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1.
JACS Au ; 4(4): 1385-1395, 2024 Apr 22.
Article in English | MEDLINE | ID: mdl-38665671

ABSTRACT

Brown algae play essential roles ecologically, practically, and evolutionarily because they maintain coastal areas, capture carbon dioxide, and produce valuable chemicals such as therapeutic drugs. To unlock their full potential, understanding the unique molecular biology of brown algae is imperative. Genetic engineering tools that regulate homeostasis in brown algae are essential for determining their biological mechanisms in detail. However, few methodologies have been developed to control gene expression due to the robust structural barriers of brown algae. To address this issue, we designed peptide-based, small interfering RNA (siRNA)-loaded micelles decorated with phenylboronic acid (PBA) ligands. The PBA ligands facilitated the cellular uptake of the micelles into a model brown alga, Ectocarpus siliculosus (E. Siliculosus), through chemical interaction with polysaccharides in the cell wall and biological recognition by boronic acid transporters on the plasma membrane. The micelles, featuring "kill two birds with one stone" ligands, effectively induced gene silencing related to auxin biosynthesis. As a result, the growth of E. siliculosus was temporarily inhibited without persistent genome editing. This study demonstrated the potential for exploring the characteristics of brown algae through a simple yet effective approach and presented a feasible system for delivering siRNA in brown algae.

2.
Plants (Basel) ; 12(18)2023 Sep 15.
Article in English | MEDLINE | ID: mdl-37765437

ABSTRACT

The present study provides new insights into the growth of the brown algal cell wall by showing that cell wall polysaccharides play an important role in the process of growth, considering the physicochemical characteristic of young and old Cladosiphon okamuranus. To determine its structural variation in detail, the cell wall was sequentially fractionated into five fractions: hot water (HW), ammonium oxalate, hemicellulose-I (HC-I), HC-II, and cellulose, and analyzed physicochemically. Results showed that almost 80% of the total recovery cell wall from both young and old thalli was HW, and HC-I contained mainly fucoidan composed of Fucose, Glucuronic acid, and sulfate in molar ratios of 1.0:0.3:0.6~0.7 and 1.0:0.3:0.2~0.3, respectively. Fucoidan in HW was a highly sulfated matrix polysaccharide abundance in young thalli, while fucoidan in HC-I was rich in old thalli and functions as hemicellulose in land plants, crosslinking with cellulose and strengthening the cell wall. We found that HW and HC-I were particularly involved in the growth and strength of old thalli appeared to be due to the deposition of HC-I and the reduction in water content during the growth process.

3.
Arch Oral Biol ; 155: 105797, 2023 Nov.
Article in English | MEDLINE | ID: mdl-37633030

ABSTRACT

OBJECTIVE: This study aimed to evaluate the role of ruxolitinib in the interferon beta (IFN-ß) mediated osteoblast differentiation using human dental pulp stem cells (hDPSCs). DESIGN: hDPSCs from five deciduous teeth of healthy patients were stimulated by adding human recombinant IFN-ß protein (1 or 2 ng/ml) to the osteogenic differentiation induction medium. Substrate formation was determined using Alizarin Red staining, calcium concentration, and osteoblast marker expression levels. Ruxolitinib was used to inhibit the Janus kinase/signal transducers and activators of transcription (JAK-STAT) pathway. Apoptosis was detected using terminal deoxynucleotidyl nick-end labeling (TUNEL) staining, and necroptosis was detected using propidium iodide staining and phosphorylated mixed lineage kinase domain-like protein (pMLKL) expression. RESULTS: In the IFN-ß-treated group, substrate formation was inhibited by a reduction in alkaline phosphatase (ALP) expression in a concentration-dependent manner. Although the proliferation potency was unchanged between the IFN-ß-treated and control groups, the cell number was significantly reduced in the experimental group. TUNEL-positive cell number was not significantly different; however, the protein level of necroptosis markers, interleukin-6 (IL-6) and pMLKL were significantly increased in the substrate formation. Cell number and ALP expression level were improved in the group administered ruxolitinib, a JAK-STAT inhibitor. Additionally, ruxolitinib significantly suppressed IL-6 and pMLKL levels. CONCLUSION: Ruxolitinib interfered with the IFN-ß-mediated necroptosis and osteogenic differentiation via the JAK-STAT pathway.

