The Impact of Preexisting Myocardial Remodeling on Ventricular Function Early after Tetralogy of Fallot Repair

Background: Twenty-three patients (median age 23 months) who underwent Fallot`s tetralogy repair were investigated prospectively to detect a possible association between histopathologic myocardial remodeling and echocardiographic findings of systolic or diastolic ventricular dysfunction. Methods: Intraoperatively resected infundibular bands and subendocardial biopsy samples from the right ventricle (RV) and left ventricle were obtained for histopathologic evaluation. Tissue Doppler echocardiographic interrogation of the ventricles was performed before surgery and in the postoperative period. Results: Histopathologic data revealed hypertrophy of the RV cardiomyocytes and increased interstitial collagen in both ventricles. Mean values of RV isovolumic acceleration decreased significantly at the third evaluation compared with the preoperative values (P = .006). RV myocardial fibrosis greater than 8.3% was associated with a probability of altered E` of at least 0.7 (odds ratio = 2.31). Conclusion: Preoperative histologic myocardial remodeling influenced the postoperative RV function in this group of patients with late repair. Further studies are necessary to evaluate the myocardium in younger patients and to define its influence in the long-term follow-up. (J Am Soc Echocardiogr 2010;23:912-8.)

Stereological and allometric studies on neurons and axo-dendritic synapses in the superior cervical ganglia of rats, capybaras and horses

The superior cervical ganglion (SCG) in mammals varies in structure according to developmental age, body size, gender, lateral asymmetry, the size and nuclear content of neurons and the complexity and synaptic coverage of their dendritic trees. In small and medium-sized mammals, neuron number and size increase from birth to adulthood and, in phylogenetic studies, vary with body size. However, recent studies on larger animals suggest that body weight does not, in general, accurately predict neuron number. We have applied design-based stereological tools at the light-microscopic level to assess the volumetric composition of ganglia and to estimate the numbers and sizes of neurons in SCGs from rats, capybaras and horses. Using transmission electron microscopy, we have obtained design-based estimates of the surface coverage of dendrites by postsynaptic apposition zones and model-based estimates of the numbers and sizes of synaptophysin-labelled axo-dendritic synaptic disks. Linear regression analysis of log-transformed data has been undertaken in order to establish the nature of the relationships between numbers and SCG volume (V(scg)). For SCGs (five per species), the allometric relationship for neuron number (N) is N=35,067xV (scg) (0.781) and that for synapses is N=20,095,000xV (scg) (1.328) , the former being a good predictor and the latter a poor predictor of synapse number. Our findings thus reveal the nature of SCG growth in terms of its main ingredients (neurons, neuropil, blood vessels) and show that larger mammals have SCG neurons exhibiting more complex arborizations and greater numbers of axo-dendritic synapses.

Evaluation of platelet count by automatic blood counter QBC Vet Autoread (R) compared with blood smear estimative and count by hemocytometer

The platelet blood count in laboratorial routine provides to the clinician important information about the hemostasis of the patient. There are many techniques described, however the gold standard techniques realized in hemocytometer spent a lot of time, making this technique impracticable in great routines. This research had the intent to evaluate if the automatic veterinary blood counter QBC Vet Autoread (R), whose results get five minutes to be ready, is capable to offer a trustworthy platelet count number. To this end, were evaluated the correlations among three different forms of platelets count in dogs: count in automatic blood counter QBC Vet Autoread (R), estimative in blood smear and the gold standard method by manual count in hemocytometer. The viability and confidence use of automatic blood counters of the medicine veterinary routine. Seventeen dogs were chosen randomly way, in the medical and surgical routine of HOVET-USP. The analysis revel high correlation between the hemocytometer and the estimative in blood smear (r=0,875) and between the hemocytometer and automatic blood count by QBC Vet Autoread (R) (r=0,939). Conclude that the platelet blood cont by QBC Vet Autoread (R), in addition to be fast, it`s more truthful when compared with estimative in blood smear, although the latter one also had elevated correlation. However, morphological analysis through the smears cannot be dismissed because none of the other two techniques evaluated have the ability to assess platelet morphological changes.

