Atovaquone, chloroquine, primaquine, quinine and tetracycline: antiproliferative effects of relevant antimalarials on Neospora caninum / Atovaquona, cloroquina, primaquina, quinino e tetraciclina: efeitos antiproliferativos de antimaláricos relevantes em Neospora caninum

Neospora caninum is an apicomplexan parasite that causes abortion in cattle, resulting in significant economic losses. There is no commercial treatment for neosporosis, and drug repositioning is a fast strategy to test possible candidates against N. caninum. In this article, we describe the effects of atovaquone, chloroquine, quinine, primaquine and tetracycline on N. caninum proliferation. The IC50 concentrations in N. caninum were compared to the current information based on previous studies for Plasmodium and Toxoplasma gondii, correlating to the described mechanisms of action of each tested drug. The inhibitory patterns indicate similarities and differences among N. caninum, Plasmodium and T. gondii. For example, atovaquone demonstrates high antiparasitic activity in all the analyzed models, while chloroquine does not inhibit N. caninum. On the other hand, tetracycline is effective against Plasmodium and N. caninum, despite its low activity in T. gondii models. The repurposing of antimalarial drugs in N. caninum is a fast and inexpensive way to develop novel formulations using well-established compounds.(AU)

Neospora caninum é um parasita Apicomplexa relacionado a abortos no gado bovino, que resultam em impactos econômicos. Não há tratamento comercial para neosporosis e o reposicionamento de drogas indica uma estratégia rápida para testar candidatos anti-N. caninum. Neste artigo, são descritos os efeitos da atovaquona, cloroquina, quinino, primaquine e tetraciclina na proliferação de N. caninum. As concentrações IC50 em N. caninum foram comparadas com a informação disponível, baseada em estudos publicados previamente para Plasmodium e Toxoplasma gondii, incluindo a correlação com os mecanismos de ação descritos para cada droga testada. Os padrões de inibição indicam pontos de similaridades e diferenças entre N. caninum, Plasmodium e T. gondii. Por exemplo, a atovaquona demonstra uma alta atividade antiparasitária em todos os modelos testados, enquanto a cloroquina não inibe N. caninum. Por outro lado, a tetraciclina é efetiva contra Plasmodium e N. caninum, em contraste com a baixa atividade em modelos de T. gondii. O reposicionamento de drogas antimaláricas em N. caninum é uma forma rápida e de baixo custo para o desenvolvimento de novas formulações que usam compostos bem estabelecidos.(AU)

Generation and characterization of U937-TR: a platform cell line for inducible gene expression in human macrophages.

Monocytes and macrophages are involved in a wide range of biological processes and parasitic diseases. The characterization of the molecular mechanisms governing such processes usually requires precise control of the expression of genes of interest. We implemented a tetracycline-controlled gene expression system in the U937 cell line, one of the most used in vitro models for the research of human monocytes and macrophages. Here we characterized U937-derived cell lines in terms of phenotypic (morphology and marker expression) and functional (capacity for phagocytosis and for Leishmania parasite hosting) changes induced by phorbol-12-myristate-13-acetate (PMA). Finally, we provide evidence of tetracycline-inducible and reversible Lamin-A gene silencing of the PMA-differentiated U937-derived cells.

Characterisation of penicillin and tetracycline resistance in Staphylococcus aureus isolated from bovine milk samples in Minas Gerais, Brazil.

This Regional Research Communication describes the characterisation of ampicillin, penicillin and tetracycline resistance in Staphylococcus aureus isolated from bovine subclinical mastitis in Minas Gerais State, Brazil. Ninety S. aureus isolates from bovine mastitis exhibiting phenotypic resistance to ampicillin, penicillin and/or tetracycline were selected for this study. The minimum inhibitory concentration (MIC) of each antibiotic was determined using the E-Test® and the production of beta-lactamase was determined by cefinase disks. The resistance genes blaZ, tet(K), tet(L), tet(M), and tet(O) were investigated by PCR in all of the isolates. The MIC results classified 77, 83 and 71% of the isolates as resistant to ampicillin, penicillin and tetracycline, respectively. The MIC50 and MIC90 were, respectively, 1 and 2 µg/ml for ampicillin, 0·5 and 1 µg/ml for penicillin and 32 and 64 µg/ml for tetracycline. Eighty-six per cent of beta-lactamase producing isolates were detected. Of the 90 isolates investigated, 97% amplified blaZ, 84% amplified tet(K), 9% amplified tet(L), 2% amplified tet(M) and 1% amplified tet(O). Seventy-nine isolates (88%) showed blaZ together with at least one tet gene. S. aureus isolates showed high MIC50 and MIC90 values for the three antimicrobials. The blaZ and tet(K) genes were widespread in the herds studied, and most of the isolates harboured blaZ and tet(K) concomitantly.

