A distinct tumor microenvironment makes anaplastic thyroid cancer more lethal but immunotherapy sensitive than papillary thyroid cancer

Both anaplastic thyroid cancer (ATC) and papillary thyroid cancer (PTC) originate from thyroid follicular epithelial cells, but ATC has a significantly worse prognosis and shows resistance to conventional therapies. However, clinical trials found that immunotherapy works better in ATC than late-stage PTC. Here, we used single-cell RNA sequencing (scRNA-Seq) to generate a single-cell atlas of thyroid cancer. Differences in ATC and PTC tumor microenvironment components (including malignant cells, stromal cells, and immune cells) leading to the polarized prognoses were identified. Intriguingly, we found that CXCL13+ T lymphocytes were enriched in ATC samples and might promote the development of early tertiary lymphoid structure (TLS). Last, murine experiments and scRNA-Seq analysis of a treated patient's tumor demonstrated that famitinib plus anti-PD-1 antibody could advance TLS in thyroid cancer. We displayed the cellular landscape of ATC and PTC, finding that CXCL13+ T cells and early TLS might make ATC more sensitive to immunotherapy.

Fed-batch anaerobic digestion of raw and pretreated hazelnut skin over long-term operation

This study provided important insights on the anaerobic digestion (AD) of hazelnut skin (HS) by operating a fed-batch AD reactor over 240 days and focusing on several factors impacting the process in the long term. An efficient reactor configuration was proposed to increase the substrate load while reducing the solid retention time during the fed-batch AD of HS. Raw HS produced maximally 19.29 mL CH₄/g VS_add/d. Polyphenols accumulated in the reactor and the use of NaOH to adjust the pH likely inhibited AD. Maceration and methanol-organosolv pretreatments were, thus, used to remove polyphenols from HS (i.e. 82 and 97%, respectively) and improve HS biodegradation. Additionally, organosolv pretreatment removed 9% of the lignin. The organosolv-pretreated HS showed an increment in methane potential of 21%, while macerated HS produced less methane than the raw substrate, probably due to the loss of non-structural sugars during maceration.

Textbook outcome following oesophagectomy for cancer: international cohort study

Background

Textbook outcome has been proposed as a tool for the assessment of oncological surgical care. However, an international assessment in patients undergoing oesophagectomy for oesophageal cancer has not been reported. This study aimed to assess textbook outcome in an international setting.

Methods

Patients undergoing curative resection for oesophageal cancer were identified from the international Oesophagogastric Anastomosis Audit (OGAA) from April 2018 to December 2018. Textbook outcome was defined as the percentage of patients who underwent a complete tumour resection with at least 15 lymph nodes in the resected specimen and an uneventful postoperative course, without hospital readmission. A multivariable binary logistic regression model was used to identify factors independently associated with textbook outcome, and results are presented as odds ratio (OR) and 95 per cent confidence intervals (95 per cent c.i.).

Results

Of 2159 patients with oesophageal cancer, 39.7 per cent achieved a textbook outcome. The outcome parameter ‘no major postoperative complication’ had the greatest negative impact on a textbook outcome for patients with oesophageal cancer, compared to other textbook outcome parameters. Multivariable analysis identified male gender and increasing Charlson comorbidity index with a significantly lower likelihood of textbook outcome. Presence of 24-hour on-call rota for oesophageal surgeons (OR 2.05, 95 per cent c.i. 1.30 to 3.22; P = 0.002) and radiology (OR 1.54, 95 per cent c.i. 1.05 to 2.24; P = 0.027), total minimally invasive oesophagectomies (OR 1.63, 95 per cent c.i. 1.27 to 2.08; P < 0.001), and chest anastomosis above azygous (OR 2.17, 95 per cent c.i. 1.58 to 2.98; P < 0.001) were independently associated with a significantly increased likelihood of textbook outcome.

Conclusion

Textbook outcome is achieved in less than 40 per cent of patients having oesophagectomy for cancer. Improvements in centralization, hospital resources, access to minimal access surgery, and adoption of newer techniques for improving lymph node yield could improve textbook outcome.

Textbook outcome following oesophagectomy for cancer: international cohort study

BACKGROUND

Textbook outcome has been proposed as a tool for the assessment of oncological surgical care. However, an international assessment in patients undergoing oesophagectomy for oesophageal cancer has not been reported. This study aimed to assess textbook outcome in an international setting.

METHODS

Patients undergoing curative resection for oesophageal cancer were identified from the international Oesophagogastric Anastomosis Audit (OGAA) from April 2018 to December 2018. Textbook outcome was defined as the percentage of patients who underwent a complete tumour resection with at least 15 lymph nodes in the resected specimen and an uneventful postoperative course, without hospital readmission. A multivariable binary logistic regression model was used to identify factors independently associated with textbook outcome, and results are presented as odds ratio (OR) and 95 per cent confidence intervals (95 per cent c.i.).

RESULTS

Of 2159 patients with oesophageal cancer, 39.7 per cent achieved a textbook outcome. The outcome parameter 'no major postoperative complication' had the greatest negative impact on a textbook outcome for patients with oesophageal cancer, compared to other textbook outcome parameters. Multivariable analysis identified male gender and increasing Charlson comorbidity index with a significantly lower likelihood of textbook outcome. Presence of 24-hour on-call rota for oesophageal surgeons (OR 2.05, 95 per cent c.i. 1.30 to 3.22; P = 0.002) and radiology (OR 1.54, 95 per cent c.i. 1.05 to 2.24; P = 0.027), total minimally invasive oesophagectomies (OR 1.63, 95 per cent c.i. 1.27 to 2.08; P < 0.001), and chest anastomosis above azygous (OR 2.17, 95 per cent c.i. 1.58 to 2.98; P < 0.001) were independently associated with a significantly increased likelihood of textbook outcome.

CONCLUSION

Textbook outcome is achieved in less than 40 per cent of patients having oesophagectomy for cancer. Improvements in centralization, hospital resources, access to minimal access surgery, and adoption of newer techniques for improving lymph node yield could improve textbook outcome.

Different clinicopathologic features predispose to different patterns of distant metastasis with heterogeneous short-term prognosis in patients with differentiated thyroid cancer

BACKGROUND

Limited studies have focused on the associated clinicopathologic features and short-term prognostic impacts of metastatic patterns at initial diagnosis in differentiated thyroid cancer (DTC).

METHODS

Overall, 530 individuals with distant DTC diagnosed between 2010 and 2014 were identified from Surveillance, Epidemiology, and End Results (SEER) database. Multinomial logistic regression model was used to assess the clinicopathologic factors influencing the pattern of distant metastasis. Kaplan-Meier method and multivariable Cox regression were used to estimate the short-term effects of metastatic patterns on overall (OS) and thyroid cancer-specific survival (TCSS).

RESULTS

Fifty, 111, 263, 59 and 47 patients presented with distant lymph node (LN)-only, bone-only, lung-only, bone plus lung, and liver and/or brain metastases (Mets), respectively. Regional lymph node metastasis (LNM) and follicular histotype were the only confirmed risk factors for distant LN-only Mets and bone-only Mets, respectively. Larger tumour size, extrathyroidal extension (ETE) and papillary histotype were associated with lung-only Mets. Synchronous bone and lung Mets were more likely to occur in older patients. In addition, patients with distant LN-only Mets had hardly any negative effect on OS and TCSS, whereas those with synchronous bone and lung or liver/brain Mets predicted unfavourable short-term outcomes, regardless of whether they received total thyroidectomy and radioisotopes.

