Insulin-like growth factors in endometrioid adenocarcinoma: correlation with clinico-pathological features and estrogen receptor expression

Background

Endometrial carcinoma is a common malignancy of female genital tract. Insulin-like growth factor is known to elicit estrogen-induced mitogenic activity and anti-apoptotic effect in endometrial tissues.

Methods

The retrospective study investigated the expression of insulin-like growth factors, estrogen receptors and their associations in endometrioid adenocarcinoma (EAC) from 80 EAC patients in immunohistochemistry, and 58 EAC patients and 42 control patients in quantitative RT-PCR. The Pearson correlation analysis was used to analyze their correlations with clinic-pathological parameters.

Results

Our results showed that insulin-like growth factor-1 and insulin-like growth factor-2 mRNA levels were higher in tumor tissues and tumor-adjacent tissues than those in control cells, and were inversely correlated with the malignancy of the tumor with a positive correlation with ERα and ERβ expression. Insulin-like growth factor-1R protein expression was correlated with clinical stage, and insulin-like growth factor-2R protein expression was inversely correlated with histological grade.

Conclusions

Insulin-like growth factor system plays an important role in estrogen-induced endometrial carcinogenesis, and overexpression of insulin-like growth factor-1R in the advanced endometrioid adenocarcinoma is not estrogen-dependent.

Electric-field control of nonvolatile magnetization in Co40Fe40B20/Pb(Mg(1/3)Nb(2/3))(0.7)Ti(0.3)O3 structure at room temperature

We report a large and nonvolatile bipolar-electric-field-controlled magnetization at room temperature in a Co(40)Fe(40)B(20)/Pb(Mg(1/3)Nb(2/3))(0.7)Ti(0.3)O(3) structure, which exhibits an electric-field-controlled looplike magnetization. Investigations on the ferroelectric domains and crystal structures with in situ electric fields reveal that the effect is related to the combined action of 109° ferroelastic domain switching and the absence of magnetocrystalline anisotropy in Co(40)Fe(40)B(20). This work provides a route to realize large and nonvolatile magnetoelectric coupling at room temperature and is significant for applications.

[Inhibiting effect of letrozole combined with curcumin on xenografted endometrial carcinoma growth in nude mice]

BACKGROUND AND OBJECTIVE

Letrozole is an aromatase inhibitor that is used in the treatment of estrogen-sensitive tumors such as endometrial carcinoma, however, its therapeutic effect is still to be further improved. It is reported that curcumin has antitumor capability and can enhance the sensitivity of tumor cells to anticancer agents. This study was to investigate the inhibitory effect of letrozole combination with curcumin on the implanted endometrial tumor growth.

METHODS

Nude mice were implanted with endometrial carcinoma RL-952 cells. All tumor-bearing mice were randomly divided into 5 groups: control(without treatment), Let(1) (letrozole, 1 microg/d), Let(10) (letrozole, 10 microg/d), Cur [ curcumin, 300 mg/kg.d)], and Let + Cur group [10microg/d letrozole + 50mg/ (kg.d) curcumin]. The tumor growth was monitored. Tumor cells apoptosis was detected in both control and treated groups. The expressions of bcl-2 mRNA and bcl-2 protein were detected using RT-PCR and Western blot, respectively.

RESULTS

Fifty mice were successfully implanted with the endometrial tumor. Treatment with letrozole markedly inhibited tumor growth; the inhibitory effect was further enhanced by the combination of letrozole and curcumin. The inhibitory rates in Let (1), Let (10), the Cur, and the Let + Cur groups were 15.95%, 22.49%, 21.57%, and 35.89%, respectively. Treatment with curcumin inhibited the expression of bcl-2 in tumor cells at the mRNA and protein levels. The apoptosis rates in the control group and the four experimental groups mentioned above were 16.97%, 32.90%, 35.80%, 34.16%, and 47.24%, respectively. Tumor cells apoptosis were observed in mice treated with either letrozole or curcumin; however, combination of letrozole and curcumin further enhanced the inhibitory rate in tumor growth.

CONCLUSIONS

Treatment with letrozole or curcumin could inhibit the xenografted endometrial tumor growth by inducing apoptosis in tumor cells. Combination of letrozole and curcumin further enhanced the inhibitory effect of tumor growth.

