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1.
Int J Exerc Sci ; 17(2): 576-589, 2024.
Article in English | MEDLINE | ID: mdl-38860033

ABSTRACT

This study investigated the effects of biset, drop-set and traditional resistance training (RT) techniques on metabolic responses in resistance-trained males. Fifteen trained males (age 29.7 ± 6.1 years; body mass 83.4 ± 7.6 kg; RT experience 11.4 ± 6.7 years; one-repetition maximum (1RM) barbell bench press: body mass ratio 1.4 ± 0.1 a.u.) were assigned to three experimental conditions, in a randomized crossover design. The experimental conditions were bi-set (3×10 repetitions at 70%1RM in barbell bench press followed by 10 repetitions at 60%1RM in incline bench press), drop-set (3×10 repetitions at 70%1RM followed by 10 repetitions at 50%1RM in barbell bench press) and traditional RT (3×20 at 60%1RM in barbell bench press). A portable gas analyzer was used to assess energy expenditure and maximal oxygen uptake during the experimental protocols. Blood lactate levels were assessed at baseline and 1, 3, and 5 minutes after the training session. There were no differences for total training volume (p = 0.999). Post hoc comparisons revealed that bi-set elicited higher aerobic energy expenditure (p = 0.003 vs. drop-set; p < 0.001 vs. traditional RT) and aerobic oxygen consumption (p = 0.034 vs. drop-set; p < 0.001 vs. traditional RT) than other RT schemes. There were no differences regarding anaerobic EE between-conditions (p > 0.05). There was a main effect of time and condition for blood lactate levels (p < 0.001). Post hoc comparisons revealed that drop-set training elicited higher blood lactate levels than traditional RT (p = 0.009). The results suggest that RT techniques may have a potential role in optimizing metabolic responses in resistance-trained males.

3.
J Emerg Med ; 67(1): e50-e59, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38821846

ABSTRACT

BACKGROUND: Despite improvements over the past decade, children continue to experience significant pain and distress surrounding invasive procedures in the emergency department (ED). To assess the impact of newly developed interventions, we must create more reliable and valid behavioral assessment tools that have been validated for the unique settings of pediatric EDs. OBJECTIVE: This study aimed to create and test the Emergency Department Child Behavior Coding System (ED-CBCS) for the assessment of child distress and nondistress behaviors surrounding pediatric ED procedures. METHODS: Via an iterative process, a multidisciplinary expert panel developed the ED-CBCS, an advanced time-based behavioral coding measure. Inter-rater reliability and concurrent validity were examined using 38 videos of children aged from 2 to 12 years undergoing laceration procedures. Face, Legs, Activity, Cry, Consolability (FLACC) scale scores were used to examine concurrent validity. RESULTS: The final ED-CBCS included 27 child distress and nondistress behaviors. Time-unit κ values from 0.64 to 0.98 and event alignment κ values from 0.62 to 1.00 indicated good to excellent inter-rater reliability for all but one of the individual codes. ED-CBCS distress (B = 1.26; p < 0.001) and nondistress behaviors (B = -0.69, p = 0.025) were independently significantly associated with FLACC scores, indicating concurrent validity. CONCLUSIONS: We developed a psychometrically sound tool tailored for pediatric ED procedures. Future work could use this measure to better identify behavioral targets and test the effects of interventions to relieve pediatric ED pain and distress.


Subject(s)
Emergency Service, Hospital , Humans , Emergency Service, Hospital/organization & administration , Child , Male , Female , Child, Preschool , Reproducibility of Results , Child Behavior/psychology , Clinical Coding/methods , Clinical Coding/standards , Pediatrics/methods , Pediatrics/standards
4.
Nat Commun ; 15(1): 3715, 2024 May 02.
Article in English | MEDLINE | ID: mdl-38698041

ABSTRACT

Phages play an essential role in controlling bacterial populations. Those infecting Pelagibacterales (SAR11), the dominant bacteria in surface oceans, have been studied in silico and by cultivation attempts. However, little is known about the quantity of phage-infected cells in the environment. Using fluorescence in situ hybridization techniques, we here show pelagiphage-infected SAR11 cells across multiple global ecosystems and present evidence for tight community control of pelagiphages on the SAR11 hosts in a case study. Up to 19% of SAR11 cells were phage-infected during a phytoplankton bloom, coinciding with a ~90% reduction in SAR11 cell abundance within 5 days. Frequently, a fraction of the infected SAR11 cells were devoid of detectable ribosomes, which appear to be a yet undescribed possible stage during pelagiphage infection. We dubbed such cells zombies and propose, among other possible explanations, a mechanism in which ribosomal RNA is used as a resource for the synthesis of new phage genomes. On a global scale, we detected phage-infected SAR11 and zombie cells in the Atlantic, Pacific, and Southern Oceans. Our findings illuminate the important impact of pelagiphages on SAR11 populations and unveil the presence of ribosome-deprived zombie cells as part of the infection cycle.


