Non-communicable disease risk factors and management among internal migrant in China: systematic review and meta-analysis

Background

In 2019, there are more than 290 million people who have ever migrated from rural to urban areas in China. These rural-to-urban internal migrants account for more than one-fifth of China’s population and is the largest internal migrant group globally. We present the first systematic review that examines whether internal migrants are more likely to exhibit non-communicable diseases (NCDs) risk factors and have worse NCD management outcomes than non-migrant counterparts in China.

Methods

A systematic review was conducted via medical, public health, and economic databases including Scopus, MEDLINE, JSTOR, WHO Library Database and World Bank e-Library from 2000 to 2020. Study quality was assessed using the National Institute of Health Quality Assessment tool. We conducted a narrative review and synthesised differences for all studies included, stratified by different types of outcomes. We also conducted random-effects meta-analysis where we had a minimum of two studies with 95% CIs reported. The study protocol has been registered with PROSPERO: CRD42019139407.

Results

For most NCD risk factors and care cascade management, comparisons between internal migrants and other populations were either statistically insignificant or inconclusive. While most studies found migrants have a higher prevalence of tobacco use than urban residents, these differences were not statistically significant in the meta-analysis. Although three out four studies suggested that migrants may have worse access to NCD treatment and both studies suggested migrants have lower blood pressure control rates than non-migrants, these findings were not statistically significant.

Conclusion

Findings from this systematic review demonstrate that there is currently insufficient evidence on migrant and non-migrant differences in NCD risk factors and management in China. Further research is expected to investigate access to healthcare among internal and its effect on both their NCD outcomes and long-term healthcare costs in China.

Is there an association between public spending on health and choice of healthcare providers across socioeconomic groups in India? - Evidence from a national sample

The role of public spending on health in reducing socioeconomic inequalities in healthcare is an emerging area of research, little supporting empirical evidence is available from low- and middle-income countries. This study examined: (1) the relationship between public spending on health per capita and the decision whether to seek healthcare or not, (2) the relationships between public spending on health per capita and choice of medical provider, and (3) whether these relationships varied by socioeconomic groups in India. Our study utilized the nationally representative 71st National Sample Survey of India, using 26,142 people who had been ailing in the past 15 days, the survey took place between the 1st of January and June 30, 2014. Two regression-based approaches were used to examine the association between public spending and choice of medical providers: (1) Multilevel multinomial regression; and (2) Instrumental variable regression. We examined the differential impacts of public spending on healthcare utilisation by socioeconomic groups. Increased public spending on health was not associated with changes in ailing people's decision whether to seek care or not (p > 0.05 in all analyses). However, increased public spending on health was associated with reductions in patients choosing private medical providers [adjusted odds ratio = 0.88 (95%CI 0.85-0.91) for outpatient private clinics] compared to outpatient government clinics. These associations may be greater among the lower economic groups compared with their counterparts. Across India, higher levels of government investment in health services are recognised by healthcare users and shown in their pattern of healthcare utilisation. That an increase in public spending on health results in a decrease in the use of private providers, particularly outpatient facilities with no inpatient capabilities, provides strong evidence for the effectiveness of 'regulation by competition'. This is a strong argument for focusing health system strengthening, and strategies for achieving universal healthcare on public investment.

The Joint Effect of Physical Multimorbidity and Mental Health Conditions Among Adults in Australia

Introduction

The prevalence of chronic physical and mental health conditions is rising globally. Little evidence exists on the joint effect of physical and mental health conditions on health care use, work productivity, and health-related quality of life in Australia.

Methods

We analyzed data from the Household, Income and Labour Dynamics in Australia (HILDA) Survey, waves 9 (2009), 13 (2013), and 17 (2017). Economic effects associated with multimorbidity were measured through health service use, work productivity loss, and health-related quality of life. We used generalized estimating equations to assess the effect of the association between physical multimorbidity and mental health conditions and economic outcomes.

