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1.
Glob Chang Biol ; 26(12): 7217-7228, 2020 Dec.
Article in English | MEDLINE | ID: mdl-32974963

ABSTRACT

Soil nutrient contents and organic carbon (C) stability are key indicators for restoration of degraded grassland. However, the effects of long-term active restoration of extremely degraded grassland on soil parameters have been equivocal. The aims of this study were to evaluate the impact of active restoration of degraded alpine grassland on: (a) soil organic matter (SOM) mineralization; and (b) the importance of biotic factors for temperature sensitivity (Q10 ) of SOM mineralization. Soils were sampled from intact, degraded and restored alpine grasslands at altitudes ranging between 3,900 and 4,200 m on the Tibetan Plateau. The samples were incubated at 5, 15 and 25°C, and Q10 values of SOM mineralization were determined. Structural equation modeling was used to evaluate the importance of vegetation, soil physico-chemical properties and microbial parameters for Q10 regulation. The Q10 of N mineralization was similar among intact, degraded and restored soils (0.84-1.24) and was higher in topsoil (1.09) than in subsoil (0.92). The best predictive factor of CO2 -Q10 for intact grassland was microbial biomass, for degraded grassland was basal microbial respiration, and for restored grassland was soil bulk density. Restoration by planting vegetation decreased the Q10 of SOM mineralization as soil bulk density, the most important negative predictor, increased in restored grassland. The Q10 of SOM mineralization in topsoil was 14% higher than in subsoil because of higher microbial abundance and exo-enzyme activities. The NH4 + content was greatest in intact soil, while NO3 - content was greatest in degraded soil. The SOM mineralization rate decreased with grassland degradation and increased after long-term (>10 years) restoration. In conclusion, extremely degraded grassland needs proper long-term management in active restoration projects, especially for improvement of soil nutrients in a harsh environment.


Subject(s)
Carbon , Soil , Biomass , Grassland , Soil Microbiology
2.
Cochrane Database Syst Rev ; 10: CD004427, 2017 10 06.
Article in English | MEDLINE | ID: mdl-28982219

ABSTRACT

BACKGROUND: Amyotrophic lateral sclerosis (ALS), also known as motor neuron disease, is a fatal neurodegenerative disease. Neuromuscular respiratory failure is the most common cause of death, which usually occurs within two to five years of the disease onset. Supporting respiratory function with mechanical ventilation may improve survival and quality of life. This is the second update of a review first published in 2009. OBJECTIVES: To assess the effects of mechanical ventilation (tracheostomy-assisted ventilation and non-invasive ventilation (NIV)) on survival, functional measures of disease progression, and quality of life in ALS, and to evaluate adverse events related to the intervention. SEARCH METHODS: We searched the Cochrane Neuromuscular Specialised Register, the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, Embase, CINAHL Plus, and AMED on 30 January 2017. We also searched two clinical trials registries for ongoing studies. SELECTION CRITERIA: Randomised controlled trials (RCTs) and quasi-RCTs involving non-invasive or tracheostomy-assisted ventilation in participants with a clinical diagnosis of ALS, independent of the reported outcomes. We included comparisons with no intervention or the best standard care. DATA COLLECTION AND ANALYSIS: For the original review, four review authors independently selected studies for assessment. Two review authors reviewed searches for this update. All review authors independently extracted data from the full text of selected studies and assessed the risk of bias in studies that met the inclusion criteria. We attempted to obtain missing data where possible. We planned to collect adverse event data from the included studies. MAIN RESULTS: For the original Cochrane Review, the review authors identified two RCTs involving 54 participants with ALS receiving NIV. There were no new RCTs or quasi-RCTs at the first update. One new RCT was identified in the second update but was excluded for the reasons outlined below.Incomplete data were available for one published study comparing early and late initiation of NIV (13 participants). We contacted the trial authors, who were not able to provide the missing data. The conclusions of the review were therefore based on a single study of 41 participants comparing NIV with standard care. Lack of (or uncertain) blinding represented a risk of bias for participant- and clinician-assessed outcomes such as quality of life, but it was otherwise a well-conducted study with a low risk of bias.The study provided moderate-quality evidence that overall median survival was significantly different between the group treated with NIV and the standard care group. The median survival in the NIV group was 48 days longer (219 days compared to 171 days for the standard care group (estimated 95% confidence interval 12 to 91 days, P = 0.0062)). This survival benefit was accompanied by an enhanced quality of life. On subgroup analysis, in the subgroup with normal to moderately impaired bulbar function (20 participants), median survival was 205 days longer (216 days in the NIV group versus 11 days in the standard care group, P = 0.0059), and quality of life measures were better than with standard care (low-quality evidence). In the participants with poor bulbar function (21 participants), NIV did not prolong survival or improve quality of life, although there was significant improvement in the mean symptoms domain of the Sleep Apnea Quality of Life Index by some measures. Neither trial reported clinical data on intervention-related adverse effects. AUTHORS' CONCLUSIONS: Moderate-quality evidence from a single RCT of NIV in 41 participants suggests that it significantly prolongs survival, and low-quality evidence indicates that it improves or maintains quality of life in people with ALS. Survival and quality of life were significantly improved in the subgroup of people with better bulbar function, but not in those with severe bulbar impairment. Adverse effects related to NIV should be systematically reported, as at present there is little information on this subject. More RCT evidence to support the use of NIV in ALS will be difficult to generate, as not offering NIV to the control group is no longer ethically justifiable. Future studies should examine the benefits of early intervention with NIV and establish the most appropriate timing for initiating NIV in order to obtain its maximum benefit. The effect of adding cough augmentation techniques to NIV also needs to be investigated in an RCT. Future studies should examine the health economics of NIV. Access to NIV remains restricted in many parts of the world, including Europe and North America. We need to understand the factors, personal and socioeconomic, that determine access to NIV.


