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A factor analysis of dyspnea indexes and lung function parameters in patients with chronic obstructive pulmonary disease.

The purpose of the present study was to investigate the correlation between dyspnea ratings and a large group of lung function parameters, and extract those factors that best reflect the functional profile of patients with COPD using factor analysis. Ninety nine patients with COPD in stable clinical condition (age 60 +/- 8 years, ATS score = 2.5 +/- 0.9, FEV1% pred. = 33 +/- 13%) were included in the study. The factor analysis of the results yielded 5 factors which accounted for 80.1% of the total variance of the changes. The highest coefficients found between the factors and the original group of variables after Varimax rotation are given in the following table: Factor 1: Oxygen-cost diagram: 0.92; ATS dyspnea score: -0.80; TL,CO/VA: 0.78; Factor 2: FEV1% pred.: 0.87; FEV1/VC%: 0.86; FEV1L: 0.79; Factor 3: MIF50% pred.: 0.85; FIV1% pred.: 0.76; PImax: 0.67; Factor 4: PaCO2: -0.81; SaO2: 0.77; Mean pulmonary arterial pressure: -0.67 Factor 5: Age: 0.88; Six minutes walk distance: -0.72 The factor analysis showed that the functional profile of COPD patients has several dimensions. Therefore, in order to have COPD comprehensively evaluated, assessment of dyspnea and the respective set of lung function parameters (exercise capacity, forced inspiration and pulmonary hemodynamics), should be included in the battery of tests, besides the conventional tests.

Dyspnea↗

Comparison of two catheter withdrawal speeds during simultaneous urethral pressure profilometry in anesthetized bitches.

Maximal urethral closure pressure, functional profile length, and number of respiratory peaks on the resting urethral pressure profile, expressed as a percentage of those occurring on the bladder pressure recording, were compared at catheter withdrawal speeds of 1 and 3 mm/s in 30 anesthetized bitches. Significant (P less than 0.001) differences were found in maximal urethral closure pressure and percentage of transmission of respiratory peaks between the 2 speeds. Significant difference was not detected in functional profile length.

Animals↗

Cross-species phenotypic profiling uncovers functional determinants of bacterial cold shock adaptation.

Temperature shifts impose broad physiological stress, requiring precise and dynamic regulatory programs to restore cellular homeostasis. While the heat shock response is well characterized, the mechanisms underlying cold shock response (CSR) remain less understood. To identify genes critical for cold adaptation, we applied transposon sequencing (Tn-seq) to monitor mutant fitness across the full course of CSR and sustained low-temperature growth in two mesophilic bacteria, Escherichia coli and Bacillus subtilis. In B. subtilis, phenotypic profiling revealed a temporally structured program: membrane fluidity and cell wall remodeling were most critical in the early stage of CSR, whereas post-transcriptional regulation became essential during late-stage recovery to reprogram gene expression and restore growth. Cross-species comparison uncovered both conserved and species-specific mechanisms, with RNA metabolism and ribosome/translation regulators playing broad roles. Specifically, we identified a conserved synergy between two ribosomal RNA methyltransferases, RsmA and RsmH, in promoting cold adaptation. In B. subtilis, mutants lacking these enzymes exhibited significant delay in translation recovery following cold-induced global inhibition. Together, these findings provide a comparative, systems-level view of bacterial cold adaptation and establish a framework for exploring stress responses in pathogens and extremophiles.

Cell envelope↗

Molecular cloning, gene structure, expression profile and functional characterization of the mouse glutamate transporter (EAAT3) interacting protein GTRAP3-18.

Glutamate is an important amino acid implicated in energy metabolism, protein biosynthesis and neurotransmission. The Na(+)-dependent high-affinity excitatory amino acid transporter EAAT3 (EAAC1) facilitates glutamate uptake into most cells. Recently, a novel rat EAAT3-interacting protein called GTRAP3-18 has been identified by a yeast two-hybrid screening. GTRAP3-18 functions as a negative modulator of EAAT3-mediated glutamate transport. In order to further understand the function and regulation of GTRAP3-18, we cloned the mouse orthologue to GTRAP3-18 and determined its gene structure and its expression pattern. GTRAP3-18 encodes a 188-residue hydrophobic protein whose sequence is highly conserved amongst vertebrates. Mouse and human GTRAP3-18 genes contain three exons separated by two introns. The GTRAP3-18 gene is found on mouse chromosome 6D3 and on human chromosome 3p14, a susceptibility locus for cancer and epilepsy. GTRAP3-18 protein and RNA were found both in neuronal rich regions of the brain and in non-neuronal tissues such as the kidney, heart and skeletal muscle. Mouse GTRAP3-18 inhibited EAAT3-mediated glutamate transport in a dose-dependent manner. These studies show that GTRAP3-18 is a ubiquitously expressed protein that functions as a negative regulator of EAAT3 function.

