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1.
Small ; 18(51): e2205306, 2022 Dec.
Article in English | MEDLINE | ID: mdl-36328712

ABSTRACT

Recently, perovskite (PV) oxides with ABO3 structures have attracted considerable interest from scientists owing to their functionality. In this study, CaFeOx is introduced to reveal the resistive switching properties and mechanism of oxygen vacancy transition in PV and brownmillerite (BM) structures. BM-CaFeO2.5 is grown on an Nb-STO conductive substrate epitaxially. CaFeOx exhibits excellent endurance and reliability. In addition, the CaFeOx also demonstrates an electroforming-free characteristic and multilevel resistance properties. To construct the switching mechanism, high-resolution transmission electron microscopy is used to observe the topotactic phase change in CaFeOx . In addition, scanning TEM and electron energy loss spectroscopy show the structural evolution and valence state variation of CaFeOx after the switching behavior. This study not only reveals the switching mechanism of CaFeOx , but also provides a PV oxide option for the dielectric material in resistive random-access memory (RRAM) devices.

2.
Behav Sci (Basel) ; 12(7)2022 Jul 12.
Article in English | MEDLINE | ID: mdl-35877297

ABSTRACT

Encouraging feedback positively affects learners' self-efficacy; in language learning, self-efficacy predicts language learner performance and behavior. Our research involved three studies to expand knowledge about why and how we can enhance English as a Foreign Language (EFL) learners' self-efficacy beliefs in online settings. In Study 1, based on an online survey with 310 participants, we ascertained the extent to which EFL learners with greater self-efficacy tend to challenge themselves by learning content that requires a proficiency level that is higher than their current proficiency. In Study 2, we recruited 120 EFL learners; the results indicate that positive feedback via emojis embedded in online courses could significantly boost EFL learners' self-efficacy beliefs about learning English. Study 3 involved 35 participants and extended the understanding provided by the first two studies, showing that EFL learners not only like to use emojis for computer-mediated communication (CMC), but also prefer to receive them as feedback. This research adds to knowledge on "why" and "how" we can enhance EFL learners' self-efficacy beliefs in online contexts. We systematically provide empirical evidence regarding the aforementioned issues and demonstrate that positive feedback through emojis has great potential to enhance EFL learners' self-efficacy, even when such feedback is subliminal.

3.
Materials (Basel) ; 15(11)2022 May 24.
Article in English | MEDLINE | ID: mdl-35683047

ABSTRACT

This study aims to provide a system to recycle vanadium resources and recover membranes from waste proton-exchange membranes. This research is divided into two parts. To begin, ion exchange batch and column experiments were applied to adsorb vanadium in a membrane. In this process, the waste membrane was initially dissolved in a 50% ethanol solution, and the suspension obtained by dispersing the membrane had 74 mg/L of vanadium. Then, Dowex G26 resin was used to adsorb vanadium from the membrane dispersion in the ion-exchange process. The adsorptive behavior and optimal parameters were explored in this study. The vanadium ions were then eluted by HCl to obtain an enrichment solution, and the V2O5 was received through precipitation and calcination methods. After obtaining the vanadium-free dispersion, the recycled membrane was prepared by recasting it in the second part. The characteristics of the recycled membrane, such as the moisture, FTIR spectra, ion-exchange capacity, and ion conductivity, are discussed. The results revealed that the adsorption capacity of vanadium through Dowex G26 was 81.86 mg/g. The eluting efficiency of HCl was 97.5%, and the optimal parameters of the precipitation and calcination processes were set as pH 5, NH4Cl:V = 2:1, and 350 °C. The moisture of the recycled membrane was 25.98%, and the IEC was 0.565 meq/g. The consequences of FTIR and ion conductivity demonstrated that the vanadium in the recycled membrane was eliminated by the ion-exchange method; however, the microstructure of the recycled membrane was influenced during ion exchange and recasting.

