Studies on conotoxins of Conus betulinus

The biological activity and toxicity of crude venom from Conus betulinus, which was collected from the South China Sea, were studied. The venom shows Ach receptor activity, K+ current effect, and low toxicity. Four peptide components, named BeTXIa, BeTXIb, BeTXIIa, and BeTXIIb, were purified by gel-filtration with Sephadex followed by HPLC, and finally sequenced on an ABI model 491 sequencer. The low-molecular-weight peptides BeTXIa and b have 14 and 15 amino acid residues, respectively, while BeTXIIa and b have 27 and 30 amino acid residues, respectively. The results indicate that BeTXs from the venom of C. betulinus are a set of small peptides with a high cysteine content like known conotoxins. However, it is meaningful to find that these sequences have specific chemical characteristics in their cysteine framework which differ greatly from known cysteine frameworks in conotoxin structures.

Revascularization of turnover sternum: A definitive treatment for intractable funnel chest

Twelve intractable funnel chests in young adults were treated with revascularization of the turnover sternum. The sternum and costal composite tissue were resected at the outskirt of the depressed area. Special attention was paid to the dissection of the vascular pedicle at both sides of the internal mammary vessels. The recipient vessels at one side were left long, so were the donor vessels at the other side. A segment of the rib at the exit of the recipient internal mammary vessels had to be removed to accommodate the vessels and to facilitate vascular anastomosis. Vascular anastomosis was accomplished with loupes (Keeler, sixfold magnification) in five patients because the direction of the vessels is vertically oriented. In four cases, artery and vein grafts were taken from the other side of the internal mammary vessels not bound for vascular anastomosis for length discrepancy of the vessels, while the remaining cases had direct vascular anastomosis without vascular grafting. Revascularization of the turnover sternum was performed successfully without vascular compromise. The patients all recovered well with much improved physical condition. Only one patient sustained spontaneous pneumothorax 1 month after the operation. Postoperative three-dimensional computed tomographic (CT) scan revealed increment of thoracic cage volume for 9-17%. Follow-up CT scan 2 years later revealed even more improved thoracic cage expansion.

Significance of P53 and Rb protein expression in surgically treated non-small cell lung cancers

BACKGROUND

Alterations of the P53 or Rb gene are among the most frequently observed genetic changes in primary lung cancer. Nevertheless, there has been no final conclusion on the relationship between P53 or Rb protein expression and clinico-pathological parameters in primary lung cancer. A large-scale study was performed to examine the clinicopathological and prognostic significance of P53 and Rb expressions in 207 surgically resected non-small cell lung cancer (NSCLC) patients.

METHODS

Tumor specimens were obtained from 207 primary NSCLC surgically resected from January 1990 through December 1994. The avidin-biotin-peroxidase method was used to determine the expression of P53 or Rb of tumor cells using anti-P53 or anti-Rb monoclonal antibodies. The relationships between P53 or Rb protein expression and the clinicopathological parameters were analyzed.

RESULTS

Expression of P53 or Rb protein was detected in 115 (55.6%) and 136 (65.7%) of the 207 lung tumors, respectively. P53 had significantly higher positive results in patients with regional lymph node metastasis and advanced tumor stage. Rb expression was significantly lower in lung cancers with a macro- or microscopic picture of tumor necrosis. Additionally, an inverse correlation between the expression of Rb and P53 was found. By multiple variate analysis, P53 expression and pathological stage were independent, significant prognostic factors. Further analysis demonstrated P53 expression was an independent prognostic factor in stage 1, but not in other stages.

CONCLUSIONS

P53 expression is especially useful as a prognostic factor in stage 1 lung cancer.

Tissue transglutaminase: an enzyme with a split personality

Tissue transglutaminase (tTG) belongs to the family of transglutaminase enzymes that catalyze the posttranslational modification of proteins via Ca(2+)-dependent cross-linking reactions. The catalytic action of tTG results in the formation of an isopeptide bond that is of great physiological significance since it is highly resistant to proteolysis and denaturants. Although tTG-mediated cross-linking reactions have been implicated to play a role in diverse biological processes, the precise physiological function of the enzyme remains unclear. Recent data, however, suggest that the protein polymers resulting from tTG-catalyzed reactions may play a role in commitment of cells to undergo apoptosis. On the same token, tTG-mediated formation of insoluble protein aggregates may underlie the markers of numerous pathological conditions, such as the senile plaques in Alzheimer's disease and the Lewy bodies in Parkinson's disease. In addition to catalyzing Ca(2+)-dependent cross-linking reactions, tTG can also bind and hydrolyze guanosine triphosphate and adenosine triphosphate. By virtue of this ability, tTG has been identified as a novel G-protein that interacts and activates phospholipase C following stimulation of the alpha-adrenergic receptor. The ability of tTG to mediate signal transduction may contribute to its involvement in the regulation of cell cycle progression. The following review summarizes the important features of this multifunctional enzyme that have emerged as a result of recent work from different laboratories.

Free electron laser infrared wavelength specificity for cutaneous contraction

BACKGROUND AND OBJECTIVE

Short pulsed and scanned CO(2) lasers that target water molecules are currently used for cutaneous resurfacing. These CO(2) resurfacing lasers produce acute cutaneous contraction, which can be quantitated as a measure of the laser's effect. We postulated that targeting the vibrational and rotational modes of proteins with specific infrared laser wavelengths might be more effective at inducing cutaneous contraction than the CO(2) resurfacing lasers.

STUDY DESIGN/MATERIALS AND METHODS

The Vanderbilt University Free Electron Laser (FEL) was used at wavelengths between 6.0-8.6 microm. The cutaneous contraction and histologic thermal damage observed was compared to that seen with a scanned CO(2) resurfacing laser.

RESULTS

Peaks of cutaneous contraction at 7.2-7.4 and 7.6-7.7 microm were found, which were three-fold more efficient at producing cutaneous contraction than the 10.6 microm CO(2) laser. The 7.2 microm wavelength is associated with the CH bend of C-CH(3), 7.4 microm to the CH bend of O=C-CH(3), 7.6 microm to the C-C-C stretch, and 7.7 microm to the amide III (C-N-H) absorption band for proteins. Using light microscopy, an approximately 40 microm denaturation zone of dermal collagen was found at all FEL wavelengths tested, regardless of the effectiveness of cutaneous contraction.

CONCLUSION

The mechanism of action of these infrared wavelengths on cutaneous contraction is unknown, but appears to be independent of the amount of collagen denatured as observed by light microscopy. Infrared lasers such as the FEL that target vibrational and rotational modes of proteins therefore hold promise for cutaneous application at selected wavelengths.

The role of insulin and glucagon in experimental obstructive jaundice

BACKGROUND/AIMS

The oxidative phosphorylation of liver mitochondria is regulated by the amount of portal insulin available to the hepatocytes. Thus, hepatic energy is mediated by the values of blood sugar and insulin. Insulin and glucagon are the main fuel homeostats in the liver. This study was performed to investigate the concept of energy mediated by glucose, during the process of obstructive jaundice and its recovery.

METHODOLOGY

Experimental Wistar rats were studied, with bile duct tied for 4, 7 and 14 days respectively. The serum concentration and relative tissue concentration of insulin and glucagon were measured. And the common bile duct was tied for 4, 7 and 14 days, then relieved by time sequences for 4, 7 and 14 days. Serum concentration and relative tissue concentration of insulin and glucagon were also measured.

RESULTS

When the common bile duct was tied for 4, 7, and 14 days respectively, the serum concentration and relative tissue concentration of insulin declined (p < 0.05) and glucagon concentration was elevated (p < 0.05). When the common bile duct was tied for 4, 7 and 14 days, then relieved by time sequences for 4, 7 and 14 days, the concentrations of insulin in both groups appeared to decline at first (p < 0.05) and then progressively increase (p < 0.05). The concentrations of glucagon exhibit the reverse behavior. Both serum and tissue concentration are elevated at first (p < 0.05), then progressively decline (p < 0.05).

CONCLUSIONS

These studies indicated that, during obstructive jaundice, more fuel is demanded to make up for the energy deficiency. In spite of surgical or non-surgical relief of obstructive jaundice, the energy reserve is still not sufficiently recovered. The recovery of the hepatic energy reserve takes longer than we expected.

