16S metabarcoding analysis reveals the influence of organic and conventional farming practices on bacterial communities from the rhizospheric of Coffea arabica L.

Coffea sp. is cultivated in many tropical countries. Brazil has always adopted intensive agricultural practices, but organic coffee farming is an alternative system based on the non-use of agrochemicals and the rational management of soils. Metabarcoding 16S analysis using next-generation sequencing has been developed to identify and compare the diversity of the Coffea arabica L. rhizospheric bacterial community in two farming areas in São Paulo, Brazil. Dourado uses conventional farming, while Ribeirão Corrente uses organic. We found broad taxonomic composition, with sequences from 24 phyla, 55 classes, 61 orders, 146 families, and 337genus. The three most abundant phyla were Proteobacteria (38.27%), Actinobacteria (15.56%), and Acidobacteria (16.10%). In organic farming, the top 3 were the family Sphingomonadaceae, order Rhizobiales, genus Nocardioides, and Gp6. The genus Gp2 and the phylum Candidatus Saccharibacteria were the most abundant OTUs exclusively present in conventional farming. In the organic farming practice, Proteobacteria, Actinobacteria, and Acidobacteria were also present among the exclusive OTUs; we also found OTUs belonging to Bacteroidetes, Firmicutes, and Verrucomicrobia. Our study indicates a positive effect of organic farming on microbial communities. Fertilization may directly affect soil microbiota, suggesting that a large and active microbial community low in functional diversity might not adapt to new climatic conditions. A diverse community could provide better resilience to environmental changes, improving the productivity of this important crop.

Expression profiles of neotropical termites reveal microbiota-associated, caste-biased genes and biotechnological targets.

Termites are well recognized by their complex development trajectories, involving dynamic differentiation process between non-reproductive castes, workers and soldiers. These insects are associated with endosymbiotic microorganisms, which help in lignocellulose digestion and nitrogen metabolism. Aiming to identify genes harbouring biotechnological potential, we analyzed workers and soldiers RNA-Seq data of three neotropical termites: Heterotermes tenuis (Isoptera: Rhinotermitidae), Velocitermes heteropterus (Isoptera: Termitidae) and Cornitermes cumulans (Isoptera: Termitidae). We observed differences in the microbiota associated with each termite family, and found protists' genes in both Termitidae species. We found an opposite pattern of caste-biased gene expression between H. tenuis and the termitids studied. Moreover, the two termitids are considerably different concerning the number of differentially expressed genes (DEGs). Functional annotation indicated considerable differences in caste-biased gene content between V. heteropterus and C. cumulans, even though they share similar diet and biological niche. Among the most DEGs, we highlighted those involved in caste differentiation and cellulose digestion, which are attractive targets for studying more efficient technologies for termite control, biomass digestion and other biotechnological applications.

Effect of preinjury large bowel emptying on the inhibition of upper gastrointestinal motility after spinal cord injury in rats.

Spinal cord transection (SCT) inhibits gastrointestinal motility in rats. We evaluated the effect of preinjury large bowel emptying on this phenomenon. Male Wistar rats (N = 52) were fasted for 24 or 48 hr with water ad libitum and pretreated with lactose (0.8 g) or saline. Next, laminectomy followed or not by complete SCT between T4 and T5 vertebrae was performed. Phenol red recovery in the stomach and proximal, medial, and distal small intestine was determined 1 day later. In animals submitted to 24 hr fasting + saline, SCT increased gastric recovery by 42.8% and decreased medial small intestine recovery by 56.2%, while 48 hr fasting + saline or 24 hr fasting + lactose prevented the inhibition of gastric emptying (GE) in SCT animals. The 48 hr fasting + lactose prevented the inhibition of both GE and gastrointestinal transit. SCT-induced inhibition of upper gastrointestinal motility may involve enhancement of inhibitory reflexes, which can be prevented by large bowel emptying.

Extracts of Anacardium occidentale (cashew) pollen in patients with allergic bronchial asthma.

Allergic reactions to the pollen of trees is among the most prevalent allergic sensitivities. The cashew tree grows in abundance in the northeast region of the Brazil, mainly in Fortaleza city, in state of the Ceará. It flowers once a year between August and October. This is the first study conducted to establish the possible role of the cashew pollen extract in causing skin test reactivity in patients with allergic asthma. A stock solution of pollen extract was prepared with the standard weight/volume method for intradermal skin tests and for the protein content of the extract, estimated with the use of Folin phenol reagent and a spectrophotometer. Ten nonallergic volunteers and 80 subjects with allergic asthma, as documented by previous positive skin test reactions to various pollens, were studied. All of the 80 patients (100%) had positive test reactions (grade III and grade IV reactions). None of the control subjects (n = 10) had positive responses to the intradermal tests. This study provided us with knowledge of an additional pollen extract of the Anacardium occidentale, which could provoke skin test reactivities in asthmatic individuals from the northeastern area of Brazil. The results suggest a relationship between the period of flowering of the cashew tree and the increased number of allergic asthma cases.

Gastric emptying and gastrointestinal transit of liquid throughout the first month after thoracic spinal cord transection in awake rats.

Spinal cord transection (SCT) inhibits gastrointestinal motility in awake rats. We studied the gastric emptying (GE) and gastrointestinal transit of liquid throughout the first month after thoracic SCT. Male Wistar rats (N = 66) were submitted to laminectomy followed or not by complete SCT between T4 and T5 vertebrae. Phenol red recovery in the stomach, proximal, mid-and distal small intestine was determined 1, 7, 10, 15, and 30 days thereafter. Gastric recovery increased by 51.2 and 38.9% and mid-intestinal recovery decreased by 45.5 and 66.6% at one and seven days after SCT (P < 0.05). Proximal small intestine recovery increased by 45.9% 10 days after SCT but no inhibition of gastrointestinal motility was observed thereafter. Stool output significantly decreased in the first seven days after SCT (P < 0.05). In summary, gastrointestinal motility in awake rats is inhibited throughout the first 10 days after thoracic SCT but not thereafter.