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Introducción. La epidemiología del ántrax en Perú es poco conocida. Su alto potencial epidémico y epizoótico podría amenazar la salud pública, especialmente desde sus regiones endémicas. Objetivo. Caracterizar los casos de ántrax humano en Perú del 2015 al 2019. Métodos. Se realizó un estudio transversal retrospectivo, a partir de los datos del Sistema Nacional de Vigilancia Epidemiológica e investigaciones de brotes en Perú del 2015 al 2019. Resultados. 71 casos de ántrax humano fueron registrados, 34 % (n = 24) confirmados y66 % (n = 47) probables. Los más afectados fueron varones (55 %) y el grupo etario de 30 a 59 años (45 %). Los casos estuvieron distribuidos principalmente en la costa norte del país. La forma cutánea autolimitada en miembros superiores fue la presentación clínica más frecuente. El 94 % (n = 67) de los casos tuvieron contacto con ganado vacuno infectado. Conclusión. Los casos de ántrax humano en Perú fueron en su mayoría de la forma cutánea, que se presentaron por brotes focalizados en áreas con antecedentes de trasmisión zoonótica. Este reporte pretende aportar al conocimiento epidemiológico de esta enfermedad y servir como insumo en la implementación de medidas de prevención y control.
Introduction. The epidemiology of anthrax in Peru is poorly understood. Its high epidemic and epizootic potential could threaten public health, especially in its endemic regions. Objective. To characterize cases of human anthrax in Peru from 2015 to 2019. Methods. A retrospective cross-sectional study was carried out; based on data from the National Epidemiological Surveillance System and investigations of anthrax outbreaks from 2015 to 2019 in Peru. Results. 71 cases of human anthrax were registered, 34 % (n = 24)confirmed and 66 % (n = 47) probable. The most affected were males (55 %) and the age group from 30to 59 years (45 %), distributed mainly on the north coast of the country. The self-limited cutaneous form was the most frequent clinical presentation. 94% (n = 67) of the cases had contact with infected cattle. Conclusions. The cases of human anthrax in Peru appear as focalized outbreaks in areas with a history of zoonotic transmission. This report aims to contribute to the epidemiological knowledge of this disease and serve as input in the implementation of prevention and control measures.
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Preventive programs are standardized behavioral interventions that either stop or reduce course of diseases. Indeed, it is known that much of public health programs are synonymous to preventive medicine, which constitute major theme in primary healthcare. The objective of this study was to provide preliminary summaries of research programs, which determined nutritional status on visual impairment (VI) among children,utilization of ITNs and reduction of HIV/AIDS infection in Nigeria. The studies adopted intervention approaches. In Delta state, antioxidant vitamins and ferrous sulphate were administered to participants, to assess impact on visual impairment. In health education on utilizationof ITNs in Bayelsa and Rivers states; as well as on HIV/AIDS infection in Northern Nigeria. Statistically, the studies followed a quantitative method. Baseline percentages of vitamin A and C deficiencies, anaemia, and VI differed with respective post-intervention levels. Post-intervention result showed that 92.1% owned ITNs, improved knowledge of causes and consequences of malaria. On HIV, community-based television, and radio awareness programs on the use of condom influenced the reduction of HIV/AIDS infection by up to 30%. In conclusion, the preliminary reports indicatethatantioxidant vitamins and iron supplementation ameliorated anaemia and VI. Public health awarenesscampaign influenced behavioural change wheel on use of ITNs as well asuse of condom for the reduction of HIV/AIDS infection in Nigeria.
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ABSTRACT Leptogenys elzasoares new species, is described from workers and a male collected near Manaus in the Brazilian Amazon. The worker is recognizable by the presence of 12 chaetae (stout setae) on the clypeal median lobe, the straight mandible, and its bicolored body; the head and mesosoma are black while the gaster is brightly ferruginous. For the first time, the males of L. bohlsi Emery, 1896, L. unistimulosa Roger, 1863, and L. parensis Lattke, 2011 are described. A new key to the males of the unistimulosa species group is provided, and the key to workers of Lattke (2011) is updated to include the new species. Finally, we also report new records of L. parensis from French Guiana, expanding the known distribution by over 780 km northwest.
