PC Concentration Research Articles

Leveraging ML for profiling lipidomic alterations in breast cancer tissues: a methodological perspective

In this study, a comprehensive methodology combining machine learning and statistical analysis was employed to investigate alterations in the metabolite profiles, including lipids, of breast cancer tissues and their subtypes. By integrating biological and machine learning feature selection techniques, along with univariate and multivariate analyses, a notable lipid signature was identified in breast cancer tissues. The results revealed elevated levels of saturated and monounsaturated phospholipids in breast cancer tissues, consistent with external validation findings. Additionally, lipidomics analysis in both the original and validation datasets indicated lower levels of most triacylglycerols compared to non-cancerous tissues, suggesting potential alterations in lipid storage and metabolism within cancer cells. Analysis of cancer subtypes revealed that levels of PC 30:0 were relatively reduced in HER2(−) samples that were ER(+) and PR(+) compared to those that were ER(−) and PR(−). Conversely, HER2(+) tumors, which were ER(−) and PR(−), exhibited increased concentrations of PC 30:0. This increase could potentially be linked to the role of Stearoyl-CoA-Desaturase 1 in breast cancer. Comprehensive metabolomic analyses of breast cancer can offer crucial insights into cancer development, aiding in early detection and treatment evaluation of this devastating disease.

The Effect of Renaltec on Serum Uremic Toxins in Cats with Experimentally Induced Chronic Kidney Disease.

Serum uremic toxins markedly increase in cats with chronic kidney disease (CKD) and have deleterious consequences. Renaltec is an oral adsorbent that binds uremic toxin precursors in the gut. In this prospective cohort study utilizing 13 purpose-bred cats with remnant kidney model-induced CKD (12 IRIS Stage 2, 1 IRIS Stage 3) eating a standardized renal diet, we aimed to assess the effect of Renaltec administration on serum indoxyl sulfate (IDS) and p-cresol sulfate (pCS) concentrations. Cats were sequentially treated with standard of care for 56 days, 500 mg Renaltec orally once daily for 56 days, and then three months later, 500 mg Renaltec orally twice daily for 56 days. Serum IDS and pCS concentrations were measured 28 and 56 days after the administration of Renaltec. Blood pressure and kidney function were measured before and 56 days after the administration of Renaltec. Significant decreases in serum IDS and pCS concentrations were observed for both once- and twice-daily dosing, particularly during the first 28 days of administration. More cats with BID dosing had clinically significant reductions in serum IDS and pCS concentrations than with SID dosing. Renaltec can reduce the serum concentrations of deleterious gut-derived uremic toxins in cats with CKD.

Liquid Chromatography-Mass Spectrometry Analytical Methods for the Quantitation of p-Cresol Sulfate and Indoxyl Sulfate in Human Matrices: Biological Applications and Diagnostic Potentials.

Indoxyl sulfate (IxS) and p-cresyl sulfate (pCS) are toxic uremic compounds with documented pathological outcomes. This review critically and comprehensively analyzes the available liquid chromatography-mass spectrometry methods quantifying IxS and pCS in human matrices and the biological applications of these validated assays. Embase, Medline, PubMed, Scopus, and Web of Science were searched until December 2023 to identify assays with complete analytical and validation data (N = 23). Subsequently, citation analysis with PubMed and Scopus was utilized to identify the biological applications for these assays (N = 45). The extraction methods, mobile phase compositions, chromatography, and ionization methods were evaluated with respect to overall assay performance (e.g., sensitivity, separation, interference). Most of the assays focused on human serum/plasma, utilizing acetonitrile or methanol (with ammonium acetate/formate or formic/acetic acid), liquid-liquid extraction, reverse phase (e.g., C18) chromatography, and gradient elution for analyte separation. Mass spectrometry conditions were also consistent in the identified papers, with negative electrospray ionization, select multiple reaction monitoring transitions and deuterated internal standards being the most common approaches. The validated biological applications indicated IxS and/or pCS were correlated with renal disease progression and cardiovascular outcomes, with limited data on central nervous system disorders. Methods for reducing IxS and/or pCS concentrations were also identified (e.g., drugs, natural products, diet, dialysis, transplantation) where inconsistent findings have been reported. The clinical monitoring of IxS and pCS is gaining significant interest, and this review will serve as a useful compendium for scientists and clinicians.

