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J Novák

Publications and source records attributed to J Novák.

At least 19 recordsLinked to original sources
PubMed2005

Heterotrophic fixation of CO(2) in soil.

The occurrence of heterotrophic CO(2) fixation by soil microorganisms was tested in several mineral soils differing in pH and two artificial soils (a mixture of silica sand, alfalfa powder, and nutrient medium inoculated with a soil suspension). Soils were incubated at ambient ( approximately 0.05 vol%) and elevated ( approximately 5 vol%) CO(2) concentrations under aerobic conditions for up to 21 days. CO(2) fixation was detected using either a technique for determining the natural abundance of (13)C or by measuring the distribution of labeled (14)C-CO(2) in soil and bacteria. The effects of elevated CO(2) on microbial biomass (direct counts, chloroform fumigation extraction method), composition of microbial community (phospholipid fatty acids), microbial activity (respiration, dehydrogenase activity), and turnover rate were also measured. Heterotrophic CO(2) fixation was proven in all soils under study, being higher in neutral soils. The main portion of the fixed CO(2) (98-99%) was found in extracellular metabolites while only approximately 1% CO(2) was incorporated into microbial cells. High CO(2) concentration always induced an increase in microbial activity, changes in the composition of the microbial community, and a decrease in microbial turnover. The results suggest that heterotrophic CO(2) fixation could be a widespread process in soils.

Bacteria↗
PubMed2005

[Trabeculectomy--long term results].

Goal of this paper was to analyze retrospectively and partially also prospectively the results of trabeculectomies (TE) performed at the Department of Ophthalmology of the University Hospital in Hradec Králové (Königgrätz), Czech Republic, EU, during the 1990-2000 period using the database program GLAUCOM Access 97. The authors did statistical analysis of 538 trabeculectomies performed as the first surgery for lowering the intraocular pressure (IOP) on the followed eye without peroperative use of antimetabolites or cytostatics with follow up period 1-10 years. The baseline criteria for the evaluation were changes of the IOP, visual acuity, and pharmacological treatment after the operation. The average age at the time of the surgery was 61.28 +/- 14.58 years. Surgeries were performed by 11 surgeons. During the follow-up period the IOP lowering effect of the surgery was demonstrated by lowering the average IOP values from 28.42 +/- 8.98 mm Hg to 16.53 +/- 5.93 mm Hg. In the first half of the follow-up period a slight improvement of the visual acuity was noticed, in the second one the visual acuity decreased. Pre-operative average visual acuity was 0.59 +/- 0.34, and at the end of the follow-up period it was 0.59 +/- 0.33. The surgery in glaucoma patients effectively lowered the average number of prescribed antiglaucomatics after TE from 1.92 +/- 0.83 to 0.89 +/- 0.80 drugs. Our evaluations clearly showed trabeculectomy is even in the presence of existence non-perforating surgeries the basic and relatively easy-to-perform IOP lowering technique with broad variety of indications, and with relatively low number of complications.

Female↗
PubMed2005

[Computer program for antiglaucomatous surgeries analysis].

Computer analysis of long-term results of the surgical treatment of glaucoma needs suitable program for database data download retrospectively and prospectively as well. We composed a universal database program Glaucoma Access 97 for patients' follow-up in glaucoma surgery centers. Data about 1073 antiglaucomatous filtering surgeries from the period 1990-2000 were downloaded. The program permits to download data about the patients before the surgery, details about the operation procedure, and from the follow-up visits into the database using special software questionnaire sheets. Outcome from the database may be data about long-term IOP compensation, visual acuity changes, and treatment after the surgery. Evaluation of the data allows to follow up the successfulness of the treatment of specified groups of patients and to compare results of surgeons and individual departments as well.

Databases as Topic↗
PubMed2004

[Duo-Bonharen in a comparative study].

In the 1995-2000 period, data of interest concerning preoperative and postoperative intraocular pressure (IOP) and the best corrected visual acuity (BCVA) in the group of eyes in which the brand name methylcellulose--Adatocel, Ocucoat, Metocel--(n=378) and Viscoat (n=526) was used during the surgery, were statistically evaluated. They were compared to those results obtained from the prospective clinical study performed in 2001-2002 (n=275) by using the new viscoelastic material Duo-Bonharen, which is the Czech product, manufactured on the basis of the hyaluronic acid. All groups were evaluated in a retrospective manner. In the comparative study, statistically significant differences in functional results of cataract surgery in favor of Duo-Bonharen were demonstrated. The cohesive type of the substance used tends to decrease the IOP, the dispersive materials tend to increase the IOP.

Aged↗
PubMed2004

[Early changes of the intraocular tension after the application of Duo-Bonharen Dispersive and Cohesive].

