Influence of the Ripening Time on the Viscoelastic Behaviour of Tetilla Cheese

Controlled shear stress tests were used to monitor the changes of viscoelastic properties in industrial samples of Tetilla cheese with the ripening time. The linear viscoelastic range was determined from both stress sweep and creep-and-recovery tests conducted at 20ºC. One-week-old samples were found to be more rigid and elastic, and to exhibit broader linear ranges, than older samples. Mechanical spectra recorded at the same temperature confirmed this trend since viscoelastic moduli G’ and G" decreased markedly during the first week of ripening, indicating a loss of structure during this period. Besides, physico-chemical information (pH, water content, protein content, nitrogen fractions, and s1 and β casein fractions) was obtained by analytical methods. Quite good correlation between rheological and chemical results was found. For each ripening time, an additional study of mechanical spectra as a function of temperature was performed. A marked increase of the power law exponents as temperature is raised is observed after the second week. Crosslink breakdown and the resulting structural weakening of the micellar network through casein hydrolysis during ripening can explain this result. The whole study provided similar results to those found for other type of cheeses and, also, allowed the classification of samples into two groups of markedly different behaviour, namely, one-week-old samples and older samples. In conclusion more than one week of ripening is needed to reach the adequate texture standardisation of Tetilla cheese.

Activity of phosphoglycerate mutase and its isoenzymes in serum after acute myocardial infarction

Aims/background-In humans there are three phosphoglycerate mutase (PGM, EC 5.4.12.1) isoenzymes (MM, MB and BB) which have similar distribution and developmental pathways to creatine kinase (CK, EC 2.7.3.2) isoenzymes. Total serum PGM activity increases in acute myocardial infarction with the same time course as creatine kinase activity. The present study was undertaken to determine changes in the activity of PGM and its isoenzymes after acute myocardial infarction.Methods-PGM activity was measured spectrophotometrically, by coupling the formation of 2-phosphoglycerate from 3-phosphoglycerate with enolase, pyruvate kinase and lactate dehydrogenase catalysed reactions. Inter- and intra-assay reproducibility was assessed. PGM isoenzyme activities were measured using cellulose acetate electrophoresis.Results-Total PGM activity in serum was increased in patients with a confirmed diagnosis of acute myocardial infarction. PGM activity peaked 12 to 24 hours after the onset of symptoms and returned to normal values within 48 hours. Electrophoretic analysis of serum from healthy subjects showed a band corresponding to BB-PGM and two other artefactual bands that did not correspond to adenylate kinase. After myocardial infarction, BB-PGM activity increased and MB-PGM and MM-PGM could be detected. On immunoblot analysis, normal serum contained an inactive form of MM-PGM with a smaller molecular weight than that of PGM tissue isoenzymes.Conclusions-Total serum PGM activity increased in patients with acute myocardial infarction, following the same temporal course as creatine kinase activity. The increase in MM-PGM and MB-PGM activities in these patients was not as high as expected. It is suggested that PGM isoenzymes, after release into the blood, undergo postsynthetic, probably proteolytic, transformation.

Highly precise experimental device for determining the heat capacity of liquids under pressure

An experimental device for making isobaric heat capacity measurements of liquids under pressure is presented. The device is an adaptation of the Setaram micro-DSC II atmospheric-pressure microcalorimeter, including modifications of vessels and a pressure line allowing the pressure in the measurement system to be set, controlled, and stabilized. The high sensitivity of the apparatus combined with a suitable calibration procedure allows very accurate heat capacity measurements under pressure to be made. The relative uncertainty in the isobaric molar heat capacity measurements provided by the new device is estimated to be 0.08% at atmospheric pressure and 0.2% at higher levels. The device was validated from isobaric molar heat capacity measurements for hexane, nonane, decane, undecane, dodecane, and tridecane, all of which were highly consistent with reported data. It also possesses a high sensitivity as reflected in its response to changes in excess isobaric molar heat capacity with pressure, which were examined in this work for the first time by making heat capacity measurements throughout the composition range of the 1-hexanol+n-hexane system. Finally, preliminary measurements at several pressures near the critical conditions for the nitromethane+2-butanol binary system were made that testify to the usefulness of the proposed device for studying critical phenomena in liquids under pressure.

Viscosity anomaly near the critical point in nitrobenzene + alkane binary systems

The viscosity near the critical point in nitrobenzene+hexane and nitrobenzene+heptane binary systems was studied by examining the viscosity values for critical mixtures at a variable temperature as obtained with a falling-ball viscometer. The regular part of the viscosity of the critical mixtures was calculated by interpolating measurements made at noncritical concentrations. Because viscosity anomaly studies must be conducted at zero shear, a method allowing the estimation of the effective shear for this type of viscometer was developed with a view to introducing the corrections required. This methodology was used to determine the critical exponent for the viscosity anomaly in nitrobenzene+hexane and nitrobenzene+heptane systems, which were found to be 0.0422+/-0.0004 and 0.0432+/-0.0013 , respectively, very consistent with the accepted value: 0.043.

Assessing relationships between health-related quality of life and adherence to antiretroviral therapy

OBJECTIVE

To investigate associations between health-related quality of life (HRQoL), as assessed using the multidimensional quality of life-HIV (MQOL-HIV) questionnaire, and adherence to antiretroviral treatment in HIV-infected subjects.