[Physiological analysis of a mathematical model for predicting somatic eigenstates under combined stresses]

Objective. To put a mathematical model for predicting human somatic eigenstates (HS) into practical engineering design of countermeasures against combined stresses (hypoxia, heat, noise and vibration) in an aircraft cabin, and confirm the model from the human physiological viewpoint. Method. Published works on these 4 stresses were employed to verify the main and interactive effects which had been previously proved mathematically. Result. The main effects of 4 stresses and the significant interactive effects of 2 from 4 stresses agreed with the published experiments in single or in the same combination of these stresses. Conclusion. The model is reasonable in human physiological consideration and has been adopted in engineering design.

Mosquito cathepsin B-like protease involved in embryonic degradation of vitellin is produced as a latent extraovarian precursor

Here we report identification of a novel member of the thiol protease superfamily in the yellow fever mosquito, Aedes aegypti. It is synthesized and secreted as a latent proenzyme in a sex-, stage-, and tissue-specific manner by the fat body, an insect metabolic tissue, of female mosquitoes during vitellogenesis in response to blood feeding. The secreted, hemolymph form of the enzyme is a large molecule, likely a hexamer, consisting of 44-kDa subunits. The deduced amino acid sequence of this 44-kDa precursor shares high similarity with cathepsin B but not with other mammalian cathepsins. We have named this mosquito enzyme vitellogenic cathepsin B (VCB). VCB decreases to 42 kDa after internalization by oocytes. In mature yolk bodies, VCB is located in the matrix surrounding the crystalline yolk protein, vitellin. At the onset of embryogenesis, VCB is further processed to 33 kDa. The embryo extract containing the 33-kDa VCB is active toward benzoyloxycarbonyl-Arg-Arg-para-nitroanilide, a cathepsin B-specific substrate, and degrades vitellogenin, the vitellin precursor. Both of these enzymatic activities are prevented by trans-epoxysuccinyl-L-leucylamido-(4-guanidino)butane (E-64), a thiol protease inhibitor. Furthermore, addition of the anti-VCB antibody to the embryonic extract prevented cleavage of vitellogenin, strongly indicating that the activated VCB is involved in embryonic degradation of vitellin.

Differential expression of the lysosome-associated membrane proteins in normal human tissues

The lysosome-associated membrane proteins LAMP-1 and LAMP-2 have closely related structures, with 37% sequence homology, and are major constituents of the lysosomal membrane. Their roles are unknown, but they are thought to be structural or functional components of the lysosomal membrane. Recent reports suggest that despite their similar structure and common localization, LAMP-1 and LAMP-2 may have different functions. In our further study of these two molecules, the presence of LAMP-1 and LAMP-2 in a variety of human tissues was analyzed by immunohistochemistry, and their localization was compared to that of cathepsin D, a lysosomal hydrolase. the tissue content of LAMP-1 and LAMP-2 and their respective mRNAs were also analyzed by Northern and Western blotting. The LAMP molecules were detected by immunohistochemistry primarily in metabolically active cells, with a cytoplasmic distribution similar to that of cathepsin D and consistent with their predominant localization in lysosomes. However, there were marked differences in the intensity of staining and, in some cases, the localization of the three proteins. For example, there was much stronger staining for LAMP-2 than LAMP-1 in brain tissue and prostate ductal cells. These differences in localization were consistent with the results obtained in Western blotting of protein extracted from the tissues. The pattern of mRNA expression was similar in all of the examined tissues, with a single mRNA identified for LAMP-1 and two splice variant forms seen for LAMP-2. Our studies of these molecules in human tissues support the conclusion that the expression of the molecules is independently controlled in some tissues, suggesting that the molecules may have independent as well as similar functions.

A simplified regimen of weekly high dose 5-fluorouracil and leucovorin as a 24-hour infusion in patients with advanced colorectal carcinoma

BACKGROUND

Reports of in vitro experiments in colorectal carcinoma cells suggest that prolonged cellular exposure to 5-fluorouracil (5-FU) combined with relatively low concentrations of leucovorin (LV) provides optimal enhancement of 5-FU efficacy. In this study, a simplified regimen of weekly 24-hour infusion of high dose 5-FU combined with a relatively low dose of LV was used to treat patients with advanced colorectal carcinoma.

METHODS

Thirty-six patients with advanced colorectal carcinoma received 5-FU, 2600 mg/m2, admixed with LV, 100 mg/m2, in a portable infusion pump administered intravenously over a 24-hour period. High dose 5-FU/LV was delivered once a week for 5 consecutive weeks followed by a 1-week recovery period. All patients were assessable for toxicity and response.

RESULTS

Two complete responses and 15 partial responses were observed (response rate of 47.2%; 95% confidence interval, 30.1-64.4%). The median response duration was 9.6 months. The median survival and time to progression were 11.9 months and 7.1 months, respectively. The toxicity was mild and acceptable. The major dose-limiting factors were hand-foot syndrome and fatigue.

CONCLUSIONS

This simplified regimen of weekly 24-hour continuous infusion of high dose 5-FU/LV is an effective regimen in the treatment of patients with advanced colorectal carcinoma. Further study of the pharmacokinetics of combination therapy with 5-FU and LV as used in this regimen and its correlation with response and toxicity is warranted.

Weekly 24-h infusion of high-dose 5-flurouracil and leucovorin in patients with advanced gastric cancer

The effect of biochemical modulation of weekly high-dose 5-fluorouracil (5-FU) 24 h infusion by leucovorin (LV) in the treatment of 39 consecutive patients with advanced gastric cancer without prior chemotherapy from October 1996 to August 1997 was examined. There were 21 male and 18 female patients with a median age of 56 years. The regimen consisted of 5-FU 2600 mg/m2 and LV 150 mg administered by 24 h infusion weekly for 6 weeks followed by a 2 week break. The treatment was repeated every 8 weeks until disease progression, patient refusal or unacceptable toxicity. Placement of a central vascular device and a portable external infusion pump was required in all patients and was used for outpatient treatment. The response to treatment was evaluated every 8 weeks. A total of 395 chemotherapy treatments were given with a mean of 10 (2-24). This response rate was: 33% (12 of 36) partial response (PR) rate, 33% (12 of 36) stable disease (SD) and 33% (12 of 36) progressive disease (PD). In general, the toxicity was mild but two toxic deaths occurred, one due to neutropenic sepsis and the other due to hyperammonemia. The median time to progression was 4 months. The overall median survival was 7 months. The survivals of the PR, SD and PD were 12, 8 and 5 months, respectively. This regimen showed a modest activity against gastric cancer with acceptable toxicity. Weekly 24 h infusion of high-dose 5-FU with LV in an outpatient setting for patients with gastric cancer is feasible and deserves further study as a basis for combination therapy.

Role of angiogenesis in hepatitis and hepatocellular carcinoma

BACKGROUND/AIMS

Hepatocellular carcinoma (HCC) is usually a hypervascular tumor. Factor VIII-related antigens, including von Willebrand factor, are known to be expressed in HCC, which cause capillarization of the sinusoids of HCC. Capillarization of hepatic sinusoids may play a role in hepatocarcinogenesis and its metastasis. The aim of this study is to clarify the expression of Factor VIII in patients with hepatitis B or C (n = 18) and HCC (n = 16).

METHODOLOGY

All specimens were sufficient for immunohistochemical study of the neo-angiogenesis with regard to clinical results. Microvessel count per square millimeter (MVC) and hot spot of microvessel per square millimeter (HSV) were measured from the histochemical study.

RESULTS

In the patients with hepatitis group, the positive staining on the vessels of the portal triad was 11.1% (2/18) but in the non-neoplastic tissue of HCC patients the positive rate was 68.7% (11/16) showing a significant difference from the hepatitis group. The amount of vasculatures was easily found in the surrounding capsule of resected HCC. The MVC of the capsule was 10.17 +/- 2.78 and 13.66 +/- 5.42 for the HCC with non-direct invasion and direct invasion during operation, respectively. The HSV of capsules were 7.51 +/- 2.09 and 9.14 +/- 4.02 for the non-invasion and invasion, respectively. Therefore, in our study, it is clear that the high MVC or HSV scores were found in patients of direct invasion. However, there was no relation between hepatitis B or hepatitis C to the tumor invasiveness. The median survival times were 21.5 months for the non-invasive group and 14.5 months for the invasive group (p < 0.05). The positive rate of Factor VIII in the vessels of the portal triad were 60% and 83.3% for the non-invasive and invasive groups, respectively. However, the lower values of MVC and HSV showed a trend toward a longer recurrence time.

CONCLUSIONS

It is pertinent to prove that the high score of neo-angiogenesis has a high risk of recurrence. In addition, it is wise to pay more attention to the interval of the follow-up study to detect the recurrent lesion earlier, where possible, in the patient with a high score of microvascularity.