Effect of Bleaching Agents on Composite Resins with and without Bis-GMA: An In Vitro Study.

The objective was to evaluate the change in color, hardness, and roughness produced by carbamide peroxide (CP) at two different concentrations on two resins. The 16% or 45% CP was applied to 66 resin discs with and without Bis-GMA. The color was measured with a spectrophotometer, and ΔEab and ΔE00 were calculated. Microhardness tester and SEM were used. In both composites, the a* and b* coordinates tended to be red and yellow, respectively, and were significant in the Bis-GMA group (p < 0.05). The ΔEab and ΔE00 were higher in the composite with Bis-GMA, regardless of the treatment received (p < 0.05). The microhardness was reduced in both composites regardless of the PC concentration compared to the control (p < 0.05). The 45% CP reduced the microhardness in the resin group with Bis-GMA compared to 16% CP (p < 0.001) but was not significant in the resin without Bis-GMA (p = 1). An increase in roughness was directly proportional to the concentration of CP, and it was more notable in the composite without Bis-GMA. The composite with Bis-GMA showed a greater tendency to darken than the one without Bis-GMA. The surface hardness of the composite was reduced in both composites and was not influenced by CP concentration in the composite without Bis-GMA. Bleaching is a common procedure nowadays. It is important to know how CP affects composites to establish a prognosis of the treatments in terms of color change, roughness, and hardness.

Biomarkers of oxidative stress and bioaccumulation of trace metals in waterbirds from different rice fields systems

AbstractWe compared trace metal concentrations (Pb, Zn, Cd, Cu) in feathers and biomarkers in muscle and liver tissue of waterbirds from organic and conventional irrigated rice farms in South Brazil. Cu and Pb concentrations were higher in waterbirds from conventional farms, whereas Cd and Zn levels were elevated in organic farms. Birds foraging in organic farms exhibited lower CAT and SOD activity and higher NPSH, LPO, and PC concentrations compared to those in conventional farms. Higher Cu and Pb concentrations were associated with elevated SOD and CAT activity, more prevalent in birds frequenting conventional farms. Conversely, birds with higher Cd and Zn concentrations showed increased NPSH, LPO, and PC levels and were more common in organic farms. Our study underscores complex differences in trace metal accumulation and oxidative stress biomarkers among waterbirds in organic and conventional rice crops.

Development and in vitro characterization of the proliposome gel of terbinafine hydrochloride

The study was conducted to prepare the Proliposome Gel of Terbinafine Hydrochloride to improve the drug loading and to sustain the drug release of terbinafine hydrochloride. Proliposome gel of terbinafine hydrochloride were prepared by modified coacervation phase separation method by varying the concentrations of PC to cholesterol. The prepared proliposome gel was evaluated for its pH, viscosity, drug loading, and In vitro drug release studies. The appearance, particle size and drug entrapment of each produced formulation was also evaluated. All proliposome gel formulation made were consistent, homogenous, and white creamy gel.

Profiling and evaluation of phenolic compounds in olive mill wastewater in Jordan

Abstract Phenolic compounds (PCs) are prevalent in olive mill wastewater (OMW), offering numerous health benefits but concurrently posing environmental challenges. This study aims to comprehensively characterize PCs in OMW, both qualitatively and quantitatively. An accurate, sensitive, and cost-effective method was successfully developed for extracting and quantifying seven PCs in OMW. The extraction procedure was optimized to achieve the maximum recovery using a liquid-liquid extraction method. Concentrations of the identified PCs were determined using a high-performance liquid chromatography-diode array detector (HPLC-DAD). The seven PCs peaks were successfully separated on an RP-C8 column within a 23-minute runtime using a gradient mobile phase. The method underwent thorough validation, producing satisfactory results. Subsequently, the developed method was applied to analyze OMW from four olive mills in Jordan, revealing PC concentrations ranging from 139 to 430 mg/L. Tyrosol and hydroxytyrosol were identified as the most abundant compounds. Additionally, gas chromatography-mass spectrometry (GC-MS) separated and identified forty PCs. The total phenolic content was quantified, reaching a value of 1839 mg/L. Moreover, the antioxidant activity was assessed, yielding a maximum value of 95.8%. These results underscore the substantial levels of PCs in OMW, highlighting the importance of economically utilizing this water.