4.
Pharmacogenet Genomics ; 32(1): 31-38, 2022 01 01.
Article in English | MEDLINE | ID: mdl-34380995

ABSTRACT

OBJECTIVES: Opioid dependence is currently one of the most serious problems affecting the social norms and public health system. Methadone maintenance therapy (MMT) is being widely used in treating heroin-dependent patients. The mechanism of methadone metabolism and disposition has been shown to involve cytochrome P450 (CYP450) and P-glycoprotein. The aim of this study was to explore the relationships among genetic polymorphisms, BMI and effective dose of methadone used in MMT within a northern Taiwan cohort. METHODS: One hundred heroin-dependent patients were enrolled in the study. The clinical data gathered included methadone dose, sex and BMI. DNA was collected from the oral swab of the participants to analyze the relevant alleles. RESULTS: An effective methadone dose correlated with sex, BMI and the presence of ABCB1 2677GG (rs2032582) and CYP2B6 516GG (rs374527). Furthermore, the CYP2B6 516GG homozygote was related to a higher average dose of methadone (GG: 68.50 ± 32.43; GT: 52.28 ± 25.75; TT: 44.44 ± 29.64; P < 0.02), whereas the ABCB1 2677GG homozygote was related to a lower dose (GG: 51.09 ± 20.83; GT: 69.65 ± 37.51; TT: 62.52 ± 30.44; P < 0.05). We examined the predictive effect of polymorphisms combined with sex and BMI on methadone dose by conducting multiple linear regressions. Our data predicted the average dose of methadone in approximately 30% of heroin-dependent patients. CONCLUSION: The interactions between genetic polymorphisms and clinical features proved useful in identifying the effective dose of MMT for heroin-dependent patients in Taiwan more precisely.


Subject(s)
Heroin Dependence , Pharmaceutical Preparations , Heroin Dependence/drug therapy , Heroin Dependence/genetics , Humans , Methadone , Pharmacogenomic Testing , Polymorphism, Single Nucleotide/genetics , Treatment Outcome
5.
Br J Psychol ; 112(4): 866-878, 2021 Nov.
Article in English | MEDLINE | ID: mdl-33615446

ABSTRACT

Social distance regulations have been widely adopted during the global COVID-19 pandemic. From an evolutionary perspective, social connection and money are interchangeable subsistence resources for human survival. The substitutability principle of human motivation posits that scarcity in one domain (e.g., social connection) could motivate people to acquire or maintain resources in another domain (e.g., money). Two experiments were conducted to test the possibility that COVID-19 social distancing enhances the desire for money. Results showed that compared with controls, participants receiving social distancing primes (via recollection of experiences of social distancing or a Chinese glossary-search task) offered less money in the dictator game, showed lower willingness towards charitable donation (Experiment 1; N = 102), donated less money to a student fund, and rated money as having more importance (Experiment 2; N = 140). Our findings have far-reaching implications for financial decisions, charitable donations, and prosociality during and after the COVID-19 pandemic.


Subject(s)
COVID-19 , Pandemics , Humans , Motivation , Physical Distancing , SARS-CoV-2
6.
Medicine (Baltimore) ; 99(22): e20476, 2020 May 29.
Article in English | MEDLINE | ID: mdl-32481457

ABSTRACT

To investigate the healthcare expenditures and length of stay (LOS) of sepsis-related hospitalizations in Taiwan.This is a retrospective claim database study. Data were obtained from the two-million-sample longitudinal health and welfare database (LHWD). Adult patients hospitalized with sepsis between 2010 and 2014 were identified by International Classification of Diseases 9th Edition Clinical Modification (ICD-9-CM) codes, and these patients were divided into three levels of sepsis severity. The amount and distribution of their total medical expenditures were investigated.In total, 62,517 patients with 97,790 sepsis-related hospitalizations were included in the present study. It was found that ward fees and medicines comprised the largest component of expenses for sepsis-related hospitalizations. In addition, our study results indicated that the median sepsis-related hospitalization cost was 66.4 thousand New Taiwan Dollar (NT dollars) in 2014, and a significant temporal change was found between 2010 and 2014. The median LOS in a hospital and in an intensive care unit were 11 and 7 days, respectively. Both expenditures and LOS were found to increase with sepsis severity.This study provides an updated and better understanding of the costs and LOS of sepsis-related hospitalizations in Taiwan. It was found that ward fees and medicine fees were the major components of hospital costs.


