Kinetics of Protein-Protein Interactions of Connexins: Use of Enzyme Linked Sorbent Assays

Determination of the protein-protein interactions of connexins has become a rapidly expanding field of research. While there are multiple methods of determining the identity of binding partners, determination of the strengths of interactions is not as simple. Here we describe the use of the in vitro method Enzyme Linked Sorbent Assay (ELSA) to compare binding affinities of known protein partners for Connexin43. We used the binding of Cx43 Carboxyl Terminal domain to the PDZ-2 domain of Zonula Occludens-1 and to the SH3 domain of c-Src. In the ELSA assay we found that while the binding of the SH3 domain of c-Src is pH-dependent, the interaction of the PDZ domain of ZO-1 is not. These data confirm findings using Surface Plasmon Resonance (1) and indicate that ELSA can be a useful tool in determining the kinetics of protein-protein interactions.     

Distribution,habitat affinities and phenology of the <Emphasis Type="Italic">Micrargus herbigradus</Emphasis>-species group (Araneae: Linyphiidae) in Poland

We review the known information on the distribution and habitat affinities of the Micrargus herbigradus-species group in Poland. The analysis is based on a thorough literature survey, our own materials, and verification of some older collections. We give new diagnostic drawings and review the characters that are useful in identification of species within the group. Three species are present in Poland: M. herbigradus (Blackwall, 1854), M. apertus (O.-P. Cambridge, 1870) and M. georgescuae Millidge, 1976. The latter is recorded for the first time in the country, and we add numerous new localities for the two former species. Micrargus herbigradus is common and widespread in Poland, living in various habitats, with only a slight preference to forests. In contrast, M. apertus is widely distributed but rarely found, while its affinity to forests is the highest within the group. The records of this species are most numerous in lowland forests (up to c. 300 m a.s.l), but it can also be found at higher altitudes. M. georgescuae is found only in montane habitats, both in the Sudetes and the Carpathian Mountains, from above 650 m a.s.l. The adults of all three species occur the whole year round, but seem to be most abundant in May and June.     

ERRγ Promotes Angiogenesis,Mitochondrial Biogenesis,and Oxidative Remodeling in PGC1α/β-Deficient Muscle

1. Download high-res image (149KB)
2. Download full-size image

     

The molecular and phenotypic characterization of fructophilic lactic acid bacteria isolated from the guts of <Emphasis Type="Italic">Apis mellifera</Emphasis> L. derived from a Polish apiary

This paper describes taxonomic position, phylogeny, and phenotypic properties of 14 lactic acid bacteria (LAB) originating from an Apis mellifera guts. Based on the 16S rDNA and recA gene sequence analyses, 12 lactic acid bacteria were assigned to Lactobacillus kunkeei and two others were classified as Fructobacillus fructosus. Biochemically, all isolated lactic acid bacteria showed typical fructophilic features and under anaerobic conditions grew well on fructose, but poorly on glucose. Fast growth of bacteria on glucose was noted in the presence of oxygen or fructose as external electron acceptors. The residents of honeybee guts were classified as heterofermentative lactic acid bacteria. From glucose, they produced almost equimolar amounts of lactic acid, acetic acid, and trace amounts of ethanol. Furthermore, they inhibited the growth of the major honeybee pathogen, Paenibacillus larvae, meaning that the LAB studied may have the health-conferring properties of probiotics.     

A new neolignan glucoside from hairy roots of Cichorium intybus

A new neolignan glucoside was isolated from hairy roots of Cichorium intybus. Its structure was determined as (7S, 8R)-3′-demethyl-dehydrodiconiferyl alcohol-3′-O-β-glucopyranoside based on a combination of 1D and 2D NMR techniques and CD data. In addition, further water soluble constituents, including four known phenolic compounds and one known sesquiterpene lactone glucoside, were isolated from the same source.     

Complete Genome and Molecular Epidemiological Data Infer the Maintenance of Rabies among Kudu (Tragelaphus strepsiceros) in Namibia

Rabies in kudu is unique to Namibia and two major peaks in the epizootic have occurred since it was first noted in 1977. Due to the large numbers of kudu that were affected, it was suspected that horizontal transmission of rabies occurs among kudu and that rabies was being maintained independently within the Namibian kudu population – separate from canid cycles, despite geographic overlap. In this study, it was our aim to show, through phylogenetic analyses, that rabies was being maintained independently within the Namibian kudu population. We also tested, through complete genome sequencing of four rabies virus isolates from jackal and kudu, whether specific mutations occurred in the virus genome due to host adaptation. We found the separate grouping of all rabies isolates from kudu to those of any other canid species in Namibia, suggesting that rabies was being maintained independently in kudu. Additionally, we noted several mutations unique to isolates from kudu, suggesting that these mutations may be due to the adaptation of rabies to a new host. In conclusion, we show clear evidence that rabies is being maintained independently in the Namibian kudu population – a unique phenomenon with ecological and economic impacts.     

Insulinoma--diagnosis and treatment

Insulinomas are the most common functioning endocrine tumors of pancreas. Approximately 10% are multiple, less than 10% can be malignant and 5-10% associated with the MEN-1 syndrome. Insulinomas are the most common cause of hypoglycemia resulting from endogenous hyperinsulinism. The aim of this lecture is to present the up-to-date information concerning the prevalence, diagnosis and treatment of insulinoma.     

Octreotide suppression test in diagnosing and predicting the outcome of therapy in patients with neuroendocrine tumors. Preliminary report

INTRODUCTION: Chromogranin A (CgA) is a non-specific marker of neuroendocrine tumors (NET) and is important in monitoring the disease course and NET treatment. AIM OF THE STUDY: Usefulness of suppression test of CgA secretion with octreotide in diagnosis and predicting the therapy outcome in NET patients. MATERIAL AND METHODS: The study included 32 patients with NET of gastrointestinal tract, lung and of unknown origin. CgA level in blood plasma on fasting, before and 30, 60, 90 and 120 minutes after subcutaneous administration of 100 mug octreotide, was determined in all patients. The subjects were divided into two subgroups with relation to CgA level and to the results of somatostatin receptor scintigraphy (SRS). RESULTS: Statistically significant CgA decrease after octreotide administration in all study time points and positive results of SRS were found in the patients with the elevated CgA level. No statistically significant decrease of CgA level after octreotide was found in the group with normal CgA levels. In this group, 13 patients had a negative result of SRS, and somatostatin receptors expression was found in one patient. Tolerance of somatostatin analogs (SSA) therapy was very good. CONCLUSIONS: Octreotide suppression test with CgA level assessment in NET patients is a simple, straightforward examination, providing information on the predicted response to the applied SSA and the data on initial clinical tolerance of those agents. This examination can also be a screening test useful in planning the treatment with SSA in patients with NET.