Development of a novel clinimetric tool: PAtient Reported Disease Activity Index in Rheumatoid Arthritis (PARDAI-RA) by PANLAR, for the assessment of patients living with rheumatoid arthritis

BACKGROUND

Clinical experience has shown that a single measure is not sufficient to assess disease activity in rheumatoid arthritis (RA). Various clinimetric tools are necessary to address the many clinical situations that can arise.

METHODS

In order to develop a comprehensive measurement tool, the Pan American League of Associations for Rheumatology searched for the most frequent measures of disease activity applied in RA by means of a semi-systematic review of the available literature.

RESULTS

We found that the most frequently reported measures of disease activity were the 28-joint Disease Activity Score, C-reactive protein, and the erythrocyte sedimentation rate, followed by patient-reported measures of pain and stiffness and many other composite indices and patient-reported outcome measures. The most frequent physician-reported sign of disease was the swollen joint count, and the most frequently self-reported feature was the increase in disease activity or flares.

CONCLUSION

In this article, we present a new clinimetric tool developed based on expert consensus and on data retrieved from our search. Disease activity can be better assessed by combining various data sources, such as clinical, laboratory, and self-reported outcomes. These variables were included in our novel clinimetric tool. Key Points • The goal of treatment of RA is to achieve the best possible control of inflammation, or even remission; therefore, disease management should include systematic and regular evaluation of inflammation and health status. • Clinimetric tools evaluate a series of variables (e.g., symptoms, functional capacity, disease severity, quality of life, disease progression) and can reveal substantial prognostic and therapeutic differences between patients. • Our clinimetric tool, which is based on a combination of data (e.g., clinical variables, laboratory results, PROMs), can play a relevant role in patient assessment and care.

Surgical management of congenital malrotation presenting in adulthood

Intestinal malrotation is characterised by positional and congenital fixation abnormalities resulting from a failure in embryonic development in the normal 270° rotation around the axis of the superior mesenteric artery. Intestinal malrotation is primarily thought to affect neonates with an incidence of 1 in 500, however, only 1 in 6000 live births are symptomatic, and these usually present within the first month of life in 40% of cases and within the first year in over 5% of cases as an obstructive pathology or volvulus. In adults, however, the incidence has been documented at 0.2%. These patients usually present with postprandial symptoms that are intermittent such as bilious emesis, abdominal pain and malabsorption. Rarely, adults with congenital malrotation may present with acute obstruction due to volvulus, however, less than 100 adult cases are described in the literature. A high index of suspicion is required to identify cases of malrotation in the adult patient which leads to delays in diagnosis and therefore increases in morbidity can be seen.

A case report of acute appendicitis complicated by pylephlebitis: medical and surgical management

Pylephlebitis is a suppurative thrombus of the portal vein and/or its branches secondary to an intra-abdominal infection. Acute appendicitis is the most common cause of emergency operation in general surgery and is typically treated with antibiotics and timely appendectomy with minimal adverse outcomes (Ferris M, Quan S, Kaplan BS, et al. The global incidence of appendicitis: a systematic review of population-based studies. Ann Surg 2017;266:237-41 and Poon S, Lee J, NG KM, Chiu GWY, et al. The current management of acute uncomplicated appendicitis: should there be a change in paradigm? A systematic review of the literatures and analysis of treatment performance. WJES 2017;12:46). Unfortunately, the identification of pyelephlebitis is difficult to make due to its nonspecific clinical presentation and can result in significant morbidity or mortality if not appropriately treated. Certain laboratory derangements and positive intra-abdominal imaging combined with a high index of suspicion can make the diagnosis. Treatment involves broad-spectrum antibiotics, anticoagulation, and source control of the primary nidus of infection. Our case presentation follows the successful clinical course of a young male diagnosed with acute appendicitis complicated by pylephlebitis. He was treated with antibiotics and anticoagulation followed by interval laparoscopic appendectomy with consequential resolution of thrombus on subsequent cross-sectional imaging.

Optical forces in heat-assisted magnetic recording head-disk interface

A main challenge in Heat-Assisted Magnetic Recording technology is the build-up of contaminants called smear on the near field transducer. In this paper, we investigate the role of optical forces originating from the electric field gradient in the formation of smear. First, based on suitable theoretical approximations, we compare this force with air drag and the thermophoretic force in the head-disk interface for two smear nanoparticle shapes. Then, we evaluate the force field's sensitivity to the relevant parameter space. We find that the smear nanoparticle's refractive index, shape, and volume significantly impact the optical force. Further, our simulations reveal that the interface conditions, such as spacing and the presence of other contaminants, also influence the magnitude of the force.

Whole-Genome Resequencing of Spontaneous Oxidative Stress-Resistant Mutants Reveals an Antioxidant System of Bradyrhizobium japonicum Involved in Soybean Colonization

Soybean is the most inoculant-consuming crop in the world, carrying strains belonging to the extremely related species Bradyrhizobium japonicum and Bradyrhizobium diazoefficiens. Currently, it is well known that B. japonicum has higher efficiency of soybean colonization than B. diazoefficiens, but the molecular mechanism underlying this differential symbiotic performance remains unclear. In the present study, genome resequencing of four spontaneous oxidative stress-resistant mutants derived from the commercial strain B. japonicum E109 combined with molecular and physiological studies allowed identifying an antioxidant cluster (BjAC) containing a transcriptional regulator (glxA) that controls the expression of a catalase (catA) and a phosphohydrolase (yfbR) related to the hydrolysis of hydrogen peroxide and oxidized nucleotides, respectively. Integrated synteny and phylogenetic analyses supported the fact that BjAC emergence in the B. japonicum lineage occurred after its divergence from the B. diazoefficiens lineage. The transformation of the model bacterium B. diazoefficiens USDA110 with BjAC from E109 significantly increased its ability to colonize soybean roots, experimentally recapitulating the beneficial effects of the occurrence of BjAC in B. japonicum. In addition, the glxA mutation significantly increased the nodulation competitiveness and plant growth-promoting efficiency of E109. Finally, the potential applications of these types of non-genetically modified mutant microbes in soybean production worldwide are discussed.

Multiple ways to evade the bacteriostatic action of glyphosate in rhizobia include the mutation of the conserved serine 90 of the nitrogenase subunit NifH to alanine

The genome resequencing of spontaneous glyphosate-resistant mutants derived from the soybean inoculant E109 allowed identifying genes most likely associated with the uptake (gltL and cya) and metabolism (zigA and betA) of glyphosate, as well as with nitrogen fixation (nifH). Mutations in these genes reduce the lag phase and improve nodulation under glyphosate stress. In addition to providing glyphosate resistance, the amino acid exchange Ser90Ala in NifH increased the citrate synthase activity, growth rate and plant growth-promoting efficiency of E109 in the absence of glyphosate stress, suggesting roles for this site during both the free-living and symbiotic growth stages.

