Some Swazi phytomedicines and their constituents

Ethnobotanical surveys of Manzini and Shiselweni regions of Swaziland were conducted to document new phytomedicines used in Swaziland and to determine their chemical constituents with a view toprovide the scientific basis of the use of the remedies in traditional medical practice and as a guide to bioprospecting for drugs. The plants collected in the surveys were extracted with suitable solvents andanalysed for secondary metabolites. Sixty one medicinal plants from thirty five families used for treating thirty one diseases were analysed. The medicinal uses of these plants had never been documentedin the pharmacopoeia of Swaziland. Different classes of secondary metabolites were found in the plants, namely alkaloids, anthranoids, flavonoids, glycosides, polyphenols, saponins, steroids andtannins. Some of the diseases the plants were used to treat are back ache, cardiac problems, chest pain, cough, diabetes, diarrhoea, headache, menorrhagia, snake bite, stomach ache and urino-genitalproblems. The presence of these secondary metabolites in the plants was of great importance in the understanding of the basis of the use of the plants in traditional medical practice and may provide alead in bioprospecting for new pharmaceutical products of herbal origin

Is intraindividual reaction time variability an independent cognitive predictor of mortality in old age? Findings from the Sydney Memory and Ageing Study

Intraindividual variability of reaction time (IIVRT), a proposed cognitive marker of neurobiological disturbance, increases in old age, and has been associated with dementia and mortality. The extent to which IIVRT is an independent predictor of mortality, however, is unclear. This study investigated the association of IIVRT and all-cause mortality while accounting for cognitive level, incident dementia and biomedical risk factors in 861 participants aged 70–90 from the Sydney Memory and Ageing Study. Participants completed two computerised reaction time (RT) tasks (76 trials in total) at baseline, and comprehensive medical and neuropsychological assessments every 2 years. Composite RT measures were derived from the two tasks—the mean RT and the IIVRT measure computed from the intraindividual standard deviation of the RTs (with age and time-on-task effects partialled out). Consensus dementia diagnoses were made by an expert panel of clinicians using clinical criteria, and mortality data were obtained from a state registry. Cox proportional hazards models estimated the association of IIVRT and mean RT with survival time over 8 years during which 191 (22.2%) participants died. Greater IIVRT but not mean RT significantly predicted survival time after adjusting for age, sex, global cognition score, cardiovascular risk index and apolipoprotein ɛ4 status. After excluding incident dementia cases, the association of IIVRT with mortality changed very little. Our findings suggest that greater IIVRT uniquely predicts shorter time to death and that lower global cognition and prodromal dementia in older individuals do not explain this relationship

Reaction Time Measures Predict Incident Dementia in Community-Living Older Adults: The Sydney Memory and Ageing Study

Objective To examine the utility of intraindividual variability of reaction times (IIVRT) and mean reaction time (RT) as behavioral markers of incident all-cause dementia. Methods A longitudinal cohort study followed biennially for 4 years, the community-based Sydney Memory and Ageing Study, 861 initially nondemented participants aged 70–90. Incident all-cause dementia determined by consensus, RT measures from simple and complex tasks, Mini-Mental State Exam and neuropsychological tests, Geriatric Depression Scale and Goldberg Anxiety Scale, cardiovascular risk score, apolipoprotein ε4 status, and the Bayer ADL Scale were used. Associations of baseline IIVRT and mean RT with time to dementia were evaluated with hazard ratios (HRs) using Cox proportional-hazards models with and without controlling for dementia risk factors. Results Forty-eight cases developed dementia. Greater complex IIVRT predicted a 40% (HR: 1.43) and mean RT a 50%–60% (simple RT: HR 1.53; complex RT: HR 1.59) per standard deviation increased risk of developing dementia, remaining significant after controlling for age, education, sex, general cognitive function, mood, cerebrovascular disease, and genetic susceptibility. Prediction of incident dementia using demographical information and RT measures combined was comparable with several traditional neuropsychological measures (AUC 0.75), although lower than a full neuropsychological battery (AUC 0.90). Prediction of functional decline by RT measures combined was equal to the neuropsychological battery (multiple Rs of .233 and .238, respectively). Conclusion Brief RT measures provided information on risk of imminent dementia and functional decline within 4 years in older adults at a population level, with mean RT the stronger predictor

