DsRNA sequencing revealed a previously missed terminal sequence of a +ssRNA virus that infects dinoflagellate Heterocapsa circularisquama.

Heterocapsa circularisquama RNA virus (HcRNAV) is the only dinoflagellate-infecting RNA virus cultured. However, only two strains of HcRNAV have been registered with complete genome sequences (strains 34 and 109 for UA and CY types, respectively). To extend the genomic information of HcRNAV, we performed full-genome sequencing of an unsequenced strain of HcRNAV (strain A8) using the fragmented and primer-ligated double-stranded RNA (dsRNA) sequencing (FLDS) method. The complete genome of HcRNAV A8 with 4457 nucleotides (nt) was successfully determined, and sequence alignment of the major capsid protein gene suggested that A8 was a UA-type strain, consistent with its intraspecific host specificity. The complete sequence was found to be 80 nt longer at the 5' terminus than the registered sequences of HcRNAV strains (34 and 109), suggesting that FLDS is more reliable for determining the terminal sequence than conventional methods (5' Rapid Amplification of cDNA End). Our study contributes to a better understanding of dinoflagellate-infecting viruses with limited sequence data.

Newer parameters of the octreotide test in patients with acromegaly.

PURPOSE: Predicting the therapeutic effects of first-generation somatostatin receptor ligands (fg-SRLs) is important when assessing or planning effective treatment strategies in patients with acromegaly. The oft-used maximum growth hormone (GH) suppression rate parameter of the octreotide test has a suboptimal predictive value. Therefore, this study explored newer parameters of the octreotide test for predicting the therapeutic effect of long-acting fg-SRLs. METHODS: In this single-center retrospective study, the octreotide test parameters and the therapeutic effects of fg-SRL at 3 months were investigated in 45 consecutive treatment-naïve patients with acromegaly between April 2008 and March 2023. Additionally, the relationship between the octreotide test parameters and the therapeutic effects of fg-SRLs was investigated. Tumor shrinkage was evaluated based on changes in the longitudinal diameter of the macroadenomas. The area GH suppression rate-time under the curve (AUC) and the time to nadir GH level were calculated and compared with the maximum GH suppression rate. RESULTS: The AUC estimated reductions in serum insulin-like growth factor I, and tumor shrinkage. The time to nadir GH level predicted tumor shrinkage more robustly than the maximum GH suppression rate in patients with macroadenoma. CONCLUSION: The AUC and time to nadir GH level may potentially be newer parameters of the octreotide test for estimating the therapeutic effect of fg-SRLs.

Awareness of children's developmental problems and sharing of concerns with parents by preschool teachers and childcare workers: The Japanese context.

BACKGROUND: This study aims to determine the extent to which preschool teachers and childcare workers are aware of the presence of developmental problems among children and to what extent they share information with parents about their concerns regarding a child's development or diagnosis of neurodevelopmental disorders (NDDs). METHODS: We wrote to all 924 preschools and childcare centres in Japan's Nagano and Yamanashi prefectures to request participants. We then sent survey forms to the preschools and childcare centres that agreed to cooperate for three grades comprising 3-, 4- and 5-year-olds in the school year 2020. We asked the staff member in charge of each child to complete the survey. The survey included questions about the teacher's concerns regarding the possibility of an NDD and whether the matter had been shared with the children's parents. RESULTS: We obtained data for 10 354 children from 206 preschools and childcare centres (response rate = 22.3%). Among these children, 457 (4.4%) had an NDD diagnosis that their parents shared with the teachers. However, the teachers of 1274 children (12.3%) had concerns regarding their development but were not informed by the parents about the diagnosis, if any. These 1274 children included 775 (60.8%) cases where the teachers failed to share their concerns with parents because (1) the teachers could not communicate with parents (n = 119), (2) the teachers were not sure if there was a neurodevelopmental problem (n = 360) and (3) the parents were not aware of the problem (n = 296). CONCLUSIONS: Preschool teachers and childcare workers had concerns about the development of a substantial proportion of children in their charge. However, teachers and childcare workers did not share their concerns regarding many children's developmental problems with their parents. The findings suggest that there are challenges in information-sharing between teachers/childcare workers and parents.

