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R A Quintero - One of the best experts on this subject based on the ideXlab platform.
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appraisal of the Selectivity Index in a cohort of patients treated with laser surgery for twin twin transfusion syndrome
American Journal of Obstetrics and Gynecology, 2010Co-Authors: Luminita Crisan, Eftichia V Kontopoulos, R A QuinteroAbstract:Objective The Selectivity Index (SI) has been proposed as a measure of technical success in laser surgery for twin–twin transfusion syndrome. Surgeries with an Index >–0.25 have been considered highly selective. The purpose of this study was to evaluate the applicability of this Index in our patient population. Study Design The SI was assessed in 314 consecutive laser surgeries and correlated with perinatal survival. Results A total of 310 patients (98.7%) underwent a completely selective procedure. The SI was 0.8 in the selective laser photocoagulation of communicating vessels group vs 0.3 in the nonselective laser photocoagulation of communicating vessels group ( P = .001). In the selective group perinatal survival of at least 1 twin (92.6% vs 50%) and survival of the donor (75.4% vs 0%) was significantly better ( P = .05). Conclusion The SI as originally proposed is misleading and of limited use as it does not differentiate selective from nonselective procedures. We propose instead using a ratio of selective/nonselective procedures, and selectively coagulated/total number of coagulated vessels to appraise center-specific and patient-specific surgical performance of laser surgery for twin–twin transfusion syndrome.
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Appraisal of the Selectivity Index in a cohort of patients treated with laser surgery for twin-twin transfusion syndrome.
American journal of obstetrics and gynecology, 2009Co-Authors: Luminita Crisan, Eftichia V Kontopoulos, R A QuinteroAbstract:The Selectivity Index (SI) has been proposed as a measure of technical success in laser surgery for twin-twin transfusion syndrome. Surgeries with an Index >-0.25 have been considered highly selective. The purpose of this study was to evaluate the applicability of this Index in our patient population. The SI was assessed in 314 consecutive laser surgeries and correlated with perinatal survival. A total of 310 patients (98.7%) underwent a completely selective procedure. The SI was 0.8 in the selective laser photocoagulation of communicating vessels group vs 0.3 in the nonselective laser photocoagulation of communicating vessels group (P = .001). In the selective group perinatal survival of at least 1 twin (92.6% vs 50%) and survival of the donor (75.4% vs 0%) was significantly better (P = .05). The SI as originally proposed is misleading and of limited use as it does not differentiate selective from nonselective procedures. We propose instead using a ratio of selective/nonselective procedures, and selectively coagulated/total number of coagulated vessels to appraise center-specific and patient-specific surgical performance of laser surgery for twin-twin transfusion syndrome. Copyright 2010 Mosby, Inc. All rights reserved.
Atsushi Yamauchi - One of the best experts on this subject based on the ideXlab platform.
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New Selectivity Index calculated using protein fraction as a substitute for the conventional Selectivity Index
Clinical and Experimental Nephrology, 2019Co-Authors: Jun Nakamura, SATOSHI MASUYAMA, Katsuyuki Nagatoya, Naohiko Fujii, Aki Warada, Atsuyuki Tokuyama, Sachio Kajimoto, Ryota Haga, Atsushi YamauchiAbstract:BackgroundSelectivity Index (SI) of proteinuria, calculated using the clearance ratio of immunoglobulin G to transferrin, predicts the response to glucocorticoids in patients with nephrotic syndrome. However, there is disagreement regarding the suitability of SI. Therefore, alternate indices should be considered. This study investigated whether or not Selectivity Index protein fraction (SIPF) was inferior to SI for the prediction of the response to glucocorticoids.MethodsForty-nine patients with nephrotic syndrome were evaluated. On the basis of molecular weight and protein fraction, as an inexpensive substitute for SI, the clearance ratio of the albumin to γ fractions measured in serum and urine protein fractions was defined as SIPF. The quality of SIPF was examined. Moreover, the best cutoff value of SIPF was determined; and SIPF distribution, according to histopathological diagnosis by renal biopsy, was examined.ResultsSIPF was strongly correlated with SI ( r = 0.79, P 0.45, only two patients with minimal change disease (MCD) achieved complete remission. In the group with SIPF ≤ 0.45, all patients with MCD achieved complete remission, although eight patients with other histopathological diagnoses did not achieve complete remission.ConclusionsAnalysis of protein fractions as a substitute for SI may be useful for predicting response to glucocorticoids in patients with nephrotic syndrome.
