Differential Protein Expressions in Virus-Infected and Uninfected Trichomonas vaginalis

Protozoan viruses may influence the function and pathogenicity of the protozoa. Trichomonas vaginalis is a parasitic protozoan that could contain a double stranded RNA (dsRNA) virus, T. vaginalis virus (TVV). However, there are few reports on the properties of the virus. To further determine variations in protein expression of T. vaginalis, we detected 2 strains of T. vaginalis; the virus-infected (V⁺) and uninfected (V⁻) isolates to examine differentially expressed proteins upon TVV infection. Using a stable isotope N-terminal labeling strategy (iTRAQ) on soluble fractions to analyze proteomes, we identified 293 proteins, of which 50 were altered in V⁺ compared with V⁻ isolates. The results showed that the expression of 29 proteins was increased, and 21 proteins decreased in V⁺ isolates. These differentially expressed proteins can be classified into 4 categories: ribosomal proteins, metabolic enzymes, heat shock proteins, and putative uncharacterized proteins. Quantitative PCR was used to detect 4 metabolic processes proteins: glycogen phosphorylase, malate dehydrogenase, triosephosphate isomerase, and glucose-6-phosphate isomerase, which were differentially expressed in V⁺ and V⁻ isolates. Our findings suggest that mRNA levels of these genes were consistent with protein expression levels. This study was the first which analyzed protein expression variations upon TVV infection. These observations will provide a basis for future studies concerning the possible roles of these proteins in host-parasite interactions.

Poly(ADP-ribose) polymerase regulates glycolytic activity in kidney proximal tubule epithelial cells / 대한해부학회지

After renal injury, selective damage occurs in the proximal tubules as a result of inhibition of glycolysis. The molecular mechanism of damage is not known. Poly(ADP-ribose) polymerase (PARP) activation plays a critical role of proximal tubular cell death in several renal disorders. Here, we studied the role of PARP on glycolytic flux in pig kidney proximal tubule epithelial LLC-PK1 cells using XFp extracellular flux analysis. Poly(ADP-ribosyl)ation by PARP activation was increased approximately 2-fold by incubation of the cells in 10 mM glucose for 30 minutes, but treatment with the PARP inhibitor 3-aminobenzamide (3-AB) does-dependently prevented the glucose-induced PARP activation (approximately 14.4% decrease in 0.1 mM 3-AB-treated group and 36.7% decrease in 1 mM 3-AB-treated group). Treatment with 1 mM 3-AB significantly enhanced the glucose-mediated increase in the extracellular acidification rate (61.1±4.3 mpH/min vs. 126.8±6.2 mpH/min or approximately 2-fold) compared with treatment with vehicle, indicating that PARP inhibition increases only glycolytic activity during glycolytic flux including basal glycolysis, glycolytic activity, and glycolytic capacity in kidney proximal tubule epithelial cells. Glucose increased the activities of glycolytic enzymes including hexokinase, phosphoglucose isomerase, phosphofructokinase-1, glyceraldehyde-3-phosphate dehydrogenase, enolase, and pyruvate kinase in LLC-PK1 cells. Furthermore, PARP inhibition selectively augmented the activities of hexokinase (approximately 1.4-fold over vehicle group), phosphofructokinase-1 (approximately 1.6-fold over vehicle group), and glyceraldehyde-3-phosphate dehydrogenase (approximately 2.2-fold over vehicle group). In conclusion, these data suggest that PARP activation may regulate glycolytic activity via poly(ADP-ribosyl)ation of hexokinase, phosphofructokinase-1, and glyceraldehyde-3-phosphate dehydrogenase in kidney proximal tubule epithelial cells.

