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.

Prevalence of Rickettsia species antibodies and Rickettsia species DNA in the blood of cats with and without fever

Rickettsia species antibodies have been detected in some cats but it is unknown whether infected cats develop clinical signs. The prevalence of Rickettsia species deoxyribonucleic acid (DNA) in blood from clinically ill cats has not been determined. The objective of this study was to determine if cats with fever (body temperature >= 102.5 degrees F [39.2 degrees C]) were more likely to have evidence of rickettsial infection than healthy, age-matched, control cats with a body temperature < 102.5 degrees F. Rickettsia species polymerase chain reaction (PCR) assays were performed to detect rickettsial DNA extracted from blood (71 paired samples), indirect immunofluorescence assays (IFA) were performed to detect serum antibodies against Rickettsia felis (90 paired samples) and Rickettsia rickettsii (91 paired samples), and the results between pairs were compared. All samples were negative for Rickettsia species DNA. More cats with fever were seropositive for R felis or R rickettsii than control cats, but results were not statistically significant. Results of this pilot study failed to show an association between Rickettsia species DNA or Rickettsia species antibodies and fever. (c) 2008 ESFM and AAFP. Published by Elsevier Ltd. All rights reserved.

GLOBAL POSTURAL REEDUCATION AND STATIC STRETCHING EXERCISES IN THE TREATMENT OF MYOGENIC TEMPOROMANDIBULAR DISORDERS: A RANDOMIZED STUDY

Objective: The purpose of this study was to compare 2 different interventions, global postural reeducation (GPR) and static stretching exercises (SS), in the treatment of women with temporomandibular disorders (TMDs). Methods: A total of 28 subjects with TMDs were randomized into 2 treatment groups: GPR, where therapy involved muscle global chain stretching, or SS, with conventional static stretching; but only 24 completed the study. Eight treatment sessions lasting 40 minutes each (weekly) were performed. Assessments were conducted at baseline, immediately after treatment end, and 2 months later. Measurements included pain intensity at the temporomandibular joint, headache, cervicalgia, teeth clenching, ear symptoms, restricted sleep, and difficulties for mastication, using a visual analogue scale. In addition, electromyographic activity and pain thresholds were measured at the masseter, anterior temporalis, stemocleidomastoid, and upper trapezius muscles. Two-way analysis of variance with Tukey post hoc test was used for between-group comparisons. Significance level was .05. Results: Comparing the pain assessments using the visual analogue scale, no significant differences were seen with the exception of severity of headaches at treatment end (GPR, 3.92 +/- 2.98 cm; SS, 1.64 +/- 1.66 cm; P < .024). In addition, no significant differences were seen for pain thresholds and for electromyographic activity (P > .05). Conclusions: For the subjects in this study, both GPR and SS were similarly effective for the treatment of TMDs with muscular component. They equally reduced pain intensity, increased pain thresholds, and decreased electromyographic activity. (J Manipulative Physiol Ther 2010;33:500-507)

Calcitonin, sodium alendronate and high intensity laser in the treatment of traumatized teeth: a preliminary study

The aim of this study was to evaluate the influence of erbium:yttrium-aluminum-garnet (Er:YAG) laser compared with traditional treatment on dentin permeability to calcitonin and sodium alendronate. Forty bovine roots were sectioned and divided into eight groups. Groups 1 and 2 (G1/G2) were immersed in saline solution; G1T/G2T were immersed in ethylene diamine tetra-acetic acid plus sodium lauryl ether sulfate (EDTA-T) and sodium hypochlorite (NaOCl); G1I/G2I were irradiated with Er:YAG laser (2.94 mu m, 6 Hz, 40.4 J/cm(2)); G1TI/G2TI were immersed in EDTA-T, NaOCl and subjected to Er:YAG irradiation. After 4 h the radioactivity of the saline solution was measured. Statistical analysis revealed a significant difference (P < 0.05) when the groups treated with EDTA-T and NaOCl followed by Er:YAG laser irradiation were compared with the groups treated with EDTA-T only and with the groups that received no treatment. Er:YAG laser associated with traditional procedures significantly increased the diffusion of calcitonin and sodium alendronate through dentin. All groups showed calcitonin and sodium alendronate diffusion.

