Astra Vitkauskienė

Gender-specific cold responses induce a similar body-cooling rate but different neuroendocrine and immune responses ☆

This study investigated whether there are any gender differences in body-heating strategies during cold stress and whether the immune and neuroendocrine responses to physiological stress differ between men and women. Thirty-two participants (18 men and 14 women) were exposed to acute cold stress by immersion to the manubrium level in 14 °C water. The cold stress continued until rectal temperature (TRE) reached 35.5 °C or for a maximum of 170 min. The responses to cold stress of various indicators of body temperature, insulation, metabolism, shivering, stress, and endocrine and immune function were compared between men and women. During cold stress, TRE and muscle and mean skin temperatures decreased in all subjects (P<0.001). These variables and the TRE cooling rate did not differ between men and women. The insulative response was greater in women (P<0.05), whereas metabolic heat production and shivering were greater (P<0.05) in men. Indicators of cold strain did not differ between men and women, but men exhibited larger changes in the indicators of neuroendocrine (epinephrine level) and in immune (tumor necrosis factor-α level) responses (both P<0.05). The results of the present study indicated that men exhibited a greater metabolic response and shivering thermogenesis during acute cold stress, whereas women exhibited a greater insulative response. Despite the similar experience of cold strain in men and women, the neuroendocrine and immune responses were larger in men. Contrary to our expectations, the cooling rate was similar in men and women.

Plant-expressed pyocins for control of Pseudomonas aeruginosa

The emergence, persistence and spread of antibiotic-resistant human pathogenic bacteria heralds a growing global health crisis. Drug-resistant strains of gram-negative bacteria, such as Pseudomonas aeruginosa, are especially dangerous and the medical and economic burden they impose underscore the critical need for finding new antimicrobials. Recent studies have demonstrated that plant-expressed bacteriocins of the colicins family can be efficient antibacterials against all major enteropathogenic strains of E. coli. We extended our studies of colicin-like bacteriocins to pyocins, which are produced by strains of P. aeruginosa for ecological advantage against other strains of the same species. Using a plant-based transient expression system, we expressed six different pyocins, namely S5, PaeM, L1, L2, L3 and one new pyocin, PaeM4, and purified them to homogeneity. Among these pyocins, PaeM4 demonstrated the broadest spectrum of activity by controlling 53 of 100 tested clinical isolates of P. aeruginosa. The activity of plant-made pyocins was confirmed in the agar drop, liquid culture susceptibility and biofilm assays, and in the Galleria mellonella animal infection model.

Prevalence of O25b-ST131 clone among Escherichia coli strains producing CTX-M-15, CTX-M-14 and CTX-M-92 β-lactamases

Abstract Background: Dissemination of multidrug-resistant Escherichia coli is closely associated with the worldwide spread of a single clone ST131, which is the main cause of urinary tract and bloodstream infections in patients from nursing homes and immunocompromised patients. The aim of our study was to determine the prevalence of ST131 clone and the replicons involved in the spread of blaCTX-M genes among O25b-ST131 CTX-M-producing E. coli isolates in Lithuania. Methods: The strains included in this study were screened for CTX-M β-lactamase-encoding genes, phylogenetic groups and ST131 clone by PCR. Bacterial conjugation was performed to identify plasmid replicon types responsible for blaCTX-M genes dissemination. Results: A total of 158 E. coli clinical non-duplicate ESBL isolates were analyzed. Nearly half (n = 67, 42.4%) of the investigated E. coli isolates belonged to phylogenetic group B2. The isolates producing CTX-M-92 β-lactamases were identified to be the ST131 clone more frequently than the non-ST131 clone (11.5% vs. 3.1%, p = .035). The CTX-M-15 isolates were identified as ST131 isolates less frequently than non-ST131 isolates (50.8% vs. 71.1%; p = .015). The ST131 clone isolates contained type L/M and A/C replicons; a fused FII/FIB replicon was found in four isolates (23.5%). Type HI1 replicon was identified in ST131 E. coli isolates producing CTX-M-15 β-lactamases. Conclusions: This study demonstrates the predominance of the ST131 clone among CTX-M β-lactamase-producing E. coli isolates. Dissemination of blaCTX-M genes in ST131 strains can be linked not only to highly adapted IncF plasmids such as FII/FIB and FII, but also to plasmid replicon types A/C, L/M and HI1.

