Generalized Modules for Membrane Antigens as Carrier for Polysaccharides: Impact of Sugar Length, Density, and Attachment Site on the Immune Response Elicited in Animal Models

Nanoparticle systems are being explored for the display of carbohydrate antigens, characterized by multimeric presentation of glycan epitopes and special chemico-physical properties of nano-sized particles. Among them, outer membrane vesicles (OMVs) are receiving great attention, combining antigen presentation with the immunopotentiator effect of the Toll-like receptor agonists naturally present on these systems. In this context, we are testing Generalized Modules for Membrane Antigens (GMMA), OMVs naturally released from Gram-negative bacteria mutated to increase blebbing, as carrier for polysaccharides. Here, we investigated the impact of saccharide length, density, and attachment site on the immune response elicited by GMMA in animal models, using a variety of structurally diverse polysaccharides from different pathogens (i.e., Neisseria meningitidis serogroup A and C, Haemophilus influenzae type b, and streptococcus Group A Carbohydrate and Salmonella Typhi Vi). Anti-polysaccharide immune response was not affected by the number of saccharides per GMMA particle. However, lower saccharide loading can better preserve the immunogenicity of GMMA as antigen. In contrast, saccharide length needs to be optimized for each specific antigen. Interestingly, GMMA conjugates induced strong functional immune response even when the polysaccharides were linked to sugars on GMMA. We also verified that GMMA conjugates elicit a T-dependent humoral immune response to polysaccharides that is strictly dependent on the nature of the polysaccharide. The results obtained are important to design novel glycoconjugate vaccines using GMMA as carrier and support the development of multicomponent glycoconjugate vaccines where GMMA can play the dual role of carrier and antigen. In addition, this work provides significant insights into the mechanism of action of glycoconjugates.

Karakteristik Pasien Tonsilitis Pada Anak Usia 5-12 Tahun di RSPBA Bandar Lampung Tahun 2020

Tonsillitis is a disease that is often experienced by a person, especially often occurs in children. Based on a survey from the Indonesian Ministry of Health in 2012, the incidence of tonsillitis in Indonesia reached around 23%. Acute tonsillitis that is not properly treated can cause chronic tonsillitis, therefore it is important to know the characteristics of tonsillitis symptoms in order not to develop into chronic tonsillitis. Tonsillitis is an inflammation of the tonsils caused by infection with the Streptococcus group of bacteria or viruses which can be acute or chronic. Symptoms that often appear in tonsillitis are sore throat, difficulty swallowing and when it reaches chronic it can block the respiratory tract. The purpose of this study was to determine the characteristics of tonsillitis patients in children aged 5-12 years at Rspba Bandar Lampung in 2020. The research method in this study was cross-sectional. It is known that the results of the study of tonsillitis patients in children, the most common symptom of which was pain during swallowing (40.5%), tonsillitis patients in children were often found in T2-T2 sizes (37.8%), tonsillitis patients in children were often experienced. by men (71.1%). tonsillitis patients in children are often experienced by ages 7-8 years (48.6%), the incidence of tonsillitis cases is 8.34%, the prevalence of tonsillitis cases in children aged 5-12 years is 41.1%, in children aged 5 -12 years have a lot of chronic tonsillitis. The characteristics found in tonsillitis patients aged 5-12 years, namely swallowing pain, widening of the T2-T2 tonsil size, mostly experienced by men and often occurs at 7-8 years of age, the incidence is 8.34%, prevalence in children. age 5-12 years as much as 41.1% and many children have chronic tonsillitis.

