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1.
New Phytol ; 2024 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-39113419

RESUMO

Crassulacean acid metabolism (CAM) leaves are characterized by nocturnal acidification and diurnal deacidification processes related with the timed actions of phosphoenolpyruvate carboxylase and Rubisco, respectively. How CAM leaves manage cytosolic proton homeostasis, particularly when facing massive diurnal proton effluxes from the vacuole, remains unclear. A 12-phase flux balance analysis (FBA) model was constructed for a mature malic enzyme-type CAM mesophyll cell in order to predict diel kinetics of intracellular proton fluxes. The charge- and proton-balanced FBA model identified the mitochondrial phosphate carrier (PiC, Pi/H+ symport), which provides Pi to the matrix to sustain ATP biosynthesis, as a major consumer of cytosolic protons during daytime (> 50%). The delivery of Pi to the mitochondrion, co-transported with protons, is required for oxidative phosphorylation and allows sufficient ATP to be synthesized to meet the high energy demand during CAM Phase III. Additionally, the model predicts that mitochondrial pyruvate originating from decarboxylation of malate is exclusively exported to the cytosol, probably via a pyruvate channel mechanism, to fuel gluconeogenesis. In this biochemical cycle, glyceraldehyde 3-phosphate dehydrogenase (GAPDH) acts as another important cytosolic proton consumer. Overall, our findings emphasize the importance of mitochondria in CAM and uncover a hitherto unappreciated role in metabolic proton homeostasis.

2.
BMC Ophthalmol ; 24(1): 297, 2024 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-39030539

RESUMO

BACKGROUND: Solitary Punctate Chorioretinitis (SPC) is a recently identified form of punctate inner choroidopathy (PIC) characterized by a single lesion in the fovea of the macula. Previous studies with a maximum follow-up of 48 months were insufficient. Our review uncovered a case sustained for 91 months. CASE PRESENTATION: A 28-year-old young woman experienced with sudden visual loss in her right eye. Comprehensive examinations, including assessment of best-corrected visual acuity (BCVA), slit-lamp biomicroscopy, noncontact tonometry, fundus fluorescein angiography (FFA), fundus autofluorescence (FAF), optical coherence tomography angiography (OCTA), perimetry, and microperimetry, were conducted. Over 91 months, the lesion slightly enlarged, remained yellow-white and punctate, and stayed in the central macula of the posterior pole. OCT images depicted subsidence in the inner nuclear layer (INL), the outer plexiform layer (OPL), photoreceptor layer, and disruption of the external limiting membrane (ELM), ellipsoid zone, and retinal pigment epithelium (RPE)/Bruch's membrane complex. Retinal herniation, focal choroidal excavation (FCE), and abnormal vessels in the choriocapillaris were noted. At the slab of the choriocapillaris, OCTA demonstrated that the lesion resembled a linear vascular structure, distinct from the structure of normal choriocapillaris. This confirmed the lesion as an abnormal vascular formation. FAF revealed a punctate hypo-autofluorescence lesion and abnormal hyper-autofluorescence near the optic disc and macula. FFA demonstrated a punctate hyper-fluorescent lesion inferotemporal to the fovea. The vascular structure remained stable without fluid exudation on OCT images, hence anti-vascular endothelial growth factor (anti-VEGF) treatment was not administered. Visual acuity improved from counting fingers to 0.07 in 52 days, reached 0.6 after 15 months, remained at 0.6 from 56 to 80 months, and returned to 0.8 after 91 months, although accompanied by local scotomas. The lesion pattern slightly enlarged without scarring. CONCLUSIONS: Throughout long-term follow-up, we had long suspected the presence of choroidal neovascularization (CNV) and found the FCE in the last visit. Eventually, we concluded that SPC could potentially constitute a distinct subtype of PIC. The patient received no treatment, and vision recovered to 0.8. If CNV is suspected in SPC, anti-VEGF treatment may not be necessary without activity on OCT, but close monitoring is essential.


Assuntos
Coriorretinite , Angiofluoresceinografia , Tomografia de Coerência Óptica , Acuidade Visual , Humanos , Feminino , Adulto , Coriorretinite/diagnóstico , Seguimentos , Angiofluoresceinografia/métodos , Tomografia de Coerência Óptica/métodos , Acuidade Visual/fisiologia , Fundo de Olho , População do Leste Asiático
3.
Cardiovasc Diabetol ; 23(1): 222, 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38926737

