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1.
BMC Public Health ; 24(1): 693, 2024 Mar 04.
Article in English | MEDLINE | ID: mdl-38438990

ABSTRACT

BACKGROUND: Second-hand smoking (SHS) increases the risk of chronic disease in adults and poses a serious health threat to children. Mass media campaigns are instrumental in raising awareness and reducing SHS exposure. There is a need to identify recent SHS mass media campaigns and assess their sustainability in terms of knowledge, attitudes, and behavioural changes. This systematic review summarises the characteristics and outcomes of mass media campaigns on SHS prevention. METHODS: PubMed, Embase, Web of Science, and grey literature were searched in November 2022 for SHS campaigns implemented between 2016 and 2022. The eligibility criteria included campaigns on the dangers or effects of SHS with any target group, dissemination medium, study design, or language. The database search identified 1,413 peer-reviewed titles, of which 82 full-texts were screened, with 14 meeting the eligibility criteria. The grey literature search identified 9,807 sources, of which 61 were included. We extracted data on the campaign characteristics, metrics, and smoking-related outcomes. The JBI critical appraisal tool was used to assess the risk of bias of the included studies. RESULTS: We found 73 SHS campaigns conducted between 2002 and 2022, across 50 countries. The campaigns reached 378 million people. The reported recall rates range from 8 to 76%. Of the 11 studies that reported smoking-related outcomes, 10 reported increased knowledge in understanding SHS risks (73-85%), five reported an increased prevalence of smoke-free homes, and two reported an increase in number of participants persuading others to quit smoking. Two studies reported a decrease in overall smoking, whereas three studies observed a reduction in smoking in the presence of children. CONCLUSION: The available data provide some support for the effectiveness of SHS campaigns in reducing smoking behaviours in homes and around children. However, the certainty of evidence was low due to the lack of a control group and the substantial heterogeneity in the outcomes assessed. Future campaigns need comprehensive evaluation and reporting to reduce publication bias.


Subject(s)
Mass Media , Tobacco Smoke Pollution , Humans , Smoking/epidemiology , Tobacco Smoke Pollution/adverse effects , Tobacco Smoke Pollution/prevention & control
2.
Cancer Immunol Immunother ; 73(1): 10, 2024 Jan 17.
Article in English | MEDLINE | ID: mdl-38231444

ABSTRACT

The antigen processing machinery (APM) components needed for a tumor cell to present an antigen to a T cell are expressed at low levels in solid tumors, constituting an important mechanism of immune escape. More than most other solid tumors, head and neck squamous cell carcinoma (HNSCC) cells tend to have low APM expression, rendering them insensitive to immune checkpoint blockade and most other forms of immunotherapy. In HNSCC, this APM deficiency is largely driven by high levels of EGFR and SHP2, leading to low expression and activation of STAT1; however, recent studies suggest that p53, which is often mutated in HNSCCs, may also play a role. In the current study, we aimed to investigate the extent to which STAT1 and p53 individually regulate APM component expression in HNSCC cells. We found that in cells lacking functional p53, APM expression could still be induced by interferon-gamma or DNA-damaging chemotherapy (cisplatin) as long as STAT1 expression remained intact; when both transcription factors were knocked down, APM component expression was abolished. When we bypassed these deficient pathways by rescuing the expression of NLRC5, APM expression was also restored. These results suggest that dual loss of functional STAT1 and p53 may render HNSCC cells incapable of processing and presenting antigens, but rescue of downstream NLRC5 expression may be an attractive strategy for restoring sensitivity to T cell-based immunotherapy.


Subject(s)
Antigen Presentation , Head and Neck Neoplasms , Humans , Squamous Cell Carcinoma of Head and Neck , Tumor Suppressor Protein p53/genetics , Head and Neck Neoplasms/genetics , Cisplatin , STAT1 Transcription Factor/genetics , Intracellular Signaling Peptides and Proteins
3.
Clin Kidney J ; 17(1): sfad304, 2024 Jan.
Article in English | MEDLINE | ID: mdl-38213491

