Exploring the relationships between exposure levels of bisphenols and phthalates and prostate cancer occurrence.

We established an ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method for simultaneously analyzing the metabolites of bisphenols and phthalates in urine to identify the associations between these exposure levels and prostate cancer (PCa) based on a case-control study. After purifying urine samples with SPE, 18 metabolites were separated on a C18 column, and MS detection was performed. The UPLC-MS/MS method has been proven effective at evaluating bisphenol and phthalate exposure (0.020-0.20 µg/L of the limits of detection, 71.8 %∼119.4 % of recoveries, 0.4 %∼8.2 % of precision). Logistic regression explored the association between exposure level and PCa in 187 PCa cases and 151 controls. The detection rates of bisphenol A (BPA) and most phthalate metabolites were 100 % ranging from 0.06-46.74 and 0.12-899.92 µg/g creatinine, respectively, while the detection rates of other bisphenols and mono-benzyl phthalate (MBzP) are low, ranging from 0 % to 21.85 %. Correlation analysis of the metabolite levels indicated that the exposure sources of BPA, di-ethyl phthalate (DEP), and di(2-ethylhexyl) phthalate (DEHP) were different, and that the exposure sources of di-n-butyl phthalate (DnBP) and di-isobutyl phthalate (DiBP) may differ between two groups. Logistic regression analysis revealed that BPA (OR<0.45 vs ≥1.43 =10.02) and DEHP exposure (OR<21.75 vs ≥45.42 =48.26) increased the risk of PCa.

Association of food insecurity with successful aging among older Indians: study based on LASI.

PURPOSE: Whether food insecurity (FI), a social determinant of health, is linked with successful aging (SA) in the older generation remains uncertain. This study explored the association of FI with SA among older Indians. METHODS: Data were collected from the Longitudinal Ageing Study in India (LASI) wave 1 (2017-2018). Older adults (≥ 60 years) who completed both the FI and the SA surveys were selected. FI was indicated by the lack of access to enough food in the past year. SA was determined by five components: (1) low probability of diseases; (2) low probability of disability; (3) high cognitive functionality; (4) low probability of depression; and (5) active social engagement. The association of FI and SA was assessed using multivariable logistic regression adjusted for potential covariates. Subgroup analyses were performed to evaluate interactions with age, sex, alcohol use, smoking, and place of residence. RESULTS: 27,579 participants met the eligibility criteria. Overall prevalence was 7.13% for FI and 19.41% for SA. Following full adjustment, FI was inversely associated with SA (OR 0.56; 95% CI 0.49-0.65) and with each of SA's five components. No significant interactions of FI and SA were observed in subgroup analyses stratified by age, sex, alcohol use, smoking, or place of residence. CONCLUSIONS: FI was inversely associated with SA among older Indians. These findings need to be validated by future studies which should also explore potential underlying mechanisms, and whether interventions decreasing FI might increase SA.

Improved atmospheric constraints on Southern Ocean CO2 exchange.

We present improved estimates of air-sea CO2 exchange over three latitude bands of the Southern Ocean using atmospheric CO2 measurements from global airborne campaigns and an atmospheric 4-box inverse model based on a mass-indexed isentropic coordinate (Mθe). These flux estimates show two features not clearly resolved in previous estimates based on inverting surface CO2 measurements: a weak winter-time outgassing in the polar region and a sharp phase transition of the seasonal flux cycles between polar/subpolar and subtropical regions. The estimates suggest much stronger summer-time uptake in the polar/subpolar regions than estimates derived through neural-network interpolation of pCO2 data obtained with profiling floats but somewhat weaker uptake than a recent study by Long et al. [Science 374, 1275-1280 (2021)], who used the same airborne data and multiple atmospheric transport models (ATMs) to constrain surface fluxes. Our study also uses moist static energy (MSE) budgets from reanalyses to show that most ATMs tend to have excessive diabatic mixing (transport across moist isentrope, θe, or Mθe surfaces) at high southern latitudes in the austral summer, which leads to biases in estimates of air-sea CO2 exchange. Furthermore, we show that the MSE-based constraint is consistent with an independent constraint on atmospheric mixing based on combining airborne and surface CO2 observations.

