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1.
Early Hum Dev ; 192: 105994, 2024 May.
Article in English | MEDLINE | ID: mdl-38555660

ABSTRACT

BACKGROUND: Lactate accumulation is associated with vigorous exercise, cardiovascular disease and a number of cancers. Digit ratio (2D:4D) has also been linked to oxygen metabolism, myocardial infarction and various cancers. Such similarities suggest the possibility that 2D:4D is a biomarker of lactate. Here, we consider the relationship between 2D:4D and lactate during an incremental cardiopulmonary exercise test. METHOD: The participants were male professional football players. The treadmill test began at a speed of 8 km/h when the first lactate measurement was taken. The speed was increased by 2 km/h every 3.15 min, with measurements at 10, 12, 14 and 16 km/h. RESULTS: There were 72 Caucasian and 7 Black participants, results are reported for the most numerous group. Lactate levels increased with running speed and were not correlated with age, body size or body composition. Median splits of digit ratios (right, left and right-left 2D:4D [Dr-l]) were calculated. In comparison to the Low ratio group, the High ratio group showed higher lactate levels across speeds. Effect sizes varied from very large to huge (right 2D:4D), large (left 2D:4D) and medium (Dr-l). At the individual level, positive correlations between digit ratios and lactate at the five different speeds varied from large (right 2D:4D), medium (left 2D:4D) and small (Dr-l). CONCLUSION: There were large positive associations between right 2D:4D and lactate at all running speeds. We discuss our findings in relation to oxygen metabolism and suggest that 2D:4D may be a biomarker for lactate in the wider context of the latter's importance in health and disease.


Subject(s)
Biomarkers , Exercise Test , Fingers , Lactic Acid , Soccer , Humans , Male , Lactic Acid/blood , Lactic Acid/metabolism , Fingers/anatomy & histology , Adult , Soccer/physiology
2.
Am J Hum Biol ; 36(6): e24047, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38308173

ABSTRACT

INTRODUCTION: Digit ratio (2D:4D: the relative length of the 2nd and 4th digit) is thought to be a negative correlate of prenatal testosterone. The 2D:4D is related to oxygen metabolism, but the precise nature of this relationship is unclear. The purpose of the present study was to consider associations between digit ratios (right 2D:4D, left 2D:4D, right-left 2D:4D [Dr-l]) and VO2max and ventilatory thresholds (VT1 and VT2). METHODS: One hundred and thirty-three Caucasian (n = 133) professional football players competing in Cyprus participated in the study. Players underwent anthropometric measurements, and digit lengths were measured from hand scans. They also completed an incremental cardiopulmonary test to exhaustion on a treadmill. RESULTS: There were negative correlations between digit ratios and VO2max (right 2D:4D, r = -.65; left 2D:4D r = -.37, both p < .0001; Dr-l r = -.30, p = .0005). There were no relationships between digit ratios and VT1. For VT2, there were negative relationships with digit ratios (right 2D:4D, r = -.43, p < .0001; left 2D:4D, r = -.21 and Dr-l, r = -.21, both p = .02). Digit ratios are negatively related to VO2max with large (right 2D:4D) and medium (left 2D:4D, Dr-l) effect sizes. For VT2, there were also negative correlations, which were medium (right 2D:4D) and small (left 2D:4D, Dr-l). CONCLUSION: Our findings may help clarify the relationships between digit ratios and high-intensity actions for extended periods, which are dependent on efficient oxygen metabolism.


Subject(s)
Fingers , Oxygen Consumption , Soccer , Humans , Fingers/anatomy & histology , Fingers/physiology , Male , Adult , Young Adult , Soccer/physiology , Cyprus , Athletes/statistics & numerical data , Adolescent
3.
Int J Sports Physiol Perform ; 18(9): 1072-1078, 2023 Sep 01.
Article in English | MEDLINE | ID: mdl-37597840

