By A. Fedor. Auburn University, Montgomery.
Yet the effect of nature in these areas can also manifest itself in a positive way generic accutane 20mg on-line, in outstanding expressions of a special predisposition buy cheap accutane 10mg, which cannot be achieved in what Aristotle considers the usual way generic 30 mg accutane with visa, namely by force of habit (ethismos or askesis¯ ) and teaching (didache¯or mathesis¯ ) generic 5 mg accutane with mastercard. To describe this special predisposition and its expression in ‘particularly mental shrewdness’, 83 See the general statements on this theme in Eth. An illuminating example of this notion is Aristotle’s frequent reference to metaphors; see the remark in the Poetics (1459 a 5–7), ‘The most important thing is the ability to use metaphors. For this is the only thing that cannot be learned from someone else and a sign of natural genius; for to produce good metaphors is a matter of perceiving similarities’ (polÆ d mgiston t¼ metaforik¼n e«naiá m»non gr toÓto oÎte par’ llou stª labe±n eÉfu©av te shme±»n stiá t¼ gr eÔ metafrein t¼ t¼ Âmoion qewre±n stin). Other passages on this feature of metaphor (its being incapable of being taught) can be found in Rhetoric (1405 a 8) and Poet. Aristotle explains his use of the word euphuia in this passage in the Poetics (1459 a 7) by saying that good use of metaphor is based on the ability ‘to see similarities’ (to homoion theorein¯ ). This corresponds to the fact that Aristotle (as discussed above in section 2 ad Div. It seems to be this connection that enables the melancholic peritton in the areas of philosophy, politics and poetry. For to Aristotle, the principle of ‘perceiving similarities’ not only plays a part in the use of metaphor85 and in divination in sleep, but also in several intellectual activities such as induction, deﬁnition and indeed philosophy itself. This explanation is actually used in the text of the Problemata, but can also be found in several short statements in Aristotle’s authentic writings. A direct relationship be- tween bodily constitution and intelligence is for instance made in De. In this respect chapters 12–15 of the second book of the Rhetoric are of particular importance, in which the ‘ethopoietic’ effects of youth and old age and ‘noble descent’ (eugeneia) are discussed; in particular chapter 15 on eugeneia (with its clear relationship to phusis in the sense of a ‘natural predisposition’) is signiﬁcant. Melancholics are not mentioned in this pas- sage, but it demonstrates precisely the same thought structure as that used to describe melancholics: most of the people of noble descent (eugeneis) belong to the category of ‘the simple-minded’ (euteleis, 1390 b 24; cf. In this passage, similarly to the melancholic’s ‘instability’, reference is made to the quick decline of the eugeneis, either to ‘those who are by character more inclined to madness’ (examples for this are the descendants of Alcibiades and Dionysus) or to stupidity and obtuseness (belter©a kaª nwqr»thv; 1390 b 27–30). It appears that these two forms of degeneration correspond very well with both the ‘manic-passionate’ and ‘depressive-cold’ expressions of the melancholic nature in Pr. A consideration of the physiological aspect to people’s mental processes and ethical behaviour, as is done frequently in the Problemata,89 turns out 89 On this tendency of the Problemata, which is sometimes unfortunately referred to as ‘materialistic’, see Flashar (1962) 329ff. Aristotle on melancholy 167 to be an approach that Aristotle fully recognises and which he provides with a methodological foundation; it is by no means incompatible with the more ‘psychological’ approach demonstrated in particular in the Ethics, and Aristotle considers it rather as complementary. Whether the text of the chapter goes back to a treatise on melancholy that may have been part of Aristotle’s lost Problemata or whether it goes back to an attempt made by a later Peripatetic (perhaps Theophrastus)91 to systematise the scattered statements of the Master, will remain unknown. In any case, our analysis of the chapter, in particular of the author’s two different objectives, and of the prima facie disproportionate discussion of these objectives, has shown that it is possible to read the text as a deliberate attempt to explain an observation that would at ﬁrst sight be unthinkable in Aristotle’s philosophy (i. Ascription can only be based on the statement in 954 a 20–1 (erhtai d safsteron perª toÅtwn n to±v perª pur»v) and the fact that Diogenes Laertius (5. The former argument has proved to be rather weak: as Flashar (1962, 671) must admit, the statement is not really in line with Theophrastus’ writing De igne. One might point to chapter 35, but precisely at the relevant point the text of the passage is uncertain, and even if one accepts Gercke’s conjecture di¼ kaª toiaÓta qerm»tata t