The formate dehydrogenase (FDH) from Candida boidinii is a well-known enzyme in biocatalysis for NADH regeneration. Nevertheless, it has low activity in a water-miscible ionic liquid (1,3-dimethylimidazolium dimethyl phosphate, [MMIm][Me2 PO4 ]). In this work, this enzyme was subjected to directed evolution by using error-prone PCR, and a mutant (N187S/T321S) displaying higher activity was obtained following selection based on the formazan-based colorimetric assay. The mutation N187S is responsible for improved activity both in aqueous solution and in [MMIm][Me2 PO4 ], through an enhancement of the kcat value by a factor of 5.8. Fluorescence experiments performed in the presence of a quenching agent revealed that the mutant does not unfold in the presence of 50?% (v/v) [MMIm][Me2 PO4 ] whereas the wild-type enzyme does. Molecular modelling revealed that the mutation is located at the monomer-monomer interface and causes an increase in the pKa of residue E163 from 4.8 to 5.5. Calculation of the pKa of this residue in other microbial FDHs showed that thermostable FDHs have a highly basic glutamate at this position (pKa up to 6.2). We have identified a new site for improving FDH thermostability and tolerance to ionic liquids, and it is linked to the local charge of the enzymes in this class.
The epilepsy treatment gap is largest in resource-poor countries. We evaluated the efficacy of a 1-day health education program in a rural area of Kenya. The primary outcome was adherence to antiepileptic drugs (AEDs) as measured by drug levels in the blood, and the secondary outcomes were seizure frequency and Kilifi Epilepsy Beliefs and Attitudes Scores (KEBAS).
This study aims to improve recognition of hospice eligibility for patients with Parkinson disease (PD) by ascertaining which variables have a higher probability of occurring uniquely in 6 to 12 months before death when compared to 18 to 24 months before death. Participants were 339 patients who died who were diagnosed with PD or Parkinsonism and treated with dopaminergic prescriptions for at least 3 years in northwestern US Veterans Affairs medical centers. A range of indicators were compared across 3 time periods (30-36 months, 24-18 months, and 12-6 months before death) using within-subjects repeated measures design. Results indicate that body mass index less than 18, alone or combined with a shift in prescribing (when benefits of dopaminergic medications no longer outweigh their risk of side effects), may signal appropriate timing for hospice referral.
Family care research has identified negative outcomes of providing care to a spouse with Parkinsons disease (PD), such as declining physical and mental health. Research has also identified protective variables that decrease negative outcomes such as high mutuality and rewards of meaning. It is important for clinicians to identify "at risk" family caregivers and provide earlier interventions. Despite the importance of age and developmental stage there is a paucity of research comparing young versus older spouse caregivers. This study compared the difference in negative aspects of strain and modulators of strain in young and older PD spouse caregivers. A series of hierarchical multiple regressions were used to examine the contribution of age on both positive and negative aspects of the care situation for 65 (37 young, 28 old) PD spouse caregivers. Negative variables included 3 dimensions of strain; strain from lack of personal resources, strain from worry, and global strain. Positive or protective variables included mutuality, preparedness, and rewards of meaning. Even in early stage disease before significant care is required, young spouses (40-55) were found to be at greater risk for negative consequences of the care situation reporting significantly more strain from lack of personal resources, and lower levels of mutuality and rewards of meaning than older (greater than 70) spouses. As expected, young spouses were more likely to be working, caring for children in the home, and in better physical health than older spouses. Clinicians are well-situated to identify the unique needs of young spouses and intervene early in the caregiving trajectory. These findings provide ideas for targeted interventions. Future larger studies that compare young and older spouses should include later stage disease to more fully understand the developmental differences raised by the present findings.
Seizures are common in children admitted with severe falciparum malaria and are associated with neuro-cognitive impairments. Prolonged febrile seizures are associated with hippocampal damage and impaired memory. It was hypothesized that severe malaria causes impaired everyday memory which may be associated with hippocampal damage.
The objective of this study is to develop a culturally relevant community-based intervention for children with communication disabilities in Kenya through a community/researcher partnership. The resulting intervention is for use in a randomized control trial which will be reported at a later stage.
There is wide variability in how spouses providing care respond to their care situations. Few studies focus on the roles of both intra- and interpersonal factors in long-term spousal care, particularly in the context of Parkinsons disease (PD). The current study uses longitudinal data over a 10-year period to examine the roles of optimism, pessimism, mutuality, and spouse gender in predicting role strain in PD spouses.
Many people with epilepsy (PWE) in resource-poor countries do not receive appropriate treatment, a phenomenon referred to as the epilepsy treatment gap (ETG). We conducted a qualitative study to explore the reasons for this gap and to identify possible interventions in Kilifi, Kenya. Focus group discussions (FGDs) were carried out of PWE and their caregivers. Individual interviews were conducted of PWE, their caregivers, traditional healers, community health workers and leaders, nurses and doctors. In addition, a series of workshops was conducted, and four factors contributing to the ETG were identified: 1) lack of knowledge about the causes, treatment and prognosis of epilepsy; 2) inaccessibility to antiepileptic drugs; 3) misconceptions about epilepsy derived from superstitions about its origin; 4) and dissatisfaction with the communication skills of health providers. These data indicated possible interventions: 1) education and support for PWE and their caregivers; 2) communication skills training for health providers; 3) and improved drug provision.
