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PubMed2000

Inaccuracy of clinical phenotyping parameters for hypertensive nephrosclerosis.

BACKGROUND: Multiple studies suggest that hypertension-induced end-stage renal disease (ESRD) is heritable. Identification of nephropathy susceptibility genes absolutely requires accurate phenotyping, but the clinical hypertensive nephrosclerosis (HN) phenotype is poorly characterized. We hypothesized that many patients with HN as the indicated cause of ESRD on the Health Care Financing Administration (HCFA) 2728 form, fail to satisfy stringent HN phenotyping criteria. METHODS: Since renal biopsy documentation of HN is uncommon, clinical parameters for HN phenotype were applied: family history of hypertension, left ventricular hypertrophy, proteinuria <0.5 g/day, and hypertension preceding renal dysfunction (Schlessinger et al., 1994) or urine protein:creatinine (prot:creat) ratio <2.0 and no evidence of other renal diseases (AASK Trial Group, 1997). RESULTS: ESRD patients (n=607, 73% African American, 25% Caucasian) were enrolled in a study to identify HN susceptibility genes. HN was the most common cause of ESRD according to HCFA 2728 forms (37% prevalence). Phenotyping of randomly selected patients with HN from the total cohort revealed that 4/100 subjects satisfied the Schlessinger criteria, and 28/91 African Americans met AASK criteria for HN. From these figures, the adjusted prevalence of HN was only 1.5-13.5%. Of patients that could not be phenotyped for HN, 14 were misdiagnosed, 14 had urine prot:creat >2.0, and insufficient data were available in the remainder. Four patients underwent renal biopsy, but histology from only one was consistent with HN. If the HN phenotype definitions are revised to exclude 'hypertension preceding renal dysfunction', or proteinuria limits, then 44/100 and 39/91 patients respectively satisfy clinical phenotyping parameters for HN. CONCLUSIONS: (i) We provide the strongest evidence to date that HN is less frequent in an ESRD population than commonly assumed if strict clinical criteria are used; many patients clinically diagnosed with HN may have undetected, treatable renal disease from other causes; (ii) relaxing HN phenotype criteria may erroneously include patients with glomerular diseases and secondary hypertension; (iii) reliance on HCFA 2728 diagnoses will confound identification of HN susceptibility genes; (iv) to attain adequate statistical power for genotype analysis, rigorous HN phenotyping will require screening an extremely large number of patients, which can be reasonably accomplished only in a multi-centre trial design.

Black People↗
PubMed1998

Association of apolipoprotein E phenotype with plasma lipoproteins in African-American and white young adults. The CARDIA Study. Coronary Artery Risk Development in Young Adults.

Apolipoprotein E phenotype (APOE phenotype) has been demonstrated to be a genetic determinant of cardiovascular disease. This atherogenicity may be a reflection of the association of APOE phenotype and plasma lipoprotein concentrations. The Coronary Artery Risk Development in Young Adults (CARDIA) Study affords the opportunity to assess the frequency of apolipoprotein E alleles in population-based samples of African Americans and whites in the United States and to compare the associations of APOE phenotype with lipoprotein and apoprotein concentrations. Data from 3,485 African-American and white men and women between the ages of 25 and 37 years who attended the fourth CARDIA Study examination in 1992-1993 were used in this analysis. African-American men and women had significantly higher frequencies of E2 and E4 phenotype and thus higher frequencies of *epsilon2 and *epsilon4 alleles (p < 0.005). Men and women of both races with APOE4 phenotype generally had higher low density lipoprotein cholesterol, apolipoprotein B, and lipoprotein(a) concentrations and lower high density lipoprotein cholesterol concentration, and individuals with APOE3 phenotype had the lowest triglyceride concentration. Major differences between African Americans and whites were observed in the distribution of APOE phenotypes and *epsilon alleles, but APOE phenotype was associated with similar differences in lipoprotein and apoprotein concentrations in both races. The data suggest that APOE phenotype may be a risk factor for cardiovascular disease in both African Americans and whites because it is associated similarly with an adverse lipoprotein profile.

