By H. Ugolf. Mt. Sierra College.
For example buy 40 mg accutane free shipping, Zhou et al (1996) investigated the effect of acupuncture on blood pressure in rats with spontaneous hypertension 10mg accutane mastercard. Moreover, acupuncture along the heart meridian significantly increased the atrial natriuretic peptide and decreased the serum insulin and C-peptide, with an increased ratio of C-peptide/insulin. Thus, the mechanisms of anti-hypertension effect of acupuncture might involve the improvement of insulin resistance and increase in the atrial natriuretic peptide. Their results showed that when norepinephrine 2+ 2+ increased the blood pressure, [Ca ]i significantly increased, while [Mg ]i 2+ 2+ decreased with an increased ratio of [Ca ]i/[Mg ]i. Thus, they suggested that acupuncture could decrease the blood pressure, partially by regulating the cardiac function through the modulation of cytosolic-free calcium. However, more studies are needed to verify these observations and elucidate the precise meaning of this phenomenon. There has been evidence showing that an increase in the renal perfusion pressure could increase the expulsion of sodium and water. This could lead to hypovolemia and restore the arterial pressure to the control level. In addition, changes in the sympathetic nerve activity and vasoactive substances can alter natriuresis. A sympathetic hyperactive and vasoactive substance release can alter natriuresis and induce high blood pressure. The potential mechanisms of acupuncture therapy for hypertension are briefly summarized in Fig. The beneficial effect is relatively acupoint-specific and sensitive to the stimulation parameters (Song et al. This effect was observed only when the blood pressure was lower than the “normal” level, and acupuncture had no effect on the normal blood pressure in the control rats. However, when it reached a certain level, the blood pressure did not increase further with the intensity. In 20 healthy adult rabbits under urethane anesthesia, a decrease in the blood pressure was induced by cutting the bilateral vagus nerves and aortic nerves. The pressor effect was increased with the current intensity within a certain range. However, an intensity beyond that range could not increase the blood pressure further. Apparently, acupuncture-induced anti-hypotension depends upon appropriate stimulation intensity, besides specific acupoints (e. In a rat model of hypotension induced by vagus nerve stimulation, Deng and Huang (1981) investigated the relationship between the trigeminal nerve and Renzhong acupoint. Thus, it is evident that the nerve-based signals are critical in acupuncture-induced pressor. Indeed, endogenous opioid system has been observed to actively inhibit the sympathetic tone and negatively regulate the cardiovascular activity. For example, electrical stimulation of the hypothalamic defense area enhanced the sympathetic activity (Xia et al. In response to such stress, enkephalin was greatly increased in the cerebrospinal fluid (Xia et al. Indeed, some stressful conditions may lead to over-release of the opioids that contribute to hypotension. During trauma and hemorrhage, blockage of the opioid peptide activity might raise the blood pressure (Sun et al. Xia (1989) observed that severe trauma could seriously decrease the blood pressure, while i. Sun et al (1983) observed that in a rat model of hemorrhagic hypotension by vein bloodletting, simulated acupuncture (i. In the rat anesthetized by intraperitoneal injection of chloral hydrate, sciatic nerve stimulation still increased the blood pressure. However, sciatic nerve stimulation induced little or no increase in the blood pressure in most animals after i. Therefore, the authors believed that the sciatic nerve stimulation could strengthen the sympathetic excitement, and thus increase the blood pressure through cholinergic neurotransmitter system, but not the endogenous opioid system. Song et al (1990b) studied the effect of acupuncture on angiotensin Ċ in 20 rabbits with hemorrhagic shock by femoral artery bloodletting. However, 30 min after the shock, the level of plasma angiotensin Ċ significantly increased to 64. The level was even higher at 60 min after the shock, but was significantly lower in the acupuncture group. This may be beneficial in the early period of shock for recovering blood volume and redistributing the blood to important organs like the brain, heart, and kidney. In the non-acupuncture group, the angiotensin Ċ level was high, while the blood pressure decreased.
