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91.
A 67-year-old man under hemodialysis treatment developed neck stiffness, fever and conscious disturbances. The patient was infected with Methicilin-resistant Staphylococcus aureus (MRSA) sepsis caused by an infection on a dialysis shunt. On admission, he was diagnosed with bacterial meningoencephalitis and underwent a series of antibiotic chemotherapies. The treatment brought cell count in the cerebrospinal fluid to a subnormal level but his clinical status did not improve. The patient continued to have high level of cerebrospinal fluid protein (898 mg/dl). Cervical MRI demonstrated two abscesses deep in the neck as well as in the epidural region of the cervical spinal cord, from C2 to C5 vertebral levels. Based on these findings, spinal epidural abscess (SEA) was diagnosed. Intensive antibiotic chemotherapy especially targeted for MRSA could eradicate abscesses and improve clinical status. However, persistent high protein level in the cerebrospinal fluid could suggest SEA.  相似文献   
92.
Background: The mechanism of epidural infection associated with epidural block is not clearly understood. Resident organisms in skin specimens were studied after skin was prepared with disinfectants.

Methods: Sixty-nine paired skin specimens were excised at incisional sites after skin disinfection with 10% povidone-iodine (10% PVP-I) or 0.5% chlorhexidine in 80% ethanol (0.5% CHE) from 60 patients having back surgery. One of the specimen pairs was placed in 10 ml brain-heart infusion broth and incubated in air at 37 degrees Celsius for 96 h. The other specimen was sectioned at 3 micro meter and prepared with Gram's stain for examination with the microscope.

Results: Thirteen gram-positive staphylococcal species (Staphylococcus epidermidis, 69.2%; S. hyicus, 15.4%; and S. capitis, 15.4%) were isolated from cultures. The isolates were found in a significantly greater proportion of the skin specimens disinfected with 10% PVP-I than in those disinfected with 0.5% CHE (11 of 34 cultures [32.4%] vs. 2 of 35 cultures [5.7%]; P < 0.01). Many gram-positive cocci were observed with the microscope in 4 (11.8%) and 5 (14.3%) of 34 and 35 skin specimens disinfected with 10% PVP-I and 0.5% CHE, respectively. The cocci formed a dense colony in each follicle and in the stratum corneum. No organism was present in any of 17,584 sweat glands examined.  相似文献   

