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101.
Philip G. Penketh Krishnamurthy Shyam Raymond P. Baumann Rui Zhu Kimiko Ishiguro Alan C. Sartorelli Elena S. Ratner 《Analytical biochemistry》2016
Alkylating agents are a significant class of environmental carcinogens as well as commonly used anticancer therapeutics. Traditional alkylating activity assays have utilized the colorimetric reagent 4-(4-nitrobenzyl)pyridine (4NBP). However, 4NBP based assays have a relatively low sensitivity towards harder, more oxophilic alkylating species and are not well suited for the identification of the trapped alkyl moiety due to adduct instability. Herein we describe a method using water as the trapping agent which permits the trapping of simple alkylating electrophiles with a comparatively wide range of softness/hardness and permits the identification of donated simple alkyl moieties. 相似文献
102.
K. Raghav J. T. French N. T. Ueno X. Lei S. Krishnamurthy J. M. Reuben V. Valero N. K. Ibrahim 《PloS one》2016,11(1)
Introduction
Although well recognized in breast oncology literature, histologic subtypes have not been previously described in inflammatory breast cancer (IBC). The purpose of this study was to describe lobular subtype in IBC and assess the impact of histology on patient outcomes.Methods
We performed a retrospective analysis of 659 IBC patients at MD Anderson Cancer Center between January 1984 and December 2009. Patients with Invasive Lobular, Mixed Invasive Ductal and Lobular, or Invasive Ducal Carcinomas (ILC, MIC, IDC, respectively) comprise the subject of this report. Patient characteristics and survival estimates were compared by using chi-square test and Kaplan-Meier method with log-rank statistic. Cox proportional hazards models were fit to determine association of histology with outcomes after adjustment for other characteristics.Results
A total of 30, 37, and 592 patients were seen to have invasive lobular, mixed, or ductal histology, respectively. Grade 3 tumors were more common in the ductal group (78%) than in the lobular (60%) or mixed (61%) group (P = 0.01). The 3-year overall survival rates were 68%, 64%, and 62% in the lobular, mixed, and ductal groups, respectively (P = 0.68). After adjustment, histology did not have a significant effect on death in the lobular group (HR = 0.70, 95% confidence interval [CI]: 0.26–1.94; P = 0.50) or mixed group (HR = 0.53, 95% CI: 0.25–1.13; P = 0.10) compared with the ductal group.Conclusion
In this cohort of IBC patients, lobular histology was seen in 4.5% cases. Histology does not appear to have a significant effect on survival outcomes in IBC patients, unlike in patients with non-inflammatory breast cancer (n-IBC), indicating the distinct biological behavior of the IBC phenotype. 相似文献103.
K. Krishnamurthy 《Hydrobiologia》1967,29(1-2):226-238
Summary The seasonal variations of marine (collected at the ten fathom line-Station A) and estuarine (collected at the Mouth of the Vellar estuary-Station I) plankton of Porto Novo (India) are described, covering the period 1960–63. The biological, temporal and numerical variations of phytoplankton and zooplankton are described for the two stations. The succession of species was more or less similar at both stations, but certain forms like colonial Radiolaria, Scyphomedusae, Anthozoa, trochophore of Sipunculids, Stomatopod larvae and Protochordate larvae were relatively more confined to Station A, and crustacean larvae other than Stomatopods Actinotrocha larva, fish eggs and larvae were relatively more confined to Station I.The Diatom main peak was about June–July at Station A and about May–July at Station I. The Diatom peak was generally heralded with the appearance of Coscinodiscus. Noticluca usually showed three spurts- mainly two distict ones about May–June and August. The third development was only during certain years and not so intensive. Copepods showed two peaks generally during June–July after few days of the Diatom bloom, and during October–November following the first monsoon rains.The peaks of Diatoms, Peridinians, Noctiluca, Molluscan larvae and Tunicate larvae were more marked at Station A than at Station I. A rich and varied zooplankton was observed about February at Station A. The appearance of salps at Station A seems in a way to be related to salinity, when the salinity values were between 28.89–34.55, the salps appearing more with a fall in salinity. Similarly at Station I, Creseis acicula, Prawn larvae and fish larvae seem to be associated with a sudden fall in temperature and salinity when the monsoon rains start, at Station I.The numerical relationship of plankton at Station A was generally inverse between phyto- and zooplankton and this was generally parallel at Station I.
