Stomatological disorders in older people: An epidemiological study in the Brazil southern.

BACKGROUND: The aim of this retrospective, cross-sectional and observational study was to perform a survey of the stomatological conditions of elderly patients seen in a period of 40 years at a Stomatology Service in Southern Brazil. MATERIAL AND METHODS: A total of 24,347 medical records were reviewed, of which 5,063 belonged to elderly patients aged 60 to 97 years. The stomatological conditions, systemic conditions, and smoking and alcohol drinking habits as well were recorded. RESULTS: The mean age of the patients was 69.29 years, 67.1% were female and 32.9% were male. Variations of normality accounted for 44.5% of the cases. The most prevalent disorders were fungal infections (26.1%), reactive inflammatory lesions (24.6%), burning mouth syndrome (14.9%), benign neoplasms (12.4%), autoimmune disorders (12.3%), premalignant lesions (10.2%) and malignant epithelial neoplasms (7.2%). Regarding biopsied lesions, squamous cell carcinoma was the most prevalent at 30.2%, followed by hyperplasic lesions (28.2%). CONCLUSIONS: Knowledge of these physiological and pathological conditions in the oral cavity of the older people is essential for early diagnosis and preventive and therapeutic measures when necessary.

Defective inflammatory response in interleukin 6-deficient mice.

Systemic and localized inflammation elicit a number of host responses which include fever, cachexia, hypoglycemia, and major changes in the concentration of liver plasma proteins. Interleukin 6 (IL-6) is considered an important mediator of the inflammatory response, together with IL-1 and tumor necrosis factor alpha (TNF-alpha). The purpose of this study was to unequivocally determine the role of IL-6 in these phenomena making use of IL-6-deficient mice that we have recently generated by gene targeting. We report here that in the absence of IL-6, mice are unable to mount a normal inflammatory response to localized tissue damage generated by turpentine injection. The induction of acute phase proteins is dramatically reduced, mice do not lose body weight and only suffer from mild anorexia and hypoglycemia. In contrast, when systemic inflammation is elicited through the injection of bacterial lipopolysaccharide (LPS), these parameters are altered to the same extent both in wild-type and IL-6-deficient mice, demonstrating that under these conditions IL-6 function is dispensable. Moreover, we show that LPS-treated IL-6-deficient mice produce three times more TNF-alpha than wild-type controls, suggesting that increased TNF-alpha production might be one of the compensatory mechanisms through which a normal response to LPS is achieved in the absence of IL-6. We also show that corticosterone is normally induced in IL-6-deficient mice, demonstrating that IL-6 is not required for the activation of the hypothalamic-pituitary-adrenal axis. Our results reinforce the idea that different patterns of cytokines are involved in systemic and localized tissue damage, and identify IL-6 as an essential mediator of the inflammatory response to localized inflammation.

Interleukin 6 is required for the development of collagen-induced arthritis.

Interleukin-6 (IL-6) is overproduced in the joints of patients with rheumatoid arthritis (RA) and, based on its multiple stimulatory effects on cells of the immune system and on vascular endothelia, osteoclasts, and synovial fibroblasts, is believed to participate in the development and clinical manifestations of this disease. In this study we have analysed the effect of ablating cytokine production in two mouse models of arthritis: collagen-induced arthritis (CIA) in DBA/1J mice and the inflammatory polyarthritis of tumor necrosis factor alpha (TNF-alpha) transgenic mice. IL-6 was ablated by intercrossing an IL-6 null mutation into both arthritis-susceptible genetic backgrounds and disease development was monitored by measuring clinical, histological, and biochemical parameters. Two opposite responses were observed; while arthritis in TNF-alpha transgenic mice was not affected by inactivation of the IL-6 gene, DBA/1J, IL-6(-/-) mice were completely protected from CIA, accompanied by a reduced antibody response to type II collagen and the absence of inflammatory cells and tissue damage in knee joints. These results are discussed in the light of the present knowledge of cytokine networks in chronic inflammatory disorders and suggest that IL-6 receptor antagonists might be beneficial for the treatment of RA.

