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41.
42.
Robertsonian translocations, also called centric fusions, represent the most frequent chromosome anomalies in cattle, and rob(1;29) is the most widespread. However, centric fusions involving other chromosomes have been discovered in different cattle breeds. Here we report the appearance of a new case of rob(14;17) in an Italian cattle breed more than ten years after the first and only case had been observed, and we demonstrate the independent origin of this anomaly from the previous case. 相似文献
43.
Cassata R Iannuzzi A Parma P De Lorenzi L Peretti V Perucatti A Iannuzzi L Di Meo GP 《Cytogenetic and genome research》2008,120(1-2):140-143
The aim of this study was to estimate prognostic factors in a Dalmatian dog with bilateral cryptorchidism and hypospadias. Cytogenetic and molecular analyses revealed a normal karyotype (2n = 78,XY) and the presence of SRY, INSL3 and RXFP2 genes with a normal DNA sequence for SRY and RXFP2, while the INSL3 sequence differed slightly from the normal one due to a heterozygous nucleotide change involving amino acid 22 of the INSL3 dog precursor protein. Levels of plasmatic testosterone were only 0.01 ng/ml, while FSH and LH serum levels were not detectable. After the human chorionic gonadotropin (hCG) test, the serum testosterone level was 0.01 ng/ml. Therefore, the phenotypic aetiology of this subject can not be well-defined because cryptorchidism and hypospadias were frequent clinical features with high genetic heterogeneity. 相似文献
44.
Ana Luiza Fonseca Fortes Furtado Maria do Carmo Calijuri Adriana Sturion Lorenzi Ricardo Yukio Honda Diego Bonaldo Genuário Marli Fátima Fiore 《Hydrobiologia》2009,627(1):195-209
The cyanobacterial population in the Cajati waste stabilization pond system (WSP) from São Paulo State, Brazil was assessed by cell isolation and direct microscope counting techniques. Ten strains, belonging to five genera (Synechococcus, Merismopedia, Leptolyngbya, Limnothrix, and Nostoc), were isolated and identified by morphological and molecular analyses. Morphological identification of the isolated strains was congruent with their phylogenetic analyses based on 16S rDNA gene sequences. Six cyanobacterial genera (Synechocystis, Aphanocapsa, Merismopedia, Lyngbya, Phormidium, and Pseudanabaena) were identified by direct microscope inspection. Both techniques were complementary, since, of the six genera identified by direct microscopic inspection, only Merismopedia was isolated, and the four other isolated genera were not detected by direct inspection. Direct microscope counting of preserved cells showed that cyanobacteria were the dominant members (>90%) of the phytoplankton community during both periods evaluated (summer and autumn). ELISA tests specific for hepatotoxic microcystins gave positive results for six strains (Synechococcus CENA108, Merismopedia CENA106, Leptolyngbya CENA103, Leptolyngbya CENA112, Limnothrix CENA109, and Limnothrix CENA110), and for wastewater samples collected from raw influent (3.70 μg microcystins/l) and treated effluent (3.74 μg microcystins/l) in summer. Our findings indicate that toxic cyanobacteria in WSP systems are of concern, since the treated effluent containing cyanotoxins will be discharged into rivers, irrigation channels, estuaries, or reservoirs, and can affect human and animal health. 相似文献
45.
46.
Tram Huynh Zhong Chen Suhong Pang Jieping Geng Tiziano Bandiera Simona Bindi Paola Vianello Fulvia Roletto Sandrine Thieffine Arturo Galvani Wayne Vaccaro Michael A. Poss George L. Trainor Matthew V. Lorenzi Marco Gottardis Lata Jayaraman Ashok V. Purandare 《Bioorganic & medicinal chemistry letters》2009,19(11):2924-2927
Design, synthesis, and SAR development led to the identification of the potent, novel, and selective pyrazole based inhibitor (7f) of Coactivator Associated Arginine Methyltransferase (CARM1). 相似文献
47.
An Integrated Approach for Experimental Target Identification of Hypoxia-induced miR-210 总被引:1,自引:0,他引:1
48.
S R Chan C G Rickert W Vermi K C F Sheehan C Arthur J A Allen J M White J Archambault S Lonardi T M McDevitt D Bhattacharya M V Lorenzi D C Allred R D Schreiber 《Cell death and differentiation》2014,21(2):234-246
We previously reported that STAT1 expression is frequently abrogated in human estrogen receptor-α-positive (ERα+) breast cancers and mice lacking STAT1 spontaneously develop ERα+ mammary tumors. However, the precise mechanism by which STAT1 suppresses mammary gland tumorigenesis has not been fully elucidated. Here we show that STAT1-deficient mammary epithelial cells (MECs) display persistent prolactin receptor (PrlR) signaling, resulting in activation of JAK2, STAT3 and STAT5A/5B, expansion of CD61+ luminal progenitor cells and development of ERα+ mammary tumors. A failure to upregulate SOCS1, a STAT1-induced inhibitor of JAK2, leads to unopposed oncogenic PrlR signaling in STAT1−/− MECs. Prophylactic use of a pharmacological JAK2 inhibitor restrains the proportion of luminal progenitors and prevents disease induction. Systemic inhibition of activated JAK2 induces tumor cell death and produces therapeutic regression of pre-existing endocrine-sensitive and refractory mammary tumors. Thus, STAT1 suppresses tumor formation in mammary glands by preventing the natural developmental function of a growth factor signaling pathway from becoming pro-oncogenic. In addition, targeted inhibition of JAK2 may have significant therapeutic potential in controlling ERα+ breast cancer in humans. 相似文献
49.
Partner fidelity and egg reciprocation in the simultaneously hermaphroditic polychaete worm Ophryotrocha diadema 总被引:1,自引:0,他引:1
The mating system of the simultaneously hermaphroditic polychaeteworm Ophryotrocha diadema consists of a regular egg exchangebetween partners of a pair. Such reciprocal egg exchange hasbeen considered a form of cooperation, where one partner cooperatesby offering its eggs to be fertilized and expects to receivepartner's eggs to fertilize. Frequency of cases in which hermaphroditescheated (i.e., failed to give up eggs at their turn) and responsesto cheating were estimated by analyzing the behavior of 38
triplets of ovigerous hermaphrodites over a 2-week period. Thepartner did not reciprocate 8% of egg layings. The cheatedpartner did not detect most cases of cheating (16 out of 25).Such a low frequency of cheating can explain why no retaliationmechanism evolved in this species. Sixty-eight percent of the
individuals from the original pairs deserted even if their partnersnever cheated them; therefore, cheating cannot be consideredthe cause of desertion. Rather, desertion appeared to be aconsequence of availability of a new partner whose oocyteswere riper than those of the old partner. It occurred becausethe opportunity arose for an immediate reward, indicating thatO. diadema egg exchange differs from that originally describedin some serranid fish as egg trading. The relationship betweencosts of desertion and population size is discussed. 相似文献
50.
Lorenzi M 《The Western journal of medicine》1985,142(5):679-680