Reactive oxygen species and other free radicals cause oxidative stress which is the underlying pathogenesis of cellular injury in various neurological diseases. Molecular hydrogen therapy with its unique biological property of selectively scavenging pathological free radicals has demonstrated therapeutic potential in innumerable animal studies and some clinical trials. These studies have implicated several cellular pathways affected by hydrogen therapy in explaining its anti-inflammatory and antioxidative effects. This article reviews relevant animal and clinical studies that demonstrate neuroprotective effects of hydrogen therapy in stroke, neurodegenerative diseases, neurotrauma, and global brain injury.

Hydrogen (H₂) has been widely used in the chemical industry as a reducing agent. As the researches move along, increasing attention has been paid to its biological functions. The selective antioxidant effect of hydrogen is considered to be the main reason for medical applications. So far, many studies have confirmed its potential protective effects on ischemia/reperfusion injury of multiple organs, neurodegenerative diseases, bone and joint diseases, and respiratory diseases, opening a new era in the medical research and application of H₂. Increasing studies have focused on its biological effects and molecular mechanisms in the treatment of different diseases. In this paper, we review the biological effects, molecular mechanisms and methods of H₂ supply. We do hope that the advances in materials science can be better translated into medical applications and solve clinical problems. The medical application of H₂ is promising, and how to prepare an H₂ sustained-release system to achieve a sustained and stable H₂ supply in the body and ultimately improve the therapeutic effect of H₂ is a problem worthy of further investigation.

Intestinal bacteria can be classified into “beneficial bacteria” and “harmful bacteria.” However, it is difficult to explain the mechanisms that make “beneficial bacteria” truly beneficial to human health. This issue can be addressed by focusing on hydrogen-producing bacteria in the intestines. Although it is widely known that molecular hydrogen can react with hydroxyl radicals, generated in the mitochondria, to protect cells from oxidative stress, the beneficial effects of hydrogen are not fully pervasive because it is not generally thought to be metabolized in vivo. In recent years, it has become clear that there is a close relationship between the amount of hydrogen produced by intestinal bacteria and various diseases, and this report discusses this relationship.

Electroconvulsive therapy (ECT) is one of the therapeutic opportunities for patients with psychological disorders when they may decline to take medication. We sought to systematically compare the anesthetic efficacy of ketamine, propofol, and dexmedetomidine for electroconvulsive therapy in treatment-resistant major depressive disorder patients. This double-blind trial enrolled treatment-resistant major depressive disorder patients (n = 85) who had been hospitalized for ECT in the Amir Kabir Hospital’s psychiatric ward (Arak, Iran). The ketamine, propofol, and dexmedetomidine groups received a dose of 0.2 μg/kg ketamine, 1.5 mg/kg propofol, and 0.8 mg/kg dexmedetomidine, respectively. In all intervention groups, 10 mL of interventional drugs was injected intravenously for 10 minutes, and in the placebo group, 10 mL of normal saline was given over the same period. The dexmedetomidine group’s blood pressure was revealed comparatively lower at all times. Dexmedetomidine-treated patients showed their marked satisfaction, while those treated with propofol had shorter recovery time, shorter seizure duration, and shorter time to achieve an Aldrete score of 9–10 and increased relaxation, and next dexmedetomidine produced deeper relaxation. Propofol could shorten recovery time and seizure duration, and enhance relaxation, while dexmedetomidine was associated with higher patient satisfaction. Considering that any anesthetic which does not shorten seizure duration may serve efficiently for ECT and that ketamine-treated patients had more prolonged seizure duration, the preferred drug can hence be considered from various angles, thereby offering anesthetic agents with highly favorable efficacy in treatment-resistant major depressive disorder patients needing ECT. The drug choice thus depends on physical conditions, underlying diseases, and psychiatrist consultation.

