Lumivyöryjen aiheuttama eroosio ja kerrostumismuodot

Tiivistelmä. Lumivyöryt ovat jyrkillä rinteillä esiintyviä, pääasiassa lunta kuljettavia massaliikuntoja, jotka voivat kuitenkin kuljettaa lumimassan seassa myös debristä kuten kiviä ja orgaanista ainesta. Lumivyöryt voidaan luokitella irto- ja laattalumivyöryihin. Irtolumivyöryt ovat pistemäisestä lähteestä irtoavia ja alaspäin kasvavia lumivyöryjä. Laattalumivyöryissä lumipeitteestä irtoaa yhtenäinen laatta, kun siihen kohdistuva leikkausjännitys ylittää lumikerroksen leikkauslujuuden. Lumivyöryt kykenevät sekä erodoimaan maanpintaa että kerrostamaan kuljettamaansa ainesta erilaisiksi maaperämuodoiksi. Lumivyöryt aiheuttavat maanpinnan eroosiota edetessään lumettoman maanpinnan päällä tai lumivyörymassojen käsittäessä koko lumipeitteen. Tärkeimmät eroosiomekanismit ovat rakeiden törmäykset ja abraasio. Tiheästä aineksesta koostuvilla lumivyöryillä, kuten vesipitoisilla lumivyöryillä, on korkea eroosiopotentiaali. Lumivyöryjen aiheuttaman eroosion nopeus vaihtelee keskimäärin välillä 0–0,5 millimetriä vuodessa. Eroosiomuodoista, joita lumivyöryt synnyttävät, suurimpia ovat lumivyörykraatterit (engl. impact craters, impact pits), jotka ovat halkaisijaltaan 20–100 metriä, ja syvyydeltään 1–5 metriä olevia kraattereita, joiden distaalipuolella on usein puolikaaren muotoinen valli (engl. impact mound). Lineaarisia lumivyöryjen synnyttämiä eroosiomuotoja ovat lumivyörykourut (engl. avalanche chutes, avalanche furrows) ja laahausjäljet. Lumivyörykourut ovat muutamia metrejä leveitä ja 1–3 metriä syviä U-muotoisia uria. Näissä kouruissa ja lumivyöryuralla yleisesti voi esiintyä erisuuruisia lumivyöryn kuljettamien klastien maanpintaan synnyttämiä laahausjälkiä. Lumivyöryjen kuljettaman debriksen määrä vaihtelee hyvin suuresti. Lumivyöryjen kerrostamat sedimentit ovat lajittumattomia ja niiden kivet eivät ole suuntautuneita. Sedimenttien kerrostuminen siten, että perusmassa eli lumi sulaa muun aineksen ympäriltä aiheuttaa muun muassa klastien kerrostumista toistensa varaan, epävakaisiinkin asentoihin, ja pienten rakeiden sekä orgaanisen aineksen kerrostumista suurempien kivien ja lohkareiden päälle. Lumivyöryt kerrostavat pysähtymisvyöhykkeelleen pitkittäisiä, alaspäin leveneviä lumivyörykeiloja (engl. avalanche boulder tongues). Yleisesti satoja metrejä pitkät ja kymmenistä satoihin metriä leveät keilat koostuvat sorasta ja sitä karkeammista rakeista. Lumivyöryuralla esiintyy suurten lohkareiden distaalipuolella katvevalleja (engl. debris shadow, debris tail), jotka ovat pituudeltaan 10–15 metriä ja korkeudeltaan 0–1 metriä, ja jotka voivat olla alkuperältään sekä eroosion että kerrostumisen tulosta. Pienempiä pitkittäisiä kerrostumismuotoja ovat ruoteet (engl. ribs) ja reunavallit (engl. levées). Poikittaisia lumivyöryjen kerrostamia maaperämuotoja ovat törmäysharjanteet (engl. impact ramparts) ja pronival-muodostumat (engl. pronival ramparts, protalus ramparts). Törmäysharjanteet muodostuvat, kun lumivyöry törmää jokiuomaan singoten ja kerrostaen ainesta uoman distaalipuolelle poikittaiseksi harjanteeksi. Pronival-muodostumat ovat yleensä pysähtymisvyöhykkeellä esiintyviä matalia ja poikittaisia muodostamia, joita voivat synnyttää lumivyöryt, mutta myös muun muassa kivivyöryt ja solifluktio

Safety and immunogenicity of three doses of an eleven-valent diphtheria toxoid and tetanus protein – conjugated pneumococcal vaccine in Filipino infants

BACKGROUND: An 11-valent pneumococcal conjugate vaccine could provide significantly larger reduction in pneumococcal disease burden than the currently available 7-valent vaccine formulation in many countries. METHODS: In total, 50 infants were enrolled to this open, uncontrolled study, which evaluated the safety and immunogenicity of an aluminium adjuvanted 11-valent mixed-carrier diphtheria toxoid or tetanus protein-conjugated vaccine (11-PncTD) when administered in three doses at 6, 10 and 14 weeks of age simultaneously with DTwP//PRP-T and OPV vaccines in Filipino infants. RESULTS: The rates of local reactions between the two injection sites, those associated with the 11-PncTD vaccine and those with the DTwP//PRP-T were almost of equal frequency for all three vaccine doses except for induration, which was significantly more common in the DTP//PRP-T injection site. Fever was present in 39%, 22% and 21% of infants following each of the three doses. Antibody responses were determined by an enzyme immunoassay method before the first vaccination and after the three doses. The vaccine elicited a significant anti-pneumococcal polysaccharide antibody response against all serotypes included in the vaccine, except for type 14, for which the pre-vaccination geometric mean antibody concentration (GMC) was high (1.61 μg/ml). The GMCs one month after the vaccination series ranged from 1.1 micrograms/ml for type 6B to 23.4 μg/ml for type 4. CONCLUSION: The 11-PncTD vaccine is safe, well-tolerated and immunogenic. The effectiveness of the non-adjuvanted formulation of the vaccine in preventing pneumonia is currently being evaluated in the Philippines

