Introduction
The life expectancy of Pompe disease patients has increased due to improved neonatal screening and enzyme replacement therapy. Nevertheless, the potential effect of frequent medical ...device exposure on pubertal development in these patients is not well understood, so further investigation is warranted.
Methods
In this cross-sectional study, we assessed the growth and puberty of nine Pompe disease patients. In addition, to determine the effects of frequent plastic medical device exposure in these patients, we measured urinary phthalate metabolites before and one day after enzyme replacement therapy.
Results
Five out of nine patients (55%) with Pompe disease on enzyme replacement therapy had precocious puberty. Patients with precocious puberty had significantly shorter predicted adult heights compared to those with normal puberty (
p
= 0.014). The levels of mono-2-ethylhexyl phthalate (MEHP) and mono(2-ethyl-5-carboxypentyl) phthalate (MECPP) increased after enzyme replacement therapy, but the average levels of phthalate metabolites did not significantly differ between patients with normal and precocious puberty.
Conclusion
Pompe disease patients on enzyme replacement therapy tend to have precocious puberty, which may reduce their adult height. There are no significant differences in urinary phthalate metabolites between normal and precocious puberty patients. Regular follow-up of growth and puberty in Pompe disease patients is important to improve their health outcomes.
The ability of staphylococci to grow in a wide range of salt concentrations is well documented. In this study, we aimed to clarify the role of cardiolipin (CL) in the adaptation of Staphylococcus ...aureus to high salinity.
Using an improved extraction method, the analysis of phospholipid composition suggested that CL levels increased slightly toward stationary phase, but that this was not induced by high salinity. Deletion of the two CL synthase genes, SA1155 (cls1) and SA1891 (cls2), abolished CL synthesis. The cls2 gene encoded the dominant CL synthase. In a cls2 deletion mutant, Cls1 functioned under stress conditions, including high salinity. Using these mutants, CL was shown to be unnecessary for growth in either basal or high-salt conditions, but it was critical for prolonged survival in high-salt conditions and for generation of the L-form.
CL is not essential for S. aureus growth under conditions of high salinity, but is necessary for survival under prolonged high-salt stress and for the generation of L-form variants.
It has long been a question whether Staphylococcus aureus, a major human pathogen, is able to develop natural competence for transformation by DNA. We previously showed that a novel staphylococcal ...secondary sigma factor, SigH, was a likely key component for competence development, but the corresponding gene appeared to be cryptic as its expression could not be detected during growth under standard laboratory conditions. Here, we have uncovered two distinct mechanisms allowing activation of SigH production in a minor fraction of the bacterial cell population. The first is a chromosomal gene duplication rearrangement occurring spontaneously at a low frequency ≤10(-5), generating expression of a new chimeric sigH gene. The second involves post-transcriptional regulation through an upstream inverted repeat sequence, effectively suppressing expression of the sigH gene. Importantly, we have demonstrated for the first time that S. aureus cells producing active SigH become competent for transformation by plasmid or chromosomal DNA, which requires the expression of SigH-controlled competence genes. Additionally, using DNA from the N315 MRSA strain, we successfully transferred the full length SCCmecII element through natural transformation to a methicillin-sensitive strain, conferring methicillin resistance to the resulting S. aureus transformants. Taken together, we propose a unique model for staphylococcal competence regulation by SigH that could help explain the acquisition of antibiotic resistance genes through horizontal gene transfer in this important pathogen.
IntroductionA significant proportion of individuals suffering from post COVID-19 condition (PCC, also known as long COVID) can present with persistent, disabling fatigue similar to myalgic ...encephalomyelitis/chronic fatigue syndrome (ME/CFS) and post-viral fatigue syndromes. There remains no clear pharmacological therapy for patients with this subtype of PCC, which can be referred to as post-COVID fatigue syndrome (PCFS). A low dose of the opioid antagonist naltrexone (ie, low-dose naltrexone (LDN)) has emerged as an off-label treatment for treating fatigue and other symptoms in PCC. However, only small, non-controlled studies have assessed LDN in PCC, so randomised trials are urgently required.Methods and analysisA prospective, randomised, double-blind, parallel arm, placebo-controlled phase II trial will be performed to assess the efficacy of LDN for improving fatigue in PCFS. The trial will be decentralised and open to eligible individuals throughout the Canadian province of British Columbia (BC). Participants will be recruited through the province-wide Post-COVID-19 Interdisciplinary Clinical Care Network (PC-ICCN) and research volunteer platform (REACH BC). Eligible participants will be 19–69 years old, have had a confirmed or physician-suspected SARS-CoV-2 infection at least 3 months prior and meet clinical criteria for PCFS adapted from the Institute of Medicine ME/CFS criteria. Individuals who are taking opioid medications, have a history of ME/CFS prior to COVID-19 or history of significant liver disease will be excluded. Participants will be randomised to an LDN intervention arm (n=80) or placebo arm (n=80). Participants in each arm will be prescribed identical capsules starting at 1 mg daily and follow a prespecified schedule for up-titration to 4.5 mg daily or the maximum tolerated dose. The trial will be conducted over 16 weeks, with assessments at baseline, 6, 12 and 16 weeks. The primary outcome will be fatigue severity at 16 weeks evaluated by the Fatigue Severity Scale. Secondary outcomes will include pain Visual Analogue Scale score, overall symptom severity as measured by the Patient Phenotyping Questionnaire Short Form, 7-day step count and health-related quality of life measured by the EuroQol 5-Dimension questionnaire.Ethics and disseminationThe trial has been authorised by Health Canada and approved by The University of British Columbia/Children’s and Women’s Health Centre of British Columbia Research Ethics Board. On completion, findings will be disseminated to patients, caregivers and clinicians through engagement activities within existing PCC and ME/CFS networks. Results will be published in academic journals and presented at conferences.Trial registration number NCT05430152.
