Herpes viruses in periodontal compromised sites: comparison between HIV-positive and -negative patients

Aims: The objective of this study was to compare the frequency of herpes simplex virus type 1 (HSV-1), Epstein-Barr virus (EBV) and human cytomegalovirus (HCMV) in subgingival plaque, saliva and peripheral blood of HIV-positive and-negative patients with periodontal disease. Materials and Methods: Fifty HIV-positive subjects (23 with gingivitis, 27 with periodontitis) and 50 healthy HIV-negative patients with chronic periodontitis were included in the study. Parameters of probing depth (PD), clinical attachment level (CAL), gingival index and plaque index were recorded. The samples were processed for viral identification by the nested polymerase chain reaction technique. Results: HCMV was the most prevalent virus in HIV-positive (82%) and-negative patients (84%), and the detection in the three samples was similar (p > 0.05). HSV-1 was the least prevalent virus in both groups, being detected in similar frequencies in oral sites and in peripheral blood. EBV-1 was found more frequently in saliva and subgingival plaque of HIV-positive patients than in HIV-negative patients (p <= 0.05). Conclusions: EBV-1 was more frequently recovered in oral sites of HIV-positive patients than in HIV-negative patients.

Inflammatory Papillary Hyperplasia of the Palate: Quantitative Analysis of Candida albicans and its Negative Correlation with Microscopic and Demographic Aspects

Inflammatory papillary hyperplasia of the palate (IPHP) is a tissue-reactive overgrowth characterized by hyperemic mucosa with nodular or papillary appearance in the palate. The exact pathogenesis is still unclear. In this study, the presence of Candida albicans in the epithelial lining was evaluated using the indirect immunofluorescence staining technique. Strongly stained C albicans was observed only in the lesions of the IPHP group. Therefore, the detection of C albicans in almost all samples from IPHP tissue enabled a suggestion as to the microbial etiology of the disease, since the use of dental prostheses was reported. Int J Prosthodont 2011;24:235-237

Noradrenaline Involvement in the Negative-Feedback Effects of Ovarian Steroids on Luteinising Hormone Secretion

Noradrenaline has been shown to modulate the ovarian-steroid feedback on luteinising-hormone (LH) release. However, despite the high amount of evidence accumulated over many years, the role of noradrenaline in LH regulation is still not clearly understood. The present study aimed to further investigate the involvement of noradrenaline in the negative-feedback effect of oestradiol and progesterone on basal LH secretion. In experiment 1, ovariectomised (OVX) rats received a single injection of oil, oestradiol, or progesterone at 09.00-10.00 h and were decapitated 30 or 60 min later. Levels of noradrenaline and its metabolite, 3-methoxy-4-hydroxyphenylglycol (MHPG), were determined in microdissections of the preoptic area (POA) and medial basal hypothalamus-median eminence (MBH-ME) and correlated with LH secretion. Basal LH levels were decreased 30 and 60 min after oestradiol or progesterone injection, and this hormonal response was significantly correlated with a reduction in POA MHPG levels, which reflect noradrenaline release. In addition, noradrenaline levels in the POA were increased, whereas noradrenaline turnover (MHPG/noradrenaline ratio) was decreased 60 min after the injection of both hormones. No effect was found in the MBH-ME. In experiment 2, i.c.v. administration of noradrenaline (60 nmol), performed 15 min before oestradiol or progesterone injection in jugular vein-cannulated OVX rats, completely prevented the ovarian steroid-induced inhibition of LH secretion. The data obtained provide direct evidence that LH secretion in OVX rats is positively regulated by basal noradrenergic activity in the POA, and its reduction appears to play a role in the negative-feedback effect of ovarian steroids on LH secretion in vivo.

