong variability. In addition, the interaction between trazodone and dacomitinib was determined both in vitro and in vivo. When dacomitinib was given in combination with trazodone, the blood exposure to these two drugs increased remarkably. The mechanistic study revealed that the interaction followed the noncompetitive inhibition. We demonstrated that the activity of CYP2D6 variants to metabolize dacomitinib was significantly reduced. In combination with the CYP2D6 inhibitor, the degree of activity inhibition of different variants obviously differed. When trazodone and dacomitinib were used in combination, the body exposure to the two drugs increased significantly. This study provides data for the precise use of dacomitinib in clinical settings.

Effects of CYP2C9*3 and *13 alleles on the pharmacokinetics and pharmacodynamics of glipizide in healthy Korean subjects.

Glipizide is a second-generation sulfonylurea antidiabetic drug. It is principally metabolized to inactive metabolites by genetically polymorphic CYP2C9 enzyme. In this study, we investigated the effects of CYP2C9*3 and *13 variant alleles on the pharmacokinetics and pharmacodynamics of glipizide. Twenty-four healthy Korean volunteers (11 subjects with CYP2C9*1/*1, 8 subjects with CYP2C9*1/*3, and 5 subjects with CYP2C9*1/*13) were recruited for this study. They were administered a single oral dose of glipizide 5 mg. The plasma concentration of glipizide was quantified for pharmacokinetic analysis and plasma glucose and insulin concentrations were measured as pharmacodynamic parameters. The results represented that CYP2C9*3 and *13 alleles significantly affected the pharmacokinetics of glipizide. In subjects with CYP2C9*1/*3 and CYP2C9*1/*13 genotypes, the mean AUC0-∞ were increased by 44.8% and 58.2%, respectively (both P < 0.001), compared to those of subjects with CYP2C9*1/*1 genotype, while effects of glipizide on plasma glucose and insulin levels were not significantly different between CYP2C9 genotype groups. In conclusion, individuals carrying the defective CYP2C9*3 and CYP2C9*13 alleles have markedly elevated plasma concentrations of glipizide compared with CYP2C9*1/*1 wild-type.

PBPK Analysis to Study the Impact of Genetic Polymorphism of NAT2 on Drug-Drug Interaction Potential of Isoniazid.

PURPOSE: Isoniazid (INH) is prescribed both for the prophylaxis as well as the treatment of tuberculosis. It is primarily metabolized through acetylation by a highly polymorphic enzyme, N-acetyl transferase 2 (NAT2), owing to which significant variable systemic drug levels have been reported among slow and rapid acetylators. Furthermore, many drugs, like phenytoin, diazepam, triazolam, etc., are known to show toxic manifestation when co-administered with INH and it happens prominently among slow acetylators. Additionally, it is revealed in in vitro inhibition studies that INH carries noteworthy potential to inhibit CYP2C19 and CYP3A4 enzymes. However, CYP inhibitory effect of INH gets masked by opposite enzyme-inducing effect of rifampicin, when used in combination. Thus, distinct objective of this study was to fill the knowledge gaps related to gene-drug-drug interactions (DDI) potential of INH when given alone for prophylactic purpose. METHODS: Whole body-PBPK models of INH were developed and verified for both slow and fast acetylators. The same were then utilized to carry out prospective DDI studies with CYP2C19 and CYP3A4 substrates in both acetylator types. RESULTS: The results highlighted likelihood of significant higher blood levels of CYP2C19 and CYP3A4 substrate drugs in subjects receiving INH pre-treatment. It was also re-established that interaction was more likely in slow acetylators, as compared to rapid acetylators. CONCLUSION: The novel outcome of the present study is the indication that prescribers should give careful consideration while advising CYP2C19 and CYP3A4 substrate drugs to subjects who are on prophylaxis INH therapy, and are slow to metabolic acetylation.

Differential Interactions of Selected Phytocannabinoids with Human CYP2D6 Polymorphisms.