Risk of transient hyperammonemic encephalopathy in cancer patients who received continuous infusion of 5-fluorouracil with the complication of dehydration and infection

From 1986 to 1998, 29 cancer patients who had 32 episodes of transient hyperammonemic encephalopathy related to continuous infusion of 5-fluorouracil (5-FU) were identified. None of the patients had decompensated liver disease. Onset of hyperammonemic encephalopathy varied from 0.5 to 5 days (mean: 2.6 +/- 1.3 days) after the initiation of chemotherapy. Plasma ammonium level ranged from 248 to 2387 microg% (mean: 626 +/- 431 microg%). Among the 32 episodes, 26 (81%) had various degrees of azotemia, 18 (56%) occurred during bacterial infections and 14 (44%) without infection occurred during periods of dehydration. Higher plasma ammonium levels and more rapid onset of hyperammonemia were seen in 18 patients with bacterial infections (p=0.003 and 0.0006, respectively) and in nine patients receiving high daily doses (2600 or 1800 mg/m2) of 5-FU (p=0.0001 and < 0.0001, respectively). In 25 out of 32 episodes (78%), plasma ammonium levels and mental status returned to normal within 2 days after adequate management. In conclusion, hyperammonemic encephalopathy can occur in patients receiving continuous infusion of 5-FU. Azotemia, body fluid insufficiency and bacterial infections were frequently found in these patients. It is therefore important to recognize this condition in patients receiving continuous infusion of 5-FU.

Unexpected mortality from the use of E. coli L-asparaginase during remission induction therapy for childhood acute lymphoblastic leukemia: a report from the Taiwan Pediatric Oncology Group

The relative efficacy and toxicity of E. coli L-asparaginase and epidoxorubicin used in remission induction therapy for childhood acute lymphoblastic leukemia (ALL) were assessed in a randomized trial conducted in Taiwan. All patients had standard-risk ALL, defined as a leukocyte count <10 x 10(9)/l and were aged between 1 and 2 or 7 and 10 years, or a leukocyte count <50 x 10(9)/l and were aged between 2 and 7 years, without evidence of a T cell or mature B cell immunophenotype, central nervous system leukemia or expression of two or more myeloid-associated antigens. Ninety-three patients were randomized to receive E. coli L-asparaginase at 10,000 IU/m2 thrice weekly for nine doses and 108 to receive epidoxorubicin at 20 mg/m2 weekly for two doses during remission induction with daily prednisolone, weekly vincristine and, on day 22, a dose of etoposide plus cytarabine. Patients treated with L-asparaginase had a significantly higher rate of fatal infection with or without hemorrhage than did those who received epidoxorubicin during remission induction (six of 93 vs none of 108, P = 0.009), resulting in a lower rate of complete remission in the former group (93.6 vs 99.1%, P = 0.05). In addition, patients treated with L-asparaginase had a higher frequency of hyperglycemia and hypoalbuminemia. The overall rate of event-free survival was lower in patients treated with L-asparaginase than in other patients (P = 0.06); estimated 3-year rates were 72% (95% confidence interval, 55-89%) and 87.2% (78-96%), respectively. We conclude that L-asparaginase (Leunase) given at 10,000 IU/m2 for nine doses was poorly tolerated and resulted in excessive toxicity, both through its effects as a single agent and possibly through potentiation of etoposide.

Differential Helicobacter pylori infection rates in two contrasting gastric cancer risk regions of South China. China Gastric Cancer Study Group

BACKGROUND

Carriers of Helicobacter pylori are believed to have a three- to six-fold increased risk of developing gastric cancer. We have recently conducted a simultaneous cross-sectional population study on the prevalence of H. pylori infection in a cohort of asymptomatic adult volunteers in two contrasting gastric cancer risk regions of South China, Hong Kong and Changle of Fujian. Their mean annual gastric cancer mortality has been approximately 7.5 and 75/100 000 population, respectively, since the beginning of the last decade. The aim of this study was to evaluate if H. pylori prevalence bears any relationship to gastric cancer mortality rates in these two southern regions of China.

METHODS

Sera were obtained from 397 volunteers in Hong Kong. They were tested for anti-H.pylori immunoglobulin (Ig) G antibody by using a commercial enzyme-linked immunosorbent assay (ELISA) kit. Volunteers of Changle (1456) had upper endoscopy examination and were also tested for anti-H. pylori IgG antibody by the same ELISA method.

RESULTS

The overall H. pylori infection prevalence was significantly higher in Changle (80.4%) than in Hong Kong (58.4%; P< 0.01). The high prevalence is associated with more atrophic gastritis. The overall risk of gastric cancer in people of Changle is approximately five-fold that of Hong Kong (adjusted odds ratio 4.9, 95% CI 2.5-9.8).

CONCLUSIONS

It is concluded that the prevalence of H. pylori infection rates bear a direct relationship to gastric cancer mortality rates in these two southern regions of China. Thus, H. pylori most likely plays a significant aetiopathogenetic role in gastric carcinogenesis in subjects living in Changle.

Changes in gut mucosal nitric oxide synthase (NOS) activity after thermal injury and its relation with barrier failure

This study was designed to investigate changes in mucosal NOS activity after burns and its relation to barrier failure. In Experiment 1, female specific pathogen free (SPF) Sprague-Dawley rats underwent 35% total body surface area (TBSA) burn. One to six days after burn, intestinal permeability was determined from the plasma leakage of fluorescein isothiocyanate (FITC)-dextran 4400, intestinal mucosal cNOS and iNOS activity were assayed using Griess' reagent, and the cellular localization of iNOS was examined using immunostaining. In Experiment 2, S-methylisothiourea (SMT) was given (5 mg/kg, i.p. every 12 h) for 2 days to suppress inducible NOS (iNOS) activity after thermal injury. On postburn Day 2, the effect of SMT on gut mucosal NOS activity, intestinal permeability, and barrier function were evaluated. The activity of iNOS increased 24 h after the injury and up to a maximum of twofold on postburn Day 2, and decreased thereafter. The increase in iNOS activity in gut mucosa correlated well with the increase in intestinal permeability, an index for barrier failure (r = .776, p = .0002). Results from iNOS immunostaining showed that changes in mucosal iNOS activity after the burn occurred mainly in the enterocytes rather than in the macrophages. Administration of SMT decreased mucosal iNOS activity, intestinal permeability, and bacterial translocation incidence to mesenteric lymph node concurrently. In conclusion, thermal injury induces intestinal mucosal iNOS, which is principally in the enterocytes. The increased intestinal iNOS activity was closely related to barrier failure. SMT inhibited intestinal mucosal iNOS activity and prevented barrier failure as demonstrated by a decrease in BT occurrence and intestinal permeability.

Longitudinal observation and outcome of nonfamilial childhood haemophagocytic syndrome receiving etoposide-containing regimens

The long-term outcome of 22 children treated with etoposide-containing regimens for haemophagocytic syndrome (HS) were longitudinally studied; none of them had a family history of the disease. All patients received etoposide-containing (150 mg/m2/d) regimens, combined, in 16 cases, with intravenous immunoglobulin (IVIG) and prednisolone. Complete remission (CR) was achieved in 12 patients, partial remission in seven, and early mortality occurred in three. Of the 12 CR patients, only four remain alive and disease-free, with a median follow-up of 47.4 months; one CR patient died due to infection and the remaining seven had relapsed diseases. Three patients with a partial response or with relapsed disease progressed to T-cell lymphoma, characterized, in the two cases tested, by clonal chromosomal abnormalities. Epstein-Barr virus (EBV) infection was implicated in disease pathogenesis in 15/22 patients. The overall survival was 45.5%, 40.9% and 40.9% at 1, 3 and 5 years, respectively, and disease-free survival for CR patients at these same times was 45.5%, 36.4% and 36.4%. The etoposide-containing regimen would appear to be an effective initial therapeutic option for childhood HS. However, in view of the frequency of partial remissions and relapsed disease, a more intensive chemotherapy or bone marrow transplantation should be applied. The progression to EBV-containing T-cell lymphoma in three patients is consistent with the previous observation that EBV-associated HS is a potentially malignant disease.

