A neonatal mouse model of meconium peritonitis generated using human meconium slurry.

BACKGROUND: Meconium peritonitis is a noninfectious chemical peritonitis that occurs following fetal intestinal perforation and leakage of meconium into the abdominal cavity. Because of the lack of appropriate animal models, its pathophysiology has not yet been elucidated. We aimed to create a neonatal mouse model of meconium peritonitis using human meconium slurry (MS). METHODS: A stock MS solution prepared from fresh meconium obtained from healthy term infants was administered intraperitoneally to 4-d-old newborn mice. An MS LD40 was then administered, and changes in body weight, hematology, serum biochemistry, and immunomodulatory gene expression were determined. The MS was subjected to antibiotic treatment and heat inactivation to validate the content. Finally, comparisons with nonsurgical neonatal sepsis mouse models were performed. RESULTS: Dose-dependent mortality rates were observed, with an LD40 of 200 µL/body weight established. Substantial hematological and hepatorenal abnormalities and increased inflammatory gene expression were observed. Although antibiotic treatment was ineffective, the survival rate was improved by enzymatic inactivation of MS. Importantly, the systemic responses to MS were distinct from those observed in neonatal sepsis model mice. CONCLUSION: The MS model closely reflects the pathology of human neonatal meconium peritonitis and maybe useful in research elucidating the pathophysiology of this condition. IMPACT: In this study, we generated a neonatal mouse model of meconium peritonitis through intraperitoneal administration of human meconium slurry. We clarified that the pathogenic agent in meconium slurry is mainly a digestive enzyme, and that the systemic responses elicited by meconium slurry were distinct from those in a neonatal sepsis mouse model. As our mouse model is simple and highly reproducible, it is useful for elucidating the pathophysiology of meconium peritonitis.

Serum free carnitine levels in children with Kawasaki disease.

BACKGROUND: Carnitine plays an essential role in the transfer of long-chain fatty acids to the mitochondria for ß-oxidation. No study has characterized carnitine in children with Kawasaki disease (KD). The objective of this study was to elucidate the characteristics of serum free carnitine (FC) in hospitalized pediatric patients with KD. METHODS: We retrospectively analyzed 45 patients with KD in whom serum FC levels were measured. We investigated the clinical and laboratory parameters before intravenous immunoglobulin was administered, including serum FC levels, according to the response to intravenous immunoglobulin (IVIG). We also analyzed the relationship among serum FC, laboratory data, and clinical variables. RESULTS: IVIG was effective in 33 children (responders) and was ineffective in 12 children (non-responders). Serum FC levels were higher in non-responders than in responders: 35.3 µmol/L (range, 26.8-118.4 µmol/L) vs 31.4 µmol/L (range, 20.9-81.2 µmol/L), P <0.05. FC levels before IVIG in 80% of responders were below the normal range. The levels of aspartate aminotransferase (AST), alanine aminotransferase (ALT), total bilirubin, and FC were higher in non-responders than in responders. FC levels were correlated with AST (R2 = 0.364, P = 0.0015) and ALT (R2 = 0.423, P < 0.001) levels. CONCLUSIONS: Free carnitine levels were elevated in some patients with KD, especially in those who were refractory to IVIG. Additionally, FC levels in children with KD correlated with ASL and ALT levels.

Usefulness of brain natriuretic peptide to distinguish Kawasaki disease from cervical lymphadenitis.

BACKGROUND: Cervical lymphadenitis (CL) cannot be easily distinguished from Kawasaki disease (KD). We therefore explored whether brain natriuretic peptide (BNP) levels are useful in this context. METHODS: We retrospectively analyzed 14 children with CL and 177 children with KD. Patients with KD were divided into three groups according to their clinical symptoms at hospitalization - 97 patients had typical KD, 35 had node-first KD (NFKD), and 45 had KD without lymphadenopathy. We reviewed data on clinical and laboratory parameters, including serum BNP levels, at hospitalization together with factors that might distinguish KD from CL. RESULTS: Patients with CL were older than those with KD. Serum BNP levels were higher in all the KD groups than in the CL group. Multivariate logistic regression analyses indicated that higher BNP levels were associated with NFKD (odds ratio: 1.12, 95% confidence interval: 1.01-1.25). The receiver operating characteristic curve yielded a BNP cutoff of 18.3 pg/mL, with a sensitivity of 0.680, a specificity of 0.857, and an area under the curve of 0.806 (95% confidence interval: 0.665-0.947). CONCLUSIONS: Serum BNP levels can be used to distinguish KD from CL, especially in patients with NFKD.