Extramedullary expansion of hematopoietic progenitor cells in interleukin (IL)-6-sIL-6R double transgenic mice.

Soluble cytokine receptors modulate the activity of their cognate ligands. Interleukin (IL)-6 in association with the soluble IL-6 receptor (sIL-6R) can activate cells expressing the gp130 signal transducer lacking the specific IL-6R. To investigate the function of the IL-6-sIL-6R complex in vivo and to discriminate the function of the IL-6-sIL-6R complex from the function of IL-6 alone, we have established a transgenic mouse model. Double-transgenic mice coexpressing IL-6 and sIL-6R were generated and compared with IL-6 and sIL-6R single-transgenic mice. The main phenotype found in IL-6-sIL-6R mice was a dramatic increase of extramedullary hematopoietic progenitor cells in liver and spleen but not in the bone marrow. In IL-6 single-transgenic mice and sIL-6R single-transgenic mice no such effects were observed. The high numbers of hematopoietic progenitor cells were reflected by a strong increase of peripheral blood cell numbers. Therefore, activators of the gp130 signal transducer like the IL-6-IL-6R complex may represent most powerful stimulators for extramedullary hematopoietic progenitor cells. gp130 activators may become important for the expansion of hematopoietic progenitor cells in vivo and in vitro.

Interleukin 6 causes growth impairment in transgenic mice through a decrease in insulin-like growth factor-I. A model for stunted growth in children with chronic inflammation.

Stunted growth is a major complication of chronic inflammation and recurrent infections in children. Systemic juvenile rheumatoid arthritis is a chronic inflammatory disorder characterized by markedly elevated circulating levels of IL-6 and stunted growth. In this study we found that NSE/hIL-6 transgenic mouse lines expressing high levels of circulating IL-6 since early after birth presented a reduced growth rate that led to mice 50-70% the size of nontransgenic littermates. Administration of a monoclonal antibody to the murine IL-6 receptor partially reverted the growth defect. In NSE/hIL-6 transgenic mice, circulating IGF-I levels were significantly lower than those of nontransgenic littermates; on the contrary, the distribution of growth hormone pituitary cells, as well as circulating growth hormone levels, were normal. Treatment of nontransgenic mice of the same strain with IL-6 resulted in a significant decrease in IGF-I levels. Moreover, in patients with systemic juvenile rheumatoid arthritis, circulating IL-6 levels were negatively correlated with IGF-I levels. Our findings suggest that IL-6-mediated decrease in IGF-I production represents a major mechanism by which chronic inflammation affects growth.

Inducible formation of liver tumors in transgenic mice.

Transgenic mice have been generated with an inducible SV40 t/T antigen construct with the aim of analysing the early changes that take place in the course of liver tumorigenesis. The strictly liver-specific human C-reactive protein (CRP) gene promoter was chosen for the control of the transgene expression because this promoter can be turned on transiently by injection of bacterial lipopolysaccharide. Among 10 independently derived CRP-Tag mouse lines five showed inducible expression of the CRP-Tag transgene in liver. However, only one had a tight control of the transgene with virtually no expression under physiological conditions and high levels of Tag expression after stimulation. Females of this line were used to analyse the progression of liver alterations upon repeated induction of the t/T antigen for different lengths of time. The first signs of transgene-induced liver alterations could be monitored by the activation of the marker enzyme gamma-glutamyltranspeptidase 30 days after the start of the induction program. After 90 days hepatocellular carcinomas were already detectable. Thus, CRP-Tag mice constitute an excellent system to analyse the sequential events that take place during liver carcinogenesis.

The murine rac1 gene: cDNA cloning, tissue distribution and regulated expression of rac1 mRNA by disassembly of actin microfilaments.

A 886 bp cDNA encoding the murine rac1 protein has been isolated. The abundance of rac1 mRNA was determined in fourteen tissues from both mouse and pig. The mRNA 5' non-coding sequence is very rich in G + C, and has the potential to form several stable secondary structures. In addition, this region contains a putative open reading frame of 57 amino acids. Disruption of the actin microfilament network by cytochalasin B in LLC-PK1 cells results in down regulation of rac1 mRNA. In agreement with the proposed role of rac1 in exocytosis, these results could explain the inhibitory effect of cytochalasin B on secretory processes.

