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PubMed1997

Comparative alpha-1 adrenoceptor subtype selectivity and functional uroselectivity of alpha-1 adrenoceptor antagonists.

We investigated the relevance of selectivity for a given alpha-1-adrenoceptor subtype for in vivo uroselectivity of several alpha-1-adrenoceptor antagonists (alfuzosin, doxazosin, prazosin, tamsulosin, terazosin and 5-Me-urapidil). Comparison of the affinities of these alpha-1-adrenoceptor antagonists at the cloned alpha-1a, alpha-1b and alpha-1d-adrenoceptor subtypes revealed that tamsulosin and 5-Me-urapidil showed selectivity for the alpha-1a subtype. No significant correlations were found between the affinities for alpha-1b or alpha-1d-adrenoceptors and the pK(B) values obtained against phenylephrine-induced contraction of the rabbit prostate in vitro. In contrast, the antagonist potencies in rabbit prostate were correlated (r = 0.89, P < .05) with the pKi values for the alpha-1a-adrenoceptor subtype. However, the pK(B) values were consistently smaller (by 0.6 to 1.9 log unit) than the pKi values for the alpha-1a-adrenoceptor subtype, a result that suggests that the alpha-1-adrenoceptor mediating urethral contractions does not have all the characteristics of the alpha-1a-adrenoceptor. The simultaneous measurement of urethral and arterial pressures in the same conscious male rat allows evaluation of the functional uroselectivity of these antagonists based on their respective effects on both pressures. Dose ranges were selected according to effects on urethral pressure and most antagonists were found effective within the 3 to 100 microg/kg i.v. range. Alfuzosin markedly decreased urethral pressure and either did not decrease blood pressure (10-30 microg/kg) or slightly decreased it at the highest dose tested (100 microg/kg). Doxazosin did not produce sustained reductions in urethral pressure until a dose of 30 microg/kg. Blood pressure was not reduced until 100 microg/kg. Prazosin reduced urethral pressure and blood pressure within the same dose-range whereas terazosin did not decrease urethral pressure at doses that significantly decreased blood pressure (30 and 100 microg/kg). 5-Me-urapidil, an alpha-1a-selective compound did not significantly modify urethral and blood pressure whereas tamsulosin, another alpha-1a-selective compound reduced urethral pressure and blood pressure within the same dose range. In conclusion, in the conscious male rat the functional uroselectivity is not correlated with a selective affinity for the alpha-1a-adrenoceptor subtype.

Adrenergic alpha-1 Receptor Antagonists↗

PubMed1997

Prevalence of subtypes of low back pain in a defined population.

BACKGROUND: For two generations, some back care specialists have emphasized that clinical low back pain is composed of a number of specific syndromes, such as sacroiliitis or trigger points, but the prevalence of these syndromes outside of specialized clinics remains unknown. The purpose of this study was to describe the prevalence of subtypes of low back pain in a defined population. METHODS: The setting was a group model HMO with a population of 54,000. We used a formal group process involving clinicians from many disciplines, long interviews, critical appraisal of the literature, case discussions, and clinical audits to define a set of subtypes of low back pain. Trained physical therapists assessed subtypes in all patients referred for low back pain over a 9-month period, from July 1992 to April 1993. RESULTS: Of the 213 patients evaluated for low back pain, 72% had acute pain (< 3 months) and only 15% had work-related injury. After classification into subtypes, 32% had acute low back strain, 28% had radicular syndromes, 14% had chronic back strain, 10% had sacroiliac syndromes, 6% had posterior facet syndrome, and the remaining 10% included 12 different syndromes. Only about 10% had more than one clinical syndrome. CONCLUSIONS: A limited number of subtypes of low back pain make up the vast majority of low back pain seen in the population at large. Attention to subtypes may provide a way to improve primary care management of low back pain.

Adolescent↗

PubMed1996

[Study on the distribution HIV-1 C subtype in Ruili and other counties, Yunnan, China].