Potential Role of Bacterial Infection in Autoimmune Diseases: A New Aspect of Molecular Mimicry

Molecular mimicry is an attractive mechanism for triggering autoimmunity. In this review, we explore the potential role of evolutionary conserved bacterial proteins in the production of autoantibodies with focus on granulomatosis with polyangiitis (GPA) and rheumatoid arthritis (RA). Seven autoantigens characterized in GPA and RA were BLASTed against a bacterial protein database. Of the seven autoantigens, proteinase 3, type II collagen, binding immunoglobulin protein, glucose-6-phosphate isomerase, alpha-enolase, and heterogeneous nuclear ribonuclear protein have well-conserved bacterial orthologs. Importantly, those bacterial orthologs are also found in human-associated bacteria. The wide distribution of the highly conserved stress proteins or enzymes among the members of the normal flora and common infectious microorganisms raises a new question on how cross-reactive autoantibodies are not produced during the immune response to these bacteria in most healthy people. Understanding the mechanisms that deselect auto-reactive B cell clones during the germinal center reaction to homologous foreign antigens may provide a novel strategy to treat autoimmune diseases.

Value of four serum markers in the diagnosis of rheumatoid arthritis / 南方医科大学学报

<p><b>OBJECTIVE</b>To systematically evaluate the values of 4 serum markers in the diagnosis of rheumatoid arthritis (RA).</p><p><b>METHODS</b>Serum samples were obtained from 278 RA patients and 510 control subjects and the levels of rheumatoid factor (RF), anticyclic citrullinated peptide antibody (CCP), antikeratin antibody (AKA), and glucose-6-phosphate isomerase (GPI) were detected using immune turbidimetry, ELISA, indirect immunofluorescence, and ELISA, respectively. The values of these 4 serum markers and their combinations in RA diagnosis were systemically assessed.</p><p><b>RESULTS</b>In RA diagnosis using one serum marker, two markers, and three or four markers, RF, RF+CCP, RF+CCP+GPI, respectively, had the highest sensitivity; CCP, CCP+AKA, and RF+CCP+AKA+GPI, respectively, had the highest specificity; CCP, CCP+GPI, and RF+CCP+AKA+GPI, respectively, had the highest positive predictive value; GPI, RF+CCP, and RF+CCP+GPI, respectively, had the highest negative predictive value; CCP, CCP+GPI, and RF+CCP+AKA+GPI, respectively, had the highest positive likely ratio; GPI, RF+CCP, and RF+CCP+GPI, respectively, had the lowest negative likely ratio.</p><p><b>CONCLUSION</b>CCP, RF+CCP, and RF+CCP+GPI are the most ideal for RA diagnosis using one, two, and three or more markers, respectively. CCP is the essential marker for RA diagnosis, and a combined detection of the serum makers can significantly improve the diagnostic accuracy.</p>

Diagnostic value of glucose-6-phosphate isomerase in rheumatoid arthritis patients: systematic review / 生物医学工程学杂志

In order to evaluate the diagnostic accuracy of glucose-6-phosphate isomerase in patients with rheumatoid arthritis, retrieval was performed using the data bases of Medline, Embase, Cochrane library, Cmcc and Cbmdisc (1990 to 2007). We included the articles which reported the studies of GPI measured by enzyme-linked immunosorbent assay in the diagnosis of RA patients. Then we reviewed 15 article and used RevMan Software for analysis; the heterogeneity among the articles was determined to be high (chi2 = 191.65, P < 0.00001). When we analyzed the 5 articles wherein serum was used as the standard, we noticed homogeneity (chi2 = 6.97, P = 0.14). The summary sensitivity was 25%; the summary specificity was 80%; the area under the curve was 0.6279. Our study demonstrated that GPI exhibited high specificity and low sensitivity in diagnosing RA cases. We suggest that GPI be used in conjunction with some assay or other that is characterized by high sensitivity.

Modulatory effect of Gynandropsis gynandra L. on glucose metabolizing enzymes in aflatoxin B1-induced hepatocellular carcinoma in rats.

The modulation of glucose-metabolizing enzymes activities play a vital role in the depletion of energy metabolism and leads to inhibition of cancer growth. In the present study, the effect of Gynandropsis gynandra L. extract on aflatoxin B1 (AFB1)-induced hepatocellular carcinoma (HCC) was studied on glucose-metabolizing enzymes in rats. A significant increase (p < 0.001) in the activities of the key glycolytic enzymes viz., hexokinase and phosphoglucoisomerase, with a significant decrease (p < 0.001) in the gluconeogenic enzymes glucose-6-phosphatase and fructose-1,6-bisphosphatase were observed in HCC-bearing rats, when compared with the control. Administration of G. gynandra extract caused a significant decrease in the activities of glycolytic enzymes and an increase in the gluconeogenic enzymes activities to near normal values. Thus, findings suggest the G. gynandra extract has a definite modulating role on the key enzymes of glucose metabolism in HCC. The modulatory effect may be due to the phytoactive constituents present in the extract of G. gynandra.