Direct measurement of rotatable and frozen CoO spins in exchange bias system of CoO/Fe/Ag(001)

The exchange bias of epitaxially grown CoO/Fe/Ag(001) was investigated using x-ray magnetic circular dichroism and x-ray magnetic linear dichroism (XMLD) techniques. A direct XMLD measurement on the CoO layer during the Fe magnetization reversal shows that the CoO compensated spins are rotatable at thinner thickness and frozen at larger thickness. By a quantitative determination of the rotatable and frozen CoO spins as a function of the CoO film thickness, we find the remarkable result that the exchange bias is well established before frozen spins are detectable in the CoO film. We further show that the rotatable and frozen CoO spins are uniformly distributed in the CoO film.

Quantum-well states in a double-well system: an example of Cu/Co(Ni)/Cu

The quantum-well (QW) states in the Cu/Co double-well system are studied by first-principles calculations. We have shown that the monolayer Ni or Co as a heterogeneous spacer in Cu QW can not only disturb the QW states extending into the whole structure, but also create new QW states because of the interfaces introduced, resulting in sub-well-confining electrons. If the QW state energy in two sub-wells is close to each other, these two sub-well QW states can couple together. We have also demonstrated that monolayer Co and Ni spacers play different roles for modulating QW states at different energy levels, which also result in a complicated distribution of QW states. The obtained results are in good agreement with experiment data.

Uterus-like mass in the left broad ligament misdiagnosed as a malformation of the uterus: a case report of a rare condition and review of the literature

OBJECTIVE

To describe a rare extrauterine mass of an unknown origin that was composed of smooth muscle with a central cavity lined by endometrium, which resembled a uterus.

DESIGN

Case report.

SETTING

Academic teaching hospital.

PATIENT(S)

A 17-year-old girl with severe dysmenorrhea was found to have a uterus-like mass composed of smooth muscle and lined by endometrium in the left broad ligament.

INTERVENTION(S)

Abdominal surgery.

RESULT(S)

The mass was successfully removed surgically, and her dysmenorrhea resolved. Histopathological examination revealed that the uterus-like mass was composed of smooth muscle with a cavity lined by endometrial glands and stroma.

CONCLUSION(S)

The histogenesis of a uterus-like mass is theorized to be a Müllerian system anomaly, metaplastic change, and/or heterotopia. We believe metaplasia is the most likely cause in this case. Alhough rare, it should be considered in the differential diagnosis of dysmenorrhea of uncertain etiology.

Oscillatory magnetic anisotropy originating from quantum well states in Fe films

The magnetic anisotropy of Fe film grown on vicinal Ag(1,1,10) surfaces was studied with the in situ magneto-optic Kerr effect. Below 200 K, strong oscillations of the uniaxial magnetic anisotropy as a function of Fe thickness with a period of 5.7 monolayers are found, which can even cause the easy magnetization axis to oscillate between perpendicular and parallel to the steps. Such novel oscillation of the anisotropy is attributed to the quantum well states of d-band electrons at the Fermi level in the Fe film. This is unlike the previously observed oscillatory behaviors of ferromagnetic films caused by the quantum well states in nonmagnetic interfacing layers.

Symmetry-breaking induced exchange bias in ferromagnetic Ni-Cu-Co and Ni-Fe-Co sandwiches grown on a vicinal Cu(001) surface

Ferromagnetic Ni-Cu-Co and Ni-Fe-Co sandwiches were grown epitaxially onto a vicinal Cu(001) substrate and investigated using magneto-optical Kerr effect and x-ray magnetic circular dichroism techniques. We find that the atomic steps of the vicinal surface break the magnetic reversal symmetry to induce an exchange bias in the Ni perpendicular magnetic hysteresis loop. The Ni exchange bias direction can be switched by changing the direction of the in-plane Co magnetization. In addition, the exchange bias can be tailored by changing the Cu or Fe spacer layer thickness.

Magnetic bubble domain phase at the spin reorientation transition of ultrathin Fe/Ni/Cu(001) film

Magnetic domain phases of ultrathin Fe/Ni/Cu(001) are studied using photoemission electron microscopy at the spin reorientation transition (SRT). We observe a new magnetic phase of bubble domains within a narrow SRT region after applying a nearly in-plane magnetic field pulse to the sample. By applying the magnetic field pulse along different directions, we find that the bubble domain phase exists only if the magnetic field direction is less than approximately 10 degrees relative to the sample surface. A temperature dependent measurement shows that the bubble domain phase becomes unstable above 370 K.

