Changes In Phenotype Expression Research Articles

Trinexapac-ethyl alters the expression of descriptors for identifying white oat cultivars

Trinexapac-ethyl reduces lodging in white oat, but its use in seed production fields requires knowledge of its impact on the expression of descriptors, under penalty of compromising the identification of cultivars. In this work, six white oat cultivars of different stature classes (Low: Brisasul and URS Taura; Medium: IPR Artemis; High: URS Altiva, URS Brava and URS 21) were evaluated for the state of expression of descriptors in response to the application of 100 g a.i ha-1 of trinexapac-ethyl when the primary stalk had the first visible node and the second perceptible node. Over two years, the experiments were carried out with different rainfall conditions (2017/2018), in a split-plot design, with three replications. The phenotypic variability in response to product application varied according to cultivar and year. Seven out of 23 descriptorschanged the state of expression in response to trinexapac-ethyl, in greater magnitude for plant length, followed by lemma length and panicle branching position, cycle, floral and glume axis lengths, and density of plants panicle. Trinexapac-ethyl reduced plant length, floral axis and glume, anticipated flowering, increased panicle density and lemma length. Regardless of year, the cultivars with the greatest phenotypic stability to the application of trinexapac-ethyl were Brisasul (96%) and Taura (91%), and the least stable was URS Altiva (83%). The stability of the other cultivars was yeardependent, with the greatest change in phenotypic expression in the year of lower water availability.

A Phase 1 Study of XmAb18968, a CD3-CD38 Bispecific Antibody for the Treatment of Patients with Relapsed/Refractory Acute Leukemia and T Cell Lymphoblastic Lymphoma

