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1.
Acta Endocrinol (Buchar) ; 19(2): 241-244, 2023.
Article in English | MEDLINE | ID: mdl-37908876

ABSTRACT

Background: Graves' disease results in various clinical cardio-pulmonary manifestations such as tachycardia, atrial fibrillation, and pulmonary edema. Clinical Case: A 62-year-old woman presented with palpitations and dyspnea. Laboratory and radiologic examination revealed markedly elevated free T4 (4.79 ng/dL), T3 (4.42 ng/mL), lowered TSH (0.01 uIU/mL), atrial fibrillation and multifocal lung haziness. She was initially diagnosed with atrial fibrillation with pulmonary edema, which subsequently changed to pulmonary alveolar proteinosis by further evaluations such as computed tomography and bronchoscopic biopsy. Conclusion: Pulmonary alveolar proteinosis is a rare lung disease. Clinicians should carefully assess lung lesions in thyrotoxicosis patients as they can be easily mistaken for pulmonary edema in clinical practice.

2.
J Appl Microbiol ; 129(1): 116-136, 2020 Jul.
Article in English | MEDLINE | ID: mdl-32141152

ABSTRACT

Probiotics administration in aquafeed is known to increase feed consumption and absorption due to their capacity to release a wide range of digestive enzymes and nutrients which can participate in digestion process and feed utilization, along with the absorption of diet components led to an increase in host's health and well-being. Furthermore, probiotics improve gut maturation, prevention of intestinal disorders, predigestion of antinutrient factors found in the feed ingredients, gut microbiota, disease resistance against pathogens and metabolism. The beneficial immune effects of probiotics are well established in finfish. However, in comparison, similar studies are less abundant in the shellfish. In this review, the discussions will mainly focus on studies reported the last 2 years. In recent studies, native probiotic bacteria were isolated and fed back to their hosts. Although beneficial effects were demonstrated, some studies showed adverse effects when treated with a high concentration. This adverse effect may be due to the imbalance of the gut microbiota caused by the replenished commensal probiotics. Probiotics revealed greatest effect on the shrimp digestive system particularly in the larval and early post-larval stages, and stimulate the production of endogenous enzymes in shrimp and contribute with improved the enzyme activities in the gut, as well as disease resistance.


Subject(s)
Aquaculture , Bacillus/physiology , Dietary Supplements , Lactobacillales/physiology , Probiotics/administration & dosage , Animal Nutritional Physiological Phenomena , Animals , Fishes/immunology , Fishes/microbiology , Gastrointestinal Microbiome , Probiotics/adverse effects , Shellfish/microbiology
3.
Nat Med ; 7(1): 101-7, 2001 Jan.
Article in English | MEDLINE | ID: mdl-11135623

ABSTRACT

The transcription factor early growth response protein 1 (EGR1) is overexpressed in a majority of human prostate cancers and is implicated in the regulation of several genes important for prostate tumor progression. Here we have assessed the effect of Egr1 deficiency on tumor development in two transgenic mouse models of prostate cancer (CR2-T-Ag and TRAMP). Using a combination of high-resolution magnetic resonance imaging and histopathological and survival analyses, we show that tumor progression was significantly impaired in Egr1-/- mice. Tumor initiation and tumor growth rate were not affected by the lack of Egr1; however, Egr1 deficiency significantly delayed the progression from prostatic intra-epithelial neoplasia to invasive carcinoma. These results indicate a unique role for Egr1 in regulating the transition from localized, carcinoma in situ to invasive carcinoma.


Subject(s)
DNA-Binding Proteins/physiology , Immediate-Early Proteins , Neoplasm Proteins , Prostatic Neoplasms/genetics , Transcription Factors/physiology , Animals , DNA-Binding Proteins/genetics , Early Growth Response Protein 1 , Gene Expression Regulation, Neoplastic , Male , Mice , Mice, Transgenic , Precancerous Conditions/pathology , Repressor Proteins/physiology , Transcription Factors/genetics
4.
Science ; 175(4019): 327-8, 1972 Jan 21.
Article in English | MEDLINE | ID: mdl-5008161

ABSTRACT

Repeated administration of ethanol (42 percent of total calories) for 28 days increased serum creatine phosphokinase activity and produced ultrastructural changes in skeletal muscle of human volunteers. The data suggest that alcoholic myopathy results from ethanol toxicity, rather than from nutritional or other factors.