The intraocular pressure (IOP) rise is one of the complications after the application of viscoelastic material during the cataract surgery. The maximum of the elevation occurs between the second and eighth hours after the surgery. Twenty-four hours after the surgery, the IOP decreases to normal values. Because of possible early IOP changes, a group of 52 eyes (39 patients) with Duo-Bonharen Dispersive and Cohesive used, was followed. The IOP was measured at 2, 8, and 24 hours after the surgery. Not a remarkable IOP increase was marked.

Aged↗
PubMed2003

[Duo-Bonharen--a new viscoelastic preparation. Experimental study].

The paper discusses preclinical tests of a new viscoelastic preparation for ophthalmosurgery. Experiments revealed that preparation Duo-Bonharen which contains hyaluronic acid prepared by bacterial fermentation is suited for clinical tests. After a 24-hour interval following administration into the anterior chamber it does not raise intraocular pressure. In experiments it has no side-effects on the eye. The dispersed form in a higher concentration (5%) adheres very well to ocular tissues and protects them adequately during surgery. The cohesive form in an optimal concentration (1.5%) can be rapidly removed from inside the eye. The properties of Duo-Bonharen in experiments are comparable with similar viscomaterials which are used. The new viscoelastic material Duo-Bonharen appears suitable for clinical tests in particular for cataract surgery.

Animals↗
PubMed2002

[IgA nephropathy. Significance of immunoglobulin A glycosylation in pathogenesis and clinical presentation].

Human immunoglobulin A is represented by two structurally and functionally distinct subclasses: IgA1 and IgA2. IgA1, which is almost exclusively present in the mesangial deposits in IgA nephropathy patients, contains in its hinge region three to five O-lined carbohydrate chains. A fraction of IgA1 molecules in the circulation of IgA nephropathy patients exhibits aberrant glycosylation. As a result of changes in glycosylation, the neoepitopes represented by glycans are exposed and recognized by naturally occurring antibodies with antiglycan specifciities, and immune complexes are generated. The deposits of these immune complexes in the glomerular mesangia elicit inflammatory response known as IgA nephropathy. Epidemiological studies have shown that dominant hematuria, either isolated or combined with mild proteinuria, is the most frequent urinary syndrome in glomerulonephritis. The morphologic finding of this syndrome is most frequently IgA nephropathy. Originally considered a benign disease, IgA nephropathy is now recognized as a frequent cause of chronic renal failure. The progression is signalized by increasing proteinuria and hypertension. Therefore, a control of blood pressure and lowering of proteinuria remain the corner-stones of the treatment. Angiotensin converting enzyme inhibitors and AT1 blockers may lower both blood pressure and proteinuria and are now increasingly promoted even for treatment of normotensive patients. Steroids are administered to patients with severe proteinuria. High-doses of fish oil seem to slow down the rate of renal failure.

Glomerulonephritis, IGA↗
PubMed2002

[Adjuvant therapy of renal carcinoma].

A treatment approach in a group of 1498 patients with renal cell carcinoma (RCC) was studied. Out of these, 86 patients had the primarily generalised form. For the therapy of primary advanced metastasis, the treatment strategy was changed from conservative to an active approach. Such approach is based on the removal of 75% of the tumor mass, the patient should be in good conditions with no metastases in CNS, bone and liver, and the primary tumor should not be a sarcoma. The new treatment strategy of patients with advanced RCC combines surgery and chemoimmunotherapy. 47 patients from the studied group were treated with combined INF alpha + IL-2 + 5FU + isotretinoin using the Atzpodien scheme. The toxicity was minimal and only in six patients the treatment was interrupted because of the disease progression. Results of this treatment strategy are encouraging, however, further randomised trials are recommended.

Adult↗
PubMed2002

Qualitative and quantitative detection of urinary human complement factor H-related protein (BTA stat and BTA TRAK) and fragments of cytokeratins 8, 18 (UBC rapid and UBC IRMA) as markers for transitional cell carcinoma of the bladder.

OBJECTIVE: To evaluate the role of BTA stat, BTA TRAK, UBC Rapid, UBC IRMA and voided urinary cytology in the detection of bladder transitional cell carcinoma (TCC). METHODS: The study included 78 patients with TCC of the bladder (group A), 62 patients with a history of bladder TCC without tumor recurrence at the time of examination (B, control group), 20 patients with other malignancy of the urinary tract (C), 38 patients with non-malignant urinary tract diseases (D), 10 patients with urinary tract infection (E) and 10 healthy volunteers (F). Except in group F, voided urine was collected before cystoscopy or cystectomy. RESULTS: The specificity and sensitivity in bladder cancer detection were 87.1 and 74.4%, respectively with BTA stat, 79.3 and 48.7%, respectively with UBC Rapid, 100 and 33.3%, respectively with cytology, 72.6 and 75.6%, respectively with BTA TRAK, 64.5 and 70.5%, respectively with UBC IRMA. CONCLUSIONS: The BTA stat and BTATRAK tests are superior to UBC Rapid, UBC IRMA and urinary cytology in detection of bladder TCC. In daily practice however cytology remains the best adjunct to cystoscopy because of its high sensitivity in Tis and 100% specificity. Cystoscopy cannot be replaced by any of evaluated methods.