purwqnta kaqper s©dhrov, the parallel is not very speciﬁc (safsteron). The statement would make more sense as a reference to a lost book on ﬁre in the Problemata (see Flashar (1962) 671) or the Aristotelian treatment of heat and ﬁre in Part. Yet even if one is prepared to accept the statement as referring to Theophrastus’ De igne, there is the possibility that the Peripatetic editor/compilator of the Problemata collection is responsible for this, and it need not imply that the theory presented in the chapter is originally from Theophrastus (see Flashar (1956) 45 n. These terms correspond to Aristotle’s usage, whereas the word melagcol©a reminds one either of the Hippocratic names for melancholic diseases (for instance Airs, Waters, Places 10, 12; 52, 7 Diller) or of Theophrastus’ theory on character. This way, the explanation of the anomalia¯ and the variety of expressions of the melancholic nature serves to answer the chapter’s opening question, which at the end should not look quite so un- Aristotelian (and indeed no longer does) as at the start. Finally, this chapter should hopefully provide a starting-point for a re- newed testing of the working hypothesis that those parts of the Problemata that have been passed on to us can be used as testimonies of Aristotle’s views, on the understanding that these passages do not contradict the authentic texts. These occurrences do not really seem to contradict the statements made by Aristotle (perhaps with the exception of 860 b 21ff. However, only an in-depth analysis of these at times very difﬁcult passages can more clearly deﬁne the precise relationshipwithAristotle’sconcept. For a rather sceptical view on the working hypothesis see Flashar (1962) 303 and 315. As a result, dreams were mostly approached with caution because of their ambiguous nature. The Greeks realised that dreams, while often presenting many similarities with daytime experiences, may at the same time be bizarre or monstrous. This ambiguity gave rise to questions such as: is what appears to us in the dream real or not, and, if it is real, in what sense? What kind 1 perª d tän tekmhr©wn tän n to±sin Ìpnoisin Âstiv ½rqäv gnwke, meglhn conta dÅnamin eËrsei pr¼v panta, On Regimen 4. For general surveys of Greek thought on dreams see van Lieshout (1980) and Guidorizzi (1988); for discussions of early and classical Greek thought on sleep see Calabi (1984), Marelli (1979–80) and (1983), Wohrle (¨ 1995) and Byl (1998). In the ﬁfth and the fourth centuries bce we can see a growing concern with the nature of dreams and with the kind of information they were believed to provide among philosophers (Heraclitus, Plato, Democritus), physicians (such as the Hippocratic author just quoted), poets (Pindar) and historians (Herodotus). In this context of intellectual and theoreti- cal reﬂection on the phenomenon of dreaming, Aristotle’s two works On Dreams (Insomn. At the same time, Aristotle’s style in these treatises is characteristically elliptical, and they present numerous problems of inter- pretation. In this chapter I will of course say something about the contents of this theory and its connection with other parts of Aristotle’s work; but the emphasis will be on the methodology which Aristotle adopts in these writings. First, I will deal with how Aristotle arrived at his theory, with particular consideration of the relation between theoretical presuppositions and empirical observations in both works. We know that Aristotle in his biological works often insists on the importance of collecting empirical evidence in order to substantiate ‘theories’ or ‘accounts’ (logoi) of nature. He sometimes takes other thinkers to task for their lack of concern with empirical corroboration of their theories, or he even accuses his opponents of manipulating the facts in order to make them consistent with their theories. My second question concerns the ratio underlying Aristotle’s treatment, especially the selection of topics he deals with and the order in which they are 5 For a translation with introduction and commentary of these works see van der Eijk (1994); see also Pigeaud (1995); Gallop (1996) (a revised edition of his ); Dont (¨ 1997); Morel (2000); Repici (2003). For although Aristotle, within the scope of these short treatises, covers an admirable amount of topics and aspects of the phenomenon of dreaming with a sometimes striking degree of sophistication, it is at the same time remarkable that some important aspects of dreaming are not treated at all – aspects which are of interest not only to us, but also to Aristotle’s contemporaries. Nor does he pay serious attention to the interpretation of dreams: he only makes some very general remarks about this towards the end (464 b 9–16); he does not specify the rules for a correct interpretation of dreams. Yet the meaning of dreams was what the Greeks were most concerned with, and we know