- Email: [email protected]
Detection of fibronectin fragments in urine samples from diabetics
POSTER ABSTRACTS Reml~ At a cut-off of 20 mg/L, the Ivfioral-Testshowed a poor senmtivity (56%). Correction for creafininc did incresee the sensitivity (69%) for the same specificity (98.7"A). The beat screening performance was obtained when the I~emI-Te=t results were expressed as rate 0tg/min) with a recciver-o~ttor characteristic (ROC) curve area of 0.96. Conclusion Semi-qusatitativ,; determination of mieroalbuminuda on an ovemi#t tpecimen shows an inadequate sensitivity unless it is comoted for udue conecntrstion (ereetinine). A better serecning performance is obtained by using a timed specimen and calculatinn of micrcalbumin excretion rote.
taiued betwesa fruetmamiue sad mean #umse for the preceding twe or three weeks (r - 0.45). The vadaeon in mean 81ueose levels was high, in some imtances 8renter than 50",4 of the mean. For any individual palicnt, elumSesin fmctoeamine were minimal and did not always ~qate to mean blnod sugar. The mean 81ueme levels computed for the a i ~ - ~ ate time intervals showed • better correlation with HbAIo levels (r 0.73). Con¢iuaion The poor correlation between the mean glucose and fmctoeamine makes it dilfieult to infer the average glycemin in the pre. ceding two to three weeks and did not add to the decision-making for
managementof the patients. 16
COMPARAgSON OF IMMUNOTURBIDIMgTRIC AND FPLC METHODS FOR THE MEASUREMENT OF
18
GLYCATED H E M O G L O B I N A1¢ (HbAlc) Benin A.. Ocoffroy, L., and Dclvin, E.E., Depts of Clinical Biochemistry and Pediatri,~, Hopital Ste-Justino, Montreal, Quebec, H3T IC5, Canada Olycated HbAI e is sccoptod as an independent variable of long glyuemin control in diabetic I~den~ The DCA 2000 Odiics Canada) is an instrument wish allows a rapid i m m ~ e t r i c micrcassay. It is based on antibody specificity for the gucoas Amadori condensation product with the first three aminmekh located at the NH2-terminal end of the hemnginbin I~hain. Objecgve~ We have compared the DCA 2000 to the classicalFPLC method in terw of reproducibility, i:euracy and clinical impact. Megmds DCA 2000 and FPLC measurements were both performed on the same 72 blood samples collected at the time of the follow-up diabetes clinics. P~mdta A correlation study shows an execllent agreement between the two methods. Regression analysis gives the following equation: DCA 2000-1.063FPI~+0.003(rt-0.98). Intra- and inter-assay coefl'~eiontof variations (n-20) are 0.96 attd 2.20% respectively. The slight bias ohserved has no ulinical relevance. Variant hemoglobin content of some sample, has al~arently no efli~ on the measurement done with the DCA 2000. Results could be returned to the physician within 15 rain. after ssmple reception. Condm/on The DCA 2000 is a rapid, sensitive sad reliable method for the measurement of HbAle. It is amenable to be used in sites remote from rite central laboratory.
Eiim. e.g.. sad Austin, R.C., Department of Pathology, MeMaster University, Hamilton, Ontario, LgN 37.5 and ~ Civic l-lmpitsls Research C.entrc, Hamilton, Ontario, Lgv IC3 Fibronectin, a high molecular weight cell adhesion $1ycopmteinpredueed mainly by hepatceytes, is found in basement membranes, plamna sad intentitinl cenoective timue mat:ix. It is a major component of 81omem. isr nmumginl matrix sad has been doto0ted in urine in disease Objecdw To determine if intact sad/or frngmen~ of fllmmcotin ere exeretod in the urine of diabeti~ Methods 24-hr urine samples from insulin-dependentdiabetic patients (n=20) sad control urines 0ess than 5 mg/L of albumin) were analyzed in this study. Aliqnots were concentrated .50-fold, sepm-atedon 10% SDSpolyacrylamide gels under reducing conditions and stained with Coonmssie Bdllsat Blue or western blotted and probed with affudty pure polyclonal antibody against human fibronectin, detected with alk-phosphases© conjngated goat anti-rabbit IgO. P , e ~ Sam#es from diabetic patients showed the presmce of fllmme~n and its proteoly~ fragments, whenm cootml t#me samples ~nved little or no detectable fllmmectin fingn~ts. The predominant fibmueetin fm8merits in diabetic mine, 220, 66 sad 45 kDa, correspond to fibronectin dhuen, Set~-bmding domm and hep~-bmding domain of respectively. Based on these d.t.. we conclude that mine samples from diabeti~ contain filmmectin fragments, possibly as a result of glomemisr damage.
