PHB production by Bacillus megaterium strain MNSH1-9K-1 using low-cost media.

Plastics are widely used for diverse applications due to their versatility. However, their negative impact on ecosystems is undeniable due to their long-term degradation. Thus, there is a rising need for developing eco-friendlier alternatives to substitute fossil-based plastics, like biopolymers. PHA are synthesized intracellularly by microorganisms under stressful conditions of growth and have similar characteristics to conventional polymers, like their melting point, transition temperatures, crystallinity, and flexibility. Although it is feasible to use biopolymers for diverse industrial applications, their elevated production cost due to the supplies needed for microbiological procedures and the low productivity yields obtained have been the main limiting factors for their commercial success. The present study assessed the ability of Bacillus megaterium strain MNSH1-9K-1 to produce biopolymers using low-cost media from different kinds of fruit-peel residues. The results show that MNSH1-9K-1 can produce up to 58 g/L of PHB when grown in a medium prepared from orange-peel residues. The data obtained provide information to enhance the scalability of these kinds of biotechnological processes.

Factors Possibly Associated with Mortality in Intubated COVID-19 Patients: A Retrospective Study.

In Mexico, there is a high mortality rate among patients intubated because of COVID-19. The objective of this study was to investigate the associations of age, comorbidities, and biochemical parameters with the in-hospital mortality of COVID-19 patients. A retrospective study of 79 intubated patients admitted to one hospital in Jalisco, Mexico, between July 2020 and January 2021 was performed. Demographic and clinical characteristics were collected. The mean age was 57.7 (±12.8) years, with 83.5% non-survivors and 16.5% survivors. Age, lactate dehydrogenase (LDH) and D-dimer levels were found to be significantly higher in the non-survivor group (p = 0.011, p = 0.026, p = 0.007, respectively). Patients ≥58 years had a high risk of mortality (OR = 7.017). Significant correlations were also found in some of the study variables: LDH levels and leukocyte count (r = 0.388, p = 0.034) and CRP levels and fibrinogen (r = 0.692, p ˂ 0.001) in the patients ˂58 years. Leukocyte count with LDH levels (r = 0.381, p = 0.024) were significant in the group ≥58 years. No significant difference was observed in the presence of diabetes mellitus (DM) and hypertension. In conclusion, according to logistic regression analysis, age over 58 years represents the main factor associated with mortality in these patients.

Antioxidant and Anti-Inflammatory Effects of Coenzyme Q10 Supplementation on Infectious Diseases.

With the appearance of new viruses and infectious diseases (ID) such as COVID-19 in 2019, as well as the lack of specific pharmacological tools for the management of patients with severe complications or comorbidities, it is important to search for adjuvant treatments that help improve the prognosis of infectious disease patients. It is also important that these treatments limit the oxidative and hyperinflammatory damage caused as a response to pathogenic agents, since, in some cases, an inflammatory syndrome may develop that worsens the patient's prognosis. The potential benefits of complementary nutrients and dietary interventions in the treatment of pathological processes in which oxidative stress and inflammation play a fundamental role have been widely evaluated. Coenzyme Q10 (CoQ10) is a supplement that has been shown to protect cells and be effective in cardiovascular diseases and obesity. Additionally, some studies have proposed it as a possible adjuvant treatment in viral infections. Preclinical and clinical studies have shown that CoQ10 has anti-inflammatory and antioxidant effects, and effects on mitochondrial dysfunction, which have been linked to the inflammatory response.

Oxidative Stress, Apoptosis, and Mitochondrial Function in Diabetic Nephropathy.

