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Identification of a mechanism underlying heritable subfertility in roosters homozygous for the rose comb allele
The overall objective of this research was to define the cellular basis underlying
heritable subfertility in roosters homozygous for the rose comb allele (R/R). Fertilization
in the hen is preceded by the ascension of motile sperm through the vagina and sperm
sequestration within sperm storage tubules (SST). The objective of the first set of
experiments was to determine if reduced sperm sequestration could account for subfertility.
Sperm sequestration differed between genotypes following intravaginal insemination (p<0.0001). However, sperm sequestration did not differ between genotypes when sperm
were incubated with SST in vitro (p>0.05). Therefore, subfertility was attributed to
reduced sperm transport within the vagina. To test this hypothesis, an assay was developed
to evaluate fowl sperm motility in vitro. Based upon this assay, ejaculates from subfertile
males contained smaller subpopulations of highly motile sperm than the ejaculates from
controls (p<0.001).
The objective of the next set of experiments was to characterize the motility of
individual sperm and to identify a mechanism that could account for the genotypic
difference in sperm cell motility. Computer-assisted sperm motion analysis evaluation
revealed that ejaculates from controls contained 91% motile sperm whereas ejaculates from
subfertile males contained 62% motile sperm (p<0.001). The ATP concentration in sperm
from subfertile males was 63% less than that of sperm from controls (p<0.001). A link
between sperm ATP concentration and immotility was investigated. First, sperm
metabolism was evaluated using motility as an endpoint. The genotypic difference in sperm
motility persisted when ATP synthesis was limited to glycolysis (p<0.001). Consequently,
mitochondrial respiration could not account for the genotypic difference in sperm motility.
In contrast, sperm uptake of [1,2-³H] 2-deoxy-D-glucose did differ between genotypes (p<0.001). The activity of key glycolytic enzymes, creatine kinase, and dynein ATPase did
not differ between genotypes (p>0.05). Therefore reduced sperm motility did not appear
to be due to ATP synthesis, allocation of high energy phosphate bonds along the axoneme,
or ATP consumption (p>0.05). In conclusion, subfertility of roosters homozygous for the
rose comb allele was attributed to decreased spermatozoal glucose transport
Water Buffalo Genome Science Comes of Age
The water buffalo is vital to the lives of small farmers and to the economy of many countries worldwide. Not only are they draught animals, but they are also a source of meat, horns, skin and particularly the rich and precious milk that may be converted to creams, butter, yogurt and many cheeses. Genome analysis of water buffalo has advanced significantly in recent years. This review focuses on currently available genome resources in water buffalo in terms of cytogenetic characterization, whole genome mapping and next generation sequencing. No doubt, these resources indicate that genome science comes of age in the species and will provide knowledge and technologies to help optimize production potential, reproduction efficiency, product quality, nutritional value and resistance to diseases. As water buffalo and domestic cattle, both members of the Bovidae family, are closely related, the vast amount of cattle genetic/genomic resources might serve as shortcuts for the buffalo community to further advance genome science and biotechnologies in the species
Speckle-pattern visibility of light transmitted through a multimode optical fiber
We show that the reduction in visibility of the speckle pattern obtained from laser light that has been passed through a step-index light guide can be found from a knowledge of the model dispersion of the guide, and the bandwidth of the laser beam
Single-cell RNA sequencing of neurofibromas reveals a tumor microenvironment favorable for neural regeneration and immune suppression in a neurofibromatosis type 1 porcine model
Neurofibromatosis Type 1 (NF1) is one of the most common genetically inherited disorders that affects 1 in 3000 children annually. Clinical manifestations vary widely but nearly always include the development of cutaneous, plexiform and diffuse neurofibromas that are managed over many years. Recent single-cell transcriptomics profiling efforts of neurofibromas have begun to reveal cell signaling processes. However, the cell signaling networks in mature, non-cutaneous neurofibromas remain unexplored. Here, we present insights into the cellular composition and signaling within mature neurofibromas, contrasting with normal adjacent tissue, in a porcine model of NF1 using single-cell RNA sequencing (scRNA-seq) analysis and histopathological characterization. These neurofibromas exhibited classic diffuse-type histologic morphology and expected patterns of S100, SOX10, GFAP, and CD34 immunohistochemistry. The porcine mature neurofibromas closely resemble human neurofibromas histologically and contain all known cellular components of their human counterparts. The scRNA-seq confirmed the presence of all expected cell types within these neurofibromas and identified novel populations of fibroblasts and immune cells, which may contribute to the tumor microenvironment by suppressing inflammation, promoting M2 macrophage polarization, increasing fibrosis, and driving the proliferation of Schwann cells. Notably, we identified tumor-associated IDO1+/CD274+ (PD-L1)+ dendritic cells, which represent the first such observation in any NF1 animal model and suggest the role of the upregulation of immune checkpoints in mature neurofibromas. Finally, we observed that cell types in the tumor microenvironment are poised to promote immune evasion, extracellular matrix reconstruction, and nerve regeneration
A detailed Hapmap of the Sitosterolemia locus spanning 69 kb; differences between Caucasians and African-Americans
