Anaerobic digestion of cheese whey: Energetic and nutritional potential for the dairy sector in developing countries.

Cheese whey (CW) is the main waste generated in the cheesemaking process and has high organic matter content and acidity. Therefore, CW disposal is a challenge for small to medium enterprises (SMEs) in the dairy industry that do not have any type of treatment plant. Anaerobic digestion (AD) is an attractive process for solving this problem. The aim of this research was to determine the biomethane and struvite precipitation potentials of CW from four dairy SMEs. First, changes in CW properties (organic matter and pH) were evaluated. Second, biomethane and struvite potentials were assessed using cattle slurry as inoculum. The organic matter in CW varied from 40 to 65gVS/kg, 65 to 140g COD/L, and 2 to 10g/L for VFAs depending on the sampling time and type of sample. The pH of the CW samples ranged from 3 to 6.5. In the anaerobic biodegradability analysis, methane yields reached 0.51 to 0.60L CH4/g VSadded, which represented electrical and caloric potentials of 54 and 108kWh/m3 for CW, respectively. Organic matter removal in all experiments was above 83%. Moreover, anaerobic digestates presented NH4+/PO43- molar ratios between 2.6 and 4.0, which are adequate for struvite precipitation with potential production of 8.5-10.4g struvite/L CW. Finally, the use of biogas as energetic supplement and struvite as soil fertilizer, represents economics saves of US$ 6.91/m3 CW and US$ 5.75/m3 CW in therms of electricity and fertilizer use, respectively. The energetic, agricultural and economic potentials, evidence that AD process is a feasible alternative for cheese whey treatment.

The role of endocannabinoids in pain modulation and the therapeutic potential of inhibiting their enzymatic degradation.

The need for new pain therapies that provide greater relief without unwanted side-effects drives the search for new drug targets. The identification of endogenous lipid ligands for the two known cannabinoid receptors (CB(1) and CB(2)) has led to numerous studies investigating the role of these endocannabinoids in pain processes. The two most widely studied endocannabinoids are anandamide (AEA; arachidonoyl ethanolamide) and 2-arachidonoylglycerol (2-AG), but there are also a number of structurally related endogenous lipid signaling molecules that are agonists at cannabinoid and noncannabinoid receptors. These lipid signaling molecules are not stored in synaptic vesicles, but are synthesized and released on-demand and act locally, as they are rapidly inactivated. This suggests that there may be therapeutic potential in modulating levels of these ligands to only have effects in active neural pathways, thereby reducing the potential for side-effects that result from widespread systemic cannabinoid receptor activation. One approach to modulate the levels and duration of action of these lipid signaling molecules is to target the enzymes responsible for their hydrolysis. The two main enzymes responsible for hydrolysis of these lipid signaling molecules are fatty acid amide hydrolase (FAAH) and monoacylglyceride lipase (MGL). This article will discuss the role of the endocannabinoid system in the modulation of pain and will review the current understanding of the properties of the hydrolytic enzymes and the recent advances in developing inhibitors for these targets, with particular relevance to the treatment of pain.

Niveles de hemoglobina glicosilada como predictor de control metabólico: en diabéticos que acudieron al Hospital "Dr. Patrocinio Peñuela Ruíz" y consulta privada San Cristóbal, estado Táchira: marzo-mayo 2007 / Hemoglobin glycosylated levels as a predictor of metabolic control: in diabetics attending the Hospital Dr. Patrocinio Peñuela Ruíz and private consultation San Cristobal, state Táchira: march-may 2007

Se determinaron niveles de hemoglobina glicosilada (HbA1c) como parámetro de control metabólico en diabéticos hospitalizados o en consulta en el Hospital del Seguro Social y medio privado, como parte de estudio multicentrico de OMS para conocer este parámetro en los venezolanos. Se analizó el número de diabéticos atendidos, los niveles de HbA1c, sexo, tipo de tratamiento e índice de masa corporal (IMC). Se atendieron 124 diabeticos, 48 hombres (38,70 por ciento) y 76 mujeres (61,29 por ciento), 7 eran diabéticos tipo 1 y 117 diabéticos tipo 2, encontrándose niveles promedio HbA1c 8,5 por ciento, IMC 29,7. Se concluye que el análisis de HbA1c permite evaluar el control metabólico de los pacientes diabéticos, evidenciándose mal control en el grupo estudiado. Se hace necesario ajustes en estrategias de control en estos pacientes.

