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1.
Trends Biochem Sci ; 45(3): 228-243, 2020 03.
Article in English | MEDLINE | ID: mdl-31473074

ABSTRACT

Hundreds of metabolic enzymes work together smoothly in a cell. These enzymes are highly specific. Nevertheless, under physiological conditions, many perform side-reactions at low rates, producing potentially toxic side-products. An increasing number of metabolite repair enzymes are being discovered that serve to eliminate these noncanonical metabolites. Some of these enzymes are extraordinarily conserved, and their deficiency can lead to diseases in humans or embryonic lethality in mice, indicating their central role in cellular metabolism. We discuss how metabolite repair enzymes eliminate glycolytic side-products and prevent negative interference within and beyond this core metabolic pathway. Extrapolating from the number of metabolite repair enzymes involved in glycolysis, hundreds more likely remain to be discovered that protect a wide range of metabolic pathways.


Subject(s)
Enzymes/metabolism , Animals , Glycolysis , Humans , Mice
2.
Am J Hum Genet ; 108(6): 1151-1160, 2021 06 03.
Article in English | MEDLINE | ID: mdl-33979636

ABSTRACT

We describe a genetic syndrome due to PGM2L1 deficiency. PGM2 and PGM2L1 make hexose-bisphosphates, like glucose-1,6-bisphosphate, which are indispensable cofactors for sugar phosphomutases. These enzymes form the hexose-1-phosphates crucial for NDP-sugars synthesis and ensuing glycosylation reactions. While PGM2 has a wide tissue distribution, PGM2L1 is highly expressed in the brain, accounting for the elevated concentrations of glucose-1,6-bisphosphate found there. Four individuals (three females and one male aged between 2 and 7.5 years) with bi-allelic inactivating mutations of PGM2L1 were identified by exome sequencing. All four had severe developmental and speech delay, dysmorphic facial features, ear anomalies, high arched palate, strabismus, hypotonia, and keratosis pilaris. Early obesity and seizures were present in three individuals. Analysis of the children's fibroblasts showed that glucose-1,6-bisphosphate and other sugar bisphosphates were markedly reduced but still present at concentrations able to stimulate phosphomutases maximally. Hence, the concentrations of NDP-sugars and glycosylation of the heavily glycosylated protein LAMP2 were normal. Consistent with this, serum transferrin was normally glycosylated in affected individuals. PGM2L1 deficiency does not appear to be a glycosylation defect, but the clinical features observed in this neurodevelopmental disorder point toward an important but still unknown role of glucose-1,6-bisphosphate or other sugar bisphosphates in brain metabolism.


Subject(s)
Glucose-6-Phosphate/analogs & derivatives , Mutation , Neurodevelopmental Disorders/pathology , Phosphotransferases/genetics , Alleles , Child , Child, Preschool , Female , Glucose-6-Phosphate/biosynthesis , Glycosylation , Humans , Male , Neurodevelopmental Disorders/genetics , Neurodevelopmental Disorders/metabolism , Pedigree
3.
Mol Genet Metab ; 141(3): 108144, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38277989

ABSTRACT

Glycogen storage disease type Ib (GSD Ib, biallelic variants in SLC37A4) is a rare disorder of glycogen metabolism complicated by neutropenia/neutrophil dysfunction. Since 2019, the SGLT2-inhibitor empagliflozin has provided a mechanism-based treatment option for the symptoms caused by neutropenia/neutrophil dysfunction (e.g. mucosal lesions, inflammatory bowel disease). Because of the rarity of GSD Ib, the published evidence on safety and efficacy of empagliflozin is still limited and does not allow to develop evidence-based guidelines. Here, an international group of experts provides 14 best practice consensus treatment recommendations based on expert practice and review of the published evidence. We recommend to start empagliflozin in all GSD Ib individuals with clinical or laboratory signs related to neutropenia/neutrophil dysfunction with a dose of 0.3-0.4 mg/kg/d given as a single dose in the morning. Treatment can be started in an outpatient setting. The dose should be adapted to the weight and in case of inadequate clinical treatment response or side effects. We strongly recommend to pause empagliflozin immediately in case of threatening dehydration and before planned longer surgeries. Discontinuation of G-CSF therapy should be attempted in all individuals. If available, 1,5-AG should be monitored. Individuals who have previously not tolerated starches should be encouraged to make a new attempt to introduce starch in their diet after initiation of empagliflozin treatment. We advise to monitor certain safety and efficacy parameters and recommend continuous, alternatively frequent glucose measurements during the introduction of empagliflozin. We provide specific recommendations for special circumstances like pregnancy and liver transplantation.


