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1.
NPJ Regen Med ; 8(1): 1, 2023 Jan 06.
Article in English | MEDLINE | ID: mdl-36609660

ABSTRACT

Despite the substantial impact of skin scarring on patients and the healthcare system, there is a lack of strategies to prevent scar formation, let alone methods to remodel mature scars. Here, we took a unique approach inspired by how healthy hairbearing skin undergoes physiological remodelling during the regular cycling of hair follicles. In this pilot clinical study, we tested if hair follicles transplanted into human scars can facilitate tissue regeneration and actively remodel fibrotic tissue, similar to how they remodel the healthy skin. We collected full-thickness skin biopsies and compared the morphology and transcriptional signature of fibrotic tissue before and after transplantation. We found that hair follicle tranplantation induced an increase in the epidermal thickness, interdigitation of the epidermal-dermal junction, dermal cell density, and blood vessel density. Remodelling of collagen type I fibres reduced the total collagen fraction, the proportion of thick fibres, and their alignment. Consistent with these morphological changes, we found a shift in the cytokine milieu of scars with a long-lasting inhibition of pro-fibrotic factors TGFß1, IL13, and IL-6. Our results show that anagen hair follicles can attenuate the fibrotic phenotype, providing new insights for developing regenerative approaches to remodel mature scars.

2.
Arterioscler Thromb Vasc Biol ; 43(2): 323-329, 2023 02.
Article in English | MEDLINE | ID: mdl-36453276

ABSTRACT

BACKGROUND: Reprogramming of monocytes and macrophage manifests in hyperinflammatory responses and chronification of inflammation in atherosclerosis. Recent studies focused on epigenetic, transcriptional, and metabolic alterations that characterize trained immunity. However, the underlying effector mechanisms driving the hyperinflammatory response of reprogrammed macrophages remain unclear. We hypothesized that the plasma membrane of atherosclerotic lesion macrophages undergoes reprogramming to maintain inflammarafts, enlarged lipid rafts (LR) serving as a platform for assembly of inflammatory receptor complexes. METHODS: Single-cell suspensions from the aortae of Western diet-fed Ldlr-/- mice were gated for BODIPY-high foamy and BODIPY-low nonfoamy F4/80 macrophages by flow cytometry. Inflammarafts were characterized by increased levels of LR, TLR4 (toll-like receptor-4) localization to LR, TLR4 dimers, and the proximity between TLR2, TLR1, and CD36. In a cellular model of trained immunity, LR, TLR4 dimers, and the inflammatory response were measured in bone marrow-derived macrophages subjected to a 24-hour treatment with LPS (lipopolysaccharide) or OxLDL (oxidized low-density lipoprotein), followed by a 6-day wash-out period. RESULTS: Nonfoamy macrophages, which constituted ≈40% of macrophages in atherosclerotic lesions, expressed significantly higher levels of LR and TLR4 dimers, as well as proximity ligation signals for TLR4-LR, TLR2-CD36, and TLR2-TLR1 complexes, compared with foamy macrophages. These inflammaraft measures associated, to a different degree, with plasma cholesterol and inflammatory cytokines, as well as the size of the atherosclerotic lesions and necrotic cores. The bone marrow-derived macrophages trained with LPS simulated nonfoamy atherosclerotic lesion macrophages and continued to express inflammarafts and inflammatory genes for 6 days after LPS removal and displayed a hyperinflammatory response to Pam3CSK4, a TLR2/TLR1 agonist. OxLDL-exposed, lipid-laden macrophages did not express inflammarafts. CONCLUSIONS: Our data support the hypothesis that persistent inflammarafts in nonfoamy macrophages in atherosclerotic lesions serve as effectors of macrophage reprogramming into a hyperinflammatory phenotype.


Subject(s)
Atherosclerosis , Foam Cells , Mice , Animals , Foam Cells/pathology , Toll-Like Receptor 4/genetics , Toll-Like Receptor 4/metabolism , Lipopolysaccharides , Toll-Like Receptor 2/genetics , Toll-Like Receptor 2/metabolism , Toll-Like Receptor 1/metabolism , Macrophages/metabolism , Atherosclerosis/pathology , Lipoproteins, LDL/metabolism , CD36 Antigens/genetics , CD36 Antigens/metabolism
3.
Proc Natl Acad Sci U S A ; 119(31): e2122563119, 2022 08 02.
Article in English | MEDLINE | ID: mdl-35858384