Cooperating with CDC, USA, the Center for AIDS Surveillance, Chinese Academy of Preventive Medicine, first identified the epidemic of HIV-1 C subtype virus in China in 1994. As part of the Eighth-Five National Scientific Program and to get information about the geographical distribution of C subtype of HIV-1 and its epidemic time span in Yunnan, using specific peptide ELISA, we tested 192 anti-HIV-1 positive serums, among intravenous drug users. The results indicated that C subtype of HIV-1 started to appear in Ruili (5.1%) in 1992, and the rates were 12.9% in Ruili and 30.4% in Longchuan in 1993, up to 31.9% in Ruili and 33.3% in Longchuan in 1994. The porpotion of C subtype is increasing among the drug users by year. Whether C subtype would become the main the main epidemic subtype in this areas remains to be under observation.

China↗

PubMed1998

The role of an alpha subtype M2-M3 His in regulating inhibition of GABAA receptor current by zinc and other divalent cations.

Sensitivity of GABAA receptors (GABARs) to inhibition by zinc and other divalent cations is influenced by the alpha subunit subtype composition of the receptor. For example, alpha6beta3gamma2L receptors are more sensitive to inhibition by zinc than alpha1beta3gamma2L receptors. We examined the role of a His residue located in the M2-M3 extracellular domain (rat alpha6 H273) in the enhanced zinc sensitivity conferred by the alpha6 subtype. The alpha1 subtype contains an Asn (N274) residue in the equivalent location. GABA-activated whole-cell currents were obtained from L929 fibroblasts after transient transfection with expression vectors containing GABAA receptor cDNAs. Mutation of alpha1 (alpha1(N274H)) or alpha6 (alpha6(H273N)) subtypes did not alter the GABA EC50 of alphabeta3gamma2L receptors. alpha1(N274H)beta3gamma2L receptor currents were as sensitive to zinc as alpha6beta3gamma2L receptor currents, although alpha6(H273N)beta3gamma2L receptor currents had the reduced zinc sensitivity of alpha1beta3gamma2L receptor currents. We also examined the activity of other inhibitory divalent cations with varying alpha subtype dependence: nickel, cadmium, and copper. alpha6beta3gamma2L receptor currents were more sensitive to nickel, equally sensitive to cadmium, and less sensitive to copper than alpha1beta3gamma2L receptor currents. Studies with alpha1 and alpha6 chimeric subunits indicated that the structural dependencies of the activity of some of these cations were different from zinc. Compared with alpha6beta3gamma2L receptor currents, alpha6(H273N)beta3gamma2L receptor currents had reduced sensitivity to cadmium and nickel, but the sensitivity to copper was unchanged. Compared with alpha1beta3gamma2L receptor currents, alpha1(N274H)beta3gamma2L receptor currents had increased sensitivity to nickel, but the sensitivity to cadmium and copper was unchanged. These findings indicate that H273 of the alpha6 subtype plays an important role in determining the sensitivity of recombinant GABARs to the divalent cations zinc, cadmium, and nickel, but not to copper. Our results also suggest that the extracellular N-terminal domain of the alpha1 subunit contributes to a regulatory site(s) for divalent cations, conferring high sensitivity to inhibition by copper and cadmium.

Amino Acid Sequence↗

PubMed1998

GABAA receptor pharmacology and subtype mRNA expression in human neuronal NT2-N cells.