CONCLUSIONS

Different clinicopathologic factors predispose to different patterns of metastases with profound short-term survival differences among DTC patients. Our findings may help to determine effective pretreatment screening for aggressive metastatic patterns at initial diagnosis, and thus to provide additional treatment or access of clinical trials for these patients.

A novel method to reconstruct right recurrent laryngeal nerve by transforming into nonrecurrent laryngeal nerve: The end-to-free vagal laryngeal branch end anastomosis

The objective of this study is to demonstrate a novel method for the reconstruction of right recurrent laryngeal nerve (RLN) by transforming into nonrecurrent RLN: the end-to-free vagal laryngeal branch end anastomosis. Here we report a case of locally advanced thyroid carcinoma. The patient underwent radical thyroid surgery with inevitably partial RLN resection and immediate right RLN reconstruction at our institution. With the guidance of intraoperative neuromonitoring (IOMN), we completed a novel end-to-free vagal laryngeal branch end anastomosis. The whole procedure was deliberately monitored by IOMN. Surgeons can procure adequate free nerve for tension-free anastomosis by transforming the right RLN into nonrecurrent nerve. Follow-up laryngoscope showed improved adductory movement of the right arytenoid. The end-to-free vagal end anastomosis is an effective way to reconstruct segmental nerve resection of right RLN. Its long-term postoperative result needs to be further warranted.

Postoperative outcomes in oesophagectomy with trainee involvement

BACKGROUND

The complexity of oesophageal surgery and the significant risk of morbidity necessitates that oesophagectomy is predominantly performed by a consultant surgeon, or a senior trainee under their supervision. The aim of this study was to determine the impact of trainee involvement in oesophagectomy on postoperative outcomes in an international multicentre setting.

METHODS

Data from the multicentre Oesophago-Gastric Anastomosis Study Group (OGAA) cohort study were analysed, which comprised prospectively collected data from patients undergoing oesophagectomy for oesophageal cancer between April 2018 and December 2018. Procedures were grouped by the level of trainee involvement, and univariable and multivariable analyses were performed to compare patient outcomes across groups.

RESULTS

Of 2232 oesophagectomies from 137 centres in 41 countries, trainees were involved in 29.1 per cent of them (n = 650), performing only the abdominal phase in 230, only the chest and/or neck phases in 130, and all phases in 315 procedures. For procedures with a chest anastomosis, those with trainee involvement had similar 90-day mortality, complication and reoperation rates to consultant-performed oesophagectomies (P = 0.451, P = 0.318, and P = 0.382, respectively), while anastomotic leak rates were significantly lower in the trainee groups (P = 0.030). Procedures with a neck anastomosis had equivalent complication, anastomotic leak, and reoperation rates (P = 0.150, P = 0.430, and P = 0.632, respectively) in trainee-involved versus consultant-performed oesophagectomies, with significantly lower 90-day mortality in the trainee groups (P = 0.005).

CONCLUSION

Trainee involvement was not found to be associated with significantly inferior postoperative outcomes for selected patients undergoing oesophagectomy. The results support continued supervised trainee involvement in oesophageal cancer surgery.

Next-Generation Sequencing Enhances the Diagnosis Efficiency in Thyroid Nodules

BACKGROUND

Though fine-needle aspiration (FNA) improved the diagnostic methods of thyroid nodules, there are still parts of nodules that cannot be determined according to cytology. In the Bethesda system for reporting thyroid cytopathology, there are two uncertain cytology results. Thanks to the development of next-generation sequencing technology, it is possible to gain the genetic background of pathological tissue efficiently. Therefore, a combination of the cytology and genetic background may enhance the accuracy of diagnosis in thyroid nodules.

METHODS

DNA from 73 FNA samples of thyroid nodules belonging to different cytology types was extracted and exome sequencing was performed by the ThyroLead panel. Test for BRAF mutation was also performed by ARMS-qPCR. Information including age, sex, preoperative cytology, BRAF mutation status tested by ARMS-qPCR, and surgical pathology was collected in electronic medical record system.

RESULTS

A total of 71 single nucleotide variants, three fusion gene, and two microsatellite instability-high status were detected in 73 FNA samples. BRAF V600E mutation is the most common mutation in these malignant thyroid nodules. After combining the cytology and genetic background detected by next-generation sequencing, the diagnosis sensitivity was increased from 0.582 (95% CI: 0.441-0.711) to 0.855 (95% CI: 0.728-0.930) (P < 0.001) in our group, while the specificity, 1,000 (95% CI: 0.732-1.000) compared to 0.857 (95% CI: 0.562-0.975) (P = 0.25), did not get affected.

CONCLUSIONS

Next-generation sequencing in thyroid nodules can enhance the preoperative diagnosis sensitivity by fine-needle aspiration alone. It can also provide genetic background for direction of medication. It is possible for clinicians to combine cytology with genetic alterations for a more precise diagnosis strategy of thyroid nodules.

Comparison of short-term outcomes from the International Oesophago-Gastric Anastomosis Audit (OGAA), the Esophagectomy Complications Consensus Group (ECCG), and the Dutch Upper Gastrointestinal Cancer Audit (DUCA)

BACKGROUND

The Esophagectomy Complications Consensus Group (ECCG) and the Dutch Upper Gastrointestinal Cancer Audit (DUCA) have set standards in reporting outcomes after oesophagectomy. Reporting outcomes from selected high-volume centres or centralized national cancer programmes may not, however, be reflective of the true global prevalence of complications. This study aimed to compare complication rates after oesophagectomy from these existing sources with those of an unselected international cohort from the Oesophago-Gastric Anastomosis Audit (OGAA).

METHODS

The OGAA was a prospective multicentre cohort study coordinated by the West Midlands Research Collaborative, and included patients undergoing oesophagectomy for oesophageal cancer between April and December 2018, with 90 days of follow-up.

RESULTS

The OGAA study included 2247 oesophagectomies across 137 hospitals in 41 countries. Comparisons with the ECCG and DUCA found differences in baseline demographics between the three cohorts, including age, ASA grade, and rates of chronic pulmonary disease. The OGAA had the lowest rates of neoadjuvant treatment (OGAA 75.1 per cent, ECCG 78.9 per cent, DUCA 93.5 per cent; P < 0.001). DUCA exhibited the highest rates of minimally invasive surgery (OGAA 57.2 per cent, ECCG 47.9 per cent, DUCA 85.8 per cent; P < 0.001). Overall complication rates were similar in the three cohorts (OGAA 63.6 per cent, ECCG 59.0 per cent, DUCA 62.2 per cent), with no statistically significant difference in Clavien-Dindo grades (P = 0.752). However, a significant difference in 30-day mortality was observed, with DUCA reporting the lowest rate (OGAA 3.2 per cent, ECCG 2.4 per cent, DUCA 1.7 per cent; P = 0.013).

CONCLUSION

Despite differences in rates of co-morbidities, oncological treatment strategies, and access to minimal-access surgery, overall complication rates were similar in the three cohorts.

Arms-qPCR Improves Detection Sensitivity of Earlier Diagnosis of Papillary Thyroid Cancers With Worse Prognosis Determined by Coexisting BRAF V600E and Tert Promoter Mutations

OBJECTIVE

The coexistence of BRAF V600E and the telomerase reverse transcriptase (TERT) promoter mutation C228T/C250T is extensively associated with thyroid cancer prognosis. Our study aimed to establish a sensitive method for mutation detection and explore the correlation in detail.

METHODS

The BRAF and TERT promoter mutation status of 250 papillary thyroid cancers was determined using amplification-refractory mutation system quantitative polymerase chain reaction (ARMS-qPCR) and Sanger sequencing to compare the sensitivity of the 2 methods. Associations between the mutation status and clinicopathological features were then analyzed.

