Acute mediastinitis associated with tracheobronchial tuberculosis and aspergillosis: a case report and literature review

Acute mediastinitis (AM) is a rare but life-threatening disease. Here, we report a case of AM secondary to endobronchial tuberculosis (EBTB) and pseudomembranous Aspergillus tracheobronchitis (PMATB) co-infection. EBTB was confirmed by tissue culture for Mycobacterium tuberculosis and GeneXpert MTB/RIF (Cepheid, Sunnyvale, CA, USA) detection (simultaneous detection of M. tuberculosis and resistance to rifampin) using endobronchial biopsies; PMATB was confirmed by histopathology. Even with antibiotic treatment and systemic support treatment, the patient died of massive hemoptysis on day 10 after admission. When immunocompromised hosts have AM, especially with central airway involvement, EBTB and aspergillosis should be considered potential causes. Bronchoscopy is helpful for rapid diagnosis and administering precise treatment.

Malignant Transformation of a Borderline Ovarian Tumor With Pulmonary and Pleural Metastases After Years of Latency: A Case Report and Literature Review

Borderline ovarian tumor (BOT) refers to a distinct tumor of the ovary of epithelial origin and typically has a favorable prognosis. However, these tumors are not exempt from risks of recurrence and malignant transformation, which can arise from the remaining ovarian tissue, peritoneal implants, or distant localization. Here, we report a case of a mucinous BOT with multiple pulmonary cystic nodules without evidence of pulmonary metastasis even after two fine needle biopsies. Staging surgery was performed, and no evidence of peritoneal implants or invasion to adjacent organs found. At the end of the 7-year monitored follow-up after surgery, the pulmonary lesions were found to be increased in size. The transbronchial lung biopsy and pleural biopsy confirmed transformation into malignant mucinous adenocarcinoma with pleural metastasis. In the current case, we observed potential pulmonary metastasis of the BOT with malignant transformation and a latency as long as 7 years, which reminds us that multiple pulmonary cystic changes in patients with BOTs should be screened carefully to evaluate the pulmonary involvement of BOTs and potentially false-negative results after fine needle biopsy. Thus, a thorough check-up for complete staging of the disease and a close long-term follow-up to monitor potential recurrence and malignant transformation are advised.

Large Tracheocutaneous Fistula Successfully Treated With Bronchoscopic Intervention and Flap Grafting: A Case Report and Literature Review

Tracheocutaneous fistula (TCF) is the most common related post-operative complication after tracheotomy. Treatments such as surgery and flap grafting are usually applied to close TCFs. We report a case of a large TCF with an area of ~3.0 cm × 1.0 cm. Here, we describe a relatively convenient approach for the management of a patient with a large TCF. In our treatment strategy, a coverd tracheal stent was used to cover the defect by bronchoscopy, the bronchial defect was closed with a local turnover flap, the structure was reinforced with biodegradable material (RapidSorb Plate 2.0), and then transplantation of a deltopectoral flap was performed. It is worth noting that the patency of the trachea was maintained during the whole surgery course. No recurrence or complications occurred after the 12-month follow-up. The large TCF was successfully treated with bronchoscopic intervention, biodegradable material and flap grafting, and without cartilage grafting.

Endobronchial Valves for the Treatment of Bronchopleural Fistula and Pneumothorax Caused by Pulmonary Cryptococcosis in an AIDS Patient

Cryptococcal disease is an opportunistic infection that occurs primarily among people with advanced HIV disease and is an important cause of morbidity and mortality. Spontaneous pneumothorax (SP) is rare in acquired immune deficiency syndrome (AIDS) patients with pulmonary cryptococcosis (PC), but when it occurs, rapid and effective treatment is crucial to the prognosis, with mortality rates varying from 30 to 60%. SP is related to pneumonia mainly due to bacterial infections and pneumocystic jirovecii pneumonia (PJP). However, SP caused by PC is rare. When it occurs, it is often fatal and refractory, which is a challenge both for patients and clinicians. Here, we report a case of SP during the treatment of cryptococcal disease in a patient with AIDS. The pneumothorax remained despite chest tube drainage and evolved into a bronchopleural fistula that was confirmed by the Chartis system. The pneumothorax was significantly resolved following the placement of 2 endobronchial valves (EBVs). The patient tolerated the procedure very well and the pneumothorax gradually resolved. When immunocompromised patients suffer from refractory pneumothorax or prolonged air leaks, EBV implantation may be a feasible and minimally invasive procedure for this vulnerable population.

