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41.
Genome modifications that occur at the initial interspecific hybridization event are dynamic and can be consolidated during the process of stabilization in successive generations of allopolyploids. This study identifies the number and chromosomal location of ribosomal DNA (rDNA) sites between Secale cereale, Dasypyrum villosum, and their allotetraploid S. cereale × D. villosum hybrids. For the first time, we show the advantages of FISH to reveal chromosome rearrangements in the tetraploid Secale × Dasypyrum hybrids. Based on the specific hybridization patterns of ribosomal 5S, 35S DNA and rye species-specific pSc200 DNA probes, a set of genotypes with numerous Secale/Dasypyrum translocations of 1R/1V chromosomes were identified in successive generations of allotetraploid S. cereale × D. villosum hybrids. In addition we analyse rye chromosome pairs using FISH with chromosome-specific DNA sequences on S. cereale × D. villosum hybrids.  相似文献   
42.
Mutations in the myelin protein zero (MPZ) gene are the third most frequent cause of hereditary motor and sensory neuropathies (HMSN), also called Charcot–Marie–Tooth disorders (CMT). Only in case of recurrent mutations occurring in the MPZ gene is it possible to draw phenotype–genotype correlations essential for establishing the prognosis and outcomes of CMT1. We have surveyed a cohort of 67 Polish patients from CMT families with demyelinating neuropathy for mutations in the MPZ gene. In this study, we report two CMT families in which the Ile135Thr and Pro132Leu mutations have been identified for the MPZ gene. These MPZ gene mutations had not been identified hitherto in the Polish population. The Pro132Leu mutation segregates with a severe early-onset dysmyelinating–hypomyelinating neuropathy, whereas the Ile135Thr substitution is associated with the classical phenotype of CMT1. To the best of our knowledge, we present here, for the first time, morphological data obtained in two sural nerve biopsies pointing to a hypomyelination–dysmyelination process in a family harboring the Pro132Leu mutation in the MPZ gene.  相似文献   
43.

Background

We evaluated the Ziehl-Neelsen staining (ZNS) technique for the diagnosis of paragonimiasis in Laos and compared different modifications of the ZNS techniques.

Methodology

We applied the following approach: We (1) examined a paragonimiasis index case''s sputum with wet film direct examination (WF) and ZNS; (2) re-examined stored ZNS slides from two provinces; (3) compared prospectively WF, ZNS, and formalin-ether concentration technique (FECT) for sputum examination of patients with chronic cough; and (4) compared different ZNS procedures. Finally, we assessed excess direct costs associated with the use of different diagnostic techniques.

Principal Findings

Paragonimus eggs were clearly visible in WF and ZNS sputum samples of the index case. They appeared brownish-reddish in ZNS and were detected in 6 of 263 archived ZNS slides corresponding to 5 patients. One hundred sputum samples from 43 patients were examined with three techniques, which revealed that 6 patients had paragonimiasis (13 positive samples). Sensitivity per slide of the FECT, ZNS and the WF technique was 84.6 (p = 0.48), 76.9 (p = 0.25) and 61.5% (p = 0.07), respectively. Percentage of fragmented eggs was below 19% and did not differ between techniques (p = 0.13). Additional operational costs per slide were 0 (ZNS), 0.10 US$ (WF), and 0.79 US$ (FECT). ZNS heated for five minutes contained less eggs than briefly heated slides (29 eggs per slide [eps] vs. 42 eps, p = 0.01). Bloodstained sputum portions contained more eggs than unstained parts (3.3 eps vs. 0.7 eps, p = 0.016).

