[Short-term outcomes of the TRIANGLE operation after neoadjuvant chemotherapy in locally advanced pancreatic cancer]

Objective: To investigate the safety and efficacy of the TRIANGLE operation after neoadjuvant chemotherapy in locally advanced pancreatic cancer(LAPC). Methods: This study is a retrospective case series analysis. Between January 2020 and December 2022, a total of 103 patients were diagnosed as LAPC who underwent neoadjuvant chemotherapy at the Pancreas Center, the First Affiliated Hospital of Nanjing Medical University. Among them, 26 patients (25.2%) underwent the TRIANGLE operation. There were 15 males and 11 females,with a age of (59±7) years (range: 49 to 74 years). The pre-treatment serum CA19-9(M(IQR)) was 248.8(391.6)U/ml (range: 0 to 1 428 U/ml),and the serum carcinoembryonic antigen was 4.1(3.8)μg/L(range: 1.4 to 13.4 μg/L). The neoadjuvant chemotherapy regimens included: mFOLFIRINOX regimen in 6 cases(23.1%), GnP regimen in 14 cases(53.8%), and mFOLFIRINOX+GnP regimen in 6 cases(23.1%). The follow-up duration extended until June 2023 or until the occurrence of the patient's death or loss to follow-up. The Kaplan-Meier method was employed to estimate the 1-year and 3-year overall survival rates. Results: After neoadjuvant chemotherapy,CA19-9 levels decreased by 92.3(40.1)%(range:2.1% to 97.7%). Evaluation of the response to treatment revealed 13 cases(50.0%) of stable disease,11 cases(42.3%) of partial response,and 2 cases(7.7%) of complete response. The surgical operation consisted of 12 cases(46.2%) of pancreaticoduodenectomy,12 cases(46.2%) of distal pancreatectomy,and 2 cases(7.7%) of total pancreatectomy. Margin determination was based on the "standardised pathology protocol" and the "1 mm" principle. No R2 and R1(direct) resections were observed,while the R0 resection rate was 61.5%(16/26), and the R1(1 mm) resection rate was 38.5%(10/26).The R1(1 mm) resection rates for the anterior margin,posterior margin,transected margin,portal vein groove margin,and uncinate margin were 23.1%(6/26),19.2%(5/26),12.5%(3/24),2/14, and 1/12, respectively. The overall postoperative complication rate was 57.8%(15/26),with major complications including grade B/C pancreatic fistula 25.0%(6/24,excluding 2 cases of total pancreatectomy),delayed gastric emptying in 23.1%(6/26),wound complications 11.5%(3/26),postoperative hemorrhage 7.7%(2/26), chylous fistula 7.7%(2/26) and bile fistula 3.8%(1/26). No reoperation was performed during the perioperative period(<90 days). One patient died on the 32nd day postoperatively due to a ruptured pseudoaneurysm. A total of 25 patients were followed up,with a follow-up time of 21(24)months(range: 8 to 42 months). During the follow-up period,8 cases(32.0%) died due to tumor recurrence and metastasis,while 17 patients(68.0%) remained alive,including 11 cases of disease-free survival,5 cases of distant metastasis,and 1 case of local recurrence. The overall survival rates at 1- and 3-year after the initiation of neoadjuvant chemotherapy were 95.8% and 58.9%, respectively. The overall survival rates at 1- and 3-year after surgery were 77.7% and 57.8%, respectively. Conclusion: Performing pancreatoduodenectomy according to the Heidelberg triangle protocol in LAPC patients after neoadjuvant chemotherapy might increase the R0 resection rate without increasing perioperative mortality or the incidence of major postoperative complications.

[Distal pancreatectomy with celiac axis resection for pancreatic body cancer: a single center review of 89 consecutive cases]

Objective: To investigate the clinical efficacy of distal pancreatectomy with celiac axis resection(DP-CAR). Methods: A total of 89 consecutive patients (50 males and 39 females) who were diagnosed with pancreatic body cancer and underwent DP-CAR in Pancreas Center,First Affiliated Hospital of Nanjing Medical University between September 2013 and June 2022 were retrospectively reviewed. There were 50 males and 39 females,with age(M(IQR)) of 63(12) years(range:43 to 81 years). Perioperative parameters,pathology results and follow-up data of these patients were analyzed,χ2 or Fisher's test for categorical data while the Wilcoxon test for quantitative data. Survival results were estimated by the Kaplan-Meier survival method. Results: Among 89 cases,cases combined with portal vein-superior mesenteric vein or organ resection accounted for 22.5% (20/89) and 42.7% (38/89),respectively. The operative time,blood loss and postoperative hospital stay were 270 (110) minutes,300 (300) ml and 13 (10) days,respectively. The overall morbidity rate was 67.4% (60/89) while the major morbidity was 11.2% (10/89). The increase rate in transient liver enzymes was 42.7% (38/89),3.4% (3/89) for liver failure,53.9% (48/89) for clinically relevant postoperative pancreatic fistula,1.1% (1/89) for bile leak,3.4% (3/89) for chylous leak of grade B and C,11.2% (10/89) for abdominal infection,9.0% (8/89) for postoperative hemorrhage of grade B and C,4.5% (4/89) for delayed gastric emptying,6.7% (6/89) for deep vein thrombosis,3.4% (3/89) for reoperation,4.5% (4/89)for hospital mortality,7.9% (7/89) for 90-day mortality. The pathological type was pancreatic cancer for all 89 cases and pancreatic ductal adenocarcinoma made up 92.1% (82/89). The tumor size was 4.8(2.0) cm, ranging from 1.5 to 12.0 cm. The number of lymph nodes harvested was 14 (13)(range:2 to 33),with a positive lymph node rate of 13.0% (24.0%). The resection R0 rate was 30.0% (24/80) and the R1 (<1 mm) rate was 58.8% (47/80). The median overall survival time was 21.3 months (95%CI: 15.6 to 24.3) and the median disease-free survival time was 19.1 months (95%CI: 11.7 to 25.1). The overall survival at 1-year and 2-year were 69.60% and 39.52%. The median survival time of 58 patients with adjuvant chemotherapy was 24.3 months (95%CI: 17.8 to 32.3) while that of 13 patients without any kind of adjuvant therapy was 8.4 months (95%CI: 7.3 to 22.3). Seven patients accepted neoadjuvant chemotherapy and there was no significant morbidity among them,with a resection rate of R0 of 5/7. Conclusion: DP-CAR is safe and feasible for selective cases,which could be more valuable in improving long-term survival when combined with (neo) adjuvant therapy.

