Nitrate promotes the growth and the production of short-chain fatty acids and tryptophan from commensal anaerobe Veillonella dispar in the lactate-deficient environment by facilitating the catabolism of glutamate and aspartate.

Veillonella spp. are nitrate-reducing bacteria with anaerobic respiratory activity that reduce nitrate to nitrite. They are obligate anaerobic, Gram-negative cocci that ferment lactate as the main carbon source and produce short-chain fatty acids (SCFAs). Commensal Veillonella reside in the human body site where lactate level is, however, limited for Veillonella growth. In this study, nitrate was shown to promote the anaerobic growth of Veillonella in the lactate-deficient media. We aimed to investigate the underlying mechanisms and the metabolism involved in nitrate respiration. Nitrate (15 mM) was demonstrated to promote Veillonella dispar growth and viability in the tryptone-yeast extract medium containing 0.5 mM L-lactate. Metabolite and transcriptomic analyses revealed nitrate enabled V. dispar to actively utilize glutamate and aspartate from the medium and secrete tryptophan. Glutamate or aspartate was further supplemented to a medium to investigate individual catabolism during nitrate respiration. Notably, nitrate was demonstrated to elevate SCFA production in the glutamate-supplemented medium, and further increase tryptophan production in the aspartate-supplemented medium. We proposed that the increased consumption of glutamate provided reducing power for nitrate respiration and aspartate served as a substrate for fumarate formation. Both glutamate and aspartate were incorporated into the central metabolic pathways via reverse tricarboxylic acid cycle and were linked with the increased production of acetate, propionate, and tryptophan. This study provides further understanding of the promoted growth and metabolic mechanisms by commensal V. dispar utilizing nitrate and specific amino acids to adapt to the lactate-deficient environment.IMPORTANCENitrate is a pivotal ecological factor influencing microbial community and metabolism. Dietary nitrate provides health benefits including anti-diabetic and anti-hypertensive effects via microbial-derived metabolites such as nitrite. Unraveling the impacts of nitrate on the growth and metabolism of human commensal bacteria is imperative to comprehend the intricate roles of nitrate in regulating microbial metabolism, community, and human health. Veillonella are lactate-utilizing, nitrate-reducing bacteria that are frequently found in the human body site where lactate levels are low and nitrate is at millimolar levels. Here, we comprehensively described the metabolic strategies employed by V. dispar to thrive in the lactate-deficient environment using nitrate respiration and catabolism of specific amino acids. The elevated production of SCFAs and tryptophan from amino acids during nitrate respiration of V. dispar further suggested the potential roles of nitrate and Veillonella in the promotion of human health.

Study on the difference of gut microbiota in DLY and Diqing Tibetan pigs induce by high fiber diet.

In order to investigate the regularity of fecal microorganisms changes in Landrace × Large White × Duroc (DLY) and Diqing Tibetan pigs (TP) induced by dietary fiber, and further explore the buffering effect of different intestinal flora structures on dietary stress. DLY (n = 15) and TP (n = 15) were divided into two treatments. Then, diet with 20% neutral detergent fiber (NDF) was supplemented for 9 days. Our results showed that the feed conversion efficiency of TP was significantly higher (p < 0.05) than that of DLY. The fecal microorganisms shared by the two groups gradually increased with the feeding cycle. In addition, the dispersion of Shannon, Simpson, ACE and Chao of TP decreased. Also, we found that the fecal microorganisms of TP (R2 = 0.2089, p < 0.01) and DLY (R2 = 0.3982, p < 0.01) showed significant differences in different feeding cycles. With the prolongation of feeding cycle, the similarity of fecal microbial composition between DLY and TP increased. Our study strongly suggests that the complex environment and diet structure have shaped the unique gut microbiota of TP, which plays a vital role in the buffering effect of high-fiber diets.

[Clinical Features of 17 Patients With Primary Angiitis of the Central Nervous System Confirmed by Brain Biopsy].