Revascularization and periapical repair after endodontic treatment using apical negative pressure irrigation versus conventional irrigation plus triantibiotic intracanal dressing in dogs` teeth with apical periodontitis

Objective. The objective of this study was to evaluate in vivo the revascularization and the apical and periapical repair after endodontic treatment using 2 techniques for root canal disinfection (apical negative pressure irrigation versus apical positive pressure irrigation plus triantibiotic intracanal dressing) in immature dogs` teeth with apical periodontitis. Study design. Two test groups of canals with experimentally induced apical periodontitis were evaluated according to the disinfection technique: Group 1, apical negative pressure irrigation (EndoVac system), and Group 2, apical positive pressure irrigation (conventional irrigation) plus triantibiotic intracanal dressing. In Group 3 (positive control), periapical lesions were induced, but no endodontic treatment was done. Group 4 (negative control) was composed of sound teeth. The animals were killed after 90 days and the maxillas and mandibles were subjected to histological processing. The sections were stained with hematoxylin and eosin and Mallory Trichrome and examined under light microscopy. A description of the apical and periapical features was done and scores were attributed to the following histopathological parameters: newly formed mineralized apical tissue, periapical inflammatory infiltrate, apical periodontal ligament thickness, dentin resorption, and bone tissue resorption. Intergroup comparisons were done by the Kruskal-Wallis and Dunn`s tests (alpha = 0.05). Results. Although statistically significant difference was found only for the inflammatory infiltrate (P < .05), Group 1 presented more exuberant mineralized formations, more structured apical and periapical connective tissue, and a more advanced repair process than Group 2. Conclusion. From the histological observations, sodium hypochlorite irrigation with the EndoVac system can be considered as a promising disinfection protocol in immature teeth with apical periodontitis, suggesting that the use of intracanal antibiotics might not be necessary. (Oral Surg Oral Med Oral Pathol Oral Radiol Endod 2010; 109: 779-787)

Apical negative pressure irrigation versus conventional irrigation plus triantibiotic intracanal dressing on root canal disinfection in dog teeth

Objective. The aim of this study was to compare in vivo the efficacy of 2 root canal disinfection techniques (apical negative pressure irrigation versus apical positive pressure irrigation plus triantibiotic intracanal dressing) in immature dog teeth with apical periodontitis. Study design. Two groups of root canals with pulp necrosis and apical periodontitis were evaluated according to the disinfection technique: group 1: apical negative pressure irrigation (EndoVac system); and group 2: apical positive pressure irrigation (conventional irrigation) plus triantibiotic intracanal dressing. The first sample (S1) was collected after lesions were radiographically visible, and the second sample (S2) was collected after apical negative pressure irrigation (group 1) or conventional irrigation/triantibiotic dressing (group 2). All samples were seeded in a culture medium for anaerobic bacteria. Colony-forming unit counts were analyzed statistically by the Mann-Whitney test (alpha = .05). Results. Microorganisms were present in 100% of canals of both groups in S1. In S2, microorganisms were absent in 88.6% of group 1`s canals and 78.28% of group 2`s canals. There was no significant difference between the groups in either S1 (P = .0963) or S2 (P = .0566). There was significant (P < .05) bacterial reduction from S1 to S2 in both groups. Conclusion. In immature teeth with apical periodontitis, use of the EndoVac system can be considered to be a promising disinfection protocol, because it provided similar bacterial reduction to that of apical positive pressure irrigation (conventional irrigation) plus intracanal dressing with the triantibiotic paste, and the use of intracanal antibiotics might not be necessary. (Oral Surg Oral Med Oral Pathol Oral Radiol Endod 2010;109:e42-e46)

Lineage-Negative Bone Marrow Cells Protect Against Chronic Renal Failure

Progressive renal failure continues to be a challenge. The use of bone marrow cells represents a means of meeting that challenge. We used lineage-negative (Lin(-)) cells to test the hypothesis that Lin(-) cell treatment decreases renal injury. Syngeneic Fischer 344 rats were divided into four groups: sham ( laparotomy only, untreated); Nx (five-sixth nephrectomy and untreated); NxLC1 (five-sixth nephrectomy and receiving 2 x 10(6) Lin(-) cells on postnephrectomy day 15); and NxLC3 (five-sixth nephrectomy and receiving 2 x 10(6) Lin(-) cells on postnephrectomy days 15, 30, and 45). On postoperative day 16, renal mRNA expression of interleukin (IL)-1 beta, tumor necrosis factor-alpha, and IL-6 was lower in NxLC rats than in Nx rats. On postnephrectomy day 60, NxLC rats presented less proteinuria, glomerulosclerosis, anemia, renal infiltration of immune cells, and protein expression of monocyte chemoattractant protein-1, as well as decreased interstitial area. Immunostaining for proliferating cell nuclear antigen showed that, in comparison with sham rats, Nx rats presented greater cell proliferation, whereas NxLC1 rats and NxLC3 rats presented less cell proliferation than did Nx rats. Protein expression of the cyclin-dependent kinase inhibitor p21 and of vascular endothelial growth factor increased after nephrectomy and decreased after Lin(-) cell treatment. On postnephrectomy day 120, renal function (inulin clearance) was significantly better in Lin(-) cell-treated rats than in untreated rats. Lin(-) cell treatment significantly improved survival. These data suggest that Lin(-) cell treatment protects against chronic renal failure. STEM CELLS 2009; 27: 682-692