Human NT2 teratocarcinoma cells differentiate into neuron-like NT2-N cells when treated with retinoic acid. GABA evoked concentration-dependent whole-cell currents in NT2-N cells with an EC50 of 21.8 microM and a Hill slope of 1.2. GABAA receptor (GABAR) currents reversed at ECl- and did not display voltage-dependent rectification. GABAR single channels opened in bursts to a 23 pS main conductance level and a 19 pS subconductance level, with infrequent openings to a 27 pS conductance level. Kinetic properties of the main conductance level were similar to other native and recombinant GABAR channels. Diazepam and zolpidem enhanced GABAR currents with moderate affinity, whereas methyl-6, 7-dimethoxy-4-ethyl-beta-carboline-3-carboxylate inhibited GABAR currents. Loreclezole enhanced GABAR currents with high affinity, but furosemide antagonized GABAR currents with low affinity. The neurosteroids alphaxalone and pregnenolone sulfate appropriately modulated GABAR currents. Zinc blocked GABAR currents with low affinity, but lanthanum did not significantly alter NT2-N GABAR currents. Reverse transcription PCR (RT-PCR) performed on RNA from NT2-N cells clearly detected transcripts encoding human alpha2, alpha3, alpha5, beta3, gamma3, and pi subtypes. The combined pharmacological and RT-PCR results are most consistent with a single or predominant GABAR isoform composed of an alpha2 and/or alpha3 subtype combined with the beta3 and gamma3 subtypes. The data do not rule out receptors containing combinations of alpha2 and/or alpha3 subtypes with the alpha5 subtype or receptors with both beta1 and beta3 subtypes. The presence or absence or the pi subunit in functionally expressed receptors could not be determined.

Anticonvulsants↗

PubMed1998

Patterns of messenger RNA expression for alpha1-adrenoceptor subtypes in human corpus cavernosum.

PURPOSE: The present study evaluated the expression of alpha1-adrenoceptor subtypes in human corpus cavernosum. MATERIALS AND METHODS: The mRNA encoding alpha1a, alpha1b and alpha1d subtypes were assessed by RNA-directed complementary cDNA synthesis followed by Taq DNA amplification. The level of alpha1 mRNA was calculated in arbitrary optical density units and normalized with respect to the length of the respective cDNA fragments. RESULTS: We found that alpha1a, alpha1b and alpha1d adrenoceptor subtypes are expressed in human corpus cavernosum, with a predominant expression of the alpha1a subtype. CONCLUSION: These results suggest that alpha1a-adrenoceptor subtype is important and that understanding the biochemical and functional characteristics of this subtype may lead to the development of specific antagonists in the treatment of impotence.

Actins↗

PubMed1998

Dopamine receptor subtypes expressed in vertebrate (carp and eel) retinae: cloning, sequencing and comparison of five D1-like and three D2-like receptors.

Eight dopamine receptor-like cDNA clones were isolated from the carp (Cyprinus carpio) retina and four dopamine receptor-like cDNA clones were isolated from the European eel (Anguilla anguilla) retina. These cDNA clones show high sequence and structural homology to the known dopamine receptor subtypes. The sequence similarity and phylogenetic analysis revealed that five subtypes (D1A3, D1A4, D1B, D1C and D1X) in the carp retina and four subtypes (D1A1, D1A2, D1B and D1C) in the eel retina are D1-like receptor subtypes, and three (D2, D4A and D4B) in the carp retina are D2-like receptor subtypes; no D2-like receptor was found in the eel. Carp D1A3 and D1A4, carp D4A and D4B, and eel D1A1 and D1A2 are highly homologous pairs of receptors which show significant, domain-specific differences to each other and to their species homologues. The structure of the third cytoplasmic loop in the carp D1X receptor was particularly different from the other D1-like receptors. The implications of these structural differences in terms of dopamine receptor activation and signalling are discussed. It is suggested that the known diverse physiological and pharmacological effects of dopamine on the retinal neurones are likely to be mediated through these multiple receptor subtypes which may be coupled to different signal transduction pathways.

Amino Acid Sequence↗

PubMed1998

Implication of molecular analysis of HLA-A*02 subtyping for unrelated bone-marrow donor selection.

The HLA-A*02 allele is the most heterogeneous allele at HLA-A locus with 22 different subtypes so far identified. All of these subtype polymorphisms are located in alpha 1 and alpha 2 domains which are responsible for peptide biding and HLA restricted recognition by T-cell receptor. The aim of the present study was to determine the frequency of different HLA-A*02 alleles in 33 healthy unrelated Croatians. HLA-A*02 subtyping has also been retrospectively performed in 2 recipient-unrelated donor pairs and in 4 recipient-HLA phenotypically identical parent pairs. All subjects, previously typed as HLA-A2 by serology were tested using HLA-A*02 ARMS-PCR kit which discriminates 17 different A*02 alleles. Among 17 A*02 alleles we have found 4 different A*02 subtypes in healthy unrelated Croatians. The most frequent A*02 allele was A*0201 (84%). The frequency of the remaining A*02 alleles were as follows: A*0205 (3%), A*0207 (6%) and A*0213 (6%). Among 6 tested bone-marrow transplantation (BMT) pairs, only one has been found to be A*02 subtype incompatible (A*0201/A*0205). Four different A*02 alleles are found in Croatian population with the predominance of A*0201. However these results suggest that A*02 subtyping is also necessary for optimal matching of HLA-A*02 positive donor-recipient pairs in HLA incompatible BMT.

