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Antimicrobial-product package inserts and insufficient staffing impede routine carbapenem monitoring in the inpatient setting in Japan. The collaboration between antimicrobial stewardship teams and clinical pharmacists was associated with a sustained improvement in carbapenem dosing optimization. Our findings could be of use to countries with inadequate monitoring of carbapenem antimicrobial use.
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Spinal muscular atrophy (SMA) is an autosomal recessive neuromuscular disorder. Al-though there was no cure for SMA, newly developed therapeutic drugs (nusinersen, onasemnogene abeparvovec, and risdiplam) have been proven effective for the improvement of motor function and prevention of respiratory insufficiency of infants with SMA. Nusinersen was introduced in Japan in 2017 and onasemnogene abeparvovec in 2020. We hypothesized that the introduction of these drugs might influence the incidence of SMA (more precisely, increase the diagnosis rate of SMA) in Japan. To test this hypothesis, we conducted a second epidemiological study of infantile SMA using questionnaires in Shikoku, Japan between October 2021 and February 2022. The incidence of infantile SMA during the period 2016-2020 was 7.08 (95% confidence interval [CI] 2.45-11.71) per 100,000 live births. According to our previous epidemiological study, the incidence of infantile SMA during 2011-2015 was 2.70 (95% CI 0.05-5.35) per 100,000 live births. The increased incidence of infantile SMA suggests that the widespread news in Japan regarding the introduction of therapeutic agents, nusinersen and onasemnogene abeparvovec, raised clinicians' awareness about SMA, leading to increased and earlier diagnosis of SMA in Shikoku.
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Introduction: Fetal growth restriction (FGR) is a clinical condition wherein a fetus fails to achieve the expected growth potential. Although FGR is the leading cause of perinatal morbidity and mortality, there is a lack of knowledge about the long-term developmental outcomes of children who had FGR in Japan. Here, we sought to clarify the features of neurodevelopmental outcomes in preterm-born children with severe FGR (sFGR) and identify associated clinical factors. Methods: The clinical data of 26 preterm sFGR cases and 26 preterm appropriate for gestational age (AGA) cases with a similar gestational age distribution were reviewed retrospectively. Developmental quotient (DQ) scores assessed during the 1- and 2-year corrected ages using the Kyoto Scale of Psychological Development were analyzed. Results: sFGR was diagnosed at 26 (18-34) weeks of gestation, and the gestational age at delivery was 31 (25-36) weeks. The overall DQ scores of children in the sFGR group were significantly lower than those in the AGA group (80 vs. 90.5, P = 0.0127). Of the three areas that comprise the DQ (Postural-Motor, Cognitive-Adaptive, and Language-Social), the sFGR group only showed significantly lower DQ scores (72.5 vs. 88, P = 0.0255) in the Language-Social area. Both fetal body weight and fetal body weight Z score at birth significantly correlated with the DQ scores (r = 0.4912, P = 0.0108, and r = 0.5621, P = 0.0028), whereas neither the duration of fetal growth arrest nor the gestational age at birth correlated with the DQ scores (r = 0.3598, P = 0.0842, and r = 0.3522, P = 0.0776). Conclusions: Our results indicate that preterm-born children with sFGR have greater neurodevelopmental impairment than preterm-born children without FGR, specifically in terms of the DQ scores for the Language-Social area. It is imperative to encourage continuous long-term follow-up and appropriate interventions after birth.
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We report a haemodialysis patient with end-stage renal failure whom a pharmacist aided in the management of acyclovir (ACV) encephalopathy, which may have been related to valacyclovir hydrochloride (VACV) administered without sufficient dose reduction. The patient 78 years was admitted with a tentative diagnosis of varicella zoster viral meningitis. A pharmacist suspected ACV encephalopathy related to excessive VACV administration and raised a query with the attending physician. According to the pharmacist's proposal, ACV administration was discontinued and continuous hemodiafiltration (CHDF) was performed. On day 5 of hospitalisation, the consciousness disorder was improved. In this report, we showed the detailed CHDF conditions of the present case, and the contribution of a pharmacist to treating and avoiding ACV encephalopathy was discussed.
