Radiographic quantification of alveolar bone level changes

The "random burst" theory has recently been proposed as an explanation of the pattern of periodontal disease progression. The theory predicts that the progression of bone loss at individual sites is not dependent upon previous bone loss and age. A longitudinal radiographic study was designed to test this hypothesis, and to describe the changes in bone level over 2 years in a group of 180 subjects (18-68 years of age) who were not under systematic periodontal treatment. The results indicated that 94% of the sites did not show significant changes in the alveolar bone level during the observation period. The mean annual bone loss for the total population was 0.11 mm. By regressing longitudinal bone loss upon age, it was shown that the rate of bone loss increased rapidly between 33 and 56 years of age while a different pattern was shown for the age intervals 18-32 and 57-68 years. Also, the rate of bone loss increased with increasing initial bone loss. This was less evident in the oldest age group. It was concluded that the progression of bone loss in the present material is consistent with a "burst" theory. However, the progression did not occur randomly with regard to previous loss of alveolar bone and time.     

周围神经损伤后免疫系统变化的动物实验观察

目的 :检测周围神经损伤后免疫系统的变化。方法 :用 MTT法检测了坐骨神经损伤 1 ,2 ,5,7和 1 4d的大鼠脾细胞 NK活性及淋巴细胞转化功能 ,并用 PEG沉淀法检测了大鼠血清中循环免疫复合物 (CIC)的含量。结果 :坐骨神经损伤后 7和 1 4d大鼠脾细胞的自发转化率较对照组 (同样手术应激但无坐骨神经损伤 )略有增高 ;循环免疫复合物的含量术后 7d明显增高 ,1 4d时增加明显 ;而 NK活性则无明显变化 ,后期变化如何尚待进一步研究。结论 :周围神经损伤后 ,机体发生了免疫变化。     

残胃贲门癌切除、空肠“9”字袢代胃及幽门重建术12例

目的探讨残胃贲门癌手术切除,消化道重建的方法。方法总结1989年8月至1999年12月12例残胃贲门癌切除、空肠“9”字袢代胃及幽门重建术的治疗经验。结果无手术死亡,无倾倒综合征,无返流性食管炎。钡剂在“9”字环内有循环,下方重建凼门处有钡荆停留。全组均随访,随访时间最长4年3个月,最短4个月。其中1年内死亡2例,1～2年死亡4例,2～3年死亡2例,另4例生活良好。结论术后并发症少,有抗返流作用,利于营养支持,病人生活质量较高。     

Adverse childhood experiences and the development of Down syndrome regression disorder

Down syndrome regression disorder (DSRD) is a clinical symptom cluster of acute or subacute neurocognitive regression in otherwise health persons with Down syndrome. The objective of this study was to evaluate if adverse childhood experiences (ACEs) were more prevalent in children with DSRD than those with DS alone. A survey-based, cohort-based study was performed. Caregivers of individuals with DSRD with onset of symptoms between age 10 and 30 years and DS alone were administered the ACEs questionnaire via an online REDCap survey. A total of 159 responses were collected after excluding incomplete surveys and those not meeting criteria for DSRD. Individuals with DSRD were not more likely to experience ACEs (p = 0.18, 95% confidence interval [CI]: 0.43–1.17). In those with ACEs prior to the onset of symptoms, the median time prior was 7 months (interquartile range: 5–10). Individuals with DSRD were more likely to report three or more ACEs (52, 33%) compared to those with DS alone (39, 22%) (p = 0.02, 95% CI: 1.08–2.87). Exposure to ACEs were not predictive of response to particular therapeutic interventions although those with multiple ACEs 3 months prior to the onset of symptoms was associated with lower response rates to benzodiazepines and immunotherapy (p = 0.02, 95% CI: −3.64–−1.13). This study provides preliminary data that individuals with DSRD experience ACEs at a similar rate to individuals with only DS alone, although three or more ACEs, often preceding the onset of symptoms, was more prevalent in individuals with DSRD.     

Evolution of coronary stenoses is related to baseline severity--a prospective quantitative angiographic analysis in patients with moderate coronary disease

A correlation of the angiographic evolution of coronary stenoses(stenosis diameter 20%) with morphological stenosis parametersat baseline could help to identify the risk of progressive stenoses.Therefore, the data of the prospective INTACT study (InternationalNifedipine Trial on Antiatherosclerotic Therapy) were reviewed.In 348 patients with moderate coronary artery disease, standardizedcoronary angiograms were taken 3 years apart and were quantitativelyanalysed. Changes in the minimal diameter of the 1063 preexistingcoronary stenoses compared between both angiograms were setin relation to a number of conventional stenosis parametersat baseline. Regression analysis demonstrated a significantcorrelation of the changes in minimal diameter with baseline% diameter stenosis (r=0.30; P<0.001), minimal diameter (r=—0.28;P<0.001) and reference diameter of stenoses (r=–0.14;P<0.001). The changes were not correlated with stenosis lengthand plaque area. The baseline parameters of 22 preexisting stenosesprogressing to occlusions differed from those remaining patentonly with regard to the % diameter stenosis (43 ± 9%vs 39 ± 11%; P<0.05). Additional progression of coronarydisease became manifest through development of 228 stenosesand 19 occlusions at arterial sites free from definitive stenosesin the baseline angiograms. Thus, progression of atherosclerosis predominantly occurredin mild preexisting coronary stenoses and developed at previouslyangiographically normal sites. Since the conventional angiographicparameters analysed in this study failed to identify individualarterial sites with an increased risk for progression, definitionof new angiographic parameters or application of new techniquesseem mandatory to this end.     

