Comparative analysis of different loop types for urine culture collection: Implications for quantitative bacterial growth and culture results.

We hypothesized that the loop material and size could affect the results of the culture when compared to the calibrated pipette. A total of 484 urine samples were included in the study, and each sample was plated by using different loop types and the calibrated pipette. The bacterial counts per milliliter were calculated and compared, with a focus on the important cutoff values of 10³ and 104 CFU/ml for further identification. When considering the 10³ CFU/ml as cutoff value, 1 µl and 10 µl plastic loops gave the highest sensitivity (86.8 %), whereas the 10 µl metal loop had the lowest sensitivity (64.2 %). For the 104 CFU/ml cutoff value, 1 µl plastic loop inoculation demonstrated the highest sensitivity (75.9 %), while the 10 µl metal loop provided the lowest sensitivity (26.5 %). These results suggest that the single use plastic loops are functional, sensitive, useful especially for critical sample.

Neutralization of Wild-Type and Alpha SARS-CoV-2 Variant by CoronaVac® Vaccine and Natural Infection- Induced Antibodies.

One of the immune responses desired to be achieved by SARS-CoV-2 vaccination is to create neutralizing antibodies (nAbs), thus preventing the development and spread of infection. The aim of this study was to investigate the seropositivity rate, anti-spike antibody levels, and neutralizing capacity of these antibodies against wild type (WT) and alpha variants in serum samples of individuals who had been naturally infected or vaccinated with CoronaVac®. Total anti-spike antibody levels were determined in all samples. Neutralization assays were performed by the reduction of the cytopathic effect in Vero-E6 cells with infectious WT and alpha SARS-CoV-2 variants. Although both naturally infected and vaccinated individuals were all seropositive for antispike antibodies, 84.8% of the vaccinated group, and 89.3% of the naturally infected group had detectable nAbs. The nAbs titers were significantly higher in the naturally infected group for both WT and alfa variant of the virus as compared to the vaccinated individuals. In this study, it was observed that all individuals became seropositive six weeks after exposure to the vaccine or the virus. Moreover, naturally infected individuals had higher levels of nAbs than those vaccinated. The presence of nAbs against the alpha variant in both naturally infected and vaccinated individuals suggests that these antibodies may also be protective against infections, which may be caused by other variants, such as delta and omicron.

Immune responses in multiple hosts to Nucleocapsid Protein (NP) of Crimean-Congo Hemorrhagic Fever Virus (CCHFV).

In 2019, the World Health Organization declared 3 billion to be at risk of developing Crimean Congo Hemorrhagic Fever (CCHF). The causative agent of this deadly infection is CCHFV. The data related to the biology and immunology of CCHFV are rather scarce. Due to its indispensable roles in the viral life cycle, NP becomes a logical target for detailed viral immunology studies. In this study, humoral immunity to NP was investigated in CCHF survivors, as well as in immunized mice and rabbits. Abundant antibody response against NP was demonstrated both during natural infection in humans and following experimental immunizations in mice and rabbits. Also, cellular immune responses to recombinant NP (rNP) was detected in multispecies. This study represents the most comprehensive investigation on NP as an inducer of both humoral and cellular immunity in multiple hosts and proves that rNP is an excellent candidate warranting further immunological studies specifically on vaccine investigations.

A Current Microbiological Picture of Mycobacterium Isolates from Istanbul, Turkey.

