Persistent air leak secondary to pneumothorax in COVID-19: A case report and review of literature.

An air leak is a pathologic communication between an area of the endobronchial tree and the pleural space, causing continued air flow. The communication can originate from a distal portion of the airway, causing an alveolar-pleural fistula, or from a more proximal airway, causing a bronchopleural fistula. When the air leak persists beyond 5-7 days, it is classified as persistent air leak (PAL). PAL has serious implications on patient management and outcomes, such as prolonged chest tube maintenance, high rate of infections, ventilation-perfusion mismatch, and prolonged hospital stay with higher morbidity and mortality. There are currently no guidelines for the management of PAL in COVID-19 patients. We presented a case of PAL in a patient with COVID-19-associated pneumothorax successfully treated with a one-way endobronchial valve. We also reviewed current published cases of PAL secondary to COVID-19-associated pneumothorax and the various methods they were treated. The first line treatment was insertion of one or more chest tubes, but the persistence of an air leak then led to other treatment modalities. Initial early surgical evaluation followed by pleurodesis is recommended for the management of PAL. The most common surgical approaches include VATS or open thoracotomy with mechanical or chemical pleurodesis or pleurectomy. However, surgery is not always a feasible option for critically ill patients. In such cases, there are multiple less invasive options for the management of PAL, including implantable devices, such as Watanabe spigots and stents, and chemical agents, such as thermal treatments, hemostatic substances, and tissue adhesives.

Prognostic indicators of survival in patients with small-cell lung cancer at a tertiary care center in Lebanon.

OBJECTIVE: Small-cell lung cancer is a very aggressive tumor associated with high invasiveness and ease of metastasis and therefore poor prognosis. In the literature, several demographical, clinical as well as pathological factors including age, stage, gender and smoking were cited as independent prognosticators of survival. MATERIAL AND METHODS: This is a retrospective cohort study that includes 222 patients diagnosed with small-cell lung cancer between 2010 and 2019. Clinical and demographic data were extracted from their medical records. The Kaplan-Meier and logistic regression models of statistical analysis were used to evaluate the association of these variables with survival. RESULTS: Forty-five percent of patients were found to be alive at the time of data collection. The median survival of patients with small-cell lung cancer was found to be 14 months. On univariate analysis, increasing age as well as stage (extensive disease) were found to be significantly associated with decreased survival at 3 years. On the contrary, both gender and smoking status at diagnosis were not shown to significantly influence survival. On multivariate analysis, both age as well as stage remained significantly associated with survival. CONCLUSION: Limited data exist in the literature regarding the prognostic indicators of survival in small-cell lung cancer, especially from the Middle East area. In our study, both age and stage at the time of diagnosis were found to significantly influence survival. Further studies are needed to assess the association of other factors with survival.

Neoadjuvant chemotherapy and Avelumab in early stage resectable nonsmall cell lung cancer.

Multiple randomized studies have shown that combination of chemotherapy and immune checkpoint inhibitors (ICIs) leads to better response rates and survival as compared to chemotherapy alone in the advanced stage of NSCLC. Data suggesting a benefit to using ICIs in the neoadjuvant therapy of patients with early stage NSCLC are emerging. Eligible subjects were treatment naïve patients with stage IB, II, and resectable IIIA NSCLC. Patients received three cycles of neoadjuvant chemotherapy with four doses of avelumab every 2 weeks. Patients with squamous cell cancer received cisplatin or carboplatin on day 1 and gemcitabine on days 1 and 8 of each cycle of chemotherapy. Patients with nonsquamous histology received cisplatin or carboplatin with pemetrexed on day 1 of each cycle. Patients then proceeded to their planned surgery. Out of 15 patients accrued as part of stage 1 of the study, four had a radiologic response (1 complete response), lower than the minimum of six responses needed to continue to phase 2 of the study. The study was therefore terminated. Majority had adenocarcinoma histology and stage IIIA disease. The treatment was well tolerated with no unexpected side effects. Four patients (26.7%) had grade III/IV CTCAE toxicity. This study confirms that the preoperative administration of chemotherapy and avelumab is safe. There was no indication of increased surgical complications. The benefit of adding immunotherapy to chemotherapy did not appear to enhance the overall response rate of patients in the neoadjuvant setting in patients with resectable NSCLC because this study failed to meet its primary endpoint.

Pan-neurexin perturbation results in compromised synapse stability and a reduction in readily releasable synaptic vesicle pool size.

Neurexins are a diverse family of cell adhesion molecules that localize to presynaptic specializations of CNS neurons. Heterologous expression of neurexins in non-neuronal cells leads to the recruitment of postsynaptic proteins in contacting dendrites of co-cultured neurons, implicating neurexins in synapse formation. However, isoform-specific knockouts of either all α- or all ß-neurexins show defects in synaptic transmission but an unaltered density of glutamatergic synapses, a finding that argues against an essential function of neurexins in synaptogenesis. To address the role of neurexin in synapse formation and function, we disrupted the function of all α- and ß-neurexins in cultured hippocampal neurons by shRNA knockdown or by overexpressing a neurexin mutant that is unable to bind to postsynaptic neurexin ligands. We show that neurexin perturbation results in an attenuation of neurotransmitter release that is in large part due to a reduction in the number of readily releasable synaptic vesicles. We also find that neurexin perturbation fails to alter the ability of neurons to form synapses, but rather leads to more frequent synapse elimination. These experiments suggest that neurexins are dispensable for the formation of initial synaptic contacts, but play an essential role in the stabilization and functional maturation of synapses.