ß-Hydroxybutyrate Protects Against Cisplatin-Induced Renal Damage via Regulating Ferroptosis.

Cisplatin is a particularly potent antineoplastic drug. However, its usefulness is restricted due to the induction of nephrotoxicity. More recent research has indicated that ß-hydroxybutyrate (ß-HB) protects against acute or chronic organ damage as an efficient healing agent. Nonetheless, the therapeutic mechanisms of ß-HB in acute kidney damage caused by chemotherapeutic drugs remain unclear. Our study developed a model of cisplatin-induced acute kidney injury (AKI), which involved the administration of a ketogenic diet or ß-HB. We analyzed blood urea nitrogen (BUN) and creatinine (Cr) levels in serum, and used western blotting and immunohistochemical staining to assess ferroptosis and the calcium/calmodulin-dependent kinase kinase 2 (Camkk2)/AMPK pathway. The mitochondrial morphology and function were examined. Additionally, we conducted in vivo and in vitro experiments using selective Camkk2 inhibitor or activator to investigate the protective mechanism of ß-HB on cisplatin-induced AKI. Exogenous or endogenous ß-HB effectively alleviated cisplatin-induced abnormally elevated levels of BUN and Cr and renal tubular necrosis in vivo. Additionally, ß-HB reduced ferroptosis biomarkers and increased the levels of anti-ferroptosis biomarkers in the kidney. ß-HB also improved mitochondrial morphology and function. Moreover, ß-HB significantly attenuated cisplatin-induced cell ferroptosis and damage in vitro. Furthermore, western blotting and immunohistochemical staining indicated that ß-HB may prevent kidney injury by regulating the Camkk2-AMPK pathway. The use of the Camkk2 inhibitor or activator verified the involvement of Camkk2 in the renal protection by ß-HB. This study provided evidence of the protective effects of ß-HB against cisplatin-induced nephrotoxicity and identified inhibited ferroptosis and Camkk2 as potential molecular mechanisms.

ß-HB protects against cisplatin-induced renal damage both in vivo and in vitro.Moreover, ß-HB is effective in attenuating cisplatin-induced lipid peroxidation and ferroptosis.The regulation of energy metabolism, as well as the treatment involving ß-HB, is associated with Camkk2.

Gut microbiota mediates the protective effects of ß-hydroxybutyrate against cisplatin-induced acute kidney injury.

The gut microbiota has been reported to be perturbed by chemotherapeutic agents and to modulate side effects. However, the critical role of ß-hydroxybutyrate (BHB) in the regulation of the gut microbiota and the pathogenesis of chemotherapeutic agents related nephrotoxicity remains unknown. We conducted a comparative analysis of the composition and function of gut microbiota in healthy, cisplatin-challenged, BHB-treated, and high-fat diet-treated mice using 16 S rDNA gene sequencing. To understand the crucial involvement of intestinal flora in BHB's regulation of cisplatin -induced nephrotoxicity, we administered antibiotics to deplete the gut microbiota and performed fecal microbiota transplantation (FMT) before cisplatin administration. 16 S rDNA gene sequencing analysis demonstrated that both endogenous and exogenous BHB restored gut microbiota dysbiosis and cisplatin-induced intestinal barrier disruption in mice. Additionally, our findings suggested that the LPS/TLR4/NF-κB pathway was responsible for triggering renal inflammation in the gut-kidney axis. Furthermore, the ablation of the gut microbiota ablation using antibiotics eliminated the renoprotective effects of BHB against cisplatin-induced acute kidney injury. FMT also confirmed that administration of BHB-treated gut microbiota provided protection against cisplatin-induced nephrotoxicity. This study elucidated the mechanism by which BHB affects the gut microbiota mediation of cisplatin-induced nephrotoxicity by inhibiting the inflammatory response, which may help develop novel therapeutic approaches that target the composition of the microbiota.

Clinical diagnostic value of IL-14, 1L-16 and SAA in periodontitis.

