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1.
Rev Biol Trop ; 61(3): 1133-56, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24027913

RESUMO

A total of 45 native Costa Rican tree species are threatened or in danger of extinction, but the Convention on International Trade Endangered Species (CITES) includes only eight of these in its Appendices. However, the identification of other species based on their wood anatomy is limited. The present study objective was to describe and to compare wood anatomy and fluorescence activity in some endangered or threatened species of Costa Rica. A total of 45 (22 endangered and 23 threatened with extinction) wood samples of these species, from the xylaria of the Instituto Tecnológico de Costa Rica and the Forest Products Laboratory in Madison, Wisconsin, were examined. Surface fluorescence was positive in eight species, water extract fluorescence was positive in six species and ethanol extract fluorescence was positive in 24 species. Almost all species were diffuse porous except for occasional (Cedrela odorata, C. fissilis, Cordia gerascanthus) or regular (C. salvadorensis and C. tonduzii) semi-ring porosity. A dendritic vessel arrangement was found in Sideroxylon capari, and pores were solitary in Guaiacum sanctum and Vantanea barbourii. Vessel element length was shortest in Guaiacum sanctum and longest in Humiriastrum guianensis, Minquartia guianensis and Vantanea barbourii. Finally, anatomical information and fluorescence activity were utilized to construct an identification key of species, in which fluorescence is a feature used in identification.


Assuntos
Espécies em Perigo de Extinção , Árvores/classificação , Madeira/anatomia & histologia , Costa Rica , Fluorescência , Árvores/anatomia & histologia
2.
Am J Bot ; 99(6): 1010-9, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22575368

RESUMO

PREMISE OF THE STUDY: Pioneer species of tropical trees allocate wood specific gravity (SG) differently across the radius. Some species exhibit relatively uniform, low SG wood, whereas many others exhibit linear increases in SG across the radius. Here, we measured changes in SG across the radius of Schizolobium parahyba (Fabaceae-Caesalpinioideae), a wide-ranging, neotropical pioneer, used extensively in land reclamation and forest restoration in Brazil. METHODS: Pith-to-bark radial wood cores were extracted with increment borers from 42 trees at five sites, in Central and South America. Cores were cut into 1-cm segments whose specific gravities were determined and analyzed via linear and nonlinear regression. Wood specific gravity, very low initially at 0.15-0.20, doubled or tripled across the tree radius to 0.45-0.65 for large adults. KEY RESULTS: Unlike linear increases in other tropical pioneers, the increases in Schizolobium were nonlinear (convex up). At one site with even-aged trees, the magnitude of the radial increase was similar in all trees, despite a 4-fold difference in diameter among trees, implying that the radial increases in Schizolobium were regulated by tree age, not by tree size. CONCLUSIONS: This unique pattern of development should provide an extended period of growth when SG is low, facilitating hyper-extension of the bole, at some risk of structural failure. Later in growth, the SG rate of increase accelerates, reinforcing what was a precarious bole. Overall, these results suggest a third model for xylem allocation in tropical trees, a model that may be associated with monopodial stem development and limited life span.


Assuntos
Fabaceae/crescimento & desenvolvimento , Árvores/crescimento & desenvolvimento , Madeira/crescimento & desenvolvimento , Xilema/crescimento & desenvolvimento , Algoritmos , Brasil , Agricultura Florestal/métodos , Geografia , Modelos Lineares , Modelos Biológicos , Fatores de Tempo , Clima Tropical
3.
Nature ; 426(6966): 549-52, 2003 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-14654838

RESUMO

Afro-Arabian mammalian communities underwent a marked transition near the Oligocene/Miocene boundary at approximately 24 million years (Myr) ago. Although it is well documented that the endemic paenungulate taxa were replaced by migrants from the Northern Hemisphere, the timing and evolutionary dynamics of this transition have long been a mystery because faunas from about 32 to 24 Myr ago are largely unknown. Here we report a late Oligocene fossil assemblage from Ethiopia, which constrains the migration to postdate 27 Myr ago, and yields new insight into the indigenous faunal dynamics that preceded this event. The fauna is composed of large paenungulate herbivores and reveals not only which earlier taxa persisted into the late Oligocene epoch but also demonstrates that one group, the Proboscidea, underwent a marked diversification. When Eurasian immigrants entered Afro-Arabia, a pattern of winners and losers among the endemics emerged: less diverse taxa such as arsinoitheres became extinct, moderately species-rich groups such as hyracoids continued into the Miocene with reduced diversity, whereas the proboscideans successfully carried their adaptive radiation out of Afro-Arabia and across the world.


