Effects of Calcium Hydroxide Intracanal Medications on T Helper (Th1, Th2, Th9, Th17, and Tfh) and Regulatory T (Treg) Cell Cytokines in Apical Periodontitis: A CONSORT RCT.

INTRODUCTION: This Consolidated Standards of Reporting Trials randomized clinical trial investigated T helper (Th1, Th2, Th9, Th17, and Tfh) and regulatory T (Treg) cell-type cytokines and their networks in apical periodontitis (AP). We also assessed the effects of calcium hydroxide [Ca(OH)2] intracanal medications (ICMs) on helper T and Treg cell-type cytokines. METHODS: Twenty teeth with primary endodontic infection and apical periodontitis were randomly divided into two groups: Ca(OH)2 + saline solution (n = 10) and Ca (OH)2 + 2% chlorhexidine-gel (n = 10). Samples were collected from the periradicular tissue fluid (PTF) before (PTFs1) and after 14 days of ICMs (PTFs2). The Human High Sensitivity T Cell Panel was used to quantify target T-helper (Th)1: interelukin (IL)-2, IL-12, and interferon-gamma (IFN-γ); Th2: IL-4, IL-5, and IL-13; Th9: IL-9; Th17: IL-17; T follicular helper cells (Tfh): IL-21; and Treg-cell-type cytokine: IL-10. RESULTS: Th1-type cytokines were higher than Th2-type ones, at PTFs1. Positive (+) associations were found among all Th1-type cytokines and all Th2-type cytokines. There were negative (-) correlations between all Th1- and Th2-type cytokines. Size of radiolucent lesions and symptoms (tenderness to percussion and/or pain on palpation) were positively correlated with Th1-type cytokines, IL-17, and IL-21 but negatively correlated with Th2-type cytokines and IL-10 (all, P < .001). Both ICMs increased Th2-type cytokines and IL-10 (P < .05) and decreased Th1-type cytokines, IL-17, and IL-21 (P < .05), with no differences among them (P > .05). CONCLUSIONS: Complex T-cell cytokine networks are involved in AP. Both Ca(OH)2 ICMs effectively increased IL-4, IL-5, IL-10, and IL-13 and lowered IL-2, IL-12, IL-17, IL-21, and IFN-γ.

Clinical influence of calcium hydroxide intracanal medications on matrix metalloproteinases and tissue inhibitors of metalloproteinases in apical periodontitis.

OBJECTIVES: This study investigated the influence of calcium hydroxide intracanal medications on the levels of metalloproteinases (MMPs) and their tissue inhibitors (TIMPs) in apical periodontitis (AP). MATERIALS AND METHODS: Twenty primarily infected root canals with AP were randomly divided into two groups: Ca(OH)2 + sterile saline solution (SSL) group and Ca(OH)2 + 2% chlorhexidine gel (CHX gel) group. We collected samples from the periradicular tissue fluid (PTF) before (s1) and after 14 days of intracanal medication (s2). MMP-1, MMP-2, MMP-9, TIMP-1, and TIMP-2 were measured by ELISA assay. RESULTS: MMP-1, MMP-2, MMP-9, TIMP-1, and TIMP-2 were detected in all PTF samples at s1 and s2 (20/20). At s1, MMP-2 and MMP-9 were detected at higher levels than MMP-1 (p < .05). Higher levels of TIMP-1 than TIMP-2 were found in AP (p < .05). Additionally, we detected higher MMP-1, MMP-2, and MMP-9 over TIMP-1 and TIMP-2 levels in AP (p < .05). At s2, Ca(OH)2 + SSL was as effective as Ca(OH)2 + 2% CHX gel in lowering the levels of MMP-1, MMP-2, and MMP-9 after 14 days of intracanal medication, with no significant difference between them (p > .05). Both Ca(OH) 2 intracanal medications had no significant impact on the levels of TIMP-1 and TIMP-2 (both p > .05). At s2, TIMP-1 levels were higher than TIMP-2 (p < .05). Moreover, there were positive correlations between the levels of MMP-1 and TIMP-1 and MMP-1 and TIMP-2 (p < .05). CONCLUSIONS: Calcium hydroxide medications effectively lowered the levels of MMP-1, MMP-2, and MMP-9 in periapical tissues after 14 days of treatment, with no difference between them. Moreover, the calcium hydroxide intracanal medications tested here had no impact in TIMP-1 and TIMP-2 in periapical tissues. CLINICAL RELEVANCE: MMPs and TIMPs play an essential role in the degradation of the extracellular matrix. The imbalance MMPs and TIMPs can cause periapical tissue destruction. Therefore, the reestablishment of the balance between activated MMPs and TIMPs with root canal therapy is essential to restore tissue homeostasis.

Clinical Investigation of Matrix Metalloproteinases, Tissue Inhibitors of Matrix Metalloproteinases, and Matrix Metalloproteinase/Tissue Inhibitors of Matrix Metalloproteinase Complexes and Their Networks in Apical Periodontitis.