Subject(s)
Ethanol/toxicity , Muscular Diseases/chemically induced , Adult , Biopsy , Creatine Kinase/blood , Diet , Ethanol/pharmacology , Glycogen , Humans , Lipids , Male , Microscopy , Microscopy, Electron , Mitochondria , Muscles/cytology , Muscles/drug effects , Muscles/pathology , Muscular Diseases/pathology , Sarcoplasmic Reticulum
5.
Science ; 172(3984): 733-6, 1971 May 14.
Article in English | MEDLINE | ID: mdl-4324667

ABSTRACT

Black widow spider venom selectively poisons motor nerve endings. A progressive and irreversible failure of neuromuscular transmission occurs in the cat. Electron microscopy of the poisoned nerve-muscle junction shows a sequence of motor nerve ending damage that culminates in disruption of the prejunctional membrane and loss of all organelles, including synaptic vesicles. The postjunctional membrane was morphologically unaffected. After complete poisoning, the contractile response to exogenous acetylcholine was severely impaired, an indication that the prejunctional site is chiefly involved in the contractile response produced by exogenous acetylcholine and that the pre- and postjunctional effects of acetylcholine were separated.


Subject(s)
Motor Neurons/drug effects , Nerve Endings/drug effects , Synaptic Transmission/drug effects , Venoms/pharmacology , Acetylcholine/pharmacology , Animals , Cats , Microscopy, Electron , Muscle Contraction/drug effects , Neuromuscular Junction/drug effects , Poisoning/pathology , Spiders , Venoms/poisoning
6.
Eur Surg Res ; 39(4): 208-15, 2007.
Article in English | MEDLINE | ID: mdl-17396032

ABSTRACT

BACKGROUND: Proteolytic shedding of the ectodomain of a variety of transmembrane proteins, including cell-to-cell adhesion molecules, has been observed in solid cancers. We have investigated whether extracellular cleavage of E-cadherin mediated by matrix metalloproteinase-7 (MMP-7) is involved in hepatocyte growth factor (HGF) induced in vitro invasion in stomach cancer cells. METHODS: The effects of HGF on the expression of E-cadherin/beta-catenin and MMP-7 at both the protein and mRNA levels were assessed in stomach cancer cells, NUGC-3 and MKN-28, and in cells in which the expression of MMP-7 was downregulated by transfection with a MMP-7 short hairpin RNA plasmid. RESULTS: Treatment with HGF increased the extracellular cleavage of E-cadherin and the release of MMP-7 and reduced the level of E-cadherin in a dose- and time-dependent manner. HGF treatment repressed the phosphorylation of beta-catenin in a Triton-soluble fraction, but enhanced this phosphorylation in a Triton-insoluble fraction. The association of E-cadherin with beta-catenin was decreased by HGF treatment in the Triton-soluble fraction. In addition, treatment of MMP-7 short hairpin RNA transfected NUGC-3 cells with HGF resulted in no extracellular cleavage of E-cadherin and also decreased the in vitro cell invasion. CONCLUSIONS: These results suggest that incubation with HGF mediated the release of MMP-7, resulting in extracellular cleavage of E-cadherin from stomach cancer cells. This might be a key mechanism in HGF-induced in vitro invasion and metastasis.


Subject(s)
Adenocarcinoma/metabolism , Cadherins/metabolism , Hepatocyte Growth Factor/pharmacology , Matrix Metalloproteinase 7/metabolism , Stomach Neoplasms/metabolism , Adenocarcinoma/pathology , Cell Line, Tumor , Detergents , Enzyme Activation/drug effects , Extracellular Space/enzymology , Gene Expression Regulation, Enzymologic/drug effects , Humans , In Vitro Techniques , Matrix Metalloproteinase 7/genetics , Mutagenesis , Neoplasm Invasiveness/pathology , Octoxynol , Phosphorylation/drug effects , Solubility , Stomach Neoplasms/pathology , beta Catenin/metabolism
7.
J Neurosci ; 21(17): 6617-25, 2001 Sep 01.
Article in English | MEDLINE | ID: mdl-11517251