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new Selectivity Index calculated using protein fraction as a substitute for the conventional Selectivity Index
Clinical and Experimental Nephrology, 2019Co-Authors: Jun Nakamura, SATOSHI MASUYAMA, Katsuyuki Nagatoya, Naohiko Fujii, Aki Warada, Atsuyuki Tokuyama, Sachio Kajimoto, Ryota Haga, Atsushi YamauchiAbstract:Selectivity Index (SI) of proteinuria, calculated using the clearance ratio of immunoglobulin G to transferrin, predicts the response to glucocorticoids in patients with nephrotic syndrome. However, there is disagreement regarding the suitability of SI. Therefore, alternate indices should be considered. This study investigated whether or not Selectivity Index protein fraction (SIPF) was inferior to SI for the prediction of the response to glucocorticoids. Forty-nine patients with nephrotic syndrome were evaluated. On the basis of molecular weight and protein fraction, as an inexpensive substitute for SI, the clearance ratio of the albumin to γ fractions measured in serum and urine protein fractions was defined as SIPF. The quality of SIPF was examined. Moreover, the best cutoff value of SIPF was determined; and SIPF distribution, according to histopathological diagnosis by renal biopsy, was examined. SIPF was strongly correlated with SI (r = 0.79, P 0.45, only two patients with minimal change disease (MCD) achieved complete remission. In the group with SIPF ≤ 0.45, all patients with MCD achieved complete remission, although eight patients with other histopathological diagnoses did not achieve complete remission. Analysis of protein fractions as a substitute for SI may be useful for predicting response to glucocorticoids in patients with nephrotic syndrome.
J Tencer - One of the best experts on this subject based on the ideXlab platform.
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Diagnostic and prognostic significance of proteinuria Selectivity Index in glomerular diseases.
Clinica chimica acta; international journal of clinical chemistry, 2020Co-Authors: J Tencer, O Bakoush, O TorffvitAbstract:The proteinuria Selectivity Index (SI) describes changes of the glomerular permeability for macromolecules. In the present study, we examine the implications of SI as a diagnostic (199 patients) and a prognostic (49 patients) marker in glomerular diseases. Using SI based on alpha(2)-macroglobulin (alpha(2)-M-SI) or on IgM (IgM-SI) we found that minimal change nephropathy could be discriminated by low SI values and crescentic necrotizing glomerulonephritis by high SI values compared to other diseases. SI based on IgG (IgG-SI) was less useful in determining specific diagnoses. During a follow-up of 46 months creatinine clearance (Cr cl) decreased 36% in a group of patients with high IgG-SI (>0.2) and 38% in a group of patients with high IgM-SI (>1.5(-3)) compared to only 8% in patients with low IgG-SI (
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High proteinuria Selectivity Index based upon IgM is a strong predictor of poor renal survival in glomerular diseases
Nephrology Dialysis Transplantation, 2001Co-Authors: O Bakoush, O Torffvit, Bengt Rippe, J TencerAbstract:BACKGROUND: The transport of large proteins across the glomerular capillary wall (GCW) may increase several fold in glomerular diseases. The occurrence of IgM in urine is a consequence of the presence of large defects or shunts in the GCW, whereas albuminuria is probably a result of an altered charge- and size-Selectivity of the GCW. In order to examine whether patho-morphological differences influence the renal outcome in proteinuric glomerulopathies, we examined urinary excretion of IgM and albumin as prognostic markers of glomerular disease. METHODS: An observational study over a median of 41 (+/-3) months was conducted in 84 patients with biopsy-verified glomerular disease. The patients were subdivided into groups with low ( 0.002) proteinuria Selectivity Index based upon IgM (IgM-SI), and into groups with low ( 200 mg/mmol) albumin creatinine Index (ACI). RESULTS: In the high IgM-SI group, the median creatinine clearance (Ccr) decreased by 26%, and 62% of the patients decreased in Ccr by >5 ml/ min/year during the follow-up time. In comparison, the median Ccr decreased by 8% in the low IgM-SI group (P 5 ml/min/year in the Ccr. Eleven (21%) of the 51 patients in the high IgM-SI group developed end-stage renal failure compared with none of the 33 patients in the low IgM-SI group. All the patients that progressed to uraemia had decreased Ccr (
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high proteinuria Selectivity Index based upon igm is a strong predictor of poor renal survival in glomerular diseases
