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Biomedical subjects

A Walter

Publications and source records attributed to A Walter.

At least 73 records · Page 4Linked to original sources

Reversal of the Z- to B-conformation of poly(dA-dT) center dot poly(dA-dT) induced by netropsin and distamycin A.

Poly(dA-dT) center dot poly(dA-dT) which adopts the Z-form at 5 M NaCl in presence of 95 mM Ni2+ions is reversed to the B-conformation by the nonintercalating drugs netropsin (Nt) and distamycin A (Dst). The drug-induced reversal from the Z-to B-form of poly(dA-dT) center dot poly(dA-dT) is evidenced by CD spectral changes at characteristic wavelengths around 295 nm and 248 nm. The drug-induced conformational transition is accompanied by a slow kinetic process. The results suggest the preference of these AT-specific drugs for the B-form and the inability of Nt and Dst to form a stable complex with the Z-form of poly(dA-dT) center dot poly(dA-dT).

Bacterial Proteins↗

Medulloblastoma with brain stem involvement: the impact of gross total resection on outcome.

We studied the impact of gross total resection on progression-free survival (PFS) and postoperative morbidity in 40 children with locally advanced medulloblastoma characterized by tumor invading the brain stem. These patients represented 40% of children treated for newly diagnosed medulloblastoma at a pediatric oncology center over a 10-year period. All patients underwent aggressive initial surgical resection. Review of surgical and neuroimaging findings documented gross total resection in 13 cases, near-total resection (< 1.5 cm2 residual tumor on imaging) in 14 cases, and subtotal resection (> than 50% resection with > or = 1.5 cm2 residual) in 13 cases. Overall, 85% of patients had a > 90% resection. Subsequent therapy comprised craniospinal irradiation in all cases and chemotherapy on institutional or cooperative group protocols in 35 cases. At a median follow-up of 4 years, postirradiation PFS is 61% (SE = 10%). There was no difference in PFS for patients who underwent gross total resection compared to those with any detectable residual tumor (p > 0.70). The posterior fossa syndrome occurred in 25% of cases, and had no apparent relationship to the extent of resection (p > 0.5, exact test). In this series, true gross total resection was not associated with a PFS advantage when compared to strictly defined near-total and subtotal resection. Although there was no operative mortality, the frequency of the posterior fossa syndrome is of concern and emphasizes the need for careful consideration of the risk/benefit ratio in the surgical approach to this subgroup of patients.

Brain Neoplasms↗

[Agee endoscopic operation of carpal tunnel syndrome in comparison with open surgical technique].

In the course of a prospective randomised study, 120 patients underwent a carpal tunnel release procedure. The follow-up documentation included 101 patients. 54 patients had the conventional open procedure, including epineural neurolysis of the median nerve. 47 patients were treated with the Agee endoscopic procedure. The documentation included: patients age, sex, profession, duration of treatments, disablement, return to the activities of daily life (ADL) and pre- and postoperative neurological symptoms and postoperative complications. The electroneurographical measurements were performed preoperatively and nine months after operation by the same neurologist. The open and endoscopic carpal tunnel release procedures are described and the study results are reported. None of the 101 patients had wound-healing impairments. Clinical and neurological follow-up examinations did not reveal any signs of injured nerves or tendons. The study shows that the endoscopic group returned to work significantly earlier compared to the control group. At the same time, the Agee group had reduced postoperative pain symptoms. Regarding the long-term results, no significant difference between both groups was found. Based on the electrophysiological results, the study shows that epineural neurolysis of the median nerve is not necessary.

Arthroscopes↗

In vivo isoproterenol treatment leads to downregulation of the mRNA encoding the cAMP response element binding protein in the rat heart.

The expression of different myocardial regulatory proteins is altered in human heart failure, e.g., beta 1-adrenoceptors, G-proteins and others. Similar changes in rats after 4 days treatment with isoproterenol led to the hypothesis of the cAMP pathway involved in these changes. In different cell types cAMP-dependent transcriptional activation is mediated by the cAMP-response element binding protein (CREB) which was recently shown to be expressed and phosphorylated in the human heart. Here, by the reverse transcriptase-polymerase chain reaction two alternatively spliced isoforms of CREB mRNA were found to be expressed in rat ventricles. Both isoforms were down-regulated in the ventricles of rats treated in vivo with isoproterenol (2.4 mg/kg per day) for 4 days proposing a possible mechanism involved in expressional changes mentioned above.

