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161.
Motomi Ito Kuniaki Watanabe Yoko Kita Takayuki Kawahara DJ Crawford Tetsukazu Yahara 《Journal of plant research》2000,113(1):79-89
Eupatorium were examined by sequencing the internal transcribed spacers (ITS) of nuclear ribosomal DNA and restriction site analysis
of chloroplast DNA. Molecular data provided strong evidence that (1) this genus originated in North America, (2) the genus
diverged into three morphological species groups, Eutrochium, Traganthes and Uncasia in North America, and (3) one of the North American Uncasia lineages migrated into temperate Europe and eastern Asia over the Bering land bridge. The estimated divergence times support
a late Miocene to early Pliocene migration from North America to Eurasia via the Bering land bridge. A European species was
sister to all of the eastern Asian species examined. The disjunct distribution pattern of the genus Eupatorium is incongruent with the classical Arcto-Tertiary geoflora concept.
Received 13 September 1999/ Accepted in revised form 4 January 2000 相似文献
162.
We investigated phylogenetic relationships among Otus scops owls from Socotra Island, the Arabian Peninsula and East Africa using molecular, vocalization and biometric data. The Socotra Scops Owl Otus senegalensis socotranus, currently treated as a subspecies of the African Scops Owl Otus senegalensis, is more closely related to the Oriental Scops Owl Otus sunia and to the endemic Seychelles Scops Owl Otus insularis. Considerable mitochondrial genetic distance and significant morphological differentiation from its two closest relatives, as well as its distinctive vocalizations compared with O. insularis, strongly support recognition of Socotra Scops Owl as a full species. Unexpectedly, two taxa from the Arabian Peninsula, Pallid Scops Owl Otus brucei and African Scops Owl Otus senegalensis pamelae, represent very distinct lineages; O. brucei is basal to a clade that includes taxa found in the Indo‐Malayan region and on Indian Ocean islands. In contrast, O. s. pamelae occupies a well‐supported basal position within a clade of continental Afro‐Palaearctic taxa. The uncorrected‐p genetic distance between O. s. pamelae and its closest relatives (other populations of senegalensis from mainland Africa) is c. 4%. As O. s. pamelae is also well differentiated phylogenetically, morphologically and vocally from O. s. senegalensis, we recommend its elevation to species status, as Otus pamelae. Among mainland African O. senegalensis subspecies, Ethiopian populations appear to represent the most divergent lineage, whereas other lineages from Somalia, Kenya and South Africa are poorly differentiated. The large genetic distance between the Ethiopian haplotype and other African haplotypes (3.2%) suggests that the Ethiopian Otus may represent a cryptic taxon, and we recommend that more individuals be sampled to assess the taxonomic status of this population. 相似文献
163.
Antoinette D. Hillian Megan R. McMullen Becky M. Sebastian Sanjoy Rowchowdhury Sangeeta R. Kashyap Philip R. Schauer John P. Kirwan Ariel E. Feldstein Laura E. Nagy 《The Journal of biological chemistry》2013,288(31):22565-22575
Complement activation is implicated in the development of obesity and insulin resistance, and loss of signaling by the anaphylatoxin C3a prevents obesity-induced insulin resistance in mice. Here we have identified C1q in the classical pathway as required for activation of complement in response to high fat diets. After 8 weeks of high fat diet, wild-type mice became obese and developed glucose intolerance. This was associated with increased apoptotic cell death and accumulation of complement activation products (C3b/iC3b/C3c) in liver and adipose tissue. Previous studies have shown that high fat diet-induced apoptosis is dependent on Bid; here we report that Bid-mediated apoptosis was required for complement activation in adipose and liver. Although C1qa deficiency had no effect on high fat diet-induced apoptosis, accumulation of complement activation products and the metabolic complications of high fat diet-induced obesity were dependent on C1q. When wild-type mice were fed a high fat diet for only 3 days, hepatic insulin resistance was associated with the accumulation of C3b/iC3b/C3c in the liver. Mice deficient in C3a receptor were protected against this early high fat diet-induced hepatic insulin resistance, whereas mice deficient in the negative complement regulator CD55/DAF were more sensitive to the high fat diet. C1qa−/− mice were also protected from high fat diet-induced hepatic insulin resistance and complement activation. Evidence of complement activation was also detected in adipose tissue of obese women compared with lean women. Together, these studies reveal an important role for C1q in the classical pathway of complement activation in the development of high fat diet-induced insulin resistance. 相似文献
164.
