Online Adaptive Radiotherapy for Pharyngeal Cancer: Dose-Volume Histogram Analysis between Adapted and Scheduled Plan

PURPOSE/OBJECTIVE(S)

The present study aimed to evaluate whether online adapted plan with artificial intelligence (AI) driven work flow could be used in clinical settings with variable changes of the targets and organs at risk (OARs) for pharyngeal cancer.

MATERIALS/METHODS

Ten patients with pharyngeal cancer who underwent chemoradiotherapy at our institution between January and July 2020 were included for the analysis. All patients had been previously aligned daily with cone-beam computed tomography (CBCT) and treated by O-ring Linac. A simulated treatment was performed on the treatment emulator. Weekly fractions, once in every 4-5 fractions, were simulated in the treatment emulator for each patient using their previous on-treatment CBCTs. The dataset was divided into three groups according to the treatment period (1st-2nd week, 20 CBCTs), middle (3rd-4th week, 20 CBCTs), and late (5th-7th week, 30 CBCTs) period. In the present study, all of reference plan generation in treatment emulator were created on the initial plans of two-step method using 12 equidistant field IMRT. The prescribed dose was 70 Gy in 35 fractions and normalized to the dose of 68.6 Gy (98% dose) to 95% of the planning target volume (PTV). The adaptation process on treatment emulator includes auto-segmentation of daily anatomy, calculation of the dose in scheduled plans using the same monitor units and optimization and calculation of the dose in adapted plan. Dose-volume histogram (DVH) parameters between adapted and scheduled plans in terms of PTV (D98%, D95%, D50% and D2%), spinal cord (Dmax and D1cc), brain stem (Dmax), ipsilateral and contralateral parotid glands (Dmedian and Dmean) were evaluated in each period.

RESULTS

D98% of PTV of adapted plan was significantly higher than that of scheduled plan in early and middle period (p = 0.02 and <0.01, respectively). D95% of PTV of adapted plan was significantly higher than that of scheduled plan in all periods (p<0.01). D2% of PTV of adapted plan was significantly lower than that of scheduled plan in all periods (p = 0.04, 0.04 and 0.02 in each period, respectively). There was not significant difference in D50% of PTV between adapted and scheduled plan in all periods. In terms of OARs, Dmax of spinal cord of adapted plan was significantly lower than that of scheduled plan in all periods (p<0.01). Similarly, D1cc of spinal cord of adapted plan was lower than that of scheduled plan. Dmean of ipsilateral and contralateral parotid glands of adapted plan were lower than those of scheduled plan in the late period (p<0.01 and 0.03, respectively).

CONCLUSION

The present study revealed that adapted plan with AI driven work flow could create dosimetrically better plans for pharyngeal cancer compared to scheduled plan. It was suggested that online adaptive radiotherapy could be necessary to maintain PTV coverage while reducing the dose to OARs in all periods for pharyngeal cancer.

POS1196 SARS-CoV-2 VACCINE ACCEPTANCE AND ASSOCIATED PSYCHOLOGICAL FACTORS IN PATIENTS WITH RHEUMATIC AND MUSCULOSKELETAL DISEASES

Background

The mortality rate of coronavirus disease 2019 (COVID-19) in patients with rheumatic and musculoskeletal disease (RMD) is as high as approximately 10% [1]. Therefore, vaccination promotion is a critical issue. However, there are few reports on the psychological aspects of patient vaccine acceptance.

Objectives

To investigate the intention of patients with RMD to receive the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccine and explore the psychological factors related to vaccine acceptance.

Methods

We conducted a questionnaire-based survey of 406 outpatients with RMD at Shiga General Hospital from July to October 2021. The questionnaire included the following sections: (1) vaccination status; (2) expectation of susceptibility to severe COVID-19; (3) expectation of vaccine efficacy; and (4) anxiety about the vaccine, which included concerns on I) the diminishing effect of the vaccine due to current treatment and II) the influence of vaccination on: i) primary disease status, ii) treatment, and iii) adverse reaction.

Results

There were 305 vaccinated and 101 unvaccinated individuals. Unvaccinated individuals were classified into the acceptance group (n=60) and hesitancy group (n=41) according to their vaccination status (Figure 1).

Figure 1.