RESULTS

ARMS-qPCR was more sensitive than Sanger sequencing (BRAF V600E: 75.2% [188 of 250] vs 52.4% [131 of 250], P < .001; TERT promoter C228T/C250T mutation: 12.0% [30 of 250] vs 3.6% [9 of 250], P = .001; comutation: 9.6% [24 of 250] vs 3.2% [8 of 250], P = .005). Both ARMS-qPCR and Sanger sequencing indicated that patients with coexisting BRAF V600E and TERT promoter mutations had an older diagnosis age, higher recurrence rate, and were associated with a more advanced TNM stage and higher metastasis, age, completeness of resection, invasion, and size score. Moreover, ARMS-qPCR helped identify an earlier group stage, which was younger and had smaller tumors and a lower recurrence rate, compared with the group with coexisting BRAF V600E and TERT promoter mutations identified by Sanger sequencing. The newly identified group had a lower metastasis, age, completeness of resection, invasion, and size score and TNM stage.

CONCLUSION

Patients with coexisting BRAF V600E and TERT promoter mutations had a worse prognosis. ARMS-qPCR, the more sensitive method, can be used to identify patients who have a potentially worse prognosis earlier.

Immune Co-inhibitory Receptors PD-1, CTLA-4, TIM-3, LAG-3, and TIGIT in Medullary Thyroid Cancers: A Large Cohort Study

CONTEXT

Programmed cell death protein-1 (PD-1), cytotoxic T-lymphocyte antigen 4 (CTLA-4), T-cell immunoglobulin and mucin-domain containing-3 (TIM-3), lymphocyte activation gene-3 (LAG-3), and T-cell immunoglobulin and ITIM domain (TIGIT) are considered major immune co-inhibitory receptors (CIRs) and the most promising immunotherapeutic targets in cancer treatment, but they are largely unexplored in medullary thyroid carcinoma (MTC).

OBJECTIVE

We aimed to provide the first evidence regarding the expression profiles and clinical significance of CIRs in a large cohort of MTC patients.

DESIGN AND PATIENTS

In total, 200 MTC patients who received initial surgery in our hospital were included. Immunohistochemistry was performed to evaluate CIR expressions in tissue microarrays (TMAs). Combined with the results of our previous programmed cell death ligand-1 (PD-L1) study, clinicopathologic and prognostic correlations of these proteins were retrospectively analyzed.

RESULTS

TIM-3, PD-1, CTLA-4, LAG-3, and TIGIT positivity was detected in 96 (48.0%), 27 (13.5%), 25 (12.5%), 6 (3.0%), and 6 (3.0%) patients, respectively, in whom TIM-3, PD-1, and CTLA-4 expressions were positively correlated. Log-rank tests and multivariate Cox analyses both indicated that TIM-3, CTLA-4 expression, and PD-1/PD-L1 coexpression were associated with worse structural recurrence-free survival. In addition, among 20 patients who developed advanced disease during follow-up, 12 (60%) showed TIM-3 positivity, among whom 6 cases also had concurrent moderate to strong PD-1, PD-L1, or CTLA-4 expression.

CONCLUSIONS

Using the currently largest TMA cohort of this rare cancer, we delineated the CIR expression profiles in MTC, and identified TIM-3, CTLA-4 expression, and PD-1/PD-L1 coexpression as promising biomarkers for tumor recurrence. Furthermore, a subset of advanced MTCs are probably immunogenic, for which single or combined immunotherapy including TIM-3, PD-1, PD-L1, or CTLA-4 blockade may be potential therapeutic approaches in the future.

Mitotically associated long non-coding RNA is a tumor promoter in anaplastic thyroid cancer

Background

Patients with anaplastic thyroid cancer (ATC), which is among the deadliest of all cancers, often have a poor response to traditional therapies. Currently, the role of long non-coding RNAs (lncRNAs) in ATC carcinogenesis is unclear. In this study, we analyzed the lncRNA expression profile of ATC with the aim of identifying potential molecular targets for treatment of the disease.

Methods

Whole transcriptome sequencing of three ATC and two normal thyroid (NT) samples was performed, and the lncRNA expression profile of ATC was analyzed. Original data as well as datasets deposited in the Gene Expression Omnibus (GEO) and The Cancer Genome Atlas (TCGA) were used for clinical validation. Cell proliferation, Transwell, and apoptosis assays were performed using ATC cell lines. Gene Ontology (GO) and gene set enrichment analyses (GSEA) were performed to determine the dysregulated pathways.

Results

Whole transcriptome sequencing revealed 182 lncRNAs to be differentially expressed in ATC. One of the lncRNAs, mitotically associated long non-coding RNA (MANCR; LINC00704), was significantly overexpressed in ATC cell lines and patient samples compared with NT and papillary thyroid cancer (PTC). MANCR depletion in ATC cells significantly inhibited cancer cell proliferation and invasion, and induced apoptosis. By further analyzing the transcriptome data, we identified 451 genes co-expressed with MANCR. GO and GSEA showed that the top dysregulated pathways were related to mitosis and cell cycle.

Conclusions

MANCR is a tumor promoter in ATC, and its role in carcinogenesis is possibly associated with cell cycle regulation. Because MANCR expression is minimal in most normal tissues, it may serve as a potential target in the future treatment of ATC.

Perioperative intravenous contrast administration and the incidence of acute kidney injury after major gastrointestinal surgery: prospective, multicentre cohort study

BACKGROUND

This study aimed to determine the impact of preoperative exposure to intravenous contrast for CT and the risk of developing postoperative acute kidney injury (AKI) in patients undergoing major gastrointestinal surgery.

METHODS

This prospective, multicentre cohort study included adults undergoing gastrointestinal resection, stoma reversal or liver resection. Both elective and emergency procedures were included. Preoperative exposure to intravenous contrast was defined as exposure to contrast administered for the purposes of CT up to 7 days before surgery. The primary endpoint was the rate of AKI within 7 days. Propensity score-matched models were adjusted for patient, disease and operative variables. In a sensitivity analysis, a propensity score-matched model explored the association between preoperative exposure to contrast and AKI in the first 48 h after surgery.

RESULTS

A total of 5378 patients were included across 173 centres. Overall, 1249 patients (23·2 per cent) received intravenous contrast. The overall rate of AKI within 7 days of surgery was 13·4 per cent (718 of 5378). In the propensity score-matched model, preoperative exposure to contrast was not associated with AKI within 7 days (odds ratio (OR) 0·95, 95 per cent c.i. 0·73 to 1·21; P = 0·669). The sensitivity analysis showed no association between preoperative contrast administration and AKI within 48 h after operation (OR 1·09, 0·84 to 1·41; P = 0·498).

CONCLUSION

There was no association between preoperative intravenous contrast administered for CT up to 7 days before surgery and postoperative AKI. Risk of contrast-induced nephropathy should not be used as a reason to avoid contrast-enhanced CT.