Emicizumab-mediated hemostatic function assessed by thrombin generation assay in an in vitro model of factor VIII-depleted thrombophilia plasma.

Patients with hemophilia A (PwHA) may have concurrent deficiency of representative anticoagulant proteins, protein (P)C, PS, and antithrombin (AT), which reduces bleeding frequency. However, emicizumab-driven hemostasis in PwHA with such thrombophilic potential remains unclarified. This study investigated the influence of natural anticoagulants on emicizumab-driven coagulation in HA model plasma. Various concentrations of PS and AT were added to PS-deficient plasma and AT-deficient plasma in the presence of anti-FVIII antibody (FVIIIAb; 10BU/mL). PC-deficient plasma was mixed with normal plasma at various concentrations in the presence of FVIIIAb. Emicizumab (50µg/mL) was added to these thrombophilic HA model plasmas, prior to tissue factor/ellagic acid-triggered thrombin generation assays. Co-presence of emicizumab increased peak thrombin values (PeakTh) dependent on PS, AT, and PC concentrations. Maximum coagulation potentials in the PS-reduced HA model plasmas remained normal in the presence of emicizumab. PeakTh were close to normal in the presence of 50%AT irrespective of emicizumab, but were higher than normal in the presence of 25%AT. Addition of recombinant FVIIa (corresponding to an administered dose of 90μg/kg) enhanced coagulation potential to normal levels. Our findings provide novel information on hemostatic regulation in emicizumab-treated PwHA with a possible thrombophilic disposition.

An integrated mycotoxin-mitigating agent can effectively mitigate the combined toxicity of AFB1, DON and OTA on the production performance, liver and oviduct health in broiler breeder hens

This study was to evaluate the efficacy of an integrated mycotoxin-mitigating agent in reducing the adverse effects of co-occurring dietary aflatoxin B1 deoxynivalenol and ochratoxin A on broiler breeder hens. 360 30-week-old Hubbard Efficiency Plus broiler breeder hens were allocated into four groups and received a basal diet (BD; Control), BD added 0.15 mg/kg aflatoxin B1+1.5 mg/kg deoxynivalenol+0.12 mg/kg ochratoxin A (Toxins), BD plus Toxins with 0.1% TOXO-XL (Toxins + XL1), and BD plus Toxins with 0.2% TOXO-XL (Toxins + XL2), respectively, for 8 weeks, and then received the same BD for another 4 weeks. Compared with control, mycotoxins decreased total egg weigh, egg laying rate, settable eggs rate, hatch of total eggs rate, egg quality, but increased feed/egg ratio and mortality rate, and impaired the liver and oviduct health during weeks 1–8 and(or) 9–12. It also increased PC and MDA concentrations, TUNEL-positive cells and IL-1β and IL-6 expression, and decreased T-AOC, GPX and CAT activities in liver and/or oviduct. Notably, most of these negative changes were mitigated by both dosages of TOXO-XL. Generally, 0.2% TOXO-XL displayed better mitigation effects than 0.1% TOXO-XL. Conclusively, these findings revealed that TOXO-XL could mitigate the combined mycotoxins-induced toxicity on the performance, liver and oviduct health, through the regulation of redox, immunity, and apoptosis in broiler breeder hens.

Machine learning for cyanobacteria mapping on tropical urban reservoirs using PRISMA hyperspectral data

