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Assessment of Liver Transplant Donor Biopsies for Steatosis Using Frozen Section: Accuracy and Possible Impact on Transplantation
Background: Pre-transplant frozen section evaluation for macrovesicular steatosis has long been used as a guide for donor liver utility, but may not agree with the permanent section evaluation. This study sought to evaluate the accuracy of frozen section in an active transplant service. Methods: Retrospective review of cases where frozen section analysis was undertaken to assess percent macrovesicular steatosis was performed, comparing the frozen section diagnosis to the final diagnosis. Results: Ninety-six cases were available for review. In 7 of these cases (7%), the difference between the two slides was significant; that is, the difference between the two slides may have contributed to a change in clinical management at a cutoff of 30%. Conclusions: Clinicians need to be aware that accuracy is satisfactor
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Author's response: influenza-associated mortality oseltamivir: beware of misstepping into stepwise procedures.
We thank Lytras et al. [1] for the comments on our recent article assessing risk factors for mortality in inpatients with influenza and the effect of oseltamivir [2]. For this study, the authors are confident that the identification and adjustment for confounding variables have been done in a systematic and objective manner using stepwise logistic regression. We note the concerns on the methods we have used, but we do not see how these concerns are specific to our work. Rather the concerns relate in general to the application of these methods.Addenbrooke's Charitable Trus
Original Article
Tetrodotoxin, a toxic substance obtained from the globe fish, has been known to paralise the neuromuscular system as well as the central nervous system and recently, it was found to block production of the action potential through its selective inhibition of the sodium-carrying mechanism, but has no effect on the resting potential. In this paper, the effects of tetrodotoxin on the four kinds of skeletal muscle fibers were compared and analysed. Four muscle fibers are tonic and phasic fibers of the extrafusal muscle, and nuclear-bag and nuclear-chain fibers of the intrafusal muscle fibers. The extrafusal muscle is a dynamic source of posture and locomotion, the intrafusal muscle being the regulating source of them. Paralysis of the extrafusal muscle fibers was determined by measuring the decrease in maximum contraction of the soleus (tonic muscle) and tibialis anterior (phasic) produced stimulation of the distal cut end of the ventral root. Paralysis of the intrafusal muscle fibers wasmeasured by a change in the frequency of Group la discharge led from the functionally isolated single filaments of the distal cut end of the dorsal root. By intravenous administration of 4γ/kg tetrodotoxin, paralysis advaces beginning with the intrafusal muscle fibers, and then on to the tonic muscle and phasic muscle fibers. They recover according to the same order. When the intrafusal muscle fiber recovers during an advance in paralysis of the extrafusal muscle, intrafusal muscle fibers contract by the γ-efferent activated by stimulation of the ventral root, and the Group la discharge increases. Frequency of the Group la discharge increases in proportion to muscle extension, therefore the contraction curve of the intrafusal muscle fiber is measured from augmentation of the discharge frequency. Contraction of the intrafusal muscle fibers lasts for several hundred msec, and the curve has two peaks at about 60 msec, and 110 (Fig. 5).It is clear then that the former corresponds to contraction of the nuclear-bag fiber, and the latter to contraction of the nuclearchain fiber
Original Article
Die Kategorie der sog. Schizophrenie kann heute noch nur unscharf begrenzt werden. Daher habe ich als Forschungsmaterial nur die Falle gesammelt, welche reine schizophrene klinische Bilder zeigen; u. zwar sind die verdachtigen Falle, die am Randteil oder im Grenzgebiet dieses Krankheitsbegriffs liegen mogen, streng ausgeschlossen. Die Studie ist uber die Anamnesen von 161 Fallen gemacht, die ich selbst in diesen 6 Jahren behandelt habe, und besonders sind die objektiven, durch die Krankenfamilien beobachteten-d. h. mit Augen der Nichtfachmanner bemerkte-befunde des Krankheitsbeginns genau erforscht. Die Resultate der statischen Untersuchung sind folgende. A. Uber die Falle von Kerngruppe der Schizophrenien, welche im jungeren Alter unter 30 Jahren ausbrechen und zur sog. katatonen oder hebephrener Form gehoren, ist es gelungen, einige Regeln auszuziehen, wodurch die Eigentumlichkeiten der initialen psychrotischen Anzeichen und die Beziehungen zwischen den Entwicklungsweisen der Symptome, die Arten der Krankheitsbilder, die Verlaufsformen u. s. w. bestimmt werden. B. Es ist moglich, einige Anzahl vom Typen des Krankheitsausbruchs darzustellen. 1) Die obenerwahnte Kerngruppe kann in (a) 5 besondere Formen, welche deutliche Eigenschaften zeigen, und (b) 4 typische Formen klassifiziert werden. 2) Die sonstigen Falle werden in (a) 2 Typen vom typischen Beginn, deren Krankheitsausbruch doch im mittleren Alter ist, und (b) 4 mehr seltene Formen, die ganz atypische Ausbruchsweisen zeigen, eingeteilt
Original Article
It has been the general practice to employ culture methods in discerning whether Ascaris eggs are alive or dead. Although culture methods are most reliable, they are not without shortcomings- -the time required in going through the procedures is very long. The discovery of some reliable and simple methods, therefore, has eagerly been awaited. However little research has been done on this subject and no better methods have ever been developed. Sudan III staining method is one of the methods developed so far, but its reliability is doubted by many researchers. In an effort to devise a new staining method, the author carried out a series of experiments; sudan III staining method was first checked on the attempts were made to enhance the ability of eggs to stain by pre-treating them with acid and alkali, and finally a number of dyes, especially fatty dyes, were experimented on. As a result of these experiments, the author has developed anew staining method using Lugol\u27s solution and has proved that it is superior to sudan III staing method. Further experiments were carried out in order to investigate into the mechanism of staining. A comparative study of this method with the staining method using fluoroscopic dye, which had recently been developed, was also performed. The results of the experiments are summarized as follows: 1. The eggs killed by heating stained well by sudan III staining method, but the eggs killed by other means did not stain well. Attemts were made to enhance the ability to stain by applying various pre-treatment but without success. 