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101.
102.
Bhattachary-Chatterjee M Nath Baral R Chatterjee SK Das R Zeytin H Chakraborty M Foon KA 《Cancer immunology, immunotherapy : CII》2000,49(3):133-141
Anti-idiotype (Id) vaccine therapy has been tested and shown to be effective, in several animal models, for triggering the
immune system to induce specific and protective immunity against bacterial, viral and parasitic infections. The administration
of anti-Id antibodies as surrogate tumor-associated antigens (TAA) also represents another potential application of the concept
of the Id network. Limited experience in human trials using anti-Id to stimulate immunity against tumors has shown promising
results. In this “counterpoint” article, we discuss our own findings showing the potential of anti-Id antibody vaccines to
be novel therapeutic approaches to various human cancers and also discuss where anti-Id vaccines may perform better than traditional
multiple-epitope antigen vaccines.
Received: 27 December 1999 / Accepted: 27 January 2000 相似文献
103.
Multicolor FISH analysis of chromosomal breaks, duplications, deletions, and numerical abnormalities in the sperm of healthy men 下载免费PDF全文
Sloter ED Lowe X Moore II DH Nath J Wyrobek AJ 《American journal of human genetics》2000,67(4):862-872
Transmitted de novo structural chromosomal abnormalities, the majority of which are paternally derived, can lead to abnormal reproductive outcomes as well as genetic diseases in offspring. We developed and validated a new multicolor FISH procedure (sperm ACM, which utilizes DNA probes specific for the alpha [1cen], classical, [1q12], and midi [1p36.3] satellites of chromosome 1) which utilizes DNA probes specific for three regions of chromosome 1 to detect human sperm that carry numerical abnormalities plus two categories of structural aberrations: (1) duplications and deletions of 1pter and 1cen, and (2) chromosomal breaks within the 1cen-1q12 region. In healthy men, the average frequencies of sperm with duplications and deletions were (a) 4.5 +/- 0.5 and 4.1 +/- 1.3 per 10(4) involving 1pter and (b) 0.9 +/- 0.4 and 0.8 +/- 0.3 per 10(4) involving 1cen, respectively. The frequency of sperm exhibiting breaks within the 1cen-1q12 region was 14.1 +/- 1.2 per 10(4). Structural aberrations accounted for 71% of the abnormalities detected by sperm ACM, which was significantly higher than numerical abnormalities (P=2x10-8). Our findings also suggest that, for healthy men, (a) sperm carrying postmeiotic chromosomal breaks appear to be more prevalent than those carrying products of premeiotic or meiotic breakage or rearrangements, (b) the high frequency of chromosome breaks measured after "fertilization" by the hamster-egg cytogenetic method already appear to be present and detectable within human sperm by FISH, and (c) there are nonrandom and donor-specific distributions of breakpoint locations within 1q12 in sperm. FISH facilitates the analysis of much larger numbers of sperm than was possible when the hamster-egg method was used. Therefore, FISH-based procedures for simultaneously detecting chromosomal breaks, rearrangements, and numerical abnormalities in sperm may have widespread applications in human genetics, genetic toxicology, and reproductive medicine. 相似文献
104.
A study using transmission electron microscopy (TEM) of the spermatozoa of Rana tigrina and Heteropneustes fossilis in all phases of the annual reproductive cycle revealed that there was a phylogenetic relationship between them. The spermatozoa of H. fossilis appeared horseshoe-shaped, somewhat oval or wedge-shaped at the anterior end and broader at the posterior end. The horseshoe-shaped spermatozoan nucleus was observed during spermiogenesis of R. tigrina but later changed into a finger shape at maturity. The posterior end of the nuclei of mature spermatozoa of R. tigrina was blunt. The extremely dense homogenized nucleus was capped with an acrosomal vesicle in both species suggesting a definite phylogenetic inter-relationship between them. 相似文献
105.
The harvest of non-timber forest products (NTFPs), together with other sources of anthropogenic disturbance, impact plant populations greatly. Despite this, conservation research on NTFPs typically focuses on harvest alone, ignoring possible confounding effects of other anthropogenic and ecological factors. Disentangling anthropogenic disturbances is critical in regions such as India’s Western Ghats, a biodiversity hotspot with high human density. Identifying strategies that permit both use and conservation of resources is essential to preserving biodiversity while meeting local needs. We assessed the effects of NTFP harvesting (fruit harvest from canopy and lopping of branches for fruit) in combination with other common anthropogenic disturbances (cattle grazing, fire frequency and distance from village), in order to identify which stressors have greater effects on recruitment of three tropical dry forest fruit tree species. Specifically, we assessed the structure of 54 populations of Phyllanthus emblica, P. indofischeri and Terminalia chebula spread across the Nilgiri Biosphere Reserve, Western Ghats to ask: (1) How are populations recruiting? and (2) What anthropogenic disturbance and environmental factors, specifically forest type and elevation, are the most important predictors of recruitment status? We combined participatory research with an information-theoretic model-averaging approach to determine which factors most affect population structure and recruitment status. Our models illustrate that for T. chebula, high fire frequency and high fruit harvest intensity decreased the proportion of saplings, while lopping branches or stems to obtain fruit increased it. For Phyllanthus spp, recruitment was significantly lower in plots with more frequent fire. Indices of recruitment of both species were significantly higher for plots in more open-canopy environments of savanna woodlands than in dry forests. Our research illustrates an approach for identifying which factors are most important in limiting recruitment of NTFP populations and other plant species that may be in decline, in order to design effective management strategies. 相似文献
106.