Conclusions/Significance

Paragonimus eggs can easily be detected in today''s widely used ZNS of sputum slides. The ZNS technique appears superior to the standard WF sputum examination for paragonimiasis and eliminates the risk of tuberculosis transmission. Our findings suggest that ZNS sputum slides should also be examined routinely for Paragonimus eggs. ZNS technique has potential in epidemiological research on paragonimiasis.  相似文献   
44.
Giardia intestinalis is a complex species divided into 7 assemblages (A - G). Two of them (A and B) are infective for both humans and animals. In cats four assemblages can occur: A, B, D, and F Assemblages A and B infect either cats, dogs and humans, assemblage D infects cats and dogs and assemblage F only cats. The purpose of this study was to determine the prevalence and genotypes of G. intestinalis in cats from Warsaw. From November 2006 to March 2007 a hundred sixty samples of stool were collected and examined by light microscopy. G. intestinalis cysts were detected in 3.75% of samples. DNA extracted from positive samples was used as template for PCR-RFLP using Giardia specific primers and the amplicons were sequenced. A comparison of the obtained DNA sequences with the Giardia sequences in the GeneBank database revealed assemblage A in 1.25% of the investigated cats, assemblage B in 1.25% and D in 1.25%.  相似文献   
45.
IV characteristics for synthetic melanin were investigated at – 10 and 25°C. It was found that the Ohm law is valid for low voltages whereas the Child law holds for higher ones. Furthermore, the steady state electrical conductivity was estimated. The change of activation energy from 0.76 eV for low temperatures to 1.58 eV was noticeable near 0°C.  相似文献   
46.
Light microscopic observations were made on 22 ovules from fertile plants and 108 ovules from sterile plants of the cv. KS synaptic mutant, a highly male-sterile, female-sterile line of soybean [Glycine max (L.) Merr.] (2n = 2x = 40). Ovules of fertile siblings contained normal embryo sacs and embryos. Ovules from sterile plants contained various irregularities. The most consistent abnormality was the failure of the embryo sac to attain normal size. Small megasporocytes of irregular shape were seen; only one megasporocyte of normal shape and size was noted. No linear tetrads were found. However, two ovules contained nonlinear triads. A range from zero to 28 cells and nuclei, of various sizes, were identifiable in small megagametophytes and embryo sacs. Degeneration of these nuclei and cells was noted as early as the four-nucleate gametophyte stage. Other ovules contained degenerated nucellar centers without embryo sacs. Two ovules appeared to be normal. Late postpollination stages were marked by shrunken nucellus and integuments. The presence of pollen tube traces, endosperm, and aborting embryos in ovules of hand-pollinated flowers from sterile plants suggested that no incompatibility was involved. Degeneration of the gametophyte and embryo sac contents at many developmental stages indicated a wide array of effects, possibly resulting from meiotic irregularities similar to those seen in microsporogenesis of this mutant.  相似文献   
47.
48.
Shoots of Centaurium erythraea Rafn were cultivated in 5 l mist trickling bioreactor for 21 and 28 days increasing their dry weight from 0.54 g to 13.7 g and 18.3 g, respectively. About 6880 shoots from 223 initial shoot-tips in 21-day bioreactor producing cycle were produced. The shoots could be successfully rooted and transferred to soil. Secoiridoid accumulation (expressed as a sum of gentiopicroside, sweroside and swertiamarin) in shoots after 21 days of culture reached about 303 mg l−1.  相似文献   
49.
IgA, IgG and IgM antibodies against Yersinia Yop proteins, Yersinia LPS and Salmonella LPS from different serogroups were determined by enzyme-linked immunosorbent assay (ELISA) in a 885 serum samples and 92 synovial fluids. The control group consisted of 200 healthy blood donors. Compared with control subjects, patients with arthritis showed significantly increased titres of antibodies against Yersinia Yop, Yersinia LPS and Salmonella LPS appropriately in 21.7%, 44.0% and 56.0% serum samples. The prevalence of positive antibody levels was highest in Yersinia serogroup O3 and Salmonella serogroup B and D antibodies. The IgA titres were found to be much higher in adults than in children and youngsters but IgM titres consequently decreased with age. Investigation of synovial fluids obtained from patients with arthritis showed that Yersinia and Salmonella antibodies in synovial fluid mirror those in serum by concentration, by specificity and by distribution in classes.  相似文献   
50.
The aim of the study was to assess frequency and susceptibility to antimicrobial agents of non-fermenting gram-negative rods isolated from clinical specimens obtained from patients requiring intensive care, with emphasis on profile of the unit. Identification of cultured isolates was done using automated VITEK and API systems (bioMerieux, France). Susceptibility to antimicrobial agents was tested by a disk-diffusion method according to the NCCLS recommendations. In total the analysis comprised 425 strains of non-fermenting gram-negative rods, constituting 58.9% of all isolates of gram-negative bacteria. In blood cultures predominated strains of A. baumannii (46.8%) and P. aeruginosa (40.4%), while in cultures of other clinical specimens these bacteria comprised 42.9% and 43.9% of isolates. Major differences were observed in frequency of these species on both ICU units. Strains of non-fermenting rods isolated from blood cultures comprised a lower percentage of strains susceptible to antimicrobials (particularly cefepime and carbapenems) than isolates cultured from other specimens. Strains of A. baumannii resistant to imipenem and meropenem were detected with a frequency of 12.5% and 26.7%, respectively. Resistance of P. aeruginosa strains to carbapenems was 62.2% and 44.3%, respectively. There was a relatively high percentage of strains susceptible to cefepime (82.0%), ceftazidime (78.9%), amikacin (77.8%) and piperacillin/tazobactam (69.7%). Conclusions: 1. There was a predominance (58.9%) of strains of gram-negative non-fermenting rods. 2. Isolates from blood cultures were characterised by a much higher percentage of resistant strains in comparison to other specimens. 3. Strains of A. baumannii resistant to carbapenems were recorded. 4. There were differences in frequency and antimicrobial susceptibility among the strains of P. aeruginosa and A. baumannii depending on the type of clinical specimen and ICU profile.  相似文献   
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