ABSTRACT

Tumor necrosis factor-alpha (TNF-alpha) expression has been documented extensively in animal models of traumatic spinal cord injury (SCI). However, the pathophysiological significance of TNF-alpha expression in the injured cord remains to be delineated. The TNF receptor (TNFR)-nuclear factor-kappaB (NF-kappaB) signal transduction pathway is important for maintaining cell viability. NF-kappaB exerts anti-apoptotic effects via an endogenous caspase inhibitory system mediated by cellular inhibitor of apoptosis protein 2 (c-IAP2). NF-kappaB transactivates c-IAP2 to inhibit caspase-3 activation. Progressive cell death, including morphological and biochemical features suggestive of apoptosis, has been noted after SCI. We explored the effects of TNFR1 or TNFR2 deletion on the apoptotic events downstream of NF-kappaB in relation to SCI pathology and functional recovery. Nuclear proteins from the injured cords of the TNFR1(-/-) mice had a reduced NF-kappaB binding activity compared with the wild-type controls. This decrease in NF-kappaB activation was accompanied by a reduction in c-IAP2 expression and an increase in the active form of caspase-3 protein. After SCI the TNFR1(-/-) mice had greater numbers of apoptotic cells, a larger lesion size, and worse functional recovery than wild-type mice. TNFR2-deficient mice had a similar, although not as pronounced, consequence as the TNFR1(-/-) mice. These findings support the argument that the TNFR-NF-kappaB pathway is beneficial for limiting apoptotic cell death after SCI and that a defective TNFR-NF-kappaB pathway results in a poorer neurological outcome. A worse functional outcome in TNFR(-/-) mice suggests that an endogenous apoptosis inhibitory mechanism mediated by TNFR activation, NF-kappaB, and c-IAP2 may be of pathophysiological importance.


Subject(s)
NF-kappa B/metabolism , Proteins/metabolism , Receptors, Tumor Necrosis Factor/deficiency , Recovery of Function , Spinal Cord Injuries/physiopathology , Animals , Antigens, CD/genetics , Apoptosis , Axons/pathology , Baculoviral IAP Repeat-Containing 3 Protein , Caspase 3 , Caspases/metabolism , Female , In Situ Nick-End Labeling , Inhibitor of Apoptosis Proteins , Magnetic Resonance Imaging , Mice , Mice, Inbred C57BL , Mice, Knockout , Mice, Transgenic , Motor Activity , Myelin Sheath/metabolism , Receptors, Tumor Necrosis Factor/genetics , Receptors, Tumor Necrosis Factor, Type I , Receptors, Tumor Necrosis Factor, Type II , Signal Transduction/physiology , Spinal Cord/metabolism , Spinal Cord/pathology , Spinal Cord Injuries/genetics , Spinal Cord Injuries/pathology , Ubiquitin-Protein Ligases , Wounds, Nonpenetrating
8.
Stroke ; 32(4): 925-32, 2001 Apr.
Article in English | MEDLINE | ID: mdl-11283393

ABSTRACT

BACKGROUND AND PURPOSE: (23)Na MRI may offer new insight into the evaluation of tissue injury. We performed a direct, longitudinal, morphological comparison of (1)H T2 relaxation, (1)H apparent diffusion coefficient (ADC), (23)Na content, and histopathology after cerebral ischemia to address the hypotheses that (a) (23)Na MRI is unique in comparison to (1)H MRI, and (b) accumulation of (23)Na is an unambiguous marker for dead tissue. METHODS: Rats underwent 30 minutes of focal ischemia. MRIs of (1)H T2, (1)H ADC, and (23)Na content were acquired from 12 hours up to 1, 2, or 14 days after reperfusion. On excision, brains were stained with triphenyltetrazolium chloride (TTC). RESULTS: In all cases, the region of abnormality increased in size for 2 days. On day 5, both (1)H T2 and ADC temporarily appeared normal despite the presence of TTC-defined infarction. By comparison, the volume of tissue exhibiting abnormally intense (23)Na signal mirrored the TTC-defined infarct at all time points. CONCLUSIONS: Regions of high (23)Na content correlate well with the TTC-defined infarct and may be a quantitative in vivo marker for dead tissue. In contrast, the dynamics of the (1)H T2 and ADC make it difficult to interpret these images without additional information because they may appear normal despite infarction. Neither type of (1)H image delineates dead tissue, and none of these methods predicts the potential infarct size at early time points.


