Similar developmental fluctuations of hepato-renal xanthine oxidoreductase gene expression and xanthine oxidase activity in layer and broiler chicken embryos.

1. Xanthine oxidase (XO) has many physiological functions associated with the synthesis of both antioxidant (uric acid: UA) and numerous oxidants (e.g. H2O2), which makes it an important regulator of the cellular redox potential involving organogenesis. The ontogenetic study of hepatic and renal XO makes a better understanding of the putative role of this enzyme in the development of these tissues. 2. Developmental changes of gene expression of xanthine oxidoreductase (XOR), XO activity and UA content of liver and kidney tissues in both broiler and layer chicken embryos were examined during incubation d 14-21. 3. In both strains, hepatic XOR gene expression peaked on d 21 while renal XOR gene expression did not change. 4. The XO activity was higher in kidney than liver in both strains. Hepatic XO activity of both strains peaked on d 18 and thereafter was decreased on d 21. Renal XO activity peaked on d 18 and from then on did not show any significant changes until d 21 in both strains. 5. The UA content was higher in kidney vs. liver in both strains. The hepatic and renal UA values of the both strains increased significantly from d 14 to d 21. 6. The present results showed dissimilar behaviour of XOR gene expression, XO activity and UA content of liver and kidney tissues in both broiler and layer chicken embryos.

Diabetic kidney disease and vascular comorbidities in patients with type 2 diabetes mellitus in a developing country.

Type 2 diabetes mellitus (T2DM) is associated with an increased risk of progression toward end-stage renal disease and cardiovascular (CV) risk mortality. To investigate this association, we studied 637 patients with T2DM in the Eastern area of Morocco. The mean follow-up period was 42 ± 11 months. At the baseline visit, 22.8%, 59.1% and 18.1% of the patients had normo-albuminuria, micro-albuminuria and macro-albuminuria, respectively. Of all patients, 51.6% had a history of hypertension and 37.4% had hypertension on admission. At the end of follow-up, rapid progression (estimated glomerular filtration rate >5 mL/min/1.73 m² /year) was observed in 24.1% of the cases and the frequency of occurrence of CV events was 5%, 18.5% and 32.5% in the normo-, micro- and macro-albuminuria groups, respectively (P <0.001). In multivariate analysis, arterial hypertension was identified as an independent risk factor related to diabetic kidney disease (DKD, P = 0.04) and occurrence of CV events (P = 0.02), while albuminuria was not identified as an independent risk factor, either for DKD or for the occurrence of CV events. Our study found that hypertension was an independent risk factor for the DKD and the occurrence of the CV events in T2DM patients.

A genome-scale metabolic model of Methanococcus maripaludis S2 for CO2 capture and conversion to methane.

Methane is a major energy source for heating and electricity. Its production by methanogenic bacteria is widely known in nature. M. maripaludis S2 is a fully sequenced hydrogenotrophic methanogen and an excellent laboratory strain with robust genetic tools. However, a quantitative systems biology model to complement these tools is absent in the literature. To understand and enhance its methanogenesis from CO2, this work presents the first constraint-based genome-scale metabolic model (iMM518). It comprises 570 reactions, 556 distinct metabolites, and 518 genes along with gene-protein-reaction (GPR) associations, and covers 30% of open reading frames (ORFs). The model was validated using biomass growth data and experimental phenotypic studies from the literature. Its comparison with the in silico models of Methanosarcina barkeri, Methanosarcina acetivorans, and Sulfolobus solfataricus P2 shows M. maripaludis S2 to be a better organism for producing methane. Using the model, genes essential for growth were identified, and the efficacies of alternative carbon, hydrogen and nitrogen sources were studied. The model can predict the effects of reengineering M. maripaludis S2 to guide or expedite experimental efforts.

In silico modeling and evaluation of Gordonia alkanivorans for biodesulfurization.

