Fighting COVID-19 / Combatendo a COVID-19

Abstract The current COVID-19 pandemic caused by the novel coronavirus (SARS-CoV2) poses a threat to global health owing to its high rate of spread and severe forms of respiratory infection. The lack of vaccines and antivirals prevents clinical strategies against the disease, creating an emerging need for the development of safe and effective treatments. Strategies for vaccine development include complete vaccines against viruses, subunits, and nucleic acids, but are still in their early stages. Studies carried out to date on possible SARS-CoV2 drug targets highlight glycoprotein S, Mpro (main protease or protease type 3C), and a member of the transmembrane serine protease II families (TMPRSS2). However, due to the pandemic state, priority is given to marketed drugs. These include chloroquine (CQ), hydroxychloroquine (HCQ), nitazoxanide, remdesivir, Lopinavir/ritonavir (LPV / r), in addition to treatment with convalescent plasma. But, therapeutic specific effects against SARS-CoV2 have not yet been verified. Most of the information obtained about treatment is based on preliminary and limited studies. We conclude that, at this time of emergency, the search for new therapies is more urgent due to the need to save lives. Thus, we point out as interesting targets for future more specific research: glycoprotein S, Mpro, and TMPRSS2.

Resumo A pandemia de COVID-19 causada pelo novo Coronavírus (SARS-CoV2) representa uma ameaça à saúde global devido à alta taxa de disseminação e formas graves de infecção respiratória. A falta de vacinas e antivirais específicos dificultam as estratégias clínicas de controle da doença, criando a necessidade urgente do desenvolvimento de tratamentos seguros e eficazes. Com relação as estratégias para o desenvolvimento de vacinas, incluem-se: aquelas com o vírus completo, subunidades e ácidos nucléicos, mas estas ainda estão em estágios iniciais. Já sobre os estudos realizados até o momento buscando novos alvos terapêuticos contra o SARS-CoV2, destacam a glicoproteína S; Mpro (principal protease ou protease tipo 3C) e um membro da família transmembrana serina protease II (TMPRSS2). No entanto, devido ao estado pandêmico, tem sido dada prioridade aos medicamentos comercializados. Estes incluem a cloroquina (CQ); hidroxicloroquina (HCQ); nitazoxanida; remdesivir; Lopinavir / ritonavir (LPV/r); além do tratamento com plasma de pacientes curados. Porém, ainda não há uma estratégia terapêutica contra o SARS-CoV2 totalmente eficaz, e a maioria das informações obtidas sobre o tratamento é baseada em estudos preliminares e limitados. Concluímos então que, neste momento de emergência, a busca por novas terapias é algo urgente devido à necessidade de salvar vidas. Assim finalizamos sugerindo como alvos interessantes para futuras pesquisas específicas: a glicoproteína S, Mpro e o TMPRSS2.

Fighting COVID-19.

The current COVID-19 pandemic caused by the novel coronavirus (SARS-CoV2) poses a threat to global health owing to its high rate of spread and severe forms of respiratory infection. The lack of vaccines and antivirals prevents clinical strategies against the disease, creating an emerging need for the development of safe and effective treatments. Strategies for vaccine development include complete vaccines against viruses, subunits, and nucleic acids, but are still in their early stages. Studies carried out to date on possible SARS-CoV2 drug targets highlight glycoprotein S, Mpro (main protease or protease type 3C), and a member of the transmembrane serine protease II families (TMPRSS2). However, due to the pandemic state, priority is given to marketed drugs. These include chloroquine (CQ), hydroxychloroquine (HCQ), nitazoxanide, remdesivir, Lopinavir/ritonavir (LPV / r), in addition to treatment with convalescent plasma. But, therapeutic specific effects against SARS-CoV2 have not yet been verified. Most of the information obtained about treatment is based on preliminary and limited studies. We conclude that, at this time of emergency, the search for new therapies is more urgent due to the need to save lives. Thus, we point out as interesting targets for future more specific research: glycoprotein S, Mpro, and TMPRSS2.

