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1.
Exp Cell Res ; 430(1): 113687, 2023 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-37356748

RESUMO

BACKGROUND: The ability of cancer cells to be invasive and metastasize depend on several factors, of which the action of protease activity takes center stage in disease progression. PURPOSE/OBJECTIVE: To analyze function of new K21 molecule in the invasive process of oral squamous cell carcinoma (OSCC) cell line. MATERIALS & METHODS: The Fusobacterium (ATCC 23726) streaks were made, and pellets were resuspended in Cal27 (ATCC CRL-2095) OSCC cell line spheroid cell microplate. Cells were seeded and Lysotracker staining performed for CathepsinK red channel. Cell and morphology were evaluated using Transmission Electron microscopy. Thiobarbituric acid assay was performed. OSCC was analyzed for Mic60. Raman spectra were collected from the cancer cell line. L929 dermal fibroblast cells were used for Scratch Assay. ELISA muti arrays were used for cytokines and matrix molecules. Internalization ability of fibroblast cells were also analyzed. Structure of K21 as a surfactant molecule with best docked poses were presented. RESULTS: Decrease in lysosomal staining was observed after 15 and 30 min of 0.1% treatment. Tumor clusters were associated with cell membrane destruction in K21 primed cells. There was functional silencing of Mic60 via K21, especially with 1% concentration with reduced cell migration and invasiveness. Raman intensity differences were seen at 700 cm-1, 1200 cm-1 and 1600 cm-1 regions. EVs were detected within presence of fibroblast cells amongst K21 groups. Wound area and wound closure showed the progress of wound healing. CONCLUSION: Over expression of CatK can be reduced by a newly developed targeted K21 based drug delivery system leading to reduced migration and adhesion of oral squamous cell carcinoma cells. The K21 drug formulation can have great potential for cancer therapies due to targeting and cytotoxicity effects.


Assuntos
Carcinoma de Células Escamosas , Neoplasias de Cabeça e Pescoço , Neoplasias Bucais , Humanos , Carcinoma de Células Escamosas/patologia , Neoplasias Bucais/patologia , Carcinoma de Células Escamosas de Cabeça e Pescoço , Linhagem Celular Tumoral , Proliferação de Células , Catepsina K , Movimento Celular
2.
Artigo em Inglês | MEDLINE | ID: mdl-38830601

RESUMO

BACKGROUND: Treated or coated sutures promise to prevent contamination of wounds. PURPOSE: The purpose of the study was to coat surgical sutures with a new quaternary ammonium silane (QAS) antimicrobial compound at two different application temperatures and then to evaluate the resulting structural, physical, mechanical, and biological properties. STUDY DESIGN, SETTING, SAMPLE: In vitro and in vivo studies were conducted using male albino Wistar rats approved by the Joint Ethical Committee of IMU and Postgraduate Medical Institute, Lahore. Only suture samples, coated uniformly with verified presence of the compound and of adequate length were used. Samples which were not coated uniformly and with inadequate length or damaged were excluded. PREDICTOR VARIABLE: Predictor variables were sutures with and without QAS coatings and different temperatures. Sutures were coated with QAS at 0.5 and 1.0% wt/vol using the dip coating technique and sutures with and without QAS coating were tested at 25 and 40 °C temperatures. MAIN OUTCOME VARIABLE(S): Outcome variables of structural and physico-mechanical properties of QAS-coated and non-coated sutures were measured using Fourier transform infrared spectroscopy (for structural changes), confocal laser and scanning electron (for diameter changes), and tensile strength/modulus (for mechanical testing). Biologic outcome variables were tested (bacterial viability); macrophage cultures from Wistar rats were tested (M1/M2 polarization detecting IL-6 and IL-10). Macrophage cells were analyzed with CD80+ (M1) and CD163+ (M2). Chemotaxis index was calculated as a ratio of quantitative fluorescence of cells. COVARIATES: Not applicable. ANALYSES: Ordinal data among groups were compared using the Wilcoxon Mann-Whitney U test along with the comparison of histological analysis using the Wilcoxon Sign-rank test (P < .05). RESULTS: Fourier transform infrared spectroscopy peak at 1490 cm-1 confirmed the presence of QAS on suture's surfaces with a significant increase (P < .05) in diameter (0.99 ± 0.5-mm) and weight (0.77 ± 0.02-mg) observed for 1% QAS groups treated at 40 °C. Non-coated samples heated at 25 °C had significantly (P < .05) less diameters (0.22 ± 0.03-mm) and weights (0.26 ± 0.06-mg). Highest tensile strength/modulus was observed for 0.5% QAS-coated samples which also had significantly higher antibacterial characteristics than other sutures (P < .05). QAS-coated sutures significantly increased M1 and M2 markers. CONCLUSION AND RELEVANCE: QAS coating conferred antibacterial action properties without compromising the physical and mechanical properties of the suture.

