A supernumerary tooth is that which is present additionally to the normal series and can be found in any region of the dental arch. An impacted tooth is defined as the one which is embedded in the alveolus, so that its eruption is prevented, or the tooth is locked in position by bone or the adjacent teeth. The occurrence of multiple supernumerary teeth in only one patient in the absence of an associated systemic condition or syndrome is considered as a rare phenomenon. The occurrence of supernumerary teeth in the lower molar region is rare. A prevalence of less than 2% of cases occurring in this region has been estimated. Their occurrence presents a clinical problem for orthodontists and oral surgeons. The cause, frequency, complications, and surgical operation of impacted teeth are always interesting subjects for study and research. An impacted tooth can result in caries, pulp disease, periapical and periodontal disease, temporomandibular joint disorder, infection of the fascial space, root resorption of the adjacent tooth, and even oral and maxillofacial tumours. The management of impacted wisdom teeth has changed over the past 20 years from removal of nonsymptomatic third molars to simple observation. The aim of this paper is to present a rare case of bilateral multiple impacted supernumerary mandibular third molars.
Giant cell granuloma (GCG) is an uncommon bony lesion in the head and neck region, most commonly affecting the maxilla and mandible and has a female predilection. The clinical behavior of central GCG ranges from a slowly growing asymptomatic swelling to an aggressive lesion. The clinical, radiological, histological features and management of an aggressive GCG of maxilla in an 18-year-old female patient are described and discussed. It is emphasized that surgery is the traditional and still the most accepted treatment for GCG. Le Fort I osteotomy has been advocated as one of the access osteotomy for the surgical management of aggressive and extensive GCG involving the maxilla. The postoperative morbidity and recurrence have been discussed.
Giant cell granuloma; Le Fort I access osteotomy; maxillary sinus tumor
The androgen receptor (AR) plays a critical role in the proliferation of prostate cancer cells. However, its mechanism of action in proliferation remains unknown. An understanding of the mechanism of AR action in proliferation may lead to the development of effective strategies for the treatment of prostate cancer.
In this study we report that pulse treatment of synchronized LNCaP cells with Casodex, an AR-antagonist, for 4 hours in mid-G1 phase was sufficient to prevent cells from entering S phase. Since the assembly of pre-replication complex (pre-RC) in G1 is required for the progression of cells from G1 to S phase, the effect of Casodex during mid-G1 suggested that the role of AR in proliferation might be to regulate the assembly of pre-RC. To test this possibility, we investigated the interaction between AR and Cdc6, an essential component of pre-RC in LNCaP cells. AR co-localized and co-immunoprecipitated with Cdc6, and Casodex treatment disrupted this interaction. AR-immunoprecipitate (AR-IP) also contained cyclin E and cyclin A, which play a critical role in pre-RC assembly and cell cycle entry into S phase, and DNA polymerase-α, PCNA, and ribonucleotide reductase, which are essential for the initiation of DNA synthesis. In addition, in cells in S phase, AR co-sedimented with components of the DNA replication machinery of cells that entered S phase.
Together, these observations suggest a novel role of AR as a component of the pre-RC to exert control over progression of LNCaP cells from G1 to S phase through a mechanism that is independent of its role as a transcription factor.
