Fighting by sleep-deprived rats as a possible manifestation of panic: effects of sodium lactate

Increased fighting is an effect of desynchronized sleep deprivation (DSD) in rats, and recently this behavior has been suggested to be spontaneous panic and equivalent to panic disorder. In the present study we tested this hypothesis by evaluating the effect of sodium lactate on this aggressiveness, because this substance is recognized to induce spontaneous panic attacks in patients. A total of 186 male albino Wistar rats, 250-350 g, 90-120 days of age, were submitted to DSD (multiple platform method) for 0, 4, or 5 days. At the end of the deprivation period the rats were divided into subgroups respectively injected intraperitoneally with 1.86, 2.98 and 3.72 g/kg of 1 M sodium lactate, or 1.86 and 3.72 g/kg of 2 M sodium lactate. The control animals were submitted to the same procedures but received equivalent injections of sodium chloride. Regardless of DSD time, sleep-deprived animals that received sodium lactate presented a significantly higher mean number of fights (0.13 ± 0.02 fights/min) and a longer mean time spent in confrontation (2.43 ± 0.66 s/min) than the controls (0.01 ± 0.006 fights/min and 0.12 ± 0.07 s/min, respectively; P<0.01, Student t-test). For the sodium lactate group, concentration of the solution and time of deprivation increased the number of fights, with the mean number of fights and mean duration of fighting episodes being greater with the 2.98 g/kg dose using 1 M lactate concentration. These results support the hypothesis that fighting induced by DSD is probably a spontaneous panic manifestation. However, additional investigations are necessary in order to accept this as a promising animal model for studies on panic disorder.

Effect of temperature and leaf wetness duration on infection of sweet oranges by Asiatic citrus canker

Asiatic citrus canker, caused by Xanthomonas smithii ssp. citri, formerly X. axonopodis pv. citri, is one of the most serious phytosanitary problems in Brazilian citrus crops. Experiments were conducted under controlled conditions to assess the influence of temperature and leaf wetness duration on infection and subsequent symptom development of citrus canker in sweet orange cvs Hamlin, Natal, Pera and Valencia. The quantified variables were incubation period, disease incidence, disease severity, mean lesion density and mean lesion size at temperatures of 12, 15, 20, 25, 30, 35, 40 and 42 degrees C, and leaf wetness durations of 0, 4, 8, 12, 16, 20 and 24 h. Symptoms did not develop at 42 degrees C. A generalized beta function showed a good fit to the temperature data, severity being highest in the range 30-35 degrees C. The relationship between citrus canker severity and leaf wetness duration was explained by a monomolecular model, with the greatest severity occurring at 24 h of leaf wetness, with 4 h of wetness being the minimum duration sufficient to cause 100% incidence at optimal temperatures of 25-35 degrees C. Mean lesion density behaved similarly to disease severity in relation to temperature variation and leaf wetness duration. A combined monomolecular-beta generalized model fitted disease severity, mean lesion density or lesion size as a function of both temperature and duration of leaf wetness. The estimated minimum and maximum temperatures for the occurrence of disease were 12 degrees C and 40 degrees C, respectively.