The association between polluted fuel use and self-reported insomnia symptoms among middle-aged and elderly Indian adults: a cross-sectional study based on LASI, wave 1.

BACKGROUND: Insomnia predisposes the aging population to reduced quality of life and poor mental and physical health. Evidence of the association between polluted fuel use and insomnia symptoms is limited and is non-existent for the Indian population. Our study aimed to explore the link between polluted fuel use and insomnia symptoms in middle-aged and older (≥ 45 years) Indian populations. METHODS: We utilized data from nationally representative Longitudinal Aging Study in India (LASI) Wave 1. Participants with complete information on fuel use, insomnia symptoms, and covariates were included. Insomnia symptoms were indicated by the presence of at least one of three symptoms: difficulty in initiating sleep (DIS), difficulty in maintaining sleep (DMS), or early morning awakening (EMA), ≥ 5 times/week. Survey-weighted multivariable logistic regression analyses were conducted to evaluate the association between polluted fuel use and insomnia symptoms. We also assessed the interaction of association in subgroups of age, gender, BMI, drinking, and smoking status. RESULTS: Sixty thousand five hundred fifteen participants met the eligibility criteria. Twenty-eight thousand two hundred thirty-six (weighted percentage 48.04%) used polluted fuel and 5461 (weighted percentage 9.90%) reported insomnia symptoms. After full adjustment, polluted fuel use was associated with insomnia symptoms (OR 1.16; 95%CI 1.08-1.24) and was linked with DIS, DMS, and EMA (OR 1.14; 95%CI 1.05-1.24, OR 1.12; 95%CI 1.03-1.22, and OR 1.15; 95%CI 1.06-1.25, respectively). No significant interactions for polluted fuel use and insomnia symptoms were observed for analyses stratified by age, sex, BMI, drinking, or smoking. CONCLUSIONS: Polluted fuel use was positively related to insomnia symptoms among middle-aged and older Indians. Suggestions are offered within this article for further studies to confirm our results, to explore underlying mechanisms, and to inform intervention strategies.

NaF-Rich Multifunctional Layers toward Stable All-Solid-State Sodium Batteries.

NASICON oxide solid electrolytes are considered promising candidates for all-solid-state sodium batteries due to their extremely high ionic conductivity and favorable electrochemical stability. However, the practical application of NASICON electrolytes is greatly impeded by poor electrolyte-electrode interfacial contact and continuous sodium dendrite propagation. Herein, a NaF-rich multifunctional interface layer on the surface of a Na anode (Na@NaF-rich), containing NaF, amorphous carbon, and an unreacted C-F bond species, is developed in situ by the reaction between Na and commercial poly(tetrafluoroethylene). This NaF-rich interface layer is proven to reduce the diffusion barriers at the Na/NASICON electrolyte interface and homogenize Na deposition as well as suppress Na dendrite growth, thus achieving a high critical current density of 4 mA cm-2. The resultant Na3V2(PO4)3@C/Na@NaF-rich all-solid-state cell showed a high initial specific capacity of 117.6 mAh g-1 at 0.1 C with a Coulombic efficiency of 94.8%. Even at 0.5 and 1 C, it still exhibited high capacity retentions of 83.3% and 80.4%, respectively, after 750 cycles.

Fluorinated Li10 GeP2 S12 Enables Stable All-Solid-State Lithium Batteries.

