An in-vitro quantitative investigation on the synergistic effect of capsaicin and 5-fluorouracil encapsulated into lipid nanocapsules to treat breast cancer.

BACKGROUND: Breast cancer conventional therapeutics are effective; however, they encounter some limitations including multidrug resistance, the presence of pharmacological barriers, and non-selectivity which hinder their optimal therapeutic efficacy. AIM: Overcoming such drawbacks necessitates the development of efficient drug vehicles including lipid-based nanoparticles. This study aimed to quantitatively investigate in-vitro the synergistic therapeutic effect of the novel combination of capsaicin and 5-fluorouracil (5-FU) encapsulated in lipid nanocapsules (LNCs). METHOD: To this end, thorough physicochemical and in-vitro assessments on the breast cancer cell line (MCF-7) were done. The drug-loaded LNCs were characterized using DLS, TEM imaging, stability study, and in-vitro release study. Furthermore, the biological activity of the prepared LNCs was assessed by implementing comparative cytotoxicity studies as well as apoptosis, and cell cycle flow cytometric analyses. RESULTS: The developed nanoformulations were monodisperse with average particle size (PS) of 31, 43.8, and 127.3 nm for empty LNCs, Cap-LNCs, and 5-FU-LNCs, respectively, and with a surface charge of -35.4, -21.7 and -31.4 mV, respectively, reflecting good physical stability. The TEM micrographs revealed the spherical morphology of the drugs-loaded LNCs with comparable PS to that obtained by DLS. on the other hand, all the biological assessments confirmed the superior antiproliferative effect of the combined drug-loaded LNCs over their free drug counterparts. CONCLUSION: Intriguingly, the study findings highlighted the potential synergistic activity of the drugs (capsaicin and 5-FU) and the extensive enhancement of their biological activity through incorporation into LNCs. Such promising results will pave the way to further novel combined nanoformulation in preclinical and clinical studies on breast cancer patients.

Defatted Seed Residue of Cucumis Melo as a Novel, Renewable and Green Biosorbent for Removal of Selected Heavy Metals from Wastewater: Kinetic and Isothermal Study.

The present work was aimed at studying the biosorption of two important heavy metals, viz. Pb and Cr, using defatted seed residue of Cucumis melo as biosorbent. As this study for the biosorption of the selected biosorbent is being carried out for the first time, optimization of the% sorption was carried out with the help of Taguchi method. Three most influential experimental factors were taken into account for this purpose, including the amount of sorbent, amount of sorbate and shaking time. For Pb, maximum% sorption was found to be 94.1%, using 2 g of sorbent and 5 ppm of sorbate after 2 h of shaking. Similarly, for Cr, maximum% sorption was 92.5% using 2 g of sorbent, 10 ppm of sorbate and 3 h of shaking. For Pb, the highest% contribution, which was determined by ANOVA, was given by the amount of sorbate (54.7%) followed by the amount of sorbent (38.8%) and the least contribution was given by the shaking time (6.47%). Similarly, for Cr, the highest% contribution, which was determined by ANOVA, was given by the amount of sorbate (75%) followed by the amount of sorbent (16%) and the least contribution was given by the shaking time (8.65%). Kinetic and isothermal studies were also performed to understand the nature of adsorption mechanism. For this purpose, linear and non-linear forms of three sorption isotherms were employed including Freundlich, Langmuir and Dubnin-Radushkevich isotherm. From these observations, it can be concluded that the defatted seed residue of Cucumis melo can be regarded as a novel, renewable, green and cost-effective biosorbent for removal of heavy metals from wastewater.

Development of Ion Character Property Relationship (IC-PR) for Removal of 13-Metal Ions by Employing a Novel Green Adsorbent Aerva javanica.