RESUMO

BACKGROUND: Previous studies have shown that an elevated triglyceride-glucose (TyG) index was associated with all-cause mortality in both general adult individuals and critically ill adult patients. However, the relationship between the TyG index and clinical prognosis in pediatric patients admitted to the intensive care unit (ICU) remains unknown. We aimed to investigate the association of the TyG index with in-hospital all-cause mortality in critically ill pediatric patients. METHODS: A total of 5706 patients in the Pediatric Intensive Care database were enrolled in this study. The primary outcome was 30-day in-hospital all-cause mortality, and secondary outcome was 30-day in-ICU all-cause mortality. The restricted cubic spline (RCS) curves and two-piecewise multivariate Cox hazard regression models were performed to explore the relationship between the TyG index and outcomes. RESULTS: The median age of the study population was 20.5 [interquartile range (IQR): 4.8, 63.0] months, and 3269 (57.3%) of the patients were male. The mean TyG index level was 8.6 ± 0.7. A total of 244 (4.3%) patients died within 30 days of hospitalization during a median follow-up of 11 [7, 18] days, and 236 (4.1%) patients died in ICU within 30 days of hospitalization during a median follow-up of 6 [3, 11] days. The RCS curves indicated a U-shape association between the TyG index and 30-day in-hospital and in-ICU all-cause mortality (both P values for non-linear < 0.001). The risk of 30-day in-hospital all-cause mortality was negatively correlated with the TyG index until it bottoms out at 8.6 (adjusted hazard ratio [HR], 0.72, 95% confidence interval [CI] 0.55-0.93). However, when the TyG index was higher than 8.6, the risk of primary outcome increased significantly (adjusted HR, 1.51, 95% CI 1.16-1.96]). For 30-day in-ICU all-cause mortality, we also found a similar relationship (TyG < 8.6: adjusted HR, 0.75, 95% CI 0.57-0.98; TyG ≥ 8.6: adjusted HR, 1.42, 95% CI 1.08-1.85). Those results were consistent in subgroups and various sensitivity analysis. CONCLUSIONS: Our study showed that the association between the TyG index and 30-day in-hospital and in-ICU all-cause mortality was nonlinear U-shaped, with a cutoff point at the TyG index of 8.6 in critically ill pediatric patients. Our findings suggest that the TyG index may be a novel and important factor for the short-term clinical prognosis in pediatric patients.


Assuntos
Biomarcadores , Glicemia , Causas de Morte , Estado Terminal , Bases de Dados Factuais , Mortalidade Hospitalar , Unidades de Terapia Intensiva Pediátrica , Triglicerídeos , Humanos , Masculino , Estado Terminal/mortalidade , Feminino , Estudos Retrospectivos , Glicemia/metabolismo , Triglicerídeos/sangue , Fatores de Risco , Lactente , Pré-Escolar , Fatores de Tempo , Medição de Risco , Biomarcadores/sangue , Prognóstico , Fatores Etários , Criança , Valor Preditivo dos Testes , Mortalidade da Criança
4.
Eur J Appl Physiol ; 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38940932

RESUMO

PURPOSE: To assess the effect of a remote handgrip contraction during wide-pulse high-frequency (WPHF) neuromuscular electrical stimulation (NMES) on the magnitude of extra torque, progressive increase in torque during stimulation, and estimates of the persistent inward current (PIC) contribution to motoneuron firing in the plantar flexors. METHODS: Ten participants performed triangular shaped contractions to 20% of maximal plantar flexion torque before and after WPHF NMES with and without a handgrip contraction, and control conditions. Extra torque, the relative difference between the initial and final torque during stimulation, and sustained electromyographic (EMG) activity were assessed. High-density EMG was recorded during triangular shaped contractions to calculate ∆F, an estimate of PIC contribution to motoneuron firing, and its variation before vs after the intervention referred to as ∆F change score. RESULTS: While extra torque was not significantly increased with remote contraction (WPHF + remote) vs WPHF (+ 37 ± 63%, p = 0.112), sustained EMG activity was higher in this condition than WPHF (+ 3.9 ± 4.3% MVC EMG, p = 0.017). Moreover, ∆F was greater (+ 0.35 ± 0.30 Hz) with WPHF + remote than control (+ 0.03 ± 0.1 Hz, p = 0.028). A positive correlation was found between ∆F change score and extra torque in the WPHF + remote (r = 0.862, p = 0.006). DISCUSSION: The findings suggest that the addition of remote muscle contraction to WPHF NMES enhances the central contribution to torque production, which may be related to an increased PIC contribution to motoneuron firing. Gaining a better understanding of these mechanisms should enable NMES intervention optimization in clinical and rehabilitation settings, improving neuromuscular function in clinical populations.