Spin-dependent quantum interference from epitaxial MgO thin films on Fe(001)

Spin-dependent electron reflection from MgO thin films grown on Fe(001) was measured using spin-polarized low energy electron microscopy. The electron reflectivity exhibits quantum interference from which two MgO energy bands with Delta1 symmetry were determined in experiment. We found that a bulklike MgO energy gap is fully established for MgO film thicker than 3 atomic monolayers and that the electron reflectivity from the MgO/Fe interface exhibits a spin-dependent amplitude and a spin-independent phase change.

Body-centered-cubic Ni and its magnetic properties

The body-centered-cubic (bcc) phase of Ni, which does not exist in nature, has been achieved as a thin film on GaAs(001) at 170 K via molecular beam epitaxy. The bcc Ni is ferromagnetic with a Curie temperature of 456 K and possesses a magnetic moment of 0.52+/-0.08 micro(B)/atom. The cubic magnetocrystalline anisotropy of bcc Ni is determined to be +4.0x10(5) ergs x cm(-3), as opposed to -5.7x10(4) ergs x cm(-3) for the naturally occurring face-centered-cubic (fcc) Ni. This sharp contrast in the magnetic anisotropy is attributed to the different electronic band structures between bcc Ni and fcc Ni, which are determined using angle-resolved photoemission with synchrotron radiation.

Spin-dependent Fabry-Pérot interference from a Cu thin film grown on fcc Co(001)

Spin-dependent electron reflection from a Cu thin film grown on Co/Cu(001) was investigated using spin-polarized low-energy electron microscopy (SPLEEM). Fabry-Pe rot type interference was observed and is explained using the phase accumulation model. SPLEEM images of the Cu overlayer reveal magnetic domains in the Co underlayer, with the domain contrast oscillating with electron energy and Cu film thickness. This behavior is attributed to the spin-dependent electron reflectivity at the Cu/Co interface which leads to spin-dependent Fabry-Pe rot electron interference in the Cu film.

Magnetic stripe domains in coupled magnetic sandwiches

Magnetic stripe domains in the spin reorientation transition region are investigated in (Fe/Ni)/Cu(001) and Co/Cu/(Fe/Ni)/Cu(001) using photoemission electron microscopy. For (Fe/Ni)/Cu(001), the stripe domain width decreases exponentially as the Fe/Ni film approaches the spin reorientation transition point. For Co/Cu/(Fe/Ni)/Cu(001), the Fe/Ni stripe orientation is aligned with the Co in-plane magnetization, and the stripe domain width decreases exponentially with increasing the interlayer coupling between the Fe/Ni and Co films. By considering magnetic stripes within an in-plane magnetic field, we reveal a universal dependence of the stripe domain width on the magnetic anisotropy and on the interlayer coupling.

Magnetic phase transition in Co/Cu/Ni/Cu(100) and Co/Fe/Ni/Cu(100)

Magnetic phase transitions in coupled magnetic sandwiches of Cu/Co/Cu/Ni/Cu(100) and Cu/Co/Fe/Ni/Cu(100) are investigated by photoemission electron microscopy. Element-specific magnetic domains are taken at room temperature to reveal the critical thickness at which the magnetic phase transition occurs. The results show that a coupled magnetic sandwich undergoes three types of magnetic phase transitions depending on the two ferromagnetic films' thickness. A phase diagram is constructed and explained in the process of constructing Monte Carlo simulations, which corroborate the experimental results.

The simulation of 31P NMR line shapes of lipid bilayers using an analytically soluble model

