By H. Grobock. Methodist College. 2018.
However generic 100 mg extra super cialis otc what causes erectile dysfunction treatment, the endogenous neurokinins approximately 50% of ascending dorsal raphe neurons in exhibit a high degree of cross-reactivity with these tachy- the primate brain (22 discount extra super cialis 100 mg on line erectile dysfunction treatment home,23). These findings provide further illustra- tions of the marked species differences in the neuroanatomy, SPECIES DIFFERENCES IN THE and possibly physiology, of neurokinin systems. The func- DISTRIBUTION OF NEUROKININS AND tional significance of substance P and 5-HT coexpression THEIR RECEPTORS IN THE NERVOUS in the human brain is not known, but it suggests that both SYSTEM neurotransmitters may be coreleased in certain brain regions receiving terminal innervation. The substance P–preferring NK1 receptor has attracted Other evidence suggests that substance P and NKB may most interest as a CNS drug target because it is the predomi- also modulate ascending norepinephrine systems. NK1 re- nant tachykinin receptor expressed in the human brain, ceptors (25) have been shown to be expressed on tyrosine whereas NK2 and NK3 receptor expression is extremely low hydroxylase–positive cell bodies in the rat locus ceruleus, or absent (10–12). Therefore, it appears that the central and both substance P and senktide (a selective NK3 receptor actions of all tachykinins may be mediated predominantly agonist) excite the firing of locus ceruleus neurons in rats through the NK1 receptor in humans. For example, in the rat and TACHYKININ RECEPTOR PHARMACOLOGY guinea pig brain, both NK1 and NK3 receptors are expressed (10), findings suggesting that the CNS functions mediated Preclinical studies with NK1 receptor antagonists have also by NK1 receptors in the human brain may be subserved by been complicated by species variants in NK1 receptor phar- NK1 and/or NK3 receptors in rodents. Compounds such as CP-96,345 were pear to be absent in the adult mammalian brain of all species found have high (nM) affinity for the NK1 receptor ex- examined (10). For these reasons, interpretation of the ef- pressed in human, gerbil, rabbit, guinea pig, cat, and mon- fects of selective tachykinin receptor antagonists in preclini- key brain, but they had considerably lower affinity for the cal assays requires great caution. If such compounds either mouse and rat NK1 receptor. Subsequent mutation analysis succeed or fail to exhibit activity in rodent assays for psychi- revealed that subtle differences in the amino acid sequence atric and neurologic disorders, this may merely reflect differ- between the human and the rat NK1 receptor dramatically ent roles of tachykinin receptors in rodent versus human alter antagonist binding affinity (30). Hence there is a risk of both false-positive and false- greatly hindered preclinical evaluation of high-affinity negative extrapolations from preclinical species to humans. Based on these neuroanatomic and functional PHARMACOLOGY IC FOR INHIBITION OF [125I]SP 50 studies, it was anticipated that NK1, and possibly NK2, BINDING (nM) receptor antagonists could be developed as analgesic drugs. Compound Human Gerbil Guinea Pig Rat Electrophysiologic studies on anesthetized or decerebrate animals provide evidence of potent and selective inhibition L-733060 0. Responses of dorsal horn neurons to noxious SR140333 0. NK1 receptor antago- nists have also been shown to inhibit the late-phase response commonly used preclinical species (Table 13. A few com- to formalin in gerbils (42), to inhibit carrageenan and pounds have high affinity for the rat receptor (e. SR140333), but their utility for in vivo studies may be se- Webb, S. Rupniak, unpublished observa- verely limited by poor brain penetration (31). Although tions; 43), and to attenuate peripheral neuropathy in rats these difficulties may be overcome by administering high and guinea pigs (43,44). Overall, the profile of activity of doses of NK1 receptor antagonists to rats, unspecific phar- NK1 receptor antagonists in a range of assays is comparable macologic effects are then frequently encountered, mostly to that seen with clinically used analgesic agents such as attributable to ion channel blockade. Pharmacologic differences among human, guinea cacy of these compounds in humans and are reviewed in pig, and rat NK3 receptors also exist (32). The patient populations and com- pounds examined included the following: peripheral neu- ropathy, in which CP-99,994 had no analgesic effect (47); POTENTIAL FOR USE OF TACHYKININ molar extraction, in which MK-869 was ineffective (48); RECEPTOR ANTAGONISTS TO TREAT and postherpetic neuralgia, in which MK-869 was ineffec- PSYCHIATRIC AND NEUROLOGIC