Human cardiac multipotent adult stem cells in 3D matrix: new approach of tissue engineering in cardiac regeneration post-infarction.

Myocardial infarction is the leading cause of morbidity and mortality in developed countries. It causes a left ventricular dysfunction, mainly due to the loss of functional tissue, resulting in heart failure. New therapies are being developed, using a tissue engineering approach, with the ultimate goal of restoring cardiac function by regenerating and repairing the damaged myocardium. In the present study we investigated the behaviour of a specific population of c-kit positive human cardiac stem cells, called Multipotent Adult Stem Cells (MASCs), grown within three-dimensional collagen scaffolds (3D), to establish whether they could be used in post-infarction cardiac regeneration. We also evaluated the expression levels of the Granulocyte Macrophage-Colony Stimulating Factor Receptor (GM-CSFR) and endoglin, a component of the Transforming Growth Factor beta (TGF-ß) receptor complex. Finally, we also evaluated the expression of the α2ß1integrin. MASCs cultured within 3D collagen matrices are able to proliferate and migrate even in the absence of chemotactic agents and express high levels of factors involved in cell proliferation and migration, such as GM-CSFRα chain and integrins. They therefore represent a promising approach to tissue engineering aimed to restore cardiac function. Our results also suggest a role of GM-CSF in cell proliferation, while TGF-ß does not seem to be relevant.

High incidence of MTHFR, CBS, and MTRR polymorphisms in vitiligo patients. Preliminary report in a retrospective study.

OBJECTIVE: Vitiligo is a multifactorial polygenic disorder with a complex pathogenesis. It is related to both genetic and no genetic factors. The role of genetics is currently studied with several analytical approaches, such as genetic linkage, candidate gene association studies, genome-wide association studies (GWAS), deep DNA re-sequencing and gene expression studies. To date, there are no genetic traits directly related to vitiligo pathogenesis. PATIENTS AND METHODS: 43 cases of vitiligo patients and 30 healthy donors recruited as control, were screened by assaying the biochemical molecules involved in the self-cells cytotoxicity (haptoglobin and homocysteine) and candidate genes involved in the regulatory process of the re-methylation cycles and transsulfuration. Candidate genes and their polymorphisms screened are methylene-tetrahydrofolate-reductase (MTHFR) C677T and A1298C; cystathionine-beta-synthase enzyme (CBS) I278T and Ins68bp; and methionine-synthase-reductase (MTRR) A66G. RESULTS: A peculiar genetic profile in vitiligo patients are defined: 11.6% of vitiligo patients shown polymorphic variant MTHFR 677TT vs. 3.3% of healthy donor MTHFR 677CC profile (p=0.0017); 14.0% of vitiligo patients shown CBS polymorphic variant 278TT vs. 3.3% of healthy donor 278II profile (p=0.0012); and 11.6% of vitiligo patients shown MTRR 66GG vs. 3.3% of healthy donor MTRR 677AA profile (p>0.0001). CONCLUSIONS: This is the first study reporting the correlation between the polymorphic status of MTHFR C677T, CBS I278T, and MTRR A66G and vitiligo. The genetic screening of these polymorphisms could be useful for early detection of the inheritance risk factor in a subject carrying relatives with vitiligo. Although these data could suggest a kind of dysregulation, genetically based, of thiols production mechanisms. Based on these results, we have not been able to get hypothesis about the putative pathogenesis of vitiligo, and the precise cause remains unclear.

Effect of repeated oral administration of BY 1023/SK&F 96022--a new substituted benzimidazole derivative--on pentagastrin-stimulated gastric acid secretion and pharmacokinetics in man.

Pentagastrin stimulated gastric secretion was measured in 12 healthy male subjects after repeated once daily oral administration of 20 and 40 mg BY 1023/SK&F 96022--a new substituted benzimidazole derivative. Twenty milligrams inhibited acid output compared with placebo by 24% (2.5-3.5 h) and 26% (24.5-25.5 h) after the first oral intake. Inhibition increased to 56% and 50%, respectively, after the seventh oral dose. Forty milligrams inhibited acid output by a mean of 51% (2.5 to 3.5 h) and 52% (24.5-25.5) after the first oral intake. After the seventh dose mean inhibition rose to 85% and 66%, respectively. The drug was well tolerated, no drug-related changes in clinical laboratory, ECG, heart rate and blood pressure were observed. Fasting gastrin serum concentrations tended to increase with both doses, the mean values being within the normal range. AUC, Cmax and t1/2 of the drug after repeated oral intake were not significantly different when compared with a single dose at either 20 mg or 40 mg.