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Encefalopatias , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Aciclovir/efeitos adversos , Encefalopatias/induzido quimicamente , Encefalopatias/tratamento farmacológico , Humanos , Farmacêuticos , ValaciclovirRESUMO
Tazobactam / piperacillin (TAZ / PIPC) is an injectable combination drug consisting of a broad-spectrum penicillin and a ß-lactamase inhibitor. This antimicrobial has a wide spectrum of efficacy against both Gram-positive bacteria and anaerobes. Adverse events usually present as diarrhea or liver dysfunctionâ ;â agranulocytosis has not been reported in Japanese patients with puerperal disorders. However, we report a 32-year-old Japanese woman who received TAZ / PIPC to treat an intraperitoneal infection that developed after complications related to transvaginal delivery. Within 14 days of beginning TAZ / PIPC therapy, the patient developed agranulocytosis, indicated by a white blood cell count of 1900 cells / µL and a neutrophil count of 475 cells / µL. We discontinued TAZ / PIPC at this point and changed the antimicrobial to meropenem. Seven days later, her white blood cell count increased to 3700 cells / µL (neutrophil countâ :â 1684 cells / µL), and the intraperitoneal infection resolved. Patients receiving TAZ / PIPC should be monitored periodically for agranulocytosis as well as for diarrhea and liver dysfunction. J. Med. Invest. 68 : 368-371, August, 2021.
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Agranulocitose , Piperacilina , Adulto , Agranulocitose/induzido quimicamente , Agranulocitose/tratamento farmacológico , Antibacterianos/efeitos adversos , Quimioterapia Combinada , Feminino , Humanos , Ácido Penicilânico/efeitos adversos , Piperacilina/efeitos adversos , Combinação Piperacilina e TazobactamRESUMO
Epidermal growth factor receptor (EGFR)-tyrosine kinase inhibitors such as afatinib are used for non-small cell lung cancer (NSCLC) and show varying efficacy depending on EGFR gene mutation. Few studies have examined the relationship between EGFR gene mutations and the adverse events of afatinib in NSCLC. This retrospective study included 32 Japanese patients with NSCLC with EGFR gene mutation who were treated with afatinib between May 2014 and August 2018 at Kagawa University Hospital. Among the 32 Japanese patients with NSCLC treated with afatinib, 19 patients were positive for exon 19 deletion mutation (Del 19) and 13 patients were negative for Del 19. The incidence of grade ≥â 2 skin rash was slightly higher in patients positive for Del 19 (42.1% vs. 7.7%, Pâ =â 0.050). No significant differences were detected in other adverse events between the two patient groups. Patients positive for Del 19 also showed significantly longer median progression-free survival (288 vs. 84 days, Pâ =â 0.049). Our study indicates a higher incidence of skin rash associated with afatinib treatment in Japanese patients with NSCLC positive for Del 19 compared with patients without Del 19. The Del 19 positive patient group also showed better progression-free survival. J. Med. Invest. 68 : 125-128, February, 2021.
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Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Afatinib/efeitos adversos , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/genética , Receptores ErbB/genética , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/genética , Mutação , Estudos RetrospectivosRESUMO
BACKGROUND: Spinal muscular atrophy (SMA) is an inherited neuromuscular disorder associated with spinal motor neuron loss and characterized by generalized muscle weakness. Only a few reports exist on SMA epidemiology in Japan. Additionally, nusinersen recently became available as a treatment for this condition. We estimated the prevalence of each type of SMA on Shikoku, Japan's fourth-largest major island. METHODS: We sent a questionnaire to all 131 hospitals in Shikoku that have pediatrics or neurology departments from March to September 2019, asking whether each hospital had SMA patients at that time. If so, we sent a second questionnaire to obtain more detailed information on the clinical data and treatment of each patient. RESULTS: A total of 117 hospitals (89.3%) responded to our first questionnaire, and 21 SMA patients were reported, 16 of whom had homozygous deletion of SMN1. Of the 21, nine had SMA type 1, five were type 2, five were type 3, one was type 4, and one was unidentified. The estimated prevalence for all instances of SMA and 5q-SMA was 0.56 and 0.43 per 100,000 people, respectively. Thirteen patients had received nusinersen therapy. Its outcomes varied from no obvious effects and being unable to sit to being able to sit independently. CONCLUSION: Our data showed the prevalence of SMA types 2 and 3 was relatively low on Shikoku compared with previous reports from other countries, suggesting delayed diagnosis may affect the results. Remaining motor function may be one predicting factor. Greater awareness of SMA among clinicians and patients seems necessary for more accurate epidemiological studies.