Objective To analyze the clinical features of 17 patients with primary angiitis of the central nervous system (PACNS) and thus facilitate the early diagnosis and treatment,reduce the recurrence and mortality,and improve the prognoses of this disease. Methods We collected the data of patients with PACNS diagnosed by brain biopsy from January 2009 to June 2023 and analyzed their clinical presentations,laboratory and imaging manifestations,electrophysiological and pathological changes,and treatment regimens and prognosis. Results The 17 patients diagnosed with PACNS via brain biopsy included one child and 16 adults.The subtyping results showed that 10,2,3,2,1,and 1 patients had tumorous,spinal cord-involved,angiography-positive,rapidly progressive,hemorrhagic,and amyloid ß-related PACNS,respectively.Eleven (64.7%) of the patients were complicated with secondary epilepsy.All the patients exhibited abnormal manifestations in head MRI,with 94.1% showing lesions with uneven enhancement around the lesions or in the leptomeninges. Magnetic resonance angiography revealed large vessel abnormalities in 3 patients,and spinal cord involvement was observed in 2 patients.Histopathological typing revealed 7 (43.7%) patients with lymphocytic vasculitis and 5 (31.2%) patients with necrotizing vasculitis.Eleven patients were treated with glucocorticoids and cyclophosphamide,which resulted in partial lesion disappearance and symptom amelioration in 6 patients upon reevaluation with head MRI after 3 months of maintenance therapy.Two,1,and 3 patients experienced rapid disease progression,death,and recurrence within 1 year,respectively.Three patients showed insensitivity to hormonotherapy and residual disabilities.Two patients received rituximab after relapse and remained clinically stable during a follow-up period of 0.5-1 year. Conclusion Tumorous PACNS was more prone to epilepsy,mainly occurring in males.The most common histopathological type was necrotizing vasculitis,which responded to hormonotherapy and had favorable outcomes.Therefore,for the young patients with epilepsy and intracranial tumorous lesions,the possibility of PACNS should be considered.Spinal cord involvement in PACNS was often located in the thoracic and cervical cords,suggesting a poorer prognosis.Electromyography commonly revealed neural conduction abnormalities in the anterior horn or roots,providing clues for differential diagnosis.For suspected spinal cord involvement,comprehensive electromyography is recommended.Rapidly progressive PACNS often presented infratentorial lesions,such as lesions in the pons and medulla,with a higher mortality rate.Hemorrhagic PACNS was rare,and a multifocal hemorrhagic lesion with enhancement in the intracranial region,particularly in young patients,should raise suspicion.For the patients with recurrent or progressive disease,rituximab is a recommended therapeutic option.

[Tumor-Like Primary Central Nervous System Vasculitis With Spina Involvement:Report of One Case].

Primary central nervous system vasculitis (PACNS) is a vasculitic disorder affecting small to medium-sized blood vessels primarily in the central nervous system,involving the brain,spinal cord,and meninges.Tumor-like PNCAS,a rare subtype of PACNS,is often misdiagnosed as intracranial malignancy,and that with spinal cord involvement is even more uncommon.The lack of specific clinical symptoms and imaging manifestations poses a challenge to the diagnosis of PACNS.This report presents a case of tumor-like PACNS with spinal cord involvement based on the pathological evidence,aiming to enrich the knowledge about this condition.

[Fatal Familial Insomnia With Significant Correlations Between Involuntary Movements and Postural Changes:Report of One Case].

Fatal familial insomnia,an autosomal dominant prion disease,is rare.We reported the clinical symptoms,examination results,diagnosis,treatment,and prognosis of a patient who was diagnosed with fatal familial insomnia.Furthermore,we described the unique clinical manifestations that involuntary movements and laryngeal stridor were significantly correlated with postural changes,aiming to provide reference for the clinical diagnosis,treatment,and research of the disease in the future.

Electrochemically Enabled Intramolecular Amino- and Oxysulfonylation of Alkenes with Sodium Sulfinates to Access Sulfonylated Saturated Heterocycles.