Van Faassen's method for obtaining an explicit solution to a first order stochastic differential equation is applied to the simulation of 31P NMR line shapes of unoriented phospholipid bilayers in the Lalpha phase and of oriented bilayers in both the Lalpha and Lbeta' phases. The effects of the two slowest motions on the density matrix are described by the stochastic Liouville equation (SLE) which is solved analytically using the method of van Faassen. These two slowest motions are assumed to be a rotational re-orientation about the long molecular axis and a uniform wobble of this axis within a conical volume with re-orientation rates characterised by correlation times tau(parallel) and tau(perpendicular) respectively. In the present work the Hamiltonian contains the intramolecular dipole-dipole interaction between the phosphorous nucleus and the four closest methylene protons of the choline headgroup, as well as the anisotropic chemical shielding interaction. Hence the contribution to relaxation from cross correlation between the dipole-dipole and anisotropic chemical shielding interactions is included. The reorientation of the headgroup is assumed to be a rotation sufficiently fast to lead to complete axially symmetric averaging of the Hamiltonian about the rotational axis (the P-O11 bond axis). Evaluation of the line shape in the present work involves only numerical integration and is therefore less computationally demanding than the large matrix inversions involved in the approaches of Campbell, Freed et al. The present theory also uses fewer parameters than that of Dufourc et al. but nevertheless results in good agreement with these authors' measurements on DMPC bilayers, using a fixed value of 10 for the ratio tau(perpendicular)/tau(parallel) in the case of the Lalpha phase. However, in contrast to Dufourc et al., we find that these correlation times are equal for the Lbeta' phase. Finally, we have simulated the decoupled powder line shapes obtained from the Lbeta' phase of DPPC by Campbell and Meirovitch. Again, we get good agreement providing tau(perpendicular)=tau(parallel).

Secondary sulphonylurea failure: what pathogenesis is responsible?

Sulphonylurea (SU) stimulates insulin secretion by pancreatic beta-cells and is generally used as a first-line treatment for type 2 diabetes. However, after long-term SU treatment (six months or over), some patients begin to show an increase in blood glucose once again (secondary SU failure). Two theories have been put forward to explain this failure--dysfunction of the proinsulin conversion machinery or insulin resistance. However, the primary pathogenesis behind secondary SU failure still needs to be investigated. Using a reliable technique that specifically identifies intact proinsulin (IPI), total proinsulin (TPI) and specific insulin (SI), this study aims to discover if a defect in the proinsulin converting mechanism plays a role in SU failure. Three groups were recruited for this study: healthy controls (n=8), SU responders (n=38) and secondary SU failures (n= 46). Serum concentrations of insulin-related molecules released in response to a standard glucose challenge test were compared between the groups. It was found that total SI was lower in the patient groups (P<0.05 compared to the control group), while TPI and IPI showed no distinct difference between the three groups (P>0.05). TPI:SI ratio and IPI:SI ratio showed marked increases in the patient groups (P<0.05 compared to control group), with no obvious quantitative difference between SU responders and secondary SU failures (P>0.05). Similar results for the Homa Insulin Resistant Index were found between the two patient groups. Interestingly, blood glucose at 180 mins after glucose challenge was significantly higher in the secondary SU failure group (P<0.05), with no correlation to SI, while the SU responder group showed good correlation between the parameters (P<0.05). We conclude that type 2 diabetes is associated with obvious dysfunction in the proinsulin-converting process and shows severe SI deficiency in responding to glucose challenge. Dysfunction of the proinsulin conversion mechanism was not an extra cause responsible for SU failure.

[Angiogenesis and micrometastases of regional lymph node in ovarian cancer]

BACKGROUND & OBJECTIVE

In many investigation it was demonstrated that intratumor microvessel density (IMD) is the best factor for no tumor survival for patients with ovarian cancer. Occult axillary node micrometastases as the prognostic factor for the patients with breast cancer was proved, but currently no literature of the pelvic lymph node micrometastases in ovarian cancer is provided. This study try to detect the microvessel density of tumor tissues and micrometastases of regional lymph nodes in ovarian cancer and to investigate the relationship between these two factors and their prognostic significance.

METHODS

The sections of ovarian cancer from 39 patients were stained immunohistochemically for cytokeratin(CK) and factor VIII-related antigen (F8-RA). Microvessels on the section were counted by computerized morphometry (40 fields). Sections of 212 regional lymph nodes from 39 patients were stained also with HE and CK.

RESULTS

(1)We found 7 lymph node metastases with HE staining in 39 patients and 12 micrometastases with CK staining.(2) Average value of intratumor microvessel density (IMD) in the HE positive group was 48.86+/-16.60 and was obviously higher than that in the HE negative group (29.16+/-10.02,P< 0.01). The average IMD was 41.67+/-21.69 in the CK positive group and was also obviously higher than that in the CK negative group (28.70+/-10.77,P< 0.05). We found 8(50%) micrometastases in 16 patients with higher IMD (> or = 30/40 x fields) and only 4(17.4%) micrometastases in 23 patients with lower IMD (< 30/40 x fields), the difference was significant (P< 0.05). (3)IMD (P=0.03) and regional lymph node micrometastases(P=0.04) were the most significant factors to the survival time through Cox proportional hezard model analysis,the IMD (P=0.0008) and clinical stage (P=0.03) were also the most important factors to predict recurrence.

