Showing papers by "University of Utah published in 1994"
TL;DR: A strong candidate for the 17q-linked BRCA1 gene, which influences susceptibility to breast and ovarian cancer, has been identified by positional cloning methods.
Abstract: A strong candidate for the 17q-linked BRCA1 gene, which influences susceptibility to breast and ovarian cancer, has been identified by positional cloning methods. Probable predisposing mutations have been detected in five of eight kindreds presumed to segregate BRCA1 susceptibility alleles. The mutations include an 11-base pair deletion, a 1-base pair insertion, a stop codon, a missense substitution, and an inferred regulatory mutation. The BRCA1 gene is expressed in numerous tissues, including breast and ovary, and encodes a predicted protein of 1863 amino acids. This protein contains a zinc finger domain in its amino-terminal region, but is otherwise unrelated to previously described proteins. Identification of BRCA1 should facilitate early diagnosis of breast and ovarian cancer susceptibility in some individuals as well as a better understanding of breast cancer biology.
6,118 citations
TL;DR: A large number of patients with progressive fibrosis have no known underlying cause of disease and the prognosis is poor, suggesting that the disease is likely to get worse as they age.
Abstract: Progressive fibrosis in the kidney, liver, lung, heart, bone marrow, and skin is both a major cause of suffering and death and an important contributor to the cost of health care. All of this is li...
2,974 citations
TL;DR: Findings suggest that MTS1 mutations are involved in tumor formation in a wide range of tissues.
Abstract: A putative tumor suppressor locus on the short arm of human chromosome 9 has been localized to a region of less than 40 kilobases by means of homozygous deletions in melanoma cell lines. This region contained a gene, Multiple Tumor Suppressor 1 (MTS1), that encodes a previously identified inhibitor (p16) of cyclin-dependent kinase 4. MTS1 was homozygously deleted at high frequency in cell lines derived from tumors of lung, breast, brain, bone, skin, bladder, kidney, ovary, and lymphocyte. Melanoma cell lines that carried at least one copy of MTS1 frequently carried nonsense, missense, or frameshift mutations in the gene. These findings suggest that MTS1 mutations are involved in tumor formation in a wide range of tissues.
2,855 citations
TL;DR: This analysis localized a second breast cancer susceptibility locus, BRCA2, to a 6-centimorgan interval on chromosome 13q12-13, which preliminary evidence suggests suggests confers a high risk of breast cancer but does not confer a substantially elevated risk of ovarian cancer.
Abstract: A small proportion of breast cancer, in particular those cases arising at a young age, is due to the inheritance of dominant susceptibility genes conferring a high risk of the disease. A genomic linkage search was performed with 15 high-risk breast cancer families that were unlinked to the BRCA1 locus on chromosome 17q21. This analysis localized a second breast cancer susceptibility locus, BRCA2, to a 6-centimorgan interval on chromosome 13q12-13. Preliminary evidence suggests that BRCA2 confers a high risk of breast cancer but, unlike BRCA1, does not confer a substantially elevated risk of ovarian cancer.
1,933 citations
TL;DR: In this paper, the risks of breast and ovarian cancer from the occurrence of second cancers in individuals with breast cancer, and examined the risk of other cancers in BRCA1 carriers.
1,826 citations
TL;DR: Results suggest that mutation of BRCA1 may not be critical in the development of the majority of breast and ovarian cancers that arise in the absence of a mutant germline allele.
Abstract: Loss of heterozygosity data from familial tumors suggest that BRCA1, a gene that confers susceptibility to ovarian and early-onset breast cancer, encodes a tumor suppressor. The BRCA1 region is also subject to allelic loss in sporadic breast and ovarian cancers, an indication that BRCA1 mutations may occur somatically in these tumors. The BRCA1 coding region was examined for mutations in primary breast and ovarian tumors that show allele loss at the BRCA1 locus. Mutations were detected in 3 of 32 breast and 1 of 12 ovarian carcinomas; all four mutations were germline alterations and occurred in early-onset cancers. These results suggest that mutation of BRCA1 may not be critical in the development of the majority of breast and ovarian cancers that arise in the absence of a mutant germline allele.
1,284 citations
TL;DR: This article found that the average stock market reaction to poison pill announcements is positive when the board has a majority of outside directors and negative when it does not, and that the probability that a subsequent control contest is associated with an auction is also positively related to the fraction of outsiders on the board.
