Modellazione bidimensionale della propagazione nell'entroterra della inondazione da mare negli scenari dei previsti cambiamenti climatici

Le ricerche di carattere eustatico, mareografico, climatico, archeologico e geocronologico, sviluppatesi soprattutto nell’ultimo ventennio, hanno messo in evidenza che gran parte delle piane costiere italiane risulta soggetta al rischio di allagamento per ingressione marina dovuta alla risalita relativa del livello medio del mare. Tale rischio è la conseguenza dell’interazione tra la presenza di elementi antropici e fenomeni di diversa natura, spesso difficilmente discriminabili e quantificabili, caratterizzati da magnitudo e velocità molto diverse tra loro. Tra le cause preponderanti che determinano l’ingressione marina possono essere individuati alcuni fenomeni naturali, climatici e geologici, i quali risultano fortemente influenzati dalle attività umane soprattutto a partire dal XX secolo. Tra questi si individuano: - la risalita del livello del mare, principalmente come conseguenza del superamento dell’ultimo acme glaciale e dello scioglimento delle grandi calotte continentali; - la subsidenza. Vaste porzioni delle piane costiere italiane risultano soggette a fenomeni di subsidenza. In certe zone questa assume proporzioni notevoli: per la fascia costiera emiliano-romagnola si registrano ratei compresi tra 1 e 3 cm/anno. Tale subsidenza è spesso il risultato della sovrapposizione tra fenomeni naturali (neotettonica, costipamento di sedimenti, ecc.) e fenomeni indotti dall’uomo (emungimenti delle falde idriche, sfruttamento di giacimenti metaniferi, escavazione di materiali per l’edilizia, ecc.); - terreni ad elevato contenuto organico: la presenza di depositi fortemente costipabili può causare la depressione del piano di campagna come conseguenza di abbassamenti del livello della falda superficiale (per drenaggi, opere di bonifica, emungimenti), dello sviluppo dei processi di ossidazione e decomposizione nei terreni stessi, del costipamento di questi sotto il proprio peso, della carenza di nuovi apporti solidi conseguente alla diminuita frequenza delle esondazioni dei corsi d’acqua; - morfologia: tra i fattori di rischio rientra l’assetto morfologico della piana e, in particolare il tipo di costa (lidi, spiagge, cordoni dunari in smantellamento, ecc. ), la presenza di aree depresse o comunque vicine al livello del mare (fino a 1-2 m s.l.m.), le caratteristiche dei fondali antistanti (batimetria, profilo trasversale, granulometria dei sedimenti, barre sommerse, assenza di barriere biologiche, ecc.); - stato della linea di costa in termini di processi erosivi dovuti ad attività umane (urbanizzazione del litorale, prelievo inerti, costruzione di barriere, ecc.) o alle dinamiche idro-sedimentarie naturali cui risulta soggetta (correnti litoranee, apporti di materiale, ecc. ). Scopo del presente studio è quello di valutare la probabilità di ingressione del mare nel tratto costiero emiliano-romagnolo del Lido delle Nazioni, la velocità di propagazione del fronte d’onda, facendo riferimento allo schema idraulico del crollo di una diga su letto asciutto (problema di Riemann) basato sul metodo delle caratteristiche, e di modellare la propagazione dell’inondazione nell’entroterra, conseguente all’innalzamento del medio mare . Per simulare tale processo è stato utilizzato il complesso codice di calcolo bidimensionale Mike 21. La fase iniziale di tale lavoro ha comportato la raccolta ed elaborazione mediante sistema Arcgis dei dati LIDAR ed idrografici multibeam , grazie ai quali si è provveduto a ricostruire la topo-batimetria di dettaglio della zona esaminata. Nel primo capitolo è stato sviluppato il problema del cambiamento climatico globale in atto e della conseguente variazione del livello marino che, secondo quanto riportato dall’IPCC nel rapporto del 2007, dovrebbe aumentare al 2100 mediamente tra i 28 ed i 43 cm. Nel secondo e terzo capitolo è stata effettuata un’analisi bibliografica delle metodologie per la modellazione della propagazione delle onde a fronte ripido con particolare attenzione ai fenomeni di breaching delle difese rigide ed ambientali. Sono state studiate le fenomenologie che possono inficiare la stabilità dei rilevati arginali, realizzati sia in corrispondenza dei corsi d’acqua, sia in corrispondenza del mare, a discapito della protezione idraulica del territorio ovvero dell’incolumità fisica dell’uomo e dei territori in cui esso vive e produce. In un rilevato arginale, quale che sia la causa innescante la formazione di breccia, la generazione di un’onda di piena conseguente la rottura è sempre determinata da un’azione erosiva (seepage o overtopping) esercitata dall’acqua sui materiali sciolti costituenti il corpo del rilevato. Perciò gran parte dello studio in materia di brecce arginali è incentrato sulla ricostruzione di siffatti eventi di rottura. Nel quarto capitolo è stata calcolata la probabilità, in 5 anni, di avere un allagamento nella zona di interesse e la velocità di propagazione del fronte d’onda. Inoltre è stata effettuata un’analisi delle condizioni meteo marine attuali (clima ondoso, livelli del mare e correnti) al largo della costa emiliano-romagnola, le cui problematiche e linee di intervento per la difesa sono descritte nel quinto capitolo, con particolare riferimento alla costa ferrarese, oggetto negli ultimi anni di continui interventi antropici. Introdotto il sistema Gis e le sue caratteristiche, si è passati a descrivere le varie fasi che hanno permesso di avere in output il file delle coordinate x, y, z dei punti significativi della costa, indispensabili al fine della simulazione Mike 21, le cui proprietà sono sviluppate nel sesto capitolo.

