Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “subtype”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 955 records · Page 53Linked to original sources

Neurobiological effects of bisphenol A may be mediated by somatostatin subtype 3 receptors in some regions of the developing rat brain.

Considerable attention has been focused on environmental disruptors such as the xenoestrogen bisphenol A, which influences reproductive, developmental, and cognitive activities through its interaction with specific neuromediating systems in an estrogen-like fashion. In the present study, the effects of this xenoestrogen proved to be preferentially directed toward hypothalamic and extrahypothalamic somatostatin receptor subtype 3, which displayed a higher binding affinity of its specific nonpeptide agonist L-796-778 than that of L-779-976 (subtype 2). One type of action, with respect to animals treated with vehicle alone, consisted of a very strong (p < 0.001) decrease of somatostatin receptor subtype 3 mRNA levels in layer V of the frontoparietal cortex of adult rats (Sprague-Dawley) after transplacental and lactational exposure to bisphenol A (400 microg/kg/day). Similarly, such treatment in 7-day-old rats was responsible for a very strong reduction of the subtype 3 mRNA levels in the hypothalamic periventricular nuclei and a strong (p < 0.01) increase of the subtype 3 mRNA levels in the ventromedial nuclei. Moreover, even greater upregulated and downregulated activities were reported when subtype 3 mRNA levels were determined in the presence of receptor agonists specific for distinct alpha GABA(A) receptor subunits (alpha(1,5)). The predominant effects of bisphenol A on somatostatin receptor subtype 3 mRNA levels occurring in an alpha GABA(A) subunit-dependent manner tend to suggest the early modulatory importance of this environmental disruptor on cross-talking mechanisms that are implicated in the plasticity of neural circuits, with consequential influence on neuroendocrine/sociosexual behaviors.

Air Pollutants, Occupational↗

Use of V3 loop peptide-specific antibody evaluation for subtyping HIV-1: results of a vertical transmission study from São Paulo, Brazil.

Plasma samples obtained from 97 children enrolled in a longitudinal study of HIV-1 perinatal transmission in São Paulo, Brazil, were tested for the presence of specific V3-loop antibodies in order to determine the HIV-1 subtype circulating among them. A set of seven synthetic peptides representative of the predominant HIV-1 subtypes detected in Brazil was employed in an in-house enzyme immunoassay (EIA) using two different protocols, one of which permits identification of high avidity antibodies (HAAb). Using these approaches we were able to detect antibodies in 64 out of 97 children, independently of the HIV-1 infection status, indicating the presence of subtype B in all cases, except one, which could be considered to be of subtype F. Among subtype B cases, half of the samples reacted with the GWGR motif (type W is representative of Brazilian B strains). In the main, concordant results were obtained between peptide-EIA and HIV-1 status among infants, although in several cases of truly HIV-1 infected children, negative results could be observed. Thirteen mother-child pairs and four fathers were also evaluated, and the results confirmed subtype B to be the prevalent one among them, showing similar proportions of P and W types. Taken together, the results obtained identified subtype B (W and P) uniformly among adults and HIV-1 infected children from São Paulo, Brazil, and confirm vertical and sexual transmission of the predominant strains.

AIDS Serodiagnosis↗

Pharmacology of N-, L-, and B-subtypes of nematode nAChR resolved at the single-channel level in Ascaris suum.