Importancia de la biopsia de hueso en el diagnóstico de las enfermedades metabólicas óseas

Objetivo. Evaluar la importancia de las biopsias óseas en el diagnóstico de las enfermedades óseas metabólicas, su relación con la densitometría ósea (DMO) y los biomarcadores. Métodos. Estudio transversal, descriptivo. Se efectuaron biopsias de la cresta pelviana a 38 personas, 36 mujeres (34 menopáusicas y 2 premenopáusicas) y 2 varones. DMO en columna vertebral, cadera y/o antebrazo por absorciometría dual de rayos X. Se determinó calcio, fósforo, osteocalcina, fosfatasa alcalina, vitamina D, parathormona, hemoglobina, transaminasas, proteínas totales y fracciones en sangre y en orina, N-telopéptido de enlaces de colágeno tipo I, calcio y fósforo por métodos convencionales. Resultados. La edad promedio de 34 mujeres postmenopáusicas fue 58 ± 7,79 y el tiempo de la menopausia 11,48 ± 8,76 años; la DMO promedio en columna, cadera y antebrazo fue de -2,88 ± 1,16, -2,13 ± 0,82, y -5,14 ± 1,76, respectivamente; la biopsia demostró osteoporosis en 33 y enfermedad de Paget en 1. Dos varones de 48 y 63 años, con DMO en antebrazo de -3,2 y -4,9, y osteoporosis en la biopsia. Mujer de 34 años con DMO -3 y osteoporosis en biopsia; y una mujer de 29 años con DMO -3 y osteomalacia en biopsia. Hubo correlación negativa entre la edad y duración de la menopausia con la disminución de la DMO. Conclusiones. Hubo correlación entre la edad y tiempo de menopausia con la disminución de la DMO. Una DMO baja no siempre es osteoporosis,puede tratarse de otra enfermedad ósea metabólica como osteomalacia o enfermedad de Paget. La biopsia ósea es el procedimiento más confiable para el diagnóstico de estas enfermedades.

Endoscopic and surgical management of Bouveret's syndrome complicated by gallstone ileus

Bouveret’s syndrome is a rare complication that occurs most commonly in elderly patients with multiple comorbidities. It is secondary to an impacted gallstone causing gastric outlet obstruction from a cholecystoduodenal fistula, and there is no defined standardized management in current literature. A 92-year-old woman presents to our tertiary community hospital with abdominal discomfort concerning for bowel obstruction. Computed tomography revealed pneumobilia with a cholecystoduodenal fistula and a large gallstone in the proximal duodenum causing gastric outlet obstruction. The impacted gallstone failed endoscopic extraction with electrohydraulic lithotripsy, and patient subsequently developed distal gallstone ileus requiring exploratory laparotomy and enterolithotomy. This case report examines the need for early coordinated endoscopic and surgical management of a patient with Bouveret’s syndrome complicated by gallstone ileus as it is associated with high morbidity and mortality rates.

Efficacy of a Novel Cholangiogram Simulator for Training Laparoscopic Intraoperative Cholangiography

OBJECTIVE

Determine the efficacy of a novel low-cost, reusable simulator for training fundamental skills associated with safe and effective intraoperative cholangiography (IOC).

DESIGN

The simulator uses a balloon and retention suture tubing (representing the gallbladder, cystic duct, common bile duct, and common hepatic duct) attached to a piece of wood and placed in a laparoscopic trainer (representing the abdominal cavity) covered by a piece of simulated skin to obscure it. Following a tutorial on performing a simulated IOC using this, simulation participants independently completed a video-recorded simulated IOC and a post-training survey about the appearance and perceived usefulness of the IOC simulator as a training tool. Two experienced surgeons assessed participants' IOC performance using an IOC procedural checklist developed for this purpose. Procedural time (in seconds) was recorded and used as an additional measure of performance.

SETTING

The OhioHealth Learning Center simulation facility in the Department of Surgery at Riverside Methodist Hospital, a large tertiary care independent medical center that is part of the OhioHealth care system.

PARTICIPANTS

Eleven attending surgeons and 16 general surgery residents of different levels participated in the simulation. Two experienced surgeons assessed participants' IOC performance. One participated in the simulation along with the other 10 surgeons; the other did not.

RESULTS

High-experience participants completed more steps and spent less time than low-experience individuals; however, differences were not statistically significant. There was substantial agreement between the 2 observers regarding participants' performance. Participants scored the simulator as realistic and useful in teaching relevant steps associated with IOC.

CONCLUSIONS

Despite differences between high- and low-experience participants in steps completed and time spent, these results did not prove statistically significant. Additional studies to increase sample size are warranted to determine if significant differences exist. However, participants did generally find the simulator to be an effective training tool.

PSV-32 Influence of chlorate and chlorate plus molybdate on the growth of multi-drug resistant staphylococci

This study was conducted to determine the effects of chlorate, a metabolic precursor of the bactericide chlorite, when administered without or with molybdate, an essential component of a co-enzyme contributing to nitrate reductase conversion of chlorate to chlorite, against methicillin-resistant staphylococci, important mastitic-pathogens of livestock. Two methicillin-resistant Staphylococcus aureus (strains CP and 49521) were individually cultured for 12 h at 39o C in nitrate-supplemented (5 mM) ½-strength Brain Heart Infusion broth (10 mL/tube) treated without (control) or with 5 mM chlorate (CL) or 5 mM chlorate plus 1 mM molybdate (CLMO). Control and treated cultures were incubated anaerobically in triplicate and growth was measured via absorbance at 600 nm. An analysis of variance revealed an inhibitory effect of treatments (P < 0.05) on maximum absorbances observed after the 12-h incubation, with maximum absorbances for CP (1.22, 0.10, and 0.46; SEM = 0.12) and 49521 (1.24, 0.22 and 0.06, SEM = 0.09) being higher in controls than in CL- and CLMO-treated cultures, respectively. Similarly, mean specific growth rates of S. aureus CP and 49521 were inhibited (P < 0.05) by both treatments during the first 6 h of growth, with rates being most rapid in control cultures, intermediate in CLMO-treated cultures and slowest in CL-treated cultures (0.68, 0.27 and 0.03 h-1, SEM= 0.15; and 0.92, 0.47 and 0.09 h-1, SEM = 0.08; for CP and 40521, respectively). Growth rates did not differ (P > 0.05) between controls or treatments during the last 6 h of incubation, averaging 0.74 and 0.75 h-1 for both CP and 49521 (SEM = 0.20 and 0.22, respectively). These results confirm that chlorate treatment inhibits methicillin-resistant Staphylococcus aureus strains CP and 49521 although moderate adaption by these strains began to occur after 6 h incubation which, contrary to expectation, was not overcome by co-treatment with molybdate.

Características del metabolismo óseo en mujeres con osteoporosis posmenopáusica de un hospital de Lima

Introducción: En nuestro medio no existen estudios que evaluen los diversos marcadores de recambio óseo en mujeres con osteoporosis posmenopáusica, considerando la alta tasa de morbimortalidad asociada a las fracturas por fragilidad. Objetivo: Conocer las características bioquímicas del metabolismo óseo en mujeres posmenopáusicas con osteoporosis. Métodos: Estudio transversal. Se incluyeron a 49 mujeresposmenopáusicas con osteoporosis, a quienes se midió la densidad mineral ósea por absorciometría dual de rayos X en columna lumbar, cadera y antebrazo. Se determinó calcio, fósforo, osteocalcina, fosfatasa alcalina, vitamina D y paratohormona en sangre y en orina, N-telopéptido de enlaces de colágeno tipo I, calcio y fósforo por métodos convencionales. Resultados: La edad promedio fue 59,1 ± 7,5 años. El tiempo medio de menopausia fue 12,0±7,9 años. Todas tuvieron osteoporosis en antebrazo, 55,1%, en columna lumbar y 18,4%, en cadera total. Valores insuficientes de vitamina D tuvo el 46,9% y 8,2, valores deficientes. La osteocalcina fue normal en 73,5%, disminuida en 20,1% y alta en 6,4%. Se encontró correlación positiva entre la edad y la concentración de paratohormona, y negativa con la vitamina D. La fosfatasa alcalina tuvo correlación positiva con la duración de la menopausia. Conclusión: La mayor extensión de osteoporosis tuvo correlación con la edad y tiempo de menopausia. Más de la mitad de mujeres tuvieron niveles bajos de vitamina D.

