Disposición y tamaño de los desechos sólidos en el proceso de biodegradación aeróbica

En el Núcleo “Rafael Rangel” de la Universidad de Los andes en Trujillo se colectaron restos de poda de grama, desechos sólidos orgánicos frescos del comedor universitario y estiércol de bovinos que sirvieron como materia prima para la elaboración de ocho pilas de compost.  Cuatro se elaboraron siguiendo la metodología “indore” que consistió en la colocación de capas alternas de los materiales señalados hasta alcanzar una altura de 1,50m, en las otras cuatro pilas los materiales los fueron picados y mezclados homogéneamente antes de la construcción de las mismas; los tratamientos se distribuyeron aleatoriamente.  Durante el proceso se controló la humedad, se registró la temperatura diariamente y se efectuaron volteos de los montones según la evolución de la temperatura, tomando muestras para determinar pH, conductividad eléctrica (CE), carbono y nitrógeno total.  Los compost elaborados fueron secados, tamizados y caracterizados determinando, además  de las variables señaladas, el índice de humificación, la capacidad de intercambio catiónico (CIC), densidad aparente y distribución del tamaño de partículas. Para evaluar la diferencia entre los valores promedio obtenidos se aplicó la prueba t de significación estadística.  Los resultados señalan que hubo efecto  de la forma en que se colocaron los materiales y de la reducción del tamaño de las partículas en la biodegradación de los desechos, solamente en las variables pH y conductividad eléctrica.Palabras clave: compost, desechos, reciclaje, degradación, mezclas. AbstractIn the Nucleo Rafael Rangel of the University of Los Andes in Trujillo, six compost piles were built using grass clippings, fresh solid organic wastes from the university cafeteria, and bovine manure as raw materials. Three of the piles were prepared following the indore method that involved stacking alternate layers of those materials to a height of about 1.50 m. For the other three piles, the materials were chopped and mixed homogeneously before they were made. During the decomposition period, the compost pile moisture was controlled, temperature was daily registered, and aeration by turning the heaps was kept under control according to the evolution of the process.  Samples were taking to measure pH, electric conductivity, carbon, and total nitrogen. The finished composts were dried, screened, and characterized to determine the humification index, cation exchange capacity, bulk density and particle size distribution. The results indicated that neither the way in which the materials were stacked, nor the reduction in particle size had significant effect on biodegradation of the waste materials. The results showed that there was significant effect on the form that the solid wastes were disposed and of the particle size of the material just with the pH and the electrical conductivity variables.Index words: composting, wastes, recycling, degradation, mixs.&nbsp

Modulation of suicidal erythrocyte cation channels by an AMPA antagonist

n neurons alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptors are heteromeric cation channels composed of different sub-units, including GluA1-GluA4. When expressed without GluA2, AMPA receptors function as Ca(2+)-permeable cation channels. In erythrocytes, activation of Ca(2+)-permeable cation channels triggers suicidal erythrocyte death or eryptosis, which is characterized by cell shrinkage and cell membrane scrambling with subsequent exposure of phosphatidylserine at the cell surface. Activators of the channels and thus eryptosis include removal of extracellular Cl(-) (replaced by gluconate) and energy depletion (removal of glucose). The present study explored whether GluA1 is expressed in human erythrocytes and whether pharmacological AMPA receptor inhibition modifies Ca(2+) entry and suicidal death of human erythrocytes. GluA1 protein abundance was determined by confocal microscopy, phosphatidylserine exposure was estimated from annexin V binding, cell volume from forward scatter in FACS analysis, cytosolic Ca(2+) concentration from Fluo3 fluorescence and channel activity by whole-cell patch-clamp recordings. As a result, GluA1 is indeed expressed in the erythrocyte cell membrane. The AMPA receptor antagonist NBQX (1,2,3,4-tetrahydro-6-nitro-2,3-dioxo-benzo[f]quinoxaline-7-sulfonamide) inhibited the cation channels following Cl(-) removal and the eryptosis following Cl(-) removal or energy depletion. The present study reveals a novel action of AMPA receptor antagonists and raises the possibility that GluA1 or a pharmacologically related protein participates in the regulation of Ca(2+) entry into and suicidal death of human erythrocytes

Cancer detection and complications in transperineal prostate biopsy, with antibiotics only when indicated

Objectives: To describe the prostate cancer (PCa) detection rate, including clinically significant prostate cancer (csPCa), in a large cohort of patients who underwent transperineal ultrasonography-guided systematic prostate biopsy (TPB-US) using a probe-mounted transperineal access system, with magnetic resonance imaging (MRI) cognitive fusion in case of a Prostate Imaging–Reporting and Data System grade 3–5 lesion, under local anaesthesia in an outpatient setting. Additionally, to compare the incidence of procedure-related complications with a cohort of patients undergoing transrectal ultrasonography-guided (TRB-US) and transrectal MRI-guided biopsies (TRB-MRI). Patients and Methods: This was an observational cohort study in men who underwent TPB-US prostate biopsy in a large teaching hospital. For each participant, prostate-specific antigen level, clinical tumour stage, prostate volume, MRI parameters, number of (targeted) prostate biopsies, biopsy International Society of Uropathology (ISUP) grade and procedure-related complications were assessed. csPCa was defined as ISUP grade ≥2. Antibiotic prophylaxis was only given in those with an increased risk of urinary tract infection. Results: A total of 1288 TPB-US procedures were evaluated. The overall detection rate for PCa in biopsy-naive patients was 73%, and for csPCa it was 63%. The incidence of hospitalization was 1% in TPB-US (13/1288), compared to 4% in TRB-US (8/214) and 3% in TRB-MRI (7/219; P = 0.002). Conclusions: Contemporary combined systematic and target TPB-US with MRI cognitive fusion is easy to perform in an outpatient setting, with a high detection rate of csPCa and a low incidence of procedure-related complications

Delineating MT-ATP6-associated disease.

ObjectiveTo delineate the phenotypic and genotypic spectrum in carriers of mitochondrial MT-ATP6 mutations in a large international cohort.MethodsWe analyzed in detail the clinical, genetical, and neuroimaging data from 132 mutation carriers from national registries and local databases from Europe, USA, Japan, and China.ResultsWe identified 113 clinically affected and 19 asymptomatic individuals with a known pathogenic MT-ATP6 mutation. The most frequent mutations were m.8993 T > G (53/132, 40%), m.8993 T > C (30/132, 23%), m.9176 T > C (30/132, 23%), and m.9185 T > C (12/132, 9%). The degree of heteroplasmy was high both in affected (mean 95%, range 20%-100%) and unaffected individuals (mean 73%, range 20%-100%). Age at onset ranged from prenatal to the age of 75 years, but almost half of the patients (49/103, 48%) became symptomatic before their first birthday. In 28 deceased patients, the median age of death was 14 months. The most frequent symptoms were ataxia (81%), cognitive dysfunction (49%), neuropathy (48%), seizures (37%), and retinopathy (14%). A diagnosis of Leigh syndrome was made in 55% of patients, whereas the classic syndrome of neuropathy, ataxia, and retinitis pigmentosa (NARP) was rare (8%).ConclusionsIn this currently largest series of patients with mitochondrial MT-ATP6 mutations, the phenotypic spectrum ranged from asymptomatic to early onset multisystemic neurodegeneration. The degree of mutation heteroplasmy did not reliably predict disease severity. Leigh syndrome was found in more than half of the patients, whereas classic NARP syndrome was rare. Oligosymptomatic presentations were rather frequent in adult-onset patients, indicating the need to include MT-ATP6 mutations in the differential diagnosis of both ataxias and neuropathies