Sigamani Ashokkumar Arunai Nambiraj Sujit Nath Sinha Girigesh Yadav Kothanda Raman Manindra Bhushan Rajesh Thiyagarajan 《Reports of Practical Oncology and Radiotherapy》2015,20(3):170-180
Aim
To measure and compare the head scatter factor for 7 MV unflattened and 6 MV flattened photon beam using a home-made designed mini phantom.Background
The head scatter factor (Sc) is one of the important parameters for MU calculation. There are multiple factors that influence the Sc values, like accelerator head, flattening filter, primary and secondary collimators.Materials and methods
A columnar mini phantom was designed as recommended by AAPM Task Group 74 with high and low atomic number material for measurement of head scatter factors at 10 cm and dmax dose water equivalent thickness.Results
The Sc values measured with high-Z are higher than the low-Z mini phantoms observed for both 6MV-FB and 7MV-UFB photon energies. Sc values of 7MV-UFB photon beams were smaller than those of the 6MV-FB photon beams (0.6–2.2% (Primus), 0.2–1.4% (Artiste) and 0.6–3.7% (Clinac iX (2300CD))) for field sizes ranging from 10 cm × 10 cm to 40 cm × 40 cm. The SSD had no influence on head scatter for both flattened and unflattened beams. The presence of wedge filters influences the Sc values. The collimator exchange effects showed that the opening of the upper jaw increases Sc irrespective of FF and FFF.Conclusions
There were significant differences in Sc values measured for 6MV-FB and unflattened 7MV-UFB photon beams over the range of field sizes from 10 cm × 10 cm to 40 cm × 04 cm. Different results were obtained for measurements performed with low-Z and high-Z mini phantoms. 相似文献107.
Sensory systems have mechanisms to respond to the external environment and adapt to them. Such adaptive responses are effective for a wide dynamic range of sensing and perception of temporal change in stimulus. However, noise generated by the adaptation system itself as well as extrinsic noise in sensory inputs may impose a limit on the ability of adaptation systems. The relation between response and noise is well understood for equilibrium systems in the form of fluctuation response relation. However, the relation for nonequilibrium systems, including adaptive systems, are poorly understood. Here, we systematically explore such a relation between response and fluctuation in adaptation systems. We study the two network motifs, incoherent feedforward loops (iFFL) and negative feedback loops (nFBL), that can achieve perfect adaptation. We find that the response magnitude in adaption systems is limited by its intrinsic noise, implying that higher response would have higher noise component as well. Comparing the relation of response and noise in iFFL and nFBL, we show that whereas iFFL exhibits adaptation over a wider parameter range, nFBL offers higher response to noise ratio than iFFL. We also identify the condition that yields the upper limit of response for both network motifs. These results may explain the reason of why nFBL seems to be more abundant in nature for the implementation of adaption systems. 相似文献
108.
Population dynamics of five different species of grasshopper were analyzed for the first time in Darjeeling (Lebong and Happy Valley) of the eastern Himalayan region of India. The study is based on the relationship between monthly samples collected using sweep nets for three years (March, 2005 to February, 2008) in relation to meteorological parameters (monthly average rainfall, monthly mean maximum and minimum temperatures). The population for each of the five species of grasshopper is plotted against the Aridity Ratio (A.R.). For all species, the population increases at lower A.R. values and then decreases exponentially at higher A.R. values. The exponentially decreasing part of the population is modeled using a simple formula. The monthly population of A. crenulata nymphs and adults in Lebong has also been modeled by iterative equations using A.R. and results compared satisfactorily with the sample data. These works show the possibility of forecasting grasshopper populations using a simple model and thereby easing the regulation process. 相似文献
109.
Vishwas A. Bapat Prabodh K. Trivedi Antara Ghosh Vidhu A. Sane Thumballi R. Ganapathi Pravendra Nath 《Biotechnology advances》2010
Development and ripening in fruit is a unique phase in the life cycle of higher plants which encompasses several stages progressively such as fruit development, its maturation, ripening and finally senescence. During ripening phase, several physiological and biochemical changes take place through differential expression of various genes that are developmentally regulated. Expression and/or suppression of these genes contribute to various changes in the fruit that make it visually attractive and edible. However, in fleshy fruit massive losses accrue during post harvest handling of the fruit which may run into billions of dollars worldwide. This encouraged scientists to look for various ways to save these losses. Genetic engineering appears to be the most promising and cost effective means to prevent these losses. Most fleshy fruit ripen in the presence of ethylene and once ripening has been initiated proceeds uncontrollably. Ethylene evokes several responses during ripening through a signaling cascade and thousands of genes participate which not only sets in ripening but also responsible for its spoilage. Slowing down post ripening process in fleshy fruit has been the major focus of ripening-related research. In this review article, various developments that have taken place in the last decade with respect to identifying and altering the function of ripening-related genes have been described. Role of ethylene and ethylene-responsive genes in ripening of fleshy fruit is also included. Taking clues from the studies in tomato as a model fruit, few case studies are reviewed. 相似文献
110.
Rudra Nath Chatterjee Tarun K. Bhattacharya Meenakshi Dange U. Rajkumar 《Biochemical genetics》2010,48(9-10):727-736
To measure genetic relatedness between populations, for breeding purposes, we analyzed 170 birds from six crossbred populations of three pure lines of White Leghorn chickens, using 14 microsatellite markers. All the microsatellites were polymorphic, with 2–6 alleles. The mean number of alleles per locus was 3.21. The effective number of alleles varied from 1.14 to 3.94. The observed heterozygosity varied from 0.133 to 1.00, with a mean of 0.748. The F IS values were mostly negative, with an average of ?0.345. The mean F ST value was 0.056. The Nm values ranged from 1.91 to 42.17. The highest genetic identity was observed between IWI × IWK and IWK × IWI. The relation between any two groups of crosses was more than 85%. The results suggest that the crossbred populations were very closely related. 相似文献