Pharmacological experiments on Ascaris suum have demonstrated the presence of three (N-, L-, and B-) subtypes of cholinergic receptor mediating contraction of body wall muscle in parasitic nematodes. In the present study, these ionotropic acetylcholine (ACh) receptors (nAChRs) were activated by levamisole and bephenium under patch-clamp conditions and competitively antagonized by paraherquamide and 2-desoxoparaherquamide. A number of recordings exhibited three separate current amplitude levels, indicating the presence of small, intermediate, and large conductance subtypes of receptor. The mean conductance of the small conductance subtype, G25, was 22 +/- 1 pS; the intermediate conductance channel, G35, was 33 +/- 1 pS; and the large conductance channel, G45, was 45 +/- 1 pS. The small channel was not antagonized significantly by paraherquamide and was identified as the N-subtype. The intermediate channel was preferentially activated by levamisole rather than bephenium and antagonized by paraherquamide: the intermediate channel was identified as the L-subtype. The large conductance channel was preferentially activated by bephenium, antagonized more by 2-desoxoparaherquamde than by paraherquamide and was identified as the B-subtype. These observations reveal that the three channel subtypes have different selectivity for cholinergic anthelmintics. The different selectivity of these compounds should be considered when dealing with drug resistant infections.

Animals↗

Alpha-2A is the predominant alpha-2 adrenergic receptor subtype in human spinal cord.

alpha-2 Adrenergic receptors can be subdivided into four subtypes based on their pharmacologic properties. The subtype of alpha-2 adrenergic receptor present in human spinal cord has not been reported previously. The affinities of nine alpha-2 subtype-selective drugs for the alpha-2 adrenergic receptor in human spinal cord homogenates were determined using [3H]rauwolscine and [3H]RX821002. These drug affinities (pKi values) were highly correlated with those obtained in a tissue or cell line containing only the alpha-2A adrenergic subtype (correlation coefficient of 0.99 and 0.98 for human platelet and HT29 cells, respectively). In contrast, the correlation of pKi values for the human spinal cord with tissues or cell lines containing other adrenergic receptor subtypes was poor. The correlation coefficients for alpha-2B (neonatal rat lung), alpha-2C (OK cell), and alpha-2D (bovine pineal gland) were 0.15, 0.68, and 0.81, respectively. These data suggest that the predominant alpha-2 adrenergic subtype present in human spinal cord is the alpha-2A subtype. Both [3H]rauwolscine and [3H]RX821002 appeared to label a single class of binding sites. The alpha-2 adrenergic receptor density was significantly greater in the sacral region of the cord as compared to either the lumbar or thoracic regions.

Adrenergic alpha-Antagonists↗

Meperidine exerts agonist activity at the alpha(2B)-adrenoceptor subtype.

BACKGROUND: The opioid agonist meperidine has actions, such as antishivering, that are more pronounced than those of other opioid agonists and that are not blocked with nonselective opioid antagonists. Agonists at the alpha(2) adrenoceptors, such as clonidine, are very effective antishivering drugs. Preliminary evidence also indicates that meperidine interacts with alpha(2) adrenoceptors. The authors therefore studied the ability of meperidine to bind and activate each of the alpha(2)-adrenoceptor subtypes in a transfected cell system. METHODS: The ability of meperidine to bind to and inhibit forskolin-stimulated cyclic adenosine monophosphate formation as mediated by the three alpha(2)-adrenoceptor subtypes transiently transfected into COS-7 cells has been tested. The ability of the opioid antagonist naloxone and the alpha(2)-adrenoceptor antagonists yohimbine and RX821002 to block the analgesic action of meperidine in the hot-plate test was also assessed. The ability of meperidine to fit into the alpha(2B) adrenoceptor was assessed using molecular modeling techniques. RESULTS: Meperidine bound to all alpha2-adrenoceptor subtypes, with alpha(2B) having the highest affinity (alpha(2B), 8.6 +/- 0.3 microm; alpha(2C), 13.6 +/- 1.5 microm, P < 0.05; alpha(2A), 38.6 +/- 0.7 microm). Morphine was ineffective at binding to any of the receptor subtypes. Meperidine inhibited the production of forskolin-stimulated cyclic adenosine monophosphate mediated by all receptor subtypes but was most effective at the alpha(2B) adrenoceptor (alpha(2B), 0.6 microm; alpha(2A), 1.3 mm; alpha(2C), 0.3 mm), reaching the same level of inhibition (approximately 70%) as achieved with the alpha2-adrenoceptor agonist dexmedetomidine. The analgesic action of meperidine was blocked by naloxone but not by the alpha 2-adrenoceptor antagonists yohimbine and RX821002. The modeling studies demonstrated that meperidine can fit into the alpha(2B)-adrenoceptor subtype. CONCLUSION: Meperidine is a potent agonist at the alpha2 adrenoceptors at its clinically relevant concentrations, especially at the alpha(2B)-adrenoceptor subtype. Activation of the alpha(2B) receptor does not contribute significantly to the analgesic action of meperidine. This raises the possibility that some of its actions, such as antishivering, are transduced by this mechanism.