5.
Clin Exp Med ; 24(1): 107, 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38776019

RESUMO

Predicting the likelihood vascular events in patients with BCR/ABL1-negative myeloproliferative neoplasms (MPN) is essential for the treatment of the disease. However, effective assessment methods are lacking. Thrombin-antithrombin complex (TAT), plasmin-α2- plasmininhibitor complex (PIC), thrombomodulin (TM), and tissue plasminogen activator-inhibitor complex (t-PAIC) are the new direct indicators for coagulation and fibrinolysis. The aim of this study was to investigate the changes of these four new indicators in thrombotic and hemorrhagic events in BCR/ABL1-negative MPN. The study cohort of 74 patients with BCR/ABL negative myeloproliferative disorders included essential thrombocythemia, polycythemia vera, and primary myelofibrosis (PMF). A panel of 4 biomarkers, including TAT, PIC, TM, and t-PAIC were determined using Sysmex HISCL5000 automated analyzers, whereas fibrin/fibrinogen degradation products (FDP), D-dimer and Antithrombin III (ATIII) were analyzed using Sysmex CS5100 coagulation analyzer. A total of 24 (32.4%) patients experienced thrombotic events and hemorrhagic events occurred in 8 patients (10.8%). Compared to patients without hemorrhagic-thrombotic events, patients with thrombotic events had higher fibrinogen (FIB) level, FDP level and lower ATIII activity, while patients with hemorrhagic events had lower white blood cell count and hemoglobin level, higher FDP level (P < 0.05). Patients with a JAK2V617F mutation were more likely to experience thrombotic events (P < 0.05). In addtion, patients with thrombotic events had higher TAT, PIC, TM, and t-PAIC levels than patients without hemorrhagic-thrombotic events (P < 0.05), whereas patients with hemorrhagic events had a lower median value in TAT and TM (no statistical difference, P > 0.05). Patients with higher TAT, TM and t-PAIC were more likely to experience thrombotic events (P < 0.05), and only TAT was positively correlated with thrombotic events (Spearman r =0.287, P = 0.019). TAT, PIC, TM, and t-PAIC combined with ATIII and FDP have a certain value for predicting thrombosis in patients with BCR/ABL1-negative MPN. These 6 parameters are worth further exploration as predictive factors and prognostic markers for early thrombotic events.


Assuntos
Proteínas de Fusão bcr-abl , Transtornos Mieloproliferativos , Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Adulto , Transtornos Mieloproliferativos/sangue , Transtornos Mieloproliferativos/complicações , Transtornos Mieloproliferativos/genética , Transtornos Mieloproliferativos/diagnóstico , Proteínas de Fusão bcr-abl/genética , Trombomodulina/sangue , Fibrinolisina/metabolismo , Fibrinolisina/análise , Idoso de 80 Anos ou mais , Biomarcadores/sangue , Antitrombina III/genética , Trombose , Hemorragia , Relevância Clínica , alfa 2-Antiplasmina , Peptídeo Hidrolases
6.
Int J Biol Macromol ; 268(Pt 2): 131947, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38685542

RESUMO

Trimethoprim (TMP), an antibiotic contaminant, can be effectively removed from water by using the innovative magnetic metal-organic framework (MOF) composite sponge Fe3O4@Rh-MOF@PIC, which is shown in this study. The composite is made up of magnetite (Fe3O4) nanoparticles and a rhodium MOF embedded in a poly(itaconic acid) grafted chitosan matrix. The structure and characteristics of the synthesized material were confirmed by thorough characterization employing SEM, FTIR, XPS, XRD, and BET techniques. Notably, the composite shows a high magnetic saturation of 64 emu g-1, which makes magnetic separation easier, according to vibrating sample magnetometry. Moreover, BET analysis revealed that the Fe3O4@Rh-MOF@PIC sponge had an incredibly high surface area of 1236.48 m2/g. Its outstanding efficacy was confirmed by batch adsorption tests, which produced a maximum adsorption capacity of 391.9 mg/g for the elimination of TMP. Due to its high porosity, magnetic characteristics, and superior trimethoprim uptake, this magnetic MOF composite sponge is a promising adsorbent for effective removal of antibiotics from contaminated water sources. An adsorption energy of 24.5 kJ/mol was found by batch investigations on the Fe3O4@Rh-MOF@PIC composite sponge for trimethoprim (TMP) adsorption. The fact that this value was up 8 kJ/mol suggests that the main mechanism controlling TMP absorption onto the sponge adsorbent is chemisorption. Chemisorption requires creating strong chemical interactions between adsorbate and adsorbent surface groups, unlike weaker physisorption. The magnetic composite sponge exhibited strong removal capabilities and high adsorption capacities for the antibiotic pollutant. The Fe3O4@Rh-MOF@PIC composite sponge also showed magnetism, which allowed for easy magnetic separation after adsorption. Over the course of 6 cycles, it showed outstanding reusability, and XRD confirmed that its composition was stable. The high surface area MOF's pore filling, hydrogen bonding, π-π stacking, and electrostatic interactions were the main trimethoprim adsorption mechanisms. This magnetic composite is feasible and effective for removing antibiotics from water because of its separability, reusability, and synergistic adsorption mechanisms via electrostatics, H-bonding, and π-interactions. The adsorption results were optimized using Box Behnken-design (BBD).