Electrostatically Tunable Adhesion in a High Speed Sliding Interface

Contact hysteresis between sliding interfaces is a widely observed phenomenon from macro- to nanoscale sliding interfaces. Most such studies are done using an atomic force microscope (AFM) where the sliding speed is a few μm/s. Here, we present a unique study on stiction between the head-disk interface of commercially available hard disk drives, wherein the vertical clearance between the head and the disk is of the same order as in various AFM-based fundamental studies but with a sliding speed that is nearly 6 orders of magnitude higher. We demonstrate that, although the electrostatic force (dc or ac voltage) is an attractive force, the ac-voltage-induced out-of-plane oscillation of the head with respect to the disk is able to completely suppress the contact hysteresis.

Effect of Supplemental Corn Dried Distillers Grains with Solubles Fed to Beef Steers Grazing Native Rangeland during the Forage Dormant Season

Two experiments were conducted to evaluate the effects of the level of corn dry distillers grains with solubles (CDDGS) supplementation on growing performance, blood metabolites, digestion characteristics and ruminal fermentation patterns in steers grazing dormant forage. In Exp. 1, of growth performance, 120 steers (204±5 kg initial body weight [BW]) were distributed randomly into 3 groups (each of 40 steers), which were provided with the following levels of CDDGS supplement: 0%, 0.25%, or 0.50% BW. All groups of steers were grazed for 30 days in each of 3 grazing periods (March, April, and May). Approximately 1,000 ha of the land was divided with electric fencing into 3 equally sized pastures (333 ha in size). Blood samples were collected monthly from 20 steers in each grazing group for analysis of glucose (G), urea-nitrogen (UN) and non-esterified fatty acids. Final BW, average daily gain (ADG) and supplement conversion (CDDGS-C) increased with increasing levels of CDDGS supplementation (p<0.05).The CDDGS supplementation also increased the plasma G and UN concentrations (p<0.05). In Exp. 2, of digestive metabolism, 9 ruminally cannulated steers (BW = 350±3 kg) were distributed, following a completely randomized design, into groups of three in each pasture. The ruminally cannulated steers were provided the same levels of CDDGS supplementation as in the growing performance study (0%, 0.25%, and 0.50% BW), and they grazed along with the other 40 steers throughout the grazing periods. The dry matter intake, crude protein intake, neutral detergent fiber intake (NDFI), apparent digestibility of dry matter (ADDM), crude protein (ADCP) and neutral detergent fiber (ADNDF) increased with increasing levels of CDDGS supplementation (p<0.05). The ruminal degradation rates of CP (kdCP), NDF (kdNDF) and passage rate (kp) also increased with increasing levels of CDDGS supplementation (p<0.05). Ruminal ammonia nitrogen (NH₃-N) and propionate concentrations also increased with increasing levels of CDDGS supplementation (p<0.05). However, acetate concentrations decreased with increasing levels of CDDGS supplementation (p<0.05). Liquid dilution rate increased with increasing levels of CDDGS supplementation but ruminal liquid volume decreased (p<0.05). On the basis of these findings, we can conclude that CDDGS supplementation enhanced the productive performance of cattle grazing native rangeland without negatively affecting forage intake, glucose and urea-nitrogen blood concentrations, ruminal degradation and ruminal fermentation patterns.

Effects of Candida norvegensis Live Cells on In vitro Oat Straw Rumen Fermentation

This study evaluated the effect of Candida norvegensis (C. norvegensis) viable yeast culture on in vitro ruminal fermentation of oat straw. Ruminal fluid was mixed with buffer solution (1:2) and anaerobically incubated with or without yeast at 39°C for 0, 4, 8, 16, and 24 h. A fully randomized design was used. There was a decrease in lactic acid (quadratic, p = 0.01), pH, (quadratic, p = 0.02), and yeasts counts (linear, p<0.01) across fermentation times. However, in vitro dry matter disappearance (IVDMD) and ammonia-N increased across fermentation times (quadratic; p<0.01 and p<0.02, respectively). Addition of yeast cells caused a decrease in pH values compared over all fermentation times (p<0.01), and lactic acid decreased at 12 h (p = 0.05). Meanwhile, yeast counts increased (p = 0.01) at 12 h. C. norvegensis increased ammonia-N at 4, 8, 12, and 24 h (p<0.01), and IVDMD of oat straw increased at 8, 12, and 24 h (p<0.01) of fermentation. Yeast cells increased acetate (p<0.01), propionate (p<0.03), and butyrate (p<0.03) at 8 h, while valeriate and isovaleriate increased at 8, 12, and 24 h (p<0.01). The yeast did not affect cellulolytic bacteria (p = 0.05), but cellulolytic fungi increased at 4 and 8 h (p<0.01), whereas production of methane decreased (p<0.01) at 8 h. It is concluded that addition of C. norvegensis to in vitro oat straw fermentation increased ruminal fermentation parameters as well as microbial growth with reduction of methane production. Additionally, yeast inoculum also improved IVDMD.

Epidemiological profile of colombian patients with rheumatoid arthritis in a specialized care clinic

INTRODUCTION

Few studies report the epidemiological profile of RA patients attending clinics for comprehensive care. We describe the clinical, socio-demographic characteristics and comorbidities of a cohort of patients with RA.

METHODS

Cross-sectional study in a cohort of patients according to ACR criteria/EULAR 2010 classification who have entered to the AR clinic since October 2012 until May 2014, referred from primary care. Frequencies for socio-demographic, comorbidity, state of disease activity, functional status, biomarkers and therapeutic modalities variables are described.

RESULTS

In total, 1652 patients were included with a mean age of 58 years and a duration of 9 years. Rheumatoid factor was positive in 80% and anti-citrullinated peptide antibody in 63% of patients. In total, 43.6% of patients had comorbidities: Hypertension (20.4%), osteoporosis (17.3%) and Sjögren's syndrome (10.4%). Fifty percent of the patients had moderate and high disease activity level measured by DAS-28 score, and the mean HAQ score was 0.64 (DS 1.12). Seventy three percent of patients were treated with oral disease modified anti rheumatic treatment and 63.6% of them were with methotrexate. 42.4% of the patients were treated with glucocorticoids (mean dose 6.3mg).

CONCLUSIONS

The epidemiological behavior of a group of RA patients is reported. The presence of comorbidities is significant affecting the risk of morbidity and mortality in these patients. The definition of the epidemiological profile of this population will allow the design of research questions to resolve outstanding problems in the clinical context of this pathology.

Perforated Crohn's disease presenting during pregnancy

Severe exacerbations of Crohn's disease (CD) requiring acute surgery are rare, and rarer still are those that occur during pregnancy. We present a case of perforated CD in an obstetric patient. A 24-year-old woman at 27 weeks gestation, with abdominal pain, leucocytosis and concern for preterm labour, presented to our institution. MRI was obtained and demonstrated a phlegmon in the small bowel mesentery near the distal ileum, with concern for perforation. The patient was taken for an emergent exploratory laparotomy. Intraoperatively, an ileal perforation with small bowel fistula was observed and an ileocolectomy with primary anastomosis was performed. Pathology of the resection revealed CD, a new diagnosis for the patient. She was ultimately discharged on postoperative day 13 and later went on to deliver a healthy term infant, and, 5 years later, has had no significant recurrence.