Subject(s)
Hospitalization/economics , Sepsis/economics , Critical Care/economics , Health Expenditures/statistics & numerical data , Hospital Costs/statistics & numerical data , Humans , Length of Stay/economics , Longitudinal Studies , Retrospective Studies , Severity of Illness Index , Taiwan
7.
Medicine (Baltimore) ; 98(20): e15725, 2019 May.
Article in English | MEDLINE | ID: mdl-31096527

ABSTRACT

To investigate the epidemiology trend and characteristics of sepsis-related hospitalizations in Taiwan, and to compare the differences among different severity levels of sepsis.This study is a retrospective national claim database analysis. Hospitalized adult patients with sepsis between 2010 and 2014 were identified from the Two-Million-Sample Longitudinal Health and Welfare Database (LHWD) by the International Classification of Diseases 9th Edition Clinical Modification (ICD-9-CM). The patients were divided into 3 severity groups based on their medical records during hospitalization.The study results showed that in Taiwan, there were 643 new cases of sepsis in 100,000 Taiwanese. The mortality of all septic patients in Taiwan was 287 per 100,000 people, and the case fatality was 29.2%. It was found that the mortality and incidence of sepsis in Taiwan have increased year by year, but there has been no significant change over time. In addition, demographic variation exists in the epidemiology of sepsis. In all the rates investigated, the men's were higher than the women's and the elderly's were higher than the youths'. The analysis results also showed that the respiratory system was the most common site of organ failure in septic patients.The incidence and mortality of any severity level of sepsis were 643, and 287 per 100,000 people in Taiwan, respectively, and the average case fatality was 29.2% during the study period (2010-2014). The respiratory system was the major infected site and site of organ dysfunction, especially in the more severe levels.


Subject(s)
Respiratory Insufficiency/epidemiology , Sepsis/epidemiology , Adolescent , Adult , Aged , Female , Hospitalization/statistics & numerical data , Humans , Incidence , Male , Medical Records , Mortality , Respiratory Insufficiency/mortality , Retrospective Studies , Sepsis/mortality , Severity of Illness Index , Taiwan/epidemiology
8.
Int J Pediatr Otorhinolaryngol ; 121: 157-163, 2019 Jun.
Article in English | MEDLINE | ID: mdl-30913504

ABSTRACT

OBJECTIVE: Cisplatin is a chemotherapeutic drug known to induce hearing loss. Although corticosteroids may help to mitigate the ototoxic side effects of cisplatin, there are complications associated with their systemic and prolonged use. The goal of this study is to test the efficacy of extended-release fluticasone propionate intracochlear implant particles to protect against cisplatin-induced hearing loss. METHODS: We used guinea pigs (n = 9) injected with cisplatin (IP, 12 mg/kg weight). Fluticasone particles were delivered to the cochlear scala tympani through the round window membrane into the right ears of the guinea pigs (left ears being used as a control) two weeks prior to cisplatin administration, and hearing function was evaluated by ABR and DPOAE before implantation, immediately before cisplatin administration, and 2 weeks after the challenge with cisplatin. Data was statistically evaluated using paired t-test analysis. RESULTS: No significant differences were observed in ABR threshold between control and implanted ears on day 14 (23.9 ±â€¯2.3 dB vs. 25.6 ±â€¯1.3 dB, P = 0.524), whereas the significant cisplatin-induced hearing loss in control animals (23.9 ±â€¯2.3 dB at day 14 vs. 40.7 ±â€¯2.5 dB at day 28, P ≤ 0.0001) was prevented in implanted animals (25.6 ±â€¯1.3 dB at day 14 vs. 25.0 ±â€¯3.1 at day 28, P ≥ 0.85). A similar, though not statistically significant, trend was observed in DPOAE responses in untreated ears (7.9 ±â€¯5.8 dB at day14 vs. -0.5 ±â€¯5.3 dB at day 28, P = 0.654) as compared to treatment (11.1 ±â€¯3.4 dB at day 14 vs. 13.6 ±â€¯4.8 dB at day 28, P = 0.733). CONCLUSION: These results suggest that fluticasone intracochlear implants are safe and able to provide effective otoprotection against cisplatin-induced hearing loss in the guinea pig model.


