Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “phenotypes”

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

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

At least 451 records · Page 25Linked to original sources
PubMed1994

Syncytium-inducing and non-syncytium-inducing capacity of human immunodeficiency virus type 1 subtypes other than B: phenotypic and genotypic characteristics. WHO Network for HIV Isolation and Characterization.

Positively charged amino acid substitutions at positions 11 and 25 within the loop of the third variable region (V3) of HIV-1 subtype B envelope have been shown to be associated with the syncytium-inducing (SI) phenotype of the virus. The present study was designed to examine SI and NSI-associated V3 mutations in HIV-1 subtypes other than B. HIV-1 RNA was isolated from 53 virus stocks and 26 homologous plasma samples from 53 recently infected individuals from Brazil, Rwanda, Thailand, and Uganda. The C2-V3 region of the viral envelope was converted to cDNA, amplified, and sequenced. Of 53 primary virus stock samples 49 were biologically phenotyped through measurement of the syncytium-inducing capacity in MT-2 cells (to differentiate between SI and NSI phenotypes). In addition, after passage of primary isolates through PHA stimulated donor PBMC, the replication capacity was determined in U937-2, CEM, MT-2, and Jurkat-tat cell lines (to differentiate rapid/high and slow/low phenotypes). According to the sequence analysis 9 (17.0%) of the viruses belonged to subtype A, 15 (28.3%) to subtype B, 1 (1.9%) to subtype C, 13 (24.5%) to subtype D, and 15 (28.3%) to subtype E. Sequence analysis of virus RNA, obtained from 26 homologous plasma samples, confirmed the homogeneity of sequence populations in plasma compared to primary virus isolates. Of the 49 viruses tested 12 had the SI phenotype, 5 were confirmed to be rapid/high, and 4 appeared to be slow/low pattern 3 replicating. Of 49, 29 had the NSI phenotype, 24 were confirmed to be slow/low pattern 1 or 2, and 3 appeared to be slow/low pattern 3 replicating. Analysis of mutations at V3 loop amino acid positions 11 and 25 revealed that 10/12 (83.3%) of the SI viruses had SI-associated V3 mutations and that 28/29 (96.6%) of the NSI viruses lacked these mutations. V3 loop heterogeneity, length polymorphism, and a high number of positively charged amino acid substitutions were most frequently found among subtype D variants. These results indicate that both the phenotypic distinction between SI and NSI viruses and the association of biological phenotype with V3 mutations is present among HIV-1 subtypes other than B.

Adult↗
PubMed1996

Apolipoprotein E phenotype modifies metabolic and hemodynamic abnormalities related to central obesity in women.

Apolipoprotein E (apo E) is a normal constituent of very-low-density lipoproteins and it participates in the metabolism of both low-density lipoproteins (LDL) and apo E-containing lipoproteins. In the present study, the aim was to examine to what extent apo E phenotypes modify central obesity-induced changes in serum lipids, insulin, and blood pressure in obese women. Altogether, 143 middle-aged obese women with a body mass index (in kg/m2) of 28.0-43.0 were examined. Twelve had apo E 3,2 phenotype, 93 had apo E 3,3 phenotype, and 38 had either apo E 4,3 or 4,4 (4,3 + 4,4 group) phenotype. Serum total and LDL cholesterol were lower in the apo E 3,2 group than in other groups, but no significant differences were observed in other lipid variables in this regard. Both systolic and diastolic blood pressure measures tended to be lowest in subjects with apo E 3,2 phenotype and highest in those with apo E 4,3 or 4,4 phenotype (P = 0.08-0.15 for trend). When serum lipids, blood pressure, and insulin were analyzed by waist circumference and apo E phenotype group, it became evident that women who had central obesity and the apo E 4 allele had the highest blood pressures, insulin-glucose ratios, and insulin concentrations. These results suggest that apo E phenotype significantly modifies the central obesity-induced changes in metabolic and hemodynamic variables characteristic of insulin resistance.