Effect of repeated suboptimal chlorate treatment on ruminal and fecal bacterial diversity

The minimal effective dose of sodium chlorate as an intervention to reduce the carriage of pathogenic bacteria in food-producing animals has not been clearly established. The effect of low-level oral chlorate administration to ewes was assessed by comparing the diversity of prominent bacterial populations in their gastrointestinal tract. Twelve lactating crossed Pelibuey and Blackbelly-Dorper ewes (average body weight, 65 kg) were randomly assigned (four per treatment) to receive a control treatment (TC; consisting of 3 g of NaCl per animal per day) or one of two chlorate treatments (T3 or T9; consisting of 1.8 or 5.4 g of NaClO3 per animal per day, respectively). Treatments were administered twice daily via oral gavage for 5 days. Ruminal and fecal samples were collected daily, starting 3 days before and ending 6 days after treatment, and were subjected to denaturing gradient gel electrophoresis of the 16S rRNA gene sequence amplified from total population DNA. For ruminal microbes, percent similarity coefficients (SCs) between groups varied from 23.0 to 67.5% and from 39.4 to 43.3% during pretreatment and treatment periods, respectively. During the treatment period, SCs within groups ranged from 39.4 to 90.3%, 43.3 to 86.7%, and 67.5 to 92.4% for TC, T3, and T9, respectively. For fecal microbes, SCs between groups varied from 38.0 to 85.2% and 38.0 to 94.2% during pretreatment and treatment periods, respectively. SCs for fecal populations during treatment were most varied for TC (38.0 to 67.9%), intermediate for T9 (75.6 to 92.0%), and least varied for T3 (80.6 to 90.6%). Heterogeneity within and between groups provided no evidence of an effect of chlorate treatment on ruminal or fecal microbial populations.

Inmunofenotipo de leucemias agudas del Hospital Nacional Dos de Mayo, durante el periodo 2011-julio 2012

Objetivos: Determinar la prevalencia de leucemias agudas, por inmunofenotipo. Diseño: Descriptivo transversal. Institución: Instituto de Investigaciones Clínicas, Facultad de Medicina, UNMSM, y Hospital Nacional Dos de Mayo (HNDM). Participantes: Pacientes con neoplasias hematológicas atendidos en el HNDM en el periodo 2011-julio 2012. Intervenciones: A todos los pacientes se realizó hemograma, mielograma, citometría de flujo (sangre medular). Principales medidas de resultados: Prevalencia de neoplasias hematológicas y leucemias agudas, características inmunofenotípicas. Resultados: Se encontró 80 neoplasias hematológicas: 42 (52,5%) leucemias agudas, 21(26,3%) mieloma múltiple, 8 (10%), linfomas, 5 (6,3%) síndromes mieloproliferativos crónicos, 4 (5%) mielodisplasias. Las leucemias agudas con citometría, en 12 (41,4%) mujeres y 17 (58,6%) varones se encontró lla 17 (40,5%), 12 (28,6%) lma, 13 (30,9%) no tipificada. Características inmunofenotipicas de las lla: 2 fueron t y 15 b. Orden de frecuencia: lla común pura (10), lla pre b (02), lla pro b (02) lla bifenotípica (01). En lma: (12) lma–m2 (08), lma-m0 (1), lma-m1 (1), lma–m3 (1), lma-m5 (1). Conclusiones: 52% de las neoplasias en el HNDM fueron leucemias agudas. La lla b común fue la más frecuente (58,8% respecto a lla y 34,5% a todas las leucemias agudas con citometría), prevalencia similar a otros estudios internacionales.

Alteraciones dermatológicas en pacientes con anemias carenciales

Objetivos: Determinar la frecuencia de las alteraciones dermatológicas relacionadas a las anemias carenciales, así como el tipo y grado de severidad de la anemia. Materiales y Métodos: Se estudió 100 pacientes mayores de 18 años con anemia carencial atendidos en el Hospital Dos de Mayo, entre enero y noviembre de 2004. A todos se les realizó hemograma, constantes corpusculares y determinación sérica de hierro, ferritina, ácido fólico y vitamina B12. Resultados: En orden de frecuencia, el tipo de anemia fue ferropénica 45%, carencial mixta (ferropénica y megaloblástica) 35% y megaloblástica 20%. Las manifestaciones dermatológicas más frecuentes fueron palidez 100%, glositis atrófica 81%, queilitis angular 60%, coiloniquia 33%, escleras azuladas 30%, fragilidad capilar 29%, fragiliadad ungueal 29%. El grado de anemia más frecuente fue el severo, 75%. Conclusiones: El 80% de pacientes presentó más de cuatro alteraciones dermatológicas: palidez, glositis atrófica, queilitis angular, coiloniquia y escleras azuladas. La anemia carencial más frecuente fue la ferropénica, con 45%.

Chemical Composition, In vitro Gas Production, Ruminal Fermentation and Degradation Patterns of Diets by Grazing Steers in Native Range of North Mexico

The objective of the study was to quantify annual and seasonal differences in the chemical composition, in vitro gas production, in situ degradability and ruminal fermentation of grazing steers’ diets. Diet samples were collected with four esophageal cannulated steers (350±3 kg BW); and four ruminally cannulated heifers (342±1.5 kg BW) were used to study the dry matter degradation and fermentation in rumen. Data were analyzed with repeated measurements split plot design. The crude protein, in vitro dry matter digestibility and metabolizable energy were higher during the first year of trial and in the summer (p<0.01). The values of calcium, phosphorus, magnesium, zinc and copper were higher in summer (p<0.05). The gas produced by the soluble and insoluble fractions, as well as the constant rate of gas production were greater in summer and fall (p<0.01). The ammonia nitrogen (NH₃N) and total volatile fatty acids concentrations in rumen, the soluble and degradable fractions, the constant rate of degradation and the effective degradability of DM and NDF were affected by year (p<0.05) and season (p<0.01). Our study provides new and useful knowledge for the formulation of protein, energetic and mineral supplements that grazing cattle need to improve their productive and reproductive performance.

[Long-term visual acuity in patients with age-related macular degeneration and persistence of subretinal fluid after treatment with ranibizumab]

OBJECTIVE

To analyse the long-term visual acuity (VA) in patients with age-related macular degeneration (ARMD) treated with ranibizumab, and who had persistent subretinal fluid after the induction therapy and/or in the successive controls.

MATERIALS AND METHODS

We reviewed the medical records, optical coherence tomography (OCT) and fluorescein angiograms of 216 patients treated with ranibizumab between January 2008 and April 2010, selecting those who had persistent subretinal fluid or recurrent fluid for at least one year of follow-up.

RESULTS

A total of 36 eyes from 34 patients were included, with 19 eyes (52.7%) having persistent, and 17 (47.2%) recurrent subretinal fluid throughout the follow- up (mean 29.06±9.28 months). The average number of injections was 7.89±3.2. The central macular thickness (CMT) at the start of follow-up was 330±84μm, at 3 months 265.2±62μm, and 294.5±37μm at the end of the follow-up. The initial mean VA was 0.3±0.2, at 3 months 0.43±0.2 (P<.05) and at the final review, 0.41±0.22 (P<.05). Haemorrhages in recurrences were associated with a worse final VA (P=.004). At the end of follow-up, 18 eyes (50%) continued with ranibizumab treatment, 16 eyes (44%) were kept under observation, and 2 patients died. There were no differences between VA and CMT between the groups.

