RESUMO
Mutualism profoundly affects the morphology and ecological evolution of both hosts and symbionts involved. Heterocyathus is a solitary scleractinian coral that lives on soft substrata, and sipunculan worms live symbiotically in the tube-like cavities (orifice) inside the coral skeletons. This habitat provides protection to the sipunculan worms against predators and-owing to the mobility of the worms-prevents the coral from being buried with sediments. The orifice growth is closely related to the symbiont sipunculan worms; however, this has not been previously elucidated. Here, we clarified the growth process of scleractinian coral orifices and the influence of sipunculan activity on this. The orifices were originally formed by rapid accretion deposits. The coral soft tissue enveloping the growth edge of the orifice repeatedly retreated to the outer side due to direct damage to the soft part and/or excessive stress caused by the rubbing of the sipunculan through locomotion, excretion, and feeding behaviour. This resulted in a toppled-domino microskeletal structure appearance and maintenance of the orifice growth. These outcomes demonstrate the first example of the direct influence of symbionts on the skeletal morphogenesis of scleractinian corals. The mutualism between the two organisms is maintained by the beneficial confrontation in forming orifices.
Assuntos
Antozoários , Simbiose , Animais , Antozoários/fisiologia , Antozoários/crescimento & desenvolvimento , Simbiose/fisiologia , Adaptação Fisiológica , Ecossistema , Recifes de CoraisRESUMO
Zeolites catalyze some reactions in their molecular-sized pores, but large molecules can react only on their external surface. Zeolite-nanosheets (NSs) have been developed as catalysts for large molecules. The previously reported methods to synthesize zeolite-NSs are specialized for each zeolite type. Here we propose a new method to synthesize various zeolite-NSs from the same amorphous aluminosilicate NSs (AAS-NSs) as a universal precursor. We successfully synthesized the unprecedented AAS-NSs in the hydrophilic space of the stable hyperswollen lyotropic lamellar (HL) phase. The four zeolite types could be obtained from the single-species AAS-NSs. These results imply that this method enables us to synthesize almost all types of zeolite-NSs. Moreover, the synthesized CHA-NSs have great potential for various applications because of their thickness and large external surface area.
RESUMO
The azooxanthellate solitary scleractinian Deltocyathoides orientalis (family Turbinoliidae), which has bowl-shaped costate corallites, exhibits burrowing behavior on soft substrates and can adapt to an infaunal mode of life. Here, we describe previously unknown aspects of their life history and asexual mode of reproduction based on morphological and molecular phylogenetic analyses. The findings reveal that (1) D. orientalis exhibits asexual reproduction by transverse division; (2) smaller bowl-shaped costate anthocyathus derived from cylindrical to tympanoid anthocaulus were attached to hard substrates, including shell fragments and gravels on soft substrates; and (3) anthocyathus only reproduce sexually after division, and anthocaulus was found to regrow and repeatedly produce anthocyathi through transverse division. The bowl-shaped corallum morphology of the anthocyathus just after division might reduce the time required for skeletal formation to enable infaunal adaption after transverse division. Immediately after division, D. orientalis can smoothly shift to a burrowing lifestyle that efficiently utilizes soft-substrate environments, thus increasing its survival rate. The morphological formation of prospective anthocyathus in the anthocaulus stage is consequently thought to involve an increase in clonal individuals as well as adaptations for a burrowing free-living mode of life in the anthocyathus stage.
Assuntos
Antozoários , Animais , Antozoários/anatomia & histologia , Estágios do Ciclo de Vida , Filogenia , Estudos Prospectivos , Reprodução AssexuadaRESUMO
Sagami Bay and Suruga Bay harbor a rich marine biodiversity; however, their outer-shelf scleractinian coral fauna has not been characterized to date. Scleractinian corals were collected by dredge sampling of the Japanese Association for Marine Biology (JAMBIO) Coastal Organisms Joint Surveys in 2015 to elucidate the diversity of azooxanthellate scleractinian corals from the outer shelf zones of Sagami Bay and Suruga Bay. In this study, a total of 1291 azooxanthellate scleractinian specimens were collected, corresponding to 23 genera and 18 species, five of which are new records for Sagami Bay and eight are new records for Suruga Bay. Moreover, in all localities, except sampling locality (SL) 8, more than 70% of the specimens showed asexual reproduction. This finding suggests that asexual reproduction may play an important role in increasing the coral population size in soft-substrate environments of the outer shelf.