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Objective: This paper describes sexual behaviours and their associated factors among young people. Design: The study design is cross-sectional. Setting: Dodowa Health and Demographic Surveillance Site (DHDSS) in Ghana's Shai-Osudoku and Ningo Prampram districts. Participants: Young people aged 10 to 24 years, median age 17 years. Outcome measures: Self-reported to have ever had sex, non-use of a condom at last sex, and ever been pregnant or gotten someone pregnant. Results: Of the 1689 young people; 42% reported having ever had sex, not using a condom at last sexual activity (64%), and ever been pregnant or gotten someone pregnant (41%). The proportion of non-use of condoms at last sex was high across all age groups but was highest (93%) in a small proportion of 10 to 14-year-olds who have ever had sex. Higher proportions of females than males; were reported to have ever had sex (46%), not using a condom at their last sex (66%) and ever been pregnant or getting someone pregnant (56%). Age group (20 to 24), females, primary or junior high school, living alone and lower household socio-economic status were risk factors associated with all three outcome measures. Conclusion: Risky sexual behaviour is high among young people in the Dodowa HDSS. Therefore, interventions that promote safer sexual practices and help young people make timely decisions on their sexual and reproductive health care needs are required.
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Humans , Male , Female , Family Characteristics , Risk Factors , Outcome Assessment, Health Care , Economic Status , Sexual BehaviorABSTRACT
Purpose@#Central retinal artery occlusion (CRAO) is a vision-threatening condition with a potentially poor visual prognosis. Many different treatment modalities are suggested but controversy remains regarding effectiveness of these treatments. The purpose of this study is to perform a systematic review and meta-analysis in addition to analyzing retrospective data at our own tertiary care center regarding effectiveness of hyperbaric oxygen therapy (HBOT) in treatment of CRAO. @*Methods@#The PubMed, Scopus, and the Cochrane Library are searched from the date of database inception to September 2021 to conduct a review based on the PRISMA (preferred reporting items for systematic review and meta-analysis), evaluating the role of HBOT in visual recovery of CRAO patients. In addition, a retrospective chart review of patients clinically diagnosed with CRAO at our university-based hospital (University of Texas Health, San Antonio, TX, USA) from year 2011 to 2021 was conducted. @*Results@#After a review of 376 articles, three articles met the inclusion criteria for meta-analysis, where a total of 207 patients received HBOT versus 89 patients that did not receive any form of oxygen therapy. Analysis of these results demonstrate that HBOT in CRAO patients does not enhance the final visual outcome (p = 0.83). Similar conclusion was also drawn from retrospective analysis of 48 patients (15 HBOT versus 33 controls) at our tertiary care center, where no visual benefit was observed in the HBOT group. @*Conclusions@#HBOT does not appear to improve final visual outcome and concerns remain regarding adverse reactions such as barotrauma and generalized seizures. Large, randomized studies are required for further understanding of the role of HBOT in treatment of CRAO.
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Background/Aims@#Jackhammer esophagus is an uncommon heterogeneous motility disorder associated with a distal contractile integral > 8000 mmHg · sec · cm. The spectrum of abnormality ranges from a relatively normal looking contraction to chaotic repetitive contractions akin to a jackhammer. Although previous studies have shown an uncertain correlation between peristaltic vigor and symptoms, we hypothesize that symptoms may be more severe with repetitive contractions as opposed to an elevated contractile measure. Thus, this study aims to investigate whether symptom severity is related to the contraction pattern in the patients with hypercontractile esophagus. @*Methods@#Patients with hypercontractile esophagus were retrospectively identified, their demographic and high-resolution manometry characteristics were collected. Contraction pattern on high-resolution manometry was categorized into single-peak and multiple-peak.Comparison was performed between patients with single-peak and multiple-peak. @*Results@#Altogether 35 patients (age range, 45-70 years; female:male, 24:11) were included. Seven patients presented with single-peak hypercontractile swallows, while 28 patients presented with multiple-peak hypercontractile swallows. The patients with multiple-peak showed higher Brief Esophageal Dysphagia Questionnaire scores compared with patients with single-peak. The jackhammer swallows with multiple-peak were associated with higher distal contractile integral values, longer distal latency intervals, and a lower integrated relaxation pressure. @*Conclusions@#Repetitive contractions akin to a jackhammer were common amongst patients with hypercontractile esophagus. Patients with the jackhammer pattern also presented with more severe symptoms. Further distinction of hypercontractile esophagus into a jackhammer dominant subtype may be warranted.
