Greater Inflammatory Reaction Research Articles

Evaluation of Porcine Collagen Membranes Used with Guided Bone Regeneration for Critical Defects: A Histological, Histomorphometric, Immunohistochemical, and Inflammatory Profile Analysis.

The objective of this study was to compare the effectiveness of two porcine collagen membranes of different origin used for guided bone regeneration procedures. Resorbable collagen membrane from porcine dermis (Bio-Gide, Geistlich Pharma AG, Wolhusen, Switzerland) and resorbable collagen membrane from porcine pericardium (Jason, Institut Straumann AG, Peter Merian-Weg, Switzerland) were evaluated; histological, histometric, immunohistochemical, and inflammatory profile analyses were performed. The study was carried out on critical defects created in the calvaria of 72 rats (Rattus norvegicus albinus, Wistar variety) divided into three groups: coagulum group (Co), porcine pericardium group (JS), and porcine collagen group (BG). The defects were filled with clot, over which the membranes were placed. The animals were euthanized 7, 15, 30, and 60 days after surgery. The Shapiro-Wilk test was used to assess data distribution. Analysis of variance (ANOVA) and the Bonferroni multiple comparison test were used to compare the differences across the mean values of the variables. Nonparametric tests, Mann-Whitney and Wilcoxon W, were used for the quantitative analysis of the inflammatory profile. A significance level of 5% (p < 0.05) was adopted with a confidence interval of 95%. SPSS software version 2.0 was used. A total of 1,008 analyses were performed on 288 histological slides. It was noted that both types of collagen membranes used in this study were effective for the guided bone regeneration procedure, with a greater proportion and thickness of bone formation among recipients of the BG (735 points, p = 0.021). This membrane also had greater permeability (62.25). The animals in the JS group, which received the porcine pericardial membrane, showed early and accelerated bone formation from early bone tissue, milder osteopontin and osteocalcin levels, and greater inflammatory reaction (86.4). The collagen membrane from porcine dermis demonstrated a more orderly and physiological repair process, while the porcine pericardial membrane presented a more accelerated repair process that did not remain constant over time.

Association of Human Leukocyte Antigen Genotypes with Severe Acute Respiratory Syndrome Coronavirus 2 Vaccine-Induced Subacute Thyroiditis.

Background: Despite mass vaccination, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccine-induced subacute thyroiditis (SAT) is rarely seen as a complication. The reason why some individuals are susceptible to developing vaccine-induced SAT is not known. SAT develops in genetically predisposed individuals who carry specific human leukocyte antigen (HLA) haplotypes. It is unknown whether specific HLA alleles are associated with SARS-CoV-2 vaccine-induced SAT. Objective: This study compared the HLA profiles of patients with SARS-CoV-2 vaccine-induced SAT to controls, to assess whether there is an association between specific HLA genotypes and development of SAT. The relationship between HLA genotypes and the clinical course of SARS-CoV-2 vaccine-induced SAT was also evaluated. Methods: A case-control study was conducted in a Turkish tertiary care center. Fourteen patients with SARS-CoV-2 vaccine-induced SAT and 100 healthy controls were included. HLA-A, HLA-B, HLA-C, HLA-DQB1, and HLA-DRB1 frequencies were analyzed by next-generation sequencing. Results: The frequencies of HLA-B*35 and HLA-C*04 alleles were significantly higher in SARS-CoV-2 vaccine-induced SAT cohort when compared with controls (HLA-B*35: 13 [93%] vs. 40 [40%], p < 0.001; HLA-C*04: 13 [93%] vs. 43 [43%], p < 0.001, respectively). More severe thyrotoxicosis was seen in patients having HLA-B*35 and HLA-C*04 homozygous alleles (free thyroxine: 4.47 ng/dL [3.77-5.18] vs. 1.41 ng/dL [1.22-2.63], p = 0.048). Inflammation tended to be more severe in homozygous patients (C-reactive protein: 28.2 mg/dL [13.6-42.9] vs. 4.8 [1.2-10.5], p = 0.07). Conclusions: The frequencies of HLA-B*35 and HLA-C*04 alleles were higher in SARS-CoV-2 vaccine-induced SAT compared with controls. Homozygosity for HLA-B*35 and HLA-C*04 was associated with thyrotoxicosis and a greater inflammatory reaction. Our findings should be confirmed in studies of other populations.

In-Hospital Electrical Storm in Acute Myocardial Infarction - Clinical Background and Mechanism of the Electrical Instability.

