In vivo activation of PEGylated long circulating lipid nanoparticle to achieve efficient siRNA delivery and target gene knock down in solid tumors.

We developed a lipid nanoparticle formulation (LNPK15) to deliver siRNA to a tumor for target gene knock down. LNPK15 is highly PEGylated with 3.3% 1,2-distearoyl-sn-glycero-3-phosphatidylethanolamine-N-(polyethylene glycol-2000) (PEG-DSPE) and shows a long duration: the half-lives of siRNA in LNPK15 were 15.2 and 27.0h in mice and monkeys, respectively. Although LNPK15 encapsulating KRAS-targeting siRNA (LNPK15/KRAS) had very weak KRAS gene knock down activity in MIA PaCa-2 cells in vitro, LNPK15/KRAS showed a strong anti-tumor efficacy in MIA PaCa-2 tumor xenograft mice after intravenous administration at 5mg/kg twice weekly. KRAS mRNA and protein knock down was observed in tumor tissue, suggesting on-target anti-tumor efficacy. In order to elucidate the in vitro-in vivo discrepancy, we performed ex vivo knock down assay using serum samples obtained after intravenous administration of LNPK15/KRAS to mice and monkeys. The collected samples were added to MIA PaCa-2 cells, and KRAS gene knock down was evaluated after a 24-h incubation period. The knock down efficacy was weak (≈20%) with serum samples at initial sampling point (2h), and it became much stronger (∼90%) with serum samples at later time points. Lipid composition of LNPK15 in the serum samples was also investigated. Among the five lipids incorporated in LNPK15, PEG-DSPE was degraded more rapidly than siRNA and the other lipids in both mice and monkeys. In vitro lipase treatment of LNPK15/KRAS also hydrolyzed PEG-DSPE and enhanced knock down activity. From these results, it was concluded that LNPK15 acquires increased knock down activity after undergoing PEG-DSPE hydrolysis in vivo, and that is the key mechanism to achieve both long circulation and potent knock down efficiency. We also proposed an in vitro assay system using lipase for quality control of LNP to ensure biological activity.

Accumulation of Liver Lipids Induced by Vitamin B6 Deficiency Was Effectively Ameliorated by Choline and, to a Lesser Extent, Betaine.

Despite previous studies suggesting that choline and betaine ameliorate lipid accumulation in rat livers, the relative effectiveness of the two nutrients is unclear. We examined the efficacy of dietary supplementation with choline or betaine in ameliorating lipid accumulation induced by vitamin B6 (B6) deficiency in the rat liver. Male Wistar rats were fed control, B6-deficient, choline-supplemented B6-deficient, betaine-supplemented B6-deficient, or both choline and betaine-supplemented B6-deficient diets (all containing 9 g of l-methionine (Met)/kg) for 35 d. Two experiments were performed, i.e., one using 17 mmol/kg diet choline bitartrate, betaine anhydrous, and the combination and another using 8.5 mmol/kg diet. Rats fed a B6-deficient diet developed lipid accumulation in the liver with a reduction of plasma lipids induced by the disruption of Met metabolism. However, the addition of 17 mmol/kg diet choline or betaine was sufficient to ameliorate the disruptions of lipid and Met metabolism. Additionally, 8.5 mmol/kg diet choline ameliorated liver lipid deposition, while the same amount of betaine had no significant effects on liver or plasma lipid profiles. Supplementation with choline resulted in a higher liver betaine than that found using the same amount of betaine alone, although the overall liver betaine content was reduced in B6-deficient rats. Our findings indicate that choline is more effective than betaine in ameliorating B6 deficiency-related disruptions in Met metabolism and liver lipid accumulation by increasing liver betaine levels.

Meteorological effects on severe hemoptysis: A hospital-based observational study.