Subject(s)
Bacteriophages , Ribosomes , Ribosomes/metabolism , Bacteriophages/genetics , Bacteriophages/physiology , Phytoplankton/virology , Phytoplankton/genetics , Phytoplankton/metabolism , In Situ Hybridization, Fluorescence , Alphaproteobacteria/genetics , Alphaproteobacteria/metabolism , Ecosystem , Seawater/microbiology , Seawater/virology , Oceans and Seas
5.
Metab Eng ; 83: 193-205, 2024 May.
Article in English | MEDLINE | ID: mdl-38631458

ABSTRACT

Consolidated bioprocessing (CBP) of lignocellulosic biomass holds promise to realize economic production of second-generation biofuels/chemicals, and Clostridium thermocellum is a leading candidate for CBP due to it being one of the fastest degraders of crystalline cellulose and lignocellulosic biomass. However, CBP by C. thermocellum is approached with co-cultures, because C. thermocellum does not utilize hemicellulose. When compared with a single-species fermentation, the co-culture system introduces unnecessary process complexity that may compromise process robustness. In this study, we engineered C. thermocellum to co-utilize hemicellulose without the need for co-culture. By evolving our previously engineered xylose-utilizing strain in xylose, an evolved clonal isolate (KJC19-9) was obtained and showed improved specific growth rate on xylose by ∼3-fold and displayed comparable growth to a minimally engineered strain grown on the bacteria's naturally preferred substrate, cellobiose. To enable full xylan deconstruction to xylose, we recombinantly expressed three different ß-xylosidase enzymes originating from Thermoanaerobacterium saccharolyticum into KJC19-9 and demonstrated growth on xylan with one of the enzymes. This recombinant strain was capable of co-utilizing cellulose and xylan simultaneously, and we integrated the ß-xylosidase gene into the KJC19-9 genome, creating the KJCBXint strain. The strain, KJC19-9, consumed monomeric xylose but accumulated xylobiose when grown on pretreated corn stover, whereas the final KJCBXint strain showed significantly greater deconstruction of xylan and xylobiose. This is the first reported C. thermocellum strain capable of degrading and assimilating hemicellulose polysaccharide while retaining its cellulolytic capabilities, unlocking significant potential for CBP in advancing the bioeconomy.


Subject(s)
Clostridium thermocellum , Metabolic Engineering , Polysaccharides , Clostridium thermocellum/metabolism , Clostridium thermocellum/genetics , Polysaccharides/metabolism , Polysaccharides/genetics , Xylose/metabolism , Bacterial Proteins/genetics , Bacterial Proteins/metabolism , Cellulose/metabolism , Xylosidases/metabolism , Xylosidases/genetics
7.
Antonie Van Leeuwenhoek ; 117(1): 64, 2024 Apr 02.
Article in English | MEDLINE | ID: mdl-38565745

ABSTRACT

Trichoderma harzianum is a filamentous fungus that can act as a mycoparasite, saprophyte, or a plant symbiotic. It is widely used as a biological control agent against phytopathogenic fungi and can also be used for plant growth promotion and biofortification. Interaction between T. harzianum and phytopathogenic fungi involves mycoparasitism, competition, and antibiosis. Extracellular vesicles (EVs) have been described as presenting a central role in mechanisms of communication and interaction among fungus and their hosts. In this study, we characterized extracellular vesicles of T. harzianum produced during growth in the presence of glucose or S. sclerotiorum mycelia. A set of vesicular proteins was identified using proteomic approach, mainly presenting predicted signal peptides.