Cataract is a key factor in the morbidity associated with diabetes. While the pathogenesis of diabetic cataract formation is poorly understood, previous research has identified aldose reductase (ALR2) as a key player. To elucidate a potential role for this enzyme in diabetic cataract formation, we created a series of transgenic mice designed for expression of human ALR2 (AKR1B1) in epithelial and outer cortical fiber cells of the lens. One of the founder lines, designated PAR39, developed an early onset cataract that involved formation of a plaque of cells at the anterior aspect of the lens. These cells appear to separate from the anterior epithelium and undergo a dramatic change that is reminiscent of the epithelial to mesenchymal transition (EMT). We characterized this phenotype in the PAR39 strain by examining rates of cell proliferation and by immunostaining for markers of EMT. Incorporation of the thymidine analog bromodeoxyuridine (BrdU) was used to estimate cell proliferation in two functional areas of the lens epithelium: the mitotically active germinative zone (GZ) and the less proliferative center zone (CZ). Staining cell nuclei with diamido 4',6-diamidino-2-phenylindole (DAPI) was used to establish a total cell count in the demarcated areas. Lens epithelium in PAR39 transgenic mice demonstrated a decrease in the percentage of BrdU/DAPI staining within the GZ as compared to nontransgenic littermate controls (8.1% vs. 10.9%). A similar decrease in BrdU/DAPI was observed in the CZ (0.6% compared to 3.3%). However, cell density was greater within the GZ of PAR39 mice as compared with nontransgenic controls, while it was not significantly different in the CZ among the two groups. Furthermore, cells associated with the epithelial plaque did not stain positive for BrdU, but were strongly positive for alpha-smooth muscle actin, a classical marker for EMT. These findings suggest that ALR2 over-expression is associated with an alteration in the balance between proliferation and apoptosis of epithelial cells in the mouse lens, and that cells associated with epithelial plaques in the PAR39 lens have features in common with cells undergoing EMT.
cataract; EMT; epithelial-to-mesenchymal transition; aldo-keto reductase; diabetes
Firefly luciferase-catalyzed light emission from D-luciferin is widely used as a reporter of gene expression and enzymatic activity both in vitro and in vivo. Despite the power of bioluminescence for imaging and drug discovery, light emission from firefly luciferase is fundamentally limited by the physical properties of the D-luciferin substrate. We and others have synthesized aminoluciferin analogs that exhibit light emission at longer wavelengths than D-luciferin and have increased affinity for luciferase. However, although these substrates can emit an intense initial burst of light that approaches that of D-luciferin, this is followed by much lower levels of sustained light output. We have previously postulated that this behavior is due to product inhibition. Here we describe the creation of mutant luciferases that yield improved sustained light emission with aminoluciferins in both lysed and live mammalian cells, allowing the use of aminoluciferins for cell-based bioluminescence experiments.
Retinitis Pigmentosa (RP) is a common form of retinal degeneration characterized by photoreceptor degeneration and retinal pigment epithelium (RPE) atrophy causing loss of visual field and acuities. Exome sequencing identified a novel homozygous splice site variant (c.111+1G>A) in the gene encoding retinol binding protein 4 (RBP4). This change segregated with early onset, progressive, and severe autosomal recessive retinitis pigmentosa (arRP) in an eight member consanguineous pedigree of European ancestry. Additionally, one patient exhibited developmental abnormalities including patent ductus arteriosus and chorioretinal and iris colobomas. The second patient developed acne from young age and extending into the 5th decade. Both patients had undetectable levels of RBP4 in the serum suggesting that this mutation led to either mRNA or protein instability resulting in a null phenotype. In addition, the patients exhibited severe vitamin A deficiency, and diminished serum retinol levels. Circulating transthyretin levels were normal. This study identifies the RBP4 splice site change as the cause of RP in this pedigree. The presence of developmental abnormalities and severe acne in patients with retinal degeneration may indicate the involvement of genes that regulate vitamin A absorption, transport and metabolism.
Sam68 (Src-associated protein in mitosis 68 kDa) is a multifunctional protein, known to govern cellular signal transduction, transcription, RNA metabolism, proliferation, apoptosis and HIV-1 replication. Although intrinsic mechanisms that modulate Sam68 function are beginning to emerge, the regulatory events contributing to its expression remain elusive. We previously reported that heat shock protein-22 (Hsp22) antagonizes Sam68 function in rev-response element (RRE)-mediated gene expression. We now demonstrate that Sam68 levels correlate inversely with Hsp22 in a variety of cells, including U87, Jurkat, 293T and U-937. In U87 glioblastoma cells, which contained high levels of Hsp22 than other cell lines tested, Hsp22 knockdown dramatically increased both Sam68 mRNA and protein, altered cellular morphology and enhanced cell proliferation. This heightened proliferation was associated with a sharp decrease in G0/G1 and a corresponding increase in S and G2/M phases in exponentially growing cultures. The increased S phase population in turn correlated with enhanced expression of cell cycle regulatory proteins such as cyclin E, cyclin A, ribonucleotide reductase (RNR) and proliferating cell nuclear antigen (PCNA), which are required for the transition of cells from G1 to S phase. Collectively, our results demonstrate for the first time that Hsp22 regulates Sam68 expression and the ratio of Sam68 to Hsp22 may determine the proliferative potential of glioblastoma cells.
