Proof-of-Principle Direct Measurement of Landau Damping Strength at the Large Hadron Collider with an Antidamper.

Landau damping is an essential mechanism for ensuring collective beam stability in particle accelerators. Precise knowledge of the strength of Landau damping is key to making accurate predictions on beam stability for state-of-the-art high-energy colliders. In this Letter, we demonstrate an experimental procedure that would allow quantifying the strength of Landau damping and the limits of beam stability using an active transverse feedback as a controllable source of beam coupling impedance. In a proof-of-principle test performed at the Large Hadron Collider, stability diagrams for a range of Landau octupole strengths have been measured. In the future, the procedure could become an accurate way of measuring stability diagrams throughout the machine cycle.

Muscle Quality Is Associated with History of Falls in Octogenarians.

OBJECTIVES: The aim of this study was to compare muscle quality (MQ) between octogenarians classified as non-fallers, fallers and recurrent fallers and identify confounding intrinsic and extrensic factors that impact likelihood for falls. DESIGN: This observational, descriptive, cross-sectional study included older adults (N=220) aged 80 years or older. MEASUREMENTS: The Short Physical Performance Battery (SPPB) was used to evaluate physical function and MQ was calculated using the ratio of grip strength to arm muscle mass (in kilograms) quantified by DXA. Variables related to sociodemographic, clinical, cognitive function, and falls were evaluated using a questionnaire and symptoms of depression were evaluated by the Geriatric Depression Scale (GDS). A Kruskal-Wallis H test was used to verify differences between groups. Binomial logistic regression was performed to determine the impact of age, depression, polypharmacy, balance, MQ, and sex on participants having more than four falls in their history. RESULTS: Increasing MQ was associated with reduced likelihood of more than four falls in their history. Non-fallers were statistically younger (p = 0.012) and took more medications (p = 0.023) than recurrent fallers. Recurrent fallers had lower MQ when compared with fallers (p = 0.007) and non-fallers (p = 0.001) and had a lower GDS score when compared with fallers (p = 0.022). Finally, fallers presented lower scores for balance when compared to non-fallers (p = 0.013). CONCLUSION: A higher MQ is associated with a reduction in the likelihood falls in octogenarians. Therefore, it may be advantageous for clinicians to evaluate MQ when the screening of the risk of falls in older adults.

Infection Patterns of Helminths in Norops Brasiliensis (Squamata, Dactyloidae) from a Humid Forest, Northeastern Brazil and their Relation with Body Mass, Sex, Host Size, and Season.

Climatic and ecological factors can influence the parasite load of a host. Variation in rainfall, body size, and sex of the hosts may be related to the abundance of parasites. This study investigated the helminth fauna associated with a population of Norops brasiliensis, together with the effect of host biology (sex, body size, and mass) and variation in rainfall regime on the abundance of helminths. Species of three groups of endoparasites were found (Nematoda, Cestoda, and Trematoda), with nematodes as the most representative taxa with eight species, prevalence of 63.2 %, mean intensity of 4.0 ± 0.58 (1 - 25), and mean abundance of 2.66 ± 0.44 (0 - 25). Nine helminth species are new host records for N. brasiliensis. The nematode Rhabdias sp. had the highest prevalence (53.3 %). There was no signifi cant relationship between abundance of the trematode Mesocoelium monas and host sex or season, although the abundance of this parasite increased significantly with host body size and mass, while abundance of nematodes was related to season and host mass. This study increases the knowledge about the diversity of helminth fauna associated with N. brasiliensis, revealing infection levels of hosts from northeastern Brazil.

