UFD1 contributes to MYC-mediated leukemia aggressiveness through suppression of the proapoptotic unfolded protein response.

Despite the pivotal role of MYC in tumorigenesis, the mechanisms by which it promotes cancer aggressiveness remain incompletely understood. Here, we show that MYC transcriptionally upregulates the ubiquitin fusion degradation 1 (UFD1) gene in T-cell acute lymphoblastic leukemia (T-ALL). Allelic loss of ufd1 in zebrafish induces tumor cell apoptosis and impairs MYC-driven T-ALL progression but does not affect general health. As the E2 component of an endoplasmic reticulum (ER)-associated degradation (ERAD) complex, UFD1 facilitates the elimination of misfolded/unfolded proteins from the ER. We found that UFD1 inactivation in human T-ALL cells impairs ERAD, exacerbates ER stress, and induces apoptosis. Moreover, we show that UFD1 inactivation promotes the proapoptotic unfolded protein response (UPR) mediated by protein kinase RNA-like ER kinase (PERK). This effect is demonstrated by an upregulation of PERK and its downstream effector C/EBP homologous protein (CHOP), as well as a downregulation of BCL2 and BCLxL. Indeed, CHOP inactivation or BCL2 overexpression is sufficient to rescue tumor cell apoptosis induced by UFD1 knockdown. Together, our studies identify UFD1 as a critical regulator of the ER stress response and a novel contributor to MYC-mediated leukemia aggressiveness, with implications for targeted therapy in T-ALL and likely other MYC-driven cancers.

Cardiovascular events prior to or early after diagnosis of systemic lupus erythematosus in the systemic lupus international collaborating clinics cohort.

OBJECTIVE: To describe the frequency of myocardial infarction (MI) prior to the diagnosis of systemic lupus erythematosus (SLE) and within the first 2 years of follow-up. METHODS: The systemic lupus international collaborating clinics (SLICC) atherosclerosis inception cohort enters patients within 15 months of SLE diagnosis. MIs were reported and attributed on a specialised vascular event form. MIs were confirmed by one or more of the following: abnormal ECG, typical or atypical symptoms with ECG abnormalities and elevated enzymes (≥2 times upper limit of normal), or abnormal stress test, echocardiogram, nuclear scan or angiogram. Descriptive statistics were used. RESULTS: 31 of 1848 patients who entered the cohort had an MI. Of those, 23 patients had an MI prior to SLE diagnosis or within the first 2 years of disease. Of the 23 patients studied, 60.9% were female, 78.3% were Caucasian, 8.7% black, 8.7% Hispanic and 4.3% other. The mean age at SLE diagnosis was 52.5±15.0 years. Of the 23 MIs that occurred, 16 MIs occurred at a mean of 6.1±7.0 years prior to diagnosis and 7 occurred within the first 2 years of follow-up. Risk factors associated with early MI in univariate analysis are male sex, Caucasian, older age at diagnosis, hypertension, hypercholesterolaemia, family history of MI and smoking. In multivariate analysis only age (OR=1.06 95% CI 1.03 to 1.09), hypertension (OR=5.01, 95% CI 1.38 to 18.23), hypercholesterolaemia (OR=4.43, 95% CI 1.51 to 12.99) and smoking (OR=7.50, 95% CI 2.38 to 23.57) remained significant risk factors. CONCLUSIONS: In some patients with lupus, MI may develop even before the diagnosis of SLE or shortly thereafter, suggesting that there may be a link between autoimmune inflammation and atherosclerosis.

The TCA cycle transferase DLST is important for MYC-mediated leukemogenesis.