[Clinical value of lymph node dissection of No. 14cd during pancreaticoduodenectomy in patients with pancreatic head carcinoma]

Objectives: To evaluate the positive rate of left posterior lymph nodes of the superior mesenteric artery (14cd-LN) in patients undergoing pancreaticoduodenectomy for pancreatic head carcinoma,to analyze the impact of 14cd-LN dissection on lymph node staging and tumor TNM staging. Methods: The clinical and pathological data of 103 consecutive patients with pancreatic cancer who underwent pancreaticoduodenectomy at Pancreatic Center,the First Affiliated Hospital of Nanjing Medical University from January to December 2022 were analyzed,retrospectively. There were 69 males and 34 females,with an age(M (IQR))of 63.0 (14.0) years (range:48.0 to 86.0 years). The χ² test and Fisher's exact probability method was used for comparison of the count data between the groups,respectively. The rank sum test was used for comparison of the measurement data between groups. Univariate and multivariate Logistic regression analyzes were used for the analysis of risk factors. Results: All 103 patients underwent pancreaticoduodenectomy successfully using the left-sided uncinate process and the artery first approach. Pathological examination showed pancreatic ductal adenocarcinoma in all cases. The location of the tumors was the pancreatic head in 40 cases,pancreatic head-uncinate in 45 cases,and pancreatic head-neck in 18 cases. Of the 103 patients,38 cases had moderately differentiated tumor and 65 cases had poorly differentiated tumor. The diameter of the lesions was 3.2 (0.8) cm (range:1.7 to 6.5 cm),the number of lymph nodes harvested was 25 (10) (range:11 to 53),and the number of positive lymph nodes was 1 (3) (range:0 to 40). The lymph node stage was stage N0 in 35 cases (34.0%),stage N1 in 43 cases (41.7%),and stage N2 in 25 cases (24.3%). TNM staging was stage ⅠA in 5 cases (4.9%),stage ⅠB in 19 cases (18.4%),stage ⅡA in 2 cases (1.9%),stage ⅡB in 38 cases (36.9%),stage Ⅲ in 38 cases (36.9%),and stage Ⅳ in 1 case (1.0%). In 103 patients with pancreatic head cancer,the overall positivity rate for 14cd-LN was 31.1% (32/103),and the positive rates for 14c-LN and 14d-LN were 21.4% (22/103) and 18.4% (19/103),respectively. 14cd-LN dissection increased the number of lymph nodes (P<0.01) and positive lymph nodes (P<0.01). As a result of the 14cd-LN dissection,the lymph node stage was changed in 6 patients,including 5 patients changed from N0 to N1 and 1 patient changed from N1 to N2. Similarly,the TNM stage was changed in 5 patients,including 2 patients changed from stage ⅠB to ⅡB,2 patients changed from stage ⅡA to ⅡB,and 1 patient changed from stage ⅡB to Ⅲ. Tumors located in the pancreatic head-uncinate (OR=3.43,95%CI:1.08 to 10.93,P=0.037) and the positivity of 7,8,9,12 LN (OR=5.45,95%CI:1.45 to 20.44,P=0.012) were independent risk factors for 14c-LN metastasis; while tumors with diameter >3 cm (OR=3.93,95%CI:1.08 to 14.33,P=0.038) and the positivity of 7,8,9,12 LN (OR=11.09,95%CI:2.69 to 45.80,P=0.001) were independent risk factors for 14d-LN metastasis. Conclusion: Due to its high positive rate in pancreatic head cancer,dissection of 14cd-LN during pancreaticoduodenectomy should be recommended,which can increase the number of lymph nodes harvested,provide a more accurate lymph node staging and TNM staging.

[Comparative clinical efficacy analysis of pancreatoduodenectomy for distal bile duct and pancreatic head cancer: a report of 1 005 cases]

Objective: To compare and analyze the clinical efficacy of pancreaticoduodenectomy for distal bile duct cancer and pancreatic head cancer. Methods: Clinical data of 1 005 patients who underwent pancreaticoduodenectomy and postoperative pathological examination confirmed the diagnosis of distal bile duct cancer and pancreatic head cancer at the Pancreas Center of the First Affiliated Hospital of Nanjing Medical University from January 2016 to December 2020 were analyzed retrospectively. There were 112 cases in the distal bile duct cancer group, 71 males and 41 females,with age (M(IQR)) of 65(15) years(range: 40 to 87 years); 893 cases in the pancreatic head cancer group, 534 males and 359 females,with age of 64(13)years(range: 16 to 91 years). The differences between clinicopathological characteristics and postoperative overall survival of the two groups were analyzed by χ² test, Fisher's exact probability method, rank sum test or log-rank test, respectively. The difference in postoperative overall survival between the two groups was compared using Kaplan-Meier method after propensity score matching (1∶1). Results: Compared with the pancreatic head cancer group,the distal bile duct cancer group had shorter operative time (240.0(134.0) minutes vs. 261.0(97.0) minutes, Z=2.712, P=0.007),less proportion of combined venous resection (4.5% (5/112) vs. 19.4% (173/893), χ²=15.177,P<0.01),smaller tumor diameter (2.0(1.0) cm vs. 3.0(1.5) cm,Z=10.567,P<0.01),higher well/moderate differentiation ratio (51.4% (56/112) vs. 38.0% (337/893), χ²=7.328, P=0.007),fewer positive lymph nodes (0(1) vs. 1(3), Z=5.824, P<0.01),and higher R0 resection rate (77.7% (87/112) vs. 38.3%(342/893), χ²=64.399, P<0.01),but with a higher incidence of overall postoperative complications (50.0% (56/112) vs. 36.3% (324/892), χ²=7.913,P=0.005),postoperative pancreatic fistula (28.6% (32/112) vs. 13.9% (124/893), χ²=16.318,P<0.01),and postoperative abdominal infection (21.4% (24/112) vs. 8.6% (77/892), χ²=18.001,P<0.01). After propensity score matching, there was no statistical difference in postoperative overall survival time between patients in the distal bile duct cancer group and the pancreatic head cancer group (50.6 months vs. 35.1 months,Z=1.640,P=0.201),and multifactorial analysis showed that tumor site was not an independent risk factor affecting the prognosis of patients in both groups after matching (HR=0.73,95%CI:0.43 to 1.23,P=0.238). Conclusions: Patients with distal bile duct cancer are more likely to benefit from early diagnosis and surgical treatment than patients with pancreatic head cancer,but with a relative higher postoperative complication rates. The different tumor origin site is not an independent risk factor for prognosis of patients with distal bile duct cancer and pancreatic head cancer after propensity score matching.

