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1.
J Helminthol ; 94: e145, 2020 Apr 14.
Article in English | MEDLINE | ID: mdl-32284088

ABSTRACT

Epidemiological studies of Echinococcus multilocularis infections in definitive hosts require a reliable and economic diagnostic method. In this study, the current copro-DNA examination technique was modified by increasing the faecal amounts tested and adding a step to neutralize the faeces before DNA extraction. Reliability of the modified method was evaluated using rectal faecal samples from red foxes and comparing them with intestinal worms detected using the sedimentation and counting technique (SCT) following necropsy. The modified copro-DNA examination method demonstrated 93.9% sensitivity (138/147) on the SCT. Its detectability increased depending on the worm burden, and the sensitivity was 100% in cases harbouring over 1000 worms. From 111 SCT-negative cases, six (5.4%) were copro-DNA-positive, and all were confirmed as E. multilocularis via sequencing analysis. Five of the remaining 105 SCT-negative cases (4.8%) retained polymerase chain reaction (PCR) inhibitors in the extracted solution, suggesting that approximately 5% of the red fox faeces retained these inhibitors after treatment with the present copro-DNA extraction method. Although further evaluation is needed for faeces deposited in the wild, the present copro-DNA examination technique will help monitor the E. multilocularis prevalence in definitive hosts. When used for detailed evaluations of endemicity (e.g. changes in infection pressure or spread in non-endemic areas), the absence of PCR inhibitors should be confirmed, and multiple trials on faecal subsamples are recommended.


Subject(s)
DNA, Helminth/isolation & purification , Echinococcosis/veterinary , Feces/parasitology , Foxes/parasitology , Animals , Echinococcosis/epidemiology , Echinococcus multilocularis , Feces/chemistry , Prevalence , Reproducibility of Results , Sensitivity and Specificity
2.
Br J Dermatol ; 180(4): 869-880, 2019 04.
Article in English | MEDLINE | ID: mdl-30339739

ABSTRACT

BACKGROUND: The skin is the first organ that manifests changes in response to zinc deficiency. However, the molecular mechanism underlying how zinc is involved in skin homeostasis, especially its epigenetic regulation, is largely unknown. OBJECTIVES: In this study we demonstrate the importance of zinc levels and the zinc transporter ZIP10 in the epigenetic maintenance of human epidermal homeostasis. METHODS: Adult human skin, including skin appendages, were stained with anti-ZIP10 antibody. Histone acetyltransferase (HAT) activity was assessed after treating human keratinocytes with ZIP10 small interfering (si)RNAs or the zinc chelator TPEN. ZIP10- or HAT-regulated genes were analysed based on limma bioinformatics analysis for keratinocytes treated with ZIP10 siRNAs or a HAT inhibitor, or using a public database for transcription factors. A reconstituted human skin model was used to validate the role of ZIP10 in epidermal differentiation and the functional association between ZIP10 and HAT. RESULTS: ZIP10 is predominantly expressed in the interfollicular epidermis, epidermal appendages and hair follicles. ZIP10 depletion resulted in epidermal malformations in a reconstituted human skin model via downregulation of the activity of the epigenetic enzyme HAT. This decreased HAT activity, resulting from either ZIP10 depletion or treatment with the zinc chelator TPEN, was readily restored by zinc supplementation. Through bioinformatics analysis for gene sets regulated by knockdown of SLC39A10 (encoding ZIP10) and HAT inhibition, we demonstrated that ZIP10 and HATs were closely linked with the regulation of genes related to epidermal homeostasis, particularly filaggrin and metallothionein. CONCLUSIONS: Our study suggests that ZIP10-mediated zinc distribution is crucial for epidermal homeostasis via HATs. Therefore, zinc-dependent epigenetic regulation could provide alternatives to maintaining healthy skin or alleviating disorders with skin barrier defects.


