[Clinicopathological analysis of nuclear protein in testis midline carcinoma].

Objective: To investigate the clinicopathological features, immunophenotype and prognosis of nuclear protein in testis (NUT) midline carcinoma. Methods: Twenty-four resection cases of NUT midline carcinoma diagnosed at the Department of Pathology, Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, China from January 2018 to September 2022, were collected, and retrospectively analyzed for their clinicopathological characteristics. Relevant literature was reviewed. Results: All 24 cases of NUT midline carcinoma occurred in the chest or head and neck, including 14 men and 10 women, with a median age of 40 years. Histological examination showed that the tumors were poorly differentiated, with solid nested or sheet-like arrangement, small to medium-sized cells, sparse cytoplasm and coarse granular chromatin, including 5 cases with abrupt squamous epithelial differentiation. Immunohistochemistry showed that all 24 cases were positive for NUT protein, while 16 cases were p63 positive, 19 cases were p40 positive, 15 out of 18 cases were CK5/6 positive. Follow-up data were obtained for 21 patients (follow-up time range, 1-21 months), of which 11 survived, 10 died, and 3 were lost to follow-up. Conclusions: NUT midline carcinoma is a rare and highly aggressive malignancy with unique histological, immunophenotypic and molecular features. It has a poor prognosis.

Rapid Determination of Ammonia in Biological Samples by GC-MS Derivatization Method.

ABSTRACT: Objective To establish a qualitative and quantitative method to determine ammonia in biological samples by gas chromatography-mass spectrometry （GC-MS）. Methods A heptafluorobutyryl chloride derivatization method was used. GC-MS was used for determination. The effects of different pH conditions, derivatization temperature, time and different extraction solvents on the test results were investigated. The pretreatment conditions were optimized. Results This method could accurately detect the ammonia content in blood, and the limit of detection was determined to be 0.1 µg/mL. The target component showed good linearity in the range of 0.5-200.0 µg/mL （R2=0.987 7）. The relative standard deviation range of intra-day precision was 2.59%-3.88%. The relative standard deviation range of inter-day precision was 3.21%-3.76%. Conclusion The method showed good sensitivity, stability and specificity, therefore can be used for forensic toxicology analysis and clinical biochemical detection.

[Research Progress on Estimation of Postmortem Submersion Interval].

ABSTRACT: Postmortem interval （PMI） estimation is one of the most important and difficult academic tasks in forensic sciences. Due to the influence of the corpse itself and the water environment, corpses in water have unique corruption phenomenon and laws. Based on the experience of traditional PMI studies of corpses on land, forensic practitioners across the world have proposed a variety of practical methods for estimating postmortem submersion interval （PMSI）. This paper summarizes the literatures related to PMSI in recent years, and introduces methods to infer PMSI according to the phenomenon of corpses, the development of insects, the succession pattern of aquatic organisms, and the changes of other physical and chemical indexes of corpses, in order to provide some reference for the study of PMSI of corpses in water.

[The preliminary report of a registration clinical trial of proton and heavy ion irradiation].

Objective: To verify the safety and efficacy of IONTRIS particle therapy system (IONTRIS) in clinical implementation. Methods: Between 6.2014 and 8.2014, a total of 35 patients were enrolled into this trial: 31 males and 4 females with a median age of 69 yrs (range 39-80). Ten patients had locally recurrent head and neck tumors after surgery, 4 cases with thoracic malignancies, 1 case with hepatocellular carcinoma, 1 case with retroperitoneal sarcoma, and 19 cases with non-metastatic prostate carcinomas. Phantom dose verification was mandatory for each field before the start of radiation. Results: Twenty-two patients received carbon ion and 13 had proton irradiation. With a median follow-up time of 1 year, all patients were alive. Among the 16 patients with head and neck, thoracic, and abdominal/pelvic tumors, 2, 1, 12, and 1 cases developed complete response, partial response, stable disease, or disease progression, respectively. Progression-free survival rate was 93.8% (15/16). Among the 19 patients with prostate cancer, biological-recurrence free survival was 100%. Particle therapy was well tolerated in all 35 patients. Twenty-five patients (71.4%) experienced 33 grade 1 acute adverse effects, which subsided at 1 year follow-up. Six (17.1%) patients developed grade 1 late adverse effects. No significant change in ECOG or body weight was observed. Conclusions: IONTRIS is safe and effective for clinical use. However, long term follow-up is needed to observe the late toxicity and long term result.