ABSTRACT

PURPOSE: The efficacy of isolated and relative performance indicators (PIs) has been compared in rugby union; the latter more effective at discerning match outcomes. However, this methodology has not been applied in women's rugby. The aim of this study was to identify PIs that maximize prediction accuracy of match outcome, from isolated and relative data sets, in women's rugby union. METHODS: Twenty-six PIs were selected from 110 women's international rugby matches between 2017 and 2022 to form an isolated data set, with relative data sets determined by subtracting corresponding opposition PIs. Random forest classification was completed on both data sets, and feature selection and importance were used to simplify models and interpret key PIs. Models were used in prediction on the 2021 World Cup to evaluate performance on unseen data. RESULTS: The isolated full model correctly classified 75% of outcomes (CI, 65%-82%), whereas the relative full model correctly classified 78% (CI, 69%-86%). Reduced respective models correctly classified 74% (CI, 65%-82%) and 76% (CI, 67%-84%). Reduced models correctly predicted 100% and 96% of outcomes for isolated and relative test data sets, respectively. No significant difference in accuracy was found between data sets. In the relative reduced model, meters made, clean breaks, missed tackles, lineouts lost, carries, and kicks from hand were significant. CONCLUSIONS: Increased relative meters made, clean breaks, carries, and kicks from hand and decreased relative missed tackles and lineouts lost were associated with success. This information can be utilized to inform physical and tactical preparation and direct physiological studies in women's rugby.


Subject(s)
Rugby , Upper Extremity , Humans , Female , Random Forest
4.
J Ren Care ; 49(1): 15-23, 2023 Mar.
Article in English | MEDLINE | ID: mdl-35226403

ABSTRACT

BACKGROUND: When people with chronic kidney disease reach kidney failure, renal replacement therapy is usually required to improve symptoms and maintain life. Although in-centre haemodialysis is most commonly used for this purpose, other forms of dialysis are available, including home haemodialysis and peritoneal dialysis. OBJECTIVES: We aimed to explore the experiences of adults living with chronic kidney disease who were either approaching the need for dialysis or had reached kidney failure and were receiving a form of dialysis. In particular, we explored how different forms of dialysis affect their quality of life, wellbeing, and physical activity. METHODS: Individual semistructured interviews were conducted with 40 adults with kidney failure, comprising four groups (n = 10 each): those receiving in-centre haemodialysis, home haemodialysis or peritoneal dialysis, or predialysis. Interviews were transcribed verbatim, thematically analysed, and then composite vignettes were subsequently developed to present a rich narrative of the collective experiences of each group. FINDINGS: Compared with adults who were predialysis, quality of life and wellbeing improved upon initiation of their home haemodialysis or peritoneal dialysis. Conversely, minimal improvement was perceived by those receiving in-centre haemodialysis. Low physical activity was reported across all four groups, although those receiving home haemodialysis and peritoneal dialysis reported a greater desire and ability to be physically active than those in-centre. CONCLUSION: These findings highlight that dialysis modalities not requiring regular hospital attendance (i.e., home haemodialysis and peritoneal dialysis) improve independence, quality of life, wellbeing, and can facilitate a more physically active lifestyle.


Subject(s)
Kidney Failure, Chronic , Peritoneal Dialysis , Renal Insufficiency, Chronic , Adult , Humans , Renal Dialysis , Quality of Life , Kidney Failure, Chronic/therapy , Renal Insufficiency, Chronic/therapy
5.
RMD Open ; 7(3)2021 10.
Article in English | MEDLINE | ID: mdl-34725262

ABSTRACT

OBJECTIVE: To update the EULAR 2020 systematic literature review (SLR) on efficacy and safety of immunomodulatory agents in SARS-CoV-2 infection. METHODS: As part of a EULAR taskforce, a systematic literature search update was conducted from 11 December 2020 to 14 July 2021. Two reviewers independently identified eligible studies and extracted data on efficacy and safety of immunomodulatory agents used therapeutically in SARS-CoV-2 infection at any stage of disease. The risk of bias (RoB) was assessed with validated tools. RESULTS: Of the 26 959 records, 520 articles were eligible for inclusion. Studies were mainly at high or unclear RoB. New randomised controlled trials (RCTs) on tocilizumab clarified its benefit in patients with severe and critical COVID-19, mainly if associated with glucocorticoids. There are emergent data on the usefulness of baricitinib and tofacitinib in severe COVID-19. Other therapeutic strategies such as the use of convalescent plasma and anti-SARS-CoV-2 monoclonal antibodies showed efficacy in subjects not mounting normal anti-SARS-CoV-2 antibody responses. CONCLUSION: This new SLR confirms that some immunomodulators (tocilizumab and JAK inhibitors) have a role for treating severe and critical COVID-19. Although better evidence is available compared with the previous SLR, the need of RCT with combination therapy (glucocorticoids+anti-cytokines) versus monotherapy with glucocorticoids still remains alongside the need for standardisation of inclusion criteria and outcomes to ultimately improve the care and prognosis of affected people. This SLR informed the 2021 update of the EULAR points to consider on the use of immunomodulatory therapies in COVID-19.


