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PubMed2001

[Correlation between corneal topography and subjective refraction in idiopathic and surgery-induced astigmatism].

PURPOSE: To study the correlation between subjective refraction and corneal topography. To compare the topographic analysis of surgically induced astigmatism (cataract and penetrating keratoplasty) with that of idiopathic astigmatism. METHODS: Subjective astigmatism, subjective spherical equivalent, best spectacle-corrected visual acuity (LogMAR units), and videokeratoscopy using the EyeSys 2000((R)) device (axial, tangential, and refractive power) were recorded in 100 eyes with idiopathic astigmatism, 100 eyes after cataract surgery, and 100 eyes after penetrating keratoplasty. Topographies were classified according to pattern (Bogan classification) and asphericity (shape factor: prolate or oblate). RESULTS: The asphericity shape distribution was significantly different between the 3 groups (p<0.001). The shape of idiopathic astigmatism was almost always prolate (90%) whereas the oblate shape was more frequent in the penetrating keratoplasty group (75%). There was no significant difference in topographic pattern distribution between the 3 groups (p=0.11). The asymmetric bow tie pattern was the most common topographic pattern. Topography pattern classification was significantly correlated with the subjective astigmatic cylinder. (r(s)=0.60, p<0.001). Unlike the round and oval patterns, the bow tie pattern was associated with the high subjective cylinder. Correlation between the subjective cylinder, the refractive power cylinder, and the axial power cylinder was strong (r(s)=0.92 p<0.001), but it was weak for the tangential power cylinder (r(s)=0.72 p<0.001). The correlation between the subjective spherical equivalent and central cornea power was poor (r(s)<0.37, p<0.001). Subjective astigmatic cylinder showed the strongest correlation with best spectacle-corrected visual acuity (r(s)=0.70, p<0.001), whereas the predicted corneal acuity, corneal uniformity index, asphericity, and refractive power symmetry index were poorly correlated with it (r(s)<0.54, p<0.001). CONCLUSION: Despite the difference in the asphericity shape, the topographic pattern was similar in the 3 groups. The pattern type was significantly correlated with the subjective astigmatic cylinder. Topographic indices failed to predict visual acuity, while the subjective cylinder showed a strong correlation with visual acuity.

Astigmatism↗

PubMed2000

Serial neuro-electrophysiological studies in acute organophosphate poisoning--correlation with clinical findings, serum cholinesterase levels and atropine dosages.

OBJECTIVES AND METHODS: A prospective evaluation of the correlation between the serial clinical findings, serum cholinesterase levels, electrodiagnostic abnormalities and the daily atropine requirement was undertaken in 29 patients with confirmed acute organophosphate poisoning (OPP). RESULTS: Clinical weakness conforming to the pattern found in 'Intermediate Syndrome' was noted in 19 patients (65.55%). It was associated with all types of organophosphate compounds and occurred in all patients in whom the serum cholinesterase on admission was less than 200 units. Three types of electrodiagnostic abnormalities were noted: single supramaximal electrical stimulus induced repetitive response, a decrement--increment response to 30 Hz repetitive nerve stimulation (RNS) and a decremental responses to 30 Hz RNS. The 30 Hz decremental response correlated best with the presence of clinically detectable weakness (sensitivity = 61.72%; specificity = 81.54%; positive predictive value = 73.91%; negative predictive value = 71.62%). Time trends evaluation revealed that the peak daily atropine dosages were given at a mean of 1.76 +/- 0.83 days in comparison to a mean nadir of serum cholinesterase of 2.48 +/- 1.97 days and a mean nadir of 9:1 ratio of 2.65 +/- 1.76 days. The 2-tailed correlation coefficient analysis and simple regression analysis revealed a positive correlation between serum cholinesterase levels and the 9:1 ratios (correlation coefficient: 0.59). A negative correlation was observed between the 9:1 ratios and the daily atropine requirement (correlation coefficient: -0.57) and between serum cholinesterase levels and daily atropine requirement (correlation coefficient: -0.49). CONCLUSIONS: At admission, level of serum cholinesterase of less than 200 units is a predictor and the 30 Hz RNS decremental response could be a useful marker for the 'Intermediate Syndrome'.

Acetylcholinesterase↗

PubMed2001

Expression of DT-diaphorase and cytochrome P450 reductase correlates with mitomycin C activity in human bladder tumors.

