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At least 1,369 records · Page 76Linked to original sources
PubMed2004

[Fluorescence study by simulating the metabolizability of carotenoid and porphyrin during cancer development].

The purpose of the present work was to investigate the effects of carotenoid on the spectroscopic examination of human blood serum by simulating the metabolizability of the carotenoid and porphyrin during the development of cancer and by studying the fluorescence of them. Blood serum was prepared with blood sample from elbow vein and the luminescence center of blood serum was studied using photo induced-luminescence techniques. The major factors of blood serum fluorescence were electron transitions in serological protein, carotenoid and porphyrin molecules with conjugated groups. The intensity of the fluorescence spectrum at 530 nm was enhanced while the minimum intensity at 614 nm was also enhanced with the content of carotenoid increasing, thus the value of diagnostic symbol I decreased, namely the veracity of cancer examination decreased.

Biomarkers, Tumor↗
PubMed2005

Reduced erythrocyte deformability and hypercoagulability in idiopathic sudden sensorineural hearing loss.

OBJECTIVE: Sudden sensorineural hearing loss is a frequent disease whose aetiology is still unknown in about 80% of patients. Aim of this study was to evaluate if haemorheological changes and some indexes of hypercoagulability and hypofibrinolysis are associated with idiopathic sudden sensorineural hearing loss (ISSHL). METHODS: We studied 63 patients with ISSHL and 67 healthy control subjects, matched for age, sex and traditional cardiovascular risk factors. Haemorheological studies were performed by assessing whole blood viscosity (WBV) at 0.512 s(-1) and 94.5 s(-1), plasma viscosity (PLV) and erythrocyte deformability index (DI). To assess whole blood coagulation Sonoclot analysis was performed. Sonoclot variables studied were Sonoclot activated clotting time (SonACT), clot rate and time to peak. Fibrinogen, PAI-1 antigen (ag) and factor VIII:C plasma levels were also measured. RESULTS: WBV, PLV, SonACT, clot rate, time to peak, PAI-1ag and factor VIII:C were significantly altered in patients in comparison with controls (p<0.05). A multivariate analysis (adjusted for traditional cardiovascular risk factors, hematocrit, fibrinogen, haemostatic and haemorheological variables) indicated that WBV at 94.5 s(-1), DI, SonACT, clot rate, PAI-1ag plasma levels and factor VIII:C activity were independently associated with ISSHL (p<0.05). CONCLUSIONS: The observed changes in viscosity, blood clotting and fibrinolysis may contribute, at least in part, to the pathophysiological mechanism of ISSHL.

Adult↗
PubMed2005

Erythrocyte sedimentation rate as a marker of inflammation and ongoing coagulation in stroke and transient ischaemic attack.

OBJECTIVE: Systemic infection and inflammation have been implicated in the aetiology of thrombotic cerebral events, particularly in younger patients. We decided to determine whether those patients with raised D-dimer levels, indicating continuing thrombosis and fibrinolysis, had evidence of concurrent infection or inflammation as manifested by a raised erythrocyte sedimentation rate (ESR) measured after an ischaemic stroke/transient ischaemic attack (TIA). METHODS: One hundred and forty-eight patients who had suffered either single or recurrent cerebrovascular episodes were analysed. The patients were referred to the thrombosis and haemostasis unit at Johannesburg Hospital for evaluation of their thrombotic profiles, including D-dimer levels. Concurrent infection was assessed by measurement of white cell count (WCC) and ESR. The variable time interval between the date of the most recent cerebrovascular event and the date of venesection was determined. A history was taken, a physical and neurological examination was performed, and a cardiology assessment and neuroimaging studies were done. RESULTS: Raised D-dimer levels correlated significantly with ESR levels (p = 0.0094) in all patients. This was particularly evident when comparing the 70 younger patients (aged less than 45 years) with the 78 older patients (> 45 years) with raised D-dimers (p = 0.0070). When analysing other markers of inflammation/infection in association with raised D-dimer levels and ESR, mean fibrinogen levels were significantly raised at 6.56 g/l (p = 0.0122). An elevated WCC, as a categorical variable, was significantly associated with an elevated ESR (p = 0.0092). CONCLUSION: There is a significant correlation between elevated D-dimer levels (indicating abnormalities of coagulation and fibrinolysis) and markers of inflammatory and/or infective processes. This is particularly evident in black patients below the age of 45 years. These patients are believed to be at decreased risk for generalised atheromatous disease compared with older white patients. The ramifications of these findings are potentially important with regard to thrombotic cerebrovascular disease aetiology, investigation, management and prevention.

