The epidemiology of patients with toxoplasmosis and its associated risk factors in Taiwan during the 2007-2020 period

BACKGROUND

Toxoplasmosis is a zoonotic parasitic disease caused by the protozoan Toxoplasma gondii (T. gondii), and may cause miscarriage and birth defects during pregnancy. This study aimed to assess the epidemiological features, epidemic trends, and correlations between the before number of confirmed toxoplasmosis cases in Taiwan from 2007 to 2020 in gender, age, season, and residential area, and hypothesized the environmental and climate factors also might affect the disease in Taiwan.

METHODS

This study reviewed publicly available annual summary data on reported toxoplasmosis cases in the Taiwan Centers for Diseases Control (TCDC) between 2007 and 2020.

RESULTS

This study collected 150 confirmed domestic and nine patients with imported toxoplasmosis. There was an increasing trend in the incidence of toxoplasmosis, 0.09-0.89 cases per 1,000,000 people, peaking in 2017. The average annual toxoplasmosis incidence was 4.4, 13, and 18 during 2007-2011, 2012-2016, and 2017-2020, respectively. Comparing sex, age, season, and place of residence, the incidence rate was highest in male, 20-39 years-old patients, summer, and the eastern region, with 1.02, 1.72, 0.38, and 3.63 cases per million population, respectively. Additionally, comparing the distribution of cases by age group in Taiwan, there were significant differences between 40-59 years-old in the northern region (odds ratio (OR) = 0.343, 95% confidence interval (CI) = 0.167-0.705, p = 0.004) and 40-59 years-old in the southern region (OR = 4.488, and 95% CI = 2.149-9.374, p< 0.001), respectively. Linear regression analysis also showed that PM (particulate matter) 2.5 (μg/m3) concentration was positively associated with toxoplasmosis (β = 0.095, p = 0.037). CO concentration was negatively correlated with toxoplasmosis (β = -14.001, p = 0.021).

CONCLUSIONS

This study is the first to report domestic and confirmed cases of imported toxoplasmosis from the surveillance data of the TCDC between 2007 and 2020. It identified that residence and age were associated with an increased risk of toxoplasmosis in Taiwan. This study confirmed that toxoplasmosis remains a prevalent infectious disease in Taiwan, its epidemic is gradually increasing and becoming more severe. These findings might be useful for policy-makers and clinical experts to direct prevention and control activities to patients with T. gondii, which causes the most severe illness and greatest burden to Taiwanese people.

Epidemiological features and risk factors for measles and rubella in Taiwan during 2011 to 2020

The risk of geographic transmission of infectious diseases due to air travel varies greatly. Our aim is to survey empirical data that provide a retrospective historical perspective on measles and rubella. This study used the open data website provided by the Taiwan Centers for Disease Control (TCDC) to extract the reported numbers of measles and rubella case between 2011 and 2020. There were 306 cases of measles and 135 cases of rubella. The incidence of measles and rubella per million population were 0 to 6.0 and 0 to 2.6, respectively. There was a gradual increase in the numbers of cases in those aged 20-39 years, and distinct duration patterns. It indicated that the risk of contracting rubella has significantly decreased in the last 5 years. Measles cases aged 20 to 39 years accounted for 72.5% of all cases. Rubella cases aged 20 to 39 years accounted for 59.3% of all cases. The male and residency in the Taipei metropolitan area or northern area were identified as potential risk factors for measles and rubella. Coverage with the first dose of the measles, mumps and rubella (MMR) vaccine in Taiwan increased from 97.31% to 98.86%, and the uptake rate of the second dose of the MMR vaccine increased from 95.73% to 98.39% between 2010 and 2020. Furthermore, the numbers of imported cases of measles (n = 0) and rubella (n = 0) reported during the coronavirus disease 2019 (COVID-19) pandemic were lower than those from 2011 to 2019. Measles and rubella cases were imported most frequently from Cambodia and Vietnam. This study represents the first report of confirmed cases of acquired measles and rubella from surveillance data of the TCDC between 2011 and 2020, also demonstrates that the numbers of cases of measles and rubella significantly decreased in Taiwan during the COVID-19 pandemic.

Epidemiology and risk factors for notifiable Clostridium botulinum infections in Taiwan from 2003 to 2020

Botulinum toxin is produced by Clostridium botulinum, a gram-positive anaerobic bacterium. This study aimed to examine the epidemiological characteristics, including sex, age, season in which infection occurred, place of residence, and epidemiological trends, of confirmed botulism cases in Taiwan from 2003 to 2020. This study examined the annual summary data on reported botulism in Taiwan' s Center for Disease Control from 2003 to 2020 available to the public on the internet. We found that there were 50 confirmed domestic cases of botulism. The incidence of botulism ranged from 0 to 0.48 per 1000,000 from 2003 to 2020 and peaked in 2008 and 2010. During the 18-year investigation period in which 6-year intervals were used, the study results showed a decreasing trend (2003-2008, 2009-14, and 2015-2020, had 22, 19, 9 cases each). In terms of patients' gender, age, and place of residence, most of the patients were females (56%), were aged ≥ 50 years (48%), and resided in Taipei and northern Taiwan (44%). The number of botulism cases in Taiwan from 2012 to 2020 compared with other years (from 2003 to 2011) found that there were significant differences among patients within an age group of <20 years (P = .003, odds ratio = 18.500, and 95% confidence interval = 3.287-104.111), and there were significant differences among patients whose place of residence was Taipei metropolitan area (P = .025, odds ratio = 5.667, and 95% confidence interval = 1.248-25.734). During 2003 to 2009, there was no case of botulism among those aged <20 years. Over the last 10 years, botulism in children showed an increasing trend. A total of 9 children were found to have botulism during 2010 to 2020; most of these children were male (66.7%) and were infected during spring and summer (66.7%). This study is the first to report the number of confirmed domestic cases with botulism from surveillance data from Taiwan's Center for Disease Control during 2003 to 2020. This study also found that the place of residence and age were associated with an increased risk of botulism in Taiwan. This information may be useful for policymakers and clinical experts to direct prevention- and control-based activities regarding botulism that result in the most severe illness and the greatest burden on Taiwanese.

Incidence and Risk Factors for Notifiable Typhoid and Paratyphoid in Taiwan during the Period 2011-2020

The risk of the geographic transmission of emerging infectious diseases through air travel varies greatly. In this study, we collected data on cases of food-borne diseases between the years 2011 and 2020 in Taiwan to access the epidemiological features, differences, and trends in domestic and imported cases of typhoid and paratyphoid in terms of patient sex, age, month of confirmation, and area of residence. In this study, we made use of the open data website provided by Taiwan’s Centers for Disease Control (TCDC) to extract the reported numbers of cases of typhoid and paratyphoid between January and December from 2011 to 2020 for comparison. Univariate analysis was performed using the Chi-square test for categorical variables. Fisher’s exact test was performed if an expected frequency was less than 5. A total of 226 typhoid cases and 61 paratyphoid cases were analyzed from the database. The incidences of typhoid and paratyphoid per million of the population were 0.42–2.11 and 0–0.39, respectively. There was a significant difference in the incidence of the diseases between the age groups (p = 0.019), with a gradual increase in the 20–40 years group. A distinct seasonal (between fall and spring) variation was also observed (p = 0.012). There were 34 cases of children with typhoid in the period 2011–2015 and 12 cases of children with typhoid in the period 2016–2020. During these periods, there were two cases of paratyphoid. This study indicated that the risk of children suffering from typhoid has been significantly reduced in the last five years. Furthermore, we found that more women have acquired typhoid and paratyphoid than men, and that living in the Taipei metropolitan area and the northern area was a potential risk factor. Furthermore, the number of imported cases of typhoid (n = 3) and paratyphoid (n = 0) reported during the COVID-19 pandemic was lower than that reported for the same disease from 2011 to 2020. More typhoid and paratyphoid cases were imported from Indonesia, India, Myanmar, and Cambodia. This study represents the first report on confirmed cases of acquired typhoid and paratyphoid from surveillance data from Taiwan’s CDC for the period 2011–2020. This study also demonstrates that the cases of typhoid and paratyphoid decreased in Taiwan during the COVID pandemic. Big data were used in this study, which may inform future surveillance and research efforts in Taiwan.

An unusual case of reactivated latent pulmonary cryptococcal infection in a patient after short-term steroid and azathioprine therapy: a case report

BACKGROUND

Cryptococcus is one of the major fungal pathogens infecting the lungs. Pulmonary cryptococcal infection is generally considered a community-acquired condition caused by inhalation of dust contaminated with fungal cells from the environment. Here, we report a case developing pulmonary cryptococcosis 3 months after hospital admission, which has rarely been reported before.

