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21.

Background and Objectives

In the last decade, autosomal recessive IL-12Rβ1 deficiency has been diagnosed in four children with severe tuberculosis from three unrelated families from Morocco, Spain, and Turkey, providing proof-of-principle that tuberculosis in otherwise healthy children may result from single-gene inborn errors of immunity. We aimed to estimate the fraction of children developing severe tuberculosis due to IL-12Rβ1 deficiency in areas endemic for tuberculosis and where parental consanguinity is common.

Methods and Principal Findings

We searched for IL12RB1 mutations in a series of 50 children from Iran, Morocco, and Turkey. All children had established severe pulmonary and/or disseminated tuberculosis requiring hospitalization and were otherwise normally resistant to weakly virulent BCG vaccines and environmental mycobacteria. In one child from Iran and another from Morocco, homozygosity for loss-of-function IL12RB1 alleles was documented, resulting in complete IL-12Rβ1 deficiency. Despite the small sample studied, our findings suggest that IL-12Rβ1 deficiency is not a very rare cause of pediatric tuberculosis in these countries, where it should be considered in selected children with severe disease.

Significance

This finding may have important medical implications, as recombinant IFN-γ is an effective treatment for mycobacterial infections in IL-12Rβ1-deficient patients. It also provides additional support for the view that severe tuberculosis in childhood may result from a collection of single-gene inborn errors of immunity.  相似文献   
22.
This work reports a novel computational method based on augmented cell-graphs (ACG), which are constructed from low-magnification tissue images for the mathematical diagnosis of brain cancer (malignant glioma). An ACG is a simple, undirected, weighted and complete graph in which a node represents a cell cluster and an edge between a pair of nodes defines a binary relationship between them. Both the nodes and the edges of an ACG are assigned weights to capture more information about the topology of the tissue. In this work, the experiments are conducted on a dataset that is comprised of 646 human brain biopsy samples from 60 different patients. It is shown that the ACG approach yields sensitivity of 97.53% and specificities of 93.33 and 98.15% (for the inflamed and healthy, respectively) at the tissue level in glioma diagnosis.  相似文献   
23.
3,5-Diaryl pyrazolines analogs were synthesized and evaluated for their monoamine oxidase (MAO) inhibitory activity. The compounds were found reversible and selective towards MAO-A with selectivity index in the magnitude of 103–105. The docking studies were carried out to gain further structural insights of the binding mode and possible interactions with the active site of MAO-A. Interestingly, the theoretical (Ki) values obtained by molecular docking studies were in congruence with their experimental (Ki) values.  相似文献   
24.
Amikacin (AK) has nephrotoxic side effects. AK-induced nephrotoxicity may be the consequence of oxidative stress and so anti-oxidant agents could be useful in reducing AK toxicity. Caffeic acid phenethyl ester (CAPE) was recently shown to have free radical scavenging ability and it reduces lipid peroxidation. For this purpose, the rats were distributed into three groups: (I) injected with vehicle (control); (II) injected (i.p.) with 1.2 g kg(-1) AK at a single dose; (III) injected (i.p.) with AK plus 10 micromol kg(-1) CAPE. Renal morphology was investigated by light microscopy. Tissue samples and trunk blood were also obtained to determine renal malondialdehyde (MDA), blood urea nitrogen (BUN) and creatinine (Cr) levels. MDA production was found to be higher in rats given AK than among control rats. CAPE administration before AK injection caused a significant decrease in MDA production. Morphological tubule damage in rats given AK was severe in the renal cortex, whereas in rats given AK plus CAPE, no histological changes occurred. It is concluded that CAPE could be useful for reducing the nephrotoxic effects of AK. Copyright (c) 2005 John Wiley & Sons, Ltd.  相似文献   
25.
