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91.
OBJECTIVES: The objective of this prospective study is to establish an appropriate cutoff value of urinary CYFRA 21.1 assay and to assess its utility combined with voided cytology and/or haemoglobin dipstick in the follow-up of patients with superficial bladder cancer. METHODS: From December 2000 to November 2003, 446 patients in follow-up for superficial bladder cancer (Ta-T1) after transurethral resection of the bladder (TURB) were included in a prospective study. Voided urine specimens were collected 7-14 d before cystoscopy and/or TURB for CYFRA 21.1 (one sample), haemoglobin dipstick (one sample), and cytology (three samples). All samples were processed for CYFRA 21.1 and haemoglobin dipstick according to manufacturer instructions. A control group (n=185) was obtained from patients in follow-up after transurethral resection of superficial disease (without recurrences within the following 6 mo). There were 125 recurrent transitional tumours detected by cystoscopy (34 TaG1; 53 TaG2/T1G1-2; 23 Ta-1G3/Tis, and 15 T2-4). Receiver operator characteristic (ROC) curves were constructed and cutoff values were chosen. Sensitivity, specificity, PPV (positive predictive value), NPV (negative predictive value), and their 95% confidence intervals were calculated. RESULTS: ROC curve analysis based on the previously reported cutoff value of 4ng/ml for CYFRA 21.1 demonstrated a sensitivity and specificity of 43% and 68%, respectively. At a cutoff value of 1.5ng/ml, sensitivity was 73.8% with a low specificity (41%). Further lowering of the cutoff point below 1.5ng/ml did not demonstrate a significant increase in sensitivity. Therefore, this value was chosen as the most sensitive CYFRA 21.1 cutoff point during the rest of the study. Specificity increased when all the patients treated with pelvic radiotherapy or with UTI, urethral catheterisation, and intravesical instillations within 3 previous months were not included in our analysis. CYFRA 21.1 plus cytology and the combination of CYFRA 21.1, cytology, and haemoglobin dipstick demonstrated the highest overall sensitivities, and detected 91.3% of Ta-1G3 tumours and 93.3% of T2-4 tumours. However, there were one muscle-invasive tumour, two T1G3/Tis, three T1G2, and nine T1G1 neoplasms with negative combination of cytology and CYFRA 21.1 (1,5ng/ml). All these tumours were smaller than 2cm in size; most were single tumours. Nevertheless, there were 16 tumours larger than 0.5cm (0.5-2cm), and multiple neoplasms were endoscopically detected in 14 patients. Similar results were obtained through the combination of CYFRA 21.1 (cutoff: 1.5ng/ml), cytology, and haemoglobin dipstick. CONCLUSIONS: In our experience the low sensitivity of urinary CYFRA 21.1, even using lower cutoff values and/or a combination with cytology and/or haemoglobin dipstick, makes its application not very useful as a surveillance tool for superficial bladder carcinoma.  相似文献   
92.
Amphiphilic ABCBA pentablock copolymers based on PVP, PS, and PDMS were synthesized using a combination of ATRP and RAFT polymerizations. The PVP‐block‐PS‐block‐PDMS‐block‐PS‐block‐PVP pentablock copolymer was characterized using a variety of chromatography and spectroscopic methods which showed that a high degree of end group and molecular weight control can be achieved. Preliminary analysis of the aqueous solution behavior of the pentablock copolymer showed that it self‐assembles in water in order to shield the PDMS and PS segments from the water.

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93.
Vaginal Lactobacillus salivarius CRL 1328 (Centro de Referencia para Lactobacilos Culture Collection) or the bacteriocin that produces could be included in a urogenital probiotic formula to prevent urogenital infections in women. The objective of this work was to determine the effects of different carbon and nitrogen sources on the growth and bacteriocin production of this microorganism. A fractional factorial design 35–1 was applied to evaluate the effects of five nutrients (glucose, lactose, yeast extract, tryptone and meat peptone), at three different concentrations (0, 1 and 2%). Results were statistically analyzed for linear and quadratic effects of nutrients, along with their interactions. All the nutrients tested stimulated the cell growth and bacteriocin production, but lactose had not a significant influence on the last response. The linear effects of higher magnitude on biomass and bacteriocin production were those of yeast extract and tryptone. The results demonstrated that there were significant interactions between the different nutrients, depending on the response evaluated. Maximum bacteriocin production was reached in different growth media with a lower cost than conventional culture media used in the laboratory. These findings will contribute to the design of a pharmaceutical product for the restoration of ecological balance of urogenital tract. (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)  相似文献   
94.