The novel Aerva javanica absorbent was applied for the removal of thirteen selected metal ions from a distilled water solution of each metal by the batch adsorption method. The optimization remediation parameters of the metal ions for the batch adsorption approach were developed, which were the initial concentrations (60 ppm), contact time (60 min) and pH (7). The basic properties of metal ion affected the adsorption results; therefore, 21 properties of metal ions were selected, which are called "descriptors". The most significant descriptors were selected that were vital for the adsorption results, such as covalent index, polarizability and ion charge. The developed model equation by the descriptors provided more than 80% accuracy in the predicted results. Furthermore, Freundlich and Langmuir adsorption models were also applied on the results. Constants of the Freundlich and Langmuir models were also used for model generation, and the results revealed the importance of a covalent index for the removal phenomenon of metal ions. The current study provided a suitable Ion Character Property Relationship (IC-PR) for the removal of metal ions, and future predictions can be achieved on the proposed adsorbent with significant accuracy. The ecofriendly and cost effective Aerva javanica absorbent in the batch experimental model of the current study predicted that this novel absorbent can be used for the removal of a wide spectrum of heavy metal ions from different sources of waste waters.

Efficient Photocatalytic Degradation of Congo Red Dye Using Facilely Synthesized and Characterized MgAl2O4 Nanoparticles.

The discharge of congo red dye into water sources by factories has been associated with a range of health concerns, such as cancer, redness, skin irritation, and allergic reactions. As a result, this research focused on the cost-effective and straightforward production of MgAl2O4 nanoparticles by using the Pechini sol-gel process. Subsequently, these nanoparticles were employed for the successful photocatalytic decomposition of congo red dye. Moreover, extensive characterization of the fabricated MgAl2O4 nanoparticles was conducted through diverse methodologies, which included Fourier-transform infrared spectroscopy, ultraviolet-visible spectrophotometry, high-resolution transmission electron microscopy (HR-TEM), field-emission scanning electron microscopy (FE-SEM), and powder X-ray diffraction (XRD). Furthermore, the XRD analysis disclosed that the average crystal size of the produced MgAl2O4 nanoparticles is 10.36 nm, and their optical energy gap was determined to be 3.71 eV. The FE-SEM examination unveiled a combination of spherical and disorganized structures with a 0.14 µm average grain size. HR-TEM analysis, in turn, revealed that the fabricated MgAl2O4 nanoparticles were composed of minuscule spherical particles with an average diameter of 8.75 nm. The maximum degradation of 50 mL of congo red dye at a concentration of 25 mg/L reached 99.27% within 80 min at a pH of 3. Additionally, the findings confirmed the consistent decomposition activity toward congo red dye even after four cycles, thereby validating the effectiveness and reusability of the MgAl2O4 nanoparticles that were developed in this study.

Synthesis, characterization, biological potency, and molecular docking of Co2+, Ni2+ and Cu2+ complexes of a benzoyl isothiocyanate based ligand.

The primary objective of the present study was to produce metal complexes of H4DAP ligand (N,N'-((pyridine-2,6-diylbis(azanediyl))bis(carbonothioyl))dibenzamide) derived from 2,6-diaminopyridine and benzoyl isothiocyanate with either ML or M2L stoichiometry. There are three distinct coordination complexes obtained with the formulas [Co(H2DAP)]·H2O, [Ni2(H2DAP)Cl2(H2O)2]·H2O, and [Cu(H4DAP)Cl2]·3H2O. The confirmation of the structures of all derivatives was achieved through the utilization of several analytical techniques, including FT-IR, UV-Vis, NMR, GC-MS, PXRD, SEM, TEM analysis, and QM calculations. Aiming to analyze various noncovalent interactions, topological methods such as QTAIM, NCI, ELF, and LOL were performed. Furthermore, the capacity of metal-ligand binding was examined by fluorescence emission spectroscopy. An in vitro investigation showed that the viability of MDA-MB-231 and HepG-2 cells was lower when exposed to the manufactured Cu2+ complex, in comparison to the normal cis-platin medication. The compounds were further evaluated for their in vitro antibacterial activity. The Ni2+ complex has shown promising activity against all tested pathogens, comparable to the reference drugs Gentamycin and Ketoconazole. Furthermore, a computational docking investigation was conducted to further examine the orientation, interaction, and conformation of the recently created compounds on the active site of the Bcl-2 protein.

