Medical phlebitis. A rational approach of the etiological evaluation

One-hundred and four records of ambulatory deep venous thrombosis were studied retrospectively to determine the usefulness of an aetiological evaluation based on a rational approach. Among these 104 patients, 27 were known to have a cancer at the time of admission, and 77 had a presumably idiopathic deep venous thrombosis. The discovery of 10 cancers in the second group (13 percent) confirmed that the aetiological research was useful. Statistical analysis of the two populations and the different parameters of the thrombus and its course failed to show any significant difference in the patients whose cancer was revealed. The aetiological evaluation pointing to the diagnosis was always simple and not very costly; it consisted of careful physical examination with vaginal and/or rectal palpation, standard laboratory tests, X-ray films of the chest and abdomino-pelvic ultrasonography. Although these cancers were at an advanced stage when discovered, the aetiological research was justified by the finding of a few tumours amenable to curative surgical treatment.     

Laboratory testing in the evaluation of male infertility. A rational approach

Alpha radiation dosage is an important occupational health factor in the mining of uranium and mineral sands. Alpha radiation induced errors in the data of silicon based memory chips provide the foundation for a new type of sensor, with the potential for affordable and prompt measurement of personal alpha doses. With particular reference to Dynamic Random Access Memories (DRAM) this paper introduces the operating principle of a memory based radiation sensor, which is the error mechanism in silicon integrated circuits.     

Nonparametric one-way multivariate analysis of variance: A computational approach based on the Pillai-Bartlett trace.

Demonstrates a method for computing the omnibus test statistic, which illustrates the relation of nonparametric methods to parametric MANOVA, based on K. Pillai's (1955) and M. Bartlett's (1939) trace statistic. The required test statistic is equal to (N?–?1)V, where V is the trace statistic computed on the transformed data. The test statistic can be obtained by submitting the data, already converted to ranks or normal scores, to a packaged MANOVA program. (25 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Fidelity of DNA ligation: a novel experimental approach based on the polymerisation of libraries of oligonucleotides

Complete libraries of oligonucleotides were used as substrates for Thermus thermophilus DNA ligase, on a M13mp18 ssDNA template. A 17mer primer was used to start a polymerisation process. Ladders of ligation products were analysed by gel electrophoresis. Octa-, nona- and decanucleotide libraries were compared. Nonanucleotides were optimum for polymerisation and up to 15 monomers were ligated. The fidelity of incorporation was studied by sequencing 28 clones (2268 bases) of nonanucleotide polymers, 12 monomers in length. Of the ligated monomers, 79% were the correct complementary sequence. In a total of 57 (2.5%) mispaired bases, there was a strong bias to G.T, G.A, G.G and A.G mismatches. Of the mismatches, 86% were found to be purines on the incoming oligonucleotide, of which 71% were G. There is evidence for clustering of mismatches within specific 9mers and at specific positions within these 9mers. The most frequent mismatches were at the 5'-terminus of the oligonucleotide, followed by the central position. We suggest that sequence selection was imposed by the ligase and not just by base pairing interactions. The ligase directs polymerisation in the 3' to 5' direction which we propose is linked to its role in lagging strand DNA replication.     

Oligodendrogliomas. Part II: A new grading system based on morphological and imaging criteria

Myocardial perfusion scintigraphy is a noninvasive diagnostic method for the evaluation of patients with suspected or proven coronary artery disease (CAD). We utilized case-based reasoning (CBR) methods to develop the computer-based image interpretation system SCINA which automatically derives from a scintigraphic image data set an assessment concerning the presence of CAD. We compiled a case library of 100 patients who underwent both perfusion scintigraphy and coronary angiography to document or exclude the presence of CAD. The angiographic diagnosis of the retrieved nearest neighbor match of a scintigraphic input case was selected as the CBR diagnosis. We examined the effects of input data granularity, case indexing, similarity metric, and adaptation on the diagnostic accuracy of the CBR application SCINA. For the final prototype, sensitivity and specificity for detection of coronary heart disease were 98% and 70% suggesting that CBR systems may achieve a diagnostic accuracy that appears feasible for clinical use.     