SARS-CoV-2 vaccination status (n=406)

We compared the backgrounds and awareness of the patients on vaccination between the two groups. Univariate analysis did not show any difference in the backgrounds. The expectation of susceptibility to severe COVID-19 was similar in both groups. There were also no significant differences in the vaccine-related anxiety levels. However, the expectation of vaccine efficacy was higher in the acceptance group and significantly influenced vaccination intention as revealed by multivariate analyses (Table 1).

Table 1.

Awareness towards COVID-19 and SARS-CoV-2 vaccine associated with vaccination intention

Awareness towards COVID-19 and SARS-CoV-2 vaccineAcceptance(N=60)Hesitancy(N=41)UnivariateAnalysis§Multivariate Analysis||Median[IQR]Median[IQR]p-valuep-valueExpectation of susceptibility to severe COVID-19*2.0[1.0-3.0]2.0[1.5-2.5]0.84720.3440Expectation of vaccine efficacy†3.0[3.0-3.0]2.0[1.0-3.0]<0.0001¶<0.0001**Concerns about the diminishing effect of the vaccine due to current treatment‡2.0[1.0-3.0]3.0[2.0-3.0]0.04750.3600Concerns about the effect of vaccination on treatment‡3.0[1.0-3.0]3.0[2.0-4.0]0.01280.6232Concern about the effect of vaccination on primary disease status‡3.0[1.0-3.0]3.0[2.0-3.0]0.05760.7134Concern about the effect of vaccination on adverse reaction‡3.0[3.0-3.0]3.0[3.0-4.0]0.00930.8335

*0: Less likely to become severe~3: Very likely to become severe, †0: Not expected at all~4: Highly expected, ‡0: Not concerned at all ~4:Very concerned

§Pearson’s chi-square test or Wilcoxon test, ||Nominal logistic regression analysis, ¶ p<0.008 (after Bonferroni correction), ** p<0.05.

Conclusion

The perception of vaccine efficacy is strongly correlated with vaccine acceptance. In order to promote vaccination in patients with RMDs, this study suggests that emphasizing the efficacy of the vaccine may be more effective than alleviating anxiety about the adverse effects of the vaccine.

References

[1]Strangfeld, A. et al. Ann. Rheum. Dis. 2021; 80: 930–942.

Disclosure of Interests

Haruka Sugawara: None declared, Hiroshi Doi: None declared, Takeshi Iwasaki: None declared, Yoichi Nakayama: None declared, Yuri Nishida: None declared, Yoshie Gon: None declared, Masaki Kamakura: None declared, Kenshi Ohbori: None declared, Naoko Sakane: None declared, Naomi Nakamura: None declared, Takahiko Utsumi: None declared, Akio Morinobu Speakers bureau: Eli Lilly Japan K.K., Ono Pharmaceutical Co., Pfizer Inc., UCB Japan, AbbVie G.K., Asahi Kasei Pharma., and Chugai Pharmaceutical Co. Ltd., Grant/research support from: Eli Lilly Japan K.K., Ono Pharmaceutical Co., Pfizer Inc., UCB Japan, AbbVie G.K., Asahi Kasei Pharma., and Chugai Pharmaceutical Co. Ltd.

Anti-PD1 checkpoint inhibitor therapy in acral melanoma: a multicenter study of 193 Japanese patients

BACKGROUND

Acral melanoma (AM) is an epidemiologically and molecularly distinct entity that is underrepresented in clinical trials on immunotherapy in melanoma. We aimed to analyze the efficacy of anti-programmed cell death 1 (anti-PD-1) antibodies in advanced AM.

PATIENTS AND METHODS

We retrospectively evaluated unresectable stage III or stage IV AM patients treated with an anti-PD-1 antibody in any line at 21 Japanese institutions between 2014 and 2018. The clinicobiologic characteristics, objective response rate (ORR, RECIST), survival estimated using Kaplan-Meier analysis, and toxicity (Common Terminology Criteria for Adverse Events 4.0.) were analyzed to estimate the efficacy of the anti-PD-1 antibodies.