BACKGROUND: Although some meteorological factor are likely to contribute to the onset of hemoptysis, few studies have investigated this issue, with none conducted in the Asia-Pacific region. Therefore, the present study aimed to evaluate the associations of meteorological factors with the occurrence of hemoptysis. Differences in the frequency of hemoptysis among several calendar variables were also assessed. METHODS: A total of 47 hemoptysis patients aged ≥ 20 years undergoing bronchial artery embolization in Kyushu Central Hospital of the Mutual Aid Association of Public School Teachers from January 2012 to December 2017 were included in the study. All hemoptysis events were assembled in a single time series, and the proportion of hemoptysis days was 2.1%. The associations of meteorological variables with hemoptysis days were estimated as odds ratios with 95% confidence intervals by using multivariable-adjusted logistic regression models. The frequency of hemoptysis days was compared among several calendar variables using a chi-square test. RESULTS: Mean relative humidity was negatively associated with hemoptysis (P for trend = 0.02). The inverse association remained significant when only the hemoptysis events with no infectious lung diseases were used (P for trend=0.02). No significant difference was observed in the occurrence of hemoptysis among seasons, months, or other calendar variables (all P ≥ 0.21). CONCLUSIONS: Lower relative humidity was a significant risk factor for the development of hemoptysis. Clinicians should be aware of the potential for increases in hemoptysis events on days with low ambient humidity.

A comparative study for detecting CYP3A induction by CYP3A probe drugs and endogenous markers in cynomolgus monkeys.

CYP3A probe drugs such as midazolam and endogenous markers, and plasma 4ß-hydroxycholesterol (4ß-OHC) and urinary 6ß-hydroxycortisol-to-cortisol ratios (6ß-OHC/C) have been used as markers of CYP3A induction in cynomolgus monkeys, as with humans. However, there is limited information on their sensitivity and ability to detect CYP3A induction, as most studies were evaluated only at a high dose of the inducer, rifampicin (RIF; 20 mg/kg). In the present study, the CYP3A induction by RIF over a range doses of 0.2, 2 and 20 mg/kg (n = 4) was examined using CYP3A probe drugs (midazolam, triazolam and alprazolam) and the plasma and urinary endogenous CYP3A markers (4ß-OHC and 6ß-OHC/C). The sensitivity and relationship for detecting CYP3A induction was compared among the markers. Four days repeated oral administration of rifampicin to cynomolgus monkeys reduced the area under the plasma concentration-time curve of all CYP3A probe drugs in a rifampicin dose-dependent manner. Although the endogenous CYP3A markers (4ß-OHC and 6ß-OHC/C) were also changed for the middle (2 mg/kg) and high (20 mg/kg) doses of rifampicin, the fold-changes were relatively small, and CYP3A induction could not be detected at the lowest dose of rifampicin (0.2 mg/kg). In conclusion, CYP3A probe drugs are more sensitive for detecting CYP3A induction than endogenous CYP3A markers in cynomolgus monkeys, even for a short experimental period.

Studies of CDK 8/19 inhibitors: Discovery of novel and selective CDK8/19 dual inhibitors and elimination of their CYP3A4 time-dependent inhibition potential.

In this article, synthetic studies around a pyridylacrylamide-based hit compound (1), utilizing structure-based drug design guided by CDK8 docking models, is discussed. Modification of the pendant 4-fluorophenyl group to various heteroaromatic rings was conducted aiming an interaction with the proximal amino acids, and then replacement of the morpholine ring was targeted for decreasing potential of time-dependent CYP3A4 inhibition. These efforts led to the compound 4k, with enhanced CDK8 inhibitory activity and no apparent potential for time-dependent CYP3A4 inhibition (CDK8 IC50: 2.5nM; CYP3A4 TDI: 99% compound remaining). Compound 4k was found to possess a highly selective kinase inhibition profile, and also showed favorable pharmacokinetic profile. Oral administration of 4k (15mg/kg, bid. for 2weeks) suppressed tumor growth (T/C 29%) in an RPMI8226 mouse xenograft model.

Design and synthesis of selective CDK8/19 dual inhibitors: Discovery of 4,5-dihydrothieno[3',4':3,4]benzo[1,2-d]isothiazole derivatives.