Low-intensity Treadmill Exercise-related Changes in the Rat Stellate Ganglion Neurons

Stellate ganglion (SG) represents the main sympathetic input to the heart. This study aimed at investigating physical exercise-related changes in the quantitative aspects of SG neurons in treadmill-exercised Wistar rats. By applying state-of-the-art design-based stereology, the SG volume, total number of SG neurons, mean perikaryal volume of SG neurons, and the total volume of neurons in the whole SG have been examined. Arterial pressure and heart rate were also measured at the end of the exercise period. The present study showed that a low-intensity exercise training program caused a 12% decrease in the heart rate of trained rats. In contrast, there were no effects on systolic pressure, diastolic pressure, or mean arterial pressure. As to quantitative changes related to physical exercise, the main findings were a 21% increase in the fractional volume occupied by neurons in the SG, and an 83% increase in the mean perikaryal volume of SG neurons in treadmill-trained rats, which shows a remarkable neuron hypertrophy. It seems reasonable to infer that neuron hypertrophy may have been the result of a functional overload imposed on the SG neurons by initial posttraining sympathetic activation. From the novel stereological data we provide, further investigations are needed to shed light on the mechanistic aspect of neuron hypertrophy: what role does neuron hypertrophy play? Could neuron hypertrophy be assigned to the functional overload induced by physical exercise? (C) 2008 Wiley-Liss, Inc.

Ultrastructural aspects of lingual papillae in squirrel monkey (Saimiri sciureus)

Saimiri sciureus is one of the smallest Cebidae native of Amazon region and also found at the biological reserve of northeast Atlantic forest. It is an omnivore animal, with diversified diet that directly influences the lingual mucosa, which includes certain types of papillae with different organization levels. The present study attempted to describe the morphological and ultrastructure aspects of the dorsal surface of the S. sciureus. Five tongues of de S. sciureus were analyzed from three males and two females who died from natural causes and were obtained from breeding colonies of CENP-Ananindeua-PA. Main macroscopic features were a general triangular shape with a craniocaudal elongation pointed apex. Tissue samples-apex, body, and root of tongue-were fixed in modified Karnovsky solution, following standard scanning protocol, mounted in stubs, coated by gold, and analyzed by Scanning Electron Macroscopy (SEM). Four types of papillae were described: filiform (along all tissue extension with 154 mu m of diameter), fungiform (along all tissue extension with 272 mu m of diameter), vallate [just three units in caudal (dorsal) portion with 830 mu m of diameter] and foliate (one pair at caudolateral surface with similar to 13 projections and 3000 mu m in length). Data analysis indicates that the distribution and ultra structural morphology of the S. sciureus lingual papillae are some similar to other primates. Microsc. Res. Tech. 74:484-487, 2011. (C) 2010 Wiley-Liss, Inc.

Hypertrophy and neuron loss: structural changes in sheep SCG induced by unilateral sympathectomy

Recently, superior cervical ganglionectomy has been performed to investigate a variety of scientific topics from regulation of intraocular pressure to suppression of lingual tumour growth. Despite these recent advances in our understanding of the functional mechanisms underlying superior cervical ganglion (SCG) growth and development after surgical ablation, there still exists a need for information concerning the quantitative nature of the relationships between the removed SCG and its remaining contralateral ganglion and between the remaining SCG and its modified innervation territory. To this end, using design-based stereological methods, we have investigated the structural changes induced by unilateral ganglionectomy in sheep at three distinct timepoints (2, 7 and 12 weeks) after surgery. The effects of time, and lateral (left-right) differences, were examined by two-way analyses of variance and paired t-tests. Following removal of the left SCG, the main findings were: (i) the remaining right SCG was bigger at shorter survival times, i.e. 74% at 2 weeks, 55% at 7 weeks and no increase by 12 weeks, (ii) by 7 weeks after surgery, the right SCG contained fewer neurons (no decrease at 2 weeks, 6% fewer by 7 weeks and 17% fewer by 12 weeks) and (iii) by 7 weeks, right SCG neurons were also larger and the magnitude of this increase grew substantially with time (no rise at 2 weeks, 77% by 7 weeks and 215% by 12 weeks). Interaction effects between time and ganglionectomy-induced changes were significant for SCG volume and mean perikaryal volume. These findings show that unilateral superior cervical ganglionectomy has profound effects on the contralateral ganglion. For future investigations, it would be interesting to examine the interaction between SCGs and their innervation targets after ganglionectomy. Is the ganglionectomy-induced imbalance between the sizes of innervation territories the milieu in which morphoquantitative changes, particularly changes in perikaryal volume and neuron number, occur? Mechanistically, how would those changes arise? Are there any grounds for believing in a ganglionectomy-triggered SCG cross-innervation and neuroplasticity? (C) 2011 ISDN. Published by Elsevier Ltd. All rights reserved.