ABSTRACT

The elephant's trunk is multifunctional: It must be flexible to wrap around vegetation, but tough to knock down trees and resist attack. How can one appendage satisfy both constraints? In this combined experimental and theoretical study, we challenged African elephants to reach far-away objects with only horizontal extensions of their trunk. Surprisingly, the trunk does not extend uniformly, but instead exhibits a dorsal "joint" that stretches 15% more than the corresponding ventral section. Using material testing with the skin of a deceased elephant, we show that the asymmetry is due in part to patterns of the skin. The dorsal skin is folded and 15% more pliable than the wrinkled ventral skin. Skin folds protect the dorsal section and stretch to facilitate downward wrapping, the most common gripping style when picking up items. The elephant's skin is also sufficiently stiff to influence its mechanics: At the joint, the skin requires 13 times more energy to stretch than the corresponding length of muscle. The use of wrinkles and folds to modulate stiffness may provide a valuable concept for both biology and soft robotics.


Subject(s)
Elephants , Nose , Skin Physiological Phenomena , Skin , Animals , Elephants/anatomy & histology , Elephants/physiology , Nose/anatomy & histology , Nose/physiology
4.
Exp Dermatol ; 30(12): 1829-1833, 2021 12.
Article in English | MEDLINE | ID: mdl-34173264

ABSTRACT

Skin injuries remain a persistent problem for users of lower-limb prostheses despite sustained progress in prosthesis design. One factor limiting the prevention of skin injuries is that skin on the residual limb is not suited to bear the mechanical loads of ambulation. One part of the body that is suited to this task is the sole of the foot. Here, we propose a novel strategy to actively augment skin's tolerance to load, increasing its resistance to mechanically induced injuries. We hypothesise that the load tolerance of skin can be augmented by autologous transplantation of plantar fibroblasts into the residual limb dermis. We expect that introducing plantar fibroblasts will induce the overlying keratinocytes to express plantar-specific keratins leading to a tougher epidermis. Using a computational finite element model of a weight-bearing residual limb, we estimate that skin deformation (a key driver of pressure ulcer injuries) could be halved by reprogramming skin to a plantar-like phenotype. We believe this strategy could yield new progress in pressure ulcer prevention for amputees, facilitating rehabilitation and improving quality of life for patients.


Subject(s)
Amputees/rehabilitation , Fibroblasts/transplantation , Prosthesis Design , Skin/injuries , Computer Simulation , Forefoot, Human , Humans
5.
J Exp Med ; 218(7)2021 07 05.
Article in English | MEDLINE | ID: mdl-33970188

ABSTRACT

Neuroinflammation is a major component in the transition to and perpetuation of neuropathic pain states. Spinal neuroinflammation involves activation of TLR4, localized to enlarged, cholesterol-enriched lipid rafts, designated here as inflammarafts. Conditional deletion of cholesterol transporters ABCA1 and ABCG1 in microglia, leading to inflammaraft formation, induced tactile allodynia in naive mice. The apoA-I binding protein (AIBP) facilitated cholesterol depletion from inflammarafts and reversed neuropathic pain in a model of chemotherapy-induced peripheral neuropathy (CIPN) in wild-type mice, but AIBP failed to reverse allodynia in mice with ABCA1/ABCG1-deficient microglia, suggesting a cholesterol-dependent mechanism. An AIBP mutant lacking the TLR4-binding domain did not bind microglia or reverse CIPN allodynia. The long-lasting therapeutic effect of a single AIBP dose in CIPN was associated with anti-inflammatory and cholesterol metabolism reprogramming and reduced accumulation of lipid droplets in microglia. These results suggest a cholesterol-driven mechanism of regulation of neuropathic pain by controlling the TLR4 inflammarafts and gene expression program in microglia and blocking the perpetuation of neuroinflammation.


Subject(s)
Cholesterol/metabolism , Microglia/metabolism , Neuralgia/metabolism , Spinal Cord/metabolism , ATP Binding Cassette Transporter 1/metabolism , ATP Binding Cassette Transporter, Subfamily G, Member 1/metabolism , Animals , Biological Transport/physiology , Cell Line , HEK293 Cells , Humans , Inflammation/metabolism , Male , Membrane Microdomains/metabolism , Mice , Mice, Inbred C57BL , Protein Binding/physiology , Signal Transduction/physiology
6.
Nat Aging ; 1(1): 73-86, 2021 01.
Article in English | MEDLINE | ID: mdl-33796866

ABSTRACT

Protein restricted (PR) diets promote health and longevity in many species. While the precise components of a PR diet that mediate the beneficial effects to longevity have not been defined, we recently showed that many metabolic effects of PR can be attributed to reduced dietary levels of the branched-chain amino acids (BCAAs) leucine, isoleucine, and valine. Here, we demonstrate that restricting dietary BCAAs increases the survival of two different progeroid mouse models, delays frailty and promotes the metabolic health of wild-type C57BL/6J mice when started in midlife, and leads to a 30% increase in lifespan and a reduction in frailty in male, but not female, wild-type mice when fed lifelong. Our results demonstrate that restricting dietary BCAAs can increase healthspan and longevity in mice, and suggest that reducing dietary BCAAs may hold potential as a translatable intervention to promote healthy aging.