Recurrent ventricular tachycardia (VT) and fibrillation (VF), the so-called "electrical storm" (ES) occurs at various stages of acute myocardial infarction (AMI), but its incidence, background, and short-term prognosis remain unclear. Methods and Results: A retrospective observational study was performed using the registry database of the Tokyo CCU Network. The individual data of 6,003 patients with AMI during 2011-2012 was corrected. ES was defined as more than 3 episodes of sustained VT/VF during a 24-h period as first documented after hospitalization. ES occurred in 55 patients after admission (0.9%). The ES(+) group had more severe heart failure (Killip class >III), more extensive MI (peak-CK), greater inflammatory reaction (CRP), history of diabetes, and more frequent application of hemodialysis as compared with the ES(-) group (n=5,865). When the ES patients were divided into Early-ES (n=37: ES occurred ≤48 h after the onset of MI) and Late-ES (n=15 >48 h after onset of MI) groups, logistic regression analysis revealed that Early-ES was associated with severity of MI, whereas Late-ES was related to systemic disorders, including inflammation, renal dysfunction, or diabetes. Late-ES was an independent predictor of in-hospital death. In-hospital ES was a rare clinical manifestation of AMI. The features and background of the ES varied as time elapsed after admission for MI.

In vivo evaluation of tissue response to new endodontic sealers

The sealers can be in direct contact with the periapical tissues. Thus, these materials must have appropriate physical and biological properties, providing conditions for repair to occur. Objective: The aim of this study was to evaluate the response of rat subcutaneous tissue to endodontics sealers. Material and methods:Three materials comprised the groups: group I – Zinc Oxide, Eugenol and Iodoform paste, group II – Portland cement with propylene glycol, and group III – MTA Fillapex® (Angelus). These materials were placed in polyethylene tubes and implanted into dorsal connective tissue of Wistar rats for seven and 15 days. The specimens were stained with hematoxylin and eosin and evaluated regarding to inflammatory reaction parameters through a light microscope. The data were compared using Kruskal-Wallis test with significance level of 5%. The intensity of inflammatory response against the sealers was analyzed by two blinded and previously calibrated observers for all experimental periods. Results: The histological evaluation showed that all the materials caused a moderated inflammatory reaction at seven days which decreased with time. A greater inflammatory reaction was observed at seven days in group I. The other specimens had significantly less inflammatory cells when compared to this group. Tubes with MTA Fillapex® presented some giant cells, macrophages and lymphocytes after seven days. At 15 days, the presence of fibroblasts and collagen fibers was observed indicating normal tissue healing. The group II showed similar results to those observed in MTA Fillapex® already at seven days. At 15 days the inflammatory reaction presented was almost absent at the tissue, with many collagen fibers indicating normal tissue healing. Statistical analysis showed a significant statistical difference amongst the group I (seven days) and II (15 days) (p &lt; 0.05). In the other groups no significant statistical differences were observed. Conclusion: MTA Fillapex® and Portland cement with propylene glycol were more biocompatible than the other tested cements.

Rat subcutaneous tissue response to MTA Fillapex® and Portland cement

The aim of this study was to evaluate the response of rat subcutaneous tissue to MTA Fillapex® (Angelus), an experimental root canal filling material based on Portland cement and propylene glycol (PCPG), and a zinc oxide, eugenol and iodoform (ZOEI) paste. These materials were placed in polyethylene tubes and implanted into the dorsal connective tissue of Wistar rats for 7 and 15 days. The specimens were stained with hematoxylin and eosin, and evaluated regarding inflammatory reaction parameters by optical microscopy. The intensity of inflammatory response against the sealers was analyzed by two blinded and previously calibrated examiners for all experimental periods (kappa=0.96). The histological evaluation showed that all materials caused a moderate inflammatory reaction at 7 days, which subsided with time. A greater inflammatory reaction was observed at 7 days in the tubes filled with ZOEI paste. Tubes filled with MTA Fillapex presented some giant cells, macrophages and lymphocytes after 7 days. At 15 days, the presence of fibroblasts and collagen fibers was observed indicating normal tissue healing. The tubes filled with PCPG showed similar results to those observed in MTA Fillapex. At 15 days, the inflammatory reaction was almost absent at the tissue, with several collagen fibers indicating normal tissue healing. Data were analyzed by the nonparametric Kruskal-Wallis test (α=0.05). Statistically significant difference (p<0.05) was found only between PCPG at 15 days and ZOEI at 7 days groups. No significant differences were observed among the other groups/periods (p>0.05). MTA Fillapex and Portland cement added with propylene glycol had greater tissue compatibility than the PCPG paste.