Nephrology Dialysis Transplantation, 2001Co-Authors: O Bakoush, O Torffvit, Bengt Rippe, J TencerAbstract:BACKGROUND: The transport of large proteins across the glomerular capillary wall (GCW) may increase several fold in glomerular diseases. The occurrence of IgM in urine is a consequence of the presence of large defects or shunts in the GCW, whereas albuminuria is probably a result of an altered charge- and size-Selectivity of the GCW. In order to examine whether patho-morphological differences influence the renal outcome in proteinuric glomerulopathies, we examined urinary excretion of IgM and albumin as prognostic markers of glomerular disease. METHODS: An observational study over a median of 41 (+/-3) months was conducted in 84 patients with biopsy-verified glomerular disease. The patients were subdivided into groups with low ( 0.002) proteinuria Selectivity Index based upon IgM (IgM-SI), and into groups with low ( 200 mg/mmol) albumin creatinine Index (ACI). RESULTS: In the high IgM-SI group, the median creatinine clearance (Ccr) decreased by 26%, and 62% of the patients decreased in Ccr by >5 ml/ min/year during the follow-up time. In comparison, the median Ccr decreased by 8% in the low IgM-SI group (P 5 ml/min/year in the Ccr. Eleven (21%) of the 51 patients in the high IgM-SI group developed end-stage renal failure compared with none of the 33 patients in the low IgM-SI group. All the patients that progressed to uraemia had decreased Ccr (<60 ml/min) at entry into the study. However, among all these patients, only those with high IgM-SI, and none with low IgM-SI, developed end stage renal failure. The fall in Ccr did not differ significantly between the patients in high (12%) and low (16%) ACI groups. CONCLUSION: The results of this study indicate that an increased IgM-SI value is a stronger predictor of clinical outcome in proteinuric glomerulopathies than baseline albuminuria. This finding may reflect different patho-histological mechanisms influencing renal survival in glomerular diseases.
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diagnostic and prognostic significance of proteinuria Selectivity Index in glomerular diseases
Clinica Chimica Acta, 2000Co-Authors: J Tencer, O Bakoush, O TorffvitAbstract:The proteinuria Selectivity Index (SI) describes changes of the glomerular permeability for macromolecules. In the present study, we examine the implications of SI as a diagnostic (199 patients) and a prognostic (49 patients) marker in glomerular diseases. Using SI based on alpha(2)-macroglobulin (alpha(2)-M-SI) or on IgM (IgM-SI) we found that minimal change nephropathy could be discriminated by low SI values and crescentic necrotizing glomerulonephritis by high SI values compared to other diseases. SI based on IgG (IgG-SI) was less useful in determining specific diagnoses. During a follow-up of 46 months creatinine clearance (Cr cl) decreased 36% in a group of patients with high IgG-SI (>0.2) and 38% in a group of patients with high IgM-SI (>1.5(-3)) compared to only 8% in patients with low IgG-SI (Indexes. The decline rate of Cr cl correlated significantly to the SI levels but not to the degree of albuminuria. The findings of the study indicate that urinary excretion of high-molecular-weight proteins, and not of albumin, is a potential prognostic marker in proteinuric glomerulopathies and it may also serve as valuable diagnostic aid in these disorders. (Less)
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proteinuria Selectivity Index based upon α2 macroglobulin or igm is superior to the igg based Index in differentiating glomerular diseases technical note
Kidney International, 1998Co-Authors: J Tencer, O Torffvit, Hans Thysell, Bengt Rippe, Anders GrubbAbstract:Proteinuria Selectivity Index based upon α 2 -macroglobulin or IgM is superior to the IgG based Index in differentiating glomerular diseases. Technical Note. Background The proteinuria Selectivity Index (SI) may be used to describe changes of the glomerular permeability for macromolecules in glomerular diseases. Proteins the size of α 2 -macroglobulin (α 2 M) or IgM cannot normally pass the glomerular barrier, whereas IgG can pass through the large pores of glomerular basement membrane. Comparison of the clearance of the three high-molecular-weight proteins to that of albumin may be useful in characterization and diagnosis of different glomerular diseases as well as in understanding of the permeability characteristics of the glomerular filter. Methods Three types of SI, each calculated as a ratio of clearance of either IgG, α 2 M or IgM to that of albumin, were measured in 199 proteinuric patients. The patients were subdivided into eight different biopsy-verified glomerular diseases. Results Two diagnoses could be clearly distinguished using SI based on α 2 M (α 2 M SI) or IgM (IgM SI). Both α 2 M SI and IgM SI were significantly lower in minimal change nephropathy and higher in crescentic necrotizing glomerulonephritis than in all the other diagnoses. The SI based on IgG (IgG SI) was less useful in determining specific diagnoses, since patients with minimal change nephropathy could not be distinguished from those with other types of primary glomerulonephritis and patients with crescentic necrotizing glomerulonephritis did not differ from those with diabetic nephropathy. Conclusions The findings of this study indicate that α 2 M SI and IgM SI are superior to IgG SI in characterization of glomerular disorders and might replace the IgG SI for this purpose.