Assuntos
Biodiversidade , Fósseis , Mamíferos , Migração Animal , Animais , Arábia , Ásia , Evolução Biológica , Etiópia , Europa (Continente) , Sedimentos Geológicos , Mamíferos/anatomia & histologia , Mamíferos/classificação , Dente/anatomia & histologia
4.
J Econ Entomol ; 113(3): 1183-1194, 2020 06 06.
Artigo em Inglês | MEDLINE | ID: mdl-32304325

RESUMO

Although international regulations have been successfully implemented to reduce the introduction and spread of plant pests through wood packaging material (WPM), wood-boring insects continue to be intercepted in WPM at U.S. ports of entry. Both hardwoods and softwoods are used in the construction of WPM for international trade; however, it is not clear if some types of wood pose higher risks than others for harboring wood borers. This study documented the taxonomic diversity of infested wood genera intercepted as a result of targeted WPM inspection at U.S. ports, and identified many of the wood-boring insects transported within them. The results of this study reveal associations among packaging woods, commodities, and shipment origins. The wood genera most frequently infested were Pinus Linnaeus (Pinales: Pinaceae), Picea Miller (Pinales: Pinaceae), and Populus Linnaeus (Malpighiales: Salicaceae), which were heavily represented as packaging for commodities such as stone, metal, vehicles, and machinery. In addition to these results, we summarized preferences by the wood borers to develop in living, stressed, dying, or dead hosts, the pest status of intercepted wood borers in their native and non-native ranges, and potential host range of intercepted wood borers to gauge potential for these taxa to become pests in North America. New possible host associations are reported for eight wood borer taxa. Taxonomy of host wood is presented as a new factor for consideration in pathway-level risk analysis of WPM, and the findings further reinforce the need for enhanced compliance with ISPM 15 to reduce entry of non-native wood-boring insects.


Assuntos
Besouros , Madeira , Animais , Comércio , Insetos , Internacionalidade , América do Norte , Árvores
5.
Cancer Biother Radiopharm ; 21(2): 130-7, 2006 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16706633

RESUMO

OBJECTIVE: We conducted a phase II trial in metastatic renal cell cancer of outpatient subcutaneous (s.c.) interferon-alpha2b (IFN), followed by an inpatient hybrid schedule of bolus and continuous interleukin-2 (IL- 2). METHODS: Treatment consisted of monthly IFN 10 MU/m(2) s.c. for 4 consecutive days, followed by 36 MIU/m(2) bolus IL-2, then 72-hour continuous intravenous (i.v.) infusion of 18 MIU/m(2) IL-2 per day. Between May 1997 and June 2000, 25 men and 11 women enrolled, with a median age of 57 years (range, 42-77), including 9 patients over 65. Prior treatment included nephrectomy (31), radiation (8), biotherapy (7), and chemotherapy (4). Sites of disease included 26 lung, 13 lymph node, 9 bone, 8 liver, 4 kidney, and 4 adrenal locations. Patients received an average of 3.1 treatment cycles (range, 1-6). RESULTS: There was 1 complete and 3 partial responses, for a response rate of 11% (3% to 27%; 95% confidence interval [CI]); 40% had stable disease. Median failure-free survival was 2.5 months; median overall survival was 15.0 months. The 1-, 2-, and 5-year survival rates were 53%, 30%, and 12%, respectively. Only 8 patients required a reduction in IL-2 dose. The most frequent grade 3 or 4 toxicities were 11% fatigue, 9% renal insufficiency, and 7% hypotension. CONCLUSIONS: Response and survival rates were similar to those seen in other multicenter trials using inpatient high-dose IL-2.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Carcinoma de Células Renais/tratamento farmacológico , Neoplasias Renais/tratamento farmacológico , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Carcinoma de Células Renais/patologia , Esquema de Medicação , Feminino , Humanos , Infusões Intravenosas , Injeções Subcutâneas , Interferon alfa-2 , Interferon-alfa/administração & dosagem , Interferon-alfa/efeitos adversos , Interleucina-2/administração & dosagem , Interleucina-2/efeitos adversos , Neoplasias Renais/patologia , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica , Proteínas Recombinantes
6.
Cancer Biother Radiopharm ; 17(2): 165-73, 2002 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-12030110