Adrenergic beta-Agonists↗

Antiphospholipid antibody binding to bilayer-coated glass microspheres.

Thrombosis, recurrent fetal loss, and thrombocytopenia are clinical manifestations associated with circulating antibodies that recognize cardiolipin (CL)- or phosphatidylserine (PS)-dependent antigens. Enzyme-linked immunosorbent assays (ELISAs) are generally used to determine the presence and specificity of antiphospholipid antibodies (aPLs). However, the presentation of the phospholipid antigen in the ELISA assay is unknown. In this study, we determined the specificity of three mouse monoclonal aPLs for phospholipid bilayer membranes. These monoclonal aPLs had been characterized by ELISA to have different specificities for CL and PS and were designated BA3B5C4 (CL+/PS+), 3SB9b (CL-/PS+), and D11A4 (CL+/PS-). Bilayers composed of 0-100% PS or CL in phosphatidylcholine (PC) were formed on the surface of 1.6 microns diameter glass microspheres to permit analysis by flow cytometry. BA3B5C4 and 3SB9b bound specifically to both PS- and CL-containing bilayers, and binding increased with increasing percentage of anionic phospholipid. The threshold for PS-dependent binding was 20 mol% PS for both BA3B5C4 and 3SB9b. For CL-dependent binding, the threshold was below 25 mol% CL for both of these antibodies. Binding to PS-containing bilayers was tested as a function of ionic strength for BA3B5C4 and 3SB9b. The ionic strength dependence of the binding suggested that the intermolecular attractive forces between anti-PS antibodies and PS-containing bilayers are predominantly multiple weak electrostatic bonds. D11A4 bound only to bilayers composed of 100% PS and 100% PC, and this antibody did not bind to CL-containing bilayers. The binding specificities of these aPLs to bilayer membranes suggest that, in this system, the conformation of the epitope involving CL, and perhaps PS, is different from that expressed in the routine clinical ELISA. Two of the monoclonal antibodies reacted in this model system at the low levels of PS typically externalized in the plasma membranes of activated platelets, apoptopic lymphocytes, and senescent red blood cells: thus, these surfaces are plausible candidates for the site of pathologically relevant antibody interactions.

Cardiolipins↗

Neurourologic consequences of accidental intrathecal vincristine: a case report.

Inadvertent intrathecal administration of vincristine results in severe neurotoxicity. Motor and sensory bladder dysfunction have been reported but the long-term urologic consequences are unknown due to the associated high mortality. We report a case of accidental intrathecal vincristine administration with patient survival and follow-up of 24 months. The child developed a lower motor neuron neuropathic bladder requiring intermittent self-catheterization of the bladder. Urinary tract management of these children should be based on the urodynamic findings.

Child↗

Identification of estrogen regulated genes in Fe33 rat hepatoma cells by differential display polymerase chain reaction and their hormonal regulation in rat liver and uterus.

We applied the differential display RT-PCR (ddRT-PCR) technology to identify estrogen-regulated hepatic genes in the estrogen receptor expressing rat hepatoma cell line Fe33. Three genes of known sequences were detected by the ddRT-PCR approach: IGF binding protein-1 (IGFBP-1), vitamin D-dependent calcium-binding protein (CaBP9k) and major acute phase protein (MAP). Effects of ethinyl estradiol on the mRNA levels of these genes were confirmed by "Northern-blot" analysis. If given in combination with dexamethasone and glucagon, ethinyl estradiol caused 40-, 15- and 11-fold increases in the mRNA steady state level of IGFBP-1, CaBP9k and MAP, respectively, in Fe33 cells 24 h after addition of hormone. Besides ethinyl estradiol, the partial estrogen agonist OH-tamoxifen caused dose dependent effects on expression of MAP and IGFBP-1. Estrogen regulation of the respective genes and the modulatory effects of progesterone (10 mg/animal/day) were studied in ovariectomized rats treated subcutaneously for 14 days with 1 microgram/animal/day estradiol. "Northern-blot" analysis of liver RNA revealed a 6-fold stimulation of IGFBP-1 mRNA levels in estradiol-treated compared to vehicle-treated rats and a weak but detectable increase of MAP mRNA steady state level (1.6-fold) upon estradiol administration. No effect of estradiol treatment could be monitored for CaBP9k in rat liver. Modulatory effects of progesterone on estradiol-stimulated expression in the liver could be monitored for IGFBP-1 only. In an extension of our investigation on the expression of the three genes in rat liver, we determined their expression and hormonal regulation in the uterus of the same animals. In the uterus, estradiol caused an increase in CaBP9k mRNA. In contrast, IGFBP-1 mRNA levels increased dramatically upon progesterone administration, whereas no effect of estradiol treatment could be detected. MAP mRNA levels increased only after coadministration of estradiol and progesterone. In conclusion, the ddRT-PCR proved to be a powerful method to identify estrogen-regulated genes. The study on the hormonal regulation of three genes stimulated by estrogen in Fe33 cells revealed similarities and differences in their regulation in vivo and in vitro.