A practical and efficient electrochemical intramolecular amino- or oxysulfonylation of internal alkenes equipped with pendant nitrogen or oxygen-centered nucleophiles with sodium sulfinate was developed. Under undivided electrolytic cell conditions, a variety of sulfonylated N-heterocycles and O-heterocycles, such as tetrahydrofurans, tetrahydropyrans, oxepanes, tetrahydropyrroles, piperidines, δ-valerolactones, etc., were efficiently prepared from easily accessible unsaturated alcohols, carboxylic acids, and N-tosyl amines without the need for additional metal or exogenous oxidant. The robust electrochemical transformation features excellent redox economy, high diastereoselectivity, and broad substrate specificity, which provide a general and practical access to sulfone-containing heterocycles and would facilitate the related synthetic and biological studies based on this electrosynthesis.

Dual Photo-/Electrochromic Pyromellitic Diimide-Based Coordination Polymer.

By the combination of N,N'-bis(carboxymethyl)-pyromellitic diimide (H2CMPMD, 1) and zinc ions, a novel PMD-based coordination polymer (CP), [Zn(CMPMD)(DMF)1.5]·0.5DMF (2) (DMF = N,N'-dimethylformamide), has been prepared and characterized. 1 and 2 exhibit completely different photochromic properties, which are mainly reflected in the photoresponsive rate (5 s for 1 vs 1 s for 2) and coloration contrast (from colorless to light green for 1 vs green for 2). This phenomenon should be attributed to the introduction of zinc ions and the consequent formation of the distinct interfacial contacts of electron donors (EDs) and electron acceptors (EAs) (dn-π = 3.404 and 3.448 Å for 1 vs dn-π = 3.343, 3.359, 3.398, and 3.495 Å for 2), suggesting a subtle modulating effect of metal ions on interfacial contacts, photoinduced intermolecular electron transfer (PIET) and photochromic behaviors. Interestingly, the photochromic performance of 2 can be enhanced after the removal of coordinated DMF, which might be ascribed to the decrease of the distance of EDs/EAs caused by lattice shrinkage, which further improves the efficiency of PIET. Meanwhile, 2 displays rapid electrochromic behavior with an obvious reversible color change from colorless to green, which can be used in an electrochromic device. This work develops a new type of EA for the construction of stimuli-responsive functional materials with excellent dual photo-/electrochromic properties.

Identification of distinct cytokine/chemokine profiles in dermatomyositis with anti-transcriptional intermediary factor 1-γ antibody.

OBJECTIVES: DM and clinically amyopathic DM (CADM) patients with positive expression of anti-transcription intermediary factor 1-γ (anti-TIF1-γ) antibody (Ab) are characterized by distinct clinicopathological features. We aimed to determine the role of cytokine/chemokine profiles in the classification of anti-TIF1-γ positive DM/CADM patients. METHODS: Serum levels of 24 cytokines/chemokines were measured in 27 anti-TIF1-γ positive DM/CADM patients by a Luminex 200 system. Principal components analysis and unsupervised hierarchical clustering were used to reduce variables and establish patient subgroups. Spearman's correlation coefficient was calculated between cytokine/chemokine levels and disease activity markers. RESULTS: Among anti-TIF1-γ positive DM/CADM patients, two distinct patient clusters were identified. The diagnosis of CADM was more common in cluster 1 than in cluster 2 (58.3% vs 6.7%, P = 0.008). Skin disease activity was higher in cluster 2 than in cluster 1 as measured by Cutaneous DM Disease Area and Severity Index-Activity [38.6 (10.4) vs 25.3 (10.0), P = 0.003]. Patients within cluster 2 exhibited significant muscle weakness (Medical Research Council scale ≤ 3, 33.3% vs 0.0%, P = 0.047), higher levels of anti-TIF1-γ Ab [92.4 (20.6) vs 66.9 (13.9), P = 0.001] and an increased malignancy rate (73.3% vs 25.0%, P = 0.021). Cluster 2 exhibited higher serum levels of CXCL10 [564.2 (258.8) vs 122.0 (97.8), P < 0.001], CCL2 [1136.6 (545.4) vs 441.6 (163.3), P < 0.001], galectin-9 [38879.6 (20009.3) vs 12612.4 (6640.0), P < 0.001], IL-18 [436.1 (188.9) vs 243.0 (114.5), P = 0.003], TNF-α [9.3 (3.8) vs 5.6 (2.4), P = 0.007] and TNFRI [1385.1 (338.2) vs 2605.6 (928.5), P < 0.001] than cluster 1. CONCLUSION: In anti-TIF1-γ positive DM/CADM, we identified a 'skin-predominant' cluster and a 'hyperinflammation' cluster based on the cytokine/chemokine profiles.Cytokine/chemokine profiles in anti-TIF1-γ positive DM/CADM can identify discrete clusters of patients with different disease patterns, organ involvements and clinical outcomes.

