Heterogeneity of the hemoglobin of the Ohrid trout (Salmo L. typicus)

We have analyzed the hemoglobins of five individual trout from the Ohrid Lake (Salmo L. typicus) by electrophoretic methods, by reversed-phase high-performance liquid chromatography, and by limited structural analyses. The two major classes of hemoglobin are type I (35% of total) and type IV (65%). Type IV is the major oxygen-transporting hemoglobin; it consists of three types of chain (in about equal quantities) and three types of chain (one major and two minor types). Several structural differences have been observed between these three (IV) chains and between the three (IV) chains, suggesting a complex genetic system governing the synthesis of these proteins. Moreover, a few amino acid substitutions occur at positions involved in contacts between chains, which suggests that differences in oxygen affinity may exist between these various type IV hemoglobins. Type I hemoglobin is less complex because it contains one type of chain and two chains; the latter two differ in numerous positions, suggesting duplications of the (I)-globin gene. The and chains of type I hemoglobin differ considerably from the and chains of type IV hemoglobin, indicating the existence of (I)- and (I)-globin genes separate from the (IV)- and (IV)- globin genes.This study was supported in part by the Yugoslav-American Joint Funds, pp 812 (to G.D.E.), and by United States Public Health Service Research Grant HLB-05168 (to T.H.J.H.).     

Increased rectal microbial richness is associated with the presence of colorectal adenomas in humans

Differences in the composition of the gut microbial community have been associated withdiseases such as obesity, Crohn''s disease, ulcerative colitis and colorectal cancer(CRC). We used 454 titanium pyrosequencing of the V1–V2 region of the 16S rRNA geneto characterize adherent bacterial communities in mucosal biopsy samples from 33 subjectswith adenomas and 38 subjects without adenomas (controls). Biopsy samples from subjectswith adenomas had greater numbers of bacteria from 87 taxa than controls; only 5 taxa weremore abundant in control samples. The magnitude of the differences in the distal gutmicrobiota between patients with adenomas and controls was more pronounced than that ofany other clinical parameters including obesity, diet or family history of CRC. Thissuggests that sequence analysis of the microbiota could be used to identify patients atrisk for developing adenomas.     

Interobserver variability in cytologic subclassification of squamous intraepithelial lesions--the Bethesda System vs. World Health Organization classification

The aim of the study was to compare interobserver variability for The Bethesda System (TBS) and World Health Organization (WHO) classification of cervical squamous intraepithelial lesions. A total of 1,000 conventional Papanicolaou smears (156 positive and 884 negative) were examined "blindly" by three cytologists and one cytotechnician. The degree of observer agreement was expressed by kappa statistics using a program for the calculation of interobserver variation and association "Agree" (Svanholm and Jergensen, 1989). Kappa (kappa) was determined for each cytologic diagnosis within a particular classification and total for either classification. The association with and separation from other diagnoses was determined for each cytologic diagnosis in the form of conditional probability (P(j)). In WHO classification, the diagnoses of dysplasia media and dysplasia gravis showed poor reproducibility (kappa = 0.114 and kappa = 0.259, respectively), the diagnosis of dysplasia levis good reproducibility (kappa = 0.639), and the diagnosis of carcinoma in situ excellent reproducibility (kappa = 0.762). WHO classification yielded pool kappa of 0.741. In TBS classification, the diagnosis of LSIL showed good, and HSIL excellent reproducibility (kappa = 0.542 and kappa = 0.763, respectively). TBS classification yielded pool kappa of 0.699. Dysplasia media (P(j) = 0.121) and dysplasia gravis (P(j) = 0.274) were found to be morphologically poorly defined, and carcinoma in situ (P(j) = 0.777) and dysplasia levis (P(j) = 0.651) well defined diagnoses. LSIL was morphologically moderately defined (P(j) = 0.587) and HSIL well defined (P(j) = 0.789) diagnosis. Accordingly, TBS does not substantially improve diagnostic reproducibility of the cytologic diagnoses of squamous intraepithelial lesions, while providing considerably less information to the clinician than the four-grade dysplasia/CIS terminology, thus eliminating the opportunity of choosing a different procedure for the diagnosis of dysplasia media, which is of utmost importance in the population of young nulliparae.     

Sorption properties of TEMPO-oxidized natural and man-made cellulose fibers

Cotton and lyocell fibers were oxidized with sodium hypochlorite and catalytic amount of sodium bromide and 2,2,6,6-tetramethylpiperidine-1-oxy radical (TEMPO), under various conditions. Water-insoluble fractions, collected after TEMPO-mediated oxidation, were analyzed and characterized in terms of weight loss, aldehyde and carboxyl contents, and sorption properties. Aldehyde and carboxyl groups were introduced into the oxidized cotton up to 0.321 and 0.795 mmol/g, and into the oxidized lyocell up to 0.634 and 0.7 mmol/g, respectively, where weight loss was generally lower than 12% for cotton and 27% for lyocell. Oxidized cotton and lyocell were shown to exhibit 1.55 and 2.28 times higher moisture sorption than the original fibers, respectively, and water retention values up to about 85% for cotton and 335% for lyocell, while iodine sorption values of oxidized fibers were lower up to 35% for cotton and up to 18% for lyocell than the original fibers.     