The instability of Li10 GeP2 S12 toward moisture and that toward lithium metal are two challenges for the application in all-solid-state lithium batteries. In this work, Li10 GeP2 S12 is fluorinated to form a LiF-coated core-shell solid electrolyte LiF@Li10 GeP2 S12 . Density-functional theory calculations confirm the hydrolysis mechanism of Li10 GeP2 S12 solid electrolyte, including H2 O adsorption on Li atoms of Li10 GeP2 S12 and the subsequent PS4 3- dissociation affected by hydrogen bond. The hydrophobic LiF shell can reduce the adsorption site, thus resulting in superior moisture stability when exposing in 30% relative humidity air. Moreover, with LiF shell, Li10 GeP2 S12 shows one order lower electronic conductivity, which can significantly suppress lithium dendrite growth and reduce the side reaction between Li10 GeP2 S12 and lithium, realizing three times higher critical current density to 3 mA cm-2 . The assembled LiNbO3 @LiCoO2 /LiF@Li10 GeP2 S12 /Li battery exhibits an initial discharge capacity of 101.0 mAh g-1 with a capacity retention of 94.8% after 1000 cycles at 1 C.

Self-reported insomnia symptoms are associated with urinary incontinence among older Indian adults: evidence from the Longitudinal Ageing Study in India (LASI).

BACKGROUND: Insomnia and urinary incontinence (UI) are both diseases burdening older adults. However, the association between them has not been well elucidated. The purpose of this study is to assess the correlation between insomnia symptoms and UI in a large community-dwelling sample of older Indian adults. METHODS: Data were from Wave 1 (2017-2018) of the Longitudinal Ageing Study of India (LASI). Male and female participants aged ≥ 60 years who provided complete information on insomnia symptoms, UI, stress UI (SUI), and covariates were included. Insomnia symptoms were identified by a report of: trouble falling asleep, waking up at night, or waking too early, ≥ 5 times/week. UI was defined by self-reported diagnosis. SUI was identified by self-report of involuntary urine leakage when sneezing, coughing, laughing, or lifting weights. Multivariable logistic regression analyses evaluated the associations between insomnia symptoms and UI and SUI. Stratified linear regression evaluated for interactions in prespecified subgroups. RESULTS: Twenty-six thousand eight hundred twenty-one LASI participants met entry criteria. 2979 (11.11%) reported insomnia symptoms, 976 (3.64%) UI, and 2726 (10.16%) SUI. After full adjustment, insomnia symptoms were associated with both UI and SUI among males (OR 1.53; 95%CI 1.20-1.96 and OR 1.51; 95%CI 1.25-1.83) and females (OR 1.53; 95% CI 1.21-1.92 and OR 1.50; 95% CI 1.31-1.73). A significant interaction effect by age was observed between insomnia symptoms and SUI among both males (p = 0.048) and females (p = 0.042). CONCLUSIONS: Insomnia symptoms were associated with UI and with SUI in both male and female older Indian adults. Further prospective study is called for to better characterize these associations and to explore underlying mechanisms.

Association between the domestic use of solid cooking fuel and increased prevalence of depression and cognitive impairment in a big developing country: A large-scale population-based study.

Background: Previous studies have suggested that air pollution affects physiological and psychological health. Using solid fuel at home is a significant source of indoor air pollution. The associations between solid fuel use and depressive symptoms and cognitive health were unclear among older adults from low- and middle-income countries (LMICs). Methods: To evaluate the association of solid fuel use with depressive symptoms and cognitive health among older adults, we obtained data from the Longitudinal Aging Study in India (LASI) and excluded subjects younger than 60 years and without critical data (solid fuel use, depressive symptoms, and cognitive health). The 10-item Center for Epidemiologic Studies Depression Scale (CES-D-10) was used to assess depressive symptoms, with more than ten indicative of depression. Cognitive health was assessed using measures from the Health and Retirement Study (HRS), and subjects with the lowest 10th percentile were considered to have cognitive impairment. The participants' responses defined solid fuel use. Multivariable logistic regression, linear regression, subgroup analysis, and interaction tests were performed to appraise the relationship between solid fuel use and depression and cognitive impairment. Results: A total of 29,789 participants over 60 years old were involved in this study. Almost half of the participants (47.5%) reported using solid fuel for home cooking. Compared with clean fuel use, solid fuel use was related to an increased prevalence of depression [odds ratio (OR) 1.09, 95% CI 1.03-1.16] and higher CES-D-10 scores (ß 0.23, 95% CI 0.12-0.35) after fully adjusted covariables. Using solid fuel was also related to a higher risk of cognitive impairment (OR 1.21, 95% CI 1.11-1.32) and a lower cognitive score (ß -0.63, 95% CI -0.79 to -0.47) compared with those who used clean fuel. In the subgroup analysis, the prevalence of depression increased in females and non-smokers. The association of solid fuel use with depression and cognitive impairment exists in subgroups of BMI, economic status, caste, living area, education, and drinking. Conclusions: The use of solid fuel at home was associated with an increased prevalence of depression and cognitive impairment among older adults in India.

