Phisiology

Persian Father of Medicine, Avicenna (or Abu Ali Ibn Sina) and his Canon of Medicine (Arabic: القانون في الطب‎ al-Qānūn fī aṭ-Ṭibb) is an encyclopedia of medicine in five books compiled by Persian philosopher Avicenna (Ibn Sina) and completed in 1025. It presents an overview of the contemporary medical knowledge, which had been largely influenced by Galen

The Canon of Medicine remained a medical authority for centuries. It set the standards for medicine in Medieval Europe and the Islamic world, and was used as a medical textbook through the XVIII century in Europe. It is still used in Unani medicine, a form of traditional medicine practiced in India.

Book 3 is arranged from head to toe covering the function and diseases of each organ.


Book 3 is arranged from head to toe covering the function and diseases of each organ.

Los servicios de los sistemas ecológicos y las reservas naturales de capital que los producen son fundamentales para el Sistema de apoyo a la vida de la Tierra. Contribuyen al bienestar humano, tanto directa como indirectamente, y por lo tanto representan una parte del valor económico total del planeta. Hemos estimado el valor económico actual de 17 servicios ecosistémicos de los sistemas para 16 biomas, basado en estudios publicados y algunos cálculos originales. Para la biosfera entera, el valor (la mayoría de los cuales está fuera del mercado) se estima en un rango de $ 16-54 billones (10 12) por año, con un promedio de $ 33 trillones por año. Debido a la naturaleza de las incertidumbres, esto debe ser considerado como una estimación mínima. Total del producto nacional bruto es de alrededor de $ 18 billones al año.

Persian Father of Medicine, Avicenna (or Abu Ali Ibn Sina) and his Canon of Medicine (Arabic: القانون في الطب‎ al-Qānūn fī aṭ-Ṭibb) is an encyclopedia of medicine in five books compiled by Persian philosopher Avicenna (Ibn Sina) and completed in 1025. It presents an overview of the contemporary medical knowledge, which had been largely influenced by Galen.

The Canon of Medicine remained a medical authority for centuries. It set the standards for medicine in Medieval Europe and the Islamic world, and was used as a medical textbook through the XVIII century in Europe. It is still used in Unani medicine, a form of traditional medicine practiced in India.

Avicenna begins part one by dividing theoretical medicine and medical practice. He describes what he says are the "four causes" of illness, based on Aristotelian philosophy: The material cause, the efficient cause, the formal cause, and the final cause.

Material Cause Avicenna says that this cause is the human subject itself, the "members or the breath" or "the humours" indirectly.
Efficient Cause The efficient cause is broken up into two categories: The first is "Extrinsic", or the sources external to the human body such as air or the region we live in. The second efficient cause is the "Intrinsic", or the internal sources such as our sleep and "its opposite-the waking state", the "different periods of life", habits, and race.
Formal Cause The formal cause is what Avicenna called "the constitutions ; the compositions". According to Oskar Cameron Gruner, who provides a treatise within Avicenna's Canon of Medicine, this was in agreement with Galen who believed that the formal cause of illness is based upon the individual's temperament.
Final Cause The final cause is given as "the actions or functions".

In the thesis on General Physiology or "The Faculties of the Body", Avicenna separates life into three different categories: Vegetable, Animal, and Human. He contrasts Galen's view that the brain is the "chief seat of sentient life" with Aristotle's view that the heart is the source of all the body's faculties, saying that if physicians considered the matter carefully they would agree with Aristotle that the heart was the ultimate source of all the faculties, even if (for example) the brain is where the rational faculty manifests itself.