RESUMO

BACKGROUND: The treatment of metastatic renal cell cancer remains unsatisfactory despite encouraging results with biotherapy. Pilot studies from other investigators have suggested that combining cis-retinoic acid and 5-fluorouracil (5FU) with interleukin-2 (IL-2) and interferon-alpha (IFN) may improve outcomes for such patients. METHODS: Eligible patients had metastatic renal cell cancer, were in good medical condition, and had not been treated previously with more than two of the study agents. A 56-day treatment cycle consisted of: interferon-alpha 2a 3.0 mu/m2 s.c. Monday, Wednesday, and Friday weeks 1-8, interleukin-2 11 mu/m2 s.c. Tuesday, Thursday and Saturday of weeks 1-4, cis-retinoic acid 1 mg/kg p.o. daily weeks 1-8, and 5-FU 750 mg/m2 i.v. weekly during weeks 5-8. Patients were evaluated for tumor response every 8 weeks, and in the absence of tumor progression, patients could receive treatment for up to one year. Survival was determined from the first date of treatment. RESULTS: The 58 renal cell carcinoma patients included 41 men and 17 women, with a median age of 57 years with a range of 28-85 who were enrolled between October 1994 and July 1997. Thirty-seven percent were asymptomatic when treatment was initiated. Sites of disease at study entry included 62% lung, 34% bone, 31% lymph node, 22% kidney, 16% liver and 10% adrenal. There were only three patients with significant tumor responses (one complete, two partial) for a response rate of 5% (0-11% 95% CI) based on intent-to-treat analysis, and 6% (0-12%, 95% CI) for the 53 patients who were evaluable for response. The response rate among evaluable nephrectomized patients who had received no prior radiation or systemic treatment was 3/25 (12%). The median failure-free survival was 2.8 months; median overall survival was 10.9 months. The 1-year survival rate was 50% and 2-year survival rate was 33%. The most frequent toxicities were fatigue-81% (26% grade 3 or 4), nausea/vomiting-59%, and leukopenia/neutropenia 57% (16% grade 3 or 4). CONCLUSION: Despite a disappointing objective response rate, survival in these patients who were treated entirely as outpatients was similar to that seen in our earlier trials of inpatient, intermediate dose continuous infusion IL-2-based therapy.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma de Células Renais/tratamento farmacológico , Neoplasias Renais/tratamento farmacológico , Adulto , Idoso , Idoso de 80 Anos ou mais , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Carcinoma de Células Renais/mortalidade , Carcinoma de Células Renais/patologia , Feminino , Fluoruracila/administração & dosagem , Humanos , Injeções Subcutâneas , Interferon alfa-2 , Interferon-alfa/administração & dosagem , Interleucina-2/administração & dosagem , Neoplasias Renais/mortalidade , Neoplasias Renais/patologia , Masculino , Pessoa de Meia-Idade , Proteínas Recombinantes , Taxa de Sobrevida , Resultado do Tratamento , Tretinoína/administração & dosagem
7.
Am J Bot ; 97(3): 519-24, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21622413

RESUMO

The specific gravity (SG) of wood is a measure of the amount of structural material a tree species allocates to support and strength. In recent years, wood specific gravity, traditionally a forester's variable, has become the domain of ecologists exploring the universality of plant functional traits and conservationists estimating global carbon stocks. While these developments have expanded our knowledge and sample of woods, the methodologies employed to measure wood SG have not received as much scrutiny as SG's ecological importance. Here, we reiterate some of the basic principles and methods for measuring the SG of wood to clarify past practices of foresters and ecologists and to identify some of the prominent errors in recent studies and their consequences. In particular, we identify errors in (1) extracting wood samples that are not representative of tree wood, (2) differentiating wood specific gravity from wood density, (3) drying wood samples at temperatures below 100°C and the resulting moisture content complications, and (4) improperly measuring wood volumes. In addition, we introduce a new experimental technique, using applied calculus, for estimating SG when the form of radial variation is known, a method that significantly reduces the effort required to sample a tree's wood.

8.
Am J Bot ; 96(6): 1108-15, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21628261

RESUMO

One method to determine past climate has been the use of leaf morphological characteristics of fossil leaves quantified using modern climate and canopy leaf characteristics. Fossil assemblages are composed of abscised leaves, and climate may be more accurately determined by using leaves from leaf litter instead of the canopy. To better understand whether taphonomic processes make a difference in this relationship, a north-central Florida woodland was sampled to determine the morphologically based climate estimates from these leaves. Leaves from woody, dicotyledonous plants were collected and identified, then compared using presence/absence data and analyzed using several linear regression equations and the CLAMP data set. Although the majority of standing vegetation was reflected in leaf litter, some inconsistencies were observed, which may reflect plant community structure or sampling technique. Mean annual temperature (MAT) and growing season precipitation (GSP) were estimated from leaf litter morphological characters and living leaves. Overall, values for MAT estimated from litter and living leaves were cooler than actual MATs, although several accurate and high estimates were obtained depending on the predictive method used. Estimated GSP values were higher than actual GSPs. Statistically, no difference was observed between MAT and GSP estimates derived from leaf litter vs. estimates derived from living leaves, with one exception.

