C. Arakos. University of Toledo.
Nonetheless discount speman 60 pills fast delivery, Pancreas 30 (13–70) 60% of TSC cases are apparently sporadic purchase 60 pills speman, likely representing new Cysts 40 mutations (most are found in the TSC2 gene). The proteins Microcystic adenoma 4 encoded by the TSC1 and TSC2 genes are called hamartin and Islet cell tumor 2 tuberin, respectively. They likely act as tumor suppressors; their pre- Carcinoma 1 cise cellular role remains largely unknown. VHL is an autosomal-dominant multisystem disorder with a prevalence rate of roughly 1 in 40,000 [32, 35]. It is characterized by the development of tumors, benign and malignant, in various organs. VHL-associated tumors tend to arise at an earlier age and more often are multicentric than the sporadic varieties. M orbidity and mortality are mostly relat- ed to central nervous system hemangioblastoma and renal cell carci- noma. Involvement of cerebellum, retinas, kidneys, adrenal glands, and pancreas is illustrated (see Figures 9-37 to 9-41). The VH L gene is located on the short arm of chrom osom e 3 and exhibits characteristics of a tum or suppressor gene. M utations are now identified in 70% of VH L fam ilies. FIGURE 9-37 Von H ippel-Lindau disease (VH L): central nervous system involve- m ent. Gadolinium -enhanced brain m agnetic resonance im age of a patient with VH L, shows a typical cerebellar hem angioblastom a, appearing as a highly vascular nodule (arrow) in the wall of a cyst (arrowheads) located in the posterior fossa. H em angioblastom as are benign tum ors whose m orbidity is due to m ass effect. Cerebellar hem angioblastom as m ay present with sym ptom s of increased intracranial pressure. Spinal cord involvem ent m ay be m anifested as syringom yelia. O cular fundus, A, and corre- sponding fluorescein angiography, B, in a patient with VH L, shows two typical reti- nal hem angioblastom as. The sm aller tum or (arrow) appears at the fundus as an intense red spot, whereas the larger (arrow heads) appears as a pink-orange lake with dilated, tortuous afferent and efferent vessels. Sm all peripheral lesions are usually asym pto- m atic, whereas large central tum ors can im pair vision. FIGURE 9-39 Gadolinium -enhanced abdom inal m agnetic resonance im age of a Von H ippel-Lindau disease (VH L): kidney involvem ent. Contrast- patient with VH L shows bilateral pheochrom ocytom a (arrows). Renal involvem ent of VH L includes cysts (sim ple, Pheochrom ocytom a m ay be the first m anifestation of VH L. It atypical, and cystic carcinom a) and renal cell carcinom a [36, 37]. Both cystic involvem ent and sequelae of surgery can lead to renal failure. Contrast- enhanced abdominal CT in a patient with VHL shows multiple cysts in both pancreas (especially the tail, arrows) and kidneys. The major- ity of pancreatic cysts are asymptomatic. W hen they are numerous and large, they can induce diabetes mellitus or steatorrhea. Other, rare pancreatic lesions include microcystic adenoma, islet cell tumor, and carcinoma. FIGURE 9-42 VHL: SCREENING PROTOCOL Von H ippel-Lindau disease. As m ost m anifestations of VH L are potentially treatable, periodic exam ination of affected patients is strongly recom m ended. Though genetic testing is now very useful Study Affected persons Relatives at risk for presym ptom atic identification of affected persons, it m ust be rem em bered that a m utation in the VH L gene currently is detected Physical examination Annual Annual in only 70% of families. For persons at risk in the remaining families, 24-h Urine collection for Annual Annual a screening program is also proposed. Contrast-enhanced CT in a 35- year-old m an with M CD. M CD is a very rare autosomal-dominant disorder characterized by medullary cysts detectable by certain im aging techniques (preferably com puted tom ography) and progressive renal im pairm ent leading to end- stage disease between 20 and 40 years of age. Dom inant inheri- tance and early detection of kidney cysts distinguish M CD from autosom al-recessive nephronophthisis (see Fig. A B m ultiple cysts, typically sm all cortical ones. Am ong the fam ilial cases, som e patients are infants who have early-onset auto- FIGURE 9-44 som al-dom inant polycystic disease.