Cytochrome P450 2D6 (CYP2D6) is primarily expressed in the liver and in the central nervous system. It is known to be highly polymorphic in nature. It metabolizes several endogenous substrates such as anandamide (AEA). Concomitantly, it is involved in phase 1 metabolism of several antidepressants, antipsychotics, and other drugs. Research in the field of phytocannabinoids (pCBs) has recently accelerated owing to their legalization and increasing medicinal use for pain and inflammation. The primary component of cannabis is THC, which is well-known for its psychotropic effects. Since CYP2D6 is an important brain and liver P450 and is known to be inhibited by CBD, we investigated the interactions of four important highly prevalent CYP2D6 polymorphisms with selected phytocannabinoids (CBD, THC, CBDV, THCV, CBN, CBG, CBC, ß-carophyllene) that are rapidly gaining popularity. We show that there is differential binding of CYP2D6*17 to pCBs as compared to WT CYP2D6. We also perform a more detailed comparison of WT and *17 CYP2D6, which reveals the possible regulation of AEA metabolism by CBD. Furthermore, we use molecular dynamics to delineate the mechanism of this binding, inhibition, and regulation. Taken together, we have found that the interactions of CYP2D6 with pCBs vary by polymorphism and by specific pCB class.

Cytokine-based Cancer Immunotherapy: Challenges and Opportunities for IL-10.

Cancer immunotherapy is an evolving field of research. Cytokines have been conceptualized as an anticancer therapy for longer than most other cancer immunotherapy modalities. Yet, to date, only two cytokines are FDA-approved: IFN-α and IL-2. Despite the initial breakthrough, both agents have been superseded by other, more efficacious agents such as immune checkpoint inhibitors. Several issues persist with cytokine-based cancer therapies; these are broadly categorised into a) high toxicity and b) low efficacy. Despite the only moderate benefits with early cytokine-based cancer therapies, advances in molecular engineering, genomics, and molecular analysis hold promise to optimise and reinstate cytokine-based therapies in future clinical practice. This review considers five important concepts for the successful clinical application of cytokine-based cancer therapies including: (i) improving pharmacokinetics and pharmacodynamics, (ii) improving local administration strategies, (iii) understanding context-dependent interactions in the tumour-microenvironment, (iv) elucidating the role of genetic polymorphisms, and (v) optimising combination therapies. IL-10 has been the focus of attention in recent years and is discussed herein as an example.

Pharmacokinetics, Tolerability and Pharmacogenetics of DA-8031 After Multiple Ascending Doses in Healthy Male Subjects.

PURPOSE: DA-8031 is a novel selective serotonin reuptake inhibitor for the treatment of premature ejaculation. This study investigated the pharmacokinetics, safety and tolerability of multiple oral doses of DA-8031. In addition, a genetic analysis was explored to evaluate the effect of genetic polymorphisms on the pharmacokinetics of DA-8031. SUBJECTS AND METHODS: A dose block-randomized, double-blind, placebo-controlled study was conducted in 3 dose groups with 20, 30 and 40 mg of DA-8031. Healthy male subjects were randomized to DA-8031 or placebo at a 4:1 ratio in each dose group of 10 subjects by oral administration once daily for 7 consecutive days. Serial blood and urine samples were collected for the pharmacokinetic evaluation, and the pharmacokinetic-related genes were analyzed by DMETTM plus. A safety evaluation was conducted including adverse events (AEs) monitoring and 12-lead electrocardiogram (ECG). RESULTS: The plasma DA-8031 concentration reached the maximum concentration (Cmax) in 2.2 to 3.0 h and was eliminated with a mean half-life of 25.5 to 26.7 h at steady state. The accumulation index of DA-8031 ranged 2.3 to 2.8. The systemic exposure of DA-8031 of the CYP2D6 intermediate metabolizer (IM) was significantly higher compared to the CYP2D6 poor metabolizer (PM). There were no clinically significant QTc interval changes, and all the adverse events were mild. CONCLUSION: After multiple oral doses of DA-8031 20, 30, and 40 mg in this study, the systemic exposure of DA-8031 increased in a more than dose-proportional manner with the increasing doses, and DA-8031 was generally well tolerated. In addition, the genetic polymorphisms of CYP2D6 have an impact on the pharmacokinetics of DA-8031.

A meta-analysis of effects of CYP2C9 and CYP2C19 polymorphisms on phenytoin pharmacokinetic parameters.

