RESUMEN
Implant born prosthetic rehabilitation of tumour patients can be difficult to perform. Challenges in treating such patients include disrupted anatomy with limited mouth opening due to previous ablative surgery as well as free-flaps or simple bone grafts, adjuvant therapy such as radiotherapy and, in general, poorer general health. Combining classical knowledge of ideal prosthesis placement and current virtual planning possibilities the positioning and in consequence the survival of dental implants can be optimised. Since prosthetic rehabilitation has a positive effect on the patients' quality of life and general health, we propose performing such surgeries as early as possible. All patients at our institution receiving pre-planned guided implant reconstruction and postoperative evaluation with Cone Beam Computed Tomography (CBCT) between 2015 and 2018 were evaluated for inclusion. Eight patients with a total of 30 implants met the inclusion criteria. The planned implant position was compared to the outcome position by fusing the two and deviations in entry-point position, apex-position, angular deviation and depth error were recorded. The mean (SD) discrepancy at entry-point was 2.28 (1.45) mm and 2.89 (1.53) mm at the apex, respectively. Mean (SD) angulation discrepancy was 9.5Ë (4.13Ë) and the mean (SD) depth deviation was 1.52 (0.86) mm. Our results demonstrate the feasibility of pre-planned implant placement in challenging clinical situations and that only few concessions have to be made for precision.
Asunto(s)
Implantes Dentales , Neoplasias , Cirugía Asistida por Computador , Diseño Asistido por Computadora , Tomografía Computarizada de Haz Cónico , Implantación Dental Endoósea , Humanos , Planificación de Atención al Paciente , Calidad de VidaRESUMEN
The Surgical reconstruction of defects of the face is challenging. Local and regional flaps have an important part to play, but large defects of bone and soft tissue are a greater problem. Microvascular tissue transfer has become the standard for such patients, and preoperative planning of bony reconstructions is now common. To use these preplanning tools best the implants should be placed in the prosthetically ideal place, and the bone positioned to surround the implants - that is, truly backward planning of the position of the bone. The buccolingual angulation and the actual position of the implants during operation can be difficult to verify. Using commonly available software and 3-dimensional printing solutions, therefore, we have constructed an algorithm to optimise the position of these implants during the operation, and to get their position as close to the planned outcome as possible. This algorithm is adaptable to any implant system and is potentially possible in any implant or preplanning software unit.
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Aumento de la Cresta Alveolar/métodos , Trasplante Óseo/métodos , Diseño Asistido por Computadora , Peroné/trasplante , Colgajos Tisulares Libres , Carga Inmediata del Implante Dental , Reconstrucción Mandibular/métodos , Cirugía Asistida por Computador/métodos , Flujo de Trabajo , Algoritmos , Femenino , Humanos , Imagenología Tridimensional/métodos , Masculino , Diseño de Prótesis , Radiografía Panorámica , Tomografía Computarizada por Rayos XRESUMEN
Rehabilitation with implant-retained prostheses is a key step in the rehabilitation of patients after ablative head and neck surgery. Data of patients who underwent mandibular restoration with Astra Tech implants were gathered consecutively and analyzed retrospectively. Implant survival was calculated by Kaplan-Meier analysis, and Cox models were used to identify any association between implant failure and contributing factors. In total, 136 implants were placed in 33 patients. The main reason for ablative surgery was squamous cell carcinoma. Twenty-one patients received adjuvant radiotherapy with a cumulative radiation dose of 56-76Gy prior to implantation. Failure occurred in six patients, resulting in the loss of 17 implants. The cumulative implant survival rate was 92.7% after 1 year and 87.5% after 20 months. Smoking and alcohol consumption were associated with a significantly higher implant failure rate. Most patients had a stable implant status after 20 months.