tive (49). Further unpublished studies with other com- DISORDERS pounds support these conclusions. Thus, clinical studies to date indicate that NK1 receptor antagonists do not have The distribution of neurokinins in the central and periph- major potential as analgesics. The major hypotheses that are supported 10207 completely blocked both facilitation and protective by preclinical data and have been investigated in clinical nociceptive reflex responses (40), and SR48968 reduced re- trials are considered here. Numerous clinical trials have now sponses to both noxious and innocuous pressure applied to been conducted with NK1 receptor antagonists to define their therapeutic potential in psychiatric and neurologic dis- orders. In all these studies, the compounds have been ex- tremely well tolerated, with no significant side effects. PRECLINICAL EVIDENCE OF AN ANALGESIC PROFILE OF NK1 RECEPTOR are as yet no reports of clinical trials with NK2 or NK3 ANTAGONISTS receptor antagonists in patients with CNS disorders. Assay Morphine Indomethacin NK1 Antagonist Tail flick/hot plate √ Pain Paw pressure √ Writhing Radioligand-binding studies confirm the expression of Formalin paw tachykinin NK1 and NK3 (but not NK2) receptors in the Carrageenan paw dorsal horn of the spinal cord (33–35). A role of spinal Nerve injury √ X √ CFA arthritis substance P and NKA in nociception is suggested by the Facilitated spinal reduction in response thresholds to noxious stimuli by cen- reflex tral administration of NK1 and NK2 (but not NK3) agonists 172 Neuropsychopharmacology: The Fifth Generation of Progress the knee joint (50).
They travel longitudinally through a physical medium determining high pressure areas (compression) and low pressure areas (rarefac- tion) along the direction of propagation 100mg extra super cialis visa impotence viriesiem. Each wave has a fre- quency (f) of propagation measured as cycles per unit of time buy extra super cialis 100mg amex impotence 16 year old. The wavelength (λ) is defined as the geometric distance at an in- stant between two successive high pressure pulses or two successive low pressure pulses. The wavelength of sound decreases as frequency increases. Ultrasound and Regional Anesthesia | 25 the wave (c) depends on the physical properties of the medium (Figure 2. Ultrasounds are cyclic sound pressures with a frequency above those which humans can hear. Ultrasounds used in the medical setting have a frequency of 1 to 25 mHz. Sound waves are not ionising and are not harmful at the energy levels used for diagnostic purposes. There is to date no epidemiological evidence of harmful effects (Moore 2011). Ultrasounds travel faster in dense bodies and slower in compressible bodies. In soft tissue the speed of sound is 1540 m/s, in bone about 3400 m/s, and in air 330 m/s. In tissues where the sound travels more slowly, the wavelength decreases. Medical ultrasound waves are produced by a piezoelectric crystal as a consequence of the mechanical response to an electric field. The transducer also picks up the reflected waves or “echoes” from the tissues and converts them into electrical signals that are used to form real-time images on a computer. The crystal thus both transmits and receives the sound (Figure 2. From top to bottom: linear 10 and 18 and convex 5 mHz transducers. Each electric signal is registered, amplified, and filtered to reduce noise, and the depth of the tissue that has generated the echo is calculated. The signals are then digitalized and processed in order to produce an image. Ultrasound and Regional Anesthesia | 27 Early ultrasound devices used a single crystal to create a one dimension image, called a-mode image. Modern machines generate a b-mode or two-dimensional or gray-scale image created by 128 or more crystals. Each crystal receives a pulse that produces a scan line used to create an image on the screen. This image is renewed several times each second to produce a real-time image. Additional modes, including high resolution real time gray scale imaging, Doppler mode, color-flow Doppler mode, color-velocity Doppler and tissue harmonic modes are now commonly available. At the interface where one tissue borders another tissue, the wave is refracted and reflected back as an echo. The reflection depends on the tissue density and thus on the speed of the wave. So, as the waves penetrate tissues, they detect where soft tissue meets air, or soft tissue meets bone, or where bone meets air. Instead, some structures will completely absorb the sound waves. Thus, echoic tissues are those tissues that reflect the wave whereas anechoic tissues do not reflect the wave. Ultrasounds penetrate well through fluids that are anechoic and appear as black on the monitor.