The Foundations of Bioethics by H. Tristram Engelhardt Jr.: comments on James F. Drane''s review

Protection of the kidney is fundamental during the treatment of abdominal aortic aneurysms (AAA). This applies particularly in patients with a renal transplant, the artery of which has been implanted on an iliac artery. Reviewing 27 AAA in patients with a renal transplant, the authors discuss the various techniques used. The authors disagree with renal function preservation methods. To maintain perfusion during clamping, different types of bypasses have been described: axillo-femoral, the Gott aortofemoral shunt or a partial extracorporeal perfusion (Campbell). With local or total hypothermia, the clamping time can be lengthened and this is used particularly when an end-to-end anastomosis into the internal iliac artery has been carried out. Since the Lacombe 1986 publication, no renal protection has been carried out for the sake of the technical needs of an operation. To reduce relative ischemia time, either the blood flow in the aortic bifurcation is maintained during the aortic clamping and the fashioning of the proximal anastomosis, or the distal anastomoses are fashioned first (Mathey), thus ensuring sufficient flow into the kidney through the collateral anastomoses between the iliacs, or by combining the 2 techniques (Mellière). The risk of infection in these immuno-depressed patients is discussed and it is concluded that the simultaneous repair of an AAA and the performance of a renal transplantation (Cerilli) is not recommended because of the risk of sepsis.     

A non-invasive technique for 3-dimensional assessment of articular cartilage thickness based on MRI. Part 2: Validation using CT arthrography

Established methods for the measurement of articular cartilage thickness are invasive and cannot be sequentially applied in living subjects. In the present study, the distribution of cartilage thickness throughout entire joint surfaces was determined from MR images obtained with a fat-suppressed gradient-echo sequence at a resolution of 0.31 x 0.31 x 2.00 mm3, and compared to that derived from CT arthrography. A minimal distance algorithm was employed to produce 3D cartilage thickness maps of seven cadaveric human knee joints. The mean amount of deviation of the cartilage volumes was 5.6% (+/- 4.6), statistical analysis showing that there was high agreement between the two methods (r = 0.995, slope = 1.037, y-intercept = -90.5 mm3). The 3D thickness maps yielded a striking agreement between the two methods, the maximum values generally yielding a deviation of none or one thickness interval of 0.5 mm. This investigation shows that accurate 3D assessment of articular cartilage thickness can be performed with MRI, this technique having the advantage that it is suitable for investigating living subjects.     

Behavioral interventions in resource conservation: A systems approach based on behavioral economics.

Outlines some of the advantages of an integration of psychological (social-learning) and economic conceptualizations when developing behavioral interventions in resource conservation. The procedures and results of rebate studies in residential energy and water conservation are presented in which rebates were used as a method to modify conservation behaviors and to estimate experimental price elasticity in contrast to the usual econometric methods. A meta-analysis is performed on behavioral energy studies conducted from 1973 to 1980, which shows that the effectiveness of rebates and feedback is partially explained by an economic factor. Also reviewed are field-based studies designed to modify perceptions of comfort and residential energy conservation in addition to the development of a rebate system instituted to reduce domestic water consumption. Maximization theory is offered as an integrative, conceptual framework that may be useful for planning resource conservation interventions. (49 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Surface modification by means of laser melting combined with shot peening: A novel approach

Among the available laser applications laser surface melting has turned out to be a powerful technique for the production of wear-resistant layers. Despite the advantages of this process, laser surface melting results in tensile stresses which may assist crack propagation. In this paper it will be shown that shot peening can overcome this drawback effectively. It turned out that a preceding laser treatment of an eutectic aluminium-silicon alloy is able to amplify considerably the effectiveness of the shot peening treatment. In particular the maximum attainable hardness and compressive stress increase upon increasing the quench rate, i.e. upon increasing the laser scan velocity. The high concentration of silicon in solid solution turned out to be the main reason for the enhanced mechanical performance, not only directly through solid solution hardening, but also by precipitation hardening and by a higher dislocation density. The latter contribution is affected indirectly by a changed cross slip behavior.     

Production of a sintered alloy based on the TiAl intermetallic compound: Part 2. Investigation into forming and sintering processes

A complex production technology of electrodes from the powder alloy based on titanium aluminide TiAl, which includes the stages of fabrication of the powder alloy by calcium hydride reduction, treatment of the powder in a ball hard alloy mill with the addition of Y₂O₃ as a structural modifier, and the hydrostatic formation and sintering of a billet, is proposed. Formation and sintering processes are investigated for experimental samples and the alloy microstructure is investigated at all stages of process flowchart. The electrode for the plasma centrifugal spraying of the granules is fabricated using this technology.     

A study of the factors in hip replacement dislocation. Part 2

Dislocation is a dramatic and distressing common complication following total hip replacement. The first article describing this study, published last week, considered some of the factors thought to predispose to dislocation. The authors emphasised the multifactorial nature of hip replacement dislocation and in this second article they examine the factors relating to acetabular position and orientation, and femoral component placement.     