Subject(s)
Anti-Inflammatory Agents/therapeutic use , Antineoplastic Agents/adverse effects , Cisplatin/adverse effects , Fluticasone/therapeutic use , Hearing Loss/chemically induced , Hearing Loss/prevention & control , Animals , Anti-Inflammatory Agents/administration & dosage , Auditory Threshold , Delayed-Action Preparations , Drug Implants , Evoked Potentials, Auditory, Brain Stem , Fluticasone/administration & dosage , Guinea Pigs , Hearing , Hearing Loss/physiopathology , Otoacoustic Emissions, Spontaneous , Scala Tympani
9.
Antioxid Redox Signal ; 31(2): 109-126, 2019 07 10.
Article in English | MEDLINE | ID: mdl-30417658

ABSTRACT

Aims: The coordination of neurons to execute brain functions requires plenty of oxygen. Thus, it is not surprising that the chronic hypoxia resulting from chronic obstructive pulmonary diseases (COPD) can cause neuronal damage. Injury in the cortex can give rise to anxiety and cognitive dysfunction. This study investigated what causes hypoxia-induced neuronal injury and what strategies might be used to protect neurons against such damage. Results: This study found that hypoxia in primary cortical neurons caused neurite retraction, a caspase-6-dependent process. The hypoxic stress activated caspase-6 within the neurite, leading to microtubule disassembly and neurite retraction. The effect of hypoxia on caspase-6 activation, microtubule disassembly, and neurite retraction was alleviated by nitrite treatment. The protective role of nitrite was further supported by the observation that the active-site Cys146 of caspase-6 was S-nitrosylated in hypoxic neuro-2a cells treated with nitrite. We further validated the beneficial effect of nitrite on neuronal function against hypoxic stress in vivo. Using the wild-type or Apo E-/- mice exposed to chronic hypoxia as a model, we demonstrated that supplementing drinking water with nitrite suppressed active caspase-6 in the cortex of the brain, concomitant with the prevention of hypoxia-induced anxiety in the animals. Innovation: These results are the first evidence of a new pathway for the activation of caspase-6 and the first to indicate that nitrite can protect neurons against chronic hypoxic insult. Conclusion: Our findings suggest that nitrite holds great potential for the treatment of diseases such as COPD associated with hypoxia-induced neuronal injury.


Subject(s)
Caspase 6/metabolism , Hypoxia, Brain/prevention & control , Neuroprotective Agents/administration & dosage , Nitrites/administration & dosage , Animals , Caspase 6/chemistry , Catalytic Domain , Cell Line , Disease Models, Animal , Hypoxia, Brain/metabolism , Mice , Mice, Knockout, ApoE , Neurites/drug effects , Neurites/metabolism , Neurons/drug effects , Neurons/metabolism , Neuroprotective Agents/pharmacology , Nitrites/pharmacology
10.
Otol Neurotol ; 39(9): 1195-1202, 2018 10.
Article in English | MEDLINE | ID: mdl-30199502