Adolescent↗
PubMed1994

Acetylation phenotype and cutaneous hypersensitivity to trimethoprim-sulphamethoxazole in HIV-infected patients.

OBJECTIVE: Hypersensitivity to trimethoprim-sulphamethoxazole (TMP-SMX) is more common in patients with HIV infection. In non-infected patients, TMP-SMX hypersensitivity is more common in those with a slow acetylator phenotype. This study was conducted to determine whether the slow acetylation phenotype is associated with an increased risk of hypersensitivity to TMP-SMX in patients with HIV infection. METHODS: Acetylation phenotype was determined in 28 HIV-infected subjects, of whom 16 had prior TMP-SMX hypersensitivity and 12 had received long-term TMP-SMX therapy without hypersensitivity, as well as in 29 healthy controls. Acetylation phenotype was determined by measuring the ratio of two urinary caffeine metabolites, 5-acetylamino-6-amino-3-methyl uracil (AAMU) and 1-methylxanthine (1-MX), after ingestion of a single 200 mg dose of caffeine. RESULTS: Of the 28 HIV-infected subjects, 20 (71%) expressed a slow acetylation phenotype and eight (29%) a fast phenotype. By comparison, of the 29 healthy controls, 15 (52%) expressed a slow phenotype (P = 0.11). Of the 16 HIV-infected subjects with prior TMP-SMX hypersensitivity, 15 (94%) had a slow acetylation phenotype, whereas only five out of 12 (42%) non-hypersensitive subjects had a slow acetylation phenotype (P < 0.01). CONCLUSIONS: A slow acetylation phenotype is a risk factor for hypersensitivity to TMP-SMX in HIV-infected subjects.

Acetylation↗
PubMed2006

Spatio-temporal dynamics of alternative male phenotypes in coho salmon populations in response to ocean environment.

1. The coexistence of alternative reproductive phenotypes will probably be shaped by spatial and temporal variability in the environment. However, the effects of such variability on coexistence and the scale at which it operates are seldom understood. 2. To quantify such effects, we examined spatial and temporal dynamics in the abundance and frequency of alternative phenotypes of male coho salmon, Oncorhynchus kisutch Walbaum, which mature as either large fighters (age-3 'hooknoses') or small sneakers (age-2 'jacks'). Using over 20 years of data on coded-wire tagged fish released from nine Oregon hatcheries, we tested for the effects of ocean environment independent of those due to freshwater rearing. 3. Annual fluctuations of the abundance of jack and hooknose males within populations were correlated strongly by brood year (cohort) but not by return year (breeding group). This occurred independently of significant effects of release practice (i.e. the number of fish released, body size at release and date of release), indicating that a synchronized fluctuation in mortality during the first year at sea was the predominant cause. As a result, the annual frequency of the alternative phenotypes at breeding varied considerably within populations. 4. Spatial patterns in the annual fluctuations of the two phenotypes were similar (i.e. synchronous among populations), except that jacks showed local spatial structure (decreased synchrony with distance) not evident among hooknoses. This suggests that oceanic processes affecting the two phenotypes operate at different spatial scales. Despite effects on salmon abundance, the ocean environment had little influence through its effects on salmon growth on the relative frequencies of the alternative phenotypes within and among populations. 5. The results provide insight into the evolutionary dynamics of alternative phenotypes, including an intragenerational time lag that increases annual variability in phenotype frequencies at breeding (return years) and the significance of local freshwater processes, rather than oceanic processes, on phenotype expression. Freshwater processes, such as juvenile growth, timing of migration and breeding competition, operating at evolutionary and intragenerational time-scales, are probably the predominant forces affecting phenotype frequency.

Aging↗
PubMed1993

Serum IgG and IgG subclass contents in different Gm phenotypes.