Mitomycin C (MMC) is activated by DT-diaphorase (DTD) and cytochrome P450 reductase (P450R). In cancer cell lines, MMC cytotoxicity is correlated with DTD and P450R expression levels. The present study investigated the relationship between enzyme expression/activity and MMC cytotoxicity in patient bladder tumors. DTD and P450R expression was detected by competitive reverse transcription-PCR and their activity was measured by bioreductive assays. The expression of DTD and P450R in patient tumors (n = 29), as ratios to beta-actin levels, varied from 0 to 90% and 0 to 29%, respectively. The DTD expression was significantly correlated with P450R expression (r(2), 0.32; P < 0.01), whereas the average DTD level was 2-fold higher than that of P450R (P < 0.01). Among the 29 tumors, 21 provided sufficient materials to evaluate tumor sensitivity to MMC. The concentration of MMC required to produce 50% inhibition (IC(50)) of DNA precursor incorporation for a 2-h treatment ranged from 0.17 to 18.1 microg/ml, indicating a 110-fold intertumor variation, with the high-grade and more invasive tumors being less chemosensitive compared with the low-grade and less invasive tumors. Tumor sensitivity to MMC, as indicated by the inverse of IC(50) values, was positively correlated with the expression of DTD (r(2), 0.28; P < 0.05) and P450R (r(2), 0.26; P < 0.05). Multivariate analysis indicates DTD expression and P450R expression as better determinants of MMC activity compared with other pathobiological factors (e.g., tumor grade, stage, and labeling index) that have been shown to significantly correlate with MMC activity. Eleven tumors were studied for the relationship between gene expression level and enzyme activity of DTD and P450R. The DTD activity was significantly correlated with the gene expression level (r(2), 0.84; P < 0.001). For P450R, there is a trend of a correlation between enzyme activity and its mRNA level, but the correlation was not statistically significant (r(2), 0.28; P = 0.09). These data indicate that the sensitivity of patient bladder tumors to MMC is correlated with the expression of DTD and P450R in tumors and suggest that the lower expression of these enzymes in the high-grade and more invasive tumors is a cause of the lower efficacy of intravesical MMC in these tumors.

Adult↗

PubMed2000

Erythropoiesis: Correlations Between Iron Status Markers During Normal Pregnancy in Women with and without Iron Supplementation.

The aim was to evaluate relationships between iron status markers (haemoglobin, erythrocyte indices, serum iron, serum transferrin, serum transferrin saturation, serum ferritin) in normal pregnancy. Iron status markers were measured at 4-week-intervals during pregnancy and postpartum in 120 healthy women; 62 had daily treatment with tablets containing 66 mg ferrous iron, 58 were treated with placebo. Placebo-treated: Ferritin displayed positive correlations with transferrin saturation during 2nd and 3rd trimester. There were positive correlations between ferritin, erythrocyte MCV and MCH during 2nd and 3rd trimester and postpartum. Prior to delivery and postpartum, ferritin demonstrated positive correlations with haemoglobin. Transferrin saturation showed positive correlations with MCV, MCH and MCHC during 2nd and 3rd trimester and postpartum. Transferrin saturation displayed positive correlations with haemoglobin prior to delivery and postpartum. Iron-treated: In general, there were no correlations between iron status markers. Positive correlations appeared postpartum between ferritin, transferrin saturation and MCHC but not with haemoglobin. Transferrin saturation showed a positive correlation with MCH postpartum, but not with haemoglobin. Conclusion: The patterns of relationships in placebo-treated women were consistent with iron deficient erythropoiesis.

Journal Article↗

PubMed2001

Correlations between microbial parameters from water samples: expectations and reality.

Data which are collected in order to estimate the correlation between parameters must be analysed with caution. Classical statistics of correlation are often inappropriate. The "r" statistic is very easily distorted by non-Normal data. Non-parametric statistics can be helpful. The interpretation and usefulness of the estimates of correlation will depend on the study plan. If water samples come from disparate sources (e.g. upstream or downstream from sewage outlets) then parameters A and B may occur in their highest and lowest numbers according to how close the samples were to contamination sources thus correlating closely. However, if all samples come from sources with similar pollution levels then plots of A and B will show considerable scatter and apparently little correlation. So what is the relationship between A and B? An example of "perfect" correlation, as demonstrated by replicate counts of a single parameter from split samples, gave an r value of only 0.63 (p = 0.62) due to random variation in numbers of organisms between the two halves of the sample. Thus large amounts of data are needed for studying true correlation because relationships between parameters are embedded in the natural variation. This also illustrated that Standards for a single parameter can be "passed" or "failed" by two halves of the same sample. Study design is clearly of fundamental importance. Consideration must be given to the appropriate way of asking questions about correlation between different parameters.