Interference of age and supplementation of direct-fed microbial and essential oil in the activity of digestive enzymes and expression of genes related to transport and digestion of carbohydrates and proteins in the small intestine of broilers.

The objectives of this study were to describe alterations that age and dietary inclusion of direct-fed microbial (DFM) Bacillus subtilis (BS) and a specific essential oil (EO) blend (carvacrol, cinnamaldehyde, cineol, and pepper extract) causes in the activity of digestive enzymes (maltase: MALT; aminopeptidase-N: APN; intestinal alkaline phosphate: IAP) and expression patterns of genes related to transport (oligopeptide transporter gene: SLC15A1; Na+-dependent glucose and galactose transporter gene: SLC5A1; Na+-independent glucose, galactose, and fructose transporter gene: SLC2A2; ATPase, Na+/K+ transporting gene: ATP1A1) and digestion (aminopeptidase-N gene: ANPEP; maltase-glucoamylase gene: MGAM; Sucrase-isomaltase gene: SI) of carbohydrates and proteins in the small intestine of broilers. Also, the objective was to analyze if growth performance of broilers is affected by supplementation (BS and EO blend). Day-old male broiler chicks (n = 1,320) were assigned to 5 treatments. Diets included a basal diet (BD) as a negative control (CON); experimental diets were BD + BS; BD + BS + EO; BD + EO; BD + antibiotic growth promoter (AGP) avilamycin was the positive control. Performance was evaluated between 1 to 42 d. Transcript abundance of transport-related genes and digestion-related genes were assayed by RT-qPCR and determined at d 7, 21, and 42. MALT-, APN-, and IAP-specific activities were determined at d 7, 21, and 42. Broilers fed BS had greater SLC15A1 mRNA abundance compared to CON, while EO and AGP were related to higher activities of IAP and APN. Analysis over time revealed higher abundance of MGAM, SLC2A2, SLC15A1, SLC5A1 and SI mRNA at d 42 when compared to d 7. Activity of IAP decreased after d 7 and activity of MALT increased with age. The current study suggests that age had effect over carbohydrate and protein transport and carbohydrate digestion. The supplementation of BS DFM hade evident effect over protein transport and that the use of EO in the diet enhanced the activities of carbohydrate and protein digestion, reflecting improvement in digestive and transport physiology of birds. Changes performed by BS DFM and EO did not favor performance.

Fighting COVID-19

Abstract The current COVID-19 pandemic caused by the novel coronavirus (SARS-CoV2) poses a threat to global health owing to its high rate of spread and severe forms of respiratory infection. The lack of vaccines and antivirals prevents clinical strategies against the disease, creating an emerging need for the development of safe and effective treatments. Strategies for vaccine development include complete vaccines against viruses, subunits, and nucleic acids, but are still in their early stages. Studies carried out to date on possible SARS-CoV2 drug targets highlight glycoprotein S, Mpro (main protease or protease type 3C), and a member of the transmembrane serine protease II families (TMPRSS2). However, due to the pandemic state, priority is given to marketed drugs. These include chloroquine (CQ), hydroxychloroquine (HCQ), nitazoxanide, remdesivir, Lopinavir/ritonavir (LPV / r), in addition to treatment with convalescent plasma. But, therapeutic specific effects against SARS-CoV2 have not yet been verified. Most of the information obtained about treatment is based on preliminary and limited studies. We conclude that, at this time of emergency, the search for new therapies is more urgent due to the need to save lives. Thus, we point out as interesting targets for future more specific research: glycoprotein S, Mpro, and TMPRSS2.