Subject(s)
COVID-19 , Immunotherapy , COVID-19/therapy , Humans , Immunization, Passive , COVID-19 Serotherapy
6.
Article in English | MEDLINE | ID: mdl-33803708

ABSTRACT

Early in the coronavirus-2019 (COVID-19) containment strategy, people with end-stage renal disease (ESRD) were identified as extremely clinically vulnerable and subsequently asked to 'shield' at home where possible. The aim of this study was to investigate how these restrictions and the transition to an increased reliance on telemedicine within clinical care of people living with kidney disease impacted the physical activity (PA), wellbeing and quality of life (QoL) of adults dialysing at home (HHD) or receiving in-centre haemodialysis (ICHD) in the UK. Individual semistructured telephone interviews were conducted with adults receiving HHD (n = 10) or ICHD (n = 10), were transcribed verbatim and, subsequently, thematically analysed. As result of the COVID-19 restrictions, PA, wellbeing and QoL of people with ESRD were found to have been hindered. However, widespread support for the continued use of telemedicine was strongly advocated and promoted independence and satisfaction in patient care. These findings highlight the need for more proactive care of people with ESRD if asked to shield again, as well as increased awareness of safe and appropriate PA resources to help with home-based PA and emotional wellbeing.


Subject(s)
COVID-19 , Coronavirus , Kidney Failure, Chronic , Telemedicine , Adult , Exercise , Humans , Kidney Failure, Chronic/therapy , Quality of Life , SARS-CoV-2 , United Kingdom
7.
RMD Open ; 7(1)2021 02.
Article in English | MEDLINE | ID: mdl-33574116

ABSTRACT

BACKGROUND: The SARS-CoV-2 pandemic is a global health problem. Beside the specific pathogenic effect of SARS-CoV-2, incompletely understood deleterious and aberrant host immune responses play critical roles in severe disease. Our objective was to summarise the available information on the pathophysiology of COVID-19. METHODS: Two reviewers independently identified eligible studies according to the following PICO framework: P (population): patients with SARS-CoV-2 infection; I (intervention): any intervention/no intervention; C (comparator): any comparator; O (outcome) any clinical or serological outcome including but not limited to immune cell phenotype and function and serum cytokine concentration. RESULTS: Of the 55 496 records yielded, 84 articles were eligible for inclusion according to question-specific research criteria. Proinflammatory cytokine expression, including interleukin-6 (IL-6), was increased, especially in severe COVID-19, although not as high as other states with severe systemic inflammation. The myeloid and lymphoid compartments were differentially affected by SARS-CoV-2 infection depending on disease phenotype. Failure to maintain high interferon (IFN) levels was characteristic of severe forms of COVID-19 and could be related to loss-of-function mutations in the IFN pathway and/or the presence of anti-IFN antibodies. Antibody response to SARS-CoV-2 infection showed a high variability across individuals and disease spectrum. Multiparametric algorithms showed variable diagnostic performances in predicting survival, hospitalisation, disease progression or severity, and mortality. CONCLUSIONS: SARS-CoV-2 infection affects both humoral and cellular immunity depending on both disease severity and individual parameters. This systematic literature review informed the EULAR 'points to consider' on COVID-19 pathophysiology and immunomodulatory therapies.


