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Background and Aim: The aim of the study was to compare the physical (processing shrinkage) and mechanical properties (bending deflection, flexure strength, and flexure modulus) of pressure-molded (Lucitone 199 and ProBase Hot) and injection-molded (SR-Ivocap) denture base materials in different conditions. Materials and Methods: Two denture base materials for pressure molding, Lucitone 199 and ProBase Hot, and one for injection molding (SR-Ivocap) were tested. Polymerization shrinkage (PS) was determined by measuring the linear distances between the reference points on the wax patterns (65 mm × 55 mm × 6 mm) and the corresponding cured acrylic plates and calculating the difference. Rectangular specimens (50 mm × 10 mm × 2.5 mm) were machined from these acrylic plates and used to measure bending deflection (BD) at various load levels, flexure strength (FS), and modulus of elasticity using a three-point bend test on an Instron Universal Testing Machine. A minimum of seven specimens were tested for each variable category. For each material, the percentage of specimens that failed within the load range of 9-10 kg was noted. Statistical analysis involved calculation of mean and standard deviations followed by group comparison of properties of different materials by using analysis of variance (ANOVA) and Tukey′s multiple range tests. Level of significance was set at P < 0.05. Result: There was no significant difference between the PS values. ProBase Hot exhibited significantly less BD and greater FS values than the other two materials (P < 0.05). Within the load range of 9-10 kg., 5% of the lucitone specimens, 25% of the SR-Ivocap specimens, and all of the ProBase Hot specimens fractured. Conclusion: The three tested denture base acrylics did not show any significant differences in processing shrinkage. However, ProBase Hot showed significantly lower bending deflection values than Lucitone 199 and SR-Ivocap. Compared to Lucitone 199 and SR-Ivocap, ProBase Hot is a tougher and a stiffer material. Hence, it is more likely to fracture readily if subjected to extreme loading conditions due to the accidental fall of the denture on a hard surface or if the denture wearer inadvertently bites on a particularly hard particle.

Mucormycosis is a serious infection caused by a opportunistic fungi. The most frequently affected are is the maxillofacial region. A case of mucormycosis of the palatal tissue in a female diabetic patient is reported.

Charcoal rot is a post-flowering stalk rot (PFSR) disease of maize caused by the fungal pathogen, Macrophomina phaseolina. It is a serious concern for smallholder maize cultivation, due to significant yield loss and plant lodging at harvest, and this disease is expected to surge with climate change effects like drought and high soil temperature. For identification and validation of genomic variants associated with charcoal rot resistance, a genome-wide association study (GWAS) was conducted on CIMMYT Asia association mapping panel comprising 396 tropical-adapted lines, especially to Asian environments. The panel was phenotyped for disease severity across two locations with high disease prevalence in India. A subset of 296,497 high-quality SNPs filtered from genotyping by sequencing was correcting for population structure and kinship matrices for single locus mixed linear model (MLM) of GWAS analysis. A total of 19 SNPs were identified to be associated with charcoal rot resistance with P-value ranging from 5.88 × 10−06 to 4.80 × 10−05. Haplotype regression analysis identified 21 significant haplotypes for the trait with Bonferroni corrected P ≤ 0.05. For validating the associated variants and identifying novel QTLs, QTL mapping was conducted using two F2:3 populations. Two QTLs with overlapping physical intervals, qMSR6 and qFMSR6 on chromosome 6, identified from two different mapping populations and contributed by two different resistant parents, were co-located with the SNPs and haplotypes identified at 103.51 Mb on chromosome 6. Similarly, several SNPs/haplotypes identified on chromosomes 3, 6 and 8 were also found to be physically co-located within QTL intervals detected in one of the two mapping populations. The study also noted that several SNPs/haplotypes for resistance to charcoal rot were located within physical intervals of previously reported QTLs for Gibberella stalk rot resistance, which opens up a new possibility for common disease resistance mechanisms for multiple stalk rots.

