Extraction and characterization of collagen from the skin of Amazonian freshwater fish pirarucu.

The need to fully exploit fishing resources due to increasing production and consequent waste generation requires research to promote the sustainability of the fishing industry. Fish waste from the industry is responsible for relevant environmental contamination. However, these raw materials contain high amounts of collagen and other biomolecules, being attractive due to their industrial and biotechnological applicability. Thus, to reduce the waste from pirarucu (Arapaima gigas) processing, this study aimed to obtain collagen from pirarucu skin tissue. The extraction process used 0.05 M sodium hydroxide, 10% butyl alcohol, and 0.5 M acetic acid, with extraction temperature of 20°C. The obtained yield was 27.8%, and through sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE), it was determined that the collagen obtained was type I. This study showed that collagen solubility was highest at pH 3 and the lowest solubility was at concentrations of 3% sodium chloride. The denaturation temperature of collagen was 38.1°C, and its intact molecular structure was observed using the Fourier transform infrared spectrophotometry technique with an absorption radius of 1. The results showed that it was possible to obtain collagen from pirarucu skin at 20°C, which has the typical characteristics of commercial type I collagen. In conclusion, the procedures used may be considered to be an interesting alternative for collagen extraction, a new product obtained from the processing of fish waste.

Extraction and characterization of collagen from the skin of Amazonian freshwater fish pirarucu

The need to fully exploit fishing resources due to increasing production and consequent waste generation requires research to promote the sustainability of the fishing industry. Fish waste from the industry is responsible for relevant environmental contamination. However, these raw materials contain high amounts of collagen and other biomolecules, being attractive due to their industrial and biotechnological applicability. Thus, to reduce the waste from pirarucu (Arapaima gigas) processing, this study aimed to obtain collagen from pirarucu skin tissue. The extraction process used 0.05 M sodium hydroxide, 10% butyl alcohol, and 0.5 M acetic acid, with extraction temperature of 20°C. The obtained yield was 27.8%, and through sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE), it was determined that the collagen obtained was type I. This study showed that collagen solubility was highest at pH 3 and the lowest solubility was at concentrations of 3% sodium chloride. The denaturation temperature of collagen was 38.1°C, and its intact molecular structure was observed using the Fourier transform infrared spectrophotometry technique with an absorption radius of 1. The results showed that it was possible to obtain collagen from pirarucu skin at 20°C, which has the typical characteristics of commercial type I collagen. In conclusion, the procedures used may be considered to be an interesting alternative for collagen extraction, a new product obtained from the processing of fish waste.

Genetic diversity of Peltophorum dubium (Spreng.) Taub. progenies from the states of Minas Gerais and Mato Grosso do Sul, Brazil.

There is little information regarding the genetic diversity of native species aimed at identifying the best viable progenies for in situ and ex situ conservation. Furthermore, there is a lack of future forest improvement programs. We aimed to know the genetic diversity of 64 Peltophorum dubium (Spreng.) Taub. (Fabaceae) progenies. We determined this species' dendrometric characteristics, and when using multivariate techniques and cluster analysis, we verified the differences between the progenies and groups with less heterogeneity. The progeny and provenance test was installed in Dourados (Mato Grosso do Sul - MS), with seeds collected in three MS regions (Vale do Ivinhema, Serra de Maracaju, and Serra da Bodoquena) and in the micro-region of Lavras (Minas Gerais - MG). The experiment was conducted in an alpha lattice 8 x 8 with four repetitions. We found genetic variability among and within P. dubium populations for all height, diameter, circumference at breast height, volume, and basal area characters. We suggest that P. dubium populations have high genetic variability, which indicates possible genetic improvement through best progeny selection. The UPGMA and Tocher methods grouped the progenies into three and nine groups, respectively, in which the most divergent individuals come from MG and the Bonito region in MS. Based on morphological characters, P. dubium progenies identified as 45, 47, 49, 50, 55, and 59 from MG are the most promising, while progenies 6 and 9 were the least promising.

Kinematic characteristics of arm and trunk when drinking from a glass in children with and without cerebral palsy.

