Programa piloto de higiene dentária escolar

Este programa, elaborado após termos tido conhecimento real do problema — cárie dentária — na população escolar de Porto Alegre, visa sugerir alguns elementos para a satisfação das necessidades de tratamento preventivo e curativo da cárie dentária. O programa piloto de higiene dentária escolar, planejado para ser executado em uma area específica do município de Porto Alegre, apresenta características próprias e definidas e se desenvolverá em bases incrementais. Poderá servir como modelo de amplos programas de higiene escolar, e, principalmente como campo de treinamento e aperfeiçoamento de profissionais, os quais receberão orientação técnica e coordenação administrativa para a formação de equipes capazes de desenvolverem um programa de higiene dentária escolar.

Planejamento de um programa piloto em bases incrementais

Discute-se a importância do planejamento na elaboração de um programa incremental. Determina-se as necessidades de tratamento, tomando por base dados de um levantamento em um grupo de crianças da cidade de Pôrto Alegre. Comparam-se os recursos disponíveis na comunidade com as necessidades de tratamento. São apresentadas e analisadas algumas hipóteses de solução do problema cárie dentária. É selecionado um específico programa de ação, em função do objetivo e da política do serviço.

Conjunctivitis as a sign of persistent SARS-COV-2 infection? An observational study and report of late symptoms

PURPOSE

To investigate if symptomatic conjunctivitis during the recovery phase of the disease could be associated to a persistent presence of SARS-CoV-2 in the upper respiratory tract. Secondary end points were to analyze the presence of SARS-CoV-2 in the conjunctiva of ocular symptomatic patients and to record the presence of ocular disturbances at this point of the disease.

METHODS

An observational study including consecutive COVID19 patients treated at Humanitas Clinical and Research Hospital who were attending for nasopharyngeal swab to confirm the resolution of SARS-CoV-2 infection and end of isolation. We examined 129 consecutive patients from May to June 2020. The primary end point was to determine if symptomatic conjunctivitis at this point of the disease could be associated to a persistent presence of SARS-CoV-2 in the upper respiratory tract. Secondary end points were to analyze the presence of SARS-CoV-2 in the conjunctiva of ocular symptomatic patients and to record the presence of ocular disturbances at this point of the disease.

RESULTS

One hundred twenty eight patients were included, 9.38% had conjunctivitis, none resulted positive to conjunctival PCR swab test, while two of them had positive nasopharyngeal result. Mean time elapsed since the first COVID-19 positive swab to the time of examination was 6 weeks (  ± 3). The only significant association was the presence of conjunctivitis with older age (65.3  ±  12.7 vs 56.7  +  13.5. p  =  0.046). Nasopharyngeal swab resulted positive in 22 patients (17.19%). While 88 patients (68.2%) did not have any ocular complain during their COVID19 disease. The 40 patients (31.8%) reporting ocular disturbances complained about: redness (25.43%), tearing (19.53%), burning (18.35%), foreign body sensation (17.18%), itching (15.62%), and discharge (12.5%).

CONCLUSION

This study showed that late conjunctivitis cannot be considered as a marker of persistent infection when patients are sent to confirm the resolution of SARS-CoV-2 infection.

HDAC3 Regulates Gingival Fibroblast Inflammatory Responses in Periodontitis

Histone deacetylases (HDACs) are important regulators of gene expression that are aberrantly regulated in several inflammatory and infectious diseases. HDAC inhibitors (HDACi) suppress inflammatory activation of various cell types through epigenetic and non-epigenetic mechanisms, and ameliorate pathology in a mouse model of periodontitis. Activation of gingival fibroblasts (GFs) significantly contributes to the development of periodontitis and the anaerobic bacterium Porphyromonas gingivalis plays a key role in driving chronic inflammation. Here, we analyzed the role of HDACs in inflammatory responses of GFs. Pan-HDACi suberoylanilide hydroxamic acid (SAHA) and/or ITF2357 (givinostat) significantly reduced TNFα- and P. gingivalis–inducible expression and/or production of a cluster of inflammatory mediators in healthy donor GFs (IL1B, CCL2, CCL5, CXCL10, COX2, and MMP3) without affecting cell viability. Selective inhibition of HDAC3/6, but not specific HDAC1, HDAC6, or HDAC8 inhibition, reproduced the suppressive effects of pan-HDACi on the inflammatory gene expression profile induced by TNFα and P. gingivalis, suggesting a critical role for HDAC3 in GF inflammatory activation. Consistently, silencing of HDAC3 expression with siRNA largely recapitulated the effects of HDAC3/6i on mRNA levels of inflammatory mediators in P. gingivalis–infected GFs. In contrast, P. gingivalis internalization and intracellular survival in GFs remained unaffected by HDACi. Activation of mitogen-activated protein kinases and NFκB signaling was unaffected by global or HDAC3/6-selective HDACi, and new protein synthesis was not required for gene suppression by HDACi. Finally, pan-HDACi and HDAC3/6i suppressed P. gingivalis–induced expression of IL1B, CCL2, CCL5, CXCL10, MMP1, and MMP3 in GFs from patients with periodontitis. Our results identify HDAC3 as an important regulator of inflammatory gene expression in GFs and suggest that therapeutic targeting of HDAC activity, in particular HDAC3, may be clinically beneficial in suppressing inflammation in periodontal disease.