OBJECTIVES: Periodontitis is a chronic infectious disease, which leads to inflammatory destruction of periodontal supporting tissues. Interleukin 14 (IL-14), Interleukin 16 (IL-16) and serum amyloid A (SAA) have been demonstrated to be abnormally expressed in inflammatory diseases. Therefore, this study was performed to analyzed the expression and potential clinical values of IL-14, 1L-16 and SAA in periodontitis. MATERIALS AND METHODS: A total of 100 periodontitis patients and 100 healthy volunteers were recruited and the saliva and serum samples were collected. Then the C-reactive protein (CRP), procalcitonin (PCT), IL-14, 1L-16 and SAA levels in the saliva and serum of periodontitis patients were measured by Elisa kits. Besides, the significance of CRP, PCT, IL-14, 1L-16 and SAA in periodontitis patients were analyzed by receiver operating characteristic (ROC) analysis. RESULTS: The results showed that CRP, PCT, IL-14, 1L-16 and SAA levels were significantly increased in the the saliva and serum of the periodontitis patients. Additionally, the area under the curve (AUC) of saliva CRP, PCT, IL-14, 1L-16 and SAA for the diagnosis of periodontitis were 0.9035, 0.9435, 0.9508, 0.9500 and 0.9467, respectively. The AUC of serum CRP, PCT, IL-14, 1L-16 and SAA for the diagnosis of periodontitis were 0.9035, 0.9435, 0.9508, 0.9500 and 0.9467, respectively. What's more, the diagnostic value of IL-14, 1L-16 and SAA were enhanced when combining with CRP and PCT. CONCLUSION AND CLINICAL RELEVANCE: This study demonstrated that IL-14, IL-16 and SAA expressions were upregulated in periodontitis patients and exhibited a significant significance for periodontitis diagnosis.

Doping Engineering to Modulate Lattice and Electronic Structure for Enhanced Piezocatalytic Therapy and Ferroptosis.

Piezocatalytic therapy, which generates reactive oxygen species (ROS) under mechanical force, has garnered extensive attention for its use in cancer therapy owing to its deep tissue penetration depth and less O2 -dependence. However, the piezocatalytic therapeutic efficiency is limited owing to the poor piezoresponse, low separation of electron-hole pairs, and complicated tumor microenvironment (TME). Herein, a biodegradable, porous Mn-doped ZnO (Mn-ZnO) nanocluster with enhanced piezoelectric effect is constructed via doping engineering. Mn-doping not only induces lattice distortion to increase polarization but also creates rich oxygen vacancies (OV ) for suppressing the recombination of electron-hole pairs, leading to high-efficiency generation of ROS under ultrasound irradiation. Moreover, Mn-doped ZnO shows TME-responsive multienzyme-mimicking activity and glutathione (GSH) depletion ability owing to the mixed valence of Mn (II/III), further aggravating oxidative stress. Density functional theory calculations show that Mn-doping can improve the piezocatalytic performance and enzyme activity of Mn-ZnO due to the presence of OV . Benefiting from the boosting of ROS generation and GSH depletion ability, Mn-ZnO can significantly accelerate the accumulation of lipid peroxide and inactivate glutathione peroxidase 4 (GPX4) to induce ferroptosis. The work may provide new guidance for exploring novel piezoelectric sonosensitizers for tumor therapy.

Longitudinal study of multidimensional factors influencing maternal and offspring health outcomes: a study protocol.

BACKGROUND: Reducing preventable adverse maternal and offspring outcomes is a global priority. The causes of adverse maternal and fetal outcomes are complex with multidimensional influencing factors. In addition, the Covid-19 epidemic has had a significant psychological and physical impact on people. China is now stepping into the post-epidemic era. We are curious about the psychological and physical situation of maternity in China at this stage. Therefore, we plan to initiate a prospective longitudinal study to investigate the multidimensional influences and mechanisms that affect maternal and offspring health. METHOD: We will recruit eligible pregnant women at Renmin Hospital of Hubei Province, China. The expected sample size is 1490. We will assess socio-demographics, Covid-19 related information, social capital, sleep, mental health and medical records, including clinical examination and biochemical tests. Eligible pregnant women will be enrolled in the study with less than 14 weeks of gestation. Participants will receive a total of nine follow-up visits between mid-pregnancy and one year postpartum. The offspring will be followed up at birth, 6 weeks, 3 months, 6 months and one year. In addition, a qualitative study will be conducted to understand the underlying causes that affect maternal and offspring health outcomes. DISCUSSION: This is the first longitudinal study of maternity in Wuhan, Hubei Province which integrates physical, psychological and social capital dimensions. Wuhan is the first city to be affected by Covid-19 in China. As China moves into the post-epidemic era, this study will provide us with a better understanding of the long-term impact of the epidemic on maternal and offspring health outcomes. We will implement a range of rigorous measures to enhance participants' retention rate and ensure the quality of data. The study will provide empirical results for maternal health in the post-epidemic era.