1,277 citations
TL;DR: Results indicate that Ang II induces mesangial cell synthesis of matrix proteins and show that these effects are mediated by Ang II induction of TGF-beta expression, which may well contribute to glomerulosclerosis in vivo.
Abstract: Angiotensin II (Ang II) has been implicated in the development of progressive glomerulosclerosis, but the precise mechanism of this effect remains unclear. In an experimental model, we have shown previously that TGF-beta plays a key role in glomerulosclerosis by stimulating extracellular matrix protein synthesis, increasing matrix protein receptors, and altering protease/protease-inhibitor balance, thereby inhibiting matrix degradation. We hypothesized that Ang II contributes to glomerulosclerosis through induction of TGF-beta. Ang II treatment of rat mesangial cells in culture increased TGF-beta and matrix components biglycan, fibronectin, and collagen type I at both the mRNA and protein levels in a time- and dose-dependent manner. Saralasin, a competitive inhibitor of Ang II, prevented the stimulation. Ang II also promoted conversion of latent TGF-beta to the biologically active form. Coincubation of mesangial cells with Ang II and neutralizing antibody to TGF-beta blocked the Ang II-induced increases in matrix protein expression. Continuous in vivo administration of Ang II to normal rats for 7 d resulted in 70% increases in glomerular mRNA for both TGF-beta and collagen type I. These results indicate that Ang II induces mesangial cell synthesis of matrix proteins and show that these effects are mediated by Ang II induction of TGF-beta expression. This mechanism may well contribute to glomerulosclerosis in vivo.
1,041 citations
TL;DR: This study represents a unique comprehensive population-based study of familial cancer and will be useful in generating hypotheses about specific genetic and environmental factors that can be tested in genetic linkage and case-control studies.
Abstract: BACKGROUND Cancer has long been recognized to have a familial component. Elevated risks for cancers at the same site for relatives of cancer probands have been reported for both common cancers and a number of the rarer cancer sites. For a particular cancer site, however, the estimated risks to relatives have varied considerably depending on criteria for selection of probands, how cancers were determined in relatives, and overall study design. Not surprisingly, the estimated risks of other cancers in relatives of probands with cancer at a given site have been subject to even more variation. PURPOSE The aim of this study was to use the Utah Population Database resource to systematically study familial clustering of 28 distinct cancer site definitions among first-degree relatives (parents, siblings, and off-spring) of cancer probands. METHODS We estimated familial relative risks from the Utah Population Database by identifying all cases of cancer in these first-degree relatives. These observed values were compared with those expected based on cohort-specific internal rates calculated from 399,786 relatives of all individuals in the Utah Population Database known to have died in Utah. RESULTS All sites showed an excess of cancers of the same site among relatives, with thyroid and colon cancers and lymphocytic leukemia showing the highest familial risks. When the analyses were restricted to cases with early ages at diagnosis, increased familial components for most cancer sites became evident. A significant difference in familial relative risk (FRR) between male (FRR = 4.04; 95% confidence interval [CI] = 3.13-5.07) and female (FRR = 2.24; 95% CI = 1.54-3.08) probands was found for colon cancer. Highly significant familial associations (one-sided; P < .001) were found among breast, colon, and prostate cancers and between breast and thyroid cancers. Statistically significant (one-sided, P < .01) associations were also found between tobacco-associated sites (lung, larynx, lip, and cervix). CONCLUSIONS This study represents a unique comprehensive population-based study of familial cancer. The familial associations reported here will be useful in generating hypotheses about specific genetic and environmental factors that can be tested in genetic linkage and case-control studies.
995 citations
TL;DR: In this article, the interactions of three proteoglycans of the decorin family, decorin, biglycan and fibromodulin, with transforming growth factor beta (TGF-beta) were analyzed.
