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1.
Int J Mol Sci ; 25(15)2024 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-39126069

RESUMO

Gastrochilus is an orchid genus containing about 70 species in tropical and subtropical Asia with high morphological diversity. The phylogenetic relationships among this genus have not been fully resolved, and the plastome evolution has not been investigated either. In this study, five plastomes of Gastrochilus were newly reported, and sixteen plastomes of Gastrochilus were used to conduct comparative and phylogenetic analyses. Our results showed that the Gastrochilus plastomes ranged from 146,183 to 148,666 bp, with a GC content of 36.7-36.9%. There were 120 genes annotated, consisting of 74 protein-coding genes, 38 tRNA genes, and 8 rRNA genes. No contraction and expansion of IR borders, gene rearrangements, or inversions were detected. Additionally, the repeat sequences and codon usage bias of Gastrochilus plastomes were highly conserved. Twenty hypervariable regions were selected as potential DNA barcodes. The phylogenetic relationships within Gastrochilus were well resolved based on the whole plastome, especially among main clades. Furthermore, both molecular and morphological data strongly supported Haraella retrocalla as a member of Gastrochilus (G. retrocallus).


Assuntos
Código de Barras de DNA Taxonômico , Evolução Molecular , Orchidaceae , Filogenia , Orchidaceae/genética , Orchidaceae/classificação , Código de Barras de DNA Taxonômico/métodos , Genomas de Plastídeos
2.
Ecotoxicol Environ Saf ; 280: 116540, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38833982

RESUMO

The widespread utilization of polyethylene terephthalate (PET) has caused a variety of environmental and health problems. Compared with traditional thermomechanical or chemical PET cycling, the biodegradation of PET may offer a more feasible solution. Though the PETase from Ideonalla sakaiensis (IsPETase) displays interesting PET degrading performance under mild conditions; the relatively low thermal stability of IsPETase limits its practical application. In this study, enzyme-catalysed PET degradation was investigated with the promising IsPETase mutant HotPETase (HP). On this basis, a carbohydrate-binding module from Bacillus anthracis (BaCBM) was fused to the C-terminus of HP to construct the PETase mutant (HLCB) for increased PET degradation. Furthermore, to effectively improve PET accessibility and PET-degrading activity, the truncated outer membrane hybrid protein (FadL) was used to expose PETase and BaCBM on the surface of E. coli (BL21with) to develop regenerable whole-cell biocatalysts (D-HLCB). Results showed that, among the tested small-molecular weight ester compounds (p-nitrophenyl phosphate (pNPP), p-Nitrophenyl acetate (pNPA), 4-Nitrophenyl butyrate (pNPB)), PETase displayed the highest hydrolysing activity against pNPP. HP displayed the highest catalytic activity (1.94 µM(p-NP)/min) at 50 °C and increased longevity at 40 °C. The fused BaCBM could clearly improve the catalytic performance of PETase by increasing the optimal reaction temperature and improving the thermostability. When HLCB was used for PET degradation, the yield of monomeric products (255.7 µM) was ∼25.5 % greater than that obtained after 50 h of HP-catalysed PET degradation. Moreover, the highest yield of monomeric products from the D-HLCB-mediated system reached 1.03 mM. The whole-cell catalyst D-HLCB displayed good reusability and stability and could maintain more than 54.6 % of its initial activity for nine cycles. Finally, molecular docking simulations were utilized to investigate the binding mechanism and the reaction mechanism of HLCB, which may provide theoretical evidence to further increase the PET-degrading activities of PETases through rational design. The proposed strategy and developed variants show potential for achieving complete biodegradation of PET under mild conditions.


