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1.
Zootaxa ; 5415(3): 493-498, 2024 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-38480188

RESUMEN

We describe the new genus and species Stolleagrion foghnielseni n. gen. et sp. from the Fur Formation in northwestern Denmark based on a single fossil wing. This is the first odonatan described from the earliest part of the PETM recovery phase of the early Eocene. A combination of nine wing character states are considered to be diagnostic of the Dysagrionidae Cockrell only together with the cephalozygopteran head; however, the combination of these nine plus the presence of Ax0 is also diagnostic without the head. By this, we assign Stolleagrion foghnielseni to the Dysagrionidae and reassess the position of other odonates previously treated as cf. Dysagrionidae.


Asunto(s)
Odonata , Animales , Fósiles , Alas de Animales
2.
Plant Biol (Stuttg) ; 26(3): 485-491, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38441404

RESUMEN

In plant ecology, the terms growth and development are often used interchangeably. Yet these constitute two distinct processes. Plant architectural traits (e.g. number of successive forks) can estimate development stages. Here, we show the importance of including the effect of development stages to better understand size-related trait scaling relationships (i.e. between height and stem diameter). We focused on one common savanna woody species (Senegalia nigrescens) from the Greater Kruger Area, South Africa. We sampled 406 individuals that experience different exposure to herbivory, from which we collected four traits: plant height, basal stem diameter, number of successive forks (proxy for development stage), and resprouting. We analysed trait relationships (using standardized major axis regression) between height and stem diameter, accounting for the effect of ontogeny, exposure to herbivory, and resprouting. The number of successive forks affects the scaling relationship between height and stem diameter, with the slope and strength of the relationship declining in more developed individuals. Herbivory exposure and resprouting do not affect the overall height-diameter relationship. However, when height and stem diameter were regressed separately against number of successive forks, herbivory exposure and resprouting had an effect. For example, resprouting individuals allocate more biomass to both primary and secondary growth than non-resprouting plants in more disturbed conditions. We stress the need to include traits related to ontogeny so as to disentangle the effect of biomass allocation to primary and secondary growth from that of development in plant functional relationships.


Asunto(s)
Fabaceae , Plantas , Humanos , Madera , Biomasa , Ecología
3.
Zootaxa ; 5278(2): 289-317, 2023 May 05.
Artículo en Inglés | MEDLINE | ID: mdl-37518283

RESUMEN

The earliest Eocene odonate genus Furagrion Petrulevicius et al. from the Danish Fur Formation is revised based on eighteen specimens, two of which apparently have been lost since their publication. The holotype of Phenacolestes jutlandicus Henriksen, type species of Furagrion, is incomplete and lacks the characters currently used to differentiate species, genera and higher taxa in Odonata. We, therefore, propose that the holotype is set aside and a recently discovered nearly complete Fur Formation fossil is designated as neotype. Furagrion possesses all of the nine wing character states currently used along with head shape for diagnosing the Dysagrionidae; however, Furagrion has a characteristically zygopteran head, not the distinctive head shape of the suborder Cephalozygoptera. We, therefore, treat it as a zygopteran unassigned to family. These nine wing character states appear in different combinations not only in various Zygoptera and Cephalozygoptera, but also in the Frenguelliidae, an Eocene family of Argentina that may represent an unnamed suborder. We recognise these taxa as constituting a dysagrionoid grade, in which these character states appear either convergently or as symplesiomorphies. Furagrion morsi Zessin is synonymized with Phenacolestes jutlandicus Henriksen, syn. nov. and Morsagrion Zessin with Furagrion Petrulevicius, Wappler, Wedmann, Rust, and Nel, syn. nov.


Asunto(s)
Odonata , Animales , Fósiles , Alas de Animales
4.
Zootaxa ; 5278(1): 1-38, 2023 May 04.
Artículo en Inglés | MEDLINE | ID: mdl-37518298

RESUMEN

We erect the Cenocimbicinae, a new subfamily of Cimbicidae (Hymenoptera, Symphyta), restricted to the Selandian Menat Formation of France, the oldest occurrence of the family, and the Ypresian Okanagan Highlands of far-western North America. We describe new taxa from the Okanagan Highlands: Allenbycimbex morrisae gen. et sp. nov. and Leptostigma n. gen. with seven new species: L. alaemacula n. sp., L. brevilatum n. sp., L. fasciatum n. sp., L. longiclava n. sp., L. longipallidum n. sp., L. longitenebricum n. sp., and L. proxivena n. sp. We revise the Cimbicidae from the Ypresian Green River Formation and the Priabonian Florissant Formation, both in Colorado, USA. The oldest fossil of a modern cimbicid subfamily appears with a single pachylostictine specimen in the Green River Formation, and all Cimbicidae are in modern subfamilies after the Ypresian (we did not examine one larva known from Priabonian Baltic amber). Pseudocimbex clavatus Rohwer 1908 from the Florissant Formation is not a cimbicid; we treat it as Tenthredinoidea incertae sedis. We transfer Cimbex vetusculus Cockerell to Floricimbex n. gen.