4.
Photosynth Res ; 156(2): 217-229, 2023 May.
Article in English | MEDLINE | ID: mdl-36862281

ABSTRACT

Carbonic anhydrase (CA) is a crucial component for the operation of CO2-concentrating mechanisms (CCMs) in the majority of aquatic photoautotrophs that maintain the global primary production. In the genome of the centric marine diatom, Thalassiosira pseudonana, there are four putative gene sequences that encode θ-type CA, which was a type of CA recently identified in marine diatoms and green algae. In the present study, specific subcellular locations of four θCAs, TpθCA1, TpθCA2, TpθCA3, and TpθCA4 were determined by expressing GFP-fused proteins of these TpθCAs in T. pseudonana. As a result, C-terminal GFP fusion proteins of TpθCA1, TpθCA2, and TpθCA3 were all localized in the chloroplast; TpθCA2 was at the central chloroplast area, and the other two TpθCAs were throughout the chloroplast. Immunogold-labeling transmission electron microscopy was further performed for the transformants expressing TpθCA1:GFP and TpθCA2:GFP with anti-GFP-monoclonal antibody. TpθCA1:GFP was localized in the free stroma area, including the peripheral pyrenoid area. TpθCA2:GFP was clearly located as a lined distribution at the central part of the pyrenoid structure, which was most likely the pyrenoid-penetrating thylakoid. Considering the presence of the sequence encoding the N-terminal thylakoid-targeting domain in the TpθCA2 gene, this localization was likely the lumen of the pyrenoid-penetrating thylakoid. On the other hand, TpθCA4:GFP was localized in the cytoplasm. Transcript analysis of these TpθCAs revealed that TpθCA2 and TpθCA3 were upregulated in atmospheric CO2 (0.04% CO2, LC) levels, while TpθCA1 and TpθCA4 were highly induced under 1% CO2 (HC) condition. The genome-editing knockout (KO) of TpθCA1, by CRISPR/Cas9 nickase, gave a silent phenotype in T. pseudonana under LC-HC conditions, which was in sharp agreement with the case of the previously reported TpθCA3 KO. In sharp contrast, TpθCA2 KO is so far unsuccessful, suggesting a housekeeping role of TpθCA2. The silent phenotype of KO strains of stromal CAs suggests that TpαCA1, TpθCA1, and TpθCA3 may have functional redundancy, but different transcript regulations in response to CO2 of these stromal CAs suggest in part their independent roles.


Subject(s)
Carbonic Anhydrases , Diatoms , Diatoms/genetics , Diatoms/metabolism , Carbonic Anhydrases/genetics , Carbonic Anhydrases/metabolism , Carbon Dioxide/metabolism , Chloroplasts/metabolism , Proteins/metabolism
5.
Microorganisms ; 11(2)2023 Feb 03.
Article in English | MEDLINE | ID: mdl-36838362

ABSTRACT

Linus Pauling, who was awarded the Nobel Prize in Chemistry, suggested that a high dose of vitamin C (l-ascorbic acid) might work as a prevention or treatment for the common cold. Vitamin C therapy was tested in clinical trials, but clear evidence was not found at that time. Although Pauling's proposal has been strongly criticized for a long time, vitamin C therapy has continued to be tested as a treatment for a variety of diseases, including coronavirus infectious disease 2019 (COVID-19). The pathogen of COVID-19, SARS-CoV-2, belongs to the ß-coronavirus lineage, which includes human coronavirus, severe acute respiratory syndrome (SARS), and Middle East respiratory syndrome (MERS). This review intends to shed new light on vitamin C antiviral activity that may prevent SARS-CoV-2 infection through the chemical production of nitric oxide (NO). NO is a gaseous free radical that is largely produced by the enzyme NO synthase (NOS) in cells. NO produced by upper epidermal cells contributes to the inactivation of viruses and bacteria contained in air or aerosols. In addition to enzymatic production, NO can be generated by the chemical reduction of inorganic nitrite (NO2-), an alternative mechanism for NO production in living organisms. Dietary vitamin C, largely contained in fruits and vegetables, can reduce the nitrite in saliva to produce NO in the oral cavity when chewing foods. In the stomach, salivary nitrite can also be reduced to NO by vitamin C secreted from the epidermal cells of the stomach. The strong acidic pH of gastric juice facilitates the chemical reduction of salivary nitrite to produce NO. Vitamin C contributes in multiple ways to the host innate immune system as a first-line defense mechanism against pathogens. Highlighting chemical NO production by vitamin C, we suggest that controversies on the therapeutic effects of vitamin C in previous clinical trials may partly be due to less appreciation of the pleiotropic functions of vitamin C as a universal bioreductant.

