By C. Kafa. East Carolina University.
As for the prior study purchase micardis 20 mg visa, this finding provides ductions in DA D2 receptor availability when compared evidence of a role for serotonin in alcoholism and in its with controls (67 buy micardis 20 mg amex,68) generic 20mg micardis with amex. No significant correlations were involvement with depressive symptoms during withdrawal. One of these studies also Opioid System measured DATs in a subgroup of the alcoholics in whom reductions in DA D2 receptors were detected and reported The effects of an oral naltrexone challenge on CBF in pa- no changes in DAT availability (68). This finding was inter- tients with alcoholism during detoxification was studied preted as evidence of GABAergic involvement in patients with SPECT and HMPAO. At baseline, patients with alco- with alcoholism because DA D2 receptors in striatum are holism showed lower CBF in left orbitofrontal cortex and mainly localized in GABA cells. After naltrexone, a signifi- DAT availability in patients with alcoholism has been cant regional CBF decrease was found in basal ganglia and measured by various PET and SPECT studies. The results the left mesial temporal region, which are structures rich in have not been consistent. These results were interpreted as support- reported that a group of violent patients with alcoholism ing the involvement of the opioid system in alcohol depen- had increases (8%) and nonviolent patients with alcoholism dence (76). SPECT studies in nonviolent patients with late-onset Spectroscopic Studies alcoholism have also reported a reduction in DATs (70). However, a PET study done with [11C]D-threo-MP and a Patients with alcoholism had a significant reduction of the SPECT study done with [123I] -CIT showed no changes cerebellar N-acetylaspartate–to-creatine ratio, which was in- in DATs in patients with alcoholism (71,68). These discrep- terpreted as reflecting neuronal loss and a reduction of the ancies are likely to reflect in differences in the time since choline-to-creatine ratio, which was interpreted as reflecting detoxification. One SPECT study showed that whereas cell membrane modification or myelin alterations (77). DAT levels were significantly reduced in patients with alco- holism within the first few days of last alcohol use, the levels Subjects at Risk of Alcoholism returned to normal 4 weeks after detoxification (72). PET studies with 6-[18F]-FDOPA (a marker for the DA synthesis The regional brain metabolic response to lorazepam was in the DA terminal) in patients late-onset (type 1) alcohol- evaluated in subjects with a positive family history of alco- ism showed higher striatal 6-[18F]-FDOPA uptake in the holism (FHP) and was compared with that of subjects with- patients with alcoholism than in the controls, a finding that out a family history of alcoholism (FHN) (78). At baseline, was interpreted as a compensatory mechanism to low post- FHP subjects showed lower cerebellar metabolism than synaptic DA function (73). FHN, and when challenged with lorazepam, they also showed a blunted response in cerebellum and in anterior cingulate gyrus. Lorazepam-induced changes in cerebellar Serotonin System metabolism were significantly correlated with motor impair- The effects of m-chlorophenylpiperazine (mCPP), a mixed ment. The blunted cerebellar sensitivity to benzodiazepines serotonin agonist-antagonist drug, on brain glucose metab- in FHP could account for the decreased sensitivity to the olism was compared in patients with alcoholism and in con- motor effects of alcohol and benzodiazepines in FHP sub- 1484 Neuropsychopharmacology: The Fifth Generation of Progress jects. The decreased cerebellar baseline metabolism in FHP in cerebral high-energy phosphates and in phospholipid me- subjects as well as the blunted cerebellar response to lora- tabolites. Marijuana Opiates Marijuana is the most widely used illicit drug of abuse in the United States. Despite its widespread use, the mecha- The effects of morphine on brain glucose metabolism were 9 nisms by which -tetrahydrocannabinol (THC) (the main evaluated in polydrug abusers (79). This study showed that psychoactive substance of marijuana) exerts its psychoactive morphine reduced glucose metabolism by 10% in whole effects are still not known. Relatively few imaging studies brain and by about 5% to 15% in telencephalic areas and have been done to assess the effects of acute and chronic the cerebellar cortex. Morphine-induced metabolic decre- marijuana use in the human brain. The effects of acute fentanyl, a synthetic opiate, on CBF were measured with PET and [15O]water. Fentanyl Brain Metabolism and Cerebral Blood Flow administration was associated with significant increases in regional CBF in cingulate, orbitofrontal, and medial pre- SPECT studies assessed the effect of THC intoxication on frontal cortices, as well as caudate nuclei, areas known to CBF in chronic marijuana users (84,85). Acute marijuana be involved in reward and addiction (80). In a more continuation and then retested 2 weeks later (81). The recent study, these investigators extended these findings to initial scans demonstrated significant CBF defects in the a larger groups of subjects and documented increases in frontal, parietal, and temporal cortices.