Heroism consists of actions that must help others, even if it is a possibility and risk of the helper s injury or even death. Some people consider heroism to be very close to altruism, but it is different. Where altruism emphasizes self-denying acts that help others, heroism means a personal sacrifice. The kernel of heroism rotates around of the obligation of the person to a noble goal and readiness to accept a consequence of fighting for this goal. Heroism is old as humanity itself. The human bent fort commemorating heroes is a universal quality of human culture. Heroes are honored in ancient paintings, folklore and myth. Societies dispatched such stories in oral traditions and legends, and myths into epic poems and eddas. Modern societies uphold the tradition of honoring heroes not only in literally masterpieces but also in movies and journalism. Some of heroic ideas are becoming lost or changed by general culture. Being a hero is not just being an outstanding figure. We believe it has become needful to revise the historical senses of the word, and to force it to arrive in modern timeframes. Historically, heroism has been closely connected with military service, although social heroism also deserves close research. For instance, Achilles is the archetypal war hero, whose values were so strong, that Socrates willingness to die for it was also a heroic exploit. Heroism that consist a notable idea is usually not so dramatic like heroism that entails direct physical risk. These different ways of exhorting with the heroic ideal mean a deeper, more tangled definition of heroism. Actions considered as heroic are ordinarily made voluntarily in the sense that they are not compelled by external pressures or at least go out the bounds of the behavior ordinarily prompted by external pressures. By understanding of heroism as a universal characteristic of human nature, not as an unusual feature, heroism becomes something that stands in the line of possibilities for everyone, possibly inspiring us to answer that call. The thought about the banality of heroism disrobes the myth of the heroic elect. It is a myth that strengthens two fundamental human tendencies: to attribute very rare personal feature to special people who do special feats-to see them as superhuman, comparing to the rest of us and the trap of inertial some people call it as the bystander effect. Investigation has shown that this effect is often motivated by scattering of responsibility. In their article The Banality of Heroism , Zeno Franco and Philip Zimbardo tell that heroism is made up of four autonomous measurements at least (based on authors analysis of many acts that they consider heroic). First, heroism involves some type of quest, which may range from the preservation of life to the preservation of an ideal (Franco, Zimbardo). Second, heroism should have some form of sacrifice (risk). This can be some form of physical danger or a strong social sacrifice. The physical risks in this case are clearly heroic in nature. For instance, Tom Cahill, a researcher from the University of California, called a press conference where defined the EPA s findings that in the after-grass of the September 11 events the air nearby Ground Zero was safe for breathing. With this action he risked his confidence as a scientist. Third, the heroic feat may be active or passive. Often we think of heroism as a courageous activity, something that is clearly perceptible. But some forms of heroism involve passive opposition or reluctance to be moved. And finally, heroism may be an unexpected, one time action, or something that continues over a longer time period. This may have a meaning that heroism may be a nearly immediate reaction to a situation. Or it may be a well considered series of actions endure over days, months, ANGELINO

Persian Father of Medicine, Avicenna (or Abu Ali Ibn Sina) and his Canon of Medicine (Arabic: القانون في الطب‎ al-Qānūn fī aṭ-Ṭibb) is an encyclopedia of medicine in five books compiled by Persian philosopher Avicenna (Ibn Sina) and completed in 1025. It presents an overview of the contemporary medical knowledge, which had been largely influenced by Galen

The Canon of Medicine remained a medical authority for centuries. It set the standards for medicine in Medieval Europe and the Islamic world, and was used as a medical textbook through the XVIII century in Europe. It is still used in Unani medicine, a form of traditional medicine practiced in India.

