Effect of solvents on obligately anaerobic bacteria

Growth of Acetobacterium woodii and Clostridium sporogenes was studied in the presence of water-immiscible solvents. Nitrogen purging, vacuum distillation or distillation under nitrogen were all suitable as methods to remove oxygen from the solvents, since growth rates and yields of A. woodii were unaffected in the presence of tetradecane which had been degassed by these methods. Varying the solvent volume from 20% to 80% of the culture volume had little effect on growth rate of A. woodii. A.woodii was relatively sensitive to organic solvents since growth was inhibited by alkanes with logP(octanol/water) values below 7.1. C. sporogenes was less solvent sensitive, since it grew without inhibition when the logP of the solvent was > or = 6.6. Nevertheless, both A. woodii and C. sporogenes were more sensitive to solvent polarity than aerobic bacteria.     

Effects of nandrolone and resistance training on the blood pressure,cardiac electrophysiology,and expression of atrial β-adrenergic receptors

AimsThis study was performed to assess isolated and combined effects of nandrolone and resistance training on the blood pressure, cardiac electrophysiology, and expression of the β₁- and β₂-adrenergic receptors in the heart of rats.Main methodsWistar rats were randomly divided into four groups and submitted to a 6-week treatment with nandrolone and/or resistance training. Cardiac hypertrophy was accessed by the ratio of heart weight to the final body weight. Blood pressure was determined by a computerized tail-cuff system. Electrocardiography analyses were performed. Western blotting was used to access the protein levels of the β₁- and β₂-adrenergic receptors in the right atrium and left ventricle.Key findingsBoth resistance training and nandrolone induced cardiac hypertrophy. Nandrolone increased systolic blood pressure depending on the treatment time. Resistance training decreased systolic, diastolic and mean arterial blood pressure, as well as induced resting bradycardia. Nandrolone prolonged the QTc interval for both trained and non-trained groups when they were compared to their respective vehicle-treated one. Nandrolone increased the expression of β₁- and β₂-adrenergic receptors in the right atrium for both trained and non-trained groups when they were compared to their respective vehicle-treated one.SignificanceThis study indicated that nandrolone, associated or not with resistance training increases blood pressure depending on the treatment time, induces prolongation of the QTc interval, and increases the expression of β₁- and β₂-adrenergic receptors in the cardiac right atrium, but not in the left ventricle.     

Unveiling the social performance of selected agri-food chains in Costa Rica: the case of green coffee,raw milk and leafy vegetables

The International Journal of Life Cycle Assessment - Several frameworks coincide in the importance of addressing social impacts to ensure sustainability. However, the agri-food sector, regarded as...     

Use of polymethylmethacrylate as permanent filling agent in the jaw, mouth and face regions--implications for dental practice

doi: 10.1111/j.1741‐2358.2011.00479.x
Use of polymethylmethacrylate as permanent filling agent in the jaw, mouth and face regions – implications for dental practice Objectives: This article is a review of PMMA focusing on its properties, indications, contra‐indications and adverse effects. Background: The search to remain young is a constant attitude among Brazilians. The low cost of filling agents have stimulated its indiscriminate use, especially the bioplasty (non‐incisional method). Polymethylmethacrylate (PMMA) is the cosmetic filling agent of choice, because of its low cost, easy access and simple application technique. The impact on dentistry and orofacial medicine needs further awareness. Conclusion: The article aims to draw the attention of odontology and medical professionals to the product's applicability and its possible complications.     

Auxotrophic mutant of Staphylococcus aureus interferes with nasal colonization by the wild type

Staphylococcus aureus nasal carriage is a risk factor for infection in humans, particularly in the hospital setting. Bacterial interference was used as an alternative strategy for the prevention of upper respiratory, urogenital and gastrointestinal tract infections. This study was designed to assess if the administration of a live-attenuated aroA mutant of S. aureus is useful as a potential approach to prevent transient staphylococcal nasal carriage by virulent strains. We constructed an aroA mutant of S. aureus Newman strain by homologous recombination. The auxotrophic NK41 mutant was attenuated as determined by the increase of the LD(50) after intraperitoneal challenge. In mice, previous nasal colonization with the NK41 mutant significantly reduced the number of CFU of S. aureus (HU-71 and Hde288) clinical isolates and the parental Newman strain. The NK41 mutant was unable to induce a pro-inflammatory response and to damage the invaded human respiratory epithelial cells. Moreover, the cells previously or simultaneously infected with the NK41 mutant were invaded by virulent strains in a significantly lower degree than those of the control group. In conclusion, the attenuated NK41 mutant interfered with the colonization and establishment of pathogenic strains of S. aureus, which produce severe infections.     

Urinary Bladder Dysfunction in Transgenic Sickle Cell Disease Mice

Background

Urological complications associated with sickle cell disease (SCD), include nocturia, enuresis, urinary infections and urinary incontinence. However, scientific evidence to ascertain the underlying cause of the lower urinary tract symptoms in SCD is lacking.

Objective

Thus, the aim of this study was to evaluate urinary function, in vivo and ex vivo, in the Berkeley SCD murine model (SS).