Serum leucine-rich alpha-2 glycoprotein and calprotectin in children with inflammatory bowel disease: A multicenter study in Japan.

BACKGROUND AND AIM: Serum leucine-rich alpha-2 glycoprotein (LRG) and calprotectin have been studied as disease activity markers in adults with inflammatory bowel disease (IBD). We evaluated them in pediatric IBD patients. METHODS: Subjects under 17 years old undergoing care at 11 Japanese pediatric centers were retrospectively assigned to 3 groups representing Crohn's disease (CD), ulcerative colitis (UC), and normal controls (NC) with irritable bowel syndrome or no illness. Serum LRG and calprotectin were measured using commercial enzyme-linked immunosorbent assay kits. RESULTS: We enrolled 173 subjects, including 74 with CD, 77 with UC, and 22 NC. Serum LRG concentrations in active CD (median, 200 µg/mL) were significantly greater than in remission (81 µg/mL; P < 0.001) or NC (69 µg/mL; P < 0.001). Serum calprotectin concentrations in active CD (2941 ng/mL) also were significantly greater than in remission (962 ng/mL; P < 0.05) or NC (872 ng/mL; P < 0.05). Serum LRG concentrations in active UC (134 µg/mL) were significantly greater than in remission (65 µg/mL; P < 0.01) but not significantly greater than in NC (69 µg/mL); serum calprotectin concentrations in active UC (1058 ng/mL) were not significantly different from those in remission (671 ng/mL) or NC (872 ng/mL). In receiver operating characteristic analyses of LRG, calprotectin, C-reactive protein, and erythrocyte sedimentation rate for ability to distinguish active IBD from remission, CD and UC showed areas under receiver operating characteristic curves for LRG (0.77 and 0.70, respectively), exceeding those for calprotectin, C-reactive protein, or erythrocyte sedimentation rate. CONCLUSIONS: In pediatric IBD, serum LRG may better reflect disease activity than serum calprotectin, particularly in CD.

Survey of glucocorticoid dose escalation in patients with adrenal insufficiency during the peri-COVID-19 vaccination period.

There is uncertainty regarding the need for COVID-19 peri-vaccination glucocorticoid coverage in patients with adrenal insufficiency. In this survey conducted in a single tertiary medical institution, 167 consecutive outpatients taking physiological glucocorticoids because of adrenal insufficiency were included. The patients declared if they developed an adrenal crisis after vaccination, and the amount and duration of an increase in their glucocorticoid dosage, if any. None of the patients without preventive glucocorticoid increase suffered an adrenal crisis after COVID-19 vaccination. Only 8.3% (14 cases) and 27.5% (46 cases) of the patients needed to escalate the dose of glucocorticoids when systemic symptoms appeared after the first and second injections, respectively. Glucocorticoids were increased in patients <60 years of age more than in patients ≥60 years of age at the time of both the first (p = 0.026) and second injections (p = 0.005). Sex and the causes of adrenal insufficiency were not associated with the frequency of the patients who needed glucocorticoid dose escalation. In the cases with increased glucocorticoids, the median dosage for escalation was 10 mg (hydrocortisone equivalent). In conclusion, even without prophylactic glucocorticoid administration, adrenal crisis did not occur during the peri-COVID-19 vaccination period. The dose escalation of steroid was more frequent in younger patients following the second vaccination. Careful monitoring of adverse effects and the appropriate management of glucocorticoids when necessary are essential following COVID-19 vaccinations.

Serum Zinc and Selenium in Children with Inflammatory Bowel Disease: A Multicenter Study in Japan.