Subject(s)
COVID-19/epidemiology , COVID-19/physiopathology , Immunity, Cellular , Immunity, Humoral , Pandemics , SARS-CoV-2/genetics , Adult , COVID-19/immunology , COVID-19/virology , Child , Cytokines/metabolism , Extracellular Traps/immunology , Female , Humans , Lymphocytes/immunology , Male , Phenotype , Severity of Illness Index
8.
Ann Rheum Dis ; 80(6): 803-815, 2021 06.
Article in English | MEDLINE | ID: mdl-33589438

ABSTRACT

OBJECTIVE: To summarise the available information on efficacy and safety of immunomodulatory agents in SARS-CoV-2 infection. METHODS: As part of a European League Against Rheumatism (EULAR) taskforce, a systematic literature search was conducted from January 2019 to 11 December 2020. Two reviewers independently identified eligible studies according to the Population, Intervention, Comparator and Outcome framework and extracted data on efficacy and safety of immunomodulatory agents used therapeutically in SARS-CoV-2 infection at any stage. The risk of bias was assessed with validated tools. RESULTS: Of the 60 372 records, 401 articles were eligible for inclusion. Studies were at variable risk of bias. Randomised controlled trials (RCTs) were available for the following drugs: hydroxychloroquine (n=12), glucocorticoids (n=6), tocilizumab (n=4), convalescent plasma (n=4), interferon beta (n=2), intravenous immunoglobulins (IVIg) (n=2) and n=1 each for anakinra, baricitinib, colchicine, leflunomide, ruxolitinib, interferon kappa and vilobelimab. Glucocorticoids were able to reduce mortality in specific subsets of patients, while conflicting data were available about tocilizumab. Hydroxychloroquine was not beneficial at any disease stage, one RCT with anakinra was negative, one RCT with baricitinib+remdesivir was positive, and individual trials on some other compounds provided interesting, although preliminary, results. CONCLUSION: Although there is emerging evidence about immunomodulatory therapies for the management of COVID-19, conclusive data are scarce with some conflicting data. Since glucocorticoids seem to improve survival in some subsets of patients, RCTs comparing glucocorticoids alone versus glucocorticoids plus anticytokine/immunomodulatory treatment are warranted. This systematic literature review informed the initiative to formulate EULAR 'points to consider' on COVID-19 pathophysiology and immunomodulatory treatment from the rheumatology perspective.


Subject(s)
COVID-19 Drug Treatment , COVID-19 , Rheumatic Diseases , COVID-19/therapy , Glucocorticoids/therapeutic use , Humans , Hydroxychloroquine/therapeutic use , Immunization, Passive/methods , Interleukin 1 Receptor Antagonist Protein , SARS-CoV-2 , COVID-19 Serotherapy
9.
Bone Jt Open ; 1(12): 720-730, 2020 Dec 02.
Article in English | MEDLINE | ID: mdl-33367278

ABSTRACT

AIMS: Perthes' disease is a condition leading to necrosis of the femoral head. It is most common in children aged four to nine years, affecting around one per 1,200 children in the UK. Management typically includes non-surgical treatment options, such as physiotherapy with/without surgical intervention. However, there is significant variation in care with no consensus on the most effective treatment option. METHODS: This systematic review aims to evaluate the effectiveness of non-surgical interventions for the treatment of Perthes' disease. Comparative studies (experimental or observational) of any non-surgical intervention compared directly with any alternative intervention (surgical, non-surgical or no intervention) were identified from: Cochrane Central Register of Controlled Trials, MEDLINE, EMBASE, the Cumulative Index to Nursing and Allied Health Literature (CINAHL), EMcare, Allied and Complementary Medicine Database (AMED), and the Physiotherapy Evidence Database (PEDro). Data were extracted on interventions compared and methodological quality. For post-intervention primary outcome of radiological scores (Stulberg and/or Mose), event rates for poor scores were calculated with significance values. Secondary outcomes included functional measures, such as range of movement, and patient-reported outcomes such as health-related quality of life. RESULTS: In all, 15 studies (1,745 participants) were eligible for inclusion: eight prospective cohort studies, seven retrospective cohort studies, and no randomized controlled trials were identified. Non-surgical interventions largely focused on orthotic management (14/15 studies) and physical interventions such as muscle strengthening or stretching (5/15 studies). Most studies were of high/unknown risk of bias, and the range of patient outcomes was very limited, as was reporting of treatment protocols. Similar proportions of children achieving poor radiological outcomes were found for orthotic management and physical interventions, such as physiotherapy or weightbearing alteration, compared with surgical interventions or no intervention. CONCLUSION: Evidence from non-randomized studies found no robust evidence regarding the most effective non-surgical interventions for the treatment of children with Perthes' disease. Future research, employing randomized trial designs, and reporting a wider range of patient outcomes is urgently needed to inform clinical practice.Cite this article: Bone Jt Open 2020;1-12:720-730.

