ABSTRACT
Aims: This study aimed to investigate the effect of gallium nitrate [Ga(NO3)3], an inorganic antimicrobial agent, against the growth and biofilm formation of Staphylococcus aureus on the titanium surface. Study Design: This study is a laboratory investigation involving the determination of the inhibitory concentration (IC) of Ga(NO3) 3 against the planktonic strain of S. aureus and biofilm formation on titanium coupons. Place and Duration of Study: Sample: Center of Science and Technology for Sustainability (CCTS), Federal University of São Carlos, SP, Brazil, between March 2020 and March 2022. Methodology: The inhibitory concentration of gallium nitrate was determined in a 96-well microtiter plate in Muller Hinton broth. The potential of the antimicrobial agent to inhibit biofilm formation by S. aureus on titanium surfaces was evaluated by Scanning Electron Microscopy (SEM). The cytotoxicity potential of Ga(NO3)3 was determined on V79 cells. Results: The results showed that the susceptibility of gallium nitrate against S. aureus was 1.40 µM, while SEM images revealed that concentrations of 90 µM inhibited biofilm formation by S. aureus. Conclusion: This research has shown promising results regarding gallium nitrate's potential of inhibiting the growth of both planktonic and sessile S. aureus cells. In addition, coating titanium surfaces with Ga(NO3)3 would be an extra alternative to prevent implant-associated infections due to its non-toxicity to cells.
ABSTRACT
Objective To establish renal calculus rat model induced by calcifying nanoparticles .Methods We extracted and cultivated calcifying nanoparticles from clinically diagnosed patients with nephrolithiasis .Forty adult male SD rats were divided into 4 groups (n=10 each):group A(given an intravenous injection of calcifying nanoparticles) ,group B(given an intravenous injection of calcifying nanoparticles and taken Shenshitong granules) ,group C(given an intravenous injection of calcifying nanoparticles and intraperitoneal injection of gallium nitrate) ,group D (as normal control) .Eight weeks later ,all rats were sacrificed .The kidneys were examined for pathology .Results Histopathological studies revealed calcifying nanoparticles induced renal tubular epithelial cells fatty degeneration and renal tubular crystallization ,and caused renal interstitial infiltration with inflammatory cells .The forma‐tion of renal crystals in group A was more obvious than those in group B and C(P0 .05) .Conclusion Calcifying nanoparticles could cause renal tubular epithelial cells injury ,which leads to the formation of kidney stones .
ABSTRACT
Objective To study the effect of new type antiseptic gallium nitrate on the clearance of Staphylococcus aureus (S .aureus)biofilm,and explore new methods for suppressing bacterial biofilm formation.Methods Biofilm positive strains were screened among 14 clinically isolated S .aureus strains by crystal violet staining method,mini-mal inhibitory concentration (MIC)of gallium nitrate for biofilm positive strains and effect of gallium nitrate on the clearance of biofilm were measured.Results Of 14 S .aureus isolates,9 were biofilm positive strains;gallium ni-trate MICs for S .aureus ATCC 25923,biofilm-negative strain,and 9 biofilm positive strains were all 16 μg/mL;the clearance rate of gallium nitrate for early biofilm of S .aureus was significantly higher than mature biofilm ([86.53±0.96]% vs [62.54±1 .53]%,t=35.699,P <0.001 ).Conclusion Gallium nitrate can inhibit growth of S .aureus strains and clear biofilm,it can be applied in the prevention and control of S .aureus infection.
ABSTRACT
The aim of this study was to investigate the effect of gallium nitrate solution, an anti-resorption substance, when applied for root surface treatment in rat teeth submitted to delayed replantation, in order to inhibit the root resorption process and enhance repair. For such purpose, 20 maxillary right central incisors of rats were randomly assigned to 2 groups (n=10). In group I, root surface was treated with 10-4M gallium nitrate solution for 20 min, while in group II root surface was treated with 2 percent sodium fluoride for 20 min. All root canals were filled with a calcium hydroxide-based paste. At 15 and 60 days after replantation, the animals were killed and the specimens were processed in laboratory for light transmission microscopy. In both groups, there was mild occurrence of ankylosis and root resorption. The connective tissue formed at the periodontal ligament area was arranged parallel to the root in most specimens in both groups and presented signs of inflammation. In group I, there was periodontal pocket formation in all specimens at 60 days, revealing lack of repair. These findings contraindicate the use of gallium nitrate for root surface treatment of teeth submitted to late replantation.
Este trabalho teve como objetivo testar o efeito da solução de nitrato de gálio, uma substância anti-reabsortiva, quando usada no tratamento da superfície radicular de dentes reimplantados tardiamente, com o intuito de inibir o processo de reabsorção radicular e facilitar o reparo. Para isso, foram utilizados 20 incisivos centrais superiores direitos de ratos, divididos em 2 grupos (n=10). No grupo I, a superfície radicular foi tratada com solução de nitrato de gálio a 10-4M por 20 min e no grupo II com fluoreto de sódio a 2 por cento por 20 min. Todos os canais foram preenchidos com pasta de hidróxido de cálcio. Após 15 e 60 dias do reimplante, os animais foram mortos e as peças obtidas, processadas em laboratório para análise em microscópio de transmissão de luz. Em ambos os grupos, houve pequena ocorrência de anquilose e reabsorção radicular. O tecido conjuntivo formado no espaço do ligamento periodontal disposto paralelamente à raiz, na maioria dos espécimes dos dois grupos, mostrou-se inflamado e com algumas áreas de necrose. No grupo I, houve a formação de bolsa periodontal em todos os espécimes aos 60 dias, indicando a ausência de reparo. Estes achados desaconselham o uso do nitrato de gálio para o tratamento de superfície de dentes reimplantados tardiamente.