Subject(s)
Amyotrophic Lateral Sclerosis/mortality , Quality of Life , Respiration, Artificial/mortality , Respiratory Insufficiency/mortality , Amyotrophic Lateral Sclerosis/complications , Disease Progression , Humans , Motor Neuron Disease/mortality , Randomized Controlled Trials as Topic , Respiration, Artificial/methods , Respiratory Insufficiency/etiology , Respiratory Insufficiency/therapy , Survival Analysis , Time Factors
3.
J Clin Neurosci ; 32: 51-6, 2016 Oct.
Article in English | MEDLINE | ID: mdl-27401224

ABSTRACT

Information regarding factors influencing prognosis and quality of life (QoL) in patients with amyotrophic lateral sclerosis (ALS) is useful for clinicians and also for patients and their carers. The aims of this study are to identify prognostic factors for survival in ALS and to determine the physical factors influencing QoL. This study is a retrospective analysis of a cohort of 512 patients who participated in a phase II/III clinical trial of olesoxime. Cox multivariate regression analysis found older age, bulbar onset disease, low baseline forced vital capacity, low baseline manual muscle test (MMT) scores and a shorter diagnostic delay to be independently associated with poor survival outcome. Physical factors shown to have the strongest correlation with poor QoL were low weight and a reduced ability to climb stairs. Therapeutic interventions including gastrostomy and non-invasive ventilation had no positive impact on QoL in this cohort. The prognostic factors for survival identified here are consistent with other studies of ALS patients, with the additional identification of baseline MMT score as another predictor of prognosis. Furthermore, the correlation between both weight and poor lower limb function with QoL is novel and underlines the importance of careful nutritional management in this hypercatabolic condition.


