Effect of Changes in Body Mass Index on Cardiovascular Outcomes in Kidney Transplant Recipients

BACKGROUND

A higher body mass index (BMI) before kidney transplantation (KT) is associated with increased mortality and allograft loss in kidney transplant recipients (KTRs). However, the effect of changes in BMI after KT on these outcomes remains uncertain. The aim of this study was to investigate the effect of baseline BMI and changes in BMI on clinical outcomes in KTRs.

METHODS

A total of 869 KTRs were enrolled from a multicenter observational cohort study from 2012 to 2015. Patients were divided into low and high BMI groups before KT based on a BMI cutoff point of 23 kg/m². Differences in acute rejection and cardiovascular disease (CVD) between the 2 groups were analyzed. In addition, clinical outcomes across the 4 BMI groups divided by BMI change 1 year after KT were compared. Associations between BMI change and laboratory findings were also evaluated.

RESULTS

Patients with a higher BMI before KT showed significantly increased CVD after KT (P = .027) compared with patients with a lower BMI. However, among the KTRs with a higher baseline BMI, only persistently higher BMI was associated with increased CVD during the follow-up period (P = .003). Patients with persistently higher BMI had significantly decreased high-density lipoprotein cholesterol and increased hemoglobin, triglyceride, and hemoglobin A1c levels. Baseline BMI and post-transplantation change in BMI were not related to acute rejection in KTRs.

CONCLUSIONS

BMI in the 1st year after KT as well as baseline BMI were associated with CVD in KTRs. More careful monitoring of obese KTRs who do not undergo a reduction in BMI after KT is required.

Metabolomics Study for Identification of Potential Biomarkers of Long-term Survival in Kidney Transplantation Recipients

BACKGROUND

The recent progress and appropriate use of immunosuppressive drugs have considerably improved the short-term survival in kidney transplantation recipients (KTRs). The development of new strategies to improve long-term survival outcome after kidney transplantation is also becoming important. Although current diagnosis of allograft dysfunction relies on serum creatinine concentration and biopsy, they are nonspecific indicators of allograft function. Therefore, noninvasive, sensitive, and specific biomarkers for the prediction of long-term survival are needed. The aim of this study was to discover potential biomarkers for long-term survival in KTRs through the use of liquid chromatography-tandem mass spectrometry.

METHODS

We used the metabolic approach to explore the change of metabolites in the serum of KTRs. Twenty-four KTRs with long-term good survival (LGS) and 10 KTRs with chronic antibody-mediated rejection (CAMR) were included in this study. After quantile normalization with chromatographic data, multivariate statistical analysis was performed. We attempted to analyze metabolic profiling with LGS and CAMR groups.

RESULTS

The orthogonal partial least-squares discriminant analysis score plot showed a separation between 2 groups in the principal component. In the corresponding loading plot, 344 metabolites responsible for the separation observed in the score plot were identified (variable influence on projection ≥1.0). We then selected 54 metabolites to compare mass with charge by searching a web database, and 11 compounds were identified.

CONCLUSIONS

We found metabolites in serum that differ in LGS and CAMR groups. Further studies are needed to figure out potential metabolomic biomarkers to predict long-term survival in KTRs.

Cystatin C-Based Equation for Predicting the Glomerular Filtration Rate in Kidney Transplant Recipients

BACKGROUND

Precise monitoring of the glomerular filtration rate (GFR) is needed to estimate the allograft function in kidney transplant recipients (KTRs). The GFR is widely estimated with the use of formulas based on serum cystatin C (SCys) and serum creatinine (SCr) levels. We compared the efficacy of SCys-based equations with that of SCr-based equations to predict the allograft function.

METHODS

We calculated the Modification of Diet in Renal Disease (MDRD), Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI Cr), CKD-EPI creatinine-cystatin C (CKD-EPI Cr/Cys), and CKD-EPI cystatin C (CKD-EP ICys) equations in 70 KTRs. The measured GFR (mGFR) was defined as the GFR estimated by technetium-99m-diethylene triamine pentaacetic acid (^99mTc-DTPA) clearance. The accuracy and precision of the equations were compared with the mGFR. The performance characteristics of SCr and SCys were analyzed with the use of receiver operating characteristic (ROC) curves to ascertain the sensitivity and specificity at the cutoff value of <45 mL/min/1.73 m² DTPA.

RESULTS

Overall, MDRD and CKD-EPICys did not show significant differences from mGFR (P = .05 and P = .077, respectively), whereas CKD-EPI Cr and CKD-EPI Cr/Cys significantly underestimated mGFR (P < .001 and P = .005, respectively). In the subgroup of patients with mGFR <45 mL/min/1.73 m², CKD-EPI Cys showed little bias (P = .122), whereas MDRD significantly underestimated mGFR (P = .037). The area under the ROC curve for predicting mGFR <45 mL/min/1.73 m² was 0.80 for SCys, which was better than that for SCr at 0.763.

CONCLUSIONS

Cystatin C-based equations showed better predictive performance of the allograft function than creatinine-based equations for the KTRs, including patients with lower GFR. Cystatin C level might be a good alternate measurement to monitor the allograft function.

Clinical impact of BK virus surveillance on outcomes in kidney transplant recipients

BACKGROUND

The objective of this study was to investigate the clinical impact of BK virus surveillance on graft injury in kidney transplantation.

METHODS

BK viremia in kidney transplant recipients was evaluated by use of plasma quantitative polymerase chain reaction. The prevalence of BK viremia and BK virus-associated nephropathy (BKVAN) and the clinical impact of BK viremia on graft outcomes were assessed.

RESULTS

This study took place between January 2008 and June 2013. A total of 213 kidney transplant recipients were included. The prevalence of BK viremia and high BK viremia (≥1 × 10(4) copies/mL) was 66.7% (142/213) and 17.4% (37/213), respectively. A diagnosis of BKVAN was confirmed by means of allograft biopsy in 9 patients (4.2%). The estimated glomerular filtration rate after transplantation was similar in both the low BK viremia (<1 × 10(4) copies/mL) and non-BK viremia groups but was significantly lower in the high BK viremia group after 18 months. In receiver operating characteristic curve analysis, the area under the curve value of plasma polymerase chain reaction was 0.980. We found that a viral load >92,850 copies/mL was able to predict BKVAN with 89% sensitivity and 94.6% specificity. The risk factors for viral loads ≥1 × 10(4) copies/mL were cytomegalovirus infection, steroid pulse therapy, and acute rejection.

CONCLUSIONS

High BK viremia was associated with poor graft function after kidney transplantation. The serial monitoring of BK viremia in kidney transplant recipients was helpful in predicting BKVAN and might prevent further progression.

HLA gene dosage effect on renal allograft survival

BACKGROUND

Human leukocyte antigen (HLA)-A, HLA-B, and HLA-DR matching has beneficial long-term effects on renal allograft survival. However, the gene dosage effect of mismatched HLA on transplant outcomes is not known. We investigated the HLA gene dosage effects on allograft survival in kidney transplant recipients (KTRs).