BACKGROUND: Reports of zinc and selenium deficiencies accompanying inflammatory bowel disease (IBD) mostly have originated from Western countries and concerned adult patients. Whether Japanese children with IBD have similar deficiencies remained unclear. AIM: We aimed to elucidate differences in serum zinc and selenium concentrations in Japanese children between types of IBD. METHODS: Children under 17 years old undergoing care at 12 Japanese pediatric centers were retrospectively enrolled between November 2016 and February 2018 to 3 groups representing Crohn's disease (CD), ulcerative colitis (UC), and normal controls (NC) with irritable bowel syndrome or no illnesses. Serum zinc and selenium were measured by atomic absorption spectrophotometry. Zinc and selenium deficiencies were defined by serum concentrations < 70 µg/dL and < 9.5 µg/dL, respectively. RESULTS: Subjects included 98 patients with CD (median age, 13 years), 118 with UC (11 years), and 43 NC (11 years). Serum zinc and selenium were significantly lower in CD (median, 64 and 12.6 µg/dL respectively) than in UC (69 and 14.6; P < 0.05 and P < 0.001) or NC (77 and 15.7; P < 0.01 and P < 0.001). Zinc deficiency was significantly more prevalent in CD (60.2%) than in NC (37.2%; P < 0.05), but not than in UC (51.7%; P = 0.22). Selenium deficiency was significantly more prevalent in CD (15.3%) than in UC (5.9%; P < 0.05) or NC (0%; P < 0.01). CONCLUSIONS: In Japanese children under 17 years old, serum zinc and selenium were significantly lower in CD than in UC or NC. Zinc and selenium should be monitored, and supplemented when deficient, in children with IBD, especially CD.

Serum pepsinogen cut-off values in Helicobacter pylori-infected children.

BACKGROUND: The aim of this study was to evaluate the standard values for gender- and age-stratified serum pepsinogen (sPG) in Helicobacter pylori (H. pylori) non-infected children and to determine the optimal cut-off values of sPG for predicting H. pylori-infected gastritis in children. METHODS: A prospective study for determination of sPG levels was performed in children with epigastric pain who underwent esophagogastroduodenoscopy over the past 16 years. After excluding subjects diagnosed with inflammatory bowel diseases, eosinophilic gastrointestinal disorders, or immunoglobulin A vasculitis, the diagnosis of H. pylori infection was defined by positive tissue culture or concordant-positive results for histology and the rapid urease test. RESULTS: A total of 405 subjects were diagnosed as being H. pylori-infected (79) or non-infected (326). In the H. pylori non-infected group, there were no significant differences in sPG levels among age groups; males had higher sPG I and sPG II levels than females. In the H. pylori-infected group, sPG I and sPG II levels were significantly higher and the sPG I/II ratio was lower than those in the non-infected group. In receiver operating characteristics analyses in diagnosing H. pylori infection, the areas under the curves for sPG I, sPG II and sPG I/II ratio were 0.896, 0.980, and 0.946, respectively. The optimal cut-off value of sPG II of ≥9.0 ng/mL was considered positive for H. pylori infection (sensitivity: 92.4%, specificity: 93.9%). CONCLUSIONS: The optimal cut-off value of sPG II of ≥9.0 ng/mL may be a good predictor of H. pylori-infected gastritis in children.

A consensus statement on health-care transition for childhood-onset inflammatory bowel disease patients.

Inflammatory bowel disease (IBD) is a chronic relapsing inflammatory disorder of the intestine. The incidence of IBD is increasing worldwide, including Japan, and in approximately 25% of all affected patients it is diagnosed before 18 years of age. For the health maintenance of such patients, planned transition to adult care systems is essential. Previous Japanese surveys have revealed gaps between adult and pediatric gastroenterologists with regard to their knowledge and perception of health-care transition for patients with childhood-onset IBD. In 2021-2022, several Web workshops to discuss issues related to the transitional care of IBD patients were held by the Ministry of Health, Labour and Welfare of Japan as part of their program for research on intractable diseases. Clinicians experienced in IBD treatment for pediatric and adult patients participated. As a result, this panel of adult and pediatric gastroenterologists developed five consensus statements on the issue of "transfer from pediatric to adult care" and nine statements on the issue of "addressing transitional care (transition program)." To address current gaps in health-care transition for childhood-onset IBD patients, a programmed approach to transition, and better partnerships between pediatric and adult gastroenterologists are indicated. It is hoped that this consensus statement will provide a basis for the development of appropriate guidelines for clinical practice.