Nodules and pedunculated tumours are present in the congenital condition called neurofibromatosis (Von Recklinghausen’s disease) cheap 40mg accutane amex. The edge of lesions can give some diagnostic help: well-defined edges are espe- cially characteristic of psoriasis and ringworm cheap 10mg accutane visa. Characteristically, it is difficult to discern where the abnormality ends in the eczematous disorders. Some skin disorders start off as macular but clear in the centre, making ring-like or annular lesions. Ringworm, granuloma annulare (see page 265) and erythema multiforme (see page 75) are 16 Oedema, fluid-filled cavities and ulcers Figure 2. The individual papules have a roughly polygonal outline and are mauvish in colour. Some skin disorders often produce oval lesions, pityriasis rosea being the best example of this tendency. Occasionally, lesions assume bizarre patterns on the skin surface that almost seem to be representing a particular pattern or symbol. This is termed figurate, and many disorders, including psoriasis, may produce such lesions. For the most part, skin lesions are not usually angular and do not form squares or triangles. However, one condition, lichen planus (see page 144), does produce small lesions that seem to have a roughly polygonal outline (Fig. In some instances, lesions such as plaques or tumours infiltrate into the sub- stance of the skin and, in the case of such malignant lesions as basal cell carcin- oma, squamous cell carcinoma or malignant melanoma, it is important to recognize the presence of deep extensions of the lesion in order to plan treatment. Clinically, it is possible for experienced observers to form some impression of the degree of infiltration present by palpation, but this should be validated by histo- logical support before any major surgical decision is made. There is some hope that non-invasive assessment techniques such as ultrasound will be better able to guide the surgeon than clinical examination alone. Oedema, fluid-filled cavities and ulcers When a tissue contains excess water both within and between its constituent cells, it is said to be affected by oedema. Oedema fluid may collect because of inflam- mation, when it is protein rich and known as an exudate, or as a result of haemo- dynamic abnormalities, when it is known as a transudate. Oedema is a common feature of inflammatory skin disorders, being seen in acute allergic contact derma- titis. Oedema also occurs in urticaria and dermographism (see page 71) in which localized areas of pink, swollen skin (known as weals) occur, lasting for several hours (Fig. In eczema, oedema fluid collects within tiny cavities less than 1 mm in diameter within the epidermis, known as vesicles (Fig. These may form due to fluid collecting beneath the epider- mis (subepidermal), in which case their walls tend to be tough and the captured blister fluid may be blood stained, or they may form by separation or breakdown of epidermal cells (intraepidermal), when the walls tend to be thin, flaccid and fragile. Subepidermal bullae form in bullous pemphigoid, dermatitis herpetiformis and erythema multiforme. Intraepidermal bullae form in the different types of pemphigus (see page 91) and herpes virus infections (see Figs 2. Erosions may be covered by serous exudates or crust; ulcers tend not to be covered. Secondary changes Secondary changes include: ● impetiginization – due to a bacterial infection resulting in exudation and golden-yellow crusting (Fig. It is extremely itchy, and he scratches it vigorously, causing scratch marks or excoriations to appear. In some areas where he scratches and rubs persistently, the skin has become thickened and hypertrophied, with exaggeration of the skin surface markings – a change known as lichenification. In areas that are eczema free, there is xeroderma or drying of the skin with some fine scaling. In places where the eczema is active, the skin is red from the increased blood supply and swollen because of the oedema. Symptoms of skin disorder Skin disease causes pruritus (itching), pain, soreness and discomfort, difficulty with movements of the hands and fingers, and cosmetic disability. Any skin abnormality can give rise to irritation, but some, such as scabies, seem particularly able to cause severe pruritus. Most scabies patients complain that their symptom of itch is much worse at night when they get warm, but this is probably not specific to this disorder. Itching in atopic der- matitis, senile pruritus and senile xerosis is made worse by repeated bathing and vigorous towelling afterwards, as well as by central heating and air conditioning with low relative humidity. If pruritus is made worse by aspirin or food additives such as tartrazine, sodium benzoate or the cinnamates, it is quite likely that 20 Symptoms of skin disorder urticaria is to blame. Persistent severe pruritus can be the most disabling and dis- tressing symptom, which is quite difficult to relieve. Scratching provides partial and transient relief from the symptom and it is fruitless to request that the patient stop scratching.