Relationship between maternal periodontal disease and birth of preterm low weight babies Associação entre doença periodontal materna e nascimento de bebês prematuros e de baixo peso

It has been recently suggested that periodontal disease is an associated factor for prematurity and low birth weight. The aim of this work was to assess the periodontal status of puerperae and determine its possible relationship with preterm low birth weight (PLBW) delivery. The sample included 59 women seen at two maternity hospitals in Juiz de Fora, MG, Brazil. Nineteen mothers had premature and low birth weight babies (gestational age below 37 weeks and birth weight below 2,500 g - group I), and 40 had mature, normal weight babies (gestational age over 37 weeks and birth weight over 2,500 g - group II). The mothers' data were obtained from medical files, interview, and periodontal clinical examination carried out up to 48 hours after delivery. The Periodontal Screening and Recording (PSR) was used for periodontal assessment. The association between periodontal disease and PLBW was expressed as odds ratio (OR). There was a higher rate of periodontal disease in group I (84.21% - 16/19) as compared with group II (37.5% - 15/40). The data also showed a significant association between periodontal disease and PLBW (OR = 8.9 - 95% CI: 2.22-35.65 - p = 0.001). It was concluded that maternal periodontal disease was an associated factor for prematurity and low birth weight in this sample.<br>Estudos recentes sugerem que a doença periodontal é um fator associado para prematuridade e baixo peso ao nascimento. O objetivo deste trabalho foi avaliar a condição periodontal de puérperas e determinar sua possível associação com nascimentos prematuros e de baixo peso (NPBP). A amostra incluiu 59 mães atendidas em duas maternidades de Juiz de Fora, MG. Dentre essas, 19 tiveram bebês prematuros e de baixo peso (idade gestacional menor que 37 semanas e peso ao nascimento menor que 2.500 g - grupo I) e 40 tiveram bebês a termo e de peso normal (idade gestacional maior que 37 semanas e peso ao nascimento maior que 2.500 g - grupo II). Os dados das mães foram obtidos através de prontuário médico, entrevista e exame clínico periodontal, realizado até 48 horas após o parto. O Registro Periodontal Simplificado (RPS) foi utilizado para avaliar a condição periodontal. A associação entre doença periodontal e NPBP foi expressa em "odds ratio" (OR). Os resultados demonstraram uma freqüência maior de doença periodontal no grupo I (84,21% - 16/19) em comparação ao grupo II (37,5% - 15/40). Os dados demonstraram ainda uma associação significante entre a presença de doença periodontal e NPBP (OR = 8,9 - IC de 95%: 2,22-35,65 - p = 0,001). Concluiu-se que a doença periodontal materna atuou como fator associado para a prematuridade e o baixo peso ao nascimento nesta amostra

Time-resolved emission imaging microscopy using phosphorescent metal complexes: taking FLIM and PLIM to new lengths

Luminescent metal complexes are increasingly being investigated as emissive probes and sensors for cell imaging using what is traditionally termed fluorescence microscopy. The nature of the emission in the case of second- and third-row metal complexes is phosphorescence rather than fluorescence, as it emanates from triplet rather than singlet excited states, but the usual terminology overlooks the distinction between the quantum mechanical origins of the processes. In steady-state imaging, such metal complexes may be alternatives to widely used fluorescent organic molecules, used in exactly the same way but offering advantages such as ease of synthesis and colour tuning. However, there is a striking difference compared to fluorescent organic molecules, namely the much longer lifetime of phosphorescence compared to fluorescence. Phosphorescence lifetimes of metal complexes are typically around a microsecond compared to the nanosecond values found for fluorescence of organic molecules. In this contribution, we will discuss how these long lifetimes can be put to practical use. Applications such as time-gated imaging allow discrimination from background fluorescence in cells and tissues, while increased sensitivity to quenchers provides a means of designing more responsive probes, for example, for oxygen. We also describe how the technique of fluorescence lifetime imaging microscopy (FLIM) – which provides images based on lifetimes at different points in the image – can be extended from the usual nanosecond range to microseconds. Key developments in instrumentation as well as the properties of complexes suitable for the purpose are discussed, including the use of two-photon excitation methods. A number of different research groups have made pioneering contributions to the instrumental set-ups, but the terminology and acronyms have not developed in a systematic way. We review the distinction between time-gating (to eliminate background emission) and true time-resolved imaging (whereby decay kinetics at each point in an image are monitored). For instance, terms such as PLIM (phosphorescence lifetime imaging microscopy) and TRLM (time-resolved luminescence microscopy) refer essentially to the same technique, whilst TREM (time-resolved emission imaging microscopy) embraces these long timescale methods as well as the more well-established technique of FLIM