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J Marin

Publications and source records attributed to J Marin.

At least 19 recordsLinked to original sources
PubMed2006

Distribution of Epstein-Barr virus genotypes in throat washings, sera, peripheral blood lymphocytes and in EBV positive tumor biopsies from Slovenian patients with nasopharyngeal carcinoma.

Nasopharyngeal carcinoma (NPC) is a malignancy closely associated with Epstein-Barr virus (EBV). It is prevalent among the Chinese of Southern China, whereas outside China, the position seems to be different. The aim of this study was to determine the distribution of EBV genotypes in the patients with NPC in Slovenia, which is a nonendemic area. Detection of EBV was undertaken by testing the throat washes, sera, peripheral blood lymphocytes (PBLs), and biopsies of primary tumors of 48 patients with NPC in Slovenia. The sera of 20 patients with serologically confirmed primary EBV infection served as a control clinical material. The analysis of genotypes was carried out on three regions of EBV genome; BamHI WYH, BamHI I, and BamHI F, using the polymerase chain reaction (PCR) and restriction fragment length polymorphism (RFLP). The results show that, in Slovenia, the predominant combination of EBV genotypes based on the differences in the three genomic regions is ADF. This combination was found in 56 out of 103 different EBV positive clinical samples (throat washes, sera, PBLs, and tumor biopsies) of patients with NPC and in 15 out of 17 sera of patients with primary EBV infection. Very low number of genotypes C and f were detected, in spite of the fact that these two genotypes were considered to be associated with the development and/or maintenance of NPC in Southern China. Genotype f was found in only two tumor biopsies; in all other clinical samples (throat washes, sera and PBLs), genotype F was detected. Genotype C was proven in 31/103 clinical samples, with the highest percentage in tumor biopsies (37.5%). As in the NPC patients from other countries (Alaska is an exception), genotype A was predominant and was detected in 86/103 clinical samples. Genotype B was found in 15 clinical samples of patients with NPC and in 3 the two genotypes A and B were found. In comparison to China, these results show different EBV genotypes distribution. It seems that the genetic disposition of human population is an important factor that may contribute to different susceptibility for specific EBV genotypes.

Adolescent↗
PubMed2006

Zosteriform lichen planus-like eruption.

Lichen planus (LP) is a relatively common papulosquamous skin disease of unknown etiology, it is believed to be a T-cell mediated disorder. In addition to the cutaneous eruptions it may also affect mucous membranes, nails or cause scarring alopecia. Lichen planus appears in various clinical variants which are categorized according to the morphology and configuration of lesions. We present a 34-year-old man who developed a papular eruption localized unilaterally on the right side of the body in a linear-zosteriform pattern within the L5-S1 nerve segments. The skin lesions clinically and histologically mimicked LP. Topical treatment with betamethason ointment for one month led to remarkable improvement, but a zosteriform hiperpigmentation persisted. According to the clinical findings in our patient and a review of the literature, we believe that lichenoidzosteriform eruption is a variant of lichen planus or a herpes zoster infection.

Adult↗
PubMed2005

The emergence of rotavirus genotype G9 in hospitalised children in Slovenia.

BACKGROUND: Rotavirus G9 genotype was thought to be the fifth most common genotype circulating amongst the population. In previous studies in Slovenia, only G1, G3 and G4 genotypes were detected. OBJECTIVES: To determine G and P genotypes of rotaviruses causing dehydrating gastroenteritis in children hospitalised at the University Medical Centre Ljubljana during the winter season 2001-2002. Some data obtained in previous years are included, too. STUDY DESIGN: For the G and P genotypes determination, we selected 99 of the total of 565 rotavirus positive samples. RT-PCR was carried out for G gene or partial P gene amplification. The RT-PCR product was used as a template for multiplex nested PCR using genotype-specific primers. In untypable samples, a sequence analysis of a short segment of G or P gene was performed. From the period before July 2001, 183 stool samples were examined using the same methods. RESULTS: Genotype G1 was determined in 37, G4 in 6, and G9 in 28 samples out of 99. Only one sample showed a mixed infection with G1G4 genotype specifics. Following the sequence analysis of the short segment of G gene in 11 G9 genotypes, 2 different clusters of G9 genotype were determined. All samples had the same P genotype--P[8]. G9 genotype had not been detected prior to July 2001. CONCLUSION: Rotavirus G9 genotype emerged in Slovenia in the year 2001. Two different clusters were determined which have to be further characterised in detail.