Association Between Programmed Death-Ligand 1 Expression and Clinicopathological Characteristics, Structural Recurrence, and Biochemical Recurrence/Persistent Disease in Medullary Thyroid Carcinoma

Background: Expression of the programmed death-ligand 1 (PD-L1) in medullary thyroid carcinoma (MTC) has been rarely reported. In this study, we evaluated PD-L1 positivity in MTC and analyzed its correlation with clinicopathological characteristics, structural recurrence (SR), and biochemical recurrence/persistent disease (BcR/BcPD). We also evaluated the prevalence of PD-L1 expression in patients developing distant or unresectable locoregional recurrence. Methods: In total, 201 consecutive MTC patients who underwent initial surgery in our institution from January 2006 to December 2015 were included. PD-L1 expression was evaluated by immunohistochemical staining and was considered positive in case of a combined positive score ≥1. The association of PD-L1 positivity with clinicopathological characteristics, structural recurrence-free survival (SRFS), and BcR/BcPD was retrospectively investigated. Results: The median follow-up length of the entire cohort was 73 months. We observed positive PD-L1 staining in 29 (14.4%) patients who were more likely to have a larger tumor size (p = 0.002), lymph node metastases (p = 0.036), and advanced TNM staging (p = 0.019). The five-year SRFS of the PD-L1-negative and PD-L1-positive groups was 85.4% and 57.9% (p = 0.001). Multivariate Cox analysis showed that PD-L1 positivity was independently associated with SR (hazard ratio = 2.19 [95% confidence interval (CI) 1.01-4.77], p = 0.047). Furthermore, multivariate logistic analysis showed that PD-L1 positivity was significantly associated with BcR/BcPD (odds ratio = 3.16 [CI 1.16-8.66], p = 0.025). During the study period, 20 patients developed distant or unresectable locoregional recurrence, among whom 8 (40%) were PD-L1 positive, which was much higher than in the entire MTC population. Conclusions: Using a large cohort of MTC patients, we demonstrate that PD-L1 positivity is associated with aggressive clinicopathological features and is independently predictive of SR and BcR/BcPD. Furthermore, a higher rate of PD-L1 expression in patients with incurable recurrence has been observed. Therefore, immune checkpoint inhibitors targeting the programmed cell death-1 (PD-1)/PD-L1 pathway may be a potential therapeutic strategy to treat advanced MTC.

Treating Clinically Node-Negative Insular Thyroid Carcinoma without Prophylactic Central Compartment Neck Dissection Is Associated with Decreased Survival Regardless of T Staging and Administration of Radioactive Iodine Therapy: The First Evidence

For the rare but aggressive insular thyroid carcinoma (ITC), there's no clear evidence to determine whether prophylactic central compartment neck dissection (CCND) is necessary for cN0 disease. This study provides the first evidence that treating cN0 ITC without prophylactic CCND is associated with decreased survival regardless of T staging and administration of RAI therapy. Background. Regarding the rare but aggressive insular thyroid carcinoma (ITC), the value of prophylactic central compartment neck dissection (CCND) for clinically node-negative (cN0) disease is unclear. We aimed to provide the first evidence. Methods. N0 and pN1a ITC patients were identified from the Surveillance, Epidemiology, and End Results database. These patients were divided into thyroid-surgery + CCND group (pN0/pN1a patients confirmed by CCND) and thyroid-surgery group (cN0 patients without CCND). Differences in overall survival (OS) and disease-specific survival (DSS) between the two groups were evaluated. Subgroup analyses were also conducted. Results. Of the overall 112 patients, 44 (39.3%) received CCND. On multivariate analyses, the lobectomy ± isthmusectomy/total-thyroidectomy (Lob/TT) group demonstrated poorer OS and DSS than the Lob/TT + CCND group (P < 0.05). When we separately analyzed patients treated by TT, multivariate analyses showed the TT group still revealed compromised OS and DSS than the TT + CCND group (P < 0.05). Furthermore, absence of CCND independently predicted decreased OS no matter whether radioactive iodine (RAI) was administered. Similar results were obtained for T3/T4 patients. Moreover, for T1/T2 patients receiving CCND, 0/12 died during the study period, while for T1/T2 patients without CCND, 8/23 (34.8%) died, 5/23 (21.7%) due to ITC. Conclusion. Regardless of T staging and RAI treatment, cN0-ITC patients without CCND had decreased survival compared with pN0/pN1a patients receiving CCND. Therefore, if a cN0 patient is diagnosed with ITC, prophylactic CCND may be considered as a secondary procedure (postoperatively diagnosed) or a primary procedure (preoperatively/intraoperatively diagnosed). Prospective studies are expected to validate the conclusion.

No association of DNM3 with age of onset in Asian Parkinson's disease

BACKGROUND AND PURPOSE

Genetic variability in DNM3 has been shown to modify age of onset of Parkinson's disease (PD) among LRRK2 Gly2019Ser carriers in North African Arab-Berber populations. In Asian populations, the Gly2019Ser mutation is rare or absent but two other LRRK2 variants, Gly2385Arg and Arg1628PPro, increase PD risk. We aimed to determine whether the DNM3 locus was associated with age of PD onset in both carriers and non-carriers of LRRK2 risk variants in Asians.

METHODS

We analyzed the association of DNM3 rs2421947 genotypes with age of PD onset in 3645 Chinese samples, of which 369 carried at least one of two Asian LRRK2 risk variants.

RESULTS

DNM3 rs2421947 genotypes were not associated with age of PD onset in Chinese samples. We observed no heterogeneity in the effect of rs2421947 between the Asian LRRK2 risk variant carriers and non-carriers.

CONCLUSIONS

DNM3 rs2421947 was not associated with age of PD onset in LRRK2 risk variant carriers and non-carriers in Chinese samples. Further studies in other Asian populations will be of interest.

[Antagonism of lovastatin on oxidative stress and apoptosis in primary rat hippocampal neurons induced by β-amyloid peptide]

Objective: To investigate the effect of lovastatin on oxidative stress and apoptosis in neurons induced by β-amyloid peptide (Aβ). Methods: Primary culture of rat hippocampal neuron was treated with Aβ oligomers alone or combined with lovastatin. The levels of OH(-), H(2)O(2), O(2)·(-), malondialdehyde, superoxide dismutase (SOD) and glutathione peroxidase (GSH-PX) activities were measured by biochemical methods and protein expression of caspase-3 and bcl-2 was detected by Western blot. Results: As compared with the control group, treatment of 0.5 μmol/L Aβ oligomers for 48 h led to significant increase of OH(-), H(2)O(2), O(2)·(-) and malondialdehyde content, inhibition of SOD and GSH-PX activities, enhanced caspase-3 expression and decreased bcl-2 expression. Interestingly, these neurotoxic modifications on the levels of OH(-), H(2)O(2), O(2)·(-) and malondialdehyde content, SOD and GSH-PX activities, and the protein expression of cleaved caspase-3 and bcl-2 were significantly attenuated when the cells were pretreated with 0.1 μmol/L lovastatin for 24 h before exposure of Aβ oligomers. Conclusion: Lovastatin may play an important role in antagonizing the neurotoxicity of Aβ through a mechanism likely related to the inhibition of oxidative stress.

Analysis of GWAS-linked loci in Parkinson disease reaffirms PARK16 as a susceptibility locus

OBJECTIVE

A genome-wide association study (GWAS) in the Japanese population identified 2 new Parkinson disease (PD) susceptibility loci on 1q32 (PARK16) (OMIM 613164) and BST1. We analyzed single nucleotide polymorphism (SNPs) located at the GWAS-linked loci (PARK16, PARK8, PARK1, and BST1) in a Chinese population and also conducted a meta-analysis in Asians by pooling 2 independent replication studies from Japan.

METHODS

We conducted an analysis of 13 SNPs associated with PD GWAS-linked loci in 2 case-control cohorts comprised of 1,349 ethnic Chinese subjects.

RESULTS

PARK16, PARK8, and PARK1 loci but not BST1 were found to be associated with PD. PARK16 SNPs were associated with a decreased risk while PARK1 and PARK8 SNPs were associated with an increased risk of PD. A pooled analysis of our Chinese cohorts and 2 Japanese replication cohorts involving 1,366 subjects with PD and 16,669 controls revealed robust association with these 3 loci and also BST1. There was a trend toward a stronger protective effect of SNPs at the PARK16 locus in sporadic PD compared to familial cases and in older compared to younger subjects.

