Showing papers by "University of Texas Health Science Center at Houston published in 1992"

Effect of captopril on mortality and morbidity in patients with left ventricular dysfunction after myocardial infarction. results of the survival and ventricular enlargement trial

Abstract: Background. Left ventricular dilatation and dysfunction after myocardial infarction are major predictors of death. In experimental and clinical studies, long-term therapy with the angiotensin-converting—enzyme inhibitor captopril attenuated ventricular dilatation and remodeling. We investigated whether captopril could reduce morbidity and mortality in patients with left ventricular dysfunction after a myocardial infarction. Methods. Within 3 to 16 days after myocardial infarction, 2231 patients with ejection fractions of 40 percent or less but without overt heart failure or symptoms of myocardial ischemia were randomly assigned to receive double-blind treatment with either placebo (1116 patients) or captopril (1115 patients) and were followed for an average of 42 months. Results. Mortality from all causes was significantly reduced in the captopril group (228 deaths, or 20 percent) as compared with the placebo group (275 deaths, or 25 percent); the reduction in risk was 19 percent (95 percent conf...

Information Processing in the Primate Visual System: An Integrated Systems Perspective

Abstract: The primate visual system contains dozens of distinct areas in the cerebral cortex and several major subcortical structures. These subdivisions are extensively interconnected in a distributed hierarchical network that contains several intertwined processing streams. A number of strategies are used for efficient information processing within this hierarchy. These include linear and nonlinear filtering, passage through information bottlenecks, and coordinated use of multiple types of information. In addition, dynamic regulation of information flow within and between visual areas may provide the computational flexibility needed for the visual system to perform a broad spectrum of tasks accurately and at high resolution.

Apolipoprotein(a) gene accounts for greater than 90 % of the variation in plasma lipoprotein(a) concentrations

Abstract: Plasma lipoprotein(a) [Lp(a)], a low density lipoprotein particle with an attached apolipoprotein(a) [apo(a)], varies widely in concentration between individuals. These concentration differences are heritable and inversely related to the number of kringle 4 repeats in the apo(a) gene. To define the genetic determinants of plasma Lp(a) levels, plasma Lp(a) concentrations and apo(a) genotypes were examined in 48 nuclear Caucasian families. Apo(a) genotypes were determined using a newly developed pulsed-field gel electrophoresis method which distinguished 19 different genotypes at the apo(a) locus. The apo(a) gene itself was found to account for virtually all the genetic variability in plasma Lp(a) levels. This conclusion was reached by analyzing plasma Lp(a) levels in siblings who shared zero, one, or two apo(a) genes that were identical by descent (ibd). Siblings with both apo(a) alleles ibd (n = 72) have strikingly similar plasma Lp(a) levels (r = 0.95), whereas those who shared no apo(a) alleles (n = 52), had dissimilar concentrations (r = -0.23). The apo(a) gene was estimated to be responsible for 91% of the variance of plasma Lp(a) concentration. The number of kringle 4 repeats in the apo(a) gene accounted for 69% of the variation, and yet to be defined cis-acting sequences at the apo(a) locus accounted for the remaining 22% of the inter-individual variation in plasma Lp(a) levels. During the course of these studies we observed the de novo generation of a new apo(a) allele, an event that occurred once in 376 meioses.

Prognostic factors influencing survival in gastrointestinal leiomyosarcomas. Implications for surgical management and staging.