Subject(s)
Benzhydryl Compounds , Glucosides , Glycogen Storage Disease Type I , Neutropenia , Humans , Neutrophils/metabolism , Consensus , Glycogen Storage Disease Type I/complications , Glycogen Storage Disease Type I/drug therapy , Glycogen Storage Disease Type I/genetics , Neutropenia/drug therapy , Neutropenia/etiology , Monosaccharide Transport Proteins , Antiporters/metabolism
4.
Mol Genet Metab ; 142(2): 108486, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38733639

ABSTRACT

Empagliflozin has been successfully repurposed for treating neutropenia and neutrophil dysfunction in patients with glycogen storage disease type 1b (GSD 1b), however, data in infants are missing. We report on efficacy and safety of empagliflozin in infants with GSD 1b. This is an international retrospective case series on 21 GSD 1b infants treated with empagliflozin (total treatment time 20.6 years). Before starting empagliflozin (at a median age of 8.1 months with a median dose of 0.3 mg/kg/day) 12 patients had clinical signs and symptoms of neutrophil dysfunction. Six of these previously symptomatic patients had no further neutropenia/neutrophil dysfunction-associated findings on empagliflozin. Eight patients had no signs and symptoms of neutropenia/neutrophil dysfunction before start and during empagliflozin treatment. One previously asymptomatic individual with a horseshoe kidney developed a central line infection with pyelonephritis and urosepsis during empagliflozin treatment. Of the 10 patients who were treated with G-CSF before starting empagliflozin, this was stopped in four and decreased in another four. Eleven individuals were never treated with G-CSF. While in 17 patients glucose homeostasis remained stable on empagliflozin, four showed glucose homeostasis instability in the introductory phase. In 17 patients, no other side effects were reported, while genital (n = 2) or oral (n = 1) candidiasis and skin infection (n = 1) were reported in the remaining four. Empagliflozin had a good effect on neutropenia/neutrophil dysfunction-related signs and symptoms and a favourable safety profile in infants with GSD 1b and therefore qualifies for further exploration as first line treatment.


Subject(s)
Benzhydryl Compounds , Glucosides , Glycogen Storage Disease Type I , Neutropenia , Neutrophils , Humans , Glycogen Storage Disease Type I/drug therapy , Glycogen Storage Disease Type I/complications , Neutropenia/drug therapy , Male , Female , Infant , Benzhydryl Compounds/therapeutic use , Benzhydryl Compounds/administration & dosage , Retrospective Studies , Neutrophils/drug effects , Glucosides/therapeutic use , Glucosides/pharmacology , Glucosides/administration & dosage , Sodium-Glucose Transporter 2 Inhibitors/therapeutic use , Treatment Outcome , Granulocyte Colony-Stimulating Factor/therapeutic use
5.
Med Microbiol Immunol ; 213(1): 15, 2024 Jul 15.
Article in English | MEDLINE | ID: mdl-39008129

ABSTRACT

Chlamydiae are a large group of obligate endosymbionts of eukaryotes that includes the Chlamydiaceae family, comprising several animal pathogens. Among Chlamydiaceae, Chlamydia trachomatis causes widespread ocular and urogenital infections in humans. Like many bacterial pathogens, all Chlamydiae manipulate host cells by injecting them with type III secretion effector proteins. We previously characterized the C. trachomatis effector CteG, which localizes at the host cell Golgi and plasma membrane during distinct phases of the chlamydial infectious cycle. Here, we show that CteG is a Chlamydiaceae-specific effector with over 60 homologs phylogenetically categorized into two distinct clades (CteG I and CteG II) and exhibiting several inparalogs and outparalogs. Notably, cteG I homologs are syntenic to C. trachomatis cteG, whereas cteG II homologs are syntenic among themselves but not with C. trachomatis cteG. This indicates a complex evolution of cteG homologs, which is unique among C. trachomatis effectors, marked by numerous events of gene duplication and loss. Despite relatively modest sequence conservation, nearly all tested CteG I and CteG II proteins were identified as type III secretion substrates using Yersinia as a heterologous bacterial host. Moreover, most of the type III secreted CteG I and CteG II homologs were delivered by C. trachomatis into host cells, where they localized at the Golgi region and cell periphery. Overall, this provided insights into the evolution of bacterial effectors and revealed a Chlamydiaceae family of type III secreted proteins that underwent substantial divergence during evolution while conserving the capacity to localize at specific host cell compartments.


Subject(s)
Bacterial Proteins , Chlamydia trachomatis , Phylogeny , Type III Secretion Systems , Humans , Chlamydia trachomatis/genetics , Chlamydia trachomatis/metabolism , Bacterial Proteins/metabolism , Bacterial Proteins/genetics , Type III Secretion Systems/metabolism , Type III Secretion Systems/genetics , Virulence Factors/metabolism , Virulence Factors/genetics , HeLa Cells , Yersinia/genetics , Yersinia/metabolism , Protein Transport , Host-Pathogen Interactions , Evolution, Molecular , Chlamydiaceae/genetics , Chlamydiaceae/metabolism , Chlamydiaceae/classification
6.
Brain ; 146(7): 2672-2693, 2023 07 03.
Article in English | MEDLINE | ID: mdl-36848323

