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1.
Article in English | MEDLINE | ID: mdl-38951991

ABSTRACT

Alveolar ridge resorption following tooth extraction poses significant challenges for future dental restorations. This study investigated the efficacy of fish scale-derived hydroxyapatite (FSHA) as a socket preservation graft material to maintain alveolar bone volume and architecture. FSHA was extracted from *Labeo rohita* fish scales and characterized using Fourier transform infrared (FTIR) analysis. In vitro, biocompatibility and osteogenic potential were assessed using Saos-2 human osteosarcoma cells. Cell viability, migration, and proliferation were evaluated using MTT and scratch assays. In vivo performance was assessed in a rat model, and FSHA was compared to a commercial xenograft (Osseograft) and ungrafted controls. Histological analysis was performed at 8-week post-implantation to quantify new bone formation. FTIR confirmed the purity and homogeneity of FSHA. In vitro, FSHA enhanced Saos-2 viability, migration, and proliferation compared to controls. In vivo, FSHA demonstrated superior bone regeneration compared to Osseograft and ungrafted sites, with balanced graft resorption and new bone formation. Histological analysis revealed an active incorporation of FSHA into new bone, with minimal gaps and ongoing remodeling. Approximately 50%-60% of FSHA was resorbed by 8 weeks, closely matching the rate of new bone deposition. FSHA stimulated more bone formation in the apical socket region than in coronal areas. In conclusion, FSHA is a promising biomaterial for alveolar ridge preservation, exhibiting excellent biocompatibility, osteogenic potential, and balanced resorption. Its ability to promote robust bone regeneration highlights its potential as an effective alternative to currently used graft materials in socket preservation procedures.

2.
Front Bioeng Biotechnol ; 12: 1357182, 2024.
Article in English | MEDLINE | ID: mdl-38983601

ABSTRACT

The number of lung transplantations is limited due to the shortage of donor lungs fulfilling the standard criteria. The ex vivo lung perfusion (EVLP) technique provides the ability of re-evaluating and potentially improving and treating marginal donor lungs. Accordingly, the technique has emerged as an essential tool to increase the much-needed donor lung pool. One of the major EVLP protocols, the Lund protocol, characterized by high pulmonary artery flow (100% of cardiac output [CO]), an open atrium, and a cellular perfusate, has demonstrated encouraging short-EVLP duration results. However, the potential of the longer EVLP duration of the protocol is yet to be investigated, a duration which is considered necessary to rescue more marginal donor lungs in future. This study aimed to achieve stable 8-h EVLP using an open-atrium cellular model with three different pulmonary artery flows in addition to determining the most optimal flow in terms of best lung performance, including lung electrolytes and least lung edema formation, perfusate and tissue inflammation, and histopathological changes, using the porcine model. EVLP was performed using a flow of either 40% (n = 6), 80% (n = 6), or 100% (n = 6) of CO. No flow rate demonstrated stable 8-h EVLP. Stable 2-h EVLP was observed in all three groups. Insignificant deterioration was observed in dynamic compliance, peak airway pressure, and oxygenation between the groups. Pulmonary vascular resistance increased significantly in the 40% group (p < .05). Electrolytes demonstrated an insignificant worsening trend with longer EVLP. Interleukin-8 (IL-8) in perfusate and tissue, wet-to-dry weight ratio, and histopathological changes after EVLP were insignificantly time dependent between the groups. This study demonstrated that stable 8-h EVLP was not feasible in an open-atrium cellular model regardless of the flow of 40%, 80%, or 100% of CO. No flow was superior in terms of lung performance, lung electrolytes changes, least lung edema formation, minimal IL-8 expression in perfusate and tissue, and histopathological changes.