Evalua- tiple chemical neurotransmitter systems that play roles in tion of the emotional salience of a stimulus involves ap- fear and anxiety behavior cheap speman 60pills. The anatomic circuits where these praisal of its valence (e discount 60 pills speman mastercard. Emotional expression conveys the range of behavioral, selectivity of lesion analyses in experimental animals, and endocrine, and autonomic manifestations of the emotional by advances in neuroimaging technology, which have per- response, whereas emotional experience describes the sub- mitted mapping of the neurophysiologic correlates of emo- jective feeling accompanying the response. The findings of these investigations have their capacity for guiding behavior, all these aspects of emo- informed the design and interpretation of clinical neurosci- tional processing are modulated by complex neurobiological ence approaches aimed at investigating how dysfunction systems that prevent them from becoming persistent, exces- within these neurochemical and anatomic systems may re- sive, inappropriate to reinforcement contingencies, or other- sult in psychiatric conditions such as panic, posttraumatic wise maladaptive. This chapter reviews the pre- The emotional processes pertaining to fear and anxiety clinical and clinical data regarding the neural mechanisms that have been most extensively studied (largely because of underlying normal and pathologic anxiety and discusses their amenability to experimental manipulation) have in- their implications for guiding development of novel treat- volved pavlovian fear conditioning and fear-potentiated ments for anxiety disorders. These types of 'fear learning' have been shown to comprise experience-dependent forms of neural plasticity in an extended anatomic network that centers around the NEUROANATOMIC CIRCUITS SUPPORTING critical involvement of the amygdala (1,6). The structures FEAR AND ANXIETY that function in concert with the amygdala during fear learning include other mesiotemporal cortical structures, the Fear and anxiety normally comprise adaptive responses to sensory thalamus and cortices, the orbital and medial pre- threat or stress. These emotional-behavioral sets may arise frontal cortex (mPFC), the anterior insula, the hypothala- in response to exteroceptive visual, auditory, olfactory, or mus, and multiple brainstem nuclei (1,5,7). Much of this somatosensory stimuli or to interoceptive input through the network appears to participate in the general process of asso- viscera and the endocrine and autonomic nervous systems. Charney: Mood and Anxiety Disorder Research Program, National Institute of Mental Health, Bethesda, Maryland. Drevets: Section on Mood and Anxiety Disorders Imaging, Molec- ular Imaging Branch, National Institute of Mental Health, Bethesda, Mary- The anatomic systems supporting fear learning are organ- land. The projections from sensory thalamus to the LA are The former processes depend on monosynaptic projections thought to support rapid conditioning to simple visual and from the sensory thalamus to the amygdala, whereas the auditory features, presumably accounting for fear responses latter involve projections from sensory association cortices below the level of conscious awareness (31). Thus, lesioning and mesiotemporal cortical structures to the amygdala (1, the auditory cortex before conditioning does not prevent 12). These neural networks also respond to visceral input conditioning to single auditory tones. In contrast, projec- received both directly through the nucleus paragigantocellu- tions to the LA from the primary sensory and sensory associ- laris and the nucleus tractus solitarius (NTS) of the vagus ation cortices appear to be essential for some aspects of nerve and indirectly through the locus ceruleus (LC), the conditioned responding to more complex sensory stimuli (4, anterior insula, and the infralimbic and prelimbic cortices 32). Finally, neural activity within the amygdala is disruption of the projections from the auditory thalamus modulated by cortisol, norepinephrine (NE), and other and auditory cortex to the LA specifically prevents acquisi- neurotransmitters and by mnemonic input related to previ- tion of fear conditioning to auditory stimuli and fear-condi- ous conditioning and reinforcement experiences conveyed tioned responses to previous auditory CSs (33–35). The most extensive extranuclear projections of are responsive to auditory, visual, and somatic stimuli, thus the LA are composed of reciprocal