Viet Q. Nguyen

Comparison of satisfaction with current prosthetic care in veterans and servicemembers from Vietnam and OIF/OEF conflicts with major traumatic limb loss

Prosthetic care is a vital aspect of healthcare and rehabilitation for veterans and servicemembers with major traumatic limb loss. Our survey queried 581 veterans and servicemembers with limb loss from the Vietnam and Operation Iraqi Freedom (OIF)/Operation Enduring Freedom (OEF) conflicts. Among survey participants, 78.2% from the Vietnam conflict and 90.5% from the OIF/OEF conflict currently use prosthetic devices. In Vietnam respondents, 78% received prosthetic care from private sources, 16% from Department of Veterans Affairs (VA) prosthetic laboratories, 0.9% from Department of Defense (DOD), and 5% from multiple sources. In OIF/OEF respondents, 42% received prosthetic care from private sources, 9% percent from VA, 39% from DOD, and 10% from multiple sources. Participants identified their satisfaction with current prosthetic devices and prosthetic services. Reports of pain, sweating, skin irritation, and problems with socket fit continue to be significant issues for participants from both conflicts regardless of level of amputation or site of service. In those with upper-limb loss who used myoelectric prostheses, minimal effect on prosthesis use and satisfaction was noted. Among lower-limb loss participants from both conflicts, notable differences existed in prosthesis satisfaction by source of care.

Protonation Sites in Gaseous Pyrrole and Imidazole: A Neutralization–Reionization and ab initio Study

Mild gas-phase acids C4H9+ and NH4+ protonate pyrrole at C-2 and C-3 but not at the nitrogen atom, as determined by deuterium labeling and neutralization-reionization mass spectrometry. Proton affinities in pyrrole are calculated by MP2/6-311G(2d,p) as 866, 845 and 786 kJ mol-1 for protonation at C-2, C-3 and N, respectively. Vertical neutralization of protonated pyrrole generates bound radicals that in part dissociate by loss of hydrogen atoms. Unimolecular loss of hydrogen atom from C-2- and C-3-protonated pyrrole cations is preceded by proton migration in the ring. Protonation of gaseous imidazole is predicted to occur exclusively at the N-3 imine nitrogen to yield a stable aromatic cation. Proton affinities in imidazole are calculated as 941, 804, 791, 791 and 724 for the N-3, C-4, C-2, C-5 and N-1 positions, respectively. Radicals derived from protonated imidazole are only weakly bound. Vertical neutralization of N-3-protonated imidazole is accompanied by large Franck-Condon effects which deposit on average 183 kJ mol-1 vibrational energy in the radicals formed. The radicals dissociate unimolecularly by loss of hydrogen atom, which involves both direct N-H bond cleavage and isomerization to the more stable C-2 H-isomer. Potential energy barriers to isomerizations and dissociations in protonated pyrrole and imidazole isomers and their radicals were investigated by ab initio calculations.

Midlife use of written Japanese and protection from late life dementia

Background: The cognitive reserve hypothesis would predict that use of written Japanese should confer protection against dementia because of the complexity of its ideograms compared with written English. We sought to test this hypothesis in analyses from a longitudinal study of Japanese-American men. Methods: Participants were second-generation Japanese-American men (Nisei) on the island of Oahu, Hawaii, who were seen in 1965 and in subsequent examinations to detect dementia beginning in 1991–1993. Use of spoken and written Japanese was self-reported in 1965 (Analyses 1 and 2), and midlife use of written Japanese and written English was self-reported in 1994–1996 (Analysis 3). We analyzed prevalent dementia outcomes in 1991–1993 (Analysis 1, n = 3139) using logistic regression, and incident dementia outcomes in 1994–2002 (Analysis 2, n = 2299) and in 1997–2002 (Analysis 3, n = 1655) using Cox proportional hazards regression. Dementia outcomes included all-cause dementia, probable and possible Alzheimer disease, and probable vascular dementia. We adjusted models for probable and possible confounders. Results: Participants who reported proficiency with written Japanese were older and had lower incomes. For Analysis 1, there were 154 prevalent cases of dementia, 74 of Alzheimer disease, and 43 of vascular dementia; for Analysis 2, 236 incident cases of dementia, 138 of Alzheimer disease, and 45 of vascular dementia; and for Analysis 3, 125 incident cases of dementia, 80 of Alzheimer disease, and 20 of vascular dementia. There was no relationship in adjusted models between self-reported proficiency with written Japanese and any dementia outcomes. Conclusions: Proficiency with written Japanese does not appear to be protective for dementia.