Bioremediation of PAHs - Limitations and soultions

Introduction 1.1 Occurrence of polycyclic aromatic hydrocarbons (PAH) in the environment Worldwide industrial and agricultural developments have released a large number of natural and synthetic hazardous compounds into the environment due to careless waste disposal, illegal waste dumping and accidental spills. As a result, there are numerous sites in the world that require cleanup of soils and groundwater. Polycyclic aromatic hydrocarbons (PAHs) are one of the major groups of these contaminants (Da Silva et al., 2003). PAHs constitute a diverse class of organic compounds consisting of two or more aromatic rings with various structural configurations (Prabhu and Phale, 2003). Being a derivative of benzene, PAHs are thermodynamically stable. In addition, these chemicals tend to adhere to particle surfaces, such as soils, because of their low water solubility and strong hydrophobicity, and this results in greater persistence under natural conditions. This persistence coupled with their potential carcinogenicity makes PAHs problematic environmental contaminants (Cerniglia, 1992; Sutherland, 1992). PAHs are widely found in high concentrations at many industrial sites, particularly those associated with petroleum, gas production and wood preserving industries (Wilson and Jones, 1993). 1.2 Remediation technologies Conventional techniques used for the remediation of soil polluted with organic contaminants include excavation of the contaminated soil and disposal to a landfill or capping - containment - of the contaminated areas of a site. These methods have some drawbacks. The first method simply moves the contamination elsewhere and may create significant risks in the excavation, handling and transport of hazardous material. Additionally, it is very difficult and increasingly expensive to find new landfill sites for the final disposal of the material. The cap and containment method is only an interim solution since the contamination remains on site, requiring monitoring and maintenance of the isolation barriers long into the future, with all the associated costs and potential liability. A better approach than these traditional methods is to completely destroy the pollutants, if possible, or transform them into harmless substances. Some technologies that have been used are high-temperature incineration and various types of chemical decomposition (for example, base-catalyzed dechlorination, UV oxidation). However, these methods have significant disadvantages, principally their technological complexity, high cost , and the lack of public acceptance. Bioremediation, on the contrast, is a promising option for the complete removal and destruction of contaminants. 1.3 Bioremediation of PAH contaminated soil & groundwater Bioremediation is the use of living organisms, primarily microorganisms, to degrade or detoxify hazardous wastes into harmless substances such as carbon dioxide, water and cell biomass Most PAHs are biodegradable unter natural conditions (Da Silva et al., 2003; Meysami and Baheri, 2003) and bioremediation for cleanup of PAH wastes has been extensively studied at both laboratory and commercial levels- It has been implemented at a number of contaminated sites, including the cleanup of the Exxon Valdez oil spill in Prince William Sound, Alaska in 1989, the Mega Borg spill off the Texas coast in 1990 and the Burgan Oil Field, Kuwait in 1994 (Purwaningsih, 2002). Different strategies for PAH bioremediation, such as in situ , ex situ or on site bioremediation were developed in recent years. In situ bioremediation is a technique that is applied to soil and groundwater at the site without removing the contaminated soil or groundwater, based on the provision of optimum conditions for microbiological contaminant breakdown.. Ex situ bioremediation of PAHs, on the other hand, is a technique applied to soil and groundwater which has been removed from the site via excavation (soil) or pumping (water). Hazardous contaminants are converted in controlled bioreactors into harmless compounds in an efficient manner. 1.4 Bioavailability of PAH in the subsurface Frequently, PAH contamination in the environment is occurs as contaminants that are sorbed onto soilparticles rather than in phase (NAPL, non aqueous phase liquids). It is known that the biodegradation rate of most PAHs sorbed onto soil is far lower than rates measured in solution cultures of microorganisms with pure solid pollutants (Alexander and Scow, 1989; Hamaker, 1972). It is generally believed that only that fraction of PAHs dissolved in the solution can be metabolized by microorganisms in soil. The amount of contaminant that can be readily taken up and degraded by microorganisms is defined as bioavailability (Bosma et al., 1997; Maier, 2000). Two phenomena have been suggested to cause the low bioavailability of PAHs in soil (Danielsson, 2000). The first one is strong adsorption of the contaminants to the soil constituents which then leads to very slow release rates of contaminants to the aqueous phase. Sorption is often well correlated with soil organic matter content (Means, 1980) and significantly reduces biodegradation (Manilal and Alexander, 1991). The second phenomenon is slow mass transfer of pollutants, such as pore diffusion in the soil aggregates or diffusion in the organic matter in the soil. The complex set of these physical, chemical and biological processes is schematically illustrated in Figure 1. As shown in Figure 1, biodegradation processes are taking place in the soil solution while diffusion processes occur in the narrow pores in and between soil aggregates (Danielsson, 2000). Seemingly contradictory studies can be found in the literature that indicate the rate and final extent of metabolism may be either lower or higher for sorbed PAHs by soil than those for pure PAHs (Van Loosdrecht et al., 1990). These contrasting results demonstrate that the bioavailability of organic contaminants sorbed onto soil is far from being well understood. Besides bioavailability, there are several other factors influencing the rate and extent of biodegradation of PAHs in soil including microbial population characteristics, physical and chemical properties of PAHs and environmental factors (temperature, moisture, pH, degree of contamination). Figure 1: Schematic diagram showing possible rate-limiting processes during bioremediation of hydrophobic organic contaminants in a contaminated soil-water system (not to scale) (Danielsson, 2000). 1.5 Increasing the bioavailability of PAH in soil Attempts to improve the biodegradation of PAHs in soil by increasing their bioavailability include the use of surfactants , solvents or solubility enhancers.. However, introduction of synthetic surfactant may result in the addition of one more pollutant. (Wang and Brusseau, 1993).A study conducted by Mulder et al. showed that the introduction of hydropropyl-ß-cyclodextrin (HPCD), a well-known PAH solubility enhancer, significantly increased the solubilization of PAHs although it did not improve the biodegradation rate of PAHs (Mulder et al., 1998), indicating that further research is required in order to develop a feasible and efficient remediation method. Enhancing the extent of PAHs mass transfer from the soil phase to the liquid might prove an efficient and environmentally low-risk alternative way of addressing the problem of slow PAH biodegradation in soil.

