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Few studies investigate the impact of anterior-posterior excitation frequency on the time-domain vibrational response and injury risk of the lumbar spine in seated individuals. Firstly, this study utilised a previously developed finite element model of an upright seated human body on a rigid chair without a backrest to investigate the modes that affect the anterior-posterior vibrations of the seated body. Subsequently, transient dynamic analysis was employed to calculate the lumbar spine's time-domain responses (displacement, stress, and pressure) and risk factors under anteroposterior sinusoidal excitation at varying frequencies (1-8 Hz). Modal analysis suggested the frequencies significantly affecting the lumbar spine's vibration were notably at 4.7 Hz and 5.5 Hz. The transient analysis results and risk factor assessment indicated that the lumbar responses were most pronounced at 5 Hz. In addition, risk factor assessment showed that long-term exposure to 8 Hz vibration was associated with a greater risk of lumbar injury.
Although the anterior-posterior resonance frequency of the sitting body is around 1 Hz, the anterior-posterior vibrations approaching 5 Hz and at 8 Hz inflict more significant harm upon the lumbar spine than other frequencies, thereby elevating the risk of lumbar injury and back disorders.
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Octylphenol polyethoxylates (OPEOn) are composed of a hydrophobic octylphenol (OP) group and a hydrophilic polyethylene oxide (EO) chain and are widely used in commercial products. Shorter EO chains and OPEOn biometabolites have been identified as endocrine-disrupting contaminants and can threaten biotic factors in the ecosystem. In this study, OPEOn at three EO lengths (TX-45, TX-114, and TX-165) were selected in monomer (MN) or micelle (MC) state for batch experiments under aerobic conditions, with results showing biodegradation rates of 90 % within 35-70 h. The pseudo-first-order constant (k) of OPEOn biodegradation was observed in the order TX-45 (0.1414 h-1) > TX-114 (0.0556 h-1) > TX-165 (0.0485 h-1), with biomineralisation reaching at least 80 % for all OPEOn. The selective biodegradation of EO chains was also measured, with initial accumulation of OPEO3 observed along with the depletion of longer EO chains for TX-45 and TX-114 in both the MN and MC states. A similar trend was observed for the MN state of TX-165, with OPEO3-OPEO9 observed to accumulate and reduced after 70 h. MC biodegradation was accomplished via the initial accumulation of OPEO3-OPEO9. The amounts of OPEO3 increased and others reduced; however, OPEO3 remained high at the end of biodegradation for TX-165. Bacterial community analysis indicated that the genera Sphingobium spp., Pseudomonas spp., Flavobacterium spp., Comamonas spp., and Sphingopyxis spp. dominate OPEOn biodegradation, and they have their roles during biodegradation, and the community-level physiological profile (CLPP) was also changed by biodegradation in both the MN and MC states.
Subject(s)
Biodegradation, Environmental , Phenols , Phenols/metabolism , Polyethylene Glycols/metabolism , Bacteria/metabolism , Aerobiosis , Endocrine Disruptors/metabolismABSTRACT
Organismal aging involves functional declines in both somatic and reproductive tissues. Multiple strategies have been discovered to extend lifespan across species. However, how age-related molecular changes differ among various tissues and how those lifespan-extending strategies slow tissue aging in distinct manners remain unclear. Here we generated the transcriptomic Cell Atlas of Worm Aging (CAWA, http://mengwanglab.org/atlas ) of wild-type and long-lived strains. We discovered cell-specific, age-related molecular and functional signatures across all somatic and germ cell types. We developed transcriptomic aging clocks for different tissues and quantitatively determined how three different pro-longevity strategies slow tissue aging distinctively. Furthermore, through genome-wide profiling of alternative polyadenylation (APA) events in different tissues, we discovered cell-type-specific APA changes during aging and revealed how these changes are differentially affected by the pro-longevity strategies. Together, this study offers fundamental molecular insights into both somatic and reproductive aging and provides a valuable resource for in-depth understanding of the diversity of pro-longevity mechanisms.
