Longitudinal relationship between incisal tooth wear and periodontal condition

The purpose of the study was to examine the relationship between the longitudinal development of incisal tooth wear and periodontal conditions in 51 persons. Stone casts obtained at the ages of 15 and 27 yr were used to assess incisal wear according to a graded scale, the Incisal wear Index (Iwl). The wear increase after 12 yr, ΔIwI, was related to the various health index scores at the age of 15 yr, including the Plaque Index (PII) and Gingival Index (GI) systems. The chi-square tests showed a statistically significant association between AIwI and periodontal condition in 15-yr-olds. Thus, relatively low P1I and GI values were accompanied by relatively high AIwI values. It was concluded that in 15-yr-olds, P1I and GI levels are clinical predictors of future wear (ΔIwI) of maxillary and mandibular central incisors. Pocket depth (PD) was a less valuable clinical predictor of such wear.     

Prediction of severe postoperative complications in patients admitted to neuroanaesthesia

The purpose of this study was to identify factors which will predict the risk of severe postoperative complications in individual patients in a neurosurgical unit. Eleven risk factors were investigated in 363 neurosurgical patients, of whom 40 (11%) developed postoperative complications requiring mechanical ventilation for more than 24 h in an intensive care unit, 16 were found to be severely disabled or in a vegetative state at follow-up 1 month after admission, and 28 patients died. By applying stepwise, logistic regression analysis to the patient's data, we were able to select two significant risk variables, i.e. the Glasgow Coma Scale (GCS) 8 or less preoperatively and emergency anaesthesia. The presence of GCS 8 or less on the consciousness scale was associated with postoperative complications in approximately 40% of the cases. Emergency patients with severe neurological damage had the greatest risk of postoperative complications (93%). Fatal outcome for patients with postoperative complications was seen in 40% of the cases.     

Direct injections of calcitriol into enlarged parathyroid glands in chronic dialysis patients with severe parathyroid hyperfunction

Summary: Severe secondary hyperparathyroidism in chronic dialysis patients has been recently treated by supraphysiological concentration of calcitriol achieved through pulse therapy. However, there are many patients resistant to this therapy, who usually have larger parathyroid gland(s). to overcome this resistance, calcitriol was injected directly into the enlarged glands under ultrasonographic guidance. We injected 70–90% of the calculated gland volume of calcitriol solution (1 μg/mL) into the glands of 7 patients three times per week for 2 weeks. the parathyroid hormone (PTH) levels decreased significantly after 2 weeks of direct injections of calcitriol. Following a further 4 weeks of calcitriol pulse therapy, PTH levels remained suppressed and serum alkaline phosphatase activity and the volume of parathyroid glands also decreased. During the long-term follow up, five patients remained well controlled with calcitriol pulse therapy, while two patients needed ethanol injections to control hyperparathyroidism. Although we could not completely rule out a toxic effect of the vehicle, direct injection of calcitriol into parathyroid glands may be another treatment option for chronic dialysis patients. Our data further support the important role of resistance of parathyroid cells to calcitriol in the pathogenesis of parathyroid hyper function in uraemic patients.     

Reduction of Mortality in the Stockholm Ischaemic Heart Disease Secondary Prevention Study by Combined Treatment with Clofibrate and Nicotinic Acid

Consecutive survivors of a myocardial infarction from the Southern Hospital, below 70 years of age, were randomized into a Control group (n=276) and a Treatment group (n=279). The latter was openly prescribed the combination of clofibrate and nicotinic acid for serum lipid lowering. Each patient should remain in the study for 5 years and be seen regularly every 4 months at a special IHD outpatient clinic within the hospital. The concentration of serum cholesterol and triglyceride was lowered by 13% and 19%, respectively, in the Treatment group compared to the Control group. Total mortality was 82 cases in the Control group and 61 in the Treatment group, a 26% reduction (p<0.05). For patients above 60 years of age in the Treatment group the reduction in mortality was 28% (p<0.05). IHD mortality was reduced by 36% (p<0.01)in the Treatment group compared to the Control group. The beneficial effect of the serum lipid lowering treatment was related to the serum triglyceride concentration in two ways. First, it only occurred in patients with a triglyceride level >1.5 mmol/l (n=216). Secondly, it was most pronounced in the 44% of the treated patients who had a lowering of the serum triglyceride concentration by 30% or more, and in this subgroup the reduction of IHD mortality was 60% (p<0.01). For serum cholesterol there were no such relations. The difference between serum triglycerides and cholesterol concerning these relations to the treatment outcome may be due to the fact that hypertriglyceridaemia was the most common hyperlipidaemia among our patients, occurring in 50%, while hypercholesterolaemia only occurred in 13 %. Caution should be exercised in the interpretation of the results as the trial was not blind. However, the fact that the decrease in IHD deaths was directly related to the degree of serum triglyceride lowering indicates that it was the drug effect on serum lipids that was reponsible for the beneficial effect of the treatment.     