4.
J Infect Dis ; 2024 Jul 09.
Article in English | MEDLINE | ID: mdl-38979599

ABSTRACT

BACKGROUND: The Dantu blood group variant protects against P. falciparum infections but its wider consequences have not been previously explored. Here, we investigate the impact of Dantu on susceptibility to bacteraemia. METHODS: We conducted a case-control study in children presenting with community-acquired bacteraemia to Kilifi County Hospital in Kenya between 1998 and 2010. We used logistic regression to test for associations between the Dantu marker SNP rs186873296 A>G and both all-cause and pathogen-specific bacteraemia under an additive model. We used date of admission as a proxy measure of malaria transmission intensity, given known differences in malaria prevalence over the course of the study. RESULTS: Dantu was associated with protection from all-cause bacteraemia (OR=0.81, p=0.014), the association being greatest in homozygotes (OR=0.30, p=0.013). This protection was shared across the major bacterial pathogens but, notably, was only significant during the era of high malaria-transmission pre-2003 (OR=0.79, p=0.023). CONCLUSIONS: Consistent with previous studies showing the indirect impact on bacteraemia risk of other malaria-associated red cell variants, our study also shows that Dantu is protective against bacteraemia via its effect on malaria risk. Dantu does not appear to be under balancing selection through an increased risk of bacterial infections.

5.
J Avian Med Surg ; 38(2): 83-90, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38980817

ABSTRACT

Renal disease is often identified as a cause of morbidity and mortality in avian patients. However, currently, early antemortem detection of renal disease in avian patients is difficult. Anatomical and physiological differences between mammals and birds mean the use of commonly employed diagnostic testing (ie, measurement of blood urea nitrogen [BUN] and serum creatinine, urinalysis, and ultrasonography) are either nondiagnostic or difficult to achieve. Symmetric dimethylarginine (SDMA) is considered a more sensitive marker for renal disease in humans, dogs, and cats. However, SDMA has not yet been assessed for diagnostic use in any psittacine species. In this study, we establish reference ranges for SDMA in both Hispaniolan Amazon parrots (Amazona ventralis, HAP) and Quaker parrots (Myiopsitta monachus, QP). Blood was collected from 23 Amazon parrots and 32 Quaker parrots maintained in research facilities. Measurement of SDMA through a commercially available immunoassay (IA-SDMA) as well as creatinine, BUN, uric acid, phosphorus, calcium, sodium, potassium, and chloride were determined through IDEXX Laboratories. Plasma SDMA concentrations ranged from 6 to 15 µg/dL and 3 to 15 µg/dL for the HAP and QP, respectively. Sex was a confounding factor for the QP population, but sex did not have a significant effect on SDMA for the HAP population. No significant correlations were identified between SDMA concentrations and other parameters in either psittacine species. Our results show proof of concept for the IA-SDMA and provide reference intervals for SDMA in HAP and QP. Further investigation is required to determine the validity of this assay and the predictive power of SDMA in the detection of renal impairment for parrots and other common companion birds.


Subject(s)
Arginine , Parrots , Animals , Reference Values , Male , Arginine/analogs & derivatives , Arginine/blood , Female , Parrots/blood , Amazona/blood , Biomarkers/blood
6.
J Avian Med Surg ; 38(2): 98-107, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38980819

ABSTRACT

The objective of this study was to establish the pharmacokinetics of a single oral dose of trazodone in the Hispaniolan Amazon parrot (Amazona ventralis). Trazodone is a selective serotonin antagonist and reuptake inhibitor used commonly in both human and veterinary medicine as an antidepressant behavioral modification medicine. A single oral dose of compounded trazodone hydrochloride solution (20 mg/mL) at 50 mg/kg was administered to a total of 7 healthy adult Hispaniolan Amazon parrots. The 7 healthy adult parrots ranged in age from 10 to 15 years and weighed 228 to 323g. Blood was collected at baseline (2 weeks before study) and at 1, 2, 4, 6, 10, and 14 hours post-drug administration. Plasma concentrations of both trazodone and its active metabolite m-chlorophenylpiperazine (mCPP) were measured via liquid chromatography tandem mass spectrometry. Noncompartmental pharmacokinetic analysis was completed. The half-life (t1/2) ± SD of trazodone for the Hispaniolan parrots was 1.89 ± 0.49 hours, and the t1/2 ± SD of mCPP metabolite was 1.9 ± 0.55 hours. Maximum serum drug concentrations, or Cmax (ng/mL), were 738.3 ± 285.3 for trazodone. Times to achieve Cmax (hours) for trazadone and the mCPP metabolite were 1 hour and 2 hours postdosing, respectively. While this study did not establish the behavioral effects of trazodone, no adverse side effects were observed throughout the 48-hour period following drug administration and blood collection. Our results indicate that the oral administration of a 50-mg/kg single dose of trazodone to Hispaniolan parrots may be considered a safe dose. Plasma concentrations are comparable to previously published values in humans, dogs, horses, and pigeons (Columba livia domestica) for up to 14 hours following dosing. This study indicates that further studies are needed to establish the pharmacodynamics and the efficacy of trazodone in the medical management of behavioral problems in psittacine species.