Background:Outcomes of adults with relapsed/refractory T-cell acute lymphoblastic leukemia or lymphoma (T-ALL or T-LBL respectively) and acute myeloid leukemia (AML) have remained poor despite the availability of newer agents. CD38 is a 45 kDa transmembrane glycoprotein expressed by lymphoid and myeloid cells with several important functions including a role in immune escape from tumor cells [Chillemi A et al. Front Immunol 2017, Furano A et al. J Immunol 1990]. Several studies have demonstrated that CD38 is expressed in tumor cells of patients with T-ALL and AML and potentially targetable using CD38 blocking agents [Naik J et al. Haematologica 2019, Bride KL et al. Blood 2018, Tembhare et al. J Immunother Cancer 2020, Farber M et al. ASH 2018]. XmAb18968 is structurally distinct CD3-CD38 bi-specific T-cell engager with a full fragment crystallizable (Fc) domain modified to minimize Fcγ receptor binding and non-selective activation of T cells and other immune effector cells. XmAb18968 has optimized relative affinities for both CD3 and CD38 which results in reduced cytokine release without compromising target cell killing. We hypothesize targeting CD38 in relapsed/refractory- T-cell ALL/LBL and AML is safe and feasible using XmAb18968, a novel CD3-CD38 bispecific antibody.Study design and methods:This is an investigator-sponsored multi-institutional phase I study evaluating the safety and tolerability of XmAb18968. Patients aged 18 years or above with T-ALL, T-LBL or AML (including undifferentiated leukemia and bi phenotypic leukemia), in relapsed/refractory status (at least one line of prior therapy) including measurable residual disease relapse, CD38 expression ≥ 20%, and adequate organ function will be eligible. Major exclusion criteria are hematopoietic cell transplantation (HCT) within 6 months of enrollment, active acute GVHD, veno-occlusive disease, and acute promyelocytic leukemia. The study is planned to be conducted at 6 sites in United States.The primary endpoint is to determine the recommended phase 2 dose (RP2D) and toxicity profile of XmAb18968. The secondary endpoints include determination of response rates, duration of response, survival and pharmacokinetics. Exploratory endpoints include correlation of responses with genomic profile, assessment of serum cytokine response, identifying the changes in phenotypic expression of activated T-cells and leukemic cells, correlation of the phenotypic expression with changes in the transcriptome at the single-cell level, proteomics evaluation of cytokine secretion at the single-cell level and correlation of response with N-glycan profiling, quantitative site-occupancy and direct glycopeptide analysis.The study will follow 3+3 design for dose escalation and de-escalation in case of dose limiting toxicity (DLT). Dose escalation will proceed in two separate groups: Group A for subjects with T-ALL and T-LBL and Group B for subjects with AML. Patients will be entered sequentially to each dose level, starting with the first dose level. The DLT observation period for dose-escalation will be 28-days. RP2D will be defined as the highest dose level at which none of the first 3 treated subjects, or no more than 1 of the first 6 treated subjects experience a DLT. A minimum of 24 and a maximum of 60 patients will be needed for the dose escalation phase. DisclosuresGuru Murthy: Curio Sciences: Honoraria; Techspert: Consultancy; Qessential: Honoraria; CancerExpertNow: Honoraria; DAVA Oncology: Honoraria; TG Therapeutics: Other: Advisory board meeting; Cardinal health: Honoraria; Guidepoint: Consultancy. Johnson: Miltenyi Biotec: Research Funding. Abedin: AltruBio: Research Funding; Amgen: Honoraria; Agios: Honoraria; Helsinn: Research Funding; Pfizer: Research Funding; Astellas Pharma Inc.: Research Funding; Actinium: Research Funding. Stock: Pfizer: Consultancy, Honoraria, Research Funding; amgen: Honoraria; agios: Honoraria; jazz: Honoraria; kura: Honoraria; kite: Honoraria; morphosys: Honoraria; servier: Honoraria; syndax: Consultancy, Honoraria; Pluristeem: Consultancy, Honoraria. Shah: Precision Biosciences: Consultancy; Kite, a Gilead Company: Consultancy, Honoraria, Other: Expenses, Research Funding; Pharmacyclics/Janssen: Honoraria, Other: Expenses; Acrotech/Spectrum: Honoraria; BeiGene: Consultancy, Honoraria; Amgen: Consultancy; Pfizer: Consultancy, Other: Expenses; Novartis: Consultancy, Other: Expenses; Bristol-Myers Squibb/Celgene: Consultancy, Other: Expenses; Adaptive Biotechnologies: Consultancy; Servier Genetics: Other; Jazz Pharmaceuticals: Research Funding; Incyte: Research Funding. Leonard: Amgen: Research Funding; Takeda: Membership on an entity's Board of Directors or advisory committees. Pratz: Agios: Consultancy; BMS: Consultancy, Honoraria; Novartis: Consultancy; Astellas: Consultancy, Honoraria, Research Funding; Cellgene: Consultancy, Honoraria; Millenium: Research Funding; University of Pennsylvania: Current Employment; Abbvie: Consultancy, Honoraria, Research Funding. Luger: Syros: Honoraria; Agios: Honoraria; Daiichi Sankyo: Honoraria; Jazz Pharmaceuticals: Honoraria; Brystol Myers Squibb: Honoraria; Acceleron: Honoraria; Astellas: Honoraria; Pfizer: Honoraria; Onconova: Research Funding; Celgene: Research Funding; Biosight: Research Funding; Hoffman LaRoche: Research Funding; Kura: Research Funding. Badar: Pfizer Hematology-Oncology: Membership on an entity's Board of Directors or advisory committees. Atallah: Novartis: Consultancy, Honoraria, Research Funding; Amgen: Consultancy; Abbvie: Consultancy, Speakers Bureau; Takeda: Consultancy, Research Funding; BMS: Honoraria, Speakers Bureau; Pfizer: Consultancy, Research Funding.

Predictive value of phenotypic signatures of bladder cancer response to cisplatin-based neoadjuvant chemotherapy