Results

From 2009 through 2017 the prevalence of physical multimorbidity increased from 15.1% to 16.2%, and the prevalence of mental health conditions increased from 11.2% to 17.3%. The number of physical health conditions was associated with the number of health services used (general practitioner visits, incidence rate ratio = 1.41), work productivity loss (labor force participation, adjusted odds ratio = 0.71), and reduced health-related quality of life (SF-6D score: Coefficient = −0.03). These effects were exacerbated by the presence of mental health conditions and low socioeconomic status.

Conclusion

Having multiple physical health conditions (physical multimorbidity) creates substantial health and financial burdens on individuals, the health system, and society, including increased use of health services, loss of work productivity, and decreased health-related quality of life. The adverse effects of multimorbidity on health, quality of life, and economic well-being are exacerbated by the co-occurrence of mental health conditions and low socioeconomic status.

Distinct Proteomic Signatures in 16 HDL (High-Density Lipoprotein) Subspecies

Objective- HDL (high-density lipoprotein) in plasma is a heterogeneous group of lipoproteins typically containing apo AI as the principal protein. Most HDLs contain additional proteins from a palate of nearly 100 HDL-associated polypeptides. We hypothesized that some of these proteins define distinct and stable apo AI HDL subspecies with unique proteomes that drive function and associations with disease. Approach and Results- We produced 17 plasma pools from 80 normolipidemic human participants (32 men, 48 women; aged 21-66 years). Using immunoaffinity isolation techniques, we isolated apo AI containing species from plasma and then used antibodies to 16 additional HDL protein components to isolate compositional subspecies. We characterized previously described HDL subspecies containing apo AII, apo CIII, and apo E; and 13 novel HDL subspecies defined by presence of apo AIV, apo CI, apo CII, apo J, α-1-antitrypsin, α-2-macroglobulin, plasminogen, fibrinogen, ceruloplasmin, haptoglobin, paraoxonase-1, apo LI, or complement C3. The novel species ranged in abundance from 1% to 18% of total plasma apo AI. Their concentrations were stable over time as demonstrated by intraclass correlations in repeated sampling from the same participants over 3 to 24 months (0.33-0.86; mean 0.62). Some proteomes of the subspecies relative to total HDL were strongly correlated, often among subspecies defined by similar functions: lipid metabolism, hemostasis, antioxidant, or anti-inflammatory. Permutation analysis showed that the proteomes of 12 of the 16 subspecies differed significantly from that of total HDL. Conclusions- Taken together, correlation and permutation analyses support speciation of HDL. Functional studies of these novel subspecies and determination of their relation to diseases may provide new avenues to understand the HDL system of lipoproteins.

Development and characterisation of a novel rat model of Parkinson's disease induced by sequential intranigral administration of AAV-α-synuclein and the pesticide, rotenone

Modeling Parkinson's disease remains a major challenge for preclinical researchers, as existing models fail to reliably recapitulate all of the classic features of the disease, namely, the progressive emergence of a bradykinetic motor syndrome with underlying nigrostriatal α-synuclein protein accumulation and nigrostriatal neurodegeneration. One limitation of the existing models is that they are normally induced by a single neuropathological insult, whereas the human disease is thought to be multifactorial with genetic and environmental factors contributing to the disease pathogenesis. Thus, in order to develop a more relevant model, we sought to determine if administration of the Parkinson's disease-associated pesticide, rotenone, into the substantia nigra of rats overexpressing the Parkinson's disease-associated protein, α-synuclein, could reliably model the triad of classic features of the human disease. To do so, rats underwent stereotaxic surgery for unilateral delivery of the adeno-associated virus (AAV)-α-synuclein into the substantia nigra. This was followed 13 weeks later by delivery of rotenone into the same site. The effect of the genetic and environmental insults alone or in combination on lateralised motor performance (Corridor, Stepping, and Whisker Tests), nigrostriatal integrity (tyrosine hydroxylase immunohistochemistry), and α-synucleinopathy (α-synuclein immunohistochemistry) was assessed. We found that rats treated with either AAV-α-synuclein or rotenone developed significant motor dysfunction with underlying nigrostriatal neurodegeneration. However, when the genetic and environmental insults were sequentially administered, the detrimental impact of the combined insults on motor performance and nigrostriatal integrity was significantly greater than the impact of either insult alone. This indicates that sequential exposure to relevant genetic and environmental insults is a valid approach to modeling human Parkinson's disease in the rat.

