Normal and abnormal development of human embryos: First report of the analysis of 1,213 intact embryos

Black foot disease, caused by Cylindrocarpon macrodidymum Halleen, Schroers & Crous, is reported damaging table and wine grapes (Vitis vinifera L.) for the first time in Chile. During the summer of 2006, 2- to 5-year-old grapevines showed reduced vigor, shortened internodes, and drying and dying shoots along with abnormal development of roots with growth parallel to the soil surface, necrotic root crowns, and development of secondary roots. Internal necrosis extended from the bark to the pith in diseased parts of the plants. Other symptoms included black discoloration of the wood, gum inclusions in xylem vessels, black streaks in the vascular tissue, and reduction in root biomass, with sunken, necrotic root lesions. Eighteen Cylindrocarpon isolates were collected from roots, vascular elements, and pith tissue of grapevines cultivars (Flame Seedless, Red Globe, Thompson Seedless, Merlot, Carmenere, and Cabernet Sauvignon) from 12 locations in Chile. The isolates were identified on the basis of morphological features. All isolates produced micro- and macroconidia (one to three septa) and chlamydospores in short and intercalary chains (1,4), and by internal transcribed spacer (ITS1-5,8S-ITS4) rDNA and β -tubulin (BT1, and BT2) partial sequences, identical to those of C. macrodidymum (isolate USS074, GenBank Accession No. AY 997558 and isolate USSO150, GenBank Accession No. AY 997598) (2). Phylogenetic analyses placed these isolates in a clade closely related, but clearly distinct from other clades, to C. destructans and C. liriodendri (2,3). Pathogenicity tests were completed by drench inoculation onto 50 6-month-old rooted cuttings of ‘Red Globe’ with 25 ml of conidia suspension (106 conidia ml-1) obtained from four isolates. Ten control cuttings of ‘Red Globe’ were inoculated with an equal volume of sterile distilled water. The plants were incubated for 4 months in a controlled environment facility at 24°C. All isolates tested were pathogenic. In addition, they caused significant root rot (t-test of disease incidence, P = 0.0048) and no significant level of variation was detected between different isolates. C. macrodidymum was reisolated from the region of brown streaking in all the inoculated cuttings and was not isolated from the water-treated controls. To our knowledge, this is the first report of C. macrodidymum causing black foot disease on grapevine in Chile. References: (1) C. D. Booth. Mycol. Pap. (CMI) 104:1, 1966. (2) F. Halleen et al. Stud. Mycol. 50:431, 2004. (3) F. R. Mantiri et al. Can. J. Bot. 79:334, 2001. (4) E. Petit and W. D. Gubler. Plant Dis. 89:1051, 2005.

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Abnormal Development of Haemaphysalis qinghaiensis (Acari: Ixodidae)

Journal of Insect Science ◽

10.1093/jisesa/iew026 ◽

2016 ◽

Vol 16 (1) ◽

Cited By ~ 1

Author(s):

Qiaoyun Ren ◽

Ze Chen ◽

Jin Luo ◽

Guangyuan Liu ◽

Guiquan Guan ◽

...

Keyword(s):

Morphological Features ◽

Posterior Region ◽

Abnormal Development ◽

First Report ◽

Haemaphysalis Qinghaiensis ◽

Shaped Body ◽

Abnormal Morphology ◽

Laboratory Colony

Abstract A single Haemaphysalis qinghaiensis specimen exhibiting abnormal morphology was collected from a tick laboratory colony. The tick had a heart-shaped body with partial twinning of the posterior region (with two anal orifices and two genital grooves). To the best of our knowledge, this is the first report of teratological changes in H. qinghaiensis. The abnormal morphological features are described herein.

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First Report of Sugarcane Leaf Scald in Gabon Caused by a Highly Virulent and Aggressive Strain of Xanthomonas albilineans

Plant Disease ◽

10.1094/pdis-01-13-0044-pdn ◽

2013 ◽

Vol 97 (7) ◽

pp. 988-988

Author(s):

I. Mensi ◽

J.-C. Girard ◽

I. Pieretti ◽

F. Larbre ◽

P. Roumagnac ◽

...

Keyword(s):