Book 2 (the Materia Medica) of the Canon alphabetically lists about 800 "simple" medical substances that were used at the time. The substances are simple in the sense of not being compounded with other substances. The first part gives general rules about drugs and a treatise on what was called "the science of powers of medicines". The second part is a list of 800 simple floral, mineral, and animal substances. Each entry contains the substance's name, its criteria of goodness (which sometimes describes how the substance is found in nature), and its nature or primary qualities. Next are listed one or more of 22 possible general actions, followed by specific properties listed according to a grid of 11 disease types. Finally, potential substitutes for the substances are given.The Canon contains seven rules for experimenting with new drugs, taken partly from Galen.
1 "The drug must be free from any acquired quality"; for example from being exposed to heat or cold or stored in close proximity to other substances.
2 "The experiment must done on a single, not a composite condition"; in other words it should not be tested on a patient who has complex or multiple illnesses.
3 "The drug must be tested on two contrary conditions"; a drug may act directly on a disease but also it may be effective against a different disease by relieving its symptoms.
4 "The quality of the drug must correspond to the strength of the disease...it is best to experiment first using the weakest [dosage] and then increase it gradually until you know the potency of the drug, leaving no room for doubt."
5 "One should consider the time needed for the drug to take effect. If the drug has an immediate effect, this shows that it has acted against the disease itself."
6 "The effect of the drug should be the same in all cases or, at least, in most. If that is not the case, the effect is then accidental, because things that occur naturally are always or mostly consistent."
7 "Experiments should be carried out on the human body [...] the quality of the medicine might mean that it would affect the human body differently from the animal body..."

Persian Father of Medicine, Avicenna (or Abu Ali Ibn Sina) and his Canon of Medicine (Arabic: القانون في الطب‎ al-Qānūn fī aṭ-Ṭibb) is an encyclopedia of medicine in five books compiled by Persian philosopher Avicenna (Ibn Sina) and completed in 1025. It presents an overview of the contemporary medical knowledge, which had been largely influenced by Galen.

The Canon of Medicine remained a medical authority for centuries. It set the standards for medicine in Medieval Europe and the Islamic world, and was used as a medical textbook through the XVIII century in Europe. It is still used in Unani medicine, a form of traditional medicine practiced in India.

Avicenna begins part one by dividing theoretical medicine and medical practice. He describes what he says are the "four causes" of illness, based on Aristotelian philosophy: The material cause, the efficient cause, the formal cause, and the final cause.

Material Cause Avicenna says that this cause is the human subject itself, the "members or the breath" or "the humours" indirectly.
Efficient Cause The efficient cause is broken up into two categories: The first is "Extrinsic", or the sources external to the human body such as air or the region we live in. The second efficient cause is the "Intrinsic", or the internal sources such as our sleep and "its opposite-the waking state", the "different periods of life", habits, and race.
Formal Cause The formal cause is what Avicenna called "the constitutions ; the compositions". According to Oskar Cameron Gruner, who provides a treatise within Avicenna's Canon of Medicine, this was in agreement with Galen who believed that the formal cause of illness is based upon the individual's temperament.
Final Cause The final cause is given as "the actions or functions".

In the thesis on General Physiology or "The Faculties of the Body", Avicenna separates life into three different categories: Vegetable, Animal, and Human. He contrasts Galen's view that the brain is the "chief seat of sentient life" with Aristotle's view that the heart is the source of all the body's faculties, saying that if physicians considered the matter carefully they would agree with Aristotle that the heart was the ultimate source of all the faculties, even if (for example) the brain is where the rational faculty manifests itself.

Book 5 (the Formulary) lists 650 compound drugs,[2][7]:23-24 attributing them to various Arabic, Indian and Greek sources. Avicenna added his own comments, highlighting differences between recipes from different sources, and sometimes giving his own recipe. He also gave his opinion of the effectiveness (or ineffectiveness) of some remedies, and gave details of where particular ingredients came from and how they were prepared. He favoured proven remedies which had been tested through experience, cautioning that compounds could have unexpected or much stronger effects than might be expected from the effects of the individual components.

Persian Father of Medicine, Avicenna (or Abu Ali Ibn Sina) and his Canon of Medicine (Arabic: القانون في الطب‎ al-Qānūn fī aṭ-Ṭibb) is an encyclopedia of medicine in five books compiled by Persian philosopher Avicenna (Ibn Sina) and completed in 1025. It presents an overview of the contemporary medical knowledge, which had been largely influenced by Galen.

The Canon of Medicine remained a medical authority for centuries. It set the standards for medicine in Medieval Europe and the Islamic world, and was used as a medical textbook through the XVIII century in Europe. It is still used in Unani medicine, a form of traditional medicine practiced in India.

