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Successful multichannel intraluminal impedance and pH monitoring (MII-pHM) studies rely on constant attendants (CAs) or family members (and sometimes the patients themselves) to assist in the execution and facilitation of the MII-pHM study. While "pushing buttons" [corresponding to specific symptoms, body position (upright versus recumbent), and meal start and stop times] on the MII-pHM system recording box is indeed a big part of MII-pHM study execution and facilitation, there are other concerns and duties that are equally as important. This paper outlines some of the important duties of the study facilitator (or patient) during a MII-pHM study. When provided with the proper training, study facilitators invigilating the MII-pHM study will be better able to contribute to the data collection process and ultimately to produce data that when analyzed will lead to better interpretations, clinical recommendations, and good clinical outcomes. When executed properly, MII-pHM studies have the potential to assess diurnal exposure of the esophageal mucosa to gastric/duodenal contents, provide insight regarding the proximal extent of gastroesophageal reflux (GER), provide a measurement of the mean esophageal pH, and assess mucosal integrity and temporal relationship between GER and the symptoms of interest. While several groups have offered recommendations for proper execution of the MII-pHM study, to our knowledge, there have not been publications wherein recommendations were compiled to form a single source document.
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In recent decades, there has been a growing interest in optimizing the protocols intended to sperm cryopreservation in domestic animals. These protocols include initial cooling, freezing, and thawing. While different attempts have been devised to improve sperm cryopreservation, the efficiency of this reproductive biotechnology is still far from being optimal. Furthermore, while much attention in improving cooling/freezing, less emphasis has been made in how thawing can be ameliorated. Despite this, the conditions through which, upon thawing, sperm return to physiological temperatures are much relevant, given that these cells must travel throughout the female genital tract until they reach the utero-tubal junction. Moreover, the composition of the media used for artificial insemination (AI) may also affect sperm survival, which is again something that one should bear because of the long journey that sperm must make. Furthermore, sperm quality and functionality decrease dramatically during post-thawing incubation time. Added to that, the deposition of the thawed sperm suspension devoid of seminal plasma in some species during an AI is accompanied by a leukocyte migration to the uterine lumen and with it the activation of immune mechanisms. Because few reviews have focused on the evidence gathered after sperm thawing, the present one aims to compile and discuss the available information concerning ruminants, pigs and horses.
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Animais Domésticos , Criopreservação , Inseminação Artificial , Preservação do Sêmen , Animais , Criopreservação/veterinária , Criopreservação/métodos , Preservação do Sêmen/veterinária , Preservação do Sêmen/métodos , Masculino , Inseminação Artificial/veterinária , Espermatozoides/fisiologia , Temperatura , Crioprotetores/farmacologia , Fatores de Tempo , Cavalos/fisiologiaRESUMO
OBJECTIVES: Ineffective esophageal motility (IEM) on high-resolution manometry (HRM) is not consistently associated with specific clinical syndromes or outcomes. We evaluated the prevalence, clinical features, management, and outcomes of pediatric IEM patients across the United States. METHODS: Clinical and manometric characteristics of children undergoing esophageal HRM during 2021-2022 were collected from 12 pediatric motility centers. Clinical presentation, test results, management strategies, and outcomes were compared between children with IEM and normal HRM. RESULTS: Of 236 children (median age 15 years, 63.6% female, 79.2% Caucasian), 62 (23.6%) patients had IEM, and 174 (73.7%) patients had normal HRM, with similar demographics, medical history, clinical presentation, and median symptom duration. Reflux monitoring was performed more often for IEM patients (25.8% vs. 8.6%, p = 0.002), but other adjunctive testing was similar. Among 101 patients with follow-up, symptomatic cohorts declined in both groups in relation to the initial presentation (p > 0.107 for each comparison) with management targeting symptoms, particularly acid suppression. Though prokinetics were used more often and behavioral therapy less often in IEM (p ≤ 0.015 for each comparison), symptom outcomes were similar between IEM and normal HRM. Despite a higher proportion with residual dysphagia on follow-up in IEM (64.0% vs. 39.1%, p = 0.043), an alternate mechanism for dysphagia was identified more often in IEM (68.8%) compared to normal HRM (27.8%, p = 0.017). CONCLUSIONS: IEM is a descriptive manometric pattern rather than a clinical diagnosis requiring specific intervention in children. Management based on clinical presentation provides consistent symptom outcomes.