Despite the pivotal role of MYC in the pathogenesis of T-cell acute lymphoblastic leukemia (T-ALL) and many other cancers, the mechanisms underlying MYC-mediated tumorigenesis remain inadequately understood. Here we utilized a well-characterized zebrafish model of Myc-induced T-ALL for genetic studies to identify novel genes contributing to disease onset. We found that heterozygous inactivation of a tricarboxylic acid (TCA) cycle enzyme, dihydrolipoamide S-succinyltransferase (Dlst), significantly delayed tumor onset in zebrafish without detectable effects on fish development. DLST is the E2 transferase of the α-ketoglutarate (α-KG) dehydrogenase complex (KGDHC), which converts α-KG to succinyl-CoA in the TCA cycle. RNAi knockdown of DLST led to decreased cell viability and induction of apoptosis in human T-ALL cell lines. Polar metabolomics profiling revealed that the TCA cycle was disrupted by DLST knockdown in human T-ALL cells, as demonstrated by an accumulation of α-KG and a decrease of succinyl-CoA. Addition of succinate, the downstream TCA cycle intermediate, to human T-ALL cells was sufficient to rescue defects in cell viability caused by DLST inactivation. Together, our studies uncovered an important role for DLST in MYC-mediated leukemogenesis and demonstrated the metabolic dependence of T-lymphoblasts on the TCA cycle, thus providing implications for targeted therapy.

Food safety objective approach for controlling Clostridium botulinum growth and toxin production in commercially sterile foods.

As existing technologies are refined and novel microbial inactivation technologies are developed, there is a growing need for a metric that can be used to judge equivalent levels of hazard control stringency to ensure food safety of commercially sterile foods. A food safety objective (FSO) is an output-oriented metric that designates the maximum level of a hazard (e.g., the pathogenic microorganism or toxin) tolerated in a food at the end of the food supply chain at the moment of consumption without specifying by which measures the hazard level is controlled. Using a risk-based approach, when the total outcome of controlling initial levels (H(0)), reducing levels (ΣR), and preventing an increase in levels (ΣI) is less than or equal to the target FSO, the product is considered safe. A cross-disciplinary international consortium of specialists from industry, academia, and government was organized with the objective of developing a document to illustrate the FSO approach for controlling Clostridium botulinum toxin in commercially sterile foods. This article outlines the general principles of an FSO risk management framework for controlling C. botulinum growth and toxin production in commercially sterile foods. Topics include historical approaches to establishing commercial sterility; a perspective on the establishment of an appropriate target FSO; a discussion of control of initial levels, reduction of levels, and prevention of an increase in levels of the hazard; and deterministic and stochastic examples that illustrate the impact that various control measure combinations have on the safety of well-established commercially sterile products and the ways in which variability all levels of control can heavily influence estimates in the FSO risk management framework. This risk-based framework should encourage development of innovative technologies that result in microbial safety levels equivalent to those achieved with traditional processing methods.

Quality comparison of continuous steam sterilization segmented-flow aseptic processing versus conventional canning of whole and sliced mushrooms.

UNLABELLED: This study was carried out to investigate segmented-flow aseptic processing of particle foods. A pilot-scale continuous steam sterilization unit capable of producing shelf stable aseptically processed whole and sliced mushrooms was developed. The system utilized pressurized steam as the heating medium to achieve high temperature-short time processing conditions with high and uniform heat transfer that will enable static temperature penetration studies for process development. Segmented-flow technology produced a narrower residence time distribution than pipe-flow aseptic processing; thus, whole and sliced mushrooms were processed only as long as needed to achieve the target F0 = 7.0 min and were not overcooked. Continuous steam sterilization segmented-flow aseptic processing produced shelf stable aseptically processed mushrooms of superior quality to conventionally canned mushrooms. When compared to conventionally canned mushrooms, aseptically processed yield (weight basis) increased 6.1% (SD = 2.9%) and 6.6% (SD = 2.2%), whiteness (L) improved 3.1% (SD = 1.9%) and 4.7% (SD = 0.7%), color difference (ΔE) improved 6.0% (SD = 1.3%) and 8.5% (SD = 1.5%), and texture improved 3.9% (SD = 1.7%) and 4.6% (SD = 4.2%), for whole and sliced mushrooms, respectively. Segmented-flow aseptic processing eliminated a separate blanching step, eliminated the unnecessary packaging of water and promoted the use of bag-in-box and other versatile aseptic packaging methods. PRACTICAL APPLICATION: Segmented-flow aseptic processing is capable of producing shelf stable aseptically processed particle foods of superior quality to a conventionally canned product. This unique continuous steam sterilization process eliminates the need for a separate blanching step, reduces or eliminates the need for a liquid carrier, and promotes the use of bag-in-box and other versatile aseptic packaging methods.