Subject(s)
Amyotrophic Lateral Sclerosis/diagnosis , Adult , Aged , Clinical Trials as Topic , Female , Humans , Male , Middle Aged , Multicenter Studies as Topic , Prognosis , Survival Analysis
5.
Article in English | MEDLINE | ID: mdl-26140500

ABSTRACT

A major problem faced by patients with amyotrophic lateral sclerosis (ALS) in respiratory failure is the inability to cough effectively. Forty eligible ALS patients were randomized to the breath-stacking technique using a lung volume recruitment bag (n = 21) or mechanical insufflator-exsufflator MI-E (n = 19) and followed up at three-monthly intervals for at least 12 months or until death. Results showed that there were 13 episodes of chest infection in the breath-stacking group and 19 episodes in the MI-E group (p = 0.92), requiring 90 and 95 days of antibiotics, respectively (p = 0.34). The mean duration of symptoms per chest infection was 6.9 days in the breath-stacking group and 3.9 days in MI-E group (p = 0.16). There were six episodes of hospitalization in each group (p = 0.64). The chance of hospitalization, in the event of a chest infection, was 0.46 in the breath-stacking group and 0.31 in MI-E group (p = 0.47). Median survival in the breath-stacking group was 535 days and 266 days in the MI-E group (p = 0.34). The QoL was maintained above 75% of baseline for a median of 329 days in the breath-stacking group and 205 days in the MI-E group (p = 0.41). In conclusion, lack of statistically significant differences due to sub-optimal power and confounders precludes a definitive conclusion with respect to the relative efficacy of one cough augmentation technique over the other. This study however, provides useful lessons and informative data, needed to strengthen the power calculation, inclusion criteria and randomization factors for a large scale definitive trial. Until such a definitive trial can be undertaken, we recommend the breath-stacking technique as a low-cost, first-line intervention for volume recruitment and cough augmentation in patients with ALS who meet the criteria for intervention with non-invasive ventilation.


Subject(s)
Amyotrophic Lateral Sclerosis/therapy , Cough , Respiratory Insufficiency/therapy , Respiratory Therapy/methods , Suction/methods , Aged , Amyotrophic Lateral Sclerosis/complications , Amyotrophic Lateral Sclerosis/mortality , Amyotrophic Lateral Sclerosis/physiopathology , Female , Humans , Kaplan-Meier Estimate , Male , Middle Aged , Noninvasive Ventilation , Proportional Hazards Models , Respiratory Insufficiency/etiology , Respiratory Insufficiency/mortality , Respiratory Insufficiency/physiopathology , Respiratory Therapy/instrumentation , Suction/instrumentation , Survival Rate , Treatment Outcome
6.
Article in English | MEDLINE | ID: mdl-26161993

ABSTRACT

Patients with ALS may have insufficientenergy substrates, due to dysphagia and hypermetabolism, which adversely affects the prognosis. Hyperlipidaemia has been reported to be associated with ALS and to represent a significant prognostic factor for survival in ALS. The aim of this study was to examine the prevalence of dyslipidaemia among a cohort of patients with ALS and how the lipid profile of patients with ALS influenced the prognosis. This was a prospective observational cohort study comprising 512 ALS patients, recruited for the TRO19622 (Olesoxime) investigational medicinal product trial. Fasting serum concentrations of total cholesterol (TC), low density lipoprotein cholesterol (LDL-C) and high density lipoprotein cholesterol (HDL-C) were measured as part of routine monitoring in the trial. Seventy-three percent of the participants had hypercholesterolaemia (defined as total cholesterol ≥ 5.1 mmol/l) at the screening visit. The prevalence of hypercholesterolaemia decreased with time and was 64% at 18 months follow-up. On unadjusted analysis total cholesterol, LDL-C and LDL/HDL ratio had a statistically significant effect on survival (p = 0.015, 0.003 and 0.027, respectively). When adjusted for prognostic covariates, however, none of the lipid measures was found to have a statistically significant effect on survival. In conclusion, prognosis in ALS is not influenced by the lipid profile of patients.