Absent X-linked inhibitor of apoptosis protein expression in T cell blasts and causal mutations including non-coding deletion.

BACKGROUND: X-linked inhibitor of apoptosis protein (XIAP) deficiency is one of inborn errors of immunity characterized by recurrent hemophagocytic lymphohistiocytosis and refractory inflammatory bowel disease (IBD), mimicking Crohn's disease. The aim of this study is to make an accurate diagnosis of XIAP deficiency based on genetic and XIAP expression studies and to investigate endoscopic findings shared by patients with this disease. METHODS: Four male patients with recurrent hemophagocytic lymphohistiocytosis and long-term refractory IBD were studied for the diagnosis of XIAP deficiency. Endoscopic findings of the four patients were also studied in parallel. RESULTS: These four patients were diagnosed with XIAP deficiency based on the absent XIAP expression in cultured T-cell blasts. Sequence analysis of the responsible gene, XIAP, demonstrated two novel nonsense mutations of p.Gln114X and p.Glu25X, and a previously reported nonsense mutation of p.Arg381X. Although no mutations in the coding region were detected in the fourth patient, further studies demonstrated a novel 2,199 bp deletion encompassing non-coding exon 1, presumably affecting transcription and stability of XIAP mRNA. All of the patients eventually underwent hematopoietic stem cell transplantation, leading to a complete or partial remission of IBD. These four patients shared an endoscopic finding of multiple wide and longitudinal ulcers with straight and non-raised edge in the colon. CONCLUSIONS: X-linked inhibitor of apoptosis protein expression in T-cell blasts could facilitate the diagnosis of this disease, especially with causal mutations in non-coding regions.

Isolation of bacteria able to degrade poly-hydroxybutyrate-co-hydroxyhexanoate, and the inhibitory effects of the degradation products on shrimp pathogen Vibrio penaeicida.

Poly-hydroxybutyrate-co-hydroxyhexanoate (PHBH) is a biodegradable, water-insoluble polymer produced by specific bacteria. The monomers of PHBH are the hydroxyalkanoic acids 3-hydroxybutyrate (3HB) and 3-hydroxyhexanoate (3HH). Previously, we reported that 3HB and 3HH showed marked antibacterial activities against the shrimp pathogenic bacterium Vibrio penaeicida, and that addition of 5% (w/w) PHBH to the standard aquaculture diet significantly increased survival rate in kuruma shrimp (Marsupenaeus japonicus) after challenge by V. penaeicida, which we attributed to the degradation of PHBH to its monomers in the shrimp gut. In the present study, we isolated four strains of bacteria with high PHBH-degrading activity and evaluated their inhibitory effects on V. penaeicida with PHBH: one strain from shrimp gut contents (E1; Pseudoalteromonas shioyasakiensis/P. mariniglutinosa), two strains from coastal surface seawater (F1; P. shioyasakiensis/P. mariniglutinosa, and F5; Alcanivorax dieselolei/A. xenomutans), and one strain that was a contaminant in commercial PHBH powder (Y1; Bacillus pseudofirmus). Strains E1, F1, and Y1 showed strong PHBH-degrading activity within 24 h of inoculation to PHBH-containing agar plates. Although none of the isolates alone had any effect on the growth of V. penaeicida, when cultured with E1 or F1 and PHBH, the growth of V. penaeicida was markedly suppressed. Incubation with E1 and PHBH resulted in a gradual reduction in the concentration of V. penaeicida from 2 days after the start of incubation until the concentration was 1.2% of that in the control (V. penaeicida alone). Incubation with F1 and PHBH resulted in a rapid reduction in the concentration of V. penaeicida from 2 days after the start of incubation until the concentration was only 0.32% of that of the control. Compared with strains E1 and F1, Y1 showed similar PHBH-degrading activity but did not show any suppressive effect on the growth of V. penaeicida until 5 days after the start of incubation. In addition, this suppressive effect was relatively weak compared with that of the other two strains, suggesting that Y1 can quickly degrade PHBH but that it takes several days to produce monomers. Together, these results suggest that addition to the aquaculture diet of PHBH and PHBH-degrading bacteria that rapidly degrade PHBH to its monomers may speed up degradation of PHBH to its monomers in the shrimp gut, and that it would increase resistance to infection mortality by V. penaeicida in kuruma shrimp.