Adult↗
PubMed2006

Serum tumor markers: part II--practical considerations and limitations of testing.

The attributes of an ideal tumor marker are well beyond the capacity of the tests that are currently available. While some markers do an adequate job at the early detection of recurrence and as a means to monitor the efficacy of treatment, there are serious deficits regarding sensitivity and specificity. In addition, although they are easily measured and cost-effective, the limitations of immunoassays are also a detriment. PSA was used to illustrate many of the limitations and difficulties associated with tumor marker testing and cancer assessment. For the most part, however, it is a better marker than many of the other analytes examined for their corresponding malignancies. Nevertheless, PSA still has major limitations--as is the case for all tumor markers in current use. Although the use of tumor markers is widespread and they do have much to offer, clinicians need to be made aware of their limitations, which can be achieved through good communication between laboratorians and the caregivers who are ordering the tests.

Biomarkers, Tumor↗
PubMed2006

Immunotheranostics: breaking tolerance in immunotherapy using tumor autoantigens identified on protein microarrays.

Cancer patients develop antitumor immune responses, both humoral and cellular, against antigens expressed by their tumors. Low-throughput antigen cloning has been used to identify a number of immunogenic tumor antigens, but this process has limited utility for diagnostics or therapeutic vaccines. A novel approach to the identification of diagnostic antigens that utilizes a combination of high-throughput selection and protein-microarray-based serological detection of complex panels of antigens that are indicative of the presence of cancer, is described herein, and should lead to a great diversity of vaccine candidates. This technology exploits the immune system as a biosensor to diagnose the presence of cancer through serum testing, and the repertoire of antigen biomarkers identified can then be further employed as immunotherapeutic targets. Given the heterogeneity exhibited by tumors, there will be a higher probability of eliciting a cytotoxic antitumor immune response in cancer patients if multiple antigens that are personalized to an individual patient's patterns of autoantibody binding are used for immunotherapy.

Animals↗
PubMed1990

Changes in keratin expression during 7,12-dimethylbenz[a]anthracene-induced hamster cheek pouch carcinogenesis.

This study was undertaken to explore the expression of keratins in the hamster cheek pouch carcinogenesis model, using monospecific keratin antibodies and a technique that allows immunoblotting analysis of tissues embedded in paraffin. Changes in keratin expression were correlated with histopathological changes and with the expression of the enzyme gamma-glutamyl transpeptidase. The right cheek pouch of 20 male golden Syrian hamsters was treated with 0.5% 7,12-dimethylbenz[a]anthracene for 16 weeks. As previously described by other laboratories, this treatment resulted in hyperplastic and dysplastic lesions and benign and malignant tumors. The keratins assayed in this study were K14 (Mr 55,000), K1 (Mr 67,000), and K13 (Mr 47,000). The normal hamster cheek pouch epithelium expressed K14 in the basal layer and K13 in the suprabasal and differentiated layers, whereas K1 was not detected by either immunohistochemistry or immunoblotting. Concomitant with 7,12-dimethylbenz[a]anthracene-induced hyperplasia, there were some topographical alterations in the distribution of K14. In this case, K14 was no longer restricted to the basal layer but was also expressed in differentiated cells. The same pattern was also observed in dysplastic lesions and in squamous cell carcinoma. Furthermore, expression of the K13 differentiation-associated keratin was preserved in this hyperplastic epithelium during all the stages of carcinogenesis, including either anaplastic or differentiated areas. In contrast, after 2 weeks of 7,12-dimethylbenz[a]anthracene treatment, K1 expression started as a weak and patchy pattern in suprabasal cells, becoming stronger and more homogeneous at 8 and 16 weeks of treatment. However, K1 was almost absent in squamous cell carcinoma, where only small very well differentiated areas were stained. We also observed gamma-glutamyl transpeptidase-positive foci in earlier stages of carcinogenesis, concomitant with the expression of the K1 keratin. However, it was not possible to find a perfect topographical correspondence between the two events. Alterations in the pattern of keratin expression appear to be a common feature during the development of squamous cell carcinoma in different systems and could be an excellent tool to study carcinogenesis and chemoprevention.