Studies on glucose-metabolizing enzymes in cytosolic and bacteroidal fractions of mungbean (Vigna radiata L.) and lentil (Lens culinaris L.) nodules.

Nitrogen is exported in the form of ureides or amides from the nodules in pulse crops. In order to understand the carbon metabolism in ureide and amide exporting nodules, activities of enzymes involved in glucose metabolism were compared in cytosolic and bacteroidal fractions of mungbean (ureide exporter) and lentil (amide exporter) nodules during development. Activities of hexokinase, fructokinase, phosphoglucomutase, fructose-1,6-bisphosphatase, phosphohexose isomerase and UDP-glucose pyrophosphorylase were detected in cytosolic fraction of nodules of both the crops during development. Out of these enzymes, specific activity of phosphohexose isomerase was the highest in nodules of both the crops, in comparison with other enzymes. In comparison with mungbean, activities of various enzymes were less in cytosolic fraction of lentil. Activities of hexokinase, fructokinase, phosphoglucomutase were present only in cytosolic fraction of mungbean (Vigna radiata L.), however, low activity of these enzymes was also observed in lentil (Lens culinaris L.) bacteroids. Activities of phosphohexose isomerase and fructose-1,6-bisphosphatase were higher in bacteroids of lentil, as compared to mungbean during early nodule development, but this pattern was reversed with progress of crop development. Higher activities of phosphoglucomutase and fructose-1,6-phosphatase in mungbean cytosolic fraction could lead to increased flow of carbon towards pentose phosphate pathway.

Clinical Significance of Autoantibodies to Glucose-6-phosphate Isomerase in Serum of Patients with Rheumatoid Arthritis / 대한류마티스학회지

OBJECTIVE: Anti-glucose-6-phosphate isomerase (GPI) antibody (Ab) is known to be arthritogenic in K/BxN mice. Anti-GPI Ab is present in some patients with rheumatoid arthritis (RA), but their clinical manifestations are not clearly elucidated. The purpose of this study was to evaluate whether GPI serves as a specific autoantigen in patients with RA and to investigate the relationship of anti-GPI Ab with clinical parameters of RA. METHODS: Sera were collected from 54 patients with RA, 15 patients with osteoarthritis (OA) and 28 healthy controls. The samples were tested by enzyme-linked immunosorbent assay (ELISA) using human recombinant GPI as antigen. Patients with RA were classified according to rheumatoid factor (RF) positivity, the presence of RA shared epitope (SE), the presence of extraarticular manifestations, and evidence of bony erosive changes. RESULTS: Serum levels of anti-GPI Ab were higher in patients with RA than controls (1599.46+/-1022.48 versus 344.82+/-223.16 AU, p<0.001), and the levels of patients with OA were also higher than controls (1161.47+/-917.44 versus 344.82+/-223.16 AU, p<0.01). In RA, there were no significant difference in anti-GPI Ab levels according to RF positivity, the presence of RA SE, the presence of extraarticular manifestations, and evidence of bony erosive changes. CONCLUSION: Our results suggest that anti-GPI Ab may not be RA specific Ab and not related to the severity of RA.