Diagnostic accuracy of serum proteinase 3 antineutrophil cytoplasmic antibodies in children with ulcerative colitis.

BACKGROUND AND AIM: Serologic markers such as myeloperoxidase (MPO) antineutrophil cytoplasmic antibodies (ANCA) (MPO-ANCA) have been used to screen patients for ulcerative colitis (UC). However, MPO-ANCA shows limited accuracy in Asians. Proteinase 3 ANCA (PR3-ANCA) has performed better at UC diagnosis in Japanese adults than MPO-ANCA. The present study aimed to evaluate usefulness of PR3-ANCA for diagnosis of UC in Japanese pediatric practice. METHODS: Patients under 17 years old undergoing assessment at 12 Japanese pediatric centers between November 2016 and February 2018 were prospectively enrolled and divided into groups with UC, Crohn's disease (CD), intestinal disease control (IC), and healthy control (HC). Serum PR3-ANCA and MPO-ANCA were analyzed using chemiluminescence enzyme immunoassay kits. RESULTS: Sera from 367 patients (148 with UC at a median age of 12 years; 120 with CD, 13 years; 56 with IC, 10.5 years; and 43 with HC, 10 years) were examined. Median PR3-ANCA values in UC (1.6 U/mL) were greater than in CD (0.2; P < 0.001), IC (0.15; P < 0.001), and HC (0.1; P < 0.001). In receiver operating characteristic curve analyses, the area under the curve for PR3-ANCA was 0.79, significantly greater than for MPO-ANCA (0.58; P < 0.001). Using a cut-off value of 0.8 U/mL determined from the receiver operating characteristic analyses, PR3-ANCA showed significantly greater sensitivity (64.9%) than MPO-ANCA (cut-off, 0.2 U/mL; sensitivity, 19.6%; P < 0.001) and good specificity (83.6%). CONCLUSIONS: In Japanese children and adolescents, PR3-ANCA performed better as a serologic marker for diagnosis of UC than MPO-ANCA. To our knowledge, this is the first report of such a comparison.

Influence of Nutritional Management and Rehabilitation on Physical Outcome in Japanese Intensive Care Unit Patients: A Multicenter Observational Study.

BACKGROUND: There is lack of evidence regarding nutritional management among intensive care unit (ICU) patients in a population with relatively low body mass index. Therefore, we conducted an observational study to assess the nutritional management in Japanese ICUs. Also, we investigated the impact of nutritional management and rehabilitation on physical outcome. METHODS: The study population comprised 389 consecutive patients who received mechanical ventilation for at least 24 h and those admitted to the ICU for > 72 h in 13 hospitals. The primary outcomes were caloric and protein intake in ICU on days 3 and 7, and at ICU discharge. The secondary outcome was the impact of nutritional management and rehabilitation on physical status at ICU discharge. We defined good physical status as more than end sitting and poor physical status as bed rest and sitting. We divided the participants into 2 groups, namely, the good physical status group (Good group) and poor physical status group (Poor group) for analysis of the secondary outcome. Data were expressed as median (interquartile range). RESULTS: The median amount of caloric intake on days 3 and 7, and at ICU discharge via enteral and parenteral routes were 8.4 (3.1-15.6), 14.9 (7.5-22.0), and 11.2 (2.5-19.1) kcal/kg/day, respectively. The median amount of protein intake on days 3 and 7, and at ICU discharge were 0.2 (0-0.5), 0.4 (0.1-0.8), and 0.3 (0-0.7) g/kg/day, respectively. The amount of caloric intake on day 3 in the Poor group was significantly higher than that of the Good group (10.1 [5.8, 16.2] vs. 5.2 [1.9, 12.4] kcal/kg/day, p < 0.001). The proportion of patients who were received rehabilitation in ICU in the Good group was significantly higher than that of the Poor group (92 vs. 63%, p < 0.001). The multivariate analysis revealed that caloric intake on day 3 and rehabilitation in ICU were considered independent factors that affect physical status (OR 1.19; 95% CI 1.05-1.34; p = 0.005 and OR 0.07; 95% CI 0.01-0.34; p = 0.001). CONCLUSIONS: The caloric and protein intakes in Japanese ICUs were 15 kcal/kg/day and 0.4 g/kg/day, respectively. In addition, critically ill patients might benefit from low caloric intake (less than 10 kcal/kg/day) until day 3 and rehabilitation during ICU stay.