BackgroundCisplatin-based neoadjuvant chemotherapy (NAC) for muscle-invasive urothelial carcinoma of the bladder confers only a modest survival advantage. Patients with pathologic progression on NAC have poor outcomes related to a delay in definitive surgical management. ObjectiveTo characterize the value of epithelial-mesenchymal transition (EMT) effectors and other novel biomarkers to predict response to NAC. MethodsA tissue microarray was constructed from patients with clinical stage T2 urothelial carcinoma of the bladder using transurethral resection (TUR) specimens (N = 69) and case-matched post-NAC cystectomy specimens (N = 51). Patients were stratified based on pathologic response to NAC and cancer-specific survival. Biomarker expression in TUR specimens was correlated with pathologic response to NAC and clinical outcomes. Phenotypic changes in expression induced by cisplatin-based NAC were characterized in primary TUR and post-NAC cystectomy and lymph node metastasis specimens. ResultsIncreased expression of mesenchymal markers and actin-cytoskeleton regulators, as well as low apoptosis index, in TUR specimens was associated with pathologic progression on cisplatin-based NAC. Overexpression of N-cadherin and decreased apoptosis was predictive of disease-specific mortality. NAC decreased cofilin phosphorylation and induced a mesenchymal-epithelial transition phenotype. ConclusionsThe epithelial-mesenchymal transition phenotype and actin-cytoskeleton remodeling are associated with pathologic progression on NAC. Chemotherapy induced an mesenchymal-epithelial transition phenotype and decreased cofilin phosphorylation, providing new insights into therapeutic resistance mechanisms. Primary tumors with high apoptosis rates exhibited favorable response to NAC and lower mortality rates, indicating that these tumors may be sensitized to therapy. Further validation will establish these novel signatures as predictors of therapeutic response.

Genetic polymorphisms namely TLR2 Gene Arg753gln and Arg677trp polymorphisms and tuberculosis: Comparison on the effects of molecular weight alterations

Background: Tuberculosis is an important mycobacterial infection. This problem is still the present public health problem in several countries around the world. The genetic underlying factor is usually mentioned for the effect on the natural history of tuberculosis infection. Methods: Here, the authors perform a standard assessment on the molecular change due to TLR2 gene Arg753Gln and Arg677Trp polymorphisms and further study on the effect on the corresponding phenotypic expression changes. Results: The molecular weight changes comparing to naive molecule in cases of Arg753Gln and Arg677Trp polymorphisms are equal to –16.1% and +17.2%, respectively. Conclusion: According to the molecular structure analysis, Arg753Gln has a relationship with active tuberculosis whereas Arg677Trp polymorphism is not.

* Tissue-Specific Extracellular Matrix Enhances Skeletal Muscle Precursor Cell Expansion and Differentiation for Potential Application in Cell Therapy.

Skeletal muscle precursor cells (MPCs) are considered a key candidate for cell therapy in the treatment of skeletal muscle dysfunction due to injury, disease, or age. However, expansion of a sufficient number of functional skeletal muscle cells in vitro from a small tissue biopsy has been challenging due to changes in phenotypic expression of these cells under traditional culture conditions. Thus, the aim of the study was to develop a better culture system for the expansion and myo-differentiation of MPCs that could further be used for therapy. For this purpose, we developed an ideal method of tissue decellularization and compared the ability of different matrices to support MPC growth and differentiation. Porcine-derived skeletal muscle and liver and kidney extracellular matrix (ECM) were generated by decellularization methods consisting of distilled water, 0.2 mg/mL DNase, or 5% fetal bovine serum. Acellular matrices were further homogenized, dissolved, and combined with a hyaluronic acid-based hydrogel decorated with heparin (ECM-HA-HP). The cell proliferation and myogenic differentiation capacity of human MPCs were assessed when grown on gel alone, ECM, or each ECM-HA-HP substrate. Human MPC proliferation was significantly enhanced when cultured on the ECM-HA-HP substrates compared to the other substrates tested, with the greatest proliferation on the muscle ECM-HA-HP (mECM-HA-HP) substrate. The number of differentiated myotubes was significantly increased on the mECM-HA-HP substrate compared to the other gel-ECM substrates, as well as the numbers of MPCs expressing specific myogenic cell markers (i.e., myosin, desmin, myoD, and myf5). In conclusion, skeletal mECM-HA-HP as a culture substrate provided an optimal culture microenvironment potentially due to its similarity to the in vivo environment. These data suggest a potential use of skeletal muscle-derived ECM gel for the expansion and differentiation of human MPCs for cell-based therapy for skeletal muscle dysfunction.

Evolutionary rescue and local adaptation under different rates of temperature increase: a combined analysis of changes in phenotype expression and genotype frequency in Paramecium microcosms.