Comparison of Mycobacterium avium isolates from Greek AIDS and human immunodeficiency virus-negative patients by pulsed-field gel electrophoresis.

OBJECTIVE: To compare the chromosomal types of Mycobacterium avium strains infecting HIV-negative and AIDS patients in Greece. METHODS: In total, 41 Mycobacterium avium isolates, 23 from AIDS and 18 from HIV-negative patients, were compared by pulsed-field gel electrophoresis of genomic DNA after XbaI digestion. The majority (87%) of AIDS isolates were from disseminated infection, while the majority (61%) of HIV-negative isolates were from children with cervical lymphadenitis. RESULTS: Pulsed-field gel electrophoresis classified strains whose electrophoretic patterns were at least 85% similar into three clusters, A (four isolates), B (12 isolates), and C (15), while 10 isolates remained outside of these clusters. There was no statistically significant correlation of any PFGE cluster with a specific patient group. Within each patient group, no significant correlation of PFGE type with time, place of residence or, in the case of AIDS patients, hospital attended was observed. CONCLUSIONS: Genotypic similarities between isolates responsible for disseminated infection in AIDS patients and lymphadenitis in HIV-negative children suggest that related strains, possibly from an environmental source, cause both types of infections.

Molecular markers for the investigation of Mycobacterium gordonae epidemics.

Mycobacterium gordonae was isolated as a light growth from bronchoalveolar aspirates from nine patients over 12 months. All patients were in one hospital, and had been bronchoscoped for suspected malignancy. None of the patients had symptoms or radiographic findings of mycobacterial infection. The isolates were characterized by biochemical tests and molecular hybridization. Random amplified polymorphic DNA analysis (RAPD) was used to test whether the strains had a common origin. All the isolates generated four to eight fragments, and almost all presented distinct RAPD patterns. Antimicrobial resistance patterns to six agents confirmed that the isolates were unrelated. Thus epidemiologically unrelated strains of M. gordonae can exist as contaminants in the same department over a relatively short time frame. RAPD analysis is easy to perform, gives rapid results, and can be used for epidemiological analysis of M. gordonae isolates.

Evaluation of Propineb, a dithiocarbamate pesticide, in the mouse-sperm morphology assay.

Propineb, a dithiocarbamate fungicide, was studied by using the sperm morphology assay in (C57BL6 male X C3H female) F1 mice. At all dose levels, no statistically significant increase in the percentage of sperm abnormalities was observed. Methyl methanesulfonate (MMS) and 2-acetylaminofluorene (2-AAF), which were tested as positive controls, induced a dose-effect-related increase in teratospermia.

Dithiocarbamate pesticides: activity of Propineb in the micronucleus test in mice.

The possible clastogenic activity of Propineb, Propineb technical grade and of its main metabolite, propylene-thiourea (PLTU), was investigated by the micronucleus test in mice according to Schmid. No statistically significant increase in the percentage of micronuclei was observed at any of the tested doses of the above compounds. As positive controls, dose-effect curves were constructed for methyl methanesulfonate (MMS) and mitomycin C (MMC).

Biological availability of mutagenic compounds adsorbed onto diesel exhaust particulate.