10.
NPJ Vaccines ; 5(1): 41, 2020.
Article in English | MEDLINE | ID: mdl-32435515

ABSTRACT

The main objective of the MACIVIVA European consortium was to develop new Good Manufacturing Practice pilot lines for manufacturing thermostable vaccines with stabilized antigens on influenza virosomes as enveloped virus-like particles. The HIV-1 gp41-derived antigens anchored in the virosome membrane, along with the adjuvant 3M-052 (TLR7/8 agonist) on the same particle, served as a candidate vaccine for the proof of concept for establishing manufacturing processes, which can be directly applied or adapted to other virosomal vaccines or lipid-based particles. Heat spray-dried powders suitable for nasal or oral delivery, and freeze-dried sublingual tablets were successfully developed as solid dosage forms for mucosal vaccination. The antigenic properties of vaccinal antigens with key gp41 epitopes were maintained, preserving the original immunogenicity of the starting liquid form, and also when solid forms were exposed to high temperature (40 °C) for up to 3 months, with minimal antigen and adjuvant content variation. Virosomes reconstituted from the powder forms remained as free particles with similar size, virosome uptake by antigen-presenting cells in vitro was comparable to virosomes from the liquid form, and the presence of excipients specific to each solid form did not prevent virosome transport to the draining lymph nodes of immunized mice. Virosome integrity was also preserved during exposure to <-15 °C, mimicking accidental freezing conditions. These "ready to use and all-in-one" thermostable needle-free virosomal HIV-1 mucosal vaccines offer the advantage of simplified logistics with a lower dependence on the cold chain during shipments and distribution.

11.
Rheumatol Adv Pract ; 4(2): rkaa032, 2020.
Article in English | MEDLINE | ID: mdl-33542971

ABSTRACT

BACKGROUND: Psoriatic disease (PsD) is a complex systemic disorder with cutaneous and musculoskeletal manifestations. Current evidence on pharmacological interventions, effective across the spectrum of clinical manifestations of early, systemic treatment-naïve PsD, is limited. This review aims to appraise such evidence. METHODS: This systematic review examined seven patient-intervention-comparator-outcome research questions to address the efficacy of the interventions on the following: across the spectrum of clinical manifestations PsD activity; peripheral arthritis; dactylitis; spondylitis; enthesitis; skin; and nails. Early PsD was defined as a disease duration of ≤2 years, except for studies investigating outcomes restricted to the skin. Eligible references were clinical trials or well-designed prospective studies/series reporting on adult humans, untreated, with cutaneous and/or musculoskeletal features of PsD. RESULTS: Nine references (out of 160 319, publication range 1946-2019) fulfilled the eligibility criteria. No study adopted comprehensive (that is, simultaneous assessment of different PsD manifestations) composite indices as primary outcome measures. Individual studies reported that apremilast and biologics successfully improved outcomes (disease activity index for PsA, minimal disease activity, PsA DAS, psoriasis area and severity index, PsA response criteria) when efficacy analyses were restricted to single manifestations of untreated PsD. Only qualitative synthesis of evidence was possible, owing to the following factors: data heterogeneity (disease classification criteria, outcome measures); unavailable data subsets (focused on early, untreated PsD) at the single study level; and insufficient data on the exposure of participants to previous treatment. CONCLUSION: Effective interventions, albeit limited in scope, were found for early, treatment-naïve PsD. No study provided evidence about the management of co-occurring cutaneous and musculoskeletal manifestations in early, treatment-naïve PsD. This review highlights an unmet need in research on early PsD.

