Turmeric (Curcuma longa Linn.) which is cultivated by underground rhizomes is a slow propagating species. Multiplication and callus induction starting from the rhizome buds and shoot tips of C. longa in MS medium was carried out. A combination of naphthalene acetic acid (NAA; 1.0 mg/l) with kinetin (Kn; 1.0 mg/l) or NAA (1.0 mg/l) with 6-benzylaminopurine (BAP; 2.0 mg/l) was optimum for rapid clonal propagation of turmeric. A concentration of 2.5-3.0 mg/l of 2,4-dichlorophenoxy-acetic acid (2,4-D) was found to be optimum for callus induction. Regeneration of plantlets from a callus was successfully conducted in MS medium supplemented with standard growth hormones for multiplication at 25 +/- 2 degrees C under a 16 h photoperiod. These plantlets were successfully transferred to the field. Plantlets (4-month-old) were incubated in a medium containing different concentrations of sucrose supplemented with NAA (0.1 mg/l) and Kn (1.0 mg/l) at 27 +/- 2 degrees C under an 8 h photoperiod for induction of rhizomes. In vitro rhizome formation was observed in media containing 6 and 8% sucrose.
Characterization of hereditary persistence of foetal haemoglobin (HPFH) mutation in a family from West Bengal, India, was carried out by analysing the structure of the 5 ' -G-y-A gamma-psi beta-delta-beta -3 ' globin gene region by using the restriction fragment length polymorphism-polymerase chain reaction (RFLP-PCR) technique. The HPFH in this family was due to a deletion in the beta -globin gene cluster spanning at least from the Hin cll/5 ' psi beta to the Hin fl/3 ' beta RFLP site. This work indicates the importance of RFLP-PCR technique in characterization of the HPFH mutation.
The effects of three subcutaneous injections of 3 nmol/100 g body weight of the cholecystokinin type 2 (CCK2) receptor agonist pentagastrin on adrenocorticotrophic hormone (ACTH) and corticosterone secretion and proliferative activity of regenerating rat adrenal cortex were investigated. Pentagastrin did not alter either ACTH and corticosterone plasma concentrations or the adrenal mitotic index at day 5 of regeneration. In contrast, it increased (by about 50%) the adrenal mitotic index at day 8 of regeneration, and the effect was blocked by the simultaneous administration of equimolar doses of the CCK2-receptor antagonist PD-135,158. It is suggested that the activation of CCK2 receptors exerts a growth promoting action on the regenerating rat adrenal cortex.
Seven fungi were tested for production of mannanases. The highest mannanase activities were produced by Aspergillus oryzae NRRL 3488 after 7 days in static cultures. Mannanases were induced by gum locust bean (1.0%). The highest mannanase activity was produced when a mixture of peptone, urea and ammonium sulphate was used as nitrogen source. Zn2+ or Co2+ favoured enzyme production. The immobilized cells on Ca-alginate and agar were able to produce beta -mannanase for four runs with a slight decrease in the activity. The optimum temperature for enzyme reaction was 50-55 degreesC at pH 6.0. In the absence of substrate the enzyme was thermostable retaining 75% activity for 1 h at 50 degreesC, and 68% activity for 1 h at 60 degreesC.
Kidneys are not only organs with an excretory function but they produce their own endocrine factors which are involved in supporting homeostasis in the organism. The kidneys are the organs in which metabolism and biodegradation of many hormones take place. Together with the liver, the kidneys actively take part in the catabolism of hormones.
The effects of white light and UV light on chromosome endoreduplication, chromatin conformation and RNA synthesis were analysed in the hypocotyl cortical cylinder of the cv UC-105 of tomato and its isogenic mutant aurea, deficient in photoactive phytochrome A at the etiolated stage. Short white light or UV irradiations were administered to 4-day-old seedlings grown in the dark. White light had no effect on the mean ploidy level in the cv UC-105, but it increased the ploidy level in the aurea mutant. This is explained by hypothesizing that phytochrome inhibits endoreduplication, while cryptochrome stimulates it. UV light produced a higher ploidy in both genotypes, possibly because of residual action of cryptochrome at this wavelength or of specific UV-responsive photoreceptor. White light or UV light transiently increased heterochromatin amounts in the diploid nuclei of cv UC-105, and produced higher levels of RNA transcription than continuous dark. It is suggested that these responses were mediated by phytochrome, because they were lacking in the aurea mutant.
Following exposure of rats to the arylamine carcinogen 2-aminofluorene, DNA-carcinogen adducts were found in the liver and bladder target tissues, and also in circulating leucocytes. This work investigated the effect of ellagic acid on arylamine (2-aminofluorene and p-aminobenzoic acid) acetylations in rat leucocytes. Evidence is presented that rat mononuclear leucocytes are capable of acetylating 2-aminofluorene and p-aminobenzoic acid. Both lymphocytes and monocytes were able to acetylate arylamines during 18 h of culture. Cultured lymphocytes produced about twice as much N-acetyl-2-aminofluorene from 2-aminofluorene and 2.2-fold as much N-acetyl-p-aminobenzoic acid from p-aminobenzoic acid as monocytes. After cotreatment with ellagic acid the lymphocyte and monocyte cultures indicated that ellagic acid reduced 2-aminofluorene acetylation.
