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71.
George Tzovaras Ioannis Baloyiannis Andreas Kapsoritakis Athanassios Psychos George Paroutoglou Spyros Potamianos 《Surgical endoscopy》2010,24(10):2603-2606
Background
Although the ideal management of cholelithiasis and concomitant choledocholithiasis is controversial, the two-stage approach [endoscopic retrograde cholangiopancreatography (ERCP), sphincterotomy, and common bile duct (CBD) clearance followed by laparoscopic cholecystectomy] is the most popular treatment regimen worldwide. However, sometimes ERCP fails to solve the problem of choledocholithiasis preoperatively. The aim of this study was to evaluate the use of intraoperative ERCP using the laparoendoscopic “rendezvous” technique in patients in whom preoperative ERCP has failed or was not possible to attempt. 相似文献72.
73.
Vassilis Fotopoulos Maria L. Stavrinou Athanassios N. Skodras 《Journal of digital imaging》2011,24(5):943-949
One of the new challenges of Information Technology in the medical world is the protection and authentication of a variety
of digital medical files, datasets, and images. In this work, the ability of magnetic resonance imaging (MRI) slice sequences
to hide digital data is investigated and more specifically the case that the hidden data are the regions of interest (ROI)
of the MRI slices. The regions of non-interest (RONI) are used as cover. The hiding capacity of the whole sequence is taken
into account. Any ROI-targeted tampering attempt can be detected, and the original image can be self-restored (under certain
conditions) by extracting the ROI from the RONI. 相似文献
74.
Pitarokili D Michaelakis A Koliopoulos G Giatropoulos A Tzakou O 《Parasitology research》2011,108(2):425-430
Entamoeba histolytica is the etiologic agent for amoebiasis. The excretory–secretory (ES) products of the trophozoites contain virulence factors
and antigens useful for diagnostic applications. Contaminants from serum supplements and dead trophozoites impede analysis
of ES. Therefore, a protein-free medium that can sustain maximum viability of E. histolytica trophozoites for the longest time duration will enable collection of contaminant-free and higher yield of ES products. In
the present study, we compared the efficacy of four types of media in maintaining ≥95% trophozoite viability namely Roswell
Memorial Park Institute (RPMI-1640), Dulbecco’s Modified Eagle Medium (DMEM), phosphate-buffered saline for amoeba (PBS-A),
and Hank’s balanced salt solution (HBSS). Concurrently, the effect of adding l-cysteine and ascorbic acid (C&A) to each medium on the parasite viability was also compared. DMEM and RPMI 1640 showed higher
viabilities as compared to PBS-A and HBSS. Only RPMI 1640 showed no statistical difference with the control medium for the
first 4 h, however the ≥95% viability was only maintained for the first 2 h. The other protein-free media showed differences
from the serum- and vitamin-free TYI-S-33 control media even after 1 h of incubation. When supplemented with C&A, all media
were found to sustain higher trophozoite viabilities than those without the supplements. HBSS-C&A, DMEM-C&A, and RPMI 1640-C&A
demonstrated no difference (P > 0.05) in parasite viabilities when compared with the control medium throughout the 8-h incubation period. DMEM-C&A showed
an eightfold increment in time duration of sustaining ≥95% parasite viability, i.e. 8 h, as compared to DMEM alone. Both RPMI
1640-C&A and HBSS-C&A revealed fourfold and threefold increments (i.e., 8 and 6 h, respectively), whereas PBS-A-C&A showed
only onefold improvement (i.e., 2 h) as compared to the respective media without C&A. Thus, C&A-supplemented DMEM or RPMI
are recommended for collection of ES products. 相似文献
75.
Siatelis A Houhoula DP Papaparaskevas J Delakas D Tsakris A 《Journal of clinical microbiology》2011,49(4):1206-1208
A real-time PCR targeting IS6110 was employed for the detection of Mycobacterium tuberculosis DNA in specimens collected from 10 patients treated with intravesical M. bovis bacillus Galmette-Guérin (BCG) immunotherapy for bladder malignancy. BCG DNA was detected in all urine specimens taken 24 h after the instillations, as well as in 24% of the specimens collected 7 days after the instillations; it was also detected in a single specimen taken 6 weeks after the last instillation. BCG DNA was detected in 8.3% of the blood specimens taken 1 day after instillation, and its amplification was associated with cases of self-limiting fever. These findings give indications that this real-time PCR is helpful to recognize BCG bacteremic cases, which may lead to mycobacterial infection. 相似文献
76.