DESIGN

Multicentre cross-sectional study in three institutional tertiary hospitals in northwest Spain.

PATIENTS AND METHODS

The MQOL-HIV was completed by 235 HIV-infected adults undergoing antiretroviral treatment. Adherence to antiretroviral therapy was assessed by using patient's self-report. Information about sociodemographic characteristics and clinical variables was also collected.

RESULTS

Good adherence (> or = 95% of prescribed pills correctly taken) was reported by 131 patients (55.7%). Univariate analyses indicated that the sociodemographic and clinical variables associated with adherence were age, educational level, income, employment, home stability, transmission route, history of previous antiretroviral therapy, and number of prescribed pills/day. Subscales of MQOL-HIV associated with adherence were mental health, cognitive functioning, financial status, medical care, partner intimacy, and (in men only) sexual functioning. Stepwise logistic regression showed that good adherence was more frequent in patients aged > 40 years (odds ratio, OR: 2.50; 95% confidence interval, CI: 1.15-5.61) and in patients with high cognitive functioning (OR: 2.26; 95% CI: 1.19-4.30). Conversely, poor adherence was more frequent in patients without stable home (OR: 2.96; 95% CI: 1.39-6.32), in patients required to take 14 or more pills/day (OR: 2.17; 95% CI: 1.18-4.28), in patients with low financial status (OR: 3.42; 95% CI: 1.57-7.45), and in patients reporting low medical care (OR: 2.07; 95% CI: 1.07-3.98).

CONCLUSIONS

HRQoL dimensions, notably cognitive functioning, financial status and medical care, are closely associated with antiretroviral therapy adherence.

Association of HCV and HBV markers in Spanish HIV-seropositive patients in relation to risk practices

BACKGROUND/AIMS

HBV, HCV, and HIV have some transmission routes in common. Viral liver disease is a leading cause of mortality in HIV-infected patients. The study was aimed at evaluating the prevalence of HBV and HCV markers in subjects with different risk practices for HIV infection.

METHODOLOGY

A total of 699 subjects were studied Of these subjects, 517 were intravenous drug users (373 HIV-positive and 144 HIV-negative), 127 had heterosexual risk practice (66 HIV-positive and 61 HIV-negative), 31 had homosexual risk practice (all HIV-positive), 15 had post-transfusional HIV infection, and nine had HIV infection of unknown source. Patients with anti-HBc antibody were considered HBV-positive, and cases with anti-HCV antibodies were considered HCV-positive.

RESULTS

Among patients with HIV infection, most intravenous drug users (79%) had markers of both HBV and HCV, compared with 20%, 11%, and 10% of cases infected by transfusional, heterosexual, and homosexual route, respectively (p < 0.001). Absence of both HBV and HCV markers was observed in most HIV-positive heterosexuals (62%) compared with 40% of post-transfusional cases, 32% of homosexuals and 4% of intravenous drug users (p: NS, p = 0.009, and p < 0.001, respectively). Isolated HBV-positivity was the most frequent pattern in HIV-infected homosexuals (58%), compared with 27% of post-transfusional, 21% of heterosexuals and 11% of intravenous drug users (p: NS, p < 0.001 and p < 0.001, respectively). HIV-negative intravenous drug users had a lower prevalence of HBV/HCV association than HIV-positive cases (p < 0.001). Isolated HCV-positivity was more frequent in HIV-negative than in HIV-positive intravenous drug users (27% vs. 6%, p < 0.001). In heterosexuals, isolated HBV-positivity was more prevalent in HIV-positive than in HIV-negative cases (21% vs. 7%, p = 0.04).

CONCLUSIONS

HBV and HCV seroprevalence in HIV infected patients vary depending on the risk practice. This suggests a variable transmissibility depending on the route considered. Within the same risk practice, differences in HCV and HBV seroprevalence between HIV-positive and HIV-negative cases suggest that some factors associated with HIV infection may influence the rate of infection by HCV and HBV.

Heat capacity and thermal expansion anomalies in the nitromethane-1-butanol mixture near its upper critical point

The heat capacity per unit volume C(p) and density rho of the nitromethane-1-butanol critical mixture near its upper consolute point are determined in this work. C(p) data are obtained at atmospheric pressure as a function of temperature in the one-phase and two-phase regions, using a differential scanning calorimeter. The suitability of DSC for recording C(p) as a function of T in the critical region is confirmed by measurements of the nitromethane-cyclohexane mixture, the results being quite consistent with reported data. By fitting the C(p) data in the one-phase region, the critical exponent alpha is found to be 0.110+/-0.014-and hence consistent with the universal accepted value-and the critical amplitude A(+)=0.0606+/-0.0006 J K(-1) cm(-3). Rho data were only obtained in the one-phase region, using a vibrating tube densimeter. The amplitude of the density anomaly was found to be C(+)(1)=-0.017+/-0.003 g cm(-3), which is moderately low in spite of the large difference between the densities of the pure liquids. The thermodynamic consistency of the A+ and C+1 values was examined in relation to the previously reported value for the slope of the critical line dT(c)/dp. The results of this analysis were consistent with previous work on this matter.