3.
J Pak Med Assoc ; 70(12(B)): S14-S17, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33582716

RESUMO

OBJECTIVE: To determine the association between site and size of perforation of the tympanic membrane and the level of conductive hearing. METHODS: The cross-sectional study was conducted from November 2015 to October 2016 at Aga Khan University Hospital Karachi and comprised patients with tympanic membrane perforation without any other middle-ear disease. Karl-Storz Rigid Endoscope attached to a camera was used to take pictures of the tympanic membrane. Site of the perforation was determined using a vertical line to divide the membrane into two anterior and posterior halves. Size of the perforation was calculated as a percentage of the total membrane using Image J software. Data analysis was done using Stata 12. RESULTS: Of the 55 patients, 29(53%) were males and 26(47%) were females. The overall mean age was 33+/-15 years. With every 5% increase in the size of perforation, the hearing loss increased by 1 decibel. A difference of 5.5 decibels was noted between anterior and posterior perforations of similar size. CONCLUSION: Hearing loss increased with increase in the size of perforation.


Assuntos
Endoscópios , Perda Auditiva/etiologia , Internato e Residência , Otolaringologia/educação , Perfuração da Membrana Timpânica/diagnóstico por imagem , Adolescente , Adulto , Estudos Transversais , Feminino , Perda Auditiva/diagnóstico , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
4.
Odontology ; 105(1): 1-12, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27613193

RESUMO

Certain cell populations within periodontal tissues possess the ability to induce regeneration, provided they have the opportunity to populate the wound or defect. Guided regeneration techniques have been investigated for regenerating periodontal tissues and such therapies usually utilize barrier membranes. Various natural and synthetic barrier membranes have been fabricated and tested to prevent epithelial and connective tissue cells from invading while allowing periodontal cells to selectively migrate into the defect. This paper focuses on the literature relevant to the use and potential of resorbable collagen membranes in GBR procedures, sites of periodontal and intrabony defects, in cases of socket and alveolar ridge preservation and at implant sites. The results of their use in GBR procedures has shown them to be effective and comparable with non-resorbable membranes with regards to clinical attachment gain, probing depth reduction and defect bone filling. They have also shown to prevent epithelial ingrowth into the defect space during the initial wound healing phase postsurgically. Collagen membranes have also been used for root coverage and GBR procedures and have shown good success rates comparable to subepithelial connective tissue grafts and expanded-polytetrafluoroethylene (e-PTFE) membranes. The future for periodontal tissue engineering is very exciting with the use of barrier membranes expected to continue playing a critical role. However, long-term clinical trials are required to further evaluate and confirm the efficacy of the available collagen barrier membranes for periodontal and bone regeneration use.


Assuntos
Implantes Absorvíveis , Materiais Biocompatíveis , Colágeno/uso terapêutico , Regeneração Tecidual Guiada Periodontal/métodos , Membranas Artificiais , Regeneração Óssea , Humanos , Politetrafluoretileno
5.
J Ayub Med Coll Abbottabad ; 28(3): 627-629, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-28712254

RESUMO

Maxillary premolars exhibit variable root canal morphology, but it is quite rare to find three canals in their root system. The aim of this case report is to present the diagnosis and clinical management of a patient with anatomical variation of having three root canals in the maxillary first premolar. Three-canalled maxillary premolars are quite an endodontic challenge. A discussion is provided here to facilitate the early recognition of these canals, access cavity modifications for better intra-canal preparation and obturation procedures. Clinicians are required to be aware of the anatomical variations they may encounter when dealing with maxillary premolars and should be trained to apply this knowledge in the clinical scenario.