In patients COMORBIDITY with abnormal risk assessment discount extra super cialis 100 mg visa natural erectile dysfunction treatment remedies, high levels of anxiety are associated with symptoms purchase extra super cialis 100 mg fast delivery impotence blood circulation. They are also likely to have com- We have become increasingly interested in developing a orbid axis I generalized anxiety disorder or social phobia, model for subtyping patients with OCDaccording to what avoidant and dependent personality features, and a family we see as the three core features of the disorder: abnormal history of an anxiety disorder. In contrast, patients with risk assessment, pathologic doubt, and incompleteness. These patients are also in a million chance that the elevator cable will snap, the more likely to exhibit incompleteness. In the same way, many of the thoughts of the 107 patients with OCDwho completed the Y-BOC Symp- patient with OCDare dominated by improbable events that tom Checklist and examined the correlations between the most of us would not think twice about. Many checkers factor scores and the presence of comorbid tic or personality suffer from 'what if? Three factors, symmetry/hoarding, contamina- Chapter 111: Obsessive-Compulsive Disorder 1605 tion/cleaning, and pure obsessions, best explained the vari- incomplete remission that permits normal social function- ance. Only the first factor was significantly related to OCPD ing. Although the results of studies varied considerably in (obsessive-compulsive personality disorder) or a lifetime his- regard to the percentage of patients in each category, the tory of Tourette syndrome. These figures are consistent COMMENT with our own study of patients meeting DSM-III criteria for OCD(Table 111. Although previous descriptive studies During the past 15 years, significant advances have revolu- found a chronic waxing and waning course in 85% of pa- tionized the way we conceptualize and treat OCD. Epide- tients, no attempt was made in previous studies to subdivide miologic studies have confirmed that OCDis an underrec- the waxing and waning course into predictable patterns or ognized common major psychiatric disorder with a lifetime subtypes. More recent studies in which a prospective design prevalence of 2% to 3% in the general population, and and standardized criteria were used have shown that the they have been instrumental in focusing the attention of episodic form of this disorder (clear periods of remission researchers, clinicians, and the media on OCD. Studies of while the patient is off medication) is uncommon. The peri- the clinical features and course of the disorder and associated odicity, duration, and severity of episodes in patients with comorbid conditions have appeared in the literature since OCDvary considerably. Once established, obsessions and the turn of the twentieth century and have been the subject compulsions usually persist, although the content, intensity, of numerous prospective and retrospective studies of its and frequency of the symptoms change over time. The introduction of the SSRIs has led to a significantly Finally, future studies will continue to benefit from fur- improved prognosis for patients with OCDduring the last ther refinement of our thinking about the heterogeneity decade. The identification of an OCD–tic subtype has tion, 64% had a decrease of more than 50% in Y-BOCS already led to important new genetic and biological studies score, and 33% had a decrease of more than 75% in Y- and has been directly relevant to treatment. These results are at odds with fort to characterize pediatric autoimmune neuropsychiatric those of two other prospective longitudinal observational disorders and their relationship to genetic vulnerability to studies of the course of OCDthat have recently been initi- streptococcal infection offers a promising lead for furthering ated at our site. It is compulsive outpatients evaluated at the Yale–Brown clinics possible that we will increase our understanding of predic- and followed them prospectively during a 2-year period. Of tions of remission and relapse related to possible homogene- the 51 patients who started the study meeting full criteria, ous subtypes of illness. A review of these studies suggests 57% still met full criteria after 2 years. Survival analysis that the course of OCD, long thought to be chronic, may revealed a 47% probability of achieving at least partial re- be more episodic than previously believed, particularly in mission during the 2-year study period. It also appears that in some sub- tive study, by Steketee et al. However, a long-term prospec- of partial remission for at least a 2-month period was 53%, tive follow-up study of a large number of patients with and for full remission (no longer meeting criteria) at 5 years OCDis needed to confirm these observations. Rasmussen receives research support from Solvay Phar- maceuticals and Pfizer. The prevailing notion that the course of OCDis chronic and deteriorating has not been consistently borne out by the evidence, particularly in children followed prospectively. REFERENCES Furthermore, the natural course of this disorder appears to have been altered by the availability of effective pharmaco- 1. Lifetime preva- lence of specific psychiatric disorders in three sites.