Decreased sensitivity of tristetraprolin-deficient cells to p38 inhibitors suggests the involvement of tristetraprolin in the p38 signaling pathway

Treatment of macrophages with pyridinyl imidazole inhibitors of p38 protein kinases can inhibit lipopolysaccharide-stimulated tumor necrosis factor alpha secretion. However, bone marrow-derived macrophages from tristetraprolin (TTP)-deficient mice were less sensitive than normal macrophages to this effect of p38 inhibitors, despite evidence for normal p38 activation in response to lipopolysaccharide. TTP is known to cause decreased stability of tumor necrosis factor alpha and granulocyte-macrophage colony-stimulating factor mRNAs after binding to an AU-rich element in their 3'-untranslated regions. A recombinant TTP fusion protein could be phosphorylated by a recombinant p38 kinase in cell-free assays and was phosphorylated to the same extent by immunoprecipitated p38 derived from normal and TTP-deficient cells stimulated with lipopolysaccharide; in both cases, the enzyme activity was inhibited by the p38 inhibitors. TTP phosphorylation also was increased in intact macrophages after lipopolysaccharide stimulation, an effect that was blocked by the p38 inhibitors. Finally, TTP in mammalian cell extracts bound less well to an AU-rich element RNA probe than did the same amount of TTP following dephosphorylation. These results suggest that TTP may be a component of the signaling cascade, initiated by inflammatory stimuli and mediated in part by activation of p38, that ultimately leads to enhanced secretion of tumor necrosis factor alpha.

Roles of tumor necrosis factor-alpha receptor subtypes in the pathogenesis of the tristetraprolin-deficiency syndrome

Tristetraprolin (TTP) is a member of the CCCH tandem zinc-finger class of proteins. It can bind to and destabilize mRNAs encoding tumor necrosis factor-alpha (TNF-alpha) and granulocyte-macrophage colony-stimulating factor (GM-CSF). Conversely, mice deficient in TTP develop a complex syndrome characterized by cachexia, myeloid hyperplasia, and joint and skin inflammation. Studies using anti-TNF-alpha neutralizing antibodies demonstrated that this syndrome, at least in part, is a consequence of the excess production of TNF-alpha in the absence of TTP. To evaluate the role played by each TNF-alpha receptor in the pathogenesis of this syndrome, mice were generated that were deficient in TTP and either or both of the known TNF-alpha receptors (TNFRs), type 1 (TNFR1) and type 2 (TNFR2). Mice deficient in TTP and TNFR1, or in TTP and both receptors, were protected from developing the TNF-alpha-induced cachexia and inflammation. In contrast, mice deficient in TNFR2 were more severely affected than mice deficient in TTP alone, suggesting that TNFR2 might play a protective role in the development of the syndrome. In cultured cells derived from these mice, apparent cooperation between the TNFRs was required to achieve normal TNF-alpha-induced expression of TTP, TNF-alpha, and GM-CSF mRNAs. Finally, the results showed that TNFR1 plays an important role in mediating TNF-alpha-induced changes in TNF-alpha and GM-CSF mRNA stability.

[A prospective randomized trial of the impact of misoprostol (PgE1) on pregnancy rate after intrauterine insemination (IUI) therapy: a preliminary report]

Although the use of prostaglandin plays an important role in the reproductive human physiology, it is still controversial in the reproductive field. Ovarian stimulation as well as intrauterine insemination increased the reproductive goals in certain group of patients. The objective of the present study was to evaluate the prostaglandin effect (misoprostol) in patients under ovarian stimulation and intrauterine insemination and their final outcome in the clinical pregnancy rate. There were a total of 59 ovarian stimulated cycles, the study group (n = 29) received 200 micrograms of prostaglandin E1 (misoprostol) intravaginal after IUI, compared with the control group (n = 30). Demographic characteristics were similar in both groups. There were no differences in age, FSH. LH and E2, hCG day and number of ampoules between groups. However, a significant pregnancy rate was observed between groups (31% study group vs. 20% control group). We concluded that prostaglandin application in stimulated cycles under intrauterine insemination remain a beneficial effect showing in the pregnancy outcome.

Interactions of CCCH zinc finger proteins with mRNA. Binding of tristetraprolin-related zinc finger proteins to Au-rich elements and destabilization of mRNA

Macrophages derived from tristetraprolin (TTP)-deficient mice exhibited increased tumor necrosis factor alpha (TNFalpha) release as a consequence of increased stability of TNFalpha mRNA. TTP was then shown to destabilize TNFalpha mRNA after binding directly to the AU-rich region (ARE) of the 3'-untranslated region of the TNFalpha mRNA. In mammals and in Xenopus, TTP is the prototype of a small family of three known zinc finger proteins containing two CCCH zinc fingers spaced 18 amino acids apart; a fourth more distantly related family member has been identified in Xenopus and fish. We show here that representatives of all four family members were able to bind to the TNFalpha ARE in a cell-free system and, in most cases, promote the breakdown of TNFalpha mRNA in intact cells. Because the primary sequences of these CCCH proteins are most closely related in their tandem zinc finger domains, we tested whether various fragments of TTP that contained both zinc fingers resembled the intact protein in these assays. We found that amino- and carboxyl-terminal truncated forms of TTP, as well as a 77 amino acid fragment that contained both zinc fingers, could bind to the TNFalpha ARE in cell-free cross-linking and gel shift assays. In addition, these truncated forms of TTP could also stimulate the apparent deadenylation and/or breakdown of TNFalpha mRNA in intact cells. Alignments of the tandem zinc finger domains from all four groups of homologous proteins have identified invariant residues as well as group-specific signature amino acids that presumably contribute to ARE binding and protein-specific activities, respectively.