Amino Acid Sequence↗

Phenotypic profile and functions of T cell receptor-gamma delta-bearing cells from patients with primary immunodeficiency syndrome.

TCR-gamma delta-bearing T cells have been reported to be increased in several immunodeficient patients. However, their functional role and phenotypic characterization have not yet been well documented. In this study we examined the surface phenotypes and functional properties of TCR-gamma delta+ cells from several patients with primary immunodeficiency syndrome. It was demonstrated that TCR-gamma delta+ cells detected by TCR-delta 1 mAb were increased in some of the patients, particularly in patients with Wiskott-Aldrich syndrome and severe combined immune deficiency. The TCR-gamma delta+ cells showed such a unique profile that more than 60% of the cells expressed delta-TCS1, which is normally present in a lesser amount, and that most of the cells lacked CD5 T lineage marker. TCR-gamma delta+ cells from the patients with primary immunodeficiency syndrome served as NK cells as observed in normal individuals, while displaying weak LAK and allogeneic cell-specific killer activities. The TCR-gamma delta+ cells were classified into several subpopulations according to their antigenic phenotype, then their NK activity of normal individuals and patients, lymphokine-activated killer and allo-specific killer activities of normal individuals were compared among the subpopulations. Delta-TCS1+ cells mediated almost the same killer activities as total TCR-gamma delta+ cells, whereas CD8+ TCR-gamma delta+ cells displayed stronger cytotoxic activities in both normal subjects and the patients with primary immunodeficiency syndrome.

Antibodies, Monoclonal↗

Human thyroid fibroblasts exhibit a distinctive phenotype in culture: characteristic ganglioside profile and functional CD40 expression.

Fibroblasts from different regions of the human body exhibit substantial phenotypic diversity, some of which relates to the capacity for cross-talk with cells of the immune system. We examine, for the first time, thyroid fibroblast biology in culture. Thyroid explants were placed in culture, and fibroblasts were outgrown and serially passaged. These fibroblasts take on a morphology in culture resembling cells from other anatomic regions. When treated with PGE2, they assume a stellate morphology similar to that of prostanoid-treated orbital fibroblasts. The ganglioside profile exhibited by these cells is distinct from that observed previously in orbital and dermal fibroblasts. They uniformly express Thy-1, a surface glycoprotein. Messenger RNA encoding CD40, a surface receptor found on bone marrow-derived cells, and CD40 protein were expressed constitutively at low levels. Interferon-gamma (500 U/ml) treatment for 48-72 h resulted in high levels of surface HLA-DR and CD40 display. When CD40 is engaged with CD40 ligand (CD40L), nuclear factor-kappaB binding activity is up-regulated as is interleukin (IL)-6 and IL-8 expression. IL-1beta treatment up-regulates the expression of IL-1alpha, IL-1beta, and PGE2. These observations suggest that thyroid fibroblasts possess the molecular machinery necessary for cross-talk with immunocompetent cells such as lymphocytes and mast cells through the CD40/CD40L complex, as well as through classic cytokine networks, and to participate potentially in the inflammatory response of the thyroid gland.

CD40 Antigens↗

Use of fine-wire electrodes for electromyographic evaluation of the external urethral sphincter during urethral pressure profilometry in male cats.