Aims: To measure the outcome of preoperative subconjunctival mitomycin C 1 month before bare sclera and conjunctival autografting using fibrin glue in terms of recurrence rate and complications. Settings and Design: This was a prospective, randomized, interventional, hospital-based comparative study. Materials and Methods: Sixty eyes of 58 consecutive patients with primary, progressive pterygium were randomly allocated into two equal Groups (A and B) of 30 each. In Group A, subconjunctival injection of mitomycin C (MMC) (0.1 ml of 0.1 mg/ml) 1 month before bare sclera technique and in Group B pterygium excision with conjunctival autografting using fibrin glue were performed. The study period was from December 2010 to October 2012, and patients were followed up for 18 months. The outcome measures were significant corneoscleral complications and recurrence. Results: The mean age of patients in the study was 38.6 ± 12.6 years with females slightly outnumbering males. Majority (58.6%) of patients were pursuing outdoor occupations. The mean follow-up period of MMC group was 10.2 ± 4.49 months, whereas that of conjunctival autograft with glue group was 10.8 ± 3.66 months. The average surgery time was more for conjunctival autografting with fibrin glue than subconjunctival mitomycin before bare sclera. One (3.33%) patient in the MMC group and 2 (6.67%) patients in the fibrin glue group had recurrence within the study period. Both the surgical techniques were not found to be associated with any serious vision-threatening complications. Conclusions: Subconjunctival MMC 1 month before bare sclera is simple, safe, economical, less time-consuming, technically less demanding, and as effective as conjunctival autografting with fibrin glue fixation.

The title compound, 4, 4′-methoxy bis-hydrazone, C 16 H 16 N 2 O 2 , has been characterized thus: monoclinic, Cc , a=17.418(3) Å, b=10.710(3) Å, c=8.435(3) Å, β=113.74(.02)°, V=1440.3(7) Å 3 , Z =4, F.W.=268.31, D c =1.237 Mg.m −3 , F 000 =568.00, λ( Mo K α )=0.71069 Å, μ=0.083 mm −1 , final R 1 and w R2 are 0.0427 and 0.1413, respectively. The compound is a mesogen which exhibits nematic phase and also shows super cooling. [ABSTRACT FROM PUBLISHER]

Objective: To determine the denture cleanliness and denture hygiene habits in complete denture wearers in Nizamabad′s population. Materials and Methods: In this study, a self-administered structured questionnaire was developed to know the attitude of the patients from the Department of Prosthodontics regarding denture hygiene. The study sample consisted of a total of 200 subjects, which included 110 (55%) males and 90 (45%) females. Results: Nearly half of the subjects cleaned their dentures daily (70%). Participants from the younger age group and who had been wearing dentures from 0 years to 5 years maintained a better frequency of cleaning. The majority of these subjects used brush and toothpaste for denture cleansing. After seeing the condition, approximately half of the dentures were rated as dirty (48%). Around 41% of patients were not satisfied with their cleansing methods and 78.5% of the patients claimed that their dentists did not inform them about how to clean their dentures. Older dentures tended to be dirtier than the newer ones (P = 0.0001) and had a higher incidence rate of accompanying denture stomatitis (P = .0001). Conclusion: The poor condition of complete dentures seen in the population was mainly due to irregular cleansing habits and also less usage of cleansing solutions. Dentists should give proper instructions regarding the maintenance of denture hygiene.