The nature of functional variability in plantar pressure during a range of controlled walking speeds

During walking, variability in step parameters allows the body to adapt to changes in substrate or unexpected perturbations that may occur as the feet interface with the environment. Despite a rich literature describing biomechanical variability in step parameters, there are as yet no studies that consider variability at the body–environment interface. Here, we used pedobarographic statistical parametric mapping (pSPM) and two standard measures of variability, mean square error (m.s.e.) and the coefficient of variation (CV), to assess the magnitude and spatial variability in plantar pressure across a range of controlled walking speeds. Results by reduced major axis, and pSPM regression, revealed no consistent linear relationship between m.s.e. and speed or m.s.e. and Froude number. A positive linear relationship, however, was found between CV and walking speed and CV and Froude number. The spatial distribution of variability was highly disparate when assessed by m.s.e. and CV: relatively high variability was consistently confined to the medial and lateral forefoot when measured by m.s.e., while the forefoot and heel show high variability when measured by CV. In absolute terms, variability by CV was universally low (less than 2.5%). From these results, we determined that variability as assessed by m.s.e. is independent of speed, but dependent on speed when assessed by CV

Intraindividual Stepping Reaction Time Variability Predicts Falls in Older Adults With Mild Cognitive Impairment

Background: Reaction time measures have considerable potential to aid neuropsychological assessment in a variety of health care settings. One such measure, the intraindividual reaction time variability (IIV), is of particular interest as it is thought to reflect neurobiological disturbance. IIV is associated with a variety of age-related neurological disorders, as well as gait impairment and future falls in older adults. However, although persons diagnosed with Mild Cognitive Impairment (MCI) are at high risk of falling, the association between IIV and prospective falls is unknown. Methods: We conducted a longitudinal cohort study in cognitively intact (n = 271) and MCI (n = 154) community-dwelling adults aged 70–90 years. IIV was assessed through a variety of measures including simple and choice hand reaction time and choice stepping reaction time tasks (CSRT), the latter administered as a single task and also with a secondary working memory task. Results: Logistic regression did not show an association between IIV on the hand-held tasks and falls. Greater IIV in both CSRT tasks, however, did significantly increase the risk of future falls. This effect was specific to the MCI group, with a stronger effect in persons exhibiting gait, posture, or physiological impairment. Conclusions: The findings suggest that increased stepping IIV may indicate compromised neural circuitry involved in executive function, gait, and posture in persons with MCI increasing their risk of falling. IIV measures have potential to assess neurobiological disturbance underlying physical and cognitive dysfunction in old age, and aid fall risk assessment and routine care in community and health care settings

Risk factors for falls in community-dwelling older people with mild cognitive impairment: a prospective one-year study

Objective: Mild cognitive impairment (MCI) is considered an intermediate stage between normal cognitive function and dementia. Fall risk is increased in this group, but there is limited literature exploring specific fall risk factors that may be addressed in fall prevention strategies. The aim of this study was to examine risk factors for falls in older people with MCI, focusing on cognitive, psychological and physical factors. Methods: Participants (n = 266, 45% women) were community-dwelling older people aged 70–90 years who met the criteria for MCI. Cognitive, psychological, sensorimotor and physical assessments, physical activity levels, medication use, general health and disability were ascertained at baseline. Falls were monitored prospectively for 12 months. Results: During follow-up, 106 (40%) participants reported one or more falls. Poorer visual contrast sensitivity, increased postural sway, lower levels of weekly walking activity, higher levels of depressive symptoms and psychotropic medication use were significantly associated with faller status (≥1 falls) in univariable analyses. Of these factors, poor visual contrast sensitivity, increased postural sway and psychotropic medication use were found to be significant independent predictors of falls in multivariable analysis while controlling for age and sex. No measures of cognitive function were associated with falls. Conclusions: Poor visual contrast sensitivity, impaired balance and psychotropic medication use predicted falls in community-dwelling people with MCI. These risk factors may be amenable to intervention, so these factors could be carefully considered in fall prevention programs for this population