Evaluation of urethral pressure profilometry (UPP) with simultaneous fine-wire electromyography of the external urethral sphincter (EUS) was conducted in 11 healthy adult male cats sedated with xylazine and ketamine. A 3.5-F urethral catheter with a closed end and two 1-mm side-ports was infused with sterile 0.9% NaCl solution at a rate of 2 to 3 ml/min. A fine-wire electromyographic (EMG) electrode was placed percutaneously into or near the external urethral sphincter prior to the onset of the UPP. The maximal urethral pressure achieved and functional profile length were recorded from UPP. Setting both catheter withdrawal rate and paper speed at 5 mm/s enabled the measurement of actual urethral length directly from UPP. Sphincter EMG activity was rated as slight (+), moderate (+ +), or intense (+ + +). All recordings were replicated once during each trial for 8 cats and trials were replicated 5 to 7 days later in 4 cats. Before catheterization, EMG activity of the external urethral sphincter was rated slight (+), whereas intense (+ + +) activity accompanied insertion. The activity evoked by movement of the catheter subsided, but intense EMG activity of the external urethral sphincter was recorded from onset to completion of catheter withdrawal in all cats in both trials. The mean maximal urethral pressure was 93.1 +/- 13.29 cm H2O. The mean function urethral length was 8.1 +/- 0.93 cm. Maximal urethral pressure or function profile length did not differ significantly between recordings within trials or between trials. Simultaneous recording of EMG activity and UPP of the external urethral sphincter was shown to be a simple, noninvasive technique for assessing neuromuscular and anatomic urethral function.

Animals↗

Transplantation of allogeneic islets of Langerhans in the rat liver: effects of macrophage depletion on graft survival and microenvironment activation.

Early impairment of islet function and graft loss limit the success of allogeneic islet transplantation. Nonspecific inflammatory events occurring at the transplant site immediately after grafting, involving the production of cytokines and free radicals and sinusoidal endothelial cell (SEC) activation, may contribute to islet cell damage. To evaluate whether Kupffer cell inactivation would result in prolonged allograft survival in a model system of intrahepatic islet transplantation in rats, we systemically administered either gadolinium chloride (GdCl3) or dichloromethylene diphosphonate (Cl2MDP) to assess the effects of macrophage inactivation on rejection and on the release of proinflammatory molecules, as well as to assess the functional profile of SEC. The results obtained were compared with those observed in untreated, sham-injected animals and in rats receiving intraportal infusions of microbeads. Transient macrophage inhibition, particularly in hepatic Kupffer cells, is associated with significant prolongation of graft survival after intraportal islet allotransplantation (ITx) in rats: 7.2 days in the control group versus 11.9 days in the GdCl3 group (P < 0.01) and 15.6 days in the Cl2MDP group (P < 0.0006), respectively. Although systemic release of inflammatory mediators was observed only when islet transplantations were performed and it could be inhibited by macrophage-targeting treatments, perturbation of the functional profile of endothelial cells was also observed when microembolization was induced by the use of microbeads and could not be prevented by macrophage inhibition. These experiments provide evidence to support the concept that macrophages play a key role in early inflammatory events known to adversely affect islet engraftment and suggest that manipulation of nonspecific immune activation by inhibition of macrophage function may facilitate hepatic engraftment of islet allografts. The mechanisms mediating this effect are likely to include prevention of release of tumor necrosis factor-alpha, interleukin-1beta, and NO and interference with the rate of immune response to the islets.

Animals↗

T cells expressing the gammadelta receptor are essential for Th2-mediated inflammation in patients with acute exacerbation of asthma.

OBJECTIVE: T lymphocytes have a central regulatory role in the pathogenesis of asthma. The objective of this study was to characterize immunologically the activation stage of asthma and the functional profile of lymphocytes from induced sputum, with particular emphasis on gammadelta T cells. METHODS: Induced sputum was collected from 10 patients with acute exacerbation of asthma, and from healthy controls. The expression of activation markers on freshly isolated induced sputum lymphocytes and T-cell subsets was analyzed by double immunofluorescent staining and flow cytometry. Fas ligand (FasL) was determined by reverse transcriptase-polymerase chain reaction analysis. The phenotype of gammadelta T-cell subpopulations was tested by A13 and BB3 monoclonal antibodies. In this context, the functional profile of gammadelta T cells was tested in a chromium releasing test. RESULTS: A significantly decreased proportion of alphabeta T cells and an increased proportion of gammadelta T cells, CD56+ cells and CD8+ gammadelta T cells were found in asthma patients compared with healthy controls. In asthmatic patients, there is a significantly increased proportion of T cells expressing CD69 and CD25 antigen. After stimulation of gammadelta T cells, an increased expression of intracellular tumour necrosis factor-alpha, interleukin (IL)-4 and IL10 cytokines were found at higher levels than controls. Interferon-gamma was observed at similar levels in asthma patients and healthy controls. Freshly isolated T-cell receptor (TCR) gammadelta+ cells exhibited an increased percentage of FasL in our patient group. FasL mRNA was detected in TCR gammadelta+ cells before and after IL2 stimulation. TCR gammadelta+ cells were cytotoxic against the K562 cell line. This natural killer activity was mediated by the A13-positive subpopulation. CONCLUSION: The presence of cytokines producing gammadelta cells in induced sputum of asthmatic patients is consistent with regulatory activities. These cells display also cytotoxic function.

