Background: Risk factors for developing long COVID are not clearly established. The present study was designed to determine if any sign, symptom, or treatment of the acute phase, or personal characteristics of the patient, is associated with the development of long COVID. Methods: A cohort study was carried out, randomly selecting symptomatic COVID-19 patients and not vaccinated. The severity of the acute illness was assessed through the number of compatible COVID-19 symptoms, hospitalizations, and the symptom severity score using a 10-point visual analog scale. Results: After multivariate analysis, a severity score ≥8 (RR 2.0, 95%CI 1.1–3.5, p = 0.022), hospitalization (RR 2.1, 95%CI 1.0–4.4, p = 0.039), myalgia (RR 1.9, 95%CI 1.08–3.6, p = 0.027), tachycardia (RR 10.4, 95%CI 2.2–47.7, p = 0.003), and use of antibiotics (RR 2.0, 95%CI 1.1–3.5, p = 0.022), was positively associated with the risk of having long COVID. Higher levels of education (RR 0.6, 95%CI 0.4–0.9, p = 0.029) and type positive B blood group (B + AB, RR 0.44, 95%CI 0.2–0.9, p = 0.044) were protective factors. The most important population attributable fractions (PAFs) for long COVID were myalgia (37%), severity score ≥8 (31%), and use of antibiotics (27%). Conclusions: Further studies in diverse populations over time are needed to expand the knowledge that could lead us to prevent and/or treat long COVID.

Coronavirus disease 2019 (COVID‑19) is currently the major public health problem worldwide. Neutral electrolyzed saline solution that contains reactive chlorine and oxygen species may be an effective therapeutic. In the present study, the treatment efficacy of intravenous and/or nebulized neutral electrolyzed saline combined with usual medical care vs. usual medical care alone was evaluated in ambulatory patients with COVID‑19. A prospective, 2‑arm, parallel‑group, randomized, open‑label, multi‑center, phase I‑II clinical trial including 214 patients was performed. The following two outcomes were evaluated during the 20‑day follow‑up: i) The number of patients with disease progression; and ii) the patient acceptable symptom state. Serial severe acute respiratory syndrome coronavirus 2 naso/oro‑pharyngeal detection by reverse transcription‑quantitative (RT‑q) PCR was performed in certain patients of the experimental group. Biochemical and hematologic parameters, as well as adverse effects, were also evaluated in the experimental group. The experimental treatment decreased the risk of hospitalization by 89% [adjusted relative risk (RR)=0.11, 95% confidence interval (CI): 0.03‑0.37, P<0.001] and the risk of death by 96% (adjusted RR=0.04, 95% CI: 0.01‑0.42, P=0.007) and also resulted in an 18‑fold higher probability of achieving an acceptable symptom state on day 5 (adjusted RR=18.14, 95% CI: 7.29‑45.09, P50% were negative for the virus as detected by RT‑qPCR in naso/oro‑pharyngeal samples on day 4, with only a small number of positive patients on day 6. Clinical improvement correlated with a decrease in C‑reactive protein, aberrant monocytes and increased lymphocytes and platelets. Cortisol and testosterone levels were also evaluated and a decrease in cortisol levels and an increase in the testosterone‑cortisol ratio were observed on days 2 and 4. The experimental treatment produced no serious adverse effects. In conclusion, neutral electrolyzed saline solution markedly reduced the symptomatology and risk of progression in ambulatory patients with COVID‑19. The present clinical trial was registered in the Cuban public registry of clinical trials (RPCEC) database (May 5, 2020; no. TX‑COVID19: RPCEC00000309).

Objective: This study aimed to examine the effects of moderate (MIT) and high-intensity training (HIT) chronic exercise on plasma tumor necrosis factor alpha (TNF-alpha) level and its impact on Langerhans islet morphology in healthy rats. Methods: Two-month old normal male Wistar rats were divided into three groups: control (C, n= 6), MIT (n= 6), and HIT (n= 4). The training protocol consisted in 24 sessions of running on a treadmill at 60-80% maximal oxygen consumption (VO2max) for MIT, and >80% VO2max for HIT. TNF-alpha and insulin were measured with ELISA tests. Duodenal pancreas was dissected to analyze the Langerhans islets by immunohistochemistry, a correlation analysis was performed with the nuclei/total islet area. Results: HIT and MIT rats showed lower TNF-alpha plasma levels than controls. Plasma insulin level decreased significantly in HIT compared with C and MIT. In addition, the islet area and nuclei density per islet were higher in the exercise groups compared with C. However, none of the groups showed PD1 immunoreactivity. Conclusions: Under healthy conditions, the chronic exercise reduced plasmatic TNF-alpha level, and in the same sense, increased the size of the Langerhans islets, depending to the exercise intensity.