Subject(s)
Cerebral Infarction/diagnosis , Ischemic Attack, Transient/diagnosis , Magnetic Resonance Imaging , Protons , Sodium Isotopes , Animals , Biomarkers , Brain/blood supply , Brain/pathology , Carotid Arteries/enzymology , Cerebral Infarction/etiology , Cerebral Infarction/pathology , Disease Models, Animal , Image Processing, Computer-Assisted , Ischemic Attack, Transient/complications , Ischemic Attack, Transient/pathology , Longitudinal Studies , Magnetic Resonance Imaging/methods , Male , Middle Cerebral Artery , Necrosis , Predictive Value of Tests , Rats , Rats, Long-Evans , Sensitivity and Specificity
9.
Am J Surg Pathol ; 13(5): 406-12, 1989 May.
Article in English | MEDLINE | ID: mdl-2712192

ABSTRACT

We present an unusual case of multiple intracranial meningeal nodules in a 30-year-old man. Histologically, the nodules consisted predominantly of plasma cells, histiocytes, and lymphoid cells with Russell bodies and emperipolesis. Emperipolesis may be a clue to understanding the pathogenesis of the process that has features consistent with so-called sinus histiocytosis with massive lymphadenopathy in the extranodal location.


Subject(s)
Lymphatic Diseases/pathology , Meningeal Neoplasms/pathology , Meningioma/pathology , Adult , Humans , Lymph Nodes , Male , Meningeal Neoplasms/complications , Meningeal Neoplasms/diagnostic imaging , Meningioma/complications , Meningioma/diagnostic imaging , Tomography, X-Ray Computed
10.
Cancer Lett ; 136(1): 33-40, 1999 Feb 08.
Article in English | MEDLINE | ID: mdl-10211936

ABSTRACT

Cytotoxic lectins (KML-C) were isolated from an extract of Korean mistletoe [Viscum album C. (coloratum)] by affinity chromatography on a hydrolysed Sepharose 4B column, and the chemical and biological properties of KML-C were examined, partly by comparing them with a lectin (EML-1) from European mistletoe[Viscum album L. (loranthaceae)]. The hemagglutinating activity of KML-C was inhibited by N-acetyl-D-galactosamine and D-galactose at the minimum concentrations of 6.3 and 12.5 microM/ml, respectively. Further biochemical analyses indicated that KML-C consists of four chains (Mr = 27.5, 30, 31 and 32.5 kDa) which, in some of the molecules, are disulfide-linked, and that the chains of KML-C are distributed over a broad range of isoelectric points (pI), 8.0 to 9.0, whereas the range for EML-1 is 6.6-7.0. A difference was also observed between the N-terminal sequences of KML-C and EML-1. The isolated lectins showed strong cytotoxicity against various human and murine tumor cells, and the cytotoxic activity of KML-C was higher than that of EML-1. Tumor cells treated with KML-C exhibited typical patterns of apoptotic cell death, such as apparent morphological changes and DNA fragmentation, and its apoptosis-inducing activity was blocked by addition of Zn2+, an inhibitor of Ca2+/Mg2+ -dependent endonucleases, in a dose-dependent manner. These results suggest that KML-C is a novel lectin related to the cytotoxicity of Korean mistletoe, and that its cytotoxic activity against tumor cells is due to apoptosis mediated by Ca2+/Mg2+ -dependent endonucleases.


Subject(s)
Antineoplastic Agents/pharmacology , Apoptosis/drug effects , Lectins/pharmacology , Mistletoe , Neoplasms/drug therapy , Plant Extracts/pharmacology , Plants, Medicinal , Animals , Antineoplastic Agents/chemistry , Antineoplastic Agents/isolation & purification , Dose-Response Relationship, Drug , Europe , Humans , Korea , Lectins/chemistry , Lectins/isolation & purification , Mice , Neoplasms/physiopathology , Plant Extracts/chemistry , Plant Extracts/isolation & purification , Plant Lectins , Tumor Cells, Cultured
11.
Biochem Pharmacol ; 56(5): 561-7, 1998 Sep 01.
Article in English | MEDLINE | ID: mdl-9783724