ABSTRACT

OBJECTIVE: Investigate a new polymer-based drug coating suitability for safe intracochlear delivery and ability to maintain long-term physiologically active levels of the corticosteroid fluticasone propionate. STUDY DESIGN: In vitro dissolution study to evaluate release profiles of polymer-coated drug particles and in vivo studies using a guinea pig model to measure perilymph drug concentrations at specific time points after implantation with polymer-coated drug particles and evaluate their effect on hearing function. METHODS: Polymer-coated fluticasone propionate (FP) particles were surgically implanted in guinea pigs through the round window membrane into the cochlear scala tympani. In the pilot study, pre- and post-op hearing thresholds were conducted on days 7, 14, and 42. In a second study, post-op hearing thresholds were conducted on days 90, 120, and 180. Perilymph drug concentrations were measured on the same time points. RESULTS: In 15 of 16 animals from day 7 through day 90, drug levels were within the targeted range, with no initial burst release detected. Drug was present in all animals on day 90 and was detected in some animals at 120 and 180 days. Hearing was tested and compared with non-implanted ears. Very good hearing preservation was observed in ears implanted with intracochlear particles when compared with contralateral ears. CONCLUSIONS: The polymer-based extended release system is effective in providing long-term, stable drug delivery for at least 90 days with good hearing outcomes. The results of this study support the potential for achieving long-term drug delivery with a single intracochlear administration.


Subject(s)
Anti-Inflammatory Agents/administration & dosage , Anti-Inflammatory Agents/pharmacokinetics , Cochlea/drug effects , Drug Delivery Systems/methods , Fluticasone/administration & dosage , Fluticasone/pharmacokinetics , Animals , Delayed-Action Preparations , Guinea Pigs , Hearing/drug effects , Perilymph/chemistry , Perilymph/drug effects , Pilot Projects , Polymers
11.
J Food Drug Anal ; 25(4): 819-827, 2017 Oct.
Article in English | MEDLINE | ID: mdl-28987358

ABSTRACT

In recent years, the use of fermented plant products to protect against various metabolic syndromes has been increasing enormously. The objective of this study was to check the regulatory efficacy of fermented plant extract (FPE) on intestinal microflora, lipid profile, and antioxidant status in mildly hypercholesterolemic volunteers. Forty-four mildly hypercholesterolemic individuals (cholesterol 180-220 mg/dL) were recruited and assigned to two groups: experimental or placebo. Volunteers were requested to drink either 60 mL of FPE or placebo for 8 weeks. Anthropometric measurements were done in the initial, 4th, 8th, and 10th weeks. The anthropometric parameters such as body weight, body fat, and body mass index were markedly lowered (p<0.05) on FPE intervention participants. Moreover, the total antioxidant capacity and total phenolics in plasma were considerably increased along with a reduction (p<0.05) in total cholesterol (TC) and low-density lipoprotein cholesterol (LDL-c) after FPE supplementation. Participants who drank FPE showed a pronounced increase (p<0.05) in the number of beneficial bacteria such as Bifidobacterium spp. and Lactobacillus spp., whereas the number of harmful bacteria such as Escherichia coli and Clostridium perfringens (p<0.05) were concomitantly reduced. Furthermore, the lag time of LDL oxidation was substantially ameliorated in FPE-administered group, thus indicating its antioxidative and cardioprotective properties. Treatment with FPE substantially improved the intestinal microflora and thereby positively regulated various physiological functions by lowering the anthropometric parameters, TC, and LDL-c, and remarkably elevated the antioxidant capacity and lag time of LDL oxidation. Therefore, we recommended FPE beverage for combating hypercholesterolemia.