The fibrils are defined only on electron m icroscopy and have an appearance order extra super cialis 100 mg impotence means, at first glance extra super cialis 100mg amex impotence depression, sim ilar to am yloid. Patients with fibrillary glom erulonephritis usually exhibit protein- uria often in the nephrotic range, with variable hem aturia, hyper- tension, and renal insufficiency. A, O n light m icroscopy the glom eruli display widened m esangial regions, with variable increase in cellularity and thickened capillary walls and often with irregularly thickened basem ent m em branes, double contours, or both. B, O n im m unofluorescence, there is coarse linear or conflu- ent granular staining of capillary walls for im m unoglobulin G and com plem ent C3 and sim ilar staining in the m esangial regions. O ccasionally, m onoclonal im m unoglobulin G k deposits are identi- fied; in m ost instances, however, both light chains are equally rep- C resented. C, O n electron m icroscopy the fibrils are roughly 20-nm thick, of indefinite length, FIGURE 2-30 (see Color Plate) and haphazardly arranged. The fibrils perm eate the m esangial Light, im m unofluorescent, and electron m icroscopy in nonam yloid m atrix and basem ent m em branes (arrow). The fibrils have been fibrillary glom erulonephritis. Fibrillary glom erulonephritis is an infrequently described in organs other than the kidneys. Im m unotactoid glom erulopathy appears to be an im m une-m ediated glom erulonephritis. O n electron m icroscopy the deposits are com posed of m ultiple m icrotubular structures in subepithelial or subendothelial locations, or both, with lesser involvem ent of the m esangium. Patients with this disorder typically exhibit m assive proteinuria or nephrotic syndrom e. This glom eru- lopathy frequently is associated with lym phoplasm acytic disorders. A, O n light m icroscopy the glom erular capillary walls often are thickened and the m esangial regions widened, with increased cellu- larity. B, O n im m unofluorescence, granular capillary wall and m esangial im m unoglobulin G and com plem ent C3 deposits are pre- sent. The ultrastructural findings are of aggregates of m icrotubular structures in capillary wall locations corresponding to granular deposits by im m unofluorescence. C, The m icrotubular structures C are large, ranging from 30- to 50-nm thick, or m ore (arrows). The collagens norm ally found in glom erular basem ent m em - For reasons that are not clear, hem olytic-urem ic syndrom e has branes and the m esangial m atrix are of types IV (which is dom i- evolved in a sm all num ber of pediatric patients. In collagenofibrotic glom erulopathy, accum ulation m icroscopy the capillary walls are thickened and m esangial of type III collagen occurs largely in capillary walls in a suben- regions widened by pale staining m aterial. It is likely that this disease is hereditary; how- sharp contrast to the norm al staining of the capillary basem ent ever, because it is very rare, precise inform ation regarding trans- m em branes, as evidenced by the positive period acid–Schiff reac- m ission is not known. W ith this stain, collagen type III is not stained and there- nally was thought to be a variant of nail-patella syndrom e. Current evidence suggests little relationship exists between the B, O n electron m icroscopy, banded collagen fibrils are evident two disorders. Patients with collagen III glom erulopathy often in the subendothelial aspect of the capillary wall. Cam eron JS, Glassock RJ: The natural history and outcom e of the 4. Ponticelli C: Cyclosporine versus cyclophospham ide for patients with nephrotic syndrom e. Edited by Cam eron steroid-dependent and frequently relapsing idiopathic nephrotic syn- JS and Glassock RJ. Cam eron JS: The long-term outcom e of glom erular diseases. Ponticelli C, Glassock RJ: Treatm ent of Segm ental G lom erulonephritis. Classification and treatment of steroid-dependent nephrotic syndrome: comparison of an Atlas of G lom erular D isease, edn 2.