Asunto(s)
Carcinoma de Células Escamosas/cirugía , Prótesis Dental de Soporte Implantado , Neoplasias de Cabeza y Cuello/cirugía , Anciano , Consumo de Bebidas Alcohólicas/efectos adversos , Carcinoma de Células Escamosas/radioterapia , Implantes Dentales , Diseño de Prótesis Dental , Fracaso de la Restauración Dental , Femenino , Neoplasias de Cabeza y Cuello/radioterapia , Humanos , Masculino , Mandíbula/efectos de la radiación , Mandíbula/cirugía , Persona de Mediana Edad , Dosificación Radioterapéutica , Radioterapia Adyuvante , Estudios Retrospectivos , Factores de Riesgo , Fumar/efectos adversos , Colgajos Quirúrgicos , Tasa de Supervivencia , Resultado del TratamientoRESUMEN
The objective of this study was to investigate clinical signs indicating hereditary diseases like equine sarcoid, osteochondrosis (OC) and the idiopathic laryngeal hemiplegia (ILH), and to demonstrate relationships between environment, feeding habits and conformation ("exterieur" evaluation) of the horses. For this purpose, we analyzed veterinary examinations of 403 stallions at the approvals since 1994 examined 493 three-year-old Swiss Warmblood horses, which were shown at the Swiss-Field-Tests in 2005. With the help of the owners a questionnaire on health, environment and feeding habits of the animals was completed. At the same time, the horses were assessed and graded for their "exterieur" (type, conformation, gaits) by judges of the Swiss Sporthorse breeding association. In 11.5% of horses sarcoids were found, 8.7% showed one and 2.8% several tumors. The prevalence of sarcoids in offspring of sires with known sarcoids was not significantly higher than in descendants from stallions without a known history of sarcoids. We found distended joints as a possible symptom of OC in 11.4% of the horses, 3.9% (n = 19) in both tarsal joints. We did not find a relationship between enlarged joints in the offspring and the presence of OC in the sires. Abnormal respiratory noise at work, as a possible sign for ILH, was heard only in 1.2% (n = 6). It is important to note that while we found a high number of sarcoid affected horses compared to other studies, presence of enlarged joints was not very frequent and very few horses showed abnormal respiratory noise. Additionally, we found no correlation between "exterieur" marks and the horse's general health.
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Enfermedades de los Caballos/epidemiología , Enfermedades de los Caballos/genética , Linaje , Animales , Femenino , Predisposición Genética a la Enfermedad , Caballos , Masculino , Osteocondritis/epidemiología , Osteocondritis/genética , Osteocondritis/veterinaria , Prevalencia , Neoplasias Cutáneas/epidemiología , Neoplasias Cutáneas/genética , Neoplasias Cutáneas/veterinaria , Suiza/epidemiologíaRESUMEN
Long time series of ground-based plant phenology, as well as more than two decades of satellite-derived phenological metrics, are currently available to assess the impacts of climate variability and trends on terrestrial vegetation. Traditional plant phenology provides very accurate information on individual plant species, but with limited spatial coverage. Satellite phenology allows monitoring of terrestrial vegetation on a global scale and provides an integrative view at the landscape level. Linking the strengths of both methodologies has high potential value for climate impact studies. We compared a multispecies index from ground-observed spring phases with two types (maximum slope and threshold approach) of satellite-derived start-of-season (SOS) metrics. We focus on Switzerland from 1982 to 2001 and show that temporal and spatial variability of the multispecies index correspond well with the satellite-derived metrics. All phenological metrics correlate with temperature anomalies as expected. The slope approach proved to deviate strongly from the temporal development of the ground observations as well as from the threshold-defined SOS satellite measure. The slope spring indicator is considered to indicate a different stage in vegetation development and is therefore less suited as a SOS parameter for comparative studies in relation to ground-observed phenology. Satellite-derived metrics are, however, very susceptible to snow cover, and it is suggested that this snow cover should be better accounted for by the use of newer satellite sensors.