Avicenna begins part one by dividing theoretical medicine and medical practice. He describes what he says are the "four causes" of illness, based on Aristotelian philosophy: The material cause, the efficient cause, the formal cause, and the final cause.

Material Cause Avicenna says that this cause is the human subject itself, the "members or the breath" or "the humours" indirectly.
Efficient Cause The efficient cause is broken up into two categories: The first is "Extrinsic", or the sources external to the human body such as air or the region we live in. The second efficient cause is the "Intrinsic", or the internal sources such as our sleep and "its opposite-the waking state", the "different periods of life", habits, and race.
Formal Cause The formal cause is what Avicenna called "the constitutions ; the compositions". According to Oskar Cameron Gruner, who provides a treatise within Avicenna's Canon of Medicine, this was in agreement with Galen who believed that the formal cause of illness is based upon the individual's temperament.
Final Cause The final cause is given as "the actions or functions".

In the thesis on General Physiology or "The Faculties of the Body", Avicenna separates life into three different categories: Vegetable, Animal, and Human. He contrasts Galen's view that the brain is the "chief seat of sentient life" with Aristotle's view that the heart is the source of all the body's faculties, saying that if physicians considered the matter carefully they would agree with Aristotle that the heart was the ultimate source of all the faculties, even if (for example) the brain is where the rational faculty manifests itself.

Book 5 (the Formulary) lists 650 compound drugs, attributing them to various Arabic, Indian and Greek sources. Avicenna added his own comments, highlighting differences between recipes from different sources, and sometimes giving his own recipe. He also gave his opinion of the effectiveness (or ineffectiveness) of some remedies, and gave details of where particular ingredients came from and how they were prepared. He favoured proven remedies which had been tested through experience, cautioning that compounds could have unexpected or much stronger effects than might be expected from the effects of the individual components.

A reflex is defined as a physiological reaction in a closed, mechanic stimulus-response system called a reflex arc. The reaction is automatic and does not involve the cerebrum. The word reflex is often used to describe reactions which do not fit the strict definition of a reflex, usually because they are immediate and unintentional. However, these characteristics are not enough to define a reaction as a reflex.
In this essay, Moshe Menasheof defines instinct, a reaction which, like reflex, can be immediate and involuntary, but unlike it is processed in the cerebrum. That is, an instinct is a reaction which originates in awareness. The instinctive reaction is only triggered when awareness identifies something to trigger it.
Another difference essential to the distinction between the two types of reactions is that reflexes do not change, while instincts do. The physiological mechanisms which activate instincts do not change, but the meanings that trigger them do, creating the appearance that instinctive reactions change during a person’s life.
Using these definitions and the distinction between reflex and instinct, the author gives the readers tools to help them in analyzing different reactions and deciding whether an immediate, involuntary reaction is truly a reflex, or actually an instinct. The author points to a number of examples which are mistakenly called reflexes, such as the cold crying reflex, which is actually an instinctive response. The essay also gives examples of cases which can be both a reflex and an instinctive reaction, such as vomiting.

خلال هذا الفصل تم تناول المشروع التطبيقى و تحديد نشاطة و هو تصميم منشأ إدارى بالعاصمة الإدارية الجديدة ، ثم تم تصميمه من منظور البعد الرابع .
تم تحديد هيكل المتتابعة الفراغية خارج المبنى الإدارى ، ثم تم تصميم الفراغ الداخلى بناء على هيكل المتتابعة البصرية .
تم إستلهام خطوط التصميم المستخدمة فى المشروع التطبيقى من الطبيعة، و تم تطويع الخطوط لتتناسب مع الوظيفة .
تم عرض الفراغ المستخدم بمفهوم البعد الرابع من خلال المساقط الأفقية و الرأسية و المناظير التوضيحية .