Alternative mating tactics in dimorphic males of the harvestman Longiperna concolor (Arachnida: Opiliones)

Intense male-male competition for females may drive the evolution of male morphological dimorphism, which is frequently associated with alternative mating tactics. Using modern techniques for the detection of discontinuous allometries, we describe male dimorphism in the Neotropical harvestman Longiperna concolor, the males of which use their elongated, sexually dimorphic legs IV in fights for the possession of territories where females lay eggs. We also tested three predictions related to the existence of alternative mating tactics: (1) if individuals with relatively longer legs IV (majors) are more likely to monopolize access to reproductive resources, they are expected to remain close to stable groups of females more than individuals with relatively shorter legs IV (minors) do; (2) if minors achieve fertilization by moving between territories, they are expected to be less faithful to specific sites; and (3) majors should be observed in aggressive interactions more often. We individually marked all the individuals from a population of Longiperna during the reproductive season and recorded the location of each sighting for males and females as well as the identity of males involved in fights. Majors were more likely to have harems, and large majors were even more likely to do so. Majors were more philopatric and all males involved in fights belonged to this morph. These results strongly suggest that the mating tactic of the majors is based on resource defense whereas that of the minors probably relies on sneaking into the territories of the majors and furtively copulating with females.

Mating system and exclusive postzygotic paternal care in a Neotropical harvestman (Arachnida: Opiliones)

This study tests predictions of the hypothesis of evolution of paternal care via sexual selection by using the Neotropical harvestman Pseudopucrolia sp. as the model organism. Females use natural cavities in roadside banks as nesting sites, which are defended by males against other males. Females leave the nests after oviposition, and all postzygotic parental care is accomplished by males, which protect the eggs and nymphs from predators. We provided artificial mud nests to individuals in the laboratory and conducted observations on the reproduction of the species. Male reproductive success was directly related to nest ownership time: the longer a male held a nest, the higher his chances of obtaining copulations. All males that succeeded in mating and obtaining one clutch eventually mated with additional females that added eggs to the clutch. Thus, desirable males were not limited to monogamy by paternal care. Experimental manipulations demonstrated that guarding males were more attractive to females than were nonguarding males and also that males guarded unrelated eggs. Finally, we found that females and nonguarding males spent more time foraging than guarding males. We use our data to contrast hypotheses on the origin and maintenance of paternal care and to provide a critical assessment of the hypothesis of the evolution of paternal care via sexual selection. (C) 2009 The Association for the Study of Animal Behaviour. Published by Elsevier Ltd. All rights reserved.

Negative anticipatory contrast: Does it involve anticipation of an impending reward?

Negative anticipatory contrast (NAC) corresponds to the suppression in consumption of a first rewarding substance (e.g., saccharin 0.15%) when it is followed daily by a second preferred substance (e.g., sucrose 32%). The NAC has been interpreted as resulting from anticipation of the impending preferred reward and its comparison with the currently available first reward [Flaherty, CF., Rowan, G.A., 1985. Anticipatory contrast: within-subjects analysis. Anim. Learn. Behav. 13, 2-5]. In this context, one should expect that devaluation of the preferred substance after the establishment of the NAC would either reduce or abolish the contrast effect. However, contrary to this prediction, the results of the present study show that the NAC is insensitive to devaluation of the second, preferred, substance. This allows one to question that interpretation. The results reported in this study support the view that the NAC effect is controlled by memory of the relative value of the first solution, which is updated daily by means of both a gustatory and/or post-ingestive comparison of the first and second solutions, and memory of past pairings. (C) 2010 Elsevier B.V. All rights reserved.

