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Slower Growth (slower + growth)
Terms modified by Slower Growth Selected AbstractsGlobal Gene Expression Differences Associated with Changes in Glycolytic Flux and Growth Rate in Escherichia coli during the Fermentation of Glucose and XyloseBIOTECHNOLOGY PROGRESS, Issue 1 2002Ramon Gonzalez The simplicity of the fermentation process (anaerobic with pH, temperature, and agitation control) in ethanologenic Escherichia coli KO11 and LY01 makes this an attractive system to investigate the utility of gene arrays for biotechnology applications. By using this system, gene expression, glycolytic flux, and growth rate have been compared in glucose-grown and xylose-grown cells. Although the initial metabolic steps differ, ethanol yields from both sugars were essentially identical on a weight basis, and little carbon was diverted to biosynthesis. Expression of only 27 genes changed by more than 2-fold in both strains. These included induction of xylose-specific operons ( xylE, xylFGHR, and xylAB) regulated by XylR and the cyclic AMP,CRP system and repression of Mlc-regulated genes encoding glucose uptake ( ptsHIcrr, ptsG) and mannose uptake ( manXYZ) during growth on xylose. However, expression of genes encoding central carbon metabolism and biosynthesis differed by less than 2-fold. Simple statistical methods were used to investigate these more subtle changes. The reproducibility (coefficient of variation of 12%) of expression measurements (mRNA as cDNA) was found to be similar to that typically observed for in vitro measurements of enzyme activities. Using Studentapos;s t test, many smaller but significant sugar-dependent changes were identified ( p < 0.05 in both strains). A total of 276 genes were more highly expressed during growth on xylose; 307 genes were more highly expressed with glucose. Slower growth (lower ATP yield) on xylose was accompanied by decreased expression of 62 genes concerned with the biosynthesis of small molecules (amino acids, nucleotides, cofactors, and lipids), transcription, and translation; 5 such genes were expressed at a higher level. In xylose-grown cells, 90 genes associated with the transport, catabolism, and regulation of pathways for alternative carbon sources were expressed at higher levels than in glucose-grown cells, consistent with a relaxation of control by the cyclic AMP,CRP regulatory system. Changes in expression of genes encoding the Embden,Meyerhof,Parnas (EMP) pathway were in excellent agreement with calculated changes in flux for individual metabolites. Flux through all but one step, pyruvate kinase, was predicted to be higher during glucose fermentation. Expression levels (glucose/xylose) were higher in glucose-grown cells for all EMP genes except the isoenzymes encoding pyruvate kinase ( pykA and pykF). Expression of both isoenzymes was generally higher during xylose fermentation but statistically higher in both strains only for pykF encoding the isoenzyme activated by fructose-6-phosphate, a key metabolite connecting pentose metabolism to the EMP pathway. The coordinated changes in expression of genes encoding the EMP pathway suggest the presence of a common regulatory system and that flux control within the EMP pathway may be broadly distributed. In contrast, expression levels for genes encoding the Pentose,Phosphate pathway did not differ significantly between glucose-grown and xylose-grown cells. [source] Prenatal growth, postnatal growth and trait anxiety in late adulthood , the Helsinki Birth Cohort StudyACTA PSYCHIATRICA SCANDINAVICA, Issue 3 2010J. Lahti Lahti J, Räikkönen K, Pesonen A-K, Heinonen K, Kajantie E, Forsén T, Osmond C, Barker DJP, Eriksson JG. Prenatal growth, postnatal growth and trait anxiety in late adulthood , the Helsinki Birth Cohort Study. Objective:, Trait anxiety may predispose to anxiety disorders and cardiovascular events. We tested whether prenatal growth or postnatal growth from birth to 11 years of age and in adulthood predict trait anxiety in late adulthood. Method:, Women (n = 951) and men (n = 753) reported trait anxiety using the Spielberger Trait Anxiety Scale at an average age of 63.4 years and growth was estimated from records. Results:, Higher trait anxiety was predicted by smaller body size at birth, in infancy and in adulthood. Moreover, faster growth particularly from seven to 11 years of age and slower growth between 11 and 63 years predicted higher trait anxiety. Conclusion:, We found a pattern of pre- and postnatal growth that predisposed to higher trait anxiety in late adulthood. This pattern resembles that found to increase the risk of cardiovascular events and, thus, points to a shared common origin in a suboptimal prenatal and childhood