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1.
Lett Appl Microbiol ; 56(2): 128-34, 2013 Feb.
Article de Anglais | MEDLINE | ID: mdl-23121644

RÉSUMÉ

A PCR assay was developed to genotypically characterize Francisella tularensis and F. novicida. An integrated and partially redundant set of markers was selected to provide positive identification of these species, identify subspecies of F. tularensis and genotype 14 variable number tandem repeat (VNTR) markers. Assay performance was evaluated with 117 Francisella samples. Sample DNA was amplified, and the masses of the PCR products were determined with electrospray ionization/time of flight mass spectrometry (ESI-MS). The base compositions of the PCR amplicons were derived from these high-accuracy mass measurements and contrasted with databased information associated with each of the 25 assay markers. Species and subspecies determinations for all samples were fully concordant with results from established typing methods, and VNTR markers provided additional discrimination among samples. Sequence variants were observed with a number of assay markers, but these did not interfere with sample characterization, and served to increase the genetic diversity detected by the assay.


Sujet(s)
Techniques de typage bactérien/méthodes , Francisella tularensis/classification , Francisella tularensis/isolement et purification , Réaction de polymérisation en chaîne/méthodes , Animaux , Composition en bases nucléiques , ADN bactérien/génétique , Francisella tularensis/génétique , Marqueurs génétiques , Génotype , Répétitions minisatellites , Polymorphisme de nucléotide simple , Spécificité d'espèce , Spectrométrie de masse ESI , Tiques/microbiologie , Tularémie/génétique
2.
J Urol ; 154(4): 1566-70, 1995 Oct.
Article de Anglais | MEDLINE | ID: mdl-7658592

RÉSUMÉ

PURPOSE: To determine the effect of keratinocyte growth factor (KGF), a mesenchymally derived epithelial growth factor that can cause proliferation of pulmonary, gastrointestinal and mammary epithelia, on urothelium. MATERIALS AND METHODS: Recombinant human KGF was systemically administered to rats and Rhesus monkeys, and the proliferative effects on the bladder were evaluated. RESULTS: Keratinocyte growth factor causes proliferation of transitional epithelial cells. Proliferating cell nuclear antigen (PCNA) expression in rat bladder is dramatically increased along the basal layer of urothelium 1, 3, 7 and 14 days after daily injections of KGF. Incorporation of 5-bromodeoxyuridine (BrdU) at 7 and 14 days in the urothelium of KGF-treated rats parallels PCNA immunoreactivity and confirms that KGF increases DNA synthesis in urothelial cells. Urothelial cell proliferation is accompanied histologically by an increase in mitotic activity. Keratinocyte growth factor-induced PCNA expression is reversible upon cessation of KGF administration. Keratinocyte growth factor mRNA and receptor mRNA are detected by whole organ RNAase protection assays of the urinary bladder and the kidney of normal rats. Rhesus monkeys receiving KGF for 7 days demonstrate a dramatic incorporation of BrdU in the urothelium of the bladder and renal pelvis as well as in the collecting ducts of the kidney. CONCLUSION: Systemic administration of KGF causes rapid and striking proliferation of urothelium.


Sujet(s)
Facteurs de croissance fibroblastique , Substances de croissance/physiologie , Rein/cytologie , Vessie urinaire/cytologie , Animaux , Division cellulaire , Cellules épithéliales , Femelle , Facteur de croissance fibroblastique de type 10 , Facteur de croissance fibroblastique de type 7 , Substances de croissance/génétique , Macaca mulatta , Mâle , Antigène nucléaire de prolifération cellulaire/biosynthèse , ARN messager/biosynthèse , Rats , Rats de lignée LEW , Rat Sprague-Dawley , Récepteur facteur croissance/génétique
3.
Am J Pathol ; 145(5): 1015-22, 1994 Nov.
Article de Anglais | MEDLINE | ID: mdl-7977634