Multiple extramedullary plasmacytomas of the trachea and pharyngeal tissue: a case report and literature review

Extramedullary plasmacytoma (EMP) is an infrequent form of plasma cell dyscrasia that presents as a mass of monoclonal plasma cells located in extramedullary soft tissues with no skeletal component. EMP constitutes ~4% of all plasma cell neoplasms and occurs mostly in the upper respiratory tract. Here, we report a rare case of multiple EMPs involving the trachea, laryngopharynx, and oropharynx, which caused symptoms of airway obstruction as the only clinical manifestation. The patient was diagnosed by histopathology of the tissue from bronchoscopic resection and successfully managed with bronchoscopic intervention to treat lesions in the trachea and radiotherapy combined with surgical resection to treat lesions in the pharynx. There was no recurrence after 14 months of follow-up. Endoscopic intervention plays a key role in the rapid diagnosis and treatment of EMP involving the central airways.

Association of genetic variations in the ACLY gene with growth traits in Chinese beef cattle

ATP citrate lyase (ACLY) is the primary enzyme responsible for the synthesis of cytosolic acetyl-CoA, which is a key precursor of both fatty acid and mevalonate synthesis pathways. Genetic variation of the ACLY gene may influence multiple traits associated with animal production. Here, we identified three non-synonymous mutations in ACLY exons in five beef cattle populations using DNA pool sequencing and high-resolution melting analysis. Results from association analyses revealed that the single nucleotide polymorphism (SNP) g.17127C>T is significantly associated with chest girth (P < 0.01) and body height (P < 0.05) in the Fleckvieh x Zhangye local crossbred cattle, and with body slanting length (P < 0.05) in the Simmental x Guyuan local crossbred cattle. SNP g.40427T>C is significantly associated with an increase in chest girth (P < 0.05) in the Simmental x Huzhu cattle population. These results provide preliminary evidence that polymorphisms in the bovine ACLY gene are associated with growth traits in beef cattle in northwest China. However, a larger sample set is needed to validate these findings.

Association between single-nucleotide polymorphisms of fatty acid synthase gene and meat quality traits in Datong Yak (Bos grunniens)

Fatty acid synthase (FASN) is a key enzyme in fatty acid anabolism that plays an important role in the fat deposit of eukaryotic cells. Therefore, in this study, we detected 2 novel single-nucleotide polymorphisms (SNPs) in the FASN gene in 313 adult individuals of Datong yak using polymerase chain reaction-single strand conformation polymorphism and DNA sequencing techniques. SNP g.5477C>T is located in intron 3 of FASN, and 3 genotypes, HH, HG, and GG, were detected in this mutation site. SNP g.16930T>A is located in exon 37 of FASN, and 2 genotypes, EE and EF, were detected in this site. Association analysis of these 2 SNPs with meat quality traits showed that in SNP g.5477C>T, yaks with the HH genotype and HG genotype had significantly higher intramuscular fat content than individuals with the GG genotype (P < 0.01). In SNP g.16930T>A, yaks with the EE genotype also had significantly higher IMF content than individuals with the EF genotype (P < 0.01). The results indicate that FASN may be used as a candidate gene affecting intramuscular fat content in Datong yaks.

