Sinovac is an inactive vaccine produced against Coronavirus Disease 2019 (COVID‐19) for almost a year. No sufficient information is available concerning pro‐vaccine immunogenicity. We investigated the efficacy of antibody response following vaccination of SARS‐CoV‐2‐infected and noninfected healthcare workers by a two‐dose inactive vaccine against COVID‐19. The immunogenicity acquired on the 27th day and 42nd day after the first dose of vaccine (corresponding to Day 14 after the second dose) were compared by the demographics, immunosuppression, comorbidities, postvaccination reaction, and IgG levels of 120 subjects. The overall rate of second postvaccine seropositivity was 97.5% (n = 117) of all individuals, and 44 of these were seropositive after the first dose. The percentage of having a previous COVID‐19 (59.1%) among seropositive individuals before 2nd vaccination was significantly higher than those of seropositive individuals (10.96%) after second vaccination (p < 0.0001). In our study, 35 healthcare workers stated that they had previously had a COVID‐19 infection. Anti‐SARS‐CoV‐2 antibody responses in people infected with SARS‐CoV‐2 follow a classical pattern, with a rapid increase within the first 3 weeks after the appearance of symptoms. Although the titers decreased thereafter, the ability to detect anti‐SARS‐CoV‐2 IgG antibodies supports the view that the majority of subjects previously screened as positive for virus remain intact with confirmed neutralizing activity for up to 6 months.

Aim: Previous limited studies have indicated that pro-inflammatory cytokines are elevated in patients with essential tremor (ET). This elevation could lead to a more pronounced inflammatory response in these patients. Thus, this study aimed to investigate the relationship between leukocyte-based inflammatory indices and ET. Material and Methods: In this retrospective study, 103 patients diagnosed with ET between January 2021 and December 2023 were included, along with 103 healthy individuals who were matched by age and gender, participated in check-up programs, and had no other comorbidities. To evaluate tremor severity, the Fahn-Tolosa-Marin (FTM) tremor rating scale was utilized. The leukocyte-based inflammatory indices were calculated as follows: NLR= neutrophils / lymphocytes, PLR = platelets / lymphocytes, systemic immune-inflammation index (SII) = platelets × neutrophils / lymphocytes, and systemic inflammatory response index (SIRI) = neutrophils × monocytes / lymphocytes. Results: The ET group exhibited higher levels of leukocytes, their subtypes, CRP and leukocyte-based inflammatory indices compared to the control group. Increased CRP (OR= 3.71, p < 0.001) and SIRI (OR= 11.73, p < 0.001) levels were independent predictors of ET. In predicting ET. SIRI exhibited superior diagnostic performance compared to other inflammatory parameters. The threshold for SIRI levels was set at 7 and above, with a sensitivity of 85.4% and a specificity of 82.5%. There was a positive correlation between SIRI and FTM scores. Conclusion: Among the leukocyte-based inflammation indices, SIRI demonstrated superior diagnostic performance in predicting ET and was associated with higher tremor severity. This suggests that inflammation may play a potential role in the pathophysiology of ET.

Objective: The objective of this study was to evaluate the demographic, clinical, laboratory, and microbiological features of ventriculoperitoneal shunt (VPS) infections through a 13-year retrospective study. VPS bacterial agents and their antibiotic susceptibility were also investigated through the occurrence of single VPS (SVPS) and recurrent VPS (RVPS) infections. Methods: This study included 110 patients with SVPS infections and 55 patients with RVPS infections. Results: In patients who developed multiple infections, Gram-negative organisms were found to be the most predominant (60%, 54/90). The resistance rates were 85.2% for third-generation cephalosporins (3GCs), 83.3% for piperacillin–tazobactam, and 10.4% for carbapenem. Of the patients in the SVPS infection group, 49% were treated with combinations with carbapenem; of the patients in the RVPS infection group, 84.4% were treated in the same way. Central nervous system (CNS) tuberculosis as the etiology of hydrocephalus; short duration of antibiotics used for treatment; high cerebrospinal fluid (CSF) protein and blood C-reactive protein (CRP) levels; and prolonged use of prophylactic antibiotics were found to be related to an increased rate of recurrent infection occurrence. A two-stage shunt change approach decreased the risk of recurrent infections. Conclusions: Based on the findings of our study, it is essential to closely monitor patients with independent risk factors for RVPS infection development, due to the high rates of resistant Gram-negative bacterial growth and the initiation of empirical antimicrobial treatment with glycopeptide plus carbapenem. Certain treatment options, such as 3GCs plus glycopeptide, should be revised based on clinical progress and microbiological culture results.