ABSTRACT

Background: Intradialytic hypotension (IDH) is a common hemodialysis complication causing adverse outcomes. Despite the well-documented associations of ambient temperatures with fluid removal and pre-dialysis blood pressure (BP), the relationship between ambient temperature and IDH has not been adequately studied. Methods: We conducted a cohort study at a tertiary hospital in southern Taiwan between 1 January 2016 and 31 October 2021. The 24-h pre-hemodialysis mean ambient temperature was determined using hourly readings from the weather station closest to each patient's residence. IDH was defined using Fall40 [systolic BP (SBP) drop of ≥40 mmHg] or Nadir90/100 (SBP <100 if pre-dialysis SBP was ≥160, or SBP <90 mmHg). Multivariate logistic regression with generalizing estimating equations and mediation analysis were utilized. Results: The study examined 110 400 hemodialysis sessions from 182 patients, finding an IDH prevalence of 11.8% and 10.4% as per the Fall40 and Nadir90/100 criteria, respectively. It revealed a reverse J-shaped relationship between ambient temperature and IDH, with a turning point around 27°C. For temperatures under 27°C, a 4°C drop significantly increased the odds ratio of IDH to 1.292 [95% confidence interval (CI) 1.228 to 1.358] and 1.207 (95% CI 1.149 to 1.268) under the Fall40 and Nadir90/100 definitions, respectively. Lower ambient temperatures correlated with higher ultrafiltration, accounting for about 23% of the increased IDH risk. Stratified seasonal analysis indicated that this relationship was consistent in spring, autumn and winter. Conclusion: Lower ambient temperature is significantly associated with an increased risk of IDH below the threshold of 27°C, irrespective of the IDH definition. This study provides further insight into environmental risk factors for IDH in patients undergoing hemodialysis.

4.
Zhongguo Zhong Yao Za Zhi ; 48(11): 2931-2939, 2023 Jun.
Article in Chinese | MEDLINE | ID: mdl-37381953

ABSTRACT

The U6 promoter is an important element driving sgRNA transcription in the CRISPR/Cas9 system. Seven PqU6 promo-ter sequences were cloned from the gDNA of Panax quinquefolium, and the transcriptional activation ability of the seven promoters was studied. In this study, seven PqU6 promoter sequences with a length of about 1 300 bp were cloned from the adventitious roots of P. quinquefolium cultivated for 5 weeks. Bioinformatics tools were used to analyze the sequence characteristics of PqU6 promoters, and the fusion expression vectors of GUS gene driven by PqU6-P were constructed. Tobacco leaves were transformed by Agrobacterium tumefaciens-mediated method for activity detection. The seven PqU6 promoters were truncated from the 5'-end to reach 283, 287, 279, 289, 295, 289, and 283 bp, respectively. The vectors for detection of promoter activity were constructed with GUS as a reported gene and used to transform P. quinquefolium callus and tobacco leaves. The results showed that seven PqU6 promoter sequences(PqU6-1P to PqU6-7P) were cloned from the gDNA of P. quinquefolium, with the length ranged from 1 246 bp to 1 308 bp. Sequence comparison results showed that the seven PqU6 promoter sequences and the AtU6-P promoter all had USE and TATA boxes, which are essential elements affecting the transcriptional activity of the U6 promoter. The results of GUS staining and enzyme activity test showed that all the seven PqU6 promoters had transcriptional activity. The PqU6-7P with a length of 1 269 bp had the highest transcriptional activity, 1.31 times that of the positive control P-35S. When the seven PqU6 promoters were truncated from the 5'-end(PqU6-1PA to PqU6-7PA), their transcriptional activities were different in tobacco leaves and P. quinquefolium callus. The transcriptional activity of PqU6-7PA promoter(283 bp) was 1.59 times that of AtU6-P promoter(292 bp) when the recipient material was P. quinquefolium callus. The findings provide more ideal endogenous U6 promoters for CRISPR/Cas9 technology in ginseng and other medicinal plants.


Subject(s)
Panax , Panax/genetics , Promoter Regions, Genetic , Agrobacterium tumefaciens/genetics , Computational Biology , Cloning, Molecular
5.
Nat Commun ; 14(1): 2102, 2023 04 13.
Article in English | MEDLINE | ID: mdl-37055393

ABSTRACT

Histopathologic assessment is indispensable for diagnosing colorectal cancer (CRC). However, manual evaluation of the diseased tissues under the microscope cannot reliably inform patient prognosis or genomic variations crucial for treatment selections. To address these challenges, we develop the Multi-omics Multi-cohort Assessment (MOMA) platform, an explainable machine learning approach, to systematically identify and interpret the relationship between patients' histologic patterns, multi-omics, and clinical profiles in three large patient cohorts (n = 1888). MOMA successfully predicts the overall survival, disease-free survival (log-rank test P-value<0.05), and copy number alterations of CRC patients. In addition, our approaches identify interpretable pathology patterns predictive of gene expression profiles, microsatellite instability status, and clinically actionable genetic alterations. We show that MOMA models are generalizable to multiple patient populations with different demographic compositions and pathology images collected from distinctive digitization methods. Our machine learning approaches provide clinically actionable predictions that could inform treatments for colorectal cancer patients.