METHODS

We analyzed HLA typing of KTRs and kidney donors at Kyungpook National University Hospital from January 1982 to December 2012. KTRs were divided into 2 groups: recipients from homozygous HLA donors and recipients from heterozygous HLA donors. Death-censored graft survival of KTRs was compared according to allele state of kidney donors.

RESULTS

In this study, 697 KTRs were enrolled. According to Kaplan-Meier analysis, graft survival in KTRs of HLA-DR and HLA-B heterozygous donors was longer than that in KTRs of HLA-DR and HLA-B homozygous donors (P = .007 and P < .0001, respectively). Multivariate Cox proportional hazards model analysis showed that HLA-DR and HLA-B donor homozygosity was an independent risk factor for death-censored graft survival (P = .019 and P = .022, respectively). Death-censored graft survival was not associated with HLA-A and HLA-A, B, DR allele states.

CONCLUSIONS

Compared with HLA donor mismatch caused by HLA-DR and HLA-B heterozygosity, HLA donor mismatch caused by HLA-DR and HLA-B homozygosity was associated with significantly increased risk of graft failure. In addition to the number of HLA mismatch between KTRs and donors, the donor allele state should be considered to predict transplant outcomes.

Application of flow cytometry to measure anti-A/B antibody in ABO-incompatible kidney transplantation

BACKGROUND

The aim of this study was to compare anti-ABO antibody levels as measured by means of flow cytometry (FCM) with the levels measured with the use of the column agglutination test (CAT), and to evaluate the clinical outcome as it relates to the baseline mean fluorescence intensity (MFI) ratio obtained by FCM.

METHODS

We reviewed 21 cases of ABO-incompatible kidney transplantation (ABO-i KT). In these patients, baseline IgG titers were measured with the use of both FCM and CAT methods. We investigated the correlation between levels measured by FCM and those by CAT with the use of correlation coefficients. Patients were classified into a high MFI ratio group (≥200; n = 7) or low MFI ratio group (<200; n = 14).

RESULTS

The MFI ratio for the FCM-based method was highly correlated with the titer measured by CAT (r = 0.890; P = .01). The relationship between MFI ratio and CAT titer can be expressed as follows: log (MFI ratio) = 0.879 × log (CAT titer) + 0.298. The number of pre-transplantation rounds of plasmapheresis significantly increased as the baseline MFI ratio increased. The allograft function was immediately recovered and stable. A single case of acute cellular rejection was observed in the low MFI ratio group.

CONCLUSIONS

Anti-ABO antibody levels measured by means of the FCM-based method were highly correlated with the levels measured with the use of CAT in cases of ABO-i KT. The decreased level of anti-ABO antibody measured by means of FCM after plasmapheresis suggests its potential as an effective and objective method for assessment of anti-ABO antibody levels.

Rhabdomyolysis associated with cytomegalovirus infection in kidney transplant recipients

Rhabdomyolysis is a pathological syndrome caused by skeletal muscle cell damage that affects the integrity of the cellular membrane and leads to the release of toxic intracellular constituents into the bloodstream. Although cytomegalovirus (CMV) has rarely been reported as a cause of rhabdomyolysis, CMV infection could be considered as a possible cause because of its clinical significance in kidney transplant recipients (KTRs). We report 2 cases of rhabdomyolysis associated with CMV infection in KTRs. A 64-year-old woman (Case 1) and a 65-year-old man (Case 2), who had each received a kidney from a living unrelated donor, were admitted with complaints of weakness in both legs and myalgia. Laboratory findings revealed highly increased creatine phosphokinase and myoglobinuria. In both cases, no recent alterations of medications had occurred, and other causes of rhabdomyolysis--such as trauma, alcohol, drugs, and electrolyte abnormalities - were excluded. CMV pp65 antigen was positive, and patients were diagnosed with rhabdomyolysis associated with CMV infection. Both patients recovered without complications after ganciclovir treatment. In conclusion, CMV infection should be considered as a possible cause of rhabdomyolysis in KTRs.

Successful withdrawal of antiviral treatment in kidney transplant recipients with chronic hepatitis B viral infection

BACKGROUND

The optimal duration of antiviral therapy for kidney transplant recipients (KTR) with chronic hepatitis B virus (HBV) infection remains unclear. We reported the long-term outcomes after withdrawal of antiviral agent in KTR with chronic HBV infection.

METHODS

We retrospectively investigated the hepatitis B surface antigen (HBsAg)-positive KTR with antiviral agents between January 2002 and January 2012. Antiviral treatments were withdrawn in patients who met all of the following 7 criteria: (i) no clinical and histologic evidence of cirrhosis, (ii) normal liver biochemistry, (iii) negative for both HBV DNA and hepatitis B envelope antigen (HBeAg), (iv) no resistance to antiviral agent, (v) antiviral therapy > 9 months, (vi) maintenance dosage of immunosuppressant for > 3 months, and (vii) no history of acute rejection during recent 6 months. All patients were followed regularly at approximately 3-6 months for liver enzyme, viral markers, and HBV DNA level after antiviral withdrawal.

RESULTS

Among a total of 445 KTR, 14 HBsAg-positive patients were included in this study. Antiviral agents were used, with lamivudine in 11 patients, and with adefovir, entecavir, and telbivudine in 3 patients, respectively. Discontinuation of antiviral agent was attempted in 6 (42.9%) of 14 patients who satisfied the criteria. The median duration of antiviral therapy before withdrawal was 14.3 months (range, 9-24 months). Four (66.7%) of 6 patients were successfully withdrawn and remained negative for HBV DNA for a median 60.5 months (range, 47-82 months). The baseline HBV DNA level was not related to maintenance of remission after withdrawal. Two reactivated patients resumed antiviral treatment immediately, with subsequent normalization of HBV DNA. During the follow-up, 1 patient developed hepatocellular carcinoma; however, no patient death or graft failure was reported for all HBsAg-positive KTR.

CONCLUSIONS

Antiviral therapy can be discontinued successfully and safely in selected KTR with chronic HBV infection, after complete suppression of HBV and sufficient duration of antiviral therapy.

ZNF313 is a novel cell cycle activator with an E3 ligase activity inhibiting cellular senescence by destabilizing p21(WAF1.)

