Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 78
Filtrar
1.
Future Oncol ; 20(1): 17-23, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38189148

RESUMO

Background: Heat shock proteins (HSP) protect cancer cells. Gastrointestinal bacteria contain HSP genes and can release extracellular vesicles which act as biological shuttles. Stress from treatment may result in a microbial community with more HSP genes, which could contribute to circulating HSP levels. Methods: The authors examined the abundance of five bacterial HSP genes pre-treatment and during induction in stool sequences from 30 pediatric acute lymphoblastic leukemia patients. Results: Decreased mean HTPG counts (p = 0.0024) pre-treatment versus induction were observed. During induction, HTPG, Shannon diversity and Bacteroidetes decreased (p = 7.5e-4; 1.1e-3; 8.6e-4), while DNAK and Firmicutes increased (p = 6.9e-3; 9.2e-4). Conclusion: Understanding microbial HSP gene community changes with treatment is the first step in determining if bacterial HSPs are important to the tumor microenvironment and leukemia treatment.


Assuntos
Proteínas de Choque Térmico , Leucemia-Linfoma Linfoblástico de Células Precursoras , Humanos , Criança , Proteínas de Choque Térmico/genética , Proteínas de Choque Térmico/metabolismo , Quimioterapia de Indução , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Proteínas de Choque Térmico HSP70/genética , Proteínas de Choque Térmico HSP70/metabolismo , Proteínas de Choque Térmico HSP90/genética , Proteínas de Choque Térmico HSP90/metabolismo , Microambiente Tumoral
2.
Mult Scler J Exp Transl Clin ; 9(3): 20552173231194352, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37641617

RESUMO

Sleep disturbance is common in people with multiple sclerosis and may worsen fatigue; however, the assessment of sleep-fatigue relationships varies across studies. To better understand sleep-fatigue relationships in this population, we conducted a systematic review and random effects meta-analyses for the associations between fatigue and 10 sleep variables: Sleep-disordered breathing, daytime sleepiness, sleep quality, insomnia, restless legs, number of awakenings, sleep efficiency, sleep latency, sleep duration, and wake after sleep onset. Of the 1062 studies screened, 46 met inclusion criteria and provided sufficient data for calculating Hedges' g. Study quality was assessed using the Newcastle-Ottawa Scale. Sample characteristics did not differ between the 10 analyses. Results indicated that sleep quality and insomnia (assessed via self-report or diagnostic criteria) were strongly associated with fatigue (all gs ≥ 0.80 and all ps < .001). In contrast, the number of awakenings and sleep duration (assessed objectively) were not significantly associated with fatigue. Remaining sleep variables yielded moderate, significant effects. Most effects did not vary based on study quality or sample demographics. Results highlight that insomnia and perceptions of poor sleep have a stronger link than objective sleep duration to fatigue in multiple sclerosis and may represent a more effective target for intervention.

3.
J Clin Psychiatry ; 84(4)2023 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-37195812

RESUMO

Objective: Clinical studies of depression have historically excluded participants with suicidal ideation. Research participant safety protocols are critical to allow for the much-needed study of suicide risk. This report summarizes participant feedback about the safety protocol used in a national, remote study of perinatal women with suicidal ideation.Methods: Upon completion of the study, participants who had triggered the suicidality safety protocol during the study were invited to complete a brief survey with questions about their experiences with the protocol. The survey included 4 Likert-scale questions and 1 open text question where participants could provide feedback, suggestions, and comments to the research team. Participant feedback survey data were collected between October 2021 and April 2022, and this research was funded by the National Institute of Mental Health.Results: Of the 45 participants enrolled in the UPWARD-S study, 16 triggered the safety protocol. All eligible participants (N = 16) completed the survey. Among respondents, most were at least neutral to very comfortable with the call from the study psychiatrist (75% [n = 12]) and reported that the call had a "positive impact" on their well-being (69% [n = 11]). After the call with the study psychiatrist, 50% of participants (n = 8) reported that they increased engagement with treatment for depression, and the other 50% reported no change in treatment. We also report on themes from the qualitative feedback regarding suggestions of how to modify or improve the safety protocol.Conclusions: Learning from the experiences of research participants will provide unique insight into satisfaction with, and impact of, the implemented suicidality safety protocol. Findings from this study could inform the refinement and implementation of safety protocols used in depression studies as well as future research on the impact of such protocols.