Quorum-sensing signal synthesis by the Yersinia pestis acyl-homoserine lactone synthase YspI 下载免费PDF全文
Kirwan JP Gould TA Schweizer HP Bearden SW Murphy RC Churchill ME 《Journal of bacteriology》2006,188(2):784-788
The acyl-homoserine lactone molecular species (AHLs) produced by the Yersinia pestis AHL synthase YspI were identified by biochemical and physical/chemical techniques. Bioassays of extracts from culture supernatants of the recombinant YspI and wild-type Yersinia pestis showed similar profiles of AHLs. Analysis by liquid chromatography-mass spectrometry revealed that the predominant AHLs were N-3-oxooctanoyl-L-homoserine lactone and N-3-oxo-hexanoyl-L-homoserine lactone. 相似文献
165.
Jem Babbington Guy M. Kirwan Abdullah Alsuhaibany Hadoram Shirihai Manuel Schweizer 《Zoology in the Middle East.》2019,65(3):201-207
Members of the Eurasian (or Common) Reed Warbler complex, Acrocephalus scirpaceus, are widespread across much of Europe, Africa, the Middle East and Central Asia. With its relatively complex taxonomy, the identity of several local (and sometimes remote) populations remains somewhat unresolved. In Saudi Arabia, populations of reed warblers were first identified in mangroves at Yanbu’ on the Red Sea coast in 1984, with several subsequent records up to 900 km further south toward the Yemen border. We took morphological data from 51 individuals and genetic material from three individuals captured near Jazan in southwest Saudi Arabia. Both genetic and morphometric data confirmed that these birds belong to the taxon A. scirpaceus avicenniae, sometimes referred to as the Mangrove or Red Sea Reed Warbler. 相似文献
166.
S C Bell S Patel M W Hales P H Kirwan J O Drife 《Journal of reproduction and fertility》1985,74(1):261-270
Antisera raised against the soluble antigens of the endometrium of early pregnancy detected two antigenic proteins of alpha 1 and alpha 2 mobility in extracts of this tissue and were termed antigens A and B. Neither antigen was detected in pregnancy sera or extracts of proliferative endometrium, but antigen B was detected in extracts of secretory endometrium and both were present in amniotic fluid and medium from in-vitro incubations of pregnancy endometrium. Fractionation of radiolabelled medium on ion-exchange chromatography demonstrated that antigens A and B co-eluted with the proteins from which EP14 and EP15 were derived and which were the major secretory polypeptides of pregnancy endometrium in vitro. Further biochemical purification revealed that EP14 (Mr 32 000) was derived from a protein of native molecular weight 36 000 which existed in two forms, whereas EP15 (Mr 28 000) was derived from a dimeric glycoprotein of native molecular weight 56 000. Immunochemical studies demonstrated that antigens A and B are identical to these two secretory proteins and have been termed pregnancy-associated endometrial alpha 1- and alpha 2-globulins (alpha 1- and alpha 2-PEG). 相似文献
167.
Several studies have indicated that olfactory responses are impeded by
amiloride. Therefore, it was of interest to see whether, and if so which,
olfactory epithelial cellular compartments have amiloride- sensitive
structures. Using ultrastructural methods that involved rapid freezing,
freeze-substitution and low temperature embedding of olfactory epithelia,
this study shows that, in the rat, this tissue is immunoreactive to
antibodies against amiloride sensitive Na(+)- channels. However, microvilli
of olfactory supporting cells, as opposed to receptor cilia, contained most
of the immunoreactive sites. Apices from which the microvilli sprout and
receptor cell dendritic knobs had much less if any of the
amiloride-antibody binding sites. Using a direct ligand-binding
cytochemical method, this study also confirms earlier ones that showed that
olfactory receptor cell cilia have Na+, K(+)-ATPase. It is proposed that
supporting cell microvilli and the receptor cilia themselves have
mechanisms, different but likely complementary, that participate in
regulating the salt concentration around the receptor cell cilia. In this
way, both structures help to provide the ambient mucous environment for
receptor cells to function properly. This regulation of the salt
concentration of an ambient fluid environment is a function that the
olfactory epithelium shares with cells of transporting epithelia, such as
those of kidney.
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Transgenic Research - 相似文献