Child↗
PubMed2005

Prevalence of some herpesviruses in gingival crevicular fluid.

BACKGROUND: The herpesviruses, ancient pathogens which have co-evoluted with human, are etiologically associated with a number of diseases, from asymptomatic to oncogenic and mortal diseases. It seems that some of them have also an important role in the pathogenesis of human periodontal disease. OBJECTIVE: This study aimed to determine the prevalence of Epstein-Barr virus (EBV), human herpesvirus 6 (HHV-6), human herpesvirus 8 (HHV-8) and human cytomegalovirus (HCMV) in gingival crevicular fluid (GCF) and, eventually, to find the correlation between specific virus types and clinical parameters which are important in periodontitis, like plaque index (PI), gingival index (GI) and probing depth (PD). STUDY DESIGN: A polymerase chain reaction (PCR) and digestion of PCR products with restriction endonuclease were employed to identify the presence of EBV, HHV-6, HHV-8 and HCMV. RESULTS: Out of 66 samples of GCF taken from the patients with periodontal disease, EBV was found in 29 (43.9%), HHV-6 in 16 (24.2%) and HCMV in 2 (3%) samples, while in the samples of healthy persons, these viruses were not found. HHV-8 was detected neither in the patients with periodontitis nor in healthy control group. More positive results were found in clinical samples taken from people with higher PI and GI and in the samples taken from the patients with medium PD (PD=3-6mm). In all HHV-6 positive samples, we found only variant A; as for EBV positive samples, type A and type B were identified and also co-infection with the two types. It seems that there is a correlation between PI, PD and EBV types, but no correlation was found between EBV types and GI or HHV-6 types and PI, PD, GI. CONCLUSIONS: The present findings confirm some association between herpesviruses and human periodontitis.

Adult↗
PubMed2004

Synthesis of enantiopure 4-hydroxypipecolate and 4-hydroxylysine derivatives from a common 4,6-dioxopiperidinecarboxylate precursor.

tert-Butyl 2-substituted 4,6-dioxo-1-piperidinecarboxylates 4 have been prepared in good yield starting from Boc-Asp-O(t)Bu and other beta-amino acids. By analogy with chiral tetramic acids, their reduction by NaBH(4) in CH(2)Cl(2)/AcOH afforded the corresponding cis-4-hydroxy delta-lactams in good yield and stereoselectivity (68-98% de). In the absence of the A(1,3) strain (reduction of 6-substituted 2,4-dioxo-1-piperidines 7), the cis-4-hydroxy isomer was still obtained as the major product but the de values were consistently lower. 4-Hydroxy-6-oxo-1,2-piperidinedicarboxylate 2a, readily accessible from Boc-Asp-O(t)Bu (three steps, 63% overall yield), has proven to be an excellent building block for the synthesis of cis- and trans-4-hydroxypipecolates 17 and 24 (52 and 36% overall yield, respectively) and for the synthesis of a protected 4-hydroxylysine derivative 29 (41% overall yield).

Chromatography, High Pressure Liquid↗
PubMed2004

Autologous stem-cell transplantation in diffuse large B-cell non-Hodgkin's lymphoma not achieving complete response after induction chemotherapy: the GEL/TAMO experience.

BACKGROUND: Here we evaluate the results of high-dose chemotherapy and autologous stem-cell transplantation (HDC/ASCT) in 114 patients included in the GEL/TAMO registry between January 1990 and December 1999 with diffuse large B-cell lymphoma who failed to achieve complete remission (CR) with front-line conventional chemotherapy. PATIENTS AND METHODS: Sixty-eight per cent had a partial response (PR) and 32% failed to respond to front-line therapy. At transplant, 35% were chemoresistant and 29% had two to three adjusted International Prognostic Index (a-IPI) risk factors. RESULTS: After HDC/ASCT, 57 (54%) of 105 patients evaluable for response achieved a CR, 16 (15%) a PR and 32 (30%) failed. Nine patients were not assessed for response because of early death due to toxicity. With a median follow-up of 29 months for alive patients, the survival at 5 years is 43%, with a disease-free survival for complete responders of 63%. The lethal toxicity was 8%. Multivariate analysis revealed a-IPI and chemoresistance to be predicting factors. CONCLUSIONS: Our results show that one-third of patients who do not obtain a CR to front-line chemotherapy may be cured of their disease with HDC/ASCT. However, most chemoresistant patients pretransplant failed this therapy. For this population, as well as for those who presented with adverse factors of the a-IPI, pretransplant novel therapeutic modalities need to be tested.

