Accuracy of WatchPAT for the Diagnosis of Obstructive Sleep Apnea in Patients with Chronic Obstructive Pulmonary Disease.

The co-existence of chronic obstructive pulmonary disease (COPD) and obstructive sleep apnea (OSA), termed the overlap syndrome (OVS), is associated with adverse outcomes that may be reversed with treatment. However, diagnosis is limited by the apparent need for in-laboratory polysomnography (PSG). WatchPAT is a portable diagnostic device that is validated for the diagnosis of OSA that might represent an attractive tool for the diagnosis of OVS.Subjects with established COPD were recruited from a general population. Subjects underwent PSG and simultaneous recording with WatchPAT. Pulmonary function testing and questionnaires were also performed.A total of 36 subjects were recruited and valid data was obtained on 33 (age 63 ± 7, BMI 28 ± 7, 61% male, FEV1 56 ± 20% predicted). There was no significant difference in the apnea-hypopnea index (AHI) between PSG and WatchPAT (19 ± 20 versus 20 ± 15 events/h; mean difference 2(-2, 5) events/h; p = 0.381). The AHI was not significantly different in rapid eye movement (REM) and non-rapid eye movement (NREM) determined by PSG versus REM and NREM determined by WatchPAT. WatchPAT slightly overestimated total and REM sleep time, and sleep efficiency. The sensitivity of WatchPAT at an AHI cut-off of ≥5, ≥15, and ≥30 events/h for corresponding PSG AHI cut-offs was 95.8, 92.3, and 88.9, respectively; specificity was 55, 65.0, and 95.8, respectively.WatchPAT is able to determine OSA reliably in patients with COPD. The availability of this additional diagnostic modality may lead to improved detection of OVS, which may in turn lead to improved outcomes for a group of COPD patients at high risk of poor outcomes.

Antibody blockade of Dectin-2 suppresses house dust mite-induced Th2 cytokine production in dendritic cell- and monocyte-depleted peripheral blood mononuclear cell co-cultures from asthma patients.

BACKGROUND: Dectin-2, which is a C-type lectin, interacts with the house dust mite (HDM) Dermatophagoides pteronyssinus allergen. This study aimed to investigate whether Dectin-2 blockade by antagonistic monoclonal antibodies (MoAbs) attenuates HDM-induced allergic responses. METHODS: Two anti-Dectin-2 MoAbs were generated and validated for specific binding to Dectin-2 Fc fusion protein (Dectin-2.Fc) and inhibition of Dectin-2.Fc/HDM interaction. Patients with asthma exhibiting high titers of anti-D. pteronyssinus IgE were enrolled. Peripheral blood mononuclear cells with depleted CD14+ monocytes were obtained from these patients and co-cultured with autologous monocyte-derived conventional dendritic cells in the presence of D. pteronyssinus or its group 2 allergens (Der p 2). Interleukin (IL)-5 and IL-13 levels in the culture supernatants were determined using ELISA in the presence or absence of anti-Dectin-2 MoAbs. RESULTS: Two MoAbs, 6A4G7 and 17A1D10, showed specific binding to recombinant Dectin-2.Fc and inhibited HDM binding to Dectin-2.Fc. Both anti-Dectin-2 MoAbs inhibited IL-5 and IL-13 production in co-cultures with Der p 2 stimulation in a dose-dependent manner. 6A4G7 and 17A1D10 (3 µg/mL) significantly inhibited Der p 2-induced (3 µg/mL) IL-5 production by 69.7 and 86.4% and IL-13 production by 84.0 and 81.4%, respectively. Moreover, this inhibitory effect of the two MoAbs remained significant in the presence of D. pteronyssinus. CONCLUSIONS: Anti-Dectin-2 MoAbs significantly inhibited HDM-induced allergic responses in vitro and therefore have the potential to become therapeutic agents in mite-induced allergic diseases.

C-Reactive Protein Levels and the Risk of Incident Cardiovascular and Cerebrovascular Events in Patients with Obstructive Sleep Apnea.

