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2.
J Pediatr Urol ; 20(3): 442.e1-442.e8, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38286725

ABSTRACT

INTRODUCTION: The aim of this project was to document the long-term outcomes relating to sexual function, genital sensation, body image and quality of life, in an Australian cohort of adolescent and adult women with congenital adrenal hyperplasia (CAH) who have undergone feminising genitoplasty in infancy, childhood or adolescence. MATERIALS AND METHODS: Identification and follow-up of women with CAH aged 12-40 years who had their first feminising genitoplasty or ongoing management at a single tertiary referral center with multidisciplinary care (n = 80). Medical records were reviewed for Prader stage, and operative outcomes. The prospective component of the study included tracing indivudals aged 12-40 years (n = 69), of whom 34 were contactable. Twenty-one responded to the invitation to participate in the study, completing some or all of a series of validated standardized questionnaires and/or participation in examination of external genital with sensation testing. Results were compared to a control population of similar age distribution (n = 23). RESULTS: The median Prader stage was 3, median age at surgery was four months, median hospital stay of three days with 80 % of surgery undertaken by one surgeon. There was one major and eight minor complications. Re-operation rates were low. There was no difference between participants and controls in terms of sexual function, quality of life, or body image outcomes including genital appearance. Participants had increased sensitivity to soft touch on genital sensation testing compared to controls. Most participants (71 %) reported that early timing of surgery was 'good', four (19 %) felt their surgery was too late, one felt their surgery was too early, and one was unsure. Most were happy with the outcome of their surgery. DISCUSSION: Outcomes after feminising genitoplasty are mixed and influenced not only by the surgery itself, but also the ongoing management of the condition alongside each patient's own cultural and social context. At present there is no comparative data available on the sexual, mental, body image and quality of life outcomes of young females with CAH who have had their operation delayed until adulthood. Our study is limited by low participant response rate, and difficulty recruiting 1:1 control population for all participants, but nevertheless provides some insight into the outcomes of these patients for which limited data is available. CONCLUSION: In the population studied feminising genitoplasty in infancy and childhood had overall positive outcomes. This occurred in a tertiary center with expert multidisciplinary individualised care.


Subject(s)
Adrenal Hyperplasia, Congenital , Body Image , Quality of Life , Humans , Adrenal Hyperplasia, Congenital/surgery , Adrenal Hyperplasia, Congenital/complications , Female , Adolescent , Body Image/psychology , Adult , Child , Young Adult , Prospective Studies , Genitalia, Female/surgery , Time Factors , Follow-Up Studies , Postoperative Complications/epidemiology , Surveys and Questionnaires , Sexual Behavior/physiology , Sensation/physiology , Treatment Outcome
3.
bioRxiv ; 2024 Mar 19.
Article in English | MEDLINE | ID: mdl-37873235

ABSTRACT

Telomeres protect chromosome ends and determine the replication potential of dividing cells. The canonical telomere sequence TTAGGG is synthesized by telomerase holoenzyme, which maintains telomere length in proliferative stem cells. Although the core components of telomerase are well-defined, mechanisms of telomerase regulation are still under investigation. We report a novel role for the Src family kinase Fyn, which disrupts telomere maintenance in stem cells by phosphorylating the scaffold protein Menin. We found that Fyn knockdown prevented telomere erosion in human and mouse stem cells, validating the results with four telomere measurement techniques. We show that Fyn phosphorylates Menin at tyrosine 603 (Y603), which increases Menin's SUMO1 modification, C-terminal stability, and importantly, its association with the telomerase RNA component (TR). Using mass spectrometry, immunoprecipitation, and immunofluorescence experiments we found that SUMO1-Menin decreases TR's association with telomerase subunit Dyskerin, suggesting that Fyn's phosphorylation of Menin induces telomerase subunit mislocalization and may compromise telomerase function at telomeres. Importantly, we find that Fyn inhibition reduces accelerated telomere shortening in human iPSCs harboring mutations for dyskeratosis congenita.