Assuntos
Biodegradação Ambiental , Burkholderiales , Escherichia coli , Polietilenotereftalatos , Polietilenotereftalatos/química , Polietilenotereftalatos/metabolismo , Burkholderiales/enzimologia , Escherichia coli/genética , Bacillus anthracis/enzimologia , Proteínas de Bactérias/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/química , Engenharia de Proteínas
3.
Work ; 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38848148

RESUMO

BACKGROUND: Obstructive Sleep Apnea (OSA) is a temporary airflow obstruction during periods of sleep. Patients with OSA often suffer from poor work performance, compromised sleep quality, and low quality of life which may lead to a life-threatening event. Adequate knowledge and a positive attitude toward OSA among medical and dental practitioners are crucial to the initial diagnosis and treatment. OBJECTIVE: This study aimed to identify the differences in knowledge and attitude toward OSA between medical and dental practitioners working in North-Eastern Peninsular Malaysia. METHODS: A comparative cross-sectional study was performed from February 2020 to February 2021. A total of fifty-two medical practitioners and fifty-two dental practitioners working at university-based outpatient clinics, government health clinics, and oral health clinics located in Kelantan State of Malaysia participated in the study, and data were collected by the structured questionnaire including sociodemographic inquiry and OSAKA questionnaire by non-probability stratified random sampling. The Mann-Whitney U test was used to compare knowledge and attitude scores between the two groups. RESULTS: The mean age of the respondents was 34.6 years. The current study shows that 92.3% of medical doctors and 96.1% of dental doctors were able to correctly answer the question "Most of the patients with OSA snore" a significant finding in our study. Only 1% of medical professionals could answer seventeen questions correctly with a median score of 11, and only 1% of dental professionals could answer sixteen questions correctly with a median score of 9. None of them could provide an accurate answer to all the knowledge questions. Medical and dental practitioners exhibited different knowledge levels on OSA (z- statistics=-4.39, U = 827.00 with p <  0.05, and effect size, r = 0.61). However, no significant differences were found in total knowledge score by gender (p-value>0.05), ethnicity (p-value>0.05), total service years (p-value>0.05), and training attended. In addition, significant differences in attitude levels between medical and dental practitioners have been observed (z-statistics=-3.42, U = 725.00 with p <  0.05, and effect size, r = 0.47). Nevertheless, no significant differences have been seen in total attitude score by ethnicity (p-value >  0.05), total service years (p-value >  0.05), attending training on OSA (p-value >  0.05), and professional status (p-value >  0.05) except gender (p-value <  0.05). CONCLUSION: A Significant difference is evident concerning knowledge and attitude toward OSA diagnosis and management between medical and dental practitioners working in North-Eastern Peninsular Malaysia. Medical practitioners in this study recorded a higher knowledge and attitude score compared to dental practitioners.

4.
Acta Pharm Sin B ; 14(4): 1864-1877, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38572114

RESUMO

Small molecule drugs play a pivotal role in the arsenal of anticancer pharmacological agents. Nonetheless, their small size poses a challenge when directly visualizing their localization, distribution, mechanism of action (MOA), and target engagement at the subcellular level in real time. We propose a strategy for developing triple-functioning drug beacons that seamlessly integrate therapeutically relevant bioactivity, precise subcellular localization, and direct visualization capabilities within a single molecular entity. As a proof of concept, we have meticulously designed and constructed a boronic acid fluorescence drug beacon using coumarin-hemicyanine (CHB). Our CHB design includes three pivotal features: a boronic acid moiety that binds both adenosine triphosphate (ATP) and adenosine diphosphate (ADP), thus depleting their levels and disrupting the energy supply within mitochondria; a positively charged component that targets the drug beacon to mitochondria; and a sizeable conjugated luminophore that emits fluorescence, facilitating the application of structured illumination microscopy (SIM). Our study indicates the exceptional responsiveness of our proof-of-concept drug beacon to ADP and ATP, its efficacy in inhibiting tumor growth, and its ability to facilitate the tracking of ADP and ATP distribution around the mitochondrial cristae. Furthermore, our investigation reveals that the micro-dynamics of CHB induce mitochondrial dysfunction by causing damage to the mitochondrial cristae and mitochondrial DNA. Altogether, our findings highlight the potential of SIM in conjunction with visual drug design as a potent tool for monitoring the in situ MOA of small molecule anticancer compounds. This approach represents a crucial advancement in addressing a current challenge within the field of small molecule drug discovery and validation.