Assuntos
Dente Pré-Molar/anatomia & histologia , Raiz Dentária/anatomia & histologia , Dente Pré-Molar/diagnóstico por imagem , Humanos , Masculino , Maxila , Tratamento do Canal Radicular , Raiz Dentária/diagnóstico por imagem , Adulto Jovem
6.
Saudi Pharm J ; 24(5): 515-524, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27752223

RESUMO

Antimicrobial peptides (AMPs) are a wide-ranging class of host-defense molecules that act early to contest against microbial invasion and challenge. These are small cationic peptides that play an important in the development of innate immunity. In the oral cavity, the AMPs are produced by the salivary glands and the oral epithelium and serve defensive purposes. The aim of this review was to discuss the types and functions of oral AMPs and their role in combating microorganisms and infections in the oral cavity.

7.
Pak J Pharm Sci ; 29(3): 919-27, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-27166535

RESUMO

Hepatitis C virus (HCV) infection is a serious and significant global health problem in the Pakistan and elsewhere. In majority of cases HCV infection remains asymptomatic but in advance cases it may progress to fibrosis of liver, shrinkage of liver cells or failure of liver. The hepatitis C may progress to cause liver cirrhosis that mostly develop in 20% of the affected patients in 20 years with an increased risk in male, alcoholic drink, immune-compromised and who acquire HCV infection after the age of 40 years. This was an open-label prospective study conducted on 66 clinically and immunologically diagnosed cases of HCV infection. In Hepcinal treated group, there were significant improvement in HCV associated symptoms compared to control group (p<0.05). While Interferon therapy resulted in significant improvement in serological response (55.88%) compared to Hepcinal treated patients (46.88%). It was concluded that Hepcinal has shown better clinical response but no significant serological response (p=0.3244) and it might be an alternative therapy to treat hepatitis C infection and to prevent its progression into chronic ailment.


Assuntos
Antivirais/uso terapêutico , Hepatite C/tratamento farmacológico , Interferon-alfa/uso terapêutico , Preparações de Plantas/uso terapêutico , Ribavirina/uso terapêutico , Adulto , Antivirais/efeitos adversos , Quimioterapia Combinada , Feminino , Hepatite C/diagnóstico , Humanos , Interferon alfa-2 , Interferon-alfa/efeitos adversos , Masculino , Pessoa de Meia-Idade , Paquistão , Preparações de Plantas/efeitos adversos , Estudos Prospectivos , Proteínas Recombinantes/efeitos adversos , Proteínas Recombinantes/uso terapêutico , Ribavirina/efeitos adversos , Fatores de Tempo , Resultado do Tratamento , Adulto Jovem
8.
Pak J Pharm Sci ; 28(1): 43-7, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25553684

RESUMO

The topical herbal formulation Eezpain spray consisting of natural ingredients that have been clinically proved for its analgesic and anti-inflammatory activity. The designed formulation on application knee and wrist joints, back of neck and shoulder, forearms and lower back exhibited significant efficacy. A total of 20 subjects both male and female applied Eezpain spray consisting of Gaultheria oil, Eucalyptus oil, Turpentine oil, Clove Oil, Menthol and Camphor. All the active materials are cited that these have analgesic activity in myalgia and neuralgia. The study design was prospective and opens as pilot study followed the inclusion and exclusion criteria. All the sign and symptoms were noted at baseline and at the end of 14 days treatment performance was evaluated. The statistical analysis was done by using Microsoft Excel2007 and SPSS version 18.0. It is concluded that Eezpain spray has shown efficacy in mild to moderate cases on applying locally to the affected parts to relieve pain from different ailments.


Assuntos
Analgésicos/administração & dosagem , Mialgia/tratamento farmacológico , Preparações de Plantas/administração & dosagem , Administração Cutânea , Adulto , Aerossóis , Idoso , Artralgia/diagnóstico , Artralgia/tratamento farmacológico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mialgia/diagnóstico , Medição da Dor , Paquistão , Fitoterapia , Projetos Piloto , Plantas Medicinais , Estudos Prospectivos , Índice de Gravidade de Doença , Fatores de Tempo , Resultado do Tratamento
9.
Pak J Pharm Sci ; 28(6 Suppl): 2291-5, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26687746