Te efcacy SSG/PM combination therapy for treatment of of the SSG/PM combination given for a shorter VL in East Africa 100mg extra super cialis amex erectile dysfunction gay. A WHO Expert Committee duration of 17 days was similar to the efcacy of recommended its use as a frst-line treatment for SSG given alone for 30 days (91 discount extra super cialis 100mg with mastercard erectile dysfunction age 60. Tere were no apparent diferences in the safety profle of Main conclusions the three treatment regimens. An observational multicountry study was con- ■ Te fndings supported the introduction of ducted in primary government health facilities SSG and PM combination therapy as a frst- in Bangladesh, Brazil, Uganda and the United line treatment for VL in East Africa. Te clinical perfor- mance of health workers with a longer duration of pre-service training (such as doctors and clin- Case-study 8 ical ofcers) was compared with those having a shorter duration of training (all other health Task shifting in the scale-up workers such as nurses, midwives and nurse of interventions to improve assistants providing clinical care). Te quality of care was evaluated using standardized indica- child survival: an observational tors and according to whether the assessment, multicountry study in Bangladesh, classifcation and management of sick children Brazil, Uganda and the United by IMCI guidelines had been fully carried out. Every child was assessed twice, frst by the IMCI- Republic of Tanzania trained health worker who was being assessed and second by a supervisor who was blinded to The need for research the original diagnosis and treatment made by WHO estimates that the global health workforce the health worker. Although this research has has a defcit of more than four million persons been classifed as a study of the management of (51). Countries with high child mortality rates diseases and conditions, it is also health policy also tend to have a lack of qualifed health work- and systems research. Te Integrated Management of Childhood Illness (IMCI) is a global strategy that has been Summary of fndings adopted by more than 100 countries with a view Te study included a total of 1262 children to reducing child mortality. IMCI clinical guide- from 265 government health facilities: 272 chil- lines describe how to assess, classify and manage dren from Bangladesh, 147 from Brazil, 231 children younger than fve years of age who have from the United Republic of Tanzania, and 612 common illnesses (52). In Brazil, 58% of health workers expanding IMCI coverage is the lack of qualifed with training of long duration provided cor- health workers. Task shifing, which is the term rect management, compared with 84% of those used to describe the process whereby specifc tasks with shorter duration of training. In Uganda are moved, where appropriate, to health workers the fgures were 23% and 33% respectively with fewer qualifcations and a shorter duration of (Table 3. Similarly, in Bangladesh and the pre-service training is seen as an option to address United Republic of Tanzania, the proportions of shortages of personnel (53). Assessment, classifcation and management of children by IMCI-trained health workers, classifed by length of pre-service training Longer duration of training Shorter duration of training Index of assessment of childrena Bangladesh 0. Adapted, by permission of the publisher,from Huicho et al. It should also be noted that these assessments pre-service training. Although all cadres of were made at the primary care level where fewer health workers apparently need additional children have serious illnesses (the proportion of training in some settings, task shifting has hospital referrals ranged from 1% in Brazil to 13% the potential to expand the capacity of IMCI in Uganda). Furthermore, health workers with a and other child survival interventions in shorter duration of training may be more willing underserved areas faced with staff shortages to comply with standard clinical guidelines (and (54–56). Randomized trials have also shown therefore be judged to have managed children that task shifting from doctors to other less correctly) whereas those with longer training qualified health workers is possible and can may use a wider variety of diferent procedures be beneficial where health service staff are in and yet obtain equally good outcomes. All nine peripheral health centre maternity units in the Case-study 9 district were linked to a central EMOC facility and an ambulance service via cell phones or high Improving access to emergency frequency radios. On receiving a woman with an obstetric care: an operational obstetric complication, health centre staf con- tacted the EMOC facility and an ambulance was research study in rural Burundi dispatched (accompanied by a trained midwife) to transfer the woman to the EMOC facility. Te The need for research distance from health centres to the EMOC facil- MDG 5 sets the target of reducing the maternal ity ranged from 1 km to 70 km. The MMR is an important measure by estimating how many deaths were averted of maternal health at the population level and is among women with a severe acute maternal defined as the number of maternal deaths in a morbidity (SAMM) who were transferred to and given time period per 100 000 live births during treated at the EMOC facility. Although maternal comparing the number of deaths among women mortality decreased in low- and middle-income with SAMM who were benefciaries of the EMOC countries from 440 deaths per 100 000 live intervention with the expected number of deaths births in 1990 to 290 per 100 000 in 2008, this among the same group of women assuming that 34% reduction is well short of the 75% target the EMOC intervention had not existed (63). The MMR conditions, including prolonged or obstructed in Burundi is among the highest in the world labour requiring a caesarean section or instru- at 800 per 100 000 live births (in comparison, mental (vacuum-assisted) delivery, complicated Sweden has a ratio of two per 100 000 live abortion (spontaneous or induced), pre-eclamp- births) (62). Using the estimate of care (EMOC) package is a widely accepted inter- averted deaths, the resulting theoretical MMR vention for reducing maternal deaths, no pub- in Kabezi was calculated and compared to the lished data exist from Africa that quantify the MDG 5 target for Burundi. Would the provision Summary of fndings of a centralized EMOC facility, coupled with an During 2011, 1385 women were transferred to the efective patient referral and transfer system for EMOC facility, of whom 765 (55%) had a SAMM obstetric complications, in a rural district sub- condition (Table 3.
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