Stimulation by thyrotropin, long-acting thyroid stimulator, and dibutyryl 3′, 5′-adenosine monophosphate of protein and ribonucleic acid synthesis and ribonucleic acid polymerase activities in porcine thyroid in Vitro

The in vitro incorporation of [3H]uridine into RNA and [3H]leucine into protein in slices of porcine thyroid was studied. Thyrotropin (10-500 mU/ml of medium), when added with [3H]uridine, inhibited incorporation into RNA, but as little as 10 mU of thyrotropin per ml stimulated incorporation of [3H]orotic acid into RNA. Uridine kinase (EC 2.7.1.48) was found to be inhibited in slices incubated with thyrotropin whereas UMP 5′ nucleotidase (EC 2.1.3.5) was not. Preincubation of slices with thyrotropin (5-50 mU/ml) led to enhanced incorporation of subsequently added [3H]uridine and [3H]leucine. When slices were preincubated with long-acting thyroid stimulator-IgG (2.5 or 5 mg per ml of medium) incorporation of [3H]uridine and [3H]leucine was similarly enhanced, with the smaller concentration being more effective. Without preincubation these stimulatory effects were mimicked by 1 mM dibutyryl 3′,5′-AMP and, to a lesser extent, 1 mM 3′,5′-AMP. AMP and ATP also stimulated [3H]uridine incorporation in this system but only after more prolonged periods of incubation than were required for the other nucleotides. RNA polymerase (EC 2.7.7.6) activity measured in isolated thyroid nuclei had two components, one Mg2+-stimulated and the other requ ring Mn2+ and high salt content [0.4 M (NH4)2SO4]. These activities, and particularly the former, were enhanced if thyroid slices were incubated with thyrotropin (5-100 mU/ml of medium), 2.5 mg or 5.0 mg of long-acting thyroid stimulator-IgG per ml, or 1 mM dibutyryl 3′,5′-AMP, before isolatior of the nuclei and measurement of enzyme activities; 1 mM AMP, ADP, or 2′,3′-GMP had no influence. Added directly to the nuclei, thyrotropin, long-acting thyroid stimulator-IgG, and dibutyryl 3′,5′-AMP had no effect on RNA polymerase activities. These data are seen as affording evidence for mediation by 3′,5′-AMP of effects of thyrotropin and long-acting thyroid stimulator on thyroid RNA and protein synthesis, at least in part through an indirect stimulation of nuclear RNA polymerase activities.

Cicatrização de anastomose colônica reforçada por esponja de colágeno revestida com fatores de coagulação (TachoSil) em ratos submetidos à quimioterapia intraperitoneal perioperatória precoce com 5-fluorouracil

A administração intraperitoneal de 5-fluorouracil (5-FU) no pós-operatório imediato reduz a recorrência local e prolonga a sobrevida dos pacientes com câncer colônico. Contudo, esse tratamento também pode prejudicar a cicatrização das anastomoses intestinais. O objetivo deste estudo foi determinar os efeitos da quimioterapia (QT) intraperitoneal (IP) pós-operatória (PO) precoce com o 5-FU e da selagem anastomótica com o TachoSil sobre o processo de cicatrização de anastomoses colônicas. Quarenta ratos foram divididos em quatro grupos (I - IV, com dez ratos em cada) e submetidos à secção do cólon esquerdo seguida por anastomose. As anastomoses dos ratos dos grupos II e IV foram cobertas com o TachoSil. Solução salina (2 ml/dia grupos I e II) ou 5-FU (20 mg/kg/dia grupos III e IV) foi administrado por via IP uma vez ao dia, desde do procedimento cirúrgico até a morte programada dos animais no quarto dia pós-operatório. Foram realizadas medidas da pressão de ruptura e análise histopatológica das anastomoses. A perda relativa de peso foi significativamente maior nos animais do grupo III comparado a todos os demais grupos (p=0,0004). Não houve diferença significativa entre os grupos no que se refere à presença de fístulas, coleções perianastomóticas, sinais de dilatação intestinal pré-anastomótica ou aderências pós-operatórias. A pressão de ruptura foi significativamente menor no grupo III comparada a todos os demais grupos (p=0,001). A neoangiogênese foi significativamente menor no grupo III comparada aos grupos I e II (p=0,05). A infiltração fibroblástica foi significativamente maior no grupo I e em comparação ao grupo III (p=0,035). Não ocorreu diferença significativa entre os grupos no que concerne à presença de infiltração de células inflamatórias e deposição de colágeno. Os dados obtidos permitem concluir que a QT IP precoce com 5-FU afetou negativamente a fase inicial da cicatrização de anastomoses colônicas. Contudo, a selagem com o TachoSil foi capaz de reverter alguns dos efeitos adversos decorrentes da QT.