Aim: Phenytoin is metabolized through CYP2C9 and CYP2C19. Polymorphisms of CYP2C9 and CYP2C19 may increase plasma concentration and side effects. Materials & methods: Systematic review and meta-analysis were performed to evaluate the effects of CYP2C9 and CYP2C19 polymorphism on pharmacokinetic parameters. PubMed, Science Direct, Cochrane library, and Thai databases were systematically searched. Results: Eight observational studies, comprising a total of 633 patients were included. Michaelis-Menten constant was significantly higher in the polymorphism of CYP2C9IM/CYP2C19EM and CYP2C9IM/CYP2C19IM groups as compared with the control groups (CYP2C9EM/CYP2C19EM) at 2.16 and 1.55 mg/l (p < 0.00001, p < 0.0001). The maximum rate of action was significantly lower in the control groups as compared with the polymorphism of CYP2C9IM/CYP2C19EM and CYP2C9IM/CYP2C19IM groups at 3.10 and 3.53 mg/kg/day (p = 0.00001, <0.0001). Conclusion: The dosage regimen for patients in the CYP2C9IM group to achieve phenytoin therapeutic levels was 2.1-3.4 mg/kg/day.

Expression of Vitamin D Receptor and Vitamin D Receptor Gene Polymorphisms (BsmI, FokI, and TaqI) in Patients with Pterygium / Expressão do gene do receptor da vitamina D e de seus polimorfismos (BsmI, FokI e TaqI) em pacientes com pterígio

ABSTRACT Purpose: This study aimed to determine the role of vitamin D receptor in the pathogenesis of pterygium. The vitamin D receptor eexpression levels in pterygium tissue, blood vitamin D levels, and frequency of selected vitamin D receptor gene polymorphisms (BsmI, FokI, and TaqI) were compared between patients with pterygium and healthy participants. Methods: The study included patients with pterygiumeee (n=50) and healthy volunteers (n=50). The serum vitamin D levels were measured for both groups. Immunohistochemical staining for vitamin D receptor ewas performed on sections obtained from the pterygium and adjacent healthy conjunctival tissues of the same individuals. The genomic existence of vitamin D receptor epolymorphisms (BsmI, FokI, and TaqI) were analyzed in DNA obtained from venous blood of participants using polymerase chain reaction and restriction fragment length polymorphism methods. Results: There was no difference found between the serum vitamin D levels of patients with pterygium and healthy controls. However, tissue expression of vitamin D receptor was higher in the pterygium endothelial cells of micro-vessels (p=0.002), subepithelial stromal (p=0.04), and intravascular inflammatory cells (p=0.0001), in comparison with the adjacent healthy conjunctival tissue. Moreover, while the BBtt haplotype was 2-fold higher, the bbTt haplotype was 2.5-fold lower, and the BbTT haplotype was 2.25-fold lower in the control group than in the pterygium group (p<0.001). Conclusions: Vitamin D serum levels did not differ between the healthy and pterygium groups. Vitamin D receptor expression was increased in the pterygium tissue versus the adjacent healthy tissue. However, vitamin D receptor polymorphism analysis in patients with pterygium did not reveal any significant difference in BsmI, FokI, or TaqI polymorphisms in comparison with the healthy volunteers.(AU)

RESUMO Objetivo: Determinar o papel do receptor da vitamina D na patogênese do pterígio. Os níveis de expressão do receptor da vitamina D no tecido do pterígio, os níveis sanguíneos de vitamina D e a frequência de alguns polimorfismos do gene do receptor da vitamina D (BsmI, FokI e TaqI) foram comparados entre pacientes com pterígio e participantes saudáveis. Métodos: Foram incluídos pacientes com pterígio (n=50) e voluntários saudáveis (n=50). Os níveis séricos de vitamina D foram medidos em ambos os grupos. Foi feita uma coloração imuno-histoquímica para o receptor da vitamina D em cortes obtidos do pterígio e dos tecidos conjuntivais saudáveis adjacentes dos mesmos indivíduos. A existência de polimorfismos do receptor da vitamina D (BsmI, FokI e TaqI) no genoma foi analisada em DNA obtido do sangue venoso dos participantes, usando métodos de Polymerase chain reaction (PCR) e RFLP. Resultados: Não foi observada nenhuma diferença entre os níveis séricos de vitamina D dos pacientes com pterígio e os dos controles saudáveis. Entretanto, a expressão tissular do receptor da vitamina D foi maior nas células endoteliais dos microvasos do pterígio (p=0,002), nas células estromais sub-epiteliais (p=0,04) e nas células inflamatórias intravasculares (p=0,0001), quando comparada à expressão no tecido conjuntival saudável adjacente. Além disso, embora o haplótipo BBtt tenha sido duas vezes mais frequente, o haplótipo bbTt foi 2,5 vezes menos frequente e o haplótipo BbTT foi 2,25 vezes menos frequente no grupo de controle do que no grupo com pterígio (p<0,001). Conclusões: Os níveis séricos de vitamina D não apresentaram diferenças entre o grupo de pessoas saudáveis e o com pterígio. A expressão do receptor da vitamina D mostrou-se maior no grupo com pterígio do que no tecido saudável adjacente. Entretanto, a análise dos polimorfismos do receptor da vitamina D nos pacientes com pterígio não revelou qualquer diferença significativa nos polimorfismos BsmI, FokI ou TaqI em comparação com os voluntários saudáveis.(AU)

Association between ABCB1 Polymorphisms and Artesunate-Mefloquine Treatment Responses of Patients with Falciparum Malaria on the Thailand-Myanmar Border.