Evidence that tristetraprolin is a physiological regulator of granulocyte-macrophage colony-stimulating factor messenger RNA deadenylation and stability

Deficiency of tristetraprolin (TTP), the prototype of the CCCH zinc finger proteins, results in a complex inflammatory syndrome in mice. Most aspects of the syndrome are secondary to excess circulating tumor necrosis factor (TNF)-alpha, a consequence of increased stability of TNF-alpha messenger RNA (mRNA) in TTP-deficient macrophages. TTP can bind directly to the AU-rich element in TNF-alpha mRNA, increasing its lability. Here we show that TTP deficiency also results in increased cellular production of granulocyte-macrophage colony-stimulating factor (GM-CSF) and increased stability of its mRNA, apparently secondary to decreased deadenylation. Similar findings were observed in mice also lacking both types of TNF-alpha receptors, excluding excess TNF-alpha production as a cause of the increased GM-CSF mRNA levels and stability. TTP appears to be a physiological regulator of GM-CSF mRNA deadenylation and stability. (Blood. 2000;95:1891-1899)

Phagocytic and macropinocytic activity in MARCKS-deficient macrophages and fibroblasts

Macrophages express high levels of the myristoylated, alanine-rich, C kinase substrate (MARCKS), an actin cross-linking protein. To investigate a possible role of MARCKS in macrophage function, fetal liver-derived macrophages were generated from wild-type and MARCKS knockout mouse embryos. No differences between the wild-type and MARCKS-deficient macrophages with respect to morphology (Wright's stain) or actin distribution (staining with rhodamine-phalloidin, under basal conditions or after treatment with phorbol esters, lipopolysaccharide, or both) were observed. We then evaluated phagocytosis mediated by different receptors: Fc receptors tested with IgG-coated sheep red blood cells, complement C3b receptors tested with C3b-coated yeast, mannose receptors tested with unopsonized zymosan, and nonspecific phagocytosis tested with latex beads. We also studied fluid phase endocytosis in macrophages and mouse embryo fibroblasts by using FITC-dextran to quantitate this process. In most cases, there were no differences between the cells derived from wild-type and MARCKS-deficient mice. However, a minor but significant and reproducible difference in rates of zymosan phagocytosis at 45-60 min was observed, with lower rates of phagocytosis in the MARCKS-deficient cells. Our data indicate that MARCKS deficiency may lead to slightly decreased rates of zymosan phagocytosis.

Evidence that tristetraprolin binds to AU-rich elements and promotes the deadenylation and destabilization of tumor necrosis factor alpha mRNA

Mice deficient in tristetraprolin (TTP), the prototype of a family of CCCH zinc finger proteins, develop an inflammatory syndrome mediated by excess tumor necrosis factor alpha (TNF-alpha). Macrophages derived from these mice oversecrete TNF-alpha, by a mechanism that involves stabilization of TNF-alpha mRNA, and TTP can bind directly to the AU-rich element (ARE) in TNF-alpha mRNA (E. Carballo, W. S. Lai, and P. J. Blackshear, Science 281:1001-1005, 1998). We show here that TTP binding to the TNF-alpha ARE is dependent upon the integrity of both zinc fingers, since mutation of a single cysteine residue in either zinc finger to arginine severely attenuated the binding of TTP to the TNF-alpha ARE. In intact cells, TTP at low expression levels promoted a decrease in size of the TNF-alpha mRNA as well as a decrease in its amount; at higher expression levels, the shift to a smaller TNF-alpha mRNA size persisted, while the accumulation of this smaller species increased. RNase H experiments indicated that the shift to a smaller size was due to TTP-promoted deadenylation of TNF-alpha mRNA. This CCCH protein is likely to be important in the deadenylation and degradation of TNF-alpha mRNA and perhaps other ARE-containing mRNAs, both in normal physiology and in certain pathological conditions.

Feedback inhibition of macrophage tumor necrosis factor-alpha production by tristetraprolin

Tumor necrosis factor-alpha (TNF-alpha) is a major mediator of both acute and chronic inflammatory responses in many diseases. Tristetraprolin (TTP), the prototype of a class of Cys-Cys-Cys-His (CCCH) zinc finger proteins, inhibited TNF-alpha production from macrophages by destabilizing its messenger RNA. This effect appeared to result from direct TTP binding to the AU-rich element of the TNF-alpha messenger RNA. TTP is a cytosolic protein in these cells, and its biosynthesis was induced by the same agents that stimulate TNF-alpha production, including TNF-alpha itself. These findings identify TTP as a component of a negative feedback loop that interferes with TNF-alpha production by destabilizing its messenger RNA. This pathway represents a potential target for anti-TNF-alpha therapies.