6.
JAMA Netw Open ; 6(2): e230589, 2023 02 01.
Article in English | MEDLINE | ID: mdl-36826818

ABSTRACT

Importance: There have been few studies on the heterogeneous interconnection of COVID-19 outbreaks occurring in different social settings using robust, surveillance epidemiological data. Objectives: To describe the characteristics of COVID-19 transmission within different social settings and to evaluate settings associated with onward transmission to other settings. Design, Setting, and Participants: This is a case series study of laboratory-confirmed COVID-19 cases in Tokyo between January 23 and December 5, 2020, when vaccination was not yet implemented. Using epidemiological investigation data collected by public health centers, epidemiological links were identified and classified into 7 transmission settings: imported, nightlife, dining, workplace, household, health care, and other. Main Outcomes and Measures: The number of cases per setting and the likelihood of generating onward transmissions were compared between different transmission settings. Results: Of the 44 054 confirmed COVID-19 cases in this study, 25 241 (57.3%) were among male patients, and the median (IQR) age of patients was 36 (26-52) years. Transmission settings were identified in 13 122 cases, including 6768 household, 2733 health care, and 1174 nightlife cases. More than 6600 transmission settings were detected, and nightlife (72 of 380 [18.9%]; P < .001) and health care (119 [36.2%]; P < .001) settings were more likely to involve 5 or more cases than dining, workplace, household, and other settings. Nightlife cases appeared in the earlier phase of the epidemic, while household and health care cases appeared later. After adjustment for transmission setting, sex, age group, presence of symptoms, and wave, household and health care cases were less likely to generate onward transmission compared with nightlife cases (household: adjusted odds ratio, 0.03; 95% CI, 0.02-0.05; health care: adjusted odds ratio, 0.57; 95% CI, 0.41-0.79). Household settings were associated with intergenerational transmission, while nonhousehold settings mainly comprised transmission between the same age group. Among 30 932 cases without identified transmission settings, cases with a history of visiting nightlife establishments were more likely to generate onward transmission to nonhousehold settings (adjusted odds ratio, 5.30 [95% CI, 4.64-6.05]; P < .001) than those without such history. Conclusions and Relevance: In this case series study, COVID-19 cases identified in nightlife settings were associated with a higher likelihood of spreading COVID-19 than household and health care cases. Surveillance and interventions targeting nightlife settings should be prioritized to disrupt COVID-19 transmission, especially in the early stage of an epidemic.


Subject(s)
COVID-19 , Humans , Male , Adult , Middle Aged , SARS-CoV-2 , Tokyo , Japan , Disease Outbreaks
7.
Carbohydr Res ; 523: 108722, 2023 Jan.
Article in English | MEDLINE | ID: mdl-36459703

ABSTRACT

Brown algae contain a polysaccharide-rich cell wall, mainly composed of alginate and fucoidan which have been extensively studied for their individual structure and bioactivities. Particularly, the cell wall of Cladosiphon okamuranus is rich in fucoidan rather than alginate. However, little is known about its arrangement or interlinking with other polysaccharides such as cellulose in the cell wall. To determine its structure in detail, the cell wall was sequentially fractionated into five fractions: hot water (HW), ammonium oxalate, hemicellulose-I (HC-I), HC-II, and cellulose. Almost 80% of the total cell wall recovered from alcohol insoluble residue in C. okamuranus consisted of HW and HC-I, which mainly contained fucoidan composed of fucose, glucuronic acid, and sulfate in molar ratios of 1.0:0.3:0.9 and 1.0:0.2:0.3, respectively. Methylation analysis revealed that fucoidan in HW and HC-I structurally differed in terms of content of sulfate, and sugar residue which was 1,4-linked xylose and 1,4-linked fucose. Small angle X-ray scattering measurements also showed distinct conformational differences between HW and HC-I. These structural heterogeneities of fucoidan may be related to their localization, and fucoidan in HC-I may be involved in reinforcing cell wall structure by cross-linking to cellulose.