[Application of left-sided uncinate process first approach in pancreaticoduodenectomy]

Objective: To evaluate the value of left-sided uncinate process first approach in pancreaticoduodenectomy. Methods: The clinical data of 152 patients who underwent the left-sided uncinate process first approach during pancreaticoduodenectomy at Pancreas Center, the First Affiliated Hospital of Nanjing Medical University from January 2020 to December 2020 were analyzed retrospectively. There were 64 females and 88 males,with age(M(Q_R)) of 62.0(14.7)years(range:16.0 to 84.0 years). The clinical date of 117 patients who underwent pancreaticoduodenectomy without using left-sided uncinate process first approach in the same period was selected as the control group,including 65 females and 52 males,with age of 64.0(13.0) years(range:13.0 to 84.0 years). Fisher exact probability method and t test were used to compare the data between the two groups,rank sum test was used for comparison of continuous variables between the two groups. Results: Pancreaticoduodenectomy was successfully performed in 152 patients in left-sided uncinate process first approach group. The operation time was 222.5(77.0) minutes(range:117.0 to 480.0 minutes),the time of uncinate process resection from left-side(the time from jejunum dissection to complete dissociation of the uncinate process) was 11.0(4.5) minutes(range:7.5 to 20.0 minutes),the time of pancreatic head resection (the time from jejunum dissection to pancreaticoduodenal specimen removal) was 26.0(8.5) minutes(range:20.0 to 41.0 minutes),the intraoperative blood loss was 200(150) ml(range:50 to 800 ml),and the intraoperative blood transfusion rate was 9.2% (14/152). Postoperative conditions:The postoperative hospital stay was 12 (9) d(range:6 to 55 d),the overall incidence of postoperative complications was 59.9%(91/152),and there was no perioperative death. Pathological results:The R0 resection rate of periampullary malignant tumor was 64.3%(77/112),with negative rate of uncinate process margin was 91.1%(102/112). The R0 resection rate of pancreatic ductal adenocarcinoma was 46.9%,with negative rate of uncinate process margin was 89.1%(57/64). Compared with the non-left-sided uncinate process first approach group(222.5(77.0) minutes, 9.2%(14/152)),the left-sided uncinate process first approach group had shorter operation time(246.0(94.0) minutes) (Z=3.964,P<0.01),less intraoperative blood loss (18.8%(22/117))(Z=4.843,P<0.01),and lower intraoperative blood transfusion rate(χ²=5.248,P=0.029). However,there were no significant differences between two groups in postoperative hospital stay(Z=1.682,P=0.093),postoperative overall complications(P=0.549),R0 resection rate of periampullary malignant tumor(χ²=2.012,P=0.156),and negative rate of uncinate process margin(χ²=2.108,P=0.147). Conclusions: The "left-sided uncinate process first approach" could completely resect uncinate process under a direct vision,especially when the uncinate process was behind the superior mesenteric artery or beyond the left lateral margin of the superior mesenteric artery. The "left-sided uncinate process first approach" might increase the negative rate of uncinate process margin and R0 resection rate for periampullary malignant tumor.

[Analysis of risk factors and outcomes for delayed gastric emptying following pancreaticoduodenectomy: a single center experience of 492 cases]

Objective: To evaluate risk factors for delayed gastric emptying(DGE)following pancreaticoduodenectomy(PD). Methods: There were 492 consecutive patients who underwent PD in Pancreas Center, the First Affiliated Hospital with Nanjing Medical University between January 2012 and December 2014 were identified from a prospective database.There were 315 male and 177 female patients with a median age of 60.5 years.Univariate and multivariate analyses were performed to investigate the independent risk factors for clinically relevant DGE(CR-DGE). Results: The overall incidence of DGE was 29.5%, with Grade B and C occurring at 4.3% and 5.9%, respectively.In multivariate analysis, pancreatic duct diameter less than 3 mm(OR=1.888, P=0.042), pylorus-preserving pancreaticoduodenectomy(OR=2.627, P=0.005) and clinically relevant postoperative pancreatic fistula(OR=2.740, P=0.007) were independently associated with CR-DGE.Other main complications such as postoperative pancreatic fistula, pyoperitoneum, intraabdominal infection were also associated with the severity of DGE(χ(2)=21.360, 14.422, 14.378; P=0.011, 0.002, 0.002). DGE patients had a significantly prolonged postoperative length of stay(31(24-41)d vs. 13(11-17)d) and increased medical cost((122 367.5±66 068.3)yuan vs. (78 200.7±27 043.9)yuan)(both P<0.01). Conclusions: Small pancreatic duct, underwent pylorus-preserving pancreaticoduodenectomy and suffered postoperative pancreatic fistula might indicate a high risk of CR-DGE.

[Laparoscopic pancreaticoduodenectomy with a novel artery first and uncinate process first approach through Treitz ligament]

Objective: To explore the clinical effect of a novel artery first and uncinate process first approach for laparoscopic pancreaticoduodenectomy(LPD), emphasizing the left lateral and posterior dissection of uncinate process (UP) via Treitz ligament approach. Methods: From April to November 2016, 18 patients received LPD with a novel approach in Pancreas Center of the First Affiliated Hospital with Nanjing Medical University. All patients were diagnosed as pancreatic head or peri-ampulla tumor, without major vessel invasion nor distant metastasis. For resection, routine caudal view was used in the first step, to dissect the anterior medial border between uncinate process and superior mesenteric vein(SMV). Lymphatic tissues were completely dissected form anterior surface of hepatoduodenal ligament. In the second step, left lateral view with camera from left para-umbilical trocar was used, Treitz ligament was incised, SMA root was exposed. After anticlockwise rotation and retraction of mesentery, the anatomic relationship between SMA trunk, inferior pancreaticoduodenal artery(IPDA), jejunal branch of SMV, and distal part of UP, could be perfectly exposed from left lateral view. SMA was dissected from its root until the position above the uncinate process and duodenum, IPDA was transected, distal part of UP was freed from SMA. In the third step, right lateral view and caudal view were alternatively used; proximal UP mesentery was completely dissected out from SMA root, CA root and posterior surface of hepatoduodenal ligament. Pancreaticoduodenectomy was completed in the forth step after transection of pancreatic neck and common hepatic duct. Results: The SMA root and distal UP were successfully dissected out via Treitz ligament approach in all 18 patients, among them, distal UP was completely excised in 8 patients from left view. Postoperative pathology showed R0 resection rate in 69%. Postoperative complication included intra-abdominal hemorrhage in 1 patient, pancreatic fistula in 7 patients(6 cases with grade A and 1 case with grade B), delayed gastric emptying in 4 patients (2 cases with grade A, 2 cases with grade B). Average postoperative hospital stay was (15.5±6.8)days. Conclusion: The novel artery first and uncinate process first approach through Treitz ligament could help surgeons to completely dissect the full length of meso-pancreas along celiac axis-SMA axis in LPD.

Coronary smooth muscle differentiation from proepicardial cells requires rhoA-mediated actin reorganization and p160 rho-kinase activity

We recently reported that the first detectable expression of SMC-specific proteins during coronary smooth muscle cell (CoSMC) differentiation from isolated proepicardial cells was restricted to cells undergoing epithelial-to-mesenchymal transformation (EMT). The objectives of this study were to examine more closely the relation between actin cytoskeletal rearrangements and serum response factor (SRF)-dependent transcription, and to specifically test whether rhoA-GTPase signaling is required for CoSMC differentiation. We report here that PDGF-BB stimulates EMT and promotes SRF-dependent expression of SMC marker genes calponin, SM22alpha, and SMgamma(actin) (SMgammaA) in proepicardial cells. C3 exoenzyme or rhoGDI, inhibitors of rhoA signaling, blocked PDGF-BB-induced EMT, prevented actin reorganization into stress fibers, and inhibited CoSMC differentiation. Incubation with the selective p160 rho-kinase (p160RhoK) inhibitor Y27632 (RKI) blocked EMT, prevented the appearance of calponin and SMgammaA-positive cells, and abolished expression and nuclear localization of SRF. To test the role of RhoK signaling for CoSMC differentiation in vivo, quail proepicardial organs (PEOs) were pretreated with RKI or vehicle and then grafted into age-matched host chick embryos to produce a chimeric epicardium. The ability of grafted cells to participate in coronary vessel formation was monitored by staining with antibodies for quail cell nuclear antigen and SMC marker proteins. Proepicardial cells pretreated with RKI failed to form CoSMCs in vivo. Time course studies traced this deficiency to a failure of epicardial-derived mesenchymal cells to migrate into or survive within the myocardium. In summary, these data point to important roles for rhoA-RhoK signaling in molecular pathways controlling cytoskeletal reorganization, SRF-dependent transcription, and cell survival that are required to produce CoSMCs from proepicardial cells.