Subject(s)
Cation Transport Proteins/metabolism , Epidermis/enzymology , Epigenesis, Genetic/physiology , Histone Acetyltransferases/metabolism , Zinc/deficiency , Adult , Benzoates/pharmacology , Cation Transport Proteins/genetics , Cell Differentiation/drug effects , Cell Differentiation/genetics , Cell Line , Chelating Agents/pharmacology , Down-Regulation , Epidermis/drug effects , Epigenesis, Genetic/drug effects , Ethylenediamines/pharmacology , Filaggrin Proteins , Gene Knockdown Techniques , Histone Acetyltransferases/antagonists & inhibitors , Histone Acetyltransferases/genetics , Humans , Hydroxamic Acids , Keratinocytes , Nitrobenzenes , Primary Cell Culture , Pyrazoles/pharmacology , Pyrazolones , RNA, Small Interfering/metabolism , Zinc/administration & dosage , Zinc/metabolism
3.
J Helminthol ; 90(6): 766-772, 2016 Nov.
Article in English | MEDLINE | ID: mdl-26750177

ABSTRACT

Experimental Echinococcus multilocularis infection and deworming was repeated three or five times in nine dogs at various re-infection schedules. The mean number of worms decreased more than 91% in dogs with repeated infection, compared to first infection controls (n= 6). The copro-antigen assay and the egg count in the faeces suggested that the worm burden gradually decreased each time the dogs were re-infected. To examine whether such worm exclusion was a non-specific response, five dogs were sequentially infected with the parasite four times and subsequently fed freely for 6 months. Even after the 6-month interval, the five dogs that were infected five times with the parasite were still able largely to exclude the adult worms. The results suggested that the ability of worm exclusion in dogs that developed a resistance did not become rapidly extinct. Observation of the condition of faeces and the excretion of hooks in the faeces of repeatedly infected dogs revealed that the exclusion of worms started at the first week after the re-infection, and it continued during the patent period. Serum antibodies specific to the parasite antigen increased gradually until the third infection and significantly decreased during the 6-month interval. There was little enhancement of serum antibodies after the fifth infection in most dogs, although no clear correlation was observed between the antibody response and the worm burden. These findings suggested the possibility of developing a vaccine.


Subject(s)
Echinococcosis/drug therapy , Echinococcosis/parasitology , Echinococcus multilocularis/drug effects , Echinococcus multilocularis/immunology , Parasite Load , Animals , Antibodies, Helminth/blood , Antigens, Helminth/analysis , Disease Models, Animal , Dogs , Echinococcus multilocularis/isolation & purification , Feces/parasitology , Parasite Egg Count
4.
J Periodontal Res ; 50(4): 468-78, 2015 Aug.
Article in English | MEDLINE | ID: mdl-25225160

ABSTRACT

BACKGROUND AND OBJECTIVE: The jaw bone, unlike most other bones, is derived from neural crest stem cells, so we hypothesized that it may have different characteristics to bones from other parts of the body, especially in the nature of its periosteum. The periosteum exhibits osteogenic potential and has received considerable attention as a grafting material for the repair of bone and joint defects. MATERIAL AND METHODS: Gene expression profiles of jaw bone and periosteum were evaluated by DNA microarray and real-time polymerase chain reaction. Furthermore, we perforated an area 2 mm in diameter on mouse frontal and parietal bones. Bone regeneration of these calvarial defects was evaluated using microcomputed tomography and histological analysis. RESULTS: The DNA microarray data revealed close homology between the gene expression profiles within the ilium and femur. The gene expression of Wnt-1, SOX10, nestin, and musashi-1 were significantly higher in the jaw bone than in other locations. Microcomputed tomography and histological analysis revealed that the jaw bone had superior bone regenerative abilities than other bones. CONCLUSION: Jaw bone periosteum exhibits a unique gene expression profile that is associated with neural crest cells and has a positive influence on bone regeneration when used as a graft material to repair bone defects. A full investigation of the biological and mechanical properties of jaw bone as an alternative graft material for jaw reconstructive surgery is recommended.


