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1.
Conserv Biol ; 30(5): 962-71, 2016 10.
Article in English | MEDLINE | ID: mdl-27341652

ABSTRACT

Southeast Asia possesses the highest rates of tropical deforestation globally and exceptional levels of species richness and endemism. Many countries in the region are also recognized for their food insecurity and poverty, making the reconciliation of agricultural production and forest conservation a particular priority. This reconciliation requires recognition of the trade-offs between competing land-use values and the subsequent incorporation of this information into policy making. To date, such reconciliation has been relatively unsuccessful across much of Southeast Asia. We propose an ecosystem services (ES) value-internalization framework that identifies the key challenges to such reconciliation. These challenges include lack of accessible ES valuation techniques; limited knowledge of the links between forests, food security, and human well-being; weak demand and political will for the integration of ES in economic activities and environmental regulation; a disconnect between decision makers and ES valuation; and lack of transparent discussion platforms where stakeholders can work toward consensus on negotiated land-use management decisions. Key research priorities to overcome these challenges are developing easy-to-use ES valuation techniques; quantifying links between forests and well-being that go beyond economic values; understanding factors that prevent the incorporation of ES into markets, regulations, and environmental certification schemes; understanding how to integrate ES valuation into policy making processes, and determining how to reduce corruption and power plays in land-use planning processes.


Subject(s)
Agriculture , Conservation of Natural Resources , Ecosystem , Forests , Asia, Southeastern , Humans
2.
J Ethnopharmacol ; 178: 323-33, 2016 Feb 03.
Article in English | MEDLINE | ID: mdl-26631758

ABSTRACT

ETHNOPHARMACOLOGICAL RELEVANCE: After almost 50 years of international trade in wild harvested medicinal bark from Africa and Madagascar, the example of Prunus africana holds several lessons for both policy and practice in the fields of forestry, conservation and rural development. Due to recent CITES restrictions on P. africana exports from Burundi, Kenya and Madagascar, coupled with the lifting of the 2007 European Union (EU) ban in 2011, Cameroon's share of the global P. africana bark trade has risen from an average of 38% between 1995 and 2004, to 72.6% (658.6 metric tons) in 2012. Cameroon is therefore at the center of this international policy arena. METHODS AND MATERIALS: This paper draws upon several approaches, combining knowledge in working with P. africana over a 30-year period with a thorough literature review and updated trade data with "ground-truthing" in the field in 2013 and 2014. This enabled the construction of a good perspective on trade volumes (1991-2012), bark prices (and value-chain data) and the gaps between research reports and practice. Two approaches provided excellent lenses for a deeper understanding of policy failure and the "knowing-doing gap" in the P. africana case. A similar approach to Médard's (1992) analyses of power, politics and African development was taken and secondly, studies of commodity chains that assess the power relations that coalesce around different commodities (Ribot, 1998; Ribot and Peluso, 2003). RESULTS: Despite the need to conserve genetically and chemically diverse P. africana, wild populations are vulnerable, even in several "protected areas" in Burundi, Cameroon, the Democratic Republic of Congo and in the forest reserves of Madagascar. Secondly, hopes of decentralized governance of this forest product are misplaced due to elite capture, market monopolies and subsidized management regimes. At the current European price, for P. africana bark (US$6 per kg) for example, the 2012 bark quota (658.675t) from Cameroon alone was worth over US$3.9 million, with the majority of this accruing to a single company. In contrast to lucrative bark exports, the livelihood benefits and financial returns to local harvesters from wild harvest are extremely low. For example, in 2012, the 48 active harvesters working within Mount Cameroon National Park (MCNP) received less than 1US$ per day from bark harvests, due to a net bark price of 0.33 US$ per kg (or 43% of the farm gate price for wild harvested bark). In addition, the costs of inventory, monitoring and managing sustainable wild harvests are far greater than the benefits to harvesters. CONCLUSION: Without the current substantial international donor subsidies, sustainable harvest cannot be sustained. What is required to supply the current and future market is to develop separate, traceable P. africana bark supply chains based on cultivated stocks. On-farm production would benefit thousands of small-scale farmers cultivating P. africana, including local women, for whom wild harvesting is too onerous. This change requires CITES and EU support and would catalyze P. africana cultivation in across several montane African countries and Madagascar, increasing farm-gate prices to harvesters compared to economic returns from wild harvest.