Different serum IgG and IgG subclass levels were found among Gm phenotypes of a normal population. One hundred and fifty-seven Caucasian blood donors were investigated for the reciprocal Gm allotypes on IgG subclass loci namely: for IgG1, G1m(f) and G1m(a); for IgG2, G2m(n) and G2m("); and for IgG3, G3m(b) and G3m(g), and subgrouped in the seven most common Gm phenotypes. The frequencies of Gm phenotypes and haplotypes were given, including numbers of the previously little known G2m(n,") heterozygous individuals. Mean serum quantities +/- SD and range of IgG, IgG1, IgG2, IgG3 and IgG4 were given for different Gm phenotypes. The IgG content was significantly lower in the Gm(f,",b/f,",b) phenotype in which the IgG2 levels were also significantly lower, compared with values of the other phenotypes. IgG3 levels were significantly lower in the Gm(a,",g/a,",g) phenotype compared with other phenotypes. These data imply the importance of Gm(f,",b/f,",b) and Gm(a,",g/a,",g) phenotypes causing lower amounts of IgG antibodies. In evaluating IgG subclass deficiency, the range for the low responding Gm(f,",b/f,",b) and Gm(a,",g/a,",g) phenotypes should be considered.

Blood Donors↗
PubMed1982

Phenotypic differences among clinically isolated mucoid Pseudomonas aeruginosa strains.

Mucoid strains of Pseudomonas aeruginosa isolated from patients with cystic fibrosis or urinary tract infections displayed many phenotypic differences. The ratios of D-mannuronosyl to L-guluronosyl moieties of the extracellular alginate-like polysaccharides produced by the 19 strains examined varied from 99 to 0.8; the acetyl content of the polymers varied from 0.38 to 0.02 mol per mole of uronosyl residue. The strains also differed with regard to the stability of the mucoid phenotype. Of 15 isolates from patients with cystic fibrosis, 7 displayed stable mucoid phenotypes; 8 isolates were unstable and reverted to the nonmucoid phenotype at high frequency. The four strains isolated from patients with urinary tract infections were also unstable. Strains from urinary tract infections expressed the mucoid phenotype on six different media, both minimal and complex, whereas cystic fibrosis-associated strains varied widely with regard to medium-dependent expression of the mucoid phenotype. Of 15 cystic fibrosis strains, 5 were mucoid on each of six different media, 4 were mucoid on five media, 1 was mucoid on four media, 4 were mucoid on three media, and 1 yielded mucoid colonies on only one of the six media tested. There was no obvious correlation among polysaccharide structure, stability of the mucoid phenotype, and medium-dependent expression of the mucoid phenotype for any of the 19 strains investigated. These data suggest that although mucoid strains of P. aeruginosa must share some common property related to their ability to colonize their host, this property seems to be unrelated to polysaccharide composition, medium-dependent expression of the mucoid phenotype, or stability of the mucoid phenotype.

Culture Media↗
PubMed2001

Gastric and intestinal phenotypic marker expression in gastric carcinomas and its prognostic significance: immunohistochemical analysis of 136 lesions.

OBJECTIVE: It is well known that both gastric and intestinal phenotypic cell markers are expressed in gastric carcinomas, irrespective of their histologic type. However, the clinicopathologic significance of these expressions has not yet been clarified. METHODS: We analyzed the correlations among gastric and intestinal phenotypic marker expression patterns of the tumor, clinicopathologic findings and the patient's outcome in 136 advanced gastric carcinomas. RESULTS: Phenotypic marker expression was immunohistochemically evaluated using the monoclonal antibodies 45M1 (anti-human gastric mucin; HGM), CLH5 (anti-MUC6), Ccp58 (anti-MUC2) and 56C6 (anti-CD10). All tumors were classified as gastric (G), gastric and intestinal mixed (GI), intestinal (I) or unclassified (UC) phenotype. Of the 136 gastric carcinomas, 50 (36.8%), 56 (41.2%), 21 (15.4%) and 9 (6.6%) were classified as G, GI, I and UC phenotype, respectively. The G-phenotype tumors were associated with a higher rate of undifferentiated-type and infiltrative histology as compared with the I-phenotype tumors (p < 0.05 and p < 0.001, respectively). Furthermore, both univariate and multivariate analysis of survival revealed the G-phenotype tumor to be associated with a significantly poorer outcome than the I-phenotype tumor (p < 0.05). CONCLUSION: Our present results indicate that the gastric and intestinal phenotypic marker expression pattern of tumors, determined by the combination of HGM, MUC6, MUC2 and CD10 expression, is prognostically useful for patients with gastric carcinoma.