Adult↗
PubMed2003

Rapid gut transit time and slow fecal isoflavone disappearance phenotype are associated with greater genistein bioavailability in women.

The bioavailability of soybean isoflavones varies widely among individuals due to many factors, including activities of gut microflora. To characterize factors that affect fecal isoflavone disappearance phenotype and isoflavone bioavailability in women, 35 Asian and 33 Caucasian women, 18-43 y of age, provided fecal samples for anaerobic incubation with isoflavones in vitro at two times 5 mo apart (Phases I and II). Diet, physical activity and health history were investigated at these times. A single dose of soymilk powder [1.2 mg (4.57 micromol) total isoflavone/kg body] was given to all subjects with breakfast in phase II. Daidzein and genistein from fecal incubations, urine and fecal samples were measured by reverse-phase HPLC. Three significantly different daidzein and two genistein disappearance phenotypes were identified from fecal isoflavone incubations. More Asians than Caucasians were identified within the high daidzein disappearance phenotype. Caucasians and Asians differed significantly in daily intake of red meat (0.3 +/- 0.1 vs. 1.0 +/- 0.1 servings/d), dairy foods (2.9 +/- 0.2 vs. 1.2 +/- 0.2 servings/d) and insoluble dietary fiber (3.6 +/- 0.3 vs. 1.4 +/- 0.3 g). BMI, maximal oxygen uptake (VO(2 max)) and physical activity level were significantly greater in Caucasians than in Asians. Asian subjects of the low genistein disappearance phenotype had more rapid gut transit time (GTT) and greater isoflavone bioavailability as reflected in urinary genistein excretion than did Asians of the high genistein disappearance phenotype (GTT, 40 +/- 8 vs. 63 +/- 5 h; 11.0 +/- 2.7 vs. 4.0 +/- 1.7% of ingested genistein excreted in urine). Caucasians of both genistein disappearance phenotypes had longer GTT than did Asian subjects (84 +/- 5 vs. 56 +/- 6 h) and resembled Asians of the high genistein disappearance phenotype in genistein bioavailability. Relatively rapid GTT coupled with a low fecal isoflavone disappearance phenotype as occurred in Asian but not Caucasian subjects produced greater genistein bioavailability, as reflected in urinary genistein excretion.

Adolescent↗
PubMed2005

Haptoglobin phenotype, sleep-disordered breathing, and the prevalence of cardiovascular disease: the Sleep Heart Health Study.

BACKGROUND: Diabetes is an independent risk factor for cardiovascular disease, and there is growing evidence that sleep-disordered breathing also may increase the risk of cardiovascular disease. The mechanism responsible for increased susceptibility of people with diabetes to cardiovascular disease is thought to share several features with sleep-disordered breathing, notably increased oxidative stress. We recently demonstrated that a particular haptoglobin phenotype that is associated with differential antioxidant activity is an independent risk factor for cardiovascular disease in individuals with diabetes. We therefore sought to determine whether sleep-disordered breathing and cardiovascular disease are more strongly associated among people with the unfavorable haptoglobin phenotype. METHODS: We tested this hypothesis in 2612 middle-aged and older participants from the Sleep Heart Health Study. Haptoglobin phenotyping was performed by gel electrophoresis. Respiratory disturbance index was assessed by standard methods. Logistic regression analysis was performed to estimate the association between haptoglobin phenotype and cardiovascular disease, adjusting for known cardiovascular risk factors (age, sex, diabetes, smoking, lipid levels, and hypertension). Possible modification by haptoglobin phenotype of the association of sleep-disordered breathing with cardiovascular disease prevalence was explored by examining interaction terms. RESULTS: We found no significant association between haptoglobin phenotype and prevalent cardiovascular disease in this cohort, nor were significant interactions found between haptoglobin phenotype and sleep-disordered breathing on the prevalence of cardiovascular disease. CONCLUSIONS: Sleep-disordered breathing did not appear to interact with haptoglobin phenotype in modifying the association with prevalent cardiovascular disease in the Sleep Heart Health Study. These findings could be due to the absence of association or to survivor bias in these cross-sectional analyses.