Dissociation of the effect of spatial behaviors on the phosphorylation of cAMP-response element binding protein (CREB) within the nucleus accumbens.

Several studies have reported a role for the nucleus accumbens (NAcc) in learning and synaptic plasticity. Many of them suggest that the NAcc is involved in translating cortico-limbic information to the motor system mediating spatial learning and memory processes. Previous studies from our laboratory have shown that protein kinase C is activated following training in a food search spatial learning task. The present study further characterizes the molecular substrates associated with NAcc-dependent spatial behavior. The cyclic AMP-response element binding protein (CREB), a transcription factor implicated in the formation of long-term memory, was studied in the NAcc following spatial training in a food search spatial learning task. Western blots were performed to detect phosphorylated (activated) and total CREB protein levels. Our results show that CREB is significantly phosphorylated in the NAcc 48 h after habituation and at 5 min and 1 h after the first spatial training session in comparison with the naive animals that remained in their home cages. Since published data show that NAcc plays a role in novelty detection and reactivity, we conducted further experiments in order to dissociate the effect on CREB phosphorylation and expression of spatial novelty (single exposure), exploration, and spatial learning in the food search apparatus. Results show that CREB phosphorylation is significantly increased 48 h after exposure to a novel environment. The present study suggests that CREB phosphorylation observed in the NAcc during habituation and spatial training may be mainly triggered by detection of spatial novelty.

Evaluation of the polymerase chain reaction in the diagnosis of miliary tuberculosis in bone marrow smear.

OBJECTIVE: Miliary tuberculosis (MTB) is difficult to diagnose. When prompt diagnosis is necessary, the polymerase chain reaction (PCR) to detect mycobacterial DNA may be valuable. SETTING: Tuberculosis clinic in an academic tertiary-level hospital in Mexico. DESIGN: Bone marrow (BM) aspiration samples from 30 consecutive clinically suspected MTB patients and 58 non-tuberculosis hematologic patients were evaluated by in-house PCR using a fragment of the insertion sequence IS6110; results were compared with those obtained by acid-fast-stained smears, culture in Löwenstein-Jensen medium, histology, and serology. RESULTS: Tuberculosis diagnosis was confirmed in all MTB suspects, 28 by microscopy and culture in pulmonary or extra-pulmonary samples other than BM, and two by clinical and radiologic improvement after antituberculosis treatment. In fresh BM specimens, in-house PCR was positive in 21/30 (70%) suspects, contrasting with only one positive (3.3%) in staining and culture, and four with compatible histologic findings (13.3%). BM samples from the control group showed negative results in bacteriologic and histologic studies, except in nine who had positive PCR results. These nine control cases had malignant processes. CONCLUSION: PCR in aspirates of BM is a useful diagnostic assay in cases of MTB, mainly when bacteriological results are negative.

Propane and butane emission sources to ambient air of Mexico City metropolitan area.

Samples of volatile organic compounds (VOCs) were collected in a smog chamber in order to determine whether automotive exhausts or LP Gas emissions play a greater role in the source of propane and butane, which affect ozone formation and other pollutants in the ambient air of the Mexico City metropolitan area (MCMA). These samples were collected in April 1995 during mornings and evenings. The testing methodology used for measuring exhaust emission were FTP or EPA-74 tests, and SHED type tests were also conducted in order to evaluate evaporative emissions. The finding from analysis of the VOCs collected in the morning demonstrate that in the atmosphere, propane concentrations are higher than that of butane but the reverse in evaporative and exhaust emissions, with the concentration of propane lower than that of butane. Our conclusion is that most of C3 and C4 in the ambient air comes from LP gas and not vehicle exhaust or evaporative emission, due to the higher levels of propane than butane in its formulation. The analysis of VOCs also indicates that although the conversion (in the smog chamber) of alkanes is low during the day, due to the high initial concentration, their contribution in the reaction mechanism to produce ozone can be appreciable.