Hsp22 knockdown; Sam68; Cell morphology; Proliferation; Cell cycle analysis
Stem cell maintenance is essential for growth and development of plants and animals. Similar to animal studies, transcription factors play a critical role in plant stem cell maintenance, however the regulatory logic is not well understood. Shoot apical meristems (SAMs) harbor a pool of pluoripotent stem cells and they provide cells for the development of all above-ground organs. Molecular genetic studies spanning more than a decade have revealed cell-cell communication logic underlying stem cell homeostasis. WUSCHEL (WUS), a homeodomain transcription factor expressed in cells of the organizing center specifies stem cells in overlying cells of the central zone (CZ) and also activates a negative regulator-CLAVATA3 (CLV3). CLV3, a small secreted peptide, binds to CLAVATA1 (CLV1) and also possibly to CLV1-related receptors to activate signaling which restricts WUS transcription. Though the CLV-WUS feedback network explains the cell-cell communication logic of stem cell maintenance, how WUS communicates with adjacent cells had remained elusive. In October 15 2011 issue of Genes and Development, we report that WUS protein synthesized in cells of organizing center migrates into adjacent cells via cell-cell movement and activates CLV3 transcription by directly binding to promoter elements.
shoot apical meristem; CLAVATA3; CLAVATA1; central zone and peripheral zone
The acquisition of drug-resistance mutations by infectious pathogens remains a pressing health concern, and the development of strategies to combat this threat is a priority. Here we have applied a general strategy, inverse design using the substrate envelope, to develop inhibitors of HIV-1 protease. Structure-based computation was used to design inhibitors predicted to stay within a consensus substrate volume in the binding site. Two rounds of design, synthesis, experimental testing, and structural analysis were carried out, resulting in a total of 51 compounds. Improvements in design methodology led to a roughly 1000-fold affinity enhancement to a wild-type protease for the best binders, from Ki of 30–50 nM in round one to below 100 pM in round two. Crystal structures of a subset of complexes revealed a binding mode similar to each design that respected the substrate envelope in nearly all cases. All four best binders from round one exhibited broad specificity against a clinically relevant panel of drug-resistant HIV-1 protease variants, losing no more than 6–13 fold affinity relative to wild type. Testing a subset of second-round compounds against the panel of resistant variants revealed three classes of inhibitors — robust binders (maximum affinity loss of 14–16 fold), moderate binders (35–80 fold), and susceptible binders (greater than 100 fold). Although for especially high-affinity inhibitors additional factors may also be important, overall, these results suggest that designing inhibitors using the substrate envelope may be a useful strategy in the development of therapeutics with low susceptibility to resistance.
computational drug design; protease inhibitors; drug resistance; substrate envelope hypothesis; binding specificity; inverse design
Gingival fibromatosis is a benign oral condition characterized by enlargement of gingival tissues. It usually develops as an isolated disorder but can be one of the features of a syndrome. This case report is of a 5-year-old male with severe gingival hyperplasia and mild mental retardation which was complicated by open bite, abnormal occlusion, open lip posture, and disabilities associated with mastication and speech. Full mouth gingivectomy in single sitting under general anesthesia was done with electrocautery.
Electrocautery; idiopathic gingival fibromatosis; mental retardation; SOS-1 gene
The aim was to evaluate the quantitative changes in nuclear diameter (ND), cytoplasmic diameter (CD) and nuclear/cytoplasmic ratio (N/C) in cytological buccal smears of iron deficiency anemic patients by comparing with normal healthy individuals.
