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51.
The role of inflammatory mediators in dental pulp is unique. The local environment of pulp responds to any changes in the physiology that are highly fundamental, like odontoblast cell differentiation and other secretory activity. The aim of this review is to assess the role of cathelicidins based on their capacity to heal wounds, their immunomodulatory potential, and their ability to stimulate cytokine production and stimulate immune-inflammatory response in pulp and periapex. Accessible electronic databases were searched to find studies reporting the role of cathelicidins in pulpal inflammation and regeneration published between September 2010 and September 2020. The search was performed using the following databases: Medline, Scopus, Web of Science, SciELO and PubMed. The electronic search was performed using the combination of keywords “cathelicidins” and “dental pulp inflammation”. On the basis of previous studies, it can be inferred that LL-37 plays an important role in odontoblastic cell differentiation and stimulation of antimicrobial peptides. Furthermore, based on these outcomes, it can be concluded that LL-37 plays an important role in reparative dentin formation and provides signaling for defense by activating the innate immune system.  相似文献   
52.
Gingivitis is the most common form of oral disease especially among patients undergoing fixed orthodontic treatment. Green tea, which is extensively used in Asian countries, can help to improve the overall gingival health, which can be assessed by using the gingival indices. Evaluation of the effectiveness of green tea on the gingival health of patients undergoing Orthodontic treatment is of interest. 40 otherwise healthy patients undergoing fixed orthodontic treatment were randomly divided in two groups namely (1) study group and (2) control group. Gingival indices were scored for all the patients. Study group was given mouth rinse with green tea extract and control group was given placebo with no green tea extract. Gingival indices were measured for all the patients after 21 days. Mann Whitney U test and Wilcoxon test was used for statistical analysis. The gingival indices scoring in which the values before and after the use of mouthwash were compared. The p value was found to be statistically significant (p<0.05) in study group. But in control group statistical significant could not be reached.  相似文献   
53.
Effect of sublethal concentration of B. thuringiensis on the first, third, fourth and fifth instar larvae of the American bollworm, H. armigera was investigated to study their response to food consumption, digestion, utilization, and their development till adult formation. The young larvae surviving B. thuringiensis treatment in their first instar and third instar delayed larval period by two to three days, but did not consume more food as compared to control. However, they showed higher digestibility of food as compared to control, which was compensated by their reduced ability to utilize the digested food for body substance. Contrary to the effect on first and third instar larvae, the fifth instar larvae surviving B. thuringiensis treatment in its fourth instar consumed less food, showed less absorption efficiency in digesting food, but compensated by increase in the utilization of ingested and digested food into body substance. Insects surviving B. thuringiensis HD-1 sublethal toxicity adapted to normal larval growth when fed on untreated food, depending upon insect growth prior to treatment. The moths emerging from B.thuringiensis treated larvae had sex ratio favouring females, and adult pairs laid less fertile eggs than those from the untreated ones. The response of B. thuringiensis treated larvae to their food and developmental needs is discussed.  相似文献   
54.
Effect of fructose 1,6-diphosphate (FDP) and carbon tetrachloride (CCl4) were studied individually and in combination on rat endothelial (ET) and smooth muscle cell (SMC) nitric oxide synthase (NOS) activities in vivo, inhibition of ET and SMC NOS activity in CCl4 treated rats was reversed in FDP + CCl4 treated animals. Cellular based NOS activity was significantly increased in FDP treated group of rats when compared to non treated controls. The results suggest a significant increase in NOS in rats treated with a combination of FDP + CCl4 thus overcoming the suppression of NOS exposed to CCl4 alone.  相似文献   
55.
We have characterized the biochemical association of two DNA damage-dependent enzymes, poly(ADP-ribose) polymerase-1 (PARP-1) [EC 2.4.2.30] and DNA polymerase beta (pol beta) [2.7.7.7]. We reproducibly observed that pol beta is an efficient covalent target for ADP-ribose polymers under standard conditions of enzymatically catalyzed ADP-ribosylation of betaNAD+ as a substrate. The efficiency of poly(ADP-ribosyl)ation increased as a function of the pol beta and betaNAD+ concentrations. To further characterize the molecular interactions between these two unique polymerases, we also subjected human recombinant PARP-1 to peptide-specific enzymatic degradation with either caspase-3 or caspase-7 in vitro. This proteolytic treatment, commonly referred to as 'a hallmark of apoptosis', generated the two physiologically relevant peptide fragments of PARP-1, e.g., a 24-kDa amino-terminus and an 89-kDa carboxy-terminal domain. Interestingly, co-incubation of the two peptide fragments of PARP-1 with full-length pol beta resulted in their domain-specific molecular association as determined by co-immunoprecipitation and reciprocal immunoblotting. Therefore, our data strongly suggest that, once PARP-1 is proteolyzed by either caspase-3 or caspase-7 during cell death, the specific association of its apoptotic fragments with DNA repair enzymes, such as pol beta, may serve a regulatory molecular role in the execution phase of apoptosis.  相似文献   
56.
Ethanolic extract of flowers of Pongamia pinnata was studied for its protective effect against cisplatin and gentamicin induced renal injury in rats. When the extract (300 & 600 mg kg(-1)) was administered orally for 10 days following cisplatin (5 mg kg(-1) i.p.) on day 5, toxicity of cisplatin, as measured by loss of body weight, elevated blood urea and serum creatinine declined significantly. Similarly in gentamicin (40 mg kg(-1) s.c.) induced renal injury, the extract (600 mg kg(-1)) normalized the raised blood urea and serum creatinine levels. Reversal of cisplatin and gentamicin renal cell damage as induced by tubular necrosis ie, marked congestion of the glomeruli with glomerular atrophy, degeneration of tubular epithelial cells with casts in the tubular lumen and infiltration of inflammatory cells in the interstitium was confirmed on histopathological examination. In the preventive regimen, co-administration of the extract with gentamicin significantly prevented the renal injury both functionally and histologically. Ethanolic extract of flowers had a marked nitric oxide free radical scavenging effect, suggesting an antioxidative property. Two flavonoids, known for their antioxidant activity viz. kaempferol and 3, 5, 6, 7, 8-pentamethoxy flavone were isolated from the extract. The results suggested that the flowers of Pongamia pinnata had a protective effect against cisplatin and gentamicin induced renal injury through antioxidant property.  相似文献   
57.