Subject(s)
Extracellular Vesicles , Hypocreales , Trichoderma , Trichoderma/metabolism , Proteomics
8.
Philos Trans A Math Phys Eng Sci ; 382(2272): 20230218, 2024 Jun 09.
Article in English | MEDLINE | ID: mdl-38679054

ABSTRACT

The cutoff effect is a significant determinant of solar magnetohydrodynamic wave propagation and hence pivotal in energy transfer studies, such as solar plasma heating and seismological diagnostics. Despite continuous efforts, no good agreement between observed waveperiods and theory or numerical simulations was found. Our objective is to investigate the magnetoacoustic cutoff effect in the partially ionized solar atmosphere, factoring in the two-fluid effects. We developed a two-fluid MHD numerical model and used it to simulate a quiet region of the Sun from the top of the convective zone to the low corona. Our findings show that the ongoing granulation excites a wide range of waves propagating into the upper atmospheric layers. The cutoff waveperiods strongly depend on the height. Two-fluid waveperiods obtained with numerical simulations reproduce the recent observations at a very good level of compliance. Furthermore, direct comparison with strongly coupled cases that imitate the single-fluid approximation have shown that the waveperiod propagation pattern is only present in fully two-fluid simulations. We conclude that the presence of neutrals and therefore collisional terms change the dynamics of the magnetized plasma, in comparison with the single-fluid approximation. This effect is more prominently seen in the upper photosphere and chromosphere. This article is part of the theme issue 'Partially ionized plasma of the solar atmosphere: recent advances and future pathways'.

9.
Arch Cardiol Mex ; 94(1): 48-54, 2024.
Article in English | MEDLINE | ID: mdl-38507313

ABSTRACT

BACKGROUND: Ascending aortic aneurysms are rare pathologies in childhood, especially in the absence of previous diseases such as Marfan syndrome. OBJECTIVE: Present the possibility of successful endovascular management of large vessel aneurysms, using stents and microcatheters with embolization of the aneurysm sac. METHOD: We present the case of a previously healthy ten-year-old patient, in whom a pseudoaneurysm was documented between the origin of the left common carotid artery and left subclavian artery, successfully managed endovascularly, initially with a stent covering the neck of the aneurysm to remodel it and later with embolization of the aneurysm sac using a microcatheter. RESULTS: Aneurysms of large vessels, such common carotid artery and subclavian artery, are at risk of rupture with devastating complications; endovascular management is considered a minimally invasive management option, with favorable results. CONCLUSION: The endovascular management of large vessel aneurysms using stents and microcatheters with embolization of the aneurysmal sac is a novel management option that achieves successful results.


ANTECEDENTES: Los aneurismas de la aorta ascendente son patologías poco frecuentes en la infancia, sobre todo en ausencia de enfermedades previas como el síndrome de Marfan. OBJETIVO: Dar a conocer la posibilidad del manejo endovascular exitoso de los aneurismas de grandes vasos, usando stent y micro catéter con embolización del saco aneurismático. MÉTODO: Presentamos el caso de una paciente de 10 años y 2 meses, previamente sana, en quien se documentó un pseudoaneurisma entre el origen de la arteria carótida común izquierda y la arteria subclavia izquierda, que logró manejarse de forma endovascular, inicialmente con un stent cubriendo el cuello del aneurisma con el fin de remodelarlo y posteriormente por medio de microcatéter se realizó embolización del saco del aneurisma con coils, con resultado exitoso. RESULTADOS: Los aneurismas de los grandes vasos, como la arteria carótida común y la arteria subclavia, tienen riesgo de ruptura con complicaciones devastadoras; el manejo endovascular se plantea como una opción poco invasiva de manejo, con resultados favorables. CONCLUSIÓN: El manejo de aneurismas de grandes vasos, por vía endovascular usando stent y microcatéter con embolización del saco aneurismático, es una opción novedosa de manejo que logra resultados exitosos.


Subject(s)
Aneurysm, Aortic Arch , Aneurysm, False , Aortic Aneurysm, Thoracic , Aortic Aneurysm , Endovascular Procedures , Humans , Child , Aortic Aneurysm/surgery , Stents , Aneurysm, False/diagnostic imaging , Aneurysm, False/surgery , Treatment Outcome , Aortic Aneurysm, Thoracic/surgery
11.
J Neurooncol ; 167(3): 447-454, 2024 May.
Article in English | MEDLINE | ID: mdl-38443693