The Interface Usage Skills Test: An Open Source Tool for Quantitative Evaluation in Real Time for Clinicians and Researchers.

Assistive machines endow people with limited mobility the opportunity to live more independently. However, operating these machines poses risks to the safety of the human operator as well as the surrounding environment. Thus, proper user training is an essential step towards independent control and use of functionally assistive machines. The human operator can use a variety of control interfaces to issue control signals to the device, depending on the residual mobility and level of injury of the human operator. Proficiency in operating the interface of choice precedes the skill in operating the assistive machine. In this systems paper, we present an open source tool for automatically and objectively quantifying user skill in operating various interface devices.

Clinical and epidemiological investigation of a child with asymptomatic COVID-19 infection following reoccurrence.

Objective: To investigate the case of a child infected with coronavirus disease 2019 (COVID-19) who had subsequent viral reactivation. Methods: We retrospectively analyzed the clinical manifestations, epidemiological data, laboratory and imaging examinations, treatment, and follow-up of the child. And then, we searched related literature using PubMed. Results: The 9-year-old boy was exposed to COVID-19 in Malawi and tested positive for NAT in Haikou, China. He was asymptomatic and admitted to our hospital. After six negative NATs, he was discharged from the hospital and quarantined in a hotel. His infection was reactivated again after 22 days (interval between first and last positive NATs). The cycle threshold (Ct) values of positive tests were 25 and 31, and the gene sequencing viral loads were very low. The viral strain Kenya/P2601/2020, a variant of the hCoV-19/Wuhan/IVDC-HB-01/2019 genome (GISAID accession IL: EPI_ISL_402119), was found when polymerase chain reaction enrichment was used to sequence the virus. However, people around him tested negative for COVID-19. Conclusion: First, we confirmed the reactivation of COVID-19 in a child. The risk of recurrent infection with SARS-CoV-2 was low, and the policy of strictly isolating patients carrying long-term viral ribonucleic acid should be reconsidered. The interval positivity was most likely due to incorrect sampling and/or testing methods. SGS and aB testing are recommended for children with viral reactivation. Second, SARS-CoV-2 viral reactivation cannot be ruled out. The possible mechanisms, such as prolonged infection and viral latent reactivation, need further investigation.

Impact of Changing Winds on the Mauna Loa CO2 Seasonal Cycle in Relation to the Pacific Decadal Oscillation.

Long-term measurements at the Mauna Loa Observatory (MLO) show that the CO2 seasonal cycle amplitude (SCA) increased from 1959 to 2019 at an overall rate of 0.22  ±  0.034 ppm decade-1 while also varying on interannual to decadal time scales. These SCA changes are a signature of changes in land ecological CO2 fluxes as well as shifting winds. Simulations with the TM3 tracer transport model and CO2 fluxes from the Jena CarboScope CO2 Inversion suggest that shifting winds alone have contributed to a decrease in SCA of -0.10  ±  0.022 ppm decade-1 from 1959 to 2019, partly offsetting the observed long-term SCA increase associated with enhanced ecosystem net primary production. According to these simulations and MIROC-ACTM simulations, the shorter-term variability of MLO SCA is nearly equally driven by varying ecological CO2 fluxes (49%) and varying winds (51%). We also show that the MLO SCA is strongly correlated with the Pacific Decadal Oscillation (PDO) due to varying winds, as well as with a closely related wind index (U-PDO). Since 1980, 44% of the wind-driven SCA decrease has been tied to a secular trend in the U-PDO, which is associated with a progressive weakening of westerly winds at 700 mbar over the central Pacific from 20°N to 40°N. Similar impacts of varying winds on the SCA are seen in simulations at other low-latitude Pacific stations, illustrating the difficulty of constraining trend and variability of land CO2 fluxes using observations from low latitudes due to the complexity of circulation changes.