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Background/Aims@#Incorporation of complementary and provocative test swallows to the high-resolution manometry (HRM) protocol offers potential to address limitations posed by HRM protocols that involve only a single swallow type. The aim of this study is to describe normal findings of a comprehensive HRM testing protocol performed on healthy asymptomatic volunteers. @*Methods@#Thirty healthy asymptomatic volunteers completed HRM with 5-mL liquid swallows in the supine position. They also completed 5-mL liquid swallows in the upright position, viscous swallows, solid test swallows, multiple rapid swallows, and a rapid drink challenge.HRM studies were analyzed via Chicago classification version 3.0. @*Results@#The median (5th-95th percentiles) for integrated relaxation pressure (IRP) on supine swallows was 11 (4-16) mmHg; IRP was lower than supine on upright liquid 9 (0-17) mmHg, viscous 6 (0-15) mmHg, solid 9 (1-19) mmHg, multiple rapid swallows 3 (0-12) mmHg, and rapid drink challenge 5 (–3-12) mmHg; P < 0.005. While an “elevated” IRP value was observed on 1 to 2 test maneuvers in 8/30 (27%) subjects, all 30 subjects had an IRP value < 12 mmHg on at least one of the test maneuvers. @*Conclusions@#Normal values and findings from a comprehensive HRM testing protocol are reported based on evaluation of 30 healthy asymptomatic volunteers. Isolated “abnormalities” of IRP and contractile parameters were observed in the majority (80%) of these asymptomatic subjects, while all subjects also had normal features observed. Thus, the definition of “normal” should be recalibrated to focus on the entirety of the study and not individual metrics.
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Background/Aims@#Jackhammer esophagus is an uncommon heterogeneous motility disorder associated with a distal contractile integral > 8000 mmHg · sec · cm. The spectrum of abnormality ranges from a relatively normal looking contraction to chaotic repetitive contractions akin to a jackhammer. Although previous studies have shown an uncertain correlation between peristaltic vigor and symptoms, we hypothesize that symptoms may be more severe with repetitive contractions as opposed to an elevated contractile measure. Thus, this study aims to investigate whether symptom severity is related to the contraction pattern in the patients with hypercontractile esophagus. @*Methods@#Patients with hypercontractile esophagus were retrospectively identified, their demographic and high-resolution manometry characteristics were collected. Contraction pattern on high-resolution manometry was categorized into single-peak and multiple-peak.Comparison was performed between patients with single-peak and multiple-peak. @*Results@#Altogether 35 patients (age range, 45-70 years; female:male, 24:11) were included. Seven patients presented with single-peak hypercontractile swallows, while 28 patients presented with multiple-peak hypercontractile swallows. The patients with multiple-peak showed higher Brief Esophageal Dysphagia Questionnaire scores compared with patients with single-peak. The jackhammer swallows with multiple-peak were associated with higher distal contractile integral values, longer distal latency intervals, and a lower integrated relaxation pressure. @*Conclusions@#Repetitive contractions akin to a jackhammer were common amongst patients with hypercontractile esophagus. Patients with the jackhammer pattern also presented with more severe symptoms. Further distinction of hypercontractile esophagus into a jackhammer dominant subtype may be warranted.
