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1.
A DBA/1 B10.D2-specific monoclonal antibody (CY34) is described which defines a new murine B lymphocyte differentiation antigen designated Lyb-8.2. The ontogeny, strain distribution, and cell-surface density of the antigen were studied by radioimmunoassay and by fluorescence-activated cell sorter (FACS) analysis. Lyb-8.2 appears to be expressed on pre-B cells and on all mature B lymphocytes. Lyb-8.2 molecules immunoprecipitated from surface labeled B10.D2 spleen cells migrated in polyacrylamide gels with an apparent mol. wt. of 95000–105000 daltons and were bound by lentil lectin. The expression of Lyb-8.2 is controlled by a locus on chromosome 7 that is closely linked to Gpi-1 and RP-2. Added Lyb-8.2-specific antibody did not measurably impair B lymphocyte function in several in vitro systems studied. 相似文献
2.
B. R. Bondada 《Journal of Plant Growth Regulation》2011,30(2):185-198
The anatomical and micro-morphological alterations as induced by the auxinic herbicide, 2,4-D (2,4-dichlorophenoxy acetic
acid) have not yet been elucidated for a commercially important fruit crop such as grapevine despite its super sensitivity
to 2,4-D. Light and scanning electron microscopy techniques were employed to examine 2,4-D induced internal and external structural
abnormalities in Merlot grapevines (Vitis vinifera L.). Healthy leaves were dorsiventrally flattened with well developed patterns of cellular structure and composition involving
adaxial palisade parenchyma and abaxial spongy mesophyll. Dorsiventral variations in epidermal features involved large epidermal
cells on the adaxial surface, and trichomes and stomata with turgid elliptical guard cells on the abaxial surface. The 2,4-D
injured leaves were small and enated; the veins were fasciated with rugose bands of lamina existing between fasciated veins.
The epidermal cells aggregated instead of being positioned coplanar to the epidermal plane. The adaxial elongated palisade
parenchyma cells were transformed into an ovoid shape with intercellular spaces. An extensive development of replacement tissues
took place on the abaxial surface wherein the stomata became roundish and were either raised or sunken with collapsed and
cracked guard cells that developed abnormal outer stomatal ledges. These abnormalities are expected to severely perturb the
vital functions of photosynthesis and transpiration ultimately leading to vine death attributable, at least in part, to the
injured leaves. 相似文献
3.
The objective of this study was to describe a wide spectrum of surface structural and anatomical details of the Chinese brake
fern (Pteris vittata) using scanning electron microscopy (SEM). SEM revealed that the epidermal cells of the pinnae were elongated with raised
periclinal and sinuous anticlinal walls. The pinnae were hypostomatous with randomly scattered anomocytic stomatal complexes
positioned at the same level as the epidermis. Stomates were large and elliptical (27.4 μm × 10.2 μm). Cross sections from
the central regions of the rachis and the stipe revealed V- and U-shaped vascular bundles, respectively. In each vascular
bundle, the xylem strands were sea-horse shaped (hippocampus). In contrast, the pinnae possessed a triangular vascular bundle
with uniform mesophyll organization comprising of homogenous lobed parenchyma cells. The indumentum consisted of trichomes
and scales, which formed various types of vestiture. Trichomes were borne only on the pinnae and scales on the rachis and
stipe. The roots developed a dense network of long root hairs averaging 244 μm long, and the xylem consisted of tracheids
with scalariform pitting. Sori were submarginal; continuous along both margins of the pinna and were covered with a false
indusium. The sporangia were oblong with a short thick stalk and the annulus was positioned vertically resulting in transverse
dehiscence of the sporangium. The paraphyses were uniseriate, unbranched, septate and found to be intermixed with the sporangia.
The exine of the globose spores was adorned with thick reticulum in which the areoles contained round tubercles. This study
describes surface features in detail, which is essential to studies examining the issue of whether morphological characteristics
are related to arsenic hyperaccumulation inP. vittata. 相似文献
4.