To develop a novel series of CDK8/19 dual inhibitors, we employed structure-based drug design using docking models based on a library compound, 4,5-dihydroimidazolo[3',4':3,4]benzo[1,2-d]isothiazole 16 bound to CDK8. We designed various [5,6,5]-fused tricyclic scaffolds bearing a carboxamide group to maintain predicted interactions with the backbone CO and NH of Ala100 in the CDK8 kinase hinge region. We found that 4,5-dihydrothieno[3',4':3,4]benzo[1,2-d]isothiazole derivative 29a showed particularly potent enzymatic inhibitory activity in both CDK8/19 (CDK8 IC50: 0.76nM, CDK19 IC50: 1.7nM). To improve the physicochemical properties and kinase selectivity of this compound, we introduced a substituted 3-pyridyloxy group into the scaffold 8-position. The resulting optimized compound 52h showed excellent in vitro potency (CDK8 IC50: 0.46nM, CDK19 IC50: 0.99nM), physicochemical properties, and kinase selectivity (only 5 kinases showed <35% unbound fraction at 300nM. CDK19: 4.6%, CDK8: 8.3%, HASPIN: 23%, DYRK1B: 27%, HIP1: 32%). Based on a docking model of 52h bound to CDK8, we could explain the highly specific kinase activity profile found for this compound, based on the interaction of the pyridyl group of 52h interacting with Met174 of the CDK8 DMG activation loop. In vitro pharmacological evaluation of 52h revealed potent suppression of phosphorylated STAT1 in various cancer cells. The high oral bioavailability found for this compound enabled in vivo studies, in which we demonstrated a mechanism-based in vivo PD effect as well as tumor growth suppression in an RPMI8226 human hematopoietic and lymphoid xenograft model in mouse [T/C: -1% (2.5mg/kg, qd)].

Effect of fibronectin adsorption on osteoblastic cellular responses to hydroxyapatite and alumina.

Initial cellular responses following implantation are important for inducing osteoconduction. We investigated cell adhesion, spreading, proliferation and differentiation of mouse MC3T3-E1 osteoblastic cells on untreated or fibronectin (Fn)-coated discs of hydroxyapatite (HAp) or alpha-type alumina (α-Al2O3). Fn coating significantly enhanced adhesion and spreading of MC3T3-E1 cells on HAp, but did not affect MC3T3-E1 cell proliferation and differentiation on HAp or α-Al2O3. Fn-coated HAp likely does not stimulate pre-osteoblast cells to initiate the process of osteoconduction; however, Fn adsorption might affect the response of inflammatory cells to the implanted material or, in conjunction with other serum proteins, stimulate pre-osteoblast cell proliferation and differentiation. Further studies on the effect of serum proteins in cell culture and the efficacy of Fn-coated HAp and α-Al2O3in vivo are warranted.

Fibronectin adsorption on osteoconductive hydroxyapatite and non-osteoconductive α-alumina.

The osteoconductivity mechanism of hydroxyapatite (HAp) has not been elucidated. It is hypothesized that specific proteins adsorb on HAp, promoting its osteoconductivity. To verify this hypothesis, we compared the adsorption behavior of fibronectin (Fn) on HAp powder and on α-alumina (α-Al2O3) powder, a material with no osteoconductivity. More Fn adsorbed on α-Al2O3 than on HAp, irrespective of the Fn concentration, and there was no significant difference in the secondary structure of Fn adsorbed on HAp and α-Al2O3. Further, it is possible that Fn did not adsorb on HAp and α-Al2O3 through the Arg-Gry-Asp motif of Fn. The amount of Fn adsorbed on HAp oriented to the a(b)-axis with very little decrease in carbonate and the adsorbed Fn had a smaller α-helix structure content. The results suggest that the secondary and/or higher-order structure rather than the amount of adsorbed Fn might affect the osteoconductivity of HAp, which might be electrostatically controlled by the crystal face orientation and/or carbonate content of HAp, although this should be confirmed by a cell culture test in the future.

Checkpoint Kinase 1 Activation Enhances Intestinal Epithelial Barrier Function via Regulation of Claudin-5 Expression.

Several stressors are known to influence epithelial tight junction (TJ) integrity, but the association between DNA damage and TJ integrity remains unclear. Here we examined the effects of daunorubicin and rebeccamycin, two anti-tumor chemicals that induce DNA damage, on TJ integrity in human intestinal epithelial cells. Daunorubicin and rebeccamycin dose-dependently enhanced transepithelial electrical resistance (TER) and decreased flux of the 4 kDa FITC-dextran in Caco-2 cell monolayer. Daunorubicin- or rebeccamycin-induced enhancement of the TJ barrier function partly rescued attenuation of the barrier function by the inflammatory cytokines TNF-α and IFN-γ. Daunorubicin and rebeccamycin increased claudin-5 expression and the product was distributed in the actin cytoskeleton fraction, which was enriched with TJ proteins. Caffeine, which is an inhibitor of ataxia telangiectasia mutated protein (ATM) and ataxia telangiectasia mutated and Rad3-related protein (ATR), and the Chk1 inhibitor inhibited the TER increases induced by daunorubicin and rebeccamycin, whereas a Chk2 inhibitor did not. Treatment with Chk1 siRNA also significantly inhibited the TER increases. Induction of claudin-5 expression was inhibited by Chk1 inhibitor and by siRNA treatment. Our results suggest that Chk1 activation by daunorubicin and rebeccamycin induced claudin-5 expression and enhanced TJ barrier function in Caco-2 cell monolayer, which suggests a link between DNA damage and TJ integrity in the human intestine.