RESULTS

In total, 193 patients (nail apparatus, 70; palm and sole, 123) were included in the study. Anti-PD-1 antibody was used as first-line therapy in 143 patients (74.1%). Baseline lactate dehydrogenase (LDH) was within the normal concentration in 102 patients (52.8%). The ORR of all patients was 16.6% (complete response, 3.1%; partial response, 13.5%), and the median overall survival (OS) was 18.1 months. Normal LDH concentrations showed a significantly stronger association with better OS than abnormal concentrations (median OS 24.9 versus 10.7 months; P < 0.001). Although baseline characteristics were similar between the nail apparatus and the palm and sole groups, ORR was significantly lower in the nail apparatus group [6/70 patients (8.6%) versus 26/123 patients (21.1%); P = 0.026]. Moreover, the median OS in this group was significantly poorer (12.8 versus 22.3 months; P = 0.03).

CONCLUSIONS

Anti-PD-1 antibodies have limited efficacy in AM patients. Notably, patients with nail apparatus melanoma had poorer response and survival, making nail apparatus melanoma a strong candidate for further research on the efficacy of novel combination therapies with immune checkpoint inhibitors.

Intensity-modulated radiation therapy administered to a previously irradiated spine is effective and well-tolerated

PURPOSE

This study sought to discern the clinical outcomes of intensity-modulated radiation therapy (IMRT) administered to the spine in patients who had undergone previous radiotherapy.

METHODS

A total of 81 sites of 74 patients who underwent previous radiotherapy administered to the spine or peri-spine and subsequently received IMRT for the spine were analyzed in this study. The prescribed dose of 80 Gy in a biologically effective dose (BED) of α/β = 10 (BED₁₀) was set as the planning target volume. The constraint for the spinal cord and cauda equine was D_0.1 cc ≤ 100 Gy and ≤ 150 Gy of BED for re-irradiation alone and the total irradiation dose, respectively.

RESULTS

The median follow-up period was 10.1 (0.9-92.1) months after re-irradiation, while the median interval from the last day of the previous radiotherapy to the time of re-irradiation was 15.6 (0.4-210.1) months. Separately, the median prescript dose of re-irradiation was 78.0 (28.0-104.9) of BED₁₀. The median survival time in this study was 13.9 months, with 1-, 3-, and 5-year overall survival rates of 53.7%, 29.3%, and 26.6%, respectively. The 1-, 3-, and 5-year local control rates were 90.8%, 84.0%, and 84.0%, respectively. Neurotoxicity was observed in two of 72 treatments (2.8%) assessed after re-irradiation.

CONCLUSION

Re-irradiation for the spine using IMRT seems well-tolerated. Definitive re-irradiation can be a feasible treatment option in patients with the potential for a good prognosis.

THU0285 ANALYSIS OF THE RELATIONSHIP BETWEEN ORGAN DAMAGE AND QUALITY OF LIFE IN PATIENTS WITH SYSTEMIC LUPUS ERYTHEMATOSUS

Background:

Systemic lupus erythematosus (SLE) is an autoimmune disease that can not only cause systemic symptoms, such as fever and arthritis, but can also damage important organs, such as those of the central nervous system and the kidneys. Prevention of irreversible organ damage is important for better prognosis [1]. Additionally, the importance of maintaining the quality of life (QOL) of patients has recently been emphasized. However, only a few studies have examined the relationship between irreversible organ damage and patient QOL.

Objectives:

To assess the relationship between organ damage and QOL, and to survey which organs have more significant effects on QOL.

Methods:

We conducted a questionnaire-based survey of 183 patients with SLE at Kyoto University Hospital from September to December 2019. We used the SLICC/ACR Damage Index (SDI) to evaluate organ damage [2]. The following five scales were employed to evaluate QOL: the physical (PCS) and mental component summary (MCS) of the Medical Outcome Study (MOS) 36-Item Short-Form Health Survey version 2.0 (SF-36v2) [3], health (HRQOL) and non-health-related QOL (N-HRQOL) of LupusPRO [4], and SLE Symptom Checklist (SSC) [5].