Sumario La variación estacional del plancton marino (collectado en la ten fathom lineestacción A) y estuarino (Mouth of the Vellar estuary) és descrita para el período 1960–63. Las variaciones biológicas, temporales y numéricas del fitoplancton y del zooplancton son descritas para las dos estacciones. La succesión de especies fué más o menos comparable en las dos estacciones; algunas formas como colonial radiolaria, scyphomedusae, anthozoa, trochophore y sipunculids, stomatopod larvae, y protochordate larvae fuéron confinadas a la estacción A, y otras como crustacean larvae, Actinotrocha larva, peces eggs y larvae confinades a la estacción I.El maximum para las diatomeas ocurrió en Junio–Julio en la estacción A,y Mayo–Junio en la estación I. Las diatomeas están representadas principalmente por el génere Coscinodiscus antes del maximum. El maximum para Noctiluca fue observado en Mayo–Junio y en Agosto. Los copepodes presentaran dos períodos de maximum Junio–Julio despues del maximum de las diatomeas y en Octubre–Noviembre. El maximum de las diatomeas, peridianians, Noctiluca, molluscan larvae y tunicate larvae en la estacción A fué mas distincto que en la estacción en el estuario. El zooplancton se mostró rico y variado en Febrero en la estacción A.La presencia de salpas en la estacción A parace ser relacionada en ciertos aspectos con la diminuición de la salinidad cuando esta fué 28.89–34.55. Por la misma forma la presencia de Creseis acicula, prawn larvae, peces eggs y larvae parace ser relacionada con diminuición de salinidad y temperatura del agua durante Octobre–Noviembre–Deciembre en la estacción I. Las relaciones numéricas del plancton indican que en la estacción A fueran contrarias y en la estacción I paralelas.相似文献
104.
105.
We have determined X-ray crystal structures of four members of an archaeal specific family of proteins of unknown function (UPF0201; Pfam classification: DUF54) to advance our understanding of the genetic repertoire of archaea. Despite low pairwise amino acid sequence identities (10–40%) and the absence of conserved sequence motifs, the three-dimensional structures of these proteins are remarkably similar to one another. Their common polypeptide chain fold, encompassing a five-stranded antiparallel β-sheet and five α-helices, proved to be quite unexpectedly similar to that of the RRM-type RNA-binding domain of the ribosomal L5 protein, which is responsible for binding the 5S- rRNA. Structure-based sequence alignments enabled construction of a phylogenetic tree relating UPF0201 family members to L5 ribosomal proteins and other structurally similar RNA binding proteins, thereby expanding our understanding of the evolutionary purview of the RRM superfamily. Analyses of the surfaces of these newly determined UPF0201 structures suggest that they probably do not function as RNA binding proteins, and that this domain specific family of proteins has acquired a novel function in archaebacteria, which awaits experimental elucidation. 相似文献
106.
Weinbauer GF Aslam H Krishnamurthy H Brinkworth MH Einspanier A Hodges JK 《Biology of reproduction》2001,64(1):120-126
Spermatogenesis is characterized by the succession in time and space of specific germ cell associations (stages). There can be a single stage (e.g., rodents and some macaques) or more than one stage (e.g., chimpanzee and human) per tubular cross section. We analyzed the organization of the seminiferous epithelium and quantified testicular germ cell production and apoptosis in a New World primate, the common marmoset (Callithrix jacchus). Tubule cross sections contained more than one stage, and the human six-stage system could be applied to marmoset spermatogenesis. Stereological (optical disector) analysis (n = 5) revealed high spermatogenic efficiency during meiosis and no loss of spermatids during spermiogenesis. The conversion of type A to type B spermatogonia was several-fold higher than that reported for other primates. Highest apoptotic rates were found for S-phase cells (20%) and 4C cells (15%) by flow cytometric analysis (n = 6 animals); histological analysis confirmed spermatogonial apoptosis. Haploid germ cell apoptosis was <2%. Marmoset spermatogenesis is very efficient and involves substantial spermatogonial proliferation. The prime determinants of germ cell production in primates appear to be proliferation and survival of spermatogonia rather than the efficiency of meiotic divisions. Based on the organizational similarities, common marmosets could provide a new animal model for experimental studies of human spermatogenesis. 相似文献
107.