Facile synthesis and characterization of Fe3O4/analcime nanocomposite for the efficient removal of Cu(II) and Cd(II) ions from aqueous media.

In the water purification field, heavy metal pollution is a problem that causes severe risk aversion. This study aimed to examine the disposal of cadmium and copper ions from aqueous solutions by a novel Fe3O4/analcime nanocomposite. A field emission scanning electron microscope (FE-SEM), Fourier transform infrared spectroscopy (FT-IR), and X-ray diffraction were used to characterize the synthesized products. The FE-SEM images showed that the analcime and Fe3O4 samples consist of polyhedral and quasi-spherical shapes with average diameters of 923.28 and 28.57 nm, respectively. Besides, the Fe3O4/analcime nanocomposite consists of polyhedral and quasi-spherical shapes with average diameters of 1100.00 nm. The greatest uptake capability of the Fe3O4/analcime nanocomposite toward the copper and cadmium ions is 176.68 and 203.67 mg/g, respectively. The pseudo-second-order kinetic model and Langmuir equilibrium isotherm best describe the uptake of copper and cadmium ions using the Fe3O4/analcime nanocomposite. The uptake of copper and cadmium ions using the Fe3O4/analcime nanocomposite is exothermic and chemical in nature.

Layer-by-layer development of chitosan/alginate-based platelet-mimicking nanocapsules for augmenting doxorubicin cytotoxicity against breast cancer.

Breast carcinoma is considered one of the most invasive and life-threatening malignancies in females. Mastectomy, radiation therapy, hormone therapy and chemotherapy are the most common treatment choices for breast cancer. Doxorubicin (DOX) is one of the most regularly utilized medications in breast cancer protocols. However, DOX has showed numerous side effects including lethal cardiotoxicity. This study aims to fortify DOX cytotoxicity and lowering its side effects via its combining with the antidiabetic metformin (MET) as an adjuvant therapy, along with its effective delivery using natural platelet-rich plasma (PRP), and newly-developed PRP-mimicking nanocapsules (NCs). The PRP-mimicking NCs were fabricated via layer-by-layer (LBL) deposition of oppositely charged biodegradable and biocompatible chitosan (CS) and alginate (ALG) on a core of synthesized polystyrene nanoparticles (PS NPs) followed by removal of the PS core. Both natural PRP and PRP-mimicking NCs were loaded with DOX and MET adjuvant therapy, followed by their physicochemical characterizations including DLS, FTIR, DSC, and morphological evaluation using TEM. In-vitro drug release studies, cytotoxicity, apoptosis/necrosis, and cell cycle analysis were conducted using MCF-7 breast cancer cells. Also, an in-vivo assessment was carried out using EAC-bearing balb/c mice animal model to evaluate the effect of DOX/MET-loaded natural PRP and PRP-mimicked NCs on tumor weight, volume and growth biomarkers in addition to analyzing the immunohistopathology of the treated tissues. Results confirmed the development of CS/ALG-based PRP-mimicking NCs with a higher loading capacity of both drugs (DOX and MET) and smaller size (259.7 ± 19.3 nm) than natural PRP (489 ± 20.827 nm). Both in-vitro and in-vivo studies were in agreement and confirmed that MET synergized the anticancer activity of DOX against breast cancer. Besides, the developed LBL NCs successfully mimicked the PRP in improving the loaded drugs biological efficiency more than free drugs.

Facile Synthesis and Characterizations of Mixed Metal Oxide Nanoparticles for the Efficient Photocatalytic Degradation of Rhodamine B and Congo Red Dyes.