EFFECTS OF 2,4-DICHLOROPHENOXYACETIC ACID (2,4-D) ON OPEN-FIELD BEHAVIOR AND NEUROCHEMICAL PARAMETERS OF RATS

The effects of the herbicide 2,4-dichlorophenoxyacetic acid (2,4-D) on the central nervous system (CNS) were studied in rats. Behavioural and neurochemical studies were performed. Results show that acute and oral administration of dimethylamine 2,4-D was able to decrease locomotion and rearing frequencies and to increase immobility duration of rats observed in an open-field test. Treatment of rats with p-chlorophenylalanine (PCPA) was unable to change rat's open-field behaviour; 5-hydroxytryptophan (5-HTP) administration not only increased locomotion and rearing frequences but also decreased immobility duration. Pretreatment of the rats with PCPA and 5-HTP decreased and increased dimethylamine 2,4-D effects, respectively. The herbicide was not able to change the striatal levels of dopamine and homovanilic acid but decreased the striatal levels of serotonin (5-HT), as observed for the doses of 100 and 200 mg/kg and increased those of 5-hydroxyindoleacetic acid (5-HIAA) as measured after the 200 mg/kg dose treatment. When the levels of serotonin and 5-HIAA were measured at the brain stem level, only those of 5-HIAA were modified, being increased by diethylamine 2,4-D (60; 100 and 200 mg/kg); this increment on 5-HIAA levels was observed even 1 hr after pesticide administration. Further analysis showed that 2,4-D concentrations chromatographycally detected both in serum and brain of the intoxicated animals were dose-dependent, being found as early as 1 hr after the smaller dose of the herbicide used (10 mg/kg). The results suggest that diethylamine 2,4-D modify 5-HT functional activity within the CNS. Thus, the effects of the herbicide on open-field behaviour of rats could be attributed to a direct or indirect pesticide action on serotoninergic systems.

Gaze pursuit and arm control of adolescent males diagnosed with attention deficit hyperactivity disorder (ADHD) and normal controls: evidence of a dissociation in processing visual information of short and long duration

Three-dimensional kinematic analysis of line of gaze, arm and ball was used to describe the visual and motor behaviour of male adolescents diagnosed with attention deficit hyperactivity disorder (ADHD). The ADHD participants were tested when both on (ADHD-On) and off (ADHD-Off) their medication and compared to age-matched normal controls in a modified table tennis task that required tracking the ball and hitting to cued right and left targets. Long-duration information was provided by a pre-cue, in which the target was illuminated approximately 2 s before the serve, and short-duration information by an early-cue illuminated about 350 ms after the serve, leaving -500 ms to select the target and perform the action. The ADHD groups differed significantly from the control group in both the pre-cue and early-cue conditions in being less accurate, in having a later onset and duration of pursuit tracking, and a higher frequency of gaze on and off the ball. The use of medication significantly reduced the gaze frequency of the ADHD participants, but surprisingly this did not lead to an increase in pursuit tracking, suggesting a barrier was reached beyond which ball flight information could not be processed. The control and ADHD groups did not differ in arm movement onset, duration and velocity in the short-duration early-cue condition; in the long-duration pre-cue condition, however, the ADHD group's movement time onset and arm velocity differed significantly from controls. The results show that the ADHD groups were able to process short-duration information without experiencing adverse effects on their motor behaviour; however, long-duration information contributed to irregular movement control.

Use of homeopathic preparations in experimental studies with healthy plants

Background. The last comprehensive review of experimental research on effects of homeopathic treatments on plants was published in 1984, and lacked formal predefined criteria to assess study quality. Since then several new studies with more advanced methods have been published.Objectives: To compile a review of the literature on basic research in homeopathy with healthy plants with particular reference to studies investigating specific effects of homeopathic remedies.Methods: The literature search included English, French, German, Italian, Portuguese and Spanish publications from 1920 to April 2009, using predefined selection criteria. We included experiments with healthy whole plants, seeds, plant parts and cells. The outcomes had to be measured by established procedures and statistically evaluated. We developed a Manuscript Information Score (MIS) and included only publications which provided enough information for proper interpretation (MIS >= 5). A formallised Study Methods Evaluation Procedure (SMEP) was used to evaluate these studies, and the subgroup of studies with adequate controls to identify specific effects.Results: A total of 86 studies in 79 publications was identified, 43 studies included statistics, 29 had MIS >= 5, and 15 studies investigated the specificity of homeopathic preparations. Specific effects of decimal, centesimal and fifty millesimal potencies were found including dilution levels far beyond the Avogadro number. In consecutive series of potencies only some of the tested potencies showed effects. There were many individual studies with diverse methods and very few reproduction trials.Conclusions: Healthy plant models seem an useful approach to investigate basic research questions about the specificity of homeopathic preparations. More investigations with more advanced methods are recommended, especially in the sectors of potentisation techniques, effective potency levels and conditions for reproducibility. Systematic negative control experiments should become a routine procedure to control the stability of the experimental systems. Homeopathy (2009) 98, 228-243.