Early loading after 21 days of healing of nonsubmerged titanium implants with a chemically modified sandblasted and acid-etched surface: two-year results of a prospective two-center study

PURPOSE: The aim of this two-center study was to evaluate screw-type titanium implants with a chemically modified, sandblasted and acid-etched surface when placed in the posterior maxilla or mandible, and loaded 21 days after placement. MATERIAL AND METHODS: All 56 patients met strict inclusion criteria and provided informed consent. Each patient displayed either a single-tooth gap, an extended edentulous space, or a distal extension situation in the posterior mandible or maxilla. Eighty-nine dental implants (SLActive, Institut Straumann AG, Basel, Switzerland) were inserted according to an established nonsubmerged protocol and underwent undisturbed healing for a period of 21 days. Where appropriate, the implants were loaded after 21 days of healing with provisional restorations in full occlusion. Definitive metal ceramic restorations were fabricated and positioned on each implant after 6 months of healing. Clinical measurements regarding soft tissue parameters and radiographs were obtained at different time points up to 24 months after implant placement. RESULTS: Of the 89 inserted implants, two (2.2%) implants failed to integrate and were removed during healing, and two (2.2%) additional implants required a prolonged healing time. A total of 85 (95.6%) implants were therefore loaded without incident after 21 days of healing. No additional implant was lost throughout the study period, whereas one implant was lost to follow-up and therefore left unaccounted for further analysis. The remaining 86 implants all exhibited favorable radiographic and clinical findings. Based on strict success criteria, these implants were considered successfully integrated 2 years after insertion, resulting in a 2-year success rate of 97.7%. CONCLUSION: The results of this prospective two-center study demonstrate that titanium implants with a modified SLA surface can predictably achieve successful tissue integration when loaded in full occlusion 21 days after placement. Integration could be maintained without incident for at least 2 years of follow-up.

2010 International consensus algorithm for the diagnosis, therapy and management of hereditary angioedema

ABSTRACT:

Diagnostic value of animal-side antibody assays for rapid detection of Mycobacterium bovis or Mycobacterium microti infection in South American camelids

Tuberculosis (TB) in South American camelids (SAC) is caused by Mycobacterium bovis or Mycobacterium microti. Two serological methods, rapid testing (RT) and the dual-path platform (DPP) assay, were evaluated using naturally infected SAC. The study population included 156 alpacas and 175 llamas in Great Britain, Switzerland, and the United States. TB due to M. bovis (n = 44) or M. microti (n = 8) in 35 alpacas and 17 llamas was diagnosed by gross pathology examination and culture. Control animals were from herds with no TB history. The RT and the DPP assay showed sensitivities of 71% and 74%, respectively, for alpacas, while the sensitivity for llamas was 77% for both assays. The specificity of the DPP assay (98%) was higher than that of RT (94%) for llamas; the specificities of the two assays were identical (98%) for alpacas. When the two antibody tests were combined, the parallel-testing interpretation (applied when either assay produced a positive result) enhanced the sensitivities of antibody detection to 89% for alpacas and 88% for llamas but at the cost of lower specificities (97% and 93%, respectively), whereas the serial-testing interpretation (applied when both assays produced a positive result) maximized the specificity to 100% for both SAC species, although the sensitivities were 57% for alpacas and 65% for llamas. Over 95% of the animals with evidence of TB failed to produce skin test reactions, thus confirming concerns about the validity of this method for testing SAC. The findings suggest that serological assays may offer a more accurate and practical alternative for antemortem detection of camelid TB.