Fractionation of Regenerated Silk Fibroin and Characterization of the Fractions.

The molecular weight (MW) of regenerated silk fibroin (RSF) decreases during degumming and dissolving processes. Although MW and the MW distribution generally affect polymer material processability and properties, few reports have described studies examining the influences of MW and the distribution on silk fibroin (SF) material. To prepare different MW SF fractions, the appropriate conditions for fractionation of RSF by ammonium sulfate (AS) precipitation process were investigated. The MW and the distribution of each fraction were found using gel permeation chromatography (GPC) and SDS-polyacrylamide electrophoresis (SDS-PAGE). After films of the fractionated SFs formed, the secondary structure, surface properties, and cell proliferation of films were evaluated. Nanofiber nonwoven mats and 3D porous sponges were fabricated using the fractionated SF aqueous solution. Then, their structures and mechanical properties were analyzed. The results showed AS precipitation using a dialysis membrane at low temperature to be a suitable fractionation method for RSF. Moreover, MW affects the nanofiber and sponge morphology and mechanical properties, although no influence of MW was observed on the secondary structure or crystallinity of the fabricated materials.

The Non-Mendelian Green Cotyledon Gene in Soybean Encodes a Small Subunit of Photosystem II.

Chlorophyll degradation plays important roles in leaf senescence including regulation of degradation of chlorophyll-binding proteins. Although most genes encoding enzymes of the chlorophyll degradation pathway have been identified, the regulation of their activity has not been fully understood. Green cotyledon mutants in legume are stay-green mutants, in which chlorophyll degradation is impaired during leaf senescence and seed maturation. Among them, the soybean (Glycine max) green cotyledon gene cytG is unique because it is maternally inherited. To isolate cytG, we extensively sequenced the soybean chloroplast genome, and detected a 5-bp insertion causing a frame-shift in psbM, which encodes one of the small subunits of photosystem II. Mutant tobacco plants (Nicotiana tabacum) with a disrupted psbM generated using a chloroplast transformation technique had green senescent leaves, confirming that cytG encodes PsbM. The phenotype of cytG was very similar to that of mutant of chlorophyll b reductase catalyzing the first step of chlorophyll b degradation. In fact, chlorophyll b-degrading activity in dark-grown cytG and psbM-knockout seedlings was significantly lower than that of wild-type plants. Our results suggest that PsbM is a unique protein linking photosynthesis in presenescent leaves with chlorophyll degradation during leaf senescence and seed maturation. Additionally, we discuss the origin of cytG, which may have been selected during domestication of soybean.

NYC4, the rice ortholog of Arabidopsis THF1, is involved in the degradation of chlorophyll - protein complexes during leaf senescence.

Yellowing/chlorophyll breakdown is a prominent phenomenon in leaf senescence, and is associated with the degradation of chlorophyll - protein complexes. From a rice mutant population generated by ionizing radiation, we isolated nyc4-1, a stay-green mutant with a defect in chlorophyll breakdown during leaf senescence. Using gene mapping, nyc4-1 was found to be linked to two chromosomal regions. We extracted Os07g0558500 as a candidate for NYC4 via gene expression microarray analysis, and concluded from further evidence that disruption of the gene by a translocation-related event causes the nyc4 phenotype. Os07g0558500 is thought to be the ortholog of THF1 in Arabidopsis thaliana. The thf1 mutant leaves show variegation in a light intensity-dependent manner. Surprisingly, the Fv /Fm value remained high in nyc4-1 during the dark incubation, suggesting that photosystem II retained its function. Western blot analysis revealed that, in nyc4-1, the PSII core subunits D1 and D2 were significantly retained during leaf senescence in comparison with wild-type and other non-functional stay-green mutants, including sgr-2, a mutant of the key regulator of chlorophyll degradation SGR. The role of NYC4 in degradation of chlorophyll and chlorophyll - protein complexes during leaf senescence is discussed.

