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1.
Cell ; 184(3): 827-839.e14, 2021 02 04.
Article in English | MEDLINE | ID: mdl-33545036

ABSTRACT

Ahmed and colleagues recently described a novel hybrid lymphocyte expressing both a B and T cell receptor, termed double expresser (DE) cells. DE cells in blood of type 1 diabetes (T1D) subjects were present at increased numbers and enriched for a public B cell clonotype. Here, we attempted to reproduce these findings. While we could identify DE cells by flow cytometry, we found no association between DE cell frequency and T1D status. We were unable to identify the reported public B cell clone, or any similar clone, in bulk B cells or sorted DE cells from T1D subjects or controls. We also did not observe increased usage of the public clone VH or DH genes in B cells or in sorted DE cells. Taken together, our findings suggest that DE cells and their alleged public clonotype are not enriched in T1D. This Matters Arising paper is in response to Ahmed et al. (2019), published in Cell. See also the response by Ahmed et al. (2021), published in this issue.


Subject(s)
Diabetes Mellitus, Type 1 , B-Lymphocytes , Clone Cells , Diabetes Mellitus, Type 1/genetics , Flow Cytometry , Humans , Receptors, Antigen, T-Cell
2.
JAMA ; 331(18): 1576-1585, 2024 05 14.
Article in English | MEDLINE | ID: mdl-38619828

ABSTRACT

Importance: Delayed diagnosis of a dislocated hip in infants can lead to complex childhood surgery, interruption to family life, and premature osteoarthritis. Objective: To evaluate the diagnostic accuracy of clinical examination in identifying dislocated hips in infants. Data Sources: Systematic search of CINAHL, Embase, MEDLINE, and the Cochrane Library from the inception of each database until October 31, 2023. Study Selection: The 9 included studies reported the diagnostic accuracy of the clinical examination (index test) in infants aged 3 months or younger and a diagnostic hip ultrasound (reference test). The Graf method of ultrasound assessment was used to classify hip abnormalities. Data Extraction and Synthesis: The Rational Clinical Examination scale was used to assign levels of evidence and the Quality Assessment of Diagnostic Accuracy Studies tool was used to assess bias. Data were extracted using the individual hip as the unit of analysis; the data were pooled when the clinical examinations were evaluated by 3 or more of the included studies. Main Outcomes and Measures: Sensitivity, specificity, and likelihood ratios (LRs) of identifying a dislocated hip were calculated. Results: Among infants screened with a clinical examination and a diagnostic ultrasound in 5 studies, the prevalence of a dislocated hip (n = 37 859 hips) was 0.94% (95% CI, 0.28%-2.0%). There were 8 studies (n = 44 827 hips) that evaluated use of the Barlow maneuver and the Ortolani maneuver (dislocate and relocate an unstable hip); the maneuvers had a sensitivity of 46% (95% CI, 26%-67%), a specificity of 99.1% (95% CI, 97.9%-99.6%), a positive LR of 52 (95% CI, 21-127), and a negative LR of 0.55 (95% CI, 0.37-0.82). There were 3 studies (n = 22 472 hips) that evaluated limited hip abduction and had a sensitivity of 13% (95% CI, 3.3%-37%), a specificity of 97% (95% CI, 87%-99%), a positive LR of 3.6 (95% CI, 0.72-18), and a negative LR of 0.91 (95% CI, 0.76-1.1). One study (n = 13 096 hips) evaluated a clicking sound and had a sensitivity of 13% (95% CI, 6.4%-21%), a specificity of 92% (95% CI, 92%-93%), a positive LR of 1.6 (95% CI, 0.91-2.8), and a negative LR of 0.95 (95% CI, 0.88-1.0). Conclusions and Relevance: In studies in which all infant hips were screened for developmental dysplasia of the hip, the prevalence of a dislocated hip was 0.94%. A positive LR for the Barlow and Ortolani maneuvers was the finding most associated with an increased likelihood of a dislocated hip. Limited hip abduction or a clicking sound had no clear diagnostic utility.


Subject(s)
Delayed Diagnosis , Hip Dislocation, Congenital , Female , Humans , Infant , Male , Delayed Diagnosis/adverse effects , Hip Dislocation, Congenital/classification , Hip Dislocation, Congenital/diagnosis , Hip Dislocation, Congenital/diagnostic imaging , Hip Dislocation, Congenital/epidemiology , Hip Joint/abnormalities , Hip Joint/diagnostic imaging , Physical Examination , Sensitivity and Specificity , Ultrasonography , Reproducibility of Results , Infant, Newborn , Prevalence
3.
Diabetologia ; 66(1): 127-131, 2023 01.
Article in English | MEDLINE | ID: mdl-36282337