Thrombosis and drug-eluting stents: an objective appraisal

Stent thrombosis (ST) after percutaneous coronary intervention has been the focus of intense interest because of its attendant morbidity and mortality. There is controversy about several facets of the problem. These include the frequency of ST with drug-eluting stents (DES) versus bare-metal stents (BMS), the timing of the event, clinical consequences, risk factors, adjunctive therapy, and new preventive approaches. Information has accrued rapidly from several sources, including randomized controlled clinical trials of DES versus BMS in carefully selected subsets of patients and registry experiences in larger patient groups, which provide a more universal real-world picture. The results from these different data sets are not completely concordant. However, several general conclusions can be made: 1) ST is an infrequent but very severe complication of both BMS and DES; 2) at the present time, during 4 years of follow-up from randomized controlled trials that compared DES and BMS, there is no apparent difference in overall ST frequency, although the time course for occurrence appears to differ, with a relative numeric excess of ST late after DES implant; 3) despite this relative imbalance, no differences in the end points of death or death and infarction between DES and BMS are observed; 4) longer-term follow-up of these patients as well as larger angiographic and clinical subsets of patients who receive this technology outside of randomized trials are required to fully study this issue; and 5) advances in stent platforms for drug elution as well as adjunctive pharmacologic therapy are being evaluated to enhance long-term safety.

The Amplifier - v. 2, no. 14

In this issue...Dean Adami, M club, Red Rock, Bernice, Montana, Mineral Club, Mines Football, Sam Worcester, Professor Laity, Western Civilization class

The Amplifier - v. 4, no. 4

In this issue...Dean D. C. McAuliffe, Chelation, Copper Guards, March of Dimes, Ski Club, Coach Simonich, Sigma Rho, Anderson-Carlisle Society, Mineral Club

Past is Prologue: Montana’s Historic Women’s Movement Re-emerges in the Progressive 1970s -- Dorothy Bradley, Marilyn Wessel & Jane Jelinski “In the Crucible of Change”

