Technical note: A blind test of mandibular ramus flexure as a morphologic indicator of sexual dimorphism in the human skeleton

Loth and Henneberg (1996, Am. J. Phys. Anthropol. 99:473–487) identified a single morphological feature of the mandible, the presence or absence of a distinct flexure or angulation of the posterior margin of the mandibular ramus at the level of the occlusal plane, which appears to be an extraordinarily accurate predictor of sex. Using only this feature, Loth and Henneberg were able to predict sex with 94% accuracy in a large sample of mandibles. In this article, we report the results of a blind test of mandibular ramus flexure as a predictor of sex. In our blind test, only 62.5% of the mandibles were correctly sexed, and virtually identical results were obtained when the same sample of mandibles was examined by a second observer. Overall, our results demonstrate that: 1) the association between ramus flexure and sex is weak; 2) the predictive accuracy of Loth and Henneberg's method is better than chance for only one sex, males; and 3) the method is based on a trait that cannot be reliably or consistently identified. Am J Phys Anthropol 107:363–366, 1998 © 1998 Wiley-Liss, Inc.     

Placebo controls: historical, methodological and general aspects

Control conditions were introduced through the trial of Mesmerism in Paris. Placebo controls became codified standard in 1946. Although seemingly unchallenged, there are various problems with this received view. The notion of a placebo is only defined from the negative. A positive notion proposed that placebo effects are effects owing to the meaning an intervention has for an individual. Thus, placebo effects are individualized, whereas standard research paradigms reveal only grossly averaged behaviour. Also, placebo effects are context sensitive, dependent on psychological factors such as expectancy, relief of stress and anxiety, and hence can generate strong and long-lasting treatment effects. These, however, are not predictable. Such a situation can lead to the efficacy paradox: sometimes, sham interventions can be more powerful than proved, evidence-based treatments. This situation has methodological consequences. Placebo-controlled randomized trials reveal only part of the answer, whether an intervention is effective. This is valuable information for regulators, but not necessarily also for patients and of limited value for providers. Hence, I have argued that we need to complement the hierarchical model of evidence by a circular one, in which various methods are employed on equal footing to answer different questions.     

The effect of n-3 polyunsaturated fatty acids on leukotriene B₄ and leukotriene B₅ production from stimulated neutrophil granulocytes in patients with chronic kidney disease

The proinflammatory leukotriene B₄ (LTB₄) may be of importance in the progression of chronic kidney disease (CKD). We investigated whether n-3 polyunsaturated fatty acids (PUFA) decrease LTB₄ and increase the formation of the less inflammatory leukotriene B₅ (LTB₅) in patients with CKD.Fifty-six patients with CKD stage 2-5 were randomised to 2.4 g n-3 PUFA or olive oil for 8 weeks. Compared to controls, n-3 PUFA significantly decreased release of LTB₄ (p<0.001) and 5-hydroxyeicosatetraenoic acid (5-HETE) (p<0.01) and significantly increased release of LTB₅ (p<0.001) and 5-hydroxyeicosapentaenoic acid (5-HEPE) (p<0.001) from stimulated neutrophil granulocytes. Kidney function evaluated by creatinine clearance and proteinuria did not improve. In conclusion, n-3 PUFA supplementation for 8 weeks in patients with CKD stage 2-5 significantly decreased LTB₄ and 5-HETE and significantly increased LTB₅ and 5-HEPE. No effect was seen on kidney function.     

Structural and energetic requirements for a second binding site at the dimeric β-lactoglobulin interface

Through experimental and theoretical approaches, it has been shown that bovine β-lactoglobulin (βlg) uses its hydrophobic cavity or calyx as the primary binding site for hydrophobic molecules, whereas the existence of a second ligand binding site at the dimeric interface has only been structurally identified for vitamin D3 (VD3). This binding exists even in the thermally denatured state, suggesting the prevalence of this secondary site. Although crystallographic experiments have suggested that VD3 can bind to both monomeric and dimeric states without significant structural differences, theoretical and experimental reports have proposed some structural requirements. Thus, in this study, based on known experimental data, the dynamic interaction of VD3 with the monomeric or dimeric forms of βlg was investigated through a protocol combining blind docking and 2 microsecond molecular dynamics simulations coupled with binding free energy and per-residue binding free energy decomposition analyses using the Molecular Mechanics Generalized Born Surface Area approach. Binding free energy calculations allowed us to estimate the energetic differences of coupling VD3 at the calyx and the dimeric interface for the monomeric or dimeric state, revealing that the dimeric structure is required to form a stable complex with VD3 at the dimeric interface. This also has an important impact on the dimerization process, whereas although the monomeric state also forms a stable complex with VD3 at the dimeric interface, the incorporation of the entropy component contributed to producing a marginally favorable binding free energy. Finally, the per-residue decomposition analysis provided energetic information about the most relevant residues in stabilizing the different systems.     

