Hepatic damage caused by flaviviruses: A systematic review

Flaviviruses infect arthropods and mammals and their pathologies are a considerable global health problem, affecting about 400 million people per year. The symptoms of these flaviviruses range from mild manifestations such as nausea, vomiting, and headache to more serious cases such as hemorrhage, meningitis, microcephaly, kidney, and liver failure. This review aims to compile the morphological changes that occur due to infections caused by dengue, yellow fever, and Zika viruses, as well as to describe possible mechanisms of action of such flaviviruses in the liver. PRISMA guidelines were used to search for studies associating flavivirus with liver disorders. Two independent reviewers selected the studies on PubMed/Medline, Web of Science, and Scopus search platforms. The SYRCLE software was used for the evaluation of the study's quality. Eighteen experimental articles were included. The experimental animals often used in experiments were monkeys (5 %), hamsters (10 %), chicken embryos (10 %), and mice (75 %). It is evident that there is a strong hepatic interaction with flaviviruses, and the main hepatic alterations found were steatosis, apoptosis, necrosis, hemorrhage, elevation of ALT and AST levels, and total bilirubin. Flavivirus infection, in general, trigger an upregulation of pro-inflammatory cytokines, leading to structural changes in mitochondria that activate cascades of cellular death and promote insulin resistance. The majority of the studies primarily focus on dengue and yellow fever viruses, while the findings related to Zika virus exposure are still relatively limited and require further investigation.

The Size But not the Symmetry of the Wings of Eulaema nigrita Lepeletier (Apidae: Euglossini) is Affected by Human-Disturbed Landscapes in the Brazilian Cerrado Savanna

Among other human-related activities, habitat loss and fragmentation are currently ranked as the most important environmental features affecting the persistence of animal and plant populations in landscapes, as well as the maintenance of ecological processes and services. Since these processes are also capable of affecting the ontogenetic development of species inhabiting those landscapes, here we measured the wing veins of male Eulaema nigrita Lepeletier (Apidae: Euglossini) bees in order to evaluate whether the bees sampled in agriculture (AG) areas suffer higher fluctuating asymmetry (FA) than those sampled in Cerrado (CE) areas in the Brazilian state of Goiás. We believe that individuals sampled in CE areas would be less asymmetric than those sampled in AG areas, given a potential higher exposure of these specimens to environmental stresses (mostly pesticides). However, we did not observe a significant trend in the FA measures we obtained, although three wing measures were bigger for bees from CE areas. The lack of significant effects of FA may be related to inherent bionomic features of E. nigrita. For instance, given their high individual dispersal abilities, the individuals we analyzed may have developed in different areas than those where they were sampled. Their generalist feeding behavior may also have given them a higher resistance to environmental perturbations, buffering the normal development of immatures even in areas with local high environmental stress. Nonetheless, higher death rates of individuals from anthropic areas may also have killed the developing immatures of E. nigrita before they reached adulthood consequently equalizing our sampled estimates.

An efficient protocol for tissue sampling and DNA isolation from the stem bark of Leguminosae trees

Traditionally, molecular studies of plant species have used leaves as the source of DNA. However, sampling leaves from tall tree species can be quite difficult and expensive. We developed a sequence of procedures for using stem bark as a source of DNA from Leguminosae trees of the Atlantic Forest and the Cerrado. Leguminosae is an important species-rich family in these two highly diverse and endangered biomes. A modified CTAB protocol for DNA isolation is described, and details of the procedures for sampling and storage of the bark are given. The procedures were initially developed for three species, and then their applicability for 15 other species was evaluated. DNA of satisfactory quality was obtained from the bark of all species. The amounts of DNA obtained from leaves were slightly higher than from bark samples, while its purity was the same. Storing the bark frozen or by drying in silica gel yielded similar results. Polymerase chain reaction amplification worked for both plastid and nuclear genomes. This alternative for isolating DNA from bark samples of trees facilitates field work with these tree species.