Aged↗
PubMed2004

Evidence for development of capillary leak syndrome associated with cardiopulmonary bypass in pediatric patients with the homozygous C4A null phenotype.

BACKGROUND: The mechanism of postoperative capillary leak syndrome related to cardiopulmonary bypass (CPB) is unknown. The authors hypothesized that C4 gene polymorphism might be involved in the development of the syndrome because complement activation is associated with CPB and protamine administration, and the two isotypes of C4 (C4A and C4B) differ in their biochemical and functional properties after activation. METHODS: One hundred fifty-six pediatric patients referred for elective cardiac surgery with CPB were included in the study. C4 isotype studies were performed in plasma samples obtained before surgery, with use of agarose gel immunofixation and crossed immunoelectrophoresis. Five possible C4 phenotype groups were observed, which were abbreviated as follows: (1) AABB = no detectable null alleles, (2) A0BB = a single null allele (heterozygous) at the C4A locus, (3) 00BB = a homozygous C4A null allele, (4) AAB0 = a single null allele (heterozygous) at the C4B locus, and (5) AA00 = a homozygous C4B null allele. The patients were classified into five groups according to their C4 phenotypes. Before CPB and at 1 h after CPB, plasma protein was measured with a biuret test kit. Plasma colloid osmotic pressure was determined with a membrane osmometer. Evans blue dye was used to measure plasma volume, serum protein, intravenous protein pool, and transvascular escape rate of Evans blue dye. RESULTS: Of 156 pediatric patients enrolled, 80 were assigned to the AABB group, 28 were assigned to the A0BB group, 7 were assigned to the 00BB group, 31 were assigned to the AAB0 group, and 10 were assigned to the AA00 group, according to their C4 phenotypes. At 1 h after CPB, serum protein concentrations averaged 3.6 +/- 0.4 g/dl in patients with the 00BB C4 phenotype; this value was significantly lower (P < 0.01) than that in patients with other C4 phenotypes. The changes of intravenous protein pool and colloid osmotic pressure were comparable with the change in serum protein concentration. At 1 h after CPB, the transvascular escape rate of Evans blue dye averaged 11.5 +/- 1.3%/h in patients with the 00BB C4 phenotype; this value was significantly higher (P < 0.01) than that in patients with other C4 phenotypes. CONCLUSIONS: In this study, capillary leak syndrome induced by CPB occurred only in patients with the homozygous C4A null phenotype.

Analysis of Variance↗
PubMed1995

Lower prevalence and incidence of HIV-1 syncytium-inducing phenotype among injecting drug users compared with homosexual men.

OBJECTIVE: To study the prevalence, incidence and predictive value for progression to AIDS of the HIV-1 syncytium-inducing (SI) phenotype in HIV-infected injecting drug users (IDU) compared with HIV-infected homosexual men. DESIGN: Two prospective cohort studies on HIV-1 infection among IDU and homosexual men. METHODS: HIV-infected IDU (n = 225) and homosexual men (n = 366) without AIDS were studied from March 1989 through December 1993. Data on laboratory markers, including the presence of SI variants, demographics, behavioural characteristics and clinical events were collected at every visit. RESULTS: At baseline, SI variants were detected in 4% of IDU and 17% of homosexual men. During the study period 18 IDU and 68 homosexual men switched from non-SI to SI phenotype (4-year cumulative incidence, 14.6 and 28.4%, respectively) before AIDS diagnosis. Among participants with a documented date of HIV infection the cumulative incidence of SI was lower among IDU than homosexual men (4-year cumulative incidence, 6.2 and 20.7%, respectively). At AIDS diagnosis, 21% of all AIDS cases among IDU had the SI phenotype compared with 54% among homosexual men. In both risk groups an accelerated CD4 decline was found after the non-SI-to-SI switch. The SI phenotype appeared to be a predictor of AIDS (multivariate relative hazard, 5.33), independent of CD4 cell count and p24 antigen at baseline. In the multivariate time-dependent analysis, the relative hazard of SI phenotype decreased considerably, which is consistent with the hypothesis that the effect of SI phenotype on progression to AIDS is mediated by CD4 cell count. CONCLUSION: The SI phenotype is associated with accelerated CD4 decline and progression to AIDS in both risk groups. The remarkable lower prevalence and incidence of the SI phenotype among IDU may implicate a difference in pathogenesis and natural history of HIV infection linked to transmission group.