Subject(s)
Amazona , Trazodone , Animals , Trazodone/pharmacokinetics , Trazodone/administration & dosage , Trazodone/blood , Amazona/blood , Half-Life , Male , Area Under Curve , Selective Serotonin Reuptake Inhibitors/pharmacokinetics , Selective Serotonin Reuptake Inhibitors/administration & dosage , Selective Serotonin Reuptake Inhibitors/blood , Female , Administration, Oral
7.
bioRxiv ; 2024 Jun 10.
Article in English | MEDLINE | ID: mdl-38915729

ABSTRACT

The receptor tyrosine kinase EphA2 drives cancer malignancy by facilitating metastasis. EphA2 can be found in different self-assembly states: as a monomer, dimer, and oligomer. However, our understanding remains limited regarding which EphA2 state is responsible for driving pro-metastatic signaling. To address this limitation, we have developed SiMPull-POP, a single-molecule method for accurate quantification of membrane protein self-assembly. Our experiments revealed that a reduction of plasma membrane cholesterol strongly promoted EphA2 self-assembly. Indeed, low cholesterol caused a similar effect to the EphA2 ligand ephrinA1-Fc. These results indicate that cholesterol inhibits EphA2 assembly. Phosphorylation studies in different cell lines revealed that low cholesterol increased phospho-serine levels, the signature of oncogenic signaling. Investigation of the mechanism that cholesterol uses to inhibit the assembly and activity of EphA2 indicate an in-trans effect, where EphA2 is phosphorylated by protein kinase A downstream of beta-adrenergic receptor activity, which cholesterol also inhibits. Our study not only provides new mechanistic insights on EphA2 oncogenic function, but also suggests that cholesterol acts as a molecular safeguard mechanism that prevents uncontrolled self-assembly and activation of EphA2.

8.
Microbiol Spectr ; 12(7): e0410823, 2024 Jul 02.
Article in English | MEDLINE | ID: mdl-38832899

ABSTRACT

The rapid spread of antimicrobial resistance (AMR) is a threat to global health, and the nature of co-occurring antimicrobial resistance genes (ARGs) may cause collateral AMR effects once antimicrobial agents are used. Therefore, it is essential to identify which pairs of ARGs co-occur. Given the wealth of next-generation sequencing data available in public repositories, we have investigated the correlation between ARG abundances in a collection of 214,095 metagenomic data sets. Using more than 6.76∙108 read fragments aligned to acquired ARGs to infer pairwise correlation coefficients, we found that more ARGs correlated with each other in human and animal sampling origins than in soil and water environments. Furthermore, we argued that the correlations could serve as risk profiles of resistance co-occurring to critically important antimicrobials (CIAs). Using these profiles, we found evidence of several ARGs conferring resistance for CIAs being co-abundant, such as tetracycline ARGs correlating with most other forms of resistance. In conclusion, this study highlights the important ARG players indirectly involved in shaping the resistomes of various environments that can serve as monitoring targets in AMR surveillance programs. IMPORTANCE: Understanding the collateral effects happening in a resistome can reveal previously unknown links between antimicrobial resistance genes (ARGs). Through the analysis of pairwise ARG abundances in 214K metagenomic samples, we observed that the co-abundance is highly dependent on the environmental context and argue that these correlations can be used to show the risk of co-selection occurring in different settings.