IgE Abs to Der p 1 and Der p 2 as diagnostic markers of house dust mite allergy as defined by a bronchoprovocation test.

BACKGROUND: Limited information is available regarding the clinical usefulness of measuring the levels of IgE to allergen components from house dust mites (HDMs) in the diagnosis of genuine HDM allergy. METHODS: To evaluate the diagnostic usefulness of measuring levels of serum IgE antibodies (Abs) to allergen components from Dermatophagoides pteronyssinus (DP) as a predictor of immediate asthmatic response (IAR) to bronchoprovocation, we studied 55 DP-sensitized asthmatic patients who underwent a bronchoprovocation test using crude DP extract. The levels of IgE Abs to crude DP, nDer p 1, rDer p 2, and rDer p 10 in patients who showed IAR (n = 41) were compared with those in patients who showed no IAR (n = 14). RESULTS: While the frequencies of positivity for IgE Abs to nDer p 1 and rDer p 2 among the entire study population were 89 and 86%, respectively, all patients with IAR tested positive for both of them with high IgE concentrations. The areas under the receiver operating characteristic curves for IgE to nDer p 1 and rDer p 2 as predictors of IAR were 0.913 and 0.906, respectively. The specificity of IgE to nDer p 1 and rDer p 2 was higher than IgE to crude DP even at low cut-off points. CONCLUSIONS: IgE to nDer p 1 and/or rDer p 2 was highly predictive of allergen-induced IAR. These findings validate the clinical usefulness of measuring the levels of IgE to nDer p 1 and rDer p 2 as a diagnostic tool for genuine HDM allergy.

[Comparison of exhaled nitric oxide levels measured by two offline methods and the NO breath® method in Japan].

BACKGROUND: The fraction of exhaled nitric oxide (FeNO) is a useful marker of eosinophilic airway inflammation in asthmatics. Clinical application of FeNO measurement in Japan is expected increase because the procedure is now covered through health insurance. However, the measurement system used is known to affect FeNO results, and it remains unknown whether results from offline methods correlate with those from traditional online methods, such as NO breath®. METHODS: The study population comprised 48 patients at our hospital. FeNO levels were measured by using two offline methods (Sievers and CEIS) and a standard online method, NO breath® RESULTS: FeNONO breath levels were significantly correlated with FeNOSievers(r=0.875) and FeNOCEIS(r=0.888) levels. FeNONO breath levels were nearly equal to FeNOSievers results (FeNONO breath=1.05×FeNOSievers), but both of these levels were lower (p=0.02) than FeNOCEIS data (FeNONO breath=0.74×FeNOCEIS). A Bland-Altman plot of values obtained by the NO breath® and Sievers methods revealed that the NO breath® result was lower than the Sievers level when FeNO was low but was higher than the Sievers level when FeNO was high. CONCLUSION: Differences exist in the levels of FeNO measurement by three methods (two offline methods and NO breath®): conversion equations are needed to compare the FeNO levels obtained by using these three methods. In addition, NO breath® may be more useful to distinguish asthmatic patients from non-asthmatics, compared with Sievers method.

Effect of dalteparin, a low-molecular-weight heparin, as adjunctive therapy in patients with Kawasaki disease: a retrospective study.