developmental milieu. [source] Interannual variability in hatching period and early growth of juvenile walleye pollock, Theragra chalcogramma, in the Pacific coastal area of HokkaidoFISHERIES OCEANOGRAPHY, Issue 3 2007AKIRA NISHIMURA ABSTRACT Juvenile walleye pollock of the Japanese Pacific population were collected from the Funka Bay [spawning ground; 16,64 mm fork length (FL)] in spring and the Doto area (nursery ground; 70,146 mm FL) in summer. Hatch dates were estimated by subtracting the number of otolith daily increments from sampling dates, and their early growth was back-calculated using otolith radius,somatic length relationships. Interannual change of the hatching period was observed during 2000,02, and the peaks ranged from mid-February in 2000 to early-April in 2002. In 2000, when a strong year class occurred, early life history of the surviving juveniles could be characterized by early hatching and slower growth in the larval stage (<22 mm length). Higher growth rate in 2001 and 2002 did not always lead to good survival and recruitment success. Even though their growth was slow in 2000, the larvae hatched early in the season had larger body size on a given date than faster-growing larvae hatched in later season in 2001 and 2002. Bigger individuals at a certain moment may have advantage for survival. The delay of hatching period may result in higher size-selective mortality, and as a necessary consequence, back-calculated growth in 2001 and 2002 could shift towards higher growth rate, although abundance of such a year class would be at the lower level. Variability in spawning period, early growth and their interaction might have a strong relation to larval survival through cumulative predation pressure or ontogenetic changes in food availability. [source] Differential Employment Patterns for Citizens and Non-Citizens in Science and Engineering in the United States: Minting and Competitive EffectsGROWTH AND CHANGE, Issue 4 2004Sharon G. Levin ABSTRACT The consequences of the heavy inflow of foreign talent for U.S. scientists and engineers over the period 1973-1997 are examined using data from the Survey of Doctorate Recipients. Of particular interest is whether non-citizens trained in the United States have displaced citizens from jobs in science and engineering (S&E). Using a novel adaptation of the shift-share technique, it is shown that citizen S&E doctorates have fewer jobs in S&E and fewer academic jobs than their non-citizen counterparts for two reasons: the citizen doctoral population has experienced slower growth than the non-citizen doctoral population, and citizen S&E doctorates have been displaced. Whether the displacement observed was a voluntary response of citizens to the lure of better opportunities elsewhere or an involuntary response indicative of having been pushed out by foreign talent remains to be determined. [source] Life-long protein malnutrition in the rat (Rattus norvegicus) results in altered patterns of craniofacial growth and smaller individualsJOURNAL OF ANATOMY, Issue 6 2006Shannon L. Lobe Abstract Dietary protein is a limiting factor in mammalian growth, significantly affecting the non-linear trajectories of skeletal growth. Young females may be particularly vulnerable to protein malnutrition if the restriction is not lifted before they become reproductive. With such early malnutrition, limited amino acids would be partitioned between two physiological objectives, successful reproduction vs. continued growth. Thus, the consequences of protein malnutrition could affect more than one generation. However, few studies have quantified these cross-generational effects. Our objective was to test for differences in skeletal growth in a second generation of malnourished rats compared with rats malnourished only post-weaning, the first generation and with controls. In this longitudinal study we modelled the growth of 22 craniofacial measurements with the logistic Gompertz equation, and tested for differences in the equation's parameters among the diet groups. The female offspring of post-weaning malnourished dams did not catch up in size to the first generation or to controls, although certain aspects of their craniofacial skeleton were less affected than others. The second generation's growth trajectories resembled the longer and slower growth of the first malnourished generation. There was a complex interaction between developmental processes and early nutritional environment, which affected variation of adult size. [source] Respiratory chain deficiency slows down cell-cycle progression via reduced ROS generation and is associated with a reduction of p21CIP1/WAF1JOURNAL OF CELLULAR PHYSIOLOGY, Issue 1 2006Matthias Schauen We have used HeLa cells