Abstract: The appropriate surgical therapeutic options for either localized or more advanced disease in patients with gastrointestinal leiomyosarcomas remain unclear. A staging classification for this disease has not been adopted nor risk factors identifying patients at risk for recurrence defined. To address these issues, this study evaluated the influence of various clinicopathologic variables on overall and disease-free survival. In an univariate analysis of overall survival involving 191 patients, the Cox proportional hazards model identified four factors that were associated with a significantly better outcome: complete resection without tumor rupture (p less than 0.001), localized lesions (p less than 0.001), low grade of tumor (p = 0.02), and tumors smaller than 5 cm (p = 0.03). When interactive effects of these factors were taken into account, however, type of resection of the tumor was selected as the only significant prognostic factor in a multivariate analysis. Complete resection without tumor rupture improved overall survival of patients with localized disease (median, 46 months) as well as those with contiguous organ invasion (median, 36 months) or peritoneal implants (median, 36 months). In contrast, patients with incomplete resections survived for a median of 21 months. Patients with tumor rupture, despite removal of all gross disease, behaved similarly to those with incomplete resections; median survival was only 17 months. For disease-free survival, important determinants selected from a multivariate analysis were tumor rupture (p = 0.002), contiguous organ invasion (p = 0.02) and high tumor grade (p = 0.02). A staging classification incorporating these prognostic factors of significance was evaluated using a TGM system: T1 (less than 5 cm), T2 (greater than or equal to 5 cm), T3 (contiguous organ invasion or peritoneal implants), T4 (tumor rupture); G: G1 (low grade), G2 (high grade); M: M0 (no metastases), M1 (metastases present). The corresponding 5-year overall survivals for stages I, II, III, IVA, and IVB were 75%, 52%, 28%, 12%, and 7%. Disease-free survival at 2 years after surgery was 89%, 57%, and 47% for stages I, II, and III, respectively. In conclusion, surgery remains the primary modality of treatment for patients with gastrointestinal leiomyosarcomas, and complete resection of all disease without tumor rupture, even of locally advanced disease, improves overall and disease-free survival. A staging classification appears feasible and is recommended to determine outcome in patients with leiomyosarcomas arising from the gastrointestinal tract.

Linkage of an important gene locus for tuberous sclerosis to a chromosome 16 marker for polycystic kidney disease.

Abstract: Tuberous sclerosis complex (TSC) is an autosomal dominant disorder of unknown aetiology that affects numerous body systems including skin, brain and kidneys. Some TSC has been linked to chromosome 9, additional TSC genes on chromosomes 11 and 12 have been proposed, but the majority of TSC families remain unlinked. Using TSC families in which data had excluded linkage to chromosome 9, we failed to detect linkage with loci on chromosomes 11, 12 and others. One marker examined was D16S283, the closest locus on the proximal side of the polycystic kidney disease type 1 (PKD1) gene. Linkage between TSC and D16S283 demonstrated a lod score of 9.50 at theta = 0.02 with one family independently presenting a lod score of 4.44 at theta = 0.05. These data reveal an important TSC locus near the region of PKD1 on chromosome 16p13.

Attitudes, Norms, and Self-Efficacy: A Model of Adolescents' HIV-Related Sexual Risk Behavior:

Abstract: Using data from a cross-sectional, statewide survey of 1,720 Texas ninth graders in 13 school districts, a model of psychosocial predictors of human immunodeficiency virus (HIV)-related sexual risk behavior was tested. Predictor variables in the model, based on variables from the Theory of Reasoned Action and Social Learning Theory, were attitudes, norms, self-efficacy, and behavioral intentions. Attitudes, norms, and self-efficacy predicted 36.4% of the variance in the intention to limit the number of sexual partners and the same variables plus intention predicted 24.6% of the variance in number of sexual partners in the past year. Attitudes, norms, and self-efficacy regarding condom use predicted 17.0% of the variance in condom use intentions; these variables plus intentions predicted 19.0% of the variance in condom use frequency. Attitudes, norms, and intentions were directly related to the number of sexual partners, while self-efficacy ad condom use intentions were directly related to frequency of condom use.

Apparent heterozygote deficiencies observed in DNA typing data and their implications in forensic applications.

Abstract: Restriction fragment length polymorphisms (RFLP) analysis using the Southern blot technique can be used to recognize copy number variation of variable number of tandem repeats (VNTR) of conserved core sequences at several regions of the human genome. This new class of polymorphisms reveals a high degree of genetic variation, useful for individual identification purposes. Criticisms against forensic applications of such DNA typing data include the limitation of employing Hardy-Weinberg expectation of genotype frequencies, since several surveys indicate apparent deficiency of heterozygosity (or excess homozygosity) in comparison with Hardy-Weinberg expectations. This research postulates an alternative explanation of deficiency of apparent heterozygosity which is caused by the inability to detect extremely small-sized alleles (called 'non-detectable' alleles) due to the sensitivity of Southern gel electrophoresis. We show that the presence of 'non-detectable' alleles can produce pseudo-homozygosity and their frequencies can be predicted from the observed proportional heterozygote deficiency. Furthermore, in the covert presence of such 'non-detectable' alleles, we show that the gene-count method provides over-estimates of allele frequencies in the sample population, and hence the Hardy-Weinberg predictions of genotype frequencies avoid wrongful bias against suspects in forensic applications of DNA typing data. Applications of this theory to population data on six VNTR loci in US Caucasians and US Blacks suggest that the presence of 'non-detectable' alleles could be the major cause of apparent heterozygote deficiency, and the current approaches of predicting the population frequency of specific DNA phenotypes are practically free of the possible wrongful bias in courtroom applications of DNA typing data.