5.
Gene ; 851: 147049, 2023 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-36384171

RESUMEN

A cis-regulatory genetic element which targets gene expression to stem cells, termed stem cell enhancer, serves as a molecular handle for stem cell-specific genetic engineering. Here we show the generation and characterization of a tamoxifen-inducible CreERT2 transgenic (Tg) mouse employing previously identified hematopoietic stem cell (HSC) enhancer for Runx1, eR1 (+24 m). Kinetic analysis of labeled cells after tamoxifen injection and transplantation assays revealed that eR1-driven CreERT2 activity marks dormant adult HSCs which slowly but steadily contribute to unperturbed hematopoiesis. Fetal and child HSCs that are uniformly or intermediately active were also efficiently targeted. Notably, a gene ablation at distinct developmental stages, enabled by this system, resulted in different phenotypes. Similarly, an oncogenic Kras induction at distinct ages caused different spectrums of malignant diseases. These results demonstrate that the eR1-CreERT2 Tg mouse serves as a powerful resource for the analyses of both normal and malignant HSCs at all developmental stages.


Asunto(s)
Células Madre Adultas , Células Madre Hematopoyéticas , Animales , Ratones , Cinética , Feto , Ingeniería Genética , Ratones Transgénicos , Subunidad alfa 2 del Factor de Unión al Sitio Principal/genética
6.
Zootaxa ; 5133(3): 301-345, 2022 May 05.
Artículo en Inglés | MEDLINE | ID: mdl-36101096

RESUMEN

The green lacewings (Neuroptera: Chrysopidae) of the late Eocene Florissant Formation (Colorado, USA) are revised. Thirteen species in six genera of Nothochrysinae are recognized, including four new species: Archaeochrysa cockerelli sp. nov., Cimbrochrysa americana sp. nov., C. major sp. nov., and Lithochrysa meyeri sp. nov. The validity of the genus Dyspetochrysa Adams, 1967 is tenuous; it might be a synonym of Archaeochrysa Adams, 1967. Lithochrysa Carpenter, 1935 and L. ferruginea (Cockerell, 1909) are considered a valid genus and species. A lectotype and paralectotype of Tribochrysa firmata Scudder, 1890 are designated. The genus Cimbrochrysa Schlter, 1982 is recorded from North America for the first time. Eocene chrysopid assemblages are briefly analyzed. The late Eocene Florissant assemblage is less diverse than those of early Eocene North America, and greatly differs from late Eocene European assemblages.


Asunto(s)
Holometabola , Insectos , Animales , Colorado , Fósiles
7.
Zootaxa ; 5105(2): 289-295, 2022 Mar 03.
Artículo en Inglés | MEDLINE | ID: mdl-35391300

RESUMEN

A new fossil horntail wood wasp (Hymenoptera, Symphyta, Siricidae), Eourocerus anguliterreus gen. et sp. nov. from an early Eocene Okanagan Highlands locality at Republic, Washington, USA is described. Its forewing is most like that of the extant and fossil genus Urocerus Geoffroy, 1785. It is the third fossil siricid described from North America. We treat Xeris dorbnikensis Manukyan Smirnova, 2021 and Xeris sp. of Manukyan Smirnova (2021) as Urocerus dorbnikensis (Manukyan Smirnova, 2021), comb. nov. and Urocerus sp., both tentatively belonging to the genus, Urocerus klebsi Brues, 1926 as Xeris klebsi (Brues, 1926) comb. nov., and Afrotremex or Eriotremex sp. of Wedmann (1998) as a species of Eriotremex Benson, 1943. A key to extant and extinct genera of Siricinae by forewing characters is given.


Asunto(s)
Himenópteros , Avispas , Animales , Fósiles , Washingtón
8.
Zootaxa ; 5099(5): 586-592, 2022 Feb 16.
Artículo en Inglés | MEDLINE | ID: mdl-35391395

RESUMEN

We propose Danowhetaksa n. gen. (Odonata: Whetwhetaksidae) with two new species: D. birgitteae n. gen. et sp. and D. rusti n. gen. et sp. from the earliest Ypresian Stolleklint clay of the lst Formation in northwestern Denmark. Whetwhetaksidae has previously been known only from the Ypresian Okanagan Highlands of far-western North America, the new records are, therefore, the first from the Palearctic Region.


