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1.
Om Parkash M. K. Beuria B. K. Girdhar K. Katoch U. Sengupta 《Journal of biosciences》1997,22(1):111-116
Skin scrapings obtained from the lesions of leprosy patients of all types showed 96 % positivity to the serum antibody competition
test using monoclonal antibody (ML04)to 35 kDa antigen of
Mycobacterium leprae. Further, in vitro culture of full thickness skin biopsies from lepromatous patients were noted to release IgG antibodies
toM. leprae with a peak antibody response at 48 h. The significance of this local antibody response toM. leprae in skin has been discussed for its possible use in diagnosing early leprosy. 相似文献
2.
S. Mohan Jain 《Journal of biosciences》1997,22(5):585-592
Begonia
x
elatior
plantlets which regenerated from leaf disk callus showed variations in plant morphology, number of flowers per plant, and
flower size. Variations in flowering period, number of flowers per plant, and flower morphology were observed in
Saintpaulia ionantha
L. plants directly regenerated from leaf disk explants. The cytokinins, benzylaminopurine and zeatin, tested in the culture
medium did not affect the basic plant characteristics including flower colour which remained stable in both species. Micropropagation
of selected somaclones having the desirable trait of high number of flowers per plant was stable in the MV2 and MV3 generations. 相似文献
3.
S. A. Ranade Anil Kumar Mamta Goswami Nuzhat Farooqui P. V. Sane 《Journal of biosciences》1997,22(4):457-464
Amaranths are an important group of plants and include grain, vegetable and ornamental types. Despite the economic importance
of the amaranths, there is very little information available about the extent and nature of genetic diversity present in the
genus
Amaranthus
at molecular level. We now report the randomly amplified polymorphic DNA (RAPD) profiles of different species of
Amaranthus
as well as different accessions of the species. These RAPD analyses have been carried out using 65 arbitrary sequence decamer
primers. From the RAPD data, an UPGMA dendrogram illustrating the inter-as well as intra-species relationships has been computed.
The putative hybrid origin of A.dubious
from
A. hybridus
and
A. spinosus
is also ruled out by the RAPD data. The trends of species relationships amongst the amaranths determined by RAPDs is consistent
with their cytogenetic and evolutionary relationships that have already been determined.
NBRI Communication No:464 (N.S.). 相似文献
4.
Employing the superimposition technique of electron-microscopic immunocytochemistry ultrastructural heterogeneity of the mammotropes
in the pituitary gland of the European ferret,Mustela putorius furo,was studied. On the basis of the size of their secretory granules, the mammotropes were classified into three subtypes, type-I,
type-II and type-Ill, which may correspond to different developmental or physiological states of a single cell type. Simultaneous
study of mammotropes and somatotropes in several pairs of serial semithin sections demonstrated the occasional occurrence
of bihormonal somatomammotropes /mammosomatotropes which may represent a transitional stage of the progenitor stem-somatotrope
during its differentiation into mammotrope; alternatively it may be a functional intermediate during the cross-transformation
of somatotrope into mammotrope or
vice versa. 相似文献
5.
Extracellular signals are transduced across the cell by the cell surface receptors, with the aid of G-proteins, which act
at a critical point of signal transduction and cellular regulation. Structurally, G-proteins are heterotrimeric consisting
α, β and γ subunits but in functionally active state they dissociate into α subunit coupled to GTP and as βγ dimer. G-proteins
can be broadly divided into two classes based on their sensitivity to pertussis toxin and cholera toxin. Existence of various
forms of each of the subunit allows molecular diversity in the subunit species of G-proteins. These subunits interact with
a wide range of receptors and effectors, facilitated by post translational modification of their subunits. Different types
of G-proteins mediate several signalling events in different parts of the body. This review summarizes the features of (i)
structural and functional heterogenity among different subunits of G-proteins, (ii) interaction of G-proteins and their subunits
with effectors with specific cases of G-protein mediated signalling in olfaction, phototransduction in the retina,
ras andras
related transduction and (iii) disease conditions associated with malfunctioning of G-proteins. 相似文献
6.