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Background/Aims@#Incorporation of complementary and provocative test swallows to the high-resolution manometry (HRM) protocol offers potential to address limitations posed by HRM protocols that involve only a single swallow type. The aim of this study is to describe normal findings of a comprehensive HRM testing protocol performed on healthy asymptomatic volunteers. @*Methods@#Thirty healthy asymptomatic volunteers completed HRM with 5-mL liquid swallows in the supine position. They also completed 5-mL liquid swallows in the upright position, viscous swallows, solid test swallows, multiple rapid swallows, and a rapid drink challenge.HRM studies were analyzed via Chicago classification version 3.0. @*Results@#The median (5th-95th percentiles) for integrated relaxation pressure (IRP) on supine swallows was 11 (4-16) mmHg; IRP was lower than supine on upright liquid 9 (0-17) mmHg, viscous 6 (0-15) mmHg, solid 9 (1-19) mmHg, multiple rapid swallows 3 (0-12) mmHg, and rapid drink challenge 5 (–3-12) mmHg; P < 0.005. While an “elevated” IRP value was observed on 1 to 2 test maneuvers in 8/30 (27%) subjects, all 30 subjects had an IRP value < 12 mmHg on at least one of the test maneuvers. @*Conclusions@#Normal values and findings from a comprehensive HRM testing protocol are reported based on evaluation of 30 healthy asymptomatic volunteers. Isolated “abnormalities” of IRP and contractile parameters were observed in the majority (80%) of these asymptomatic subjects, while all subjects also had normal features observed. Thus, the definition of “normal” should be recalibrated to focus on the entirety of the study and not individual metrics.
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Background/Aims@#High-resolution manometry (HRM) performed without sedation is the standard procedure. However, some patients cannot tolerate transnasal placement of the manometry catheter. We aim to assess the practice of performing manometry after endoscopy with conscious sedation by evaluating its impact on esophageal motility findings. @*Methods@#Twelve asymptomatic adult volunteers and 7 adult patients completed high-resolution impedance manometry (HRIM) approximately 1 hour after conscious sedation with midazolam and fentanyl (post-sedation) and again on a different day with no-sedation. The nosedation HRIM involved 2 series of swallows separated in time by 20 minutes (no-sedation-1 and no-sedation-2) for the volunteers; patients completed only 1 series of swallows for no-sedation HRM. @*Results@#A motility diagnosis of normal motility was observed in all 12 volunteers post-sedation. Two volunteers had a diagnosis of borderline ineffective esophageal motility, one during the no-sedation-1 period and the other during the no-sedation-2 period; all of the other no-sedation HRIM studies yielded a normal motility diagnosis. Six of seven patients had the same diagnosis in both no-sedation and post-sedation HRM, including 1 distal esophageal spasm, 3 achalasia (2 type II and 1 type III), and 2 esophagogastric junction outflow obstruction. Only one patient’s HRM classification changed from ineffective esophageal motility at no-sedation to normal esophageal motility at post-sedation. @*Conclusions@#Performing HRIM after endoscopy with conscious sedation had minimal clinical impact on the motility diagnosis or motility parameters. Thus, this approach may be a viable alternative for patients who cannot tolerate unsedated catheter placement.
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ABSTRACT We report new records of Gnamptogenys caelata Kempf (1967) and Gnamptogenys minuta (Emery, 1896) from Brazil. We also describe Gnamptogenys piei n. sp. from Southeast Brazil. This distinctive new species is known only from a single worker found in leaf litter from montane forests of the Mantiqueira mountains in Itatiaia National Park, Rio de Janeiro State, Brazil. The specimen was collected at 1991 m above sea level, an infrequent altitude for minuta-group ants, usually more common at lower altitudes. The new species is imaged, compared with other minuta-group species, and an updated identification key for all known species of the minuta-group is included.
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Myxoid liposarcoma accounts for 30% to 50% of all liposarcomas, which is the second most common soft tissue tumor. It is usually painless slowly growing mass in the deep-seated soft tissue of the lower extremities or the peritoneum, with a strong metastatic predilection to the spine. Metastatic myxoid liposarcoma typically shows low signal intensity on T1 sequences with hyper-intensities on T2 sequences. In contrast to vertebral hemangioma, it shows increased signal intensity in both T1 and T2 sequences. We demonstrate 2 cases of metastatic myxoid liposarcoma with atypical MRI pattern. According to the histopathology and the clinical signs, we believe that increasing round cell cellularity and fat content is correlated to the increased T1 signal intensity and clinical aggressiveness. In conclusion, the atypical MRI pattern for vertebral metastatic lesions in patients with myxoid liposarcoma should be taken into consideration to prevent the delay in diagnosis and standard of care.