Energy effects in collisional neutralization with organic molecules.

Neutralization-reionization of CH3OH+., CH3NH2+. and (CH3)2NH+. ions was studied under conditions of exothermic and endothermic electron transfer and distributions of internal energy in the reionized ions were determined. The internal energy deposited on neutralization at kiloelectronvolt collision energies is governed by Franck-Condon effects for the systems under study, whereas the endothermic or exothermic energy balance in electron transfer from molecular targets has only a small effect on the high-energy fraction of the molecules formed. Electron transfer from low-lying molecular orbitals of the organic donor is suggested to occur during random orientations of the ion-molecule collision pair. The internal energy of the precursor ions to be neutralized has a large effect on the relative abundances of survivor ions in the spectra. Vertical recombination energies of CH3OH+. and CH3NH2+. are found by Gaussian-2 level calculations to differ substantially from vertical ionization energies of the corresponding neutral molecules. Franck-Condon effects are analyzed for the vibrational modes that are affected most by vertical electron transfer.

Gas‐phase Protonation of Pyridine. A Variable‐time Neutralization–Reionization andAb InitioStudy of Pyridinium Radicals

Gas-phase protonation of pyridine with CH3NH3+, NH4+, t-C4H9+, H3O+ and CH5+ under thermal conditions was studied by variable-time neutralization-reionization mass spectrometry and ab initio calculations. N-Protonation was found to occur exclusively for CH3NH3+ through H3O+ and predominantly for CH5+. The calculated MP2/6-311G(2d,p) energies gave the proton affinities of N, C-2, C-3 and C-4 in pyridine as 924, 658, 686 and 637 kJ mol-1, respectively, which were in good agreement with previous experimental and theoretical results. Vertical neutralization of the N-protonated isomer (1H+) was accompanied by moderate Franck-Condon effects that deposited 20-21 kJ mol-1 in the 1H-pyridinium radicals (1H) formed. 1H was calculated by UMP2/6-311G(2d,p) and B3LYP/6-311G(2d,p) to be a bound species in its ground electronic state. A substantial fraction of stable 1H was detected in the spectra, which depended on the precursor ion internal energy. Deuterium labeling showed a specific loss of the N-bound hydrogen or deuterium in the radicals. The specificity increased with increasing internal energy in the radicals and decreasing contribution of ion dissociations following reionization. Variable-time measurements established specific loss of the N-bound deuterium also in dissociating low-energy 1D. Loss of hydrogen from 1H+ cations following reionization was highly endothermic and was accompanied by rearrangements that partially scrambled the ring hydrogens.

Guideline concordant venous ulcer care predicts healing in a tertiary care Veterans Affairs Medical Center.

This study describes the impact of 80% adherence to guideline concordant care for compression therapy, moist wound‐healing environment, and debridement on venous ulcer outcomes. The retrospective cohort design included patients from a tertiary care Veterans Affairs Medical Center from October 2003 to September 2007. During this 5‐year interval, 155 patients with 400 venous ulcers met study inclusion. A majority of ulcers (n=362) healed, with an average time to healing of 18.1 weeks (range 2–209 weeks, median 10.4 weeks). From the multivariate Poisson regression, the likelihood of ulcer healing increased when compression therapy was provided during at least 80% of visits (relative risk [RR], 1.93; 95% confidence interval [CI], 1.27–2.92) or when a moist wound‐healing environment was provided during at least 80% of visits (RR, 1.63; 95% CI, 1.09–2.42). Debridement alone was not significantly associated with ulcer healing (RR, 1.0; 95% CI, 0.61–1.64). Patients who received all three treatments during at least 80% of their visits were more likely to heal than those who received < 80% treatment (RR, 2.52; 95% CI, 1.53–4.16). Guideline concordant venous ulcer care was significantly associated with venous ulcer healing, when provided at 80% or more of patient visits.