Specific inhibition of iNOS decreases the intestinal mucosal peroxynitrite level and improves the barrier function after thermal injury

Failure of GI tract mucosa to act as a barrier against bacterial translocation (BT) has been proposed as a potential source of sepsis and subsequent multiple organ failure post thermal injury. Nitric oxide (NO) is an inorganic radical produced by NO synthase (NOS) from L-arginine. Gut mucosal constitutive NOS (cNOS) provides protection for itself. In contrast to cNOS, inducible NOS (iNOS) releases far greater amounts of NO, promotes oxidative reactions and is responsible for tissue injury. Peroxynitrite formed by the rapid reaction between superoxide and NO, is a toxic substance that contributes to tissue injury in a number of biological systems. This study was designed to investigate the effect of iNOS specific inhibitor S-methylisothiourea (SMT) on the postburn intestinal mucosal barrier function and the possible mechanism of SMT's action. Female SPF Sprague Dawley rats underwent 35% total body surface area (TBSA) or sham burn. Either SMT or the same volume of saline was given (5 mg/kg, i.p. q 12 h) for 2 days to assess the effect of iNOS inhibition. On postburn day 2, the intestinal mucosal cNOS and iNOS activity were assayed by using Griess' reagent, the mesenteric lymph node (MLN), spleen and liver were collected and cultured for BT assay and the cellular localization of nitrotyrosine, a marker for peroxynitrite activity, was examined by immunostaining. After thermal injury in rats, administration of SMT for 2 days decreased the intestinal mucosal iNOS activity/ tNOS activity ratio and the BT incidence. Nitrotyrosine immunostaining of the intestinal mucosa showed a decrease in the SMT-treated group. These findings suggest that SMT, a specific inhibitor for iNOS improves the barrier function after burn by suppression of the intestinal mucosal iNOS activity. The decrease in NO production resulted in decreased formation of peroxynitrite and subsequently decreased damage of mucosal tissue.

Primary pericardial mesothelioma with cardiac tamponade and distant metastasis: case report

Although cardiac tamponade is a well-known complication of malignancy, it is uncommon as the initial manifestation. The antemortem diagnosis is difficult and distant metastasis is extremely rare. The presentations of primary pericardial mesothelioma are nonspecific. Pathologically, mesothelioma is the most common in primary tumors of the pericardium. Radical surgery can be used to treat a localized mesothelioma. However, the therapy for advanced primary pericardial mesothelioma is usually palliative because it is resistant to irradiation, and chemotherapy does not markedly improve the outcome. The prognosis is uniformly poor. The median survival from the onset of symptoms is 6 months. We present a 67-year-old woman with cardiac tamponade 4 months prior to a definitive diagnosis of primary pericardial mesothelioma. A computed tomogram confirmed multiple well-enhanced nodules in the pericardium, lungs and liver. Unfortunately, the patient died of multiple organ failure.

Emerging tobacco hazards in China: 1. Retrospective proportional mortality study of one million deaths

OBJECTIVE

To assess the hazards at an early phase of the growing epidemic of deaths from tobacco in China.

DESIGN

Smoking habits before 1980 (obtained from family or other informants) of 0.7 million adults who had died of neoplastic, respiratory, or vascular causes were compared with those of a reference group of 0.2 million who had died of other causes.

SETTING

24 urban and 74 rural areas of China.

SUBJECTS

One million people who had died during 1986-8 and whose families could be interviewed.

MAIN OUTCOME MEASURES

Tobacco attributable mortality in middle or old age from neoplastic, respiratory, or vascular disease.

RESULTS

Among male smokers aged 35-69 there was a 51% (SE 2) excess of neoplastic deaths, a 31% (2) excess of respiratory deaths, and a 15% (2) excess of vascular deaths. All three excesses were significant (P<0.0001). Among male smokers aged >/70 there was a 39% (3) excess of neoplastic deaths, a 54% (2) excess of respiratory deaths, and a 6% (2) excess of vascular deaths. Fewer women smoked, but those who did had tobacco attributable risks of lung cancer and respiratory disease about the same as men. For both sexes, the lung cancer rates at ages 35-69 were about three times as great in smokers as in non-smokers, but because the rates among non-smokers in different parts of China varied widely the absolute excesses of lung cancer in smokers also varied. Of all deaths attributed to tobacco, 45% were due to chronic obstructive pulmonary disease and 15% to lung cancer; oesophageal cancer, stomach cancer, liver cancer, tuberculosis, stroke, and ischaemic heart disease each caused 5-8%. Tobacco caused about 0.6 million Chinese deaths in 1990 (0.5 million men). This will rise to 0.8 million in 2000 (0.4 million at ages 35-69) or to more if the tobacco attributed fractions increase.

CONCLUSIONS

At current age specific death rates in smokers and non-smokers one in four smokers would be killed by tobacco, but as the epidemic grows this proportion will roughly double. If current smoking uptake rates persist in China (where about two thirds of men but few women become smokers) tobacco will kill about 100 million of the 0.3 billion males now aged 0-29, with half these deaths in middle age and half in old age.

Substituted 3beta-phenylethynyl derivatives of 3alpha-hydroxy-5alpha-pregnan-20-one: remarkably potent neuroactive steroid modulators of gamma-aminobutyric acidA receptors

Neuroactive steroids are positive allosteric modulators of gamma-aminobutyric acidA (GABAA) receptor complexes. Synthetic modification generally does not increase neuroactive steroid potency beyond that of the naturally occurring progesterone metabolite, 3alpha-hydroxy-5alpha-pregnan-20-one (3alpha,5alpha-P). Recently, it has been shown that introduction of appropriately para-substituted phenylethynyl groups at the 3beta-position of 5beta steroids increases receptor potency. The present report presents the synthesis and pharmacological profile of an analogous series of 5alpha steroids. The most striking feature of this series is the further enhancement of in vitro and in vivo potency obtained. In particular, 3beta-(p-acetylphenylethynyl)-3alpha-hydroxy-5alpha-pr egnan-20-one (Co 152791) was 11-, 16- and 49-fold more potent than 3alpha, 5alpha-P in modulating the binding of [35S]TBPS, [3H]flunitrazepam and [3H]muscimol, respectively, in rat brain membranes (Co 152791 IC50 or EC50 = 2-7.5 nM). Similarly, Co 152791 was 3- to 20-fold more potent than 3alpha,5alpha-P as an inhibitor of [35S]TBPS binding in human recombinant receptor combinations containing alpha1, alpha2, alpha3 or alpha5 and beta2gamma2L subunits (Co 152791 IC50 1.4-5.7 nM). Co 152791 displayed low efficacy and 3alpha,5alpha-P had low potency at alpha4/6beta3gamma2L GABAA receptor complexes. Interestingly, Co 152791 demonstrated remarkable potency as a potentiator of GABA-evoked currents in Xenopus oocytes expressing alpha1beta2gamma2L receptors (EC50 0.87 nM), being 184-fold more potent than 3alpha,5alpha-P. High in vitro potency was also reflected in enhanced in vivo activity in that Co 152791 exhibited exceptional anticonvulsant potency, protecting mice from pentylenetetrazol-induced seizures at a approximately 5-fold lower dose than 3alpha,5alpha-P after i.p. administration (Co 152791 ED50 0.6 mg/kg). Moreover, Co 152791 was orally active (ED50 1.1 mg/kg) and exhibited a therapeutic index of 7 relative to rotorod impairment. The remarkable potency of Co 152791 as a positive allosteric modulator of GABAA receptors may be explained by its interaction with an auxiliary binding pocket in the neuroactive steroid binding site. In addition, modification at the 3beta-position probably hinders metabolism of the 3alpha-hydroxy group contributing to the exceptional anticonvulsant potency of this compound relative to other neuroactive steroids.

Segmental colectomy in the management of colonic inertia

Subtotal colectomy with ileorectostomy has been proposed for the management of colon inertia-type constipation. However, many patients experience frequent bowel movements, watery diarrhea, or both after such a treatment. The purpose of this study is to determine the proper colectomy with which to treat colon dysmotility constipation without the negative side effects of frequent bowel movements, watery diarrhea, or both. Forty idiopathic constipation patients were studied. All of the patients showed a prolonged right or left colon transit time and normal transit time of the sigmoid and rectum. They received different types of colectomies (left, right, and subtotal) according to the distribution or accumulation of markers in the colon. Within 3 months of surgery, all of the patients experienced a dramatic improvement of their symptoms without frequent bowel movements or watery diarrhea. No significant complications developed after surgery. All the patients were followed up for at least 2 years. Most of them (37 cases) still had satisfactory bowel movements and no other constipation symptoms. However, 3 of the 40 cases developed symptoms of constipation 1 1/2 to 2 years after surgery. They all received subtotal colectomy with ileorectal anastomosis subsequently. They reobtained satisfactory bowel movements and experienced a subsidence of other constipation symptoms 3 months later. These results suggest that directed segmental colectomy can improve colonic inertia constipation without the consequence of frequent bowel movements and diarrhea.