Adult↗
PubMed2000

Prevalence of genotypic and phenotypic resistance to anti-retroviral drugs in a cohort of therapy-naïve HIV-1 infected US military personnel.

OBJECTIVE: While transmission of drug-resistant HIV-1 has been reported, estimates of prevalence of resistance in drug-naïve populations are incomplete. We investigated the prevalence of genotypic mutations and phenotypic antiretroviral resistance in a cohort of HIV-1 infected U.S. military personnel prior to the institution of antiretroviral therapy. DESIGN: Cross-sectional cohort study. METHODS: Plasma was obtained from 114 recently HIV-1 infected subjects enrolled in an epidemiological study. Genotypic resistance was determined by consensus sequencing of a PCR product from the HIV-1 pol gene. Sequences were interpreted by a phenotypic-genotypic correlative database. Resistance phenotypes were determined by a recombinant virus cell culture assay. RESULTS: Genotypic mutations and phenotypic resistance were found at a higher than expected frequency. Resistance to non-nucleoside reverse transcriptase inhibitors was most common, with a prevalence of 15% of 95 subjects by genotype and 26% of 91 subjects by phenotype. Genotypic and phenotypic resistance respectively were found in 4% and 8% of subjects for nucleoside reverse transcriptase inhibitors and in 10% and 1% for protease inhibitors. One subject harbored virus with resistance to all three drug classes. CONCLUSIONS: A substantial frequency of resistance to antiretroviral drugs was identified in a therapy-naïve U.S. cohort. In most cases, the genotypic and phenotypic assays yielded similar results, although the genotypic assay could detect some protease inhibitor resistance-associated mutations in the absence of phenotypic resistance. These data suggest the need for optimization of treatment guidelines based on current estimates of the prevalence of drug resistance in HIV-1 seroconverters.

Adult↗
PubMed1990

Wall mannoproteins in cells from colonial phenotypic variants of Candida albicans.

Candida albicans ATCC 26555 switched at high frequency (10(-1) to 10(-3)) between several phenotypes identified by colony morphology on a defined mineral amino-acid-containing agar medium supplemented with arginine and zinc (LAZ medium). When cells taken from colonies exhibiting distinct morphologies were plated directly onto LAZ agar, spontaneous conversion to all the variant phenotypes occurred at combined frequencies of 2.1 x 10(-1) to 9.5 x 10(-3). However, when cells taken from the different colonial phenotypes were plated directly onto an undefined medium (yeast extract/peptone/dextrose; YPD medium), or first incubated in liquid YPD medium and then cloned on YPD agar, all colonies observed exhibited the same phenotype (smooth-white). When cells from the smooth-white colonies were plated as clones on LAZ agar, the original switch phenotype reappeared. These results suggest that environmental conditions such as the growth medium (and possibly the temperature) influence switching by suppressing phenotype expression, but have no effect on genotype. The variant colony morphologies also appeared to be associated with differences in the relative proportions of yeast and mycelial cells. Zymolyase digests of wall preparations obtained from cells belonging to different colonial phenotypes were analysed by SDS-PAGE. After blotting to nitrocellulose paper, the mannoproteins were stained with Concanavalin A, with a polyclonal antiserum enriched in antibodies against mycelium-specific wall components, and with a monoclonal antibody raised against a high-molecular-mass mannoprotein band (260 kDa) specific to the walls of mycelial cells. The results suggest that phenotypic switching might be associated with changes in the degree of glycosylation in high-molecular-mass mannoproteins, or in the way these mannoproteins are bound to other cell wall components.