Asunto(s)
Clima , Ecología/métodos , Ecosistema , Desarrollo de la Planta , Bases de Datos Factuales , Efecto Invernadero , Estaciones del Año , Nave Espacial , Tiempo (Meteorología)RESUMEN
Lung transplant recipients have one of the highest rates of invasive aspergillosis (IA) in solid organ transplantation. We used a single center, nonrandomized, retrospective, sequential study design to evaluate fungal infection rates in lung transplant recipients who were managed with either universal prophylaxis with voriconazole (n = 65) or targeted prophylaxis (n = 30) with itraconazole +/- inhaled amphotericin in patients at high risk (pre- or posttransplant Aspergillus colonization [except Aspergillus niger]). The rate of IA at 1 year was better in lung transplant recipients receiving voriconazole prophylaxis as compared to the cohort managed with targeted prophylaxis (1.5% vs. 23%; p = 0.001). Twenty-nine percent of cases in the targeted prophylaxis group were in patients colonized with A. niger who did not receive itraconazole. A three-fold or higher increase in liver enzymes was noted in 37-60% of patients receiving voriconazole prophylaxis as compared to 15-41% of patients in the targeted prophylaxis cohort. Fourteen percent in the voriconazole group as compared to 8% in the targeted prophylaxis group had to discontinue antifungal medications due to side effects. Voriconazole prophylaxis can be used in preventing IA in lung transplant recipients. Regular monitoring of liver enzymes and serum concentrations of calcineurin inhibitors are required to avoid hepatotoxicity and nephrotoxicity.
Asunto(s)
Antifúngicos/uso terapéutico , Trasplante de Pulmón/fisiología , Micosis/prevención & control , Pirimidinas/uso terapéutico , Triazoles/uso terapéutico , Aspergilosis/tratamiento farmacológico , Aspergilosis/epidemiología , Quimioprevención , Femenino , Humanos , Trasplante de Pulmón/efectos adversos , Trasplante de Pulmón/mortalidad , Masculino , Persona de Mediana Edad , Micosis/epidemiología , Complicaciones Posoperatorias/epidemiología , Complicaciones Posoperatorias/microbiología , Complicaciones Posoperatorias/prevención & control , Probabilidad , Estudios Retrospectivos , Análisis de Supervivencia , Factores de Tiempo , VoriconazolRESUMEN
UNLABELLED: The complement activation demonstrated by vascular C4d deposition is used to diagnose antibody-mediated rejection (AMR) in renal allografts, but remains controversial in lung transplantation (LTX). METHODS: C4d deposition was assessed by immunohistochemistry in 192 lung transplant biopsies from 32 patients. ELISA analysis was performed on 415 serum samples in those 32 temporally and rejection-grade matched LTX patients; 16 patients developed HLA-Ab, while the other 16 patients remained negative. The specificity of C4d staining was further compared in 18 additional LTX patients without HLA-Ab or acute cellular rejection (ACR), but in the presence of CMV-pneumonitis or reperfusion injury. RESULTS: Specific subendothelial C4d deposition was seen in 5 of 16 (31%) patients with HLA-Ab and was absent in 16 patients without HLA-Ab (p<0.05). All patients with specific C4d deposition exhibited donor-specific HLA-Ab. There were 13 patients with bronchiolitis obliterans syndrome in the group of 16 HLA-Ab positive patients, versus 2/16 in ELISA-negative patients (p<0.005). One of 7 patients with CMV pneumonitis and 2 of 11 patients with reperfusion injury also showed C4d positivity (not statistically significant). CONCLUSIONS: In this study, specific subendothelial C4d deposition was a marker for the involvement of HLA-Ab in lung allograft rejection. The patchy nature, low sensitivity, and specificity of C4d staining might limit clinical use in protocol biopsies. However, in patients with decreasing pulmonary function, refractory ACR and/or HLA-Ab, specific C4d deposition may serve as a marker of coexistent AMR.
Asunto(s)
Complemento C4b/análisis , Rechazo de Injerto/diagnóstico , Antígenos HLA/inmunología , Isoanticuerpos/sangre , Trasplante de Pulmón/inmunología , Pulmón/inmunología , Fragmentos de Péptidos/análisis , Enfermedad Aguda , Rechazo de Injerto/inmunología , HumanosRESUMEN
The success of lung transplantation has improved over time as evidenced by better long-term survival and functional outcomes. Despite the success of this procedure, there are numerous problems and complications that may develop over the life of a lung transplant recipient. With proper monitoring and treatment, the frequency and severity of these problems can be decreased. However, significant improvement for the overall outcomes of lung transplantation will only occur when better methods exist to prevent or effectively treat chronic rejection.