BACKGROUND: Dalteparin, a low-molecular-weight heparin, has anticoagulant and anti-angiogenic activity. This study investigated whether dalteparin reduced coronary artery lesion (CAL) prevalence, and resistance to intravenous immunoglobulin (IVIG) therapy in Kawasaki disease (KD). METHODS: This retrospective study comprised two parts. In the first cohort, 126 patients with KD (68 male, 58 female; median age: 22 months, range: 1-67 months) admitted to Nihon University Nerima-Hikarigaoka Hospital from January 2004 to June 2008, received either dalteparin 75 IU/kg/day, IVIG 400 mg/kg/day for 5 consecutive days, and aspirin 30 mg/kg/day, or dalteparin 75 IU/kg/day and aspirin 30 mg/kg/day, until clinical improvement. Control data came from the 2005-6 Nationwide KD survey. In the second cohort, 112 patients with KD (59 male, 53 female; median age: 19 months, range: 1-66 months) admitted from June 2010 to February 2012, received either dalteparin 75 IU/kg/day, IVIG 2.0 g/kg over 12 h, and aspirin 30 mg/kg/day, or dalteparin 75 IU/kg/day and aspirin 30 mg/kg/day. Control data came from the 2009-10 Nationwide KD survey. No patients enrolled in the nationwide surveys received dalteparin. All patients at our institution were given dalteparin in their combination therapy. RESULTS: A comparison of the first cohort with controls in the nationwide survey showed that the prevalence of initial administration of IVIG was 80.2% versus 86.0%; the rate of additional IVIG administration was 7.1% versus 14.0% (p = 0.03); CAL prevalence in the acute period was 4.8% versus 11.9% (p < 0.01); and the prevalence of cardiovascular sequelae was 0% versus 3.8% (p < 0.05). A comparison of the second cohort with controls in the nationwide survey showed that the rate of initial administration of IVIG was 92.9% versus 89.5%; the rate of additional IVIG administration was 8.9% versus 17.1% (p = 0.02); the prevalence of resistance to IVIG was 3.6% versus 14.9% (p < 0.001); and CAL prevalence in the acute period was 2.7% versus 8.6% (p = 0.03). CONCLUSIONS: This study found that adjunctive dalteparin was associated with a lower prevalence of IVIG resistance and CAL in young children with KD. TRIAL REGISTRATION UMIN-CTR: UMIN000010349.

Development of vascular smooth muscle contractility by endothelium-derived transforming growth factor ß proteins.

It is well established that the release of vasodilators and vasoconstrictors from vascular endothelium regulates vascular smooth muscle contraction. In this report, we investigate the role of the endothelium in the development and maintenance of constitutive vascular contractility. For that purpose, contractile activity of cultured bovine aortic smooth muscle cells (BASMCs) embedded in collagen gels was monitored by changes in gel diameter. After culturing for 5 days, ATP- and high KCl solution-induced contractions were significantly enhanced in the gels that were overlaid with bovine aortic endothelial cells (BAECs) or were cultured with conditioned medium of cultured BAECs. ATP-induced Ca(2+) transients, recorded in BASMCs cultured with conditioned medium of BAECs, were markedly augmented, but high KCl-induced Ca(2+) transients were not affected. BASMCs in control gels were spindle shaped, and those in endothelium-treated gels were more elongated and interconnected. The endothelial conditioned medium also strongly affected the intracellular distribution of actin fibers. Conditioned medium of BAECs contained TGFß1 and TGFß2. The TGFß receptor antagonist SB431542 as well as simultaneous treatment with TGFß1 and TGFß2 neutralizing antibodies completely reversed the above effects of endothelial conditioned medium on BASMCs. BAECs medium induced phosphorylation of Smad2 and increased ATP-induced phosphorylation of myosin light chain in BASMCs. The present results indicate that the release of TGFß1 and TGFß2 from vascular endothelium affects the contractility of vascular smooth muscle cells by altering their morphology and agonist-induced Ca(2+) mobilization.

Cough variant and cough-predominant asthma are major causes of persistent cough: a multicenter study in Japan.