Structure and conformation of linear peptides XII. Structure of tryptophanyl-glycyl-glycine dihydrate

The crystal structure of a tripeptide, tryptophanyl-glycyl-glycine dihydrate (C₁₅H₁₈N₄O₄·2H₂O, molecular weight = 354) has been determined. The crystals are orthorhombic, space group P2₁2₁2₁ with a= 7.875 (1) A,b= 9.009(1), c= 24.307(1) and Z = 4. The final R-index is 0.058 for 1488 reflections ((sin θ/λ≤ 0.6 A^?1) with I < 2σ(I). The molecule exists as a zwitterion, with terminal NH⁺₃ and COO^? groups. The peptide units are trans and nearly perpendicular to the plane of the carboxyl group. The backbone torsion angles are: ψ₁= 132.7°, ω₁= 174.2°, φ₂ 88.2°, ψ= 8.6°, ω₂ - 179.8°, φ= - 85.2°, ψ₃₁, = - 178.1°, ψ₃₂ 5.0°. For the sidechain of tryptophan, χ₁= - 171.6°, χ₂ 101.0°.     

Structure and conformation of peptides involving prolyl residue III. L-Prolyl-L-isoleucine monohydrate

The dipeptide, L-prolyl-L-isoleucine monohydrate (C₁₁ H₂₀N₂O₃· H₂O, molecular weight 246.3) crystallizes in the monoclinic space group P2₁, with a = 6.601(3)Å, b = 5.413(3) Å, c = 19.128(6) Å, β= 98.1(1)°, Z = 2, Do = 1.20g·cm^-3 and Dc = 1.208g·cm^-3. The structure was solved by MULTAN–80 and refined to a final R-factor of 0.081 for 594 reflections measured on a Enraf Nonius CAD-4 diffractometer. The peptide linkage exists in the trans conformation. The pyrrolidine ring is disordered with two alternate envelope conformations for the C^γ atom. The values of the sidechain torsion angles are: χ₁₁=– 63.6(17)°, χ₁₂= 171.1(16)° and χ₂=– 59.6(21)° for isoleucine (C-terminal). The crystal structure is stabilized by a three-dimensional network of N—H ? O, O—H ? O and C—H ? O hydrogen bonds. The dipeptide exists in the extended Conformation.     

Short utterance recognition using a network with minimum training

A feedforward network is used to recognize short, digitized, isolated utterances. A high, multispeaker recognition rate is achieved with a small vocabulary with a single training utterance. This approach makes use of the pattern recognition property of the network architecture to classify different temporal patterns in the multidimensional feature space. The network recognizes the utterances without the need of segmentation, phoneme identification, or time alignment. We train the network with four words spoken by one single speaker. The network is then able to recognize 20 tokens spoken by 5 other speakers. We repeat the above training and testing procedure using a different speaker's utterances for training each time. The overall accuracy is 97.5%. We compare this approach to the traditional dynamic programming (DP) approach, and find that DP with slope constraints of 0 and 1 achieve 98.5% and 85% accuracies respectively. Finally we validate out statistics by training and testing the network of a four-word subset of the Texas Instruments (Tl) isolated word database. The accuracy with this vocabulary exceeds 96%. By doubling the size of the training set, the accuracy is raised to 98%. Using a suitable threshold, we are able to raise the accuracy of one network from 87% to 98.5%. Thresholding applied to all networks would then raise the overall accuracy to well over 99%.

This technique is especially promising because of the low overhead and computational requirements, which make it suitable for a low cost, portable, command recognition type of application.     

继发性骨质疏松防治的研究

目的总结继发性骨质疏松预防与治疗的经验及提出见解.方法用钙代谢平衡的方法研究了钙代谢的基本情况,比较了补钙与不补钙在若干种生理状态对骨密度的影响,总结继发性骨质疏松的病因及对其采取不同方法的治疗经验.结果中国人膳食含钙量属于正常范围低水平状态,与适宜摄入量(AI)比较是不足的,在一定的生理状态下应予补钙.缺钙是原发性骨质疏松与继发性骨质疏松的不利因素.氟中毒骨病、糖尿病、性腺功能减退、肿瘤、糖皮质激素过多和甲亢均有其各别的病理生理,导致继发性骨质疏松,防治方法各异.结论从胚胎至老年都应防治骨质疏松.不同情况采取方法各异,但有效.     

The universal algorithm of maturation for secretory and excretory protein precursors.

During maturation, most proteins undergo different posttranslational modifications. In most simple cases, signal peptidases remove the signal or leader peptide from the precursors of the secretory proteins during their translocation across the ER membrane. For biologically active proteins, such as enzymes, regulatory and defense proteins, toxins, etc., additional maturation-regulating mechanisms were shown to proceed with limited proteolysis of inactive precursors by specific enzymes. A number of specific enzymes from different cell types selectively cleave proproteins at specific processing sites. In this work, we analyzed the sequences of protein precursors synthesized in the excretory glands of different animals and identified new, non-traditional processing sites. They differ from the motifs previously identified in secreted proteins' precursors and enabled us to reconstruct the sequence of events leading to the conversion of protein precursors into the final products (mature proteins). We also found that in animals, the maturation mechanism of secretory and excretory proteins and the set of enzymes involved are species specific. The processing sites identified in protein precursors in this study are useful for a more detailed genome analysis and more accurate mature protein sequence prediction.