Adenocarcinoma↗
PubMed1993

Lipoprotein[a] concentrations and apolipoprotein[a] phenotypes in Caucasians and African Americans. The CARDIA study.

Little is known about racial differences in lipoprotein[a] (Lp[a]) concentrations and apolipoprotein[a] (apo[a]) phenotypes. Lp[a] protein concentrations were determined by a double monoclonal antibody enzyme-linked immunosorbent assay method in 4165 Caucasian and African American men and women from four US communities. Apo[a] phenotypes were determined by polyacrylamide gel electrophoresis and immunoblotting on a random subset of these participants (n = 690). The distribution of Lp[a] protein levels in Caucasians was highly skewed (mean, 6.9 mg/dL; median, 3.7 mg/dL). In contrast, the distribution in African Americans was less skewed (mean, 13.0 mg/dL; median, 11.6 mg/dL), and Lp[a] protein levels were approximately double those in Caucasians within most apo[a] phenotypes. The previously described inverse relationship between apo[a] size and Lp[a] concentration was generally confirmed in Caucasians, but the B phenotype had lower Lp[a] levels than the S1 or S2 phenotype. In African Americans, both the B and S1 phenotypes had lower Lp[a] levels than the S2 phenotype. The frequencies of the apo[a] phenotypes in African Americans differed from those in Caucasians (P < .001) and also differed from the frequencies reported in a Sudanese population (P < .002). African Americans had a lower frequency of the S2 phenotype than Caucasians (8% vs 18%; P < .01) and a higher frequency of S3 (36% vs 25%; P < .01). As compared with the data reported in Sudanese, African Americans also had a higher frequency of the S3 phenotype (36% vs 14%; P < .001) and a lower frequency of S4 (29% vs 44%; P < .01).(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1979

Response of variant hereditary angioedema phenotypes to danazol therapy. Genetic implications.

Hereditary angioedema (HAE), an auto-somal dominant disorder characterized by attacks of episodic edema is associated with decreased functional levels of the C1 esterase inhibitor. Approximately 85% of patients have lowered antigen levels of a normal inhibitor protein. 15% of patients have normal or elevated antigenic levels of functionless protein. We have examined the response to danazol therapy of patients with the variant HAE phenotypes possessing the abnormal protein in an effort to determine if these patients possess a normal structural C1 inhibitor allele. Four patients with a variant HAE phenotype were treated successfully with danazol. In two patients, distinguished by the presence of a functionless, albumin-bound, C1 inhibitor (phenotype 2), phenotypic analysis of the danazol response by bidirectional immunoelectrophoresis revealed the appearance of the normal C1 inhibitor gene product during danazol therapy. This relatively cathodal C1 inhibitor peak appears in conjunction with the development of nearly normal functional activity. All of the functional C1 inhibitory activity which appeared in the phenotype 2 treatment serum was associated with the electrophoretically normal inhibitor. This normal protein could be separated from the functionless inhibitor protein by immunoadsorption and molecular sieve chromatography. Danazol therapy of the two patients with an electrophoretically normal, functionless C1 inhibitor (phenotype 3) also resulted in a clinical remission associated with development of a significant increment in functional serum C1 inhibitory activity and C1 inhibitor protein. These findings demonstrate that these two HAE phenotypic variants are heterozygous for the normal serum C1 inhibitor, a finding which was not apparent before phenotypic analysis of this serum during danazol therapy. These data provide strong evidence for a basic similarity between the common form of HAE and its phenotypic variants. They also suggest that a structural gene lesion may result in the abnormalities of serum C1 inhibitor function and disease expression in all three of these HAE phenotypes.

