Contribution of Transcriptome to Elucidate the Biology of Plasmodium spp

In the present review, we discuss some of the new technologies that have been applied to elucidate how Plasmodium spp escape from the immune system and subvert the host physiology to orchestrate the regulation of its biological pathways. Our manuscript describes how techniques such as microarray approaches, RNA-Seq and single-cell RNA sequencing have contributed to the discovery of transcripts and changed the concept of gene expression regulation in closely related malaria parasite species. Moreover, the text highlights the contributions of high-throughput RNA sequencing for the current knowledge of malaria parasite biology, physiology, vaccine target and the revelation of new players in parasite signaling.

Quinacrine, an Antimalarial Drug with Strong Activity Inhibiting SARS-CoV-2 Viral Replication In Vitro

Quinacrine (Qx), a molecule used as an antimalarial, has shown anticancer, antiprion, and antiviral activity. The most relevant antiviral activities of Qx are related to its ability to raise pH in acidic organelles, diminishing viral enzymatic activity for viral cell entry, and its ability to bind to viral DNA and RNA. Moreover, Qx has been used as an immunomodulator in cutaneous lupus erythematosus and various rheumatological diseases, by inhibiting phospholipase A2 modulating the Th1/Th2 response. The aim of this study was to evaluate the potential antiviral effect of Qx against denominated severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection in Vero E6 cells. The cytotoxicity of Qx in Vero E6 cells was determined by the MTT assay. Afterwards, Vero E6 cells were infected with SARS-CoV-2 at different multiplicities of infections (MOIs) of 0.1 and 0.01 in the presence of Qx (0-30 µM) to determinate the half maximal effective concentration (EC50). After 48 h, the effect of Qx against SARS-CoV-2 was assessed by viral cytotoxicity and viral copy numbers, the last were determined by digital real-time RT-PCR (ddRT-PCR). Additionally, electron and confocal microscopy of Vero E6 cells infected and treated with Qx was studied. Our data show that Qx reduces SARS-CoV-2 virus replication and virus cytotoxicity, apparently by inhibition of viral ensemble, as observed by ultrastructural images, suggesting that Qx could be a potential drug for further clinical studies against coronavirus disease 2019 (COVID-19) infection.

Prevalence of Gastroesophageal Reflux in Cats During Anesthesia and Effect of Omeprazole on Gastric pH

Background

Gastroesophageal reflux (GER) is poorly characterized in anesthetized cats, but can cause aspiration pneumonia, esophagitis, and esophageal stricture formation.

Objective

To determine whether pre‐anesthetic orally administered omeprazole increases gastric and esophageal pH and increases serum gastrin concentrations in anesthetized cats, and to determine the prevalence of GER using combined multichannel impedance and pH monitoring.

Animals

Twenty‐seven healthy cats undergoing elective dental procedures.

Methods

Prospective, double‐masked, placebo‐controlled, randomized clinical trial. Cats were randomized to receive 2 PO doses of omeprazole (1.45–2.20 mg/kg) or an empty gelatin capsule placebo 18–24 hours and 4 hours before anesthetic induction. Blood for measurement of serum gastrin concentration was collected during anesthetic induction. An esophageal pH/impedance catheter was utilized to continuously measure esophageal pH and detect GER throughout anesthesia.

Results

Mean gastric pH in the cats that received omeprazole was 7.2 ± 0.4 (range, 6.6–7.8) and was significantly higher than the pH in cats that received the placebo 2.8 ± 1.0 (range, 1.3–4.1; P < .001). Omeprazole administration was not associated with a significant increase in serum gastrin concentration (P = .616). Nine of 27 cats (33.3%) had ≥1 episode of GER during anesthesia.

Conclusions and Clinical Relevance

Pre‐anesthetic administration of 2 PO doses of omeprazole at a dosage of 1.45–2.20 mg/kg in cats was associated with a significant increase in gastric and esophageal pH within 24 hours, but was not associated with a significant increase in serum gastrin concentration. Prevalence of reflux events in cats during anesthesia was similar to that of dogs during anesthesia.

Characteristics of a four element gyromagnetic nonlinear transmission line array high power microwave source

In this paper, a solid-state four element array gyromagnetic nonlinear transmission line high power microwave system is presented as well as a detailed description of its subsystems and general output capabilities. This frequency agile S-band source is easily adjusted from 2-4 GHz by way of a DC driven biasing magnetic field and is capable of generating electric fields of 7.8 kV/m at 10 m correlating to 4.2 MW of RF power with pulse repetition frequencies up to 1 kHz. Beam steering of the array at angles of ±16.7° is also demonstrated, and the associated general radiation pattern is detailed.