Adolescent↗
PubMed2003

Removal of some heavy metal cations from aqueous solutions by spruce sawdust. II. Adsorption-desorption through column experiments.

The adsorption-desorption of copper ions and a mixture of five metal ions (cadmium, copper, nickel, lead and zinc) in aqueous solutions by a spruce sawdust column was reported. Different studies about the copper binding mechanism, the efficiency of some regenerating solutions for the copper desorption, the use of column for copper adsorption-desorption by successive cycles as well as the adsorption-desorption of a multi-component solution were investigated. An ion exchange mechanism seemed to explain the removal of copper by the natural components of sawdust, i.e., calcium, magnesium and manganese accounting for 71, 13 and 5.5% respectively of the copper binding on sawdust. But there was evidence variation in the contribution of these ions during the copper adsorption in the continuous flow process. Regeneration ofthe sawdust column was described by the efficiency sequence: H+ > Ca2+ >> Na+, where protons were the most promising regenerating agents. Adsorption-desorption cycles showed that copper binding capacity of sawdust, after a decrease of 23% between cycles 1 and 2, was stabilized at 3.1 x 10(-2) meq g(-1) for the following cycles. Adsorption of a mixture of five metal ions indicated that nickel broke through first when saturation of sawdust was reached, followed by the other metal ions in the order zinc, cadmium, copper and lead. The effects of competitive ion exchange, because of affinity differences between the metal ions for sawdust, resulting in the metals having the lower affinity being displaced by those having a higher one and to overshoot the 0.2 meq l(-1) feed solution.

Adsorption↗
PubMed2002

Diastereoselective hydroxylation of 6-substituted piperidin-2-ones. An efficient synthesis of (2S,5R)-5-hydroxylysine and related alpha-amino acids.

The synthesis of (2S,5R)-5-hydroxy-6-oxo-1,2-piperidinedicarboxylates (5) and related (3S,6R)-3-hydroxy-6-alkyl-2-oxo-1-piperidinecarboxylates has been developed. The approach is based on the asymmetric hydroxylation of enolates generated from the corresponding N-protected-6-substituted piperidin-2-ones. The utility of 5a as a precursor in the synthesis of (2S,5R)-5-hydroxylysine (1), an amino acid unique to collagen and collagen-like proteins, has also been demonstrated. (2S)-6-oxo-1,2-piperidinedicarboxylates (6) required for hydroxylation studies were prepared in 38-74% yield, starting from conveniently protected aspartic acid as inexpensive chiral adduct. Hydroxylation of 6 to 5 proceeds in high yield and excellent diastereoselectivity by treatment of their Li-enolate with (+)-camphorsulfonyloxaziridine at -78 degrees C. Ring opening of di-tert-butyl (2S,5R)-6-oxo-1,2-piperidinedicarboxylate ((5R)-5a) under reductive conditions afforded the corresponding 1,2-diol (17) in 91%, which was further transformed to (2S,5R)-5-hydroxylysine in four steps (84%). 17 is also a versatile intermediate in the preparation of tert-butyl (2S,5R)-2-[(tert-butoxycarbonyl)amino]-5-hydroxy-6-iodohexanoate (3) and tert-butyl (2S)-2-[(tert-butoxycarbonyl)amino]-4-[(2R)-oxiranyl]butanoate (4), two amino acid derivatives used in the total synthesis of the bone collagen cross-link (+)-pyridinoline (2a).

Amino Acids↗
PubMed2002

Removal of some heavy metal cations from aqueous solutions by spruce sawdust. I. Study of the binding mechanism through batch experiments.

The biosorption of five metal ions, cadmium, copper, nickel, lead and zinc in single component solutions and a multicomponent mixture in aqueous solutions by spruce sawdust is reported. A comparative study, performed through batch experiments, between the cationic release of sawdust in ultra pure water and in a metallic solution leads to an understanding of the heavy metal ion fixation mechanism on sawdust. An empirical model is developed in order to distinguish between a sorption phenomenon purely based on ion exchange from one in which physical adsorption is involved. Thus, the difference in cations released between the two solutions corresponds to the metal ions which bind to anionic sites by displacing protons from acidic groups and existing cations (natural components of the sawdust) from anionic sites. Metal ion binding capacities of spruce sawdust reach values ranging from 2.1 to 4.3x10(-2) meq g(-1) in single metal ion solutions with the following relative preference: Zn < Ni < Cd << Cu < Pb. Our results show variable contributions of the different cations of the sawdust in the ion exchange mechanism in which calcium, naturally present in the sawdust, accounts for about 65% of the biosorption of the metal ions studied. The study also indicates the possibility of desorbing the loaded metal ions with a calcium solution.