Angioedema↗
PubMed1991

Phenotypes of apolipoprotein B and apolipoprotein E after liver transplantation.

Apolipoprotein (apo) E and the two B apolipoproteins, apoB48 and apoB100, are important proteins in human lipoprotein metabolism. Commonly occurring polymorphisms in the genes for apoE and apoB result in amino acid substitutions that produce readily detectable phenotypic differences in these proteins. We studied changes in apoE and apoB phenotypes before and after liver transplantation to gain new insights into apolipoprotein physiology. In all 29 patients that we studied, the postoperative serum apoE phenotype of the recipient, as assessed by isoelectric focusing, converted virtually completely to that of the donor, providing evidence that greater than 90% of the apoE in the plasma is synthesized by the liver. In contrast, the cerebrospinal fluid apoE phenotype did not change to the donor's phenotype after liver transplantation, indicating that most of the apoE in CSF cannot be derived from the plasma pool and therefore must be synthesized locally. The apoB100 phenotype (assessed with immunoassays using monoclonal antibody MB19, an antibody that detects a two-allele polymorphism in apoB) invariably converted to the phenotype of the donor. In four normolipidemic patients, we determined the MB19 phenotype of both the apoB100 and apoB48 in the "chylomicron fraction" isolated from plasma 3 h after a fat-rich meal. Interestingly, the apoB100 in the chylomicron fraction invariably had the phenotype of the donor, indicating that the vast majority of the large, triglyceride-rich apoB100-containing lipoproteins that appear in the plasma after a fat-rich meal are actually VLDL of hepatic origin. The MB19 phenotype of the apoB48 in the plasma chylomicron fraction did not change after liver transplantation, indicating that almost all of the apoB48 in plasma chylomicrons is derived from the intestine. These results were consistent with our immunocytochemical studies on intestinal biopsy specimens of organ donors; using apoB-specific monoclonal antibodies, we found evidence for apoB48, but not apoB100, in donor intestinal biopsy specimens.

Adult↗
PubMed2003

Defining clinical phenotypes of juvenile mania.

OBJECTIVE: The authors suggest criteria for a range of narrow to broad phenotypes of bipolar disorder in children, differentiated according to the characteristics of the manic or hypomanic episodes, and present methods for validation of the criteria. METHOD: Relevant literature describing bipolar disorder in both children and adults was reviewed critically, and the input of experts was sought. RESULTS: Areas of controversy include whether the diagnosis of bipolar disorder should require clearly demarcated affective episodes and, if so, of what duration, and whether specific hallmark symptoms of mania should be required for the diagnosis. The authors suggest a phenotypic system of juvenile mania consisting of a narrow phenotype, two intermediate phenotypes, and a broad phenotype. The narrow phenotype is exhibited by patients who meet the full DSM-IV diagnostic criteria for hypomania or mania, including the duration criterion, and also have hallmark symptoms of elevated mood or grandiosity. The intermediate phenotypes include 1) hypomania or mania not otherwise specified, in which the patient has clear episodes and hallmark symptoms, but the episodes are between 1 and 3 days in duration, and 2) irritable hypomania or mania, in which the patient has demarcated episodes with irritable, but not elevated, mood. The broad phenotype is exhibited by patients who have a chronic, nonepisodic illness that does not include the hallmark symptoms of mania but shares with the narrower phenotypes the symptoms of severe irritability and hyperarousal. CONCLUSIONS: The presence of distinct episodes and hallmark symptoms can be used to differentiate clinical phenotypes of juvenile mania. The utility and validity of this system can be tested in subsequent research.

Adolescent↗
PubMed2001

Phenotypic variation in a family with partial androgen insensitivity syndrome explained by differences in 5alpha dihydrotestosterone availability.