GP discussion of prognosis with patients with severe chronic obstructive pulmonary disease: a qualitative study

BACKGROUND

Recent research shows that health professionals do not communicate about prognosis with patients with chronic obstructive pulmonary disease (COPD) as openly as with patients who have cancer.

AIM

To identify strategies that general practitioners (GPs) can use to facilitate discussion of prognosis with patients who have COPD.

DESIGN OF STUDY

Telephone interviews of 15 GPs and five respiratory consultants on the topic of discussing prognosis with patients who have severe COPD.

SETTING

Participating doctors worked in the Auckland region of New Zealand.

METHOD

GPs and consultants were selected purposively to detect unique and shared patterns from diversity in how prognosis is discussed with patients with severe COPD. An interview guide was developed from a literature review and results of our earlier postal survey of GPs. Transcripts of audiotaped interviews were analysed independently and then together by three authors, using a general inductive approach.

RESULTS

Seven strategies were identified that GPs had used or could use to facilitate discussion of prognosis with patients with COPD. These were: be aware of implications of diagnosis; use uncertainty to ease discussion; build relationship with patients; be caring and respectful; begin discussion early in disease course; identify and use opportunities to discuss prognosis; and work as a team.

CONCLUSION

A number of suggested strategies can be used to facilitate discussion of prognosis with patients who have severe COPD.

Synthesis of a highly substituted N(6)-linked immobilized NAD(+) derivative using a rapid solid-phase modular approach: suitability for use with the kinetic locking-on tactic for bioaffinity purification of NAD(+)-dependent dehydrogenases

This study is concerned with further development of the kinetic locking-on strategy for bioaffinity purification of NAD(+)-dependent dehydrogenases. Specifically, the synthesis of highly substituted N(6)-linked immobilized NAD(+) derivatives is described using a rapid solid-phase modular approach. Other modifications of the N(6)-linked immobilized NAD(+) derivative include substitution of the hydrophobic diaminohexane spacer arm with polar spacer arms (9 and 19.5 A) in an attempt to minimize nonbiospecific interactions. Analysis of the N(6)-linked NAD(+) derivatives confirm (i) retention of cofactor activity upon immobilization (up to 97%); (ii) high total substitution levels and high percentage accessibility levels when compared to S(6)-linked immobilized NAD(+) derivatives (also synthesized with polar spacer arms); (iii) short production times when compared to the preassembly approach to synthesis. Model locking-on bioaffinity chromatographic studies were carried out with bovine heart l-lactate dehydrogenase (l-LDH, EC 1.1.1.27), bakers yeast alcohol dehydrogenase (YADH, EC 1.1.1.1) and Sporosarcinia sp. l-phenylalanine dehydrogenase (l-PheDH, EC 1.4.1.20), using oxalate, hydroxylamine, and d-phenylalanine, respectively, as locking-on ligands. Surprisingly, two of these test NAD(+)-dependent dehydrogenases (lactate and alcohol dehydrogenase) were found to have a greater affinity for the more lowly substituted S(6)-linked immobilized cofactor derivatives than for the new N(6)-linked derivatives. In contrast, the NAD(+)-dependent phenylalanine dehydrogenase showed no affinity for the S(6)-linked immobilized NAD(+) derivative, but was locked-on strongly to the N(6)-linked immobilized derivative. That this locking-on is biospecific is confirmed by the observation that the enzyme failed to lock-on to an analogous N(6)-linked immobilized NADP(+) derivative in the presence of d-phenylalanine. This differential locking-on of NAD(+)-dependent dehydrogenases to N(6)-linked and S(6)-linked immobilized NAD(+) derivatives cannot be explained in terms of final accessible substitutions levels, but suggests fundamental differences in affinity of the three test enzymes for NAD(+) immobilized via N(6)-linkage as compared to thiol-linkage.

