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1.
J Oral Maxillofac Surg ; 79(11): 2227-2239, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33838117

RESUMO

PURPOSE: Trigeminal neuralgia (TN) refractory to pharmacotherapy requires surgical interventions which vary from percutaneous procedure to microvascular decompression (MVD). The aim of the systematic review is to find evidence for the surgical treatment for TN with high success rate and low complications which improves the quality-of-life (QOL). METHODS: A systematic literature search was made on published studies from MEDLINE, SCOPUS, Science Direct, and Cochrane Library databases that report the available surgical treatment for TN up to March 2020 and studies referred in the selected papers. Relevant studies were selected based on predefined eligibility criteria. The primary outcome measured was success rate, pain relief and secondary outcome measured was QOL, recurrence and complication rate. RESULTS: Ten studies with a sum of 11,154 individuals were included in this qualitative analysis. Seven studies compared MVD whereas 4 studies compared Gamma knife radiosurgery with other techniques like percutaneous balloon compression, percutaneous glycerol rhizotomy etc. The result showed that MVD has a considerable higher rate of initial pain-free outcomes (96.6%) followed by Gamma knife radiosurgery (96.2%), cryotherapy (95.4%), percutaneous balloon compression (87%), percutaneous glycerol rhizotomy (85%) and the lowest rate of cohorts who were never pain-free (1.7%).QOL was improved to 100% as a result of pain relief which was evaluated in only 2 studies . Overall the recurrence rate was 0.45 to 52%. MVD has lower rate of long-term recurrence 0.45 and 6.1% for 2 years and 8 years, respectively, and cryotherapy has the highest rate of 52% at 6 months. CONCLUSION: Outcomes of the literature search showed that it lacks the knowledge to generally support 1 or the other treatment. Each type of TN requires individualized protocols to treat based on pain response which ultimately improve the QOL. We also propose there should be more reliable data reporting by using a universally acceptable pain scale for better analysis of treatment outcome.


Assuntos
Cirurgia de Descompressão Microvascular , Radiocirurgia , Neuralgia do Trigêmeo , Humanos , Recidiva Local de Neoplasia , Qualidade de Vida , Estudos Retrospectivos , Resultado do Tratamento , Neuralgia do Trigêmeo/tratamento farmacológico , Neuralgia do Trigêmeo/cirurgia
2.
J Craniofac Surg ; 30(5): e460-e462, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31299814

RESUMO

Postburn maxillofacial deformities, although rare, are a significant cause of morbidity. Since contracture scars have a potential role in deforming the maxillofacial skeleton, the focus of treatment should be on growing patients, where scar contractures can drastically influence growth and morphology of the maxillofacial units. There are certain aspects of severe facial burns and deformities, especially of the jaws, that deserve sincere attention to overcome aesthetic and functional disabilities such as inability to masticate and incompetent lips. The purpose of this article, therefore, is to discuss these injuries, the mechanism of development of deformities of the jaws and associated structures and their management for better aesthetic, functional, and psychological health of patient. An interpretive clinical report is presented.


Assuntos
Queimaduras/cirurgia , Traumatismos Faciais/cirurgia , Anormalidades Maxilofaciais/cirurgia , Modalidades de Fisioterapia , Adulto , Queimaduras/complicações , Cicatriz/cirurgia , Contratura/cirurgia , Traumatismos Faciais/complicações , Humanos , Masculino , Mastigação , Anormalidades Maxilofaciais/etiologia , Anormalidades Maxilofaciais/terapia , Cirurgia Plástica
3.
J Pept Sci ; 21(11): 833-44, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26424213

RESUMO

The effect of glycosylation on protein structure and function depends on a variety of intrinsic factors including glycan chain length. We have analyzed the effect of distal sugar and interglycosidic linkage of disaccharides on the properties of proline-rich antimicrobial glycopeptides, formaecin I and drosocin. Their glycosylated analogs-bearing lactose, maltose and cellobiose, as a glycan side chain on their conserved threonine residue, were synthesized where these disaccharides possess identical proximal sugar and vary in the nature of distal sugar and/or interglycosidic linkage. The structural and functional properties of these disaccharide-containing formaecin I and drosocin analogs were compared with their corresponding monoglycosylated forms, ß-D-glucosyl-formaecin I and ß-D-glucosyl-drosocin, respectively. We observed neither major secondary structural alterations studied by circular dichroism nor substantial differences in the toxicity with mammalian cells among all of these analogs. The comparative analyses of antibacterial activities of these analogs of formaecin I and drosocin displayed that ß-D-maltosyl-formaecin I and ß-D-maltosyl-drosocin were more potent than that of respective ß-D-Glc-analog, ß-D-cellobiosyl-analog and ß-D-lactosyl-analog. Despite the differences in their antibacterial activity, all the analogs exhibited comparable binding affinity to DnaK that has been reported as one of the targets for proline-rich class of antibacterial peptides. The comparative-quantitative internalization studies of differentially active analogs revealed the differences in their uptake into bacterial cells. Our results exhibit that the sugar chain length as well as interglycosidic linkage of disaccharide may influence the antibacterial activity of glycosylated analogs of proline-rich antimicrobial peptides and the magnitude of variation in antibacterial activity depends on the peptide sequence.