Inhibitory effect of YC-1 on induction of VEGF and GPI genes in hypoxic human pancreatic cancer cells / 中华肿瘤杂志

<p><b>OBJECTIVE</b>To investigate the function and mechanism of 3-(5'-hydroxymethyl-2'-furyl)-1-benzylindazole (YC-1) on activity of VEGF and GPI genes in human pancreatic cancer PC-3 cells incubated under hypoxic conditions.</p><p><b>METHODS</b>Human pancreatic cancer PC-3 cells were incubated under hypoxic culture conditions. Immunocytochemical staining was used to detect HIF-1alpha protein expression in hypoxic and normoxic PC-3 cells. Semi-quantitative RT-PCR was used to detect the effect of YC-1 on the expression of VEGF and GPI mRNA and HIF-1alpha protein in PC-3 cells. Effect of YC-1 on the expression of HIF-1alpha protein was examined by Western blotting. MTF assay was used to detect proliferation of hypoxicPC-3 cells.</p><p><b>RESULTS</b>HIF-1alpha expression was mainly located in nuclei in hypoxic PC-3 cells. The mRNA synthesis of VEGF and GPI and the protein expression of HIF-1alpha were significantly decreased in the group treated with the highest concentration of YC-1 (100 micromol/L). Compared to placebo, YC-1 inhibited the proliferation of hypoxic PC-3 cells greatly when it was increased to 100 micromol/L.</p><p><b>CONCLUSION</b>YC-1 inhibited the transcription of VEGF and GPI in hypoxic human pancreatic cancer PC-3 cells. It was induced by down-regulation of HIF-1alpha protein. YC-1 inhibites the proliferation of PC-3 cells exposed to hypoxic conditions.</p>

Effect of synthesized niclosamide organophosphortus derivatives on some metabolic aspects of Biomphalaria alexandrina snails and its compatibility to Schistosoma mansoni

The Molluscicidal potency of four synthesized Mannich bases and ten organophosphorus derivatives of bayluscide [niclosamide] were determined. Using Biomphalaria alexandrina snail, the intermediate host to Schistosoma mansoni in Egypt, of these derivatives,a single Mannich bases derivative [compound No, 13] showed higher molluscicidal effect than niclosamide, LC[50] 0.4 ppm after 24 hours at 25°C compared with 0.5 ppm for niclosamide. Three other derivatives [No. 15, 12 and 8] showed slightly less effect, their LC[50] 1.9, 3.4 and 4.1 ppm, respectively, Meanwhile, the four compounds showed considerable reducting effect on the cercarial production of schistosome-infected snails previously exposed to LC[5] of each compound before miracidial infection. Thus, the mean periodic number of cercariae/snail [two hours weekly] was found to be 55.8 +/- 41.8, 95.9 +/- 78.9, 162.6 +/- 145 and 209.35 +/- 168.4 cercariae/snail, respectively versus 242 +/- 230.4 and 502 +/- 290.4 in the case of niclosamide-treated and non-treated snails. The effect of the four compounds was tested on the glycolytic enzymes of snails, namely, hexolinase [HK], pyruvate kinase [PK] and glucose phosphate isomerase [GPI]. Much more reduction was recognized in [HK] by compounds No. 8 and 13 in comparison, with niclosamide and nontreated snails, being 2.6 +/- 0.82 and 3.7 +/- 1.6 n moles/min/g tissue versus 3.9 +/- 0.58 and 9.8 +/- 2.7 n moles/min/g tissue in niclosamide-treated and non-treated groups, respectively. PK showed also higher reduction with four compounds namely 15, 13, 12 and 8 compared with niclosamide-treated and non-treated snails, being 0.3 +/- 0.1, 0-.39 +/- 0.29, 0.46 +/- 0.08 and 0.98 +/- 0.138 in comparison with 1.51 +/- 0.52 and 1.8 +/- 0.62, respectively. No considerable change was found in the level of GPI in snails treated with 15, 13, 12 and 8 compounds relative to niclosamide-tested snails. The present results show that reduction in the periodic cercarial production is correlated with the lower level of HK enzyme in treated snails

Evaluation of isoenzyme patterns for identification of pathogenic poultry Mycoplasmas