Urban reservoirs are important for drinking water services and urban living. However, potentially toxic cyanobacteria blooms are frequently present due to human pollution and might threaten the urban water supply. Conveniently, cyanobacteria can be monitored by remote sensing-based approaches based on the spectral features of C-Phycocyanin (PC). Furthermore, methods leveraging Machine Learning Algorithms (MLA) for PC estimation from hyperspectral data have highlighted the potential to estimate PC more accurately - even at low concentrations. Since relatively few methodologies for PC retrieval in tropical environments have been developed or validated, this research evaluated PRISMA hyperspectral data processed with three MLA (Random Forest, Extreme Gradient Boost, and Support Vector Machines) to estimate PC concentrations in the Billings reservoir, Brazil. The same MLA were used to generate PC models using Wordview-3 and Landsat-8/OLI simulated data to assess the potential gain of using hyperspectral over multispectral data. A PRISMA image was processed with three atmospheric correction methods and validated with co-located in-situ data, where the best atmospherically corrected product was used to generate synthetic Landsat-8/OLI and Worldview-3 images. The PC models were calibrated and validated through Monte Carlo simulation using field radiometric and biological data (Chlorophyll-a, PC, and phytoplankton taxonomy) collected in eight field campaigns (N = 115). The PRISMA and the synthetic multispectral images were used for a second round of models’ validation using co-located PC measurements (match-up window ± 4 h). The global PC Mixture Density Network was also applied to the PRISMA data, and the estimates were compared with the other MLA. The results showed that the standard PRISMA surface reflectance product provided the best atmospheric correction (MAE < 20% for the 500–700 nm bands), while ACOLITE and 6SV underperformed it from two to more than ten-fold. Cyanobacteria species were abundant in 96% of the taxonomical samples, even though relatively low PC concentrations were found (PC from 0 to 301.81 μg/L and median PC = 2.9 μg/L). The global Mixture Density Network sharply overestimated PC (MAE = 280% and Bias = 280%), potentially due to Billings reservoir’s low PC:Chlorophyll-a ratio relative to the original training dataset. PRISMA/Random Forest (MAE = 45%) achieved the lowest error for orbital PC estimate, while Extreme Gradient Boost outperformed the other MLA using Worldview-3 (MAE = 49%) and Landsat-8 (MAE = 74%) synthetic imagery. Therefore, the results suggest hyperspectral and multispectral orbital data aligned with MLA are feasible for monitoring PC, even for waters containing low PC concentrations and reduced PC:Chlorophyll-a ratios.

The Effect of Dietary Protein Concentration on the Fecal Microbiome and Serum Concentrations of Gut-Derived Uremic Toxins in Healthy Adult Cats.

The purpose of this study was to evaluate the effect of feeding healthy adult cats with foods containing variable protein concentrations on the fecal microbiome and serum concentrations of the gut-derived uremic toxins indoxyl sulfate, p-cresol sulfate (pCS), and trimethylamine-n-oxide. Twenty healthy young adult cats were randomized into two groups and fed either a low-protein diet (LPD; 7.4 g/100 kcal ME) or a high-protein diet (HPD; 11.0 g/100 kcal ME) for a 12-week period. Serum uremic toxin concentrations were measured via liquid chromatography tandem mass spectrometry, and the fecal microbiome was characterized using shallow sequence shotgun metagenomics. Cats that consumed the HPD had higher pCS concentrations at 8 weeks (p = 0.028) when compared to baseline. After 12 weeks, cats fed the HPD had higher fecal alpha diversity indices at both the taxonomic and functional levels and lower fecal Bifidobacterium relative abundance compared to those cats fed the LPD. In conclusion, a change in diet and dietary protein concentration shifted the fecal microbial community and microbial function. Feeding cats a high amount of protein increased serum concentrations of the uremic toxin pCS; however, the effect was short-lived.

Effects of Anemoside B4 on Plasma Metabolites in Cows with Clinical Mastitis.

Anemoside B4 has a good curative effect on cows with CM; however, its impact on their metabolic profiles is unclear. Based on similar somatic cell counts and clinical symptoms, nine healthy dairy cows and nine cows with CM were selected, respectively. Blood samples were collected from cows with mastitis on the day of diagnosis. Cows with mastitis were injected with anemoside B4 (0.05 mL/kg, once daily) for three consecutive days, and healthy cows were injected with the same volume of normal saline. Subsequently, blood samples were collected. The plasma metabolic profiles were analyzed using untargeted mass spectrometry, and the concentrations of interleukin (IL)-1β, IL-6, and tumor necrosis factor-α (TNF-α) in serum were evaluated via ELISA. The cows with CM showed increased concentrations of IL-1β, IL-6, and TNF-α (p < 0.05). After treatment with anemoside B4, the concentrations of IL-1β, IL-6, and TNF-α were significantly decreased (p < 0.01). Untargeted metabolomics analysis showed that choline, glycocholic acid, PC (18:0/18:1), 20-HETE, PGF3α, and oleic acid were upregulated in cows with CM. After treatment with anemoside B4, the concentrations of PC (16:0/16:0), PC (18:0/18:1), linoleic acid, eicosapentaenoic acid, phosphorylcholine, and glycerophosphocholine were downregulated, while the LysoPC (14:0), LysoPC (18:0), LysoPC (18:1), and cis-9-palmitoleic acid were upregulated. This study indicated that anemoside B4 alleviated the inflammatory response in cows with CM mainly by regulating lipid metabolism.