ABSTRACT

PURPOSE: The use of trametinib in the treatment of pediatric low-grade gliomas (PLGG) and plexiform neurofibroma (PN) is being investigated in an ongoing multicenter phase II trial (NCT03363217). Preliminary data shows potential benefits with significant response in the majority of PLGG and PN and an overall good tolerance. Moreover, possible benefits of MEK inhibitor therapy on cognitive functioning in neurofibromatosis type 1 (NF1) were recently shown which supports the need for further evaluation. METHODS: Thirty-six patients with NF1 (age range 3-19 years) enrolled in the phase II study of trametinib underwent a neurocognitive assessment at inclusion and at completion of the 72-week treatment. Age-appropriate Wechsler Intelligence Scales and the Trail Making Test (for children over 8 years old) were administered at each assessment. Paired t-tests and Reliable Change Index (RCI) analyses were performed to investigate change in neurocognitive outcomes. Regression analyses were used to investigate the contribution of age and baseline score in the prediction of change. RESULTS: Stable performance on neurocognitive tests was revealed at a group-level using paired t-tests. Clinically significant improvements were however found on specific indexes of the Wechsler intelligence scales and Trail Making Test, using RCI analyses. No significant impact of age on cognitive change was evidenced. However, lower initial cognitive performance was associated with increased odds of presenting clinically significant improvements on neurocognitive outcomes. CONCLUSION: These preliminary results show a potential positive effect of trametinib on cognition in patients with NF1. We observed significant improvements in processing speed, visuo-motor and verbal abilities. This study demonstrates the importance of including neuropsychological evaluations into clinical trial when using MEK inhibitors for patients with NF1.


Subject(s)
Neurofibromatosis 1 , Neuropsychological Tests , Pyridones , Pyrimidinones , Humans , Pyridones/therapeutic use , Pyrimidinones/therapeutic use , Pyrimidinones/pharmacology , Pyrimidinones/administration & dosage , Male , Female , Adolescent , Child , Neurofibromatosis 1/drug therapy , Neurofibromatosis 1/complications , Neurofibromatosis 1/psychology , Young Adult , Child, Preschool , Glioma/drug therapy , Glioma/psychology , Glioma/complications , Brain Neoplasms/drug therapy , Brain Neoplasms/psychology , Brain Neoplasms/complications , Adult , Protein Kinase Inhibitors/therapeutic use , Antineoplastic Agents/adverse effects
12.
Am J Orthopsychiatry ; 2024 Mar 28.
Article in English | MEDLINE | ID: mdl-38546563

ABSTRACT

When undocumented immigrant parents are deported from the United States, they must decide whether or not to take their U.S.-born and undocumented immigrant children with them, often to countries the children have never visited or know little about. Other parents do not wait to be deported by the government and decide to relocate to their home countries with or without their children. Both sets of families experience relocation but under different circumstances. These differences deserve exploration to understand the psychological and emotional effects on children's well-being. In this cross-sectional study, we explored differences in self-concept, internalizing and externalizing behaviors, as well as the perception of the home, school, and neighborhood contexts of 178 U.S. citizen children (USCC) whose parents returned to Mexico forcibly and voluntarily. Through snowball sampling, we recruited the sample from two bordering Mexican states, Michoacán and the State of Mexico. Significant estimated marginal mean differences in internalizing and externalizing behavior problems, unhappiness, as well as parent-child conflict and support were found between USCC who relocated due to a parental deportation and those USCC whose parents relocated to Mexico voluntarily. Implications for clinicians in Mexico and the United States include recognizing the reasons, timing, decisions, events, and contexts of relocation. Findings can help inform immigration policies, practices, and future research. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

13.
Sci Rep ; 14(1): 7535, 2024 03 29.
Article in English | MEDLINE | ID: mdl-38553457

ABSTRACT

Cells in obligately multicellular organisms by definition have aligned fitness interests, minimum conflict, and cannot reproduce independently. However, some cells eat other cells within the same body, sometimes called cell cannibalism. Such cell-in-cell events have not been thoroughly discussed in the framework of major transitions to multicellularity. We performed a systematic screening of 508 articles, from which we chose 115 relevant articles in a search for cell-in-cell events across the tree of life, the age of cell-in-cell-related genes, and whether cell-in-cell events are associated with normal multicellular development or cancer. Cell-in-cell events are found across the tree of life, from some unicellular to many multicellular organisms, including non-neoplastic and neoplastic tissue. Additionally, out of the 38 cell-in-cell-related genes found in the literature, 14 genes were over 2.2 billion years old, i.e., older than the common ancestor of some facultatively multicellular taxa. All of this suggests that cell-in-cell events may have originated before the origins of obligate multicellularity. Thus, our results show that cell-in-cell events exist in obligate multicellular organisms, but are not a defining feature of them. The idea of eradicating cell-in-cell events from obligate multicellular organisms as a way of treating cancer, without considering that cell-in-cell events are also part of normal development, should be abandoned.