Asunto(s)
Trasplante de Pulmón , Análisis Costo-Beneficio , Supervivencia de Injerto , Humanos , Calidad de Vida , Análisis de Supervivencia , Resultado del TratamientoRESUMEN
BACKGROUND: Obliterative bronchiolitis (OB) remains one of the leading causes of death in lung transplant recipients after 2 years, and acute rejection (AR) of lung allograft is a major risk factor for OB. Treatment of AR may reduce the incidence of OB, although diagnosis of AR often requires bronchoscopic lung biopsy. In this study, we evaluated the utility of exhaled-breath biomarkers for the non-invasive diagnosis of AR. METHODS: We obtained breath samples from 44 consecutive lung transplant recipients who attended ambulatory follow-up visits for the Johns Hopkins Lung Transplant Program. Bronchoscopy within 7 days of their breath samples showed histopathology in 21 of these patients, and we included them in our analysis. We measured hydrocarbon markers of pro-oxidant events (ethane and 1-pentane), isoprene, acetone, and sulfur-containing compounds (hydrogen sulfide and carbonyl sulfide) in exhaled breath and compared their levels to the lung histopathology, graded as stable (non-rejection) or AR. None of the study subjects were diagnosed with OB or infection at the time of the clinical bronchoscopy. RESULTS: We found no significant difference in exhaled levels of hydrocarbons, acetone, or hydrogen sulfide between the stable and AR groups. However, we did find significant increase in exhaled carbonyl sulfide (COS) levels in AR subjects compared with stable subjects. We also observed a trend in 7 of 8 patients who had serial sets of breath and histopathology data that supported a role for COS as a breath biomarker of AR. CONCLUSIONS: This study demonstrated elevations in exhaled COS levels in subjects with AR compared with stable subjects, suggesting a diagnostic role for this non-invasive biomarker. Further exploration of breath analysis in lung transplant recipients is warranted to complement fiberoptic bronchoscopy and obviate the need for this procedure in some patients.
Asunto(s)
Biomarcadores/análisis , Hemiterpenos , Trasplante de Pulmón , Acetona/análisis , Adulto , Anciano , Pruebas Respiratorias , Butadienos/análisis , Etano/análisis , Femenino , Estudios de Seguimiento , Rechazo de Injerto , Humanos , Sulfuro de Hidrógeno/análisis , Masculino , Persona de Mediana Edad , Pentanos/análisis , Óxidos de Azufre/análisis , Trasplante HomólogoRESUMEN
Rhizobia are the only bacteria known to induce a multitude of small heat shock proteins (sHsps) upon temperature upshift. The sHsps of Bradyrhizobium japonicum fall into two different classes, class A and class B. Here, we studied the chaperone activity and oligomeric features of two representative members of each class. The purified sHsps were efficient chaperones, as demonstrated by their ability to prevent thermally induced aggregation of citrate synthase in vitro. Homo-oligomer formation of all four sHsps was demonstrated by gel filtration and by two independent co-purification approaches. Mixed oligomers were readily observed between members of the same class, even when these proteins originated from different species such as Escherichia coli and B. japonicum. The chaperone activity of purified hetero-oligomers was indistinguishable from the activity of homo-oligomers. Heteromeric complexes were never obtained between class A and class B sHsps, indicating that hetero-oligomer formation is restricted to sHsps of the same class.