Adenylyl Cyclase Inhibitors↗

HIV-1 prevalence, HIV-1 subtypes and risk factors among fishermen in the Gulf of Thailand and the Andaman Sea.

OBJECTIVE: Mobile populations are thought to be at high risk for HIV-1 infection. This study aims to determine the prevalence of HIV-1 infection, HIV-1 subtypes and socio-demographic and behavioural risk factors among fishermen in the Gulf of Thailand and the Andaman Sea. METHODS: A cross-sectional survey, consisting of face-to-face interviews and the collection of oral fluid samples, was conducted in Samut Sakorn, Ranong, Songkhla and Traat Provinces, Thailand, between January and April 1998. Oral fluid samples were double-tested for HIV-1 antibody by IgG antibody capture enzyme-linked immunosorbent assay and enzyme immunoassay, and confirmed by Western blot. The presence of subtypes B' and E was assessed using a peptide enzyme immunoassay. RESULTS: Of the 818 fishermen (582 Thai, 137 Burmese, 99 Khmer) 15.5% were HIV-1 positive: 14.6% among Thai, 16.1% among Burmese and 20.2% among Khmer. Of the 119 HIV-1 positive samples available for subtyping, 72 (61%) were subtype E, 15 (13%) were subtype B'; the subtype could not be determined for 32 (27%) samples. Sixteen per cent of subjects had ever visited a commercial sex worker outside Thailand. This behaviour was more prevalent among Khmer (40%) than among Thai and Burmese (12%). In univariate logistic regression analysis, being 25 to 32 years of age, compared with being older or younger; working as a fisherman between 4 and 10 years, compared with working for a shorter or longer period; being unmarried; being a steersman or mechanic, compared with being a skipper or ship hand; greater number of visits to commercial sex workers; having visited a commercial sex worker outside Thailand; alcohol or drug use before or during sex; being tattooed; and having a history of sexually transmitted disease were significantly related to prevalent HIV-1 infection. Male-to-male sex and injection drug use were rarely reported in this population. In multivariate analysis, being 25 to 32 years of age, being unmarried, having a tattoo and a greater number of visits to commercial sex workers remained in the model to predict HIV-1 prevalence. A history of drug injection was predictive for infection with HIV-1 subtype B'. CONCLUSIONS: These findings indicate a high HIV-1 prevalence among fishermen in the Gulf of Thailand and the Andaman Sea. Risk factor analysis suggests that heterosexual intercourse is the major mode of transmission in this population. Increased efforts to reduce the spread of HIV-1 among this epidemiologically important group are urgently needed.

Adult↗

Subtypes of aggression and their relevance to child psychiatry.