Disruption of the gene encoding the mitogen-regulated translational modulator PHAS-I in mice

PHAS-I is the prototype of a group of eIF4E-binding proteins that can regulate mRNA translation in response to hormones and growth factors. To investigate the importance of PHAS-I in the physiology of the intact animal, we disrupted the PHAS-I gene in mice. Tissues and cells derived from the knockout mice contained no detectable PHAS-I protein. A related protein, PHAS-II, and eIF4E were readily detectable in tissues from these animals, but neither appeared to be changed in a compensatory manner. Mice lacking PHAS-I appeared normal at birth. However, male knockout mice weighed approximately 10% less than controls at all ages, whereas female weights were similar to those of controls. Both males and females were fertile. Tissues from adult animals appeared to be normal by routine histological staining techniques, as were routine blood cell counts and chemistries. Fibroblasts derived from PHAS-I-deficient mouse embryos exhibited normal rates of growth and overall protein synthesis, responded normally to serum stimulation of ornithine decarboxylase activity and cell growth, and rapamycin inhibition of cell growth. Under these experimental conditions, PHAS-I is apparently not required for the normal development and reproductive behavior of female mice, but is required for normal body weight in male mice; the mechanisms responsible for this phenotype remain to be determined.

Bone marrow transplantation reproduces the tristetraprolin-deficiency syndrome in recombination activating gene-2 (-/-) mice. Evidence that monocyte/macrophage progenitors may be responsible for TNFalpha overproduction

Tristetraprolin-deficient [TTP (-/-)] mice exhibit a complex syndrome of myeloid hyperplasia, cachexia, dermatitis, autoimmunity, and erosive arthritis. Virtually the entire syndrome can be prevented by the repeated injection of anti-TNFalpha antibodies (Taylor, G.A., E. Carballo, D.M. Lee, W.S. Lai, M.J. Thompson, D.D. Patel, D.I. Schenkman, G.S. Gilkeson, H.E. Broxmeyer, B.F. Haynes, and P.J. Blackshear. 1996. Immunity. 4:445-454). In the present study, we transplanted bone marrow from TTP (-/-) and (+/+) mice into recombination activating gene-2 (-/-) mice. After a lag period of several months, marrow transplantation from the (-/-) but not the (+/+) mice resulted in the full syndrome associated with TTP deficiency, suggesting that hematopoietic progenitors are responsible for the development of the syndrome. Western blot analysis of supernatants from cultured TTP-deficient macrophages derived from the peritoneal cavity or bone marrow of adult TTP (-/-) mice, or from fetal liver, demonstrated an increased accumulation of TNFalpha after stimulation with LPS compared to control cells, and also increased accumulation of TNFalpha mRNA. This difference was not observed with cultured fibroblasts or T and B lymphocytes. These data suggest that macrophages are among the cells responsible for the effective excess of TNFalpha that leads to the pathology reported in TTP (-/-) animals, and that macrophage progenitors may be involved in the transplantability of this syndrome.

Tolerance and efficacy of subcutaneous interferon-beta administered for treatment of chronic hepatitis C

We studied tolerance to subcutaneous (s.c.) administration of 6 million units of interferon-beta (IFN-beta), given three times per week for 6 months, and its efficacy in the treatment of 15 patients with chronic hepatitis C. At the end of the treatment, alanine aminotransferase (ALT) levels were significantly reduced (p = 0.024) in all patients, and 4 (27%) had a normal ALT value. However, at the end of the study (12 months), only 1 of these 4 had a sustained response. No patient cleared hepatitis C virus (HCV) RNA completely, but the RNA could be detected only by polymerase chain reaction (PCR) in the sustained responder. Adverse side effects to the s.c. IFN-beta were infrequent. Leukocyte (p = 0.012) and platelet (p = 0.013) counts decreased significantly during treatment but did not necessitate dose modifications. Thus, although s.c. IFN-beta at the dosage used had little efficacy in the treatment of chronic hepatitis C, the excellent tolerance to the treatment suggests that the effects of higher doses should be explored.

Multicenter randomized, controlled study of intramuscular administration of interferon-beta for the treatment of chronic hepatitis C

The intramuscular administration of interferon-beta (IFN-beta) at a dosage of 6 million units three times per week for 6 months has been evaluated in 90 patients included in a multicenter, randomized, controlled trial for the treatment of chronic hepatitis C. Transaminase levels were significantly reduced in IFN-beta-treated patients (p = 0.015) and were significantly lower with respect to those of the untreated controls (p = 0.040 at 6 months). Four treated (8%) and one untreated (2.5%) patients had normal transaminase values after 6 months. At study end (12 months), three quarters of the IFN-beta-treated patients had sustained transaminase normalization, whereas the untreated case had relapsed. Hepatitis C viremia was cleared in 6 (12%) treated patients but in none of the untreated controls (p = 0.058). Side effects of IFN-beta were infrequent (a mild flu-like syndrome in < 10%, asthenia in 16%, anorexia in 8%, headaches and weight loss in 8%, and hair loss in 4%). Leukocyte and platelet counts decreased during IFN-beta treatment, but no dose modifications were necessary. Such decreases were not statistically significant when compared with the levels in the untreated controls. Intramuscular IFN-beta at the dosage used has little efficacy in the treatment of chronic hepatitis C. Because of IFN-beta tolerance, higher doses and alternate routes of injection might prove beneficial for the treatment of this disease.