ABSTRACT

Spinal cord injury (SCI) is an as yet untreatable neuropathology that causes severe dysfunction and disability. Cell-based therapies hold neuroregenerative and neuroprotective potential, but, although being studied in SCI patients for more than two decades, long-term efficacy and safety remain unproven, and which cell types result in higher neurological and functional recovery remains under debate. In a comprehensive scoping review of 142 reports and registries of SCI cell-based clinical trials, we addressed the current therapeutical trends and critically analysed the strengths and limitations of the studies. Schwann cells, olfactory ensheathing cells (OECs), macrophages and various types of stem cells have been tested, as well as combinations of these and other cells. A comparative analysis between the reported outcomes of each cell type was performed, according to gold-standard efficacy outcome measures like the ASIA impairment scale, motor and sensory scores. Most of the trials were in the early phases of clinical development (phase I/II), involved patients with complete chronic injuries of traumatic aetiology and did not display a randomized comparative control arm. Bone marrow stem cells and OECs were the most commonly tested cells, while open surgery and injection were the main methods of delivering cells into the spinal cord or submeningeal spaces. Transplantation of support cells, such as OECs and Schwann cells, resulted in the highest ASIA Impairment Scale (AIS) grade conversion rates (improvements in ∼40% of transplanted patients), which surpassed the spontaneous improvement rate expected for complete chronic SCI patients within 1 year post-injury (5-20%). Some stem cells, such as peripheral blood-isolated and neural stem cells, offer potential for improving patient recovery. Complementary treatments, particularly post-transplantation rehabilitation regimes, may contribute highly to neurological and functional recovery. However, unbiased comparisons between the tested therapies are difficult to draw, given the great heterogeneity of the design and outcome measures used in the SCI cell-based clinical trials and how these are reported. It is therefore crucial to standardize these trials when aiming for higher value clinical evidence-based conclusions.


Subject(s)
Nervous System Diseases , Spinal Cord Injuries , Humans , Cell- and Tissue-Based Therapy , Recovery of Function , Spinal Cord , Clinical Trials as Topic
7.
Cell Mol Life Sci ; 80(9): 259, 2023 Aug 18.
Article in English | MEDLINE | ID: mdl-37594549

ABSTRACT

Neutropenia and neutrophil dysfunction in glycogen storage disease type 1b (GSD1b) and severe congenital neutropenia type 4 (SCN4), associated with deficiencies of the glucose-6-phosphate transporter (G6PT/SLC37A4) and the phosphatase G6PC3, respectively, are the result of the accumulation of 1,5-anhydroglucitol-6-phosphate in neutrophils. This is an inhibitor of hexokinase made from 1,5-anhydroglucitol (1,5-AG), an abundant polyol in blood. 1,5-AG is presumed to be reabsorbed in the kidney by a sodium-dependent-transporter of uncertain identity, possibly SGLT4/SLC5A9 or SGLT5/SLC5A10. Lowering blood 1,5-AG with an SGLT2-inhibitor greatly improved neutrophil counts and function in G6PC3-deficient and GSD1b patients. Yet, this effect is most likely mediated indirectly, through the inhibition of the renal 1,5-AG transporter by glucose, when its concentration rises in the renal tubule following inhibition of SGLT2. To identify the 1,5-AG transporter, both human and mouse SGLT4 and SGLT5 were expressed in HEK293T cells and transport measurements were performed with radiolabelled compounds. We found that SGLT5 is a better carrier for 1,5-AG than for mannose, while the opposite is true for human SGLT4. Heterozygous variants in SGLT5, associated with a low level of blood 1,5-AG in humans cause a 50-100% reduction in 1,5-AG transport activity tested in model cell lines, indicating that SGLT5 is the predominant kidney 1,5-AG transporter. These and other findings led to the conclusion that (1) SGLT5 is the main renal transporter of 1,5-AG; (2) frequent heterozygous mutations (allelic frequency > 1%) in SGLT5 lower blood 1,5-AG, favourably influencing neutropenia in G6PC3 or G6PT deficiency; (3) the effect of SGLT2-inhibitors on blood 1,5-AG level is largely indirect; (4) specific SGLT5-inhibitors would be more efficient to treat these neutropenias than SGLT2-inhibitors.


Subject(s)
Neutropenia , Animals , Humans , Mice , Antiporters , HEK293 Cells , Kidney , Membrane Transport Proteins , Monosaccharide Transport Proteins/genetics , Neutropenia/genetics , Sodium-Glucose Transporter 2/genetics
8.
Curr Issues Mol Biol ; 45(9): 7617-7629, 2023 Sep 19.
Article in English | MEDLINE | ID: mdl-37754263

ABSTRACT

Toxicological studies on medicinal plants are essential to ensure their safety and effectiveness in treating various diseases. Despite the species Chrysobalanus icaco L. being popularly used in the treatment of several diseases due to the pharmacological properties of its bioactive compounds, there are few studies in the literature regarding its toxicity regarding reproduction. Therefore, the purpose of this study was to assess the potential embryotoxic and teratogenic effects of the aqueous extract of C. icaco leaves (AECi) on Wistar rats. Animals were given AECi at doses of 100, 200, and 400 mg/kg during the pre-implantation and organogenesis periods. Data were analyzed using ANOVA followed by Tukey's test and Kruskal-Wallis. Pregnant rats treated during the pre-implantation period showed no signs of reproductive toxicity. Rats that received AECi at 100, 200, and 400 mg/kg during organogenesis did not exhibit any signs of maternal systemic toxicity or significant differences in gestational and embryotoxic parameters. Some skeletal changes were observed in the treated groups. Therefore, it can be suggested that AECi at doses of 100, 200, and 400 mg/kg is safe for treated animals and does not induce reproductive toxicity under the experimental conditions applied, but it also caused low systemic toxicity.

