Erfahrungsbericht über die Haltung und deutsche Erstzucht der Borneo-Flussschildkröte (Orlitia borneensis Gray, 1873) im Zoo Dresden

Dresden Zoo bred successfully the Malaysian giant turtle (Orlitia borneensis) in summer 2012. This was the first successful breeding of this species in Germany.Little is known about biology and behaviour of this large river turtle and keeping and especially breeding of this endangered species in captivity is a rarity. In order to create optimal breeding conditions Dresden Zoo rebuilt an enclosure for the turtles in 2010. An area with soil and sand was built for the expected egg deposition. After arranged matings one female dug a nest on this area and buried her eggs. Nine eggs were secured and transferred into an incubator in a box filled with a 1:1 mixture of vermiculite and water. The average temperature was 29 °C. After problems with the temperature regulation the damaged incubator had to be replaced. Because of an estimated incubation period of 3–4 months, one egg was opened on day 127 of incubation. A live hatchling with a big yolk sac was fetched. Because of the non-reabsorbed yolk sac the hatchling was further incubated. On day 154 of incubation all eggs were manually opened and the hatchlings were fetched. All of these hatchlings showed a non-reabsorbed yolk sac and were incubated onwards in a box with wet paper towel until the yolk sac was completely reabsorbed. After that the hatchlings were housed solitarily in a box with water of approximately 4 cm height and a small land area. Two days after housing food was offered for the first time. All hatchlings accepted the offered food consisting of herbal as well as of animal products and later turtle pellets and self-made turtle jelly.Though little is known about breeding this species, the breeding success of Dresden Zoo demonstrates a possible approach to this topic. But there are still things to optimize. For example the manual hatching is something that should be avoided in future. Fertilization and hatching rate of 100% are promising and up to date eight out of nine hatchlings are still alive.     

Genome annotation and antimicrobial properties of Bacillus toyonensis VU‐DES13, isolated from the Folsomia candida gut

Antibiotic resistance necessitates the search for new bioactive compounds with novel mechanisms of action. Natural products derived from bacteria and fungi are widely used in the field of medicine and new environments can be explored as sources of antimicrobials. Bacteria associated with springtails have shown high inhibitory activity against pathogens. Here, we characterized a bacterial strain with high potential for antimicrobial activity, isolated from the gut of the springtail Folsomia candida Willem (Collembola: Isotomidae). The strain was characterized using the ‘analytical profile index’ and the ‘minimal inhibitory concentration’ assay to test for antibiotic resistance. Agar overlay and agar disk diffusion assays were used to test the inhibitory activity of the strain and its extract against a variety of pathogens, and reporter assays were used to investigate the mode of action. High‐performance liquid chromatography was used to analyze and fractionate the extract of bacterial culture, followed by additional assays on the fractions. The genome of the strain was screened for presence of antibiotic resistance genes and secondary metabolite gene clusters. The isolate was identified as Bacillus toyonensis Jiménez et al., but it displayed differences in metabolic profile when compared to the type species. The isolate was highly resistant to penicillin and inhibited the growth of a variety of pathogenic microorganisms. Genome analysis revealed an enrichment of resistance genes for β‐lactam antibiotics compared to the type isolate. Also, secondary metabolite clusters involved in the production of siderophores, bacteriocins, and nonribosomal peptide synthetases were identified. In conclusion, a unique Bacillus strain was isolated from the gut of F. candida, for which we provide evidence of inhibitory activity against an array of pathogens. This, coupled with high resistance to penicillin as substantiated by the presence of resistance genes, points to the potential of B. toyonensis VU‐DES13 to provide a new source of antimicrobial compounds.     