Evaluation of lignin contents in tropical forages using different analytical methods and their correlations with degradation of insoluble fiber

We compared the lignin contents of tropical forages by different analytical methods and evaluated their correlations with parameters related to the degradation of neutral detergent fiber (NDF). The lignin content was evaluated by five methods: cellulose solubilization in sulfuric acid [Lignin (sa)], oxidation with potassium permanganate [Lignin (pm)], the Klason lignin method (KL), solubilization in acetyl bromide from acid detergent fiber (ABLadf) and solubilization in acetyl bromide from the cell wall (ABLcw). Samples from ten grasses and ten legumes were used. The lignin content values obtained by gravimetric methods were also corrected for protein contamination, and the corrected values were referred to as Lignin (sa)p, Lignin (pm)p and KLp. The indigestible fraction of NDF (iNDF), the discrete lag (LAG) and the fractional rate of degradation (kd) of NDF were estimated using an in vitro assay. Correcting for protein resulted in reductions (P < 0.05) in the lignin contents as measured by the Lignin (sa), Lignin (pm) and, especially, the KL methods. There was an interaction (P < 0.05) of analytical method and forage group for lignin content. In general, LKp method provided the higher (P < 0.05) lignin contents. The estimates of lignin content obtained by the Lignin (sa)p, Lignin (pm)p and LKp methods were associated (P > 0.05) with all of the NDF degradation parameters. However, the strongest correlation coefficients for all methods evaluated were obtained with Lignin (pm)p and KLp. The lignin content estimated by the ABLcw method did not correlate (P > 0.05) with any parameters of NDF degradation. There was a correlation (P < 0.05) between the lignin content estimated by the ABLadf method and iNDF content. Nonetheless, this correlation was weaker than those found with gravimetric methods. From these results, we concluded that the gravimetric methods produce residues that are contaminated by nitrogenous compounds. Adjustment for these contaminants is suggested, particularly for the KL method, to express lignin content with greater accuracy. The relationships between lignin content measurements and NDF degradation parameters can be better determined using KLp and Lignin (pm)p methods. (C) 2011 Elsevier B.V. All rights reserved.

Canine population dynamics: the potential effect of sterilization campaigns

Objective. To analyze, through mathematical modeling, the potential ability of sterilization campaigns to reduce the population density of pet dogs. Methods. Mathematical models were constructed to simulate the canine population dynamics and project the results of control strategies based on several sterilization rates. Results. Even at high sterilization rates (for example, 0.80 year(-1)), it would take approximately 5 years to reduce density by 20%. Even so, other sources of population growth, such as the importing of dogs from other geographic areas, could outweigh the effects of a sterilization program. Conclusions. A program`s effectiveness is contingent upon not only on the sterilization rate, but also the rate of population growth. Sterilization campaigns may potentially reduce population density, but this reduction may not be immediately evident.

Survey for Tick-Borne Zoonoses in the State of Espirito Santo, Southeastern Brazil

Blood samples collected from 201 humans, 92 dogs, and 27 horses in the state of Espirito Santo, Brazil, were tested by polymerase chain reaction, indirect immunofluorescence assays, and indirect enzyme-linked immunosorbent assay for tick-borne diseases (rickettsiosis, ehrlichiosis, anaplasmosis, borreliosis, babesiosis). Our results indicated that the surveyed counties are endemic for spotted fever group rickettsiosis because sera from 70 (34.8%) humans, 7 (7.6%) dogs, and 7 (25.9%) horses were reactive to at least one of the six Rickettsia species tested. Although there was evidence of ehrlichiosis (Ehrlichia canis) and babesiosis (Babesia cams vogeli, Theileria equi) in domestic animals, no human was positive for babesiosis and only four individuals were serologically positive for E. canis. Borrelia burgdorferi-serologic reactive sera were rare among humans and horses, but encompassed 51% of the canine samples, suggesting that dogs and their ticks can be part of the epidemiological cycle of the causative agent of the Brazilian zoonosis, named Baggio-Yoshinari Syndrome.