PURPOSE: Patients with obstructive sleep apnea (OSA) are at increased risk of cardiovascular and cerebrovascular disease (CVD) but it is unclear who are at greatest risk. We determined whether the inflammatory marker, C-reactive protein (CRP), could be a useful prognostic biomarker. METHODS: Adult patients referred for polysomnography (PSG) with OSA were studied. Serum CRP levels were measured using ELISA the morning after PSG. Validated CV events within 4 years of PSG were ascertained by linking to provincial research datasets. RESULTS: 155 patients with OSA (AHI ≥ 5/h) had CRP measured. Median age was 53 and median AHI was 21/h. 10 patients (7.1%) suffered at least one event, but rates varied substantially by CRP (0/35 patients in the lowest quartile, and 7/39 in the highest CRP quartile). In the unadjusted analysis, patients in the highest CRP quartile (≥ 2.38 mg/L) were significantly more likely to suffer an event (odds ratio = 9.72 (95% CI 2.43-38.84), p = 0.001). CRP continued to be a significant predictor after controlling for multiple confounders. OSA severity and desaturation were not significantly associated with prospective events. CONCLUSIONS: In this small preliminary study, OSA patients with an elevated CRP were significantly more likely to suffer a CVD event in the 4 years after PSG. Although these findings need to be confirmed in larger prospective cohorts, CRP may be useful in risk stratifying OSA patients to guide therapy or to identify patients that might be most appropriate for clinical trials of CVD prevention.

Affinity-Based Screen for Inhibitors of Bacterial Transglycosylase.

The rise of antibiotic resistance has created a mounting crisis across the globe and an unmet medical need for new antibiotics. As part of our efforts to develop new antibiotics to target the uncharted surface bacterial transglycosylase, we report an affinity-based ligand screen method using penicillin-binding proteins immobilized on beads to selectively isolate the binders from complex natural products. In combination with mass spectrometry and assays with moenomycin A and salicylanilide analogues (1-10) as reference inhibitors, we isolated four potent antibacterials confirmed to be benastatin derivatives (11-13) and albofungin (14). Compounds 11 and 14 were effective antibiotics against a broad-spectrum of Gram-positive and Gram-negative bacteria, including Acinetobacter baumannii, Clostridium difficile, Staphylococcus aureus, and drug-resistant strains with minimum inhibitory concentrations in the submicromolar to nanomolar range.

Undecaprenyl Phosphate Phosphatase Activity of Undecaprenol Kinase Regulates the Lipid Pool in Gram-Positive Bacteria.

Bacteria cell walls contain many repeating glycan structures, such as peptidoglycans, lipopolysaccharides, teichoic acids, and capsular polysaccharides. Their synthesis starts in the cytosol, and they are constructed from a glycan lipid carrier, undecaprenyl phosphate (C55P), which is essential for cell growth and survival. The lipid derivative undecaprenol (C55OH) is predominant in many Gram-positive bacteria but has not been detected in Gram-negative bacteria; its origin and role have thus remained unknown. Recently, a homologue of diacylglycerol kinase (DgkA) in Escherichia coli (E. coli) was demonstrated to be an undecaprenol kinase (UK) in the Gram-positive bacterium Streptococcus mutans (S. mutans). In this study, we found that S. mutans UK was not only an undecaprenol kinase but also a Mg-ADP-dependent undecaprenyl phosphate phosphatase (UpP), catalyzing the hydrolysis of C55P to C55OH and a free inorganic phosphate. Furthermore, the naturally undetectable C55OH was observed in E. coli cells expressing S. mutans dgkA, supporting the phosphatase activity of UK/UpP in vivo. These two activities were indispensable to each other and utilized identical essential residues binding to their substrates, suggesting that both activities share the same active site and might involve a direct phosphoryl transfer mechanism. This study revealed a unique membrane enzyme displaying bifunctional activities determined by substrate binding and C55OH production. The reciprocal conversion of C55P and the undecaprenol pool efficiently regulate cell wall synthesis, especially in Gram-positive bacteria.