Delayed Cutaneous Hypersensitivity Reaction to Carcinoembryonic Antigen in Cancer Patients

The delayed cutaneous hypersensitivity reaction to carcinoembryonic antigen (CEA) was tested in 84 patients with different diseases including large bowel adenocarcinoma and breast carcinoma, with or without metastasis, liver cirrhosis and inflammatory or degenerative diseases. Positive skin test to CEA was observed in a small proportion (11 %) of the patients tested. No difference in positive skin test reactions was observed in the 6 different groups of patients. Similar delayed cutaneous hypersensitivity reactions were found to various amount of CEA ranging from 0.5 to 25 μg. No correlation was seen between the results of skin test and blood CEA levels.

Inhibition of Human Melanoma Growth in Nude Mice by Autologous, Alloactivated Peripheral Blood Lymphocytes

Peripheral blood lymphocytes of melanoma patients were stimulated in vitro by a pool of allogeneic lymphocytes and shown to be cytotoxic against autologous melanoma cells. To evaluate the in vivo antitumor activity of the cytotoxic alloactivated autologous peripheral blood lymphocytes, tumor neutralization (Winn) assay was carried out by injecting such lymphocytes admixed with autologous melanoma cells in athymic BALB/c nude mice. In 3 of 6 cases, complete inhibition of tumor growth was obtained at lymphocytes to tumor cells ratio of 10:1 and in one case also of 5:1. In all cases the appearance of tumors was delayed and the growth rate was significantly reduced in a dose-dependent fashion as compared to control mice injected with tumor cells alone. We conclude that in vitro alloactivated peripheral blood lymphocytes can inhibit and/or impair the growth of autologous melanoma cells in nude mice.

Loss of Heterozygosity of Dq Alpha Gene in Human Malignant Melanoma

DNAs from human melanoma cells, used at early in vitro passage, were evaluated by Southern blot analysis for somatic loss of heterozygosity at the DQ alpha gene. A total of 7 melanomas, 3 primary and 4 metastatic derived from 5 different patients were studied; in one case (pt 665) cell lines were derived from two anatomically different subcutaneous metastasis, whereas in a second case (pt 9923) both the primary tumor and a lymph node metastasis were available. Restriction length polymorphism (RFLP) analysis, performed on autologous peripheral blood lymphocyte (PBL) DNA digested with different enzymes, showed a pattern of bands compatible with the constitutional heterozygous typing at DQ alpha gene in 4 cases whereas 1 case revealed an homozygous typing. When melanoma DNAs were analysed, 1 out of the 4 informative cases (pt 1007) showed a loss of a diagnostic fragment for DQ alpha gene when digested with both Taq I and Bgl I enzymes. These results indicate that class II allelic losses detectable by RFLP can be found on malignant melanoma and add further complexity on the involvement of chromosome 6 whose cytogenetic abnormality are the most consistent in this human neoplasia.

The histone deacetylase inhibitor givinostat (ITF2357) exhibits potent anti-tumor activity against CRLF2-rearranged BCP-ALL

Leukemias bearing CRLF2 and JAK2 gene alterations are characterized by aberrant JAK/STAT signaling and poor prognosis. The HDAC inhibitor givinostat/ITF2357 has been shown to exert anti-neoplastic activity against both systemic juvenile idiopathic arthritis and myeloproliferative neoplasms through inhibition of the JAK/STAT pathway. These findings led us to hypothesize that givinostat might also act against CRLF2-rearranged BCP-ALL, which lack effective therapies. Here, we found that givinostat inhibited proliferation and induced apoptosis of BCP-ALL CRLF2-rearranged cell lines, positive for exon 16 JAK2 mutations. Likewise, givinostat killed primary cells, but not their normal hematopoietic counterparts, from patients carrying CRLF2 rearrangements. At low doses, givinostat downregulated the expression of genes belonging to the JAK/STAT pathway and inhibited STAT5 phosphorylation. In vivo, givinostat significantly reduced engraftment of human blasts in patient-derived xenograft models of CRLF2-positive BCP-ALL. Importantly, givinostat killed ruxolitinib-resistant cells and potentiated the effect of current chemotherapy. Thus, givinostat in combination with conventional chemotherapy may represent an effective therapeutic option for these difficult-to-treat subsets of ALL. Lastly, the selective killing of cancer cells by givinostat may allow the design of reduced intensity regimens in CRLF2-rearranged Down syndrome-associated BCP-ALL patients with an overall benefit in terms of both toxicity and related complications.