Evolutionary rescue (ER) occurs when populations, which have declined due to rapid environmental change, recover through genetic adaptation. The success of this process and the evolutionary trajectory of the population strongly depend on the rate of environmental change. Here we investigated how different rates of temperature increase (from 23 to 32°C) affect population persistence and evolutionary change in experimental microcosms of the protozoan Paramecium caudatum. Consistent with theory on ER, we found that those populations experiencing the slowest rate of temperature increase were the least likely to become extinct and tended to be the best adapted to the new temperature environment. All high-temperature populations were more tolerant to severe heat stress (35, 37°C), indicating a common mechanism of heat protection. High-temperature populations also had superior growth rates at optimum temperatures, leading to the absence of a pattern of local adaptation to control (23°C) and high-temperature (32°C) environments. However, high-temperature populations had reduced growth at low temperatures (5-9°C), causing a shift in the temperature niche. In part, the observed evolutionary change can be explained by selection from standing variation. Using mitochondrial markers, we found complete divergence between control and high-temperature populations in the frequencies of six initial founder genotypes. Our results confirm basic predictions of ER and illustrate how adaptation to an extreme local environment can produce positive as well as negative correlated responses to selection over the entire range of the ecological niche.

Lifetime changes in phenotypic expression and evolutionary potential of female mating traits in Drosophila melanogaster

Recognition of the ubiquity of female multiple mating has caused an important shift in sexual selection research, emphasizing the adaptive nature of female mating strategies. While phenotypic changes in female mating traits have been previously studied, little is known about the genetic basis of female mating behaviour and its potential to respond to selection at different stages throughout an individual's life. Using a large quantitative genetic breeding design, we observed lifetime female mating behaviour in Drosophila melanogaster to examine the effect of female age and mating history on three key mating traits: courtship latency, mating latency and copula duration. Courtship latency (time until males initiate courtship) decreased with the cumulative number of females' previous matings. Mating latency (defined here as the time between the beginning of courtship and the start of copulation) increased with female age, and copula duration was found to decrease as females aged. We calculated quantitative genetic estimates for mating traits in virgin females and at the females' third mating to examine changes in the evolutionary potential of mating traits. We found considerable additive genetic variation in courtship latency and mating latency measured in virgin females. Copula duration displayed no heritable variation among females across sire families, but male effects were consistent with the idea that this trait is under male control. Heritability estimates differed significantly from zero in virgin females for courtship latency and mating latency but not when females were mating for the third time. However, overlapping 84% confidence intervals between heritability estimates obtained from virgin and mated females suggest that female mating strategies may have the potential to respond to selection at these different life stages.

Status of subclinical mastitis and associated risk factors in Indian water buffalo in Doaba region of Punjab, India.

Abstract Sub clinical mastitis in buffalo is considered as multi-factorial disease, which leads to huge economic losses by reducing the quality and quantity of the milk. It does not lead to any change in phenotypic expression, so diagnosed through various tests as California mastitis test, Somatic cell count, Electrical conductivity test etc. Although bacteria are considered to be the main causative agent for mastitis, beside this farm management practices are found to be associated with the disease. In the present study, the pathogens related to the occurrence of the disease were examined via bacteriological culture of milk sample of the animal. Animal wise prevalence of sub clinical mastitis was found to be (20.4%), out of this 7.8%, 9.8%, 2.8% were found to be effected with latent mastitis, specific mastitis and nonspecific mastitis respectively .On the basis of individual quarter, the highest prevalence was in LH (33.9%), followed by RH (24%) and RF (22.4%) and the least prevalence in LF (14.5%). The microorganisms isolated from sub clinical mastitis constituted Staphylococci (39%), Streptococci (31%), Corynebacterium (25%) and E. coli .(5%).Farm management associated determinants (Type of feed, type of floor, education of the owner, feeding after milking, type of labor) were studied in association with sub clinical mastitis. Out of these education of the owner , type of labor and feeding after milking were found to be significantly associated with disease occurrence (p<0.05). While looking at the animal determinants in association with sub clinical mastitis in the present investigation buffaloes with higher parity showed more risk of developing sub clinical mastitis. So the present investigation helps to understand the various risk factors for the occurrence of sub clinical mastitis in water buffalo in Doaba region of Punjab.