Associations of HLA DRB1 alleles with IgG oligoclonal bands and their influence on multiple sclerosis course and disability status

BACKGROUND AND AIM Oligoclonal bands (OCB) may be associated with the genes of HLA complex, which allows to consider the possible interaction of genetic and immunological factors and its importance in the development and progression of multiple sclerosis (MS). The aim of this study was to evaluate the associations between HLA DRB1 alleles and oligoclonal bands (OCBs) in the disease course and disability of multiple sclerosis (MS) patients. MATERIALS AND METHODS This was a prospective study of 120 patients with MS. HLA DRB1 alleles were genotyped using the polymerase chain reaction. Matched cerebrospinal fluid (CSF) and plasma samples were analyzed using isoelectric focusing and IgG specific immunofixation to test for the presence of intrathecal specific OCB. RESULTS HLA DRB1*08 allele was related to a lower degree of disability. Oligoclonal bands were an independent and significant factor that influenced disability status irrespective of HLA DRB1* 04, *07, *08, *13, *15 and *16 alleles. Age at the onset and duration of the disease were independent and significant factors for MS progression in all logistic regression models with each newly added HLA DRB1 allele. HLA DRB1*08 allele was related to 75% lower odds that relapsing remitting (RR) MS will change to a progressive course MS irrespective of the other factors investigated. Detection of OCBs in the CSF was associated with the higher possibility of RR MS progression in all cases, except when the *08 allele was present. CONCLUSIONS OCBs had an influence on disability status, while HLA DRB1*08 allele was significantly associated with lower possibility that RR MS will change to progressive course MS.

The effect of dichloroacetate on male rat thymus and on thymocyte cell cycle

The study aim was to investigate the effect of dichloroacetate (DCA) on thymus and the thymocyte cycle in rats. Wistar male gonad-intact and castrated rats (4–5 weeks) were investigated in the following groups: (1) control; (2) treated with DCA; and (3) treated with the DCA and sodium valproate (NaVP) combination. Rats were treated for 4 weeks with DCA 200 mg/kg/day alone and 300 mg/kg/day of NaVP plus 200 mg/kg/day of DCA (every second week, beginning with NaVP). After the experiment, the thymus was weighted, and the thymus lobe was taken for thymocyte flow cytometry. In gonad-intact rats, the thymus weight of the control was higher than in rats treated with DCA (P <0.001) or with the NaVP–DCA combination (P <0.04); a comparison of thymus weight between DCA- and NaVP–DCA-treated groups revealed a higher thymus weight loss in the DCA-treated group (P <0.03). Flow cytometry shows that DCA treatment increased the percentage of cells in the G2–M phase (P <0.03) and reduced in G1–G0 (P <0.02). The DCA treatment effect was determined only in gonad-intact but not in castrated rats. The authors discuss the possible DCA and NaVP interaction mechanisms.

Use of interferon-gamma release assay and tuberculin skin test in diagnosing tuberculosis in Lithuanian adults: A comparative analysis

BACKGROUND AND OBJECTIVE Lithuania belongs to the group of countries with a high-incidence of tuberculosis (TB). Some scientific studies show that the interferon-gamma release assay is more accurate and correlates more highly with TB exposure as compared to the tuberculin skin test (TST). This study aimed at comparing the efficacy between the T SPOT TB and TST for diagnosing TB among Lithuanian adults. MATERIALS AND METHODS Individuals with diagnosed TB, healthcare workers with known risk for TB and individuals without any known risk for TB underwent clinical examinations, interviews about their history of TB exposure and chest radiography. Then the TST and the T SPOT TB were performed on patients. RESULTS A positive T SPOT TB was more common in the group with diagnosed TB compared to healthcare workers and the low risk for TB groups (97.5%, 36.4%, and 0%, respectively, P<0.01). Positive TST results did not differ between the groups with diagnosed TB and the healthcare workers (92.5% vs. 95.5%, P>0.05). Agreement between TST and T SPOT TB was poor (kappa 0.14, P>0.05). T SPOT TB had higher specificity and sensitivity compared to TST (area under the ROC 0.9±0.04, P<0.01, vs. 0.5±0.06, P>0.05). CONCLUSIONS The T SPOT TB showed greater accuracy in diagnosing TB than TST did. Positive T SPOT TB result but not the TST was more common in patients with diagnosed TB.