Metal Tolerance Protein 8 Mediates Manganese Homeostasis and Iron Reallocation during Seed Development and Germination.

Metal accumulation in seeds is a prerequisite for germination and establishment of plants but also for micronutrient delivery to humans. To investigate metal transport processes and their interactions in seeds, we focused on METAL TOLERANCE PROTEIN8 (MTP8), a tonoplast transporter of the manganese (Mn) subclade of cation diffusion facilitators, which in Arabidopsis (Arabidopsis thaliana) is expressed in embryos of seeds. The x-ray fluorescence imaging showed that expression of MTP8 was responsible for Mn localization in subepidermal cells on the abaxial side of the cotyledons and in cortical cells of the hypocotyl. Accordingly, under low Mn availability, MTP8 increased seed stores of Mn, required for efficient seed germination. In mutant embryos lacking expression of VACUOLAR IRON TRANSPORTER1 (VIT1), MTP8 built up iron (Fe) hotspots in MTP8-expressing cells types, suggesting that MTP8 transports Fe in addition to Mn. In mtp8 vit1 double mutant seeds, Mn and Fe were distributed in all cell types of the embryo. An Fe transport function of MTP8 was confirmed by its ability to complement Fe hypersensitivity of a yeast mutant defective in vacuolar Fe transport. Imbibing mtp8-1 mutant seeds in the presence of Mn or subjecting seeds to wet-dry cycles showed that MTP8 conferred Mn tolerance. During germination, MTP8 promoted reallocation of Fe from the vasculature. These results indicate that cell type-specific accumulation of Mn and Fe in seeds depends on MTP8 and that this transporter plays an important role in the generation of seed metal stores as well as for metal homeostasis and germination efficiency under challenging environmental conditions.

The iron-chelate transporter OsYSL9 plays a role in iron distribution in developing rice grains.

KEY MESSAGE: Rice OsYSL9 is a novel transporter for Fe(II)-nicotianamine and Fe(III)-deoxymugineic acid that is responsible for internal iron transport, especially from endosperm to embryo in developing seeds. Metal chelators are essential for safe and efficient metal translocation in plants. Graminaceous plants utilize specific ferric iron chelators, mugineic acid family phytosiderophores, to take up sparingly soluble iron from the soil. Yellow Stripe 1-Like (YSL) family transporters are responsible for transport of metal-phytosiderophores and structurally similar metal-nicotianamine complexes. Among the rice YSL family members (OsYSL) whose functions have not yet been clarified, OsYSL9 belongs to an uncharacterized subgroup containing highly conserved homologs in graminaceous species. In the present report, we showed that OsYSL9 localizes mainly to the plasma membrane and transports both iron(II)-nicotianamine and iron(III)-deoxymugineic acid into the cell. Expression of OsYSL9 was induced in the roots but repressed in the nonjuvenile leaves in response to iron deficiency. In iron-deficient roots, OsYSL9 was induced in the vascular cylinder but not in epidermal cells. Although OsYSL9-knockdown plants did not show a growth defect under iron-sufficient conditions, these plants were more sensitive to iron deficiency in the nonjuvenile stage compared with non-transgenic plants. At the grain-filling stage, OsYSL9 expression was strongly and transiently induced in the scutellum of the embryo and in endosperm cells surrounding the embryo. The iron concentration was decreased in embryos of OsYSL9-knockdown plants but was increased in residual parts of brown seeds. These results suggested that OsYSL9 is involved in iron translocation within plant parts and particularly iron translocation from endosperm to embryo in developing seeds.

Fundic gland differentiation of oncocytic/pancreatobiliary subtypes of pancreatic intraductal papillary mucinous neoplasm.