BACKGROUND: Children with cerebral palsy (CP) often have difficulty with activities that require the upper extremities secondary to deficits in strength and range of motion, spasticity, and poor timing and coordination of movement. This study aimed to identify and compare timing and coordination of the trunk and upper extremity in children with and without CP during a functional task. METHODS: Eighteen children, N = 9 with CP and N = 9 with typical development were enrolled. Participants were seated in a standard chair and instructed to drink from a glass placed at a distance of 75% of available arm length. The task was divided into 3 Phases: 1) reaching to the glass, 2) transporting the glass to the mouth, and 3) returning the glass to the table. The spatiotemporal and angular variables were analyzed with 3D kinematics of movement using a 4-camera Qualysis Motion System. FINDINGS: Children with CP demonstrated poor upper extremity timing and coordination. Despite significant trunk displacement used as a compensation in Phase 1, children with CP demonstrated a significantly lower mean velocity and velocity peak during Phases 2 and 3; and demonstrated less straight motion which required more time and movement units in all phases. INTERPRETATION: Children with CP demonstrated poor upper extremity timing and coordination when drinking (even when they successfully completed the task) measured by more trunk displacement, slower, less straight movements, and more movement units. Current rehabilitation strategies could consider training speed and use functional tasks that require different strategies across multiple phases.

Dipterofauna Associated With Rat Carcasses in the Atlantic Forest, Southeastern Brazil.

Each biome has its own fauna and intrinsic local conditions that determine the succession patterns of insects on carcasses. For this reason, regional studies are very important to forensics. This study deals with the flies that visit carcasses of Rattus rattus (L., 1758) in the Atlantic Forest remnant of Floresta da Tijuca, Rio de Janeiro, Brazil. We compare the diversity and relative abundance of fly families and species throughout the four seasons of the year and test for correlations between certain environmental variables and fly richness. In each of the four seasons, we exposed the carcasses of three rats. The carcasses were put in traps that were installed on the ground, separated by 100 m. The flies were collected from the carcasses on a daily basis, and were taken to the laboratory and kept in a climate chamber (28 °C day and 26 °C night). A total of 5,537 flies were captured, identified into 12 families: Calliphoridae (4,884 specimens), followed by Sarcophagidae, Micropezidae, Fannidae, Muscidae, Phoridae, and Neridae. Canonical correspondence and redundancy analyses of the environmental variables indicated no relationship between the seasons and fly abundance. Carcass decomposition lasted longer in the winter (12 d) than in the summer (8 d). The Margalef richness index indicated higher richness in the spring and winter, and lower richness in the summer. The Shannon-Wiener index and Simpson dominance indicated greater diversity in the spring. Diptera colonized all stages of decomposition. The families Calliphoridae and Sarcophagidae were more prevalent during the Fermentation stage. Our data have important implications for forensic entomology.

Measuring postural control during mini-squat posture in men with early knee osteoarthritis.

Studies have suggested a compromised postural control in individuals with knee osteoarthritis (OA) evidenced by larger and faster displacement of center of pressure (COP). However, quantification of postural control in the mini-squat posture performed by patients with early knee OA and its relation to muscle strength and self-reported symptoms have not been investigated. The main aim of this cross-sectional, observational, controlled study was to determine whether postural control in the mini-squat posture differs between individuals with early knee OA and a control group (CG) and verify the relation among knee extensor torque (KET) and self-reported physical function, stiffness and pain. Twenty four individuals with knee OA grades I and II (OAG) (mean age: 52.35±5.00) and twenty subjects without knee injuries (CG) (mean age: 51.40±8.07) participated in this study. Participants were assessed in postural control through a force plate (Bertec Mod. USA), which provided information about the anterior-posterior (AP) and medial-lateral (ML) COP displacement during the mini-squat, in isometric, concentric and eccentric knee extensor torque (KET) (90°/s) through an isokinetic dynamometer (BiodexMulti-Joint System3, Biodex Medical Incorporation, New York, NY, USA), and in self-reported symptoms through the WOMAC questionnaire. The main outcomes measured were the AP and ML COP amplitude and velocity of displacement; isometric, concentric, and eccentric KET and self-reported physical function, stiffness and pain. No significant differences were found between groups for postural control (p>0.05). Significant lower eccentric KET (p=0.01) and higher scores for the WOMAC subscales of pain (p=<0.001), stiffness (p=0.001) and physical function (p<0.001) were found for the OAG. Moderate and negative correlations were found between the AP COP amplitude of displacement and physical function (ρ=-0.40, p=0.02). Moderate and negative correlations were observed between the AP COP velocity of displacement and physical function (ρ=0.47, p=0.01) and stiffness (ρ=-0.45, p=0.02). The findings of the present study emphasize the importance of rehabilitation from the early degrees of knee OA to prevent postural instability and the need to include quadriceps muscle strengthening, especially by eccentric contractions. The relationship between the self-reported symptoms and a lower and slower COP displacement suggest that the postural control strategy during tasks with a semi-flexed knee should be further investigated.