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Bovine spermatozoa are highly susceptible to oxidative stress (OS), and it is known to affect their cellular functions. The main leukocyte producers of reactive oxygen species (ROS) in mammalian semen are polymorphonuclear neutrophils (PMN). PMN activation can result in the formation of neutrophil extracellular traps (NETs), which have been shown to affect the motility and function of spermatozoa. However, OS effects on bull spermatozoa derived from individual NETs components have not been investigated. The hypothesis of this study was that specific NETs components might generate OS on bull spermatozoa. Bovine sperm cells were incubated with five NETs-associated molecules, including 30 µg/mL histone 2A (H2A), neutrophil elastase (NE), 1 µg/mL myeloperoxidase (MPO), cathepsin G (Cat-G), and cathelicidin LL37 (LL-37), for a time course ranging from 15 to 240 min. Fluorescence microscopy was used to evaluate the coincubation of bovine PMN and sperm cells. Within 15 min, H2A, NE, and LL-37 caused membrane disruption, while MPO and Cat-G caused OS on bull spermatozoa after 1 h of coincubation. NET formation was observed within 15 min of coincubation in co-cultures of bovine PMN/sperm cells. This study is the first to report on the role of cytotoxic OS effects caused by NETs-derived components in bovine sperm in vitro.
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Oxidative stress (OS) and disrupted antioxidant defense mechanisms play a pivotal role in the etiology of male infertility. The alterations in reactive oxygen species (ROS) production and calcium (Ca2+) homeostasis are the main activators for the mitochondrial permeability transition pore (mPTP) opening. The mPTP opening is one of the main mechanisms involved in mitochondrial dysfunction in spermatozoa. This alteration in mitochondrial function adversely affects energy supply, sperm motility, and fertilizing capacity and contributes to the development of male infertility. In human spermatozoa, the mPTP opening has been associated with ionomycin-induced endogenous oxidative stress and peroxynitrite-induced nitrosative stress; however, the effect of exogenous oxidative stress on mPTP opening in sperm has not been evaluated. The aim of this study was to determine the effect of exogenous oxidative stress induced by hydrogen peroxide (H2O2) on mPTP opening, mitochondrial function, motility, and cell death markers in human spermatozoa. Human spermatozoa were incubated with 3 mmol/L of H2O2 for 60 min, and intracellular Ca2+ concentration, mPTP opening, mitochondrial membrane potential (ΔΨm), ATP levels, mitochondrial reactive oxygen species (mROS) production, phosphatidylserine (PS) externalization, DNA fragmentation, viability, and sperm motility were evaluated. H2O2-induced exogenous oxidative stress caused increased intracellular Ca2+, leading to subsequent mPTP opening and alteration of mitochondrial function, characterized by ΔΨm dissipation, decreased ATP levels, increased mROS production, and the subsequent alteration of sperm motility. Furthermore, H2O2-induced opening of mPTP was associated with the expression of apoptotic cell death markers including PS externalization and DNA fragmentation. These results highlight the role of exogenous oxidative stress in causing mitochondrial dysfunction, deterioration of sperm motility, and an increase in apoptotic cell death markers, including PS externalization and DNA fragmentation, through the mPTP opening. This study yielded new knowledge regarding the effects of this type of stress on mitochondrial function and specifically on mPTP opening, factors that can contribute to the development of male infertility, considering that the role of mPTP in mitochondrial dysfunction in human sperm is not completely elucidated. Therefore, these findings are relevant to understanding male infertility and may provide an in vitro model for further research aimed at improving human sperm quality.