AIMS: Intraductal papillary mucinous neoplasms (IPMNs) differentiate in several histological directions, which are related to their clinical behaviour. Differentiation of IPMNs to the gastric foveolar epithelium/pyloric gland (PG) is well known. However, no study has been conducted regarding fundic gland (FG) differentiation. The aim of this study was to determine the frequency of FG differentiation and its relationship with the clinicopathological features of IPMNs, by studying 48 surgically resected IPMN cases consisting of 17 gastric IPMNs, 15 intestinal IPMNs, 10 pancreatobiliary IPMNs, and six oncocytic IPMNs. METHODS AND RESULTS: Clinicopathological data, including histological tumour grade, immunohistochemical data for mucins (MUCs), pepsinogen I, pepsinogen II, and H,K-ATPase, and GNAS/KRAS status, were analysed. Pepsinogen I and H,K-ATPase were used to assess FG differentiation, and pepsinogen II and MUC6 were used to identify the equivalent cell type of the normal FG. Reverse transcription polymerase chain reaction (RT-PCR) for PGA5/PGC (pepsinogen I and pepsinogen II mRNA, respectively) and quantitative real-time RT-PCR (qRT-PCR) for PGA5 were performed to confirm the immunohistochemistry results. Pepsinogen I expression was detected in 12.5% (6/48) of total IPMNs, of which 66.7% (4/6) of oncocytic IPMNs and 20.0% (2/10) of pancreatobiliary IPMNs were pepsinogen I-positive. No H,K-ATPase-positive cases were detected. Three oncocytic IPMNs with pepsinogen I expression showed similar histology to normal FG. RT-PCR and qRT-PCR confirmed the immunohistochemical results. All IPMNs with FG differentiation were of the oncocytic or pancreatobiliary subtype, were of histologically high grade, and were without GNAS mutation. CONCLUSIONS: The differentiation of IPMNs to gastric FG is related to oncocytic and pancreatobiliary subtypes, and to high grade. This is the first report to describe differentiation of IPMNs to the FG, and to reveal its relationship with the clinicopathological features of IPMNs.

Genetic and clinical characteristics of Japanese patients with sporadic somatotropinoma.

Most of acromegaly is caused by a sporadic somatotropinoma and a couple of novel gene mutations responsible for somatotropinoma have recently been reported. To determine the cause of sporadic somatotropinoma in Japanese patients, we analyzed 61 consecutive Japanese patients with somatotropinoma without apparent family history. Comprehensive genetic analysis revealed that 31 patients harbored guanine nucleotide-binding protein, alpha stimulating (GNAS) mutations (50.8%) and three patients harbored aryl hydrocarbon receptor interacting protein (AIP) mutations (4.9%). No patients had G protein-coupled receptor 101 (GPR101) mutations. The patients in this cohort study were categorized into three groups of AIP, GNAS, and others and compared the clinical characteristics. The AIP group exhibited significantly younger age at diagnosis, larger tumor, and higher nadir GH during oral glucose tolerance test. In all patients with AIP mutation, macro- and invasive tumor was detected and repetitive surgery or postoperative medical therapy was needed. One case showed a refractory response to postoperative somatostatin analogue (SSA) but after the addition of cabergoline as combined therapy, serum IGF-I levels were controlled. The other case showed a modest response to SSA and the switching to cabergoline monotherapy was also effective. These data suggest that although resistance to SSA has been reported in patients with AIP mutations, the response to dopamine agonist (DA) may be retained. In conclusion, the cause of sporadic somatotropinoma in Japanese patients was comparable with the previous reports in Caucasians, patients with AIP mutations showed unique clinical characteristics, and DA may be a therapeutic option for patients with AIP mutations.

SIRT1 regulates adaptive response of the growth hormone--insulin-like growth factor-I axis under fasting conditions in liver.