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RESUMEN Listeria monocytogenes (Lm) es un patógeno emergente causante de enfermedades transmitidas por alimentos de consumo masivo principalmente cárnicos y lácteos. Actualmente se buscan diferentes estrategias para su control, entre ellas compuestos naturales producidos por otros microorganismos como ácidos orgánicos y otros compuestos como lactoferrina, lisozima y bacteriocinas, estas últimas producidas por especies de bacterias como Lactobacillus plantarum (Lp). El objetivo de esta investigación fue determinar el efecto de cepas de Lp aisladas de suero costeño sobre el control de crecimiento de L. monocytogenes inoculada en co-cultivos. Se realizaron curvas de crecimiento para Lm, Lp 60-1 y Lp 62-1 y co-cultivos de cada Lp con Lm. La cinética de crecimiento fue evaluada determinando la viabilidad durante 24h en agares selectivos. La tasa de crecimiento de L. monocytogenes inoculada como control en leche UHT y en co-cultivos, presentaron diferencias significativas (p<0,05) entre los tratamientos, evidenciando que el control alcanzó un valor promedio de tasa de crecimiento mayor (µmax =0,65 h-1), que el obtenido para los co-cultivos con Lp 60-1 y Lp 62-1 (µmax =0,22 h-1 y µmax =0,27 h-1 respectivamente). La mayor diferencia fue alcanzada en el co cultivo con Lp 60-1, obteniendo el menor valor promedio de tasa de crecimiento de Lm. Los resultados demuestran la eficiencia de las cepas de Lp (60-1 y 62-1) para el control de crecimiento de Lm en leche UHT comercial, siendo esta una alternativa para reducir el uso de aditivos químicos durante la producción de lácteos.
ABSTRACT Listeria monocytogenes (Lm) is an emerging pathogen causing foodborne diseases especially in dairy products and meat. Nowadays are sought different strategies to their control for example natural compounds produced by microorganisms, such as organic acids and other compounds as lactoferrin, lysozyme and bacteriocins, the latter produced by bacterial species as Lactobacillus plantarum (Lp). The main objective of this research was to determine the effect of Lp strains isolated from "Suero costeño" inoculated in co-culture over the L. monocytogenes growth. There where made growth kinetics for Lm, Lp 60-1 and Lp 62-1 and co-cultures of each Lp with Lm. The growth kinetic was evaluated establishing the viability during 24h in selective culture media. The growth rate of L. monocytogenes inoculated in UHT milk and in co-culture, showed a significative difference (p<0,05) between the treatments, demonstrating that the control reach an average value of growth rate higher (µmax =0,65 h-1) than the one obtained for the co-culture with Lp 60-1 and Lp 62-1 (µmax =0,22 h-1 and µmax =0,27 h-1 respectively). The higher difference between the last two treatments was given by the treatment with Lp 60-1, obtaining the lowest average value for the Lm growth. The results showed the efficiency of the Lp strains (60-1 y 62-1) for the growth control of Lm in UHT commercial milk, being an alternative to reduce the use of chemical additives during the production of dairy products.
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No abstract available.
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Abstract:Remote sensing and traditional ecological knowledge (TEK) can be combined to advance conservation of remote tropical regions, e.g. Amazonia, where intensive in situ surveys are often not possible. Integrating TEK into monitoring and management of these areas allows for community participation, as well as for offering novel insights into sustainable resource use. In this study, we developed a 250 m resolution land-cover map of the Western Guyana Shield (Venezuela) based on remote sensing, and used TEK to validate its relevance for indigenous livelihoods and land uses. We first employed a hyper-temporal remotely sensed vegetation index to derive a land classification system. During a 1 300 km, eight day fluvial expedition in roadless areas in the Amazonas State (Venezuela), we visited six indigenous communities who provided geo-referenced data on hunting, fishing and farming activities. We overlaid these TEK data onto the land classification map, to link land classes with indigenous use. We characterized land classes using patterns of greenness temporal change and topo-hydrological information, and proposed 12 land-cover types, grouped into five main landscapes: 1) water bodies; 2) open lands/forest edges; 3) evergreen forests; 4) submontane semideciduous forests, and 5) cloud forests. Each land cover class was identified with a pulsating profile describing temporal changes in greenness, hence we labelled our map as "The Forest Pulse". These greenness profiles showed a slightly increasing trend, for the period 2000 to 2009, in the land classes representing grassland and scrubland, and a slightly decreasing trend in the classes representing forests. This finding is consistent with a gain in carbon in grassland as a consequence of climate warming, and also with some loss of vegetation in the forests. Thus, our classification shows potential to assess future effects of climate change on landscape. Several classes were significantly connected with agriculture, fishing, overall hunting, and more specifically the hunting of primates, Mazama americana, Dasyprocta fuliginosa, and Tayassu pecari. Our results showed that TEK-based approaches can serve as a basis for validating the livelihood relevance of landscapes in high-value conservation areas, which can form the basis for furthering the management of natural resources in these regions. Rev. Biol. Trop. 64 (4): 1661-1682. Epub 2016 December 01.
