首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献，搜索用时 15 毫秒
1.
The serum PSA is universally accepted as the useful and clinically relevant tumor marker for monitoring therapy and identifying early recurrence in patients of carcinoma prostate throughout the world. However, application of serum PSA is limited to screening for early adenocarcinoma prostate among males above fifty years of age. Serum PSA concentration varies from one population to another in different parts of the world. Many groups of workers have selected 4 ng/ml of serum PSA as upper limit of normal range without giving due consideration for age specific increase in serum PSA. There is no single report available on normal decade wise age specific reference intervals for serum PSA in Indian males. The present study is undertaken to establish age specific reference intervals in healthy Indian males from 20–89 years belonging to subpopulation of Andhra Pradesh from South India. Our results revealed lowest concentration of 95 percentile serum PSA in Indian males compared to other populations globally. Contrary to this, healthy Afro Americans were found to have highest concentration of serum PSA compared to all other populations.  相似文献   

2.
Fifty patients were evaluated for serum total PSA (Prostate Specific Antigen), free PSA (f-PSA), free/total PSA ratio (f/t PSA ratio) and TPSTM (Tissue Polypeptide Specific Antigen). Fifty patients were clinically evaluated and categorized into BPH (benign prostatic hypertrophy) and CaP (carcinoma prostate) with twenty-five in each category before the serological examination. Serum total PSA concentration is elevated in 80% of BPH cases while it was elevated in all cases of CaP. With total PSA>10ng/mL, f/t PSA ratio was not applicable. For TPSTM, a cell proliferation marker these values were 32% and 92% respectively. The advanced cases of CaP were reflected by the pronounced elevations of PSA and TPStM while f/t PSA ratio was much below the cut-off limit (cut-off limit=0.14). The data suggest that whentotal PSA concentration <10ng/mL, f/t PSA ratio plays a very important role in discriminating BPH and CaP. However, TPSTM can be used as a valuable adjunct in diagnosis and follow-up of prostate cancer patients, especially in differentiating benign from malignant cases.  相似文献   

3.
The goal of this study was to determine the stability of Total Prostrate Specific antigen (PSA-T) and Free Prostrate Specific Antigen (PSA-F) in archival serum stored at 4°C and −20°C and subjected to temperature shift due to interruption in power supply. Our study showed that PSA-T was stable up to 285 days and PSA-F was stable for 158 days under these conditions. Since power supply interruption is an unavoidable problem in developing nations, our study has implication on the validity of measurement of PSA-T and PSA-F in serum that was not properly stored due to emergency situations and for certain types of retrospective studies.  相似文献   

4.
Prostate Specific Antigen (PSA) has emerged as the most applicable and important tumor marker for carcinoma prostate. In the present study PSA was determined in serum of healthy subjects, patients of benign prostate hypertrophy (BPH) and Carcinoma Prostate (Ca−P) to evaluate its diagnostic efficiency in day to day management of prostate cancer patients and in differentiating patients of early prostate cancer from those with BPH. Receiver operating characteristic curve (ROC) revealed 2 ng/ml and 10 ng/ml cut off serum PSA level for BPH and untreated carcinoma prostate patients (Ca−P). An extremely significant increase (P<0.0001) was observed in mean PSA concentration in BPH patients and adenocarcinoma prostate patients when compared to healthy males. Clinical relevance of PSA was highlighted by a case study of cancer patient prior to any therapy till death.  相似文献   

5.
This study was conducted to investigate the diagnostic performance characteristics of prostate specific antigen (PSA) by comparing serum PSA value with histological findings in patients suspevted of having prostate cancer in Aminu Kano Teaching Hospital. Nigeria. Clinical and Laboratory records were examined and collated for serum PSA values, together with histological findings of biopsy specimen, clinical diagnosis, age of patients, and mode of presentation. The serum PSA values were determined by ELECSYS 1010 autoanalysers Roche, Germany based on electrochemiluminescence immunoassay technique. The results show that serum PSA values increase with age in the assymptomatic non-cancer patients who came for medical check up but were within normal limit. In prostatic disease conditions PSA values were raised in benign prostatic hyperplasia 35.957± 4.0315ng/ml, in undifferentiated carcinoma 56.22±4.295ng/ml and adenocarcinoma >100ng/ml as compared to the normal range (0–4ng/ml). These cases were confirmed by histological diagnosis. It is concluded that PSA evaluations is a sensitive marker for prostate cancer but because of various other conditions that affect serum PSA concentration, other methods of investigations such as Digital Rectal examination, Trans Urethral Ultra-Sonography and histological examination should be combined to confirm diagnosis. Prognosis of patients will be better if early diagnosis is made.  相似文献   

