142 resultados para Isolated solution


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Abstract In this study, matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) was used as a rapid method to identify yeasts isolated from patients in Tunisian hospitals. When identification could not be exstablished with this procedure, sequencing of the internal transcribed spacer with 5.8S ribosomal DNA (rDNA) (ITS1-5.8S-ITS2) and D1/D2 domain of large-subunit (LSU rDNA) were employed as a molecular approach for species differentiation. Candida albicans was the dominant species (43.37% of all cases), followed by C. glabrata (16.55%), C. parapsilosis (13.23%), C. tropicalis (11.34%), C. dubliniensis (4.96%), and other species more rarely encountered in human diseases such as C. krusei, C. metapsilosis, C. lusitaniae, C. kefyr, C. palmioleophila, C. guilliermondii, C. intermedia, C. orthopsilosis, and C. utilis. In addition, other yeast species were obtained including Saccharomyces cerevisiae, Debaryomyces hansenii (anamorph known as C. famata), Hanseniaspora opuntiae, Kodamaea ohmeri, Pichia caribbica (anamorph known as C. fermentati), Trichosporon spp. and finally a novel yeast species, C. tunisiensis. The in vitro antifungal activities of fluconazole and voriconazole were determined by the agar disk diffusion test and Etest, while the susceptibility to additional antifungal agents was determined with the Sensititre YeastOne system. Our results showed low incidence of azole resistance in C. albicans (0.54%), C. tropicalis (2.08%) and C. glabrata (4.28%). In addition, caspofungin was active against most isolates of the collection with the exception of two K. ohmeri isolates. This is the first report to describe caspofungin resistant isolates of this yeast.

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Oxidative metabolism of isolated toad skin epithelium (Bufo viridis) was investigated in vitro under open-circuit conditions using the spectrophotometric oxyhemoglobin micromethod. This highly sensitive technique has been adapted for studying several epithelia in parallel and for detecting possible regional variations of oxygen uptake in individual epithelium. Changes in the proportion of mitochondria-rich cells (MRC) by ionic acclimation affected oxidative metabolism under nontransporting condition. After acclimation of animals to either NaNO3 or NaCl solutions (100 mmol/l, for greater than 2 wk), the number of MRC per square millimeter in epithelia from nonacclimated and NaNO3- and NaCl-acclimated animals was 350 +/- 113, 460 +/- 196, and 107 +/- 52, respectively. O2 uptake of nonacclimated and NaNO3-acclimated epithelia was significantly higher than that of NaCl-acclimated epithelia (i.e., 0.89 and 0.90 vs. 0.57 nmol O2.h-1.mm-2, respectively). The correlation established between O2 uptake and number of MRC allowed evaluation of the respiration rate of one single MRC, i.e., approximately 1 pmol O2/h. The lowest mitochondrial oxidative activity was found in the epithelia from NaCl-acclimated toads where the uncoupler 2,4-dinitrophenol (50 mumols/l) had the highest relative stimulatory effect (+114%). Acetazolamide (50 mumols/l), a potent inhibitor of carbonic anhydrase mainly present in the MRC, reduced selectively by 31% O2 uptake of the MRC-rich epithelia (NaNO3 acclimated). O2 uptake increased significantly by approximately 80% when basolateral pH increased from 5.8 to 7.8, but did not depend on apical pH. These findings indicate that under nontransporting (open-circuit) conditions, aerobic metabolism of the isolated toad skin epithelium is related to the density and/or characteristics of the MRC.(ABSTRACT TRUNCATED AT 250 WORDS)