5.
Heart Vessels ; 39(7): 597-604, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38507055

RESUMO

BACKGROUND: This study was conducted to investigate the incidence of deep venous thrombosis (DVT), outcomes and its characteristics in patients with chronic heart failure (CHF) in a retrospective setting. OUTCOMES: Patients died of cardiac shock or acute exacerbation of heart failure (HF), admitted to intensive care unit (ICU) due to acute exacerbation of HF, patients decided to withdraw treatment and return home due to acute exacerbation of HF. METHODS: From January 2015 to June 2022, we admitted 359 patients diagnosed with CHF, and lower limb ultrasonography was performed for the examination of DVT after admission. The incidence of DVT was recorded and patients with known risk factors of VTE were identified and excluded after incidence of DVT was calculated. Patients' clinical data were then collected. RESULTS: The occurrence of DVT was 10.0% (36/359), as calf intramuscular vein thrombosis was the main constitution (n = 28, 75%). DVT patients with other factors (carcinoma, surgery, stroke, previous history of DVT) constituted a considerable part (33.3%, 12/36). Age, history of Diabetes Mellitus (DM), levels of DDi (D-Dimer), levels of alanine transferase (ALT) and left ventricular end-diastolic diameter (LVEDd) were independent predictors or risk factors of DVT in CHF patients, while chronic kidney disease (CKD) stage 1-4, white blood cell (WBC) and direct oral anticoagulant (DOAC) were protective factors. Incidence of DVT was correlated with a poor outcome of CHF patients (Pearson Chi-Square test, Value 19.612, P < 0.001). CONCLUSIONS: In this retrospective study, incidence of DVT was found to be relatively high among hospitalized CHF patients, while patients with DVT was associated with a poor prognosis.


Assuntos
Insuficiência Cardíaca , Hospitalização , Trombose Venosa , Humanos , Masculino , Insuficiência Cardíaca/epidemiologia , Insuficiência Cardíaca/diagnóstico , Feminino , Incidência , Trombose Venosa/epidemiologia , Trombose Venosa/diagnóstico , Trombose Venosa/diagnóstico por imagem , Estudos Retrospectivos , Idoso , Fatores de Risco , Hospitalização/estatística & dados numéricos , Pessoa de Meia-Idade , Doença Crônica , Idoso de 80 Anos ou mais , Extremidade Inferior/irrigação sanguínea , China/epidemiologia
6.
Hand (N Y) ; : 15589447231223775, 2024 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-38243624

RESUMO

BACKGROUND: The extent of injury in partially lacerated tendons has conventionally been expressed as a percentage of the total tendon, to justify surgical repair. We propose a more objective method to estimate the cross-sectional area of the remnant intact tendon and to determine if the remaining tendon fibers can withstand the tensile forces of early active mobilization against resistance. METHODS: The study was done on 20 cadaveric specimens, which were randomly assigned to receive a laceration of 25%, 50%, or 75% of the measured transverse tendon diameter. The circumference of the remaining intact portion of the partially lacerated tendon was measured and converted using a formula to determine the derived cross-sectional area (D-CSA). These D-CSA values were then validated by comparing them to digitally measured cross-sectional areas using a computer software program (computer-measured cross-sectional area, C-CSA). In addition, the ultimate tensile strength (UTS) of these partially lacerated tendons was analyzed to determine if a threshold exists beyond which surgical repair of a partially lacerated tendon is indicated. RESULTS: We found that the D-CSAs matched moderately with C-CSAs, with 0.622 of Pearson correlation coefficient. The UTSs of tendons with CSAs above 8 mm in circumference were consistently above 150 N. CONCLUSION: Measurement of the circumference of the partially lacerated tendon to obtain the D-CSA could be an accurate and practical method to benchmark residual tendon strength in the management of partially lacerated tendons.

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