Phenotypic switching inCandida tropicalis: association with modification of putative virulence attributes and antifungal drug sensitivity

Although Candida tropicalis has become an increasingly important human pathogen, little is known regarding its potential to cause disease. In this study we evaluated the phenotypic switching ability of C. tropicalis and analyzed the effect of switching on biological properties related to virulence factors. We demonstrated that C. tropicalis switched spontaneously, reversibly and at high frequency (10(-1) to 10(-3)) when grown on yeast extract-peptone-D-glucose (YPD) agar medium. Phenotypic switching in five clinical isolates of C. tropicalis resulted in colonies exhibiting the following morphologies: crepe, rough, crater, irregular center, mycelial and diffuse. The majority of the variant colonies were associated with higher percentages of filamentous growth relative to their parental unswitched isolates. Significant differences (P < 0.05) in the production of hemolytic factor were found between most of the switched variants and their respective parental counterparts. Variant colonies exhibiting the crepe (derived from isolates 49.07 and 100.10) and rough phenotype (derived from isolate 49.07) had higher biofilm formation than their parental counterparts exhibiting a smooth dome surface (P < 0.05). Our data revealed that switching was correlated with changes in the in vitro minimum inhibitory concentrations (MICs) of a subset of the switched variants phenotypes to itraconazole. While the MIC to itraconazole was higher for crepe variant compared with its parental isolate 49.07, the rough variant of 100.10 had a lower MIC to this antifungal agent. The presented data support the role of phenotypic switching in promoting changes in phenotypic expression of putative virulence traits and itraconazole susceptibility of clinical isolates of C. tropicalis.

Seasonal Variability in Trypsin and α-amylase Activities Caused by the Molting Cycle and Feeding Habits of Juvenile Pink Shrimp Farfantepenaeus duorarum (Burkenroad, 1939)

ABSTRACT In view of the relationship between shifts in diet composition and the activity of digestive enzymes in penaeid shrimp, the present study focused on the analysis of digestive trypsin and α-amylase activities of wild Farfantepenaeus duorarum (Burkenroad, 1939) juveniles and their changes in phenotypic expression, during the molt cycle as endogenous factor and their changes due to different feeding regimes (exogenous factor) in relation with δ13C and δ15N isotopic signature as an index of food assimilation induced by the seasonal availability of food items in the nursery area. Wild juveniles of F. duorarum were captured from April 2007 to February 2008, in the Celestun coastal lagoon, Yucatan, Mexico. Samplings were carried out considering all quarters of the lunar cycle and in each of the recognized seasons for this region: dry, rainy, and the Nortes (North Wind). Copepods and amphipods were the main source of food for juveniles of F. duorarum. Values of δ13C in the muscular tissue were near -20‰ ...

Effects of Irradiation on Growth and Differentiation-Related Gene Expression in Osteoblasts

Osteoblasts are bone-forming cells that are responsible for the production of bone extracellular matrix. Osteoradionecrosis is a complication of radiation therapy for carcinoma of the head and neck that occurs in 3% to 8.2% of irradiated patients. The irradiation effect on osteoblast differentiation has not been fully elucidated. The objective of our research was to elucidate the effects of radiation on the growth and differentiation-related gene expression in osteoblast in vitro. Three differentiation-related genes, alkaline phosphatase, type I collagen, and osteocalcin, were tested in our experiment. The results showed that radiation inhibited the proliferation of the osteoblasts in a dose-dependent manner and induced G2/M cell cycle arrest. Irradiation, 4 and 8 Gy, enhanced the differentiation-related gene expression of MC3T3-E1 cells 7 days after irradiation. However, the differentiation-related gene expression was decreased 21 days after irradiation in the 4- and 8-Gy groups. This work presents the dynamic phenotypic expression changes of osteoblastic cells after x-ray irradiation.