Subject(s)
Anti-Bacterial Agents , Bacteria , Drug Resistance, Bacterial , Metagenomics , Humans , Anti-Bacterial Agents/pharmacology , Bacteria/genetics , Bacteria/drug effects , Bacteria/classification , Drug Resistance, Bacterial/genetics , Animals , Genes, Bacterial/genetics , Soil Microbiology , High-Throughput Nucleotide Sequencing , Metagenome/genetics
9.
Cell Host Microbe ; 32(7): 1147-1162.e12, 2024 Jul 10.
Article in English | MEDLINE | ID: mdl-38917808

ABSTRACT

Gut bacteria are implicated in inflammatory bowel disease (IBD), but the strains driving these associations are unknown. Large-scale studies of microbiome evolution could reveal the imprint of disease on gut bacteria, thus pinpointing the strains and genes that may underlie inflammation. Here, we use stool metagenomes of thousands of IBD patients and healthy controls to reconstruct 140,000 strain genotypes, revealing hundreds of lineages enriched in IBD. We demonstrate that these strains are ancient, taxonomically diverse, and ubiquitous in humans. Moreover, disease-associated strains outcompete their healthy counterparts during inflammation, implying long-term adaptation to disease. Strain genetic differences map onto known axes of inflammation, including oxidative stress, nutrient biosynthesis, and immune evasion. Lastly, the loss of health-associated strains of Eggerthella lenta was predictive of fecal calprotectin, a biomarker of disease severity. Our work identifies reservoirs of strain diversity that may impact inflammatory disease and can be extended to other microbiome-associated diseases.


Subject(s)
Feces , Gastrointestinal Microbiome , Inflammatory Bowel Diseases , Humans , Inflammatory Bowel Diseases/microbiology , Feces/microbiology , Bacteria/classification , Bacteria/genetics , Bacteria/isolation & purification , Metagenome , Phylogeny , Genotype
10.
J Immunol Methods ; 531: 113699, 2024 Aug.
Article in English | MEDLINE | ID: mdl-38823575

ABSTRACT

Bead array assays, such as those sold by Luminex, BD Biosciences, Sartorius, Abcam and other companies, are a well-established platform for multiplexed quantification of cytokines and other biomarkers in both clinical and discovery research environments. In 2011, the National Institute of Allergy and Infectious Diseases (NIAID)-funded External Quality Assurance Program Oversight Laboratory (EQAPOL) established a proficiency assessment program to monitor participating laboratories performing multiplex cytokine measurements using Luminex bead array technology. During every assessment cycle, each site was sent an assay kit, a protocol, and blinded samples of human sera spiked with recombinant cytokines. Site results were then evaluated for performance relative to peer laboratories. After over a decade of biannual assessments, the cumulative dataset contained over 15,500 bead array observations collected at more than forty laboratories in twelve countries. These data were evaluated alongside post-assessment survey results to empirically test factors that may contribute to variability and accuracy in Luminex bead-based cytokine assays. Bead material, individual technical ability, analyte, analyte concentration, and assay kit vendor were identified as significant contributors to assay performance. In contrast, the bead reader instrument model and the use of automated plate washers were found not to contribute to variability or accuracy, and sample results were found to be highly-consistent between assay kit-manufacturing lots and over time. In addition to these statistical analyses, subjective evaluations identified technical ability, instrument failure, protocol adherence, and data transcription errors as the most common causes of poor performance in the proficiency program. The findings from the EQAPOL multiplex program were then used to develop recommended best practices for bead array monitoring of human cytokines. These included collecting samples to assay as a single batch, centralizing analysis, participating in a quality assurance program, and testing samples using paramagnetic-bead kits from a single manufacturer using a standardized protocol.


Subject(s)
Cytokines , Laboratory Proficiency Testing , Humans , Cytokines/blood , Reproducibility of Results , Quality Control , Immunoassay/methods , Immunoassay/standards , United States , Biomarkers/blood
11.
Integr Comp Biol ; 2024 Jun 17.
Article in English | MEDLINE | ID: mdl-38886119