Diesel particles were collected from the exhaust of a VW Golf diesel car by electrostatic precipitation. The particulate and its DCM extract were highly mutagenic in the Salmonella/microsome test in the presence and absence of metabolic activation; the highest response was observed with TA98 and TA1538 tester strains. The biological availability of particulate-associated mutagenic compounds was demonstrated by administering powder to rats and assaying, in vitro, the urine excreted within 24 h after treatment. The highest activity was obtained with TA98 in the presence of metabolic activation. Typical dose-effect responses were evident in urine of animals treated by all the administration routes tested (i.p., s.c. and per os), both in the presence and absence of a suspending vehicle. Concentration of mutagenic compounds present in urine of treated animals could be achieved by chromatography on Amberlite XAD-2 and XAD-7 resins. This study provides direct evidence for bioavailability to animal tissues of mutagens adsorbed onto diesel particulate, although part of the activity might be ascribed to nitroaromatic compounds formed during the collection of the powder. The present study is part of a more comprehensive work on diesel exhaust particulate, and results have to be considered in this light before any final conclusion can be drawn.

Effect of DNOC, Ferbam and Imidan exposure on mouse sperm morphology.

DNOC, Ferbam and Imidan were tested in (C3H X C57BL/6) F1 mice to assess their potential testicular toxicity. Chemicals were administered i.p. and per os at different doses for 5 consecutive days. After 35 days the testicular was toxicity was evaluated by measuring the testicular weights, the sperm counts and the percentage of abnormal sperm. DNOC and Imidan failed to induce teratospermia in mice treated by both routes of administration. Conversely Ferbam induced a statistically significant increase in teratospermia only following per os administration to mice at a dose of 1000 mg/kg b.w./day. These data indicate that per os administration of Ferbam succeeded in producing active metabolites able to interfere with the differentiation process of spermatogenic cells.

Induction of sperm abnormalities in mice by ifosfamide and trofosfamide.

The antitumor drugs ifosfamide (IF) and trofosfamide (TF) were evaluated for their capability to induce sperm abnormalities in (C3H X C57BL/6)F1 mice. A statistically significant increase in teratospermia was observed at the 35th day after 5 daily consecutive intraperitoneal injections of the drugs at doses of 25, 50, 100 mg/kg b.w. of TF and 100 mg/kg b.w. of IF. Thus, IF and TF are able to interfere with the differentiation process of spermatogenic cells.

[Gastrointestinal tolerance of 30 mg versus 300 mg acetylsalicylic acid daily. An endoscopically controlled double-blind study of healthy subjects]. / Gastroduodenale Verträglichkeit von 30 mg versus 300 mg Acetylsalicylsäure täglich. Eine endoskopisch kontrollierte Doppelblindstudie an gesunden Probanden.

Acetylsalicylic acid (ASS) is increasingly used in the prevention of cardiovascular diseases. In recent years daily ASS-doses (100 to 300 mg) have been given for this indication. Studies with still lower ASS-doses (f. i. 30 mg daily) are the focus of ongoing clinical trials. In a randomized double-blind study we have evaluated the gastroduodenal tolerability of 30 mg ASS and 300 mg ASS daily in 20 healthy volunteers using upper GI-endoscopy. Both ASS-dosages have been taken for a period of four weeks. Endoscopic controls were performed at entry and repeated after seven, 14 and 28 days of treatment. 30 mg ASS daily did not induce significant gastroduodenal damages during the whole treatment period in contrast to 300 mg ASS daily (p less than 0.05). The lesions score under 300 mg ASS on day 7 and 28 was almost identical. Our data suggest that extremely low doses of ASS are almost harmless to the human gastroduodenal mucosa. No adaptive phenomena occur during a 28 days treatment with 300 mg ASS daily.

Neuroglobin upregulation induced by 17ß-estradiol sequesters cytocrome c in the mitochondria preventing H2O2-induced apoptosis of neuroblastoma cells.

