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81.

We evaluated the long-term serological follow-up of patients with vascular risk factors for chronic Q fever that were previously Coxiella burnetii seropositive. C. burnetii phase I IgG titers were reevaluated in patients that gave informed consent or retrospectively collected in patients already deceased or lost to follow-up. Of 107 patients, 25 (23.4%) became seronegative, 77 (72.0%) retained a profile of past resolved Q fever infection, and five (4.7%) developed chronic Q fever. We urge clinicians to stay vigilant for chronic Q fever beyond two years after primary infection and perform serological testing based on clinical presentation.

  相似文献   
82.
Fanconi anemia (FA) is a rare genetic disorder characterized by congenital malformations, progressive bone marrow failure (BMF), and susceptibility to malignancies. FA is caused by biallelic or hemizygous mutations in one of 15 known FA genes, whose products are involved in the FA/BRCA DNA damage response pathway. Here, we report on a patient with previously unknown mutations of the most recently identified FA gene, SLX4/FANCP. Whole exome sequencing (WES) revealed a nonsense mutation and an unusual splice site mutation resulting in the partial replacement of exonic with intronic bases, thereby removing a nuclear localization signal. Immunoblotting detected no residual SLX4 protein, which was consistent with abrogated interactions with XPF/ERCC1 and MUS81/EME1. This cellular finding did not result in a more severe clinical phenotype than that of previously reported FA‐P patients. Our study additionally exemplifies the versatility of WES for the detection of mutations in heterogenic disorders such as FA.  相似文献   
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Background

Although pain is frequently experienced by patients with cancer, it remains under-treated. The primary aim of this study was to estimate the prevalence of cancer-related neuropathic pain (CRNP) in patients with chronic pain who attended an outpatient clinic for standard care in Europe (irrespective of the reason or stage of the cancer). The secondary aims of this study were to characterise pain and cancer in patients with CRNP (including treatment) and to evaluate the usefulness of the painDETECT (PD-Q) screening tool to help physicians identify a potential neuropathic component of cancer-related pain.

Methods

An observational, non-interventional, cross-sectional, multi-centre study of adult patients with cancer using patient and physician case report forms (CRFs). Patients with CRNP were identified by physicians’ clinical assessments after examining the completed PD-Q.

Results

A total of 951 patients visiting outpatient clinics across Europe were enrolled in this study between August 2010 and July 2011. Of these, 310 patients (32.60%; 95% confidence interval 29.62, 35.58) were identified as having CRNP. Twenty-nine of 39 (74.4%) physicians who completed the CRF relating to the PD-Q considered it a useful tool to help detect CRNP in daily practice and 28 of 39 (71.8%) indicated that they would use this tool in the future for most or some of their patients. Data from physicians before and after review of the completed PD-Qs showed a shift in clinical opinion (either to positive CRNP diagnosis [yes] or negative CRNP diagnosis [no]) in respect of 142 patients; about half of which (74) were categorised with an initial diagnosis of unknown. Opinions also shifted from a no to a yes diagnosis in 10 patients and from a yes to a no diagnosis in 51 patients.

Conclusions

Approximately one-third of adults with cancer experiencing chronic pain attending outpatient clinics as part of routine care were considered to have CRNP in the opinion of the physicians after considering scores on the PD-Q. While physicians did not consider the PD-Q to be a useful tool for all patients, shifts in diagnosis before and after the use of this tool indicate that it may help physicians identify CRNP, especially where there is initial uncertainty.
  相似文献   
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A water-soluble extract of Nocardia markedly increased in vitro [(3)H]thymidine incorporation by mouse spleen lymphocytes. The blastogenic activity of the extract and lipopolysaccharide was studied comparatively on various mouse lymphocyte subpopulations. The data obtained by [(3)H]thymidine incorporation and by electron microscopy have demonstrated that this preparation stimulates selectively mouse bone-marrow-derived cortisone-sensitive lymphocytes. This stimulation is related neither to a natural infection of mice with Nocardia organisms nor to the presence in Nocardia water-soluble mitogen of a lipopolysaccharide contaminant or of a lipopolysaccharide-like material.  相似文献   
88.
Dendritic cells (DCs), the mononuclear cells that initiate immune response, and osteoclasts, the multinucleated bone-resorbing cells, are derived from monocyte/macrophage precursor cells. Granulocyte-macrophage colony-stimulating factor and macrophage colony-stimulating factor (M-CSF) reciprocally regulate the differentiation of both lineages in mice. Using human monocyte-derived DCs generated in vitro, we show that immature DCs transdifferentiate into functional osteoclasts (OCs) in the presence of M-CSF and receptor activator of nuclear factor-kappaB ligand (RANKL). Transdifferentiation operates through fusion of intermediate adherent bipolar fusiform mononuclear cells expressing CD14, CD1a, and RANKL and able to induce RANKL(+) T-cell proliferation. Surprisingly, DC fusion in vitro is faster and more efficient than monocyte fusion to form multinucleated giant cells. The transdifferentiation process reported here supports the existence of a high cellular plasticity within differentiated myeloid phagocytes. Importantly, this process is greatly enhanced by rheumatoid arthritis synovial fluid and involves proinflammatory cytokines such as interleukin 1 or tumor necrosis factor alpha, as well as components of the extracellular matrix such as hyaluronic acid. Our data therefore suggest that DC-derived OCs may be directly involved in the osteolytic lesions observed in human inflammatory bone diseases such as rheumatoid arthritis or in particular forms of Langerhans cell histiocytosis, characterized by accumulation of immature skin DCs and chronic lytic bone lesions.  相似文献   
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Location of Ribosomal Protein Binding Sites on 16S Ribosomal RNA   总被引:13,自引:4,他引:13       下载免费PDF全文
The distribution of ribosomal protein binding sites on the 16S ribosomal RNA molecule has been analyzed by limited ribonuclease hydrolysis of RNA-protein complexes, as well as by the interaction of individual proteins with RNA fragments purified from partial enzymatic digests. Of the six 30S subunit proteins known to interact directly with 16S RNA, proteins S4, S8, S15, S20, and, probably, S13 bind within a fragment produced by T(1) RNase (12S RNA) that comprises some 900 nucleotides and covers almost the entire 5'-terminal half of the 16S molecule. A fragment of 500-600 nucleotides (8S RNA) that is contiguous with 12S RNA and arises from the 3'-terminal portion of the 16S molecule is believed to contain the binding site for protein S7. Protein S15 interacts specifically with a sequence of about 135 nucleotides (4S RNA) that derives from 12S RNA after more extensive hydrolysis. Protein S4, but none of the other ribosomal proteins, binds to a 500-nucleotide fragment (9S RNA), generated by pancreatic RNase, that lies at the 5'-terminus of 16S RNA and is completely overlapped by the 12S fragment. A preliminary map of the binding sites is presented.  相似文献   
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