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A new method for measurement of femoral anteversion. A comparative study with other radiographic methods.

A new biplanar method of measuring femoral anteversion, which may be considered a modified Magilligan's method, is described. In addition to the true antero-posterior radiograph, a true translateral radiograph is taken, instead of a transcervical lateral radiograph as in the Magilligan method. The acute angles (alpha and gamma) between the long axes of the shaft and neck of the femur on both the antero-lateral and lateral radiographs are measured. The angle (gamma') of anteversion is obtained by the trigonometric formula; tan gamma' = tan/tan alpha. The femoral anteversion in 20 adult dried femora and 40 femora in 20 children was measured by the Magilligan method, the authors' method and the conventional CT method. Compared with direct measurement in the dried femora, it was found that both the Magilligan and the authors' methods tended to overestimate and the CT method tended to underestimate (p < 0.05) the anteversion. In children's femora, a similar trend was observed among the three methods and the measurements by each method differed significantly from the other (p < 0.05). We feed that our method of biplanar measurement of femoral anteversion is more accurate, although probably marginally, than the conventional Magilligan method. It also has some relative advantages in clinical application in that positioning is easier, rotation is better controlled, and less time is consumed.

Adolescent↗

Basidiomycete cryopreservation on perlite: evaluation of a new method.

A new cryopreservation method using perlite as a carrier was evaluated on a large set of mycelial cultures of basidiomycetes. The viability and some other characteristics--growth, macro- and micromorphology, and laccase production--of 442 strains were tested after 48-h and then after 3-year storage in liquid nitrogen using a perlite protocol (PP). All (100%) of them survived successfully both 48-h storage and 3-year storage in liquid nitrogen without noticeable growth and morphological changes. Also laccase production was unchanged. The viability and laccase production of a part (250) of these strains were compared with those of the strains subjected to an original agar plug protocol (OP). Using OP, 144 strains (57.6%) out of 250 survived a 3-year storage in liquid nitrogen. The results indicate that the cryopreservation protocol used significantly influences survival of the strains. Markedly better results were achieved using the PP.

Aluminum Oxide↗

Histamine-induced bronchoconstriction in conscious guinea pigs measured by strain-gauge transduction. A new method.

A new objective method for measuring histaminedihydrochloride-induced bronchoconstriction in conscious guinea pigs has been developed. The aim of the present work was to investigate whether identical results could be obtained when the clinical observation of conscious guinea pigs with symptoms of respiratory distress (bronchoconstriction) was compared to an objective measuring technique of this parameter. An evaluation of the repeatability of the method was made and the respiration frequence (fR) and histaminedihydrochloride challenge concentration were compared to see whether there was a correlation between the two. Consequently, an apparatus was built that allowed simultaneous recording of breathing pattern and clinical observation of the animal being challenged. The breathing pattern was recorded by a strain-gauge transducer, connected to a measuring bridge, and the curves obtained on a jet ink x-y writer were used for calculating changes in duration of expiratory phase (Te) and fR. During the attacks of histaminedihydrochloride-induced bronchoconstriction a significantly prolonged Te could be calculated from the respiration curves. A high degree of agreement was found between this objective measure and clinically observed respiratory distress. The repeatability of the method was comparable to that of corresponding methods used for histaminedihydrochloride challenge in man. No obvious correlation was found between changes in fR and histaminedihydrochloride challenge concentration.

Animals↗

US Environmental Protection Agency Method 326.0, a new method for monitoring inorganic oxyhalides and optimization of the postcolumn derivatization for the selective determination of trace levels of bromate.

The development of US Environmental Protection Agency (EPA) Method 317.0 provided a more sensitive, acceptable alternative to EPA Method 300.1 to be proposed as one of the recommended compliance monitoring methods for Stage II of the Disinfectants/Disinfection By-Products (DBP) Rule. This work was initiated to evaluate other postcolumn reagents (PCRs) that might be utilized to provide an additional, alternative method in order to augment compliance monitoring flexibility for inorganic oxyhalide DBP anions. Modifications of the method reported by Salhi and von Gunten, which included adjustment and optimization of flow-rates, reaction temperature, and delivery of the PCR, improved the method performance. Method 326.0 incorporates an acidic solution of potassium iodide containing catalytic amounts of molybdenum(VI) as the PCR and provides acceptable precision and accuracy for all analytes and a postcolumn bromate detection limit in reagent water of 0.17 microg/l.