The sex steroid hormone 17ß-estradiol (E2) upregulates the levels of neuroglobin (NGB), a new neuroprotectant globin, to elicit its neuroprotective effect against H(2)O(2)-induced apoptosis. Several mechanisms could be proposed to justify the NGB involvement in E2 prevention of stress-induced apoptotic cell death. Here, we evaluate the ability of E2 to modulate the intracellular NGB localization and the NGB interaction with mitochondrial cytochrome c following the H(2)O(2)-induced toxicity. Present results demonstrate that NGB is expressed in the nuclei, mitochondria, and cytosol of human neuroblastoma SK-N-BE cells. E2, but not H(2)O(2) treatment of SK-N-BE cells, reallocates NGB mainly at the mitochondria and contemporarily reduces the number of apoptotic nuclei and the levels of cleaved caspase-3. Remarkably, the E2 treatment strongly increases NGB-cytochrome c association into mitochondria and reduces the levels of cytochrome c into the cytosol of SK-N-BE cells. Although both estrogen receptors (ERα and ERß) are expressed in the nucleus, mitochondria, and cytosol of SK-N-BE cells, this E2 effect specifically requires the mitochondrial ERß activity. As a whole, these data demonstrate that the interception of the intrinsic apoptotic pathway into mitochondria (i.e., the prevention of cytochrome c release) is one of the pivotal mechanisms underlying E2-dependent NGB neuroprotection against H(2)O(2) toxicity.

17ß-Oestradiol anti-inflammatory effects in primary astrocytes require oestrogen receptor ß-mediated neuroglobin up-regulation.

Neuroglobin (Ngb), so named after its initial discovery in brain neurones, has received great attention as a result of its neuroprotective effects both in vitro and in vivo. Recently, we demonstrated that, in neurones, Ngb is a 17ß-oestradiol (E(2) ) inducible protein that is pivotal for hormone-induced anti-apoptotic effects against H(2) O(2) toxicity. The involvement of Ngb in other brain cell populations, as well as in other neuroprotective effects of E(2) , is completely unknown at present. We demonstrate Ngb immunoreactivity in reactive astrocytes located in the proximity of a penetrating cortical injury in vivo and the involvement of Ngb in the E(2) -mediated anti-inflammatory effect in primary cortical astrocytes. Upon binding to oestrogen receptor (ER)ß, E(2) enhances Ngb levels in a dose-dependent manner. Although with a lesser degree than E(2) , the pro-inflammatory stimulation with lipopolysaccharide (LPS) also induces the increase of Ngb protein levels via nuclear factor-(NF)κB signal(s). Moreover, a negative cross-talk between ER subtypes and NFκB signal(s) has been demonstrated. In particular, ERα-activated signals prevent the NFκB-mediated Ngb increase, whereas LPS impairs the ERß-induced up-regulation of Ngb. Therefore, the co-expression of both ERα and ERß is pivotal for mediating E(2) -induced Ngb expression in the presence of NFκB-activated signals. Interestingly, Ngb silencing prevents the effect of E(2) on the expression of inflammatory markers (i.e. interleukin 6 and interferon γ-inducible protein 10). Ngb can be regarded as a key mediator of the different protective effects of E(2) in the brain, including protection against oxidative stress and the control of inflammation, both of which are at the root of several neurodegenerative diseases.

In-vitro activity of ciprofloxacin against clinical isolates of mycobacteria resistant to antimycobacterial drugs.

The activity of ciprofloxacin against 42 clinical isolates of mycobacteria was studied in vitro by the 1% standard proportion method on Lowenstein-Jensen medium. Ciprofloxacin was found active against all strains of Mycobacterium tuberculosis sensitive to streptomycin, isoniazid, ethambutol and rifampicin. The MIC of ciprofloxacin was 3.2 mg/l. This concentration of ciprofloxacin was sufficient to inhibit almost all strains showing intermediate sensitivity or resistance to one or more of the above agents. The same phenomenon was also observed with the atypical isolates.

[Protective effect of an antacid against acetylsalicylic acid]. / Schutzwirkung eines Antazidums gegenüber Acetylsalicylsäure.

The protective action of an magnesium-aluminum-antacid (Mucal-Gel) against acute doses of acetylsalicylic acid (ASA) was studied in healthy subjects (n = 30) by a double-blind cross-over method. The severity of the lesion was determined by endoscopy. In the corresponding placebo experiments, severe lesions of the gastroduodenal mucosa were seen after administration of 1500 mg ASA. These lesions could be prevented only in the presence of high doses of the antacidum mixture. It is concluded from these studies that protective actions against ASA can be achieved only if the intragastric pH-level is adequately raised above 3.5 and higher.

Comparison of in vitro activities of eight new beta-lactam compounds against cephalothin-resistant Enterobacteriaceae from hospital patients.