Subject(s)
Amyotrophic Lateral Sclerosis/epidemiology , Cholesterol, HDL/blood , Cholesterol, LDL/blood , Hypercholesterolemia/epidemiology , Adult , Aged , Amyotrophic Lateral Sclerosis/blood , Amyotrophic Lateral Sclerosis/drug therapy , Amyotrophic Lateral Sclerosis/mortality , Cholestenones/therapeutic use , Cholesterol/blood , Cohort Studies , Dyslipidemias/blood , Dyslipidemias/epidemiology , Female , Humans , Hypercholesterolemia/blood , Male , Middle Aged , Prevalence , Prognosis , Proportional Hazards Models , Prospective Studies
7.
Ecotoxicol Environ Saf ; 103: 101-7, 2014 May.
Article in English | MEDLINE | ID: mdl-24418797

ABSTRACT

Food chain contamination by cadmium (Cd) is globally a serious health concern resulting in chronic abnormalities. Rice is a major staple food of the majority world population, therefore, it is imperative to understand the relationship between the bioavailability of Cd in soils and its accumulation in rice grain. Objectives of this study were to establish environment quality standards for seven different textured soils based on human dietary toxicity, total Cd content in soils and bioavailable portion of Cd in soil. Cadmium concentrations in polished rice grain were best related to total Cd content in Mollisols and Udic Ferrisols with threshold levels of 0.77 and 0.32mgkg(-1), respectively. Contrastingly, Mehlich-3-extractable Cd thresholds were more suitable for Calcaric Regosols, Stagnic Anthrosols, Ustic Cambosols, Typic Haplustalfs and Periudic Argosols with thresholds values of 0.36, 0.22, 0.17, 0.08 and 0.03mgkg(-1), respectively. Stepwise multiple regression analysis indicated that phytoavailability of Cd to rice grain was strongly correlated with Mehlich-3-extractable Cd and soil pH. The empirical model developed in this study explains the combined effects of soil properties and extractable soil Cd content on the phytoavailability of Cd to polished rice grain. This study indicates that accumulation of Cd in rice is influenced greatly by soil type, which should be considered in assessment of soil safety for Cd contamination in rice. This investigation concluded that the selection of proper soil type for food crop production can help us to avoid the toxicity of Cd in our daily diet.


Subject(s)
Cadmium/analysis , Cadmium/pharmacokinetics , Food Safety , Oryza/chemistry , Oryza/metabolism , Soil/chemistry , Biological Availability , Biomass , Cadmium/toxicity , China , Guidelines as Topic , Humans , Oryza/drug effects , Oryza/growth & development , Soil Pollutants/analysis , Soil Pollutants/pharmacokinetics , Soil Pollutants/toxicity
10.
Cochrane Database Syst Rev ; (3): CD004427, 2013 Mar 28.
Article in English | MEDLINE | ID: mdl-23543531

ABSTRACT

BACKGROUND: Amyotrophic lateral sclerosis, also known as motor neuron disease, is a fatal neurodegenerative disease. Neuromuscular respiratory failure is the commonest cause of death, usually within two to five years of the disease onset. Supporting respiratory function with mechanical ventilation may improve survival and quality of life. This is the first update of a review first published in 2009. OBJECTIVES: The primary objective of the review is to examine the efficacy of mechanical ventilation (tracheostomy and non-invasive ventilation) in improving survival in ALS. The secondary objectives are to examine the effect of mechanical ventilation on functional measures of disease progression and quality of life in people with ALS; and assess adverse events related to the intervention. SEARCH METHODS: We searched The Cochrane Neuromuscular Disease Group Specialized Register (1 May 2012), CENTRAL (2012, Issue 4), MEDLINE (January 1966 to April 2012), EMBASE (January 1980 to April 2012), CINAHL Plus (January 1937 to April 2012), and AMED (January 1985 to April 2012). We also searched for ongoing studies on ClinicalTrials.gov. SELECTION CRITERIA: Randomised and quasi-randomised controlled trials involving non-invasive or tracheostomy assisted ventilation in participants with a clinical diagnosis of amyotrophic lateral sclerosis, independent of the reported outcomes. We planned to include comparisons with no intervention or the best standard care. DATA COLLECTION AND ANALYSIS: For the original review, four authors independently selected studies for assessment and two authors reviewed searches for this update. All authors extracted data independently from the full text of selected studies and assessed the risk of bias in studies that met the inclusion criteria. We attempted to obtain missing data where possible. We planned to collect adverse event data from included studies. MAIN RESULTS: For the original Cochrane review, the review authors identified and included two randomised controlled trials involving 54 participants with ALS receiving non-invasive ventilation. There were no new randomised or quasi-randomised controlled trials at this first update.Incomplete data were published for one study and we contacted the trial authors who were not able to provide the missing data. Therefore, the results of the review were based on a single study of 41 participants that compared non-invasive ventilation with standard care. It was a well conducted study with low risk of bias.The study showed that the overall median survival was significantly different between the group treated with non-invasive ventilation and the standard care group. The median survival in the non-invasive ventilation group was 48 days longer (219 days compared to 171 days for the standard care group (estimated 95% CI 12 to 91 days, P = 0.0062)). This survival benefit was accompanied by an enhanced quality of life. On subgroup analysis, the survival and quality of life benefit was much more in the subgroup with normal to moderately impaired bulbar function (20 participants); median survival was 205 days longer (216 days in NIV group versus 11 days in the standard care group, P = 0.0059). Non-invasive ventilation did not prolong survival in participants with poor bulbar function (21 participants), although it showed significant improvement in the mean symptoms domain of the Sleep Apnoea Quality of Life Index but not in the Short Form-36 Health Survey Mental Component Summary score. Neither trial reported clinical data on intervention related adverse effects. AUTHORS' CONCLUSIONS: Evidence from a single randomised trial of non-invasive ventilation in 41 participants suggests that it significantly prolongs survival and improves or maintains quality of life in people with ALS. Survival and some measures of quality of life were significantly improved in the subgroup of people with better bulbar function, but not in those with severe bulbar impairment. Future studies should examine the health economics of NIV and factors influencing access to NIV. We need to understand the factors, personal and socioeconomic, that determine access to NIV.