Materials and Methods:
The study group consisted of 40 healthy individuals and 40 iron deficiency anemic patients who were selected on clinical history, hematological investigations, and confirmed by serum ferritin levels. Exfoliative buccal smears stained with PAP stain were evaluated for cytoplasimic, nuclear diameters, and nuclear/cytoplasmic ratios (N/C) using Image Proexpress Version 6.0 image analysis system. All the parameters were statistically analyzed by using unpaired ‘t’ test.
A significant increase is seen in the average nuclear diameter (ND) and N/C ratio of the anemic group when compared to the control group. The average cytoplasmic diameter (CD) did not show any statistical difference among the two groups.
Oral exfoliative cytological techniques could possibly be a noninvasive alternative diagnostic tool for iron deficiency anemia.
Cytomorphometry; iron deficiency anemia; oral exfoliative cytology
Cutaneous disorders can precede or follow the initiation of hemodialysis treatment. We evaluated the prevalence of various dermatological manifestations in patients undergoing hemodialysis at least twice a week for minimum of three months at our center. Patients were excluded if they were undergoing hemodialysis less than twice a week or on hemodialysis secondary to ESRD following graft dysfunction. One hundred and forty-three patients were evaluated. Among them, there were 113 male and 30 females. Among the skin changes, pruritus accounted for 56%, Xerosis was observed in 52%, Diffuse blackish hyper pigmentation was seen in 40%. Skin infections was seen in 53% of patients, of these fungal, bacterial and viral infections were 27.2%, 14.6%, and 11.2%, respectively. Kyrle's disease was observed only in 6.9%. Other skin manifestations include eczema 4.8%, psoriasis 2.7%, and drug rash 2.1%. Nail changes were observed in 46 patients of whom 27 patients had onychomycosis. Other changes include discoloration, onycholysis, and splinter hemorrhages. Hair changes were observed in 21.7%. Mucosal changes were seen in 27.3%. In our study, pruritus, xerosis, and pigmentation were higher among skin changes. Recognition and management of some of these dermatological manifestations vastly reduce the morbidity and improve the quality of life.
Although inactivation of the androgen receptor (AR) by androgen-ablation or anti-androgen treatment has been frontline therapy for disseminated prostate cancer for over 60 years, it is not curative because castration-resistant prostate cancer cells retain AR activity. Therefore, curative strategy should include targeted elimination of AR protein. Since AR binds to calmodulin (CaM), and since CaM-binding proteins are targets of calpain-mediated proteolysis, we studied the role of CaM and calpain in AR breakdown in prostate cancer cells. Whereas the treatment of prostate cancer cells individually with anti-CaM drug or calcimycin, which increases intracellular Ca++ and activates calpain, led to minimal AR breakdown, combined treatment led to a precipitous decrease in AR protein levels. This decrease in AR protein occurred without noticeable changes in AR mRNA levels, suggesting an increase in AR protein turnover rather than inhibition of AR mRNA expression. Thus, CaM inactivation seems to sensitize AR to calpain-mediated breakdown in prostate cancer cells. Consistent with this possibility, purified recombinant human AR (rhAR) underwent proteolysis in the presence of purified calpain, and the addition of purified CaM to the incubation blocked rhAR proteolysis. Together, these observations demonstrate that AR is a calpain target and AR-bound CaM plays an important role in protecting AR from calpain-mediated breakdown in prostate cancer cells. These observations raise an intriguing possibility that anti-CaM drugs in combination with calpain-activating agents may offer a curative strategy for the treatment of prostate cancer, which relies on AR for growth and survival.
