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921.
Interleukin (IL-)1 is an important mediator of inflammatory responses and plays an important role in the pathogenesis of various autoimmune diseases. Cicatricial pemphigoid (CP) is a multisystem autoimmune inflammatory disease. We have studied the role of IL-1 in its pathogenesis. We have investigated the serum levels of IL-1 components (IL-1alpha, IL-1beta, and IL-1Ra), and determined the role of intravenous immunoglobulin (IVIg) therapy in patients with CP. Serum levels of IL-1alpha and beta were significantly higher in untreated patients with active disease compared to levels in patients in prolonged clinical remission and normal human controls (P<0.0001). The serum levels of IL-1Ra were higher in patients in prolonged clinical remission compared to patients with active disease (P=0.002). Hence elevated levels of IL-1alpha and beta and low levels of IL-1Ra correlate with disease activity. The levels of IL-1alpha and beta were statistically significantly higher in sera of CP patients with active disease pre-IVIg therapy compared to post-IVIg therapy (P<0.0001). Statistically significantly higher levels of IL-1Ra were present in post-IVIg treatment serum samples when compared to levels in pre-IVIg treatment (P<0.0001). In the in vitro experiments, the levels of IL-1alpha and beta produced by the peripheral blood mononuclear cells (PBMC) isolated from patients before IVIg therapy were significantly higher when compared to the PBMC isolated from post-IVIg patients (P<0.0001). Significantly higher levels of IL-1Ra were observed in the supernatants of PBMC collected from pre-IVIg patients and cultured with exogenously added IVIg, when compared to the levels of PBMC to which IVIg was not added (P<0.0001). IL-1 may be an important cytokine involved in the pathogenesis of CP. The regulation of IL-1 could be one of the mechanisms, amongst others, by which IVIg may exert its beneficial effect in the treatment of CP. 相似文献
922.
Both the Entamoeba histolytica lectin, a virulence factor for the causative
agent of amebiasis, and the mammalian hepatic lectin bind to
N-acetylgalactosamine (GalNAc) and galactose (Gal) nonreducing termini on
oligosaccharides, with preference for GalNAc. Polyvalent GalNAc-
derivatized neoglycoproteins have >1000-fold enhanced binding affinity
for both lectins (Adler,P., Wood,S.J., Lee,Y.C., Lee,R.T., Petri,W.A.,Jr.
and Schnaar,R.L.,1995, J. Biol. Chem ., 270, 5164-5171). Substructural
specificity studies revealed that the 3-OH and 4-OH groups of GalNAc were
required for binding to both lectins, whereas only the E.histolytica lectin
required the 6-OH group. Whereas GalNAc binds with 4-fold lower affinity to
the E.histolytica lectin than to the mammalian hepatic lectin,
galactosamine and N-benzoyl galactosamine bind with higher affinity to the
E. histolytica lectin. Therefore, a synthetic scheme for converting
polyamine carriers to poly-N-acyl galactosamine derivatives (linked through
the galactosamine primary amino group) was developed to test whether such
ligands would bind the E.histolytica lectin with high specificity and high
affinity. Contrary to expectations, polyvalent derivatives including
GalN6lys5, GalN4desmosine, GalN4StarburstTMdendrimer, and
GalN8StarburstTMdendrimer demonstrated highly enhanced binding to the
mammalian hepatic lectin but little or no enhancement of binding to the
E.histolytica lectin. We propose that the mammalian hepatic lectin binds
with greatest affinity to GalNAc "miniclusters," which mimic branched
termini of N-linked oligosaccharides, whereas the E.histolytica lectin
binds most effectively to "maxiclusters," which may mimic more widely
spaced GalNAc residues on intestinal mucins.
相似文献
923.