Alleles↗

PubMed1976

[Epidemiolgical significance of HBs-antigen subtypes D and Y in the Heidelberg area].

The HGsantigen subtypes D and Y were determined radioimmunologically in 220 HGsAg-positive patients from the Heidelberg area. The subtype D was significantly more frequent (D = 68%) in patients with chronic liver diseases (n = 45) and in healthy HGsAg carriers (n = 32) than in patients with acute viral hepatitis B (n = 143, D = 41%). The subtype distribution in patients with acute viral hepatitis was not constant in the years 1970--1974. An antigen drift from subtype D to subtype Y was shown in healthy HBsAg carriers from 1971 to 1974. The differing distribution of subtypes in persons with transient and persistent HGsAg finding can be explained unequivocally by the altered epidemiological situation at the time of the infection.

Acute Disease↗

PubMed1992

[The laboratory epidemiological study of the joint circulation of the influenza virus A subtypes A/H1N1/ and A/H3N2/ in Bulgaria].

The National Influenza Center of Bulgaria made the epidemiological analysis of the spread of influenza virus, type A, for the period of 11 years on the basis of mass laboratory investigations. Subtype A (H1N1) was found to be the main factor of epidemics in 1978 and 1982, while the epidemics of 1980, 1983, 1985, 1986, 1987 and 1988 were mainly caused by subtype A (H3N2). The data of laboratory and epidemiological studies indicated that after 20-year absence influenza virus A, subtype A (H1N1), was found again to circulate among the population of Bulgaria, and in 1978-1988 circulated simultaneously with the previous subtype A (H3N2). The simultaneous circulation of two subtypes of influenza virus was of great importance for the frequency, spread and duration of influenza epidemics.

Bulgaria↗

PubMed2000

Localization of prostaglandin E receptor subtypes in the ciliary body of mouse eye.

Prostaglandin E2 (PGE2) markedly reduces intraocular pressure (IOP) when applied topically and induces strong relaxation of pre-contracted isolated ciliary muscle through PGE2 receptor. Because the ciliary muscle relaxation reduces IOP by enhancing uveoscleral aqueous outflow, the ciliary muscle where the existence of PGE2 receptors has been demonstrated is thought to be one of the target tissues for PGE2-induced IOP reduction. To investigate the subtypes of PGE2 receptors in the ciliary muscle, the regional distribution of four PGE2 receptor subtypes (EP1, EP2, EP3 and EP4) in the mouse ciliary body was investigated by in situ hybridization using specific probes. Consistent messenger RNA signals for EP1 and EP4 receptors were expressed in the ciliary muscle, although signal levels for these subtypes were less potent as compared with the kidney, which was used as a reference organ. EP2 and EP3 signals were not detected. Stimulation of the EP4 receptor activates adenylate cyclase, which should induce ciliary muscle relaxation. Therefore, the IOP reduction induced by PGE2 analogs may be mediated by the EP4 receptor. In contrast, stimulation of the EP1 receptor is believed to promote intracellular Ca2+ mobilization, and hence should cause ciliary muscle contraction. Thus, the coexistence of EP1 and EP4 receptors in the ciliary muscle suggests that the regulation of ciliary muscle tone by PGE2 is based on a complex mechanism involving multiple receptor subtypes.

Animals↗

PubMed1989

Two distinct subtypes of the HLA-DRw12 haplotypes in the Japanese population detected by nucleotide sequence analysis and oligonucleotide genotyping.