without mitochondrial DNA (,0 -cells) and transient ,0 -phenocopies, obtained from wild-type cells by short-term treatment with ethidium bromide, to analyze how the absence of a functional mitochondrial respiratory chain slows down proliferation. We ruled out an energetic problem (ATP/ADP content) as well as defective synthesis of pyrimidine, iron-sulfur clusters or heme as important causes for the proliferative defect. Flow cytometric analysis revealed that reactive oxygen species were reduced in ,0 -cells and in ,0 -phenocopies, and that, quite unusually, all stages of the cell cycle were slowed down. Specific quenching of mitochondrial ROS with the ubiquinone analog MitoQ also resulted in slower growth. Some important cell-cycle regulators were reduced in ,0 -cells: cyclin D3, cdk6, p18INK4C, p27KIP1, and p21CIP1/WAF1. In the ,0 -phenocopies, the expression pattern did not fully duplicate the complex response observed in ,0 -cells, and mainly p21CIP1/WAF1 was downregulated. Activities of the growth regulatory PKB/Akt and MAPK/ERK-signaling pathways did not correlate with proliferation rates of ,0 -cells and ,0 -phenocopies. Our study demonstrates that loss of a functional mitochondrial electron transport chain inhibits cell-cycle progression, and we postulate that this occurs through the decreased concentration of reactive oxygen species, leading to downregulation of p21CIP1/WAF1. J. Cell. Physiol. 209: 103,112, 2006. © 2006 Wiley-Liss, Inc. [source] Delayed kinetics of DNA double-strand break processing in normal and pathological agingAGING CELL, Issue 1 2008Olga A. Sedelnikova Summary Accumulation of DNA damage may play an essential role in both cellular senescence and organismal aging. The ability of cells to sense and repair DNA damage declines with age. However, the underlying molecular mechanism for this age-dependent decline is still elusive. To understand quantitative and qualitative changes in the DNA damage response during human aging, DNA damage-induced foci of phosphorylated histone H2AX (,-H2AX), which occurs specifically at sites of DNA double-strand breaks (DSBs) and eroded telomeres, were examined in human young and senescing fibroblasts, and in lymphocytes of peripheral blood. Here, we show that the incidence of endogenous ,-H2AX foci increases with age. Fibroblasts taken from patients with Werner syndrome, a disorder associated with premature aging, genomic instability and increased incidence of cancer, exhibited considerably higher incidence of ,-H2AX foci than those taken from normal donors of comparable age. Further increases in ,-H2AX focal incidence occurred in culture as both normal and Werner syndrome fibroblasts progressed toward senescence. The rates of recruitment of DSB repair proteins to ,-H2AX foci correlated inversely with age for both normal and Werner syndrome donors, perhaps due in part to the slower growth of ,-H2AX foci in older donors. Because genomic stability may depend on the efficient processing of DSBs, and hence the rapid formation of ,-H2AX foci and the rapid accumulation of DSB repair proteins on these foci at sites of nascent DSBs, our findings suggest that decreasing efficiency in these processes may contribute to genome instability associated with normal and pathological aging. [source] Size-independent growth in fishes: patterns, models and metricsJOURNAL OF FISH BIOLOGY, Issue 10 2008D. B. Sigourney A combination of a dynamic energy budget (DEB) model, field data on Atlantic salmon Salmo salar and brown trout Salmo trutta and laboratory data on Atlantic salmon was used to assess the underlying assumptions of three different metrics of growth including specific growth rate (G), standardized mass-specific growth rate (GS) and absolute growth rate in length (GL) in salmonids. Close agreement was found between predictions of the DEB model and the assumptions of linear growth in length and parabolic growth in mass. Field data comparing spring growth rates of age 1+ year and 2+ year Atlantic salmon demonstrated that in all years the larger age 2+ year fish exhibited a significantly lower G, but differences in growth in terms of GS and GL depended on the year examined. For brown trout, larger age 2+ year fish also consistently exhibited slower growth rates in terms of G but grew at similar rates as age 1+ year fish in terms of GS and GL. Laboratory results revealed that during the age 0+ year (autumn) the divergence in growth between future Atlantic salmon smolts and non-smolts was similar in terms of all three metrics with smolts displaying higher growth than non-smolts, however, both GS and GL indicated that smolts maintain relatively fast growth into the late autumn where G suggested that both smolts and non-smolts exhibit a sharp