Relationship between exercise habits and physical function in children aged 9-12 years.

Exercise improves physical health and positively impacts physical functions in children. Additionally, the habitual exercise established during childhood often continues into adulthood. Therefore, childhood is an important period for establishing healthy habits. Investigating the relationship between the presence or absence of daily exercise and physical functions may provide important information to confirm poor physical function in children with poor exercise habits. Therefore, this study examined the relationship between exercise habits as defined by the Japanese Ministry of Health, Labor, and Welfare and physical function in children aged 9-12 years. Approximately 239 children were included in this study. Participants answered a questionnaire about their exercise habits. We evaluated the skeletal muscle mass index, grip strength, standing broad jump, one-leg standing time, and gait deviation index. Logistic regression analyses were performed to assess exercise habit association with skeletal muscle mass index, physical function, and gait deviation index after adjusting for sex. Of the 239 children, 75.5% (n = 178) had exercise habits. A significant association was noted between exercise habits and skeletal muscle mass index and standing broad jump (skeletal muscle mass index: OR, 1.84; 95% CI, 1.01-3.36 and p<0.05; standing long jump: OR, 1.02; 95% CI, 1.00-1.04 and p<0.05). In conclusion, exercise regardless of exercise level for at least 30 min per day, 2 days per week, for at least 1 year is important for skeletal muscle mass and instantaneous lower limb muscular strength development in school-aged children.

Relationship between low-back pain and flexibility in children: A cross-sectional study.

Low-back pain is common among school-aged children. Decreased trunk flexibility in childhood influences low-back pain in adulthood. Previous studies examining the association between low-back pain and trunk flexibility in children are insufficient. Examining this association among elementary school children may help to better understand trunk flexibility in children with low-back pain and to modify the management of inflexibility. Therefore, this study aimed to identify the prevalence of low-back pain and its relationship with physical function among elementary school students. School-aged children aged 6-12 years were recruited in Japan between May 2018 and March 2023. Fingertip-to-floor distance, back muscle strength, pelvic tilt angle during gait, and the visual analog scale for low-back pain were measured. In addition, factors independently related to low-back pain were determined through logistic regression analysis. Low-back pain was reported in 9.6% of the 394 participants (boys, 191; girls, 203). All children with low-back pain presented with back pain when they moved; however, the pain was non-specific. Logistic regression analysis showed that the fingertip-to-floor distance was an independent risk factor for low-back pain (odds ratio, 0.921; p = 0.007). The odds ratios calculated in the logistic regression analysis confirmed that low-back pain frequency increased as the fingertip-to-floor distance decreased. The risk of low-back pain was associated with inflexibility, regardless of sex and muscle strength. These findings suggest that children with low-back pain must increase their trunk and lower extremity flexibility.

Second-Generation AUTACs for Targeted Autophagic Degradation.

Targeted protein degradation via the ubiquitin-proteasome system has emerged as one of the most promising drug discovery modalities. Autophagy, another intracellular degradation system, can target a wide range of nonproteinous substrates as well as proteins, but its application to targeted degradation is still in its infancy. Our previous work revealed a relationship between guanine modification of cysteine residues on intracellular proteins and selective autophagy, resulting in the first autophagy-based degraders, autophagy-targeted chimeras (AUTACs). Based on the research background, all the reported AUTACs compounds contain cysteine as a substructure. Here, we examine the importance of this substructure by conducting SAR studies and report significant improvements in the degrader's activity by replacing cysteine with other moieties. Several derivatives showed sub-µM range degrading activity, demonstrating the increased practical value of AUTACs.

Proton radiotherapy as a treatment strategy to increase survival in locally advanced pancreatic cancer in the body and tail: a retrospective study.