6.
Prostate specific antigen is considered to be a tumour marker having maximum utility and specificity for prostate cancer since decades. After the discovery of methods to quantify different molecular fractions of prostate specific antigen (PSA), its usefulness in diagnosing early prostate cancer cases has increased tremendously. The “specificity” of PSA, is now challenged by many studies which proved that PSA, once believed to be secreted exclusively by prostatic epithelium, is also present in females. The exact biological role of extraprostatic PSA is still debatable though many theories substantiated by in vitro evidence has been put forward. With the advent of ultrasensitive analytical techniques, PSA is now quantifiable in female serum in its various molecular forms and this has led to many assumptions of it being useful as a marker in female breast cancers. In a similar scenario to prostate cancer, the ratio of free to total PSA is shown to be useful in detecting early breast cancer cases. It is also shown to be a good prognostic indicator and a predictor of response to therapy and recurrence. Apart from its role in breast cancer, it has been advocated to be a marker of hyper androgenic states in women like hirsutism and polycystic ovarian syndrome. Conflicting reports regarding the role of extra prostatic PSA is accumulating but it has been proven beyond doubt that PSA is no longer specific and confined to prostate gland. Various studies have registered that PSA is an ubiquitous molecule, secreted by hormone responsive organs and its synthesis is stimulated by androgens and progesterone but not oestrogens. In this article, a review of various literatures is done about the presence of extra prostatic PSA, its probable role in those sites as well as its utility as a tumour marker in breast cancer.  相似文献   

7.
Prostate carcinoma is the most frequently diagnosed malignancy and the second leading cause of death as a result of cancer in men in the US and other parts of the world. There are conflicting reports on the serum levels of testosterone and 17β-estradiol (E2) in benign prostatic hyperplasia (BPH) and prostate cancer. This study was designed to evaluate the serum concentrations of these hormones in patients with these disorders. Serum levels of prostate specific antigen (PSA), total testosterone and estradiol were determined in 228 subjects comprising of 116 subjects with BPH, 62 subjects with prostate cancer (CaP) and 50 age-matched apparently healthy controls, using ELISA methods. PSA levels were significantly elevated (p < 0.05) in BPH subjects than controls, while there was no significant difference (p > 0.05) in testosterone and estradiol levels of these subjects. PSA and estradiol levels were significantly higher (p < 0.05) in CaP subjects than in controls, while there was no observed significant difference (p > 0.05) in testosterone levels. CaP subjects had significantly raised PSA, testosterone, and estradiol levels than BPH subjects. The mean molar ratio of testosterone: E2 was lowest among CaP patients (134:1) and highest among controls (166:1). Significant positive correlation between PSA and 17β-estradiol was observed in prostate disorders (BPH and CaP patients: r = 0.347; p = 0.000). Significant negative correlations between testosterone and PSA were also observed among BPH patients (r = −0.221, p = 0.049) and control subjects (r = −0.490, p = 0.000). No significant correlation existed between testosterone and PSA in CaP patients (r = 0.051, p = 0.693). Correlations between age and estradiol in both BPH and CaP were not significant (p > 0.05). This study has shown that, there was a significant increase in serum estradiol in CaP subjects, while the testosterone levels in both BPH and CaP subjects were not different from those of controls.  相似文献   