Epilepsy remains misunderstood, particularly in resource poor countries (RPC). We developed and validated a tool to assess beliefs and attitudes about epilepsy among people with epilepsy (PWE) in Kilifi, Kenya. The 50-item scale was developed through a literature review and qualitative study findings, and its reliability and validity were assessed with 673 PWE. A final scale of 34 items had Cronbachs alpha scores for the five subscales: causes of epilepsy (?=0.71); biomedical treatment of epilepsy (?=0.70); cultural treatment of epilepsy (?=0.75); risk and safety concerns about epilepsy (?=0.56); and negative attitudes about epilepsy (?=0.76) and entire scale (?=0.70). Test-retest reliability was acceptable for all the subscales. The Kilifi Epilepsy Beliefs and Attitude Scale is a reliable and valid tool that measures beliefs and attitudes about epilepsy. It may be useful in other RPC or as a tool to assess the effectiveness of interventions to improve knowledge, beliefs, and attitudes about epilepsy.
Many people with epilepsy in low-income countries do not receive appropriate biomedical treatment. This epilepsy treatment gap might be caused by patients not seeking biomedical treatment or not adhering to prescribed antiepileptic drugs (AEDs). We measured the prevalence of and investigated risk factors for the epilepsy treatment gap in rural Kenya.
The aim of this study was to develop and validate a tool to measure perceived stigma among people with epilepsy (PWE) in Kilifi, Kenya. We reviewed existing scales that measured stigma, particularly of epilepsy. We conducted a qualitative study to determine salient concerns related to stigma in Kilifi. Themes were generated, and those related to stigma were used to construct an 18-item stigma scale. A descriptive cross-sectional survey was then conducted among 673 PWE to assess the reliability and validity of the scale. Internal consistency was calculated using Cronbachs alpha and test-retest reliability with an interclass correlation coefficient. The final scale had 15 items, which had high internal consistency (Cronbachs ?=0.91) and excellent test-retest reliability (r=0.92). Factor analysis indicated that the scale was unidimensional with one factor solution explaining 45.8% of the variance. The Kilifi Stigma Scale for Epilepsy is a culturally appropriate measure of stigma with strong psychometric properties.
This study sought to adapt a battery of Western speech and language assessment tools to a rural Kenyan setting. The tool was developed for children whose first language was KiGiryama, a Bantu language. A total of 539 Kenyan children (males=271, females=268, ethnicity=100% Kigiryama. Data were collected from 303 children admitted to hospital with severe malaria and 206 age-matched children recruited from the village communities. The language assessments were based upon the Content, Form and Use (C/F/U) model. The assessment was based upon the adapted versions of the Peabody Picture Vocabulary Test, Test for the Reception of Grammar, Renfrew Action Picture Test, Pragmatics Profile of Everyday Communication Skills in Children, Test of Word Finding and language specific tests of lexical semantics, higher level language. Preliminary measures of construct validity suggested that the theoretical assumptions behind the construction of the assessments were appropriate and re-test and inter-rater reliability scores were acceptable. These findings illustrate the potential to adapt Western speech and language assessments in other languages and settings, particularly those in which there is a paucity of standardised tools.
IMPORTANCE Convergent biological, epidemiological, and clinical data identified urate elevation as a candidate strategy for slowing disability progression in Parkinson disease (PD). OBJECTIVE To determine the safety, tolerability, and urate-elevating capability of the urate precursor inosine in early PD and to assess its suitability and potential design features for a disease-modification trial. DESIGN, SETTING, AND PARTICIPANTS The Safety of Urate Elevation in PD (SURE-PD) study, a randomized, double-blind, placebo-controlled, dose-ranging trial of inosine, enrolled participants from 2009 to 2011 and followed them for up to 25 months at outpatient visits to 17 credentialed clinical study sites of the Parkinson Study Group across the United States. Seventy-five consenting adults (mean age, 62 years; 55% women) with early PD not yet requiring symptomatic treatment and a serum urate concentration less than 6 mg/dL (the approximate population median) were enrolled. INTERVENTIONS Participants were randomized to 1 of 3 treatment arms: placebo or inosine titrated to produce mild (6.1-7.0 mg/dL) or moderate (7.1-8.0 mg/dL) serum urate elevation using 500-mg capsules taken orally up to 2 capsules 3 times per day. They were followed for up to 24 months (median, 18 months) while receiving the study drug plus 1 washout month. MAIN OUTCOMES AND MEASURES The prespecified primary outcomes were absence of unacceptable serious adverse events (safety), continued treatment without adverse event requiring dose reduction (tolerability), and elevation of urate assessed serially in serum and once (at 3 months) in cerebrospinal fluid. RESULTS Serious adverse events (17), including infrequent cardiovascular events, occurred at the same or lower rates in the inosine groups relative to placebo. No participant developed gout and 3 receiving inosine developed symptomatic urolithiasis. Treatment was tolerated by 95% of participants at 6 months, and no participant withdrew because of an adverse event. Serum urate rose by 2.3 and 3.0 mg/dL in the 2 inosine groups (P?<?.001 for each) vs placebo, and cerebrospinal fluid urate level was greater in both inosine groups (P?=?.006 and <.001, respectively). Secondary analyses demonstrated nonfutility of inosine treatment for slowing disability. CONCLUSIONS AND RELEVANCE Inosine was generally safe, tolerable, and effective in raising serum and cerebrospinal fluid urate levels in early PD. The findings support advancing to more definitive development of inosine as a potential disease-modifying therapy for PD. TRIAL REGISTRATION clinicaltrials.gov Identifier: NCT00833690.
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