19 17
FRUCTOSAMINE MEASUREMENTS IN A TYPE 1 A D O L F ~ C E N T DIAJBETIC POPULATION Grey. V..1 Verroneau, M. 2 Quinn, S., 1 sad Aebi, C.,2 Departmerits of BiochemistryI and Endocrinology,2 The Montreal Children's Hospital, 2300 Tupper, Montreal, Quebec, Csaad& H3H IP3
The adolescent years can be dJ~icnit for maintaining tight glycemic cunuol and frequent counselling may encourage patient compliance. Ob./e,a w To study the correimion between serum fruotomnine and mean 81ucose levels, and aesem the ruefulness of fruotosamine in aiding the msaagenumt strategy of the diabetic edole~ent Lkagn and Meamds Twenty adulesoent patien~ part of tat Adoicsoent Diabetic Education Prngram, provided records of their daily monitorin8 of capillary #ueme levels when they visited the ciinic every twn or threc weeks. Venous samples were collected for measurement of serum ~ , albumin, and 8h~=ose at eseh clinic visit. Hemnglobin Ale w u m e m ~ at the beginning ~ d end of the randy. R e ~ l ~ All patients were novmmlbuminic.A poor correlation was ob-
CLINICAL BIOCHEMISTRY:. VOLUME 28, JUNE 1995
DETECTION OF FIBRONECTIN FRAGMENTS IN URINE SAMPLES FROM DIABETICS
EVALUATION OF SPECIMEN COLLECTION TYPES FOR THE MEASUREMENT OF URINARY NTX EXCRETION, A MARKER OF BONE RESORFrION Cain. D.. Mallinak, N., and Fleasland, IC Ostex, 2203 Airport Way South, Seattle, WA, 98134, USA
Objectiwa Mcamr~nent of the urinary type I collagen erosslinked Ntelopeptides 0¢'Tx) has previously been shown to be an aceumte marker of bone resorption. (J Clin P_~oerhol Motab 1994;79:1693-1700). The NTx i m m u n ~ y , OetcomKkO (OL-x Intomatinnal, Inc., Seattle,USA) has been developed in a miorofiter kit format. Deign A prmpective clinical trial was conducted to determine the abil. ity to use a second morning void urine, which is preferable to a first morning or 24 hour collection, in the Ostcomark® assay. The clinical study laotocoi was ~icwed sad approved by each clinical site's governing Institutional Review Board, and infotmod consent was obtained for each perticipant. Five study sits across the U.S. participated. Only promenopausal women who did not have a disease, disorder, were taking or had a histoW of taking medications known to affect bone metabolism enrolled in the study.
327
39TH ANNUAL CONFERENCE OF THE CANADIAN SOCIETY OF CLINICAL CHEMISTS Results This preliminary analysis examines results obtained from 186 participants. Correlations of the three collection types were hishly si8nificant (p-0.0001). Conclusions The second momin8 void collection is a comparatively easier specimen to colh:ot in clinical practice. Compliance to the requirement of collecting a tint morning void or all urine in a 24 hour pedod as well as Iogistic~ associated with collecting and stodn8 a 24 hour urine make these types of collections unfavorable and the test results unreliable. These data support the use of the second morning urine specimen in the Osteomark® assay.