Data Collection↗

PubMedDate not supplied

[Correlation between survival time and severity of injuries in fatal injuries in traffic accidents].

INTRODUCTION: In forensic pathology, only trauma systems based on disintegration of anatomic structure of organs and tissues, could be used for objectivization, comparison and establishing of severity of injuries. Trauma systems based on pathophysiological values are useless. The Abbreviated Injury Scale (AIS) and its derivate Injury Severity Score (ISS) are the most common. AIS coded injuries are divided into six body regions and injuries are assigned a six-digit score in relation to their severity. ISS results the sum of the squares of the highest AIS values from the three most severely injured body regions. In this way, the ISS values are discontinued and vary from 0 (absence of injuries) to 75 (incompatible-with-life injury). PURPOSE: The purpose of this paper is to establish the correlation degree between outliving period and trauma severity in persons fatally injured in traffic accidents, and according to this finding to point out the ISS value of critical injury. MATERIAL AND METHOD: A retrospective autopsy study was performed; it included the material of the Institute of Forensic Medicine in Belgrade of 1998. The autopsy reports and accessible clinical medical data were analyzed for persons over the age of 18, fatally injured in traffic accidents who survived trauma less than 15 days. The sample was statistically prepared (chi 2-test, t-test, correlation coefficient, regression line). RESULTS AND DISCUSSION: The sample included 272 persons: 193 males and 79 females. The proportion of men was more significant (chi 2 = 4.76; 0.01 < p < 0.05). Average age was 51.08 years (SD = 18.08): males 49.84 +/- 17.41 and females 54.09 +/- 19.38. The most frequently injured persons in our sample were pedestrians (134). The authors combined the autopsy and accessible clinical data in order to obtain the ISS value for each case. They considered that all persons found dead on the spot or died ante portam did not outlive trauma. The sample distribution by ISS values showed three peaks: for ISS--75, 41-50 and 26-35. Peaks indicated the number of the injured body regions and trauma severity in these persons. In 87 persons who did not survive, the ISS value was 75. There were 73 persons without outliving period with ISS values less than 75: their mean ISS value was 31.87 (SD = 11.30). In 112 cases the mean outliving period was 4.79 days (SD = 3.77) and their mean ISS value was 18.05 (SD = 15.33), which was a statistically significant lower ISS value than in previous group (t = 7.015; p < 0.001). A weak negative correlation between outliving period and ISS values in our sample was noted (coefficient of linear correlation r = -0.452). Our sample is representative (t = 8.37). Coefficient of a determination (r2 = 0.20), pointed to the fact that direct correlation outliving period-trauma severity was only about 20% and the rest of correlation i.e. 80% depended on other factors (e.g. effective emergency medical system and triage, prompt and correct diagnosis, adequate medical treatment and care, etc.). The calculated linear regression was as follows: outliving period approximately 52-3 ISS. This regression pointed out that critical and potentially fatal injury, in our sample, was injury with ISS of 17. There were 22 persons with ISS < or = 7. Six of them died on the spot as car passengers; they died due to mechanical asphyxia (thoracoabdominal pressure) or respiratory and/or circulation failure due to critical chest injury (flail chest, contusions and rupture of the lungs with consequent haemopneumothorax). The rest of 16 persons survived trauma in an average of 8.56 days (SD = 3.88), and the causes of death were pneumonia, thrombus and fat embolism, sepsis, etc. CONCLUSION: By anaylzing our sample of fatally injured persons in traffic accidents (unpenetrated blunt trauma), there was a negative weak correlation between the outliving period and severity of injury based on ISS. This correlation was partly direct but mostly depended on other factors (e.g. effective emergency medical system and triage, prompt and correct diagnosis, adequate medical treatment and care, etc.). Establishment of these factors could be possible through state medical projects in big medical trauma centres. Prospect registration, evaluation and scoring of all injuries in hospitals and dissecting rooms, and comparison of the obtained results, can give valid data on mortality of injured people, bad diagnosis, and appropriate medical treatment. The autopsy of injured persons dead on the spot can point out what kind of injuries are incompatible with life, as well as with their severity. The autopsy of injured persons who survived trauma can point to the most frequent injury complications, clinical diagnosis and preventable deaths. According to this paper, the critical injury by ISS is 17. In such cases, the forensic pathologist must answer the following questions: whether the death was due to trauma; whether the precipitated cause of death was the consequence or complication of injury; what were the mechanism and mode of dying; whether the death was preventable; if there were possible malpractice and negligence, etc.