Subject(s)
Colorectal Neoplasms , Multiomics , Humans , Colorectal Neoplasms/diagnosis , Colorectal Neoplasms/genetics , Mutation , Microsatellite Instability , Disease-Free Survival
6.
Nat Biomed Eng ; 6(3): 310-324, 2022 03.
Article in English | MEDLINE | ID: mdl-35241815

ABSTRACT

Immune checkpoint blockade (ICB) therapy does not benefit the majority of treated patients, and those who respond to the therapy can become resistant to it. Here we report the design and performance of systemically administered protease activity sensors conjugated to anti-programmed cell death protein 1 (αPD1) antibodies for the monitoring of antitumour responses to ICB therapy. The sensors consist of a library of mass-barcoded protease substrates that, when cleaved by tumour proteases and immune proteases, are released into urine, where they can be detected by mass spectrometry. By using syngeneic mouse models of colorectal cancer, we show that random forest classifiers trained on mass spectrometry signatures from a library of αPD1-conjugated mass-barcoded activity sensors for differentially expressed tumour proteases and immune proteases can be used to detect early antitumour responses and discriminate resistance to ICB therapy driven by loss-of-function mutations in either the B2m or Jak1 genes. Biomarkers of protease activity may facilitate the assessment of early responses to ICB therapy and the classification of refractory tumours based on resistance mechanisms.


Subject(s)
Immunoconjugates , Neoplasms , Animals , Disease Models, Animal , Humans , Mice , Peptide Hydrolases , Urinalysis
7.
Sci Adv ; 8(8): eabm7950, 2022 Feb 25.
Article in English | MEDLINE | ID: mdl-35196075

ABSTRACT

Simultaneous delivery of mRNA to multiple populations of antigen (Ag)-specific CD8+ T cells is challenging given the diversity of peptide epitopes and polymorphism of class I major histocompatibility complexes (MHCI). We developed Ag-presenting nanoparticles (APNs) for mRNA delivery using pMHCI molecules that were refolded with photocleavable peptides to allow rapid ligand exchange by UV light and site-specifically conjugated with a lipid tail for postinsertion into preformed mRNA lipid nanoparticles. Across different TCR transgenic mouse models (P14, OT-1, and Pmel), UV-exchanged APNs bound and transfected their cognate Ag-specific CD8+ T cells equivalent to APNs produced using conventionally refolded pMHCI molecules. In mice infected with PR8 influenza, multiplexed delivery of UV-exchanged APNs against three immunodominant epitopes led to ~50% transfection of a VHH mRNA reporter in cognate Ag-specific CD8+ T cells. Our data show that UV-mediated peptide exchange can be used to rapidly produce APNs for mRNA delivery to multiple populations of Ag-specific T cells in vivo.

8.
Adv Ther (Weinh) ; 4(8)2021 Aug.
Article in English | MEDLINE | ID: mdl-34541300

ABSTRACT

Adoptive T cell therapies are transforming the treatment of solid and liquid tumors, yet their widespread adoption is limited in part by the challenge of generating functional cells. T cell activation and expansion using conventional antigen-presenting cells (APCs) is unreliable due to the variable quality of donor-derived APCs. As a result, engineered approaches using nanomaterials presenting T cell activation signals are a promising alternative due to their ability to be robustly manufactured with precise control over stimulation cues. In this work, we design synthetic APCs that consist of liposomes surface-functionalized with peptide-major histocompatibility complexes (pMHC). Synthetic APCs selectively target and activate antigen-specific T cell populations to levels similar to conventional protocols using non-specific αCD3 and αCD28 antibodies without the need for costimulation signals. T cells treated with synthetic APCs produce effector cytokines and demonstrate cytotoxic activity when co-cultured with tumor cells presenting target antigen in vitro. Following adoptive transfer into tumor-bearing mice, activated cells control tumor growth and improve overall survival compared to untreated mice. Synthetic APCs could potentially be used in the future to improve the accessibility of adoptive T cell therapies by removing the need for conventional APCs during manufacturing.