Plasma insulin-like growth factor-1, type 1 procollagen, and serum tumor necrosis factor alpha in children recovering from Trichuris dysentery syndrome.

OBJECTIVES: To explore: 1) the relationship between plasma insulin-like growth factor-1 (IGF-1) and other markers of growth; and 2) the effect of serum concentrations of tumor necrosis factor alpha (TNF) on growth variables in children (2-10 years) stunted by Trichuris dysentery syndrome (TDS), recovering cases, and their matched controls. METHOD: Fourteen patients with TDS were admitted to the Tropical Metabolism Research Unit, treated with albendazole and iron, and then followed with matched controls (n = 28) for 1 year. Anthropometric and biochemical measurements were done on admission and then every 3 months for the year. Plasma IGF-1, the carboxyterminal propeptide of type 1 procollagen, serum TNF, total serum protein, serum albumin, and complete blood count were determined. RESULTS: Low admission plasma levels of IGF-1 in TDS cases were accompanied by high serum levels of TNF, and total serum protein, normal serum albumin, low hemoglobin, reduced collagen synthesis (low plasma carboxyterminal propeptide of type 1 procollagen), and growth failure. These variables improved significantly after treatment. Plasma levels of IGF-1 were significantly related to the Z-scores for height-for-age (r = 0.60, 0.73, 0.68) and weight-for-age (r = 0.69, 0.80, 0.69) of cases and controls, height-for-age (r = 0.51, 0.52, 0.54) and weight-for-age (r = 0.51, 0.52, 0.54) at each measurement throughout the year. Serum levels of TNF were not related to any of the growth variables. CONCLUSION: These findings may contribute to the understanding of growth failure in children affected by other forms of chronic inflammatory bowel disease.

Standardized comparison of glucose intolerance in west African-origin populations of rural and urban Cameroon, Jamaica, and Caribbean migrants to Britain.

OBJECTIVE: To compare the prevalence of glucose intolerance in genetically similar African-origin populations within Cameroon and from Jamaica and Britain. RESEARCH DESIGN AND METHODS: Subjects studied were from rural and urban Cameroon or from Jamaica, or were Caribbean migrants, mainly Jamaican, living in Manchester, England. Sampling bases included a local census of adults aged 25-74 years in Cameroon, districts statistically representative in Jamaica, and population registers in Manchester. African-Caribbean ethnicity required three grandparents of this ethnicity. Diabetes was defined by the World Health Organization (WHO) 1985 criteria using a 75-g oral glucose tolerance test (2-h > or = 11.1 mmol/l or hypoglycemic treatment) and by the new American Diabetes Association criteria (fasting glucose > or = 7.0 mmol/l or hypoglycemic treatment). RESULTS: For men, mean BMIs were greatest in urban Cameroon and Manchester (25-27 kg/m2); in women, these were similarly high in urban Cameroon and Jamaica and highest in Manchester (27-28 kg/m2). The age-standardized diabetes prevalence using WHO criteria was 0.8% in rural Cameroon, 2.0% in urban Cameroon, 8.5% in Jamaica, and 14.6% in Manchester, with no difference between sexes (men: 1.1%, 1.0%, 6.5%, 15.3%, women: 0.5%, 2.8%, 10.6%, 14.0%), all tests for trend P < 0.001. Impaired glucose tolerance was more frequent in Jamaica. CONCLUSIONS: The transition in glucose intolerance from Cameroon to Jamaica and Britain suggests that environment determines diabetes prevalence in these populations of similar genetic origin.

Modifications in cytokeratin and actin in cultured liver cells derived from griseofulvin-fed mice.