8.
Prostate specific antigen (PSA) has long been used as a biological marker for prostatic cancer. Recent studies have demonstrated that PSA synthesis can be induced by steroid hormones in several tissues of women. Menstrual cycle is regulated by the cyclic variation of estradiol and progesterone. This study was undertaken in order to study the correlation of serum PSA to both these corpus luteal hormones. 110 serum samples and 10 saliva samples were collected from healthy women aged 18–45 years of age having normal menstrual cycles. Active PSA DSL-9700 ultrasensitive kit with detection limit 0.001 ng/ml was used to analyze PSA. 38.2 % of all serum samples and 10 % of saliva samples had detectable concentrations of PSA. The serum PSA was highest during mid follicular phase (between 4th and 8th days of cycle). Variation in PSA levels seemed to follow the variations in progesterone with a lag period of 12–14 days, but did not appear to bear any relationship with the estradiol levels.  相似文献   

9.
The present study deals with the evaluation and comparison of the tumor markers for prostatic carcinoma—The Total Acid Phosphatase (ACP Total) and its Prostatic Fraction (ACP PF) estimated by the enzyme kinetic method, an immunoreactive Prostatic Acid Phosphatase (PAP) and Prostate Specific Antigen (PSA) estimated by enzyme immunoassay. The comparison of all four markers revealed that there was no perfect positive correlation between any of these four markers. PSA had shown a better correlation with ACP Total and its prostatic fraction ACP PF. No correlation was observed between PSA and PAP. Of the four markers PAP exhibited a very low sensitivity, positive and negative predictive values. PSA had shown an absolute specificity, sensitivity, positive and negative predictive values for adenocarcinoma prostate. PSA levels in all phases of disease showed a 100% correlation with disease status. Being a marker with very high tissue specificity and sensitivity, it is revolutionizing the diagnosis of prostatic carcinoma. Hence, it could be used effectively for screening of elderly people over 50 years of age who are at high risk for developing prostatic carcinoma for early diagnosis of this disease.  相似文献   

10.
Recent studies have shown that there are systematic differences among total and free prostate-specificantigen (PSA) immunoassays. In this study we analyzedintermethod differences in total PSA (tPSA) and free PSA(fPSA) measurement using ARCHITECT i2000SR (Abbott Diagnostics) and COBAS E601 (Roche Diagnostics). A number of 160 blood samples were tested for tPSA and 50 samples for fPSA (selecting only sampleswith tPSA: 4.1–10.0 μg/L). Passing–Bablok regression analysis was used to compare the two analytical methods fortPSA, fPSA and percentage of fPSA (%fPSA). A strong correlation was noticed between ARCHITECT i2000SR and COBAS E601 for tPSA, fPSA and %fPSA (r between 0.94 and 0.99). Concentrations of tPSA and fPSA measured by COBAS E601 were higher thanthose measured by ARCHITECT i2000SR with a bias of 0.8 μg/L for tPSA and 0.14 μg/L for fPSA. Analyzing therelative difference between methods for fPSA and %fPSA, COBAS E601 exceed a 10% relative difference limit. Our study confirms that there are differences in measured concentrations of tPSA and fPSA byvarious commercial methods. Because clinical judgment on subsequent diagnostic procedures, such as prostatebiopsy, is based on tPSA and fPSA results, tests harmonization should be a priority.  相似文献   

11.
Now a days measurement of molecular forms of PSA has gained importance in clinical practice. Several studies have demonstrated the production of PSA in female tissues, such as breast. The present piece of work has been undertaken with an objective to estimate the relative proportion of the molecular forms of PSA in serum along with serum testosterone in benign and malignant breast tumor cases and to analyze their association with the severity of the disease process 34 malignant and 26 benign breast disease cases along with 33 healthy controls of same age group were enrolled in this study for evaluation. Serum testosterone was measured by ELISA, whereas serum total PSA (TPSA) and free PSA (FPSA) were estimated by electrochemiluminescence immunoassay. A significant rise of fasting plasma glucose along with prominent dyslipidemia was observed in breast tumor cases. Marked rise in serum testosterone as well as TPSA and FPSA was documented in both benign and malignant breast tumor cases. Serum testosterone revealed a significant positive association with both TPSA and FPSA pointing towards an etiological association between them. However, surgical removal of tumor mass resulted in a marked decline of presurgical value of both TPSA and FPSA with a non-significant fall in serum testosterone revealing tumor tissue as the source of FPSA and TPSA. Thus, estimation of PSA provides prognostic information that may assist in future treatment.  相似文献   