Comparison between two antimicrobial protocols with or without guided bone regeneration in the treatment of peri-implantitis. A histomorphometric study in dogs.

OBJECTIVES: This study used a dog model to evaluate two antimicrobial protocols with or without guided bone regeneration (GBR) in the surgical reconstruction of peri-implantitis defects. MATERIAL AND METHODS: Eight beagle dogs subject to ligature-induced peri-implantitis were used. The animals either received antimicrobial photodynamic therapy or topical tetracycline hydrochloride combined with GBR or as stand-alone surgical interventions. Block biopsies of the defect sites for histological analysis were obtained at euthanasia, 12 weeks postsurgery. The primary outcome of the study was re-osseointegration; secondary outcomes included alveolar bone gain and remaining defect characteristics. The effects of the implant site, early exposure, and type of antimicrobial protocol on bone regeneration were also evaluated. RESULTS: No significant differences were observed between the two antimicrobial protocols, and the adjunctive use of GBR failed to significantly improve re-osseointegration or bone gain using either protocol. Buccal sites and implant early exposure negatively affected bone regeneration. CONCLUSION: Both antimicrobial therapies stand-alone or combined with GBR allowed similar and limited bone gain.

Efectividad clínica y radiográfica de la pasta antibiótica CTZ en pulpotomías de molares primarios: ensayo clínico aleatorio controlado / Clinical and radiographic effectiveness of antibiotic paste CTZ in primary molars pulpotomy: ramdomized controlled clinical trial

El objetivo de este trabajo fue evaluar clínica y radiográficamente la efectividad de la pasta antibiótica CTZ en pulpotomías de molares primarios. Se realizó un ensayo clínico aleatorio controlado, en 40 molares primarios de 40 preescolares con edades entre 3 y 6 años. Los pacientes fueron seleccionados y asignados aleatoriamente a dos grupos: Formocresol (n=20), CTZ (Cloranfenicol-Tetraciclina-Oxido de Zinc Eugenol, n=20). Los dientes fueron restaurados con ionómero de vidrio y coronas metálicas de acero preformadas. La evaluación clínica y radiográfica fue realizada a los 3 y 6 meses. Se utilizó el programa SPSS v.17 para el análisis de los datos, y la aplicación del Test Exacto de Fisher al 5 %. El comportamiento clínico a los 3 meses mostró 75 % de éxito para los molares tratados con formocresol y 70 % para el CTZ. Radiográficamente se obtuvo 90 % de éxito para el grupo con formocresol y 100 % para la pasta CTZ. A los 6 meses el éxito clínico del formocresol fue de 85 % y del CTZ 80 %. El éxito radiográfico mostrado fue 65 % para los atendidos con formocresol y 80 % para el CTZ (p > 0,05). No se observaron diferencias significativas entre los grupos de tratamiento. La pasta CTZ es una alternativa en el tratamiento de pulpotomías de molares temporales. Ofrece un efecto antimicrobiano, estabilización del proceso de reabsorción radicular, sin ocasionar daños a la formación del diente permanente.