20
SKELL'TAL AIXAT ~ I E PHOSPlIATA~ (AI/~) IN IN)STMENOPAUSAL WOMEN ON F . , S T R ~ THERAPY MDS Laboratories, I00 International Blvd., Etobicoke, Ontedo, M9W 6J6, Canada
Objectives The effect of hormone ~vlacement therapy(ttRT) on serum total and skeletal ALP (biochemical markers of osteoblast activity) was studied in peat-monopeunl women. Method Patients (42-63 y) included in the study t u t i ~ e d the inclusion criteria of." intact uterus, average 3 "hot flashes"/day, amenotrheic for > 6 mo, and FSH > 40 IU/L. Patients received either F ~ r o p i p e ~ p a t e & Nomthindrune (Group 1) or Premadn/Pmmadn & Pmvera (Group 2) in an open-lsbei, quality of life audy. The mdyfical procedure for total and skeletal ALP are demfibed in (Ciin. Biochem 27;187, 1994) Results Specimens collected on enrolment and at 6 monflm (n= 53 patients) demonstrate a statistically dgnifieant decrease (at the 0.05 level) in both total md skeletal ALP for the two treatment groups. However there was no dgnificant difference between Group I and 2 at6 months for either total or skeletal ALP levels.
Earolment
6 Mo HRT
Mean +/- 2SD Toted ALP
40.4-114.7 U/L
33.7-96.9 U/L
Skeletal ALP
4.3-23.0 ug/L
4.3-18.2 ug/L
Conclusions In t~s short.term study HRT reduced oO.eobisst activity as monitored by serum total and skeletal ALP. Additional studies of clinical outcomes are required to demonstrate the benefits of long-term HRT to prevent the morbidity and mortality of bone loss in post-menopausal
measm'ed by a ec~n'qx~titiveI~.T.T~Am a y ( O ~ c e m a r ~ lad hydmxypmline by a resin-coated hydrolyals method. Urine erentiniue was assayed by a conventional method. Results: In eazh of seven female patients selected for investigation we found elevated urine levels of Nteiopepedes (> 80 nM bone collagen eqoivulents/mmol ercetinine). None of these patients, however, displayed elevated udmuy levels of hydmxyproline (ie < 400 plnol/day). A presumptive diagnosis of cetcoporosis was ,ub~quently made in each patient by bone density scans. Both markers were elevated in one patient with Paget's disease. An elevated level of N-telopeptides was also measured in a patient with mtcopetmsis. Conclusions: Our results suggest that the assay of urinary N-teiopepti&s is more sensitive than urinary hydroxyproline in the diagnosis of osteopermis. Momever, the assay may be of value in the investisation of others disorders of bone metabolism. 22
INHIBITION OF RENAL PHOSPHATE TRANSPORT BY A H U M O R A L F A C T O R I M P L I C A T E D IN ONCOGENIC OSTEOMALACIA Bondv. G.P.. Granleese, S., Wilkins, G.E., Departments of Pathology and Medicine, UBC/St. Paul's Hospital, 1081 Burrard St, Vancouver, BC, V6Z IY6, Canad&
Oncosonic ostcomalacia b a syndrome characterized by phmphaturht, hypophusphatemia, reduced vitamin D levels and osteomalaeiL These patients have a tumor which secretes a humoral factor which enusm the metabolic abnormalities. We have established a cell line (JI-I-55 cells) from an uncogenic usteomalacia tumor and we have used this cell line to identify a factor(s) which alters renal phosphate transport Objexfiw Use opossum kidney cells (OK cells) to determine the effect on phosphate transport by a humoral factor secreted by JI-I-55 cells. Methods Conditioned media was collected from JI-I-55 cells and control cell lines (A549 cells). Kidney tubular cells (OK cells) were incubated with JI-I-55 medis, A549 media and 10 nM PTH for 3 hr and24 hr. Pricephate transport was measured usin8 ssP-uptake. Results PTH and PTHrP were not detectable in the JH-55 media. JH-55 media inhibited phosphate uptake in OK cells to a level similar to 10rim PTI-L Unlike PTH, maximum inhibition required a 24 hr incubation pcfled. Ongoing protein synthesis was not required during this period. Heat (65 ° C X S rain) destroyed the activity of the JN-55 media, trypsin digestion had no effect. Conclusion We present evidence for a renal phosphate transport regulatow factor secreted by the JH-55 cells. This factor is distinct from other hormones that cause pbosphaturi&
women.