Although some significant correlations is involved in the pathophysiology of negative symptoms with symptoms clusters and regional benzodiazepine densi- and cognitive impairment in schizophrenia (14 cheap 40 mg micardis visa,16) order micardis 40 mg. Fur- ties have been observed (91 purchase 80 mg micardis otc,92,94,95), these relationships Chapter 59: Neurochemical and Neuropharmacological Imaging in Schizophrenia 841 have not been replicated by other studies. Thus, together, selective D2 receptor antagonists (haloperidol and raclo- these studies are consistent with an absence of marked ab- pride) suggested that 50% to 60% occupancy was required normalities of benzodiazepine receptor concentration in the to observe a rapid clinical response (107,108). Alterations of GA- pine, at clinically therapeutic doses, achieved only 40% to BAergic systems in schizophrenia might not involve benzo- 60% D2 receptor occupancy (104,106,109), which, in con- diazepine receptors (96), or be restricted to certain cortical junction with its anticholinergic properties, accounts for layers or classes of GABAergic cells that are beyond the its low liability for extrapyramidal symptoms (EPSs). Recent developments in GABA imaging with MRS antagonists' such as risperidone does not confer protection (described below) are a promising new avenue to study in against EPS, because the threshold of D2 receptor occu- vivo GABAergic function in schizophrenia. Given the relatively recent development tors might be sufficient to elicit clinical response (114,115). The concentra- 123 degree of occupancy achieved by atypical antipsychotic tion of SERT in the midbrain measured by [ I] -CIT is drugs in striatal and extrastriatal areas. Studies with reported lower occupancy of striatal D2 receptors compared more specific ligands are warranted to assess the distribution to temporal cortex D2 receptors in seven patients treated of SERT in other brain areas, such as the PFC, where their density has been reported to be reduced in three out of four with clozapine, using the high-affinity SPECT ligand [123I]epidipride. In contrast, typical antipsychotics were re- postmortem studies (97). Decrease in 5-HT2A receptors has been reported in the PFC in four out of eight postmortem ported to achieve similar occupancy in striatal and extras- triatal areas, as measured with [11C]FLB 457 (117) or studies (97,98). Three PET studies in drug-naive or drug- [123I]epidipride (118). It should be noted, however, that free patients with schizophrenia reported normal cortical 5-HT2A receptor binding (98–100), whereas one study re- these very high affinity ligands do not allow accurate deter- ported a significant decrease in PFC 5-HT2A binding in a mination of D2 receptor availability in the striatum. In con- trast, [18F]fallypride enables accurate determination of D2 small group (n 6) of drug-naive schizophrenic patients (101). The most consistent abnormality of 5-HT param- receptor availability in both striatal and extrastriatal areas eters reported in postmortem studies in schizophrenia is an (119), and preliminary PET experiments in primates with increase in the density of 5-HT receptors in the PFC, [18F]fallypride indicate that clozapine and risperidone 1A reported in seven out of eight studies (97). Several groups achieve similar D2 receptor occupancy in striatal and extra- are currently evaluating the binding of this receptor in vivo striatal regions (120). Finally, it is important to point out with PET and [11C]WAY100907. Improved resolution of PET cameras cur- Maybe the most widespread use of neuroreceptor imaging rently allows dissociating signals from ventral and dorsal in schizophrenia over the last decade has been the assessment striatum (123,124), and it is now feasible to specifically of neuroreceptor occupancy achieved by typical and atypical study the clinical correlates of D2 receptor occupancy in antipsychotic drugs, a topic that has been the subject of ventral striatum in humans. Neuroreceptor studied included Another unresolved question is the discrepant values of essentially D2 receptors, but also 5-HT2A and D1 receptors. The haloperidol plasma concentration as- sociated with 50% inhibition of [11C]NMSPbinding (3 to threshold of occupancy of striatal D2 receptors (about 80%) above which extrapyramidal side effects are likely to occur 5 mg/mL) (125) is ten times higher than that associated with 50% inhibition of [11C]raclopride binding (0. Quetiapine, at a dose of 750 mg, decreased [11C]raclopride-specific binding by 51%, but failed to affect sponse (105,106). Yet, most studies were performed at doses [11C]NMSP-specific binding (127). These observations achieving more than 50% occupancy, and the minimal level of occupancy required for therapeutic response remains un- contribute to the debate regarding differences between ben- defined. Two studies performed with low doses of relatively zamides and butyrophenones binding to D2 receptors. For example, despite major research ef- of the nucleus. An MRS experiment involves four steps, forts, direct measurement of parameters of glutamate trans- analogous to an MRI procedure. First, specific nuclei are mission are still not available. Radiotracers enabling evalua- excited with a brief 'pulse' of a radiofrequency (RF) mag- tion of second messengers and intracellular pathways are netic field supplied by an RF transmitter coil. A growing collaboration tion causes magnetized spins to transiently assume a higher between academic centers and industry currently holds the energy state, from which they 'relax' to a lower energy state promise of increasing access to molecules for evaluation as of equilibrium magnetization. Because the energy states are candidate radiotracers.