Material selection of a ferrimagnetic loaded coaxial delay line for phasing gyromagnetic nonlinear transmission lines

Implementing nonlinear transmission line (NLTL) technology in the design of a high power microwave source has the benefits of producing a comparatively small and lightweight solid-state system where the emission frequency is easily tuned. Usually, smaller in physical size, single NLTLs may produce significantly less power than its vacuum based counterparts. However, combining individual NLTL outputs electrically or in free-space is an attractive solution to achieve greater output power. This paper discusses a method for aligning a four element NLTL antenna array with coaxial geometry using easily adjustable temporal delay lines. These delay lines, sometimes referred to as pulse shock lines or pulse sharpening lines, are placed serially in front of the main NLTL line. The propagation velocity in each delay line is set by the voltage amplitude of an incident pulse as well as the magnetic field bias. Each is adjustable although for the system described in this paper, the voltage is held constant while the bias is changed through applying an external DC magnetic field of varying magnitude. Three different ferrimagnetic materials are placed in the temporal delay line to evaluate which yields the greatest range of electrical delay with the least amount of variability from consecutive shots.

High-resolution structure of a potent, cyclic proteinase inhibitor from sunflower seeds

Proteinaceous serine proteinase inhibitors are widespread throughout the plant kingdom where they play an important role in protection against pests and pathogens. Here, we describe the isolation and characterisation of a novel 14 amino acid residue cyclic peptide from sunflower seeds, which is a potent inhibitor of trypsin (Ki=100 pM). The crystal structure of this peptide in complex with bovine beta-trypsin shows both sequence and conformational similarity with the trypsin-reactive loop of the Bowman-Birk family of serine proteinase inhibitors. This inhibitor, however, is unique in being monofunctional, cyclic and far shorter (14 amino acid residues) than inhibitors belonging to this family (typically 60-70 amino acid residues). The high potency of this peptide is likely to arise from the considerable structural rigidity achieved through its cyclic nature which is further stabilised by a single internal disulphide bond. This study helps delineate the minimal unit required for effective peptide inhibitors of serine proteinases, and will assist in the further design of inhibitors to this widespread class of enzymes.

[Proved self-poisoning. A 10-year case load from an intensive care unit]

During the period 1.1.1979-31.12.1988, a total of 2.023 admissions (involving 1.511 patients) occurred on account of deliberate self-poisoning in the Intensive Care Unit of the Anaesthetic Department of Odense Hospital. No significant alterations were observed in the female/male ratio or in the average age, during this period. Duration of hospitalization in the Intensive Care Unit showed a decrease. The frequencies of cases of poisoning with barbiturates showed a decrease while poisonings with acetaminophen, alcohol and chemical-technical agents showed increasing frequencies. Poisoning with benzodiazepines, neuroleptics, polycyclic antidepressive drugs, dextropropoxyphen or acetylsalicylic acid occurred with unaltered frequency. Treatment consisted mainly of endotracheal intubation, artificial ventilation, circulatory therapy, forced alkaline diuresis, haemodialysis and antibiotic therapy. The frequency of forced alkaline diuresis decreased during the period while circulatory therapy, haemodialysis, antibiotic therapy and treatment with antidotes were employed increasingly frequently. The acute lethality was 1.6%. It is concluded that treatment was mainly symptomatic and concentrated on ensuring respiratory and circulatory functions and that the acute lethality is unchanged and will probably not be lowered further. The "Scandinavian method" is thus still the cornerstone in the treatment of poisoning and is responsible for the continued low acute lethality.

Subarachnoid versus epidural bupivacaine 0.5% for caesarean section

In order to compare subarachnoid (spinal) and epidural block for caesarean section, 40 women were randomly allocated to spinal or epidural analgesia with bupivacaine. The median dose of bupivacaine was 13 mg in the spinal group versus 155 mg in the epidural group. The mean time from induction to delivery was 32 min shorter in the spinal group (P less than 0.001). In the spinal group one woman was excluded because of spontaneous labour. Three patients in the spinal and one in the epidural group failed to develop adequate analgesia to initiate surgery. For the remaining patients both techniques provided good analgesia during operation. Postoperatively, epidural block provided better pain relief. The patients in the epidural group had a lower pain score during the first 4 h after the operation (P less than 0.01). In spite of similar haemodynamic changes in the two groups, the mean base deficit in umbilical cord blood at delivery was higher in the spinal group (P less than 0.05).