Asunto(s)
Odonata , Animales , Fósiles
9.
Zootaxa ; 5099(4): 496-500, 2022 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-35391400

RESUMEN

We describe the darner dragonfly Kishenehna prima n. gen. and sp. (Odonata, Aeshnidae, Gomphaeschninae) based on a well-preserved, nearly complete female hind wing from the Lutetian Coal Creek Member of the Kishenehn Formation, northwestern Montana, USA. Kishenehna is morphologically close to the late Paleocene genus Alloaeschna Wighton Wilson of Alberta, Canada. This is the first dragonfly (Anisoptera) described from the Kishenehn Formation and the first from the Lutetian of the Western Hemisphere.


Asunto(s)
Odonata , Ortópteros , Animales , Femenino , Montana , Alas de Animales
10.
Zootaxa ; 5100(4): 559-572, 2022 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-35391059

RESUMEN

We revise the subfamily Zeuneropterinae (Orthoptera, Ensifera) and treat it as the family Palaeorehniidae Zeuner stat. nov. We restore the late Eocene Palaeorehnia Cockerell from Florissant, Colorado, USA to the taxon and describe two new genera and species in it: Ypopteron nicola n. gen., n. sp. from Quilchena, British Columbia, Canada and Republicopteron douseae n. gen., n. sp. from Republic, Washington, USA. Given current knowledge, Palaeorehniidae appears intermediate between the Stenopelmatoidea and the Hagoidea (s.s.).


Asunto(s)
Ortópteros , Distribución Animal , Animales , Aves , América del Norte
11.
Zootaxa ; 4999(4): 325-334, 2021 Jul 13.
Artículo en Inglés | MEDLINE | ID: mdl-34810481

RESUMEN

Eoteredon lacoi gen. et sp. nov., is described from the early Eocene Green River Formation in Wyoming, the second fossil siricid genus and species described from North America. We propose Eoteredon as sister to the genus Teredon, whose sole species is one of the rarest of extant Siricidae. The majority of siricids today inhabit temperate Northern Hemisphere forests; Teredon cubensis, however, is one of its few species that live in megathermal tropical lowlands. The Eocene forest that Eoteredon inhabited had a mesothermal to megathermal climate. We place Eoteredon in the context of broad Cenozoic climate change.


Asunto(s)
Fósiles , Avispas , Animales , Ríos
12.
Zootaxa ; 5047(1): 97-100, 2021 09 28.
Artículo en Inglés | MEDLINE | ID: mdl-34811004

Asunto(s)
Odonata , Animales
13.
Cell Rep ; 36(7): 109562, 2021 08 17.
Artículo en Inglés | MEDLINE | ID: mdl-34407416

RESUMEN

Hematopoietic ontogeny consists of two broad programs: an initial hematopoietic stem cell (HSC)-independent program followed by HSC-dependent hematopoiesis that sequentially seed the fetal liver and generate blood cells. However, the transition from HSC-independent to HSC-derived hematopoiesis remains poorly characterized. To help resolve this question, we developed Mds1CreERT2 mice, which inducibly express Cre-recombinase in emerging HSCs in the aorta and label long-term adult HSCs, but not HSC-independent yolk-sac-derived primitive or definitive erythromyeloid (EMP) hematopoiesis. Our lineage-tracing studies indicate that HSC-derived erythroid, myeloid, and lymphoid progeny significantly expand in the liver and blood stream between E14.5 and E16.5. Additionally, we find that HSCs contribute the majority of F4/80+ macrophages in adult spleen and marrow, in contrast to their limited contribution to macrophage populations in brain, liver, and lungs. The Mds1CreERT2 mouse model will be useful to deconvolute the complexity of hematopoiesis as it unfolds in the embryo and functions postnatally.


Asunto(s)
Envejecimiento/metabolismo , Alelos , Células Madre Hematopoyéticas/metabolismo , Integrasas/metabolismo , Animales , Linaje de la Célula/efectos de los fármacos , Embrión de Mamíferos/metabolismo , Feto/citología , Hemangioblastos/metabolismo , Hematopoyesis/efectos de los fármacos , Hígado/embriología , Proteína del Locus del Complejo MDS1 y EV11 , Ratones Endogámicos C57BL , Ratones Transgénicos , Tamoxifeno/farmacología
14.
Zootaxa ; 4966(3): 392400, 2021 May 04.
Artículo en Inglés | MEDLINE | ID: mdl-34186607

RESUMEN

We describe Republica weatbrooki, a new genus and species of damselfly (Odonata, Zygoptera, Euphaeidae, Eodichromatinae) from the early Eocene (Ypresian) fossil locality at Republic, Washington, U.S.A. Its single specimen is the sole damselfly known from the Okanagan Highlands series of localities in far-western North America.