Acute-Phase Proteins↗

Transpapillary and transmural drainage of pancreatic pseudocysts.

BACKGROUND: Endoscopic drainage of pseudocysts using the transpapillary and transmural approaches has been reported. We evaluated endoscopic drainage in 53 patients with symptomatic pancreatic pseudocysts in whom conservative management had failed. METHODS: After preliminary endoscopic retrograde pancreatography, transpapillary drainage was attempted in 33 patients with pseudocysts that communicated with the main pancreatic duct. Transmural drainage of pseudocysts in contact with the stomach or duodenal wall was attempted in the remaining 20 patients and in 4 patients selected for combined transpapillary and transmural drainage. The cause of pseudocysts was chronic pancreatitis in 92%. The median pseudocyst size was 7.0 cm (range, 2 to 16). RESULTS: Endoscopic drainage was technically successful in 50 patients (94%), of whom 47 had complete pseudocyst resolution. Complications occurred in 11% and included gallbladder puncture (n = 1) and bleeding (n = 2) after transmural drainage, and pancreatitis (n = 1) after transpapillary drainage; stent clogging resulted in abscess formation in 2 patients. Mean follow-up was 22 months (range, 1 to 70); pseudocysts recurred in 11 patients (23%), of whom 7 were successfully re-treated endoscopically. CONCLUSION: Both transpapillary and transmural pseudocyst drainage are highly effective in patients with pseudocysts demonstrating suitable anatomy for these endoscopic techniques.

Adult↗

Stereotactic injection of herpes simplex thymidine kinase vector producer cells (PA317-G1Tk1SvNa.7) and intravenous ganciclovir for the treatment of progressive or recurrent primary supratentorial pediatric malignant brain tumors.

This study will evaluate the safety and efficacy of in vivo gene transfer of the herpes simplex thymidine kinase (HSV-Tk1) gene using PA317/G1Tk1SvNa.7 vector producer cells (VPC) in pediatric patients with progressive or recurrent primary supratentorial malignant brain tumors. Insertion of the HSV-Tk1 gene confers a sensitivity to the anti-herpes drug ganciclovir. It has been demonstrated that the direct injection of HSV-Tk vector producer cells into growing tumors in animals can result in their complete destruction with ganciclovir therapy. This selective destruction of growing tumors in situ is thought to result from the transfer of the HSV-Tk gene into the tumor cells and the production of toxic ganciclovir metabolites which result from the interaction of HSV-Tk and ganciclovir. This procedure can result in the cure of some experimental animals with limited systemic toxicity due to selective gene transfer into tumors. This clinical trial will focus on maximizing the relative number of vector producer cells to the tumor mass by stereotactically injecting VPCs into the tumor mass. Children with progressive or recurrent primary supratentorial malignant brain tumor which is accessible to stereotactic injection will be evaluated for the extent and location(s) of their disease before being entered into the study. Fifteen days after stereotactic injection of the tumor mass, ganciclovir will be administered at 5 mg/kg IV b.i.d. for 14 days. Upon completion of the treatment with HSV-Tk1 vector producer cells and ganciclovir, the patient will be followed monthly for the first three months, then every two months for the next twenty-one months, and annually for life thereafter.

Adolescent↗

Monoclonal IgM antiphosphatidylserine antibody reacts against cytoskeleton-like structures in cultured human umbilical cord endothelial cells.