1. Ortho McNeil C a n ~ . Protocol HR91-001 "A Comparative Evaluation of a CyclophasicTM Hormone Replacement Regimen and its Effects on Quality of Life in Postmenopaussl Women".
21
A COMPARISON OF U R I N A R Y N-TELOPEFr][DES AND H Y D R O X Y P R O L I N E IN O S T E O P O R O S I S Coates, J., Chapelsky, L., Mock, T., Siminuski, K., and Yatscoff. R. Dept of Laboratory Medicine and Dept of Endocrinolosy and Metabolism, Univemity of Alberts Hospitals, Edmonton, Alberta, 1"60 2137, Canada
Objective: To compare the assay of urinary N-tclopeptides (Ostmmad~, Ostex International Inc., Seattle, Washington) and hydroxypmlioc in paficnts with Inspeoted mteoporosis. Dasign and Methods: 24-bour urine collections were ~ from patients undergoing clinical investigation of cetcoporosis. N-tclopeptides
328
23
EVALUATION OF AN IRMA FOR HUMAN OSTEOCALC1N ~chneider. W.. Hunstier-Wilheim, J., :Buchanan, D., and SChong, G., rDiv. of Medical Biochemistry, Montreal General Hospital, Montreal, Quebec H3O IA4, and Dept. of Clinicel Chemistry, 'Jewish General Huspital, Montreal, Quebec H3TE2, Canada
Ostcocalein is a 5800 Da protein synthesized by osteoblasts which is used as a specific marker of bone synthesis. Obficth, es a. To compare the Diagnostic Systems Laboratory (DSL) Osteocalcin IRMA calibrated with human mtcocalcin to our labs' current Inustar Oateocalcin RIA calibrated with bovine osteocaloin, b. To evaluate the stability of ceteocekin at room temperature and on ice. Re~lts a. When results ~ by DSL IRMA were compared to i n c ~ RIA by linear regreminn we obtained a dope of 3.73, a y interecpt of1.89, and a coct~ient (r) of 0.886 (n-96). The intar4mey ceefftclent of
CLINICAL BIOCHEMISTRY, VOLUME 28, J U N E 1995
taiued betwesa fruetmamiue sad mean #umse for the preceding twe or three weeks (r - 0.45). The vadaeon in mean 81ueose levels was high, in some imtances 8renter than 50",4 of the mean. For any individual palicnt, elumSesin fmctoeamine were minimal and did not always ~qate to mean blnod sugar. The mean 81ueme levels computed for the a i ~ - ~ ate time intervals showed • better correlation with HbAIo levels (r 0.73). Con¢iuaion The poor correlation between the mean glucose and fmctoeamine makes it dilfieult to infer the average glycemin in the pre. ceding two to three weeks and did not add to the decision-making for
managementof the patients. 16
COMPARAgSON OF IMMUNOTURBIDIMgTRIC AND FPLC METHODS FOR THE MEASUREMENT OF
18
GLYCATED H E M O G L O B I N A1¢ (HbAlc) Benin A.. Ocoffroy, L., and Dclvin, E.E., Depts of Clinical Biochemistry and Pediatri,~, Hopital Ste-Justino, Montreal, Quebec, H3T IC5, Canada Olycated HbAI e is sccoptod as an independent variable of long glyuemin control in diabetic I~den~ The DCA 2000 Odiics Canada) is an instrument wish allows a rapid i m m ~ e t r i c micrcassay. It is based on antibody specificity for the gucoas Amadori condensation product with the first three aminmekh located at the NH2-terminal end of the hemnginbin I~hain. Objecgve~ We have compared the DCA 2000 to the classicalFPLC method in terw of reproducibility, i:euracy and clinical impact. Megmds DCA 2000 and FPLC measurements were both performed on the same 72 blood samples collected at the time of the follow-up diabetes clinics. P~mdta A correlation study shows an execllent agreement between the two methods. Regression analysis gives the following equation: DCA 2000-1.063FPI~+0.003(rt-0.98). Intra- and inter-assay coefl'~eiontof variations (n-20) are 0.96 attd 2.20% respectively. The slight bias ohserved has no ulinical relevance. Variant hemoglobin content of some sample, has al~arently no efli~ on the measurement done with the DCA 2000. Results could be returned to the physician within 15 rain. after ssmple reception. Condm/on The DCA 2000 is a rapid, sensitive sad reliable method for the measurement of HbAle. It is amenable to be used in sites remote from rite central laboratory.