Adult↗
PubMed2002

The expression of PAX5, p53 immunohistochemistry and p53 mutation analysis in superficial bladder carcinoma tissue. Correlation with pathological findings and clinical outcome.

OBJECTIVES: The expression pattern of PAX5 in the tissue of superficial bladder transitional cell carcinoma (TCC), its prognostic value and its correlation with p53 immunohistochemistry and p53 mutation analysis were evaluated. METHODS: Study comprised 61 patients with histologically confirmed superficial bladder TCC. Expression level of PAX5 mRNA was investigated using reverse transcriptase-polymerase chain reaction (RT-PCR) and determined semiquantitatively. The presence of p53 mutations was determined by SSCP and confirmed by direct sequencing. The p53 immunohistochemistry was performed with DO1 antibody and semiquantitatively evaluated using HSCORE (HS) method. As the control group for the evaluation of the PAX5 expression served 8 men with benign prostatic hyperplasia. RESULTS: PAX5 expression was found in 50 patients with bladder TCC but in no patient from the control group. Its quantity however correlated neither with the stage nor with the grade of the tumor. P53 mutation was confirmed only in 1 patient with pTaG2 tumor in exon 5 (deletion of proline 128). On the contrary, positive immunohistochemical staining of p53 was detected in most patients. Using the cutoff value of HS 200, 56.9% of patients showed p53 overexpression. Quantity of p53 immunochistochemical positivity did not correlate with the quantity of PAX5 expression. Using the cutoff values of HS 200 for p53 and of 0.2 for PAX5, 7 of 8 patients with future progression had p53 and 4 had PAX5 overexpression respectively. CONCLUSION: The expression of gene PAX5 is a frequent event in superficial TCC of the bladder.

Aged↗
PubMed2002

[Long-term experience with glaucoma silicone implants in a multicenter study].

PURPOSE: To evaluate the experience with a glaucoma implant in complicated glaucoma, designed in collaboration with the Institute of Polymers in Prague. METHODS: In a multicentric retrospective study 91 eyes of 86 patients with otherwise uncontrollable glaucoma underwent GSI implantation in four departments. The implant of medical silicone consists of a tube with an internal diameter of 0.4 mm, connected to a round lens-shaped episcleral plate 169 mm2, covering the tube orifice from above. The indications were infantile glaucoma (14 eyes), traumatic glaucoma (14 eyes), various secondary glaucomas in 12, primary open-angle glaucoma in 11, neovascular and after PPV in 10 eyes each, usually after unsuccessful previous surgery. RESULTS: The average follow-up time was 20.5 months (SD +/- 19.5). Postoperative intraocular pressure at the last control was 6-22 mmHg in 56 eyes (50.95%). Life table analysis showed a cumulative probability of 494% (at least qualified success). Long-term hypotony was seen in 6 eyes. CONCLUSIONS: The GSI is comparable with similar tube shunts but is much less expensive. In vitro experiments are planned to improve the construction of the implant and its results.

Adolescent↗
PubMed2002

[Metastatic involvement of the iris in primary carcinoma of the lung].

The authors describe a quite unique case of metastatic affection of the iridial tissue in a 69-year-old female patient treated from 2000 for primary lung cancer. Before assessment of the ophthalmological diagnosis the patient reported pain and redness of the right eye persisting for two weeks. On examination extensive proliferating tissue in the area of the temporal part of the right iris was found and secondarily a painful glaucoma. Treatment with regard to the case-history and general condition of the patient involved enucleation of the affected eye. Histological examination confirmed subsequently the presence of a metastasis of a small cell spindle-shaped lung cancer into the iris with dissemination in the anterior chamber and corneal endothelium.

Aged↗
PubMed2001

[Schoenlein-Henoch purpura in adulthood (gastrointestinal manifestation and endoscopy)].

During a 15-year-period 62 adult patients were admitted with diagnosis of Schoenlein-Henoch purpura in our hospital. 25 female and 37 male patients ranged from 30-87 years (mean: 59.5 years) presenting with cutaneous, joint, renal and particularly abdominal involvement were investigated retrospectively. During the course of the disease, all patients developed purpuric rash (100 %), 14 (22,5 %) patients had joint symptoms and renal involvement occurred in 12 (19,3 %) patients. In this study, we discuss 15 (24 %) patients with gastrointestinal symptoms appearing in Henoch's purpura. Analysis of the gastrointestinal clinical features revealed: Abdominal pain 13 (86 %), massive colorectal bleeding 3 (20 %), occult blood loss 10 (66 %) vomiting 6 (40 %) and diarrhea in 3 (20 %) patients. Surgical consultation was obtained for 4 of the 15 patients and laparotomy was performed in 2 patients. All the patients underwent lower and upper endoscopic examination, in 3 cases the authors saw purpuric mucosal lesions in duodenum and in 8 patients were also found coin-like elevated lesions, additionally, biopsy from colonic lesions showed leukocytoclastic vasculitis. It is concluded that endoscopy may play a very important role in the diagnosis and treatment of Schoenlein-Henoch purpura.