9.
Mol Genet Metab ; 140(3): 107712, 2023 Nov.
Article in English | MEDLINE | ID: mdl-38353183

ABSTRACT

Glycogen storage disease type Ib (GSD1b) and G6PC3-deficiency are rare autosomal recessive diseases caused by inactivating mutations in SLC37A4 (coding for G6PT) and G6PC3, respectively. Both diseases are characterized by neutropenia and neutrophil dysfunction due to the intracellular accumulation of 1,5-anhydroglucitol-6-phosphate (1,5-AG6P), a potent inhibitor of hexokinases. We recently showed that the use of SGLT2 inhibitor therapy to reduce tubular reabsorption of its precursor, 1,5-anhydroglucitol (1,5-AG), a glucose analog present in blood, successfully restored the neutropenia and neutrophil function in G6PC3-deficient and GSD1b patients. The intra-individual variability of response to the treatment and the need to adjust the dose during treatment, especially in pediatric populations, can only be efficiently optimized if the concentration of 1,5-AG in blood is monitored during treatment, together with the patients' clinical signs and symptoms. Monitoring the 1,5-AG levels would be greatly simplified if it could be performed on dry blood spots (DBS) which are easy to collect, store and transport. The challenge is to know if a suitable method can be developed to perform accurate and reproducible assays for 1,5-AG using DBS. Here, we describe and validate an assay that quantifies 1,5-AG in DBS using isotopic dilution quantitation by LC-MS/MS that should greatly facilitate patients' follow-up. 1,5-AG levels measured in plasma and DBS give comparable values. This assay was used to monitor the levels of 1,5-AG in DBS from 3 G6PC3-deficient and 6 GSD1b patients during treatment with SGLT2 inhibitors. We recommend this approach to verify the adequate therapeutical response and compliance to the treatment in G6PC3-deficient and GSD1b patients treated with SGLT2 inhibitors.


Subject(s)
Deoxyglucose , Glycogen Storage Disease Type I , Neutropenia , Sodium-Glucose Transporter 2 Inhibitors , Child , Humans , Chromatography, Liquid , Tandem Mass Spectrometry , Glycogen Storage Disease Type I/drug therapy , Glycogen Storage Disease Type I/genetics , Glycogen Storage Disease Type I/complications , Neutropenia/genetics , Glucose-6-Phosphatase/genetics , Glucose-6-Phosphatase/metabolism , Phosphoric Monoester Hydrolases , Monosaccharide Transport Proteins , Antiporters
10.
Cell Mol Life Sci ; 79(8): 421, 2022 Jul 14.
Article in English | MEDLINE | ID: mdl-35834009

ABSTRACT

Transaminases play key roles in central metabolism, transferring the amino group from a donor substrate to an acceptor. These enzymes can often act, with low efficiency, on compounds different from the preferred substrates. To understand what might have shaped the substrate specificity of this class of enzymes, we examined the reactivity of six human cytosolic transaminases towards amino acids whose main degradative pathways do not include any transamination. We also tested whether sugars and sugar phosphates could serve as alternative amino group acceptors for these cytosolic enzymes. Each of the six aminotransferases reacted appreciably with at least three of the alternative amino acid substrates in vitro, albeit at usually feeble rates. Reactions with L-Thr, L-Arg, L-Lys and L-Asn were consistently very slow-a bias explained in part by the structural differences between these amino acids and the preferred substrates of the transaminases. On the other hand, L-His and L-Trp reacted more efficiently, particularly with GTK (glutamine transaminase K; also known as KYAT1). This points towards a role of GTK in the salvage of L-Trp (in cooperation with ω-amidase and possibly with the cytosolic malate dehydrogenase, MDH1, which efficiently reduced the product of L-Trp transamination). Finally, the transaminases were extremely ineffective at utilizing sugars and sugar derivatives, with the exception of the glycolytic intermediate dihydroxyacetone phosphate, which was slowly but appreciably transaminated by some of the enzymes to yield serinol phosphate. Evidence for the formation of this compound in a human cell line was also obtained. We discuss the biological and evolutionary implications of our results.