CASE PRESENTATION

A 73-year-old female patient who was previously immunocompetent experienced persistent dry cough for 2 weeks, 3 months after admission. Chest computed tomography (CT) showed a new solitary pulmonary nodule developed in the upper lobe of the left lung. Staining and culture of expectorated sputum smears were negative for bacteria, acid-fast bacilli, or fungus. The patient then underwent biopsy of the lesion. Histopathology findings and a positive serum cryptococcal antigen titer (1:8) indicated pulmonary cryptococcosis. Daily intravenous 400 mg fluconazole was administered initially followed by oral fluconazole therapy. Follow-up chest CT after 3 months of antifungal therapy showed complete disappearance of the pulmonary nodule. Respiratory symptoms of the patient also resolved. A complete investigation excluded the possibility of a patient-to-patient transmission or primarily acquiring the infection from the hospital environment. Based on the patient's history of exposure to pigeons before admission and recent steroid and azathioprine use after admission for the treatment of myasthenic crisis, reactivation of a latent pulmonary cryptococcal infection acquired before admission, in this case, is impressed.

CONCLUSIONS

Although rarely reported, pulmonary cryptococcal infection should be included in the differential diagnosis of hospitalized patients with respiratory symptoms, especially in those with predisposing risk factors. Chest image studies and further surgical biopsy are needed for confirmation.

Low pretreatment PNI correlates with worse survival in patients with stage III/IV NSCLC who received chemotherapy

The aim of this study was to investigate the prognostic value of the prognostic nutritional index (PNI) on the long-term survival of non-small cell lung cancer (NSCLC) patients who received platinum-based chemotherapy. Data on nutritional parameters and clinicopathological characteristics [e.g., albumin, total protein, body mass index (BMI), eastern cooperative oncology group (ECOG) performance status, stage, pathology, treatment strategy] were analyzed and retrospectively correlated with overall survival (OS). The PNI was calculated based on the concentration of albumin and lymphocyte count [10 × albumin, (g/dl) + 0.005 × lymphocyte (count/mm3)]. A receiver operating characteristic curve (ROC) analysis was used to find the optimal cut-off value of PNI. Univariate and multivariate analyses were used to evaluate the prognostic value of PNI. A total of 186 patients met the inclusion criteria. The optimal cut-off value for PNI was 50.45. Compared with the parameters of the low PNI group (n=76), high PNI was significantly associated with adenocarcinoma type, stage III, better ECOG and comprehensive treatment modality. The univariate analysis demonstrated that OS was superior when PNI ≥50.45, albumin ≥35 g/l, platelet-lymphocyte ratio (PLR) ≥163 and ECOG <2, and when the patient received a comprehensive treatment modality. In the multivariate analysis, PNI, TNM stage and treatment strategy were identified as independent predictors of survival in this study. This retrospective study demonstrated that a low PNI was related to worse overall survival in patients with stage III/IV NSCLC who received platinum-based chemotherapy. These data provided a conceptual basis for further research on the clinical application of the PNI index for patients receiving chemotherapy for intermediate- and advanced-stage NSCLC.

A Novel Strategy of Laparoscopic Insufflation Rate Improving Shoulder Pain: Prospective Randomized Study

BACKGROUND

Laparoscopic surgery is the main trend method in a variety of surgical fields. Post-operative shoulder pain remains a bothersome issue although many surgical techniques have been applied to minimize it. A simple novel approach to reduce shoulder pain without adverse effects during and after laparoscopic surgery is desired.

METHODS

This prospective randomized controlled study was conducted to enroll a total of 140 patients to evaluate the efficacy of low flow rate (1 L/min) for induction followed by high flow rate (10 L/min) for maintaining 12 mmHg pneumoperitoneum (group A, n = 70) during laparoscopic cholecystectomy (LC), compared to the continuous high flow rate group (group B, n = 70) in postoperative shoulder pain and other clinical features. The 10-visual analog scale (VAS) was applied for the severity of shoulder pain and scores were obtained at 1, 6, 12, 24, and 48 h after LC.

RESULTS

There was no obvious difference in baseline characteristics as well as operative time, occurrence of bradycardia, or hospital stay between groups. The incidence of shoulder pain was not significantly different (group A 45.7% vs group B 48.6%, p = 0.866). However, the patients in group A with shoulder pain reported significantly less pain scores (p < 0.001) at 12 and 24 h after surgery, compared with those in group B.

CONCLUSIONS

Applying the strategy of low flow rate to induce pneumoperitoneum followed by high flow rate to maintain the pressure provides advantages to reduce the severity of shoulder pain for patients who underwent LC and then experienced shoulder pain.

Early Initiation of Post-Pyloric Feeding in Patients with Major Burns: Experience in Taiwan Formosa Water Park Dust Explosion Disaster

Early initiation of enteral nutrition improves clinical outcomes in critical patients with serious burns. Post-pyloric tube feeding is a valuable therapeutic option for severely burned patients with poor gastric emptying. How early post-pyloric feeding can be initiated to provide more benefits to patients has not yet been examined. A fire erupted at a recreational water park in New Taipei City, Taiwan, on June 27, 2015. The results of early initiation versus delayed post-pyloric feeding in severely burned patients in this mass-casualty incident were compared. Door-to-post-pyloric feeding time ≤ 24 h was considered as early post-pyloric feeding (EPF) and that > 24 h was considered as delayed post-pyloric feeding (DPF). Thirteen patients with severe burn injuries (> 40% of the total body surface area) were assigned to undergo either EPF (five patients) or DPF (eight patients). This study is a "fortuitously controlled" study, and the authors were able to formulate and test whether EPF is better than DPF by comparing the two groups. In patients in the EPF, the intake of calories increased rapidly and was maintained throughout the study period. In addition, rapid restoration of plasma magnesium concentrations as well as pronounced recovery of platelet count in the EPF group was observed. In conclusion, our findings indicate that the time from injury to the onset of post-pyloric feeding is crucial, and EPF allows for the administration of calculated caloric needs. Therefore, EPF can be successfully initiated with beneficial outcomes of nutritional reconstruction in severely burned patients.

Is a bleeding scan prior to single-balloon enteroscopy necessary in patients with obscure gastrointestinal bleeding?

BACKGROUND/PURPOSE

To evaluate the efficacy and accuracy of bleeder localization in a pre-enteroscopic bleeding scan in patients with obscure gastrointestinal bleeding (OGIB).

METHODS

From January 2009 to December 2014, 98 patients with OGIB undergoing single-balloon enteroscopy (SBE) were enrolled. These patients were classified based on their history of a previous bleeding scan; 56 patients had undergone a previous bleeding scan, whereas 42 had not. The clinical characteristics, endoscopic findings, and rebleeding rate were compared between these two groups. The ability of the bleeding scan to localize the bleeding site was analyzed.

RESULTS

The mean age of patients was 56 ± 22 years; final diagnostic yield, 65.3%; and the most common etiology of OGIB, angiodysplasia (29.6%). There was no significant difference in demographic characteristics, OGIB etiologies, and final diagnostic yields (67.9% vs. 61.2%, bleeding scan vs. control group) between groups. In the bleeding scan group, the rate of positive detection was approximately 80.4%. However, only 26.7% patients with a positive bleeding scan showed correct localization of bleeding. Moreover, the bleeding scan delayed SBE (8.9 days vs. 3.0 days, p < 0.001). During the 24 months of follow-up, 15 patients (15.3%) exhibited rebleeding and needed to be hospitalized, but there was no significant difference between the groups.

CONCLUSION

In our study, bleeding scans in patients with OGIB revealed poor localization of the bleeder and delay in performing SBE. Thus, a bleeding scan prior to SBE showed a limited role for patients with OGIB.

Clinical characteristics and risk factors of active bleeding in colonic angiodysplasia among the Taiwanese

BACKGROUND

Colonic angiodysplasia (AGD) is a common cause of gastrointestinal bleeding. However, information on the characteristics and prevalence of colonic AGD is limited. We determined the clinical features of and risk factors for active bleeding in colonic AGD in a Taiwanese population.

METHODS

From February 2007 to December 2016, 13,047 patients undergoing 16,760 colonoscopies at the Tri-Service General Hospital were included in this study. Eighty-four patients were diagnosed with AGD. We conducted a retrospective study by analyzing the medical records of these patients. The clinical features and endoscopic findings were evaluated. Furthermore, we distinguished colonic AGD into bleeding and non-bleeding types and identified the risk factors for bleeding in colonic AGD.

RESULTS

In our study, the prevalence of colonic AGD was 0.6% among all patients who received colonoscopy. Among patients with colonic AGD, we found that many were aged; in all, 58.3% of patients with colonic AGD were older than 65 years. More than half of the patients had hypertensive cardiovascular disease (53.6%) and the AGD lesions were predominantly located in the left-sided colon (41.7%). We analyzed several factors to identify those associated with bleeding colonic AGD. Our results indicated that age (p < 0.001), hypertension (p = 0.020), atrial fibrillation (p = 0.027), and in-patient status (p = 0.006) were significant factors associated with active bleeding lesions. On multivariate analysis, old age was the only significant risk factor.