Recent Progresses in Non-Dialysis Chronic Kidney Disease Patients with Hyperkalemia: Outcomes and Therapeutic Strategies.

Chronic kidney disease (CKD) affects about 10% of the world's population. Hyperkalemia is a life-threatening complication in patients with CKD, as it is associated with adverse cardiovascular and kidney outcomes. There are still many challenges and questions to address to improve the currently available therapeutic strategies to treat hyperkalemia, such as how to approach the emergency management of hyperkalemia. In recent years, in addition to novel oral potassium binders, great progress has been made in the application of novel kidney protective strategies, such as mineralocorticoid receptor antagonists and sodium-glucose cotransporter 2 inhibitors (SGLT2i) in hyperkalemia therapy. This review will discuss the recent advances from clinical trials in the effective management of hyperkalemia in non-dialysis CKD patients, enhancing the knowledge of physicians and internists concerning these newer agents and providing a helpful reference for clinical practice.

Optimal gestational weight gain in Chinese pregnant women with gestational diabetes mellitus: A large retrospective cohort study.

AIM: To examine the optimal gestational weight gain (GWG) for Chinese pregnant women with gestational diabetes mellitus (GDM) based on the Chinese-specific body mass index (BMI) classification. METHODS: A retrospective cohort study was conducted using the 2017-2020 data from pregnant women with GDM in a tertiary hospital. A quadratic function model and the total predicted probability of adverse pregnancy outcomes were developed to obtain the optimal GWG. Differences in the incidence of adverse pregnancy outcomes between our optimal GWG recommendations and the Institute of Medicine (IOM) 2009 GWG guidelines were also analyzed. RESULTS: A total of 8103 pregnant women with GDM were analyzed. Based on the Chinese-specific BMI classification, the optimal GWG range was 11.0-17.5 kg for underweight women, 3.7-9.7 kg for normal-weight women, -0.6 to 4.8 kg for overweight women, and - 9.8 to 4.2 kg for obese women. Excessive GWG had a higher risk of large for gestational age (LGA) (OR: 2.99, 95% CI: 2.42-3.70), macrosomia (OR: 2.35, 95% CI: 1.77-3.12), pre-eclampsia (OR: 1.91, 95% CI: 1.37-2.65), gestational hypertension (OR: 1.65, 95% CI: 1.24-2.19), cesarean section (OR: 1.29, 95% CI: 1.15-1.44), postpartum hemorrhage (OR: 1.29, 95% CI: 1.02-1.64); insufficient GWG had a higher risk of small for gestational age (OR: 1.82, 95% CI: 1.20-2.75). Compared to the IOM 2009 GWG guidelines, the prevalence of macrosomia, LGA, and postpartum hemorrhage were significantly lower in pregnant women following the implementation of our recommended GWG range (p < 0.05). CONCLUSIONS: Compared to the IOM 2009 GWG recommendations, our optimal GWG recommendations for Chinese pregnant women were more sensitive.

Association between neonatal hyperbilirubinemia and hypoglycemia in Chinese women with diabetes in pregnancy and influence factors.