Subject(s)
Amino Acids, Branched-Chain , Frailty , Female , Male , Animals , Mice , Amino Acids, Branched-Chain/metabolism , Longevity , Frailty/prevention & control , Health Promotion , Mice, Inbred C57BL , Diet
7.
Arterioscler Thromb Vasc Biol ; 41(2): e82-e96, 2021 02.
Article in English | MEDLINE | ID: mdl-33356389

ABSTRACT

OBJECTIVE: Atherosclerotic lesions are often characterized by accumulation of OxLDL (oxidized low-density lipoprotein), which is associated with vascular inflammation and lesion vulnerability to rupture. Extracellular AIBP (apolipoprotein A-I binding protein; encoded by APOA1BP gene), when secreted, promotes cholesterol efflux and regulates lipid rafts dynamics, but its role as an intracellular protein in mammalian cells remains unknown. The aim of this work was to determine the function of intracellular AIBP in macrophages exposed to OxLDL and in atherosclerotic lesions. Approach and Results: Using a novel monoclonal antibody against human and mouse AIBP, which are highly homologous, we demonstrated robust AIBP expression in human and mouse atherosclerotic lesions. We observed significantly reduced autophagy in bone marrow-derived macrophages, isolated from Apoa1bp-/- compared with wild-type mice, which were exposed to OxLDL. In atherosclerotic lesions from Apoa1bp-/- mice subjected to Ldlr knockdown and fed a Western diet, autophagy was reduced, whereas apoptosis was increased, when compared with that in wild-type mice. AIBP expression was necessary for efficient control of reactive oxygen species and cell death and for mitochondria quality control in macrophages exposed to OxLDL. Mitochondria-localized AIBP, via its N-terminal domain, associated with E3 ubiquitin-protein ligase PARK2 (Parkin), MFN (mitofusin)1, and MFN2, but not BNIP3 (Bcl2/adenovirus E1B 19-kDa-interacting protein-3), and regulated ubiquitination of MFN1 and MFN2, key components of mitophagy. CONCLUSIONS: These data suggest that intracellular AIBP is a new regulator of autophagy in macrophages. Mitochondria-localized AIBP augments mitophagy and participates in mitochondria quality control, protecting macrophages against cell death in the context of atherosclerosis.


Subject(s)
Aortic Diseases/metabolism , Atherosclerosis/metabolism , Lipoproteins, LDL/toxicity , Macrophages/drug effects , Mitochondria/drug effects , Mitophagy/drug effects , Phosphoproteins/metabolism , Racemases and Epimerases/metabolism , Animals , Aortic Diseases/genetics , Aortic Diseases/pathology , Apoptosis/drug effects , Atherosclerosis/genetics , Atherosclerosis/pathology , Autophagosomes/drug effects , Autophagosomes/metabolism , Autophagosomes/pathology , Autophagy-Related Proteins/genetics , Autophagy-Related Proteins/metabolism , Carotid Artery Diseases/metabolism , Carotid Artery Diseases/pathology , Disease Models, Animal , HEK293 Cells , Hep G2 Cells , Humans , Macrophages/metabolism , Macrophages/pathology , Male , Mice, Inbred C57BL , Mice, Knockout , Mitochondria/metabolism , Mitochondria/pathology , Mitochondrial Proteins/genetics , Mitochondrial Proteins/metabolism , Phosphoproteins/genetics , Racemases and Epimerases/genetics , Reactive Oxygen Species/metabolism , Signal Transduction
8.
Dev Dyn ; 250(3): 450-464, 2021 03.
Article in English | MEDLINE | ID: mdl-32776603