Subject(s)
Biological Evolution , Neoplasms , Humans , Child, Preschool
14.
Burns ; 50(4): 823-828, 2024 May.
Article in English | MEDLINE | ID: mdl-38492980

ABSTRACT

BACKGROUND: This study aims to establish the significance of social determinants of health and prevalent co-morbidities on multiple indicators for quality of care in patients admitted to the Burn and Surgical Intensive Care Unit (ICU). METHODS: We performed a retrospective analysis of population group data for patients admitted at the Burn and Surgical ICU from January 1, 2016, to November 18, 2019. The primary outcomes were length of hospital stay (LOS), mortality, 30-day readmission, and hospital charges. Pearson's chi-square test for categorical variables and t-test for continuous variables were used to compare population health groups. RESULTS: We analyzed a total of 487 burn and 510 surgical patients. When comparing ICU patients, we observed significantly higher mean hospital charges and length of stay (LOS) in BICU v. SICU patients with a history of mental health ($93,259.40 v. $50,503.36, p = 0.013 and 16.28 v. 9.16 days, p = 0.0085), end-stage-renal-disease (ESRD) ($653,871.05 v. $75,746.35, p = 0.0047 and 96.15 v. 17.53 days, p = 0.0104), sepsis ($267,979.60 v. $99,154.41, p = <0.001 and 39.1 v. 18.42 days, p = 0.0043), and venous thromboembolism (VTE) ($757,740.50 v. $117,816.40, p = <0.001 and 93.11 v. 20.21 days, p = 0.002). Also, higher mortality was observed in burn patients with ESRD, ST-Elevation Myocardial Infarction (STEMI), sepsis, VTE, and diabetes mellitus. 30-day-readmissions were greater among burn patients with a history of mental health, drug dependence, heart failure, and diabetes mellitus. CONCLUSIONS: Our study provides new insights into the variability of outcomes between burn patients treated in different critical care settings, underlining the influence of comorbidities on these outcomes. By comparing burn patients in the BICU with those in the SICU, we aim to highlight how differences in patient backgrounds, including the quality of care received, contribute to these outcomes. This comparison underscores the need for tailored healthcare strategies that consider the unique challenges faced by each patient group, aiming to mitigate disparities in health outcomes and healthcare spending. Further research to develop relevant and timely interventions that can improve these outcomes.


Subject(s)
Burns , Comorbidity , Critical Illness , Length of Stay , Social Determinants of Health , Humans , Burns/epidemiology , Burns/economics , Burns/therapy , Male , Female , Middle Aged , Retrospective Studies , Length of Stay/statistics & numerical data , Social Determinants of Health/statistics & numerical data , Critical Illness/epidemiology , Adult , Aged , Patient Readmission/statistics & numerical data , Hospital Charges/statistics & numerical data , Intensive Care Units/statistics & numerical data , Kidney Failure, Chronic/epidemiology , Mental Disorders/epidemiology , Venous Thromboembolism/epidemiology , Sepsis/epidemiology , Diabetes Mellitus/epidemiology , Heart Failure/epidemiology , Hospital Mortality
15.
bioRxiv ; 2024 Mar 05.
Article in English | MEDLINE | ID: mdl-38496403

ABSTRACT

Brain-machine interfaces (BMI) aim to restore function to persons living with spinal cord injuries by 'decoding' neural signals into behavior. Recently, nonlinear BMI decoders have outperformed previous state-of-the-art linear decoders, but few studies have investigated what specific improvements these nonlinear approaches provide. In this study, we compare how temporally convolved feedforward neural networks (tcFNNs) and linear approaches predict individuated finger movements in open and closed-loop settings. We show that nonlinear decoders generate more naturalistic movements, producing distributions of velocities 85.3% closer to true hand control than linear decoders. Addressing concerns that neural networks may come to inconsistent solutions, we find that regularization techniques improve the consistency of tcFNN convergence by 194.6%, along with improving average performance, and training speed. Finally, we show that tcFNN can leverage training data from multiple task variations to improve generalization. The results of this study show that nonlinear methods produce more naturalistic movements and show potential for generalizing over less constrained tasks. Teaser: A neural network decoder produces consistent naturalistic movements and shows potential for real-world generalization through task variations.

