3 research outputs found
Positron Emission Tomography Assessment of the Intranasal Delivery Route for Orexin A
Intranasal drug delivery is a noninvasive
drug delivery route that
can enhance systemic delivery of therapeutics with poor oral bioavailability
by exploiting the rich microvasculature within the nasal cavity. The
intranasal delivery route has also been targeted as a method for improved
brain uptake of neurotherapeutics, with a goal of harnessing putative,
direct nose-to-brain pathways. Studies in rodents, nonhuman primates,
and humans have pointed to the efficacy of intranasally delivered
neurotherapeutics, while radiolabeling studies have analyzed brain
uptake following intranasal administration. In the present study,
we employed carbon-11 radioactive methylation to assess the pharmacokinetic
mechanism of intranasal delivery of Orexin A, a native neuropeptide
and prospective antinarcoleptic drug that binds the orexin receptor
1. Using physicochemical and pharmacological analysis, we identified
the methylation sites and confirmed the structure and function of
methylated Orexin A (CH<sub>3</sub>-Orexin A) prior to monitoring
its brain uptake following intranasal administration in rodent and
nonhuman primate. Through positron emission tomography (PET) imaging
of [<sup>11</sup>C]ÂCH<sub>3</sub>-Orexin A, we determined that the
brain exposure to Orexin A is poor after intranasal administration.
Additional ex vivo analysis of brain uptake using [<sup>125</sup>I]ÂOrexin
A indicated intranasal administration of Orexin A affords similar
brain uptake when compared to intravenous administration across most
brain regions, with possible increased brain uptake localized to the
olfactory bulbs
Effects of the Adulteration Technique on the Near-Infrared Detection of Melamine in Milk Powder
The United States Pharmacopeial Convention has
led an international collaborative project to develop a toolbox of
screening methods and reference standards for the detection of milk
powder adulteration. During the development of adulterated milk powder
reference standards, blending methods used to combine melamine and
milk had unanticipated strong effects on the near-infrared (NIR) spectrum
of melamine. The prominent absorbance band at 1468 nm of melamine
was retained when it was dry-blended with skim milk powder but disappeared
in wet-blended mixtures, where spray-dried milk powder samples were
prepared from solution. Analyses using polarized light microscopy,
Raman spectroscopy, dielectric relaxation spectroscopy, X-ray diffraction,
and mass spectrometry indicated that wet blending promoted reversible
and early Maillard reactions with lactose that are responsible for
differences in melamine NIR spectra between wet- and dry-blended samples.
Targeted detection estimates based solely on dry-blended reference
standards are likely to overestimate NIR detection capabilities in
wet-blended samples as a result of previously overlooked matrix effects
arising from changes in melamine hydrogen-bonding status, covalent
complexation with lactose, and the lower but more homogeneous melamine
local concentration distribution produced in wet-blended samples.
Techniques used to incorporate potential adulterants can determine
the suitability of milk reference standards for use with rapid detection
methods
Age and frailty are independently associated with increased COVID-19 mortality and increased care needs in survivors: results of an international multi-centre study
Introduction: Increased mortality has been demonstrated in older adults with coronavirus disease 2019 (COVID-19), but the effect of frailty has been unclear.
Methods: This multi-centre cohort study involved patients aged 18 years and older hospitalised with COVID-19, using routinely collected data. We used Cox regression analysis to assess the impact of age, frailty and delirium on the risk of inpatient mortality, adjusting for sex, illness severity, inflammation and co-morbidities. We used ordinal logistic regression analysis to assess the impact of age, Clinical Frailty Scale (CFS) and delirium on risk of increased care requirements on discharge, adjusting for the same variables.
Results: Data from 5,711 patients from 55 hospitals in 12 countries were included (median age 74, interquartile range [IQR] 54–83; 55.2% male). The risk of death increased independently with increasing age (>80 versus 18–49: hazard ratio [HR] 3.57, confidence interval [CI] 2.54–5.02), frailty (CFS 8 versus 1–3: HR 3.03, CI 2.29–4.00) inflammation, renal disease, cardiovascular disease and cancer, but not delirium. Age, frailty (CFS 7 versus 1–3: odds ratio 7.00, CI 5.27–9.32), delirium, dementia and mental health diagnoses were all associated with increased risk of higher care needs on discharge. The likelihood of adverse outcomes increased across all grades of CFS from 4 to 9.
Conclusion: Age and frailty are independently associated with adverse outcomes in COVID-19. Risk of increased care needs was also increased in survivors of COVID-19 with frailty or older age.</p