Groundwater Pollution in a Karstic Region (NE Yucatan): Baseline Nutrient Content and Flux to Coastal Ecosystems

The quality of groundwater is threatened in karstic regions with very high population growth, such as the eastern coast of Yucatan. As polluted groundwater flows towards the ocean, coastal ecosystems and coral reefs may also be affected. Pollution and the interaction between the coastal aquifer and the reef lagoon were assessed at a developing area (Puerto Morelos, NE Yucatan Peninsula) within the Mesoamerican Coral Reef System. Coastal environments along the land?Csea gradient (wells, mangroves, beaches, submarine springs, the reef lagoon, and the open sea) were sampled. Silicate and salinity were used as tracers of groundwater and seawater, respectively. Their patterns evidence water flow and mixing among these coastal environments. High nitrate concentrations (268.6 ??M) and coliform bacteria densities indicate groundwater pollution in most of the wells sampled and also in mangroves, beaches, and submarine springs. Phosphorous content peaks (14.2 ??M) in mangroves, where it is likely released due to reducing conditions in the sediments. Nitrogen flux toward the lagoon reef through groundwater discharge is estimated at 2.4 ton N km^?1 year^?1 and phosphorous at 75 to 217 kg P km^?1 year^?1. These results provide evidence of the need for more detailed groundwater studies and for the integrated management of aquifers and coastal ecosystems in karstic regions.     

Antioxidant Properties of Fermented Soy during Shelf Life

Plant Foods for Human Nutrition - Glycine max (soybean) is a fundamental food in human nutrition, largely utilized by the consumers, and in particular, fermented soy is mainly used. However, health...     

“Subnutrition effects during pregnancy and lactation on mitosis,apoptosis and androgen receptor expression in the rat testis”

In order to study the effect of undernutrition during gestation on the testicular development in rats and its impact on mitosis, apoptosis and the relative abundance of androgen receptor expression, twenty primiparous 3‐month‐old Sprague–Dawley (Rattus norvegicus) rats, weighing 246 ± 4.0 grams when the experiment began, were mated by the same male. Control group (CG), n = 10, fed ad libitum with water and rat chow and restricted group (RG, n = 10) fed throughout pregnancy and until birth with 40% of the ad libitum maternal daily feed intake. Litters from both groups suckled for 25 days, RG with 14 pups/litter and CG with 8 pups/litter. After weaning, all animals had access to ad libitum food and water. Testicular samples were taken from male pups at 2, 25 and 100 days of age. Immunohistochemistry was used to evidence androgen receptor (AR) expression in apoptotic (caspase 3‐positive) and proliferating (PCNA‐positive) cells. Three hundred nuclei of sustentacular (or Sertoli: SC), interstitial (or Leydig: LC), myoid (MC) cells as well as gonocytes (GC) were evaluated. Neither LC nor GC showed any differences between groups. However, SC androgen receptor (AR) positivity index in neonatal animals was lower in RG (1.27 ± 0.22 vs. 1.65 ± 0.17**). MC showed lower AR positivity index at 2 (2.69 ± 0.046 vs. 2.8 ± 0.055**) and 25 (1.34 ± 0.097 vs. 1.56 ± 0.1***) days of life; at 100 days of life, there was a greater number of apoptotic MC in the RG (8.5 ± 0.4 vs. 2.95 ± 1.1***). Thus, the present experiment demonstrates that the population dynamics of MC are affected by foetal programming due to undernutrition.     

Responses to selection and changes in combining ability after three cycles of a modified reciprocal recurrent selection in maize

This research reports responses to selection and changes in general (GCA) and specific (SCA) combining abilities after three cycles of a modified reciprocal recurrent selection procedure (MRRS) in EPB-4 and EPB-5 maize populations. In the MRRS procedure a cycle can be completed in 1 or 2 years depending on the availability of winter breeding nurseries. The original and the three selection cycles of the two populations per se (eight entries) and the partial diallel developed from the crosses between them (16 entries) were evaluated in six environments. Realized response to selection on the population cross was 7.25% cycle⁻¹ for grain yield, −13.63% cycle⁻¹ for plant lodging, and 11.93% cyle⁻¹ for prolificacy, whereas plant and ear heights remained unchanged. GCA estimates increased with selection cycles for both populations for grain yield and prolificacy, and decreased for plant lodging, indicating that the frequency of favorable alleles with additive effects for these traits increased with the MRRS cycles in both populations. SCA estimates increased for grain yield and prolificacy indicating that the frequency of favorable complementary alleles at loci with non-additive effects in the reciprocal populations increased with the MRRS cycles. For grain yield, SCA effects increased more than GCA effects with selection cycles, indicating that MRRS exploited more the non-additive effects than the additive effects for the improvement of this trait. The overall results showed that the MRRS procedure was highly effective in improving the population cross, exploiting both GCA and SCA effects.     