Electrophoretic analysis of isoenzymes in 8 enzymatic systems were used for differentiation of 4 isolates of chicken Mycoplasmas including two strains of M gallisepticum, one strain of M. gallinarum and one unknown isolate in comparison with a vaccinal strain of M agalactiae that basically is a pathogen in small ruminants. The enzymatic systems were lactate dehydrogenase [LDH], glucose dehydrogenase [G1DH], glucose 6 phosphate dehydrogenase [G6PD], galactose dehydrogenase [GalDH], 6 phosphogluconate dehydrogenase [6PGDH], malic enzyme [ME], glucose phosphate isomerase [GPI] and alkaline phosphatase [AP]. The number of isoenzyme patterns obtained for LDH, G1DH, G6PD, GalDH, 6PGDH, ME, GPI and AP enzymatic systems were 2, 3, 2, 4, 2, 3, 3 and 0, respectively. Except AP enzyme system which is not active in Mycoplasma species, it is concluded that isoenzyme pattern of 7 other studied enzymatic systems, could differentiate between chicken Mycoplasmas and the small ruminant's strain. Based on the isoenzyme patterns of GalDH system, 2 strains of M gallisepticum were differentiated from M. gallinarum and the unknown isolate. Isoenzyme patterns of ME system was able to differentiate M gallinarum from the other chicken isolates. The isoenzyme patterns of GPI system were different for the two strains of M gallisepticum. The isoenzyme patterns of GalDH, GPI and ME systems, showed that the unknown strain of chicken Mycoplasma is a strain of M gallisepticum and it is closely related to one of the known M. gallisepticum isolates

Clinical Significance of Autoantibodies to Glucose-6-Phosphate Isomerase in Synovial Fluid of Patients with Rheumatoid Arthritis / 대한류마티스학회지

OBJECTIVE: Autoantibody against glucose-6-phosphate isomerase (GPI) has been shown to be present in both the serum and synovial fluid (SF) of patients with rheumatoid arthritis (RA). The purpose of this study was to evaluate whether GPI serves as a specific autoantigen in the SF of patients with RA and to investigate the relationship of anti-GPI antibody with clinical parameters of RA. METHODS: SF was collected from 34 patients with RA and 34 patients with osteoarthritis (OA). The samples were tested by enzyme-linked immunosorbent assay (ELISA) using human recombinant GPI as antigen. Patients with RA were classified according to rheumatoid factor (RF) positivity, the presence of RA shared epitope, the presence of extraarticular manifestations, and evidence of bony erosive changes. RESUTLS: SF levels of anti-GPI antibody were higher in patients with RA than in patients with OA (631.12+/-534.02 AU versus 112.38+/-90.45 AU, p<0.001). In RA, there was no significant difference in SF anti-GPI antibody levels according to RF positivity, the presence of extraarticular manifestations, and evidence of bony erosive changes. CONCLUSION: Autoantibodies to GPI in SF have more related with patients with RA compared with those with OA. In patients with RA, autoantibodies to GPI in SF are not associated with the poor prognostic factors and disease activity of RA.

Metabolic flux analysis of L-valine fermentation in Corynebacterium glutamicum / 生物工程学报

In industrial fermentation of amino acids the cells are often forced to synthesize the biochemicals excessive of their physiological needs. The knowledge of metabolic networks and their regulation relevant usually come from biochemical research, especially from enzymology, not from engineering study. To enrich the knowledge of metabolic sub-network of L-valine syntheses for higher production of L-valine, Corynebacterium glutamicum AS1.495 and its genetic derivatives AA361, AAT231, AATV341 were used for metabolic flux analysis. AS1.495 is a leucine auxotrophic (Leu-), and the three derivatives carry additional mutations. AA361 contains D-aspartic acid-beta-hydroxamate supersensitive marker (Leu-, L-AAHss), AAT231 (Leu-, L-AAHss, 2-TAr) is D-aspartic acid-beta-hydroxamate supersensitive and 2-thiazole alanine resistant, and AAT341 (Leu-, L-AAHss, 2-TAr, Vd-) is a D-aspartic acid-beta-hydroxamate supersensitive, 2-thiazole alanine resistant and valine-decompose-ability imperfect (Vd-). The concentrations of extra-cellular metabolites were determined under sub-steady-state of the batch culture. The metabolic flux distribution maps of the four strains were obtained, compared and analyzed. Our analysis showed that the flux ratio of EMP and HMP from the glucose-6-phosphate had increased from 0.205 in the parental strain AS1.495 to 0.321 in the multiple-mutation strain AATV341; the flux ratio of L-valine synthesis branch and the rest branches from the pyruvate node increased from 0.188 in AS1.495 to 3.29 in AATV341; the flux of lactic acid synthesis branch decreased from 11.1 in AS1.495 to 1.16 in AATV341; the flux of L-valine synthesis branch increased from 5.37 in AS1.495 to 37.3 in AATV341; and the productivity of L-valine correspondently increased from 4 g/L in AS1.495 to 24.5 g/L in AATV341. These results indicate that the introduction of analog supersensitive marker L-AAH55 and/or analog resistant marker 2-TAr skew the metabolic flux towards the formation of L-valine. This study revealed the usefulness of the metabolic flux analysis as a tool for verification of existing production strains. The analysis may play an important role in helping us b to rationally re-design metabolism for further improvement of fermentation process.

