Early High-Titer Plasma Therapy to Prevent Severe Covid-19 in Older Adults.

BACKGROUND: Therapies to interrupt the progression of early coronavirus disease 2019 (Covid-19) remain elusive. Among them, convalescent plasma administered to hospitalized patients has been unsuccessful, perhaps because antibodies should be administered earlier in the course of illness. METHODS: We conducted a randomized, double-blind, placebo-controlled trial of convalescent plasma with high IgG titers against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in older adult patients within 72 hours after the onset of mild Covid-19 symptoms. The primary end point was severe respiratory disease, defined as a respiratory rate of 30 breaths per minute or more, an oxygen saturation of less than 93% while the patient was breathing ambient air, or both. The trial was stopped early at 76% of its projected sample size because cases of Covid-19 in the trial region decreased considerably and steady enrollment of trial patients became virtually impossible. RESULTS: A total of 160 patients underwent randomization. In the intention-to-treat population, severe respiratory disease developed in 13 of 80 patients (16%) who received convalescent plasma and 25 of 80 patients (31%) who received placebo (relative risk, 0.52; 95% confidence interval [CI], 0.29 to 0.94; P = 0.03), with a relative risk reduction of 48%. A modified intention-to-treat analysis that excluded 6 patients who had a primary end-point event before infusion of convalescent plasma or placebo showed a larger effect size (relative risk, 0.40; 95% CI, 0.20 to 0.81). No solicited adverse events were observed. CONCLUSIONS: Early administration of high-titer convalescent plasma against SARS-CoV-2 to mildly ill infected older adults reduced the progression of Covid-19. (Funded by the Bill and Melinda Gates Foundation and the Fundación INFANT Pandemic Fund; Dirección de Sangre y Medicina Transfusional del Ministerio de Salud number, PAEPCC19, Plataforma de Registro Informatizado de Investigaciones en Salud number, 1421, and ClinicalTrials.gov number, NCT04479163.).

Effect of Thiazolidin-4-one Against Lipopolysaccharide-Induced Oxidative Damage, and Alterations in Adenine Nucleotide Hydrolysis and Acetylcholinesterase Activity in Cultured Astrocytes.

Astrocytes play multiple important roles in brain physiology. However, depending on the stimuli, astrocytes may exacerbate inflammatory reactions, contributing to the development and progression of neurological diseases. Therefore, therapies targeting astrocytes represent a promising area for the development of new brain drugs. Thiazolidinones are heterocyclic compounds that have a sulfur and nitrogen atom and a carbonyl group in the ring and represent a class of compounds of great scientific interest due to their pharmacological properties. The aim of this study was to investigate the effect of 3-(3-(diethylamino)propyl)-2-(4-(methylthio)phenyl)thiazolidin-4-one (DS27) on cell proliferation and morphology, oxidative stress parameters, activity of the enzymes ectonucleotidases and acetylcholinesterase (AChE) and interleukin 6 (IL-6) levels in primary astrocyte cultures treated with lipopolysaccharide (LPS), to model neuroinflammation. The astrocyte culture was exposed to LPS (10 µg/ml) for 3 h and subsequently treated with compound DS27 for 24 and 48 h (concentrations ranging to 10-100 µM). LPS induced an increase in astrocyte proliferation, AChE activity, IL-6 levels, oxidative damage, ATP and ADP and a reduction in AMP hydrolysis in rat primary astrocyte cultures. DS27 treatment was effective in reversing these alterations induced by LPS. Our findings demonstrated that DS27 is able to modulate cholinergic and purinergic signaling, redox status, and the levels of pro-inflammatory cytokines in LPS-induced astrocyte damage. These glioprotective effects of DS27 may be very important for improving neuroinflammation, which is associated with many brain diseases.

Tannic Acid Attenuates Peripheral and Brain Changes in a Preclinical Rat Model of Glioblastoma by Modulating Oxidative Stress and Purinergic Signaling.