Crit Care M ed 1985 generic micardis 20 mg without a prescription, SAPS by selecting independent variables order 20mg micardis free shipping. Bion JF discount 20 mg micardis visa, Aitchison TC, Edlin SA, Ledingham IM : Sickness scoring and system: Risk prediction of hospital mortality for critically ill hospitalized response to treatm ent as predictors of outcom e from critical illness. Chew SL, Lins RL, Daelem ans R, De Broe M E: O utcom e in acute score for ICU patients. Liaño F: Severity of acute renal failure: The need of m easurem ent. Le Gall, Lem eshow S, Saulnier F: A new Sim plified Acute Phisiology N ephrol D ial Transplant 1994, 9(Suppl. Score (SAPS II) based on a European/N orth Am erican m ulticenter study. Bonom ini V, Stefoni S, Vangelista A: Long-term patient and renal prognosis in acute renal failure. Turney JH : W hy is m ortality persistently high in acute renal failure? Knaus W A, Draper EA, W agner DP, Zim m erm an JE: Prognosis in APACH E II en el fracaso renal agudo de las unidades de cuidados acute organ-system failure. Racusen cute renal failure (ARF) in the transplanted kidney represents a high-stakes area of nephrology and of transplantation practice. AA correct diagnosis can lead to rapid return of renal function; an incorrect diagnosis can lead to loss of the graft and severe sequelae for the patient. In transplant-related ARF percutaneous kidney allograft biopsy is crucial in differentiating such diverse entities as acute rejection (Figs. In the case of acute rejection, standardization of transplant biopsy interpretation and reporting is necessary to guide therapy and to estab- lish an objective endpoint for clinical trials of new immunosuppressive agents. The Banff Classification of Renal Allograft Pathology is an internationally accepted standard for the assessment of renal allograft biopsies sponsored by the International Society of N ephrology Commission of Acute Renal Failure. The classification had its origins in a meeting held in Banff, Alberta, in the Canadian Rockies, in August, 1991, where subsequent meetings have been held every 2 years. Hot topics likely to influence the Banff Classification of Renal Allograft Pathology in 1999 and beyond are shown in Figs. Prerenal azotemia FIGURE 10-2 Diagnosis of rejection in the Banff classification makes use of two basic lesions, tubulitis and intimal arteritis. The 1993–1995 Banff classification depicted in this figure is the standard in use in virtually all current clinical trials and in many individual transplant units. In this construct, rejection is regarded as a continuum of mild, moderate, and severe forms. The 1997 Banff classification is similar, having the same threshold for rejection diagnosis, but it recognizes three different histologic types of acute rejection: tubulointersititial, vascular, and transmural. The quotation marks emphasize the possible overlap of features of the various types (eg, the finding of tubulitis should not None Borderline M ild M oderate Severe Rejection dissuade the pathologist from conducting a thorough search for intim al arteritis). No tubulitis FIGURE 10-3 Tubulitis is not absolutely specific for acute rejection. It can be found in m ild form s in acute tubular necrosis, norm ally functioning kidneys, and in cyclosporine toxicity and in conditions not related to rejection. The num ber of lym phocytes situated between and beneath tubular epithelial cells is com pared with the num ber of tubular cells to determ ine the severity of tubulitis. Four lym phocytes per m ost inflam ed tubule cross sec- tion or per ten tubular cells is required to reach the threshold for diagnosing rejection. In this figure, the two tubule cross sections in the center have eight m ononuclear cells each. Rejection with intim al arteritis or transm ural arteritis can occur without any tubulitis whatsoever, although usually in well-established rejection both tubulitis and intim al arteritis are observed.