Loss of heterozygosity of imprinted genes in SV40 t/T antigen-induced hepatocellular carcinomas.

Expression of the chromosomally linked Insulin-like Growth Factor II (IGF-II) and H19 genes is regulated by parental imprinting during development, since the maternally inherited IGF-II and the paternally inherited H19 alleles are inactive in fetal tissues. Here we show that expression of IGF-II and H19 genes is activated in transgenic mice during SV40 Tag-induced hepatocarcinogenesis and that imprinting of both genes is conserved in the liver tumors. Allelic imbalances of IGF-II and H19 genes and other chromosome 7 markers were detected in one third (13/39) of the hepatocellular carcinomas analysed. A strong bias on the allele retained in the neoplasms was observed, since underrepresentation or complete loss of maternal chromosome 7 was recognised in 12/13 cases. High levels of IGF-II mRNA were expressed by all carcinomas with relative excess of paternal chromosome 7 alleles and suppressed H19 expression was found in the neoplasms lacking the maternal alleles. Overall the results indicate that expression of imprinted genes is involved in progression of experimental liver tumors and suggest that the murine chromosome 7, whose loss may possibly cause the inactivation of a growth-inhibitory gene, is preferentially retained as paternal copy in the liver tumors because of parental imprinting of IGF-II gene.

C/EBPbeta is required for the late phases of acute phase genes induction in the liver and for tumour necrosis factor-alpha, but not Interleukin-6, regulation.

C/EBPbeta is a leucine-zipper transcription factor believed to play an important role in the control of liver functions, and in particular in the transcriptional regulation of acute phase genes in response to several inflammatory stimuli and to recombinant cytokines. Moreover, this factor has been proposed as an important activator of several cytokine genes. We recently described the generation of mice in which the C/EBPbeta gene has been inactivated by gene targeting, showing that they are viable, but present specific defects in the myeloid and lymphoid compartments. Here we demonstrate that C/EBPbeta does indeed play a role in the transcriptional induction of some, but not all, liver acute phase genes. Activation is in particular defective in C/EBPbeta-deficient mice in the later phases of induction, suggesting that the early phases may be triggered by factors other than C/EBPs. Moreover, IL-6 activation is normal and TNFalpha activation is defective in the mutant mice, indicating a differential role of C/EBPbeta in the control of these two cytokines' production.

Gene electrotransfer results in a high-level transduction of rat skeletal muscle and corrects anemia of renal failure.

We have investigated the efficacy of a gene transfer strategy based on plasmid DNA electroinjection for the correction of anemia associated with renal failure. An expression plasmid encoding the rat erythropoietin (EPO) cDNA under the control of the CMV promoter as constructed and utilized for this work. Electroinjection of pCMV/rEPO in different rat muscles yielded sustained and long-term EPO production and secretion. The muscle-produced EPO corrected the anemia in five of six nephrectomized rats, used as a model of renal failure. The efficiency of muscle transduction was comparable in rats and mice injected with equivalent amounts of DNA per kilogram of body weight. These results demonstrate that gene electrotransfer can be applied to produce therapeutically significant levels of erythropoietin in chronic renal failure.

Effect of IL-6 on IGF binding protein-3: a study in IL-6 transgenic mice and in patients with systemic juvenile idiopathic arthritis.