The role of iron in the formation of porosity in Al-Si-Cu-based casting alloys: Part II. A phase-diagram approach

The mechanism by which iron causes casting defects in the AA309 (Al-5 pct Si-1.2 pct Cu-0.5 pct Mg) may be related to the solidification sequence of the alloy. Superimposing calculated segregation lines on the liquidus projection of the ternary Al-Si-Fe phase diagram suggests that porosity is minimized at a critical iron content when solidification proceeds directly from the primary field to the ternary Al-Si-βAl₅FeSi eutectic point. Solidification via the binary Al-βAl₅FeSi eutectic is detrimental to casting integrity. This hypothesis was tested by comparing the critical iron content observed in the standard AA309 alloy to that of a high-silicon (10 pct Si) variant of this alloy.     

A test of a theory of anxiety about body integrity: Part 2.

Kolhberg (1966) suggested that uncertainty about body integrity was more plausibly explained by cognitive factors than by the psychoanalytic theory of castration anxiety. This hypothesis leads to the prediction that children who understand the concept of anatomical constancy would show less anxiety in relation to threats to the body's integrity than children who have not yet attained the concept. The results of this study are not consistent with Kolhberg's cognitive developmental prediction. Additionally, the results of this study also reveal significant relationships between children's level of anxiety in response to threats to the body's integrity and age (or stage of development). Those subjects showing the highest level of anxiety were in the 3 to 5-year-old age group, the period referred to by psychoanalysts as the phallic period. This finding is consistent with the prediction derived from Freudian psychosexual theory which posits that 3- to 5-year-old children would be particularly sensitive to threats to the integrity and unity of their bodies. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

A novel phospholipase A2 inhibitor with leucine-rich repeats from the blood plasma of Agkistrodon blomhoffii siniticus. Sequence homologies with human leucine-rich alpha2-glycoprotein

The phospholipase A2 (PLA2) inhibitor PLIbeta, purified from the blood plasma of Chinese mamushi snake (Agkistrodon blomhoffii siniticus), is a 160-kDa trimer with three 50-kDa subunits; and it inhibits specifically the enzymatic activity of the basic PLA2 from its own venom (Ohkura, N., Okuhara, H., Inoue, S., Ikeda, K., and Hayashi, K. (1997) Biochem. J. 325, 527-531). In the present study, the 50-kDa subunit was found to be glycosylated with N-linked carbohydrate, and enzymatic deglycosylation decreased the molecular mass of the 50-kDa subunit to 39-kDa. One 160-kDa trimer of PLIbeta was found to form a stable complex with three basic PLA2 molecules, indicating that one basic PLA2 molecule would bind stoichiometrically to one subunit of PLIbeta. A cDNA encoding PLIbeta was isolated from a Chinese mamushi liver cDNA library by use of a probe prepared by a polymerase chain reaction on the basis of the partially determined amino acid sequence of the subunit. The cDNA contained an open reading frame encoding a 23-residue signal sequence followed by a 308-residue protein, which contained the sequences of all the peptides derived by lysyl endopeptidase digestion of the subunit. The molecular mass of the mature protein was calculated to be 34,594 Da, and the deduced amino acid sequence contained four potential N-glycosylation sites. The sequence of PLIbeta showed no significant homology with that of the known PLA2 inhibitors. But, interestingly, it exhibited 33% identity with that of human leucine-rich alpha2-glycoprotein, a serum protein of unknown function. The most striking feature of the sequence is that it contained nine leucine-rich repeats (LRRs), each of 24 amino acid residues and thus encompassing over two-thirds of the molecule. LRRs in PLIbeta might be responsible for the specific binding to basic PLA2, since LRRs are considered as the motifs involved in protein-protein interactions.     

Antagonists of the platelet P2T receptor: a novel approach to antithrombotic therapy

The platelet P2T receptor plays a major role in platelet aggregation, and its antagonists are predicted to have significant therapeutic potential as antithrombotic agents. We have explored analogues of adenosine triphosphate (ATP), which is a weak, nonselective but competitive P2T receptor antagonist. Modification of the polyphosphate side chain to prevent breakdown to the agonist adenosine diphosphate (ADP) and substitution of the adenine moiety to enhance affinity and selectivity for the P2T receptor led to the identification of 10e (AR-C67085MX), having an IC50 of 2.5 nM against ADP-induced aggregation of human platelets. Compound 10e was the first very potent antagonist of the P2T receptor, with a selectivity for that subtype of the P2 receptor family of >1000-fold. Further modification of the structure produced compound 10l (AR-C69931MX) having an IC50 of 0.4 nM. In vivo, at maximally effective antithrombotic doses, there is little prolongation of bleeding time (1.4-fold), which is in marked contrast to the 5-6-fold found with GPIIb/IIIa antagonists.     