The state of cellular immunity of patients with tonsillitis and infected with herpes virus type 6

Currently, the incidence of tonsillitis in children is very common and represents a serious medical and social problem. In young children, viral tonsillitis predominates, while bacterial tonsillitis is more common between the ages of 5–15. The frequency of registration of infection with viruses of the herpes group, including the human herpes virus (HHV) type 6, is increasing. The healing processes in infectious pathology are primarily due to the balanced work of the cellular and humoral links of the body’s immune response, the state of which can be influenced by concomitant infection with herpes viruses. The aim of the work was to study the cellular immune response of children with tonsillitis infected with HHV-6 type. The study of the influence of HHV-6 infection on the state of the cellular component of the immune response in 74 children with tonsillitis in the acute period and in the period of convalescence was carried out. All patients were diagnosed with a moderate form of tonsillitis; the etiological factor was hemolytic streptococcus group A. It was revealed that in children with mono-infection at the onset of the disease, there is a moderate response of cellular immunity (t = 2.76), while the presence of HHV-6 infection leads to more pronounced changes in the parameters of CD lymphocytes (t = 4.06). We found a significant increase in the content of CD16+-lymphocytes in tonsillitis of streptococcal etiology, but the maximum growth was recorded in patients with mono-infection (p < 0.05). By the time of convalescence, complete recovery of T-lymphocytes in infected HHV-6 patients does not occur. The degree of deviation from the standard for the entire complex of CD-lymphocytes during the period of convalescence was more pronounced in patients with co-infection (t = 2.83). The obtained data indicate the suppression of the cellular component of the immune response in patients with tonsillitis against the background of HHV-6 infection, which requires a differentiated approach to treatment and medical supervision of such patients.

Clinical and paraclinical markers of inflammatory activity in acute tonsilopharyngitis in children

Purpose — to study clinical and paraclinical markers of inflammatory activity in acute non-streptococcal and streptococcal tonsillopharyngitis in children to address rational treatment tactics. Materials and methods. To achieve this goal, a comprehensive examination of 102 children with acute tonsillopharyngitis, which was divided into two clinical groups depending on the isolation of beta-hemolytic streptococcus group A during a culture of smears from the mucosa of the tonsils/pharynx. The first (I) clinical group included 68 patients in whom bacteriological examination did not reveal BGSA — GTP of non-streptococcal etiology (nGTP). And 34 children in whom the streptococcal etiology of the disease was determined formed the second (II) clinical group — streptococcal acute tonsillopharyngitis (cGTP). Results. The presence of a subfebrile body temperature in the child increased its post-test probability by 27.4%, and higher fever figures reduced the probability of non-streptococcal GTP by only 4.3%. The absence of symptoms of intoxication syndrome in children with a high degree of specificity — 91.4% confirms the non-streptococcal nature of the disease. Expressive layers on the tonsils are more characteristic of streptococcal GTP, and the assessment of their severity <3 points was much more common in patients with non-streptococcal disease. When using the determination of the content of C-reactive protein <50.0 mg/l in the venous blood of children as a test, allows you to verify the non-streptococcal nature of acute tonsillopharyngitis with a fairly high sensitivity — 73.5% (95% CI 63.7–81.8), however, low specificity — 35.3% (95% CI 26.0–45.5). Conclusions. Indicators of local inflammation and clinical manifestations of the general inflammatory reaction were less pronounced in patients with non-streptococcal GTP. Indicators of C-reactive protein <50.0 mg/l in venous blood with high sensitivity (73.5%; 95% CI 63.7–81.8) and relative risk 1.2 (95% CI 1.0–1.5) probably testified in favor of the nonstreptococcal nature of acute tonsillopharyngitis. The research was carried out in accordance with the principles of the Helsinki Declaration. The study protocol was approved by the Local Ethics Committee of these Institutes. The informed consent of the patient was obtained for conducting the studies. No conflict of interest was declared by the authors. Key words: acute tonsillopharyngitis, children, clinic, C-reactive protein.