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Death initiates a cascade of physiological and biochemical alterations in organs and tissues, resulting in microscopic changes that challenge the histopathological evaluation. Moreover, the brain is particularly susceptible to artifacts owing to its unique composition and its location within the cranial vault. The aim of this study was to compile and illustrate the microscopic changes in the central nervous system (CNS) of rats subjected to delayed postmortem fixation. It also scrutinizes the influence of exsanguination and cooling methods on the initiation and progression of these alterations. Twenty-four Wistar Han outbred rats (RccHan™: WIST) were sacrificed and stored either at room temperature (18-22°C) or under refrigeration (2-4°C). Necropsies were conducted at different time points postmortem (i.e., 0.5 h, 1 h, 4 h, 8 h, 12 h, 24 h, 36 h, 48 h, 7 days and 14 days). Brain sections underwent simultaneous digital evaluation by 14 pathologists until a consensus was reached on terminology, key findings, and intensity levels. Microscopic observations varied among cell types. Glial cells were similarly affected throughout the CNS and showed pericellular halo, chromatin condensation and nuclear shrinkage. Neurons showed two types of postmortem changes as most of them showed progressive shrinkage, cytoplasmic dissolution and karyorrhexis whereas others acquired a dark-neuron-like appearance. Neuronal changes showed marked differences among neuroanatomical locations. Additional postmortem changes encompassed: granulation and microcavitation in neuropil and white matter; retraction spaces; detachment of ependyma, choroid plexus, and leptomeninges. Severity of findings after 48 h at room temperature was higher than after seven days under refrigeration and similar to or slightly lower than after 14 days under refrigeration. No clear differences were observed related to the sex or weight of the animals or their exsanguination status. This work elucidates the onset and progression of autolytic changes in the brains of Wistar Han rats, offering insights to accurately identify and enhance the histopathological evaluation.
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Reproductive failure in dogs is often due to unknown causes, and correct diagnosis and treatment are not always achieved. This condition is associated with various congenital and acquired etiologies that develop inflammatory processes, causing an increase in the number of leukocytes within the female reproductive tract (FRT). An encounter between polymorphonuclear neutrophils (PMNs) and infectious agents or inflammation in the FRT could trigger neutrophil extracellular traps (NETs), which are associated with significantly decreased motility and damage to sperm functional parameters in other species, including humans. This study describes the interaction between canine PMNs and spermatozoa and characterizes the release of NETs, in addition to evaluating the consequences of these structures on canine sperm function. To identify and visualize NETs, May-Grünwald Giemsa staining and immunofluorescence for neutrophil elastase (NE) were performed on canine semen samples and sperm/PMN co-cultures. Sperm viability was assessed using SYBR/PI and acrosome integrity was assessed using PNA-FITC/PI by flow cytometry. The results demonstrate NETs release in native semen samples and PMN/sperm co-cultures. In addition, NETs negatively affect canine sperm function parameters. This is the first report on the ability of NETs to efficiently entrap canine spermatozoa, and to provide additional data on the adverse effects of NETs on male gametes. Therefore, NETs formation should be considered in future studies of canine reproductive failure, as these extracellular fibers and NET-derived pro-inflammatory capacities will impede proper oocyte fertilization and embryo implantation. These data will serve as a basis to explain certain reproductive failures of dogs and provide new information about triggers and molecules involved in adverse effects of NETosis for domestic pet animals.
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Armadilhas Extracelulares , Neutrófilos , Espermatozoides , Animais , Cães , Armadilhas Extracelulares/metabolismo , Masculino , Espermatozoides/metabolismo , Neutrófilos/metabolismo , Motilidade dos Espermatozoides , Feminino , Elastase de Leucócito/metabolismo , Técnicas de Cocultura , Acrossomo/metabolismoRESUMO
OBJECTIVES: For children with intractable functional constipation (FC), there are no evidence-based guidelines for subsequent evaluation and treatment. Our objective was to assess the practice patterns of a large, international cohort of pediatric gastroenterologists. METHODS: We administered a survey to physicians who attended the 2nd World Congress of Pediatric Neurogastroenterology and Motility held in Columbus, Ohio (USA) in September 2023. The survey included 29 questions on diagnostic testing, nonpharmacological and pharmacological treatment, and surgical options for children with intractable FC. RESULTS: Ninety physicians from 18 countries completed the survey. For children with intractable FC, anorectal manometry was the most commonly used diagnostic test. North American responders were more likely than Europeans to use stimulant laxatives (97% vs. 77%, p = 0.032), prosecretory medications (69% vs. 8%, p < 0.001), and antegrade continence enemas (ACE; 83% vs. 46%, p = 0.009) for management. Europeans were more likely than North Americans to require colonic transit testing before surgery (85% vs. 30%, p < 0.001). We found major differences in management practices between Americans and the rest of the world, including use of prosecretory drugs (73% vs. 7%, p < 0.001), anal botulinum toxin injections (81% vs. 58%, p = 0.018), ACE (81% vs. 58% p = 0.018), diverting ileostomies (56% vs. 26%, p = 0.006), and colonic resections (42% vs. 16%, p = 0.012). No differences were found when respondents were compared by years of experience. CONCLUSIONS: Practice patterns in the evaluation and treatment of children with intractable FC differ widely among pediatric gastroenterologists from around the world. A clinical guideline regarding diagnostic testing and surgical decision-making is needed.