Grading system for the selection of patients with congenital aural atresia.

Abstract: It is generally recognized that surgery for congenital aural atresia is difficult. In an effort to select those patients who have the greatest chance of success, we have developed a grading scheme based on the preoperative temporal bone CT scan and the appearance of the external ear. Patients are graded on a possible best score of 10. The stapes is assigned the highest rating (2 points), while all other entrees on the scale are 1 point. The grade assigned preoperatively has been shown to correlate well with the patient's chance of success, herein defined as a postoperative speech reception threshold of 15 to 25 dB. A patient with a preoperative grade of 8/10 would, therefore, have a 80 percent chance of achieving this threshold. Patients with scores of 5/10, or less, are not considered surgical candidates, because the risk of the operation would outweigh the potential benefits. We have found that the grading system allows us to avoid impossible surgical cases while allowing for a reasonable prediction of the hearing outcome.

Expression of tissue transglutaminase in Balb-C 3T3 fibroblasts: effects on cellular morphology and adhesion.

Abstract: Tissue transglutaminase is a cytosolic enzyme whose primary function is to catalyze the covalent cross-linking of proteins. To investigate the functions of this enzyme in physiological systems, we have established lines of Balb-C 3T3 fibroblasts stably transfected with a constitutive tissue transglutaminase expression plasmid. Several cell lines expressing high levels of catalytically active tissue transglutaminase have been isolated and characterized. Transglutaminase-transfected cells showed morphologic features quite distinct from their nontransfected counterparts. Many of the cells showed an extended and very flattened morphology that reflected increased adhesion of the cells to the substratum. Other cells, particularly those showing the highest levels of intracellular transglutaminase expression, showed extensive membrane blebbing and cellular fragmentation. The results of these experiments suggest that the induction and activation of tissue transglutaminase may contribute both to changes in cellular morphology and adhesiveness.

Development and initial experimental evaluation of a prosthetic aortic valve for transcatheter placement. Work in progress.

Abstract: A prosthetic caged-ball aortic valve that can be placed with transcatheter techniques was designed, constructed, and initially evaluated in 12 adult mongrel dogs. The prosthesis consisted of a ring, cage, and ball. The ring was made of stainless steel wire coiled in a springlike configuration and covered with an expandable nylon mesh. The cage consisted of a self-expanding Gianturco stent with flat stainless steel wires attached across the cranial end. The ball was a detachable latex balloon filled with a radiopaque silicone prepolymer system. The self-expanding valve was easily passed through an 11- or 12-F Teflon sheath and was placed in the ascending aorta by means of the carotid approach. The stability and efficacy of the prosthesis were evaluated radiographically for as long as the valve remained functional (1-3 hours). The competency of the valve and the patency of the coronary arteries were determined angiographically over the same period. The results of these studies indicate that development and ...

Statistical properties of bootstrap estimation of phylogenetic variability from nucleotide sequences. I. Four taxa with a molecular clock.

Abstract: The statistical properties of sample estimation and bootstrap estimation of phylogenetic variability from a sample of nucleotide sequences were studied by considering model trees of three taxa with an outgroup. The cases of constant and varying rates of nucleotide substitution were compared. From sequences obtained by simulation, phylogenetic trees were constructed by using the maximum parsimony (MP) and neighbor joining (NJ) methods. The effectiveness and consistency of the MP method were studied in terms of proportions of informative sites. The results of simulation showed that bootstrap estimation of the confidence level for an inferred phylogeny can be used even under unequal rates of evolution if the rate differences are not large so that the MP method is not misleading. The condition under which the MP method becomes misleading (inconsistent) is more stringent for slowly evolving sequences than for rapidly evolving ones, and it also depends on the length of the internal branch. If the rate differences are large so that the MP method becomes consistently misleading, then bootstrap estimation will reinforce an erroneous conclusion on topology. Similar conclusions apply to the NJ method with uncorrected distances. The NJ method with corrected distances performs poorly when the sequence length is short but can avoid the inconsistency problem if the sequence length is long and if the distances can be estimated accurately.