Assuntos
Ideação Suicida , Suicídio , Gravidez , Humanos , Feminino , Suicídio/psicologia , Retroalimentação , Previsões
4.
Front Cell Infect Microbiol ; 13: 1102501, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36909730

RESUMO

Introduction: Most children with leukemia and lymphoma experience febrile neutropenia. These are treated with empiric antibiotics that include ß-lactams and/or vancomycin. These are often administered for extended periods, and the effect on the resistome is unknown. Methods: We examined the impact of repeated courses and duration of antibiotic use on the resistome of 39 pediatric leukemia and lymphoma patients. Shotgun metagenome sequences from 127 stool samples of pediatric oncology patients were examined for abundance of antibiotic resistance genes (ARGs) in each sample. Abundances were grouped by repeated courses (no antibiotics, 1-2 courses, 3+ courses) and duration (no use, short duration, long and/or mixed durationg) of ß-lactams, vancomycin and "any antibiotic" use. We assessed changes in both taxonomic composition and prevalence of ARGs among these groups. Results: We found that Bacteroidetes taxa and ß-lactam resistance genes decreased, while opportunistic Firmicutes and Proteobacteria taxa, along with multidrug resistance genes, increased with repeated courses and/or duration of antibiotics. Efflux pump related genes predominated (92%) among the increased multidrug genes. While we found ß-lactam ARGs present in the resistome, the taxa that appear to contain them were kept in check by antibiotic treatment. Multidrug ARGs, mostly efflux pumps or regulators of efflux pump genes, were associated with opportunistic pathogens, and both increased in the resistome with repeated antibiotic use and/or increased duration. Conclusions: Given the strong association between opportunistic pathogens and multidrug-related efflux pumps, we suggest that drug efflux capacity might allow the opportunistic pathogens to persist or increase despite repeated courses and/or duration of antibiotics. While drug efflux is the most direct explanation, other mechanisms that enhance the ability of opportunistic pathogens to handle environmental stress, or other aspects of the treatment environment, could also contribute to their ability to flourish within the gut during treatment. Persistence of opportunistic pathogens in an already dysbiotic and weakened gastrointestinal tract could increase the likelihood of life-threatening blood borne infections. Of the 39 patients, 59% experienced at least one gastrointestinal or blood infection and 60% of bacteremia's were bacteria found in stool samples. Antimicrobial stewardship and appropriate use and duration of antibiotics could help reduce morbidity and mortality in this vulnerable population.


Assuntos
Leucemia , Linfoma , Humanos , Criança , Antibacterianos , Vancomicina , Genes Bacterianos , Trato Gastrointestinal/microbiologia , beta-Lactamas , Leucemia/genética , Linfoma/genética
5.
BMJ Open ; 13(2): e064944, 2023 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-36725090

RESUMO

INTRODUCTION: Early relapse in Crohn's disease (CD) is associated with a more severe disease course. The microbiome plays a crucial role, yet strategies targeting the microbiome are underrepresented in current guidelines. We hypothesise that early manipulation of the microbiome will improve clinical response to standard-of-care (SOC) induction therapy in patients with a relapse-associated microbiome profile. We describe the protocol of a pilot study assessing feasibility of treatment allocation based on baseline faecal microbiome profiles. METHODS AND ANALYSIS: This is a 52-week, multicentre, randomised, controlled, open-label, add-on pilot study to test the feasibility of a larger multicontinent trial evaluating the efficacy of adjuvant antibiotic therapy in 20 paediatric patients with mild-to-moderate-CD (10

Assuntos
Doença de Crohn , Microbiota , Humanos , Criança , Doença de Crohn/tratamento farmacológico , Azitromicina/uso terapêutico , Metronidazol/uso terapêutico , Projetos Piloto , Quimioterapia de Indução/métodos , Metagenoma , Teorema de Bayes , RNA Ribossômico 16S , Antibacterianos/uso terapêutico , Indução de Remissão , Recidiva , Ensaios Clínicos Controlados Aleatórios como Assunto , Estudos Multicêntricos como Assunto
6.
IEEE Rev Biomed Eng ; 16: 499-513, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-35302938