ZNF313 encoding a zinc-binding protein is located at chromosome 20q13.13, which exhibits a frequent genomic amplification in multiple human cancers. However, the biological function of ZNF313 remains largely undefined. Here we report that ZNF313 is an ubiquitin E3 ligase that has a critical role in the regulation of cell cycle progression, differentiation and senescence. In this study, ZNF313 is initially identified as a XIAP-associated factor 1 (XAF1)-interacting protein, which upregulates the stability and proapoptotic effect of XAF1. Intriguingly, we found that ZNF313 activates cell cycle progression and suppresses cellular senescence through the RING domain-mediated degradation of p21(WAF1). ZNF313 ubiquitinates p21(WAF1) and also destabilizes p27(KIP1) and p57(KIP2), three members of the CDK-interacting protein (CIP)/kinase inhibitor protein (KIP) family of cyclin-dependent kinase inhibitors, whereas it does not affect the stability of the inhibitor of CDK (INK4) family members, such as p16(INK4A) and p15(INK4B). ZNF313 expression is tightly controlled during the cell cycle and its elevation at the late G1 phase is crucial for the G1-to-S phase transition. ZNF313 is induced by mitogenic growth factors and its blockade profoundly delays cell cycle progression and accelerates p21(WAF1)-mediated senescence. Both replicative and stress-induced senescence are accompanied with ZNF313 reduction. ZNF313 is downregulated during cellular differentiation process in vitro and in vivo, while it is commonly upregulated in many types of cancer cells. ZNF313 shows both the nuclear and cytoplasmic localization in epithelial cells of normal tissues, but exhibits an intense cytoplasmic distribution in carcinoma cells of tumor tissues. Collectively, ZNF313 is a novel E3 ligase for p21(WAF1), whose alteration might be implicated in the pathogenesis of several human diseases, including cancers.

Mycobacterium kansasii pericarditis in a kidney transplant recipient: a case report and comprehensive review of the literature

Mycobacterium kansasii is the second most common non-tuberculous mycobacteria in kidney transplant recipients (KTRs) and has been reported to cause disseminated infection in KTRs. We report the first case to our knowledge of M. kansasii pericarditis after kidney transplantation in a 54-year-old man. The patient was admitted with a 2-month history of intermittent fever and myalgia, treated with oral prednisolone and mycophenolate mofetil prior to admission. Chest computed tomography showed enlarged mediastinal lymph node and small amount of pericardial effusion. Mediastinoscopic biopsy of mediastinal lymph node revealed reactive hyperplasia, without evidence of granuloma, but acid-fast bacilli stain of pericardial fluid reported positive finding and pericardial fluid culture identified M. kansasii. The patient has been treated successfully with rifabutin-based combination therapy. All available cases of M. kansasii infection in kidney transplant patients and M. kansasii pericarditis in human immunodeficiency virus-infected patients are comprehensively reviewed.

Impact of cytochrome P450 3A and ATP-binding cassette subfamily B member 1 polymorphisms on tacrolimus dose-adjusted trough concentrations among Korean renal transplant recipients

BACKGROUND

Tacrolimus is a substrate of cytochrome P450 3A (CYP3A) and P-glycoprotein (P-gp), encoded by the CYP3A and ATP-binding cassette subfamily B member 1 (ABCB1) genes, respectively. This study was aimed to investigate the impact of CYP3A and ABCB1 polymorphisms on the tacrolimus pharmacokinetics and clinical outcomes in Korean renal transplant recipients.

METHODS

We analyzed data from a cohort of 70 renal transplant recipients receiving tacrolimus. CYP3A4*4, CYP3A4*5, CYP3A4*18, CYP3A5*3, ABCB1 C1236>T, ABCB1 G2677>T/A, and ABCB1 C3435>T polymorphisms were genotyped and correlated to dose-adjusted tacrolimus trough concentration at months 1, 3, 6, and 12 after transplantation.

RESULTS

Patients with the CYP3A5*3 alleles showed higher dose-adjusted tacrolimus concentrations for 12 months and higher trough levels until 6 months after transplantation. ABCB1 polymorphisms and haplotypes were not associated with tacrolimus concentrations. In a multivariate analysis, the presence of ≥1 CYP3A5*3 allele was a significant independent variable affecting dose-adjusted tacrolimus concentrations. Glomerular filtration rate, acute rejection, opportunistic infection, and graft survival were not affected by CYP3A5 polymorphisms. Calcineurin inhibitor toxicity, which showed higher tendency in patients with CYP3A5*1 alleles, might be associated with higher tacrolimus dose per kilogram.

CONCLUSIONS

The CYP3A5 genotype is a major factor in determining the dose requirement of tacrolimus, and genotyping may be of value in individualization of immunosuppressive therapy of renal transplant patients.

Successful kidney transplantation after desensitization using plasmapheresis, low-dose intravenous immunoglobulin, and rituximab in highly sensitized patients: a single-center experience

BACKGROUND

For many highly allosensitized renal transplant candidates, an acceptable donor is never identified, and the patient remains on dialysis indefinitely. In an attempt to ameliorate this situation, several desensitization protocols have been developed that permit positive-crossmatch kidney transplantation. Here, we report our experiences of living donor kidney transplantation in highly sensitized patients.

METHODS

We treated seven highly sensitized patients between March 2003 and September 2009. All patients underwent desensitization using pretransplant plasmapheresis (PP) and low-dose intravenous immunoglobulin (IVIG; 100 mg/kg) with rituximab (six patients) or without rituximab (one patient). Demographics, immunologic characteristics of patients, allograft function, acute rejection (AR) episodes, survival, and adverse events were evaluated.

RESULTS

Seven patients with positive-crossmatch tests or high levels of panel-reactive antibody (PRA) were included. Their mean age was 51.4 ± 3.3 years. The average number of human leukocyte antigen mismatchs was 3.4 ± 0.5. The mean percent PRA was 41.7% ± 6.1%. Six patients were crossmatch-positive, and one patient was crossmatch-negative but had high PRA levels. The mean follow-up period was 33.2 ± 5.4 months after transplantation. The all patients showed no AR episodes for follow-up period, and the patient and graft survival rates were 100%. The mean serum creatinine concentration at last follow-up was 0.92 ± 0.11 mg/dL.

CONCLUSIONS

Our experiences suggest that the combination of PP and low-dose IVIG with or without rituximab may prove effective as a desensitization regimen for positive-crossmatch and/or highly sensitized living donor renal transplant recipients. Further investigations are needed to evaluate the long-term clinical efficacy and safety of this approach.

Near-infrared spectroscopy as a possible device for continuous monitoring of arterial carbon dioxide tension during cardiac surgery

Background: Insufflation of carbon dioxide (CO2) to the operative field has been used to prevent major organ injury attributed to air embolisms in cardiac surgery. However, it may be preferable to avoid hypercapnia induced by CO2 insufflation, owing to its potentially harmful effect. To investigate the effectiveness of near-infrared spectroscopy (NIRS) as a possible method for continuous monitoring of arterial CO2 tension during cardiac surgery, we evaluated the correlation between the change in arterial CO2 tension and the change in regional cerebral oxygen saturation (rScO2) obtained from NIRS in as controlled a condition as possible.

Methods: Thirty patients who underwent surgical correction for atrial or ventricular septal defects were enrolled in this study. Patients who had pulmonary hypertension or other intracardiac anomalies were excluded. Anesthetic and cardiopulmonary bypass (CPB) management were conducted according to our standard institutional practice. Data obtained from arterial blood gas analyses and corresponding regional cerebral oxygen saturation (rScO2) recorded from NIRS before and after the insufflations of CO2 during CPB were used for analysis.