OBJECTIVE: To review the evidence for qualitatively distinct subtypes of human aggression as they relate to childhood psychopathology. METHOD: Critical review of the pertinent literature. RESULTS: In humans, as well as in animals, the term aggression encompasses a variety of behaviors that are heterogeneous for clinical phenomenology and neurobiological features. No simple extrapolation of animal subtypes to humans is possible, mainly because of the impact of complex cultural variables on behavior. On the whole, research into subtypes of human aggression has been rather limited. A significant part of it has been conducted in children. Clinical observation, experimental paradigms in the laboratory, and cluster/factor-analytic statistics have all been used in an attempt to subdivide aggression. A consistent dichotomy can be identified between an impulsive-reactive-hostile-affective subtype and a controlled-proactive-instrumental-predatory subtype. Although good internal consistency and partial descriptive validity have been shown, these constructs still need full external validation, especially regarding their predicting power of comorbidity, treatment response, and long-term prognosis. CONCLUSIONS: Our understanding and treatment of children and adolescents with aggressive behavior can benefit from research on subtypes of aggression. The differentiation between the impulsive-affective and controlled-predatory subtype as qualitatively different forms of aggressive behavior has emerged as the most promising construct. Specific therapeutic hypotheses could be tested in this context and contribute to a full validation of these concepts.

Adolescent↗

Tissue- and subtype-specific modulation of angiotensin II receptors by chronic treatment with cyclosporin A, angiotensin-converting enzyme inhibitors and AT1 antagonists.

We wished to determine whether chronic treatment of rats with cyclosporin A (CSA), an angiotensin-converting enzyme inhibitor (ACEI) or angiotensin receptor antagonists modulates the angiotensin receptor density. In rats treated chronically with CSA, the vasoconstrictor response to angiotensin II (AII) is increased and this increase is modulated by ACEI and angiotensin receptor antagonists. Rats were treated for 6 weeks orally with CSA (15 mg/kg/day), the ACE inhibitor lisinopril (10 mg/kg/day), the angiotensin receptor antagonists DUP 753 (10 mg/kg/day), and D 8731 (10 mg/kg/day) and the combinations CSA + lisinopril, CSA + DUP 753, and CSA + D 8731. Olive oil was used as a control. The number of total AII receptors (Bmax) was determined by Scatchard analysis of [125I]Sar1 Ile8 AII binding in kidney, liver, adrenal cortex, and adrenal medulla. The receptor subtypes were analyzed with the specific antagonists DUP 753 (subtype 1) and PD 123319 (subtype 2). CSA upregulated angiotensin receptors in all organs studied. Lisinopril alone downregulated angiotensin receptors and abolished the effect of CSA in liver and adrenal cortex and medulla, but not in the kidney, where it had no effect. DUP 753 alone downregulated the angiotensin receptor subtype 1 in kidney, liver and adrenal cortex; its effect on the adrenal medulla in which 89% of angiotensin receptors are subtype 2, did not quite reach significance. The combination of DUP 753 and cyclosporin CSA abolished the CSA-induced increase in angiotensin receptor density in all four organs. The angiotensin receptor antagonists D 8731 downregulated the angiotensin receptors (subtype 1) in liver and kidney and upregulated angiotensin receptors (subtype 2) in the adrenal medulla.(ABSTRACT TRUNCATED AT 250 WORDS)

Administration, Oral↗

Prevalence of dry eye subtypes in clinical optometry practice.

BACKGROUND: Dry eye conditions are now recognized as having multiple causes. A subtype-based dry eye diagnostic protocol was developed to determine the prevalence of dry eye and dry eye subtypes, and the effects of age and gender, in subjects presenting to clinical optometry practice. METHODS: Dry eye diagnostic criteria were: presence of one or more McMonnies dry eye survey primary symptoms, fluorescein tear break time < 10 s and rose bengal ocular surface staining. Dry eye subtype differential diagnosis was made predominantly on the basis of biomicroscopic signs. Subtype categories were: lipid anomaly dry eye (LADE), aqueous tear deficiency (ATD), primary mucin anomalies, allergic/toxic dry eye (ADE), primary epitheliopathies and lid surfacing/blinking anomalies (LSADE). RESULTS: Dry eye prevalence was 10.8% for n = 1584 subjects. Dry eye was significantly more prevalent in subjects 40 years or older (18.1%) compared with those < 40 years (7.3%) (p = 0.001). LADE was the most prevalent subtype (4.0%), followed by ADE at 3.1%, LSADE at 1.8%, and ATD at 1.7%. ATD was the only subtype with a significant gender prevalence difference, being more prevalent in women (p = 0.0023). The prevalence of LADE and ATD were significantly greater in those 40 years or older (p = 0.001 and p = 0.0023 respectively). CONCLUSIONS: The results of this study support a subtype-based approach to dry eye diagnosis and management in clinical practice.