Glioblastoma (GB) is a highly aggressive and invasive brain tumor; its treatment remains palliative. Tannic acid (TA) is a polyphenol widely found in foods and possesses antitumor and neuroprotective activities. This study aimed to investigate the effect of TA on oxidative stress parameters and the activity of ectonucleotidases in the serum, platelets, and lymphocytes and/or in the brain of rats with preclinical GB. Rats with GB were treated intragastrically with TA (50 mg/kg/day) for 15 days or with a vehicle. In the platelets of the animals with glioma, the adenosine triphosphate (ATP) and adenosine monophosphate (AMP) hydrolysis and the catalase (CAT) activity decreased. Besides, the adenosine diphosphate (ADP) hydrolysis, adenosine (Ado) deamination, and the reactive oxygen species (ROS) and nitrite levels were increased in glioma animals; however, TA reversed ROS and nitrite levels and AMP hydrolysis alterations. In lymphocytes from animals with glioma, the ATP and ADP hydrolysis, as well as Ado deamination were increased; TA treatment countered this increase. In the brain of the animals with glioma, the ROS, nitrite, and thiobarbituric acid reactive substance (TBARS) levels increased and the thiol (SH) levels and CAT and superoxide dismutase (SOD) activities were decreased; TA treatment decreased the ROS and TBARS levels and restored the SOD activity. In the serum of the animals with glioma, the ATP hydrolysis decreased; TA treatment restored this parameter. Additionally, the ROS levels increased and the SH and SOD activity decreased by glioma implant; TA treatment enhanced nitrite levels and reversed SOD activity. Altogether, our results suggest that TA is an important target in the treatment of GB, as it modulates purinergic and redox systems.

Blueberry extract as a potential pharmacological tool for preventing depressive-like behavior and neurochemical dysfunctions in mice exposed to lipopolysaccharide.

OBJECTIVE: Major depressive disorder is a debilitating and recurrent psychiatric disorder. Blueberries have several biological properties, including neuroprotective effects, through antioxidant and anti-inflammatory actions. The aim of this study was to evaluate the effect of blueberry extract on depressive-like behavior and lipopolysaccharide (LPS)-induced neurochemical changes. METHODS: Mice were pretreated with vehicle, fluoxetine (20 mg/kg) or blueberry extract (100 or 200 mg/kg) intragastrically for seven days before intraperitoneal LPS (0.83 mg/kg) injection. Twenty-four hours after LPS administration, mice were submitted to behavioral tests. Oxidative stress and neuroinflammatory parameters were evaluated in the cerebral cortex, hippocampus, and striatum. RESULTS: Our data showed that blueberry extract or fluoxetine treatment protected against LPS-induced depressive-like behavior in tail suspension and splash tests (P < 0.05), without changes in locomotor activity (P > 0.05). LPS induced an increase in the levels of reactive oxygen species (P < 0.001), nitrite (P < 0.05) and thiobarbituric acid reactive substances (P < 0.01), as well as a reduction in total sulfhydryl content (P < 0.05) and catalase activity (P < 0.05) in brain structures; blueberry extract restored these alterations (P < 0.05). In addition, blueberry extract attenuated the increase in tumor necrosis factor-alpha (TNF-α) levels induced by LPS administration (P < 0.05). CONCLUSION: This study showed that blueberry extract exerted antidepressant-like effects, protected the brain against oxidative damage, and modulated TNF-α levels induced by LPS.

Selective in vitro anticancer effect of blueberry extract (Vaccinium virgatum) against C6 rat glioma: exploring their redox status.

The aim of this study was to investigate the anticancer potential of blueberry extract (Vaccinium virgatum) against a C6 rat glioma lineage. Cultures of the C6 cells were exposed to blueberry extract at concentrations of 50 to 600 µg/mL for 12, 24, 48, or 72 h and then evaluated for cell viability, proliferation, migration, colony formation and oxidative stress. We also evaluated the effects of blueberry extract on primary rat cortical astrocytes. Our results show that treatment with blueberry extract did not alter the viability or proliferation of normal primary astrocytes but it did significantly reduce the viability in 21.54 % after 48 h and proliferation in 8.59 % after 24 h of C6 cells at 200 µg/mL. We also observed a reduction in the size of the colonies of 29.99 % at 100 µg/mL when compared to the control cells and cell migration was also reduced at 50 µg/mL. After 72 h, there was a reduction in the reactive oxygen species levels ranging from 46.26 to 34.73 %, in addition to a 380.2 % increase in total thiol content. Superoxide dismutase, catalase, and glutathione S-transferase activities were also enhanced when compared to the control. Taken together this data suggests that blueberry extract exerts some selective anticancer activity in C6 glioma cells.

Senolytics prevent age-associated changes in female mice brain.