Abstract: We have analysed the interactions of three proteoglycans of the decorin family, decorin, biglycan and fibromodulin, with transforming growth factor beta (TGF-beta). The proteoglycan core proteins, expressed from human cDNAs as fusion proteins with Escherichia coli maltose-binding protein, each bound TGF-beta 1. They showed only negligible binding to several other growth factors. Intact decorin, biglycan and fibromodulin isolated from bovine tissues competed with the fusion proteins for the TGF-beta binding. Affinity measurements suggest a two-site binding model with Kd values ranging from 1 to 20 nM for a high-affinity binding site and 50 to 200 nM for the lower-affinity binding site. The stoichiometry indicated that the high-affinity binding site was present in one of ten proteoglycan core molecules and that each molecule contained a low-affinity binding site. Tissue-derived biglycan and decorin were less effective competitors for TGF-beta binding than fibromodulin or the non-glycosylated fusion proteins; removal of the chondroitin/dermatan sulphate chains of decorin and biglycan (fibromodulin is a keratan sulphate proteoglycan) increased the activities of decorin and biglycan, suggesting that the glycosaminoglycan chains may hinder the interaction of the core proteins with TGF-beta. The fusion proteins competed for the binding of radiolabelled TGF-beta to Mv 1 Lu cells and endothelial cells. Affinity labelling showed that the binding of TGF-beta to betaglycan and the type-I receptors in Mv 1 Lu cells and to endoglin in endothelial cells was reduced, but the binding to the type-II receptors was unaffected. TGF-beta 2 and 3 also bound to all three fusion proteins. Latent recombinant TGF-beta 1 precursor bound slightly to fibromodulin and not at all to decorin and biglycan. The results show that the three decorin-type proteoglycans each bind TGF-beta isoforms and that slight differences exist in their binding properties. They may regulate TGF-beta activities by sequestering TGF-beta into extracellular matrix.
932 citations
TL;DR: A locus for familial melanoma, MLM, has been mapped within the same interval on chromosome 9p21 as the gene for a putative cell cycle regulator, p16INK4 (CDKN2) MTS1, suggesting that CDKN2 is a good candidate for MLM.
Abstract: A locus for familial melanoma, MLM, has been mapped within the same interval on chromosome 9p21 as the gene for a putative cell cycle regulator, p16INK4 (CDKN2) MTS1. This gene is homozygously deleted from many tumour cell lines including melanomas, suggesting that CDKN2 is a good candidate for MLM. We have analysed CDKN2 coding sequences in pedigrees segregating 9p melanoma susceptibility and 38 other melanoma-prone families. In only two families were potential predisposing mutations identified. No evidence was found for heterozygous deletions of CDKN2 in the germline of melanoma-prone individuals. The low frequency of potential predisposing mutations detected suggests that either the majority of mutations fall outside the CDKN2 coding sequence or that CDKN2 is not MLM.
TL;DR: The recommendations for monitoring and selection of patients for liver biopsy identify patients at potential risk for CSLD, and thus significantly reduce the number or patients who would be exposed to this procedure.
Abstract: Methotrexate (MTX) has become an important drug in the treatment of rheumatoid arthritis (RA). The American College of Rheumatology convened a committee to assess the risks of development of clinically significant liver disease (CSLD) during MTX treatment, to evaluate the risk and role of surveillance liver biopsies, and to provide recommendations about monitoring patients for liver toxicity. The committee recommends obtaining liver blood tests (alanine aminotransferase [ALT], aspartate aminotransferase [AST], alkaline phosphatase, albumin, bilirubin), hepatitis B and C serologic studies, and other standard tests including complete blood cell count and serum creatinine tests prior to starting treatment with MTX. A pretreatment liver biopsy should be considered only for patients with a history of prior excessive alcohol consumption, persistently abnormal baseline AST values, or chronic hepatitis B or C infection. At intervals of every 4-8 weeks the AST, ALT, and albumin levels should be monitored. Routine surveillance liver biopsies are not recommended for RA patients receiving traditional doses of MTX. However, a biopsy should be performed if a patient develops persistent abnormalities on liver blood tests. These are defined as elevations (above the upper limit of laboratory normal) in the AST in 5 of 9 determinations within a given 12-month interval (6 of 12 if tests are performed monthly) or a decrease in serum albumin below the normal range. The recommendations for monitoring and selection of patients for liver biopsy identify patients at potential risk for CSLD, and thus significantly reduce the number or patients who would be exposed to this procedure. Close monitoring is essential to reduce the risk of unrecognized serious liver disease. These recommendations should be revised as necessary to reflect new and compelling information.
TL;DR: Ubiquitin-mediated proteolysis provides an important mechanism for regulating a variety of cellular processes and proteins conjugated to polymers of ubiquitin may be selected for degradation by a single subunit of the 26 S protease complex.
TL;DR: The level of intracellular Ca regulates many cellular processes, including neurotransmitter and hormone secretion, the activity of ion channels and enzymes, cytoskeletal function, cell proliferation, and gene expression.