Mating behavior of Sickius longibulbi (Araneae, Theraphosidae, Ischnocolinae), a spider that lacks spermathecae

We describe the mating behavior in the spermatheca-lacking theraphosid species Sickius longibulbi Soares & Camargo 1948. The behavior in captivity of nine pairs of S. longibulbi was videotaped and analyzed. The matting of this species presented an uncommon theraphosid pattern. There is little in the way of overt courtship by the male, the primary behavior seen being the male`s use of legs I and II to touch the female`s first pairs of legs and her chelicerae. Sometimes the male clasped one of the female`s first pairs of legs, bringing her close to him. While the female raised her body, the male clasped her fangs and held her tightly with his legs III wrapped around her prosoma. The male seemed to try to knock the female down, pushing her entire body until she lay on her dorsum. In this phase we observed the male biting the female on the sternum or on the leg joints. When the female fell, the male attempted to position himself at an angle of 90 degrees from the female. These movements appear to demand a lot of energy, particularly because the female is not passive during the mating. Our findings suggest that copulating in this position is, for the male, more successful than adopting other positions because it allows his extremely long palpal bulbs to deposit more sperm in the female oviduct where - since she lacks spermathecae - she retains the sperm. We suggest that the further he reaches into the oviduct, the greater the chance that he will fertilize the female`s eggs.

Do individuals in better condition survive for longer? Field survival estimates according to male alternative reproductive tactics and sex

There is a gap in terms of the supposed survival differences recorded in the field according to individual condition. This is partly due to our inability to assess survival in the wild. Here we applied modern statistical techniques to field-gathered data in two damselfly species whose males practice alternative reproductive tactics (ARTs) and whose indicators of condition in both sexes are known. In Paraphlebia zoe, there are two ART: a larger black-winged (BW) male which defends mating territories and a smaller hyaline-winged (HW) male that usually acts as a satellite. In this species, condition in both morphs is correlated with body size. In Calopteryx haemorrhoidalis, males follow tactics according to their condition with males in better condition practicing a territorial ART. In addition, in this species, condition correlates positively with wing pigmentation in both sexes. Our prediction for both species was that males practicing the territorial tactic will survive less longer than males using a nonterritorial tactic, and larger or more pigmented animals will survive for longer. In P. zoe, BW males survived less than females but did not differ from HW males, and not necessarily larger individuals survived for longer. In fact, size affected survival but only when group identity was analysed, showing a positive relationship in females and a slightly negative relationship in both male morphs. For C. haemorrhoidalis, survival was larger for more pigmented males and females, but size was not a good survival predictor. Our results partially confirm assumptions based on the maintenance of ARTs. Our results also indicate that female pigmentation, correlates with a fitness component - survival - as proposed by recent sexual selection ideas applied to females.

Arachidonic acid actions on functional integrity and attenuation of the negative effects of palmitic acid in a clonal pancreatic beta-cell line

Chronic exposure of pancreatic beta-cells to saturated non-esterified fatty acids can lead to inhibition of insulin secretion and apoptosis. Several previous studies have demonstrated that saturated fatty acids such as PA (palmitic acid) are detrimental to beta-cell function compared with unsaturated fatty acids. In the present study, we describe the effect of the polyunsaturated AA (arachidonic acid) on the function of the clonal pancreatic beta-cell line BRIN-BD11 and demonstrate AA-dependent attenuation of PA effects. When added to beta-cell incubations at 100 mu M, AA can stimulate cell proliferation and chronic (24 h) basal insulin secretion. Microarray analysis and/or real-time PCR indicated significant AA-dependent up-regulation of genes involved in proliferation and fatty acid metabolism [e.g. Angptl (angiopoietin-like protein 4), Ech1 (peroxisomal Delta(3.5),Delta(2.4)-dienoyl-CoA isomerase), Cox-1 (cyclo-oxygenase-1) and Cox-2, P < 0.05]. Experiments using specific COX and LOX (lipoxygenase) inhibitors demonstrated the importance of COX-1 activity for acute (20 min) stimulation of insulin secretion, suggesting that AA metabolites may be responsible for the insulinotropic effects. Moreover, concomitant incubation of AA with PA dose-dependently attenuated the detrimental effects of the saturated fatty acid, so reducing apoptosis and decreasing parameters of oxidative stress [ROS (reactive oxygen species) and NO levels] while improving the GSH/GSSG ratio. AA decreased the protein expression of iNOS (inducible NO synthase), the p65 subunit of NF-kappa B (nuclear factor kappa B) and the p47 subunit of NADPH oxidase in PA-treated cells. These findings indicate that AA has an important regulatory and protective beta-cell action, which may be beneficial to function and survival in the `lipotoxic` environment commonly associated with Type 2 diabetes mellitus.