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Atrofia Muscular Espinal/epidemiologia , Adolescente , Adulto , Idoso , Criança , Pré-Escolar , Feminino , Homozigoto , Humanos , Lactente , Recém-Nascido , Japão/epidemiologia , Masculino , Pessoa de Meia-Idade , Atrofia Muscular Espinal/genética , Mutação/genética , Oligonucleotídeos/uso terapêutico , Prevalência , Deleção de Sequência/genética , Inquéritos e Questionários , Proteína 1 de Sobrevivência do Neurônio Motor/genética , Proteína 2 de Sobrevivência do Neurônio Motor/genética , Adulto JovemRESUMO
INTRODUCTION: With improved treatments, patients with Duchenne muscular dystrophy (DMD) can survive far beyond adolescence. However, advanced-stage DMD patients are at risk of developing renal dysfunction. In this study, long-term renal function outcomes and associated risk factors in advanced stage DMD were analyzed. METHODS: Fifty-one patients were classified into three different age groups (<20, 20-29, and ≥30 years of age), and cystatin C (CysC) levels were compared among groups. RESULTS: Median serum CysC levels were 0.74 mg/L, 0.63 mg/L, and 0.76 mg/L in the age groups of <20, 20-29, and ≥30 years, respectively (P = .003). Five of the nine patients in the ≥30 years age group showed elevated serum CysC and decreased cardiac function compared with the other four in the group (P = .014). DISCUSSION: Our results indicate an association between cardiac and renal dysfunction in patients with advanced-stage DMD.
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Nefropatias/etiologia , Distrofia Muscular de Duchenne/complicações , Adolescente , Adulto , Envelhecimento , Criança , Pré-Escolar , Cistatina C/sangue , Progressão da Doença , Feminino , Cardiopatias/etiologia , Cardiopatias/fisiopatologia , Testes de Função Cardíaca , Humanos , Nefropatias/fisiopatologia , Testes de Função Renal , Masculino , Distrofia Muscular de Duchenne/fisiopatologia , Fatores de Risco , Adulto JovemRESUMO
BACKGROUND: Spinal muscular atrophy (SMA) is an autosomal recessive disorder caused by homozygous mutations in the SMN1 gene. SMA has long been known to be the most common genetic cause of infant mortality. However, there have been no reports on the epidemiology of infantile SMA (types 1 and 2) based on genetic testing in Japan. In this study, we estimated the incidence of infantile SMA on Shikoku Island, which is a main island of Japan and consists of four prefectures: Ehime, Kagawa, Tokushima and Kochi. METHODS: A questionnaire was sent to 91 hospitals on Shikoku Island to investigate the number of SMA infants born from 2011 to 2015. A second questionnaire was then sent to confirm the diagnoses of SMA based on clinical and genetic features. RESULTS: Responses were received from all of the hospitals, and four patients were diagnosed with infantile SMA among 147,950 live births. We estimated the incidence of infantile SMA patients as 2.7 per 100,000 live births (95% confidence interval, 0.1-5.4). A comparison of the four prefectures indicated that the incidence of infantile SMA was significantly higher in Ehime Prefecture than in the other three prefectures; 5.6 per 100,000 live births (95% confidence interval, -0.7 to 11.9) in Ehime Prefecture and 1.1 per 100,000 live births (95% confidence interval, -1.0 to 3.1) in the other prefectures. CONCLUSION: We estimated the incidence of infantile SMA in an isolated area of Japan. For more precise determination of the incidence of infantile SMA, further studies that include neonatal screening will be needed.
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Atrofias Musculares Espinais da Infância/epidemiologia , Feminino , Humanos , Incidência , Lactente , Japão/epidemiologia , Masculino , Atrofias Musculares Espinais da Infância/genética , Proteína 1 de Sobrevivência do Neurônio Motor/genética , Proteína 2 de Sobrevivência do Neurônio Motor/genéticaRESUMO
We evaluated the efficacy of linezolid treatment in 6 children with health care-associated meningitis or ventriculitis (HCAMV) caused by gram-positive cocci. All children were diagnosed and treated at the Ehime University Hospital between January 2010 and December 2017. Of these, 5 were treated with linezolid as an empirical therapy. In these 5 patients, vancomycin was initially used but was changed to linezolid because of cerebrospinal fluid (CSF) culture positivity (n = 3) and a high minimum inhibitory concentration of vancomycin (n = 2). The most common HCAMV pathogens were methicillin-resistant coagulase-negative staphylococci (n = 3). In 3 patients, vancomycin concentration was low in CSF but reached the target concentration in serum, while linezolid concentration was high in both CSF and serum. HCAMV treatment using antimicrobial agents with poor CSF penetration may increase the likelihood of therapy failure. Linezolid is more susceptible as the first-line treatment for HCAMV compared with vancomycin.