RESUMO

Technologies for quantifying circulating tumour DNA (ctDNA) in liquid biopsies could enable real-time measurements of cancer progression, profoundly impacting patient care. Sequencing methods can be too complex and time-consuming for regular point-of-care monitoring, but nanotechnology offers an alternative, harnessing the unique properties of objects tens to hundreds of nanometres in size. This systematic review was performed to identify all examples of nanotechnology-based ctDNA detection and assess their potential for clinical use. Google Scholar, PubMed, Web of Science, Google Patents, Espacenet and Embase/MEDLINE were searched up to 23rd March 2021. The review identified nanotechnology-based methods for ctDNA detection for which quantitative measures (e.g., limit of detection, LOD) were reported and biologically relevant samples were used. The pre-defined inclusion criteria were met by 66 records. LODs ranged from 10 zM to 50nM. 25 records presented an LOD of 10fM or below. Nanotechnology-based approaches could provide the basis for the next wave of advances in ctDNA diagnostics, enabling analysis at the point-of-care, but none are currently used clinically. Further work is needed in development and validation; trade-offs are expected between different performance measures e.g., number of sequences detected and time to result.


Assuntos
DNA Tumoral Circulante , Neoplasias , Humanos , DNA Tumoral Circulante/genética , Biomarcadores Tumorais/genética , Nanotecnologia , Biópsia Líquida/métodos
8.
J Crohns Colitis ; 17(1): 61-72, 2023 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-36106847

RESUMO

BACKGROUND AND AIMS: Nutritional therapy with the Crohn's Disease Exclusion Diet + Partial Enteral Nutrition [CDED+PEN] or Exclusive Enteral Nutrition [EEN] induces remission and reduces inflammation in mild-to-moderate paediatric Crohn's disease [CD]. We aimed to assess if reaching remission with nutritional therapy is mediated by correcting compositional or functional dysbiosis. METHODS: We assessed metagenome sequences, short chain fatty acids [SCFA] and bile acids [BA] in 54 paediatric CD patients reaching remission after nutritional therapy [with CDED + PEN or EEN] [NCT01728870], compared to 26 paediatric healthy controls. RESULTS: Successful dietary therapy decreased the relative abundance of Proteobacteria and increased Firmicutes towards healthy controls. CD patients possessed a mixture of two metabotypes [M1 and M2], whereas all healthy controls had metabotype M1. M1 was characterised by high Bacteroidetes and Firmicutes, low Proteobacteria, and higher SCFA synthesis pathways, and M2 was associated with high Proteobacteria and genes involved in SCFA degradation. M1 contribution increased during diet: 48%, 63%, up to 74% [Weeks 0, 6, 12, respectively.]. By Week 12, genera from Proteobacteria reached relative abundance levels of healthy controls with the exception of E. coli. Despite an increase in SCFA synthesis pathways, remission was not associated with increased SCFAs. Primary BA decreased with EEN but not with CDED+PEN, and secondary BA did not change during diet. CONCLUSION: Successful dietary therapy induced correction of both compositional and functional dysbiosis. However, 12 weeks of diet was not enough to achieve complete correction of dysbiosis. Our data suggests that composition and metabotype are important and change quickly during the early clinical response to dietary intervention. Correction of dysbiosis may therefore be an important future treatment goal for CD.


Assuntos
Doença de Crohn , Criança , Humanos , Bactérias/genética , Doença de Crohn/tratamento farmacológico , Disbiose/terapia , Escherichia coli , Firmicutes , Proteobactérias , Indução de Remissão , Estudos de Casos e Controles
9.
Bioconjug Chem ; 34(1): 97-104, 2023 01 18.
Artigo em Inglês | MEDLINE | ID: mdl-36121896

RESUMO

Many photonic and electronic devices rely on nanotechnology and nanofabrication, but DNA-based approaches have yet to make a significant commercial impact in these fields even though DNA molecules are now well-established as versatile building blocks for nanostructures. As we describe here, DNA molecules can be chemically modified with a wide variety of functional groups enabling nanocargoes to be attached at precisely determined locations. DNA nanostructures can also be used as templates for the growth of inorganic structures. Together, these factors enable the use of DNA nanotechnology for the construction of many novel devices and systems. In this topical review, we discuss four case studies of potential applications in photonics and electronics: carbon nanotube transistors, devices for quantum computing, artificial electromagnetic materials, and enzymatic fuel cells. We conclude by speculating about the barriers to the exploitation of these technologies in real-world settings.