Results: The change in arterial CO2 tension correlated with the change in rScO2 in the left hemisphere (r = 0.681, p <0.001, y = −1.393 + 0.547x) and right hemisphere (r = 0.690, p <0.001, y = −1.999 + 0.486x). To control the effects of other variables, including hematocrit and temperature, these relationship were not reduced (left hemisphere: r=0.678, p<0.001; right hemisphere: r=0.634, p<0.001).

Conclusions: Since the change in regional cerebral oxygen saturation was correlated with the change in arterial CO2 tension during mild hypothermic CPB, NIRS might be a possible non-invasive method for monitoring of arterial CO2 tension without incurring additional cost in this setting.

Interleukin-18, transforming growth factor-β, and vascular endothelial growth factor gene polymorphisms and susceptibility to primary glomerulonephritis

Several studies have showed an association of gene polymorphisms with the development of glomerulonephritis (GN). We investigated the effects of gene polymorphisms on the development of GN by analyzing polymorphisms in the interleukin (IL)-18, transforming growth factor (TGF)-β, and vascular endothelial growth factor (VEGF) genes in Korean patients with primary GN. The study included 146 normal subjects (controls) and 100 patients diagnosed with primary GN by kidney biopsy. The gene polymorphisms A-607C and G-137C in IL-18, C-509T and T869C in TGF-β1, and C-2578A and C405G in VEGF were investigated in DNA extracted from peripheral blood. Significant differences were observed between the GN and control groups in the genotype and allele frequencies of A-607C IL-18 and C405G VEGF. The frequencies of the IL-18-607CC genotype [P = 0.001, odds ratio (OR) = 2.473] and the VEGF 405GG genotype (P = 0.001, OR = 2.473) were significantly increased in the GN group. The combination of IL-18-607CC+ and VEGF 405GG+ genotypes had a higher risk for developing GN in comparison with the combination of IL-18-607CC- and VEGF 405GG- genotypes (P < 0.001, OR = 8.642). In the haplotype analysis of the IL-18 gene, the CG haplotype was significantly more frequent in the GN group than the control group (61.5% vs 46.9%, P = 0.002). These results show that the -607CC genotype of the IL-18 gene and the 405GG genotype of the VEGF gene are associated with susceptibility to and the development of primary GN.

Association of C-509T and T869C polymorphisms of transforming growth factor-beta1 gene with chronic allograft nephropathy and graft survival in Korean renal transplant recipients

PURPOSE

Transforming growth factor-beta1 (TGF-beta1) has been associated with the promotion of renal allograft interstitial fibrosis and thereby chronic allograft nephropathy (CAN). The literature on TGF-beta1 polymorphisms and their importance in graft survival and CAN is not conclusive.

METHODS

TGF-beta1 gene polymorphisms (C-509T and T869C) were examined in a group of 207 Korean renal transplant recipients using real-time polymerase chain reaction assays. The CAN group (n = 18) was defined by a typical biopsy confirming CAN or chronic calcineurin inhibitor nephrotoxicity. The rest of the patients were classified into the No CAN group (n = 189).

RESULTS

No significant differences were observed in the genotype distributions of both C-509T and T869 polymorphisms between the two groups. Allele frequencies and age-, sex-, HLA mismatch-adjusted odds ratio of each genotype as assessed by logistic regression analysis were also not significantly different between the two groups. Linkage disequilibrium coefficients between polymorphisms indicated that investigated polymorphisms of TGF-beta1 (D' = 0.98) were in tight linkage. However, there were no significant differences in the frequencies of the reconstructed haplotypes between the two groups. Kaplan-Meier method and log-rank tests did not indicate any statistically significant effects of TGF-beta1 gene polymorphisms on graft survival.

CONCLUSION

TGF-beta1 gene polymorphisms (C-509T, T869C) are not significantly associated with an increased risk of development of CAN and graft survival in Korean renal transplant recipients.

Urinary Transforming Growth Factor-β–Induced Gene-h3 (βig-h3) as a Sensitive Predictor in Chronic Cyclosporine Nephrotoxicity

Transforming growth factor (TGF)-beta is involved in the pathogenesis of chronic cyclosporine nephrotoxicity (CyAN). Since the expression of TGF-beta induced gene h3 (betaig-h3) is up-regulated by TGF-beta, we evaluated the potential role of betaig-h3 as a sensitive urinary marker to monitor the progression/regression of chronic CyAN. Urinary betaig-h3 levels were determined using an enzyme-linked immunosorbent assay in nine patients with chronic CyAN and 13 patients with stable graft function. We scored the extent of tubulointerstitial fibrosis (TIF) and using immunoperoxidase labeling, determined betaig-h3 expression in renal tissues of patients with chronic CyAN. Urinary betaig-h3 excretion was higher in chronic CyAN compared to control subjects (173.4+/-26.0 vs 62.6+/-5.0 ng/mg creatinine, P<.01). In chronic CyAN, the degree of TIF correlated with increased urinary betaig-h3 levels (r=.785, P<.05). In kidneys with chronic CyAN, betaig-h3 labeling was more prominent at the basement membranes (BM) of the tubules where inflammatory cells had infiltrated the surrounding interstitium. Moreover, the BM of the atrophied tubules and their surrounding interstitium were strongly labeled. Urinary betaig-h3 levels decreased from 173.4+/-26.0 to 64.9+/-14.4 ng/mg creatinine at 1 month after discontinuation of CyA or reduction in CyA dosage (P<.01) despite unchanged serum creatinine levels. Urinary betaig-h3 levels increased in patients with chronic CyAN and decreased after discontinuation or reduction of CyA dosage. Our results suggested that urinary betaig-h3 levels could be used as a sensitive urinary marker to monitor the progression or regression of chronic CyAN.

Increased microvascular blood content is an early event in colon carcinogenesis

BACKGROUND

Increased premalignant epithelial microvascular blood content is a common theme in neoplastic transformation; however, demonstration of this phenomenon in colon carcinogenesis has been stymied by methodological limitations. Our group has recently developed a novel optics technology, four dimensional elastic light scattering fingerprinting (4D-ELF), which allows examination of the colonic mucosal architecture with unprecedented accuracy. In this study, we utilised 4D-ELF to probe the preneoplastic colonic microvasculature.

METHODS

Colonic mucosal blood content was assessed by 4D-ELF at serial preneoplastic time points from azoxymethane (AOM) treated Fisher 344 rats and age matched control animals. We also examined the pretumorigenic intestinal mucosa of the MIN mouse, and compared with wild-type mice. Finally, in a pilot study, we examined superficial blood content from the endoscopically normal mid transverse colon in 37 patients undergoing screening colonoscopy.