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Constipação Intestinal , Padrões de Prática Médica , Humanos , Constipação Intestinal/terapia , Constipação Intestinal/diagnóstico , Padrões de Prática Médica/estatística & dados numéricos , Criança , Laxantes/uso terapêutico , Inquéritos e Questionários , Manometria/estatística & dados numéricos , Feminino , Masculino , Gastroenterologia/estatística & dados numéricosRESUMO
In medicine, ovarian tissue cryopreservation exists for fertility preservation of cancer patients. In fact, ovarian tissue frozen for subsequent thawing and re-transplantation can be contaminated with cancer cells. Therefore, investigations on the effect of cryopreservation on the post-thawed viability of such cells are relevant. Speed of warming is a key parameter of cell cryopreservation. However, the data about comparative viability of cancer cells cryopreserved with different parameters of warming are limited. The aim of our investigations was to assess the malignancy of cryopreserved cancer cells after conventional cooling followed by relatively slow and quick speed of warming. In vitro cultured breast cancer cells of lines ZR-75-1 and MD0MD-231 in form of compacted fragments (as a model of solid tumors) were frozen following a protocol usually used for freezing of ovarian tissue (6 % ethylene glycol+6 % glycerol+0.15 M sucrose, -0.3 °C/min). Cells were warmed by two routine regimes of warming: at 37 °C ("slow" warming) and 100 °C ("quick" warming). Biological properties of cells were investigated: viability, proliferation rate, 2D- and 3D-migration, transmembrane movement and invasion. Quick warming at 100 °C in comparison with slow warming at 37 °C exhibited significantly higher cell survival for MDA-MB-231 cells: 70.1 % vs. 63.2 % and for ZR-75-1 86.8 % vs. 82.9 %, respectively. The cell motility including 2D movement and 3D transmembrane migration were higher after quick thawing at 100 °C. Invasive abilities of cells after cryopreservation were higher than that of fresh (non-treated cells). Both thawing regimes showed a similar rate of cell proliferation. Cryopreservation procedures, and especially this one with quick thawing, increase malignancy of ZR-75-1 and MDA-MB-231 breast cancer cells and risk of metastasis.
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COVID-19 , Hemofilia A , Humanos , COVID-19/complicações , COVID-19/diagnóstico , Hemofilia A/complicações , SARS-CoV-2RESUMO
Background/Purpose: Polycystic ovary syndrome (PCOS) is an endocrine-metabolic disease most common in patients of childbearing age. This pathology is associated with clinical, metabolic, and reproductive complications. We evaluated the diversity of the vaginal microbiota (VM), the vaginal inflammatory reaction (VIR), the proinflammatory state, and the activation of polymorphonuclear neutrophils (PMN) with the production of neutrophil extracellular traps (NETs). Methods: Thirty-three patients who attended a consultation at the Hospital UTPL-Santa Inés, Loja, Ecuador, from May to August 2023 who were diagnosed with PCOS participated in this study. Blood samples, vaginal discharge, and a survey were obtained. Results: A high number of patients, 23/33 (69.7%), presented altered microbiota in clinical variables associated with PCOS phenotypes A and B, sexual partners (>2), and oligomenorrhoea. A significant statistical association was only observed for sexually transmitted infections at sampling (p = 0.023) and insulin (p = 0.002). All eight cases studied with VIR had PMN/NETotic activity. A high frequency of proinflammatory states was observed in all vaginal microbiota states. Conclusions: These results suggest that the PCOS could trigger a proinflammatory state in the vaginal epithelium independently of the state of the vaginal microbiota. Furthermore, the presence of NETs observed in the cases studied could decrease fertility in these PCOS patients.