Subject(s)
Amyotrophic Lateral Sclerosis/mortality , Respiration, Artificial/mortality , Respiratory Insufficiency/mortality , Amyotrophic Lateral Sclerosis/complications , Disease Progression , Humans , Motor Neuron Disease/mortality , Quality of Life , Randomized Controlled Trials as Topic , Respiratory Insufficiency/etiology , Respiratory Insufficiency/therapy
11.
Amyotroph Lateral Scler ; 13(6): 528-32, 2012 Oct.
Article in English | MEDLINE | ID: mdl-22871078

ABSTRACT

Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative condition, respiratory failure being the commonest cause of death. Quality of life and survival can be improved by supporting respiratory function with non-invasive ventilation. Transcutaneous carbon dioxide monitoring is a non-invasive method of measuring arterial carbon dioxide levels enabling simple and efficient screening for respiratory failure. The aim of this study was to validate the accuracy of carbon dioxide level recorded transcutaneously with a TOSCA 500 monitor. It is a prospective, observational study of 40 consecutive patients with ALS, recruited from a specialist ALS clinic. The partial pressure of carbon dioxide (PCO(2)) in each patient was determined by both transcutaneous monitoring and by an arterialized ear lobe capillary blood sample. The carbon dioxide (CO(2)) levels obtained with these two methods were compared by Bland-Altman analysis. The results showed that the mean difference between arterialized and transcutaneous readings was - 0.083 kPa (SD 0.318). The Bland-Altman limits of agreement ranged from 0.553 to - 0.719 kPa. The difference was < 0.5 kPa in 90% of the recordings. Four of the 40 measurements had a difference of > 0.5 kPa, with a maximum recorded difference of 0.95 kPa. In conclusion, non-invasive carbon dioxide monitoring using a TOSCA monitor is a useful clinical tool in neurology practice. Users should be aware of the possibility of occasional inaccurate readings. A clinically unexpected or incompatible reading should be verified with a blood gas analysis, especially when a decision to provide ventilatory support is required.


Subject(s)
Amyotrophic Lateral Sclerosis/complications , Blood Gas Monitoring, Transcutaneous/methods , Carbon Dioxide , Respiratory Insufficiency/diagnosis , Respiratory Insufficiency/etiology , Adult , Aged , Aged, 80 and over , Blood Gas Monitoring, Transcutaneous/instrumentation , Carbon Dioxide/blood , Cohort Studies , Female , Humans , Male , Middle Aged , Observation , Partial Pressure
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