9,10-Dimethyl-1,2-benzanthracene↗
PubMed2006

Changes in serum cardiac troponins following a 21-km run in junior male runners.

AIM: This study was designed to examine the appearance and clearance characteristics of serum cardiac troponin T (cTnT) and I (cTnI) in junior runners after an exhaustive 21-km run. The dependence of the alternations of the cardiac troponins on the runners' training status reflected in training years, running ability and physiological profile at ventilatory threshold (Th(vent)) was also examined. METHODS: Ten trained male adolescents (16.2+/-0.6 years) performed 21-km run and graded treadmill exercise with maximum effort on two different days. cTnT and cTnI immediately before and 2, 4 and 24 hours after exercise were measured in the 21-km trial. The parameters at Thvent including the running speed (Th(vent)-Speed) and VO2 (Th(vent)-VO2) were identified in the graded exercise trial. RESULTS: Serum cTnT and cTnI in 6 of the 10 subjects measured 4 hours after the 21-km run were above the myocardial injury cutoffs of 0.03 and 0.09 ng x mL(-1), respectively, but returned towards pre-exercise levels within 24 hours that were not in the same manner observed in the clinical situation of myocardial infraction. The 6 subjects' training status was generally lower than that of the rest 4. Further, subjects' 4-h serum cTnT and cTnI were negatively related to their training years, Th(vent)-Speed and Th(vent)-VO2, and positively related to their personal best in half- and full-marathon races (r2 = or > 36%, n = 10). CONCLUSIONS: Such findings implied that clinicians based the diagnosis of long-distance run-induced myocardial infraction in novice junior runners upon the transient postexercise elevations of cardiac troponins alone should be with caution.

Adolescent↗
PubMed2006

Status of iodine nutrition in pregnant and lactating women in national capital district, Papua New Guinea.

Urinary Iodine excretion is a useful and important indicator of the iodine status of a population. This study attempts to determine the urinary iodine concentration of non-pregnant, pregnant and lactating women, resident in the National Capital District of Papua New Guinea, so as to evaluate their status of iodine nutrition. The study population was made up of 56 non-pregnant, 40 lactating and 212 pregnant women. Of the 212 pregnant women, 14 were in the first, 64 in the second, and 134 in the third Trimester of pregnancy. Casual urine samples were collected and analysed for urinary iodine by Sandell-Kolthoff reaction. The median urinary iodine concentration for the non-pregnant, lactating and pregnant women was 163.0 micro g/L, 134.0 micro g/L and 180.0 micro g/L, respectively. Median urinary iodine for the first, second and third trimesters were 165.0 micro g/L, 221.5 micro g/L and 178.0 micro g/L, respectively. The 20th percentile urinary iodine values were higher than 50 micro g/L for all the groups. This indicates adequate intake of dietary iodine and optimal status of iodine nutrition amongst women in the various groups. Mild to severe status of iodine nutrition was found in 30.4% of non-pregnant, 35.0% of lactating, 22.2% of pregnant women, 28.5% of women in the first, 18.8% in the second, and 23.1% in the third trimester of pregnancy. To achieve optimal iodine nutrition in pregnant and lactating women, an increase in their intake of dietary iodine is recommended.

Adult↗