Carbohydrate-based vaccines with a glycolipid adjuvant for breast cancer.

Globo H (GH) is a hexasaccharide specifically overexpressed on a variety of cancer cells and therefore, a good candidate for cancer vaccine development. To identify the optimal carrier and adjuvant combination, we chemically synthesized and linked GH to a carrier protein, including keyhole limpet hemocyanion, diphtheria toxoid cross-reactive material (CRM) 197 (DT), tetanus toxoid, and BSA, and combined with an adjuvant, and it was administered to mice for the study of immune response. Glycan microarray analysis of the antiserum obtained indicated that the combination of GH-DT adjuvanted with the α-galactosylceramide C34 has the highest enhancement of anti-GH IgG. Compared with the phase III clinical trial vaccine, GH-keyhole limpet hemocyanion/QS21, the GH-DT/C34 vaccine elicited more IgG antibodies, which are more selective for GH and the GH-related epitopes, stage-specific embryonic antigen 3 (SSEA3) and SSEA4, all of which were specifically overexpressed on breast cancer cells and breast cancer stem cells with SSEA4 at the highest level (>90%). We, therefore, further developed SSEA4-DT/C34 as a vaccine candidate, and after immunization, it was found that the elicited antibodies are also IgG-dominant and very specific for SSEA4.

Immunogenicity study of Globo H analogues with modification at the reducing or nonreducing end of the tumor antigen.

Globo H-based therapeutic cancer vaccines have been tested in clinical trials for the treatment of late stage breast, ovarian, and prostate cancers. In this study, we explored Globo H analogue antigens with an attempt to enhance the antigenic properties in vaccine design. The Globo H analogues with modification at the reducing or nonreducing end were synthesized using chemoenzymatic methods, and these modified Globo H antigens were then conjugated with the carrier protein diphtheria toxoid cross-reactive material (CRM) 197 (DT), and combined with a glycolipid C34 as an adjuvant designed to induce a class switch to form the vaccine candidates. After Balb/c mice injection, the immune response was studied by a glycan array and the results showed that modification at the C-6 position of reducing end glucose of Globo H with the fluoro, azido, or phenyl group elicited IgG antibody response to specifically recognize Globo H (GH) and the GH-related epitopes, stage-specific embryonic antigen 3 (SSEA3) (also called Gb5) and stage-specific embryonic antigen 4 (SSEA4). However, only the modification of Globo H with the azido group at the C-6 position of the nonreducing end fucose could elicit a strong IgG immune response. Moreover, the antibodies induced by these vaccines were shown to recognize GH expressing tumor cells (MCF-7) and mediate the complement-dependent cell cytotoxicity against tumor cells. Our data suggest a new potential approach to cancer vaccine development.

Enzymatic synthesis of lipid II and analogues.

The emergence of antibiotic resistance has prompted active research in the development of antibiotics with new modes of action. Among all essential bacterial proteins, transglycosylase polymerizes lipid II into peptidoglycan and is one of the most favorable targets because of its vital role in peptidoglycan synthesis. Described in this study is a practical enzymatic method for the synthesis of lipid II, coupled with cofactor regeneration, to give the product in a 50-70% yield. This development depends on two key steps: the overexpression of MraY for the synthesis of lipid I and the use of undecaprenol kinase for the preparation of polyprenol phosphates. This method was further applied to the synthesis of lipid II analogues. It was found that MraY and undecaprenol kinase can accept a wide range of lipids containing various lengths and configurations. The activity of lipid II analogues for bacterial transglycolase was also evaluated.

Synthesis of a dendritic cell-targeted self-assembled polymeric nanoparticle for selective delivery of mRNA vaccines to elicit enhanced immune responses.