projections to the basal enabling the LA to serve as a locus of convergence for infor- and accessory basal nuclei and the central nucleus of the mation about CS and US (19). Olfactory input, in contrast, amygdala (CE) (37,38). Lesions of either the LA or the directly projects to the periamygdaloid cortex from the ol- CE—but not of other amygdala nuclei—disrupt fear condi- factory bulb through the olfactory tract (20). The olfactory tioning to a tone CS, a finding suggesting that this direct tract also sends projections to the pyriform cortex and the projection from LA to CE is sufficient to mediate condition- entorhinal cortex, areas with reciprocal connections to the ing to simple sensory features (4). Although the periamygdaloid cortex neu- The projections from LA to the basal amygdaloid nuclei rons project to deeper amygdaloid nuclei, the specific path- also participate in forming long-lasting memory traces for ways conveying olfactory information through the amygdala fear conditioning (2,15,39). Functional inactivation of the have not been delineated. The basal nuclei have wide- tions from the hippocampal formation to the amygdala spread intranuclear connections and also project to other through the fornix have been specifically implicated in spa- amygdalar nuclei, including the CE and the LA (41). Thus, lesioning these also share extensive, reciprocal projections with the orbital projections specifically prevents fear conditioning to the and mPFC (43). The basal nuclei are thus anatomically chamber or the position within a maze in which aversive positioned to modulate neuronal responses in both the LA stimulation previously occurred (22–25). Lesions of the latter regions reduce long-term potentiation–like associative processes (6). Plas- fear reactivity to contextual stimuli, but they do not affect ticity related to fear learning also occurs in cortical areas, CS acquisition or response extinction (26). In contrast, le- presumably making possible the establishment of explicit sions placed in the rostral perirhinal cortex after fear condi- or declarative memories about the fear-related event through tioning interfere with the expression of conditioned fear interactions with the medial temporal lobe memory system responses elicited by visual and auditory stimuli when these (44,45). The influence of the amygdala on cortically based stimuli are presented in contexts that differ from the initial memories has been most clearly characterized with respect conditioning context (27). Notably, genetic studies in mice to late plastic components of the auditory cortex neuronal identified a quantitative trait locus for contextual condition- responses to a CS. Single-unit recordings during fear condi- ing (28,29) that was associated with mouse 'emotionality' tioning indicate that some auditory cortex neurons, which in another study (30), although the molecular genetic, neu- before conditioning did not respond to the CS tone, develop Chapter 63: Neurobiological Basis of Anxiety Disorders 903 late-conditioned responses (i. These late-conditioned audi- Human neuroimaging and electrophysiologic and lesion tory cortical neuronal responses take more trials to learn analysis studies have also demonstrated that the amygdala and respond more slowly than LA neurons within trials, is involved in the recall of emotional or arousing memories and their late development is prevented by amygdala lesions. In humans, bursts of electroencephalographic ac- Thus, whereas rapid conditioning of fear responses to po- tivity have been recorded in the amygdala during recollec- tentially dangerous stimuli depends on plasticity in the tion of specific emotional events (56). Moreover, electrical amygdala, learning involving higher cognitive (i. Other auditory cortex neurons show an early (less than Role of the Amygdala in Organizing Emotional 50 milliseconds of stimulus onset) plastic component dur- Expression ing fear conditioning, in which the preexisting electrophysi- ologic responses of auditory cortex neurons to the CS be- The amygdaloid output nuclei, especially the CE, receive come enhanced by conditioning (46). This short-latency convergent information from multiple amygdala regions plasticity within the auditory cortex appears to depend on and generate behavioral responses that are thought to reflect input from the auditory thalamus and is unaffected by the sum of neuronal activity produced by different amygda- amygdala lesions. Nevertheless, such short-latency responses loid nuclei (36).