Introduction: Targeted diagnosis of specific human cancer types continues to be of significant interest in nuclear medicine. 99mTc is ideally suited as a diagnostic radiometal for in vivo tumor targeting due to its ideal physical characteristics and diverse labeling chemistries in numerous oxidation states., Methods: In this study, we report a synthetic approach toward design of a new tridentate amine ligand for the organometallic aqua-ion [99mTc(H2O)3(CO)3]+. The new chelating ligand framework, 2-(N,N'-Bis(tert-butoxycarbonyl)diethylenetriamine) acetic acid (DTMA), was synthesized from a diethylenetriamine precursor and fully characterized by mass spectrometry and nuclear magnetic resonance spectroscopy (1H and 13C). DTMA was conjugated to H2N-(X)-BBN(7-14)NH2, where X=an amino acid or aliphatic pharmacokinetic modifier and BBN=bombesin peptide, by means of solid phase peptide synthesis. DTMA-(X)-BBN(7-14)NH2 conjugates were purified by reversed-phase high-performance chromatography and characterized by electrospray-ionization mass spectrometry., Results: The new conjugates were radiolabeled with [99mTc(H2O)3(CO)3]+ produced via Isolink radiolabeling kits to produce [99mTc(CO)3-DTMA-(X)-BBN(7-14)NH2]. Radiolabeled conjugates were purified by reversed-phase high-performance chromatography. Effective receptor binding behavior was evaluated in vitro and in vivo., Conclusions: [99mTc(CO)3-DTMA-(X)-BBN(7-14)NH2] conjugates displayed very high affinity for the gastrin releasing peptide receptor in vitro and in vivo. Therefore, these conjugates hold some propensity to be investigated as molecular imaging agents that specifically target human cancers uniquely expressing the gastrin releasing peptide receptor subtypes.

Bombesin (BBN) peptide exhibits high selectivity and affinity for the gastrin-releasing peptide receptor (GRPr). The GRPr is overexpressed on many human cancer cell types, thus making BBN a potent delivery vehicle for radionuclide targeting. In this study, the biologically active minimal sequence BBN(7-14) was labeled using the novel Tc '4 + 1' mixed-ligand system, [Tc(NS3)(CN-R)], in which Tc(III) is coordinated by a monodentate isocyanide linker bearing the peptide and the tetradentate, tripodal chelator, 2,2',2''-nitrilotriethanethiol (NS3). BBN(7-14) was N-terminally modified with Gly-Gly-Gly, betaAla, and Ser-Ser-Ser spacer groups (X) and functionalized with 4-(isocyanomethyl)benzoic acid (L1) or 4-isocyanobutanoic acid (L2), resulting in a series of [M(NS3)(L-X-BBN(7-14))] conjugates (M = 99mTc, Re). The isocyanide ligand frameworks were introduced using novel bifunctional coupling agents. The spacer groups (X), the monodentate isocyanide units, and a tetradentate NS3 chelator bearing a pendant carboxylic acid (NS3COOH) were proposed as pharmacological modifiers. 99mTc-labeling was performed in a two-step procedure by first preparing 99mTc-EDTA/mannitol followed by reactions with the isocyanides and NS3 or NS3COOH ligand frameworks. The 99mTc complexes were obtained with a radiochemical yield of 30-80% depending on the amount of the isocyanide (20-100 nmol) used. These new conjugates were purified by reversed-phased high-performance liquid chromatography (RP-HPLC) to give a radiochemical purity of >or=95%. The 99mTc conjugates exhibited high in vitro stability (>90%, 24 h). Analogous nonradioactive Re conjugates were synthesized and characterized by electrospray ionization mass spectrometry (ESI-MS). RP-HPLC analyses of the Re conjugates indicated that they exhibited identical retention times to the corresponding 99mTc conjugates under identical HPLC conditions, demonstrating structural similarity between the two metalated species. The [Re(NS3)(L-X-BBN(7-14))] conjugates exhibited GRPr affinity in the nanomolar range as demonstrated by in vitro competitive binding assays using PC-3 human prostate cancer cells. In vitro internalization/externalization assays indicated that approximately 65% of [99mTc(NS3)(L2-betaAla-BBN(7-14))] conjugate was either surface-bound or internalized in PC-3 cells. Cell-associated activity for all other 99mTc conjugates was below 20%. Biodistribution studies of [99mTc(NS3)(L-betaAla-BBN(7-14))], L = L1 or L2, in normal, CF-1 mice showed minimal accumulation in normal pancreas (a tissue expressing the GRPr in high density in rodent models) and rapid hepatobiliary elimination. Introduction of a carboxyl group onto the NS3 ligand framework had only minimal effects to increase renal excretion. Activity distribution and accumulation was highly dominated by the relatively lipophilic '4 + 1' complex unit.