Subject(s)
Bacteria/isolation & purification , Gastrointestinal Microbiome , Hypercholesterolemia/microbiology , Intestines/microbiology , Lipids/chemistry , Plant Extracts/administration & dosage , Adult , Anticholesteremic Agents/administration & dosage , Anticholesteremic Agents/chemistry , Bacteria/classification , Bacteria/genetics , Bacteria/metabolism , Female , Fermentation , Humans , Hypercholesterolemia/metabolism , Intestinal Mucosa/metabolism , Male , Middle Aged , Plant Extracts/chemistry , Plant Extracts/metabolism
12.
Environ Monit Assess ; 187(1): 4109, 2015 Jan.
Article in English | MEDLINE | ID: mdl-25404540

ABSTRACT

The objective of this work tends to promote methane content in biogas and evaluate sulfur dioxide emission from direct biogas combustion without desulfurization. Analytical results of biogas combustion showed that combustion of un-desulfurized biogas exhausted more than 92% of SO2 (P < 0.01). In the meantime, more than 90% of hydrogen sulfide was removed during the combustion process using un-desulfurized biogas (P < 0.01). Those disappeared hydrogen sulfide may deposit on the surfaces of power generator's engines or burner heads of boilers. Some of them (4.6-9.1% of H2S) were converted to SO2 in exhaust gas. Considering the impacts to human health and living environment, it is better to desulfurize biogas before any applications.


Subject(s)
Air Pollutants/analysis , Animal Husbandry/methods , Biofuels , Environmental Monitoring , Sulfur Dioxide/analysis , Animals , Hydrogen Sulfide/analysis , Methane/analysis , Swine , Taiwan
13.
Toxicol Appl Pharmacol ; 259(2): 219-26, 2012 Mar 01.
Article in English | MEDLINE | ID: mdl-22245593

ABSTRACT

2-(3-Methoxyphenyl)-5-methyl-1,8-naphthyridin-4(1H)-one (HKL-1), a 2-phenyl-1,8-naphthyridin-4-one (2-PN) derivative, was synthesized and evaluated as an effective antimitotic agent in our laboratory. However, the molecular mechanisms are uncertain. In this study, HKL-1 was demonstrated to induce multipolar spindles, sustain mitotic arrest and generate multinucleated cells, all of which indicate mitotic catastrophe, in human leukemia HL-60 cells. Western blotting showed that HKL-1 induces mitotic catastrophe in HL-60 cells through regulating mitotic phase-specific kinases (down-regulating CDK1, cyclin B1, CENP-E, and aurora B) and regulating the expression of Bcl-2 family proteins (down-regulating Bcl-2 and up-regulating Bax and Bak), followed by caspase-9/-3 cleavage. These findings suggest that HKL-1 appears to exert its cytotoxicity toward HL-60 cells in culture by inducing mitotic catastrophe.


Subject(s)
Antineoplastic Agents/pharmacology , Cell Cycle Checkpoints/drug effects , Leukemia/drug therapy , Microtubules/metabolism , Mitosis/drug effects , Naphthyridines/pharmacology , Aurora Kinase B , Aurora Kinases , CDC2 Protein Kinase/antagonists & inhibitors , CDC2 Protein Kinase/metabolism , Caspases/metabolism , Cell Cycle Checkpoints/physiology , Cell Survival/drug effects , Chromosomal Proteins, Non-Histone/antagonists & inhibitors , Chromosomal Proteins, Non-Histone/metabolism , Cyclin B1/antagonists & inhibitors , Cyclin B1/metabolism , Flow Cytometry , HL-60 Cells , Humans , Inhibitory Concentration 50 , Leukemia/metabolism , Leukemia/pathology , Mitosis/physiology , Protein Serine-Threonine Kinases/antagonists & inhibitors , Protein Serine-Threonine Kinases/metabolism , Proto-Oncogene Proteins c-bcl-2/metabolism
14.
J Clin Ultrasound ; 39(4): 240-2, 2011 May.
Article in English | MEDLINE | ID: mdl-21480292

ABSTRACT

The sonographic presentation of intramedullary bone tumors is rarely reported. A patient with right shoulder pain for 7 months was clinically diagnosed with shoulder impingement syndrome. Sonographic examination revealed a segment of thinning cortex with a large, heteroechoic tumor deep in the greater tuberosity of the humerus. Increased peripheral vascularity of the tumor was observed in the power Doppler mode. The definite diagnosis was a giant cell tumor, whose sonographic findings are discussed.