Candida albicans↗
PubMed2005

Two site-specific recombinases are implicated in phenotypic variation and competitive rhizosphere colonization in Pseudomonas fluorescens.

The biocontrol agent Pseudomonas fluorescens F113 undergoes phenotypic variation during rhizosphere colonization, and this variation has been related to the activity of a site-specific recombinase encoded by the sss gene. Here, it is shown that a second recombinase encoded by the xerD gene is also implicated in phenotypic variation. A putative xerD gene from this strain was cloned, and sequence analysis confirmed that it encoded a site-specific recombinase of the lambda integrase family. Mutants affected in the sss or xerD genes produced a very low quantity of phenotypic variants compared to the wild-type strain, both under prolonged cultivation in the laboratory and after rhizosphere colonization, and they were severely impaired in competitive root colonization. Overexpression of the genes encoding either recombinase resulted in a substantial increment in the production of phenotypic variants under both culture and rhizosphere colonization conditions, implying that both site-specific recombinases are involved in phenotypic variation. Overexpression of the sss gene suppressed the phenotype of a xerD mutant, but overexpression of the xerD gene had no effect on the phenotype of an sss mutant. Genetic analysis of the phenotypic variants obtained after overexpression of the genes encoding both the recombinases showed that they carried mutations in the gacA/S genes, which are necessary to produce a variety of secondary metabolites. These results indicate that the Gac system is affected by the activity of the site-specific recombinases. Transcriptional fusions of the sss and xerD genes with a promoterless lacZ gene showed that both genes have a similar expression pattern, with maximal expression during stationary phase. Although the expression of both genes was independent of diffusible compounds present in root exudates, it was induced by the plant, since bacteria attached to the root showed enhanced expression.

Amino Acid Sequence↗
PubMed2003

Molecular correlates of genes exhibiting RNAi phenotypes in Caenorhabditis elegans.

Understanding genome-wide links between genotype and phenotype has generally been difficult due to both the complexity of phenotypes, and until recently, inaccessibility to large numbers of genes that might underlie a trait. To address this issue, we establish the association between particular RNAi phenotypes in Caenorhabditis elegans and sequence characteristics of the corresponding proteins and DNA. We find that genes showing RNAi phenotypes are long and highly expressed with little noncoding DNA and high rates of synonymous site substitution (KS). In addition, genes conferring RNAi phenotypes have significantly lower rates of nonsynonymous site substitution (KA). Collectively, these sequence features explain nearly 20% of the difference between the sets of loci that display or lack a RNAi-mediated effect, and reflect aspects both of the RNAi mechanism and the biological function of the genes. For example, the particularly low rate of evolution of genes in the sterility RNAi phenotype class suggests a role of C. elegans life history in shaping these patterns of sequence and expression characteristics on phenotypes. This approach also allows prediction of a set of heretofore-uncharacterized loci for which we expect future RNAi studies to reveal phenotypic effects (i.e., false negatives in present screens).

Animals↗
PubMed1985

Immune phenotype and prognosis in chronic B-lymphocytic leukaemia and leukaemic immunocytoma.

Fifty-nine patients with a leukaemic B-lymphocytic malignancy ("CLL") were studied. According to the Kiel classification, 29 patients had chronic lymphocytic leukaemia (CLL) and 30 had immunocytoma (IC). Cell surface immunoglobulin staining showed mu heavy chain phenotype in 14 patients, mu in 35, gamma in 7; in cells from 3 patients the staining was too weak to permit identification. The light chain phenotype was kappa in 39 patients, lambda in 17, and unidentified in 3. The immunoglobulin isotypes differed between the diagnoses. The gamma chain phenotype was found only in IC patients (p less than 0.02), and more CLL than IC patients showed a lambda chain phenotype (p less than 0.04). Blood lymphocytes from IC patients contained more T cells than CLL cell samples (p less than 0.002). No prognostic difference was found between the CLL and IC group. Compared to the lambda phenotype, the kappa phenotype was associated with a poorer prognosis in the IC group, but with a better prognosis in the CLL group. IC patients with mu phenotype had a poorer prognosis than those with gamma phenotype. Low relative T cell numbers were associated with a poor survival (p less than 0.01).