The genus Gordonia is well known for its catabolic diversity and ability to transform several compounds including the various recalcitrant polyaromatic sulfur heterocycles (PASHs) found in the fossil fuels. In fact, some strains offer the unique ability to desulfurize even benzothiophene (BT) and other thiophenic compounds, which most of the commonly studied rhodococci strains cannot. In this work, we present the first genome scale metabolic model for G. alkanivorans, a desulfurizing strain, to enable a holistic study of its metabolism and comparison with R. erythropolis. Our model consists of 881 unique metabolites and 922 reactions associated with 568 ORFs/genes and 544 unique enzymes. It successfully predicts the growth rates from experimental studies and quantitatively elucidates the pathways for the desulfurization of the commonly studied sulfur compounds, namely dibenzothiophene (DBT) and benzothiophene (BT). Using our model, we identify the minimal media for G. alkanivorans, and show the significant effect of carbon sources on desulfurization with ethanol as the best source. Our model shows that the sulfur-containing amino acids such as cysteine and methionine decrease desulfurization activity, and G. alkanivorans prefers BT over DBT as a sulfur source. It also suggests that this preference may be driven by the lower NADH requirements for BT metabolism rather than the higher affinity of the transport system for BT. Our in silico comparison of R. erythropolis and G. alkanivorans suggests the latter to be a better desulfurizing strain due to its versatility for both BT and DBT, higher desulfurization activity, and higher growth rate.

Roles of sulfite oxidoreductase and sulfite reductase in improving desulfurization by Rhodococcus erythropolis.

Rhodococcus erythropolis has been widely studied for desulfurization. However, activity levels required for commercial application have not been achieved. A major limitation of the current work in biodesulfurization is inadequate information regarding sulfur metabolism generally, and in particular the metabolism of the sulfur obtained from dibenzothiophene (DBT) metabolism via the 4S pathway. In this work, we have investigated the possible routes taken by the sulfur from DBT to convert into biomass or other metabolites. We propose two alternate hypotheses. In the first, we hypothesize that the cell can convert via sulfite reductase (SR) the sulfite from the metabolism of DBT into sulfide that can be assimilated into biomass. However, in the process, it may convert any excess sulfite into extracellular sulfate via sulfite oxidoreductase (SOR) to avoid the toxic effects of sulfite. In the second, we speculate that the cell cannot assimilate the sulfite directly into biomass via SR. It must first use SOR to produce extracellular sulfate, and then recapture that sulfate into biomass via SR. Thus, either way, we propose that SOR and SR activities, in addition to dsz genes and cofactors, may be critical in increasing desulfurization levels significantly. In particular, we suggest that the simultaneous increase in SOR activity and decrease in SR activity can enable increased desulfurization activity.

Reconstruction of a genome-scale metabolic network of Rhodococcus erythropolis for desulfurization studies.

The remarkable catabolic diversity of Rhodococcus erythropolis makes it an interesting organism for bioremediation and fuel desulfurization. However, a model that can describe and explain the combined influence of various intracellular metabolic activities on its desulfurizing capabilities is missing from the literature. Such a model can greatly aid the development of R. erythropolis as an effective desulfurizing biocatalyst. This work reports the reconstruction of the first genome-scale metabolic model for R. erythropolis using the available genomic, experimental, and biochemical information. We have validated our in silico model by successfully predicting cell growth results and explaining several experimental observations in the literature on biodesulfurization using dibenzothiophene. We report several in silico experiments and flux balance analyses to propose minimal media, determine gene and reaction essentiality, and compare effectiveness of carbon, nitrogen, and sulfur sources. We demonstrate the usefulness of our model by studying a few in silico mutants of R. erythropolis for improved biodesulfurization, and comparing the desulfurization abilities of R. erythropolis with an in silico mutant of E. coli.

The effects of Cannabis sativa L. seed (hempseed) in the ovariectomized rat model of menopause.

Cannabis sativa L. has been used for the treatment of various gynecological diseases in traditional medicine. The potential of this plant to protect against complications of menopause has been raised but rarely studied. Twenty female rats were divided into five groups: sham-operated (sham), ovariectomized (OVX) and three other ovariectomized groups: HST1%, HST2% and HST10% which received 1%, 2% and 10% hempseed, respectively, in their diet for 3 weeks. The effects of hempseed on plasma lipid and lipoprotein profiles, estradiol and calcium levels were evaluated. Rats were tested for behavioral changes using the forced swimming test. The results showed that ovariectomy, independent of the type of diet, caused elevation of plasma calcium, total cholesterol and HDL-cholesterol levels, while hempseed modified this effect. Plasma estradiol levels were significantly lower in the OVX group compared to other groups. The swimming times for the OVX and sham groups were significantly shorter than that of the HSD10% group. All hempseed-treated groups were less anxious and showed significant declines in fecal boli compared to the sham group. The exploratory diving percent decreased in the HST10% group compared with other groups. These results suggest that hempseed may improve post-ovariectomy complications in rats.