CONCLUSION

Angiodysplastic lesions in Taiwanese patients were predominantly identified in the left-sided colon. Old age was an independent risk factor associated with active bleeding in colonic angiodysplasia.

Nanoscale Removal of Picosecond Laser Ablation for Polymer

This paper analytically investigates the picosecond laser ablation of polymer. Laser-pulsed ablation is a well-established tool for polymer. However the ablation mechanism of laser processing for polymer has not been thoroughly understood yet. This study utilized a thermal transport model to analyze the relationship between the ablation rate and laser fluences. This model considered the energy balance at the decomposition interface as the ablation mechanisms and is applied to predict the laser-ablated depth of Acrylonitrile Butadiene Styrene/PolyVinyl Chloride (ABS/PVC). The calculated variation of the ablation rate with the logarithm of the laser fluence agrees with the measured data. The effects of material properties and processing parameters on the ablation depth per pulse are discussed for picosecond laser processing of ABS/PVC.

Clinical features and outcomes of gastric neuroendocrine tumors after endoscopic diagnosis and treatment: A Digestive Endoscopy Society of Tawian (DEST)

Gastric neuroendocrine tumors (GNETs) are a heterogeneous group of neoplasm with varying biological characteristics. This study aimed to investigate the clinical features and outcomes of GNET patients after endoscopic diagnosis and treatment in a multicenter registry. Patients with GNETs confirmed histologically were recruited from 17 hospitals between January 2010 and April 2016 in Taiwan. Clinical, laboratory, radiological, endoscopic, pathological data, treatment strategies, follow-up periods, and survivals were collected retrospectively. Totally 187 (107 female, 80 male) patients were recruited. Mean ( ± standard deviation [SD]) age and size of tumors were 63.2-year-old ( ± 14.6) and 2.3-cm ( ± 3.0). World Health Organization (WHO) grading were 93 (49.7%) G1, 26 (13.9%) G2, 40 (21.4%) G3, and 28 (15.0%) unknown. G3 patients were older (mean ± SD, 71.6 ± 12.4 vs. 60.9 ± 14.3/56.7 ± 15.4 years), larger (6.1 ± 4.0 vs.1.2 ± 1.3/2.4 ± 2.5 cm), more distally located (35.0% vs. 7.6%/15.4%), lower proportion of superficial lesions (17.5% vs. 61.9%/53.8%) and higher rates of lymphovascular invasion (32.5% vs. 3.2%/7.7%) than G1/G2. There was no nodal or distant organ metastases despite different grading of lesions≦10 mm and those <20 mm limited to mucosa and submucosa layers. GNETs larger than 20 mm with G1, G2, and G3 had lymph node (LN) metastatic rates of 21.4%, 30.0%, and 59.3%, respectively. Survivals were different between grading for those >20 mm (log-rank test P = .02). Male gender (P = .01), deeper invasion (P = .0001), nodal (P < .0001), and distant organ metastases (P = .0001) were associated with worse outcome. In conclusion, treatment strategies for GNET should be decided by grading, size, invasiveness, and LN metastasis risk. Curative endoscopic resection is feasible for G1/2 lesions less than 20 mm and limited to mucosa/submucosa layers without lymphovascular invasion.

Long-term outcomes in elderly patients with resectable large hepatocellular carcinoma undergoing hepatectomy

BACKGROUND

In contrast to the feasibility of hepatectomy for resectable large hepatocellular carcinoma (HCC, >5 cm) in the younger patients, the concerns of benefits for the elderly patients remain in practice. This study aimed to evaluate the long-term outcomes and safety after hepatectomy in elderly patients with resectable large HCC compared with younger patients.

METHODS

Between 2003 and 2014, a total of 2211 HCC patients were reviewed using a prospective database and 257 patients with resectable large HCC undergoing hepatectomy were included: 79 elderly patients with age ≥70 years and 178 younger patients with age <70 years. The last follow-up was assessed in December 2017. The complications, long-term outcomes and risk factors of disease-free and overall survival were analysed.

RESULTS

The 1-, 3-, 5- and 7-year overall survival rates in the elderly and younger groups were 76%, 55%, 48%, and 42% and 79%, 57%, 51%, and 49%, respectively (P = 0.319). The 1-, 3-, 5-, and 7-year disease-free survival rates in the elderly and younger groups were 60%, 40%, 38%, and 27% and 54%, 36%, 32%, and 32%, respectively (P = 0.633). The analysis of post-operative outcomes of interest, including hospital stay and hospital death and hepatectomy-related complications in both groups revealed no significant difference. Serum albumin and AJCC TNM stage were independent risk factors for survival. Serum alpha-fetoprotein, tumour number and AJCC TNM stage predicted HCC recurrence.

CONCLUSIONS

Our results suggested that hepatectomy can achieve comparable long-term outcomes in the selected younger and elderly patients with resectable large HCC.

Analysis for Heat Transfer in a High Current-Passing Carbon Nanosphere Using Nontraditional Thermal Transport Model

This paper investigates the thermal transport in hollow microscale and nanoscale spheres subject to electrical heat source using nontraditional thermal transport model. Working as supercapacitor electrodes, carbon hollow micrometer- and nanometer-sized spheres needs excellent heat transfer characteristics to maintain high specific capacitance, long cycle life, and high power density. In the nanoscale regime, the prediction of heat transfer from the traditional heat conduction equation based on Fourier's law deviates from the measured data. Consequently, the electrical heat source-induced heat transfer characteristics in hollow micrometer- and nanometer-sized spheres are studied using nontraditional thermal transport model. The effects of parameters on heat transfer in the hollow micrometer- and nanometer-sized spheres are discussed in this study. The results reveal that the heat transferred into the spherical interior, temperature and heat flux in the hollow sphere decrease with the increasing Knudsen number when the radius of sphere is comparable to the mean free path of heat carriers.

Isolated gastric variceal bleeding caused by splenic lymphoma-associated splenic vein occlusion

Isolated gastric varices (IGV) can occur in patients with left-sided portal hypertension resulting from splenic vein occlusion caused by thrombosis or stenosis. In left-sided portal hypertension, blood flows retrogradely through the short and posterior gastric veins and the gastroepiploic veins, leading to the formation of an IGV. The most common causes of splenic vein occlusion are pancreatic diseases, such as pancreatic cancer, pancreatitis, or a pseudocyst. However, various other cancers, such as colon, gastric, or renal cancers, have also been known to cause splenic vein occlusion. Our patient presented with a rare case of IGV bleeding induced by splenic lymphoma-associated splenic vein occlusion. Splenectomy, splenic artery embolization, and stenting of the splenic vein are the current treatment choices. Chemotherapy, however, is an alternative effective treatment for splenic vein occlusion caused by chemotherapy-sensitive tumors. Our patient responded well to chemotherapy with a cyclophosphamide, hydroxydaunorubicin, oncovin, and prednisolone regimen, and the splenic vein occlusion resolved after the lymphoma regressed.

Alkaptonuria - more than meets the eye

An elderly gentleman with chronic lower back and bilateral knee pain was found to have clinical and radiographic findings consistent with alkaptonuria. Diagnosis was confirmed by the detection of elevated homogentisic acid level in the urine using gas chromatography-mass spectrometry.

Thalidomide attenuates graft arteriosclerosis of aortic transplant in a rat model

OBJECTIVE

The purpose of the current study was to evaluate the effects of thalidomide on graft arteriosclerosis.

MATERIALS AND METHODS

Male Lewis rats received abdominal aorta grafts from male Brown-Norway rats. The animals were divided into 4 groups: no treatment controls, a low-dose group that received thalidomide (50 mg/kg per day), a middle dose group that received thalidomide (100 mg/kg per day), and a high-dose group that received thalidomide (200 mg/kg per day) by daily intragastric administration. Rats were humanely killed at 60 days after surgery. The grafted aortas were analyzed by histology, immunohistochemistry, and Western blot analysis. The serum was analyzed by an enzyme-linked immunosorbent assay (ELISA).

RESULTS

The neointimal thickness of the thalidomide treated aortas was significantly thinner compared with that of no treatment aortas (P < .05). Vascular endothelial growth factor (VEGF), platelet-derived growth factor, and intracellular adhesian molecule (ICAM-1) protein expression in the treatment group were significantly lower than those in the control group (P < .05). Moreover, thalidomide significantly inhibited the production of VEGF and ICAM-1 in serum (P < .05).

CONCLUSION

Our data suggested that thalidomide can attenuate graft arteriosclerosis so as to protect aortic grafts.

Causes of inpatient death for patients with warfare-related limb trauma and logistic regression analysis of the risk factors

OBJECTIVES

To explore the causes and risk factors of inpatient death for patients with warfare-related limb trauma.