Classification and diagnostic prediction of cancers using gene expression profiling and artificial neural networks

The purpose of this study was to develop a method of classifying cancers to specific diagnostic categories based on their gene expression signatures using artificial neural networks (ANNs). We trained the ANNs using the small, round blue-cell tumors (SRBCTs) as a model. These cancers belong to four distinct diagnostic categories and often present diagnostic dilemmas in clinical practice. The ANNs correctly classified all samples and identified the genes most relevant to the classification. Expression of several of these genes has been reported in SRBCTs, but most have not been associated with these cancers. To test the ability of the trained ANN models to recognize SRBCTs, we analyzed additional blinded samples that were not previously used for the training procedure, and correctly classified them in all cases. This study demonstrates the potential applications of these methods for tumor diagnosis and the identification of candidate targets for therapy.

Glioma cell motility is associated with reduced transcription of proapoptotic and proliferation genes: a cDNA microarray analysis

Microarray analysis of complementary DNA (cDNA) allows large-scale, comparative, gene expression profiling of two different cell populations. This approach has the potential for elucidating the primary transcription events and genetic cascades responsible for increased glioma cell motility in vitro and invasion in vivo. These genetic determinants could become therapeutic targets. We compared cDNA populations of a glioma cell line (G112) exposed or not to a motility-inducing substrate of cell-derived extracellular matrix (ECM) proteins using two sets of cDNA microarrays of 5,700 and 7,000 gene sequences. The data were analyzed considering the level and consistency of differential expression (outliers) and whether genes involved in pathways of motility, apoptosis, and proliferation were differentially expressed when the motility behavior was engaged. Validation of differential expression of selected genes was performed on additional cell lines and human glioblastoma tissue using quantitative RT-PCR. Some genes involved in cell motility, like tenascin C, neuropilin 2, GAP43, PARG1 (an inhibitor of Rho), PLCy, and CD44, were over expressed; other genes, like adducin 3y and integrins, were down regulated in migrating cells. Many key cell cycle components, like cyclin A and B, and proliferation markers, like PCNA, were strongly down regulated on ECM. Interestingly, genes involved in apoptotic cascades, like Bcl-2 and effector caspases, were differentially expressed, suggesting the global down regulation of proapoptotic components in cells exposed to cell-derived ECM. Overall, our findings indicate a reduced proliferative and apoptotic activity of migrating cells. cDNA microarray analysis has the potential for uncovering genes linking the phenotypic aspects of motility, proliferation, and apoptosis.

Homocysteine thiolactone induces apoptotic DNA damage mediated by increased intracellular hydrogen peroxide and caspase 3 activation in HL-60 cells

The cytotoxicity of homocysteine derivatives on chromosomal damage in somatic cells is not well established. The present study used reactive homocysteine derivative of homocysteine thiolactone (Hcy) to investigate its causal effect on apoptotic DNA injury in human promyeloid HL-60 cells. Our results demonstrated that Hcy induced cell death and features of apoptosis including increased phosphotidylserine exposure on the membrane surface, increased apoptotic cells with hypoploid DNA contents, and internucleosomal DNA fragmentation, all of which occurred in a time- and concentration-dependent manner. Hcy treatment also significantly increased intracellular reactive oxygen species H2O2, which coincided with the elimination of caspase 3 proenzyme levels and increased caspase 3 activity at the time of the appearance of apoptotic DNA fragmentation. Preincubation of Hcy-treated HL-60 cells with catalase completely scavenged intracellular H2O2, thus inhibiting caspase 3 activity and protecting cells from apoptotic DNA damage. In contrast, superoxide dismutase failed to inhibit Hcy-induced DNA damage. Taken together, these results demonstrate that Hcy exerted its genotoxic effects on HL-60 cells through an apoptotic pathway, which is mediated by the activation of caspase 3 activity induced by an increase in intracellular hydrogen peroxide.

Folate deficiency induces a cell cycle-specific apoptosis in HepG2 cells

The human hepatoma HepG2 cell line was chosen as a representative of solid tissue-derived cell systems in which folate metabolism and apoptosis induction have not been thoroughly investigated. HepG2 cells were cultivated in the control or folate-deficient media (control media lacking of folate, glycine, thymidine and hypoxanthine) for 4 wk. This resulted in a decrease in intracellular folate levels to 32% of the control within 1 wk, which was followed by growth arrest and greater cell death rates. These disturbances of folate deficiency coincided with apoptotic induction, as characteristically shown by nucleosomal DNA fragmentation of 180-200 base pair multimers, nuclear chromatin condensation and positive terminal transferase-mediated dUTP nick end labeling assay. Apoptosis coincided with an accumulation of cells in S-phase, a subsequent G2/M phase block and a significant increase in mean protein content as evaluated by flow cytometric analyses employing a double-staining method. The growth and cell cycle arrest under folate-deficient conditions was independent of a change of p53 expression as measured by an enzyme-linked immunosorbent assay. Supplementation of 2 micromol/L folate normalized cell cycles and diminished DNA fragmentation. Taken together, these data indicate that HepG2 cells cultivated in folate-deficient medium have a low folate concentration, decreased growth and viability, and increased apoptotic propensity. This occurrence of apoptosis was associated with a cell cycle-specific mechanism and independent of p53-mediated pathway.

Detection of endogenous digitalis-like immunoreactive factors in human blood

Digitalis-like immunoreactive factors (DLIF) are special types of steroids with lactone rings in their structures. Clinically, this type of compound can be used as medicine for heart failure; thus, the elevated endogenous DLIF found under certain pathological conditions are interferent substances in digoxin immunoassay. Endogenous DLIF with biological and immunological properties similar to cardiotonic drugs, such as digoxin, have been found in several tissues and body fluids of animals and humans. Since these endogenous Na+, K(+)-ATPase inhibitors can be considered hormones in nature, immunoassays must be selected detection of them to achieve the required sensitivity and specificity. In this study, we used three sets of in-house formulated immunoassays for DLIF and ouabain-like factors (OLF) detection. Using a polyclonal antibody-based ouabain enzyme immunoassay, the mean +/- S.E.M. of OLF in the sera of 10 healthy individuals were determined to be (9.1 +/- 0.9) x 10(-11) M. Using a monoclonal antibody-based ouabain enzyme immunoassay, the mean +/- S.E.M of OLF in the sera of 10 healthy individuals was (8.2 +/- 1.2) x 10(-11) M while using a antibody fragment Fab-based enzyme immunoassay for digoxin, the mean +/- S.E.M of DLIF in 11 healthy individuals was (4.0 +/- 1.2) x 10(-10) M. In conclusion, our immunological data indicate that DLIFs are normal constituents of human blood. Although DLIF is the major component, coexistence of OLF with DLIF in healthy individuals can not be excluded.