ARTÍCULOS

1) El vientre de los modernos. Psicología, fisiología y filología de la conciencia histórica
Filippo Fimiani
Università de Salerno
Universitè París I-Panthéon-Sorbonne

Traducido del francés por Yanina Benítez Ocampo y Santiago Bellocq
(Universidad Nacional de San Martín)

Resumen
“La ‘modernidad’ a través de la imagen de la comida y la digestión”. Ésta es la tarea y el programa de la genealogía fisiológica y psicológica identificada con claridad por Nietzsche en un fragmento del otoño de 1888 y firmemente perseguida en toda su obra. El diagnóstico es implacable y es posible por un uso extendido de la metáfora gastronómica, aplicada a todos los campos de la experiencia y el lenguaje por una escritura temeraria de la historia. Como Valéry y Péguy también lo ilustran, la experiencia de los hombres contemporáneos es pobre y enferma y se caracteriza por una duplicidad radical y una contradicción sin síntesis. No sólo las cosas, como además lo muestra en sus análisis sobre las mercancías como nuevos jeroglíficos que marcan el espacio saturado de la metrópolis, sino también el hombre es doble, así como su corporizada y profundamente fisiológica economía. Su estómago hambriento tiene dos caras, porque todo lo toma pero no nutre en absoluto; vocifera acerca de entusiasmos varios y heterogéneos, no sobre un verdadero alimento para ser absorbido y transformado. En resumen, vive por un instante sin pasado ni futuro. El opuesto de esta lógica de la enfermedad y la insensibilidad en busca de muchas sensaciones y shocks sensacionales, y el reverso de este olvido por rapidez excesiva, es un ser anti- o incluso premoderno en extremo. En los tiempos modernos, el entrenamiento de un criticismo genuino acerca de los prejuicios y el supuesto auto-conocimiento implican una regresión y una alteración de las propias identidades históricas, las creencias y los valores. Finalmente, como Benjamin y Warburg lo revelaron, el criticismo es como tornarse otra vez animal y la interpretación es como recuperar la lentitud y la melancolía de un eterno masticar, al igual que un perro o una vaca.

2)Palabra e imagen en la modernidad temprana. Representaciones de la barbarie mediante ilustración, écfrasis y alegoría
Nicolás Kwiatkowski
Consejo Nacional de investigaciones Científicas y Técnicas
Universidad Nacional de San Martín

Resumen
El objetivo de este artículo es indagar en el papel de las transposiciones como dispositivos de producción de identidad y alteridad en la modernidad temprana. Se analizarán usos concretos de ilustraciones, écfrasein y alegorías, y las características de su producción y recepción. Se buscará discernir el modo en que, mediante la transposición, se produjeron representaciones de varios Otros que, a su turno, contribuyeron a generar diversas identidades en el contexto europeo.

NOTA CRÍTICA

Memoranda Estética. Un manuscrito desconocido de Guillermo De Torre (1924)
Carlos García
Hamburg, Alemania

Resumen
Guillermo de Torre (1900-1971) fue miembro prominente del Ultraísmo, movimiento de avanzada español con ramificaciones en la América hispana. Publicó luego una obra standard: Literaturas europeas de vanguardia (1925). Torre fue también cuñado de Jorge Luis Borges. La mala relación entre ambos es bien conocida, al menos entre los especialistas, porque casi no hay biografía de Borges que la silencie. En el documento reproducido a continuación encontramos una rara excepción, puesto que en este caso es Torre quien critica a Borges. Más interesante es, empero, la crisis de la cual este manuscrito da testimonio: la evolución personal de Torre es la materia de su texto, su auto-compromiso en aras de la aventura y en contra del orden.

In order to stay alive, the body has to breathe the air. We breathe in oxygen and we breathe out carbon dioxide. This process is known as 'respiration'. Breathing happens automatically. Every day the body breathes about 20000 times. By the time we reach 70 years old, that's about 600 million breaths. All of this breathing occurs because of the respiratory system, which includes the nose, throat, voice box, windpipe, and lungs.