[Prevalence of the genotypes of the hepatitis C virus in Spanish drug addicts with chronic hepatitis C. Spanish Group for the Study of Viral Hepatitis in HIV Positive Patients]

The hepatitis C virus (HCV) shows a wide genetic variability. The different variants of HCV have been classified into 9 types and different subtypes. Some genotypes have a characteristic geographic distribution and seem to be associated with precise ways of contagion. Serum samples from 107 spanish patients with chronic hepatitis C were studied, which were distributed as follows: 88 parenteral drug addicts (PDA) and a control group of 19 subjects made up by 4 transfused, 5 probably sexually infected and 10 with unknown contagion source (sporadic cases). HCV typing was made by means of the PCR method and later hybridization analysis with complementary probes of different types and subtypes of HCV exposed on a smooth surface (Inno-LiPA). A total to 105 (98.4%) patients had their viruses genotypes. There was more than one genotype in the same subject (co-infection) in 43.8% of cases and co-infection 1a + 1b was the most common (82.7%). While not reaching a statistic significance, co-infections were more frequent in PDA (47.1%) than in the remaining patients (27.8%). In the infected patients with only one genotype, the most common genotype was 1a, both in PDA (22.9%) and in subjects with transfusional HCV, sexual or sporadic (38.9%). In decreasing frequency came genotypes 1b (13.3%) and 3a (11.4%). Other genotypes were very uncommon (2a and 4) or were absent (2b and 5) as unique infections. In conclusion, genotypes non-1b of HCV, mainly 1a and to a lesser extent 3a, are the most common in a spanish population made up mainly by young persons with risk antecedents for HIV infection, particularly PDA. Furthermore, co-infection with HCV genotypes is frequent in this population.

Interferon alpha for the treatment of chronic hepatitis C in patients infected with human immunodeficiency virus. Hepatitis-HIV Spanish Study Group

Liver disease secondary to hepatitis C virus (HCV) infection is a rising cause of morbidity and mortality among individuals who have been infected parenterally with human immunodeficiency virus (HIV) such as injection drug users, hemophiliacs, and transfused patients. We analyzed both the efficacy of interferon (IFN) alpha therapy in these patients and the predictors of response to this agent. A total of 119 patients with chronic hepatitis C (90 of whom were infected with HIV and 29 of whom were not) were included in a multicenter, prospective, open, nonrandomized observational study. IFN-alpha was given subcutaneously in a dosage of 5 million units three times a week during a 3-month period; those patients who responded received a dose of 3 million units given subcutaneously three times a week for an additional 9 months. One hundred seven patients completed the study; the level of aminotransferases returned to normal and sera became negative (complete response) for HCV RNA in 26 (32.5%) of 80 HIV-infected patients and 10 (37.0%) of 27 non-HIV-infected patients (P = .666) after completion of the treatment. Two variables were independently associated with a response in HIV-infected patients: a CD4+ T lymphocyte count of > 500 x 10(6)/L and a baseline HCV viremia level of < 10(7) copies/mL. In the 12 months following treatment, relapses occurred in 30.8% of the HIV-infected patients and 12.5% of non-HIV-infected patients (P = .403).

Detection of circulating neoplastic cells by reverse-transcriptase polymerase chain reaction in malignant melanoma: association with clinical stage and prognosis

PURPOSE

Circulating melanoma cells can be detected in peripheral blood by means of tyrosinase mRNA amplification by reverse-transcriptase polymerase chain reaction (RT-PCR). We conducted a prospective study to evaluate the clinical significance of the presence of circulating neoplastic cells in the blood of patients with malignant melanoma (MM).

METHODS

A sensitive RT-PCR assay was used to detect tyrosinase mRNA in the peripheral blood of patients with stages I to IV melanoma. Healthy subjects or patients with other malignancies were used as negative controls.

RESULTS

Ninety-one assessable patients were included in the study. There was a statistically significant association between RT-PCR positivity and clinical stage. Circulating melanoma cells were detected in 36% of patients with localized disease (stages I and II), in 45% of patients with regional nodal involvement (stage III), and in 94% of patients with metastatic disease (stage IV) (P < .001). In stage II-III patients who were RT-PCR-positive for mRNA tyrosinase in blood, the recurrence rate and disease-free survival were significantly worse than patients who were RT-PCR-negative. In multivariate analysis, RT-PCR was an independent prognostic factor for recurrence in patients with nonmetastatic disease (P = .002).

CONCLUSION

The detection of circulating melanoma cells in peripheral blood by RT-PCR correlated with the clinical stage of patients with melanoma and was an independent prognostic factor for recurrence. Further studies are warranted to better assess the significance of this test in the evaluation of prognosis, early detection of relapse, and in monitoring the effectiveness of systemic therapy.