Eiim. e.g.. sad Austin, R.C., Department of Pathology, MeMaster University, Hamilton, Ontario, LgN 37.5 and ~ Civic l-lmpitsls Research C.entrc, Hamilton, Ontario, Lgv IC3 Fibronectin, a high molecular weight cell adhesion $1ycopmteinpredueed mainly by hepatceytes, is found in basement membranes, plamna sad intentitinl cenoective timue mat:ix. It is a major component of 81omem. isr nmumginl matrix sad has been doto0ted in urine in disease Objecdw To determine if intact sad/or frngmen~ of fllmmcotin ere exeretod in the urine of diabeti~ Methods 24-hr urine samples from insulin-dependentdiabetic patients (n=20) sad control urines 0ess than 5 mg/L of albumin) were analyzed in this study. Aliqnots were concentrated .50-fold, sepm-atedon 10% SDSpolyacrylamide gels under reducing conditions and stained with Coonmssie Bdllsat Blue or western blotted and probed with affudty pure polyclonal antibody against human fibronectin, detected with alk-phosphases© conjngated goat anti-rabbit IgO. P , e ~ Sam#es from diabetic patients showed the presmce of fllmme~n and its proteoly~ fragments, whenm cootml t#me samples ~nved little or no detectable fllmmectin fingn~ts. The predominant fibmueetin fm8merits in diabetic mine, 220, 66 sad 45 kDa, correspond to fibronectin dhuen, Set~-bmding domm and hep~-bmding domain of respectively. Based on these d.t.. we conclude that mine samples from diabeti~ contain filmmectin fragments, possibly as a result of glomemisr damage.
19 17
FRUCTOSAMINE MEASUREMENTS IN A TYPE 1 A D O L F ~ C E N T DIAJBETIC POPULATION Grey. V..1 Verroneau, M. 2 Quinn, S., 1 sad Aebi, C.,2 Departmerits of BiochemistryI and Endocrinology,2 The Montreal Children's Hospital, 2300 Tupper, Montreal, Quebec, Csaad& H3H IP3
The adolescent years can be dJ~icnit for maintaining tight glycemic cunuol and frequent counselling may encourage patient compliance. Ob./e,a w To study the correimion between serum fruotomnine and mean 81ucose levels, and aesem the ruefulness of fruotosamine in aiding the msaagenumt strategy of the diabetic edole~ent Lkagn and Meamds Twenty adulesoent patien~ part of tat Adoicsoent Diabetic Education Prngram, provided records of their daily monitorin8 of capillary #ueme levels when they visited the ciinic every twn or threc weeks. Venous samples were collected for measurement of serum ~ , albumin, and 8h~=ose at eseh clinic visit. Hemnglobin Ale w u m e m ~ at the beginning ~ d end of the randy. R e ~ l ~ All patients were novmmlbuminic.A poor correlation was ob-
CLINICAL BIOCHEMISTRY:. VOLUME 28, JUNE 1995
DETECTION OF FIBRONECTIN FRAGMENTS IN URINE SAMPLES FROM DIABETICS
EVALUATION OF SPECIMEN COLLECTION TYPES FOR THE MEASUREMENT OF URINARY NTX EXCRETION, A MARKER OF BONE RESORFrION Cain. D.. Mallinak, N., and Fleasland, IC Ostex, 2203 Airport Way South, Seattle, WA, 98134, USA
Objectiwa Mcamr~nent of the urinary type I collagen erosslinked Ntelopeptides 0¢'Tx) has previously been shown to be an aceumte marker of bone resorption. (J Clin P_~oerhol Motab 1994;79:1693-1700). The NTx i m m u n ~ y , OetcomKkO (OL-x Intomatinnal, Inc., Seattle,USA) has been developed in a miorofiter kit format. Deign A prmpective clinical trial was conducted to determine the abil. ity to use a second morning void urine, which is preferable to a first morning or 24 hour collection, in the Ostcomark® assay. The clinical study laotocoi was ~icwed sad approved by each clinical site's governing Institutional Review Board, and infotmod consent was obtained for each perticipant. Five study sits across the U.S. participated. Only promenopausal women who did not have a disease, disorder, were taking or had a histoW of taking medications known to affect bone metabolism enrolled in the study.
