The actinobacterial signature protein ParJ (SCO1662) regulates ParA polymerization and affects chromosome segregation and cell division during Streptomyces sporulation

Bacterial chromosome segregation usually involves cytoskeletal ParA proteins, ATPases which can form dynamic filaments. In aerial hyphae of the mycelial bacterium Streptomyces coelicolor, ParA filaments extend over tens of microns and are responsible for segregation of dozens of chromosomes. We have identified a novel interaction partner of S. coelicolor ParA, ParJ. ParJ negatively regulates ParA polymerization in vitro and is important for efficient chromosome segregation in sporulating aerial hyphae. ParJ-EGFP formed foci along aerial hyphae even in the absence of ParA. ParJ, which is encoded by sco1662, turned out to be one of the five actinobacterial signature proteins, and another of the five is a ParJ paralogue. We hypothesize that polar growth, which is characteristic not only of streptomycetes, but even of simple Actinobacteria, may be interlinked with ParA polymer assembly and its specific regulation by ParJ.     

The circulatory influence on development of age-related macular degeneration and hearing and equilibrium impairments

This study attempts to answer the question if any level of head and neck circulation takes a part in development of Age-Related Macular Degeneration (ARMD) and hearing and equilibrium impairments. Condition of large blood vessels was examined by Color-Doppler ultrasound, and carotid and ophthalmic arteries were included. The microcirculatory changes were examined directly by fundus photography and fluorescein angiography and indirectly testing hearing and equilibrium. The study group included 40 patients (21 females, 19 males) aging from 53 to 84 years with different stages of ARMD. The control group included 40 patients (18 females, 22 males) aging from 51 to 82 years without ARMD. Patients were inhabitants of Primorsko-Goranska County. There was no relationship between ARMD and condition of large blood vessels because significant stenosis of carotid arteries was found in 2 patients (5%) in study group and 3 patients (7.5%) in the control group (p > 0.05). On the contrary, we found correlation between ARMD and hearing (p = 0.0127) and equilibrium impairments (p = 0.0242). Fluorescein angiograms shows raised number of ischemic retinal capillaries in patients with ARMD (p = 0.0053). Results lead to conclusion that circulatory disorders on microcirculatory level take a great part in development of ARMD and hearing and equilibrium impairments in the elderly. The key is damage of sensory cells of the retina and inner ear caused by microcirculatory disorders. Interesting data was noticed that 9 patients with more serious ARMD on one side of head had greater hearing loss on the same side. If we find a new treatment for microcirculatory disorders, maybe we can treat both sensory impairments in earlier stage.     

Expression of matrix metalloproteinase-1 in uterosacral ligaments tissue of women with genital prolapse

Collagen metabolism is altered in the pelvic organ tissues of women with genital prolapse. The aim of this study was to compare collagen metabolism by measuring matrix metalloproteinase-1 (MMP-1) expression in uterosacral ligament tissues of postmenopausal women with and without genital prolapse. Uterosacral ligament tissues were obtained at the time of abdominal or vaginal surgery from twenty-four patients with pelvic organ prolapse (POP) and 21 women who underwent gynecologic surgery for benign indications. The tissue samples were analyzed by immunohistochemistry. There were no differences in age, BMI and parity between two groups. The patients with genital prolapse demonstrated significantly higher occurences of MMP-1 expression compared to controls. These findings indicate that increased MMP-1 expression in uterosacral ligaments is associated with genital prolapse. Our data are consistent with the theory that increased collagen breakdown may play an important role in the onset and development of pelvic organ prolapse (POP).     

Vindija cave and the modern human peopling of Europe

Vindija cave in Croatia has yielded the youngest securely dated Neandertal skeletal remains in Central/Eastern Europe. In addition, these remains have been found in association with archaeological material exhibiting Upper Paleolithic elements. Due to its geographic location and date, the Vindija remains are particularly crucial for the understanding of initial modern human peopling of Europe and the nature of the Neandertal demise. The significance of archaeological and paleontological finds and hominin fossils from this site is discussed in the light of new finds at Vindija and recent developments in the fields of paleoanthropology and prehistoric archaeology. Furthermore, the impact of revised chronology for several crucial specimens and sites throughout Europe, including Vindija, is discussed.     