Abstract: The level of intracellular Ca regulates many cellular processes, including neurotransmitter and hormone secretion, the activity of ion channels and enzymes, cytoskeletal function, cell proliferation, and gene expression. Voltage-sensitive Ca channels are among the most heterogeneous of ion channels. In neurons, Ca channels differ in cellular location, biophysical and pharmacological properties, and modulation. A single neuron generally contains multiple types of Ca channels, and such channels are central to the integration and expression of activity in the nervous system. It is clearly important to understand the functional significance of Ca channel diversity; a major research effort that is under way has made clear that different calcium channel types are all part of a family of multisubunit ion channels.
TL;DR: In this article, the underlying construct of a life-cycle stage has been studied in the context of an organization life cycle, and it has been shown that the structure of such a life cycle can be traced back to the organization itself.
Abstract: Over the years much has been written about the organization life cycle, yet there has been remarkably little attention given to the underlying construct of a life-cycle stage. It is proposed in thi...
TL;DR: It is suggested that the catalytic activity of the Fet3 protein is required for cellular iron accumulation, similar to that of the blue multicopper oxidoreductases.
TL;DR: The identification and characterization of CTR1, a gene in the yeast S. cerevisiae that encodes a multispanning plasma membrane protein specifically required for high affinity copper transport into the cell, provides an unexpected mechanistic link between the uptake of copper and iron.
TL;DR: A comprehensive listing is made of posttranscriptionally modified nucleosides from RNA reported in the literature through mid-1994, with the largest number and greatest structural diversity in tRNA, 79; and 28 in rRNA, 12 in mRNA, 11 in snRNA and 3 in other small RNAs.
Abstract: A comprehensive listing is made of posttranscriptionally modified nucleosides from RNA reported in the literature through mid-1994. Included are chemical structures, common names, symbols, Chemical Abstracts registry numbers (for ribonucleoside and corresponding base), Chemical Abstracts Index Name, phylogenetic sources, and initial literature citations for structural characterization or occurrence, and for chemical synthesis. The listing is categorized by type of RNA: tRNA, rRNA, mRNA, snRNA, and other RNAs. A total of 93 different modified nucleosides have been reported in RNA, with the largest number and greatest structural diversity in tRNA, 79; and 28 in rRNA, 12 in mRNA, 11 in snRNA and 3 in other small RNAs.
TL;DR: Repeated plasma exchanges in one seriously ill child transiently reduced serum titers of GluR3 antibodies, decreased seizure frequency, and improved neurologic function, suggesting an autoimmune process may underlie Rasmussen's encephalitis.
Abstract: Rasmussen's encephalitis is a progressive childhood disease of unknown cause characterized by severe epilepsy, hemiplegia, dementia, and inflammation of the brain. During efforts to raise antibodies to recombinant glutamate receptors (GluRs), behaviors typical of seizures and histopathologic features mimicking Rasmussen's encephalitis were found in two rabbits immunized with GluR3 protein. A correlation was found between the presence of Rasmussen's encephalitis and serum antibodies to GluR3 detected by protein immunoblot analysis and by immunoreactivity to transfected cells expressing GluR3. Repeated plasma exchanges in one seriously ill child transiently reduced serum titers of GluR3 antibodies, decreased seizure frequency, and improved neurologic function. Thus, GluR3 is an autoantigen in Rasmussen's encephalitis, and an autoimmune process may underlie this disease.
TL;DR: Differences between sites in northern Utah and interior Alaska were explained by vulnerability to embolism caused by freeze-thaw cycles, whereas most conifers were entirely resistant, whereas dicot trees were vulner- able.
