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1.
Science ; 381(6659): 748-753, 2023 08 18.
Article in English | MEDLINE | ID: mdl-37590351

ABSTRACT

During the consumption of alkanes, Alcanivorax borkumensis will form a biofilm around an oil droplet, but the role this plays during degradation remains unclear. We identified a shift in biofilm morphology that depends on adaptation to oil consumption: Longer exposure leads to the appearance of dendritic biofilms optimized for oil consumption effected through tubulation of the interface. In situ microfluidic tracking enabled us to correlate tubulation to localized defects in the interfacial cell ordering. We demonstrate control over droplet deformation by using confinement to position defects, inducing dimpling in the droplets. We developed a model that elucidates biofilm morphology, linking tubulation to decreased interfacial tension and increased cell hydrophobicity.


Subject(s)
Alcanivoraceae , Alkanes , Biofilms , Petroleum , Alcanivoraceae/metabolism , Alkanes/metabolism , Petroleum/metabolism , Biodegradation, Environmental
4.
Scand J Gastroenterol ; 37(6): 699-704, 2002 Jun.
Article in English | MEDLINE | ID: mdl-12126249

ABSTRACT

BACKGROUND: Inflammatory bowel disease (IBD) is a multifactorial disease with a significant genetic background. Evidence is accumulating that molecules such as CD14, which interact with luminal bacterial constituents, are involved in the pathogenesis. It has recently been shown that the T allele of the 5'-flanking region of the CD14 gene at position -159 is related to high expression of CD14. In further exploring the genetic background of IBD, we investigated this novel polymorphism of CD14 gene in patients with ulcerative colitis or Crohn disease. METHODS: DNA was obtained from 101 patients with ulcerative colitis, 82 with Crohn disease and 123 healthy controls. All were typed for the promoter polymorphism of the CD14 gene at position -159 by restriction fragment length polymorphism analysis. Serum samples were obtained from 105 healthy controls and serum sCD14 levels were measured. RESULTS: T allele frequencies were 57.4%, 48.2% and 44.7% in ulcerative colitis, Crohn disease and healthy controls, respectively. The T allele and T/T genotype frequencies were significantly higher in ulcerative colitis patients than in healthy controls (P = 0.0074, OR = 1.67, 95% CI = 1.15-2.42, P = 0.022, OR= 1.96 95% CI: 1.10-3.48, respectively). The sCD14 level was significantly higher in TT genotype populations than CC (P = 0.0205). CONCLUSIONS: The promoter polymorphism of the CD14 gene at -159T plays a significant role in regulating the CD14 expression and is positively associated with ulcerative colitis, and this polymorphism may confer a genetic predisposition to ulcerative colitis. The results also support the concept that bacterial constituents may be involved in the pathogenesis of ulcerative colitis.


Subject(s)
Colitis, Ulcerative/genetics , Crohn Disease/genetics , Genetic Predisposition to Disease , Lipopolysaccharide Receptors/genetics , Polymorphism, Genetic , Promoter Regions, Genetic , Adult , Aged , Base Sequence , Case-Control Studies , Colitis, Ulcerative/blood , Confidence Intervals , Crohn Disease/blood , Female , Gene Expression , Genotype , Humans , Male , Middle Aged , Molecular Sequence Data , Polymerase Chain Reaction , Probability , Reference Values , Sensitivity and Specificity
5.
Masui ; 48(4): 386-9, 1999 Apr.
Article in Japanese | MEDLINE | ID: mdl-10339937

ABSTRACT

We exchanged the tracheal T-tube inserted to a 17-year-old female, who wanted to be able to enunciate again, with relapsing polychondritis and difficulty in enunciation which the proximal end of tracheal T-tube above the false vocal cords was causing. The procedure was performed using Patil-Syracuse mask, without tracheal intubation, under-general anesthesia. This method will ensure precise length adjustment and correct placement of the T-tube under fiberoptic bronchoscope.


Subject(s)
Anesthesia, General , Intubation, Intratracheal/methods , Laryngeal Masks , Adolescent , Bronchoscopy , Female , Humans , Intubation, Intratracheal/instrumentation , Osteochondritis/complications , Recurrence , Tracheal Stenosis/etiology , Tracheal Stenosis/therapy
6.
Bioorg Med Chem Lett ; 8(9): 1019-22, 1998 May 05.
Article in English | MEDLINE | ID: mdl-9871700

ABSTRACT

New inhibitors have been designed for cdc2 kinase based on a multiple pseudosubstrate structure. The new inhibitors have three different structural components: 3,4-bis(indol-3-yl)maleimide, Ac-Cys-(Ser)-Pro-Lys-Lys-NHMe, and ethyloxy group between the two components. Inhibitory activities toward cdc2 and other protein kinases were investigated, and the compound (21) with Ac-Cys-Pro-Lys-Lys-NHMe connected with the triethylene glycol spacer exhibited the most potent inhibition with relatively high selectivity.


