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T L Hwang

Publications and source records attributed to T L Hwang.

At least 19 recordsLinked to original sources
PubMed2005

Selective cytotoxicity of azatyrosinamides against ras-transformed NIH 3T3 cells.

This study aims to develop novel azatyrosinamide compounds structurally modified from ras-specific antioncogenic azatyrosine. Analogues 4-15 were prepared and their inhibition on the growth of wild-type and ras-transformed NIH 3T3 cell lines was compared. Compound 12 was found to be the most active with IC50 16.5+/-2.2 microM which is 458-fold more potent than that of azatyrosine. The selective toxicity, defined as IC(50 wild-type)/IC(50 ras-transformed) for this compound was 138.5.

Alanine↗
PubMed2001

Inhibition of the expression of inducible nitric oxide synthase and cyclooxygenase-2 in macrophages by 7HQ derivatives: involvement of IkappaB-alpha stabilization.

Nitric oxide is an important biological mediator associated with multiple pathophysiological phenomena, such as platelet aggregation, vasodilation, septic shock, and autoimmune diseases. Prostaglandins, derived from cyclooxygenases, play prominent roles in homeostasis and inflammation. In this study, we characterized the effects of 7HQ derivatives (7-[(4-methylene-5-oxo-2-R-2-tetrahydrofuranyl) methoxy]-3,4-dihydrocarbostyril, where R is methyl, phenyl, p-fluorophenyl and p-phenylphenyl; 7HQ-1,-2,-3 and-4, respectively) in murine RAW 264.7 cells, a macrophage-like cell line. Lipopolysaccharide, the active component of endotoxin, significantly induced the expression of inducible nitric oxide synthase and cyclooxygenase-2, leading to the accumulation of nitrite and prostaglandin E(2), respectively. These actions of lipopolysaccharide were inhibited by 7HQ derivatives; additionally, the inhibition of the expression, rather than the activity, of inducible nitric oxide synthase correlated well with that of nitric oxide formation. Western blotting and electrophoretic mobility shift assay results demonstrated that the 7HQ derivatives could effectively inhibit IkappaB-alpha degradation and nuclear factor kappaB (NF-kappaB) translocation. At higher concentrations, 7HQ derivatives also inhibited cyclooxygenase-2 enzyme activity. These results suggest that 7HQ derivatives exhibit inhibitory effects on lipopolysaccharide-induced nitric oxide production and expression of inducible nitric oxide synthase and cyclooxygenase-2 through inhibition of IkappaB-alpha degradation and NF-kappaB activation.

Animals↗
PubMed2001

Inhibitory effect of DCDC on lipopolysaccharide-induced nitric oxide synthesis in RAW 264.7 cells.

In the present study we have examined the effect of DCDC (2',5'-dihydroxy-4-chloro-dihydrochalcone) on lipopolysaccharide (LPS)-induced responses in murine macrophage cell line RAW 264.7. Exposure of LPS-stimulated cells to DCDC inhibited the nitrite accumulation in culture medium. DCDC also concentration-dependently inhibited LPS-stimulated increase of iNOS expression; however, it had little effect on iNOS enzyme activity, suggesting that the inhibitory action to DCDC is mainly due to the inhibition on iNOS expression rather than iNOS enzyme activity. DCDC significantly inhibited LPS-evoked degradation of IkappaB-alpha and the nuclear translocation of NF-kappaB; it also exhibited the activity of scavenging the stable free radical 1,1-diphenyl-2-picrylhydrazyl (DPPH). DCDC also inhibited cyclooxygenase-2 activity in RAW 264.7 cells with an IC50 of 3.0 microM; furthermore, it also significantly decreased LPS-induced mortality rate in mice. Taken together, we demonstrate that DCDC exhibits inhibitory effects on nitric oxide production through the inhibition of IkappaB-alpha degradation and NF-kappaB activation, and therefore the suppression of iNOS expression. DCDC also shows the antioxidant activity and COX-2 inhibitory action. Moreover, it improves survival in a murine model of endotoxaemia suggesting that DCDC may be potential in the therapy of septic shock.