Androgen receptor; calmodulin; calpain; hormone-refractory prostate cancer
Short-chain acyl-CoA dehydrogenase (ACAD) deficiency is an extremely rare inherited mitochondrial disorder of fat metabolism. This belongs to a group of diseases known as fatty acid oxidation disorders. Screening programmes have provided evidence that all the fatty acid oxidation disorders combined are among the most common inborn errors of metabolism. Mitochondrial beta oxidation of fatty acids is an essential energy producing pathway. It is a particularly important pathway during prolonged periods of starvation and during periods of reduced caloric intake due to gastrointestinal illness or increased energy expenditure during febrile illness. The most common presentation is an acute episode of life threatening coma and hypoglycemia induced by a period of fasting due to defective hepatic ketogenesis. Here, the case of a 4 month old female patient who had seizures since the third day of her birth and persistent hypoglycemia is described. She was born to parents of second degree consanguinity after 10 years of infertility treatment. There was history of delayed cry after birth. Metabolic screening for TSH, galactosemia, 17-OHP, G6PD, cystic fibrosis, biotinidase were normal. Tandem mass spectrometric (TMS) screening for blood amino acids, organic acids, fatty acids showed elevated butyryl carnitine (C4) as 3.40 μmol/L (normal <2.00 μmol/L), hexanoyl carnitine (C6) as 0.92 μmol/L (normal <0.72 μmol/L), C4/C3 as 2.93 μmol/L (normal <1.18 μmol/L). The child was started immediately on carnitor syrup (carnitine) 1/2 ml twice daily. Limitation of fasting stress and dietary fat was advised. Baby responded well by gaining weight and seizures were controlled. Until now, less than 25 patients have been reported worldwide. The limited number of patients diagnosed until now is due to the rarity of the disorder resulting in under diagnosis.
Short chain acyl-CoA dehydrogenase (SCAD); Tandem mass spectrometry (TMS); Gas
chromatography; Liquid chromatography; Ethylmalonic acid; Butryl-carnitine
We examined the metabolism of two synthetic analogs of 1α,25-dihydroxyvitamin D3 (1), namely 1α,25-dihydroxy-16-ene-23-yne-vitamin D3 (2) and 1α,25-dihydroxy-16-ene-23-yne-26,27-dimethyl-vitamin D3 (4) using rat cytochrome P450 24A1 (CYP24A1) in a reconstituted system. We noted that 2 is metabolized into a single metabolite identified as C26-hydroxy-2 while 4 is metabolized into two metabolites, identified as C26-hydroxy-4 and C26a-hydroxy-4. The structural modification of adding methyl groups to the side chain of 1 as in 4 is also featured in another analog, 1α,25-dihydroxy-22,24-diene-24,26,27-trihomo-vitamin D3 (6). In a previous study, 6 was shown to be metabolized exactly like 4, however, the enzyme responsible for its metabolism was found to be not CYP24A1. To gain a better insight into the structural determinants for substrate recognition of different analogs, we performed an in silico docking analysis using the crystal structure of rat CYP24A1 that had been solved for the substrate-free open form. Whereas analogs 2 and 4 docked similar to 1, 6 showed altered interactions for both the A-ring and side chain, despite prototypical recognition of the CD-ring. These findings hint that CYP24A1 metabolizes selectively different analogs of 1, based on their ability to generate discrete recognition cues required to close the enzyme and trigger the catalytic mechanism.
1α,25-Dihydroxyvitamin D3; 1α,25-Dihydroxy-16-ene-23-yne-vitamin; D3; EB1089; Cytochrome P450 24A1; Molecular docking; Vitamin D metabolism
The identification of a blood-based diagnostic marker is a goal in many areas of medicine, including the early diagnosis of prostate cancer. We describe the use of averaged differential display as an efficient mechanism for biomarker discovery in whole blood RNA. The process of averaging reduces the problem of clinical heterogeneity while simultaneously minimizing sample handling.
RNA was isolated from the blood of prostate cancer patients and healthy controls. Samples were pooled and subjected to the averaged differential display process. Transcripts present at different levels between patients and controls were purified and sequenced for identification. Transcript levels in the blood of prostate cancer patients and controls were verified by quantitative RT-PCR. Means were compared using a t-test and a receiver-operating curve was generated. The Ring finger protein 19A (RNF19A) transcript was identified as having higher levels in prostate cancer patients compared to healthy men through the averaged differential display process. Quantitative RT-PCR analysis confirmed a more than 2-fold higher level of RNF19A mRNA levels in the blood of patients with prostate cancer than in healthy controls (p = 0.0066). The accuracy of distinguishing cancer patients from healthy men using RNF19A mRNA levels in blood as determined by the area under the receiving operator curve was 0.727.