Important parameters in the regeneration of protoplasts are viability, the capacity to synthesize cell walls and the retention of properties of the parent cell. Mycelial protoplasts of Trichoderma longibrachiatum (Trichoderma reesei) have been regenerated. Factors influencing the regeneration of protoplasts of T. longibrachiatum QM 9414 were found to be, the nature of osmotic stabilizer, the concentration of osmotic stabilizer, pH, temperature, and the composition of regeneration medium. With glucose-mineral regeneration medium, the optimum conditions for protoplasts regeneration were 0.5 M KCl, pH 6.0 and temperature 30°C. With Czapek-Dox medium, the optimum conditions were 0.7 M mannitol, pH 6.0 and temperature 30°C. Maximum regeneration frequency of T. longibrachiatum protoplasts were obtained using glucose-mineral medium. 相似文献
924.
Neeraj Kumari Manoj Kumar Nisha Chaudhary Baohong Zhang Radha Deepak Chandran Shourabh Joshi Daljeet Singh Abhijit Dey Sureshkumar Rajalingam Krishnaprabu Natarajan Muthamilselvan Muthukumar Pran Mohankumar Vijay Sheri Sangram Dhumal Jose M. Lorenzo 《化学与生物多样性》2023,20(9):e202300479
Leaves of jamun collected as agro by-produce during the cultivation of jamun is traditionally used as ayurvedic medicine to treat diabetes, gall bladder stones and other ailments. Most of the beneficial effects of jamun leaves are associated with phytochemicals found in jamun leaves such as gallic acid, tannins, mallic acid, flavonoids, essential oils, jambolin, ellagic acid, jambosine, antimellin and betulinic acid. Jamun possess curative activities like anticancer, antidiabetic, antifertility, anti-inflammatory, antidiarrheal, antimicrobial, antinociceptive, antioxidant, antiradiation, chemotherapeutic, and gastroprotective. The main goal of this review article is to provide information on the nutritional content, phytochemical composition and health promoting properties of jamun leaves. The review of literature based on the phytochemical composition and health promoting benefits of the jamun leaves, suggests that leaves can be used as potential constituent in the formulation of pharmacological drugs. From the review literature it is found that clinical, in-vivo, in-vitro studies are still required to check the health promoting effects of jamun leaves extracts on humans. 相似文献
925.
926.
Khar A Pardhasardhi BV Varalakshmi C Ali AM Kumari AL 《Apoptosis : an international journal on programmed cell death》1997,2(6):494-500
AK-5 tumour cells have been shown to undergo apoptosis in vitro and in vivo. The efficient killing of tumour cells by necrosis
and apoptosis leads to spontaneous regression of the tumour. To investigate a possible involvement of caspase-2/Nedd-2 protease
in AK-5 apoptosis, we introduced Nedd-2 gene in antisense orientation and showed inhibition of tumour cell apoptosis. Similarly
introduction of the bcl-2 gene in tumour cells also inhibited the apoptotic programme. NK cells which have previously been
shown to be the effector cells also fail to induce apoptosis in Nedd-2 antisense and bcl-2 transfected clones whereas NK mediated
cytotoxic activity is not altered in the transfectants. These results suggest participation of Nedd-2 protease in the induction
of apoptosis in AK-5 cells leading to tumour regression.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
927.
George Britton Raj Kumari Singh Harish C. Malhotra Trevor W. Goodwin Avraham Ben-Aziz 《Phytochemistry》1977,16(10):1561-1566
The effects of the inhibitors diphenylamine (DPA), 2-(4-chlorophenylthio) triethylammonium chloride (CPTA) and nicotine on the biosynthesis of 1,2-dihydrocarotenoids by Rhodopseudomonas viridis (Rhodospirillaceae) have been investigated. Small amounts of 1,2-dihydro derivatives of phytoene, phytofluene and ξ-carotene and its unsymmetrical isomer, and 1,2,1′,2′,-tetrahydro derivatives of neurosporene and lycopene were isolated from R. viridis grown in the presence of DPA, although there was virtually no quantitative effect on the levels of the normal main carotenoids, neurosporene and lycopene and their 1,2-dihydro derivatives. Nicotine also had little effect on the overall carotenoid composition, but the formation of 1,2-dihydrocarotenoids was inhibited to some extent by CPTA. The 1,2-dihydro end group may thus be introduced by a hydrogenation reaction similar to the more familiar C-1,2 hydration reaction characteristic of carotenoid biosynthesis in other photo synthetic bacteria. 相似文献
928.