A green-cotyledon/stay-green mutant exemplifies the ancient whole-genome duplications in soybean.

The recent whole-genome sequencing of soybean (Glycine max) revealed that soybean experienced whole-genome duplications 59 million and 13 million years ago, and it has an octoploid-like genome in spite of its diploid nature. We analyzed a natural green-cotyledon mutant line, Tenshin-daiseitou. The physiological analysis revealed that Tenshin-daiseitou shows a non-functional stay-green phenotype in senescent leaves, which is similar to that of the mutant of Mendel's green-cotyledon gene I, the ortholog of SGR in pea. The identification of gene mutations and genetic segregation analysis suggested that defects in GmSGR1 and GmSGR2 were responsible for the green-cotyledon/stay-green phenotype of Tenshin-daiseitou, which was confirmed by RNA interference (RNAi) transgenic soybean experiments using GmSGR genes. The characterized green-cotyledon double mutant d1d2 was found to have the same mutations, suggesting that GmSGR1 and GmSGR2 are D1 and D2. Among the examined d1d2 strains, the d1d2 strain K144a showed a lower Chl a/b ratio in mature seeds than other strains but not in senescent leaves, suggesting a seed-specific genetic factor of the Chl composition in K144a. Analysis of the soybean genome sequence revealed four genomic regions with microsynteny to the Arabidopsis SGR1 region, which included the GmSGR1 and GmSGR2 regions. The other two regions contained GmSGR3a/GmSGR3b and GmSGR4, respectively, which might be pseudogenes or genes with a function that is unrelated to Chl degradation during seed maturation and leaf senescence. These GmSGR genes were thought to be produced by the two whole-genome duplications, and they provide a good example of such whole-genome duplication events in the evolution of the soybean genome.

Determining the Treatment Strategy for Refractory Ulcerative Colitis Using Prostaglandin E-major Urinary Metabolite (PGE-MUM) Measurement.

Prostaglandin E-major urinary metabolite (PGE-MUM) is a valuable biomarker reflecting the cytokine profile. We encountered a case of a 14-year-old boy with pan-colitis-type ulcerative colitis who was unresponsive to steroids and infliximab. The patient's clinical symptoms gradually deteriorated and surgical treatment was strongly considered because anti-inflammatory therapy was unlikely to be effective. PGE-MUM levels were markedly elevated, indicating a T-helper 17 (Th17)-like cytokine profile. Because an antibody against interleukin 23 (IL-23) was presumed to be effective, the patient was treated with mirikizumab, after which he achieved remission. In the present case, measurement of PGE-MUM levels was useful in selecting anti-cytokine treatments for severe ulcerative colitis.

Biomechanical analysis of tendon regeneration capacity of Iberian ribbed newts following transection injury: Comparison to a mouse model.

Adult mammals are known for their poor ability to regenerate tissues, including tendons. On the other hand, urodeles have become an important model in regenerative studies for their remarkable ability to regenerate various body parts and organs throughout life, such as limbs, retinas, or even the brain. However, little is known about their capacity to regenerate injured tendons. If newts can also repair tendons without scar formation, they may be a suitable animal model for tendon regeneration studies in other adult vertebrates. Therefore, the present study used Iberian ribbed newts to characterize mechanical and structural regeneration of tendons following transection, using tensile tests and multiphoton microscopy. A digital flexor tendon in a hindlimb was transected either partially or completely, and regenerated tendon was examined 6 and 12 weeks after the operation. Tensile strength of regenerated tendons was significantly less than normal at 6 weeks, but was remarkably recovered at 12 weeks, reaching levels comparable to those of uninjured tendons. On the other hand, mouse tendons demonstrated poor recovery of strength even after 12 weeks. Multiphoton microscopy revealed that tendon-like collagenous tissue bridges residual tendon stubs in newts, but disorganized scar-like tissue filled the injured location in mice. These findings highlight the remarkable capacity of newts to recover from tendon injury and confirm the utility of newts as a model to study tendon regeneration.