In the context of the great philosophical synthesis of Francis Suárez, between XVI and XVII centuries, his commentary to De Anima manifest the originality of his thought, between continuity and innovation in front of the big issues that Aristotle’s work had left open. His reflection on the problems of knowledge will open the path to a modern way of thinking, not exempt of some critical aspects. As he recognizes the active role of sensitive powers and he analyzes their physiological dimension, he will reduce inner sensitivity to only one power. The characterization of this only inner sense requires an adequate distinction of it as regards both external sensitivity and intellectual power, and implies some localization in the brain. Surarez’s dialogue with the physiology of his time places him at the historical beginning of neuroscience.

Tight junctions seal the luminal border of epitelial cells and restrict the passage of substances across the paracellular route. The resistance offered by this path way is variable and depends on the number of strands, the length of the intercelular cleft, and the posible existence of compartmentalized flickering channels spanning the strands.

di Giacomo Oliva, originalmente pubblicato sulla rivista Cannabis #11, Nautilus Edizioni, Torino, giugno 2002. Nel clima di persecuzione totale della cannabis caratteristico della fine degli anni '30 il consumatore/trice è stato tradizionalmente dipinto in diversi contesti come un essere spiritato in preda dei suoi istinti più bassi, ai " vizi " , con frequenti riferimenti più o meno morbosi ad ipotetici scenari di laida lussuria, sessualità possessiva, generando un inmmaginario costituito da contesti di oblio orgiastico & consumo di cannabinoidi. Questo quadro assai poco credibile ci ha fatto crescere il DESIDERIO di indagare sui diversi aspetti che riguardano il consumo di cannabinoidi ed il sesso. Comportamento Sessuale Il comportamento sessuale è costituito da una serie di fenomeni di natura volontaria e involontaria riguardanti una sequenza di eventi fisiologici e comportamentali che coinvolgono aspetti ormonali, circolatori, secretori e psichico-comportamentali. Il comportamento sessuale è regolato fisiologicamente dal nostro sistema nervoso centrale attraverso una serie di equilibri che riguardano diversi neuromendiatori: per primi analizziamo serotonina e dopamina. Queste due molecole biologiche prodotte all'interno dei nostri neuroni sono le responsabili dell'innesco dei vari meccanismi che regolano il comportamento sessuale. Questo tipo di comportamento è attivato da una diminuzione dell'attività della serotonina ed ad un aumento dell'attività della dopamina. L'area del cervello associata al comportamento sessuale è il sistema limbico sul quale si trovano ben distribuiti anche i recettori per i cannabinoidi. Il corredo ormonale è costituito una serie di biomolecole distinte genericamente in base al sesso in ormoni androgeni (maschili) e estrogeni (femminili) la cui funzione principale in entrambi i sessi è mediare tutti gli eventi fisiologici che portano alla produzione e maturazione di spermatozoi nell'uomo e dell'ovulo nella donna, agendo direttamente sui tessuti delle ghiandole genitali. L'attivazione del comportamento sessuale può partire da stimoli visivi, uditivi, olfattivi, gustativi, tattili o immaginativi, che andando ad eccitare i centri " erotici " del cervello (il sistema limbico, una struttura cerebrale coinvolta in tutti i fenomeni emotivo-affettivi e la ghiandola pituitaria la cui azione promuove la sintesi ed il rilascio di diversi ormoni). Questi stimoli scatenano una serie di impulsi che si diffondono attraverso la colonna vertebrale fino alle vertebre sacrale e toraco-lombare, da qui dipartono fibre che innervano l'apparato genitale causando l'erezione nell'uomo e un aumento del turgore e della secrezione delle mucose vaginali nella donna. E' ormai un dato di fatto che questi fenomeni sono mediati psicogenicamente dalla serie di stimoli prima elencata e riflessogenicamente nel caso della stimolazione diretta dei genitali. Nello studio del comportamento sessuale bisogna tristemente evidenziare una netta sproporzione numerica tra gli studi dedicati ai problemi dell'erettilità maschile rispetto a quelli dedicati ai meccanismi di attivazione sessuale del corpo femminile. L'erezione Riassumendo brevemente il fenomeno dell'erezione è così descritto: all'arrivo dello stimolo le arterie pudendali destra e sinistra iniziano a pompare sangue nei corpi cavernosi (due cavità simmetriche all'interno del pene maschile) e nel tessuto spugnoso (una struttura vascolare altamente ramificata), dai corpi cavernosi il sangue è selettivamente pompato nelle zone in cui il tessuto vascolare è più flaccido, andando a generare un turgore progressivo di tutto l'organo; una successiva contrazione di questi vasi impedisce il deflusso del sangue. L'ultima fase è l'eiaculazione che può essere schematizzata in tre momenti: 1) contrazione della muscolatura liscia ghiandole genitali per portare il seme nell'uretra (il condotto che porta all'esterno urina e spermatozoi) questo processo è detto EMISSIONE 2) contrazione dello sfintere uretrale: serve ad impedire il reflusso dello sperma nei testicoli