Hemin-induced membrane sulfhydryl oxidation: possible involvement of thiyl radicals

Sublytic levels (microM) of hemin destabilized RBC membrane as indicated by ghost fragmentation pattern using a laser viscodiffractometer. Furthermore, electron microscopic study shows that 5 microM of hemin induced echinocytic transformation whereas higher hemin concentration (40 microM) induced spherocytic transformation. In addition, hemin oxidized sulfhydryl groups in a dose dependent fashion and Electron Spin Resonance study suggests that such oxidation may involve a thiyl radical. Moreover, sulfhydryl compounds enhanced hemin-induced lipid peroxidation. Desferroxamine could prevent hemin-induced sulfhydryl oxidation as well as hemin-induced decrease in membrane stability. In contrast, vitamin E could effectively prevent hemin-induced lipid peroxidation but could not prevent hemin-mediated membrane destabilization.

Purification and characterization of endogenous digoxin-like immunoreactive factors in chicken blood

Studies have been performed to determine whether an endogenous material capable of binding to digoxin antibodies is present in the chicken plasma. In the blood of 12 chickens without feed control, endogenous digoxin-like immunoreactive factors (DLIF) binding of digoxin antibodies in enzyme immunoassays amounted to 866 / 302 pg digoxin equivalents/mL of plasma (mean +/- SEM). Immunoreactivity of DLIF increased to 1848***331 pg/mL with a double value of control after boiling and acid pretreating the plasma. The major purification steps employed in this report were gel filtration column chromatography, high performance liquid chromatography (HPLC) and isoelectric focusing (IEF). Using HPLC for the separation, at least 10 chicken DLIFs with different molecular weight (MW) have been found. The MW of the smallest is 300 daltons (Da) while the largest is 100 kDa. The value of the isoelectric point of the most abundant type of DLIF from untreated chicken plasma is 6.3 as determined by IEF. The partially purified DLIF inhibits Na+, K(+)-ATPase from a porcine cerebral cortex as well as three human red blood cell membrane preparations in a dose-response fashion.

Enhanced vesiculation exacerbates complement-dependent hemolysis in glucose-6-phosphate dehydrogenase deficient red blood cells

Glucose-6-phosphate dehydrogenase (G6PD) deficient red blood cells (RBCs) are known to be more susceptible to oxidant-induced hemolysis. Erythrocytes from G6PD-deficient individuals are significantly more susceptible to Ca(2+)-induced vesiculation than normal control cells. The enhanced susceptibility of G6PD-deficient RBCs to Ca(2+)-induced vesiculation is not due to ATP depletion. The remnant G6PD-deficient RBCs following vesiculation are more sensitive to complement-mediated hemolysis than control normal RBCs. A strong positive correlation exists between the level of Ca(2+)-induced vesiculation and the extent of complement mediated hemolysis.

The effect of decoction of Artemisia, Rheum, and Gardeniae in a piglet model of hyperbilirubinemia

To find an alternative treatment for neonatal hyperbilirubinemia, the effect of a decoction of Artemisia Rheum Gardeniae was tested in an animal model. Fifteen male newborn piglets (four to six days old) were separated into three groups (five piglets/group). The animals of the first group, or Control Group, were intravenously infused with purified bilirubin (40 mg/kg) to simulate neonatal indirect hyperbilirubinemia. The animals of the second and the third groups received the decoction via oral-gastric tube feeding (Enteral Treatment Group) and intravenous injection (Parenteral Treatment Group), respectively, after infusion of bilirubin. Serum bilirubin levels were determined at 0, 0.5, 1, 2, 4 and 8 hours in these groups. The results revealed no significant effect of the decoction on hyperbilirubinemia within eight hours. The implication of this study suggests that a decoction of Artemisia Rheum Gardeniae may be not useful in the treatment of neonatal hyperbilirubinemia.

Correlation of membrane lipid peroxidation with oxidation of hemoglobin variants: possibly related to the rates of hemin release

Experiments were performed to delineate the biochemical mechanism of hemoglobin (Hb)-catalyzed lipid peroxidation in human red blood cells (RBCs). Using a modified Langmuir trough lipid monolayer technique, we found that oxidized Hb induced an increase in lipid monolayer surface pressure, suggesting that oxidized Hb readily releases its heme moiety into the lipid monolayer. To confirm our interpretation that oxidized Hb readily releases its heme moiety, we monitored the fluorescence of Hb tryptophan upon oxidation of Hb. We found an increase in Hb fluorescence in the aqueous phase of our monolayer system after the addition of H2O2. The increase in fluorescence should reflect the departure of heme from globin due to a decrease in fluorescent quenching effect by the heme moiety. The rate of increase in lipid monolayer surface pressure upon Hb oxidation differed from Hb to Hb with an order of Hb E > F > S > A. The ability of various Hbs to affect lipid peroxidation in the RBC membrane, as monitored by the parinaric acid oxidation technique, followed this same order. In addition, hemin was shown to be a more potent catalyst of lipid peroxidation in RBC membrane than nonheme irons.

Detection of a novel lactate dehydrogenase isozyme and an apparent differentiation-associated shift in isozyme profile in hepatoma cell lines

A hitherto unreported lactate dehydrogenase (LD) isoenzyme, which migrates electrophoretically to the relative position between LD2 and LD3 has been identified in the electropheratogram in 7 of 7 (100%) cultured hepatoma cell lines with various degrees of differentiation and is thus given the name LD2-3. LD2-3 seems to be specific for hepatoma cells because this atypical isoenzyme can not be detected in other tumor cell lines. In addition, the hepatoma cell lines also show a distinct pattern of LD isoenzyme and the isoenzyme pattern varies with the degree of differentiation. Hence, the expression pattern of LD isoenzyme phenotypes may provide a good marker for the investigation of human hepatoma cell differentiation.

Sequential liver and bone biochemical changes in hyperthyroidism: prospective controlled follow-up study

OBJECTIVE

To reexamine the prevalence and sequential changes of liver and bone biochemical abnormalities in patients with hyperthyroidism.

METHODS

A consecutive series of 95 patients with hyperthyroidism and 66 controls with euthyroid goiter seen during same period were studied. The patients were treated with propylthiouracil (PTU) 300 mg/day for 2 months, followed by 100-150 mg/day for 3 months and a subsequent maintenance dose of 100 mg/day. Serum aspartate amino-transferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (ALP), gamma-glutamyl transpeptidase (GGT), bilirubin, ALP isoenzymes, and hepatitis markers were studied before therapy and at 2 and 5 months after PTU therapy was begun.

