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1.
Front Microbiol ; 15: 1392134, 2024.
Article in English | MEDLINE | ID: mdl-38741738

ABSTRACT

Methicillin-resistant Staphylococcus aureus (MRSA) has been recognized in hospitals, community and livestock animals and the epidemiology of MRSA is undergoing a major evolution among humans and animals in the last decade. This study investigated the prevalence of MRSA isolates from ground pork, retail whole chicken, and patient samples in Hanzhong, China. The further characterization was performed by antimicrobial susceptibility testing and in-depth genome-based analysis to identify the resistant determinants and their phylogenetic relationship. A total of 93 MRSA isolates were recovered from patients (n = 67) and retail livestock products (n = 26) in Hanzhong, China. 83.9% (78/93) MRSA isolates showed multiple drug resistant phenotype. Three dominant livestock-associated methicillin-resistant Staphylococcus aureus (LA-MRSA) sequence types were identified: ST59-t437 (n = 47), ST9-t899 (n = 10) and ST398 (n = 7). There was a wide variation among sequence types in the distribution of tetracycline-resistance, scn-negative livestock markers and virulence genes. A previous major human MRSA ST59 became the predominant interspecies MRSA sequence type among humans and retail livestock products. A few LA-MRSA isolates from patients and livestock products showed close genetic similarity. The spreading of MRSA ST59 among livestock products deserving special attention and active surveillance should be enacted for the further epidemic spread of MRSA ST59 in China. Data generated from this study will contribute to formulation of new strategies for combating spread of MRSA.

2.
J Formos Med Assoc ; 2024 May 07.
Article in English | MEDLINE | ID: mdl-38719675

ABSTRACT

BACKGROUND: Whether adjuvant chemotherapy should be different for patients with stage II and III gastric cancer is unknown. METHODS: We retrospectively analyzed the effects of adjuvant chemotherapy on the outcomes of 140 and 256 patients with stage II and III gastric cancer, respectively, between January 2008 and December 2018. Chemotherapies were stratified as fluoropyrimidine plus platinum versus fluoropyrimidine alone, tegafur/gimeracil/octeracil (S-1)-containing versus non-S-1-containing regimens, and S-1 plus cisplatin versus S-1 alone. RESULTS: The median age of patients was 67.0 (range 24.6-98.8) years. With a median follow-up of 105 months, recurrence occurred in 32 (22.9%) and 130 (50.8%) patients with stage II and III disease, respectively. Adjuvant chemotherapy was administered as fluoropyrimidine monotherapy to 68 (48.6%) and 73 (28.5%) patients, fluoropyrimidine plus platinum to 9 (6.4%) and 104 (40.6%) patients, and none to 63 (45.0%) and 79 (30.9%) patients with stage II and III gastric cancer, respectively. Doublet chemotherapy was associated with longer disease-free survival (DFS) (26.5 vs. 15.2 months, P = 0.001) and overall survival (OS) (41.2 vs. 22.0 months, P < 0.001) than fluoropyrimidine monotherapy for stage IIIB-IIIC disease. Furthermore, S-1-containing regimens prolonged DFS (57.4 vs. 21.9 months, P = 0.044) and OS (81.4 vs. 28.6 months, P = 0.023) compared with non-S-1-containing chemotherapy in stage III disease. CONCLUSION: Although fluoropyrimidine monotherapy is feasible for stage II-IIIA disease, doublet chemotherapy is significantly associated with longer survival than monotherapy for stage IIIB-IIIC disease. S-1-containing regimens might lead to longer survival than non-S-1-containing chemotherapy in stage III gastric cancer.