Detection of antibodies against glucose 6-phosphate isomerase in synovial fluid of rheumatoid arthritis using surface plasmon resonance (BIAcore)

We have used a surface plasmon resonance biosensor (SPR, BIACORE 2000) to detect antibodies against glucose 6-phosphate isomerase (GPI) in synovial fluids of rheumatoid arthritis (RA) and osteoarthritis (OA). Recombinant human GPI proteins fused with or without NusA were expressed in E. coli, purified to homogeneity and immobilized in flow cells of CM5 sensor chips. The flow cells immobilized with NusA protein or bovine serum albumin were used to monitor non-specific binding. Synovial fluid samples from RA patients showed a significantly higher level of binding to recombinant GPI proteins than samples from OA patients. Proteins which bound to the recombinant GPI proteins were confirmed to be immunoglobulin through the administration of anti-human immunoglobulin. NusA fusion protein was excellent for this assay because of a low background binding activity in the SPR analysis and its advantage of increased solubility in recombinant protein production. These results suggested a useful utilization of recombinant NusA-GPI fusion protein for the detection of autoantibodies against GPI in RA patients.

Protection against methanol intoxication in rat liver enzymes by vitamins C and E

Antioxidant [AO] effects of vitamins C and E on the alteration of some enzymes of glucose metabolism induced by repeated doses of methanol were studied in rat livers. The selected enzymes include hexokinase [HK], glucose phosphate isomerase [GPI] and pyruvate kinase [PK] as glycolytic enzymes as well as fructose 1,6-diphosphatase [F-1,6 DP] as gluconeogenic enzyme. The results showed that methanol caused a pronounced decay in the activities of the all measured enzymes. AO vitamins administration showed a high protective effects indicated by significant increase in the activities of these enzymes. This may be attributed to the inhibition of free radical production induced by toxic effect of methanol with subsequent minimum degree of tissue damage

red fox, vulpes v. Aegyptiaca, a new host of leishmania major in Sinai peninsula

A leishmanial isolate was obtained from the ear of one red fox or Nile fox [Vulpes v. aegyptiaca] out of eight from North Sinai Governorate. The isolate was typed by the enzymatic variant profiles of the four enzymes, GPI, G6PD, 6PGD and PGM against the three old world reference strains, L. major, L. Tropica and L. Donovani and proved to be Leishmania major. This is the second time that L. major appeared to occur in canine hosts. The list of the mammalian hosts of L. Major was reviewed and discussed

In vivo, attenuation of Schistosome cercarial development and disturbance of egg laying capacity in Biomphalaria alexandria using sublethal concentrations of plant molluscicides

The dry powder of Sinapis arvensis, Thymelaea hirsuta, Callistemon lanceolatus and Peganum harmala showed molluscicidal activity against Biomphalaria alexandrina, specific intermediate hosts to Schistosoma mansoni. Effect of LC[25] of dry powdered plant molluscicdes on hexokinase [HK], glucose phosphate isomerase [GPI], AMP deaminase, adenosine deaminase and phenol oxidase [PO] of B. alexandrina was traced. C. lanceolatus showed the highest molluscicidal activity as it has the lowest LC[50] compared to S. arvensis, T. hirsuta, and P. harmala, LC[25] of the latter three plants resulted in more significant inhibition of HK, GPI, AMP deaminase and PO than C. lanceolatus. Treatment of snails with LC[10] of these plants markedly affected compatibility of B. alexandrina to S. mansoni infection. Significant decrease in cercarial production was recorded in snails treated with sublethal concentrations of S. arvensis, T. hirsuta, and P. harmala. Remarkable impairment of the egg laying capacity of molluscicide treated snails was also recorded. Correlation between activity levels of HK, GPI and AMP deaminase and compatibility to parasitic infection and role of PO in the egglaying capacity of these snail species were discussed

