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101.

Background

Reductions in quality of life (QOL) exist among individuals with multiple sclerosis (MS).

Objective

The present investigation aimed to adopt a biopsychosocial model in examining QOL in the early stages of MS.

Methods

Individuals with MS (34 with average to low QOL and 35 with high QOL) were compared on measures of disease symptoms, psychological functioning, personality, self-efficacy, locus of control (LOC), social support, and coping to determine the most salient predictors of QOL.

Results

Individuals were matched on disease course and duration. Individuals with lower QOL reported more fatigue, sleep problems, pain, depression, and anxiety (d?=?0.83–1.49, p's?<?0.001). They also reported lower levels of self-efficacy, LOC, and social support (d?=?0.75–1.50 p's?<?0.01). They indicated higher levels of neuroticism (d?=?1.31, p?<?.001) and lower levels of extraversion (d?=?1.21, p?<?.001) and reported greater levels of disengagement as a means of coping (d?=?0.75, p?=?.002). Those with high QOL endorsed more use of adaptive coping (d?=?0.52 - 0.86, p's?<?0.05). When taken together, LOC and anxiety were the most significant predictors, accounting for 40% of the variance.

Conclusion

Even early on in the illness, there exists differing levels of QOL. Identifying the psychological and social variables as well as the disease related factors is important, and in this case, may make a much greater contribution. Efforts to assure routine assessment and effective intervention aimed at these factors are warranted, particularly as an early intervention to assure maintenance/improvement in QOL among individuals with MS.  相似文献   
102.
1.?Human cytosolic sulfotransferase 1B1 (SULT1B1) sulfates small phenolic compounds and bioactivates polycyclic aromatic hydrocarbons. To date, no SULT1B1 allelic variants have been well-characterized.

2.?While cloning SULT1B1 from human endometrial specimens, an allelic variant resulting in valine instead of leucine at the 145th amino acid position (L145V) was detected. NCBI reported this alteration as the highest frequency SULT1B1 allelic variant.

3.?L145V frequency comprised 9% of 37 mixed-population human patients and was specific to African Americans with an allelic frequency of 25%. Structurally, replacement of leucine with valine potentially destabilizes a conserved helix (α8) that forms the “floor” of both the substrate and PAPS binding domains. This destabilization results in altered kinetic properties including a four-fold decrease in affinity for PAP (3′, 5′-diphosphoadenosine). Kms for 3′-phosphoadenosine- 5′-phosphosulfate (PAPS) are similar; however, maximal turnover rate of the variant isoform (0.86?pmol/(min*μg)) is slower than wild-type (WT) SULT1B1 (1.26?pmol/(min*μg)). The L145V variant also displays altered kinetics toward small phenolic substrates, including a diminished p-nitrophenol Km and increased susceptibility to 1-naphthol substrate inhibition.

4.?No significant correlation between genotype and prostate or colorectal cancer was observed in patients; however, the variant isoform could underlie specific pathologies in sub-Saharan African carriers.  相似文献   
103.
104.

Purpose

Biotherapeutics can be susceptible to oxidation during manufacturing and storage. Free L-methionine is known to protect methionine residues in proteins from oxidation. Similarly, free tryptophan and other indole derivatives have been shown to protect tryptophan residues from oxidation. N-acetyl-DL-tryptophan was previously identified as a potentially superior antioxidant to tryptophan as it has a lower oxidation potential and produces less peroxide upon light exposure. This study sought to confirm the antioxidant efficacy and safety of N-acetyl-DL-tryptophan and L-methionine as formulation components for biotherapeutic drugs.

Methods

Antibodies were subjected to AAPH and light exposure in the presence of N-acetyl-DL-tryptophan and L-methionine. Oxidation in relevant CDR and Fc residues was quantified by peptide map. In silico, in vitro, and in vivo studies were performed to evaluate the safety of N-acetyl-DL-tryptophan and L-methionine.

Results

Peptide mapping demonstrated that N-acetyl-DL-tryptophan was effective at protecting tryptophans from AAPH stress, and that the combination of N-acetyl-DL-tryptophan and L-methionine protected both tryptophan and methionine from AAPH stress. The safety assessment suggested an acceptable safety profile for both excipients.

Conclusions

N-acetyl-tryptophan and L-methionine effectively reduce the oxidation of susceptible tryptophan and methionine residues in antibodies and are safe for use in parenteral biotherapeutic formulations.
  相似文献   
105.
We demonstrate the coating of tablets using an injection molding (IM) process that has advantage of being solvent free and can provide precision coat features. The selected core tablets comprising 10% w/w griseofulvin were prepared by an integrated hot melt extrusion-injection molding (HME-IM) process. Coating trials were conducted on a vertical injection mold machine. Polyethylene glycol and polyethylene oxide based hot melt extruded coat compositions were used. Tablet coating process feasibility was successfully demonstrated using different coating mold designs (with both overlapping and non-overlapping coatings at the weld) and coat thicknesses of 150 and 300?μm. The resultant coated tablets had acceptable appearance, seal at the weld, and immediate drug release profile (with an acceptable lag time). Since IM is a continuous process, this study opens opportunities to develop HME-IM continuous processes for transforming powder to coated tablets.  相似文献   
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