Accidents, Traffic↗

PubMedDate not supplied

Correlation between tremor parameters.

The relationship between clinically scored tremor and electromyographic measurements of tremor amplitude is not clear and few reports have examined correlations between different tremor parameters. The aim of this study was to evaluate the correlations between different tremor parameters, clinical tremor scoring, age and disease duration. A total of 525 patients with different types of tremor were included in this study. Tremor in various limb positions was graded according to the Webster Tremor Scale. Surface electromyographic recordings of the limb found, in each position, to be most involved were performed in all the patients. The Spearman rank correlation coefficient was used to analyse the relationship between clinical and electromyographic parameters, while the Pearson correlation coefficient was used to analyse the relationship between the electromyographic parameters. Our results revealed moderate correlation between tremor amplitude as measured by electromyography and Webster tremor scores. The correlation between different tremor parameters revealed that low frequency tremors have higher amplitude, and longer burst duration, interval between bursts and missing interval. As the disease progresses, the tremor amplitude increases, while the frequency decreases. A strong positive correlation emerged between corresponding tremor parameters in different limb positions. This suggests that the tremor in all limb positions is generated by the same oscillator. In conclusion, a good correlation was found between clinically scored tremor and EMG measurements of tremor amplitude. The electromyographic examination is a useful tool for researching tremor mechanisms.

Age of Onset↗

PubMed2002

Transforming growth factor-beta1 in fetal serum correlates with insulin-like growth factor-I and fetal growth.

OBJECTIVE: To estimate whether transforming growth factor-beta1 in fetal serum obtained by umbilical cord sampling at delivery is correlated with fetal growth. We also estimated whether transforming growth factor-beta1 is correlated with insulin-like growth factor-I and insulin-like growth factor binding protein-1, which have been shown to correlate with fetal growth. METHODS: The active form of transforming growth factor-beta1 was analyzed in serum from cord blood from 68 fetuses by the enzyme-linked immunosorbent assay technique. Of the 68 pregnant women, 12 had preeclampsia, 14 had preeclampsia and intrauterine growth restriction, 15 had intrauterine growth restriction alone, and seven had fetuses that were large for gestational age (LGA). Twenty pregnancies with fetuses appropriate for gestational age (AGA) served as controls. RESULTS: Transforming growth factor-beta1 concentrations were significantly correlated with birth weight. The average transforming growth factor-beta1 concentration in the following groups were: intrauterine growth restriction, 22.4 +/- 2.7 microg/L; intrauterine growth restriction plus preeclampsia, 22.9 +/- 2.0 microg/L; preeclampsia without intrauterine growth restriction, 28.8 +/- 2.1 microg/L; LGA, 30.3 +/- 4.3 microg/L; and AGA, 36.8 +/- 2.0 microg/L. Transforming growth factor-beta1 levels were significantly lower in pregnancies complicated by intrauterine growth restriction and showed a positive correlation with birth weight (r = 0.48, P <.001). Furthermore, there was a positive correlation between insulin-like growth factor-I levels and birth weight (r = 0.36, P <.01) and a negative correlation between insulin-like growth factor binding protein-1 and birth weight (r = -0.32, P <.01). There was also a correlation between transforming growth factor-beta1 and insulin-like growth factor-I (r = 0.29, P <.05) and between transforming growth factor-beta1 and insulin-like growth factor binding protein-1 (r = -0.25, P <.05). CONCLUSION: Transforming growth factor-beta1 might be related to fetal growth in pregnancy. The results also support previous data showing that insulin-like growth factor-I and insulin-like growth factor binding protein-1 are related to fetal growth.

Adult↗

PubMed2003

[The correlation of Child-Pugh score, PGA index and MELD score in the patient with liver cirrhosis and hepatocellular carcinoma according to the cause of alcohol and hepatitis B virus].