decrease in growth from October to November. During the spring, patterns of growth in length were significantly decoupled from patterns in growth in mass. Smolts maintained relatively fast growth though April in length but not in mass. These results suggest GS can be a useful alternative to G as a size-independent measure of growth rate in immature salmonids. In addition, during certain growth stanzas, GS may be highly correlated with GL. The decoupling of growth in mass from growth in length over ontogeny, however, may necessitate a combination of metrics to adequately describe variation in growth depending on ontogenetic stage particularly if life histories differ. [source] Growth, maturity and fecundity of wolffish Anarhichas lupus L. in Icelandic watersJOURNAL OF FISH BIOLOGY, Issue 4 2006Á. Gunnarsson Fecundity, maturity and the relationship between growth and maturity of common wolffish Anarhichas lupus were studied in Icelandic waters. A total of 788 female common wolffish were sampled in two areas: one in the relatively warm sea west of Iceland and the other in the colder sea east of Iceland. No difference was detected in fecundity of common wolffish between areas. The time from the onset of the cortical alveolus stage until spawning, was on average, 10 years in the east and 8 years in the west area. Common wolffish in the east area reached cortical alveolus stage, on average, at a greater age but similar size compared to common wolffish in the west area. Similarly, common wolffish started spawning, on average, at greater age and larger size in the east than in the west area. Common wolffish grew faster in the west than in the east area. Spawning common wolffish grew faster than common wolffish at the cortical alveolus stage in both areas. The relationship between growth and maturity for common wolffish in Icelandic waters appeared to be related to temperature, characterized by fast growth and early maturation in the west and slower growth and delayed maturation in the east. [source] Effect of cisapride on gastric emptying in premature infants with feed intoleranceJOURNAL OF PAEDIATRICS AND CHILD HEALTH, Issue 6 2001CP Barnett Objective: To assess the effect of cisapride on gastric emptying and gastro-oesophageal reflux (GOR) symptoms in preterm infants with feed intolerance. Methods: Sixteen preterm infants (gestational age 24,35 weeks) with feed intolerance were enrolled in the study. Infants were randomized to receive 7 days of cisapride 0.2 mg/kg four times a day, immediately followed by 7 days of placebo or vice versa. Gastric emptying was measured using the [13C]-octanoic acid breath test prior to study entry and repeated on day 5, 6 or 7 after randomization and 5, 6 or 7 days after crossover. The symptoms of GOR were monitored during the study period using a standardized reflux chart. Weight was recorded daily. Results: There was no change in gastric emptying in infants prescribed cisapride (gastric half-emptying time (t1/2) 31.9 ± 4.7 vs 34.2 ± 3.9 min for placebo vs cisapride, respectively; P = 0.65). Infants on cisapride had slower growth and there was no change in reflux symptoms. Conclusions: The use of cisapride in preterm infants with feed intolerance cannot be recommended. [source] Employee Training in SMEs: Effect of Size and Firm Type,Family and NonfamilyJOURNAL OF SMALL BUSINESS MANAGEMENT, Issue 2 2007Bernice Kotey The study examined the main and interaction effects of size and firm type on a variety of informal and formal training programs in small and medium-sized enterprises (SMEs). Samples of 448 family and 470 nonfamily SMEs were separated into four size groups and differences were assessed using multivariate analyses of variance. The results point to prevalence of informal training for all sizes and an increase in adoption of formal, structured, and development-oriented training with increasing firm size (especially for firms with 20,99 employees). This pattern was evident for nonfamily but not for family firms. For family firms, formal training programs increased significantly during the critical growth phase only (20,49 employees). Gaps in employee training between the two types of firms were greatest at 50,99 employees but narrowed thereafter at 100,199 employees. The approach to employee training in family SMEs is in consonance with their slower growth, informal management styles, limited financial resources, and greater emphasis on efficiency compared with nonfamily SMEs. [source] Effect of Diets Formulated with Native Peruvian Plants on Growth and Feeding Efficiency of Red Pacu (Piaractus brachypomus) JuvenilesJOURNAL OF THE WORLD AQUACULTURE SOCIETY, Issue 3 2006Maria E. Palacios We evaluated the effects of casein-based semipurified