Animals↗
PubMed2001

Parenteral nutrition support after bone marrow transplantation: comparison of total and partial parenteral nutrition during the early posttransplantation period.

OBJECTIVE: Bone marrow transplantation (BMT) usually is indicated if the patient's malignant disease involves the marrow or if hazard to the normal marrow is the limiting factor in the aggressive treatment of disease. The success of BMT depends on a complete team with all the resources needed to ensure optimal results. Aggressive nutrition support after BMT is very important. Adequate parenteral nutrition, total (TPN) or partial, followed by enteral nutrition according to the patient's gastrointestinal function is the important principle. METHODS: Between 1996 and 2000, 60 patients, 46 male and 14 female, received BMT in Chang Gung Memorial Hospital. Their ages ranged from 6 to 54 y. Standard TPN was used in 40 patients after BMT, and partial parenteral nutrition was used in the remaining 20 patients. TPN was enriched with branched-chain amino acids (BCAA) when the patient's liver functions were impaired, and cyclic TPN was shifted when the patient's liver functions persistently deteriorated. RESULTS: Most patients improved their nutrition status and increased their body weights, especially those receiving TPN. The patients receiving partial parenteral nutrition decreased their visceral proteins significantly during the course of parenteral nutrition. The BCAA-TPN can maintain a patient's visceral protein better than standard TPN. Only two patients expired because of graft rejection and sepsis; their body weights and nutrition status showed deterioration despite aggressive nutrition support. CONCLUSIONS: We conclude that the nutrition support for patients with BMT is related to the success of marrow transplantation. Parenteral nutrition support, especially with TPN, is important because of frequent gastrointestinal dysfunction during the posttransplantational period, and it is better at maintaining the nutrition status and body weights of patients after BMT. An oral diet can be resumed after the patient's gastrointestinal function has improved and it can be tolerated.

Adolescent↗
PubMed2001

Human progesterone receptor shows differential sensitivity to carboxyl group modifying agents when bound to agonist and antagonist ligands.

BACKGROUND: Modulation of human uterine progesterone receptor (PR) in relation to its binding to synthetic steroids with known agonist (R5020) and antagonist (triamcinolone acetonide, T.A.) properties was studied in the presence of the specific carboxyl group modifiers, N,N'-dicyclohexylcarbodiimide (DCCD) and 1-ethyl-3-carbodiimide hydrochloride (EDC). METHODS: Uterine cytosol was treated with DCCD or EDC. The amounts of total bound were detected using the steroid binding measurements. The formation and transformation of progesterone-receptor complexes (PRc) were analyzed using sedimentation rate analysis. RESULTS: Our studies show that the modification of the COOH group differentially influences the properties of mammalian PR binding with either R5020 or T.A. DCCD and EDC affect the steroid binding of PR by decreasing the binding sites, not by the changing the affinity. CONCLUSION: Our studies indicate the importance of the carboxyl group in steroid binding by PR. This implies that both aspartic acid and glutamic acid residues, which have the carboxyl group, may play an important role when PR binds with steroid ligands.

Cytosol↗
PubMed2000

Contrast-enhanced dynamic computed tomography does not aggravate the clinical severity of patients with severe acute pancreatitis: reevaluation of the effect of intravenous contrast medium on the severity of acute pancreatitis.