Plasma lncRNA LOC338963 and mRNA AP3B2 are upregulated in paraneoplastic Lambert-Eaton myasthenic syndrome.

INTRODUCTION/AIMS: Lambert-Eaton myasthenic syndrome (LEMS) is an autoimmune neuromuscular junction disorder. Long noncoding RNA (lncRNA) can regulate the expression of mRNA and is involved in the development of autoimmune diseases, but few genetic studies are available. In this study we aimed to explore the lncRNA and mRNA changes of LEMS. METHODS: Plasma lncRNA and mRNA expression profiles of three LEMS patients with small cell lung cancer (SCLC) and three matched healthy controls were analyzed by microarray. Differentially expressed lncRNAs and adjacent mRNAs were jointly analyzed, and candidates were verified by quantitative real-time polymerase chain reaction (qRT-PCR). The identified genes were subsequently evaluated in 9, 8, and 4 patients with paraneoplastic LEMS, nontumor LEMS, and SCLC, respectively. Gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses were performed to determine possible functions. RESULTS: A total of 320 lncRNA and 168 mRNAs were differentially expressed in the three LEMS with SCLC and compared with healthy controls. Among these, lncRNA LOC338963 and its neighboring mRNA AP3B2 were upregulated jointly, which was confirmed by qRT-PCR. qRT-PCR revealed significant upregulation of the two genes in patients with paraneoplastic LEMS compared with nontumor LEMS or SCLC. GO analysis of AP3B2 identified the enrichment terms anterograde synaptic vesicle transport and establishment of synaptic vesicle localization. KEEG analysis showed that AP3B2 was enriched in lysosomal pathways. DISCUSSION: LOC338963 and AP3B2 were upregulated in patients with paraneoplastic LEMS, suggesting their involvement in pathogenesis. These genes could be targets for exploring the pathomechanism of paraneoplastic LEMS.

Longitudinal relationship between sensory impairments and depressive symptoms in older adults: The mediating role of functional limitation.

BACKGROUND: The underlying mechanism between sensory impairments (SIs) and depressive symptoms among Chinese older adults is not well understood. This study aims to explore the mediating role of functional limitation on the longitudinal relationship between SIs and depressive symptoms among older adults in China. METHODS: A total of 4130 older adults who participated in the 3-year follow-up China Health and Retirement Longitudinal Study (CHARLS) were included in the analysis. The hierarchical multiple linear regression model and nonparametric bootstrapping method were employed to explore the relationship between SIs and depressive symptoms, and the mediating role of functional limitation in this link. RESULTS: The prevalence of self-reported hearing impairment (HI) only, vision impairment (VI) only, and dual sensory impairment (DSI) at baseline were 5.7%, 22.2%, and 58.6%, respectively. After adjusting for controlling variables, older adults with DSI had significantly higher levels of depressive symptoms compared with those without SIs at baseline (ß = .07, p = .005). The magnitude of mediation effect from DSI to depressive symptoms via functional limitation was a*b = 0.060 (BCa 95% confidence interval: 0.031-0.094). CONCLUSIONS: Functional limitation partially mediated the relationship between DSI and depressive symptoms among Chinese older adults. Interventions of DSI and functional limitation should be included in depressive symptoms prevention among older adults in China.

Sugarcane Nitrogen Concentration and Irrigation Level Prediction Based on UAV Multispectral Imagery.