929.
Rup Lal Mandeep Dadhwal Kirti Kumari Pooja Sharma Ajaib Singh Hansi Kumari Simran Jit Sanjay Kumar Gupta Aeshna Nigam Devi Lal Mansi Verma Jaspreet Kaur Kiran Bala Swati Jindal 《Indian journal of microbiology》2008,48(1):3-18
The unusual process of production of hexachlorocyclohexane (HCH) and extensive use of technical HCH and lindane has created
a very serious problem of HCH contamination. While the use of technical HCH and lindane has been banned all over the world,
India still continues producing lindane. Bacteria, especially Sphingomonads have been isolated that can degrade HCH isomers.
Among all the bacterial strains isolated so far, Sphingobium indicum B90A that was isolated from HCH treated rhizosphere soil appears to have a better potential for HCH degradation. This conclusion
is based on studies on the organization of lin genes and degradation ability of B90A. This strain perhaps can be used for HCH decontamination through bioaugmentation. 相似文献
930.
Giridara-Kumar Surabhi Alavala Matta Reddy Gottimukkala Jyothsna Kumari Chinta Sudhakar 《Environmental and Experimental Botany》2008,64(2):171-179
Effect of salinity stress on the performance of nitrogen metabolism was studied in two high yielding genotypes of mulberry with differential sensitivity to NaCl (S1 and ATP, salt tolerant and susceptible, respectively). Three-month-old healthy mulberry plants were subjected to different regimes of NaCl stress [0.0 (control), 0.5, 1.0 and 1.5% NaCl] and leaf samples were collected on 4, 8 and 12 DAT (days after treatment) for the analysis. The activities of nitrate reductase (NR: EC 1.6.6.1), nitrite reductase (NiR: EC 1.6.6.4), protease, glutamine synthetase (GS: EC 6.3.1.2) and its accumulation pattern, glutamate synthase (GOGAT: EC 1.4.1.13), glutamate dehydrogenase (NADH-GDH: EC 1.4.1.2 and NADPH-GDH: EC 1.4.1.4), aspartate aminotransferase (AAT: EC 2.6.1.1) and alanine aminotransferase (ALAT: EC 2.6.1.2) coupled with total protein content, free amino acid level and ammonia content were studied in leaves of both genotypes of mulberry. The total protein content in leaves of both genotypes declined with progressive accumulation of free amino acid levels. Further, the decrease in protein content was less in S1 than ATP, and it was correlated with protease activity, ammonia content and accumulation of free amino acid levels. Higher free amino acid levels were registered for S1 than ATP at 1.0 and 1.5% NaCl stress and on all days of sampling. Ammonia content was increased in both genotypes and comparatively higher ammonia levels were recorded for ATP. Increased NaCl concentrations lead to a decrease in the activity of NR and NiR in both the genotypes, the decrease was more pronounced in ATP than S1. The enhanced activity of GDH (NADH and NADPH) was noticed in both genotypes, whereas the NADPH-GDH activity was found relatively higher in S1. The immunoblot analysis with GS-45 antibodies revealed a specific cross-reaction with 42 and 45 kDa proteins in S1, and only 45 kDa protein in ATP genotype. However, increased GS protein accumulation pattern (both 42 and 45 kDa) was observed in S1 under high NaCl. Whereas, accumulation of 45 kDa protein was unchanged at all levels of stress and slight accumulation in 42 kDa protein at 1.5% NaCl was observed for ATP. Elevation in the enzyme activities of GS, GOGAT were coupled with AAT and ALAT observed in both the genotypes. Higher enzymatic activities of S1 than ATP under salinity stress may be due to efficient capacity of ammonia detoxification. Salt tolerance of S1 supports the higher metabolic activity under salinity leading to lesser amount of ammonia accumulation and higher levels of free amino acid in the tissue. In agreement with these results the physiological significance of enzymatic changes and ammonia assimilation during salt stress in relevance to plant nitrogen metabolism was discussed. 相似文献