Subject(s)
Fucose , Phaeophyceae , Phaeophyceae/chemistry , Polysaccharides/chemistry , Cellulose , Alginates , Cell Wall , Sulfates
8.
Phys Med Biol ; 67(19)2022 09 29.
Article in English | MEDLINE | ID: mdl-36096113

ABSTRACT

We propose a method to detect primary and metastatic lesions with Fluorine-18 fluorodeoxyglucose (FDG) accumulation in the lung field, neck, mediastinum, and bony regions on the FDG-PET/CT images. To search for systemic lesions, various anatomical structures must be considered. The proposed method is addressed by using an extraction process for anatomical regions and a uniform lesion detection approach. The uniform approach does not utilize processes that reflect any region-specific anatomical aspects but has a machine-learnable framework. Therefore, it can work as a lesion detection process for a specific anatomical region if it machine-learns the specific region data. In this study, three lesion detection processes for the whole-body bone region, lung field, or neck-mediastinum region are obtained. These detection processes include lesion candidate detection and false positive (FP) candidate elimination. The lesion candidate detection is based on a voxel anomaly detection with a one-class support vector machine. The FP candidate elimination is performed using an AdaBoost classifier ensemble. The image features used by the ensemble are selected sequentially during training and are optimal for candidate classification. Three-fold cross-validation was used to detect performance with the 54 diseased FDG-PET/CT images. The mean sensitivity for detecting primary and metastatic lesions at 3 FPs per case was 0.89 with a 0.10 standard deviation (SD) in the bone region, 0.80 with a 0.10 SD in the lung field, and 0.87 with a 0.10 SD in the neck region. The average areas under the ROC curve were 0.887 with a 0.125 SD for detecting bone metastases, 0.900 with a 0.063 SD for detecting pulmonary lesions, and 0.927 with a 0.035 SD for detecting the neck-mediastinum lesions. These detection performances indicate that the proposed method could be applied clinically. These results also show that the uniform approach has high versatility for providing various lesion detection processes.


Subject(s)
Fluorodeoxyglucose F18 , Positron Emission Tomography Computed Tomography , Image Processing, Computer-Assisted , Positron Emission Tomography Computed Tomography/methods , Positron-Emission Tomography/methods , Radiopharmaceuticals , Sensitivity and Specificity
9.
JA Clin Rep ; 8(1): 11, 2022 Feb 21.
Article in English | MEDLINE | ID: mdl-35190925

ABSTRACT

BACKGROUND: Massive hemoptysis causing inadequate ventilation results in life-threatening consequences. We present a patient who developed respiratory insufficiency produced by bronchiectatic massive hemoptysis and underwent prolonged anticoagulation-free veno-venous extracorporeal membrane oxygenation (VV-ECMO) during which thoracic surgeries were performed. CASE PRESENTATION: A 79-year-old woman suffered massive hemoptysis resulting in respiratory failure during fiberoptic bronchoscopy. Bronchial intubation followed by one lung ventilation failed to ensure adequate oxygenation. Anticoagulation-free VV-ECMO, therefore, was installed immediately. Since conservative hemostatic measures including bronchial arterial embolization were not effective, resection of the culprit lung was performed while on VV-ECMO. Next day an exploratory thoracotomy and intercostal artery embolization were needed for recurrent bleeding. The VV-ECMO was withdrawn after five days of operation. CONCLUSIONS: Massive hemoptysis can be fatal and needs instantaneous and intensive treatments. In our case, long-term anticoagulation-free VV-ECMO during which thoracic surgeries and endovascular interventions were performed provided a favorable outcome.

10.
Health Econ ; 30(6): 1480-1497, 2021 06.
Article in English | MEDLINE | ID: mdl-33819359

ABSTRACT

While increasing attention is given to how health reductions affect workers, estimating their effects is usually challenging. This paper aims to identify the causal effect of health deterioration on labor market outcomes by exploiting the incidence of stroke. Stroke, which often reduces health suddenly and unexpectedly, allows us to exploit the within-person random variation of the timing and isolate the effects of health reduction. By applying the fixed-effects method to a sample of stroke survivors in the University of Michigan Health and Retirement Study data, I find that stroke immediately halves the employment probability as well as hours and weeks worked 1 year after the occurrence and its effects persist for at least 3 years, while earnings reduction is relatively moderate and gradual. I also find the negative effects of stroke are larger among men with severe stroke and women with longer pre-stroke job tenure, while the effects are mitigated for younger women. These results make a stark contrast with the studies on other health events such as cancer diagnosis, which generally find much smaller effects and significant heterogeneity by education and occupation. This analysis shows that the labor market effects largely differ by types of diseases and calls for disease-specific studies in order to understand the social gradient in health and how workers adjust to work limitations.