Diabetic nephropathy (DN) is the second most frequent and prevalent complication of diabetes mellitus (DM). The increase in the production of oxidative stress (OS) is induced by the persistent hyperglycemic state capable of producing oxidative damage to the macromolecules (lipids, carbohydrates, proteins, and nucleic acids). OS favors the production of oxidative damage to the histones of the double-chain DNA and affects expression of the DNA repairer enzyme which leads to cell death from apoptosis. The chronic hyperglycemic state unchains an increase in advanced glycation end-products (AGE) that interact through the cellular receptors to favor activation of the transcription factor NF-κB and the protein kinase C (PKC) system, leading to the appearance of inflammation, growth, and augmentation of synthesis of the extracellular matrix (ECM) in DN. The reactive oxygen species (ROS) play an important role in the pathogenesis of diabetic complications because the production of ROS increases during the persistent hyperglycemia. The primary source of the excessive production of ROS is the mitochondria with the capacity to exceed production of endogenous antioxidants. Due to the fact that the mechanisms involved in the development of DN have not been fully clarified, there are different approaches to specific therapeutic targets or adjuvant management alternatives in the control of glycemia in DN.

Effect of statins on oxidative DNA damage in diabetic polyneuropathy.

Oxidative stress induces nerve damage in type 2 diabetes mellitus and leads to diabetic polyneuropathy (DPN) and can affect the DNA and antioxidant status. Statins have pleiotropic, protective effects on the peripheral nerves of patients with diabetes. The aim of this study was to determine the effects of ezetimibe/simvastatin and rosuvastatin on DNA damage in patients with DPN. This randomized, double-blind, placebo-controlled, clinical trial comprised outpatients from Guadalajara, Mexico. The inclusion criteria were either gender, age 35-80 years, type 2 diabetes, glycated hemoglobin ≤10%, diabetic polyneuropathy stage 1/2, and signed informed consent. Patients who were taking antioxidant therapy or statins, had hypersensitivity to drugs, experienced organ failure, were pregnant or breastfeeding, or had other types of neuropathy were excluded. We assigned patients to placebo, ezetimibe/simvastatin 10/20 mg, or rosuvastatin 20 mg, and the primary outcomes were 8-hydroxy-2'-deoxyguanosine (8-OHdG) for DNA damage, 8-oxoguanine-DNA-N-glycosilase (hOGG1) for DNA repair, and superoxide dismutase (SOD). Seventy-four patients were recruited. Nine patients were included as negative controls. There were no differences in 8-OHdG between the healthy subjects (4.68 [3.53-6.38] ng/mL) and the DPN patients (4.51 [1.22-9.84] ng/mL), whereas the hOGG1 level was 0.39 (0.37-0.42) ng/mL in the healthy subjects and 0.41 (0.38-0.54) ng/mL in patients with DPN at baseline (p = 0.01). SOD decreased significantly in patients with DPN (5.35 [0.01-17.90] U/mL) compared with the healthy subjects (9.81 [8.66-12.61] U/mL) at baseline (p < 0.001). No significant changes in DNA biomarkers were observed in any group between baseline and final levels. We noted a rise in hOGG1 in patients with DPN, without modifications after treatment. There was a slight, albeit insignificant, increase in SOD in patients who were on statins.

Markers of Oxidative Stress and Inflammation in Ascites and Plasma in Patients with Platinum-Sensitive, Platinum-Resistant, and Platinum-Refractory Epithelial Ovarian Cancer.

Diverse proinflammatory biomarkers and oxidative stress are strongly associated with advanced epithelial ovarian cancer (EOC). Objective. To determine the behavior of markers of oxidative stress and inflammation in plasma and ascites fluid in patients with platinum-sensitive, platinum-resistant, and platinum-refractory EOC. Methods. A prospective cohort study. The colorimetric method was used to determine levels of the markers 8-isoprostanes (8-IP), lipid peroxidation products (LPO), and total antioxidant capacity (TAC) in plasma and ascites fluid; and with ELISA, the levels of interleukin-6 (IL-6) and tumor necrosis factor alpha (TNF-α) were determined in patients with EOC. Results. In ascites fluid, a significant increase in 8-IP versus baseline plasma levels was found (p = 0.002). There was an important leakage of the TAC levels in ascites fluid versus baseline plasma levels (p < 0.001). The IL-6 was elevated in ascites fluid versus baseline plasma levels (p = 0.003), and there were diminished levels of TNF-α in ascites fluid versus baseline plasma levels (p = 0.001). Discussion. We hypothesize that the ascites fluid influences the behavior and dissemination of the tumor. Deregulation between oxidants, antioxidants, and the proinflammatory cytokines was found to vary among platinum-sensitive, platinum-resistant, and platinum-refractory patients.