Assuntos
Quitosana , Estruturas Metalorgânicas , Trimetoprima , Águas Residuárias , Poluentes Químicos da Água , Purificação da Água , Quitosana/química , Estruturas Metalorgânicas/química , Trimetoprima/química , Poluentes Químicos da Água/química , Poluentes Químicos da Água/isolamento & purificação , Adsorção , Purificação da Água/métodos , Águas Residuárias/química , Termodinâmica , Cinética , Succinatos
7.
Spectrochim Acta A Mol Biomol Spectrosc ; 313: 124090, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38428163

RESUMO

(-)-Epicatechin gallate (ECG) and piceatannol (PIC) are commonly polyphenols with excellent biological activities. ß-Lactoglobulin (BLG) is a food-grade globule protein and its morphologies are sensitive to pH. This study used experimental and computational methods to determine the interaction of single or combined ECG and PIC with BLG at different pHs. The static quenching process was determined through fluorescence and ultraviolet-visible spectroscopy. Compared with ECG, PIC could significantly bind to BLG with higher affinity. Their binding affinity for BLG with different morphologies followed the tendency of monomer > dimer > tetramer. The negative contribution of van der Waals forces, electrostatic interactions, and hydrogen bonds to ΔHo exceeded the positive contribution of hydrophobic interactions in the spontaneous and exothermic process. The reduced binding affinity in the ternary systems demonstrated the competitive binding between ECG and PIC on BLG, and the hinder effect of ECG or PIC was enhanced with increasing pH. Molecular docking studies revealed the same binding sites of ECG and PIC on various conformations of BLG and identical driven forces as thermodynamic results. Tryptophan and tyrosine were the main participators in the BLG + ECG and BLG + PIC systems, respectively. The conformational changes in the binary and ternary systems could be ascertained through synchronous fluorescence, circular dichroism, and dynamic light scattering. Furthermore, the effects of pH and BLG encapsulation on the antioxidant capacity and stability of ECG or PIC were also implemented. ECG or PIC was the most stable in the (BLG + PIC) + ECG system at pH 6.0. This study could clarify the interaction mechanism between ECG/PIC and BLG and elucidate the pH effect on their binding information. The results will provide basic support for their usage in food processing and applications.


Assuntos
Antioxidantes , Catequina/análogos & derivados , Lactoglobulinas , Estilbenos , Antioxidantes/farmacologia , Simulação de Acoplamento Molecular , Lactoglobulinas/química , Dicroísmo Circular , Ligação Proteica
8.
Int J Mol Sci ; 25(5)2024 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-38473952

RESUMO

The genetic diversity analysis of six dog breeds, including Ca de Bestiar (CB), Ca de Bou (CBOU), Podenco Ibicenco (PI), Ca Rater (CR), Ca Mè (CM), and Ca de Conills (CC), reveals insightful findings. CB showcases the highest mean number of alleles (6.17) and heterozygosity values, with significant deviations from Hardy-Weinberg equilibrium (HWE) observed in five markers, indicating high intra-racial genetic diversity (average observed heterozygosity (Ho) = 0.754, expected heterozygosity (He) = 0.761). In contrast, CBOU presents the lowest mean number of alleles (5.05) and heterozygosity values, coupled with moderate polymorphic information content (PIC) values and a moderate level of intra-racial genetic diversity (average Ho = 0.313, He = 0.394). PI demonstrates moderate genetic diversity with an average of 5.75 alleles and highly informative PIC values, while CR displays robust genetic diversity with an average of 6.61 alleles and deviations from equilibrium, indicating potential risks of inbreeding (average Ho = 0.563, He = 0.658). CM exhibits moderate genetic diversity and deviations from equilibrium, similar to CBOU, with an average of 6.5 alleles and moderate PIC values (average Ho = 0.598, He = 0.676). Conversely, CC shows a wider range of allelic diversity and deviations from equilibrium (average Ho = 0.611, He = 0.706), suggesting a more diverse genetic background. Inter-racial analysis underscores distinct genetic differentiation between breeds, emphasizing the importance of informed breeding decisions and proactive genetic management strategies to preserve diversity, promote breed health, and ensure long-term sustainability across all breeds studied.


Assuntos
Variação Genética , Repetições de Microssatélites , Animais , Cães , Endogamia , Deriva Genética , Marcadores Genéticos , Alelos , Biologia Molecular
9.
Eur J Appl Physiol ; 124(6): 1781-1794, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38340155

RESUMO

PURPOSE: Persistent inward calcium and sodium currents (PICs) are crucial for initiation and maintenance of motoneuron firing, and thus muscular force. However, there is a lack of data describing the effects of fatiguing exercise on PIC activity in humans. We simultaneously applied tendon vibration and neuromuscular electrical stimulation (VibStim) before and after fatiguing exercise. VibStim induces self-sustained muscle activity that is proposed to result from PIC activation. METHODS: Twelve men performed 5-s maximal isometric plantar flexor contractions (MVC) with 5-s rests until joint torque was reduced to 70%MVC. VibStim trials consisted of five 2-s trains of neuromuscular electrical stimulation (20 Hz, evoking 10% MVC) of triceps surae with simultaneous Achilles tendon vibration (115 Hz) without voluntary muscle activation. VibStim was applied before (PRE), immediately (POST), 5-min (POST-5), and 10-min (POST-10) after exercise completion. RESULTS: Sustained torque (Tsust) and soleus electromyogram amplitudes (EMG) measured 3 s after VibStim were reduced (Tsust: -59.0%, p < 0.001; soleus EMG: -38.4%, p < 0.001) but largely recovered by POST-5, and changes in MVC and Tsust were correlated across the four time points (r = 0.69; p < 0.001). After normalisation to values obtained at the end of the vibration phase to control for changes in fibre-specific force and EMG signal characteristics, decreases in Tsust (-42.9%) and soleus EMG (-22.6%) remained significant and were each correlated with loss and recovery of MVC (r = 0.41 and 0.46, respectively). CONCLUSION: The parallel changes observed in evoked self-sustained muscle activity and force generation capacity provide motivation for future examinations on the potential influence of fatigue-induced PIC changes on motoneuron output.