Time series evaluation of traumatic lesions and airsacculitis at one poultry abattoir in the state of Sao Paulo, Brazil (1996-2005)

Ten year official condemnation records of one officially inspected poultry abattoir in state of Sao Paulo. Brazil, were analyzed. Seasonal and cyclical trends were analyzed in relation to traumatic lesions and airsacculitis. which were the most relevant official condemnation causes Time series analysis of the records, seasonal indexes and moving averages was used to describe the adherence to the mathematical model and to offer preventive management strategies for the slaughter house industry Although cause-effect relationships were not defined, some insight was given into the causal mechanisms that generated the series (C) 2010 Elsevier B V All rights reserved

Dynamics and Control of Stray Dog Populations

The population dynamics of stray dogs is simulated to assess the effects of sterilization and euthanasia. From simulations representing less than 5 years, sterilization is less efficient than euthanasia to reduce the stray dog population, considering similar rates, but the total number of sterilized dogs is less than the total number of euthanized dogs per km(2) per year. Over 20 years, both strategies have similar efficiency. Beyond a certain rate of dog abandonment, both strategies are inefficient.

Hepatozoon canis infecting dogs in the State of Espirito Santo, southeastern Brazil

From May 2007 to March 2008, blood samples were collected from 92 healthy dogs living in 21 households (17 farms in rural area, and 4 homes in urban area) in 6 counties of the State of Espirito Santo, southeastern Brazil. In addition, ticks were collected from these dogs. A mean of 4.4 +/- 3.0 dogs (range: 1-12) were sampled per household; 78 and 14 dogs were from rural and urban areas, respectively. Polymerase chain reaction (PCR) designed to amplify fragments of the 18S rDNA gene of Babesia spp or Hepatozoon spp revealed amplicons of the expected size in 20 (21.7%) dogs for Babesia, and 54 (58.7%) dogs for Hepatozoon. All Babesia-positive dogs were also Hepatozoon-positive. Among the 21 households, 15 (71.4%) from 3 counties had at least one PCR-positive dog, including 13 farms (rural area) and 2 homes (urban area). A total of 40 PCR products from the Hepatozoon-PCR, and 19 products from the Babesia-PCR were submitted to DNA sequencing. All generated sequences from Hepatozoon-PCR were identical to each other, and to corresponding 18S rDNA sequences of H. canis in GenBank. Surprisingly, all generated sequences from the Babesia PCR were also identical to corresponding 18S rDNA sequences of H. canis in GenBank. Dogs from 10 rural and 2 urban households were found infested by Rhipicephalus sanguineus ticks. Immature of Amblyomma cajennense ticks were found in dogs from only 4 rural households (also infested by R. sanguineus). All but one household with R. sanguineus-infested dogs had at least one Hepatozoon-infected dog. Statistical analysis showed that the presence of ticks (i.e. R. sanguineus) infesting dogs in the households was significantly (P < 0.05) associated with at least one PCR-positive dog. There was no significant association (P > 0.05) between PCR-positive dogs and urban or rural households. Canine hepatozoonosis caused by H. canis is a high frequent infection in Espirito Santo, Brazil, where it is possibly vectored by R. sanguineus. Since all infected dogs were found apparently healthy, the pathogenicity of H. canis for dogs in Espirito Santo is yet to be elucidated. (C) 2009 Elsevier B.V. All rights reserved.

Elevated progesterone concentrations enhance prostaglandin F(2 alpha) synthesis in dairy cows