Krishnamurthy G Ennis DB Itoh A Bothe W Swanson JC Karlsson M Kuhl E Miller DC Ingels NB 《American journal of physiology. Heart and circulatory physiology》2008,295(3):H1141-H1149
We measured leaflet displacements and used inverse finite-element analysis to define, for the first time, the material properties of mitral valve (MV) leaflets in vivo. Sixteen miniature radiopaque markers were sewn to the MV annulus, 16 to the anterior MV leaflet, and 1 on each papillary muscle tip in 17 sheep. Four-dimensional coordinates were obtained from biplane videofluoroscopic marker images (60 frames/s) during three complete cardiac cycles. A finite-element model of the anterior MV leaflet was developed using marker coordinates at the end of isovolumic relaxation (IVR; when the pressure difference across the valve is approximately 0), as the minimum stress reference state. Leaflet displacements were simulated during IVR using measured left ventricular and atrial pressures. The leaflet shear modulus (G(circ-rad)) and elastic moduli in both the commisure-commisure (E(circ)) and radial (E(rad)) directions were obtained using the method of feasible directions to minimize the difference between simulated and measured displacements. Group mean (+/-SD) values (17 animals, 3 heartbeats each, i.e., 51 cardiac cycles) were as follows: G(circ-rad) = 121 +/- 22 N/mm2, E(circ) = 43 +/- 18 N/mm2, and E(rad) = 11 +/- 3 N/mm2 (E(circ) > E(rad), P < 0.01). These values, much greater than those previously reported from in vitro studies, may result from activated neurally controlled contractile tissue within the leaflet that is inactive in excised tissues. This could have important implications, not only to our understanding of mitral valve physiology in the beating heart but for providing additional information to aid the development of more durable tissue-engineered bioprosthetic valves. 相似文献
108.
A method for regenerating pigeonpea [Cajanus cajan (L.) Millsp.] plants has been developed using distal cotyledonary segments of mature seeds as explants. A large number of
shoot buds were induced directly from explants of genotypes T-15-15 and GAUT-82-90 when cultured on six different basal media
fortified with 22.2 μm N6-benzylaminopurine, 2.3 μm kinetin, and 271 μm adenine sulfate. The shoot buds developed into shoots when they were subcultured on the same medium but with one-tenth concentrations
of cytokinins and adenine sulfate. The shoots elongated by subculturing first two to three times on Murashige and Skoog (MS)
basal medium supplemented with 2.22 μm N6-benzylaminopurine and 0.54 μm
α-naphthaleneacetic acid or on half-strength MS medium containing 2.89 μm gibberellic acid, and then once on the same medium without growth regulators. Elongated shoots were rooted with 80–85% efficiency
on MS medium with 4.92 μm indole-3-butyric acid and the plantlets were transferred for hardening. Plants survival in pots was 70–75%. This method may
be useful for improving the crop through genetic manipulations.
Received: 11 August 1997 / Revision received: 12 January 1998 / Accepted: 30 January 1998 相似文献
109.
110.
Callus-mediated shoot regeneration from leaf explants ofPhytophthora resistant pepper (Piper colubrinum Link.) is described. The effect of basal media composition and growth regulators onin vitro response of explants was evaluated. Shoot buds were induced and elongated on half-strength MS medium containing 2.0 mg l–1 BA and 0.5 mg l–1 NAA , as well as 1.0 mg l–1 BA and 0.5 mg l–1 2,4-D. The shoots were rooted in half-strength MS medium with or without IAA or IBA, and then were transferred to soil with 100% survival. 相似文献