4.
bioRxiv ; 2023 Oct 09.
Article in English | MEDLINE | ID: mdl-37873117

ABSTRACT

Transcription Factors (TFs) influence gene expression by facilitating or disrupting the formation of transcription initiation machinery at particular genomic loci. Because genomic localization of TFs is in part driven by TF recognition of DNA sequence, variation in TF binding sites can disrupt TF-DNA associations and affect gene regulation. To identify variants that impact TF binding in human brain tissues, we quantified allele bias for 93 TFs analyzed with ChIP-seq experiments of multiple structural brain regions from two donors. Using graph genomes constructed from phased genomic sequence data, we compared ChIP-seq signal between alleles at heterozygous variants within each tissue sample from each donor. Comparison of results from different brain regions within donors and the same regions between donors provided measures of allele bias reproducibility. We identified thousands of DNA variants that show reproducible bias in ChIP-seq for at least one TF. We found that alleles that are rarer in the general population were more likely than common alleles to exhibit large biases, and more frequently led to reduced TF binding. Combining ChIP-seq with RNA-seq, we identified TF-allele interaction biases with RNA bias in a phased allele linked to 6,709 eQTL variants identified in GTEx data, 3,309 of which were found in neural contexts. Our results provide insights into the effects of both common and rare variation on gene regulation in the brain. These findings can facilitate mechanistic understanding of cis-regulatory variation associated with biological traits, including disease.

5.
Article in English | MEDLINE | ID: mdl-37600843

ABSTRACT

Background: The Association of American Medical Colleges and the American Academy of Orthopaedic Surgeons have incorporated diversity and inclusion as one of their primary goals. Orthopaedic surgery remains the least diverse medical specialty when measured for practicing physicians and trainees. The purpose of this study was to determine the number and distinct types of diversity, equity, and inclusion (DEI) positions within orthopaedic surgery residency programs in the United States. Methods: The Fellowship and Residency Electronic Interactive Database was used to obtain a list of all Accreditation Council for Graduate Medical Education-accredited orthopaedic surgery residency programs. The following was collected from 193 residency program websites between June 6, 2022, and June 26, 2022: program location, university or community based, allopathic or osteopathic recognition, number of faculty in the orthopaedic department, number of residents per year, diversity-related statements, and diversity-focused faculty positions. Results: Of the 193 programs evaluated, 74 (38.9%) included DEI statements on their website while only 42 (21.8%) had at least one DEI-specific faculty role (e.g., diversity committee, diversity liaison, vice chair for DEI). For 16 (8.3%) programs, the faculty role was nonspecific to the orthopaedic residency program. Nonspecific roles were primarily created by the affiliated school of medicine, but in 4 (2.1%) outlier cases, faculty members assumed DEI roles through a medical center, a graduate medical education program, or a department of surgery. Conclusions: Less than half of orthopaedic surgery residency programs currently advocate for DEI on their associated websites while fewer than 25% have a DEI faculty position. Previous studies have called for a greater number of DEI positions and committees among orthopaedic residencies because of the lower admittance rate of qualified Under Represented in Medicine (URiM) applicants. A role dedicated to DEI may increase the number of women and URiM applicants pursuing a career in orthopaedic surgery.

6.
Clin Neurol Neurosurg ; 233: 107916, 2023 10.
Article in English | MEDLINE | ID: mdl-37651797

ABSTRACT

OBJECTIVE: The transfemoral (TF) route has historically been the preferred access site for endovascular procedures. However, despite its widespread use, TF procedures may confer morbidity as a result of access site complications. The aim of this study is to provide the rate and predictors of TF access site complications for neuroendovascular procedures. METHODS: This is a single center retrospective study of TF neuroendovascular procedures performed between 2017 and 2022. The incidence of complications and associated risk factors were analyzed across a large cohort of patients. RESULTS: The study comprised of 2043 patients undergoing transfemoral neuroendovascular procedures. The composite rate of access site complications was 8.6 % (n = 176). These complications were divided into groin hematoma formation (n = 118, 5.78 %), retroperitoneal hematoma (n = 14, 0.69 %), pseudoaneurysm formation (n = 40, 1.96 %), and femoral artery occlusion (n = 4, 0.19 %). The cross-over to trans radial access rate was 1.1 % (n = 22). On univariate analysis, increasing age (OR=1.0, p = 0.06) coronary artery disease (OR=1.7, p = 0.05) peripheral vascular disease (OR=1.9, p = 0.07), emergent mechanical thrombectomy procedures (OR=2.1, p < 0.001) and increasing sheath size (OR=1.3, p < 0.001) were associated with higher TF access site complications. On multivariate analysis, larger sheath size was an independent risk factor for TF access site complications (OR=1.8, p = 0.02). CONCLUSION: Several pertinent factors contribute towards the incidence of TF access site complications. Factors associated with TF access site complications include patient demographics (older age) and clinical risk factors (vascular disease), as well as periprocedural factors (sheath size).