ABSTRACT

Treatment of HL-60 cells with thapsigargin, a microsomal Ca2+/ATPase inhibitor, led to depletion of intracellular calcium stores followed by capacitative calcium entry. Stimulation of adenylyl cyclase with forskolin enhanced thapsigargin-induced Ca2+ influx. The forskolin effect was confirmed by enhanced fluorescence quenching induced by Mn2+ entry into fura-2 loaded cells. 1,9-Dideoxy-forskolin, an inactive analog of forskolin, did not affect capacitative calcium entry. On the other hand, phorbol 12-myristate 13-acetate (PMA), an activator of protein kinase C, inhibited thapsigargin-induced Ca2+ entry. Histamine and prostaglandin E2 (PGE2) elevated intracellular adenosine 3':5'-cyclic monophosphate (cAMP) levels and enhanced the thapsigargin-induced capacitative calcium entry. Incubation with N-[2-(p-bromocynnamylamino)ethyl]-5-isoquinolinesulfonamide (H89), an inhibitor of protein kinase A (PKA), blocked the forskolin effect, and GF109203X, an inhibitor of protein kinase C (PKC), blocked the phorbol 12-myristate 13-acetate effect. The results suggest that protein kinase A regulates capacitative calcium entry positively, but that protein kinase C regulates Ca2+ influx negatively. Furthermore, after differentiation of HL-60 promyelocytes with dimethylsulfoxide to granulocytes, the inhibitory effect of phorbol 12-myristate 13-acetate became more pronounced, whereas the stimulatory effect of prostaglandin E2 did not change. This result suggests that the regulation of capacitative calcium entry by protein kinase C and protein kinase A develops differently during differentiation.


Subject(s)
Calcium/metabolism , Cyclic AMP-Dependent Protein Kinases/drug effects , Enzyme Inhibitors/pharmacology , Granulocytes/drug effects , Protein Kinase C/drug effects , Thapsigargin/pharmacology , Calcium-Transporting ATPases/antagonists & inhibitors , Cell Differentiation/drug effects , Colforsin/pharmacology , Cyclic AMP-Dependent Protein Kinases/metabolism , Granulocytes/enzymology , HL-60 Cells , Humans , Protein Kinase C/metabolism , Tetradecanoylphorbol Acetate/pharmacology
12.
Mol Cells ; 7(6): 807-15, 1997 Dec 31.
Article in English | MEDLINE | ID: mdl-9509425

ABSTRACT

To develop an antiviral agent and virus-resistant plants, a cDNA clone encoding Phytolacca insularis antiviral protein (PIP) was isolated from a cDNA library constructed with poly(A)+ RNA purified from leaves of P. insularis. The PIP cDNA contains an open reading frame encoding 307 amino acids. The deduced amino acid sequence includes a putative signal sequence of 22 amino acids at the N-terminus. The amino acid sequence of PIP shares 84% homology with that of the pokeweed antiviral protein (PAP). In addition, the mature PIP exhibits the conserved putative active site found in other ribosome-inactivating proteins (RIPs). Recombinant PIP (rPIP) synthesized in Escherichia coli inhibits protein synthesis in vitro in rabbit reticulocyte lysate through the N-glycosidase activity in a similar manner with other RIPs. Local lesion assays with purified rPIP revealed that it inhibits infection of various viruses to plants. Transgenic potato plants expressing the PIP cDNA under the control of the cauliflower mosaic virus 35S promoter are resistant to viruses, such as potato virus X, potato virus Y, and potato leafroll virus. These results suggest that the PIP cDNA could be used for the development of an antiviral agent and transgenic plants resistant against a broad spectrum of plant viruses infecting through both mechanical and aphid transmission.


Subject(s)
Antiviral Agents/pharmacology , Gene Expression Regulation, Plant/genetics , N-Glycosyl Hydrolases , Plant Proteins/chemistry , Solanum tuberosum/virology , Amino Acid Sequence , Base Sequence , Cloning, Molecular , Escherichia coli/genetics , Molecular Sequence Data , Plant Proteins/pharmacology , Plant Viruses/pathogenicity , Plants, Genetically Modified , Promoter Regions, Genetic/genetics , Protein Biosynthesis/drug effects , Recombinant Proteins/genetics , Recombinant Proteins/pharmacology , Reticulocytes/physiology , Ribosome Inactivating Proteins, Type 1 , Sequence Analysis, DNA , Sequence Homology, Amino Acid , Solanum tuberosum/genetics
13.
Mol Cells ; 12(2): 215-20, 2001 Oct 31.
Article in English | MEDLINE | ID: mdl-11710524