CONCLUSIONS

Our study reaffirms the role of GWAS-linked loci in PD in Asian subjects and the strength of association is similar between Chinese and Japanese subjects. Efforts to elucidate the associated gene within PARK16 locus are warranted.

Analysis of the UCHL1 genetic variant in Parkinson's disease among Chinese

The inverse association of the functional ubiquitin carboxy-terminal hydrolase L1 (UCHL1) S18Y variant with Parkinson's disease (PD) among Caucasian populations has been debated. We conducted a large-scale analysis to investigate the age-of-onset effect of the UCHL1 variant in PD among ethnic Chinese. Individual data sets from 5 centers comprising a total of 4088 study subjects were analyzed. In the univariate analysis, only data from 1 center showed a trend towards a protective effect among young subjects. However, in the combined analysis, no significant association between the UCHL1 variant and PD was detected (A allele frequency 0.531 vs. 0.528, p=0.87, OR 1.01, 95% CI 0.92-1.1). Among subjects less than 60 years old, the OR is 0.99 (95% CI 0.84-1.16, p=0.88). A multivariate logistic regression analysis showed that family history, UCHL1 variant and the interaction of UCHL1 variant and age at onset (p=0.816) were not significantly associated with PD.

Safe transition from open to laparoscopic fundoplication by an established consultant--the importance of repeated audit

BACKGROUND

Serious complications of laparoscopic fundoplication (LF) have been reported by surgeons new to LF. We investigated whether the reported benefits of LF could be realised by an established consultant, new to LF, without compromising safety, control of reflux or dysphagia rates obtained after open surgery.

PATIENTS AND METHODS

Outcome of 65 consecutive open fundoplications was audited. After training in LF, this audit was compared with an identical prospective audit of 65 patients undergoing LF.

RESULTS

No significant differences occurred between the two groups in relief of reflux. LF resulted in: (i) shorter postoperative stay (median 2 days versus 7 days, P < 0.001); (ii) earlier return to work (median 4 weeks versus 9 weeks, P < 0.001); (iii) shorter duration of postoperative dysphagia (median 4 weeks versus 9 weeks, P = 0.01); and (iv) less intra/postoperative complications (7.7% versus 32.3%, P < 0.001).

CONCLUSIONS

LF can be introduced safely by established consultants provided that adequacy of training is confirmed by repeated audit.

Dysfunctional Epstein-Barr virus (EBV)-specific CD8(+) T lymphocytes and increased EBV load in HIV-1 infected individuals progressing to AIDS-related non-Hodgkin lymphoma

Acquired immunodeficiency syndrome-related non-Hodgkin lymphomas (AIDS-NHL) are thought to arise because of loss of Epstein-Barr Virus (EBV)-specific cellular immunity. Here, an investigation was done to determine whether cellular immunity to EBV is lost because of physical loss or dysfunction of EBV-specific cytotoxic T cells. Data on EBV-specific cellular immunity were correlated with EBV load. For comparison, individuals who progressed to AIDS with opportunistic infections (AIDS-OI) and long-term asymptomatics (LTAs) were studied. The number of virus-specific T cells was detected using tetrameric HLA-EBV-peptide complexes; function of these EBV-specific T cells was determined using the interferon-gamma (IFN-gamma) Elispot assay. It was observed that EBV-specific CD8(+) T cells were present in normal numbers in human immunodeficiency virus (HIV)-infected individuals. However, their functional capacity was decreased compared with HIV(-) individuals. In AIDS-NHL patients, EBV-specific T cells were not physically lost in the course of HIV-1 infection but showed progressive loss of their capability to produce IFN-gamma in response to EBV peptides. This loss of function correlated with lower CD4(+) T-cell numbers and was accompanied by increasing EBV load. In HIV-1-infected LTA individuals, in whom CD4(+) T-cell numbers were maintained, and progressors to AIDS-OI, IFN-gamma-producing EBV-specific T cells were stable and EBV load remained stable or decreased in the course of HIV infection, suggestive of immune control. Our data indicate that functional loss of EBV-specific CD8(+) T cells with a concomitant increase in EBV load may play a role in the pathogenesis of AIDS-NHL.

The inferior vena caval conduit--a neglected technique in transplantation of the right cadaveric kidney?

A short right renal vein may reduce access or compromise optimal positioning during transplantation of the right cadaveric kidney. This difficulty could be overcome by using the inferior vena cava (IVC) as a venous conduit to lengthen the short right renal vein. This manoeuvre would also facilitate training by ensuring safe tension-free vascular anastomoses since the kidney can be lifted up a comfortable distance, thus improving exposure of the operative field. In a postal survey, only a third of UK renal transplant units utilised the IVC conduit. Despite 81.5% of units claiming that they harvest the IVC during organ retrieval, a 2-year retrospective audit revealed that only 4.3% of imported right kidneys had the IVC. The IVC remains a much under-utilised resource in the UK despite its potential benefit as a venous conduit in transplanting the right cadaveric kidney. We urge all retrieving surgeons to routinely harvest the IVC with right cadaveric kidneys during organ procurement.

A re-evaluation of the frequency of CD8+ T cells specific for EBV in healthy virus carriers

EBV is a gammaherpesvirus that can establish both nonproductive (latent) and productive (lytic) infections within the cells of its host. Although T cell responses to EBV latent proteins have been well characterized, little is known about the importance of responses to lytic proteins in long term virus carriers. Here we have compared the frequencies of CD8+ T cells specific for EBV latent and lytic Ags in healthy virus carriers, using three techniques: limiting dilution analysis, enzyme-linked immunospot assay, and FACS staining with tetrameric MHC-peptide complexes. T cells specific for EBV lytic protein epitopes were readily detectable in all donors and were usually more abundant than those specific for latent epitopes. We infer that direct T cell control of viral replicative lesions is maintained in long term carriers of EBV and is an important component of the immune response to this virus. Estimates of CD8+ T cell frequencies varied considerably according to methodology; values obtained from MHC-peptide tetramer staining were, on the average, 4.4-fold higher than those obtained from enzyme-linked immunospot assays, which were, in turn, on the average, 5.3-fold higher than those obtained from limiting dilution analysis. Tetramer staining showed that as many as 5.5% circulating CD8+ T cells in a virus carrier were specific for a single EBV lytic protein epitope. Such values are much greater than previously imagined and illustrate how antigenic challenge from a persistent herpesvirus can influence the composition of the host's CD8+ T cell pool.

The profile of hospitalised patients with Parkinson's disease

The objective of this study was to provide a profile of patients with Parkinson's disease (PD) who required admission to hospital. We reviewed retrospectively all patients with PD who were admitted to our hospital in 1995. In our study, there were 260 admissions involving 173 PD patients. The average age was 74.7 years. Of these patients, 93 were males and 80 were females. There were 150 Chinese, 12 Indians, 9 Malays, and 2 of other races. The average duration of hospitalisation was 11.7 days. The main reasons for admissions were: 1) chest infections (22%), 2) falls (13%), 3) control of PD symptoms (10%), 4) general medical problems (9%) and 5) urinary dysfunction (8%). Nine per cent were classified as Hoehn and Yahr stage 2, 31% as stage 3, 31% as stage 4 and 24% as stage 5. Twenty-one per cent of our patients were first diagnosed with PD during their hospitalisation. Upon discharge, 26% required transfer to either a community hospital or nursing home. The current in-patient load of PD patients is expected to rise with the ageing population. A significant number of people within the community may have undiagnosed PD. These patients suffer multiple medical problems and need a multi-disciplinary team approach to management. Greater resources will be required to support these patients in the community.

