Pentoxifylline: A Drug with Antiviral and Anti-Inflammatory Effects to Be Considered in the Treatment of Coronavirus Disease 2019

In December 2019, a new coronavirus, named severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), emerged from China, causing pneumonia outbreaks first in the Wuhan region and has now spread worldwide. There are no specific drugs for the disease caused by this virus, coronavirus disease 2019 (COVID-19). Considering that new synthesized drugs cannot be applied immediately to patients, conventional drug in new use is a feasible solution. Chloroquine, remdesivir, favipiravir, lopinavir, ribavirin, and ritonavir have shown efficacy to inhibit coronavirus in vitro. Pentoxifylline, a drug with anti-inflammatory, immunomodulatory, and bronchodilatory effects, has previously been shown to inhibit several viral infections. Immunological studies have shown that most patients with severe COVID-19 exhibit substantially elevated serum levels of pro-inflammatory cytokines. Pentoxifylline is a phosphodiesterase inhibitor that increases the levels of cyclic adenosine monophosphate, which in turn activates protein kinase, leading to a reduction in the synthesis of pro-inflammatory cytokines and immune cell migration. Here, we propose pentoxifylline, a drug with low cost and toxicity, as a possible treatment for COVID-19 based on its interesting properties.     

Amygdala-prefrontal cortical circuitry regulates effort-based decision making

The basolateral amygdala (BLA) and the anterior cingulate cortex (ACC) region of the prefrontal cortex form an interconnected neural circuit that may mediate certain types of decision-making processes. The present study assessed the role of this pathway in effort-based decision making using a cost-benefit T-maze task. Rats were given a choice of obtaining a high reward by climbing a 30-cm barrier in 1 arm (4 pellets; high-reward [HR] arm) or a small reward in the other arm with no barrier (2 pellets; low-reward [LR] arm). In Experiment 1, bilateral inactivation of the BLA via infusion of bupivacaine impaired decision making, reducing the preference for the HR arm. This effect was not due to spatial or motor deficits because BLA inactivation did not alter behavior when the amount of effort required to obtain either reward was equalized by placing a 2nd barrier in the LR arm. In Experiment 2, disconnection between the BLA and ACC, entailing a unilateral BLA inactivation combined with a contralateral ACC inactivation also impaired decision making. These data suggest that the serial transfer of information between the BLA and ACC guides response selection when evaluating the value of an expected outcome relative to the costs of performing a particular action.     

Relationship between glycated hemoglobin,Intensive Care Unit admission blood sugar and glucose control with ICU mortality in critically ill patients

Background and Aims:

The association between hyperglycemia and mortality is believed to be influenced by the presence of diabetes mellitus (DM). In this study, we evaluated the effect of preexisting hyperglycemia on the association between acute blood glucose management and mortality in critically ill patients. The primary objective of the study was the relationship between HbA₁c and mortality in critically ill patients. Secondary objectives of the study were relationship between Intensive Care Unit (ICU) admission blood glucose and glucose control during ICU stay with mortality in critically ill patients.

Materials and Methods:

Five hundred patients admitted to two ICUs were enrolled. Blood sugar and hemoglobin A₁c (HbA₁c) concentrations on ICU admission were measured. Age, sex, history of DM, comorbidities, Acute Physiology and Chronic Health Evaluation II score, sequential organ failure assessment score, hypoglycemic episodes, drug history, mortality, and development of acute kidney injury and liver failure were noted for all patients.

Results:

Without considering the history of diabetes, nonsurvivors had significantly higher HbA₁c values compared to survivors (7.25 ± 1.87 vs. 6.05 ± 1.22, respectively, P < 0.001). Blood glucose levels in ICU admission showed a significant correlation with risk of death (P < 0.006, confidence interval [CI]: 1.004–1.02, relative risk [RR]: 1.01). Logistic regression analysis revealed that HbA₁c increased the risk of death; with each increase in HbA₁c level, the risk of death doubled. However, this relationship was not statistically significant (P: 0.161, CI: 0.933–1.58, RR: 1.2).

Conclusions:

Acute hyperglycemia significantly affects mortality in the critically ill patients; this relation is also influenced by chronic hyperglycemia.     