BACKGROUND: Contrast-enhanced abdominal computed tomography (CT) is useful in demonstrating pancreatitis necrosis, but the administration of contrast medium in animal models with acute pancreatitis may worsen the severity. HYPOTHESIS: The use of contrast-enhanced CT in clinical patients with acute pancreatitis may actually aggravate the severity of the disease. DESIGN: A randomized prospective study. SETTING: Chang Gung Memorial Hospital, Taipei, Taiwan. PATIENTS: Twenty patients with severe acute pancreatitis were randomly divided into 2 groups. Those in group A (n = 10) underwent a CT examination with a contrast-enhanced medium, and those in group B (n = 10) underwent a CT examination without a contrast-enhanced medium. MAIN OUTCOME MEASURES: The patients' serum amylase, lipase, C-reactive protein, leukocyte, glutamicoxaloacetic transaminase, creatinine, calcium, and phosphate levels were serially checked before the CT examination and at 2, 4, 6, 8, 12, and 24 hours after the examination was performed. The biochemical data between the 2 groups were compared. The morbidity, length of stay, and mortality were also compared. RESULTS: There were no significant changes in the level of pancreatic enzymes, C-reactive proteins, and leukocytes and in the biochemical data of either group before or after the CT examination. The difference in the previously examined values between the 2 groups was also not significant. There was also no difference in the morbidity, length of hospital stay, and mortality between the 2 groups. CONCLUSION: Contrast-enhanced abdominal CT does not aggravate the severity of clinical patients with severe acute pancreatitis.

Adult↗
PubMed2000

Pharmacological characterization of EK112, a new combined angiotensin II and thromboxane A(2) receptor antagonist.

The pharmacological characterization of EK112, a new combined angiotensin II and thromboxane A(2) receptor blocking agent, was examined in this study. EK112 was found to be a angiotensin II receptor antagonist, as revealed by its competitive antagonism of angiotensin II-induced smooth muscle contraction (pA(2) value of 7. 63 +/- 0.14) in rabbit aorta. It also had an angiotensin II blocking action in guinea pig ileum (pA(2) value of 7.87 +/- 0.67). Additionally, EK112 also possessed thromboxane A(2) receptor blocking activity, since it competitively antagonized aortic contractile responses elicited by U46619 and PGF(2alpha)(pK(B) values of 6.67 +/- 0.09 and 6.24 +/- 0.09, respectively) in rat. In contrast, EK112 did not affect the contractile responses to many other receptor agonists. EK112 did not mimic that of the angiotensin-converting enzyme (ACE) inhibitor, captopril, to enhance the muscle contraction elicited by bradykinin in guinea pig ileum, suggesting that EK112 did not inhibit ACE. Neither cyclic AMP nor cyclic GMP content in rat aortic rings was changed by EK112. These data demonstrate that EK112 is a selective antagonist of angiotensin II > thromboxane A(2) thromboxane A(2) receptor.

Angiotensin II↗
PubMed2000

Impact of concomitant hepatolithiasis on patients with peripheral cholangiocarcinoma.

The association of hepatolithiasis (HL) and peripheral cholangiocarcinoma (PCC) has been well recognized. However, information concerning the impact of hepatolithiasis on patients with peripheral cholangiocarcinoma is sparse and therefore difficult to assess. A total of 162 consecutive patients with histologically proven peripheral cholangiocarcinoma were treated surgically at Chang-Gung Memorial Hospital between 1977 and 1994. Among them, 106 patients (65.4%) had associated hepatolithiasis (PCC + HL group), and the remaining 56 patients (34.6%) did not (the PCC - HL group). The differences in demographics, symptomatology, laboratory data, tumor staging, histological pattern, resectability rates, and long-term survival of these two groups were compared. The male to female ratio was 0.7 in the PCC + HL group and 1.3 in the PCC - HL group (P < 0.05). Two thirds of the PCC + HL group presented with acute cholangitis, whereas two thirds of the PCC - HL group presented with hepatomegaly (P < 0.01). Those patients in the PCC + HL group were in earlier stages than those of the PCC - HL group at the time of the initial diagnosis (P < 0.05). The resectability rate for the PCC + HL group was 31.1% and for the PCC - HL group, 26.8% (P > 0.05). Surgical mortality rates were 3.8% in the PCC + HL group and 3.6% in the PCC - HL group (P > 0.05). The morbidity rate was much higher in the PCC + HL group than in the PCC - HL group (P < 0.01). The 1-, 3-, and 5-year survival rates were 35.5%, 20.5%, and 16.5% in the PCC + HL group and 27.2%, 8.8%, and 7.8% in the PCC - HL group (P > 0.05). In conclusion, the presence of hepatolithiasis hindered an exact diagnosis of underlying cholangiocarcinoma preoperatively, precipitated biliary sepsis which affected resectability, and increased postoperative morbidity. Hepatolithiasis per se, however, did not influence the long-term survival.