4.
Heliyon ; 10(9): e30488, 2024 May 15.
Article in English | MEDLINE | ID: mdl-38737264

ABSTRACT

Salvia miltiorrhiza Bunge (SM) is a widespread herbal therapy for myocardial ischemia (MI). Nevertheless, the therapeutic signaling networks of SM extract on MI is yet unknown. Emerging evidences suggested that alterations in cardiac metabolite influences host metabolism and accelerates MI progression. Herein, we employed an isoproterenol (ISO)-induced acute myocardial ischemia (AMI) rat model to confirm the pharmacological effects of SM extract (0.8, 0.9, 1.8 g/kg/day) via assessment of the histopathological alterations that occur within the heart tissue and associated cytokines; we also examined the underlying SM extract-mediated signaling networks using untargeted metabolomics. The results indicated that 25 compounds with a relative content higher than 1 % in SM aqueous extract were identified using LC-MS/MS analysis, which included salvianolic acid B, lithospermic acid, salvianolic acid A, and caffeic acid as main components. An in vivo experiment showed that pretreatment with SM extract attenuated ISO-induced myocardial injury, shown as decreased myocardial ischemic size, transformed electrocardiographic, histopathological, and serum biochemical aberrations, reduced levels of proinflammatory cytokines, inhibited oxidative stress (OS), and reversed the trepidations of the cardiac tissue metabolic profiles. Metabolomics analysis shows that the levels of 24 differential metabolites (DMs) approached the same value as controls after SM extract therapy, which were primarily involved in histidine; alanine, aspartate, and glutamate; glycerophospholipid; and glycine, serine, and threonine metabolisms through metabolic pathway analysis. Correlation analysis demonstrated that the levels of modulatory effects of SM extract on the inflammation and OS were related to alterations in endogenous metabolites. Overall, SM extract demonstrated significant cardioprotective effects in an ISO-induced AMI rat model, alleviating myocardial injury, inflammation and oxidative stress, with metabolomics analysis indicating potential therapeutic pathways for myocardial ischemia.

5.
Se Pu ; 42(5): 487-493, 2024 Apr 08.
Article in Chinese | MEDLINE | ID: mdl-38736393

ABSTRACT

The pharmaceutical analysis course is a three-dimensional knowledge network that connects several courses to form a new comprehensive knowledge node involving a large knowledge system and flexible knowledge structure. In this course, the subject of chromatography covers a wide range of topics. However, because accurate content is challenging to present, the teaching effect of this subject is poor. In this work, we sought to achieve the educational purpose of establishing morality and cultivating talent, as well as the goal of training highly skilled professionals, by taking the teaching of chromatography in the pharmaceutical analysis course as an example of transforming scientific research results into teaching resources. The resources obtained are integrated into the teaching process to provide innovative and scientific research ideas to students with the aim of not only helping them understand and master technical knowledge but also exercise their ability to raise and solve problems. Furthermore, we expound on how to introduce scientific development frontiers and formulate scientific problems through curriculum design. We also describe how our strategy can promote the teaching effect and achieve teaching objectives. Based on the characteristics of rapid knowledge update and equal emphasis on theory and practice in pharmaceutical analysis, the course is designed by introducing new advances in scientific development, formulating scientific problems, and adopting question- and problem-based learning methods for teaching. The teaching effect is then evaluated through diversified assessment, student feedback, and self-evaluation. The results show that the transformation of scientific research results into teaching resources plays a significant role in stimulating students' interest in learning, improving students' ability to solve problems, and achieving curriculum objectives, all of which greatly improve the teaching effect.


Subject(s)
Teaching , Chromatography , Curriculum , Humans
7.
Cureus ; 16(3): e55930, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38601389

ABSTRACT

BACKGROUND: Persistent human papillomavirus (HPV) infection is the primary cause of cervical cancer. However, this can be prevented through vaccination and screening. This study aimed to clarify the relationship between behavior, knowledge, and attitude toward cervical cancer and regular screening and HPV infection among women in Lueyang County. METHODS: Women who underwent cervical cancer screening at the outpatient department of a maternal and child health center between September and December 2021 were invited to participate. In total, 2,303 women completed the questionnaire. Women who underwent regular or irregular screening were 1:1 matched for age. Differences in knowledge of HPV and attitudes toward HPV vaccination among different populations were assessed. Logistic regression analysis was performed to identify the factors influencing HPV infection. RESULTS:  In total, 417 pairs of women who underwent regular and irregular screening were successfully matched. Multivariate logistic regression results indicated that age is a risk factor for HPV infection (OR=1.056 95%CI: [1.031 1.082]), while regular screening acts as a protective factor against HPV infection (OR=0.174 95%CI: [0.117 0.259]). Additionally, regular screening was associated with a higher level of knowledge about HPV among women compared to those who did not undergo regular screening (p<0.001). CONCLUSIONS:  Women in Lueyang County have low levels of knowledge regarding HPV and cervical cancer. Regular screening is a protective factor against HPV infection. The regular screening group demonstrates a higher level of HPV knowledge compared with the irregular screening group. These findings highlight the importance of regular screening and the need to strengthen public health education.