Randomized Comparison of Ranitidine Bismuth Citrate-Based Triple Therapies for Helicobacter pylori

Objectives: In an attempt to increase the efficacy and simplicity of FDA-approved regimens for Helicobacter pylori , we studied (1) addition of an inexpensive antibiotic (amoxicillin) to twice-daily ranitidine bismuth citrate (RBO-clarithromycin dual therapy, and (2) substitution of RBC for bismuth subsalicylate + H2-receptor antagonist in bismuth-based triple therapy. Methods : Subjects with previously untreated Helicobacter pylori infection documented by ¹³C-urea breath test plus either endoscopic biopsy or serology were randomly assigned to a 2-wk course of (1) RBC 400 mg b.i.d. , amoxicillin 1 g b.i.d. , and clarithromycin 500 mg b.i.d. (RAC), or (2) RBC 400 mg b.i.d. , metronidazole 250 mg t.i.d. , and tetracycline 500 mg t.i.d. (RMT). Repeat breath test was performed 4 wk after the completion of therapy. Results : Intent-to-treat and per-protocol cure rates for RAC were 46 of 50 patients (92%) and 45 of 47 patients (96%); for RMT they were 40 of 50 patients (80%) and 37 of 42 patients (88%). Study drugs were stopped due to side effects in three patients (6%) taking RAC and six patients (12%) taking RMT. Conclusions : Twice-daily RBC-based triple therapy with clarithromycin and amoxicillin produces Helicobacter pylori eradication rates over 90%, which is comparable to rates seen with proton pump inhibitor-based triple therapies. RBC also may be substituted for bismuth subsalicylate and an + H2-receptor antagonist in standard bismuth-based triple therapy.     

A synthetic host-guest system achieves avidin-biotin affinity by overcoming enthalpy-entropy compensation

The molecular host cucurbit[7]uril forms an extremely stable inclusion complex with the dicationic ferrocene derivative bis(trimethylammoniomethyl)ferrocene in aqueous solution. The equilibrium association constant for this host-guest pair is 3 × 10¹⁵ M⁻¹ (K_d = 3 × 10⁻¹⁶ M), equivalent to that exhibited by the avidin–biotin pair. Although purely synthetic systems with larger association constants have been reported, the present one is unique because it does not rely on polyvalency. Instead, it achieves its extreme affinity by overcoming the compensatory enthalpy–entropy relationship usually observed in supramolecular complexes. Its disproportionately low entropic cost is traced to extensive host desolvation and to the rigidity of both the host and the guest.     

Epidemiology and Determinants of Self-Injury Among High School Students in Iran: a Longitudinal Study

Non-suicidal self-injury (NSSI) among adolescents is a major health concern globally. The epidemiology and determinant of NSSI have not been studied extensively in Iran. Thus, this longitudinal study sought to investigate the prevalence, incidence and contributing factors of NSSI among adolescents in Iran. This study was conducted at high school students aged 14–18 years old in the metropolitan city of Tabriz, located in north western Iran. Data were collected from 6229 10th-grade students at two time-points, with 12 months interval in October and November 2017 and 2018. A self-administered questionnaire was used to collect information on demographic, NSSI and cigarette and hookah smoking from the study participants. The results showed that lifetime prevalence of NSSI among students was 6.2% (95% confidence interval [CI]: 5.7 to 6.9) at the first assessment. Scratching and hair pulling were the most and least common methods of self-injury, respectively. Over the one year, 206 students (3.6% CI 95%: 3.1–4.1) reported the onset of NSSI. Tobacco smoking and previous year average grade were related to the incidence of NSSI. Although gender was significantly associated with the prevalence of NSSI, the relationship between gender and incidence of NSSI was not significant. Although the prevalence of NSSI was low among adolescents, the incidence rate was considerable. Further studies are required to understand the risk factors of NSSI in Iran.

     

Multiple dopamine receptor subtypes in the medial prefrontal cortex of the rat regulate set-shifting.

Dopamine (DA) input to the prefrontal cortex (PFC), acting on D1 receptors, plays an essential role in mediating working memory functions. In comparison, less is known about the importance of distinct PFC DA receptor subtypes in mediating executive functions such as set-shifting. The present study assessed the effects of microinfusion of D2 and D4 receptor antagonists, and D1, D2, and D4 receptor agonists into the PFC on performance of a maze-based set-shifting task. In Experiment 1, rats were trained on a response discrimination task, and then on a visual-cue discrimination task requiring rats to suppress the use of the response strategy and approach the previously irrelevant cue to locate food. In Experiment 2, the order of training was reversed. Infusions of the D2 antagonist eticlopride, or the D4 agonist PD-168,077, impaired shifting from a response to a visual-cue discrimination strategy and vice versa, and caused a selective increase in perseverative errors. In contrast, infusions of the D4 antagonist L-745,870 improved set-shifting. Infusions of the D1 agonist SKF81297 or the D2 agonist quinpirole caused no reliable effect. These data, in combination with previous reports of impaired set-shifting following D1 receptor blockade, suggest that multiple receptors in the PFC are essential for set-shifting and that the mechanisms by which PFC DA mediates behavioral flexibility may be different from those underlying working memory. These findings may have important implications for developing novel treatments for cognitive deficits observed in disorders such as attentional deficit and hyperactivity disorder and schizophrenia.