Predicting chemical impacts on vertebrate endocrine systems

Animals have evolved diverse protective mechanisms for responding to toxic chemicals of both natural and anthropogenic origin. From a governmental regulatory perspective, these protective responses complicate efforts to establish acceptable levels of chemical exposure. To explore this issue, we considered vertebrate endocrine systems as potential targets for environmental contaminants. Using the hypothalamic-pituitary-thyroid (HPT), hypothalamic-pituitary-gonad (HPG), and hypothalamic-pituitary-adrenal (HPA) axes as case examples, we identified features of these systems that allow them to accommodate and recover from chemical insults. In doing so, a distinction was made between effects on adults and those on developing organisms. This distinction was required because endocrine system disruption in early life stages may alter development of organs and organ systems, resulting in permanent changes in phenotypic expression later in life. Risk assessments of chemicals that impact highly regulated systems must consider the dynamics of these systems in relation to complex environmental exposures. A largely unanswered question is whether successful accommodation to a toxic insult exerts a fitness cost on individual animals, resulting in adverse consequences for populations. Mechanistically based mathematical models of endocrine systems provide a means for better understanding accommodation and recovery. In the short term, these models can be used to design experiments and interpret study findings. Over the long term, a set of validated models could be used to extrapolate limited in vitro and in vivo testing data to a broader range of untested chemicals, species, and exposure scenarios. With appropriate modification, Tier 2 assays developed in support of the U.S. Environmental Protection Agency's Endocrine Disruptor Screening Program could be used to assess the potential for accommodation and recovery and inform the development of mechanistically based models.

Fhit, Mlh1, P53 and phenotypic expression in the early stage of colorectal neoplasms

There are two different pathways for the development of colorectal carcinoma (CRC), adenoma-carcinoma sequence (ACS) and de novo (DN) carcinogenesis. To clarify the molecular and clinicopathological characteristics in colorectal carcinogenesis, we examined endoscopically resected specimens of 30 adenomas, 30 carcinoma in adenomas (CIAs), and 18 early pure colorectal carcinomas without any adenoma component (EPCs, so called DN carcinoma) and compared the expression of Fhit, Mlh1, Msh2, P53 and cellular phenotype (HGM, MUC2 and CD10). Markedly reduced or absent Fhit expression was noted in 8 (44%) of 18 EPCs, but none of the adenomas or CIAs (p<0.0001). Six (33%) of 18 EPCs showed loss of Mlh1 expression, but rarely in adenomas and CIAs (p=0.008). This altered Fhit expression was significantly higher in submucosal invasive cancers (p=0.001), lymphatic or venous invasive cancers (p=0.0018), and tumors with altered expression of Mlh1 (p=0.01). The incidence of P53 overexpression was significantly higher in EPCs (39%) and CIAs (27%) than in adenomas (3.3%) (p<0.05). There were significant differences in phenotypic expression between the adenomatous and carcinomatous areas. Moreover, in CIAs and EPCs, the rate of P53 overexpression was significantly higher in the CD10-positive cases (53%) than CD10-negative cases (19%) (p=0.04). The present findings suggested that aberrant Fhit and Mlh1 expression could be related to DN carcinogenesis and that P53 overexpression and changes in phenotypic expression could contribute to the malignant transformation of colorectal precursor lesions.

Role of mast cells and their mediators in failing myocardium under mechanical ventricular support

Background Mast cells have been implicated in tissue remodeling and fibroblast stimulation. We explored the effect of mechanical support by left ventricular assist device (LVAD) in failing myocardium and looked into grade and distribution of interstitial fibrosis, mast cell density, mast cell phenotypes and basic fibroblast growth factor (bFGF) expression pre- and post-LVAD. Methods Myocardial tissue was obtained from 20 patients with end-stage cardiomyopathy at the time of LVAD implantation and LVAD removal and from 7 donor hearts not used for transplantation. Tissue sections were stained for mast cells using tryptase as a marker and the myocardial fibrosis was measured. Double staining for tryptase and chymase was performed for detection of chymase-positive mast cells. Fluorescent microscopy showed the relationship of mast cells to bFGF, and bFGF expression was quantified by Western blot. Results There was a significant increase in mast cells in heart failure vs normal myocardium. A secondary increase in mast cells occurred after long-term (>40 days) support compared with matched pre-LVAD samples (mean ± SEM; 57.4 ± 8.6 cells/10 fields vs 45.1 ± 7.6 SEM cells/10 fields, p < 0.01). The secondary increase in mast cells was associated specifically with an increase in chymase-negative mast cells ( p < 0.01). These findings are statistically significant with concurrent decreased expression of bFGF and decreased fibrosis in the same patient tissues ( p < 0.01). Conclusions We suggest that, under long-term support, there is a change in phenotypic expression in mast cells, which can alter fibroblast functions. The decreased myocardial bFGF levels might be the result of these phenotypically altered mast cells.

