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91.
Nodular basal cell carcinoma is a deep skin lesion and one of the most common cancers. Conventional photodynamic therapy is limited to treatment of superficial skin lesions. The parenteral administration of near-IR preformed photosensitizers suffers from poor selectivity and may result in prolonged skin photosensitivity. Microneedles (MNs) can provide localized drug delivery to skin lesions. Intradermal delivery of the preformed near-IR photosensitizer; 5,10,15,20-tetrakis(2,6-difluoro-3-N-methylsulfamoylphenyl bacteriochlorin (Redaporfin?) using dissolving MN was successful in vitro and in vivo. MN demonstrated complete dissolution 30 min after skin application and showed sufficient mechanical strength to penetrate the skin to a depth of 450 μm. In vitro deposition studies illustrated that the drug was delivered and detected down to 5 mm in skin. In vivo biodistribution studies in athymic nude mice Crl:NU(NCr)-Foxn1nu showed both fast initial release and localized drug delivery. The MN-treated mice showed a progressive decrease in the fluorescence intensity at the application site over the 7-day experiment period, with the highest and lowest fluorescence intensities measured being 9.2 × 1010 ± 2.5 × 1010 and 3.8 × 109 ± 1.6 × 109 p/s, respectively. By day 7, there was some migration of fluorescence away from the site of initial MN application. However, the majority of the body surfaces showed fluorescence levels that were comparable to those seen in the negative control group. This work suggests utility for polymeric MN arrays in minimally invasive intradermal delivery to enhance photodynamic therapy of deep skin lesions.  相似文献   
92.
We have used hydrogen exchange–mass spectrometry to characterize local backbone flexibility of 4 well-defined IgG1-Fc glycoforms expressed and purified from Pichia pastoris, 2 of which were prepared using subsequent in vitro enzymatic treatments. Progressively decreasing the size of the N-linked N297 oligosaccharide from high mannose (Man8-Man12), to Man5, to GlcNAc, to nonglycosylated N297Q resulted in progressive increases in backbone flexibility. Comparison of these results with recently published physicochemical stability and Fcγ receptor binding data with the same set of glycoproteins provide improved insights into correlations between glycan structure and these pharmaceutical properties. Flexibility significantly increased upon glycan truncation in 2 potential aggregation-prone regions. In addition, a correlation was established between increased local backbone flexibility and increased deamidation at asparagine 315. Interestingly, the opposite trend was observed for oxidation of tryptophan 277 where faster oxidation correlated with decreased local backbone flexibility. Finally, a trend of increasing C'E glycopeptide loop flexibility with decreasing glycan size was observed that correlates with their FcγRIIIa receptor binding properties. These well-defined IgG1-Fc glycoforms serve as a useful model system to identify physicochemical stability and local backbone flexibility data sets potentially discriminating between various IgG glycoforms for potential applicability to future comparability or biosimilarity assessments.  相似文献   
93.
Administration of local anesthetics is one of the most effective pain control techniques for postoperative analgesia. However, anesthetic agents easily diffuse into the injection site, limiting the time of anesthesia. One approach to prolong analgesia is to entrap local anesthetic agents in nanostructured carriers (e.g., liposomes). Here, we report that using an ammonium sulphate gradient was the best strategy to improve the encapsulation (62.6%) of dibucaine (DBC) into liposomes. Light scattering and nanotracking analyses were used to characterize vesicle properties, such as, size, polydispersity, zeta potentials, and number. In vitro kinetic experiments revealed the sustained release of DBC (50% in 7 h) from the liposomes. In addition, in vitro (3T3 cells in culture) and in vivo (zebrafish) toxicity assays revealed that ionic-gradient liposomes were able to reduce DBC cyto/cardiotoxicity and morphological changes in zebrafish larvae. Moreover, the anesthesia time attained after infiltrative administration in mice was longer with encapsulated DBC (27 h) than that with free DBC (11 h), at 320 μM (0.012%), confirming it as a promising long-acting liposome formulation for parenteral drug administration of DBC.  相似文献   
94.
We assessed the relationships among HIV-related social and behavioral outcomes resulting from an adolescent-focused HIV structural change initiative in eight urban sites operating Connect-to-Protect coalitions. Over a 4-year period, annual cross-sectional panels of adolescents (N = 2248) completed an audio-computer-assisted interview, providing data on satisfaction with their communities as adolescent-supportive environments, internalized HIV stigma, lifetime HIV-testing, lifetime sexual risk-taking and number of sexual partners in the prior year. We used structural equation modeling to estimate hypothesized links between time since coalition mobilization to our social and behavioral outcomes. Over the 4 years, adolescents perceived their communities to become more supportive (p < .05). Positive perceptions of community support were associated with lower lifetime HIV sexual risk (p < .05). The effect of time on risk behavior was mediated by perceptions of community support. Stigma was unchanged over time. Stigma had damaging effects on risk behavior, effects which were also mediated by perceptions of community support. Special efforts are needed to address the deleterious effect of HIV stigma on high-risk urban adolescents.  相似文献   
95.

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   
96.
Smoking is much more common among persons with behavioral health conditions (mental illnesses and/or substance use disorders). Persons with these disorders are more likely to die from smoking-related causes than any other reason. Studies have shown that stopping smoking can improve mental health function, as well as improve outcomes for substance use disorders. Yet, for a variety of reasons, smoking cessation has not been integrated into the treatment of behavioral health conditions, and in many instances tobacco use was not only condoned but encouraged. Beginning in 2007, the Smoking Cessation Leadership Center (SCLC) began engaging relevant agencies in an attempt to stimulate more vigorous smoking cessation activities. Partners included the federal Substance Abuse and Mental Health Services Administration, advocacy organizations such as the National Alliance on Mental Illness and Community Anti-Drug Coalitions of America, and clinical groups such as the American Psychiatric Nurses Association, the American Psychiatric Association, American Psychological Association, National Council on Behavioral Health, and National Association of State Mental Health Program Directors. A signature program featured 16 individual state summits involving agencies and groups from multiple sectors, all aiming to lower smoking rates in behavioral health populations. These activities mark an evolving culture change within behavioral health.  相似文献   
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