Resumo A pandemia de COVID-19 causada pelo novo Coronavírus (SARS-CoV2) representa uma ameaça à saúde global devido à alta taxa de disseminação e formas graves de infecção respiratória. A falta de vacinas e antivirais específicos dificultam as estratégias clínicas de controle da doença, criando a necessidade urgente do desenvolvimento de tratamentos seguros e eficazes. Com relação as estratégias para o desenvolvimento de vacinas, incluem-se: aquelas com o vírus completo, subunidades e ácidos nucléicos, mas estas ainda estão em estágios iniciais. Já sobre os estudos realizados até o momento buscando novos alvos terapêuticos contra o SARS-CoV2, destacam a glicoproteína S; Mpro (principal protease ou protease tipo 3C) e um membro da família transmembrana serina protease II (TMPRSS2). No entanto, devido ao estado pandêmico, tem sido dada prioridade aos medicamentos comercializados. Estes incluem a cloroquina (CQ); hidroxicloroquina (HCQ); nitazoxanida; remdesivir; Lopinavir / ritonavir (LPV/r); além do tratamento com plasma de pacientes curados. Porém, ainda não há uma estratégia terapêutica contra o SARS-CoV2 totalmente eficaz, e a maioria das informações obtidas sobre o tratamento é baseada em estudos preliminares e limitados. Concluímos então que, neste momento de emergência, a busca por novas terapias é algo urgente devido à necessidade de salvar vidas. Assim finalizamos sugerindo como alvos interessantes para futuras pesquisas específicas: a glicoproteína S, Mpro e o TMPRSS2.

Performance and carbon turnover in fast- and slow-growing broilers submitted to cyclic heat stress and fed on high-protein diets.

Two experiments were conducted to test the hypothesis that when using similar protein/amino acid diets and environment temperature conditions, the performance and carbon turnover in muscle and liver tissues, as measured by the incorporation of stable isotopes ((13)C/(12)C), must be different between fast-growing Cobb 500® and slow-growing Label Rouge broilers. For both experiments (Cobb and Label Rouge), 21-d-old birds were distributed in a completely randomised, 3 × 3 factorial design; three environmental temperatures (cyclic heat stress ad libitum, 22°C ad libitum, and 22°C restricted) and three crude protein concentrations (189.1, 210 and 220 g/kg CP) were used. The Cobb 500® had better performance with higher concentrations of crude protein. Cyclic heat stress (a temperature factor), negatively affected this genetic strain's performance. For the Label Rouge birds, the crude protein concentrations in the diet presented inconsistent results and cyclic heat stress did not affect the performance. The carbon turnover rate was affected in the Cobb 500® strain, with a high protein content reducing carbon turnover in the evaluated tissues (liver and muscles). Feed intake had a greater impact on carbon turnover rates than cyclic heat stress. The Label Rouge birds were not affected by the evaluated factors, suggesting that genetic improvement has a leading role on tissue carbon turnover. There is a genetic influence on carbon turnover in the liver and muscle tissues of broiler chickens. In addition, genetically fast-growing broilers are more susceptible to variations in diet composition and environmental temperature than less rapidly growing animals.

Effects of corn replacement by sorghum in broiler diets on performance and intestinal mucosa integrity.

The effect of replacing corn with low-tannin sorghum on broiler performance, carcass yield, integrity of mucosa of small intestine segments, and activity of membrane enzymes of the jejunum is investigated. A total of 594 male Cobb-500 broiler chicks were randomly assigned to 3 dietary treatments: 100% corn (control), 50% corn replacement with low-tannin sorghum (low sorghum), and 100% corn replacement with low-tannin sorghum (high sorghum). Body weight gain, feed consumption, feed conversion, and carcass yield were determined at 7, 21, and 42 d, and segments of the small intestine were collected. Feed conversion and weight gain were impaired at d 42 in broilers fed the high-sorghum diet, but no differences were observed for carcass yield among the treatments (P > 0.05). Crypt cell mitotic index of the jejunum and ileum at d 21 and 42 was lower in broilers fed the control diet than in those fed low- and high-sorghum diets (P < 0.05). Aminopeptidase activity was higher in broilers fed the control diet than in those fed low- and high-sorghum diets irrespective of age (P < 0.05). Conversely, intestinal alkaline phosphatase activity in the small intestine did not differ among the dietary treatments (P > 0.05). Our results indicate that 50% corn replacement with low-tannin sorghum is suitable for broiler diets, whereas 100% corn replacement with low-tannin sorghum had negative effects on the intestinal mucosa and performance of broilers at 42 d.