that in Aristotle’s time there existed professional dream interpreters who used highly elaborated techniques to establish the meaning of dreams. This lack of interest calls for an explanation, for not only does experience evidently suggest that these mental operations are possible in sleep, but there was also a powerful tradition in Greek thought, widespread in Aristotle’s time, that some mental operations, such as abstract thinking (nous), could function better and more accurately in sleep than in the waking state, because they were believed to be ‘set free’ in sleep from the restrictions posed by the soul’s incorporation in the body. Now, in response to this, one could argue that Aristotle was under no constraint from earlier traditions to discuss these points, for early and clas- sical Greek thought tends to display rather ambivalent attitudes to the phenomenon of sleep, and in particular to whether we can exercise our cognitive faculties in sleep. On the one hand, there was a strand in Greek thought, especially in some medical circles, in which sleep was deﬁned negatively as the absence of a number of activities and abilities that are characteristic of the waking life, such as sense-perception, movement, con- sciousness and thinking. And as we shall see in a moment, Aristotle’s theory of sleep shows strong similarities to this tradition. On the other hand, there was also a strand in Greek thought, represented both in Orphic circles but 8 See del Corno (1982). These experiences and impulses can be subdivided into stimuli that have their origin within the dreamer and those that come from outside. The external stimuli can in their turn be subdivided into two categories: those that have their origin in the natural world, and those that come from the supernatural (gods, demons, etc. A similar, related ambivalence surrounded the question whether the sleeping life of an individual presents a complete negation of the character and personality of his/her waking life, or whether there is some connection or continuity between the two states. It would seem that if one deﬁnes sleep negatively (as Aristotle does) as an incapacitation of our powers of consciousness, the consequence would be that in the sleeping state the characteristics of our individual personalities are somehow inactivated: it would be as if, in sleep, we lose our identity and temporarily become like a plant. Yet, paradoxically, this negative view also allowed a positive valuation of the state of sleep. For it can be argued that in sleep our souls or minds are released from our bodies (and from experiences associated with the body, such as perception and emotion) and acquire a temporary state of detachedness and purity, thus anticipating the state of the immortal soul after its deﬁnitive detachment from the body after death. This latter view – that in sleep the soul is set free from the body and regains its ‘proper nature’ (idia phusis) – was especially found in Orphic and Pythagorean thought, with its negative view of the body and its dualistic concept of the relation between soul and body, and found its expression in stories 9 See Aristotle, Insomn. Aristotle on sleep and dreams 173 about ‘ecstatic’, clairvoyant experiences such as told about Hermotimus of Clazomenae and other ‘shamans’. For, at other places in his work, Plato seems to allow that our sleeping lives somehow reﬂect our mental state in the waking life. Thus in a well-known passage in the Republic, he suggests that dreams reﬂect an individual’s spiritual state in that they show whether the soul is calm and orderly, guided by reason, or subjected to emotions and desires: (I mean) those desires that are awakened in sleep, when the rest of the soul – the rational, gentle, and ruling part – slumbers. Then the beastly and savage part, full of food and drink, casts off sleep and seeks to ﬁnd a way to gratify itself.
An ability to record blood pressure variation in addition to heart rate changes during sym ptom s w ould be a very helpful and exciting addition to the investigation of people w ith syncope cheap accutane 5 mg. Arrhythm ias detected by am bulatory m onitoring; lack of correlation w ith sym ptom s of dizziness and syncope cheap accutane 40mg free shipping. Increm ental diagnostic yield of loop electrocardiographic recorders in unexplained syncope accutane 30mg online. Detection of arrhythm ias; use of patient-activated am bulatory electrocardiogram device w ith a solid state m em ory loop cheap accutane 30 mg with amex. Simon Sporton Norm al activation of the ventricles below the bundle of His occurs by w ay of three “fascicles” – the right bundle branch and the anterosuperior and posteroinferior divisions of the left bundle branch. There have been no random ised trials of pacing vs no pacing in patients w ith chronic bi- or trifascicular block. Clinicians m ust therefore be guided by know