OBJECTIVE: Persistent cough is a frequent cause of doctor and hospital visits, and its incidence may be increasing. However, diagnosis of the cause of cough remains difficult. Because different causes of cough have different treatments, accurate diagnosis of the cause of cough is critical. To gain a better understanding of the causes of cough in Japan, we performed a multicenter epidemiological study of Japanese patients. METHODS: The study involved seven institutions in five different areas of Japan, and was conducted over 1 year from March 2009. Patients aged ≥16 years attending the participating centers for the first time complaining of cough persisting for ≥3 weeks were eligible. Patients with chest X-ray abnormalities responsible for cough, fever or blood-stained sputum were excluded, while those with wheeze or shortness of breath were included. Frequency and severity of cough were assessed using questionnaires, and laboratory tests were performed to enable differential diagnoses. RESULTS: Among the 313 patients evaluated, mean duration of cough symptoms was 192.1 ± 558.4 days. Cough variant asthma (CVA) was the most common cause of prolonged/chronic cough (42.2%), followed by cough-predominant asthma (CPA) (28.4%), atopic cough (7.3%) and chronic obstructive pulmonary disease (6.7%). Patients with an unclear diagnosis were treated with tulobuterol, a transdermal ß2-agonist preparation, for 1-2 weeks. Transdermal tulobuterol improved assessments of cough in patients with CVA or CPA, enabling rapid diagnosis of these diseases. CONCLUSIONS: These findings show that CVA and CPA are the main causes of cough persisting for ≥3 weeks.

Age-specific characteristics of inpatients with severe asthma exacerbation.

BACKGROUND: The characteristics of inpatients with severe asthma exacerbation remain unclear. It is considered that the characteristics of inpatients with severe asthma vary depending on age. However, these are rarely investigated. The objective of this study is to investigate the differences in characteristics among different age groups. We considered that it is necessary to understand the characteristics of each age group so that we can establish strategies in preventing severe asthma exacerbation. METHODS: All asthma inpatients who were hospitalized between 2004 and 2011 with SpO2 <90% (in room air), were breathless at rest, and showed increased respiratory rate and pulse rate were examined. We compared the characteristics among the young age group, middle age group, and advanced age group. RESULTS: The total number of patients was 204. In the young age group, the percentages of patients with irregular visits and non visits to a medical institution were high. This group showed high percentages of smokers and pet owners. The percentage of continuous ICS users in this group was 25.9%. The middle age group had high rates of aspirin-intolerant asthma. The percentage of continuous ICS users in this group was 60.2%. In the advanced age group, the percentages of patients with hypertension/heart disease, diabetes mellitus, and COPD were high. This group showed good treatment adherence. The percentage of continuous ICS users in this group was 77.4%. CONCLUSIONS: The characteristics of inpatients with severe asthma vary depending on age. We need to establish countermeasures for asthma exacerbation according to the characteristics of patients depending on age.

Oxidative addition of a strained C-C bond onto electron-rich rhodium(I) at room temperature.

The C-C bond of cyclobutanones undergoes oxidative addition to a T-shape rhodium(I) complex possessing a PBP pincer ligand at room temperature. The remarkable propensity of the rhodium complex for oxidative addition is attributed to the highly electron-donating nature of the boron ligand as well as the unsaturation on the rhodium center.

Glycemic control after addition of the dipeptidyl peptidase-4 inhibitor alogliptin in patients with type 2 diabetes showing inadequate response to thrice-a-day treatment with α-glucosidase inhibitors.

OBJECTIVE: We investigated the effect of addition of alogliptin, while continuing the α-glucosidase inhibitor (αGI) administration at the same or reduced dose, or discontinuing the drug, on the glycemic control in type 2 diabetic patients showing inadequate response to αGI treatment. RESEARCH DESIGN AND METHODS: A prospective, randomized, controlled, multicenter interventional study trial. Subjects were randomly assigned to treatment with alogliptin alone (Intake 0 group), or alogliptin in addition to an αGI administered once-/twice-/thrice-daily (Intake 1, 2 and 3 groups). MAIN OUTCOME MEASURES: Changes in glycemic control were measured. RESULTS: The HbA1c and glycoalbumin levels at 1 and 3 months were significantly lower than the values at the baseline in the Intake 1, 2 and 3 groups, but not the Intake 0 group. The body weight at 3 months was significantly lower than that at the baseline in the Intake 3 group. There were no significant differences in the degree of satisfaction or participating volition recorded, before and after the start of the study treatments. CONCLUSIONS: Addition of alogliptin to once-/twice-daily administration of an αGI may be effective for obtaining improved glycemic control, without lowering the treatment satisfaction level, in type 2 diabetic patients.

A 4-year-old girl with clinically mild encephalopathy with a reversible splenial lesion associated with rotavirus infection.