Recent development of SARS-CoV-2 spike mRNA vaccines to control the pandemic is a breakthrough in the field of vaccine development. mRNA vaccines are generally formulated with lipid nanoparticles (LNPs) which are composed of several lipids with specific ratios; however, they generally lack selective delivery. To develop a selective delivery method for mRNA vaccine formulation, we reported here the synthesis of polymeric nanoparticles (PNPs) composed of a guanidine copolymer containing zwitterionic groups and a dendritic cell (DC)-targeted aryl-trimannoside ligand for encapsulation and selective delivery of an mRNA to dendritic cells. A DC-targeted SARS-CoV-2 spike mRNA-PNP vaccine was shown to elicit a stronger protective immune response in mice compared to the traditional mRNA-LNP vaccine and those without the selective delivery design. It is anticipated that this technology is generally applicable to other mRNA vaccines for DC-targeted delivery with enhanced immune response.

New continuous fluorometric assay for bacterial transglycosylase using Förster resonance energy transfer.

The emergence of antibiotic resistance has prompted scientists to search for new antibiotics. Transglycosylase (TGase) is an attractive target for new antibiotic discovery due to its location on the outer membrane of bacteria and its essential role in peptidoglycan synthesis. Though there have been a few molecules identified as TGase inhibitors in the past thirty years, none of them have been developed into antibiotics for humans. The slow pace of development is perhaps due to the lack of continuous, quantitative, and high-throughput assay available for the enzyme. Herein, we report a new continuous fluorescent assay based on Förster resonance energy transfer, using lipid II analogues with a dimethylamino-azobenzenesulfonyl quencher in the lipid chain and a coumarin fluorophore in the peptide chain. During the process of transglycosylation, the quencher-appended polyprenol is released and the fluorescence of coumarin can be detected. Using this system, the substrate specificity and affinity of lipid II analogues bearing various numbers and configurations of isoprene units were investigated. Moreover, the inhibition constants of moenomycin and two previously identified small molecules were also determined. In addition, a high-throughput screening using the new assay was conducted to identify potent TGase inhibitors from a 120,000 compound library. This new continuous fluorescent assay not only provides an efficient and convenient way to study TGase activities, but also enables the high-throughput screening of potential TGase inhibitors for antibiotic discovery.

Synthesis and vaccine evaluation of the tumor-associated carbohydrate antigen RM2 from prostate cancer.

We have successfully developed a [1+2+3] one-pot strategy to synthesize the RM2 antigen hexasaccharide that was proposed to be a prostate tumor antigen. The structure of the synthetic product was verified by NMR analysis and antibody binding assay using a glycan microarray. In addition, the synthetic antigen was conjugated to a mutated diphtheria toxin (DT, CRM197) with different copy numbers and adjuvant combinations to form the vaccine candidates. After vaccination in mice, we used glycan microarrays to monitor their immune response, and the results indicated that, when one molecule of DT was incorporated with 4.7 molecules of RM2 on average (DT-RM4.7) and adjuvanted with the glycolipid C34, the combination exhibited the strongest anti-RM2 IgG titer. Moreover, the induced mouse antibodies mediated effective complement-dependent cytotoxicity (CDC) against the prostate cancer cell line LNCap.

Rapid preparation of mycobacterium N-glycolyl Lipid I and Lipid II derivatives: a biocatalytic approach.

Breaking down barriers: A rapid, inexpensive preparation of the structurally complex mycobacterial N-glycolyl Lipid I, Lipid II, and their analogues from a range of different synthetic N-glycolyl and N-glycinyl Park's nucleotides is described (see scheme). The biotransformations were catalyzed by a readily available biocatalyst obtained from a bacterial cell-free membrane fraction. The unnatural N-glycinyl Lipid II was found to be a substrate of Mycobacterium tuberculosis (Mtb) transglycosylase, PonA, and N-glycolyl Lipid I was a weak inhibitor against PonA.

High-throughput identification of compounds targeting influenza RNA-dependent RNA polymerase activity.