We determined the DNA sequence of the enzymatically amplified second exon of the DRB1 gene of the Drw12 haplotypes derived from three Japanese donors and found two distinct subtypes of the DRw12 haplotype. The two subtypes, designated DRw12a and DRw12b, had single-base substitutions that predicted one amino acid change at residue number 67. The sequence of the DRw12a and DRw12b subtypes differed from those of the other DR haplotypes, but in the first hypervariable region of the DRB1 gene the sequences were identical to those of the DRw8(Dw8.1) and DRw8(Dw8.3) haplotypes. The DRw12a and DRw12b subtypes were detected in a wide range of Japanese donors by genotyping with sequence-specific oligonucleotide probes synthesized according to the DNA sequences of the two subtypes. Results of this study demonstrated that the DRw12 haplotypes in the Japanese population are genetically diverse, as many other DR haplotypes are.

Asian People↗

PubMed2006

Australian multicentre comparison of subtyping methods for the investigation of Campylobacter infection.

In order to identify subtyping methods able to contribute to the surveillance or investigation of Australian Campylobacter infection, six genotypic and three phenotypic subtyping methods were evaluated on a collection of 84 clinical isolates collected over a 30-month period from one region in Australia. The aim was to compare the logistics of various subtyping methods and examine their ability to assist in finding outbreaks or common sources of sporadic infection. The genotypic subtyping methods used were sequencing of the short variable region of the flaA gene, two methods using restriction fragment length polymorphism (RFLP) of the flaA gene using either DdeI or EcoRI with PstI, automated ribotyping, pulsed field gel electrophoresis and multilocus sequence typing. The phenotypic methods employed included Laboratory of Enteric Pathogens serotyping, Lior biotyping and antibiotic resistotyping. The level of agreement between subtyping results was determined. Phenotypic methods showed little agreement whereas genotypic typing methods showed a high level of agreement. Using the premise that five of the six genotypic typing methods were in agreement 15 genotypic groupings were identified. Sequencing of the short variable region of the flaA gene, RFLP of the flaA gene or automated ribotyping in conjunction with multilocus sequence typing best identified genotypic groupings. An alternative combination of RFLP of the flaA gene followed by ribotyping was equally satisfactory. RFLP of the flaA gene appeared to be suitable as a preliminary typing method based on ease of operation, equipment availability and cost.

Australia↗

PubMed2026

Circadian-rhythm-based dynamics of the secretome in molecular subtypes of pancreatic ductal adenocarcinoma.

BACKGROUND: Pancreatic ductal adenocarcinoma (PDAC) lacks a reliable diagnostic biomarker, largely due to its asymptomatic onset and frequent late-stage detection, resulting in a poor 5-year survival rate. Identifying biomarkers for timely diagnosis is critical. Cancer cells display distinct protein regulation changes that drive disease hallmarks, and characterizing these across PDAC subtypes may provide insights into disease progression. RESEARCH DESIGN AND METHODS: In this study, a label-free quantitative (LFQ) proteomics approach using mass spectrometry (MS) was employed to profile circadian rhythm-regulated proteins in the secretome of PDAC cell lines. RESULTS: LFQ analysis revealed rhythmic protein regulation patterns, reflecting temporal control of biological processes in PDAC. Upregulated pathways included signal transduction, glycolysis, angiogenesis, and protein synthesis, indicating enhanced metabolic and proliferative activity. Downregulated immune pathways suggested potential immune modulation. Comparative analysis revealed subtype-specific patterns: the quasi-mesenchymal subtype exhibited higher levels of metabolic and extracellular matrix (ECM) remodeling proteins, while the classical subtype showed higher levels of ECM-degrading proteins, consistent with known phenotypic differences. CONCLUSION: These findings highlight rhythmically regulated proteins as potential subtype-specific markers in PDAC and provide a basis for future validation studies. Mass spectrometry proteomics data are available via the ProteomeXchange Consortium (PRIDE: PXD054693).

Humans↗

PubMed2026

Shared genetic architecture between ADHD and intelligence varies across ADHD subtypes.