BACKGROUND: Long-term outcomes and prognostic factors of proton radiotherapy for locally advanced pancreatic cancer (LAPC) in the body and tail are still unknown. The aim of this study was to determine the prognostic factors after proton radiotherapy in a large group of patients with LAPC in the body and tail. METHODS: The medical records of 200 patients with LAPC in the body and tail who underwent proton radiotherapy between February 2009 and January 2021 at the Hyogo Ion Beam Medical Center were retrospectively reviewed to identify prognostic factors that contribute to long-term survival. RESULTS: The overall survival rate at 1- and 2-year after PT was 69.6% and 35.4% with a median overall survival of 18.4 months. The 1- and 2-year local progression-free, and progression-free survival rates were 84.3% and 68.0%, and 44.3% and 19.4%, respectively. In multivariate analysis, superior mesenteric artery (SMA) invasion (SMA only invasion vs. celiac artery only invasion; P = 0.049: SMA and celiac artery invasion vs. celiac artery only invasion; P = 0.017), carbohydrate antigen 19-9 (CA 19-9) level ≥ 231.9 U/mL (P = 0.001), anterior peripancreatic invasion (P = 0.006), and incomplete scheduled concurrent chemotherapy (P = 0.009) were statistically significant prognostic factors for overall survival. There was no significant difference in local progression-free survival; however, distant metastasis-free survival was statistically worse in patients with prognostic factors than in those without. CONCLUSIONS: Proton radiotherapy for LAPC in the body and tail may be a valuable multidisciplinary treatment option. Patients with SMA invasion, higher pre-proton radiotherapy serum CA 19-9 level, anterior peripancreatic invasion, or incomplete scheduled concurrent chemotherapy had worse overall survival because of worse distant metastasis-free survival, suggesting that distant metastases have a significant impact on overall survival in such patients. TRIAL REGISTRATION: Retrospectively registered.

C. elegans ATG-5 mutants associated with ataxia.

Intercellular cleaning via autophagy is crucial for maintaining cellular homeostasis, and impaired autophagy has been associated with the accumulation of protein aggregates that can contribute to neurological diseases. Specifically, the loss-of-function mutation in the human autophagy-related gene 5 (ATG5) at E122D has been linked to the pathogenesis of spinocerebellar ataxia in humans. In this study, we generated two homozygous C. elegans strains with mutations (E121D and E121A) at positions corresponding to the human ATG5 ataxia mutation to investigate the effects of ATG5 mutations on autophagy and motility. Our results showed that both mutants exhibited a reduction in autophagy activity and impaired motility, suggesting that the conserved mechanism of autophagy-mediated regulation of motility extends from C. elegans to humans.

Decreased walking efficiency in elementary school children with developmental coordination disorder trait.

OBJECTIVE: To compare walking efficiency, and associated physical function, between children, with and without developmental coordination disorder trait. DESIGN: Cross-sectional study. SETTING: The study was conducted in a Medical and Rehabilitation Center for Developmental Disabilities in Okazaki, Japan. SUBJECTS: The study included 286 children, 6-12 years of age, with and without developmental coordination disorder trait. Developmental coordination disorder trait was defined by a score below the -1 standard deviation on the Japanese version of the Developmental Coordination Disorder Questionnaire. Based on this criterion, 45 children (28 boys) were classified into the developmental coordination disorder trait group and the other 241 (115 boys) in the control group. MEASURES: The following physical function outcomes were measured: single leg stance test; step length variability; and walking efficiency, measured using the 2-min walk test. Logistic regression analysis was used to determine the association between developmental coordination disorder trait and lower walking efficiency and physical function. RESULTS: Compared to the control group, the developmental coordination disorder group showed lower walking efficiency (P = 0.026), higher step length variability (P = 0.047), and shorter single leg stance test (P = 0.001). Developmental coordination disorder was independently associated with walking efficiency (odds ratio, 1.03; 95% confidence interval [CI], 1.001-1.061; P = 0.041) and single leg stance test (odds ratio, 0.99; 95% CI, 0.978-0.996; P = 0.006), but not to step length variability, age, and sex. CONCLUSIONS: Lower walking efficiency increases energy expenditure in children with developmental coordination disorder trait. Interventions to improve walking efficiency could improve the physical function and participation of these children.

Physical Functions among Children before and during the COVID-19 Pandemic: A Prospective Longitudinal Observational Study (Stage 1).

One major impact of the COVID-19 pandemic on children's lifestyles is the lack of exercise owing to activity restrictions. However, information regarding the way in which physical functions among children decline under these circumstances remains scarce. In this study, we compared the physical functions and life habits among children before and during the COVID-19 pandemic in Japan. The participants involved 40 children aged between 9-15 years (23 girls and 17 boys) who were examined medically both before and during the pandemic. The compared variables included muscle strength, static and dynamic balance functions, gait speed, body fat percentage, screen and sleep times, quality of life, and physical activity time. During the pandemic, compared to before the pandemic, children had lower levels of dynamic balance functions (p = 0.039), increased body fat percentages (p < 0.0001), longer screen time per day (p = 0.002), and shorter sleep time per day (p < 0.0001). Between the two periods, there were no significant differences in muscle strength, static balance functions, gait speed, quality of life, and physical activity time. The activity restrictions imposed as a result of the COVID-19 pandemic negatively affect dynamic balance functions, body-fat levels, and life habits among children.