Determination and diagnostic value of CA9 mRNA in peripheral blood of patients with oral leukoplakia
Manuel Torres López Cintia Chamorro Petronacci Francisco Barros Angueira Pilar Gándara Vila Alejandro Lorenzo Pouso 《Journal of enzyme inhibition and medicinal chemistry》2018,33(1):951-955
Background: Oral leukoplakia is one of the most common oral premalignant disorder. The classical evaluation through tissue biopsy is not always valid to evaluate the risk of malignization.Material and methods: RT-qPCR was performed on 47 blood samples (21 patients with leukoplakia, 2 with oral squamous cell carcinoma (OSCC), and 24 healthy patients) and on 11 tissue samples (3 leukoplakia, 4 OSCC, and 4 samples of healthy tissue).Results: There are significant differences in expression between the different groups (F?=?4.057, p?=?.006). The Duncan post hoc test shows that the only group that differentiates is the tumour tissue. Using Wilcoxon test, different covariables of patients with leukoplakia were analysed with respect to the group of healthy patients and no significant differences were observed.Conclusions: The diagnostic route through liquid biopsy has not been conclusive in this study, but there are significant differences in the levels analysed in the different tissue samples. 相似文献
7.
Two yolk proteins (YP1 and YP2) from the ovaries of Indian major carp, Labeo rohita were isolated by gel filtration and partially
characterized by the use of hydroxyapatite ultrogel column in conjunction with native PAGE. On native PAGE YP1 gave a single
protein band, whereas YP2 of gel filtration revealed the contamination of YP1, which was removed by adsorption chromatography
on hydroxyapatite ultrogel and then the YP2 was the purified one as judged by electrophoresis. Both YP1 and YP2 also stained
for lipid and contained alkalilabile phosphorus. Therefore, both yolk proteins were lipophosphoprotein. The molecular weights
of YP1 and YP2 were 620 kDa and 225 kDa respectively as determined by gel filtration on Sepharose 4B. When YP1 and YP2 were
compared in relation to some physicochemical characteristics with yolk proteins of other oviparous vertebrates including fish,
they were lipovitellin like.
Antiserum to YP2 crossreacted with YP2 and vitellogenin suggesting that YP2 was the cleaved product of vitellogenin. Anti-YP2
antiserum was not crossreacted with native YP1, whereas reduced and/or denatured YP1 was crossreacted indicating the presence
of antigenic determinants in the inner core region of YP1 polypeptide. 相似文献
8.
Amitabh Joshi Wendy A. Oshiro Jason Shiotsugu Laurence D. Mueller 《Journal of biosciences》1997,22(3):325-338
Oviposition preference for ureasupplemented food was assayed by simultaneous choice trials on five pairs of closely related
laboratory populations of
Drosophila melanogaster.Each pair of populations had been derived from a separate ancestral population about 85 generations prior to this study. One
population in each pair had been subjected to selection for larval tolerance to the toxic effects of urea; the other population
served as a control. Considerable variation in oviposition preference was seen both within and among populations, with four
of the ten populations showing a significant mean preference for ureasupplemented food. The degree of specificity shown by
individual females was surprisingly high, leading to a bimodal distribution of oviposition preference in some populations.
Overall, selection for larval tolerance to urea did not significantly affect oviposition preference. However, the data indicated
that pairwise comparisons between randomly selected populations from the two larval selection regimes would lead to a range
of possible outcomes, suggesting, in several cases, that selection for larval urea tolerance had led to significant differentiation
of adult oviposition preference for urea in one or the other direction. The results, therefore, highlight the importance of
population level replication and caution against the practice, common in ecological studies, of assaying oviposition preference
in two populations that utilize different hosts in nature, and then drawing broad evolutionary inferences from the results. 相似文献
9.
The ultradian rhythm of the lateral leaflets ofDesmodium motorium}(Houtt.) Merril. was recorded with a picture analysis method using a video camera and a computer. The periods are in the minute
range and depend strongly on temperature.