Subject(s)
CDC2 Protein Kinase/antagonists & inhibitors , Enzyme Inhibitors/chemical synthesis , Oligopeptides/chemical synthesis , Protein Kinase Inhibitors , Binding Sites , CDC2 Protein Kinase/chemistry , CDC2 Protein Kinase/metabolism , Catalytic Domain , Cyclin B/metabolism , Drug Design , Enzyme Inhibitors/chemistry , Enzyme Inhibitors/pharmacology , Histones/metabolism , Humans , Indicators and Reagents , Kinetics , Models, Molecular , Oligopeptides/chemistry , Oligopeptides/metabolism , Oligopeptides/pharmacology , Phosphorylation , Structure-Activity Relationship , Substrate Specificity
7.
Endocrinology ; 138(1): 356-61, 1997 Jan.
Article in English | MEDLINE | ID: mdl-8977424

ABSTRACT

Hair-follicle regression in the bald scalps of stumptailed macaques develops after puberty, which corresponds to an elevation of serum testosterone and dihydrotestosterone. Using the cultured cells from the pre- and postpubertal macaques, we examined the role of dermal papilla cells in testosterone-induced inhibition of outer root sheath cell proliferation. Testosterone showed no effects on proliferation of either dermal papilla cells or outer root sheath cells cultured alone. Testosterone-induced inhibition of outer root sheath cell proliferation occurred only in coculture with dermal papilla cells derived from the bald scalps of adult macaques but not with dermal papilla cells from the hairy occipital scalps of adult macaques or the prebald frontal scalps of juvenile macaques. Furthermore, RU 58841, an androgen receptor blocker, antagonized this testosterone-elicited inhibition. Together our data indicate that the inhibitory effect of testosterone on proliferation of epithelial cells is age dependent, and androgen may play an essential role in hair growth either by inducing repressor(s) from dermal papilla cells, which may then inhibit the growth of epithelial cells of the hair follicle, or by inducing growth factor(s) from dermal papilla cells, which, in turn, may trigger the induction of some repressors in epithelial cells, thereby inhibiting the epithelial cell growth. Our animal studies also showed that RU 58841 has a dramatic effect on hair regrowth in the bald frontal scalp of the stumptailed macaque, which may further support our in vitro culture studies showing that antiandrogens can antagonize testosterone-elicited hair growth. In summary, our studies may provide a model for further isolation of androgen-regulated repressor(s)/growth factors, which may help control hair growth and baldness.


Subject(s)
Alopecia/physiopathology , Hair/growth & development , Skin/cytology , Testosterone/pharmacology , Animals , Cell Division/drug effects , Cells, Cultured , Female , Hair/drug effects , Imidazoles/pharmacology , Macaca , Male , Nitriles/pharmacology
8.
J Dermatol Sci ; 13(1): 83-6, 1996 Oct.
Article in English | MEDLINE | ID: mdl-8902658

ABSTRACT

Immature hair apparatus cells were cultured for 3 days to allow to proliferate and differentiate into several subpopulations including hair-shaft type cells on day 6. Zymographic and immunocytochemical studies of the culture media were performed to examine whether the differentiated and/or immature cells from the murine hair apparatus can secrete type IV collagenases. Zymography showed the presence of 72 and 92 kDa type IV collagenases in media, in which hair apparatus cells had been cultured for 3 and 6 days. Most of the cells cultured for 3 and 6 days showed positive reactions with the mouse anti-gelatinase monoclonal antibody in the perinuclear cytoplasm. These data suggest that the differentiated cells as well as immature cells in the hair apparatus may retain the ability to produce and secrete 72 and 92 kDa collagenases.