THE INTAKE OF FIBER MESOCARP PASSIONFRUIT (PASSIFLORA EDULIS) LOWERS LEVELS OF TRIGLYCERIDE AND CHOLESTEROL DECREASING PRINCIPALLY INSULIN AND LEPTIN.

BACKGROUND: Diabetes mellitus (DM) is a major risk factor for coronary artery disease, renal failure, retinopathy, and neuropathy. Over the last years, there has been an increasing demand in folk medicine for natural sources that could help in the treatment of chronic diseases, including diabetes. The rind of passion fruit (Passiflora edulis f. Flavicarpa) is traditionally used as a functional food due to its high concentration of soluble and insoluble fiber. OBJECTIVE: The aim of this study was to determine the effect of high-fiber diet albedo of passion fruit on the metabolic and biochemical profile in diabetic rats induced by alloxan (2%). DESIGN: The passion fruit mesocarp fiber was dried in an oven with circulating air at 60°C and pulverized. We used 32 adult male rats, divided into 4 groups: Wistar group 1 control (GC), Wistar group 2, 15% fiber (GF15), Wistar group 3, 30% fiber (GF30), Wistar group 4, fiber disolved in water (GFH2O). The ratio of passion fruit was prepared according to the AIN 93M guidelines, varying only the source of dietary fiber. The corresponding diet for each group was offered to the animals for 60 days. RESULTS: There was a statically significant decrease in plasma glucose for GFH2O, GF15%, and GF30% groups with 27.0%, 37.4%, and 40.2%, respectively. CONCLUSION: The use of mesocarp fiber of passion fruit at concentrations of 15% and 30% are an important dietary supplement for the treatment of DM due to its potential hypoglycemic effect, and its ability to reduce triglycerides and VLDL-cholesterol levels with a principal reduction of insulin and leptin.

Avaliação de potenciais interações medicamentosas em prescrições de pacientes internadas, em hospital público universitário especializado em saúde da mulher, em Campinas-SP / Potential drug interaction evaluation in medical prescriptions in a public hospital specialized in women care, in Campinas, SP

Interação medicamentosa (IM) é um evento clínico em que os efeitos de um fármaco são alterados pelo uso concomitante ou anterior à ingestão de outro fármaco, alimento ou bebida. O estudo teve como objetivo identificar IM em prescrições da Unidade de Terapia Intensiva (UTI) e do Alojamento Conjunto (AC). Foram avaliadas 36 prescrições da UTI e 274 do AC e as IM foram listadas como "maiores", "moderadas" e "menores", tendo por base o site Drugs.com. Na UTI, foram identificadas 105 interações maiores, 171 moderadas e 18 menores. Na AC, foram identificadas 64 interações maiores, 64 interações moderadas e 4 interações menores. Para as IM classificadas como "maiores", realizou-se estudo comparativo com a base DrugDex/Micromedex® e com o software OPharmacêutico®, constatando-se que a IM de metoclopramida com tramadol, que representava 63,16% das IM da UTI e 100% das IM do AC, não são classificadas como "maiores". A identificação de IM, de relevância clínica, e o seu monitoramento permitem tratamentos mais efetivos com o menor número possível de complicações causadas por IM, diminuindo o tempo de internação e, consequentemente, os custos do hospital.