Autosomal recessive hypophosphatemic rickets (HR) type 2 (ARHR2) is a rare form of HR caused by variant of the gene encoding ectonucleotide pyrophosphatase/phosphodiesterase 1 (ENPP1). Our patient ...presented with a history of unsteady gait and progressively bowing legs that had commenced at the age of 1 year. Laboratory tests revealed an elevated level of fibroblast growth factor 23 (FGF23), hypophosphatemia, and a high urine phosphate level. Radiography revealed the typical features of rickets. Next-generation sequencing identified a previously reported c.783C>G (p.Tyr261Ter) and a novel c.1092-42A>G variant in the ENPP1 gene. The patient was prescribed oral phosphates and active vitamin D and underwent guided growth of both distal femora and proximal tibiae commencing at the age of 3 years. No evidence of generalized arterial calcification was apparent during follow-up, and growth rate was satisfactory.Autosomal recessive hypophosphatemic rickets (HR) type 2 (ARHR2) is a rare form of HR caused by variant of the gene encoding ectonucleotide pyrophosphatase/phosphodiesterase 1 (ENPP1). Our patient presented with a history of unsteady gait and progressively bowing legs that had commenced at the age of 1 year. Laboratory tests revealed an elevated level of fibroblast growth factor 23 (FGF23), hypophosphatemia, and a high urine phosphate level. Radiography revealed the typical features of rickets. Next-generation sequencing identified a previously reported c.783C>G (p.Tyr261Ter) and a novel c.1092-42A>G variant in the ENPP1 gene. The patient was prescribed oral phosphates and active vitamin D and underwent guided growth of both distal femora and proximal tibiae commencing at the age of 3 years. No evidence of generalized arterial calcification was apparent during follow-up, and growth rate was satisfactory.
Short stature and intellectual disability are two of the major components of many dysmorphic syndromes. Jansen–de Vries syndrome (JDVS) is a rare syndromic disorder that was discovered recently using ...next-generation sequencing. It is characterized by hypotonia, developmental delay, a dysmorphic face, short stature, and high pain threshold and is caused by the variants of the protein phosphatase magnesium-dependent 1D (PPM1D) gene. Here, we report the first two cases of PPM1D mutations in Taiwan; both had de novo variants in exon 6. Both presented with short stature, developmental delay, and dysmorphic faces. In addition to the characteristics listed above, syndactyly was noted in one. Genetic studies should be considered when approaching a patient with growth retardation, intellectual disability, and other major or minor dysmorphisms.
Abstract
Lysosomal storage diseases (LSDs) are a group of metabolic disorders resulting from a deficiency in one of the lysosomal hydrolases. Most LSDs are inherited in an autosomal or X-linked ...recessive manner. As LSDs are rare, their true incidence in Taiwan remains unknown. In this study, we used high-coverage whole-genome sequencing data from 1,495 Taiwanese individuals obtained from the Taiwan Biobank. We found 3826 variants in 71 genes responsible for autosomal recessive LSDs. We first excluded benign variants by allele frequency and other criteria. As a result, 270 variants were considered disease-causing. We curated these variants using published guidelines from the American College of Medical Genetics and Genomics (ACMG). Our results revealed a combined incidence rate of 13 per 100,000 (conservative estimation by pathologic and likely pathogenic variants; 95% CI 6.92-22.23) to 94 per 100,000 (extended estimation by the inclusion of variants of unknown significance; 95% CI 75.96–115.03) among 71 autosomal recessive disease-associated genes. The conservative estimations were similar to those in published clinical data. No disease-causing mutations were found for 18 other diseases; thus, these diseases are likely extremely rare in Taiwan. The study results are important for designing screening and treatment methods for LSDs in Taiwan and demonstrate the importance of mutation curation to avoid overestimating disease incidences from genomic data.