Assuntos
Nanoestruturas , Óptica e Fotônica , Metodologias Computacionais , Teoria Quântica , Nanotecnologia , Nanoestruturas/química , DNA/química , Eletrônica
10.
JGH Open ; 6(12): 824-832, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36514503

RESUMO

Background and Aim: Colonoscopies are an important diagnostic technique in the detection of colorectal cancer and colonic disease. Adequate examination is dependent on the degree of mucosal visibility, with poor cleansing impeding the detection of neoplasms. These patients require shorter colonoscopy surveillance intervals, longer hospital stays, and increased healthcare costs-rendering a screening colonoscopy cost-ineffective. In Australia and the Gold Coast Hospital and Health Service (GCHHS), macrogol and 3 L of polyethylene glycol are the preferred regimen given its safety profile and efficacy. Yet, little is known locally about the use of the new low-volume bowel preparation NER1006 (Plenvu) given its recent registration with the Therapeutic Goods of Australia (TGA). The primary outcome assessed the bowel cleansing efficacy of NER1006 compared with 7 days of macrogol and 3 L of polyethylene glycol using the Boston Bowel Preparation Scale (BBPS), while also assessing the influence of notable patient characteristics such as age, gender, body mass index (BMI), and the patients Charlson comorbidity index (CCI). Secondary outcomes assessed the polyp detection rate and procedural factors including cecal intubation, scope withdrawal time, and rebooking rates. Methods: Data from all patients who underwent an outpatient colonoscopy procedure at GCHHS between 1 July 2020 and 30 September 2020 were analyzed. Patients were aged 50-74 years of age and were referred for a screening colonoscopy due to a positive fecal occult blood test (FOBT) result from the National Bowel Cancer Screening Program. Results: Of the 238 patients who met the inclusion criteria, 108 patients received NER1006 and 130 patients received macrogol and 3 L polyethylene glycol. NER1006 achieved superior overall (P < 0.001) and right-sided colon cleansing (P = 0.016). There was an even distribution of males and females (P = 0.118), the mean age of both cohorts was <65 years of age. The macrogol and 3 L polyethylene glycol group had a statistically higher BMI (P < 0.001) and CCI (P < 0.001). Cecal intubation success was achieved in both cohorts (≥95%) and scope withdrawal time was ≥6 min, polyp detection was non-superior (P = 0.824), but superior in NER1006 when BBPS ≥6 (P = 0.002). Rebooking rates were significantly lower in the NER1006 group (P = 0.013). Conclusion: This study demonstrated that NER1006 was superior in terms of overall and right-sided bowel cleansing as a primary endpoint. Patient factors demonstrated to be independent predictors of inadequate bowel preparation. Future studies should aim to explore the safety and tolerability of NER1006 while also assessing the bowel cleansing effectiveness in patients with a high BMI and comorbidity index.

11.
Front Cell Infect Microbiol ; 12: 924707, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35967843

RESUMO

Due to decreased immunity, both antibiotics and antifungals are regularly used in pediatric hematologic-cancer patients as a means to prevent severe infections and febrile neutropenia. The general effect of antibiotics on the human gut microbiome is profound, yielding decreased diversity and changes in community structure. However, the specific effect on pediatric oncology patients is not well-studied. The effect of antifungal use is even less understood, having been studied only in mouse models. Because the composition of the gut microbiome is associated with regulation of hematopoiesis, immune function and gastrointestinal integrity, changes within the patient gut can have implications for the clinical management of hematologic malignancies. The pediatric population is particularly challenging because the composition of the microbiome is age dependent, with some of the most pronounced changes occurring in the first three years of life. We investigated how antibiotic and antifungal use shapes the taxonomic composition of the stool microbiome in pediatric patients with leukemia and lymphoma, as inferred from both 16S rRNA and metagenome data. Associations with age, antibiotic use and antifungal use were investigated using multiple analysis methods. In addition, multivariable differential abundance was used to identify and assess specific taxa that were associated with multiple variables. Both antibiotics and antifungals were linked to a general decline in diversity in stool samples, which included a decrease in relative abundance in butyrate producers that play a critical role in host gut physiology (e.g., Faecalibacterium, Anaerostipes, Dorea, Blautia),. Furthermore, antifungal use was associated with a significant increase in relative abundance of opportunistic pathogens. Collectively, these findings have important implications for the treatment of leukemia and lymphoma patients. Butyrate is important for gastrointestinal integrity; it inhibits inflammation, reinforces colonic defense, mucosal immunity. and decreases oxidative stress. The routine use of broad-spectrum anti-infectives in pediatric oncology patients could simultaneously contribute to a decline in gastrointestinal integrity and colonic defense while promoting increases in opportunistic pathogens within the patient gut. Because the gut microbiome has been linked to both short-term clinical outcomes, and longer-lasting health effects, systematic characterization of the gut microbiome in pediatric patients during, and beyond, treatment is warranted.