Background

The function of proteins is a direct consequence of their three-dimensional structure. The structural classification of proteins describes the ways of folding patterns all proteins could adopt. Although, the protein folds were described in many ways the functional properties of individual folds were not studied.

Results

We have analyzed two β-barrel folds generally adopted by small proteins to be looking similar but have different topology. On the basis of the topology they could be divided into two different folds named SH3-fold and OB-fold. There was no sequence homology between any of the proteins considered. The sequence diversity and loop variability was found to be important for various binding functions.

Conclusions

The function of Oligonucleotide/oligosaccharide-binding (OB) fold proteins was restricted to either DNA/RNA binding or sugar binding whereas the Src homology 3 (SH3) domain like proteins bind to a variety of ligands through loop modulations. A question was raised whether the evolution of these two folds was through DNA shuffling.  相似文献   
58.
Vitamin A and its derivatives inhibit normal tail regeneration in amphibians. The most remarkable effect is the development of limbs at the cut end of the tail in anurans. Prior to ectopic limb development, there is an abnormal tail regeneration in the treated tadpoles. The purpose of the present study was to compare oxidative stress condition in the regenerated tail of normal and vitamin A (10I U/ml, 72 h) treated tadpoles. The present findings show a hyper-oxidative stress condition in the regenerated tail of the vitamin A-treated tadpoles of the Indian jumping frog, Polypedates maculatus (Anura: Rhacophoridae).  相似文献   
59.
The genus Amycolatopsis is of industrial importance, as its species are known to produce commercial antibiotics. It belongs to the family Pseudonocardiaceae and has an eventful taxonomic history. Initially strains were identified as Streptomyces, then later as Nocardia. However, based on biochemical, morphological and molecular features, the genus Amycolatopsis, containing seventeen species, was created. The development of molecular genetic techniques for this group has been slow. The scarcity of molecular genetic tools including stable plasmids, antibiotic resistance markers, transposons, reporter genes, cloning vectors, and high efficiency transformation protocols has made progress slow, but efforts in the past decade have led to the development of cloning vectors and transformation methods for these organisms. Some of the cloning vectors have broad host range (pRL series) whereas others have limited host range (pMEA300 and pMEA100). The cloning vector pMEA300 has been completely sequenced, while only the minimal replicon (pA-rep) has been sequenced from pRL plasmids. Direct transformation of mycelia and electroporation are the most widely applicable methods for transforming species of Amycolatopsis. Conjugational transfer from Escherichia coli has been reported only in the species A. japonicum, and gene disruption and replacements using homologous recombination are now possible in some strains. Electronic Publication  相似文献   
60.
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