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Antibacterianos/uso terapêutico , Ventriculite Cerebral/tratamento farmacológico , Infecção Hospitalar/tratamento farmacológico , Linezolida/uso terapêutico , Meningite/tratamento farmacológico , Adolescente , Ventriculite Cerebral/etiologia , Estudos de Coortes , Infecção Hospitalar/microbiologia , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Meningite/etiologia , Resultado do TratamentoRESUMO
Bevacizumab (BV), an inhibitor of vascular endothelial growth factor, is used in combination with paclitaxel (PTX) to treat advanced breast cancer. Hypertension and proteinuria are characteristic adverse events of BV therapy. We assessed the potential of these adverse events as predictors of BV treatment responses. Our results revealed that groups that developed hypertension and proteinuria early (by day 56) had a stronger antitumor response (Fisher's exact test p<0.05). However, no significant difference was observed in progression-free survival (the Kaplan-Meier method and Log-rank test). As a reference, age, the treatment line, subtypes, liver and renal function, diabetes mellitus and hyperlipidemia history, body mass index, influencing concomitant medicine, average relative dose intensity and hematotoxicity did not significantly differ between groups with or without hypertension and with or without proteinuria. These results indicate the potential of the development of hypertension and proteinuria as predictors of improved outcomes with PTX plus BV therapy in patients with breast cancer. However, since both adverse events may preclude the continuation of treatment, their earlier management may be required.
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Inibidores da Angiogênese/uso terapêutico , Antineoplásicos Imunológicos/uso terapêutico , Bevacizumab/uso terapêutico , Neoplasias da Mama/tratamento farmacológico , Hipertensão/induzido quimicamente , Proteinúria/induzido quimicamente , Adulto , Idoso , Inibidores da Angiogênese/efeitos adversos , Antineoplásicos Imunológicos/efeitos adversos , Bevacizumab/efeitos adversos , Feminino , Humanos , Pessoa de Meia-Idade , Terapia Neoadjuvante , Paclitaxel/uso terapêutico , Resultado do TratamentoRESUMO
AIM: We conducted a self-administered survey on the perception of teachers toward human papillomavirus (HPV) vaccine to determine the ways to increase their willingness to encourage its use. METHODS: Answers were obtained both prior to and after having the teachers read five brief information articles: (i) cervical cancer knowledge, (ii) vaccine knowledge, (iii) result of a survey in Nagoya, (iv) news report of the World Health Organization statement and (v) articles written by Dr Muranaka, a journalist. RESULTS: Most of the respondents (180/247) did not know about the natural history of cervical cancer. Only 36% knew that HPV is the cause of cervical cancer, although 63% knew that HPV vaccine would prevent cervical cancer. Few respondents had knowledge regarding adverse events following immunization and the survey results from Nagoya. Among those who were initially negative for the HPV vaccine, only 43% revealed that they fully understood its safety and only 29% reversed their opinion to recommend vaccination to their daughters and/or students, even after reading our informational material. The most useful information for changing their attitudes was to increase their understanding of vaccines and informing them about Nagoya city survey results. They mostly wanted a proof of the preventive effects of the vaccine on cervical cancer in Japan. CONCLUSION: Gynecologists and pediatricians must proactively communicate accurate scientific information to the government and the media to spread awareness among people in Japan. Also, we must try to demonstrate the capabilities of this vaccine to prevent cervical cancer and/or its precancerous lesions.
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Conhecimentos, Atitudes e Prática em Saúde , Infecções por Papillomavirus/prevenção & controle , Vacinas contra Papillomavirus , Professores Escolares/estatística & dados numéricos , Neoplasias do Colo do Útero/prevenção & controle , Adulto , Feminino , Humanos , Japão , Masculino , Pessoa de Meia-IdadeRESUMO
A 3-month-old girl exhibited asymmetric abnormal eye movement and unilateral dystonic posture intermittently after the first few days of life. Unilateral ocular deviation or nystagmus were the main signs of abnormal eye movements. She was suspected to have alternating hemiplegia of childhood (AHC) despite the absence of apparent alternating hemiplegic episodes. Gene analysis revealed a de-novo missense mutation (Asp801Asn) of ATP1A3. AHC is a rare neurodevelopmental disorder characterized by recurrent transient attacks of hemiplegia affecting the unilateral or bilateral side of the body; in most cases, these attacks begin in the first 6 months of life. Initial symptoms of AHC are not alternating hemiplegic episodes, but rather asymmetric abnormal eye movement, dystonic posture, or seizures. It is difficult to diagnose AHC early because no specific findings are observed in the diagnostic laboratory or neuroradiological examinations. Early diagnosis is important because flunarizine may have a protective effect on the severe motor deterioration associated with AHC. Asymmetric abnormal eye movement could be an important clinical symptom for the diagnosis of AHC in early infancy.