RÉSUMÉ

Keratinocyte growth factor (KGF) is a paracrine mediator of epithelial cell proliferation that has been reported to induce marked proliferation of mammary epithelium in rats. In this study, systemic administration of KGF into naive and oophorectomized mice causes mammary gland proliferation, as evidenced histologically by the appearance of cysts lined by a single layer of epithelium and by hyperplastic epithelium. Whole mount preparations of the mammary glands reveal that the histologically noted cysts are actually ducts that are dilated along much of their length. The histology of the mammary glands of KGF-treated mice is similar to the histology of fibrocystic disease in the human female breast. The response in mice differs significantly from the appearance of the mammary glands in KGF-treated rats in which ductal epithelial proliferation is most prominent. Estrogen and progesterone when administered in combination but not alone cause the development of numerous endbuds in the mouse mammary gland. KGF in estrogen- and progesterone-pretreated mice causes the growth of dilated ducts, hyperplastic epithelium within ducts and endbuds, and a fibrous metamorphosis of periductal adipose tissue. The mammary epithelial hyperplasia caused by KGF is rapidly reversible in both mice and rats after cessation of KGF treatment. The spectrum of KGF-, estrogen-, and progesterone-induced mammary histopathology in mice provides a model for the study of fibrocystic and hyperplastic breast disease.


Sujet(s)
Région mammaire/effets des médicaments et des substances chimiques , Oestrogènes/pharmacologie , Facteurs de croissance fibroblastique , Maladie fibrokystique du sein/anatomopathologie , Substances de croissance/pharmacologie , Progestérone/pharmacologie , Animaux , Région mammaire/anatomopathologie , Femelle , Facteur de croissance fibroblastique de type 10 , Facteur de croissance fibroblastique de type 7 , Maladie fibrokystique du sein/induit chimiquement , Hyperplasie , Souris , Souris de lignée BALB C , Ovariectomie , Protéines recombinantes/pharmacologie
4.
J Clin Invest ; 94(5): 1764-77, 1994 Nov.
Article de Anglais | MEDLINE | ID: mdl-7962522

RÉSUMÉ

Keratinocyte growth factor (KGF), a member of the fibroblast growth factor (FGF) family, was identified as a specific keratinocyte mitogen after isolation from a lung fibroblast line. Recently, recombinant (r)KGF was found to influence proliferation and differentiation patterns of multiple epithelial cell lineages within skin, lung, and the reproductive tract. In the present study, we designed experiments to identify additional target tissues, and focused on the rat gastrointestinal (GI) system, since a putative receptor, K-sam, was originally identified in a gastric carcinoma. Expression of KGF receptor and KGF mRNA was detected within the entire GI tract, suggesting the gut both synthesized and responded to KGF. Therefore, rKGF was administered to adult rats and was found to induce markedly increased proliferation of epithelial cells from the foregut to the colon, and of hepatocytes, one day after systemic treatment. Daily treatment resulted in the marked selective induction of mucin-producing cell lineages throughout the GI tract in a dose-dependent fashion. Other cell lineages were either unaffected (e.g., Paneth cells), or relatively decreased (e.g., parietal cells, enterocytes) in rKGF-treated rats. The direct effect of rKGF was confirmed by demonstrating markedly increased carcinoembryonic antigen production in a human colon carcinoma cell line, LIM1899. Serum levels of albumin were specifically and significantly elevated after daily treatment. These results demonstrate rKGF can induce epithelial cell activation throughout the GI tract and liver. Further, endogenous KGF may be a normal paracrine mediator of growth within the gut.


Sujet(s)
Système digestif/effets des médicaments et des substances chimiques , Facteurs de croissance fibroblastique , Substances de croissance/pharmacologie , Foie/effets des médicaments et des substances chimiques , Récepteur facteur croissance fibroblaste , Animaux , Antigène carcinoembryonnaire/analyse , Différenciation cellulaire/effets des médicaments et des substances chimiques , Division cellulaire/effets des médicaments et des substances chimiques , Tumeurs du côlon/immunologie , Système digestif/cytologie , Cellules épithéliales , Épithélium/effets des médicaments et des substances chimiques , Oesophage/cytologie , Oesophage/effets des médicaments et des substances chimiques , Facteur de croissance fibroblastique de type 10 , Facteur de croissance fibroblastique de type 7 , Histocytochimie , Humains , Foie/cytologie , Mâle , Rats , Rat Sprague-Dawley , Récepteur FGFR2 , Récepteur facteur croissance/génétique , Protéines recombinantes/pharmacologie , Cellules cancéreuses en culture
5.
Am J Pathol ; 145(1): 80-5, 1994 Jul.
Article de Anglais | MEDLINE | ID: mdl-7913296