Gastrin-releasing peptide (GRP) receptors are overexpressed on several types of human cancer cells, including breast, prostate, small cell lung, and pancreatic cancers. Bombesin (BBN), a 14-amino acid peptide that is an analogue of human GRP, binds to GRP receptors with very high affinity and specificity. The aim of this study was to develop a new fluorescent probe based on BBN having high tumor uptake and optimal pharmacokinetics for specific targeting and optical imaging of human breast cancer tissue. In this study, solid-phase peptide synthesis was used to produce H(2)N-glycylglycylglycine-BBN[7-14]NH(2) peptide with the following general sequence: H(2)N-G-G-G-Q-W-A-V-G-H-L-M-(NH(2)). This conjugate was purified by reversed-phase high-performance liquid chromatography and characterized by electrospray-ionization mass spectra. The fluorescent probe Alexa Fluor 680-G-G-G-BBN[7-14]NH(2) conjugate was prepared by reaction of Alexa Fluor 680 succinimidyl ester to H(2)N-G-G-G-BBN[7-14]NH(2) in dimethylformamide (DMF). In vitro competitive binding assays, using (125)I-Tyr(4)-BBN as the radiolabeling gold standard, demonstrated an inhibitory concentration 50% value of 7.7 +/- 1.4 nM in human T-47D breast cancer cells. Confocal fluorescence microscopy images of Alexa Fluor 680-G-G-G-BBN[7-14]NH(2) in human T-47D breast cancer cells indicated specific uptake, internalization, and receptor blocking of the fluorescent bioprobe in vitro. In vivo investigations in SCID mice bearing xenografted T-47D breast cancer lesions demonstrated the ability of this new conjugate to specifically target tumor tissue with high selectivity and affinity.

We have described the synthesis of tridentate pyrazolyl ligand frameworks for coordination to the fac-[*M(CO)(3)](+) metal fragment (*M=(186/188)Re or (99m)Tc). These ligands impart a degree of kinetic inertness on the metal center, warranting their study in biological systems. We herein report in vitro/in vivo radiolabeling investigations of a new series of pyrazolyl bombesin (BBN) conjugates radiolabeled via the Isolink kit. These new conjugates are based on the general structure [(99m)Tc-pyrazolyl-X-BBN[7-14]NH(2)], where X=beta-alanine, serylserylserine or glycylglycylglycine. The pyrazolyl ligand is a tridentate ligand framework that coordinates the metal center through nitrogen donor atoms. The results of these investigations demonstrate the ability of these new conjugates to specifically target the gastrin-releasing peptide receptor subtype 2, which is overexpressed on human prostate PC-3 cancerous tissues. Therefore, these studies suggest the tridentate pyrazolyl ligand framework to be an ideal candidate for the design and development of low-valent (99m)Tc-based diagnostic radiopharmaceuticals based on BBN or other targeting vectors.

Radiolabeled, receptor-specific peptides are becoming increasingly popular as targeting vectors for the design and development of new diagnostic and therapeutic radiopharmaceuticals. The over-expression of functioning receptors on a variety of human cancers makes this method of drug development a viable tool for tumor targeting in vivo. This review describes some of the more recent efforts that are currently underway towards development of new receptor-specific radiopharmaceuticals. Diagnostic/therapeutic radionuclides, specific metal co-ordinating ligands/chelating systems, spacer technology, radiolabeling protocols, and specific peptides/peptide conjugates will be discussed in detail.