Association of novel single-nucleotide polymorphisms of the vascular endothelial growth factor-A gene with high-altitude adaptation in yak (Bos grunniens)

Vascular endothelial growth factor-A gene (VEGF-A) is a key regulator of angiogenesis and an endothelial cell mitogen that plays an important role in high-altitude adaptation. In this study, we detected 2 novel single-nucleotide polymorphisms (SNPs) of VEGF-A by screening for genetic variation in 700 individuals of 3 domestic Chinese yak breeds--namely Gannan (GN), Datong (DT), and Tianzhu white (TZW)--using polymerase chain reaction-restriction fragment length polymorphism and DNA sequencing techniques. GN and DT yaks live at high altitude and TZW yaks live at low altitude on the Qinghai-Tibetan Plateau. SNP g.8430T>C is located in intron 4 of VEGF-A. SNP g.14853G>A is located in the 3' untranslated region of VEGF-A. Frequencies of the GA and AA genotypes and the A allele of SNP g.14853G>A observed in GN and DT yaks were significantly higher than that in TZW yaks (P < 0.01). No significant difference among the breeds was observed for SNP g.8430T>C. The frequency of haplotype TA was significantly higher (P < 0.01), whereas the frequency of TG (P < 0.01) was significantly lower in GN and DT yaks compared with that in TZW yaks. The 2 SNPs were in moderate linkage disequilibrium in GN and DT yaks, but not in TZW yaks. The fixation index (FST) pairwise value was significantly different among the breeds studied. The neutral test result indicated that the region between the 2 SNPs may have been subjected to positive or balancing selection, and the high-altitude hypoxia environment might be the main determinant for selection. These results suggest that VEGF-A might contribute to the high-altitude adaptability of yak.

Associations of single nucleotide polymorphisms in candidate genes with the polled trait in Datong domestic yaks

The domestic yak (Bos grunniens) is an iconic symbol of animal husbandry at high altitudes. Yaks exhibit unique external characteristics including long hair and large horns. However, hornless yaks can be found in different breeds and different populations. The hornless trait is also known as polled, and the POLL locus has been fine-mapped to chromosome 1 in cattle (Bos taurus), although the underlying genetic basis of the polled trait is still unclear in the yak. Thus, we performed an association study to identify the genetic polymorphisms responsible for the polled trait in the yak. Fifty polled Datong domestic yaks and 51 horned individuals were selected randomly from a huge herd and were used as the case and control groups respectively for the association analysis. Twelve genes located in the candidate region of the POLL locus in cattle were used as references to detect DNA polymorphisms related to yak polledness, which were analyzed by sequencing and a high-resolution melting test. We applied Fisher's exact test and haplotype analysis to show that a 147-kb segment that included three protein-coding genes C1H21orf62, GCFC1 and SYNJ1 was the most likely location of the POLL mutation in domestic yaks.

Roles of gamma-Globulin in the Dynamic Interfacial Behavior of Mixed Dipalmitoyl Phosphatidylcholine/gamma-Globulin Monolayers at Air/Liquid Interfaces

This study investigated the roles of gamma-globulin in the dynamic interfacial behavior of dipalmitoyl phosphatidylcholine (DPPC)/gamma-globulin monolayers at air/liquid interfaces at 25 degrees C. The surface tension behavior demonstrated that gamma-globulin had a large adsorption time scale. Moreover, the surface pressure-area hysteresis behavior of adsorbed gamma-globulin monolayers suggested that no significant desorption occurred during the compression stage, and the respreading of gamma-globulin molecules at the interface during the expansion stage was slow. From the hysteresis behavior of adsorbed gamma-globulin monolayers with spread DPPC molecules, it was found that gamma-globulin molecules were expelled from the interface as DPPC molecules were in a condensed state. The squeeze-out of gamma-globulin molecules seemed to induce the loss of DPPC molecules at the interface with the extent depending on the initial gamma-globulin surface concentration. Furthermore, the expelled gamma-globulin molecules re-entered the monolayer and participated in the surface pressure increase during the following expansion stage. The exclusion of gamma-globulin associated with the removal of DPPC during monolayer compression and the re-entry of gamma-globulin during subsequent monolayer expansion represented a mechanism for DPPC depletion and gamma-globulin enrichment at the interface, which may explain the inhibitory effect of certain proteins on the surface activity of DPPC. Copyright 2000 Academic Press.