Induction of cell migration and activation in mice by the freshwater sponge Drulia uruguayensis Bonetto &amp; Ezcurra de Drago, 1968 (Porifera: Metaniidae)

Freshwater sponges are abundant in the Amazon region and they have been known to cause dermatitis (acute inflammation) since the beginning of the 20th century. To determine whether additional constituents, besides their body spicules, cause dermatological reactions in humans, an experimental study was developed and carried out using mice and Drulia uruguayensis prepared in three different forms: intact sponges (IS), macerated sponges (MS) or isolated spicules - megascleres (ISM). The cells most commonly involved in inflammatory reactions (mast cells, eosinophils and neutrophils), as well as intraepithelial lymphocytes and degranulated mast cells, were counted so that they could be used as parameters to determine which of the sponge preparations induced the greatest reaction. The effects of the sponge on the skin were then determined by histological analysis. The results obtained showed that IS caused the greatest inflammatory reaction (p = 0.000005), activating mainly mast cells (p = 0.0018). The histopathological analysis revealed a slight loss of continuity of the epidermis when ISM or IS were applied. These findings allow us to conclude that a structurally intact sponge can cause a greater inflammatory reaction in the first contact because of its ability to perforate the skin and allow inflammatory agents to enter. Other proteins present in dried sponge bodies could induce allergic but not toxic responses (in contact with the entire sponge, a large number of pharmacologically inert proteins may be introduced, with a potential allergen).

Evaluation of peritoneal adhesions formation and tissue response to polypropylene - poli (2-hydroxyethyl methacrylate)-(polyHEMA) implant on rats' abdominal wall

To verify if the composit poli (2-hydroxyethyl methacrylate)-PolyHEMA/polypropylene mesh implanted in the female rat's abdominal wall could be suitable for the prevention of peritoneal adhesions, and for the evaluation of the tecidual response produced by this biomaterial. Polypropylene meshes (Group PP, n=20) and polypropylene meshes coated with a layer of poli (2-hydroxyethyl methacrylate)-PolyHEMA (Group PH, n=20) were implanted on the abdominal wall of Wistar female rats. Ten animals from each group were submitted to euthanasia at 15 and 30 days of the postoperative period. The animals from the group PP presented visceral adhesions on the mesh surface, which was not observed in the ones from group PH. At the histopathological examination foreign body response was observed in both groups, whilst there was a greater intensity of inflammatory response in group PH on both moments. The poli (2-hydroxyethyl methacrylate) polyHEMA hydrogel associated to polypropylene mesh reduces visceral adhesion formation in rats, although it may be associated to greater inflammatory reaction.

Middle Ear Packing: Comparison Between Merogel and Gelfoam

Problem Gelfoam has been used for decades in otologic surgery to support grafts and prostheses despite causing fibrosis and adhesions. More biocompatible packing materials could avoid these complications. This study compares Gelfoam with an injectable esterified hyaluronic acid, Merogel, as middle ear packing material after mucosal trauma. Methods A randomized, blinded, controlled study was performed in 17 juvenile guinea pigs. Middle ear surgery with mucosal trauma was performed and middle ears were packed with Merogel or Gelfoam; unpacked contralateral ears were used as controls. Auditory brainstem response (ABR) thresholds were measured in 4 frequencies pre-operatively, and repeated at 1, 2, and 6 weeks postoperatively. Gross analysis measured inflammatory reaction in each group. Statistical analysis was performed using ANOVA followed by post-hoc analysis for ABR thresholds and packing remaining at 6 weeks. Non-prametric tests were used for presence of mucosal inflammation, effusion and tympanic membrane perforation. Results ABR threshold changes from baseline were minor and comparable between the Merogel group and the control group. Threshold change was higher in the Gelfoam group. This difference was seen in each frequency tested at each time interval (all p&lt;0.05). Gross analysis showed 1) Mucosal inflammation higher in the Gelfoam group (p&lt;0.05), 2) Effusions were higher in the Gelfoam group but the difference was not significant (p=0.07), 3) Tympanic membrane perforation was equally rare between groups (p&gt;0.05), 4) Unabsorbed packing was higher in the Gelfoam group (p&lt;0.05); little Merogel was detectable at time of sacrifice. Conclusion Middle ear healing after surgery occurred similarly in the control group and the Merogel group. In contrast, the Gelfoam group demonstrated greater perturbation of hearing and a greater inflammatory reaction. Significance These results support Merogel as an alternative to Gelfoam in middle ear packing after otologic surgery. Support Research grant from Medtronic ENT.