Abstract
Hoyeraal-Hreidarsson syndrome (HHS) is the most severe form of dyskeratosis congenita (DC) and is caused by mutations in genes involved in telomere maintenance. Here, we identified male ...siblings from a family with HHS carrying a hemizygous mutation (c.1345C > G, p.R449G), located in the C-terminal nuclear localization signal (NLS) of the
DKC1
gene. These patients exhibit progressive cerebellar hypoplasia, recurrent infections, pancytopenia due to bone marrow failure, and short leukocyte telomere lengths. Single-cell RNA sequencing analysis suggested defects in the NLRP3 inflammasome in monocytes and the activation and maturation of NK cells and B cells. In experiments using induced pluripotent stem cells (iPSCs) from patients, DKC1_R449G iPSCs had short telomere lengths due to reduced levels of human telomerase RNA (hTR) and increased cytosolic proportions of DKC1. Treatment with dihydroquinolizinone RG7834 and 3′deoxyanosine cordycepin rescued telomere length in patient-derived iPSCs. Together, our findings not only provide new insights into immunodeficiency in DC patients but also provide treatment options for telomerase insufficiency disorders.
Abstract
Background
Though outcome differences between children and adults with immunoglobulin A vasculitis (IgAV) has been well documented, it remains unclear if disease features in pediatric IgAV ...patients vary with onset age. We aimed to explore clinical features and prognosis of pediatric IgAV stratified by onset age.
Methods
We retrospectively reviewed records of patients under 18 years old diagnosed with IgAV from January 1999 to December 2018 in one tertiary medical center in Taiwan. Patients were grouped by onset age: ≤ 6 years old, 6–12 years old (> 6, ≤ 12), and 12–18 years old (> 12, < 18). Demographics, laboratory data, incidence of gastrointestinal, renal, and joint involvement, corticosteroid dependence, recurrence, and refractory disease were analyzed. Recurrence was defined as disease flare-up after complete remission and discontinuation of all medications for at least 3 months. Corticosteroid dependence was defined by more than 6 weeks of daily oral corticosteroid intake. Refractory disease was defined as not achieving complete remission 6 months after disease onset. Statistical analysis was performed using R software (v3.6.0).
Results
There were 484 IgAV patients, with an onset age of 6.10 (4.72–8.58) (median (IQR)) years old. There were 234 (48.3%) patients ≤6 years old, 210 (43.4%) 6–12 years old, and 40 (8.3%) 12–18 years old. One hundred and thirty (26.9%) patients had renal involvement, which was more frequent in older children (≤ 6 years old, 18.4%; 6–12 years old, 31.0%; 12–18 years old, 55.0%;
p
< 0.001). There were 361 patients (74.6%) with joint involvement; younger children were affected more frequently (≤ 6 years old, 82.1%; 6–12 years old, 71.9%; 12–18 years old, 45.0%;
p
< 0.001). Gastrointestinal involvement was present in 311 (64.3%) patients, showing no difference among age groups. There were 46 patients (9.5%) with recurrent IgA vasculitis, 136 (28.1%) with corticosteroid dependent and 76 (15.7%) with refractory disease. Corticosteroid dependence and refractory disease occurred more frequently as onset age increased (
p
< 0.001).
Conclusion
Pediatric IgAV with different onset ages are associated with distinct clinical manifestations and outcomes. The risk of developing corticosteroid dependence, refractory disease and renal involvement increased with onset age.
Increasing evidence on long-term health outcomes following SARS CoV-2 infection shows post-viral symptoms can persist for months. These symptoms are often consistent with those of Myalgic ...Encephalomyelitis or Chronic Fatigue Syndrome (ME/CFS). The aim of the present study was to examine the prevalence and outcome predictors of post-viral fatigue and related symptoms 3- and 6-months following symptom onset.
A prospective cohort of patients hospitalized with Coronavirus disease (COVID-19) (
= 88) were recruited from a Post-COVID-19 Respiratory Clinic (PCRC) in Vancouver, Canada to examine predictors of long-term fatigue and substantial fatigue. Multivariable mixed effects analyses examined the relationship between patient predictors, including pre-existing comorbidities, patient reported outcome measures, and fatigue and substantial fatigue at follow-up.
The number of patients experiencing fatigue or substantial fatigue at 3 months post-infection were 58 (67%) and 14 (16%) respectively. At 6 months these numbers declined to 47 (60%) patients experiencing fatigue and 6 (6%) experiencing substantial fatigue. Adjusted analysis, for sex, age, and time, revealed the number of pre-existing comorbidities to be associated with fatigue (OR 2.21; 95% CI 1.09-4.49; 0.028) and substantial fatigue (OR 1.73; 95% CI 1.06-2.95; 0.033) at 3 months follow-up. Except for shortness of breath, self-care, and follow-up time, all follow-up variables were found to be associated with fatigue and substantial fatigue at 3 months.
Fatigue and substantial fatigue are common after COVID-19 infection but often diminish over time. A significant number of patients continue to exhibit long-term fatigue at 6 months follow-up. Further research is needed to clarify the causality of viral infections in the development and severity of fatigue as a symptom and in meeting post-viral fatigue syndrome or ME/CFS diagnostic criteria.