Multicenter study of re-irradiation using carbon-ions for head and neck malignancies after photon radiotherapy.

PURPOSE: The goal of this multicenter retrospective study of patients with head and neck malignancies was to evaluate the efficacy and safety of carbon-ion (C-ion) radiotherapy (RT) after photon RT. METHODS: We enrolled 56 patients with head and neck malignancies who underwent re-irradiation (re-RT) using C-ions between November 2003 and March 2019, treated previously with photon RT. The tumors at re-RT were located in the sinonasal cavities (n = 20, 35.7%), skull base (n = 12, 21.4%), and orbit (n = 7, 12.5%). The tumors at the initial RT were located in the sinonasal cavities (n = 13, 23.2%), skull base (n = 9, 16.1%), and orbit (n = 9, 16.1%). The median period between the initial RT and re-RT was 41 (4-568) months. The most common histology of re-RT was squamous cell carcinoma (n = 11, 19.6%). The most commonly used protocol was 57.6 Gy (relative biological effectiveness) in 16 fractions (n = 23, 41.1%). Surgery preceded re-RT in three patients (5.4%). One patient with malignant melanoma received concurrent chemotherapy. RESULTS: The 2-year local control, progression-free survival, and overall survival rates were 66.5%, 36.9%, and 67.9%, respectively. The median follow-up time was 28 months. Two patients (3.6%) developed grade ≥ 3 acute toxicities, and 14 (25.0%) developed grade ≥ 3 late toxicities. A single patient had confirmed grade 5 dermatitis with infection. CONCLUSION: Re-RT using C-ions for head and neck malignancies after photon RT is an effective treatment with tolerable toxicity.

Physical Activity Related to Body Muscle Mass Index and Stiffness Index in 7-to-10-Year-Old Girls.

The relationship between moderate-to-vigorous physical activity (MVPA) performance time and body muscle mass and stiffness index in pre-puberty school-aged girls has not been fully elucidated. The effect of sexual maturity on bone mass is more pronounced in girls. This study aimed to clarify the relationship between MVPA performance time and the above-mentioned factors. This was a prospective, population-based cohort study of 111 girls aged 7-10 years. Data were collected via medical examination, clinical measurements, and questionnaires. Spearman's ρ analysis was used to determine the association between skeletal muscle mass index (SMI) and stiffness index, muscle strength, and MVPA performance time. Participants who met the recommended MVPA level accounted for only 24.3% (n = 27) of all participating girls (n = 111). The following factors were significantly positively correlated with MVPA level at spearman's ρ analysis: SMI (r = 0.303, p = 0.001), stiffness index (r = 0.229, p = 0.015), grip strength (r = 0.283, p = 0.003), back muscle strength (r = 0.197, p = 0.038), and standing long jump distance (r = 0.288, p = 0.002). Multiple regression analysis's results revealed that SMI (ß = 0.237; p = 0.024) was associated with MVPA performance time. These results can help school-aged girls to pay adequate attention to having healthy physical activity habits to prevent the decline of skeletal muscle mass, stiffness index, and body muscle strength.

Factors associated with long-term survival in gemcitabine-concurrent proton radiotherapy for non-metastatic locally advanced pancreatic cancer: a single-center retrospective study.