Adolescent↗

Molecular subtyping of Treponema pallidum subspecies pallidum.

BACKGROUND AND OBJECTIVES: Epidemiologic studies on syphilis have been hampered by the fact that strains of Treponema pallidum subspecies pallidum (T. pallidum), the causative agent of this disease, cannot be differentiated by either protein-based or deoxyribonucleic acid-based methods. Syphilis is endemic in many developing countries and is common in some industrialized nations. In addition, the disease has been shown to increase the risk of infection with the human immunodeficiency virus. GOAL: To develop a molecular subtyping method for T. pallidum. STUDY DESIGN: Two genes exhibiting intrastrain variability were identified as potential targets for strain differentiation: the acidic repeat protein (arp) gene, which contains a variable number of 60 base pair repeats, and a member of the treponema pallidum repeat (tpr) gene family. Polymerase chain reaction amplification and restriction endonuclease digestion of polymerase chain reaction products from laboratory strains and clinical specimens were used to develop a molecular subtyping scheme for T. pallidum. RESULTS: Determining the number of repeats in the arp gene by polymerase chain reaction resulted in 12 different subtypes among the 63 isolates that were studied. Among those, most (54.2%) had arp genes with 14 repeats. The other 11 subtypes had arp genes with 7 to 21 repeats, each accounting for 2% to 14% of the isolates. Polymerase chain reaction amplification of a member of the tpr gene family from a subset of 46 isolates followed by digestion of the polymerase chain reaction product with MseI resulted in seven restriction fragment length polymorphism patterns designated a to g. Strains with 14 repeats could be grouped into five restriction fragment length polymorphism subtypes. By combining the two systems we observed 16 subtypes among 46 isolates examined. This typing system is stable, reproducible, and easy to perform. In addition, the use of the ABI Genetic Analyzer for the determination of fragment size and banding patterns makes the results unbiased. CONCLUSION: This is the first molecular subtyping system that distinguishes among clinical isolates of T. pallidum.

Animals↗

Nucleotide sequence and restriction fragment-length polymorphism analysis of human T-cell lymphotropic virus type II (HTLV-II) in southern Europe: evidence for the HTLV-IIa and HTLV-IIb subtypes.

Human T-cell lymphotropic virus type II (HTLV-II) has been subtyped into two major groups, IIa and IIb, according to molecular studies involving env gene sequencing. Subsequently, this retrovirus was further subclassified by examining the long terminal repeat (LTR), the most divergent genomic region. Sequence analysis and restriction fragment-length polymorphism (RFLP) applied to the LTR region identified either four or five groups within the IIa subtype (depending on the restriction enzyme sets used) and six within the IIb subtype. In this study, we analyzed the LTR sequences of 29 samples obtained from HTLV-II-infected individuals living in Spain and Italy, which included 24 injecting drug users (IDUs), three blood donors, and two subjects at risk for HIV/HTLV infection. Sequence analysis and phylogenetic analysis of 720 base pairs of the LTR performed in 10 Spanish samples showed that all of these samples belonged to IIb subtype, with a divergence of 7.5% and 1.66% compared with MoT (IIa) and NRA/G12 (IIb) isolates, respectively. RFLP analysis demonstrated the presence of the IIb 4-subtype restriction pattern in 26 samples, a IIb5-subtype pattern in one Italian IDU, and a IIa0-subtype pattern in two Italian samples (blood donors), according to W.M. Switzer's nomenclature. This is the first report of the presence of IIb5 in Southern Europe and IIa0 among Italian blood donors. RFLP correlated with nucleotide sequence and phylogenetic data obtained in this study, demonstrating the ability of the RFLP method to predict the phylogroup of HTLV-II-infected samples.

