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Biomedical subjects

F Gruber

Publications and source records attributed to F Gruber.

At least 37 records · Page 2Linked to original sources
PubMed2000

Skrljevo disease--two centuries of history.

Skrljevo disease, also called Rijeka (Fiume) or Grobnik disease, by some physicians was first identified in the village of Skrljevo in Croatia in 1790. From texts dating back to the beginning of the 19th century it is clear that it was a non-venereal (endemic) form of syphilis and represented a great calamity for the local people and a problem for the physicians. The disease was considered by some to be lepra, scurvy, scabies or others. The occurrence of the disease in the region around Rijeka was closely associated with the poor socioeconomic conditions present at that time in the region. It is interesting to note that many of the greatest physicians of the time such as Alibert, Frank, Hebra, Sigmund were acquainted with the disease and dealt with it in their writings. This paper gives a brief chronology of the major political events in the region since that time, underlying the measures used in fighting the disease.

Croatia↗
PubMed2000

A systematic and quantitative analysis of PCR template contamination.

A quantitative and systematic analysis is provided for ubiquitously present template DNA interfering with the quantification of human DNA by PCR. Two sources contributing to DNA background were identified. The first one is interpreted as DNA present in chemicals and on equipment and the second as caused by operator handling. The amounts were equivalent to 2.5 and 8.9 pg per mL of sample, and the estimated frequencies of contamination were 65 and 35%, respectively, resulting in an effective limit of detection of 17.4 pg/mL. Below this level--named effective laboratory background--a result could not be considered as authentic. Knowledge of these parameters is important for laboratories that analyze minute amounts of human DNA by PCR for purposes such as quantification, typing, and sequencing.

DNA Fingerprinting↗
PubMed1999

Highly efficient induction of protective immunity by a vaccinia virus vector defective in late gene expression.

Vaccinia viruses defective in the essential gene coding for the enzyme uracil DNA glycosylase (UDG) do not undergo DNA replication and do not express late genes in wild-type cells. A UDG-deficient vaccinia virus vector carrying the tick-borne encephalitis (TBE) virus prM/E gene, termed vD4-prME, was constructed, and its potential as a vaccine vector was evaluated. High-level expression of the prM/E antigens could be demonstrated in infected complementing cells, and moderate levels were found under noncomplementing conditions. The vD4-prME vector was used to vaccinate mice; animals receiving single vaccination doses as low as 10(4) PFU were fully protected against challenge with high doses of virulent TBE virus. Single vaccination doses of 10(3) PFU were sufficient to induce significant neutralizing antibody titers. With the corresponding replicating virus, doses at least 10-fold higher were needed to achieve protection. The data indicate that late gene expression of the vaccine vector is not required for successful vaccination; early vaccinia virus gene expression induces a potent protective immune response. The new vaccinia virus-based defective vectors are therefore promising live vaccines for prophylaxis and cancer immunotherapy.

Animals↗
PubMed1998

Precise quantitation of human parvovirus B19 DNA in biological samples by PCR.

An application of a quantitative PCR-based method was developed for the detection of human parvovirus B19 DNA. The procedure was characterised according to guidelines for the validation of analytical procedures. Furthermore, the reliability was demonstrated by the correct quantitation of samples of an international collaborative study. This application might be useful for studies focussed on removal and/or inactivation procedures of human parvovirus B19 as well as for general screening purposes of biological materials.

Base Sequence↗
PubMed1998

Azithromycin compared with minocycline in the treatment of acne comedonica and papulo-pustulosa.

This open study was conducted in 72 outpatients with acne vulgaris, to compare the clinical efficacy and tolerability of azithromycin and minocycline. Azithromycin was administered as a single oral dose (500 mg/day) for 4 days in four cycles every 10 days and minocycline was administered 100 mg daily for 6 weeks. Improvement was assessed 6 weeks after initiation of treatment with a four-graded scale. A satisfactory clinical response was observed in 75.8% of the patients treated with azithromycin and in 70.5% of those treated with minocycline. There were no significant differences between these two acne treatments in terms of reduction of the number of lesions (p> 0.05). Both agents were well tolerated and mild side effects were reported in 10.3% of azithromycin and 11.7% of minocycline treated patients. We conclude that azithromycin is at least as clinically effective and well tolerated as minocycline as treatment of facial comedonic and papulopustular acne.

Acne Vulgaris↗
PubMed1997

Comparative trial of azithromycin and ciprofloxacin in the treatment of gonorrhea.

