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141.
Vincent C. C. Cheng Jasper F. W. Chan Antonio H. Y. Ngan Kelvin K. W. To S. Y. Leung H. W. Tsoi W. C. Yam Josepha W. M. Tai Samson S. Y. Wong Herman Tse Iris W. S. Li Susanna K. P. Lau Patrick C. Y. Woo Anskar Y. H. Leung Albert K. W. Lie Raymond H. S. Liang T. L. Que P. L. Ho K. Y. Yuen 《Journal of clinical microbiology》2009,47(9):2834-2843
Sinopulmonary and rhinocerebral zygomycosis has been increasingly found in patients with hematological malignancies and bone marrow transplantation, but intestinal zygomycosis remains very rare in the literature. We investigated an outbreak of intestinal infection due to Rhizopus microsporus in 12 patients on treatment for hematological malignancies over a period of 6 months in a teaching hospital. The intake of allopurinol during hospitalization (P < 0.001) and that of commercially packaged ready-to-eat food items in the preceding 2 weeks (P < 0.001) were found to be independently significant risk factors for the development of intestinal zygomycosis. A total of 709 specimens, including 378 environmental and air samples, 181 food samples, and 150 drug samples, were taken for fungal culture. Among them, 16 samples of allopurinol tablets, 3 prepackaged ready-to-eat food items, and 1 pair of wooden chopsticks were positive for Rhizopus microsporus, which was confirmed by ITS1-5.8S-ITS2 rRNA gene cluster (internal transcribed spacer [ITS]) sequencing. The mean viable fungal counts of allopurinol obtained from wards and pharmacy were 4.22 × 103 CFU/g of tablet (range, 3.07 × 103 to 5.48 × 103) and 3.24 × 103 CFU/g of tablet (range, 2.68 × 103 to 3.72 × 103), respectively, which were much higher than the mean count of 2 × 102 CFU/g of food. Phylogenetic analysis by ITS sequencing showed multiple clones from isolates of contaminated allopurinol tablets and ready-to-eat food, of which some were identical to patients'' isolates, and with one isolate in the cornstarch used as an excipient for manufacture of this drug. We attempted to type the isolates by random amplification of polymorphic DNA analysis, with limited evidence of clonal distribution. The primary source of the contaminating fungus was likely to be the cornstarch used in the manufacturing of allopurinol tablets or ready-to-eat food. Rhizopus microsporus is thermotolerant and can multiply even at 50°C. The long holding time of the intermediates during the manufacturing process of allopurinol amplified the fungal load. Microbiological monitoring of drugs manufactured for highly immunosuppressed patients should be considered.Zygomycosis has become an important emerging infection in patients with hematological malignancy undergoing chemotherapy or bone marrow transplantation (24), especially with the availability of voriconazole as antifungal prophylaxis (25, 28, 44). Breakthrough zygomycosis in patients on voriconazole prophylactic treatment is usually manifested as sinopulmonary or rhinocerebral disease, since the fungal spores are ubiquitously found in the environment and could therefore be acquired through inhalation or traumatic inoculation through the skin or mucosa. Gastrointestinal zygomycosis has been a rare clinical entity (50, 54), but cases or outbreaks of tongue, gastric, or cutaneous zygomycosis due to Rhizopus microsporus after exposure to contaminated wooden tongue depressors have been reported (23, 26, 33).The Rhizopus microsporus species group, which belongs to the class Zygomycetes and the order Mucorales, can cause life-threatening infections in immunocompromised patients (9, 39, 46). The laboratory diagnosis of R. microsporus relies mainly on the characteristic microscopic and phenotypic features of the fungal mycelium culture on agar medium. A molecular diagnostic test for this fungus is not widely available. PCR amplification and sequencing of the 18S and 28S rRNA genes (58, 64), internal transcribed spacer (ITS) region of rRNA (27), and recently PCR restriction fragment length polymorphism (22) and high-affinity iron permease gene sequence have been used to identify members of the clinically important Zygomycetes (30).Here we report an unprecedented outbreak of intestinal zygomycosis due to R. microsporus as a result of the oral intake of contaminated allopurinol tablets and ready-to-eat food items in patients with hematological malignancies undergoing chemotherapy and bone marrow transplantation. The clinical spectrum of this outbreak of intestinal infection by R. microsporus ranges from asymptomatic colonization to mucosal involvement to invasive disease. 相似文献
142.
143.