Physicochemical properties of silk fibroin after solubilization using calcium chloride with or without ethanol

To elucidate the physicochemical properties of silk protein, we studied the effects of calcium chloride and ethanol on the gelation of fibroin. Fibroin was treated with 5.0 M calcium chloride in water (Ca/W) or 5.0 M calcium chloride in 20% (v/v) ethanol (Ca/Et) and the rheological properties of colloidal fibroin were investigated. The Ca/W-treatment promoted an increased rate of gelation and gave higher gel strength than the Ca/Et-treatment. The maximum gel strengths of Ca/W- and Ca/Et-treated fibroins were obtained at pH 7.0 and pH 5.5, respectively. Scanning electron micrographs showed that the Ca/W-treated fibroin gel had a more developed three-dimensional molecular network than the Ca/Et-treated gel. Further, FT-IR spectra suggested that Ca/W-treated fibroin has more of a beta-structure than Ca/Et-treated one in colloidal conditions. This study indicated that the use of calcium chloride alone was more beneficial to the gelation of fibroin than combined use with ethanol.

The shunt from the cyclooxygenase to lipoxygenase pathway in human osteoarthritic subchondral osteoblasts is linked with a variable expression of the 5-lipoxygenase-activating protein

Affiliation: Unité de recherche en Arthrose, Centre de recherche du Centre Hospitalier de l'Université de Montréal, Hôpital Notre-Dame

Elevated atmospheric CO2 and humidity delay leaf fall in Betula pendula, but not in Alnus glutinosa or Populus tremula × tremuloides

Context: Anthropogenic activity has increased the level of atmospheric CO2, which is driving an increase of global temperatures and associated changes in precipitation patterns. At Northern latitudes, one of the likely consequences of global warming is increased precipitation and air humidity. Aims: In this work, the effects of both elevated atmospheric CO2 and increased air humidity on trees commonly growing in northern European forests were assessed. Methods: The work was carried out under field conditions by using Free Air Carbon dioxide Enrichment (FACE) and Free Air Humidity Manipulation (FAHM) systems. Leaf litter fall was measured over 4 years (FACE) or 5 years (FAHM) to determine the effects of FACE and FAHM on leaf phenology. Results: Increasing air humidity delayed leaf litter fall in Betula pendula, but not in Populus tremula × tremuloides. Similarly, under elevated atmospheric CO2, leaf litter fall was delayed in Betula pendula, but not in Alnus glutinosa. Increased CO2 appeared to interact with periods of low precipitation in summer and high ozone levels during these periods to effect leaf fall. Conclusions: This work shows that increased CO2 and humidity delay leaf fall, but this effect is species specific.

Epidural analgesia with morphine or buprenorphine in ponies with lipopolysaccharide (LPS)-induced carpal synovitis

This study evaluated the analgesia effects of the epidural administration of 0.1 mg/kg bodyweight (BW) of morphine or 5 mu g/kg BW of buprenorphine in ponies with radiocarpal joint synovitis. Six ponies were submitted to 3 epidural treatments: the control group (C) received 0.15 mL/kg BW of a 0.9% sodium chloride (NaCl) solution; group M was administered 0.1 mg/kg BW of morphine; and group B was administered 5 mu g/kg BW of buprenorphine, both diluted in 0.9% NaCl to a total volume of 0.15 mL/kg BW administered epidurally at 10 s/mL. The synovitis model was induced by injecting 0.5 ng of lipopolysaccharide (LPS) in the left or right radiocarpal joint. An epidural catheter was later introduced in the lumbosacral space and advanced up to the thoracolumbar level. The treatment started 6 h after synovitis induction. Lameness, maximum angle of carpal flexion, heart rate, systolic arterial pressure, respiratory rate, temperature, and intestinal motility were evaluated before LPS injection (baseline), 6 h after LPS injection (time 0), and 0.5, 1, 2, 4, 6, 8, 10, 12, 16, 20, and 24 h after treatments. Although the model of synovitis produced clear clinical signs of inflammation, the lameness scores in group C were different from the baseline for only up to 12 h. Both morphine and buprenorphine showed a reduction in the degree of lameness starting at 0.5 and 6 h, respectively. Reduced intestinal motility was observed at 0.5 h in group M and at 0.5 to 1 h in group B. Epidural morphine was a more effective analgesic that lasted for more than 12 h and without side effects. It was concluded that morphine would be a valuable analgesic option to alleviate joint pain in the thoracic limbs in ponies.