The antimutagenic effects of the two enantiomers of centchroman, a nonsteroidal oral contraceptive, were evaluated and compared with tamoxifen, a known breast cancer drug. Anticlastogenic assays in subacute in vivo studies in Swiss albino mice were used. They revealed that both d-centchroman and I-centchroman reduced the chromosome aberrations produced by dimethylbenz(a)anthracene and cyclophosphamide, when compared with the group treated only with the former mutagen. Tamoxifen also reduced the chromosome aberrations produced by the two mutagens. Overall the results showed that l-centchroman alone was more effective in reducing cyclophosphamide-induced aberrations than d-centchroman, and for toxicity reasons may be an alternative to tamoxifen in breast cancer therapy.
Serum triacylglycerides and total cholesterol levels in rats, with hyperlipidaemia induced by diet, were determined after oral adminstration of a water extract of Anethum graveolens leaves before and after the extraction of the furocoumarin content of the leaves. Administration of the extracts consecutively for 14 days reduced the triacylglycerides and total cholesterol levels by almost 50 and 20%, respectively. Chloroform extraction of furocoumarins from the aqueous extracts did not reduce the antihyperlipidaemic potential of the extracts to a significant degree. Oral administration of the essential oil of A. graveolens seeds, at two different doses, also reduced the triacylglyceride levels by almost 42%. The total cholesterol level was not reduced by the same doses of the essential oil.
This is the first karyotype characterization of Brachiaria species. Twelve accessions belonging to five species were analysed. The basic chromosome number was x = 9 and 7, the same reported for the tribe Paniceae. Variations in the chromosome number were observed in B. decumbens (2n = 18; 36) and B. humidicola (2n = 36; 42; 54). Chromosome numbers of 2n = 18 in B. ruziziensis and 2n = 36 in B. brizantha and B. jubata were recorded. Inter- and intraspecific karyotype differentiation of the accessions analysed was facilitated by variations in karyotypic symmetry. The karyotypes were generally considered symmetrical, with a tendency to asymmetry in the direction of the polyploids. It is suggested that addition, deletions and mainly polyploidy have been the most direct causes involved in the chromosome evolution of this genus.
Immunofluorescence microscopy revealed that nonmuscle myosin and cardiac muscle-specific myosin were present in the myofibrils of cultured adult cardiac muscle cells at different stages of redifferentiation including fully redifferentiated cells. Nonmuscle myosin and cardiac muscle-specific myosin were observed in amorphous or fibroamorphous form predominantly in unspread and partially spread cardiac myocytes. Nonmuscle myosin and cardiac muscle-specific myosin were present in the same striated myofibrils of the same fully redifferentiated cells. Nonmuscle myosin was localized in the Z-lines of sarcomeres of myofibrils. In double stained cells, alpha-actinin was colocalized with nonmuscle myosin in the Z-lines. The in vivo adult cardiac muscle cells contained nonmuscle myosin and cardiac muscle-specific myosin in the same myofibrils of the same cells with the localization of nonmuscle myosin in Z-lines and intercalated discs. It is evident that the nonmuscle myosin is an integral part of the sarcomeric structure of myofibrils in cardiac muscle cells.
Several fitness components in strains of Drosophila mulleri carrying the slow or the fast alleles for the major beta esterase (esterase-4) found in this species, as well as in heterozygous flies in which the slow or fast alleles came from one of the parents, were evaluated. Twelve components were analysed including longevity of both virgins and mated males and females, productivity, viability, including the egg-larva, egg-pupa, egg-imago and pupa-imago periods. These parameters were used to estimate the total fitness for each genotype. The best score was reached by individuals having the Est-4(S)/Est-4(S) genotype (scored at 1.000), followed by a fitness value of 0.892 presented by the Est-4(F)/Est-4(S) genotype (with the fast allele from maternal origin), 0.863 for the Est-4(F)/Est-4(F) and 0.842 for the Est-4(S)/Est-4(F) genotypes (with Est-4(F) maternal origin). These results suggested a higher relative adaptability of the Est-4(S)/Est-4(S) genotype followed by the Est-4(F)/Est-4(S) hybrid that possessed the allele Est-4(S) of maternal origin, which was incompatible with predictions of neutral polymorphism.
Cyclins and wild-type p53 protein are prime cell cycle regulators and may be involved in tumorigenesis. Cyclin A is a late S cyclin and its abnormalities have been reported in several cancers, including oral squamous cell carcinomas. To explore whether aberrant G(1)/S in p53 mutant tumours leads to increased cyclin A protein in oral squamous cell carcinomas (OSCC), a total of 39 samples were evaluated for the expression of cyclin A and p53 protein by an immunohistochemical method using a labelled polymer assay. These samples comprised two hyperkeratotic and three oral premalignant lesions (two moderate and one severe dysplastic lesions), and 27 OSCC, together with seven healthy controls. The results demonstrated that the cyclin A protein was localized and highly expressed in the nuclei of the tumour cells. Although there was no correlation between cyclin A detection and the local lymph node involvement, a positive correlation was noted between the positivity of cyclin A and p53 protein (p <0.05). The results suggested that cyclin A may contribute to the progression of oral cancer and correlated to some degree with that of the p53 gene activity.