16.
J Pediatr Urol ; 20(3): 522-525, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38360426

ABSTRACT

This educational article highlights the critical role of pediatric urology nursing research in improving the care of children with urological conditions. It discusses the multifaceted nature of pediatric urology nursing, addresses challenges such as limited nurse scientists and resource constraints, and highlights the need to overcome barriers to increase research involvement. The authors emphasize the importance of prioritizing research areas, the promotion of collaboration, and the provision of adequate funding and academic time for pediatric nurses to contribute to evidence-based practice, to improve patient outcomes. Furthermore, it highlights the importance of research in advancing nursing practice, shaping protocols, and advocating for the rights and needs of children with urological conditions and their families.


Subject(s)
Nursing Research , Pediatric Nursing , Quality Improvement , Humans , Child , Urology , Urologic Diseases/therapy , Urologic Diseases/nursing
17.
J Med Virol ; 96(2): e29463, 2024 Feb.
Article in English | MEDLINE | ID: mdl-38345135

ABSTRACT

We present the case of a breakthrough infection by hepatitis B virus (HBV), intending to warn about the challenge that HBV represents for transfusion safety. Virological markers for HBV infection were assayed during a blood donor screening by detection of HBsAg, anti-HBc, and viral nucleic acid (HBV DNA) by a nucleic acid test (NAT). Additionally, samples were analyzed for detection of immunoglobulin M anti-HBc, HBeAg, anti-HBe, and anti-HBs. A first-time donor repeatedly tested positive for HBV DNA by NAT and nonreactive for HBV-serological markers of infection. He stated having completed the anti-HBV vaccination schedule; thus, study of anti-Hbs resulted in reactive at protective level (18 mIU/mL). The donor denied clinical symptoms of hepatitis and remained healthy during the follow-up period. 95 days postdonation, NAT was negative, seroconversion of anti-HBc ab was detected, and a significant increase in anti-HBs concentration was measured (>1000 mIU/mL). This is the first case of HBV-breakthrough infection reported in Argentina and to our knowledge, this potential threat to transfusion safety is novel in an HBV low-endemic region with high coverage of HBV vaccination. The occurrence of breakthrough infections challenges the current protocols for the identification of HBV-infected subjects, could be a source of silent HBV transmission.


Subject(s)
Hepatitis B virus , Hepatitis B , Male , Humans , Hepatitis B virus/genetics , Breakthrough Infections , Blood Donors , DNA, Viral/genetics , Hepatitis B Surface Antigens , Hepatitis B Core Antigens , Hepatitis B/diagnosis , Hepatitis B/prevention & control , Hepatitis B/epidemiology , Hepatitis B Antibodies
18.
Microorganisms ; 12(2)2024 Feb 18.
Article in English | MEDLINE | ID: mdl-38399813

ABSTRACT

Conserved Histidine Alpha-helical Domain (CHAD) proteins attached to the surface of polyphosphate (PolyP) have been studied in some bacteria and one archaeon. However, the activity of CHAD proteins is unknown beyond their interaction with PolyP granules. By using bioinformatic analysis, we report that several species of the biomining acidophilic bacteria contain orthologs of CHAD proteins with high sequence identity. Furthermore, the gene coding for the CHAD protein is in the same genetic context of the enzyme polyphosphate kinase (PPK), which is in charge of PolyP synthesis. Particularly, the group of ppk and CHAD genes is highly conserved. Metallosphaera sedula and other acidophilic archaea used in biomining also contain CHAD proteins. These archaea show high levels of identity in genes coding for a cluster having the same organization. Amongst these genes are chad and ppx. In general, both biomining bacteria and archaea contain high PolyP levels and are highly resistant to heavy metals. Therefore, the presence of this conserved genetic organization suggests a high relevance for their metabolism. It has been formerly reported that a crystallized CHAD protein contains a copper-binding site. Based on this previous knowledge, in the present report, it was determined that all analyzed CHAD proteins are very conserved at their structural level. In addition, it was found that the lack of YgiF, an Escherichia coli CHAD-containing protein, decreases copper resistance in this bacterium. This phenotype was not only complemented by transforming E. coli with YgiF but also by expressing CHAD from Acidithiobacillus ferrooxidans in it. Interestingly, the strains in which the possible copper-binding sites were mutated were also more metal sensitive. Based on these results, we propose that CHAD proteins are involved in copper resistance in microorganisms. These findings are very interesting and may eventually improve biomining operations in the future.