9.
Adv Healthc Mater ; 10(15): e2100157, 2021 08.
Article in English | MEDLINE | ID: mdl-33887123

ABSTRACT

The clinical success of cancer immunotherapy is providing exciting opportunities for the development of new methods to detect and treat cancer more effectively. A new generation of biomaterials is being developed to interface with molecular and cellular features of immunity and ultimately shape or control anti-tumor responses. Recent advances that are supporting the advancement of engineered T cells are focused here. This class of cancer therapy has the potential to cure disease in subsets of patients, yet there remain challenges such as the need to improve response rates and safety while lowering costs to expand their use. To provide a focused overview, recent strategies in three areas of biomaterials research are highlighted: low-cost cell manufacturing to broaden patient access, noninvasive diagnostics for predictive monitoring of immune responses, and strategies for in vivo control that enhance anti-tumor immunity. These research efforts shed light on some of the challenges associated with T cell immunotherapy and how engineered biomaterials that interface with synthetic immunity are gaining traction to solve these challenges.


Subject(s)
Biocompatible Materials , Neoplasms , Humans , Immunologic Factors , Immunotherapy , Neoplasms/therapy , T-Lymphocytes
10.
Free Radic Biol Med ; 165: 368-384, 2021 03.
Article in English | MEDLINE | ID: mdl-33460768

ABSTRACT

Emerging evidences implicate the contribution of ROS to T cell activation and signaling. The tyrosine kinase, ζ-chain-associated protein of 70 kDa (ZAP70), is essential for T cell development and activation. However, it remains elusive whether a direct redox regulation affects ZAP70 activity upon TCR stimulation. Here, we show that deficiency of non-selenocysteine containing phospholipid hydroperoxide glutathione peroxidase (NPGPx), a redox sensor, results in T cell hyperproliferation and elevated cytokine productions. T cell-specific NPGPx-knockout mice reveal enhanced T-dependent humoral responses and are susceptible to experimental autoimmune encephalomyelitis (EAE). Through proteomic approaches, ZAP70 is identified as the key interacting protein of NPGPx through disulfide bonding. NPGPx is activated by ROS generated from TCR stimulation, and modulates ZAP70 activity through redox switching to reduce ZAP70 recruitment to TCR/CD3 complex in membrane lipid raft, therefore subduing TCR responses. These results reveal a delicate redox mechanism that NPGPx serves as a modulator to curb ZAP70 functions in maintaining T cell homeostasis.


Subject(s)
Proteomics , T-Lymphocytes , Animals , Homeostasis , Mice , Oxidation-Reduction , Receptors, Antigen, T-Cell/genetics , Receptors, Antigen, T-Cell/metabolism , Signal Transduction , T-Lymphocytes/metabolism
11.
J Control Release ; 330: 284-292, 2021 02 10.
Article in English | MEDLINE | ID: mdl-33221351

ABSTRACT

Pulmonary melioidosis is a bacterial disease with high morbidity and a mortality rate that can be as high as 40% in resource-poor regions of South Asia. This disease burden is linked to the pathogen's intrinsic antibiotic resistance and protected intracellular localization in alveolar macrophages. Current treatment regimens require several antibiotics with multi-month oral and intravenous administrations that are difficult to implement in under-resourced settings. Herein, we report that a macrophage-targeted polyciprofloxacin prodrug acts as a surprisingly effective pre-exposure prophylactic in highly lethal murine models of aerosolized human pulmonary melioidosis. A single dose of the polymeric prodrug maintained high lung drug levels and targeted an intracellular depot of ciprofloxacin to the alveolar macrophage compartment that was sustained over a period of 7 days above minimal inhibitory concentrations. This intracellular pharmacokinetic profile provided complete pre-exposure protection in a BSL-3 model with an aerosolized clinical isolate of Burkholderia pseudomallei from Thailand. This total protection was achieved despite the bacteria's relative resistance to ciprofloxacin and where an equivalent dose of pulmonary-administered ciprofloxacin was ineffective. For the first time, we demonstrate that targeting the intracellular macrophage compartment with extended antibiotic dosing can achieve pre-exposure prophylaxis in a model of pulmonary melioidosis. This fully synthetic and modular therapeutic platform could be an important therapeutic approach with new or re-purposed antibiotics for melioidosis prevention and treatment, especially as portable inhalation devices in high-risk, resource-poor settings.