PROBLEM: It has been proposed that antibodies against phospholipid-dependent antigens (aPLs), induce recurrent pregnancy loss and thrombosis through modulation of endothelial cell function, yet aPLs have not been conclusively shown to bind with endothelial cells. METHOD: Using indirect immunofluorescence we investigated the anti-endothelial cell reactivity of three monoclonal antibodies that differentiate between the phospholipids cardiolipin (CL) and phosphatidylserine (PS): BA3B5C4 (CL+/PS+); 3SB9b (CL-/PS+); and D11A4 (CL+/PS-). Cultured umbilical cord endothelial cells were prepared without fixation or with cold acetone fixation. RESULTS: None of the aPLs reacted with endothelial cells prepared without fixation. 3SB9B reacted strongly with cytoskeletal-like components in acetone-fixed cells, whereas BA3B5C4 and D11A4 were unreactive. The cytoskeletal-like binding of 3SB9b was completely blocked by a monoclonal antibody against vimentin, whereas antibodies against tubulin or actin were not inhibitory. Lipid extraction of the cells destroyed the 3SB9b reactive antigen without affecting the reactivity of anti-vimentin. CONCLUSION: These results suggest that phospholipid-dependent antigenic determinants are not expressed on the surface of resting endothelial cells but that a PS-dependent antigenic determinant is associated with endothelial cell intermediate filaments.

Animals↗

[Effect of the manufacturing process on creep and wear properties of UHMWPE (ultra-high molecular weight polyethylene)].

The creep and wear behaviour of pressed UHMWPE and extruded UHMWPE was compared, taking Chirulen and extruded UHMWPE of the Lennite type as examples. Using the ring-on-disc test, the wear and deformation volumes per 360,000 cycles were determined. The static tests were performed at surface pressures of 5.62 MPa and 9.37 MPa, while the test duration was 41.86 and 100 hours, respectively. The surface pressures result from the axial forces of 900 N and 1500 N, respectively, and a ring surface analogous to the DIN 58,835 and ISO 6474 standards. Between conventionally pressed and the extruded UHMWPE material differences of up to 350% in the sums of wear and deformation were found. It was noted that already at low surface pressures the extruded UHMWPE is more susceptible to creep deformation than is the conventionally pressed material, and that this effect dramatically increases at high surface pressures.

Biomechanical Phenomena↗

Determination of cytosolic Mg2+ activity and buffering in BC3H-1 cells with mag-fura-2.

The magnesium buffer coefficient (BMg) was calculated for BC3H-1 cells from the rise in cytosolic Mg2+ activity observed when magnesium was released from ATP after iodoacetate (IAA) and NaCN treatment. The basal cytosolic Mg2+ activity (0.54 +/- 0.1 mM) measured with mag-fura-2 doubled when 4.54 mM magnesium was liberated from ATP: BMg was 12.9 indicating that a 1 mM increase in Mg2+ activity requires an addition of about 13 mM magnesium. The accuracy of this value depends on these assumptions: (a) all of the magnesium released from ATP stayed in the cells; (b) the rise in Mg2+ was not secondary to pH-induced changes in BMg; (c) mag-fura-2 measured Mg2+ and not Ca2+; and (d) the accuracy of the mag-fura-2 calibration. Total magnesium did not change in response to IAA/CN treatment, thus the change in Mg2+ activity reflected a redistribution of cell magnesium. pH changes induced by NH4Cl pulse and removal had little effect on Mg2+ activity and the changes were slower than and opposite to pH-induced changes in Ca2+ activity measured by fura-2. Ca2+ responses were temporally uncoupled from Mg2+ responses when the cells were treated with IAA only and in no cases did Ca2+ levels rise above 1 microM, showing that the mag-fura-2 is responding to Mg2+. Additional studies demonstrated that approximately 90% of the mag-fura-2 signal was cytosolic in origin. The remaining non-diffusible mag-fura-2 either was bound to cytosolic membranes or sequestered in organelles with the fluorescence characteristics of the Mg2(+)-complexed form, even when cytosolic free Mg2+ activity was approximately 0.5 mM. This bound mag-fura-2 would appear to increase the Kd and thus clearly limits the accuracy of our estimmate for BMg. Despite this limitation, we demonstrate that Mg2+ is tightly regulated in face of large changes in extracellular Mg2+, and that interplay observed between pH, Ca2+ and Mg2+ activities strongly supports the hypothesis that these factors interact through a shared buffer capacity of the cell.

Adenosine Triphosphate↗

Cerebellar astrocytoma with extensive lipidization mimicking adipose tissue.