8.
Eur J Med Chem ; 271: 116401, 2024 May 05.
Article in English | MEDLINE | ID: mdl-38640870

ABSTRACT

Methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant Enterococci (VRE) cause more than 100,000 deaths each year, which need efficient and non-resistant antibacterial agents. SAR analysis of 162 flavonoids from the plant in this paper suggested that lipophilic group at C-3 was crucial, and then 63 novel flavonoid derivatives were designed and total synthesized. Among them, the most promising K15 displayed potent bactericidal activity against clinically isolated MRSA and VRE (MICs = 0.25-1.00 µg/mL) with low toxicity and high membrane selectivity. Moreover, mechanism insights revealed that K15 avoided resistance by disrupting biofilm and targeting the membrane, while vancomycin caused 256 times resistance against MRSA, and ampicillin caused 16 times resistance against VRE by the same 20 generations inducing. K15 eliminated residual bacteria in mice skin MRSA-infected model (>99 %) and abdominal VRE-infected model (>92 %), which was superior to vancomycin and ampicillin.


Subject(s)
Anti-Bacterial Agents , Flavonoids , Methicillin-Resistant Staphylococcus aureus , Microbial Sensitivity Tests , Vancomycin-Resistant Enterococci , Methicillin-Resistant Staphylococcus aureus/drug effects , Flavonoids/pharmacology , Flavonoids/chemistry , Flavonoids/chemical synthesis , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/chemistry , Anti-Bacterial Agents/chemical synthesis , Vancomycin-Resistant Enterococci/drug effects , Animals , Mice , Structure-Activity Relationship , Molecular Structure , Dose-Response Relationship, Drug , Staphylococcal Infections/drug therapy , Humans
9.
World J Clin Cases ; 12(11): 1996-1999, 2024 Apr 16.
Article in English | MEDLINE | ID: mdl-38660554

ABSTRACT

Diabetes comprises a group of metabolic diseases characterized by hyperglycemia stemming from various factors. Current diabetes management primarily focuses on blood glucose control, yet it is inherently progressive, necessitating increased reliance on exogenous blood glucose control methods over time. Therefore, there is an urgent need to explore novel intervention strategies addressing both diabetes and its complications. The human intestinal microbiota, often referred to as the "second genome", exhibits significant diversity and plays a pivotal role in insulin resistance, glucose and lipid metabolism, and inflammatory response. Notably, Li and Guo have elucidated the involvement of intestinal flora in the pathogenesis of type 2 diabetes mellitus (T2DM) and proposed a novel therapeutic approach targeting intestinal microbes. This advancement enhances our comprehension of the multifaceted and multi-target regulation of T2DM by intestinal microflora, thereby offering fresh avenues for understanding its pathogenesis and clinical management. This letter briefly summarizes the role of intestinal flora in T2DM based on findings from animal experiments and clinical studies. Additionally, it discusses the potential clinical applications and challenges associated with targeting intestinal flora as therapeutic interventions.

