A method with ultra-high angular resolution for X-ray diffraction experiments.

In X-ray diffraction measurements, the angular resolution has a detection limit due to the receiving size of the detector. In many cases this detection limit is too large and must be breached to obtain the desired information. A novel method is proposed here by making the detector simultaneously measuring and moving. Using the deconvolution algorithm to remove the convolution effect, the pixel size limitation is finally broken. The algorithm used is not a common one, and suppresses signals at high frequencies, ensuring the reliability of the peak shape after restoration. The feasibility of this method is verified by successfully measuring the crystal truncation rod signal of SrTiO3 single crystal, and the resolution is nearly ten times higher than that of a single pixel. Moreover, this method greatly reduces the noise and improves the signal-to-noise ratio.

[Application of PRAME immunohistochemistry in the differential diagnosis of primary endometrial and endocervical adenocarcinomas].

Objective: To investigate the diagnostic value of preferentially expressed antigen in melanoma (PRAME) immunohistochemical staining in differential diagnosis of primary endometrial and endocervical adenocarcinomas. Methods: Eighty-seven cases of endometrial adenocarcinoma and sixty-three cases of cervical adenocarcinoma were collected from May 2018 to November 2023 in the Department of Pathology, Nanjing Drum Tower Hospital, the Affiliated Hospital of Nanjing University Medical School and all the cases were subject to PRAME immunohistochemical staining. The difference of PRAME expression between endometrial and endocervical adenocarcinomas was analyzed. Results: In 87 cases of endometrial adenocarcinoma, patients' age ranged from 35 to 71 years (average 59 years, median 59 years); in 63 cases of cervical adenocarcinoma patients' age ranged from 28 to 80 years (average 49 years, median 47 years). Seventy-eight cases (78/87, 89.7%) of endometrial adenocarcinoma; 2 cases (2/63, 3.2%) of cervical adenocarcinoma showed positive PRAME staining, and both cases of cervical adenocarcinoma were clear cell carcinoma. The sensitivity and specificity of PRAME in distinguishing between endometrial and cervical adenocarcinoma in the cohort were 89.7% and 96.8%, while those in differentiating non-clear cell carcinoma of the uterus from that of the cervix reached up to 91% and 100%, respectively. Conclusions: Immunohistochemical staining for PRAME demonstrates statistically significant differences between endometrial and cervical carcinomas, making it a useful auxiliary diagnostic marker for differentiating cervical and endometrial adenocarcinoma, especially non-clear cell carcinoma.

[Pathological features and diagnostic significance of lung biopsy in occupational lung diseases].

Objective: To investigate the clinicopathological characteristics of occupational lung diseases, to reduce the missed diagnoses and misdiagnoses of the diseases and to help standardize the diagnosis and treatment of these patients. Methods: A total of 4 813 lung biopsy specimens (including 1 935 consultation cases) collected at the Department of Pathology, Nanjing Drum Tower Hospital, Nanjing, China from January 1st, 2017 to December 31th, 2019 were retrospectively analyzed. Among them, 126 cases of occupational lung diseases were confirmed with clinical-radiological-pathological diagnosis. Special staining, PCR and scanning electron microscopy were also used to rule out the major differential diagnoses. Results: The 126 patients with occupational lung diseases included 102 males and 24 females. All of them had a history of exposure to occupational risk factor(s). Morphologically, 68.3% (86/126) of the cases mainly showed pulmonary fibrotic nodules, dust plaque formation or carbon end deposition in pulmonary parenchyma. 16.7% (21/126) of the cases mainly showed welding smoke particle deposition in the alveolar cavity and lung interstitium while 15.1% (19/126) of the cases showed granulomas with fibrous tissue hyperplasia, alveolar protein deposition or giant cell interstitial pneumonia. The qualitative and semi-quantitative analyses of residual dust components in the lung under scanning electron microscope were helpful for the diagnosis of welder's pneumoconiosis and hard metal lung disease. Conclusions: The morphological characteristics of lung biopsy tissue are important reference basis for the clinicopathological diagnosis and differential diagnosis of occupational lung diseases. Recognizing the characteristic morphology and proper use of auxiliary examination are the key to an accurate diagnosis of occupational lung diseases on biopsy specimens.

Surfactin inhibits the growth of Propionibacterium acnes by destroying the cell wall and membrane.

