ABSTRACT
Introduction: The present study aimed to examine changes insubgingival microbiota and clinical parameters before and afterplacement of bracket.Methods: Clinical parameters such as plaque index (PI),probing depth (PD), bleeding on probing (BOP), clinicalattachment level (CAL), and gingival index (GI) were recorded.Additionally, subgingival microbial samples were collected from30 individuals aged between 13 and 25.A total of 15 individualsas the control group were matched in terms of age and sexwithout needing orthodontic treatment using specific primers.Furthermore, SYBER Green Real-Time PCR was conducted todetermine bacterial flora in stored samples. All the mentionedprocedures were reexamined in the experimental and controlgroups three months after band and bracket bonding. Adescriptive analysis was conducted, and paired t-test andWilcoxon test were employed for differences between thegroups (P<0.05).Results: No changes in the level of clinical attachment wereseen, but scores for plaque index, bleeding on probing andgingival index increased 3 months after placement of bracketin the experimental group (P<0.05). P. nigrescence in theexperimental group increased after placement of bracketscompared to the control group, but P. gingivalis and T.Denticola proportions increased.Conclusions: Fixed orthodontic appliances may raise thegrowth of periodontopathogenic bacteria and consequentlyleads to gingival inflammation without destructive effect ondeep periodontal tissues.
ABSTRACT
Development of an effective vaccine is highly needed in order to restrict the AIDS pandemic. DNA vaccines initiate both arms of immunity without the potential of causing disease. HIV-1 p24 and gp41 [gag and env] proteins play important roles in viral pathogenesis and are effective candidates for immune induction and vaccine design. In this study, new DNA vaccine candidates constructed from HIV-1 fused p24- gp41 or gp41 alone were evaluated in Balb/c mice for induction of cellular and humoral immune responses. Recombinant plasmids, pcDNA3.1/Hygro expression vector containing immunogenic sequences of fused p24-gp41 or gp41alone were produced. Dendrosome used as a system for carrying vectors in laboratory animals, and an IL-12 containing vector [pCAGGS-IL-12] was co-immunized with the p24-gp41 vector as a genetic adjuvant. Induction of effective immune responses against the designed vectors as DNA vaccine candidates in Balb/c mice was evaluated. Levels of total antibodies, IgG isotypes [IgG2a and IgG1]? IFN-alpha and IL-4 were measured by ELISA. MTT assay was used to evaluate lymphoproliferation. The results confirmed that the immunogenic epitopes of both p24 and gp41 genes are highly effective inducers of immune responses, and administration of fused p24-gp41 alone or along with IL-12 resulted in further enhancement of immune responses. Group 4 that received fused fragments [p24-gp41] along with an IL-12 expressing vector demonstrated a significantly higher Stimulation Index [SI] and IFN-alpha production [p<0.0001] with a significant increase in IgG2a/IgG1 ratio, indicating the stimulation of CMI towards Th1. Although gp41 containing vector [group 6] also showed significant increases in both proliferation and IFN-alpha production, the responses were persistently lower than that of p24-gp41 containing vectors. Total antibody production was highest in group 6 as expected. Dendrosome proved to be an efficient carrier of recombinant plasmids constructed in this study. Further studies are necessary to evaluate these constructs as HIV vaccine candidates