BACKGROUND/AIMS: To determine the treatment modalities and the prognosis of a patient with liver cirrhosis, quantitative estimation of liver function is important. We assessed the Child-Pugh score (CPS), the common method as a severity index for the cirrhosis, the Prothrombin, gammaGT, and Apolipoprotein A1 (PGA) index and model for end-stage liver disease (MELD) score. The purpose of this study was to evaluate the correlation between these indices in the patients with cirrhosis only and hepatocellular carcinoma (PHC), according to underlying causes (HBV and alcohol). METHODS: We reviewed medical records of 339 cirrhotic patients with/without hepatocellular carcinoma and divided patient groups by disease and underlying cause: cirrhosis caused by alcohol; LC-Al, cirrhosis caused by HBV; LC-B, hepatocellular carcinoma with cirrhosis caused by alcohol; HCC-Al, hepatocellular carcinoma with cirrhosis caused by HBV; HCC-B. We assessed the CPS, PGA index and MELD score and calculated the correlation coefficient between these scores. RESULTS: Among the total of 339 patients, 201 patients were diagnosed on the liver cirrhosis only, and 138 patients on the hepatocellular carcinoma with cirrhosis. In each groups, mean score values were not significantly different in CPS, PGA index and MELD score. The correlation of CPS, PGA index and MELD score in all groups, except for the correlation of PGA index and MELD score in HCC-Al group, was significantly positive (p<0.05). Compared to correlation coefficients between three indices, the patients with cirrhosis only had higher tendencies than the patients with hepatocellular carcinoma. The patients by HBV had higher tendencies than by alcohol. CONCLUSIONS: The correlations between CPS, PGA index and MELD score showed significantly positive correlations in the patients with liver cirrhosis only and hepatocellular carcinoma with cirrhosis (except in HCC-Al group). The patients with cirrhosis only had higher correlation coefficients than the patients with PHC and the patients by HBV had higher than by alcohol.

Adult↗

PubMed2003

[Quality of life assessment with the use of the SF-36 in patients with nasal polyposis: correlations with clinical and laboratory findings].

OBJECTIVES: We evaluated the quality of life of patients with nasal polyposis and sought correlations between clinical and laboratory parameters and quality of life. PATIENTS AND METHODS: Thirty-two patients (8 females, 24 males; mean age 43 years; range 15 to 68 years) with nasal polyposis were evaluated by history, physical examination, endoscopy, computed tomography (CT), nasal smear, and skin prick tests. Quality of life was assessed using the Medical Outcomes Study Short Form 36 (SF-36). RESULTS: The mean CT score showed a weak correlation with symptom and endoscopic scores (p<0.05), whereas the latter two scores were not correlated. All the SF-36 scales were adversely influenced, particularly including the scores for role limitation caused by emotional problems, general perception of health, vitality, and role limitation caused by physical problems. An inverse correlation was found between increasing age and complaints of pain (p<0.05). Symptom scores were correlated only with role limitation caused by emotional problems (p<0.05). Duration of nasal symptoms was correlated with increased scores for role limitation caused by physical problems, mental health, social functioning, and pain (p<0.05). Computed tomography stage was correlated with role limitation caused by emotional problems, pain, and social functioning, whereas CT scores showed correlation only with pain (p<0.05). The presence of asthma adversely influenced general perception of health scores (p<0.05). CONCLUSION: Nasal polyposis adversely affects the quality of life of patients, the extent of deterioration being more prominent in certain subscales.

Adolescent↗

PubMed2004

[The expression of platelet-derived growth factor (PDGF) receptor-beta and its correlation with extracellular matrix in hepatic tissue in hepatic fibrosis rats].

OBJECTIVE: To investigate the expression of PDGF receptor-beta and its correlation with extracellular matrix in hepatic tissue during hepatic fibrosis. METHODS: The model of hepatic fibrosis in rats was induced by carbon tetrachloride. PDGF receptor-beta subunit, collagen I, collagen III and a-SMA in hepatic tissues of these rats were examined using immunohistochemistry. The correlation between PDGF receptor-beta subunit and collagen I, III was analyzed using SAS software after the results of immunohistochemistry were semi-quantified. RESULTS: PDGF receptor-beta subunit and a-SMA were not detected in normal controls. Collagen I and III were distributed in the portal tracts and beneath the endothelia of the central veins and of the Disse spaces. Two weeks after CCl4 injection, the PDGF receptor-beta and a-SMA were detected, and the expression of collagen I and III increased. At the end of 4 and 6 weeks, the above four proteins were further increased. Two weeks after CCl4 injection, PDGF receptor-beta had no apparent correlation with collagen I and III. However, PDGF receptor-beta had a significant correlation with collagen I and III 2 weeks later, and the correlation coefficient was 0.74 and 0.60 respectively at 4 weeks, and 0.83 and 0.67 respectively at 6 weeks. PDGF receptor-beta had a significant correlation with a-SMA during the whole process of hepatic fibrosis and the correlation coefficient was 0.62, 0.69 and 0.81, respectively at the time of 2, 4 and 6 weeks after CCl4 injection. CONCLUSION: The PDGF receptor-beta was overexpressed during the process of hepatic fibrosis development, and it significantly correlated with collagen I and collagen III.