Assuntos
Fadiga Muscular , Músculo Esquelético , Humanos , Masculino , Fadiga Muscular/fisiologia , Músculo Esquelético/fisiologia , Adulto , Contração Isométrica/fisiologia , Torque , Estimulação Elétrica/métodos , Vibração , Eletromiografia , Contração Muscular/fisiologia , Tendão do Calcâneo/fisiologia , Adulto Jovem
10.
Trends Biochem Sci ; 49(2): 145-155, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-38218671

RESUMO

Eukaryotic transcription starts with the assembly of a preinitiation complex (PIC) on core promoters. Flanking this region is the +1 nucleosome, the first nucleosome downstream of the core promoter. While this nucleosome is rich in epigenetic marks and plays a key role in transcription regulation, how the +1 nucleosome interacts with the transcription machinery has been a long-standing question. Here, we summarize recent structural and functional studies of the +1 nucleosome in complex with the PIC. We specifically focus on how differently organized promoter-nucleosome templates affect the assembly of the PIC and PIC-Mediator on chromatin and result in distinct transcription initiation.


Assuntos
Cromatina , Nucleossomos , Nucleossomos/genética , Cromatina/genética , Regiões Promotoras Genéticas , Transcrição Gênica , RNA Polimerase II/metabolismo
11.
mBio ; 15(1): e0273723, 2024 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-38095872

RESUMO

IMPORTANCE: Eukaryotic hosts have defense mechanisms that may disrupt molecular transactions along the pathogen's chromosome through excessive DNA damage. Given that DNA damage stalls RNA polymerase (RNAP) thereby increasing mutagenesis, investigating how host defense mechanisms impact the movement of the transcription machinery on the pathogen chromosome is crucial. Using a new methodology we developed, we elucidated the dynamics of RNAP movement and association with the chromosome in the pathogenic bacterium Salmonella enterica during infection. We found that dynamics of RNAP movement on the chromosome change significantly during infection genome-wide, including at regions that encode for key virulence genes. In particular, we found that there is pervasive RNAP backtracking on the bacterial chromosome during infections and that anti-backtracking factors are critical for pathogenesis. Altogether, our results suggest that, interestingly, the host environment can promote the development of antimicrobial resistance and hypervirulence as stalled RNAPs can accelerate evolution through increased mutagenesis.


Assuntos
RNA Polimerases Dirigidas por DNA , Transcrição Gênica , RNA Polimerases Dirigidas por DNA/genética , RNA Polimerases Dirigidas por DNA/metabolismo , Escherichia coli/genética , Bactérias/genética , Bactérias/metabolismo , Virulência
12.
Gene ; 893: 147959, 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-37923091

RESUMO

RSC (remodels the structure of chromatin) is an essential ATP-dependent chromatin remodeling complex in Saccharomyces cerevisiae. RSC utilizes its ATPase subunit, Sth1, to slide or remove nucleosomes. RSC has been shown to regulate the width of the nucleosome-depleted regions (NDRs) by sliding the flanking nucleosomes away from NDRs. As such, when RSC is depleted, nucleosomes encroach NDRs, leading to transcription initiation defects. In this study, we examined the effects of the catalytic-dead Sth1 on transcription and compared them to those observed during acute and rapid Sth1 depletion by auxin-induced degron strategy. We found that rapid depletion of Sth1 reduces recruitment of TBP and Pol II in highly transcribed genes, as would be expected considering its role in regulating chromatin structure at promoters. In contrast, cells harboring the catalytic-dead Sth1 (sth1-K501R) exhibited a severe reduction in TBP binding, but, surprisingly, also displayed a substantial accumulation in Pol II occupancies within coding regions. The Pol II occupancies further increased upon depleting endogenous Sth1 in the catalytic-dead mutant, suggesting that the inactive Sth1 contributes to Pol II accumulation in coding regions. Notwithstanding the Pol II increase, the ORF occupancies of histone chaperones, FACT and Spt6 were significantly reduced in the mutant. These results suggest a potential role for RSC in recruiting/retaining these chaperones in coding regions. Pol II accumulation despite substantial reductions in TBP, FACT, and Spt6 occupancies in the catalytic-dead mutant could indicate severe transcription elongation and termination defects. Such defects would be consistent with studies showing that RSC is recruited to coding regions in a transcription-dependent manner. Thus, these findings imply a role for RSC in transcription elongation and termination processes, in addition to its established role in transcription initiation.