The phosphatidyl inositol signal chain might be involved in the ultradian rhythm of the lateral leaflet movement of
Desmodium motorium:Myoinositol shortens the period length and reduces the known period lengthening effect of lithium ions. Neomycin, which inhibits
the hydrolysis of phosphatidylinositol-4,5 -biphosphate to inositol-4-phosphate and diacylglycerin, lengthens the period of
the rhythm at low concentrations (0.2 mM). Higher concentrations shorten the period, perhaps by activating G protein. Mastoparan,
which activates G protein, shortens period likewise. The G protein agonists fluorid ion and ethanol are toxic for the lateral
leaflets and could therefore not be used to test the involvement of G protein.
The intracellular Ca
2+
antagonist 3,4,5-trinietlioxybeiizoic acid 8-(diethylamino)octylester lengthens the period of the rhythm. This indicates,
that release of Cas
2+
from intracellular stores is important for the lateral leaflet movement rhythm. 相似文献
10.
Amino acid sequences of proteinaceous proteinase inhibitors have been extensively analysed for deriving information regarding
the molecular evolution and functional relationship of these proteins. These sequences have been grouped into several well
defined families. It was found that the phylogeny constructed with the sequences corresponding to the exposed loop responsible
for inhibition has several branches that resemble those obtained from comparisons using the entire sequence. The major branches
of the unrooted tree corresponded to the families to which the inhibitors belonged. Further branching is related to the enzyme
specificity of the inhibitor. Examination of the active site loop sequences of trypsin inhibitors revealed that here are strong
preferences for specific amino acids at different positions of the loop. These preferences are inhibitor class specific. Inhibitors
active against more than one enzyme occur within a class and confirm to class specific sequence in their loops. Hence, only
a few positions in the loop seem to determine the specificity. The ability to inhibit the same enzyme by inhibitors that belong
to different classes appears to be a result of convergent evolution. 相似文献
11.
Plant regeneration from mesophyll protoplasts of pepper,Capsicum annuum
L. cv. California Wonder has been demonstrated via shoot organogenesis. Protoplasts isolated from fully expanded leaves of
3-week-old axenic shoots when cultured in TM medium supplemented with 1 mg l
−1
NAA, 1 mg l
−1
2,4-D, 0 5 mg l
−1
BAP (CM 1) resulted in divisions with a frequency ranging from 20–25 %. Antioxidant ascorbic acid and polyvinylpyrrolidone
(PVP) in the medium and incubation in the dark helped overcome browning of protoplasts. Microcalli and macrocalli were formed
in TM medium containing 2 mg l
−1
NAA and 0.5 mg l
−1
BAP (CM II) and MS gelled medium containing 2 mg 1
−1
NAA and 0 5 mg 1
−1
BAP (CM III), respectively. Regeneration of plantlets was possible via caulogenesis. Microshoots, 2–5 percallus appeared on
MS gelled medium enriched with 0.5 mg l
−1
IAA, 2mg l
−1
GA and l0mg l
−1
BAP (CM IVc). Rooting of microshoots was obtained on half strength gelled medium containing 1 mg l
−1
NAA and 0.5mg l
−1
BAP. Protoplasts isolated from cotyledons failed to divide and degenerated eventually. 相似文献
12.
Streptomyces fradiae
produces several extracellular proteases and many of these are inducible. An 8.8 kb DNA fragment of
Streptomyces fradiae
cloned on pIJ699 caused increased protease activity in
Streptomyces lividans.Clones carrying this recombinant plasmid showed a significant delay in sporulation. A protein of 18 kDa was purified from
the extracellular proteins secreted by the host carrying the recombinant plasmid. Further characterization showed that this
protease is a metalloprotease. 相似文献
13.