ABSTRACT

BACKGROUND: Abnormal fetal movements are implicated in joint pathologies such as arthrogryposis and developmental dysplasia of the hip (DDH). Experimentally induced paralysis disrupts joint cavitation and morphogenesis leading to postnatal abnormalities. However, the developmental window(s) most sensitive to immobility-and therefore the best time for intervention-have never been identified. Here, we systematically vary the timing and duration of paralysis during early chick hip joint development. We then test whether external manipulation of immobilized limbs can mitigate the effects of immobility. RESULTS: Timing of paralysis affected the level of disruption to joints, with paralysis periods between embryonic days 4 and 7 most detrimental. Longer paralysis periods produced greater disruption in terms of failed cavitation and abnormal femoral and acetabular geometry. External manipulation of an immobilized limb led to more normal morphogenesis and cavitation compared to un-manipulated limbs. CONCLUSIONS: Temporary paralysis is detrimental to joint development, particularly during days 4 to 7. Developmental processes in the very early stages of joint development may be critical to DDH, arthrogryposis, and other joint pathologies. The developing limb has the potential to recover from periods of immobility, and external manipulation provides an innovative avenue for prevention and treatment of developmental joint pathologies.


Subject(s)
Acetabulum/embryology , Hip Joint/embryology , Morphogenesis , Paralysis , Animals , Chick Embryo
9.
J Invest Dermatol ; 140(5): 1075-1084.e11, 2020 05.
Article in English | MEDLINE | ID: mdl-31682842

ABSTRACT

In skin homeostasis, dermal fibroblasts are responsible for coordinating the migration and differentiation of overlying epithelial keratinocytes. As hairy skin heals faster than nonhairy skin, we took bio-inspiration from the follicle and hypothesized that follicular fibroblasts would accelerate skin re-epithelialization after injury faster than interfollicular fibroblasts. Using both in vitro and ex vivo models of human skin wound closure, we found that hair follicle dermal papilla fibroblasts could accelerate closure of in vitro scratch wounds by 1.8-fold and epithelial growth capacity by 1.5-fold compared with controls (P < 0.05). We used a cytokine array to determine how the dermal papilla fibroblasts were eliciting this effect and identified two cytokines, sAXL and CCL19, that are released at significantly higher levels by follicular fibroblasts than by interfollicular subtypes. Using sAXL and CCL19 individually, we found that they could also increase closure of epithelial cells in a scratch wound by 1.2- and 1.5-fold, respectively, compared with controls (P < 0.05). We performed an unbiased transcriptional analysis, combined with pathway analysis, and postulate that sAXL accelerates wound closure by promoting migration and inhibiting epithelial differentiation of skin keratinocytes. Long term, we believe these results can be exploited to accelerate wound closure of human skin in vivo.


Subject(s)
Epithelial Cells/physiology , Fibroblasts/physiology , Hair Follicle/physiology , Keratinocytes/physiology , Skin/pathology , Wounds and Injuries/metabolism , Adult , Bodily Secretions , Cell Differentiation , Cell Movement , Cell Proliferation , Cells, Cultured , Chemokine CCL19/metabolism , Humans , Male , Middle Aged , Organ Culture Techniques , Proteome , Proto-Oncogene Proteins/metabolism , Receptor Protein-Tyrosine Kinases/metabolism , Skin/metabolism , Wound Healing , Wounds and Injuries/pathology , Axl Receptor Tyrosine Kinase
11.
Sci Adv ; 5(10): eaay0244, 2019 10.
Article in English | MEDLINE | ID: mdl-31633031

ABSTRACT

Plantar skin on the soles of the feet has a distinct morphology and composition that is thought to enhance its tolerance to mechanical loads, although the individual contributions of morphology and composition have never been quantified. Here, we combine multiscale mechanical testing and computational models of load bearing to quantify the mechanical environment of both plantar and nonplantar skin under load. We find that morphology and composition play distinct and complementary roles in plantar skin's load tolerance. More specifically, the thick stratum corneum provides protection from stress-based injuries such as skin tears and blisters, while epidermal and dermal compositions provide protection from deformation-based injuries such as pressure ulcers. This work provides insights into the roles of skin morphology and composition more generally and will inform the design of engineered skin substitutes as well as the etiology of skin injury.


Subject(s)
Skin/pathology , Stress, Mechanical , Collagen Type I/chemistry , Collagen Type I/metabolism , Epidermis/pathology , Humans , Microscopy, Atomic Force , Skin/injuries , Skin/metabolism
12.
Sci Rep ; 9(1): 67, 2019 01 11.
Article in English | MEDLINE | ID: mdl-30635612