One-hundred years ago, in 1914, male voters in Montana (MT) extended suffrage (voting rights) to women six years before the 19th Amendment to the US Constitution was ratified and provided that right to women in all states. The long struggle for women’s suffrage was energized in the progressive era and Jeanette Rankin of Missoula emerged as a leader of the campaign; in 1912 both major MT political party platforms supported women suffrage. In the 1914 election, 41,000 male voters supported woman suffrage while nearly 38,000 opposed it. MT was not only ahead of the curve on women suffrage, but just two years later in 1916 elected Jeanette Rankin as the first woman ever elected to the United States Congress. Rankin became a national leader for women's equality. In her commitment to equality, she opposed US entry into World War I, partially because she said she could not support men being made to go to war if women were not allowed to serve alongside them. During MT’s initial progressive era, women in MT not only pursued equality for themselves (the MT Legislature passed an equal pay act in 1919), but pursued other social improvements, such as temperance/prohibition. Well-known national women leaders such as Carrie Nation and others found a welcome in MT during the period. Women's role in the trade union movement was evidenced in MT by the creation of the Women's Protective Union in Butte, the first union in America dedicated solely to women workers. But Rankin’s defeat following her vote against World War I was used as a way for opponents to advocate a conservative, traditionalist perspective on women's rights in MT. Just as we then entered a period in MT where the “copper collar” was tightened around MT economically and politically by the Anaconda Company and its allies, we also found a different kind of conservative, traditionalist collar tightened around the necks of MT women. The recognition of women's role during World War II, represented by “Rosie the Riveter,” made it more difficult for that conservative, traditionalist approach to be forever maintained. In addition, women's role in MT agriculture – family farms and ranches -- spoke strongly to the concept of equality, as farm wives were clearly active partners in the agricultural enterprises. But rural MT was, by and large, the bastion of conservative values relative to the position of women in society. As the period of “In the Crucible of Change” began, the 1965 MT Legislature included only three women. In 1967 and 1969 only one woman legislator served. In 1971 the number went up to two, including one of our guests, Dorothy Bradley. It was only after the Constitutional Convention, which featured 19 women delegates, that the barrier was broken. The 1973 Legislature saw 9 women elected. The 1975 and 1977 sessions had 14 women legislators; 15 were elected for the 1979 session. At that time progressive women and men in the Legislature helped implement the equality provisions of the new MT Constitution, ratified the federal Equal Rights Amendment in 1974, and held back national and local conservatives forces which sought in later Legislatures to repeal that ratification. As with the national movement at the time, MT women sought and often succeeded in adopting legal mechanisms that protected women’s equality, while full equality in the external world remained (and remains) a treasured objective. The story of the re-emergence of Montana’s women’s movement in the 1970s is discussed in this chapter by three very successful and prominent women who were directly involved in the effort: Dorothy Bradley, Marilyn Wessel, and Jane Jelinski. Their recollections of the political, sociological and cultural path Montana women pursued in the 1970s and the challenges and opposition they faced provide an insider’s perspective of the battle for equality for women under the Big Sky “In the Crucible of Change.” Dorothy Bradley grew up in Bozeman, Montana; received her Bachelor of Arts Phi Beta Kappa from Colorado College, Colorado Springs, in 1969 with a Distinction in Anthropology; and her Juris Doctor from American University in Washington, D.C., in 1983. In 1970, at the age of 22, following the first Earth Day and running on an environmental platform, Ms. Bradley won a seat in the 1971 Montana House of Representatives where she served as the youngest member and only woman. Bradley established a record of achievement on environmental & progressive legislation for four terms, before giving up the seat to run a strong second to Pat Williams for the Democratic nomination for an open seat in Montana’s Western Congressional District. After becoming an attorney and an expert on water law, she returned to the Legislature for 4 more terms in the mid-to-late 1980s. Serving a total of eight terms, Dorothy was known for her leadership on natural resources, tax reform, economic development, and other difficult issues during which time she gained recognition for her consensus-building approach. Campaigning by riding her horse across the state, Dorothy was the Democratic nominee for Governor in 1992, losing the race by less than a percentage point. In 1993 she briefly taught at a small rural school next to the Northern Cheyenne Indian Reservation. She