The objective of this study to evaluate the clinical and radiographic effectiveness of antibiotic paste CTZ in pulpotomy of primary molars. A randomized controlled clinical trial was performed, in 40 molars of 40 patients aged 3 to 6 years. Were selected and randomly assigned to two groups: Formocresol (n=20), CTZ (Chloramphenicol-Tetracycline-Zinc Oxide Eugenol, n=20). The teeth were restored with glass ionomer and performed steel metal crowns. Clinical and radiographic evaluation procedure was performed at 3 and 6 months. SPSS v.17 program for data analysis, and application of the Fisher exact test was used 5 %. The clinical behavior at 3 months showed 75 % success rate for molars treated with formocresol and 70 % for the CTZ. Radiographically 90 % success rate for the group with formocresol and 100 % for the CTZ paste was obtained. At 6 months formocresol clinical success was 85 % and 80 % CTZ. Radiographic success was shown 65 % for those treated with formocresol and 80 % for the CTZ (p>0.05). No significant differences in the results shown were observed. CTZ paste is an alternative in the treatment of pulpotomy of molars. It provides an antimicrobial effect, stabilizing the process of root resorption, without causing damage to the permanent tooth formation.

Immediate tooth replantation in rats: effect of systemic antibiotic therapy with amoxicillin and tetracycline.

OBJECTIVES: The aim of this study was to evaluate the influence of systemic administration of antibiotics (amoxicillin and tetracycline) at the different phases of the repair process (7, 15, 30 days) in immediate rat tooth replantation. MATERIALS AND METHODS: Ninety rats had their incisors extracted and stored in saline for 5 min. Next, the teeth were replanted, and the animals were assigned to three groups according to the antibiotic administered by oral gavage: control group, amoxycillin group, and tetracycline group. Euthanasia was performed at 7, 15, and 30 days after replantation. RESULTS: Regardless of the evaluation period, the connective tissue underlying the epithelial attachment and the periodontal ligament showed statistically significant difference relative to the acute inflammatory infiltrate, which was more intense in the control group followed by the tetracycline group. CONCLUSION: These results point to the fact that systemic antibiotic therapy (SAT) in immediate tooth replantation is beneficial to pulpal and periodontal ligament repair and that amoxycillin is an excellent option. CLINICAL RELEVANCE: There is a lack of randomized studies assessing how the use of systemic antibiotics could influence tooth healing after immediate replantation.

Resistance to B-lactam and tetracycline in Campylobacter spp isolated from broiler slaughterhouses in southern Brazil / Resistência a B-lactâmicos e tetraciclina em Campylobacter spp isolados de matadouros-frigoríficos de aves no sul do Brasil

The study was carried out to screen and analyze the genetic characteristics of antimicrobial resistance in Campylobacter spp. from poultry sources. A total of 141 strains of Campylobacter isolated from samples of broilers of slaughterhouses in southern Brazil was identified by phenotypic and genotypic methods. Campylobacter isolates were evaluated for its antimicrobial susceptibility and the presence of resistance genes. The strains were investigated for antimicrobial susceptibility against two agents (ampicillin and tetracycline) by disk diffusion method. PCR assay was used to confirm the specie and the presence of ampicillin (blaOXA-61), tetracycline tet(O), and the energy-dependent multi-drug efflux pump (cmeB) genes. Campylobacter jejuni was the most ubiquitous; its presence was determined in 140 samples out of 141 (99.3%), whereas Campylobacter coli was found only in one of the contaminated samples (0.70%). The results obtained showed 65% and 35.5% of Campylobacter isolates resistant to β-lactams and tetracyclines, respectively. The cmeB gene responsible for multidrug resistance was detected in 26 isolates out 141 strains (18.5%). Moreover, 36 out of 141 Campylobacter strains (25.6%) were found to be resistant to at least two different antimicrobia resistance markers (β-lactams and tetracyclines).(AU)

O presente estudo foi realizado para examinar e analisar as características genéticas de resistência antimicrobiana de Campylobacter spp. a partir de fontes avícolas. Um total de 141 amostras de Campylobacter isolados em matadouros-frigoríficos de aves do estado do Rio Grande do Sul, Brasil, foi identificado por métodos fenotípicos e genotípicos. Foi analisada a susceptibilidade antimicrobiana e a presença de genes de resistência. As cepas foram testadas para detectar sensibilidade frente a dois antimicrobianos (ampicilina e tetraciclina) pelo método de difusão em disco. A seguir, usando a reação em cadeia da polimerase foi confirmada a espécie e a presença dos genes de resistência à ampicilina (blaOXA-61) e tetraciclina tet(O), assim como a detecção da bomba de efluxo (cmeB). Campylobacter jejuni foi a espécie mais isolada, sua presença foi determinada em 140 amostras (99,3%), e Campylobacter coli foi encontrada em uma única amostra (0,70%). Os resultados obtidos mostraram 65% e 35,5% de Campylobacter isolados resistentes a β-lactâmicos e tetraciclinas, respectivamente. O gene cmeB responsável pela resistência a múltiplos antimicrobianos foi detectado em 26 amostras (18,5%). Neste contexto, 36 das 141 amostras (25,6%) foram consideradas resistentes a dois grupos diferentes de antimicrobianos (β-lactâmicos e tetraciclinas).(AU)

