Nocardia is a Gram-positive pathogen responsible for causing dairy mastitis,which leads to purulent granulomatous lesions in mammary tissue and can significantly impact the dairy indus-try,resulting in substantial economic losses.To develop a rapid and accurate diagnostic method for detecting Nocardia of bovine origin,a conserved sequence of the 16S rRNA gene from Nocardia was selected from the NCBI database.Based on this sequence,a pair of primers and a TaqMan fluo-rescent quantitative probe were designed.The validation of the TaqMan fluorescence quantitative PCR(qPCR)method found in this study showed that the Ctvalue had a good linear relationship with recombinant plasmid concentrations ranging from 1×1010 to 1×102 copies/μL,with a regres-sion equation of y=-3.536x+43.78,a correlation coefficient(R2)of 0.997 5,a slope of-3.536,and an amplification efficiency(E)of 91％(where 90％＜E＜110％).The specificity was strong,with no cross-reactions with other pathogens.The standard curve had a high sensitivity with a low-er detection limit of 1 × 102 copies/μL,it was 100-fold higher than conventional PCR.The repeatability of the standard curve was also good.Both intra-and inter-group coefficients of varia-tion were below 2％.Using this method,234 milk samples and 80 environmental samples were tested using this method,respectively,with a positive detection rate of 27.07％,whereas conven-tional PCR had a positive detection rate of 19.43％,indicating that this method was more sensitive compared to conventional PCR.The fluorescent quantitative PCR detection method established in this study provides an effective means for the clinical detection of Nocardia in dairy cows.

Nocardia is a Gram-positive pathogen responsible for causing dairy mastitis,which leads to purulent granulomatous lesions in mammary tissue and can significantly impact the dairy indus-try,resulting in substantial economic losses.To develop a rapid and accurate diagnostic method for detecting Nocardia of bovine origin,a conserved sequence of the 16S rRNA gene from Nocardia was selected from the NCBI database.Based on this sequence,a pair of primers and a TaqMan fluo-rescent quantitative probe were designed.The validation of the TaqMan fluorescence quantitative PCR(qPCR)method found in this study showed that the Ctvalue had a good linear relationship with recombinant plasmid concentrations ranging from 1×1010 to 1×102 copies/μL,with a regres-sion equation of y=-3.536x+43.78,a correlation coefficient(R2)of 0.997 5,a slope of-3.536,and an amplification efficiency(E)of 91％(where 90％＜E＜110％).The specificity was strong,with no cross-reactions with other pathogens.The standard curve had a high sensitivity with a low-er detection limit of 1 × 102 copies/μL,it was 100-fold higher than conventional PCR.The repeatability of the standard curve was also good.Both intra-and inter-group coefficients of varia-tion were below 2％.Using this method,234 milk samples and 80 environmental samples were tested using this method,respectively,with a positive detection rate of 27.07％,whereas conven-tional PCR had a positive detection rate of 19.43％,indicating that this method was more sensitive compared to conventional PCR.The fluorescent quantitative PCR detection method established in this study provides an effective means for the clinical detection of Nocardia in dairy cows.