ABSTRACT

AIMS/HYPOTHESIS: TCF7L2 variants are the strongest genetic risk factor for type 2 diabetes. In individuals with type 1 diabetes, these variants are associated with a higher C-peptide AUC, a lower glucose AUC during an OGTT, single autoantibody positivity near diagnosis, particularly in individuals older than 12 years of age, and a lower frequency of type 1 diabetes-associated HLA genotypes. Based on initial observations from clinical cohorts, we tested the hypothesis that type 2 diabetes-predisposing TCF7L2 genetic variants are associated with a higher percentage of residual insulin-containing cells (ICI%) in pancreases of donors with type 1 diabetes, by examining genomic data and pancreatic tissue samples from the Network for Pancreatic Organ donors with Diabetes (nPOD) programme. METHODS: We analysed nPOD donors with type 1 diabetes (n=110; mean±SD age at type 1 diabetes onset 12.2±7.9 years, mean±SD diabetes duration 15.3±13.7 years, 53% male, 80% non-Hispanic White, 12.7% African American, 7.3% Hispanic) using data pertaining to residual beta cell number; quantified islets containing insulin-positive beta cells in pancreatic tissue sections; and expressed these values as a percentage of the total number of islets from each donor (mean ± SD ICI% 9.8±21.5, range 0-92.2). RESULTS: Donors with a high ICI% (≥5) (n=30; 27%) vs a low ICI% (<5) (n=80; 73%) were older at onset (15.3±6.9 vs 11.1±8 years, p=0.013), had a shorter diabetes duration at donor tissue procurement (7.0±7.4 vs 18.5±14.3 years, p<0.001), a higher African ancestry score (0.2±0.3 vs 0.1±0.2, p=0.043) and a lower European ancestry score (0.7±0.3 vs 0.9±0.3, p=0.023). After adjustment for age of onset (p=0.105), diabetes duration (p<0.001), BMI z score (p=0.145), sex (p=0.351) and African American race (p=0.053), donors with the TCF7L2 rs7903146 T allele (TC or TT, 45.5%) were 2.93 times (95% CI 1.02, 8.47) more likely to have a high ICI% than those without it (CC) (p=0.047). CONCLUSIONS/INTERPRETATION: Overall, these data support the presence of a type 1 diabetes endotype associated with a genetic factor that predisposes to type 2 diabetes, with donors in this category exhibiting less severe beta cell loss. It is possible that in these individuals the disease pathogenesis may include mechanisms associated with type 2 diabetes and thus this may provide an explanation for the poor response to immunotherapies to prevent type 1 diabetes or its progression in a subset of individuals. If so, strategies that target both type 1 diabetes and type 2 diabetes-associated factors when they are present may increase the success of prevention and treatment in these individuals.


Subject(s)
Diabetes Mellitus, Type 1 , Diabetes Mellitus, Type 2 , Male , Humans , Child, Preschool , Child , Adolescent , Young Adult , Adult , Female , Insulin , Diabetes Mellitus, Type 1/genetics , Diabetes Mellitus, Type 2/genetics , Transcription Factor 7-Like 2 Protein/genetics
4.
Lancet ; 400(10345): 39-47, 2022 07 02.
Article in English | MEDLINE | ID: mdl-35780790

ABSTRACT

BACKGROUND: The most common fractures in children are torus (buckle) fractures of the wrist. Controversy exists over treatment, which ranges from splint immobilisation and discharge to cast immobilisation, follow-up, and repeat imaging. This study compared pain and function in affected children offered a soft bandage and immediate discharge with those receiving rigid immobilisation and follow-up as per treating centre protocol. METHODS: In this randomised controlled equivalence trial we included 965 children (aged 4-15 years) with a distal radius torus fracture from 23 hospitals in the UK. Children were randomly allocated in a 1:1 ratio to the offer of bandage group or rigid immobilisation group using bespoke web-based randomisation software. Treating clinicians, participants, and their families could not be masked to treatment allocation. Exclusion criteria included multiple injuries, diagnosis at more than 36 h after injury, and inability to complete follow-up. The primary outcome was pain at 3-days post-randomisation measured using Wong-Baker FACES Pain Rating Scale. We performed a modified intention-to-treat and per protocol analysis. The trial was registered with ISRCTN registry, ISRCTN13955395. FINDINGS: Between Jan 16, 2019, and July 13, 2020, 965 children were randomly allocated to a group, 489 to the offer of a bandage group and 476 to the rigid immobilisation group, 379 (39%) were girls and 586 (61%) were boys. Primary outcome data was collected for 908 (94%) of participants, all of whom were included in the modified intention-to-treat analysis. Pain was equivalent at 3 days with 3·21 points (SD 2·08) in the offer of bandage group versus 3·14 points (2·11) in the rigid immobilisation group. With reference to a prespecified equivalence margin of 1·0, the adjusted difference in the intention-to-treat population was -0·10 (95% CI -0·37 to 0·17) and-0·06 (95% CI -0·34 to 0·21) in the per-protocol population. INTERPRETATION: This trial found equivalence in pain at 3 days in children with a torus fracture of the distal radius assigned to the offer of a bandage group or the rigid immobilisation group, with no between-group differences in pain or function during the 6 weeks of follow-up. FUNDING: UK National Institute for Health and Care Research.


Subject(s)
Fractures, Bone , Wrist , Child , Female , Fractures, Bone/therapy , Humans , Male , Pain , United Kingdom , Wrist Joint
5.
Eur J Immunol ; 52(3): 372-388, 2022 03.
Article in English | MEDLINE | ID: mdl-35025103

ABSTRACT

Cytometric immunophenotyping is a powerful tool to discover and implement T-cell biomarkers of type 1 diabetes (T1D) progression and response to clinical therapy. Although many discovery-based T-cell biomarkers have been described, to date, no such markers have been widely adopted in standard practice. The heterogeneous nature of T1D and lack of standardized assays and experimental design across studies is a major barrier to the broader adoption of T-cell immunophenotyping assays. There is an unmet need to harmonize the design of immunophenotyping assays, including those that measure antigen-agnostic cell populations, such that data collected from different clinical trial sites and T1D cohorts are comparable, yet account for cohort-specific features and different drug mechanisms of action. In these Guidelines, we aim to provide expert advice on how to unify aspects of study design and practice. We provide recommendations for defining cohorts, method implementation, as well as tools for data analysis and reporting by highlighting and building on selected successes. Harmonization of cytometry-based T-cell assays will allow researchers to better integrate findings across trials, ultimately enabling the identification and validation of biomarkers of disease progression and treatment response in T1D.