Paroxysmal kinesigenic choreoathetosis in Singapore and its relationship to epilepsy

OBJECTIVES

To study the clinical characteristics of paroxysmal kinesigenic choreoathetosis (PKC) in our local population and its relationship to epilepsy.

METHODS

We reviewed retrospectively 15 patients who were managed by neurologists in our department from 1982 to 1996. The literature was also reviewed to study the association between PKC and epilepsy.

RESULTS

In our study, all the cases were idiopathic. The male to female ratio was 14:1 with all major races represented. Sixty percent of our patients suffered dystonic posturing rather than chorea, during the attacks. Twenty-one percent had a family history of a similar disorder which appeared to be of autosomal dominant inheritance. The sporadic form (79%) predominated in Singapore. One had a history of febrile fits while two had a history of epilepsy. We reviewed the available literature and found five other patients with idiopathic PKC also suffering from epilepsy. Of the 83 patients reviewed, 8% had epilepsy. This further strengthens the relationship between the two conditions. All our patients responded well to phenytoin at doses between 100 and 400 mg/day.

CONCLUSION

PKC affected all three major races in our population with a high male to female ratio of 14:1. Seventy-nine percent of our cases were sporadic and 60% suffered dystonic posturing during attacks. Of the cases reviewed, 8% of patients with idiopathic PKC also had epilepsy.

An investigation of the spatial variations of the energetic trapped electrons at low altitudes

We have analyzed the trapped electron data (0.19-3.2 MeV) taken by the Japanese OHZORA satellite operated at 350-850 km altitude in polar orbit during 1984-1987 near solar minimum. The electron observations reveal all the global attributes of the quiet-time electron radiation belts, such is the South Atlantic Anomaly, the electron "slot", and the outer radiation belt regions. The electron data are in general agreement with the NASA AE-8 electron model, but there are differences, particularly with respect to distinctive local-time variations in the slot region. In this paper, we present results from analyses of variations of the electron pitch angle distributions with local time, L-shell and altitude.

Interleukin-1beta induction of mitogen-activated protein kinases in human mesangial cells. Role of oxidation

Interleukin-1beta (IL-1beta) significantly influences renal cellular function through the induction of several gene products. The molecular mechanisms involved in gene regulation by IL-1beta are poorly understood; however, the appearance of novel tyrosine phosphoproteins in IL-1beta-treated cells suggests that IL-1beta may function through tyrosine phosphoprotein intermediates. The mitogen-activated protein (MAP) kinases are tyrosine phosphoproteins that could potentially mediate the effects of IL-1beta. Protein tyrosine phosphorylation following IL-1beta treatment may be dependent on redox changes since the IL-1beta receptor is not a protein-tyrosine kinase and oxidation has been shown to induce tyrosine phosphorylation. In this report we demonstrate that conditioning human glomerular mesangial cells with IL-1beta results in the tyrosine phosphorylation and activation of two members of the MAP kinase family, extracellular signal-regulated protein kinase 2 (ERK2) and p54 Jun-NH2-terminal kinase (JNK). This effect of IL-1beta is abrogated by pretreating cells with the antioxidants N-acetyl-L-cysteine or dithiothreitol. Furthermore, the effects of IL-1beta on ERK and JNK activation are reproduced by treating mesangial cells with membrane-permeable oxidants. IL-1beta and oxidants also cause phosphorylation and activation of the upstream ERK regulatory element MAP kinase kinase. Interestingly, IL-1beta, but not exogenous oxidants, causes phosphorylation of the upstream JNK activator, JNK kinase. These data indicate that IL-1beta activates ERK2 through an oxidation-dependent pathway. Exogenous oxidants and IL-1beta activate JNK through different upstream mechanisms; however, antioxidant inhibition of JNK activation indicates that endogenous oxidants may play a role in IL-1beta-induced JNK activation. Thus IL-1beta may affect mesangial cell function by activating MAP kinases, which can then regulate gene transcription. Furthermore, reactive oxygen species released during inflammatory glomerular injury may also affect mesangial function through a MAP kinase signal.

Modulation of IL-1-induced chemokine expression in human mesangial cells through alterations in redox status

The effects of altering intracellular redox potential on interleukin 1 (IL-1)-induced MCP-1 gene expression by human mesangial cells were examined. Thiol containing antioxidants significantly increased cellular glutathione content while decreasing glutathione disulfide levels. These antioxidants inhibited IL-1 induction of MCP-1 mRNA expression. This correlated with a decrease in DNA binding activity of NF-kappa B, a transcription factor thought to be necessary for MCP-1 gene expression. Incubation of mesangial cells with the oxidizing agents diamide or hydrogen peroxide did not upregulate MCP-1 gene expression, and prevented IL-1 induction of MCP-1 mRNA. Oxidants appeared to inhibit the degradation of I kappa B, and the translocation of NF-kappa B to the nucleus. Non-oxidative depletion of intracellular glutathione also attenuated the effects of IL-1 on MCP-1 expression. These data indicate that the intracellular redox potential is a critical determinant of cell activation by IL-1. The observation that both oxidizing and reducing environments are inhibitory suggests that redox changes can affect the IL-1 signal transduction pathway at multiple points.

Fc(gamma) receptor cross-linking induces peripheral blood mononuclear cell monocyte chemoattractant protein-1 expression: role of lymphocyte Fc(gamma)RIII

Immune complexes activate cells by cross-linking leukocyte surface Fc(gamma)Rs. Diseases associated with immune complex deposition, such as rheumatoid arthritis, glomerulonephritis, or idiopathic pulmonary fibrosis, are characterized by compartmentalized monocyte infiltration. The factors that recruit monocytes to these compartments are not well characterized; however, monocyte chemoattractant protein-1 (MCP-1) has been found in areas of tissue injury. To account for these observations we hypothesized that PBMC Fc(gamma)R cross-linking may induce MCP-1 synthesis, which stimulates further monocyte recruitment. To test this hypothesis, PBMC were incubated on increasing concentrations of immobilized human IgG, a stimulus for Fc(gamma)R cross-linking. Immunoreactive MCP-1 was produced in a dose-dependent manner (p &lt; 0.0001). MCP-1 was specifically induced by Fc(gamma)R cross-linking, since immobilized F(ab')2 fragments of human IgG did not activate MCP-1 production. This effect was reproduced by directly cross-linking PBMC Fc(gamma)RIII, but not by cross-linking Fc(gamma)RI or Fc(gamma)RII. PBMC-derived MCP-1 stimulated monocyte chemotaxis that was inhibited by a neutralizing anti-MCP-1 Ab. MCP-1 levels correlated with increased PBMC mRNA expression. Interestingly, Fc(gamma)R cross-linking with either immobilized IgG or anti-Fc(gamma)RIII induced more MCP-1 release from PBMC than from autologous monocytes (p = 0.02). Lymphocytes, the main cell type found in PBMC preparations, did not independently produce a significant amount of MCP-1, but when incubated on immobilized IgG or anti-Fc(gamma)RIII secreted a soluble factor(s) that induced monocyte MCP-1 production. These data suggest that cross-linking PBMC Fc(gamma)R induces the production of bioactive MCP-1. This occurs in part at the level of gene transcription and involves a cooperative interaction between monocytes and lymphocytes.