BACKGROUND: Attention-deficit/hyperactivity disorder (ADHD) is a heterogeneous neurodevelopmental condition frequently accompanied by cognitive difficulties. Although previous genetic studies have demonstrated substantial overlap between ADHD and intelligence, most have treated ADHD as a single phenotype. However, whether this shared genetic architecture differs across ADHD subtypes remains unclear. METHODS: We conducted a genome-wide cross-trait analysis integrating large-scale genome-wide association study (GWAS) datasets of overall ADHD, its subtypes-childhood ADHD, persistent ADHD, and late-diagnosed ADHD-and intelligence (total N > 300,000). Genome-wide genetic correlations, polygenic overlap, local genetic correlations, and variant-level associations between ADHD phenotypes and intelligence were evaluated to characterize their shared genetic architecture. Shared variants were identified through cross-trait enrichment analyses and subsequently mapped to genes for functional annotation and gene-set enrichment. Bidirectional associations were evaluated using two-sample Mendelian randomization with sensitivity analyses. Additional GWAS datasets were used to validate the robustness of shared loci by assessing the consistency of effect directions. RESULTS: All ADHD phenotypes showed significant negative genetic correlations with intelligence (rg ranging from -0.3442 to -0.4205). Despite these modest genome-wide correlations, cross-trait analyses revealed substantial genetic overlap, including polygenic overlap, local genetic correlations, and variant-level associations. We identified 184 loci jointly associated with ADHD traits and intelligence, including 64 novel loci, whereas no shared loci were detected for persistent ADHD under the current analysis. Functional annotation revealed biologically distinct enrichment patterns across subtypes: childhood ADHD loci were linked to early neurodevelopmental processes, while late-diagnosed ADHD loci were enriched in synapse-related and neuronal signaling pathways. Mendelian randomization analyses suggested bidirectional associations, with stronger evidence supporting a directional association from intelligence to ADHD risk. Furthermore, these shared loci showed largely consistent effect directions across additional GWAS datasets, providing support for the robustness of the findings. CONCLUSIONS: The shared genetic architecture between ADHD and intelligence varies across ADHD subtypes, highlighting distinct biological pathways underlying cognitive heterogeneity in ADHD. These findings suggest that the relationship between ADHD liability and general cognitive ability is not uniform across ADHD subtypes and may inform future research on risk stratification and early identification in child and adolescent psychiatry.

Humans↗

PubMed2026

Automated Classification of Lymphoma Subtypes From Histopathological Images Using a U-Net Deep Learning Model: Comparative Evaluation Study.

BACKGROUND: Accurate classification and grading of lymphoma subtypes are essential for treatment planning. Traditional diagnostic methods face challenges of subjectivity and inefficiency, highlighting the need for automated solutions based on deep learning techniques. OBJECTIVE: This study aimed to investigate the application of deep learning technology, specifically the U-Net model, in classifying and grading lymphoma subtypes to enhance diagnostic precision and efficiency. METHODS: In this study, the U-Net model was used as the primary tool for image segmentation integrated with attention mechanisms and residual networks for feature extraction and classification. A total of 620 high-quality histopathological images representing 3 major lymphoma subtypes were collected from The Cancer Genome Atlas and the Cancer Imaging Archive. All images underwent standardized preprocessing, including Gaussian filtering for noise reduction, histogram equalization, and normalization. Data augmentation techniques such as rotation, flipping, and scaling were applied to improve the model's generalization capability. The dataset was divided into training (70%), validation (15%), and test (15%) subsets. Five-fold cross-validation was used to assess model robustness. Performance was benchmarked against mainstream convolutional neural network architectures, including fully convolutional network, SegNet, and DeepLabv3+. RESULTS: The U-Net model achieved high segmentation accuracy, effectively delineating lesion regions and improving the quality of input for classification and grading. The incorporation of attention mechanisms further improved the model's ability to extract key features, whereas the residual structure of the residual network enhanced classification accuracy for complex images. In the test set (N=1250), the proposed fusion model achieved an accuracy of 92% (1150/1250), a sensitivity of 91.04% (1138/1250), a specificity of 89.04% (1113/1250), and an F1-score of 90% (1125/1250) for the classification of the 3 lymphoma subtypes, with an area under the receiver operating characteristic curve of 0.95 (95% CI 0.93-0.97). The high sensitivity and specificity of the model indicate strong clinical applicability, particularly as an assistive diagnostic tool. CONCLUSIONS: Deep learning techniques based on the U-Net architecture offer considerable advantages in the automated classification and grading of lymphoma subtypes. The proposed model significantly improved diagnostic accuracy and accelerated pathological evaluation, providing efficient and precise support for clinical decision-making. Future work may focus on enhancing model robustness through integration with advanced algorithms and validating performance across multicenter clinical datasets. The model also holds promise for deployment in digital pathology platforms and artificial intelligence-assisted diagnostic workflows, improving screening efficiency and promoting consistency in pathological classification.