This retrospective study aimed to investigate the correlation between neonatal hyperbilirubinemia (NHB) and hypoglycemia (NH) in Chinese women with diabetes in pregnancy (DIP), and the influencing factors. All the data were collected July 1, 2017 and June 30, 2020, and 10,558 Chinese women with DIP and live births were included. Two separate multivariate binary stepwise forward logistic regression analysis calculated OR with 95% CI. The prevalence rates of NHB and NH was respectively 3.65% and 5.82% among women with DIP. The comorbidity of both diseases was 0.59%. NH were 1.81 times (OR 1.81, 1.19-2.76) more likely to have hyperbilirubinemia. NHB is positively correlated with NH (OR 1.93, 1.27-2.92). Increased gestational age has a protective effect on both NH (OR 0.76, 0.68-0.85) and NHB (OR 0.80, 0.69-0.92). Abnormal placental morphology is related to NH (OR 1.55, 1.16-2.08) and NHB (OR 1.64, 1.10-2.45). Regarding neonatal outcomes, congenital heart disease (CHD) (OR 2.16, 1.25-3.73; and OR 10.14, 6.47-15.90) was a risk factor for NH and NHB. NHB and NH were significantly correlated in women with DIP. The offspring of DIP with multiple risk factors have a significantly increased risk of neonatal hyperbilirubinemia.

Is the Gestational Weight Gain Recommended by the National Academy of Medicine Guidelines Suitable for Chinese Twin-Pregnant Women with Gestational Diabetes Mellitus?

OBJECTIVES: This study aimed to assess the applicability of the National Academy of Medicine (NAM) interim guidelines for twin pregnancies to the specific population of gestational diabetes mellitus by exploring the relationship between gestational weight gain and adverse pregnancy outcomes in Chinese twin-pregnant women with gestational diabetes mellitus. STUDY DESIGN: This was a retrospective cohort study of women diagnosed with diabetes in pregnancy between July 2017 and December 2020 at the Maternal and Child Health Hospital in Chongqing, China. The primary variable of interest was maternal total gestational weight gain. The primary outcomes were perinatal outcomes, which included: preeclampsia, small for gestational age, large for gestational age, low birth weight, neonatal pneumonia, neonatal respiratory distress syndrome, and neonatal intensive unit admission, etc. The association between inappropriate gestational weight gain and adverse pregnancy outcomes was estimated using multiple logistic regression analysis. RESULTS: A total of 455 twin-pregnant women who had gestational diabetes mellitus were analyzed. Women with low gestational weight gain had reduced risk of preeclampsia (adjusted odds ratio [aOR], 0.32; 95% CI or confidence interval, 0.17-0.63; p = 0.001) and their infants had higher risks of small for gestational age (aOR, 1.93; 95% CI, 1.04-3.58; p = 0.037), low birth weight (aOR, 2.27; 95% CI, 1.32-3.90; p = 0.003), neonatal intensive unit admission (aOR, 3.29; 95% CI, 1.10-5.78; p = 0.038), pneumonia (aOR, 2.41; 95% CI, 1.08-5.33; p = 0.031), and neonatal respiratory distress syndrome (aOR, 2.29; 95% CI, 1.10-4.78; p = 0.027); the infants of women with excessive gestational weight gain had a higher risk of large for gestational age (aOR, 3.76; 95% CI, 1.42-9.96; p = 0.008). CONCLUSION: Gestational weight gain controlled within the range recommended by the NAM could reduce the risk of perinatal adverse outcomes. The 2009 NAM gestational weight gain recommendations can be used for Chinese twin-pregnant women with gestational diabetes mellitus. KEY POINTS: · Inappropriate gestational weight gain can lead to adverse perinatal outcomes in twin pregnancies.. · Gestational weight gain controlled within recommended range could reduce the risk of poor perinatal outcomes.. · The National Academy of Medicine recommendations are suitable for Chinese twin-pregnant women with GDM..

Acute Kidney Injury Induced by Immune Checkpoint Inhibitors.

Background: Recent advances in immune therapy have focused on several agents that target tumor suppression; specifically, use of immune checkpoint inhibitors (ICIs), such as ipilimumab, pembrolizumab, and nivolumab, has become an important strategy in cancer therapy as they improve outcomes in malignant disease. However, the incidence of renal complications arising from the widespread use of ICIs may be underestimated. Summary: The most frequently reported renal condition caused by ICI use is acute interstitial nephritis, and for clinicians, the crucial question is how to effectively manage patients who develop renal side effects due to cancer treatment. Currently, treatment of kidney injury associated with ICIs adheres to clinical guidelines described in Kidney Disease Improving Global Outcomes, which entails drug withdrawal and glucocorticoids or combined immunosuppressant use based on disease stage; however, there is no consensus on renal biopsy. Key Messages: Despite significant progress in prevention and treatment, the incidence and mortality of ICI-induced acute kidney injury (AKI) remain very high. This article will discuss the general clinical manifestations, mechanisms of toxicity, renal complications of ICI therapy, and related biomarkers of renal damage. It is envisaged that this information would help clinicians effectively manage AKI due to ICI therapy.