Dissecting the molecular architecture and origin of Bayash Romani patrilineages: genetic influences from South-Asia and the Balkans

The Bayash are a branch of Romanian speaking Roma living dispersedly in Central, Eastern, and Southeastern Europe. To better understand the molecular architecture and origin of the Croatian Bayash paternal gene pool, 151 Bayash Y chromosomes were analyzed for 16 SNPs and 17 STRs and compared with European Romani and non-Romani majority populations from Europe, Turkey, and South Asia. Two main layers of Bayash paternal gene pool were identified: ancestral (Indian) and recent (European). The reduced diversity and expansion signals of H1a patrilineages imply descent from closely related paternal ancestors who could have settled in the Indian subcontinent, possibly as early as between the eighth and tenth centuries AD. The recent layer of the Bayash paternal pool is dominated by a specific subset of E1b1b1a lineages that are not found in the Balkan majority populations. At least two private mutational events occurred in the Bayash during their migrations from the southern Balkans toward Romania. Additional admixture, evident in the low frequencies of typical European haplogroups, J2, R1a, I1, R1b1b2, G, and I2a, took place primarily during the early Bayash settlement in the Balkans and the Romani bondage in Romania. Our results indicate two phenomena in the Bayash and analyzed Roma: a significant preservation of ancestral H1a haplotypes as a result of considerable, but variable level of endogamy and isolation and differential distribution of less frequent, but typical European lineages due to different patterns of the early demographic history in Europe marked by differential admixture and genetic drift.     

Zur Morphologie und Systematik desTrebouxia-Phycobionten im Thallus vonUsnea longissima (Lecanorales)

In the lichen genusUsnea different species ofTrebouxia-phycobionts as well as different haustorial types are known. The isolated and cultivated phycobiont ofUsnea longissima Ach. was studied by light- and electron microscopy and resembles in cytomorphological details the type ofTrebouxia impressa Ahmad. In addition to simple wall-to-wall contacts between the symbiotic components also intraparietal (=intrawall-)haustoria could be observed as the normal interaction type.

Frau Prof. Dr.Elisabeth Tschermak-Woess zu ihrem 70. Geburtstag gewidmet.     

The application of an averaging method to intermittently modified and endogenously generated spike activities of neurons in mollusc ganglia

The averaging method was applied for the analysis of the effect of intermittent light as well as for the analysis of the spontaneous spike activities of burster neurons in Helix pomatia and Aplysia depilans ganglia. Owing to such analyses by means of which the unwanted effects of permanently present noise (i.e., irregular frequency modulation of neuron impulse activity) were diminished, the dynamics of the neurons reaction to light and the longer time effects of intermittent illumination on neurons spontancous activity could be observed. The functional characteristics of burster neurons were determined by averaging and the least squares and equalization methods. The results were presented in the table and in two average curves which are asymmetrical with a horizontal asymptote. From these data it was concluded that the dynamics of the spontaneous activity of the two burster neurons in both specia is similar. The possibilities and limitations of the method in physiological analyses are discussed.     

Cell apoptosis as assessed by M30 expression in keratoacanthoma and squamous cell carcinoma

Involution displayed by keratoacanthoma (KA) represents an important difference between KA and squamous cell carcinoma (SCC). It has been suggested that apoptosis plays a part in process of involution of KA. Altogether 150 specimens were included in this study, 30 cases of each; normal skin (NS), proliferative (pKA) and regressing keratoacanthoma (rKA), well differentiated (wdSCC) and poorly differentiated (pdSCC) squamous cell carcinoma. All samples were examined immunohistochemically for expression of M30 protein. A significantly lower number of M30 positive cells has been detected in NS as compared to skin tumors examined (p<0.001), except for rKA (p=0.057). The highest percentage of M30 positive cells was detected in pdSCC (p<0.001) as compared with all other examined groups. Keratinocytes of normal and changed epidermis expressing higher levels of M30 protein were predominately found in sun-exposed areas (chi2=14.93; p=0.060). There was an increasing trend of M30 protein expression with increasing age of the patient in NS and skin tumors examined. Majority of skin tumors with higher percentage of M30 positive cells tended to display higher Ki-67 expression. M30 expression was highly correlated with bak (r=0.811; p=0.048) and granzyme B expression in rKA (r=0.733; p=0.015). Cell apoptosis as assessed by M30 expression is, generally, increased in examined skin tumors and related to cell proliferation. Cell apoptosis mediated by bak and granzyme B expression could contribute to KA regression.     