Animals↗

PubMedDate not supplied

[Correlations between cognition and function in Alzheimer's disease: based on the abbreviated Barcelona Test (a-BT)].

INTRODUCTION: The objective is to establish the existence of possible correlations between cognitive measures using the a-BT, and functional measures in a population of normal to moderately severe demented subjects. METHODS: A sample of 107 subjects (42 healthy controls, 19 subjects with mild cognitive impairment and 46 patients with probable Alzheimer's disease) were included in the present study. The instruments of the cognitive measure used was the abbreviated Barcelona Test (a-BT), a test of general cognitive function. Apart from that, the following functional scales, evaluating activities of daily living, were used: Rapid Disability Rating Scale-2 (RDRS-2), Blessed Dementia Rating Scale (BDRS), and Interview for Deterioration in Daily living in Dementia (IDDD). The statistical procedures were the correlations between cognitive and functional measures using Pearson's correlation coefficient. RESULTS: The correlations obtained between the cognitive and all functional measures were all highly significant (p < 0.0001) and consistently high, with correlations ranging between 0.72 and 0.80. Correlations between the a-BT and functional measures of more basic activities of daily living (RDRS-2, BDRS) were lower than those that included instrumental and some advanced activities of daily living (IDDD). DISCUSSION: The present paper establishes the existence of satisfactory correlations between the functional measures studied and the global scores of the a-BT. These correlations are applicable for groups of subjects with cognitive impairment that does not reach the threshold of a diagnosis of dementia as well as subjects suffering from Alzheimer's disease, at least up to moderately severe cases. The global score of the a-BT allows for some degree of prediction of the functional status of a subject with suspected Alzheimer's disease pathology evaluated.

Activities of Daily Living↗

PubMed2005

[Dust storms trend in the Capital Circle of China over the past 50 years and its correlation with temperature, precipitation and wind].

The trends of number of dust storm days of the selected 11 meteorological stations from their established year to 2000 as well as their correlations with temperature, precipitation and wind are revealed. The number of dust storm days of the Capital Circle of China is distinctly variable in space and time. The numbers of dust storm days of the western area are far more than those of the eastern area. The interannual variability of number of dust storm days is remarkable. The number of dust storm days of the following 7 stations, Erlianhaote, Abaga, Xilinhaote, Fengning, Zhangjiakou, Huailai and Beijing, declined along the past decades, but those of the other four stations had no significant upward or downward trends. There is a marked seasonality of the number of dust storm days, and the maximum was in April. The correlation between number of dust storm days and number of days of mean wind velocity > 5 m/s, which is critical wind velocity to entrain sand into the air, was strongest among the three climatic factor. There were significant positive correlations between the number of dust storm days and number of days of mean wind velocity > 5 m/s in 6 stations. The second strongest climatic factor correlated with the number of dust storm days is temperature. There are significant negative correlations between the number of dust storm days and mean annual temperature, mean winter temperature, mean spring temperature in 3 or 4 stations. The correlation between the number of dust storm days and precipitation is weakest. Only one station, Zhurihe, showes significant negative correlation between the number of dust storm days and spring rainfall. There are 4 stations whose number of dust storm days don't significantly correlate with the climate. In the end, the spatial-temporal variability of dust storms and its relation with climate in the Capital Circle of China were discussed thoroughly.

Air Pollutants↗

PubMed2005

[Correlations of telomere length and telomerase activity to radiosensitivity of human laryngeal squamous carcinoma cells].