Resistance to B-lactam and tetracycline in Campylobacter spp isolated from broiler slaughterhouses in southern Brazil / Resistência a B-lactâmicos e tetraciclina em Campylobacter spp isolados de matadouros-frigoríficos de aves no sul do Brasil

The study was carried out to screen and analyze the genetic characteristics of antimicrobial resistance in Campylobacter spp. from poultry sources. A total of 141 strains of Campylobacter isolated from samples of broilers of slaughterhouses in southern Brazil was identified by phenotypic and genotypic methods. Campylobacter isolates were evaluated for its antimicrobial susceptibility and the presence of resistance genes. The strains were investigated for antimicrobial susceptibility against two agents (ampicillin and tetracycline) by disk diffusion method. PCR assay was used to confirm the specie and the presence of ampicillin (blaOXA-61), tetracycline tet(O), and the energy-dependent multi-drug efflux pump (cmeB) genes. Campylobacter jejuni was the most ubiquitous; its presence was determined in 140 samples out of 141 (99.3%), whereas Campylobacter coli was found only in one of the contaminated samples (0.70%). The results obtained showed 65% and 35.5% of Campylobacter isolates resistant to β-lactams and tetracyclines, respectively. The cmeB gene responsible for multidrug resistance was detected in 26 isolates out 141 strains (18.5%). Moreover, 36 out of 141 Campylobacter strains (25.6%) were found to be resistant to at least two different antimicrobia resistance markers (β-lactams and tetracyclines)...

O presente estudo foi realizado para examinar e analisar as características genéticas de resistência antimicrobiana de Campylobacter spp. a partir de fontes avícolas. Um total de 141 amostras de Campylobacter isolados em matadouros-frigoríficos de aves do estado do Rio Grande do Sul, Brasil, foi identificado por métodos fenotípicos e genotípicos. Foi analisada a susceptibilidade antimicrobiana e a presença de genes de resistência. As cepas foram testadas para detectar sensibilidade frente a dois antimicrobianos (ampicilina e tetraciclina) pelo método de difusão em disco. A seguir, usando a reação em cadeia da polimerase foi confirmada a espécie e a presença dos genes de resistência à ampicilina (blaOXA-61) e tetraciclina tet(O), assim como a detecção da bomba de efluxo (cmeB). Campylobacter jejuni foi a espécie mais isolada, sua presença foi determinada em 140 amostras (99,3%), e Campylobacter coli foi encontrada em uma única amostra (0,70%). Os resultados obtidos mostraram 65% e 35,5% de Campylobacter isolados resistentes a β-lactâmicos e tetraciclinas, respectivamente. O gene cmeB responsável pela resistência a múltiplos antimicrobianos foi detectado em 26 amostras (18,5%). Neste contexto, 36 das 141 amostras (25,6%) foram consideradas resistentes a dois grupos diferentes de antimicrobianos (β-lactâmicos e tetraciclinas)...

The Essential Oil from Origanum vulgare L. and Its Individual Constituents Carvacrol and Thymol Enhance the Effect of Tetracycline against Staphylococcus aureus.

BACKGROUND: In an ongoing project to evaluate essential oils as modulators of antibiotic resistance, the essential oil from Origanum vulgare L. (OVEO), as well as its individual constituents carvacrol (CAR) and thymol (THY), were investigated using Staphylococcus aureus strains possessing efflux mechanisms of resistance to norfloxacin, erythromycin and tetracycline. METHODS: The minimum inhibitory concentration (MIC) values of the antibiotics were determined by agar dilution method, in the absence and in the presence of subinhibitory concentrations of OVEO, CAR or THY. RESULTS: Along with relevant antistaphylococcal activity, OVEO, CAR and THY modulated the activity of tetracycline, i.e. in combination with antibiotics a reduction in the MIC was observed (up to fourfold). CONCLUSIONS: The results presented here represent, as far as we know, the first report of OVEO, CAR and THY as putative efflux pump inhibitors. Broadly, these findings indicate that essential oils could serve as potential sources of compounds capable of modulating drug resistance.