Results:

Linear regression analysis showed significant correlation between the SDI score and all QOL scales except for N-HRQOL, suggesting negative effects of organ damage on QOL (Table 1). Next, we analysed whether there was a significant difference in the SF-36 score between those who were positive and negative for each SDI item (41 in total), using the Wilcoxon rank sum test. Muscle atrophy or weakness (p= 3.0×10-10), osteoporosis with fracture or vertebral collapse (p= 9.7×10-8), claudication (p= 7.4×10-5), and cognitive impairment or major psychosis (p= 9.9×10-5) significantly correlated (p< 1.2×10-3) with PCS, and scarring chronic alopecia (p= 3.4×10-4) with MCS (Table 2). In addition, the five SDI items significantly correlated with the remaining three QOL scales (HRQOL, N-HRQOL, and SSC;p< 0.05).

Table 1.

Relationship between the SDI score and QOL

SF-36LupusPROSSCPCSMCSHRQOLN-HRQOLp-value<2.0×10-161.7×10-32.2×10-110.231.9×10-8Table 2.

Relationship between each SDI item and the SF-36 score (p< 1.2×10-3

SDI itemPCS scorep-valuePositive(Median (IQR))Negative(Median (IQR))Muscle atrophy/weakness33 (19-45)50 (43-54)3.0×10-10Osteoporosis with fracture/vertebral collapse24 (12-32)49 (38-54)9.7×10-8Claudication31 (19-35)49 (38-54)7.4×10-5Cognitive impairment/psychosis27 (17-33)49 (38-54)9.9×10-5SDI itemMCS scorep-valuePositive(Median (IQR))Negative(Median (IQR))Scarring chronic alopecia42 (29-51)49 (39-54)3.4×10-4

Conclusion:

We demonstrated that organ damage has negative effects on patient QOL, indicating the importance of preventing irreversible organ damage for maintaining QOL. Moreover, muscle atrophy/weakness, osteoporosis with fracture/vertebral collapse, claudication, cognitive impairment/major psychosis, and scarring chronic alopecia significantly correlated with QOL deterioration, suggesting that these items should be examined with special care in clinical practice.

References:

[1]Lopez R, et al. Rheumatology (Oxford). 2012; 51:491-498.

[2]Gladman D, et al. Arthritis Rheum. 1996; 39:363-369.

[3]Fukuhara S, et al. J Clin Epidemiol. 1998; 51:1037-1044.

[4]Inoue M, et al. Lupus. 2017; 26:849-856.

[5]Grootscholten C, et al. Qual Life Res. 2003; 12:635–644.

Disclosure of Interests:

Yudai Takase: None declared, Hiroshi Doi: None declared, Takeshi Iwasaki: None declared, Motomu Hashimoto Grant/research support from: Bristol-Myers Squibb, Eisai, and Eli Lilly and Company., Speakers bureau: Bristol-Myers Squibb and Mitsubishi Tanabe Pharma., Ryuta Inaba: None declared, Tomohiro Kozuki: None declared, Masashi Taniguchi: None declared, Yuya Tabuchi Paid instructor for: Astellas Pharma, GlaxoSmithKline, Mitsubishi Tanabe Pharma, and Nippon Shinyaku., Speakers bureau: AbbVie, Janssen Pharmaceutical, Mitsubishi Tanabe Pharma, Nippon Shinyaku, and Novartis Pharma. (Outside the field of the present study.), Koji Kitagori: None declared, Syuji Akizuki: None declared, Kosaku Murakami Speakers bureau: AbbVie, Eisai, and Mitsubishi Tanabe Pharma., Ran Nakashima Grant/research support from: Takeda Pharmaceutical. (Outside the field of the present study.), Speakers bureau: Astellas Pharma, Medical & Biological Laboratories, AstraZeneca, and Boehringer Ingelheim. (Outside the field of the present study.), Hajime Yoshifuji Grant/research support from: Astellas Pharma. (Outside the field of the present study.), Speakers bureau: Chugai Pharmaceutical. (Outside the field of the present study.), Wataru Yamamoto: None declared, Masao Tanaka Grant/research support from: AbbVie, Asahi Kasei Pharma, Astellas Pharma, Ayumi Pharmaceutical, Chugai Pharmaceutical, Eisai, Mitsubishi Tanabe Pharma, Taisho Pharmaceutical, and UCB Japan.