Subject(s)
Commerce/economics , Commerce/legislation & jurisprudence , Plant Bark/growth & development , Plant Extracts/economics , Plants, Medicinal/growth & development , Prunus africana/growth & development , Africa , Cameroon , Conservation of Natural Resources/economics , Humans , Madagascar , Plant Extracts/therapeutic use
7.
Neuropsychologia ; 40(13): 2226-33, 2002.
Article in English | MEDLINE | ID: mdl-12417453

ABSTRACT

Two robust findings in the Alzheimer's literature are that patients with Alzheimer's disease (AD) show executive function and primacy deficits. The present study examined whether we would find similar deficits when comparing two groups of middle-aged individuals who differed with respect to genetic risk for AD, based on their apolipoprotein E (APOE) genotype. All individuals were screened as normal on a battery of standardized cognitive measures. They were tested on the "Operation span task", which engages the central executive component of working memory [J. Exp. Psychol.: Gen. 128 (1999) 309, J. Exp. Psychol.: Gen. 126 (1997) 211, J. Mem. Language 39 (1998) 418] by dividing attention between processing math operations and remembering words. Individuals were grouped according to APOE genotype ( epsilon 4 carrier versus epsilon 4 non-carrier), matched on age and education, and their Total span and Primacy scores were compared. Despite having no overt symptoms of dementia or deficits on a series of standardized psychometric tests, the epsilon 4 carriers showed divided-attention and primacy deficits on the Operation span task, when compared to the epsilon 4 non-carriers. As a point of comparison, Primacy scores were extracted from the first trial of the "Buschke selective reminding task" [J. Verbal Learn. Verbal Behav. 12 (1973) 543] for these same individuals, and no group differences were found. The Buschke task is a list-learning task that does not require divided attention. These findings suggested that the epsilon 4 carriers were less able to divide their attention, when compared to the epsilon 4 non-carriers. The findings provide the first direct evidence for a relationship between APOE genotype and cognitive performance on measures of divided attention and primacy with non-demented individuals who showed no cognitive impairments on standardized measures.


Subject(s)
Alzheimer Disease/complications , Alzheimer Disease/metabolism , Apolipoproteins E/metabolism , Memory Disorders/etiology , Aged , Cues , Female , Follow-Up Studies , Humans , Male , Memory Disorders/diagnosis , Middle Aged , Neuropsychological Tests
8.
Acta Psychiatr Scand ; 105(3): 231-4, 2002 Mar.
Article in English | MEDLINE | ID: mdl-11939978

ABSTRACT

OBJECTIVE: To determine if elderly bereaved depressed subjects display difficulty with activities of daily living (ADL) and if their ADL difficulty improves with psychopharmacologic intervention. METHOD: The Assessment of Motor and Process Skills (AMPS), an ADL assessment measuring ADL motor and ADL process skills, was administered to a pilot sample of elderly persons with post-bereavement depression prior to psychopharmacologic intervention and subsequently during treatment response. RESULTS: In the pretreatment phase, subjects displayed difficulty with ADL motor and ADL process skills that significantly improved during the treatment response phase. CONCLUSION: Results suggest that elderly bereaved depressed individuals demonstrated ADL difficulty that responds positively to psychopharmacologic intervention.