Wound healing of dehiscence defects following different root conditioning modalities: an experimental study in dogs.

OBJECTIVE: The purpose of this study was to investigate the periodontal healing pattern of dehiscence-type defects following different chemical root conditioning modalities. MATERIALS AND METHODS: Buccal osseous dehiscence defects were created on six teeth of seven dogs. After dental plaque accumulation, defects were treated with sterile saline solution (control group) or one chemical conditioning modality: citric acid (CA group), ethylenediaminetetraacetic acid (EDTA group), tetracycline (TTC group), citric acid + tetracycline (CA + TTC group), or tetracycline + citric acid (TTC + CA group). After 3 months of healing, clinical parameters were evaluated, and the animals were killed. Histological sections were processed, and a computer-assisted histometric analysis was used to evaluate the formation of new cementum, new bone, and epithelial apical migration. RESULTS: All treatments yielded significant improvements in terms of probing depth decrease and clinical attachment level gain compared to baseline values; however, without significant differences among the groups (p > 0.05; one-way ANOVA). The highest amount of new cementum was noted in the EDTA group (3.72 ± 0.83 mm, 77.6 %), while the lowest amount of new bone was observed in the TTC group (0.7 ± 0.94 mm, 14.3 %). However, no statistically significant differences could be observed among the groups regarding epithelial apical migration, new cementum, and alveolar bone formation (p > 0.05). CONCLUSION: Chemical root surface conditioning did not promote any significant improvement in periodontal healing pattern of dehiscence-type defects in dogs. CLINICAL RELEVANCE: Chemical root surface conditioning after surgical debridement did not promote positive or negative effects on periodontal healing pattern of dehiscence-type defects.

Laminados cerâmicos para resolução estética de dentes manchados por tetraciclina / Ceramic laminates for aesthetic resolution of tetracycline spotted teeth

O escurecimento dental de origem medicamentosa pela ingestão da tetraciclina repercute negativamente na aparência do sorriso. A tetraciclina quando utilizada no período em que os dentes estão sendo formados pode induzir a formação de manchas de coloração amarelada ou marrom-acinzentada na estrutura dentária. Seu uso quando os dentes já estão formados ou erupcionados na cavidade bucal não provoca alterações perceptíveis nos elementos dentários. Os tratamentos indicados para essa ocorrência contemplam a microabrasão, clareamento e laminados. Este trabalho teve como objetivo apresentar os cuidados para o planejamento estético em casos de manchamentos dentários por tetraciclina, e a descrição clínica para execução de laminados cerâmicos confeccionados em IPS E-max (Ivoclar - Vivadent). A harmonia e estética obtidas na conclusão do caso traduzem a saúde e conforto devolvidos ao paciente para o tratamento proposto

The darkening of teeth caused by tetracycline ingestion affects the appearance of the smile in an undesirable way. When used during teeth formation period tetracycline can induce the appearance of yellow or grayish-brown stains in the dental structure. Its use does not cause noticeable changes in the teeth when the teeth are already formed or erupted in the oral cavity. In these cases recommended treatments includes micro abrasion, tooth whitening and ceramic veneers. This paper aimed at presenting aspects that must be observed on aesthetic planning on cases of dental staining caused by tetracycline, as well as describe clinical steps for the execution of ceramic laminates produced using IPS E-max (Ivoclar -Vivadent). Harmony and aesthetics results obtained after the treatment are reflected on the restoration of patient’s health and comfort

Carriage of antibiotic-resistant Escherichia coli among healthy children and home-raised chickens: a household study in a resource-limited setting.