METHODS

A retrospective study involving 339 patients with warfare-related limb trauma who were admitted to our hospital from 1998 to 2002 was conducted. Autopsy was performed for 15 cases who died in order to investigate the cause of death. Furthermore, based on the clinical features of warfare-related trauma patients, 11 factors were selected for further analysis: X1: causes of trauma, X2: shock after injury, X3: time from injury to hospital admission, X4: injured sites, X5: combined trauma (including head, thorax, abdomen, and vascular injury), X6: number of surgical procedures, X7: foreign body remaining, X8: fracture, X9: amputation, X10: duration of tourniquet homeostasis, X11: infection. All variables were available in all cases, and all parameters were quantified and fed into a computer. Multivariate statistical analysis was performed with a logistic regression model to elucidate the risk factors influencing death.

RESULTS

Fifteen of the 339 inpatient cases died (4.4%). The causes were primarily acute renal failure (ARF) (seven cases, 46.7%), pulmonary embolism (PE) (three cases, 20.0%), multiple organ system failure (MOSF) (two cases, 13.3%), and gas gangrene (three cases, 20.0%). There was one case of gas gangrene with concomitant ARF, and one of gas gangrene with MOSF. The primary risk factors influencing death included shock, amputation, and complicating infection (P < 0.05).

CONCLUSION

The primary cause of death from warfare-related limb trauma is ARF. The appropriate and prompt management of shock patients, the correct timing of amputation, and the prevention and correct handling of infection are important in reducing mortality.

Molybdenum cofactor deficiency in a Malaysian child

Molybdenum cofactor deficiency is a rare autosomal recessive disorder with devastating neurological manifestations, characterised by neonatal-onset encephalopathy mimicking hypoxic-ischaemic insult, intractable seizure, and feeding and respiratory difficulties. It is often fatal in the early life. We report an affected 8-year-old boy, who presented with severe neurological manifestations since birth, but without clinically-significant seizure. Molybdenum cofactor deficiency must be included in the differential diagnosis of patients presenting with unexplained encephalopathy in the newborn period, and whose neuroimaging findings are consistent with hypoxic ischaemic encephalopathy. The classic laboratory hallmark of this disorder is low serum uric acid, positive urine sulphite dipstick test, and elevated urinary S-sulphocysteine, hypoxanthine and xanthine.

Experimental study on genistein prevention and treatment of transplant arteriosclerosis in aortic transplants of rat

OBJECTIVE

Our objective was to study the effects of genistein, a soy isoflavone, on transplant arteriosclerosis, in addition to its immunosuppressive and antioxidant properties.

MATERIALS AND METHODS

We performed male Brown-Norway to male Lewis aortic transplantation. The recipients were randomly assigned to 3 groups: no treatment controls, dimethyl sulfoxide (DMSO; 5 mL/kg) solvent controls, and experimental group that received genistein (20 mg/kg/d) by daily intraperitoneal injection. On postoperative day 60, the graft was harvested and blood obtained. The transplanted aorta was analyzed by histology and immunohistochemistry. The serum was analyzed by an enzyme-linked immunosorbent assay (ELISA).

RESULTS

Compared with the 2 controls, leukocyte recruitment to the graft was significantly inhibited by genistein, with a profound reduction in the number of CD69 macrophages infiltrating the adventitia of the transplanted aortas. Moreover, genistein significantly inhibited the expression of VEGF and IFN-gamma production (P < .01).

CONCLUSION

These results suggested that the protein tyrosine kinase inhibitor genistein inhibited graft arteriosclerosis.

Magnesium supplementation prevents chronic cyclosporine nephrotoxicity via adjusting nitric oxide synthase activity

INTRODUCTION

Nitric oxide synthase (NOS) is a protective factor for chronic cyclosporine nephrotoxicity by virtue of adjusting the production of nitric oxide (NO). The aim of this study was to explore the role of NOS in the effect of magnesium supplementation to prevent chronic cyclosporine nephrotoxicity.

METHODS

Rats maintained on a low-salt diet were divided into three groups: normal controls, cyclosporine group (CsA 15 mg x kg(-1) x d(-1) subcutaneously) and CsA + Mg2+ group (CsA subcutaneously and dietary supplementation with 0.6% Mg enriched by MgCl2). On day 28, plasma Mg2+, plasma creatinine, NOS activity, and NO content in renal tissue were examined. The renal expression of endothelial nitric oxide synthase (eNOS) and inducible nitric oxide synthase (iNOS) in kidneys was determined by an immunohistochemistry technique. The lesions of chronic cyclosporine nephrotoxicity were identified by HE and PAS stains as well as electron microscope.

RESULTS

After 28 days of CsA administration, characteristic histological lesions of chronic cyclosporine nephotoxicity were observed, including arteriolopathy, tubular atrophy and interstitial fibrosis. Giant mitochondria and microcalcifications were observed by electron microscopy. Simultaneously, constitutive nitric oxide synthase (cNOS) activity in kidneys was increased, but NO content did not increase correspondingly (P < .05) compared with normal controls. Dietary supplementation with Mg2+ ameliorated the CsA-induced histological lesions. cNOS activity was decreased to normal levels and NOS was increased (P < .05) compared with animals that only received CsA. CsA and magnesium supplementation did not change iNOS activity.

CONCLUSIONS

Dietary supplementation with Mg2+ seems to improve renal function and almost abolish CsA-induced histological lesions via altering the abnormal activation of cNOS in this model.

Inhibition of MD-1 expression by immunosuppressants or antisense oligodeoxynucleotides on skin allograft survival in mice

AIM

The aim of this study was to investigate the effects of inhibition of MD-1 expression using nonspecific immunosuppressants and specific antisense oligodeoxynucleotides (AS-ODNs) treatment on skin allograft survival in mice.

METHODS

C57BL/6 to Balb/c skin allograft model was used in all groups, followed by Cyclosporine (CsA), Tacrolimus (FK506), Mycophenolate Mofetil (MMF), and Sirolimus (SRL) intraperitaneally, as well as AS-ODNs intravenously. Recipients were humanely killed at 11 days after transplantation. MD-1 expression was determined using flow cytometric analysis (FACS). AlamarBlue was used to evaluate proliferation. And serum levels of interleukin (IL)-2 and IL-10 were detected using enzyme-linked immunosorbent assay (ELISA).

RESULTS

Compared with saline controls, the mean survival times (MST) of skin allografts in all of the immunosuppressants and AS-ODNs treated groups were significantly prolonged (P < .05). CsA, MMF, and AS-ODNs inhibited MD-1 expression and lymphocyte proliferation, as well as decreased serum level of IL-2 and increased that of IL-10; FK506, treatment showed all the effects mentioned above but up-regulated the IL-10 level; SRL had no significant influence on either MD-1 expression or IL-2 and IL-10 level, although it equally suppressed the proliferation (P < .05 vs controls). The negative correlation between MD-1 expression and lymphocyte proliferation or IL-2 level was significant, as was the positive correlation between it and IL-10 level (P < .01).

CONCLUSIONS

CsA, FK506, MMF, and AS-ODNs can efficiently inhibit MD-1 expression. The effects of the immunosuppressants are seemingly associated with the down-regulation of the IL-2 serum level. MD-1 was theorized to play an important role in rejection promotion, although the precise relationship between it and allograft survival still remains ambiguous.

Effects of Ginsenoside Rb2 and Rc on inferior human sperm motility in vitro

The purpose of the study was to investigate the effects of two constituents of Panax notoginseng flower extract, Ginsenoside Rb2 and Rc, on human sperm motility and progression in vitro. Semen samples were collected from 20 patients with sperm motility between 20% and 40% of normal. All samples had sperm counts of over 20 million per milliliter, in accordance with the World Health Organization standard. Sperm were separated by a Percoll discontinuous gradient technique, and divided into a Percoll sperm control group, and three Ginsenoside Rb2 experimental groups (0.1, 0.01 and 0.001 mg/ml) and three Ginsenoside Rc experimental groups (0.1, 0.01 and 0.001 mg/ml). The results showed that at concentrations of 0.01 mg/ml and 0.001 mg/ml, Ginsenoside Rc enhanced both sperm motility and sperm progression significantly at the end of the 1st and 2nd hour. However, the three concentrations of Ginsenoside Rb2 did not increase sperm motility at the 1st or 2nd hour, but promoted sperm progression at the 2nd hour, when compared to the Percoll group.