Recommended Guidelines for the Conduct and Evaluation of Prognostic Studies in Veterinary Oncology

There is an increasing need for more accurate prognostic and predictive markers in veterinary oncology because of an increasing number of treatment options, the increased financial costs associated with treatment, and the emotional stress experienced by owners in association with the disease and its treatment. Numerous studies have evaluated potential prognostic and predictive markers for veterinary neoplastic diseases, but there are no established guidelines or standards for the conduct and reporting of prognostic studies in veterinary medicine. This lack of standardization has made the evaluation and comparison of studies difficult. Most important, translating these results to clinical applications is problematic. To address this issue, the American College of Veterinary Pathologists' Oncology Committee organized an initiative to establish guidelines for the conduct and reporting of prognostic studies in veterinary oncology. The goal of this initiative is to increase the quality and standardization of veterinary prognostic studies to facilitate independent evaluation, validation, comparison, and implementation of study results. This article represents a consensus statement on the conduct and reporting of prognostic studies in veterinary oncology from veterinary pathologists and oncologists from around the world. These guidelines should be considered a recommendation based on the current state of knowledge in the field, and they will need to be continually reevaluated and revised as the field of veterinary oncology continues to progress. As mentioned, these guidelines were developed through an initiative of the American College of Veterinary Pathologists' Oncology Committee, and they have been reviewed and endorsed by the World Small Animal Veterinary Association.

Efficacy, safety and tolerability of terbinafine for Tinea capitis in children: Brazilian multicentric study with daily oral tablets for 1, 2 and 4 weeks

Background: Tinea capitis is a common skin disease seen predominantly in children. The standard therapies for this disease are griseofulvin and ketoconazole. Nevertheless, these drugs have drawbacks in that they are only fungistatic and require treatment for at least 6 weeks. Previous studies with oral terbinafine for the treatment of Tinea capitis have shown that this agent is effective when given for 4 weeks, comparable to an 8-week regimen with griseofulvin. To date there is no data on the use of oral terbinafine in Brazilian children. Objectives: To assess the efficacy, safety and tolerability of oral terbinafine in short-term treatments (1-, 2- and 4-week treatment) of Tinea capitis in children. Patients and methods: One hundred and thirty-two children aged 1-14 years were enrolled in this study, but only 107 were considered for the final efficacy analysis. Diagnosis included clinical assessment and examination by Wood's light. Confirmation was obtained by direct microscopy and culture for fungus. Terbinafine dosage (125 or 250 mg/day) was adjusted according to patient weight. Efficacy was evaluated both by clinical and mycological assessment. Safety and tolerability variables included data on adverse reaction and clinical laboratory evaluations. Results: Mycological evaluation in the follow-up visit at week 12 showed negative direct microscopy and culture results in 48.6, 60.5 and 69.7% patients in groups 1-, 2- and 4-week, respectively (n.s.). At week 12, 84.8% patients in group 4-week achieved clinical cure with a significant difference compared to groups 1- and 2-week, 54.3 and 60.5%, respectively (P < 0.01). Adverse reactions were present in 4.8, 6.8 and 10.9% of patients in groups 1-, 2- and 4-week, respectively. Terbinafine was not associated with clinically relevant increases in liver function tests. Conclusions: Terbinafine is an effective, well tolerated and safe antifungal agent for the treatment of Tinea capitis m children. The shorter duration of treatment resulted in lower cure rates. However, it is important to note that depending on the severity of the disease, a 1-week-only treatment can also be effective in this indication.