Subject(s)
Endovascular Procedures , Vascular Diseases , Humans , Cohort Studies , Retrospective Studies , Vascular Diseases/etiology , Endovascular Procedures/adverse effects , Endovascular Procedures/methods , Hematoma/epidemiology , Hematoma/etiology , Femoral Artery/surgery , Radial Artery , Treatment Outcome
7.
Transl Psychiatry ; 13(1): 118, 2023 04 08.
Article in English | MEDLINE | ID: mdl-37031222

ABSTRACT

The frontal pole (Brodmann area 10, BA10) is the largest cytoarchitectonic region of the human cortex, performing complex integrative functions. BA10 undergoes intensive adolescent grey matter pruning prior to the age of onset for bipolar disorder (BP) and schizophrenia (SCHIZ), and its dysfunction is likely to underly aspects of their shared symptomology. In this study, we investigated the role of BA10 neurotransmission-related gene expression in BP and SCHIZ. We performed qPCR to measure the expression of 115 neurotransmission-related targets in control, BP, and SCHIZ postmortem samples (n = 72). We chose this method for its high sensitivity to detect low-level expression. We then strengthened our findings by performing a meta-analysis of publicly released BA10 microarray data (n = 101) and identified sources of convergence with our qPCR results. To improve interpretation, we leveraged the unusually large database of clinical metadata accompanying our samples to explore the relationship between BA10 gene expression, therapeutics, substances of abuse, and symptom profiles, and validated these findings with publicly available datasets. Using these convergent sources of evidence, we identified 20 neurotransmission-related genes that were differentially expressed in BP and SCHIZ in BA10. These results included a large diagnosis-related decrease in two important therapeutic targets with low levels of expression, HTR2B and DRD4, as well as other findings related to dopaminergic, GABAergic and astrocytic function. We also observed that therapeutics may produce a differential expression that opposes diagnosis effects. In contrast, substances of abuse showed similar effects on BA10 gene expression as BP and SCHIZ, potentially amplifying diagnosis-related dysregulation.


Subject(s)
Bipolar Disorder , Schizophrenia , Humans , Adolescent , Bipolar Disorder/genetics , Bipolar Disorder/metabolism , Schizophrenia/metabolism , Frontal Lobe/metabolism , Gene Expression , Synaptic Transmission/genetics
8.
Nat Commun ; 13(1): 7074, 2022 11 18.
Article in English | MEDLINE | ID: mdl-36400785

ABSTRACT

Centromere defects in Systemic Sclerosis (SSc) have remained unexplored despite the fact that many centromere proteins were discovered in patients with SSc. Here we report that lesion skin fibroblasts from SSc patients show marked alterations in centromeric DNA. SSc fibroblasts also show DNA damage, abnormal chromosome segregation, aneuploidy (only in diffuse cutaneous (dcSSc)) and micronuclei (in all types of SSc), some of which lose centromere identity while retaining centromere DNA sequences. Strikingly, we find cytoplasmic "leaking" of centromere proteins in limited cutaneous SSc (lcSSc) fibroblasts. Cytoplasmic centromere proteins co-localize with antigen presenting MHC Class II molecules, which correlate precisely with the presence of anti-centromere antibodies. CENPA expression and micronuclei formation correlate highly with activation of the cGAS-STING/IFN-ß pathway as well as markers of reactive oxygen species (ROS) and fibrosis, ultimately suggesting a link between centromere alterations, chromosome instability, SSc autoimmunity, and fibrosis.