RESUMO

Hypercholestriolemia is major risk factor that enhances the incidence of cardiovascular disease and coronary artery disease. The present study was conducted to normalize the lipid profile in the blood by using Biocor Plus for hypercholesterolemia compared with Simvastatin. It was prospective randomized case control study conducted on 70 diagnosed patients of hypercholesterolemia at Sohail Memorial Hospital, Karachi and Amir Habib Medical Center and Maternity Home, Karachi. Patients of both genders (30-70 years) with clinical diagnosis of Hypercholesterolemia. Sample sizes for this study included total of 70 subjects. There was statistically significant difference when comparing the effectiveness of test drug, Biocor Plus to control drug, Simvastatin for the treatment of primary hypercholesterolemia. This is clearly evident that the herbal coded test drug, Biocor Plus possesses a therapeutic value for the treatment of primary hypercholesterolemia. There were no untoward or significant side effects associated with the use of Biocor Plus that proved its good acceptability by the patients. Moreover there was subjective feeling of wellbeing regarding breathlessness and chest tightness or pressure in the patients taking Biocor Plus. This makes an interesting point to focus on this effective alternative drug for primary hypercholesterolemia.

10.
Dent J (Basel) ; 12(7)2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-39056983

RESUMO

(1) Introduction: Trust is a cornerstone of the patient-physician relationships. Unforeseen complications in the health care system could jeopardize patients' trust in their physicians. (2) Aim: This article presents a quantitative figure regarding foreseeing the necessity of a three-dimensional quantitative visualization of bone structure and concurrently preparing for an ancillary procedure by a dentist to successfully perform the surgery that could minimize unforeseen complications; (3) Materials and method: This retrospective study has been derived based on an analysis of 1134 patients who had received 4800 dental implants from January 2001 to August 2020, out of which 200 cases were randomly selected for this study. Each procedure during implant treatment was categorized as OPG (Orthopantomography) or OPG with CBCT as per all the procedures which included and were coded as follows, 1: Surgery & Restoration, 2: GBR (Guided Bone Regeneration), 3: GTR (Guided Tissue Regeneration), 4: Block Bone Graft, 5: Spreading, 6: Splitting, 7: Internal Sinus, 8: External Sinus, 9: PRF (Platelet Rich Fibrin). Any of the 200 cases in which implant placement could not have been performed for reasons related to a lack of CBCT were selected for this study. The surgery was aborted halfway through without implant placement in these cases due to a lack of bone quantity and/or lack of primary stability. These cases were registered for re-evaluation and statistical analysis; (4) Results: 7% of the cases that used OPG alone led the surgeon to unexpectedly abort in the middle of the surgery without implant placement. All (100%) of the patients who had CBCT during treatment planning were able to receive implants during the surgery. None of the patients left the surgery without receiving implants if CBCT was used (0%); (5) Discussion: Radiographic image quality is defined as the amount of information within the image that allows the radiologist to make a diagnostic decision with a particular level of certainty (Martin et al., 1999) and hence the importance of CBCT. The unexpected 7% of devastating situations for patients who started surgery but did not have implant placement led to [A] aborting the surgery, [B] procedural difficulties requiring an alternative treatment plan, [C] a negative impact on the patient's behavior, and [D] wanting to change doctor due to a lack of trust; (6) Conclusion: This study indicates that in implant dentistry patients' mistrust could be avoided by 7% if CBCT is obtained. It also shows the significance of cone-beam computed tomography as an adjunct to panoramic radiography during the diagnosis and treatment planning phase. The use of panoramic radiography alone can lead to a 7% likelihood of misdiagnosis. A lack of CBCT during treatment planning negatively affects the outcome of surgical procedures.

11.
J Burn Care Res ; 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38878005

RESUMO

Burn injuries related to Lithium-Ion batteries from personal mobility devices, such as electric bikes and electric scooters, have emerged as a global concern. By examining the literature, this study aims to provide an overview of the demographics, patterns and outcomes of personal mobility device-associated burns. A Singaporean cohort revealed burns resulting predominantly from fires occurring due to the combustion of unattended personal mobility device batteries during charging. In contrast, an Israeli cohort showed a higher TBSA and highlighted the vulnerability of limbs to burn injuries in such incidents. A Beijing cohort, consisting of paediatric patients, indicated potential child safety concerns regarding personal mobility device usage. Finally, a Shanghai cohort demonstrated the potential dangers of PMD battery chargers. The observed differences between those experiencing burn injuries and the broader population of personal mobility device riders in terms of age and gender suggest that younger males may be at higher risk, perhaps due to risky practices such as leaving personal mobility devices unattended whilst charging. This review emphasises the need for safety education, adherence to regulations, and responsible consumer choices to mitigate burn injuries. Recommendations include promoting child safety measures, using certified personal mobility devices, and cautious handling of DIY conversion kits. Further large-scale studies are essential to gain comprehensive insights and develop effective safety strategies to protect personal mobility device riders from burn injuries.