Assuntos
Antibacterianos/química , Peptídeos Catiônicos Antimicrobianos/química , Desenho de Fármacos , Glicopeptídeos/química , Modelos Moleculares , Antibacterianos/síntese química , Antibacterianos/metabolismo , Antibacterianos/farmacologia , Peptídeos Catiônicos Antimicrobianos/síntese química , Peptídeos Catiônicos Antimicrobianos/metabolismo , Peptídeos Catiônicos Antimicrobianos/farmacologia , Sítios de Ligação , Configuração de Carboidratos , Dissacarídeos/química , Proteínas de Drosophila/química , Proteínas de Drosophila/metabolismo , Proteínas de Drosophila/farmacologia , Escherichia coli/efeitos dos fármacos , Escherichia coli/crescimento & desenvolvimento , Proteínas de Escherichia coli/química , Proteínas de Escherichia coli/metabolismo , Glicopeptídeos/síntese química , Glicopeptídeos/metabolismo , Glicopeptídeos/farmacologia , Glicoproteínas/química , Glicoproteínas/metabolismo , Glicoproteínas/farmacologia , Glicosilação , Proteínas de Choque Térmico HSP70/química , Proteínas de Choque Térmico HSP70/metabolismo , Proteínas de Insetos/química , Proteínas de Insetos/metabolismo , Proteínas de Insetos/farmacologia , Cinética , Testes de Sensibilidade Microbiana , Peso Molecular , Prolina/química , Conformação Proteica , Estrutura Secundária de Proteína , Salmonella typhimurium/efeitos dos fármacos , Salmonella typhimurium/crescimento & desenvolvimento , Técnicas de Síntese em Fase Sólida
4.
Chembiochem ; 13(2): 282-92, 2012 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-22162268

RESUMO

Fluorescent labeling has enabled a better understanding of the relationships between receptor location, function, and life cycle. Each of these perspectives contributes new insights into drug action, particularly for G protein-coupled receptors (GPCRs). The aim of this study was to develop a fluorescein derivative, FLUO-QUIN-a novel antagonist of the cholecystokinin-B/gastrin receptor. A radioligand-binding experiment revealed an IC(50) of 4.79 nm, and the antagonist inhibited gastric acid secretion in an isolated lumen-perfused mouse stomach assay (up to 51 % at 100 nm). The fluorescence properties altered upon binding to the receptor, and the fluorophore was quenched to a greater extent when free than in the bound form. FLUO-QUIN specifically bound to human pancreatic carcinoma cells, MiaPaca-2, which are known to express the receptor, as evidenced by rapid clustering followed by time-dependent receptor internalization. This proves the stability of FLUO-QUIN and its ability to penetrate vesicular membranes and reach various cell targets. Hence it might be used as an agent for the detection of CCK-B-receptor-positive tumors by fluorescence imaging.


Assuntos
Células/efeitos dos fármacos , Fluoresceínas/síntese química , Neoplasias/diagnóstico , Quinazolinas/síntese química , Receptor de Colecistocinina B/antagonistas & inibidores , Tioureia/análogos & derivados , Animais , Benzodiazepinonas/farmacologia , Cromatografia Líquida de Alta Pressão , Fluoresceínas/química , Fluoresceínas/farmacologia , Corantes Fluorescentes , Antagonistas de Hormônios/farmacologia , Concentração Inibidora 50 , Camundongos , Modelos Moleculares , Estrutura Molecular , Quinazolinas/química , Quinazolinas/farmacologia , Tioureia/síntese química , Tioureia/química , Tioureia/farmacologia , Células Tumorais Cultivadas
5.
Glycoconj J ; 28(8-9): 537-55, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21968924