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Bradyrhizobium/metabolismo , Proteínas de Escherichia coli , Proteínas de Choque Térmico/metabolismo , Chaperonas Moleculares/metabolismo , Cromatografía en Gel , Electroforesis en Gel de Poliacrilamida , Escherichia coli , Proteínas de Choque Térmico/aislamiento & purificación , Cuerpos de Inclusión/metabolismo , PolímerosRESUMEN
The aim of the present study was to assess the clinical behaviour of cast gold restorations with respect to define a gold control against current and future ceramic and composite restorations. The study sample included 50 patients with 303 cast gold restorations. All restorations were cemented with a non-adhesive technique. A total of 303 restorations were evaluated clinically and radiographically using modified United States Public Health Service criteria. Restorations recorded as having an A- or a B-rating were defined as successful. Of the 303 restorations, 42 were judged as failures, which resulted in a failure rate of 13.8% for a mean observation time (+/- s.d.) of 18.7 ( +/- 9.5) years. The estimated Kaplan-Meier survival rates (s.e.) were 96.1% (+/- 1.1%) at 10 years, 87.0% (+/- 2.2%) at 20 years and 73.5% (+/- 5.4%) at 30 years. In total, biological reasons were counted 25 times in comparison to 17 technical reasons for those 42 failed cast gold restorations, with 17 secondary caries (40%) as the most common biological reason and with 13 retention losses (31%) as the most common technical reason. The endodontically treated tooth was exclusively identified as a risk factor. The restoration type (inlay versus onlay) did not influence the survival rate.
Asunto(s)
Fracaso de la Restauración Dental , Aleaciones de Oro/uso terapéutico , Incrustaciones/estadística & datos numéricos , Intervalos de Confianza , Técnica de Colado Dental , Estudios de Seguimiento , Humanos , Modelos de Riesgos Proporcionales , Análisis de Supervivencia , Factores de Tiempo , Resultado del TratamientoRESUMEN
STATEMENT OF PROBLEM: Various augmentation procedures are recommended for the correction of localized alveolar ridge defects. However, no study has quantitatively evaluated the results of these procedures to date. PURPOSE: This study compared 2 soft tissue augmentation surgeries commonly used to alter contours of single-tooth pontic space by quantifying 3-dimensional volume changes with the optical projection Moiré method at 1 and 3.5 months after surgery. MATERIAL AND METHODS: Twenty-four patients required surgery. Each patient had a localized alveolar ridge defect, corresponding to a mesial-distal width of 1 single tooth. The defect of 12 patients was corrected with a subepithelial connective tissue graft; the remaining 12 patients were treated by receiving a free full-thickness gingival graft, which included epithelium and connective tissue with fatty tissue. Six unoperated defects of 6 patients formed the control group. For each defect, an impression was made before treatment, at 1 and 3.5 months after surgery to measure the volume changes on the dental casts with a validated projection Moiré system. Volume change was assessed relative to the preoperative dimension at the buccal and crestal aspects of the single-tooth pontic space. RESULTS: At 3.5 months postsurgery, mean volumetric gain for the connective tissue group with 159 mm(3) (SD +/- 80) was significantly greater (P =.027) than for free full-thickness gingival graft group with 104 mm(3) (SD +/- 31). CONCLUSION: The applied projection Moiré method proved its applicability in assessing 3-dimensional volume changes of pontic spaces with a single-tooth width. Volumetric assessment after 1 and 3.5 months revealed significantly greater volume gain with the subepithelial connective tissue graft in comparison to the free full-thickness gingival graft.
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Encía/anatomía & histología , Gingivoplastia/métodos , Tejido Adiposo/trasplante , Aumento de la Cresta Alveolar , Análisis de Varianza , Tejido Conectivo/trasplante , Pilares Dentales , Epitelio/trasplante , Estudios de Seguimiento , Encía/trasplante , Humanos , Procesamiento de Imagen Asistido por Computador , Modelos Dentales , Topografía de Moiré , Estudios Prospectivos , Reproducibilidad de los Resultados , Estadísticas no Paramétricas , Grabación en VideoRESUMEN
Small artery occlusive disease (microangiopathy) of the palm and digital arteries may produce ischemia with painful ulcerations on the digits. These ulcerations may contribute to secondary infection and severe intolerance to thermal changes. The use of gauze wrappings to minimize ulceration has been tried; however, it is unhygienic and unsightly. A custom-made digit prosthesis is constructed with medical grade silicone over an artificial finger nail to provide positive seating of the prosthesis. The digit prosthesis is hygienic, esthetically acceptable to the patient and greatly protects ulcerated finger tips.