Tony M. Johnson A. S. Rishi Pritilata Nayak Soumitra K. Sen 《Journal of biosciences》1996,21(5):673-685
Damage caused to rice production by coleopteran insects like rice weevil (Sitophilus oryzae), a stored grain insect pest and rice hispa (Dicladispa armigera), a pest of the growing plant is quite high. In order to combat the damage, generation of insect resistant transgenic rice
plant was considered desirable. CryIIIA endotoxin ofBacillus thuringiensis var.tenebrionis, a 65 kDa protein toxic to coleopteran insects, figured as the candidate gene product. Thus, the cryIIIA gene was isolated
from a local isolate ofBacillus thuringiensis var.tenebrionis. The gene was tailored at the N-terminal end to its minimal size by using a synthetic ATG codon which replaced the first
codon next to ATG of threonine to proline. This modification did not affect the functional property of the gene product. A
chimeric construct of the modifiedcryIIIA gene was developed containing CaMV35S promoter andnos terminator for plant expression. The expressibility of thecryIIIA gene inindica rice was judged through test for transient expression in indica rice protoplasts. 相似文献
14.
The intranasal route is one of the main routes of Mycobacterium leprae infection and there is paucity of information regarding
the mode of spread of the pattern. The adherence of
M.leprae to the nasal mucosa, its trapping within the sinuses of the head, and its fate after entry into the host was studied
using mouse model. A comparison of the adherence profile of
M. leprae
and
Mycobacterium tuberculosis
showed that while larger numbers of
M. tuberculosis
were demonstrated within lungs, greater numbers of
M.leprae were present within the sinuses of the head. Adherence of
M.leprae to the nasal mucosa was dependent on surface integrity since opsonization and heat killing resulted in decreased numbers
of
M.leprae in the nasal sinuses and a greater amount entering the lungs. The adherence appeared to the independent of the viability
of the bacilli, as similar numbers of formalin-fixed, rifampicin-treated and viable
M.leprae entered the lungs in the initial stages. However the numbers of rifampicin-treated
M. leprae
in the nasal sinuses were 12-fold lower than the numbers of viable
M.leprae. These results indicated that both viability and surface integrity were important in the entry of
M.leprae and it’s consequent dissemination. 相似文献
15.
Subramony Mahadevan 《Journal of biosciences》1997,22(4):505-513
The product of the
bglG
gene of Escherichia
coli
was among the first bacterial antiterminators to be identified and characterized. Since the elucidation ten years ago of its
role in the regulation of the
bgl
operon
of E. coli,a large number of homologies have been discovered in both Gram-positive and Gram-negative bacteria. Often the homologues of
BglG in other organisms are also involved in regulating β-glucoside utilization. Surprisingly, in many cases, they mediate
antitermination to regulate a variety of other catabolic functions. Because of the high degree of conservation of the
cis-acting regulatory elements, antiterminators from one organism can function in another. Generally the antiterminator protein
itself is negatively regulated by phosphorylation by a component of the phosphotransferase system. This family of proteins
thus represents a highly evolved regulatory system that is conserved across evolutionarily distant genuses. 相似文献
16.
Gastrimargus africanus orientalis,an acridid grasshopper has revealed the existence of karyotypic mosaicism in the male germ line cells of a few individuals
with 2
n
= 23, 19, 21, 25 and 27 chromosomes. Details of this chromosomal instability are presented in this paper.
We dedicate this paper to our teacher Prof. L Siddaveere Gowda on the eve of his 60th birthday. 相似文献
17.
Changes in ovarian follicular kinetics were studied in relation to aging in the Indian skipper frog
Rana cyanophlyctis.Age was determined by skeletochronology, by counting the number of growth rings and lines of arrest of growth from the cross
sections of 4th phalange of 4th toe. For follicular kinetics study oocytes were counted under binocular using 10% of Bouin’s
fixed ovary and they were classified into first growth phase, medium-sized second growth phase, large-sized second growth
phase and atretic follicles.
Analysis of phalangeal cross sections indicated that frogs ranging 14–54 g in body weight and 4.9–8.9 cm in body size showed
1–7 year rings. Frogs that weighed 14–16 g showed 1 year ring, and contained immature ovaries; those with 18 g body weight
had one to two year rings, in which second growth phase oocytes appeared for the first time in the primiparous ovary. Frogs
with 20–54 g body weight showed 2–5 year rings in which ovary contained 5–24% of second growth phase oocytes. Further, body
weight, body size, ovarian weight, number and size of second growth phase oocytes and total number of oocytes showed a significant
(P < 0.05) positive correlation, while, the number of first growth phase and atretic follicles showed a poor correlation with
age.