CONCLUSIONS

The persistence or recurrence of macular subretinal fluid in patients treated with ranibizumab does not significantly reduce the visual gain obtained after induction therapy, despite discontinuation of treatment during follow-up. Haemorrhages in the recurrences were associated with a worse final VA.

Volume Visual Attention Maps (VVAM) in ray-casting rendering

This paper presents an extension visual attention maps for volume data visualization, where eye fixation points become rays in the 3D space, and the visual attention map becomes a volume. This Volume Visual Attention Map (VVAM) is used to interactively enhance a ray-casting based direct volume rendering (DVR) visualization. The practical application of this idea into the biomedical image visualization field is explored for interactive visualization.

Growth of Hydrogenated Amorphous Silicon (A-Si:H) on Patterned Substrates for Increased Mechanical Stability

Residual stress in hydrogenated amorphous silicon (a-Si:H) film has been studied. Deposition on square island pattern reduced the stress when the lateral dimension of the islands became comparable to the film thickness. The overall stress was reduced by approximately 40% when the lateral dimension was decreased to 40 μm, but the adhesion was not improved much. However, substrates having a 2-dimensional array of inversed pyramids of 200 μm in lateral dimension produced overall stress 3∼4 times lower than that on the normal substrates. The inversed pyramid structure also had other advantages including minimized delamination and increased effective thickness. Computer simulation confirmed that the overall stress can be reduced by deposition on the pyramidal structure.

Impact of the 80-hour workweek on surgical case exposure within a general surgery residency program

OBJECTIVE

The objective of this statistical analysis was to test the hypothesis that implementation of the 80-hour workweek restrictions for General Surgery residents at Riverside Methodist Hospital after July 2003 decreased their operative experience relative to surgical residents trained at Riverside before these changes.

DESIGN, SETTING, PARTICIPANTS

Data were collected from the Accreditation Council for Graduate Medical Education national database and from Riverside Methodist Hospital's General Surgery Residency records for a sampling of academic years before and after the duty-hour changes in surgical education (July 1, 2003). Current procedural terminology (CPT) surgical procedure codes logged by postgraduate year (PGY) 5 General Surgery residents 15 years before and 5 years after implementation of the 80-hour workweek were compared. The outcome variables "total major cases" and "Chief cases" were compared between 2 study groups defined by the time intervals exclusively before July 2003 ("pre") and inclusively after July 2003 ("post"). Hospital general surgical case volume for the study intervals was also tallied. Statistical analyses included 1- and 2-sided t-tests, nonparametric tests, and t-tests on a 3-parameter logarithmic transformation of the data.

RESULTS

Despite an upward trend in total general surgery cases (slope = 25/year, p = 0.005), there was a statistically significant decrease in the operative experience for categorical surgical residents following the 80-hour workweek restrictions. The mean (SD) number of major cases performed by "pre"-restriction residents during their training significantly exceeded that of their "post" cohorts (1395 [326] vs 953 [134], p < 0.001). The training for PGY 5 residents was similarly influenced (345 [81] vs 237 [55], p < .0001).

CONCLUSIONS

Despite an increase in the total number of major operative cases available, the volume of cases performed by residents has decreased after implementation of the Accreditation Council for Graduate Medical Education (ACGME) work-hour restrictions. Our data suggest that the impact of the 80-hour workweek has had a detrimental effect on the conventional resident training experience.

[Ranibizumab as treatment for myopic choroidal neovascularization]

OBJECTIVE

To evaluate the efficacy of intravitreal Ranibizumab as treatment for choroidal neovascularisation due to pathological myopia.

MATERIALS AND METHODS

A retrospective, non-comparative study of 18 eyes treated with intravitreal injections of Ranibizumab. Ten eyes had been treated previously with photodynamic therapy and eight received Ranibizumab as first therapy. After thorough ophthalmologic examination, fluorescein angiography (FAG) and optical coherence tomography (OCT), intraocular injection of Ranibizumab was performed. In subsequent monthly follow ups and taking into account visual acuity, presence or absence of metamorphopsia, biomicroscopy and OCT examination, further treatment was decided.

RESULTS

Eighteen eyes from 16 patients were finally included. Patients were followed up for a minimum of 6 months. The mean age at initial treatment was 56.4 years. Mean refractive error was -13.3 diopters. Regarding FAG, all neovascular membranes were classical and sub or juxtafoveal localised. At the end of the sixth month after treatment fourteen eyes (77.7%) showed better visual acuity ranging from one or more lines on the Snellen chart, eleven eyes (61.1%) improved two lines or more, three eyes (16.6%) did not show any change and one eye (5.5%) worsened by one line. At 6 months the mean best-corrected visual acuity improved from 0.25 to 0.46 (p= 0.001). The mean central macular thickness decreased from 344.9 to 212.6 (p=0.015).

CONCLUSIONS

Ranibizumab may be a good therapeutic option as treatment for choroidal neovascularisation due to pathological myopia; it improved visual acuity and anatomical features, even in non-responders to photodynamic therapy (Arch Soc Esp Oftalmol 2009; 84: 507-514).

Desenlaces clínicos en artritis reumatoidea tratada con infliximab: Hospital de San José, 2007-2008

Objetivo: describir los resultados clínicos obtenidos en los pacientes con artritis reumatoidea que recibieron infliximab durante el período enero de 2007 a octubre de 2008. Pacientes y métodos: se revisaron 240 historias clínicas de enfermos con AR atendidos en el lapso correspondiente, de las cuales 73 tenían información disponible que cumpliera los criterios de inclusión y exclusión. Se analizaron las características clínicas y sociodemográficas, el comportamiento de la respuesta terapéutica si la hubo y el tiempo de aparición, el uso de medicamentos coadyuvantes y el desarrollo de eventos adversos. Resultados: se describieron 73 pacientes, de los cuales el 89,04% fueron mujeres con edad promedio de 49.7 años y evolución de la AR de 12.0 (± 8.8) años, quienes recibieron 3 mg/k de infliximab con un número promedio de dosis de 9.1. Se obtuvo respuesta terapéutica en 52,05% a las 24.15 (±19.5) semanas de tratamiento. En contraste, los pacientes restantes que aun no tenían mejoría y continuaban con el tratamiento, llevaban con el medicamento un promedio de 26.65 (±22.5) semanas. La terapia fue suspendida en 29 pacientes: 11 (15,06%) de manera temporal y 18 (24,65%) permanente. Conclusiones: el infliximab redujo la actividad inflamatoria en más de la mitad de los enfermos del presente estudio con una baja frecuencia de efectos adversos. Dicha respuesta se documentó con el control en las articulaciones dolorosas e inflamadas. No hubo relación positiva con los marcadores inflamatorios, aclarando el bajo reporte de los mismos en las historias clínicas revisadas. Abreviaturas: AR, artritis reumatoidea; FNT-a, factor de necrosis tumoral; CAR, Colegio Americano de Reumatología.

[Photodynamic therapy in retinal pigment epithelium detachment associated with long term central serous chorioretinopathy]

PURPOSE

To present a case of long term central serous corioretinopathy associated with chronic detachment of the retinal pigment epithelium (RPE) and the effect of photodynamic therapy on it.