A decrease in the clinical efficacy of a 3-day artesunate-mefloquine combination treatment was reported in the areas of multidrug-resistant Plasmodium falciparum along the Thailand-Myanmar border. The current study investigated the possible contribution of genetic polymorphisms of the three major genes encoding drug efflux transporters, ABCB1, ABCG2, and ABCC1, to responses to the aforementioned treatment in 91 patients with acute uncomplicated falciparum malaria residing along the Thailand-Myanmar border. Patients carrying homozygous mutant genotype ABCB1 c.1236C>T (TT) were found to have a three-times higher chance of successful treatment with this combination compared with other genotypes (CC and CT). Furthermore, whole blood mefloquine concentrations in these patients with the TT genotype were significantly lower than those of patients carrying the CC genotype. Patients with heterozygous mutant genotype (CT), however, were three-times more likely to experience treatment failure. No significant association was found with the ABCG2 and ABCC1 gene polymorphisms. The results suggest that ABCB1 c.1236C>T polymorphisms could be useful genetic markers for predicting responses to the 3-day artesunate-mefloquine treatment; however, studies using larger sample sizes in different malaria-endemic areas are necessary to confirm this finding. This study highlights the impact of pharmacogenetic factors on antimalarial treatment responses and the basis for the application of control policies in various malaria-endemic areas.

A single G10T polymorphism in HIV-1 subtype C Gag-SP1 regulates sensitivity to maturation inhibitors.

BACKGROUND: Maturation inhibitors (MIs) potently block HIV-1 maturation by inhibiting the cleavage of the capsid protein and spacer peptide 1 (CA-SP1). Bevirimat (BVM), a highly efficacious first-in-class MI against HIV-1 subtype B isolates, elicited sub-optimal efficacy in clinical trials due to polymorphisms in the CA-SP1 region of the Gag protein (SP1:V7A). HIV-1 subtype C inherently contains this polymorphism thus conferring BVM resistance, however it displayed sensitivity to second generation BVM analogs. RESULTS: In this study, we have assessed the efficacy of three novel second-generation MIs (BVM analogs: CV-8611, CV-8612, CV-8613) against HIV-1 subtype B and C isolates. The BVM analogs were potent inhibitors of both HIV-1 subtype B (NL4-3) and subtype C (K3016) viruses. Serial passaging of the subtype C, K3016 virus strain in the presence of BVM analogs led to identification of two mutant viruses-Gag SP1:A1V and CA:I201V. While the SP1:A1V mutant was resistant to the MIs, the CA:I120V mutant displayed partial resistance and a MI-dependent phenotype. Further analysis of the activity of the BVM analogs against two additional HIV-1 subtype C strains, IndieC1 and ZM247 revealed that they had reduced sensitivity as compared to K3016. Sequence analysis of the three viruses identified two polymorphisms at SP1 residues 9 and 10 (K3016: N9, G10; IndieC1/ZM247: S9, T10). The N9S and S9N mutants had no change in MI-sensitivity. On the other hand, replacing glycine at residue 10 with threonine in K3016 reduced its MI sensitivity whereas introducing glycine at SP1 10 in place of threonine in IndieC1 and ZM247 significantly enhanced their MI sensitivity. Thus, the specific glycine residue 10 of SP1 in the HIV-1 subtype C viruses determined sensitivity towards BVM analogs. CONCLUSIONS: We have identified an association of a specific glycine at position 10 of Gag-SP1 with an MI susceptible phenotype of HIV-1 subtype C viruses. Our findings have highlighted that HIV-1 subtype C viruses, which were inherently resistant to BVM, may also be similarly predisposed to exhibit a significant degree of resistance to second-generation BVM analogs. Our work has strongly suggested that genetic differences between HIV-1 subtypes may produce variable MI sensitivity that needs to be considered in the development of novel, potent, broadly-active MIs.

