Micronucleus test in mussels Perna perna fed with the toxic dinoflagellate Prorocentrum lima

Micronucleus (MN) and other nuclear abnormalities have been measured in the hemocytes of mussels Perna perna to verify whether feeding mussels with different concentrations of Prorocentrum lima results in accumulation of levels of okadaic acid (OA) capable of inducing genotoxic effects at the chromosome level, as evidenced by micronuclei and nuclear abnormalities. Four groups of 12 mussels housed individually in aquaria containing filtered seawater were fed with different concentrations of P. lima. Another group collected directly from the production area served as outdoor control. A significantly higher frequency of MN and nuclear lesions was observed in hemocytes from the groups fed P. lima.     

Mapping of three novel loci for non‐syndromic autosomal recessive mental retardation (NS‐ARMR) in consanguineous families from Pakistan

Rafiq MA, Ansar M, Marshall CR, Noor A, Shaheen N, Mowjoodi A, Khan MA, Ali G, Amin‐ud‐Din M, Feuk L, Vincent JB, Scherer SW. Mapping of three novel loci for non‐syndromic autosomal recessive mental retardation (NS‐ARMR) in consanguineous families from Pakistan. To date, of 13 loci with linkage to non‐syndromic autosomal recessive mental retardation (NS‐ARMR), only six genes have been established with associated mutations. Here we present our study on NS‐ARMR among the Pakistani population, where people are traditionally bound to marry within the family or the wider clan. In an exceptional, far‐reaching genetic survey we have collected more than 50 consanguineous families exhibiting clinical symptoms/phenotypes of NS‐ARMR. In the first step, nine families (MR2‐9 and MR11) with multiple affected individuals were selected for molecular genetic studies. Two families (MR3, MR4) showed linkage to already know NS‐ARMR loci. Fifteen affected and 10 unaffected individuals from six (MR2, MR6, MR7, MR8, MR9 and MR11) families were genotyped by using Affymetrix 5.0 or 6.0 single‐nucleotide polymorphism (SNP) microarrays. SNP microarray data was visually inspected by dChip and genome‐wide homozygosity analysis was performed by HomozygosityMapper. Additional mapping was performed (to exclude false‐positive regions of homozygosity called by HomozygosityMapper and dChip) on all available affected and unaffected members in seven NS‐ARMR families, using microsatellite markers. In this manner we were able to map three novel loci in seven different families originating from different areas of Pakistan. Two families (MR2, MR5) showed linkage on chromosome 2p25.3‐p25.2. Three families (MR7, MR8, and MR9) that have been collected from the same village and belong to the same clan were mapped on chromosome 9q34.3. MR11 maps to a locus on 9p23‐p13.3. Analysis of MR6 showed two positive loci, on chromosome 1q23.2‐q23.3 and 8q24.21‐q24.23. Genotyping in additional family members has so far narrowed, but not excluded the 1q locus. In summary, through this study we have identified three new loci for NS‐ARMR, namely MRT14, 15 and 16.     

In vivo temporal and spatial distribution of depolarization and repolarization and the illusive murine T wave

This study assessed in vivo temporal and spatial electrophysiological properties of murine hearts and the effect of manipulation of transmural action potential durations (APDs) on T wave morphology. Monophasic action potentials (MAPs) were acquired from multiple left ventricular sites. All MAPs exhibited a plateau phase, with a spike and dome appearance being present in epicardial recordings. Activation occurred from endocardial apex to epicardial apex and apex to base while repolarization occurred from base (shortest 90 η₀ level of repolarization (MAP₉₀), 95.4 ± 8.9 ms) to apex and epicardium to endocardium (longest MAP₉₀, 110.77 ± 10.6 ms). The peak of phase 0 of the epicardial base MAP correlated with the return to baseline of the initial and usually dominant waveform of the QRS and the onset of the second usually smaller wave, which clearly occurred in early repolarization, thus establishing where depolarization ended and repolarization began on the murine ECG. This second waveform was similar to the J wave seen in larger animals. Despite temporal and spatial electrophysiological similarities, a T wave is frequently not seen on a murine ECG. There are several determinants of T wave morphology, including transmural activation time, slope of phase 3 repolarization and differences in epicardial, endocardial and M cell APDs. Experimental manipulation of murine transmural gradients by shortening epicardial MAP₉₀ to 84% of endocardial MAP₉₀ the epicardial/endocardial ratio in larger mammals when a positive T wave is present, resulted in a positive murine T wave. Thus, manipulation of the transmural gradients such that they are similar to larger mammals can result in T waves with similar morphology.     