Electrocardiographic evolution in cats from birth to 30 days of age

Further knowledge of feline physiology and neonatology is needed because the number of cats being kept as pets and used as experimental animals has increased. Few studies have been published on feline sequential electrocardiography. This study was conducted to determine the values of normal waves, complexes, and intervals of the electrocardiogram in clinically healthy feline neonates. Serial electrocardiography was performed in 15 female and 15 male neonates at 30 days of age. Parameters analyzed were heart rate and rhythm, duration and amplitude of electrocardiographic waves, duration of intervals, and the electrical axis of the heart. The results did not show differences between males and females. During the neonates' first 30 days of life, migration of the electrical axis from right to left was observed. There was a progressive increase in the R wave amplitude, while the S wave amplitude showed a progressive decrease. A sinus heart rhythm was predominant in the feline neonates.

Effects of tiletamine/zolazepam-romifidine-atropine in ocelots (Leopardus pardalis)

Objectives: To evaluate the effects of a combination of tiletamine-zolazepam-romifidine-atropine in ocelots. Design: Prospective experimental trial. Animals: Eight captive adult ocelots (three females and five males). Methods: Calculated doses of tiletamine-zolazepam (3.75 mg kg -1), romifidine (50 μg kg-1) and atropine (0.04 mg kg-1) were administered intramuscularly. After immobilization, animals were weighed and the real doses determined. Heart rate, respiratory frequency, noninvasive systolic, diastolic, and mean arterial pressure, arterial oxygen hemoglobin saturation, and rectal temperature were measured. Data were analyzed by means of ANOVA for repeated measures, followed by the Tukey test to compare values over time. Results: Doses administered were 3.4 ± 0.6 mg kg-1 of tiletamine-zolazepam, 0.04 ± 7.0 mg kg-1 of romifidine, and 0.03 ± 0.007 mg kg-1 of atropine. The mean time to recumbency and duration of immobilization were 7.0 ± 4.5 and 109.2 ± 27.9 minutes, respectively. The median times to standing and walking were 52.3 [0-90] and 2.3 [0-69.3] minutes, respectively. A decrease in heart rate was observed 45 minutes following drug administration. Arterial blood pressure was maintained during the study. Conclusions and clinical relevance: This protocol produced good immobilization in ocelots with minimal changes over time in cardiovascular parameters.

Acute and sustained effects of early administration of inhaled nitric oxide to children with acute respiratory distress syndrome

OBJECTIVE: To determine the acute and sustained effects of early inhaled nitric oxide on some oxygenation indexes and ventilator settings and to compare inhaled nitric oxide administration and conventional therapy on mortality rate, length of stay in intensive care, and duration of mechanical ventilation in children with acute respiratory distress syndrome. DESIGN: Observational study. SETTING: Pediatric intensive care unit at a university-affiliated hospital. PATIENTS: Children with acute respiratory distress syndrome, aged between 1 month and 12 yrs. INTERVENTIONS: Two groups were studied: an inhaled nitric oxide group (iNOG, n = 18) composed of patients prospectively enrolled from November 2000 to November 2002, and a conventional therapy group (CTG, n = 21) consisting of historical control patients admitted from August 1998 to August 2000. MEASUREMENTS AND MAIN RESULTS: Therapy with inhaled nitric oxide was introduced as early as 1.5 hrs after acute respiratory distress syndrome diagnosis with acute improvements in Pao(2)/Fio(2) ratio (83.7%) and oxygenation index (46.7%). Study groups were of similar ages, gender, primary diagnoses, pediatric risk of mortality score, and mean airway pressure. Pao(2)/Fio(2) ratio was lower (CTG, 116.9 +/- 34.5; iNOG, 62.5 +/- 12.8, p <.0001) and oxygenation index higher (CTG, 15.2 [range, 7.2-32.2]; iNOG, 24.3 [range, 16.3-70.4], p <.0001) in the iNOG. Prolonged treatment was associated with improved oxygenation, so that Fio(2) and peak inspiratory pressure could be quickly and significantly reduced. Mortality rate for inhaled nitric oxide-patients was lower (CTG, ten of 21, 47.6%; iNOG, three of 18, 16.6%, p <.001). There was no difference in intensive care stay (CTG, 10 days [range, 2-49]; iNOG, 12 [range, 6-26], p >.05) or duration of mechanical ventilation (TCG, 9 days [range, 2-47]; iNOG, 10 [range, 4-25], p >.05). CONCLUSIONS: Early treatment with inhaled nitric oxide causes acute and sustained improvement in oxygenation, with earlier reduction of ventilator settings, which might contribute to reduce the mortality rate in children with acute respiratory distress syndrome. Length of stay in intensive care and duration of mechanical ventilation are not changed. Prospective trials of inhaled nitric oxide early in the setting of acute lung injury in children are needed.