ABSTRACT

Classic debates in community ecology focused on the complexities of considering an ecosystem as a super-organ or organism. New consideration of such perspectives could clarify mechanisms underlying the dynamics of forest carbon dioxide (CO2) uptake and water vapor loss, important for predicting and managing the future of Earth's ecosystems and climate system. Here, we provide a rubric for considering ecosystem traits as aggregated, systemic, or emergent, i.e., representing the ecosystem as an aggregate of its individuals, or as a metaphorical or literal super-organ or organism. We review recent approaches to scaling-up plant water relations (hydraulics) concepts developed for organs and organisms to enable and interpret measurements at ecosystem-level. We focus on three community scale versions of water relations traits that have potential to provide mechanistic insight into climate change responses of CO2 and H2O gas exchange and forest productivity: leaf water potential (Ψcanopy), pressure volume curves (eco-PV), and hydraulic conductance (Keco). These analyses can reveal additional ecosystem-scale parameters analogous to those typically quantified for leaves or plants (e.g., wilting point and hydraulic vulnerability) that may act as thresholds in forest responses to drought including growth cessation, mortality and flammability. We unite these concepts in a novel framework to predict Ψcanopy and its approaching of critical thresholds during drought, using measurements of Keco and eco-PV curves. We thus delineate how extension of water relations concepts from organ- and organism-scales can reveal the hydraulic constraints on the interaction of vegetation and climate, and provide new mechanistic understanding and prediction of forest water use and productivity.

12.
Chem Res Toxicol ; 37(6): 923-934, 2024 Jun 17.
Article in English | MEDLINE | ID: mdl-38842447

ABSTRACT

Benchmark dose (BMD) modeling estimates the dose of a chemical that causes a perturbation from baseline. Transcriptional BMDs have been shown to be relatively consistent with apical end point BMDs, opening the door to using molecular BMDs to derive human health-based guidance values for chemical exposure. Metabolomics measures the responses of small-molecule endogenous metabolites to chemical exposure, complementing transcriptomics by characterizing downstream molecular phenotypes that are more closely associated with apical end points. The aim of this study was to apply BMD modeling to in vivo metabolomics data, to compare metabolic BMDs to both transcriptional and apical end point BMDs. This builds upon our previous application of transcriptomics and BMD modeling to a 5-day rat study of triphenyl phosphate (TPhP), applying metabolomics to the same archived tissues. Specifically, liver from rats exposed to five doses of TPhP was investigated using liquid chromatography-mass spectrometry and 1H nuclear magnetic resonance spectroscopy-based metabolomics. Following the application of BMDExpress2 software, 2903 endogenous metabolic features yielded viable dose-response models, confirming a perturbation to the liver metabolome. Metabolic BMD estimates were similarly sensitive to transcriptional BMDs, and more sensitive than both clinical chemistry and apical end point BMDs. Pathway analysis of the multiomics data sets revealed a major effect of TPhP exposure on cholesterol (and downstream) pathways, consistent with clinical chemistry measurements. Additionally, the transcriptomics data indicated that TPhP activated xenobiotic metabolism pathways, which was confirmed by using the underexploited capability of metabolomics to detect xenobiotic-related compounds. Eleven biotransformation products of TPhP were discovered, and their levels were highly correlated with multiple xenobiotic metabolism genes. This work provides a case study showing how metabolomics and transcriptomics can estimate mechanistically anchored points-of-departure. Furthermore, the study demonstrates how metabolomics can also discover biotransformation products, which could be of value within a regulatory setting, for example, as an enhancement of OECD Test Guideline 417 (toxicokinetics).


Subject(s)
Biotransformation , Liver , Metabolomics , Animals , Rats , Liver/metabolism , Liver/drug effects , Male , Dose-Response Relationship, Drug , Benchmarking , Organophosphates/toxicity , Organophosphates/metabolism , Rats, Sprague-Dawley
14.
Stem Cell Reports ; 19(6): 817-829, 2024 Jun 11.
Article in English | MEDLINE | ID: mdl-38729155

ABSTRACT

Several gaps and barriers remain for transplanting stem cells into the eye to treat ocular disease, especially diseases of the retina. While the eye has historically been considered immune privileged, recent thinking has identified the immune system as both a barrier and an opportunity for eye stem cell transplantation. Recent approaches leveraging scaffolds or cloaking have been considered in other tissues beyond immune suppression. This perspective paper outlines approaches for transplantation and proposes opportunities to overcome barriers of the immune system in stem cell transplantation in the eye.