Adsorption↗
PubMed2000

Fees for outpatient operations in Germany: development, evaluation and European comparison.

In Germany, discussions on the fees for statutory sickness insurance for ambulatory surgery has, in the last few years, become almost a symbol of dispute for the German health services. Outpatient surgeons complain about the fact that the fees do not cover their services. They see innovation severely threatened by bureaucracy, profitability by planned economy, rights by reasons of State, aggravated by the 'reform' attempts of the Greens and Socialist coalition Federal Government. On the other hand their opponents complain about the money mindedness of the doctors. Intentional panic or real disaster? The fundamental consideration to clarify this question is based on a comparison of the German statutory medical insurance fees and private fees with our neighbours. In Europe an economic area with similar prices for goods, services and wages, even 'outpatient operations' services with comparable cost rates should be paid for at a corresponding level. Any discrepancies would give cause to look for an explanation by analysing the historic development of fees and the question of a fair comparison between operations and the non-operative services.

Journal Article↗
PubMed2000

Persistence of viruses in upper respiratory tract of children with asthma.

OBJECTIVES: Nasopharyngeal swabs of 50 asthmatic children in the symptom-free period were examined for the presence of adenoviruses, rhinoviruses and coronaviruses. A control group of 20 healthy individuals was included in this study. METHODS: A polymerase chain reaction was used to detect adenovirus DNA and rhinovirus and coronavirus complementary DNA. The fragments of amplified genetic material were visualized with the use of agarose gel electrophoresis. RESULTS: Adenovirus DNA was found in 78.4% of asthmatic children, rhinovirus RNA in 32.4% and coronavirus RNA in 2.7%. Adenovirus DNA was detected in one of the 20 nasopharyngeal swabs of healthy controls; the rest of the control samples were negative. CONCLUSIONS: The persistent presence of viruses in the upper respiratory tract of asthmatic children shows a possible connection between viral infections and asthma.

Adenoviridae↗
PubMed2000

Oxidative stress induced by tert-butyl hydroperoxide causes vasoconstriction in the aorta from hypertensive and aged rats: role of cyclooxygenase-2 isoform.

We analyzed the mechanisms involved in the effect of tert-butyl hydroperoxide (t-BOOH) in isolated aortic rings with and without endothelium from normotensive Wistar-Kyoto rats (WKY) and spontaneously hypertensive rats (SHR) at 6, 18, and 24 months of age. t-BOOH (1 microM-10 mM) induced concentration-dependent contractions that were scarcely modified by aging and potentiated in SHR and by endothelium removal. The nitric oxide synthase and prostacyclin synthase inhibitors N(G)-nitro-L-arginine methyl ester (100 microM) and tranylcypromine (100 microM), respectively, increased both basal tone and the t-BOOH-induced contractions in intact segments from WKY, with these effects not observed in SHR. Indomethacin (10 microM), a nonspecific cyclooxygenase inhibitor, and SQ 29,548 (10 microM), a prostaglandin H(2)/thromboxane A(2) receptor blocker, abolished the t-BOOH-induced vasoconstriction, independent of age and hypertension. In both strains, these contractile responses were unaltered by the thromboxane synthase inhibitor imidazole (10 microM). The cyclooxygenase-2 inhibitor NS-398 (10 microM) abolished or markedly reduced the t-BOOH-induced contractions in segments with or without endothelium, respectively. In addition, expression of cyclooxygenase-2 protein was detected in aorta from WKY and SHR in either basal condition or after stimulation with t-BOOH. These results suggest that (1) t-BOOH-induced vasoconstriction in the aorta from WKY and SHR is essentially mediated by cyclooxygenase-2 metabolites, different from thromboxane-A(2), probably prostaglandin-H(2), and/or isoprostanes; (2) aging scarcely modifies, whereas endothelium negatively modulates, these contractions in both strains; and (3) nitric oxide and prostacyclin exert a negative modulator role on the t-BOOH-induced vasoconstriction in WKY, with this modulator role lost in SHR.