Subject(s)
Aging , Caenorhabditis elegans , Longevity , Transcriptome , Longevity/genetics , Animals , Aging/genetics , Aging/physiology , Caenorhabditis elegans/genetics , Polyadenylation/genetics , Organ Specificity , Gene Expression Profiling , Germ Cells/metabolism , Germ Cells/cytologyABSTRACT
Bacteria, omnipresent in our environment and coexisting within our body, exert dual beneficial and pathogenic influences. These microorganisms engage in intricate interactions with the human body, impacting both human health and disease. Simultaneously, certain organelles within our cells share an evolutionary relationship with bacteria, particularly mitochondria, best known for their energy production role and their dynamic interaction with each other and other organelles. In recent years, communication between bacteria and mitochondria has emerged as a new mechanism for regulating the host's physiology and pathology. In this review, we delve into the dynamic communications between bacteria and host mitochondria, shedding light on their collaborative regulation of host immune response, metabolism, aging, and longevity. Additionally, we discuss bacterial interactions with other organelles, including chloroplasts, lysosomes, and the endoplasmic reticulum (ER).
Subject(s)
Bacteria , Host-Pathogen Interactions , Mitochondria , Animals , Humans , Bacteria/metabolism , Endoplasmic Reticulum/metabolism , Endoplasmic Reticulum/microbiology , Lysosomes/metabolism , Lysosomes/microbiology , Mitochondria/metabolism , Organelles/metabolismABSTRACT
Liangshan Prefecture is one of the three major forest areas in Sichuan Province and one of the three major disaster areas of forest fire. We measured the physicochemical properties and combustion performances of different organs (leaves and branches) of 15 main economic tree species in Liangshan, and analyzed the bioecology characteristics, silviculture characteristics and value characteristics of different tree species. We investigated the fire resistance of different tree species to screen out fire-resistant species suitable for economic forest development in Liangshan Prefecture, and improve the biological fire prevention ability. The seven physicochemical properties and combustion performances indices of 15 tree species showed significant differences. Except for crude ash and lignin, the weights of moisture content, caloric value, ignition point, crude fat, and crude fibre of leaves were higher than those of branches. Crude fibre index of leaves (9.6%) and the crude ash index of branches (9.9%) were the highest weight indices of the two organs, respectively. Based on the fire resistance, we divided all the species into three classes, i.e., class â (excellent fire-resistance trees) Juglans regia and Morus alba; class â ¡ (better fire-resistant trees) Sapium sebiferum, Mangifera indica, Phyllanthus emblica, Eriobotrya japonica, Ligustrum lucidum, Castanea mollissima, and Punica granatum; class â ¢ (poor fire-resistant trees) Pinus armandii, Illicium simonsii, Morella rubra, Sapindus mukorossi, Olea europaea and Camellia oleifera. J. regia and M. alba had fireproof solid performance and could be used as the preferred species for fireproof economic forest in Liangshan region. It was suggested that to use class â to â ¡ fire-resistant tree species built the main fireproof isolated forest belt, and pay attention to fire prevention after planting class â ¢ tree species in a large area.
Subject(s)
Fires , Wildfires , Trees , Forests , ChinaABSTRACT
OBJECTIVE: To investigate the influence of sacroiliac interosseous ligament tension and laxity on the biomechanics of the lumbar spine. METHODS: A static analysis of a three-dimensional finite element model of the Lumbar-Pelvic is conducted to verify the model's effectiveness. Adjusting the sacroiliac ligament's elasticity modulus under a 10Nm lumbar flexion/extension moment, it simulates ligament tension/laxity to calculate vertebrae displacements, intervertebral disc stress and deformation, nucleus pulposus pressure, facet joint force, and ligament stress. RESULTS: With the elastic modulus of the sacroiliac ligament changing by +50%, -50%, and -90%, the angular displacement of vertebra 3 in forward flexion changes by +1.64%, -4.84%, and -42.3%, and the line displacements change by +5.7%, -16.4%, and -144.9%, respectively; and the angular displacements in backward extension change by +0.2%, -0.6%, -5.9% and the line displacements change by +5.5%, -14.3%, and -125.8%. However, the angular displacement and center distance between adjacent vertebrae do not change, leading to no change in the maximum stress of the intervertebral disc and the maximum pressure in the nucleus pulposus. Flexion and extension directly affect the deformation and stress magnitude and distribution in the lumbar spine. CONCLUSIONS: While sacroiliac interosseous ligament laxity and tension have little effect on disc deformation and stress, and nucleus pulposus pressure, they reduce the stability of the lumbar-sacral vertebrae. In a forward flexion state, the lumbar ligaments bear a large load and are prone to laxity, thereby increasing the risk of lumbar injury.