Pancreatic pseudocyst involving the spleen

The pseudocyst of the pancreas is a frequent complication of acute pancreatitis. The splenic involvement from the pancreatic pseudocyst is an uncommon entity. A 40-year-old man, who had a five-year history of alcohol consumption, was referred to our hospital for treatment of throbbing pain over left upper quadrant (LUQ) of the abdomen. Except for LUQ tenderness, physical examination was essentially normal. MRI showed two cystic lesions in splenic hilum and pancreatic tail, and prominent vessels in left infrasplenic area and gastrosplenic ligament. Angiography revealed splenic vein thrombosis. Because of persistent LUQ pain, he underwent laparotomy. During the operation, we found the cysts in pancreatic tail and splenic hilum. The cystic content was aspirated to check amylase, which showed the level of amylase being as high as 20,000 IU/L. The diagnosis of a pancreatic pseudocyst involving the spleen was established. Splenectomy and distal pancreatectomy were performed to remove both cysts. The pathologic examination of the resected spleen showed splenic infarction with cyst formation and pancreatic pseudocyst. The patient recovered uneventfully after operation.

Tumor fever in patients with nasopharyngeal carcinoma: clinical experience of 67 patients

From 1982 through 1996, 67 patients with nasopharyngeal carcinoma (NPC) proven to have tumor fever (TF) were analyzed. All were in metastatic stage when TF occurred. Forty-five patients (67%) had recurrent disease. Thirty-eight (57%) had fever before metastatic lesions were detected. The metastatic sites were: 84% in bone, 69% in liver, and 19% in lung. Multiple-organ metastases were found in 64% of the patients. Nine patients (13%) had bone-marrow invasion. When TF was present, 22 (33%) patients had other paraneoplastic syndromes, of which leukemoid reaction (LR) was seen most frequently. After the initiation of naproxen or indomethacin, most patients had complete lysis of the fever within 48 hours. Of the six patients receiving chemotherapy as the initial therapy, all of their temperatures returned to normal range after the treatment. Some patients, particularly those with tumor progression, developed TF again when antipyretic drugs were discontinued. The median survival time was 5 months. In conclusion, TF in NPC is usually a manifestation of metastatic disease. Tumor fever often associates with other paraneoplastic syndromes. Naproxen, indomethacin, and systemic chemotherapy all had effectiveness in ameliorating TF. Systemic metastases should be suspected in NPC patients with fever of unknown origin.

[Laboratory medicine in Taiwan]

Laboratory medicine and hospital central laboratory system were adopted in Taiwan after World War II. In medical schools, laboratory medicine or clinical pathology teaching is allocated to junior students. Three years of clinical pathology or four years of anatomical pathology training is required for pathology resident. Recent trend indicates that both the hospitals and the young doctors favor the five years combined C.P. (two-years) and A.P. (three years) training program. At present, 75 clinical pathologists and 213 anatomical pathologists are qualified. Approximately 70% of them work in medical centers and medical schools. Consequently, the medium and small size hospitals suffer from serious shortage of pathologist. Studies during the part 50 years indicate substantial difference in the improvement of laboratory medicine and central laboratory before and after 1975. Significant improvement in the working space, facility, equipment, staff, quality control and productivity was evident after 1975. The three health care policies contributing to the overall improvement are: 1. hospital accreditation project, 2. medical care network plan, and 3. medical specialist system.

Weekly 24 h infusion of high-dose 5-fluorouracil and leucovorin in patients with biliary tract carcinomas

From October 1995 to June 1997, 19 chemotherapy-naive patients with pathology-proven locally advanced or metastatic biliary tract carcinomas (BTC) were enrolled. The regimen consisted of 5-fluorouracil (5-FU) 2600 mg/m2 and leucovorin (LV) 150 mg by weekly 24 h infusion for 6 weeks and followed by a 2 week break. The treatment was terminated if disease progressed, the patient refused or unacceptable toxicity occurred. All patients required a Port-A catheter insertion and were treated at outpatient clinics by portable infusion pumps. There were 12 males and seven females with a median age of 62 years (range 45-77). The primary tumor sites were nine intrahepatic cholangiocarcinomas (CC), three perihilar CC, one distal BTC and six gallbladder cancers. A total of 179 chemotherapy sessions were given with a mean of 9.5 (range 2-18). Eighteen patients were evaluable for response. The response rates were: 33% (six of 18) partial response (PR), 39% (seven of 18) stable disease (SD) and 28% (five of 18) progressive disease (PD). All of the patients were evaluable for toxicity. The most common toxicities were mild fatigue (nine of 19, 47%), loss of appetite (nine of 19, 47%), skin hyperpigmentation (five of 19, 26%) and diarrhea (two of 19, 11%). Only one patient had grade IV myelotoxicity with sepsis but without treatment-related death. The median time to progression was 4 months. The overall median survival time was 7.0 months. The median survival time of the PR was not reached, SD was 8.0 months and PD 3.5 months. In conclusion, weekly high-dose 5-FU with LV by 24 h infusion in an outpatient setting for patients with BTC is effective, only mildly toxic and deserves further study.

A dynamic local bump system for producing synchrotron radiation with an alternating elliptical polarization

To facilitate high-sensitivity soft X-ray magnetic circular dichroism experiments, a dynamic local bump system has been developed at the SRRC storage ring. This system was devised to vary dynamically the vertical slope of the electron beam in a bending magnet, producing, in the electron orbit plane, soft X-rays with an alternating elliptical polarization. The local bump was created by using two pairs of vertical correctors located on each side of the bending magnet. The bump strength coefficient was obtained both from calculated estimation and from measured beam-response matrices. Control electronics for proper bump strength settings were designed to incorporate the existing orbit-corrector function. A corresponding graphic user interface was implemented so that the bump amplitude could be easily adjusted. The performance of this system is presented. Disturbance on the stored electron beam orbit was observed while flipping the corrector polarity during EPBM (elliptical polarization from bending magnets) operation. A local feedback loop, developed to eliminate such disturbance on other beamlines, is also described.

Calcium phosphate coating on titanium substrate by a modified electrocrystallization process

Modification of ethyl alcohol added aqueous electrolyte for depositing calcium phosphate on titanium substrates by a electrocrystallization method is described. Film coated in the electrolyte with ethyl alcohol addition is more homogeneous and the growth rate is higher. The optimum quantity of ethyl alcohol added is 50% of the electrolyte. Although the pH value of electrolyte varies as ethyl alcohol is added, the phases of the deposited film remain the same, and are hydroxyapatite and brushite. The development of the microstructure of the coated film during deposition is discussed.

Laparoscopic resection of a primary retroperitoneal mucinous cystadenoma: report of a case

Primary retroperitoneal mucinous cystic tumors are extremely rare, and although their histogenesis is still uncertain, several theories have been proposed. Traditionally, transabdominal laparotomy and enucleation of the cyst is the treatment of choice and laparoscopic resection has not previously been reported. This paper presents the case of a 48-year-old woman in whom a primary retroperitoneal cystic mass, 15 x 13 x 9 cm in size, was successfully resected through the laparoscope. Pathological examination revealed a mucinous cystadenoma with borderline malignancy. The patient had a prompt recovery and there was no evidence of recurrence at her 8-month follow-up. However, the prevention of cystic fluid spillage during laparoscopic manipulation is important, especially when the pathology of the retroperitoneal cyst is unclear.

Malignant thyroid teratoma of an adult: a long-term survival after chemotherapy

Adult primary malignant teratoma of the thyroid is a rare disease that has a poor outcome despite aggressive therapy. A 32-year-old woman underwent a simple lobectomy of the thyroid for a progressively enlarged nodule in August 1990. Pathologic assessment of the tumor revealed a malignant teratoma. The physical examinations and image studies failed to find tumor in other sites. She subsequently received 6 courses of chemotherapy with cisplatin, etoposide, and bleomycin. She experienced a complete response to chemotherapy and remained disease-free for 6.5 years. This tumor must be included in the differential diagnosis of a thyroid tumor and may be treated as a testicular germ-cell tumor for which chemotherapy may be recommended.

Blunted serum erythropoietin response to anemia in patients polytransfused for beta-thalassemia major

PURPOSE

To investigate the response of erythropoietin (EPO) to anemia in patients polytransfused for beta-thalassemia major.

PATIENTS AND METHODS

We measured the serum EPO levels and the concurrent hemoglobin (Hb) concentrations in 40 patients polytransfused for beta-thalassemia major, in 18 patients with iron deficiency anemia (IDA), and 32 healthy subjects. Serum EPO levels were assayed by an enzyme immunoassay.