93.
Differences in susceptibility to N-butyl-N-(4-hydroxybutyl)nitrosamine (BBN)-induced urinary bladder carcinogenesis between two substrains of male Sprague-Dawley rats were examined. One substrain was SD/gShi, which has spontaneous hypospermatogenesis, and the other was SD/cShi, which is a sister strain of SD/gShi, and has normal testis but spontaneous hydronephrosis. SD/gShi rats had a lower incidence of urinary bladder tumors and had lower 5-bromo-2'-deoxyuridine labeling indices in the urinary bladder epithelium than SD/cShi rats when BBN was given. SD/gShi rats had significantly lower urinary concentrations of N-butyl-N-(3-carboxypropyl)nitrosamine (BCPN), which is a metabolite and proximate carcinogen of BBN. In vitro analysis also showed significantly less BCPN formation, using an S9 mix derived from the liver and kidney, in SD/gShi rats than in SD/cShi rats. BCPN formation in vitro was markedly inhibited by non-selective cytochrome P450 (CYP) inhibitors, but not alcohol dehydrogenase inhibitor. However, analysis of CYP proteins including hepatic CYP1A1/2, 2B1/2, 2E1, and 3A2 and renal CYP2E1 and 3A2 revealed no significant variation in levels in either tissue in the groups. There were also no significant intergroup differences in the mutagenicity of carcinogens, including heterocyclic amines and N-nitrosamines, activated by CYP1A1/2 and CYP2E1 and/or CYP2B1/2, respectively. These results suggest that SD/gShi rats are less susceptible to BBN, possibly because less BCPN is produced by CYP isoforms other than those investigated. A contribution of CYP4B1 to the strain difference is also possible.  相似文献   
94.
The ethanolic extracts from the roots, the underground trunk and the leaves of Aiouea trinervis were active in the brine shrimp (Artemia salina) lethality assay (LD (50): 1.93, 0.92 and 262.1 microg/mL, respectively). Fractionation of the extracts led to the isolation of four butanolides, namely (-)-epilitsenolides C (2) and C (1) ( 1 and 2), isoobtusilactone A ( 3) and obtusilactone A ( 4), two of which ( 1 and 2) are reported for the first time as genuine natural products. The lignans (+)-sesamin ( 5) and (+)-methylpiperitol ( 6) and polyprenol-12 ( 7) were isolated as well. Their structures were determined with spectral methods (1D-, 2D-NMR and MS). Compounds 1, 2, 3, 5 and 6 were tested for their cytotoxic activities in Hep (2) human cancer cells. The butanolides 2 and 3 were the most active (IC (50): 5.96 microg/mL and 4.95 microg/mL, respectively) whereas the other compounds showed moderate IC (50) values ranging from 12.20 microg/mL to 25.64 microg/mL. The genotoxic properties of the crude ethanolic extracts and of compounds 3 and 5 were also evaluated in this study on CHO K1 and HTC mammalian cells with single-cell gel electrophoresis (comet assay). The crude extracts as well as the compounds tested induced DNA migration in this assay, which was indicative of DNA damage (genotoxic effect).  相似文献   
95.
Background Messenger RNA of liver fatty acid-binding protein (L-FABP) is expressed in proximal tubules of the kidney, and a certain amount is excreted into urine. We analyzed factors relating to the urinary L-FABP excretion in health-check participants.Methods We measured L-FABP in the first morning urine by ELISA in 715 men and 193 women 30–79 years of age who entered a 2-day hospitalized health checkup program. In addition to the routine physical examination and laboratory tests, plasma high-sensitivity C-reactive protein (HSCRP) was assayed.Results In 150 healthy subjects, urinary L-FABP averaged 3.6 ± 0.2µg/g creatinine, whereas the values were significantly increased in patients with hypertension (5.2 ± 0.4, P = 0.010), diabetes mellitus (5.5 ± 0.5, P < 0.001), and chronic hepatitis (5.8 ± 1.0, P = 0.022). Urinary L-FABP excretion was significantly greater in women than in men when the value was related to creatinine. In regression analysis in men, urinary L-FABP was positively correlated with fasting plasma glucose (r = 0.103, P = 0.033) and plasma HSCRP (r = 0.135, P = 0.006).Conclusions It is suggested that renal production and urinary excretion of L-FABP are increased in situations in which arteriosclerosis is promoted, such as hypertension, diabetes mellitus, and cardiovascular inflammation.  相似文献   
96.
Background Reactive oxygen species are as being related to the pathophysiology of endstage renal disease (ESRD). We measured the plasma hydroxyl radical (·OH)-producing ability and ·OH-scavenging activity in patients with ESRD to clarify the pathophysiological states involved. Methods We used electron spin resonance to measure plasma N-t-butyl-α-phenylnitron radical spin adduct (pPBN rsa) as ·OH-producing ability and plasma 3,3,5,5-tetramethyl-1-pyrroline-N-oxide radical spin adduct (pM4PO rsa) as ·OH-scavenging activity. Oxidative injuries were evaluated by determining oxidised low-density lipoprotein (Ox-LDL). Results The pPBN rsa of the ESRD patients was lower than that of the controls (1.83 vs 2.94 μmol/g protein). The pM4PO rsa of the ESRD patients was higher than that of the controls (3.85 vs 3.15 mmol l-ascorbic acid 2-[3,4-dihydro-2,5,7,8-tetramethyl-2-(4,8,12-trimethyltridecyl)-2H-1-benzopyran-6-yl hydrogen phosphate] potassium salt (EPC-K1)/g protein). The pPBN rsa and pM4PO rsa were correlated, both in the ESRD patients and in the controls (r = 0.47 and r = 0.53). Ox-LDL was correlated with hemodialysis (HD) duration (r = 0.49) and was negatively correlated with pPBN rsa (r = −0.54), which indicates that oxidative stress was increased as HD therapy was prolonged and suppressed pPBN rsa. Conclusions There was an imbalance between ·OH-producing ability and ·OH-scavenging activity, in the ESRD patients, and this may be responsible for compromising the health of ESRD patients.  相似文献   
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DHPLC in clinical molecular diagnostic services   总被引:6,自引:0,他引:6  
A high-capacity low-cost mutation scanning method based on denaturing high-performance liquid chromatography (DHPLC) has been recently introduced. We have implemented an automated and cost-effective strategy using DHPLC. To facilitate the semi-automated analysis of multiple exons, two steps were taken. The first step was the development of a PCR protocol for the amplification of multiple exons under the same conditions. Primer sets, which amplify each exon in the entire gene, were aliquoted to and air-dried on a 96-well format PCR plate. In this way, all the exons in a gene can be simultaneously amplified on a single PCR machine. The second step was the serial DHPLC analysis of multiple amplicons under conditions optimal for each amplicon. We named the 96-well plate containing the primer pairs and the corresponding computer file used to analyze each amplicon under the pre-determined optimal conditions as the "Condition-Oriented-PCR primer-Embedded-Reactor plate," or the COPPER plate. We have developed COPPER plate systems for more than 20 congenital disorders including classic congenital syndromes like Marfan syndrome (FBN1: 65 amplicons), CHARGE syndrome (CHD7: 39 amplicons), de Lange syndrome (NIPBL: 46 amplicons), Sotos syndrome (NSD1: 30 amplicons), and Rubinstein-Taybi syndrome (CREBBP: 41 amplicons). Using the COPPER plate system, we are functioning as a reference laboratory for the clinical molecular diagnosis of congenital malformation syndromes and are presently analyzing more than 200 samples annually from all over Japan.  相似文献   
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