Subject(s)
Finite Element Analysis , Ligaments, Articular , Lumbar Vertebrae , Sacroiliac Joint , Humans , Biomechanical Phenomena/physiology , Sacroiliac Joint/physiopathology , Ligaments, Articular/physiopathology , Ligaments, Articular/physiology , Range of Motion, Articular/physiology , Joint Instability/physiopathology , Elastic Modulus , Stress, MechanicalABSTRACT
The study aimed to investigate the dynamic characteristics of the cervical spine and determine the effect of the material properties of the cervical spinal components on it. A finite element model of the head-cervical spine was developed based on CT scan data, and the first six orders of modes (e.g. flexion-extension, lateral bending, and vertical, etc.) were verified by experimental and simulation studies. The material sensitivity study was conducted by varying elasticity modulus of cervical hard tissues (cortical bone, cancellous bone, endplates, and posterior elements) and soft tissues (intervertebral disc and ligaments). The results showed that increasing the elastic modulus of ligaments by 4 times increased the natural frequency by 77%, while increasing that of cancellous bone by 4 times only increased the natural frequency by 6%. In the axial mode, the cervical spine had not only axial deformation but also anterior-posterior deformation, with the largest deformation located at the intervertebral disc C6-C7. Decreasing the elastic modulus of a component in soft tissues by 80% increased modal displacement by up to 62%. The material properties of the intervertebral discs and ligaments had opposite effects on the modal displacement and deformation of the cervical spine. Low cervical discs were more susceptible to injury in a vertical vibration environment. Cervical spine dynamics were more sensitive to soft tissue material properties than to hard tissue material properties. Disc degeneration could reduce the range of vibratory motion of the cervical spine, thereby reducing the ability of the cervical spine to cushion head impacts.
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Objective:To investigate the application value of optical coherence tomography (OCT) and intravascular ultrasound (IVUS) in evaluating flow diverter (FD) apposition and endothelialization in aneurysm animal models, and analyze the effect of incomplete stent apposition (ISA) on aneurysm lumen healing and stent endothelialization.Methods:Lateral common carotid artery aneurysm models in swines were established by surgical method and then FD was implanted. Immediately after surgery, OCT and IVUS were used to evaluate the locations and degrees of ISA, and difference between these 2 methods in evaluating FD apposition was compared. DSA was performed at 12 weeks after surgery to evaluate the aneurysm occlusion (Kamran grading) and stent patency. OCT and IVUS were used again to observe the stent endothelial situation; by comparing with histopathologic results, effect of ISA on aneurysm healing and stent endothelialization was analyzed.Results:Lateral common carotid artery aneurysm models in 6 swines were established, and 6 Tubridge FDs were successfully implanted. Compared with IVUS (3 stents, 4 locus), OCT could detect more ISA (6 stents, 14 locus); and the vascular diameter change area (7 locus), aneurysm neck area (4 locus) and the head and tail of FD (3 locus) were the main sites of FD malapposition; average distance between stent wire and vessel wall was (560.14±101.48) μm. At 12 weeks after surgery, DSA showed that 1 patient had a little residual contrast agent at the aneurysm neck (Kamran grading 3), and the remaining 5 had complete aneurysm occlusion (Kamran grading 4). One FD had moderate lumen stenosis, and the other 5 FDs had lumen patency. OCT indicated mostly disappeared acute ISA; ISA proportion decreased to 21.4 % (3/14), including 2 in the aneurysm neck and 1 in the partial stent. Histopathological results showed bare stent woven silk, without obvious endothelial coverage; in one FD with luminal stenosis, intimal hyperplasia was mainly composed of vascular smooth muscle cells.Conclusion:In carotid artery aneurysm model with FD implantation, OCT can detect more ISA than IVUS; most acute ISA have good outcome at 12 th week of follow-up, while severe ISA can cause delayed FD endothelialization and delayed aneurysm occlusion.