In a reanalysis of the multi- combined errors of sensitivity and specificity in blindly dis- center efficacy and safety data for clomipramine discount speman 60 pills overnight delivery, Ackerman tinguishing OCDsubjects from controls buy speman 60 pills without prescription. A second study of OCDadolescents for confounds, found a later age at onset to be a strong found a high frequency of age-inappropriate synkinesias and predictor of response. Skoog and Skoog (42) reported that lateralization of deficits to the left side of the body (64). In onset of OCDbefore age 20 was related to a poorer out- a nonblinded study in which a clinical neurologic examina- come, especially in men. In other studies, age at onset did tion was performed in childhood and adolescent OCDsub- not predict severity of illness at follow-up. Adolescents in jects, most of the patients had abnormal neurologic find- the study of Berg et al. It seems likely sided signs that were suggestive of right-sided dysfunction. However, in the only study we could locate that type in OCD. Thus far, specific obsessions and compulsions have not predicted outcome in the vast majority of follow- examined level of functioning in OCD, pretreatment func- up studies. In a preliminary analysis of 544 patients from tioning did not predict follow-up outcome (73). Duration a multicenter trial of acute clomipramine, the authors failed of symptoms was not predictive in any study (78,79,81, to find any significant correlation between symptom sub- 82), although it is possible that chronicity accompanied by type, identified by the Y-BOC Symptom Checklist, and comorbidity may worsen prognosis. However, STABILITY OVER TIME few systematic clinical psychopathologic studies had been completed before 1985. Earlier studies were retrospective The beginning clinician is often struck by the diversity of and failed to utilize standardized diagnostic criteria or relia- the clinical presentations of OCD. During the last 15 years, we have character- ters on whether a psychopathologic continuum exists for ized the phenomenologic and clinical features of more than the two disorders. Some investigators have suggested that 1,000 patients with OCD. The basic types and frequencies obsessions are a preliminary sign of schizophrenia, whereas of obsessive-compulsive symptoms have been found to be others have claimed that obsessional thoughts are a neurotic consistent across cultures and time (84). Why particular defense against psychotic decompensation. Most current re- symptom patterns develop in given persons remains un- searchers feel that the two disorders are different entities known. The most common obsessions include contamina- without any true relationship. If OCDwas closely related to tion, pathologic doubt, aggressive and sexual thoughts, so- schizophrenia, one would expect that schizophrenia would matic concerns, and the need for symmetry and precision. How- The most common rituals are checking, cleaning, and ever, follow-up studies have shown that the incidence of counting. Rosen (85), in a retrospective terms of variation in overall intensity of symptoms, finer chart review of 850 inpatients with schizophrenia, found analyses of variations in symptom focus or symptom mix that approximately 10% exhibited prominent obsessive- have not been attempted. Nevertheless, in their study of compulsive symptoms. This finding was replicated by childhood OCD, Swedo and Leonard (22) reported that Fenton and McGlashan (86), who found that 10% of 90% of patients experienced some change in symptom pat- schizophrenics in a Chestnut Lodge (Rockville, Maryland) tern over time, often starting with a solitary ritual without follow-up study exhibited prominent obsessive-compulsive associated obsessive thoughts (notably uncommon in symptoms. These obsessive-compulsive schizophrenic pa- adults), then later adding new symptoms that sometimes tients tended to have a more chronic course and a greater became predominant over earlier ones. More work is needed frequency of social or occupational impairment in compari- to delineate the frequency and magnitude of the cyclic varia- son with a matched sample of schizophrenics without obses- tions in intensity and focus of obsessive-compulsive symp- sive-compulsive features. The average Y-BOCS score for those meeting the criteria COMORBIDITY for OCDwas 22. The relationship between obsessions, compulsions, and Biological markers and neuropharmacologic challenge stud- depression was the subject of several early studies. These ies depend on the selection of homogeneous clinical popula- were primarily retrospective and failed to use diagnostic cri- tions that reduce the variance. In studying a disorder like teria or structured interviewing. Thus, many aspects of the OCD, the presence of other axis I disorders is a serious association between depression and OCDremain unclear. The majority (57%) of OCDpatients present- tive episodes in OCDare primary or secondary. Dividing ing to our clinic have at least one other DSM-III-R diagno- depressed obsessional patients into these two categories (i. To complicate matters further, OCDis a chronic illness, primary and secondary) was originally advocated by Lewis and an even higher percentage of our patients have a lifetime (24). No systematic study of the frequency of obsessions history of another axis I disorder.