Subject(s)
Retirement , Stroke , Employment , Female , Humans , Incidence , Male , Occupations , Stroke/epidemiology
11.
Ann Med Surg (Lond) ; 64: 102186, 2021 Apr.
Article in English | MEDLINE | ID: mdl-33747493

ABSTRACT

BACKGROUND: Although indwelling urinary catheters (IUCs) are used intraoperatively and may cause complications (e.g., delirium), only few robust studies have investigated the association between intraoperative IUC use and complications. We hypothesized that IUC use might increase the postoperative incidence of altered mental status and/or urinary catheter infection. MATERIALS AND METHODS: In this retrospective single-center cohort study, we analyzed the data of adult patients undergoing surgery at our facility between January 2013 and December 2018. The primary endpoint was altered mental status and/or incidence of urinary catheter infections. The patients were divided into IUC and control groups. A multivariable logistic regression model was used to identify the predictors of postoperative complications, and a multivariable Cox proportional hazards regression model was used to analyze hospital discharge in unmatched and inverse propensity-weighted patients. RESULTS: Of the 14,284 patients that were reviewed, we analyzed 5112 patients (control group, 44.0%; IUC group, 56.0%). Almost all procedures comprised less invasive surgeries. The prevalence of postoperative altered mental status and postoperative urinary catheter infection were 3.56% and 0.04%, respectively. After inverse propensity weighting, all baseline characteristics were similar between the two groups. However, patients with IUCs had a higher risk of postoperative complications (adjusted odds ratio, 1.97; 95% confidence interval [CI], 1.50-2.59) and prolonged hospital stays (hazard ratio, 0.84; 95% CI, 0.80-0.89). CONCLUSION: In patients undergoing less invasive surgery, IUCs may be associated with a relatively high risk of altered mental status or urinary catheter infection. These data may facilitate preoperative discussions regarding the perioperative use of IUCs.

12.
J Phycol ; 57(2): 416-434, 2021 04.
Article in English | MEDLINE | ID: mdl-33098679

ABSTRACT

The brown alga Scytosiphon lomentaria (Scytosiphonaceae, Ectocarpales) has been reported from cold and warm waters worldwide. Although previous molecular phylogenetic studies and crossing experiments have shown that it is a complex of multiple distinct species, the taxonomic position and accurate distribution of each species have remained largely unclear. For the S. lomentaria complex from Japan, our cox1 and rbcL phylogenetic analyses detected six species. In addition to five previously detected species (species Ia-Va), one species (species VI) was newly found in the subtropical area, Okinawa Island. Species VI was recovered as a sister to species Ia-Va in rbcL. Based on the morphological and phylogenetic data, we concluded that species Ia is S. lomentaria, species IIIa is S. promiscuus, and the other four species are newly described: S. shibazakiorum for species IIa, S. tosaensis for species IVa, S. arcanus for species Va, and S. subtropicus for species VI. The cox1-based analysis also showed that S. lomentaria, S. shibazakiorum, and S. promiscuus have worldwide distributions, while the other three species were not found outside of Japan. In Japan, except for S. subtropicus, distributions of these species overlapped. Our crossing experiments showed that gametic incompatibility (pre-zygotic barrier) was less developed between the allopatric species (i.e., S. subtropicus and others) compared with the sympatric species. It may suggest that pre-zygotic barriers have evolved among the sympatric species due to reinforcement.


Subject(s)
Phaeophyceae , Japan , Phylogeny , Zygote
13.
Respir Med Case Rep ; 31: 101246, 2020.
Article in English | MEDLINE | ID: mdl-33134072

ABSTRACT

OBJECTIVE: In 2014, an autochthonous dengue fever outbreak occurred around the Yoyogi Park in Japan for the first time in 70 years. Despite no local cases reported since then, the risk of another outbreak remains high. This study reviews the autochthonous dengue fever cases of the outbreak, investigates its causes, and delineates preventive measures against autochthonous dengue epidemics. METHODS: We conducted a case series study of 15 patients who visited our institution during the 2014 outbreak. We collected and evaluated data on the surveillance of vector mosquitoes, weather, pest control, travelers' origins and destinations, and imported dengue fever cases using reports made by public institutions. RESULTS: All patients recovered with supportive treatments and none met the diagnostic criteria for severe dengue infection. Twelve patients with positive real-time polymerase chain reactions were confirmed as having dengue virus-1 infections. We found no obvious associations between the number of mosquitoes and the weather, or between the number of imported dengue fever cases and that of travelers. Insect growth regulator (IGR) against vector mosquitoes has been used since 2014 for pest control, but the number of larvae has not declined in the Yoyogi Park, although that of imagoes has been relatively suppressed. CONCLUSION: The 2014 outbreak emerged without particularly favorable climate conditions for vector mosquitoes. We found no obvious associations between the number of travelers or the imported dengue fever cases and the outbreak, but the increasing number of travelers may contribute to another outbreak. Pest control, including IGR, remains essential for infection control.