Blockade of 5-HT2 receptors in the periaqueductal grey matter (PAG) abolishes the anxiolytic-like effect of 5-HT1A receptor antagonism in the median raphe nucleus in mice

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

5-HT2 receptor activation in the midbrain periaqueductal grey (PAG) reduces anxiety-like behaviour in mice

It is widely acknowledged that the indoleamine neurotransmitter serotonin (5-HT) plays a dual role in the regulation of anxiety, a role that in part depends upon neuroanatomical locus of action. Thus, whereas stimulation of 5-HT1A or 5-HT2 receptors in the limbic forebrain (amygdala, hippocampus) enhances anxiety-like responding in rodents, activation of corresponding receptor populations in the midbrain periaqueductal grey (PAG) more often than not reduce anxiety-like behaviour. The present study specifically concerns the anxiety-modulating influence of 5-HT2 receptors within the mouse PAG. Experiment 1 assessed the effects of intra-PAG infusions of the 5-HT2B/2C receptor agonist mCPP (0, 0.03, 0.1 or 0.3 nmol/0.1 mu l) on the behaviour of mice exposed to the elevated plus-maze. As mCPP acts preferentially at 5-HT2B and 5-HT2C receptors, Experiment 2 investigated its effects in animals pretreated with ketanserin, a preferential 5-HT2A/2C receptor antagonist. In both cases, test sessions were videotaped and subsequently, scored for anxiety-like behaviour (e.g., percentage of open arm entries and percentage of open arm time) as well as general locomotor activity (closed arm entries). The results of Experiment I showed that mCPP microinfusions (0.03 and 0.1 nmol) into the PAG of mice decreased behavioural indices of anxiety without significantly altering general activity measures. In Experiment 2, the anxiolytic-like profile of intra-PAG mCPP (0.03 nmol) was substantially attenuated by intra-PAG pretreatment with an intrinsically inactive dose of the preferential 5-HT2A/2C receptor antagonist, ketanserin (10 nmol/0.1 mu l). Together, these data suggest that 5HT(2C) receptor populations within the midbrain PAG play an inhibitory role in plus-maze anxiety in mice. (C) 2007 Elsevier B.V. All rights reserved.

5-HT1A, but not 5-HT2 and 5-HT7, receptors in the nucleus raphe magnus modulate hypoxia-induced hyperpnoea

Aim: In the present study, we assessed the role of 5-hydroxytryptamine (5-HT) receptors (5-HT1A, 5-HT2 and 5-HT7) in the nucleus raphe magnus (NRM) on the ventilatory and thermoregulatory responses to hypoxia.Methods: To this end, pulmonary ventilation (V-E) and body temperature (T-b) of male Wistar rats were measured in conscious rats, before and after a 0.1 mu L microinjection of WAY-100635 (5-HT1A receptor antagonist, 3 mu g 0.1 mu L-1, 56 mM), ketanserin (5-HT2 receptor antagonist, 2 mu g 0.1 mu L-1, 36 mM) and SB269970 (5-HT7 receptor antagonist, 4 mu g 0.1 mu L-1, 103 mM) into the NRM, followed by 60 min of severe hypoxia exposure (7% O-2).Results: Intra-NMR microinjection of vehicle (control rats) or 5-HT antagonists did not affect V-E or T-b during normoxic conditions. Exposure of rats to 7% O-2 evoked a typical hypoxia-induced anapyrexia after vehicle microinjections, which was not affected by microinjection of WAY-100635, SB269970 or ketanserin. The hypoxia-induced hyperpnoea was not affected by SB269970 and ketanserin intra-NMR. However, the treatment with WAY-100635 intra-NRM attenuated the hypoxia-induced hyperpnoea.Conclusion: These data suggest that 5-HT acting on 5-HT1A receptors in the NRM increases the hypoxic ventilatory response.