327
39TH ANNUAL CONFERENCE OF THE CANADIAN SOCIETY OF CLINICAL CHEMISTS Results This preliminary analysis examines results obtained from 186 participants. Correlations of the three collection types were hishly si8nificant (p-0.0001). Conclusions The second momin8 void collection is a comparatively easier specimen to colh:ot in clinical practice. Compliance to the requirement of collecting a tint morning void or all urine in a 24 hour pedod as well as Iogistic~ associated with collecting and stodn8 a 24 hour urine make these types of collections unfavorable and the test results unreliable. These data support the use of the second morning urine specimen in the Osteomark® assay.
20
SKELL'TAL AIXAT ~ I E PHOSPlIATA~ (AI/~) IN IN)STMENOPAUSAL WOMEN ON F . , S T R ~ THERAPY MDS Laboratories, I00 International Blvd., Etobicoke, Ontedo, M9W 6J6, Canada
Objectives The effect of hormone ~vlacement therapy(ttRT) on serum total and skeletal ALP (biochemical markers of osteoblast activity) was studied in peat-monopeunl women. Method Patients (42-63 y) included in the study t u t i ~ e d the inclusion criteria of." intact uterus, average 3 "hot flashes"/day, amenotrheic for > 6 mo, and FSH > 40 IU/L. Patients received either F ~ r o p i p e ~ p a t e & Nomthindrune (Group 1) or Premadn/Pmmadn & Pmvera (Group 2) in an open-lsbei, quality of life audy. The mdyfical procedure for total and skeletal ALP are demfibed in (Ciin. Biochem 27;187, 1994) Results Specimens collected on enrolment and at 6 monflm (n= 53 patients) demonstrate a statistically dgnifieant decrease (at the 0.05 level) in both total md skeletal ALP for the two treatment groups. However there was no dgnificant difference between Group I and 2 at6 months for either total or skeletal ALP levels.
Earolment
6 Mo HRT
Mean +/- 2SD Toted ALP
40.4-114.7 U/L
33.7-96.9 U/L
Skeletal ALP
4.3-23.0 ug/L
4.3-18.2 ug/L
Conclusions In t~s short.term study HRT reduced oO.eobisst activity as monitored by serum total and skeletal ALP. Additional studies of clinical outcomes are required to demonstrate the benefits of long-term HRT to prevent the morbidity and mortality of bone loss in post-menopausal
measm'ed by a ec~n'qx~titiveI~.T.T~Am a y ( O ~ c e m a r ~ lad hydmxypmline by a resin-coated hydrolyals method. Urine erentiniue was assayed by a conventional method. Results: In eazh of seven female patients selected for investigation we found elevated urine levels of Nteiopepedes (> 80 nM bone collagen eqoivulents/mmol ercetinine). None of these patients, however, displayed elevated udmuy levels of hydmxyproline (ie < 400 plnol/day). A presumptive diagnosis of cetcoporosis was ,ub~quently made in each patient by bone density scans. Both markers were elevated in one patient with Paget's disease. An elevated level of N-telopeptides was also measured in a patient with mtcopetmsis. Conclusions: Our results suggest that the assay of urinary N-teiopepti&s is more sensitive than urinary hydroxyproline in the diagnosis of osteopermis. Momever, the assay may be of value in the investisation of others disorders of bone metabolism. 22
