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Proliferation and telomere length in acutely mobilized blood mononuclear cells in HIV infected patients.

The aim of the study was to investigate the mobilization of T cells in response to a stressful challenge (adrenalin stimulation), and to access T cells resided in the peripheral lymphoid organs in HIV infected patients. Seventeen patients and eight HIV seronegative controls received an adrenalin infusion for 1 h. Blood was sampled before, during and 1 h after adrenalin infusion. Proliferation and mean telomere restriction fragment length (telomeres) of blood mononuclear cells (BMNC) and purified CD8+ and CD4+ cells were investigated at all time points. In patients, the proliferation to pokeweed mitogens (PWM) was lower and decreased more during adrenalin infusion. After adrenalin infusion the proliferation to PWM was restored only in the controls. In all subjects telomeres in CD4+ cells declined during adrenalin infusion. Additionally, the patients had shortened telomeres in their CD8+ cells, and particularly HAART treated patients had shortened telomeres in all cell-subtypes. The finding that patients mobilized cells with an impaired proliferation to PWM during and after adrenalin infusion has possible clinical relevance for HIV infected patients during pathological stressful conditions, such as sepsis, surgery and burns. However, this study did not find a correlation between impaired proliferation and telomeres. It is concluded that physiological stress further aggravates the HIV-induced immune deficiency.

Adult↗

Imaging of the small airways.

Small airways disease (SAD) is defined as a pathologic condition in which the small conducting airways are affected either primarily or as part of other pulmonary changes. Diagnosis is often difficult because the many histopathologic subtypes that have been described often lack obvious clinical or imaging correlates and because widespread involvement is needed before clinical symptoms and abnormalities on pulmonary function testing occur. High-resolution computed tomography (HRCT) can be helpful to detect, characterize, and quantify small airways involvement. These airways may become visible directly when inflammation of the bronchiolar wall and accompanying exudates develop. Obstruction of the small airways may be detected indirectly by HRCT when it causes regional underventilation resulting in reduced perfusion. This article discusses the direct and indirect HRCT signs of small airways involvement and, based on the fundamental differences between these signs, gives a short review of the HRCT features of the most important diseases that can affect the small airways.

Journal Article↗

Recovery and rehabilitation following subarachnoid haemorrhage. Part I: Outcome after inpatient rehabilitation.

BACKGROUND AND PURPOSE: Although subarachnoid haemorrhage (SAH) is a subtype of stroke, functional outcome following rehabilitation for SAH must be considered distinct from that of cerebral infarction because of the younger age and the difference in pathology and resultant neurologic deficits. The purposes of this study were to: (1) describe the demographic and clinical characteristics of SAH patients receiving rehabilitation; (2) describe functional outcomes following inpatient rehabilitation; and (3) investigate possible relationships between patient characteristics and functional outcomes. METHODS: Retrospective chart review of SAH patients admitted to inpatient rehabilitation. Functional Outcomes rated by the Functional Independence Measures (FIM). Analysis with descriptive and nonparametric statistics. RESULTS: Eighty patients with SAH admitted to a rehabilitation unit with a mean age of 54 years. Fifty-seven had identified aneurysms as a cause of SAH. Seventy-four subjects (93%) presented with Hunt and Hess grades of 3-5. The median length of stay was 26 days in acute care and 49 days in rehabilitation. Seventy patients (88%) were discharged home. The mean admission FIM was 59.5 and mean discharge FIM 91.0. The FIM efficiency (aggregate change in FIM/day) was 0.62/day and the average rate of FIM gain 0.97 points/day. Hydrocephalus negatively influenced outcome (p = 0.05). There was a trend for subjects with worse Hunt and Hess scores at onset to have poorer discharge FIM scores. CONCLUSION: SAH patients receiving inpatient rehabilitation make functional gains, although the rate of gain is less than for TBI or stroke. These SAH patients represent a subgroup with more severe SAH at onset than the total population of SAH survivors. The presence of hydrocephalus negatively impacts on outcome. Further detailed study of functional and neuropsychological outcome in SAH survivors is needed.

Activities of Daily Living↗

Genetics of multiple sclerosis: determinants of autoimmunity and neurodegeneration.