14.
Ann Transl Med ; 8(7): 438, 2020 Apr.
Article in English | MEDLINE | ID: mdl-32395482

ABSTRACT

BACKGROUND: Benralizumab is a humanized, fucosylated, monoclonal antibody that targets the interleukin 5 (IL-5) α receptor. Several phase III trials have shown that benralizumab can significantly reduce the incidence of acute exacerbations and improve lung function in patients with severe asthma. However, there is a paucity of data from clinical practice. In this prospective study, we evaluated the effectiveness and safety of benralizumab for severe asthma in clinical practice. METHODS: This was a prospective, open-label, single-arm, single-center study in patients with severe asthma in clinical practice (UMIN000031951). Haematological, clinical, functional, and pharmacotherapeutic parameters were evaluated at baseline and at weeks 4 and 12 after initiation of benralizumab. RESULTS: Twenty-six patients were enrolled between May 2018 and March 2019. Both asthma quality of life questionnaire (AQLQ) score and asthma control test (ACT) score showed significant improvement over the study period. Forced expiratory volume in 1.0 second (FEV1) showed a significant increase at week 12 (baseline: 1.57 L; week 12: 1.75 L). Blood eosinophil and basophil counts were significantly decreased at week 12 compared to baseline. At week 12, the dose of regular oral corticosteroids (OCS) was significantly decreased from baseline as was the number of patients on need-based OCS. Benralizumab had no significant effect on fractional exhaled nitric oxide (FeNO) levels and total immunoglobulin E levels. Only one patient experienced mild headache during benralizumab therapy. CONCLUSIONS: In this study, benralizumab conferred clinically significant benefits in patients with severe asthma with no short-term severe adverse events.

15.
J Phycol ; 53(2): 333-341, 2017 04.
Article in English | MEDLINE | ID: mdl-27885652

ABSTRACT

Despite the high number of studies on the fine structure of brown algal cells, only limited information is available on the intercelluar transportation of molecules via plasmodesmata in brown algae. In this study, plasmodesmatal permeability of Halopteris congesta was examined by observing the translocation of microinjected fluorescent tracers of different molecular sizes. The tip region of H. congesta consists of a cylindrical apical cell, while the basal region is multiseriate. Fluorescein isothiocyanate-dextran (FD; 3, 10, and 20 kDa) and recombinant green fluorescent protein (27 kDa) were injected into the apical cell and were observed to diffuse into the neighboring cells. FD of 40 kDa was detected only in the injected apical cell. The plasmodesmatal size exclusion limit was considered to be more than 20 kDa and less than 40 kDa. The extent of translocation of 3 and 10 kDa FD from the apical to neighboring cells 2 h postinjection was estimated based on the fluorescence intensity. It was suggested that the diffusing capacity of plasmodesmata varied according to molecular size. In order to examine acropetal and/or basipetal direction of molecular movement, 3 and 10 kDa FD were injected into the third cell from the apical cell. Successive observations indicated that the diffusion of fluorescence in the acropetal direction took longer than that in the basipetal direction. No ultrastructural difference in plasmodesmata was noted among the cross walls.


Subject(s)
Phaeophyceae/metabolism , Plasmodesmata/metabolism , Biological Transport/genetics , Biological Transport/physiology , Cell Communication/physiology , Dextrans , Fluorescein-5-isothiocyanate/analogs & derivatives , Green Fluorescent Proteins/genetics , Green Fluorescent Proteins/metabolism
16.
Protoplasma ; 254(3): 1341-1351, 2017 May.
Article in English | MEDLINE | ID: mdl-27704277

ABSTRACT

Tissue wounds are mainly caused by herbivory, which is a serious threat for macro-algae, and brown algae are known to regenerate branches or buds in response to wounding. In the present paper, we describe a branch regeneration system, induced by sever damage, in the brown alga Dictyota dichotoma. Segmentations of juvenile thalli induced branch regenerations unless explants possessed apical cells. Apical excisions in distinct positions elucidated that disruption of an apical cell or disconnection of tissue with an apical cell triggered the branch regeneration. Furthermore, spatial positions of regenerated branches seemed to be regulated by the apical region, which was assumed to generate inhibitory effects for lateral branch regeneration. Mechanical incision, which disrupted tissue continuity with the apical region, induced branch regeneration preferentially below the incision. Although we were unable to identify the candidate inhibitory substance, our results suggested that the apical region may have an inhibitory effect on lateral branch regeneration. Additionally, observations of branch regeneration showed that all epidermal cells in D. dichotoma possess the ability to differentiate into apical cells, directly. This may be the first report of algal transdifferentiation during the wound-stress response.