Subject(s)
Retina , Stem Cell Transplantation , Humans , Retina/immunology , Retina/cytology , Stem Cell Transplantation/methods , Animals , Transplantation Immunology , Retinal Diseases/therapy , Retinal Diseases/immunology
15.
Am J Hypertens ; 37(8): 554-560, 2024 Jul 15.
Article in English | MEDLINE | ID: mdl-38712567

ABSTRACT

BACKGROUND: To compare the pharmacological treatment of hypotension and orthostatic hypotension (OH) initiated based upon a blood pressure (BP) threshold, regardless of symptoms (TXT), to usual care pharmacological treatment of symptomatic hypotension (UC), during acute inpatient rehabilitation (AIR) following spinal cord injury (SCI). METHODS: Block randomization, based on the neurological level of injury as: cervical lesions (C1-C8); high thoracic lesions (T1-T5), and low thoracic lesions (T6-T12), was used to determine responses to the primary question "was the therapy session affected by low BP or concern for low BP development?" Study participants and therapists were unaware of the group assignment. RESULTS: A total of 66 participants enrolled; 25 (38%) in the TXT group, 29 (44%) in the UC group, and 12 (18%) withdrew. Responses to the primary question were recorded for 32 participants, 15 in the TXT, and 17 in the UC group. There was an average of 81 ±â€…51 therapy sessions/participant in the TXT and 60 ±â€…27 sessions/participant in the UC group. Of those therapy sessions, low BP or concerns for low BP affected an average of 9 ±â€…8 sessions/participant in the TXT group and 10 ±â€…12 sessions/participant in the UC group. Neither the total number of therapy sessions (P = 0.16) nor group assignment (P = 0.83) significantly predicted the number of sessions affected by low BP. CONCLUSIONS: These data are not conclusive but indicate that the treatment of asymptomatic hypotension and OH does not increase time spent in therapy compared to UC treatment of symptomatic hypotension and OH in newly injured patients with SCI. CLINICAL TRIALS REGISTRATION: #NCT02919917.


Subject(s)
Blood Pressure , Hypotension, Orthostatic , Spinal Cord Injuries , Humans , Hypotension, Orthostatic/etiology , Hypotension, Orthostatic/physiopathology , Hypotension, Orthostatic/diagnosis , Hypotension, Orthostatic/rehabilitation , Spinal Cord Injuries/complications , Spinal Cord Injuries/rehabilitation , Spinal Cord Injuries/physiopathology , Female , Male , Middle Aged , Adult , Blood Pressure/drug effects , Treatment Outcome , Antihypertensive Agents/therapeutic use , Inpatients , Time Factors , Aged
16.
Lancet Haematol ; 11(6): e425-e435, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38701812