12.
Pharm Res ; 34(5): 941-956, 2017 05.
Article in English | MEDLINE | ID: mdl-27633887

ABSTRACT

PURPOSE: Investigate the extended release behaviour of compacts containing mixtures of hydrophilic HPMC and PEO in hydrating media of differing ionic strengths. METHODS: The extended release behaviour of various HPMC:PEO compacts was investigated using dissolution testing, confocal microscopy and magnetic resonance imaging, with respect to polymer ratio and ionic strength of the hydrating media. RESULTS: Increasing HPMC content gave longer extended release times, but a greater sensitivity to high ionic dissolution environments. Increasing PEO content reduced this sensitivity. The addition of PEO to a predominantly HPMC matrix reduced release rate sensitivity to high ionic environments. Confocal microscopy of early gel layer development showed the two polymers appeared to contribute independently to gel layer structure whilst together forming a coherent and effective diffusion barrier. There was some evidence that poorly swollen HPMC particles added a tortuosity barrier to the gel layer in high ionic strength environments, resulting in prolonged extended release. MRI provides unique, non-invasive spatially resolved information from within the HPMC:PEO compacts that furthers our understanding of USP 1 and USP 4 dissolution data. CONCLUSIONS: Confocal microscopy and MRI data show that combinations of HPMC and PEO have advantageous extended release properties, in comparison with matrices containing a single polymer.


Subject(s)
Delayed-Action Preparations/chemistry , Hypromellose Derivatives/chemistry , Ions/chemistry , Polyethylene Glycols/chemistry , Hydrophobic and Hydrophilic Interactions , Osmolar Concentration , Polymers/chemistry , Sensitivity and Specificity , Solubility
13.
Int J Pharm ; 510(1): 210-20, 2016 Aug 20.
Article in English | MEDLINE | ID: mdl-27311354

ABSTRACT

The Dynamic Gastric Model (DGM) is an in-vitro system which aims to closely replicate the complex mixing, dynamic biochemical release and emptying patterns of the human stomach. In this study, the DGM was used to understand how the polymer content of hydrophilic matrices influences drug release in fasted and fed dissolution environments. Matrices containing a soluble model drug (caffeine) and between 10 and 30% HPMC 2208 (METHOCEL(®) K4M CR) were studied in the DGM under simulated fasted and fed conditions. The results were compared with compendial USP I and USP II dissolution tests. The USP I and II tests clearly discriminated between formulations containing different polymer levels, whereas the fasted DGM test bracketed drug release profiles into three groups and was not able to distinguish between some different formulations. DGM tests in the fed state showed that drug release was substantially influenced by the presence of a high fat meal. Under these conditions, there was a delay before initial drug release, and differences between matrices with different polymer contents were no longer clear. Matrices containing the typical amount of HPMC polymer (30% w/w) exhibited similar release rates under fed and fasted DGM conditions, but matrices with lower polymer contents exhibited more rapid drug release in the fasted state. In both the fasted and fed states erosion mechanisms appeared to dominate drug release in the DGM: most likely a consequence of the changing, cylindrical forces exerted during simulated antral cycling. This is in contrast to the USP tests in which diffusion played a significant role in the drug release process. This study is one of the first publications where a series of extended release (ER) formulations have been studied in the DGM. The technique appears to offer a useful tool to explore the potential sensitivity of ER formulations with respect to the gastric environment, especially the presence of food.


Subject(s)
Dietary Fats , Fasting , Gastric Emptying , Hydrophobic and Hydrophilic Interactions , Models, Biological , Polymers/chemistry , Chemistry, Pharmaceutical , Dietary Fats/administration & dosage , Polymers/analysis
14.
Eur J Pharm Biopharm ; 94: 485-92, 2015 Aug.
Article in English | MEDLINE | ID: mdl-26143369