Lymphocyte subpopulations and intima media thickness in primary antiphospholipd syndrome

The aim of this study was to evaluate a possible association between lymphocyte subsets and intima media thickness (IMT) of carotid arteries in primary antiphospholipid syndrome (PAPS). We used a cross-sectional study on PAPS patients ( n = 18) and healthy controls ( n = 16). IgG anti-cardiolipin antibody (aCL), IgG anti-β2glycoprotein-I (anti-β2GPI), IgG anti-β2glycoprotein-I complexed to oxidized low-density lipoprotein (oxLDL) and to a specific oxidized moiety of LDL (oxLig1), and β2GPI-oxLDL were measured by ELISA. Lymphocyte immunophenotyping was performed using pairs of monoclonal antibodies directly labelled with fluorescein isothiocyanate, or phycoerythrin or phycoerythrin-Texas-red-X. Intima media thickness (IMT) of carotid arteries was determined by high-resolution sonography. Total peripheral blood lymphocytes did not differ between PAPS and controls. Memory CD4+/CD45RO + T cells were lower in PAPS than controls ( P = 0.0007) as well as CD16+56+ natural killer cells ( P = 0.02). In PAPS memory T CD45RO + cells positively correlated with IgG anti-β2GPI-oxLig1 ( P = 0.002) and to IMT of carotid arteries (common carotid P = 0.02, bifurcation P = 0.007). Naïve CD4+/CD45RA+ T cells inversely correlated with β2GPI-oxLDL ( P = 0.009). The relation between IgG anti-β2GPI-oxLig1 and IMT of carotid arteries with memory CD45RO + T lymphocytes suggests a role for the latter in PAPS related atherogenesis.

Reduced SNAP-25 increases PSD-95 mobility and impairs spine morphogenesis

Impairment of synaptic function can lead to neuropsychiatric disorders collectively referred to as synaptopathies. The SNARE protein SNAP-25 is implicated in several brain pathologies and, indeed, brain areas of psychiatric patients often display reduced SNAP-25 expression. It has been recently found that acute downregulation of SNAP-25 in brain slices impairs long-term potentiation; however, the processes through which this occurs are still poorly defined. We show that in vivo acute downregulation of SNAP-25 in CA1 hippocampal region affects spine number. Consistently, hippocampal neurons from SNAP-25 heterozygous mice show reduced densities of dendritic spines and defective PSD-95 dynamics. Finally, we show that, in brain, SNAP-25 is part of a molecular complex including PSD-95 and p140Cap, with p140Cap being capable to bind to both SNAP-25 and PSD-95. These data demonstrate an unexpected role of SNAP-25 in controlling PSD-95 clustering and open the possibility that genetic reductions of the protein levels - as occurring in schizophrenia - may contribute to the pathology through an effect on postsynaptic function and plasticity.

Selective anti-leukaemic activity of low-dose histone deacetylase inhibitor ITF2357 on AML1/ETO-positive cells

We analysed the in vitro effects of a new hydroxamate derivative, ITF2357, on AML cells. ITF2357 potently induced histone acetylation. ITF2357 0.1 microM blocked proliferation and induced apoptosis in AML1/ETO-positive Kasumi-1 cells, while AML1/ETO-negative HL60, THP1 and NB4 cell lines were sensitive only to 1 microM ITF2357. Apoptosis was induced by 0.1 microM ITF2357 in AML1/ETO-positive primary blasts and U937-A/E cells induced to express AML1/ETO, but not in U937-A/E cells non-expressing AML1/ETO. In Kasumi-1 cells 0.1 microM ITF2357 induced AML1/ETO degradation through a caspase-dependent mechanism. ITF2357 0.1 microM also determined DNMT1 efflux from, and p300 influx to, the nucleus. Moreover, 0.1 microM ITF2357 determined local H4 acetylation and release of DNMT1, HDAC1 and AML1/ETO, paralleled by recruitment of p300 to the IL-3 gene promoter. ITF2357 treatment, however, did not induce re-expression of IL-3 gene. Accordingly, the methylation level of IL-3 promoter, as well as of several other genes, was unmodified. In conclusion, ITF2357 emerged as an anti-leukaemic agent very potent on AML cells, and on AML1/ETO-positive cells in particular. More relevantly, clearly emerged from our results that ITF2357 could be an ideal agent to treat AML subtypes presenting AML1/ETO fusion protein which determine HDAC involvement in leukaemogenesis.