CASE CLINIC

We present the case of a 46-year old man with long term chronic central serous chorioretinopathy (18 mo.) with chronic detachment of RPE in his left eye who underwent PDT with Verteporfin (Visudyne). BCVA improved from 0.7 to 1 and metamorphopsia disappeared within one month of treatment. The patient remained asymptomatic for a follow-up period of 15 months.

DISCUSSION

Choroidal hyperpermeability is found in central serous chorioretinopathy as a primary involvement factor. PDT with Verteporfin induces a transient reduction in choriocapilaris blood flow and can be used as treatment in cases of chronic central serous chorioretinopathy.

Parathyroid hormone and bone marker levels in patients with morbid obesity before and after biliopancreatic diversion

BACKGROUND

Scopinaro biliopancreatic diversion (BPD) is associated with malabsorption of calcium and vitamin D, which manifests as a secondary hyperparathyroidism (SHP) and may lead to osteopenia.

METHODS

96 morbidly obese patients were studied (age 19-60 years, 23 men and 73 women, with mean initial BMI 53) following intervention by Scopinaro BPD. The change in iPTH levels, urine DPD, Pyrilinks-D of DPC and serum CTx were studied at 0, 3, 6, 12, 18 and 24 months after surgery. Postoperatively, they were given supplements of calcium and vitamin D3. The control group consisted of 67 non-obese women and 10 men.

RESULTS

The iPTH levels gradually increased after BPD, with a substantial difference compared to presurgery levels at month 6. In spite of the calcium and vitamin D supplements, 77% of the patients with presurgery SHP did maintain high levels of iPTH after 2 years. The percentage of SHP among the patients with normal pre-surgery iPTH was 58%. The basal figures of DPD/cre were significantly higher than in the control group, 9.06 (4.6-13.5) nM/mMcre vs 3.9 (2.8-5.6) in men and 6.75 (5.4-7.9) vs 7.67 (3.3-11.6) in women, but not CTx, 0.24 (0.02-0.89) vs 0.22 (0.07-0.55). After the operation, there was a noticeable increase which persisted at 2 years. There was a lack of correlation between the levels of iPTH and the bone resorption markers, i.e. the first ones decreased from month 6 in men and from month 12 in women, while the levels of iPTH continued to increase.

CONCLUSION

In obese patients, we found no correlation between iPTH levels and BMI. Supplements of calcium and vitamin D did not prevent the appearance of SHP following BPD. The patients with high pre-surgery iPTH levels have a higher risk of malabsorption of calcium and vitamin D. Following malabsorptive bariatric surgery, there is an increase in bone resorption, which results in DPD and CTx increase. Those markers do not correlate with iPTH, and this may suggest that there is a phenomenon of bone reshaping parallel to the loss of weight.

Recycling of an electric arc furnace flue dust to obtain high grade ZnO

The production of steel in electric arc furnace (EAF) generates a by-product called EAF dusts. These steelmaking flue dusts are classified in most industrialized countries as hazardous residues because the heavy metals contained in them, tend to leach under slightly acidic rainfall conditions. However, and at the same time they contain zinc species which can be used as a source to obtain valuable by-products. The present investigation shows results on the processing of an EAF flue dust using ammonium carbonate solutions. Once zinc is dissolved: ZnO + 4NH3 + H2O --> Zn(NH3)4(2+) + 2OH- with other impurities (i.e. cadmium and copper), these are eliminated from the zinc solution via cementation with metallic zinc. The purified zinc solution was evaporated (distilled) until precipitation of a zinc carbonate species, which then was calcined to yield a zinc oxide of a high grade. For the unattacked dust residue from the leaching operation, mainly composed of zinc ferrite, several options can be considered: back-recycling to the furnace, further treatment by sodium hydroxide processing or a more safely dumping due to its relatively inertness.

A novel detection strategy for odorant molecules based on controlled bioengineering of rat olfactory receptor I7

In this study, we report a dose-dependent detection of odorant molecules in solution by rat olfactory receptor I7 (OR I7) in its membrane fraction. The OR I7 is immobilized on a gold electrode by multilayer bioengineering based on a mixed self-assembled monolayer and biotin/avidin system, which allows for a well-controlled immobilization of the bioreceptor within its lipid environment. The odorant detection is electronically performed in a quantitative manner by electrochemical impedance spectroscopy (EIS) measurements on samples and controls.

A Prospective Study of Bile Leaks after Laparoscopic Cholecystectomy for Acute Cholecystitis

Surgeons are increasingly performing laparoscopic cholecystectomy in the setting of acute cholecystitis. The acutely inflamed gallbladder poses a more technically demanding dissection with potential for an increase in bile leak rates. Clinical and subclinical bile leak rates after laparoscopic and open cholecystectomy in the elective setting are known. This study prospectively evaluates the rate of clinical and subclinical bile leaks after laparoscopic cholecystectomy in the setting of acute cholecystitis. One hundred patients underwent laparoscopic cholecystectomy for acute cholecystitis, as determined intraoperatively and by history, ultrasound, fever, or leukocytosis. On postoperative Day 1, the patients underwent cholescintigraphy (PIPIDA scan) analyzed by a board-certified radiologist for evidence of bile leaks. Postoperative cholescintigraphy revealed eight scans positive for bile leaks. Regardless of scan result, no patient experienced a clinically symptomatic bile leak. Laparoscopic cholecystectomy is a safe and effective treatment for acute cholecystitis with acceptable clinical and subclinical bile leak rates.

A prospective study of bile leaks after laparoscopic cholecystectomy for acute cholecystitis

Surgeons are increasingly performing laparoscopic cholecystectomy in the setting of acute cholecystitis. The acutely inflamed gallbladder poses a more technically demanding dissection with potential for an increase in bile leak rates. Clinical and subclinical bile leak rates after laparoscopic and open cholecystectomy in the elective setting are known. This study prospectively evaluates the rate of clinical and subclinical bile leaks after laparoscopic cholecystectomy in the setting of acute cholecystitis. One hundred patients underwent laparoscopic cholecystectomy for acute cholecystitis, as determined intraoperatively and by history, ultrasound, fever, or leukocytosis. On postoperative Day 1, the patients underwent cholescintigraphy (PIPIDA scan) analyzed by a board-certified radiologist for evidence of bile leaks. Postoperative cholescintigraphy revealed eight scans positive for bile leaks. Regardless of scan result, no patient experienced a clinically symptomatic bile leak. Laparoscopic cholecystectomy is a safe and effective treatment for acute cholecystitis with acceptable clinical and subclinical bile leak rates.

Immobilization of native membrane-bound rhodopsin on biosensor surfaces

In this paper, we evaluated the grafting of G-protein-coupled receptors (GPCRs) onto functionalized surfaces, which is a primary requirement to elaborate receptor-based biosensors, or to develop novel GPCR assays. Bovine rhodopsin, a prototypical GPCR, was used in the form of receptor-enriched membrane fraction. Quantitative immobilization of the membrane-bound rhodopsin either non-specifically on a carboxylated dextran surface grafted with long alkyl groups, or specifically on a surface coated with anti-rhodopsin antibody was demonstrated by surface plasmon resonance. In addition, a new substrate based on mixed self-assembled multilayer that anchors specific anti-receptor antibodies was developed. Electrochemical impedance spectroscopy performed upon deposition of membrane-bound rhodopsin of increasing concentration exhibited a significant change, until a saturation level was reached, indicating optimum receptor immobilization on the substrate. The structures obtained with this new immobilization procedure of the rhodopsin in its native membrane environment are stable, with a controlled density of specific anchoring sites. Therefore, such receptor immobilization method is attractive for a range of applications, especially in the field of GPCR biosensors.