BACKGROUND: Sitosterolemia is an autosomal recessive disorder that maps to the sitosterolemia locus, STSL, on human chromosome 2p21. Two genes, ABCG5 and ABCG8, comprise the STSL and mutations in either cause sitosterolemia. ABCG5 and ABCG8 are thought to have evolved by gene duplication event and are arranged in a head-to-head configuration. We report here a detailed characterization of the STSL in Caucasian and African-American cohorts. METHODS: Caucasian and African-American DNA samples were genotypes for polymorphisms at the STSL locus and haplotype structures determined for this locus RESULTS: In the Caucasian population, 13 variant single nucleotide polymorphisms (SNPs) were identified and resulting in 24 different haplotypes, compared to 11 SNPs in African-Americans resulting in 40 haplotypes. Three polymorphisms in ABCG8 were unique to the Caucasian population (E238L, INT10-50 and G575R), whereas one variant (A259V) was unique to the African-American population. Allele frequencies of SNPs varied also between these populations. CONCLUSION: We confirmed that despite their close proximity to each other, significantly more variations are present in ABCG8 compared to ABCG5. Pairwise D' values showed wide ranges of variation, indicating some of the SNPs were in strong linkage disequilibrium (LD) and some were not. LD was more prevalent in Caucasians than in African-Americans, as would be expected. These data will be useful in analyzing the proposed role of STSL in processes ranging from responsiveness to cholesterol-lowering drugs to selective sterol absorption
Discovery of a Cosmological, Relativistic Outburst via its Rapidly Fading Optical Emission
We report the discovery by the Palomar Transient Factory (PTF) of the transient source PTF11agg, which is distinguished by three primary characteristics: (1) bright (R_peak = 18.3 mag), rapidly fading (ΔR = 4 mag in Δt = 2 days) optical transient emission; (2) a faint (R = 26.2 ± 0.2 mag), blue (g' – R = 0.17 ± 0.29 mag) quiescent optical counterpart; and (3) an associated year-long, scintillating radio transient. We argue that these observed properties are inconsistent with any known class of Galactic transients (flare stars, X-ray binaries, dwarf novae), and instead suggest a cosmological origin. The detection of incoherent radio emission at such distances implies a large emitting region, from which we infer the presence of relativistic ejecta. The observed properties are all consistent with the population of long-duration gamma-ray bursts (GRBs), marking the first time such an outburst has been discovered in the distant universe independent of a high-energy trigger. We searched for possible high-energy counterparts to PTF11agg, but found no evidence for associated prompt emission. We therefore consider three possible scenarios to account for a GRB-like afterglow without a high-energy counterpart: an "untriggered" GRB (lack of satellite coverage), an "orphan" afterglow (viewing-angle effects), and a "dirty fireball" (suppressed high-energy emission). The observed optical and radio light curves appear inconsistent with even the most basic predictions for off-axis afterglow models. The simplest explanation, then, is that PTF11agg is a normal, on-axis long-duration GRB for which the associated high-energy emission was simply missed. However, we have calculated the likelihood of such a serendipitous discovery by PTF and find that it is quite small (≈2.6%). While not definitive, we nonetheless speculate that PTF11agg may represent a new, more common (>4 times the on-axis GRB rate at 90% confidence) class of relativistic outbursts lacking associated high-energy emission. If so, such sources will be uncovered in large numbers by future wide-field optical and radio transient surveys
The Spitzer survey of interstellar clouds in the Gould Belt. II. The Cepheus Flare observed with IRAC and MIPS
We present Spitzer IRAC (~2 deg^2) and MIPS (~8 deg^2) observations of the
Cepheus Flare which is associated with the Gould Belt, at an approximate
distance of ~300 pc. Around 6500 sources are detected in all four IRAC bands,
of which ~900 have MIPS 24 micron detections. We identify 133 YSO candidates
using color-magnitude diagram techniques, a large number of the YSO candidates
are associated with the NGC 7023 reflection nebula. Cross identifications were
made with the Guide Star Catalog II and the IRAS Faint Source Catalog, and
spectral energy distributions (SED) were constructed. SED modeling was
conducted to estimate the degree of infrared excess. It was found that a large
majority of disks were optically thick accreting disks, suggesting that there
has been little disk evolution in these sources. Nearest-neighbor clustering
analysis identified four small protostellar groups (L1228, L1228N, L1251A, and
L1251B) with 5-15 members each and the larger NGC 7023 association with 32 YSO
members. The star formation efficiency for cores with clusters of protostars
and for those without clusters was found to be ~8% and ~1% respectively. The
cores L1155, L1241, and L1247 are confirmed to be starless down to our
luminosity limit of L_bol=0.06 L_sol.Comment: Submitted to ApJSS. 20 figures, 110 page
Quantifying neutralising antibody responses against SARS-CoV-2 in dried blood spots (DBS) and paired sera
The ongoing SARS-CoV-2 pandemic was initially managed by non-pharmaceutical interventions such as diagnostic testing, isolation of positive cases, physical distancing and lockdowns. The advent of vaccines has provided crucial protection against SARS-CoV-2. Neutralising antibody (nAb) responses are a key correlate of protection, and therefore measuring nAb responses is essential for monitoring vaccine efficacy. Fingerstick dried blood spots (DBS) are ideal for use in large-scale sero-surveillance because they are inexpensive, offer the option of self-collection and can be transported and stored at ambient temperatures. Such advantages also make DBS appealing to use in resource-limited settings and in potential future pandemics. In this study, nAb responses in sera, venous blood and fingerstick blood stored on filter paper were measured. Samples were collected from SARS-CoV-2 acutely infected individuals, SARS-CoV-2 convalescent individuals and SARS-CoV-2 vaccinated individuals. Good agreement was observed between the nAb responses measured in eluted DBS and paired sera. Stability of nAb responses was also observed in sera stored on filter paper at room temperature for 28 days. Overall, this study provides support for the use of filter paper as a viable sample collection method to study nAb responses.</p
Global wealth disparities drive adherence to COVID-safe pathways in head and neck cancer surgery
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