Drug interaction (DI) is a common clinical occurrence, in which the effects of one drug are altered by the simultaneous or previous use of another drug, food or drink. The aim of this study was to identify DI in medical prescriptions issued in the intensive care unit (ICU) and common shelter (CS) at a public women?s hospital in Brazil. Thirty-six prescriptions from the ICU and 271 prescriptions from the CS were analyzed and the DIs classified as "major", "moderate" and "minor", based on the database at the website Drugs.com. At the ICU, 105 "major", 171 "moderate" and 18 "minor" DIs were identified, while at the CS, the numbers found were 64, 64 and 4, respectively. For major DIs, a comparative analysis was carried out with another database, DrugDex/MicromedexTM, and the program OPharmaceuticoTM, revealing a lack of standardization and conflicting information in the different databases. Pharmacosurveillance in the wards, carried out by a pharmacist to identify the clinically relevant DIs and monitor their clinical manifestations, would enable more effective treatments to be given, with the smallest possible number of complications due to DIs, thus reducing lengths of stay and hospital costs.

Relationship of neutrophil phagocytosis and oxidative burst with the subgingival microbiota of generalized aggressive periodontitis.

INTRODUCTION: Polymorphonuclear neutrophil (PMN) dysfunctions have been associated with severe forms of periodontitis. This study evaluated the correlation between PMN phagocytosis and oxidative burst with the subgingival microbiota of patients with generalized aggressive periodontitis (GAgP). METHODS: Heparinized peripheral blood samples were obtained from 18 GAgP patients and 11 periodontally healthy (PH) subjects, and PMNs were isolated on a Ficoll-Hypaque gradient. For phagocytosis analysis, PMNs were incubated with fluorescein-labeled Staphylococcus aureus. The oxidative burst was evaluated by incubation of PMNs with dihydroethidium and activation by S. aureus. The assays were examined using flow cytometry. Subgingival biofilm samples were obtained from periodontal sites with and without periodontitis and 24 species were detected by checkerboard. RESULTS: A significantly lower phagocytosis rate was observed for patients with GAgP compared with PH subjects over time (P < 0.05). No differences between groups were found for superoxide production. GAgP patients presented significantly higher prevalence and levels of Porphyromonas gingivalis, Tannerella forsythia, and Aggregatibacter actinomycetemcomitans serotype b than controls (P < 0.05). Significant negative correlations between T. forsythia and P. gingivalis and PMN functions were observed. CONCLUSIONS: GAgP subjects presented diminished phagocytic activity of peripheral PMNs and high prevalence and levels of classical periodontal pathogens.

Dois métodos diferentes para análise cinemática dos movimentos de cabeça durante a coordenação viso-cefálica de lactentes / Two different methods for kinematic analysis of head movements relating to eye-head coordination in infants

CONTEXTUALIZAÇÃO: A análise cinemática é um método de avaliação quantitativa empregada em diferentes áreas de estudo. Na área do desenvolvimento motor, essa análise pode proporcionar uma melhor compreensão da aquisição e do desenvolvimento das habilidades motoras. OBJETIVOS: Desenvolver e comparar dois arranjos experimentais para análise cinemática dos movimentos de cabeça durante a coordenação viso-cefálica (CVC) em lactentes. MATERIAIS E MÉTODOS: Foram testados dois arranjos experimentais (A e B) que diferiam quanto ao número e posicionamento das câmeras, bem como quanto ao volume do sistema de calibração. RESULTADOS: A acurácia dos dois arranjos experimentais foi de 2,47mm, indicando que ambos podem fornecer uma reconstrução verossímil do movimento. As três câmeras usadas no arranjo B favoreceram a visualização de toda a amplitude do movimento por pelo menos uma das câmeras. Isso levou à melhora da análise qualitativa e à redução do tempo de processamento dos dados quantitativos, reduzindo-o em 33 por cento quando comparado ao arranjo A. Além disso, o arranjo B apresentou melhor relação custo-benefício. CONCLUSÕES: Ambos os arranjos são adequados para a análise cinemática dos movimentos de cabeça durante a CVC de lactentes, entretanto, o arranjo B é mais vantajoso. A metodologia do arranjo B pode ser empregada em estudos que investigam o movimento de cabeça de lactentes, sejam eles típicos ou atípicos. Os resultados de tais estudos poderão ser empregados para complementar a avaliação de lactentes de risco e, conseqüentemente, auxiliar na intervenção precoce destes.