Assuntos
Antozoários , Animais , Baías , Biodiversidade , JapãoRESUMO
We have previously shown that ascorbic acid (AsA) deficiency elevates hepatic expression of acute phase proteins (APPs), inflammatory markers, in Osteogenic Disorder Shionogi (ODS) rats, which are unable to synthesize AsA. However, the precise mechanisms of this elevation are unknown. Signal transducer and activator of transcription 3 (STAT3) is one of the transcription factors inducing the expression of APPs and is activated by several cytokines including interleukin-6 (IL-6). The aim of this study was to determine whether AsA deficiency stimulates hepatic STAT3 activation and increases intestinal production of proinflammatory cytokines such as IL-6. Male ODS rats (6 weeks old) were fed either a basal diet containing 300 mg AsA/kg (control group) or an AsA-free diet (AsA-deficient group) for 18 days. AsA deficiency gradually and simultaneously elevated both mRNA levels of APPs (haptoglobin, α1-acid glycoprotein, C-reactive protein and α2-macroglobulin) and nuclear level of phosphorylated STAT3 (activated STAT3) in the liver. These results showed that the AsA-deficiency-induced expression of hepatic APPs is stimulated by proinflammatory cytokines activating STAT3. On day 14, AsA deficiency significantly elevated IL-6 mRNA level in the ileum and the concentration of IL-6 in portal blood. Furthermore, the portal concentration of IL-6 positively correlated with hepatic mRNA levels of STAT3-regulated genes. These findings suggest that IL-6, produced in the intestine as a result of AsA deficiency, is recruited to the liver via the portal vein and contributes to hepatic STAT3 activation and the elevated expression of APPs.
Assuntos
Proteínas de Fase Aguda/metabolismo , Deficiência de Ácido Ascórbico/fisiopatologia , Interleucina-6/metabolismo , Fígado/metabolismo , Fator de Transcrição STAT3/metabolismo , Animais , Ácido Ascórbico/farmacologia , Núcleo Celular/metabolismo , Citosol/metabolismo , Duodeno/metabolismo , Perfilação da Expressão Gênica , Inflamação , Masculino , Osteogênese , Fosforilação , RatosRESUMO
The aim of this study was to verify the protective effects of ascorbic acid (AsA) against lipopolysaccharide (LPS)-induced sepsis. The study was conducted using osteogenic disorder Shionogi (ODS) rats, which are unable to synthesize AsA. Male ODS rats (6 wk old) were fed either an AsA-free diet (AsA-deficient group), a diet supplemented with 300 mg/kg AsA (control group), or a diet supplemented with 3,000 mg/kg AsA (high-AsA group) for 8 d. On day 8, all the rats were intraperitoneally injected with LPS (15 mg/kg body weight). Forty-eight hours after the injection, the survival rates of the rats in the control (39%) and the high-AsA (61%) groups were significantly higher than that in the AsA-deficient group (5.5%). Next, we measured several inflammatory parameters during 10 h after administering LPS. At 6 h, elevated serum levels of markers for hepatic and systemic injuries were suppressed in rats fed AsA. Similarly, 10 h after LPS injection, the elevation in the serum levels of markers for renal injury were also suppressed proportionally to the amount of AsA in the diet. The elevated serum concentrations of TNFα and IL-1ß by LPS in the AsA-deficient group decreased in groups fed AsA. Hematic TNFα mRNA levels at 6 h after the LPS injection were also lowered by feeding AsA. These results demonstrated that the dietary intake of AsA improved the survival rates and suppressed the inflammatory damage, in a dose-dependent manner, caused during sepsis induced by LPS in ODS rats.