Adult↗
PubMed2001

[Changes in the quality of life after cataract surgery].

The questionnaire VF-14 is one of the most frequently used methods for exploration of patients' subjective evaluation of cataract surgery outcomes. In this study, the answers of 349 patients' were evaluated. These respondents completed the questionnaires before cataract surgery and again after 6 months. When the postoperative questionnaires were filled-in, 196 respondents had one eye operated on (group A), and 153 had both eyes operated on (group B). All cataract surgeries were performed by phacoemulsification. The complication--rupture of the posterior capsula--occured in 0.8%. In 26.7% patients an accompanying secondary eye disease was found. The average VF-14 index was 63.5 (SD 21.32) in group A and 59.4 (SD 22.62) in group B. After the surgery the VF-14 index increased significantly--in group A was the average 80.6 (SD 20.47) and in group B even higher 87.2 (SD 16.14). The change of VF-14 index prior to and after the operation was proven to be statistically significant both in group A and in group B (p < 0.001). The improvement of the VF-14 index was found in group A in 80.6% and in group B in 88.9% of respondents. The patients' satisfaction with their vision after cataract surgery was highly increased. The outcomes of the questionnaire study document the high success rate of cataract surgery for patients.

Aged↗
PubMed2000

Biotransformation of styrene in mice. Stereochemical aspects.

Biotransformation of styrene and its toxic metabolite, phenyloxirane (1), in mice in vivo was studied. Mice were treated with single intraperitoneal doses of styrene (400 mg/kg of body weight), and with (R)-, (S)-, or racemic styrene oxide (150 mg/kg of body weight). Profiles of neutral and acidic metabolites were determined by GC/MS. Mandelic acid (3) and two mercapturic acids, N-acetyl-S-(2-hydroxy-2-phenylethyl)cysteine (5) and N-acetyl-S-(2-hydroxy-1-phenylethyl)cysteine (6), were found to be major urinary metabolites of both styrene and phenyloxirane. 1-Phenylethane-1,2-diol (2) was the main neutral metabolite. The rate of excretion of this metabolite, as determined by GC, was 5-10 times lower than that of mandelic acid. Several minor acidic metabolites were also identified. Among them, novel phenolic metabolites, namely, 2-(4-hydroxyphenyl)ethanol (7), (4-hydroxyphenyl)acetic acid (11), and two isomeric hydroxymandelic acids (12), are of toxicological significance. Main stereogenic metabolites were isolated as methyl esters from extracts of pooled acidified urine treated with diazomethane. The mandelic acid that was obtained was converted to diastereomeric Mosher's derivatives prior to analysis by NMR. Mercapturic acids were analyzed directly by (13)C NMR. Pure enantiomers of 1 were metabolized predominantly but not exclusively to corresponding enantiomers of 3. Styrene yielded predominantly (S)-mandelic acid. Fractions of mercapturic acids 5 and 6 isolated from urine amounted to 12-15% of the dose for all compounds that were administered. Conversion to mercapturic acids was highly regio- and stereoselective, yielding predominantly regioisomer 5. Styrene, as compared to racemic phenyloxirane, yielded slightly more diastereomers arising from (S)-1 than from (R)-1. These data can be explained by formation of a moderate excess of the less mutagenic (S)-1 in the metabolic activation of styrene in mice in vivo.

Acetylcysteine↗
PubMed2000

Covalent structure of mutacin 1140 and a novel method for the rapid identification of lantibiotics.

The primary structure of the Streptococcus mutans lantibiotic mutacin 1140 was elucidated by NMR spectroscopy, mass spectrometry, and chemical sequencing. The structure is in agreement with other closely related lantibiotics, such as epidermin. A novel method was developed in which mutacin 1140 was chemically modified with sodium borohydride followed by ethanethiol, allowing the differentiation of the thioether-containing residues from the dehydrated residues. This double-labeling strategy provides a simple method to reliably identify all modified lantibiotic residues with a minimal amount of material. While NMR spectroscopy is still required to obtain thioether bridging patterns and thus the complete covalent structure, the double-labeling technique, along with mass spectrometry, provides most of the information in a fraction of the time required for a complete NMR analysis. Thus, with these new techniques lantibiotics can be rapidly characterized.

Amino Acid Sequence↗