Intercostal celiotomy for removal of proventriculus foreign body in muscovy duck (Cairina moschata): case report / Celiotomia intercostal para remoção de corpo estranho do proventrículo de pato-do-mato (Cairina Moschata): relato de caso]

Ducks, geese and swans are included in the Anatidae family, Anseriformes order. The leading injuries causes to waterfowl are tangling in fishing materials and foreign bodies ingestion. A muscovy duck (Cairina moschata) was referred for treatment at Veterinary Teaching Hospital and a radiographic examination showed the presence of a hook in the coelom. Surgical exposure and incision of the proventriculus was made through left intercostal access and the hook along with a fishing line were gently removed. The animal began to feed voluntarily at the fourth post-operative day and two weeks after the procedure the patient was clinically well and was released to wild. This surgical approach differs in some aspects from the listed techniques in the known literature. It proved to be a viable and appropriate alternative to treat this affection since it did not cause any trans- or post-operative complications and enabled rapid recovery and subsequent patient release.(AU)

Patos, gansos e cisnes estão incluídos na família Anatidae, ordem Anseriformes. Entre as principais causas de ferimentos em aves aquáticas, o embaraço com materiais de pesca e a ingestão de corpos estranhos são os mais citados. Um pato-do-mato (Cairina moschata) foi encaminhado para tratamento no Hospital Veterinário e, mediante exame radiográfico, verificou-se a presença de um anzol na cavidade celomática, provavelmente no proventrículo. Utilizando-se o acesso intercostal esquerdo, foi feita a exposição e a incisão do proventrículo. Por meio dessa incisão, o anzol com um segmento de linha de pesca foi delicadamente retirado. O animal começou a se alimentar voluntariamente no quarto dia pós-operatório e duas semanas após o procedimento o paciente se encontrava clinicamente bem e apto à soltura. Esta abordagem cirúrgica difere, em alguns aspectos, das técnicas listadas na literatura e provou ser uma alternativa viável e adequada ao caso, não causando complicações e permitindo recuperação rápida, com posterior soltura do animal.(AU)

Persistent organic pollutants in juvenile Magellanic Penguins (Spheniscus magellanicus) in South America.

Magellanic penguins, Spheniscus magellanicus, are the most abundant penguins living in temperate regions of South America and are good indicators of environmental pollution in the region. Persistent organic pollutants (POPs) were detected in the liver of Magellanic penguins found debilitated or dead on the beaches of Brazil (states of Rio de Janeiro, Sao Paulo, Santa Catarina and Rio Grande do Sul) between 2008 and 2012 as well as in Uruguay and Chile in 2011. Polychlorinated biphenyls (PCBs) were more prevalent than organochlorine pesticides (DDTs ∼ HCB ∼ Drins) and polybrominated diphenyl ethers (PBDEs). Among PCBs, penta-, hexa- and hepta-chlorinated congeners were predominant. Concentrations of POPs were similar between the Pacific and Atlantic penguin populations, except for PCBs, which were relatively higher in the Pacific population. During the study years (2008-2012), large variations were found in organochlorine pesticides and PCBs tended to decline. Overall, the southern portion of South America has low concentrations of POPs, with either a constant trend or evidence of decline.

Metabotropic glutamate 5 receptor in the infralimbic cortex contributes to descending pain facilitation in healthy and arthritic animals.

The involvement of the prefrontal cortex in pain processing has been recently addressed. We studied the role of the infralimbic cortex (IL) and group I metabotropic glutamate receptors (mGluRs) in descending modulation of nociception in control and monoarthritic (ARTH) conditions. Nociception was assessed using heat-induced paw withdrawal while drugs were microinjected in the IL of rats. Local anesthesia of the IL or the adjacent prelimbic cortex (PL) facilitated nociception, indicating that IL and PL are tonically promoting spinal antinociception. Phasic activation with glutamate (GLU) revealed opposing roles of the PL and IL; GLU in the PL had a fast antinociceptive action, while in the IL it had a slow onset pronociceptive action. IL administration of a local anesthetic or GLU produced identical results in ARTH and control animals. An mGluR5 agonist in the IL induced a pronociceptive effect in both groups, while mGluR5 antagonists had no effect in controls but induced antinociception in ARTH rats. Activation of the IL mGluR1 (through co-administration of mGluR1/5 agonist and mGluR5 antagonist) did not alter nociception in controls but induced antinociception in ARTH animals. IL administration of an mGluR1 antagonist failed to alter nociception in either experimental group. Finally, mGluR5 but not mGluR1 antagonists blocked the pronociceptive action of GLU in both groups. The results indicate that IL contributes to descending modulation of nociception. mGluR5 in the IL enhance nociception in healthy control and monoarthritic animals, an effect that is tonic in ARTH. Moreover, activation of IL mGluR1s attenuates nociception following the development of monoarthritis.