A preliminary study of healing of diode laser versus scalpel incisions in rat oral tissue: a comparison of clinical, histological, and immunohistochemical results

The aim of this preliminary study was to compare wound healing of rat oral tissues after surgical procedure with diode laser or scalpel. Healing was evaluated histologically, immunohistochemically, and by measurement of 2 nitric oxide synthase isoforms (eNOS and iNOS) as intracellular messenger molecules with important immune functions. The instruments were also evaluated for performance and ease of use. Twenty-four standardized incisions were performed in the hard palate of 12 male Wistar rats. Each rat received 2 incisions on the opposite sides of the palate by using a steel scalpel (control group) and a diode laser (808 nm) at a power output of 4 W and 6 W (test group). Histological and immunohistochemical analyses were performed on tissue samples after 7 and 14 days. The expression of eNOS and iNOS was confirmed by RT-PCR (reverse transcriptase-polymerase chain reaction) and Western blot analysis. Scalpel repair was found to be equivalent to or better than laser repair at the intervals measured. Histological analysis showed that incision wound repair after laser surgical procedure was related to parameters and beam characteristics. Diode laser at a power output of 6 W showed the worst results of tissue repair, especially after 7 days. On the contrary, the extent of epithelial damage lateral to the wound edge and the extent of collagen denaturation were near equal with scalpel incision and laser irradiation at 4 W after 14 days. Biochemical analysis of RT-PCR and Western blots also confirmed histological results with a greater concentration of eNOS and iNOS after 7 days of laser surgical procedure. Clinical and histological findings change over time for different treatments. Diode laser tends to produce more pronounced changes than conventional scalpel surgical procedure (due to tissue thermal damage), with corresponding greater inflammatory reaction and delay in tissue organization only at the initial stage. Thus, long-term histology is critical for predicting treatment results. The clinical use of low-level diode laser for tissue welding of oral mucosa should be investigated further, since it appears to be a good alternative to scalpel incision and suture repair.

A preliminary study of healing of superpulsed carbon dioxide laser incisions in the hard palate of monkeys.

Prior studies of laser wound healing using different animal models have shown a delayed tissue response after carbon dioxide (CO2) laser application. This article reports on the preliminary findings of healing of superpulsed CO2 laser and scalpel incisions in the hard palate of monkeys. Twelve parallel incisions using a superpulsed, continuous wave CO2 laser and a scalpel were performed in the hard palate of each of two adult monkeys at 3, 7, and 14 days time schedules. Power levels of 2.0, 4.0, and 6.0 Watts were used for the laser incisions. Wounds were harvested, fixed in 10% formalsaline for at least 48 hours and processed routinely. Each specimen was embedded in paraffin wax at 90 degrees to the surface epithelium and 5 microm thick sections prepared for staining with haematoxylin and eosin, Periodic acid Schiff and Masson-trichrome at a step-serial interval of 100 microm. Sections were evaluated independently. According to the clinical findings we showed a wound closure in all of the wounds (laser and scalpel incisions) at 3, 7, and 14 days of healing. Histologically, we showed that laser incisions at three and seven days demonstrated an increased, power setting-dependent tissue necrosis and marked inflammatory response with minimal organization compared to scalpel incisions. At 14 days both types of incisions exhibited complete wound healing of the epithelium and connective tissue. According to these preliminary results, superpulsed CO2 laser tends to produce more pronounced changes (due to tissue thermal damage) with corresponding greater inflammatory reaction and delay in tissue organization only initially.

Treatment of Oral Cavity and Oropharynx Squamous Cell Carcinoma with Perilymphatic Interleukin-2

We describe the correlations between the clinical and histologic findings in an initial series of 60 patients with T2-4, N0-3, M0 squamous cell carcinoma (SCC) of the oral cavity or oropharynx enrolled in a randomized trial set up to evaluate whether the disease-free interval and survival are extended when perilymphatic injections of recombinant interleukin-2 (rIL-2) are combined with routine surgery and radiotherapy. Twenty-nine patients were operated on only (controls). The other 31 received two daily injections of 2,500 U rIL-2, one near the mastoid process on the same side as the tumor and the other under the chin, for 10 days before surgery, and further injections on the nonoperated-on side on a monthly basis for 1 year starting 4 weeks after surgery (or radiotherapy, where necessary) in an effort to upregulate the immune system and delay recurrence. Their surgical specimens displayed a significantly greater inflammatory reaction, larger areas of necrosis, and more intense sclerosis. The inflammatory tumor infiltration consisted of eosinophils, plasma cells, and CD25+ and human leukocyte antigen (HLA)-DR+ lymphocytes. However, no correlations were apparent with regard to the intensity of necrosis, eosinophil infiltration, and the number of DR+ cells and the clinical outcome. By contrast, the correlation between CD25+ cells and a significantly longer disease-free survival suggests that induction of T-cell reactivity, and perhaps specific immunity, is the only important aspect of rIL-2-induced antitumor reactivity.