There has been a new interest in using aldehyde dehydrogenase (ALDH) activity as one marker for stem cells since the Aldefluor flow cytometry-based assay has become available. Diethylaminobenzaldehyde (DEAB), used in the Aldeflour assay, has been considered a specific inhibitor for ALDH1A1 isoform. In this study, we explore the effects of human ALDH isoenzymes, ALDH1A2 and ALDH2, on drug resistance and proliferation, and the specificity of DEAB as an inhibitor. We also screened for the expression of 19 ALDH isoenzymes in K562 cells using TaqMan Low Density Array (TLDA). We used lentiviral vectors containing the full cDNA length of either ALDH2 or ALDH1A2 to over express the enzymes in K562 leukemia and H1299 lung cancer cell lines. Successful expression was measured by activity assay, Western blot, RT-PCR, and Aldefluor assay. Both cell lines, with either ALDH1A2 or ALDH2, exhibited higher cell proliferation rates, higher clonal efficiency, and increased drug resistance to 4-hydroperoxycyclophosphamide and doxorubicin. In order to study the specificity of known ALDH activity inhibitors, DEAB and disulfiram, we incubated each cell line with either inhibitor and measured the remaining ALDH enzymatic activity. Both inhibitors reduced ALDH activity of both isoenzymes by 65-90%. Furthermore, our TLDA results revealed that ALDH1, ALDH7, ALDH3 and ALDH8 are expressed in K562 cells. We conclude that DEAB is not a specific inhibitor for ALDH1A1 and that Aldefluor assay is not specific for ALDH1A1 activity. In addition, other ALDH isoenzymes seem to play a major role in the biology and drug resistance of various malignant cells.  相似文献   
26.
Saccharomyces cerevisiae strain W303 is a widely used model organism. However, little is known about its genetic origins, as it was created in the 1970s from crossing yeast strains of uncertain genealogy. To obtain insights into its ancestry and physiology, we sequenced the genome of its variant W303-K6001, a yeast model of ageing research. The combination of two next-generation sequencing (NGS) technologies (Illumina and Roche/454 sequencing) yielded an 11.8 Mb genome assembly at an N50 contig length of 262 kb. Although sequencing was substantially more precise and sensitive than whole-genome tiling arrays, both NGS platforms produced a number of false positives. At a 378× average coverage, only 74 per cent of called differences to the S288c reference genome were confirmed by both techniques. The consensus W303-K6001 genome differs in 8133 positions from S288c, predicting altered amino acid sequence in 799 proteins, including factors of ageing and stress resistance. The W303-K6001 (85.4%) genome is virtually identical (less than equal to 0.5 variations per kb) to S288c, and thus originates in the same ancestor. Non-S288c regions distribute unequally over the genome, with chromosome XVI the most (99.6%) and chromosome XI the least (54.5%) S288c-like. Several of these clusters are shared with Σ1278B, another widely used S288c-related model, indicating that these strains share a second ancestor. Thus, the W303-K6001 genome pictures details of complex genetic relationships between the model strains that date back to the early days of experimental yeast genetics. Moreover, this study underlines the necessity of combining multiple NGS and genome-assembling techniques for achieving accurate variant calling in genomic studies.  相似文献   
27.
Automated cell imaging systems facilitate fast and reliable analysis of biological events at the cellular level. In these systems, the first step is usually cell segmentation that greatly affects the success of the subsequent system steps. On the other hand, similar to other image segmentation problems, cell segmentation is an ill-posed problem that typically necessitates the use of domain-specific knowledge to obtain successful segmentations even by human subjects. The approaches that can incorporate this knowledge into their segmentation algorithms have potential to greatly improve segmentation results. In this work, we propose a new approach for the effective segmentation of live cells from phase contrast microscopy. This approach introduces a new set of “smart markers” for a marker-controlled watershed algorithm, for which the identification of its markers is critical. The proposed approach relies on using domain-specific knowledge, in the form of visual characteristics of the cells, to define the markers. We evaluate our approach on a total of 1,954 cells. The experimental results demonstrate that this approach, which uses the proposed definition of smart markers, is quite effective in identifying better markers compared to its counterparts. This will, in turn, be effective in improving the segmentation performance of a marker-controlled watershed algorithm.  相似文献   
28.