Subject(s)
Melioidosis , Prodrugs , Animals , Humans , Lung , Macrophages, Alveolar , Melioidosis/drug therapy , Melioidosis/prevention & control , Mice , Polymers
12.
ACS Infect Dis ; 6(11): 2866-2871, 2020 11 13.
Article in English | MEDLINE | ID: mdl-33074651

ABSTRACT

Biofilms are one of the most challenging obstacles in bacterial infections. By providing protection against immune responses and antibiotic therapies, biofilms enable chronic colonization and the development of antibiotic resistance. As previous clinical observations and studies have shown, traditional antibiotic therapy alone cannot effectively treat and eliminate biofilm forming infections due to the protection conferred by the biofilm. A new strategy specifically targeting biofilms must be developed. Here, we specifically target and bind to the PAO1 biofilm and elucidate the molecular mechanism behind the interaction between a glycan targeted polymer and biofilm using a continuous flow biofilm model. The incubation of biofilms with fluorescent glycan targeted polymers demonstrated strong and persistent interactions with the mannose-containing polymer even after 24 h of continuous flow. To evaluate the role of major biofilm proteins LecB and CdrA, loss of function experiments with knockout variants established the dual involvement of both proteins in mannose targeted polymer retention. These results identify a persistent and specific targeting strategy to the biofilm, emphasizing its potential value as a delivery strategy and encouraging further exploration of biofilm targeted delivery.


Subject(s)
Mannose , Pseudomonas aeruginosa , Bacterial Proteins , Biofilms , Polymers
13.
EMBO Mol Med ; 12(1): e9386, 2020 01 09.
Article in English | MEDLINE | ID: mdl-31782617

ABSTRACT

Human caspase-4 and its mouse homolog caspase-11 are receptors for cytoplasmic lipopolysaccharide. Activation of the caspase-4/11-dependent NLRP3 inflammasome is required for innate defense and endotoxic shock, but how caspase-4/11 is modulated remains unclear. Here, we show that mice lacking the oxidative stress sensor glutathione peroxidase 8 (GPx8) are more susceptible to colitis and endotoxic shock, and exhibit reduced richness and diversity of the gut microbiome. C57BL/6 mice that underwent adoptive cell transfer of GPx8-deficient macrophages displayed a similar phenotype of enhanced colitis, indicating a critical role of GPx8 in macrophages. GPx8 binds covalently to caspase-4/11 via disulfide bonding between cysteine 79 of GPx8 and cysteine 118 of caspase-4 and thus restrains caspase-4/11 activation, while GPx8 deficiency leads to caspase-4/11-induced inflammation during colitis and septic shock. Inhibition of caspase-4/11 activation with small molecules reduces the severity of colitis in GPx8-deficient mice. Notably, colonic tissues from patients with ulcerative colitis display low levels of Gpx8 and high caspase-4 expression. In conclusion, these results suggest that GPx8 protects against colitis by negatively regulating caspase-4/11 activity.


Subject(s)
Caspases/metabolism , Colitis , Peroxidases/metabolism , Animals , Colitis/chemically induced , Colitis/metabolism , Colitis, Ulcerative/metabolism , Escherichia coli , Glutathione Peroxidase , Humans , Mice , Mice, Inbred C57BL , Mice, Knockout
14.
Cell Rep ; 29(8): 2134-2143.e7, 2019 Nov 19.
Article in English | MEDLINE | ID: mdl-31747588

ABSTRACT

Amyotrophic lateral sclerosis (ALS), the most common motor neuron disease, usually occurs in middle-aged people. However, the molecular basis of age-related cumulative stress in ALS pathogenesis remains elusive. Here, we found that mice deficient in NPGPx (GPx7), an oxidative stress sensor, develop ALS-like phenotypes, including paralysis, muscle denervation, and motor neurons loss. Unlike normal spinal motor neurons that exhibit elevated O-GlcNAcylation against age-dependent oxidative stress, NPGPx-deficient spinal motor neurons fail to boost O-GlcNAcylation and exacerbate ROS accumulation, leading to cell death. Mechanistically, stress-activated NPGPx inhibits O-GlcNAcase (OGA) through disulfide bonding to fine-tune global O-GlcNAcylation. Pharmacological inhibition of OGA rescues spinal motor neuron loss in aged NPGPx-deficient mice. Furthermore, expression of NPGPx in ALS patients is significantly lower than in unaffected adults. These results suggest that NPGPx modulates O-GlcNAcylation by inhibiting OGA to cope with age-dependent oxidative stress and protect motor neurons from degeneration, providing a potential therapeutic axis for ALS.