Reactions of goldfish (Carassius auratus) to three suture patterns following full thickness skin incisions.

Three different suture patterns (simple interrupted, interrupted horizontal mattress, subcuticular) were placed in a full thickness incision (skin and body wall) of 18 goldfish (Carassius auratus). After 14 days all fish were euthanized using benzocaine solution. The tissue reactions were evaluated by gross visual inspection and histopathological examination. The superficial inflammatory reactions were graded on a scale from 0 (no inflammation) to 3 (severe inflammation). The inflammatory response in histological examination was graded on a scale from 0 (no inflammatory response or normal skin tissue) to 5 (severe inflammatory response and necrosis). The interrupted horizontal mattress induced a moderately severe to severe inflammatory response and necrosis (grades 4-5) but the subcuticular suture induced a very mild to mild inflammatory response (grades 0-1). The simple interrupted suture induced a moderate to moderately severe inflammatory response (grades 2-4). In conclusion, results showed that a subcuticular suture is the most appropriate to use in the closure of a full thickness body wall incision.

Effects of short-term cooling on pregnancy rate of dairy heifers under summer heat stress.

Thermal stress in cattle results in major decreases in dairy production and reproduction. A study was designed to evaluate the influence of temporary cooling on pregnancy rate in Holstein heifers during summer heat stress. Estrus was synchronized with two injections of prostaglandin [Formula: see text] (PG), administrated 11 d apart, and all heifers were housed in a shaded enclosed structure at the time of the second PG injection. After estrus detection, heifers were randomly divided into three groups: Control (C; n = 30), Sprinkler (S; n = 30) or Sprinkler and Fan (SF; n = 30). Rectal temperatures were measured 2.5 hours before AI, at the time of AI, and 1.5 and 3.5 hours after AI. Group C heifers receive no further treatment, but heifers in S and SF groups were exposed to short-term cooling from 2 hours before until 2 hours after AI with a sprinkler (S) or sprinkler and a fan (SF), respectively. Estrus detection and AI were performed by a single skilled technician; semen was from a bull of known fertility. Rectal temperature did not differ among groups 2.5 hours before AI, but at the time of AI was lower (P < 0.05) in SF group (39.3 +/- 0.0 degrees C) than in S (39.5 +/- 0.0 degrees C) and C (39.9 +/- 0.1 degrees C) groups which also differed (P < 0.05). At 1.5 and 3.5 hours after AI, rectal temperature remained lower in SF group (38.9 +/- 0.0 and 38.7 +/- 0.0 degrees C, respectively) than in the S (39.4 +/- 0.0 and 39.2 +/- 0.0 degrees C, respectively) and C (39.3 +/- 0.0 and 39.3 +/- 0.0 degrees C, respectively) groups, which no longer differed. Pregnancy rate following AI was higher (P < 0.05) in SF group (56.7%) than in the C group (23.3%) with the S group (40%) intermediate and not different from either. The present study results indicate that cooling of dairy heifers for a short time before and after AI, especially with sprinkler and fan, can increase pregnancy rate during heat stress.

Modeling and Monte Carlo simulation of TCDD transport in a river.

A one-dimensional water quality model to assess the long-term fate of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) in three compartments (water, sediment, fish) of a river has been developed using the literature data on various model parameters. The transient deterministic model with constant or nonrandom parameters is solved numerically by the method of orthogonal collocation, while an analytical solution is developed for the steady-state model. The impact of uncertainty in several model parameters has been studied by means of Monte Carlo simulations assuming that the uncertain parameters are uncorrelated and can be modeled by three probability distributions (uniform, normal and lognormal). For the case of a high TCDD discharge into a small, shallow river, we find that the maximum TCDD contents of water and fish are well below the prescribed safe limits. We also find that the effects of uncertainty on water quality metrics are quite complex or nonintuitive and can be substantial. This is especially true for TCDD in fish, which can be higher by as much as 50-70% than the deterministic predictions, if the parameter uncertainties follow uniform distributions.