Mutations in the androgen receptor (AR) gene result in a wide range of phenotypes of the androgen insensitivity syndrome (AIS). Inter- and intrafamilial differences in the phenotypic expression of identical AR mutations are known, suggesting modifying factors in establishing the phenotype. Two 46,XY siblings with partial AIS sharing the same AR gene mutation, R846H, but showing very different phenotypes are studied. Their parents are first cousins. One sibling with grade 5 AIS was raised as a girl; the other sibling with grade 3 AIS was raised as a boy. In both siblings serum levels of hormones were measured; a sex hormone-binding globulin (SHBG) suppression test was completed; and mutation analysis of the AR gene, Scatchard, and SDS-PAGE analysis of the AR protein was performed. Furthermore, 5alpha-reductase 2 expression and activity in genital skin fibroblasts were investigated, and the 5alpha-reductase 2 gene was sequenced. The decrease in SHBG serum levels in a SHBG suppression test did not suggest differences in androgen sensitivity as the cause of the phenotypic variation. Also, androgen binding characteristics of the AR, AR expression levels, and the phosphorylation pattern of the AR on hormone binding were identical in both siblings. However, 5alpha-reductase 2 activity was normal in genital skin fibroblasts from the phenotypic male patient but undetectable in genital skin fibroblasts from the phenotypic female patient. The lack of 5alpha-reductase 2 activity was due to absent or reduced expression of 5alpha-reductase 2 in genital skin fibroblasts from the phenotypic female patient. Exon and flanking intron sequences of the 5alpha-reductase 2 gene showed no mutations in either sibling. Additional intragenic polymorphic marker analysis gave no evidence for different inherited alleles for the 5alpha-reductase 2 gene in the two siblings. Therefore, the absent or reduced expression of 5alpha-reductase 2 is likely to be additional to the AIS. Distinct phenotypic variation in this family was caused by 5alpha-reductase 2 deficiency, additional to AIS. This 5alpha-reductase deficiency is due to absence of expression of the 5alpha-reductase iso-enzyme 2 as shown by molecular studies. The distinct phenotypic variation in AIS here is explained by differences in the availability of 5alpha-dihydrotestosterone during embryonic sex differentiation.

3-Oxo-5-alpha-Steroid 4-Dehydrogenase↗
PubMed2025

Divergent and stabilizing selection shape the phenotypic space of Arabidopsis thaliana.

Why do we observe some plant phenotypes but not others? The multivariate phenotypic space occupied by individuals or species often reveals both limits and phenotypes strikingly deviating from main syndromes. These observations are usually thought to indicate, respectively, inviable trait combinations and unique phenotypes adapted to specific environments. However, the evolutionary drivers underlying trait covariations often remain unclear. Here, we characterized the phenotypic space of Arabidopsis thaliana by comparing 713 wild accessions collected across the globe with 2,544 artificially-created recombinant individuals. This, combined with the detection of adaptive processes operating within species, allowed us to elucidate the roles of natural selection as a driver of phenotypic (co)variations within A. thaliana. We found that the phenotypic space of this species is constrained and driven by varying levels of divergent and stabilizing selection across different traits. Moreover, at the margins of the European geographic range, strong directional selection favored outlier phenotypes characterized by very late flowering and variation in a WRKY transcription factor gene. Genome analyses revealed that these extreme phenotypes may be explained by hybridization between ancestral and modern lineages of A. thaliana. Our findings demonstrate how interplays between population history and natural selection shape phenotypic diversity in a plant species.

Arabidopsis↗
PubMed2005

Why are phenotypic mutation rates much higher than genotypic mutation rates?

The evolution of genotypic mutation rates has been investigated in numerous theoretical and experimental studies. Mutations, however, occur not only when copying DNA, but also when building the phenotype, especially when translating and transcribing DNA to RNA and protein. Here we study the effect of such phenotypic mutations. We find a maximum phenotypic mutation rate, umax, that is compatible with maintaining a certain function of the organism. This may be called a phenotypic error threshold. In particular, we find a minimum phenotypic mutation rate, umin, with the property that there is (nearly) no selection pressure to reduce the rate of phenotypic mutations below this value. If there is a cost for lowering the phenotypic mutation rate, then umin is close to the optimum phenotypic mutation rate that maximizes the fitness of the organism. In our model, there is selective pressure to decrease the rate of genotypic mutations to zero, but to decrease the rate of phenotypic mutations only to a positive value. Despite its simplicity, our model can explain part of the huge difference between genotypic and phenotypic mutation rates that is observed in nature. The relevant data are summarized.

