In orthopedics, bone fixation imposes the use of implants in almost all cases. Over time, the materials used for the implant have evolved from inert materials to those that mimic the morphology of the bone. Therefore, bioabsorbable, biocompatible, and bioactive materials have emerged. Our study aimed to review the main types of implant materials used in orthopedics and present their advantages and drawbacks. We have searched for the pros and cons of the various types of material in the literature from over the last twenty years. The studied data show that consecrated metal alloys, still widely used, can be successfully replaced by new types of polymers. The data from the literature show that, by manipulating their composition, the polymeric compounds can simulate the structure of the different layers of human bone, while preserving its mechanical characteristics. In addition, manipulation of the polymer composition can provide the initiation of desired cellular responses. Among the implanting materials, polyurethane is distinguished as the most versatile polymeric material for use both as orthopedic implants and as material for biomechanical testing of various bone reduction and fixation techniques.
One of the essential regulators of arterial blood pressure, the renin-angiotensin-aldosterone system (RAAS) seems to be one of the most complex mechanisms in the human body. Since the discovery of its key components and their actions, new substances and functions are still being unraveled. The main pathway begins with the secretion of renin in the kidney and culminates with the synthesis of angiotensin II (Ang II)—a strong vasoconstrictor—thanks to the angiotensin-converting enzyme (ACE). Research conducted in 2000 identified another enzyme, named ACE2, that converts Ang II into Ang-(1–7), a heptapeptide with opposing effects to those of Ang II: vasodilation and anti-inflammatory properties. This particular enzyme became of paramount importance during the last two decades, as a result of the confrontation of the human race with life-threatening epidemics. Multiple studies have been performed in order to uncover the link between ACE2 and human coronaviruses, the results of which we systemized in order to create an overview of the pathogenic mechanism. Human coronaviruses, such as SARS-CoV and SARS-CoV-2, attach to ACE2 via their spike proteins (S), causing the destruction of the enzyme. Because ACE2 limits the production of Ang II (by converting it into Ang-(1–7)), its destruction leads to a dysregulated inflammatory response. The purpose of this review is to decipher the complex pathophysiological mechanisms underlying the multiorgan complications (oral, cardiac, pulmonary, systemic) that appear as a result of the interaction of the SARS CoV-2 virus with the angiotensin-converting enzyme type 2.
Background and Objectives: Diabetes mellitus (DM) is a complex disease affecting the whole metabolic balance of the body and resulting in multiple organ complications: cardiovascular, neuronal, renal, etc. Our study focuses on investigating the effect of zinc chloride (Zn) on certain blood parameters suggestive for assessing the metabolic disturbances, the liver and kidney function, the oxidative stress and the immune defense capacity in experimental-induced DM with streptozotocin (STZ) and cholesterol in rats. Materials and Methods: The animals were assigned to three groups, as follows: Group 1 (Control): buffer citrate solution 0.1 mL/100 g body; Group 2 (STZ): 20 mg/kg body STZ and fat diet (10 g cholesterol/100 g diet); Group 3 (STZ+Zn): 20 mg/kg body STZ + 5 mg/kg body Zn chloride and the same fat diet. DM was induced by administering STZ in a single take daily, for three consecutive days, Zn and citrate buffer were administered orally for a month. The protocol was approved by the Ethics Committee of the University ‘Grigore T Popa’ Iasi, in agreement with the International Regulations about the handling of laboratory animals. Results: The use of STZ in rats fed with cholesterol was correlated with important weight gain, hyperglycemia, the intensification of the transaminases activity and the increase in serum alkaline phosphatase, cholesterol, triglyceride, urea, creatinine and in malondialdehyde. Conclusions: The treatment with Zn resulted in weight loss and a decrease in blood sugar in diabetic rats. Supplementation with Zn notably reduced oxidative stress, preserved the pancreatic architecture and restored the liver and kidney function and structure in STZ-induced DM in rats.
The specialized literature emphasizes the fact that vitamin D has a potentially beneficial effect in the context of the current COVID-19 pandemic. The purpose of this article is to highlight the role of vitamin D, both prophylactic and curative, in the treatment of patients diagnosed with COVID-19. Even though its relevance is still unknown and causes various controversies, there is currently no specific treatment for patients diagnosed with COVID-19. There are various prevention strategies with new vaccination schedules, but additional randomized and clinical trials are still needed to combat this pandemic. In addition to the systemic manifestations of SARS-CoV-2 infection, oral manifestations of this disease have also been described in the literature. The etiology of oral manifestations associated with COVID-19 infection and vitamin D deficiency remains controversial. In the present studies, oral manifestations such as salivary gland infections, aphthae, erythema, gingivitis, ulcers, etc. have been reported. This is a new topic, and the prevalence of manifestations is described in only a few studies, which is inconsistent with the number of COVID-19 cases reported since the beginning of the pandemic. The clinical symptomatology in patients with current COVID-19 infection is polymorphic. Whether the oral manifestation is directly caused by SARS-CoV-2 or a secondary manifestation remains an important topic to analyze and discuss.
The liver is the main metabolic organ, having complex physiological and biochemical roles, many of these functions being in a close relationship. It is also well known that hepatitis C virus infection is associated with changes in lipid metabolism. This is evident in liver dysfunctions, when liver functions are disturbed simultaneously. The aim of this study is to evaluate the effect of antiviral therapy on serum lipid level in patients with viral hepatitis C before and at the end of the 48 weeks of treatment compared patients treated with Interferon vs Interferon + Ribavirin and relation with sustained virological response, from North East Romania. We evaluated patients hospitalized in Emergency Hospital for Children St. Mary Iasi between 2009-2017. The result of our study show that the mean age of patients from goup 1 was 11.85±3.65 years, vs 11.5±3.1 years in group 2 (p=0.171). We found changes in cholesterol metabolism in both groups of patients, increases in total cholesterol level, 21.43% of patients in the group 1 vs 32.3% in goup 2 (p=0.258) and decreases 17.86% vs 14.7% (p=0.131). At initiation of antiviral therapy mean serum cholesterol level were 155.78±36.30 mg/dL, in group 1 vs 149.88±47.22 mg/dL, for group 2. At 48 weeks of treatment in the both goups revealed significantly decreased of total cholesterol levels 136.46±41.63mg/dL, for group 1 vs 109.26±41.05, for patients in group 2 (p=0.003). Triglycerides, HDL cholesterol and LDL cholesterol did not show significant changes in the patients of the two groups. Total cholesterol level after antiviral therapy were significantly different between patients who achieved SVR and non SVR (p=0.014), group 1 vs (p=0.001), group 2. Total serum cholesterol level showed significant changes during the antiviral therapy in both monotherapy and combination therapy group.
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