Consumer acceptability and sensory properties of liquorice root (Glycyrrhiza glabra L.) were evaluated. Quantitation of total polyphenolics and glycyrrhizic acid (GA), as well as the antioxidant capacity of liquorice extracts, was conducted and their biological effects (cytotoxic, antioxidative/pro-oxidative activity, lipid peroxidation on human laryngeal carcinoma cell line) compared to the ones of their predominant bioactive compound – GA. Conducted consumer survey revealed poor familiarity with liquorice (12.37% of correspondents), but willingness towards its use as an alternative sweetener (77.32% of consumers). Polyphenolic content of evaluated extracts ranged from 1018.18 to 1277.27?mg gallic acid equivalents (GAE)/l while GA content varied between 2179.53 and 2944.13?mg/l. The most pronounced cytotoxic effect (60%) and lipid peroxidation were exerted by treatment with the highest applied extract concentrations (10?mg/ml). Pure GA exhibited cytotoxic and pro-oxidative effects at concentrations of 0.12–0.6?mg/ml. Due to high GA content, coupled with its pronounced cytotoxic activity, the intake of liquorice root should be limited.  相似文献   
95.
Recent data suggest that childhood and adulthood stressors may play a significant role in the development of an autoimmune disease. The present study explores the relationship between psoriatic arthritis (PsA) and positive and negative life events during childhood and adulthood in psoriatic patients. Forty-five patients with psoriatic arthritis and 101 controls (patients with skin conditions considered to be “non-psychosomatic”) were enrolled in the study. All participants completed a specific questionnaire measuring traumatic life experiences [Traumatic Antecedents Questionnaire (TAQ)]. The TAQ assesses positive personal experiences (competence and safety) and negative personal experiences (neglect, separation, secrets, emotional, physical and sexual abuse, trauma witnessing, other traumas and exposure to alcohol/drugs) from early childhood to adulthood. The patients with psoriatic arthritis exhibited lower mean scores of total positive experiences during late childhood (latency) as compared to the control group. Negative experiences during four developmental periods appeared more frequently in patients with psoriatic arthritis than in the controls. The most frequently reported negative experiences were neglect, emotional abuse, physical abuse, sexual abuse, alcohol/drug abuse and other traumas. The present findings add evidence to the relationship between retrospectively reported childhood experiences and psoriatic arthritis. Furthermore, a high amount of reported emotional and physical abuse occurs in patients with psoriatic arthritis during latency and adolescence.  相似文献   
96.
In this article, the bioactive potential of red raspberry leaves, a by-product of this widely spread plant, mostly valued for its antioxidant-rich fruits, was determined. The polyphenolic profile and antioxidative properties of red raspberry leaf extract were determined and examined for potential biological activity. Cytotoxic effect, antioxidative/prooxidative effect, and effect on total glutathione concentration were determined in human laryngeal carcinoma (HEp2) and colon adenocarcinoma (SW 480) cell lines. SW 480 cells are more susceptible to raspberry leaf extract in comparison with HEp2 cells. The antioxidative nature of raspberry leaf extract was detected in HEp2 cells treated with hydrogen peroxide, as opposed to SW 480 cells, where raspberry leaf extract induced reactive oxygen species formation. Raspberry leaf extract increased total glutathione level in HEp2 cells. This effect was reinforced after 24 hours of recovery, indicating that induction was caused by products formed during cellular metabolism of compounds present in the extract. Comparison of the results obtained on these two cell lines indicates that cellular response to raspberry extract will depend on the type of the cells that are exposed to it. The results obtained confirmed the biological activity of red raspberry leaf polyphenols and showed that this traditional plant can supplement the daily intake of valuable natural antioxidants, which exhibit beneficial health effects.  相似文献   
97.
Spin density projection‐assisted R2‐magnetic resonance imaging (R2‐MRI; FerriScan®) scans from 40 chelation‐naïve sickle cell patients were used to assess renal iron load by measuring renal R2 (R‐R2). Clinical data were collected retrospectively for the 2‐year period preceding the scan. R‐R2 showed no significant correlation with transfusional iron load (assessed by liver iron concentration), but correlated significantly with serum bilirubin (R = 0·61, P < 0·0001) and lactate dehydrogenase (R = 0·58, P < 0·0001). Mean (±standard deviation) R‐R2 was higher (P = 0·02) in patients with renal hyperfiltration (29·8 ± 10·3/s) than those without (23·11 ± 6·6/s). Five patients had significantly lower signal intensity in the renal cortex, as compared to the medulla. These patients had a significantly higher (P < 0·0001) mean R‐R2 than those showing no cortico‐medullary difference. We postulate that the increased R‐R2 is associated with haemolysis rather than transfusional iron load in sickle cell disease.  相似文献   
98.
99.
Sanja Drača 《Autoimmunity》2013,46(5):307-312
Pregnancy and parturition are the physiological conditions that affect the course and severity of numerous autoimmune diseases. If genotype might be primarily considered as a determinant of whether or not autoimmunity develops, clinical heterogeneity of the disease might arise from the interaction of the genotype and the environment. Numerous external factors with extremely important immunoregulatory properties, including hormones, affect an in vivo open complex immune system. The further investigation of the role of neuroendocrine-immunological network, including a pregnancy-associated immunomodulation, as much as the role of "causative" or "trigger" agents, may allow the rational basis of new alternative treatment of numerous autoimmune diseases.  相似文献   
100.
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