We have previously observed high rates of acquired antibiotic resistance in commensal Escherichia coli from healthy children living in urban areas of Bolivia and Peru, including resistance to tetracycline and quinolones, which are not routinely used in childhood. In this work we investigated acquired resistance in commensal E. coli from healthy children and home-raised chickens in 12 households from one of the previously surveyed urban area in Bolivia, to ascertain the possibility of human-animal exchange of resistant strains in similar settings. The resistance rates to ampicillin, tetracycline, chloramphenicol, streptomycin, and trimethoprim-sulphametoxazole were overall high (≥50%) and comparable between children and chickens, whereas those to quinolones were significantly higher in chickens (81% vs. 29% for nalidixic acid; 43% vs. 10% for ciprofloxacin). Molecular characterization of tetracycline- and quinolone-resistant isolates (n = 66) from children and chickens of three selected households revealed a remarkable clonal diversity and, in some cases, the presence of the same resistant strains among children or among chickens living in the same household, but not between children and chickens. Several resistance plasmids were characterized, but inter-clonal plasmid dissemination was not detected. Overall, the results from the present study suggested that cross-transmission between children and home-raised chickens could not represent a major spreading mechanism for resistant E. coli in households of resource-limited settings with high human-animal promiscuity.

Effect of zein on biodegradable inserts for the delivery of tetracycline within periodontal pockets.

Treatment with antibiotics within the periodontal pocket against bacterial infections represents a useful and adjunctive tool to conventional therapy for healing and teeth preservation. With this function in view, an implantable, tetracycline delivery device for the treatment of periodontal disease was developed. The aim of this study was to develop biodegradable, tetracycline-loaded microparticles made of two polymers: PLGA and zein which were compressed into monolithic devices. In this polymer delivery system, the encapsulation efficiency, release characteristics, drug-polymer interaction, and antibacterial activity of loaded drug were investigated. The interaction of tetracycline with the corn protein zein was studied by nuclear magnetic resonance (NMR), Fourier transform infrared, and X-ray diffraction. The hydrophobic interaction of tetracycline with zein in the formulations was deduced from the NMR studies, whereas X-ray diffraction studies showed a new crystalline state of the drug in the presence of the protein. Zein was not denatured by preparation of inserts. Sustained release of tetracycline was obtained, and the proportion of zein in the inserts had a great impact on the drug release. Finally, an effective tetracycline release from inserts against Staphylococcus aureus was achieved over 30 days. In conclusion, the PLGA:zein delivery system described in this study was found to be effective in controlled delivery of tetracycline, and hence may be suitable for intra-pocket delivery of antimicrobial agents in the treatment of periodontitis.

Modulation of cytokine and cytokine receptor/antagonist by treatment with doxycycline and tetracycline in patients with dengue fever.

Dengue virus infection can lead to dengue fever (DF) or dengue hemorrhagic fever (DHF). Disease severity has been linked to an increase in various cytokine levels. In this study, we evaluated the effectiveness of doxycycline and tetracycline to modulate serum levels of IL-6, IL-1B, and TNF and cytokine receptor/receptor antagonist TNF-R1 and IL-1RA in patients with DF or DHF. Hospitalized patients were randomized to receive standard supportive care or supportive care combined with doxycycline or tetracycline therapy. Serum cytokine and cytokine receptor/antagonist levels were determined at the onset of therapy and after 3 and 7 days. Cytokine and cytokine receptor/antagonist levels were substantially elevated at day 0. IL-6, IL-1ß, and TNF remained at or above day 0 levels throughout the study period in untreated patients. Treatment with tetracycline or doxycycline resulted in a significant decline in cytokine levels. Similarly, IL-1RA and TNF-R1 serum concentrations were elevated at baseline and showed a moderate increase among untreated patients. Both drugs resulted in a significant rise in IL-1Ra levels by day 3 in patients. In contrast, treatment did not affect a similar result for TNF-R1. When compared to the control group, however, a significant rise post-treatment was seen upon intragroup analysis. Further analysis demonstrated that doxycycline was significantly more effective at modulating cytokine and cytokine receptor/antagonist levels than tetracycline.

Release of tetracycline from O-carboxymethylchitosan films.