Impact of hepatitis B virus infection on maternal and infant outcomes of women with gestational diabetes mellitus: A three-year retrospective study.

AIMS: To explore the impact of HBV infection on maternal and infant outcomes of GDM women. METHODS: We retrospectively identified 8126 women with GDM in China from July 2017 to June 2020, and divided them into GDM with HBV infection group (n = 483) and GDM with non-HBV infection group (n = 7643). Two sample t-test and Chi-square test were used to compare differences between groups. Logistic regression models were used to explore the association between HBV infection and maternal and infant outcomes. RESULTS: Placental abruption (PA), (2.3% vs. 1.0%, P = 0.008), placenta previa (4.3% vs. 2.8% p = 0.044), intrahepatic cholestasis of pregnancy (ICP), (6.4% vs. 3.0%, P < 0.001), cesarean section (52.0% vs. 46.0%, P = 0.011), fetal chromosomal abnormalities (1.2% vs. 0.4%, P = 0.021), and neonatal hyperglycemia (1.9% vs. 3.6%, P = 0.047) were more likely to occur in GDM with HBV infection group. After adjusting for the covariates, HBV infection was found to be associated with ICP (aOR, 2.35; 95% CI: [1.58-3.50]), PA (aOR, 2.34; 95% CI: 1.22-4.47), and fetal chromosomal abnormalities (aOR, 2.88; 95% CI: 1.18-7.03). CONCLUSIONS: HBV infection was associated with part of maternal and infant outcomes in the GDM population.

Adsorption and diffusion of alkali metals (Li, Na, and K) on heteroatom-doped monolayer titanium disulfide.

Doping engineering is an effective modification strategy to enhance the electrochemical performance of electrode materials. In this paper, the impacts of heteroatom doping in monolayer titanium disulfide (TiS2) by substituting the S atom with the heteroatoms (B, C, N, O, F, and P) on the adsorption and diffusion capabilities of alkali metals (Li, Na, and K) have been systematically investigated using first-principles calculations to evaluate the material performance for application in alkali metal-ion batteries. The doping of most heteroatoms can promote the adsorption capability of alkali metal atoms on monolayer TiS2 as their adsorption energies decrease compared with the pristine system, particularly for p-type doping with C, N, and P. The diffusion energy barriers decrease when alkali metals approach the doping site of most heteroatom-doped TiS2, and the barriers near the doping site are extremely small (0.00-0.08 eV), whereas they slightly increase as alkali metals move away from the doping site. P doping has the lowest overall diffusion energy barrier for each metal. Thus, monolayer TiS2 with heteroatom doping, especially P doping, can be used as a potential anode material for alkali metal-ion batteries. This study can help comprehend the impacts of heteroatom doping and design high-performance electrode materials for rechargeable batteries.

Glutathione Conjugation and Protein Adduction by Environmental Pollutant 2,4-Dichlorophenol In Vitro and In Vivo.

2,4-Dichlorophenol (2,4-DCP), an environmental pollutant, was reported to cause hepatotoxicity. The biochemical mechanisms of 2,4-DCP induced liver injury remain unknown. The present study showed that 2,4-DCP is chemically reactive and spontaneously reacts with GSH and bovine serum albumin to form GSH conjugates and BSA adducts. The observed conjugation/adduction apparently involved the addition of GSH and departure of chloride via the ipso substitution pathway. Two biliary GSH conjugates and one urinary N-acetyl cysteine conjugate were observed in rats given 2,4-DCP. The N-acetyl cysteine conjugate was chemically synthesized and characterized by mass spectrometry and NMR. As expected, 2,4-DCP was found to modify hepatic protein at cysteine residues in vivo by the same chemistry. The observed protein adduction reached its peak at 15 min and revealed dose dependency. The new findings allowed us to better understand the mechanisms of the toxic action of 2,4-DCP.