Since the first description of multiple sclerosis (MS) as an inheritable disease by Eichhorst [1] accumulating epidemiological observations support a genetic hypothesis. Population, family and twin studies have revealed that Mendelian transmission of a single susceptibility gene would not be compatible with the observed patterns of inheritance. Like most other common diseases, MS is a complex trait, defined by several genes, each probably exerting a relatively small effect. Complex interactions among susceptibility genes and the environment are believed to contribute to a predisposition to dysregulation of inflammatory pathways, demyelination and tissue degeneration in the central nervous system (CNS). Natural history and pathological studies, however, define that MS represents a spectrum rather than a single entity of inflammatory demyelination. Despite a growing need for identifying molecular markers of biological subtypes of MS, only limited information is available for genotype-phenotype correlations. Four full genome scans using polymorphic microsatellite markers in nuclear and multiplex MS families indicated several chromosomal regions of susceptibility. With the recently discovered, highly abundant single nucleotide polymorphisms (SNPs) and family-based association methods, the means are now available to confine these relatively large regions of interest to candidate genes and susceptibility alleles. The currently available SNP maps favor indirect association studies based on linkage disequilibrium between marker and disease alleles. Here, we review available genetic data in MS, and introduce an additional strategy which correlate genetic markers with major biological components of the disease such as autoimmunity and neurodegeneration. This approach may yield important insights with utility in clinical practice.

Autoimmunity↗

Tubo-ovarian abscess occurring 16 years after supracervical hysterectomy.

BACKGROUND: Supracervical hysterectomy is seldom performed and there are few reports of tubo-ovarian abscess (TOA) after supracervical hysterectomy. CASE: The case of a 49-year-old woman with a right TOA is reported. This patient had received a supracervical hysterectomy 16 years earlier due to rupture of the uterus. At this admission, she presented with complaints of, lower abdominal pain and fever. Bimanual and transvaginal ultrasound examinations demonstrated a tender mass in the right adnexal region. Laparotomy, pathologic examination and microbiologic study confirmed the diagnosis of right TOA. CONCLUSION: After supracervical hysterectomy, patients may develop endocervicitis, parametritis and/or TOA. This series may be a subtype of ascending infections in the female genital tract.

Abscess↗

Adenoid cystic carcinoma of the sinonasal tract: treatment results.

OBJECTIVES: Malignancies arising from the sinonasal tract, which includes the nose, paranasal sinuses, and nasopharynx, are uncommon. Although adenoid cystic carcinoma (ACC) is the second most common cancer occurring in the sinonasal tract, only few studies have been reported. This retrospective review was performed to identify the clinical features and treatment outcomes of sinonasal ACC. METHODS: Thirty-five patients diagnosed and treated for ACC of the sinonasal tract were included in this study. Medical records, radiographs, and pathologic slides were retrospectively reviewed. RESULTS: In two thirds of the patients, the maxillary sinus was the site of origin and cribriform was the most common histologic subtype (61%). Seventy-one percent of the patients had advanced disease (T3, T4) at the time of diagnosis. Five-year overall survival rate was 86% and treatment failure occurred in 18 patients (51%). Five-year local recurrence rate and distant metastasis rate were 30% and 25%, respectively. Adjunctive radiotherapy appeared to reduce local recurrence. Presence of distant metastasis correlated with decreased 5-year survival (P = .001). Five-year survival rate after development of distant metastasis or local recurrence were 17% and 58%, respectively. CONCLUSIONS: Based on our findings, we suggest that sinonasal ACC be treated by a combined modality of radical surgery followed by postoperative radiation. The prognosis of sinonasal ACC seems to be determined by the presence of distant metastasis.

Carcinoma, Adenoid Cystic↗

Primary gastrointestinal lymphomas: a radiological-pathological review. Part 1: Stomach, oesophagus and colon.

Primary gastrointestinal lymphomas are most common in the stomach, followed by small intestine and then colon. The most frequently used pathology classification of lymphomas is the Revised European and American Lymphoma /World Health Organization classification. The correlation of radiological morphology with histology is relatively poor, although characteristic subtypes will be discussed. In the stomach, the majority of primary lymphomas are of B-cell origin of mucosa-associated lymphoid tissue (MALT) type. Low-grade MALT lymphomas are associated with Helicobacter pylori infection and often respond to eradication of this organism. Radiological features include thickened folds, nodularity, depressed lesions, ulcers, prominent areae gastricae. High-grade (large B-cell) tumour patterns include infiltrative, polypoid, nodular, ulcerated or a combination. Endoscopy, endoscopic ultrasound and CT are important in diagnosis and staging, although appearances on barium studies should be recognized. Primary colonic lymphomas are rare. Most are of B-cell origin. Focal and diffuse forms are seen, the former producing polypoid or nodular or cavitating masses and the latter producing ulcerative or nodular (polyposis) patterns on imaging. Even when circumferential, lymphoma rarely causes obstruction. Small bowel lymphomas will be discussed in the forthcoming part 2 of this review.