BACKGROUND: Kinematic analysis is a method for quantitative assessment applied in different fields of study. In the field of motor development, this analysis may promote better understanding of the acquisition and development of motor skills. OBJECTIVE: To develop and compare two experimental set-ups for kinematic analysis of head movements relating to eye-head coordination (EHC) in infants. METHODS: Two experimental set-ups (A and B) were tested. They differed from each other regarding the numbers and locations of the cameras, and regarding the volume of the calibration system. RESULTS: The accuracy of the two experimental set-ups was 2.47mm, thus indicating that both can provide realistic reconstructions of the movement. The three cameras used in set-up B made it possible to view the full range of motion with at least one of the cameras. This led to improvement of the qualitative analysis and reduction of the time taken to process quantitative data, which was 33 percent shorter than seen with set-up A. In addition, set-up B presented a better cost-benefit relationship. CONCLUSIONS: Although both set-ups were adequate for kinematic analysis of head movements relating to EHC in infants, set-up B is more advantageous. The methodology for set-up B can be used in studies investigating head movements in either typical or atypical infants. The results from such studies could be used to complement assessments on at-risk infants and consequently could assist in implementing early interventions.

Influência do nível de habilidade e posição corporal no alcance de lactentes / Influence of skill level and body position on infants reaching

CONTEXTUALIZAÇÃO: Embora o desenvolvimento do alcance em diferentes posições corporais tem sido amplamente estudado, há poucas pesquisas sobre este assunto, considerando o nível de habilidade do lactente. Objetivo: Verificar como as posições corporais afetam os ajustes proximais e distais do alcance manual de lactentes de quatro a seis meses. MATERIAIS E MÉTODOS: Dez lactentes classificados como menos (n=6) e mais habilidosos (n=4) foram avaliados no mês de aquisição do alcance (M1) e após um mês de prática espontânea (M2), nas posições supina (0º), reclinada (45º) e sentada (70º). Foram analisados os ajustes proximais (alcances uni ou bimanuais) e distais (mão aberta, semi-aberta ou fechada), posição das mãos no início do movimento (perto ou longe do corpo) e movimentos de preensão. RESULTADOS: Houve predomínio de alcances unimanuais para os lactentes mais habilidosos. Os lactentes menos habilidosos apresentaram maior freqüência de alcances unimanuais em M1 (sentado) e M2 (supino e sentado). Houve predomínio de alcances com as mãos semi-abertas, exceto para lactentes mais habilidosos em M2 na posição reclinada. Lactentes menos habilidosos apresentaram mãos próximas ao corpo em M1 (reclinado e sentado) e M2 (reclinado), enquanto os mais habilidosos iniciaram seus alcances com as mãos longe do corpo em M2 (supino). Lactentes mais habilidosos fizeram mais alcances seguidos de preensão em M2 nas posições supina e sentada. CONCLUSÕES: A posição corporal afeta os ajustes proximais e distais do alcance, de acordo com o nível de habilidade do lactente.

BACKGROUND: Although the development of reaching under different body position conditions has been widely studied, little research has addressed this issue considering the infant's skill level. OBJECTIVE: To investigate how different body positions affect proximal and distal reaching adjustments among four to six-month-old infants. Methods: Ten infants classified as less (n=6) and more skilled (n=4) were evaluated both in the month when they acquired reaching abilities (M1) and after one month of spontaneous practice (M2), in the supine (0º), reclined (45º) and seated (70º) positions. Proximal (one or two-hand reaching) and distal (open, half-open or closed hand) adjustments, arm starting position (next to or away from the body) and grasping movements were analyzed. RESULTS: One-hand reaching predominated among the more skilled infants. Less skilled infants showed higher frequency of one-hand reaching in M1 (seated) and M2 (supine and seated). Reaching with the hands half-open predominated, except among the more skilled infants in M2 in the reclined position. The less skilled infants presented hands next to the body in M1 (reclined and seated) and in M2 (reclined), while the more skilled ones started their reaching with hands away from the body in M2 (supine). The more skilled infants performed more reaching followed by grasping in M2, in the supine and seated positions. CONCLUSIONS: Body position affects proximal and distal adjustments to reaching maneuvers, according to the infant's skill level.

Topical anesthesia versus sub-Tenon block for cataract surgery: surgical conditions and patient satisfaction.