Karyological, biochemical, and physiological aspects of Callophysus macropterus (Siluriformes, Pimelodidae) from the Solimöes and Negro Rivers (Central Amazon)

Karyological characteristics, i.e., diploid number, chromosome morphology and nucleolus organizer regions (NORs), biochemical characteristics, i.e., electrophoretic analysis of blood hemoglobin and the tissue enzymes lactate dehydrogenase (LDH), malate dehydrogenase (MDH), alcohol dehydrogenase (ADH), and phosphoglucose isomerase (PGI), and physiological characteristics, i.e., relative concentration of hemoglobin and intraerythrocytic concentrations of organic phosphates were analyzed for the species Callophysus macropterus collected from Marchantaria Island (white water system - Solimöes River) and Anavilhanas Archipelago (black water system - Negro River). Karyological and biochemical data did not reveal significant differences between specimens collected at the two sites. However, the relative distribution of hemoglobin bands I and III (I = 16.33 ñ 1.05 and III = 37.20 ñ 1.32 for Marchantaria specimens and I = 6.33 ñ 1.32 and III = 48.05 ñ 1.55 for Anavilhanas specimens) and levels of intraerythrocytic GTP (1.32 ñ 0.16 and 2.76 ñ 0.18 for Marchantaria and Anavilhanas specimens, respectively), but not ATP or total phosphate, were significantly different, indicating a physiological adaptation to the environmental conditions of these habitats. It is suggested that C. macropterus specimens from the two collecting sites belong to a single population, and that they adjusted some physiological characteristics to adapt to local environmental conditions.

Effect of protein malnutrition on the glycolytic and glutaminolytic enzyme activity of rat thymus and mesenteric lymph nodes

The activity of important glycolytic enzymes (hexokinase, phosphofructokinase, aldolase, phosphohexoseisomerase, pyruvate kinase and lactate dehydrogenase) and glutaminolytic enzymes (phosphate-dependent glutaminase) was determined in the thymus and mesenteric lymph nodes of wistar rats submited to protein malnutrition (6 percent protein in the diet rather than 20 percent) from conception to 12 weeks after birth. The wet weight (g) of the thymus and mesenteric lymph nodes decreased due to protein malnutrition by 87 percent (from 0.30 + 0.05 to 0.04 + 0.01) and 75 percent (0.40 + 0.04 to 0.10 + 0.02), respectively. The protein content was reduced only in the thymus from 102.3 + 4.4 (control rats) to 72.6 + 6.6 (malnourished rats). The glycolytic enzymes were not affected by protein malnutrition, but the glutaminase activity of the thymus and lymph nodes was reduced by halfing in protein-malnourished rats as compared to controls. This fact may lead to a decrease in the cellularity of the organ and thus in its size, weight and protein content.

Enzimas en el jugo gastrico: una ayuda para el diagnostico del cancer gastrico / Enzymes in the gastric juice: an aid in the diagnosis of gastric cancer

In the present study we measured the activities of the following enzymes: LDH (lactic dehydrogenase), beta-glucuronidase, acid maltase, phosphohexoseisomerase (PHI) and acid proteases in the gastric juice of patients with gastric cancer (n = 50) (Case Group), in endoscopically normal subjects (n = 50) and in subjects with different non tumor-like digestive pathologies (n = 55) (Control Groups). In the patients with gastric carcinoma we found a significant increase in LDH, beta-glucuronidase, PHI and acid maltase activities and a decreased activity of acid proteases. The results agree with previous findings from other workers. The variations of enzyme activities in gastric juice can help to differentiate between malignant and benign processes of the gastric mucosa.