RESULTS

Seventy-two [75.8%, confidence interval (CI) 67.2-84.4%] of the 95 patients had at least one biochemical abnormality. AST, ALT, ALP, GGT, and bilirubin were elevated in 27.4%, 36.8%, 64.2%, 16.8%, and 5.3%, respectively. Of the 34 patients with ALT elevation, 62% showed gradual normalization of ALT, whereas 38% (CI 21.9-54.5%) showed transient, asymptomatic, but significant (p < 0.025) further elevation of ALT during PTU therapy. Overt hepatitis developed in one patient. None of these changes was due to hepatitis A, B, C, or delta virus infection or autoimmune hepatitis. Changes of serum GGT parallel those of ALT. In contrast, serum ALP (primarily bone isoenzyme) rose significantly (p < 0.01) as T4 and T3 levels declined at 2 months after therapy.

CONCLUSIONS

The results suggest that hyperthyroidism is often associated with abnormal biochemical tests, particularly ALP elevation, and thus may pose diagnostic confusion. The increase of bone isoenzyme accounts for the elevations in total ALP level before and during therapy. Serum ALT and GGT abnormalities usually subside during PTU therapy, but transient asymptomatic PTU hepatotoxicity occurs in one-third of the patients. Discontinuation of PTU is not required unless overt hepatitis develops.

Enhanced susceptibility of erythrocytes deficient in glucose-6-phosphate dehydrogenase to alloxan/glutathione-induced decrease in red cell deformability

It has been hypothesized that enhanced oxidant sensitivity of glucose-6-phosphate dehydrogenase (G6PD) deficient red cells(RBCs) is the underlying mechanism for drug- or chemical-induced hemolytic crises in G6PD-deficiency. To further test this hypothesis, we used an alloxan-glutathione system to mimic oxidative stress and see how oxidative damage might affect RBC deformability. RBC deformability, a major determinant of RBC survival in vivo, was monitored by a laser viscodiffractometer. Under our experimental conditions, GSH alone had very little effect on the deformability of either normal or G6PD-deficient RBCs. In contrast, alloxan alone induced a small but significant decrease in the deformability of either normal or G6PD-deficient RBCs. Interestingly, alloxan and GSH together induced a further decrease in the deformability of either normal or G6PD-deficient RBCs. The decrease in deformability in G6PD-deficient RBCs was much more profound than in normal RBCs. In addition, an alloxan-vitamin C system produced a similar deleterious effect on RBC deformability as that produced by the alloxan-GSH system. Appreciable amount of hydroxyl radicals was generated by both alloxan-GSH and alloxan-vitamin C systems as evidenced by the production of hydroxylated products of salicylate which was used as a radical trap. Moreover, salicylate could ameliorate the deleterious effect of the alloxan system on the deformability of RBCs. Taken together, our results demonstrated that G6PD-deficient RBCs were particularly susceptible to oxidant-induced damage leading to a dramatic decrease in their deformability and thus provided strong support for the hypothesis that enhanced oxidant sensitivity of G6PD-deficient RBCs is the underlying mechanism for accelerated destruction of these RBCs in vivo.

High-molecular-mass alkaline phosphatase as a tumor marker for colorectal cancer: comparison of two test methods

We measured high-molecular-mass alkaline phosphatase (HiMwALP) in serum samples from patients with colorectal cancer by polyacrylamide gel electrophoresis (PAGE) and by column chromatography on diethylaminoethyl (DEAE)-cellulose. Determination of carcinoembryonic antigen (CEA) by an enzyme immunoassay, a frequently used cancer assessment method, was used for comparison. We studied patients with primary colorectal cancer (n = 72), using others with hemorrhoids (n = 38) for a comparison group. HiMwALP activities twice those of pooled normal sera were adopted as cutoff values. The diagnostic sensitivity of the PAGE method for 72 colorectal cancer patients was 63% vs 36% for the DEAE method and 50% for the CEA method. The diagnostic specificities of the PAGE, DEAE, and CEA methods were 89%, 79%, and 95%, respectively. Using both HiMwALP (PAGE method) and CEA for the detection of primary colorectal cancer increased the sensitivity to 72% but decreased specificity to 87%.

High-molecular-mass alkaline phosphatase as a tumor marker for colorectal cancer: comparison of two test methods

We measured high-molecular-mass alkaline phosphatase (HiMwALP) in serum samples from patients with colorectal cancer by polyacrylamide gel electrophoresis (PAGE) and by column chromatography on diethylaminoethyl (DEAE)-cellulose. Determination of carcinoembryonic antigen (CEA) by an enzyme immunoassay, a frequently used cancer assessment method, was used for comparison. We studied patients with primary colorectal cancer (n = 72), using others with hemorrhoids (n = 38) for a comparison group. HiMwALP activities twice those of pooled normal sera were adopted as cutoff values. The diagnostic sensitivity of the PAGE method for 72 colorectal cancer patients was 63% vs 36% for the DEAE method and 50% for the CEA method. The diagnostic specificities of the PAGE, DEAE, and CEA methods were 89%, 79%, and 95%, respectively. Using both HiMwALP (PAGE method) and CEA for the detection of primary colorectal cancer increased the sensitivity to 72% but decreased specificity to 87%.

Alkaline phosphatase activity during sphinganine potentiation of retinoic acid-induced differentiation of human promyelocytic leukemia cell line, HL-60

Sphinganine (SP) pre-treatment potentiated the retinoic acid (RA)-induced (4-96h exposures) differentiation and increase of alkaline phosphatase (ALP) activity. A higher percentage of SP pre-treated cells in RA exposures resembled mature myelocytes or granulocytes; greater increase in ALP activity was observed. In cells exposed to RA alone for only a period of 24h, the ALP activity could still increase and reach a similar maximum ALP activity (8.5-10.0 units/mg protein) at 48h as it was under continuous RA treatment. In all cells with longer exposures (24-96h) to RA, SP pre-treatment increased ALP activity to more or less the same higher maximum (14.0-15.5 units/mg protein). SP, added 24h before or concomitantly, but not 24 nor 48h after the addition of RA, could potentiate the RA-induced differentiation and increase of ALP activity.

Apolipoprotein levels in normolipidemic non-insulin-dependent diabetes mellitus

The purpose of this study was to examine the change in apolipoprotein and lipoprotein levels in patients with normolipidemic untreated non-insulin-dependent diabetes mellitus (NIDDM). Fifteen untreated, non-obese male NIDDM patients without hyperlipidemia were chosen, and 15 healthy subjects, matched for age, sex, body weight, alcohol consumption and cigarette smoking served as the control group. We observed that the concentrations of plasma total cholesterol (TC), triacylglycerol (TG) and very low density lipoprotein cholesterol (VLDL-C) were identical in both NIDDM and control groups. The levels of low-density lipoprotein cholesterol (LDL-C) were slightly increased in the diabetic group, but the difference did not reach statistical significance in our study. High-density lipoprotein cholesterol (HDL-C) was lower in the NIDDM group than in the controls. Significantly increased TC/HDL-C and LDL-C/HDL-C ratios were found in NIDDM patients compared with controls. The apolipoprotein A-I (apo A-I) and apolipoprotein A-II (apo A-II) levels were decreased in NIDDM patients, while the apolipoprotein B (apo B) level remained similar to that of the control subjects. The ratio of apo A-I/apo B was decreased significantly in the NIDDM group. Our results suggest that NIDDM patients are at higher risk of coronary heart disease, even if they remain normolipidemic.