PURPOSE: To compare the surgical conditions and complications and patient and surgeon satisfaction in cataract surgery by phacoemulsification under topical anesthesia (TA) versus sub-Tenon block (STB). METHODS: Prospective randomized comparative blind study, without placebo control. Patient satisfaction evaluated by the Iowa Satisfaction with Anesthesia Scale (ISAS). RESULTS: The authors prospectively enrolled 59 patients (61% female) in the study, who were randomized into groups: 26 in the TA group and 33 in the STB. There was no statistically significant difference between the groups in terms of age, sex, waiting time for surgery, ASA (American Society of Anesthesiologists) state, eye laterality, cataract density, pupillary dilation, or surgery duration, but patient collaboration was better in the STB group. We found a mean 2.2 mmHg post-anesthetic rise in intraocular pressure in the STB group, with normalization at 24 hours, and no rise in the TA group. Subconjunctival hemorrhage and chemosis were more prevalent in the STB group, and the improvement of visual acuity was similar in both groups. Subjective satisfaction with the anesthetic technique, both for the surgeon and for the patient, was more elevated in the STB group. The final ISAS scores were 1.87 in the TA group and 2.71 in the STB (p<0.005). CONCLUSIONS: The data indicate that more significant anesthesia and analgesia was achieved with the STB, leading to more favorable surgical conditions and enhanced patient and surgeon satisfaction.

Early control of reaching: effects of experience and body orientation.

Although research suggests that experience may be a better indicator of the acquisition of certain abilities by infants than age, little work addresses this issue in the development of reaching movements in particular. This longitudinal study fills this gap by verifying the effect of practice time on more- and less-skilled reachers of the same age group in different body orientations. Less- (n=6) and more-skilled (n=4) reachers were evaluated at the acquisition of reaching and again after 1 month of spontaneous practice. Kinematic analyses examined 3D wrist motion during reaching trials in supine (0 degrees ), reclined (45 degrees ) and seated (70 degrees ) orientations. The results indicated that skill level was a relevant factor in dealing with gravitational constraints imposed by different body orientations. Time of practice affected the way less- and more-skilled reachers explored and adapted the kinematic parameters of reaching to constraints imposed by body orientations. These findings suggest that not only age, but also experience and body orientations are important constraints that should be taken into account when examining infant reaching development.

Spatio-temporal parameters in infant's reaching movements are influenced by body orientation.

Many studies have demonstrated that the seated position is more effective in promoting reaching movements when compared with supine. The aim of this longitudinal study was to verify the effect of seated and supine positions on spatio-temporal parameters of reaching in 4-6-month-old infants. Four infants were observed during reaching trials in both positions. A total of 235 reaches were analyzed by using the 3D movement reconstruction. Our results showed that frequency of reaching and straightness index increased over age. Significant differences between the positions were observed at 4 months, when the frequency increased and the duration and deceleration time decreased in the seated position. There were no significant differences at 5 and 6 months. These findings suggest that young infants are able to change kinematical parameters of reaching to adapt themselves to intrinsic and extrinsic constraints (i.e. age and position).

Utilização do sistema Dvideow na analise cinematica do alcance manual de lactentes / Utilization of the Dvideow system in kinematic analysis of infants reaching movements

A analise cinematica tem sido utilizada como metodo de avaliacao para aumentar os conhecimentos sobre aquisicao e o desenvolvimento do alcance manual em lactentes. Metodos: quatro lactentes com idade de 4 a 6 meses (5+- 0,816) serviram como modelos para a adaptacao dessa metodologia. A condicao experimental consistiuna apresentacao de um brinquedo, na altura dos ombros dos lactentes. As avaliacoes foram filmadas e analisadas pelo sistema Dvideow. Foram testados o numero e a localizacao das cameras e dos iluminadores, alem do posicionamento e tamanho dos marcadores. Resultados: foi necessario utilizar, no minimo, 3 cameras digitais. A fim de possibilitar uma analise simultanea de ambos os membros superiores, uma das cameras foi posicionada atras e acima dos lactentes, enquanto duas outras foram colocadas nas laterais direita e esquerda. Para garantir a reflexao dos marcadores, foi necessario iluminar o lactente indiretamente, pois a luz direta interferia em seu comportamento. Marcadores esfericos de 0,5 cm proporcionaram maior precisao durante a analise. Os resultados obtidos foram apresentados de acordo com a trajetoria linear e angular de 10 alcances avaliados. Conclusao: Essa metodologia permite a analise cinematica do movimento de lactentes, a qual pode ser extremamente util para a compreensao do alcance de lactentes saudaveis

Development of NADPH-diaphorase in the avian retina: regulation by calcium ions and relation to nitric oxide synthase.