, Speakers bureau: AbbVie, Asahi Kasei Pharma, Astellas Pharma, Bristol-Myers Squibb, Chugai Pharmaceutical, Eisai, Eli Lilly and Company, Janssen Pharmaceutical, Mitsubishi Tanabe Pharma, Novartis Pharma, Pfizer, Taisho Pharmaceutical, Takeda Pharmaceutical, and UCB Japan., Koichiro Ohmura Grant/research support from: Astellas Pharma, AYUMI Pharmaceutical, Chugai Pharmaceutical, Daiichi Sankyo, Eisai, Japan Blood Products Organization, Mitsubishi Tanabe Pharma, Nippon Kayaku, Nippon Shinyaku, Sanofi, and Takeda Pharmaceutical., Speakers bureau: AbbVie, Actelion Pharmaceuticals Japan, Asahi Kasei Pharma, AYUMI Pharmaceutical, Bristol-Myers Squibb, Chugai Pharmaceutical, Eisai, Eli Lilly and Company, GlaxoSmithKline, Janssen Pharmaceutical, Mitsubishi Tanabe Pharma, Novartis Pharma, and Sanofi.

Birth order and paediatric allergic disease: A nationwide longitudinal survey

BACKGROUND

Environmental factors seem to be related to the incidence of allergic disease. Children with a later birth order are often exposed to environments, where pathogens and endotoxins can be found, and thus have a higher risk of developing infectious diseases. Therefore, birth order is regarded as an indicator that reflects post-natal environment. However, longitudinal studies are limited on this subject. This study sought to elucidate the relationships between birth order and allergic disease.

METHODS

From a nationwide longitudinal study that followed children born in 2001 (n = 47 015), we selected doctors' visits for 3 types of allergic disease-bronchial asthma, food allergy and atopic dermatitis-from infancy to 12 years of age and conducted binomial log-linear regression analysis to evaluate the associations between birth order and these diseases. We adjusted for the child and parental factors and estimated risk ratio (RR) and 95% confidence interval (CI) for each outcome.

RESULTS

The associations between birth order and bronchial asthma were diverse; later birth order increased the risk in early childhood, but decreased the risks during school age. For example, the adjusted RR comparing third-born or higher and first-born children was 1.19 (95% CI, 1.05-1.35) between 30 and 42 months of age, but was 0.76 (95% CI, 0.65-0.89) between 10 and 11 years. Later birth order was generally protective for food allergy but increased the risk of atopic dermatitis.

CONCLUSION

The influence of birth order depended on the type of allergic disease and the childhood period. Childhood is unique in terms of physical and immunological development, and the immune response to the post-natal environment in childhood appears to be heterogeneous.

Effects of tongue cleaning on Ayurvedic digestive power and oral health-related quality of life: A randomized cross-over study

OBJECTIVES

The effect of tongue cleaning on digestive power is mentioned in Ayurvedic information sources. However, no study has yet evaluated this. We aimed to evaluate the effects of tongue cleaning on digestive power from Ayurvedic viewpoint, and on oral health-related quality of life (OHRQoL) in healthy adults.

DESIGN

Randomized cross-over.

INTERVENTIONS

We recruited healthy adults aged 20-60 years. After randomization, the immediate intervention group started tongue cleaning with a tongue scraper every morning for 4 weeks, and then waited for 4 weeks. The delayed intervention group initially waited for 4 weeks, and then started tongue cleaning in the same way.

MAIN OUTCOME MEASURES

We assessed the outcomes using the questionnaire on digestive power from Ayurvedic viewpoint, and the General Oral Health Assessment Index for OHRQoL. We estimated the effects of tongue cleaning using generalized estimating equations (GEE). We also conducted a sensitivity analysis, by comparing the changes in outcomes during the first 4 weeks of both groups.

RESULTS

Of 58 participants, 57 completed the study. In GEE analysis, tongue cleaning showed improvement in some components of Ayurvedic digestive power represented by fecal and body conditions. For example, the odds ratio for improvement of constipation was 2.80 (95% CI: 1.04-7.58). The General Oral Health Assessment Index score was significantly increased by 4.33 points (95% CI: 2.18-6.48) after tongue cleaning. In sensitivity analyses, the trends of the results were similar to the main GEE analyses.

CONCLUSIONS

Tongue cleaning may be an effective method to improve digestive power and OHRQoL.