RESULTS

In both groups with beta-thalassemia major and IDA, serum EPO levels were significantly elevated (114 +/- 71 and 239 +/- 217 mU/mL, respectively). There was a significant inverse correlation between log EPO values and Hb concentrations in patients with beta-thalassemia major (r = 0.61; p < 0.01) and IDA (r = 0.81; p < 0.01). In a semilogarithmic plot, the slope of the regression line obtained in patients with beta-thalassemia major was significantly lower than that of IDA (p < 0.01), suggesting a blunted EPO response to anemia in patients polytransfused for beta-thalassemia major. The elevation of serum EPO in patients with beta-thalassemia major was poorly related to clinical variables except serum ferritin.

CONCLUSIONS

We conclude that a significant inverse relationship between serum EPO levels and Hb concentration exists in patients with beta-thalassemia major. However, this EPO response in patients with anemia caused by beta-thalassemia major may be blunted when compared to patients with IDA.

Ultrasound-guided percutaneous transhepatic drainage of gallbladder followed by cholecystectomy for acute cholecystitis--10 years' experience

Acute cholecystitis is a common disease which may carry the risk of complications, including empyema, perforation, abscess, peritonitis and sepsis. Percutaneous transhepatic drainage of the gallbladder (PTGBD) with antibiotics can provide prompt decompression of gallbladder in acute cholecystitis and interrupt the natural history of the disease effectively. From July 1986 to June 1996, 154 patients with acute cholecystitis were reviewed retrospectively in Kaohsiung Medical College Hospital. The chief symptoms and signs were pain (98.1%), fever (57.1%) and jaundice (37.7%). WBC count more than 10,000 was noted in 116 (75.3%) patients. Associated diseases included empyema: 42 (27.3%), septic shock: 14 (9.1%), diabetes mellitus: 13 (8.4%), pancreatitis: 10 (6.5%), perforation: 7 (4.5%), liver cirrhosis: 6 (3.9%) and respiratory failure: 1 (0.6%). All of them underwent ultrasound-guided PTGBD immediately after the diagnosis was established. The symptoms and signs disappeared soon after this procedure. Bacterial culture was found positive in 104 (67.5%) of 154 patients in which Escherichia coli (51.9%) was the most common organism, followed by Klebsiella pneumonia (20.2%). After acute stage, 138 patients obtained the cholangiography via PTGBD tube. Gallbladder stones were only noted in 56 (40.6%) patients, gallbladder stone concomitant with common bile duct stone in 26 (18.8%), cystic duct obstruction in 25 (18.1%), acalculous cholecystitis in 21 (15.2%), gallbladder perforation in 1 (0.7%), choledochocyst in 1 (0.7%), and cholecystocolonic fistula in 1 (0.7%). There were 135 patients to undergo surgery after the clinical condition was stable. The operative findings included gallbladder stones only in 88 (65.2%), gallbladder stone concomitant with common bile duct stone in 34 (25.2%), acalculous cholecystitis in 13 (9.6%), choledochocyst in 1 (0.7%), and cholecysto-colonic fistula in 1 (0.7%). The postoperative complications included wound infection 8 (5.9%), UGI bleeding 3 (2.2%), acute renal failure 1 (0.7%) and acute respiratory failure 1 (0.7%). The postoperative mortality rate was 0.7% (1/135), which was much lower than those of previous reports, which not undergoing PTGBD initially. It led us to conclude that PTGBD, as an initial preoperative modality to treat acute cholecystitis, is effective in decreasing postoperative morbidity and mortality.

Gastric cancer with obstructive uropathy: clinical experience with 17 cases

BACKGROUND

Gastric cancer can spread to either the paraaortic area or pelvis causing ureteral obstruction.

METHOD

Between 1984 and 1996, 17 patients with gastric cancer were proven to have obstructive uropathy (OU). Of these, 12 (70%) had poorly differentiated adenocarcinomas.

RESULTS

The obstructed levels were at the proximal ureter (7 cases), distal ureter (7 cases), and at multiple sites in the ureter (3 cases). The mucosa of the ureter tended to be spared. In 3 cases, OU was the initial presentation. Peritoneal carcinomatosis was noted in all cases. Most cases demonstrated obvious paraaortic lymph node and/or pelvic metastases. Management of ureteral obstruction included percutaneous nephrostomy (PCN) in 8 cases, and cystoscopic placement of a ureteral stent in 9 cases with double-J stents used in 8. Insertion of the double-J stent failed in 1 case initially. Four cases using double-J stents resulted in occlusion within 1 month, of which 3 subsequently were successfully changed to PCN.

CONCLUSION

Gastric cancer with OU can obstruct the ureter at any level. Double-J stents exhibited a high failure rate in these patients necessitating a switch to PCN. We could also choose PCN as the initial procedure to preserve renal function.

Primary diffusely infiltrative adenocarcinoma of the colon and rectum

BACKGROUND

Primary diffusely infiltrative colorectal adenocarcinoma is rare. About 100 cases have been reported in the literature. The mucosal alterations in this type of tumor and their clinicopathological characteristics in relation to survival are not clear.

METHODS

We retrospectively reviewed 30 cases of primary diffusely infiltrative colorectal adenocarcinoma operated upon in a single institution.

RESULTS

Eighteen (60%) of these 30 patients were women. The average age at diagnosis was 47.4 (SD, 19.3) years. Eighteen tumors (60%) were located in the rectum. The tumors could be classified into two major types. A type 1 tumor had minimal mucosal alteration and no discrete ulcer. A type 2 tumor was associated with a discrete ulcer. The type 1 tumor was more frequently associated with intracellular or extracellular mucin production and stage IV disease. Hematogenous spread (including peritoneal carcinomatosis) was more frequently seen in type 1 than in the type 2 tumors (61% vs. 18%, p = 0.013). The overall median cancer-specific survival time was 15 (SE, 3; 95% confidence interval, 10-21) months. TNM stage is the only significant factor in predicting outcome (p = 0.016). When compared with stages II and III, the odds of death for stage IV was 2.9 (95% confidence interval: 1.1-7.4).

CONCLUSION

Diffusely infiltrative colorectal cancer can be separated into two subtypes according to the presence of a discrete ulcer. The type 1 tumor (without a discrete ulcer) was associated with a higher frequency of hematogenous spread. TNM Stage was the only important clinicopathological factor in determining outcome.

Subsensitivity of adenylyl cyclase-coupled receptors on mononuclear leukocytes from drug-free inpatients with a major depressive episode

Previous studies have demonstrated blunted beta-adrenergic responsivity in leukocytes from depressed patients. We sought to determine if this blunted cyclic adenosine monophosphate (AMP) response is specific for beta-adrenergic receptors (homologous), or whether other adenylyl cyclase-coupled receptors are also involved (heterologous), in order to localize this effect at the level of the receptor versus the coupling protein or the transducer, adenylyl cyclase. We studied adenylyl cyclase-mediated responses in peripheral blood mononuclear cells from 95 drug-free patients with a major depressive episode and 69 healthy controls. We found a similar degree of decrease in the peak cyclic AMP response to activation of the beta-adrenergic receptor (28%) and the prostaglandin receptor (34%) in the depressed patients, which indicated heterologous desensitization. Forskolin cyclic AMP responses were not blunted. Blunting of cyclic AMP responses to isoproterenol did not appear to correlate with levels of plasma norepinephrine and epinephrine or hypothalamic-pituitary-adrenocortical function. The absence of a decrease in the peak forskolin-generated cyclic AMP response, which involves direct activation of adenylyl cyclase, suggests an abnormality at the level of the coupling protein in these adenylyl-coupled receptors in depressed patients. Future studies need to determine whether this leukocyte signal transduction defect in depression also involves brain adenylyl cyclase-coupled receptors.

Pulsed high-dose dexamethasone therapy in children with chronic idiopathic thrombocytopenic purpura

PURPOSE

The effectiveness of pulsed high-dose oral dexamethasone therapy in children with refractory chronic idiopathic thrombocytopenic purpura (ITP) is evaluated.

PATIENTS AND METHODS

Seven children (5 to 16 years old) who were refractory to 2 to 5 conventional standard therapies were included in the study. Dexamethasone was administered orally at a dosage of 40 mg/m2 per day (maximum 40 mg/day) for 4 consecutive days as a cycle. The cycle was repeated once a month for 6 months.