diets, alone or supplemented with native Peruvian plants, on growth, feed efficiency, and histology of the digestive tract of red pacu, Piaractus brachypomus, juveniles over an 8-wk feeding trial. Three tanks were randomly assigned to one of four casein,gelatin (40:8) diets containing a supplement of 15% wheat meal (control) or an identical level of substitution of three South American native plant as follows: camu-camu fruit (Myrciaria dubia), aguaje fruit (Mauritia flexuosa), or maca tuber meal (Lepidium meyenii). The fish (initial weight, 2.04 ± 0.06 g) were fed experimental diets at decreasing feeding rates from 4 to 2.6% of body weight. After 8 weeks of feeding, fish fed a diet supplemented with maca meal showed significantly higher (P < 0.05) weight gain, specific growth rate, protein efficiency ratio (PER), apparent net protein utilization (NPU), and instantaneous feed intake than fish fed other diets. Feed conversion ratio (FCR), PER, and NPU in fish fed the casein,gelatin diet supplemented with maca meal were among the best ever reported in the scientific literature, 0.64 ± 0.03, 3.13 ± 0.15 and 23.8 ± 2.0, respectively. The camu-camu meal had a negative impact on diet palatability and utilization, which resulted in slower growth. The stomach, intestine, pancreas, and pyloric caeca at the start and end of the experiment showed normal differentiation and appearance of cells and tissues. The liver parenchyma showed lipid infiltration and pigment accumulation in all samples at the initiation of the experiment and may be attributed to the period of decreased feed intake prior to the study. At the end of the study, similar histopathologies were recorded in all samples from the control and camu-camu groups. Normal liver histology (polyhedral hepatocytes with centrally located nuclei) was observed in two of three samples from the maca group and all the samples from the group that was fed the aguaje-supplemented diet. [source] Pilot Production of Hatchery-Reared Summer Flounder Paralichthys dentatus in a Marine Recirculating Aquaculture System: The Effects of Ration Level on Growth, Feed Conversion, and SurvivalJOURNAL OF THE WORLD AQUACULTURE SOCIETY, Issue 1 2005Patrick M. Carroll Pilot-scale trials were conducted to evaluate growout performance of hatchery-reared summer flounder fingerlings in a state-of-the-art recirculating aquaculture system (RAS). The outdoor RAS consisted of four 4.57-m dia × 0.69-m deep (vol. =11.3 m3) covered, insulated tanks and associated water treatment components. Fingerlings (85.1 g mean initial weight) supplied by a commercial hatchery were stocked into two tanks at a density of 1,014 fish/tank (7.63 kg/m3). Fish were fed an extruded dry floating diet consisting of 50% protein and 12% lipid. The temperature was maintained between 20 C and 23 C and the salinity was 34 ppt. Under these conditions, growth, growth variation (CVwt), feed utilization, and survival of fish fed to 100% and 82% of a satiation rate were compared. Due to clear changes in growth patterns during the study, data was analyzed in three phases. During phase 1 (d 1,d 196), fish showed rapid growth, reaching a mean weight of 288 g ± 105 and 316 g ± 102, with a CVwt of 0.36 and 0.32 and FCR's of 1.38 and 1.36 in the subsatiation and satiation groups, respectively. During phase 2 (d 196,d 454), fish displayed slower growth reaching mean weights of 392 g ± 144 and 436 g ± 121, with a CVwt of 0.37 and 0.28, and increasing FCR's of 3.45 and 3.12 in the subsatiation and satiation groups, respectively. During phase 3 (d 454,d 614), fish showed little growth reaching mean weights of 399 g ± 153 and 440 g ± 129, with a CVwt of 0.38 and 0.29 in the subsatiation and satiation groups, respectively. Over the entire growout period (d 1,d 614), feed conversion ratios were 2.39 and 2.37 and survival was 75% and 81 % in the subsatiation and satiation treatments, respectively. The maximum biomass density reached during the study was 32.3 kg/m3. The satiation feed rate was superior to the 82% satiation rate, since it maximized growth rates, with no effect on FCR. The higher CVwt in the subsatiation group suggests increased competition for a restricted ration led to a slower growth with more growth variation. The decrease in growth in phases 2 and 3 was probably related to a high percentage of slower growing male fish in the population and the onset of sexual maturity. This study demonstrated that under commercial scale conditions, summer flounder can be successfully grown to a marketable size in a recirculating aquaculture system. Based on these results, it is recommended that a farmer feed at a satiation rate to minimize growout time. More research is needed to maintain high growth rates through marketable