INTRODUCTION: This clinical study investigated the levels of metalloproteinases (MMPs) and their tissue inhibitors (TIMPs) and respective forms (MMP/TIMP complexes) in apical periodontitis to determine their networks in the development of clinical/radiographic features, thus quantifying the levels of endotoxins (lipopolysaccharides) present in primarily infected root canals with apical periodontitis. METHODS: Twenty primarily infected root canals with apical periodontitis were selected. The presence of pain on palpation, tenderness to percussion, and the size of the radiographic lesion were recorded. The levels of MMPs (MMP-1, -2, and -9), TIMPs (TIMP-1 and -2), and their MMP/TIMP complexes (MMP-1/TIMP-1, MMP-1/TIMP-2, MMP-2/TIMP-1, MMP-2/TIMP-2, MMP9/TIMP-1, and MMP-9/TIMP-2) present in the periapical interstitial fluid were measured using the enzyme-linked immunosorbent assay. The kinetic chromogenic LAL test was used to quantify endotoxins. RESULTS: A higher mean level of MMP-9 (968.35 ± 342.00 pg/mL) was followed by MMP-2 (894.00 ± 591.62 pg/mL) and MMP-1 (789.43 ± 342.83 pg/mL). The linear regression analysis revealed a positive association of MMP-1 with both MMP-2 and MMP-9 (all P < .001). TIMP-1 (481.79 ± 86.09 pg/mL) (24/24) was found in higher levels than TIMP-2 (206.45 ± 86.09 pg/mL) (P < .05), including a positive correlation of MMP-1 with both TIMP-1 and TIMP-2 (all P < .05). Higher mean levels of MMP1, -2, and -9 were found in teeth with larger-size radiolucent lesions (>7 mm) compared with smaller ones (≤7 mm) (all P < .01). Higher levels of MMP-1 decreased the chance of TTP, whereas MMP-9 (odds ratio = 0.97) increased the chance of pain on percussion (odds ratio = 1.01). Higher levels of endotoxins present in root canals were positively correlated with larger amounts of MMP -9 (P < .05). CONCLUSIONS: MMPs, TIMPs, and their complexes (MMP/TIMP) are involved in apical periodontitis by interacting with complex networks in the development of clinical features and the severity of bone destruction.

Effect of Baculovirus spodoptera isolates in Spodoptera frugiperda (J.E. Smith) (Lepidoptera: Noctuidae) larvae and their characterization by RAPD

The total of 22 Baculovirus isolates surveyed in different corn producing regions in Brazil were used against fall armyworm, Spodoptera frugiperda (J.E. Smith). The viruses were purified and their suspensions were used to feed fall armyworm larvae from 4th and 5th instar. The mortality rate was checked daily and the infected larvae were frost after death, what generally occurred between the 5th and 7th day after virus ingestion. The 22 Baculovirus isolates were used in six concentrations (from 10³ to 10(8) polyhedra/ml) and one check treatment with water. Mortality rate, larval period, pupal period, pupa weight and lethal concentration (LC50) were determined for all isolates. Significant differences were found among all isolates and different concentrations, also interaction between isolate x virus concentration for all characteristics evaluated, except for pupal period. Amplification patterns of 54 RAPD markers, being 41 polymorphic among the isolates, were used to evaluate the genetic distance and its correlation with the fall armyworm larvae mortality rate. The genetic diversity calculated by the Jaccard's coefficient using the molecular data allowed a division of the isolates into two groups, with a high level of confidence. These groups did not present any association with the mortality rate caused by the isolates or with their geographical distribution. However, a RAPD fragment OPW04.2280 was highly associated with the larvae mortality rate and with LC50, explaining 23 and 65 percent of the phenotypic variation for these traits among the isolates, respectively.

Foram utilizados 22 isolados de vírus amostrados em diferentes regiões produtoras de milho do Brasil. Os vírus foram purificados e suas suspensões fornecidas a lagartas sadias do 3° e 4° ínstar de Spodoptera frugiperda (J.E. Smith). A mortalidade foi avaliada diariamente, e as lagartas infectadas foram congeladas logo após sua morte, o que em geral ocorreu do 5° ao 7° dia após ingestão do vírus. Os isolados foram usados em seis concentrações (10³ a 10(8) poliedros/ml) e uma testemunha (água). Os percentuais de mortalidade, duração do período larval e período pupal, peso de pupa e a concentração letal (CL50) foram determinados para todos os isolados. Foram observadas diferenças significativas entre todos os isolados e concentrações testadas para todos os parâmetros avaliados, e também foi constatada a presença da interação isolado x concentração, exceto para período pupal. Os padrões de amplificação de 54 marcadores RAPD, sendo 41 polimórficos, foram utilizados para avaliar a distância genética e a sua correlação com os índices de mortalidade das lagartas. A divergência genética calculada pelo coeficiente Jaccard utilizando os dados moleculares permitiu dividir os isolados em dois grupos, com um elevada confiabilidade. O agrupamento não apresentou associação com a taxa de mortalidade causada pelos isolados ou com sua distribuição geográfica. No entanto, um fragmento de RAPD OPW04.2280 apresentou-se altamente associado com a mortalidade das lagartas e com a CL50, explicando 23 por cento e 65 por cento da variação fenotípica para essas características entre os isolados virais, respectivamente.