was then hired as the Director of the Montana University System Water Center, an education and research arm of Montana State University. From 2000 - 2008 she served as the first Gallatin County Court Administrator with the task of collaboratively redesigning the criminal justice system. She currently serves on One Montana’s Board, is a National Advisor for the American Prairie Foundation, and is on NorthWestern Energy’s Board of Directors. Dorothy was recognized with an Honorary Doctorate from her alma mater, Colorado College, was named Business Woman of the Year by the Bozeman Chamber of Commerce and MSU Alumni Association, and was Montana Business and Professional Women’s Montana Woman of Achievement. Marilyn Wessel was born in Iowa, lived and worked in Los Angeles, California, and Washington, D.C. before moving to Bozeman in 1972. She has an undergraduate degree in journalism from Iowa State University, graduate degree in public administration from Montana State University, certification from the Harvard University Institute for Education Management, and served a senior internship with the U.S. Congress, Montana delegation. In Montana Marilyn has served in a number of professional positions, including part-time editor for the Montana Cooperative Extension Service, News Director for KBMN Radio, Special Assistant to the President and Director of Communications at Montana State University, Director of University Relations at Montana State University and Dean and Director of the Museum of the Rockies at MSU. Marilyn retired from MSU as Dean Emeritus in 2003. Her past Board Service includes Montana State Merit System Council, Montana Ambassadors, Vigilante Theater Company, Montana State Commission on Practice, Museum of the Rockies, Helena Branch of the Ninth District Federal Reserve Bank, Burton K. Wheeler Center for Public Policy, Bozeman Chamber of Commerce, and Friends of KUSM Public Television. Marilyn’s past publications and productions include several articles on communications and public administration issues as well as research, script preparation and presentation of several radio documentaries and several public television programs. She is co-author of one book, 4-H An American Idea: A History of 4-H. Marilyn’s other past volunteer activities and organizations include Business and Professional Women, Women's Political Caucus, League of Women Voters, and numerous political campaigns. She is currently engaged professionally in museum-related consulting and part-time teaching at Montana State University as well as serving on the Editorial Board of the Bozeman Daily Chronicle and a member of Pilgrim Congregational Church and Family Promise. Marilyn and her husband Tom, a retired MSU professor, live in Bozeman. She enjoys time with her children and grandchildren, hiking, golf, Italian studies, cooking, gardening and travel. Jane Jelinski is a Wisconsin native, with a BA from Fontbonne College in St. Louis, MO who taught fifth and seventh grades prior to moving to Bozeman in 1973. A stay-at-home mom with a five year old daughter and an infant son, she was promptly recruited by the Gallatin Women’s Political Caucus to conduct a study of Sex-Role Stereotyping in K Through 6 Reading Text Books in the Bozeman School District. Sociologist Dr. Louise Hale designed the study and did the statistical analysis and Jane read all the texts, entered the data and wrote the report. It was widely disseminated across Montana and received attention of the press. Her next venture into community activism was to lead the successful effort to downzone her neighborhood which was under threat of encroaching business development. Today the neighborhood enjoys the protections of a Historic Preservation District. During this time she earned her MPA from Montana State University. Subsequently Jane founded the Gallatin Advocacy Program for Developmentally Disabled Adults in 1978 and served as its Executive Director until her appointment to the Gallatin County Commission in 1984, a controversial appointment which she chronicled in the Fall issue of the Gallatin History Museum Quarterly. Copies of the issue can be ordered through: http://gallatinhistorymuseum.org/the-museum-bookstore/shop/. Jane was re-elected three times as County Commissioner, serving fourteen years. She was active in the Montana Association of Counties (MACO) and was elected its President in 1994. She was also active in the National Association of Counties, serving on numerous policy committees. In 1998 Jane resigned from the County Commission 6 months before the end of her final term to accept the position of Assistant Director of MACO, from where she lobbied for counties, provided training and research for county officials, and published a monthly newsletter. In 2001 she became Director of the MSU Local Government Center where she continued to provide training and research for county and municipal officials across MT. There she initiated the Montana Mayors Academy in partnership with MMIA. She taught State and Local Government, Montana Politics and Public Administration in the MSU Political Science Department before retiring in 2008. Jane has been married to Jack for 46 years, has two grown children and three grandchildren.