INHIBITION OF RENAL PHOSPHATE TRANSPORT BY A H U M O R A L F A C T O R I M P L I C A T E D IN ONCOGENIC OSTEOMALACIA Bondv. G.P.. Granleese, S., Wilkins, G.E., Departments of Pathology and Medicine, UBC/St. Paul's Hospital, 1081 Burrard St, Vancouver, BC, V6Z IY6, Canad&
Oncosonic ostcomalacia b a syndrome characterized by phmphaturht, hypophusphatemia, reduced vitamin D levels and osteomalaeiL These patients have a tumor which secretes a humoral factor which enusm the metabolic abnormalities. We have established a cell line (JI-I-55 cells) from an uncogenic usteomalacia tumor and we have used this cell line to identify a factor(s) which alters renal phosphate transport Objexfiw Use opossum kidney cells (OK cells) to determine the effect on phosphate transport by a humoral factor secreted by JI-I-55 cells. Methods Conditioned media was collected from JI-I-55 cells and control cell lines (A549 cells). Kidney tubular cells (OK cells) were incubated with JI-I-55 medis, A549 media and 10 nM PTH for 3 hr and24 hr. Pricephate transport was measured usin8 ssP-uptake. Results PTH and PTHrP were not detectable in the JH-55 media. JH-55 media inhibited phosphate uptake in OK cells to a level similar to 10rim PTI-L Unlike PTH, maximum inhibition required a 24 hr incubation pcfled. Ongoing protein synthesis was not required during this period. Heat (65 ° C X S rain) destroyed the activity of the JN-55 media, trypsin digestion had no effect. Conclusion We present evidence for a renal phosphate transport regulatow factor secreted by the JH-55 cells. This factor is distinct from other hormones that cause pbosphaturi&
women.
1. Ortho McNeil C a n ~ . Protocol HR91-001 "A Comparative Evaluation of a CyclophasicTM Hormone Replacement Regimen and its Effects on Quality of Life in Postmenopaussl Women".
21
A COMPARISON OF U R I N A R Y N-TELOPEFr][DES AND H Y D R O X Y P R O L I N E IN O S T E O P O R O S I S Coates, J., Chapelsky, L., Mock, T., Siminuski, K., and Yatscoff. R. Dept of Laboratory Medicine and Dept of Endocrinolosy and Metabolism, Univemity of Alberts Hospitals, Edmonton, Alberta, 1"60 2137, Canada
Objective: To compare the assay of urinary N-tclopeptides (Ostmmad~, Ostex International Inc., Seattle, Washington) and hydroxypmlioc in paficnts with Inspeoted mteoporosis. Dasign and Methods: 24-bour urine collections were ~ from patients undergoing clinical investigation of cetcoporosis. N-tclopeptides
328
23
EVALUATION OF AN IRMA FOR HUMAN OSTEOCALC1N ~chneider. W.. Hunstier-Wilheim, J., :Buchanan, D., and SChong, G., rDiv. of Medical Biochemistry, Montreal General Hospital, Montreal, Quebec H3O IA4, and Dept. of Clinicel Chemistry, 'Jewish General Huspital, Montreal, Quebec H3TE2, Canada
Ostcocalein is a 5800 Da protein synthesized by osteoblasts which is used as a specific marker of bone synthesis. Obficth, es a. To compare the Diagnostic Systems Laboratory (DSL) Osteocalcin IRMA calibrated with human mtcocalcin to our labs' current Inustar Oateocalcin RIA calibrated with bovine osteocaloin, b. To evaluate the stability of ceteocekin at room temperature and on ice. Re~lts a. When results ~ by DSL IRMA were compared to i n c ~ RIA by linear regreminn we obtained a dope of 3.73, a y interecpt of1.89, and a coct~ient (r) of 0.886 (n-96). The intar4mey ceefftclent of
CLINICAL BIOCHEMISTRY, VOLUME 28, J U N E 1995