Occurrence of Anti-Rickettsia spp. Antibodies in Hospitalized Patients with Undifferentiated Febrile Illness in the Southern Region of Kazakhstan

Undifferentiated febrile illness still represents a demanding medical problem all over the world, but primarily in low- and middle-income countries. Scientific and clinical investigations related to undifferentiated febrile illness and rickettsial diseases in Kazakhstan are lacking. This study reflects the investigation of antibodies against spotted fever group (SFG) and typhus group (TG) rickettsiae in patients with undifferentiated febrile illness in the southern region of Kazakhstan (Almaty and Kyzylorda oblasts). Paired serum samples were gathered from 13 hospitals in these two oblasts and explored for the presence of IgM and IgG antibodies against typhus group and IgG antibodies against spotted fever group rickettsiae using ELISA. Patient's questionnaires were statistically analyzed. In total, 802 inpatients from Almaty (N = 9) and Kyzylorda (N = 4) hospitals were included in this research. Based on ELISA results, 250 patients out of 802 (31.2%) from both oblasts had IgG antibodies against SFG rickettsiae. Results from 11 (1.4%) patients indicated acute infection with tick-borne rickettsiosis. Regarding TG rickettsiae (R. typhi), a past infection was detected in 248 (30.9%) febrile patients and acute infection in 22 (2.7%) patients in the two selected oblasts. The data indicated that SFG and TG rickettsioses are present in Kazakhstan. Kazakh physicians should be aware of these emerging diseases in both investigated oblasts because the occurrence of these diseases is not suspected during day-to-day clinical practice. The identification of rickettsial pathogens and implementation of modern laboratory methods for the diagnostics of rickettsioses are in need throughout Kazakhstan.

MO480FGF-23 AND LOW BIRTH WEIGHT: IS THERE ANY ASSOCIATION?

Background and Aims

According to Barker’s theory and Brenner’s hypothesis, persons were born with low birth weight (LBW) have a higher risk of CKD due to low nephron number. Also, it is well known that mineral-bone disorder (MBD) is one of the most serious complications of CKD. Views on the pathogenesis of CKD-MBD have changed considerably since Fibroblast growth factor 23 (FGF-23) was discovered. It is thought that FGF-23 increases as the nephron mass reduces. Therefore, we aimed to determine if there is an association between LBW and FGF-23.

Method

We conducted a cross-sectional study on 56 children with CKD stages 1-4. There were approximately equal numbers of participants in each stage. The mean age was 8.9 ±4.9 years old. We measured the concentration of FGF-23 (C-terminal) in serum by a sandwich enzyme-linked immunosorbent assay (ELISA) kit (Biomedica Medizinprodukte GmbH, Austria). The exclusion criteria: tubulopathy, active inflammatory, infectious, oncological and bone diseases, renal transplant, as well as taking steroids, calcium, and vitamin D. The informed consent was obtained from the parents. The study was conducted in accordance with the Declaration of Helsinki and approved by the Local Ethical Committee. FGF-23 concentration more than 1.5 pmol/l was considered as abnormal. Statistical analysis was performed using GraphPad Prism 9.0.0 (San Diego, USA)

Results

Mineral-bone disorder was diagnosed as CKD complication in 20 (35.7%) children. LBW was revealed in 14 (25%) patients. The median (IQR) eGFR among patients with normal birth weight was 65.23 (31.23-84.73) ml/min/1.73m2, among LBW – 68.93 (24.59-98.9) ml/min/1.73m2, so there were no differences in kidney function between the two groups (p=0.64). The median (IQR) level of serum FGF-23 in patients with normal birth weight was 1.75 (0.68- 2.5) pmol/l, in LBW children was 1.85 (0.78 -3.1) pmol/l. Analysis of serum level of FGF-23 in relation to weight at birth revealed no statistical differences in patients with LBW and those with normal birth weight (p=0.719), and the Spearman rank correlation was insignificant as well (r=-0.08, p=0.560).

Conclusion

FGF-23 is an important biomarker of CKD-MBD. FGF-23 does not depend on the birth weight although LBW is considered as a risk factor for CKD. However, further investigations and studies in this area are needed to make the right conclusions regarding the association between this bone biomarker and birth weight.

Gas Chromatography-Mass Spectrometry Profiling of Volatile Metabolites Produced by Some Bacillus spp. and Evaluation of Their Antibacterial and Antibiotic Activities

Bacillus species produce different classes of antimicrobial and antioxidant substances: peptides or proteins with different structural compositions and molecular masses and a broad range of volatile organic compounds (VOCs), some of which may serve as biomarkers for microorganism identification. The aim of this study is the identification of biologically active compounds synthesized by five Bacillus species using gas chromatography coupled to mass spectrometry (GC-MS). The current study profoundly enhances the knowledge of antibacterial and antioxidant metabolites ensuring the unambiguous identification of VOCs produced by some Bacillus species, which were isolated from vegetable samples of potato, carrot, and tomato. Phylogenetic and biochemical studies were used to identify the bacterial isolates after culturing. Phylogenetic analysis proved that five bacterial isolates BSS12, BSS13, BSS16, BSS21, and BSS25 showed 99% nucleotide sequence similarities with Bacillus safensis AS-08, Bacillus cereus WAB2133, Bacillus acidiproducens NiuFun, Bacillus toyonesis FORT 102, and Bacillus thuringiensis F3, respectively. The crude extract was prepared from bacterial isolates to assess the antibiotic resistance potency and the antimicrobial potential against various targeted multidrug-resistant strains, including yeast strains such as Candida albicans, Candida krusei, and bacterial strains of Enterococcus hirae, Escherichia coli, Klebsiella aerogenes, Klebsiella pneumoniae, Staphylococcus aureus, Staphylococcus epidermidis, Streptococcus group B, Streptococcus mutans, Shigella sonnei, Salmonella enteritidis, Serratia marcescens, Pseudomonas aeruginosa, and Proteus vulgaris. GC-MS analysis of bacterial strains found that VOCs from Bacillus species come in a variety of chemical forms, such as ketones, alcohols, terpenoids, alkenes, etc. Overall, 69 volatile organic compounds were identified from five Bacillus species, and all five were found to share different chemical classes of volatile organic components, which have a variety of pharmacological applications. However, eight antibacterial compounds with different concentrations were commonly found in all five species: acetoin, acetic acid, butanoic acid, 2-methyl-, oxime-, methoxy-phenyl, phenol, 1,2-benzenedicarboxylic acid, bis(2-methylpropyl) ester, nonanoic acid, and hexadecanoic acid, methyl. The present study has demonstrated that bacterial isolates BSS25, BSS21, and BSS16 display potent inhibitory effects against Candida albicans, while BSS25, BSS21, and BSS13 exhibit the ability to restrain the growth and activity of Candida krusei. Notably, BSS25 and BSS21 are the only isolates that demonstrate substantial inhibitory activity against Klebsiella aerogenes. This disparity in inhibitory effects could be attributed to the higher concentrations of acetoin in BSS25 and BSS21, whereas BSS16 and BSS13 have relatively elevated levels of butanoic acid, 2-methyl-. Certainly, the presence of acetoin and butanoic acid, 2-methyl-, contributes to the enhanced antibacterial potential of these bacterial strains, in conjunction with other organic volatile compounds and peptides, among other factors. The biology and physiology of Bacillus can be better understood using these results, which can also be used to create novel biotechnological procedures and applications. Moreover, because of its exceptional ability to synthesize and produce a variety of different antibacterial compounds, Bacillus species can serve as natural and universal carriers for antibiotic compounds in the form of probiotic cultures and strains to fight different pathogens, including mycobacteria.