This single-blind (investigator) comparative study was designed to determine the efficacy and tolerability of 1 g of azithromycin vs 500 mg of ciprofloxacin both given as a single oral dose in patients with gonorrhea, who were constantly on the move. One hundred eight patients (59 men and 49 women) with clinically suspected gonococcal infection, confirmed by Gram-stain and culture, were enrolled. Data of 50 patients treated with azithromycin and 51 with ciprofloxacin were evaluable for efficacy and tolerability at the end of the study. After 2 weeks clinical and microbiological cure rates were 96.0% (48 out of 50) for the patients treated with azithromycin and 92.15% (47 out of 51) for the patients treated with ciprofloxacin (p > 0.05). Adverse reactions were reported in 5 patients treated with azithromycin and 6 with ciprofloxacin. In conclusion, 1 g azithromycin is at least as clinically and microbiologically effective and well tolerated as 500 mg of ciprofloxacin in the treatment of gonococcal infections. The drug is particularly useful for sailors and people constantly on the move.

Administration, Oral↗
PubMed1997

Postcoital fixed drug eruption in a man sensitive to trimethoprim-sulphamethoxazole.

We describe a 34-year-old patient with a probable fixed drug eruption caused by trimethoprim-sulphamethoxazole, having developed the eruption after sexual intercourse with his wife, who was taking the drug. The patient was known to be allergic to trimethoprim-sulphamethoxazole by history, and the lesion then recurred at the same site when the drug was administered orally to his wife. To the best of our knowledge, this is the first report describing postcoital fixed drug eruption. Physicians should thus be aware of unusual and atypical forms of fixed drug eruption. Fixed drug eruption (FDE) is an unusual form of adverse drug reaction, in which one or more lesions appear in precisely the same place or places each time the precipitating drug is administered. The entity was first described by Bourns in 1889, but Brocq then coined the name some years later. FDE may occur anywhere on the skin or mucous membranes, but more frequently occurs on the genitalia and lips. Lesions are usually sharply demarcated patches which quickly become urticarial and sometimes vesicular in the centre. Itching or burning may also be present. Lesions generally leave prolonged postinflammatory hyperpigmentation. The exact pathogenesis of FDE has not been determined, but recent reports have underlined the importance of T lymphocytes, mast cells, keratinocytes and cytokines in the origin of the lesions. We now report a case of FDE apparently caused by trimethoprim-sulphamethoxazole in a male after intercourse with his wife, who was taking the drug. Such FDE, caused by contact with a drug seemingly present in the vaginal fluid, has not been previously described in the literature as far as we know.

Adult↗
PubMed1996

Specific quantitation of genomic DNA in the femtogram range by amplification of repetitive sequences.

An assay was developed to specifically quantitate concentrations as low as 50 fg/ml genomic DNA based on the amplification of repetitive sequences. Reliable results were obtained by using internal standard molecules which were coextracted, coamplified, and coanalyzed with the nucleic acids of interest. Amplification was performed by the polymerase chain reaction in the presence of fluorescent dye-labeled primers followed by quantitation of fluorescence derived from the reaction products after separation by PAGE. Based on the known amount of added internal standard molecules and the intensities of the fluorescence of the reaction products, the primary results of the assay were obtained as copies per milliliter of sample. These were converted into mass units of DNA by applying an experimentally determined conversion factor. Chicken DNA has been used as an example for genomic DNA, and the sequences amplified were CR1 repetitive elements. This type of assay may be applied in cases where a sensitive and precise quantitation of genomic DNA is required, such as in the quality control of biological products.

Animals↗
PubMed1996

Cloning and characterisation of genes (pkc1 and pkcA) encoding protein kinase C homologues from Trichoderma reesei and Aspergillus niger.

Oligonucleotides, designed on the basis of conserved flanking amino acid sequence segments within the catalytic domain of eukaryotic protein kinase C (PKC) proteins, were used as primers for polymerase chain reactions to amplify a 427-bp chromosomal DNA fragment from the filamentous fungus Trichoderma reesei. This fragment was then used to isolate genes encoding PKC homologues of T. reesei and Aspergillus niger (pkc1 and pkcA, respectively). The genes contain six (T. reesei) and eight (A. niger) introns, which exhibit notable conservation in position with those found in the corresponding Schizosaccharomyces pombe pkc1+ and Drosophila melanogaster dPKC53Ebr genes. A single 4.2-kb transcript was detected in Northern analyses. The deduced PKC1 (T.reesei, 126 kDa) and PKCA (A. niger, 122 kDa) amino acid sequences reveal domains homologous to the C1 and C3/C4 domains of PKC-related proteins, but lack typical Ca(2+)-binding (C2) domains. Both contain a large, extended N-terminus, which shares a high degree of similarity with the corresponding regions of Saccharomyces cerevisiae PKC1 and S. pombe pkc1+ and pkc2+ proteins, but which is not present in PKCs of Dictyostelium or higher eukaryotes. This extended region can be divided into three subdomains; the N-terminal one contains a hydrophobic helix-turn-helix motif, whereas the C-terminal one contains potential targets for proteolytic processing. A polyclonal antiserum raised against the pseudosubstrate-binding domain of PKC1 recognizes in T. reesei a 115-120 kDa protein in Western blots. Expression of pkc1 cDNA in insect cells directs the synthesis of a PKC1 protein of similar size. The T. reesei PKC1 protein was partially purified and some of its properties examined: it is stimulated about twofold by phospholipids or phorbol esters but is not stimulated by Ca2+. We conclude that these PKC proteins from filamentous fungi represent the Ca(2+)-insensitive fungal homologues of the nPKC family.