Exercise-induced changes in redox status of elite karate athletes

Regular training has been claimed to increase the activity of antioxidant enzymes and, consequently, augments the resistance to oxidative stress; however, large volumes of training performed by elite sportsmen could lead to a chronic oxidative stress state. The aim of our study was to assess the oxidative status of elite athletes at the beginning of the preparatory and the beginning of the competition training phases, so that the influence of three months of programmed physical activity on redox status could be determined. The chronic effects of exercise on the redox state of the athletes were compared to the effects of a single bout of karate training. Thirty elite karate athletes, 16-30 years old, were subjected to maximal graded exercise test to estimate their aerobic capacity; blood sampling was also performed to measure levels of superoxide anion radical (O??), hydrogen peroxide (H?O?), superoxide dismutase activity (SOD) and catalase activity (CAT). The only significant change after the three-month training process was found in the significantly decreased CAT activity (X ± SE: 7.95 ± 0.13 U/g Hb × 103 in the preparatory period, 6.65 ± 0.28 U/g Hb × 103 in the competition stage; P < 0.01). After a single karate training session, there was statistically significant decrease of O??(X ± SE: 32.7 ± 4.9 nmol/ml in the preparatory period, 24.5 ± 2.5 nmol/ml in the competition stage; P < 0.05) and increase of H?O?(X ± SE: 11.8 ± 1.0 nmol/ml in the preparatory period, 14.2 ± 0.9 nmol/ml in the competition stage; P < 0.01), as well as significant CAT increase (X ± SE: 6.6 ± 0.6 U/g Hb × 103 in the preparatory period, 8.5 ± 0.5 U/g Hb × 103 in the competition stage; P < 0.05). Although the three-month training process induced, at the first sight, negative changes in the redox state, expressed through the decrease in CAT activity, adequate response of the antioxidant system of our athletes to acute exercise was preserved.     

Variability in chemical composition and abundance of the rare tertiary relict Pinus heldreichii in Serbia

The particular significance of the whitebark pine (Pinus heldreichii Christ.) stems from the fact that it is a tertiary relict and Balkanic subendemite covering a very narrow and intermittent area in Serbia. A representative pool of 48 adult trees originating from three populations, one recently discovered natural (Population I) and two planted populations (Populations II and III) was investigated in order to evaluate the intra- and interpopulation variability of the essential oil of the complete fund of P. heldreichii in Serbia. In the pine-needle-terpene profile, 104 compounds were detected, 84 of which could be identified. Among the essential-oil constituents, monoterpenes and sesquiterpenes dominated, comprising ca. 90% of the essential oil. The terpenic profile of Population I was characterized by a predominance of monoterpenes (e.g., limonene (1), α-pinene, and Δ(3) -carene (4)), while sesquiterpenes (e.g., germacrene D (2) and β-caryophyllene (3)) obviously preponderated in the profile of Populations II and III. This study also demonstrated that the abundance of whitebark pines in Serbia had significantly changed over the last few decades. The number of individuals in the natural population had increased, while the number of individuals in the planted populations had decreased. Today, the whitebark pine fund in Serbia comprises less than 250 trees.     

Poly(A) tailing of ancient DNA: a method for reproducible microsatellite genotyping

Microsatellites could be of great potential use in the analysis of ancient remains, but so far such analyses have failed to be reproducible mainly because of the high degree of ancient DNA (aDNA) degradation. During PCR, annealing of the primers to the complementary sequences of microsatellites occurs together with cross-annealing of partially degraded repeated sequences. This could create chimeric alleles that do not correspond to the authentic ones. Here we report a simple method for processing aDNA fragments prior to PCR that greatly reduces the production of chimeric alleles. This approach eliminates aDNA molecules broken within the repeats as targets for Taq polymerase by adding poly(A) tails at the 3(') ends of the DNA fragments, which disrupts the homology in the region and thus prevents annealing out of register. We have analyzed one dinucleotide- (D6S337) and two trinucleotide-containing loci (IT15 and SCA1) using poly(A)-tailed and the same untreated aDNA as template. aDNAs were isolated from 28 human remains, 600 and 7000 years of age. In repeated experiments with untreated aDNAs we obtained three to five times more alleles compared to poly(A)-tailed aDNAs. According to our results, modification of aDNA by poly(A) tailing is an efficient pretreatment for accurate genotyping.