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Hemiplegia/diagnóstico , Transtornos da Motilidade Ocular/fisiopatologia , Feminino , Humanos , Lactente , Imageamento por Ressonância Magnética , PosturaRESUMO
A 6-year-old boy with normal development experienced tonic-clonic seizures and myoclonus. His electroencephalogram showed epileptic discharge and he was administered antiepileptic drugs ; however, they were ineffective. Antiepileptic drugs were discontinued temporarily because of no ictal recordings. He could not walk unaided and his speech reduced gradually. He was admitted to our hospital at the age of seven years and eight months. He experienced daily tonic-clonic seizures and myoclonus. Epileptic encephalopathy related to autoimmunity was suspected as he had psychomotor regression and his cerebrospinal and serum anti-glutamate receptor antibody (anti-GluR) levels were elevated. After being administered immunoglobulins, his motor and cognitive functions improved and his seizures almost stopped. After one year, he could walk unaided and speak fluently. We strongly suspect an autoimmune reaction to be the pathological cause because of the effectiveness of immunoglobulin treatment. Immunoglobulin interventions should be considered in patients with unknown-cause, sub-acute onset, and destructively progressive epileptic encephalopathy.
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Epilepsia/tratamento farmacológico , Imunização Passiva , Imunoglobulinas/uso terapêutico , Criança , Eletroencefalografia , Epilepsia/complicações , Epilepsia/diagnóstico por imagem , Epilepsia/fisiopatologia , Humanos , Masculino , Tomografia por Emissão de Pósitrons , Resultado do TratamentoRESUMO
Duchenne muscular dystrophy (DMD) is a progressive muscular disorder in which respiratory and heart failures are the main causes of death. Intensive intervention in respiratory and cardiac function has dramatically improved the prognosis; however, dysfunction in other multiple organs may emerge in the later stages of the disease. We report the case of four non-ambulatory DMD patients who presented with renal failure. Common findings included decreased fluid intake, use of diuretics, and presence of chronic heart failure. The levels of serum cystatin C (CysC), a marker of kidney function unaffected by reduced muscle mass, were elevated in all four patients. In two patients, renal failure improved by increasing fluid intake, and discontinuing or reducing the dose of diuretics. The findings suggest that non-ambulatory DMD patients are at a risk of reduced kidney perfusion, which potentially leads to prerenal failure. Therefore, in DMD patients, dehydration signs and CysC levels should be monitored.
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Distrofia Muscular de Duchenne/complicações , Insuficiência Renal/complicações , Insuficiência Renal/diagnóstico , Adolescente , Adulto , Nitrogênio da Ureia Sanguínea , Cistatina C/sangue , Ingestão de Líquidos , Distrofina/genética , Humanos , Masculino , Distrofia Muscular de Duchenne/sangue , Mutação , Insuficiência Renal/sangue , Insuficiência Renal/prevenção & controle , Fatores de RiscoRESUMO
OBJECTIVE: Neurological manifestations including psychomotor developmental delay and epilepsy in patients with Angelman syndrome caused by ubiquitin protein ligase E3A (UBE3A) mutations has been considered similar but is relatively milder than that in patients with deletion-type Angelman syndrome. This makes the diagnosis of the former subgroup often difficult. We here characterized epilepsy, specifically the types of tremulous movement, in 4 patients (age, 3-38years) with Angelman syndrome caused by UBE3A mutations. METHODS: Ictal electroencephalography was used to record episodic tremors in all study patients. Jerk-locked averaging was performed using digital electroencephalography and surface electromyogram data from patients who were monitored for 24h. RESULTS: All patients had tremors in the limbs, head, and trunk, which resulted in 2 patients falling backward. These tremors lasted several seconds, and could emerge in clusters for hours in older patients. In addition, the tremors coincided with 7-8Hz rhythmic activity with a frontocentral predominance, diffuse spike-wave bursts, or no apparent change on electroencephalography. In 2 patients, these tremors were confirmed as cortical myoclonus using jerk-locked averaging. The other seizure types were isolated generalized myoclonus and tonic seizures. None of the patients experienced atypical absence seizures. Levetiracetam therapy was effective in controlling the myoclonic events in 2 of the 3 patients. CONCLUSION: Semirhythmic myoclonus is common in patients with Angelman syndrome caused by UBE3A mutations, and such myoclonic events are often life disabling. The preserved expression of gamma-aminobutyric acid type A receptor subunit genes located proximal to UBE3A might explain the low prevalence of absence seizures in this population.