Coprolalia (the uttering of unacceptable words) is of public interest order speman 60pills overnight delivery, but occurs in <10% of those with tic disorder generic speman 60pills. An MRI study of boys with Tourette syndrome (Roessner et al, 2010) shows bilateral increased volume of putamen (which may reflect dopaminergic dysfunction or neuroimmunologic alterations) and sub-region of the corpus callosum (which may be the consequence of daily tic disorder). Management includes behavioural therapy and low dose haloperidol. Depression occurring in children and adolescents may have an atypical presentation with irritability rather than apparent depressed mood. Eating and sleeping may increase rather than decrease. Initial treatment should be psychological, except in severe cases. Mania and schizophrenia are encountered, and early treatment is believed to improve the outcome. Lithium and antipsychotics should be used as necessary. Internet addiction is recently described but diagnostic criteria are yet to be universally accepted. Using functional MRI, internet addiction may be associated with a widespread and significant decrease of functional connectivity in cortico-striatal circuits, in the absence of global changes in brain functional network typology (Hong et al, 2013). Prevalence of autism spectrum disorders – Autism and Developmental Disabilities Monitoring Network, 14 sites, United States. Attention-deficit/hyperactivity disorder without comorbidity in associated with distinct atypical patterns of cerebral microstructural development. Hum Brain Mapp 2013 Aug 1 [Epub ahead of print] Ainsworth M. Patterns of attachment: a psychological study of the strange situation. Lawerence Erlbaum Associates, 1969 ISBN 0898594618 Bowlby J. A secure base: parent-child attachment and health human development. Candidate gene studies in child psychiatric disorders. A cross-national profile of bullying and victimization among adolescents in 40 countries. International Journal of Public Health 2009; 54: 216-224. Risk of separation anxiety disorders among girls: paternal absence, socioeconomic disadvantage, and genetic vulnerability. Prenatal maternal stress programs infant stress regulation. A twin study of anxiety related behaviours in pre-school children. Journal of Child Psychology and Psychiatry 2003; 44:945-960. Meta-analysis of the association between the 7-repeat allele of the dopamine D4 receptor gene and attention deficit hyperactivity disorder. Biological Psychiatry 2009; Apr 30 [Epub ahead of print] Froehlich W, Cleveland S, Torres A, et al. Head circumferences in twins with and without autism spectrum disorders. Pharmacologic intervention for attention-deficit hyperactivity disorder in preschoolers: is it justified? A retrospective foetal ultrasound study of brain size in autism. Decreased functional brain connectivity in adolescents with internet addiction. Pediatric generalized anxiety disorder: epidemiology, diagnosis and management. Parental age and risk of autism spectrum disorders in a Finnish national birth cohort. Journal of Autism and Dev Disord 2013; in press Lindberg T, Wadsby M. Psychiatric and somatic health in relation to experience of parental divorce in childhood. International Journal of Social Psychiatry 2010 Sep 17 [Epub ahead of print] McCleery J, Allman E, Carver L, Dobkins K. Abnormal magnocellular pathway visual processing in infants at risk for autism. Altered white matter fractional anisotropy and social impairment in children with autism spectrum disorder. Brain Research 2010 Sept 18 [Epub ahead of print] Ptacek R.
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