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Endothelium-derived nitric oxide (EDNO) plays a pivotal role in regulating pulmonary circulation. To determine whether there is a heterogeneity in EDNO-mediated responses of different sized pulmonary vessels, we studied small and large isolated pulmonary arteries of newborn lambs (diameter, 0.4-0.7 and 1.5-2.5 mm, respectively). The isometric tension of vessel rings were recorded while suspended in organ chambers filled with modified Krebs-Ringer bicarbonate solution (95% O2-5% CO2, 37 degrees C). In vessels preconstricted with norepinephrine, acetylcholine and bradykinin induced a greater relaxation of small pulmonary arteries than of large pulmonary arteries. Acetylcholine, bradykinin, and nitric oxide also induced a greater increase in cGMP content in small arteries than in large ones. The responses to acetylcholine and bradykinin were endothelium-dependent and inhibited by nitro-L-arginine, an inhibitor of nitric oxide synthase. In vessels without endothelium, the response to nitric oxide was inhibited by 1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one, an inhibitor of soluble guanylate cyclase. The activity of soluble guanylyl cyclase of small arteries was greater than that of large arteries under basal conditions and after stimulation with S-nitroso-N-acetylpenicillamine, a nitric oxide donor. These results demonstrate that heterogeneity exists in EDNO-mediated relaxation of small and large pulmonary arteries in newborn lambs. A difference in the soluble guanylate cyclase activity of vascular smooth muscle may have contributed to this phenomenon.

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Background: Isolated complex III deficiencies are caused by mutations in the mitochondrial CytB gene, in the BCS1L gene coding for a CIII assembly factor and in the UQCRQ gene that codes for the ubiquinone binding protein of complex III. Objective: Description of clinical features, mitochondrial function and molecular genetic analysis in a patient with an isolated complex III deficiency. Patient: A 17 year old boy, born to consanguineous parents who presented with hypoglycemia, glycosuria, deafness, growth retardation, Fanconi Syndrome and severe lactic acidosis in the neonatal period. Methods: Activities and assembly of OXPHOS complexes were investigated spectrophotometrically and by BN-PAGE. mt-DNAwas screened for deletions. Cytochrome b (CytB) and the BCS1L gene were sequenced. Results: Isolated complex III deficiency was detected in the patient's skeletal muscle. Using BN-PAGE blotting a complex III of lower molecular weight was detected. Staining the 2D reveals a missing subunit. No mutation was detected in the mitochondrial CytB gene. Sequence analysis of BCS1L revealed a novel homozygous point mutation p.M48V. Conclusion: The patients decreased complex III activity is most likely caused by incomplete assembly of complex III due to the homozygous p. M48V mutation in the BCS1L gene.

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Using a direct binding assay based on photoaffinity labeling, we have studied the interaction of antigenic peptides with murine MHC class I molecules on living cells. Photoreactive derivatives were prepared by N-terminal amidation with iodo, 4-azido salicylic acid of the Kd restricted Plasmodium berghei circumsporozoite (P.b. CS) peptide 253-260 (YIPSAEKI) and the Db-restricted Adenovirus 5 early region 1A (Ad5 E1A) peptide 234-243 (SGPSNTPPEI). As assessed in functional competition experiments, both peptide derivatives retained the specific binding activity of the parental peptides for Kd or Dd, respectively. The P.b. CS photoprobe specifically labeled Kd molecules on P815 (H-2d) cells, but failed to label RMA (H-2b) cells. Conversely, the Ad5 E1A photoprobe specifically labeled Db molecules on RMA cells, but failed to label P815 cells. When the two photoprobes were tested on a panel of Con A-activated spleen cells expressing 10 different H-2 haplotypes, significant photoaffinity labeling was observed only on H-2d cells with the P.b. CS photoprobe and on H-2b cells with the Ad5 E1A photoprobe. Labeling of cell-associated Kd or Db molecules with the photoprobes was specifically inhibited by antigenic peptides known to be presented by the same class I molecule. Photoaffinity labeling of Kd with the P.b. CS photoprobe was used to study the dynamics of peptide binding on living P815 cells. Binding increased steadily with the incubation period (up to 8 h) at 37 degrees C and at ambient temperature, but was greatly reduced (greater than 95%) at 0 to 4 degrees C or in the presence of ATP synthesis inhibitors. The magnitude of the labeling was twofold higher at room temperature than at 37 degrees C. In contrast, binding to isolated Kd molecules in solution rapidly reached maximal binding, particularly at 37 degrees C. Dissociation of the photoprobe from either cell-associated or soluble Kd molecules was similar, with a half time of approximately 1 h at 37 degrees C, whereas the complexes were long-lived at 4 degrees C in both instances.