We report the case of an elderly woman with a history of headache, vomiting and dizziness while walking. On CT scans a mass was identified in the right cerebellar hemisphere exhibiting radiological characteristics of lipomatous tissue. Surgery revealed a compact lesion consisting of whitish-yellow tissue with a fatty aspect and texture. Smears of tissue samples and paraffin sections showed features suggestive of tissue mainly composed of fully differentiated lipocytes. Lipid-specific stainings on fresh frozen material confirmed univacuolar intracytoplasmic fat accumulation. However, immunohistochemistry for glial fibrillary acidic protein and electron microscopy clearly demonstrated the glial lineage of these lipid-laden cells. Therefore, the tumor was diagnosed as a highly lipidized astrocytoma. In our view, this case represents a variant of lipidized gliomas that has not been described previously and that differs phenotypically from the entities documented earlier.

Adipose Tissue↗

Diacylglycerol and hexadecane increase divalent cation-induced lipid mixing rates between phosphatidylserine large unilamellar vesicles.

Bovine brain phosphatidylserine (BBPS) vesicles were prepared with traces of dioleoylglycerol (18:1, 18:1 DAG) or hexadecane (HD) to determine the influence of changes in headgroup or acyl chain packing on divalent cation-induced lipid mixing rates. A stopped-flow apparatus was used to combine vesicles with 3 mM Ca2+ or Ba2+. Aggregation was monitored by light scattering and lipid mixing by lipid probe dilution. Neither 3-6 mol% 18:1, 18:1 DAG nor up to 10 mol % HD significantly altered the BBPS chain melting temperature, vesicle diameter, or vesicle aggregation rates. Lipid mixing rates doubled by adding either 3 mol % 18:1, 18:1 DAG or 6 mol % HD to BBPS with no change in the Ca2+ concentration threshold. The Arrhenius slopes of the lipid mixing rates for control, 3 mol % 18:1, 18:1 DAG, and 6 mol % HD vesicles were identical. 2H-nuclear magnetic resonance spectra of perdeuterated dipalmitoylglycerol and HD in BBPS in the absence and presence of Ca2+ and Ba2+ showed that the solutes occupied different time-averaged positions in the bilayer under each condition. These data suggest that: 1) the enhanced lipid mixing rate is related to the volume of the added alkyl chains; 2) 18:1, 18:1 DAG and HD may alter the activation entropy or the attempt frequency at one or more steps in the lipid mixing process; 3) 18:1, 18:1 DAG and HD are likely to act at a different spatial or temporal point than the divalent cation; and 4) it is unlikely that the effect of these solutes on lipid mixing is due to their equilibrium time-averaged positions in the bilayer. Others have shown that apolar lipids accelerate fusion in nonbilayer phase-forming systems, but BBPS does not form these phases under these conditions. Therefore, we propose that the effect of very small amounts of apolar substances may be very general, e.g., stabilizing the hydrophobic interstices associated with a variety of proposed intermediate structures.

Alkanes↗

Modulation of DNA supercoiling by interaction with netropsin and other minor groove binders.

The assay of DNA unwinding by ethidium, followed by sedimentation velocity techniques, was applied to complexes of supercoiled plasmid DNA with different non-intercalating drugs which strongly and sequence-specifically bind to DNA. Compared with the behaviour of naked DNA, most of the complexes exhibit an increase in the critical EB/nucleotide binding ratio associated with the principal minimum in the sedimentation profile. Using netropsin (Nt) as the paradigm of the minor groove binders investigated, the drug-induced alterations in various structural parameters of both the relaxed and supercoiled form of DNA are described. Whereas winding number, helical repeat (both being defined with reference to a surface normal), and linking number of the superhelical DNA remain constant in our experiments, its twist number, surface twist, number of superhelical turns as well as the absolute values of linking number difference, superhelix density, and writhing number increase on binding of Nt. Correspondingly, compared with the naked relaxed DNA a higher linking number (or twist number, or winding number), a higher average duplex winding angle and a lower helical repeat have to be assigned to the relaxed Nt-DNA complex. The various minor groove binders investigated were found to differ considerably in their efficiency to alter the structure of supercoiled DNA.

Base Sequence↗

Long-term results of uncemented alumina acetabular implants.