Subject(s)
Motor Neurons/metabolism , Oxidative Stress/physiology , beta-N-Acetylhexosaminidases/metabolism , Aging/physiology , Amyotrophic Lateral Sclerosis/metabolism , Animals , Female , Humans , Mice , Mice, Mutant Strains , Muscle Denervation , Oxidative Stress/genetics , Paralysis/metabolism
15.
Head Neck ; 41(9): 3241-3246, 2019 09.
Article in English | MEDLINE | ID: mdl-31173434

ABSTRACT

BACKGROUND: Postoperative hematoma is one of the most common complications of free flap reconstruction and compromises the perfusion of pedicles and perforators. Therefore, we reviewed our patients to analyze the associated risk factors. METHOD: This study involved a retrospective chart review from 2014 to 2016. We identified the patients undergoing free flap reconstructions for head and neck cancer. Patients with postoperative hematoma requiring surgical intervention were included. RESULT: We enlisted 289 patients undergoing head and neck reconstructions. Eighteen patients (6.2%) had postoperative hematomas of which 12 hematomas occurred within the first 3 days and 9 in the first 24 hours. Elevated systolic blood pressure increased the risk of hematoma formation, but hematoma was not associated with higher failure rate. Tachycardia was observed in the patients with hematoma. CONCLUSIONS: Transient elevated blood pressure increased the risk of hematoma. We suggest controlling systolic blood pressure below 150 mm Hg for prevention of hematoma.


Subject(s)
Blood Pressure/physiology , Head and Neck Neoplasms/physiopathology , Head and Neck Neoplasms/surgery , Hematoma/etiology , Plastic Surgery Procedures/adverse effects , Postoperative Complications/etiology , Adult , Aged , Female , Free Tissue Flaps , Head and Neck Neoplasms/complications , Hematoma/physiopathology , Humans , Male , Middle Aged , Postoperative Complications/physiopathology , Retrospective Studies , Sensitivity and Specificity , Time Factors
16.
Biomaterials ; 195: 38-50, 2019 03.
Article in English | MEDLINE | ID: mdl-30610992

ABSTRACT

Alveolar macrophages resident in the lung are prominent phagocytic effector cells of the pulmonary innate immune response, and paradoxically, are attractive harbors for pathogens. Consequently, facultative intracellular bacteria, such as Francisella tularensis, can cause severe systemic disease and sepsis, with high morbidity and mortality associated with pulmonary infection. Current clinical treatment, which involves exhaustive oral or intravenous antibiotic therapy, has limitations such as systemic toxicity and off-target effects. Pulmonary administration represents a promising alternative to systemic dosing for delivering antibiotics directly to the lung. Here, we present synthesized mannosylated ciprofloxacin polymeric prodrugs for efficient pulmonary delivery, targeting, and subsequent internalization by alveolar macrophages. We demonstrate significant improvement in efficacy against intracellular infections in an otherwise uniformly lethal airborne Francisella murine model (F. novicida). When administered to the lungs of mice in a prophylactic regimen, the mannosylated ciprofloxacin polymeric prodrugs led to 50% survival. In a treatment regimen that was concurrent with infection, the survival of mice increased to 87.5%. Free ciprofloxacin antibiotic was ineffective in both cases. This significant difference in antibacterial efficacy demonstrates the impact of this delivery platform based on improved physiochemical, pharmacokinetic, and pharmacodynamic properties of ciprofloxacin administered via our glycan polymeric prodrug. This modular platform provides a route for overcoming the limitations of free drug and increasing efficacy in treatment of intracellular infection.


Subject(s)
Macrophages, Alveolar/metabolism , Polysaccharides/chemistry , Prodrugs/chemistry , Francisella tularensis/metabolism , Magnetic Resonance Spectroscopy , Mannose/metabolism , Microbial Sensitivity Tests
17.
Nat Prod Res ; 33(18): 2655-2661, 2019 Sep.
Article in English | MEDLINE | ID: mdl-29737867

ABSTRACT

Three new glycosides (1-3), together with six known ones (4-9), were isolated from the root bark of Lycium chinense. Their structures were elucidated on the basis of MS and NMR spectroscopic data. Five compounds (3, 5, 6, 8, and 9) exhibited potent antihyperlipidemic activities in HepG2 cells as assessed by Oil Red O staining and significant inhibition of intracellular triglyceride (TG) levels, whereas two compounds (5 and 9) significantly reduced total cholesterol (TC) levels.


