Pathological features and diagnostic significance of lung biopsy in occupational lung diseases / 中华病理学杂志

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.

Relationship between right ventricular pacing and non-sustained ventricular arrhythmias in patients with dual-chamber pacemaker and normal range left ventricular ejection fraction

Background@#Right ventricular pacing (RVP) increases heart failure, AF, and death rates in pacemaker patients and ventricular arrhythmias (VAs) in defibrillator patients. However, the impact of RVP on VAs burden and its clinical significance in pacemaker patients with normal range LVEF of > 50–55% remains unknown. We sought to evaluate the relationship of RVP and VAs and its clinical impact in a pacemaker patient population. @*Methods@#Records of 105 patients who underwent de novo dual-chamber pacemaker implant or a generator change (Medtronic™ or Boston Scientific™) for AV block and sinus node disease at a tertiary care center between September 1, 2015, and September 1, 2016, were retrospectively reviewed. @*Results@#Data from 105 patients (51% females, mean age 76 ± 1 years, mean LVEF 61 ± 0.7%) without history of VAs (98.2%) were reviewed over 1044 ± 23 days. Dependent patients (100% RVP) exhibited the lowest VAs burden when compared to  1/h of PVC runs and increasing PVC runs/h were significantly associated with hospitalization (p = 0.04) and all-cause mortality (p = 0.03), respectively. @*Conclusions@#In pacemaker patients with normal range LVEF (> 50–55%), 100% RVP is associated with the lowest burden of NSVT. Furthermore, patients with < 1% RVP also exhibit low VA burden; however, intermittent RVP seems to significantly correlate with non-sustained VAs.

Tooth regeneration: a revolution in stomatology and evolution in regenerative medicine / 国际口腔科学杂志·英文版

A tooth is a complex biological organ and consists of multiple tissues including the enamel, dentin, cementum and pulp. Tooth loss is the most common organ failure. Can a tooth be regenerated? Can adult stem cells be orchestrated to regenerate tooth structures such as the enamel, dentin, cementum and dental pulp, or even an entire tooth? If not, what are the therapeutically viable sources of stem cells for tooth regeneration? Do stem cells necessarily need to be taken out of the body, and manipulated ex vivo before they are transplanted for tooth regeneration? How can regenerated teeth be economically competitive with dental implants? Would it be possible to make regenerated teeth affordable by a large segment of the population worldwide? This review article explores existing and visionary approaches that address some of the above-mentioned questions. Tooth regeneration represents a revolution in stomatology as a shift in the paradigm from repair to regeneration: repair is by metal or artificial materials whereas regeneration is by biological restoration. Tooth regeneration is an extension of the concepts in the broad field of regenerative medicine to restore a tissue defect to its original form and function by biological substitutes.