The histone deacetylase inhibitor ITF2357 has anti-leukemic activity in vitro and in vivo and inhibits IL-6 and VEGF production by stromal cells

We have investigated the activity of ITF2357, a novel hydroxamate histone deacetylase inhibitor, on multiple myeloma (MM) and acute myelogenous leukemia (AML) cells in vitro and in vivo. ITF2357 induced apoptosis in 8/9 MM and 6/7 AML cell lines, as well as 4/4 MM and 18/20 AML freshly isolated cases, with a mean IC(50) of 0.2 microM. ITF2357 activated the intrinsic apoptotic pathway, upregulated p21 and downmodulated Bcl-2 and Mcl-1. The drug induced hyperacetylation of histone H3, H4 and tubulin. When studied in more physiological conditions, ITF2357 was still strongly cytotoxic for the interleukin-6 (IL-6)-dependent MM cell line CMA-03, or for AML samples maximally stimulated by co-culture on mesenchymal stromal cells (MSCs), but not for the MSCs themselves. Interestingly, ITF2357 inhibited the production of IL-6, vascular endothelial growth factor (VEGF) and interferon-gamma by MSCs by 80-95%. Finally, the drug significantly prolonged survival of severe combined immunodeficient mice inoculated with the AML-PS in vivo passaged cell line already at the 10 mg/kg oral dose. These data demonstrate that ITF2357 has potent anti-neoplastic activity in vitro and in vivo through direct induction of leukemic cell apoptosis. Furthermore, the drug inhibits production of growth and angiogenic factors by bone marrow stromal cells, in particular IL-6 and VEGF.

The TB structural genomics consortium: a resource for Mycobacterium tuberculosis biology

The TB Structural Genomics Consortium is an organization devoted to encouraging, coordinating, and facilitating the determination and analysis of structures of proteins from Mycobacterium tuberculosis. The Consortium members hope to work together with other M. tuberculosis researchers to identify M. tuberculosis proteins for which structural information could provide important biological information, to analyze and interpret structures of M. tuberculosis proteins, and to work collaboratively to test ideas about M. tuberculosis protein function that are suggested by structure or related to structural information. This review describes the TB Structural Genomics Consortium and some of the proteins for which the Consortium is in the progress of determining three-dimensional structures.

Insoluble and soluble immune complexes activate neutrophils by distinct activation mechanisms: changes in functional responses induced by priming with cytokines

BACKGROUND

Rheumatoid synovial fluid contains both soluble and insoluble immune complexes that can activate infiltrating immune cells such as neutrophils.

OBJECTIVES

To determine if these different complexes activate neutrophils through similar or different receptor signalling pathways. In particular, to determine the circumstances which result in the secretion of tissue damaging reactive oxygen metabolites and granule enzymes.

METHODS

Blood neutrophils were incubated with synthetic soluble and insoluble immune complexes and the ability to generate reactive oxidants tested by luminescence or spectrophotometric assays that distinguished between intracellular and extracellular production. Degranulation of myeloperoxidase and lactoferrin was determined by western blotting. The roles of FcgammaRII (CD32) and FcgammaRIIIb (CD16) were determined by incubation with Fab/F(ab')(2) fragments before activation. The effect of cytokine priming was determined by incubation with GM-CSF.

RESULTS

Insoluble immune complexes activated unprimed neutrophils, but most of the oxidants produced were intracellular. This activation required FcgammaRIIIb, but not FcgammaRII function. Soluble complexes failed to activate unprimed neutrophils but generated a rapid and extensive secretion of reactive oxygen metabolites when the cells were primed with granulocyte-macrophage colony stimulating factor (GM-CSF). This activity required both FcgammaRII and FcgammaRIIIb function. Insoluble immune complexes activated the release of granule enzymes from primed or unprimed neutrophils, but the kinetics of release did not parallel those of secretion of reactive oxygen metabolites. Only primed neutrophils released enzymes in response to soluble complexes.

CONCLUSIONS

Soluble and insoluble immune complexes activate neutrophils by separate receptor signalling pathways. Profound changes in neutrophil responsiveness to these complexes occur after cytokine priming.