Pancreatic ductal adenocarcinoma (PDAC) is a highly aggressive malignancy with a dismal survival rate. Persistent activation of pancreatic stellate cells (PSCs) can perturb the biomechanical homoeostasis of the tumour microenvironment to favour cancer cell invasion. Here we report that ATRA, an active metabolite of vitamin A, restores mechanical quiescence in PSCs via a mechanism involving a retinoic acid receptor beta (RAR-b)-dependent downregulation of actomyosin (MLC-2) contractility. We show that ATRA reduces the ability of PSCs to generate high traction forces and adapt to extracellular mechanical cues (mechanosensing), as well as suppresses force-mediated extracellular matrix remodelling to inhibit local cancer cell invasion in 3D organotypic models. Our findings implicate a RAR-b/MLC-2 pathway in peritumoural stromal remodelling and mechanosensory-driven activation of PSCs, and further suggest that mechanical reprogramming of PSCs with retinoic acid derivatives might be a viable alternative to stromal ablation strategies for the treatment of PDAC.

Se analiza la relación de la teleología platónica y la fisiología médica de Alcmeón de Crotona y del  papel hígado en  el Timeo de Platón, su  función  en  el  cuerpo  y  su  relación con el alma apetitiva. A continuación, se explora la relación del hígado y el alma apetitiva  con el hombre tirano y la tiranía tal y como son caracterizados  en  la  República,  el  Timeo  y  las  Leyes, y la correspondencia entre fisiología, psicología  y  política.

Affective and cognitive factors play an important role in the activation and regulation of men’s sexual arousal. Barlow (1986) argued that initial affective reactions determine the allocation of attention to sexual stimuli. We applied Barlow’s model to our understanding of the role of sexual arousal in sexual orientation, where sexual arousal patterns have consistently been found to be congruent with self-reported orientation in men, but not in women. Visual attention of 28 heterosexual and 22 homosexual men to same- and opposite-sex erotic stimuli was assessed and experimentally-directed by means of a newly developed software application, while genital (penile rigidity) and affective responses (self-reported and physiological) were measured. In line with previous research, we found “category specificity” in men’s sexual arousal, in that sexual responses were strongest to orientation-congruent stimuli. Also, both homosexual and heterosexual men experienced stronger sexual responses to conditions in which their attention was directed to sexual versus nonsexual content of orientation-congruent stimuli. Only homosexual men manifested higher sexual responses when their visual attention was directed towards the sexual content of orientation-incongruent stimuli. Heterosexual men experienced weaker positive and stronger negative affective responses to orientation-incongruent content, suggestive of potential avoidance or inhibitory mechanisms.