Squamous Cell Carcinoma of the Tongue and Floor of the Mouth: Analysis of Survival Rate and Independent Prognostic Factors in the Amazon Region

Oral squamous cell carcinoma (OSCC) accounts for more than 95% of all malignant neoplasms in the oral cavity. Although several studies have shown the epidemiology of this cancer in Brazil, there do not seem to be any studies that describe the prognostic factors related to OSCC in the Amazon region. Therefore, the aim of this study was to determine the survival rate and prognostic significance of different factors in patients from this region affected by OSCC. Data from 85 patients with histologically confirmed squamous cell carcinoma of the tongue and floor of the mouth identified from the Ofir Loyola Hospital archives were collected and analyzed using univariate (log-rank test) and multivariate (Cox proportional hazard model) tests. The overall 5-year survival rate was found to be 27%. Univariate analysis showed that the 5-year survival rate was significantly higher for younger (<= 45 y) female patients, patients with T1-2 tumors and clinically clear neck nodes (N0), patients with early stage cancers (AJCC stage I-II), and patients treated with surgical procedures. However, multivariate analysis showed that the 5-year survival rate was significantly higher only in the younger patients and those who underwent surgical treatment. The age of the patient at the moment of diagnosis and treatment with surgical procedures were the only independent prognostic factors that affected the 5-year survival rate of the patients in this region.

Effect of the C-factor and Dentin Preparation Method in the Bond Strength of a Mild Self-etch Adhesive

This study evaluated the effect of the C-factor and dentin preparation method (DPM) in the bond strength (BS) of a mild self-etch adhesive; the study also observed the SEM superficial aspects of the corresponding smear layer. For purposes of this study, 25 molars (n=5) were used in a bond strength test. The molars were divided into two parts (buccal and lingual): one part received a Class V cavity (C-factor=3) and the other received a flat surface (C-factor=0) with the same bur type (coarse diamond or carbide bur and fine diamond or carbide bur), both within the same dentin depth. Five teeth were prepared with wet 60-grit and 600-grit SiC papers. After restoration with Clearfil SE Bond, microtensile beans (0.8 mm(2)) were prepared and tested after 24 hours in a universal testing machine (0.5 mm/minute). An additional two teeth for each DPM were prepared for SEM evaluation of the smear layer superficial aspects. The BS values were submitted to one-way ANOVA, considering only the DPM (flat surfaces) and two-way ANOVA (C-Factor x DPM, considering only burs) with p=0.05. Although the DPM in the flat surfaces was not significant, the standard deviations of carbide bur-prepared specimens were markedly lower. The BS was significantly lower in cavities. The fine carbide bur presented the most favorable smear layer aspect. It was concluded that different dentin preparation methods could not prevent the adverse effect in bond strength of a high C-factor. A coarse cut carbide bur should be avoided prior to a mild self-etch adhesive, because it adversely affected bond strength. In contrast, a fine cut carbide bur provided the best combination: high bond strength with low variability, which suggests a more reliable bond strength performance.

Occlusal outcomes and efficiency of 1-and 2-phase protocols in the treatment of Class II Division 1 malocclusion

Introduction: The purpose of this study was to compare the occlusal outcomes and the efficiency of 1-phase and 2-phase treatment protocols in Class II Division 1 malocclusions. Treatment efficiency was defined as a change in the occlusal characteristics in a shorter treatment time. Methods: Class II Division 1 subjects ( n = 139) were divided into 2 groups according to the treatment protocol for Class II correction. Group 1 comprised 78 patients treated with a 1-phase treatment protocol at initial and final mean ages of 12.51 and 14.68 years. Group 2 comprised 61 patients treated with a 2-phase treatment protocol at initial and final mean ages of 11.21 and 14.70 years. Lateral cephalometric radiographs were taken at the pretreatment stage to evaluate morphological differences in the groups. The initial and final study models of the patients were evaluated by using the peer assessment rating index. Chi-square tests were used to test for differences between the 2 groups for categorical variables. Variables regarding occlusal results were compared by using independent t tests. A linear regression analysis was completed, with total treatment time as the dependent variable, to identify clinical factors that predict treatment length for patients with Class II malocclusions. Results: Similar occlusal outcomes were obtained between the 1-phase and the 2-phase treatment protocols, but the duration of treatment was significantly shorter in the 1-phase treatment protocol group. Conclusions: Treatment of Class II Division 1 malocclusions is more efficient with the 1-phase than the 2-phase treatment protocol.