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Síndrome de Angelman/complicações , Síndrome de Angelman/genética , Mutação/genética , Mioclonia/etiologia , Tremor/etiologia , Ubiquitina-Proteína Ligases/genética , Adolescente , Adulto , Ondas Encefálicas/genética , Pré-Escolar , Análise Mutacional de DNA , Eletroencefalografia , Eletromiografia , Feminino , Humanos , MasculinoRESUMO
Bayesian estimation enables the individual pharmacokinetic parameters of the medication administrated to be estimated using only a few blood concentrations. Due to wide inter-individual variability in the pharmacokinetics of methotrexate (MTX), the concentration of MTX needs to be frequently determined during high-dose MTX therapy in order to prevent toxic adverse events. To apply the benefits of Bayesian estimation to cases treated with this therapy, we attempted to develop an estimation method using the Bayesian least-squares method, which is commonly used for therapeutic monitoring in a clinical setting. Because this method hypothesizes independency among population pharmacokinetic parameters, we focused on correlations among population pharmacokinetic parameters used to estimate individual parameters. A two-compartment model adequately described the observed concentration of MTX. The individual pharmacokinetic parameters of MTX were estimated in 57 cases using the maximum likelihood method. Among the available parameters accounting for a 2-compartment model, V1, k10, k12, and k21 were found to be the combination showing the weakest correlations, which indicated that this combination was best suited to the Bayesian least-squares method. Using this combination of population pharmacokinetic parameters, Bayesian estimation provided an accurate estimation of individual parameters. In addition, we demonstrated that the degree of correlation among population pharmacokinetic parameters used in the estimation affected the precision of the estimates. This result highlights the necessity of assessing correlations among the population pharmacokinetic parameters used in the Bayesian least-squares method.
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Teorema de Bayes , Metotrexato/administração & dosagem , Metotrexato/farmacocinética , Modelos Estatísticos , Modelagem Computacional Específica para o Paciente , Adolescente , Adulto , Idoso , Neoplasias Ósseas/tratamento farmacológico , Criança , Relação Dose-Resposta a Droga , Humanos , Análise dos Mínimos Quadrados , Linfoma/tratamento farmacológico , Pessoa de Meia-Idade , Osteossarcoma/tratamento farmacológico , Estudos Retrospectivos , Adulto JovemRESUMO
Hepatocyte growth factor (HGF) stimulates migration and proliferation of keratinocytes and has been suggested to be involved in wound healing. The cationic antibiotic polymyxin B (PMB) is commonly used as a topical antibiotic for wound care. If PMB possesses an HGF-inducing activity, the antibiotic is potentially beneficial for wound healing in addition to minimizing chances of infection. In this study, we found that PMB markedly induced HGF production from various types of cells including human dermal fibroblasts. Its effect was stronger than the effects of epidermal growth factor and cholera toxin and was comparable to the effect of 8-bromo-cAMP. Among the polymyxin family and polymyxin derivatives, colistin was also effective, whereas colistin methanesulfonate had only a marginal effect and PMB nonapeptide was ineffective. The stimulatory effect of PMB was accompanied by upregulation of HGF gene expression. Increase in phosphorylation of extracellular signal-regulated protein kinase (ERK) and c-Jun N-terminal kinase (JNK) was observed from 0.25 h to 6h after the addition of PMB, while increase in phosphorylation of p38 mitogen-activated protein kinase (MAPK) was detected from 24h to 60 h after PMB addition. The MAPK/ERK kinase inhibitor PD98059, the JNK inhibitor SP600125 and the p38 MAPK inhibitor SB203580 all potently inhibited PMB-induced HGF production. Lastly, proliferation of human dermal fibroblasts was significantly stimulated by PMB. These results indicate that PMB-induced HGF production and proliferation of human dermal fibroblasts and suggest that activation of MAPKs is involved in the induction of HGF production.