Polarized expression of the GFP-tagged rat V(1a) vasopressin receptor.

We investigated the targeting of the V(1a) receptor fused with the green fluorescence protein (V(1a)R-GFP) in polarized MDCK cells. Cells expressing V(1a)R-GFP displayed binding to vasopressin (AVP) and AVP-induced calcium responses, similar to cells expressing the wild-type V1a receptor. Interestingly, as with the wild-type V(1a)R, V(1a)R-GFP is preferentially distributed in the basolateral side of MDCK cells as monitored by confocal microscopy. Furthermore, AVP induced internalization of GFP-tagged receptors. Therefore, the GFP-tagged V(1a) receptor retains all the sorting signals of the wild-type receptor and offers an excellent system to elucidate the mechanisms of cell trafficking of V(1a) receptors.

[Assessment of ivermectin therapeutic efficacy on fourth-stage larvae of Lagochilascaris minor in experimentally infected cats]. / Avaliação da eficácia terapêutica da ivermectina sobre larvas de quarto estádio de Lagochilascaris minor em gatos infectados experimentalmente.

In order to verify the action of ivermectin against fourth-stage larvae of Lagochilascaris minor, thirty cats were divided into three groups (I, II and III). Each animal was inoculated orally with 50 third-stage larvae. The cats from groups I and II were treated with Ivermectin (200/microg/kg/single dose/sc via) on fifth day after inoculation (DAI). Treatment evaluation was performed between 30 and 40 DAI (group I) and between 180 to 190 DAI (group II) using parasite macroscopic and microscopic research at autopsy. The 10 cats from group III were untreated (control group). The authors observed 100% drug efficacy, at all observation periods, by total interruption of parasite's biological cycle in each of the treated animals. All the control group developed Lagochilascaris minor infection.

Avaliação da eficácia terapêutica da ivermectina sobre larvas de quarto estádio de Lagochilascaris minor em gatos infectados experimentalmente / Assessment of ivermectin therapeutic efficacy on fourth-stage larvae of Lagochilascaris minor in experimentally infected cats

Avaliou-se a ação da ivermectina sobre larvas de quarto estádio em gatos infectados experimentalmente com Lagochilascaris minor. Foram utilizados 30 gatos (divididos, igualmente, em três grupos I, II e III), sendo que cada animal foi inoculado, por via oral, com 50 larvas de terceiro estádio do parasito. Cada animal, dos grupos I e II, foi tratado com ivermectina na dosagen de 200mg/kg, no quinto dia após o inóculo (DAI). Os animais do grupo I foram examinados, clinicamente, entre 30 e 40 dias e os do grupo II entre 180 e 190 dias sendo, em seguida, submetidos à necropsia. Os dez animais do grupo III, não foram tratados com a droga constituindo o grupo controle. Independentemente do período de observação, observou-se 100% de eficácia da droga, visto que houve total interrupção do ciclo biológico do parasito em todos animais tratados. Todos animais do grupo controle desenvolveram a infecção por Lagochilascaris minor.

In order to verify the action of ivermectin against fourth-stage larvae of Lagochilascaris minor, thirty cats were divided into three groups (I, II and III). Each animal was inoculated orally with 50 third-stage larvae. The cats from groups I and II were treated with Ivermectin (200/microg/kg/single dose/sc via) on fifth day after inoculation (DAI). Treatment evaluation was performed between 30 and 40 DAI (group I) and between 180 to 190 DAI (group II) using parasite macroscopic and microscopic research at autopsy. The 10 cats from group III were untreated (control group). The authors observed 100% drug efficacy, at all observation periods, by total interruption of parasite's biological cycle in each of the treated animals. All the control group developed Lagochilascaris minor infection.