ABSTRACT

We previously isolated a lectin of the Korean mistletoe (Viscum album coloratum). The cDNA clones that encode the A- or the B-chain of the Korean mistletoe lectin were cloned by reverse transcriptase polymerase chain reaction (RT-PCR). The mRNAs that were extracted from the Korean mistletoe were amplified, ligated into the pGEM-T easy vector, and screened with a Korean mistletoe lectin-specific probe. The probe was prepared by PCR amplification of the Korean mistletoe DNA using a primer set designed on the basis of amino acid sequences of the Korean mistletoe lectin that we had purified and reported. Unlike a recent report, which states that the European mistletoe lectin gene has no isoforms, several different clones of the A- and B-chains of the Korean mistletoe lectin were cloned from the same primer set. Three clones of each were selected for sequencing. The sizes of the A-chains were 762, 762, and 768 bp, respectively. The B-chain sizes were 798, 789, and 789 bp, respectively. Each of the clones showed significant variation in the amino acids sequence, including the N-linked glycosylation sites of the lectin. The sequence analysis of each of the Korean lectin clones, in comparison with the European mistletoe lectin and the other type II ribosome binding proteins, is discussed in the text. In addition, Southern blot analysis of the Korean mistletoe genomic DNA, restricted by different enzymes and hybridized with the lectin DNA, showed multi-bands, supporting the existence of multicopy genes or a gene family. These data suggest that heterogeneity of the mistletoe lectin is not only introduced by post-translational modifications, but also by expression of isotypes of the lectin genes.


Subject(s)
Genes, Plant , Lectins/genetics , Viscum album/genetics , Amino Acid Sequence , Base Sequence , Blotting, Southern , Cloning, Molecular , DNA Probes , DNA, Complementary/genetics , DNA, Plant/genetics , Korea , Lectins/chemistry , Molecular Sequence Data , Plant Lectins , Reverse Transcriptase Polymerase Chain Reaction , Sequence Homology, Amino Acid , Sequence Homology, Nucleic Acid
14.
Eur J Pharmacol ; 322(2-3): 265-73, 1997 Mar 19.
Article in English | MEDLINE | ID: mdl-9098697

ABSTRACT

We investigated the cross-talk between the histamine and ATP receptors in HL-60 human promyelocytes. While both histamine and extracellular ATP increase intracellular Ca2+ concentration ([Ca2+]i) we found that histamine treatment causes a decrease in the subsequent ATP-induced Ca2+ release from intracellular stores and Ca2+ influx from extracellular space. In addition, histamine also inhibited the subsequent ATP-induced inositol 1.4,5-trisphosphate (IP3) generation in a manner comparable to the Ca2+ release. However, histamine did not inhibit thapsigargin-induced Ca2+ release and influx, thus indicating that histamine does not directly inhibit the Ca2+ release-activated channel (CRAC). Ca2+ elevation induced by 2'- and 3'-O-(4-benzoylbenzoyl) ATP (BzATP), which does not produce IP3, was also inhibited by treatment with histamine, suggesting the presence of ATP-gated channels that are regulated by histamine. Treatment with dibutyryl cAMP or 8-bromo-cAMP inhibited the subsequent ATP-induced response similar to histamine. Moreover, the incubation of cells with N-[2-(p-bromocinnamylamino)ethyl]-5-isoquinolinesulfonamide (H89), a protein kinase A inhibitor abolished histamine's inhibitory effect on the ATP-induced [Ca2+]i rise and IP3 formation. These results suggest that histamine inhibits both ATP-induced IP3 production and ATP-activated channel opening, through protein kinase A activation.


Subject(s)
Adenosine Triphosphate/pharmacology , Calcium/metabolism , Cyclic AMP-Dependent Protein Kinases/metabolism , Histamine/pharmacology , Cyclic AMP/metabolism , Enzyme Activation , HL-60 Cells , Humans , Signal Transduction
15.
J Neurosurg ; 91(5): 814-21, 1999 Nov.
Article in English | MEDLINE | ID: mdl-10541239