Base Sequence↗

CRF06-cpx: a new circulating recombinant form of HIV-1 in West Africa involving subtypes A, G, K, and J.

Phylogenetic analysis of numerous strains of HIV-1 isolated from diverse geographic origins has revealed three distinct groups of HIV-1: groups M, N, and O. Within group M, subtypes, sub-subtypes and circulating recombinant forms (CRFs) exist. Recently, two near-full-length genomes of similar complex mosaic viruses containing fragments of subtypes A, G, I, and J were described in patients from Burkina Faso (BFP-90) and Mali (95ML-84). Here, we report on the characterization of two additional full-length genome sequences with similar mosaic structure in epidemiologically unlinked individuals from Senegal (97SE-1078) and Mali (95ML-127). Phylogenetic and recombinant analysis confirmed that the previously described strains, BFP-90 and 95ML-84, were indeed a new CRF of HIV-1, which we can now designate as CRF06-cpx. This new CRF fits the complex (cpx) designation, because four different subtypes (A, G, K, and J) were involved in the mosaic genome structure. The fragment in the pol gene, which was initially characterized as unknown in the BFP-90 strain and subsequently as subtype I in the 95ML-84 strain, is now, with the recent description of the new K subtype, clearly identified as subtype K. CRF06-cpx circulates in Senegal, Mali, Burkina Faso, Ivory Coast, and Nigeria, although the exact prevalence remains to be determined. Importantly, this new variant has also been documented on other continents (Europe [France] and Australia), showing that these viruses are spreading not only locally but globally.

Africa, Western↗

Expression of the five different somatostatin receptor subtypes in endocrine cells of the pancreas.

Knowledge concerning tissue-specific expression of the five somatostatin receptor subtypes is of great importance in understanding their physiological function. We developed rabbit polyclonal antibodies specific for each human somatostatin receptor subtype and report our results concerning the expression in normal endocrine pancreatic cells. The antibodies were produced by immunizing rabbits with fragments specific for the five cloned somatostatin receptor subtypes. Colocalization of these somatostatin receptors with the four major islet hormones--insulin, glucagon, somatostatin, and pancreatic polypeptide--was studied in normal human endocrine pancreatic cells, using double-immunofluorescence staining. High expression of somatostatin receptor subtypes 1, 3, and 4 was found in all endocrine pancreatic cells. Somatostatin receptor subtype 2 was frequently expressed in alpha and beta cells, whereas expression was low in pancreatic polypeptide cells and intermediate in delta cells. Somatostatin receptor subtype 5 was expressed in most beta and delta cells but almost absent in alpha and pancreatic polypeptide cells. There is a variability in the normal expression of somatostatin receptor subtypes among the different human endocrine pancreatic cells. Knowledge of this expression and the physiological function mediated by these receptors will be valuable in the future when considering treatment of endocrine disorders.

Animals↗

Evolutionary history of HIV-1 subtype B and F infections in Brazil.

OBJECTIVE: To reconstruct the onset date of the HIV-1 B and F epidemics in Brazil based on virus diversification over time. DESIGN: We studied HIV-1 env V3 sequences (210 nt) with a known sampling year isolated from HIV-1 positive patients from Brazil between 1989 and 1997: 101 subtype B sequences and 41 subtype F sequences. METHODS: HIV-1 V3 env sequences were grouped by year of collection and the relationship between the sampling years of HIV-1 sequences and their genetic distance to the reconstructed common ancestor (intra-population divergence) or to other sequences from the same year (intra-population diversity) was examined by using linear regression analysis. RESULTS: Regression analysis of nucleotide distances, revealed a highly significant positive correlation between sampling years of subtype B and F V3 sequences and their intra-population divergence (P < 0.001) or diversity (P < 0.0001). In both subtype populations, the divergence and diversity increased at a rate of 0.5 and 0.9% per year, respectively. Considering these evolutionary rates, we estimate the onset of the subtype B and F HIV-1 epidemics in Brazil during early 1970s and early 1980s, respectively. CONCLUSIONS: The consistent correlation between divergence and diversity of the V3 sequences with their sampling years indicates that the molecular clock is operational in the evolution of the HIV-1 in Brazil's epidemic, and show that subtypes B and F are evolving at a similar rate over time. The dating results suggest a discontinuous introduction of these subtypes in the Brazilian population.