Animals↗
PubMed2002

ABO, Lewis, secretor and non-secretor phenotypes in patients infected or uninfected by the Helicobacter pylori bacillus.

CONTEXT: Epidemiological studies have demonstrated higher frequencies of the O blood group and the non-secretor phenotype of ABH antigens among patients suffering from peptic ulcers. Since Helicobacter pylori has been established as the main etiological factor in this disease, controversies about the associations of the ABO and Lewis blood group phenotypes and secretor and non-secretor phenotypes in relation to susceptibility towards infection by this bacillus have been presented. OBJECTIVE: To verify the frequencies of ABO, Lewis blood group phenotypes, secretor and non-secretor phenotypes in patients infected or uninfected by H. pylori. DESIGN: Cross-sectional study. SETTING: Outpatient clinic. PARTICIPANTS: One hundred and twenty patients with dyspeptic symptoms who underwent endoscopy. MAIN MEASUREMENTS: ABO and Lewis blood group phenotypes were determined by a standard hemagglutination test and the secretor and non-secretor phenotypes were evaluated by saliva samples using the inhibitor hemagglutination test. RESULTS: The diagnosis of infection, made via breath and urea tests and confirmed using polymerase chain reaction (PCR) in gastric biopsy fragments, showed the presence of H. pylori in 61.7% of the patients and absence in 38.3%. The differences between the frequencies of the ABO blood group phenotypes among infected (A 27.0%; B 12.2%; AB 4.0% and O 56.8%) and uninfected patients (A 58.7%; B 13.0%; AB 4.3% and O 24.0%) were significant. The Lewis blood type, secretor and non-secretor phenotypes showed homogeneous distribution between the groups of patients analyzed. CONCLUSIONS: Our results suggest that the infection of H. pylori can be related to ABO blood groups but not to the Lewis blood group nor to secretor and non-secretor phenotypes.

ABO Blood-Group System↗
PubMed2000

Lipoprotein(a) serum concentrations and apolipoprotein(a) phenotypes in mild and moderate renal failure.

High lipoprotein(a) (Lp(a)) serum concentrations and the underlying apolipoprotein(a) (apo(a)) phenotypes are risk factors for cardiovascular disease in the general population as well as in patients with renal disease. Lp(a) concentrations are markedly elevated in patients with end-stage renal disease. However, nothing is known about the changes of Lp(a) depending on apo(a) size polymorphism in the earliest stages of renal impairment. In this study, GFR was measured by iohexol technique in 227 non-nephrotic patients with different degrees of renal impairment and was then correlated with Lp(a) serum concentrations stratified according to low (LMW) and high (HMW) molecular weight apo(a) phenotypes. Lp(a) increased significantly with decreasing GFR. Such an increase was dependent on apo(a) phenotype. Only renal patients with HMW apo(a) phenotypes expressed higher median Lp(a) concentrations, i.e., 6.2 mg/dl at GFR >90 ml/min per 1.73 m2, 14.2 at GFR 45 to 90 ml/min per 1.73 m2, and 18.0 mg/dl at GFR <45 ml/min per 1.73 m2. These values were markedly different when compared with apo(a) phenotype-matched control subjects who had a median level of 4.4 mg/dl (ANOVA, linear relationship, P < 0.001). In contrast, no significant differences were observed at different stages of renal function in patients with LMW apo(a) phenotypes when compared with phenotype-matched control subjects. The elevation of Lp(a) was independent of the type of primary renal disease and was not related to the concentration of C-reactive protein. Multiple linear regression analysis found that the apo(a) phenotype and GFR were significantly associated with Lp(a) levels. Non-nephrotic-range proteinuria modified the association between GFR and Lp(a) levels. In summary, an increase of Lp(a) concentrations, compared with apo(a) phenotype-matched control subjects, is seen in non-nephrotic patients with primary renal disease even in the earliest stage when GFR is not yet subnormal. This change is found only in subjects with HMW apo(a) phenotypes, however.