Arthrogryposis,renal dysfunction and cholestasis syndrome: Report of five patients from three Italian families

We report on five patients from three families with neurogenic arthrogryposis, cholestasis and tubular renal dysfunction. Despite a similar clinical picture the liver histology showed a broad pathological spectrum, ranging from pigment storage to parenchymal giant cell transformation and ductopenia. The findings are compared with those of other cases from the literature in search of a correct nosology of the syndrome characterized by arthrogryposis, renal and liver disease.Conclusion We propose to consider the picture of arthrogryposis, renal tubular dysfunction and cholestasis as a single syndrome.     

A novel strategy for the isolation of defined pyrG mutants and the development of a site-specific integration system for Aspergillus awamori

A homologous gene transfer system for Aspergillus awamori for site-specific integration is described, based on two components. First, a defined A. awamori pyrG mutant strain constructed by a selection strategy for gene-replacement in fungi. Second, a vector with a homologous pyrG selection marker containing a defined mutation at a site different from that of the mutations in the pyrG gene of the defined mutant strain. Defined mutation in the A. awamori pyrG gene, isolated from a genomic library by heterologous hybridisation with the A. niger pyrG gene as a probe, were introduced by specifically altering sequences at restriction sites in the coding region of the gene. After transformation of the A. awamori wild-type strain with vectors containing these mutated pyrG genes, and selection for 5-fluoro-orotic acid resistance (5-FOA^R), on the average 60% of the 5-FOA^R colonies originated from replacement of the wild-type pyrG gene by the mutated pyrG allele. After transformation of a mutant strain, carrying a mutation near the 5 end of the pyrG gene with vectors containing a mutation near the 3 end of the pyrG gene, 35% of the resulting transformants contained one copy of the vector at the pyrG locus.     

Blastic transformation of mantle cell lymphoma: genetic evidence for a clonal link between the two stages of the tumour

AIMS: The blastic variant of mantle cell lymphoma (MCL-BV) may develop through histological transformation of mantle cell lymphoma (MCL). However, the clonal link between the tumour cells of MCL and transformed MCL-BV has not been established at the genetic level. To investigate this link longitudinal molecular genetic studies have been performed in two cases of MCL that showed morphological transformation to MCL-BV. METHODS AND RESULTS: Polymerase chain reaction (PCR) and nucleotide sequence analyses of the complementary determining region 3 (CDR) of the immunoglobulin (Ig) heavy chain (H) gene were performed to identify clone-specific rearrangements. In both cases, nucleotide sequence analysis revealed common clone-specific IgH gene rearrangements in MCL and subsequent MCL-BV. CONCLUSIONS: These results provide genetic evidence for the common clonal origin of MCL and subsequently developed MCL-BV.     

Encoding of target direction and speed during visual instruction and arm tracking in dorsal premotor and primary motor cortical neurons

The encoding of direction and speed in the discharge of dorsal premotor (PMd) and primary motor (MI) neurons was studied during two-dimensional visually-instructed pursuit arm movements in which eight directions and four constant speeds were independently manipulated. Each trial consisted of equal durations of visual observation of target movement without hand movement (cue) and visual pursuit-tracking of the target with the hand (track). A total of 240 neurons was recorded from PMd and MI in two Macaca mulatta monkeys. Two classes of regression analyses were used to relate neuronal firing during the cue and track periods to direction and speed. First, the average firing from each period was fitted to target direction or speed. Period-averaged firing significantly correlated with direction more frequently in the track than in the cue period. Conversely, correlations with speed (with or without direction) were more common in the cue than in the track period. Secondly, a binwise regression evaluated the temporal evolution of firing correlations with direction and speed. Supporting the period-based results, significant binwise correlations of the discharge with speed occurred preferentially during the cue period when there was no hand movement. Prior to movement, correlations of the firing with direction became significant and continued through the movement. Both analyses demonstrated a distinct tendency for neurons to be modulated by speed information early and by direction information later. This temporal parcellation reflects both the sequential demands of the task and constraints placed on the neural computations. The early representation of target speed is hypothesized to reflect the need to calculate a 'go signal' for the initiation of movement.     

准分子激光原位角膜磨镶术后屈光回退与术中角膜床厚度的关系

目的　探讨准分子激光原位角膜磨镶术（ｅｘｃｉｍｅｒ ｌａｓｅｒ ｉｎｓｉｔｕ ｋｅｒａｔｏｍｉｌｅｕｓｉｓ ＬＡＳＩＫ） 矫治高度近视后屈光回退与术中角膜床厚度的关系。方法　对４７６ 例９３８ 只眼在我院接受Ｌａｓｉｋ 治疗的患者中,发生屈光回退的病例９６ 例,１８９ 只眼与未发生屈光回退的病例３８０ 例７４９ 只眼术中角膜床厚度及术前、术后１ ｗ ｋ 、１ 、３ 、６ ｍ ｏ 屈光状态的资料进行对比分析。结果　有屈光回退眼组比无屈光回退眼组平均角膜床厚度小;屈光回退眼组屈光回退程度（ 术后６ ｍｏ 时） 与角膜床厚度呈负相关系,上述结果经统计学检验均有显著性差异（ Ｐ ＜ ００１） ;有屈光回退眼组术后早期（１ ｗｋ） 屈光状态略成过矫,但其后屈光回退程度在０ ．５ａ 内呈加重趋势。结论　高度近视准分子激光原位角膜磨镶术中的角膜床厚度是影响术后屈光稳定性的重要因素