The Oxidative and Inflammatory State in Patients with Acute Renal Graft Dysfunction Treated with Tacrolimus.

Objective. To determine the oxidative stress/inflammation behavior in patients with/without acute graft dysfunction (AGD) with Tacrolimus. Methods. Cross-sectional study, in renal transplant (RT) recipients (1-yr follow-up). Patients with AGD and without AGD were included. Serum IL-6, TNF-α, 8-isoprostanes (8-IP), and Nitric Oxide (NO) were determined by ELISA; C-reactive protein (CRP) was determined by nephelometry; lipid peroxidation products (LPO) and superoxide dismutase (SOD) were determined by colorimetry. Results. The AGD presentation was at 5.09 ± 3.07 versus 8.27 ± 3.78 months (p < 0.001); CRP >3.19 mg/L was found in 21 versus 19 in the N-AGD group (p = 0.83); TNF-α 145.53 ± 18.87 pg/mL versus 125.54 ± 15.92 pg/mL in N-AGD (p = 0.64); IL-6 2110.69 ± 350.97 pg/mL versus 1933.42 ± 235.38 pg/mL in N-AGD (p = 0.13). The LPO were higher in AGD (p = 0.014): 4.10 ± 0.69 µM versus 2.41 ± 0.29 µM; also levels of 8-IP were higher in AGD 27.47 ± 9.28 pg/mL versus 8.64 ± 1.54 pg/mL (p = 0.01). Serum levels of NO in AGD were lower 138.44 ± 19.20 µmol/L versus 190.57 ± 22.04 µmol/L in N-AGD (p = 0.042); antioxidant enzyme SOD activity was significantly diminished in AGD with 9.75 ± 0.52 U/mL versus 11.69 ± 0.55 U/mL in N-AGD (p = 0.012). Discussion. Patients with RT present with a similar state of the proinflammatory cytokines whether or not they have AGD. The patients with AGD showed deregulation of the oxidative state with increased LPO and 8-IP and decreased NO and SOD.

The Beneficial Effects of Renal Transplantation on Altered Oxidative Status of ESRD Patients.

Renal transplantation (RT), has been considered the best therapeutic option for end stage renal disease (ESRD). Objective. To determine the effect of RT on the evolution of oxidative DNA status. Methods. Prospective cohort (N = 50 receptors of RT); genotoxic damage, 8-hydroxy-2'-deoxyguanosine (8-OHdG), and DNA repair enzyme, human 8-oxoguanine-DNA-N- glycosylase-1 (hOGG1); and antioxidants, superoxide dismutase (SOD) and glutathione peroxidase (GPx), were evaluated. Results. Before RT, 8-OHdG were significantly elevated (11.04 ± 0.90 versus 4.73 ± 0.34 ng/mL) compared to healthy controls (p = 0.001), with normalization after 6 months of 4.78 ± 0.34 ng/mL (p < 0.001). The same phenomenon was observed with hOGG1 enzyme before RT with 2.14 ± 0.36 ng/mL (p = 0.01) and decreased significantly at the end of the study to 1.20 ng/mL (p < 0.001) but was higher than controls, 0.51 ± 0.07 ng/mL (p < 0.03). Antioxidant SOD was elevated at 24.09 ± 1.6 IU/mL versus healthy controls (p = 0.001) before RT; however, 6 months after RT it decreased significantly to 16.9 ± 1.6 IU/mL (p = 0.002), without achieving the levels of healthy controls (p = 0.01). The GPx, before RT, was significantly diminished with 24.09 ± 1.6 IU/mL versus healthy controls (39.0 ± 1.58) (p = 0.01), while, in the final results, levels increased significantly to 30.38 ± 3.16 IU/mL (p = 0.001). Discussion. Patients with ESRD have important oxidative damage before RT. The RT significantly reduces oxidative damage and partially regulates the antioxidant enzymes (SOD and GPx).