ABSTRACT

BACKGROUND: Realizing Effectiveness Across Continents with Hydroxyurea (REACH) is an open-label non-randomised trial of hydroxyurea (hydroxycarbamide) in children with sickle cell anaemia in sub-Saharan Africa. The short-term results of REACH on safety, feasibility, and effectiveness of hydroxyurea were published previously. In this paper we report results from extended hydroxyurea treatment in the REACH cohort up to 8 years. METHODS: In this open-label, non-randomised, phase 1/2 trial, participants were recruited from four clinical sites in Kilifi, Kenya; Mbale, Uganda; Luanda, Angola; and Kinshasa, Democratic Republic of Congo. Eligible children were 1-10 years old with documented haemoglobin SS or haemoglobin Sß zero thalassaemia, weighing at least 10 kg. Participants received fixed-dose hydroxyurea of 17.5 (±2.5) mg/kg per day for 6 months (fixed-dose phase), followed by 6 months of dose escalation (2·5-5·0 mg/kg increments every 8 weeks) as tolerated, up to 20-35 mg/kg per day (maximum tolerated dose; MTD), defined as mild myelosuppression. After the MTD was reached, hydroxyurea dosing was optimised for each participant on the basis of changes in bodyweight and laboratory values over time (MTD with optimisation phase). After completion of the first 12 months, children with an acceptable toxicity profile and favourable responses were given the opportunity to continue hydroxyurea until the age of 18 years. The safety and feasibility results after 3 years has been reported previously. Here, haematological responses, clinical events, and toxicity rates were compared across the dosing phases (fixed-dose hydroxyurea vs MTD with optimisation phase) as protocol-specified outcomes. REACH is registered on ClinicalTrials.gov (NCT01966731) and is ongoing. FINDINGS: We enrolled 635 children between July 4, 2014, and Nov 11, 2016. 606 children were given hydroxyurea and 522 (86%; 266 [51%] boys and 256 [49%] girls) received treatment for a median of 93 months (IQR 84-97) with 4340 patient-years of treatment. The current (Oct 5, 2023) mean dose is 28·2 (SD 5·2) mg/kg per day with an increased mean haemoglobin concentration (7·3 [SD 1·1] g/dL at baseline to 8·5 [1·5] g/dL) and mean fetal haemoglobin level (10·9% [SD 6·8] to 23·3% [9·5]) and decreased absolute neutrophil count (6·8 [3·0] × 109 cells per L to 3·6 [2·2] × 109 cells per L). Incidence rate ratios (IRR) comparing MTD with fixed-dose hydroxyurea indicate decreased vaso-occlusive episodes (0·60; 95% CI 0·52-0·70; p<0·0001), acute chest syndrome events (0·21; 0·13-0·33; p<0·0001), recurrent stroke events (0·27; 0·07-1·06; p=0·061), malaria infections (0·58; 0·46-0·72; p<0·0001), non-malarial infections (0·52; 0·46-0·58; p<0·0001), serious adverse events (0·42; 0·27-0·67; p<0·0001), and death (0·70; 0·25-1·97; p=0·50). Dose-limiting toxicity rates were similar between the fixed-dose (24·1 per 100 patient-years) and MTD phases (23·2 per 100 patient-years; 0·97; 0·70-1·35; p=0·86). Grade 3 and 4 adverse events were infrequent (18·5 per 100 patient-years) and included malaria infection, non-malarial infections, vaso-occlusive pain, and acute chest syndrome. Serious adverse events were uncommon (3·6 per 100 patient-years) and included malaria infections, parvovirus-associated anaemia, sepsis, and stroke, with no treatment-related deaths. INTERPRETATION: Hydroxyurea dose escalation to MTD with dose optimisation significantly improved clinical responses and treatment outcomes, without increasing toxicities in children with sickle cell anaemia in sub-Saharan Africa. FUNDING: US National Heart, Lung, and Blood Institute and Cincinnati Children's Research Foundation.


Subject(s)
Anemia, Sickle Cell , Antisickling Agents , Hydroxyurea , Humans , Hydroxyurea/therapeutic use , Hydroxyurea/administration & dosage , Hydroxyurea/adverse effects , Anemia, Sickle Cell/drug therapy , Anemia, Sickle Cell/complications , Anemia, Sickle Cell/blood , Child, Preschool , Child , Male , Female , Africa South of the Sahara , Follow-Up Studies , Infant , Antisickling Agents/therapeutic use , Antisickling Agents/adverse effects , Antisickling Agents/administration & dosage , Treatment Outcome , Dose-Response Relationship, Drug
17.
ACS Sens ; 9(5): 2205-2227, 2024 05 24.
Article in English | MEDLINE | ID: mdl-38738834

ABSTRACT

Decarbonization of the energy system is a key aspect of the energy transition. Energy storage in the form of chemical bonds has long been viewed as an optimal scheme for energy conversion. With advances in systems engineering, hydrogen has the potential to become a low cost, low emission, energy carrier. However, hydrogen is difficult to contain, it exhibits a low flammability limit (>40000 ppm or 4%), low ignition energy (0.02 mJ), and it is a short-lived climate forcer. Beyond commercially available sensors to ensure safety through spot checks in enclosed environments, new sensors are necessary to support the development of low emission infrastructure for production, transmission, storage, and end use. Efficient scalable broad area hydrogen monitoring motivates lowering the detection limit below that (10 ppm) of best in class commercial technologies. In this perspective, we evaluate recent advances in hydrogen gas sensing to highlight technologies that may find broad utility in the hydrogen sector. It is clear in the near term that a sensor technology suite is required to meet the variable constraints (e.g., power, size/weight, connectivity, cost) that characterize the breadth of the application space, ranging from industrial complexes to remote pipelines. This perspective is not intended to be another standard hydrogen sensor review, but rather provide a critical evaluation of technologies with detection limits preferably below 1 ppm and low power requirements. Given projections for rapid market growth, promising techniques will also be amenable to rapid development in technical readiness for commercial deployment. As such, methods that do not meet these requirements will not be considered in depth.