Aged↗
PubMed2004

Intraindividual consistency of the activated protein C resistance phenotype.

Resistance to activated protein C (APC) has been demonstrated to be a risk factor for venous thromboembolism, but it is not known whether this phenotype is consistent over time. We reinvestigated 2580 subjects from the Vicenza Thrombophilia and Atherosclerosis (VITA) Project to evaluate the prevalence of a consistent APC resistance phenotype in the population. Among the 433 subjects with an APC resistance at first visit, the phenotype was confirmed in all the 74 factor V (FV) Leiden carriers and in 124 of 359 FV Leiden negative subjects (34%). The prevalence of a confirmed phenotype, not associated with FV Leiden, was 4.8% in our population. In a subgroup of subjects previously investigated for heritability of the APC resistance, we confirmed the APC resistance phenotype in seven of 39 (17.9%) subjects with an APC resistant sibling but only in 20 of 408 (4.9%) subjects without a sibling with the same phenotype (P = 0.005). Among the 124 FV Leiden negative subjects with a persistent APC resistance phenotype, 40 (32%) had a plasma factor VIII coagulant activity level above 150 IU/dl and eight (6.4%) were carriers of the G20210A prothrombin allele. APC resistance not due to FV Leiden is a frequent and consistent phenotype in the general population, with a possibly strong genetic influence.

Activated Protein C Resistance↗
PubMed2006

Modification of a virulence-associated phenotype after growth of Listeria monocytogenes on food.

AIM: To assess the effect of different foods, which have been implicated or not in cases of listeriosis, on the in vitro virulence-associated phenotype level of different Listeria monocytogenes strains. METHODS AND RESULTS: The virulence-associated phenotype level of L. monocytogenes was studied with the in vitro cell test based on a plaque-forming assay with a human adenocarcinoma cell line (HT-29) monolayer. Three strains of L. monocytogenes were grown in preparations (homogenate, 1-mum filtrate or 0.2-mum filtrate) of different food extracts ['rillettes' (potted minced pork), milk, raw salmon and cold-smoked salmon] or in a control medium, brain heart infusion (BHI). The bacterial suspensions grown in food extracts or in BHI at 37 degrees C were diluted with their growth medium (food extract or BHI) or with minimum essential medium before seeding on confluent HT-29 cell monolayers. Filtration of food extracts had no significant effect on the plaque numbers formed by the bacteria. A significant decrease in the plaque numbers was noted for the three strains when they grew in the rillettes extracts, compared with the other food extracts and BHI. The levels of in vitro virulence-associated phenotype of the strains after growth in the rillettes extract were similar to or lower than that of the hypovirulent internal reference strain L. monocytogenes 442. After growth in milk and cold-smoked salmon, the impact on virulence-associated phenotype depended on the strain. In contrast, plaque-forming assay indicated increased virulence-associated phenotype when the strains were switched from a nutrient-rich medium (food extract or BHI) to a minimum essential medium. CONCLUSIONS: In vitro virulence-associated phenotype level of the studied strains grown in BHI or cold-smoked salmon was the same as the control virulent strain EGD. In contrast, the nutrients present in rillettes may therefore substantially reduce the number of plaques but not the growth of L. monocytogenes. The utilization of minimum essential medium as diluent attenuates changes the effect of the food extract on virulence-associated phenotype in vitro. SIGNIFICANCE AND IMPACT OF THE STUDY: In the experimental design of this study, we showed that the nature of the food could affect the in vitro virulence-associated phenotype level of L. monocytogenes.