Subject(s)
Mandible/growth & development , Maxilla/growth & development , Periosteum/growth & development , Animals , Bone Development/genetics , Bone Diseases/surgery , Bone Regeneration/genetics , Bone Transplantation/methods , Femur/chemistry , Frontal Bone/pathology , Frontal Bone/surgery , Gene Expression Profiling , Ilium/chemistry , Male , Mandible/chemistry , Maxilla/chemistry , Mice , Mice, Inbred C57BL , Mice, Inbred Strains , Nerve Tissue Proteins/analysis , Nestin/analysis , Oligonucleotide Array Sequence Analysis , Osteogenesis/genetics , Parietal Bone/pathology , Parietal Bone/surgery , Periosteum/chemistry , Periosteum/transplantation , RNA-Binding Proteins/analysis , Random Allocation , Real-Time Polymerase Chain Reaction , SOXE Transcription Factors/analysis , Wnt1 Protein/analysis , X-Ray Microtomography/methods
5.
Int J Geriatr Psychiatry ; 30(11): 1105-13, 2015 Nov.
Article in English | MEDLINE | ID: mdl-26280153

ABSTRACT

OBJECTIVE: To investigate the diagnostic performance of brain acetylcholinesterase (AChE) activity measurement using N-[(11) C]-methyl-4-piperidyl acetate (MP4A) and PET in patients with dementia with Lewy bodies (DLB) and Alzheimer's disease (AD). METHODS: Participants were 14 DLB patients, 25 AD patients and 18 age-matched healthy controls (HC). All subjects underwent PET scans and MP4A to measure regional brain AChE activity. We performed anatomical standardization of each brain image, and k3 values, an index of AChE activity, in each voxel were estimated by nonlinear least squares analysis. Volumes of interest (VOIs) were identified on parametric k3 images in frontal, temporal, parietal and occipital cortices, and in anterior and posterior cingulate gyri (ACG and PCG). In each VOI, the differential diagnostic performance between AD and DLB of k3 values was assessed by area under the curve (AUC) of the receiver-operating characteristic. Voxel-based statistical analyses were also performed. RESULTS: Mean cortical AChE activities in AD patients (-8.2% compared with normal mean) and DLB patients (-27.8%) were lower than HCs (p < 0.05, p < 0.001, respectively). There was a significant difference in mean cortical AChE activities between AD and DLB patients (p < 0.001). All regional brain AChE activities of defined VOIs except ACG were able to well discriminate DLB from AD, and notably performance was the most significant in PCG (AUC = 0.989, 95% CI: 0.965-1.000). CONCLUSIONS: Brain cholinergic deficit is consistently prominent in DLB compared with AD. PET measurement of brain AChE activity may be useful for the differential diagnosis between DLB and AD.


Subject(s)
Acetylcholinesterase/metabolism , Alzheimer Disease/diagnostic imaging , Lewy Body Disease/diagnostic imaging , Positron-Emission Tomography , Aged , Aged, 80 and over , Alzheimer Disease/metabolism , Analysis of Variance , Case-Control Studies , Cerebral Cortex/metabolism , Diagnosis, Differential , Female , Humans , Lewy Body Disease/metabolism , Male , Middle Aged , Piperidines , ROC Curve
6.
Exp Cell Res ; 319(8): 1220-8, 2013 May 01.
Article in English | MEDLINE | ID: mdl-23500413

ABSTRACT

Cancer stem cells (CSCs) are among the target cells of cancer therapy because they are uniquely involved in both cancer progression and sensitivity to chemotherapeutic agents. We identified side population (SP) cells, which are known to be an enriched population of CSC, in five oral squamous cell carcinoma (OSCC) cells (SCC9, SCC25, TOSCC7, TOSCC17, and TOSCC23). The percentages of SP cells ranged from 0% to 3.3%, with TOSCC23 cells showing the highest percentages of SP cells (3.3% of the total cell population). The SP cells isolated from TOSCC23 cells also showed greater cell proliferation and invasion compared to non-SP (MP) cells. Therefore, our initial findings suggested that SP cells were enriched for CSC-like cells. Furthermore, DNA microarray analysis revealed that the expression of cell proliferation-related and anti-apoptotic genes was greater in SP cells compared to MP cells. We focused on Lin28a, which showed the highest expression (approximately 22-fold) among the upregulated genes. The overexpression of Lin28a in TOSCC23 cells increased their proliferation, colony formation, and invasion. These findings suggest that Lin28a is an appropriate CSC target molecule for OSCC treatment.


