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Thermal neutrons generated in the body during proton beam therapy (PBT) can be used to cause boron neutron capture reactions and have recently been proposed as neutron capture enhanced PBT (NCEPBT). However, the cell killing effect of NCEPBT remains underexplored. Here, we show an increase in the cell killing effect of NCEPBT. Using Monte Carlo simulations, we showed that neutrons generated by proton beam irradiation are uniformly spread on tissue culture plates. Human salivary gland tumor cell line (HSG), human osteosarcoma cell line (MG63), human tongue squamous cell carcinoma cell line (SAS), and human malignant melanoma cell line (G-361) were irradiated with X-rays, proton beams, and proton beams with 10 B-enriched boronophenylalanine (boron concentration of 20 and 80 ppm). The relative biological effectiveness (RBE) values of proton beams alone, proton beams with 20 ppm boron, and proton beams with 80 ppm boron for HSG, MG63, SAS, and G-361 were 1.02, 1.07, and 1.23; 1.01, 1.08, and 1.44; 1.05, 1.09, and 1.46; and 1.04, 1.13, and 1.63, respectively. NCEPBT with high boron concentration showed high RBE and a high sensitizing effect. Our results confirm an increase in the cell killing effect of NCEPBT, should aid in its clinical use, and warrant its further investigation., Competing Interests: Declarations Competing interests Boronophenylalanine used in this study was provided by Stella Pharma Corporation (Japan). Tatsuya Ohno received research funding from Hitachi. All other authors declare no conflict of interest., (© 2024. The Author(s).)

This research aimed to identify materials capable of emitting visible light useful for dose management at ultra-high dose rate (uHDR). Various materials were irradiated with proton beams at a normal dose rate (NDR) and uHDR, and the resulting surface luminescence was captured using a high-sensitivity camera. The luminescence images were compared with the corresponding dose distributions. The luminescence of Tough Water Phantoms (Kyoto Kagaku Co. Ltd.) with various thicknesses was also observed to evaluate the depth distributions. Dose distributions were measured using two-dimensional ionization chamber detector arrays. The Tough Bone Phantom (Kyoto Kagaku Co. Ltd.) exhibited the strongest luminescence among the materials, followed by the Tough Water Phantom. The metals exhibited relatively weak luminescence. The luminescence profiles of the Tough Water Phantom, water, the Tough Lung Phantom (Kyoto Kagaku Co. Ltd.), and an acrylic were similar to the dose profiles. The luminescence distribution of the Tough Water Phantom in the depth direction was similar to that of the dose distributions. The luminescence at uHDR and NDR were approximately equivalent. The Tough Water Phantom was found to be a suitable material for dosimetry, even at uHDR. More detailed measurement data, such as wavelength data, must be collected to elucidate the luminescence mechanism., (© 2024. The Author(s).)

Delivery time factor (DTF) is a new parameter introduced by the RayStation treatment planning system for tomotherapy treatment planning. This study investigated the effects of this factor on various tomotherapy plans. Twenty-five patients with cancer (head and neck, 6; lung, 9; prostate, 10) were enrolled in this study. Helical tomotherapy plans with a field width of 2.5 cm, pitch of 0.287, and DTF of 2.0 were created. All the initial plans were recalculated by changing the DTF parameter from 1.0 to 3.0 in increments of 0.1. Then, DTF's impact on delivery efficiency and plan quality was evaluated. Treatment time and modulation factor increased monotonically with increasing DTF. Increasing the DTF by 0.1 increased the treatment time and modulation factor by almost 10%. This relationship was similar for all treatment sites. Conformity index (CI), homogeneity index, and organ at risk doses were improved compared to plans with a DTF of 1.0, except for the CI in the lung cancer case. However, the improvement in most indices ceased at a certain DTF; nevertheless, treatment time continued to increase following an increase in DTF. DTF is a critical parameter for improving the quality of tomotherapy plans., (© 2023. The Author(s).)