Acute Disease↗

[Effects of prophylactic intraportal chemotherapy on liver function, blood profile and survival in patients with colo-rectal cancer].

Postoperative intraportal anti-cancer chemotherapy was used for 51 patients with curatively resected colorectal cancer who were selected in the randomized controlled study to evaluate its inhibitory effect on liver metastasis from colo-rectal cancer. In cases of intraportal chemotherapy, 30 mg of Mitomycin-C (in 3 doses) and 5 mg/kg (B.W.)/day (1985-1986) or 3 mg/kg/day (1987-1988) of 5-FU was injected through the catheter inserted into the portal vein during postoperative 14 days. In cases of the control group (58 patients), the same doses of the drugs were injected into the peripheral vein during the same term. Six patients with recurrences were observed in the intraportal chemotherapy group, and 3 of them had liver metastases. In the control group, more liver metastases were observed (5 of 7 recurrences were liver metastases). Intraportally injected 5 mg/kg/day of 5-FU slightly disturbed the liver function. The averages of the serum GOT, GPT and gamma-GTP level of these cases were higher than those of the control cases. Three mg/kg/day of intraportally injected 5-FU had no influence on the liver function. There were no differences in the incidence of leukocytopenia or thrombocytopenia between the two groups.

Aged↗

The significance of spontaneous hepatitis B e antigen seroconversion in childhood: with special emphasis on the clearance of hepatitis B e antigen before 3 years of age.

To investigate the significance of spontaneous hepatitis B e antigen (HBeAg) seroconversion during childhood, 415 hepatitis B surface antigen (HBsAg) carrier children (ages 0 to 15 years) were prospectively followed for 7.1 +/- 2.9 years. Hepatitis B virus (HBV) markers and liver function profiles of each child were tested at least once every 6 months. Among them, 50 were initially anti-HBe positive and 140 seroconverted from HBeAg to anti-HBe during follow-up. Before HBeAg seroconversion, jaundice occurred in 9 and alanine transaminase (ALT) activities elevated in 99 of the 140 seroconverters. Serum ALT returned to normal in all patients within 1 to 5 years of seroconversion. Six had reelevated ALT later after seroconversion. Only 7 (9.7%) of the 72 carrier infants seroconverted before 3 years of age. The peak ALT levels in five of them exceeded 100 IU/L, and two had jaundice before HBeAg seroconversion. One of the early seroconverters developed hepatocellular carcinoma (HCC) at 11 years of age, although his liver function profiles remained normal after HBeAg seroconversion. Liver biopsy specimens from 30 children during the anti-HBe-positive stag e showed inactive cirrhosis in 2 (including one with HCC), chronic hepatitis with marked fibrosis in 1, mild activity and moderate fibrosis in 2, mild activity and mild fibrosis in 9, and minimal histologic changes in the remaining 16. Although most will achieve a normalization of ALT and inactive liver histologic changes, the seroconversion of HBsAg carrier children from HBeAg to anti-HBe is not necessarily an indicator of favorable prognosis; a small proportion of children will develop cirrhosis or even HCC.

Adolescent↗

Agonists and antagonists acting at P2X receptors: selectivity profiles and functional implications.

P2X receptors are nucleotide-gated cation channels composed of homomeric or heteromeric assemblies of three subunits. In the past 7 years, an extended series (P2X1-7) of P2X subunits has been cloned from vertebrate tissues. In this rapidly expanding field, one of the main current challenges is to relate the cloned P2X receptor subtypes to the diverse physiological responses mediated by the native P2X receptors. However, the paucity of useful ligands, especially subtype-selective agonists and antagonists as well as radioligands, acts as a considerable impediment to progress. Most of the ligands available are highly limited in terms of their kinetics of action, receptor-affinity, subtype-selectivity and P2X receptor-specificity. Their suspected ability to be a substrate for ecto-nucleotidases or to inhibit these enzymes also complicates their use. A number of new antagonists at P2X receptors have recently been described which to some degree are more potent and more selective than earlier antagonists like suramin or pyridoxal-5'-phosphate-6-azophenyl 2',4'-disulfonate (PPADS). This work moves us closer to the ideal goal of classifying the recombinant and native P2X receptor subtypes on the basis of antagonist profiles. This review begins with a brief account of the current status of P2X receptors. It then focuses on the pharmacological properties of a series of key P2 receptor agonists and antagonists and will finish with the discussion of some related therapeutic possibilities.

