Involvement of the glutamate transporter and the sodium–calcium exchanger in the hypoxia-induced increase in intracellular Ca in rat hippocampal slices

Hippocampal slices prepared from adult rats were loaded with fura-2 and the intracellular free Ca²⁺ concentration ([Ca²⁺]_i) in the CA1 pyramidal cell layer was measured. Hypoxia (oxygen–glucose deprivation) elicited a gradual increase in [Ca²⁺]_i in normal Krebs solution. At high extracellular sodium concentrations ([Na⁺]_o), the hypoxia-induced response was attenuated. In contrast, hypoxia in low [Na⁺]_o elicited a significantly enhanced response. This exaggerated response to hypoxia at a low [Na⁺]_o was reversed by pre-incubation of the slice at a low [Na⁺]_o prior to the hypoxic insult. The attenuation of the response to hypoxia by high [Na⁺]_o was no longer observed in the presence of antagonist to glutamate transporter. However, antagonist to Na⁺–Ca²⁺ exchanger only slightly influenced the effects of high [Na⁺]_o. These observations suggest that disturbance of the transmembrane gradient of Na⁺ concentrations is an important factor in hypoxia-induced neuronal damage and corroborates the participation of the glutamate transporter in hypoxia-induced neuronal injury. In addition, the excess release of glutamate during hypoxia is due to a reversal of Na⁺-dependent glutamate transporter rather than an exocytotic process.     

Pharmacokinetics and Safety of Triple Therapy with Vonoprazan,Amoxicillin, and Clarithromycin or Metronidazole: A Phase 1, Open-Label,Randomized, Crossover Study

Introduction

Vonoprazan (TAK-438) is a novel potassium-competitive acid blocker that inhibits gastric H⁺, K⁺-ATPase. The objectives of this study were to evaluate the influence of triple therapy with vonoprazan–amoxicillin–clarithromycin or vonoprazan–amoxicillin–metronidazole on the pharmacokinetics of each component of the triple therapies (primary) and to evaluate the safety and tolerability of vonoprazan-based triple therapies (secondary) in healthy adults.

Methods

In this single-center, phase 1, open-label, randomized, four-way crossover study, Helicobacter pylori-negative, healthy Japanese male subjects were randomly assigned to 1 of 4 treatment sequences in two cohorts (12 subjects per cohort). Each treatment sequence comprised four treatment periods separated by a washout period of 7 or 14 days. Pharmacokinetic parameters for vonoprazan, amoxicillin, clarithromycin and metronidazole in single therapy or triple therapies were assessed. All adverse events were recorded.

Results

Compared with single therapy, triple therapy with vonoprazan–amoxicillin–clarithromycin increased the area under the plasma concentration–time curve from time 0–12 h (AUC_0-12) and maximum plasma concentration (C _max) of plasma vonoprazan free base by 1.846- and 1.868-fold, respectively, and increased the AUC_0-12 and C _max of plasma clarithromycin by 1.450- and 1.635-fold, respectively. Triple therapy with vonoprazan–amoxicillin–metronidazole had no influence on the pharmacokinetics of vonoprazan or metronidazole. The pharmacokinetics of amoxicillin was not influenced by vonoprazan-based triple therapies. Seven adverse events were reported. Two subjects discontinued because of an adverse event (rash, liver function test abnormal); both events were considered to be study drug-related.

Conclusion

In healthy Japanese male subjects, triple therapy with vonoprazan–amoxicillin–clarithromycin increased vonoprazan and clarithromycin exposure. The safety and tolerability profile of triple therapy with vonoprazan–amoxicillin–clarithromycin or vonoprazan–amoxicillin–metronidazole was favorable in this population.

Funding

Takeda Pharmaceutical Company Ltd.

Trial registration

JapicCTI-153102.

     

Induction of interstitial pneumonitis during interferon treatment for chronic hepatitis C

A 48-year-old woman developed interstitial pneumonitis while receiving interferon treatment for chronic hepatitis C. Laboratory studies prior to treatment showed elevated serum alanine aminotransferase levels, but chest X-rays and physical examination revealed no abnormalities suggestive of interstitial pneumonitis. At the 9th week of interferon treatment (total dose, 380MU of recombinant interferon-α, without other medications), the patient began to complain of cough and exertional dyspnea. A chest X-ray film revealed diffuse reticulo-nodular shadows in bilateral lung fields, suggesting a diagnosis of interstitial pneumonitis. A marked increase in lymphocyte count was observed in bronchoalveolar lavage fluid and a diagnosis of interstitial pneumonitis was made as a result of transbronchial lung biopsy. Her clinical symptoms and abnormal lung shadows were reversible, improving within a month of the discontinuation of interferon, and disappearing promptly after exogenous corticosteroid was instituted. This may be the first case of drug-induced interstitial pneumonitis occurring during the course of treatment with interferon alone. We should be aware of the possibility of interstitial pneumonitis developing during treatment of chronic hepatitis C with interferon.     