Barium Sulfate↗

Activation of P2X receptors for adenosine triphosphate evokes cardiorespiratory reflexes in anaesthetized rats.

1. We tested the hypothesis that activation of P2X receptors associated with vagal afferent nerves can evoke a Bezold-Jarisch (B-J) depressor reflex in anaesthetized rats. 2. Injection of alphabeta-methylene ATP (alphabeta-MeATP; 0.6-600 nmol i.v.) evoked a dose-dependent B-J reflex comprising bradycardia, hypotension and apnoea in rats anaesthetized with pentobarbitone. Apnoea was commonly preceded by hyperventilation. Bilateral vagotomy significantly reduced the bradycardia and most of the apnoeic response without affecting hyperventilation, and unmasked a vasopressor response. Hypotension and apnoea were subject to desensitization, and ATP was about 100 times less potent than alphabeta-MeATP in evoking the B-J reflex. 3. ED50 values for responses to alphabeta-MeATP were: bradycardia 14.6 +/- 3.8 nmol; apnoea 47.1 +/- 8.5 nmol; hyperventilation 23.3 +/- 6.0 nmol, n = 14. The ED50 for apnoea was significantly greater than that for bradycardia or hyperventilation (P < 0.05). Atropine (2.8 micromol (kg body wt)-1 i.v.) antagonized the reflex bradycardia and hypotension. 4. The P2 antagonists suramin (14 micromol (kg body wt)-1 i.v.) and PPADS (17 micromol (kg body wt)-1 i.v.) antagonized the bradycardic and apnoeic components of the reflex response to alphabeta-MeATP, without reducing the vasopressor or hyperventilatory responses to the agonist. 5. Recordings from vagal afferents showed that pulmonary inflation receptors were activated by alphabeta-MeATP in 62 % of units recorded (ED50 22 +/- 5 nmol) and this was blocked by PPADS (17 micromol (kg body wt)-1 i.v.); unidentified vagal afferents were also activated. 6. alphabeta-MeATP activated carotid chemoreceptor afferents (ED50 23 +/- 9 nmol), an action that was unaffected by PPADS or suramin. 7. The results support the hypothesis that P2X receptor subtypes for ATP are associated with specific sensory nerves that form part of the homeostatic mechanism for cardiovascular and respiratory regulation and these receptors therefore have physiological, pathological and therapeutic significance.

Adenosine Triphosphate↗

Pharmacology of brain Na+/Ca2+ exchanger: from molecular biology to therapeutic perspectives.

In the last two decades, there has been a growing interest in unraveling the role that the Na+/Ca2+ exchanger (NCX) plays in the function and regulation of several cellular activities. Molecular biology, electrophysiology, genetically modified mice, and molecular pharmacology have helped to delve deeper and more successfully into the physiological and pathophysiological role of this exchanger. In fact, this nine-transmembrane protein, widely distributed in the brain and in the heart, works in a bidirectional way. Specifically, when it operates in the forward mode of operation, it couples the extrusion of one Ca2+ ion with the influx of three Na+ ions. In contrast, when it operates in the reverse mode of operation, while three Na+ ions are extruded, one Ca2+ enters into the cells. Different isoforms of NCX, named NCX1, NCX2, and NCX3, have been described in the brain, whereas only one, NCX1, has been found in the heart. The hypothesis that NCX can play a relevant role in several pathophysiological conditions, including hypoxia-anoxia, white matter degeneration after spinal cord injury, brain trauma and optical nerve injury, neuronal apoptosis, brain aging, and Alzheimer's disease, stems from the observation that NCX, in parallel with selective ion channels and ATP-dependent pumps, is efficient at maintaining intracellular Ca2+ and Na+ homeostasis. In conclusion, although studies concerning the involvement of NCX in the pathological mechanisms underlying brain injury during neurodegenerative diseases started later than those related to heart disease, the availability of pharmacological agents able to selectively modulate each NCX subtype activity and antiporter mode of operation will provide a better understanding of its pathophysiological role and, consequently, more promising approaches to treat these neurological disorders.