ABSTRACT

OBJECT: Surgical treatment of gliomas is difficult because they are invasive. Invasion of essential cortex often limits or precludes surgical resection. A tumor model was developed in which the rodent whisker barrel cortex was used to examine how gliomas affect cortical function and structure. METHODS: Both DBT (mouse) and C6 (rat) glioma cell lines were grown in culture and labeled with the fluorescent marker Dil in vitro. Labeled tumor cells were then injected into the whisker barrel cortex of adult mice and rats. Neurological assessments were made daily and magnetic resonance (MR) images were obtained. Animals were killed by perfusion 6 to 14 days after injection, and histological sections were prepared and studied. Tumors were found in all 20 rats and 10 mice that had been injected with the C6 and DBT cell lines, respectively. The animal cells had been labeled with Dil in vitro, and all in vivo tumors proved to be Dil positive. The MR images revealed the tumor locations and serial MR images demonstrated tumor growth. Histological evaluation confirmed the location of the tumor and the disruption of barrel cortex architecture. CONCLUSIONS: Both DBT and C6 glioma cell lines can be used to generate malignant glial tumors reproducibly in the whisker barrel cortex. Fluorescent labeling and cytochrome oxidase staining permit visualization of tumor growth patterns, which disrupt the barrel cortex by microscopic invasion and by gross tissue deformation. Magnetic resonance imaging demonstrates the anatomical extension of these tumors in live rodents. Using this model for further studies on the effects of malignant glioma growth on functional cerebral cortex should advance our understanding of the neurological issues and management of patients with these tumors.


Subject(s)
Brain Neoplasms/pathology , Disease Models, Animal , Glioblastoma/pathology , Rats, Wistar , Somatosensory Cortex/pathology , Animals , Electron Transport Complex IV/analysis , Magnetic Resonance Imaging , Male , Mice , Mice, Inbred BALB C , Microscopy, Fluorescence , Neoplasm Transplantation , Rats , Somatosensory Cortex/enzymology , Tumor Cells, Cultured , Vibrissae/innervation
16.
J Biosci Bioeng ; 87(1): 112-5, 1999.
Article in English | MEDLINE | ID: mdl-16232436

ABSTRACT

Scanning electron microscopy and energy dispersive X-ray analyses were carried out in a comparative investigation of Pb(2+) accumulation in Saccharomyces cerevisiae and Aureobasidium pullulans. In S. cerevisiae, the time required to reach an equilibrium state was shortened from 100 h to 1 h as the initial Pb(2+) concentration decreased from 96.5 mg/l to 16.0 mg/l, whereas the time was almost independent of initial Pb(2+) concentration in A. pullulans. Concomitant with the Pb(2+) accumulation, the cell surface of S. cerevisiae became rough and the amounts of potassium, phosphorus and sulfur on the cell surface decreased. However, significant increase of Pb(2+) on the cell surface after Pb(2+) accumulation was not observed due to Pb(2+) penetration into the cell interior. In contrast, the Pb(2+) accumulation had no significant effect on the surface characteristics of A. pullulans and extreme Pb(2+) accumulation was observed on the cell surface because Pb(2+) could not penetrate into the cell interior due to the existence of extracellular polymeric substances.

17.
J Biosci Bioeng ; 87(3): 291-5, 1999.
Article in English | MEDLINE | ID: mdl-16232470

ABSTRACT

In an attempt to utilize the whole cell as a biocatalyst for inulo-oligosaccharide (IOS) production from inulin, the endoinulinase gene (inu1) of Pseudomonas sp. was cloned into the plasmid pBR322 using EcoRI restriction endonuclease and Escherichia coli HB101 as the host strain. The endoinulinase from E. coli HB101/pKMG50 was constitutively expressed, producing a high yield of IOS (78%). In a batchwise reaction, the initial enzyme concentration determined the total oligosaccharide yield, and excess enzyme decreased the total oligosaccharide yield due to the formation of high amounts of free sugars such as glucose and fructose. The recombinant E. coli expressing endoinulinase activity were immobilized on a polystyrene carrier material, resulting in a dramatically enhanced thermal stability of the enzyme. Continuous production of IOS from inulin was also carried out at 50 degrees C using a bioreactor packed with the immobilized cells. Under the optimal operation conditions, continuous production of IOS was achieved with a productivity of 150 g/l.h for 17 d at 50 degrees C without significant loss of initial activity.