Subject(s)
Carcinoma, Squamous Cell/genetics , Carcinoma, Squamous Cell/pathology , DNA-Binding Proteins/physiology , Mouth Neoplasms/genetics , Mouth Neoplasms/pathology , Neoplastic Stem Cells/pathology , Cell Line, Tumor , Cell Proliferation , DNA-Binding Proteins/genetics , Gene Expression Profiling , Gene Expression Regulation, Neoplastic , Humans , Microarray Analysis , Neoplasm Invasiveness , Neoplastic Stem Cells/metabolism , Neoplastic Stem Cells/physiology , RNA-Binding Proteins , Stem Cell Niche/genetics , Transfection , Tumor Microenvironment/genetics
7.
J Dent Res ; 103(2): 156-166, 2024 02.
Article in English | MEDLINE | ID: mdl-38058147

ABSTRACT

Autophagy is one of the intracellular degradation pathways and maintains cellular homeostasis, regulating the stress response, cell proliferation, and signal transduction. To elucidate the role of autophagy in the maintenance of dental epithelial stem cells and the subsequent enamel formation, we analyzed autophagy-deficient mice in epithelial cells (Atg7f/f;KRT14-Cre mice), focusing on the influence of aging and stress environments. We also performed in vitro cell and organ culture experiments with an autophagy inhibitor. In young Atg7f/f;KRT14-Cre mice, morphological change was not obvious in maxillary incisors, except for the remarkable cell death in the stratum intermedium of the transitional stage. However, under stress conditions of hyperglycemia, the incisor color changed to white in diabetes Atg7f/f;KRT14-Cre mice. Regarding dental epithelial stem cells, the shape of the apical bud region of the incisor became irregular with age, and odontoma was formed in aged Atg7f/f;KRT14-Cre mice. In addition, the shape of apical bud culture cells of Atg7f/f;KRT14-Cre mice became irregular and enlarged atypically, with epigenetic changes during culture, suggesting that autophagy deficiency may induce tumorigenesis in dental epithelial cells. The epigenetic change and upregulation of p21 expression were induced by autophagy inhibition in vivo and in vitro. These findings suggest that autophagy is important for the regulation of stem cell maintenance, proliferation, and differentiation of ameloblast-lineage cells, and an autophagy disorder may induce tumorigenesis in odontogenic epithelial cells.


Subject(s)
Aging , Ameloblasts , Mice , Animals , Epithelial Cells , Autophagy , Carcinogenesis
8.
Oncology ; 78 Suppl 1: 125-30, 2010 Jul.
Article in English | MEDLINE | ID: mdl-20616594

ABSTRACT

Here we described our strategies to attain a better prognosis for hepatocellular carcinoma (HCC) patients by surgery. Among a variety of attempts conducted to date, we focused on anatomical resection and intraoperative contrast-enhanced ultrasonography. There are still controversies with respect to the significance of anatomical resection. We analyzed the significance of this surgical procedure in 207 patients without macrovascular invasion. These patients underwent either anatomical resection or non-anatomical resection. We found that the patients with anatomical resection had higher recurrence-free survival rate than those with non-anatomical resection. Univariable analysis showed that liver damage, the serum level of alpha-fetoprotein, tumor number, surgical margin, and type of surgery (anatomical or non-anatomical resection) were significant predictive factors for intrahepatic recurrence. Multivariable analysis revealed that multiple tumors, alpha-fetoprotein, and non-anatomical resection were independent risk factors for recurrence. We conclude that anatomical resection is a recommendable surgical procedure in patients without macrovascular invasion. A recent innovation is the development of contrast-enhanced ultrasonography. Then we have applied this to liver surgery intraoperatively. We confirm that vascular images contribute to a precise diagnosis and the detection of small portal tumor thrombi, and that Kupffer images are useful to discover the minute tumors. In addition, by clarifying the relationship between tumors and the vascular architecture, real-time 3-dimensional images using Kupffer imaging are a promising guide during the surgical procedures, although further development is needed.