Prognostic implications of patterns of failure for gastrointestinal leiomyosarcomas.

Abstract: One hundred ninety-one patients with gastrointestinal leiomyosarcomas were analyzed to determine the prevalence in patterns of failure and the factors predicting those at higher risk of relapse at specific sites. Of 100 assessable patients who died of disease, 89% were found to have peritoneal tumor, 78% had liver metastases, and 32% had extraabdominal metastases. Of 132 patients (69%) with initial complete resection of the primary tumor, only 10% (n = 13) remained free of disease as of the last follow-up. The median interval to recurrence was 18 months; 60% of all recurrences occurred within 2 years after surgery. Half of these patients (n = 61) had metastases (predominantly in the liver) as the initial recurrence. Factors significantly associated with improved survival after relapse were initial disease-free interval of 18 months or more, recurrences either isolated to the peritoneal cavity or within the liver, or complete resection of peritoneal recurrences or liver metastases. In contrast, those patients with recurrences at multiple sites or unresectable disease had significantly shorter survival times. The presence of extraabdominal metastases also heralded an equally poor outcome. In conclusion, a multi-modality approach is necessary to improve outcome from this disease because the liver and peritoneal cavity represent predominant sites of failure. Complete resection of isolated peritoneal or hepatic metastases improves survival and should be attempted when feasible. Cancer 1992; 69:1334-1341.

Meta‐analysis of diabetes patient education research: Variations in intervention effects across studies

Abstract: Data from a previously reported meta-analysis of diabetes patient education literature were reanalyzed to determine the influence of study/subject characteristics, such as study quality and age of subjects, on patient outcomes. Patient knowledge and self-management skills, weight loss, glycosylated hemoglobin levels, and psychological outcomes were analyzed as outcome variables. Seventy-three relevant published and unpublished studies were located. Patient education appeared to be more effective in younger patients, particularly for the knowledge outcome. For all patients, glycosylated hemoglobin levels improved between 1 and 6 months postintervention, but decreased to 1-month levels after 6 months. Length of the educational intervention did not appear to influence outcomes. More rigorous, experimental research designs tended to produce more conservative effect size estimates. Implications for diabetes patient education are discussed.

A comparison of ePTFE membranes alone or in combination with platelet-derived growth factors and insulin-like growth factor-I or demineralized freeze-dried bone in promoting bone formation around immediate extraction socket implants.

Abstract: The purpose of this study was to compare bone promotion around implants which were augmented with ePTFE membranes alone or in combination with cortical demineralized freeze-dried bone (DFDB) or the combination of platelet derived growth factor-BB (PDGF) and insulin like growth factor I (PDGF/IGF-I). Membranes were placed over titanium implants which had been inserted into fresh extraction sockets with large buccal dehiscences. Twenty-four implants were placed in 4 dogs. At 18 weeks clinical bone height measurements were taken, the animals were sacrificed, and all specimens retrieved for histologic evaluation. Clinically, a significant gain in bone levels was present in both the ePTFE membrane alone group (P < 0.005) and PTFE plus PDGF/IGF-I group (P <0.01), but not in the PTFE plus DFDB group. Results from histometric measurements revealed an approximately 2-fold increase in the percentage of implant surface in contact with bone, area of bone adjacent to the implant surface, and in the total length of the...

Identification of intrinsic high-level resistance to rare-earth oxides and oxyanions in members of the class Proteobacteria: characterization of tellurite, selenite, and rhodium sesquioxide reduction in Rhodobacter sphaeroides.

