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T Turi

Publications and source records attributed to T Turi.

9 recordsLinked to original sources
PubMed2000

High density lipoprotein deficiency and foam cell accumulation in mice with targeted disruption of ATP-binding cassette transporter-1.

Recently, the human ATP-binding cassette transporter-1 (ABC1) gene has been demonstrated to be mutated in patients with Tangier disease. To investigate the role of the ABC1 protein in an experimental in vivo model, we used gene targeting in DBA-1J embryonic stem cells to produce an ABC1-deficient mouse. Expression of the murine Abc1 gene was ablated by using a nonisogenic targeting construct that deletes six exons coding for the first nucleotide-binding fold. Lipid profiles from Abc1 knockout (-/-) mice revealed an approximately 70% reduction in cholesterol, markedly reduced plasma phospholipids, and an almost complete lack of high density lipoproteins (HDL) when compared with wild-type littermates (+/+). Fractionation of lipoproteins by FPLC demonstrated dramatic alterations in HDL cholesterol (HDL-C), including the near absence of apolipoprotein AI. Low density lipoprotein (LDL) cholesterol (LDL-C) and apolipoprotein B were also significantly reduced in +/- and -/- compared with their littermate controls. The inactivation of the Abc1 gene led to an increase in the absorption of cholesterol in mice fed a chow or a high-fat and -cholesterol diet. Histopathologic examination of Abc1-/- mice at ages 7, 12, and 18 mo demonstrated a striking accumulation of lipid-laden macrophages and type II pneumocytes in the lungs. Taken together, these findings demonstrate that Abc1-/- mice display pathophysiologic hallmarks similar to human Tangier disease and highlight the capacity of ABC1 transporters to participate in the regulation of dietary cholesterol absorption.

ATP Binding Cassette Transporter 1↗
PubMed1997

Molecular cloning of a peptidase against N-acetylaspartylglutamate from a rat hippocampal cDNA library.

N-Acetylaspartylglutamate (NAAG) is the most prevalent peptide neurotransmitter in the mammalian nervous system. NAAG selectively activates the type 3 metabotropic glutamate receptor. It is inactivated by peptidase activity on the extracellular face of the plasma membrane of neurons and glia. The human gene that codes for prostate-specific membrane antigen (PSM) has been shown to produce peptidase activity against NAAG. We cloned the human PSM cDNA and used it to probe a rat hippocampal cDNA library. We identified a cDNA containing a complete coding region that possesses 83% homology with the PSM gene. The predicted 752-amino acid sequence has 85% identity and 91% similarity to the PSM sequence. CHO cells transfected with this cDNA expressed NAAG peptidase activity at a level similar to that obtained from rat brain membranes. The peptidase activity was inhibited by beta-NAAG, quisqualate, and pteroylglutamate but not aspartylglutamate or pteroic acid. In situ hybridization data demonstrated the widespread distribution of the peptidase mRNA in the brain, consistent with the distribution of peptidase activity. The highest levels of hybridization were detected in the hippocampus, dentate gyrus, piriform cortex, choroid plexus of the ventricles, pineal gland, anterior pituitary, and supraoptic nucleus. Three transcripts (estimated at 5, 3.4, and 2.9 kb) were identified in northern blots of rat brain, while in rat kidney the third transcript appeared slightly smaller than 2.9 kb. With use of reverse transcriptase PCR with primers for the 5' end, the central region, and the 3' end of the hippocampal cDNA, the expected amplification products were obtained from rat brain RNA. Spinal cord yielded an amplification product only with primers for the 5' end of the hippocampal cDNA.

Amino Acid Sequence↗
PubMed1994

The natural history of postischemic T-wave inversion: a predictor of poor short-term prognosis?

BACKGROUND: This study followed up the natural history of T-wave inversion and assessed the short-term prognosis associated with the condition. METHODS: Forty patients with acute ischemic syndrome, without infarction, and with postischemic T-wave inversion (group 1) were followed during the persistence (inverted T-wave period) and after the resolution of T-wave inversion (positive T-wave period). Another 40 patients with acute ischemic syndrome, without infarction and with normal T waves (group 2), were also followed. RESULTS: Postischemic inverted T waves showed resolution within 3-21 days of presentation in 31 patients from group 1 on medical treatment alone. Further ischemic events (acute myocardial infarction, acute ischemic syndrome, angina pectoris, silent ischemia), inducible ischemia (during treadmill test), wall-motion abnormalities (demonstrated by echocardiography), all developing in the primarily ischemic myocardial area, were more frequent (P < 0.02) in group 1 patients during the inverted T-wave period compared with those experienced in the positive T-wave period of group 1 patients, and compared with group 2 patients. CONCLUSION: In most patients on medical treatment, postischemic inverted T-waves tended to resolve within 3 weeks. The presence of postischemic inverted T waves appears to be an independent marker of further ischemic events.

Adult↗
PubMed1993

[Postischemic inverted T waves: does gradual regression indicate improved prognosis?].