Subject(s)
Hydrogen , Hydrogen/chemistry
19.
Am J Bot ; 111(5): e16328, 2024 05.
Article in English | MEDLINE | ID: mdl-38727415

ABSTRACT

PREMISE: Previous studies have suggested a trade-off between trichome density (Dt) and stomatal density (Ds) due to shared cell precursors. We clarified how, when, and why this developmental trade-off may be overcome across species. METHODS: We derived equations to determine the developmental basis for Dt and Ds in trichome and stomatal indices (it and is) and the sizes of epidermal pavement cells (e), trichome bases (t), and stomata (s) and quantified the importance of these determinants of Dt and Ds for 78 California species. We compiled 17 previous studies of Dt-Ds relationships to determine the commonness of Dt-Ds associations. We modeled the consequences of different Dt-Ds associations for plant carbon balance. RESULTS: Our analyses showed that higher Dt was determined by higher it and lower e, and higher Ds by higher is and lower e. Across California species, positive Dt-Ds coordination arose due to it-is coordination and impacts of the variation in e. A Dt-Ds trade-off was found in only 30% of studies. Heuristic modeling showed that species sets would have the highest carbon balance with a positive or negative relationship or decoupling of Dt and Ds, depending on environmental conditions. CONCLUSIONS: Shared precursor cells of trichomes and stomata do not limit higher numbers of both cell types or drive a general Dt-Ds trade-off across species. This developmental flexibility across diverse species enables different Dt-Ds associations according to environmental pressures. Developmental trait analysis can clarify how contrasting trait associations would arise within and across species.


Subject(s)
Plant Stomata , Trichomes , Trichomes/growth & development , Plant Stomata/growth & development , California , Species Specificity , Carbon/metabolism
20.
EClinicalMedicine ; 72: 102640, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38774673

ABSTRACT

Background: Severe pneumonia in African children results in poor long-term outcomes (deaths/readmissions) with undernutrition as a key risk factor. We hypothesised additional energy/protein-rich Ready-to-Use Therapeutic Foods (RUTF) would meet additional nutritional requirements and improve outcomes. Methods: COAST-Nutrition was an open-label Phase 2 randomised controlled trial in children (aged 6 months-12 years) hospitalised with severe pneumonia (and hypoxaemia, SpO2 <92%) in Mbale, Soroti, Jinja, Masaka Regional Referral Hospitals, Uganda and Kilifi County Hospital, Kenya (ISRCTN10829073 (registered 6th June 2018) PACTR202106635355751 (registered 2nd June 2021)). Children were randomised (ratio 1:1) to enhanced nutritional supplementation with RUTF (plus usual diet) for 56 days vs usual diet (control). The primary outcome was change in mid-upper arm circumference (MUAC) at 90 days as a composite with mortality. Secondary outcomes include anthropometric status, mortality, and readmissions at Days 28, 90 and 180. Findings: Between 12 August 2018 and 22 April 2022, 846 eligible children were randomised, 424 to RUTF and 422 to usual diet, and followed for 180-days [12 (1%) lost-to-follow-up]. RUTF supplement was initiated in 417/419 (>99%). By Day 90, there was no significant difference in the composite endpoint (probabilistic index 0.49, 95% CI 0.45-0.53, p = 0.74). Respective 90-day mortality (13/420 3.1% vs 14/421 3.3%) and MUAC increment (0.54 (SD 0.85) vs 0.55 (SD 0.81)) were similar between arms. There was no difference in any anthropometric secondary endpoints to Day 28, 90 or 180 except skinfold thickness at Day 28 and Day 90 was greater in the RUTF arm. Serious adverse events were higher in the RUTF arm (n = 164 vs 108), mainly due to hospital readmission for acute illness (54/387 (14%) vs 37/375 (10%). Interpretation: Our study suggested that nutritional supplementation with RUTF did not improve outcomes to 180 days in children with severe pneumonia. Funding: This trial is part of the EDCTP2 programme (grant number RIA-2016S-1636-COAST-Nutrition) supported by the European Union, and UK Joint Global Health Trials scheme: Medical Research Council, Department for International Development, Wellcome Trust (grant number MR/L004364/1, UK).

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