Subject(s)
Diabetes Mellitus, Type 1 , Biomarkers/analysis , Diabetes Mellitus, Type 1/diagnosis , Diabetes Mellitus, Type 1/therapy , Flow Cytometry/methods , Humans , Immunophenotyping , T-Lymphocytes
6.
BMC Med ; 21(1): 244, 2023 07 04.
Article in English | MEDLINE | ID: mdl-37403173

ABSTRACT

BACKGROUND: Randomised controlled trials are often beset by problems with poor recruitment and retention. Information to support decisions on trial participation is usually provided as printed participant information sheets (PIS), which are often long, technical, and unappealing. Multimedia information (MMI), including animations and videos, may be a valuable alternative or complement to a PIS. The Trials Engagement in Children and Adolescents (TRECA) study compared MMI to PIS to investigate the effects on participant recruitment, retention, and quality of decision-making. METHODS: We undertook six SWATs (Study Within A Trial) within a series of host trials recruiting children and young people. Potential participants in the host trials were randomly allocated to receive MMI-only, PIS-only, or combined MMI + PIS. We recorded the rates of recruitment and retention (varying between 6 and 26 weeks post-randomisation) in each host trial. Potential participants approached about each host trial were asked to complete a nine-item Decision-Making Questionnaire (DMQ) to indicate their evaluation of the information and their reasons for participation/non-participation. Odds ratios were calculated and combined in a meta-analysis. RESULTS: Data from 3/6 SWATs for which it was possible were combined in a meta-analysis (n = 1758). Potential participants allocated to MMI-only were more likely to be recruited to the host trial than those allocated to PIS-only (OR 1.54; 95% CI 1.05, 2.28; p = 0.03). Those allocated to combined MMI + PIS compared to PIS-only were no more likely to be recruited to the host trial (OR = 0.89; 95% CI 0.53, 1.50; p = 0.67). Providing MMI rather than PIS did not impact on DMQ scores. Once children and young people had been recruited to host trials, their trial retention rates did not differ according to intervention allocation. CONCLUSIONS: Providing MMI-only increased the trial recruitment rate compared to PIS-only but did not affect DMQ scores. Combined MMI + PIS instead of PIS had no effect on recruitment or retention. MMIs are a useful tool for trial recruitment in children and young people, and they could reduce trial recruitment periods.


Subject(s)
Multimedia , Adolescent , Humans , Child , Patient Selection , Surveys and Questionnaires , Randomized Controlled Trials as Topic
7.
J Immunol ; 207(3): 849-859, 2021 08 01.
Article in English | MEDLINE | ID: mdl-34301848

ABSTRACT

A missense mutation (R620W) of protein tyrosine phosphatase nonreceptor type 22 (PTPN22), which encodes lymphoid-tyrosine phosphatase (LYP), confers genetic risk for multiple autoimmune diseases including type 1 diabetes. LYP has been putatively demonstrated to attenuate proximal T and BCR signaling. However, limited data exist regarding PTPN22 expression within primary T cell subsets and the impact of the type 1 diabetes risk variant on human T cell activity. In this study, we demonstrate endogenous PTPN22 is differentially expressed and dynamically controlled following activation. From control subjects homozygous for the nonrisk allele, we observed 2.1- (p < 0.05) and 3.6-fold (p < 0.001) more PTPN22 transcripts in resting CD4+ memory and regulatory T cells (Tregs), respectively, over naive CD4+ T cells, with expression peaking 24 h postactivation. When LYP was overexpressed in conventional CD4+ T cells, TCR signaling and activation were blunted by LYP-620R (p < 0.001) but only modestly affected by the LYP-620W risk variant versus mock-transfected control, with similar results observed in Tregs. LYP overexpression only impacted proliferation following activation by APCs but not anti-CD3- and anti-CD28-coated microbeads, suggesting LYP modulation of pathways other than TCR. Notably, proliferation was significantly lower with LYP-620R than with LYP-620W overexpression in conventional CD4+ T cells but was similar in Treg. These data indicate that the LYP-620W variant is hypomorphic in the context of human CD4+ T cell activation and may have important implications for therapies seeking to restore immunological tolerance in autoimmune disorders.


Subject(s)
Protein Tyrosine Phosphatase, Non-Receptor Type 22/metabolism , Signaling Lymphocytic Activation Molecule Associated Protein/metabolism , T-Lymphocyte Subsets/immunology , T-Lymphocytes, Regulatory/immunology , Autoimmunity , Cell Differentiation , Cell Proliferation , Cells, Cultured , Gene Expression Regulation , Genetic Variation , Humans , Immune Tolerance , Immunologic Memory , Lymphocyte Activation/genetics , Mutation/genetics , Protein Tyrosine Phosphatase, Non-Receptor Type 22/genetics , Signaling Lymphocytic Activation Molecule Associated Protein/genetics
8.
Ann Surg ; 275(3): 506-514, 2022 03 01.
Article in English | MEDLINE | ID: mdl-33491982