一种基于参数化形状函数的拉矫工艺模型化新方法

板带平直度和表面质量是生产高品质冷轧金属板带的主要因素。拉矫机(例如应用于连续热镀锌或精整生产线)通过板带较小的弹塑性变形,改善板带的平直度,降低残余应力,产生大张力,使板带在小直径辊系中被弯曲。在拉矫机的设计过程中,精确的模型是非常重要的,它可改进主要的参数,如板带的弯曲线,弯辊的反作用力,要求的张力等级,张力损耗(由于弹性变形引起的损耗)和传动功率需求。拉矫工艺的广延分析通常采用商用的有限元软件包进行,需要对底层物理效应和相互关系全面了解。然而,高达数百万的自由度需要有效的和可靠的三维有限元模拟,这导致运行时间太长而不可接受,甚至是对于现代大型机计算。为了减少大量的三维有限元模型计算成本(同时确保更多有意义的计算结果),开发了一个基于虚功原理和参数化形状函数的全新的、专业化的模型化方法,用于描述曲率和应变分布。相较于优化的有限元模型,这种度身订造的模型可以大幅减少自由度和计算成本,而关键的模拟结果却是相同的。由于这种方法的有效性和可靠性,此方法可用于在拉矫机设计阶段大规模的参数计算,包括优化工艺和设备,改善设备性能和显著减少能耗。     

Sedation in dentistry. Part 2: Management of the gagging patient

Erythromycin, an antibiotic commonly used topically in the treatment of acne, is unstable in solution. The stability is influenced by the pH and by the presence of water. The influence of the pH on the stability of erythromycin was investigated even with the use of dimethyl isosorbide as co-solvent instead of water. The addition of zinc was attempted to ameliorate erythromycin stability as suggested in the literature. To investigate these three factors and their interactions, an optimization technique was carried out consisting of a 2(3) factorial analysis and a rotative central composite design. The erythromycin solutions were analysed with an HPLC method. The pH and the concentration of dimethyl isosorbide had a significant influence on the stability of erythromycin but the addition of zinc was not a significant factor. Moreover, there was a significant interaction between the pH and dimethyl isosorbide.     

Systemic lupus erythematosus. Part 2: The role of the nurse

The second article in this series of two describes the aims of patient education, and gives an overview of the implementation and evaluation of the patient education programme in the authors' department. It focuses on what patients can do to help prevent lupus flares and how they can develop coping skills in dealing with the day-to-day problems which often face these patients. It highlights the fundamental role of the nurse specialist as a resource in providing patient education and reflects a combined approach in the overall management of patients suffering with systemic lupus erythematosus.     

A novel recirculating reactor for the leaching of magnesia by CO2

A novel slurry recirculating reactor was designed to selectively leach caustic-calcined magnesia into soluble magnesium bicarbonate with CO₂ as the leaching reagent. Compared with the reactor without slurry recirculating, the leaching rate of magnesia could be enhanced by 80%–90% in this reactor. Parameters including mass concentration of the magnesia slurry, flowrate of slurry recirculating, injection rate of CO₂ and temperature were studied with respect to their effects on the leaching kinetics. A fast leaching of caustic-calcined magnesia could be achieved with a high CO₂-consuming efficiency of 65–70% in this reactor.     

Stereochemical variations on the colchicine motif. Part 4. A remote metalation approach toward a colchicine analog with a five-membered B-ring

Attempts to prepare a colchicine analog with a 5-membered B-ring by remote metalation of N,N-diethyl-3,4,5-trimethoxy-2-(5'-methoxy-4'-oxo-2', 5',7'-cycloheptatrienyl)-benzamide (2) led to ring contraction of the methoxytropone ring to the p-methoxycarbonylphenyl derivative (3). Dynamic 1H NMR investigations showed that the biaryl amide 2 exists as a mixture of diastereomers due to hindered rotation around both aryl-aryl and aryl-amide bonds, with rotational barriers of ca. 63 kJ mol-1. The colchicine and allocolchicine analogs 2 and 3 do not notably affect tubulin polymerization, despite the structural similarities with active analogs. The reduced tubulin binding activity of 2 and 3 may be a result of increasing steric bulk.