Aging↗
PubMed1999

Free radical scavengers to prevent reperfusion injury following experimental warm liver ischaemia. Is there a real physiological benefit?

Free radical scavengers have been utilized to prevent the consequences of ischemia, however, results do not seem conclusive. In our study we analyzed the blood flow, function, and histology of rat liver tissue after warm liver ischemia, in order to assess the effect of free radicals in liver reperfusion injury. N-acetyl cysteine (NAC), tocopherol, allopurinol, and superoxide dismutase (SOD), pharmacological agents expected to protect from injury mediated by free radicals, were investigated. Laser Doppler flowmetry and photometry were utilized to measure post-ischemic microcirculatory changes as an expression of ischemia-reperfusion injury in a model of segmental liver ischemia in the rat, with an ischemic time of 45 min. Galactose elimination capacity, ALT and histology were used to assess the functional and morphological consequences of ischemia after 24 h of reperfusion. The overall mean blood flow over 1 hour after reperfusion was of 33.9% (SD 11.2) of the normal, non-ischemic control. NAC (31.2% SD 10.9) did not show any protective effect and in some cases the effect seemed to be negative. Tocopherol (41.7% SD 5.1) marginally improved post ischemic liver tissue blood flow. Treatment with allopurinol did not show any beneficial effects (37.5% SD 14.2). Only animals treated with SOD showed an improvement of the post ischemic liver microcirculation (57.9% SD 14.4)(P < 0.001) and function. Only SOD produced statistically significant differences in galactose elimination capacity, compared with those of the ischemic control group. This moderately protective effect of SOD is encouraging, however, the relevance of all these compounds in a broader pathophysiological setting remains unproven.

Acetylcysteine↗
PubMed1999

Binding capacity of various fibre to pesticide residues under simulated gastrointestinal conditions.

The purpose of this study was to compare the effect of the nature and quantity of various dietary fibre (cellulose, hemicellulose, pectin, lignin) in diets on the binding capacity to pesticides azinphos-methyl (AZM), chlorpropham (CLP), chlorothalonil (CKL), permethrin (PER) as estimated by solubility under conditions of pH and temperature simulating those in the gastrointestinal tract (incubated at pH 2 for 30 min at 37 degrees C, then at pH 7 for 60 min). The ratios of fibre to pesticides were determined in omnivorous diets. In this model, the binding capacity of lignin was equal to hemicellulose for PER, AZM and CLP, but it was significantly higher for CKL. Hemicellulose bound more CKL, AZM and CLP than did cellulose. Although pectin appreciably decreased all pesticides, its effect was lower than other fibres with one exception--cellulose-CKL. In the presence of equal amounts of fibre, lignin exerted the most significant effect on pesticide solubility. Hemicellulose and cellulose bind to the same extent PER and AZM. The effect of pectin was significant only on CKL and AZM when compared to the control.

Adult↗
PubMed1998

Human papillomavirus 16 and 18 infection of the uterine cervix in women with different grades of cervical intraepithelial neoplasia (CIN).

OBJECTIVE: To evaluate the frequency of human papillomavirus (HPV) 16 and 18 infection in patients with different grades of cervical intraepithelial neoplasia (CIN). METHOD: Five-hundred and five patients with CIN, referred for conization, were included in this study. Before conization, cytological material for in situ hybridization was obtained from the uterine cervix to detect the presence of HPV 16 and 18 infection. RESULT: Among all patients with CIN, 82 (16.2%) were solely HPV 16 and 51 (10.1%) were solely HPV 18 positive. There were 133 patients (26.3%) positive for HPV 16 or HPV 18 and 31 patients (6.1%) were positive for both viral types, giving an overall HPV 16/18 infection rate of 32.4%. There were 15 (55.5%) HPV 16 or HPV 18 positive patients with CIN 1, 45 (33.8%) HPV 16 or HPV 18 positive patients with CIN 2 and 104 (30.2%) HPV 16 or HPV 18 positive patients with CIN 3. CONCLUSION: In patients with CIN 1, HPV 16 and 18 infection was more frequent than in patients with CIN 2, but the difference was not significant. Patients with CIN 2 were infected slightly more frequently, but not significantly, than patients with CIN 3. On the other hand, patients with CIN 1 were significantly more frequently infected than patients with CIN 3.

Adult↗