Animals↗

Signet-ring cell or mucinous histology after preoperative chemoradiation and survival in patients with esophageal or esophagogastric junction adenocarcinoma.

PURPOSE: The survival of patients with local-regional adenocarcinoma of the esophagus or esophagogastric junction (EGJ) treated with preoperative chemoradiation is much better in patients with pathologic complete response than those with residual tumor. Some adenocarcinomas have mixed patterns, including signet-ring cell and mucinous histology, but the clinical significance of these subtypes is unknown. EXPERIMENTAL DESIGN: We studied 412 consecutive patients with esophageal or EGJ adenocarcinoma treated with chemoradiation followed by esophagectomy (193 patients) or surgery alone (219 patients). We evaluated signet-ring cell and mucinous histology in the resection and pretherapy biopsy specimens and compared clinicopathologic features with overall survival. RESULTS: The fraction of signet-ring cell and mucinous histology was similar in evaluated specimens of patients treated with preoperative chemoradiation or surgery alone (17% and 18%, respectively). The overall survival rate at 5 years of patients treated with preoperative chemoradiation was significantly better if residual signet-ring cell or mucinous histology was present in the esophagectomy specimen (63% versus 28%; P = 0.02). All 13 patients with acellular mucin pools and no residual carcinoma are still alive after an average follow-up time of 36 months. By contrast, in patients treated with surgery alone, overall survival rate was significantly worse if signet-ring cell or mucinous histology was present (14% versus 30%; P = 0.05). In multivariate analysis, overall survival was independently predicted by presence of signet-ring cell or mucinous histology (P = 0.04). CONCLUSIONS: Our study showed that patients with esophageal or EGJ adenocarcinoma who have signet-ring cell or mucinous histology benefited substantially from preoperative chemoradiation and esophagectomy.

Adenocarcinoma, Mucinous↗

Prospective prevalence of pathologic gambling and medication association in Parkinson disease.

The authors prospectively screened 297 patients with Parkinson disease (PD), who attended a tertiary clinic, using a modified South Oaks Gambling Scale. Lifetime prevalence of pathologic gambling (PG) was 3.4% and on any dopamine agonist was 7.2%. PG was associated with earlier PD onset and with dopamine agonists but not with agonist subtype or doses. We found no association with a potent D3 receptor agonist.

Aged↗

AM-3K, an anti-macrophage antibody, recognizes CD163, a molecule associated with an anti-inflammatory macrophage phenotype.

CD163 is a member of the scavenger receptor cysteine-rich superfamily restricted to the monocyte/macrophage lineage and is thought to be a useful marker for anti-inflammatory or alternatively activated macrophages. In this study we used mass spectrometric analysis to determine that the antigen recognized by the antibody AM-3K, which we previously generated as a tissue macrophage-specific monoclonal antibody, was CD163. An anti-inflammatory subtype of macrophages stimulated by dexamethasone or interleukin-10 showed strong reactivity for AM-3K and increased expression of CD163 mRNA. Immunohistochemical staining of routinely processed pathological specimens revealed that AM-3K recognized a specialized subpopulation of macrophages. In granulomatous diseases such as tuberculosis, sarcoidosis, or foreign body reactions, tissue macrophages around granulomas, but not component cells of the granulomas such as epithelioid cells and multinucleated giant cells, showed positive staining for AM-3K. In atherosclerotic lesions, scattered macrophages in diffuse intimal lesions were strongly positive for AM-3K, whereas foamy macrophages in atheromatous plaques demonstrated only weak staining. We therefore suggest that, in routine pathological specimens, AM-3K is a useful marker for anti-inflammatory macrophages because these cells can be distinguished from inflammatory or classically activated macrophages. Because AM-3K cross-reacts with macrophage subpopulations in different animal species including rats, guinea pigs, rabbits, cats, dogs, goats, pigs, bovine species, horses, monkeys, and cetaceans, it will have wide application for detection of CD163 in various animals.

Antigens, CD↗

Dendrotoxins: structure-activity relationships and effects on potassium ion channels.