Jianyong Tang Jasper Akerboom Alipasha Vaziri Loren L. Looger Charles V. Shank 《Proceedings of the National Academy of Sciences of the United States of America》2010,107(22):10068-10073
Imaging approaches based on single molecule localization break the diffraction barrier of conventional fluorescence microscopy, allowing for bioimaging with nanometer resolution. It remains a challenge, however, to precisely localize photon-limited single molecules in 3D. We have developed a new localization-based imaging technique achieving almost isotropic subdiffraction resolution in 3D. A tilted mirror is used to generate a side view in addition to the front view of activated single emitters, allowing their 3D localization to be precisely determined for superresolution imaging. Because both front and side views are in focus, this method is able to efficiently collect emitted photons. The technique is simple to implement on a commercial fluorescence microscope, and especially suitable for biological samples with photon-limited chromophores such as endogenously expressed photoactivatable fluorescent proteins. Moreover, this method is relatively resistant to optical aberration, as it requires only centroid determination for localization analysis. Here we demonstrate the application of this method to 3D imaging of bacterial protein distribution and neuron dendritic morphology with subdiffraction resolution. 相似文献
144.
Jasper Stevens Ernst Suidgeest Piet Hein van der Graaf Meindert Danhof Elizabeth C. M. de Lange 《Pharmaceutical research》2009,26(8):1911-1917
Purpose To develop a new minimal-stress model for intranasal administration in freely moving rats and to evaluate in this model the
brain distribution of acetaminophen following intranasal versus intravenous administration.
Methods Male Wistar rats received one intranasal cannula, an intra-cerebral microdialysis probe, and two blood cannulas for drug administration
and serial blood sampling respectively. To evaluate this novel model, the following experiments were conducted. 1) Evans Blue
was administered to verify the selectivity of intranasal exposure. 2) During a 1 min infusion 10, 20, or 40 μl saline was
administered intranasally or 250 μl intravenously. Corticosterone plasma concentrations over time were compared as biomarkers
for stress. 3) 200 μg of the model drug acetaminophen was given in identical setup and plasma, and brain pharmacokinetics
were determined.
Results In 96% of the rats, only the targeted nasal cavity was deeply colored. Corticosterone plasma concentrations were not influenced,
neither by route nor volume of administration. Pharmacokinetics of acetaminophen were identical after intravenous and intranasal
administration, although the Cmax in microdialysates was reached a little earlier following intravenous administration.
Conclusion A new minimal-stress model for intranasal administration in freely moving rats has been successfully developed and allows
direct comparison with intravenous administration. 相似文献
145.
Rijkers K van Aalst J Kurt E Daemen MA Beuls EA Spincemaille GH 《Journal of neurosurgery》2009,110(2):274-278
The authors present the case of a 49-year-old female patient with complex regional pain syndrome-Type I (CRPSI) who was suffering from nonhealing wounds and giant bullae, which dramatically improved after spinal cord stimulation (SCS). The scientific literature concerning severe cutaneous manifestations of CRPS-I and their treatment is reviewed. Nonhealing wounds and bullae are rare manifestations of CRPS-I that are extremely difficult to treat. Immediate improvement of both wounds and bullae after SCS, such as in this case, has not been reported previously in literature. Considering the rapidly progressive nature of these severe skin manifestations, immediate treatment, possibly with SCS, is mandatory. 相似文献
146.
Olatunji BO Feldman G Smits JA Christian KM Zalta AK Pollack MH Simon NM 《Depression and anxiety》2008,25(2):167-171
Pharmacotherapy is an effective treatment for generalized anxiety disorder (GAD), but few studies have examined the nature of decline of anxiety and depression during pharmacotherapy for GAD and even fewer studies have examined predictors of symptom decline. This study examined the decline in symptoms of anxiety and depression in patients with GAD during a 6-week open trial of fluoxetine. Growth curve analyses indicated that pharmacotherapy with fluoxetine led to significant declines in symptoms of anxiety and depression over the 6 weeks of treatment. However, the decay slope observed for anxiety symptoms was significantly greater than that for depressive symptoms. Further analyses revealed that the decline in anxiety remained significant after accounting for the changes in symptoms of depression. However, the effect of treatment on depression was no longer significant after controlling for the reduction in anxiety symptoms. Overall anxiety sensitivity (AS) did not moderate the level of reduction in symptoms of anxiety or depression during pharmacotherapy. However, AS specific to physical concerns demonstated a marginal negative association with decline in anxiety and depression. AS specific to social concerns also demonstrated a marginal negative association with decline in anxiety symptoms. These findings suggest that the decline in anxiety symptoms is independent of the decline in symptoms of depression during pharmacotherapy for GAD and specific AS dimensions may predict symptom change in GAD. 相似文献
147.