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Aim To investigate the role of metabolites of eicosapentaenoic acid (EPA) in promoting the transdifferentiation of pancreatic α cells to β cells. Methods Male C57BL/6J mice were injected intraperitoneally with 60 mg/kg streptozocin (STZ) for five consecutive days to establish a type 1 diabetes (T1DM) mouse model. After two weeks, they were randomly divided into model groups and 97% EPA diet intervention group, 75% fish oil (50% EPA +25% DHA) diet intervention group, and random blood glucose was detected every week; after the model expired, the regeneration of pancreatic β cells in mouse pancreas was observed by immunofluorescence staining. The islets of mice (obtained by crossing GCG
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BACKGROUND:Sarcopenia refers to age-related progressive,systemic muscle mass reduction and/or muscle strength decline or muscle physiological function decline,which is related to the occurrence of a variety of adverse outcomes in older adults.Exercise is considered to be one of the main strategies for combating sarcopenia in older adults,but there is a lack of specific intervention methods of different exercise patterns to intervene in sarcopenia. OBJECTIVE:To elaborate the main influencing factors of sarcopenia and the research progress of different exercise methods to improve sarcopenia in older adults,providing reference and basis for combating sarcopenia in older adults. METHODS:Web of Science,PubMed,CNKI,VIP,WanFang databases were retrieved for relevant literature published from January 2000 to October 2023 using the keywords of"sarcopenia,sport,exercise intervention,resistant training,aerobic exercise,whole body vibration training,mixed training,physical performance,muscle strength,muscle mass"in Chinese and English,respectively.A total of 126 articles were included for review. RESULTS AND CONCLUSION:Resistance exercise is still the most effective way to prevent and treat senile sarcopenia,and the effect of high-intensity resistance exercise is more significant.However,in practical application,we should pay attention to the gradual increase of training load intensity.Aerobic exercise combined with resistance exercise is more effective to improve muscle mass and function in the elderly than a single exercise mode.It is suggested that older adults can carry out the transition of low-intensity aerobic exercise in the early stage and increase resistance exercise individually in the late stage.Whole body vibration training is a new treatment method for the prevention and treatment of senile sarcopenia,but particular attention should be paid to the effects of frequency,amplitude,and duration on patients during practical application.Multicomponent exercise combines different exercise modes,which can give full play to their respective advantages,so as to personalize exercise interventions.
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Objective:To investigate the application value of shear wave elastography (SWE) in the evaluation of T re-staging after neoadjuvant chemoradiotherapy (nCRT) for locally advanced rectal cancer.Methods:Clinical, endorectal ultrasound (ERUS) and SWE data of 271 patients with locally advanced rectal cancer who underwent nCRT and total mesorectal excision in Fujian Medical University Union Hospital from October 2021 to March 2023 were prospectively collected. The independent predictors for low T staging were analyzed and screened, and the Logistic regression model was constructed. An independent test set was used to validate the prediction performance of the models and compare them with the diagnostic results of sonographers.Results:Binary multivariate Logistic regression analysis showed that Emean of the mesentery around the lesion, thickness, and enlarged lymph nodes around the rectum were the independent predictors for low T staging, and the odds ratios were 1.089, 1.214, 0.183, respectively. The Logistic regression model A established by Emean, thickness and enlarged lymph nodes around the lesion and the Logistic regression model B established by Emean around the lesion had high diagnostic efficiencies (area under the ROC curve were 0.931, 0.918, respectively, the accuracy were 0.888 and 0.887, respectively). There was no significant difference in diagnostic accuracy between the two models ( P=1.000), and both models were significantly higher than that of sonographers (all P<0.001). Conclusions:SWE can effectively predict whether the tumor is of low T staging after nCRT in locally advanced rectal cancer, and can be used as an important supplement to ERUS in evaluating the T re-staging of rectal cancer after nCRT.
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[Objective]To explore the specificity and effectiveness of Medical Records Integration of Palace in Qing Dynasty for the treatment of diseases,and to provide a reference for the modern clinical external therapy.[Methods]Taking 117 fumigating and washing decoctions in Medical Records Integration of Palace in Qing Dynasty as the research object,using Excel software,the formulas,dosage,medicinal properties,and efficacy of Qinggong fumigating and washing decoctions were organized and counted.Combining with the relevant medical cases and the commentaries in the book,the use of the fumigating and washing decoctions in the Qing Palace was systematically organized.[Results]The 117 fumigating and washing decoctions in Medical Records Integration of Palace in Qing Dynasty show many features such as there are many kinds of formula,the quality of the formula is refined;the effect is strength and special focus,formula with modification according to symptoms,flexible usage of medicine,treatment first,independent use of the amount of medicine,good use of the wind-extinguishing medicinal,filling in the poisonous features when needed.It also has other advantages such as a wide range of audiences,a unique approach,sophisticated instruments,and a meticulous process of preparation of the liquid.[Conclusion]The use of the fumigating and washing decoctions in Medical Records Integration of Palace in Qing Dynasty has palace characteristics and advantages,exploring its use can gain unique insights and revelations,which helps to carry forward the characteristics of court medication and promotes the development of external therapeutic methods of traditional Chinese medicine as high research value.
