Pulmonary cyst newly formed after lobectomy in various underlying lung conditions.

BACKGROUND: It has been recently recognized that pulmonary cyst may develop after pulmonary resection, causing various symptoms. Most previously reported cases were after upper lobectomy in patients with chronic obstructive lung disease (COPD). CASE PRESENTATION: Case 1 was a man in his 70 s with interstitial pneumonia (IP). Right lower lobectomy was performed for metastatic lung tumor using video-assisted thoracoscopic surgery (VATS). On postoperative day (POD) 19, computed tomography (CT) revealed a large cyst at the upper interlobular surface of the middle lobe, with pneumoderma and pneumomediastinum. The cyst was incised, polyglycolic acid (PGA) sheet and fibrin glue were applied, and the cyst was sutured. The sutured line was covered again with PGA sheet and fibrin glue. Case 2 was a man in his 70 s with COPD. Right upper lobectomy for primary lung cancer was performed using VATS. On POD 17, CT revealed a large pulmonary cyst at the apex of S6 and massive air leakage was observed. The same surgical procedure as that used in case 1 was performed. Cases 3 and 4 were healthy donors for living-donor lung transplantation. Two months after the right lower lobectomy in Case 3 and 3 months after the left lower lobectomy in Case 4, the patients had respiratory symptoms such as dyspnea and hemosputum. CT revealed a large cyst on the diaphragmatic surface of the right middle lobe in Case 3 and on the posterior mediastinal surface of the left upper lobe in Case 4. Cyst incision, soft coagulation, and application of PGA sheet with fibrin glue were performed in both cases. CT performed 1 year after surgery showed no development of a pulmonary cyst or air space in these four cases. CONCLUSIONS: Pulmonary cysts newly formed after lobectomy can develop not only in COPD or IP but also in healthy lungs. Our findings suggest that incision of the cyst and application of fibrin glue and PGA sheet with or without suturing the cyst wall is effective for management.

Time dependency and unique etiology of barotrauma in COVID-19: A retrospective cohort study with landmark analysis and pathological approach.

BACKGROUND: Barotrauma frequently occurs in coronavirus disease 2019. Previous studies have reported barotrauma to be a mortality-risk factor; however, its time-dependent nature and pathophysiology are not elucidated. To investigate the time-dependent characteristics and the etiology of coronavirus disease 2019-related-barotrauma. METHODS AND FINDINGS: We retrospectively reviewed intubated patients with coronavirus disease 2019 from March 2020 to May 2021. We compared the 90-day survival between the barotrauma and non-barotrauma groups and performed landmark analyses on days 7, 14, 21, and 28. Barotrauma within seven days before the landmark was defined as the exposure. Additionally, we evaluated surgically treated cases of coronavirus disease 2019-related pneumothorax. We included 192 patients. Barotrauma developed in 44 patients (22.9%). The barotrauma group's 90-day survival rate was significantly worse (47.7% vs. 82.4%, p < 0.001). In the 7-day landmark analysis, there was no significant difference (75.0% vs. 75.7%, p = 0.79). Contrastingly, in the 14-, 21-, and 28-day landmark analyses, the barotrauma group's survival rates were significantly worse (14-day: 41.7% vs. 69.1%, p = 0.044; 21-day: 16.7% vs. 62.5%, p = 0.014; 28-day: 20.0% vs. 66.7%, p = 0.018). Pathological examination revealed a subpleural hematoma and pulmonary cyst with heterogenous lung inflammation. CONCLUSIONS: Barotrauma was a poor prognostic factor for coronavirus disease 2019, especially in the late phase. Heterogenous inflammation may be a key finding in its mechanism. Barotrauma is a potentially important sign of lung destruction.

The effect of polyglycolic acid sheet in preventing postoperative recurrent pneumothorax: a prospective cohort study.

BACKGROUND: Primary spontaneous pneumothorax occasionally relapses, even after bullectomy; therefore, coverage of the bullectomy staple line for pleural reinforcement is common in Japan. However, the appropriate covering materials have not yet been determined. METHODS: This was a longitudinal prospective cohort study. Data were available for patients aged < 40 years with primary spontaneous pneumothorax who underwent their first thoracoscopic bullectomy between July 2015 and June 2021. We used oxidized regenerated cellulose (ORC) sheets from July 2015 to June 2018, and polyglycolic acid (PGA) sheets from July 2018 to June 2021. The postoperative recurrence-free survival rate was evaluated. The characteristics of the recurrent cases (radiographic, intraoperative, and pathological findings) were also evaluated. The extent of pleural adhesions was classified into the following three groups: none, medium, or extensive. RESULTS: A total of 187 patients were included in the study. There were 92 and 95 participants in the ORC and PGA sheet groups, respectively. The postoperative recurrence-free survival rates were significantly higher in the PGA sheet group than in the ORC sheet group (ORC group vs. PGA group, 82.9% vs. 95.4%, p = 0.031). In recurrent cases, there was a significant difference in terms of pleural adhesion (0.0% [12 of 12, none] vs. 100.0% [four of four, extensive], p < 0.001). CONCLUSIONS: Compared with ORC sheets, PGA sheets are an effective material for preventing early recurrence of primary spontaneous pneumothorax. Strong local pleural adhesions potentially contribute to decreasing recurrence.

Multiple nuclear localization sequences in SRSF4 protein.

SRSF4 is one of the members of serine-/arginine (SR)-rich protein family involved in both constitutive and alternative splicing. SRSF4 is localized in the nucleus with speckled pattern, but its nuclear localization signal was not determined. Here, we have identified nuclear localization signals (NLSs) of SRSF4 by using a pyruvate kinase fusion system. As expected, arginine-/serine (RS)-rich domain of SRSF4 confers nuclear localization activity when it is fused to PK protein. We then further delineated the minimum sequences for nuclear localization in RS domain of SRSF4. Surprisingly, RS-rich region does not always have a nuclear localization activity. In addition, basic amino acid stretches that resemble to classical-type NLSs were identified. These results strongly suggest that SRSF4 protein uses two different nuclear import pathways with multiple NLSs in RS domain.

[A CASE OF MUCIN-PRODUCING UROTHELIAL-TYPE ADENOCARCINOMA OF THE PROSTATE (MPUAP) WITH LONG-TERM SURVIVAL AFTER TOTAL CYSTECTOMY].

Mucin-producing urothelial-type adenocarcinoma of the prostate (MPUAP) is a very rare disease. MPUAP has been reported to progress faster than the rate at which normal prostate cancer progresses. We report a case of MPUAP with long-term survival. The patient was a 65-year-old man. Computed tomography and magnetic resonance imaging showed a cystic lesion extending from the prostate to the urethra. We performed transrectal prostate biopsy and transurethral resection of the tumor, and the pathological diagnosis was adenocarcinoma. Subsequently, we performed total cystectomy, ureterostomy, and pelvic lymphadenectomy. Based on the pathological and immunostaining findings (prostate-specific antigen negativity, CDX-2 positivity, cytokeratin 20 positivity, 34ß-E12 positivity), the patient was diagnosed with MPUAP. Four years after the surgery, recurrence or metastasis was not observed.