12.
Approaches to the stabilization of tumor markers vary depending on the lability of the tumor marker. Thus while merely freezing the serum promptly at ?70°C may be adequate for some analytes such as gastrin, some other polypeptide hormones such as vasoactive intestinal peptide require collection of blood in EDTA and prompt freezing of plasma to protect the analyte from metal oxidation. In addition to collection of blood in EDTA an addition of a proteolytic enzyme inhibitor such as aprotinin may be necessary to preserve labile polypeptide hormones such as ACTH, somatostatin etc. Analytes such as parathyroid hormone related protein (PTH-rp) are so labile that additives such as leupeptin and pepstatin have to be added to EDTA and aprotinin and the plasma refrigerated to achieve stability for up to 24 hrs. Catecholamines also require stabilization with additives such as EGTA and glutathione and prompt freezing of plasma at ?70°C. Special precautions are required in handling tumor tissue intended for hormone receptor measurements since they are not only extremely heat labile but are also subjected to alteration during specimen preparation.  相似文献   

13.
Recent studies have demonstrated the presence of prostate specific antigen (PSA) in cord blood of male as well as female babies. The placental progesterone and estradiol up-regulate the synthesis and secretion of PSA in Placenta. This PSA is presumed to play a role in intrauterine growth of fetus by virtue of its proteolytic action on several substrates including insulin-like-growth-factor-binding-protein-3, insulin chains and Interleukin-2. This study was planned with the objective of correlating the levels of PSA in cord blood to gestation at delivery, the type of delivery and gender of the fetus. Fifty-seven cord blood samples were collected from the umbilical cord during delivery or mid-trimester abortion and analyzed for PSA using ‘Active PSA DSL-9700 ultra sensitive’ kit employing two-site immuno-radiometric assay principle and having a detection limit of 0.001 ng/ml. Mean PSA levels in cord blood were found to be 0.112 ± 0.027 ng/ml. The concentration of PSA in cord blood was found to be higher in case of higher gestational age, male baby and operative delivery. 50 % of cord bloods for female babies had PSA below detection limit (range <0.001–0.460 ng/ml), while all the male samples had detectable PSA (range 0.11–0.973 ng/ml). Higher Progesterone levels found in prenatal maternal blood in case of male babies may be responsible for the higher cord blood PSA. Mean cord blood PSA was 0.150 ± 0.150 ng/ml in forceps delivery and 0.078 ± 0.012 ng/ml in normal vaginal delivery. Forceps delivery causes much more stress and strain as compared to a normal vaginal delivery, resulting in increased levels of adrenal glucocorticoids, and therefore, higher cord blood PSA.  相似文献   

14.
IntroductionIt is common for patients to switch between several healthcare providers. In this context, the long-term follow-up of medical conditions based on laboratory test results obtained from different laboratories is a challenge. The measurement uncertainty in an inter-laboratory context should also be considered in data mining research based on routine results from randomly selected laboratories. As a proof-of-concept study, we aimed at estimating the inter-laboratory reference change value (IL-RCV) for exemplary analytes from publicly available data on external quality assessment (EQA) and biological variation.Materials and methodsExternal quality assessment data of the Reference Institute for Bioanalytics (RfB, Bonn, Germany) for serum creatinine, calcium, aldosterone, PSA, and of whole blood HbA1c from campaigns sent out in 2019 were analysed. The median CVs of all EQA participants were calculated based on 8 samples from 4 EQA campaigns per analyte. Using intra-individual biological variation data from the EFLM database, positive and negative IL-RCV were estimated with a formula based on log transformation under the assumption that the analytes under examination have a skewed distribution.ResultsWe estimated IL-RCVs for all exemplary analytes, ranging from 13.3% to 203% for the positive IL-RCV and - 11.8% to - 67.0% for the negative IL-RCV (serum calcium - serum aldosterone), respectively.ConclusionExternal quality assessment data together with data on the biological variation – both freely available – allow the estimation of inter-laboratory RCVs. These differ substantially between different analytes and can help to assess the boundaries of interoperability in laboratory medicine.  相似文献   

15.