ABSTRACT

OBJECTIVE: The objective of this study was to evaluate England's Best Practice Tariff (BPT) and consider potential implications for Medicare patients should the US adopt a similar plan. SUMMARY BACKGROUND DATA: Since the beginning of the Affordable Care Act, Medicare has renewed efforts to improve the outcomes of older adults through introduction of an expanding set of alternative-payment models. Among trauma patients, recommended arrangements met with mixed success given concerns about the heterogeneous nature of trauma patients and resulting outcome variation. A novel approach taken for hip fractures in England could offer a viable alternative. METHODS: Linear regression, interrupted time-series, difference-in-difference, and counterfactual models of 2000 to 2016 Medicare (US), HES-APC (England) death certificate-linked claims (≥65 years) were used to: track US hip fracture trends, look at changes in English hip fracture trends before-and-after BPT implementation, compare changes in US-versus-English mortality, and estimate total/theoretical lives saved. RESULTS: A total of 806,036 English and 3,221,109 US hospitalizations were included. After BPT implementation, England's 30-day mortality decreased by 2.6 percentage-points (95%CI: 1.7-3.5) from a baseline of 9.9% (relative reduction 26.3%). 90- and 365-day mortality decreased by 5.6 and 5.4 percentage-points. 30/90/365-day readmissions also declined with a concurrent shortening of hospital length-of-stay. From 2000 to 2016, US outcomes were stagnant (P > 0.05), resulting in an inversion of the countries' mortality and >38,000 potential annual US lives saved. CONCLUSIONS: Process measure pay-for-performance led to significant improvements in English hip fracture outcomes. As efforts to improve US older adult health continue to increase, there are important lessons to be learned from a successful initiative like the BPT.


Subject(s)
Hip Fractures/surgery , Medicare , Process Assessment, Health Care , Reimbursement, Incentive , Aged , Aged, 80 and over , Benchmarking , England , Female , Humans , Male , Treatment Outcome , United States
9.
Mol Ther ; 29(9): 2660-2676, 2021 09 01.
Article in English | MEDLINE | ID: mdl-33940160

ABSTRACT

Regulatory T cells (Tregs) control immune responses in autoimmune disease, transplantation, and enable antigen-specific tolerance induction in protein-replacement therapies. Tregs can exert a broad array of suppressive functions through their T cell receptor (TCR) in a tissue-directed and antigen-specific manner. This capacity can now be harnessed for tolerance induction by "redirecting" polyclonal Tregs to overcome low inherent precursor frequencies and simultaneously augment suppressive functions. With the use of hemophilia A as a model, we sought to engineer antigen-specific Tregs to suppress antibody formation against the soluble therapeutic protein factor (F)VIII in a major histocompatibility complex (MHC)-independent fashion. Surprisingly, high-affinity chimeric antigen receptor (CAR)-Treg engagement induced a robust effector phenotype that was distinct from the activation signature observed for endogenous thymic Tregs, which resulted in the loss of suppressive activity. Targeted mutations in the CD3ζ or CD28 signaling motifs or interleukin (IL)-10 overexpression were not sufficient to restore tolerance. In contrast, complexing TCR-based signaling with single-chain variable fragment (scFv) recognition to generate TCR fusion construct (TRuC)-Tregs delivered controlled antigen-specific signaling via engagement of the entire TCR complex, thereby directing functional suppression of the FVIII-specific antibody response. These data suggest that cellular therapies employing engineered receptor Tregs will require regulation of activation thresholds to maintain optimal suppressive function.


Subject(s)
Factor VIII/immunology , Hemophilia A/therapy , Mutation , Receptors, Chimeric Antigen/metabolism , T-Lymphocytes, Regulatory/immunology , Adaptive Immunity , Animals , CD28 Antigens/genetics , CD3 Complex/genetics , Disease Models, Animal , Hemophilia A/genetics , Hemophilia A/immunology , Humans , Interleukin-10/genetics , Male , Mice
10.
Cochrane Database Syst Rev ; 10: CD012717, 2022 10 10.
Article in English | MEDLINE | ID: mdl-36214650