Lithium-ion storage in molybdenum phosphides with different crystal structures.

Transition metal phosphides have been receiving a great deal of attention as anode materials for Li-ion batteries due to their novel properties of high theoretical capacity and relatively low polarization. MoP and MoP2 nanoparticles with different crystal structures are synthesized by phosphorization in different stoichiometric proportions, using Mo nanospheres as the precursor produced by the plasma evaporation method. When used as the anode material for Li-ion batteries, the MoP2 electrode delivers a stable capacity of 676.60 mA h g-1 after 300 cycles at a current density of 0.1 A g-1 with obvious discharge/charge plateaus; however, the capacity of the hexagonal MoP electrode is 312.38 mA h g-1. The first-principles calculations illustrate that the di-phosphorus bond of MoP2 is prone to break and the distal P atoms preferentially bind with Li atoms to form Li3P during lithiation, but MoP prefers to form ternary LixMoP. The ex situ X-ray diffraction (XRD) and high resolution transmission electron microscopy (HRTEM) of the MoP2 electrode after cycling confirm the conversion reaction for the electrochemical storage of Li-ions.

Lack of association between PAX6/SOSTDC1/FAM20B gene polymorphisms and mesiodens.

BACKGROUND: The purpose of this study was to analyze the association between the genetic polymorphism of genes (PAX6, SOSTDC1and FAM20B) and the susceptibility to mesiodens. METHODS: This study was carried out on 50 patients with mesiodens and 50 controls. The family history of each patient with mesiodens were recorded. Genomic DNA was extracted from saliva samples, and single nucleotide polymorphisms were detected in all exons and exon/intron boundaries of PAX6, SOSTDC1 and FAM20B using Sanger sequencing. The data were analyzed using pearson chi-square test with theoretical frequency ≥ 5. For theoretical frequency less than 5 but at least 1 (≤20% cell), the data were analyzed by continuity correction. For the rest, Fisher's Exact test was used. A P-value< 0.05 was considered statistically significant. The Odds ratio (OR) and confidence intervals (CI) were recorded. RESULTS: Three polymorphisms were detected in PAX6. Two polymorphisms were detected in SOSTDC1. Twenty-nine polymorphisms were detected in FAM20B. Although, the T allele of FAM20B (rs3766626) appears to be associated with mesiodens (P = 0.051), there were no significant differences of PAX6/SOSTDC1/FAM20B gene polymorphisms between the two groups. The T allele of FAM20B (rs3766626) was associated with susceptibility to two mesiodens (P < 0.001; OR = 8.333; CI = 2.516-27.600). CONCLUSIONS: Lack of association between PAX6/SOSTDC1/FAM20B gene polymorphisms and mesiodens in the population studied was detected. Further studies with large samples on T allele of FAM20B (rs3766626) are needed.

Mechanism of Rhodium(III)-Catalyzed C-H Activation/Annulation of Aromatic Amide with α-Allenol: A Computational Study.

With the help of DFT calculations, the reaction mechanisms of the rhodium(III)-catalyzed C-H activation/annulation between aromatic amide and α-allenol leading to the formation of isoindolinone have been theoretically investigated. Our calculated results show that the catalytic cycle consists of four stages: N-H deprotonation and C-H activation (Stage I), allene insertion, rearrangement and isomerization (Stage II), ß-H elimination and enol-keto tautomerism (Stage III), and catalyst regeneration resulting in the five-membered ring product (Stage IV). For stage IV, besides the reaction paths proposed by the experimentalists, i.e., the insertion and reductive elimination (labeled as path a) and the reductive elimination and hydroamination (labeled as path b), an alternative path which involves C-N and C-H reductive eliminations (labeled as path c) was proposed and examined. The computational results show that the newly established path c is more energetically favorable than the reaction paths proposed by the experimentalists (paths a and b). The allene (non-terminal double bond) insertion step contributes to the rate-determining step with an overall activation free energy of 24.6 kcal/mol. Our study is beneficial for a better comprehension of the reaction mechanisms and provides a significant suggestion for further development of similar reactions.

