A tetracationic porphyrin with dual anti-prion activity

Prions are deadly infectious agents made of PrPSc, a misfolded variant of the cellular prion protein (PrPC) which self-propagates by inducing misfolding of native PrPC. PrPSc can adopt different pathogenic conformations (prion strains), which can be resistant to potential drugs, or acquire drug resistance, hampering the development of effective therapies. We identified Zn(II)-BnPyP, a tetracationic porphyrin that binds to distinct domains of native PrPC, eliciting a dual anti-prion effect. Zn(II)-BnPyP binding to a C-terminal pocket destabilizes the native PrPC fold, hindering conversion to PrPSc; Zn(II)-BnPyP binding to the flexible N-terminal tail disrupts N- to C-terminal interactions, triggering PrPC endocytosis and lysosomal degradation, thus reducing the substrate for PrPSc generation. Zn(II)-BnPyP inhibits propagation of different prion strains in vitro, in neuronal cells and organotypic brain cultures. These results identify a PrPC-targeting compound with an unprecedented dual mechanism of action which might be exploited to achieve anti-prion effects without engendering drug resistance

Immunopurification of Pathological Prion Protein Aggregates

Background: Prion diseases are fatal neurodegenerative disorders that can arise sporadically, be genetically inherited or acquired through infection. The key event in these diseases is misfolding of the cellular prion protein (PrP) into a pathogenic isoform that is rich in β-sheet structure. This conformational change may result in the formation of PrP, the prion isoform of PrP, which propagates itself by imprinting its aberrant conformation onto PrP molecules. A great deal of effort has been devoted to developing protocols for purifying PrP for structural studies, and testing its biological properties. Most procedures rely on protease digestion, allowing efficient purification of PrP27-30, the protease-resistant core of PrP. However, protease treatment cannot be used to isolate abnormal forms of PrP lacking conventional protease resistance, such as those found in several genetic and atypical sporadic cases. Principal Findings: We developed a method for purifying pathological PrP molecules based on sequential centrifugation and immunoprecipitation with a monoclonal antibody selective for aggregated PrP. With this procedure we purified full-length PrP and mutant PrP aggregates at electrophoretic homogeneity. PrP purified from prion-infected mice was able to seed misfolding of PrP in a protein misfolding cyclic amplification reaction, and mutant PrP aggregates from transgenic mice were toxic to cultured neurons. Significance: The immunopurification protocol described here isolates biologically active forms of aggregated PrP. These preparations may be useful for investigating the structural and chemico-physical properties of infectious and neurotoxic PrP aggregates

Reproductive biology of the crab Munida subrugosa (Decapoda: Anomura: Galatheidae) in the Beagle Channel, Argentina

Among the species of galatheids that occur in the southwestern Atlantic and coastal waters of Tierra del Fuego, Munida subrugosa (Decapoda: Anomura) is the most abundant one, especially in the Beagle Channel (55ºS, 68ºW). Galatheids have several commercial applications, and M. subrugosa could be of local and regional interest. However, the knowledge of its biology is still scarce. We sampled M. subrugosa monthly from November 1997 to November 1999 in the Beagle Channel by means of an epibenthic trawl. The reproductive cycle started in May, reflected by the occurrence of ovigerous females. Maximum size of oocytes, maximum value of gonadosomatic index in females (16.8 g·mm CL-1) and males (1.6 g·mm CL-1), and the proportion (~70%) of ovigerous females with full egg-clutches occurred in June. Since the proportion of ovigerous females in October was ~5% and the planktonic larvae reportedly hatch in September, the embryonic development lasted ~90120 days. Females and males attained physiological maturity at 9.9 and 8.0 mm CL respectively, and males reached morphometric maturity at 24.3 mm CL. Fecundity was correlated with female size (r =0.85) and was between 124 to 10,750 eggs per female. Average diameter of recently extruded eggs was 0.69 mm (SD=±0.06 mm). At the beginning of the reproductive cycle, ovigerous females had partial broods of ca. 300 eggs, which represented <5% of complete clutch

Description and key to the zoeal stages of the Campylonotidae (Decapoda, Caridea) from the Magellan region

The present work provides a first description of the zoeal stages of the Caridean prawns Campylonotus vagans, C. semistriatus and C. capensis Bate, 1888. Zoeal stages one and two were obtained from plankton catches during several expeditions in the Magellan region and the southwestern Atlantic Ocean, and first zoeae of C. vagans were confirmed with larvae hatched in a laboratory culture. Based on the results obtained, we conclude the morphological differences of the presence/absence of carapace spines, the shape of the somites, the telson and its number of posterolateral spines to serve as diagnostic features for the determination of campylonotid larvae. Morphological comparisons with larvae of the Pandalidae, Palaemonidae, and Oplophoridae suggest the Campylonotidae to be phylogenetically related to the Oplophoridae. Additionally, a key for identifying the zoeal stages of the Campylonotidae from the southernmost region of America is given in order to facilitate future ecological and life history studies.<br/

The natural northern European boreal forests : unifying the concepts, terminologies, and their application