Bond dissociations in hypervalent ammonium radicals prepared by collisional neutralization of protonated six‐membered nitrogen heterocycles

Hypervalent organic ammonium radicals were generated by collisional neutralization with dimethyl disulfide of protonated 1,4-diazabicyclo[2.2.2]octane (1H+), N,N′-dimethylpiperazine (2H+) and N-methylpiperazine (3H+). The radicals dissociated completely on the 5.1 μs time-scale. Radical 1H• underwent competitive N−H and N−C bond dissociations producing 1,4-diazabicyclo[2.2.2]octane and small ring fragments. Dissociations of radical 2H• proceeded by N−H bond dissociation and ring cleavage, whereas N−CH3 bond cleavage was less frequent. Radical 3H• underwent N−H, N−CH3 and N−Cring bond cleavages followed by post-reionization dissociations of the formed cations. The pattern of bond dissociations in the hypervalent ammonium radicals derived from six-membered nitrogen heterocycles is similar to those of aliphatic ammonium radicals.

O1-01-04: Midlife proficiency with written Japanese and late life dementia risk among Japanese-American men. The Honolulu-Asia aging study

was to investigate the possible effect modification of the apoE e4 allele for several lifestyle related risk factors for dementia and AD. Methods: Participants of the Cardiovascular Risk Factors, Aging, and Dementia (CAIDE) study were derived from random, population-based samples previously studied in 1972, 1977, 1982, or 1987. After an average follow-up of 21 years, 1449 (73%) aged 65 to 79 years were reexamined in 1998. Results: The apoE e4 allele was an independent risk factor for dementia even after adjustments for lifestyle and vascular factors (OR 2.83, 95% CI 1.61-4.97). Physical inactivity, alcohol drinking, and smoking at midlife increased the risk of dementia and AD particularly among the apoE e4 carriers. Further, among the apoE e4 carriers low to moderate dietary intake of polyunsaturated fats at midlife, as well as moderate to high intake of saturated fats were associated with increased risk of dementia and AD. Also the summarized effect of the lifestyle related factors was more pronounced among the apoE e4 carriers. Conclusions: Physical inactivity, dietary fat intake, alcohol drinking, and smoking at midlife are associated with the risk of dementia and AD, especially among the apoE e4 carriers. The apoE e4 carriers may be more vulnerable for various lifestyle related factors. Thus, especially the carriers of the apoE e4 allele might benefit from adopting a healthy and moderate lifestyle.

42 ACCULTURATION AND ALZHEIMER DISEASE RISK AMONG JAPANESE-AMERICAN ELDERLY: THE KAME STUDY.

Background Cross-cultural studies of Alzheimer disease (AD) in genetically similar populations have been designed to detect possible environmental risk factors. It may be possible to perform similar analyses on a single population by examining acculturation, which is the extent to which individuals moving into a host society adapt to changes in lifestyle. Our objective was to determine whether acculturation to Western society was a risk factor for developing AD in an elderly population of Japanese-Americans. Study Design and Methods A cohort of 1,622 dementia-free individuals with baseline acculturation scores was followed for 8 years with biennial cognitive screening assessments using the Cognitive Abilities Screening Instrument. Individuals scoring < 88 were given a full physical and neuropsychological evaluation. Diagnoses of dementia and AD were obtained by consensus agreement using criteria from the Diagnostic and Statistical Manual of Mental Disorders, 4th edition. Item response theory was used to combine 20 questionnaire responses to generate acculturation scores. Scores were divided into quartiles for analysis. Hazard ratios were calculated using the Cox proportional hazards model to determine the risk of AD for participants in high quartiles of acculturation versus those in low quartiles. We adjusted models for cardiovascular disease risk factors and demographic characteristics such as primary language and income. Results In unadjusted models, the relative hazard associated with higher levels of acculturation was 0.6 (95% CI 0.4-0.97). With adjustments for demographic characteristics, the relative hazard associated with higher levels of acculturation was 1.84 (95% CI 0.5-6.6). With further adjustments for vascular disease risk factors and apolipoprotein E genotype, the relative hazard associated with higher levels of acculturation was 1.83 (95% CI 0.4-8.5). Conclusion Japanese-Americans in the highest acculturation group appear to have an increased risk for acquiring AD, though the confidence interval includes the null value. This finding suggests further research to determine a biological rationale.