This study has followed up the natural history of postischemic inverted T waves and assessed the prognosis. 40 consecutive patients with unstable angina with postischemic precordial inverted T waves in the noninfarcted, previously ischemic area were followed during the persistence (negative T wave period) and after resolution of inverted T waves (positive T wave period). The outcome with frequencies of acute myocardial infarction, acute ischemic syndrome, angina pectoris, positive exercise test, silent myocardial ischemia, anterior wall motion abnormalities on echocardiogram, positive coronary arteriography were determined and compared in the negative versus positive T wave periods. Postischemic inverted T waves showed resolution within the postischemic 3-21 days (at a mean of 10.6 days) in 31 patients on medical treatment alone during the whole study period. Frequencies of parameters/patients determined in negative versus positive T wave periods are as follows: acute myocardial infarction: 5/40 versus 0/31 (non significant), acute ischemic syndrome: 25/40 versus 2/31 (p < 0.001), angina pectoris: 32/40 versus 11/31 (p < 0.001), positive treadmill exercise test: 14/16 versus 14/30 (p < 0.02), silent myocardial ischemia: 14/14 versus 16/31 (p < 0.01), hypokinesis 26/34 versus 4/24 (p < 0.001), positive coronary arteriography: 4/4 versus 11/11 (non significant). In most patients on medical treatment, the postischemic inverted T waves tend to resolve within 3 weeks. Attention has to be paid to the patients with postischemic inverted T waves during the negative T wave period: the high ischemic risk gradually decreases with resolution of negative T waves.

Angina, Unstable↗
PubMed1993

Sterol synthesis and viability of erg11 (cytochrome P450 lanosterol demethylase) mutations in Saccharomyces cerevisiae and Candida albicans.

The identification of the precise structural features of yeast sterol molecules required for the essential "sparking" function has been a controversial area of research. Recent cloning and gene disruption studies in Saccharomyces cerevisiae have shown that C-24 methylation (ERG6), C-5 desaturation (ERG3) and delta 8-delta 7 isomerization (ERG2) are not required, while C-14 demethylation (ERG11) and C-14 reduction (ERG24) are each required for aerobic viability. Earlier observations had indicated that C-14 demethylase deficient strains could be restored to aerobic growth by suppressor mutations that caused a deficiency in C-5 desaturase. These strains were reported to synthesize some ergosterol, indicating that they contained leaky mutations in both ERG11 and ERG3, thereby making it impossible to determine whether the removal of the C-14 methyl group was required for aerobic viability. The availability of the ERG11 and ERG3 genes has been used in this study to construct strains that contain null mutants in both ERG11 and ERG3. Results show that these double disruption strains are viable and that spontaneously arising suppressors of the ERG11 disruption are erg3 mutants. The erg11 mutants of S. cerevisiae are compared to similar mutants of Candida albicans that are viable in the absence of the erg3 lesion.

Aerobiosis↗
PubMed1991

[Significance of the ECG in the diagnosis of so-called "stunned myocardium"].

The common feature of these 3 case reports can be characterized by the negative symmetric giant T waves developing 1-2 days after an acute myocardial ischemic attack, producing no enzymatic evidence of necrosis, persisting for several days or some weeks. The negative transient T waves are considered to fulfil neither the classical electrocardiographic characteristics of acute or chronic myocardial ischemia nor the criteria of subendocardial necrosis, but are believed to designate the existence of myocardial stunning. The authors suggest, that transient Q waves having been declared as the only electrocardiographic marker of myocardial stunning, reflect severe "transmural stunning" and can be detected relatively rarely, for a short time. In contrast, the transient negative T waves reflect "subendocardial stunning" and can be documented more frequently, persist for a longer time, and therefore could be a simple and sensitive method in detection of myocardial stunning.

Adult↗
PubMed1990

[A case of surgically treated septum perforation associated with acute myocardial infarct].

The authors present the case-history of an elderly female patient with acute myocardial infarction complicated by ventricular septal defect (VSD). She was operated on in order the VSD to be corrected but--probably because of sutural insufficiency--it temporarily reopened, later closed spontaneously. The significance of certain tests in the differential diagnosis of systolic murmur after acute myocardial infarction is discussed, and the importance of these findings compared to the clinical picture is emphasized.

Aged↗
PubMed1989

[ECG characteristics of acute myocardial ischemia].

UNLABELLED: The authors discussed the efficacy of ECG in distinction of reversible and irreversible myocardial damage. On the basis of continuous ECG monitoring of a patient, suffering from acute ischemic syndrome, it was established, that neither the appearance of R wave reduction nor that of the transient Q wave (besides the widely accepted ST segment elevation) do not signify the fact of transmural myocardial infarction. IN CONCLUSION: the classical rules in indication of myocardial rescue therapy should be expanded and ECG monitoring is of crucial importance in indication and evaluation of myocardial rescue therapy in acute myocardial ischemic syndrome.

Electrocardiography↗