Stunted growth is a common complication of childhood diseases characterized by chronic inflammation or infections. We previously demonstrated that NSE/hIL-6 transgenic mice, overexpressing the inflammatory cytokine IL-6 since early phase of life, showed a marked growth defect associated with decreased IGF-I levels, suggesting that IL-6 is one of the factors involved in stunted growth complicating chronic inflammation in childhood. Here we show that NSE/hIL-6 mice have normal liver IGF-I production, decreased levels of IGF binding protein-3 (IGFBP-3) and increased serum IGFBP-3 proteolysis. Reduced IGFBP-3 levels results in a marked decrease in the circulating 150-kDa ternary complex, even in the presence of normally functional acid labile subunit. Pharmacokinetic studies showed that NSE/hIL-6 mice have accelerated IGF-I clearance. Patients with systemic juvenile idiopathic arthritis (s-JIA), a chronic inflammatory disease characterized by prominent IL-6 production and complicated by stunted growth associated with low IGF-I levels, have markedly decreased IGFBP-3 levels, increased serum IGFBP-3 proteolysis and normal acid labile subunit levels. Our data show that chronic overproduction of IL-6 causes decreased IGFBP-3 levels, resulting in a decreased association of IGF-I in the 150-kDa complex. Decreased levels of IGF-I appear to be secondary to increased clearance.

Overexpression of interleukin-6 in the central nervous system of transgenic mice increases central but not systemic proinflammatory cytokine production.

Production of inflammatory cytokines, including tumor necrosis factor (TNF), interleukin-1 (IL-1) and interleukin-6 (IL-6), in the brain is increased in various diseases. To investigate the relationships between the effect of overproduction of IL-6 in the brain on central and peripheral production of TNF, IL-1 beta and IL-6 itself, we used transgenic mice (NSE-hIL-6) where neuronal human IL-6 expression under the control of the neuronal specific enolase promoter results in astrocytosis and gliosis. These mice had higher cerebral endogenous IL-6 (12-fold), IL-1 beta (12-fold) and TNF (4-fold) production measured in brain homogenates after intracerebroventricular (i.c.v.) injection of 2.5 micrograms LPS, lipopolysaccharide (LPS) than wild-type mice (no TNF or IL-1 were detectable in saline-injected NSE or control mice). Cerebral cytokines production was also increased in NSE-hIL-6 mice treated i.p. with LPS doses that do not normally induce cytokines in the brain. The induction of peripheral (serum or spleen) TNF, IL-1 beta or IL-6 was the same in all these experiments in NSE-hIL-6 and wild-type mice. Furthermore, using microglial cell clone pretreated in vitro with IL-6, we noted an increase in LPS-induced TNF and IL-6 production and proliferation of pretreated cells than control. This study indicates that overproduction of IL-6 in the central nervous system (CNS) may ultimately result in increased central production of inflammatory cytokines, probably due to increased proliferation and activation of the cells which produce cytokine in the CNS.

Efficient immunization of rhesus macaques with an HCV candidate vaccine by heterologous priming-boosting with novel adenoviral vectors based on different serotypes.

Efficient vaccination against viral agents requires a strong T-cell-mediated immune response to clear viral-infected cells. Optimal vaccination can be achieved by administration of recombinant viral vectors encoding phatogen antigens. Adenoviral vectors have attracted considerable attention as potential viral vectors for genetic vaccination owing to their favorable safety profile and potent transduction efficiency following intramuscular injection. However, the neutralizing antibody response against adenoviral capsid proteins following adenoviral vectors injection limits the success of vaccination protocols based on multiple administrations of the same adenoviral serotype. In this work, we describe efficient immunization of rhesus macaques, the preferred model for preclinical assessment, with an HCV candidate vaccine by heterologous priming-boosting with adenoviral vectors based on different serotypes. The induced responses are broad and show significant cross-strain reactivity. Boosting can be delayed for over 2 years after priming, indicating that there is long-term maintenance of resting memory cells.

Characteristics of the adeno-associated virus preintegration site in human chromosome 19: open chromatin conformation and transcription-competent environment.

Adeno-associated virus (AAV) establishes latency in infected cells by integrating into the cellular genome, with a high preference for a unique region, called AAVS1, of the human chromosome 19. The AAV proteins Rep78 and -68 are postulated to initiate the site-specific integration process by binding to a Rep binding site (RBS) in AAVS1. We provide further evidence to corroborate this model by demonstrating that the AAVS1 RBS in human cell lines is located near a DNase I hypersensitive "open" chromatin region and therefore is potentially easily accessible to Rep proteins. This open conformation is maintained in transgenic rats which carry an AAVS1 3. 5-kb DNA fragment and are proficient for Rep-mediated site-specific integration. Interestingly, the core of the DNAse I hypersensitive site in AAVS1 corresponds to a sequence displaying transcriptional enhancer-like properties, suggesting that AAVS1 constitutes a transcription-competent environment. The implications of our findings for AAV physiology and gene therapy are discussed.