Assuntos
Leucemia , Linfoma , Animais , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Antifúngicos/farmacologia , Antifúngicos/uso terapêutico , Bactérias , Butiratos , Criança , Pré-Escolar , Humanos , Leucemia/complicações , Leucemia/tratamento farmacológico , Linfoma/tratamento farmacológico , Camundongos , RNA Ribossômico 16S/genética
12.
Biochem Biophys Rep ; 31: 101293, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35677630

RESUMO

Non-canonical forms of DNA are attracting increasing interest for applications in nanotechnology. It is frequently convenient to characterize DNA molecules using a label-free approach such as ultraviolet absorption spectroscopy. In this paper we present the results of our investigation into the use of this technique to probe the folding of quadruplex and triplex nanoswitches. We confirmed that four G-quartets were necessary for folding at sub-mM concentrations of potassium and found that the wrong choice of sequence for the linker between G-tracts could dramatically disrupt folding, presumably due to the presence of kinetic traps in the folding landscape. In the case of the triplex nanoswitch we examined, we found that the UV spectrum showed a small change in absorbance when a triplex was formed. We anticipate that our results will be of interest to researchers seeking to design DNA nanoswitches based on quadruplexes and triplexes.

13.
Gastroenterology ; 163(4): 922-936.e15, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35679949

RESUMO

BACKGROUND & AIMS: The Crohn's disease (CD) exclusion diet (CDED) plus partial enteral nutrition (PEN) and exclusive enteral nutrition (EEN) both induce remission in pediatric CD. CDED+PEN is better tolerated and able to sustain remission. We characterized the changes in fecal metabolites induced by CDED+PEN and EEN and their relationship with remission. METHODS: A total of 216 fecal metabolites were measured in 80 fecal samples at week (W) 0, W6, and W12, of children with mild to moderate CD in a prospective randomized trial comparing CDED+PEN vs EEN. The metabolites were measured using liquid chromatography coupled to mass spectrometry. Metagenome Kyoto Encyclopedia of Genes and Genomes Orthology analysis was performed to investigate the differential functional gene abundance involved in specific metabolic pathways. Data were analyzed according to clinical outcome of remission (W6_rem), no remission (W6_nr), sustained remission (W12_sr), and nonsustained (W12_nsr) remission. RESULTS: A decrease in kynurenine and succinate synthesis and an increase in N-α-acetyl-arginine characterized CDED+PEN W6_rem, whereas changes in lipid metabolism characterized EEN W6_rem, especially reflected by lower levels in ceramides. In contrast, fecal metabolites in EEN W6_nr were comparable to baseline/W0 samples. CDED+PEN W6_rem children maintained metabolome changes through W12. In contrast, W12_nsr children in the EEN group, who resumed a free diet after week 6, did not. The metabolome of CDED+PEN differed from EEN in the purine, pyrimidine, and sphingolipid pathways. A significant differential abundance in several genes involved in these pathways was detected. CONCLUSION: CDED+PEN- and EEN-induced remission are associated with significant changes in inflammatory bowel disease-associated metabolites such as kynurenine, ceramides, amino acids, and others. Sustained remission with CDED+PEN, but not EEN, was associated with persistent changes in metabolites. CLINICALTRIALS: gov, Number NCT01728870.