19.
Mol Pharm ; 21(3): 1272-1284, 2024 Mar 04.
Article in English | MEDLINE | ID: mdl-38361428

ABSTRACT

Rifampicin (RIF) is an antibiotic used to treat tuberculosis and leprosy. Even though RIF is a market-available drug, it has a low aqueous solubility, hindering its bioavailability. Among the strategies for bioavailability improvement of poorly soluble drugs, coamorphous systems have been revealed as an alternative in the increase of the aqueous solubility of drug systems and at the same time also increasing the amorphous state stability and dissolution rate when compared with the neat drug. In this work, a new coamorphous form from RIF and tromethamine (TRIS) was synthesized by slow evaporation. Structural, electronic, and thermodynamic properties and solvation effects, as well as drug-coformer intermolecular interactions, were studied through density functional theory (DFT) calculations. Powder X-ray diffraction (PXRD) data allowed us to verify the formation of a new coamorphous. In addition, the DFT study indicates a possible intermolecular interaction by hydrogen bonds between the available amino and carbonyl groups of RIF and the hydroxyl and amino groups of TRIS. The theoretical spectra obtained are in good agreement with the experimental data, suggesting the main interactions occurring in the formation of the coamorphous system. PXRD was used to study the physical stability of the coamorphous system under accelerated ICH conditions (40 °C and 75% RH), indicating that the material remained in an amorphous state up to 180 days. The thermogravimetry result of this material showed a good thermal stability up to 153 °C, and differential scanning calorimetry showed that the glass temperature (Tg) was at 70.0 °C. Solubility studies demonstrated an increase in the solubility of RIF by 5.5-fold when compared with its crystalline counterpart. Therefore, this new material presents critical parameters that can be considered in the development of new coamorphous formulations.


Subject(s)
Rifampin , Tromethamine , Drug Compounding , Solubility , Water , Models, Theoretical , Drug Stability , Calorimetry, Differential Scanning , X-Ray Diffraction
20.
Transl Anim Sci ; 8: txae015, 2024.
Article in English | MEDLINE | ID: mdl-38371423

ABSTRACT

The study investigated the effects of 48-h water and feed deprivation on blood and the performance of grazing Nellore (Bos indicus) heifers. Twenty-four Nellore heifers (initial body weight [BW] = 238 ±â€…10 kg; age = 16 ±â€…2 mo), were ranked by initial BW and age and randomly assigned to one of the two treatments: (1) grazing animals with free access to pasture, water, and mineral-mix (CON; n = 12), or (2) the same grazing conditions but deprived of pasture, water, and mineral-mix for 48 h (DPR; n = 12). The paddocks consisted of Urochloa brizantha cv. Marandu, using a continuous and fixed stocking rate. The experiment lasted 225 d, with the first 14 d considered as the adaptation period (days -14 to -1) and the subsequent 211 d as the evaluation period (days 0 to 211). From days 0 to 2, treatments were applied by keeping the DPR heifers in pens and reintegrating them into the experimental area after a 48-h water and feed deprivation. Individual full BW was recorded on days -14, -13, -1, before (day 0) and after (day 2) treatment application, and on days 6, 11, 12, 41, 42, 210, and 211. Blood samples were collected in the morning on days 0, 2, 6, 12, and 211. A treatment effect was detected (P < 0.001) for shrink BW from days 0 to 2, which was greater (P < 0.001) in DPR vs. CON heifers. Subsequently, DPR animals were lighter (P < 0.001) compared with CON heifers by the end of the deprivation period (day 2). From days 4 to 211, DPR was lighter (P < 0.001) compared with CON heifers after treatment application and for the entire experimental period. In the first 10 d after treatment application (days 2 to 12), DPR heifers showed a partial compensatory average daily gain (ADG; P < 0.001) compared with CON heifers, while no significant differences were observed in ADG between the treatments from days 12 to 42 and 42 to 211 (P > 0.420). Overall ADG (days 2 to 211) was greater (P < 0.001) for DPR vs. CON heifers. All serum variables, except AST, were higher (P < 0.001) in DPR than in CON heifers on day 2 after treatment application. Our study demonstrates that grazing Nellore heifers subjected to 48-h water and feed deprivation experienced significant alterations in their blood metabolites and BW immediately after the stressful event. Although the deprived heifers partially compensated for their BW loss in the early days post-deprivation, they remained 12 kg lighter than the non-deprived animals throughout the production cycle.

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