Assuntos
Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae , Cromatina/genética , Cromatina/metabolismo , Proteínas de Ligação a DNA/genética , Proteínas de Grupo de Alta Mobilidade/genética , Nucleossomos/genética , Nucleossomos/metabolismo , RNA Polimerase II/genética , RNA Polimerase II/metabolismo , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Fatores de Transcrição/metabolismo , Transcrição Gênica , Fatores de Elongação da Transcrição/genética
13.
Global Health ; 19(1): 90, 2023 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-37996877

RESUMO

INTRODUCTION: Pooled procurement can be seen as a collaboration initiative of buyers. Such mechanisms have received increased attention during the Covid-19 pandemic to improve access to affordable and quality-assured health commodities. The structural form of pooled procurement mechanisms ranges from a third-party organization that procures on behalf of its buyers to a buyer's owned mechanism in which buyers operate more collaboratively. However, little is known about how these types of pooled procurement mechanisms differ in terms of characteristics, implementation and developmental process. To fill this gap, we compared four pooled procurement mechanisms. Two buyer's owned mechanisms: the Organisation of the Eastern Caribbean States (OECS) and the Pacific Island Countries (PIC). And two third-party mechanisms: the Global Drug Facility (GDF) and the Asthma Drug Facility (ADF). METHODS: For this qualitative study, we used a multiple case-study design. The cases were purposefully selected, based on a most-similar case study design. We used the Pooled Procurement Guidance to collect data on individual cases and compared our findings between the case studies. For our analysis, we drew upon peer-reviewed academic articles, grey literature documents and 9 semi-structured interviews with procurement experts. RESULTS: Buyers within a buyer's owned mechanisms differ in procurement systems, financing structures, product needs and regulatory and legal frameworks. Therefore, buyers within such mechanisms require relative alignment on motivations, goals and operations of the mechanism. Our study showed that buyers' relative homogeneity of characteristics and their perceived urgency of the problems was particularly relevant for achieving that alignment. Third-party organization mechanisms require less alignment and consensus-building between buyers. To participate, buyers need to align with the operations of the third-party organization, instead of other buyers. Elements that were essential for the successful implementation and operation of such mechanisms included the procurement secretariat's ability to create local and global awareness around the problem, to induce political will to act upon the problem, to mobilize sufficient funding and to attract qualified staff. CONCLUSION: To successfully sustain pooled procurement mechanisms over time, key actors should drive the mechanism through continuous and reflexive work on stakeholder engagement, mobilization of funding and alignment of interests and needs.


Assuntos
Organizações , Pandemias , Humanos , Região do Caribe , Ilhas do Pacífico
14.
Biol Futur ; 74(4): 489-506, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37889451

RESUMO

Antiviral peptides (AVPs) open new possibilities as an effective antiviral therapeutic in the current scenario of evolving drug-resistant viruses. Knowledge about the sequence and structure activity relationship in AVPs is still largely unknown. AVPs and antimicrobial peptides (AMPs) share several common features but as they target different life forms (living organisms and viruses), exploring the differential sequence features may facilitate in designing specific AVPs. The current work developed accurate prediction models for discriminating (a) AVPs from AMPs, (b) Coronaviridae AVPs from other virus family specific AVPs and (c) highly active AVPs (HAA) from lowly active AVPs (LAA). Further explainable machine learning methods (using model agnostic global interpretable methods) are utilized for exploring and interpreting the physicochemical spaces of AVPs, Coronaviridae AVPs and highly active AVPs. To further understand the association of physicochemical space distribution with pIC50 values, regression models were developed and analyzed using accumulated local effects and interaction strength analysis. An independent sample t-test is used to filter out the significant compositional differences between the smaller length HAA and longer length HAA groups. AVPs prefer lower charge/length ratio and basic residues in comparison with AMPs. Coronaviridae family-specific AVPs have lower propensities for basic amino acids, charge and preference for aspartic acid. Further there is prevalence for basic residues in lowly active AVPs as compared to highly active AVPs. Sequence order effects captured in terms of average amino acid pair distances proved to be more constructive in deciphering the sequences of AVPs.


Assuntos
Antivirais , Peptídeos , Sequência de Aminoácidos , Antivirais/farmacologia , Antivirais/química
15.
Sensors (Basel) ; 23(18)2023 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-37765822

RESUMO

The use of composite materials has seen widespread adoption in modern aerospace industry. This has been facilitated due to their favourable mechanical characteristics, namely, low weight and high stiffness and strength. For broader implementation of those materials though, the out-of-autoclave production processes have to be optimized, to allow for higher reliability of the parts produced as well as cost reduction and improved production speed. This optimization can be achieved by monitoring and controlling resin filling and curing cycles. Photonic Integrated Circuits (PICs), and, in particular, Silicon Photonics, owing to their fast response, small size, ability to operate at higher temperatures, immunity to electromagnetic interference, and compatibility with CMOS fabrication techniques, can offer sensing solutions fulfilling the requirements for composite material production using carbon fibres. In this paper, we demonstrate a passive optical temperature sensor, based on a 220 nm height Silicon-on-Insulator platform, embedded in a composite tool used for producing RTM-6 composite parts of high quality (for use in the aerospace industry). The design methodology of the photonic circuit as well as the experimental results and comparison with the industry standard thermocouples during a thermal cycling of the tool are presented. The optical sensor exhibits high sensitivity (85 pm/°C), high linearity (R2 = 0.944), and is compatible with the RTM-6 production process, operating up to 180 °C.