RESULTS

One month after the first cycle, partial responses of platelet counts (> or = 50 x 10(9)/L and < 150 x 10(9)/L) were observed in three patients (43%). At the end of the sixth cycle, two patients (29%) had complete responses (> 150 x 10(9)/L) and one had a partial response. However, only one patient (14%) remained partially responsive 1 year after completion of therapy.

CONCLUSIONS

In contrast to what was observed in adults, this preliminary study suggests that pulsed high-dose oral dexamethasone therapy was not uniformly effective in children with chronic ITP.

Changes of insulin and somatostatin and their relationship to liver regeneration in experimental obstructive jaundice

The liver is a parenchymal organ that has a substantial capacity to regenerate after damage. Obstructive jaundice is a common surgical disease and potentially risky. A successful outcome of operations depends upon the hepatic regeneration reserve. Insulin is one of factors responsible for hepatotrophic regeneration and somatostatin has a reversal suppressive action. Experimental obstructive jaundice was introduced and relieved. In addition, serum insulin and somatostatin concentrations were measured. We used immuno-histochemical study of pancreatic tissue by immunogold to express the tissue relative insulin and somatostatin concentrations. Nucleolar organizer regions (NORs) were used to predict the nucleolar activity of liver cells. In our studies, we observed the serum concentrations of insulin and somatostatin were similar to the relative tissue concentration in pancreatic tissues. The relative tissue gold-particle score of insulin in group A (rats with common bile duct tied), was CONT: T4: T7: T14 = 100%: 90.5%: 68.3%: 46.2%; of somatostatin was 100%: 120%: 118.2%: 115.5% respectively. In group B (common bile duct tied for 4 days then relieved), the gold-particle score of insulin was T4: T4R4: T4R7: T4R14 = 90.5%: 62.8%: 72.2%: 95.4%; of somatostatin was 120.2%: 114.3%: 108.1%: 106.2% respectively. In group C (common bile duct tied for 7 days then relieved), the gold-particle score of insulin was T7: T7R4: T7R7: T7R14 = 68.3%: 53.3%: 73.5%; of somatostain was 118.2%: 109.4%: 104.6%: 102.1% respectively. The mean numbers of AgNORs in group A revealed CONT: T4: T7: T14 = 2.24 +/- 0.24: 3.02 +/- 0.96: 3.26 +/- 1.02:3.08 +/- 0.84, group B was T4: T4R4: T4R7: T4R14 = 3.02 +/- 0.96: 3.03 +/- 0.73: 3.36 +/- 1.12: 3.72 +/- 1.46, and group C showed T7: T7R4:T7R7: T7R14 = 3.26 +/- 1.02: 3.26 +/- 0.84: 3.31 +/- 1.24: 3.54 +/- 1.24. In conclusion, our studies suggested: (1) liver regeneration appeared promptly after obstructive jaundice developed, but prolonged cholestasis inhibited this process. (2) Insulin levels gradually fell during the process of obstructive jaundice. Those levels elevated when cholestasis was improved. Nevertheless, both insulin and hepatic regeneration power could not reflect the initial improvement of cholestasis simultaneously. It took a longer time for the improvement of cholestasis and the recovery of the liver function. (3) Patho-physiologically, somatostatin had a weak influence on hepatic regeneration during obstructive jaundice. (4) Our studies provided clues that early biliary drainage might improve hepatic regeneration capacity. Supplement of insulin during the obstructive jaundice might be helpful for the improvement of hepatic regeneration power.

Effect of SR-140333, a neurokinin-1 receptor antagonist, on airway reactivity to methacholine in sedated rats

AIM

To study the roles of neurokinins in the airway reactivity (AR) to methacholine chloride (MC).

METHODS

The effects of (S)-1-(2-[3, 4-dichlorophenyl)-1-(3-isopropoxyphenylacetyl) piperidin-3-yl]ethyl)-4-phenyl-1-azoniabicyclo [2.2.2]octane.chloride (SR-140333), a neurokinin-1 receptor antagonist, on AR to inhaled MC in diazepam-sedated rats, and on MC-induced contraction of isolated tracheal spiral strips were observed.

RESULTS

SR-140333 inhibited the increase in respiratory rate (RR) induced by MC aerosol (10-1000 mumol/m3), and the ID50 for inhibiting the response to MC aerosol (1 mmol/m3) was 4.9 micrograms.kg-1 (95% confidence limits 1.4-17.2 micrograms.kg-1). SR-140333 1 mumol.L-1 had no inhibitory effect on MC-induced tracheal contraction. Atropine blocked responses to MC both in vivo and in vitro.

CONCLUSION

Endogenous neurokinins are involved in the AR to MC in rats, at least partly mediated via neurokinin-1 receptors.

Trace elements burden in geriatric hemodialysis patients: a prospective multicenter collaborative study

INTRODUCTION

Hemodialysis therapy and the aging process have been reported to interfere with the trace element (TE) status in the body. This multicenter collaborative study on blood levels of TE in geriatric hemodialysis (HD) patients was carried out with an aim to clarify the impact of the aging process and HD therapy on the TE status in such patients.

METHODS

One hundred and fifty-one HD patients (65 male, 86 female), all aged over 60 (68.2+/-3.86 y), and 112 elderly controls (58 male, 54 female) with a mean age of 67.5+/-3.03 were enrolled. All patients underwent standard HD for at least 6 months. The artificial kidneys used were hollow-fiber dialyzers of cellulose membranes. Water used for HD was prepared by reverse osmosis. Blood was collected in the morning prior to dialysis and after fasting. Atomic absorption spectrophotometry was applied to measure blood levels of Pb, Cd and Hg as well as plasma levels of Cu, Zn and Al. Data are presented as mean +/- SEM. Student's t-test and linear regression were applied for statistics.

RESULTS

Our geriatric chronic HD patients showed a marked elevation of blood Al and decreased plasma Zn concentrations. The blood levels of Cu, Cd, Pb and Hg were within normal limits. The blood concentrations of Al, Cu and Pb were significantly higher in HD patients than in the normal elderly controls, whereas Cd and Hg were similar in both groups, and Zn were lower in HD patients. Plasma Zn value decreased as dialysis duration increased, however there was a reversely linear correlation between plasma Zn and age.

CONCLUSIONS

This data reported can be regarded as a starting point and may serve as an insight to further studies on TE imbalances in geriatric and chronic HD populations.

Perforated rectal lymphoma in a renal transplant recipient: report of a case

PURPOSE

We report the case of a renal transplant recipient with rectal lymphoma manifested by sudden onset of abdominal pain from a perforated rectum who was treated successfully with prompt surgical resection and reduction of immunosuppressants.

METHODS

An emergent anterior resection with Hartmann's procedure was done. Immunosuppressants were drastically reduced by discontinuation of cyclosporine.

RESULTS

Pathologic examination showed diffusely infiltrated large-cell malignant lymphoma with an immunoblastic feature. The patient has been followed-up for four years, with no tumor recurrence or graft rejection.

CONCLUSION

Rectal lymphoma, although rare, should be kept in the list of differential diagnoses for transplant recipients who exhibit lower gastrointestinal bleeding, intestinal obstruction, or abdominal pain.

Clonal karyotype abnormalities in EBV-associated hemophagocytic syndrome

BACKGROUND AND OBJECTIVE

An EBV-associated hemophagocytic syndrome (HS) in previously healthy children or young adults has been documented in Taiwan. The exact nature of this syndrome, i.e., either an infectious process or a neoplastic disease, remains to be clarified.

METHODS

Three patients diagnosed as having HS were studied retrospectively. Chromosomes from bone marrow were examined by a conventional trypsin-Giemsa banding technique and karyotyped at the beginning of diagnosis or during treatment. In situ hybridization studies for EBV using EBER1 were performed.

RESULTS

All three patients presented the classic manifestations of HS including fever, splenomegaly, jaundice, pancytopenia and coagulopathy. Bone marrow aspiration revealed atypical lymphocyte and histiocyte infiltration with hemophagocytosis. EBV genomes were found in bone marrow in all patients. In addition to normal mitotic cells, clonally karyotypically abnormal cells were demonstrated in all three patients whose diseases were rapidly progressive and eventually refractory to etoposide-based therapy. The consistent karyotypical abnormality of add(9)(p24) was noted in two of them.

INTERPRETATION AND CONCLUSIONS

Although HS is usually considered a reactive process, the emergence of clonal cytogenetic abnormalities should be considered a malignant entity and treated with more intensive chemotherapy. A large series of cytogenetic and molecular studies is needed to clarify the exact nature of this fatal disease.