Photocatalytic degradation has been suggested to be a cheap and efficient way to dispose of organic pollutants, such as dyes. Therefore, our research team strives to produce nanophotocatalysts in a simple and inexpensive way. In this work, the Pechini sol-gel technique was employed for the facile synthesis of Mn0.5Zn0.5Fe2O4/Fe2O3 and Fe0.5Mn0.5Co2O4/Fe2O3 as mixed metal oxide nanoparticles for the efficient photocatalytic degradation of Rhodamine B and Congo Red dyes. XRD, FT-IR, a N2 adsorption/desorption analyzer, EDS, FE-SEM, and an UV-Vis diffuse reflectance spectrophotometer were used to characterize the produced samples. The XRD patterns revealed that the average crystallite size of the Fe0.5Mn0.5Co2O4/Fe2O3 and Mn0.5Zn0.5Fe2O4/Fe2O3 samples is 90.25 and 80.62 nm, respectively. The FE-SEM images revealed that the Fe0.5Mn0.5Co2O4/Fe2O3 sample consists of cubic and irregular shapes with an average diameter of 1.71 µm. Additionally, the Mn0.5Zn0.5Fe2O4/Fe2O3 sample consists of spherical shapes with an average diameter of 0.26 µm. The energy gaps of the Fe0.5Mn0.5Co2O4/Fe2O3 and Mn0.5Zn0.5Fe2O4/Fe2O3 samples are 3.50 and 4.3 eV and 3.52 and 4.20 eV, respectively. In the presence of hydrogen peroxide, the complete degradation of 100 mL of 20 mg/L of Rhodamine B and Congo Red dyes occurred at pH = 8 and 3, respectively, within 50 min, using 0.1 g of the synthesized samples.

Functionalized MOF as a Sensitive Spectroscopic Probe for Hg2+, Co2+, and Al3+ Ions Detection in Aqueous Media.

A modified metal-organic framework (MOF) named Al-MIL-53-N=SA-Br was synthesized via a Schiff-base reaction between the MOFs (Al-MIL-53-NH2) and 5-bromo salicylaldehyde. The robust functionalized Al-MIL-53-N=SA-Br was used as a novel spectrophotometric sensor for detecting Hg2+, Co2+, and Al3+ ions. In a wide range of concentrations, the absorption spectral intensity of Al-MIL-53-N=SA-Br increased linearly upon increasing the concentration of Hg2+, Co2+, and Al3+ ions. The limit of detection (LOD) of the proposed Al-MIL-53-N=SA-Br sensor reached 1.52 ppm of Hg2+ ion (7.56 × 10-9 M). Therefore, this study introduces a novel ratiometric Hg2+, Co2+, and Al3+ ions chemosensor. Simple treatment using thiourea or ethylenediaminetetraacetic acid can remove the metal ions from the used sensor and use it many times with a high efficiency. In addition, the Al-MIL-53-N=SA-Br sensor has a high adsorption capacity for these metal ions. The design of the robust Al-MIL-53-N=SA-Br sensor provided high stability, reproducibility, selectivity, high sensitivity, and a facile sensing design. Furthermore, the good absorption spectral stability of Al-MIL-53-N=SA-Br in aqueous media, the broad linear in sensing, and the low LOD of the Hg2+, Co2+, and Al3+ ions show its high potential in determining these ions in real water.

Fabrication of hybrid nanocomposite derived from chitosan as efficient electrode materials for supercapacitor.

A novel high-performance supercapacitor was fabricated using spinal (nickel ferrite) nanoparticles uniformly implanted into nitrogen-doped carbon matrix. The nanocomposite was fabricated with bimetallic polymer complexes for the first time. The fabricated nanocomposite was characterized using FTIR, TGA, Raman, XRD, BET, XPS, SEM and TEM technique. The nanocomposite used as the electrode material for assembling electrodes for supercapacitor over nickel foam, and show an excellent specific capacitance of 958.33 F g-1 at a current density of 5.0 A g-1 in a two-electrode system, using 6 M KOH solution as electrolyte. The energy density was observed 43.75 Wh kg-1 at a power density of 516.25 W kg-1, moreover, at a high power density of 882 W kg-1, it still attains the energy density of 26.25 W h kg-1 and, supports the well-known Ragone plot. The high cycling stability (9.75% loss over 6000 cycles) has been demonstrated and shows excellent stability. The results manifest the great potential of this nanocomposite for next-generation high-power applications. Thus, an advanced electrode material for high-performance supercapacitor was successfully assembled first time by a simple and scalable synthesis route.