The role of remnant bone microbiological cultures in managing diabetic foot osteomyelitis

Aim: Effective treatment of diabetic foot osteomyelitis can reduce the risk of major amputations. Our primary aim was to compare the yield in cultures from the proximal and distal segments of bone excised intraoperatively and the impact on antibiotic choice and duration.Methods: Patients with a confirmed diagnosis of osteomyelitis on bone culture results, where both proximal and distal bone segment samples had been collected, were retrospectively reviewed. Microbiological data were examined to identify true pathogens and studied against antimicrobial choice and duration of prescribing.Results: A total of 47 forefoot amputation cases were studied. In 89% of cases, definite or likely pathogens were isolated from the deep tissues cultured. Definite pathogens (Staphylococcus aureus, Group B streptococcus, Group G streptococcus and Streptococcus anginosus) were identified in 32% of cases; in 73% of these, definite pathogens were grown in both the proximal and distal bone segments.Conclusion: Sampling of remnant bone culture can help in reducing the duration of antibiotic treatment in patients (27% of cases in our series) as it is challenging to correctly estimate intraoperatively whether clear surgical margins have been adequately achieved when resecting infected bone.

Long-Term Effect of Silicone Oil Tamponade for Postoperative and Posttraumatic Bacterial Endophthalmitis

Purpose. To compare clinical features and microbial profiles, treatment outcomes, and prognostic factors of the eyes between postoperative and posttraumatic bacterial endophthalmitis after pars plana vitrectomy (PPV) with silicone oil (SO) tamponade. Methods. Overall, 57 eyes of 57 patients who diagnosed exogenous bacterial endophthalmitis and underwent PPV with SO tamponade between 2000 and 2019 were reviewed. Causative microorganisms, culture positivity, change of mean best-corrected visual acuity (BCVA), and course of treatment were investigated between postoperative and posttraumatic groups, and relevant factors were analyzed according to the final BCVA. Results. The mean BCVA change was not significantly different between groups. The positive rate of microorganisms was significantly higher in the postoperative group. The mean time to surgery over 48 hours, initial BCVA worse than hand motion, and additional surgery after initial vitrectomy were correlated with poor final BCVA worse than 20/200. There was significantly achieved final BCVA 20/200 or better in the Staphylococcus and Streptococcus group than the Enterococcus and Pseudomonas group. Conclusion. PPV with SO tamponade may be an effective surgical treatment strategy for exogenous bacterial endophthalmitis. Final visual outcomes were not significantly different between postoperative and posttraumatic groups, and the mean time to surgery, initial visual acuity, additional surgery, and type of microorganism are significantly related to visual prognosis.

Influence of ozone generated by pulsed alternating electric current on the viability of representatives of oral microflora involved in the development of prosthetic stomatitis

Topicality. When using removable dentures, in 84.26±1.19 % of cases patients have various changes in the mucous membrane of the prosthetic bed with pronounced changes in microbial ecology which are exacerbated by poor oral hygiene and removable dentures. Ozone therapy is a new and promising area of treatment of microbial lesions of the oral mucosa. It has antiseptic, anti-inflammatory, analgesic, immunomodulatory effects and promotes activation of intracellular metabolism, improvement of rheological properties and microcirculation of blood; it also strengthens reparative ability of the injured tissues. The aim of the study is to evaluate the in vitro effect of ozone generated by the device for use in dental practice on the survival of the representatives of aerobic and facultative anaerobic microflora of the oral cavity, which are important in the development of prosthetic stomatitis. Materials and methods of research. In vitro experiments helped to study the effect of ozone generated by pulsed alternating electric current (Ozone DTA device for use in dental practice) on the survival of the representatives of aerobic and facultative anaerobic microflora of the oral cavity, which may be potential factors in inflammatory processes in prosthetic bed tissues and the development of prosthetic stomatitis. The results were processed by the method of variation statistics and two-way analysis of variance ANOVA (MS Excel 2003). Results. A direct dependence of the influence of the survival level of S. aureus in suspension on the ozone generation capacity and the time of exposure to ozone was established. Different types of oral microorganisms differ in their sensitivity to ozone. Cultures of S. epidermidis, β-hemolytic Streptococcus group G, α-hemolytic streptococci S. sanguinis and S. oralis, yeast-like fungi Candida tropicalis are characterized by relatively higher sensitivity to the generated ozone. Conclusion. The obtained experimental results microbiologically substantiate the possibility and expediency of using ozone therapy to prevent the occurrence and treatment of prosthetic stomatitis. Based on the performed experiments, the optimal mode of ozone therapy with the Ozone DTA device was established to ensure the antimicrobial effect at the level of 98.8–100%. Key words: ozone, microorganisms, antimicrobial action, oral cavity.