TLR2 Is a Negative Regulator of Th17 Cells and Tissue Pathology in a Pulmonary Model of Fungal Infection

To study the role of TLR2 in a experimental model of chronic pulmonary infection, TLR2-deficient and wild-type mice were intratracheally infected with Paracoccidioides brasiliensis, a primary fungal pathogen. Compared with control, TLR2(-/-) mice developed a less severe pulmonary infection and decreased NO synthesis. Equivalent results were detected with in vitro-infected macrophages. Unexpectedly, despite the differences in fungal loads both mouse strains showed equivalent survival times and severe pulmonary inflammatory reactions. Studies on lung-infiltrating leukocytes of TLR2(-/-) mice demonstrated an increased presence of polymorphonuclear neutrophils that control fungal loads but were associated with diminished numbers of activated CD4(+) and CD8(+) T lymphocytes. TLR2 deficiency leads to minor differences in the levels of pulmonary type 1 and type 2 cytokines, but results in increased production of KC, a CXC chemokine involved in neutrophils chemotaxis, as well as TGF-beta, IL-6, IL-23, and IL-17 skewing T cell immunity to a Th17 pattern. In addition, the preferential Th17 immunity of TLR2(-/-) mice was associated with impaired expansion of regulatory CD4(+)CD25(+)FoxP3(+) T cells. This is the first study to show that TLR2 activation controls innate and adaptive immunity to P. brasiliensis infection. TLR2 deficiency results in increased Th17 immunity associated with diminished expansion of regulatory T cells and increased lung pathology due to unrestrained inflammatory reactions. The Journal of Immunology, 2009, 183: 1279-1290.

A Metal-Repressed Promoter From Gram-Positive Bacillus subtilis Is Highly Active and Metal-Induced in Gram-Negative Cupriavidus metallidurans

A synthetic version of the metal-regulated gene A (mrgA) promoter from Bacillus subtilis, which in this Gram-positive bacterium is negatively regulated by manganese, iron, cobalt, or copper turned out to promote high level of basal gene expression that is further enhanced by Co(II), Cd(II), Mn(II), Zn(II), Cu(II), or Ni(II), when cloned in the Gram-negative bacterium Cupriavidus metallidurans. Promoter activity was monitored by expression of the reporter gene coding for the enhanced green fluorescent protein (EGFP), and cellular intensity fluorescence was quantified by flow cytometry. Expression levels in C. metallidurans driven by the heterologous promoter, here called pan, ranged from 20- to 53-fold the expression level driven by the Escherichia coli lac promoter (which is constitutively expressed in C. metallidurans), whether in the absence or presence of metal ions, respectively. The pan promoter did also function in E. coli in a constitutive pattern, regardless of the presence of Mn(II) or Fe(II). In conclusion, the pan promoter proved to be a powerful tool to express heterologous proteins in Gram-negative bacteria, especially in C. metallidurans grown upon high levels of toxic metals, with potential applications in bioremediation. Biotechnol. Bioeng. 2010; 107: 469-477. (C) 2010 Wiley Periodicals, Inc.

The effect of the negative coupling parameter on the spectrum of a trapped Bose gas

The interest in attractive Bose-Einstein Condensates arises due to the chemical instabilities generate when the number of trapped atoms is above a critical number. In this case, recombination process promotes the collapse of the cloud. This behavior is normally geometry dependent. Within the context of the mean field approximation, the system is described by the Gross-Pitaevskii equation. We have considered the attractive Bose-Einstein condensate, confined in a nonspherical trap, investigating numerically and analytically the solutions, using controlled perturbation and self-similar approximation methods. This approximation is valid in all interval of the negative coupling parameter allowing interpolation between weak-coupling and strong-coupling limits. When using the self-similar approximation methods, accurate analytical formulas were derived. These obtained expressions are discussed for several different traps and may contribute to the understanding of experimental observations.