BACKGROUND & OBJECTIVE: Many studies showed that telomere length and telomerase activity closely correlate with proliferation and malignant degree of tumor cells, and both of them might be involved in the repair of radiation-induced DNA damage. So it was speculated that telomere length and telomerase activity maybe correlate to radiosensitivity of carcinoma cells. This study was designed to investigate the correlations of telomere length and telomerase activity to radiosensitivity of human laryngeal squamous carcinoma cell line Hep-2. METHODS: Hep-2 cells were irradiated with 0, 2, 4, 8, or 12 Gy of gamma-ray for 3 times. Survival cells were subcultured for 20 generations. Radiosensitivity index, survival fraction at 2 Gy (SF(2)), was measured by clone formation assay. Telomere length (mean length of telomere restriction fragments, TRF) was examined by Southern blotû telomerase activity (TA) was detected by polymerase chain reaction-based telomeric repeat amplification protocol (PCR-TRAP) coupled with ELISA. RESULTS: After different doses of irradiation, SF(2) of Hep-2 cells was 0.47-0.64; TRF was 3.76-9.43 kb; TA was 1.761-2.606. Each parameter had significant differences among the survival progenies (P<0.05). SF(2) was positively correlated with TRF (r=0.921, P<0.01), and negatively correlated with TA (r=-0.929, P<0.01); TRF was negatively correlated with TA (r=-0.944, P<0.01). CONCLUSION: Radiosensitivity of Hep-2 cells negatively correlates with telomere length, and positively correlates with telomerase activity, which suggest that both telomere length and telomerase activity may be used to predict cellular radiosensitivity.

Carcinoma, Squamous Cell↗

PubMed2005

[Correlation of immunophenotype to cytogenetics and clinical features of adult acute myeloid leukemia].

BACKGROUND & OBJECTIVE: New WHO classification has been rapidly used in diagnosis of leukemia. Based on coexpression and correlation of lineage-associated antigens, multiparameter high-resolution flow cytometry has been developed to precisely identify lineage characteristics of leukemia. Some immunophenotypes correlate with cytogenetic abnormality and prognosis. This study was to analyze immunophenotype of naive acute myeloid leukemia (AML), and explore its correlations to cytogenetics, clinical features, and FAB subtype of AML. METHODS: Multiparameter high-resolution flow cytometry with a panel of 25 different monoclonal antibodies was used to analyze the surface and cytoplasmic antigens expressions of 96 adults with AML; G-binding technique was used to analyze karyotype of 73 of the 96 patients. RESULTS: In these AML patients, some antigens were correlated with FAB subtypes:expression of CD2 was enhanced in AML-M3; HLA-DR, CD34, and CD56 were absent in AML-M3; expression of CD19 was increased in AML-M2; expressions of CD14 and CD56 were enhanced in AML-M5; MPO was absent in AML-M0. Karyotype abnormality was detected in 40(54.8%) patients. CD22, CD56, and TdT expressions were correlated with karyotype abnormality. t(8; 21) was only detected in 10 AML-M2 patients with high expressions of CD15, CD19, CD34, and CD56; no lymphoid lineage antigens were detected in 7 AML-M3 patients with t (15; 17). Expressions of CD4 and TdT were positively correlated with patient's age; expressions of CD7 and CD14 were positively correlated with high white blood cell count; expressions of CD4, CD14, and CD56 were positively correlated with high platelet count. CONCLUSIONS: The abnormal antigen expression of AML is tightly linked with karyotype abnormality. Detection of immunophenotype may help to diagnose and classify AML.

Adolescent↗

PubMedDate not supplied

Non-invasive assessment of arterial stiffness by pulse-wave velocity correlates with endothelial dysfunction.

BACKGROUND: Pulse-wave velocity is the speed of the blood pressure wave to travel a given distance between two sites of the arterial system and is determined by the elasticity, wall thickness and blood density. Pulse-wave velocity correlates well with arterial distensibility and stiffness and is a useful non-invasive index to assess arteriosclerosis. Arterial endothelial dysfunction is one of the key early events in atherogenesis, preceding structural atherosclerotic changes. This study sought to establish the correlation of non-invasive estimation of arterial wall stiffness by pulse-wave velocity and its association with endothelial dysfunction in subjects at higher risk for atherosclerosis. METHODS AND RESULTS: A total of 102 subjects (60 males and 42 females, mean age 51 years), including those with hypertension (n = 39), type 2 diabetes mellitus (n = 26), concomitant type 2 diabetes mellitus and hypertension (n = 29) and primary dyslipidemia without diabetes mellitus and hypertension (n = 8). Pulse-wave velocity was measured by the Vascular Profiler 1000 (VP-1000) waveform analysis and vascular evaluation system, an automated, non-invasive, screening device. Endothelial function was assessed by flow-mediated dilation of the brachial artery. The brachial-artery diameter was measured on B-mode ultrasound images, with the use of a 7.0 MHz linear-array transducer. Mean brachial artery pulse-wave velocity on the right extremity was 1699 cm/s and on the left 1694 cm/s. Mean flow-mediated dilation in the study subjects was 3.6 +/- 8.4%. Mean brachial artery pulse-wave velocity in the right and left extremities and the higher value of brachial artery pulse-wave velocity of the two extremities showed a negative and significant correlation with flow-mediated dilation of the brachial artery (correlation coefficient r = -0.32, p = 0.001; r = -0.40 p < 0.0001; r = -0.37, p = 0.001, respectively). Mean heart-brachial pulse-wave velocity also showed a negative and significant correlation with flow-mediated dilation of the brachial artery (r = -0.23, p = 0.022). Mean arterial stiffness was 36.2 +/- 22%. Arterial stiffness in the right extremity and the higher value of the two extremities showed a negative and significant correlation with flow-mediated dilation of the brachial artery (correlation coefficient r = -0.31, p = 0.002; r = -0.32, p = 0.001, respectively). CONCLUSIONS: Increased values of pulse-wave velocity reflecting upon arterial stiffness show an excellent correlation with reduced values of brachial artery flow-mediated dilation. We propose that the non-invasive modalities of estimation of the pulse-wave velocity and endothelial function estimation by flow-mediated dilation of brachial artery be used in clinical practice in assessment of pre-clinical atherosclerosis.