Arylcyclopropanecarboxyl guanidines as novel, potent, and selective inhibitors of the sodium hydrogen exchanger isoform-1

A novel series of arylcyclopropanecarboxyl guanidines was synthesized and evaluated for activity against the sodium hydrogen exchanger isoform-1 (NHE-1). In biological assays conducted in an AP1 cell line expressing the human NHE-1 isoform, the starting cyclopropane 3a (IC(50) = 3.5 microM) shows inhibitory activity comparable to cariporide (IC(50) = 3.4 microM). Structure-activity relationships are used to optimize the affinity of various acyl guanidines for NHE-1 by screening the effect of substituents at both aryl and cyclopropyl rings. It is demonstrated that introduction of appropriate hydrophobic groups at the phenyl ring and a gem-dimethyl group at the cyclopropane ring enhances the NHE-1 inhibitory activity by up to 3 orders of magnitude (compound 7f, IC(50) = 0.003 microM). In addition, the gem-dimethyl series of analogues seem to display improved oral bioavailability and longer plasma half-life in rats. Furthermore, the lead benzodihydrofuranyl analogue 1 (BMS-284640) shows over 380-fold increased NHE-1 inhibitory activity as well as improved selectivity for NHE-1 over NHE-2 compared to cariporide.

Executive function deficits in non-retarded autistic children

The purpose of this study was to examine differences between Taiwanese children with autism and their typically developing peers on the Wisconsin Card Sorting Test (WCST). Twenty-six children with autism of normal IQ were included, and matched for chronological age with 52 controls. The WCST scores of the typically developing children were significantly higher for categories completed and percent conceptual level than in the autism group. Scores on perseverative responses, perseverative errors, the number of trials to complete the first category and non-perseverative errors were significantly higher in the autism group. The implications of these findings are discussed.

Involvement of protein kinases in the potentiation of lipopolysaccharide-induced inflammatory mediator formation by thapsigargin in peritoneal macrophages

We have explored the regulatory roles played by Ca2+-dependent signaling on lipopolysaccharide (LPS)-induced nitric oxide (NO), prostaglandin E2 (PGE2), tumor necrosis factor alpha (TNF-alpha), and interleukin-6 (IL-6) release in mouse peritoneal macrophages. To elevate intracellular Ca2+, we used thapsigargin (TG) and UTP. Although LPS alone cannot stimulate NO synthesis, co-addition with TG, which sustainably increased [Ca2+]i, resulted in NO release. UTP, via acting on P2Y6 receptors, can stimulate phosphoinositide (PI) turnover and transient [Ca2+]i increase, however, it did not possess the NO priming effect. LPS alone triggered the release of PGE2, TNF-alpha, and IL-6; all of which were potentiated by the presence of TG, but not of UTP. The stimulatory effect of LPS plus TG on NO release was inhibited by the presence of Ro 31-8220, Go6976, KN-93, PD 098059, or SB 203580, and abolished by BAPTA/AM and nuclear factor kappaB (NF-kappaB) inhibitor, PDTC. PGE2, TNF-alpha, and IL-6 release by LPS alone were attenuated by Ro 31-8220, Go6976, PD 098059, SB 203580, and PDTC. Using L-NAME, soluble TNF-alpha receptor, IL-6 antibody, NS-398, and indomethacin, we performed experiments to understand the cross-regulation by the four mediators. The results revealed that TNF-alpha up-regulated NO, PGE2, and IL-6 synthesis; PGE2 up-regulated NO, but down-regulated TNF-alpha synthesis; and PGE2 and IL-6 mutually up-regulated reciprocally. Taken together, murine peritoneal macrophages required a sustained [Ca2+]i increase, which proceeds after TG, but not UTP, stimulation, to enhance LPS-mediated release of inflammatory mediators, particularly for NO induction. Activation of PKC-, ERK-, and p38 MAPK-dependent signaling also are essential for LPS action. The positive regulatory interactions among these mediators might amplify the inflammatory response caused by endotoxin.

Quantitation of cerivastatin and its seven acid and lactone biotransformation products in human serum by liquid chromatography-electrospray tandem mass spectrometry

A method for the simultaneous quantitation of cerivastatin (acid) and its biotransformation products, cerivastatin lactone, M-1 (acid), M-1 lactone, M-23 (acid), M-23 lactone, M-24 (acid) and M-24 lactone, in human serum by high-performance liquid chromatography (LC) with positive ion electrospray tandem mass spectrometry (MS-MS) was developed and validated. The method involves extraction of cerivastatin and its biotransformation products from acidified human serum (0.5 ml) using methyl tert.-butyl ether. The standard curve ranges in human serum were from 0.0100 to 10.0 ng/ml for cerivastatin and cerivastatin lactone, 0.0500 to 10.0 ng/ml for M-1 (acid) and M-1 lactone, 0.100 to 10.0 ng/ml for M-23 (acid) and M-23 lactone, and 0.500 to 10.0 ng/ml for M-24 (acid) and M-24 lactone. The lactone compounds in human serum at room temperature underwent considerable conversion to the corresponding acid compounds after only 4 h. Lowering the serum pH with a pH 5.0 buffer stabilized the lactone compounds for up to 24 h at room temperature. The degree of lactonization of the acid compounds was < or = 3.5% and the degree of hydrolysis of the lactone compounds was < or = 6.0% during the entire assay procedure. All the eight analytes eluted within 2.0 min and the total run time was only 3.5 min.

Potentiation of lipopolysaccharide-induced IL-6 release by uridine triphosphate in macrophages: cross-interaction with cyclooxygenase-2-dependent prostaglandin E(2) production

Our previous study has demonstrated the potentiation by uridine triphosphate (UTP) of nitric oxide (NO) and prostaglandin E(2) (PGE(2)) production in lipopolysaccharide (LPS)-stimulated murine J774 macrophages. In this study, we found that the amount of interleukin-6 (IL-6) release in response to LPS stimulation was greatly enhanced in the presence of UTP. This enhancement exhibited concentration dependence and occurred after 8 h of treatment with LPS. RT-PCR analysis indicated that the steady-state level of IL-6 mRNA induced by LPS was apparently increased upon co-addition of UTP. The potentiation by UTP was inhibited by the treatment with U73122 (a phosphatidylinositol-phospholipase C inhibitor), BAPTA/AM (an intracellular Ca(2+) chelator), KN-93 (a selective inhibitor of calmodulin-dependent protein kinase) or PDTC (a nuclear factor kappaB inhibitor). To understand the cross-regulation among NO, PGE(2) and IL-6, all of which are dramatically induced after LPS stimulation, the effects of L-NAME (a nitric oxide synthase inhibitor), indomethacin (a cyclooxygenase inhibitor), NS-398 (a cycloxygenase-2 inhibitor) and IL-6 antibody were tested. The results revealed the positive regulation between PGE(2) and IL-6 synthesis because NS-398 and indomethacin inhibited LPS plus UTP-induced IL-6 release, and IL-6 antibody attenuated LPS plus UTP-induced PGE(2) release. Taken together these results reinforce the role of UTP as a regulatory element in inflamed sites by demonstrating the capacity of this nucleotide to potentiate LPS-induced release of inflammatory mediators.

Modulation of inducible nitric oxide synthase induction by prostaglandin E2 in macrophages: distinct susceptibility in murine J774 and RAW 264.7 macrophages

Prostaglandin E2 (PGE2) is the major cyclooxygenase metabolite in macrophages with complex proinflammatory and immunoregulatory properties. In the present study, we have compared the modulatory role of PGE2/cAMP-dependent signaling on induced nitric oxide (NO) production in two murine macrophages, J774 and RAW 264.7. With no effect on NO release by itself, PGE2 co-addition with lipopolysaccharide (LPS) resulted in a concentration-dependent enhancement in NO release and inducible NO synthase induction in J774, but not in RAW 264.7, macrophages. The potentiation effect of PGE2 in J774 cells was still seen when applied within 9 h after LPS treatment. Whereas RAW 264.7 macrophages release PGE2 with greater extent than J774 macrophages in response to LPS, indomethacin and NS-398, upon abolishing LPS-induced PGE2 release, caused a more obvious inhibition of NO release from J774 than RAW 264.7 cells. Thus, we suggest a higher positive modulatory role of PGE2--either endogenous or exogenous--on NO formation in J774 cells. Supporting these findings, exogenous PGE2 triggers cAMP formation in J774 cells with higher potency and efficacy. Of interest, dBcAMP also elicits higher sensitivity in potentiating NO release in J774 cells. We conclude that the opposite effect of PGE2/cAMP signaling on macrophage NO induction depends on its signaling efficacy and might be associated with the difference in endogenous PGE2 levels.

Enzymatic synthesis of L-6-hydroxynorleucine

L-6-Hydroxynorleucine, a key chiral intermediate used for synthesis of a vasopeptidase inhibitor, was prepared in 89% yield and > 99% optical purity by reductive amination of 2-keto-6-hydroxyhexanoic acid using glutamate dehydrogenase from beef liver. In an alternate process, racemic 6-hydroxynorleucine produced by hydrolysis of 5-(4-hydroxybutyl)hydantoin was treated with D-amino acid oxidase to prepare a mixture containing 2-keto-6-hydroxyhexanoic acid and L-6-hydroxynorleucine followed by the reductive amination procedure to convert the mixture entirely to L-6-hydroxynorleucine, with yields of 91 to 97% and optical purities of > 99%.