Subject(s)
Carcinoma, Hepatocellular/surgery , Hepatectomy , Liver Neoplasms/surgery , Ultrasonography, Interventional , Aged , Carcinoma, Hepatocellular/diagnostic imaging , Carcinoma, Hepatocellular/pathology , Female , Humans , Liver Neoplasms/diagnostic imaging , Liver Neoplasms/pathology , Male , Neoplasm Recurrence, Local/diagnosis , Prognosis , Survival Rate
9.
Science ; 368(6491): 654-659, 2020 05 08.
Article in English | MEDLINE | ID: mdl-32381723

ABSTRACT

The near-Earth asteroid (162173) Ryugu is thought to be a primitive carbonaceous object that contains hydrated minerals and organic molecules. We report sample collection from Ryugu's surface by the Hayabusa2 spacecraft on 21 February 2019. Touchdown images and global observations of surface colors are used to investigate the stratigraphy of the surface around the sample location and across Ryugu. Latitudinal color variations suggest the reddening of exposed surface material by solar heating and/or space weathering. Immediately after touchdown, Hayabusa2's thrusters disturbed dark, fine grains that originate from the redder materials. The stratigraphic relationship between identified craters and the redder material indicates that surface reddening occurred over a short period of time. We suggest that Ryugu previously experienced an orbital excursion near the Sun.

10.
Transplant Proc ; 51(5): 1522-1524, 2019 Jun.
Article in English | MEDLINE | ID: mdl-31010697

ABSTRACT

INTRODUCTION: Portal vein thrombosis (PVT) and portal vein stenosis (PVS) are rare complications after liver transplantation that can lead to graft failure and patient death. MATERIAL AND METHODS: The aim of this study was to evaluate the effect of interventional treatment for PVT and PVS occlusion after liver transplantation. Follow-up data of 7 patients who underwent stent replacement for PVT and/or PVS were analyzed. The clinical success, complications, and portal vein patency were analyzed. RESULTS: Clinical success was obtained in 6 of the 7 patients. No portal hypertension-related symptoms reoccurred in the 6 patients during the follow-up. CONCLUSIONS: Interventional radiologic treatment produced a high success rate and a favorable long-term outcome.


Subject(s)
Liver Transplantation , Portal Vein/surgery , Postoperative Complications/surgery , Radiology, Interventional/methods , Vascular Diseases/surgery , Adult , Aged , Constriction, Pathologic/etiology , Constriction, Pathologic/surgery , Female , Humans , Living Donors , Male , Middle Aged , Retrospective Studies , Stents , Treatment Outcome , Vascular Diseases/etiology , Venous Thrombosis/etiology , Venous Thrombosis/surgery
11.
Transplant Proc ; 51(5): 1520-1521, 2019 Jun.
Article in English | MEDLINE | ID: mdl-31155186

ABSTRACT

BACKGROUND: For most patients with liver failure receiving maintenance renal replacement therapy (RRT), treatment with living-donor liver transplantation (LDLT) alone is indicated in Japan. MATERIAL AND METHODS: We retrospectively reviewed patients who underwent LDLT while receiving RRT in our hospital. RESULTS: Three of the 5 patients who underwent LDLT while on RRT died during the first year after transplantation. CONCLUSIONS: The indications for liver transplantation in patients on RRT require careful examination.


Subject(s)
Liver Failure/complications , Liver Transplantation/methods , Renal Insufficiency/complications , Renal Replacement Therapy , Adult , Female , Humans , Japan , Liver Failure/surgery , Liver Transplantation/mortality , Living Donors , Male , Middle Aged , Renal Insufficiency/therapy , Renal Replacement Therapy/mortality , Retrospective Studies
12.
Kyobu Geka ; 61(3): 254-7, 2008 Mar.
Article in Japanese | MEDLINE | ID: mdl-18323196

ABSTRACT

63-year-old man was admitted to our hospital with fever and cough for about 2 months. Laboratory data showed marked inflammatory changes, and chest computed tomography (CT) scans revealed right-sided hydrothorax, atelectasis of the right middle lobe, and a cystic mass in the right middle lobe. We diagnosed the patients as having lung abscess and empyema. Following the intravenous antibiotic chemotherapy, symptoms and laboratory data showed the improvement, however, on the 11th hospital day, he developed high fever again. A chest CT showed pneumopyothorax suggesting the rupture of lung abscess. Since the chest tube drainage was ineffective, open chest surgery was performed. Curettage of both thoracic and abscess cavity with closure of air leakage successfully cured the pyothorax.