Animals↗

Stimulation by antipsychotic agents of mitogen-activated protein kinase (MAPK) coupled to cloned, human (h)serotonin (5-HT)(1A) receptors.

RATIONALE: There is evidence that serotonergic mechanisms contribute to the functional profiles of antipsychotic drugs, several of which display affinity for human (h)5-HT(1A) receptors. OBJECTIVE: Here, we compared the interaction of several antipsychotic agents at h5-HT(1A) receptors employing mitogen-activated protein kinase (MAPK), an intracellular marker. METHODS: The influence of antipsychotics on MAPK phosphorylation was quantified in Chinese hamster ovary (CHO) cells stably transfected with h5-HT(1A) receptors by use of a highly selective antibody. RESULTS: The novel antipsychotic agent, S16924, concentration-dependently (pEC(50), 8.10) stimulated the phosphorylation of MAPK. Its maximal effect (96%) was similar to that of the prototypical 5-HT(1A) agonist, (+)8-OH-DPAT (pEC(50), 8.54) (defined as 100%). The selective 5-HT(1A) receptor antagonist WAY100,635, which was inactive alone, abolished stimulation of MAPK by S16924 with a pK(b) of 9.66. This stimulatory influence of S16924 on MAPK was potently mimicked by the benzoisoxazole, antipsychotic ziprasidone (pEC(50), 7.25; 93%). The atypical antipsychotic clozapine also activated MAPK, albeit with lower potency and efficacy (pEC(50), 5.43 and 43%). These actions of ziprasidone and clozapine were also blocked by WAY100,635. Evaluated at a single, high concentration, several other antipsychotics stimulated MAPK phosphorylation with variable efficacy: quetiapine (75%), ocaperidone (74%), tiospirone (57%), olanzapine (54%) and risperidone (21%). In all cases, their actions were abolished by WAY100,635. In contrast, haloperidol, thioridazine and sertindole did not stimulate MAPK. CONCLUSIONS: Antipsychotics display contrasting efficacies in modulating MAPK phosphorylation at h5-HT(1A) receptors, ranging from high (e.g. S16924 and ziprasidone), via intermediate (e.g. clozapine) to low (e.g. haloperidol). Differential modulation of 5-HT(1A) receptor-coupled MAPK may contribute to their contrasting functional profiles.

Animals↗

Arrhythmic profile, ventricular function, and histomorphometric findings in patients with idiopathic ventricular tachycardia and mitral valve prolapse: clinical and prognostic evaluation.

BACKGROUND: In patients with ventricular tachycardia (VT) and apparently normal hearts, mitral valve prolapse (MVP) is discovered fairly often, raising the question of whether or not it is an occasional finding. HYPOTHESIS: This issue was analyzed in a series of patients with VT and apparently normal hearts in order to define the prevalence of MVP in this condition, the existence of specific diagnostic features suggesting a nonrandom association between idiopathic VT and MVP, and the prognostic implications of this finding. METHODS: We studied 28 consecutive patients with documented VT and no history of heart disease. Two-dimensional (2-D) echocardiogram, cardiac catheterization, morphometric examination of endomyocardial biopsy and arrhythmologic evaluation (24-h Holter monitoring, electrophysiologic study, and signal-averaged electrocardiogram) were performed. Inclusion criteria for all patients were angiographically normal coronary arteries, normal biventricular function, and absence of histologic evidence of myocarditis. Data obtained in patients found to have MVP at 2-D echo were compared with those of the remaining patients. Long-term follow-up data were also collected. RESULTS: The prevalence of MVP in our study group was 25% (7 patients). It was not associated with leaflet dysplasia or significant regurgitation. Biventricular function (ventricular volumes and ejection fraction) was comparable in patients with and without MVP. Patients with MVP had a significantly higher prevalence of ventricular late potentials at signal-averaged electrocardiogram (86 vs. 29%, p = 0.027), more interstitial fibrosis at morphometry (8.5 +/- 3.7 vs. 5.4 +/- 2.7% p = 0.028), and VT of right bundle-branch block morphology (100 vs. 48%; p = 0.044). Other arrhythmologic findings were similar in the two groups. After a mean follow-up of > 5 years, no patient in either group died, and none developed heart failure or severe mitral regurgitation. CONCLUSIONS: Mitral valve prolapse is frequently detected in idiopathic VT. The distinguishing features of this association are (1) VT of right bundle-branch block morphology, (2) high prevalence of ventricular late potentials, and (3) increased fibrosis on endomyocardial biopsy. Ventricular function and other arrhythmologic findings are not specific of this association. Prognosis remains substantially benign, as is true for most cases of idiopathic VT.