12.
J Funct Biomater ; 15(3)2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38535253

RESUMO

Three-dimensional printing (3DP) technology has revolutionized the field of the use of bioceramics for maxillofacial and periodontal applications, offering unprecedented control over the shape, size, and structure of bioceramic implants. In addition, bioceramics have become attractive materials for these applications due to their biocompatibility, biostability, and favorable mechanical properties. However, despite their advantages, bioceramic implants are still associated with inferior biological performance issues after implantation, such as slow osseointegration, inadequate tissue response, and an increased risk of implant failure. To address these challenges, researchers have been developing strategies to improve the biological performance of 3D-printed bioceramic implants. The purpose of this review is to provide an overview of 3DP techniques and strategies for bioceramic materials designed for bone regeneration. The review also addresses the use and incorporation of active biomolecules in 3D-printed bioceramic constructs to stimulate bone regeneration. By controlling the surface roughness and chemical composition of the implant, the construct can be tailored to promote osseointegration and reduce the risk of adverse tissue reactions. Additionally, growth factors, such as bone morphogenic proteins (rhBMP-2) and pharmacologic agent (dipyridamole), can be incorporated to promote the growth of new bone tissue. Incorporating porosity into bioceramic constructs can improve bone tissue formation and the overall biological response of the implant. As such, employing surface modification, combining with other materials, and incorporating the 3DP workflow can lead to better patient healing outcomes.

13.
Materials (Basel) ; 16(4)2023 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-36837334

RESUMO

The aim of this study was to evaluate published data regarding riboflavin (RF) as a cross-linker for improved adhesive bond strength to dentin and to analyze previous studies for optimal concentration of riboflavin range suitable for dentin bond. Saliva and distilled water were used as storage media and aging time was 24 h and 6 months. Results of meta-analysis were synthesized using a statistical method of inverse variance in random effects with a 95% Confidence Interval (CI). Cochrane review manager 5.4.1 was used to determine results of the meta-analysis. In total, 3172 articles were found from search databases "PubMed", "Scopus", and "Google Scholar". Six of the fifteen studies were eligible for meta-analysis. Micro tensile strength shows significant improvement with the addition of riboflavin (p < 0.05) compared to without the addition of riboflavin from with 95% CI. A significant difference has been found in micro tensile bond strength between use of the riboflavin cross-linker and without use of the riboflavin crosslinker in the dentin adhesive system. With a 95% confidence interval (CI), the I2 for micro tensile strength was 89% with strong heterogeneity, Chi2 = 44.76, df = 5 (p < 0.00001), and overall effect size is Z = 2.22 (p = 0.03) after immediate aging. Chiang et al. 2013 shows maximum mean differences which is 38.50 [17.93-59.07]. After 6 months of aging in distilled water or artificial saliva micro tensile bond strength has been increased with the addition of riboflavin (p < 0.05). It can be clearly seen that pooled effect and 95% CI did not cross the line of no effect. With a 95% confidence interval (CI), the I2 for micro tensile strength was 96% with strong heterogeneity, Chi2 = 117.56, df = 5 (p < 0.00001), and overall effect size is Z = 2.30 (p = 0.02). Subgroup analysis proved a similar effect of distilled water and artificial saliva as storage media on micro tensile bond strength after incorporating riboflavin as a collagen crosslinker. An artificial saliva aged forest plot also showed considerable heterogeneity with I2 = 96%; Tau2 = 257.32; Chi2 = 94.37; df = 2 (p < 0.00001); test for overall effect, Z = 1.06 (p = 0.29). Riboflavin prior to or with bonding is recommended to improve the bonding of different adhesive systems.