Subject(s)
Scleroderma, Diffuse , Scleroderma, Systemic , Humans , Scleroderma, Systemic/metabolism , Chromosomal Instability , Fibrosis , Nucleotidyltransferases/genetics
9.
Plant Physiol ; 190(4): 2315-2334, 2022 11 28.
Article in English | MEDLINE | ID: mdl-35984304

ABSTRACT

Class IV homeodomain leucine-zipper transcription factors (HD-Zip IV TFs) are key regulators of epidermal differentiation that are characterized by a DNA-binding HD in conjunction with a lipid-binding domain termed steroidogenic acute regulatory-related lipid transfer (START). Previous work established that the START domain of GLABRA2 (GL2), a HD-Zip IV member from Arabidopsis (Arabidopsis thaliana), is required for TF activity. Here, we addressed the functions and possible interactions of START and the HD in DNA binding, dimerization, and protein turnover. Deletion analysis of the HD and missense mutations of a conserved lysine (K146) resulted in phenotypic defects in leaf trichomes, root hairs, and seed mucilage, similar to those observed for START domain mutants, despite nuclear localization of the respective proteins. In vitro and in vivo experiments demonstrated that while HD mutations impair binding to target DNA, the START domain is dispensable for DNA binding. Vice versa, protein interaction assays revealed impaired GL2 dimerization for multiple alleles of START mutants, but not HD mutants. Using in vivo cycloheximide chase experiments, we provided evidence for the role of START, but not HD, in maintaining protein stability. This work advances our mechanistic understanding of HD-Zip TFs as multidomain regulators of epidermal development in plants.


Subject(s)
Arabidopsis Proteins , Arabidopsis , Arabidopsis/metabolism , Arabidopsis Proteins/genetics , Arabidopsis Proteins/metabolism , Gene Expression Regulation, Plant , Dimerization , Homeodomain Proteins/metabolism , Leucine Zippers , DNA/metabolism , Lipids
10.
Cureus ; 14(2): e22248, 2022 Feb.
Article in English | MEDLINE | ID: mdl-35340515

ABSTRACT

The posterior tibial vein (PTV) is formed distally by the medial and lateral plantar veins and ends proximally at the joining with the peroneal vein. Variations of the PTV can result in unique clinical presentations. Such variations at the proximal location have been classified previously, but few have been identified distally. In an adult male cadaver, we identified a unilateral distal PTV variation that bifurcated posterior to the medial malleolus. This bifurcation rejoined inferiorly to the medial malleolus and formed a loop that was transected by the posterior tibial artery from deep to superficial. Although this PTV variation is rare, we believe it could be clinically significant for tarsal tunnel syndrome (TTS) and catheter-directed thrombolysis (CDT) of deep vein thrombosis (DVT). Such anatomical variations should be documented and added to clinical databases to improve patient outcomes and diagnostic techniques.

11.
Hernia ; 26(2): 437-445, 2022 04.
Article in English | MEDLINE | ID: mdl-32451792

ABSTRACT

PURPOSE: The use of hernia mesh is a common practice in abdominal wall reconstruction (AWR) operations. The high cost of biologic mesh has raised questions about the value of its use in AWR. Resorbable synthetic mesh may have the potential benefits of biologic mesh, minimizing the need for removal when infected, at a lower cost. METHODS: A hernia program has implemented the principles of clinical quality improvement (CQI) to improve patient outcomes. One process improvement attempt was implemented using a newly available resorbable synthetic scaffold. Long-term follow-up was obtained as a part of the CQI process. RESULTS: A total of 91 patients undergoing AWR were included between 8/11 and 9/15 (49 months). There were 58 female (64%) and 33 male (36%) patients. The average age was 57.2 years (28-80). The average BMI was 34.0 (17.6-53.4). There were 52 patients (57%) with recurrent hernias. Mean hernia defect size was 306.6 cm2 (24-720) and mean mesh size was 471.7 cm2 (112-600). Outcomes included a mean length of stay of 7.5 days (0-49), a recurrence rate of 12% (11/91) and a wound complication rate of 27% (25/91). The recurrence rate decreased to 4.5% (3/66) after several improvements, including adopting a transversus abdominus release (TAR) approach, were implemented. There were no mesh-related complications and no mesh removal (partial or total) was required. The mean follow-up length was 42.4 months (0-102). CONCLUSION: In this group of patients, an attempt at process improvement was implemented using a resorbable synthetic scaffold for AWR. With no mesh-related complications and no mesh removals required, there was an improvement in value due to the decrease in mesh cost and improved outcomes over time. Long-term follow-up demonstrated the durability of the repair.