Adolescent↗

Dietary Polyphenol Acteoside-Related Molecular Signatures in Clear Cell Renal Cell Carcinoma: Multi-Omics Profiling and Functional Validation of IMPDH1.

Clear cell renal cell carcinoma (ccRCC) is characterized by substantial metabolic and molecular heterogeneity, but the disease-relevant programs associated with acteoside, a dietary polyphenol, remain poorly understood. We integrated predicted acteoside targets with bulk, single-cell, and spatial transcriptomic data from ccRCC and combined molecular subtyping with cross-cohort machine-learning analysis. Acteoside-related signatures were preferentially enriched in malignant compartments and increased with tumor grade and stage. Consensus clustering identified two molecular subtypes with distinct biological and clinical features. C1 was associated with immune activation, metabolic activity, and more favorable survival, whereas C2 showed greater genomic instability, reduced renal epithelial differentiation, and poorer outcomes. We further benchmarked multiple machine-learning strategies and established a 10-gene prognostic model that retained predictive performance across independent cohorts, with IMPDH1 emerging as the strongest risk-associated feature. Functional experiments confirmed the biological relevance of IMPDH1: its knockdown suppressed ccRCC cell proliferation, DNA synthesis, colony formation, and migration, whereas overexpression produced the opposite effects. Together, these findings indicate that acteoside-related molecular signatures capture clinically relevant heterogeneity in ccRCC and provide a framework for linking dietary-polyphenol-related molecular space with tumor biology. The identification and functional validation of IMPDH1 further highlight its potential importance in ccRCC progression.

IMPDH1↗

Measuring health status? A review of the sickness impact and functional limitations profiles.

Recent years have witnessed a growing interest in the measurement of health status. One of the most well-known health status instruments is the Sickness Impact Profile (SIP). This paper examines the nature, development and testing of the SIP (and its UK equivalent the FLP). The practical merits of these instruments are explained, and some cautionary remarks are offered about their limitations.

Evaluation Studies as Topic↗

Acceptor activity, isoacceptor profiles and function in protein synthesis of transfer RNAs from regenerating skeletal muscle.

Transfer RNAs have been prepared from control and regenerating rat skeletal muscle. The yield of tRNA is highest during the early stages of the regeneration process (5 and 8 days following the induction of regeneration) and decreases to near control values thereafter. The amino acid acceptor activity (extent of aminoacylation) of tRNA from regenerating muscle was also found to be higher for some amino acids than the activity of control tRNA, and the maximum increase in activity was observed between 5 and 8 days following the initiation of regeneration with a decrease to control levels through 15 and 30 days. The isoacceptor pattern, determined by RPC-5 chromatography, for methionyl-tRNAs from control muscle and 5-day regenerating muscle were essentially indistinguishable, while a minor peak of prolyl-tRNA was observed in the population from 5-, 8- and 15-day regenerates which was apparently absent from the control tRNA. Lysyl-tRNAs from control muscle contain two major isoacceptors while a third isoacceptor is observed in the tRNA preparations from 5-, 8- and 15-day regenerating muscle. The relative amount of this third isoacceptor is highest in the 8-day population and decreases in amount in tRNAs from 15- and 30-day regenerates. Control muscle also contains two major glutamyl-tRNA species while a third isoacceptor can be detected in regenerates. The relative amount of this species increases during the early course of the regeneration process but is present at near control levels by 30 days following Marcaine injection. Cell-free protein synthesis using muscle polyribosomes showed that tRNAs from regenerating muscle were more effective in stimulating [35S]methionine incorporation than tRNAs from control muscle.

Amino Acids↗