Inhibition of AChE by malathion and some structurally similar compounds

Inhibition of bovine erythrocyte acetylcholinesterase (free and immobilized on controlled pore glass) by separate and simultaneous exposure to malathion and malathion transformation products which are generally formed during storage or through natural or photochemical degradation was investigated. Increasing concentrations of malathion, its oxidation product malaoxon, and its isomerisation product isomalathion inhibited free and immobilized AChE in a concentration-dependent manner. KI, the dissociation constant for the initial reversible enzyme inhibitor-complex, and k3, the first order rate constant for the conversion of the reversible complex into the irreversibly inhibited enzyme, were determined from the progressive development of inhibition produced by reaction of native AChE with malathion, malaoxon and isomalathion. KI values of 1.3 x 10(-4) M(-1), 5.6 x 10(-6) M(-1) and 7.2 x 10(-6)M(-1) were obtained for malathion, malaoxon and isomalathion, respectively. The IC50 values for free/immobilized AChE, (3.7 +/- 0.2) x 10(-4) M/(1.6 +/-0.1) x 10(-4), (2.4 +/- 0.3) x 10(-6)/(3.4 +/- 0.1) x 10(-6)M and (3.2 +/- 0.3) x 10(-6) M/(2.7 +/- 0.2) x 10(-6) M, were obtained from the inhibition curves induced by malathion, malaoxon and isomalathion, respectively. However, the products formed due to photoinduced degradation, phosphorodithioic O,O,S-trimethyl ester and O,O-dimethyl thiophosphate, did not noticeably affect enzymatic activity, while diethyl maleate inhibited AChE activity at concentrations > 10mM. Inhibition of acetylcholinesterase increased with the time of exposure to malathion and its inhibiting by-products within the interval from 0 to 5 minutes. Through simultaneous exposure of the enzyme to malaoxon and isomalathion, an additive effect was achieved for lower concentrations of the inhibitors (in the presence of malaoxon/isomalathion at concentrations 2 x 10(-7) M/2 x 10(-7) M, 2 x 10(-7) M/3 x 10(-7)M and 2 x 10(-7) M/4.5 x 109-7) M), while an antagonistic effect was obtained for all higher concentrations of inhibitors. The presence of a non-inhibitory degradation product (phosphorodithioic O,O,S-trimethyl ester) did not affect the inhibition efficiencies of the malathion by-products, malaoxon and isomalathion.     

Off-pump coronary bypass surgery adversely affects alveolar gas exchange

While the introduction of off-pump myocardial revascularization (OPCAB) has initially shown promise in reducing respiratory complications inherent to conventional coronary surgery, it has failed to eradicate them. Our study focused on quantifying the lactate release from the lungs and the dysfunction at the level of the alveolar-capillary membrane precipitated by OPCAB at different time points after the insult. Furthermore, we aimed to determine the impact of pulmonary lactate production on systemic lactic acid concentrations. The study was conducted in a prospective observational fashion. Forty consecutive patients undergoing OPCAB were analyzed. The mean patient age was 60 +/- 10 years. The mean EUROScore was 3.8 +/- 2.9. The alveolar-arterial O2 gradient increased from 19 [range 9 to 30] to 26 [range 20 to 34] kPa (P < 0.001) and remained elevated up to 6 hours after surgery. It rapidly declined again by 18 hours postoperatively. The observed increase in the pulmonary lactate release (PLR) from a baseline value of 0.022 [range -0.074 to 0.066] to 0.089 [range 0.016 to 0.209] mmol/min/m2 at six hours postoperatively did not reach statistical significance (P = 0.105). The systemic arterial lactate (Ls) concentration increased from 0.94 [range 0.78 to 1.06] to 1.39 [range 0.97 to 2.81] mmol/L (P < 0.001). The venoarterial pCO2 difference showed no significant change in comparison to baseline values. The mortality in the studied group was 2.5% (1/40). The pulmonary lactate production showed a statistically significant correlation with the systemic lactate concentration (R = 0.46; P = 0.003). Pulmonary injury following off pump myocardial revascularization was evidenced by a prompt increase in the alveolar-arterial oxygen gradient. The alveolar-arterial O2 gradient correlated with the duration of mechanical ventilation.