A pathogenetic role for TNF alpha in the syndrome of cachexia, arthritis, and autoimmunity resulting from tristetraprolin (TTP) deficiency

Tristetraprolin (TTP) is a widely expressed potential transcription factor that contains two unusual CCCH zinc fingers and is encoded by the immediate-early response gene, Zfp-36. Mice made deficient in TTP by gene targeting appeared normal at birth, but soon manifested marked medullary and extramedullary myeloid hyperplasia associated with cachexia, erosive arthritis, dermatitis, conjunctivitis, glomerular mesangial thickening, and high titers of anti-DNA and antinuclear antibodies. Myeloid progenitors from these mice showed no increase in sensitivity to growth factors. Treatment of young TTP-deficient mice with antibodies to tumor necrosis factor alpha (TNF alpha) prevented the development of essentially all aspects of the phenotype. These results indicate a role for TTP in regulating TNF alpha synthesis, secretion, turnover, or action. TTP-deficient mice may serve as useful models of the autoimmune inflammatory state resulting from chronic effective TNF alpha excess.

Epidemiology of HIV-2 infection in Spain. The HIV-2 Spanish Study Group

Human immunodeficiency virus type 2 (HIV-2) infection is endemic in West Africa, where it is responsible for many cases of AIDS. HIV-2-infected subjects have been described in other countries, mainly African immigrants, although infection in native individuals has been reported as well. The first cases of HIV-2 infection in Spain were identified in 1988. Through December 1995, 56 HIV-2 infected individuals have been diagnosed, primarily in large urban areas (23 cases in Madrid and 18 in Barcelona). All are African immigrants, except for 12 natives (21.4%), six of whom acquired the infection in endemic areas; the remaining six (2 women with numerous sexual partners and 4 homo/bisexual men) acquired the infection in Spain. Heterosexual transmission was probable in all but seven cases: five homo/bisexual males, a subject who likely acquired infection through parenteral exposure, and a child born to an HIV-2-infected mother. Nine patients (all Spanish born) have developed AIDS (16%), six of whom have died. In conclusion, HIV-2 infection is present in Spain at a low rate, and there is little evidence supporting an emerging ongoing transmission outside the population of African immigrants.

[The treatment of chronic hepatitis C with interferon in patients infected with the human immunodeficiency virus. The Spanish Group for the Study of Viral Hepatitis in HIV+ Patients]

BACKGROUND

Alfa-interferon (aIFN) is widely recommended for the treatment of chronic hepatitis C (CHC). Hepatitis C virus (HCV) infection is very common in injecting drug users (IDUs), which in Spain represent the large number of HIV-infected persons. Interaction between human immunodeficiency virus (HIV) and HCV in coinfected patients might accelerate the clinical course of HCV-associated liver disease. The efficacy and safety of aIFN therapy in HIV-infected patients with CHC is not well known.

PATIENTS AND METHODS

In a multicenter, prospective, open, non randomized and partially controlled study, we compared the efficacy and safety of aIFN therapy in 119 patients with CHC, of whom 90 were HIV-positive and 29 HIV-negative. Interferon was started at 5 mega U tiw for 3 months, followed in responders by 3 megaU tiw for additional 9 months.

RESULTS

One hundred seven patients completed the study. A normalization of the aminotransferase values at the end of treatment (complete response, CR) was observed in 26/80 (32.5%) HIV-positive and 10/27 (37.0%) HIV-negative individuals (p = 0.666). Relapses at 12 months of stopping aIFN were seen in 30.8% of HIV-positive subjects and 12.5% of HIV-negatives (p = 0.403). Side effects were uncommon and did not have severity; only one patient required to stop the medication. However, 3 HIV-positive subjects treated with aIFN (3.5% of them) showed an irreversible fall of CD4+ T-cells below half the baseline values.

CONCLUSION

HIV-infected patients with CHC seems to respond to aIFN with a similar rate than HIV-negatives. Moreover, the drug is similarly well tolerated in both groups of patients, although a fall of CD4+ T-cells is an unusual side effect of particular relevance observed in HIV-infected patients.

Characterization and purification of a protein kinase C substrate in human B cells. Identification as lymphocyte-specific protein 1 (LSP1)

Incubation of B-chronic lymphocytic leukemia (B-CLL) cells with phorbol esters resulted in the phosphorylation of two major PKC substrates, MARCKS (myristoylated, alanine-rich C kinase substrate) and MRP (MARCKS-related protein), and of a third protein, with an apparent m.w. of 60,000 that was the most prominent protein kinase C substrate in these cells. p60 phosphorylation was time and PMA dose dependent, and was induced by cell-permeable diacylglycerol, but not by inactive phorbol esters. Two-dimensional electrophoretic analysis of the protein phosphorylation pattern from the B cell line CESS demonstrated the identity between the p60 protein expressed in this cell line and that expressed in B-CLL cells. p60 was purified from CESS cells and peptide microsequencing of this protein revealed that it was lymphocyte-specific protein 1 (LSP1), that is here characterized as the most prominent protein kinase C substrate in B cells.

Characterization and purification of a protein kinase C substrate in human B cells. Identification as lymphocyte-specific protein 1 (LSP1)

Incubation of B-chronic lymphocytic leukemia (B-CLL) cells with phorbol esters resulted in the phosphorylation of two major PKC substrates, MARCKS (myristoylated, alanine-rich C kinase substrate) and MRP (MARCKS-related protein), and of a third protein, with an apparent m.w. of 60,000 that was the most prominent protein kinase C substrate in these cells. p60 phosphorylation was time and PMA dose dependent, and was induced by cell-permeable diacylglycerol, but not by inactive phorbol esters. Two-dimensional electrophoretic analysis of the protein phosphorylation pattern from the B cell line CESS demonstrated the identity between the p60 protein expressed in this cell line and that expressed in B-CLL cells. p60 was purified from CESS cells and peptide microsequencing of this protein revealed that it was lymphocyte-specific protein 1 (LSP1), that is here characterized as the most prominent protein kinase C substrate in B cells.