Abstract: Xylem embolism was measured in nine tree species for one or more years. Species were ring-porous (Quercus sp.), diffuse-porous (Alnus, Betula, Populus spp.) or coniferous (Picea, Larix, Abies spp.). Intraspecific (Populus tremuloides) and intrageneric (Betula, Alnus) comparisons were made between sites in northern Utah and interior Alaska. Most embolism, >90% in some dicot species, occurred in winter. Within sites, dicot trees embolized more than conifers. Between sites, Alaskan dicot trees embolized less than their Utah counterparts. Differences were explained by vulnerability to embolism caused by freeze-thaw cycles. Most conifers were entirely resistant, whereas dicot trees were vulner- able. Less embolism in Alaskan dicot trees was associated with fewer freeze-thaw events in Alaska vs. Utah. Vulnerability was positively correlated with conduit volume and hy- draulic conductance per unit xylem area (ks). Tracheids were superior to vessels in avoiding freeze-thaw-induced embolism, and had lower k,. At the other extreme, ring-porous xylem had the highest k, but lost > 90% of hydraulic conductance after a single freeze-thaw event. Vulnerability to water-stress-induced cavitation was not correlated with conduit volume or k,. Dicot species either reversed winter embolism by refilling vessels with positive root pressures during spring (Betula, Alnus spp.), or tolerated it and relied on new xylem pro- duction to restore hydraulic conductance (Quercus sp.). Conifers reversed embolism by refilling tracheids in the absence of positive pressure. Populus species behaved inconsis- tently, showing some reversal one year but none the next. Even without embolism reversal, Populus species had hydraulic conductances per unit leaf area equal to other diffuse-porous species.
TL;DR: Spirometry is the measurement of the movement of air into and out of the lungs during various breathing maneuvers, and is the most widely used such test.
Abstract: Pulmonary-function tests provide objective, quantifiable measures of lung function. They are used to evaluate and monitor diseases that affect heart and lung function, to monitor the effects of environmental, occupational, and drug exposures, to assess risks of surgery, and to assist in evaluations performed before employment or for insurance purposes. The indications for pulmonary-function tests are summarized in Table 1. Spirometric examination, the most widely used such test, is the focus of this paper. Spirometry is the measurement of the movement of air into and out of the lungs during various breathing maneuvers. Such examinations should be readily available and routinely . . .
Journal Article•
TL;DR: This study used information processing paradigms to provide a detailed examination of executive function abilities in autism and suggests a new conceptual framework and general method for investigating the cognitive underpinnings of neurodevelopmental disorders.
Abstract: This study used information processing paradigms to provide a detailed examination of executive function abilities in autism. The performance of non-retarded autistic children was compared with that of two matched control groups, one with Tourette Syndrome and the other developmentally normal. Autistic subjects performed as well as controls on tasks requiring global-local processing and inhibition of neutral responses. In contrast to both control groups, however, the autistic sample was significantly impaired on a measure of cognitive flexibility. The performance of children with Tourette Syndrome did not differ from that of normal controls on any task. These results refine our knowledge about executive dysfunction in autism and suggest a new conceptual framework and general method for investigating the cognitive underpinnings of neurodevelopmental disorders.
TL;DR: In this paper, the authors used SPLITT-fractionation to sort hydrodynamically surficial sediments from the Washington margin, USA, into sand- (>250, 63-250 μm), silt- (35-63, 17-35, 8-17, 3-8μm), and clay-sized (1-3, 0.5-1, 64 μm) from the shelf, where terrestrially derived vascular plant debris accounted for >95% of the organic matter.
TL;DR: Computer simulation was used to demonstrate that relatively a small number of liposome-grafted molecules of hydrophilic and flexible polymer can create a dense protective conformational cloud over theliposome surface preventing opsonizing protein molecules from contacting liposomes.
TL;DR: The toxicity and rates of degradation for six polymers were determined, along with the toxicity of their degradation product components, and the acute toxicity of pure PGA, PLA, POE, and PCL degrade product components was determined.
Abstract: Bioabsorbable polymer implants may provide a viable alternative to metal implants for internal fracture fixation. One of the potential difficulties with absorbable implants is the possible toxicity of the polymeric degradation products especially if they accumulate and become concentrated. Accordingly, material evaluation must involve dose–response toxicity data as well as mechanical properties and degradation rates. In this study the toxicity and rates of degradation for six polymers were determined, along with the toxicity of their degradation product components. The polymers studied were poly(glycolic acid) (PGA), two samples of poly(L-lactic acid) (PLA) having different molecular weights, poly(ortho ester) (POE), poly(ϵ-caprolactone) (PCL), and poly(hydroxy butyrate valerate) (5% valerate) (PHBV). Polymeric specimens were incubated at 37°C in 0.05 M Tris buffer (pH 7.4 at 37°C) and sterile deionized water. The solutions were not changed during the incubation intervals, providing a worst-case model of the effects of accumulation of degradation products. The pH and acute toxicity of the incubation solutions and the mass loss and logarithmic viscosity number of the polymer samples were measured at 10 days, 4, 8, 12, and 16 weeks. Toxicity was measured using a bioluminescent bacteria, acute toxicity assay system. The acute toxicity of pure PGA, PLA, POE, and PCL degradation product components was also determined. Degradation products for PHBV were not tested. PGA incubation solutions were toxic at 10 days and at all following intervals. The lower molecular weight PLA incubation solutions were not toxic in buffer but were toxic by 4 weeks in water. The other materials did not produce toxic responses during the 16-week exposures. The degradation products components in order from most toxic to least toxic are: lactic acid (PLA), ϵ-caproic acid (PCL), glycolic acid (PGA), cyclohexane dimethanol (POE), propionic acid (POE), 1,6 hexane diol (POE), pentaerythritol dipropionate (POE), and pentaerythritol (POE). © 1994 John Wiley & Sons, Inc.