Subject(s)
Abdominal Wall , Hernia, Ventral , Abdominal Wall/surgery , Female , Hernia, Ventral/etiology , Hernia, Ventral/surgery , Herniorrhaphy/adverse effects , Humans , Male , Middle Aged , Quality Improvement , Recurrence , Retrospective Studies , Surgical Mesh/adverse effects , Treatment Outcome
12.
Ann R Coll Surg Engl ; 104(3): 174-180, 2022 Mar.
Article in English | MEDLINE | ID: mdl-34822303

ABSTRACT

INTRODUCTION: Men with gynaecomastia are routinely referred to breast clinics, yet most do not require breast surgical intervention. The aim of this study was to assess the impact of a novel point-of-care gynaecomastia decision infographic in primary care on the assessment, management and referral practices to tertiary breast surgical services. METHODS: A study was carried out of male patient referrals from primary care in Greater Manchester to a tertiary breast centre between January and March in 2018-2020. Referral patterns were compared before and after the infographic went live in general practices in Greater Manchester in January 2020. Data were collected for gynaecomastia referrals, including aetiology, investigation and management. RESULTS: In total, 394 men were referred to a tertiary breast centre from 163 general practices, of which 271 (68.8%) had a diagnosis of gynaecomastia. Use of the decision infographic by primary healthcare providers was associated with a decrease in male breast referrals with gynaecomastia (79.6% to 62.0%). Fewer gynaecomastia patients were referred with a benign physiological or drug-related cause after implementation of the infographic (52.2% vs 41.8%). Only 10 (3.7%) patients with gynaecomastia underwent breast surgery during the study period. CONCLUSION: Implementation of a gynaecomastia infographic in primary care in Manchester was associated with a reduction in gynaecomastia referrals to secondary care. We hypothesise that implementation of the infographic into primary care nationally may potentially translate to hundreds of patients receiving more specialty-appropriate referrals, improving overall management of gynaecomastia. Further study is warranted to test this hypothesis.


Subject(s)
Clinical Decision-Making , Data Visualization , Gynecomastia , Primary Health Care/methods , Referral and Consultation/statistics & numerical data , Adult , Aged , Gynecomastia/diagnosis , Gynecomastia/epidemiology , Gynecomastia/therapy , Humans , Male , Middle Aged , Practice Guidelines as Topic , United Kingdom
13.
Appl Clin Inform ; 12(5): 969-978, 2021 10.
Article in English | MEDLINE | ID: mdl-34670292

ABSTRACT

OBJECTIVE: To develop and evaluate an electronic tool that collects interval history and incorporates it into a provider summary note. METHODS: A parent-facing online before-visit questionnaire (BVQ) collected information from parents and caregivers of pediatric diabetes patients prior to a clinic encounter. This information was related to interval history and perceived self-management barriers. The BVQ generated a summary note that providers could paste in their own documentation. Parents also completed postvisit experience questionnaires. We assessed the BVQs perceived usefulness to parents and providers and compared provider documentation content and length pre- and post-BVQ rollout. We interviewed providers regarding their experiences with the system-generated note. RESULTS: Seventy-three parents of diabetic children were recruited and completed the BVQ. A total of 79% of parents stated that the BVQ helped with visit preparation and 80% said it improved perceived quality of visits. All 16 participating providers reviewed BVQs prior to patient encounters and 100% considered the summary beneficial. Most providers (81%) desired summaries less than 1 week old. A total of 69% of providers preferred the prose version of the summary; however, 75% also viewed the bulleted version as preferable for provider review. Analysis of provider notes revealed that BVQs increased provider documentation of patients' adherence and barriers. We observed a 50% reduction in typing by providers to document interval histories. Providers not using summaries typed an average of 137 words (standard deviation [SD]: 74) to document interval history compared with 68 words [SD 47] typed with BVQ use. DISCUSSION: Providers and parents of children with diabetes appreciated the use of previsit, parent-completed BVQs that automatically produced provider documentation. Despite the BVQ redistributing work from providers to parents, its use was acceptable to both groups. CONCLUSION: Parent-completed questionnaires on the patient's behalf that generate provider documentation encourage communication between parents and providers regarding disease management and reduce provider workload.