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This study intends to assess the analgesic effects, physical facilitation, and safety of willow bark use in patients with arthritis. Our study was conducted based on the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement. PubMed, Scopus, EMBASE, Web of Science, Cochrane, and ClinicalTrials.gov were searched for relative randomized controlled trials (RCTs) describing the efficacy or adverse events of willow bark in patients with arthritis until 12 April 2023. We used Cochrane ROB 2.0 and the Grading of Recommendations, Assessment, Development, and Evaluations system to evaluate the quality of studies and evidence. The meta-analysis was carried out by the fix-effects model. This study included five studies with six RCTs consisting of 329 patients with arthritis. The results showed significant differences in pain relief and improvement in physical status for patients with arthritis between willow bark treatment and placebo groups, and no significant differences in the risk of all adverse events in patients with arthritis between willow bark treatment and placebo. Owing to the potential bias, the certainty and evidence of our findings are still inadequate. Therefore, further RCTs are needed to confirm our results.
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Somatic mutations accumulate in all cells with age and can confer a selective advantage, leading to clonal expansion over time. In hematopoietic cells, mutations in a subset of genes regulating DNA repair or epigenetics frequently lead to clonal hematopoiesis (CH). Here, we describe the context and mechanisms that lead to enrichment of hematopoietic stem cells (HSCs) with mutations in SRCAP, which encodes a chromatin remodeler that also influences DNA repair. We show that SRCAP mutations confer a selective advantage in human cells and in mice upon treatment with the anthracycline-class chemotherapeutic doxorubicin and bone marrow transplantation. Furthermore, Srcap mutations lead to a lymphoid-biased expansion, driven by loss of SRCAP-regulated H2A.Z deposition and increased DNA repair. Altogether, we demonstrate that SRCAP operates at the intersection of multiple pathways in stem and progenitor cells, offering a new perspective on the functional impact of genetic variants that promote stem cell competition in the hematopoietic system.
Subject(s)
Clonal Hematopoiesis , Hematopoiesis , Animals , Humans , Mice , Adenosine Triphosphatases/genetics , Adenosine Triphosphatases/metabolism , DNA Repair/genetics , Epigenesis, Genetic , Hematopoiesis/genetics , Mutation/geneticsABSTRACT
Healthy mitochondria are critical for reproduction. During aging, both reproductive fitness and mitochondrial homeostasis decline. Mitochondrial metabolism and dynamics are key factors in supporting mitochondrial homeostasis. However, how they are coupled to control reproductive health remains unclear. We report that mitochondrial GTP (mtGTP) metabolism acts through mitochondrial dynamics factors to regulate reproductive aging. We discovered that germline-only inactivation of GTP- but not ATP-specific succinyl-CoA synthetase (SCS) promotes reproductive longevity in Caenorhabditis elegans. We further identified an age-associated increase in mitochondrial clustering surrounding oocyte nuclei, which is attenuated by GTP-specific SCS inactivation. Germline-only induction of mitochondrial fission factors sufficiently promotes mitochondrial dispersion and reproductive longevity. Moreover, we discovered that bacterial inputs affect mtGTP levels and dynamics factors to modulate reproductive aging. These results demonstrate the significance of mtGTP metabolism in regulating oocyte mitochondrial homeostasis and reproductive longevity and identify mitochondrial fission induction as an effective strategy to improve reproductive health.
Subject(s)
Caenorhabditis elegans Proteins , Caenorhabditis elegans , Animals , Caenorhabditis elegans/metabolism , Mitochondria/metabolism , Aging , Reproduction , Caenorhabditis elegans Proteins/metabolism , Longevity , Guanosine Triphosphate/metabolism , Mitochondrial DynamicsABSTRACT
Benzophenone-n compounds (BPs) are applied in a broad spectrum of commercial products, one of which is sunscreen. These chemicals are frequently detected in a variety of environmental matrices worldwide, especially water bodies. BPs are defined as emerging contaminants as well as endocrine-disrupting contaminants; thus, it has become necessary to develop aggressive and green treatments to remove BPs. In this study, we used immobilised BP-biodegrading bacteria linked to reusable magnetic alginate beads (MABs). The MABs were added to a sequencing batch reactor (SBR) system to enhance the removal of 2,4-dihydroxybenzophenone (BP-1) and oxybenzone (BP-3) from sewage. The BP-1 and BP-3 biodegrading bacteria in the MABs consisted of strains from up to three genera to allow for efficient biodegradation. The strains used were Pseudomonas spp., Gordonia sp., and Rhodococcus sp. The optimal composition of the MABs consisted of 3% (w/v) alginate and 10% (w/v) magnetite. The MABs resulted in 60.8%-81.7% recovery by weight after 28 days, and there was a continuous release of bacteria. Moreover, the biological treatment of the BPs sewage improved after adding 100 g of BP1-MABs (1:27) and also 100 g BP3-MABs (1:27) into the SBR system at a hydraulic retention time (HRT) of 8 h. Compared with the SBR system without MABs, the removal rates of BP-1 and BP-3 increased from 64.2% to 71.5% and from 78.1% to 84.1%, respectively. Furthermore, the COD removal increased from 36.1% to 42.1%, and total nitrogen increased from 30.5% to 33.2%. Total phosphorus remained constant at 29%. The bacterial community analysis showed that the Pseudomonas population was <2% before the MAB addition, but increased to 56.1% by day 14. In contrast, the Gordonia sp. And Rhodococcus sp. Populations (<2%) remained unchanged throughout the 14-day treatment period.