Bromates↗

Analysis methods of polysorbate 20: A new method to assess the stability of polysorbate 20 and established methods that may overlook degraded polysorbate 20.

PURPOSE: Polysorbate 20 is a commonly used excipient in biopharmaceutical formulations, some of which may have an enzymatic activity. The action(s) of polysorbate 20 in biopharmaceutical formulations as a stabilizer require this surfactant to maintain its intact structure. This manuscript evaluates a new analytic method for the analysis of polysorbate 20 degradation in the format of a biopharmaceutical formulation and makes a comparison with several established methods of analysis. METHODS: Polysorbate 20 samples were degraded in a controlled environment utilizing the enzyme pancreatic lipase to generate degradants that included lauric acid and the sorbitan polyoxyethylene side chain. A new method was developed with sufficient sensitivity to analyze the degraded solutions. Lauric acid was derivatized with the fluorescent reagent 9-anthryldiazomethane to form 9-anthrylmethylethyl ester. The derivatized lauric acid was separated by reversed-phase chromatography and detected by fluorescence or UV spectroscopy. Three established methods utilized to measure polysorbate 20 were evaluated for their ability to detect degraded polysorbate 20. These methods were: (1) fluorescence analysis with N-phenyl-1-naphthylamine fluorescent dye; (2) UV spectroscopy with ammonium cobaltothiocyanate colorimetric reagent; and (3) nuclear magnetic resonance (NMR). RESULTS: Polysorbate 20 incubation with lipase resulted in degraded polysorbate 20 as determined by the derivatized lauric acid assay. The UV spectroscopy assay utilizing ammonium cobaltothiocyanate reagent was not able to detect the degradation of polysorbate 20 in the samples. The fluorescence method of analysis detected polysorbate 20 degradation as an approximate 50% decrease in micelles in comparison to standard nondegraded polysorbate 20 solutions. NMR analysis resulted in similar proton peak areas for both degraded and nondegraded polysorbate 20 samples. NMR spectra did contain minor differences between the samples. CONCLUSIONS: It is essential to choose the appropriate method of polysorbate 20 evaluation to assess the content, stability, and compatibility of a formulation. Current established methods to assess polysorbate 20 may overlook and do not necessarily monitor the potential degradation of this surfactant, which results in the formation of lauric acid. Because this type of degradation may occur in a formulation by an enzymatically active biopharmaceutical, a new method of analysis has been established.

Chemistry, Pharmaceutical↗

The cuff method: a pilot study of a new method of monitoring neuromuscular function.

BACKGROUND: A new method of monitoring neuromuscular blockade based on a modified blood pressure cuff that incorporates stimulating electrodes was compared with mechanomyography (MMG) ('gold standard'). METHODS: Forty adults and 20 children (ASA I-II) underwent neuromuscular blockade monitoring on the contralateral arms and on the same arm using the new cuff method and MMG. Only train-of-four (TOF) ratios > 0.1 and T(1) heights > 0 were studied. Supramaximal stimulation was also assessed. A device based on a PC with an analogue-to-digital conversion card was used to control and synchronize MMG and the cuff method. The agreement between both methods was assessed using the statistical method of Bland and Altman. RESULTS: When TOF ratios were >0.7, the bias between the two methods was -0.04 with the limits of agreement ranging from -0.21 to -0.12 (95% CI -0.06 to -0.02). The T(1) > 0 heights bias was -0.01 with the limits of agreement ranging from -0.26 to 0.24 (95% CI -0.02 to -0.003). The sensitivity of the cuff method was 88%, with a specificity of 85% and an accuracy of 86%. CONCLUSION: This pilot study indicates that the cuff method could be useful to monitor neuromuscular blockade according to the bias and limits of agreement compared with MMG, particularly when the degree of blockade was evaluated by TOF ratios > 0.7. The new cuff method is easy and simple to use. However, further studies in a larger number of patients are necessary to confirm these favourable preliminary results.

Adolescent↗

[The Akin-New method for surgery of hallux valgus. 1-year results of a covered surgical method].

A new technique of operation on hallux valgus according to the method of Akin (1925) was introduced to us by Dr. Theodore O. New in 1983. From small skin incisions the removal of the bunion and a corrective osteotomy of the phalanx are accomplished. The results of the operation in 72 out of a total of 77 operated feet one year after operation are reviewed. By the patients 40 (55%) of the results were judged as excellent (A), 23 (32%) as good (B) and 9 (13%) as not satisfying (C). The results of objective assessment were less favorable. 11 (15%) excellent (A) and 34 (48%) good (B) were opposed by 27 (37%) non satisfying results. These are attributed to the stringent rules of judgment and the lack of experience in suitable indications. Saving the metatarsophalangeal joint, minimal postoperative pain and early rehabilitation are advantages of this technique.