Functional variability of rhesus macaque (Macaca mulatta) NAT2 gene for drug-metabolising arylamine N-acetyltransferase 2.

Human NAT2 is a polymorphic pharmacogene encoding for N-acetyltransferase 2, a hepatic enzyme active towards arylamine and arylhydrazine drugs, including the anti-tubercular antibiotic isoniazid. The isoenzyme also modulates susceptibility to chemical carcinogenesis, particularly of the bladder. Human NAT2 represents an ideal model for anthropological investigations into the demographic adaptation of worldwide populations to their xenobiotic environment. Its sequence appears to be subject to positive selection pressures that are population-specific and may be attributed to gene-environment interactions directly associated with exogenous chemical challenges. However, recent evidence suggests that the same evolutionary pattern may not be observed in other primates. Here, we report NAT2 polymorphism in 25 rhesus macaques (Macaca mulatta) and compare the frequencies and functional characteristics of 12 variants. Seven non-synonymous single nucleotide variations (SNVs) were identified, including one nonsense mutation. The missense SNVs were demonstrated to affect enzymatic function in a substrate-dependent manner, albeit more moderately than certain NAT1 SNVs recently characterised in the same cohort. Haplotypic and functional variability of NAT2 was comparable to that previously observed for NAT1 in the same population sample, suggesting that the two paralogues may have evolved under similar selective pressures in the rhesus macaque. This is different to the population variability distribution pattern reported for humans and chimpanzees. Recorded SNVs were also different from those found in other primates. The study contributes to further understanding of NAT2 functional polymorphism in the rhesus macaque, a non-human primate model used in biomedicine and pharmacology, indicating variability in xenobiotic acetylation that could affect drug metabolism.

Impact of Pharmacogenetic Determinants of Tacrolimus and Mycophenolate on Adverse Events in Renal Transplant Patients.

BACKGROUND: Graft acceptance against immunity is one of the major challenges in solid organ transplant. Immunosuppressive medications have effectively improved the post-transplantation outcome however, it has its own limitations. Genetic polymorphisms in drug-metabolizing enzymes have been identified as the potential targets in developing a pharmacogenetic strategy, to individualize drug dose and also in preventing the adverse events. OBJECTIVE: The rationale of the study was to explore polymorphisms in tacrolimus and mycophenolate metabolic pathways that influence the adverse clinical outcomes in renal transplant recipients. METHODS: A total of 255 renal transplant recipients were analyzed for the pharmacogenetic determinants of tacrolimus (CYP3A5*3 ABCB1 1236 T>C ABCB1 2677 G>A/T ABCB1 3435 T>C) and mycophenolate (UGT1A8*3 UGT1A9 IMPDH I IMPDH II c.787C>T ABCC2 -24 C>T and c.3972C>T) using Sanger sequencing. RESULTS: Acute rejection (AR) was observed in 5.88% of the transplant recipients whereas acute tubular necrosis (ATNs) was observed in 7.45% of the patients within early stage of the maintenance phase. Infections such as urinary tract infection (UTI) and cytomegalovirus (CMV) infection were observed in 11.37% and 12.16% of the patients. The AUC of mycophenolate was significantly higher in patients with increased risk for infections. ABCC2 -24 C>T c.3972C>T polymorphisms and ABCB1 3435 C-allele were associated with reduced risk for infections. ABCC2 rs3740066 was associated with 2.06-fold all-cause mortality risk. CYP3A5 AG- and UGT1A9-440 CC-genotypes showed increased risk and ABCC 3972C>T CC-genotype showed protection against adverse events. CONCLUSION: Genetic variants in tacrolimus and mycophenolate metabolic pathways were found to influence the morbidity and mortality in renal transplant recipients.

Role of Human Arylacetamide Deacetylase (AADAC) on Hydrolysis of Eslicarbazepine Acetate and Effects of AADAC Genetic Polymorphisms on Hydrolase Activity.