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Background: Polycystic ovary syndrome (PCOS) is a highly prevalent endocrine-metabolic disorder in women of reproductive age. Diagnosis is based on the evidence-based international guideline 2018 and the Rotterdam Consensus to classify PCOS phenotypes. This study aims to characterize the biodemographic, clinical, metabolic, and reproductive variables and their relationship with PCOS phenotypes in a population from the Ecuadorian Andes. Methodology: A cross-sectional study was conducted with a non-random consecutive sample of 92 women who attended the outpatient gynecology and endocrinology clinic at the Hospital of the Technical University of Loja (UTPL)-Santa Inés, Loja, Ecuador, between January 2022 and July 2023. Descriptive statistics, mean calculations, standard deviation, parametric and nonparametric tests, odds ratios (OR), confidence intervals (CI), and p-values were employed. Results: The average age was 22 ± 3.4 years, with a predominantly mestizo, urban, single, highly educated, and medium-high socioeconomic level population. It was identified that phenotypes A + B are at a higher risk of developing oligomenorrhea and hypertriglyceridemia compared to phenotypes C + D, with statistically significant differences (p < 0.05). Furthermore, in terms of reproductive variables, phenotypes A + B exhibit a significantly higher frequency of elevated anti-Müllerian hormone (AMH) compared to phenotypes C + D, also with statistical significance (p < 0.05). Conclusions: The classical phenotypes A and B of PCOS are the most common in Ecuadorian Andean women and carry a higher risk of insulin resistance, anovulation, metabolic disorders, and elevated triglyceride levels compared to phenotypes C and D. Ethnic diversity and sociocultural habits influence the prevalence and clinical manifestations of these phenotypes.
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Cobalt protoporphyrin (CoPP) is a synthetic heme analog that has been observed to reduce food intake and promote sustained weight loss. While the precise mechanisms responsible for these effects remain elusive, earlier research has hinted at the potential involvement of nitric oxide synthase in the hypothalamus. This study aimed to delve into CoPP's impact on the activities of crucial antioxidant enzymes: superoxide dismutase (SOD), catalase, glutathione peroxidase (GPx), glutathione reductase (GR), and glutathione-S-transferase (GST) across seven distinct brain regions (hippocampus, hypothalamus, prefrontal cortex, motor cortex, striatum, midbrain, and cerebellum), as well as in the liver and kidneys. Female Wistar rats weighing 180 to 200 grams received a single subcutaneous dose of 25 µmol/kg CoPP. After six days, brain tissue was extracted to assess the activities of antioxidant enzymes and quantify malondialdehyde levels. Our findings confirm that CoPP administration triggers the characteristic effects of decreased food intake and reduced body weight. Moreover, it led to an increase in SOD activity in the hypothalamus, a pivotal brain region associated with food intake regulation. Notably, CoPP-treated rats exhibited elevated enzymatic activity of catalase, GR, and GST in the motor cortex without concurrent signs of heightened oxidative stress. These results underscore a strong connection between the antioxidant system and food intake regulation. They also emphasize the need for further investigation into the roles of antioxidant enzymes in modulating food intake and the ensuing weight loss, using CoPP as a valuable research tool.