Comparative study of epidural xylazine or clonidine in horses

Objective To evaluate the cardiorespiratory and behavioural effects of epidural xylazine (XYL) or clonidine (CLO) in horses.Study design Blinded, randomized experimental study.Twelve healthy Arabian yearling horses weighing 117-204 kg were randomly allocated into two groups: XYL (n = 6) and CLO (n = 6).Methods An epidural catheter was inserted and a facial arterial catheter was placed and the next day the horses were restrained in stocks. Baseline values for heart (HR) and respiratory (RR) rates, arterial pressure and behavioural responses were evaluated before (TO) and 10, 20, 30, 45, 60, 90 and 120 minutes after epidural injection (T10-T120). The horses received 0.2 mg kg(-1) of XYL or 5 mu g kg(-1) CLO; adjusted to (3.4 + (body weight in kg x 0.013) mL with saline. Data were analysed by the Kolmogorov-Smirnov test, one-way ANOVA with repeated measures, and one-way ANOVA followed by a Student-Newman-Keuls test or Fisher's exact test, as necessary. Significance was set at p <= 0.05.Results Sedation and ataxia were seen at T10, persisting until T120 in four and three horses, respectively, in XYL and all horses in CLO respectively. Two XYL and one CLO horses became recumbent at T45 and T25 respectively. Penile prolapse occurred in four of five males at T30 and T45, in the XYL and CLO groups, respectively, resolving by T120. Tail relaxation was present from T10 to T120 in all horses in XYL and in four horses in CLO. Head drop was observed from T20 to T60 and from T10 to T120 in XYL and CLO respectively. Respiratory rate decreased significantly only at T45 in the CLO group. Heart rate and arterial blood pressure remained stable.Conclusions and clinical relevance Epidural CLO and XYL produce similar cardiorespiratory and behavioural changes but neither would be safe to use clinically at the doses used in this study.

Análise comparativa entre terapia fotodinâmica com ácido 5-aminolevulínico versus crioterapia no tratamento da queratose actínica: estudo prospectivo randonizado

Pós-graduação em Pesquisa e Desenvolvimento (Biotecnologia Médica) - FMB

Efeito in vitro e in vivo do 5-hidroxi-2-hidroximetil-gama-pirona durante a infecção por Leishmania (Leishmania) amazonensis

As leishmanioses são um grupo de doenças infecciosas distribuídas mundialmente. A quimioterapia é o tratamento mais eficaz para a doença; apesar do grande número de drogas antileishmania disponíveis, são usualmente tóxicas, caras e requerem um longo período de tratamento. Portanto, torna-se necessária a busca de novas substâncias que sejam capazes de atuar sobre o protozoário sem causar danos ao hospedeiro, que tenham uma via de administração não invasiva e que, ainda, sejam viáveis economicamente. O ácido kójico, ou 5-hidroxi-2-hidroximetil-γ-pirona (HMP), é conhecido por inibir a enzima tirosinase no processo de produção da melanina, sendo extensivamente utilizado em cosméticos e também como tratamento tópico para melasma, não havendo citotoxicidade em humanos; entretanto, o potencial do HMP como agente antileishmania não é conhecido. O presente estudo analisou o efeito deste bioproduto em infecções por L. amazonensis in vitro e in vivo. O HMP promoveu a diminuição do crescimento de promastigotas e amastigotas em 62% (IC₅₀ 34μg/mL) e 79% (IC₅₀ 27,84 μg/mL) in vitro, respectivamente. A análise ultraestrutural de ambas as formas evolutivas tratadas com 50 μg/mL do HMP apresentaram corpos vesiculares no interior da bolsa flagelar, induziu uma intensa vacuolização intracelular bem como alterações mitocondriais. O estudo in vitro também demonstrou que o HMP foi capaz de reverter o efeito inibitório causado pela L. amazonensis no que diz respeito à produção de radicais de oxigênio. A análise histopatológica de lesões proveniente de animais submetidos ao tratamento tópico com o HMP demonstrou que o tecido apresentou um intenso processo de cicatrização. Além disso, fibras colágenas foram encontradas de maneira organizada no local da infecção de animais tratados, com um pequeno infiltrado celular e diminuição do número de parasitos. Tendo em vista a ação seletiva do HMP in vitro, o processo de ativação da célula hospedeira pelo bioproduto e a diminuição do número de parasitos observados durante o tratamento com a pomada, e pelo fato do HMP ser amplamente utilizado como agente antimelasma em humanos, esse metabólito pode ser promissor como tratamento tópico contra a Leishmaniose cutânea e apresentando grande potencial como agente leishmanicida.

mu(1)- and 5-HT1-dependent mechanisms in the anterior pretectal nucleus mediate the antinociceptive effects of retrosplenial cortex stimulation in rats