ABSTRACT

Obesity and type 2 diabetes are increasing in prevalence around the world, and there is a clear need for new and effective strategies to promote metabolic health. A low protein (LP) diet improves metabolic health in both rodents and humans, but the mechanisms that underlie this effect remain unknown. The gut microbiome has recently emerged as a potent regulator of host metabolism and the response to diet. Here, we demonstrate that a LP diet significantly alters the taxonomic composition of the gut microbiome at the phylum level, altering the relative abundance of Actinobacteria, Bacteroidetes, and Firmicutes. Transcriptional profiling suggested that any impact of the microbiome on liver metabolism was likely independent of the microbiome-farnesoid X receptor (FXR) axis. We therefore tested the ability of a LP diet to improve metabolic health following antibiotic ablation of the gut microbiota. We found that a LP diet promotes leanness, increases energy expenditure, and improves glycemic control equally well in mice treated with antibiotics as in untreated control animals. Our results demonstrate that the beneficial effects of a LP diet on glucose homeostasis, energy balance, and body composition are unlikely to be mediated by diet-induced changes in the taxonomic composition of the gut microbiome.


Subject(s)
Amino Acids/metabolism , Biota , Diet/methods , Intestines/microbiology , Metabolism , Animals , Gene Expression Profiling , Mice
13.
PLoS One ; 15(1): e0227064, 2019.
Article in English | MEDLINE | ID: mdl-31899778

ABSTRACT

When immobile or neuropathic patients are supported by beds or chairs, their soft tissues undergo deformations that can cause pressure ulcers. Current support surfaces that redistribute under-body pressures at vulnerable body sites have not succeeded in reducing pressure ulcer prevalence. Here we show that adding a supporting lateral pressure can counter-act the deformations induced by under-body pressure, and that this 'pressure equalisation' approach is a more effective way to reduce ulcer-inducing deformations than current approaches based on redistributing under-body pressure. A finite element model of the seated pelvis predicts that applying a lateral pressure to the soft tissue reduces peak von Mises stress in the deep tissue by a factor of 2.4 relative to a standard cushion (from 113 kPa to 47 kPa)-a greater effect than that achieved by using a more conformable cushion, which reduced von Mises stress to 75 kPa. Combining both a conformable cushion and lateral pressure reduced peak von Mises stresses to 25 kPa. The ratio of peak lateral pressure to peak under-body pressure was shown to regulate deep tissue stress better than under-body pressure alone. By optimising the magnitude and position of lateral pressure, tissue deformations can be reduced to that induced when suspended in a fluid. Our results explain the lack of efficacy in current support surfaces and suggest a new approach to designing and evaluating support surfaces: ensuring sufficient lateral pressure is applied to counter-act under-body pressure.


Subject(s)
Equipment Design , Pressure Ulcer/prevention & control , Therapy, Soft Tissue/methods , Biomechanical Phenomena , Buttocks , Humans , Pelvis , Pressure
14.
J Lipid Res ; 60(2): 436-445, 2019 02.
Article in English | MEDLINE | ID: mdl-30563909

ABSTRACT

Atherosclerosis is associated with increased lipid peroxidation, leading to generation of multiple oxidation-specific epitopes (OSEs), contributing to the pathogenesis of atherosclerosis and its clinical manifestation. Oxidized cholesteryl esters (OxCEs) are a major class of OSEs found in human plasma and atherosclerotic tissue. To evaluate OxCEs as a candidate biomarker, we generated a novel mouse monoclonal Ab (mAb) specific to an OxCE modification of proteins. The mAb AG23 (IgG1) was raised in C57BL6 mice immunized with OxCE-modified keyhole limpet hemocyanin, and hybridomas were screened against OxCE-modified BSA. This method ensures mAb specificity to the OxCE modification, independent of a carrier protein. AG23 specifically stained human carotid artery atherosclerotic lesions. An ELISA method, with AG23 as a capture and either anti-apoAI or anti-apoB-100 as the detection Abs, was developed to assay apoAI and apoB-100 lipoproteins that have one or more OxCE epitopes. OxCE-apoA or OxCE-apoB did not correlate with the well-established oxidized phospholipid-apoB biomarker. In a cohort of subjects treated with atorvastatin, OxCE-apoA was significantly lower than in the placebo group, independent of the apoAI levels. These results suggest the potential diagnostic utility of a new biomarker assay to measure OxCE-modified lipoproteins in patients with CVD.