The rate of asymptomatic throat carriage of Streptococcus pyogenes and its associated risk factors among Kabul University students

Streptococcus pyogenes (S. pyogenes) is the main agent of acute pharyngitis and skin infections that may result in the late complications of glomerulonephritis and rheumatic fever. Infection with streptococcus group A is a global health problem, which is most common in children and adults. This study was conducted to investigate the rate of S. pyogenes throat carriers and its main risk factors among healthy students of Kabul university. In the present study pharyngeal swabs of 260, [155 (59.6%) were male and 105 (40.4%) were female] asymptomatic university students aged between 19-30 years, were collected and immediately transported to the laboratory for detection of S. pyogenes following standard microbiological procedures. Production of beta hemolytic colonies on blood agar, sensitivity to bacitracin antibiotic, gram stain positivity, catalase negativity test and streptococcal grouping latex kit (ProlexTM) tests were used to identify and differentiate S. pyogenes from other streptococcus spp. Statistical analysis of data was performed using SPSS 21, Chi-square and Logistic regression tests were applied for the categorical data analysis. A P value equal to or less than 0.05 was considered statistically significant. Totally 61 (23.5%) beta hemolytic streptococci were isolated from 260 samples. Among 61 beta hemolytic isolates, 44 (16.9%) were identified as S. pyogenes. The colonization rate of S. pyogenes was higher in male 25 (56.8%) than female 19 (43.2%), which was not statistically significant (p=0.678). Age, residence of the students at hostel and shared utensil use were not statistically significant (p=0.088, p= 0.449, p=0.241 respectively), but the number of children in the family was an important risk factor. People with 1-3 children had a 23-fold higher risk (p˂0.05), and people with 4-6 children had a 27-fold higher risk of carrying S. pyogenes, than those who did not had any children (p˂0.05). In the present study the asymptomatic throat carriage rate of S. pyogenes among Kabul University students, was high. Among all risk factors the number of children in the family was significantly associated with S. pyogenes throat carriage.

Diagnostics of Streptococcal Infection by Emergency Department Doctors: First Experience of Application of the «Streptatest»

The effectiveness of the treatment of acute tonsillitis directly depends on the etiological diagnosis and adherence to the principles of rational etiotropic antibiotic therapy. Currently, streptococcal genesis of inflammation is considered as the only indication for the appointment of systemic antibiotic therapy. The article presents the results of clinical and statistical analysis of calls to patients with acute tonsillitis and express diagnostics of streptococcal infection using «Streptatest». For the period from 30.07.2018 until 30.11.2018 Doctors of the emergency department teams for adults and children performed express diagnostics of group A β-hemolytic streptococcus in 252 patients with acute tonsillitis complaining of «sore throat», whose age ranged from 3 to 44 years. This rapid diagnostic system «Streptatest», based on the method of immunochromatographic analysis, made it possible to identify as early as possible in 117 (46.4%) patients β-hemolytic streptococcus group A and promptly prescribe etiotropic antibiotic therapy to them. The second group consisted of 135 (53.6%) patients with a negative result of the «Streptatest» rapid test. In the group with a positive result of the express test, the main part was made up of children of preschool and school age — 92 (78.6%) patients. In 114 (97.5%) patients with diagnosed group A β-hemolytic streptococcus, clinical symptoms according to the McIsaас modified Centor scale were rated from 3 to 5 points. Early etiological verification of acute tonsillitis made it possible to follow the strategy of preventing the sp read of antimicrobial resistance and reducing the resistance of microorganisms to antibacterial drugs.