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11.
Background aimsEnumeration of viable CD34+ cells provides critical information for the bone marrow (BM) transplant physician. The single-platform ISHAGE protocol is the most reliable method currently available to quantitate accurately this important subset of cells. Previous studies have shown that 5 CD34+ cells/µL blood predicts the collection of at least 0.5 × 106 CD34+ cells/kg patient weight. From the apheresis product, infusion of 2.5 × 106 viable CD34+ cells (measured pre-cryopreservation)/kg patient weight will reliably permit engraftment of the hematopoietic system (as measured by the time to 20000 platelets/µL) by day 12–14 post-infusion.MethodsWe compared the CD34+ cell numbers derived from Flow Count-based Stem-Kit?; (Beckman Coulter) and Trucount? tube-based stem cell enumeration (SCE) kit (BD Biosciences) ISHAGE templates on BD FACSCalibur? and BD FACSCanto? cytometers on 12 granulocyte–colony-stimulating factor (G-CSF)-mobilized peripheral blood (MPB) and 10 peripheral blood stem cell (PBSC) samples.ResultsComparison of results showed that there was no statistical difference between samples run with Stem-Kit on the FACSCalibur versus SCE kit-based assays on either the FACSCalibur or FACSCanto. Mean results for the Stem-Kit/Calibur combination were 137, for SCE kit/Calibur 140 and for SCE kit/Canto 137 cells/µL. Pair-wise comparison of data based on rank order showed no statistically significant difference and all correlation coefficients had an R2>0.98.ConclusionsThe two kits generated very similar data on a range of fresh samples regardless of instrument platform. These results confirm and extend the utility of the single-platform ISHAGE protocols with a variety of reagent kits and instrument platforms.  相似文献   
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We have previously identified ring-substituted quinolines as a new structural class of anti-tuberculosis agents. In our ongoing efforts at structural optimization of this class, four series of ring-substituted-2/4-quinolinecarbaldehyde derivatives were synthesized. All twenty-four compounds were synthesized using short and convenient one to two high yielding steps. The newly synthesized compounds were tested in vitro against drug-sensitive Mycobacterium tuberculosis H37Hv strain. Several derivatives were found to be promising inhibitors of M. tuberculosis. For example, derivatives 4a-c (Series 2), 7a-d (Series 3), and 8a-b (Series 4) displayed >90% inhibition at 6.25 microg/mL in the primary assay. The most active compounds, N-(2-fluorophenyl)-N'-quinolin-2-ylmethylene-hydrazine (4a), N-(2-adamantan-1-yl-quinolin-4-ylmethylene)-N'-(4-fluorophenyl)hydrazine (7c), and N-(2-cyclohexyl-quinolin-4-ylmethylene)-N'-(2-fluorophenyl)hydrazine (8a), exhibited 99% inhibition at the lowest tested concentration of 3.125 microg/mL against drug-sensitive M. tuberculosis H37Rv strain. The similarity index based on steric and electrostatic features of the molecules was used, in conjunction with principal component analysis and linear discriminant analysis, successively to classify the molecules based on their activity into two classes. This classification method gives us confidence in predicting the activity class of any new unsynthesized molecule belonging to these series.  相似文献   
13.
R. P. Nayyar 《Genetica》1965,36(1):398-406
The present report is based on the karyotype studies of two species of fishes,Notopterus chitala andN. notopterus, collected from the river Jumna, Delhi, India. Both species possess a diploid number of 48 chromosomes, 12 of which are metacentric. The primary and secondary spermatocytes of one individual ofN. chitala have been found to possess varying numbers of univalent chromosomes. The possible origin and fate of the univalents are discussed.  相似文献   
14.
R. P. Nayyar 《Genetica》1964,35(1):95-104
The present report embodies karyotype studies of seven Indian cyprinids. Of these, the karyotypes of five species possess chromosomes all of which are acrocentric. These areLabeo calbasu (Ham.) 2n=54,Puntius sophore (Ham.),P. conchonius Ham.,P. stigma (Ham.) 2n=50 andChela bacaila (Ham.) 2n=52. The karyotype ofCrossocheilus latius punjabensis Mukerji has 48 chromosomes, 12 of which are metacentric (2n=12m+36r's). InAmblypharyngodon mola (Ham.), 52 chromosomes form the diploid set which include 8 metacentrics. In none of the seven species morphologically distinguishable sex chromosomes were found.Literature on cyprinid karyotypes has been reviewed in order to understand in how far the cytological characters are in agreement with the classification based on morphological studies. The validity ofMatthey's notion of nombre fondamental to establish kinship between cytologically known cyprinid species has also been discussed.  相似文献   
15.