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Arteriopatías Oclusivas/terapia , Dedos , Enfermedades Vasculares Periféricas/terapia , Prótesis e Implantes , Diseño de Prótesis , Vendajes/efectos adversos , Materiales Biocompatibles , Dimetilpolisiloxanos , Estética , Dedos/irrigación sanguínea , Humanos , Isquemia/terapia , Uñas , Coloración de Prótesis , Elastómeros de Silicona , Úlcera Cutánea/terapiaRESUMEN
Pseudomonas sp. strain B13 carries the clcRABDE genes encoding chlorocatechol-degradative enzymes on the self-transmissible 105-kb clc element. The element integrates site and orientation specifically into the chromosomes of various bacterial recipients, with a glycine tRNA structural gene (glyV) as the integration site. We report here the localization and nucleotide sequence of the integrase gene and the activity of the integrase gene product in mediating site-specific integration. The integrase gene (int-B13) was located near the right end of the clc element. It consisted of an open reading frame (ORF) of maximally 1,971 bp with a coding capacity for 657 amino acids (aa). The full-length protein (74 kDa) was observed upon overexpression and sodium dodecyl sulfate-polyacrylamide gel electrophoresis separation. The N-terminal 430 aa of the predicted Int-B13 protein had substantial similarity to integrases from bacteriophages of the P4 family, but Int-B13 was much larger than P4-type integrases. The C-terminal 220 aa of Int-B13 were homologous to an ORF flanking a gene cluster for naphthalene degradation in Pseudomonas aeruginosa PaK1. Similar to the bacteriophages phiR73 and P4, the clc element integrates into the 3' end of the target tRNA gene. This target site was characterized from four different recipient strains into which the clc element integrated, showing sequence specificity of the integration. In Pseudomonas sp. strain B13, a circular form of the clc element, which carries an 18-bp DNA sequence identical to the 3'-end portion of glyV as part of its attachment site (attP), could be detected. Upon chromosomal integration of the clc element into a bacterial attachment site (attB), a functional glyV was reconstructed at the right end of the element. The integration process could be demonstrated in RecA-deficient Escherichia coli with two recombinant plasmids, one carrying the int-B13 gene and the attP site and the other carrying the attB site of Pseudomonas putida F1.
Asunto(s)
Cromosomas Bacterianos , ADN Nucleotidiltransferasas/genética , Elementos Transponibles de ADN , Fagos Pseudomonas/genética , Pseudomonas putida/genética , Secuencia de Aminoácidos , Secuencia de Bases , Sitios de Unión , ADN Bacteriano , Escherichia coli/genética , Integrasas/genética , Datos de Secuencia Molecular , Pseudomonas putida/virología , Recombinasas , Homología de Secuencia de Aminoácido , Integración ViralRESUMEN
The survival rate and the reasons for failures of 130 combined fixed-removable reconstructions (CFR), incorporated in 112 patients, were assessed. Each CFR reconstruction was classified depending on its attachments: 76 reconstructions were attached with rigid, precise attachments, and constituted the rigid group; 54 reconstructions were attached with either semi-precision or individual attachments and were defined as the semi-rigid group. Of the 130 reconstructions, 41 were determined as complete successes, 39 as partial successes and 50 as failures, leading to 37 major repairs and to 13 new reconstructions. Three reconstructions failed due to technical reasons, 36 due to biological reasons and for 11 reconstructions, both categories of reasons were responsible for their failure. In total, technical reasons were counted 15 times in comparison to 73 biological reasons for those 50 failed reconstruction, with 29 fractured abutment teeth as the most common biological reason. Within the rigid group, 45 failed reconstructions were observed, whereas within the semi rigid group only 5 failures occurred, leading to an 8-year survival estimate (+/- SD) of 30.1% (+/- 6.9%) for the rigid group and 93.1% (+/- 3.9%) for the semi rigid group. Beside the attachment type, the anatomy of the partially edentulous tooth arch in form of the free-end situation and the dentate opposing jaw were identified as risk factors.