急性和慢性呼吸道炎症疾病激肽形成机制探讨

目的探讨急性和慢性呼吸道炎症过程中激肽的生成途径和机制。方法测定支气管肺癌伴阻塞性肺炎,慢性支气管炎和健康对照组支气管肺泡灌洗液（ＢＡＬＦ）凝胶过滤前后激肽、激肽形成酶活性（ＴＡＭＥｅａ）,血浆血管舒缓素（ＰＫ）和α２巨球蛋白（α２Ｍ）,并进一步鉴定ＴＡＭＥｅａ性质。结果急、慢性组ＴＡＭＥｅａ和激肽水平与健康对照组比较差异有显著性（Ｐ＜０００１,Ｐ＜０．０１）,但两组间差异无显著性（Ｐ＞００５）;急性组ＰＫ和α２Ｍ与慢性组比较差异有显著性（Ｐ＜０００１）。凝胶过滤结果显示：急性组ＢＡＬＦ的ＴＡＭＥｅａ最高峰位于分子量约８０００００处,与第一个α２Ｍ峰重叠,而慢性组的最高峰位于４００００处。ＴＡＭＥｅａ抑制试验证实８０００００处的ＴＡＭＥｅａ来自于ＰＫ;而４００００处的ＴＡＭＥｅａ主要来源于组织血管舒缓素（ＴＫ）。结论急性呼吸道炎症的ＴＡＭＥｅａ主要来自血浆的ＰＫ;而慢性呼吸道炎症则以局部组织腺体分泌的ＴＫ为主。     

Allocation of health care resources in the neonatal and perinatal area �CCPS Symposium 1996

There have been publically expressed concerns about the costs and allocation of neonatal and perinatal health care resources in Canada and elsewhere for the past 15 years. This paper reports information from a symposium held during the 1996 Canadian Paediatric Society (CPS) annual meeting sponsored by the CPS Section on Perinatal Medicine. Experts in perinatal epidemiology, health care economics, public policy and finance, and consumer perspectives on the outcomes of neonatal and perinatal intensive care explored the following questions: How should the need for health care resources in the neonatal and perinatal area be objectively determined? When there are competing needs between the maternal-newborn area and other areas, how should these be rationalized? What evidence should be used (or should be available) to support the present use of resources? What evidence should be available (or is needed) to change or introduce new uses of resources? The conclusions indicated that there are no generally accepted methods to determine the allocation of health care resources but that considerations need to include population characteristics, desired outcomes, achievable results, values, ethics, legalities, cost-benefit analyses and political objectives. Information from families and adolescents who required the use of high technology and/or high cost programs will contribute individual, family and societal values that complement cost-efficacy analyses.     

含栅栏状肉芽肿样小体(巨菊形团)的低度恶性纤维肉瘤--报道1例转移病例

自Ｌａｎｅ等 1997年详细报道了ＨＳＣＴＧＲ后 ,一直没有该肿瘤转移潜能的证据 ,该文报道 1例 2 8岁女性右上臂三角肌内ＨＳＣＴＧＲ(8 7ｃｍ× 5 5ｃｍ× 4 0ｃｍ大小 ) ,术后 4年右肺转移 ,并于 6年后行肺部手术 ,取出 0 6ｃｍ～ 1 2ｃｍ大小转移性结节 3枚。肿瘤从大体形态到超微结构及免疫组化表现与前文相似。本文总结出该病光镜下由梭形细胞为主 ,构成 3种图像 :①纤维瘤样区 ,为肿瘤的主要成分 ,无核分裂象 ;②细胞区 ,细胞丰富 ,核浓染 ,胶原减少 ,罕见核分裂象 ;③特征性病变 (有诊断意义 ) ,即由丰富细胞核环绕的玻璃样变小体 …