Dendrotoxins are small proteins isolated from mamba (Dendroaspis) snakes. The original dendrotoxin was found in venom of the Eastern green mamba, Dendroaspis angusticeps, and related proteins were subsequently found in other mamba venoms. The dendrotoxins contain 57-60 amino acid residues cross-linked by three disulphide bridges, and they are homologous to Kunitz-type serine protease inhibitors, such as aprotinin (BPTI). The dendrotoxins have little or no anti-protease activity, but they block particular subtypes of voltage-dependent potassium channels of the Kv1 subfamily in neurones. Alpha-dendrotoxin from green mamba Dendroaspis angusticeps and toxin I from the black mamba Dendroaspis polylepis block cloned Kv1.1, Kv1.2 and Kv1.6 channels in the low nanomolar range; toxin K, also from the black mamba Dendroaspis polylepis, preferentially blocks Kv1.1 channels and is active at picomolar concentrations. Structural modifications and mutations to dendrotoxins have helped to define the molecular recognition properties of different types of K+ channels, although more work is needed to characterise the chemical features of the toxins that underlie their selectivity and potency at particular subtypes of channels. Dendrotoxins have been useful markers of subtypes of K+ channels in vivo, and dendrotoxins have become widely used as probes for studying the function of K+ channels in physiology and pathophysiology. With some pathological conditions being associated with voltage-gated K+ channels, analogues of dendrotoxins might have therapeutic potential.

Amino Acid Sequence↗

Development of ligands for the peripheral benzodiazepine receptor.

The peripheral benzodiazepine receptor (PBR) initially characterised as a high affinity binding site for diazepam, is densely distributed in most peripheral organs whilst only moderately expressed in the healthy brain. The predominant cell type expressing the PBR at regions of central nervous system (CNS) pathology are activated microglial cells. Under neuroinflammatory conditions there is an over-expression of PBR binding sites indicating that measurements of PBR density can act as a useful index of brain disease activity. The PBR is now considered a significant therapeutic and diagnostic target which has provided the impetus for PBR ligand development. There are several classes of PBR ligands available including benzodiazepines (Ro5-4864), isoquinoline carboxamides (PK 11195), indoleacetamides (FGIN-1-27), phenoxyphenyl-acetamides (DAA1106) and pyrazolopyrimidines (DPA-713). Subsequent conformationally restrained isoquinoline and indoleacetamide analogues have been synthesised in an attempt to yield PBR ligands with superior affinity and brain kinetics. Even though the PBR has been linked to a number of biochemical processes, including cell proliferation, apoptosis, steroidogenesis, porphyrin transport and immunomodulation, its exact physiological role is yet to be deciphered. Selective PBR ligands with favourable in vivo binding properties and kinetics is required to gain a more complete understanding on the normal functioning of the PBR and the chemical pathways underlying several pathological conditions. Novel PBR ligands with unique binding properties and functional activity may also generate information on the localisation of the PBR and the possibility of PBR subtypes. This review highlights the main classes of PBR ligands to date. In addition the biological activity and therapeutic potential of certain PBR ligands is discussed.

Animals↗

Pineal calcification and subtypes of tardive dyskinesia.

There is evidence that reduced melatonin secretion is associated with the pathophysiology of tardive dyskinesia (TD). To investigate the relationship between melatonin secretion and TD, I evaluated scores of subtypes of TD with CT scan measurements of pineal calcification (PC) size in 77 chronic institutionalized schizophrenic and bipolar patients. There was a significantly greater incidence of pathologically enlarged calcified pineal glands (greater than 1 cm in diameter) in the patients (18.1%) compared to the reported incidence in the literature in nonpsychiatric subjects (1%). In addition, there was a significant association between scores of limb-axial (but not orofacial) dyskinesias and the presence of pathologically enlarged PC (p less than 0.05). These findings support the notion that the pathophysiology of orofacial dyskinesias may be distinct from limb-axial dyskinesias. In addition, since it is possible that a pathologically enlarged calcified pineal gland is associated with reduced melatonin secretion, these findings add further support to implicate decreased melatonin secretion in the pathophysiology of TD. Further studies using direct measurements of plasma melatonin levels are required to define more precisely the relationship between TD and melatonin secretion.

Adult↗

[Clinical characteristics of primary biliary cirrhosis with Sjögren's syndrome of 20 cases].