Fc(gamma) receptor cross-linking induces peripheral blood mononuclear cell monocyte chemoattractant protein-1 expression: role of lymphocyte Fc(gamma)RIII

Immune complexes activate cells by cross-linking leukocyte surface Fc(gamma)Rs. Diseases associated with immune complex deposition, such as rheumatoid arthritis, glomerulonephritis, or idiopathic pulmonary fibrosis, are characterized by compartmentalized monocyte infiltration. The factors that recruit monocytes to these compartments are not well characterized; however, monocyte chemoattractant protein-1 (MCP-1) has been found in areas of tissue injury. To account for these observations we hypothesized that PBMC Fc(gamma)R cross-linking may induce MCP-1 synthesis, which stimulates further monocyte recruitment. To test this hypothesis, PBMC were incubated on increasing concentrations of immobilized human IgG, a stimulus for Fc(gamma)R cross-linking. Immunoreactive MCP-1 was produced in a dose-dependent manner (p < 0.0001). MCP-1 was specifically induced by Fc(gamma)R cross-linking, since immobilized F(ab')2 fragments of human IgG did not activate MCP-1 production. This effect was reproduced by directly cross-linking PBMC Fc(gamma)RIII, but not by cross-linking Fc(gamma)RI or Fc(gamma)RII. PBMC-derived MCP-1 stimulated monocyte chemotaxis that was inhibited by a neutralizing anti-MCP-1 Ab. MCP-1 levels correlated with increased PBMC mRNA expression. Interestingly, Fc(gamma)R cross-linking with either immobilized IgG or anti-Fc(gamma)RIII induced more MCP-1 release from PBMC than from autologous monocytes (p = 0.02). Lymphocytes, the main cell type found in PBMC preparations, did not independently produce a significant amount of MCP-1, but when incubated on immobilized IgG or anti-Fc(gamma)RIII secreted a soluble factor(s) that induced monocyte MCP-1 production. These data suggest that cross-linking PBMC Fc(gamma)R induces the production of bioactive MCP-1. This occurs in part at the level of gene transcription and involves a cooperative interaction between monocytes and lymphocytes.

Audit of 149 consecutive carotid endarterectomies performed by a single surgeon in a district general hospital over a 12-year period

Carotid endarterectomy has been established by two large randomised controlled trials (European Carotid Surgery Trial (ECST) and North American Symptomatic Carotid Endarterectomy Trial (NASCET)) as an important surgical procedure for the prevention of ischaemic strokes in patients presenting with transient cerebral ischaemia or non-disabling strokes attributable to severe ipsilateral carotid artery stenosis. The operation carries significant risk of death and stroke and it has been advocated by some that carotid endarterectomy should only be performed in a small number of designated regional centres in order to achieve good surgical results. It is doubtful that the regional centres alone can cope with the increasing numbers of patients requiring carotid endarterectomy and there is therefore a requirement for the procedure to be carried out by vascular surgeons in district general hospitals. It is important that surgical results are audited to ensure that comparable outcomes are achieved. We present an audit of our experience of carotid endarterectomy since 1981. A total of 149 consecutive carotid endarterectomies were performed by a single surgeon with a special interest in carotid surgery. The results are comparable to ECST with a 30-day mortality of 0% and an overall 30-day stroke rate of 5.7% (major strokes) for patients with severe, ie 70-99%, ipsilateral carotid artery stenoses. We have shown that carotid endarterectomy is an operation that can be performed safely and with good results by suitably trained surgeons in district general hospitals.

Monocyte chemoattractant protein-1 levels in patients with glomerular disease

Chemokines such as monocyte chemoattractant protein-1 (MCP-1) and interleukin-8 have been implicated in recruiting leukocytes to the glomerulus during immune renal injury. To detect the expression of MCP-1 in human glomerular disease, we measured urinary MCP-1 levels in patients with a variety of glomerulopathies. These data demonstrated that MCP-1 was present in the urine of patients with glomerular disease and that patients with inflammatory glomerulopathies had higher levels of urinary MCP-1. Urinary MCP-1 correlated with the extent of proteinuria (r = 0.71, P < 0.0001), but not with serum MCP-1 levels (r = 0.14, P > 0.3). The MCP-1 present in urine was biologically active, increasing monocyte migration in a microchemotaxis assay. This activity was attenuated by the addition of anti-MCP-1 antibody to the samples. Enumerating glomerular macrophages demonstrated that glomerular inflammation was correlated with urinary MCP-1 levels (r = 0.53, P < 0.02). Individuals with light microscopic evidence of severe glomerular injury (ie, crescents, necrosis, endocapillary proliferation) had significantly higher levels of MCP-1 in their urine than patients with less severe glomerular changes (1,962 +/- 612 pg MCP-1/mg creatinine v 314 +/- 45 pg MCP-1/mg creatinine; P < 0.002). Taken together, these results suggest that urinary MCP-1 reflects the extent to which MCP-1 that is produced in the glomerulus participates in the glomerular inflammatory response.

Induction of cyclin A gene expression by homocysteine in vascular smooth muscle cells

Homocysteine is an important and independent risk factor for arteriosclerosis. We showed previously that homocysteine stimulates vascular smooth muscle cell proliferation, a hallmark of arteriosclerosis. We show here that homocysteine and serum increased DNA synthesis synergistically in both human and rat aortic smooth muscle cells (RASMCs). Treatment of quiescent RASMCs with 1 mM homocysteine or 2% calf serum for 36 h increased cyclin A mRNA levels by 8- and 14-fold, respectively, whereas homocysteine plus serum increased cyclin A mRNA levels by 40-fold, indicating a synergistic induction of cyclin A mRNA. Homocysteine did not increase the half-life of cyclin A mRNA (2.9 h), but it did increase the transcriptional rate of the cyclin A gene in nuclear run-on experiments. The positive effect of homocysteine on cyclin A gene transcription was confirmed by our finding that homocysteine increased cyclin A promoter activity and ATF-binding protein levels in RASMCs. Finally, 1 mM homocysteine increased cyclin A protein levels and cyclin A-associated kinase activity by threefold. This homocysteine-induced expression lesions by promoting proliferation of vascular smooth muscle cells.

Activation of nuclear factor-kappa B correlates with MCP-1 expression by human mesangial cells

Emerging evidence suggests that mesangial cell-derived monocyte chemoattractant protein-1 (MCP-1) is a potentially important mediator of glomerular monocyte infiltration. Interleukin-1 beta (IL-1) has been found in glomeruli during inflammation, and is a potent inducer of MCP-1 expression by mesangial cells. Analysis of the promoter region of the human MCP-1 gene demonstrates several putative binding sites for transcription activating factors, including recognition elements for the IL-1-inducible transcription factor, nuclear factor-kappa B (NF-kappa B). This study investigated the role of NF-kappa B in IL-1-induced MCP-1 expression by human mesangial cells. We found that treating mesangial cells with IL-1 resulted in the rapid activation (within 30 min) and nuclear translocation of NF-kappa B. NF-kappa B activation could be blocked by preventing the proteolytic degradation of I kappa B, the cytoplasmic inhibitor of NF-kappa B, with the protease inhibitor tosyl-phe-chloromethylketone (TPCK). Inhibition of NF-kappa B with TPCK correlated with a dose-dependent reduction in IL-1-induced MCP-1 mRNA levels. Conversely, raising intracellular cyclic-AMP levels, or exposing mesangial cells to herbimycin A, treatments that block IL-1-induced MCP-1 mRNA expression, significantly attenuated NF-kappa B activation. Finally, blocking the synthesis of one of the protein subunits of NF-kappa B with an antisense oligonucleotide decreased MCP-1 mRNA levels in response to IL-1. These data suggest that MCP-1 gene transcription may be mediated, in part, by the transcription factor NF-kappa B.

