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51.
Cyclic neutropenia is a rare hematologic disorder, characterized by repetitive episodes of fever, mouth ulcers, and infections attributable to recurrent severe neutropenia. Fluctuations in blood cells are due to oscillatory production of cells by the bone marrow. Recent genetic, molecular, and cellular studies have shown that autosomal-dominant cyclic neutropenia and sporadic cases of this disease are due to a mutation in the gene for neutrophil elastase (ELA2), located at 19p13.3. This enzyme is synthesized in neutrophil precursors early in the process of primary granule formation. It is currently presumed that the mutant neutrophil elastase functions aberrantly within the cells to accelerate apoptosis of the precursors, resulting in effective and oscillatory production. Cyclic neutropenia is effectively treated with granulocyte colony-stimulating factor (G-CSF), usually at doses of 1 to 5 microg/kg/d (median dose, 2.5 microg/kg/d). Long-term, daily, or alternate-day administration reduces fever, mouth ulcers, and other inflammatory events associated with this disorder. Leukemic transformation is not a recognized risk for cyclic neutropenia, with or without treatment with G-CSF.  相似文献   
52.
The evolution of instrumentation in terms of separation and detection allowed a real improvement of the sensitivity and analysis time. However, the analysis of ultra-traces of toxins in complex samples requires often a step of purification and even preconcentration before their chromatographic analysis. Therefore, immunoaffinity sorbents based on specific antibodies thus providing a molecular recognition mechanism appear as powerful tools for the selective extraction of a target molecule and its structural analogs to obtain more reliable and sensitive quantitative analysis in environmental, food or biological matrices. This review focuses on immunosorbents that have proven their efficiency in selectively extracting various types of toxins of various sizes (from small mycotoxins to large proteins) and physicochemical properties. Immunosorbents are now commercially available, and their use has been validated for numerous applications. The wide variety of samples to be analyzed, as well as extraction conditions and their impact on extraction yields, is discussed. In addition, their potential for purification and thus suppression of matrix effects, responsible for quantification problems especially in mass spectrometry, is presented. Due to their similar properties, molecularly imprinted polymers and aptamer-based sorbents that appear to be an interesting alternative to antibodies are also briefly addressed by comparing their potential with that of immunosorbents.  相似文献   
53.
We report herein a case of blastoid variant mantle cell lymphoma (MCL) with both aberrant phenotype and unusual genetics. Unexpectedly, lymphoma cells were CD5 and CD10+. Standard karyotype and FISH techniques showed that tumor cells carried two distinct translocations which had not been reported together in a same tumor. The first translocation juxtaposed the immunoglobulin lambda light chain locus with CCND1 locus, leading to Cyclin D1 overexpression. The second translocation revealed MYC rearrangement with a non-immunoglobulin gene partner located on the short arm of chromosome 4. The interpretation of the case on tissue sections alone could have been challenging. Indeed, the lack of CD5 and expression of CD10 associated with MYC rearrangement detected on interphasic nuclei could support the diagnosis of diffuse large B-cell lymphoma or Burkitt lymphoma. This distinction is also especially important as these lymphoma subtypes require specific treatment.  相似文献   
54.

Objective

Newborn screening (NBS) identifies genetic carriers for sickle cell hemoglobinopathy and cystic fibrosis. We aimed to identify factors during initial NBS carrier results disclosure by primary care providers (PCPs) that influenced parents’ experiences and reactions.

Methods

Open-ended responses from telephone interviews with 270 parents of carriers were analyzed using mixed-methods. Conventional content analysis identified influential factors; chi-square tests analyzed relationships between factors and parent-reported reactions.

Results

Parents reported positive (35%) or negative (31%) reactions to results disclosure. Parents’ experiences were influenced by specific factors: content messages (72%), PCP traits (47%), and aspects of the setting (30%). Including at least one of five specific content messages was associated (p < 0.05) with positive parental reactions; omitting at least one of four specific content messages was associated (p < 0.05) with negative parental reactions. Parents reported positive reactions when PCPs avoided jargon or were perceived as calm. Parents reported negative reactions to jargon usage and results disclosure by voicemail.

Conclusion

Parents identified aspects of PCP communication which influenced their reactions and results disclosure experiences.

Practice implications

Our findings suggest ways PCPs may improve communication of carrier results. PCPs should provide specific content messages and consider how their actions, characteristics, and setting can influence parental reactions.  相似文献   
55.
European Journal of Clinical Microbiology & Infectious Diseases - Molecular diagnosis on nasopharyngeal swabs (NPS) is the current standard for COVID-19 diagnosis, but saliva may be an...  相似文献   
56.

Purpose

It has been demonstrated that exercise-induced dehydration (EID) does not impair, and ad libitum drinking optimizes, cycling time-trial (TT) performance. However, the idea that EID ≥ 2 % bodyweight (BW) impairs endurance performance is well ingrained. No study has tested the impact of EID upon running TT performance. We compared the effects of thirst-driven (TD) vs. programmed fluid intake (PFI) aimed at maintaining EID-associated BW loss <2 % on half-marathon performance.

Methods

Ten trained distance runners underwent, in a randomized, crossover fashion, two, 21.1 km running TTs on a treadmill (30 °C, 42 % relative humidity) while facing a wind speed matching running speed and drinking water (1) according to thirst sensation (TD) or (2) to maintain BW loss <2 % of their pre-exercise BW (PFI), as recommended by the American College of Sports Medicine.

Results

Despite that PFI significantly reduced EID from 3.1 ± 0.6 (TD) to 1.3 ± 0.7 % BW (PFI), mean rectal temperature from 39.4 ± 0.4 to 39.1 ± 0.3 °C, mean body temperature from 38.1 ± 0.4 to 37.7 ± 0.2 °C and mean heart rate from 175 ± 9 to 171 ± 8 bpm, neither half-marathon time (TD 89.8 ± 7.7; PFI 89.6 ± 7.7 min) nor running pace (TD 4.3 ± 0.4; PFI 4.2 ± 0.4 min/km) differed significantly between trials.

Conclusion

Albeit providing trivial cardiovascular and thermoregulatory advantages, in trained distance runners, PFI (1,380 ± 320 mL/h) offers no performance benefits over TD fluid intake (384 ± 180 mL/h) during a half-marathon raced under warm conditions.  相似文献   
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Malaria and HIV infection are coendemic in a large portion of the world and remain a major cause of morbidity and mortality. Growing resistance of Plasmodium species to existing therapies has increased the need for new therapeutic approaches. The Plasmodium glucose transporter PfHT is known to be essential for parasite growth and survival. We have previously shown that HIV protease inhibitors (PIs) act as antagonists of mammalian glucose transporters. While the PI lopinavir is known to have antimalarial activity, the mechanism of action is unknown. We report here that lopinavir blocks glucose uptake into isolated malaria parasites at therapeutically relevant drug levels. Malaria parasites depend on a constant supply of glucose as their primary source of energy, and decreasing the available concentration of glucose leads to parasite death. We identified the malarial glucose transporter PfHT as a target for inhibition by lopinavir that leads to parasite death. This discovery provides a mechanistic basis for the antimalarial effect of lopinavir and provides a direct target for novel drug design with utility beyond the HIV-infected population.  相似文献   
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