Background: Botulinum toxin type A (BoNT-A) is an established preventive therapy for chronic migraine (CM), yet the accompanying neurochemical changes remain incompletely characterized. Objective: To evaluate the effects of BoNT-A on plasma substance P (SP), γ-aminobutyric acid (GABA), glutamate, glutamine, and 5-hydroxytryptamine (5-HT), and on urinary 5-HT, and to explore relationships with clinical outcomes. Methods: In this prospective study, plasma neurotransmitters were analyzed in CM patients (n = 31) at baseline and one month after BoNT-A (155 U; PREEMPT protocol) and in healthy controls (n = 30). Plasma SP was measured using enzyme-linked immunosorbent assay (ELISA); plasma GABA, glutamate, and glutamine were quantified via liquid chromatography–tandem mass spectrometry (LC–MS/MS) with isotopically labeled internal standards; plasma and urinary 5-HT were determined by high-performance liquid chromatography (HPLC). Clinical outcomes included monthly headache frequency, Visual Analog Scale (VAS), and Migraine Disability Assessment (MIDAS). Statistical analyses applied appropriate parametric or non-parametric tests with p < 0.05 considered significant. Results: One month post-BoNT-A, headache frequency, MIDAS, and VAS were significantly reduced (all p < 0.001). SP levels were significantly higher after BoNT-A than at baseline and versus controls. Plasma 5-HT increased post-BoNT-A, while urinary 5-HT decreased. Plasma GABA was elevated in patients versus controls without statistical significance. Glutamine was significantly higher before treatment, whereas the Glu/Gln ratio increased after BoNT-A. Correlations revealed that higher GABA was associated with lower VAS and attack frequency post-treatment. Conclusions: BoNT-A provided short-term clinical improvement with distinct neurochemical changes, including increased plasma SP and 5-HT, decreased urinary 5-HT, reduced glutamine, and a higher Glu/Gln ratio. These biomarkers, particularly Glu/Gln, may serve as indicators of cortical excitability and therapeutic response in CM.

Objective: Preanalytical errors account for the vast majority of preanalytical incidents and remain a fundamental threat to the reliability of test results. Although the types and frequencies of these errors have been extensively studied in the literature, their time-dependent variability has received comparatively little attention. This study aimed to evaluate how preanalytical specimen rejection rates vary across intraday time intervals and to assess the independent influence of time on preanalytical quality. Methods: This retrospective observational study included a total of 579,845 specimens accepted by the central laboratory of Istanbul Atlas University Hospital between January 2024 and December 2025. Specimens were analyzed with respect to preanalytical rejection reasons, the distribution and rate of these reasons across clinical units, and time of day. Each day was divided into six equal four-hour intervals: Z1 (00:00–04:00), Z2 (04:00–08:00), Z3 (08:00–12:00), Z4 (12:00–16:00), Z5 (16:00–20:00), and Z6 (20:00–24:00). Statistical analyses were performed using the Pearson chi-square test, and effect sizes were quantified using Cramér’s V coefficient. Results: Of the 579,845 specimens examined, 4365 were rejected, yielding an overall rejection rate of 0.79%. Rejection rates were found to be non-uniformly distributed across the day (p < 0.001). The highest rejection rate was observed during the Z2 interval (04:00–08:00) at 1.98%, whereas the lowest was recorded during Z3 (08:00–12:00) at 0.45%. Negative binomial regression analysis identified the Z2 interval as the only time period independently associated with an increased rejection risk Incidence Rate Ratio (IRR) = 1.63; 95% Confidence Interval (CI): 1.22–2.19. Among clinical units, the highest rejection rate was recorded in the emergency department (1.92%). Analysis of error types revealed that the majority of rejections were attributable to hemolysis (47.5%) and clotted specimens (26.3%). Hemolysis rates peaked in the emergency department, while clotted specimens occurred more frequently within intensive care units. Analysis of time and error interactions revealed that clotted specimens peaked during Z1 and Z2, whereas hemolysis became the primary cause of rejection during Z3 and Z4. Conclusions: Preanalytical specimen rejection rates exhibited significant variation according to time of day, clinical unit, and error type, with time emerging as a factor independently associated with preanalytical quality. The coexistence of elevated rejection risk during Z2 (04:00–08:00) and markedly low rejection rates during Z3 (08:00–12:00) indicates that the relationship between workload and error frequency is not linear. Although hemolysis and clotted specimens constituted the dominant error types, their distribution followed distinct patterns depending on the clinical unit and time interval. These results underscore the necessity of time-based monitoring to pinpoint unit-specific risks, providing a clear roadmap for targeted quality improvement interventions.

Background/Objectives: Awake procedures performed under spinal anesthesia (SA) have been associated with reduced hospitalization, costs, and postoperative complications compared with general anesthesia (GA). Endocan, an endothelial cell-specific proteoglycan, serves as a biomarker of endothelial activation and vascular dysfunction and may reflect the differential vascular and immunomodulatory effects of anesthetic techniques. This prospective observational study aimed to compare perioperative changes in circulating endocan levels between patients undergoing surgery under GA and SA. Methods: Eighty adult patients (aged 18–65 years, ASA I–II) scheduled for elective surgery were included and assigned to GA (n = 42) or SA (n = 38) based on standard clinical indications. Serum endocan levels were measured preoperatively, at 6 h, and at 24 h postoperatively using an ELISA assay. Results: In the GA group, endocan levels increased significantly from baseline (304.5 ± 80.7 pg/mL) to 6 h (511.5 ± 88.7 pg/mL, p < 0.001), and although partially decreased by 24 h (427.5 ± 87.9 pg/mL, p < 0.001), remained above baseline. In the SA group, endocan rose from baseline (320.7 ± 72.5 pg/mL) to 6 h (415.2 ± 79.5 pg/mL, p < 0.001) but returned near baseline at 24 h (352.6 ± 84.7 pg/mL, p = 0.233). Conclusions: These findings suggest that while surgery induces endothelial activation in both groups, GA is associated with a more sustained endothelial response than SA.