Subject(s)
Amino Acids , Transaminases , Cytosol/metabolism , Humans , Kinetics , Substrate Specificity , Sugars , Transaminases/metabolism
11.
J Biol Chem ; 296: 100699, 2021.
Article in English | MEDLINE | ID: mdl-33895133

ABSTRACT

N-acetylneuraminate (Neu5Ac), an abundant sugar present in glycans in vertebrates and some bacteria, can be used as an energy source by several prokaryotes, including Escherichia coli. In solution, more than 99% of Neu5Ac is in cyclic form (≈92% beta-anomer and ≈7% alpha-anomer), whereas <0.5% is in the open form. The aldolase that initiates Neu5Ac metabolism in E. coli, NanA, has been reported to act on the alpha-anomer. Surprisingly, when we performed this reaction at pH 6 to minimize spontaneous anomerization, we found NanA and its human homolog NPL preferentially metabolize the open form of this substrate. We tested whether the E. coli Neu5Ac anomerase NanM could promote turnover, finding it stimulated the utilization of both beta and alpha-anomers by NanA in vitro. However, NanM is localized in the periplasmic space and cannot facilitate Neu5Ac metabolism by NanA in the cytoplasm in vivo. We discovered that YhcH, a cytoplasmic protein encoded by many Neu5Ac catabolic operons and belonging to a protein family of unknown function (DUF386), also facilitated Neu5Ac utilization by NanA and NPL and displayed Neu5Ac anomerase activity in vitro. YhcH contains Zn, and its accelerating effect on the aldolase reaction was inhibited by metal chelators. Remarkably, several transition metals accelerated Neu5Ac anomerization in the absence of enzyme. Experiments with E. coli mutants indicated that YhcH expression provides a selective advantage for growth on Neu5Ac. In conclusion, YhcH plays the unprecedented role of providing an aldolase with the preferred unstable open form of its substrate.


Subject(s)
Fructose-Bisphosphate Aldolase/metabolism , N-Acetylneuraminic Acid/metabolism , Escherichia coli/enzymology , Fructose-Bisphosphate Aldolase/chemistry , Models, Molecular , N-Acetylneuraminic Acid/chemistry , Periplasm/metabolism , Protein Conformation , Protein Transport , Stereoisomerism
12.
Blood ; 136(9): 1033-1043, 2020 08 27.
Article in English | MEDLINE | ID: mdl-32294159

ABSTRACT

Neutropenia and neutrophil dysfunction cause serious infections and inflammatory bowel disease in glycogen storage disease type Ib (GSD-Ib). Our discovery that accumulating 1,5-anhydroglucitol-6-phosphate (1,5AG6P) caused neutropenia in a glucose-6-phosphatase 3 (G6PC3)-deficient mouse model and in 2 rare diseases (GSD-Ib and G6PC3 deficiency) led us to repurpose the widely used antidiabetic drug empagliflozin, an inhibitor of the renal glucose cotransporter sodium glucose cotransporter 2 (SGLT2). Off-label use of empagliflozin in 4 GSD-Ib patients with incomplete response to granulocyte colony-stimulating factor (GCSF) treatment decreased serum 1,5AG and neutrophil 1,5AG6P levels within 1 month. Clinically, symptoms of frequent infections, mucosal lesions, and inflammatory bowel disease resolved, and no symptomatic hypoglycemia was observed. GCSF could be discontinued in 2 patients and tapered by 57% and 81%, respectively, in the other 2. The fluctuating neutrophil numbers in all patients were increased and stabilized. We further demonstrated improved neutrophil function: normal oxidative burst (in 3 of 3 patients tested), corrected protein glycosylation (2 of 2), and normal neutrophil chemotaxis (1 of 1), and bactericidal activity (1 of 1) under treatment. In summary, the glucose-lowering SGLT2 inhibitor empagliflozin, used for type 2 diabetes, was successfully repurposed for treating neutropenia and neutrophil dysfunction in the rare inherited metabolic disorder GSD-Ib without causing symptomatic hypoglycemia. We ascribe this to an improvement in neutrophil function resulting from the reduction of the intracellular concentration of 1,5AG6P.


Subject(s)
Benzhydryl Compounds/therapeutic use , Glucosides/therapeutic use , Glycogen Storage Disease Type I/complications , Hexosephosphates/blood , Neutropenia/drug therapy , Neutrophils/pathology , Sodium-Glucose Transporter 2 Inhibitors/therapeutic use , Benzhydryl Compounds/adverse effects , Blood Glucose/analysis , Chemotaxis, Leukocyte/drug effects , Child, Preschool , Drug Repositioning , Drug Resistance , Female , Glucosides/adverse effects , Glycogen Storage Disease Type I/blood , Glycogen Storage Disease Type I/immunology , Granulocyte Colony-Stimulating Factor/therapeutic use , Granulocytes/chemistry , Humans , Infant, Newborn , Lysosomal-Associated Membrane Protein 2/blood , Male , Neutropenia/blood , Off-Label Use , Respiratory Burst/drug effects , Sodium-Glucose Transporter 2 Inhibitors/adverse effects , Young Adult
13.
J Inherit Metab Dis ; 45(4): 759-768, 2022 07.
Article in English | MEDLINE | ID: mdl-35506446