降纤酶治疗急性脑梗死的双盲对照研究

目的　观察降纤酶治疗急性脑梗死的效果。　方法　降纤酶与安慰剂治疗进行了随机双盲对照研究。　结果　治疗组第 1 4天神经功能缺损程度的评分低于对照组 ,P <0 .0 5 ,有显著性差异。两组出院时与 1 2周患者日常生活能力 ,即 Barthel指数计分比较 :对照组出院时与 1 2周相比 ,P <0 .0 5 ,有显著性差异 ;治疗组出院时与 1 2周相比 ,P <0 .0 1 ,有显著性差异 ;对照组与治疗组二者相比 ,P <0 .0 5 ,亦有显著性差异 ,表明治疗组患者日常生活能力的改善优于对照组。纤维蛋白原含量动态观察表明 :用药前和第 2天相比变化不大 ,P >0 .0 5 ;第 4天纤维蛋白原开始下降 ,P <0 .0 5 ;第 6天维持在第 4天水平 ,第 4天和第 6天相比 ,P >0 .0 5。通过对用药前后谷丙转氨酶 ( GPT)和尿素氮 ( BUN)的动态观察表明 ,降纤酶对 GPT有降低趋势 ,对 BUN无任何影响 ,本组全部病例均未见全身出血倾向或致颅内出血之并发症发生。治疗组死亡 1例 ,死亡原因系心房纤颤 ,急性肺水肿引起的呼吸循环衰竭 ,死亡前患者神经系统症状体征无变化 ,与应用降纤酶无关。　结论　降纤酶有明显降低纤维蛋白原 ,改善微循环的作用 ,对肝肾无害 ,也未见其它并发症。由于它纯度高及特异性的与血栓表面的纤维蛋白原结合 ,因此 ,避免了尿激酶、链激酶     

Adjunctive subantimicrobial dose doxycycline in the management of institutionalised geriatric patients with chronic periodontitis

Objective: To assess the efficacy of subantimicrobial dose doxycycline (SDD; 20 mg doxycycline twice daily) as an adjunct to scaling and root planing (SRP) in the treatment of moderate‐severe chronic periodontitis (CP) in institutionalised elderly patients aged 65 years or older. Background: Previous studies have shown that SDD is of clinical benefit in the treatment of CP. However, the benefits of SDD in geriatric populations (65+ years) have not been determined. Material and methods: A 9‐month, double‐blind, randomised, placebo‐controlled pilot study was conducted. 24 institutionalised geriatric patients (65 years or older) with evidence of CP manifested by baseline clinical attachment levels (CAL) 5–9 mm, probing depths (PD) 4–9 mm and bleeding on probing (BOP) were recruited. At baseline, patients were treated by a standardised episode of SRP, and randomised to receive either adjunctive SDD or placebo. Full mouth PD and CAL were measured using the manual UNC‐15 periodontal probe at 3, 6, and 9 months post‐baseline to assess the response to treatment. Periodontal sites were stratified by baseline PD value: sites with PD 4–5 mm were considered moderately diseased and sites with PD ≥6 mm severely diseased. Results: The SRP + placebo resulted in PD reductions similar to those reported previously in the literature. At all time‐points and in both moderate and deep sites, SRP + SDD resulted in significantly greater PD reductions relative to baseline than SRP + placebo. At month 9, in moderate sites, mean PD reductions of 1.57 ± 0.11 mm were reported in the adjunctive SDD group, compared with 0.63 ± 0.11 mm in the adjunctive placebo group (p < 0.001). In deep sites at month 9, mean PD reductions of 3.22 ± 0.29 mm were reported in the adjunctive SDD group, compared with 0.98 ± 0.31 mm in the adjunctive placebo group (p < 0.05). Similar improvements were observed for CAL in the SDD group compared with the placebo group. Significantly lower BOP scores were also recorded at month 9 in the SDD group (7.5%) compared with the placebo group (71.2%) (p < 0.01). Conclusion: SDD used as an adjunct to SRP provides significant benefit for elderly patients with CP compared with SRP alone.     

A second species of the genus Sciaphyes (Coleoptera: Leiodidae: Cholevinae: Sciaphyini) from Japan

A second species of the genus Sciaphyes Jeannel is reported from Japan. The new species, S. kawaharai sp. n., can be easily distinguished from other Japanese Cholevine by the lack of eyes and hind wings. S. kawaharai sp. n. was collected in the nests of lesser white-toothed Shrew, Crocidura suaveolens (Pallas 1811) (Insectivora: Soricidae), therefore its habitat is pholeophile.