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Antioxidantes , Hipotálamo , Córtex Motor , Protoporfirinas , Animais , Feminino , Ratos , Antioxidantes/metabolismo , Peso Corporal/efeitos dos fármacos , Catalase/metabolismo , Ingestão de Alimentos/efeitos dos fármacos , Glutationa Peroxidase/efeitos dos fármacos , Glutationa Peroxidase/metabolismo , Glutationa Redutase/efeitos dos fármacos , Glutationa Redutase/metabolismo , Glutationa Transferase/efeitos dos fármacos , Glutationa Transferase/metabolismo , Hipotálamo/metabolismo , Hipotálamo/efeitos dos fármacos , Hipotálamo/enzimologia , Malondialdeído/metabolismo , Córtex Motor/efeitos dos fármacos , Córtex Motor/metabolismo , Córtex Motor/enzimologia , Estresse Oxidativo/efeitos dos fármacos , Protoporfirinas/farmacologia , Ratos Wistar , Superóxido Dismutase/efeitos dos fármacos , Superóxido Dismutase/metabolismoRESUMO
Dioxygen binding solely through non-covalent interactions is rare. In living systems, dioxygen transport takes place via iron or copper-containing biological cofactors. Specifically, a reversible covalent interaction is established when O2 binds to the mono or polynuclear metal center. However, O2 stabilization in the absence of covalent bond formation is challenging and rarely observed. Here, we demonstrate a unique example of reversible non-covalent binding of dioxygen within the cavity of a well-defined synthetic all-Cu(i) tetracopper cluster.
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BACKGROUND: Microscopic polyangiitis (MPA) and granulomatosis with polyangiitis (GPA) are the two major antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV). OBJECTIVES: To characterize a homogenous AAV cohort and to assess the impact of clinicopathological profiles and ANCA serotypes on clinical presentation and prognosis. Clinical differences in GPA patients according to ANCA serotype and the diagnostic yield for vasculitis of biopsies in different territories were also investigated. RESULTS: This retrospective study (2000-2021) included 152 patients with AAV (77 MPA/75 GPA). MPA patients (96.1% myeloperoxidase [MPO]-ANCA and 2.6% proteinase 3 [PR3]-ANCA) presented more often with weight loss, myalgia, renal involvement, interstitial lung disease (ILD), cutaneous purpura, and peripheral nerve involvement. Patients with GPA (44% PR3-ANCA, 33.3% MPO, and 22.7% negative/atypical ANCA) presented more commonly with ear, nose, and throat and eye/orbital manifestations, more relapses, and higher survival than patients with MPA. GPA was the only independent risk factor for relapse. Poor survival predictors were older age at diagnosis and peripheral nerve involvement. ANCA serotypes differentiated clinical features in a lesser degree than clinical phenotypes. A mean of 1.5 biopsies were performed in 93.4% of patients in different territories. Overall, vasculitis was identified in 80.3% (97.3% in MPA and 61.8% in GPA) of patients. CONCLUSIONS: The identification of GPA presentations associated with MPO-ANCA and awareness of risk factors for relapse and mortality are important to guide proper therapeutic strategies in AAV patients. Biopsies of different affected territories should be pursued in difficult-to-diagnose patients based on their significant diagnostic yield.
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Vasculite Associada a Anticorpo Anticitoplasma de Neutrófilos , Granulomatose com Poliangiite , Poliangiite Microscópica , Humanos , Granulomatose com Poliangiite/diagnóstico , Granulomatose com Poliangiite/complicações , Granulomatose com Poliangiite/tratamento farmacológico , Poliangiite Microscópica/diagnóstico , Poliangiite Microscópica/complicações , Anticorpos Anticitoplasma de Neutrófilos/uso terapêutico , Estudos Retrospectivos , Vasculite Associada a Anticorpo Anticitoplasma de Neutrófilos/diagnóstico , Vasculite Associada a Anticorpo Anticitoplasma de Neutrófilos/complicações , Mieloblastina , RecidivaRESUMO
BACKGROUND: Severe acute syndrome coronavirus 2 can invade a variety of tissues, including the testis. Even though this virus is scarcely found in human semen polymerase chain reaction tests, autopsy studies confirm the viral presence in all testicular cell types, including spermatozoa and spermatids. OBJECTIVE: To investigate whether the severe acute syndrome coronavirus 2 is present inside the spermatozoa of negative polymerase chain reaction-infected men up to 3 months after hospital discharge. MATERIALS AND METHODS: This cross-sectional study included 13 confirmed moderate-to-severe COVID-19 patients enrolled 30-90 days after the diagnosis. Semen samples were obtained and examined with real-time polymerase chain reaction for RNA detection and by transmission electron microscopy. RESULTS: In moderate-to-severe