Aged↗

PubMed2005

Genetic correlations do not constrain the evolution of sexual dimorphism in the moss Ceratodon purpureus.

The trajectory of phenotypic evolution is constrained in the short term by genetic correlations among traits. However, the extent to which genetic correlations impose a lasting constraint is generally unknown. Here, I examine the genetic architecture of life-history variation in male and female gametophytes from two populations of the moss Ceratodon purpureus, focusing on genetic correlations within and between the sexes. A significant negative correlation between allocation to vegetative and reproductive tissue was evident in males of both populations, but not females. All traits showed between-sex correlations of significantly less than one, indicating additive genetic variance for sexual dimorphism. The degree of dimorphism for traits was significantly negatively associated with the strength of the between-sex correlation. The structure of genetic correlations among life-history traits was more divergent between the two populations in females than in males. Collectively, these results suggest that genetic correlations do not impose a lasting constraint on the evolution of life-history variation in the species.

Biological Evolution↗

PubMed2006

Microvessel density: correlation with 18F-FDG uptake and prognostic impact in lung adenocarcinomas.

UNLABELLED: Although researched for many years, the prognostic value of tumor angiogenesis reflected by microvessel density (MVD) is still controversial, and there have been no previous reports regarding the correlation with 18F-FDG uptake in lung adenocarcinomas. Therefore, in the present study, we investigated the correlation between MVD determined with different endothelial cell antibodies and 18F-FDG uptake and compared the prognostic impact of those factors in lung adenocarcinomas. METHODS: Forty-four patients with 45 lung adenocarcinomas underwent 18F-FDG PET before surgery. Consecutive paraffin-embedded sections obtained from each resected tumor were immunostained for CD31 (a panendothelial cell marker), CD105 (a proliferation-related endothelial cell marker), and CD34/alpha-SMA (for double labeling of endothelial cells and mural cells). Four high-power fields in the area with the highest MVD were selected for analysis. Computer-assisted image analysis was used to assess MVD. RESULTS: MVD staining results for panendothelial cell markers can be classified into 3 microvessel patterns: diffuse, alveolar, and mixed. The highly ordered alveolar pattern is believed to represent preexisting alveolar vessels trapped in lung adenocarcinomas and may have no significant meaning for the aggressiveness of tumors. Preexisting alveolar cells also do not contribute to 18F-FDG uptake. CD105 staining of MVD (CD105-MVD) showed a significantly positive correlation with 18F-FDG uptake (P < 0.0001), whereas CD31 staining of MVD (CD31-MVD) showed a marginally negative correlation with it (P = 0.057). Although CD105-MVD correlated negatively with prognosis, patients with low CD105-MVD, compared with those with high or moderate CD105-MVD, had a much better prognosis in both disease-free and overall survival analyses (P = 0.017 and P = 0.013, respectively). Patients with low CD31-MVD had the worst prognosis (P = 0.032 for disease-free survival analysis and P = 0.179 for overall survival analysis). CONCLUSION: There is no positive correlation between 18F-FDG uptake and MVD determined with panendothelial cell markers (CD31 and CD34); in contrast, there is a marginally negative correlation between them. MVD determined with CD105, which is a proliferation-related endothelial cell marker, reflects active angiogenesis, correlates positively with 18F-FDG uptake, and is a better indicator of prognosis in lung adenocarcinomas.

Adenocarcinoma↗