Luminita Crisan - One of the best experts on this subject based on the ideXlab platform.
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appraisal of the Selectivity Index in a cohort of patients treated with laser surgery for twin twin transfusion syndrome
American Journal of Obstetrics and Gynecology, 2010Co-Authors: Luminita Crisan, Eftichia V Kontopoulos, R A QuinteroAbstract:Objective The Selectivity Index (SI) has been proposed as a measure of technical success in laser surgery for twin–twin transfusion syndrome. Surgeries with an Index >–0.25 have been considered highly selective. The purpose of this study was to evaluate the applicability of this Index in our patient population. Study Design The SI was assessed in 314 consecutive laser surgeries and correlated with perinatal survival. Results A total of 310 patients (98.7%) underwent a completely selective procedure. The SI was 0.8 in the selective laser photocoagulation of communicating vessels group vs 0.3 in the nonselective laser photocoagulation of communicating vessels group ( P = .001). In the selective group perinatal survival of at least 1 twin (92.6% vs 50%) and survival of the donor (75.4% vs 0%) was significantly better ( P = .05). Conclusion The SI as originally proposed is misleading and of limited use as it does not differentiate selective from nonselective procedures. We propose instead using a ratio of selective/nonselective procedures, and selectively coagulated/total number of coagulated vessels to appraise center-specific and patient-specific surgical performance of laser surgery for twin–twin transfusion syndrome.
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Appraisal of the Selectivity Index in a cohort of patients treated with laser surgery for twin-twin transfusion syndrome.
American journal of obstetrics and gynecology, 2009Co-Authors: Luminita Crisan, Eftichia V Kontopoulos, R A QuinteroAbstract:The Selectivity Index (SI) has been proposed as a measure of technical success in laser surgery for twin-twin transfusion syndrome. Surgeries with an Index >-0.25 have been considered highly selective. The purpose of this study was to evaluate the applicability of this Index in our patient population. The SI was assessed in 314 consecutive laser surgeries and correlated with perinatal survival. A total of 310 patients (98.7%) underwent a completely selective procedure. The SI was 0.8 in the selective laser photocoagulation of communicating vessels group vs 0.3 in the nonselective laser photocoagulation of communicating vessels group (P = .001). In the selective group perinatal survival of at least 1 twin (92.6% vs 50%) and survival of the donor (75.4% vs 0%) was significantly better (P = .05). The SI as originally proposed is misleading and of limited use as it does not differentiate selective from nonselective procedures. We propose instead using a ratio of selective/nonselective procedures, and selectively coagulated/total number of coagulated vessels to appraise center-specific and patient-specific surgical performance of laser surgery for twin-twin transfusion syndrome. Copyright 2010 Mosby, Inc. All rights reserved.
Igor Kissin - One of the best experts on this subject based on the ideXlab platform.
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an early indicator of drug success top journal Selectivity Index
Drug Design Development and Therapy, 2013Co-Authors: Igor KissinAbstract:The Top Journal Selectivity Index (TJSI) is a scientometric Index reflecting the potential importance of a new drug. It represents the ratio of the number of all types of articles on a particular drug in the top 20 journals relative to the number of articles in all (>5,000) biomedical journals covered by Medline over the 5 years since the drug’s introduction. The TJSI can be an indicator of a drug’s potential for sustained use: a higher score increases the probability of continuing success.