Subject(s)
Diabetes Mellitus , Documentation , Child , Communication , Humans , Parents , Surveys and Questionnaires
14.
Urol Oncol ; 39(12): 834.e1-834.e7, 2021 12.
Article in English | MEDLINE | ID: mdl-34162500

ABSTRACT

PURPOSE: To compare healthcare resource utilization (HRU) and costs associated with dose-dense methotrexate, vinblastine, doxorubicin, cisplatin (ddMVAC) and gemcitabine, cisplatin (GC) as neoadjuvant chemotherapy for muscle-invasive bladder cancer (MIBC). METHODS: Patient treated at Dana-Farber Cancer Institute from 2010 to 2019 were identified. HRU data on chemotherapy administered, supportive medications, patient monitoring, clinic, infusion, emergency department (ED) visits and hospitalization were collected retrospectively. Unit costs for HRU components were obtained from the Centers for Medicare and Medicaid Website and HRU was compared between groups using quantile regression analysis. RESULTS: 137 patients were included; 51 received ddMVAC and 86 GC. Baseline characteristics were similar, except lower mean age (P < 0.001) and higher proportion of ECOG-PS = 0 (P < 0.001) for ddMVAC. ddMVAC required more granulocyte-colony stimulating factor support (P < 0.001), central line placement (P = 0.017), cardiac imaging (P < 0.001), and infusion visits (P < 0.001), whereas GC required more clinic visits. ED visits were higher for ddMVAC (P = 0.048), while chemotherapy cycle delays and hospitalization days were higher for GC (P = 0.008). After adjusting for ECOG-PS and age, the cost per patient was approximately 41% lower (95%CI: 28% to 52%; P < 0.001) for GC vs. ddMVAC, which translated to a median adjusted cost savings of $7,410 (95%CI: $5,474-$9,347) per patient. CONCLUSIONS: Although excess HRU did not clearly favor one regimen, adjusting for PS and age indicated lower costs with GC vs. ddMVAC. Given the similar cumulative cisplatin delivery with both regimens, the associated values and costs supports the preferential selection of GC in the neoadjuvant setting of MIBC.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Cisplatin/therapeutic use , Delivery of Health Care/economics , Deoxycytidine/analogs & derivatives , Doxorubicin/therapeutic use , Methotrexate/therapeutic use , Neoadjuvant Therapy/methods , Urinary Bladder Neoplasms/drug therapy , Urinary Bladder Neoplasms/economics , Vinblastine/therapeutic use , Adult , Aged , Antineoplastic Combined Chemotherapy Protocols/pharmacology , Cisplatin/pharmacology , Deoxycytidine/pharmacology , Deoxycytidine/therapeutic use , Doxorubicin/pharmacology , Female , Humans , Male , Methotrexate/pharmacology , Middle Aged , Prospective Studies , Retrospective Studies , Vinblastine/pharmacology , Gemcitabine
15.
Chem Soc Rev ; 50(13): 7378-7394, 2021 Jul 07.
Article in English | MEDLINE | ID: mdl-34018500

ABSTRACT

Large quantities of fluorinated gases are generated as intermediates or byproducts from fluorinated polymer production annually, and they are effective ozone depleting substances or greenhouse gases. On the other hand, the incorporation of fluoroalkyl groups into drug molecules or bioactive compounds has been shown to enhance biological properties such as the bioavailability, binding selectivity, and metabolic stability. Extraction of fluoroalkyl sources, including trifluoromethyl and difluoromethyl groups, from the fluorinated gases is highly desirable, yet challenging under regular batch reaction conditions. Flow chemistry is an emerging and promising technique to address long-standing challenges in gas-liquid batch reactions such as insufficient interfacial contact and scalability issues. In this review, we highlight recent advances in continuous flow strategies toward enabling the use of fluorinated greenhouse gases in organic synthesis.