ABSTRACT

Percolation theory has been used for several years in the design of HPMC hydrophilic matrices. This theory predicts that a minimum threshold content of polymer is required to provide extended release of drug, and that matrices with a lower polymer content will exhibit more rapid drug release as a result of percolation pathways facilitating the faster penetration of the aqueous medium. At present, percolation thresholds in HPMC matrices have been estimated solely through the mathematical modelling of dissolution data. This paper examines whether they can be also identified in a novel way: through the use of confocal laser scanning fluorescence microscopy (CLSM) to observe the morphology of the emerging gel layer during the initial period of polymer hydration and early gel formation at the matrix surface. In this study, matrices have been prepared with a polymer content of 5-30% w/w HPMC 2208 (Methocel K4M), with a mix of other excipients (a soluble drug (caffeine), lactose, microcrystalline cellulose and magnesium stearate) to provide a typical industrially realistic formulation. Dissolution studies, undertaken in water using USP apparatus 2 (paddle) at 50rpm, provided data for the calculation of the percolation threshold through relating dissolution kinetic parameters to the excipient volumetric fraction of the dry matrix. The HPMC percolation threshold estimated this way was found to be 12.8% v/v, which was equivalent to a matrix polymer content of 11.5% w/w. The pattern of polymer hydration and gel layer growth during early gel layer formation was examined by confocal laser scanning fluorescence microscopy (CLSM). Clear differences in gel layer formation were observed. At polymer contents above the estimated threshold a continuous gel layer was formed within 15min, whereas matrices with polymer contents below the threshold were characterised by irregular gel layer formation with little evidence of HPMC particle coalescence. According to percolation theory, this implies that a continuous cluster of HPMC particles was not formed. The images provide the first direct evidence of how the percolation threshold may be related to the success or failure of early gel layer development in HPMC matrices. It also shows how extended release characteristics are founded on the successful coalescence of hydrated polymer particles to form a continuous coherent diffusion barrier, which can then inhibit further percolation of the hydration medium. The correlation between percolation thresholds estimated from dissolution and imaging techniques suggests that confocal imaging may provide a more rapid method for estimating the percolation thresholds, facilitating the rational design of HPMC extended release matrices at lower polymer contents with minimal risk of dose dumping.


Subject(s)
Delayed-Action Preparations , Excipients/chemistry , Gels/chemistry , Hypromellose Derivatives/chemistry , Microscopy, Confocal/methods , Chemistry, Pharmaceutical , Drug Liberation , Kinetics , Solubility , Tablets
15.
Lancet ; 385(9975): 1305-14, 2015 Apr 04.
Article in English | MEDLINE | ID: mdl-25529582

ABSTRACT

BACKGROUND: Human genome sequencing has transformed our understanding of genomic variation and its relevance to health and disease, and is now starting to enter clinical practice for the diagnosis of rare diseases. The question of whether and how some categories of genomic findings should be shared with individual research participants is currently a topic of international debate, and development of robust analytical workflows to identify and communicate clinically relevant variants is paramount. METHODS: The Deciphering Developmental Disorders (DDD) study has developed a UK-wide patient recruitment network involving over 180 clinicians across all 24 regional genetics services, and has performed genome-wide microarray and whole exome sequencing on children with undiagnosed developmental disorders and their parents. After data analysis, pertinent genomic variants were returned to individual research participants via their local clinical genetics team. FINDINGS: Around 80,000 genomic variants were identified from exome sequencing and microarray analysis in each individual, of which on average 400 were rare and predicted to be protein altering. By focusing only on de novo and segregating variants in known developmental disorder genes, we achieved a diagnostic yield of 27% among 1133 previously investigated yet undiagnosed children with developmental disorders, whilst minimising incidental findings. In families with developmentally normal parents, whole exome sequencing of the child and both parents resulted in a 10-fold reduction in the number of potential causal variants that needed clinical evaluation compared to sequencing only the child. Most diagnostic variants identified in known genes were novel and not present in current databases of known disease variation. INTERPRETATION: Implementation of a robust translational genomics workflow is achievable within a large-scale rare disease research study to allow feedback of potentially diagnostic findings to clinicians and research participants. Systematic recording of relevant clinical data, curation of a gene-phenotype knowledge base, and development of clinical decision support software are needed in addition to automated exclusion of almost all variants, which is crucial for scalable prioritisation and review of possible diagnostic variants. However, the resource requirements of development and maintenance of a clinical reporting system within a research setting are substantial. FUNDING: Health Innovation Challenge Fund, a parallel funding partnership between the Wellcome Trust and the UK Department of Health.


Subject(s)
Developmental Disabilities/diagnosis , Genome, Human/genetics , Adolescent , Child , Child, Preschool , Developmental Disabilities/genetics , Female , Genetic Variation/genetics , Genome-Wide Association Study/methods , Heterozygote , Humans , Incidental Findings , Infant , Infant, Newborn , Information Dissemination , Male , Phenotype , Specimen Handling
16.
J Invasive Cardiol ; 22(3): 119-24, 2010 Mar.
Article in English | MEDLINE | ID: mdl-20197579