Human arylacetamide deacetylase (AADAC) plays a role in the detoxification or activation of drugs and is sometimes involved in the incidence of toxicity by catalyzing hydrolysis reactions. AADAC prefers compounds with relatively small acyl groups, such as acetyl groups. Eslicarbazepine acetate, an antiepileptic drug, is a prodrug rapidly hydrolyzed to eslicarbazepine. We sought to clarify whether AADAC might be responsible for the hydrolysis of eslicarbazepine acetate. Eslicarbazepine acetate was efficiently hydrolyzed by human intestinal and liver microsomes and recombinant human AADAC. The hydrolase activities in human intestinal and liver microsomes were inhibited by epigallocatechin gallate, a specific inhibitor of AADAC, by 82% and 88% of the control, respectively. The hydrolase activities in liver microsomes from 25 human livers were significantly correlated (r = 0.87, P < 0.001) with AADAC protein levels, suggesting that the enzyme AADAC is responsible for the hydrolysis of eslicarbazepine acetate. The effects of genetic polymorphisms of AADAC on eslicarbazepine acetate hydrolysis were examined by using the constructed recombinant AADAC variants with T74A, V172I, R248S, V281I, N366K, or X400Q. AADAC variants with R248S or X400Q showed lower activity than wild type (5% or 21%, respectively), whereas those with V172I showed higher activity than wild type (174%). Similar tendencies were observed in the other four substrates of AADAC; that is, p-nitrophenyl acetate, ketoconazole, phenacetin, and rifampicin. Collectively, we found that eslicarbazepine acetate is specifically and efficiently hydrolyzed by human AADAC, and several AADAC polymorphic alleles would be a factor affecting the enzyme activity and drug response. SIGNIFICANCE STATEMENT: This is the first study to clarify that arylacetamide deacetylase (AADAC) is responsible for the activation of eslicarbazepine acetate, an antiepileptic prodrug, to eslicarbazepine, an active form, in the human liver and intestines. In addition, we found that several AADAC polymorphic alleles would be a factor affecting the enzyme activity and drug response.

PEAR1 polymorphisms as a prognostic factor in hemostasis and cardiovascular diseases.

Platelet Endothelial Aggregation Receptor (PEAR1), as a platelet receptor, plays a vital role in hemostasis. This receptor, by its extracellular part, causes platelet adhesion and consequently initiates platelet aggregation. Dysfunction of PEAR1 can disrupt platelet aggregation in patients with cardiovascular diseases (CVDs). The content used in this paper has been taken from English language articles (2005-2020) retrieved from Pubmed database and Google scholar search engine using "Cardiovascular Disease", "PEAR1", "Polymorphism", and "Platelet Aggregation" keywords. Some PEAR1 polymorphisms can disrupt homeostasis and interfere with the function mechanism of cardiac drugs. Since polymorphisms in this gene affect platelet function and the platelet aggregation process, PEAR1 could be further studied in the future as an essential factor in controlling the treatment process of patients with cardiovascular diseases. PEAR1 polymorphisms through disruption of the platelet aggregation process can be a risk factor in patients with CVDs. Therefore, controlling patients through genetic testing and the evaluation of PEAR1 polymorphisms can help improve the treatment process of patients. According to the studies on the PEAR1 gene and the effect of different polymorphisms on some crucial issues in CVDs patients (changes in platelet activity), it is clear that if there is a significant relationship between polymorphisms and CVDs, they can be used as prognostic and diagnostic markers. This study aims to evaluate the prognosis and drug treatment of the PEAR1 gene in CVDs patients.

[Analysis of drug - resistant gene polymorphisms in Plasmodium falciparum imported from Equatorial Guinea to Shandong Province in 2015 and 2016].

OBJECTIVE: To investigate the drug-resistant gene polymorphisms in Plasmodium falciparum imported from Equatorial Guinea to Shandong Province. METHODS: From 2015 to 2016, blood samples were collected from imported P. falciparum malaria patients returning from Equatorial Guinea to Shandong Province, and genome DNA of the malaria parasite was extracted. The drug-resistant Pfcrt, Pfmdr1, Pfdhfr, Pfdhps, and K13 genes of P. falciparum were amplified using a PCR assay, followed by DNA sequencing, and the sequences were aligned. RESULTS: The target fragments of all 5 drug-resistant genes of P. falciparum were successfully amplified and sequenced. There were 72.8%, 18.6%, and 8.6% of P. falciparum parasites carrying the wild-, mutant-, and mixed-type Pfcrt gene, respectively, and all mutant haplotypes were CVIET (the underline indicates the mutation site). There were 20.0%, 61.4% and 18.6% of P. falciparum parasites carrying the wild-, mutant-, and mixed-type Pfmdr1 gene, respectively, and the mutant haplotypes mainly included YF and NF (the underlines indicate the mutation sites). There were 1.4%, 98.6%, and 0 of P. falciparum parasites carrying the wild-, mutant-, and mixed-type Pfdhfr gene, respectively, and AIRNI was the predominant mutant haplotype (the underline indicates the mutation site). There were 1.4%, 94.3%, and 4.3% of P. falciparum parasites carrying the wild-, mutant-, and mixed-type Pfdhps gene, respectively, and SGKAA was the predominant mutant haplotype (the underline indicates the mutation site). The complete drug-resistant IRNGE genotype consisted of 8.6% of the Pfdhfr and Pfdhps genes, and the K13 gene A578S mutation occurred in 1.4% of the parasite samples. CONCLUSIONS: There are mutations in the Pfcrt, Pfmdr1, Pfdhfr, Pfdhps, and K13 genes of P. falciparum imported from Equatorial Guinea to Shandong Province, with a low frequency in the Pfcrt gene mutation and a high frequency in the Pfmdr1, Pfdhfr, and Pfdhps gene mutations, and the K13 gene A578S mutation is detected in the parasite samples.