Giant tunable Rashba spin splitting in two-dimensional polar perovskites TlSnX3 (X = Cl, Br, I).

The electronic structures and Rashba effect of two-dimensional polar tetragonal perovskites TlSnX3 (X = Cl, Br, I) are investigated by first-principles density functional theory, and intrinsic Rashba effects are found around the Γ point. In particular, TlSnI3 has the largest Rashba constant of 1.072 eV Å-1. Additionally, TlSnBr3 and TlSnI3 respond strongly to the applied electric field, and the electric field responsivity of TlSnI3 can reach 0.790 e Å2. Therefore, due to the large Rashba constants and strong electric field responses, these 2D polar perovskites are promising semiconductor materials with short channel lengths. The nano-scale short spin coherence length can keep the spin coherence of spin FETs, which is superior to the traditional 3D micron spin FETs, and will show a broad application prospect in the Rashba semiconductor field.

Overexpression of phosphatidylethanolamine-binding protein 4 (PEBP4) associates with recurrence of meningiomas.

BACKGROUND AND PURPOSE: Abnormal expression of phosphatidylethanolamine-binding protein 4 (PEBP4) has been identified in various types of malignant tumors. In the present study, we investigated the expression of PEBP4 in meningioma cases and examined whether PEBP4 expression was correlated with outcomes among these patients. MATERIALS AND METHODS: The expression levels of PEBP4 and Ki-67 in human meningioma tissues from 65 patients were evaluated by immunohistochemical staining. The correlation between PEBP4 immunoreactivity in meningioma samples and patients' clinical outcomes was examined using the Kruskal-Wallis correlation test. The prognostic value of PEBP4 expression in meningiomas patients also was investigated. RESULTS: Immunohistochemical analysis revealed up-regulated PEBP4 expression in both atypical and anaplastic meningiomas compared with classical meningiomas (13.38 ± 4.19% vs. 3.64 ± 2.04%, P < 0.001). PEBP4 immunoreactivity in meningioma samples was closely correlated with that for Ki-67 (Spearman r = 0.7922, P < 0.0001). PEBP4 expression was also associated with tumor differentiation grade and clinical recurrence (P < 0.05). Multivariate regression analysis showed with high PEBP4 expression was associated with a longer recurrence-free survival (hazard ratio=0.252, 95% confidence interval: 0.067-0.940, P = 0.040). CONCLUSION: PEBP4 may play an important role in the progression of meningioma, as high PEBP4 expression was associated with a higher pathological grade of meningioma. Moreover, PEBP4 expression may be a meaningful prognostic biomarker in meningioma.

Body mass index was linked with multi-cardiometabolic abnormalities in Chinese children and adolescents: a community-based survey.

