Abstract Martsolf syndrome is characterized by congenital cataracts, postnatal microcephaly, developmental delay, hypotonia, short stature and biallelic hypomorphic mutations in either RAB3GAP1 or RAB3GAP2. Through genetic analysis of 85 unrelated “mutation negative” probands referred with Martsolf syndrome we identified two individuals with different homozygous null mutations in ITPA , the gene encoding inosine triphosphate pyrophosphatase (ITPase). The probands reported here each presented with a lethal and highly distinctive disorder; Martsolf syndrome with infantile-onset dilated cardiomyopathy. Severe ITPase-deficiency has been previously reported with infantile epileptic encephalopathy (MIM 616647). ITPase acts to prevent incorporation of inosine bases (rl/dl) into RNA and DNA. In Itpa -null cells, dI was undetectable in genomic DNA. dI could be identified at a low level in mtDNA but this was not associated with detectable mitochondrial genome instability, mtDNA depletion or biochemical dysfunction of the mitochondria. rI accumulation was detectable in lymphoblastoid RNA from an affected individual. In Itpa -null mouse embryos rI was detectable in the brain and kidney with the highest level seen in the embryonic heart (rI at 1 in 385 bases). Transcriptome and proteome analysis in mutant cells revealed no major differences with controls. The rate of transcription and the total amount of cellular RNA also appeared normal. rI accumulation in RNA – and by implication rI production - correlates with the severity of organ dysfunction in ITPase deficiency but the basis of the cellulopathy remains cryptic. While we cannot exclude cumulative minor effects, there are no major anomalies in the production, processing, stability and/or translation of mRNA. Author Summary Nucleotide triphosphate bases containing inosine, ITP and dITP, are continually produced within the cell as a consequence of various essential biosynthetic reactions. The enzyme inosine triphosphate pyrophosphatase (ITPase) scavenges ITP and dITP to prevent their incorporation into RNA and DNA. Here we describe two unrelated families with complete loss of ITPase function as a consequence of disruptive mutations affecting both alleles of ITPA , the gene that encodes this protein. Both of the families have a very distinctive and severe combination of clinical problems, most notably a failure of heart muscle that was lethal in infancy or early childhood. They also have features of another rare genetic disorder affecting the brain and the eyes called Martsolf syndrome. We could not detect any evidence of dITP accumulation in genomic DNA from the affected individuals. A low but detectable level of inosine was present in the mitochondrial DNA but this did not have any obvious detrimental effect. The inosine accumulation in RNA was detectable in the patient cells. We made both cellular and animal models that were completely deficient in ITPase. Using these reagents we could show that the highest level of inosine accumulation into RNA was seen in the embryonic mouse heart. In this tissue more than 1 in 400 bases in all RNA in the cell was inosine. In normal tissues inosine is almost undetectable using very sensitive assays. The inosine accumulation did not seem to be having a global effect on the balance of RNA molecules or proteins.
Much of routine cancer care has been disrupted due to the perceived susceptibility to SARS-CoV-2 infection in cancer patients. Here, we systematically review the current evidence base pertaining to the prevalence, presentation and outcome of COVID-19 in cancer patients, in order to inform policy and practice going forwards. A keyword-structured systematic search was conducted on Pubmed, Cochrane, Embase and MedRxiv databases for studies reporting primary data on COVID-19 in cancer patients. Studies were critically appraised using the NIH National Heart, Lung and Blood Institute's quality assessment tool set. The pooled prevalence of cancer as a co-morbidity in patients with COVID-19 and pooled in-hospital mortality risk of COVID-19 in cancer patients were derived by random-effects meta-analyses. In total, 110 studies from 10 countries were included. The pooled prevalence of cancer as a co-morbidity in hospitalised patients with COVID-19 was 2.6% (95% confidence interval 1.8%, 3.5%, I
Abstract Objectives To estimate COVID-19 infections and deaths in healthcare workers (HCWs) from a global perspective. Design Scoping review. Methods Two parallel searches of academic bibliographic databases and grey literature were undertaken. Governments were also contacted for further information where possible. Due to the time-sensitive nature of the review and the need to report the most up-to-date information for an ever-evolving situation, there were no restrictions on language, information sources utilised, publication status, and types of sources of evidence. The AACODS checklist was used to appraise each source of evidence. Outcome measures Publication characteristics, country-specific data points, COVID-19 specific data, demographics of affected HCWs, and public health measures employed Results A total of 152,888 