A "stripping" ligand tactic for use with the kinetic locking-on strategy: its use in the resolution and bioaffinity chromatographic purification of NAD(+)-dependent dehydrogenases

The kinetic locking-on strategy utilizes soluble analogues of the target enzymes' specific substrate to promote selective adsorption of individual NAD(+)-dependent dehydrogenases on their complementary immobilized cofactor derivative. Application of this strategy to the purification of NAD(+)-dependent dehydrogenases from crude extracts has proven that it can yield bioaffinity systems capable of producing one-chromatographic-step purifications with yields approaching 100%. However, in some cases the purified enzyme preparation was found to be contaminated with other proteins weakly bound to the immobilized cofactor derivative through binary complex formation and/or nonspecific interactions, which continuously "dribbled" off the matrix during the chromatographic procedure. The fact that this problem can be overcome by including a short pulse of 5'-AMP (stripping ligand) in the irrigant a couple of column volumes prior to the discontinuation of the specific substrate analogue (locking-on ligand) is clear from the results presented in this report. The general effectiveness of this auxiliary tactic has been assessed using model studies and through incorporation into an actual purification from a crude cellular extract. The results confirm the usefulness of the stripping-ligand tactic for the resolution and purification of NAD(+)-dependent dehydrogenases when using the locking-on strategy. These studies have been carried out using bovine liver glutamate dehydrogenase (GDH, EC 1.4.1.3), yeast alcohol dehydrogenase (YADH, EC 1.1.1.1), porcine heart mitochondrial malate dehydrogenase (mMDH, EC 1.1.1.37), and bovine heart L-lactate dehydrogenase (l-LDH, EC 1.1.1.27).

Effect of accessible immobilized NAD(+) concentration on the bioaffinity chromatographic behavior of NAD(+)-dependent dehydrogenases using the kinetic locking-on strategy

In preparation for studies aimed at establishing the relationship between immobilized NAD(+) concentration and the concentration of soluble locking-on ligand required to promote biospecific adsorption of NAD(+)-dependent dehydrogenases to immobilized NAD(+) derivatives (the "locking-on" strategy), two approaches were evaluated for varying substitution levels: (i) suitable dilution of the affinity matrix with unsubstituted Sepharose 4B and (ii) direct coupling of the required ligand concentration to the inert matrix. The latter approach was found to be the preferable strategy for evaluation of the locking-on tactic because it produced a more homogeneous distribution of immobilized NAD(+) concentration. Affinity chromatographic studies using S(6)-linked NAD(+) derivatives synthesized to various substitution levels showed that the total accessible immobilized NAD(+) concentration has a direct effect on the locking-on behavior of pyridine nucleotide-dependent dehydrogenases. The one-chromatographic-step bioaffinity purification of l-lactate dehydrogenase (L-LDH, EC 1.1.1.27) from bovine heart illustrates the potential of the locking-on strategy for protein purification applications.

The kinetic locking-on strategy for bioaffinity purification: further studies with bovine liver glutamate dehydrogenase

The locking-on strategy uses soluble analogues of the enzymes specific substrate to produce biospecific adsorption of individual NAD(P)(+)-dependent dehydrogenases on immobilized NAD(P)(+) derivatives, which is so selective that a single enzyme activity can be purified from crude cellular extracts in a single chromatographic step with yields approaching 100%. However, attempts to further develop and apply this strategy to the biospecific chromatographic purification of a range of NAD(P)(+)-dependent dehydrogenases revealed some anomalous chromatographic behavior and certain unexplained phenomenon. Much of this can be attributed to nonbiospecific interference effects. Identification and elimination of this interference is discussed in the present study focusing on bovine liver glutamate dehydrogenase (GDH; EC 1.4.1.3) as the "test" enzyme. Results further confirm the potential of the locking-on strategy for the rapid purification of NAD(P)(+)-dependent dehydrogenases and provide further insight into the parameters which should be considered during the development of a truly biospecific affinity chromatographic system based on the locking-on strategy. The kinetic mechanism of bovine liver GDH has been the topic of much controversy with some reports advocating a sequential ordered mechanism of substrate binding and others reporting a sequential random mechanism. Since the kinetic locking-on strategy is dependent on the target NAD(P)(+)-dependent dehydrogenase having an ordered sequential mechanism of substrate binding, the bioaffinity chromatographic behavior of bovine liver GDH using the locking-on tactic suggests that this enzyme has an ordered sequential mechanism of substrate binding under a variety of experimental conditions when NAD(+) is used as cofactor.