sizes through all-female production and/or inhibition of sexual maturity. [source] The Effects of Exogenous Bovine Growth Hormone and Placental Lactogen on Juvenile Striped Bass Morone saxatilis Feed and Growth EfficiencyJOURNAL OF THE WORLD AQUACULTURE SOCIETY, Issue 1 2000Amy S. Hunt Striped bass Morone saxatilis under normal pond-reared conditions usually requires 14,18 mo to grow out to market weight. This includes a winter of comparatively slower growth which could possibly be overcome through hormonally induced acceleration of growth. Thus, the objective of this experiment was to test the hypothesis that bovine growth hormone and bovine placental lactogen increase growth in striped bass in a dose dependent manner. A secondary objective was to determine the effect of these hormones on body composition. Variables tested were weight gain, length gain, condition factor, feed conversion, and body composition. Fish injected biweekly with 10 ,g/g body weight, bovine placental lactogen (P < 0.09) or bovine growth hormone (P < 0.11) increased body weight. Fish injected with 1 or 10 ,g/g body weight bovine placental lactogen (P < 0.10) or bovine growth hormone (P < 0.10) increased body length during the 12-wk study period. Proximate analysis indicated that bovine growth hormone increased protein content (10 ,g/g; P < 0.10) and decreased fat content (1 and 10 ,g/g; P < 0.10). No significant differences occurred in feed conversions. We conclude that bovine growth hormone and bovine placental lactogen are effective in increasing body growth in striped bass. [source] Early weaning of winter flounder (Pseudopleuronectes americanus Walbaum) larvae on a commercial microencapsulated dietAQUACULTURE RESEARCH, Issue 6 2003I Ben Khemis Abstract Like most small marine fish larvae, the stomachs of winter flounder Pseudopleuronectes americanus are undeveloped at first feeding and have relatively reduced digestive capacity. This work was undertaken to test whether larvae at the onset of stomach differentiation (larval size about 5.5 mm) could be early weaned onto a commercial microencapsulated diet. We assessed the effect of early weaning by first comparing growth performance (standard length, total protein content and age at metamorphosis) of larvae fed enriched live prey from first feeding to a size of 5.5 mm and then reared on three different feeding regimes until metamorphosis: (1) live prey (LP) as a control group; (2) mixed feeding of live prey and microencapsulated diet (LP-ME); (3) exclusively microencapsulated diet (ME) after fast weaning over 4 days (to a larval size of 6.2 mm). No differences were observed between larval development in the two first groups, which began metamorphosis at 40 days old. The larvae of the third group showed significantly slower growth that resulted in a delay of 4 days in the onset of metamorphosis. Differences in live prey availability between the treatments and the short transition period to allow the larvae to adapt to the new diet were identified as possible contributing factors to the slower growth and to the delay in metamorphosis of early weaned larvae. In a second experiment, the transitional weaning period was increased until the larvae were 6.6 mm in length. Weaning at that size resulted in no slowing of growth or delay in metamorphosis, suggesting that the feeding schedule was adequate. [source] Toe-bud clipping of juvenile small marsupials for ecological field research: No detectable negative effects on growth or survivalAUSTRAL ECOLOGY, Issue 8 2009D. O. FISHER Abstract Toe clipping is widely used to permanently mark many species of small vertebrates including marsupials, particularly didelphids and dasyurids. Small marsupials are marked as juveniles, by removing the tip of developing toe buds. It has recently been shown that survival and/or recapture probability decreases with increasing number of toes clipped in frogs. Because of this and other animal welfare concerns, toe clipping of adult vertebrates is increasingly being discouraged. The short- and long-term effects of toe-bud clipping have not been evaluated in marsupials. We used an experiment to test if marking more toes results in slower growth or higher mortality in the brown antechinus (Antechinus stuartii, Dasyuridae) in the short or long term. We found no harmful effects of toe-bud clipping. There were no infections associated with clipping, marking more toes did not reduce growth in young or adults, and did not affect survival of young in captivity, survival of independent animals in the wild, or recapture probability. Toe-bud clipping is done at an extremely immature stage, when the area cut is tiny and perception and memory of pain is unlikely to be a problem. We suggest that toe-bud