Identification of Hypericin as a Candidate Repurposed Therapeutic Agent for COVID-19 and Its Potential Anti-SARS-CoV-2 Activity.

The COVID-19 pandemic has had an unprecedented impact on the global economy and public health. Its etiologic agent, the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is highly transmissible, pathogenic and has a rapid global spread. Currently, the increase in the number of new confirmed cases has been slowed down due to the increase of vaccination in some regions of the world.

Racial and Ethnic Differences in Communication and Care for Children With Advanced Cancer.

Context: Racial and ethnic disparities in end-of-life care are well documented among adults with advanced cancer.

Objectives: To examine the extent to which communication and care differ by race and ethnicity among children with advanced cancer.

Methods: We conducted a prospective cohort study at nine pediatric cancer centers enrolling 95 parents (42% racial/ethnic minorities) of children with poor prognosis cancer (relapsed/refractory high-risk neuroblastoma).

The complementarity-determining region sequences in IgY antivenom hypervariable regions.

The data presented in this article are related to the research article entitled "Development of IgY antibodies against anti-snake toxins endowed with highly lethal neutralizing activity" (da Rocha et al., 2017) [1]. Complementarity-determining region (CDR) sequences are variable antibody (Ab) sequences that respond with specificity, duration and strength to identify and bind to antigen (Ag) epitopes.

Development of IgY antibodies against anti-snake toxins endowed with highly lethal neutralizing activity.

Snakebite envenoming is a major neglected disease related to poverty in developing countries. Treatment involves the administration of a specific antivenom serum and auxiliary therapies, if necessary. The improvement of antibodies is of great importance for the technological advancement of antivenom therapy and to reduce the morbidity and mortality associated with this medical burden.

Partial characterization of an atypical family I inorganic pyrophosphatase from cattle tick Rhipicephalus (Boophilus) microplus.

The present paper presents the partial characterization of a family I inorganic pyrophosphatase from the hard tick Rhipicephalus (Boophilus) microplus (BmPPase). The BmPPase gene was cloned from the tick embryo and sequenced. The deduced amino acid sequence shared high similarity with other eukaryotic PPases, on the other hand, BmPPase presented some cysteine residues non-conserved in other groups.

In silico structural characteristics and α-amylase inhibitory properties of Ric c 1 and Ric c 3, allergenic 2S albumins from Ricinus communis seeds.

The major Ricinus communis allergens are the 2S albumins, Ric c 1 and Ric c 3. These proteins contain a trypsin/α-amylase inhibitor family domain, suggesting that they have a role in insect resistance. In this study, we verified that Ric c 1 and Ric c 3 inhibited the α-amylase activity of Callosobruchus maculatus, Zabrotes subfasciatus, and Tenebrio molitor (TMA) larvae as well as mammalian α-amylase.

Structural and biological characterization of Nattectin, a new C-type lectin from the venomous fish Thalassophryne nattereri.

Lectins are glycan-binding receptors that recognize glycan epitopes on foreign pathogens and in the host systems. They can be involved in functions that include innate immunity, development, immune regulation and homeostasis. Several lectins have been purified and characterized from fish species.

The action of fish peptide Orpotrin analogs on microcirculation.

In order to investigate the relationship between the primary structure of Orpotrin, a vasoactive peptide previously isolated from the freshwater stingray Potamotrygon gr. orbignyi, and its microcirculatory effects, three Orpotrin analogs were synthesized. The analogs have a truncated N-terminal with a His residue deletion and two substituted amino acid residues, where one Nle is substituted for one internal Lys residue and the third analog has a substitution of a Pro for an Ala (Orp-desH(1) , Orp-Nle and Orp-Pro/Ala, respectively).

Characterization of a new bioactive peptide from Potamotrygon gr. orbignyi freshwater stingray venom.

Brazilian freshwater stingrays, Potamotrygon gr. orbigyni, are relatively common in the middle-western regions of Brazil, where they are considered an important public health threat. In order to identify some of their naturally occurring toxin peptides available in very low amounts, we combine analytical protocols such as reversed-phase high-performance liquid chromatography (RP-HPLC), followed by a biological microcirculatory screening and mass spectrometry analysis.

Structural descriptor database: a new tool for sequence-based functional site prediction.

Background: The Structural Descriptor Database (SDDB) is a web-based tool that predicts the function of proteins and functional site positions based on the structural properties of related protein families. Structural alignments and functional residues of a known protein set (defined as the training set) are used to build special Hidden Markov Models (HMM) called HMM descriptors. SDDB uses previously calculated and stored HMM descriptors for predicting active sites, binding residues, and protein function.

Glutathione S-transferase and aluminum toxicity in maize.

Aluminum (Al) toxicity induces changes in the expression of several genes, some of which are involved in plant responses to oxidative stress. Using mRNA differential display, we identified a maize Al-inducible cDNA encoding a glutathione S-transferase (GST). The gene was named GST27.

Molecular cloning, functional expression, and molecular modeling of bothrostatin, a new highly active disintegrin from Bothrops jararaca venom.

Disintegrins are among the most potent antagonists of several integrins. A cDNA encoding a novel disintegrin, bothrostatin, was cloned from a Bothrops jararaca cDNA library. The precursor of bothrostatin contains a pro, a metalloproteinase, and an RGD-disintegrin domain.

Using bradykinin-potentiating peptide structures to develop new antihypertensive drugs.

Angiotensin I-converting enzyme (ACE) is a dipeptidyl-carboxypeptidase expressed in endothelial, epithelial and neuroepithelial cells. It is composed of two domains, known as N- and C-domains, and it is primarily involved in blood pressure regulation. Although the physiological functions of ACE are not limited to its cardiovascular role, it has been an attractive target for drug design due to its critical role in cardiovascular and renal disease.

Structural basis of the lisinopril-binding specificity in N- and C-domains of human somatic ACE.

Angiotensin I-converting enzyme (ACE) is a dipeptidyl carboxypeptidase which converts angiotensin I into the vasopressor peptide angiotensin II and also inactivates the hypotensive peptide bradykinin, playing an important role in blood pressure regulation. The present work describes the molecular modeling of the N-terminal human somatic ACE in complex with the inhibitor lisinopril, identifying the residues involved in the inhibitor-binding pocket. The obtained results identify differences in the lisinopril lysine moiety-binding residues for N- and C-terminals of sACE domains and an important carboxy-terminal proline hydrophobic accommodations mediated by the aromatic ring of Tyr532 and Tyr1128 residues, respectively.