Subject(s)
Activities of Daily Living/psychology , Depressive Disorder/psychology , Aged , Antidepressive Agents/therapeutic use , Bereavement , Depressive Disorder/drug therapy , Double-Blind Method , Female , Humans , Male , Middle Aged , Nortriptyline/therapeutic use , Pilot Projects , Psychiatric Status Rating Scales , Sertraline/therapeutic use , Treatment Outcome
9.
Neuropsychopharmacology ; 25(4): 555-64, 2001 Oct.
Article in English | MEDLINE | ID: mdl-11557169

ABSTRACT

Little is known about acetylcholine (ACh) modulation of central visual processing in humans. Receptor densities in visual brain regions are differentially distributed suggesting that receptor subtypes have different functions. Using PET, we have previously described the brain regions activated by a simple pattern-flash stimulus in healthy elderly subjects. To evaluate muscarinic and nicotinic contributions to ACh modulation of visual processing, we scanned elderly subjects watching the pattern-flash stimulus during no drug, during physostigmine augmentation, and during scopolamine antagonism of physostigmine's action. These manipulations of ACh significantly altered regional cerebral blood flow (rCBF) in brain regions activated by the task. The pattern of rCBF values across drug conditions suggested that muscarinic and nicotinic effects were dissociated. Muscarinic action predominated in striate cortex (Brodmann Area, BA 17) and lateral visual association areas (BA 18, 19), while nicotinic action predominated in the thalamus and inferior parietal regions (BA 39/40). Both muscarinic and nicotinic actions increased rCBF in some regions while decreasing it in others. A parsimonious reconciliation of these results with functional anatomy suggests that muscarinic action modulates visual attribute processing, while nicotinic action modulates arousal and selective attention to the visual task.


Subject(s)
Attention/drug effects , Receptors, Muscarinic/drug effects , Receptors, Nicotinic/drug effects , Visual Perception/drug effects , Aged , Brain Chemistry/drug effects , Cerebrovascular Circulation/drug effects , Cholinesterase Inhibitors/pharmacology , Double-Blind Method , Female , Humans , Male , Middle Aged , Muscarinic Antagonists/pharmacology , Neuropsychological Tests , Photic Stimulation , Physostigmine/adverse effects , Physostigmine/pharmacology , Scopolamine/adverse effects , Scopolamine/pharmacology , Tomography, Emission-Computed
10.
Neurobiol Aging ; 22(2): 237-46, 2001.
Article in English | MEDLINE | ID: mdl-11182473

ABSTRACT

Changes in regional cerebral blood flow (rCBF) in eleven elderly subjects during pairings of tone and air puff were compared to rCBF changes during pairings in young subjects. Although all subjects reported being aware of the relationship between tone and air puff, elderly subjects did not condition as well as young subjects and their rCBF measures were attenuated. Covarying the performance differences between young and old subjects did not change this conclusion suggesting that differences in neural activation during learning are related to binding of CS-US information prior to the impact of the association on performance. Both groups showed learning-specific rCBF changes in cerebellum, inferior right prefrontal cortex and posterior cingulate. However, only in young subjects were there learning-specific changes in rCBF in left temporal cortex, midbrain, caudate, and inferior left prefrontal cortex. Analysis of learning-dependent patterns of functional connectivity of inferior left prefrontal cortex showed only young subjects had a strong left prefrontal functional connectivity with cerebellum, hippocampus, thalamus and temporal cortex. Thus, beyond changes in regional activity, these data also suggest that age may alter the operations of functional networks underlying learning and memory.


Subject(s)
Aging/physiology , Conditioning, Eyelid/physiology , Prefrontal Cortex/physiology , Adolescent , Adult , Aged , Cerebellum/blood supply , Cerebellum/physiology , Cerebrovascular Circulation , Extinction, Psychological/physiology , Female , Humans , Middle Aged , Prefrontal Cortex/blood supply , Temporal Lobe/blood supply , Temporal Lobe/physiology , Tomography, Emission-Computed
11.
Neurology ; 57(12): 2223-8, 2001 Dec 26.
Article in English | MEDLINE | ID: mdl-11756601