clinical scenarios, we identified the severe acute syndrome coronavirus 2 inside spermatozoa in nine of 13 patients up to 90 days after discharge from the hospital. Moreover, some DNA-based extracellular traps were reported in all studied specimens. DISCUSSION AND CONCLUSION: Although severe acute syndrome coronavirus 2 was not present in the infected men's semen, it was intracellularly present in the spermatozoa till 3 months after hospital discharge. The Electron microscopy (EM) findings also suggest that spermatozoa produce nuclear DNA-based extracellular traps, probably in a cell-free DNA-dependent manner, similar to those previously described in the systemic inflammatory response to COVID-19. In moderate-to-severe cases, the blood-testes barrier grants little defence against different pathogenic viruses, including the severe acute syndrome coronavirus 2. The virus could also use the epididymis as a post-testicular route to bind and fuse to the mature spermatozoon and possibly accomplish the reverse transcription of the single-stranded viral RNA into proviral DNA. These mechanisms can elicit extracellular cell-free DNA formation. The potential implications of our findings for assisted conception must be addressed, and the evolutionary history of DNA-based extracellular traps as preserved ammunition in animals' innate defence might improve our understanding of the severe acute syndrome coronavirus 2 pathophysiology in the testis and spermatozoa.
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The energy crisis and climate change are two of the most concerning issues for human beings nowadays. For that reason, the scientific community is focused on the search for alternative biofuels to conventional fossil fuels as well as the development of sustainable processes to develop a circular economy. Bioelectrochemical processes have been demonstrated to be useful for producing bioenergy and value-added products from several types of waste. Electro-fermentation has gained great attention in the last few years due to its potential contribution to biofuel and biochemical production, e.g., hydrogen, methane, biopolymers, etc. Conventional fermentation processes pose several limitations in terms of their practical and economic feasibility. The introduction of two electrodes in a bioreactor allows the regulation of redox instabilities that occur in conventional fermentation, boosting the overall process towards a high biomass yield and enhanced product formation. In this regard, key parameters such as the type of culture, the nature of the electrodes as well as the operating conditions are crucial in order to maximize the production of biofuels and biochemicals via electro-fermentation technology. This article comprises a critical overview of the benefits and limitations of this emerging bio-electrochemical technology and its contribution to the circular economy.
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Biocombustíveis , Reatores Biológicos , Humanos , Fermentação , Biomassa , HidrogênioRESUMO
Non-thermal plasmas (NTPs), known as cold atmospheric plasmas (CAPs), hold great potential for diverse medical applications, including dentistry. However, traditional linear and rigid dielectric barrier discharge reactors used for NTP generation encounter limitations in accessing oral cavities and root canals. To address this issue, we have developed an innovative NTP reactor featuring an angled end for improved accessibility. The central copper electrode, with a 0.59 mm diameter and adjustable length for desired angulation, is coated with zircon powder (ZrSiO4) to ensure stable NTP generation. This central electrode is housed within a stainless steel tube (3 mm internal diameter, 8 mm external diameter, and 100 mm length) with a 27° angle at one end, making it ergonomically suitable for oral applications. NTP generation involves polarizing the reactor electrodes with 13.56 MHz radio frequency signals, using helium gas as a working medium. We introduce plasma-treated water (PTW) as an adjunctive therapy to enhance biofilm eradication within root canals. A synergistic approach combining NTP and PTW is employed and compared to the gold standard (sodium hypochlorite, NaOCl), effectively neutralizing Enterococcus faecalis bacteria, even in scenarios involving biofilms. Moreover, applying NTP in both gaseous and liquid environments successfully achieves bacterial inactivation at varying treatment durations, demonstrating the device's suitability for medical use in treating root canal biofilms. The proposed NTP reactor, characterized by its innovative design, offers a practical and specific approach to plasma treatment in dental applications. It holds promise in combatting bacterial infections in root canals and oral cavities.