We report the clinical and tribological performance of 67 ceramic acetabular prostheses implanted between 1976 and 1979 without bone cement. They articulated with ceramic femoral heads mounted on mental femoral stems. After a mean elapsed period of 144 months, 59 sockets were radiographically stable but two showed early signs and six showed late signs of loosening. Four of the loose sockets have been revised. Histological analysis of the retrieved tissue showed a fibrous membrane around all the implants, with fibrocartilage in some. There was no bone ingrowth, and the fibrous membrane was up to 6 mm thick and infiltrated with lymphocytes, plasma cells, and macrophages. Intra- and extracellular birefringent wear particles were seen. Tribological analysis showed total wear rates in two retrieved alumina-on-alumina joints of 2.6 microns per year in a stable implant and 68 microns in a loose implant. Survival analysis showed a revision rate of 12.4% at 136 months.

Adult↗

Divalent cation-induced lipid mixing between phosphatidylserine liposomes studied by stopped-flow fluorescence measurements: effects of temperature, comparison of barium and calcium, and perturbation by DPX.

To understand the mechanism of membrane fusion, it is important to study the processes that mix the lipids of two apposed membranes. We measured the rates of divalent cation-induced aggregation and lipid mixing of bovine brain phosphatidylserine (BBPS) LUV, using light scattering and a resonance energy transfer assay. The lipid and divalent cation solutions were combined by stopped-flow mixing, which permitted measuring the half-times of aggregation and lipid mixing between pairs of liposomes. The collisional quencher DPX [p-xylene-bis(pyridinium bromide)], used in a liposome contents-mixing assay, lowered the main transition temperature (Tm) of BBPS by about 10 degrees C and decreased the temperature threshold for lipid mixing. Since DPX was inside the liposomes for the latter measurements, this implies that perturbations to the inner monolayer affect the reactivity of the liposome. When palmitoyl-oleoyl-PS (POPS) was substituted for BBPS, little or no lipid mixing occurred. Ca(2+)- and Ba(2+)-induced BBPS aggregation and lipid mixing were compared as a function of temperature and divalent cation concentration. Aggregation rates were nearly insensitive to temperature and correlated with the percent of PS bound to either Ba2+ or Ca2+. Above Tm, lipid-mixing rates increased with the Ba2+ and Ca2+ concentrations and temperature, even above the Tm of the Ba2+/PS complex. Arrhenius plots were linear for both ions. The temperature dependence was greater for Ca(2+)- than Ba(2+)-induced reactions, and the slopes were independent of divalent cation concentration. When equivalent fractions of PS were bound with divalent cation at, and above, 20 degrees C, the lipid-mixing rate was greater with Ca2+ than with Ba2+. The faster rate may reflect greater activation entropies and/or greater attempt frequencies at one or more steps in the Ca(2+)-induced process. We conclude that stopped-flow mixing permits better characterization of initial interaction between liposomes, that small changes in the acyl chain region of the PS bilayer or the inner monolayer can have large effects on lipid-mixing rates, and that the differences between Ba(2+)- and Ca(2+)-induced interactions may be related to qualitative differences in the destabilization step.

Animals↗

Final height after treatment for childhood acute lymphoblastic leukemia: comparison of no cranial irradiation with 1800 and 2400 centigrays of cranial irradiation.

We analyzed growth and final heights in 127 patients (68 female patients) treated for childhood acute lymphoblastic leukemia. Central nervous system prophylaxis included either no cranial radiation therapy (CRT) (n = 38), irradiation with 1800 centigrays (cGy) (n = 36), or irradiation with 2400 cGy (n = 53). None of the patients received spinal irradiation. Mean (+/- SEM) age at diagnosis was 6.4 +/- 0.25 years, mean height standard deviation score (SDS) at diagnosis was 0.28 +/- 0.12, and mean age at final height was 18.26 +/- 0.19 years. The change in height SDS between diagnosis and achievement of final height was significant for all treatment groups: -0.49 +/- 0.14, no CRT; -0.65 +/- 0.15, 1800 cGy; and -1.38 +/- 0.16, 2400 cGy. Irradiated patients had a greater loss in height SDS compared with the nonirradiated patients (p < 0.01), and those treated with 2400 cGy CRT had a greater decrease in final height SDS than the patients treated with 1800 cGy (p < 0.01). Both younger age and female sex were significantly associated with a greater decrease in height SDS in the patients treated with CRT; girls < or = 4 years of age at diagnosis had a mean loss in height SDS that was more than twice that observed for others treated with the same dose of CRT. Thus, although modern regimens for acute lymphoblastic leukemia (no CRT or 1800 cGy CRT) appear overall to have only a modest impact on final height, patients, especially girls, treated with 1800 cGy CRT at a young age remain at risk for clinically significant growth failure.

Age Factors↗