RESULTS

In the AOM treated rat model, augmentation of superficial mucosal and total mucosal/superficial submucosal blood supply preceded the appearance of aberrant crypt foci (ACF) and temporally and spatially correlated with future ACF occurrence. These findings were replicated in MIN mice. The 4D-ELF based results were corroborated with immunoblot analysis for haemoglobin on mucosal scrapings from AOM treated rats. Moreover, 4D-ELF analysis of normal human colonic mucosa indicated that there was a threefold increase in superficial blood in patients who harboured advanced adenomas.

CONCLUSION

We report, for the first time, that blood content is increased in the colonic microvasculature at the earliest stages of colon carcinogenesis. These findings may provide novel insights into early biological events in colorectal carcinogenesis and have potential applicability for screening.

Cytogenetic clonal evolution alone in CML relapse post-transplantation does not adversely affect response to imatinib mesylate treatment

Good prognosis after imatinib mesylate treatment has been reported if cytogenetic clonal evolution (CE) is the only criterion of accelerated phase (AP) chronic myelogenous leukemia (CML). To evaluate the impact of CE upon imatinib treatment in post-transplant settings, responses and toxicities in the relapsed AP-CE were analyzed in comparison with those in the relapsed chronic phase (CP). Both CP (n=7) and AP-CE patients (n=6) received imatinib mesylate in an oral dose of 400 mg/day. Complete cytogenetic responses were obtained in six patients of each group, CP (86%) and AC-CE (100%), while molecular remission was seen in 43 and 50%, respectively. Granulocytopenia or thrombocytopenia of grade III or more occurred in four (57%) and two (33%) patients with CP and AP-CE, respectively. Nonhematological adverse events were mild and tolerable in both groups and only one (7%) of the 13 patients experienced recurrent graft-versus-host disease after imatinib treatment. Although this is a relatively small group of patients, we suggest that imatinib mesylate should be considered as a front-line treatment for relapsed CML as it showed the high response rate and low toxicity. We also suggest that CE alone is not an important factor in the induction of cytogenetic and molecular remissions in post-transplant relapse.

Preemptive treatment of minimal residual disease post transplant in CML using real-time quantitative RT-PCR: a prospective, randomized trial

Immunotherapy in the form of donor lymphocyte infusions in early-phase relapse might be advantageous as it induces a higher response, but this may be offset by increased toxicity, especially during the early period after transplantation. Among 45 consecutive patients receiving an allograft for CML, 13 patients were diagnosed to have molecular relapse (MRel), as defined by real-time quantitative reverse transcriptase-polymerase chain reaction, and another four patients were diagnosed to have cytogenetic relapse (CRel) within 6 months. Patients with MRel were randomly assigned to either a 'no therapy' group (group A, n=6), in which immunotherapy was reserved until CRel, or an 'immunotherapy' group (group B, n=7). In group A, all MRel progressed to CRel, and molecular remission (MR) was achieved in four (67%) after immunotherapy. The remaining two patients died of extensive GVHD and fungal pneumonia. In group B, only two MRel progressed to CRel and the remaining five (71%) achieved MR. Two patients died in the absence or loss of response. In patients relapsing directly into CRel (n=4), immunotherapy induced MR in two patients (50%). Earlier intervention played a role in preventing disease progression but this effect was not translated into better survival, which could have been overcome by imatinib mesylate, which induced MR and cytogenetic remission in nonresponders without toxicity.

Effect in a rat model of heparinized peritoneal dialysis catheters on bacterial colonization and the healing of the exit site

We performed a prospective, double-blind, randomized study to evaluate whether stable surface heparinization of silicone peritoneal dialysis (PD) catheters prevents bacterial colonization or biofilm formation and improves healing of the exit site. Heparinized catheters were implanted in 20 Sprague-Dawley rats (group H) and non heparinized catheters in another 20 (group C). The PD catheters, constructed of silicon tubing with two polyester cuffs, were patterned after the standard Tenckhoff catheter. A covalent multipoint method of attachment onto polymeric surfaces was used for stable, permanent chemical immobilization of heparin on the PD catheter. Dialysis exchanges (25-mL instillation volume) were performed twice daily for 4 weeks through the permanent catheter. Prophylactic antibiotics were not used. The exit sites were evaluated at 2-week intervals. The extent of biofilm coverage on the intraperitoneal portion of the catheter (obtained at the end of the experiment) was assessed, and sonicated fluid from the catheter tip was cultured for evaluating bacterial colonization of the catheter. Exit-site scores in group H were lower than in group C (p = 0.052) at the end of week 4. Bacterial colonization tended to be less common in group H [2 of 12 catheters (17%)] than in group C [8 of 15 catheters (53%); p = 0.058], but the extent of biofilm, the peritonitis rate, and the inflammation score of tissue adjacent to the cuff were not different between the groups. Those data suggest that heparinized PD catheters can be a practical approach to the prevention of bacterial colonization and can improve healing of the exit site.

Effects of peritoneal rest on peritoneal transport and peritoneal membrane thickening in continuous ambulatory peritoneal dialysis rats

OBJECTIVE

To evaluate the effects of peritoneal rest on peritoneal transport and morphology in a rat model of peritoneal dialysis.

DESIGN

Twenty-four rats (Sprague-Dawley, male, 250-300 g) were divided into three groups: group 1 (control, n = 6) without dialysis, group 2 (n = 9) sacrificed immediately after 3 weeks of dialysis, and group 3 (n = 9) sacrificed after 4 weeks of peritoneal rest after 3 weeks of dialysis. Both dialysis groups were dialyzed twice daily with an intraperitoneal instillation volume of 25 mL of 3.86% dextrose solution for 3 weeks. Peritonitis was induced by supplementing the dialysis fluid with lipopolysaccharide (5 microg/mL) on days 8, 10, and 12 in both dialysis groups. Peritoneal equilibration tests were performed on each animal at baseline. The equilibration tests were repeated at the 4th and the 8th week of dialysis. Morphometric analyses of the peritoneal membrane were carried out in tissue specimens obtained at the time of sacrifice.

RESULTS

The D/D0 ratio for glucose at two hours in groups 2 and 3 at the beginning of week 4 was significantly lower than at baseline, indicating an increase in peritoneal permeability to glucose after 3 weeks of dialysis. D/D0 in group 3 at the beginning of week 8, after 4 weeks of peritoneal rest, was significantly higher than at week 4. The drain volume in groups 2 and 3 at week 4 was significantly lower than at baseline; however, the drain volume in group 3 at week 8 was significantly higher than at week 4. The thickness of the parietal peritoneal membrane in group 3 was significantly greater than in group 1 and less than in group 2 (group 1, 11.4+/-7.6 microm; group 2, 37.5+/-18.4 microm; group 3, 21.4+/-12.1 microm).

CONCLUSIONS

Peritoneal rest improves ultrafiltration in rats by decreasing the hyperpermeability of glucose and also reduces the degree of peritoneal thickening. These data suggest that dialysis-induced changes in peritoneal transport and morphology are reversible under the conditions of peritoneal rest in this experimental model.

