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991.
The releases of polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/Fs) from waste incinerators and thermal processes were investigated. The characteristics of mean PCDD/Fs I-TEQ concentrations and congener profiles were studied over the samples of water, soil, fly ash and bottom ash of individual source. The TEQ value for fly ash ranges from 0.013 to 17.01 pg-TEQ/g. Moreover, the TEQ value for bottom ash was 12.06 pg-TEQ/g and the TEQ values for the water samples were found to be in a consistent range from 0.41-0.56 ng-TEQ/L. In almost all the analyzed matrices the congener OCDD/OCDF was found in highest concentration raising the critical concerns over the overall PCDD/Fs emissions from incinerations and thermal processes.  相似文献   
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Planned healthcare transition, initiated in pediatric care, is a gradual process aimed at fostering the adolescent patient’s disease knowledge and skills with the ultimate objective of preparing patients and families for adult-centered care. The process is critical in inflammatory bowel diseases (IBD) where there is an increased risk of non-adherence, hospitalizations, and emergency department use as young adult patients graduate from pediatric to adult-centered care. While evidence for healthcare transition in IBD is mounting, important gaps remain in the understanding of this process from the perspective of the adult gastroenterologist. This paper summarizes what is known about healthcare transition in IBD and explores the unanswered questions—a conceptual and methodological framework for transition interventions, relevant outcomes that define successful transition, and key stakeholder perspectives. For the adult gastroenterologist managing the young adult patient population, this paper presents the paradigm of “care integration”—a process of ongoing, multi-modality support for the patient, initiated in the adult care setting, with the goal of improving self-management skills and active participation in medical decision-making.  相似文献   
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Hematopoietic prostaglandin D(2) synthase (hPGD(2)S) metabolizes cyclooxygenase-derived prostaglandin (PG) H(2) to PGD(2), which is dehydrated to cyclopentenone PGs, including 15-deoxy-Delta(12,14)-PGJ(2) (15d-PGJ(2)). PGD(2) acts through two receptors (DP1 and DP2/CRTH2), whereas 15d-PGJ(2) can activate peroxisome proliferator-activated receptors or inhibit a range of proinflammatory signaling pathways, including NF-kappaB. Despite eliciting asthmatic and allergic reactions through the generation of PGD(2), it is not known what role hPGD(2)S plays in T helper (Th)1-driven adaptive immunity. To investigate this question, the severity and duration of a delayed type hypersensitivity reaction was examined in hPGD(2)S knockout and transgenic mice. Compared with their respective controls, knockouts displayed a more severe inflammatory response that failed to resolve, characterized histologically as persistent acute inflammation, whereas transgenic mice had little detectable inflammation. Lymphocytes isolated from inguinal lymph nodes of hPGD(2)S(-/-) animals showed hyperproliferation and increased IL-2 synthesis effects that were rescued by 15d-PGJ(2), but not PGD(2), working through either of its receptors. Crucially, 15d-PGJ(2) exerted its suppressive effects through the inhibition of NF-kappaB activation and not through peroxisome proliferator-activated receptor signaling. In contrast, lymph node cultures from transgenics proliferated more slowly and synthesized significantly less IL-2 than controls. Therefore, contrary to its role in driving Th2-like responses, this report shows that hPGD(2)S may act as an internal braking signal essential for bringing about the resolution of Th1-driven delayed type hypersensitivity reactions. Consequently, hPGD(2)S-derived cyclopentenone PGs may protect against inflammatory diseases, where T lymphocytes play a pathogenic role, as in rheumatoid arthritis, atopic eczema, and chronic rejection.  相似文献   
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Background

Ring chromosome 6 (r(6)) is a rare disorder that mainly occurs as a ‘de novo’ event. Nonetheless, a wide phenotypic spectrum has been reported in r(6) cases, depending on breakpoints, size of involved region, copy number alterations and mosaicism of cells with r(6) and/or monosomy 6 due to loss of r(6).

Case presentation

An 11-year-old male was referred with developmental delay, intellectual disability and microcephaly. Physical examination revealed additionally short stature and multiple facial dysmorphisms. Banding cytogenetic studies revealed a karyotype of mos 46,XY,r(6)(p25.3q27)[54]/45,XY,-6[13]/46,XY,r(6)(::p25.3→q27::p25.3→q27::)[13]/46,XY[6]/47,XY,r(6)(p25.3q27)×2[2]dn. Additionally, molecular karyotyping and molecular cytogenetics confirmed the breakpoints and characterized a 1.3 Mb contiguous duplication at 6p25.3.

Conclusion

The present study has accurately identified copy number alterations caused by ring chromosome formation. A review of the literature suggests that hemizygous expression of TBP gene in 6q27~qter, is likely to be the underlying cause of the phenotype. The phenotypic correlation and clinical severity in r(6) cases continue to remain widely diverse in spite of numerous reports of genomic variations.
  相似文献   
996.
Periodic paralyses (PPs) are rare neuromuscular disorders caused by mutations in skeletal muscle sodium, calcium, and potassium channel genes. PPs include hypokalemic paralysis, hyperkalemic paralysis, and Andersen‐Tawil syndrome. Common features of PP include autosomal dominant inheritance, onset typically in the first or second decades, episodic attacks of flaccid weakness, which are often triggered by diet or rest after exercise. Diagnosis is based on the characteristic clinic presentation then confirmed by genetic testing. In the absence of an identified genetic mutation, documented low or high potassium levels during attacks or a decrement on long exercise testing support diagnosis. The treatment approach should include both management of acute attacks and prevention of attacks. Treatments include behavioral interventions directed at avoidance of triggers, modification of potassium levels, diuretics, and carbonic anhydrase inhibitors. Muscle Nerve 57 : 522–530, 2018  相似文献   
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