Use of Adipose Tissue-Derived Mesenchymal Stem Cells for Experimental Tendinitis Therapy in Equines

Superficial digital flexor tendon lesion is an important cause of lameness in equine athletes. Although numerous treatments have been described, few are effective at promoting significant improvement in the quality of the extracellular matrix. Therefore, great potential remains for recurrence and in certain cases, an abrupt end to the horse’s athletic career. Recently, several experiments have focused on the therapeutic potential of mesenchymal stem cells (MSCs) in cases of tendon lesions. This study aimed to evaluate the effect of adipose tissue-derived MSCs in the treatment of induced tendinitis of the superficial digital flexor tendon in horses by clinical, ultrasonographic, histopathological, and immunochemical analyses. Tendinitis was induced in both thoracic limbs of eight mares by administration of collagenase solution and adipose tissue was collected from the tail base for MSCs isolation and expansion, which were used during cellular therapy on only one limb 30 days after lesion induction. No differences occurred between the groups regarding the clinical and ultrasonographic analyses; however, histopathological evaluation revealed a significant improvement in tendon fiber organization and diminished inflammatory infiltrate, whereas immunohistochemical analysis showed increased expression of type I collagen in the treated group as compared with controls. The cellular therapy model implanted in this experiment promoted increased perivascular inflammatory infiltrate, fibroblastic density, neovascularization, and qualitative healing improvement of tendon extracellular matrix, in terms of fiber orientation and type I/III collagen ratio; moreover, it was considered to be a safe and viable process.     

Use of electronic nose technology to measure soil microbial activity through biogenic volatile organic compounds and gases release

Gas and volatile organic compounds (VOCs) release in soil is known to be linked to microbial activity and can differently affect the life of organisms in soil. Electronic noses (E-noses) are sensing devices composed of sensor arrays able to measure and monitor gases and VOCs in air. This is the first report on the use of such a sensing device to measure specifically microbial activity in soil. In the present study, γ-irradiated sterilised soil was inoculated with Pseudomonas fluorescens. To be sure for a rapid microbial growth and activity, two pulses of nutrient solution with organic and inorganic C, N, P and S sources were added to soil and the resulting microcosms were incubated for 23 d. During the incubation, respiration and enzyme activities of acid phosphatase, β-glucosidase, fluorescein diacetate hydrolase and protease, were measured, and microbial growth as global biomass of vital cells based on substrate-induced respiration (SIR-C_mic) and enumeration of viable and culturable cells by means of dilution plate counts (CFU) were also monitored. Concurrently, VOCs and/or gas evolution in the headspace of the soil microcosms were measured through the E-nose, upon their adsorption on quartz crystal microbalances (QCMs) comprising the sensory device. The E-nose typically generated an odorant image (olfactory fingerprint) representative of the analysed samples (soils) and resulting from the concurrent perception of all or most of the analytes in headspace, as it commonly happens when several selective but not specific sensors are used together (array). The basic hypothesis of this study was that different soil ecosystems expressing distinct microbial metabolic activities, tested through respiration and enzyme activities, might generate different olfactory fingerprints in headspace. Furthermore, the possibility to detect several substances at the same time, released from the soil ecosystems, possibly deriving from both abiotic and biotic (microbial metabolism) processes provides an “odorant image” representative of the whole ecosystem under study. The E-nose here used succeeded in discriminating between inoculated and non-inoculated ecosystems and in distinguishing different metabolic and growth phases of the inoculated bacteria during incubation. Specifically, E-nose responses were proved highly and significantly correlated with all hydrolytic activities linked to the mobilisation of nutrients from soil organic matter and their cycling, with CO₂ fluxes (respiration and presumed heterotrophic fixation) and with P. fluorescens population dynamics during exponential, stationary and starvation phases measured by SIR-C_mic and CFUs. Interestingly, the E-nose successfully detected soil microbial activity stimulated by nutrient supply, even though none of the catalytic activities tested directly produced VOCs and/or gases. The E-nose technology was then proved able to supply a real holistic image of microbial activity in the entire gnotobiotic and axenic soil ecosystems.     

Antitumor Potential of Immunomodulatory Natural Products

Cancer is one of the leading causes of death globally. Anticancer drugs aim to block tumor growth by killing cancerous cells in order to prevent tumor progression and metastasis. Efficient anticancer drugs should also minimize general toxicity towards organs and healthy cells. Tumor growth can also be successfully restrained by targeting and modulating immune response. Cancer immunotherapy is assuming a growing relevance in the fight against cancer and has recently aroused much interest for its wider safety and the capability to complement conventional chemotherapeutic approaches. Natural products are a traditional source of molecules with relevant potential in the pharmacological field. The huge structural diversity of metabolites with low molecular weight (small molecules) from terrestrial and marine organisms has provided lead compounds for the discovery of many modern anticancer drugs. Many natural products combine chemo-protective and immunomodulant activity, thus offering the potential to be used alone or in association with conventional cancer therapy. In this review, we report the natural products known to possess antitumor properties by interaction with immune system, as well as discuss the possible immunomodulatory mechanisms of these molecules.