Averaged differential display offers a simplified approach for the comprehensive screening of body fluids, such as blood, to identify biomarkers in patients with prostate cancer. Furthermore, this proof-of-concept study warrants further analysis of RNF19A as a clinically relevant biomarker for prostate cancer detection.
A variety of polymer nanoparticles (NP) are under development for imaging and therapeutic use. However, little is known about their behavior. This study examined pharmacokinetics, distribution and elimination of stable polyacrylamide (PAA) nanoparticles (~31 nm average diameter). PAA-NPs and polyethylene glycol-coated PAA-NPs were injected into the tail veins of healthy male rats. Blood, tissues and excreta were collected at times ranging from 5 minutes to 120 hours and their radioactive content was quantified. A mathematical model was then applied to analyze the distribution dynamics of both NPs. Elimination from the blood could be accounted for by a quick but finite relocation to the major organs (about 20%, 0.6 to 1.3h half-lives), and a slower distribution to the carcass (about 70%, 35 to 43h half-lives). Excreted urinary levels correlated with blood concentrations. Combined cumulative urinary and fecal output accounted for less than 6% of the dose at 120h. Compared to five other polymeric nanoparticles, the studied particles are at the highest half-lives and Area Under the Curve (4000 to 5000 %-h). These two parameters decrease by three orders of magnitude when nanoparticle size increases from the 30 nm range up to 250 nm. For similar sizes, pegylated nanoparticles are more persistent in the blood than non pegylated ones, but this difference is much smaller in the 30 nm and relatively high dose range than above 100 nm. Persistence of PAA NPs is not associated with acute toxicity signs as measured by typical serum markers of inflammation and cellular damage.
Nanoparticle; polyacrylamide; pharmacokinetics; nanomedicine; biodistribution
To assess pharmacokinetic interaction of garlic with atorvastatin in dyslipidemic rats.
Materials and Methods:
Sprague Dawley rats with induced dyslipidemia were divided into five groups of eight rats each. Group 1 was given atorvastatin (10 mg/kg body weight (b.wt) orally), group 2 was given atorvastatin (10 mg/kg b.wt orally)+garlic (1% w/w in feed), group 3 was maintained on atorvastatin (5 mg/kg b.wt orally)+garlic (0.5% w/w in feed), group 4 was maintained on atorvastatin (7.5 mg/kg b.wt orally)+garlic (0.25% w/w in feed), and group 5 was maintained on atorvastatin (2.5 mg/kg b.wt orally)+garlic (0.75% w/w in feed) for 12 weeks. Blood samples were collected at predetermined time intervals for kinetic analysis after the first and last oral dosing of atorvastatin for single and multiple dose studies, respectively. Plasma samples were assayed for atorvastatin concentration by High-Performance Liquid Chromatography (HPLC) and then the concentration-time data were analyzed.
Maximum observed plasma concentration (Cmax), half-life, Area Under Plasma Concentration Time Curve (AUC), and Mean Resident Time (MRT) were significantly (P<0.05) increased during multiple dose kinetic study and elimination rate constant was significantly (P<0.05) decreased in comparison with their respective single-dose values, while there was no significant difference in time to achieve maximum concentration (tmax) in all groups during both phases of the study. The highest values for kinetic parameters were observed in group 2 with correspondingly low activity of Cytochrome P450 (CYP450).
The study revealed higher values [Cmax, AUC, Area Under The Moment Curve (AUMC), MRT, and half-life] of atorvastatin in garlic-treated groups.
Atorvastatin; garlic; pharmacokinetics
Cherubism is a rare non-neoplastic hereditary disease related to genetic mutations characterized by symmetrically swollen cheeks, particularly over the angles of the mandible, and an upward turning of the eyes. The affected mandible and maxilla begin to swell in early childhood, and gradually increase until the age of puberty. Apparently, surgical intervention is unnecessary unless significant functional, esthetic, or emotional disturbances develop. In the present paper, we report a case of cherubism, with classic features that was classified as grade 3, managed with surgery and followed up for 2-years after treatment.