As influenza viruses have developed resistance towards current drugs, new inhibitors that prevent viral replication through different inhibitory mechanisms are useful. In this study, we developed a screening procedure to search for new antiinfluenza inhibitors from 1,200,000 compounds and identified previously reported as well as new antiinfluenza compounds. Several antiinfluenza compounds were inhibitory to the influenza RNA-dependent RNA polymerase (RdRP), including nucleozin and its analogs. The most potent nucleozin analog, 3061 (FA-2), inhibited the replication of the influenza A/WSN/33 (H1N1) virus in MDCK cells at submicromolar concentrations and protected the lethal H1N1 infection of mice. Influenza variants resistant to 3061 (FA-2) were isolated and shown to have the mutation on nucleoprotein (NP) that is distinct from the recently reported resistant mutation of Y289H [Kao R, et al. (2010) Nat Biotechnol 28:600]. Recombinant influenza carrying the Y52H NP is also resistant to 3061 (FA-2), and NP aggregation induced by 3061 (FA-2) was identified as the most likely cause for inhibition. In addition, we identified another antiinfluenza RdRP inhibitor 367 which targets PB1 protein but not NP. A mutant resistant to 367 has H456P mutation at the PB1 protein and both the recombinant influenza and the RdRP expressing the PB1 H456P mutation have elevated resistance to 367. Our high-throughput screening (HTS) campaign thus resulted in the identification of antiinfluenza compounds targeting RdRP activity.

Chemical probes for drug-resistance assessment by binding competition (RABC): oseltamivir susceptibility evaluation.

The wizard of OS (resistance): the binding difference of neuraminidase inhibitors (zanamivir versus oseltamivir (OS)) was used to establish an assay to identify the influenza subtypes that are resistant to OS but still sensitive to zanamivir. This assay used a zanamivir-biotin conjugate to determine the OS susceptibility of a wide range of influenza viruses and over 200 clinical isolates.

Dosimetric Comparison of Intensity-Modulated Radiation Therapy (IMRT) and Intensity-Modulated Proton Therapy (IMPT) for a Novel Oral Tongue Avoidance Concept in Low-Risk Squamous Cell Carcinoma of the Oral Tongue.

Purpose: After adequate surgical resection, early-stage oral tongue cancer patients can harbor a low risk of local recurrence but remain at risk of regional recurrence. Oral tongue avoidance during adjuvant radiation therapy is an attractive potential treatment strategy to mitigate treatment toxicity. We sought to quantify the dosimetric advantages of this approach and hypothesized that intensity-modulated proton therapy (IMPT) may further reduce organs at risk doses compared with intensity-modulated radiation therapy (IMRT). Materials and Methods: Five patients with oral tongue cancer treated with postoperative radiation therapy from August 2020 to September 2021 were retrospectively reviewed. Novel clinical target volume contours, excluding the oral tongue, were generated while maintaining coverage of bilateral at-risk lymph nodes. Comparison IMRT (X) and IMPT (PBT) plans were generated using standard treatment volumes (control) and avoidance volumes (study) (n = 4 plans/patient). Dosimetric variables for organs at risk were compared using the paired t test. Results: The prescribed dose was 60 Gy in 30 fractions. D95% clinical target volume coverage was similar between X and PBT plans for both control and study clinical target volumes. Comparing control with study plans, both X (58.9 Gy vs 38.3 Gy, P = .007) and PBT (60.2 Gy vs 26.1 Gy, P < .001) decreased the oral cavity dosemean. The pharyngeal constrictor dosemean was also reduced (P < .003). There was no difference between control and study plans for larynx (P = .19), parotid (P = .11), or mandible dose (P = .59). For study plans, PBT significantly reduced oral cavity dosemean (38.3 Gy vs 26.1 Gy, P = .007) and parotid dosemean (23.3 Gy vs 19.3 Gy, P = .03) compared with X. For control plans, there was no difference in oral cavity dosemean using PBT compared with X, but PBT did improve the parotid dosemean (26.6 Gy vs 19.7 Gy, P = .02). Conclusion: This study quantifies the feasibility and dosimetric advantages of oral tongue avoidance while still treating the at-risk lymph nodes for oral tongue cancer. The dosimetric difference between PBT and X was most prominent with an oral tongue-avoidance strategy.

Harnessing natural-product-inspired combinatorial chemistry and computation-guided synthesis to develop N-glycan modulators as anticancer agents.