Modulation and effects of surface groups on photoluminescence and photocatalytic activity of carbon dots.

To demonstrate the effects of surface atoms on photoluminescence (PL) and photocatalytic activities of luminescent carbon dots (CDs), we design and tailor the surface groups of CDs with heteroatoms by a facile and effective approach. The coexistence of O and N radicals in CDs results in strong PL while CDs containing O and Cl radicals show high photocatalytic activity. This is attributed to the different degrees and directions of energy band bending from inner to surface induced by O, N, and Cl radicals at the surface of CDs. The coexistence of both upward and downward band bending that are caused by the O and Cl radicals, respectively, in CDs is similar to an internal electronic field that facilitates the separation of electron-hole pairs and carrier migration, leading to high photocatalytic activity. These results may also be used for designing and tailoring optical-electronic properties of carbon nanostructures.

Chemical regulation of carbon quantum dots from synthesis to photocatalytic activity.

Carbon quantum dots (CQDs) were synthesized by heating various carbon sources in HNO3 solution at reflux, and the effects of HNO3 concentration on the size of the CQDs were investigated. Furthermore, the oxygen-containing surface groups of as-prepared CQDs were selectively reduced by NaBH4 , leading to new surface states. The experimental results show that the sizes of CQDs can be tuned by HNO3 concentration and then influence their photoluminescent behaviors; the photoluminescent properties are related to both the size and surface state of the CQDs, but the photocatalytic activities are determined by surface states alone. The different oxygen-containing groups on the surface of the CQDs can induce different degrees of the band bending upward, which determine the separation and combination of the electron-hole pairs. The high upward band bending, which is induced by C=O and COOH groups, facilitates separation of the electron-hole pairs and then enhances high photocatalytic activity. In contrast, the low upward band bending induced by C-OH groups hardly prevents the electron-hole pairs from surface recombination and then exhibits strong photoluminescence. Therefore, both the photocatalytic activities and optical properties of CQDs can be tuned by their surface states.

[Clinical investigation of the diagnostic value of interferon-gamma, interleukin-12 and adenosine deaminase isoenzyme in tuberculous pleurisy].

OBJECTIVE: To investigate the diagnostic value of interferon-gamma (IFN-gamma), interleukin-12 (IL-12) and adenosine deaminase isoenzymes (ADA(2)) in tuberculous pleural effusions. METHODS: One hundred and ninety specimens of pleural effusion were collected from 190 patients with pleural effusion in Peking University People's Hospital, Beijing Chest Hospital, and Beijing Tuberculosis and Thoracic Tumor Institute, from March 2002 to February 2003. Of them 141 pleural specimens were diagnosed as tuberculous, and 49 as malignant. IFN-gamma and IL-12 concentrations and ADA isoenzyme activity in all the specimens were determined by ELISA and enzyme kinetic analytical method respectively. RESULTS: (1) ADA(2) activity (47.9 +/- 6.9) U/L in tuberculous effusions was significantly higher than that in malignant effusion (13.2 +/- 3.2) U/L (P < 0.01). The IFN-gamma level (112.1 +/- 45.8) ng/L in tuberculous effusion was significantly higher than that in malignant diseases (24.8 +/- 5.9) ng/L (P < 0.01). The IL-12 level (104.3 +/- 32.3) ng/L in tuberculous effusions was significantly higher than that in malignant diseases (61.8 +/- 10.8) ng/L (P < 0.05). (2) By analysis of ROC curves, the cut-off values for IFN-gamma, IL-12 and ADA(2) were defined. The sensitivity and specificity of IFN-gamma for tuberculous effusion were 84.4% and 95.9% respectively. Those of IL-12 for tuberculous effusion were 85.1% and 65.3% respectively, while those of ADA(2) were 84.4% and 91.8%. CONCLUSIONS: IFN-gamma and IL-12 could be used as valuable parameters for the differentiation of tuberculous effusion from malignant, and IFN-gamma was more sensitive and specific for tuberculous effusion than IL-12 and ADA(2).