Despite advances in diagnosis and treatment, tuberculosis (TB) continues to be one of the essential health problems throughout the world. Turkey is considered to be endemic for TB. In this study, we analyzed the distribution of Mycobacterium species, compare the diagnostic methods, and susceptibilities to anti-tuberculosis drugs of TB isolates. The aim was to document the current status and to provide a frame of reference for future studies. In this study, 278 Mycobacterium species isolated from 7,480 patients between September 2015 and June 2019 were included. Löwenstein-Jensen medium (LJ) and MGIT 960 were used for the isolation of strains. Susceptibility to 1st-line anti-tuberculosis drugs was determined. Positivity rates in clinical samples were as follows: 1.4% for direct microscopic acid-fast bacilli (AFB) detection, 3.4% for growth on the LJ, and 3.7% for growth on MGIT-960. Two hundred thirty-three isolates were identified as Mycobacterium tuberculosis complex (MTBC) and 45 were non-tuberculous mycobacteria (NTMs). Eleven of the NTMs (24.4%) were Mycobacterium fortuitum group isolates, and eight NTMs (17.7%) were Mycobacterium abscessus complex isolates. A number of patients diagnosed with tuberculosis peaked twice between the ages of 20-31 and 60-71. A hundred and eighty-two MTBC isolates (78.1%) were susceptible to all 1st-line anti-tuberculosis drugs, while 51 isolates (21.9%) were resistant to at least one drug tested. The multidrug-resistant tuberculosis rate was 13.7% among resistant strains and 3% in all strains. The liquid cultures were better for detection of both MTBC and NTMs isolates. The data demonstrate that MTBC continues to be challenge for this country and indicates the need for continued surveillance and full-spectrum services of mycobacteriology laboratory and infectious diseases.Despite advances in diagnosis and treatment, tuberculosis (TB) continues to be one of the essential health problems throughout the world. Turkey is considered to be endemic for TB. In this study, we analyzed the distribution of Mycobacterium species, compare the diagnostic methods, and susceptibilities to anti-tuberculosis drugs of TB isolates. The aim was to document the current status and to provide a frame of reference for future studies. In this study, 278 Mycobacterium species isolated from 7,480 patients between September 2015 and June 2019 were included. Löwenstein-Jensen medium (LJ) and MGIT 960 were used for the isolation of strains. Susceptibility to 1st-line anti-tuberculosis drugs was determined. Positivity rates in clinical samples were as follows: 1.4% for direct microscopic acid-fast bacilli (AFB) detection, 3.4% for growth on the LJ, and 3.7% for growth on MGIT-960. Two hundred thirty-three isolates were identified as Mycobacterium tuberculosis complex (MTBC) and 45 were non-tuberculous mycobacteria (NTMs). Eleven of the NTMs (24.4%) were Mycobacterium fortuitum group isolates, and eight NTMs (17.7%) were Mycobacterium abscessus complex isolates. A number of patients diagnosed with tuberculosis peaked twice between the ages of 20­31 and 60­71. A hundred and eighty-two MTBC isolates (78.1%) were susceptible to all 1st-line anti-tuberculosis drugs, while 51 isolates (21.9%) were resistant to at least one drug tested. The multidrug-resistant tuberculosis rate was 13.7% among resistant strains and 3% in all strains. The liquid cultures were better for detection of both MTBC and NTMs isolates. The data demonstrate that MTBC continues to be challenge for this country and indicates the need for continued surveillance and full-spectrum services of mycobacteriology laboratory and infectious diseases.

Distribution of ß-lactamase genes among carbapenem-resistant Klebsiella pneumoniae strains isolated from patients in Turkey.

BACKGROUND: The emergence of carbapenem-resistant Klebsiella pneumoniae poses a serious problem to antibiotic management. We investigated the ß-lactamases in a group of carbapenem-resistant K. pneumoniae clinical isolates from Turkey. METHODS: Thirty-seven strains of K. pneumoniae isolated from various clinical specimens were analyzed by antimicrobial susceptibility testing, PCR for the detection of ß-lactamase genes, DNA sequencing, and repetitive extragenic palindronic (REP)-PCR analysis. RESULTS: All 37 isolates were resistant to ampicillin, ampicillin/sulbactam, piperacillin, piperacillin/tazobactam, ceftazidime, cefoperazone/sulbactam, cefepime, imipenem, and meropenem. The lowest resistance rates were observed for colistin (2.7%), tigecycline (11%), and amikacin (19%). According to PCR and sequencing results, 98% (36/37) of strains carried at least one carbapenemase gene, with 32 (86%) carrying OXA-48 and 7 (19%) carrying NDM-1. No other carbapenemase genes were identified. All strains carried a CTX-M-2-like ß-lactamase, and some carried SHV- (97%), TEM- (9%), and CTX-M-1-like (62%) ß-lactamases. Sequence analysis of bla(TEM) genes identified a bla(TEM-166) with an amino acid change at position 53 (Arg53Gly) from bla(TEM-1b), the first report of a mutation in this region. REP-PCR analysis revealed that there were seven different clonal groups, and temporo-spatial links were identified within these groups. CONCLUSIONS: Combinations of ß-lactamases were found in all strains, with the most common being OXA-48, SHV, TEM, and CTX-M-type (76% of strains). We have reported, for the first time, a high prevalence of the NDM-1 (19%) carbapenemase in carbapenem-resistant K. pneumoniae from Turkey. These enzymes often co-exist with other ß-lactamases, such as TEM, SHV, and CTX-M ß-lactamases.