Isolation, identification and characterization of lignin-degrading bacteria from Qinling, China.

AIMS: Lignin is an aromatic heteropolymer forming a physical barrier and it is a big challenge in biomass utilization. This paper first investigated lignin-degradation bacteria from rotten wood in Qinling Mountain. METHODS AND RESULTS: Nineteen potential strains were selected and ligninolytic enzyme activities were determined over 84 h. Strains that had higher enzyme activities were selected. Further, the biodegradation of wheat straw lignin and alkali lignin was evaluated indicating that Burkholderia sp. H1 had the highest capability. It was confirmed by gel permeation chromatography and field emission scanning electron microscope that alkali lignin was depolymerized into small fragments. The degraded products were analysed using gas chromatography-mass spectrometry. The total ion chromatograph of products treated for 7 days showed the formation of aromatic compounds, an important intermediate from lignin degradation. Interestingly, they disappeared in 15 days while the aldehyde and ester compounds increased. CONCLUSIONS: The results suggest that the lignin-degrading bacteria are abundant in rotten wood and strain H1 has high potential to break down lignin. SIGNIFICANCE AND IMPACT OF THE STUDY: The diversity of lignin-degrading bacteria in Qinling Mountain is revealed. The study of Burkholderia sp. H1 expands the range of bacteria for lignin degradation and provides novel bacteria for application to lignocellulosic biomass.

[Determination of 1-methylhydantoin Concentration in Blood by GC-MS Method and Its Application in Forensic Medicine].

OBJECTIVES: To establish a gas chromatographic-mass spectrometric （GC-MS） analysis method for quantifying 1-methylhydantoin concentration in whole blood. To provide technical support to forensic identification related cases of 1-methylhydantoin. METHODS: As an internal standard, 500 ng SKF525A was added to 0.5 mL blood sample, and then 2 mL 0.01 mol/L dilute hydrochloric acid and 0.5 g ammonium carbonate were added in order to buffer the pH value to 9, and following 2 mL ethyl acetate. The organic solvent layer was obtained after centrifuge and then analysed by GC-MS after drying. RESULTS: Good linear relationship of 1-methylhydantoin in blood was obtained in the range of 0.5-50 ng/mL. The equation of linear regression was y=0.015 51 x+0.007 26（R²=0.999 7） with 0.1 ng/mL detection limit, and the recovery was 93.02%-108.12%. The intra-day and inter-day precision were less than 6.07% and 13.37%, respectively. CONCLUSIONS: The results gotten by this method is accurate and reproducible, which can be used for the determination of 1-methylhydantoin concentration in blood samples.

Data evaluations and quantitative predictive models for vapor pressures of polycyclic aromatic hydrocarbons at different temperatures.

Polycyclic aromatic hydrocarbons (PAHs) are typical and ubiquitous organic pollutants. Vapor pressures, which can be classified as solid vapor pressure (P(S)) and (subcooled) liquid vapor pressure (P(L)), are key physicochemical properties governing the environmental fate of organic pollutants. It is of great importance to develop predictive models of vapor pressures. In the present study, partial least squares (PLS) regression together with 15 theoretical molecular structural descriptors was used to develop quantitative predictive models for vapor pressures of PAHs at different temperatures. Two procedures were adopted to develop the optimal predictive models by eliminating redundant molecular structural descriptors. The cross-validated Q2(cum) values for the obtained models have been found higher than 0.975, indicating good predictive ability and robustness of the models. It has been shown that the intermolecular dispersive interactions played a leading role in governing the values of log P(L). In addition to dispersive interactions, dipole-dipole interactions also played a secondary role in determining the magnitude of log P(S). In view of the scarceness of chemical standards for some PAHs, the difficulty in experimental determinations, and the high cost involved in experimental determinations, the obtained models should serve as a fast and simple first approximation of the vapor pressure values for PAHs at different environmental temperatures.