Abstract: We have identified intrinsic high-level resistance (HLR) to tellurite, selenite, and at least 15 other rare-earth oxides and oxyanions in the facultative photoheterotroph Rhodobacter sphaeroides grown either chemoheterotrophically or photoheterotrophically. Other members of the class Proteobacteria, including members of the alpha-2 and alpha-3 phylogenetic subgroups, were also shown to effect the reduction of many of these compounds, although genera from the alpha-1, beta-1, and gamma-3 subgroups did not express HLR to the oxyanions examined. Detailed analyses employing R. sphaeroides have shown that HLR to at least one class of these oxyanions, the tellurite class (e.g., tellurate, tellurite, selenate, selenite, and rhodium sesquioxide), occurred via intracellular oxyanion reduction and resulted in deposition of metal in the cytoplasmic membrane. The concomitant evolution of hydrogen gas from cells grown photoheterotrophically in the presence of these oxyanions was also observed. HLR to tellurite class oxyanions in R. sphaeroides was not affected by exogenous methionine or phosphate but was reduced 40-fold by the addition of cysteine to growth media. In contrast HLR to the periodate class oxyanions (e.g., periodate, siliconate, and siliconite) was inhibited by extracellular PO4(3-) but did not result in metal deposition or gas evolution. Finally, we observed that HLR to arsenate class oxyanions (e.g., arsenate, molybdate, and tungstate) occurred by a third, distinct mechanism, as evidenced by the lack of intracellular metal deposition and hydrogen gas evolution and an insensitivity to extracellular PO4(3-) or cysteine. Examination of a number of R. sphaeroides mutants has determined the obligate requirement for an intact CO2 fixation pathway and the presence of a functional photosynthetic electron transport chain to effect HLR to K2TeO3 under photosynthetic growth conditions, whereas functional cytochromes bc1 and c2 were required under aerobic growth conditions to facilitate HLR. Finally, a purification scheme to recover metals from intact bacterial cells was developed.

Comparison of gastric intramucosal pH with measures of oxygen transport and consumption in critically ill patients.

Abstract: ObjectiveTo determine the relationship of tonometrically measured gastric intramucosal pH to clinically accepted indices of systemic oxygenation.DesignProspective, nonintervention study.SettingMedical and surgical ICUs of a university hospital.PatientsCritically ill patients (n = 22) with pulmonary

Alterations in human enamel surface morphology following vital bleaching

Abstract: Extracted intact human teeth (n = 4) were treated for 30 days by three protocols: Home 1 (Proxigel, n = 4) for 8 hours daily, Home 2 (White & Bright, n = 4) for 24 hours with 3 minutes of stannous fluoride gel, or an Office protocol (n = 4) using 30% hydrogen peroxide (Superoxol) warmed by a high-intensity light while the controls remained untreated. "Home" bleaching agents contain approximately 10% carbamide peroxide. After treatment, the coronal surfaces were examined with a scanning electron microscope (SEM) at 2000 power magnification, and the surface topography was measured by a profilometer. The SEM photomicrographs of the controls and office-treated groups were similar to previously reported descriptions, while the home bleached surfaces appeared similar to each other. Profilometric analysis was used to examine surface roughness and surface waviness. Mean surface roughness in microns was: control, 1.9; Home 1, 0.6; Home 2, 0.9; and Office, 0.6. Surface waviness was ranked control > office > Home 1 = Home 2. Enamel surface alterations were evident after the three bleaching methods. The differences between the office and home-treated surfaces were unrelated to the pH of the bleaching agents.

Multiple myeloma : spinal MR imaging in patients with untreated newly diagnosed disease

Abstract: Spinal magnetic resonance (MR) imaging was performed in 29 patients with newly diagnosed, untreated multiple myeloma. Nineteen (66%) patients were asymptomatic. Sagittal pre- and postcontrast T1-weighted spin-echo images and gradient-recalled-echo images of the thoracic and lumbosacral spine were obtained. Marrow involvement was identified in 20 (69%) patients. There were three MR patterns: focal lesions in nine patients (31%), diffuse involvement in seven (24%), and an inhomogeneous pattern of tiny lesions on a background of normal marrow in four (14%). A statistically significant correlation between MR imaging patterns of marrow involvement and serum hemoglobin values (one-way, P = .0899; Kruskal-Wallis, P = .0620) and between MR imaging patterns and percentage of marrow plasmacytosis (Kruskal-Wallis, P = .0314) was noted, with patterns of diffuse and focal marrow involvement associated with more abnormal values. Spinal MR imaging in patients with early myeloma may reveal marrow involvement in both symptomatic and asymptomatic patients. Some correlation was found between MR imaging patterns and laboratory indexes of disease.

Xeroderma pigmentosum and Cockayne syndrome: overlapping clinical and biochemical phenotypes.