Prostate cancer (PCa) is the second most common non‑dermatological cancer in men and is a growing public health problem. Castration‑resistant disease (CRD) is the most advanced stage of the disease and is difficult to control. Patients with CRD may no longer accept conventional therapies as they are not in appropriate clinical conditions or they refuse to receive it. Given that inflammation is an essential component of CRD origin and progression, anti‑inflammatory agents could be a therapeutic option with fenamates as one of the proposed choices. A prospective, randomized, double‑blinded, 2‑arm, parallel group, phase II‑III clinical trial was performed involving 20 patients with CRD‑PCa (with a prostate specific antigen level <100 ng/ml) that were undergoing androgen deprivation therapy (ADT) and did not accept any established treatment for that disease stage. In addition to ADT, 10 patients received placebo and 10 received mefenamic acid (500 mg orally every 12 h) for 6 months. The primary endpoint was the change in serum prostate‑specific antigen (PSA) at 6 months. The PSA levels decreased significantly with mefenamic acid (an average 42% decrease), whereas there was an average 55% increase in the placebo group (P=0.024). In the patients treated with the placebo, 70% had biochemical disease progression (an increase of ≥25% in PSA levels), which did not occur in any of the patients treated with mefenamic acid (relative risk=0.12; 95% confidence interval, 0.01‑0.85; P=0.033). There was a significant increase in quality of life (EQ‑5D‑5L score) and body mass index (BMI) with the experimental treatment. In conclusion, mefenamic acid administration decreased biochemical progression in patients with castration resistant PCa, improved their quality of life and increased their BMI. Future studies are required in order to strengthen the findings of the present clinical trial. Trial registration, Cuban Public Registry of Clinical Trials Database RPCEC00000248, August 2017.

COVID-19 vaccines primarily prevent severe illnesses or hospitalization, but there is limited data on their impact during hospitalization for seriously ill patients. In a Mexican cohort with high COVID-19 mortality, a study assessed vaccination’s effects. From 2021 to 2022, 462 patients with 4455 hospital days were analyzed. The generalized multivariate linear mixed model (GENLINMIXED) with binary logistic regression link, survival analysis and ROC curves were used to identify risk factors for death. The results showed that the vaccinated individuals were almost half as likely to die (adRR = 0.54, 95% CI = 0.30–0.97, p = 0.041). When stratifying by vaccine, the Pfizer group (BNT162b2) had a 2.4-times lower risk of death (adRR = 0.41, 95% CI = 0.2–0.8, p = 0.008), while the AstraZeneca group (ChAdOx1-S) group did not significantly differ from the non-vaccinated (adRR = 1.04, 95% CI = 0.5–2.3, p = 0.915). The Pfizer group exhibited a higher survival, the unvaccinated showed increasing mortality, and the AstraZeneca group remained intermediate (p = 0.003, multigroup log-rank test). Additionally, BNT162b2-vaccinated individuals had lower values for markers, such as ferritin and D-dimer. Biochemical and hematological indicators suggested a protective effect of both types of vaccines, possibly linked to higher lymphocyte counts and lower platelet-to-lymphocyte ratio (PLR). It is imperative to highlight that these results reinforce the efficacy of COVID-19 vaccines. However, further studies are warranted for a comprehensive understanding of these findings.

Dengue mortality has traditionally been associated with severe thrombocytopenia and hemorrhagic complications. However, during 2024, dengue virus serotype 3 (DENV-3) increased significantly in western Mexico, leading to the emergence of a distinct clinical pattern. We conducted a retrospective cohort study of hospitalized dengue patients at the General Hospital of Colima (January–August 2024). Clinical features, laboratory parameters, and outcomes were compared between survivors and non-survivors. Among 201 hospitalized patients, 6 (3.0%) died. All deceased patients presented with generalized seizures, polyserositis (pleural effusion and/or ascites), and required mechanical ventilation. Contrary to classical patterns, they did not have severe thrombocytopenia. Instead, they showed significantly higher white blood cell counts and notably increased levels of serum urea and BUN, suggesting early renal impairment. ROC analysis indicated that BUN (AUC 0.904) and urea (AUC 0.906) were good to excellent discriminators of mortality. During 2024, with an increase in DENV-3 circulation, mortality was associated with neurological and systemic complications, including seizures and polyserositis, as well as biochemical evidence of renal dysfunction—but not with severe thrombocytopenia. These findings challenge current paradigms and highlight the need for early recognition of atypical clinical patterns.