Amino Acid Sequence↗
PubMed1996

Identification of some ectomycorrhizal basidiomycetes by PCR amplification of their gpd (glyceraldehyde-3-phosphate dehydrogenase) genes.

Degenerated oligonucleotide primers designed to flank an approximately 1.2-kb fragment of the gene encoding glyceraldehyde-3-phosphate dehydrogenase (gpd) from ascomycetes and basidiomycetes were used to amplify the corresponding gpd fragments from several species of the ectomycorrhizal fungal taxa Boletus, Amanita, and Lactarius. Those from B. edulis, A. muscaria, and L. deterrimus were cloned and sequenced. The respective nucleotide sequences of these gene fragments showed a moderate degree of similarity (72 to 76%) in the protein-encoding regions and only a low degree of similarity in the introns (56 to 66%). Introns, where present, occurred at conserved positions, but the respective positions and numbers of introns in a given taxon varied. The amplified fragment from a given taxon could be distinguished from that of others by both restriction nuclease cleavage analysis and Southern hybridization. A procedure for labeling DNA probes with fluorescein-12-dUTP by PCR was developed. These probes were used in a nonradioactive hybridization assay, with which the gene could be detected in 2 ng of chromosomal DNA of L. deterrimus on slot blots. Taxon-specific amplification was achieved by the design of specific oligonucleotide primers. The application of the gpd gene for the identification of mycorrhizal fungi under field conditions was demonstrated, with Picea abies (spruce) mycorrhizal roots harvested from a northern alpine forest area as well as from a plant-breeding nursery. The interference by inhibitory substances, which sometimes occurred in the DNA extracted from the root-fungus mixture, could be overcome by using very diluted concentrations of template DNA for a first round of PCR amplification followed by a second round with nested oligonucleotide primers. We conclude that gpd can be used to detect ectomycorrhizal fungi during symbiotic interaction.

Base Sequence↗
PubMed1994

Teaching family and community dimensions of clinical family medicine in Venezuela.

BACKGROUND AND OBJECTIVES: In Venezuela, family medicine is taught and practiced almost exclusively in ambulatory care settings. This article describes the evolution of the educational strategies that emphasize family and community aspects of clinical practice within one residency program in the country of Venezuela. METHODS: Three distinct phases of development are depicted, beginning with a biomedical and individual-centered approach. Subsequent efforts to involve residents in the community provoked criticism. Resident-faculty dialogue led to modifications and to the success of the current program. Some of the specific educational strategies are: a structured weekly five-hour community afternoon, a 40-hour course titled "Family Dynamics and Counseling," use of the family-oriented home visit to introduce residents to the community aspects of health care, and completion of a community-based and health-related project. RESULTS: A sample of residents and graduates noted an improved doctor-patient relationship, improved ability to work with groups, and improved skills for incorporating preventive medicine with a community focus into their clinical practice. CONCLUSIONS: The community involvement is enthusiastically supported by the residents, as it is perceived as useful for clinical practice. The program prepares family physicians to become more responsive to the health needs and the reality of Venezuelan society.

Community Health Services↗
PubMed1993

Triggering of cellulase biosynthesis by cellulose in Trichoderma reesei. Involvement of a constitutive, sophorose-inducible, glucose-inhibited beta-diglucoside permease.