Molecular cloning and analysis of transcription initiation in the Anagrapha falcifera multiple nucleocapsid polyhedrosis virus polyhedrin gene

Using Autographa californica multiple nucleocapsid polyhedrosis virus (AcMNPV) polyhedrin to probe the Southern blots of Anagrapha falcifera multiple nucleocapsid polyedrosis virus (AfMNPV), we identified the location of the AfMNPV polyhedrin gene within the 7.2 kb EcoRI fragment. The 7.2 kb EcoRI fragment of AfMNPV was cloned and the nucleotide sequences of the polyhedrin coding region and its flanking regions were determined. Nucleotide sequence analysis indicated the presence of an open reading frame (ORF) of 735 nucleotides (nt) which could encode 245 amino acids with a predicted molecular mass of 29 kDa. The nucleotide sequences within the coding region of the AfMNPV polyhedrin shared 80% similarity with the polyhedrin gene from AcMNPV but were most closely related to Bombyx mori NPV with 92% sequence identity. The size of the AfMNPV polyhedrin mRNA, determined by the Northern blot analysis, was estimated to be 1200 nt. The consensus promoter sequence (ATAAG) for the baculovirus very late gene was also observed. Two degenerate poly(A) tailing signals were found immediately downstream of the translational stop codon. The transcription initiation site, mapped by primer extension analysis, was found to be at T located 24 nt upstream from the A of the translation initiation codon. This site is located 26 nt downstream from the second A of the consensus TAAG, the transcription initiation site of most other NPVs.

Bone marrow immunoscintigraphy (BMIS): a new and important tool for the assessment of marrow fibrosis in renal osteodystrophy?

One of the classic histologic forms of renal osteodystrophy is osteitis fibrosa, and its distinguishing characteristic is bone marrow (BM) fibrosis, caused by the activation of marrow parenchymal cells. A bone biopsy must be performed in order to establish the diagnosis of renal osteodystrophy. The clinical use of bone biopsy is restricted, however, due to the invasiveness of the procedure. In recent studies, bone scans have provided information useful for the differential diagnosis between osteomalacia and osteitis fibrosa. However, bone scans can not provide information on the bone marrow status. Bone marrow immunoscintigraphy (BMIS) using Tc-99m anti-granulocyte antibody (AGA), a highly sensitive test for the detection of bone marrow abnormalities which is also a noninvasive method, has rarely been reported in chronic renal failure (CRF). BMIS can provide information in patients with myelofibrosis. The purpose of this study was to evaluate the usefulness of BMIS in CRF patients with special regards to biochemical parameters. Nineteen CRF patients (13 men, 6 women; mean age: 48 +/- 11 years) in whom bone scintigraphy using Tc-99m MDP (methylene diphosphonate) showed the so-called superscan pattern were included in the study. Their primary renal diseases were chronic glomerulonephritis (n = 14), diabetes (n = 4), and polycystic kidney disease (n = 1). Modes of therapies were continuous ambulatory peritoneal dialysis (CAPD) (n = 13; mean duration: 9.5 months), HD (n = 5; mean duration: 7.8 months), and conservative treatment (n = 1). BMIS using Tc-99m labeled anti-granulocyte monoclonal mouse antibody BW250/183 was performed, and the results were compared with the biochemical parameters of the patients. According to the presence of BM expansion, which may represent marrow fibrosis, the 19 patients were divided into two groups: Group I (n = 7) with BM expansion and Group II (n = 12) with normal marrow distribution. The biochemical parameters and bone markers of Group I were compared with those of Group II. There was no significant difference in biochemical parameters (blood hemoglobin, serum ferritin, erythropoietin, BUN, creatinine) between the two groups. There were no significants difference in serum calcium, phosphorus, tartate-resistant acid phosphatase (TRAP), and intact parathyroid hormone (iPTH) between the two groups. Serum alkaline phosphatase (ALP) and osteocalcin were significantly (P < 0.05) higher in Group I than in Group II. These results suggest that patients with bone marrow expansion in BMIS have increased levels of ALP and osteocalcin, indicating an increased osteoblastic activity. BMIS may be useful for the detection of bone marrow expansion due to marrow fibrosis in renal osteodystrophy, and for the evaluation of the extent of bone marrow fibrosis.

The absence of toxicity in intraperitoneal iron dextran administration: a functional and histological analysis

OBJECTIVE

To determine the influence of iron dextran intraperitoneal administration on the function and histology of the peritoneum in rats undergoing chronic peritoneal dialysis.

DESIGN

Prospective, randomized experimental study.

MATERIALS

Fifty-four Sprague-Dawley rats were divided into five groups: 3 study groups--high dose group (H), n = 12; intermediate dose (M), n = 12; and low dose group (L), n = 12--a dialysis control group (D), n = 12; and a tissue control (C), n = 7.

INTERVENTIONS

The study groups were given Dianeal containing iron dextran in a concentration of 0.5, 0.25, and 0.125 mg/L (groups H, M, and L respectively). Group D was given standard Dianeal. Group C was never dialyzed.

MAIN OUTCOME MEASURES

A 2-hour peritoneal equilibrium test (PET) was performed on the eighth day, at 3 months, and at 6 months. After the final PET, the animals were sacrificed and the peritoneal membrane was evaluated by gross inspection and light microscopy (silver, prussian blue, and trichrome staining).

RESULTS

Peritoneal transport of small solutes followed the same pattern in all groups, increasing over time. The peritonitis index was similar in the groups. No iron deposits or morphologic differences were seen in the gross inspection of the peritoneal cavity. No peritoneal iron deposition was detected in the histological analysis with prussian blue staining. No differences were noted in the light microscopic analysis of the mesothelial cell layer (silver staining), nor did the morphometric analysis of the submesothelial space show any differences in thickness between the groups.

CONCLUSION

These findings suggest the absence of toxic effects of iron dextran on the peritoneal cavity of rats in the concentrations studied. Further studies should be performed to evaluate the effectiveness of these dosages delivered intraperitoneally to maintain iron homeostasis.

The effect of antibiotic prophylaxis on the healing of exit sites of peritoneal dialysis catheters in rats

OBJECTIVE

To evaluate the influence of intraperitoneal (i.p.) antibiotic (AB) prophylaxis on the quality of healing and infection rates of exit sites in peritoneal dialysis catheters.

STUDY DESIGN

Twenty-one Sprague-Dawley rats were dialyzed 3 times per day for 6 weeks. Dianeal solution containing AB was used for all the rats during the first 5 days. The animals were randomized on the sixth day into three groups: group A (AB-free after randomization), group B (AB for 3 weeks), and group C (AB during 6 weeks). Scores were given to each exit site according to the observation. Mean scores from each group were compared in an attempt to find significant differences between the groups. Dialysate and exit-site drainage samples were taken weekly for microbiology.