Assuntos
Ácido Ascórbico/uso terapêutico , Suplementos Nutricionais , Inflamação/prevenção & controle , Rim/efeitos dos fármacos , Fígado/efeitos dos fármacos , Sepse/tratamento farmacológico , Vitaminas/uso terapêutico , Animais , Anti-Inflamatórios/administração & dosagem , Anti-Inflamatórios/sangue , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Ácido Ascórbico/administração & dosagem , Ácido Ascórbico/sangue , Ácido Ascórbico/farmacologia , Deficiência de Ácido Ascórbico/sangue , Deficiência de Ácido Ascórbico/complicações , Deficiência de Ácido Ascórbico/genética , Deficiência de Ácido Ascórbico/prevenção & controle , Dieta , Inflamação/induzido quimicamente , Interleucina-1beta/sangue , Nefropatias/sangue , Nefropatias/etiologia , Nefropatias/prevenção & controle , Lipopolissacarídeos , Hepatopatias/sangue , Hepatopatias/etiologia , Hepatopatias/prevenção & controle , Masculino , Estado Nutricional , Osteogênese/fisiologia , Ratos , Ratos Endogâmicos , Sepse/induzido quimicamente , Sepse/complicações , Fator de Necrose Tumoral alfa/sangue , Vitaminas/administração & dosagem , Vitaminas/sangue , Vitaminas/farmacologiaRESUMO
Asexual reproduction is one of the most important traits in the evolutionary history of corals. No real-time observations of asexual reproduction in azooxanthellate solitary scleractinian corals have been conducted to date. Here, we describe previously unknown aspects of asexual reproduction by using Truncatoflabellum spheniscus (Family Flabellidae) based on observations of transverse division conducted over 1200 days. The findings revealed that (1) transverse division was caused by decalcification; (2) compared to the anthocyathus (upper part of the divided corallum), the soft parts of the anthocaulus (lower part of the divided corallum) were severely damaged and injured during division; (3) these injuries were repaired rapidly; and (4) the anthocaulus regrew and repeatedly produced anthocyathi by means of transverse division. Differences in the patterns of soft-part regeneration and repair, as well as differences in skeletal growth rates between the anthocaulus and the anthocyathus imply that the ecological requirements and reproductive success are different from each other immediately after division. The findings provide important clues for unravelling why asexual reproduction appeared frequently in free-living corals, and the extent to which those modes of reproduction has affected the adaptive and evolutionary success of scleractinian corals throughout the Phanerozoic.
Assuntos
Antozoários/fisiologia , Evolução Biológica , Reprodução Assexuada , Animais , Regeneração , Esqueleto/metabolismoRESUMO
BACKGROUND AND STUDY AIMS: Endoscopic submucosal dissection (ESD) has become widely accepted as a minimally invasive treatment for early gastric cancer (EGC), and opportunities to use ESD to treat EGC in elderly patients are increasing. The objective of this study was to elucidate the safety and efficacy of ESD in elderly patients. PATIENTS AND METHODS: Between April 2006 and March 2013, a total of 892 patients with EGC were prospectively recruited to undergo ESD according to definite inclusion criteria. The short-term outcomes and incidence of complications in 345 of these patients who were 75 years of age or older (elderly group) were compared with the short-term outcomes and incidence of complications in the remaining 547 patients (non-elderly group). Factors associated with the occurrence of pneumonia and delirium were also investigated. RESULTS: The R0 resection rate did not differ between the two groups (96.2â% in the elderly group vs. 96.7â% in the non-elderly group; Pâ=â0.65). The incidence of pneumonia (7.5â% vs. 1.8â%; Pâ<â0.01) and incidence of delirium (10.1â% vs. 1.1â%; Pâ<â0.01) were significantly higher in the elderly group.âThe incidence of post-ESD bleeding and incidence of perforation were similar in the two groups. No emergency surgery was required, but one patient in the non-elderly group died of aspiration pneumonia. On multivariate analysis, age 75 years or older, cerebrovascular disease, chronic obstructive pulmonary disease, delirium, and remnant stomach or gastric tube were independent risk factors for pneumonia, and age 75 years or older, diabetes, dementia, and pneumonia were independent risk factors for delirium. CONCLUSION: ESD for EGC was feasible for elderly patients in good condition. However, pneumonia and delirium may develop more frequently after ESD in elderly patients with co-morbidities.