CONCLUSION

The study suggests the CK immunohistochemical staining could detect the micrometastases in the HE negative lymph node in patients with epithelial ovarian cancer. The IMD is closely related to the micrometastases and these two factors have prognostic significance in ovarian cancer. The IMD and micrometastases could act as independent prognosis factors of patients with ovarian cancer.

[LC/MS research on the isomers of special melanoma antigen-encoding gene-2 epitope peptide induced by solvent]

To study the influence of different solvent systems on the isomers of melanoma antigen-encoding gene-2(MAGE-2) epitope peptide synthesized by Marrifield's solid synthesis method, MAGE-2(171-179) epitope peptides were pre-treated using ethanol and methanol systems respectively, and then analysed by RP-HPLC/MS, with dimethyl-sulphoxide (DMSO) as control solvent. Results demonstrated that 100% ethanol and 100% methanol solvents could induce the production of isomers of MAGE-2, while 100% DMSO, 50% ethanol and 50% methanol could not. These isomeric peptides could be reversed greatly if treated with trifluoroacetic acid (TFA). The results also showed that the analysis would be distorted and the yield of peptides would decrease dramatically if the peptides were pre-treated with high concentrations of ethanol and methanol before RP-HPLC analysis and preparation. Thus it is suggested that it might be better to decrease the concentration of organic phase in the solvent system for the resolvable hydrophobic peptides, acidified ethanol and methanol might also be better for the highly hydrophobic peptides, and DMSO would be a good solvent for hydrophobic peptides analysis provided that it would not influence the resolving power of chromatography.

[CT diagnosis of maxillary mucoceles]

CT signs of thirty-six cases of maxillary mucocele surgically and pathologically proved were analyzed. 20 of 36 cases revealed as low density lesion. 16 of 36 cases revealed as isodensity or high density lesion. They were morphologically classified as three types: nodular type, inflammatory type, bony defect type. Cystic morphology and fluid density within the lesion obviously indicated mucocele. Differential diagnosis should be made between mucocele and polyps, when the lesion revealed as soft tissue density. Inflammatory type need to be distinguished from maxillary inflammation. And bony defect type should be distinguished from the benign or malignant tumor of maxillary sinus. The islet sign and bone sclerosis are considered to be valuable for the differential diagnosis.

[CT diagnosis of hemorrhagic renal cysts]

CT signs of nineteen cases of hemorrhagic renal cysts that surgically and pathologically proved were analyzed. 8 of the 19 cases revealed as high density hemorrhagic lesion. CT signs in those 8 patients include low density rim sign, cyst immerging sign, and perirenal fascia thickening. The other 11 of 19 cases revealed as low density lesion. CT signs include thickened cyst wall and inhomogeneous density of the cystic content. The hounsfield unit of the lesion is correlated with the duration of disease. It is suggested that CT is valuable in diagnosis of high density hemorrhagic renal cysts, and it gives a clue to the diagnosis of low density hemorrhagic renal cysts.

Indirubins inhibit glycogen synthase kinase-3 beta and CDK5/p25, two protein kinases involved in abnormal tau phosphorylation in Alzheimer's disease. A property common to most cyclin-dependent kinase inhibitors?