Adult↗
PubMed2000

YD-3, a novel inhibitor of protease-induced platelet activation.

1. In the present study, the antiplatelet effects and mechanisms of a new synthetic compound YD-3 [1-benzyl-3(ethoxycarbonylphenyl)-indazole] were examined. 2. YD-3 inhibited the aggregation of washed rabbit platelets caused by thrombin (IC(50)=28.3 microM), but had no or little inhibitory effect on that induced by arachidonic acid, collagen, platelet-activating factor (PAF) or U46619. YD-3 also suppressed generation of inositol phosphates caused by thrombin. On the other hand, thrombin-induced fibrin formation was not affected by YD-3, indicating YD-3 does not inhibit the proteolytic activity of thrombin. 3. In washed human platelets, however, YD-3 had only mild inhibitory effect on the low concentration (0.05 u ml(-1)) of thrombin-induced human platelet aggregation, and did not affect that induced by higher concentrations (> or =0.1 u ml(-1)) of thrombin or SFLLRN, the protease-activated receptor 1 (PAR1) agonist peptide. By contrast, YD-3 inhibited both human and rabbit platelet aggregation elicited by trypsin with IC(50) values of 38.1 microM and 5.7 microM, respectively. 4. YD-3, at 100 microM, had no effect on ristocetin-induced glycoprotein Ib (GPIb)-dependent aggregation of human platelets. In addition, platelets treated with chymotrypsin, which cleaves GPIb, enhanced rather than attenuated the inhibition of YD-3 on thrombin-induced human platelet aggregation. These data indicate that GPIb plays no role in the antiplatelet effect of YD-3. 5. In SFLLRN-desensitized human platelets, high concentration of thrombin (1 u ml(-1)) could still elicit intracellular Ca(2+) mobilization, and the rise of [Ca(2+)](i) was prevented by either leupeptin or YD-3. 6. Our results suggest that YD-3 inhibits a non-PAR1 thrombin receptor which mediates the major effect of thrombin in rabbit platelets, but in human platelets, this receptor function becomes significant only when the function of PAR1 has been blocked or attenuated.

Animals↗
PubMed2000

Malignant perihilar biliary obstruction: magnetic resonance cholangiopancreatographic findings.

OBJECTIVE: We studied the efficacy of magnetic resonance cholangiopancreatography (MRCP) in the evaluation of malignant perihilar biliary obstructions, with reference to endoscopic retrograde cholangiopancreatography (ERCP). METHODS: A total of 40 patients with malignant perihilar biliary obstructions, who underwent both MRCP (Magnetom Vision; Siemens, Erlangen, Germany; projection technique and multislice plus maximum intensity projection) and ERCP examinations, were studied. The study group included hilar cholangiocarcinoma (Klatskin tumor) in 26 patients, icteric hepatocellular carcinoma in four patients, gallbladder carcinoma in five patients, and metastasis from other than hepatobiliary origin in five patients. Axial and coronal magnetic resonance (MR) images were added simultaneously to the MRCP. The mean serum bilirubin level on admission was 11.5 mg/ml (range, 2.8-28.5 mg/ml). The presence and extent of malignant biliary obstruction were determined with both MRCP and ERCP following the known criteria: an abrupt and irregular character of a distal narrow segment, a proportionally dilated biliary tree proximally, and an irregularly shaped intraluminal filling defect. The efficacy of the MRCP examination in detecting the presence of biliary obstruction, its anatomical extent, and the underlying cause, respectively, was compared to that of ERCP. RESULTS: MRCP examination was successfully performed on all patients, whereas ERCP examination was unsuccessful in two patients. Both MRCP and ERCP were very effective in detecting the presence of biliary obstructions (40 of 40 vs. 38 of 38, p = 1.0). MRCP was superior in its investigation of anatomical extent (34 of 40 vs. 24 of 38, p = 0.015) and the cause of the jaundice (31 of 40 vs. 22 of 38, p = 0.023) compared to ERCP. Specifically, the performance of MRCP is promising for the interpretation of cholangiocarcinoma (22 of 26) and gallbladder carcinoma (five of five), but is relatively ineffective for the interpretation of icteric HCC (two of four) and metastasis (two of five). CONCLUSION: MRCP represented an ideal noninvasive diagnostic tool for the evaluation of malignant perihilar biliary obstructions with reference to ERCP.