BACKGROUND: Evidence on how body mass index (BMI) influence cardiometabolic health remains sparse in Chinese children and adolescents, especially in south China. We aim to investigate the effect of overweight and/or obesity on high blood pressure (HBP), dyslipidemia, elevated serum uric acid (SUA) and their clustering among children and adolescents in an island in South China. METHODS: Using multi-stage cluster sampling method, 1577 children and adolescents aged 7-18 in Hainan province, south China, participated in the survey. The association between body mass index and cardiometabolic indexes were explored. Overweight and obesity were classified according to criteria of World Health Organization for children and adolescents aged 5 to 19. Restricted cubic spline models were used to examine the possible non-linear association between BMI and cardiometabolic profiles. Multivariable logistic regression models were fitted to examine the effect size of BMI on cardiometabolic disorders including HBP, elevated SUA and dyslipidemia. Comorbidity of at least two cardiometabolic abnormalities (HBP, dyslipidemia, elevated SUA) was defined as clustering of cardiometabolic risk factors. RESULTS: Comparing with normal weight and underweight subjects, overweight/obese youths had higher levels of BP, SUA, triglyceride, low-density lipoprotein but lower level of high-density lipoprotein. Overweight/obese youth had higher risk of dyslipidemia (OR:2.89, 95%CI: 1.65-5.06), HBP (OR:2.813, 95%CI: 1.20-6.59) and elevated SUA (OR: 2.493, 95%CI: 1.45-4.27), respectively, than their counterparts. The sex-, age-adjusted prevalence of abnormalities clustering was 32.61% (95% CI: 20.95% to 46.92%) in overweight/obesity group, much higher than in the under/normal weight group (8.85%, 95%CI: 7.44% to 10.48%). CONCLUSION: Excess adiposity increased the risk of elevated serum uric acid, serum lipids, blood pressure and their clustering among children and adolescents in south China.

[Role and Significance of Bioactive Substances in Sputum
 in the Diagnosis of Lung Cancer].

The incidence rate of lung cancer is one of the highest incidence of malignancies in China. The gold standard for diagnosis requires pathological examination or cytological examination of biopsy. The invasive and sensitive nature of the two limits their use. Sputum contains a large number of nucleic acids and proteins, which is a good reflection of lung function. Lung cancer tissue will also affect the biological components in sputum. The detection of bioactive substances in sputum can contribute to the diagnosis of lung cancer. Based on the current research results at home and abroad, this paper reviews the bioactive substances in sputum that can be used for the diagnosis of lung cancer.
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[Carbon Monoxide and Pain Regulation: A Review].

Carbon monoxide (CO) is an endogenous gasotransmitter produced by the degradation of heme in the presence of heme oxygenase (HO) in mammals. It has been demonstrated that CO participates in a variety of physiological activities and pathological processes, and is closely related to cell protection and homeostasis maintenance in organ tissues. It has been shown by a growing number of studies that CO may play a regulatory and interventional role in the process of the occurrence and development of pain through a variety of mechanisms of action. However, its mechanism of action is still not fully understood and the uncontrollable factors concerning CO administration also placed considerable limitation to its application. This paper reviews the potential targets and pathways of CO in pain regulation and discusses the challenges and opportunities in the clinical application of CO in order to provide suggestions for further exploration and development of CO analgesics.

Effect of fat mass index, fat free mass index and body mass index on childhood blood pressure: a cross-sectional study in south China.

BACKGROUND: Evidence on how different body composition indexes, such as body mass index (BMI), fat mass index (FMI) and fat free mass index (FFMI), influence blood pressure (BP) in Chinese children and adolescents is sparse. The aim of this study is to assess the effect of different body composition on BP in participants aged 7-18 in south China. METHODS: A cross-sectional study was conducted in 2013. A total of 1,609 children and adolescents from urban and rural areas in Hainan Province, South China, were selected using multi-stage stratified cluster sampling method. Each participant underwent anthropometric and BP tests. BMI, FMI and FFMI were calculated and analyzed as body composition indexes. RESULTS: In the population level stratified by sex, FFMI had the highest r-value (Partial Spearman correlations) of correlation with systolic BP in boys (rs=0.305, P<0.001) and girls (rs=0.237, P<0.001). FMI was found to have the highest r-value of correlation with DBP in boys (rs=0.154, P<0.001). The quantile regression model indicated that, within each age group, all body composition indexes was positively associated with systolic BP, and FFMI has the greatest value of regression coefficient (4.38, 95% CI: 3.81-4.95). But for diastolic BP, positive associations with BMI, FMI and FFMI were only observed in the 11-12 years group. Restrict cubic spline models showed that there were both linear and non-linear relations between BMI, FMI and BP, but for FFMI, there was only linear association with BP. CONCLUSIONS: The relation between BP and FFMI was stronger than with BMI and FMI. Combined measurement of body composition should be considered to help health professionals interpret body mass data from children and adolescents with varied stature and age.