infections and 1413 deaths were reported. Infections were mainly in women (71.6%) and nurses (38.6%), but deaths were mainly in men (70.8%) and doctors (51.4%). Limited data suggested that general practitioners and mental health nurses were the highest risk specialities for deaths. There were 37.17 deaths reported per 100 infections for healthcare workers aged over 70. Europe had the highest absolute numbers of reported infections (119628) and deaths (712), but the Eastern Mediterranean region had the highest number of reported deaths per 100 infections (5.7). Conclusions HCW COVID-19 infections and deaths follow that of the general world population. The reasons for gender and speciality differences require further exploration, as do the low rates reported from Africa and India. Although physicians working in certain specialities may be considered high-risk due to exposure to oronasal secretions, the risk to other specialities must not be underestimated. Elderly HCWs may require assigning to less risky settings such as telemedicine, or administrative positions. Our pragmatic approach provides general trends, and highlights the need for universal guidelines for testing and reporting of infections in HCWs. Summary Box What is already known on this topic In China, studies documented over 3,300 confirmed cases of infected healthcare workers in early March. In the United States, as high as 19% of patients had been identified as healthcare workers. There are no studies that perform a global examination of COVID-19 infections and deaths in the health workforce. What this study adds To our knowledge, this is the first study assessing the number of healthcare workers who have been infected with or died from COVID-19 globally. The data from our study suggest that although infections were mainly in women and nurses, COVID-19 related deaths were mainly in men and doctors; in addition, our study found that Europe had the highest numbers of infection and death, but the lowest case-fatality-rate, while the Eastern Mediterranean had the highest case-fatality-rate.
You are sitting in a busy paediatric outpatient clinic. Your patient is a 12-year-old girl who describes tight band-like headaches occurring daily affecting her school attendance and general mood for the past 8 months. Paracetamol and ibuprofen do not relieve her symptoms. Her GP prescribed Pizotifen, which made her tired and did not relieve the headache. After taking a detailed history and performing a thorough clinical examination, you make a diagnosis of tension-type headaches (TTH). The patient’s mother is keen to explore alternative and complementary therapies (ACTs).
In children with TTH (population), do ACTs (intervention) improve symptoms (outcome)?
MEDLINE (1946–present via PubMed), Embase (1974–present via Ovid) and the Cochrane Library were all searched. Search terms were (Alternative Medicine OR Complementary Medicine) AND (Headache NOT Migraine) AND (Infant OR Child OR Adolescent). MEDLINE turned over 362 records, Embase turned over 131 records and Cochrane turned over 3 records. A further search including keyword ‘Migraine’ was performed in order to screen for records previously eliminated but still containing data for TTH.
Inclusion criteria: age 0–18 years, English language, randomised controlled trials (RCTs)/systematic reviews/pragmatic clinical trials. RCTs were excluded if already analysed by an included systematic review, or if both TTH and migraines were included in the study group but TTH-specific data were not available. …
Coronavirus disease 2019 (COVID-19) has proved to be a severe global public health threat, causing high infection rates and mortality worldwide. Burundi was not spared the adverse health outcomes of COVID-19. Although Burundi’s initial response to the COVID-19 pandemic was criticized, hope arose in June 2020 when the new government instituted a plan to slow virus transmission that included public health campaigns, international travel restrictions, and mass testing, all of which proved effective. Burundi has faced many challenges in containing the virus, the first of which was the lack of initial preparedness and appropriate response to COVID-19. This was exacerbated by factors including shortages of personal protective equipment (PPE), limited numbers of life-saving ventilators (around 12 ventilators as of April 2020), and the presence of only one COVID-19 testing center with less than ten technicians in July 2020. Moreover, as Burundi is amongst the poorest countries in the world, some citizens were unable to access necessities such as water and soap, required for compliance with government recommendations regarding hygiene. Interestingly, Burundi did not implement a nationwide lockdown, allowing mass gatherings and public services to continue as usual due to a firm belief in God’s protection. As the daily confirmed cases have tripled since December 2020, Burundi must prepare itself for the threat of a new wave. Establishing precautionary measures to contain the virus and strengthening the health surveillance system in Burundi would significantly positively impact the prevention and management of COVID-19.