Sugarcane is the main industrial crop for sugar production, and its growth status is closely related to fertilizer, water, and light input. Unmanned aerial vehicle (UAV)-based multispectral imagery is widely used for high-throughput phenotyping, since it can rapidly predict crop vigor at field scale. This study focused on the potential of drone multispectral images in predicting canopy nitrogen concentration (CNC) and irrigation levels for sugarcane. An experiment was carried out in a sugarcane field with three irrigation levels and five fertilizer levels. Multispectral images at an altitude of 40 m were acquired during the elongating stage. Partial least square (PLS), backpropagation neural network (BPNN), and extreme learning machine (ELM) were adopted to establish CNC prediction models based on various combinations of band reflectance and vegetation indices. The simple ratio pigment index (SRPI), normalized pigment chlorophyll index (NPCI), and normalized green-blue difference index (NGBDI) were selected as model inputs due to their higher grey relational degree with the CNC and lower correlation between one another. The PLS model based on the five-band reflectance and the three vegetation indices achieved the best accuracy (Rv = 0.79, RMSEv = 0.11). Support vector machine (SVM) and BPNN were then used to classify the irrigation levels based on five spectral features which had high correlations with irrigation levels. SVM reached a higher accuracy of 80.6%. The results of this study demonstrated that high resolution multispectral images could provide effective information for CNC prediction and water irrigation level recognition for sugarcane crop.

Quantum Dot Nanobead-Based Fluorescence-Linked Immunosorbent Assay for Detection of Glycinin in Soybeans and Soy Products.

Soybean glycinin, as a major soybean allergen, is difficult to accurately quantify due to its large molecular weight and complex structure. CdSe/ZnS quantum dot nanobead (QB) is a core/shell fluorescent nanomaterial with strong fluorescent signals and high sensitivity at 630 nm. An immunosorbent assay based on CdSe/ZnS quantum dot nanobeads (QBs-FLISA) was developed for the glycinin quantification in soybean and soybean products. Here, the purified glycinin was coated on the microporous plate to serve as the coating antigen, and CdSe/ZnS nanobead conjugated with anti-glycinin polyclonal antibodies was used as fluorescent detection probe. The target glycinin in the sample and the coated antigen on the plate competitively adsorbed the antibody labeled the CdSe/ZnS QBs probes. The limits of detection and quantitation for glycinin were 0.035 and 0.078 µg mL-1, respectively. The recoveries of the spiked samples ranged from 89.8% to 105.6%, with relative standard deviation less than 8.6%. However, compared with ELISA, the sensitivities of QBs-FLISA for the detection of glycinin were increased by 7 times, and the detection time was shortened by two-thirds. This QBs-FLISA method has been effectively applied to the detection of soybean seeds with different varieties and soy products with different processing techniques, which will provide a rapid screening method for soybean and soybean products with low allergens.

VOLN27B: A New Head-Tailed Halovirus Isolated from an Underground Salt Crystal and Infecting Halorubrum.

A novel halovirus, VOLN27B, was isolated from a drill core sample taken at a depth of approximately 430 m, from a layer formed during the Cretaceous period (Anhui, China). VOLN27B infects the halophilic archaeon Halorubrum sp. LN27 and has a head-tailed morphotype with a contractile tail, typical of myoviruses. The average head diameter is 64 ± 2.0 nm, and uncontracted tails are 15 ± 1.0 × 65 ± 2.0 nm. The latent period is about 10 h. The maturing time of VOLN27B in cells of Halorubrum sp. LN27 was nearly 8 h. The adsorption time of VOLN27B on cells of Halorubrum sp. LN27 was less than 1 min. Virus particles are unstable at pH values less than 5 or when the NaCl concentration is below 12% (w/v). VOLN27B and Halorubrum sp. LN27 were recovered from the same hypersaline environment and provide a new virus-host system in haloarchaea.

Double Phase Inversion of Pickering Emulsion Induced by Magnesium Hydroxide Nanosheets Adsorbed with Sodium Dodecyl Sulfate.