ABSTRACT

Neutropenia and neutrophil dysfunction found in deficiencies in G6PC3 and in the glucose-6-phosphate transporter (G6PT/SLC37A4) are due to accumulation of 1,5-anhydroglucitol-6-phosphate (1,5-AG6P), an inhibitor of hexokinase made from 1,5-anhydroglucitol (1,5-AG), an abundant polyol present in blood. Lowering blood 1,5-AG with an SGLT2 inhibitor greatly improved neutrophil counts and function in G6PC3-deficient mice and in patients with G6PT-deficiency. We evaluate this treatment in two G6PC3-deficient children. While neutropenia was severe in one child (PT1), which was dependent on granulocyte cololony-stimulating factor (GCSF), it was significantly milder in the other one (PT2), which had low blood 1,5-AG levels and only required GCSF during severe infections. Treatment with the SGLT2-inhibitor empagliflozin decreased 1,5-AG in blood and 1,5-AG6P in neutrophils and improved (PT1) or normalized (PT2) neutrophil counts, allowing to stop GCSF. On empagliflozin, both children remained infection-free (>1 year - PT2; >2 years - PT1) and no side effects were reported. Remarkably, sequencing of SGLT5, the gene encoding the putative renal transporter for 1,5-AG, disclosed a rare heterozygous missense mutation in PT2, replacing the extremely conserved Arg401 by a histidine. The higher urinary clearance of 1,5-AG explains the more benign neutropenia and the outstanding response to empagliflozin treatment found in this child. Our data shows that SGLT2 inhibitors are an excellent alternative to treat the neutropenia present in G6PC3-deficiency.


Subject(s)
Glycogen Storage Disease Type I , Neutropenia , Sodium-Glucose Transport Proteins/metabolism , Animals , Antiporters/genetics , Benzhydryl Compounds , Glucose-6-Phosphatase/genetics , Glucose-6-Phosphatase/metabolism , Glucosides/therapeutic use , Glycogen Storage Disease Type I/drug therapy , Glycogen Storage Disease Type I/genetics , Humans , Mice , Monosaccharide Transport Proteins/genetics , Mutation , Neutropenia/drug therapy , Neutropenia/genetics , Phosphoric Monoester Hydrolases/genetics
14.
J Water Health ; 20(8): 1188-1196, 2022 Aug.
Article in English | MEDLINE | ID: mdl-36044188

ABSTRACT

Giardia duodenalis is responsible for several waterborne gastrointestinal outbreaks worldwide. In addition to limitations presented by the main disinfection methods, assessing the inactivation efficiency of cysts after the treatment also poses challenges. Thus, this study aimed to use the 5-carboxyfluorescein diacetate acetoxymethyl ester (CFDA-AM) staining protocol to evaluate the viability of G. duodenalis cysts inactivated by different UV and chlorination doses and boiling times. Under epifluorescent microscopy, metabolically active cysts that presented green fluorescence were considered viable. In contrast, when no green fluorescence could be observed, organisms were considered non-viable. Although statistical analysis revealed that increasing the UV dose did not significantly decrease the percentage of viable cysts, the fluorescence signal intensity decreased considerably when the cysts were irradiated with a dose equal to or greater than 80 mJ cm-2. Regarding chlorination and boiling treatments, this study demonstrated that no cyst showed fluorescence at the lowest NaClO concentration (0.5 mg/L) and in the shortest boiling time (2 min). Despite some limitations regarding the use of metabolic activity as a viability marker, this methodology is rapid, easy to run and cost-effective. Thus, we conclude that the CFDA-AM staining protocol has the potential to be used to assess Giardia cyst inactivation, although further research is required.


Subject(s)
Cryptosporidium , Cysts , Giardia lamblia , Animals , Chlorine/pharmacology , Esters/pharmacology , Fluoresceins , Giardia , Oocysts , Staining and Labeling
15.
BMC Health Serv Res ; 22(1): 659, 2022 May 16.
Article in English | MEDLINE | ID: mdl-35578239

ABSTRACT

BACKGROUND: Telemedicine has grown significantly in recent years, mainly during the COVID-19 pandemic, and there has been a growing body of literature on the subject. Another topic that merits increased attention is differences in patient and family experience between telehealth and in-person visits. To our team's knowledge, this is the first study evaluating pediatric and obstetrics outpatients experience with telemedicine and in-person visit types in an academic maternal and children's hospital, and its correlation with geographic distance from the medical center throughout 2020, during the COVID-19 crisis. METHODS: We aim to evaluate and compare patients' telemedicine and in-person experience for ambulatory encounters based on survey data throughout 2020, during the COVID-19 pandemic, with particular focus on the influence of distance of the patient's home address from the medical facility. A total of 9,322 patient experience surveys from ambulatory encounters (6,362 in-person and 2,960 telemedicine), in a maternal and children's hospital during 2020 were included in this study. The percentage of patients who scored the question "Likelihood to recommend practice" with a maximum 5/5 (top box) score was used to evaluate patient experience. The k-means model was used to create distance clusters, and statistical t-tests were conducted to compare mean distances and Top Box values between telemedicine and in-person models. Logistic regression analysis was used to evaluate the correlation between Top Box scores and patients' distance to the hospital. RESULTS: Top Box likelihood to recommend percentages for in-person and telemedicine were comparable (in-person = 81.21%, telemedicine = 81.70%, p-value = 0.5624). Mean distance from the hospital was greater for telemedicine compared to in-person patients (in-person = 48.89 miles, telemedicine = 61.23 miles, p-value < 0.01). Patients who live farther displayed higher satisfaction scores regardless of the visit type (p-value < 0.01). CONCLUSIONS: There is a direct relationship between the family experience and the distance from the considered medical center, during year 2020, i.e., patients who live farther from the hospital record higher Top Box proportion for "Likelihood to Recommend" than patients who live closer to the medical center, regardless of the approach, in-person or telemedicine.