Serine hydroxymethyltransferase: origin of substrate specificity.

All forms of serine hydroxymethyltransferase, for which a primary structure is known, have five threonine residues near the active-site lysyl residue (K229) that forms the internal aldimine with pyridoxal phosphate. For Escherichia coli serine hydroxymethyltransferase each of these threonine residues has been changed to an alanine residue. The resulting five mutant enzymes were purified and characterized with respect to kinetic and spectral properties. The mutant enzymes T224A and T227A showed no significant changes in kinetic and spectral properties compared to the wild-type enzyme. The T225A and T230A enzymes exhibited differences in Km and kcat values but exhibited the same spectral properties as the wild-type enzyme. The four threonine residues at positions 224, 225, 227, and 230 do not play a critical role in the mechanism of the enzyme. The T226A enzyme had nearly normal affinity for substrates and coenzymes but had only 3% of the catalytic activity of the wild-type enzyme. The spectrum of the T226A enzyme in the presence of amino acid substrates showed a large absorption maximum at 343 nm with only a small absorption band at 425 nm, unlike the wild-type enzyme whose enzyme-substrate complexes absorb at 425 nm. Rapid reaction studies showed that when amino acid substrates and substrate analogues were added to the T226A enzyme, the internal aldimine absorbing at 422 nm was rapidly converted to a complex absorbing at 343 nm in a second-order process. This was followed by a very slow first-order formation of a complex absorbing at 425 nm.(ABSTRACT TRUNCATED AT 250 WORDS)

Analysis of human/mouse interleukin-6 hybrid proteins: both amino and carboxy termini of human interleukin-6 are required for in vitro receptor binding.

The multifunctional cytokine interleukin-6 (IL-6) is a single polypeptide chain consisting of 184 amino acids in man and 187 amino acids in mouse. Despite the relatively high degree of sequence similarity of these two molecules (about 57%), the biological activity in mouse and human IL-6 shows species specificity. Starting with this observation, we constructed interspecies hybrids with the goal of defining which segments of the human IL-6 molecule are involved in human receptor binding. In this manner we generated multiple amino acid substitution mutants which do not contain insertions or deletions as compared with the parental proteins, and which, therefore, should not show dramatic changes in folding. Using two biological assays on cells of human and mouse origin and a recently developed in vitro binding assay to recombinant soluble human IL-6 receptor, we obtained results which indicate that both the amino and carboxy termini are necessary and sufficient for efficient binding, but that the carboxy terminus plays the dominant role in receptor recognition.

Severe factor X deficiency in pregnancy: case report and review of the literature.

Isolate factor X deficiency is an extremely rare clotting factor disorder inherited in autosomal recessive fashion and pregnancy in a homozygous patient is frequently complicated by recurrent miscarriage, uterine bleeding and premature labour. Eleven pregnancies in seven patients affected by FX deficiency have been reported in the literature. Two additional pregnancies have been reported in a FX variant (FX Friuli). We present a new case of successful at term pregnancy in a homozygous patient.

IL-6 expression in neurons of transgenic mice causes reactive astrocytosis and increase in ramified microglial cells but no neuronal damage.

Growing evidence suggests that aberrant production of inflammatory cytokines within the central nervous system (CNS) contributes to the development of pathological conditions. To test the cause-effect relationship between the overproduction of interleukin-6 (IL-6) in the CNS and the onset of neuropathological changes, we have generated transgenic mice in which human IL-6 expression has been targeted to the neurons by using the rat neuron-specific enolase promoter. These mice develop reactive astrocytosis and an increase in ramified microglial cells but do not show histological or behavioural signs of neuron damage at the light microscope level. We thus conclude that a constant release of human IL-6 by neuronal subpopulations in mice is sufficient to activate cells potentially capable of modulating the local immune response, but at the same time is compatible with normal neuron functions.