Humans↗

PubMedDate not supplied

Plasma measurement of D-dimer levels for the early diagnosis of ischemic stroke subtypes.

BACKGROUND: Different coagulation abnormalities according to stroke subtypes have been reported. We have assessed the clinical utility of D-dimer, a product of fibrin degradation, in the early diagnosis of stroke subtypes. METHODS: Patients hospitalized after an acute ischemic cerebrovascular event underwent D-dimer assay (STA Liatest D-Dimer) (reference level, <0.50 micro g/mL) on days 1, 6 +/- 1, and 12 +/- 1 and were studied to identify stroke subtypes. RESULTS: We included 126 patients (mean age, 75.5 years) and 63 age-matched control subjects. Stroke subtypes were cardioembolic in 34 patients (27%), atherothrombotic in 34 (27%), lacunar in 31 (25%), and unknown in 27 (21%). At all 3 measurements, D-dimer levels were significantly higher in the cardioembolic group (mean +/- SEM, 2.96 +/- 0.51, 2.58 +/- 0.40, and 3.79 +/- 0.30 micro g/mL, respectively) than in the atherothrombotic (1.34 +/- 0.21, 1.53 +/- 0.26, and 2.91 +/- 0.23 micro g/mL, respectively) (P<.05) and lacunar (0.67 +/- 0.08, 0.72 +/- 0.15, and 0.64 +/- 0.06 micro g/mL, respectively) groups (P<.01). The difference was also significant between the latter 2 groups (P<.01). We found no difference between the lacunar group and controls (0.53 +/- 0.14 micro g/mL). According to day 1 measurements, the optimal cutoff point for predicting cardioembolic stroke was 2.00 micro g/mL, resulting in a specificity of 93.2% and in a sensitivity of 59.3%. For predicting lacunar stroke, the cutoff point was 0.54 micro g/mL, with a specificity of 96.2% and a sensitivity of 61.3%. CONCLUSION: The increasing use of the D-dimer assay in clinical practice could be extended to patients presenting with acute cerebrovascular ischemic events to help predict stroke subtype.

Aged↗

PubMed1976

Another view of schizophrenia subtypes. A report from the international pilot study of schizophrenia.

Schizophrenia subtypes are defined predominantly my manifest symptoms and behavior. This report, based on sign and symptom data from the International Pilot Study of Schizophrenia, addresses three questions: (1) Are traditional subtype diagnoses applied similarly across cultures? (2) Are the various traditional subtypes symptomatically distinguishable from one another? (3) Can cluster analytic techniques define a more distinctive set of schizophrenic subgroups? Present State Examination data were reduced to 27 psychopathologic signs and symptoms. Profile analysis of variance results indicate that each subtype appears similar, regardless of center of origin. However, this is based on a lack of distinguishing features between different subtypes. On the other hand, when a cluster analytic technique was used, it showed one large and three small subgroups, each readilty distinguishable from the others. These subgroups, labeled "usual," "flagrant," "insightful," and "hypochondriacal," are described clinically. If replicated or validated, such subgroups may prove meaningful in future considerations of subdivisions of the schizophrenia syndrome.

Culture↗