Subject(s)
COVID-19 , Obstetrics , Telemedicine , COVID-19/epidemiology , Child , Female , Humans , Outpatients , Pandemics , Patient Satisfaction , Pregnancy
16.
BMC Health Serv Res ; 22(1): 49, 2022 Jan 10.
Article in English | MEDLINE | ID: mdl-35012514

ABSTRACT

BACKGROUND: Health care is a complex economic and social system, which combines market elements and public and social interest. This combination in Brazil, like systems in China and United States of America, is operationalized through the public and private system. The sector represents approximately 9% of the country's GDP, of which 56% is privately sourced and 44% is of public origin. In the private sector includes a structure with 711 private health institutions, 47 million beneficiaries and revenues of US$30 billion a year. METHODS: Therefore, this research describes and analyzes the complementarity of Private Health before the Brazilian Unified Health System, highlighting its main characteristics, scenarios, and trends in the face of the health system and the Brazilian market. This descriptive and exploratory research uses secondary data from various sources, submitted to quantitative data analysis methods. The object of the research is the history of private health in Brazil and its main actors. RESULTS: The data are organized into three groups, each with its approach of collection and analysis. Thus, it is perceived as the notorious growth of large operators, to the detriment of operators with a lower concentration of beneficiaries; the increasing concentration of the market through mergers and acquisitions promoted by large publicly traded corporations, especially in regions with a lower rate of private health coverage; and the growth of the sector through business plans, whose central characteristic is the dependence on the country's employability rate. CONCLUSIONS: It is possible to perceive an intense trend of concentration of Brazilian private health in large institutions that have capitalized and have a great appetite for growth through mergers and acquisitions, whether from smaller operators or health institutions that integrate their health networks, following complementary health models already consolidated in countries such as China, and the United States of America, among others. This concentration projects a market with fewer options and competitiveness, reduction in transaction costs and increase the operational effectiveness of health care.


Subject(s)
Private Sector , Public Sector , Brazil , Delivery of Health Care , Government Programs , Humans
17.
Proc Natl Acad Sci U S A ; 116(4): 1241-1250, 2019 01 22.
Article in English | MEDLINE | ID: mdl-30626647

ABSTRACT

Neutropenia represents an important problem in patients with genetic deficiency in either the glucose-6-phosphate transporter of the endoplasmic reticulum (G6PT/SLC37A4) or G6PC3, an endoplasmic reticulum phosphatase homologous to glucose-6-phosphatase. While affected granulocytes show reduced glucose utilization, the underlying mechanism is unknown and causal therapies are lacking. Using a combination of enzymological, cell-culture, and in vivo approaches, we demonstrate that G6PT and G6PC3 collaborate to destroy 1,5-anhydroglucitol-6-phosphate (1,5AG6P), a close structural analog of glucose-6-phosphate and an inhibitor of low-KM hexokinases, which catalyze the first step in glycolysis in most tissues. We show that 1,5AG6P is made by phosphorylation of 1,5-anhydroglucitol, a compound normally present in human plasma, by side activities of ADP-glucokinase and low-KM hexokinases. Granulocytes from patients deficient in G6PC3 or G6PT accumulate 1,5AG6P to concentrations (∼3 mM) that strongly inhibit hexokinase activity. In a model of G6PC3-deficient mouse neutrophils, physiological concentrations of 1,5-anhydroglucitol caused massive accumulation of 1,5AG6P, a decrease in glucose utilization, and cell death. Treating G6PC3-deficient mice with an inhibitor of the kidney glucose transporter SGLT2 to lower their blood level of 1,5-anhydroglucitol restored a normal neutrophil count, while administration of 1,5-anhydroglucitol had the opposite effect. In conclusion, we show that the neutropenia in patients with G6PC3 or G6PT mutations is a metabolite-repair deficiency, caused by a failure to eliminate the nonclassical metabolite 1,5AG6P.


Subject(s)
Antiporters/metabolism , Glucose-6-Phosphatase/metabolism , Glucose/metabolism , Monosaccharide Transport Proteins/metabolism , Neutropenia/metabolism , Phosphorylation/physiology , Animals , Cell Death/physiology , Cell Line , Endoplasmic Reticulum/metabolism , Female , HEK293 Cells , Humans , Male , Mice , Mice, Inbred C57BL , Neutrophils/metabolism , Rats, Wistar
18.
An Acad Bras Cienc ; 94(1): e20200940, 2022.
Article in English | MEDLINE | ID: mdl-35170628