ABSTRACT

BACKGROUND: Developmental dysplasia of the hip (DDH) describes the abnormal development of a hip in childhood, ranging from complete dislocation of the hip joint to subtle immaturity of a hip that is enlocated and stable within the socket. DDH occurs in around 10 per 1000 live births, though only one per 1000 are completely dislocated. There is variation in treatment pathways for DDH, which differs between hospitals and even between clinicians within the same hospital. The variation is related to the severity of dysplasia that is believed to require treatment, and the techniques used to treat dysplasia. OBJECTIVES: To determine the effectiveness of splinting and the optimal treatment strategy for the non-operative management of DDH in babies under six months of age. SEARCH METHODS: We searched CENTRAL, MEDLINE, Embase, seven other electronic databases, and two trials registers up to November 2021. We also checked reference lists, contacted study authors, and handsearched relevant meetings abstracts. SELECTION CRITERIA: Randomised controlled trials (RCTs), including quasi-RCTs, as well as non-RCTs and cohort studies conducted after 1980 were included. Participants were babies with all severities of DDH who were under six months of age. Interventions included dynamic splints, static splints or double nappies (diapers), compared to no splinting or delayed splinting. DATA COLLECTION AND ANALYSIS: Two review authors independently selected studies, extracted data and performed risk of bias and GRADE assessments. The primary outcomes were: measurement of acetabular index at years one, two and five, as determined by radiographs (angle): the need for operative intervention to achieve reduction and to address dysplasia; and complications. We also investigated other outcomes highlighted by parents as important, including the bond between parent and child and the ability of mothers to breastfeed. MAIN RESULTS: We included six RCTs or quasi-RCTs (576 babies). These were supported by 16 non-RCTs (8237 babies). Five studies had non-commercial funding, three studies stated 'no funding' and 14 studies did not state funding source. The RCTs were generally at unclear risk of bias, although we judged three RCTs to be at high risk of bias for incomplete outcome data. The non-RCTs were of moderate and critical risk of bias. We did not undertake meta-analysis due to methodological and clinical differences between studies; instead, we have summarised the results narratively. Dynamic splinting versus delayed or no splinting Four RCTs and nine non-RCTs compared immediate dynamic splinting and delayed dynamic splinting or no splinting. Of the RCTs, two considered stable hips and one considered unstable (dislocatable) hips and one jointly considered unstable and stable hips. No studies considered only dislocated hips. Two RCTs (265 babies, very low-certainty evidence) reported acetabular index at one year amongst stable or dislocatable hips. Both studies found there may be no evidence of a difference in splinting stable hips at first diagnosis compared to a strategy of active surveillance: one reported a mean difference (MD) of 0.10 (95% confidence interval (CI) -0.74 to 0.94), and the other an MD of 0.20 (95% CI -1.65 to 2.05). Two RCTs of stable hips (181 babies, very low-certainty evidence) reported there may be no evidence of a difference between groups for acetabular index at two years: one study reported an MD of -1.90 (95% CI -4.76 to 0.96), and another study reported an MD of -0.10 (95% CI -1.93 to 1.73), but did not take into account hips from the same child. No study reported data at five years. Four RCTs (434 babies, very low-certainty evidence) reported the need for surgical intervention. Three studies reported that no surgical interventions occurred. In the remaining study, two babies in the dynamic splinting group developed instability and were subsequently treated surgically. This study did not explicitly state if this treatment was to achieve concentric reduction or address residual dysplasia. Three RCTs (390 babies, very low-certainty evidence) reported no complications (avascular necrosis and femoral nerve palsy). Dynamic splinting versus static splinting One RCT and five non-RCTs compared dynamic versus static splinting. The RCT (118 hips) reported no occurrences of avascular necrosis (very low-certainty evidence) and did not report radiological outcomes or need for operative intervention. One quasi-RCT compared double nappies versus delayed or no splinting but reported no outcomes of interest. Other comparisons No RCTs compared static splinting versus delayed or no splinting or staged weaning versus immediate removal. AUTHORS' CONCLUSIONS: There is a paucity of RCT evidence for splinting for the non-operative management of DDH: we included only six RCTs with 576 babies. Moreover, there was considerable heterogeneity between the studies, precluding meta-analysis. We judged the RCT evidence for all primary outcomes as being of very low certainty, meaning we are very uncertain about the true effects. Results from individual studies provide limited evidence of intervention effects on different severities of DDH. Amongst stable dysplastic hips, there was no evidence to suggest that treatment at any stage expedited the development of the acetabulum. For dislocatable hips, a delay in treatment onset to six weeks does not appear to result in any evidence of a difference in the development of the acetabulum at one year or increased risk of surgery. However, delayed splinting may reduce the number of babies requiring treatment with a harness. No RCTs compared static splinting with delayed or no splinting, staged weaning versus immediate removal or double nappies versus delayed or no splinting. There were few operative interventions or complications amongst the RCTs and the non-randomised studies. There's no apparent signal to indicate a higher frequency of either outcome in either intervention group. Given the frequency of this disease, and the fact that many countries undertake mandatory DDH screening, there is a clear need to develop an evidence-based pathway for treatment. Particular uncertainties requiring future research are the effectiveness of splinting amongst stable dysplastic hips, the optimal timing for the onset of splinting, the optimal type of splint to use and the need for 'weaning of splints'. Only once a robust pathway for treatment is established, can we properly assess the cost-effectiveness of screening interventions for DDH.


Subject(s)
Developmental Dysplasia of the Hip , Bias , Child , Female , Humans , Infant , Mothers , Necrosis , Parents
11.
Microsc Microanal ; : 1-8, 2022 Mar 22.
Article in English | MEDLINE | ID: mdl-35315316

ABSTRACT

Indium (In) and other low melting point metals are used as interconnects in a variety of hybridized circuits and a full understanding of the metallurgy of these interconnects is important to the reliability and performance of the devices. This paper shows that room temperature focused ion beam (FIB) preparation of cross-sections, using Ga+ or Xe+ can result in artifacts that obscure the true In microbump structure. The use of modified milling strategies to minimize the increased local sample temperature are shown to produce cross-sections that are representative of the In bump microstructure in some sample configurations. Furthermore, cooling of the sample to cryogenic temperatures is shown to reliably eliminate artifacts in FIB prepared cross-sections of In bumps allowing the true bump microstructure to be observed.

12.
Immunol Cell Biol ; 99(5): 496-508, 2021 05.
Article in English | MEDLINE | ID: mdl-33483996

ABSTRACT

The conceptual basis for a genetic predisposition underlying the risk for developing type 1 diabetes (T1D) predates modern human molecular genetics. Over half of the genetic risk has been attributed to the human leukocyte antigen (HLA) class II gene region and to the insulin (INS) gene locus - both thought to confer direction of autoreactivity and tissue specificity. Notwithstanding, questions still remain regarding the functional contributions of a vast array of minor polygenic risk variants scattered throughout the genome that likely influence disease heterogeneity and clinical outcomes. Herein, we summarize the available literature related to the T1D-associated coding variants defined at the time of this review, for the genes PTPN22, IFIH1, SH2B3, CD226, TYK2, FUT2, SIRPG, CTLA4, CTSH and UBASH3A. Data from genotype-selected human cohorts are summarized, and studies from the non-obese diabetic (NOD) mouse are presented to describe the functional impact of these variants in relation to innate and adaptive immunity as well as to ß-cell fragility, with expression profiles in tissues and peripheral blood highlighted. The contribution of each variant to progression through T1D staging, including environmental interactions, are discussed with consideration of how their respective protein products may serve as attractive targets for precision medicine-based therapeutics to prevent or suspend the development of T1D.