Introduction

The collected and shipped blood samples are exposed to a various extra-analytical factors prior to analysis. The aim of the study was to determine the stability of analytes in serum gel tubes and plain tubes exposed to a range of storage temperatures and times after centrifugation.

Materials and methods:

Fifteen healthy volunteers were recruited and venous blood was collected into four tubes, two with and two without gel separator. Analyzing the baseline samples in 30 min, all were stored at 4ºC or 24ºC for 6, 12, 18, 24, 30, 36, 48 and 72 hours and 1 week. Sixteen biochemical anaytes were measured on each sample. Variations remained under the desirable bias considered as clinically insignificant.

Results:

On day three, most analytes remained stable including albumin, protein, creatinine, cholesterol, triglycerides, gamma-glutamyl transferase (GGT), alkaline phosphatase (ALP), alanine aminotransferase (ALT), creatine kinase (CK), lactate dehydrogenase (LD) regardless of tube types. Glucose concentration decreased markedly (P = 0.001) beginning from the first hours of storage in plain serum. The stability maximized for the analytes including glucose, total bilirubin, urea nitrogen (BUN), uric acid stored at 4 ºC in gel tubes. Aspartate aminotransferase (AST) activity increased significantly (P = 0.002) up to 48-h, however bias was not significant clinically. High density lipoprotein (HDL) concentration was stable in gel tubes at 24 ºC, in plain tubes at 4 ºC stored up to 36-h.

Conclusion:

Serum gel or non-gel tubes might be used interchangeably for 11 analytes chilled or at 24 ºC, whereas some restrictions must be applied for glucose, AST, BUN, HDL, and uric acid.  相似文献   

16.
A 50 year old male was admitted in our hospital with anemia and impaired renal function. He was subsequently found to have extremely elevated serum phosphate level (24 mg/dL, reference interval: 2.5–4.5 mg/dL) with normal serum calcium when assayed on a Beckman Coulter AU 480® analyser. Clinico-biochemical discrepancy led to the suspicion of spurious hyperphosphatemia. Serum total protein was grossly elevated with gross reversal of albumin to globulin ratio. Serum electrophoresis revealed a large M band and was confirmed as Ig G-Kappa type on immunofixation. Subsequently a bone marrow aspiration biopsy confirmed the diagnosis of multiple myeloma. The patient serum was then reassayed for phosphate on a Vitros® 250 Dry Chemistry platform and the result was within normal reference interval. Paraproteinemias are a common cause of analytical interference in clinical biochemistry laboratories and as multilayered film technology platforms like Vitros® assay most routine analytes on a protein free filtrate they are unaffected by paraprotein interference. Clinically discordant patient results should always be interpreted keeping such interferences in mind.  相似文献   

17.

Introduction:

Optimal storage of serum specimens in central laboratories for a long period for multicenter reference interval studies, or epidemiologic studies remains to be determined. We aimed to examine the analytical stability of chemistry analytes following numerous freeze-thaw and long term storage.

Materials and methods:

Serum samples were obtained from 15 patients. Following baseline measurement, sera of each subject were aliquoted and stored at −20 °C for two experiments. A group of sera were kept frozen for up to 1, 2 and 3 months and then analyzed for stability. The other experiment consisted of one to ten times of freeze and thaw cycles. Total of 17 chemistry analytes were assayed at each time point. The results were compared with those obtained from the initial analysis of fresh samples. Median or mean changes from baseline (T0) concentrations were evaluated both statistically and clinically according to the desirable bias.

Results:

Of the analytes studied, aspartate aminotransferase (AST), alanine aminotransferase (ALT), creatine kinase (CK), gamma-glutamyl transferase (GGT), direct bilirubin, glucose, creatinine, cholesterol, triglycerides, high density lipoprotein (HDL) were stable in all conditions. Blood urea nitrogen (BUN), uric acid, total protein, albumin, total bilirubin, calcium, lactate dehydrogenase (LD) were changed significantly (P < 0.005).