ledge of the natural history of the condition w ithout pacing, and expert consensus guidelines. The largest prospective study of patients w ith bi- and tri- fascicular block follow ed 554 asym ptom atic patients for a m ean of 42 m onths. The five year m ortality from an event that m ay conceivably have been a bradyarrhythm ia w as just 6% , a figure that m ust inevitably include som e non-bradyarrhythm ic deaths. An im portant finding of this study w as a five year all cause m ortality of 35% reflecting the high incidence of underlying coronary heart disease and congestive cardiac failure. The available evidence w ould suggest that asym ptom atic patients w ith trifascicular block should not be paced routinely. A history of syncope should prom pt thorough investigation for both brady- and tachyarrhythm ic causes. If interm ittent second or third degree block is docum ented perm anent pacing is indicated. Bi- and trifascicular block are associated w ith a high incidence of under- lying coronary heart disease and heart failure. Attention should 100 Questions in Cardiology 165 therefore be directed tow ards the detection of these conditions and the use of therapies know n to im prove their prognosis. Dual cham ber pacing (or m ore accurately physiological pacing w hich m ay include single cham ber atrial devices) is the preferred m ode in m ost com m on indications for pacem aker im plantation. Physiological pacem akers can be recom m ended in sinus node disease on the basis of m any retrospective studies and one prospective study. M ortality is m inim al and occurs due to unrecognised pneum othorax, pericardial tam ponade or great vessel traum a. Com plications at im plant are those of subclavian puncture, particularly pneum othorax, although these can be avoided if the cephalic approach is used. There is som e long term evidence that the cephalic approach m ay avoid chronic lead failure in polyurethane leads due to subclavian crush injury. Acute lead displacem ent should be less than 1% for ventricular leads and 1–2% for atrial leads. Prospective random ised trial of atrial versus ventricular pacing in sick-sinus syndrom e. Alistair Slade Pacem akers have increasingly sophisticated circuitry to prevent dam age or interference from external m agnetic interference. Electric fences Nobody should touch an electric fence but should electric shock occur it w ould be w ise to have the system checked by form al interrogation in case electrical m ode reversion has occurred. Significant artefact w ould be obtained in regions close to an im planted pacem aker but m ore im portantly the pow erful m agnetic fields m ight interfere w ith the device. Airport metal detectors Airport m etal detectors have the potential to interfere w ith pacing system s. Patients should produce their pacem aker registration cards to bypass busy security queues. M obile phones M obile phones have been extensively investigated in term s of interaction w ith im planted devices. Analogue phones do not interact w ith im planted devices but m ore m odern digital devices have the potential to interfere w ith pacing system s w hen utilised w ithin a field of 10–15 cm. Pacem aker patients w ith m obile phones are therefore advised to carry m obile telephones on the opposite side 100 Questions in Cardiology 169 of the body from the site of the device im plant and should hold the device to the opposite ear. Safe perform ance of m agnetic resonance im aging on five patients w ith perm anent cardiac pacem akers. Alistair Slade Patients w ith pacem akers often require cardioversion, particularly w ith the increasing use of pacing techniques in the m anagem ent of paroxysm al atrial fibrillation. The decision regarding this should be m ade on an individual basis, depending on the type of pacem aker, reason for im plant, and pacing-dependency. Patients needing cardioversion should have the paddles applied in a m anner such that the electrical field is rem ote from the pacem aker electrical field. In practise the standard apex— sternum approach is safe w ith a pacem aker in the left shoulder region, although anteroposterior paddle positioning can be utilised. The low est energy possible should be adm inistered, and the pacem aker should be checked form ally after the procedure as occasionally the pacem aker m ay change m ode as a consequence of cardioversion. Efforts should be m ade to ensure that, during synchronised shock, the defibrillator is recognising the ventricular, and not atrial, pacing spike. M odern system s have increasingly effective protection from external interference. An arrhythm ia is usually although not invariably a sign of underlying heart disease. This is an im portant consideration because treatm ent of the underlying condition, w here possible, is likely to be m ore effective than antiarrhythm ic drug therapy both in term s of preventing the arrhythm