The evolution of controlled multitasked gene networks: The role of introns and other noncoding RNAs in the development of complex organisms

Eukaryotic phenotypic diversity arises from multitasking of a core proteome of limited size. Multitasking is routine in computers, as well as in other sophisticated information systems, and requires multiple inputs and outputs to control and integrate network activity. Higher eukaryotes have a mosaic gene structure with a dual output, mRNA (protein-coding) sequences and introns, which are released from the pre-mRNA by posttranscriptional processing. Introns have been enormously successful as a class of sequences and comprise up to 95% of the primary transcripts of protein-coding genes in mammals. In addition, many other transcripts (perhaps more than half) do not encode proteins at all, but appear both to be developmentally regulated and to have genetic function. We suggest that these RNAs (eRNAs) have evolved to function as endogenous network control molecules which enable direct gene-gene communication and multitasking of eukaryotic genomes. Analysis of a range of complex genetic phenomena in which RNA is involved or implicated, including co-suppression, transgene silencing, RNA interference, imprinting, methylation, and transvection, suggests that a higher-order regulatory system based on RNA signals operates in the higher eukaryotes and involves chromatin remodeling as well as other RNA-DNA, RNA-RNA, and RNA-protein interactions. The evolution of densely connected gene networks would be expected to result in a relatively stable core proteome due to the multiple reuse of components, implying,that cellular differentiation and phenotypic variation in the higher eukaryotes results primarily from variation in the control architecture. Thus, network integration and multitasking using trans-acting RNA molecules produced in parallel with protein-coding sequences may underpin both the evolution of developmentally sophisticated multicellular organisms and the rapid expansion of phenotypic complexity into uncontested environments such as those initiated in the Cambrian radiation and those seen after major extinction events.

Disposition of naproxen, naproxen acyl glucuronide and its rearrangement isomers in the isolated perfused rat liver

1. An isolated perfused rat liver (IPRL) preparation was used to investigate separately the disposition of the non-steroidal anti-inflammatory drug (NSAID) naproxen (NAP), its reactive acyl glucuronide metabolite (NAG) and a mixture of NAG rearrangement isomers (isoNAG), each at 30 mug NAP equivalents ml(-1) perfusate (n = 4 each group). 2. Following administration to the IPRL, NAP was eliminated slowly in a log-linear manner with an apparent elimination half-life (t(1/2)) of 13.4 +/-4.4 h. No metabolites were detected in perfusate, while NAG was the only metabolite present in bile in measurable amounts (3.9 +/-0.8%, of the dose). Following their administration to the IPRL, both NAG and isoNAG were rapidly hydrolysed (t(1/2) in perfusate=57 +/-3 and 75 +/- 14min respectively). NAG also rearranged to isoNAG in the perfusate. Both NAG and isoNAG were excreted intact in bile (24.6 and 14.8% of the NAG and isoNAG doses, respectively). 3. Covalent NAP-protein adducts in the liver increased as the dose changed from NAP to NAG to isoNAG (0.20 to 0.34 to 0.48% of the doses, respectively). Similarly, formation of covalent NAP-protein adducts in perfusate were greater in isoNAG-dosed perfusions. The comparative results Suggest that isoNAG is a better substrate for adduct formation with liver proteins than NAG.