Subject(s)
Antibodies, Monoclonal/immunology , Apolipoprotein A-I/metabolism , Apolipoprotein B-100/metabolism , Cholesterol Esters/blood , Cholesterol Esters/metabolism , Enzyme-Linked Immunosorbent Assay/methods , Animals , Cholesterol Esters/immunology , Humans , Mice , Oxidation-Reduction
15.
J Lipid Res ; 59(5): 854-863, 2018 05.
Article in English | MEDLINE | ID: mdl-29559522

ABSTRACT

Apolipoprotein A-I binding protein (AIBP) has been shown to augment cholesterol efflux from endothelial cells and macrophages. In zebrafish and mice, AIBP-mediated regulation of cholesterol levels in the plasma membrane of endothelial cells controls angiogenesis. The goal of this work was to evaluate metabolic changes and atherosclerosis in AIBP loss-of-function and gain-of-function animal studies. Here, we show that Apoa1bp-/-Ldlr-/- mice fed a high-cholesterol, high-fat diet had exacerbated weight gain, liver steatosis, glucose intolerance, hypercholesterolemia, hypertriglyceridemia, and larger atherosclerotic lesions compared with Ldlr-/- mice. Feeding Apoa1bp-/-Ldlr-/- mice a high-cholesterol, normal-fat diet did not result in significant differences in lipid levels or size of atherosclerotic lesions from Ldlr-/- mice. Conversely, adeno-associated virus-mediated overexpression of AIBP reduced hyperlipidemia and atherosclerosis in high-cholesterol, high-fat diet-fed Ldlr-/- mice. Injections of recombinant AIBP reduced aortic inflammation in Ldlr-/- mice fed a short high-cholesterol, high-fat diet. Conditional overexpression of AIBP in zebrafish also reduced diet-induced vascular lipid accumulation. In experiments with isolated macrophages, AIBP facilitated cholesterol efflux to HDL, reduced lipid rafts content, and inhibited inflammatory responses to lipopolysaccharide.jlr Our data demonstrate that AIBP confers protection against diet-induced metabolic abnormalities and atherosclerosis.


Subject(s)
Atherosclerosis/metabolism , Carrier Proteins/metabolism , Metabolic Syndrome/metabolism , Phosphoproteins/metabolism , Animals , Inflammation/drug therapy , Inflammation/metabolism , Lipopolysaccharides/antagonists & inhibitors , Lipopolysaccharides/pharmacology , Mice , Mice, Inbred C57BL , Mice, Knockout , Phosphoproteins/deficiency , Racemases and Epimerases , Receptors, LDL/deficiency , Receptors, LDL/metabolism
16.
Opt Express ; 24(21): 24483-24494, 2016 Oct 17.
Article in English | MEDLINE | ID: mdl-27828176

ABSTRACT

8.4 µm-emitting quantum cascade lasers (QCLs) have been designed to have, right from threshold, both carrier-leakage suppression and miniband-like carrier extraction. The slope-efficiency characteristic temperature T1, the signature of carrier-leakage suppression, is found to be 665 K. Resonant-tunneling carrier extraction from both the lower laser level (ll) and the level below it, coupled with highly effective ll-depopulation provide a very short ll lifetime (~0.12 ps). As a result the laser-transition differential efficiency reaches 89%, and the internal differential efficiency ηid, derived from a variable mirror-loss study, is found to be 86%, in good agreement with theory. A study of 8.8 µm-emitting QCLs also provides an ηid value of 86%. A corrected equation for the external differential efficiency is derived which leads to a fundamental limit of ~90% for the ηid values of mid-infrared QCLs. In turn, the fundamental wallplug-efficiency limits become ~34% higher than previously predicted.

17.
Rev Panam Salud Publica ; 39(5): 299-305, 2016 May.
Article in English | MEDLINE | ID: mdl-27706403

ABSTRACT

Medicines Regulatory Authorities (MRAs) are an essential part of national health systems and are charged with protecting and promoting public health through regulation of medicines. However, MRAs in resource-constrained settings often struggle to provide effective oversight of market entry and use of health commodities. This paper proposes a regulatory value chain model (RVCM) that policymakers and regulators can use as a conceptual framework to guide investments aimed at strengthening regulatory systems. The RVCM incorporates nine core functions of MRAs into five modules: (i) clear guidelines and requirements; (ii) control of clinical trials; (iii) market authorization of medical products; (iv) pre-market quality control; and (v) post-market activities. Application of the RVCM allows national stakeholders to identify and prioritize investments according to where they can add the most value to the regulatory process. Depending on the economy, capacity, and needs of a country, some functions can be elevated to a regional or supranational level, while others can be maintained at the national level. In contrast to a "one size fits all" approach to regulation in which each country manages the full regulatory process at the national level, the RVCM encourages leveraging the expertise and capabilities of other MRAs where shared processes strengthen regulation. This value chain approach provides a framework for policymakers to maximize investment impact while striving to reach the goal of safe, affordable, and rapidly accessible medicines for all.