This study investigates the effects of essential oil of Pterodon polygalaeflorus (EOPP) and β-caryophyllene (β-CAR). EOPP and β-CAR relaxed the basal tone of ileum smooth muscle in a concentration-dependent manner (IC50s = 394.35 ± 62.12 and 68.65 ± 9.51 μg/mL respectively), an effect that was unaltered by hexamethonium, L-nitroarginine methyl ester or indomethacin. Both EOPP and β-CAR evoked a concentration-dependent relaxation of ileum pre-contracted with KCl with an IC50 value of 107.78 ± 10.47 and 17.35 ± 0.75 μg/mL, respectively. EOPP and β-CAR inhibited the contractions induced by acetylcholine (ACh) and by KCl. In ileal preparations, the CaCl2-induced contractions were reduced by EOPP (300 μg/mL) and β-CAR (100 μg/mL). Furthermore, CaCl2-induced contractions were also reduced by EOPP (300 μg/mL) and β-CAR (100 μg/mL) in ileal preparations pretreated with ACh under Ca2+-free condition and in the presence of verapamil. EOPP (100 and 300 μg/mL) and β-CAR (30 and 100 μg/mL) reduced the ACh-induced contractions of isolated rat ileum under Ca2+-free conditions. In the presence of high KCl and Ca2+-free conditions, EOPP (300 μg/mL) and β-CAR (100 μg/mL) reduced the contractions induced by barium. A similar effect was also observed with verapamil. It is concluded that (i) β-CAR is an important constituent involved in the myorelaxant and antispasmodic effects induced by EOPP; (ii) the inhibitory effect on intestinal contractility is myogenic and seems mainly mediated through an intracellular mechanism. However, the ability of EOPP and β-CAR to decrease Ca2+ influx through cytoplasmic membrane could not be discounted.

Claudins are integral proteins of the TJ. Each epithelia in the organism expresses a unique set of claudins that determines the degree of sealing of the paracellular pathway and the ionic selectivity of the tissue. TJs are dynamic structures whose organization and composition change in response to alterations in the environment as well as under physiological and pathological conditions. Changes in claudin expression and subcellular distribution can be analyzed in western blot and immunofluorescence experiments, employing a wide array of available specific antibodies against claudins. In this chapter, we describe in detail protocols used for western blot and immunofluorescence detection of claudins in epithelial cell lines and in various tissue samples. Tight junctions (TJs) in epithelial cells localize at the most apical segment of the lateral membrane. TJ are integrated by a complex array of integral and peripheral proteins, among which claudins play a crucial role as back bone constituents of the filaments observed by freeze-fracture electron microscopy. The filaments that encircle epithelial cells below the apical microvilli are formed by lines of transmembrane particles with a 10 nm diameter that fuse when fixed with glutaraldehyde (1, 2). These particles are composed of claudin multimers, and their formation can be triggered upon claudin transfection, even in cells that lack TJs such as fibroblasts (3).

The making and sealing of a tight junction (T J) requires cell-cell contacts and Ca 2= , and can be gauged through the development oftransepithelial electrical resistance (TER) and the accumulation of ZO-I peptide at the cell borders. We observe that pertussis toxin increases TER, while AIF 3 and carbamil choline (carbachol) inhibit it, and 5-guanylylimidodiphosphate (GTPFs) blocks the development of a cell border pattern of ZO-I, suggesting that G-proteins are involved. Phospholipase C (PLC) and protein kinase C (PKC) probably participate in these processes since (i) activation of PLC by thyrotropin-1 releasing hormone increases TER, and its inhibition by neomycin blocks the development of this resistance; (ii) 1,2-dioctanoylglycerol, an activator of PKC, stimulates TER development, while polymyxin B and l-(5-isoquinoline sulfonyl)-2-methyl-piperazine dihydrochloride (H7), which inhibit this enzyme, abolish TER. Addition of 3-isobutyl-l-methyl-xanthine, dB-cAMP or forskolin do not enhance the value of TER, but have just the opposite effect. Triflu-operazine and catmidazoline inhibit TER development, suggesting that calmodulin (CAM) also plays a role in junction formation. These results indicate that junction formation may be controlled by a network of reactions where G-proteins, phospho-lipase C, adenylate cyclase, protein kinase C and CaM are involved .