Agodi A Voulgari E Barchitta M Politi L Koumaki V Spanakis N Giaquinta L Valenti G Romeo MA Tsakris A 《Journal of clinical microbiology》2011,49(11):3986-3989
From March 2009 to May 2009, 24 carbapenem-resistant Klebsiella pneumoniae isolates were recovered from 16 patients hospitalized in an Italian intensive care unit (ICU). All isolates contained KPC-3 carbapenemase and belonged to a single pulsed-field gel electrophoresis (PFGE) clone of multilocus sequence type 258 (designated as ST258). A multimodal infection control program was put into effect, and the spread of the KPC-3-producing K. pneumoniae clone was ultimately controlled without closing the ICU to new admissions. Reinforced infection control measures and strict monitoring of the staff adherence were necessary for the control of the outbreak. 相似文献
77.
78.
Athanassios Tsakris Aggeliki Poulou Katerina Themeli-Digalaki Evangelia Voulgari Theodore Pittaras Danai Sofianou Spyros Pournaras Dimitra Petropoulou 《Journal of clinical microbiology》2009,47(11):3420-3426
We evaluated boronic acid (BA)-based methods for their ability to detect extended-spectrum β-lactamases (ESBLs) among clinical isolates of KPC-producing members of the Enterobacteriaceae family. A total of 155 isolates of Klebsiella pneumoniae (n = 141), Escherichia coli (n = 6), Enterobacter aerogenes (n = 6), and Klebsiella oxytoca (n = 2) genotypically confirmed to be KPC producers were analyzed. As many as 118 isolates harbored ESBLs (103 harbored SHV-type ESBLs, 13 harbored CTX-M-type ESBLs, and 2 harbored both SHV- and CTX-M-type ESBLs); the remaining 37 isolates were genotypically negative for ESBL production. The CLSI ESBL confirmatory test was positive for 79 of the 118 ESBL producers (sensitivity, 66.9%), while all 37 non-ESBL producers were negative (specificity, 100%). When a ≥5-mm increase in the zone diameter of either the cefotaxime (CTX)-clavulanate (CA) or the ceftazidime (CAZ)-CA disks containing BA compared with the zone diameter of the CTX or CAZ disks containing BA was considered to be a positive result for ESBL production, the method detected all 118 ESBL producers (sensitivity, 100%) and showed no false-positive results for non-ESBL producers (specificity, 100%). Double-disk synergy tests, in which disks of CTX, CAZ, aztreonam, or cefepime in combination with BA were placed at distances of 20, 25, and 30 mm (center to center) from a disk containing amoxicillin (amoxicilline)-clavulanate-BA, were able to detect 116 (98.3%), 101 (85.6%), and 28 (23.7%) of the ESBL-positive isolates, respectively; no false-positive results for non-ESBL-producing isolates were detected. Our results demonstrate that the modified CLSI ESBL confirmatory test with antibiotic disks containing BA is the most accurate phenotypic method for the detection of ESBLs in Enterobacteriaceae producing KPC carbapenemases.During the last decade, carbapenem resistance has emerged among clinical isolates of the Enterobacteriaceae family, and this is increasingly attributed to the production of β-lactamases capable of hydrolyzing carbapenems (23). Among these enzymes, a new type of Ambler class A β-lactamase, the Klebsiella pneumoniae carbapenemase (KPC), has been rapidly spreading among K. pneumoniae isolates and other Enterobacteriaceae in the northeastern regions of the United States and has now spread to several regions of North and South America, as well as in Israel, China, and Greece (2, 13, 16, 21).The current spread of KPC enzymes makes them a potential threat to currently available antibiotic-based treatments. These enzymes confer various levels of resistance to all β-lactams, including carbapenems, even though cefamycins and ceftazidime are only weakly hydrolyzed (15, 18). KPC-possessing strains frequently carry extended-spectrum β-lactamase (ESBL) genes (1, 3, 8, 13, 24), which could possibly contribute to the expression and dissemination of the β-lactam resistance trait (8, 18, 21). It should be also noted that KPCs and ESBLs are mostly plasmid-encoded determinants that can easily disseminate to other enterobacterial strains (3, 7, 15, 18, 26). Therefore, the phenotypic detection of ESBLs in KPC-producing isolates of the Enterobacteriaceae is of potential interest for epidemiological purposes as well as for limiting the spread of the underlying resistance mechanisms.The CLSI recommends a phenotypic confirmatory test for ESBL production that consists of measuring the growth-inhibitory zones around both cefotaxime (CTX) and ceftazidime (CAZ) disks with or without clavulanate (CA) for