Subject(s)
Legislation, Drug , Public Health Administration , Clinical Trials as Topic/standards , Developing Countries , Guidelines as Topic , Health Resources , Humans , Marketing of Health Services , Product Surveillance, Postmarketing , Public Health , Quality Control
18.
Rev Panam Salud Publica ; 39(5), mayo 2016
Article in English | PAHO-IRIS | ID: phr-28520

ABSTRACT

Medicines Regulatory Authorities (MRAs) are an essential part of national health systems and are charged with protecting and promoting public health through regulation of medicines. However, MRAs in resource-constrained settings often struggle to provide effective oversight of market entry and use of health commodities. This paper proposes a regulatory value chain model (RVCM) that policymakers and regulators can use as a conceptual framework to guide investments aimed at strengthening regulatory systems. The RVCM incorporates nine core functions of MRAs into five modules: (i) clear guidelines and requirements; (ii) control of clinical trials; (iii) market authorization of medical products; (iv) pre-market quality control; and (v) post-market activities. Application of the RVCM allows national stakeholders to identify and prioritize investments according to where they can add the most value to the regulatory process. Depending on the economy, capacity, and needs of a country, some functions can be elevated to a regional or supranational level, while others can be maintained at the national level. In contrast to a “one size fits all” approach to regulation in which each country manages the full regulatory process at the national level, the RVCM encourages leveraging the expertise and capabilities of other MRAs where shared processes strengthen regulation. This value chain approach provides a framework for policymakers to maximize investment impact while striving to reach the goal of safe, affordable, and rapidly accessible medicines for all.


Los organismos de reglamentación farmacéutica son parte esencial de los sistemas nacionales de salud y se encargan de proteger y promover la salud pública mediante la reglamentación en torno a los medicamentos. Sin embargo, en lugares con pocos recursos, estos organismos suelen tener dificultad para supervisar eficazmente la entrada en el mercado y el uso de los productos sanitarios básicos. En el presente artículo se propone un modelo de cadena de valor reglamentaria (MCVR) que los responsables de las políticas y de la reglamentación pueden usar como marco conceptual para guiar las inversiones dirigidas a fortalecer los sistemas reglamentarios. El modelo incorpora en cinco módulos nueve funciones básicas de los organismos de reglamentación farmacéutica: (i) directrices y requisitos inequívocos; (ii) el control de los ensayos clínicos; (iii) la autorización de la comercialización de los productos médicos; (iv) el control de calidad antes de la comercialización; y (v) las actividades posteriores a esta. La aplicación del MCVR les permite a los interesados directos en los países determinar qué inversiones hacen falta y darles la prioridad debida teniendo presente dónde contribuirían en mayor medida a realzar el valor del proceso reglamentario. Si lo permiten la economía, la capacidad y las necesidades de un país, ciertas funciones pueden extenderse al nivel regional o supranacional, mientras que otras pueden seguir siendo nacionales. A diferencia de un método único para todos los casos, en el que cada país administra todo el proceso reglamentario en el nivel nacional, el MCVR promueve el aprovechamiento de la pericia y capacidades de otros organismos de reglamentación farmacéutica en áreas donde los procesos comunes fortalecen la reglamentación. Este método de la cadena de valor les proporciona a los formuladores de las políticas un marco para potenciar al máximo el efecto de las inversiones a la vez que se esfuerzan por lograr el objetivo de poner al alcance de todos medicamentos inocuos, asequibles y rápidamente accesibles.


Subject(s)
Pharmaceutical Preparations , International Cooperation , Legislation, Pharmacy , Americas , Pharmaceutical Preparations , Technical Cooperation , Legislation, Pharmacy , Delivery of Health Care , Quality Assurance, Health Care
19.
Rev. panam. salud pública ; 39(5): 299-305, may. 2016. tab, graf
Article in English | LILACS | ID: biblio-1043189

ABSTRACT

ABSTRACT Medicines Regulatory Authorities (MRAs) are an essential part of national health systems and are charged with protecting and promoting public health through regulation of medicines. However, MRAs in resource-constrained settings often struggle to provide effective oversight of market entry and use of health commodities. This paper proposes a regulatory value chain model (RVCM) that policymakers and regulators can use as a conceptual framework to guide investments aimed at strengthening regulatory systems. The RVCM incorporates nine core functions of MRAs into five modules: (i) clear guidelines and requirements; (ii) control of clinical trials; (iii) market authorization of medical products; (iv) pre-market quality control; and (v) post-market activities. Application of the RVCM allows national stakeholders to identify and prioritize investments according to where they can add the most value to the regulatory process. Depending on the economy, capacity, and needs of a country, some functions can be elevated to a regional or supranational level, while others can be maintained at the national level. In contrast to a "one size fits all" approach to regulation in which each country manages the full regulatory process at the national level, the RVCM encourages leveraging the expertise and capabilities of other MRAs where shared processes strengthen regulation. This value chain approach provides a framework for policymakers to maximize investment impact while striving to reach the goal of safe, affordable, and rapidly accessible medicines for all.(AU)