Sublingual (SL) buprenorphine is approved for managing acute postoperative pain, characterized by easy administration, good pain relief and good patient compliance. We hypothesized that SL buprenorphine would be a better perioperative analgesic compared to intravenous (IV) opioids like tramadol in patients undergoing mastectomy surgery for breast cancer. After institutional ethics committee approval, we randomized 60 patients with breast cancer into 2 groups. In buprenorphine group, patients received 200 μg of SL buprenorphine thrice daily and in tramadol group patients received 100 mg of IV tramadol thrice daily. The analgesic efficacy of SL buprenorphine was comparable to that of IV tramadol. Visual Analogue Scale scores had no significant difference between the two groups at various time frames (0, 1, 3, 6, 12, 18 and 24 hours) at rest and movement except at 0 and 3 hours during movement when the score was lower in the tramadol group than the buprenorphine group. Four patients in the buprenorphine group received rescue analgesic (IV morphine 3 mg). Analgesic efficacy of SL buprenorphine appears comparable to IV tramadol for managing postoperative pain after mastectomy. SL buprenorphine can be administered sublingually, which is an advantage.

We aimed to assess whether ropivacaine (0.75%; 22.5 mg) can replace bupivacaine (0.5%; 15 mg) as a better intrathecal anesthetic in lower abdominal surgery. In this hospital-based, single-blind, randomized, prospective, comparative study, 100 patients of either sex, aged between 18 and 70 years, weighing 40-80 kg, with American Society of Anesthesiologists physical status 1 and 2, and undergoing lower abdominal surgery were randomly allocated into two groups to receive intrathecal isobaric bupivacaine 0.5% 3 mL (15 mg) or ropivacaine 0.75% 3 mL (22.5 mg). In the intraoperative period, the onset, efficacy, duration, and regression of sensory and motor blockade and the quality of anesthesia and hemodynamic effects were observed at regular intervals. The ropivacaine and bupivacaine groups were comparable for demographic parameters. The duration of onset of sensory and motor blocks was significantly shorter in the bupivacaine group (P < 0.01). In the ropivacaine group, a faster recovery from sensory block (P = 0.02) and higher segmental height [thoracic (T)10 and T8] were achieved (P < 0.01). Bradycardia and hypotension were insignificant in the ropivacaine group (P > 0.05). Isobaric ropivacaine is a better spinal anesthetic in lower abdominal surgeries as it provides faster recovery from sensory block and a higher level of segmental sensory block with fewer side-effects.

Nitric oxide can activate neutrophils and macrophages, facilitate the synthesis of collagen, which allows significantly accelerating the regeneration of traumatized tissues. We studied the effects of nitric oxide-containing gas flow generated by plasma-chemical device “Plason” in a rat model of full-thickness wounds. Histological and morphometric analyses revealed that Plason treated wounds expressed significantly fewer signs of inflammation and contained a more mature granulation tissue on day 4 after the operation. Considering the results of the experimental study, we applied the Plason device in sports medicine for the treatment of lower limb bruises of 34 professional soccer players. Athletes were asked to assess the intensity of pain with the Visual Analogue Scale. Girths of their lower limbs were measured over the course of rehabilitation. Nitric oxide therapy of full-thickness wounds inhibited inflammation and accelerated the regeneration of skin and muscle tissues. Compared with the control, we observed a significant reduction in pain syndrome on days 2–7 after injuries, edema, and hematoma, and shortened treatment duration. This pilot study indicates that the use of nitric oxide is a promising treatment method for sports injuries.

Molecular hydrogen (H₂) is an antioxidant and anti-inflammatory agent; however, the molecular mechanisms underlying its biological effects are largely unknown. Similar to other gaseous molecules such as inhalation anesthetics, H₂ is more soluble in lipids than in water. A recent study demonstrated that H₂ reduces radical polymerization-induced cellular damage by suppressing fatty acid peroxidation and membrane permeability. Thus, we sought to examine the effects of short exposure to H₂ on lipid composition and associated physiological changes in SH-SY5Y neuroblastoma cells. We analyzed cells by liquid chromatography-high-resolution mass spectrometry to define changes in lipid components. Lipid class analysis of cells exposed to H₂ for 1 hour revealed transient increases in glycerophospholipids including phosphatidylethanolamine, phosphatidylinositol, and cardiolipin. Metabolomic analysis also showed that H₂ exposure for 1 hour transiently suppressed overall energy metabolism accompanied by a decrease in glutathione. We further observed alterations to endosomal morphology by staining with specific antibodies. Endosomal transport of cholera toxin B to recycling endosomes localized around the Golgi body was delayed in H₂-exposed cells. We speculate that H₂-induced modification of lipid composition depresses energy production and endosomal transport concomitant with enhancement of oxidative stress, which transiently stimulates stress response pathways to protect cells.