Resumen:La teledetección y el conocimiento ecológico tradicional (CET) se pueden combinar para avanzar en la conservación de regiones tropicales remotas como la Amazonía, donde la toma de datos intensiva in situ a menudo es imposible. Integrar el CET en el seguimiento y el manejo de estas áreas permite la participación de la comunidad, y ofrece nuevos puntos de vista sobre el uso sostenible de los recursos naturales. En este estudio se desarrolla un mapa de cobertura del suelo del Escudo Guayanés (Venezuela), con una resolución espacial de 250 m, basado en datos de teledetección, y se utiliza el CET para validar su relevancia en relación con la subsistencia de los pueblos indígenas y el uso que éstos hacen del territorio. En primer lugar se ha empleado un índice de vegetación basado en teledetección hiper-temporal para realizar una clasificación del territorio. Durante una expedición fluvial de 8 días, a lo largo de 1 300 km por áreas sin carreteras en el Estado Amazonas (Venezuela), se han visitado seis comunidades que han proporcionado datos geo-referenciados sobre sus actividades cinegéticas, pesqueras y agrícolas. Estos datos de CET se han superpuesto al mapa de clasificación, con el fin de relacionar las clases de coberturas con los usos indígenas. Se han caracterizado las clases de cobertura en función de patrones de cambio temporal del verdor y la topo-hidrografía, y se han propuesto 12 tipos de cobertura del suelo, agrupadas en cinco tipos principales de paisaje: 1) masas de agua; 2) campo abierto/ márgenes del bosque; 3) bosques siempre-verdes; 4) bosques semi-caducifolios submontanos; y 5) bosques nublados. Cada clase de cobertura del suelo se ha identificado con un perfil pulsátil que describe cambios temporales en el verdor, de ahí que el mapa haya sido titulado "El Pulso del Bosque". Estos perfiles de verdor han mostrado una tendencia ligeramente ascendente, durante el periodo 2000 a 2009, en las clases que representan pastizales y zonas de matorral, así como una tendencia ligeramente decreciente en las clases que representan bosques. Este hallazgo es compatible con la ganancia de carbono en los pastizales como consecuencia del calentamiento del clima, y también con una cierta pérdida de vegetación en los bosques. De este modo, nuestra clasificación muestra potencial para la evaluación de efectos futuros del cambio climático sobre el paisaje. Algunas clases han resultado estar significativamente relacionadas con la agricultura, la pesca, la caza como práctica general, y más concretamente con la caza de primates, de Mazama Americana, Dasyprocta fuliginosa, y Tayassu pecari. Los resultados demuestran la utilidad de las aproximaciones basadas en CET como base para validar la importancia del paisaje, en áreas con alto valor de conservación, para la supervivencia de las personas, lo que proporciona una base para avanzar en el manejo de los recursos naturales en estas regiones.