10.
J Am Geriatr Soc ; 2024 Apr 25.
Article in English | MEDLINE | ID: mdl-38662854

ABSTRACT

BACKGROUND: Clinical practice guidelines recommend early serum electrolyte monitoring when starting antidepressants in older adults due to the increased risk of hyponatremia. It is unclear whether this monitoring improves outcomes. METHODS: Population-based, retrospective cohort study of Ontario adults aged ≥66 years who initiated therapy with a selective serotonin reuptake inhibitor (SSRI) or selective norepinephrine reuptake inhibitor (SNRI) between April 1, 2013, and January 31, 2020. The index date was the date of the first such prescription, and the exposure of interest was serum electrolyte measurement during the subsequent 7 days. The primary outcome was any emergency department or hospital admission with hyponatremia within 8-60 days of antidepressant initiation. Poisson regression models compared individuals who had versus did not have their serum electrolytes tested in the week following SSRI/SNRI initiation, weighting by propensity score-based overlap weights. RESULTS: Among the 420,085 patients aged ≥66 years initiating treatment with an SSRI/SNRI, 26,808 (6.4%) had serum electrolytes measured in the subsequent 7 days and 6109 (1.5%) subsequently presented to hospital with hyponatremia. The time from drug initiation to hospitalization varied (median 29, interquartile range [IQR] 17-44 days), and the median sodium concentration measured in the community (136, IQR 133-138 mmol/L) was marginally higher than those at the time of hospitalization (132, IQR 130-134 mmol/L). Patients who underwent electrolyte testing in the week following SSRI/SNRI treatment were more likely to attend an emergency department (ED) or hospital with hyponatremia within 8-60 days relative to those who did not (relative risk = 2.31, 95% confidence interval: 2.16-2.46). CONCLUSIONS: Testing serum electrolytes in the week after starting an SSRI/SNRI is not associated with a reduced risk of a hospital visit with hyponatremia. These findings do not support current guidelines recommending routine electrolyte monitoring.

11.
ACS Omega ; 9(14): 16063-16070, 2024 Apr 09.
Article in English | MEDLINE | ID: mdl-38617677

ABSTRACT

The efficient and clean utilization of urban waste can substitute for partial fossil fuels and reduce total carbon emissions. Fuel combustion is divided into three stages. Before the fire, the fuel is put into the furnace to reach the preparation stage of the fire temperature, the combustion stage takes place after the ignition temperature is reached, and finally, the combustion is completed. This article employs numerical simulation methods to comprehensively study the effects of various factors on the combustion characteristics of waste in a mechanical grate incinerator, including the inclination angle of the front arch, fuel properties, height of the front and rear arches, air distribution methods, and speed of the grate chain rotation. The results indicate that when the rear arch angle is set at 25°, the airflow distribution within the furnace is uniform and the high-temperature flue gas exhibits an ideal "L" shaped flow, achieving favorable characteristics of airflow distribution inside the furnace. With this structure, the airflow from the rear arch can adequately penetrate deep into the front arch area, thereby forming an efficient T-shaped combustion flame.

12.
J Ethnopharmacol ; 329: 118177, 2024 Apr 10.
Article in English | MEDLINE | ID: mdl-38604510

ABSTRACT

ETHNOPHARMACOLOGICAL RELEVANCE: Corydalis decumbens (Thunb.) Pers. was used as stasis-eliminating medicine traditionally to treat cardiovascular disease potentially attributed to its antithrombotic effect, but lack of pharmacological research on it. AIM OF THE STUDY: To investigate the antithrombotic effect of C. decumbens and its preliminary mechanism. MATERIALS AND METHODS: A carrageenan-induced mouse thrombus model and adenosine diphosphate stimulated platelet aggregation of rabbits were used to confirm the inhibitory effect of C. decumbens extract and compounds on thrombosis in vivo. Then, H2O2-induced human umbilical vein endothelial cells (HUVECs) injury model was further adopted to verify the effects of bioactive compounds in vitro. Moreover, in silico network pharmacology analyses and molecular docking were performed to predict the underlying mechanisms, targets, and pathways, and which were further confirmed through western blotting assay. RESULTS: The administration of total extract (TE), total alkaloids (TA) and tetrahydropalmatine (TET) resulted in a significant reduction in black tail thrombus and congestion, along with a decreasing in platelet aggregation of rabbits. A superior antithrombotic effect indicated the bioactive fraction, and then the isolated bioactive compounds, TET and protopine (PRO) increased cell survival, and decreased reactive oxygen species (ROS) and lactate dehydrogenase (LDH) release in H2O2-induced HUVECs injury model. Moreover, the two alkaloids targeted 33 major proteins and influenced 153 pathways in network pharmacology prediction. Among these, HSP90AA1, COX-2, NF-κB/p65, MMP1 and HIF-1α were the key proteins and PI3K-Akt emerged as the major signaling pathway. Further western blotting results supported that five key proteins were downregulated by the two bioactive compounds in H2O2-stimulated HUVECs model. CONCLUSION: C. decumbens exerted protective effect on thrombosis through inhibiting PI3K-Akt pathway and related key proteins, which supported the traditional use and presented potential antithrombotic alkaloids for further investigation.