ia and im proving prognosis. Conversely, if treatable underlying heart disease rem ains untreated then antiarrhythm ic drug therapy is unlikely to be successful. This m ay reflect a lack of efficacy and/or toxicity of currently available anti- arrhythm ic agents. The decision to im plant is easier if there is a history of presyncope or syncope. Im proved survival w ith an im planted defibrillator in patients w ith coronary artery disease at high risk for ventricular arrhythm ia. Simon Sporton Consideration of the electrophysiological disturbances pre- disposing to the developm ent of torsade de pointes provides a logical approach to m anagem ent. Experim ental and clinical evidence im pli- cates abnorm al prolongation of cardiac action potential as a critical factor. Under these conditions early after-depolarisations m ay occur and lead to repetitive discharges (“triggered activity”). Hypokalaem ia and hypo- m agnesaem ia are w ell recognised causes of torsade although the evidence for hypocalcaem ia is less convincing. Bradycardia – either sinus or due to atrioventricular block – is an im portant contributory factor. W here the brady- cardia is due to atrioventricular block atropine is unlikely to increase the ventricular rate. Transvenous ventricular pacing should be established rapidly although it is alm ost certainly w ise to stabilise the patient first w ith an isoprenaline infusion (at a rate of 1-10m icrogram s/m in, titrated against the heart rate) or external cardiac pacing. There is experim ental and clinical evidence to support the use of intravenous m agnesium in the acute treatm ent of torsade. A dose of 8m m ol (adm inistered over 10-15 m inutes) has been show n to abolish torsade in the m ajority of patients although a second dose m ay be necessary. There is no evidence to support the use of either intravenous potassium or calcium. The serum concentration of these electrolytes is frequently disturbed as a result of cardiac arrest per se and a reasonable strategy w ould be to obtain a form al laboratory m eas- urem ent after a period of haem odynam ic stability and to correct as 174 100 Questions in Cardiology necessary. There is no role for conven- tional antiarrhythm ic drugs in the m anagem ent of torsade de pointes: on the contrary m any antiarrhythm ics m ay aggravate the situation. T w ave m orphology should also be carefully exam ined, in particular for high takeoff, late onset, broad base, bifid m orphology w ith hum ps, and beat-by-beat alternating polarity (T w ave alternans). Holter m onitoring should be perform ed to exclude repetitive ventricular arrhythm ias of the torsade de pointes type. In Rom ano-W ard syndrom e (1/20,000 births: autosom al dom inant transm ission w ith >90% penetrance), 50% of offspring of one affected parent are predicted to be sim ilarly affected. Six associated genetic loci (on chrom osom es 3, 4, 7, 11, 21, 22) have been identified, of w hich four relate to genes that encode cardiac ion-channel proteins.
The authors state that an easily cleanable nonporous material is the preferred upholstery in hospitals discount accutane 20mg with amex. The effectiveness of decontamination of the environment depends on the method used cheap 5mg accutane free shipping. In one study trusted 40 mg accutane, the investigators observed that cleaning environmental surfaces with a cleaning rag sprayed with a quaternary ammonium disinfectant was significantly less effective than dipping the cleaning rag into a bucket of the same disinfectant accutane 30 mg otc, drenching all surfaces, allowing the surfaces to remain wet for 10 minutes, and then wiping the surfaces dry with a clean towel (177). Using the method in which the disinfectant was sprayed on the cleaning rag took 2. Based on this study, the bucket method is the preferred method for decontaminating environmental surfaces. In another study investigators examined the elements of environmental cleaning to determine whether changes in cleaning products, cleaning procedures, or performance of cleaning personnel would lead to more effective cleaning of the environment (178). The authors noted that the performance of cleaning personnel was the most important factor in the effective decontamination of the environment. The effectiveness of cleaning personnel performance was related to the number of environmental sites cleaned. After patient contact, hands should be washed with an antiseptic-containing soap or an alcohol hand rub should be applied. Six studies on the use of piperacillin–tazobactam in place of third-generation cephalosporins and ticarcillin–clavulanate have been published (181–186). However, there were several significant differences between the two groups and the authors did not apply multivariable analysis to obtain a clearly un- confounded conclusion of their results. 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