Efficacy and safety of alpha-interferon treatment for chronic hepatitis C in HIV-infected patients. HIV-Hepatitis Spanish Study Group

The efficacy and safety of recombinant alpha-interferon (IFN) therapy for chronic hepatitis C (CHC) was assessed in 57 HIV-infected individuals with CD4+ T cells above 200/mm3 and compared to the response obtained in 21 HIV-negative patients with CHC. IFN 5 megaU was given three times a week subcutaneously for 3 months. In responding patients, IFN 3 megaU three times a week was additionally administered for 9 months. After 8 months follow-up in HIV-infected patients, 38% (22/57) achieved normal (complete response, CR) alanine aminotransferase (ALT) values. Partial response (PR) was seen in 21% (12/57), and 40% (23/57) did not respond. Patients with CD4+ cells above 500/mm3 achieved CR in 58% (14/24) of cases compared to 24% (8/33) among those having a lower CD4+ count (P < 0.01). Females attained CR in 60% (9/15) of cases, and men in only 30.9% (13/42) (P < 0.01). No serious side effects or opportunistic infections were observed during the study period. However, three (5.2%) patients showed a dramatic fall in total CD4+ T cell count after beginning IFN therapy. Among 21 HIV-negative patients, after 8 months follow-up, CR was achieved in 10 (47%), PR in four (19%), and seven (33%) did not respond. We concluded that IFN therapy seems to be well tolerated and useful in HIV-infected patients suffering CHC. The rate of CR was not significantly different compared to that observed in HIV-negative patients (38% vs. 47%), relative risk (RR) = 0.67 (0.19-2.37).(ABSTRACT TRUNCATED AT 250 WORDS)

Phosphorylation of the MARCKS family of protein kinase C substrates in human B chronic lymphocytic leukemia cells

Incubation of B chronic lymphocytic leukemia (B-CLL) cells with phorbol esters resulted in the phosphorylation of three Triton-soluble, heat-stable, acidic proteins with apparent M(r) of 80 KDa, 60 KDa and 43 KDa. The characteristics of the three proteins suggested that they could be related to the myristoylated, alanine-rich, C-kinase substrate (MARCKS). p80 was immunoprecipitated with an antibody against the N-terminal peptide of MARCKS. p43 co-migrated with mouse MRP/Mac-MARCKS (MARCKS-related protein). p60 is the most prominent substrate of protein kinase C in B-CLL cells.

[Human immunodeficiency virus type 2 infection in 2 seamen of the northwest of Spain]

The first two cases of HIV-2 infection in autoctonous Spanish subjects are presented. Two sailors (62 and 42 years of age) of Galician origin who travelled to east African countries are reported. The epidemiologic, clinico-evolutive characteristics--with manifestations similar to HIV-1 infection (oral candidiasis and villous leukoplasia)--, and therapeutic response to zidovudine are described. The risk of HIV-2 infection in sailors travelling to Africa and the absence of opportunistic infections in a period of at least 6 to 11 years following infection despite CD4+ lymphocytes being under 0.200 x 10(9)/l, are of note.

Oral administration of vanadate to diabetic rats restores liver 6-phosphofructo-2-kinase content and mRNA

Vanadate and insulin were administered to diabetic (streptozotocin) rats to compare their effects on the activity and mRNA content of 6-phosphofructo-2-kinase and L-type pyruvate kinase in the liver. The activity of 6-phosphofructo-2-kinase in livers of diabetic rats was about 40% of that found in normal rats. A similar decrease was found for 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase content, measured by immunoprecipitation, and for mRNA, measured by hybridization of Northern blots. Administration of vanadate to the diabetic rats led to a progressive recovery of 6-phosphofructo-2-kinase activity, and 6-phosphofructo-2-kinase/fructose- 2,6-bisphosphatase content and mRNA. This recovery, which was complete after 15 days of oral treatment, was also obtained after 60 h of insulin administration. L-type pyruvate kinase activity and mRNA were also decreased by about 70% in livers of diabetic rats. Both parameters normalized after 15 days of vanadate treatment, whereas insulin administration (60 h) raised L-pyruvate kinase mRNA three-fold above control values. Oral treatment for 15 days with vanadate can thus mimic the effect of insulin on both pyruvate kinase and 6-phosphofructo-2-kinase/fructose-2,6- bisphosphatase in livers of diabetic rats.

Erythrocyte fructose 2,6-bisphosphate content in congenital hemolytic anemias

We have investigated the levels of fructose 2,6-bisphosphate and its synthesizing enzyme 6-phosphofructo-2-kinase in red blood cells from different congenital anemias. Fructose 2,6-bisphosphate concentration and 6-phosphofructo-2-kinase activity are markedly influenced by the number of reticulocytes in all the cases studied with the exception of homozygous pyruvate kinase deficiency, where no correlation was observed with the percentage of reticulocytes.