R. P. Nayyar 《Genetica》1966,37(1):78-92
The karyotypes of thirteen species of fishes belonging to nine families, studied in spermatogonial cells and in primary and secondary spermatocytes are reported. All these fishes were collected from the river Jumna near Delhi (India). The diploid number of chromosomes of these species ranges between 86 (Wallago attu) and 40 (Ompak bimaculatus). The karyotypes of seven species are characterized by exclusively possessing acrocentric chromosomes, while the remaining six species have varying numbers of metacentric chromosomes in addition to acrocentric chromosomes. Species belonging to the same family, and even the same genus, have been found to differ in chromosome number and morphology.On the basis of the data available, the author has endeavoured to discuss the relationship between cytologically known fish species and the various complications involved in their classification. The validity of the nombre fondamental hypothesis of Matthey in fish karyotypes has also been discussed.  相似文献   
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If left unpollinated, the flowers ofAerides multiflora (Roxb.) andRhynchostylis retusa (L.) Bl. can remain fresh for 17 and 24 d, respectively. However, they begin to wilt at 2 to 3 days after pollination (DAP) and 3 to 4 DAP, respectively, and become senescent at 5 DAP and 7 DAP, respectively. When measured at two developmental phases — Stage 1, start of wilting and Stage 2, progression to senescence — all the floral organs from pollinated flowers had higher contents of total soluble sugars, reducing sugars, and free amino acids than those from unpollinated flowers. A corresponding increase was noted in the activities of hydrolytic enzymes, i.e., α-amylase, β-amylase, and invertase, and proteolytic enzymes (proteases) in those organs. This indicated that signals related to pollination had up-regulated those activities, leading to a breakdown of complex molecules into simpler ones for mobilization. The amounts of sugars and enzyme activity were relatively greater in the pollinated flowers ofA. multiflora compared withR. retusa, and levels were always higher in the floral lips and perianths. When inhibitors of auxin (0.25 mM TIBA) or ethylene (0.25 mM AgNO2) were applied to the pollinated flowers, their senescence was partially prevented, thus signifying hormonal involvement in governing the pollination-induced biochemical alterations normally found in those organs.  相似文献   
19.
IL-10-differentiated dendritic cells (DC10s) can prevent allergen sensitization and reverse the asthma phenotype in mice with established disease. However, little is known about the time-frames over which this tolerance is effective. We report that at 2 wk after i.p. or transtracheal delivery of 1 × 10(6) OVA-, but not house dust mite- presenting, DC10s to OVA-asthmatic mice, significant diminution of airway hyperresponsiveness (AHR) was first apparent, whereas AHR was abrogated between 3 and 10 wk posttreatment. At 13 wk, AHR returned to pretreatment levels but could again be reversed by DC10 retreatment. The impact of a single DC10 treatment on airway eosinophil and Th2 cytokine responses to recall OVA challenge, and on OVA-specific IgE/IgG1 responses, was substantial at 3 wk posttreatment, but progressively increased thereafter, such that at 8 mo, airway eosinophil and Th2 responses to recall allergen challenge remained ~85-95% suppressed relative to saline-treated asthmatic mice. Four biweekly DC10 treatments, whether transtracheal or i.p., reduced all asthma parameters to near background by 8 wk, whereas s.c. DC10 treatments did not affect AHR but did reduce the airway Th2 responses (i.v. DC10 had no discernible effects). Repeated challenge of the DC10-treated mice with aerosolized OVA (100 μg/ml) did not reverse tolerance, but treatment with the indoleamine-2,3-dioxygenase antagonist 1-methyltryptophan or neutralizing anti-IL-10R from days 12 to 21 after DC10 therapy partially reversed tolerance (Th2 cytokine responses, but not AHR). These findings indicate that DC10-induced Th2 tolerance in asthmatic animals is long lived, but that DC10s employ distinct mechanisms to affect AHR versus Th2 immunoinflammatory parameters.  相似文献   
20.
Low‐carbohydrate diets have been associated with significant reductions in weight and HbA1c in obese, diabetic participants who received high‐intensity lifestyle modification for 6 or 12 months. This investigation sought to determine whether comparable results to those of short‐term, intensive interventions could be achieved over a 24‐month study period using a low‐intensity intervention that approximates what is feasible in outpatient practice. A total of 144 obese, diabetic participants were randomly assigned to a low‐carbohydrate diet (<30 g/day) or to a low fat diet (≤30% of calories from fat with a deficit of 500 kcal/day). Participants were provided weekly group nutrition education sessions for the first month, and monthly sessions thereafter through the end of 24 months. Weight, HbA1c, glucose, and lipids were measured at baseline and 6, 12, and 24 months. Of the 144 enrolled participants, 68 returned for the month 24 assessment visit. Weights were retrieved from electronic medical records for an additional 57 participants (total, 125 participants) at month 24. All participants with a baseline measurement and at least one of the three other measurements were included in the mixed‐model analyses (n = 138). The low‐intensity intervention resulted in modest weight loss in both groups at month 24. At this time, participants in the low‐carbohydrate group lost 1.5 kg, compared to 0.2 kg in the low‐fat group (P = 0.147). Lipids, glycemic indexes, and dietary intake did not differ between groups at month 24 (or at months 6 or 12) (ClinicalTrials.gov number, NCT00108459).  相似文献   
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