Subject(s)
Cell Differentiation/physiology , Cell Transdifferentiation/physiology , Phaeophyceae/growth & development , Plant Epidermis/cytology , Regeneration/physiology , Phaeophyceae/physiology , Signal Transduction/physiology
17.
Ther Drug Monit ; 38(6): 663-669, 2016 12.
Article in English | MEDLINE | ID: mdl-27661398

ABSTRACT

BACKGROUND: Everolimus has been used for the treatment of unresectable or metastatic renal cell carcinoma (RCC). Here, we measured blood concentrations of everolimus to obtain the population pharmacokinetic parameters and to examine the relationship between blood concentration and clinical outcomes. METHODS: Twenty-two Japanese patients were enrolled. Blood samples were collected before and 2, 4, 8, and 24 hours after drug administration on days 1 and 8 of everolimus therapy (5 or 10 mg) from inpatients; occasional samples were collected from outpatients. Blood concentrations of everolimus were measured by high-performance liquid chromatography with tandem mass spectrometry. Population pharmacokinetic analysis was conducted using the NONMEM software. RESULTS: Everolimus pharmacokinetics was best described by a 2-compartment model with population mean estimates of apparent oral clearance of 10.0 L/h and an interindividual variability of 42.4%. There was no relationship between overall best responses and the predicted trough concentrations at day 8. The predicted trough concentration in patients who terminated everolimus treatment owing to adverse drug reactions (ADRs) was significantly higher than in patients who stopped the treatment owing to disease progression or other reasons (27.6 ± 3.1 versus 15.7 ± 2.3 ng/mL; mean ± SEM). Patients who terminated the treatment owing to ADRs had significantly shorter time-to-treatment failure than other patients (112 versus 187 days, median). CONCLUSIONS: This study reports the first population pharmacokinetic parameters of everolimus in patients with RCC. Individual dose adjustment based on everolimus blood concentrations helps to avoid early drug cessation due to ADRs.


Subject(s)
Antineoplastic Agents/blood , Antineoplastic Agents/pharmacokinetics , Carcinoma, Renal Cell/blood , Everolimus/blood , Everolimus/pharmacokinetics , Kidney Neoplasms/blood , Adult , Aged , Aged, 80 and over , Carcinoma, Renal Cell/drug therapy , Chromatography, High Pressure Liquid/methods , Dose-Response Relationship, Drug , Everolimus/administration & dosage , Female , Humans , Kidney Neoplasms/drug therapy , Male , Middle Aged , Tandem Mass Spectrometry/methods , Young Adult
18.
Eur J Clin Pharmacol ; 72(6): 703-10, 2016 Jun.
Article in English | MEDLINE | ID: mdl-26905999

ABSTRACT

PURPOSE: Docetaxel is frequently used in the treatment of a wide variety of solid tumors, including breast cancer. The aim of this study is to obtain the population pharmacokinetic parameters of docetaxel in Japanese female patients with breast cancer. METHODS: Blood samples from 24 patients were collected sequentially before and after docetaxel infusion. Genomic DNA was isolated from the peripheral blood and genotyped for the selected polymorphisms in the candidate genes of drug transporters and metabolizing enzymes. The influence of patient characteristics on the pharmacokinetics of docetaxel was evaluated using the nonlinear-mixed-effect modeling program, NONMEM. As a basis for comparison, the pharmacokinetics of another taxane paclitaxel in 41 separate female patients with breast cancer was calculated. RESULTS: A two-compartment model adequately described the pharmacokinetic profiles of docetaxel. The population mean estimates of the total body clearance for patients aged 58 years or less and the central volume of distribution for docetaxel were 32.6 L/h and 5.77 L, respectively. In patients over 58 years, the clearance was 24 % higher than that in the younger patients. No influences of the genotypes examined were noted on the clearance of docetaxel. The clearance of paclitaxel was not affected by patient age. CONCLUSIONS: Patients over the age of 58 years showed significantly higher clearance of docetaxel than that in patients aged 58 years or less. Since the clearance of paclitaxel was not affected by the age, it is possible that the pharmacokinetic mechanisms of docetaxel might be specifically affected by age in females.