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Humans , Indians, South American/ethnology , Forests , Remote Sensing Technology/methods , Geographic Mapping , Spatio-Temporal Analysis , Ecological Parameter Monitoring/methods , Reference Values , Venezuela/ethnology , Logistic Models , Reproducibility of Results , Conservation of Natural Resources , Grassland , Rivers , Agriculture/statistics & numerical dataABSTRACT
O termo osseointegração refere-se à ancoragem de um implante no tecido ósseo, de forma que esse implante possa suportar carga funcional. O processo de osseointegração envolve vários mecanismos biológicos e o entendimento desses mecanismos e do papel da superfície dos implantes nesse processo, auxiliará o clínico de duas maneiras importantes: 1) na escolha dos implantes mais apropriados para os seus pacientes; e 2) no reconhecimento de problemas que possam surgir após a colocação de um implante. Nesse artigo, abordaremos uma nova perspectiva sobre a osseointegração, baseada em um trabalho recente que demonstrou que a reparação peri--implantar pode ser considerada um processo de restauração da homeostasia óssea. Esse processo representa um fenômeno universal, com vários exemplos nas ciências naturais e biológicas. O crescimento exponencial da ancoragem do implante no tecido ósseo através do tempo leva a um novo equilíbrio que pode ser representado por uma simples equação, onde dois parâmetros são importantes: 1) o valor máximo da ancoragem entre o implante e osso (novo equilíbrio tecidual)e 2) o período através do qual esse equilíbrio é adquirido. Portanto, em condições experimentais,é importante monitorar o processo de reparo por um longo período de tempo para que esse novo equilibrio seja obtido. Esse período de tempo necessário para que a hemostasia seja adquirida é descrito por um parâmetro matemático chamado Tau, que surge como uma maneira única de quantificar e comparar a performance do processo de osseointegração dos implantes. Essa nova perspectiva sobre a osseointegração será discutida em detalhes nesse artigo.
Osseointegration refers to the anchorage of an implant in bone, to a degree that can with stand functional loading. Osseointegration comprises several distinct biological mechanisms. An under standing these phenomena, and the role of implant surface topography in this process,will assist the clinician in two important ways: 1) It will inform their choice of the most appropriate implant designs for their patients, and 2) It will facilitate their recognition of problemsthat may arise after implant placement. We describe herein a new perspective on osseointegration.It is based on recent work that has demonstrated that peri-implant healing may beregarded as a restoration of bony homeostasis. Restoration of homeostasis is a universal phenomenon of which there are a multitude of examples in the natural and biological worlds. Applied to bone healing, the exponential rise in bone anchorage with time reaches the new equilibrium.This can be modeled using a simple equation where two important parameters emerge: 1) The ultimate value of implant/bone anchorage, which represents the new tissue equilibrium and 2)The rate at which this equilibrium is reached. Thus, experimentally, it is important to monitorhealing over a relatively long time so that the new bony equilibrium, can be achieved. However,the rate at which homeostasis is reached, described by a single mathematical parameter tau,emerges as a unique means by which the osseointegration performance of implants can bequantified and compared. This new perspective on osseointegration will be discussed in moredetails herein.
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Homeostasis/physiology , /methods , Dental Implants , Osseointegration/physiologyABSTRACT
Aims: To investigate the effect of fansidar® and vitamin C co-administration on serum electrolyte and body weight indices of Wistar albino rats. Place and Duration of Study: Department of Medical Biochemistry, Cross River University of Technology, Okuku Campus, between August 2013 and June 2014. Methodology: Sixty (60) Wistar albino rats were divided into three groups I, II, III (n=20; 10 male, 10 female) weighing between 180-200 g. Group I was designated as the control and received distilled water, groups II and III were treated with 14.29 mg/kg body weight of fansidar® and 14.29 mg/kg body weight each of fansidar® + vitamin C respectively for 14 days. The animals were then sacrificed and blood collected for serum electrolyte analysis. Results: The results obtained showed that the serum [Na+] was significantly (P<0.05) increased in group II females only compared with control. There was a significant (P<0.05) increase in the serum [K+] of groups II and III males and group III females compared with control. There was also a significant (P<0.05) elevation of [CO2] in group II rats (irrespective of sex) compared with the control. The [Cl-] of only the males in groups II and III was significantly (P<0.05) reduced compared with the control. The results of body weight indices investigated showed a significant (P<0.05) decrease in mean weight increase (MWI) and growth rate (GR) of all the test groups compared with the control, however, group III compared with group II was significantly (P<0.05) increased. Conclusion: The alterations in serum electrolyte on fansidar® administration were pronounced in males than females except in the sodium electrolyte levels. The co-administration of vitamin C may reverse the adverse alterations in serum electrolyte and body weight changes caused by fansidar® administration.