Abstract: Two siblings are described whose clinical presentation of cutaneous photosensitivity and central nervous system dysfunction is strongly reminiscent of the DeSanctis-Cacchione syndrome (DCS) variant of xeroderma pigmentosum. An extensive clinical evaluation supported a diagnosis of DCS and documented previously unreported findings. In vitro fibroblast studies showed UV sensitivity that was two to three times that of normal controls. However, neither a post-UV-irradiation DNA excision-repair defect indicative of XP nor a semiconservative DNA replication defect indicative of XP variant was found. Rather, a failure of RNA synthesis to recover to normal levels after UV exposure was observed, a biochemical abnormality seen in Cockayne syndrome (CS), one of the premature-aging syndromes with clinical UV sensitivity. These patients, therefore, clinically have XP, but their biochemical characteristics suggest CS. The reason(s) for the severe neurologic disease, in light of the relatively mild cutaneous abnormalities, is unclear. Other cases with unusual fibroblast responses to irradiation have been noted in the literature and, along with the data from our patients, reinforce the notion of the complexity of DNA maintenance and repair.

Definition of a tumor suppressor locus within human chromosome 3p21-p22

Abstract: Cytogenetic abnormalities and high-frequency allele losses involving the short arm of human chromosome 3 have been identified in a variety of histologically different neoplasms. These findings suggest that a tumor-suppressor gene or genes may be located in the region of 3p14-p25, although there has been no definitive functional proof for the involvement of a particular region of 3p. We report a rapid genetic assay system that has allowed functional analysis of defined regions of 3p in the suppression of tumorigenicity in vivo. Interspecific microcell hybrids containing fragments of chromosome 3p were constructed and screened for tumorigenicity in athymic nude mice. Hybrid clones were obtained that showed a dramatic tumor suppression and contained a 2-megabase fragment of human chromosomal material encompassing the region 3p21 near the interface with 3p22. With these hybrid clones, we have defined a genetic locus at 3p21-p22 intimately involved in tumor suppression.

Ischemia‐Induced Translocation of Ca2+/Calmodulin‐Dependent Protein Kinase II: Potential Role in Neuronal Damage

Abstract: The activities of Ca2+/calmodulin (CaM)-dependent, Ca2+/phospholipid-dependent, and cyclic AMP-dependent protein kinases (CaM-KII, PKC, and PKA, respectively) were determined in rat brains after global ischemia. Both CaM-KII and PKC activities were significantly depressed in both hippocampal and cerebral cortical regions of ischemic animals, whereas no change was detected in PKA activity. The loss of CaM-KII activity was more dramatic and more sustained than the loss of PKC activity and correlated with the duration of ischemia. These decreases in enzyme activity were found in both supernatant and pellet fractions from crude homogenates. When the supernatant and pellet were analyzed for the amount of CaM-KII 50-kDa protein, a significant decrease was detected in supernatant fractions that paralleled a gain in the amount of CaM-KII in the pellet. Thus, the loss of CaM-KII activity in the supernatant can be explained by translocation of the enzyme to the pellet. Whether inactivation of CaM-KII occurs during or after the enzyme translocates from the supernatant to the pellet is unknown. Our results indicate that loss in CaM-KII activity parallels neuronal damage associated with ischemia; down-regulation of CaM-KII activity coincided with translocation of the enzyme to the particulate fraction, and it is proposed that this may be, in fact, a mechanism for controlling excessive CaM-KII phosphorylation.

Breast cancer screening behaviors and attitudes in three racial/ethnic groups.

Abstract: Data from a multiethnic sample of women participating in the American Cancer Society 1987 Texas Breast Screening Project was used to compare attitudes and behaviors related to breast cancer screening for whites, blacks, and Hispanics. In general, similar patterns of association were observed across racial/ethnic groups between a number of demographic and risk factors and prior mammography and recent clinical breast examination (CBE), although the magnitude of the associations varied somewhat across groups. Reasons for not having had prior mammography also were similar across groups, with lack of physician referral and cost cited as the two most important reasons. However, Hispanics were less likely than blacks or whites to report prior breast cancer screening, including mammography, CBE, and breast self-examination (BSE). This study demonstrated that women of different racial/ethnic backgrounds can be successfully recruited to participate in a patient-initiated, community-based program. However, this programmatic approach requires augmentation with other intervention strategies designed to reach low-income women because women with more years of education and higher family income were overrepresented in all three groups.