The complete sequence of the chloroplast genome of Chrysanthemum rupestre, a diploid disciform capitula species of Chrysanthemum.

In this study, we analyzed the complete sequence of the chloroplast genome of Chrysanthemum rupestre Matsum. et Koidz., 1910, a diploid disciform capitula species of Chrysanthemum endemic to Japan, formerly classified as Ajania rupestris (Matsum. & Koidz.) Muldashev, Bot. Zhurn. (Moscow & Leningrad), 1983. The chloroplast genome of C. rupestre has a typical conserved quadripartite structure of 151,061 bp in length, comprising a large single-copy region (82,846 bp), a small single-copy region (18,301 bp), and a pair of inverted repeat regions (each 24,957 bp). Phylogenetic analysis indicated that C. rupestre clustered with other Chrysanthemum species, including another former Ajania species, Chrysanthemum pacificum Nakai, 1928. However, Ajania variifolia (C.C.Chang) Tzvelev, 1961, which is a synonym of Phaeostigma variifolium (C.C.Chang) Muldashev, 1981, was placed outside the Chrysanthemum clade, thereby implying that the former genus Ajania includes heterogeneous species.

Usefulness of Q-Probe PCR in Detecting Macrolide-Resistant Mycoplasma pneumoniae Infection in Children.

To investigate the usefulness of quenching probe polymerase chain reaction (Q-probe PCR) for the detection of macrolide-resistant Mycoplasma pneumoniae (MP), we retrospectively analyzed the clinical course of 21 children with MP infection. The rate of macrolide-resistant MP was 66.7%. The duration of pyrexia after the initial antibiotic treatment was longer in patients with macrolide-resistant MP infection than in those with macrolide-sensitive MP infection. The duration of pyrexia after Q-probe PCR was not significantly different between patients with macrolide-resistant and -sensitive MP infection. Antibiotic use based on qPCR may reduce the duration of pyrexia. Q-probe PCR is useful in determining the appropriate antibiotics and improves the clinical course of MP infections.

[Progressive or delayed early-onset pediatric sensorineural hearing loss].

The introduction of newborn-hearing screening has enabled early childhood hearing loss to be diagnosed and increased the number of children undergoing early care. Bilateral hearing loss is found in 0.08% of newborns and children whose hearing loss progresses or onset is delayed account for 4 to 30% of all pediatric hearing impairment. Children with perinatal risk factors tend to have deteriorated hearing or delayed-onset hearing loss in early childhood, necessitating audiometric follow-up. We also are aware of some children without risk factors who develop hearing impairment during infancy or early childhood. Hearing deterioration may be difficult to diagnose objectively, especially in young children, the presence of risk factors must be determines as soon as possible, especially given the lack of hearing management and close examination of children without apparent risk factors. We retrospectively studied children born from April 1998 to March 2007 and undergoing cochlear implantation as of April 2008. Among cases, we focused on 10 whose hearing impairment advanced during infancy -4 with risk factors known before hearing deterioration progressed, and 6 cases thought not to have any risk factors. We detected enlarged vestibular acquaduct in 3 of these 6 cases, and 3 more of whom had no risk factors -2 passing newborn-hearing screening and 1 in whom such screening detected hemilateral hearing loss. Our results underscore the need for early temporal computed tomography for detecting enlarged vestibular aquaduct. Even children with mild or hemilateral hearing loss should undergo audiometric and developmental testing at least every 6 months up to going to elementary school. Children suspected of impaired hearing should undergo thorough hearing tests regardless of newborn hearing-screening results to catch any problems early. Appropriate regular hearing and language development check-up tests must also be developed.

[Subsidizing hearing aid purchase in mild to moderate pediatric hearing--pediatric status following prefectural assembly subvention].