18.
Bioresour Technol ; 79(1): 99-102, 2001 Aug.
Article in English | MEDLINE | ID: mdl-11396916

ABSTRACT

Pb2+ accumulation by Saccharomyces cerevisiae and Aureobasidium pullulans was inhibited by the initial Pb2+ concentration. In the case of S. cerevisiae, as initial Pb2+ concentrations increased, the accumulated Pb2+ per unit cell dry weight at equilibrium and the time required to reach an equilibrium state increased at low initial Pb2+ concentration. On the contrary, the accumulated Pb2+ decreased at high initial Pb2+ concentration at all pH values. The inhibition effect of initial Pb2+ concentration was delayed by the decrease of pH. However, the maximal Pb2+ accumulation capacity of S. cerevisiae was almost constant regardless of pH values. In the case of A. pullulans, the time required to reach an equilibrium state was independent of the initial Pb2+ concentration. The maximal Pb2+ accumulation capacity of A. pullulans decreased according to the decrease of pH values. However, the initial Pb2+ concentration needed to reach maximal Pb2+ accumulation amount was almost constant.


Subject(s)
Lead/pharmacology , Mitosporic Fungi/drug effects , Saccharomyces cerevisiae/drug effects , Waste Disposal, Fluid/methods , Adsorption , Hydrogen-Ion Concentration , Lead/pharmacokinetics , Mitosporic Fungi/metabolism , Saccharomyces cerevisiae/metabolism
19.
J Toxicol Sci ; 18(1): 21-9, 1993 Feb.
Article in English | MEDLINE | ID: mdl-8386259

ABSTRACT

Selectivity of lead effect on dopamine beta-hydroxylase activity in regions of brai nfrom rats postnatally exposed to lead was tested. Three groups of animals were prepared; (1) Rats exposed to lead at a low dose (0.05% PbAcetate: PbAc); (2) Rats exposed to lead at a high dose (0.2% PbAc); (3) Age-matched normal control rats. At 2, 4, 6 and 8 weeks of age weight of whole brain and body in each group were measured. At the same ages activities of dopamine beta-hydroxylase and Na+K(+)-ATPase were measured in 5 brain regions of each animal. Exposure of rats to lead generally decreased Na+/K(+)-ATPase activity and showed alternative changes of dopamine beta-hydroxylase activity were detected without concomitant changes of Na+/K(+)-ATPase activity were telencephalon and pons/medulla at 2 weeks of age and telencephalon, diencephalon and pons/medulla at 4 weeks of age and midbrain and pons/medulla at 6 weeks of age and cerebellum at 8 weeks of age in rats exposed to lead at a low dose, and those in rats exposed to lead at a high dose were midbrain at 6 weeks of age and cerebellum at 8 weeks of age. These data imply that noradrenergic nervous system in the brain regions described above could selectively be affected by lead.


Subject(s)
Brain/drug effects , Dopamine beta-Hydroxylase/metabolism , Lead/toxicity , Age Factors , Animals , Brain/enzymology , Dopamine beta-Hydroxylase/drug effects , Dose-Response Relationship, Drug , Female , Male , Rats , Rats, Wistar , Sodium-Potassium-Exchanging ATPase/drug effects , Sodium-Potassium-Exchanging ATPase/metabolism
20.
Appl Biochem Biotechnol ; 28-29: 99-109, 1991.
Article in English | MEDLINE | ID: mdl-1929394

ABSTRACT

The effectiveness of pretreatments on hardwood substrate was investigated in connection with its subsequent conversion by simultaneous saccharification and fermentation (SSF), using Clostridium acetobutylicum. The main objectives of the pretreatment were to achieve efficient separation of lignin from carbohydrates, and to obtain maximum sugar yield on enzymatic hydrolysis of pretreated wood. Two methods have given promising results: (1) supercritical CO2-SO2 treatment, and (2) monoethanolamine (MEA) treatment. The MEA pretreatment removed above 90% of hardwood lignin while retaining 83% of carbohydrates. With CO2-SO2 pretreatment, the degree of lignin separation was lower. Under the scheme of SSF, the pretreated hardwood was converted to acetone, butanol, and ethanol (ABE) via single stage processing by cellulase enzyme system and C. acetobutylicum cells. The product yield in the process was such that 15 g of ABE/100 g of dry aspen wood was produced. In the overall process of SSF, the enzymatic hydrolysis was found to be the rate-limiting step. The ability of C. acetobutylicum to metabolize various 6-carbon and 5-carbon sugars resulted in efficient utilization of all available sugars from hardwood.


Subject(s)
Clostridium/metabolism , Wood , Acetone , Butanols , Cellulose/metabolism , Fermentation , Hydrolysis , Indicators and Reagents , Lignin/isolation & purification , Thermodynamics
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