Effects of long-term cyclosporin therapy on gingiva of rats--analysis by stereological and biochemical estimation.

Cyclosporin A (CsA) is used as an immunosuppressive agent and its prominent side effect is the induction of gingival overgrowth, which remains a significant problem. The risk factors appraised include the duration of treatment. However, there are no stereological and biochemical studies exploring the effects of long-term CsA therapy on gingival tissue. The purpose of the present study was to investigate the level of TGF-beta1 in saliva and describe the densities of fibroblasts and collagen fibers in the gingival tissue of rats treated with CsA for long periods. Rats were treated for 60, 120, 180 and 240 days with a daily subcutaneous injection of 10 mg/kg of body weight of CsA. At the end of the experimental periods, saliva was collected for the determination of TGF-beta1 levels. After histological processing, the oral epithelium and the connective tissue area were measured as well as the volume densities of fibroblasts (Vf) and collagen fibers (Vcf). After 60 and 120 days of CsA treatment, there was a significant increase in Vf and Vcf as well as a significant increase in TGF-beta1 levels. After 180 and 240 days, reduction in the gingival overgrowth associated with significant decreases in the level of TGF-beta1, and also decreased Vf and Vcf, were observed. The data presented here suggest that after long-term therapy, a decrease in TGF-beta1 levels occurs, which might contribute to an increase in the proteolytic activity of fibroblasts in the gingiva, favoring the normality of extracellular matrix synthesis.

Association between breast-feeding practices and sucking habits: A cross-sectional study of children in their first year of life

In addition to providing nutrition and immunological protection, breast-feeding has positive effects on the development of the infant's oral cavity. The aim of the present study is to assess breast-feeding patterns and to analyze the influence of breast-feeding practices and maternal sociodemographic variables on the prevalence of non-nutritive sucking habits in a sample of Brazilian infants. This cross-sectional study was carried out in Southern Brazil. A random sample of 100 mothers of infants up to 12 months of age was interviewed during the National Vaccination Campaign Day. The prevalence and median duration of breast-feeding were assessed. Breast-feeding practice, the exposure factor, was categorized as exclusive breast-feeding, predominant breast-feeding, complementary breast-feeding, or weaning. Maternal sociodemographic variables included age, race, marital status, educational level, profession, and family income. The outcome investigated was the prevalence of sucking habits (pacifier use and thumb sucking). We used two-sample tests, the chi-square test and Fisher exact test0 for statistical analyses of the data. The study revealed that 75% of infants were being breast-fed. Pacifier use and thumb sucking were common in 55%. Bottle-feeding was prevalent in 74% of infants. Breast-feeding was negatively correlated with pacifier use and thumb sucking (OR = 0.11; 95% CI: 0.03 to 0.4). Bottle-feeding was strongly associated with weaning (p = 0.0003). Among the sociodemographic variables, only marital status showed a statistical association with sucking habits (p = 0.04). These findings suggest that breast-feeding can prevent the occurrence of sucking habits. Although we could not evaluate causality assessment, malocclusion prevention seems to be yet one more reason for promoting breast-feeding practices.