BACKGROUND: Factors associated with long-term survival in gemcitabine-concurrent proton radiotherapy (GPT) for non-metastatic, locally advanced pancreatic cancer (LAPC) remain unclear. This study aimed to determine the factors associated with long-term survival in GPT for non-metastatic LAPC. METHODS: The medical records of 123 patients with LAPC treated with GPT between February 2009 and December 2019 at Hyogo Ion Beam Medical Center were retrospectively reviewed to assess the factors associated with long-term survival outcomes. RESULTS: The median overall survival of the total cohort treated with GPT was 18.7 months. The 1- and 2-year overall, local progression-free, and progression-free survival rates were 70.4% and 35.7%, 78.2% and 59.0%, and 38.6% and 20.8%, respectively. Multivariate analysis revealed that LAPCs at the pancreatic body-tail and those without anterior peripancreatic invasion were independently associated with longer overall survival (P = 0.040 and P = 0.015, respectively). The median overall survival of patients with LAPC at the pancreatic body-tail and those with LAPC without anterior peripancreatic invasion were 24.1 and 28.1 months, respectively. LAPCs at the pancreatic body-tail had a higher volume ratio irradiated over 60 Gy equivalents at gross tumor volume than those at the pancreatic head (P < 0.001). LAPCs with anterior peripancreatic invasion had more peritoneal recurrence within 6 months after GTP than those without anterior peripancreatic invasion (P = 0.039). CONCLUSIONS: GPT is a promising treatment option for patients with LAPC at the pancreatic body-tail and those with LAPC without anterior peripancreatic invasion.

Decreased Balance Function in School-Aged Children with Behavioral Problems.

Children with behavioral problems have a high risk of impaired motor performance. However, the characteristics of balance functions and their associations with behavioral traits are unclear in this population. This study aimed to evaluate balance functions and their relationships with the degree of behavioral problems in school-aged children. A total of 209 children, aged 6-10 years, were divided into two groups, those with and those without behavioral problems, using the Strengths and Difficulties Questionnaire (SDQ). Physical assessments included the one-leg standing test (OLST), the two-step test, and the five-times-sit-to-stand test. We compared the data between groups and assessed for correlations in terms of total difficulties and the SDQ subscale scores. Children with behavioral problems showed significantly reduced the OLST results (p < 0.001) and the two-step test results (p = 0.008). The five-times-sit-to-stand test results did not show significant differences between groups. The OLST results were significantly correlated with emotional symptoms (r = -0.22, p < 0.001), hyperactivity/inattention (r = -0.29, p < 0.001), peer relationship problems (r = -0.22, p < 0.001), and total difficulties (r = -0.32, p < 0.001). Meanwhile, the two-step test results showed no significant correlation with the SDQ scores. Children with behavioral problems have poor balance function, thereby increasing the risk for instability. This suggests that the balance function of children with behavioral problems needs to be considered.

Factors Related to Locomotive Syndrome in School-Aged Children in Okazaki: A Cross-Sectional Study.

The relationship of locomotive syndrome with other physical characteristics and lifestyle habits in children has not been fully elucidated. The aim of this study was to assess the prevalence of children's locomotive syndrome, and to determine its relationship with the above-mentioned factors. This was a cross-sectional study of 285 elementary school children who volunteered to participate in a medical checkup for physical function. Data was collected via medical examination, clinical measurements, and questionnaires. A multivariable logistic regression model was used to determine the relationship (odds ratios; ORs) of participants' characteristics, physical functions, and other outcomes determined by questionnaire on locomotive syndrome. The following factors were related to locomotive syndrome: older age (OR = 1.421, 95% confidence interval [CI] [1.039, 1.945]), male sex (OR = 4.011, 95% CI [2.189, 7.347]), and more time spent watching television per day (OR = 1.281, 95% CI [1.001, 1.640]). These results may assist in the encouragement of children to perform appropriate physical activities and avoid unhealthy lifestyle habits, reducing the occurrence of locomotive syndrome.

Predicted probabilities of brain injury after carbon ion radiotherapy for head and neck and skull base tumors in long-term survivors.

BACKGROUND AND PURPOSE: We aimed to determine the risk factors for radiation-induced brain injury (RIBI1) after carbon ion radiotherapy (CIRT) to predict their probabilities in long-term survivors. MATERIALS AND METHODS: We evaluated 104 patients with head, neck, and skull base tumors who underwent CIRT in a regimen of 32 fractions and were followed up for at least 24 months. RIBI was assessed using the Common Terminology Criteria for Adverse Events. RESULTS: The median follow-up period was 45.5 months; 19 (18.3 %) patients developed grade ≥2 RIBI. The maximal absolute dose covering 5 mL of the brain (D5ml) was the only significant risk factor for grade ≥2 RIBI in the multivariate logistic regression analysis (p = 0.001). The tolerance doses of D5ml for the 5% and 50% probabilities of developing grade ≥2 RIBI were estimated to be 55.4 Gy (relative biological effectiveness [RBE]) and 68.4 Gy (RBE) by a logistic model, respectively. CONCLUSION: D5ml was most significantly associated with grade ≥2 RIBI and may enable the prediction of its probability.