15.
Burns ; 48(4): 1013-1018, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-34602298

RESUMO

Our regional burns service has gained experience in managing paediatric hand friction burns due to vacuum cleaners (VC). We aimed to evaluate our 10 year experience managing these injuries as well as reviewing national data trends in order to identify those at risk of injury. MATERIALS AND METHODS: A International Burns Injury Database (IBID) request was made to review the number of burn injuries recorded due to Vacuum cleaner injuries (VCIs). In addition, a local IBID request was made to identify the number of burn injuries managed within our regional burns service. RESULTS: We identified 288 VCIs which have increasingly occurred in England and Wales between 1996-2020 and 32 children who sustained these injuries within our regional burns service. A general theme from both national and local data highlighted that these injuries occurred in males (78%, n=25) with a mean age of 20 months (9 months-4.5 years) affecting children's hands (94%). In 25 cases (78%) these injuries involved an interphalangeal joint. 85% (n = 27) of injuries were deep dermal/full thickness with eleven children (34%) undergoing surgical excision and skin grafts. DISCUSSION: Significant paediatric burn injuries can be sustained from VCs. Greater awareness is indicated for these injuries and legislation should be considered in order to improve the safety of vacuum cleaners. International burn societies are urged to collect data of these injuries in order to co-ordinate improved prevention strategies and change within the VC industry.


Assuntos
Queimaduras , Pediatria , Queimaduras/epidemiologia , Queimaduras/terapia , Criança , Fricção , Humanos , Lactente , Masculino , Estudos Retrospectivos , Transplante de Pele , Vácuo
17.
J Periodontol ; 91(11): 1521-1531, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32100284

RESUMO

BACKGROUND: Deproteinized bovine bone mineral (DBBM) has been extensively studied and used for bone regeneration in oral and maxillofacial surgery. However, it lacks an osteoinductive ability. We developed two novel bone anabolic conjugated drugs, known as C3 and C6, of an inactive bisphosphonate and a bone activating synthetic prostaglandin agonist. The aim was to investigate whether these drugs prebound to DBBM granules have the potential to achieve rapid and enhanced bone regeneration. METHODS: Bilateral defects (4.3 mm diameter circular through and through) were created in mandibular angles of 24 Sprague-Dawley rats were filled with DBBM Control, DBBM with C3 or DBBM with C6 (n = 8 defects per group/ each timepoint). After 2 and 4 weeks, postmortem samples were analyzed by microcomputed tomography followed by backscattering electron microscopy and histology. RESULTS: DBBM grafts containing the C3 and C6 conjugated drugs showed significantly more bone formation than DBBM control at 2 and 4 weeks. The C6 containing DBBM demonstrated the highest percentage of new bone formation at 4 weeks. There was no significant difference in the percentage of the remaining graft between the different groups at 2 or 4 weeks. CONCLUSIONS: DBBM granules containing conjugated drugs C3 and C6 induced greater new bone volume generated and increased the bone formation rate more than the DBBM controls. This is expected to allow the development of clinical treatments that provide more predictable and improved bone regeneration for bone defect repair in oral and maxillofacial surgery.


Assuntos
Substitutos Ósseos , Preparações Farmacêuticas , Animais , Regeneração Óssea , Substitutos Ósseos/farmacologia , Substitutos Ósseos/uso terapêutico , Bovinos , Membranas Artificiais , Minerais , Ratos , Ratos Sprague-Dawley , Microtomografia por Raio-X
18.
J Biomed Mater Res B Appl Biomater ; 108(6): 2670-2680, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32159274

RESUMO

Bone grafting procedures are commonly used to manage bone defects in the craniofacial region. Monetite is an excellent biomaterial option for bone grafting, however, it is limited by lack of osteoinduction. Several molecules can be incorporated within the monetite matrix to promote bone regeneration. The aim was to investigate whether incorporating bone forming drug conjugates (C3 and C6) within monetite can improve their ability to regenerate bone in bone defects. Bilateral bone defects were created in the mandible of 24 Sprague-Dawley rats and were then packed with monetite control, monetite+C3 or monetite+C6. After 2 and 4 weeks, post-mortem samples were analyzed using microcomputed tomography, histology and back-scattered electron microscopy to calculate the percentages of bone formation and remaining graft material. At 2 and 4 weeks, monetite with C3 and C6 demonstrated higher bone formation than monetite control, while monetite+C6 had the highest bone formation percentage at 4 weeks. There were no significant differences in the remaining graft material between the groups at 2 or 4 weeks. Incorporating these anabolic drug conjugates within the degradable matrix of monetite present a promising bone graft alternative for bone regeneration and repair in orthopedic as well as oral and maxillofacial applications.