Animals↗
PubMed2006

Vascular smooth muscle cell phenotypic plasticity and the regulation of vascular calcification.

Vascular smooth muscle cells (VSMCs) exhibit an extraordinary capacity to undergo phenotypic change during development, in vitro and in association with disease. Unlike other muscle cells they do not terminally differentiate. Development and maintenance of the mature contractile phenotype is regulated by a number of interacting transcription factors. In response to injury contractile VSMCs can be induced to change phenotype, proliferate and migrate to effect repair. On completion of the repair process VSMCs return to a nonproliferating contractile phenotype. In this way, in the context of atherosclerosis, a protective fibrous cap is formed and maintained at sites of injury. However in disease, when modulatory signals are perturbed, this phenotypic transition is dysregulated and VSMCs are induced to undergo inappropriate differentiation into cells with features of other mesenchymal lineages such as osteoblasts, chondrocytes and adipocytes. Moreover, evidence is accumulating that these aberrant phenotypic transitions contribute to the pathogenesis of vascular diseases such as atherosclerosis and Monckeberg's Sclerosis. Indeed, the osteo/chondrocytic conversion of VSMCs and the association of this phenotype with vascular calcification is a paradigm for how inappropriate differentiation can influence disease processes. Understanding of the mechanisms and signalling pathways involved in this particular phenotype change is well advanced offering the possibility for the design of successful therapeutic interventions in the future.

Calcinosis↗
PubMed1996

Comparison of the Lewis phenotypes among the different population groups of Taiwan.

In Caucasians, three red cell Lewis phenotypes are observed, namely Le (a+b-), Le (a-b+) and Le (a-b-). For Chinese living in Taiwan the Le (a+b-) phenotype is replaced by the Le (a+b+) phenotype so that the three red cell Lewis phenotypes observed in Chinese are Le (a+b+), Le (a-b+) and Le (a-b-). In addition, Chinese individuals with Le (a-b-) red cells can be subdivided into two groups, namely those who secrete both ABH and Lewis substances in saliva and those who secrete only ABH substances in saliva. However, four red cell Lewis phenotypes Le (a+b-), Le (a+b+), Le (a-b+) and Le (a-b-) are observed among some of the indigenous groups living in Taiwan. Red cell Le (a+b-) individuals among these indigenous groups can also be subdivided into at least two groups, namely those with Le(a) and Le(b) in saliva (plus varying amounts of ABH substances) and those with just Le(a) in saliva. The former are most likely a weak form of the red cell Le (a+b+) phenotype while the latter appear to be similar to the Caucasian red cell Le (a+b-) phenotype. There was also one red cell Le (a+b-) individual whose saliva had a small amount of A substance as well as Lea substance and therefore appeared to be intermediate between the above two forms of the Le (a+b-) phenotype.

Asian People↗
PubMed2005

Colonic and small-intestinal phenotypes in gastric cancers: relationships with clinicopathological findings.

The clinicopathological significance of colonic and small-intestinal phenotypes has hitherto remained unclear in gastric cancers. The purpose of the present study was therefore to examine 86 gastric carcinomas histologically and phenotypically using several phenotypic markers, including colon-specific carbonic anhydrase 1 (CA1) and sucrase as small-intestine specific marker. Of 86 gastric cancers, sucrase and CA1 expression was observed in 12 (14.0%) and only in two cases (2.3%), respectively, associated with other intestinal markers such as villin and mucin core protein (MUC)2. In the sucrase cases, expression appeared independent of the stage. However, CA1 expression was observed only in two advanced cases. No association was observed between colonic and small-intestinal phenotypes, and lymph node metastasis and postoperative survival in the advanced gastric cancer cases with intestinal phenotypic expression. Cdx2 appeared to be linked to upregulation of both CA1 and sucrase. In conclusion, the data suggest that colonic phenotype occurs rarely in gastric carcinogenesis. Colonic and small-intestinal phenotypes appear with expression of several intestinal phenotypic markers under the control of Cdx2 and presumably other related transcription factors.