The dissemination of newborn hearing screening (NHS) has enabled those with mild to moderate hearing loss to be diagnosed in early infancy. The "handicapped independence support law", however, prevents those not determined to be physically handicapped; i.e., those with mild to moderate hearing loss-, from government assistance in purchasing hearing aids. This results either in (i) parents purchasing hearing aids at their own expense or (ii) nonpurchase of hearing aids. To redress this situation, subvention in purchasing hearing aids of mild to moderate hearing loss children has been begun by some local governments. We petitioned for such aid at the Okayama Prefecture Assembly. A society for supporting pediatric hearing difficulty in Okayama Prefecture also submitted a similar petition in September 2009, and subvention began in April 2010 for all such children in Okayama Prefecture. We report procedures and details leading to this subvention.

Prognostic factors for bone metastases from head and neck squamous cell carcinoma: A case series of 97 patients.

Although bone is the second-most frequent site of distant metastases of head and neck squamous cell carcinoma (HNSCC), variable prognostic factors in patients with bone metastases from HNSCC have not been fully investigated. The aim of the present study was to assess the prognostic factors affecting overall survival (OS) in these patients. The medical records of 97 patients at two institutions who developed bone metastases from HNSCC between January 2010 and December 2020 were retrospectively reviewed. A multivariate analysis using a Cox proportional hazards model was performed to identify potential clinical predictive factors for longer OS. The median OS was 7 months, and the 1- and 2-year OS rates for all patients were 35.4 and 19.2%, respectively. The independent predictive factors for longer OS were single bone metastasis, good performance status and administration of systemic chemotherapy. The median OS with each predictor was 10, 10 and 10.5 months, respectively. In a selected group of patients with these three factors, the OS was 14.5 months. In conclusion, single bone metastasis, a good performance status and systemic chemotherapy were independent predictors of longer OS in patients with HNSCC, but their contributions were limited.

Defect in non-yellow coloring 3, an alpha/beta hydrolase-fold family protein, causes a stay-green phenotype during leaf senescence in rice.

Chlorophyll degradation is an important phenomenon in the senescence process. It is necessary for the degradation of certain chlorophyll-protein complexes and thylakoid membranes during leaf senescence. Mutants retaining greenness during leaf senescence are known as 'stay-green' mutants. Non-functional type stay-green mutants, which possess defects in chlorophyll degradation, retain greenness but not leaf functionality during senescence. Here, we report a new stay-green mutant in rice, nyc3. nyc3 retained a higher chlorophyll a and chlorophyll b content than the wild-type but showed a decrease in other senescence parameters during dark incubation, suggesting that it is a non-functional stay-green mutant. In addition, a small amount of pheophytin a, a chlorophyll a-derivative without Mg(2+) ions in its tetrapyrrole ring, accumulated in the senescent leaves of nyc3. nyc3 shows a similar but weaker phenotype to stay green (sgr), another non-functional stay-green mutant in rice. The chlorophyll content of nyc3 sgr double mutants at the late stage of leaf senescence was also similar to that of sgr. Linkage analysis revealed that NYC3 is located near the centromere region of chromosome 6. Map-based cloning of genes near the centromere is very difficult because of the low recombination rate; however, we overcame this problem by using ionizing radiation-induced mutant alleles harboring deletions of hundreds of kilobases. Thus, it was revealed that NYC3 encodes a plastid-localizing alpha/beta hydrolase-fold family protein with an esterase/lipase motif. The possible function of NYC3 in the regulation of chlorophyll degradation is discussed.

Genetic Interaction Among Phytochrome, Ethylene and Abscisic Acid Signaling During Dark-Induced Senescence in Arabidopsis thaliana.