9.
Rev. biol. trop ; 61(3): 1113-1156, sep. 2013. ilus, tab
Artigo em Inglês | LILACS | ID: lil-688465

RESUMO

A total of 45 native Costa Rican tree species are threatened or in danger of extinction, but the Convention on International Trade Endangered Species (CITES) includes only eight of these in its Appendices. However, the identification of other species based on their wood anatomy is limited. The present study objective was to describe and to compare wood anatomy and fluorescence activity in some endangered or threatened species of Costa Rica. A total of 45 (22 endangered and 23 threatened with extinction) wood samples of these species, from the xylaria of the Instituto Tecnológico de Costa Rica and the Forest Products Laboratory in Madison, Wisconsin, were examined. Surface fluorescence was positive in eight species, water extract fluorescence was positive in six species and ethanol extract fluorescence was positive in 24 species. Almost all species were diffuse porous except for occasional (Cedrela odorata, C. fissilis, Cordia gerascanthus) or regular (C. salvadorensis and C. tonduzii) semi-ring porosity. A dendritic vessel arrangement was found in Sideroxylon capari, and pores were solitary in Guaiacum sanctum and Vantanea barbourii. Vessel element length was shortest in Guaiacum sanctum and longest in Humiriastrum guianensis, Minquartia guianensis and Vantanea barbourii. Finally, anatomical information and fluorescence activity were utilized to construct an identification key of species, in which fluorescence is a feature used in identification.


Un total de 45 especies de árboles de Costa Rica se catalogaron como amenazadas o en peligro de extinción, de las cuales, CITES (Convention on International Trade Endangered Species) incluye solamente ocho en sus Apéndices. Sin embargo, la identificación de las especies basadas en su anatomía es muy limitada. El presente estudio tiene el objetivo describir y comparar la anatomía y la fluorescencia de las especies amenazadas o en peligro de extinción de Costa Rica. Muestras de madera de las especies en peligro de extinción o amenazadas de la xiloteca del Instituto Tecnológico de Costa Rica y del Laboratorio de Productos Forestales de los Estados Unidos en Wisconsin se examinaron, se describió su anatomía, se evaluó su actividad fluorescente y se midió su densidad. La superficie de la madera fue fluorescente en ocho especies, el extracto en agua fue fluorescente en seis especies y el extracto en etanol fue positivo en 24 especies. Muchas de las especies presentaban porosidad difusa, excepto algunas Cedrela odorata, C. fissilis, Cordia gerascanthus C. salvadorensis y C. tonduzii que presentaban porosidad semi-anular. Vasos con distribución déndrica se encontró en Sideroxylon capari y poros solitarios en Guaiacum sanctum y Vantanea barbourii. Los vasos más cortos se encontraron en Guaiacum sanctum y los vasos más largos en Humiriastrum guianensis, Minquartia guianensis y Vantanea barbourii. Finalmente, la información de la anatomía y de su fluorescencia se utilizó para construir una clave de identificación, donde la actividad de fluorescencia juega un papel importante en la identificación.


Assuntos
Espécies em Perigo de Extinção , Árvores/classificação , Madeira/anatomia & histologia , Costa Rica , Fluorescência , Árvores/anatomia & histologia
10.
Ther Apher ; 6(1): 5-14, 2002 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11886571

RESUMO

Peripheral blood progenitor cells (PBPCs) have become increasingly popular over the last 15 years as the source of hematopoietic stem cells for transplantation. In the early 1990s, PBPCs replaced bone marrow (BM) as the preferred source of autologous stem cells, and recently the same phenomenon is seen in the allogeneic setting. Under steady-state conditions, the concentration of PBPCs (as defined by CFU-GM and/or CD34+ cells) is very low, and techniques were developed to increase markedly this concentration. Such mobilization techniques include daily injections of filgrastim (G-CSF) or a combination of chemotherapy and growth factors. Leukapheresis procedures allow the collection of large numbers of circulating white blood cells (and PBPCs). One or two leukapheresis procedures are often sufficient to obtain the minimum number of CD34+ cells considered necessary for prompt and consistent engraftment (i.e., 2.5-5.0 x 10(6)/kg). As compared to BM, autologous transplants with PBPCs lead to faster hematologic recovery and have few, if any, disadvantages. In the allogeneic arena, PBPCs also result in faster engraftment, but at a somewhat higher cost of chronic graft-versus-host disease (GvHD). This may be a double-edged sword leading to both increased graft-versus-tumor effects and increased morbidity. The rapid advances in the study of hematopoietic, and even earlier, stem cells will continue to shape the future of PBPC transplantation.


Assuntos
Transplante de Células-Tronco Hematopoéticas , Antígenos CD34 , Transplante de Medula Óssea , Filgrastim , Doença Enxerto-Hospedeiro , Fator Estimulador de Colônias de Granulócitos/uso terapêutico , Mobilização de Células-Tronco Hematopoéticas , Transplante de Células-Tronco Hematopoéticas/história , Transplante de Células-Tronco Hematopoéticas/métodos , História do Século XX , Humanos , Proteínas Recombinantes
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