ABSTRACT

OBJECTIVES: To compare our experience with sirolimus and paclitaxel-eluting stents (drug-eluting stents [DES]) and non-drug-eluting stents (NDES) for treatment of vertebral artery (VA) origin stenosis and review the literature. METHODS: A retrospective review of our prospectively collected database was performed. Clinical and radiologic follow up was obtained by reviewing office records and radiology. Data collected included demographics, comorbidities, presenting symptoms, stenosis severity, contralateral VA stenosis and/or carotid stenosis, type of stent used, angioplasty before or after stenting, post-treatment residual stenosis, clinical and radiological follow up and retreatment. Patients with symptomatic > 60% stenosis or asymptomatic > 70% stenosis and/or a hypoplastic or occluded contralateral VA or significant carotid occlusion were chosen for revascularization. RESULTS: Thirty-five patients treated with NDES and 15 treated with DES for management of VA origin stenosis were identified. The technical success rate of the procedure was 100%. There were no procedural complications. There were 7 asymptomatic patients (NDES Group-4, DES Group-3). In the NDES Group, 9 patients had pre-stent angioplasty; 2 had post-stent angioplasty. In the DES group, 4 patients had post-stent angioplasty. Symptoms resolved in 30/31 (96.8%) patients treated with NDES and 11/12 (91.7%) treated with DES. Thirty-six patients had radiologic follow up (median 21.3 months); in-stent restenosis was documented in 11 patients (NDES 9/24 [38%], DES 2/12 [17%]). Among patients receiving NDES, re-stenotic lesions required angioplasty in 7 patients. No patients in the DES group required angioplasty. CONCLUSIONS: DES for treatment of VA origin stenosis may decrease the incidence of restenosis when compared to NDES. Validation in prospective, randomized, multicenter trials is necessary.


Subject(s)
Angioplasty, Balloon/methods , Drug-Eluting Stents , Stents , Vertebrobasilar Insufficiency/prevention & control , Vertebrobasilar Insufficiency/therapy , Adult , Aged , Aged, 80 and over , Angioplasty, Balloon/instrumentation , Female , Follow-Up Studies , Humans , Male , Middle Aged , Paclitaxel , Retrospective Studies , Secondary Prevention , Sirolimus , Treatment Outcome
17.
Oxid Med Cell Longev ; 2(4): 247-54, 2009.
Article in English | MEDLINE | ID: mdl-20716911

ABSTRACT

Many degenerative diseases are associated with increased oxidative stress. Creatine has the potential to act as an indirect and direct antioxidant; however, limited data exist to evaluate the antioxidant capabilities of creatine supplementation within in-vivo human systems. This study aimed to investigate the effects of oral creatine supplementation on markers of oxidative stress and antioxidant defenses following exhaustive cycling exercise. Following preliminary testing and two additional familiarization sessions, 18 active males repeated two exhaustive incremental cycling trials (T1 and T2) separated by exactly 7 days. The subjects were assigned, in a double-blind manner, to receive either 20 g of creatine (Cr) or a placebo (P) for the 5 days preceding T2. Breath-by-breath respiratory data and heart rate were continually recorded throughout the exercise protocol and blood samples were obtained at rest (preexercise), at the end of exercise (postexercise), and the day following exercise (post24 h). Serum hypdroperoxide concentrations were elevated at postexercise by 17 +/- 5% above pre-exercise values (P = 0.030). However, supplementation did not influence lipid peroxidation (serum hypdroperoxide concentrations), resistance of low density lipoprotein to oxidative stress (t1/2max LDL oxidation) and plasma concentrations of non-enzymatic antioxidants (retinol, alpha-carotene, beta-carotene, alpha-tocopherol, gamma-tocopherol, lycopene, and vitamin C). Heart rate and oxygen uptake responses to exercise were not affected by supplementation. These findings suggest that short-term creatine supplementation does not enhance non-enzymatic antioxidant defence or protect against lipid peroxidation induced by exhaustive cycling in healthy males.


Subject(s)
Creatine/pharmacology , Exercise , Oxidative Stress , Administration, Oral , Ascorbic Acid/blood , Carotenoids/blood , Creatine/physiology , Double-Blind Method , Heart Rate/drug effects , Humans , Lipid Peroxidation/drug effects , Lycopene , Male , Oxygen Consumption/drug effects , Tocopherols/blood , Vitamin A/blood , Young Adult
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