[Intestinal strongyloidiasis in a psoriasis patient with diabetes]. / Psöriyazis ve Diyabetes Mellitus Tanili Hastada Intestinal Strongyloidosis.

This case study underlined the importance of parasitological examination before starting immunosuppressive treatment since a heavy burden of strongyloidiasis could lead to fatal infections. It represents the first strongyloidiasis from a patient with psoriasis and diabetes mellitus in this country. In the case, 59 years old female subject had psoriasis for six years and during the treatment with topical corticosteroid and anti-psorial medication, psoriatic lesions flared up. The patient had constipation and foul smelling stool complaints. Blood tests showed an increase in eosinophil and a decrease of vitamin B12 level. Stool examination indicated the presence of abundant amount of S. stercoralis larvae. The patient was given albendazole for two weeks. After treatment, the symptoms decreased and S. stercoralis larvae were not detected in stool. In this case, it was emphasized that the clinicians planning immunosuppressive regimens should bear in mind that parasitic examination could be present in the subjects.

Influence of some substances on bacterial translocation in the rat.

An experimental study was planned to determine the effect of zinc, levamisole, misoprostol (prostaglandin(1) analog), and melatonin on the bacterial translocation (BT) that develops in rats after major resection of the liver. To this aim, six groups were formed, each consisting of six rats. Except for the control and sham groups, zinc solution 1 ml/day, (prepared in a way to include zinc sulfate equivalent of 5 mg pure zinc/ml) was given to the zinc groups, levamisole 25 mg/kg/day to the levamisole group, misoprostol 200 mg/kg/day to the misoprostol group, and melatonin 20 mg/kg/day to the melatonin group for 3 days before the operation. After the preoperative administration of 10(10) colony-forming units of Escherichia coli to the experimental groups, the abdomen was opened in the sham group, and only the connections around the liver were cut. In the test groups a 70% liver resection was undertaken. Laparotomy was carried out on all the rats 24 hours after the operation; blood samples were obtained for polymerase chain reaction (PCR) analysis and tissue samples from the terminal ileum for histopathologic examination. PCR results for BT were positive for the control and sham groups, with the difference between these two groups not significant (p > 0.05). A statistically significant decrease was found in the BT of all the treatment groups compared to the control group (p <0.05). The histopathologic examination of terminal ileum in the control group revealed that the inflammatory infiltration was significantly less than that in the other groups (p <0.05).

[Cloning and expression of the hepatitis B virus HBcAg gene in eukaryotic cells]. / Hepatit B virusu HBcAg geninin klonlanmasi ve ökaryotik hucrelerde ekspresyonu.

In the present study, cloning of hepatitis B core antigen (HBcAg) gene and expression of the gene in eukaryotic cells have been reported. For this purpose, initially, HBcAg gene which was previously cloned into pUC19 plasmid, was excised by EcoRI ve HindIII from this plasmid and inserted into an eukaryotic expression vector pcDNA3. Afterwards, the resulting recombinant plasmid (pcDNA-HBc) was transfected into Vero cells, and the stable transfected cells (Vero-HBc) were selected in geneticin containing culture medium. The presence of HBcAg gene in Vero-HBc cells were confirmed by polymerase chain reaction and, the expression of HBcAg gene by Vero-HBc cells were tested in Western Immunoblotting assay. As a result, a 21 kDa protein reacting with anti-HBc antibodies which Vero-HBc cells indeed expressed, were detected at the end of this assay.