Acrylonitrile is a potential carcinogen for humans, and exposure to this substance can cause adverse effects for workers. This study aimed to carcinogenic and health risk assessment of acrylonitrile vapor exposure in exposed personnel of a petrochemical complex. This crosssectional study was performed in 2019 in a petrochemical complex. In this study, to sample and determine acrylonitrile’s respiratory exposure, the method provided by the National Institute of Occupational Safety and Health (NIOSH 1601) was used, and a total of 45 inhaled air samples were sampled from men workers, aged 39.43 ± 9.37 years. All subjects’ mean exposure to acrylonitrile vapors was 71.1 ± 122.8 μg/m³. Also, the mean exposure index among all subjects was 0.02 ± 0.034. The non-carcinogenic risk assessment results showed that the mean Hazard quotient index was 4.04 ± 6.93. The mean lifetime cancer risk index was also 2.1 × 10^-3 ± 3.5 × 10^-3 and was in the definite risk range. Considering that both carcinogenicity and health indicators of exposure to acrylonitrile in the studied petrochemical complex are more than the recommended limits, the necessary engineering and management measures to control and manage the risk to an acceptable level are essential to improving the worker’s health.

Temporomandibular joint disorders (TMD) generate pain and difficulties for mouth opening affecting the patients’ quality of life. Ozone is an emerging therapy that has been proposed as a potential treatment, due to that, the evidence about its efficacy should be reviewed. Therefore, this work aimed to conduct a comprehensive systematic review to address the efficacy of ozone therapy for the treatment of pain and limited mouth opening in patients with TMD. The design of the included studies was clinical trials and observational studies, whereas, a series of cases, in vivo, and in vitro studies were excluded. The search was performed in PubMed, ClinicalTrials, Web of Science, and Scopus. Gray literature was searched at Google Scholar. Relevant data of all included studies were recorded. The risk of bias (using RoB 2) and the quality (using Grading of Recommendations Assessment, Development, and Evaluation) assessments were carried out. Meta-analyses using random-effects models of pain and maximal mouth opening data were performed. This review included 8 studies with 404 participants suffering limited function and pain related to TMD. At the overall bias of the studies, 25% exhibited some concerns and 75% had high risk; and the quality of the studies was low. The analysis of the included studies suggests that ozone therapy can diminish pain and improve the maximal mouth opening in TMD patients. However, there is no conclusive evidence of ozone therapy as a superior treatment for TMD compared with occlusal splint and pharmacotherapy.

Bacterial cystitis is a common clinical problem among cats and dogs and is one of the main reasons for the administration of antimicrobials. This can cause serious damage to public and animal health, as this practice facilitates the selection of bacteria that are multidrug-resistant to antibiotics. In this context, it is urgent to understand and validate therapeutic modalities that complement antimicrobial treatment in cystitis cases. Ozone therapy has been proposed by scientists owing to the various mechanisms of action in a range of pathologies, both in human and animal medicine. This paper describes the bactericidal action of two different protocols of bladder irrigation with ozonized saline solution (59 μg/mL) in a paraplegic canine with recurrent bacterial cystitis caused by Proteus spp. In the first protocol, the bladder instillations were applied once a day for three consecutive days while in the second, successive lavages were performed throughout the day until a significant reduction in the presence of bacteria in the urine sediment. In this study, we were able to demonstrate that repeated bladder instillation within 24 hours was the most effective treatment for Proteus compared to a single instillation on successive days.