Methods

Urine output was measured in metabolic cage for both wild type and SS mice (25-30 g). Bladder strips and urethra rings were dissected free and mounted in organ baths. In isolated detrusor smooth muscle (DSM), relaxant response to mirabegron and isoproterenol (1nM-10μM) and contractile response to (carbachol (CCh; 1 nM-100μM), KCl (1 mM-300mM), CaCl₂ (1μM-100mM), α,β-methylene ATP (1, 3 and 10 μM) and electrical field stimulation (EFS; 1-32 Hz) were measured. Phenylephrine (Phe; 10nM-100μM) was used to evaluate the contraction mechanism in the urethra rings. Cystometry and histomorphometry were also performed in the urinary bladder.

Results

SS mice present a reduced urine output and incapacity to produce typical bladder contractions and bladder emptying (ex vivo), compared to control animals. In DSM, relaxation in response to a selective β3-adrenergic agonist (mirabegron) and to a non-selective β-adrenergic (isoproterenol) agonist were lower in SS mice. Additionally, carbachol, α, β-methylene ATP, KCl, extracellular Ca²⁺ and electrical-field stimulation promoted smaller bladder contractions in SS group. Urethra contraction induced by phenylephrine was markedly reduced in SS mice. Histological analyses of SS mice bladder revealed severe structural abnormalities, such as reductions in detrusor thickness and bladder volume, and cell infiltration.

Conclusions

Taken together, our data demonstrate, for the first time, that SS mice display features of urinary bladder dysfunction, leading to impairment in urinary continence, which may have an important role in the pathogenesis of the enuresis and infections observed the SCD patients.     

Reduced Plasma Membrane H+-ATPase Isoform OsA7 Expression and Proton Pump Activity Decrease Growth Without Affecting Nitrogen Accumulation in Rice

Plasma membrane H⁺-ATPase (PM H⁺-ATPase, EC 3.6.1.3.) is a proton pump that is necessary to promote cell growth and ion fluxes across the plasma membrane. The main goal of this study was to evaluate the role of PM H⁺-ATPase isoform OsA7 expression in rice growth and nitrogen (N) accumulation using three genetically engineered lineages with artificial micro RNA (amiRNA) targeting OsA7 (osa7.1, osa7.2, and osa7.3). PM H⁺-ATPase isoform expression in rice shoots and roots (wild-type) revealed that OsA7 is highly expressed in roots and is the most highly expressed PM H⁺-ATPase isoform. The three osa7 lineages had lower fresh weight, grain yield, height, and 1000-grain weight compared to control IRS plants. The hydroponic experiment comprised three NO₃⁻ levels over 30 days: 0.2 mM NO₃⁻–N, 2.0 mM NO₃⁻–N, and NO₃⁻ starvation for 3 days. The three osa7 lineages had lower PM H⁺-ATPase and V-H⁺-PPase activity as compared to the IRS plants. The root and shoot fresh weights were lower in osa7 lineages. The root/shoot ratio was lower in the osa7 lineages cultivated without nitrogen for 3 days and with 0.2 mM of NO₃⁻–N as compared to IRS, and did not change in plants cultivated with 2.0 mM NO₃⁻–N. The total N concentration did not change in the three osa7 lineages as compared to IRS. Overall, the results indicate that OsA7 is important for rice growth, grain production, and root growth, but does not affect N accumulation, highlighting the importance of other PM H⁺-ATPase isoforms in N uptake.

     

Attenuation of capsaicin-induced acute and visceral nociceptive pain by alpha- and beta-amyrin, a triterpene mixture isolated from Protium heptaphyllum resin in mice

The triterpene mixture, alpha- and beta-amyrin, isolated from Protium heptaphyllum resin was evaluated on capsaicin-evoked nociception in mice. Orally administered alpha- and beta-amyrin (3 to 100 mg/kg) significantly suppressed the nociceptive behaviors--evoked by either subplantar (1.6 microg) or intracolonic (149 microg) application of capsaicin. The antinociception produced by alpha- and beta-amyrin against subplantar capsaicin-induced paw-licking behavior was neither potentiated nor attenuated by ruthenium red (1.5 mg/kg, s.c.), a non-specific antagonist of vanilloid receptor (TRPV1), but was greatly abolished in animals pretreated with naloxone (2 mg/kg, s.c.), suggesting an opioid mechanism. However, participation of alpha2-adrenoceptor involvement was unlikely since yohimbine (2 mg/kg, i.p.) pretreatment failed to block the antinociceptive effect of alpha- and beta-amyrin in the experimental model of visceral nociception evoked by intracolonic capsaicin. The triterpene mixture (3 to 30 mg/kg, p.o.) neither altered significantly the pentobarbital sleeping time, nor impaired the ambulation or motor coordination in open-field and rota-rod tests, respectively, indicating the absence of sedative or motor abnormality that could account for its antinociception. Nevertheless, alpha- and beta-amyrin could significantly block the capsaicin (10 mg/kg, s.c.)-induced hyperthermic response but not the initial hypothermia. These results suggest that the triterpene mixture, alpha- and beta-amyrin has an analgesia inducing effect, possibly involving vanilloid receptor (TRPV1) and an opioid mechanism.