clipping is a humane and benign method of permanently marking antechinuses, and probably also the young of other morphologically similar small marsupials. [source] Ethnicity and fetal growth in FijiAUSTRALIAN AND NEW ZEALAND JOURNAL OF OBSTETRICS AND GYNAECOLOGY, Issue 4 2004Matthews MATHAI Abstract Background:, Indigenous Fijians and the descendants of Asian Indians constitute the two major ethnic groups in Fiji. There are differences between the two groups in perinatal outcomes. Aims:, To study fetal growth patterns in the two ethnic groups and to ascertain the influence, if any, of ethnicity on fetal growth. Methods:, A longitudinal study was carried out on women with sure dates, regular cycles, no known risk factor complicating pregnancy and having their first antenatal examination before 20 weeks. Symphysis-fundal height, biparietal diameter, abdominal circumference and femur length were measured by the same observer at recruitment and at follow-up visits until delivery. Infant measurements were recorded soon after birth. Results:, Indian babies were on average 795 g lighter, had 5.5 days shorter mean length of gestation and slower growth of biparietal diameter and abdominal circumference when compared to Fijian babies. Ethnicity of the mother was significantly associated with the difference in growth even after adjusting for other factors known to influence fetal growth. Conclusion:, Given the ethnic differences in fetal growth and maturation, it would be appropriate to use ethnicity-specific standards for perinatal care in Fiji. [source] An endogenous melanocyte-inhibiting tripeptide pyroGlu-Phe-GlyNH2 delays in vivo growth of monoclonal experimental melanomaCELL PROLIFERATION, Issue 2 2000D. S. Gembitsky The melanocyte-inhibiting tripeptide (MTP) pyroGlu-Phe-GlyNH2 is present in tissue cultures of non-transformed melanocytes and melanoma cells and influences melanocyte growth in vitro. The objective of the present study was to investigate a possible effect of MTP on the in vivo growth of B16A2, a monoclonal experimental melanoma. The B16A2 clone was established by the limited dilution technique. It has a reduced DNA content and displays slower growth both in vivo and in vitro compared to the parent cell line (B16). B16A2 cells were injected subcutaneously into hairless mice at four sites (300 000 cells in 0.25 ml buffer/site). MTP was given by i.p. injection 3 times a week at two concentrations (1 pmol and 1 nmol/animal). The control animals received the equal volume of solvent. The animals were sacrificed 1 and 2 weeks after tumour transplantation, and all tumours were weighed. One week after transplantation, the animals who received 1 pmol MTP had fewer tumours and a reduced tumour load. Two weeks after the transplantation, the differences between control and treated animals were no longer observed. The results indicate that MTP temporarily delays in vivo tumour growth. [source] Transfection and ligation of CD40 in human oral keratinocytes affect proliferation, adhesion and migration but not apoptosis in vitroCLINICAL & EXPERIMENTAL DERMATOLOGY, Issue 2 2006M. Villarroel Dorrego Summary Aims:, CD40 expression is restricted to Keratinocytes of normal epidermis or stratified squamous epithelium of oral mucosa. Ligation of CD40 inhibits keratinocyte proliferation and apoptosis. The aim of this study was to investigate the functional significance of CD40 in the proliferation, apoptosis, adhesion and migration of human oral keratinocytes in vitro. Methods., The CD40-negative oral keratinocyte line OSC19, its CD40-positive transfected derivative (OSC19T-CD40) and null transfectants (OSC19T-control), with and without stimulation by soluble protein CD40 ligand (sCD40L) or anti-CD40 antibodies were used. Results., OSC19T-CD40 showed significantly (P < 0.001) slower growth than the null transfectants and parent cells. OSC19T-CD40 proliferation was inhibited by ligation with sCD40L and blocking by two anti-CD40 antibodies, but stimulated by a third. Binding of CD40 with ligand or antibody had no effect on keratinocyte apoptosis in any cell line. The capacity of OSC19T-CD40 cells to adhere to CD40L-coated wells was significantly greater (P < 0.001) than that of parent OSC19 and OSC19T-control cells, and the migration rate of OSC19T-CD40 cells was significantly higher than parent OSC19 (P = 0.038 on fibronectin, P = 0.004 on Matrigel) or OSC19T-control (P =0.017 on fibronectin, P = 0.013 on Matrigel) cells. Conclusions., CD40 is an important molecule in keratinocyte homeostasis, and has more than one ligand. The ligand that is bound may be critical in oral epithelial homeostasis, the development of malignancy and the behaviour of the subsequent tumour. [source] | ||||||||||||||||