ABSTRACT

Antioxidants present in many fruit residues can play an essential role in the prevention of diseases. The aim of this study was to determine nutritional and mineral composition, fatty acids profile, anti-nutrients, bioactive compounds, antioxidant activity and technological properties of flour from residues generated by umbu fruit processing. Nutritional composition showed high levels of dietary fiber, especially insoluble fiber (56.67%). The flour can be classified as a good source of calcium, phosphorus and magnesium, and an excellent source of iron, zinc and copper. Palmitic and stearic saturated fatty acids and oleic and linoleic unsaturated fatty acids were identified. No potentially toxic substances were detected. Significant values of ascorbic acid (44.78 mg/100g), carotenoids (463.73 µg/100g) and flavonoids (37.85 mg QE/100g) were found, as well as very high levels of phenolic compounds (20357.26 mg GAE/100g). Strong antioxidant activity was detected in the flour by three methods (ABTS, DPPH and FRAP) demonstrating a linear positive correlation between phenolic content and antioxidant activity. The flour showed high absorption of water, oil, emulsifying capacity and emulsion stability presenting a great potential for use in foods, especially meat, bakery and dairy products. These results indicate promising prospects to full use of umbu as a functional ingredient.


Subject(s)
Anacardiaceae , Flour , Antioxidants , Flavonoids , Flour/analysis , Fruit
19.
Dysphagia ; 37(6): 1375-1385, 2022 12.
Article in English | MEDLINE | ID: mdl-35230536

ABSTRACT

In swallowing, the hyoid bone moves up and forward in response to the activation of suprahyoid muscles, opening the upper esophageal sphincter and aiding the airway protection mechanism. This displacement measure has been analyzed with ultrasound images because this method does not expose the patient to radiation, has a good cost-benefit ratio, and is safe for the patient. However, there is no consensus on the reliability of this ultrasound measure. The objective of this study was to analyze the reliability of measuring hyoid bone displacement amplitude in swallowing with ultrasound. The systematic review encompassed five databases (MEDLINE, Scopus, EMBASE, Web of Science, Cochrane Library) and gray literature. There was no limitation of language or year of publication. The search/selection/extraction methodology was conducted by two authors blindly and independently, and differences were solved by a third rater. Three studies met the eligibility criteria: two of them analyzed the reliability in non-dysphagic populations and the other, in dysphagic patients. The transducer was positioned in the submandibular region in all studies. The authors were not clear about the training time to acquire and analyze ultrasound images. The meta-analysis had an interrater reliability of 0.858 (95% CI: 0.744-0.924) and intrarater reliability of 0.968 (95% CI: 0.903-0.990). There was, however, heterogeneity of p = 0.005 for intrarater reliability. Despite good reliability, the heterogeneity reinforces the importance of training and protocol standardization for image acquisition and analysis.


Subject(s)
Deglutition Disorders , Hyoid Bone , Humans , Hyoid Bone/diagnostic imaging , Hyoid Bone/physiology , Reproducibility of Results , Deglutition/physiology , Deglutition Disorders/diagnostic imaging , Deglutition Disorders/etiology , Ultrasonography
20.
Ann Diagn Pathol ; 56: 151843, 2022 Feb.
Article in English | MEDLINE | ID: mdl-34717191

ABSTRACT

CUL2 plays a crucial role in proteolysis by preserving the balance between normal growth and uncontrolled proliferation. HSPA9 safeguards the integrity of protein interactions and supports cellular homeostasis. In carcinomas, HSPA9 and CUL2 appear to protect neoplastic cells from internal and external damage. In prostate tumors they are apparently associated with increased risk of unfavorable outcomes, but information remains scarce. In this study we evaluated CUL2 and HSPA9 expression in neoplastic and non-neoplastic prostate tissue and Gleason pattern 3 and 4 adenocarcinoma to identify associations with ISUP prognostic groups and postoperative disease progression. The records of 636 radical prostatectomy patients were reviewed retrospectively and microarrays were mounted with paraffin-embedded adenocarcinoma and non-neoplastic tissue. We evaluated the ability of HSPA9 and CUL2 to predict postoperative PSA outcomes, response to adjuvant/salvage therapy and systemic disease. HSPA9 and CUL2 were diffusely expressed. HSPA9 expression was associated with increased risk of high-grade adenocarcinoma, while HSPA9 and CUL2 were associated with biochemical failure after salvage therapy. In conclusion, HSPA9 and CUL2 were highly expressed in prostate tissue, especially in neoplastic cells. HSPA9 and CUL2-positive Gleason pattern 3 adenocarcinoma was more likely to be associated with Gleason pattern 4 or 5, while HSPA9 and CUL2-positive Gleason pattern 4 adenocarcinoma was less likely to belong to ISUP groups 1 and 2. Staining for HSPA9 and CUL2 can help identify patients at increased risk of recurrence after salvage therapy.


Subject(s)
Adenocarcinoma/metabolism , Cullin Proteins/metabolism , HSP70 Heat-Shock Proteins/metabolism , Mitochondrial Proteins/metabolism , Prostate/metabolism , Prostatic Neoplasms/metabolism , Adenocarcinoma/pathology , Adenocarcinoma/surgery , Humans , Immunohistochemistry , Male , Neoplasm Grading , Prostate/pathology , Prostate/surgery , Prostatectomy , Prostatic Neoplasms/pathology , Prostatic Neoplasms/surgery , Retrospective Studies
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