RESULTS

Eight episodes of peritonitis were diagnosed, six in group A and two in group B. The most common bacteria causing peritonitis were gram-negative rods. The mean scores were not significantly different between groups C and B throughout the study, even after the discontinuation of the prophylaxis. Group A, when compared to the other two groups, had significantly higher scores after the second week and throughout the rest of the study.

CONCLUSION

Intraperitoneal antibiotic prophylaxis for 3 weeks after catheter implantation is an effective way to prevent early colonization of exit sites, providing a better healing quality and lower incidence of catheter-related infection. Although the extension of the prophylaxis for 6 weeks seems to be beneficial, it was not statistically proven in this study.

CAPD, an acceptable form of therapy in elderly ESRD patients: a comparative study

Rapid growth in the number of dialysis patients over the age of 65 is occurring coincidentally with the overall aging of the general population. Elderly patients are often poor and physically incapacitated, needing family or social support. These patients may also be susceptible to malnutrition and have multiple complicating medical disorders in addition to end-stage renal disease (ESRD). Thus the selection of an appropriate dialysis modality is particularly critical in elderly patients. Continuous ambulatory peritoneal dialysis (CAPD) offers many advantages to elderly patients, including hemodynamic stability, steady-state chemistries, and no need to create a vascular access. However, little data are available in the literature documenting the use of CAPD in this setting. Therefore, to evaluate the efficacy of CAPD in elderly patients, we retrospectively reviewed the clinical outcomes of 23 patients 65 years of age or older at the start of CAPD (elderly group). Then for each of these patients, 23 comparison subjects younger than 65 were chosen from CAPD patients at our hospital (control group). The control group was matched for sex, CAPD duration, cause of ESRD, and initial connection device. In the elderly group, 23 patients (12 male, 11 female) with a mean age of 70 +/- 4 years (range 65-86 years) were treated with CAPD for 15 +/- 17 months. In the control group, 23 patients (12 male, 11 female) with a mean age of 41 +/- 11 (range 18-57) were treated with CAPD for 16 +/- 17 months. Diabetic nephropathy was the cause of ESRD in 35% of patients. The negative CAPD selection of patients was higher in the elderly group (61% vs 17%, p = 0.0025) as well as in the group that needed a helper (61% vs 17%, p = 0.0025). The exit-site infection and peritonitis rates were not statistically different between the two groups (0.43 vs 0.91 episodes/patient-year and 1.46 vs 2.03 episodes/patient-year). The dialysate leakage and bleeding rates were comparable (13% vs 22% and 9% vs 9%). One-year catheter survival was similar in the elderly and younger patients (87.5% vs 84.0%). Although the negative CAPD selection of patients was higher in the elderly group, outcomes were similar to those seen in younger patients. Therefore, CAPD is an acceptable form of therapy for the elderly ESRD patients, particularly if a helper can participate.

Ultrasound-guided cannulation of the femoral vein for acute haemodialysis access

BACKGROUND

Central venous access is a mandatory part of patient management in many clinical settings and is usually achieved with a blind, external landmark-guided technique. The purpose of this study is to evaluate whether an ultrasound technique can improve on the external landmark method.

METHODS

We prospectively evaluated an ultrasound-guided method in 28 patients undergoing femoral vein cannulation for acute haemodialysis access and compared the results with 38 patients in whom an external landmark-guided technique was used. External landmark-guided technique was done by manual localization of the femoral artery in the femoral triangle inferior to the inguinal ligament with needle insertion medial to the artery. Ultrasound-guided cannulation was performed in the same location with the aid of an ultrasound device (Site-Rite, Dymax Corp., USA) with a 7.5 MHz transducer covered by a sterile sheath.

RESULTS

Cannulation of the femoral vein was achieved in all patients (100%) using ultrasound and in 34 patients (89.5%) using the landmark-guided technique. The vein was entered on the first attempt in 92.9% of patients using ultrasound and in 55.3% using the landmark technique (P < 0.05). Average access time (skin to vein) was similar but total procedure time was 45.1 +/- 18.8 s by the ultrasound approach and 79.4 +/- 61.7 s by the landmark approach (P < 0.05). Using ultrasound, puncture of the femoral artery occurred in 7.1% of patients, and haematoma in 0%. Using external landmark technique, puncture of the femoral artery occurred in 15.8% of patients, and haematoma in 2.6%.

CONCLUSIONS

Ultrasound-guided cannulation of the femoral vein reduces the time required for the procedure, reduces the number of passes needed to puncture the vein, and minimizes complications such as arterial puncture or haematoma.

Mitochondrial DNA sequence analysis of four Alzheimer's and Parkinson's disease patients

The mitochondrial DNA (mtDNA) sequence was determined on 3 patients with Alzheimer's disease (AD) exhibiting AD plus Parkinson's disease (PD) neuropathologic changes and one patient with PD. Patient mtDNA sequences were compared to the standard Cambridge sequence to identify base changes. In the first AD+PD patient, 2 of the 15 nucleotide substitutions may contribute to the neuropathology, a nucleotide pair (np) 4336 transition in the tRNA(Gln) gene found 7.4 times more frequently in patients than in controls, and a unique np 721 transition in the 12S rRNA gene which was not found in 70 other patients or 905 controls. In the second AD+PD patient, 27 nucleotide substitutions were detected, including an np 3397 transition in the ND1 gene which converts a conserved methionine to a valine. In the third AD+PD patient, 2 polymorphic base substitutions frequently found at increased frequency in Leber's hereditary optic neuropathy patients were observed, an np 4216 transition in ND1 and an np 13708 transition in the ND5 gene. For the PD patient, 2 novel variants were observed among 25 base substitutions, an np 1709 substitution in the 16S rRNA gene and an np 15851 missense mutation in the cytb gene. Further studies will be required to demonstrate a causal role for these base substitutions in neurodegenerative disease.

Detection of 17p loss in gastric carcinoma using polymerase chain reaction

BACKGROUND

The loss of heterozygosity (LOH) of 17p has been previously studied with conventional Southern blot-restriction fragment length polymorphism analysis, but the relatively low informativity was an obstacle to extensive analysis. To overcome this problem and to investigate the significance of 17p LOH in gastric carcinoma, we employed polymerase chain reaction and subsequent silver staining of DNA.

EXPERIMENTAL DESIGN

LOH of p53 gene and D17S5 locus on 17p was analyzed using polymerase reaction; the relationships between 17p LOH and conventional clinicopathologic parameters were evaluated.

RESULTS

The LOH of p53 gene and D17S5 was found in 36.5% (23 out of 63) and 63.3% (38 out of 60) informative cases, respectively. There was no significant correlation between LOH of these two loci, whereas the frequency of the D17S5 locus was significantly higher (p < 0.01), which suggested that there may be another putative tumor suppressor gene between the two loci or distal to D17S5. The LOH of p53 gene and D17S5 locus was not significantly associated with abnormal p53 expression, depth of invasion, histologic type of the tumor (Lauren's classification), or the status of lymph node metastasis.