Fcgamma receptors in autoimmune diseases

Fcgamma-receptors (Fcgamma-R) recognise the Fc portion of IgG and thus form a link between humoral and cellular immunity. These receptors are expressed by a variety of immune cells, and they function in the binding of immune complexes or IgG-opsonised particles, such as microbial pathogens. The are three major types of Fcgamma-R, namely Fcgamma-RI (CD64), Fcgamma-RII (CD32) and Fcgamma-RIII (CD16), and these differ in their ability to bind IgG and complexes. There are many isoforms of these receptors and a number of recently identified polymorphisms in their structure. This review describes the structure and function of these Fcgamma-Rs, and highlights how gene deficiencies and polymorphisms may contribute to the pathology of human diseases.

Antioxidant susceptibility of pathogenic pathways in subjects with antiphospholipid antibodies: a pilot study

The pathogenesis of antiphospholipid antibody (aPL) related thrombosis is multifactorial and includes, amongst others, enhanced coagulation activation measured as prothrombin fragment 1 + 2 (F1 + 2), elevated plasma levels of von Willebrand factor (vWF), plasminogen activator inhibitor (PAI) and endothelin-1 (ET-1) as well as heightened thromboxane generation and lipid peroxidation. To evaluate the antioxidant susceptibility of some of the above pathways, probucol (500 mg/d orally, a cholesterol lowering agent bearing antioxidant properties) was administered for a three week period to 14 subjects with aPL and to seven healthy controls. At baseline aPL participants showed higher plasma levels of vWF (P = 0.006), ET-1 (P = 0.0002) and enhanced urinary excretion of 11-dehydro-thromboxane-B2 (TXB2) (P = 0.0004), F2-isoprostanes (marker of lipid peroxidation) (P = 0.02) and albumin (P = 0.04) than controls. In the aPL group baseline IgG anticardiolipin (aCL) titre positively related with urinary TXB2 (r2 = 0.43, P = 0.01) and inversely with urinary NOx (r2 = -0.6, P = 0.005) whereas urinary NOx and TXB2 were negatively correlated (r2 = -0.42, P = 0.01). After the treatment period significant decreases from baseline values were noted for PAI (P = 0.01), ET-1 (P = 0.006), TXB2 (P = 0.02), F2-isoprostanes (P = 0.01) and albuminuria (P = 0.01) in aPL participants but not in controls. These pilot data support oxidative sensitive mechanisms and a potential role for antioxidant treatment in the pathogenesis of aPL induced vasculopathy.

Involvement of iron (ferric) reduction in the iron absorption mechanism of a trivalent iron-protein complex (iron protein succinylate)

Iron protein succinylate is a non-toxic therapeutic iron compound. We set out to characterise the structure of this compound and investigate the importance of digestion and intestinal reduction in determining absorption of the compound. The structure of the compound was investigated by variable temperature Mössbauer spectroscopy, molecular size determinations and kinetics of iron release by chelators. Intestinal uptake was determined with radioactive compound force fed to mice. Reduction of the compound was determined by in vitro incubation with intestinal fragments. The compound was found to contain only ferric iron, present as small particles including sizes below 10 nm. The iron was released rapidly to chelators. Digestion with trypsin reduced the molecular size of the compound. Intestinal absorption of the compound was inhibited by a ferrous chelator (ferrozine), indicating that reduction to ferrous iron may be important for absorption. The native compound was a poor substrate for duodenal reduction activity, but digestion with pepsin, followed by pancreatin, released soluble iron complexes with an increased reduction rate. We conclude that iron protein succinylate is absorbed by a mechanism involving digestion to release soluble, available ferric species which may be reduced at the mucosal surface to provide ferrous iron for membrane transport into enterocytes.

Reconstruction of intrathoracic oesophagus using tubular lateral thigh free flap

The gastric pull-up or pharyngogastroplasty is the most widely used technique in reconstructing the digestive tract in cases of distal oesophageal tumours. This operation consists of drawing the stomach or part of it up through the chest and mediastinic region to the neck where a mucosal anastomosis with the residual pharyngeal tract is made. The most feared complication is proximal necrosis of the gastric stump with salivary fistulae usually followed by a mediastinitis. In the presence of such a complication the surgeon must tackle the challenge of reconstructing the missing part of the intrathoracic digestive tract. We describe the case of a patient in whom the missing intrathoracic oesophagus, following complete necrosis of a previously performed pharyngogastroplasty, was reconstructed using a revascularized lateral thigh free flap.