Munida subrugosa is the most abundant galatheid crab species in the Beagle Channel (55°S 68°W) off Tierra del Fuego, Argentina. Samples of crabs and the epibenthic community were taken on a monthly basis at two different depth strata (70m), by means of epibenthic trawling from 1998 to 1999. Stomach contents from 1582 crabs were analysed, out of which only 2% had empty stomachs. The quantity of food in the stomach contents was clearly seasonal and similar at both depths. The organic matter varied throughout the year and between both depths, being significantly higher in summer/spring than in autumn/winter. Munida subrugosa shows two different and simultaneous feeding habits: (1) as a predator M. subrugosa feeds on crustaceans, algae, and polychaetes; and (2) as a deposit feeder M. subrugosa consumes particulate organic matter and organisms associated with the superficial layer of of the sediment. The composition of the diet of Munida subrugosa was similar for both years, and independent of depth, sex or season. Munida subrugosa selected crustaceans only in autumn and winter, whereas most food items were found according to their availability in the habitat

Distribution, reproductive and energetic conditions of decapod crustaceans along the Scotia Arc (Southern Ocean)

Studies on decapod distribution patterns and reproductive and energetic conditions were carried out along the islands and shallows of the Scotia Arc (Southern Ocean) during the RV “Polarstern” LAMPOS expedition (ANT XIX/5) between April and May 2002. A clear biogeographic zonation was found. The Subantarctic Magellan-South Atlantic decapod fauna consisting of both “natant” (caridean) and “reptant” (astacidean, anomuran, and brachyuran) decapods appeared along the northern branch of the Scotia Arc to South Georgia, where Subantarctic and Antarctic faunas were found overlapping. An impoverished caridean shrimp fauna was found along the islands of the southern branch, from the South Sandwich Islands to the Antarctic Peninsula. Differences in the reproductive traits of the two most abundant species were detected. The reproductive cycle of Notocrangon antarcticus at South Georgia was more advanced than that at the South Orkney Islands, probably due to temperature differences between the two locations. Although the oogenesis and the reproductive cycle of Munida subrugosa seem to be in phase at Burdwood Bank and in the Beagle Channel, the oocyte number is probably lower at the former location. A new index was used to measure the energy devoted to reproduction by relating the energy contents of the egg mass/ovary plus hepatopancreas and the energy content of the whole body. This index revealed that the energy investment in reproduction was (1) independent of the sampling location, (2) species-specific, and (3) larger in caridean shrimps than in galatheid crabs

Dual effects of 9-cis retinoic acid on ACTH-dependent hyperplastic adrenal tissues

Retinoids play a pivotal role in adrenal development and differentiation. Recent clinical trials revealed therapeutic potential of both all-trans and 9-cis retinoic acid in patients with cortisol excess due to a pituitary ACTH-secreting adenoma and indicated that retinoids might act also on the adrenal. Aim of the present study was to evaluate the effect of 9-cis retinoic acid on adrenals from patients with ACTH-dependent Cushing\u2019s syndrome. Adrenal specimens from six patients with Cushing\u2019s disease were incubated with 10\ua0nM\u20131\ua0\ub5M 9-cis retinoic acid with and without 10\ua0nM ACTH. Cortisol secretion was measured by immunoassay and expression of genes involved in steroidogenesis as well as retinoic acid action were evaluated by real-time RT-PCR. Incubation with 10\u2013100\ua0nM 9-cis retinoic acid increased spontaneous cortisol secretion and expression of STAR and CYP17A. On the other hand, in wells treated with ACTH, 9-cis retinoic acid markedly diminished ACTH receptor upregulation and no stimulatory effect on cortisol secretion or steroidogenic enzyme synthesis was observed. ACTH itself increased ligand-induced retinoic acid receptor expression, possibly enhancing sensitivity to retinoic acid. Our findings indicate that the effect of 9-cis retinoic acid in presence of ACTH is distinct from unchallenged wells and support the hypothesis of a direct adrenal action in patients with Cushing\u2019s disease

Use of thermography (IRT) as a pre-diagnostic technique in bovine mastitis: a pilot study

The bovine mastitis is one of the major sources for Italian dairy farms. Goal of this work is to verify if it is possible use infrared thermography (IRT) as a non-invasive tool for the early diagnosis of subclinical mastitis. Udder skin temperature has been detected both from the lateral (TL) than from the rear of the breast (TP). 380 Holstein cows from 3 different farms in the North of Italy were selected. A portable infrared camera G120EX with microbolometer sensor (320 x 240 pixels) was used. The measurements carried out concurrently with monthly DHI control performed by local Breeders Association during the summer in 2016. Somatic cell count SCC in milk is approved as marker to assess inflammation; a cutoff of 200,000 cell/mL was used to settle infected cows. Udder temperature values obtained by IRT were compared with those of SCC given from DHI control using a statistical software (SPSS 24.0). The SCC was correlated with the maximum temperature of the udder taken laterally TL (p 200.000 cell/mL), the average value of TP was 38.5 \ub1 0.8 \ub0C and that of TL was 38.3 \ub1 1.0 \ub0C. In healthy animals (SCC <200.000), average value of TP was equal to 38.6 \ub1 0.8 \ub0C and that of TL was equal to 38.6 \ub1 0.8 \ub0C. Increasing the number of subjects is necessary to confirm the data obtained and investigate the meaning of a negative correlation factor