Bile Duct Neoplasms↗
PubMed1999

Asymmetric adiabatic pulses for NH selection.

Many types of NMR experiments demand the use of frequency-selective pulses to invert magnetization within discrete frequency limits. For certain experiments, only one side of the inversion band must be sharply demarcated, in which case this transition bandwidth can be narrowed when using an asymmetric adiabatic full passage. In the present study, a highly efficient asymmetric adiabatic full passage was created from a combination of two adiabatic half passages which used different modulation functions (HS12 and tanh/tan). Each adiabatic half passage occupied a different amount of time in the total pulse and performed one-half of the inversion. On one side, HS12 produced a sharp transition between inverted and noninverted states which was approximately 2.5 times narrower than the transition bandwidth afforded by a symmetric hyperbolic secant pulse of equal length. On the other side of the narrow transition band, the tanh/tan pulse achieved broadband inversion. These asymmetric pulses were applied to select NH groups immediately adjacent to the water signal in water-flip-back HSQC experiments using a double spin echo for the reverse INEPT step.

Fourier Analysis↗
PubMed1999

Telomerase activity is a useful marker to distinguish malignant pancreatic cystic tumors from benign neoplasms and pseudocysts.

BACKGROUND: Pancreatic serous cystadenoma, mucinous cystic neoplasms, ductal adenocarcinoma with cystic change, and pseudocysts are a spectrum of pancreatic cystic lesions. Their management strategy and prognosis are extremely diverse. Imaging study, cytology, and analysis of the tumor markers of cyst fluid are not always reliable in differentiation of these disease entities. MATERIALS AND METHODS: Fifteen patients with pancreatic cystic neoplasms (including six mucinous cystadenocarcinomas, two mucinous cystic neoplasms with borderline malignancy, two mucinous cystadenomas, and five serous cystadenomas), 4 patients with pancreatic ductal adenocarcinomas with cystic change, and 10 patients with pseudocysts were studied. Echo-guided or computed tomography-guided biopsies of pancreatic cystic lesions and their normal counterparts were conducted on all patients prior to operation or other management. The specimens were assayed for telomerase activity by using TRAP (telomere repeat amplification protocol). The level of telomerase activity in each specimen was semiquantitated as strong, moderate, weak, and none. The final diagnoses were made from histopathological examination of surgically resected or biopsied specimens. The efficacy of telomerase activity as a tumor marker to predict malignancy of pancreatic cystic lesions was evaluated. RESULTS: Three of the four pancreatic ductal adenocarcinomas with cystic change had strong or moderate telomerase activity; four of the six mucinous cystadenocarcinomas had moderate or weak telomerase activity; one of the two mucinous cystadenomas with borderline malignancy had weak telomerase activity; and none of their normal counterparts had detectable telomerase activity. In contrast, none of the two mucinous cystadenomas, five serous cystadenomas, and 10 pseudocysts had detectable telomerase activity. Based on these results, the sensitivity of telomerase activity for prediction of malignancy or premalignancy of pancreatic cystic lesions was 67%, the specificity was 100%, and the positive and negative predictive values were 1.0 and 0.81, respectively. The overall accuracy was 86%. CONCLUSIONS: The differential expressions of telomerase activity have been detected specifically in malignant and premalignant pancreatic cystic tumors, but not in benign cystic neoplasms or pseudocysts. The implications of these results are that telomerase activation takes part in the malignant transformation of pancreatic cystic neoplasms and that telomerase activity is a useful marker to distinguish malignant pancreatic cystic tumors from benign neoplasms and pseudocysts.

Adult↗
PubMed1999

Intrahepatic cholangiocarcinoma in Taiwan.