ABSTRACT

OBJECTIVE: To determine whether the presence of a single epsilon4 allele of the APOE gene is associated with an increased rate of hippocampal volume loss or decline in cognition in healthy women in their sixth decade of life. METHODS: Nine APOE-epsilon4 allele-negative (mean age +/- SD, 60.6 +/- 10.2 years) and 16 APOE-epsilon4 allele-positive (mean age +/- SD, 55.1 +/- 6.0 years) healthy women underwent neurocognitive testing and MRI at the time of entry into the study (baseline) and 2 years later. Neurocognitive testing consisted of the Buschke-Fuld Free Recall, verbal fluency tests, the Rey Figure Test, the Wechsler Memory Scale-Revised, and the Wechsler Adult Intelligence Survey-Revised Block Design. Hippocampal volume determinations were based on manual outlining of sagittal slices aided by axial, coronal, and three-dimensional views of high-resolution 124-slice whole-brain scans; the scans were obtained with a 1.5-tesla scanner using a T1-weighted three-dimensional gradient echo sequence with RF spoiling (TR/TE/flip angle, 24 msec/3 msec/30 degrees ). RESULTS: The percent change in hippocampal volume per year was greater in the APOE-epsilon4 allele-positive group (mean +/- SD, 2.32 +/- 1.75%) than in the APOE-epsilon4 allele-negative group (mean +/- SD, 0.77 +/- 1.02%; t = 2.41; p < 0.03, two-tailed test). There were no significant differences between the two groups in terms of any of the cognitive measures, and hippocampal volume loss was not correlated with changes in any of the above-mentioned cognitive measures. CONCLUSIONS: The presence of a single APOE-epsilon4 allele is associated with an increased rate of hippocampal volume loss in healthy women in their sixth decade of life that is not related to any detectable memory changes.


Subject(s)
Aging , Apolipoproteins E/genetics , Hippocampus/anatomy & histology , Aged , Aging/psychology , Female , Genotype , Humans , Magnetic Resonance Imaging , Middle Aged , Neuropsychological Tests , Polymerase Chain Reaction
12.
Synapse ; 38(2): 226-9, 2000 Nov.
Article in English | MEDLINE | ID: mdl-11018796

ABSTRACT

Opiate receptor avidity (B(')(max)/K(D)), was measured in the subcortex of nine females (five healthy subjects, four Alzheimer patients) and 15 males (seven healthy subjects, eight Alzheimer patients), 51-75 years of age, with the opiate receptor antagonist 6-deoxy-6-beta-[(18)F]fluoronaltrexone (cyclofoxy, CF) and a positron emission tomograph. CF avidity was 27.5% less in the thalamus of healthy women compared to healthy men and 48.5% less in Alzheimer disease female patients compared to male patients.


Subject(s)
Alzheimer Disease/metabolism , Naltrexone/analogs & derivatives , Receptors, Opioid/metabolism , Thalamus/metabolism , Aged , Alzheimer Disease/diagnostic imaging , Analysis of Variance , Female , Humans , Male , Middle Aged , Naltrexone/metabolism , Regression Analysis , Sex Factors , Thalamus/diagnostic imaging , Tomography, Emission-Computed
13.
Proc Natl Acad Sci U S A ; 97(21): 11661-6, 2000 Oct 10.
Article in English | MEDLINE | ID: mdl-11027364

ABSTRACT

The epsilon4 allele of the apolipoprotein E (APOE) gene is associated with altered brain physiology in healthy adults before old age, but concomitant deficits in cognition on standardized tests of cognitive function have not been consistently demonstrated. We hypothesized that sensitive and specific assessment of basic attentional functions that underlie complex cognition would reveal evidence of impairment in otherwise asymptomatic individuals. We found that as early as middle age, nondemented carriers of the varepsilon4 allele of the APOE gene showed deficits when visual attention was spatially directed by cues in tasks of visual discrimination and visual search, in comparison to those without the epsilon4 allele (epsilon2 and epsilon3 carriers). Two component attentional operations were selectively affected: (i) shifting spatial attention following invalid location cues, and (ii) adjusting the spatial scale of attention during visual search. These changes occurred only in the presence of the epsilon4 allele and without decline in other aspects of attention (vigilance), memory, or general cognition. The results show that specific components of visual attention are affected by APOE genotype and that the course of cognitive aging is subject to selective alteration by a genetic trait.