Assuntos
Anabolizantes/farmacologia , Regeneração Óssea/efeitos dos fármacos , Fosfatos de Cálcio/farmacologia , Mandíbula/anormalidades , Anabolizantes/efeitos adversos , Anabolizantes/química , Animais , Substitutos Ósseos , Transplante Ósseo/métodos , Fosfatos de Cálcio/efeitos adversos , Fosfatos de Cálcio/química , Sobrevivência de Enxerto , Masculino , Osteogênese/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Microtomografia por Raio-X
19.
J Biomed Mater Res B Appl Biomater ; 108(1): 253-262, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31009177

RESUMO

Calcium phosphate-based biomaterials are extensively used for bone replacement and regeneration in orthopedic, dental, and maxillofacial surgical applications. The injury induced by surgical implantation of bone replacement graft materials initiates a cascade of host responses, starting with blood-biomaterial contact, protein adsorption on the material surface, blood coagulation, and leukocyte responses. During the initial acute inflammatory response, polymorphonuclear neutrophils (PMNs) and monocytes, abundant circulating leukocytes of the myeloid lineage, are recruited to the site of inflammation. In addition to responding to pathogenic challenges, these cells respond to particulate substances within the body including crystals of monosodium urate (MSU). Host responses toward grafts impact short- and long-term success in tissue engineering and regenerative applications. Although multinucleated osteoclasts, formed by monocyte/macrophage fusion, are generally thought to be responsible for resorption of implant biomaterials, the ability of different biomaterials to trigger PMNs, which are invariably present at the early stages after implant surgery, and are abundant in the oral cavity, has never been tested. In this article, we present analysis of the response of human blood-derived PMNs and monocytes toward brushite, monetite, and calcium polyphosphate (CPP) biomaterial substrates and compare this to the response to MSU crystals, the latter serving as a positive control. Employing multicolor flow cytometry to look at PMN and monocyte cell surface markers of activation to gauge the response to different biomaterials, we found that both types of myeloid cells are highly activated after exposure to brushite, monetite, and MSU but not CPP. © 2019 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater 108B:253-262, 2020.


Assuntos
Materiais Biocompatíveis/farmacologia , Substitutos Ósseos/farmacologia , Fosfatos de Cálcio/farmacologia , Leucócitos/metabolismo , Teste de Materiais , Polifosfatos/farmacologia , Humanos , Osteoclastos/metabolismo
20.
Int J Oral Maxillofac Implants ; 34(4): e51­e63, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30716148

RESUMO

PURPOSE: Achieving successful and predictable alveolar ridge augmentation in the vertical dimension is extremely challenging. Several materials have been investigated to achieve vertical ridge augmentation; however, the results are highly unpredictable. The collaborative team presenting this research has developed brushite- and monetite-based grafts that incorporate in their matrix a novel bone anabolic conjugate (C3) of a bisphosphonate and a potent bone-activating EP4 receptor agonist. The study objective was to investigate the potential of these graft formulations to achieve rapid, enhanced, and clinically significant bone regeneration in the vertical dimension. MATERIALS AND METHODS: Brushite and monetite grafts were fabricated and characterized for phase purity, porosity, compressive strength, and microstructural morphology. They were implanted in 12 rabbit calvaria for 12 weeks. Each group (n = 6): brushite control, brushite with C3, monetite control, and monetite with C3. Postmortem samples were retrieved and processed for analysis. The percentage bone volume, vertical bone height gained, and graft resorption were calculated and assessed. RESULTS: The brushite and monetite grafts containing C3 integrated well onto the calvarial bone surface, with new bone extending through the graft area (36% and 80%, respectively), while the C3 lacking grafts showed decreased surface integration and bone infiltration (28% and 38%, respectively). The C3 containing brushite and monetite grafts demonstrated bone growth vertically (1.8 mm and 2.7 mm, respectively) and improved graft resorption. CONCLUSION: The brushite- and monetite-based grafts loaded with the C3 conjugate resulted in greater de novo bone formation in the vertical dimension when compared with the grafts without the drug. However, the monetite grafts produced much more and predictable vertical height gain than was achieved with brushite grafts. The advantages of this new graft drug formulation in future would be to provide more predictable vertical bone regeneration, which will ultimately benefit patients undergoing dental implant placement.


Assuntos
Aumento do Rebordo Alveolar , Fosfatos de Cálcio , Crânio , Animais , Regeneração Óssea , Transplante Ósseo , Implantação Dentária Endóssea , Coelhos
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