The bis-indole indirubin is an active ingredient of Danggui Longhui Wan, a traditional Chinese medicine recipe used in the treatment of chronic diseases such as leukemias. The antitumoral properties of indirubin appear to correlate with their antimitotic effects. Indirubins were recently described as potent (IC(50): 50-100 nm) inhibitors of cyclin-dependent kinases (CDKs). We report here that indirubins are also powerful inhibitors (IC(50): 5-50 nm) of an evolutionarily related kinase, glycogen synthase kinase-3beta (GSK-3 beta). Testing of a series of indoles and bis-indoles against GSK-3 beta, CDK1/cyclin B, and CDK5/p25 shows that only indirubins inhibit these kinases. The structure-activity relationship study also suggests that indirubins bind to GSK-3 beta's ATP binding pocket in a way similar to their binding to CDKs, the details of which were recently revealed by crystallographic analysis. GSK-3 beta, along with CDK5, is responsible for most of the abnormal hyperphosphorylation of the microtubule-binding protein tau observed in Alzheimer's disease. Indirubin-3'-monoxime inhibits tau phosphorylation in vitro and in vivo at Alzheimer's disease-specific sites. Indirubins may thus have important implications in the study and treatment of neurodegenerative disorders. Indirubin-3'-monoxime also inhibits the in vivo phosphorylation of DARPP-32 by CDK5 on Thr-75, thereby mimicking one of the effects of dopamine in the striatum. Finally, we show that many, but not all, reported CDK inhibitors are powerful inhibitors of GSK-3 beta. To which extent these GSK-3 beta effects of CDK inhibitors actually contribute to their antimitotic and antitumoral properties remains to be determined. Indirubins constitute the first family of low nanomolar inhibitors of GSK-3 beta to be described.

Mechanisms mediating the effects of IL-3 gene expression on tumor growth

IL-3 gene expression within tumors leads to host-cell infiltration, particularly by macrophages, slower tumor growth, and enhanced immunogenicity. Surprisingly, tumor-associated macrophages (TAMs) from within FSAN-JmIL3 tumors had decreased expression of TNF-alpha and iNOS. On short-term culture, TAMs from FSAN-JmIL3 tumors regained their capacity to produce TNF-alpha and NO, indicating that they were primed in vivo. In vitro experiments were unable to demonstrate differences between FSAN-JmIL3 and FSAN tumor cells in their ability to stimulate TNF-alpha production by TAMs. In the absence of evidence that TAM activation was responsible for the slower growth of FSAN-JmIL3 tumors, the response of tumor cells to these effector molecules was studied. TNF-alpha and NO were cytotoxic for FSAN-JmIL3 cells but growth stimulatory for FSAN. These tumor-related phenotypic changes may contribute as much if not more than functional changes in host infiltrating cells to the slower growth of FSAN-JmIL3 tumors in vivo.

Paullones are potent inhibitors of glycogen synthase kinase-3beta and cyclin-dependent kinase 5/p25

Paullones constitute a new family of benzazepinones with promising antitumoral properties. They were recently described as potent, ATP-competitive, inhibitors of the cell cycle regulating cyclin-dependent kinases (CDKs). We here report that paullones also act as very potent inhibitors of glycogen synthase kinase-3beta (GSK-3beta) (IC50: 4-80 nM) and the neuronal CDK5/p25 (IC50: 20-200 nM). These two enzymes are responsible for most of the hyperphosphorylation of the microtubule-binding protein tau, a feature observed in the brains of patients with Alzheimer's disease and other neurodegenerative 'taupathies'. Alsterpaullone, the most active paullone, was demonstrated to act by competing with ATP for binding to GSK-3beta. Alsterpaullone inhibits the phosphorylation of tau in vivo at sites which are typically phosphorylated by GSK-3beta in Alzheimer's disease. Alsterpaullone also inhibits the CDK5/p25-dependent phosphorylation of DARPP-32 in mouse striatum slices in vitro. This dual specificity of paullones may turn these compounds into very useful tools for the study and possibly treatment of neurodegenerative and proliferative disorders.

Cardiac troponin I: a marker for post-burn cardiac injury

Cardiac troponin I (cTnI) was measured by chemiluminescent immunoassay following burn injury. Thirty patients [total body surface area (TBSA) of burn 15-98%] were included in this study and each had four to six blood samples collected at 2-day intervals between the 5th and 14th days post-burn. All patients were found to have increased cTnI on two or more occasions. The mean cTnI concentration was significantly higher in patients with TBSA of burn > 30% (0.34 microg/L compared with 0.09 microg/L, P<0.001) and in those with obvious burn wound exudation (0.32 microg/L compared with 0.12 microg/L, P<0.01). cTnI concentrations peaked at the time when there was obvious burn wound exudation or spontaneous separation of eschar, then decreased after surgical excision. Two patients with persistently high cTnI concentrations developed tachycardia. We conclude that burned patients have varying degrees of non-ischaemic cardiac injury, manifesting as leakage of cTnI from myocytes into the circulation.