Contradictory Responses to the COVID-19 Pandemic in Amyotrophic Lateral Sclerosis Patients and Their Families and Caregivers in Japan

Objective The coronavirus disease 2019 (COVID-19) pandemic has resulted in a shortage of medical resources, including ventilators, personal protective equipment, medical staff, and hospital beds. We investigated the impact of COVID-19 in amyotrophic lateral sclerosis (ALS) patients, their families, caregivers, and medical experts. Methods We conducted a nationwide ALS webinar about COVID-19 in May 2020 and sent a questionnaire to those enrolled. Results A total of 135 participants (31 ALS patients; 23 families and caregivers of ALS patients; 81 medical experts) responded to this cross-sectional self-report questionnaire. The results showed that tracheostomy and invasive ventilation (TIV) was used in 22.6% of ALS patients, whereas 77.4% of ALS patients were not under TIV. Among non-TIV patients (n=24), 79.2% did not want TIV in the future. However, 47.4% of non-TIV patients not wanting a tracheostomy in advanced stages replied that they would want an emergency tracheostomy if they developed COVID-19-related pneumonia. These results suggest that ALS patients may be receptive to emergency treatments for reasons other than ALS. In addition, approximately half of the ALS patients agreed with the policy of not ventilating the elderly or ALS patients in case of a ventilator shortage. Furthermore, compared with medical experts, few ALS patients reported that the chance for ALS patients to obtain work was higher due to the increasing availability of remote work. Conclusions This survey indicates that the COVID-19 pandemic might be associated with increased distress about access to care and work, inducing contradictory responses and potential hopelessness among ALS patients.     

Examination of tumor diameter measurement precision by RECIST

Image evaluation with Response Evaluation Criteria in Solid Tumors (RECIST) evaluates the change in a measurable lesion as determined by ruler or micrometer caliper. However, there is no definition of the conditions thought to influence the precision of measurement. We therefore examined the effects on measurement precision by changing image amplification, WW, WL, and time phase. Moreover, to determine response rate, one-dimensional evaluation with RECIST was compared with the two-dimensional evaluation of World Health Organization (WHO) for a hepatocellular carcinoma. The results of measuring the object lesion for measured value variation were as follows. Under image conditions of 1 time expansion/ WW 150/ WL 100 was (4.92+/-1.94)%. Under image conditions of 1 time expansion/ WW 350/ WL 75 was (4.42+/-1.70)%. Under image conditions of 4 times expansion/ WW 150/ WL 100 was (2.52+/-0.82)%. Under image conditions of 4 times expansion/ WW 350/ WL 75 was (2.83+/-1.10)%. When an image was enlarged to 4 times, precision doubled. There was no a difference in comparing RECIST to WHO in terms of response rate. Thus the best method was considered to be RECIST because of its convenience.     

A case of ectopic ureterocele in a male adult found during examination of a traumatic injury

We report a case of ectopic ureterocele in a male adult found during examination of a traumatic injury. A 26-year-old man sustained a blow to his left back during a football game and was admitted to the hospital with a complaint of abdominal pain. The computed tomographic scan showed a huge cystic mass in the retroperitoneum. A cystoscope revealed a large bulge from the left ureteral orifice to the bladder neck and another ureteral orifice distal to the bulge. Retrograde pyelography revealed an ectopic ureterocele showing a complete duplication, a lateral deviation of the left ureter and a bladder deviation to the right. An ectopic ureteral orifice was opening in the posterior urethra. An ureteral catheter inserted into this orifice revealed a dilated left ureter from the upper half of the kidney. Because the function of left upper of kidney was maintained, a transurethral incision was performed. Vesicoureteral reflux remained, but the postoperative course was uneventful. We discuss 11 cases of ectopic ureterocele in male adults including this case.     

Monotherapy for Childhood Epilepsies with Zonisamide

Abstract: Zonisamide was tried on 44 children, 18 girls and 26 boys, from 8 months to 15 years of age at the start of the trial. In 6 children the drug has been stopped because of side effects. The drug was introduced at a dose of 2–4 mg/kg/day and increased to 12 mg/kg/day unless a satisfactory response occurred at a lower dose. A 100% control of seizures was achieved in 5 of 5 cases of idiopathic generalized epilepsies, in 7 of 8 cases of symptomatic generalized epilepsies, in one of one case of idiopathic partial epilepsies, and in 17 of 24 cases of symptomatic partial epiSepsies. The main side effect was drowsiness, especially during the introduction.