An unusual clinical presentation of lupus erythematosus tumidus localized on the thigh

A 44-year-old woman with seronegative polyarthritis presented with a 2-year history of a solitary, bluish-red, oedematous, nonscaly, annular and partially reticulated macule on her right thigh. Histopathological findings revealed perivascular and periadnexal lymphocytic infiltrate in the dermis. Alcian blue and colloidal iron stains highlighted mucinous deposit in the upper and mid dermis. Direct immunofluorescence showed a linear deposit of IgG and C3 along the basement membrane zone. Antinuclear antibody was positive at a titre of 1 : 80, with homogenous and speckled patterns. Except for its unusual localization and lack of photosensitivity, our case had the clinical and histopathological features of lupus erythematosus tumidus. These characteristics were also reminiscent of reticular erythematous mucinosis and erythema annulare centrifugum, both of which are considered to be associated with cutaneous lupus erythematosus (CLE). Hydroxychloroquine 200 mg daily led to improvement of the skin lesion. The unusual clinical presentation of our case emphasizes the heterogeneity of clinical manifestations of CLE.

Contemporary evolution of host plant range expansion in an introduced herbivorous beetle Ophraella communa

Host range expansion of herbivorous insects is a key event in ecological speciation and insect pest management. However, the mechanistic processes are relatively unknown because it is difficult to observe the ongoing host range expansion in natural population. In this study, we focused on the ongoing host range expansion in introduced populations of the ragweed leaf beetle, Ophraella communa, to estimate the evolutionary process of host plant range expansion of a herbivorous insect. In the native range of North America, O. communa does not utilize Ambrosia trifida, as a host plant, but this plant is extensively utilized in the beetle's introduced range. Larval performance and adult preference experiments demonstrated that native O. communa beetles show better survival on host plant individuals from introduced plant populations than those from native plant populations and they also oviposit on the introduced plant, but not on the native plant. Introduced O. communa beetles showed significantly higher performance on and preference for both introduced and native A. trifida plants, when compared with native O. communa. These results indicate the contemporary evolution of host plant range expansion of introduced O. communa and suggest that the evolutionary change of both the host plant and the herbivorous insect involved in the host range expansion.

Control of parental investment changes plastically over time with residual reproductive value

Evolutionary conflict between parents and offspring over parental resource investment is a significant selective force on the traits of both parents and offspring. Empirical studies have shown that for some species, the amount of parental investment is controlled by the parents, whereas in other species, it is controlled by the offspring. The main difference between these two strategies is the residual reproductive value of the parents or opportunities for future reproduction. Therefore, this could explain the patterns of control of parental investment at the species level. However, the residual reproductive value of the parents will change during their lifetime; therefore, parental influence on the amount of investment can be expected to change plastically. Here, we investigated control of parental investment when parents were young and had a high residual reproductive value, compared to when they were old and had a low residual reproductive value using a cross-fostering experiment in the burying beetle Nicrophorus quadripunctatus. We found that parents exert greater control over parental investment when they are young, but parental control is weakened as the parents age. Our results demonstrate that control of parental investment is not fixed, but changes plastically during the parent's lifetime.

Diurnal and circadian oscillations in expression of kisspeptin, kisspeptin receptor and gonadotrophin-releasing hormone 2 genes in the grass puffer, a semilunar-synchronised spawner

In seasonally breeding animals, the circadian and photoperiodic regulation of neuroendocrine system is important for precisely-timed reproduction. Kisspeptin, encoded by the Kiss1 gene, acts as a principal positive regulator of the reproductive axis by stimulating gonadotrophin-releasing hormone (GnRH) neurone activity in vertebrates. However, the precise mechanisms underlying the cyclic regulation of the kisspeptin neuroendocrine system remain largely unknown. The grass puffer, Takifugu niphobles, exhibits a unique spawning rhythm: spawning occurs 1.5-2 h before high tide on the day of spring tide every 2 weeks, and the spawning rhythm is connected to circadian and lunar-/tide-related clock mechanisms. The grass puffer has only one kisspeptin gene (kiss2), which is expressed in a single neural population in the preoptic area (POA), and has one kisspeptin receptor gene (kiss2r), which is expressed in the POA and the nucleus dorsomedialis thalami. Both kiss2 and kiss2r show diurnal variations in expression levels, with a peak at Zeitgeber time (ZT) 6 (middle of day time) under the light/dark conditions. They also show circadian expression with a peak at circadian time 15 (beginning of subjective night-time) under constant darkness. The synchronous and diurnal oscillations of kiss2 and kiss2r expression suggest that the action of Kiss2 in the diencephalon is highly dependent on time. Moreover, midbrain GnRH2 gene (gnrh2) but not GnRH1 or GnRH3 genes show a unique semidiurnal oscillation with two peaks at ZT6 and ZT18 within a day. The cyclic expression of kiss2, kiss2r and gnrh2 may be important in the control of the precisely-timed diurnal and semilunar spawning rhythm of the grass puffer, possibly through the circadian clock and melatonin, which may transmit the photoperiodic information of daylight and moonlight to the reproductive neuroendocrine centre in the hypothalamus.