Evaluation of feasibility and safety of percutaneous radiofrequency ablation using bipolar radiofrequency devices in a prospective multicenter cohort of patients with benign aldosterone-producing adenoma. A total of five institutions participated. CT-guided percutaneous RFA was performed for patients diagnosed as APA. The safety of the procedure was evaluated using the Common Terminology Criteria for Adverse Events. During the 84-day follow-up period, serial changes in plasma aldosterone concentration and plasma renin activity were measured. The percentage of patients with normalized hormonal activity after the procedure, was calculated with 95% confidence intervals. Forty patients were enrolled, and two patients were excluded for cerebral hemorrhage and no safe puncture root. In another patients, RFA was tried, but an intraprocedural intercostal arterial injury occurred. Consequently, RFA was completed in thirty-seven patients (20 men, 17 women; mean age, 50.4 ± 10.0 year). The tumor size was 14.8 ± 3.8 mm. The treatment success rate of the ablation was 94.6% (35/37), and a 2nd session was performed in 2.7% (1/37) patients. Grade 4 adverse events were observed in 4 out of 38 sessions (10.5%). The normalization of plasma aldosterone concentration or aldosterone-renin ratio was 86.5% (72.0-94.1: 95% confidence interval) on day 84. Percutaneous CT-guided RFA for APA using a bipolar radiofrequency system was safe and feasible with clinical success rate of 86.5% on day 84., (© 2022. The Author(s).)

Mineralocorticoid receptor (MR) blockers are very beneficial for patients with hypertension and primary aldosteronism (PA). We investigated the efficacy and safety of a newly available nonsteroidal MR blocker, esaxerenone, in Japanese patients with hypertension and PA. A multicenter, open-label study was conducted in Japan between October 2016 and July 2017. Patients with hypertension and PA received 12 weeks of treatment with esaxerenone, initiated at 2.5 mg/day and escalated to 5 mg/day during week 2 or 4 of treatment, based on individual response. The only other permitted antihypertensive therapies were stable dosages of a Ca 2+ channel blocker or α-blocker. The primary efficacy outcome was a change in sitting systolic and diastolic blood pressure (SBP/DBP) from baseline to the end of treatment. Forty-four patients were included; dose escalation to 5 mg/day was implemented for 41 of these patients. Significant decreases in SBP and DBP were observed (point estimates [95% confidence interval] -17.7 [-20.6, -14.7] and -9.5 [-11.7, -7.3] mmHg, respectively; both p < 0.0001 at the end of treatment). Significant BP reductions were evident from week 2 and continued through to week 8; BP remained stable until week 12. The antihypertensive effect of esaxerenone on SBP was significantly greater in females and in patients receiving monotherapy. The major drug-related adverse events were serum K + increase and estimated glomerular filtration rate decrease (both 4.5%, n = 2); no gynecomastia or breast pain was observed. We conclude that esaxerenone is a potent MR blocker with favorable efficacy and safety profiles in patients with hypertension and PA.

The mouse olfactory mucosa is a complex chemosensory tissue composed of multiple cell types, neuronal and non-neuronal. We have here applied RNA-seq hierarchically, in three steps of decreasing cellular heterogeneity: starting with crude tissue samples dissected from the nose, proceeding to flow-cytometrically sorted pools of mature olfactory sensory neurons (OSNs), and finally arriving at single mature OSNs. We show that 98.9% of intact olfactory receptor (OR) genes are expressed in mature OSNs. We uncover a hitherto unknown bipartition among mature OSNs. We find that 19 of 21 single mature OSNs each express a single intact OR gene abundantly, consistent with the one neuron-one receptor rule. For the 9 single OSNs where the two alleles of the abundantly expressed OR gene exhibit single-nucleotide polymorphisms, we demonstrate that monoallelic expression of the abundantly expressed OR gene is extremely tight. The remaining two single mature OSNs lack OR gene expression but express Trpc2 and Gucy1b2. We establish these two cells as a neuronal cell type that is fundamentally distinct from canonical, OR-expressing OSNs and that is defined by the differential, higher expression of 55 genes. We propose this tiered experimental approach as a paradigm to unravel gene expression in other cellularly heterogeneous systems.