Early onset of the maximum protein anabolic effect induced by isoproterenol in chick skeletal and cardiac muscle.

Prolonged (120 days) oral administration of a beta adrenoceptor agonist, isoproterenol hydrochloride (dose = 1.5 mg/kg body weight) resulted in an increase in the live weight of growing chicks (Callus domesticus). Measurement of dry muscle mass and total proteins in muscle homogenates from M. pectoralis major. M. petoralis minor suggested a muscle hypertrophy largely responsible for this live weight increase. Further, an increase in organ weight and total tissue proteins supported cardiac hypertrophy in chicks as a result of isoproterenol administration. Sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) revealed alterations in actin myosin profiles implying a drug induced change in phenotypic expression of myofibrillar component of both skeletal and cardiac muscle. The results suggest that prolonged treatment of chicks produced changes that were not much different from those recorded immediately within a fortnight.

Behaviour of moderately differentiated osteoblast-like cells cultured in contact with bioactive glasses.

Bioactive glasses have been shown to stimulate osteogenesis both in vivo and in vitro. However, the molecular mechanisms underlying this process are still poorly understood. In this study, we have investigated the behaviour of osteoblast-like cells (MG63), cultured in the presence of bioglass particles. Three types of granules were used: 45S5 bioactive glass, 45S5 granules preincubated in tris buffer and 60S non-reactive glass, used as control. Phase contrast microscopy permitted step-by-step visualization of cell cultures in contact with the particles. Ultrastructural observations of undecalcified sections revealed direct contacts of the cells and an electron-dense layer located at the periphery of the material. Protein synthesis was evaluated biochemically and showed a gradual increase throughout the culture time in the three types of cultures. Alkaline phosphatase was detected in situ, in clusters of packed cells either in contact with the material or in the background cell layer. Semi-quantitative RT-PCR analysis of the main osteoblastic markers showed that gene expression was maintained in all three cultures. The fact that osteocalcin was not detected, supports the fact that the MG63 cell line is composed of less differentiated osteogenic cells rather than mature osteoblasts. We also demonstrated for the first time in this cell line, the expression of Msx-2, Dlx-3 and Dlx-7 homeogenes, known to regulate in vivo foetal skeletogenesis as well as adult skeletal regeneration. However, no significant differences could be recognised in the expression pattern of bone markers between the three types of cultures. Yet these preliminary results indicate that bioactive glasses provided a suitable environment for the growth and proliferation of osteoblasts in vitro, since no drastic changes in phenotype expression of pre-osteoblasts was noted.

Dyslipidemia in young Japanese children: its relation to familial hypercholesterolemia and familial combined hyperlipidemia.

Most cases of dyslipidemia found in adults are non-familial. However, in children, especially young children, dyslipidemias other than familial hypercholesterolemia (FH) have not yet been characterized. From April 1990 to March 1999, 56 181 children were screened, and 1380 showed abnormal levels of apolipoprotein B (more than 2.5 standard deviations above the mean). Among these, 1198 were re-examined and further characterized by measuring lipids and apolipoproteins, and by their familial histories. Seventy-seven percent of the children (928 of 1198) recalled were diagnosed as being dyslipidemic. Ninety-one children were FH, 423 were type IIa, 128 were type IIb, 98 were type IV, and 188 were hypoalphalipoproteinemia. The presumed incidence of FH was 0.19%, IIa 0.87%, IIb 0.26%, IV 0.20%, and hypoalphalipoproteinemia 0.39%, taking into account the percentage of subjects who refused recall. At regular follow-ups, in many children with type IIb, the phenotypic expression changes from type IIb to IIa or IV. Thus, lipid and apolipoprotein levels were determined in 77 family members in 34 families of children with type IIb. Forty-five family members were dyslipidemic (type IIa 18, type IIb 11, type IV 16). As a result, 27 children (79%) with type IIb met the criteria for familial combined hyperlipidemia. Children with dyslipidemia had more family or genetic background than adults. Unexpectedly, children with type IIb were mostly familial combined hyperlipidemia. Thus, setting appropriate eating patterns during childhood might be important for normalizing risk factors for atherosclerotic coronary heart disease, especially in children with FH or type IIb.