Assuntos
Doença de Crohn , Arginina , Ceramidas , Criança , Doença de Crohn/diagnóstico , Doença de Crohn/metabolismo , Doença de Crohn/terapia , Dieta , Humanos , Cinurenina/metabolismo , Metaboloma , Estudos Prospectivos , Purinas , Pirimidinas , Indução de Remissão , Esfingolipídeos , Succinatos , Sulfonamidas
15.
IEEE Open J Eng Med Biol ; 2: 26-35, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34812420

RESUMO

The SARS-CoV-2 virus is primarily transmitted through virus-laden fluid particles ejected from the mouth of infected people. Face covers can mitigate the risk of virus transmission but their outward effectiveness is not fully ascertained. Objective: by using a background oriented schlieren technique, we aim to investigate the air flow ejected by a person while quietly and heavily breathing, while coughing, and with different face covers. Results: we found that all face covers without an outlet valve reduce the front flow through by at least 63% and perhaps as high as 86% if the unfiltered cough jet distance was resolved to the anticipated maximum distance of 2-3 m. However, surgical and handmade masks, and face shields, generate significant leakage jets that may present major hazards. Conclusions: the effectiveness of the masks should mostly be considered based on the generation of secondary jets rather than on the ability to mitigate the front throughflow.

16.
Future Oncol ; 17(32): 4371-4387, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34448411

RESUMO

The microbiome consists of all microbes present on and within the human body. An unbalanced, or 'dysbiotic' intestinal microbiome is associated with inflammatory bowel disease, diabetes and some cancer types. Drug treatment can alter the intestinal microbiome composition. Additionally, some chemotherapeutics interact with microbiome components, leading to changes in drug safety and/or efficacy. The intestinal microbiome is a modifiable target, using strategies such as antibiotic treatment, fecal microbial transplantation or probiotic administration. Understanding the impact of the microbiome on the safety and efficacy of cancer treatment may result in improved treatment outcome. The present review seeks to summarize relevant research and look to the future of cancer treatment, where the intestinal microbiome is recognized as an actionable treatment target.


Lay abstract The microbiome describes all of the microorganisms (including bacteria, viruses and fungi) that are normally present on and inside the human body. Some diseases, including cancer, can be caused or worsened by an 'unbalanced' or 'unhealthy' gut microbiome. Some drugs that are given to people who have cancer can change the microbiome. Importantly, components of the gut microbiome can also change how a cancer drug will work in someone. We can change the microbiome in certain ways, like by giving someone antibiotics. Understanding how the microbiome influences the way anticancer drugs work is important because it could help us understand how to make cancer treatment safer and more effective. This review article summarizes available research on the impact of the microbiome on cancer treatment.


Assuntos
Microbioma Gastrointestinal/fisiologia , Neoplasias/etiologia , Antineoplásicos/efeitos adversos , Asparaginase/uso terapêutico , Carcinogênese , Microbioma Gastrointestinal/efeitos dos fármacos , Humanos , Inibidores de Checkpoint Imunológico/farmacologia , Neoplasias/tratamento farmacológico , Neoplasias/microbiologia
17.
Leuk Lymphoma ; 62(13): 3244-3255, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34279176

RESUMO

Treatment of pediatric acute lymphoblastic leukemia (ALL) with pegaspargase exploits ALL cells dependency on asparagine. Pegaspargase depletes asparagine, consequentially affecting aspartate, glutamine and glutamate. The gut as a confounding source of these amino acids (AAs) and the role of gut microbiome metabolism of AAs has not been examined. We examined asparagine, aspartate, glutamine and glutamate in stool samples from patients over pegaspargase treatment. Microbial gene-products, which interact with these AAs were identified. Stool asparagine declined significantly, and 31 microbial genes changed over treatment. Changes were complex, and included genes involved in AA metabolism, nutrient sensing, and pathways increased in cancers. While we identified changes in a gene (iaaA) with limited asparaginase activity, it lacked significance after correction leaving open other mechanisms for asparagine decline, possibly including loss from gut to blood. Understanding pathways that change AA availability, including by microbes in the gut, could be useful in optimizing pegaspargase therapy.