The in vitro antibacterial activity of eight newer beta-lactam antibiotics (mecillinam, piperacillin, mezlocillin, cefoxitin, cefotaxime, moxalactam, ceftriaxone and ceftazidime) was determined against 87 cephalothin-resistant strains of Enterobacteriaceae isolated during 6 months in a general hospital. Ceftriaxone, cefotaxime, moxalactam and ceftazidime proved to be highly active; only a minority of strains required higher concentrations than 0.125 microgram/ml for inhibition of growth. Cefoxitin, mecillinam, mezlocillin and piperacillin were less active. Mecillinam displayed greater efficacy against Escherichia coli, Klebsiella and Enterobacter spp., while the same was the case for piperacillin against Proteus mirabilis and Serratia marcescens, and for cefoxitin against indole-positive Proteus spp. The production of beta-lactamase was correlated with a reduced activity of mecillinam, mezlocillin and piperacillin but not of cefoxitin or the other beta-lactamase-stable cephalosporins. However, some strains, mainly those of Proteus, Enterobacter and Serratia, though resistant to mecillinam, mezlocillin and piperacillin did not produce beta-lactamases. This observation might indicate that ceftriaxone, moxalactam, cefotaxime and ceftazidime, besides their indifference to beta-lactamases, are characterized also by a high degree of intrinsic activity.

[Endoscopic studies of gastroduodenal tolerance of 100 mg versus 500 mg acetylsalicylic acid daily: a randomized double-blind study with healthy probands]. / Endoskopische Untersuchungen zur gastroduodenalen Verträglichkeit von 100 mg versus 500 mg Azetylsalizylsäure täglich: Eine randomisierte Doppelblindstudie an gesunden Probanden.

Acetylsalicylic acid (ASS) is increasingly used in the prevention of cardiovascular diseases. In recent years lower daily ASS-doses (100-300 mg) have been given for this indication. However, only marginal knowledge is available about the upper GI-tolerability of ASS in this dosage regiment. In a randomized double-blind study we have evaluated the gastroduodenal tolerability of 100 mg ASS and 500 mg ASS daily in 20 healthy volunteers using upper GI-endoscopy. Both ASS-dosages have been taken over a period of 4 weeks. Endoscopic controls were performed at entry and repeated after 7, 14 and 28 days of treatment. 100 mg ASS daily induced during the whole period significant less gastroduodenal damages than 500 mg ASS daily (p less than 0.05). The lesion score of both groups on day 7 and day 28 were almost identical. Our data suggest that even low doses of ASS (100 mg daily) produced gastroduodenal injuries and that no adaptative phenomena did occur during the treatment period.

[Gastroduodenal tolerance of tenoxicam versus diclofenac-Na: an endoscopy double-blind controlled study in healthy probands]. / Gastroduodenale Verträglichkeit von Tenoxicam versus Diclofenac-Na: Eine endoskopisch-kontrollierte Doppelblindstudie an gesunden Probanden.

The gastroduodenal tolerability of tenoxicam vs diclofenac-Na was evaluated in a double-blind, parallel group study in 36 healthy male volunteers. The doses used were 20 mg tenoxicam vs 100 mg diclofenac-Na in a retard formulation daily over a period of 14 days. Gastric tolerability was assessed by using upper endoscopy. Gastroscopy was performed at base-line after the dosing period of 14 days and again after a follow-up period of 14 days without any treatment. The mucosal lesions were scored using modified Lanza criteria. In comparison to diclofenac-Na, tenoxicam was significantly better tolerated after a 14-day dosing period (mean gastric score: tenoxicam: 1.3 +/- 0.7; diclofenac-Na: 2.2 +/- 1.1 p = 0.0143). Both treatment groups had comparable scores at base-line and post-study assessments. Tenoxicam and diclofenac-Na were generally well tolerated. Only two volunteers reported intermittent lack of appetite, heartburn, and a feeling of pressure in the stomach. In summary, tenoxicam given as a 20 mg single oral morning dose over a 14-day period was significantly better tolerated than diclofenac 100 mg with regard to gastroduodenal mucosal damage.