Adenocarcinoma↗
PubMed2004

Renal phenotype is exacerbated in Os and lpr double mutant mice.

BACKGROUND: ROP-Os/+ mice are born with oligosyndactyly and oligonephronia and develop renal dysfunction, which includes renal tubular epithelial cell (RTC) Fas-dependent apoptosis and tubular atrophy. MRL/lpr mice harbor a Fas-inactivating mutation and develop glomerulonephritis, whereas mice expressing lpr on a C3H background demonstrate no renal phenotype. We hypothesized that crossing ROP-Os/+ with CH3-lpr/lpr mice would rescue the Os/+ renal phenotype by reducing Fas-dependent RTC apoptosis. METHODS: ROP-Os/+ mice were intercrossed with C3H-lpr/lpr mice and F(2) generation animals were phenotyped by kidney weight, serum creatinine, and albuminuria. Kidney sections were scored for histopathology and apoptosis. Univariate and multivariate analyses were used to examine additive effects of Os and lpr on renal phenotype. RESULTS: By 16 weeks, F(2)Os/+ lpr/lpr mice developed significantly more albuminuria, glomerulosclerosis, and interstitial inflammation compared to Os/++/+ mice. Glomerular cell apoptosis was increased in Os/+ lpr/lpr compared to Os/++/+ mice, with no significant difference in RTC apoptosis. A statistically significant Os-lpr effect on renal phenotype was demonstrated by multivariate analysis, which exceeded the combined independent effects if Os and lpr, indicating a biologic interaction exists between Os and lpr. CONCLUSION: Os/+ mice with a superimposed lpr mutation displayed a more severe renal phenotype, rather than phenotype rescue, suggesting that Fas pathway activation is necessary to delete cells resulting from Os-dependent injury. We further propose that an Os-lpr gene interaction and/or mixed ROP-C3H genetic background regulated the renal phenotype, consistent with the concept that chronic renal disease pathogenesis reflects effects of multiple nephropathy susceptibility alleles.

Animals↗
PubMed1989

Mucoid phenotype of Klebsiella pneumoniae is a plasmid-encoded virulence factor.

We have previously reported that the presence of a 180-kilobase plasmid encoding production of aerobactin was correlated with the virulence of Klebsiella pneumoniae K1 and K2 isolates. This work demonstrates that a variant of a K2 strain which has lost this plasmid, pKP100, becomes avirulent. Labeling of this plasmid with the mobilizable, replication-defective element pME28, used here as a mobilizable transposon, allowed the transfer of this plasmid into a plasmidless derivative. Virulence was restored upon reacquisition of this tagged plasmid, pKP101. In addition to aerobactin production, another phenotype could be correlated with the presence of this virulence plasmid: the mucoid phenotype of the bacterial colonies. Both wild-type and plasmidless strains are encapsulated, but only the former presented mucoid colonies. Participation of this phenotype in the virulence of K. pneumoniae was demonstrated by constructing a mutant altered in the plasmid gene encoding this phenotype. The resulting strain demonstrated a 1,000-fold decrease in virulence. Introduction of the recombinant plasmid pKP200 carrying the gene encoding this mucoid phenotype into Escherichia coli HB101 also led to the production of a mucoid phenotype. Rocket immunoelectrophoresis demonstrated that in E. coli this phenotype was due to the production of colanic acid. On the other hand, neither the overproduction of K2 capsular polysaccharide nor the presence of colanic acid was detected in mucoid strains of K. pneumoniae. We conclude that this mucoid phenotype is definitely an important virulence factor of K. pneumoniae. It is due to the plasmid-encoded production of a substance which is different from colanic acid and the capsular polysaccharide of K. pneumoniae.

Base Composition↗