Asunto(s)
Fracaso de la Restauración Dental , Retención de Dentadura/instrumentación , Dentadura Parcial Fija , Dentadura Parcial Removible , Adulto , Anciano , Anciano de 80 o más Años , Abrazadera Dental , Diseño de Dentadura , Ajuste de Precisión de Prótesis , Análisis de Falla de Equipo , Femenino , Humanos , Arcada Parcialmente Edéntula/patología , Masculino , Persona de Mediana Edad , Modelos de Riesgos Proporcionales , Análisis de Regresión , Estudios Retrospectivos , Factores de Riesgo , Análisis de SupervivenciaRESUMEN
Analysis of chlorobenzene-degrading transconjugants of Pseudomonas putida F1 which had acquired the genes for chlorocatechol degradation (clc) from Pseudomonas sp. strain B13 revealed that the clc gene cluster was present on a 105-kb amplifiable genetic element (named the clc element). In one such transconjugant, P. putida RR22, a total of seven or eight chromosomal copies of the entire genetic element were present when the strain was cultivated on chlorobenzene. Chromosomal integrations of the 105-kb clc element occurred in two different loci, and the target sites were located within the 3' end of glycine tRNA structural genes. Tandem amplification of the clc element was preferentially detected in one locus on the F1 chromosome. After prolonged growth on nonselective medium, transconjugant strain RR22 gradually diverged into subpopulations with lower copy numbers of the clc element. Two nonadjacent copies of the clc element in different loci always remained after deamplification, but strains with only two copies could no longer use chlorobenzene as a sole substrate. This result suggests that the presence of multiple copies of the clc gene cluster was a prerequisite for the growth of P. putida RR22 on chlorobenzene and that amplification of the element was positively selected for in the presence of chlorobenzene.
Asunto(s)
Clorobenzoatos/metabolismo , Cromosomas Bacterianos , Amplificación de Genes , Pseudomonas putida/genética , Secuencia de Bases , Biodegradación Ambiental , Conjugación Genética , Cósmidos , Medios de Cultivo , Electroforesis en Gel de Campo Pulsado , Datos de Secuencia Molecular , Hibridación de Ácido Nucleico , Pseudomonas putida/crecimiento & desarrollo , Pseudomonas putida/metabolismo , Mapeo RestrictivoRESUMEN
The purpose of this research was to study the validity and variability of a projection Moiré system, measuring volume differences of geometrically different formed specimens mimicking localized alveolar ridge defects. Nine pairs of specimens were fabricated, each of which simulated a preoperative ridge defect and a corresponding surgically-corrected postoperative ridge defect. All specimen pairs had a mathematically defined form which allowed the accurate assessment of their volume differences by a mechanical 3-D coordinate measuring machine or by a software-controlled milling machine. Measurements achieved with these methods were used as the references for comparison. Six specimen pairs, A1 to A6, possessed a simple rectangular geometrical form which facilitated their fabrication. Three specimen pairs, B1 to B3, were milled and consisted of geometrically more complex 3-D sculptured surfaces, which came closest to a true imitation of a localized ridge defect. An optical measurement system in the form of the projection Moiré was utilized, applying a 4-phase shift technique, and results obtained with this device were regarded as test volumes. The absolute variability of the test volume measurements differed between 0.397 mm3 to 15.872 mm3, corresponding to a relative variability of 0.83% to 2.83%. The mean of the relative variability was within 1.68% for the "A" specimens and 2.15% for the "B" specimens. However, the difference was not significant, probably due to the limited number of "B" specimens. The systematic error of the Moiré measurements in relation to the reference methods was surprisingly low, ranging from -0.12 mm3 to 7.67 mm3. The relative systematic error, expressed as a percentage of reference volume, ranged between 0.06% and -2.23%. The mean of the relative error for the more complex "B" specimens was 1.37%, which was less accurate in comparison to the more simply formed "A" specimens with a relative systematic error of 0.35%. Therefore, in this in vitro model it was possible to measure volume differences of geometrically different formed specimens, mimicking localized alveolar ridge defects, with a validity within 2.2% and with a variability of less than 2.8%.