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Slightly displaced clavicular midshaft fracture is currently treated nonoperatively. There is considerable debate about whether acute displaced fractures should be treated operatively. Nonunion rate after displaced fracture has been underestimated for a long time, and malunion clinical impact often minimized. It is known that operative treatment decreases these rates. However, operating all displaced fractures may lead to overtreatment. Acute operative treatment of midshaft fractures with delayed treatment of established nonunion showed no significant difference in the outcome, but malunion surgical management is technically demanding. Consequently these fractures could be treated surgically, but operative indication should be adapted to patient expectations.

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BACKGROUND: Ethiopia ranks seventh in the list of 22 high tuberculosis (TB) burden countries, with an incidence rate of 379 cases per 100 000 population for TB all forms. However, information on the genomic diversity of Mycobacterium tuberculosis in Ethiopia is limited. OBJECTIVE: To investigate the molecular characteristics of M. tuberculosis strains implicated in pulmonary TB in the study area. METHODS AND RESULTS: A cross-sectional study was conducted using socio-demographic, clinical and culture data combined with molecular typing analysis. The proportion of TB and M. tuberculosis isolates was not associated with risk factors (P > 0.05). Of 99 sputum samples, 80.8% were culture-positive. Speciation of isolates showed that 88.8% were M. tuberculosis. Further characterisation led to the identification of 27 different spoligotype patterns of M. tuberculosis; the most dominant shared types were SIT149, SIT53 and SIT54. Of the 27 strains, three strains were new and were reported to the SITVIT database. More than two thirds of the strains belonged to the Euro-American lineage. CONCLUSION: This study shows the presence of several clusters and new strains of M. tuberculosis circulating in pulmonary TB patients in the study area, suggesting recent transmission. Nationwide studies are recommended to map the population structure of M. tuberculosis and set control measures.

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Introduction: Enchondromas are among the most current benign bone tumours. Malignant degeneration is extremely rare (<1%) and generally presents as a low grade chondrosarcoma. For localized grade 1 lesions, the treatment of choice is curettage. Wide excision and reconstruction is generally not necessary, unless locally advanced or more aggressive behaviour is suspected at presentation. Case report: A healthy 72 yo male presented with pain and recurrent knee joint effusion. X-rays show a classical central distal metaphyseal enchondroma of the femur associated with subtle osteolysis of the lateral condyle. MRI confirms the presence of a locally aggressive chondromatous lesion based in a classical enchondroma. Core needle biopsy revealed a grade 1 chondrosarcoma, which was in contrast to the radiological aggressiveness of the lesion. Total body CT-scan did not reveal metastatic disease. A wide resection was planned, as a high-grade lesion and joint contamination was suspected. We performed an extra-articular knee resection and reconstruction with a hinged modular total knee megaprosthesis. The definitive histology was grade 1 chondrosarcoma, the surgical margins were wide. The evolution was favourable and the patient was able to perform all his activities of daily living independently without pain at 6 weeks postop. Knee flexion reached 90°. The oncologic screening at 18 months did not show local or distant recurrence. Conclusion: Joints near a benign tumour that suddenly become symptomatic or present an effusion might indicate a malignant transformation. Wide resection and prosthetic reconstruction remains an effective treatment option even in low grade cartilaginous lesions if (1) the adjacent joint is contaminated, or (2) joint-sparing surgery would result in a severe functional impairment of the limb.