Subject(s)
Lung Abscess/complications , Lung Abscess/surgery , Pneumothorax/etiology , Drainage , Humans , Male , Middle Aged , Rupture, Spontaneous , Thoracic Surgical Procedures
13.
Proc Inst Mech Eng H ; 221(5): 537-46, 2007 Jul.
Article in English | MEDLINE | ID: mdl-17822155

ABSTRACT

To establish medical use of tissue engineering technology for ligament and tendon injuries, a scaffold was developed which has sufficient ability for cell growth, cell differentiation, and mechanical properties. The scaffold made from chitosan and 0.1 per cent hyaluronic acid has adequate biodegradability and biocompatibility. An animal experiment showed that the scaffold has less toxicity and less inflammation induction. Furthermore, in-vivo animal experiments showed that the mechanical properties of the engineered ligament or tendon had the possibility to stabilize the joint. It was shown that newly developed hybrid-polymer fibre scaffold has feasibility for joint tissue engineering.


Subject(s)
Chitosan/chemistry , Fibroblasts/cytology , Guided Tissue Regeneration/instrumentation , Hyaluronic Acid/chemistry , Ligaments/growth & development , Tendons/growth & development , Tissue Engineering/instrumentation , Animals , Biocompatible Materials/chemistry , Cell Proliferation , Cells, Cultured , Elasticity , Equipment Design , Equipment Failure Analysis , Feasibility Studies , Fibroblasts/physiology , Guided Tissue Regeneration/methods , Ligaments/cytology , Materials Testing , Rabbits , Tendons/cytology , Tensile Strength , Tissue Engineering/methods
14.
Acta Gastroenterol Belg ; 79(3): 367-369, 2016.
Article in English | MEDLINE | ID: mdl-27821034

ABSTRACT

We report a case of primary gastric diffuse large B-cell lymphoma (DLBCL), de novo DLBCL without the features of mucosa-associated lymphoid tissue (MALT) lymphoma, which regressed after Helicobacter pylori (HP) eradication. A 27-year-old Japanese female with epigastralgia was revealed to have ulcerated lesions in the angle and antral regions on gastroscopy. Biopsy specimen was consistent with a diagnosis of DLBCL without MALT lymphoma component, indicating de novo development. Her clinical staging on the Lugano system was Stage I. HP was positive on a rapid urease test, and she received HP eradication therapy twice, because the first therapy was not successful. On gastroscopy performed 1 month after the second HP eradication therapy, no ulcerated lesion was noted, and the lymphoma cells had regressed histopathologically. (Acta gastro-enterol. belg., 2016, 79, 367-369A).


Subject(s)
Amoxicillin/administration & dosage , Clarithromycin/administration & dosage , Helicobacter Infections , Helicobacter pylori , Lansoprazole/administration & dosage , Lymphoma, Large B-Cell, Diffuse , Metronidazole/administration & dosage , Stomach Neoplasms , Adult , Anti-Bacterial Agents/administration & dosage , Drug Monitoring/methods , Female , Gastroscopy/methods , Helicobacter Infections/complications , Helicobacter Infections/diagnosis , Helicobacter Infections/drug therapy , Helicobacter pylori/drug effects , Helicobacter pylori/isolation & purification , Humans , Lymphoma, Large B-Cell, Diffuse/complications , Lymphoma, Large B-Cell, Diffuse/drug therapy , Lymphoma, Large B-Cell, Diffuse/pathology , Neoplasm Staging , Stomach Neoplasms/complications , Stomach Neoplasms/drug therapy , Stomach Neoplasms/pathology , Treatment Outcome
15.
Biochim Biophys Acta ; 1251(2): 205-9, 1995 Sep 06.
Article in English | MEDLINE | ID: mdl-7669812

ABSTRACT

To study the mechanism of regulation and structure/function relationship of the Pleurotus ostreatus manganese (II) peroxidase (MnP), we amplified the full-length genomic and complementary DNAs for the major isozyme of the MnP mainly by the cassette-primer PCR technique and then sequenced them. The cDNA contained an open reading frame of 1083 bp encoding for a polypeptide of 361 amino-acid residues, including the suggested signal peptide of 29 amino-acid residues with a prepro structure. The predicted amino-acid sequence of the protein shared several common characteristics with those of fungal lignin and manganese (II) peroxidases. We could find a suggested metal response element and two heat-shock element-like sequences in the 5'-flanking region of the structural gene. The structural gene contained 15 introns, many of which lie identical to those in lignin peroxidase genes rather than to those in the known MnP genes.