Amitriptyline reverses hyperalgesia and improves associated mood-like disorders in a model of experimental monoarthritis.

Affective disorders are common comorbidities of chronic inflammatory pain that are often overlooked in primary care. As the impact of inflammatory pain upon mood-like disorders in animal models is not well known, our objective was to assess whether prolonged experimental monoarthritis (ARTH) induced the development of anxiety and depressive-like behaviours in rodents and if amitriptyline, an antidepressant commonly used in the treatment of chronic pain, could reverse both nociceptive and mood-like impairments. Experimental ARTH was induced through an injection of kaolin/carrageenan into the right knee joint with control (SHAM) animals injected with saline. Four weeks after induction, ARTH animals displayed mechanical hyperalgesia and a depressive-like phenotype as they showed a significant increase in immobility and a decrease in the latency to immobility in the forced-swimming test at the expense of the time spent climbing/swimming. ARTH animals also displayed a decreased sucrose preference, an index of anhedonia and anxiety-like behaviour as time spent exploring the open arms of the elevated-plus-maze was decreased when compared to controls. The anxiety-like phenotype was also supported by an increase in the number of fecal boli left in the open field. In ARTH animals, the administration of amitriptyline decreased mechanical hyperalgesia and increased sucrose preference and the time spent climbing, although it had a deleterious effect in the performance of control animals. Our data show that this model of ARTH can be useful for the study of chronic pain-mood disorders comorbidities and that amitriptyline is able to partly reverse the associated nociceptive and emotional impairments.

Pronociceptive changes in the activity of rostroventromedial medulla (RVM) pain modulatory cells in the streptozotocin-diabetic rat.

Neuropathic pain is one of the most frequent complications of diabetes. The increased neuronal activity of primary afferents and spinal cord neurons in streptozotocin (STZ)-diabetic rats increases the recruitment of the nociceptive ascending pathways, which may affect the activity of pain control circuits in the brain. This study aimed to characterize the electrophysiological responses of neurons of the rostroventromedial medulla (RVM), a key brainstem area involved in descending modulation of nociceptive neurotransmission at the spinal cord, in STZ-diabetic rats. Spontaneous and noxious-evoked activity of ON-like cells (pain facilitatory cells) and OFF-like cells (pain inhibitory cells) in the RVM were analyzed by single cell extracellular electrophysiological recordings in STZ-diabetic rats with behavioral signs of diabetic neuropathic pain 4 weeks after diabetes induction and in age-matched non-diabetic controls (CTRL). The electrophysiological analysis revealed an increase in the spontaneous activity of RVM pronociceptive ON-like cells in STZ-diabetic rats when compared to CTRL. On the contrary, the number of active antinociceptive OFF-like cells was significantly lower in the STZ-diabetic rats and their spontaneous activity was decreased when compared with CTRL. Overall, the changes in the activity of RVM pain modulatory cells in STZ-diabetic rats point to enhancement of descending pain facilitation. Based on similar results obtained at the RVM in traumatic neuropathic pain models, the changes in the electrophysiological responses of RVM in STZ-diabetic rats may account for exacerbated pain-like behaviors in diabetic neuropathy.

Xylanases from fungi: properties and industrial applications.

Xylan is the principal type of hemicellulose. It is a linear polymer of beta-D-xylopyranosyl units linked by (1-4) glycosidic bonds. In nature, the polysaccharide backbone may be added to 4-O-methyl-alpha-D-glucuronopyranosyl units, acetyl groups, alpha-L-arabinofuranosyl, etc., in variable proportions. An enzymatic complex is responsible for the hydrolysis of xylan, but the main enzymes involved are endo-1,4-beta-xylanase and beta-xylosidase. These enzymes are produced by fungi, bacteria, yeast, marine algae, protozoans, snails, crustaceans, insect, seeds, etc., but the principal commercial source is filamentous fungi. Recently, there has been much industrial interest in xylan and its hydrolytic enzymatic complex, as a supplement in animal feed, for the manufacture of bread, food and drinks, textiles, bleaching of cellulose pulp, ethanol and xylitol production. This review describes some properties of xylan and its metabolism, as well as the biochemical properties of xylanases and their commercial applications.