Lavanya Bondada Ramu Rondla Ugo Pradere Peng Liu Chengwei Li Drew Bobeck Tamara McBrayer Philip Tharnish Jerome Courcambeck Philippe Halfon Tony Whitaker Franck Amblard Steven J. Coats Raymond F. Schinazi 《Bioorganic & medicinal chemistry letters》2013,23(23):6325-6330
Herein, we report the synthesis and structure–activity relationship studies of new analogs of boceprevir 1 and telaprevir 2. Introduction of azetidine and spiroazetidines as a P2 substituent that replaced the pyrrolidine moiety of 1 and 2 led to the discovery of a potent hepatitis C protease inhibitor 37c (EC50 = 0.8 μM). 相似文献
5.
Xiaojia Ren Diana Boriero Luksana Chaiswing Subbarao Bondada Daret K. St. Clair D. Allan Butterfield 《生物化学与生物物理学报:疾病的分子基础》2019,1865(6):1088-1097
Increasing numbers of cancer patients survive and live longer than five years after therapy, but very often side effects of cancer treatment arise at same time. One of the side effects, chemotherapy-induced cognitive impairment (CICI), also called “chemobrain” or “chemofog” by patients, brings enormous challenges to cancer survivors following successful chemotherapeutic treatment. Decreased abilities of learning, memory, attention, executive function and processing speed in cancer survivors with CICI, are some of the challenges that greatly impair survivors' quality of life. The molecular mechanisms of CICI involve very complicated processes, which have been the subject of investigation over the past decades. Many mechanistic candidates have been studied including disruption of the blood-brain barrier (BBB), DNA damage, telomere shortening, oxidative stress and associated inflammatory response, gene polymorphism of neural repair, altered neurotransmission, and hormone changes. Oxidative stress is considered as a vital mechanism, since over 50% of FDA-approved anti-cancer drugs can generate reactive oxygen species (ROS) or reactive nitrogen species (RNS), which lead to neuronal death. In this review paper, we discuss these important candidate mechanisms, in particular oxidative stress and the cytokine, TNF-alpha and their potential roles in CICI. 相似文献
6.
Tanya Chotibut Richard W. Davis Jennifer C. Arnold Zachary Frenchek Shawn Gurwara Vimala Bondada James W. Geddes Michael F. Salvatore 《Molecular neurobiology》2014,49(3):1282-1292
Excess glutamatergic neurotransmission may contribute to excitotoxic loss of nigrostriatal neurons in Parkinson's disease (PD). Here, we determined if increasing glutamate uptake could reduce the extent of tyrosine hydroxylase (TH) loss in PD progression. The beta-lactam antibiotic, ceftriaxone, increases the expression of glutamate transporter 1 (GLT-1), a glutamate transporter that plays a major role in glutamate clearance in central nervous system and may attenuate adverse behavioral or neurobiological function in other neurodegenerative disease models. In association with >80 % TH loss, we observed a significant decrease in glutamate uptake in the established 6-hydroxydopamine (6-OHDA) PD model. Ceftriaxone (200 mg/kg, i.p.) increased striatal glutamate uptake with >5 consecutive days of injection in nonlesioned rats and lasted out to 14 days postinjection, a time beyond that required for 6-OHDA to produce >70 % TH loss (~9 days). When ceftriaxone was given at the time of 6-OHDA, TH loss was ~57 % compared to ~85 % in temporally matched vehicle-injected controls and amphetamine-induced rotation was reduced about 2-fold. This attenuation of TH loss was associated with increased glutamate uptake, increased GLT-1 expression, and reduced Serine 19 TH phosphorylation, a calcium-dependent target specific for nigrostriatal neurons. These results reveal that glutamate uptake can be targeted in a PD model, decrease the rate of TH loss in a calcium-dependent manner, and attenuate locomotor behavior associated with 6-OHDA lesion. Given that detection of reliable PD markers will eventually be employed in susceptible populations, our results give credence to the possibility that increasing glutamate uptake may prolong the time period before locomotor impairment occurs. 相似文献
7.