Subject(s)
Diabetes Mellitus, Type 1 , Animals , Diabetes Mellitus, Type 1/genetics , Genetic Predisposition to Disease , Genotype , Mice , Mice, Inbred NOD , Polymorphism, Single Nucleotide
13.
Pharmacogenet Genomics ; 30(9): 208-211, 2020 12.
Article in English | MEDLINE | ID: mdl-32453264

ABSTRACT

The most common adverse drug reaction from statins are statin-associated muscle symptoms (SAMS), characterized by myopathy (weakness), myalgia (muscle pain), and commonly elevation in serum creatine kinase. All statins are substrates of the organic anion transporter 1B1 (OATP1B1; gene: SLCO1B1), albeit to different degrees. A genetic polymorphism in SLCO1B1, c.521T>C (rs4149056), markedly decreases OATP1B1 function. The literature is currently unclear as to whether SLCO1B1 c.521T>C is significantly associated with discontinuation of atorvastatin specifically due to SAMS. Our hypothesis was that individuals carrying the SLCO1B1 decreased function 521C allele are more likely to discontinue atorvastatin due to SAMS. This was a retrospective analysis of survey data from 379 Caucasians genotyped for rs4149056 and treated with atorvastatin for at least 12 months. Crude and multivariable logistic regression, adjusted for established risk factors for SAMS, determined the association of SLCO1B1 c.521T>C with discontinuation of atorvastatin due to SAMS (SLCO1B1 521T-homozygotes vs. 521C-carriers). The sample was 51% male, with a mean age of 57 years (SD = 11). Sixty-one percent of participants reported discontinuing atorvastatin due to SAMS, and 32% overall carried the 521C allele. SLCO1B1 521C-carrier status was not a significant predictor of atorvastatin discontinuation in any model: crude OR = 1.07; 95% CI, 0.68-1.66; P = 0.78 and adjusted OR = 1.07; 95% CI, 0.68-1.69; P = 0.76. The results were similar in a sub-group of participants treated with higher doses of atorvastatin (>20 mg). In summary, SLCO1B1 c.521T>C was not significantly associated with discontinuation of atorvastatin therapy due to SAMS.


Subject(s)
Atorvastatin/adverse effects , Hydroxymethylglutaryl-CoA Reductase Inhibitors/adverse effects , Liver-Specific Organic Anion Transporter 1/genetics , Muscular Diseases/genetics , Muscular Diseases/pathology , Polymorphism, Single Nucleotide , Withholding Treatment/statistics & numerical data , Female , Follow-Up Studies , Genotype , Humans , Male , Middle Aged , Muscular Diseases/chemically induced , Prognosis , Retrospective Studies
14.
Clin Immunol ; 221: 108602, 2020 12.
Article in English | MEDLINE | ID: mdl-33007439

ABSTRACT

OBJECTIVE: This study performed an integrated analysis of the cellular and transcriptional differences in peripheral immune cells between patients with Systemic Lupus Erythematosus (SLE) and healthy controls (HC). METHODS: Peripheral blood was analyzed using standardized flow cytometry panels. Transcriptional analysis of CD4+ T cells was performed by microarrays and Nanostring assays. RESULTS: SLE CD4+ T cells showed an increased expression of oxidative phosphorylation and immunoregulatory genes. SLE patients presented higher frequencies of activated CD38+HLA-DR+ T cells than HC. Hierarchical clustering identified a group of SLE patients among which African Americans were overrepresented, with highly activated T cells, and higher frequencies of Th1, Tfh, and plasmablast cells. T cell activation was positively correlated with metabolic gene expression in SLE patients but not in HC. CONCLUSIONS: SLE subjects presenting with activated T cells and a hyperactive metabolic signature may represent an opportunity to correct aberrant immune activation through targeted metabolic inhibitors.


Subject(s)
CD4-Positive T-Lymphocytes/immunology , CD8-Positive T-Lymphocytes/immunology , Lupus Erythematosus, Systemic/immunology , T-Lymphocyte Subsets/immunology , Adult , Aged , Female , Gene Expression , Humans , Immunophenotyping , Lupus Erythematosus, Systemic/genetics , Middle Aged , Young Adult
15.
J Autoimmun ; 108: 102417, 2020 03.
Article in English | MEDLINE | ID: mdl-32035746

ABSTRACT

IL-12 and IL-18 synergize to promote TH1 responses and have been implicated as accelerators of autoimmune pathogenesis in type 1 diabetes (T1D). We investigated the influence of these cytokines on immune cells involved in human T1D progression: natural killer (NK) cells, regulatory T cells (Tregs), and cytotoxic T lymphocytes (CTL). NK cells from T1D patients exhibited higher surface CD226 versus controls and lower CD25 compared to first-degree relatives and controls. Changes in NK cell phenotype towards terminal differentiation were associated with cytomegalovirus (CMV) seropositivity, while possession of IL18RAP, IFIH1, and IL2RA T1D-risk variants impacted NK cell activation as evaluated by immuno-expression quantitative trait loci (eQTL) analyses. IL-12 and IL-18 stimulated NK cells from healthy donors exhibited enhanced specific killing of myelogenous K562 target cells. Moreover, activated NK cells increased expression of NKG2A, NKG2D, CD226, TIGIT and CD25, which enabled competition for IL-2 upon co-culture with Tregs, resulting in Treg downregulation of FOXP3, production of IFNγ, and loss of suppressive function. We generated islet-autoreactive CTL "avatars", which upon exposure to IL-12 and IL-18, upregulated IFNγ and Granzyme-B leading to increased lymphocytotoxicity of a human ß-cell line in vitro. These results support a model for T1D pathogenesis wherein IL-12 and IL-18 synergistically enhance CTL and NK cell cytotoxic activity and disrupt immunoregulation by Tregs.