13.
Plants (Basel) ; 13(8)2024 Apr 11.
Article in English | MEDLINE | ID: mdl-38674483

ABSTRACT

Olibanum, a golden oleo-gum resin from species in the Boswellia genus (Burseraceae family), is a famous traditional herbal medicine widely used around the world. Previous phytochemical studies mainly focused on the non-polar fractions of olibanum. In this study, nine novel diterpenoids, boswellianols A-I (1-9), and three known compounds were isolated from the polar methanolic fraction of the oleo-gum resin of Boswellia carterii. Their structures were determined through comprehensive spectroscopic analysis as well as experimental and calculated electronic circular dichroism (ECD) data comparison. Compound 1 is a novel diterpenoid possessing an undescribed prenylmaaliane-type skeleton with a 6/6/3 tricyclic system. Compounds 2-4 were unusual prenylaromadendrane-type diterpenoids, and compounds 5-9 were new highly oxidized cembrane-type diterpenoids. Compounds 1 and 5 showed significant transforming growth factor ß (TGF-ß) inhibitory activity via inhibiting the TGF-ß-induced phosphorylation of Smad3 and the expression of fibronectin and N-cadherin (the biomarker of the epithelial-mesenchymal transition) in a dose-dependent manner in LX-2 human hepatic stellate cells, indicating that compounds 1 and 5 should be potential anti-fibrosis agents. These findings give a new insight into the chemical constituents of the polar fraction of olibanum and their inhibitory activities on the TGF-ß/Smad signaling pathway.

14.
Pancreatology ; 2024 Mar 25.
Article in English | MEDLINE | ID: mdl-38565467

ABSTRACT

BACKGROUND/OBJECTIVES: Liposomal irinotecan plus 5-fluorouracil and leucovorin (nal-IRI + 5-FU/LV) provides survival benefits for metastatic pancreatic adenocarcinoma (mPDAC) refractory to gemcitabine-based treatment, mainly gemcitabine plus nab-paclitaxel (GA), in current practice. Gemcitabine plus S-1 (GS) is another commonly administered first-line regimen before nab-paclitaxel reimbursement; however, the efficacy and safety of nal-IRI + 5-FU/LV for mPDAC after failed GS treatment has not been reported and was therefore explored in this study. METHODS: In total, 177 patients with mPDAC received first-line GS or GA treatment, followed by second-line nal-IRI + 5-FU/LV treatment (identified from a multicenter retrospective cohort in Taiwan from 2018 to 2020); 85 and 92 patients were allocated to the GS and GA groups, respectively. Overall survival (OS), time-to-treatment failure (TTF), and adverse events were compared between the two groups. RESULTS: The baseline characteristics of the two groups were generally similar; however, a higher median age (67 versus 62 years, p < 0.001) and fewer liver metastases (52% versus 78%, p < 0.001) were observed in the GS versus GA group. The median OS was 15.0 and 15.9 months in the GS and GA groups, respectively (p = 0.58). The TTF (3.1 versus 2.8 months, p = 0.36) and OS (7.6 versus 6.7 months, p = 0.83) after nal-IRI treatment were similar between the two groups. More patients in the GS group developed mucositis during nal-IRI treatment (15% versus 4%, p = 0.02). CONCLUSIONS: The efficacy of second-line nal-IRI +5-FU/LV treatment was unaffected by prior S-1 exposure. GS followed by nal-IRI treatment is an alternative treatment sequence for patients with mPDAC.