Patients with poorly controlled hypertension despite taking at least three different kinds of anti-hypertensive drugs, including diuretics, are considered to have resistant hypertension (RH). The prevalence of RH was reported to be 13% in the Japanese J-HOME study. The incidences of RH in younger and older Japanese individuals should be prospectively investigated in the near future. RH is associated with poor outcomes and various cardiovascular events. In addition, it is frequently associated with older age, obesity, sleep apnea, long-term hypertension, diabetes, dyslipidemia, reduced renal function, microalbuminuria and left ventricular hypertrophy. Some cases of RH exhibit high levels of aldosterone and cortisol, suggesting that endocrine hypertension should be ruled out among RH patients. Carotid baroreceptor activation and renal sympathetic denervation have recently been developed as treatments for RH. In conclusion, we should consider the possibility of RH during the treatment of hypertensive patients who do not achieve appropriate blood pressure control, in order to avoid the early onset of fatal cardiovascular events and reduce medical costs.

Primary aldosteronism (PA) due to aldosterone-producing adenoma (APA) is a form of surgically curable secondary hypertension, and distinguishing APA from idiopathic hyperaldosteronism (IHA) is important for treatment. We made a differential diagnosis between APA and IHA using imaging tests such as adrenal CT and MRI as well as adrenal venous sampling (AVS) in all 93 cases of PA presenting at our institutions over the last decade. We identified 27 patients with aldosterone-producing microadenoma (APmicroA), all of whom could be diagnosed by AVS but not by the imaging tests. Then, we compared the clinical and roent-genological findings of these 27 patients with those of 42 patients with aldosterone-producing macroadenoma (APmacroA) and of 24 patients with IHA. Using surgically removed adrenal tissues, histopathological examinations and immunohistochemical analyses of steroidogenic enzymes were conducted. The findings for APmicroA were similar to those for APmacroA, except with respect to the diameter of the adrenal adenomas. Endocrinological and roentgenological findings for APmicroA were similar to those for IHA, but not to those for APmacroA. The rate of cure of hypertension was much greater in patients with APmicroA than in patients with APmacroA after the unilateral adrenalectomy (odds ratio, 4.0; p=0.028). In conclusion, it is important to accurately diagnose APmicroA, in which the laterality of the hyperproduction of aldosterone is only detectable by AVS, and to treat these patients by unilateral adrenalectomy in order to avoid long-term medical treatment and prevent hypertensive vascular complications.

Secondary hypertension (SH) including endocrine hypertension has been reported to be uncommon. We estimated the prevalence of SH among hypertensive patients. We prospectively studied 1,020 hypertensive patients. As an initial screening, we measured plasma aldosterone concentration, plasma renin activity, serum cortisol concentration and plasma catecholamine concentration and conducted abdominal ultrasonography (US). As a secondary screening, we performed furosemide plus upright test, captopril renography, dexamethasone suppression test, 24-h urine catecholamine measurement and abdominal CT. Finally, primary aldosteronism with the exception of idiopathic hyperaldosteronism, pheochromocytoma, and Cushing's syndrome were diagnosed by histopathological examination of surgical specimens. Idiopathic hyperaldosteronism was clinically diagnosed by adrenocorticotrophic hormone (ACTH)-stimulated adrenal venous sampling and renovascular hypertension by renal arteriography. There were 61 patients with primary aldosteronism, 5 with renovascular hypertension, 11 with Cushing's syndrome, 10 with preclinical Cushing's syndrome and 6 with pheochromocytoma, and the prevalence of SH was 9.1% among 1,020 hypertensive patients. In 76 (82%) of 93 patients with SH, hypertension was cured or improved after unilateral adrenalectomy, transsphenoidal pituitary adenectomy or percutaneous transluminal angioplasty. With the exception of US and CT, all initial and secondary screening tests were found to be sensitive and specific for differentiating SH from essential hypertension (EH). In conclusion, the measurement of various hormone concentrations was very sensitive for ruling out SH--a condition for which, in the present study, there were few specific signs or symptoms--while CT and US examinations were not always useful for differentiating SH from EH. The prevalence of curable SH among hypertensive subjects was higher in this study, which was conducted by our simple method of screening tests, than in previous reports. Hypertensive patients should be screened for SH and the underlying disease treated appropriately to avoid long-term use of antihypertensive drugs and risks of atherosclerotic complications.