Protein kinase C epsilon-dependent pathway of extracellular signal-regulated protein kinase activation by P2Y1 and P2Y2 purinoceptors that activate cytosolic phospholipase A2 in endothelial cells

The aim of this study was to investigate the stimulating effects on arachidonic acid release of P2Y1 and P2Y2 receptor-selective agonists, 2-methylthio-ATP (2MeSATP) and UTP, respectively, in bovine pulmonary artery endothelial cells. Exposure of cells to 2MeSATP and UTP led to the release of arachidonic acid, a response which was abolished by the removal of extracellular Ca2+ and methyl arachidonyl fluorophosphonate. Phorbol 12-myristate 13-acetate (PMA) itself not only stimulated arachidonic acid release but also played a permissive role in the response to UTP. However, PMA failed to enhance the arachidonic acid response induced by 2MeSATP, probably due to greater attenuation of the [Ca2+]i increase caused by 2MeSATP than UTP. Inhibition of protein kinase C with Ro 31-8220 (1-[3-(amidinothio) propyl-1H-indoyl-3-yl]-3-(1-methyl-1H-indoyl-3-yl)-maleimide -methane sulphate) and staurosporine, but not with Go 6976 (12-(-2-cyanoethyl)-6,7,12,13-tetrahydro-13-methyl-5-oxo-indolo(2, 3-a)pyrrolo(3,4-c)carbazole), reduced the arachidonic acid response of 2MeSATP, UTP and PMA. PMA-induced potentiation of the UTP response reached a maximum after a 1-h preincubation, then declined and eventually lost its effect when the preincubation lasted up to 8 h. Among the protein kinase C isoforms present in endothelial cells, betaI and epsilon could be down-regulated by treatment with PMA for 4-24 h. PD 098059 (2-(2-Amino-3-methoxyphenyl)-4H-1-benzopyran-4-one) inhibited extracellular signal-regulated protein kinase activation, cytosolic phospholipase A2 phosphorylation and arachidonic acid release caused by 2MeSATP, UTP and PMA. Taken together, our results demonstrate that P2Y1 and P2Y2 purinoceptors mediate arachidonic acid release by activating cytosolic phospholipase A2 through an elevation of [Ca2+]i and protein kinase C epsilon-, extracellular signal-regulated protein kinase-dependent phosphorylation.

Induction of cyclo-oxygenase-2 expression by methyl arachidonyl fluorophosphonate in murine J774 macrophages: roles of protein kinase C, ERKs and p38 MAPK

1. Methyl arachidonyl fluorophosphonate (MAFP), an inhibitor of phospholipase A2 (PLA2), has been widely used to assess the roles of PLA2 in various cell functions. Here, we report on a novel action of this compound at concentrations similar to those used for PLA2 inhibition. 2. The murine macrophage J774 released a large amount of prostaglandin E2 (PGE2) by MAFP (1-30 microM), which was abolished by indomethacin and NS-398 but not by valeryl salicylate, and results from increased cyclo-oxygenase-2 (COX-2) protein levels and gene expression. 3. This PGE2 release was blocked by inhibitors of tyrosine kinase (genistein), protein kinase C (PKC) (Ro 31-8220, Go 6976 or LY 379196), mitogen-activated protein kinase kinase (MEK) (PD 098059) or p38 mitogen-activated protein kinase (MAPK) (SB 203580). 4. Consistent with these results, MAFP caused membrane translocation of PKCbetaI and betaII isoforms and activated extracellular signal-regulated kinase (ERK) and p38 MAPK. 5. In accordance with these effects of MAFP, PKC activator phorbol 12-myristate 13-acetate (PMA) increased PGE2 release and caused activation of PKCbeta, ERKs and p38 MAPK. 6. This is the first report that the PLA2 inhibitor, MAFP, can induce COX-2 gene expression and PGE2 synthesis via the PKC-, ERK- and p38 MAPK-dependent pathways. Thus, the use of MAFP as a PLA2 inhibitor should be treated with caution.

Quantitation of the acid and lactone forms of atorvastatin and its biotransformation products in human serum by high-performance liquid chromatography with electrospray tandem mass spectrometry

A method for simultaneous quantitation of both the acid and lactone forms of atorvastatin, a new synthetic inhibitor of HMG-CoA reductase that is being marketed for the treatment of high serum cholesterol, and both the acid and lactone forms of its two biotransformation products, 2-hydroxyatorvastatin and 4-hydroxyatorvastatin, in human serum (a total of six analytes) by high-performance liquid chromatography with electrospray tandem mass spectrometry was developed and validated. A deuterium labeled analog was used as internal standard for each of the six analytes. Each point of the calibration standard curve, which ranged from 0.5 to 200 ng/mL, contained the six analytes at equal concentrations. Three groups of quality control (QC) samples were used. In the first group, combination QC samples contained all six analytes at equal concentrations. In the second group, acid-only QC samples contained only the acid forms (i.e. three analytes) at equal concentrations. In the third group, lactone-only QC samples contained only the lactone forms (i.e. three analytes) at equal concentrations. After adding the internal standard to 0.5 mL of each standard and the QC sample kept at 4 degrees C, the samples were acidified with sodium acetate buffer (pH 5.0) and then extracted with methyl tert-butyl ether. Detection was by positive ion electrospray tandem mass spectrometry using eight selected reaction monitoring channels. The acid compounds were stable in human serum at room temperature but the lactone compounds were unstable as they hydrolyzed rapidly to their respective acid forms. The conversion of the lactone compounds in both QC and post-dose human serum samples was nearly complete after 24 h at room temperature. The lactone compounds in serum could be stabilized by lowering the working temperature to 4 degrees C or lowering the serum pH to 6.0. The acid-only and the lactone-only QC samples showed that, under the sample processing conditions used, the degree of the hydrolysis of the lactone compounds or the lactonization of the acid compounds during the assay procedure was minimal (< 5%). The intra-day C.V., inter-day C.V. and the deviations from the nominal concentrations for all six analytes were within 15%, demonstrating good precision and accuracy. The required lower limit of quantitation (LLQ) of 0.5 ng/mL was achieved for each analyte.

Distinct PKC isoforms mediate the activation of cPLA2 and adenylyl cyclase by phorbol ester in RAW264.7 macrophages

The modulatory effects of protein kinase C (PKC) on the activation of cytosolic phospholipase A2 (cPLA2) and adenylyl cyclase (AC) have recently been described. Since the signalling cascades associated with these events play critical roles in various functions of macrophages, we set out to investigate the crosstalk between PKC and the cPLA2 and AC pathways in mouse RAW 264.7 macrophages and to determine the involvement of individual PKC isoforms. The cPLA2 and AC pathways were studied by measuring the potentiation by the phorbol ester PMA of ionomycin-induced arachidonic acid (AA) release and prostagladin E1 (PGE1)-stimulated cyclic AMP production, respectively. PMA at 1 microM caused a significant increase in AA release both in the presence (371%) and absence (67%) of ionomycin induction, while exposure of RAW 264.7 cells to PMA increased PGE1 stimulation of cyclic AMP levels by 208%. Treatment of cells with staurosporine and Ro 31-8220 inhibited the PMA-induced potentiation of both AA release and cyclic AMP accumulation, while Go 6976 (an inhibitor of classical PKC isoforms) and LY 379196 (a specific inhibitor of PKCbeta) inhibited the AA response but failed to affect the enhancement of the cyclic AMP response by PMA. Long term pretreatment of cells with PMA abolished the subsequent effect of PMA in potentiating AA release, but only inhibited the cyclic AMP response by 42%. Neither PD 98059, an inhibitor of MEK, nor genistein, an inhibitor of tyrosine kinases, had any effect on the ability of PMA to potentiate AA or cyclic AMP production. The potentiation of AA release, but not of cyclic AMP formation, by PMA was sensitive to inhibition by wortmannin. This effect was unrelated to the inhibition of PKC activation as deduced from the translocation of PKC activity to the cell membrane. Western blot analysis revealed the presence of eight PKC isoforms (alpha, betaI, betaII, delta, epsilon, mu, lambda and xi) in RAW 264.7 cells and PMA was shown to induce the translocation of the alpha, betaI, betaII, delta, epsilon and mu isoforms from the cytosol to the cell membrane within 2 min. Pretreatment of cells with PMA for 2-24 h resulted in a time-dependent down-regulation of PKCalpha, betaI, betaII, and delta expression, while the levels of the other four PKC isozymes were unchanged after PMA treatment for 24 h. A decrease in the potentiation of AA release by PMA was observed, concomitant with the time-dependent down-regulation of PKC. These results indicate that PKCbeta has a crucial role in the mediation of cPLA2 activation by the phorbol ester PMA, whereas PMA utilizes PKC epsilon and/or mu to up-regulate AC activity.