8.
Gururajan M Jennings CD Bondada S 《Journal of immunology (Baltimore, Md. : 1950)》2006,176(10):5715-5719
B lymphomas account for the majority of the lymphoma cases. BCR expression appears to be important for B lymphoma because most oncogenes are translocated to nonrearranged Ig loci and because all of the variants that arise in anti-idiotypic Ab-treated lymphoma patients remain BCR positive. Based on this and the fact that BCR is required for mature B cell survival, we tested the requirement for continued expression of BCR for the growth and survival of B lymphoma cells. Using Igalpha or Igbeta-specific small interfering RNA (siRNA) to inhibit BCR expression, we demonstrate for the first time that constitutive signaling by BCR is critical for survival and proliferation of both murine and human B lymphoma cells. The BCR signals in lymphoma appear to be mediated by Syk, as it is constitutively active in a variety of B lymphoma cells. Blocking Syk activity by selective inhibitors suppresses growth of several murine and human B lymphomas. 相似文献
9.
Field studies were conducted to investigate ontogenic changes in leaf photosynthesis and chloroplast ultrastructure of a single cotton (Gossypium hirsutum L.) leaf subtending the fruit. A 20-d old leaf was the most physiologically active with net photosynthetic rate (PN) of 16.5 mol m-2 s-1 and nitrogen (N) concentration of 168 mmol m-2. These values declined with leaf age and a close relationship existed between them. Concurrent with declines in PN, ultrastructural alterations occurred in the chloroplast: the 20-d old leaf had increased grana number and thylakoids per granum and a few plastoglobuli. Afterwards, the grana number and thylakoids per granum declined with leaf age indicating disintegrated grana and stroma lamellae. Concomitant with disintegrated membrane system was the presence of numerous large plastoglobuli. The PN was closely related to grana number and thylakoids per granum suggesting that the decline in PN with leaf age was associated with ultrastructural changes in the chloroplast. 相似文献
10.
Cotton leaves are more physiologically active than the bractand the capsule wall of the fruiting structures. To elucidatethe disparities in their physiological behaviour, epidermalcell density, stomatal index, stomatal size, trichome densityand type, and epicuticular wax ultrastructure of cotton leaf,bract and capsule wall were delineated using scanning electronmicroscopy (SEM). The epidermal cells of the outer periclinalwalls on both surfaces of the leaf and bract were raised andconvex. Conversely, the capsule wall epidermal cells were polygonalwith flat outer periclinal walls. The stomatal complex in theleaf and bract was paracytic, whereas in the capsule wall thestomatal complex was anomocytic. The adaxial and abaxial stomataof the leaf were coplanar to the epidermal surface, as opposedto the raised adaxial stomata on the bract. On the contrary,the stomata on the capsule wall surface appeared to be slightlysunken. Furthermore, the capsule wall stomata were larger thanthe stomata on either surface of both the leaf and the bract.The stomatal index was greater on the abaxial surfaces of theleaf and the bract (18.4 and 9.4, respectively) than their correspondingadaxial surfaces (14.4 and 4.7, respectively). Leaves had thehighest stomatal index followed by the bract and the capsulewall. The indumentum consisted of glandular and nonglandulartrichomes, the density of which was greater on the abaxial surfacesthan on the adaxial surfaces of the leaf and bract. The capsulewall indumentum lacked nonglandular trichomes. Epicuticularwax occurred in the form of striations. However, the striationpattern varied among the organs. This study clearly illustratesmorphological disparities in the epidermal features of leaf,bract and capsule wall, helping to explain their physiologicaldivergence. Copyright 2000 Annals of Botany Company Gossypium hirsutum, epicuticular wax, raised stomata, scanning electron microscopy, stomatal index, trichomes 相似文献