We report our experience of the surgical treatment of intrahepatic cholangiocarcinoma (ICC) in Taiwanese patients. A total of 162 patients with histologically proven ICC were treated of whom 106 (65. 4%) had associated hepatolithiasis. Patients with hepatolithiasis were in earlier stages than those without hepatolithiasis. Two-thirds of the patients with hepatolithiasis presented with acute cholangitis, and two-thirds of those without hepatolithiasis presented with hepatomegaly. The rate of hepatic resection was 29.6% (48 of 162), and these rates were 31.1% and 26.8% for the patients with and without hepatolithiasis, respectively. Ninety-three percent of the patients with hepatolithiasis underwent common bile duct exploration, compared with 18% of those without hepatolithiasis. The surgical mortality rates were 3.7% (6/162), for all patients, and 3. 8% and 3.6% for patients with and without hepatolithiasis, respectively. The morbidity rate was much higher in the patients with hepatolithiasis (37.7% vs 16.1%). The 1-, 3-, and 5-year survival rates were 35.5%, 20.5%, and 16.5% in the patients with hepatolithiasis and 27.2%, 8.8%, and 7.8% in those without hepatolithiasis. Concomitant hepatolithiasis prevented precise diagnosis preoperatively and precipitated biliary sepsis, which affected resectability and increased postoperative morbidity. Hepatolithiasis per se did not influence long-term survival.

Adult↗
PubMed1999

Microvascular prefabricated free skin flaps for esophageal reconstruction in difficult patients.

BACKGROUND: Reconstruction of the esophagus for complicated benign stricture or after resection of malignant lesion is still a challenge for surgeons. When abdominal viscera cannot be used, skin flaps are selected for esophageal reconstruction. However, skin flaps for esophageal reconstruction are notorious for leakage, and have not been widely accepted. Prefabrication before microvascular transfer to its final site can improve the result of esophageal reconstruction when skin flaps are used. METHODS: Eight patients with complicated corrosive esophagitis had been treated with prefabricated skin flaps for esophageal reconstruction. The procedures are described in detail. RESULTS: All patients healed well without leakage. The barium study showed smooth passage. There was no dysphasia or regurgitation after education. Pulmonary complication happened in only 1 patient. Revision for the distal anastomosis was required in 1 patient due to narrowing. When the skin tube is long, the patients need water (or soup) to facilitate swallowing and occasionally use their hand to help the food passage. This method has the following advantages: (1) healing of the long suture line before transfer to withstand the intestinal juice; (2) reliable viability in the distal part of the flap, especially when an extended length of the flap is required; (3) more length of stable tissue for two-layered, tension-free anastomosis at the junction of skin and gastrointestinal mucosa to prevent leakage; and (4) the flap can be placed in the substernal position to meet the aesthetic requirement of young patients. The disadvantage was the staged operations. However, after prefabrication the transfer becomes safe and free of leakage. The overall morbidity is minimal. CONCLUSIONS: In rare situations when skin flaps are used for esophageal reconstruction, prefabrication provides advantages over conventional one-stage methods, although it needs additional procedures. This method is a combination of conventional technique and microsurgery.

Adult↗
PubMed1999

YC-1 potentiates nitric oxide-induced relaxation in guinea-pig trachea.