Nitric oxide plays an important role as an intercellular messenger in the CNS. In the present work we measured NADPH-diaphorase activity, which is considered to be a marker of cells producing nitric oxide, in homogenates of the developing chick retina. The enzyme activity can be detected beginning in 8-day-old embryonic retinas with no further quantitative variations throughout development. Arginine analogues inhibit approximately 65% of the activity in embryonic retinas and 50% in posthatched retinas. The enzyme is stimulated 50% by 2 mM calcium chloride in retinas from 8 to 14 embryonic days, but this effect decreases to 20% in 17-day embryonic retinas and practically disappears in posthatched animals. The stimulation by calcium is completely blocked by arginine analogues. The decrease in enzyme activity at posthatched retinas is not due to stimulation by endogenous calcium or the presence of insufficient amounts of calmodulin, because addition of EGTA or calmodulin, respectively, did not restore the stimulation to levels observed at embryonic stages. Inhibition of NADPH-diaphorase activity by NG-nitro-L-arginine or L-NG-(iminoethyl) ornithine is concentration dependent with IC50 values of approximately 1 mM at all stages studied. However, in the presence of calcium, the inhibition by both analogues is shifted to the left and is apparently biphasic at all developmental stages, including in posthatched animals, with IC50 values in the low micromolar range. NADPH-diaphorase was also detected by histochemistry in specific groups of cells in the early embryonic retina and in subsets of amacrine and ganglion cells, as well as in photoreceptors, in more developed retinas. The results indicate that different isoforms of nitric oxide synthase are present in the chick retina and that a calcium-dependent isoform is predominant in early periods of development.

Developmental regulation of adenosine A1 receptors, uptake sites and endogenous adenosine in the chick retina.

Although adenosine A1 receptors mediate the inhibition of dopamine-dependent stimulation of adenylate cyclase activity in the developing chick retina, their localization and function are unknown. We have examined the localization of these receptors, and of endogenous adenosine and adenosine uptake sites at several stages of chick retinal development. A1 receptors were already localized predominantly to plexiform regions by embryonic day 12 (E12) with no gross changes at subsequent stages. Adenosine immunoreactivity was absent from retina at E8 but was detected at E12 in the ganglion cell layer, as well as cells in the inner nuclear cell layer and photoreceptors. At more advanced developmental stages the immunoreactivity was greater, but displayed similar localizations. Uptake sites labeled with [3H]nitrobenzylthioinosine (NBI) were detected even earlier using binding and autoradiographic methods. [3H]NBI binding was saturable, and Scatchard analysis demonstrated a single class of sites with a Kd of 0.91 nM and Bmax of 298 fmol/mg protein in E15 retinal membranes. The binding was displaced by unlabeled NBI and dipyridamole. NBI binding sites differentiated earlier than adenosine A1 receptors or endogenous adenosine immunoreactivity, showing a diffuse distribution at E8, but predominating in the plexiform layers of more developed retinas. The results indicate that elements of a putative purinergic system differentiate at specific localizations early in retinal development.

Diagnosis of enterovirus 70 infection by demonstration of IgM antibodies.

Since outbreaks of severe acute hemorrhagic conjunctivitis occur worldwide [Hierholzer and Hatch, 1985] and the majority of the epidemics are caused by enterovirus 70 (EV-70), we developed an EV-70 IgM ELISA to simplify the diagnosis of these outbreaks. The test is based on the capture antibody technique and the use of monoclonal antibodies to EV-70. We detected EV-70 IgM antibodies in 55% of 76 convalescent-phase sera from an outbreak of acute hemorrhagic conjunctivitis in a Brazilian community. Among the 71 acute- and convalescent-phase serum pairs from this outbreak, 49 (69%) demonstrated a 4-fold or greater rise in neutralizing antibody-titer. The titer of IgM antibody began to drop by the fifth week after onset of illness. EV-70 IgM antibodies were not detected in 53 serum pairs with a 4-fold or greater rise in antibodies to other picornaviruses. The EV-70 ELISA proved to simple and relatively rapid to perform, appeared to be specific, and should be sensitive enough to diagnose outbreaks of EV-70 when multiple serum specimens can be tested.