Adult↗

Modification of a model for cerebral ischemia in the cat: a new method to occlude the middle cerebral artery.

A modified method of occluding the middle cerebral artery (MCA) by inserting a tiny copper wire into the lumen of the vessel to make a model for cerebral ischemia in the cat is described. Of 22 rats, 4 were controls and the remaining 18 were divided into two groups. Bipolar electrocoagulation was used in 9 cats and copper wire insertion was used in the other 9 to occlude the MCA through a transorbital approach. Two cats died after surgery and were excluded from this study. Of the 16 cats in two experimental groups, 13 of 14 showed hemiplegia and the other 2 were killed under anesthesia. Typical ischemic changes can be seen in the territory of the occluded MCA. Increased water content and decreased amplitude of somatosensory evoked potentials can be found in the ischemic hemisphere. Histochemical fluorescence study demonstrated that the sympathetic nerve fibers normally existing on the MCA can be completely destroyed by electrocoagulation but may remain intact with the copper wire method. This new method may have less influence on the vascular regulative function of the autonomic nervous system and be more similar to the pathological changes of cerebral infarction in man. We think our method can be useful for further research in cerebral ischemic disease and the regulative effects of the nervous system on brain vessels.

Animals↗

Increased temperature of malignant urinary bladder tumors in vivo: the application of a new method based on a catheter technique.

PURPOSE: The aim of this study was to investigate the existence of any thermal difference between malignant tumors and inflammatory benign lesions of the human urinary bladder and to determine whether it correlates with tumor angiogenesis quantification. PATIENTS AND METHODS: A new method, developed in our institute, is introduced to detect temperature in human urinary bladder, in vivo. This method is based on a thermography catheter. We calculated the differences of the temperature of the solid tumor and of a normal area (Delta T) on 20 subjects (mean age, 72.5 years; 95% confidence interval [CI], 68.5 to 76.4). According to the biopsy histology, Eight (40%) patients had benign tumors, and 12 (60%) had malignant tumors. RESULTS: We found significant differences of Delta T between patients with benign and malignant tumor (P <.001). Also, differences were found for the mean values of angiogenesis level between malignant and benign tumors (P =.0261), and a moderated positive correlation was estimated between the degree of angiogenesis and Delta T (P =.02). Based on logistic regression analysis, we found that a 1-degree increase of Delta T triples the odds of a patient having a malignant tumor (odds ratio = 2.91; 95% CI, 1.97 to 7.78; P <.001), adjusted for the degree of angiogenesis (P =.0236) and the grade of tumor (P <.001). A threshold point of Delta T = 0.7 degrees C was determined, with sensitivity 83% and specificity 75%. CONCLUSION: These findings suggest that the calculated difference of temperature between normal tissue and neoplastic area could be a useful criterion in the diagnosis of malignancy in tumors of the human urinary bladder.

Aged↗

[Ureasic activity in soy products. Proposal of a new method].

The evaluation of residual ureasic activity in soy products is usually employed as an indicator of the efficiency of the inhibition treatments. The purpose of this study is to compare the AACC method (22-90), based on differences of pH, with an assay where ureasic activity is measured by its hydrolytic action on urea and quantification of the ammonium produced with Berthelot reaction. Twenty different samples of soy bean flour with and without thermal inactivation treatments were assessed with the two methods. The new method has a good correlation with that of the AACC--r = 0.9416 (p < 0.0001). It also presents a better specificity because it measures the concentration of the reaction product and shows a more amplified answer than the increase of pH.

Flour↗

[A new method of avoiding entrainment swelling in liquid surfactant membrane for the determination of trace Hg(II)].

Entrainment swelling consists of occlusion swelling and reliquefaction swelling. Entrainment swelling is significant to industrialized liquid surfactant membrane in the process of operation. The present study based on the life-span of W/O emulsion and O/W emulsion discussed the process of forming entrainment swelling. The result shows that no matter what surface-active agent was used, the life-span of W/O emulsion is 20-88 times longer than that of O/W emulsion. After oil drop was dispersed in water, no swelling was discovered, thus, the ratio of swelling is less than that by other method. The new method of determination of trace mercury by avoiding entrainment swelling in liquid surfactant membrane and FAAS is described. The precision(RSD) and recovery are 1.9%-2.3% and 99.8%-101.1% respectively. Hg2+ at ng x g(-1) level can be enriched and determined. This method can be used in the determination of trace mercury in waste water.