Cherubism; hereditary multilocular cystic lesion; non-neoplastic lesion
primary infertility; premature ovarian failure; terminal Xq deletion
A series of new HIV-1 protease inhibitors with the hydroxyethylamine core and different phenyloxazolidinone P2 ligands were designed and synthesized. Variation of phenyl substitutions at the P2 and P2′ moieties significantly affected the inhibitors’ binding affinity and antiviral potency. In general, compounds with 2- and 4-substituted phenyloxazolidinones at P2 exhibited lower binding affinities than 3-substituted analogues. Crystal structure analyses of ligand-enzyme complexes revealed different binding modes for 2- and 3-substituted P2 moieties in the protease S2 binding pocket, which may explain the compounds’ different binding affinities. Several compounds with 3-substituted P2 moieties demonstrated pM binding affinity, low nM antiviral potency against patient-derived viruses from HIV-1 clades A, B and C, and most retained potency against drug-resistant viruses. Further optimization of these compounds using structure-based design may lead to the development of novel protease inhibitors with improved activity against drug-resistant strains of HIV-1.
Shoot apical meristem (SAM) stem cell niche is an interconnected network of distinct cell types; the central zone (CZ) harbors a small pool of stem cells, the stem cell progeny are displaced into the adjacent peripheral zone (PZ) and the rib zone (RZ) located beneath the CZ where they differentiate. Relative ratios of cell types remain constant. Genetic studies have shown that the levels or spatial confinement of WUS, a homeodomain transcription factor to few cells in the RZ, is critical for regulating stem cell number. However, static analyses of terminal mutant phenotypes have not revealed WUS-mediated mechanisms of stem cell homeostasis. In a recent study we have employed transient manipulation of WUS levels and live imaging to show that it controls several interdependent processes, such as regulation of stem cell number, cell division rates of stem cell progenitors and their patterns of differentiation, thus providing robustness to the process.
shoot apical meristem; CLAVATA3; CLAVATA1; central zone; peripheral zone
Production of lignolytic enzymes by the mushroom fungus Stereum ostrea in liquid medium under conditions of vegetative growth was examined for 10 days in comparison to the reference culture Phanerochaete chrysosporium. Though growth and secretion of extracellular protein by S. ostrea were comparable to those of P. chrysosporium, yields of laccase enzyme by S. ostrea were higher than laccase titres of P. chrysosporium by more than 2 folds on the peak production time interval (IVth day of incubation). S. ostrea yielded titres of 25 units of laccase/ml as against 8.9 units of laccase/ml on the IVth day of incubation. Stereum ostrea also exhibited activities of other lignolytic enzymes, lignin peroxidase (LiP) and manganese peroxidase (MnP), higher than the reference culture. Growth of S. ostrea on the medium in the presence of Remazol orange 16 resulted in the decolourisation of dye, confirming the presence of lignolytic enzymes. S. ostrea appears to be a promising culture with complete lignolytic system.
Periapical surgery needs asepsis, a bloodless field for ensuring success of the treatment. Efficacy of Povidone Iodine (PVI) in the elimination of pathogen causing periapical lesions is well established. PVI is also widely used as a disinfectant, sclerosing agent, styptic as well as an anti-odematous agent.
Materials and Methods:
This prospective pilot study done on 20 males between 20-40 years age group with periapical lesions in single rooted maxillary anterior tooth of 1-2 cm in diameter. The bleeding time, clotting time, bleeding time at the apex, drugs used and visual analogue scale of oedema on postoperative days were obtained. Descriptive statistics, paired t test and independent t-test were used.
Results and Conclusion:
Results show a statistically significant reduction in the time required to achieve a bloodless field and a marked decrease in oedema in the first and second postoperative days resulting in lesser consumption of NSAIDs. In conclusion, the effect of PVI in periapical surgery seems to reduce the bleeding time at apex, total dose of NSAIDs used, oedema on first two postoperative days with high statistical significance. Hence the routine use of saline in periapical surgeries may be effectively substituted with PVI. The finding of this pilot study has to be evaluated using wider samples for effective clinical translations.
Apicoectomy; periapical surgery; periradicular surgery; povidone iodine