Hydrocarbon Deposition Attenuates Osteoblast Activity on Titanium

Although the reported percentage of bone-implant contact is far lower than 100%, the cause of such low levels of bone formation has rarely been investigated. This study tested the negative biological effect of hydrocarbon deposition onto titanium surfaces, which has been reported to be inevitable. Osteogenic MC3T3-E1 cells were cultured on titanium disks on which the carbon concentration was experimentally regulated to achieve carbon/titanium (C/Ti) ratios of 0.3, 0.7, and 1.0. Initial cellular activities such as cell attachment and cell spreading were concentration-dependently suppressed by the amount of carbon on the titanium surface. The osteoblastic functions of alkaline phosphatase activity and calcium mineralization were also reduced by more than 40% on the C/Ti (1.0) surface. These results indicate that osteoblast activity is influenced by the degree of hydrocarbon contamination on titanium implants and suggest that hydrocarbon decomposition before implant placement may increase the biocompatibility of titanium.

A possible mechanism of the nucleus accumbens and ventral pallidum 5-HT1B receptors underlying the antidepressant action of ketamine: a PET study with macaques

Ketamine is a unique anesthetic reagent known to produce various psychotic symptoms. Ketamine has recently been reported to elicit a long-lasting antidepressant effect in patients with major depression. Although recent studies provide insight into the molecular mechanisms of the effects of ketamine, the antidepressant mechanism has not been fully elucidated. To understand the involvement of the brain serotonergic system in the actions of ketamine, we performed a positron emission tomography (PET) study on non-human primates. Four rhesus monkeys underwent PET studies with two serotonin (5-HT)-related PET radioligands, [(11)C]AZ10419369 and [(11)C]DASB, which are highly selective for the 5-HT1B receptor and serotonin transporter (SERT), respectively. Voxel-based analysis using standardized brain images revealed that ketamine administration significantly increased 5-HT1B receptor binding in the nucleus accumbens and ventral pallidum, whereas it significantly reduced SERT binding in these brain regions. Fenfluramine, a 5-HT releaser, significantly decreased 5-HT1B receptor binding, but no additional effect was observed when it was administered with ketamine. Furthermore, pretreatment with 2,3-dihydroxy-6-nitro-7-sulfamoylbenzo(f)quinoxaline (NBQX), a potent antagonist of the glutamate α-amino-3-hydroxy-5-methylisoxazole-4-propionic acid (AMPA) receptor, blocked the action of ketamine on the 5-HT1B receptor but not SERT binding. This indicates the involvement of AMPA receptor activation in ketamine-induced alterations of 5-HT1B receptor binding. Because NBQX is known to block the antidepressant effect of ketamine in rodents, alterations in the serotonergic neurotransmission, particularly upregulation of postsynaptic 5-HT1B receptors in the nucleus accumbens and ventral pallidum may be critically involved in the antidepressant action of ketamine.