Surfactants are often used as a cooperation stabilizer with solid particles for increasing the efficiency of Pickering emulsion. Accordingly, the effects of interaction between surfactants and solid particles on stabilizing Pickering emulsions have been attracting great attention. In this study, magnesium hydroxide (MH) nanosheets adsorbed with different amounts of sodium dodecyl sulfate (SDS) surfactants were designed and used to stabilize paraffin-water emulsions. Using SDS-adsorbed MH nanosheets as a stabilizer, the phenomenon of double phase inversion was found for Pickering emulsion. Pickering emulsion was inverted initially from O/W to W/O at about 0.022 mmol/g of the adsorption amount of SDS on the MH nanosheets, and subsequently back to O/W at about 2.312 mmol/g. The first phase inversion was because of the increased hydrophobicity of modified MH nanosheets, where SDS molecules were monolayer-adsorbed on the MH nanosheets surface. The second phase inversion occurred due to the bilayer adsorption of SDS on MH nanosheets, which converted the modified MH nanosheets hydrophilic again. These results are of great importance to understanding the double phase inversion of Pickering emulsions with the addition of surfactants and finding prospective applications in fields such as reversible drilling fluids and oil extraction.

Multiple food-borne trematodiases with profound systemic involvement: a case report and literature review.

BACKGROUND: Food-borne trematodiases are an important group of neglected global diseases. Affected patients in regions with low prevalence usually experience delayed diagnosis, especially when presenting with atypical clinical symptoms. Here, we presented a rare case of a Chinese patient infected with three food-borne trematodiases. CASE PRESENTATION: A 42-year-old man presented with diarrhea, lower extremity edema, and symptoms of cardiac dysfunction. He had a history of intermittent consumption of raw freshwater fishes for 6-7 years. Upon evaluation, he had eosinophilia, anemia, intrahepatic bile duct dilatation and a growing space-occupying lesion in the left atrium. The patient underwent a cardiac surgery which revealed an endocardial hematoma due to mechanical injuries. Imaging investigations also revealed intracranial and pulmonary lesions. A total of three trematodiases were diagnosed based upon microscopic stool examination, from which eggs of Clonorchis sinensis, Heterophyidae and Echinostomatidae were identified. Deposition of Clonorchis sinensis eggs was also observed from ileocecal squash slides. The patient was successfully treated with three cycles of praziquantel. CONCLUSIONS: Food-borne trematodiases may present with systemic involvement. Patients with dietary history of high risk or atypical ingestions should be evaluated for parasitic infection, even in non-endemic areas.

A combination of bovine serum albumin with insulin-transferrin-sodium selenite and/or epidermal growth factor as alternatives to fetal bovine serum in culture medium improves bovine embryo quality and trophoblast invasion by induction of matrix metalloproteinases.

This study investigated the use of bovine serum albumin (BSA) plus insulin-transferrin-sodium selenite (ITS) and/or epidermal growth factor (EGF) as alternatives to fetal bovine serum (FBS) in embryo culture medium. The developmental ability and quality of bovine embryos were determined by assessing their cell number, lipid content, gene expression and cryotolerance, as well as the invasion ability of trophoblasts. The percentage of embryos that underwent cleavage and formed a blastocyst was higher (P<0.01) in medium containing ITS plus EGF and BSA than in medium containing FBS. Culture with ITS plus EGF and BSA also increased the hatching ability of blastocysts and the total cell number per blastocyst. Furthermore, the beneficial effects of BAS plus ITS and EGF on embryos were associated with a significantly reduced intracellular lipid content, which increased their cryotolerance. An invasion assay confirmed that culture with ITS plus EGF and BSA significantly improved the invasion ability of trophoblasts. Real-time quantitative polymerase chain reaction analysis showed that the mRNA levels of matrix metalloproteinase-2 (MMP2) and MMP9, acyl-CoA synthetase long-chain family member 3, acyl-coenzyme A dehydrogenase long-chain and hydroxymethylglutaryl-CoA reductase significantly increased upon culture with ITS plus EGF and BSA. Moreover, protein expression levels of matrix metalloproteinase-2 and -9 increased (P<0.01) in medium supplemented with ITS plus EGF and BSA compared with medium supplemented with FBS. Taken together, these data suggest that supplementation of medium with ITS plus EGF and BSA improves invitro bovine embryo production, cryotolerance and invasion ability of trophoblasts.

Morphology control of rutile TiO2 with tunable bandgap by preformed ß-FeOOH nanoparticles.