Brazil↗

Effects of norepinephrine on alpha-subtype receptors in the feline pulmonary vascular bed.

OBJECTIVE: To test the hypothesis that norepinephrine induces a pressor response in the pulmonary vascular bed of the cat and identify the alpha-(1)adrenoceptor subtypes involved in the mediation or modulation of these effects. DESIGN: Prospective vehicle controlled study. SETTING: University research laboratory. SUBJECTS: Intact chest preparation, adult mongrel cats. INTERVENTIONS: In separate experiments, the effects of 5-methyl-urapidil, a selective alpha-(1)A-subtype adrenoceptor antagonist, chloroethylclonidine, an alpha-(1)B-subtype and -(1)D-subtype adrenoceptor antagonist, and BMY 7378, the selective alpha-(1)D-subtype adrenoceptor antagonist, were investigated on pulmonary arterial responses to norepinephrine and other agonists in the pulmonary vascular bed of the cat. MEASUREMENTS AND MAIN RESULTS: The systemic pressure and lobar arterial perfusion pressure were continuously monitored, electronically averaged, and permanently recorded. In the feline pulmonary vascular bed of the isolated left lower lobe, norepinephrine induced a dose-dependent vasoconstrictor response that was not significantly altered after administration of BMY 7378. However, the responses to norepinephrine were significantly attenuated following administration of 5-methyl-urapidil and chloroethylclonidine. CONCLUSIONS: The results of the present study suggest that norepinephrine has potent vasopressor activity in the pulmonary vascular bed of the cat and that this response may be mediated or modulated by both alpha-(1)A-subtype and -(1)B-subtype adrenoceptor sensitive pathways.

15-Hydroxy-11 alpha,9 alpha-(epoxymethano)prosta-5↗

Gender differences in ADHD subtype comorbidity.

OBJECTIVE: To examine gender differences in attention-deficit/hyperactivity disorder ("ADHD") symptom comorbidity with "oppositional defiant disorder", "conduct disorder", "separation anxiety disorder", "generalized anxiety disorder", speech therapy, and remedial reading in children. METHOD: From 1994 to 1995, data from a large sample (N = 4,371) of twins and siblings studied in the Australian Twin ADHD Project were obtained by mailed DSM-IV-based questionnaires, investigating patterns of comorbidity in the three subtypes of "ADHD": "inattentive", "hyperactive/impulsive", and "combined". A total of 1,550 questionnaires were returned (87%) over the next 12 to 18 months. RESULTS: Analysis of variance showed significant between-group differences in males and females for inattention and hyperactive/impulsive symptom counts with higher rates of "oppositional defiant disorder" and "conduct disorder" in males, and higher rates of "separation anxiety disorder" in females indicating internalizing disorders are more common in females and externalizing disorders are occurring more often in males. Differences were found between the "ADHD" subtypes and the no ADHD category for all comorbid conditions, for both males and females. Children without ADHD consistently had fewer symptoms, while children with the combined subtype showed consistently more comorbid symptoms indicating a strong relationship between high rates of externalizing symptoms and high rates of internalizing symptoms. Gender differences in speech therapy were significant only for the children without ADHD. The rates of "separation anxiety disorder" were higher in females with the "inattention" subtype and the rate of "generalized anxiety disorder" higher for females with the "combined" subtype, indicating that the subtypes of ADHD were associated with these internalizing disorders in different ways. CONCLUSIONS: Although comorbidity differs among ADHD subtypes, there were no significant gender differences in comorbidity for externalizing disorders. Inattentive girls may present with anxiety. Clinical approaches for both males and females should be sensitive to possible language and reading problems.