Adaptation under fasting conditions is critical for survival in animals. Sirtuin 1 (SIRT1), a protein deacetylase, plays an essential role in adaptive metabolic and endocrine responses under fasting conditions by modifying the acetylation status of various proteins. Fasting induces growth hormone (GH) resistance in the liver, leading to decreased serum insulin-like growth factor-I (IGF-I) levels as an endocrine adaptation for malnutrition; however, the underlying mechanisms of this action remain to be fully elucidated. Here we report that in vivo knockdown of SIRT1 in the liver restored the fasting-induced decrease in serum IGF-I levels and enhanced the GH-dependent increase in IGF-I levels, indicating that SIRT1 negatively regulates GH-dependent IGF-I production in the liver. In vitro analysis using hepatocytes demonstrated that SIRT1 suppresses GH-dependent IGF-I expression, accompanied by decreased tyrosine phosphorylation on signal transducer and activator of transcription (STAT) 5. GST pull-down assays revealed that SIRT1 interacts directly with STAT5. When the lysine residues adjacent to the SH2 domain of STAT5 were mutated, STAT5 acetylation decreased concomitant with a decrease in its transcriptional activity. Knockdown of SIRT1 enhanced the acetylation and GH-induced tyrosine phosphorylation of STAT5, as well as the GH-induced interaction of the GH receptor with STAT5. These data indicate that SIRT1 negatively regulates GH-induced STAT5 phosphorylation and IGF-I production via deacetylation of STAT5 in the liver. In addition, our findings explain the underlying mechanisms of GH resistance under fasting conditions, which is a known element of endocrine adaptation during fasting.

Nicotianamine synthase 2 localizes to the vesicles of iron-deficient rice roots, and its mutation in the YXXφ or LL motif causes the disruption of vesicle formation or movement in rice.

Graminaceous plants release mugineic acid family phytosiderophores (MAs) to acquire iron from the soil. Here, we show that deoxymugineic acid (DMA) secretion from rice roots fluctuates throughout the day, and that vesicles accumulate in roots before MAs secretion. We developed transgenic rice plants that express rice nicotianamine (NA) synthase (NAS) 2 (OsNAS2) fused to synthetic green fluorescent protein (sGFP) under the control of its own promoter. In root cells, OsNAS2-sGFP fluorescence was observed in a dot-like pattern, moving dynamically within the cell. This suggests that these vesicles are involved in NA and DMA biosynthesis. A tyrosine motif and a di-leucine motif, which have been reported to be involved in cellular transport, are conserved in all identified NAS proteins in plants. OsNAS2 mutated in the tyrosine motif showed NAS activity and was localized to the vesicles; however, these vesicles stuck together and did not move. On the other hand, OsNAS2 mutated in the di-leucine motif lost NAS activity and did not localize to these vesicles. The amounts of NA and DMA produced and the amount of DMA secreted by OsNAS2-sGFP plants were significantly higher than in non-transformants and domain-mutated lines, suggesting that OsNAS2-sGFP, but not the mutated forms, was functional in vivo. Overall, the localization of NAS to vesicles and the transport of these vesicles are crucial steps in NA synthesis, leading to DMA synthesis and secretion in rice.

Iron deficiency regulated OsOPT7 is essential for iron homeostasis in rice.

The molecular mechanism of iron (Fe) uptake and transport in plants are well-characterized; however, many components of Fe homeostasis remain unclear. We cloned iron-deficiency-regulated oligopeptide transporter 7 (OsOPT7) from rice. OsOPT7 localized to the plasma membrane and did not transport Fe(III)-DMA or Fe(II)-NA and GSH in Xenopus laevis oocytes. Furthermore OsOPT7 did not complement the growth of yeast fet3fet4 mutant. OsOPT7 was specifically upregulated in response to Fe-deficiency. Promoter GUS analysis revealed that OsOPT7 expresses in root tips, root vascular tissue and shoots as well as during seed development. Microarray analysis of OsOPT7 knockout 1 (opt7-1) revealed the upregulation of Fe-deficiency-responsive genes in plants grown under Fe-sufficient conditions, despite the high Fe and ferritin concentrations in shoot tissue indicating that Fe may not be available for physiological functions. Plants overexpressing OsOPT7 do not exhibit any phenotype and do not accumulate more Fe compared to wild type plants. These results indicate that OsOPT7 may be involved in Fe transport in rice.