Anti-IL-6 receptor antibody treatment for severe COVID-19 and the potential implication of IL-6 gene polymorphisms in novel coronavirus pneumonia / Tratamiento con anticuerpos anti-receptor de IL-6 para COVID-19 grave y la posible implicación de polimorfismos del gen IL-6 en la nueva neumonía por coronavirus

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Prevalence and types of genetic polymorphisms of CYP2C19 and their effects on platelet aggregation inhibition by clopidogrel.

OBJECTIVE: The current study was conducted to determine the distribution of genetic polymorphisms in CYP2C19 in Iraqi patients and their role in inter-individual variability of clopidogrel efficacy. PATIENTS AND METHODS: A prospective controlled study was done on 100 patients under high risk of cardiovascular diseases who started clopidogrel prophylactic therapy. Polymerase chain reaction-restriction fragment length polymorphism method was used to determine the existence of the CYP2C19 gene mutation. Vasodilator-stimulated phosphoprotein (VASP) index baseline besides one-month post-therapy was analyzed by dual-color flow cytometry analysis. RESULTS: Eight gene mutations of CYP2C19 were found (*1/*1), (*1/*2), (*1/*3), (*1/*8), (*1/*17), (*2/*2), (*2/*4), and (*3/*3) with higher prevalent CYP2C19*1 gene. Homozygous CYP2C19*1 allele was shown to be the rapid metabolizer comparing to the heterozygous CYP2C19*1 allele, whereas, CYP2C19*2 and CYP2C19*3 were resistant alleles and were present in 28% of patients. The analysis of VASP phosphorylation produces accurate inter-individual response variability in platelets inhibition by antiplatelet drugs. CONCLUSIONS: In vitro gene analysis and VASP index improve the clinical outcome of a patient candidate to clopidogrel as prophylaxis in cardiovascular events.

Influenza immunization does not predominantly alter levels of phenytoin, and cytochrome P-450 enzymes in epileptic patients receiving phenytoin monotherapy.

OBJECTIVE: The study aims to test the effect of influenza vaccination on phenytoin, CYP2C9, and IFNγ levels in epileptic patients receiving phenytoin monotherapy METHODS: Thirty-one epileptic patients receiving stable-dose phenytoin monotherapy were enrolled onto the study. Serum concentrations of phenytoin, CYP2C9, and IFNγ were compared before and after influenza immunization. The participants were given 0.5 mL of quadrivalent influenza vaccine types A and B subvirion. Blood samples were drawn at baseline, and days 3, 7, 14 post-immunization. The outcomes were levels of phenytoin, CYP2C9, IFNγ, and the incidence of adverse events. RESULTS: No significant changes in serum phenytoin, IFNγ, and CYP2C9 levels between baseline and days 3, 7, and 14 after immunization were found. The mean levels of phenytoin, IFNγ, and CYP2C9, respectively, were 11.94 ± 7.43, 1.14 ± 0.98, and 47.69 ± 37.53 pg/mL (baseline); 12.15 ± 6.57, 2.13 ± 3.41, and 49.44 ± 39.83 pg/mL (day 3); 12.19 ± 7.69, 1.15 ± 0.94, and 49.48 ± 33.83 pg/mL (day 7); 12.79 ± 7.94, 2.15 ± 3.11, and 53.65 ± 40.91 pg/mL (day 14). The incidence of vaccine-related adverse events, which were generally mild and resolved without clinical consequences, was 58.1 %. No seizure or changes in seizure frequency were observed during the study. One patient experienced dizziness and ataxia which were symptoms attributed to phenytoin toxicity (34.57 µg/mL) by day 14. CONCLUSIONS: Influenza vaccine has no significant effect on the serum phenytoin and CYP2C9 levels in epileptic patients receiving chronic phenytoin monotherapy. The administration of influenza vaccine to epileptic patients receiving phenytoin monotherapy appears to be safe. Therefore, it is not necessary to routinely measure the serum phenytoin level after influenza immunization.