Subject(s)
DNA, Complementary/chemistry , Peroxidases/genetics , Polyporaceae/enzymology , Amino Acid Sequence , Base Sequence , Molecular Sequence Data , Polyporaceae/genetics , Sequence Alignment
16.
Biochim Biophys Acta ; 1396(1): 27-31, 1998 Mar 04.
Article in English | MEDLINE | ID: mdl-9524211

ABSTRACT

Genomic and cDNA fragments encoding the iron-sulfur protein (Ip) subunit of dehydrogenase (EC 1.3.99.1) have been cloned from the edible basidiomycetous fungus, Pleurotus ostreatus. The gene is interrupted by five introns and is predicted to encode a polypeptide of 268 amino acid residues. Sequence comparison with the Ip subunit from other species identified three conserved cysteine-rich clusters. One of these contains a critical histidine residue implicated in carboxin sensitivity in the heterobasidiomycete Ustilago maydis.


Subject(s)
Fungal Proteins/genetics , Iron-Sulfur Proteins/genetics , Polyporaceae/genetics , Succinate Dehydrogenase/genetics , Amino Acid Sequence , Base Sequence , Cloning, Molecular , DNA, Complementary/isolation & purification , Molecular Sequence Data , Polymerase Chain Reaction , Polyporaceae/enzymology , Sequence Homology, Amino Acid
17.
Biochim Biophys Acta ; 1446(1-2): 126-34, 1999 Jul 07.
Article in English | MEDLINE | ID: mdl-10395925

ABSTRACT

The most unique feature in the replication of mitochondrial DNA (mtDNA) is that most of the newly synthesized heavy strands (H-strands) terminate prematurely, resulting in the formation of displacement loop (D-loop) strands. Only the H-strand which proceeds past the termination site is a true nascent H-strand leading to the overall replication on a circular mtDNA molecule. The physiological significance of the D-loop formation has long been unclear. To examine the role of premature termination in mtDNA replication, we therefore developed a method for selectively measuring both the total amount of nascent H-strands and the amount of true nascent H-strands using ligation-mediated polymerase chain reaction, which, for the first time, enabled us to estimate the frequency of premature termination. The stimulation of cell proliferation with interleukin 2 and phytohemagglutinin in human peripheral T lymphocytes caused an increase in the net replication rate of mtDNA. In stimulated cells, in comparison to resting ones, the amount of true nascent H-strands increased approx. 2.6-fold while the total amount of nascent H-strands remained unchanged, indicating that premature termination decreased while the initiation of replication remained the same. Our findings thus demonstrate the first clear example that premature termination plays a primary role in the up-regulation of the net rate of mtDNA replication in human cells.


Subject(s)
DNA Replication/genetics , DNA, Mitochondrial/metabolism , T-Lymphocytes/metabolism , Aphidicolin/pharmacology , Cell Division/drug effects , Cells, Cultured , Enzyme Inhibitors/pharmacology , Humans , Jurkat Cells , Mitogens/pharmacology , Polymerase Chain Reaction , T-Lymphocytes/drug effects , Up-Regulation
18.
J Am Coll Cardiol ; 14(3): 589-94; discussion 595-6, 1989 Sep.
Article in English | MEDLINE | ID: mdl-2768708