Conclusions:

As a result, common clinical chemistry analytes, with considering the variability of unstable analytes, showed adequote stability after 3 months of storage in sera at −20 °C, or up to ten times of freeze-thaw cycle. All the same, such analysis can only be performed for exceptional cases, and this should be taken into account while planning studies.  相似文献   

18.
The study was aimed at presence of specific IgE antibody levelsinvitro to the identified antigen. Based on positive skin test with Gynandropsis gynandra and elevated levels of total IgE (>325 IU/ml) 104 patients were selected. Healthy, asymptomatic individuals (25) with low total IgE (<325 IU/ml) were included as controls. The mean OD values by ELISA for specific IgE were 0.67±0.21, 0.57±0.18 and 0.56±0.18 with whole pollen antigen, 46-37 kD fraction and 36-32 kD fraction, respectively. The specificity and sensitivity between skin test positivity with whole pollen antigen verses fraction with mol.wt 46-37 kD was 90% and 90% and for fraction with mol.wt 36-32 kD was found to be 81.1% and 89.4%. The clusters with molecular weights 46-37 kD and 36-32 kD may be useful inin vitro diagnostic test. Fractions within these clusters need to be identified for a higher specificity.  相似文献   

19.
The thyroid hormone profile of a hypothyroid patient, with moderate sized diffuse goiter and history of exogenous thyroid hormone therapy, was found to be highly ambiguous. The total as well as free T4 levels were consistently high (out of range) with suppressed T3 (total and free) and elevated thyrotropin levels. We incubated the serum with the radio-iodine labelled T4 and observed that the patient’s serum bound about 50.5% of the total radioactivity resulting in 85.3% interference in the radioimmunoassay. On resolving the serum proteins by cellulose acetate electrophoresis, the radioactivity was detected in the gamma globulin band. The protein profile showed mildly raised levels of IgG. Therefore it was established that the patient’s serum carried T4 reactive antibodies (IgG) which were interfering in the immunoassays. Elevated anti-thyroid microsomal antibodies were also present in the patient’s serum. The anti-T4 antibodies were highly specific for T4 and did not show any cross reactivity with the T3 or its analogues used in the estimation of free T3. We stripped the serum by precipitating the immunoglobulins and were successful in estimating the levels of free T4 in the stripped serum by single step radioimmunoassy.  相似文献   

20.
Sigma is a metric that quantifies the performance of a process as a rate of Defects-Per-Million opportunities. In clinical laboratories, sigma metric analysis is used to assess the performance of laboratory process system. Sigma metric is also used as a quality management strategy for a laboratory process to improve the quality by addressing the errors after identification. The aim of this study is to evaluate the errors in quality control of analytical phase of laboratory system by sigma metric. For this purpose sigma metric analysis was done for analytes using the internal and external quality control as quality indicators. Results of sigma metric analysis were used to identify the gaps and need for modification in the strategy of laboratory quality control procedure. Sigma metric was calculated for quality control program of ten clinical chemistry analytes including glucose, chloride, cholesterol, triglyceride, HDL, albumin, direct bilirubin, total bilirubin, protein and creatinine, at two control levels. To calculate the sigma metric imprecision and bias was calculated with internal and external quality control data, respectively. The minimum acceptable performance was considered as 3 sigma. Westgard sigma rules were applied to customize the quality control procedure. Sigma level was found acceptable (≥3) for glucose (L2), cholesterol, triglyceride, HDL, direct bilirubin and creatinine at both levels of control. For rest of the analytes sigma metric was found <3. The lowest value for sigma was found for chloride (1.1) at L2. The highest value of sigma was found for creatinine (10.1) at L3. HDL was found with the highest sigma values at both control levels (8.8 and 8.0 at L2 and L3, respectively). We conclude that analytes with the sigma value <3 are required strict monitoring and modification in quality control procedure. In this study application of sigma rules provided us the practical solution for improved and focused design of QC procedure.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号