Assuntos
Antineoplásicos , Leucemia-Linfoma Linfoblástico de Células Precursoras , Antineoplásicos/uso terapêutico , Asparaginase/efeitos adversos , Asparagina , Ácido Aspártico , Criança , Genes Bacterianos , Ácido Glutâmico/uso terapêutico , Glutamina/uso terapêutico , Humanos , Polietilenoglicóis/efeitos adversos , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética
18.
Metab Eng Commun ; 13: e00175, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34168957

RESUMO

Phycocyanin (PC) is a soluble phycobiliprotein found within the light-harvesting phycobilisome complex of cyanobacteria and red algae, and is considered a high-value product due to its brilliant blue colour and fluorescent properties. However, commercially available PC has a relatively low temperature stability. Thermophilic species produce more thermostable variants of PC, but are challenging and energetically expensive to cultivate. Here, we show that the PC operon from the thermophilic cyanobacterium Thermosynechococcus elongatus BP-1 (cpcBACD) is functional in the mesophile Synechocystis sp. PCC 6803. Expression of cpcBACD in an 'Olive' mutant strain of Synechocystis lacking endogenous PC resulted in high yields of thermostable PC (112 ± 1 mg g-1 DW) comparable to that of endogenous PC in wild-type cells. Heterologous PC also improved the growth of the Olive mutant, which was further supported by evidence of a functional interaction with the endogenous allophycocyanin core of the phycobilisome complex. The thermostability properties of the heterologous PC were comparable to those of PC from T. elongatus, and could be purified from the Olive mutant using a low-cost heat treatment method. Finally, we developed a scalable model to calculate the energetic benefits of producing PC from T. elongatus in Synechocystis cultures. Our model showed that the higher yields and lower cultivation temperatures of Synechocystis resulted in a 3.5-fold increase in energy efficiency compared to T. elongatus, indicating that producing thermostable PC in non-native hosts is a cost-effective strategy for scaling to commercial production.

19.
Front Med Technol ; 3: 702526, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35047941

RESUMO

During the COVID-19 pandemic, global health services have faced unprecedented demands. Many key workers in health and social care have experienced crippling shortages of personal protective equipment, and clinical engineers in hospitals have been severely stretched due to insufficient supplies of medical devices and equipment. Many engineers who normally work in other sectors have been redeployed to address the crisis, and they have rapidly improvised solutions to some of the challenges that emerged, using a combination of low-tech and cutting-edge methods. Much publicity has been given to efforts to design new ventilator systems and the production of 3D-printed face shields, but many other devices and systems have been developed or explored. This paper presents a description of efforts to reverse engineer or redesign critical parts, specifically a manifold for an anaesthesia station, a leak port, plasticware for COVID-19 testing, and a syringe pump lock box. The insights obtained from these projects were used to develop a product lifecycle management system based on Aras Innovator, which could with further work be deployed to facilitate future rapid response manufacturing of bespoke hardware for healthcare. The lessons learned could inform plans to exploit distributed manufacturing to secure back-up supply chains for future emergency situations. If applied generally, the concept of distributed manufacturing could give rise to "21st century cottage industries" or "nanofactories," where high-tech goods are produced locally in small batches.

20.
Leuk Lymphoma ; 62(4): 927-936, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33258724

RESUMO

Asparaginase (ASNase) is an effective treatment of pediatric acute lymphoblastic leukemia (ALL). Changes in ASNase activity may lead to suboptimal treatment and poorer outcomes. The gut microbiome produces metabolites that could impact ASNase therapy, however, remains uninvestigated. We examined gut-microbial community and microbial-ASNase and asparagine synthetase (ASNS) genes using 16SrRNA and metagenomic sequence data from stool samples of pediatric ALL patients. Comparing ASNase activity between consecutive ASNase-doses, we found microbial communities differed between decreased- and increased-activity samples. Escherichia predominated in the decreased-activity community while Bacteroides and Streptococcus predominated in the increased-activity community. In addition microbial ASNS was significantly (p=.004) negatively correlated with change in serum ASNase activity. These preliminary findings suggest microbial communities prior to treatment could affect serum ASNase levels, although the mechanism is unknown. Replication in an independent cohort is needed, and future research on manipulation of these communities and genes could prove useful in optimizing ASNase therapy.


Assuntos
Antineoplásicos , Microbioma Gastrointestinal , Microbiota , Leucemia-Linfoma Linfoblástico de Células Precursoras , Antineoplásicos/uso terapêutico , Asparaginase/uso terapêutico , Criança , Humanos , Polietilenoglicóis , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...