[Tubercular meningoencephalitis: evaluation of 231 cases]. / Meningoencefalite tuberculosa: avaliação de 231 casos.

This study assessed 231 cases of tuberculous meningitis of which 62 (26.8%) had diagnostic confirmation against 169 (73.2%) with only clinical picture and laboratorial indication for this diagnosis. Fifty-five percent of the sample was male; ages ranged from one month to 68 years, 42% comprising children below four years. Clinical, demographic and liquoric characteristics were investigated and compared amongst those with likely and confirmed diagnosis. In conclusion, attention is drawn to the severity of this disease with high rates of lethality mainly within the age-range of 0-4 years, and to the possibility of misdiagnosis in the presentation of acute forms and predominance of neutrophils in the liquor.

Meningoencefalite tuberculosa: avaliação de 231 casos / Tubercular meningoencephalitis: evaluation of 231 cases

This study assessed 231 cases of tuberculous meningitis of which 62 (26.8%) had diagnostic confirmation against 169 (73.2%) with only clinical picture and laboratorial indication for this diagnosis. Fifty-five percent of the sample was male; ages ranged from one month to 68 years, 42% comprising children below four years. Clinical, demographic and liquoric characteristics were investigated and compared amongst those with likely and confirmed diagnosis. In conclusion, attention is drawn to the severity of this disease with high rates of lethality mainly within the age-range of 0-4 years, and to the possibility of misdiagnosis in the presentation of acute forms and predominance of neutrophils in the liquor.

Neste estudo foram avaliados 231 pacientes com meningoencefalite tuberculosa, sendo que 62 casos tiveram diagnóstico comprovado e 169 apresentavam quadro clínico e laboratorial compatíveis com este diagnóstico. Foram 127 (55%) pacientes do sexo masculino, a idade variou de 1 mês a 68 anos, com 97 (42%) na faixa etária igual ou inferior a um ano. As características clínicas, demográficas e liquóricas foram estudadas e comparadas entre os casos confirmados e os de diagnóstico provável. Em conclusão reafirmamos a gravidade desta doença, com altas taxas de letalidade principalmente na faixa etária de zero a quatro anos e a possibilidade de erros diagnósticos nas apresentações com formas agudas e predominância de neutrófilos no líquor.

Importância e potencial utilizaçäo da sistemática filogenética em estudos de Veterinária / Importance of phylogenetic systematics and its potential use in Veterinary studies

Säo apresentados princípios básicos de sistemática filogenética, enfocando como o conhecimento das relaçöes filogenéticas de um dado grupo de animais silvestres é heuristicamente importante para resolver casos veterinários, desde tratamentos até conhecimento da anatomia dos grupos e seus constituintes

Functional alterations of the autonomic nervous system in Chagas' heart disease.

Several independent pathological studies in experimental models and in human beings showed conspicuous autonomic denervation in Chagas' disease. In spite of the inherently complex structural organization of the autonomic nervous system, the parasympathetic and sympathetic divisions are involved, as shown by many functional studies. Hence, Chagas' disease represents a unique model of impairment of the autonomic control of the heart, in absence of the nonspecific effects of cardiac failure. An improvement limitation of the studies thus far carried out is the lack of a better knowledge of the molecular biology characteristics of different strains of T. cruzi. This could explain some geographical discrepancies found in the clinical behaviour of Chagas' disease, and contribute to a better understanding of its pathophysiology.

Studies of the coronary circulation in Chagas' heart disease.