Asunto(s)
Odonata/clasificación , Animales , Fósiles , Washingtón
15.
Zootaxa ; 4980(1): 142156, 2021 May 31.
Artículo en Inglés | MEDLINE | ID: mdl-34186986

RESUMEN

The osmylid subfamily Protosmylinae is revised based on our emended diagnosis: Petrushevskia Martynova, 1958 and Mesosmylidus Jepson et al., 2012 are excluded (both considered Osmylidae incertae sedis), and Sogjuta Martynova, 1958 is transferred to it from the Mesosmylininae. The late Eocene genus Protosmylus Krüger, 1913 is considered a junior synonym of Osmylidia Cockerell, 1908 based on a distinct apomorphy (deeply forked MA in the hind wing), syn. nov. Three new species of Osmylidia from the early Eocene of North America are described: O. donnae sp. nov. from Quilchena, O. glastrai sp. nov. from Republic, Washington, USA, and an unnamed species of Osmylidia is reported from Driftwood Canyon Provincial Park, British Columbia (all localities of the Okanagan Highlands series), and O. taliae sp. nov. from the Green River Formation of Colorado, USA.


Asunto(s)
Fósiles , Insectos/clasificación , Animales , América del Norte
16.
Zootaxa ; 4951(1): zootaxa.4951.1.2, 2021 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-33903413

RESUMEN

Four new species of Raphidiidae are described from the early Eocene of western North America: Megaraphidia antiquissima sp. nov. from McAbee, M. ootsa sp. nov. from Driftwood Canyon, M. hopkinsi sp. nov. from the Allenby Formation (all from British Columbia, Canada), M. klondika sp. nov. from Republic (Washington, United States of America). Archiinocellia Handlirsch, 1910, Archiinocellia oligoneura Handlirsch, 1910 from Horsefly River (British Columbia, Canada), and A. protomaculata (Engel, 2011), comb. nov., from the Green River Formation (Colorado, United States of America) are redescribed. Archiinocellia is assigned to Raphidiidae, sit. nov. The apparent absence of sclerotized gonocoxites 9 in the Archiinocellia protomaculata male is probably plesiomorphic at the family level. As some modern snakeflies do not require a cold interval to complete their development and Eocene Inocelliidae and Raphidiidae lived in regions of warm winters (especially A. protomaculata), adaptation to cold winters in many modern snakeflies is a post-Eocene phenomenon. Eocene Raphidiidae of Europe (Priabonian) differ greatly from those of North America (Ypresian and Priabonian). This pattern might reflect dispersal in either direction or ranges established prior to continental separation. Eocene Inocelliidae of Europe (Priabonian), however, are more similar to those of North America (Ypresian and Lutetian).


Asunto(s)
Fósiles , Insectos/clasificación , Animales , Colombia Británica , Masculino , Ríos
18.
Zootaxa ; 4934(1): zootaxa.4934.1.1, 2021 Feb 24.
Artículo en Inglés | MEDLINE | ID: mdl-33756770

RESUMEN

We describe the Cephalozygoptera, a new, extinct suborder of Odonata, composed of the families Dysagrionidae and Sieblosiidae, previously assigned to the Zygoptera, and possibly the Whetwhetaksidae n. fam. The Cephalozygoptera is close to the Zygoptera, but differs most notably by distinctive head morphology. It includes 59 to 64 species in at least 19 genera and one genus-level parataxon. One species is known from the Early Cretaceous (Congqingia rhora Zhang), possibly three from the Paleocene, and the rest from the early Eocene through late Miocene. We describe new taxa from the Ypresian Okanagan Highlands of British Columbia, Canada and Washington, United States of America: 16 new species of Dysagrionidae of the existing genus Dysagrion (D. pruettae); the new genera Okanagrion (O. threadgillae, O. hobani, O. beardi, O. lochmum, O. angustum, O. dorrellae, O. liquetoalatum, O. worleyae, all new species); Okanopteryx (O. jeppesenorum, O. fraseri, O. macabeensis, all new species); Stenodiafanus (S. westersidei, new species); the new genus-level parataxon Dysagrionites (D. delinei new species, D. sp. A, D. sp. B, both new); and one new genus and species of the new family Whetwhetaksidae (Whetwhetaksa millerae).