A kinetic locking-on strategy for bioaffinity purification: further studies with alcohol dehydrogenase

The kinetic locking-on strategy improves the selectivity of protein purification procedures based on immobilized cofactor derivatives through use of enzyme-specific substrate analogues in irrigants to promote biospecific adsorption. This paper describes the development and application of this strategy to the one-chromatographic step affinity purification of NAD(P)+-dependent alcohol dehydrogenases using 8'-azo-linked immobilized NAD(P)+, S6-linked and N6-linked immobilized NAD+, and N6-linked immobilized NADP+ derivatives. These studies were carried out using alcohol dehydrogenases from Saccharomyces cerevisiae (YADH, EC 1.1.1.1), equine liver (HLADH, EC 1.1.1.1), and Thermoanaerobium brockii (TBADH, EC 1.1.1.2). The results reveal that the factors which require careful consideration before development of a truly biospecific system based on the locking-on strategy include: (i) the stability of the immobilized cofactor derivative; (ii) the spacer-arm composition of the affinity derivative; (iii) the accessible immobilized cofactor concentration; (iv) the soluble locking-on ligand concentration; (v) the dissociation constant of locking-on ligand, and (vi) the identification and elimination of nonbiospecific interference. The S6-linked immobilized NAD+ derivative (synthesized with a hydrophilic spacer arm) proved to be the most suitable of the affinity adsorbents investigated in the present study for use with the locking-on strategy. This conclusion was based primarily on the observations that this affinity adsorbent was stable, retained cofactor activity with the "test" enzymes under study, and was not prone to nonbiospecific interactions. Using this immobilized derivative in conjunction with the locking-on strategy, alcohol dehydrogenase from Saccharomyces cerevisiae was purified to electrophoretic homogeneity in a single affinity chromatographic step.

Biospecific affinity chromatographic purification of octopine dehydrogenase from molluscs

The development of a biospecific affinity chromatographic method for the purification of octopine dehydrogenase from molluscs is described. The method utilizes immobilized NAD+ derivatives in conjunction with soluble specific substrates to promote binding. Using this method, octopine dehydrogenase has been purified to electrophoretic homogeneity in a single chromatographic step from three different marine invertebrate sources [the queen scallop, Chlamys opercularis (adductor muscle), the great scallop, Pecten maximus (adductor muscle), and the squid Loligo vulgaris (mantle muscle)]. However, the system is not applicable to the purification of octopine dehydrogenase from some other marine invertebrate sources investigated (the mussel Mytilus edulis and the topshell Monodonta lineata).

Further studies on the bioaffinity chromatography of NAD(+)-dependent dehydrogenases using the locking-on effect

Previous studies have capitalized on ordered kinetic mechanisms in the design of biospecific affinity chromatographic methods for highly efficient purifications and mechanistic studies of enzymes. The most direct tactic has been the use of immobilised analogues of the following, usually enzyme-specific substrates, e.g., lactate/pyruvate in the case of lactate dehydrogenase for which NAD+ is the leading substrate. Such immobilised specific substrates are, however, often difficult or impossible to synthesise. The locking-on strategy reverses the tactic by using the more accessible immobilised leading substrate, immobilised NAD+, as adsorbent with soluble analogues of the enzyme-specific ligands (e.g., lactate in the case of lactate dehydrogenase) providing a substantial reinforcement of biospecific adsorption sufficient to effect adsorptive selection of an enzyme from a group of enzymes such as the NAD(+)-specific enzymes. The value of this approach is demonstrated using model studies with lactate dehydrogenase (LDH, EC 1.1.1.27), alcohol dehydrogenase (ADH, EC 1.1.1.1), glutamate dehydrogenase (GDH, EC 1.4.1.3) and malate dehydrogenase (MDH, EC 1.1.1.37). Purification of bovine liver GDH in high yield from crude extracts is described using the tactic.