Propionibacterium acnes plays a major role in acne vulgaris. In the pre-experiment, the growth of P. acnes was inhibited effectively using surfactin; however, the antibacterial mechanism has not been described. Therefore, the aim of this study was to evaluate antibacterial activity and analyse the mechanism of surfactin against P. acnes. Minimum inhibitory concentration, time-killing kinetics and scanning electron microscopy were used to evaluate the activity of surfactin against P. acnes, which showed that 128 µg ml-1 effectively inhibited growth. Cell wall permeability was evaluated by detecting the extracellular alkaline phosphatase activity, which increased to 1·83- and 2·32-fold after incubating with 128 and 256 µg ml-1 of surfactin for 10 h, respectively. Propidium iodide fluorescence, leakage of nucleic acid, protein, K+ , and Ca2+ , membrane potential and the leakage of calcein from small unilamellar vesicles all increased after incubation with surfactin, indicating that its strong biological activities act mainly by altering membrane integrity. In a mouse model of acne, surfactin significantly reduced P. acnes-induced epidermal swelling and erythema. These results indicate that surfactin effectively inhibited the growth of P. acnes by destroying the cell wall and membrane, and is a potential candidate for acne treatment.

[Application of preventive flap-placement of terminal ileostomy in laparoscopic radical resection of low rectal cancer].

Objective: To evaluate the value of preventive flap placement of terminal ileostomy in laparoscopic radical resection of low rectal cancer. Methods: A retrospective analysis was conducted in the patients (n=63) who received preventive terminal ileostomy in laparoscopic radical resection of low rectal cancer in our institution from April 2016 to March 2018, including 33 patients who underwent ileostomy with flap-placement (flap group), and 30 patients who underwent ileostomy with stent (stent group). Clinical data were collected from both groups and statistically analyzed. Results: All patients were successfully completed laparoscopic radical resection with preventive ileostomy. All patients of stent group received stoma-closure surgery one month later after rectal resection. There were significantly statistical differences in operating time of ileostomy (28.9±4.3 vs 36.3±2.3, t=11.73, P<0.001) and overall stoma-related complications (1 vs 7, χ(2)=4.155, P=0.042), but no difference in anastomosis leakage, operating time of stoma-reversal, parastomal infection, parastomal hernia and parastomal prolapse. Conclusions: Preventive flap placement of terminal ileostomy represents a secure and feasible approach to laparoscopic low rectal cancer resection. Patients can be released from the discomfort of removing the stent and may suffer fewer stoma-related complications.

[Myofibroma/myofibromatosis: a clinicopathologic analysis of 9 cases].

Objective: To investigate the clinical and histological features, diagnosis and differential diagnosis of myofibroma/myofibromatosis. Methods: The clinical data and pathology features of nine cases of myofibroma/myofibromatosis were collected from August 2011 to November 2016 in Affiliated Drum Tower Hospital, Nanjing University Medical School and Children's Hospital of Nanjing Medical University. Immunohistochemistry(IHC), PDGFRB molecular analysis and ETV6-NTRK3 gene fusion were performed and relevant literature reviewed. Results: There were 7 males and 2 females, with age ranging from 3 days to 18 years (mean 5 years). The tumors were located in head and neck (eight cases) and trunk (one case). Clinically, the tumors presented as freely movable nodules. Microscopically, they appeared biphasic with alternating light- and dark-staining areas. The light-staining area consisted mainly of plump myoid spindle cells with eosinophilic cytoplasm arranged in nodules, short fascicles, or whorls.The dark-staining area was composed of round or polygonal cells with slightly hyperchromatic nuclei or small spindle cells arranged around a distinct hemangiopericytoma-like vascular pattern. IHC showed the tumor cells in the light-staining area were strongly positive for vimentin and SMA, while cells in dark-staining area were strongly positive for vimentin, and weakly for SMA. Tumor cells were negative for desmin, S-100 protein, h-Caldesmon, CD34 and STAT6. Analysis of PDGFRB mutations was performed in seven cases. Two cases showed 12 exon point mutation c. 1681 c>T(p.R561C), one case showed 14 exon point mutation c. 1998C>G (p.N666K). ETV6-NTRK3 gene fusion was not detected by fluorescence in situ hybridization in four patients under three years old. All cases were followed for 6 to 68 months, with two recurrences. Conclusions: Myofibroma/myofibromatosis is an uncommon benign myofibroblastic tumor of infancy and childhood. The tumor can appear biphasic, and may show PDGFRB point mutation which is of potential diagnostic value.