Large Scale ◽

Abnormal Development ◽

Post Inoculation ◽

Water Control ◽

Disease Symptoms ◽

Leaf Scald ◽

First Report ◽

Highly Virulent ◽

Geographical Locations ◽

Xanthomonas Albilineans

During a disease inspection at the sugarcane estate SUCAF near Franceville, Gabon, in March 2011, 0.5 to 1 cm wide chlorotic stripes covered with many small red streaks were observed on sugarcane (Saccharum spp.) leaves of a single plant of cultivar R581. After removal of the leaves covering the base of the stalks, abnormal development of basal side shoots was also observed. Transversal sections of a diseased stalk showed reddening of the vessels near the nodes. Circular, convex, smooth, shiny, translucent, non-mucoid, honey-yellow pigmented bacterial colonies were isolated from stalk pieces and side shoots on XAS selective agar medium (1). The nucleotide sequence of the 16S-23S internal transcribed spacer (ITS) of a representative colony was shown to be 100% identical to the 16S-23S ITS sequence from the genome of Xanthomonas albilineans strain GPE PC73 (GenBank: FP565176.1). This strain from Gabon was named GAB266. Sugarcane stalks of greenhouse grown cultivar CP68-1026 were inoculated with X. albilineans strains XaFL07-1 from Florida, GPE PC73 from Guadeloupe, and GAB266. Five stalks were inoculated by the modified decapitation method (3) with each strain or with a water control. One month post-inoculation (MPI), white pencil lines and severe necrosis were observed on leaves inoculated with strains XaFL07-1 and GPE PC73, and no disease symptoms appeared on non-inoculated leaves that developed 2 to 3 MPI. These results are in agreement with those generally obtained after inoculation of susceptible sugarcane cultivars with X. albilineans strains from various geographical locations under greenhouse conditions (Rott, unpublished results). In contrast, 1 MPI, only discrete white to red pencil lines were observed along with necrosis on leaves inoculated with strain GAB266, and by 2 to 3 MPI, all five inoculated plants were wilted. The pathogen was successfully reisolated by the stalk blot inoculation technique (3) with XAS medium, from all five inoculated stalks and from 98 of 114 internodes. In a second greenhouse experiment, the same three strains of X. albilineans were inoculated as described above into five sugarcane cultivars differing in resistance to leaf scald in Guadeloupe (2) (CP68-1026, highly susceptible; B69566, susceptible; R570, tolerant; B8008, resistant; Co6415, highly resistant). The same symptoms as those described above were again observed on inoculated leaves of the five sugarcane cultivars 1 MPI. Strains XaFL07-1 and GPE PC73 produced occasionally a single pencil line on non-inoculated leaves 2 to 3 MPI, but only strain GAB266 caused leaf scalding and/or plant death 2 to 3 MPI: cultivar CP68-1026 (5 of 5 plants), B69566 (5 of 5 plants), R570 (4 of 5 plants), B8008 (5 of 5 plants), and only non-inoculated leaves of cultivar Co6415 remained symptomless (5 plants). Strain GAB266 from Gabon appeared, therefore, more virulent and aggressive than the two strains of X. albilineans from Florida and Guadeloupe. To our knowledge, this is the first report of leaf scald of sugarcane in Gabon and the first description of an unusual highly virulent and aggressive strain of X. albilineans. A large-scale survey needs to be undertaken to determine the distribution of leaf scald disease and this new pathotype/race of X. albilineans in Gabon and other geographical locations. References: (1) M. J. Davis et al. Plant Dis. 78:78, 1994. (2) P. Rott et al. Phytopathology 87:1202, 1997 (3) P. Rott et al. Mol. Plant-Microbe Interact. 24:594, 2011.

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Reprogramming of DNA methylation is linked to successful human preimplantation development

Histochemistry and Cell Biology ◽

10.1007/s00418-021-02008-6 ◽

2021 ◽

Author(s):

Julia Arand ◽

Renee A. Reijo Pera ◽

Mark Wossidlo

Keyword(s):

Dna Methylation ◽

Epigenetic Reprogramming ◽

Preimplantation Development ◽

Abnormal Development ◽

Human Embryos ◽

Apparent Difference ◽

Human Embryogenesis ◽

Tet Enzymes ◽

Early Human ◽

Human Zygotes

AbstractHuman preimplantation development is characterized by low developmental rates that are poorly understood. Early mammalian embryogenesis is characterized by a major phase of epigenetic reprogramming, which involves global DNA methylation changes and activity of TET enzymes; the importance of DNA methylation reprogramming for successful human preimplantation development has not been investigated. Here, we analyzed early human embryos for dynamic changes in 5-methylcytosine and its oxidized derivatives generated by TET enzymes. We observed that 5-methylcytosine and 5-hydroxymethylcytosine show similar, albeit less pronounced, asymmetry between the parental pronuclei of human zygotes relative to mouse zygotes. Notably, we detected low levels of 5-formylcytosine and 5-carboxylcytosine, with no apparent difference in maternal or paternal pronuclei of human zygotes. Analysis of later human preimplantation stages revealed a mosaic pattern of DNA 5C modifications similar to those of the mouse and other mammals. Strikingly, using noninvasive time-lapse imaging and well-defined cell cycle parameters, we analyzed normally and abnormally developing human four-cell embryos for global reprogramming of DNA methylation and detected lower 5-methylcytosine and 5-hydroxymethylcytosine levels in normal embryos compared to abnormal embryos. In conclusion, our results suggest that DNA methylation reprogramming is conserved in humans, with human-specific dynamics and extent. Furthermore, abnormalities in the four-cell-specific DNA methylome in early human embryogenesis are associated with abnormal development, highlighting an essential role of epigenetic reprogramming for successful human embryogenesis. Further research should identify the underlying genomic regions and cause of abnormal DNA methylation reprogramming in early human embryos.

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A fossil Aspergillus from Eocene Dominican amber

Journal of Paleontology ◽

10.1017/s0022336000058996 ◽

1988 ◽

Vol 62 (01) ◽

pp. 141-143 ◽

Cited By ~ 15

Author(s):

Gerard M. Thomas ◽

George O. Poinar

Keyword(s):

Dominican Republic ◽

Fossil Species ◽

First Report ◽

Dominican Amber ◽

Eocene Amber

A sporulating Aspergillus is described from a piece of Eocene amber originating from the Dominican Republic. The Aspergillus most closely resembles a form of the white spored phase of Aspergillus janus Raper and Thom. This is the first report of a fossil species of Aspergillus.

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