Cyclic adenosine monophosphate and protein kinase C modulate fibronectin production in cultured human mesangial cells

To identify potential intracellular mediators of mesangial cell fibronectin production, we examined the effect of cyclic adenosine monophosphate and protein kinase C on fibronectin biosynthesis in cultured human mesangial cells. We found that increasing intracellular cyclic adenosine monophosphate resulted in a 2.6-fold increase in fibronectin mRNA expression within 15 minutes; this reached a plateau after 1 hour and fell below control levels by 24 hours. Cyclic adenosine monophosphate significantly increased both immunoreactive fibronectin levels and the incorporation of [35S]-labeled methionine into fibronectin after 1 and 2 hours (251% +/- 3% and 157% +/- 18% of controls, respectively). The induction of protein kinase C with phorbol ester also increased fibronectin mRNA expression. The effect was time and dose dependent. Phorbol ester significantly increased both immunoreactive fibronectin levels and the incorporation of [35S]-labeled methionine after 1 and 2 hours (174% +/- 2% and 224% +/- 6% of controls, respectively). Inhibition of protein kinase C with calphostin C attenuated constitutive and phorbol ester induced fibronectin biosynthesis. These studies indicate that cyclic adenosine monophosphate and protein kinase C regulate mesangial cell fibronectin biosynthesis and that protein kinase C may contribute to control of constitutive fibronectin production.

Role of protein kinase pathways in IL-1-induced chemoattractant expression by human mesangial cells

Human mesangial cells produce the monocyte-specific chemotactic factor monocyte chemoattractant protein-1 (MCP-1) in response to a variety of stimuli, including the pro-inflammatory cytokine interleukin-1 beta (IL-1). The intracellular signals responsible for mediating the effects of IL-1 on MCP-1 expression in human mesangial cells have not been defined. Evidence from other types of cells suggests that protein kinases are involved in MCP-1 gene regulation. We investigated the role of protein kinase pathways in mediating IL-1-induced MCP-1 expression. Activation of protein kinase C (PKC) by phorbol esters or diacyglycerol up-regulated mesangial MCP-1 message and bioactivity in a fashion similar to IL-1. However, while inhibition of PKC activity completely blocked phorbol-induced MCP-1 up-regulation, induction by IL-1 was not prevented. Inhibitors of cyclic AMP (cAMP)-dependent protein kinase (PKA) also failed to block IL-1-induced MCP-1 expression. Furthermore, increasing intracellular cAMP and activating PKA attenuated basal MCP-1 mRNA levels by 82% and blocked IL-1 induced MCP-1 expression by 88%. Finally, the role of protein tyrosine kinases was studied. The structurally distinct protein tyrosine kinase (PTK) inhibitors genistein, herbimycin A, and tyrphostin each caused a dose-dependent inhibition of the effects of IL-1 on mesangial MCP-1 activity. IL-1 treatment of mesangial cells resulted in the up-regulation of three tyrosine phosphoproteins with apparent molecular masses between 40 and 62 kD. These results suggest that the effects of IL-1 on MCP-1 expression are not mediated through PKC or cAMP-PKA, but may be transduced through PTKs.

Liquid chromatographic study of solute hydrogen bond basicity

The purpose of the present work was to investigate a liquid chromatographic method for the measurement of relative hydrogen bond basicities of dilute species. This type of determination cannot be done with conventional reversed-phase liquid chromatography due to the silanophilic interactions of basic solutes with the silica packing material. The studies were done on a polymeric stationary phase with pendant phenol groups that act as powerful hydrogen bond donors. Solute retention was evaluated in terms of two hydrogen bond basicity scales, beta 2H and beta 2C, and a steric hindrance parameter, Es. beta 2H and beta 2C are basicity scales based on the free energy of forming 1:1 hydrogen bond complexes and the retention on a strong hydrogen bond donor gas chromatographic phase, respectively. The Es parameter characterizes the steric effect experienced by the solute acceptor site. It is shown that retention correlates very strongly with beta 2H and less strongly with beta 2C. The log k' values need only two descriptive parameters, i.e., beta 2H and Es, to give a good fit. As a whole, retention on the phenolic polymeric phase provides an efficient method for the measurement of relative hydrogen bond basicities.

Low energy laser therapy for treatment of post-herpetic neuralgia

Post-herpetic neuralgia is a significant and severe disability that afflicts some patients following the acute manifestation of the disease despite what may be considered adequate pharmacological treatment at the time of onset of the vesicular rash. Surgery in general has little to offer in this condition although dorsal route entry zone lesions may be appropriate in some situations. Low dose laser therapy has been of value in a small series, to date, of cases that the treatment has been used on. This has been both in the early phase soon after the vesicles have cleared and often late, many years after the onset of the pain. Reported is a good improvement rate in approximately 60% of cases. The treatment is non-invasive and consideration of initial laser therapy is advocated.

LDL stimulates mesangial fibronectin production and chemoattractant expression

Hyperlipidemia has been associated with glomerulosclerosis and a glomerular monocyte infiltrate in models of progressive renal insufficiency. The pathogenesis of hyperlipidemia-induced renal injury remains unknown. We postulated that the effect of hyperlipidemia may be mediated through LDL-induced activation of mesangial cells, which have recently been shown to possess LDL receptors. To test this hypothesis, cultured human mesangial cells were co-incubated with human LDL. Monolayers treated with LDL demonstrated a greater level of tissue culture supernatant fibronectin than control mesangial cells. This correlated with enhanced expression of fibronectin mRNA in LDL-treated mesangial cells. Additionally, LDL conditioning of mesangial cells caused a dose- and time-dependent increase in the expression of monocyte chemoattractant protein-1 mRNA, a monocyte specific chemotactic factor, as well as an increase in the monocyte chemotactic activity of mesangial supernatants. Thus, the deleterious effects of hyperlipidemia on the kidney may be mediated by the mesangial cell through an increase in production of mesangial matrix and recruitment of inflammatory cells to the glomerulus.

Astrocytoma and associated arteriovenous malformation

A case is reported of a cerebral arteriovenous malformation occurring in continuity with an astrocytoma. Possible etiologies of this unusual association are discussed.

The impact of continuous electrophysiological monitoring on preservation of the facial nerve during acoustic tumour surgery

Continuous electromyographic (EMG) activity and responses to electrical stimulation of the facial nerve were monitored intraoperatively in 35 patients undergoing primary removal of acoustic neuroma. The rate of anatomical and immediate functional preservation of the facial nerve of these patients was compared with a matched population where a facial nerve stimulator and monitoring of facial muscle contraction by the anaesthetist only was employed. Overall, 94% (n = 33) of facial nerves were preserved anatomically in patients with continuous EMG monitoring, compared with 64% (n = 89) of patients (n = 139) without continuous monitoring. Amongst the 33 cases with anatomical facial nerve preservation, 64% (n = 21) had immediate functional preservation. Immediate functional preservation was only achieved in 39% (n = 35) of anatomically preserved facial nerves (n = 89) where conventional monitoring was used.

Ventilatory function among metal workers in Singapore

The ventilatory function of 634 workers in small scale metal working industries was evaluated. Almost five percent (4.7%) of the workers were found to have FEV1.0/FVC ratio of less than 75%. Compared with the lung function of industrial workers reported by Zee, 10.9% were found to have low ventilatory function. Comparison of the ventilatory function obtained from the metal workers with those of occupational groups previously reported shows that the metal workers have lower FVC and FEV1.0 values. Mid and end expiratory flow rates were also measured. These measures have been shown to be very sensitive in detecting obstructions in small airways. It is recommended that future studies should be carried out to obtain ventilatory functions for the normal population. The values reported here of FEV25%-75% and FEF75%-85% would be useful for future investigations in forced expiratory flow rates.