1. The effects of YC-1 (3-(5'-hydroxymethyl-2'-furyl)-1-benzylindazole) on tension, levels of cyclic GMP and cyclic AMP were investigated in guinea-pig trachea. We especially studied the combined effect of YC-1 with exogenous or endogenous nitric oxide on these parameters. 2. YC-1 at the concentration 3 or 10 microM, which caused only minor effect by itself, elicited concentration-dependent potentiation of sodium nitroprusside (SNP)-induced tracheal relaxation. This relaxation of YC-1 with SNP was reversed by ODQ. 3. Relaxant responses to electric field stimulation (EFS) in the presence of indomethacin, atropine, guanethidine, alpha-chymotrypsin and histamine were also markedly increased by YC-1 (10 microM). In the presence of L-NAME or ODQ, the relaxant effects to EFS were attenuated and the following addition of YC-1 did not further enhance relaxation. 4. YC-1 (10 microM) or SNP (0.3 microM) alone did not induce significant elevation of cyclic GMP levels in the presence of IBMX, whereas simultaneous application of both compounds markedly elevated the cyclic GMP accumulation. In contrast, the cyclic AMP levels were not altered even at the combination of YC-1 and SNP. Additionally, YC-1 also affected cyclic GMP metabolism, since it inhibited the activity of phosphodiesterase type V in human platelets. 5. YC-1 (30 microM) did not scavenge superoxide anion and had no effect on the removal of superoxide anion by superoxide dismutase in a xanthine/xanthine oxidase system. 6. In conclusion, these results indicate that although YC-1 elicits negligible relaxation of guinea-pig trachea by itself, it can potentiate the relaxant responses of exogenous or endogenous NO. This synergistic response of YC-1 is via the elevation of cyclic GMP contents.

Animals↗
PubMed1999

Value of magnetic resonance cholangiopancreatography in demonstrating major bile duct injuries following laparoscopic cholecystectomy.

BACKGROUND: Conventionally, recognition of bile duct injuries after laparoscopic cholecystectomy largely relies on endoscopic retrograde cholangiopancreatography (ERCP) and percutaneous transhepatic cholangiography (PTC). However, these invasive procedures are not without risk. Preliminary experience with use of magnetic resonance cholangiopancreatography (MRCP) to identify these injuries is reported. METHODS: The medical records of five patients who had undergone laparoscopic cholecystectomy and had suspected major bile duct injuries were reviewed. All five patients underwent MRCP, followed by conventional cholangiography: either ERCP or PTC, or both. The findings of MRCP and conventional cholangiography were compared. RESULTS: Four patients had proven bile duct injuries. The remaining patient had gallstones dislodged into the common bile duct (CBD) during laparoscopic cholecystectomy, which presented as transient jaundice mimicking a bile duct injury. The MRCP images were of higher diagnostic value than conventional cholangiographic images in four patients with frank bile duct injury. For these patients, ERCP showed only the cut-off sign of the CBD, and PTC was needed to visualize the upper biliary system. MRCP, however, demonstrated the entire biliary system proximal and distal to the amputated or stenotic sites simultaneously. In the remaining patient with dislodged gallstones, the two techniques yielded similar diagnostic information. CONCLUSION: This preliminary study suggests that MRCP is an ideal diagnostic test whenever bile duct injury following laparoscopic cholecystectomy is suspected.

Adult↗
PubMed1999

Arginine-nitric oxide pathway in plasma membrane of rat hepatocytes during early and late sepsis.

OBJECTIVE: To study the transported L-arginine in rat hepatocytes during different stages of sepsis. DESIGN: A prospective, controlled study. SUBJECTS: Thirty-six Sprague-Dawley male rats (250 to 300 g) were anesthetized and studied. INTERVENTIONS: Early sepsis was produced 9 hrs after cecal ligation and puncture (CLP) and late sepsis developed 18 hrs after CLP. The control group underwent sham operation. Plasma membrane of rat hepatocytes was prepared by differential centrifugation. The [3H] L-arginine uptake of plasma membrane vesicles during sepsis was measured and inhibition studies employing omega-nitro-L-arginine methyl ester (L-NAME) and aminoguanidine were performed. MEASUREMENTS AND MAIN RESULTS: L-arginine transport was saturable, increased linearly with plasma membrane protein concentration, and increased with uptake time up to 5 mins. [3H] L-arginine uptake increased by 77% to 121% (p < .05) during early sepsis, with no significant changes during late sepsis. Comparing inhibitors of nitric oxide synthase, L-NAME was effective in inhibiting L-arginine transport while aminoguanidine was not. CONCLUSIONS: L-arginine transport was enhanced in rat hepatocytes during the early stage of sepsis. The increased uptake of L-arginine could contribute to the increase production of nitric oxide by hepatocyte during sepsis.

Animals↗