We prepared [U-14C]cellobiose by cultivating Acetobacter pasteurianus in the presence of [U-14C]glucose and hydrolyzing the [U-14C]cellulose formed with beta-glucosidase-free cellulase from Trichoderma reesei. This 14C-labeled cellobiose was used to investigate the presence of an uptake system for cellobiose in T. reesei. Evidence was obtained for the presence of a high affinity (Km for cellobiose 0.3 microM) but low activity (2.5 milliunits/mg fungal dry weight) cellobiose permease. The permease is formed constitutively, but higher levels are formed after addition of sophorose (glucosyl-beta-1,2-diglucoside), a reputed cellulase inducer. The permease appears to be specific for beta-diglucosides, as the uptake of [U-14C]cellobiose is inhibited by sophorose, gentiobiose (glucosyl-beta-1,3-glucoside), and cellobiose. Under these conditions, cellooligodextrines (n, 4-7; final concentration, 1 mM) are not inhibitors. Glucose, but no other monosaccharides, inhibits the permease. The hypersecretory mutant T. reesei RUT C-30 exhibits elevated permease activities, whereas in T. reesei QM 9979, a mutant strain defective in the induction of cellulases by cellulose or sophorose, strongly reduced permease activities were demonstrated. The results stress a hitherto not recognized point of control in the induction of cellulases by T. reesei at the level of uptake of cellulose oligosaccharides.

Cellulase↗
PubMed1993

Characterization of the pyruvate kinase-encoding gene (pki1) of Trichoderma reesei.

The pyruvate kinase-encoding gene (pki1) from Trichoderma reesei was isolated by hybridization to the corresponding Aspergillus nidulans pkiA gene. The 1614-bp nucleotide (nt) sequence of the cloned gene codes for a 538-amino-acid protein. The coding sequence contains a single intron of 246 nt at a position identical to that of intron E in the A. nidulans gene. The PKI protein shows extensive homology to the PKIs of A. nidulans and A. niger (67%) and Saccharomyces cerevisiae (59%). The 5' non-coding sequence contains a number of motifs typical for yeast glycolytic genes, but so far only rarely found in filamentous fungi.

Amino Acid Sequence↗
PubMed1993

Characterization of the Trichoderma reesei cbh2 promoter.

A 613-bp fragment of the 5' upstream region of the Trichoderma reesei cbh2 gene (coding for the cellulolytic enzyme cellobiohydrolase II) has been isolated and sequenced. Fusion of this fragment to the E. coli uidA gene (coding for beta-glucuronidase) leads to--albeit low--expression of beta-glucuronidase activity in the presence of cellulose and upon the addition of low molecular weight inducers (sophorose, lactose) of cellobiohydrolase II. It also governed the formation of beta-glucuronidase activity during sporulation and its transport to the conidial surface. However, despite the presence of a signal peptide in the cbh2:uidA fusion, beta-glucuronidase was not secreted in T. reesei. Defined fragments of the 613-bp promoter region were isolated and used to identify areas involved in the regulation of cbh2 expression by protein-DNA binding assays. At least two binding areas--between -443/-363 and -363/-173, respectively--were identified. In both areas, the DNA-protein complex observed was appreciably larger when cell-free extracts from sophorose-induced mycelia were used. This suggests that at least one of the proteins regulating cbh2 transcription is itself induced by cellulose.

Base Sequence↗
PubMed1993

The Trichoderma cellulase regulatory puzzle: from the interior life of a secretory fungus.

Novel applications for cellulases have reinitiated interest in the regulation of production of these enzymes by the soft rot fungus Trichoderma reesei and related species. This paper reviews the current state of knowledge concerning the question "How can insoluble molecules like cellulose initiate their own breakdown by a microorganism?" The evidence available--based on biochemical as well as molecular biological approaches--favors a model in which conidial bound cellobiohydrolases carry out a first exo-exo-wise attack on the cellulose molecule. The disaccharides so formed (cellobiose, alpha-cellobiono-1,5-lactone) are then taken up by the mycelia and promote further cellulase biosynthesis. Evidence available suggests that they are further metabolized to, rather than being, the "true" inducer. Speculations on the nature of the inducer are presented. The roles of the beta-glucosidases of Trichoderma in this process are discussed. The pathway of cellulase secretion is discussed on the basis of electron microscopical as well as gene sequence information.

Amino Acid Sequence↗
PubMed1990

The development of a heterologous transformation system for the cellulolytic fungus Trichoderma reesei based on a pyrG-negative mutant strain.

Six uridine auxotroph mutants of Trichoderma reesei QM 9414 were isolated by resistance to 5-fluoroorotic acid and one strain was identified as OMP-decarboxylase negative (pyr-) by a radiometric enzyme assay. Transformation to uridine prototrophy was achieved with the pyr4 gene of Neurospora crassa (up to 1500 transformants/micrograms) and with pyrA of Aspergillus niger (700-800 transformants/micrograms). In many transformants the PYR+ function seems to be present as extrachromosomal DNA. There is evidence for a correlation between the stability of transformants and integration of the vector in the genome whereas unstable transformants are obtained when autonomous replication of the plasmid occurs.

Blotting, Southern↗