ABSTRACT: INTRODUCTION: The combination of polyethylene glycol (PEG)ylated interferon (pegylated interferon) and ribavirin has been shown to be an effective treatment for chronic hepatitis C virus. In general, common side effects related to this combination therapy are mild and are well tolerated. However, peripheral neuropathy including demyelinating polyneuropathy related to PEG-interferon alpha2a (pegylated interferon alfa-2a) is extremely rare. In the literature, only one case of acute inflammatory demyelinating polyneuropathy related to PEG-interferon alpha2a has been published previously. CASE PRESENTATION: To the best of our knowledge we present only the second case of acute inflammatory demyelinating polyneuropathy related to PEG-interferon alpha2a, occurring in a 63-year-old Caucasian man. He developed tingling, numbness, and weakness of his upper and lower extremities with acute neurological deficits after five weeks of a combination therapy with PEG-interferon alpha2a and ribavirin for chronic hepatitis C virus infection. His clinical course, neurological findings, and his electromyogram results were all consistent with acute inflammatory demyelinating polyneuropathy. Our patient recovered completely after interferon was stopped and symptomatic treatment and a further electromyogram showed a disappearance of neuropathy. Four weeks later, PEG-interferon alpha2a was reintroduced with a gradually increasing dose without any reappearance of neurological symptoms allowing hepatitis C seroconversion. CONCLUSIONS: Recognition of this rare yet possible presentation is important for early and accurate diagnosis and treatment. This case report also suggests that the reintroduction of PEGylated interferon in patients who had presented with acute inflammatory demyelinating polyneuropathy related to interferon alpha may be safe, but this must be confirmed by further studies.  相似文献   
29.
The aim of this study was to investigate the effects of topotecan, a topoisomerase I-inhibiting anticancer agent, on hematologic parameters and serum levels of trace elements. The study was conducted on three groups consisting of 16 and 18 rabbits in the study groups and 15 rabbits in the control group. Rabbits in group I (n = 16) received high-dose topotecan intravenously (i.v.; 0.5 mg/kg once daily), while rabbits in group II (n = 18) received low-dose topotecan i.v. (0.25 mg/kg once daily) for 3 days. The 15 rabbits comprising the control group did not receive topotecan. Serum samples were collected from each rabbit on the first day, before the treatment, and on the 15th day of treatment. Erithrocytes, hemoglobin, white blood cell count, thrombocyte count, and trace elements such as selenium, copper, lead, zinc, and cobalt were analyzed. Hemoglobin levels and erythrocyte counts were lower in both study groups than in the control group. However, thrombocyte and leukocyte counts were similar in all three groups (p > 0.005). Serum trace element levels (copper, lead, zinc, and cobalt) did not differ significantly between groups. However, serum selenium levels were significantly lower in both study groups than the control group (p < 0.001). The results revealed that topotecan treatment causes a decrease in erythrocyte counts and hemoglobin levels due to bone marrow suppression, and these effects must be taken into account during treatment. In addition, selenium supplementation might be helpful in cancer patients receiving topotecan to increase the effect of the chemotherapeutic agent.  相似文献   
30.
In this study, the anatomical features of the leaf and stem, besides the pollen and nutlet characteristics of Teucrium sandrasicum are investigated. T. sandrasicum, belonging to sect. Teucrium, is an endemic perennial herb growing on serpentine around Muğla province. The anatomical studies on T. sandrasicum revealed that the stem shares the general characteristics of the Labiatae family. The leaves clearly exhibit xeromorphy due to features such as the distribution of stomata on the lower surface (hipostomatic), the occurrence of guard cells below the epidermis (xeromorphic type), inrolled margins, thick cuticle layer, thick outer epidermal cell wall, a high density of trichomes and thick palisade layer of the mesophyll. The anatomical studies showed that the upper epidermal cells of the leaf include many spherocrystals. The pollen grains are prolate, medium in size, 3-colpate with verrucate ornamentation. The nutlets are ellipsoid with a reticulate-verrucate surface. The results have proven that T. sandrasicum is different from the other species of the sect. Teucrium because of the branched trichomes on the stem and the lack of eglandular trichomes on the nutlets.  相似文献   
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