Multidrug-resistant tuberculosis in Lithuania – Still a long way ahead

Despite the recent advances in the diagnosis of tuberculosis, treatment of the disease, for the most part, remains the same as it was half a century ago. In recent years only two new anti-tuberculosis drugs have been approved by the European Medicines Agency and Food and Drug Administration. Though the prevalence of this disease is slowly decreasing all over Europe, new challenges appear. One of them is multidrug-resistant tuberculosis (MDR-TB). This problem is especially prominent in Lithuania, which is one of the 27 high MDR-TB burden countries in the world and falls behind neighboring countries in terms of the prevalence of the disease. The objective of this paper was to review the situation of tuberculosis and MDR-TB in Lithuania, and current available methods of treatment, control and diagnosis of this disease.

Impact of etiology on course and outcomes of severe acute pancreatitis

BACKGROUND AND OBJECTIVE Since the influence of etiological factors on the course and outcomes of acute pancreatitis (AP) is not fully understood yet, the aim of the study was to compare the outcomes of alcoholic and biliary severe acute pancreatitis (SAP). MATERIALS AND METHODS We investigated 81 patients with alcoholic and biliary SAP. Demographic data, etiologic factors, severity scores, intra-abdominal pressure, imaging studies, interventions, and treatment outcomes were prospectively entered into specially maintained database and subsequently analyzed. RESULTS No statistically significant difference was observed in the prevalence of SAP in biliary and alcoholic AP groups (P=0.429). Although, in the biliary SAP group patients were predominantly elderly women (P=0.003), the total in-hospital stay was longer in alcoholic SAP patients (P=0.021). The abdominal compartment syndrome developed more frequently (P=0.041) and necrosectomy was more frequently performed in alcoholic SAP group (not statistically significant). Although not statistically significant, a lower mortality rate among biliary SAP patients (25.0% vs. 13.5%) was observed. CONCLUSIONS We defined a trend toward decreased incidence of infected necrosis in larger volume (≥30%) pancreatic necrosis, absence of abdominal compartment syndrome, lower rate of necrosectomies, shorter in-hospital stay, and an insignificantly reduced mortality rate in biliary SAP patients, indicating more favorable course of biliary SAP.

New Sepsis Biomarker – Presepsin. Its Benefits and Future

Ankstyva sepsio diagnozė yra kritiskai svarbi sėkmingam sepsio gydymui. Ne mažiau svarbu nustatyti sepsio prognoze bei sekti gydymo efektyvumą. Pastaraisiais metais pastebėtas sepsio atvejų augimas, todėl svarbu surasti patikimą ir greitai nustatomą žymenį sepsio diagnostikai ir prognozei vertinti. Sioje apžvalgoje siekta aptarti naująjį sepsio žymenį – presepsiną ir palyginti jį su kitais populiariaisiais diagnostiniais sepsio rodikliais (prokalcitoninu, C-reaktyviu baltymu ir interleukinu 6) pagal specifiskumą, jautrumą ir prognozine verte. Isvados – tyrimų apžvalga parodė, kad didžiausią diagnostine ir prognozine verte pacientų isgyvenamumui turi presepsinas, lyginant su kitais žymenimis, siuo metu naudojamais sepsio diagnostikoje. Norint įsitikinti akivaizdžiu presepsino pranasumu, reikėtų atlikti daugiau klinikinių tyrimų, taciau jau dabar galime teigti, kad sis žymuo klinikinėje praktikoje yra pakankamai patikimas prognozinis sepsio rodiklis. doi:10.5200/sm-hs.2012.072