15.
Cureus ; 16(4): e58081, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38616979

ABSTRACT

Purpose This study delves into the epidemiology of high-risk human papillomavirus (HR-HPV) infection and its link to precancerous lesions among perimenopausal (40-59 years) and elderly (60-65 years) women in a Chinese county with a notably high incidence of cervical cancer. By uniquely focusing on these age groups in underdeveloped regions, the research aims to offer novel strategies for the management and prevention of cervical cancer. It seeks to inform targeted interventions and public health policies that could significantly benefit women at heightened risk for HPV, addressing a critical gap in current prevention efforts in economically disadvantaged communities. Methods This observational study was conducted at the Maternal and Child Health and Family Planning Service Centre in Lueyang County, from September 2021 to January 2022. It assessed 2008 women aged 40-65 for HPV screening, with 342 undergoing further cytological examination. The study evaluated the prevalence of HPV infection across different age groups and risk categories. It utilized a questionnaire to collect participants' basic information, health behaviors, and other relevant data to analyze factors influencing HR-HPV infection. Statistical analyses comprised chi-square tests, trend analysis, logistic regression, and multiple imputation techniques to address missing data. Results The prevalence of HR-HPV infection among women aged 40-65 years in Lueyang County was 18.43%. Older women exhibited a higher incidence of HPV infection, abnormal ThinPrep Cytology Test (TCT) results (Shaanxi Fu'an Biotechnology Co. Ltd., Baoji City, China), and low/high-grade squamous intraepithelial lesions (LSIL/HSIL) (P<0.05). The most prevalent HR-HPV genotypes in the overall, perimenopausal, and elderly groups were HPV-52, -53, and -58; HPV-52, -53, and -16; and HPV-58, -52, and -53, respectively. The prevalent HR-HPV genotypes in the abnormal The Bethesda System (TBS) results were HPV-16, -52, -33, -58; -16, -52, -58; and-16, -33, and -52. HPV-16, -18, -33 prevalence increased with increasing lesion severity (P<0.05). In this study, factors affecting HR-HPV in the three age groups were found to be mainly related to sexual behavior and education level, including history of lower genital tract diseases, multiple pregnancies, contraceptive methods without tubal ligation, age at first marriage greater than 18 years, never washing the vulva after sex, abstinence from sex, education level of junior high school or above, and spouse's education level of high school or above. Conclusions These findings suggest that the elevated rate of abnormal TBS in the older age group may be attributed to the higher prevalence of persistent infection-prone HR-HPV genotypes (HPV-58, -52, and-53), multiple infections, and potent oncogenic HR-HPV genotypes (HPV-16 and -33). Additionally, the higher HR-HPV prevalence in older patients may be related to lower education attainment, reduced screening rate, and limited condom usage. Therefore, strategies targeting perimenopausal and older women should prioritize enhancing health awareness, increasing screening rates, and encouraging condom utilization.

16.
Environ Toxicol ; 39(6): 3710-3720, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38511855

ABSTRACT

Tryptanthrin, an alkaloid applied in traditional Chinese medicine, exhibits a variety of pharmacological activities. This study aimed to investigate the anti-tumor activity of the tryptanthrin derivative (8-cyanoindolo[2,1-b]quinazoline-6,12-dione [CIQ]) in breast cancer cells. In both MDA-MB-231 and MCF-7 breast cancer cells, CIQ inhibited cell viability and promoted caspase-dependent apoptosis. At the concentration- and time-dependent ways, CIQ increased the levels of p-ERK, p-JNK, and p-p38 in breast cancer cells. We found that exposure to the JNK inhibitor or the ERK inhibitor partially reversed CIQ's viability. We also observed that CIQ increased reactive oxygen species (ROS) generation, and upregulated the phosphorylation and expression of H2AX. However, the pretreatment of the antioxidants did not protect the cells against CIQ's effects on cell viability and apoptosis, which suggested that ROS does not play a major role in the mechanism of action of CIQ. In addition, CIQ inhibited the invasion of MDA-MB-231 cells and decreased the expression of the prometastatic factors (MMP-2 and Snail). These findings demonstrated that the possibility of this compound to show promise in playing an important role against breast cancer.