BACKGROUND: Hepatocytes from mice fed griseofulvin (GF) for 8 months form Mallory bodies (MBs), which represent a pathologic state of intermediate filaments (IFs). The cellular mechanisms that lead to MB formation are not known. EXPERIMENTAL DESIGN: This study was aimed to investigate if MB formation could be related to modification in cytokeratin (CK) metabolism. Primary cultures of hepatocytes from control and GF livers were studied. Immunofluorescence microscopy was used to study the organization of the cytoskeleton in these cells. The hepatocytes were labeled with [35S]methionine or [32P]orthophosphate to study, respectively, the level of amino acid incorporation into IF proteins (CK 8 and CK 18) and their phosphorylation levels. The response to the tumor promoter 12-O-tetradecanoyl-phorbol-13-acetate stimulation of the phosphorylation of CK 8 and CK 18 was also elicited in contrast to control hepatocytes. RESULTS: We found that there was a change in the organization of actin and the IF network in the hepatocytes from GF-treated animals. This was associated with an increase in labeled amino acid incorporation into CK 8 and CK 18 as well as in actin. Although there was no significant difference in the absolute level of CK phosphorylation, we found modifications in the phosphorylated isomers of CK 8, the more phosphorylated isomers becoming more prominent. The treatment of the hepatocytes with 12-O-tetradecanoyl-phorbol-13-acetate did not induce changes in the level of CK phosphorylation in GF-pretreated hepatocytes. CONCLUSIONS: These results suggest that the modification of the IF network and MB formation are the consequences of increased CK synthesis and the modification of phosphorylation. They could alter the normal interaction of the IFs with different cellular components, which results in conformational changes of CKs and the reorganization of the IF network to the form of MBs.

Significance of phototherapy-induced riboflavin deficiency in the full-term neonate.

As a result of impaired fatty acid oxidation, a characteristic urinary dicarboxylic aciduria occurs in the riboflavin deficient animal. We compared the occurrence of riboflavin deficiency induced by phototherapy with changes in urinary organic acid profiles in 8 full-term, breast-fed neonates who received phototherapy for hyperbilirubinemia, and in 10 full-term, breastfed controls. Riboflavin status was assessed by measuring flavin adenine dinucleotide saturation of erythrocyte glutathione reductase. All 8 neonates exposed to phototherapy developed riboflavin deficiency (p less than 0.001). Riboflavin deficiency was progressive with the duration of phototherapy. None of the controls was riboflavin deficient. Urine organic acid profiles indicative of mitochondrial acyl-CoA dehydrogenase activity (fatty acid beta-oxidation, quantitated by gas chromatography mass spectrometry) showed no changes between the study and control groups in mono-, di-, or tricarboxylic acids or other organic acids. The riboflavin deficiency induced by phototherapy in full-term neonates was not of sufficient severity to limit riboflavin-dependent fatty acid oxidation.

Treating hypertension in black compared with white non-insulin dependent diabetics: a double blind trial of verapamil and metoprolol.

STUDY OBJECTIVE: To compare responses of blood pressure to the calcium antagonist verapamil and the beta blocker metoprolol in black compared with white diabetics with hypertension and to monitor urinary albumin excretion in relation to fall in blood pressure. DESIGN: Double blind, placebo controlled, random order crossover trial with four week placebo run in period and two six week active phases separated by a two week placebo washout period. SETTING: Outpatient department of a general hospital in a multiethnic health department. Patients--Diabetic patients with hypertension. Four dropped out before randomisation; 25 black and 14 white patients completed the trial. INTERVENTIONS: Patients given slow release verapamil 120 mg or 240 mg twice daily with placebo or metoprolol 50 mg or 100 mg twice daily with placebo. Treatment for diabetes (diet alone or with oral hypoglycaemic drugs) remained unchanged. END POINT: Comparison of changes in blood pressure in the two groups taking both drugs. MEASUREMENTS AND MAIN RESULTS: Metoprolol had little effect on blood pressure in black patients (mean fall 4.0 mm Hg systolic (95% confidence interval -2.5 to 10.4 mm Hg), 4.3 mm Hg diastolic (-0.8 to 9.5)) but more effect in white patients (mean falls 13.4 mm Hg (0.1 to 26.7) and 10.6 mm Hg (4.5 to 16.7) respectively). Verapamil was more effective in both groups, with mean falls of 8.8 mm Hg (2.4 to 15.0) and 8.1 mm Hg (5.0 to 11.2) in black patients and 19.1 mm Hg (5.4 to 32.9) and 11.4 mm Hg (0.9 to 22.0) in white patients. Heart fate fell significantly in black patients taking metoprolol, which suggested compliance with treatment. Metabolic variables were unaltered by either treatment. Plasma renin activity was low in both groups after metoprolol treatment, but change in blood pressure could not be predicted from baseline plasma renin activity. Urinary albumin:creatinine ratio was independently related to baseline blood pressure but not significantly changed by treatment. CONCLUSIONS: beta Blockers alone are not effective in treating hypertension in black diabetics. Verapamil is effective but less so than in white patients. As yet no ideal monotherapy exists for hypertension in black patients.