O-carboxymethylchitosan films containing tetracycline were prepared by the casting method. The films were hardened by reaction with glutaraldehyde-induced crosslinking and heat treatment at 90°C, 120°C and 150°C. The effect, on the films, of hardening methods, water uptake, moisture, drug release and antimicrobial activity against Staphylococcus aureus was evaluated. The O-carboxymethylchitosan films were soluble in simulated saliva and after treatment, and the water uptake of the films decreased as the temperature or presence of glutaraldehyde increased. The antimicrobial activity of tetracycline was preserved, and efficiency was dependent on the hardening treatment to which the films were submitted.

Histomorphometric changes in the testes and epididymis of wistar strain albino rats following fourteen days oral administration of therapeutic doses of some antibiotics / Cambios histomorfométricos en los testículos y el epidídimo de ratas cepa wistar albinas después de catorce días de administración oral de dosis terapéuticas de algunos antiobióticos

Studies on testes and epididymis tissue of rats treated orally for fourteen days with therapeutic doses of cloxacillin (6mg/100g/day), ampicillin (4mg/100/day) and tetracycline (12mg/100g/day) separately showed a significant reduction in testicular and epididimis architecture. Microscopic studies of these male reproductive organs further revealed a significant alteration in the epididymis as revealed by a significant reduction (p<0.05) in epididymal ductular diameter (EDD), and epididymal epithelial height (EEH) in treated group of animals. A significant increase (p<0.05) was however recorded in epididymal luminal diameter (ELD) in all the animals after the two and three week's recovery period allowed. This gives another insight into the toxicity activities of these antibiotics on male reproductive organs, apart from reduction in serum testosterone level, decreased sperm motility, decreased spermatozoa count and decrease in RNA and DNA content of spermatogenic cells as earlier reported.

Estudios referentes a testículos y tejido epididimario en ratas tratadas por vía oral durante catorce días, con dosis terapéuticas de cloxacilina (6mg/100g/día), ampicilina (4mg/100/día) y tetraciclina (12mg/100g/día) por separado muestran una reducción significativa en el peso testicular y epidídimario. Los estudios microscópicos de los órganos reproductores masculinos revelan además una alteración significativa en el epidídimo como se observa en la reducción del diámetro (p<0,05) de los conductos del epidídimo (EDD), y la altura del epitelio epididimal (EEH) en el grupo de los animales tratados. Sin embargo, se registró un aumento significativo (p <0,05) en el diámetro luminal del epidídimo (ELD) en todos los animales después de dos y tres semanas del período de recuperación. Esto genera otro punto de vista en relación a la toxicidad de estos antibióticos en los órganos reproductivos masculinos, además de la reducción de la concentración sérica de testosterona, disminución de la motilidad del esperma, disminución del recuento de espermatozoides y disminución en el contenido de ARN y ADN en las células de espermatogénesis como se reportó anteriormente.

[Oleoma: A case report with good response to tetracycline]. / Oleoma: Relato de caso com boa resposta à tetraciclina.

Oleoma or paraffinoma is defined as a foreign body granuloma that results from the injection of oily substances into the skin or subcutaneous tissue. We present a young patient with ulcerated lesions secondary to infiltration of oily material. He had undergone the injections with the aim of increasing muscle mass and definition. The treatment of these cases is quite complex, often with unsatisfactory results. The use of long-term oral tetracycline proved to be helpful.

Early antimicrobial activity of intracanal medications on the external root surface of periodontally compromised teeth.

OBJECTIVE: To verify the effect of scaling and root planing on the antimicrobial activity of intracanal medications on the external root surface of periodontally compromised teeth. METHOD AND MATERIALS: Forty single-rooted extracted teeth were randomly assigned for visible calculus removal or scaling and root planing. Samples were separated into four groups-chlorhexidine, tetracycline hydrochloride, calcium hydroxide, or saline solution-and immersed in semisolid media and seeded with Micrococcus luteus for 24 hours. The zones of inhibition were measured using a profile projector. RESULTS: Calcium hydroxide and saline solution did not show bacterial growth inhibition. Chlorhexidine and tetracycline showed the occurrence of zones of inhibition in 70% and 40% of specimens, respectively. CONCLUSION: Partial antimicrobial activity on the external root surface was found when chlorhexidine and tetracycline solutions were used as intracanal medications; however, root planing procedures may modify this condition.