Subject(s)
Glycosides/chemistry , Glycosides/pharmacology , Hypolipidemic Agents/pharmacology , Lycium/chemistry , Cholesterol/metabolism , Drug Evaluation, Preclinical/methods , Hep G2 Cells , Humans , Hypolipidemic Agents/chemistry , Magnetic Resonance Spectroscopy , Molecular Structure , Plant Bark/chemistry , Plant Extracts/chemistry , Spectrometry, Mass, Electrospray Ionization , Triglycerides/metabolism
18.
J Control Release ; 287: 1-11, 2018 10 10.
Article in English | MEDLINE | ID: mdl-30099019

ABSTRACT

Intracellular bacterial infections localized to the lung alveolar macrophage (AM) remain one of the most challenging settings for antimicrobial therapy. Current systemic antibiotic treatment fails to deliver sustained doses to intracellular bacterial reservoirs, which necessitates prolonged treatment regimens. Herein, we demonstrate a new intracellular enzyme-cleavable polymeric prodrug with tailored ciprofloxacin release profiles in the lungs and AM. The targeted polymeric prodrug, termed "drugamers", incorporates (1) hydrophilic mannose residues to solubilize the antibiotic cargo and to target and enhance AM uptake and intracellular delivery, and (2) enzyme-cleavable linkage chemistry to provide high and sustained intracellular AM drug dosing. Prodrug monomers, derived from the antibiotic ciprofloxacin, were synthesized with either an intracellular protease cleavable dipeptide linker or a hydrolytic phenyl ester linker. RAFT polymerization was used to copolymerize the prodrug monomers and mannose monomer to synthesize well-defined drugamers without requiring a post-polymerization conjugation step. In addition to favorable in vivo safety profiles following intratracheal administration, a single dose of the drugamers sustained ciprofloxacin dosing in lungs and AMs above the minimum inhibitory concentration (MIC) over at least a 48 h period. The enzyme-cleavable therapeutic achieved a >10-fold increase in sustained ciprofloxacin in AM, and maintained a significantly higher whole lung PK as well. Ciprofloxacin dosed in identical fashion displayed rapid clearance with a half-life of approximately 30 min. Notably, inhalation of the mannose-targeted ciprofloxacin drugamers achieved full survival (100%) in a highly lethal mouse model of pneumonic tularemia, contrasted with 0% survival using free ciprofloxacin. These findings demonstrate the versatility of the drugamer platform for engineering the intracellular pharmacokinetic profiles and its strong therapeutic activity in treating pulmonary intracellular infections.


Subject(s)
Anti-Bacterial Agents/administration & dosage , Ciprofloxacin/administration & dosage , Delayed-Action Preparations/chemistry , Francisella/drug effects , Gram-Negative Bacterial Infections/drug therapy , Lung Diseases/drug therapy , Administration, Inhalation , Animals , Anti-Bacterial Agents/pharmacokinetics , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/therapeutic use , Ciprofloxacin/pharmacokinetics , Ciprofloxacin/pharmacology , Ciprofloxacin/therapeutic use , Drug Delivery Systems , Female , Lung/drug effects , Lung/metabolism , Lung Diseases/metabolism , Macrophages, Alveolar/drug effects , Macrophages, Alveolar/metabolism , Mannose/analogs & derivatives , Mice , Mice, Inbred C57BL , Microbial Sensitivity Tests , Polymers/chemistry , RAW 264.7 Cells , Tularemia/drug therapy
19.
Biomater Sci ; 6(7): 1976-1985, 2018 Jun 25.
Article in English | MEDLINE | ID: mdl-29850694