The Omega Deformation From String and M-Theory

We present a string theory construction of Omega-deformed four-dimensional gauge theories with generic values of \epsilon_1 and \epsilon_2. Our solution gives an explicit description of the geometry in the core of Nekrasov and Witten's realization of the instanton partition function, far from the asymptotic region of their background. This construction lifts naturally to M-theory and corresponds to an M5-brane wrapped on a Riemann surface with a selfdual flux. Via a 9-11 flip, we finally reinterpret the Omega deformation in terms of non-commutative geometry. Our solution generates all modified couplings of the \Omega-deformed gauge theory, and also yields a geometric origin for the quantum spectral curve of the associated quantum integrable system.Comment: LaTeX, 35 pages, 1 figure. Appendix on couplings of hypermultiplets in N=4 SYM adde

The Cytotoxic T Lymphocyte Antigen-4+49A/G Single Nucleotide Polymorphism Association With Visceral Leishmaniasis

Background: Several lines of evidence approve that innate and adaptive immunity play key roles in the defense against visceral leishmaniasis (VL). The polymorphism within the cytotoxic T lymphocyte antigen 4 (CTLA-4) gene alters its expression. Objectives: The main aim of this study was to evaluate the polymorphism within the +49 position of the CTLA-4 gene of Iranian patients with VL in comparison with healthy controls. Materials and Methods: In this cross-sectional study, 88 patients with clinical presentations of VL, who were seropositive for Leishmania (group 1), 86 patients without clinical presentations but seropositive (group 2), and 115 healthy controls (group 3) were assessed with respect to the CTLA-4 +49A/G polymorphism, using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). The anti-Leishmania antibody titration was evaluated using an immunofluorescence method. Results: Our results indicated that both CTLA-4 +49A/G polymorphisms were significantly associated with VL. Conclusions: According to the results, the polymorphisms within the +49 position of CTLA-4 can be associated with VL and may be considered as risk factors for the disease

Characterising Australian memory clinics: current practice and service needs informing national service guidelines

Background: Memory clinics (MCs) play a key role in accurate and timely diagnoses and treatment of dementia and mild cognitive impairment. However, within Australia, there are little data available on current practices in MCs, which hinder international comparisons for best practice, harmonisation efforts and national coordination. Here, we aimed to characterise current service profiles of Australian MCs. Methods: The ‘Australian Dementia Network Survey of Expert Opinion on Best Practice and the Current Clinical Landscape’ was conducted between August-September 2020 as part of a larger-scale Delphi process deployed to develop national MC guidelines. In this study, we report on the subset of questions pertaining to current practice including wait-times and post-diagnostic care. Results: Responses were received from 100 health professionals representing 60 separate clinics (45 public, 11 private, and 4 university/research clinics). The majority of participants were from clinics in metropolitan areas (79%) and in general were from high socioeconomic areas. While wait-times varied, only 28.3% of clinics were able to offer an appointment within 1-2 weeks for urgent referrals, with significantly more private clinics (58.3%) compared to public clinics (19.5%) being able to do so. Wait-times were less than 8 weeks for 34.5% of non-urgent referrals. Only 20.0 and 30.9% of clinics provided cognitive interventions or post-diagnostic support respectively, with 7.3% offering home-based reablement programs, and only 12.7% offering access to group-based education. Metropolitan clinics utilised neuropsychological assessments for a broader range of cases and were more likely to offer clinical trials and access to research opportunities. Conclusions: In comparison to similar countries with comprehensive government-funded public healthcare systems (i.e., United Kingdom, Ireland and Canada), wait-times for Australian MCs are long, and post-diagnostic support or evidence-based strategies targeting cognition are not common practice. The timely and important results of this study highlight a need for Australian MCs to adopt a more holistic service of multidisciplinary assessment and post-diagnostic support, as well as the need for the number of Australian MCs to be increased to match the rising number of dementia cases