Laparoscopic fenestration for giant liver cyst

Laparoscopic fenestration for treatment of the non-parasitic cyst of the liver has been rarely reported, but sporadic cases appeared elsewhere in the literature. Here we report four cases with symptomatic giant nonparasitic liver cysts which were treated by a laparoscopic fenestration procedure that allowed the successful removal of the cyst dome. Before starting to excise the wall of the cyst, laparoscopic-quided needle aspiration of the cyst fluid was done first in order to clean the visual field for laparoscopic intervention where possible. The cyst wall was usually slightly transparent and somewhat smooth in the external and internal surface of the cysts. It was necessary to lysis the omental adhesion sometime before starting to remove the dome of the cyst. The cyst wall of the exposed part could be removed first with heat-probe instrument through laparoscopy. Those patients were discharged and revealed an uneventful post-operative course in three cases but in one case we had to convert to the traditional laparostomy to perform resection of the multiple cystic lesions. Post-operative echographic study showed that the giant cyst had collapsed. Therefore, we believe laparoscopic fenestration for the liver cyst is simple and effective, if the patient is a candidate who requires operation to remove the dome of the giant cyst.

[Effect of SR-140333, a tachykinin NK-1 antagonist, on antigen-induced airway hyperresponsiveness in sensitized rats]

In the present study, the effects of SR-140333, ((S)-1-(2-[3,4-dichlorophenyl)-1-(3-isopropoxyphenylacetyl)piperidin- 3yl]ethyl)-4-phenyl-1-azoniabicyclo[2.2.2]octane.chloride), a nonpeptide antagonist for tachykinin NK-1 receptor, on the antigen-induced airway response to methacholine (MCh) aerosol and airway inflammation in sensitized SD rats were investigated. The baseline respiratory frequencies, tachypnea response to methacholine(MCh), the -log PC30 values of MCh and the leukocyte counts in bronchoalveolar lavage significantly increased after inhalation of 1% oval albumin(OA) aerosol. SR-140333 (152 nmol.kg-1, i.p.) or dexamethasone(368 nmol.kg-1, i.p.), bid x 3 d inhibited these responses. SR-140333 at a low dose of 0.01 mg.kg-1 showed an incomplete inhibition. From these results, we conclude that antigen challenge causes airway hyperresponsiveness and airway inflammation and that tachykinin NK-1 receptor antagonist inhibits these responses.

[A new non-invasive method for measurement of airway responsiveness in sedated rats]

Sprague-Dawley rats sedated with intraperitoneal injection of diazepam (7.5 mg/kg) were placed in a plethysmograph to measure the changes in spontaneous respiration. Inhalation of methacholine (MCh) or acetylcholine (ACh) aerosol did not alter the volume of breathing, but increased respiratory frequency (RF) to the same extent in a concentration-dependent manner. On the other hand, the tachypnea effect of MCh lasted 11 min, and that of ACh only 3 min. Urethane anesthesia inhibited spontaneous respiration and the response to MCh. Atropine, salbutamol and aminophylline inhibited MCh-induced tachypnea. In sensitized rats, the response to MCh was potentiated 6 h after inhalation of ovalbumin aerosol. The results indicate that sedation with diazepam and inhalation of MCh aerosol used in this report are suitable for measuring airway responsiveness in terms of degree of increase of respiratory frequency.

Substrate-dependent optical absorption characteristics of titanium dioxide thin films

We used the electron-beam evaporation method in various oxygen partial pressure environments to deposit TiO(2) thin films on various glass substrates at 300 degrees C. We found the threshold oxygen partial pressures above which the film is transparent are different for films on various substrates. Below the threshold oxygen partial pressure, the refractive index and the extinction coefficient of the films varied from substrate to substrate. The films on substrates with higher threshold oxygen partial pressure were associated with a higher extinction coefficient and a higher growth rate. These phenomena are correlated with the appearance of rutile phase in the anatase phase, which is also correlated with variations in the Al(2)O(3) and Na(2)O content in the substrates. The Al(2)O(3) content in the substrate tends to enhance the formation of rutile phase in the film and to give a higher extinction coefficient for the film, while the Na(2)O content in the substrate tends to retard the rutile formation in the film and to give a lower extinction coefficient for the film.

Influence of selective decontamination of the digestive tract on cell-mediated immune function and bacteria/endotoxin translocation in thermally injured rats

OBJECTIVE

To determine the influence of pretreatment with selective decontamination of the digestive tract (SDD) on systemic immunosuppression, and the relationship between bacteria/endotoxin translocation and abnormalities of immune function in thermally injured rats.

DESIGN, MATERIALS, AND METHODS

Animals were subjected to a 40% full-thickness scald injury, and divided into SDD-treated and control groups. The treatment group received SDD (polymyxin E, tobramycin, and 5-flucytosine) by gavage twice daily for 3 days before the experiment and continued for 5 days after thermal injury. The control group was given the same amount of water. The parameters reflecting cell-mediated immunity, including splenocyte proliferation in response to mitogens, interleukin 2 (IL-2) production, and lymphocyte subpopulation, were measured before injury and 1 and 5 days after burn, respectively.

MEASUREMENTS AND MAIN RESULTS

Thermal injury resulted in marked reduction in splenocyte proliferative response to T-cell mitogens, IL-2 production, and T-helper/suppressor cells (CD4/CD8) ratio. Prophylactic treatment with SDD significantly decreased the incidences of bacterial translocation and endotoxemia, prevented suppressive mitogenic response and inadequate IL-2 production (p < 0.05-0.01) but did not affect the abnormal ratio of CD4 to CD8 T lymphocytes in blood (p > 0.05).

CONCLUSIONS

These results suggest that bacteria/endotoxin translocation from the gut appears to be involved in cell-mediated immune dysfunction as a consequence of thermal injury. Pretreatment with SDD might attenuate postburn immunosuppression by preventing translocation events.

Central nervous system infection due to Clostridium septicum: a case report and review of the literature

A patient with end stage breast cancer was admitted to hospital due to fever, chills, multiply eroded discharging wounds, and sudden onset of left hemiparesis. Clostridium septicum bacteremia and brain abscess were diagnosed. The patient was treated successfully with intravenous penicillin and clindamycin and stereotactic aspiration of the abscess. Eleven cases of C. septicum central nervous system infection are reviewed. They showed an extremely fulminant course and high fatality. Nevertheless, some relationship seems to exist between outcome and type of brain lesion. Hemolytic-uremic syndrome associated with central nervous system infection is also discussed, because all these cases in the literature were due to this organism. Early diagnosis and aggressive treatment, including surgical drainage and appropriate antibiotics, are the key to improving the prognosis. A long-term prophylactic oral antimicrobial agent is suggested for patients who survive this infection.

Cultures of "Clostridium acetobutylicum" from various collections comprise Clostridium acetobutylicum, Clostridium beijerinckii, and two other distinct types based on DNA-DNA reassociation

The best-known acetone-butanol (solvent)-producing bacterium is the Weizmann organism, Clostridium acetobutylicum, which was used for starch-based industrial fermentation. In the past two decades, cultures of "C. acetobutylicum" from various culture collections have included organisms that were isolated for sugar (molasses)-based industrial solvent production. Recent biochemical and genetic studies have revealed significant differences among some of these "C. acetobutylicum" strains. We used DNA-DNA reassociation to analyze 39 cultures of "C. acetobutylicum" and phenotypically similar organisms from major collections. The results of this study clearly identified four groups intergroup reassociation values of less than 30%. All of the intragroup values except the value for one strain were 68% or more, which supported species status for each group. The C. acetobutylicum group (with ATCC 824 as the type strain) consisted of 17 cultures and had average reassociation values of 10% with the other three groups. All strains of C. acetobutylicum produced riboflavin in milk, and the cultures were bright yellow, which is useful for differentiating this species from the other three groups. The Clostridium beijerinckii group (with VPI 5481 [= ATCC 25752] as the type strain) consisted of 16 cultures and included strains NCIMB 8052 and NCP 270. Strains NCP 262 and NRRL B643 constituted the third group, whereas strain N1-4 ("Clostridium saccharoperbutylacetonicum") and its derivative, strain N1-4081, formed the fourth group. At present, the last two groups are each represented by only one independent strain; definitive descriptions of these two groups as two new or revived species will require further phenotypic characterization, as well as identification of additional strains. C. beijerinckii NCP 270, Clostridium sp. strain NRRL B643, and "C. saccharoperbutylacetonicum" were used in industrial solvent production from molasses, which confirms that the new organisms used for the sugar-based processes are distinct from C. acetobutylicum.