Subject(s)
Antineoplastic Agents , Apoptosis , Breast Neoplasms , Cell Survival , Quinazolines , Reactive Oxygen Species , Humans , Quinazolines/pharmacology , Breast Neoplasms/drug therapy , Breast Neoplasms/pathology , Cell Survival/drug effects , Reactive Oxygen Species/metabolism , Apoptosis/drug effects , Antineoplastic Agents/pharmacology , Cell Line, Tumor , Female , MCF-7 Cells , MAP Kinase Signaling System/drug effects
17.
ACS Synth Biol ; 13(4): 1177-1190, 2024 Apr 19.
Article in English | MEDLINE | ID: mdl-38552148

ABSTRACT

The small ultrared fluorescent protein (smURFP) is a bright near-infrared (NIR) fluorescent protein (FP) that forms a dimer and binds its fluorescence chromophore, biliverdin, at its dimer interface. To engineer a monomeric NIR FP based on smURFP potentially more suitable for bioimaging, we employed protein design to extend the protein backbone with a new segment of two helices that shield the original dimer interface while covering the biliverdin binding pocket in place of the second chain in the original dimer. We experimentally characterized 13 designs and obtained a monomeric protein with a weak fluorescence. We enhanced the fluorescence of this designed protein through two rounds of directed evolution and obtained designed monomeric smURFP (DMsmURFP), a bright, stable, and monomeric NIR FP with a molecular weight of 19.6 kDa. We determined the crystal structures of DMsmURFP both in the apo state and in complex with biliverdin, which confirmed the designed structure. The use of DMsmURFP in in vivo imaging of mammalian systems was demonstrated. The backbone design-based strategy used here can also be applied to monomerize other naturally multimeric proteins with intersubunit functional sites.


Subject(s)
Bacterial Proteins , Biliverdine , Animals , Luminescent Proteins/metabolism , Biliverdine/chemistry , Microscopy, Fluorescence/methods , Bacterial Proteins/metabolism , Fluorescent Dyes , Mammals/metabolism
18.
Invest New Drugs ; 42(2): 221-228, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38441850

ABSTRACT

AbGn-107 is an antibody-drug conjugate directed against AG-7 antigen, a Lewis A-like glycol-epitope expressed in a variety of gastrointestinal (GI) malignancies. Based on promising antitumor activity of AbGn-107 in both in vitro and in vivo preclinical studies, we performed a GI cancer-specific Phase I trial. Standard 3 + 3 dose escalation was used evaluating intravenous doses ranging from 0.1 mg/kg every 4 weeks to 1.0 mg/kg every 2 weeks. Key eligibility included chemo-refractory locally advanced, recurrent, or metastatic gastric, colorectal, pancreatic, or biliary cancer, with ECOG PS 0-1; positive AG-7 expression was not required during dose escalation phase. Patients were treated until disease progression or unacceptable toxicity, with tumor assessments every 8 weeks. Primary objectives included safety and determination of maximum tolerated dose; secondary objectives included efficacy defined by objective response rate. Thirty-nine patients were enrolled across seven dose levels during dose escalation phase. Based on safety profile and pharmacokinetic data, 1.0 mg/kg Q2W was selected as the dose schedule for cohort expansion phase, in which an additional seven patients were enrolled. Median number of lines of prior therapy was 3 (range 1-7). AbGn-107 was generally well-tolerated, with infections, cytopenias, hyponatremia, fatigue, abdominal pain, and diarrhea representing the most common grade 3 or higher treatment-emergent adverse events. One subject achieved a partial response, while 18 (46.2%) achieved a best response of stable disease. Disease control lasting > 6 months was observed in 6 subjects (13.0%), including 4 of 15 (26.7%) treated at the highest dose level. AbGn-107 showed a reasonable safety profile and modest clinical activity in this highly pretreated patient population. Further evaluation is required to assess the clinical validity of AG-7 as a suitable antigen for therapeutic targeting. Clinical Trial information: NCT02908451.