Subject(s)
Collagenases/biosynthesis , Gelatinases/biosynthesis , Hair Follicle/cytology , Hair Follicle/enzymology , Metalloendopeptidases/biosynthesis , Animals , Cell Differentiation , Cell Division , Cells, Cultured , Collagenases/chemistry , Collagenases/metabolism , Gelatinases/chemistry , Gelatinases/metabolism , Matrix Metalloproteinase 2 , Matrix Metalloproteinase 9 , Metalloendopeptidases/chemistry , Metalloendopeptidases/metabolism , Mice , Molecular Weight
9.
J Dermatol ; 22(3): 171-4, 1995 Mar.
Article in English | MEDLINE | ID: mdl-7537768

ABSTRACT

In immunocytochemical studies of cultured hair apparatus cells we employed anti-hair keratin monoclonal antibodies (HKN-2, HKN-4, HKN-5, HKN-6 and HKN-7) and compared the results with electron microscopic studies. On day 1, the cultured cells positively stained with HKN-2 (52%), HKN-4 (50%), HKN-5 (43%), HKN-6 (33%), or HKN-7 (37%). On day 3, more than 88% of the cells showed no reaction to any antibody. On day 6, most of the cells stained with all of the antibodies: HKN-2 (96%), HKN-4 (92%), HKN-5 (80%), HKN-6 (72%) and HKN-7 (74%). These reactivities were maintained until day 13. Electron microscopic studies revealed that, on day 1, half of the observed cells were immature and 47% of them were already differentiated. Most (88%) of the cells showed immature features and the percentage of differentiated cells had decreased by day 3. The differentiated cells (87%) reappeared by day 6, and degenerated cells (63%) increased by day 13. These immunocytochemical results were consistent with those of simultaneous electron microscopic studies, demonstrating that immature cells proliferated and differentiated into subpopulations of each hair apparatus layer type, including the outer root sheath cells, in this culture system.


Subject(s)
Hair/chemistry , Animals , Antibodies, Monoclonal , Cells, Cultured , Hair/ultrastructure , Immunohistochemistry , Keratins/analysis , Mice , Mice, Inbred C3H
10.
Arch Dermatol Res ; 286(8): 484-9, 1994.
Article in English | MEDLINE | ID: mdl-7532390

ABSTRACT

The effects of acidic and basic fibroblast growth factors (aFGF and bFGF, respectively) on proliferation and differentiation of cultured hair apparatus cells were examined using bovine pituitary extract (BPE)-free media. The importance of FGFs as growth factors in BPE was also examined. Both FGFs and BPE stimulated cell proliferation and induced cell differentiation into several subpopulations corresponding to those of in vivo cell layers of the hair apparatus. Heparin enhanced the mitogenic activity of aFGF, but it did no affect that of bFGF. Heparin also partially inhibited or postponed the occurrence of cell differentiation induced by aFGF. Both aFGF- and bFGF-like proteins were detected in BPE by Western immunoblotting. BPE treated with anti-aFGF and/or anti-bFGF antibodies retained a significant mitogenic activity, although the mitogenic activities of FGFs were inhibited by their own specific antibodies. These results suggest that growth factors other than FGFs for cultured hair apparatus cells exist in BPE, although FGFs might substitute for BPE in this culture system as they stimulated cell proliferation and induced cell differentiation.


Subject(s)
Fibroblast Growth Factor 1/pharmacology , Fibroblast Growth Factor 2/pharmacology , Hair/cytology , Pituitary Gland/physiology , Animals , Cattle , Cell Differentiation/drug effects , Cell Division/drug effects , Cells, Cultured , Hair/drug effects , Heparin/pharmacology , Mice , Mice, Inbred C3H , Tissue Extracts/pharmacology
11.
Chem Pharm Bull (Tokyo) ; 41(2): 296-300, 1993 Feb.
Article in English | MEDLINE | ID: mdl-8500197

ABSTRACT

New fluorinated ligands with N-[(1-ethyl-2-pyrrolidinyl)methyl]-2,3-dihydrobenzofuran-7-carboxamide skeleton, which are useful as a prototype to develop 18F labelled in vivo radiotracer for positron emission tomography (PET), were synthesized, and their binding affinities for the dopamine D2 receptors were investigated. Fluorine atom was introduced at C-4 of the pyrrolidine ring (10) or at ethyl substituent at C-5 of the dihydrobenzofuran moiety (20). The in vitro IC50 values of these ligands for the dopamine D2 receptors which were determined by their ability to inhibit the binding of [3H]spiperone binding in rat striatal membrane were 17 and 36 nM, respectively. Thus, the fluorinated compounds 10 and 20 may be possible candidates for further in vivo investigation.