Modulation of N-glycosylation using human Golgi α-mannosidase II (α-hGMII) inhibitors is a potential anticancer approach, but the clinical utility of current α-hGMII inhibitors is limited by their co-inhibition of human lysosomal α-mannosidase (α-hLM), resulting in abnormal storage of oligomannoses. We describe the synthesis and screening of a small library of novel bicyclic iminosugar-based scaffolds, prepared via natural product-inspired combinatorial chemistry (NPICC), which resulted in the identification of a primary α-hGMII inhibitor with 13.5-fold selectivity over α-hLM. Derivatization of this primary inhibitor using computation-guided synthesis (CGS) yielded an advanced α-hGMII inhibitor with nanomolar potency and 106-fold selectivity over α-hLM. In vitro studies demonstrated its N-glycan modulation and inhibitory effect on hepatocellular carcinoma (HCC) cells. In vivo studies confirmed its encouraging anti-HCC activity, without evidence of oligomannose accumulation.

Differential receptor binding affinities of influenza hemagglutinins on glycan arrays.

A library of 27 sialosides, including seventeen 2,3-linked and ten 2,6-linked glycans, has been prepared to construct a glycan array and used to profile the binding specificity of different influenza hemagglutinins (HA) subtypes, especially from the 2009 swine-originated H1N1 and seasonal influenza viruses. It was found that the HAs from the 2009 H1N1 and the seasonal Brisbane strain share similar binding profiles yet different binding affinities toward various α2,6 sialosides. Analysis of the binding profiles of different HA subtypes indicate that a minimum set of 5 oligosaccharides can be used to differentiate influenza H1, H3, H5, H7, and H9 subtypes. In addition, the glycan array was used to profile the binding pattern of different influenza viruses. It was found that most binding patterns of viruses and HA proteins are similar and that glycosylation at Asn27 is essential for receptor binding.

Regioselective synthesis of di-C-glycosylflavones possessing anti-inflammation activities.

Three methods are utilized to synthesize a variety of 6,8-di-C-glycosylflavones bearing identical or distinct glycosyl moieties. Some C-glycosylation compounds are found to have better anti-inflammation activities than the parent flavones. Among them, 6,8-di-C-glucosylapigenin (known as vicenin-2) shows inhibition of TNF-alpha expression and NO production with IC(50) values of 6.8 and 5.2 muM, respectively.

Combinatorial approach toward synthesis of small molecule libraries as bacterial transglycosylase inhibitors.

The development of iminocyclitol-based small molecule libraries against a bacterial TGase is described. An iminocyclitol was conjugated with a pyrophosphate mimic using either a 1,3-dipolar cycloaddition or reductive amination reaction, which was then condensed with a variety of lipophilic carboxylic acids in an amide bond coupling to generate a desired molecular library. With assistance of microtiter plate-based combinatorial chemistry and in situ screening, a potential inhibitor, the first potent iminocyclitol-based inhibitor against bacterial TGases was efficiently developed.

What works in coping with HIV? A meta-analysis with implications for coping with serious illness.

Knowledge of effective ways of coping with HIV is critical to help individuals with HIV maintain the best possible psychological and physical well-being. The purpose of the present article is to determine, through meta-analysis, the strength of the evidence regarding 2 questions: (a) Which types of coping are related to psychological and physical well-being among people with HIV? and (b) Do contextual (pre?post introduction of highly active antiretroviral therapies [HAART]; time since diagnosis), measurement (HIV-related event vs. generic prompts for coping measurement), or individual (gender) variables affect the extent to which coping is related to physical and psychological well-being? The authors' analysis demonstrates that Direct Action and Positive Reappraisal were consistently associated with better outcomes in people coping with HIV across affective, health behavior, and physical health categories. In contrast, disengagement forms of coping, such as Behavioral Disengagement and Use of Alcohol or Drugs to Cope, were consistently associated with poorer outcomes. The findings also indicate that in some cases, coping effectiveness was dependent on contextual factors, including time since diagnosis and the advent of HAART.