Subject(s)
Immunity, Innate , Inflammation/immunology , Killer Cells, Natural/immunology , Killer Cells, Natural/metabolism , Lymphocyte Activation/immunology , T-Lymphocytes, Regulatory/immunology , T-Lymphocytes, Regulatory/metabolism , Adolescent , Adult , Biomarkers , Cells, Cultured , Child , Cytokines/metabolism , Cytotoxicity, Immunologic , Diabetes Mellitus, Type 1/etiology , Diabetes Mellitus, Type 1/metabolism , Disease Susceptibility , Female , Humans , Immunophenotyping , Inflammation/metabolism , Inflammation/pathology , Lymphocyte Count , Male , Middle Aged , Models, Biological , Phenotype , Quantitative Trait Loci , T-Lymphocytes, Cytotoxic/immunology , T-Lymphocytes, Cytotoxic/metabolism , Young Adult
16.
J Card Fail ; 26(8): 664-672, 2020 Aug.
Article in English | MEDLINE | ID: mdl-30753933

ABSTRACT

BACKGROUND: Resting oxygen consumption (VO2) is often estimated and frequently used to guide therapeutic decisions in symptomatic heart failure (HF) patients. The relationship between resting VO2 and symptomatic HF and the accuracy of estimations of VO2 in this population are unknown. METHODS AND RESULTS: We performed a cross-sectional study of HF patients (n = 691) and healthy control subjects (n = 77). VO2 was measured with the use of a metabolic cart, and estimated VO2 was calculated with the use of the Dehmer, LaFarge, and Bergstra formulas and the thermodilution method. The measured and estimated VO2 were compared and the potential impact of estimations determined. In the multivariable model, resting VO2 decreased with increasing New York Heart Association (NYHA) functional class in a stepwise fashion (ß NYHA functional class IV vs control = -36 mL O2/min; P < .001). Estimations of VO2 with the use of derived equations diverged from measured values, particularly for patients with NYHA functional class IV limitations. The percentage difference of measured VO2 versus estimated VO2 was >25% in 39% (n = 271), 25% (n = 170), 82% (n = 566), and 39% (n = 271) of HF patients when using the Dehmer, LaFarge, Bergstra, and thermodilution-derived estimations of VO2 respectively. CONCLUSIONS: Resting VO2 decreases with increasing NYHA functional class and is lower than in control subjects. Using estimations of VO2 to calculate CO may introduce clinically important error.


Subject(s)
Heart Failure , Cardiac Output , Cross-Sectional Studies , Heart Failure/diagnosis , Humans , Oxygen , Oxygen Consumption , Thermodilution
17.
Opt Lett ; 45(7): 1631-1634, 2020 Apr 01.
Article in English | MEDLINE | ID: mdl-32235960

ABSTRACT

By engineering atomic geometries composed of nearly 1000 atomic segments embedded in micro-resonators, we observe Bragg resonances induced by the atomic lattice at the telecommunication wavelength. The geometrical arrangement of erbium atoms into a lattice inside a silicon nitride (SiN) microring resonator reduces the scattering loss at a wavelength commensurate with the lattice. We confirm dependency of light emission to the atomic positions and lattice spacing and also observe Fano interference between resonant modes in the system.

18.
J Appl Clin Med Phys ; 21(4): 59-67, 2020 Apr.
Article in English | MEDLINE | ID: mdl-32170992

ABSTRACT

Pencil beam scanning proton therapy makes possible intensity modulation, resulting in improved target dose conformity and organ-at-risk (OAR) dose sparing. This benefit, however, results in increased sensitivity to certain clinical and beam delivery parameters, such as respiratory motion. These effects can cause plan degeneration, which could lead to decreased tumor dose or increased OAR dose. This study evaluated the measurements of proton pencil beam scanning delivery made with a 2D ion chamber array in solid water on a 1D motion platform, where respiratory motion was simulated using sine and cosine4 waves representing sinusoidal symmetric and realistic asymmetric breathing motions, respectively. Motion amplitudes were 0.5 cm and 1 cm corresponding to 1 cm and 2 cm of maximum respiratory excursions, respectively, with 5 sec fixed breathing cycle. The treatment plans were created to mimic spherical targets of 3 cm or 10 cm diameter located at 5 cm or 1 cm depth in solid water phantom. A reference RBE dose of 200 cGy per fraction was delivered in 1, 5, 10, and 15 fractions for each dataset. We evaluated dose conformity and uniformity at the center plane of targets by using the Conformation Number and the Homogeneity Index, respectively. Results indicated that dose conformity as well as homogeneity was more affected by motion for smaller targets. Dose conformity was better achieved for symmetric breathing patterns than asymmetric breathing patterns regardless of the number of fractions. The presence of a range shifter with shallow targets reduced the motion effect by improving dose homogeneity. While motion effects are known to be averaged out over the course of multifractional treatments, this might not be true for proton pencil beam scanning under asymmetrical breathing pattern.