Pyrimidinoceptor-mediated potentiation of inducible nitric-oxide synthase induction in J774 macrophages. Role of intracellular calcium

We have shown that, in murine J774 macrophages, binding of UTP to pyrimidinoceptors stimulates phosphoinositide (PI) breakdown and an increase in [Ca2+]i. In this study, UTP modulation of the expression of inducible nitric-oxide synthase (iNOS) was investigated. Although UTP alone had no effect, stimulation of J774 cells with a combination of UTP (10-300 microM) and LPS (0.1-3 microgram/ml) resulted in a potentiated increase in nitrite levels. In parallel, the amount of iNOS protein induced by LPS was also potentiated by UTP treatment. The UTP potentiating effect was attenuated by U73122, suggesting involvement of the downstream signaling pathways of phosphatidylinositide turnover. The tyrosine kinase inhibitor genistein inhibited both the LPS-induced nitrite response and the UTP potentiation. Conversely, two protein kinase C inhibitors, Ro 31-8220 and Go 6976, and a phosphatidylcholine-specific phospholipase C inhibitor, D609, inhibited LPS-stimulated nitrite induction, but did not affect the potentiating effect of UTP, which was also unaffected by pretreatment with phorbol 12-myristate 13-acetate for 8 h. Furthermore, the UTP-induced potentiation was abolished by BAPTA/AM or KN-93 (a selective inhibitor of Ca2+/calmodulin-dependent protein kinase (CaMK)). Nitrite potentiation and iNOS induction were prominent when UTP was added simultaneously with LPS, with the potentiating effect being lost when UTP was added 3 h after treatment with LPS. Pyrrolidinedithiocarbamate (3-30 microM), an inhibitor of NF-kappaB, caused a concentration-dependent reduction in the nitrite response to LPS and UTP. In electrophoretic mobility shift assays, LPS produced marked activation of NF-kappaB and AP-1, which was potentiated by UTP. LPS-induced degradation of IkappaB-alpha as well as the phosphorylation of IkappaB-alpha were also increased by UTP. Moreover, the UTP-potentiated activation of NF-kappaB and AP-1 and the degradation and phosphorylation of IkappaB-alpha were inhibited by KN-93. Taken together, these data demonstrate that nucleotides, especially UTP, can potentiate the LPS-induced activation of NF-kappaB and AP-1 and of iNOS induction via a CaMK -dependent pathway and suggest that the UTP-dependent up-regulation of iNOS may constitute a novel element in the inflammatory process.

Use of nonautologous microencapsulated fibroblasts in growth hormone gene therapy to improve growth of midget swine

The aim of the present study was to investigate the expression activity, both in vitro and in vivo, of the porcine growth hormone complementary DNA (pGH cDNA) in porcine fetal fibroblast (PFF) cells. The pGH gene had been constructed inside the bicistronic retroviral vector PSN and subsequently transfected into PFF cells further encapsulated with immunoprotective microcapsules. This would provide a way to evaluate the improvement in growth performance of Tao-Yuan swine by the use of nonautologous microencapsulated fibroblasts carrying the pGH cDNA via the technique of somatic gene therapy. Results from Southern blot analysis confirmed that the full length of the pGH cDNA was completely integrated into the genome of the PFF cells after they had been infected one to four times using a PSN retroviral vector. Moreover, Northern blot analysis showed that high transcription activity was present in clones infected twice, and exogenous pGH secretion was found when the pGH-infected PFF had been further cultured for 48 hr in vitro and subjected to immunoblot assay. Encapsulation of the pGH-PFF with an alginate-poly-L-lysine-alginate membrane did not show any deterioration in their proliferation and survival both in vitro and in vivo. The pGH gene in encapsulated recombinant fibroblasts was fully expressed after it had been transplanted into the peritoneal cavity of the Tao-Yuan swine, and reverse transcription-polymerase chain reaction (RT-PCR) analysis was performed on the microcapsules retrieved 1 month later. The feasibility of pGH gene therapy to improve midget Tao-Yuan swine growth enhancement is further supported by the fact that transplantation of the encapsulated recombinant fibroblast cells resulted in a much more significant increase in weight gain than in those swine in either the age-matched untreated control group or in those that had been transplanted with uncapsulated recombinant PFF cells (10.56 +/- 1.01 kg versus 6.95 +/- 0.94 and 5.27 +/- 1.30 kg; p < 0.05). These experimental data suggest that growth hormone gene therapy did provide an alternative approach for growth improvement in midget Tao-Yuan swine.

Pharmacological comparison of UTP- and thapsigargin-induced arachidonic acid release in mouse RAW 264.7 macrophages

1. Although stimulation of mouse RAW 264.7 macrophages by UTP elicits a rapid increase in intracellular free Ca2+ ([Ca2+]i), phosphoinositide (PI) turnover, and arachidonic acid (AA) release, the causal relationship between these signalling pathways is still unclear. In the present study, we investigated the involvement of phosphoinositide-dependent phospholipase C (PI-PLC) activation, Ca2+ increase and protein kinase activation in UTP-induced AA release. The effects of stimulating RAW 264.7 cells with thapsigargin, which cannot activate the inositol phosphate (IP) cascade, but results in the release of sequestered Ca2+ and an influx of extracellular Ca2+, was compared with the effects of UTP stimulation to elucidate the multiple regulatory pathways for cPLA2 activation. 2. In RAW 264.7 cells UTP (100 microM) and thapsigargin (1 microM) caused 2 and 1.2 fold increases, respectively, in [3H]-AA release. The release of [3H]-AA following treatment with UTP and thapsigargin were non-additive, totally abolished in the Ca2+-free buffer, BAPTA (30 microM)-containing buffer or in the presence of the cPLA2 inhibitor MAFP (50 microM), and inhibited by pretreatment of cells with pertussis toxin (100 ng ml(-1)) or 4-bromophenacyl bromide (100 microM). By contrast, aristolochic acid (an inhibitor of sPLA2) had no effect on UTP and thapsigargin responses. 3. U73122 (10 microM) and neomycin (3 mM), inhibitors of PI-PLC, inhibited UTP-induced IP formation (88% and 83% inhibition, respectively) and AA release (76% and 58%, respectively), accompanied by a decrease in the [Ca2+]i rise. 4. Wortmannin attenuated the IP response of UTP in a concentration-dependent manner (over the range 10 nM-3 microM), and reduced the UTP-induced AA release in parallel. RHC 80267 (30 microM), a specific diacylglycerol lipase inhibitor, had no effect on UTP-induced AA release. 5. Short-term treatment with PMA (1 microM) inhibited the UTP-stimulated accumulation of IP and increase in [Ca2+]i, but had no effect on the release of AA. In contrast, the AA release caused by thapsigargin was increased by PMA. 6. The role of PKC in UTP- and thapsigargin-mediated AA release was shown by the blockade of these effects by staurosporine (1 microM), Ro 31-8220 (10 microM), Go 6976 (1 microM) and the down-regulation of PKC. 7. Following treatment of cells with SK&F 96365 (30 microM), thapsigargin-, but not UTP-, induced Ca2+ influx, and the accompanying AA release, were down-regulated. 8. Neither PD 98059 (100 microM), MEK a inhibitor, nor genistein (100 microM), a tyrosine kinase inhibitor, had any effect on the AA responses induced by UTP and thapsigargin. 9. We conclude that UTP-induced cPLA2 activity depends on the activation of PI-PLC and the sustained elevation of intracellular Ca2+, which is essential for the activation of cPLA2 by UTP and thapsigargin. The [Ca2+]i-dependent AA release that follows treatment with both stimuli was potentiated by the activity of protein kinase C (PKC). A pertussis toxin-sensitive pathway downstream of the increase in [Ca2+]i was also shown to be involved in AA release.