Subject(s)
Apolipoproteins E/genetics , Attention , Genetic Carrier Screening , Visual Perception/genetics , Apolipoprotein E4 , Humans , Middle Aged
15.
Neuropsychology ; 14(2): 288-98, 2000 Apr.
Article in English | MEDLINE | ID: mdl-10791868

ABSTRACT

Location precues were used to manipulate the spatial scale of attention in visual search for a target in an array of letters in patients with dementia of the Alzheimer type (DAT) and in age-matched older controls. Cue size varied in the amount of spatial precision conferred. Scopolamine, a muscarinic antagonist, decreased overall arousal and broadened spatial attention after a precise precue (small and valid) to target location for DAT patients but not for controls, suggesting a selective effect for attentional impairment induced by cholinergic blockade. In contrast, physostigmine, a cholinesterase inhibitor, did not alter the distribution of spatial attention relative to no-drug baseline testing for patients. Results support a differential role for cholinergic mechanisms in the modulation of the spatial scale of visual attention.


Subject(s)
Acetylcholine/metabolism , Alzheimer Disease/metabolism , Alzheimer Disease/psychology , Attention/drug effects , Cholinergic Agents/pharmacology , Pattern Recognition, Visual/drug effects , Aged , Aged, 80 and over , Arousal/drug effects , Case-Control Studies , Cholinesterase Inhibitors/pharmacology , Cues , Female , Humans , Male , Middle Aged , Models, Neurological , Muscarinic Antagonists/pharmacology , Physostigmine/pharmacology , Scopolamine/pharmacology , Space Perception/drug effects
16.
Harv Rev Psychiatry ; 7(6): 311-33, 2000.
Article in English | MEDLINE | ID: mdl-10749389

ABSTRACT

Older adults respond less predictably than younger adults to most medications, typically requiring lower daily doses to achieve desired therapeutic effects and minimize adverse effects and toxicity. This unpredictability is particularly evident among the frail elderly, who are at the upper extreme of the life cycle and often suffer from central neurodegenerative disorders and/or a significant burden of comorbid medical problems. Yet this population has a burgeoning need for clinical services and in recent years has become an increasingly important focus of attention among practitioners. The goal of this review is to provide clinicians with a conceptual framework for understanding and responding to aging and age-related events that influence pharmacotherapeutics in older patients with behavioral disorders. Limitations and gaps in our knowledge base are also highlighted. The article includes a phenomenological overview of the aging process, a consideration of age-related factors that influence the pharmacokinetic and pharmacodynamic properties of psychotropic drugs, and suggested methods of enhancing medication compliance.


Subject(s)
Aging/metabolism , Frail Elderly , Mental Disorders/drug therapy , Psychotropic Drugs/pharmacokinetics , Psychotropic Drugs/therapeutic use , Aged , Aged, 80 and over , Brain/metabolism , Cytochrome P-450 Enzyme System/metabolism , Humans , Kidney/metabolism , Liver/metabolism , Mental Disorders/metabolism , Patient Compliance , Protein Binding , Psychotropic Drugs/adverse effects , Psychotropic Drugs/metabolism
17.
Clin Chim Acta ; 293(1-2): 213-21, 2000 Mar.
Article in English | MEDLINE | ID: mdl-10699435