RESUMO
We describe a previously unknown niche for hard corals in the small, bowl-shaped, solitary scleractinian, Deltocyathoides orientalis (Family Turbinoliidae), on soft-bottom substrates. Observational experiments were used to clarify how the sea floor niche is exploited by turbinoliids. Deltocyathoides orientalis is adapted to an infaunal mode of life and exhibits behaviours associated with automobility that include burrowing into sediments, vertical movement through sediments to escape burial, and recovery of an upright position after being overturned. These behaviours were achieved through repeated expansion and contraction of their peripheral soft tissues, which constitute a unique muscle-membrane system. Histological analysis showed that these muscle arrangements were associated with deeply incised inter-costal spaces characteristic of turbinoliid corals. The oldest known turbinoliid, Bothrophoria ornata, which occurred in the Cretaceous (Campanian), also possessed a small, conical skeleton with highly developed costae. An infaunal mode of life became available to turbinoliids due to the acquisition of automobility through the muscle-membrane system at least 80 million years ago. The newly discovered active burrowing strategies described herein provide new insights into the use of an unattached mode of life by corals inhabiting soft-bottom substrates throughout the Phanerozoic.
Assuntos
Antozoários/anatomia & histologia , Antozoários/fisiologia , Sedimentos Geológicos , Animais , Histocitoquímica , Japão , Locomoção , Oceano PacíficoRESUMO
OBJECTIVE: The aim of this study was to determine whether ascorbic acid (AsA) deficiency-induced endotoxin influx into portal blood from the gastrointestinal tract contributes to the inflammatory changes in the liver. METHOD: The mechanisms by which AsA deficiency provokes inflammatory changes in the liver were investigated in Osteogenic Disorder Shionogi (ODS) rats (which are unable to synthesize AsA). Male ODS rats (6-wk-old) were fed a diet containing sufficient (300 mg/kg) AsA (control group) or a diet without AsA (AsA-deficient group) for 14 or 18 d. RESULTS: On day 14, the hepatic mRNA levels of acute-phase proteins and inflammation-related genes were significantly higher in the AsA-deficient group than the control group, and these elevations by AsA deficiency were exacerbated on day 18. The serum concentrations of interleukin (IL)-1ß and IL-6, which induce acute-phase proteins in the liver, were also significantly elevated on day 14 in the AsA-deficient group compared with the respective values in the control group. IL-1ß mRNA levels in the liver, spleen, and lung were increased by AsA deficiency. Moreover, on both days 14 and 18, the portal blood endotoxin concentration was significantly higher in the AsA-deficient group than in the control group, and a significant correlation between serum IL-1ß concentrations and portal endotoxin concentrations was found in AsA-deficient rats. In the histologic analysis of the ileum tissues, the number of goblet cells per villi was increased by AsA deficiency. CONCLUSION: These results suggest that AsA deficiency-induced endotoxin influx into portal blood from the gastrointestinal tract contributes to the inflammatory changes in the liver.
Assuntos
Deficiência de Ácido Ascórbico/sangue , Endotoxinas/sangue , Fígado/fisiopatologia , Animais , Endotoxemia/patologia , Íleo/metabolismo , Inflamação/patologia , Interleucina-1beta/sangue , Interleucina-1beta/metabolismo , Interleucina-6/sangue , Fígado/metabolismo , Hepatopatias/patologia , Pulmão/metabolismo , Masculino , Tamanho do Órgão , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos , Baço/metabolismoRESUMO
The mechanisms underlying the decrease in hepatic cytochrome P-450 (CYP) content in ascorbic acid deficiency was investigated in scurvy-prone ODS rats. First, male ODS rats were fed a diet containing sufficient ascorbic acid (control) or a diet without ascorbic acid (deficient) for 18 days, with or without the intraperitoneal injection of phenobarbital. Ascorbic acid deficiency decreased hepatic microsomal total CYP content, CYP2B1/2B2 protein, and mitochondrial cytochrome oxidase (COX) complex IV subunit I protein, and simultaneously increased heme oxygenase-1 protein in microsomes and mitochondria. Next, heme oxygenase-1 inducers, that is lipopolysaccharide and hemin, were administered to phenobaribital-treated ODS rats fed sufficient ascorbic acid. The administration of these inducers decreased hepatic microsomal total CYP content, CYP2B1/2B2 protein, and mitochondrial COX complex IV subunit I protein. These results suggested that the stimulation of hepatic heme oxygenase-1 expression by ascorbic acid deficiency caused the decrease in CYP content in liver.