[Evaluation of p16/Ki-67 double-stained immunohistochemistry in diagnosis of human papilloma virus-positive oropharyngeal squamous cell carcinoma].

Objective: To explore the diagnostic value of p16/Ki-67 double-stained immunohistochemistry in the diagnosis of human papilloma virus (HPV)-positive oropharyngeal squamous cell carcinoma(opscc) and find out the optimal index to improve the accuracy of HPV detection. Methods: A total of 153 cases, from May 2014 to May 2020, diagnosed OPSCC in Shanghai Ninth People's Hospital, Shanghai Jiao Tong University School of Medicine, were selected. This cohort included 130 males and 23 females, aged (58.6±10.0) years old. HPV RNA in situ hybridization was chosen as the gold standard to detect their HPV status. p16 immunohistochemistry and p16/Ki-67 double-stained immunohistochemistry were performed on all cases, and the p16/Ki-67 double positive index including 20%, 40%, and 60% were used as the thresholds to compare their sensitivity, specificity, and positive prediction value (PPV), negative prediction value (NPV) and prognosis prediction ability. Results: Among the 153 patients with OPSCC, 114 were HPV-negative and 39 were HPV-positive, and the HPV infection rate of OPSCC patients was 25.5% (39/153). Only 58.1% (36/62) of single p16 positive cases were HPV-positive, and the prognosis of patients could not be distinguished using p16 immunohistochemistry only. Using p16/Ki-67 double staining, the accuracy of HPV positive diagnosis has been improved. The HPV diagnostic ability was the highest when the p16/Ki-67 double positive index was 40% (sensitivity=86.8%, specificity=94.8%, PPV=84.6%, NPV=95.6%, area under the curve=0.897), which could distinguish the prognosis of patients (P=0.012). Conclusions: The p16/Ki-67 double-stained immunohistochemistry can improve the accuracy of HPV positive diagnosis rate and diagnosis of HPV-positive oropharyngeal cancer is the most accurate when the double-positive index is 40% as the threshold to judge HPV status and could serve as better surrogate marker for HPV detection.

[Establishment of patient-derived salivary gland basal cell adenoma organoids].

Objective: To establish an in vitro organoid model of human salivary gland basal cell adenoma (BCA). Methods: Fresh tumor sample from a 66-year-old female patient diagnosed with salivary gland BCA was collected from the Dpartment of Oral pathology, Ninth People's Hospital Affiliated to Shanghai Jiao Tong University School of Medicine in October 2021. And the organoid culture was performed in vitro in a culture medium based on solid droplets of matrix gel, and the growth of the organoid was observed by inverted microscopy. After 14 days, the organoid was fixed in 10% neutral formalin and made into paraffin blocks by agar pre-embedding paraffin embedding method, sectioned. HE staining, morphological observation and immunohistochemical staining of p63, Ki-67, cytokeratin14 (CK14), ß-catenin, S-100 and calponin were used for organoids identification. Results: The established BCA organoids were lobulated nodular locally under light microscopy, with deposition of eosinophilic glass-like material around the nests of organoid cells, similar to the morphological architectures of the parental BCA. Immunohistochemistry showed that organoids expressed CK14, p63, and ß-catenin in various degree, which was consistent with the immunophenotypic characteristics of the parental BCA tumor cells. Conclusions: An in vitro culture system of BCA organoids was preliminarily established which provides a new model for the study of the pathogenesis of salivary gland tumors.

Electrochemical and surface analyses of nanostructured Ti-24Nb-4Zr-8Sn alloys in simulated body solution.

The use of nanostructuring to improve the stability of passive thin films on biomaterials can enhance their effectiveness in corrosion resistance and reduce the release of ions. The thickness of the ultrathin films that cover Ti and Ti alloys (only several nanometers) has prevented researchers from establishing systematic methods for their characterization. This study employed a multifunctional biomedical titanium alloy Ti-24Nb-4Zr-8Sn (wt.%) as a model material. Coarse-grained (CG) and nanostructured (NS) alloys were analyzed in 0.9% NaCl solution at 37°C. To reveal the details of the passive film, a method of sample preparation producing a passive layer suitable for transmission electron microscope analysis was developed. Electrochemical corrosion behavior was evaluated by potentiodynamic polarization tests and Mott-Schottky measurements. Surface depth chemical profile and morphology evolution were performed by X-ray photoelectron spectroscopy and in situ atomic force microscopy, respectively. A mechanism was proposed on the basis of the point defect model to compare the corrosion resistance of the passive film on NS and CG alloys. Results showed that the protective amorphous film on NS alloy is thicker, denser and more homogeneous with fewer defects than that on CG alloy. The film on NS alloy contains more oxygen and corrosion-resistant elements (Ti and Nb), as well as their suboxides, compared with the film on CG alloy. These characteristics can be attributed to the rapid, uniform growth of the passive film facilitated by nanostructuring.

Combinations of three immunological assays for detecting anti-Toxoplasma IgG in the sera of patients infected with Toxoplasma gondii.

Enzyme-linked immunosorbent assay (ELISA), Dot-ELISA and Dot-immunogold silver staining (Dot-IGSS) were simultaneously used to detect the specific IgG against Toxoplasma gondii in 65 patients infected with the protozoa. The positive rates were 86.51%, 92.51% and 98.64%, respectively. When ELISA and Dot-ELISA results were put together, the positive rate increased to 95.38%. When Dot-IGSS results were combined with those of ELISA or Dot-ELISA, the positive rate was raised to 100%. The difference in positive rate between ELISA and Dot-IGSS was significant (x2 = 6.93, p < 0.01), but no statistically significant differences were found between ELISA and Dot-ELISA or between Dot-ELISA and Dot-IGSS. Paired comparison of the reacting intensities of the sera in the 3 assays showed the correlations were highly significant (p < 0.001), with r = 0.608 between Dot-IGSS and Dot-ELISA, r = 0.8194 between Dot-IGSS and ELISA and r = 0.517 between Dot-ELISA and ELISA. Hence combination of different serological assays may increase their sensitivity and specificity for detecting the anti-Toxoplasma antibodies.