RESUMO

The synthetic glycopeptides are interesting model systems to study the effect of O-glycosylation in modulating their function and structure. A series of glycosylated analogs of two antibacterial peptides, formaecin I and drosocin, were synthesized by varying the nature of sugar and its linkage with bioactive peptides to understand the influence of structure variation of glycosylation on their antibacterial activities. Higher antibacterial activities of all glycopeptides compared to their respective non-glycosylated counterparts emphasize in part the importance of sugar moieties in functional implications of these peptides. The consequences of the unique differences among the analogs were apparent on their antibacterial activities but not evident structurally by circular dichroism studies. We have shown that differently glycosylated peptides exhibit differential effect among each other when tested against several Gram-negative bacterial strains. The change of monosaccharide moiety and/or its anomeric configuration in formaecin I and drosocin resulted into decrease in the antibacterial activity in comparison to that of the native glycopeptide, but the extent of decrease in antibacterial activity of glycosylated drosocin analogs was less. Probably, the variation in peptide conformation arising due to topological dissimilarities among different sugars in the same peptide resulting in possible modulation in binding properties appears to be responsible for differences in their antibacterial activities. Indeed, these effects of glycosylation are found to be sequence-specific and depend in the milieu of amino acid residues. Interestingly, none of the carbohydrate variants affected the basic property of these peptides, which is non-hemolytic and non-toxicity to eukaryotic cells.


Assuntos
Antibacterianos/farmacologia , Glicopeptídeos/farmacologia , Glicoproteínas/farmacologia , Proteínas de Insetos/farmacologia , Sequência de Aminoácidos , Animais , Antibacterianos/síntese química , Antibacterianos/química , Peptídeos Catiônicos Antimicrobianos , Bactérias/efeitos dos fármacos , Configuração de Carboidratos , Sequência de Carboidratos , Morte Celular/efeitos dos fármacos , Dicroísmo Circular , Eritrócitos/efeitos dos fármacos , Glicopeptídeos/síntese química , Glicopeptídeos/química , Glicoproteínas/síntese química , Glicoproteínas/química , Glicosilação/efeitos dos fármacos , Hemólise/efeitos dos fármacos , Proteínas de Insetos/síntese química , Proteínas de Insetos/química , Camundongos , Testes de Sensibilidade Microbiana , Dados de Sequência Molecular , Ratos
6.
J Craniomaxillofac Surg ; 48(3): 251-260, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32122727

RESUMO

PURPOSE: To compare and evaluate pain and healing following orthodontic tooth extraction using Low Level Laser Therapy [LLLT] and Cryotherapy. MATERIALS AND METHODS: 62 patients referred for orthodontic extraction of bilateral bicuspids were included. Subjects were alternatively divided into two groups with 31 patients each. One of the bilateral extraction sites was subjected to either intervention, LLLT or Cryotherapy, while the other site was kept as control. Pain was assessed for 7 consecutive days by Visual Analogue Scale and Wound healing on 4th, 7th and 14th days using a modified wound healing scale. RESULTS: Pain scores were generally better for Group I [LLLT] when compared to Group II [Cryotherapy] on all days. The highest mean score for pain observed on the 1st post-extraction day was 4.00 ± 0.93 and 4.16 ± 0.93 for Group I and Group II respectively [p = 0.42]. It was also observed that LLLT helped in better wound healing as compared to cryotherapy with a significant difference in wound healing on 7th [mean score for Group I and Group II- 1.16 ± 0.52 and 1.6 ± 0.62 respectively: p = 0.01] and 14th [mean score Group I and Group II- 0.23 ± 0.43 and 1.0 ± 0.58 respectively: p = 0.00] post-extraction days. CONCLUSION: LLLT has better analgesic and wound healing properties as compared to Cryotherapy, suggesting that LLLT should be preferred over cryotherapy whenever possible.


Assuntos
Terapia com Luz de Baixa Intensidade , Crioterapia , Humanos , Dor , Manejo da Dor , Extração Dentária , Cicatrização
7.
J Hazard Mater ; 377: 274-283, 2019 09 05.
Artigo em Inglês | MEDLINE | ID: mdl-31173976

RESUMO

In the present investigation, Graphite intercalation compound (GIC) functionalized phenolic resin based carbon foam for removal of arsenic (As(V)) from contaminated water is developed by sacrificial template technique followed by carbonization at 1000 °C in N2. The GICCF adsorbent is characterised by scanning electron microscope (SEM) for morphological study, X-ray diffraction (XRD) patterns explains the phase information and interlayer spacing of the adsorbent, whereas Fourier Transform Infrared Spectroscopy (FTIR) and X-ray Photoelectron Spectroscopy (XPS) gives the information about surface functionality and mechanism of adsorption of As(V) over the surface of adsorbent. The time data is fitted well in pseudo second order kinetics and follows multilinear nature of intra-particle diffusion model. The adsorption nature of adsorbent and adsorbate is explained by Langmuir isotherm better than Freundlich isotherm, Temkin isotherm, and D-R isotherm. The adsorption capacity of adsorbent is 62.5 µgg-1, which is calculated by Langmuir isotherm. Arsenic removal by GICCF is taken place within two hrs up to acceptable limit. The proposed GICCF can be regenerated after treating with 0.1 M HNO3 and 0.1 M HCl solution and it can be used for multiple times.