The oral administration of a soxhlated crude ethanolic extract of leaves of neem (Azadirachta indica Ajuss; family Meliaceae) to adult male mice for 6 weeks (one spermatogenic duration) at the rate of 0.5, 1.0 or 2.0 g/kg body weight per day increased the incidences of structural changes and synaptic-disturbances in meiotic chromosomes and also caused more disruptions of meiosis. The extract reduced the sperm count and increased the frequency of spermatozoa with abnormal head morphology. It is suggested that at least one of the constituents of the extract may have interfered with the DNA. The result was chromosome strand breakages, or spindle disturbances, and the regulation of genes responsible for sperm shaping was affected.
Scanning electron microscopy revealed that the cellular and morphological defects in the integument of Channa punctatus, associated with heavy metal and other environmental pollution was related to a significant extent to the hydrogen ion concentration of the water. At low pH, the epidermis showed severe lesions, and the scale lost its attachment with the skin, due to lepidontal alterations of the circuli. Atomic absorption spectroscopic analysis of the tissue indicated disturbances in the homeostasis of several elements, which probably played a major role in causing the cellular and morphological defects. Experimental monitoring of the pH of the polluted water to near-neutral, reduced significantly the extent of cellular and morphological defects and disturbances in elemental homeostasis.
The in vitro generation of reactive oxygen species (ROS) in haemocytes of Galleria mellonella, Aporia crataegi, Dendrolimus sibiricus, Aglais urticae (Lepidoptera) and Gryllus bimaculatus (Orthoptera), was studied by the method of nitroblue tetrazolium (NBT) reduction. Formazan formation (product of NBT reduction) was observed in haemocytes of all the insects examined, except A. urticae. Lypopolysaccharide and zymosan reduced the number of NBT-positive cells after 1 h incubation and an increase was registered after 4 h incubation. The inhibitors of the respiratory chain enzyme (sodium azide) and melanogenesis (phenylthiourea) reduced formazan formation in nonactivated insect blood cells. No influence of sodium azide and phenylthiourea was found on the activated haemocytes. The results suggest that the generation of ROS in insect haemocytes occured as a result of processes such as respiration and melanization during phagocytosis and encapsulation.
Vero cells, a fibroblastic lineage derived from fibroblastic kidney cells of the African green monkey, were cultivated by means of the sandwich technique, involving glass coverslip/collagen and collagen/collagen with varied foetal calf serum concentrations in the culture medium. The cells, cultured on coverslips, then received a type I collagen gel layer on top, and migrated from the coverslip to the collagen layer. When the cells were cultivated on collagen followed by a covering of type I collagen gel, the cells migrated into both collagen layers. Cellular morphology was similar, independent of the type of sandwich and serum concentration used. Cells in contact with collagen either migrated into the layer or formed a basal lamina separating them from the collagen matrix. The formation of a basal lamina with laminin and collagen IV deposition was most noticeable when 20% foetal calf serum was used in the culture medium. Cellular infiltration into the collagen gel was most evident with the use of 10% foetal calf serum. The gel contraction was similar for the two serum concentrations employed.
These conserved nuclear enzymes catalyse a variety of interconversions of DNA which take place between topological isoforms of the molecule, through transient cleavage, strand passing and re-ligation. In this context the DNA topoisomerases have been generally considered as good candidates to play a role in the enzymatic repair processes going on in the cell after DNA damage inflicted by either physical or chemical agents. It has been suggested that this role could be direct, with the actual participation of topoisomerases in the molecular mechanism of lesion repair, as for example in the excision of base damage or DNA strand break repair. Alternatively, it could be indirectly responsible for the preparative steps in the relaxation of chromatin in order to allow repair enzymes to gain access to damaged DNA.
The epidermis and dermis of albino mice born to females receiving oral sublethal doses of lead during pregnancy developed several abnormalities. These included perforations, tissue damage, cell deformity, and disordered organization of collagen bundles, as revealed by scanning electron microscopy. An increase in the concentrations of zinc, iron, magnesium, calcium and a decrease in that of copper was evident from atomic absorption spectroscopical analysis, when entire skin tissues were examined. Infrared spectroscopy revealed the occurrence of split bands in the spectra at 1,200-1,000 cm(-1), suggesting a reduction in the symmetry of the sulphate group (glycosaminoglycans) of skin probably caused by covalent bonding of it with lead.
Spermiogenesis in the bufonid Melanophryniscus cambaraensis was analysed ultrastructurally. The nucleus of spermatids undergoes morphological modifications divided into five distinct stages based on chromatin condensation. The acrosomal vesicle differentiates into an acrosome and a subacrosomal cone, which cap the anterior region of the nucleus. The spermatozoa consist of the head with a nucleus and acrosomal complex and the tail, with an axoneme, an axial rod and an undulating membrane. The participation of several carbohydrate moieties during this differentiation process was detected using various gold-labelled lectins.