16.
Acta Physiol (Oxf) ; 231(4): e13627, 2021 04.
Article in English | MEDLINE | ID: mdl-33580591

ABSTRACT

AIM: Loss of dystrophin causes oxidative stress and affects nitric oxide synthase-mediated vascular function in striated muscle. Because tetrahydrobiopterin is an antioxidant and co-factor for nitric oxide synthase, we tested the hypothesis that tetrahydrobiopterin would be low in mdx mice and humans deficient for dystrophin. METHODS: Tetrahydrobiopterin and its metabolites were measured at rest and in response to exercise in Duchenne and Becker muscular dystrophy patients, age-matched male controls as well as wild-type, mdx and mdx mice transgenically overexpressing skeletal muscle-specific dystrophins. Mdx mice were also supplemented with tetrahydrobiopterin and pathophysiology was assessed. RESULTS: Duchenne muscular dystrophy patients had lower urinary dihydrobiopterin + tetrahydrobiopterin/specific gravity1.020 compared to unaffected age-matched males and Becker muscular dystrophy patients. Mdx mice had low urinary and skeletal muscle dihydrobiopterin + tetrahydrobiopterin compared to wild-type mice. Overexpression of dystrophins that localize neuronal nitric oxide synthase restored dihydrobiopterin + tetrahydrobiopterin in mdx mice to wild-type levels while utrophin overexpression did not. Mdx mice and Duchenne muscular dystrophy patients did not increase tetrahydrobiopterin during exercise and in mdx mice tetrahydrobiopterin deficiency was likely because of lower levels of sepiapterin reductase in skeletal muscle. Tetrahydrobiopterin supplementation improved skeletal muscle strength, resistance to fatiguing and injurious contractions in vivo, increased utrophin and capillary density of skeletal muscle and lowered cardiac muscle fibrosis and left ventricular wall thickness in mdx mice. CONCLUSION: These data demonstrate that impaired tetrahydrobiopterin synthesis is associated with dystrophin loss and treatment with tetrahydrobiopterin improves striated muscle histopathology and skeletal muscle function in mdx mice.


Subject(s)
Dystrophin , Muscular Dystrophy, Duchenne , Animals , Biopterins/analogs & derivatives , Humans , Male , Mice , Mice, Inbred mdx , Muscle, Skeletal , Utrophin
17.
Dalton Trans ; 50(2): 599-611, 2021 Jan 19.
Article in English | MEDLINE | ID: mdl-33403375

ABSTRACT

Exposure of 10π-electron benzazaphosphole 1 to HCl, followed by nucleophilic substitution with the Grignard reagent BrMgCCPh afforded alkynyl functionalized 3 featuring an exocyclic -C[triple bond, length as m-dash]C-Ph group with an elongated P-C bond (1.7932(19) Å). Stoichiometric experiments revealed that treatment of trans-Pd(PEt3)2(Ar)(i) (Ar = p-Me (C) or p-F (D)) with 3 generated trans-Pd(PEt3)2(Ar)(CCPh) (Ar = p-Me (E) or p-F (F)), 5, which is the result of ligand exchange between P-I byproduct 4 and C/D, and the reductively eliminated product (Ar-C[triple bond, length as m-dash]C-Ph). Cyclic voltammetry studies showed and independent investigations confirmed 4 is also susceptible to redox processes including bimetallic oxidative addition to Pd(0) to give Pd(i) dimer 6-Pd2-(P(t-Bu)3)2 and reduction to diphosphine 7. During catalysis, we hypothesized that this unwanted reactivity could be circumvented by employing a source of fluoride as an additive. This was demonstrated by conducting a Sonogashira-type reaction between 1-iodotoluene and 3 in the presence of 10 mol% Na2PdCl4, 20 mol% P(t-Bu)Cy2, and 5 equiv. of tetramethylammonium fluoride (TMAF), resulting in turnover and the isolation of Ph-C[triple bond, length as m-dash]C-(o-Tol) as the major product.