[A case of punctate inner choroidopathy: differential diagnosis]

CASE REPORT

We present the case of a 27-year old woman suffering from a chorioretinal inflammatory disease that was diagnosed as punctate inner choroidopathy (PIC) after a complete ophthalmic evaluation.

DISCUSSION

PIC must be taken into consideration when evaluating a patient with a white dot syndrome.

[Central serous choroidopathy. Long term study]

PURPOSE

To investigate the demographic characteristics, clinical findings and long-term outcome of central serous chorioretinopathy (CSC).

METHODS

This study examined retrospectively the clinical stories and fluorescein angiographies of 113 patients with CSC and a minimum follow-up of 12 months.

RESULTS

A total of 113 patients was examined; 90 were men and 23 women. Bilateral involvement was found in 13 cases. In 85.7% of the eyes (Group I) resolution was completed in months and mean final visual acuity (VA) was 79.3/100, while 14.3% of the eyes (Group II) showed a chronic evolution, with diffuse retinal pigment epithelipathy and mean final VA of 47.2/100. The mean age of the patients in Group II was significantly higher; male:female ratio was also higher in this Group. Bilateral involvement occurred in 6% of patients from Group I and in 46.6% in Group II.

CONCLUSIONS

Chronic CSC affected less than 15% of the patients. Mean age in this group of patients was higher than in patients with a classic CSC, most of the cases were men, bilateral involvement was present in nearly 50% of the cases and 50% of them suffered a significant visual permanent impairment.

[Nd-YAG capsulotomy and intravitreal antibiotics as treatment of chronic endophthalmitis]

PURPOSE

To study the effectiveness of Yag capsulotomy, therapeutic vitreal aspiration and intravitreal injection of antibiotics combination on the treatment of chronic postoperative endophthalmitis.

METHODS

Six patients with symptoms of refractory postoperative endophthalmitis after extracapsular cataract extraction, with an intraocular lens were treated following a protocol that included: YAG capsulotomy, vitreal aspiration and intravitreal injection of antibiotics.

RESULTS

In four cases -66%- the micro-organism was isolated -three cases of coagulase- negative staphylococci and one case Corynebacterium spp. In all the cases the inflammatory process decreased, and a noticeable improvement of visual acuity was achieved. No recurrent cases were observed (two patients died before the end of the study).

CONCLUSIONS

As way of conclusion we can state that the initial capsulotomy allows the destruction of the infection reservoir in order to eradicate the agent. This endophthalmitis therapeutic alternative is effective, easy and reliable for the ophthalmologist.

Expiratory flow limitation during exercise in competition cyclists

In some trained athletes, maximal exercise ventilation is believed to be constrained by expiratory flow limitation (FL). Using the negative expiratory pressure method, we assessed whether FL was reached during a progressive maximal exercise test in 10 male competition cyclists. The cyclists reached an average maximal O2 consumption of 72 ml. kg-1. min-1 (range: 67-82 ml. kg-1. min-1) and ventilation of 147 l/min (range: 122-180 l/min) (88% of preexercise maximal voluntary ventilation in 15 s). In nine subjects, FL was absent at all levels of exercise (i.e., expiratory flow increased with negative expiratory pressure over the entire tidal volume range). One subject, the oldest in the group, exhibited FL during peak exercise. The group end-expiratory lung volume (EELV) decreased during light-to-moderate exercise by 13% (range: 5-33%) of forced vital capacity but increased as maximal exercise was approached. EELV at peak exercise and at rest were not significantly different. The end-inspiratory lung volume increased progressively throughout the exercise test. The conclusions reached are as follows: 1) most well-trained young cyclists do not reach FL even during maximal exercise, and, hence, mechanical ventilatory constraint does not limit their aerobic exercise capacity, and 2) in absence of FL, EELV decreases initially but increases during heavy exercise.

pH-dependent fluorescence of a heterologously expressed Aequorea green fluorescent protein mutant: in situ spectral characteristics and applicability to intracellular pH estimation

The green fluorescent protein of Aequorea victoria (GFP) is a natural peptide chromophore without substrate or cofactor requirements for fluorescence. In vitro, a recombinant F64L/S65T GFP mutant (GFPmut1) exhibited pH sensitive fluorescence within the physiologic range. When heterologously expressed in BS-C-1 cells or rabbit proximal tubule cells, uniform cytosolic and nuclear fluorescence was observed. Cytosolic fluorescence constituted over 80% of the total. Excitation scanning of transfected cells revealed two GFPmut1-specific regions that were pH-sensitive over the physiologic range, and each region exhibited a unique pH "bias" in fluorescence emission. Excitation at or near the expected maximum of 488 nm (region II) uniformly resulted in fluorescence that was preferentially altered at acidic pH. In contrast, a novel "wild-type" excitation peak at 400 nm (region I) resulted in alkaline-biased fluorescence similar to that described for the wild-type chromophore in vitro, suggesting that wild-type spectral features disrupted in vitro by mutagenesis may be recovered in intact cells. Calibration of intracellular pH (pHi) with in situ fluorescence following excitation in either region revealed a semilogarithmic relationship between fluorescence intensity and pH within the physiologic range. We therefore measured pHi changes attributable to altered Na/HCO3 cotransport (NBC) activity both in GFPmut1-expressing cells and in paired untransfected cells loaded with BCECF. Basal NBC activity was the same in each group, as was the stimulation of activity by 10% CO2, thus validating the utility of GFPmut1 as a fluorescent probe for pHi and establishing a novel, useful, and practical application for GFPmut1 in monitoring pHi in real time.

Postharvest analysis of vitamin C and inorganic cations in lettuce by CZE

In the present work, we used capillary zone electrophoresis (CZE) for the analysis of Vitamin C and inorganic cations (potassium, sodium, calcium, and magnesium) in lettuce (Lactuca sativa) during postharvest storage. The leaves of the creasphead lettuce samples were treated with 18 M omega water for cation analysis and, alternatively, with 3% wt/vol oxalic acid solution for ascorbic acid extraction. They were then homogenized and centrifuged, and the supernatants were introduced into the capillary for CE analysis. The cation analysis was performed on an uncoated fused-silica capillary column of 75 microns i.d. and 50 cm total length, using 15 mM creatinine, 15 mM alpha-hydroxyisobutyric acid, acetic acid, pH 4.00, as running buffer at an applied voltage of 20 kV. Indirect on-line UV detection was carried out at 214 nm. The content of Vitamin C was measured using an uncoated fused-silica capillary column of 50 microns i.d. and 45 cm total length; 10 mM sodium tetraborate, 10 mM sodium biphosphate, pH 9.00, as background electrolyte at an applied voltage of 20 kV. On-line UV detection was achieved at 254 nm.

Monitoring of homocysteine and related compounds in blood by MEKC

A reproducible, rapid procedure for the determination of homocysteine, cysteine, and glutathione in human blood by micellar electrokinetic chromatography (MEKC) has been developed. Whole blood samples were deproteinized and centrifuged, and the supernatant was directly introduced into the capillary for analysis without further derivatization. Separations were performed using an uncoated capillary of 30 cm effective length and 50 microns i.d.; 20 mM phosphate, 20 mM borate, and 50 mM SDS, pH 9.00, as running buffer; and an applied voltage of 18 kV. On-line detection was carried out at 214 nm.