In vitro modulation of steroid 5alpha-reductase activity by phospholipases in epithelium and stroma of human benign prostatic hyperplasia

Membrane components, such as phospholipids, play an important role in the regulation of prostatic 5alpha-reductase activity. To describe in more detail the impact of such regulation on 5alpha-reductase activity, epithelial and stromal cell homogenates of human BPH were treated with phospholipases to specifically alter the structure of cellular phospholipid components. Phospholipase A(2) (PLA(2)) was used to alter the structure of the nonpolar, hydrophobic region of the membrane bilayer. Various types of phospholipase C (PLC) affect the polar, hydrophilic region of phospholipids. In epithelium and stroma, 5alpha-reductase activity was dose-dependently inhibited by PLA(2) and PLC type III. In epithelium and stroma, the mean IC(50) values of PLA(2) were 9.4 +/- 1.1 and 13.9 +/- 2.6 [U/mg protein +/- SEM], respectively. The mean IC(50) values of PLC type III in epithelium and stroma were 4.5 +/- 1.2 and 1.7 +/- 0.2 [U/mg protein +/- SEM], respectively. In epithelium as well as in stroma, 5alpha-reductase activity was more greatly inhibited by PLC type III than by PLA(2). Both in epithelium and stroma, PLA(2) significantly decreased the V(max) of 5alpha-reductase whereas its K(m) remained unaffected. A similar decrease in V(max) was found with PLC type III in epithelium and stroma. Furthermore, the K(m) of epithelial 5alpha-reductase increased significantly following the addition of PLC type III. The two phospholipases, with their specific substrate affinities and sites of hydrolysis, exhibited significantly different effects on 5alpha-reductase, indicating that 5alpha-reductase activity is not unspecifically affected by modification of the hydrophilic milieu. Rather, 5alpha-reductase activity is specifically modulated by various phospholipids and/or phospholipolysis mediated degradation products. These findings suggest that the structural composition of the lipid environment plays a fundamental role in the post-translational regulation of 5alpha-reductase activity in the epithelium and stroma of human BPH. Thus, changes in membrane phospholipid content seem to be instrumental in the expression of DHT-dependent processes.     

Ethnic‐specific Correlations of Visfatin With Circulating Markers of Endothelial Inflammation and Function

Sub‐Saharan Africa is afflicted by high hypertension prevalence that is expected to rise even further along with increasing obesity rates. The present study aimed to investigate the role of visfatin in obesity and to explore associations of visfatin with markers of endothelial function and hemodynamics in African women compared to a well‐matched white sample. The present study involved urban African (n = 102) and white (n = 115) women from South Africa, individually matched for age and BMI. We measured blood pressure, cardiac output, and arterial compliance noninvasively, and analyzed visfatin as well as circulating markers of vascular function and inflammation in serum. Serum visfatin concentration did not differ between African and white women. Visfatin was unrelated to obesity in African women but positive associations for total and abdominal obesity were found in white women. Age‐ and obesity‐adjusted univariate and multivariate analyses revealed significant positive associations of visfatin with endothelin‐1 and fibrinogen in African women. Identical analyses in white women indicated a positive association of visfatin with C‐reactive protein and von Willebrand factor. Our findings suggest a possible role of visfatin in the cardiovascular system that seems to be independent of obesity in the African women.     

Cortisol Awakening Response Is Linked to Disease Course and Progression in Multiple Sclerosis

Objectives

Dysregulation of the hypothalamus-pituitary-adrenal (HPA) axis has frequently been reported in multiple sclerosis (MS). So far, HPA axis function in MS has predominantly been studied under pharmacological stimulation which is associated with a series of methodological caveats. Knowledge of circadian cortisol patterns and cortisol awakening response (CAR) is still limited.

Methods

A total of 77 MS patients (55 relapsing-remitting MS (RRMS)/22 secondary-progressive MS (SPMS)) as well as 34 healthy control (HC) subjects were enrolled. Diurnal cortisol release was assessed by repeated salivary cortisol sampling. Neurological disability was rated by the Kurtzke’s Expanded Disability Status Scale (EDSS). Depressive symptoms and perceived stress were assessed by self-report measures.

Results

RRMS but not SPMS patients differed in circadian cortisol release from HC subjects. Differences in cortisol release were restricted to CAR. Treated and treatment naïve RRMS patients did not differ in CAR. In a RRMS follow-up cohort (nine months follow-up), RRMS patients with EDSS progression (≥0.5) expressed a significantly greater CAR compared to HC subjects. RRMS patients with a stable EDSS did not differ from HC subjects. Neither depressive symptoms nor perceived stress ratings were associated with CAR in RRMS patients. In a step-wise regression analysis, EDSS at baseline and CAR were predictive of EDSS at follow-up (R² = 67%) for RRMS patients.