Subject(s)
Dose Fractionation, Radiation , Movement , Neoplasms/radiotherapy , Proton Therapy/standards , Radiotherapy Dosage , Radiotherapy Planning, Computer-Assisted/methods , Humans , Phantoms, Imaging , Proton Therapy/methods , Protons , Radiometry , Reproducibility of Results , Respiration
19.
BMC Med Res Methodol ; 19(1): 115, 2019 06 06.
Article in English | MEDLINE | ID: mdl-31170931

ABSTRACT

BACKGROUND: Comorbidity measures, such as the Charlson Comorbidity Index (CCI) and Elixhauser Method (EM), are frequently used for risk-adjustment by healthcare researchers. This study sought to create CCI and EM lists of Read codes, which are standard terminology used in some large primary care databases. It also aimed to describe and compare the predictive properties of the CCI and EM amongst patients with hip fracture (and matched controls) in a large primary care administrative dataset. METHODS: Two researchers independently screened 111,929 individual Read codes to populate the 17 CCI and 31 EM comorbidity categories. Patients with hip fractures were identified (together with age- and sex-matched controls) from UK primary care practices participating in the Clinical Practice Research Datalink (CPRD). The predictive properties of both comorbidity measures were explored in hip fracture and control populations using logistic regression models fitted with 30- and 365-day mortality as the dependent variables together with tests of equality for Receiver Operating Characteristic (ROC) curves. RESULTS: There were 5832 CCI and 7156 EM comorbidity codes. The EM improved the ability of a logistic regression model (using age and sex as covariables) to predict 30-day mortality (AUROC 0.744 versus 0.686). The EM alone also outperformed the CCI (0.696 versus 0.601). Capturing comorbidities over a prolonged period only modestly improved the predictive value of either index: EM 1-year look-back 0.645 versus 5-year 0.676 versus complete record 0.695 and CCI 0.574 versus 0.591 versus 0.605. CONCLUSIONS: The comorbidity code lists may be used by future researchers to calculate CCI and EM using records from Read coded databases. The EM is preferable to the CCI but only marginal gains should be expected from incorporating comorbidities over a period longer than 1 year.


Subject(s)
Comorbidity , Hip Fractures/epidemiology , Hospital Mortality , Primary Health Care/statistics & numerical data , Aged , Aged, 80 and over , Databases, Factual , Female , Humans , Logistic Models , Male , ROC Curve , Risk Adjustment , United Kingdom/epidemiology
20.
BMC Musculoskelet Disord ; 20(1): 226, 2019 May 17.
Article in English | MEDLINE | ID: mdl-31101041

ABSTRACT

BACKGROUND: Displaced intracapsular hip fractures are typically treated with hemiarthroplasty (HA) or total hip arthroplasty (THA). A number of professional bodies recommend considering THA for patients that were independently mobile and cognitively intact before injury. The aim of this study was to compare the outcomes between HA and THA for independently mobile older adults with hip fractures. METHODS: A systematic review and meta-analysis of RCTs was undertaken alongside analysis of a propensity score matched national cohort of older adults (aged > 60) with hip fractures. Participants were identified for the propensity score matched cohort from the National Hip Fracture Database (NHFD), which was linked to Hospital Episode Statistics (HES) and civil death registration data. The primary outcomes were 12-month dislocation, revision, and mortality. The secondary outcomes were length of stay, discharge home, unplanned re-admission, functional outcomes, and health-related quality of life. RESULTS: Five RCTs reported higher THA dislocation but this was not statistically significant (THA risk ratio [RR] 2.77, 95% CI 0.81 to 9.48). However, THA dislocation was significantly higher in the national observational dataset (sub-distribution hazard ratio [SHR] 1.73, 95% CI 1.24 to 2.41). Meta-analysis of data from four RCTs did not identify a significant difference in terms of revision (RR 1.52, 95% CI 0.56 to 4.14). However, THA revision was significantly lower in the national dataset (SHR 0.66, 95% CI 0.48 to 0.90). Meta-analysis of data from 5 RCTs suggested higher mortality amongst patients undergoing HA (RR 0.63, 95% CI 0.38 to 1.04), which was also observed within the national registry dataset (hazard ratio 0.45, 95% CI 0.37 to 0.54). CONCLUSIONS: National clinical registries can provide important context when interpreting RCT data, which may alone be inadequate for comparing the safety profile of surgical interventions. These data suggest that THA is at significantly higher risk of dislocation but lower risk of revision within 12 months. The finding from both RCT and clinical registry data that THA is associated with lower 12-month mortality amongst the fittest patients with hip fractures requires urgent further study to determine whether or not this can be replicated in other balanced populations.


Subject(s)
Arthroplasty, Replacement, Hip/adverse effects , Femur Head/injuries , Fracture Dislocation/surgery , Hemiarthroplasty/adverse effects , Hip Fractures/surgery , Postoperative Complications/epidemiology , Age Factors , Aged , Aged, 80 and over , Arthroplasty, Replacement, Hip/methods , Fracture Dislocation/mortality , Hemiarthroplasty/methods , Hip Fractures/mortality , Humans , Independent Living , Middle Aged , Patient Selection , Postoperative Complications/etiology , Quality of Life , Randomized Controlled Trials as Topic , Registries/statistics & numerical data , Reoperation/statistics & numerical data , Risk Factors , United Kingdom/epidemiology
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