The results suggest that in nature, the age of
Rana cyanophlyctis
ranges between 1–7 years. Phalangeal growth rings are formed annually. Females attain sexual maturity in 2nd year. Frogs with
2–5 years of age may constitute breeding females. Body weight, body size, ovarian mass, number of second growth phase and
total oocytes, and egg size increase with age up to 5 years. 相似文献
18.
Krushnamegh J. Kunte 《Journal of biosciences》1997,22(5):593-603
In northern Western Ghats (India), four tropical habitats with different disturbance levels were monitored for diversity and
seasonal patterns in butterfly communities. Species richness was highest in late monsoon and early winter. Majority of the
butterfly species also showed abundance peaks in these seasons. Fire played a significant role in determining species composition
in fire-afflicted areas and affected flight periods of some species but did not affect species richness. Grazing had a major
impact on species composition and it favoured only those Lycaenids and Nymphalids whose caterpillars feed on herbs. In case
of one of the sites where phenophases of the larval foodplant and population trend of a small Lycaenid was documented, the
population showed rapid increase at the time when the plants were in suitable phenophase for growth of the caterpillars. A
possible evolutionary interaction between herb-feeding and non-herb-feeding Lycaenids is proposed. 相似文献
19.
X. Preville P. Mehlen N. Fabre-Jonca S. Chaufour C. Kretz-Remy M. R. Michel A. -P. Arrigo 《Journal of biosciences》1996,21(2):221-234
The α-crystallin-related stress protein HSP27, which promotes cellular resistance to different types of stress, is constitutively
expressed during the growth of several primate tissue culture cells. Here, we report an analysis of the cellular localization
of this protein in CV-1 monkey cells. Following cell lysis and fractionation in the absence of detergent about 2 5 % of the
cellular content of HSP27 was recovered in the particu late fractions while the remaining of this protein was in the soluble
cytoplasmic fraction. This association of HSP27 with particulate fractions was no more observed when cells were lysed in the
presence of non-ionic detergent or when cells were pretreated with drugs, such as monensin and colcemid, that disrupt cytoskeletal
architecture. Immunofluorescence analysis revealed that HSP27 is concentrated in a polarized perinuclear zone of CV-1 cells
from where microtubules radiate. The particular locale of HSP27 was investigated in cells exposed to drugs or treatments,
such as monensin, colcemid, cold stess and serum starvation, that disrupt the cellular architecture of microtubules. A correlation
was observed between HSP27 cellular locale and microtubules integrity. Our results suggest a possible interaction of a fraction
of HSP27 with cytoplasmic organelles or structures, different from the Golgi apparatus, whose distribution depends upon the
organization of microtubules. 相似文献
20.
Evolutionary conservation of angiosperm flower development at the molecular and genetic levels 总被引:7,自引:0,他引:7
John L. Bowman 《Journal of biosciences》1997,22(4):515-527
Flowers consist primarily of four basic organ types whose relative positions are universally conserved within the angiosperms.
A model has been proposed to explain how a small number of regulatory genes, acting alone and in combination, specify floral
organ identity. This model, known widely as the ABC model of flower development, is based on molecular generic experiments
in two model organisms,Arabidopsis thaliana
and
Antirrhinum majus.Both of these species are considered to be eudicots, a clade within the angiosperms with a relatively conserved floral architecture.
In this review, the application of the ABC model derived from studies of these typical eudicot species is considered with
respect to angiosperms whose floral structure deviates from that of the eudicots. It is concluded that the model is universally
applicable to the angiosperms as a whole, and the enormous diversity seen among angiosperms flowers is due to genetic pathways
that are downstream, or independent, of the genetic programme that specifies floral organ identity. 相似文献