A Preliminary Study of Cobalt Solvent Extraction from Nickel Sulphate Solution using Organic Extractant-PC-88A

In present study, a solvent extraction experiment has been done to separate cobalt from the nickel sulfate solution by using 2-ethythexyl phosponic acid mono-2-ethylhexyl ester (PC-88A) as extractant. The experiment was carried out on a laboratory scale by using a separating funnel to extract cobalt from the nickel sulfate solution with PC88A. The mixed solution was shake in separating funnel for a specified period of time, and after the solvent extraction experiment was finished the organic phase PC88 was separated from the nickel sulfate solution by decantation. The nickel and cobalt content in the aqueous nickel sulfate solution were then analyzed using Atomic absorption spectrophotometry (AAS). In this experiment, the variable for experiments were covering solution pH from 2 to 6, shaking time from 30 minutes to 120 minutes, shaking speed from 20 revolutions per minute (rpm) to 80 rpm, and the volumeratio of aqueous to organic phase (A:O ratio) was from 1:1 to 1:4. The effects that experimental variables to the cobalt extraction were observed in this experiment. The result of experiment at room temperature, solution pH 5, shaking speed 60 rpm, shaking time 90 minutes, A:O ratio 1:4 and concentration of PC- 88A 40% show 97.21% of cobalt can be extracted by PC-88A from nickel sulfate solution, thererfore it was necessary to conduct two stage extraction process to extract 100% of the cobalt from the nickel sulfate solution.

Prediction of abnormal proliferation risk of Phaeocystis globosa based on correlation mining of PC concentration indicator and meteorological factors along Qinzhou Bay, Guangxi

Prediction of abnormal proliferation risk of Phaeocystis globosa based on correlation mining of PC concentration indicator and meteorological factors along Qinzhou Bay, Guangxi

Sources Causing Long-Term and Seasonal Changes in Combustion-Derived Particulate Matter in the Urban Air of Sapporo, Japan, from 1990 to 2002

Fifty-one samples were collected seasonally to estimate the amounts of total suspended particulate (TSP) in Sapporo, Japan, from 1990 to 2002. The atmospheric concentration of combustion-derived particulate (Pc) was calculated based on the NP method using 1-nitropyrene and pyrene. The atmospheric TSP and Pc concentration ranges were between 31–121 µg m−3 of air (Mean ± standard deviation (SD) = 58.2 ± 20.2 µg m−3) and 31–121 µg m−3 (Mean ± SD = 8.2 ± 6.0 µg m−3), respectively. First-order linear regression equations suggested that the Pc fraction decreased faster than TSP. The highest and lowest Pc concentrations were observed in winter and summer, respectively, whereas the highest and lowest TSP concentrations were observed in spring and winter, respectively. The largest and smallest Pc/TSP concentration ratios were observed in winter (0.324) and summer (0.075), respectively. The seasonal fractions of high-temperature combustion-derived particulate (Ph) in Pc ranged from 0.56 (winter) to 0.75 (summer), suggesting that the contribution of vehicle emissions to Pc was always larger than those of coal and biomass combustion. The sources of long-term and seasonal change in Pc were elucidated by analyzing organic source markers. Atmospheric concentrations of polycyclic aromatic hydrocarbons (PAHs), nitropolycyclic aromatic hydrocarbons (NPAHs) and hopanes showed long-term and seasonal changes similar to those of Pc, although biomarkers of biomass and coal combustion, such as levoglucosan, mannosan, and galactosan were not as strongly correlated. These results suggest that the change in the Pc concentration was mainly affected by vehicle emissions rather than by coal and biomass combustion or secondary pollutant formation. The decrease in the Pc over the study period was mainly a result of the Japanese particulate matter/NOx regulations on vehicle exhaust.