Liveweight gains of steers at different stocking rates on monospecific Gatton panic and Estrella grass pastures in the Chaco Central region of Paraguay

A grazing trial to study the effect of stocking rate on animal production and botanical composition of Gallon panic (Panicum maximum) and Estrella grass (Cynodon nlemfuensis) was conducted in the central region of the Paraguayan Chaco between 1992 and 1998. The experiment included 6 stocking rates (0.5, 0.8. 1.1, 1.4. 1.7 and 2.0 AU/ha) on individual 4-ha paddocks. The pasture treatments were continuously grazed by yearling steers. replaced annually, over a 4-year grazing period. No fertiliser was used. Botanical composition was recorded annually in autumn from 1992 to 1998 while animal production data were recorded monthly from 1992 to 1996. Relationships between animal productivity and stocking rates were determined by regression analysis. Gallon panic produced greater liveweight gains per head than Estrella grass at low and intermediate stocking rates. However, the slope of the linear relationship between liveweight gain per head and stocking rate increased each year in Gallon panic indicating that the productivity of this grass progressively declined at higher stocking rates over the period of observation. Estrella grass showed less sensitivity to stocking rate but was affected severely by periods of low rainfall.

Repeated blood pressure measurements in a sample of Swedish twins: heritabilities and associations with polymorphisms in the renin-angiotensin-aldosterone system Iliadou, Anastasia, Lichtenstein, Paul, Morgenstern, Ralf, Forsberg, Lena, Svensson, Richard, de Faire, Ulf, Martin, Nicholas, Pedersen, Nancy

Background Twin and family studies have shown that genetic effects explain a relatively high amount of the phenotypic variation in blood pressure. However, many studies have not been able to replicate findings of association between specific polymorphisms and diastolic and systolic blood pressure. Methods In a structural equation-modelling framework the authors investigated longitudinal changes in repeated measures of blood pressures in a sample of 298 like-sexed twin pairs from the population-based Swedish Twin Registry. Also examined was the association between blood pressure and polymorphisms in the angiotensin-I converting enzyme and the angiotensin 11 receptor type 1 with the 'Fulker' test Both linkage and association were tested simultaneously revealing whether the polymorphism is a Quantitative Trait Locus (QTL) or in linkage disequilibrium with the QTL. Results Genetic influences explained up to 46% of the phenotypic variance in diastolic and 63% of the phenotypic variance in systolic blood pressure. Genetic influences were stable over time and contributed up to 78% of the phenotypic correlation in both diastolic and systolic blood pressure. Non-shared environmental effects were characterised by time specific influences and little transmission from one time point to the next. There was no significant linkage and association between the polymorphisms and blood pressure. Conclusions There is a considerable genetic stability in both diastolic and systolic blood pressure for a 6-year period of time in adult life. Non-shared environmental influences have a small long-term effect Although associations with the polymorphisms could not be replicated, results should be interpreted with caution due to power considerations. (C) 2002 Lippincott Williams Wilkins.

An in situ study of photosynthetic oxygen exchange and electron transport rate in the marine macroalga Ulva lactuca (Chlorophyta)

Direct comparisons between photosynthetic O-2 evolution rate and electron transport rate (ETR) were made in situ over 24 h using the benthic macroalga Ulva lactuca (Chlorophyta), growing and measured at a depth of 1.8 m, where the midday irradiance rose to 400-600 mumol photons m(-2) s(-1). O-2 exchange was measured with a 5-chamber data-logging apparatus and ETR with a submersible pulse amplitude modulated (PAM) fluorometer (Diving-PAM). Steady-state quantum yield ((Fm'-Ft)/Fm') decreased from 0.7 during the morning to 0.45 at midday, followed by some recovery in the late afternoon. At low to medium irradiances (0-300 mumol photons m(-2) s(-1)), there was a significant correlation between O-2 evolution and ETR, but at higher irradiances, ETR continued to increase steadily, while O-2 evolution tended towards an asymptote. However at high irradiance levels (600-1200 mumol photons m-(2) s(-1)) ETR was significantly lowered. Two methods of measuring ETR, based on either diel ambient light levels and fluorescence yields or rapid light curves, gave similar results at low to moderate irradiance levels. Nutrient enrichment (increases in [NO3-], [NH4+] and [HPO42-] of 5- to 15-fold over ambient concentrations) resulted in an increase, within hours, in photosynthetic rates measured by both ETR and O-2 evolution techniques. At low irradiances, approximately 6.5 to 8.2 electrons passed through PS II during the evolution of one molecule of O-2, i.e., up to twice the theoretical minimum number of four. However, in nutrient-enriched treatments this ratio dropped to 5.1. The results indicate that PAM fluorescence can be used as a good indication of the photosynthetic rate only at low to medium irradiances.