2. The live eggs stained with Lugol\u27s solution are not decolorized by alcohol, but the dead eggs stained with Lugol\u27s solution are decolorized by alcohol. It would thus be possible to discern by this method whether eggs are dead or alive. Although it has no absolute value, this method is superior to sudan III staining method and is availabe for experimental purposes.3. It seems that the permeability of the egg-shell plays an important part in Lugol\u27s solution staining method. Although results vary with the change in the methods used for killing eggs, it seems that the permeability of shells of eggs are enhanced when they are dead, thereby promoting decolorization. 4. It is assumed that it is the .third layer that plays a significant role in the permeability of the eggshell. 5. It seems that the staining method using fluoroscopic dyes, which has more or less similar value as sudan III staining method, is inferior to Lugol\u27s .solution staining method in discerning whther Ascaris eggs are dead or alive
Original Article
Phosphodiesterase specific for the hydrolysis of diphenylphosphate, one of aromatic phosphodiesters, was obtained from hog kidney by following procedure. To hog kidney homogenized in a Waring blendor with 3 volumes of distilled water was added solid sodium chloride to a final concentration of 1% and after adjusting of pH to 5 with ca. 5 N hydrochloric acid, it was shaken for 10 minutes with an equal volume of n-butanol, allowed to stand for one hour, and centrifuged. The aqueous extract present beneath the floating gel layer of protein and butanol mixture, was siphoned out and fractionated with ammonium sulfate. The precipitate obtained between 45 and 70 % saturation was dissolved in a small volume of distilled water, dialyzed for 48 hours against running tap water, and then, to inactivate the monoesterase, heated in water bath of 100° for 5 minutes, whereby the solution became faintly turbid. The enzyme solution, thus prepared, hydrolyzed diphenylphosphate, liberating phenol but no inorganic phosphate, while it was inactive to monophenylphosphate. Diphenylphosphate of a final concentration of 0.0005M could be hydrolyzed in one hour at the optimum pH 7 to the extent of 40%. At this pH, the enzyme activity was not influenced by addition of Mg^, Ca^, or CN^. Bis-dichloroisopropylphosphate, dibenzylphosphate, diethylphosphate, lysolecithin, RNA, and DNA were resistant to this enzyme. It is conceivable that these diesters are hydrolyzed by other enzymes different from the aromatic phosphodiesterase, presented in this paper
Original Article
The present paper deals with an investigation on the changes appearing in the mucous membrane of the nose (physiologic atrophy) in normal persons of different age groups, as contrasted with a wasting of the mucous mambrane of the nose in cases of atrophic rhinitis. The investigation has been performed for the purpose of contributing to the studies of the pathology of atrophic rhinitis. 1. Pathologic changes of a considerable degree were. observed in the epithelium in quite a large section of infants and children where it had been considered normal as a results of macroscopic examinations. 2. Metaplasia of the epithelial cells developing in the mucous membrane in the forepart of the respiratory region seems to occur as a result of the stimulus applied from without. The phenomenon was marked in the front and along the lower edge of the inferior turbinal, showing a tendency to increase in magnitude as the age advance. It did not, however, spread over a wide area, nor was there any marked development of cornification. An increase in mucus secretion, as well as in the number of goblet cells, was noticed in the epithelium as the age advance. Mucous degeneration gradually set in at the end of forties, becoming marked in the sixties. 4. In the basal membrane, the hyaline layer, which is its secondary form, grew in size with age, and a substance which stains with Hale\u27s stain was detected in it. This substance seems to have an important share in the mucus secreting function of the epithelium. 5. It seems that the epithelium of the mucous membrane of the upper respiratory tract continues to function even in considerably advanced ages. 6. The lymphoid tissue situated underneath the epithelium attained the largest quantity in persons about 20 years old; it began to diminish and grow less thick in persons over 40. The presence of the elastic fiber was noticed in the subepithelial layer in all age groups, though the number of persons with this phenomenon was small.7. The glands wers under-developed in children of about 10; they grew rapidly after that age until about 40 when they began to show a tendency to atrophy. 8. It seems that the periglandular lymphocytes, which infiltrate without bringing about the disintegration of the glands, take charge of the metabolism of the glands. A large number of them were found in infancy but they showed a marked decrease in number in persons over about 40. It would seem that, in highly advanced ages, non-inflammatory disintegration of the glands could possibly occur as a result of the infiltration of the lymphoid tissue. 9. The formation of the oncocyte, an unusual cell of the epithelium of the gland which characterizes the old age, was noticed in 7 cases. 10. The blood vessels manifested changes of a high degree in persons of advanced ages: they revealed evidences of functional disturbance of a high degree when stained by the stains of H. E, Weigert, PAS and Hale. This would show the measure of the influence that has been exerted on the function of the mucous membrane. 11. Corpora cavernosa was under-developed in infancy but became well-developed in persons of about 20; a decrease in the number of bodies and a diminution in size of the inner lumen became marked in persons over 40, becoming more marked in persons over 50
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