Metformin in aging and aging-related diseases: clinical applications and relevant mechanisms.

Aging is a natural process, which plays a critical role in the pathogenesis of a variety of diseases, i.e., aging-related diseases, such as diabetes, osteoarthritis, Alzheimer disease, cardiovascular diseases, cancers, obesity and other metabolic abnormalities. Metformin, the most widely used antidiabetic drug, has been reported to delay aging and display protective effect on attenuating progression of various aging-related diseases by impacting key hallmark events of aging, including dysregulated nutrient sensing, loss of proteostasis, mitochondrial dysfunction, altered intercellular communication, telomere attrition, genomic instability, epigenetic alterations, stem cell exhaustion and cellular senescence. In this review, we provide updated information and knowledge on applications of metformin in prevention and treatment of aging and aging-related diseases. We focus our discussions on the roles and underlying mechanisms of metformin in modulating aging and treating aging-related diseases.

Ischemic Necrosis of Lower Extremity in COVID-19: A Case Report.

Coronavirus disease 2019 (COVID-19), which is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is an acute infectious disease that spreads mainly via the respiratory route. Elderly patients or those with underlying diseases are more seriously affected. We report a case of COVID-19 infection in a geriatric patient with arteriovenous thrombosis of the right lower limb. Despite persistent anticoagulant therapy, the patient's arterial thrombosis continued to progress and presented with ischemic necrosis of the lower extremity. After amputation in this case, the levels of D-dimer and inflammatory cytokine increased progressively, and he presented with acute myocardial infarction, which progressed rapidly to multisystem organ failure. However, whether coronavirus can directly cause the damage of the cardiovascular system and thrombosis needs further investigation.

Surgical treatment of thoracolumbar fracture with incomplete lower limb paralysis in a patient with COVID-19.

Since December 2019, COVID-19, an acute infectious disease, has gradually become a global threat. We report a case of thoracolumbar fractures (T12 and L1) and incomplete lower limb paralysis in a patient with COVID-19. After a series of conservative treatment which did not work at all, posterior open reduction and pedicle screw internal fixation of the thoracolumbar fracture were performed in Wuhan Union Hospital. Three weeks later, the patient could stand up and the pneumonia is almost cured. We successfully performed a surgery in a COVID-19 patient, and to our knowledge it is the first operation for a COVID-19 patient ever reported.

Recommendations of protective measures for orthopedic surgeons during COVID-19 pandemic.

PURPOSE: It was the primary purpose of the present systematic review to identify the optimal protection measures during COVID-19 pandemic and provide guidance of protective measures for orthopedic surgeons. The secondary purpose was to report the protection experience of an orthopedic trauma center in Wuhan, China during the pandemic. METHODS: A systematic search of the PubMed, Cochrane, Web of Science, Google Scholar was performed for studies about COVID-19, fracture, trauma, orthopedic, healthcare workers, protection, telemedicine. The appropriate protective measures for orthopedic surgeons and patients were reviewed (on-site first aid, emergency room, operating room, isolation wards, general ward, etc.) during the entire diagnosis and treatment process of traumatic patients. RESULTS: Eighteen studies were included, and most studies (13/18) emphasized that orthopedic surgeons should pay attention to prevent cross-infection. Only four studies have reported in detail how orthopedic surgeons should be protected during surgery in the operating room. No detailed studies on multidisciplinary cooperation, strict protection, protection training, indications of emergency surgery, first aid on-site and protection in orthopedic wards were found. CONCLUSION: Strict protection at every step in the patient pathway is important to reduce the risk of cross-infection. Lessons learnt from our experience provide some recommendations of protective measures during the entire diagnosis and treatment process of traumatic patients and help others to manage orthopedic patients with COVID-19, to reduce the risk of cross-infection between patients and to protect healthcare workers during work. LEVEL OF EVIDENCE: IV.