Associations between Malaria-Preventive Regimens and Plasmodium falciparum Drug Resistance-Mediating Polymorphisms in Ugandan Pregnant Women.

Intermittent preventive treatment in pregnancy (IPTp) with monthly sulfadoxine-pyrimethamine (SP) is recommended for malaria-endemic parts of Africa, but efficacy is compromised by resistance, and, in recent trials, dihydroartemisinin-piperaquine (DP) has shown better antimalarial protective efficacy. We utilized blood samples from a recent trial to evaluate selection by IPTp with DP or SP of Plasmodium falciparum genetic polymorphisms that alter susceptibility to these drugs. The prevalence of known genetic polymorphisms associated with altered drug susceptibility was determined in parasitemic samples, including 375 collected before IPTp drugs were administered, 125 randomly selected from those receiving SP, and 80 from those receiving DP. For women receiving DP, the prevalence of mixed/mutant sequences was greater in samples collected during IPTp than that in samples collected prior to the intervention for PfMDR1 N86Y (20.3% versus 3.9%; P < 0.001), PfMDR1 Y184F (73.0% versus 53.0%; P < 0.001), and PfCRT K76T (46.4% versus 24.0%; P < 0.001). Considering SP, prior to IPTp, the prevalence of all 5 common antifolate mutations was over 92%, and this prevalence increased following exposure to SP, although none of these changes were statistically significant. For two additional mutations associated with high-level SP resistance, the prevalence of PfDHFR 164L (13.7% versus 4.0%; P = 0.004), but not PfDHPS 581G (1.9% versus 3.0%; P = 0.74), was greater in samples collected during IPTp compared to those collected before the intervention. Use of IPTp in Uganda selected for parasites with mutations associated with decreased susceptibility to IPTp regimens. Thus, a potential drawback of IPTp is selection of parasites with decreased drug susceptibility.

Investigating selected host and parasite factors potentially impacting upon seasonal malaria chemoprevention in Bama, Burkina Faso.

BACKGROUND: Since 2014, seasonal malaria chemoprevention (SMC) with amodiaquine-sulfadoxine-pyrimethamine (AQ-SP) has been implemented on a large scale during the high malaria transmission season in Burkina Faso. This paper reports the prevalence of microscopic and submicroscopic malaria infection at the outset and after the first round of SMC in children under 5 years old in Bama, Burkina Faso, as well as host and parasite factors involved in mediating the efficacy and tolerability of SMC. METHODS: Two sequential cross-sectional surveys were conducted in late July and August 2017 during the first month of SMC in a rural area in southwest Burkina Faso. Blood smears and dried blood spots were collected from 106 to 93 children under five, respectively, at the start of SMC and again 3 weeks later. Malaria infection was detected by microscopy and by PCR from dried blood spots. For all children, day 7 plasma concentrations of desethylamodiaquine (DEAQ) were measured and CYP2C8 genetic variants influencing AQ metabolism were genotyped. Samples were additionally genotyped for pfcrt K76T and pfmdr1 N86Y, molecular markers associated with reduced amodiaquine susceptibility. RESULTS: 2.8% (3/106) of children were positive for Plasmodium falciparum infection by microscopy and 13.2% (14/106) by nested PCR within 2 days of SMC administration. Three weeks after SMC administration, in the same households, 4.3% (4/93) of samples were positive by microscopy and 14.0% (13/93) by PCR (p = 0.0007). CYP2C8*2, associated with impaired amodiaquine metabolism, was common with an allelic frequency of 17.1% (95% CI 10.0-24.2). Day 7 concentration of DEAQ ranged from 0.48 to 362.80 ng/mL with a median concentration of 56.34 ng/mL. Pfmdr1 N86 predominated at both time points, whilst a non-significant trend towards a higher prevalence of pfcrt 76T was seen at week 3. CONCLUSION: This study showed a moderate prevalence of low-level malaria parasitaemia in children 3 weeks following SMC during the first month of administration. Day 7 concentrations of the active DEAQ metabolite varied widely, likely reflecting variability in adherence and possibly metabolism. These findings highlight factors that may contribute to the effectiveness of SMC in children in a high transmission setting.