ABSTRACT

Pulmonary intracellular infections, such as tuberculosis, anthrax, and tularemia, have remained a significant challenge to conventional antibiotic therapy. Ineffective antibiotic treatment of these infections can lead not only to undesired side effects, but also to the emergence of antibiotic resistance. Aminoglycosides (e.g., streptomycin) have long been part of the therapeutic regiment for many pulmonary intracellular infections. Their bioavailability for intracellular bacterial pools, however, is limited by poor membrane permeability and rapid elimination. To address this challenge, polymer-augmented liposomes (PALs) were developed to provide improved cytosolic delivery of streptomycin to alveolar macrophages, an important host cell for intracellular pathogens. A multifunctional diblock copolymer was engineered to functionalize PALs with carbohydrate-mediated targeting, pH-responsive drug release, and endosomal release activity with a single functional polymer that replaces the pegylated lipid component to simplify the liposome formulation. The pH-sensing functionality enabled PALs to provide enhanced release of streptomycin under endosomal pH conditions (70% release in 6 hours) with limited release at physiological pH 7.4 (16%). The membrane-destabilizing activity connected to endosomal release was characterized in a hemolysis assay and PALs displayed a sharp pH profile across the endosomal pH development target range. The direct connection of this membrane-destabilizing pH profile to model drug release was demonstrated in an established pyranine/p-xylene bispyridinium dibromide (DPX) fluorescence dequenching assay. PALs displayed similar sharp pH-responsive release, whereas PEGylated control liposomes did not, and similar profiles were then shown for streptomycin release. The mannose-targeting capability of the PALs was also demonstrated with 2.5 times higher internalization compared to non-targeted PEGylated liposomes. Finally, the streptomycin-loaded PALs were shown to have a significantly improved intracellular antibacterial activity in a Francisella-macrophage co-culture model, compared with free streptomycin or streptomycin delivered by control PEGylated liposomes (13× and 16×, respectively). This study suggests the potential of PALs as a useful platform to deliver antibiotics for the treatment of intracellular macrophage infections.


Subject(s)
Anti-Bacterial Agents/pharmacology , Drug Delivery Systems/methods , Francisella tularensis/drug effects , Liposomes/pharmacology , Streptomycin/pharmacology , Animals , Anti-Bacterial Agents/metabolism , Arylsulfonates/chemistry , Drug Compounding/methods , Drug Liberation , Endosomes/drug effects , Endosomes/metabolism , Endosomes/microbiology , Fluorescent Dyes/chemistry , Francisella tularensis/growth & development , Francisella tularensis/metabolism , Hydrogen-Ion Concentration , Kinetics , Liposomes/chemical synthesis , Liposomes/metabolism , Mannose/metabolism , Methacrylates/chemistry , Mice , Phosphatidylcholines/chemistry , Phosphatidylethanolamines/chemistry , Polyethylene Glycols/chemistry , Pyridinium Compounds/chemistry , RAW 264.7 Cells , Streptomycin/metabolism
20.
J Pharm Biomed Anal ; 148: 189-204, 2018 Jan 30.
Article in English | MEDLINE | ID: mdl-29040936

ABSTRACT

Dan-Deng-Tong-Nao capsule (DDTN) was a traditional Chinese medicine (TCM) formula, and has been widely used for the treatment of stroke clinically which caused by blood stasis. However, the bioactive substances and mechanism are unclear because of the complex compositions in DDTN. In this research, An ultra high-performance liquid chromatography (UHPLC) coupled with hybrid quadruple-orbitrap mass spectrometry (Q-Orbitrap MS) method was utilized to identify the chemical constituents of DDTN. In total, 102 compounds including diterpenes, lactones, flavonoids, and phenolic acids were identified by the accurate masses and fragmentation pathways, and 18 of them were unambiguously determined by comparison of reference standards. Besides, 12 representative compounds were simultaneously quantification analyzed and successfully applified for detecting in 9 batches of DDTN samples by UHPLC-Q-Orbitrap MS in parallel reaction monitoring (PRM) mode. The proposed approach was validated to be satisfied in terms of linearity (0.9954-0.9999), LOD (0.771ng/mL), LOQ (2.568ng/mL), intra-day precision ( <2.68%), inter-day precision ( <4.52%), repeatability ( <2.96%), stability ( <3.21%), and recovery (94.6-105.5%). The results indicate that the method of combining UHPLC with Q-Orbitrap MS is practical and efficient for the chemical clarification in DDTN, and has great potential for the integrating quality control of other traditional Chinese medicines.


Subject(s)
Capsules/chemistry , Drugs, Chinese Herbal/chemistry , Chromatography, High Pressure Liquid/methods , Diterpenes/chemistry , Flavonoids/chemistry , Hydroxybenzoates/chemistry , Lactones/chemistry , Medicine, Chinese Traditional/methods , Quality Control , Reference Standards , Reproducibility of Results , Spectrometry, Mass, Electrospray Ionization/methods , Tandem Mass Spectrometry/methods
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