Subject(s)
Alkynes/chemistry , Organophosphorus Compounds/chemistry , Palladium/chemistry , Oxidation-Reduction
18.
Clin Microbiol Infect ; 26(4): 492-498, 2020 Apr.
Article in English | MEDLINE | ID: mdl-31525517

ABSTRACT

OBJECTIVES: Clostridium difficile is a major global human pathogen divided into five clades, of which clade 3 is the least characterized and consists predominantly of PCR ribotype (RT) 023 strains. Our aim was to analyse and characterize this clade. METHODS: In this cohort study the clinical presentation of C. difficile RT023 infections was analysed in comparison with known 'hypervirulent' and non-hypervirulent strains, using data from the Netherlands national C. difficile surveillance programme. European RT023 strains of diverse origin were collected and whole-genome sequenced to determine the genetic similarity between isolates. Distinctive features were investigated and characterized. RESULTS: Clinical presentation of C. difficile RT023 infections show severe infections akin to those seen with 'hypervirulent' strains from clades 2 (RT027) and 5 (RT078) (35%, 29% and 27% severe CDI, respectively), particularly with significantly more bloody diarrhoea than RT078 and non-hypervirulent strains (RT023 8%, other RTs 4%, p 0.036). The full genome sequence of strain CD305 is presented as a robust reference. Phylogenetic comparison of CD305 and a further 79 previously uncharacterized European RT023 strains of diverse origin revealed minor genetic divergence with >99.8% pairwise identity between strains. Analyses revealed distinctive features among clade 3 strains, including conserved pathogenicity locus, binary toxin and phage insertion toxin genotypes, glycosylation of S-layer proteins, presence of the RT078 four-gene trehalose cluster and an esculinase-negative genotype. CONCLUSIONS: Given their recent emergence, virulence and genomic characteristics, the surveillance of clade 3 strains should be more highly prioritized.


Subject(s)
Clostridioides difficile/classification , Clostridioides difficile/pathogenicity , Clostridium Infections/microbiology , Adolescent , Adult , Aged , Aged, 80 and over , Bacterial Typing Techniques , Child , Child, Preschool , Clostridium Infections/epidemiology , Cohort Studies , Diarrhea/microbiology , Female , High-Throughput Nucleotide Sequencing , Hospitals/statistics & numerical data , Humans , Infant , Male , Middle Aged , Multilocus Sequence Typing , Netherlands/epidemiology , Phylogeny , Ribotyping , Sentinel Surveillance , Young Adult
19.
Curr Opin Ophthalmol ; 30(6): 506-512, 2019 Nov.
Article in English | MEDLINE | ID: mdl-31589187

ABSTRACT

PURPOSE OF REVIEW: The United States has experienced a dramatic rise in opioid and injection drug use over the past 2 decades. A public health emergency was declared in 2017 and subsequently, there have been several new reports on the rise of endogenous endophthalmitis specifically associated with injection drug use. The purpose of this review is to provide a current perspective of the ocular harms posed by injection drug use. RECENT FINDINGS: The opioid epidemic has prompted several new studies from New England, one of the US regions most heavily affected, that examine the trends and characteristics of injection drug use-associated endogenous endophthalmitis. Patients may delay seeking care and may be infected with a variety of rare and atypical microbes, and as a result clinical appearance may vary widely. Injection drug use also leads to embolic phenomena such as talc retinopathy and septic emboli from endocarditis. HIV is highly associated with injection drug use and although HAART has drastically reduced the morbidity and mortality of HIV-associated infections, a variety of ocular disease may accompany an immunocompromised patient. SUMMARY: Healthcare providers must remain vigilant in the recognition of injection drug use patients with vision loss and ocular inflammation to ensure prompt medical and/or surgical treatment.


Subject(s)
Endophthalmitis/etiology , Opioid Epidemic , Substance Abuse, Intravenous/etiology , Humans
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