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During ODP Leg 123, abundant and well-preserved Neocomian radiolarians were recovered at Site 765 (Argo Abyssal Plain) and Site 766 (lower Exmouth Plateau). Assemblages are characterized by the numerical dominance of a small number of non-tethyan forms and by the scarcity of tethyan taxa. Remarkable contrasts exist between radiolarian assemblages extracted from claystones of Site 765 and reexamined DSDP Site 26 1, and faunas recovered from radiolarian sand layers, only found at Site 765. Clay faunas are unusual in their low diversity of apparently ecologically tolerant (or solution resistant?), ubiquist species, whereas sand faunas are dominated by non-tethyan taxa. Comparisons with Sites 766 and 26 1, as well as sedimentological observations, lead to the conclusion that this faunal contrast resulted from a difference in provenance, rather than from hydraulic sorting or selective dissolution. The ranges of 27 tethyan taxa from Site 765 were compared to the tethyan radiolarian zonation by Jud (1992) by means of the Unitary Associations Method. This calculation allows to directly date the Site 765 assemblages and to estimate the amount of truncation of ranges for tethyan taxa. Over 70% of the already few tethyan species of Site 765, have truncated ranges during the Valanginian-Hauterivian. Radiolarian assemblages recovered from claystones at Sites 765 and 261 in the Argo Basin apparently reflect restricted oceanic conditions during the latest Jurassic-Barremian. Neither sedimentary facies nor faunal associations bear any resemblance to what we know from typical tethyan sequences. We conclude that the Argo Basin was paleoceanographically separated from the Tethys during the Late Jurassic and part of the Early Cretaceous by its position at higher paleolatitudes and/or by enclosing land masses. Assemblages recovered from radiolarian sand layers are dominated by non-tethyan species that are interpreted as circumantarctic. Their first appearance in the late Berriasian-early Valanginian predates the oceanization of the Indo-Australian breakup (M11, late Valanginian), but coincides with a sharp increase in margin-derived pelagic turbidites. The Indo-Australian rift zone and the adjacent margins must have been submerged deeply enough to allow an intermittent influx of circumantarctic cold water into the Argo Basin, creating increased bottom current activity. Cold-water radiolarians carried into the Argo Basin upwelled along the margin, died, and accumulated in radiolarite layers due to winnowing by bottom currents. High rates of faunal change and the sharp increase of bottom current activity are thought to be synchronous with possible pronounced late Berriasian-early Valanginian lowstands in sea level. Hypothetically, both phenomena might have been.caused by a tendency to glaciation on the Antarctic-Australian continent, which was for the first time isolated from the rest of Gondwana by oceanic seaways as a result of Jurassic-Early Cretaceous sea-floor spreading. The absence of most typical tethyan radiolarian species during the Valanginian-Hauterivian is interpreted as reflecting a time of strong influx of circumantarctic cold water following oceanization (M11) and rapid spreading between Southeast India and West Australia. The reappearance and gradual abundance/diversity increase of tethyan taxa, along with the still dominant circumantarctic species are thought to result from overall more equitable climatic conditions during the Barremian-early Aptian and from the establishment of an oceanic connection with the Tethys Ocean during the early Aptian.

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Rapport de synthèseDrug uptake in a rodent sarcoma model after intravenous injection or isolated lungperfusion of free/liposomal doxorubicinIntroductionLa distribution de doxorubicine libre et doxorubicin liposomale pegylée (Liporubicin?) a été comparée après administration intraveineuse ou application via perfusion isolée du poumon (ILP) dans le parenchyme pulmonaire et dans la tumeur des poumons de rongeurs, porteurs d'une tumeur sarcomateuse.Matériel et méthodeUne tumeur sarcomateuse unique a été générée dans le poumon gauche de 36 rongeurs (Fisher rats) suivie, 10 jours plus tard, par application de doxorubicine ou Liporubicin? soit par perfusion isolée du poumon (n = 20) ou administration intraveineuse (n = 12). Deux différentes concentrations ont été utilisées (100 μg et 400 pg) à doses équimolaires pour les deux formulations de doxorubicine. La concentration des agents cytostatiques ont été mesurées dans la tumeur et le parenchyme pulmonaire à l'aide de chromatographic (HPLC).RésultatsLes résultats indiquent que pour doxorubicine libre, le taux de concentration dans la tumeur et le parenchyme pulmonaire est 3 fois (dosage de 100 μ§) et 10 fois (dosage de 400 plus élevé après ILP par rapport à l'administration intraveineuse. En revanche, pour Liporubicin , le taux de concentration est similaire dans la tumeur et le parenchyme pulmonaire entre ILP et administration intraveineuse, pour les deux doses appliquées.ConclusionPour ILP et administration intraveineuse, le ratio entre accumulation de l'agent cytostatique dans la tumeur versus dans le parenchyme pulmonaire a été comparé pour les deux formulations de doxorubicine ainsi que pour les deux dosages. Pour les deux formulations et dosages de doxorubicine, ILP aboutit à un ratio plus élevé par rapport à l'administration intraveineuse. Cependant, pour les deux formulations et dosages de doxorubicine, ILP résulte également en une distribution de l'agent cytostatique plus hétérogène dans le parenchyme pulmonaire comparé à l'administration intraveineuse.En résumé, l'application de doxorubicine par ILP aboutit donc à une accumulation tumorale élevée et à une augmentation du ratio tumeur-parenchyme pulmonaire, mais en même temps également à une distribution plus hétérogène dans le parenchyme pulmonaire par rapport à l'application intraveineuse. Ceci a été observé pour les deux formulations de doxorubicine et pour les deux dosages appliqué.