ABSTRACT Loss of functional RAB18 causes the autosomal recessive condition Warburg Micro syndrome. To better understand this disease, we used proximity biotinylation in HEK293 and HeLa cells to generate an inventory of potential RAB18 effectors. In HeLa cells, we expressed BirA*-RAB18 in cells in which RAB18-guanine nucleotide exchange factor (GEF) activity was disrupted with CRISPR. We found that most RAB18-interactions are regulated independently by its different GEFs; the binary RAB3GAP1-RAB3GAP2 complex and the TRAPPC9-containing TRAPPII complex. RAB3GAP-dependent RAB18 interactions included a group of microtubule-interacting/membrane shaping proteins, a group of proteins involved in membrane tethering and docking, and a group of lipid-modifying/lipid transport proteins. We demonstrate that GEF-dependent Rab-interactions are highly amenable to interrogation by proximity biotinylation. Further, we provide confirmatory evidence for several of the interactors (SPG20/SPART, SEC22A and TMCO4) as well as functional evidence supporting a role for RAB18 in modulating the close apposition of membranes and in cholesterol mobilization. SUMMARY STATEMENT We used proximity biotinylation together with guanine nucleotide exchange factor (GEF)-null cell lines to discriminate functional RAB18-interactions. We anticipate that this approach will be broadly applicable in small GTPase research.
ABSTRACT Loss of functional RAB18 causes the autosomal recessive condition Warburg Micro syndrome. To better understand this disease, we used proximity biotinylation to generate an inventory of potential RAB18 effectors. A restricted set of 28 RAB18-interactions were dependent on the binary RAB3GAP1-RAB3GAP2 RAB18-guanine nucleotide exchange factor (GEF) complex. 12 of these 28 interactions are supported by prior reports and we have directly validated novel interactions with SEC22A, TMCO4 and INPP5B. Consistent with a role for RAB18 in regulating membrane contact sites (MCSs), interactors included groups of microtubule/membrane-remodelling proteins, membrane-tethering and docking proteins, and lipid-modifying/transporting proteins. Two of the putative interactors, EBP and OSBPL2/ORP2, have sterol substrates. EBP (emopamil binding protein) is a Δ8-Δ7 sterol isomerase and OSBPL2/ORP2 is a lipid transport protein. This prompted us to investigate a role for RAB18 in cholesterol biosynthesis. We find that the cholesterol precursor and EBP-product lathosterol accumulates in both RAB18-null HeLa cells and RAB3GAP1-null fibroblasts derived from an affected individual. Further, de novo cholesterol biosynthesis is impaired in cells in which RAB18 is absent or dysregulated. Our data demonstrate that GEF-dependent Rab-interactions are highly amenable to interrogation by proximity biotinylation and may suggest that Micro syndrome is a cholesterol biosynthesis disorder.
Loss of functional RAB18 causes the autosomal recessive condition Warburg Micro syndrome. To better understand this disease, we used proximity biotinylation to generate an inventory of potential RAB18 effectors. A restricted set of 28 RAB18 interactions were dependent on the binary RAB3GAP1-RAB3GAP2 RAB18-guanine nucleotide exchange factor complex. Twelve of these 28 interactions are supported by prior reports, and we have directly validated novel interactions with SEC22A, TMCO4, and INPP5B. Consistent with a role for RAB18 in regulating membrane contact sites, interactors included groups of microtubule/membrane-remodeling proteins, membrane-tethering and docking proteins, and lipid-modifying/transporting proteins. Two of the putative interactors, EBP and OSBPL2/ORP2, have sterol substrates. EBP is a Δ8-Δ7 sterol isomerase, and ORP2 is a lipid transport protein. This prompted us to investigate a role for RAB18 in cholesterol biosynthesis. We found that the cholesterol precursor and EBP-product lathosterol accumulates in both RAB18-null HeLa cells and RAB3GAP1-null fibroblasts derived from an affected individual. Furthermore, de novo cholesterol biosynthesis is impaired in cells in which RAB18 is absent or dysregulated or in which ORP2 expression is disrupted. Our data demonstrate that guanine nucleotide exchange factor-dependent Rab interactions are highly amenable to interrogation by proximity biotinylation and may suggest that Micro syndrome is a cholesterol biosynthesis disorder.
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