Subject(s)
Aging/physiology , Antineoplastic Agents, Phytogenic/pharmacokinetics , Breast Neoplasms/metabolism , Models, Biological , Taxoids/pharmacokinetics , Adult , Aged , Antineoplastic Agents, Phytogenic/blood , Antineoplastic Agents, Phytogenic/therapeutic use , Asian People , Breast Neoplasms/drug therapy , Docetaxel , Female , Humans , Middle Aged , Taxoids/blood , Taxoids/therapeutic use
19.
J Stroke Cerebrovasc Dis ; 25(1): 57-62, 2016 Jan.
Article in English | MEDLINE | ID: mdl-26409716

ABSTRACT

BACKGROUND: Malnutrition affects the activities of daily living (ADLs) in convalescent patients with cerebrovascular disorders. We investigated the relationship between nutritional improvement, energy intake at admission, and recovery of ADLs. METHODS: We evaluated 67 patients with cerebrovascular disorders admitted to our rehabilitation hospital between April 2013 and April 2015. These patients received interventions from the rehabilitation nutritional support team according to the following criteria: weight loss of 2 kg or more and body mass index of 19 kg/m(2) or lower. Exclusion criteria included a body mass index of 25 kg/m(2) or higher, duration of intervention of less than 14 days, or transfer to an acute care hospital because of clinical deterioration. We assessed nutritional status using the Geriatric Nutritional Risk Index (GNRI) and ADL using the Functional Independence Measure (FIM) score, FIM gain, and FIM efficiency. RESULTS: The mean age of the patients was 78.7 ± 8.0 years. The numbers of patients in each category of cerebrovascular disorder were 39 with cerebral infarction, 16 with intracerebral hemorrhage, 8 with subarachnoid hemorrhage, and 4 others. Compared with the counterpart group, the group with an improvement in GNRI had a greater gain in FIM (median 17 and 20, respectively; P = .036) and a higher FIM efficiency (.14 and .22, respectively; P = .020). Multivariate stepwise regression analysis showed that an improvement in GNRI, increasing energy intake at admission, and intracerebral hemorrhage were associated independently with greater FIM efficiency. CONCLUSIONS: This study suggested that nutritional improvement and energy intake at admission are associated with recovery of ADL after cerebrovascular disorders.


Subject(s)
Cerebrovascular Disorders/rehabilitation , Energy Intake , Malnutrition/prevention & control , Nutritional Status , Activities of Daily Living , Aged , Aged, 80 and over , Body Mass Index , Cerebrovascular Disorders/complications , Cerebrovascular Disorders/physiopathology , Cross-Sectional Studies , Female , Humans , Japan/epidemiology , Male , Malnutrition/complications , Nutritional Support , Recovery of Function , Rehabilitation Centers , Retrospective Studies , Thinness/epidemiology , Weight Loss
20.
Protist ; 166(5): 506-21, 2015 Nov.
Article in English | MEDLINE | ID: mdl-26386358

ABSTRACT

The marine pennate diatom Phaeodactylum tricornutum has become a model for diatom biology, due to its ease of culture and accessibility to reverse genetics approaches. While several features underlying the molecular mechanisms of cell division have been described, morphological analyses are less advanced than they are in other diatoms. We therefore examined cell ultrastructure changes prior to and during cytokinesis. Following chloroplast division, cleavage furrows are formed at both longitudinal ends of the cell and are accompanied by significant vesicle transport. Although neither spindle nor microtubules were observed, the nucleus appeared to be split by the furrow after duplication of the Golgi apparatus. Finally, centripetal cytokinesis was completed by fusion of the furrows. Additionally, F-actin formed a ring structure and its diameter became smaller, accompanying the ingrowing furrows. To further analyse vesicular transport during cytokinesis, we generated transgenic cells expressing yellow fluorescent protein (YFP) fusions with putative diatom orthologs of small GTPase Sec4 and t-SNARE protein SyntaxinA. Time-lapse observations revealed that SyntaxinA-YFP localization expands from both cell tips toward the center, whereas Sec4-YFP was found in the Golgi and subsequently relocalizes to the future division plane. This work provides fundamental new information about cell replication processes in P. tricornutum.


Subject(s)
Algal Proteins/metabolism , Cytokinesis , Diatoms/physiology , Diatoms/ultrastructure , Cell Membrane/metabolism , Cell Membrane/ultrastructure , Diatoms/cytology , Diatoms/metabolism , Microscopy, Electron, Transmission , Organisms, Genetically Modified/physiology , Protein Transport
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