Analysis of Variance↗

Histologic subtype and margin of resection predict pattern of recurrence and survival for retroperitoneal liposarcoma.

OBJECTIVE: The aim of this study was to determine the pattern of recurrence and prognostic significance of histologic subtype in a large series of patients with primary retroperitoneal liposarcoma. SUMMARY BACKGROUND DATA: Classification of liposarcoma into subtypes, based on morphologic features and cytogenetic aberrations, is now widely accepted. Previous studies have shown that high histologic grade and incomplete gross resection are the most important prognostic factors for survival in patients with retroperitoneal sarcoma and suggest that patients with liposarcoma have a 3-fold higher risk of local recurrence compared with other histologies. METHODS: A prospective database was used to identify 177 patients with primary retroperitoneal liposarcoma treated between July 1982 and June 2002. Histology at primary presentation was reviewed by a sarcoma pathologist and subtyped into 4 distinct groups according to strict criteria. The influence of clinicopathological factors on local recurrence, distant recurrence, and disease-specific survival was analyzed. RESULTS: Of 177 patients with primary retroperitoneal liposarcoma operated on for curative intent, 99 (56%) presented with well-differentiated, 65 (37%) with dedifferentiated, 9 (5%) with myxoid, and 4 (2%) with round cell morphology. The tumor burden was determined by the sum of the maximum tumor diameters. The median tumor burden was 26 cm (5-139). Median follow-up time for 92 (52%) surviving patients was 37 (mean, 0.5-192) months. Multivariate analysis showed that dedifferentiated liposarcoma subtype was associated with a 6-fold increased risk of death compared with well-differentiated histology (P < 0.0001). In addition to histologic subtype, incomplete resection (P < 0.0001), contiguous organ resection (excluding nephrectomy; P = 0.05), and age (P = 0.03) were important independent prognostic factors for survival in retroperitoneal liposarcoma. Retroperitoneal dedifferentiated liposarcoma was associated with an 83% local recurrence rate and 30% distant recurrence rate at 3 years. CONCLUSIONS: The histologic subtype and margin of resection are prognostic for survival in primary retroperitoneal liposarcoma. Dedifferentiated histologic subtype and the need for contiguous organ resection (excluding nephrectomy) was associated with an increase risk of local and distant recurrence. Nephrectomy may be needed to achieve complete resection, but has no measurable influence on disease specific survival.

Databases, Factual↗

Two distinct subtypes of human respiratory syncytial virus.

Antigenic variation of human respiratory syncytial (RS) virus strains was analysed using a collection of nine, six, six, nine and one monoclonal antibodies respectively directed against the large glycoprotein (G), fusion protein (F), matrix protein (M), nucleoprotein (NP) and phosphoprotein (P) components of the Long strain of RS virus. A comparison was made with seven other strains isolated during different years in radioimmune precipitation analyses and immune fluorescence tests. Two different subtypes of the virus were demonstrable. Subtype A included the prototype strains Long and A2 and virus isolates from 1973, 1983 and 1984; subtype B included four virus strains isolated in successive years from 1979 to 1982. Subtype A viruses reacted with all the antibodies, whereas subtype B viruses showed different epitope characteristics in four structural components. The number of altered epitopes were 5/6, 1/2, 2/6 and 1/6 in the G, F, M and NP components, respectively. It is concluded that the two subtypes have evolved separately. The finding of two subtypes may explain previously observed strain variations in neutralization tests, and gives a new perspective on the immunobiology of RS virus.

Antibodies, Monoclonal↗