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BACKGROUND This article reviewed the research progress of pretreatment techniques for the analysis of precious metal elements in geological samples in recent years. The fire assay, alkali fusion, acid decomposition and adsorption methods used in the separation and enrichment of samples and absorption, tellurium co-precipitation, ion exchange, solvent extraction, distillation, and biosorption methods commonly used for sample decomposition were reviewed. The characteristics and deficiencies of each method were investigated, and the future development direction of the method is prospected. OBJECTIVES In order to make the analysis results accurate and reliable, it is necessary to select the appropriate means of sample decomposition and separation and enrichment to ensure complete sample decomposition, effectively eliminate the interference of co-existing ions and matrix effect, enhance the precious metal element test signal, and improve the signal-to-noise ratio. METHODS The fire assay method used for sample decomposition has been continuously explored and improved by analysts, and has become the best method to decompose precious metals. However, it still has the disadvantages of large reagent consumption, high cost, and long procedure. Although the alkali fusion method can decompose almost all geological samples, the resulted solution contained a large amount of sodium salt, which needed to be further purified. The acid decomposition method was mainly based on the high-pressure sealed Carius tube digestion, but it was limited by the nature of the sample. Different separation and enrichment methods were highly targeted. For example, the adsorption method was mostly used for the enrichment of Au, Pt, and Pd. The distillation method was only suitable for the analysis of Os and Ru. RESULTS Precious metal elements had features such as strong particle effects, complex and diverse forms, and ultra-trace amounts, so it was necessary to choose a suitable pretreatment method according to the type of samples. CONCLUSIONS Based on the existing precious metal decomposition methods, in combination with the current new experimental equipment and conditions, more efficient and rapid decomposition technologies should be sought and the background of the procedure and pollution problems in each step strictly controlled, realizing multi-technology and multi-method integration and meeting the requirements of precious metal analysis.

Black rock as an important carrier of platinum group elements was discovered in recent years. Due to the multiple origins and complex mineralization, the distribution and occurrence of platinum group elements in black rock are not clear, which is also the major reason why the analytical results of platinum group elements are unstable. According to the mineral properties and composition of black rock, the occurrences of Pt, Pd and Au in black rock could be divided into exchangeable phase, organic binding phase, sulfide bounding phase, and residue phase. The adsorption of Pt, Pd and Au from the organic carbon in black rocks was inhibited by adding potassium thiocyanate and sodium cyanide as desorbents. The distribution of Pt, Pd and Au in each phase was identified by Inductively Coupled Plasma-Mass Spectrometry (ICP-MS). The results show that: (1) The ratios of the total extraction of each phase to the total amount of the element are 94.4%-101.0% for Pt, 95.8%-101.0% for Pd, and 96.7%-102.0% for Au, indicating good accuracy and reproducibility. (2) The enrichment of Pt, Pd and Au in black rock minerals not only shows the chalcophile affinity, but also shows obvious correlation with the geological conditions and geological setting of organic carbon formation. The results provide important information for studying the geochemical environment and the metallogenic regularity of the platinum group elements in black rocks.

Introduction Material and Methods Results Conclusions Evidence suggests that gestational diabetes mellitus (GDM) is associated with subsequent cardiovascular disease; however, it is unclear what impact changes in screening and diagnostic criteria have had on the association of GDM with long‐term outcomes such as cardiovascular disease. The purpose of this study was to determine the association between GDM and subsequent cardiovascular disease during a period of rising gestational diabetes diagnosis in England. Specifically, associations were compared before and after 2008, when national guidelines supporting risk factor‐based screening were introduced.We conducted a cohort study using routinely collected data from the Clinical Practice Research Datalink linked to the Hospital Episode Statistics and Office for National Statistics databases. The study consisted of persons aged 15–45 years with a livebirth or stillbirth between 1998 and 2017 and without a history of cardiovascular disease or pre‐pregnancy diabetes mellitus. Cox proportional hazards models, with propensity score weighting using matching weights, were used to estimate adjusted hazard ratios (aHRs) with 95% confidence intervals (CIs) for the association of GDM diagnosis in the first recorded pregnancy with subsequent cardiovascular disease.Among 232 315 individuals, the incidence of cardiovascular disease was 6.6 per 1000 person‐years among those with GDM and 2.2 per 1000 person‐years among those without GDM over a mean follow‐up duration of 5.8 years. The overall aHR, 95% CI was 1.91 (1.41, 2.60). Diagnosis of GDM increased over the study period, from 0.7% in 1998–99 to 5.3% in 2017. The effect size was not markedly different in the years before (1998–2007: adjusted HR 2.05, 95% CI 2.05 1.35, 3.12) and after 2008 (2008–2017: adjusted HR 1.79, 95% CI 1.15, 2.80).There was a strong association of GDM with cardiovascular disease after accounting for social and demographic factors and multiple comorbidities, and this association was present both before and after 2008, when national gestational diabetes screening criteria were established. [ABSTRACT FROM AUTHOR]

The prevalent new-user design includes a broader study population than the traditional new-user approach that is frequently used in pharmacoepidemiologic research. In an article appearing in this issue (Am J Epidemiol. 2021;190(7):1341–1348) , Webster-Clark et al. describe the treatment initiator types included in the prevalent new-user design and contrast the causal questions assessed using a prevalent new-user design versus a new-user design. They further applied a series of simulation studies showing the importance of accounting for treatment history in addition to time since initiation of the comparator in the prevalent new-user design. In this commentary, we put their findings in the broader context with a discussion of the strengths and limitations of the prevalent new-user design and settings where it would be most useful. The prevalent new-user design and new-user design both address unique questions of clinical and public health importance. Real-world evidence generated by pharmacoepidemiologic research is increasingly being used by regulators and other knowledge users to inform their decision-making. Understanding the causal questions addressed by different designs is crucial in this process; the study by Webster-Clark et al. represents an important step in addressing this issue. [ABSTRACT FROM AUTHOR]