Synthesis and Properties of Aromatic-Terminated Diacetylene Organogelators and Their Application to Photopatterning of Polydiacetylenes.

A series of simply structured diacetylene-diamide-based gelators (DAGs) with aromatic terminals were synthesized, and their gelation and subsequent photopolymerization abilities were analyzed. DAGs with an adequate spacer length (n) and tolyl terminals (DA-Tn) interacted with aromatic solvents, such as benzene and xylenes, at elevated temperatures. During the subsequent cooling process, the DAGs interacted with each other through CH-π interactions at their terminal positions. They also formed one-dimensional hydrogen bonding arrays through secondary amides, leading to stable organogels. These gels polymerized into π-conjugated polydiacetylenes (PDAs) under ultraviolet irradiation. In the p-xylene gels of DA-Tn, the spacer length exerted characteristic odd-even effects on the photopolymerization rates over a certain range (n = 3-6), which can be explained by periodic changes in the uniformity of the molecular packing modes. When the gelling solvent was changed to cyclohexane, the gelation and photopolymerization abilities were greatly improved because the DA-Tn gel networks became highly crystallized and transparent to ultraviolet light (254 nm). The ultimate conversion to PDA from DA-T8/cyclohexane gels was 45.2 wt %. Applying photolithographic techniques to the DAG with excellent photopolymerizability in the film state, we successfully fabricated microscale photopatterns of PDA. We also established a convenient removal process (development process) of DA monomers in unexposed areas. The resulting PDA patterns were quite stable to ambient light stimuli.

Selective autophagy as the basis of autophagy-based degraders.

Degrader technologies, which enable the chemical knockdown of disease-causing proteins, are promising for drug discovery. After two decades of research, degraders using the ubiquitin-proteasome system (UPS) are currently in clinical trials. However, the UPS substrates are mainly limited to soluble proteins. Autophagy-targeting chimeras and autophagosome-tethering compounds are degraders that use autophagy, which has functions complementary to the UPS. They can degrade organelles and aggregate-prone proteins, making them promising treatments against age-related conditions such as mitochondrial dysfunction and neurodegenerative diseases. The molecular mechanism of selective autophagy is an ongoing research topic, which explains why autophagy-based degraders were not available until recently. In this review, we introduce four classifications of selective autophagy mechanisms to facilitate the understanding of the degrader design.

Phylogeographic analysis of Saxifraga fortunei complex (Saxifragaceae) reveals multiple origins of morphological and ecological variations in the Japanese Archipelago.

Phenotypic polymorphism within a species is a notable phenomenon in evolutionary biology to understand the process of adaptive speciation and other historical events. The Saxifraga fortunei complex is a widespread herb found in East Asia. It includes several ecotypic taxa corresponding to their habitat environments. The distribution of the various ecotypes in a limited area of the Japanese Archipelago makes the species a suitable model to investigate the impact of population demographic history and natural selection on lineage diversification. Here, Sanger-based sequencing was used to estimate the divergence timeframe between populations of the Eurasian continent and Japan. Genome-wide SNPs obtained by ddRAD sequencing were used to investigate the phylogeographic origins of ecotypic taxa. The phylogenetic analyses revealed the divergence of the Japanese population from the continental population in the late Miocene. Two distinct regional clades of North and South Japan were identified; phenotypic diversification was evident only in the southern clade. The South Japan clades displayed a historical distribution expansion from north to south. The phenotypic variations appeared to have generated during the expansion. The ecotypic boundaries were incongruent with the genetic grouping. We propose that morphological and ecological specialization in Japanese populations was repeatedly generated by local natural selection.

Effects of exercise in patients with connective tissue disease receiving high-dose glucocorticoids: A pilot prospective cohort study.