Tis is one way of making progress towards universal health coverage generic 20 mg micardis, and MDG best 80 mg micardis, Millennium Development Goal cheap micardis 20mg with visa. Te challenge Reproduced, by permission of the publisher, from ahead is to ensure that funds and other resources Tayler-Smith et al. Further research is 78 Chapter 3 How research contributes to universal health coverage needed on cost–efectiveness and how to adapt health outcomes, particularly for poorer popu- such interventions to diferent settings. Studies from Brazil, Colombia, Honduras, Main conclusions Malawi, Mexico and Nicaragua were included. With regard to other health out- improve the use of health services comes, mothers reported a 20–25% decrease in the probability of children under three years of and health outcomes: a systematic age being ill in the previous month. Schoolgirls and young women aged ments to households on the condition that they 13–22 years were randomly allocated monthly comply with certain predetermined require- cash payments or nothing at all. Tose receiv- ments in relation to health care or other social ing monthly cash payments were further subdi- programmes (Fig. CCT programmes have vided into two groups: those who received the been justifed on the basis that providing sub- payments conditionally (on attending school sidies is necessary to encourage the use of and for 80% of the days that the school was in ses- access to health services by poor people (64). Households received varied amounts of and to increase the demand for and utilization of US$ 4–10 and the amount given to the girl varied health services by reducing or eliminating fnan- in the range US$ 1–5. What is the evidence that enrolled, HIV prevalence 18 months afer enrol- such an approach works? Te prevalence of herpes simplex A systematic review assessed the available evi- virus type 2 (HSV-2) was 0. Tere were no 79 Research for universal health coverage Fig. Identity cards are an integral part of schemes that provide conditional cash transfers in health and education programmes diferences between the conditional and uncon- in the under-fves. In addition, the programme ditional cash transfer groups in HIV or HSV-2 was shown to increase vaccination coverage and prevalence. Tese fndings show that fnancially prenatal visits by mothers and to reduce hospi- empowering schoolgirls might have a benefcial talization rates in the under-fves (66). In Brazil, a country-wide ecological study Towards universal health coverage showed that increased coverage of the Bolsa There is now a substantial body of data show- Familia programme, a national CCT programme ing that CCTs can, under some circumstances, transferring cash to poor households if they have positive effects on nutritional status and comply with conditions related to health and health by increasing the use of health services education, was signifcantly associated with the and by promoting healthy behaviours (13, 67– reduction of mortality (whether from all causes 69). However, CCT schemes do not necessarily or from poverty-related causes) in children work everywhere. Te efect of consolidated variety of factors, such as being able to identify Bolsa Familia coverage was highest on mortal- participating individuals with unique person ity resulting from malnutrition and diarrhoea identifiers (Fig. Te 2003 Mexican health reform legislated There are also limitations to the studies that the System of Social Protection in Health, of have been carried out to date. It is clearly important the frst few years of Seguro Popular, and taking to find the right mix of incentives and regula- advantage of its phased roll-out, it was important tions that affect both the supply of and demand to assess the impact of the intervention on health for services so that CCTs can improve the qual- and fnancial expenditure (70). Study design In a cluster randomized study, 100 pairs of health Main conclusions facility catchment areas (“health clusters”) were ■ CCT schemes serve as fnancial incentives randomly assigned to receive either the inter- for increasing the demand for and utili- vention or the control. Te intervention, Seguro zation of health services by reducing or Popular, provided a package of benefts that eliminating fnancial barriers to access. Tere were also service utilization which leads to improved funds to cover catastrophic health expenditures health outcomes. In health clus- ters receiving the intervention, there was a cam- paign to persuade every family to enrol in Seguro Case-study 11 Popular. In the matched control cluster families received the usual health care which they had Insurance in the provision to pay for (14).
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