ABSTRACT

It is not known whether coronary vasospasm is associated with coronary thrombosis. In this study, plasma levels of fibrinopeptide A during anginal attacks in 24 patients with variant angina were examined. A hyperventilation test was used to induce angina. Hyperventilation induced angina and ST segment elevation (AST: 0.32 +/- 0.14 mV, p less than 0.01) in eight patients with variant angina. Fibrinopeptide A increased from 0.75 +/- 0.27 at control to 7.8 +/- 4.4 ng/ml (p less than 0.01) during anginal attacks in these eight patients. In addition, four patients had spontaneous attacks of angina; they also had elevated levels of fibrinopeptide A during attacks (from 2.0 +/- 1.2 at control to 21.9 +/- 18.0 ng/ml [p less than 0.01] during attacks). Hyperventilation did not induce either angina or ST segment elevation in 12 of the patients with variant angina. Fibrinopeptide A levels did not change with hyperventilation in these patients. To determine whether elevated plasma levels of fibrinopeptide A were associated with angina, the plasma levels of fibrinopeptide A were examined during exercise-induced angina in seven additional patients with stable effort angina. They all developed angina with treadmill exercise; however, plasma fibrinopeptide A did not change. Therefore, only the patients with variant angina demonstrated elevated levels of fibrinopeptide A during anginal attacks. These findings suggest that coronary vasospasm associated with myocardial ischemia may induce stasis of blood, resulting in fibrinogen-fibrin conversion in the coronary vessels.


Subject(s)
Angina Pectoris, Variant/blood , Fibrinogen/metabolism , Fibrinopeptide A/metabolism , Angina Pectoris, Variant/diagnostic imaging , Angina Pectoris, Variant/physiopathology , Blood Coagulation , Coronary Angiography , Electrocardiography , Exercise Test , Female , Humans , Male , Monitoring, Physiologic
19.
J Dent Res ; 84(3): 234-9, 2005 Mar.
Article in English | MEDLINE | ID: mdl-15723862

ABSTRACT

Protein kinase C (PKC) is an important molecule involved in various cell function, and mediates induced secretion of vascular endothelial growth factor (VEGF). It is hypothesized that PKC and VEGF may be associated with tooth development. Using the laser microdissection method and real-time reverse-transcription-polymerase chain-reaction (RT-PCR), we investigated the expression of PKC betaI and betaII, VEGF, and amelogenin (used as a marker of differentiation to ameloblasts) in the inner and outer enamel epithelia, stellate reticulum, and dental papilla in each stage of the dental germ. We found that the expression levels of PKC betaI and betaII were increased in the inner enamel epithelium during the early bell stage. In addition, the increased expression levels of PKC betaI and betaII were accompanied by increased VEGF expression. These results indicate that PKC betaI, betaII, and VEGF are closely associated with the differentiation of the inner enamel epithelium to ameloblasts.


Subject(s)
Enamel Organ/cytology , Isoenzymes/analysis , Odontogenesis/physiology , Protein Kinase C/analysis , Vascular Endothelial Growth Factor A/analysis , Ameloblasts/cytology , Ameloblasts/enzymology , Amelogenin , Animals , Cell Differentiation , Dental Enamel Proteins/analysis , Dental Papilla/cytology , Dental Papilla/enzymology , Enamel Organ/enzymology , Epithelial Cells/cytology , Epithelial Cells/enzymology , Gene Expression Regulation, Enzymologic , Lasers , Microdissection , Protein Kinase C beta , Rats , Rats, Sprague-Dawley , Reverse Transcriptase Polymerase Chain Reaction , Tooth Germ/cytology , Tooth Germ/enzymology
20.
J Bone Joint Surg Br ; 87(9): 1278-84, 2005 Sep.
Article in English | MEDLINE | ID: mdl-16129759

ABSTRACT

Sex hormones play important roles in the regulation of the proliferation, maturation and death of chondrocytes in the epiphyseal growth plate. We have investigated the effects of male castration on the cell kinetics of chondrocytes as defined by the numbers of proliferating and dying cells. The growth plates of normal rabbits and animals castrated at eight weeks of age were obtained at 10, 15, 20 and 25 weeks of age. Our study suggested that castration led to an increase in apoptosis and a decrease in the proliferation of chondrocytes in the growth plate. In addition, the number of chondrocytes in the castrated rabbits was less than that of normal animals of the same age.


Subject(s)
Chondrocytes/cytology , Growth Plate/cytology , Testosterone/physiology , Animals , Apoptosis/physiology , Caspase 3 , Caspases/metabolism , Cell Proliferation , Femur/growth & development , Growth Plate/metabolism , Male , Orchiectomy , Osteonectin/metabolism , Rabbits , Testosterone/blood
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