Involvement of protein kinase C in the UTP-mediated potentiation of cyclic AMP accumulation in mouse J774 macrophages

1. We have investigated the effects of nucleotide analogues on cyclic AMP formation in mouse J774 macrophages and the mechanisms involved. 2. UTP, in the concentration range 0.1-100 microM, induced concentration-dependent potentiation of prostaglandin E1 (PGE1)-induced cyclic AMP formation, but had no effect on basal cyclic AMP formation. UDP showed an equal potency, while 2-methylthio ATP, alpha, beta-methylene ATP and beta,gamma-methylene ATP gave either a slight increase or had no effect at concentrations up to 100 microM. ATP, although 100 fold less effective than UTP, also caused cyclic AMP potentiation, but had no effect on agonist-stimulated or basal cyclic AMP levels. 3. The cyclic AMP potentiation effect of UTP correlated with increased [Ca2+]i and inositol phosphate (IP) formation over the same concentration range. 4. Ionomycin, which evokes an increase in [Ca2+]i without affecting IP formation, did not cause an increase in cyclic AMP content, indicating that UTP-induced cyclic AMP regulation is not due to activation of Ca(2+)-sensitive adenylyl cyclase isoforms. 5. Although reduced, UTP potentiation was seen in cells incubated in a Ca(2+)-free and/or BAPTA-containing medium. Under these conditions, the UTP-increased IP accumulation was similarly reduced. 6. Exposure of cells to phorbol 12-myristate 13-acetate (PMA) also increased PGE1 stimulation of cyclic AMP levels, and the UTP-induced potentiation of cyclic AMP formation was inhibited by either staurosporine or Ro 31-8220. Pretreatment of cells with PMA for 4-24 h resulted in marked attenuation of UTP-stimulated cyclic AMP potentiation. 7. Pretreatment with pertussis toxin (24 h, 100 ng ml-1) did not significantly affect UTP-induced cyclic AMP potentiation and IP formation, although it increased the cyclic AMP response to PGE1. 8. Analysis of J774 cells by Western blotting with antibodies specific for different protein kinase C (PKC) isoforms shows the presence of the beta I, beta II, delta, epsilon, eta, mu, lambda and zeta isoforms. Moreover, UTP significantly increased the level of PKC beta I, beta II, delta, epsilon, mu, lambda and zeta immunoreactivity in the membrane fraction and decreased the cytosolic reactivity of PKC beta II, delta, epsilon and zeta. 9. Immunoblot studies also indicate the presence of type II adenylyl cyclase. 10. These results indicate that PKC is required for the potentiation of adenylyl cyclase activity by macrophage pyrimidinoceptors, which exhibit a higher specificity for UTP and UDP than for ATP.

Inhibition of ecto-ATPase by the P2 purinoceptor agonists, ATPgammaS, alpha,beta-methylene-ATP, and AMP-PNP, in endothelial cells

Ecto-ATPase is a plasma membrane-bound enzyme that sequentially dephosphorylates extracellular nucleotides such as ATP. This breakdown of ATP and other nucleotides makes it difficult to characterize and classify P2 purinoceptors. We have previously shown that the P2 purinergic antagonists, PPADS, suramin and reactive blue, act as ecto-ATPase inhibitors in various cell lines. Here, we show that the P2 purinergic agonists, ATPgammaS, alpha,beta-methylene ATP (alpha,beta-MeATP) and AMP-PNP, inhibit the ecto-ATPase of bovine pulmonary artery endothelial cells (CPAE), with pIC50 values of 5.2, 4.5 and 4.0, respectively. In CPAE, FPL67156, a selective ecto-ATPase inhibitor, also inhibits ecto-ATPase activity, with a pIC50 value of 4.0. In addition, alpha,beta-MeATP (3-100 microM), which itself does not induce phosphoinositide (PI) turnover, left-shifted the agonist-concentration effect (E/[A]) curves for ATP, 2MeS-ATP and UTP by approximate 100-300 fold, while those for ATPgammaS and AMP-PNP were only shifted approximately 2-3 fold. Moreover, in the presence of alpha,beta-MeATP, not only was the potentiation effect of PPADS on the UTP response lost, but a slight inhibition of the UTP response by PPADS was also seen. Thus, we conclude that the action of ATPgammaS, alpha,beta-MeATP and AMP-PNP as ecto-ATPase inhibitors account for their high agonist potency, and also provide information for the development of ecto-ATPase inhibitors of high selectivity and potency.

Inhibition of ecto-ATPase by PPADS, suramin and reactive blue in endothelial cells, C6 glioma cells and RAW 264.7 macrophages

1. Previous studies have shown that bovine pulmonary artery endothelium (CPAE) has P2Y and P2U purinoceptors, rat C6 glioma cells have P2U purinoceptors and mouse RAW 264.7 cells have pyrimidinoceptors, all of which are coupled to phosphoinositide-specific phospholipase C (PI-PLC). The dual actions of PPADS, suramin and reactive blue as antagonists of receptor subtypes and ecto-ATPase inhibitors were studied in these three cell types. 2. In CPAE, suramin, at 3-100 microM, competitively inhibited the PI responses induced by 2MeSATP and UTP, with pA2 values of 5.5 +/- 0.3 and 4.4 +/- 0.4, respectively. Reactive blue, at 1-3 microM, produced shifts to the right of the 2MeSATP and UTP curves, but no further right shift at 10 microM. PPADS, at 10 microM, caused a 3 fold right shift of the 2MeSATP curve, but no further shift at concentrations up to 100 microM. In contrast, a dose-dependent shift to the left of the UTP curve and a weak inhibition of the ATP response were seen with PPADS. 3. In RAW 264.7 cells, suramin and reactive blue, but not PPADS, competitively inhibited the UTP response, with pA2 values of 4.8 +/- 0.5 and 5.8 +/- 0.7, respectively. 4. In C6 glioma cells, although suramin and reactive blue inhibited the ATP response, a potentiation effect on ATP and UTP responses was seen with PPADS. 5. The ecto-ATPase inhibitory activity of these three receptor antagonists were determined. All three inhibited ecto-ATPase present in CPAE, C6 and RAW 264.7 cells, with IC50 values of 4, 4.8 and 4.7 for PPADS, 4, 4.4 and > > 4 for suramin, and 4.5, 4.7 and 4.7 for reactive blue. 6. This study indicates that PPADS, suramin and reactive blue ar ecto-ATPase inhibitors. This property, combined with their antagonistic selectivity for receptor subtypes, can result in inhibition of, potentiation of, or lack of effect on agonist-mediated PI responses. Reactive blue is a more potent antagonist than suramin on P2Y, P2U and pyrimidinoceptors, and PPADS is a weak antagonist for P2Y receptors.

Characterization of signaling pathways of P2Y and P2U purinoceptors in bovine pulmonary artery endothelial cells

The actions of ATP on the endothelium are mediated by P2 purinoceptors. We have shown that P2Y and P2U purinoceptors coexist in bovine pulmonary artery endothelial cells (CPAE), where they induce phosphoinositide (PI) turnover and Ca2+ mobilization. The relative order of potency (based on the threshold concentration) of nucleotide analogues (1-100 microM) in stimulating the accumulation of inositol phosphate (IP) was 2-methylthio-ATP (2MeSATP) = 2-methylthio-ADP (2MeSADP) > or = 2ClATP > UTP = ATP = ADP. alpha, beta-methylene ATP, beta, gamma-methylene ATP, UDP, adenosine-5'-tetraphospho-5'-adenosine, and adenosine-5'-pentaphospho-5'-adenosine had no effect at concentrations as high as 100 microM. At maximal concentrations, the IP responses to 2MeSATP and UTP were additive, whereas those to ATP and either 2MeSATP or UTP were not. Moreover, the maximal response to 2MeSADP was additive to that to UTP but not to that of 2MeSATP. Pretreatment with pertussis toxin slightly inhibited 2MeSATP- and UTP-stimulated IP generation by 15%. Under Ca(2+)-free conditions, UTP-induced IP formation was inhibited more markedly than that induced by 2MeSATP. Short-term treatment of the cells with phorbol 12-myristate-13-acetate (PMA) resulted in a dose-dependent inhibition of 2MeSATP-induced IP formation greater and more sensitive than that induced by UTP; similar results were obtained for the sensitivity of inhibition by suramin and reactive blue. Stimulation of the cells with either 2MeSATP or UTP induced a rapid increase in intracellular Ca2+ level, followed by a slow decrease to basal levels, followed by Ca2+ level oscillation. In the absence of extracellular Ca2+, [Ca2+]i responses were quantitatively less and did not show the slow phase and oscillation. Together these results suggest that both P2Y and P2U purinoceptors are expressed in bovine pulmonary artery endothelial cells and are coupled to phospholipase C (PLC) activation and Ca2+ mobilization through pertussis toxininsensitive G proteins.

Double-stranded cyclic oligonucleotides with non-nucleotide bridges

A series of double-stranded, cyclic oligodeoxynucleotides with non-nucleotide bridges have been synthesized, and their physicochemical properties and susceptibility to enzymes have been investigated. These bridged duplexes are of potential interest for their binding properties to transcription factors and other DNA-binding proteins. Triethylene glycol has been employed as the bridge to alter the lipophilicity of the duplex and avoid the potential for enzymatic cleavage. The synthetic route involved the synthesis of a 3'-phosphorylated, nicked double-stranded precursor with the final internucleotide bond being formed chemically using a water soluble carbodiimide. These bridged duplexes have high thermal dissociation temperatures, and the Tm for a triethylene-bridged 20 base pair duplex was higher than that for the corresponding pentathymidylate-bridged duplex. EcoR I endonuclease cleaved a ligated, bridged duplex at a slower rate than the corresponding unmodified duplex, whereas the unligated, bridged duplex was cleaved more rapidly. Sufficient amounts of the bridged octamer and dodecamer were prepared for proton NMR spectroscopic studies, and 2D COSY and NOESY spectra were obtained. The results indicate that the ligated duplex has a B-form conformation.