Parasitological and immunological diagnoses of strongyloidiasis in immunocompromised and non-immunocompromised children at Uberlândia, State of Minas Gerais, Brazil.

Parasitological and immunological diagnoses were part of a study conducted among 151 children, 83 immunocompromised (IC) and 68 non-immunocompromised (non-IC) aged from zero to 12, seen at the University Hospital, Universidade Federal de Uberlândia, State of Minas Gerais, Brazil, from February, 1996, to June, 1998. Three fecal samples from each child were analyzed for the parasitological diagnosis by Baermann-Moraes and Lutz methods. The immunological diagnosis to detect IgG and IgM antibodies was carried out by the indirect immunofluorescence antibody test (IFAT) with cryo-microtome sections of Strongyloides stercoralis and Strongyloides ratti larvae as antigens and by the ELISA test with an alkaline extract of S. ratti as the antigens. Of the 151 children 5 (3.31%) were infected with larvae of S. stercoralis (2 cases IC, 2.41%, and 3 cases non-IC, 4.41%). The IFAT-IgG detected 7 (8.43%) serum samples positive among IC, and 2 (2.94%) cases among non-IC. The ELISA-IgG test detected 10 (12.05%) serum samples positive among IC, and 1 (1.47%) case among non-IC. The IFAT-IgM detected 6 (7.22%) positive cases among IC, and 3 (4.41%) cases among non-IC. ELISA-IgM test detected 10 (12.05%) positive cases among IC, and 3 (4.41%) cases among non-IC. It was concluded that the immunological tests can help in the diagnosis of strongyloidiasis in immunocompromised children.

Wild rodents as experimental intermediate hosts of Lagochilascaris minor Leiper, 1909.

A total of 25 specimens of Cavia porcellus (guinea pig), 5 Dasyprocta agouti (agouti), and 22 Calomys callosus (vesper mice) were inoculated with infective eggs of Lagochilascaris minor. The inoculum was prepared with embryonated eggs and orally administered to each individual animal through an esophagus probe. In parallel, 100 specimens of Felis catus domesticus were individually fed with 55-70 nodules containing 3rd-stage larvae encysted in tissues of infected rodents. Animals were examined and necropsied at different time intervals. The migration and encystment of L3 larva was observed in viscera, skeletal muscle, adipose and subcutaneous tissues from all rodents. Adult worms localized at abscesses in the cervical region, rhino, and oropharynx were recovered from domestic cats inoculated with infected rodent tissues. Through this study we can conclude that: (1) wild rodents act as intermediate hosts, characterizing this ascarid heteroxenic cycle; (2) in natural conditions rodents could possibly act as either intermediate hosts or paratenic hosts of Lagochilascaris minor; (3) despite the occurrence of an auto-infecting cycle, in prime-infection of felines (definite hosts) the cycle is only completed when intermediate hosts are provided; and (4) in the wild, rodents could serve as a source of infection for humans as they are frequently used as food in regions with the highest incidence of human lagochilascariasis.

Assessment of ivermectin therapeutic efficacy on third-stage larvae of Lagochilascaris minor in mice experimentally infected.

In this study we evaluated the potential action of ivermectin on third-stage larvae, both at migratory and encysted phases, in mouse tissues after experimental infection with Lagochilascaris minor. Study groups I and II consisted of 120 mice that were orally administered 1,000 parasite eggs. In order to assess ivermectin action upon migratory larvae, group I (60 mice) was equally split in three subgroups, namely I-A, I-B, and I-C. On the 7th day after inoculation (DAI), each animal from the subgroup I-A was treated with 200 micrograms/Kg ivermectin while subgroup I-B was given 1,000 micrograms/Kg, both groups received a single subcutaneous dose. To assess the drug action on encysted larvae, group II was equally split in three subgroups, namely II-A, II-B, II-C. On the 45th DAI each animal was treated with ivermectin at 200 micrograms/Kg (subgroup II-A) and 1,000 micrograms/Kg (group II-B) with a single subcutaneous dose. Untreated animals of subgroups I-C and II-C were used as controls. On the 60th DAI all animals were submitted to larva search. At a dose of 1,000 micrograms/Kg the drug had 99.5% effectiveness on third-stage migratory larvae (subgroup I-B). Ivermectin efficacy was lower than 5% on third-stage encysted larvae for both doses as well as for migratory larvae treated with 200 micrograms/Kg.