TL;DR: It is determined that one of the three LIM domains of zyxin is necessary and sufficient to support the association ofZyxin with CRP, and these findings demonstrate that the LIM domain functions as a specific protein-binding interface.
TL;DR: The data suggest that the mutatw phenotypes in the colorectal carcinoma cell lines could be the consequence of mutator genes affecting different repair or error-avoidance pathways.
Abstract: Recent studies have revealed that tumors in patients with hereditary nonpolyposis colon cancer are associated with high-frequency alterations of microsatellite sequences. To investigate the mechanisms and consequences of this form of genetic instability, we identified three colorectal carcinoma cell lines that express dinucleotide-repeat instability like that found in hereditary nonpolyposis colon cancer tumors and show increased rates of spontaneous mutation at selectable loci. However, the pattern of hypermutation in these cell lines differed significantly. In one line (HCT116), microsatellite mutations occurred at a remarkably high rate (approximately 10(-2) mutations per cell per generation), whereas this rate was considerably lower in the two other lines (DLD-1 and HCT15). The rate of mutation at the locus encoding hypoxanthine guanine phosphoribosyltransferase was substantially elevated (200- to 600-fold) in all three tumor cell lines, yet the types of mutations arising differed. A specific frame-shift hotspot accounted for 24% of hypoxanthine guanine phosphoribosyltransferase mutations in HCT116. The frequency of mutations at this site was reduced significantly in DLD-1 and HCT15 lines. These data suggest that the mutatw phenotypes in the colorectal carcinoma cell lines could be the consequence of mutator genes affecting different repair or error-avoidance pathways.
TL;DR: A modified version of a method that uses positive air pressures to determine the complete cavitation response of a single axis is presented in this article, where the air injection method was used to investigate variation within and amongst individuals of B. occidentalis.
Abstract: A modified version of a method that uses positive air pressures to determine the complete cavitation response of a single axis is presented. Application of the method to Betula occidentalis Hook, gave a cavitation response indistinguishable from that obtained by dehydration, thus verifying the technique and providing additional evidence that cavitation under tension occurs by air entry through interconduit pits. Incidentally, this also verified pressure-bomb estimates of xylem tension and confirmed the existence of large (i.e. >0·4 MPa) tensions in xylem, which have been questioned in recent pressure-probe studies. The air injection method was used to investigate variation within and amongst individuals of B. occidentalis. Within an individual, the average cavitation tension increased from 0·66±0·27 MPa in roots (3·9 to 10·7 mm diameter), to 1·17±0·10 MPa in trunks (12 to 16 mm diameter), to 1·36±0·04 MPa in twigs (3·9 to 5 mm diameter). Cavitation tension was negatively correlated with the hydraulically weighted mean of the vessel diameter, and was negatively correlated with the conductance of the xylem per xylem area. Native cavitation was within the range predicted from the measured cavitation response and in situ maximum xylem tensions: roots were significantly cavitated compared with minimal cavitation in trunks and twigs. Leaf turgor pressure declined to zero at the xylem tensions predicted to initiate cavitation in petiole xylem (1·5 MPa). Amongst individuals within B. occidentalis, average cavitation tension in the main axis varied from 0·90 to 1·90 MPa and showed no correlation with vessel diameter. The main axes of juveniles (2–3 years old) had significantly narrower vessel diameters than those of adults, but there was no difference in the average cavitation tension. However, juvenile xylem retained hydraulic conductance to a much higher xylem tension (3·25 MPa) than did adult xylem (2·25 MPa), which could facilitate drought survival during establishment.