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Background: Negative pressure wound treatment is increasingly used through a Vacuum-Assisted Closure (VAC) device in complex wound situations. For this purpose, sterile polyurethane (PU) and polyvinyl alcohol (PVA) foam dressings are fitted to the wound size and covered with an adhesive drape to create an airtight seal. Little information exists about the type and quantity of microorganisms within the foams. Therefore, we investigated VAC foams after removal from the wound using a validated method (sonication) to detect the bacterial bioburden in the foam consisting as microbial biofilms.Methods: We prospectively included VAC foams (PU and PVA, KCI, Rümlamg, Switzerland) without antibacterial additions (e.g. silver), which were removed from wounds in patients with chronic ulcers from January 2007 through December 2008. Excluded were patients with acute wound infection, necrotizing fasciitis, underlying osteomyelitis or implant. Removed foams from regular changes of dressing were aseptically placed in a container with 100 ml sterile Ringer's solution. Within 4 hours after removal, foams were sonicated for 5 min at 40 kHz (as described in NEJM 2007;357:654). The resulting sonication fluid was cultured at 37°C on aerobic blood agar plates for 5 days. Microbes were quantified as No. of colony-forming units (CFU)/ml sonication fluid and identified to the species level.Results: A total of 68 foams (38 PU and 30 PVA) from 55 patients were included in the study (median age 71 years; range 33-88 years, 57% were man). Foams were removed from the following anatomic sites: sacrum (n=29), ischium (n=18), heel (n=13), calves (n=6) and ankle (n=2). The median duration of being in place was 3 days (range, 1-8 days). In all 68 foams, bacteria were found in large quantities (median 105 CFU/ml, range 102-7 CFU/ml sonication fluid. No differences were found between PU and PVA foams. One type of organisms was found in 11 (16%), two in 17 (24%) and 3 or more in 40 (60%) foams. Gram-negative rods (Escherichia coli, Proteus mirabilis, Klebsiella pneumoniae, Acinetobacter baumanii, Pseudomonas aeruginosa) were isolated in 70%, followed by Staphylococcus aureus (20%), koagulase-negative staphylococci, streptococci (8%), and enterococci (2%).Conclusion: With sonication, a high density of bacteria present in VAC foams was demonstrated after a median of 3 days. Future studies are needed to investigate whether antimicrobial-impregnated foams can reduce the bacterial load in foams and potentially improve wound healing.

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GLUT2 expression is strongly decreased in glucose-unresponsive pancreatic beta cells of diabetic rodents. This decreased expression is due to circulating factors distinct from insulin or glucose. Here we evaluated the effect of palmitic acid and the synthetic glucocorticoid dexamethasone on GLUT2 expression by in vitro cultured rat pancreatic islets. Palmitic acid induced a 40% decrease in GLUT2 mRNA levels with, however, no consistent effect on protein expression. Dexamethasone, in contrast, had no effect on GLUT2 mRNA, but decreased GLUT2 protein by about 65%. The effect of dexamethasone was more pronounced at high glucose concentrations and was inhibited by the glucocorticoid antagonist RU-486. Biosynthetic labeling experiments revealed that GLUT2 translation rate was only minimally affected by dexamethasone, but that its half-life was decreased by 50%, indicating that glucocorticoids activated a posttranslational degradation mechanism. This degradation mechanism was not affecting all membrane proteins, since the alpha subunit of the Na+/K+-ATPase was unaffected. Glucose-induced insulin secretion was strongly decreased by treatment with palmitic acid and/or dexamethasone. The insulin content was decreased ( approximately 55 percent) in the presence of palmitic acid, but increased ( approximately 180%) in the presence of dexamethasone. We conclude that a combination of elevated fatty acids and glucocorticoids can induce two common features observed in diabetic beta cells, decreased GLUT2 expression, and loss of glucose-induced insulin secretion.