Apparent diffusion coefficient mapping of salivary gland tumors: prediction of the benignancy and malignancy.

BACKGROUND AND PURPOSE: Preoperative prediction of tumor malignancy is clinically very important, because this information strongly influences the surgical plan. We evaluate the preoperative apparent diffusion coefficient (ADC) maps of benign and malignant salivary gland tumors. MATERIALS AND METHODS: High-resolution MR imaging was performed on 31 patients with benign or malignant salivary gland tumors; ADC maps of the tumors were also obtained. Surface coils of 47 or 110 mm diameter were used to improve the image resolution. The ADCs were compared with histologic features of the excised tumors. RESULTS: The ADC maps effectively depicted the histologic features of the salivary gland tumors, such as presence of cancer cells, myxomatous tissues, fibrosis, necrosis, cyst formation, and lymphoid tissues. The ADC maps showed that more frequent areas with high ADCs (> or = 1.8 x 10(-3) mm(2)/s) were significantly greater in benign tumors than in malignant tumors. The sensitivity and specificity for high ADC occupying fewer than 5% of the area of a tumor was 89% and 100%, respectively, resulting in 97% accuracy, 100% positive predictive value, and 96% negative predictive value. CONCLUSION: The ADC may provide preoperative tissue characterization of the salivary gland tumors.

Plasmodium falciparum sexual stage antigens: immunogenicity and cell-mediated responses.

Antibody and cell-mediated immune responses to the transmission-blocking target antigens of Plasmodium falciparum, Pfs 48/45, were determined in infected non-immune patients and in immune individuals from an endemic area. Characterization of the B cell epitopes with monoclonal antibodies showed that there were five regions identifiable but there could be interactions between them causing either competitive or enhancing effects. Sera from infected non-immune patients contained antibodies that would compete with one or more of the mAbs to the different epitopes. Immune responsiveness to purified Pfs 48/45 in P. falciparum-immune adults measured as lymphoproliferation, production of interferon-gamma, or as Pfs 48/45-specific antibody was very limited. This did not appear to be due to MHC class II restriction, to diversity in structure of the parasite antigens or to a failure of immunological memory. The antibody-response data were more consistent with down-regulation of immunity as a result of prolonged exposure to infection.

Reshaping human monoclonal antibodies for imaging and therapy.

Current problems in obtaining suitable monoclonal antibodies (MoAbs) for in vivo imaging and therapy can now be bypassed using protein-engineering rather than conventional hybridoma technology. Rodent antibody binding sites can be grafted onto human acceptor antibodies thus reshaping the human MoAbs into reagents with more desired specificities. We successfully exploited this technology to produce two reshaped human antibodies with the same specificities and very similar binding abilities as demonstrated for the mouse antibodies H17E2 and HMFG1.

Isolation and characterization of proteinases from the sarcocarp of snake-gourd fruit.

Seven proteinases were isolated from the fruit of snake-gourd, Trichosanthes cucumeroides Maxim. Their isozymes are all serine proteinases, and homologous in their respective molecular weights, amino acid compositions, and enzymatic properties. Their molecular weight was estimated to be about 50,000. Using casein as a substrate, the maximum activity was found in the alkaline pH region. The optimum temperature using casein was 70 degrees C at pH 7.3. The enzymes were strongly inhibited by diisopropyl fluorophosphate and not inhibited by inhibitors of sulfhydryl or metalloproteases. The reduced and S-carboxymethylated insulin B-chain was used as a substrate in an investigation of the specificity. The enzyme was found to have a wide specificity for this substrate but preferentially hydrolyzed the peptide bonds involving the carboxyl groups of charged amino acid such as S-cm-cysteine, glutamic acid, histidine, arginine, and lysine. Experimental evidence indicated that the snake-gourd proteinases are similar in their properties to cucumisin, which is isolated from the sarcocarp of melon fruit.

High frequency of antibody response to Plasmodium falciparum gametocyte antigens during acute malaria infections in Papua New Guinea highlanders.