Cryo-microtome sections of coproculture larvae of Strongyloides stercoralis and Strongyloides ratti as antigen sources for the immunodiagnosis of human strongyloidiasis.

Cryo-microtome sections of larvae of Strongyloides stercoralis and S. ratti respectively obtained from human and rat feces cultures, were used as antigens. Fluoresceinate conjugates against human IgG were employed at the ideal titer of 10 for S. stercoralis and 100 for S. ratti. The sensitivity of the indirect immunofluorescence reaction (IIF) was 94.4% and 92.5% and the specificity 94.2% and 97.1% for the two specific larval antigens, respectively. Sera from 123 persons (54 from carriers of S. stercoralis infections and 69 from controls) were submitted to the reaction. The titers of different sera varied from 20 to 2560. There was a significant linear correlation (r = 0.85 p < or = 0.001) between the antibodies from the two species of larval antigens. We conclude that both antigens may be used in the IIF reaction for the diagnosis of human strongyloidiasis. Due to the feasibility of safe and low-cost mass production of S. ratti larvae in the laboratory with a considerable economy of conjugate, their utilization in the serum diagnosis of human strongyloidiasis is recommended.

[Recurrent confusional states and periodic lateralized epileptiform discharges: a new type of non-convulsive status epilepticus?]. / Síndrome confusional recurrente y complejos periódicos: un nuevo tipo de status no convulsivo?

Periodic lateralized epileptiform discharges (PLEDs) in an EEG usually indicate the presence of an underlying structural lesion (of vascular origin in most cases). PLEDs are also sometimes observed in certain types of infections (mainly viral), in which they may even constitute a characteristic finding useful for diagnostic purposes. In recent years cases have been reported in which PLEDs are linked to recurring confusional states that do not fit in with established classifications and that may be epileptic in nature. We discuss the cases of 2 patients who were repeatedly admitted to our hospital in confusional states, in whom PLEDs were observed in EEG readings. Clinical evolution in both cases paralleled EEG alterations. We were able to perform both critical and intercritical single proton emission tomography on 1 patient, finding, respectively, hyper- and hypoabsorption foci. Symptoms resolved with antiepileptic treatment.

[Nuclear syndrome of the oculomotor nerve caused by a mesencephalic infarction confirmed by MRI]. / Síndrome "nuclear" del motor ocular común por infarto mesencefálico confirmado con RM.

The nuclear syndrome of the third nerve was first described in 1981. It has the very characteristic disturbance of an ophthalmoplegia with complete ipsilateral third nerve palsy associated with paresis of elevation in contralateral eye. This particularly presentation is due to the innervation of the superior rectus which comes mainly from the contralateral oculomotor nucleus. As associated signs were described contralateral cerebellar and or pyramidal syndromes, uni or bilateral parasympathetic disfunction and sometimes gaze disorders. The etiology es usually a vascular damage (ischemic most frequently) located in mesencephalon. We report on a case of a 60 years old man who developed acute nuclear ophthalmoplegia of the third right nerve accompanied with cerebellar and pyramidal syndrome and focal asterixis in left extremities. MRI showed an ischemic lesion in right paramedial mesencephalic territory with extension to the ipsilateral thalamic region. Pyramidal and cerebellar syndromes and asterixis disappeared in a few weeks, while ophthalmoplegia remained unchanged. Semiologic characteristics and anatomic basis of the nuclear oculomotor syndrome which allow to make the differential diagnosis between this syndrome and intra-axial fascicular disturbances of the third nerve (Weber, Claude and Benedikt syndromes) are discuss.