Asunto(s)
Odonata , Animales , América del Norte
19.
Oral Oncol ; 116: 105195, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-33618103

RESUMEN

INTRODUCTION: Current research is elucidating how the addition of depth of invasion (DOI) to the 8th edition of the American Joint Committee on Cancer (AJCC) TNM staging for oral cavity squamous cell carcinoma influences its prognostic accuracy. However, there is limited research on survival in pT3N0M0 oral tongue SCC (OTSCC) patients when stratifying by DOI. OBJECTIVES: Determine 5-year overall survival (OS), and cancer-specific survival (CSS) for patients with pT3N0M0 oral OTSCC based on shallow DOI (<10 mm) and deep DOI (10-20 mm). METHODS: Retrospective review involving three tertiary care cancer centers in North America. cT3N0M0 OTSCC patients receiving primary surgical treatment from 2004 to 2018 were identified. Inclusion: age > 18 years old and confirmation of pT3N0M0 OTSCC on surgical pathology. Exclusion: patients undergoing palliative treatment or previous head and neck surgery/radiotherapy. Analysis comprised two groups: shallow pT3 (tumor diameter > 4 cm, DOI < 10 mm) and deep pT3 (DOI 10 mm-20 mm). RESULTS: One hundred and four patients with pT3N0M0 OTSCC were included. Mean age was 59.1 years (range: 18-80.74). Age, gender, and Charlson Comorbidity Index were similar between the two groups (p > 0.05). Recurrence, LVI, PNI, and positive margins were more common in deep T3 tumors (P < 0.05). 5-year OS (50% vs 26%, p = 0.006) and CSS (72% vs 24%, p = 0.005) were worse in deep pT3 tumors. Deep pT3 disease was an independent predictor of OS (p = 0.004) and CSS (p = 0.01) on Cox-Regression analysis. CONCLUSION: DOI is an independent predictor of poor survival in pT3N0M0 OTSCC patients. Consideration should be given to escalating adjuvant therapy for deep pT3N0M0 OTSCC patients.


Asunto(s)
Carcinoma de Células Escamosas de Cabeza y Cuello , Neoplasias de la Lengua , Adulto , Humanos , Persona de Mediana Edad , Invasividad Neoplásica , Estudios Retrospectivos , Tasa de Supervivencia , Neoplasias de la Lengua/cirugía
20.
Exp Hematol ; 85: 20-32.e3, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-32437910

RESUMEN

Mds1-Evi1 (also known as Prdm3) and Prdm16 are two highly related zinc finger transcription factors that, within the hematopoietic system, are both expressed primarily in hematopoietic stem cells (HSCs). Our laboratory previously found that constitutive Mds1-Evi1 knockout mice are viable, but their HSCs are unable to withstand myeloablative chemotherapy or effectively transplant irradiated recipient mice. A similar phenotype has been observed for Prdm16, except that the Prdm16 constitutive knockout is lethal. Here, we created a novel double-knockout model of Mds1-Evi1 and Prdm16 in the bone marrow, in which double knockout occurs only in cells that endogenously express Mds1-Evi1 and only upon induction with tamoxifen. We show that combined Mds1-Evi1/Prdm16 deficiency causes bone marrow failure within 15 days, with rapid loss in all progenitor compartments, while the peripheral blood exhibits progressive reductions in peripheral monocytes and granulocytes. We found that surviving hematopoietic stem cells and granulocytic progenitors had elevated apoptosis and cell division, and were unable to form colonies in vitro; adding back wild-type Mds1-Evi1 or Prdm16 to double-knockout bone marrow restores colony formation, and for MDS1-EVI1, this activity depends on a functional PR domain. All of these phenotypic effects were exhibited at milder levels in Mds1-Evi1 and Prdm16 single-knockout controls. Overall, these results illustrate that Mds1-Evi1 and Prdm16 play additive roles in maintaining normal hematopoietic stem cell survival.


Asunto(s)
Apoptosis/fisiología , Proteínas de Unión al ADN/metabolismo , Células Precursoras de Granulocitos/metabolismo , Hematopoyesis/fisiología , Proteína del Locus del Complejo MDS1 y EV11/metabolismo , Modelos Biológicos , Factores de Transcripción/metabolismo , Animales , Línea Celular , Supervivencia Celular/genética , Proteínas de Unión al ADN/genética , Células Precursoras de Granulocitos/citología , Proteína del Locus del Complejo MDS1 y EV11/genética , Ratones , Ratones Noqueados , Factores de Transcripción/genética
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