Epidemiological investigation of a COVID-19 family cluster outbreak transmitted by a 3-month-old infant.

OBJECTIVE: To investigate the clinical characteristics, epidemiological characteristics, and transmissibility of coronavirus disease 2019 (COVID-19) in a family cluster outbreak transmitted by a 3-month-old confirmed positive infant. METHODS: Field-based epidemiological methods were used to investigate cases and their close contacts. Real-time fluorescent reverse transcription polymerase chain reaction (RT-PCR) was used to detect Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) for all collected specimens. Serum SARS-CoV-2 IgM and IgG antibodies were detected by Chemiluminescence and Gold immnnochromatography (GICA). RESULTS: The outbreak was a family cluster with an attack rate of 80% (4/5). The first case in this family was a 3-month-old infant. The transmission chain was confirmed from infant to adults (her father, mother and grandmother). Fecal tests for SARS-CoV-2 RNA remained positive for 37 days after the infant was discharged. The infant's grandmother was confirmed to be positive 2 days after the infant was discharged from hospital. Patients A (3-month-old female), B (patient A's father), C (patient A's grandmother), and D (patient A's mother) had positive serum IgG and negative IgM, but patients A's grandfather serum IgG and IgM were negative. CONCLUSION: SARS-CoV-2 has strong transmissibility within family settings and presence of viral RNA in stool raises concern for possible fecal-oral transmission. Hospital follow-up and close contact tracing are necessary for those diagnosed with COVID-19.

Interactions of Zinc Oxide Nanostructures with Mammalian Cells: Cytotoxicity and Photocatalytic Toxicity.

This article presents a state-of-the-art review and analysis of literature studies on the morphological structure, fabrication, cytotoxicity, and photocatalytic toxicity of zinc oxide nanostructures (nZnO) of mammalian cells. nZnO with different morphologies, e.g., quantum dots, nanoparticles, nanorods, and nanotetrapods are toxic to a wide variety of mammalian cell lines due to in vitro cell-material interactions. Several mechanisms responsible for in vitro cytotoxicity have been proposed. These include the penetration of nZnO into the cytoplasm, generating reactive oxygen species (ROS) that degrade mitochondrial function, induce endoplasmic reticulum stress, and damage deoxyribonucleic acid (DNA), lipid, and protein molecules. Otherwise, nZnO dissolve extracellularly into zinc ions and the subsequent diffusion of ions into the cytoplasm can create ROS. Furthermore, internalization of nZnO and localization in acidic lysosomes result in their dissolution into zinc ions, producing ROS too in cytoplasm. These ROS-mediated responses induce caspase-dependent apoptosis via the activation of B-cell lymphoma 2 (Bcl2), Bcl2-associated X protein (Bax), CCAAT/enhancer-binding protein homologous protein (chop), and phosphoprotein p53 gene expressions. In vivo studies on a mouse model reveal the adverse impacts of nZnO on internal organs through different administration routes. The administration of ZnO nanoparticles into mice via intraperitoneal instillation and intravenous injection facilitates their accumulation in target organs, such as the liver, spleen, and lung. ZnO is a semiconductor with a large bandgap showing photocatalytic behavior under ultraviolet (UV) light irradiation. As such, photogenerated electron-hole pairs react with adsorbed oxygen and water molecules to produce ROS. So, the ROS-mediated selective killing for human tumor cells is beneficial for cancer treatment in photodynamic therapy. The photoinduced effects of noble metal doped nZnO for creating ROS under UV and visible light for killing cancer cells are also addressed.