Sera from 62 adult Papua New Guinea highlanders with suspected acute malaria were tested by competitive ELISA for the presence of antibodies capable of inhibiting binding of 8 monoclonal antibodies (Mabs) directed against epitopes on gametocytes of Plasmodium falciparum. Between 33% and 72% of the malaria cases were inhibitory, depending on the Mab. There was no difference between the proportion of persons with P. falciparum (asexuals or gametocytes) and P. vivax whose sera inhibited Mab binding, but all 3 categories had a significantly higher proportion of inhibitors than persons who were malaria negative. The amount of gametocyte antibody recognizing epitopes on Pfs 48/45 and Pfs 230 increased with increasing numbers of previous malaria episodes. The proportion of sera from these relatively nonimmune adults which had gamete antibodies was similar to the proportion seen in sera from a highly endemic area, suggesting that antibody responses to these epitopes are a part of the initial response observed after a limited number of malaria episodes.

Contribution of doppler sonography blood flow information to the diagnosis of metastatic cervical nodes in patients with head and neck cancer: assessment in relation to anatomic levels of the neck.

BACKGROUND AND PURPOSE: Although sonographic evaluation of cervical adenopathy by use of size criteria is effective, the sensitivity and specificity fall short of that required to make adequate judgments regarding neck dissection. Therefore, we tested whether the combined use of size criteria and Doppler sonographic findings would improve the predictive ability for metastatic cervical nodes. METHODS: We analyzed 338 histologically proved cervical lymph nodes (108 metastatic and 230 nonmetastatic) in 73 patients with head and neck cancer. The sonographic topography of the nodes was compared with dissected specimens, and their position in the neck was categorized into three levels (I, II, and III+IV). The diagnostic accuracy of sonography was evaluated by using the single criterion of short-axis diameter of the node or by the combined criteria of short-axis diameter and Doppler blood flow features (the absence or presence of normal hilar flow). RESULTS: As compared with the single criterion of short-axis nodal diameter, the combined criteria of nodal size and Doppler blood flow patterns increased the diagnostic accuracy of sonography at all levels in the neck. Accordingly, the best cut-off values were improved to 6, 7, and 5 mm for nodes at levels I, II, and III+IV, respectively. In addition, the combined criteria yielded high sensitivites (> or = 89%) and specificities (> or = 94%). CONCLUSION: Hilar blood flow information obtained by Doppler sonography significantly improves diagnostic accuracy for the detection of nodes metastatic from head and neck squamous cell carcinoma.

Malaria in adult outpatients at Goroka Hospital during 1986.

Of 206 adult outpatients attending Goroka Hospital with suspected malaria during 1986, 40.3% had blood slides positive for malaria (28.2% Plasmodium falciparum, 13.6% P. vivax and 1.9% P. malariae). Parasite densities and proportions of cases with gametocytes were higher than observed in endemic regions. Acquisition of infection during recent coastal travel was implicated in the majority of cases (86%). 6 out of 13 gametocyte carriers tested were infectious to Anopheles farauti mosquitos. Anti-malaria ELISA values in sera were elevated above non-immune values in over 75% of infections, although ELISA values were low compared to those in sera from residents of coastal areas, indicating the low level of previous exposure to malaria.

Apparent diffusion coefficient mapping for sinonasal diseases: differentiation of benign and malignant lesions.

BACKGROUND AND PURPOSE: CT and MR imaging features of benign and malignant sinonasal lesions are often nonspecific. Therefore, we evaluated the ADC-based differentiation of these lesions. MATERIALS AND METHODS: We retrospectively assessed ADCs of 61 patients with histologically proved sinonasal tumors and tumorlike lesions: 19 benign lesions, 28 malignant tumors, and 14 inflammatory lesions. Overall ADCs and percentages of total tumor area with extremely low, low, intermediate, or high ADCs (ADC mapping) were determined by using 2 b-values (500 and 1000 s/mm(2)). RESULTS: ADCs of malignant tumors (0.87 ± 0.32 × 10(-3) mm(2)/s) were significantly lower than those of benign (1.35 ± 0.29 × 10(-3) mm(2)/s, P < .0001) and inflammatory (1.50 ± 0.50 × 10(-3) mm(2)/s, P = .0002) lesions. On ADC mapping, percentages of total tumor area within malignant tumors having extremely low or low ADCs were significantly (P < .0001) greater than those within benign and inflammatory lesions. Cutoff points for ADC mapping (≥78% of tumor areas having extremely low or low ADCs) effectively differentiated benign or inflammatory lesions and malignant tumors with 75% sensitivity, 94% specificity, 85% accuracy, and 91% positive and 82% negative predictive values, respectively. ADCs also effectively discriminated lymphomas and SCCs from other malignant tumors. CONCLUSIONS: ADC mapping may be an effective MR imaging tool for the differentiation of benign/inflammatory lesions from malignant tumors in the sinonasal area.