Metformin-induced lactic acidosis: report of a case

Lactic acidosis associated with diabetic patients receiving metformin therapy is rare but may cause significant morbidity and mortality. In nearly all reported cases of metformin-associated lactic acidosis, contraindications to its use were noted, especially renal insufficiency. We describe a 59-year-old diabetic man treated with metformin for more than three years. During the third year of use, he experienced progressive renal function impairment, and during the final month of use, he became azotemic. He was maintained on continuous ambulatory peritoneal dialysis. Several days prior to admission, he suffered from epigastralgia, nausea and vomiting, followed by progressive dyspnea which was Kussmaul in nature. Profound hypotension developed and he sank progressively into a coma. Wide-anion gap metabolic acidosis without ketonemia was detected. His blood lactate level was elevated and metformin-induced lactic acidosis was substantiated. An elevated plasma metformin level of greater than 50 mg/mL was determined later by high-performance chromatography. Rigorous treatment including bicarbonate therapy, bicarbonate hemodialysis and vasoactive agents as well as supportive measures were provided. With a return of pH to normal, the hypotension resolved and his consciousness level slowly improved. Our patient survived this disastrous event, but some neurologic sequelae remained. In order to avoid this life-threatening metabolic disturbance, patients with any contraindications should not be prescribed metformin.

Alkaline phosphatase activity during differentiation of the human promyelocytic leukemia cell line, HL-60

The differentiation of HL-60 promyelocytic cells toward mature myelocytic cells induced by retinoic acid (RA) was accompanied by a quantitative similar increase in alkaline phosphatase (ALP) activity. The potentiation of RA-induced differentiation and the enhancement of ALP activity by sphinganine seemed to correlate with each other. The combination of RA and sphinganine increased in parallel the percentage of mature cells and the ALP activities. Short exposures (4-8h) of HL-60 cells to RA promoted differentiation and ALP activity to a fraction (about 50%) of their maximums which were achieved in cells after 24h or longer RA exposure. Our results indicate that the key step for the induction of ALP activity and the differentiation by RA probably takes place within 24h of incubation.

Effect of long-term alcohol ingestion on the femoral head of rabbit

Twenty New Zealand rabbits were chosen for this study (5 for controls and 15 for the alcohol group). In the alcohol group, each rabbit was fed with rice wine (2 g/kg/day alcohol) for 1 year. Bone marrow pressure of the femoral basal neck, erythrocyte sedimentation rate (ESR), liver functions, uric acid, triglyceride, cholesterol, amylase, and blood alcohol level were measured at 0 day, 6 months and 1 year. Finally, the rabbits were sacrificed at the end of the study. The livers and femoral heads were examined for pathology. The bone volume and fat cell size of the femoral head were measured with a computerized "Bone Scanner". The results (1 year comparison) were a significantly higher level of cholesterol in the alcohol group (72 +/- 40 mg% vs 26 +/- 8 mg%, p less than 0.05) and greater bone marrow pressure (27.71 +/- 8.97 mmHg vs 18.20 +/- 4.09 mmHg, p less than 0.05), and no significant difference in triglyceride, uric acid and liver function, ESR, etc., when using Student's 2-tailed t-test. Liver changes (fatty liver) occurred in 3 animals in the alcohol group. The effect of alcohol on the trabecular bone volume was not significant (51.5 +/- 4.6 vol.% vs 50.0 +/- 5.2 vol.%), but the average fat cell size of the femoral head was significantly larger than that for normal controls (2,745 +/- 605 mu2 vs 2,185 +/- 458 mu2, p less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

Rapid laser nephelometric determination of amylase activity in serum and urine

We describe herein a rapid and sensitive laser nephelometric method for the determination of serum and urinary amylase activities. Our data showed that the change in relative light scattering (RLS) of an amylopectin substrate measured by a laser nephelometer related directly with amylolytic activity of amylase from 50 to 600 IU/L. Within-run variations at 293 and 769 IU/L sera showed CV's of 5.0% and 3.1%, respectively. Day-to-day variation for the same sera showed CV's of 7.2% and 4.7%, respectively. Correlation studies using the manual Phadebas dye-starch complex method and with the Roche amylochrome method showed correlation coefficients of 0.99 and 0.95, respectively. Using urine specimens, the correlation studies also showed a correlation coefficient of 0.98. These studies indicated that the proposed method was sensitive, fast, economical and easily adaptable to emergency and routine applications.

Diagnostic efficacy of a monoclonal antibody-based immunoenzymetric technique for quantitation of creatine kinase MB isoenzyme in serum

The clinical usefulness of the Tandem-E CK-MB method (A) using two monoclonal antibodies to measure the intact cardiac specific creatine kinase isoenzyme (CK-MB) was evaluated against results obtained by Corning's electrophoretic fluorescence scanning method (B) and the DuPont aca mechanized column chromatographic method (C). In 95 patients suspected to have myocardial infarction, a total of 127 CK's with MB's were simultaneously determined by methods "A", "B", and "C". "C" produced a total of 16.5% (21 out of 127) false-negative or false-positive results. In contrast, CK-MB results obtained by "A" correlated very well with those determined by "B" (r = 0.97; N = 64). In addition, the clinical course of myocardial infarction as monitored by the measurement of CK-MB at various time intervals by both methods showed excellent parallelism. Furthermore, "A" was shown to be free of interference from the presence of macro CK type I and II. Also, the presence of increasing concentrations of CK-BB (up to 29 IU/L) did not alter the assay response of CK-MB in these serum samples. In conclusion, we found the Tandem-E CK-MB method to be sensitive (sensitivity = 94%) and specific (specificity = 96%).

Quantitative determination of high molecular weight alkaline phosphatase in patients with colorectal cancer by polyacrylamide gel electrophoresis

We present a new method for the quantitative determination of high molecular weight alkaline phosphatase (ALP). This method consists of electrophoretic separation on polyacrylamide, incubation of the ALP isoenzymes with substrate, gel drying and quantitative evaluation by densitometric measurement. This method separates high molecular weight ALP from the other isoenzymes. Precision of the method is calculated by the coefficient of variation ranging from 1.2 to 9.5% for samples with different high molecular weight ALP values. The diagnostic sensitivity for detecting colorectal cancer is 60%.

Simple enzymatic determination of total cholesterol in gallstones

In this simple method for rapid enzymatic determination of total cholesterol in human gallstones, gallstone powder is dissolved in an 80/20 by vol mixture of N,N-dimethylformamide and dimethyl sulfoxide and reacted directly with the aqueous enzymatic reagent, without further treatment. The organic solvents do not interfere with enzymatic activities of cholesterol oxidase, esterase, and peroxidase in the assay mixture. The method is reproducible (CVs 3.7% to 6.6%), analytical recoveries ranged from 98.6% to 102%, and linearity is good. Furthermore, results correlated well with those obtained by infrared spectroscopic measurements.