Background: Due to improvements in imaging and radiological techniques as well as the use of chemotherapy, distant metastasis has become the predominant mode of treatment failure in patients with locally advanced nasopharyngeal carcinoma (LA-NPC). Platinum-based systemic chemotherapy has shown survival benefits and is now the standard strategy for systemic therapy in patients with LA-NPC. Notably, the third-generation platinum reagent lobaplatin has shown anti-tumor effects in several solid tumors with lower incidences of gastrointestinal, hepatic and renal toxicity relative to other platinum drugs. However, the safety and efficacy of lobaplatin as a first-line regimen in patients with LA-NPC are undetermined.Methods: Patients with stage III-IVa-b NPC received lobaplatin at a dose of 30 mg/m2 on days 1 and 22 combined with a continuous 120-h intravenous injection of 5-fluorouracil at a dose of 4 g/m2 followed by lobaplatin at a dose of 50 mg/m2 on days 43 and 64 concomitant with intensity-modulated radiation therapy. Objective response rates and acute toxicity were assessed based on RECIST (1.1) and CTCAE v.3.0, respectively. Kaplan-Meier analysis was used to calculate survival rates.Results: Fifty-nine patients were enrolled, and 44 patients (74.6%) received allocated cycles of chemotherapy. The objective response rates were 88.1% (95% confidence interval [CI], 0.77 to 0.95) and 100% after induction chemotherapy (ICT) and concurrent chemoradiotherapy (CRT), respectively. With a median follow-up period of 44 months, the 3-year estimated progression-free survival and overall survival were 86.4% (95% CI, 69.8 to 98.8) and 94.9% (95% CI, 89.5 to 100), respectively. The most common grade 3-4 toxicities were neutropenia (8.5%) and thrombocytopenia (40.7%) after ICT and CRT, respectively.Conclusion: Lobaplatin combined with 5-fluorouracil followed by lobaplatin-RT treatment showed encouraging anti-tumor effects with tolerable toxicities in patients with LA-NPC. Randomized controlled trials of lobaplatin in patients with LA-NPC are warranted.Trial Registration: This trial was registered with the Chinese Clinical Trials Registry and approved on March 31st, 2012, number ChiCTR-ONC-12002060 . [ABSTRACT FROM AUTHOR]

Accumulating evidence suggests a role for micro RNAs (mi RNAs) in regulating various processes of mammalian postnatal development and aging. To investigate the changes in blood-based mi RNA expression from preterm infants to adulthood, we compared 365 mi RNA expression profiles in a screening set of preterm infants and adults. Approximately one-third of the mi RNAs were constantly expressed from postnatal development to adulthood, another one-third were differentially expressed between preterm infants and adults, and the remaining one-third were not detectable in these two groups. Based on their expression in infants and adults, the mi RNAs were categorized into five classes, and six of the seven mi RNAs chosen from each class except one with age-constant expression were confirmed in a validation set containing infants, children, and adults. Comparing the chromosomal locations of the different mi RNA classes revealed two hot spots: the mi RNA cluster on 14q32.31 exhibited age-constant expression, and the one on 9q22.21 exhibited up-regulation in adults. Furthermore, six mi RNAs detectable in adults were down-regulated in older adults, and four chosen for individual quantification were verified in the validation set. Analysis of the network functions revealed that differentially regulated mi RNAs between infants and adults and mi RNAs that decreased during aging shared two network functions: inflammatory disease and inflammatory response. Four expression patterns existed in the 11 mi RNAs from infancy to adulthood, with a significant transition in ages 9-20 years. Our results provide an overview on the regulation pattern of blood mi RNAs throughout life and the possible biological functions performed by different classes of mi RNAs. [ABSTRACT FROM AUTHOR]

The article discusses a study which examined the relationship between incident obesity and stillbirth. The study involved women who became obese prior to a subsequent pregnancy. It analyzed the relationship between internal validity and external validity and the effect of pre-pregnancy obesity on the outcome of pregnancy.

Objective: Platinum-based chemotherapy in combination with radiotherapy is a standard treatment strategy for locoregionally advanced nasopharyngeal carcinoma (NPC). This study aimed to investigate the long-term efficacy and tolerability of inductive chemotherapy with docetaxel plus carboplatin (TC) or 5-fluorouracil plus carboplatin (FC) followed by concurrent radiation therapy in patients with NPC., Methods: Patients (N=88) were randomized to receive TC or FC as inductive therapy followed by concurrent radiotherapy (60-70 Gy) with two cycles of carboplatin (area under the curve =5 mg·h/L). Patients were followed up for 8 years. Primary end point was progression-free survival (PFS). Secondary end points included overall survival (OS), toxicity, tumor response, distant metastasis-free survival, and local recurrence-free survival., Results: At the end of the follow-up period, 31 patients died, 32 had disease progression, eleven had cancer recurrence, and 25 had distant metastasis. Overall, there was no difference between treatment groups with regard to response or survival. We found that following induction and concurrent chemoradiotherapy, the majority of patients showed a complete response (~96%-98% for induction therapy and 82%-84% for comprehensive therapy) to both therapies. PFS and OS were also similar between groups. The rate of PFS was 63.6% for both FC and TC and that of OS was 65.9% and 63.5%, respectively. The overall incidence of grade 3-4 adverse events in the TC group (20.5%) was higher than in the FC group (10.7%). Neutropenia and leukopenia were the most common grade 3-4 adverse events in the TC group, and mucositis was the most common in the FC group., Conclusion: These data indicate that TC and FC therapies have similar efficacy in treating locally advanced NPC and both are well tolerated.