Rotavirus is a common cause of severe gastroenteritis in children. It is known that rotavirus gastroenteritis may be accompanied by neurological manifestations, including encephalitis/encephalopathy and seizures. We report a case of a 4-year-old girl with clinically mild encephalopathy with a reversible splenial lesion associated with rotavirus infection. She was admitted to our hospital because of reduced level of consciousness, seizures, diarrhea, and vomiting. Fecal rotavirus antigen testing was positive. Cell counts in the cerebrospinal fluid (CSF) were normal. She had a normal serum sodium level on admission. Brain computed tomography showed no cerebral edema. However, electroencephalography showed generalized high-voltage slow waves, and diffusion-weighted magnetic resonance imaging demonstrated a transient abnormality in the splenium of the corpus callosum. We diagnosed clinically mild encephalopathy with a reversible splenial lesion associated with rotavirus infection. She recovered well and exhibited no neurological sequelae. Rotavirus RNA and antigen were not detected in the CSF, suggesting that the reversible splenial change was caused by indirect effects on the central nervous system subsequent to viral infection. Her normal serum sodium level indicates that this change can occur without hyponatremia.

Acute encephalopathy with pandemic (H1N1) 2009 virus infection.

OBJECTIVES: In April 2009, a novel influenza A (H1N1) pdm virus was identified in Mexico and spread quickly around the world. However, the clinical features of acute encephalopathy associated with 2009 pandemic influenza have not yet been elucidated. METHODS: We treated 8 patients (3 boys and 5 girls) aged 4 to 11 years (average age, 8 y 3 months) with influenza virus-associated encephalopathy, who presented at our 2 hospitals between July 2009 and March 2010. We investigated the clinical characteristics, treatments, and outcomes in the patients. RESULTS: In all patients, brain computed tomography showed mild to severe diffuse cerebral edema, and electroencephalography revealed diffuse high-voltage slow waves. They were all treated with oseltamivir and methylprednisolone pulse therapy. Six patients recovered without any sequelae; however, the remaining 2 had residual neurological sequelae. These 2 patients presented with severe disturbance of consciousness, and their central nervous system symptoms appeared within 12 hours after the onset of fever. One patient had periventricular leukomalacia and symptomatic epilepsy by perinatal brain hypoxia, and the other patient had 1 complex febrile and 2 febrile seizures. CONCLUSIONS: This study showed that patients with influenza-associated encephalopathy caused by influenza A (H1N1) pdm infection were all older than those with seasonal influenza. Underlying neurological disease or history may be associated with poor prognosis.

Rapid effectiveness of minocycline or doxycycline against macrolide-resistant Mycoplasma pneumoniae infection in a 2011 outbreak among Japanese children.

BACKGROUND: Mycoplasma pneumoniae is a major pathogen causing community-acquired pneumonia in children and young adults. Outbreaks typically occur at intervals of several years. In 2011, a widespread outbreak was associated with macrolide-resistant M. pneumoniae (MRMP) in Japanese children, often those of school age. METHODS: Two hundred fifty-eight children were diagnosed with M. pneumoniae-associated pneumonia based on chest radiography, real-time polymerase chain reaction (PCR), and antibody titers between January and December 2011. Mycoplasma pneumoniae cultures obtained from nasopharyngeal samples using appropriate broth were subjected to real-time PCR, by which decreases in M. pneumoniae in patients treated with minocycline (MIN), doxycycline (DOX), or tosufloxacin (TFX) were calculated. Mutations of the 23S ribosomal RNA gene that confer high resistance to macrolides in M. pneumoniae were identified by DNA sequencing. RESULTS: Among 202 M. pneumoniae isolates from M. pneumoniae-associated pneumonia patients, 176 (87.1%) were MRMP. Macrolide-resistant M. pneumoniae infection was significantly related to school age (P < .01) and initial administration of macrolides (P < .01). Minocycline or DOX (n = 125) or TFX or levofloxacin (n = 15) was used for definitive treatment of MRMP patients. Minocycline or DOX was significantly more effective than TFX (P ≤ .05) in achieving defervescence within 24 hours and in decreasing numbers of M. pneumoniae DNA copies 3 days after initiation. CONCLUSIONS: Macrolides are inappropriate as first-choice agents against MRMP in terms of shortening the clinical course and decreasing M. pneumoniae. Control and prevention of MRMP outbreaks in children require early decreases in M. pneumoniae as well as improvement of clinical findings.