RESUMEN Los organismos de reglamentación farmacéutica son parte esencial de los sistemas nacionales de salud y se encargan de proteger y promover la salud pública mediante la reglamentación en torno a los medicamentos. Sin embargo, en lugares con pocos recursos, estos organismos suelen tener dificultad para supervisar eficazmente la entrada en el mercado y el uso de los productos sanitarios básicos. En el presente artículo se propone un modelo de cadena de valor reglamentaria (MCVR) que los responsables de las políticas y de la reglamentación pueden usar como marco conceptual para guiar las inversiones dirigidas a fortalecer los sistemas reglamentarios. El modelo incorpora en cinco módulos nueve funciones básicas de los organismos de reglamentación farmacéutica: (i) directrices y requisitos inequívocos; (ii) el control de los ensayos clínicos; (iii) la autorización de la comercialización de los productos médicos; (iv) el control de calidad antes de la comercialización; y (v) las actividades posteriores a esta. La aplicación del MCVR les permite a los interesados directos en los países determinar qué inversiones hacen falta y darles la prioridad debida teniendo presente dónde contribuirían en mayor medida a realzar el valor del proceso reglamentario. Si lo permiten la economía, la capacidad y las necesidades de un país, ciertas funciones pueden extenderse al nivel regional o supranacional, mientras que otras pueden seguir siendo nacionales. A diferencia de un método único para todos los casos, en el que cada país administra todo el proceso reglamentario en el nivel nacional, el MCVR promueve el aprovechamiento de la pericia y capacidades de otros organismos de reglamentación farmacéutica en áreas donde los procesos comunes fortalecen la reglamentación. Este método de la cadena de valor les proporciona a los formuladores de las políticas un marco para potenciar al máximo el efecto de las inversiones a la vez que se esfuerzan por lograr el objetivo de poner al alcance de todos medicamentos inocuos, asequibles y rápidamente accesibles.(AU)


Subject(s)
Pharmaceutical Preparations/standards , Delivery of Health Care/standards , Total Quality Management/policies , Legislation, Pharmacy , Americas , International Cooperation
20.
PLoS One ; 10(10): e0140092, 2015.
Article in English | MEDLINE | ID: mdl-26452263

ABSTRACT

BACKGROUND: The Commission on Investing in Health published its report, GlobalHealth2035, in 2013, estimating an investment case for a grand convergence in health outcomes globally. In support of the drafting of the Sustainable Development Goals (SDGs), we estimate what the grand convergence investment case might achieve-and what investment would be required-by 2030. METHODS AND FINDINGS: Our projection focuses on a sub-set of low-income (LIC) or lower-middle-income countries (LMIC). We start with a country-based (bottom-up) analysis of the costs and impact of scaling up reproductive, maternal, and child health tools, and select HIV and malaria interventions. We then incorporate global (top-down) analyses of the costs and impacts of scaling up existing tools for tuberculosis, additional HIV interventions, the costs to strengthen health systems, and the costs and benefits from scaling up new health interventions over the time horizon of this forecast. These data are then allocated to individual countries to provide an aggregate projection of potential cost and impact at the country level. Finally, incremental costs of R&D for low-income economies and the costs of addressing NTDs are added to provide a global total cost estimate of the investment scenario. RESULTS: Compared with a constant coverage scenario, there would be more than 60 million deaths averted in LIC and 70 million deaths averted in LMIC between 2016 and 2030. For the years 2015, 2020, 2025, and 2030, the incremental costs of convergence in LIC would be (US billion) $24.3, $21.8, $24.7, and $27, respectively; in LMIC, the incremental costs would be (US billion) $34.75, $38.9, $48.7, and $56.3, respectively. CONCLUSION: Key health outcomes in low- and low-middle income countries can significantly converge with those of wealthier countries by 2030, and the notion of a "grand convergence" may serve as a unifying theme for health indicators in the SDGs.


Subject(s)
Developing Countries , Global Health/economics , Health Care Costs/trends , Child Health/trends , Global Health/trends , HIV Infections/economics , HIV Infections/epidemiology , Humans , Malaria/economics , Malaria/epidemiology , Mortality/trends , Socioeconomic Factors , Tuberculosis/economics , Tuberculosis/epidemiology
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