Different choline supplement metabolism in adults using deuterium labelling

BackgroundCholine deficiency leads to pathologies particularly of the liver, brain and lung. Adequate supply is important for preterm infants and patients with cystic fibrosis. We analysed the assimilation of four different enterally administered deuterium-labelled (D9-) choline supplements in adults.MethodsProspective randomised cross-over study (11/2020–1/2022) in six healthy men, receiving four single doses of 2.7 mg/kg D9-choline equivalent each in the form of D9-choline chloride, D9-phosphorylcholine, D9-alpha-glycerophosphocholine (D9-GPC) or D9-1-palmitoyl-2-oleoyl-glycero-3-phosphoryl-choline (D9-POPC), in randomised order 6 weeks apart. Plasma was obtained at baseline (t = − 0.1 h) and at 0.5 h to 7d after intake. Concentrations of D9-choline and its D9-labelled metabolites were analysed by tandem mass spectrometry. Results are shown as median and interquartile range.ResultsMaximum D9-choline and D9-betaine concentrations were reached latest after D9-POPC administration versus other components. D9-POPC and D9-phosphorylcholine resulted in lower D9-trimethylamine (D9-TMAO) formation. The AUCs (0-7d) of plasma D9-PC concentration showed highest values after administration of D9-POPC. D9-POPC appeared in plasma after fatty acid remodelling, predominantly as D9-1-palmitoyl-2-linoleyl-PC (D9-PLPC), confirming cleavage to 1-palmitoyl-lyso-D9-PC and re-acylation with linoleic acid as the most prominent alimentary unsaturated fatty acid.ConclusionThere was a delayed increase in plasma D9-choline and D9-betaine after D9-POPC administration, with no differences in AUC over time. D9-POPC resulted in a higher AUC of D9-PC and virtually absent D9-TMAO levels. D9-POPC is remodelled according to enterocytic fatty acid availability. D9-POPC seems best suited as choline supplement to increase plasma PC concentrations, with PC as a carrier of choline and targeted fatty acid supply as required by organs. This study was registered at Deutsches Register Klinischer Studien (DRKS) (German Register for Clinical Studies), DRKS00020498, 22.01.2020.Study registrationThis study was registered at Deutsches Register Klinischer Studien (DRKS) (German Register for Clinical Studies), DRKS00020498.

Effects of Polysaccharide Concentrations on the Formation and Physical Properties of Emulsion-Templated Oleogels.

An emulsion template method was an effective way to prepare oleogels. However, there were few reports on how hydroxypropyl methylcellulose-pectin (HPMC-PC) mixtures affected the physicochemical properties of the obtained oleogels. In this study, the oleogels were prepared by an emulsion template method. The influences of HPMC and PC concentrations on the formation and physical properties of the emulsions and oleogels were investigated, by analyzing particle size distribution, microstructure, rheological test, oil loss, and crystallinity. The results of particle sizes and microstructure showed that a high concentration of HPMC and PC exhibited a better emulsification performance. The rheological tests indicated that a high concentration of HPMC and PC contributed to an increase in the mechanical strength of emulsions and oleogels. Moreover, an increase in an HPMC and PC concentration was beneficial to reduce the oil loss of oleogels. However, the change of HPMC and PC concentrations had no significant effect on the X-ray diffraction pattern of oleogels. This study could provide a theoretical basis for the construction of polysaccharide-based oleogels.