Salvi J Jasper A Ricardi-Branco F Bernardes-de-Oliveira ME Guerra-Sommer M 《Anais da Academia Brasileira de Ciências》2008,80(3):553-563
The genus Lycopodites, which encompasses the herbaceous forms of the lycopsids, presents broad time and spacial distribution during the Paleozoic in the Northern Hemisphere, with its initial records dating from the European Devonian. As to Gondwanan Paleozoic, to this moment, only Lycopodites amazonica Dolianiti had been reported for the Amazonian Middle Devonian (Curuá Group). Thus, the specimens reported in this study such as Lycopodites sp., coming from sedimentary rocks of the Itararé Subgroup, S?o Paulo State, and Lycopodites riograndensis sp. nov., collected in Rio Bonito Formation, Rio Grande do Sul, represent the oldest fertile forms recorded for Gondwana and the first ones to be described for the Paraná Basin. Its presence in layers, deposited after the end of the Neopaleozoic Glaciation, shows the appearance of new taxa in high latitudes, as well as the diversity of the lycopsids present in the Basin, previously indicated through the abundance of spores associated to the Class Lycopsida present in the palinomorphous assemblages. 相似文献
148.
Seena Grewal Karin Jasper Cathleen Steinegger Evelyn Yu Ahmed Boachie 《Eating disorders》2013,21(2):152-162
The purpose of this study was to examine factors associated with completion of an adolescent-only eating disorder day hospital program. A total of 65 adolescents were included. Completers were compared to non-completers on multiple variables including diagnosis, weight, and medication use. Adolescents who completed the program were more likely to have been prescribed antidepressants and less likely to purge. The two groups did not differ significantly on other variables. Few factors differentiated completers from non-completers of the eating disorder day hospital program. Further research is needed to determine the role medications or purging may play in completing treatment. 相似文献
149.
Ido G Bikker Jasper van Bommel Dinis Reis Miranda Jan Bakker Diederik Gommers 《Critical care (London, England)》2008,12(6):R145-6
Introduction
Functional residual capacity (FRC) reference values are obtained from spontaneous breathing patients, and are measured in the sitting or standing position. During mechanical ventilation FRC is determined by the level of positive end-expiratory pressure (PEEP), and it is therefore better to speak of end-expiratory lung volume. Application of higher levels of PEEP leads to increased end-expiratory lung volume as a result of recruitment or further distention of already ventilated alveoli. The aim of this study was to measure end-expiratory lung volume in mechanically ventilated intensive care unit (ICU) patients with different types of lung pathology at different PEEP levels, and to compare them with predicted sitting FRC values, arterial oxygenation, and compliance values.Methods
End-expiratory lung volume measurements were performed at PEEP levels reduced sequentially (15, 10 and then 5 cmH2O) in 45 mechanically ventilated patients divided into three groups according to pulmonary condition: normal lungs (group N), primary lung disorder (group P), and secondary lung disorder (group S).Results
In all three groups, end-expiratory lung volume decreased significantly (P < 0.001) while PEEP decreased from 15 to 5 cmH2O, whereas the ratio of arterial oxygen tension to inspired oxygen fraction did not change. At 5 cmH2O PEEP, end-expiratory lung volume was 31, 20, and 17 ml/kg predicted body weight in groups N, P, and S, respectively. These measured values were only 66%, 42%, and 34% of the predicted sitting FRC. A correlation between change in end-expiratory lung volume and change in dynamic compliance was found in group S (P < 0.001; R 2 = 0.52), but not in the other groups.Conclusions
End-expiratory lung volume measured at 5 cmH2O PEEP was markedly lower than predicted sitting FRC values in all groups. Only in patients with secondary lung disorders were PEEP-induced changes in end-expiratory lung volume the result of derecruitment. In combination with compliance, end-expiratory lung volume can provide additional information to optimize the ventilator settings. 相似文献150.
Vleggeert-Lankamp CL Wolfs J Pêgo AP van den Berg R Feirabend H Lakke E 《Journal of neurosurgery》2008,109(2):294-305
OBJECT: In the present study the authors consider the influence of the porosity of synthetic nerve grafts on peripheral nerve regeneration. METHODS: Microporous (1-13 microm) and nonporous nerve grafts made of a copolymer of trimethylene carbonate and epsilon-caprolactone were tested in an animal model. Twelve weeks after surgery, nerve and muscle morphological and electrophysiological results of regenerated nerves that had grown through the synthetic nerve grafts were compared with autografted and untreated (control) sciatic nerves. Based on the observed changes in the number and diameter of the nerve fibers, the predicted values of the electrophysiological parameters were calculated. RESULTS: The values of the morphometric parameters of the peroneal nerves and the gastrocnemius and anterior tibial muscles were similar if not equal in the rats receiving synthetic nerve grafts. The refractory periods, however, were shorter in porous compared with nonporous grafted nerves, and thus were closer to control values. CONCLUSIONS: A shorter refractory period enables the axon to follow the firing frequency of the neuron more effectively and allows a more adequate target organ stimulation. Therefore, porous are preferred over nonporous nerve grafts. 相似文献