Subject(s)
Gastrointestinal Neoplasms , Immunoconjugates , Humans , Immunoconjugates/adverse effects , Gastrointestinal Neoplasms/drug therapy , Maximum Tolerated Dose
19.
Orphanet J Rare Dis ; 19(1): 123, 2024 Mar 14.
Article in English | MEDLINE | ID: mdl-38486238

ABSTRACT

BACKGROUND: Pathogenic missense variants in the dystrophin (DMD) gene are rarely reported in dystrophinopathies. Most DMD missense variants are of uncertain significance and their pathogenicity interpretation remains complicated. We aimed to investigate whether DMD missense variants would cause aberrant splicing and re-interpret their pathogenicity based on mRNA and protein studies. METHODS: Nine unrelated patients who had an elevated serum creatine kinase level with or without muscle weakness were enrolled. They underwent a detailed clinical, imaging, and pathological assessment. Routine genetic testing and muscle-derived mRNA and protein studies of dystrophin and sarcoglycan genes were performed in them. RESULTS: Three of the 9 patients presented with a Duchenne muscular dystrophy (DMD) phenotype and the remaining 6 patients had a suspected diagnosis of Becker muscular dystrophy (BMD) or sarcoglycanopathy based on their clinical and pathological characteristics. Routine genetic testing detected only 9 predicted DMD missense variants in them, of which 6 were novel and interpreted as uncertain significance. Muscle-derived mRNA studies of sarcoglycan genes didn't reveal any aberrant transcripts in them. Dystrophin mRNA studies confirmed that 3 predicted DMD missense variants (c.2380G > C, c.4977C > G, and c.5444A > G) were in fact splicing and frameshift variants due to aberrant splicing. The 9 DMD variants were re-interpreted as pathogenic or likely pathogenic based on mRNA and protein studies. Therefore, 3 patients with DMD splicing variants and 6 patients with confirmed DMD missense variants were diagnosed with DMD and BMD, respectively. CONCLUSION: Our study highlights the importance of muscle biopsy and aberrant splicing for clinical and genetic interpretation of uncertain DMD missense variants.


Subject(s)
Dystrophin , Muscular Dystrophy, Duchenne , Humans , Dystrophin/genetics , Muscular Dystrophy, Duchenne/genetics , Mutation, Missense/genetics , RNA, Messenger/genetics , Sarcoglycans/genetics
20.
Sci Total Environ ; 924: 171657, 2024 May 10.
Article in English | MEDLINE | ID: mdl-38490413

ABSTRACT

Global occurrences of foodborne disease outbreaks have been documented, involving fresh agricultural produce contaminated by various pathogens. This contamination can occur at any point in the supply chain. However, studies on the prevalence of total coliforms, Salmonella and microbial diversity in vegetable and associated environments are limited. This study aimed to assess 1) the number of total coliforms (n = 299) and diversity of microbial communities (n = 52); 2) the prevalence, antibiotic susceptibility, genomic characteristics, and potential transmission relationships of Salmonella in soil-irrigation water-vegetable system (n = 506). Overall, 84.28 % samples were positive to total coliforms, with most frequently detected in soil (100 %), followed by irrigation water (79.26 %) and vegetables (62.00 %). A seasonal trend in coliform prevalence was observed, with significantly higher levels in summer (P < 0.05). Detection rates of Salmonella in soil, vegetable and irrigation water were 2.21 %, 4.74 % and 9.40 %. Fourteen serotypes and sequence types (STs) were respectively annotated in 56 Salmonella isolates, ST13 S. Agona (30.36 %, 17/56), ST469 S. Rissen (25.00 %, 14/56), and ST36 S. Typhimurium (12.50 %, 7/56) were dominant serotypes and STs. Thirty-one (55.36 %) isolates were multi-drug resistant, and the resistance was most frequently found to ampicillin (55.36 %, 31/56), followed by to sulfamethoxazole (51.79 %, 29/56) and tetracycline (50.00 %, 28/56). The genomic characteristics and antibiotic resistance patterns of Salmonella isolates from soil, vegetables, and irrigation water within a coherent geographical locale exhibited remarkable similarities, indicating Salmonella may be transmitted among these environments or have a common source of contamination. Microbial alpha diversity indices in soil were significantly higher (P < 0.05) than that in vegetable and irrigation water. The microbial phylum in irrigation water covered that in the vegetable, demonstrating a significant overlap in the microbial communities between the vegetables and the irrigation water.


Subject(s)
Soil , Vegetables , Agricultural Irrigation , Salmonella , Anti-Bacterial Agents , Water , Microbial Sensitivity Tests
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