Aim: This study examines if injection of cobalt chloride (CoCl2) or antagonists of muscarinic cholinergic (atropine), mu(1)-opioid (naloxonazine) or 5-HT1 serotonergic (methiothepin) receptors into the dorsal or ventral portions of the anterior pretectal nucleus (APtN) alters the antinociceptive effects of stimulating the retrosplenial cortex (RSC) in rats. Main method: Changes in the nociceptive threshold were evaluated using the tail flick or incision pain tests in rats that were electrically stimulated at the RSC after the injection of saline, CoCl2 (1 mM, 0.10 mu L) or antagonists into the dorsal or ventral APtN. Key findings: The injection of CoCl2, naloxonazine (5 mu g/0.10 mu L) or methiothepin (3 mu g/0.10 mu L) into the dorsal APtN reduced the stimulation-produced antinociception from the RSC in the rat tail flick test. Reduction of incision pain was observed following stimulation of the RSC after the injection of the same substances into the ventral APtN. The injection of atropine (10 ng/0.10 mu L) or ketanserine (5 mu g/0.10 mu L) into the dorsal or ventral APtN was ineffective against the antinociception resulting from RSC stimulation. Significance: mu(1)-opioid- and 5-HT1-expressing neurons and cell processes in dorsal and ventral APtN are both implicated in the mediation of stimulation-produced antinociception from the RSC in the rat tail flick and incision pain tests, respectively. (c) 2012 Elsevier Inc. All rights reserved.

Biocompatibility and setting time of CPM-MTA and white Portland cement clinker with or without calcium sulfate

To evaluate the biocompatibility and the setting time of Portland cement clinker with or without 2% or 5% calcium sulfate and MTA-CPM. Twenty-four mice (Rattus norvegicus) received subcutaneously polyethylene tubes filled with Portland cement clinker with or without 2% or 5% calcium sulfate and MTA. After 15, 30 and 60 days of implantation, the animals were killed and specimens were prepared for microscopic analysis. For evaluation of the setting time, each material was analyzed using Gilmore needles weighing 113.5 g and 456.5 g, according to the ASTM specification Number C266-08 guideline. Data were analyzed by ANOVA and Tukey's test for setting time and Kruskal-Wallis and Dunn test for biocompatibility at 5% significance level. Histologic observation showed no statistically significant difference of biocompatibility (p>0.05) among the materials in the subcutaneous tissues. For the setting time, clinker without calcium sulfate showed the shortest initial and final setting times (6.18 s/21.48 s), followed by clinker with 2% calcium sulfate (9.22 s/25.33 s), clinker with 5% calcium sulfate (10.06 s/42.46 s) and MTA (15.01 s/42.46 s). All the tested materials showed biocompatibility and the calcium sulfate absence shortened the initial and final setting times of the white Portland cement clinker

Clinical and microbiological analysis of subjects treated with Brånemark or AstraTech implants: a 7-year follow-up study

AIMS: To assess the impact of different implant systems on the clinical conditions and the microbiota at implants, and whether the presence of bacteria at tooth sites was predictive of the presence at implant sites. MATERIALS AND METHODS: Subjects with either AstraTech or Brånemark in function for 7 years were enrolled. Sub-gingival bacterial samples at tooth and implant sites were collected with sterile endodontic paper points, and analyzed by the checkerboard DNA-DNA hybridization method (40 species). RESULTS: Fifty-four subjects, 27 supplied with AstraTech (n=132 implants) and 27 with Brånemark (n=102) implants, were studied. Test tooth sites had significantly less evidence of bleeding on probing (P<0.001) and presence of plaque (P<0.001) than implant test sites. Implant sites presented with deeper probing pocket depth than tooth sites (mean difference: 1.1 mm, standard error of differences: 0.08, 95% confidence intervals (CI): 0.9-1.3, P<0.001). Tannerella forsythia (P<0.05), Capnocytophaga sputigena (P<0.05), Actinomyces israelii (P<0.05) and Lactobacillus acidophilus (P<0.05) were found at higher levels at tooth surfaces. No differences in bacterial load for any species were found between the two implant systems. The odds of being present/absent at tooth and implants sites were only significant for Staphylococcus aureus [odds ratio (OR): 5.2 : 1, 95% CI: 1.4-18.9, P<0.01]. CONCLUSIONS: After 7 years in function, implants presented with deeper probing depths than teeth. S. aureus was commonly present at both teeth and implants sites. S. aureus at tooth sites was predictive of also being present at implant sites.