Subject(s)
Benzofurans/chemical synthesis , Dopamine/metabolism , Receptors, Dopamine D2/metabolism , Animals , Benzofurans/chemistry , Benzofurans/metabolism , Binding Sites , Corpus Striatum/metabolism , Dopamine/chemistry , Fluorine , In Vitro Techniques , Rats , Spiperone/metabolism , Structure-Activity Relationship , Tomography, Emission-Computed
12.
J Dermatol ; 19(11): 793-6, 1992 Nov.
Article in English | MEDLINE | ID: mdl-1284073

ABSTRACT

Human hair follicles were isolated from the scalp by dispase and collagenase treatment and dispersed into a cell suspension by trypsin. These cells proliferated well and could be subcultured 7 to 8 times. The medium used was MCDB 153 HAA medium further supplemented with some amino acids, hydrocortisone, insulin, EGF, and bovine brain extract. The concentration of Ca++ was adjusted to 0.1 mM. Immunohistochemically, these cells were proved to possess keratins specific to hair forming cells.


Subject(s)
Hair/chemistry , Keratins/analysis , Culture Techniques , Hair/cytology , Humans , Immunohistochemistry
13.
Arch Dermatol Res ; 284(5): 290-6, 1992.
Article in English | MEDLINE | ID: mdl-1444578

ABSTRACT

The effects of cepharanthine and minoxidil on proliferation, differentiation and keratinization of cultured cells from the murine hair apparatus were examined electron microscopically. Both cepharanthine and minoxidil stimulated cell proliferation and delayed initiation of differentiation and keratinization of the cultured cells. On day 6, most control cells (87%) cultured in a 0.03 mM calcium medium without cepharanthine and minoxidil were differentiated into several subpopulations corresponding to those of in vivo cell layers of the hair apparatus, while most of the cells cultured with cepharanthine (71%) or minoxidil (70%) were still immature. On day 13, the number of degenerated cells increased (63%) in the control culture, whereas in the culture treated with cepharanthine or minoxidil, cell degeneration scarcely occurred (5% and 8%, respectively). Differentiated cells having tonofilaments were often observed in the cepharanthine- and minoxidil-treated cultures (76% and 72%, respectively). Elevation of extracellular calcium up to 1.0 mM induced keratinization (34%) in the control culture on day 6, while no keratinized cells were observed in the cepharanthine- or minoxidil-treated culture. On day 13 keratinization similarly occurred in the cultures with cepharanthine (30%) or minoxidil (48%). These results show that both cepharanthine and minoxidil may directly influence proliferation, differentiation and keratinization of cultured cells from the hair apparatus.


Subject(s)
Alkaloids/pharmacology , Hair/drug effects , Minoxidil/pharmacology , Animals , Benzylisoquinolines , Cell Differentiation/drug effects , Cell Division/drug effects , Cells, Cultured , Hair/cytology , Hair/ultrastructure , Mice , Mice, Inbred C3H
14.
J Toxicol Sci ; 9(2): 131-42, 1984 May.
Article in English | MEDLINE | ID: mdl-6481823

ABSTRACT

Oral or intravenous administration of allethrin, a synthetic derivative of the pirethrin-based insecticides, produces neurotoxic symptoms consisting of mild salivation, hyperexcitability, tremors and convulsions which result in death. Intracerebroventricular injection of allethrin to mouse at about one-nineth the dose of intravenous administration, produced qualitatively identical but less prominent symptoms, indicating that at least some of the symptoms may be originated in the central nervous system. To investigate the mechanism of action of the compound, we studied the ability of agents which alter neurotransmission to prevent or potentiate the effect of convulsive doses of technical grade (15.5% cis, 84.5% trans) allethrin. Intraperitoneal pretreatment with drugs which block noradrenergic receptors or norepinephrine synthesis, such as pentobarbital, chlorpromazine, phentolamine, phenoxybenzamine and reserpine, depressed the tremor induced by allethrin. The inhibitory effect of reserpine was reversed by phenylephrine. Both the serotonergic blocker, methysergide, and the serotonin depletor, rho-chlorphenylalanine, potentiated the effect of allethrin. The potentiating effect of methysergide was antagonized by 5-hydroxytryptamine. However, intracerebroventricular administration of methysergide was ineffective in potentiating the effect of allethrin. alpha 2- and beta-adrenoceptor blockers, muscarinic antagonists, GABA mimenergics and morphine had no effect. These results suggest that allethrin produces its neurotoxic responses in mice by acting on the brain and spinal levels. Furthermore, adrenergic excitatory and serotonergic inhibitory mechanisms may be involved in the neural pathway through which the allethrin-induced tremor is evoked.


Subject(s)
Allethrins/toxicity , Serotonin/physiology , Sympathetic Nervous System/drug effects , Tremor/chemically induced , Animals , Electric Stimulation , Injections, Intraventricular , Male , Mice , Mice, Inbred Strains , Muscle Contraction/drug effects , Neuromuscular Junction/drug effects , Neurons/drug effects , Sympathetic Nervous System/physiopathology , Tremor/physiopathology
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