Multiparametric MR imaging of sinonasal diseases: time-signal intensity curve- and apparent diffusion coefficient-based differentiation between benign and malignant lesions.

BACKGROUND AND PURPOSE: The sinonasal region is a platform for a broad spectrum of benign and malignant diseases, and image-based differentiation between benign and malignant diseases in this area is often difficult. Here, we evaluated multiparametric MR imaging with combined use of TICs and ADCs for the differentiation between benign and malignant sinonasal tumors and tumorlike diseases. MATERIALS AND METHODS: TICs obtained from dynamic contrast-enhanced MR imaging and ADCs were analyzed on a lesion-by-lesion (overall TIC and ADC) and pixel-by-pixel (TIC and ADC mapping) basis in patients with benign (n = 21) or malignant (n = 23) sinonasal tumors and tumorlike diseases. The TICs were semiautomatically classified into 5 distinctive patterns (flat, slow uptake, rapid uptake with low washout ratio, rapid uptake with high washout ratio, and miscellaneous). ADCs were determined by using b-values of 500 and 1000 s/mm(2). RESULTS: Malignant sinonasal tumors had small (<25%) areas of the type 1 flat TIC profile as determined by pixel-by-pixel TIC analysis and large (≥50%) areas of low or extremely low ADCs (≤1.2 × 10(-3) mm(2/)s) as determined by ADC mapping. Consequently, stepwise classification on the basis of TICs and ADCs successfully (at 100% accuracy) discriminated malignant from benign sinonasal diseases in the present patient cohort. CONCLUSIONS: Multiparametric MR imaging by using TICs and ADCs may help differentiate benign and malignant sinonasal diseases.

Immunological characteristics of a synthetic peptide associated with a catalytic domain of mutans streptococcal glucosyltransferase.

The immunogenicity of a multiple antigenic peptide construct consisting of four copies of the synthetic 21-mer peptide DANFDSIRVDAVDNVDADLLQ was measured. The composition of this peptide was derived from a sequence in the N-terminal region of mutans streptococcal glucosyltransferases (GTFs) containing an aspartic acid implicated in catalysis. The peptide (CAT) construct was synthesized as a tetramer on a lysine backbone and subcutaneously injected into Sprague-Dawley rats for polyclonal antibody formation or intraperitoneally injected into BALB/c mice, and then spleen cell fused with Sp2/0Ag14 murine myeloma cells for monoclonal antibody formation. The resulting rat antisera and mouse monoclonal antibodies reacted with CAT and with native GTF isozymes from Streptococcus sobrinus and Streptococcus mutans (in enzyme-linked immunosorbent assay and Western blot [immunoblot] analyses). Functional inhibition of the water-insoluble glucan synthetic activity of S. sobrinus GTF-I was demonstrated with an immunoglobulin M anti-CAT monoclonal antibody (> 80% inhibited) and with rat sera (approximately 17% inhibited). The monoclonal antibody preparation also modestly inhibited the water-soluble glucan synthetic activity of an S. mutans GTF mixture. These results suggest that the CAT peptide contains B-cell epitopes that are similar to those of intact mutans streptococcal GTFs and has the potential to elicit antibody that can inhibit GTF function. Thus, sequences within this peptide construct may have value for inclusion in a synthetic dental caries vaccine.