Vascular smooth muscle cell phenotypic modulation in culture is associated with reorganisation of contractile and cytoskeletal proteins

Smooth muscle cells (SMC) exhibit a functional plasticity, modulating from the mature phenotype in which the primary function is contraction, to a less differentiated state with increased capacities for motility, protein synthesis, and proliferation. The present study determined, using Western analysis, double-label immunofluorescence and confocal microscopy, whether changes in phenotypic expression of rabbit aortic SMC in culture could be correlated with alterations in expression and distribution of structural proteins. "Contractile" state SMC (days 1 and 3 of primary culture) showed distinct sorting of proteins into subcellular domains, consistent with the theory that the SMC structural machinery is compartmentalised within the cell. Proteins specialised for contraction (alpha-SM actin, SM-MHC, and calponin) were highly expressed in these cells and concentrated in the upper central region of the cell. Vimentin was confined to the body of the cell, providing support for the contractile apparatus but not co-localising with it. In line with its role in cell attachment and motility, beta-NM actin was localised to the cell periphery and basal cortex. The dense body protein alpha-actinin was concentrated at the cell periphery, possibly stabilising both contractile and motile apparatus. Vinculin-containing focal adhesions were well developed, indicating the cells' strong adhesion to substrate. In "synthetic" state SMC (passages 2-3 of culture), there was decreased expression of contractile and adhesion (vinculin) proteins with a concomitant increase in cytoskeletal proteins (beta-non-muscle [NM] actin and vimentin). These quantitative changes in structural proteins were associated with dramatic changes in their distribution. The distinct compartmentalisation of structural proteins observed in "contractile" state SMC was no longer obvious, with proteins more evenly distributed throughout the cytoplasm to accommodate altered cell function. Thus, SMC phenotypic modulation involves not only quantitative changes in contractile and cytoskeletal proteins, but also reorganisation of these proteins. Since the cytoskeleton acts as a spatial regulator of intracellular signalling, reorganisation of the cytoskeleton may lead to realignment of signalling molecules, which, in turn, may mediate the changes in function associated with SMC phenotypic modulation.

Of genes, environment, and destiny

The target article approaches individual differences in terms of phenotypic differences developing through the interaction between a specific genetic make up and environmental variables. This interaction is proposed to be cooperative and oriented toward a progressive stabilisation of the trait. However, experimental data from animal studies indicate that environmental pressure promotes dramatic changes in phenotypic expression in mature organisms. Indeed, environmental constraint not only promotes the phenotypic expression of facilitated VTA-NAS DA transmission in genotype-resistant individuals; it also inhibits its expression in genetically prone individuals. This is in line with negative genotype-environment correlation revealed by behavior genetics.

Changes in Phenotypic Expression of Osteoblasts after X Irradiation

Changes in the phenotypic expression of osteoblasts after X irradiation were investigated. Osteoblast-like MC3T3-E1 cells at the actively proliferating, confluent and postproliferation stages were subjected to 10 Gy X irradiation. Irradiation at the confluent stage enhanced accumulation of type I collagen normalized to the DNA content. Irradiation at all stages down-regulated the expression of osteocalcin, but the levels of osteopontin and osteonectin mRNAs were unchanged from the control level. After irradiation at the later stages, the time-dependent increase in alkaline phosphatase activity per cell exceeded that in the control cells. The localization of alkaline phosphatase-positive cells was concordant with that of calcification. In addition, the quality of the calcium deposits was found to be similar to that in control cells as determined by energy dispersive spectrometry and the ratio of calcium to phosphorus, even if the cells were not exactly the same morphologically. The changes in phenotypic expression observed here are closely related to the enhancement of calcification observed in a previous study.