K. pneumoniae, Klebsiella oxytoca, Escherichia coli, and Proteus mirabilis (4). Different double-disk synergy tests (DDSTs) based on the synergy of amoxicillin (amoxicilline)-clavulanate (AMC) with extended-spectrum cephalosporins and aztreonam have also been extensively used for the detection of ESBLs (7). However, strategies for the laboratory identification of ESBLs need to be reviewed and adjusted as additional mechanisms of resistance to β-lactams coexist in enterobacterial strains (7). KPCs hydrolyze several β-lactam antibiotics, and hence, the presence of an ESBL can be masked by the expression of a KPC. Moreover, the weak inhibition of KPCs by the β-lactam inhibitors (15, 18, 30) may interfere with the interpretation of ESBL detection methods and KPC enzymes may be mistaken for ESBLs. Thus, there is a need to accurately detect ESBLs in the presence of coexisting KPC expression.Boronic acid (BA) compounds were recently reported to be reversible inhibitors of KPCs (6, 16, 27). In particular, we have shown that BA disk assays are considered positive for the detection of the KPC enzyme when the growth-inhibitory zone diameter around a meropenem, imipenem, or cefepime disk with phenylboronic acid is 5 mm or greater of the growth-inhibitory zone diameter around the disk containing meropenem or cefepime alone (27). The results of this study also showed that BA affected the activity of CAZ in ESBL-negative KPC-producing isolates but not in SHV ESBL-positive KPC-producing isolates, most likely due to the presence of the SHV ESBL, which is not restrained by BA (27). BA-based tests with disks of CAZ and CTX have also been successfully employed for the identification of ESBLs in AmpC producers (11, 25). These observations led us to design a modified CLSI ESBL confirmatory test using antibiotic disks containing BA as well as different DDSTs employing BA for the accurate detection of ESBLs in KPC-producing enterobacterial isolates. 相似文献
79.
Konstantina Dipla Theano Tsirini Andreas Zafeiridis Vasiliki Manou Athanassios Dalamitros Eleftherios Kellis Spyros Kellis 《European journal of applied physiology》2009,106(5):645-653
This study examined the maturation pattern of fatigue resistance (FR) from childhood to adulthood in females and males during
high-intensity intermittent exercise and compared FR between females and males in childhood and adolescence. Thirty males
(boys 11.3 ± 0.5 years, teen-males 14.7 ± 0.3 years, men 24.0 ± 2.1 years) and 30 females (girls 10.9 ± 0.6 years, teen-females
14.4 ± 0.7 years, women 25.2 ± 1.4) participated in this study. They performed high-intensity intermittent exercise (4 × 18
maximal knee flexions and extensions with 1-min rest) on an isokinetic dynamometer at 120°s−1. Peak torque of flexors (PTFL) and extensors (PTEX), and total work (TW) were measured. FR was calculated as % of PTEX, PTFL,
and TW in 4th versus 1st set. FR was greater (P < 0.05) in boys versus teen-males and men, and in teen-males versus men. In females, FR was greater (P < 0.05) in girls versus teen-females and women, but not different between teen-females and women. FR was not different in
boys versus girls and in teen-males versus teen-females. FR for PTFL, PTEX, and TW correlated negatively (P < 0.001) with the respective peak values (r = −0.68 to −0.84), and FR for TW with peak lactate (r = −0.58 to −0.69). In addition, age correlated (P < 0.01) with FR for males (r = −0.75) and females (r = −0.55). In conclusion, FR during high-intensity intermittent exercise undergoes a gradual decline from childhood to adulthood
in males, while in females the adult profile establishes at mid-puberty (14–15 years). The maturation profile of FR in males
and females during development appears to reflect the maturation profiles of peak torque, short-term muscle power, and lactate
concentration after exercise.
T. Tsirini and A. Zafeiridis contributed equally to this work. 相似文献
80.
We describe a 24-year-old man with episodes of intense desire to sleep for periods ranging from 2min to 3h, episodes of generalized weakness and inability to speak without alteration of consciousness, frequent hypnagogic hallucinations during sleep and occasionally transient paralysis of limbs upon awakening. Brain MRI demonstrated elevation of the third ventricle, a characteristic lack of depiction of the corpus callosum and extension of the bihemispheric fissure to the third ventricle. We assume that structural changes of the base of frontal lobes, diencephalon and brainstem, can be accountable for symptomatic narcolepsy and cataplexy. 相似文献