OBJECTIVE: Primary biliary cirrhosis (PBC) is a chronic non-suppurative destructive cholangitis of unknown etiology. It has been reported that patients with PBC suffer from xerostomia and keratoconjunctivitis at high prevalence and PBC has been shown to be associated with Sjögren's syndrome. This study investigated the relationship between PBC and Sjögren's syndrome. METHOD: 20 cases diagnosed as PBC consented to the evaluation for Sjögren's syndrome which included clinical and serological features, Schirmer's test, measurement of parotid flow rate and labial minor salivary gland biopsy. RESULTS: The main manifestations of PBC are jaundice, pruritus, hepatosplenomegaly. M2 subtype of antimitochondrial antibody is of great specificity for PBC. Many PBC patients are suffering from xerostomia and keratoconjunctivitis sicca but do not have typical serological and pathological presentations of primary Sjögren's syndrome. Corticosteroids and immunosuppressive agents have disappointing effects in the treatment. Ursodeoxycholic acid is effective to certain extent. CONCLUSION: It was indicated that Sjögren's syndrome associated with PBC appears to be a secondary form differing from primary Sjögren's syndrome.

Adult↗

[Current topics in the diagnosis and treatment of malignant fibrous histiocytoma].

Malignant fibrous histiocytoma (MFH) is a tumor about which much remains unknown. The cell origin, molecular mechanism of pleomophism and mechanism of pleomorphic change in a cell undergoing malignant change have not been elucidated. MFH-like histological changes are observed in many bone and cartilage sarcomas, and some renal cell carcinomas and malignant lymphomas. These changes occur in many subtypes of sarcomas such as osteogenic sarcoma, chondrosarcoma, leiomyosarcoma, rhabdomyosarcoma, and liposarcoma. MFH has been regarded as one tumor classification from its special histopathological features. In clinical pathological studies these tumors are divided into low-grade fibrous tumors and fibrous histiocytic tumors. With the establishment of molecular biological diagnostic methods, MFH-like histological features can be seen in changes in cellular differentiation of many sarcomas. Patients with MFH often have repeated recurrences before a diagnosis is made, and the tumor is partially resected. Furthermore, distance metastasis develops and the prognosis is poor. The sensitivity of MFH to radiotherapy and chemotherapy is insufficient, and evidence is lacking for adjuvant treatment. Rescue following initial treatment failure is extremely difficult. Local control of 70% to 90% can be achieved if a correct diagnosis is made, and a curative wide resection or salvage wide resection are done early. For treatment of bone and soft tissue sarcoma, a correct diagnosis and initial treatment are extremely important. MFHs are rare tumors that occur in every part of the body. Many cases need to be accumulated in joint clinical studies across fields according to organ and specialty, and effective treatment method developed. We need to advance the standardization of treatment for MFH, and eliminate wrong initial treatment through the active provision of information.

Antineoplastic Combined Chemotherapy Protocols↗

5-Hydroxytryptamine receptors. An example for the complexity of chemical transmission of information in the brain.

Since serotoninergic axon terminals (the cell bodies of which are mainly located in the raphe nuclei of the brain stem) innervate virtually all brain regions, it is intelligible that the serotoninergic system is involved in many physiological and pathological cerebral functions. The marked heterogeneity of the serotonin (5-hydroxytryptamine, 5-HT)receptors and the differences in distribution of the various 5-HT receptor types and subtypes within the brain makes serotoninergic neurotransmission in the brain very complex. This complexity of chemical transmission of information is a prerequisite for the development of drugs which may specifically influence certain cerebral functions, but which do not mimic or block other effects of 5-HT, thus making it possible to reduce or even avoid undesired side effects. The current classification scheme of 5-HT receptors is based on the integration of results of pharmacological, biochemical, electrophysiological and molecular investigations. The multiplicity of 5-HT receptors can be incorporated into the scheme of two main receptor families, i.e. 1. the G protein receptor family, comprising, among the 5-HT receptors, the 5-HT1 and 5-HT2 subtypes and the 5-HT4 type, and 2. the ligand gated ion channels to which (at least according to the current knowledge) only one 5-HT receptor, the 5-HT3 type, belongs. The three 5-HT1 subtypes and the two 5-HT2 subtypes of the current classification scheme, but not the 5-HT3 and 5-HT4 receptors, have already been cloned.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