Subject(s)
Sewage , Waste Disposal, Fluid , Sewage/chemistry , Waste Disposal, Fluid/methods , Bioreactors/microbiology , Bacteria , Nitrogen/analysis , Magnetic PhenomenaABSTRACT
Healthy mitochondria are critical for reproduction. During aging, both reproductive fitness and mitochondrial homeostasis decline. Mitochondrial metabolism and dynamics are key factors in supporting mitochondrial homeostasis. However, how they are coupled to control reproductive health remains unclear. We report that mitochondrial GTP metabolism acts through mitochondrial dynamics factors to regulate reproductive aging. We discovered that germline-only inactivation of GTP- but not ATP-specific succinyl-CoA synthetase (SCS), promotes reproductive longevity in Caenorhabditis elegans. We further revealed an age-associated increase in mitochondrial clustering surrounding oocyte nuclei, which is attenuated by the GTP-specific SCS inactivation. Germline-only induction of mitochondrial fission factors sufficiently promotes mitochondrial dispersion and reproductive longevity. Moreover, we discovered that bacterial inputs affect mitochondrial GTP and dynamics factors to modulate reproductive aging. These results demonstrate the significance of mitochondrial GTP metabolism in regulating oocyte mitochondrial homeostasis and reproductive longevity and reveal mitochondrial fission induction as an effective strategy to improve reproductive health.
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The incense sticks and cigarettes burning are key sources of particulate matter with a diameter of ≤ 2.5 µm (PM2.5) in indoor and outdoor air. While lead (Pb) isotope ratios provide valuable insights into the origin of particle pollution, their applicability for investigating these source remains unclear. The Pb isotope ratios in the PM2.5 emitted from these two sources were analyzed, and effects of brands or nicotine contents on the ratios were assessed. In addition, As, Cr, and Pb were analyzed to investigate whether Pb isotope ratios can serve as an indicator for the source investigation of these metals. We found that average ratios of 206Pb/204Pb, 206Pb/207Pb, and 208Pb/207Pb in cigarettes were heavier than those in incense sticks. Scatter plots of Pb isotope ratios indicated an overlap of values for incense sticks or cigarettes linked to different brands, in that ratios for cigarettes with high nicotine content were heavier than for those with low nicotine content. Scatter plots of As, Cr, or Pb concentration against Pb isotope ratios clearly distinguished the effects of cigarette burning versus incense sticks with respect to PM2.5 of these metals. Results indicate that brand differences did not affect the determination of PM2.5 in these two sources. We suggest that Pb isotope ratios can be a useful tool in investigating the influence of incense sticks and of cigarettes (with high or low nicotine content) burning to PM2.5 and associated metals.
Subject(s)
Air Pollutants , Air Pollution, Indoor , Tobacco Products , Particle Size , Lead , Nicotine , Air Pollution, Indoor/analysis , Particulate Matter/analysis , Isotopes , Air Pollutants/analysis , Environmental MonitoringABSTRACT
Organism aging occurs at the multicellular level; however, how pro-longevity mechanisms slow down aging in different cell types remains unclear. We generated single-cell transcriptomic atlases across the lifespan of Caenorhabditis elegans under different pro-longevity conditions (http://mengwanglab.org/atlas). We found cell-specific, age-related changes across somatic and germ cell types and developed transcriptomic aging clocks for different tissues. These clocks enabled us to determine tissue-specific aging-slowing effects of different pro-longevity mechanisms, and identify major cell types sensitive to these regulations. Additionally, we provided a systemic view of alternative polyadenylation events in different cell types, as well as their cell-type-specific changes during aging and under different pro-longevity conditions. Together, this study provides molecular insights into how aging occurs in different cell types and how they respond to pro-longevity strategies.