Saliva collection by using filter paper for measuring cortisol levels in dogs

Four experiments were conducted to evaluate the accuracy and reliability of noninvasive evaluation of cortisol in saliva of dogs. In experiment 1, we measured the cortisol concentration in the filter paper on which 250-μL cortisol solutions had been quantitatively pipetted and in filter papers dipped in cortisol solution. In experiment 2, we collected the blood and saliva of dogs 3 times at 30-min intervals and compared the cortisol concentrations to examine whether the dynamics of cortisol in the blood and saliva are similar. The results of experiments 1 and 2 showed that the cortisol concentration can be quantitatively measured with this method and that the dynamics of cortisol concentration in the plasma and saliva collected by using filter paper are not different (P = 0.14 for experiment 1 and P = 0.51 for experiment 2). In experiment 3, to investigate the factors related to inducing stress in dogs by using the filter-paper method of collecting saliva, we compared the cortisol concentrations at 0 and 30 min after collecting the saliva of pet dogs. The dog owners completed a survey on their dogs, providing basic information and reporting the collection of their dog's saliva. We found that the cortisol concentrations increased significantly in dogs whose owners spent >2 min collecting saliva (P = 0.005), suggesting that prompt collection of saliva is necessary for accurate assessment of cortisol without induction of a stress response. In addition, the cortisol concentrations increased significantly in dogs whose teeth were not regularly brushed (P = 0.04), suggesting that regular teeth brushing mitigates the effect of the collection process on cortisol concentrations in the saliva, with minimal stress to the dogs. In experiment 4, we measured cortisol concentrations in pet dogs accustomed to having their teeth brushed by their owners, before and after interaction with their owners, to assess whether brushing induces stress in dogs. We detected that the cortisol concentrations significantly decreased after human-dog interaction (P = 0.008), suggesting that this method does not induce stress in dogs. Our study indicates that the method of saliva collection by using filter paper is effective in measuring the cortisol concentrations to evaluate stress, although certain steps are required to enhance accuracy.

Topical treatment with basic fibroblast growth factor promotes wound healing and barrier recovery induced by skin abrasion

It has been reported that basic fibroblast growth factor (bFGF) promotes the healing of skin ulceration by inducing fibroblast proliferation, yet the role of bFGF on epidermal barrier function, especially from the perspective of scratch-induced skin abrasion, remains unknown. To this end, we initially developed an epidermal abrasion mouse model induced by scratching with a stainless-steel wire brush, and examined the effects of bFGF on the wound healing induced by skin abrasion. This procedure induced a significant elevation of transepidermal water loss (TEWL) in a scratch-count-dependent manner. This elevated TEWL was significantly decreased following topical application of bFGF to the skin. In addition, bFGF increased the expression of Ki67 in keratinocytes following mechanical scratching. These results suggest that bFGF enhances keratinocyte proliferation, which, in turn, repairs the skin barrier disruption and wounds caused by scratching in mice. Consistently, bFGF stimulated proliferation of normal human epidermal keratinocytes (NHEK). Intriguingly, the effect of bFGF and other growth factors on NHEK proliferation was additive. However, high cell density diminished the effect of bFGF on NHEK proliferation. This particular result can be explained by our observation that FGF receptor mRNA expression in NHEK was low under conditions of high cell density. Our findings suggest that bFGF stimulates keratinocyte proliferation, especially in a lower cell density environment, to repair skin wound in accord with skin barrier recovery.

Effects of interferon-α-transduced tumor cell vaccines and blockade of programmed cell death-1 on the growth of established tumors

Interferon-alpha (IFN-α) has strong antitumor effects, and IFN-α gene therapy has been used clinically against some cancers. In this study, we evaluated the efficacy of the combination of IFN-α-transduced tumor cell vaccines and programmed cell death 1 (PD-1) blockade, and investigated the mechanisms of the antitumor effects of the combined therapy. A poorly immunogenic murine colorectal cancer cell line, MC38, was transduced to overexpress IFN-α. In a therapeutic model, parental tumor-bearing mice were inoculated with MC38-IFNα cells and an anti-PD-1 antagonistic antibody. Analyses of immunohistochemistry and tumor-specific lysis were performed. The outgrowth of the established tumors was significantly reduced in mice treated with the combination of IFN-α and anti-PD-1. Immunohistochemical analyses of the therapeutic model showed marked infiltration of CD4(+) cells and CD8(+) cells in the established MC38 tumors of mice treated with both IFN-α and anti-PD-1. Significant tumor-specific cytolysis was detected when splenocytes of mice that were treated with both IFN-α and anti-PD-1 were used as effector cells. These results suggest that blockade of the PD-1 PD-ligand enhanced the Th1-type antitumor immune responses induced by IFN-α. The combination of IFN-α gene-transduced tumor cell vaccines and PD-1 blockade may be a possible candidate for a cancer vaccine for clinical trials.