Leaf senescence is induced by various internal and external stimuli. Dark-induced senescence has been extensively investigated, but the detailed mechanism underlying it is not well understood. The red light/far-red light receptor phytochrome B and its downstream transcription factors, PYHTOCHROME INTERACTING FACTORs (PIFs) 4 and 5, are known to play an important role in dark-induced senescence. Furthermore, the senescence-inducing phytohormones, ethylene and abscisic acid (ABA) are reported to be involved in dark-induced senescence. In this study, we analyzed the relationship between ethylene, ABA and PIFs in dark-induced leaf senescence. A triple mutant of the core ABA signaling components; SNF1-related protein kinases 2D (SRK2D), SRK2E, and SRK2I, displayed an ABA insensitive phenotype in ABA-induced senescence, whilst the ethylene insensitive mutant ein2 demonstrated low sensitivity to ABA, suggesting that ethylene signaling is involved in ABA-induced senescence. However, the pif4 pif5 mutant did not display low sensitivity to ABA, suggesting that PIF4 and PIF5 act upstream of ABA signaling. Although PIF4 and PIF5 reportedly regulate ethylene production, the triple mutant ein2 pif4 pif5 showed a stronger delayed senescence phenotype than ein2 or pif4 pif5, suggesting that EIN2 and PIF4/PIF5 partially regulate leaf senescence independently of each other. While direct target genes for PIF4 and PIF5, such as LONG HYPOCOTYL IN FAR-RED1 (HFR1) and PHYTOCHROME INTERACTING FACTOR 3-LIKE 1 (PIL1), showed transient upregulation under dark conditions (as is seen in the shade avoidance response), expression of STAY GREEN1 (SGR1), ORESARA1 (ORE1) and other direct target genes of PIF5, continued to increase during dark incubation. It is possible that transcription factors other than PIF4 and PIF5 are involved in the upregulation of SGR1 and ORE1 at a later stage of dark-induced senescence. Possible candidates are senescence-induced senescence regulators (SIRs), which include the NAC transcription factors ORE1 and AtNAP. In fact, ORE1 is known to bind to the SGR1 promoter and promotes its expression. It is therefore inferred that the phytochrome-PIF pathway regulates initial activation of senescence and subsequently, induced SIRs reinforce leaf senescence during dark-induced senescence.

Procalcitonin as a Biomarker of Unresponsiveness to Intravenous Immunoglobulin for Kawasaki Disease.

OBJECTIVE: To investigate the usefulness of procalcitonin (PCT) as predictive factors of intravenous immunoglobulin (IVIG)-resistant Kawasaki disease patients. METHODS: We retrospectively analyzed the laboratory data from 215 children with Kawasaki disease treated with IVIG from 2014 to 2019. We analyzed the clinical and laboratory parameters just before the IVIG including serum levels of PCT with respect to the IVIG response. RESULTS: Eventually, 127 patients were analyzed. The median age was 2.4 years. IVIG was effective in 108 children (responders) and was ineffective in 19 (non-responders). Serum PCT concentration was higher in non-responders than those of responders (P < 0.001). Multivariate logistic regression analyses indicated that higher PCT concentration (odds ratio 1.34, 95% confidence interval 1.10-1.64) were associated with IVIG resistance. Analyses of the receiver operating characteristic curve showed that the cutoff value of PCT 2.18 ng/mL had 46.4% of sensitivity and 93.9% of specificity. Receiver operating characteristic analysis yielded an area under the curve of 0.82 (0.72-0.92) to predict IVIG resistance. CONCLUSIONS: Serum PCT value can be an excellent biomarker for predicting unresponsiveness to IVIG with a good discriminatory ability as well as the existing prediction scores.

White Blood Cell and Neutrophil Counts and Response to Intravenous Immunoglobulin in Kawasaki Disease.

We explored parameters to predicting the efficacy of intravenous immunoglobulin (IVIG) therapy for patients with Kawasaki disease (KD). We retrospectively analyzed the laboratory data of 77 children with KD treated with IVIG. Data obtained before and within 24 hours after IVIG therapy were compared between responders and nonresponders. The white blood cell (WBC) and neutrophil counts were significantly lower in responders than nonresponders within 24 hours after IVIG. The areas under the receiver operating characteristics curves of the WBC and neutrophil counts were 0.846 and 0.754, respectively. The WBC and neutrophil counts differed significantly between responders and nonresponders (the latter developed recurrent pyrexia after transient fever resolution). In conclusion, WBC and neutrophil counts within 24 hours after IVIG usefully predict the efficacy of IVIG therapy for those with KD, and identify nonresponders to such therapy.