Acid secretory response in the late follow-up of proximal gastric vagotomy for duodenal ulcer without Helicobacter pylori eradication

BACKGROUND/AIMS

The profile of acid secretory responses was studied in 20 patients who had had proximal gastric vagotomy (PGV) surgery performed 11-22 years previously in order to treat duodenal ulcers (DU). The presence of Helicobacter pylori was detected in all of the patients.

METHODOLOGY

The recurrence of DU was diagnosed in 10 patients and the other 10 remained without recurrence during the follow-up period. The control groups included 10 DU patients with refractory responses to H2 receptor antagonists and 10 "normal" subjects. Both control groups had untreated Helicobacter pylori infection. Measures of 1) basal acid output, 2) acid output for 30 min under continuous i.v. infusion of 0.2 ug/kg/h of pentagastrin acid, and 3) the response for 30 and 60 min after starting a sham feeding, modified by the "chew and spit" technique under simultaneous i.v. infusion of 0.2 ug/kg/h of pentagastrin were performed. Serum gastrin was measured during fasting and at sham feeding. The densities of the gastrin cells of antrum and duodenum were estimated by morphometric counting.

RESULTS

Both basal output and acid response to sham feeding plus pentagastrin infusion were higher in the DU controls and DU recurrence patients. The response to pentagastrin infusion did not show any discriminant value. Fasting serum gastrin values increased after PGV, either with or without DU recurrence. Gastrin cell hyperplasia was not demonstrated in any of these groups.

CONCLUSIONS

The secretory profile of patients with both late DU recurrence after PGV and Helicobacter pylori infection lies between DU patients refractory to the H2 receptor antagonist approach and those free of DU recurrence after PGV--both of them with current Helicobacter pylori infection. The characteristic pattern of late DU recurrence after PGV and untreated Helicobacter infection is that of increased basal acid output and higher acid secretion responsiveness to sham feeding plus pentagastrin in the presence of higher serum levels of gastrin.

[Conservative treatment of pseudomyxoma peritonei]

Pseudomyxoma peritonei is a clinical entity characterized by gelatinous ascites. It is most often due to a mucinous cystadenocarcinoma of the appendix or ovary. These patients die frequently of bowel obstruction after multiple surgical procedures. A case of pseudomyxoma peritonei treated successfully with intraabdominal infusion of a 2.5% solution of dextrose is reported.

Serum pepsinogen before and after proximal gastric vagotomy in duodenal ulcer treatment

Serum pepsinogen (SP) behavior was evaluated under basal conditions and under betazole stimulation in 59 patients: 14 controls, nine unoperated duodenal ulcers (DU) and 36 DU after proximal gastric vagotomy (PGV), 14 with and 22 without recurrent ulcer. The mean follow-up of the 36 patients who underwent PGV was 38.7 months. SP was higher in unoperated DU than in the control group (p less than 0.05). After PGV in DU, there is a significant decrease of SP for both the patients with and without recurrent ulcer (p less than 0.05), being statistically similar to the control group. No difference of SP was observed between DU with and without recurrent ulcer after PGV. We concluded that SP can differentiate normal subjects from DU patients, although it is not a sensitive indicator of recurrent ulcer after PGV.

[Enteral feeding of hospitalized neurologic patients: analysis of complications and nutritional results]

Patients with severe neurologic diseases submitted to enteral tube feeding were analyzed for four weeks. Initial and weekly assessment was done by laboratory and anthropometric data. Caloric requirements were calculated by the Harris-Benedict equation corrected for stress factors. The diet used provided 151 calories per gram of nitrogen, consisting of egg albumin, soy protein, maltodextrin, soy oil, medium-chain triglycerides, vitamin supplement, and mineral salts. Starting on the second week, there was a statistically significant correlation between caloric intake and caloric needs. In the same period, maintenance of lab parameters, worsening of the arm muscle circumference, and a trend to a positive nitrogen balance were observed. Diarrhea occurred in 14.5% of the patients. Enteral nutrition support for neurologic patients can be considered effective in the maintenance of the nutritional status. Careful daily monitoring is mandatory.