Adult↗
PubMed2006

Reciprocal phenotypic plasticity in a predator-prey interaction between larval amphibians.

In biological interactions, phenotypic change in interacting organisms induced by their interaction partners causes a substantial shift in some environmental factor of the partners, which may subsequently change their phenotype in response to that modified environmental factor. Few examples of such arms-race-like plastic responses, known as reciprocal phenotypic plasticity, have been identified in predator-prey interactions. We experimentally identified a reciprocal defensive plastic response of a prey species against a predator with a predaceous phenotype using a model system of close predator-prey interaction. Rana pirica tadpoles (the prey species) were reared with larvae of the salamander Hynobius retardatus (the predator species) having either a predaceous or a typical, nonpredaceous phenotype. The H. retardatus larvae with the predaceous phenotype, which is known to be induced by the presence of R. pirica tadpoles, induced a more defensive phenotype in the tadpoles than did larvae with the typical phenotype. The result suggests that the reciprocal phenotypic plasticity of R. pirica tadpoles is in response to a phenotype-specific signal under a close-signal recognition process.

Adaptation, Physiological↗
PubMed1994

Apolipoprotein A-IV levels and phenotype distribution in NIDDM.

OBJECTIVE: To determine plasma apolipoprotein A-IV (apoA-IV) levels and phenotype distribution in non-insulin-dependent diabetes mellitus (NIDDM) patients and to analyze the influence of apoA-IV phenotype on lipid profiles in NIDDM. RESEARCH DESIGN AND METHODS: Total cholesterol, triglyceride, high-density lipoprotein (HDL) cholesterol, HDL2 cholesterol, HDL3 cholesterol, free fatty acid, and apoA-IV levels were measured in 83 NIDDM patients and 100 normal control subjects. The apoA-IV phenotype was determined in each individual. RESULTS: In both sexes, NIDDM patients had significantly higher levels of triglyceride and free fatty acid and significantly lower levels of HDL cholesterol and HDL2 cholesterol than control subjects. In men and women, apoA-IV levels were significantly higher in diabetic patients than in control subjects (men: 17.1 +/- 7.9 vs. 12.3 +/- 3.6 mg/dl, P < 0.001; women: 18.9 +/- 9.9 vs. 11.9 +/- 3.5 mg/dl, P < 0.001). The multiple regression analysis showed that the apoA-IV level in NIDDM patients was significantly and independently related to log triglyceride (P = 0.0001) and HDL cholesterol (P = 0.01) levels. The apoA-IV phenotype distribution was not significantly different between NIDDM patients and control subjects. In the control subjects, the apoA-IV-1-2 phenotype was associated with significantly higher levels of HDL cholesterol (69 +/- 12 vs. 56 +/- 11 mg/dl, P < 0.01) and of HDL2 cholesterol (36 +/- 15 vs. 25 +/- 12 mg/dl, P < 0.05) compared with the apoA-IV-1-1 phenotype; on the other hand, HDL cholesterol and HDL2 cholesterol levels were not different between the two apoA-IV phenotypes in NIDDM patients. CONCLUSIONS: Plasma apoA-IV levels are increased in NIDDM patients. This increase in apoA-IV is related mainly to hypertriglyceridemia and, to a lesser extent, to HDL cholesterol level. The apoA-IV phenotype distribution is not different between NIDDM patients and nondiabetic control subjects. The potential protective lipid profile (characterized by increased HDL and HDL2 cholesterol levels) linked with apoA-IV-1-2 phenotype in control subjects is no longer found in NIDDM patients. We suggest that the metabolic state of NIDDM has erased the potential protective lipid profile associated with the apoA-IV-1-2 phenotype.

Apolipoproteins A↗