Simple enzymatic determination of total cholesterol in gallstones

In this simple method for rapid enzymatic determination of total cholesterol in human gallstones, gallstone powder is dissolved in an 80/20 by vol mixture of N,N-dimethylformamide and dimethyl sulfoxide and reacted directly with the aqueous enzymatic reagent, without further treatment. The organic solvents do not interfere with enzymatic activities of cholesterol oxidase, esterase, and peroxidase in the assay mixture. The method is reproducible (CVs 3.7% to 6.6%), analytical recoveries ranged from 98.6% to 102%, and linearity is good. Furthermore, results correlated well with those obtained by infrared spectroscopic measurements.

Biliary alkaline phosphatase measured by mini-column chromatography on DEAE-cellulose: application to detection of hepatobiliary diseases

Using chromatography on diethylaminoethyl (DEAE) cellulose, we measured biliary alkaline phosphatase (BALP; EC 3.1.3.1) activities in sera from 182 patients, most with hepatobiliary disorders but some with non-hepatobiliary diseases. Relative BALP activities were extremely low in otherwise healthy carriers of hepatitis B virus (mean: 5.4 U/L) and in patients with non-hepatobiliary diseases (mean: 5.3 U/L). Although BALP activities were detectable in some cases of liver cirrhosis and chronic hepatitis, these values were generally low (respective means: 12.6 and 12.0 U/L). High BALP activities were detected in patients with primary hepatocellular carcinoma, secondary metastatic liver tumors, and obstructive jaundice: mean values were 27.2, 37.2, and 73.6 U/L, respectively. There was no correlation between BALP activity and bilirubin concentration in patients with obstructive jaundice, nor between BALP activities in obstructive jaundice caused by stones and in those caused by extrahepatic tumor. Some patients with primary hepatocellular carcinoma had high BALP but low alpha-fetoprotein (AFP) values, some others the reverse. Based on AFP alone, the sensitivity for detecting hepatocellular carcinoma was 79%; adding BALP in parallel improved the sensitivity to 97%. We found minicolumn chromatography on DEAE-cellulose useful for determining BALP activity in hepatobiliary diseases.

Biliary alkaline phosphatase measured by mini-column chromatography on DEAE-cellulose: application to detection of hepatobiliary diseases

Using chromatography on diethylaminoethyl (DEAE) cellulose, we measured biliary alkaline phosphatase (BALP; EC 3.1.3.1) activities in sera from 182 patients, most with hepatobiliary disorders but some with non-hepatobiliary diseases. Relative BALP activities were extremely low in otherwise healthy carriers of hepatitis B virus (mean: 5.4 U/L) and in patients with non-hepatobiliary diseases (mean: 5.3 U/L). Although BALP activities were detectable in some cases of liver cirrhosis and chronic hepatitis, these values were generally low (respective means: 12.6 and 12.0 U/L). High BALP activities were detected in patients with primary hepatocellular carcinoma, secondary metastatic liver tumors, and obstructive jaundice: mean values were 27.2, 37.2, and 73.6 U/L, respectively. There was no correlation between BALP activity and bilirubin concentration in patients with obstructive jaundice, nor between BALP activities in obstructive jaundice caused by stones and in those caused by extrahepatic tumor. Some patients with primary hepatocellular carcinoma had high BALP but low alpha-fetoprotein (AFP) values, some others the reverse. Based on AFP alone, the sensitivity for detecting hepatocellular carcinoma was 79%; adding BALP in parallel improved the sensitivity to 97%. We found minicolumn chromatography on DEAE-cellulose useful for determining BALP activity in hepatobiliary diseases.

The effect of vitamin B2 and its derivatives on a dry-reagent strip theophylline assay

This report describes the effect of flavin adenine dinucleotide (FAD) and its precursor vitamin B2 on an apoenzyme reactivation immunoassay system (ARIS) both in vitro and in vivo. It was observed that 10 nM/L FAD in the buffer causes a false-positive result in ARIS for theophylline by the value of 94 microM/L, whereas vitamin B2, flavin mononucleotide, adenosine, adenosine monophosphate, and adenosine diphosphate (ADP) at the same concentration caused no such effect. Nevertheless, ADP at 2 microM/L can cause a drop in theophylline reading of 55 microM/L. However, the sera from four volunteers with normal liver functions who had taken 30 mg of vitamin B2 daily for a week showed no effect on theophylline reading.

Substrate selectivity of squalene synthetase

Six 1-3H-labeled analogues of farnesyl pyrophosphate have been studied as potential substrates for yeast and rat liver squalene synthetases: 2-methylfarnesyl pyrophosphate (4), 3-demethylfarnesyl pyrophosphate (5), 7,11-dimethyl-3-ethyl-2,6,10-dodecatrienyl pyrophosphate (6), 6,7,10,11-tetrahydrofarnesyl pyrophosphate (7), 4-methylthiofarnesyl pyrophosphate (8), and 4-fluorofarnesyl pyrophosphate (9). Analogues 4 and 5 are enzymatically incorporated into 11-methylsqualene (10) and 10-demethylsqualene (11), respectively, even if no farnesyl pyrophosphate is added to the incubations. None of the other analogues gives nonpolar products with either the yeast or liver enzymes. No tritium is enzymatically released to the medium from any of the analogues, indicating that they are not accepted at the first (proton exchanging) site. The data rule out formation of dead-end presqualene pyrophosphate products with analogues as first, but not as second, substrates. Implications of these results for the enzyme active-site topology and mechanism are discussed.

Inhibition of squalene synthetase by farnesyl pyrophosphate analogues

The pyrophosphates of the following farnesol analogues have been synthesized: 2-methylfarnesol; 7,11-dimethyl-3-ethyl-2,6,10-dodecatrien-1-ol; 3-demethylfarnesol; 4-methylthiofarnesol; 7,11-dimethyl-3-iodo-2,6,10-dodecatrien-1-ol; 7,11-dimethyl02-iodo-2,6,10-dodecatrien-1-ol; 7,11-dimethyldodeca-6,10-dien-2-yn-1-ol; phytol; 3,7,11-trimethyl-2-dodecen-1-ol; 3,7,11-trimethyldodecan-1-ol; and geraniol. The double bonds in all the above compounds were in the E configuration, except phytol, which was a 7:3 mixture of 2E and 2Z isomers. Each of the pyrophosphates inhibits the incorporation of labeled farnesyl pyrophosphate into squalene by a yeast enzyme preparation. Free alcohols and monophosphates are inactive. The analogues, listed in order of decreasing inhibitory strength, are, by kinetic analysis, competitive or mixed inhibitors. Irreversible inhibition is not observed. The results suggest that binding to the enzyme is primarily mediated by the pyrophosphate moiety assisted by relatively nonspecific lipophilic interactions. Decreasing the chain length and saturating double bonds severely reduces binding, while substitution at the 2,3, and 4 positions, and lengthening of the chain, is well tolerated.