ABSTRACT

Apolipoprotein E (APOE) genotyping usually involves polymerase chain reaction (PCR) and assessment of restriction fragment length polymorphism (RFLP) by gel electrophoresis. We made determination of HhaI restriction endonuclease digestive patterns more objective and improved diagnostic accuracy with a quantitative approach using sensitive DNA stain (SYBR Green) and image analysis of gel patterns. For distinguishing true and partially-digested restriction fragments, band ratios were calculated for the staining intensity of gel patterns from 116 sample runs of 63 human blood specimens. Each of these specimens was independently genotyped for APOE by at least two (and most of them by three) different PCR-RFLP methods. Based on the distribution of band ratios, decision levels were established and used for developing a program for computer-aided interpretation of APOE genotypes (Microsoft Excel software). Appropriateness of the decision levels for band ratios was validated by APOE genotyping of additional 61 specimens. The approach described here is applicable to a variety of other molecular diagnostic techniques that are based on PCR-RFLP or sequence-specific signal amplifications.


Subject(s)
Apolipoproteins E/genetics , False Positive Reactions , Genotype , Humans , Image Processing, Computer-Assisted , Polymerase Chain Reaction , Polymorphism, Restriction Fragment Length
18.
J Outcome Meas ; 3(4): 297-307, 1999.
Article in English | MEDLINE | ID: mdl-10572383

ABSTRACT

The Daily Activities Questionnaire (DAQ) was developed to assess activities of daily living (ADL) independence in people with Alzheimer's disease. After administering it to 276 people diagnosed with Alzheimer's disease, we examined the quality of the rating scale and its structure using a Rasch measurement approach. Results indicated that the original 10-point rating scale should be restructured to a 5-point rating scale to improve the quality of the instrument. In addition, we found that all but two ADL items defined the same construct and could be combined into a single summary measure of ADL independence. The remaining items were positioned along a hierarchical continuum, with IADL tasks more difficult than PADL tasks. Furthermore, the tasks were logically ordered by difficulty. We therefore report that the DAQ is a valid scale and conclude that it is a viable measure of ADL independence for studies of Alzheimer's disease.


Subject(s)
Activities of Daily Living , Alzheimer Disease/physiopathology , Psychometrics/methods , Surveys and Questionnaires , Aged , Aged, 80 and over , Data Interpretation, Statistical , Female , Humans , Male , Middle Aged
19.
Biol Psychiatry ; 46(6): 750-5, 1999 Sep 15.
Article in English | MEDLINE | ID: mdl-10494442

ABSTRACT

BACKGROUND: Antemortem levels of tau in the cerebrospinal fluid (CSF) of Alzheimer's disease (AD) patients have repeatedly been demonstrated to be elevated when compared to controls. Although CSF tau has been reported to be elevated even in very mild AD, it is unknown how tau levels change during the course of the disease. METHODS: We have followed 29 mild-to-moderately affected AD subjects over 2 years with repeated CSF taps. Clinical measures of dementia severity (Clinical Dementia Rating Scale, Global Deterioration Scale and Mini-Mental Status Examination) were obtained at the start and conclusion of the observation period, and CSF tau was measured with a standard enzyme-linked immunoabsorbent assay (ELISA) using two monoclonal antibodies. RESULTS: Despite significant changes in the clinical measures consistent with progression of the disease, no significant overall change in CSF tau levels (548 +/- 355 vs. 557 +/- 275 pg/mL, NS) was observed. None of the clinical variables was significantly correlated with either baseline measures of CSF tau or delta CSF tau (last-first). Similarly, CSF tau at baseline and changes over time were not significantly related to Apolipoprotein E (APO E) phenotype. CONCLUSIONS: These data suggest that CSF tau levels are stable over extended periods of time in a group of mild-to-moderately demented AD subjects and that CSF tau levels do not predict the severity or rate of progression of AD, at least not during the middle stages of the illness.


Subject(s)
Alzheimer Disease/cerebrospinal fluid , tau Proteins/cerebrospinal fluid , Aged , Alleles , Alzheimer Disease/diagnosis , Antibodies, Monoclonal , Apolipoproteins E/genetics , Enzyme-Linked Immunosorbent Assay , Female , Follow-Up Studies , Humans , Male , Phenotype , Reference Values , Severity of Illness Index , Time Factors
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