[Characterization of plasmids which mediate resistance to multiple antibiotics in gram-negative bacteria of nosocomial origin]

BACKGROUND

The genetic and molecular mechanisms involved in antimicrobial resistance of 10 strains of gramnegative bacilli (1 Serratia marcescens; 2 Escherichia coli; 1 Proteus mirabilis; 4 Klebsiella pneumoniae; 1 Enterobacter cloacae y 1 Alcaligenes faecalis), isolated from adult patients with nosocomial pulmonary infection at the in-patient facilities of the University Hospital of Los Andes, Mérida, Venezuela, have been studied.

METHODS

The antimicrobial susceptibility was determined by minimum inhibitory concentrations using the dilution method in agar. The study of extrachromosomal genes was carried out by conjugation, bacterial infection with the bacteriophage M13 and curing of plasmid by acridine orange. The plasmids were isolated by alkaline lysis and analysis of restriction endonuclease digestion was carried out separately using the enzymes EcoRI and HindIII. A DNA probe, derived from the region which encodes the TEM-1 beta-lactamase of the plasmid pBR322 was used for dot-blot hybridization tests.

RESULTS

All of the gramnegative bacilli showed resistance to ampicillin, carbenicillin and cephalothin (> 128 micrograms/ml) and 3 strains also showed resistance to gentamicin (> 64 micrograms/ml). Genetic and molecular procedures showed the presence of conjugative plasmids of approximately 54 kb in all the 10 strains. The restriction patterns obtained by using EcoRI and HindIII indicated common DNA fragments in most of the plasmids studied. The dot-blot hybridization tests confirmed homology between the plasmids and the DNA probe used (TEM-1 beta-lactamase).

CONCLUSIONS

In this study, the gramnegative bacteria of nosocomial origin harbored self-transferable plasmids of approximately 54 kb, which mediate resistance to gentamicin and encode a beta-lactamase of the TEM group.

Semiconductor diode laser transscleral cyclophotocoagulation versus filtering surgery with Mitomycin-C

Both filtering surgery with Mitomycin-C and diode laser cyclophotocoagulation have proved to be effective alternatives in cases of glaucoma with poor surgical prognosis. The right eyes of 40 pigmented rabbits were randomly divided into 2 groups: Mitomycin-C group underwent filtering surgery with application of 0.4 mg/ml of Mitomycin-C whereas the diode laser (DL) group received 15 applications of 1.8 J (1800 mW. 1000 ms) distributed in 270 degrees. Mean IOP showed statistical differences in two periods between days 3-13 and 45-60-Mann-Whitney U test -with a higher IOP lowering in the DL group. The comparison of IOP survival curves (Log-Rank test) was not significant p = 0.070809. Ocular hypertension, hyphema and inflammatory signs were higher in the DL group, both in short and long term, but in terms of statistical significance only ocular hypertension showed differences p = 0.00011717-Fisher exact test. Microscopic examination revealed patent sclerostomies in 60% of the MMC group eyes with different grades of fibroblastic proliferation. In the DL group we observed necrosis of the scleral stroma and of the pigmented and unpigmented ciliary epithelium, with signs of thermal coagulation of the ciliary stroma and of the stromal vasculature. We must point out that the treatment with laser has proved to be more effective although both treatments showed very acceptable IOP lowering until 2 months after the surgery.

The antiinflammatory effect of nordihydroguaiaretic acid in endotoxin induced uveitis in rabbits

The authors evaluated the anti-inflammatory effect of nordihydroguaiaretic acid (NDGA) and dexamethasone on an endotoxin induced uveitis (EIU) model, in rabbits. Six groups of 12 rabbits were formed. In groups II to V a uveitis was induced by an intravitreal injection of 5 ul of saline, containing 10 ng of endotoxin of Salmonella typhi. In group I, which is considered as the control, an intravitreal injection of 5 ul of saline was given. Each group received a different treatment and the inflammatory reaction was evaluated after 24 hours, quantifying the following parameters: clinical scoring, cells, proteins, PGE2, LTB4 in the aqueous and histopathological scoring. Compared to group II (non treated), group VI (treated with intraperitoneal 2 mg/kg dexamethasone) showed a decrease of 61% of proteins and LTB4, and a decrease of more than 90% of the other parameters studied. All these differences are statistically significant (p < 0.001). In groups III (intraperitoneal NDGA 10 mg/kg), IV and V (NDGA 1% topically every two and four hours respectively), the proteins showed a change of less than 5.5% and the PGE2 was reduced to around 50% compared to group II; these changes are not statistically significant (p > 0.05). The authors observed an important and significant decrease of the other parameters when compared to group II (p < 0.001). It can be concluded that at the doses given here, NDGA shows an effective action on the lipoxygenase pathway without an increase of the production of PGE2.

Modulation of insulin induced ornithine decarboxylase by putrescine and methylputrescines in H-35 hepatoma cells

The effect of several methylputrescines on the activity of insulin-induced ornithine decarboxylase (ODC) was examined in H-35 hepatoma cells. The induction involved both protein and m-RNA synthesis. Actinomycin D inhibited ODC activity when given up to 1 h after insulin treatment. When added to the medium 2 h or 3 h after the insulin, the activity was increased 100% and 80% respectively. Insulin-induced ODC from H-35 cells had a biphasic half-life, a shorter one of 46 min and a longer one of 90 min. 1-Methylputrescine and 2-methylputrescine were found to be competitive inhibitors of the ODC from H-35 cells with Ki values of 2.8 and 0.1 mM respectively. Putrescine itself was found to have a Ki = 2.4 mM. N-Methylputrescine was a very poor inhibitor of the cell free ODC while 1,4-dimethylputrescine did not show any inhibitory effect. When cellular ODC activity was measured, the four methylputrescines assayed as well as putrescine entirely abolished its activity in the H-35 cells when given at a 1 mM concentration together with insulin. 1-Methylputrescine and 1,4-dimethylputrescine abolished 60% of the activity at a 0.1 microM concentration. All the methylputrescines given at 0.1 mM concentrations decreased the putrescine content of the stimulated cells to the levels found in quiescent cells, but only 1-methyl and 2-methylputrescines decreased spermidine and spermine content. 1,4-Dimethyl and 1-methylputrescines showed a strong inhibition of ODC synthesis, while the other diamines were less inhibitory. At concentrations that abolished ODC activity, 1,4-dimethylputrescine decreased 70% of the total immunoreactive ODC bands, while 1-methyl and 2-methylputrescine decreased them by 50%, and N-methylputrescine and putrescine decreased them by 20%. The lack of decrease in immuno-reactive ODC with the latter two compounds was mainly due to the appearance of immunoreactive degradation products of ODC of low molecular weight. Putrescine and N-methylputrescine affected protein synthesis to a small extent in stimulated cells, while 1-methylputrescine decreased it to the level of non-stimulated cells. Insulin (1 microM concentration) stimulated DNA synthesis in the cells, and this stimulation was doubled in the presence of 2-methylputrescine or putrescine. It can be concluded that, among the methylputrescines assayed, 2-methylputrescine was the best inhibitor of cell-free ODC activity, while 1,4-dimethylputrescine and 1-methylputrescine were the best inhibitors of cellular ODC activity.