Rutile TiO2 are widely used for applications of coatings, cosmetics, photoelectric devices and so on. However, effective control of well-defined morphology, size and composition of rutile TiO2 nanoparticles from agglomeration has always been a challenge. A new synthesis strategy was proposed to prepare rutile TiO2 with controllable morphology varied from flower-like structures to single-separated nanorods. The ß-FeOOH nanoparticles were generated by the hydrolysis of FeCl3 solution and could prevent the aggregation of TiO2 nanocrystals at early stages of the reaction; thus, could control the morphology of rutile nanoparticles. The morphology of rutile TiO2 nanoparticles could be controllably regulated from flower-like structures to individually separated nanorods. Meanwhile, the preformed ß-FeOOH also played a role of dopant. Fe ions were substitutionally doped into the bulk lattice of TiO2 nanocrystals and reduced the bandgap, which extended the solar radiation absorption range of rutile TiO2. The prepared TiO2 may be suitable for novel UV-blue light shielding agents and many other applications in photoelectric devices, photocatalysis, and so on due to its small size, unprecedented discrete rod-like structure and unique UV-vis light permeability.

In Vitro Exposure to PC-1005 and Cervicovaginal Lavage Fluid from Women Vaginally Administered PC-1005 Inhibits HIV-1 and HSV-2 Infection in Human Cervical Mucosa.

Our recent phase 1 trial demonstrated that PC-1005 gel containing 50 µM MIV-150, 14 mM zinc acetate dihydrate, and carrageenan (CG) applied daily vaginally for 14 days is safe and well tolerated. Importantly, cervicovaginal lavage fluid samples (CVLs) collected 4 or 24 h after the last gel application inhibited HIV-1 and human papillomavirus (HPV) in cell-based assays in a dose-dependent manner (MIV-150 for HIV-1 and CG for HPV). Herein we aimed to determine the anti-HIV and anti-herpes simplex virus 2 (anti-HSV-2) activity of PC-1005 in human cervical explants after in vitro exposure to the gel and to CVLs from participants in the phase 1 trial. Single HIV-1BaL infection and HIV-1BaL-HSV-2 coinfection explant models were utilized. Coinfection with HSV-2 enhanced tissue HIV-1BaL infection. In vitro exposure to PC-1005 protected cervical mucosa against HIV-1BaL (up to a 1:300 dilution) in single-challenge and cochallenge models. CG gel (PC-525) provided some barrier effect against HIV-1BaL at the 1:100 dilution in a single-challenge model but not in the cochallenge model. Both PC-1005 and PC-525 at the 1:100 dilution inhibited HSV-2 infection, pointing to a CG-mediated protection. MIV-150 and CG in CVLs inhibited HIV (single-challenge or cochallenge models) and HSV-2 infections in explants in a dose-dependent manner (P < 0.05). Stronger inhibition of HIV-1 infection by CVLs collected 4 h after the last gel administration was observed compared to infection detected in the presence of baseline CVLs. The anti-HIV and anti-HSV-2 activity of PC-1005 gel in vitro and CVLs in human ectocervical explants supports the further development of PC-1005 gel as a broad-spectrum on-demand microbicide.

Determination of nine volatile N-nitrosamines in tobacco and smokeless tobacco products by dispersive solid-phase extraction with gas chromatography and tandem mass spectrometry.

A method was developed for the determination of nine volatile N-nitrosamines in tobacco and smokeless tobacco products. The targets are N-nitrosodimethylamine, N-nitrosopyrrolidine, N-nitrosopiperidine, N-nitrosomorpholine, N-nitrosoethylmethylamine, N-nitrosodiethylamine, N-nitrosodipropylamine, N-nitrosobuylmethylmine, and N-nitrosodibutylamine. The samples were treated by dispersive solid-phase extraction using 1 g of primary secondary amine and 0.5 g of carbon and then analyzed by gas chromatography with tandem mass spectrometry with an electron impact ion source. The recoveries for the targets ranged from 84 to 118%, with <16% relative standard deviations at three spiking levels of 0.5, 1.25, and 2.5 ng/g. The limits of detection ranged from 0.03 to 0.15 ng/g. With the use of the proposed method, we detected the presence of six nitrosamines in the range of 0.4-30.7 ng/g. The study demonstrated that the method could be used as a rapid, convenient, and high-throughput method for N-nitrosamines analysis in tobacco matrix.