Pathogenesis of chronic Chagas' heart disease may include various disturbances in the coronary circulation, that could be responsible for the myocardial lesions seen in human hearts and in experimental models of the disease. In this paper we critically reviewed the anatomical and functional abnormalities described in chronic chagasic patients, pertaining to the so-called vascular pathogenetic theory of Chagas' disease. The epicardial coronary arteries are usually free of significant obstructive disease in nonselected groups of chagasic patients examined at autopsy or by coronary angiography. However, chagasic patients who were studied after an episode of acute myocardial infarction, show the same patterns of atherosclerotic coronary artery disease seen in the general nonchagasic population. Studies of chagasic patients with angiographically normal coronary arteries, by several scintigraphy methods, revealed myocardial perfusion abnormalities which may be caused by the microcirculatory derangements described in animals experimentally infected with the T. cruzi. Since hypoperfusion has been detected in regions with normal or mildly impaired wall motion, it is likely that the microvascular disturbances precede and may be causative mechanism for the subsequent myocardial damage. We speculate that hibernating ventricular areas may occur in chagasic patients, on the basis of the evidence gathered from these studies. Recent investigations of chronic patients with Chagas' disease and chest pain showed attenuation of the vasomotor responses to physiological and pharmacological stimuli, in the epicardial coronary arteries.

High output failure in patients with peripartum cardiomyopathy: a comparative study with dilated cardiomyopathy.

Although few studies have reported on relatively preserved ventricular function in patient with peripartum cardiomyopathy, the condition is usually believed to have the typical low-output congestive hemodynamic pattern of the dilated congestive cardiomyopathies. Two groups of patients, 14 with peripartum cardiomyopathy and 12 with dilated congestive cardiomyopathy who were matched for gender and age, were studied. They had normal blood pressure and similar New York Heart Association functional class, nutritional status, thyroid function and routine laboratory evaluation. All patients were catheterized during stable in-hospital compensation of heart failure, which was achieved by bed rest, sodium restriction, and administration of digoxin and diuretics long (more than 3 months) after delivery. Significant differences (p less than 0.05) between patients with peripartum cardiomyopathy and those with dilated congestive cardiomyopathy were observed in regard to: (1) cardiac index: 3.34 +/- 1.36 L/min/m2 versus 2.24 +/- 0.72 L/min/m2, (2) systemic vascular resistance: 1713 +/- 567 dynes.sec.cm-5 versus 2194 +/- 603 dynes.sec.cm-5, (3) right ventricular stroke work index: 8.6 +/- 4.2 g.M/m2 versus 14.8 +/- 8.2 g.M/m2 in the peripartum cardiomyopathy and the dilated congestive cardiomyopathy groups, respectively. Three of the patients with peripartum cardiomyopathy had resting cardiac index values that were even higher than the normal upper limit for our laboratory (4.5 L/min/m2): 4.80, 5.70, and 5.63 L/min/m2. They also had nearly normal left ventricular ejection fractions: 0.68, 0.41, and 0.51, respectively. These results indicate that, unlike the common dilated cardiomyopathy, the hemodynamic pattern in patients with peripartum cardiomyopathy is not homogeneous, and some patients have high-output failure and near normal left ventricular function.

[Hemodynamic study of peripartum cardiopathy following compensation of heart failure]. / Estudo hemodinâmico na cardiopatia periparto após compensação da insuficiência cardíaca.

PURPOSE: To assess hemodynamic characteristics of patients with peripartum cardiomyopathy under standardized conditions of clinical compensation of heart failure, and more than 3 months after the end of the gravidic period. PATIENTS AND METHODS: Fourteen patients with peripartum cardiomyopathy underwent left and right cardiac catheterization, under rest condition. Cardiac output was measured by the Fick method, left ventricular ejection fraction determined by contrast ventriculography, and the coronary circulation was studied angiographically. RESULTS: The hemodynamic pattern observed was variable, with 28% of the cases showing low right and left ventricular filling pressures, normal LV ejection fraction, and normal or even elevated cardiac output, with low pulmonary and systemic vascular resistance. CONCLUSION: Although the mechanisms responsible for such peculiar hemodynamic characteristics, have not been elucidated, it is likely that they are associated with more benign prognosis, as compared to other patients with peripartum cardiomyopathy, who show the low-output failure commonly seen in cases of dilated cardiomyopathy.