Treating hypertensive diabetics: a comparison of verapamil and metoprolol in black and white patients.

Ca2+ antagonists may be particularly effective in "low-renin" patients, including black subjects and diabetics, as metabolically sound antihypertensive therapy. This paper reports a double-blind randomized crossover trial of verapamil SR (to 240 mg b.i.d.) versus metoprolol (to 100 mg b.i.d.) in 20 black and 15 Caucasian non-insulin-dependent patients with entry blood pressures (BP) greater than 160/90 mm Hg. Mean age was 61 +/- 4.8 years; duration of diabetes 5.8 +/- 4.9 years. Each subject took 4 weeks placebo, then two 6 week active phases, with an intervening 2 week washout. Erect (E)/lying (L) BP, weight, and fasting blood were taken at each visit with overnight urine collections. In blacks mean entry BP (L) +/- SD were 165.8 +/- 16/98.7 +/- 11 mm Hg. On verapamil BP (L) fell significantly by -12.6 +/- 16/-6.6 +/- 9.7 mm Hg (p less than 0.01), but there was no overall fall on metoprolol (+1.65 +/- 14.5/-1.3 +/- 9.7 mm Hg). Heart rates fell on both drugs from 76.1 +/- 18.3 to 68.4 +/- 11 and 59.4 +/- 7.6 beats/min, respectively, indicating tablet compliance. In whites, BP fell on both drugs, as did heart rates. Changes in HbA1c, plasma glucose, and renin were statistically insignificant. Change in BP was unrelated to initial renin levels in either blacks or whites. In blacks, mean entry urine Na, K, and Ca were 77.4 +/- 39.3, 20.9 +/- 10, and 2.35 +/- 1.5 mmol/l and in whites 84.1 +/- 42, 22 +/- 17.2, and 3.56 +/- 3.2 mmol/l, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

Renal metabolism of glutamine in rats with acute renal failure.

Acute renal failure induced by glycerol results in increased metabolism of glutamine by renal cortical slices of rats 16 and 36 hr after onset, and there is also increased glutamine uptake by the kidney in vivo. Metabolism of glutamine and glutamate to glucose is inhibited. At 8 days after onset of renal failure, metabolism of glutamine returns to normal. Initially, activities of phosphate-dependent glutaminase (PDG) and glutamate dehydrogenase are depressed. The activity of glutaminase returns to normal by 8 days, but glutamate dehydrogenase activity is still inhibited. Increased ammoniagenesis and glutamine uptake are mainly a result of increased entry into the cell since activity of glutaminase is inhibited.

Effect of temperature on optical density of rabbit blood in dye dilution studies.

The optical desity of rabbit blood increased on cooling. This increase was additive to the deflection produced by indocyanine green at all concentrations measured. If calibration curves were not corrected for any increase in optical density produced by cooling the blood, and error (minimum 11%) was introduced in the estimation of cardiac output. The effect of temperature was investigated with three different densitometers. Its wave-length dependence did not follow the absorption spectrum of oxyhemoglobin.