Conclusions

Circadian cortisol release, in particular CAR, shows a course specific pattern with most pronounced release in RRMS. There is also some evidence for greater CAR in RRMS patients with EDSS progression. As a consequence, CAR might be of predictive value in terms of neurological disability in RRMS patients. The possible role of neuroendocrine-immune interactions in MS pathogenesis is further discussed.     

Functional energetics of CD4+-cellular immunity in monoclonal antibody-associated progressive multifocal leukoencephalopathy in autoimmune disorders

Background

Progressive multifocal leukoencephalopathy (PML) is an opportunistic central nervous system- (CNS-) infection that typically occurs in a subset of immunocompromised individuals. An increasing incidence of PML has recently been reported in patients receiving monoclonal antibody (mAb) therapy for the treatment of autoimmune diseases, particularly those treated with natalizumab, efalizumab and rituximab. Intracellular CD4⁺-ATP-concentration (iATP) functionally reflects cellular immunocompetence and inversely correlates with risk of infections during immunosuppressive therapy. We investigated whether iATP may assist in individualized risk stratification for opportunistic infections during mAb-treatment.

Methodology/Principal Findings

iATP in PHA-stimulated, immunoselected CD4⁺-cells was analyzed using an FDA-approved assay. iATP of mAb-associated PML (natalizumab (n = 8), rituximab (n = 2), efalizumab (n = 1)), or other cases of opportunistic CNS-infections (HIV-associated PML (n = 2), spontaneous PML, PML in a psoriasis patient under fumaric acids, natalizumab-associated herpes simplex encephalitis (n = 1 each)) was reduced by 59% (194.5±29 ng/ml, mean±SEM) in comparison to healthy controls (HC, 479.9±19.8 ng/ml, p<0.0001). iATP in 14 of these 16 patients was at or below 3^rd percentile of healthy controls, similar to HIV-patients (n = 18). In contrast, CD4⁺-cell numbers were reduced in only 7 of 15 patients, for whom cell counts were available. iATP correlated with mitochondrial transmembrane potential (ΔΨ_m) (iATP/ΔΨ_m−correlation:tau = 0.49, p = 0.03). Whereas mean iATP of cross-sectionally analysed natalizumab-treated patients was unaltered (448.7±12 ng/ml, n = 150), iATP was moderately decreased (316.2±26.1 ng/ml, p = 0.04) in patients (n = 7) who had been treated already during the pivotal phase III trials and had received natalizumab for more than 6 years. 2/92 (2%) patients with less than 24 months natalizumab treatment revealed very low iATP at or below the 3^rd percentile of HC, whereas 10/58 (17%) of the patients treated for more than 24 months had such low iATP-concentrations.

Conclusion

Our results suggest that bioenergetic parameters such as iATP may assist in risk stratification under mAb-immunotherapy of autoimmune disorders.     

Determination of baroreflex sensitivity during the modified Oxford maneuver by trigonometric regressive spectral analysis

Background

Differences in spontaneous and drug-induced baroreflex sensitivity (BRS) have been attributed to its different operating ranges. The current study attempted to compare BRS estimates during cardiovascular steady-state and pharmacologically stimulation using an innovative algorithm for dynamic determination of baroreflex gain.

Methodology/Principal Findings

Forty-five volunteers underwent the modified Oxford maneuver in supine and 60° tilted position with blood pressure and heart rate being continuously recorded. Drug-induced BRS-estimates were calculated from data obtained by bolus injections of nitroprusside and phenylephrine. Spontaneous indices were derived from data obtained during rest (stationary) and under pharmacological stimulation (non-stationary) using the algorithm of trigonometric regressive spectral analysis (TRS). Spontaneous and drug-induced BRS values were significantly correlated and display directionally similar changes under different situations. Using the Bland-Altman method, systematic differences between spontaneous and drug-induced estimates were found and revealed that the discrepancy can be as large as the gain itself. Fixed bias was not evident with ordinary least products regression. The correlation and agreement between the estimates increased significantly when BRS was calculated by TRS in non-stationary mode during the drug injection period. TRS-BRS significantly increased during phenylephrine and decreased under nitroprusside.

Conclusions/Significance

The TRS analysis provides a reliable, non-invasive assessment of human BRS not only under static steady state conditions, but also during pharmacological perturbation of the cardiovascular system.