PURPOSE: Considering that the combination of dasatinib and quercetin (D + Q) demonstrated a neuroprotective action, as well as that females experience a decline in hormonal levels during aging and this is linked to increased susceptibility to Alzheimer's disease, in this study we evaluated the effect of D + Q on inflammatory and oxidative stress markers and on acetylcholinesterase and Na+, K+-ATPase activities in brain of female mice. METHODS: Female C57BL/6 mice were divided in Control and D (5 mg/kg) + Q (50 mg/kg) treated. Treatment was administered via gavage for three consecutive days every two weeks starting at 30 days of age. The animals were euthanized at 6 months of age and at 14 months of age. RESULTS: Results indicate an increase in reactive species (RS), thiol content and lipid peroxidation followed by a reduction in nitrite levels and superoxide dismutase, catalase and glutathione S-transferase activity in the brain of control animals with age. D+Q protected against age-associated increase in RS and catalase activity reduction. Acetylcholinesterase activity was increased, while Na+, K+-ATPase activity was reduced at 14 months of age and D+Q prevented this reduction. CONCLUSION: These data demonstrate that D+Q can protect against age-associated neurochemical alterations in the female brain.

Effect of blueberry (Vaccinium virgatum) extract on depressive-like behavior and metabolic serum alterations in lipopolysaccharide-challenged mice.

In the present study, we aimed to investigate the protective effect of blueberry extract on behavioral, biochemical, and morphological changes in an experimental model of lipopolysaccharide (LPS)-induced depressive behavior. Male Swiss mice were pretreated with the vehicle, fluoxetine (20 mg/kg), or Vaccinium virgatum extract (100 mg/kg and 200 mg/kg) for seven days. On day 7, the animals were administered an LPS injection (0.83 mg/kg) or vehicle. Pretreatment with blueberry extract prevented LPS-induced depressive-like behavior. Moreover, LPS increased serum levels of total cholesterol; however, V. virgatum did not prevent the increase in total cholesterol levels. Furthermore, the extract prevented the LPS-induced elevation in serum reactive oxygen species. Also, V. virgatum extract increased the HDL cholesterol levels. Additionally, this extract prevented the LPS-induced decrease in glucose levels and serum adenosine deaminase activity. Collectively, V. virgatum extract has a potential protective effect against changes similar to those observed in patients with depression. PRACTICAL APPLICATIONS: Vaccinium virgatum, popularly known as blueberry, has been effective in preventing or treating neuropsychiatric diseases owing to its antioxidant, anti-inflammatory, and neuroprotective properties. Fluoxetine is a known drug used to treat depression; however, its adverse effects result in therapeutic non-adherence. Thus, the search for new natural compounds possessing antidepressant activities while lacking adverse effects is crucial for identifying novel therapeutic alternatives against depression.

Juvenile xanthogranuloma of the cauda equina.

Juvenile xanthogranuloma is a form of histiocytic proliferative disorder that usually affects the skin and tends to occur during infancy. On rare occasions, it has been reported at extracutaneous sites and in other age groups. Isolated juvenile xanthogranuloma of the nervous system is extremely rare, especially in the cauda equina. A case of juvenile xanthogranuloma of the cauda equina in a 14-year-old boy is reported, and the literature is reviewed.

Pleural antigen assay in the diagnosis of pediatric pneumococcal empyema.

PURPOSE: The purpose of the study was to assess the diagnostic value of rapid pneumococcal antigen detection (PAD) in pleural fluid samples of children with empyema. MATERIAL AND METHODS: We performed a prospective evaluation in a pediatric intensive care unit of a tertiary university hospital of children aged 1 month to 14 years admitted with empyema. Standard cultures (conventional microbiological culture [CMC]), PAD by immunochromatographic testing (Binax NOW Streptococcus pneumoniae; Binax, Portland, ME), and/or real-time polymerase chain reactions (RTPs) on pleural samples were performed in all included patients. RESULTS: Fifty-five cases with a mean (SD) age of 6.5 (6.1) years were enrolled. Streptococcus pneumoniae was identified in 28 cases (51%): by CMC in 15 cases and by RTP in a further 13 cases. Using CMC and/or RTP as the criterion standard, PAD showed a sensitivity of 96% (95% confidence interval, 86%-100%), a specificity of 100% (75%-100%), a positive predictive value of 100% (98%-100%), and a Youden index of 0.96 (0.88-1.04). CONCLUSIONS: Pneumococcal antigen detection in pleural fluid specimens from children provides a rapid, simple, sensitive, and reliable method of diagnosis for pneumococcal empyema at bedside.