RÉSUMÉ

Keratinocyte growth factor (KGF) causes a proliferation of pancreatic ductal epithelial cells in adult rats after daily systemic administration for 1 to 2 weeks. Even before the proliferation of intralobular ducts is histologically evident, KGF also induces proliferating cell nuclear antigen expression within the ductal epithelium of intercalated, intralobular, and interlobular ducts. KGF also causes incorporation of 5-bromodeoxyuridine in ductal epithelial cells. Epithelial cell proliferation is histologically most prominent at the level of the intralobular ducts adjacent to and within the islets of Langerhans. Pancreatic ductal proliferation is not histologically apparent in rats sacrificed 7 to 10 days after the cessation of KGF administration. The pancreatic hormones insulin, glucagon, somatostatin, and pancreatic polypeptide are normally distributed within islets that demonstrate intrainsular ductal proliferation. The proliferating ductal epithelium does not show endocrine differentiation as evidenced by the lack of immunoreactivity for pancreatic hormones. KGF is a potent in vivo mitogen for pancreatic ductal epithelial cells.


Sujet(s)
Facteurs de croissance fibroblastique , Substances de croissance/administration et posologie , Conduits pancréatiques/cytologie , Animaux , Broxuridine/administration et posologie , Broxuridine/métabolisme , Division cellulaire/effets des médicaments et des substances chimiques , Cellules épithéliales , Épithélium/effets des médicaments et des substances chimiques , Épithélium/métabolisme , Femelle , Facteur de croissance fibroblastique de type 10 , Facteur de croissance fibroblastique de type 7 , Injections péritoneales , Injections veineuses , Injections sous-cutanées , Mâle , Protéines nucléaires/métabolisme , Conduits pancréatiques/effets des médicaments et des substances chimiques , Conduits pancréatiques/métabolisme , Antigène nucléaire de prolifération cellulaire , Rats , Rats de lignée LEW , Facteurs temps
6.
J Clin Invest ; 93(3): 1298-306, 1994 Mar.
Article de Anglais | MEDLINE | ID: mdl-8132770

RÉSUMÉ

Keratinocyte growth factor (KGF) administered as a single intratracheal injection causes a prominent dose-dependent proliferation of type II alveolar epithelial cells in the lungs of adult rats. The increase in mitotically active alveolar cells histologically appears as a micropapillary epithelial cell hyperplasia after 2 d and peaks after 3 d in the form of monolayers of cuboidal epithelial cells lining alveolar septae. Proliferating cell nuclear antigen immunohistochemistry confirmed the profound proliferative response induced by KGF. The hyperplastic alveolar lining cells contain immunoreactive surfactant protein B and are ultrastructurally noted to contain lamellar inclusions characteristic of surfactant-producing type II pneumocytes. Mild focal bronchiolar epithelial hyperplasia is noted but is much less striking than the proliferation of type II pneumocytes. Large airways are unaffected by KGF. Daily intravenous injection of KGF is also able to cause pneumocyte proliferation. The normal adult rat lung constitutively expresses both KGF and KGF receptor mRNA, suggesting that endogenous KGF may be implicated in the paracrine regulation of the growth of pneumocytes. In conclusion, KGF rapidly and specifically induces proliferation and differentiation of type II pneumocytes in the normal adult lung.