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AIMS: To assess the impact of the biocontrol strain Pseudomonas fluorescens CHA0 on a collection of barley rhizosphere bacteria using an agar plate inhibition assay and a plant microcosm, focusing on a CHA0-sensitive member of the Cytophaga-like bacteria (CLB). METHODS AND RESULTS: The effect of strain CHA0 on a collection of barley rhizosphere bacteria, in particular CLB and fluorescent pseudomonads sampled during a growth season, was assessed by a growth inhibition assay. On average, 85% of the bacteria were sensitive in the May sample, while the effect was reduced to around 68% in the July and August samples. In the May sample, around 95% of the CLB and around 45% of the fluorescent pseudomonads were sensitive to strain CHA0. The proportion of CHA0-sensitive CLB and fluorescent pseudomonad isolates decreased during the plant growth season, i.e. in the July and August samples. A particularly sensitive CLB isolate, CLB23, was selected, exposed to strain CHA0 (wild type) and its genetically modified derivatives in the rhizosphere of barley grown in gnotobiotic soil microcosms. Two dry-stress periods were imposed during the experiment. Derivatives of strain CHA0 included antibiotic or exopolysaccharide (EPS) overproducing strains and a dry-stress-sensitive mutant. Despite their inhibitory activity against CLB23 in vitro, neither wild-type strain CHA0, nor any of its derivatives, had a major effect on culturable and total cell numbers of CLB23 during the 23-day microcosm experiment. Populations of all inoculants declined during the two dry-stress periods, with soil water contents below 5% and plants reaching the wilting point, but they recovered after re-wetting the soil. Survival of the dry-stress-sensitive mutant of CHA0 was most affected by the dry periods; however, this did not result in an increased population density of CLB23. CONCLUSIONS: CLB comprise a large fraction of barley rhizosphere bacteria that are sensitive to the biocontrol pseudomonad CHA0 in vitro. However, in plant microcosm experiments with varying soil humidity conditions, CHA0 or its derivatives had no major impact on the survival of the highly sensitive CLB strain, CLB23, during two dry-stress periods and a re-wetting period; all co-existed well in the rhizosphere of barley plants. SIGNIFICANCE AND IMPACT OF THE STUDY: Results indicate a lack of interaction between the biocontrol pseudomonad CHA0 and a sensitive CLB when the complexity increases from agar plate assays to plant microcosm experiments. This suggests the occurrence of low levels of antibiotic production and/or that the two bacterial genera occupy different niches in the rhizosphere.

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There is very limited data on isolated systemic relapses of primary central nervous system lymphomas (PCNSL). We retrospectively reviewed the clinical characteristics and outcome of 10 patients with isolated systemic disease among 209 patients with PCNSL mainly treated with methotrexate-based chemotherapy (CT) with or without radiation therapy (RT). Isolated systemic relapse remained rare (4.8%, 10/209 patients). Median time from initial diagnosis to relapse was 33 months (range, 3-94). Sites of relapse were mostly extranodal. Three patients presented with early extra-cerebral (EC) relapse 3, 5 and 8 months from the beginning of initial treatment, respectively, and 7 patients had later relapses (range, 17-94 months). Treatment at relapse included surgery alone, RT alone, CT with or without radiotherapy, or CT with autologous stem cell transplantation (ASCT). Median overall survival (OS) after relapse was 15.5 months (range, 5.8-24.5) compared to 4.6 months (range, 3.6-6.5) for patients with central nervous system (CNS) relapse (p = 0.35). In conclusion, isolated systemic relapses exist but are infrequent. Early EC relapse suggests the presence of systemic disease undetectable by conventional evaluation at initial diagnosis. Patient follow-up must be prolonged because systemic relapse can occur as late as 10 years after initial diagnosis. Whether EC relapses of PCNSL have a better prognosis than CNS relapses needs to be assessed in a larger cohort. Copyright © 2010 John Wiley & Sons, Ltd.