Emulsions↗

A new method of preparing specimens for cytodiagnosis of lung cancer.

A simple and effective method for concentrating sputum in the preparation of smears for cytodiagnosis of lung cancer was developed. The procedure, which utilizes a fixative consisting of 2,3-dihydroxy-1,4-dithiol-butane, 3,5-ditert-butyl-4-hydroxy-toluene, polyoxyethylene-cetyl-ether, polyethylene glycol 1540, and ethyl alcohol in distilled water permitted preparation of an amucoid, thin smear. Sputum was collected in a screw-cap plastic tube containing the fixative. After 12 hours mucus in the sputum was liquefied and the cellular elements were obtained from the bottom of the tube. Cellular morphology was well preserved for cytodiagnosis. Microscopic observation was facilitated by lysis of the mucus. Estimation of cellular origin was rather easy because of the distinct fixation. Cells from the sputum sediment following liquefaction were more representative of the entire specimen than with a random selection method. The new method should be useful not only in hospitals but also in mass surveys.

Adenocarcinoma↗

Two-dimensional echoencephalography with electronic sector scanning. Clinical experiences with a new method.

A new form of ultrasound diagnostic possibility is presented (the electroscan). The basic principles of this two dimensional method are described. Special attention is given to the probe consisting of an array of 21 elements of piezo-electric material. The results of this method in four patients are discussed (meningioma, arteriovenous aneurysm, subdural haematoma, and a baby with hydrocephalus). The baby with hydrocephalus showed diagnostic problems which could be understood from the pneumoencephalographic findings. The electroscan method seems to offer good possibilities for the diagnosis of brain lesions, if these have a consistency different from that of normal brain tissue.

Adult↗

[Evaluation of a new method for cervical cytology].

An adequate sample is the most important factor for successful cervical cytology. In this study a conventional method is compared to a new method of biopsy in a group of 40 patients undergoing tests in June 1991. A quantitative and qualitative evaluation of esocervical and endocervical cells was made; similar percentages were obtained for floor cells using both using systems, whereas higher percentage values (82.5% vs 67.5%) were obtained for cylindrical cells using the new method. Compared to the conventional method the new method also possessed an inadequacy rate of below 50% in post-menopausal patients. Therefore, although the new method is similar to the conventional one in terms of quality, it is thought to be more appropriate due to the greater number of endocervical cells collected, especially in post-menopausal patients.

Adult↗

Validation of three new methods for determination of metal emissions using a modified Environmental Protection Agency Method 301.

Three new methods applicable to the determination of hazardous metal concentrations in stationary source emissions were developed and evaluated for use in U.S. Environmental Protection Agency (EPA) compliance applications. Two of the three independent methods, a continuous emissions monitor-based method (Xact) and an X-ray-based filter method (XFM), are used to measure metal emissions. The third method involves a quantitative aerosol generator (QAG), which produces a reference aerosol used to evaluate the measurement methods. A modification of EPA Method 301 was used to validate the three methods for As, Cd, Cr, Pb, and Hg, representing three hazardous waste combustor Maximum Achievable Control Technology (MACT) metal categories (low volatile, semivolatile, and volatile). The modified procedure tested the methods using more stringent criteria than EPA Method 301; these criteria included accuracy, precision, and linearity. The aerosol generation method was evaluated in the laboratory by comparing actual with theoretical aerosol concentrations. The measurement methods were evaluated at a hazardous waste combustor (HWC) by comparing measured with reference aerosol concentrations. The QAG, Xact, and XFM met the modified Method 301 validation criteria. All three of the methods demonstrated precisions and accuracies on the order of 5%. In addition, correlation coefficients for each method were on the order of 0.99, confirming the methods' linear response and high precision over a wide range of concentrations. The measurement methods should be applicable to emissions from a wide range of sources, and the reference aerosol generator should be applicable to additional analytes. EPA recently approved an alternative monitoring petition for an HWC at Eli Lilly's Tippecanoe site in Lafayette, IN, in which the Xact is used for demonstrating compliance with the HWC MACT metal emissions (low volatile, semivolatile, and volatile). The QAG reference aerosol generator was approved as a method for providing a quantitative reference aerosol, which is required for certification and continuing quality assurance of the Xact.

Aerosols↗