ALMA imaging of the cold molecular and dusty disk in the type 2 active nucleus of the Circinus galaxy

Context. The central engines of many active galactic nuclei (AGNs) are thought to be surrounded by warm molecular and dusty material in an axisymmetric geometry, thus explaining part of the observational diversity of active nuclei. Aims. We aim to shed light on the physical properties and kinematics of the molecular material in the nucleus of one of the closest type 2 active galaxies. Methods. To this end, we obtained high angular resolution Atacama Large Millimeter/submillimeter Array (ALMA) observations of the nucleus of the Circinus galaxy. The observations map the emission at 350 GHz and 690 GHz with spatial resolutions of ∼3.8 pc and ∼2.2 pc, respectively. Results. The continuum emission traces cold (T ≲ 100 K) dust in a circumnuclear disk with spiral arms on scales of 25 pc, plus a marginally resolved nuclear emission peak. The latter is not extended in polar direction as claimed based on earlier ALMA observations. A significant amount (of the order of 40%) of the 350 GHz emission is not related to dust, but most likely free-free emission instead. We detect CO(3−2) and CO(6−5) as well as HCO+(4−3), HCN(4−3), and CS(4−3). The CO emission is extended, showing a spiral pattern, similar to the extended dust emission. Towards the nucleus, CO is excited to higher transitions and its emission is self-absorbed, leading to an apparent hole in the CO(3−2) but not the CO(6−5) emission. On the other hand, the high gas density tracers HCO+, HCN, and CS show a strong, yet unresolved (≲4 pc) concentration of the emission at the nucleus, pointing at a very small ‘torus’. The kinematics are dominated by rotation and point at a geometrically thin disk down to the resolution limit of our observations. In contrast to several other AGNs, no HCN enhancement is found towards the nucleus. Conclusions. The Circinus nucleus is therefore composed of at least two distinct components: (1) an optically thin, warm outflow of ionised gas containing clouds of dust which are responsible for the polar mid-infrared emission, but not seen at submillimetre wavelengths; and (2) a cold molecular and dusty disk, traced by submillimetre continuum and line emission. The latter is responsible for the bulk of the obscuration of the nucleus. These findings support the most recent radiative transfer calculations of the obscuring structures in AGNs, which find a similar two-component structure.

Development of quantum dot-phthalocyanine integrated G-quadruplex /double-stranded DNA biosensor

In the present study, the phthalocyanine (Pc) integrated mercaptopropionic acid capped quantum dot (mpa@QD) biosensor has been developed for the quantitative determination of G-quadruplex and double-stranded DNA. The working principle of the developed biosensor platform is based on the quenching of the emission signal of the mpa@QD in the presence of Pc (closed position) and the recovery of the fluorescence signal in the presence of DNA (open position). The parameters affecting biosensor performance, such as Pc type and concentration, were optimized. Since the developed biosensor aimed to determine G-quadruplex and double-stranded DNA in biological samples, the effect of common ions (such as Na+, Mg2+) and serum albumin found in many biological matrices on the biosensor performance were examined. The effect of common ions on biosensor signal was negligible, except Zn2+. The analytical properties of the biosensor, such as linear range, calibration sensitivity, relative standard deviation %, the limit of detection, and quantification, were determined. The limit of detection and quantification values were found 0.055 μM and 0.18 μM for AS1411, 0.061 μM and 0.20 μM for Tel21, 0.038 μM and 0.13 μM for Tel45 and 0.091 μM and 0.30 μM for ctDNA. Several different synthetic samples were prepared. The spiked synthetic samples such as mammalian cell medium were used to evaluate the analytical performance of Pc-mpa@QD. All synthetic samples were prepared with polyethylene glycol, which resembles biological samples' crowded environment.

Molecular and Supramolecular Approach to Highly Photocytotoxic Phthalocyanines with Dual Cell Uptake Pathways and Albumin-Enhanced Tumor Targeting.

Phototherapy for non-invasive cancer treatment has been extensively studied. An urgent challenge in phototherapy application is to fabricate appropriate targeted agents to achieve efficient therapeutic effect. Herein, a molecular and supramolecular approach for targeting phototherapy was reasonably designed and realized through the axial sulfonate modification of silicon(IV) phthalocyanines (Pcs), followed by supramolecular interaction with albumin. This approach can not only improve the photoactivities (e.g., fluorescence emission and reactive oxygen species production) of the Pcs but also enhance their tumor targeting. Most importantly, one of the deigned Pcs (4) can target HepG2 cells through dual cell pathways, leading to an extremely high phototoxicity with an EC50 (i.e., concentration of Pcs to kill 50% of cells under light irradiation) value of 2.0 nM. This finding presents a feasible strategy to realize efficient targeting phototherapy.