An overview of functional and stereological evaluation of spermatogenesis and germ cell transplantation in fish

Although there are almost thirty-thousand species of fish living in a great variety of habitats and utilizing vast reproductive strategies, our knowledge of morphofunctional and quantitative aspects of testis structure and spermatogenesis is still incipient for this group of vertebrates. In this review, we discuss aspects that are important to better understanding of testis structure and function, and of the development of germ cells (GC) during spermatogenesis. To achieve this, we have recently completed a number of studies presenting morphometric and functional data related to the numbers of GC and Sertoli cells (SC) per each type of spermatogenic cyst, the number of spermatogonial generations, the SC efficiency, and the magnitude of GC loss that normally occurs during spermatogenesis. We also investigated SC proliferation and the relationship of this important event to early spermatogenic cysts. The available data strongly suggest that SC proliferation in sexually mature tilapia is the primary factor responsible for the increase in testis size and for determination of the magnitude of sperm production. The influence of temperature on the duration of spermatogenesis in tilapia was also evaluated and we have used this knowledge to deplete endogenous spermatogenesis in this teleost, in order to develop an experimental system for GC transplantation. This exciting technique results in new possibilities for investigation of spermatogenesis and spermatogonial stem cell biology, creating also an entirely new and promising scenario in biotechnology - transgenic animal production and the preservation of the genetic stocks of valuable animals or endangered species. © Springer Science+Business Media B.V. 2008.

Impulsive compulsivity in obsessive-compulsive disorder: A phenotypic marker of patients with poor clinical outcome

Although traditionally obsessive-compulsive disorder (OCD) and impulse control disorders (ICD) have represented opposing ends of a continuum, recent research has demonstrated a frequent co-occurrence of impulsive and compulsive behaviours, which may contribute to a worse clinical picture of some psychiatric disorders. We hypothesize that individuals with 'impulsive' OCD as characterized by poor insight, low resistance, and reduced control towards their compulsions will have a deteriorative course, greater severity of hoarding and/or symmetry/ordering symptoms, and comorbid ICD and/or substance use disorders (SUD). The sample consisted of 869 individuals with a minimum score of 16 on the Yale-Brown Obsessive Compulsive Scale (Y-BOCS). Of these, 65 had poor insight, low resistance, and reduced control towards compulsions ('poor IRC') and 444 had preserved insight, greater resistance and better control over compulsions ('good IRC'). These two groups were compared on a number of clinical and demographic variables. Individuals with poor IRC were significantly more likely to have a deteriorative course (p < 0.001), longer duration of obsessions (p = 0.017), greater severity of symmetry/ordering (p < 0.001), contamination/cleaning (p < 0.001) and hoarding (p = 0.002) symptoms, and comorbid intermittent explosive disorder (p = 0.026), trichotillomania (p = 0.014) and compulsive buying (p = 0.040). Regression analysis revealed that duration of obsessions (p = 0.037) and hoarding severity (p = 0.005) were significant predictors of poor IRC. In the absence of specific measures for impulsivity in OCD, the study highlights the utility of simple measures such as insight, resistance and control over compulsions as a phenotypic marker of a subgroup of OCD with impulsive features demonstrating poor clinical outcome. © 2012 Elsevier Ltd.

Physical exercise modulates peripheral levels of brain-derived neurotrophic factor (BDNF): A systematic review of experimental studies in the elderly

The objective of this study was to conduct a systematic review of studies that analyzed the effect of physical exercise on the peripheral levels of BDNF in elderly individuals. Method: We conducted a search in PsycINFO, Biological Abstracts, Pubmed, Web of Science, and Science Direct from 1990 to 2011, using the following keywords: physical exercise , physical activity , physical therapy , training , BDNF , neuroplasticity , neurotrophins , neuroplasticity proteins , aged , older , elderly The articles were considered for inclusion in the review if they were studies with elderly, assessed peripheral (serum and/or plasma) BDNF and evaluated an acute exercise or chronic exercise (training). Results: Five randomized controlled trial and one randomized non-controlled trial studies were analyzed. Five out of six studies reported a significantly higher BDNF response to aerobic acute exercise and to aerobic or strength training program in healthy elderly and elderly with different pathologies. Conclusion: It was not possible to establish a recommendation protocol for the type and intensity of physical exercise required to produce an increase in levels BDNF. However, physical exercise, particularly, moderate-intensity exercises seem to be more effective to promote increase the peripheral levels of BDNF in the elderly. © 2012 Elsevier B.V.