16.
Thromb J ; 21(1): 91, 2023 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-37674235

RESUMO

BACKGROUND: Upon cellular injury, damage-associated molecular patterns (DAMPs) are released into the extracellular space and evoke proinflammatory and prothrombotic responses in animal models of sterile inflammation. However, in clinical settings, the dynamics of DAMP levels after trauma and links between DAMPs and trauma-associated coagulopathy remain largely undetermined. METHODS: Thirty-one patients with severe trauma, who were transferred to Kagoshima City Hospital between June 2018 and December 2019, were consecutively enrolled in this study. Blood samples were taken at the time of delivery, and 6 and 12 h after the injury, and once daily thereafter. The time-dependent changes of coagulation/fibrinolysis markers, including thrombin-antithrombin complex, α2-plasmin inhibitor (α2-PI), plasmin-α2-PI complex, and plasminogen activator inhibitor-1 (PAI-1), and DAMPs, including high mobility group box 1 and histone H3, were analyzed. The relationship between coagulation/fibrinolysis markers, DAMPs, Injury Severity Score, in-hospital death, and amount of blood transfusion were analyzed. RESULTS: The activation of coagulation/fibrinolysis pathways was evident at the time of delivery. In contrast, PAI-1 levels remained low at the time of delivery, and then were elevated at 6-12 h after traumatic injury. Histone H3 and high mobility group box 1 levels were elevated at admission, and gradually subsided over time. PAI-1 levels at 6 h were associated with serum histone H3 levels at admission. Increased histone H3 levels and plasmin-α2-PI complex levels were associated with in-hospital mortality. α2-PI levels at admission showed the strongest negative correlation with the amount of blood transfusion. CONCLUSION: The elevation of histone H3 levels and fibrinolysis perturbation are associated with fatal outcomes in patients with traumatic injury. Patients with low α2-PI levels at admission tend to require blood transfusion.

17.
Ann Anat ; 250: 152158, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37666464

RESUMO

BACKGROUND: Polyinosinic-polycytidylic acid (pIC) is a synthetic analog of double-stranded RNA. It is used as a synthetic adjuvant to induce an adaptive immune response. However, the effect of pIC on the development of mediastinal fat-associated lymphoid clusters (MFALCs) that regulate intrathoracic hemostasis has remained unidentified. METHODS: We investigated the impact of intranasal (i.n.) administration (pIC i.n. group) and intravenous (i.v.) administration (pIC i.v. group) of pIC on both MFALCs and lung tissue. RESULTS: Compared with the control phosphate-buffered saline (PBS) groups, both pIC-administered groups displayed a significant increase in the MFALC size (particularly in the pIC i.n. group), area of MFALC high endothelial venules (HEVs), area of lymphatic vessels (LVs), number of proliferating cells (particularly in the pIC i.v. group), and number of immune cells (B220+ B-lymphocytes, CD3+ T-lymphocytes, Iba1+ macrophages, and Gr-1+ granulocytes) in both MFALCs and lung tissues. In addition, a positive correlation was detected between MFALC size and proliferating cells, immune cell population, LVs, and HEVs within MFALCs in both groups. Except for the proliferating cell and B-lymphocyte populations in the i.n. administered group and granulocyte populations in both i.n. and i.v. administered routes, such correlations were significant. CONCLUSION: In all, our data indicate that local or systemic administration of pIC induces the development of MFALCs and can be used as an immunostimulant therapeutic strategy.


Assuntos
Vasos Linfáticos , Poli I-C , Camundongos , Animais , Poli I-C/farmacologia , Poli I-C/uso terapêutico , Pulmão , Linfócitos T , Linfócitos B
18.
Mol Biol Rep ; 50(10): 8603-8613, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37653359

RESUMO

BACKGROUND: Tef is an indigenous and important food, feed, and cash crop for smallholder Ethiopian farmers. Knowledge of the natural genetic composition of the crop provides the option to further exploit its genetic potential through breeding. However, there are insufficient reports on the genetic variability of Ethiopian tef using a medium-throughput marker system. Hence, the current study was designed to evaluate the genetic variability of released and core germplasm that was collected earlier. METHODS AND RESULTS: Eighty-one tef genotypes collected from eight Ethiopian ecological zones and released varieties were targeted using 14 SSR markers. The study yielded a total of 122 alleles across the entire locus and population. The molecular variance analysis indicated the existence of large genetic differentiation (FIS and FIT = 0.87), with 86% and 13% of the total variation accounted for among genotypes within the population and across all genotypes used for this study, respectively. However, low genetic differentiation among the populations (FST = 0.014, which accounts for 1%) was observed. Multivariate analyses such as clustering and PCoA did not cluster genotypes into distinct groups according to their geographical areas of population. This is presumably due to gene flow among populations. CONCLUSION: In conclusion, our findings show that there is significant genetic diversity within populations, particularly in the Jimma, Tigray, and released varieties, as well as the presence of private alleles and heterozygosity. The study also indicates the existence of genotypic admixture in the studied materials. The identification of private alleles and their differentiation will be helpful in selecting breeding materials and creating breeding plans.