The objective was to evaluate the influence of varying plasma progesterone (P(4)) concentrations throughout the luteal phase in dairy cows on PGF(2 alpha) production (assessed as plasma concentrations of 13,14-dihydro-15-keto-PGF(2 alpha); PGFM) following treatment with estradiol-17 beta (E(2)) or oxytocin (OT). In all experiments, time of ovulations was synchronized with the OvSynch protocol and Day 0 corresponded to day of second GnRH injection. In Experiment 1, non-lactating dairy cows on Day 6 remained non-treated (n = 9), received 20 mg LH (n = 7), or had ovarian follicles larger than 6 mm aspirated (n = 8). In Experiment 2, cows on Day 6 were untreated (n = 9) or received 5000 IU hCG (n = 10). In Experiments 1 and 2, all cows received 3 mg E(2) on Day 17, and blood samples were collected every 30 min from 2h before to 10h after E(2). Experiment 3 was conducted in two periods, each from Days 0 to 17 of the estrous cycle. At the end of Period 1, animals switched treatments in a crossover arrangement. Animals in Group 2/8 (n = 4) received 2 kg/d of concentrate in the first period and 8 kg/d in the second period. Animals in Group 8/2 (n = 7) received the alternate sequence. Blood was collected daily for measurement Of P(4) 4 h after concentrate feeding. On Day 17, blood was collected from 1 h before to 1 h after a 100 IU OT injection. In Experiment 1, both plasma P(4) and release Of PGF(2 alpha) were similar between LH-treated and control cows (P > 0.10). In Experiment 2, plasma P4 was elevated to a greater extent on Day 17 in cows treated with hCG (P < 0.05) and plasma PGFM was also greater in hCG-treated animals (treatment x time interaction; P < 0.05). In Experiment 3, there was a group x period interaction (P < 0.01) for plasma P(4), indicating that less concentrate feeding was associated with greater plasma P(4). Release of PGF(2 alpha) in response to OT was greater for cows receiving less concentrate (group x period interaction; P < 0.05). In conclusion, dairy cows with more elevated blood P(4) concentrations released more PGF(2 alpha) in response to E(2) or OT. (c) 2008 Elsevier B.V. All rights reserved.

Tracking the Ovarian Cycle in Black-and-Gold Howlers (Alouatta caraya) by Measuring Fecal Steroids and Observing Vaginal Bleeding

A better understanding of a species` reproductive physiology can help conservation programs to manage primates in the wild and develop assisted reproductive technologies in captivity. We investigated whether measurements of fecal progestin and estrogen metabolites obtained by a radioimmunoassay could be used to monitor the ovarian cycle of Alouatta caraya. We also compared the occurrence of vaginal bleeding with the hormone profiles. We collected fecal samples from 3 adult and 1 subadult captive female over 5 mo and performed vaginal cytology for the adults. The interval between fecal progestin surges in the adult females was 19.11 +/- 2.14 d (n = 18 cycles). Fecal progestin concentrations remained at basal values for 9.83 +/- 2.21 d (n = 18) and rose to elevated values for 9.47 +/- 0.72 d (n = 19). The subadult female showed basal levels of fecal estrogen and progestin concentrations throughout the study, suggesting that our hormone measurements are valid to monitor the ovarian cycle. Bleeding periods coincided with basal levels of fecal estrogens and progestin at intervals of 19.8 +/- 0.9 d and lasted for 4.1 +/- 1.0 d. Although we obtained these data from only 3 individuals, the results indicate that this species likely has a menstrual-type ovarian cycle. These data provide the first endocrine profile for the Alouatta caraya ovarian cycle and are similar to results obtained for other howler species. This similarity is important for comparative studies of howlers, allowing for a better understanding of their reproductive physiology and contributing to a critical information base for managing Alouatta species.

The Developing Left Superior Cervical Ganglion of Pacas (Agouti Paca)

In this study the main question investigated was the number and size of both binucleate and mononucleate superior cervical ganglion (SCG) neurons and, whether post-natal development would affect these parameters. Twenty left SCGs from 20 male pacas were used. Four different ages were investigated, that is newborn (4 days), young (45 days), adult (2 years), and aged animals (7 years). By using design-based stereo-logical methods, that is the Cavalieri principle and a physical disector combined with serial sectioning, the total volume of ganglion and total number of mononucleate and binucleate neurons were estimated. Furthermore, the mean perikaryal (somal) volume of mononucleate and binucleate neurons was estimated using the vertical nucleator. The main findings of this study were a 154% increase in the SCG volume, a 95% increase in the total number of mononucleate SCG neurons and a 50% increase in the total volume of SCG neurons. In conclusion, apart from neuron number, different adaptive mechanisms may coexist in the autonomic nervous system to guarantee a functional homeostasis during ageing, which is not always associated with neuron losses. Anat Rec, 292:966-975, 2009. (C) 2009 Wiley-Liss, Inc.