BACKGROUND: Segmentectomy can retains more healthy lung tissue than lobectomy, but it remains controversial in oncology for early stage lung cancer. The aim of this study is to discuss the problems of video-assisted thoracic surgery (VATS) segmentectomy in early stage lung cancer, by analyzing the clinical and pathological data of 35 cases and reviewing the literature. METHODS: There were 35 patients who received segmentectomy by complete video-assisted thoracic surgery, from May 2013 to July 2017, in single operation group in the Third Hospital of Peking University. We analyzed the patient's clinical and pathological data, intraoperative and postoperative complications, lymph node number and metastasis its situation, and compared postoperative pathology and preoperative computed tomography (CT) imaging type. In 35 cases of segmentectomy, there were 11 males and 24 females, with an average age of 57.7 years old. The lesions located in the right upper lobe were 8 cases, in the right lower lobe were 8 cases, in the left upper lobe were 13 cases, in the left lower lobe were 6 cases. The mean maximum diameter of CT imaging was 12.7 mm, and the largest diameter of hilar and mediastinal lymph nodes was less than 10 mm. 23 of them were ground glass predominating and 12 were solid components predominating. RESULTS: All 35 cases were successfully completed VATS anatomical segmentectomy. The average operation time was 153 minutes, the amount of bleeding was 51 mL. There were 10 cases of air leakage after operation, all of which were not more than 3 days. There was contralateral atelectasis in 1 case, chylothorax in 1 case. The average length of hospitalization was 6.1 days. There was no other complications outpatient related to surgery, in 30 days after discharge. The pathological changes were as follow, 2 cases of metastatic tumor, 8 cases of benign lung disease and 25 cases of primary lung cancer. In the 25 cases of primary lung cancer, there were 14 cases of invasive lung adenocarcinoma (7 cases were groundglassopacity (GGO) predominating in CT imaging), 4 cases of micro-invasive adenocarcinoma (3 cases were GGO predominating in CT imaging), 6 cases of adenocarcinoma in situ (all were pure GGO in CT imaging), 1 case of lung squamous cell carcinoma (mainly composed of solid in CT imaging). An average of 7.2 lymph nodes were removed in 25 cases of lung cancer, and all lymph nodes had no metastasis. CONCLUSIONS VATS anatomical segmentectomy is technically safe and reliable, and the indications for lung cancer need to be strictly controlled. Its advantages still need to be confirmed by prospective randomized controlled trials.
Female ; Humans ; Lung Neoplasms ; pathology ; surgery ; Male ; Middle Aged ; Neoplasm Staging ; Retrospective Studies ; Thoracic Surgery, Video-Assisted ; adverse effects ; methods

Background and objective hTe development of image technology has led to increasing detection of pulmonary small nodules year by year, but the determination of their nature before operation is diffcult. hTis clinical study aimed to investigate the necessity and feasibility of surgical resection of pulmonary small nodules through a minimally invasive approach and the operational manner of non-small cell lung cancer (NSCLC). Methods hTe clinical data of 129 cases with pulmonary small nodule of 10 mm or less in diameter were retrospectively analyzed in our hospital from December 2013 to November 2016. hTin-section computed tomography (CT) was performed on all cases with 129 pulmonary small nodules. CT-guided hook-wire precise localization was performed on 21 cases. Lobectomy, wedge resection, and segmentectomy with lymph node dissection might be performed in patients according to physical condition. Results Results of the pathological examination of 37 solid pulmonary nodules (SPNs) revealed 3 primary squamous cell lung cancers, 3 invasive adenocarcino-mas (IAs), 2 metastatic cancers, 2 small cell lung cancers (SCLCs), 16 hamartomas, and 12 nonspeciifc chronic inlfammations. hTe results of pathological examination of 49 mixed ground glass opacities revealed 19 IAs, 6 micro invasive adenocarcinomas (MIAs), 4 adenocarcinomas in situ (AIS), 1 atypical adenomatous hyperplasia (AAH), 1 SCLC, and 18 nonspeciifc chronic in-lfammations. hTe results of pathological examination of 43 pure ground glass opacities revealed 19 AIS, 6 MIAs, 6 IA, 6 AAHs, and 6 nonspeciifc chronic inlfammations. Wedge resection under video-assisted thoracoscopic surgery (VATS) was performed in patients with 52 benign pulmonary small nodules. Lobectomy and systematic lymph node dissection under VATS were performed in 33 patients with NSCLC. Segmentectomy with selective lymph node dissection, wedge resection, and selective lymph node dissection under VATS were performed in six patients with NSCLC. Two patients received secondary lobectomy and systematic lymph node dissection under VATS because of intraoperative frozen pathologic error that happened in six cases. Two cases of N2 lymph node metastasis were found in patients with SPN of IA. Conclusion Positive surgical treatment should be taken on patients with persistent pulmonary small nodules, especially ground glass opacity, because they have a high rate of malignant lesions. During the perioperative period, surgeons should fully inform the patients and family members that error exist in frozen pathologic results to avoid medical disputes.