8.
J Craniomaxillofac Surg ; 46(3): 446-452, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29311020

RESUMO

PURPOSE: The purpose of this prospective, randomized, comparative clinical study was to compare treatment outcome of removal of foci and incision and drainage, with or without oral antibiotic therapy, in the management of single primary maxillofacial space infection with a known focus. MATERIALS AND METHODS: A total of 40 patients with single primary maxillofacial space infection with a known infectious focus were divided into two groups, one treated with incision and drainage only, and the other with incision and drainage along with oral antibiotics. The focus of infection was addressed in both groups. Parameters evaluated included pain score, maximum mouth opening, swelling, purulent discharge and return to normal life, which were assessed on days 1, 2, 3, 5 and 7. The patients were followed up until they reported return to normal life as assessed by a questionnaire. RESULTS: All of the patients rapidly responded to treatment as observed by a reduction in pain, swelling, discharge, and improvement in mouth opening. Pus discharge stopped within first 3 days in 75% of patients. The patients who underwent immediate extraction showed a faster resolution of infection (mean return to normal life = 9 days) than others (mean = 11.2 days). There was no statistically significant difference between the two groups for the five study parameters (p < 0.05). Of the total pus specimens, 75% had no significant bacterial growth, or grew 'oral flora'/contaminants, while only 25% grew specific bacteria. CONCLUSION: This study questions the conventional practice by dental practitioners and surgeons of prescribing antibiotics to all patients with odontogenic infection. Microbial culture and antibiotic sensitivity is of little therapeutic value in selected patient groups.


Assuntos
Antibacterianos/uso terapêutico , Infecções Bacterianas/tratamento farmacológico , Doenças da Boca/tratamento farmacológico , Doenças da Boca/microbiologia , Adolescente , Adulto , Bactérias/isolamento & purificação , Infecções Bacterianas/microbiologia , Criança , Feminino , Humanos , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Estudos Prospectivos , Adulto Jovem
9.
Medchemcomm ; 8(7): 1561-1574, 2017 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-30108868

RESUMO

Advanced malignant stages of pancreatic cancer have poor prognosis and very few treatment strategies are available. Pancreatic cancer is known to possess unique growth-related receptors that when activated, stimulate tumour proliferation. Gastrin and its related peptide cholecystokinin (CCK) are also significantly involved in the growth of this cancer type as well as other malignancies through activation of the cholecystokinin-B receptor (CCK-BR). New treatment strategies with CCK-BR antagonists are being suggested that suppress the growth promoting effects of gastrin. In this paper, we report the development of two series of quinazolinone derivatives incorporating hydrazinecarbothioamide (compounds 3a-g) and the hydrazino group (compounds 4a-e) as linkers for developing CCK-BR antagonists. The affinities of the compounds were determined using docking into the CCK-BR homology modeled structure. The compounds were tested for in vitro CCK-BR binding and gastric acid secretion in an isolated lumen-perfused mouse stomach assay. The compounds exhibited CCK-BR binding activity (IC50) in the range of 0.2-975 nM and showed good gastric acid secretion inhibitory activity. Molecular modeling of the compounds was done and pharmacophore mapping results showed good prediction of in vitro activity which correlated well with the experimental antagonistic activity. The compounds were further tested for their cytotoxicity on CCK-BR expressing pancreatic cancer cells. The results of the study provided two potent CCK-BR antagonists which also possess good to moderate growth inhibitory activities against pancreatic cancer cells.