Subject(s)
Giant Cell Tumor of Bone/diagnostic imaging , Humerus/diagnostic imaging , Adult , Biopsy , Diagnosis, Differential , Giant Cell Tumor of Bone/pathology , Humans , Humerus/pathology , Magnetic Resonance Imaging , Male , Ultrasonography, Doppler
15.
Histochem Cell Biol ; 135(4): 361-73, 2011 Apr.
Article in English | MEDLINE | ID: mdl-21437620

ABSTRACT

Pinin (pnn) is an SR-related protein that is ubiquitously expressed in most cell types and functions in regulating pre-mRNA splicing and mRNA export. Previously, we demonstrated that pnn is expressed in all tissues during mouse embryonic development with highest levels of expression in the central nervous system (CNS). Here we show that pnn and other SR proteins including SC35 are differentially expressed in the adult mouse CNS, displaying cell type-specific distribution patterns. Immunohistochemical analysis of whole-brain sections showed that levels of pnn and SR proteins expression were very low or nonexistent in the corpus callosum and white matter of cerebellum and spinal cord. Double-immunostaining with antibodies specific to neuron or glial cells showed that most astrocytes and microglia expressed neither pnn nor SR proteins. In contrast, oligodendrocytes and neurons expressed moderate and high levels, respectively, of both pnn and SR proteins. These results suggest that astrocytes are unique among cell types of neuroblast origin in terms of expression SR family proteins. Our results pave the way for future studies of the functional roles of pnn and SR family proteins in adults.


Subject(s)
Central Nervous System/metabolism , RNA-Binding Proteins/metabolism , Animals , Cell Adhesion Molecules , Cell Differentiation , Central Nervous System/chemistry , Central Nervous System/cytology , DNA-Binding Proteins , Immunohistochemistry , In Situ Hybridization , Mice , Nuclear Proteins , RNA Splicing , RNA, Messenger/analysis , RNA-Binding Proteins/analysis , RNA-Binding Proteins/genetics
16.
J Cell Biochem ; 109(6): 1274-85, 2010 Apr 15.
Article in English | MEDLINE | ID: mdl-20186884

ABSTRACT

Centrosomal protein 55 (Cep55), located in the centrosome in interphase cells and recruited to the midbody during cytokinesis, is essential for completion of cell abscission. Northern blot previously showed that a high level of Cep55 is predominantly expressed in the testis. In the present study, we examined the spatial and temporal expression patterns of Cep55 during mouse testis maturation. We found that Cep55, together with pericentrin, another centrosomal protein, were localized to the intercellular bridges (IBs) interconnecting spermatogenic cells in a syncytium. The IBs were elaborated as a double ring structure formed by an inner ring decorated by Cep55 or pericentrin and an outer ring of mitotic kinesin-like protein 1 (MKLP1) in the male germ cell in early postnatal stages and adulthood. In addition, Cep55 and pericentrin were also localized to the acrosome region and flagellum neck and middle piece in elongated spermatids, respectively. These results suggest that Cep55 and pericentrin are required for the stable bridge between germ cells during spermatogenesis and spermiogenesis.


Subject(s)
Antigens/metabolism , Nuclear Proteins/metabolism , Testis/metabolism , Animals , Blotting, Northern , Blotting, Western , Cell Cycle Proteins/metabolism , Cell Line, Tumor , HeLa Cells , Hep G2 Cells , Humans , Immunohistochemistry , Male , Mice , Mice, Inbred BALB C , Microscopy, Fluorescence , Microtubule-Associated Proteins/metabolism
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