Sujet(s)
Facteurs de croissance fibroblastique , Substances de croissance/pharmacologie , Poumon/effets des médicaments et des substances chimiques , Récepteur facteur croissance fibroblaste , Animaux , Division cellulaire/effets des médicaments et des substances chimiques , Relation dose-effet des médicaments , Facteur de croissance fibroblastique de type 10 , Facteur de croissance fibroblastique de type 7 , Substances de croissance/génétique , Hyperplasie , Poumon/cytologie , Mâle , ARN messager/analyse , Rats , Rats de lignée LEW , Rat Sprague-Dawley , Récepteur FGFR2 , Récepteur facteur croissance/génétique
7.
Science ; 254(5038): 1621-4, 1991 Dec 13.
Article de Anglais | MEDLINE | ID: mdl-17782213

RÉSUMÉ

The earliest pottery yet found in the Western Hemisphere has been excavated from a prehistoric shell midden near Santarém in the lower Amazon, Brazil. Calibrated accelerator radiocarbon dates on charcoal, shell, and pottery and a thermoluminescence date on pottery from the site fall from about 8000 to 7000 years before the present. The early fishing village is part of a long prehistoric trajectory that contradicts theories that resource poverty limited cultural evolution in the tropics.

8.
J Am Vet Med Assoc ; 196(7): 1139-40, 1990 Apr 01.
Article de Anglais | MEDLINE | ID: mdl-2329086

RÉSUMÉ

Ivermectin was used to treat ear mite infestation in 480 rabbits in 2 commercial rabbitries. Ivermectin (cattle formulation) injected sc at a dosage of 400 to 440 micrograms/kg of body weight repeated in 18 days appeared to be safe and effective in reducing the prevalence of ear mites in naturally infested rabbits.


Sujet(s)
Conduit auditif externe , Ivermectine/usage thérapeutique , Acarioses/médecine vétérinaire , Lapins/parasitologie , Animaux , Évaluation de médicament/médecine vétérinaire , Maladies des oreilles/traitement médicamenteux , Maladies des oreilles/médecine vétérinaire , Acarioses/traitement médicamenteux
11.
Comput Healthc ; 5(6): 56, 1984 Jun.
Article de Anglais | MEDLINE | ID: mdl-10266377
12.
Science ; 205(4411): 1082-3, 1979 Sep 14.
Article de Anglais | MEDLINE | ID: mdl-17735028
13.
Science ; 175(4021): 521-3, 1972 Feb 04.
Article de Anglais | MEDLINE | ID: mdl-17755653

RÉSUMÉ

Crystals of armalcolite, Mg(0.5)Fe(0.5)Ti(2)O(5), up to several millimeters in length have been grown from a glass initially having the composition of lunar rock 10017. A single-crystal x-ray study has confirmed that the crystals are isomorphous with pseudobrookite and has shown that the cations are strongly ordered, with the Ti(4+) ions occupying the 8f sites and the Fe(2+) and Mg(2+) ions randomly distributed over the 4c sites. An examination of karrooite, MgTi(2)O(5), has revealed a similar distribution of Mg(2+) and Ti(4+) ions. A reexamination of earlier x-ray and Mössbauer data for pseudobrookite, Fe(2)TiO(5), has shown that it is more consistent with this type of ordering than with the inverse structure that has been generally assumed.

14.
Science ; 167(3918): 688-90, 1970 Jan 30.
Article de Anglais | MEDLINE | ID: mdl-17781547

RÉSUMÉ

Lunar bulk sample 10084,85 (< 1 mm size dust), and samples from rocks 10017,17 (fine grained, vesicular), 10046,17 (breccia), 10057,59 (fine grained, vesicular, top surface), 10057,60 (fine grained, vesicular, interior), and 10058,24 (medium grained, not vesicular) have been investigated by (57)Fe Mössbauer spectroscopy. Iron metal and the Fe(2+) minerals ilmenite, pyroxene, troilite, and iron containing glass have been identified. An iron line of sample 10084,85 (originally sealed in nitrogen) showed no significant intensity change when the sample was exposed to air. The antiferromagnetic transition in several lunar ilmenites at 57(0) +/- 2 degrees K corresponds to stoichiometric FeTiO,. Magneticallv separated 10057 showed troilite and somne metallic iron.

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