PURPOSE: High doses of glucocorticoids induce skeletal muscle weakness. The aim of this study was to evaluate the effects of exercise therapy on skeletal muscle strength, mass, and exercise capacity in patients with connective tissue disease treated with high doses of glucocorticoids. METHODS: This prospective, observational, single-center, cohort study included 35 patients aged ≥ 15 years diagnosed with connective tissue disease who received high-dose glucocorticoids and physical training. Exercise therapy, including moderate aerobic and strength training, was performed five times a week. Knee extension strength, skeletal muscle mass, anaerobic threshold, and peak oxygen consumption were measured at the beginning of exercise therapy and at discharge. RESULTS: After 6 weeks of aerobic and strength exercises, skeletal muscle mass significantly decreased by 5.5%, right knee extension decreased by 11.6%, and left knee extension decreased by 9.7%. The anaerobic threshold and peak oxygen consumption significantly increased by 13.0% and 9.0%, respectively. The increase in glucocorticoid dose was inversely correlated with changes in knee extension strength. CONCLUSION: In patients with connective tissue disease being treated with high-dose glucocorticoids, exercise therapy might attenuate the decrease in skeletal muscle mass and strength and increase the anaerobic threshold and peak oxygen consumption, thus moderating the side effects of high-dose glucocorticoid treatment. Trial registration The trial is registered with UMIN (University Hospital Medical Information Network), ID number UMIN000038836.

Inferring historical survivals of climate relicts: the effects of climate changes, geography, and population-specific factors on herbaceous hydrangeas.

Climate relicts hold considerable importance because they have resulted from numerous historical changes. However, there are major interspecific variations among the ways by which they survived climate changes. Therefore, investigating the factors and timing that affected population demographics can expand our understanding of how climate relicts responded to historical environmental changes. Here, we examined herbaceous hydrangeas of genus Deinanthe in East Asia, which show limited distributions and a remarkable disjunction between Japan and central China. Chloroplast genome and restriction site-associated DNA sequencing revealed that speciation event occurred in the late Miocene (ca. 7-9 Mya) in response to global climate change. Two lineages apparently remained not branched until the middle Quaternary, and afterwards started to diverge to regional population groups. The narrow endemic species in central China showed lower genetic diversity (He = 0.082), as its population size rapidly decreased during the Holocene due to isolation in montane refugia. Insular populations in the three Japanese islands (He = 0.137-0.160) showed a genetic structure that was inconsistent with sea barriers, indicating that it was shaped in the glacial period when its range retreated to coastal refugia on the exposed sea floor. Demographic modelling by stairway-plot analysis reconstructed variable responses of Japanese populations: some experienced glacial bottlenecks in refugial isolation, while post-glacial range expansion seemingly exerted founder effects on other populations. Overall, this study demonstrated the involvement of not just one, but multiple factors, such as the interplay between climate changes, geography, and other population-specific factors, that determine the demographics of climate relicts.

Surgical spacer placement for proton radiotherapy in locally advanced pancreatic body and tail cancers: initial clinical results.

BACKGROUND: Particle radiotherapy has increasingly gained acceptance for locally advanced pancreatic cancers owing to superior tumor conformity and dosimetry compared to conventional photon radiotherapy. However, the close proximity of the pancreas to the stomach and duodenum leads to radiation-induced gastrointestinal toxicities, which hinder the delivery of curative doses to the tumor. To overcome this problem, a surgical spacer was placed between the tumor and gastrointestinal tract, and subsequent proton radiotherapy was performed in this study. METHODS: Data from 9 patients who underwent surgical spacer placement and subsequent proton radiotherapy were analyzed. The safety and feasibility of the spacer placement surgery were evaluated; the impact of the spacer on dosimetry was also assessed using dose volume histogram (DVH) analyses, before and after surgical spacer placement. RESULTS: Surgical spacer placement and subsequent proton radiotherapy were successfully completed in all cases. Surgical spacer placement significantly improved the dose intensity covering 95%, mean, and minimum doses for the gross tumor volume, and the clinical and planning target volume based on the DVH, while respecting the dose constraints of the gastrointestinal tract. Based on the Common Terminology Criteria for Adverse Events, two patients (22.2%) developed gastrointestinal ulcer (Grade 2) at 1 and 35 months, and one patient (11.1%) developed gastric perforation (Grade 4) at 4 months after proton radiotherapy. CONCLUSIONS: Surgical spacer placement in the locally advanced pancreatic body and tail cancers is relatively safe and technically feasible. Comparing radiation plans, surgical spacer placement seems to improve the dose distribution in the locally advanced pancreatic body and tail cancers, which are close to the gastrointestinal tract.