Assuntos
Variação Genética , Repetições de Microssatélites , Repetições de Microssatélites/genética , Genótipo , Heterozigoto , Alelos , Variação Genética/genética
19.
BMC Musculoskelet Disord ; 24(1): 542, 2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-37393235

RESUMO

BACKGROUND: Spontaneous intramuscular hemorrhage (SIH) is a rare but life-threatening complication of dermatomyositis (DM). The pathogenetic mechanism and management of intramuscular hematoma in these patients remains unclear. Here we discuss a case of recurrent hemorrhage in a patient with cancer-associated DM, and review the relevant literature for timely diagnosis and treatment. CASE PRESENTATION: A 53-year-old male patient presented with rashes, muscle weakness, and dysphagia and was diagnosed with DM. During treatment, he developed SIH of the arm and right psoas major muscle successively. MRI showed extensive edema of the right shoulder girdle muscle and muscle groups of the upper arm. During the second SIH, a CT scan showed new-onset hematoma formation in the right psoas major muscle. The detection of D-dimer, thrombin-antithrombin III complex (TAT), plasmin-α2-plasmininhibitor complex (PIC) and tissue plasminogen activator-inhibitor complex (t-PAIC) indicated predominant hyperfibrinolysis over thrombosis. Blood transfusion and supportive treatment were immediately performed, and the hematoma did not expand. However, his abdominal distension was not relieved after active treatment. Further electronic gastroscopy discovered gastric sinus ulcers, and histopathology of the biopsy confirmed signet-ring cell carcinoma. CONCLUSIONS: Although patients with cancer-associated DM have an increased risk of thrombosis, prophylactic anticoagulation therapy needs deliberate consideration. It is important to monitor the coagulation parameters dynamically during anticoagulation therapy. Especially when the level of D-dimer is high, and it is uncertain whether the patient is in a state of thrombosis or hyperfibrinolysis, the detection of TAT, PIC, t-PAIC can help to determine whether to initiate anticoagulation therapy.


Assuntos
Dermatomiosite , Neoplasias , Masculino , Humanos , Pessoa de Meia-Idade , Ativador de Plasminogênio Tecidual , Dermatomiosite/complicações , Hemorragia , Hematoma/diagnóstico por imagem , Hematoma/etiologia , Neoplasias/complicações , Neoplasias/diagnóstico por imagem , Anticoagulantes
20.
Front Physiol ; 14: 1182719, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37469560

RESUMO

Background: Ventricular septal defect is a common congenital heart disease. As the disease progresses, the likelihood of lung infection and heart failure increases, leading to prolonged hospital stays and an increased likelihood of complications such as nosocomial infections. We aimed to develop a nomogram for predicting hospital stays over 14 days in pediatric patients with ventricular septal defect and to evaluate the predictive power of the nomogram. We hope that nomogram can provide clinicians with more information to identify high-risk groups as soon as possible and give early treatment to reduce hospital stay and complications. Methods: The population of this study was pediatric patients with ventricular septal defect, and data were obtained from the Pediatric Intensive Care Database. The resulting event was a hospital stay longer than 14 days. Variables with a variance inflation factor (VIF) greater than 5 were excluded. Variables were selected using the least absolute shrinkage and selection operator (Lasso), and the selected variables were incorporated into logistic regression to construct a nomogram. The performance of the nomogram was assessed by using the area under the receiver operating characteristic curve (AUC), Decision Curve Analysis (DCA) and calibration curve. Finally, the importance of variables in the model is calculated based on the XGboost method. Results: A total of 705 patients with ventricular septal defect were included in the study. After screening with VIF and Lasso, the variables finally included in the statistical analysis include: Brain Natriuretic Peptide, bicarbonate, fibrinogen, urea, alanine aminotransferase, blood oxygen saturation, systolic blood pressure, respiratory rate, heart rate. The AUC values of nomogram in the training cohort and validation cohort were 0.812 and 0.736, respectively. The results of the calibration curve and DCA also indicated that the nomogram had good performance and good clinical application value. Conclusion: The nomogram established by BNP, bicarbonate, fibrinogen, urea, alanine aminotransferase, blood oxygen saturation, systolic blood pressure, respiratory rate, heart rate has good predictive performance and clinical applicability. The nomogram can effectively identify specific populations at risk for adverse outcomes.

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