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top journals Selectivity Index and me too drugs
Scientometrics, 2012Co-Authors: Igor Kissin, Edwin L BradleyAbstract:To assess the probability of success of an analgesic drug we have proposed a bibliometric indicator, the Top Journals Selectivity Index (TJSI) (Kissin 2011). It represents the ratio (as %) between the number of all types of articles on a particular drug in the top 20 biomedical journals and the number of articles on that drug in all (>5,000) journals covered by Medline over the first 5 years after that drug's introduction. The aim of this study was to demonstrate that TJSI may be used for the assessment of follow-on drugs (those that follow a first-in-class drug). The study tested two hypotheses. First, TJSI can detect the difference (in the same class) between drugs with distinguishing features and drugs without them ("me-too" drugs) better than other publication indices, i.e., the number of all types of articles on a drug in journals presented by Medline (AJI), and the number of articles covering only randomized controlled trials (RCT). Second, there is a relationship between the TJSI of "me-too" drugs and the order (sequential number) in which those drugs reached the market. The study was based on drug classes approved for marketing between the 1960's and the early 2000's. The eight classes that had 4 or more drugs were included for analysis. Five specific indicators were used to determine drug's distinguishing pharmacological properties. It was found that TJSI can detect the difference between follow-on drugs with distinguishing features and those without them better than the other publication indices (AJI or RCT). Our analysis also demonstrated a negative correlation (r = ?0.372, p = 0.014) between the TJSI of drugs without distinguishing features ("me-too" drugs) and the order of the drug's market entry. This implies that TJSI could be useful for the assessment of situations with multiple market entrants in the same class when a new addition has a questionable value.
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top journals Selectivity Index is it acceptable for drugs beyond the field of analgesia
Scientometrics, 2011Co-Authors: Igor Kissin, Edwin L BradleyAbstract:To predict the success of an analgesic drug we have suggested a bibliometric indicator, the Top Journals Selectivity Index (TJSI) (Kissin, Scientometrics, 86:785---795, 2011). It represents the ratio (as %) between the number of all types of articles on a particular drug in the top 20 biomedical journals and the number of articles on that drug in all (>5,000) journals covered by Medline over the first 5 years after a drug's introduction. For example, the highest TJSI score among analgesics was that of sumatriptan, the most successful drug for the treatment of migraine. The aim of this study was to demonstrate that TJSI may be used not only in the field of analgesics, but also for various other categories of drugs. The study tested two hypotheses. First, the difference between the most successful and less successful drugs in any pharmacological class can be reliably detected by TJSI. Second, drugs with TJSI indicators as high as that of sumatriptan can be found among other pharmacological classes as well. Drugs from various pharmacological classes approved by the Federal Drug Administration (FDA) during the 10-year period, 1980---1989, were used in this study. Two groups of 10 drugs were selected to test the first hypothesis. One group included the most successful (breakthrough) drugs; the other included less successful drugs matched with the breakthrough drugs according to mechanism of action. The difference between the two groups was compared using three publication indices: the TJSI, the number of all types of articles on a drug in journals presented by Medline (AJI), and the number of articles covering only randomized controlled trials (RCT). It was found that TJSI can detect the difference between the two groups of drugs better than the two other indices. TJSI detected the difference between a breakthrough drug and its less successful counterpart at least 69% of the time with 95% confidence. With the other two indices the difference was not distinguishable from random chance. Some of the breakthrough drugs (zidovudine, omeprazole, lovastatin) have TSJIs as high or even higher than that of sumatriptan (19.2 vs. 23.0, 21.4, and 20.6, respectively). In conclusion, TJSI can be useful not only in the field of analgesics, but also with drugs belonging to other pharmacological classes.
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Can a bibliometric indicator predict the success of an analgesic
Scientometrics, 2010Co-Authors: Igor KissinAbstract:In the assessment of success of new analgesic drugs over the past 50 years (Kissin, Anesth Analg 110:780---789, 2010) we observed a difference in the publication response to a new drug between biomedical journals in general and top journals: number of published articles on a drug increased (and declined) more rapidly in the top journals. Based on this phenomenon we present a new publication indicator--the Top Journal Selectivity Index (TJSI). It represents the ratio between the number of all types of articles in the top 20 biomedical journals and the number of articles in all (>5,000) journals covered by Medline, over 5 years after a drug's introduction. Ten analgesics developed during the period 1986---2009 were selected for analysis. Three publication indices were used for assessment: the number of all types of articles presented in Medline, the number of articles covering only randomized controlled trials (RCT), and the Top Journal Selectivity Index. We also assessed the success score in the development of these analgesics based on the following criteria: novelty of molecular target, analgesic efficacy, and response by the pharmaceutical market. The relationships between the publication indices and analgesic's success score were determined with the use of the Pearson correlation coefficient. Positive relationship was found only with the Top Journal Selectivity Index (r = 0.876, p < 0.001). We suggest that this Index can predict success in drug development at least in the field of analgesics.