CONCLUSIONS

The polymerase chain reaction and silver staining of DNA seemed to be a simple and excellent method for the evaluation of chromosomal allelic loss. The 17p LOH was frequently found in gastric carcinoma, but specific association with conventional clinicopathologic parameters was not found.

Induction of natural chimerism after retransplantation of the liver in rats

Immunological aspects after orthotopic rat liver retransplantation (re-OLT) were examined in association with cell migration and mixed chimerism. At day 2 after the first orthotopic liver transplantation (day 0) in the combination of DA (MHC haplotype, RT1a) donor into PVG (RT1c) recipient, the grafted DA liver was removed and a new PVG liver was implanted into the same PVG recipient (re-OLT). In the PVG recipient at various times after the re-OLT, DA-derived antigen and cells were detected using a DA-specific anti-class I mAb R3/13 in conjunction with ELISA, immunoblotting, and immunohistochemistry. The level of soluble class I antigen, which had risen to 270 ng/ml after the first OLT, substantially decreased within 24 hr after re-OLT. Using immunoblotting, DA class I antigen was detected in the PVG recipient's lymphoid organs at day 3 after DA liver grafting and persisted for up to 21 days after the DA liver was replaced by a new PVG liver. Immunohistochemistry on sections of spleen from re-OLT rats showed that the level of migratory cells expressing DA class I correlated with the findings obtained by immunoblotting. While the DA-derived antigen and cells were detected in the re-OLT recipient, the DA-specific inhibition of mixed lymphocyte reaction was observed in re-OLT serum. Our results suggest that the implanted DA liver graft was the source of DA soluble class I antigen, but DA-derived antigen and cells detected in the re-OLT recipient organs could persist for a relatively long time under immunosuppression after the implanted DA liver was removed by re-OLT.

HRAS protooncogene polymorphism and breast cancer

The potential association of polymorphism in the HRAS protooncogene variable repeat region with susceptibility to cancer has become a controversial topic. A number of studies have produced results that appear inconsistent. We report here a multidisciplinary study with a combined molecular and epidemiological approach, addressing the specific question of the association of rare HRAS alleles and breast cancer. Extensive questionnaire data and peripheral blood for DNA extraction were obtained from 160 cases of incident breast cancer and from two control groups totaling 405 unaffected women from five outpatient clinics in North Carolina between April 1990 and June 1991. Controls were frequency matched to cases on age and race. Our results, adjusted for race and age, showed a positive overall association between the presence of rare HRAS alleles and breast cancer. This relationship was somewhat stronger in control group 2 (odds ratio = 3.0; P < 0.01) than in control group 1 (odds ratio = 2.0; P < 0.05). The relationship was 3-6 times stronger in blacks than in whites. In the case series, rare HRAS alleles were associated with hormone receptor negative tumors. This association was stronger in blacks and younger women. There was no confounding or effect modification by any other breast cancer risk factors. We conclude that rare HRAS alleles are associated with breast cancer and that this association may be stronger in black women than in white women. Rare HRAS alleles may also be related to more aggressive tumors, particularly in blacks and younger women. HRAS alleles have the potential to become a valuable screening biomarker for women at increased risk for breast cancer.

Immunogenetic and nutritional profile in insulin-using youth-onset diabetics in Korea

There are few reports on the genetic, immunological and nutritional characteristics of insulin-using youth-onset diabetes mellitus, insulin-dependent diabetes mellitus (IDDM) and malnutrition-related diabetes mellitus (MRDM) in Korea. Among 1266 hospitalized Korean diabetics, 29 (2.3%) were IDDM and 84 (6.6%) were MRDM. A diabetes history of first-relatives (28.6%) was more frequently found in the MRDM group than in the IDDM (14.8) and non-insulin-dependent diabetes mellitus (NIDDM) (19.0%) groups. HLA-DR4 was more common among IDDM (54.2%) and MRDM (52.4%) patients than controls (26.3%), and HLA-DR3 was more common among only IDDM patients (29.2%) than controls (10.9%). Conventional islet-cell antibodies were detected in 8 of 15 IDDM patients tested (53.3%) and in 11 of 22 MRDM patients (50.0%). MRDM patients had higher serum basal (1.02 +/- 0.51 ng/ml) and peak (1.44 +/- 0.76 ng/ml) C-peptide concentrations than IDDM patients, but lower concentrations than NIDDM patients. Before the onset of diabetes, the calorie intake of 21 MRDM patients assessed was 63.1% of the daily requirement and the intake of carbohydrate, protein and fat was 71.7%, 55.9% and 39.8%, respectively. In summary, our data suggest that IDDM in Korea is associated with HLA-DR3 or HLA-DR4, indicating a risk for IDDM in Western societies; furthermore, MRDM has a history of undernutrition at the preonset period and is also associated with HLA-DR4. It might be also concluded that MRDM in Korea is another expression of IDDM caused by the shortage of some nutrients for the structural and/or functional maintenance of pancreatic beta-cells.

Carbamylation of hemoglobin in vivo with chronic sublethal dietary cyanide: implications for hemoglobin S

Carbamylation of the hemoglobin in sickle cell anemia has been demonstrated to improve the status of this hemoglobinopathy. Using an animal model of West African human patterns of chronic sublethal dietary cyanide ingestion, 12 miniature swine consuming either 0, 0.4, 0.7, or 1.2 mg of cyanide/kg body weight/day were studied for 24 weeks to determine if this dietary regime could produce irreversible carbamylated hemoglobin. Throughout the study, the hematological status of all animals remained similar; however, the levels of carbamylated hemoglobin as measured by nanomoles of valine hydantoin varied proportionally to dietary sublethal cyanide intakes, indicating that these natural dietary levels could effect an important and presumably permanent modification of the hemoglobin's beta chain. Serum thiocyanate levels were also positively correlated with cyanide ingestion loads (r = 0.83, P less than 0.01). The implications of these findings in swine are important for the millions of humans with hemoglobin S who regularly consume similar levels of dietary cyanide and for our assessments of the biochemical and medical status of hemoglobin S under natural conditions.

Influence of dietary cyanide on immunoglobulin and thiocyanate levels in the serum of Liberian adults

Serum thiocyanate, antibody titers to thiocyanates, and serum immunoglobulins (IgM, IgG, IgA) were measured in 73 Liberian adults normally consuming diets of low, moderate, high, or no (control) cassava-derived cyanide (CN(-)). When control and low groups (n = 40; daily intake less than 0.60 mg CN(-) per kg body weight) were contrasted with moderate and high groups (n = 33; daily intake greater than or equal to 0.60 mg CN(-) per kg body weight), the authors observed that (1) one-time serum thiocyanate measurements were not sensitive to long-term cyanide intake; however, (2) antibody titers to thiocyanates were positively correlated with cassava-based cyanide intakes (r = .22, P = 0.05); and (3) serum IgM, IgG, and IgA levels were elevated in individuals regularly consuming moderate and high levels of dietary cyanide. Possible responsible mechanisms and health implications are discussed.