10.
ACS Appl Mater Interfaces ; 8(16): 10600-8, 2016 04 27.
Artigo em Inglês | MEDLINE | ID: mdl-27035889

RESUMO

Lightweight and easily foldable with high conductivity, multiwalled carbon nanotube (MWCNT)-based mesocarbon microbead (MCMB) composite paper is prepared using a simple, efficient, and cost-effective strategy. The developed lightweight and conductive composite paper have been reported for the first time as an efficient electromagnetic interference (EMI) shielding material in X-band frequency region having a low density of 0.26 g/cm(3). The investigation revealed that composite paper shows an excellent absorption dominated EMI shielding effectiveness (SE) of -31 to -56 dB at 0.15-0.6 mm thickness, respectively. Specific EMI-SE of as high as -215 dB cm(3)/g exceeds the best values of metal and other low-density carbon-based composites. Additionally, lightweight and easily foldable ability of this composite paper will help in providing stable EMI shielding values even after constant bending. Such intriguing performances open the framework to designing a lightweight and easily foldable composite paper as promising EMI shielding material, especially in next-generation devices and for defense industries.

11.
Eur J Med Chem ; 92: 637-47, 2015 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-25617693

RESUMO

Glycosylation is an essential post-translational modification for few antimicrobial peptides of Proline rich class. In the present study we have shown the importance of Thr glycosylation over Ser glycosylation in Drosocin. Difference of a methyl group makes glycosylated-Thr preferred over glycosylated-Ser and renders higher activity to the peptide, probably due to the rigid conformation provided by the glycosylated-Thr. The structural rigidity provided by glycosylated-Thr to Drosocin backbone was mimicked by substituting glycosylated-Thr11, Ser7 and Ser12 with Pro residues. The designed non-glycosylated analogue, P(7)P(11)P(12)-Drosocin, exhibited functional and structural properties similar to that of the native monoglycosylated peptide. The functional importance of stereospecificity of amino acids and sugar was further explored. Interestingly, (all D) p(7)p(11)p(12)-Drosocin failed to exhibit antimicrobial activity but had comparable binding affinity to DnaK, one of the proposed targets for Proline rich class of antibacterial peptides, as that of its L counterpart. However, Drosocin containing either L or D enantiomeric sugar, displayed antimicrobial activity and binding affinity to bacterial heat shock protein, DnaK. The flow cytometry (FACS) experiments revealed the internalization of Drosocins bearing enantiomeric sugars and P(7)P(11)P(12)-Drosocin but not of its d-enantiomer into bacteria suggesting the importance of stereospecificity of amino acids for membrane entry. Once internalized both enantiomeric peptides may behave similarly. This assumption was corroborated by in vitro activity of (all D) p(7)p(11)p(12)-Drosocin in cell free assay where it abrogated transcription/translation pathway similar to l-enantiomer but could not inhibit the same in whole cell assay. These research findings provide insights into the mode of action of Proline rich class of antibacterial peptides and guidelines for designing functionally equivalent non-glycosylated analogues of glycosylated antibacterial peptides.


Assuntos
Peptídeos Catiônicos Antimicrobianos/química , Peptídeos Catiônicos Antimicrobianos/farmacologia , Glicopeptídeos/química , Glicopeptídeos/farmacologia , Prolina/química , Treonina/química , Treonina/farmacologia , Relação Dose-Resposta a Droga , Glicosilação , Bactérias Gram-Negativas/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Estereoisomerismo , Relação Estrutura-Atividade
12.
Nucl Med Biol ; 31(8): 1087-95, 2004 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-15607491

RESUMO

A quinazolinone derivative as a novel non-peptidic CCK-B receptor antagonist designated as Qn-In, was synthesized, characterized by spectroscopic techniques and evaluated for radiopharmaceutical potential. The efficiency of labeling with (99m)Tc was greater than 98% and the complex was stable for about 7 hours at 37 degrees C in presence of serum. Affinity of Qn-In was determined to be in nanomolar range by competitive binding studies on cancer cell line MDA-MB-468. Bio-distribution of (99m)Tc labeled Qn-In in mice was examined by intravenous administration and time-activity curves were generated. The ligand showed binding to most of the organs, known to express CCK-B receptor. The lack of uptake in brain may be due to the inability of the complex to cross the blood-brain barrier. Our results show that (99m)Tc labeled Qn-In ligand provides a new template for further development of non-peptidic ligands for diagnosis and therapy of diseases related with CCK-B receptor.


Assuntos
Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/metabolismo , Hidrazonas/farmacocinética , Quinazolinas/farmacocinética , Receptor de Colecistocinina B/metabolismo , Animais , Linhagem Celular Tumoral , Hidrazonas/química , Taxa de Depuração Metabólica , Camundongos , Especificidade de Órgãos , Quinazolinas/química , Coelhos , Cintilografia , Compostos Radiofarmacêuticos/síntese química , Compostos Radiofarmacêuticos/farmacocinética , Especificidade da Espécie , Distribuição Tecidual
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