Can Practical Nurses Identify Older Home Care Clients at Risk of Drug-Related Problems-Geriatricians' Appraisal of Their Risk Screenings: A Pilot Study

Background: Home care (HC) clients are increasingly older, have many chronic diseases, and use multiple medicines and thus are at high risk for drug-related problems (DRPs). Objective: Establish the sensitivity of practical nurse (PN) administered DRP risk assessment tool (DRP-RAT) compared with geriatrician's assessment of the medical record. Identify the clinically most significant DRPs needing action. Methods: Twenty-six PNs working in HC of Harkatie Health Center in Lieto, Finland, 46 HC clients (>= 65 years), and a geriatrician participated in this pilot study. The geriatrician reviewed HC clients' medications using 3 different methods. The reviews were based on the following: (1) the PN's risk screening (ie, PN-completed DRP-RAT) and medication list, (2) health center's medical records, and (3) methods 1 and 2 together. The main outcome was the number of "at-risk patients" (ie, the patient is at risk of clinically significant DRPs) by using each review method. Secondary outcomes were clinically most significant DRP-risk predicting factors identified by the geriatrician. Results: The geriatrician reviewed 45 clients' medications using all 3 methods. Based on PN-completed DRP-RAT and medication list, 93% (42/45) of the clients were classified as "at-risk patients." Two other review methods resulted in 45/45 (100%) "at-risk patients." Symptoms suggestive of adverse drug reactions were the most significant risk predicting factors. Small sample size limits the generalizability of the results. Conclusions: The PN-completed DRP-RAT was able to provide clinically important timely patient information for clinical decision making. DRP-RAT could make it possible to more effectively involve PNs in medication risk management among older HC clients

Respiratory diphtheria in an asylum seeker from Afghanistan arriving to Finland via Sweden, December 2015

In December 2015, an asylum seeker originating from Afghanistan was diagnosed with respiratory diphtheria in Finland. He arrived in Finland from Sweden where he had already been clinically suspected and tested for diphtheria. Corynebacterium diphtheriae was confirmed in Sweden and shown to be genotypically and phenotypically toxigenic. The event highlights the importance of early case detection, rapid communication within the country and internationally as well as preparedness plans of diphtheria antitoxin availability.Peer reviewe

Anatomical Differences Determine Distribution of Adenovirus after Convection-Enhanced Delivery to the Rat Brain

Background: Convection-enhanced delivery (CED) of adenoviruses offers the potential of widespread virus distribution in the brain. In CED, the volume of distribution (Vd) should be related to the volume of infusion (Vi) and not to dose, but when using adenoviruses contrasting results have been reported. As the characteristics of the infused tissue can affect convective delivery, this study was performed to determine the effects of the gray and white matter on CED of adenoviruses and similar sized super paramagnetic iron oxide nanoparticles (SPIO). Methodology/Principal Findings: We convected AdGFP, an adenovirus vector expressing Green Fluorescent Protein, a virus sized SPIO or trypan blue in the gray and white matter of the striatum and external capsule of Wistar rats and towards orthotopic infiltrative brain tumors. The resulting Vds were compared to Vi and transgene expression to SPIO distribution. Results show that in the striatum Vd is not determined by the Vi but by the infused virus dose, suggesting diffusion, active transport or receptor saturation rather than convection. Distribution of virus and SPIO in the white matter is partly volume dependent, which is probably caused by preferential fluid pathways from the external capsule to the surrounding gray matter, as demonstrated by co-infusing trypan blue. Distant tumors were reached using the white matter tracts but tumor penetration was limited. Conclusions/Significance: CED of adenoviruses in the rat brain and towards infiltrative tumors is feasible when regional anatomical differences are taken into account while SPIO infusion could be considered to validate proper catheter positioning and predict adenoviral distribution

Gene therapy for monogenic liver diseases: clinical successes, current challenges and future prospects

Over the last decade, pioneering liver-directed gene therapy trials for haemophilia B have achieved sustained clinical improvement after a single systemic injection of adeno-associated virus (AAV) derived vectors encoding the human factor IX cDNA. These trials demonstrate the potential of AAV technology to provide long-lasting clinical benefit in the treatment of monogenic liver disorders. Indeed, with more than ten ongoing or planned clinical trials for haemophilia A and B and dozens of trials planned for other inherited genetic/metabolic liver diseases, clinical translation is expanding rapidly. Gene therapy is likely to become an option for routine care of a subset of severe inherited genetic/metabolic liver diseases in the relatively near term. In this review, we aim to summarise the milestones in the development of gene therapy, present the different vector tools and their clinical applications for liver-directed gene therapy. AAV-derived vectors are emerging as the leading candidates for clinical translation of gene delivery to the liver. Therefore, we focus on clinical applications of AAV vectors in providing the most recent update on clinical outcomes of completed and ongoing gene therapy trials and comment on the current challenges that the field is facing for large-scale clinical translation. There is clearly an urgent need for more efficient therapies in many severe monogenic liver disorders, which will require careful risk-benefit analysis for each indication, especially in paediatrics