Identification of small Sca-1(+), Lin(-), CD45(-) multipotential cells in the neonatal murine retina

OBJECTIVE: Bone marrow contains a subset of stem cells that give rise to nonhematopoietic lineages. These nonhematopoietic stem cells appear heterogeneous and contain cells committed to mesenchymal and endothelial lineages, as well as more primitive multipotential cells resembling progenitors of germ cells and very small embryonic/epiblast-like stem cells (VSELs). Nonhematopoietic stem cells can be mobilized from the bone marrow in response to tissue injury, and cells with similar properties have been found in cord blood and normal adult organs. However, the relationship between bone marrow cells and these adult organ stem cells is still unclear. The differentiation potential of some adult stem cells is organ-restricted, but other populations appear to retain multipotential capacity. MATERIALS AND METHODS: A population of small Sca-1(+), lineage-negative (Lin(-)), CD45(-) cells resembling VSELs were isolated from neonatal mouse retina by cell sorting. Differentiation of the cells in culture was achieved by exposure to embryonic stem cell differentiation protocols. RESULTS: VSEL-like cells comprise 1.5% of the neonatal mouse retina. They remain quiescent during retinal differentiation, and thus they do not contribute to normal retinal development. However, they display eye cell differentiation potential in culture and they are also multipotential and can give rise to cells representative of all three embryonic layers. CONCLUSIONS: The neonatal retina is an abundant postnatal source of multipotential VSEL-like cells that can differentiate in culture into a variety of lineages.