Effect of training on time efficiency and marginal adaptation of computer-aided design/computer-aided manufacturing crowns among dental students

INTRODUCTION

The computer-aided design/computer-aided manufacturing (CAD/CAM) technology has revolutionised dentistry at present. An operator's skills can affect the overall clinical duration and marginal accuracy of the prosthesis fabricated through this workflow. The aim of this study was to assess the effect of CAD/CAM hands-on training compared with that of a self-instructional video on the performance of dental students in digital impression and fabrication of a CAD/CAM crown.

METHODS

In this cross-sectional study, 30 undergraduate dental students were shown a CEREC demonstration video. Each operator then captured a digital impression using the intra-oral scanner, and a crown was subsequently milled. All participants underwent a training course before repeating the process. Marginal discrepancy for each crown on its abutment tooth was measured before and after training using a stereomicroscope and was evaluated using Wilcoxon signed rank test. The duration taken for the process was recorded before and after training and evaluated using paired t-test.

RESULTS

The overall mean ±standard deviation marginal adaptation for the CEREC crowns was 78.15 ± 42.83 μm before training and 52.41 ± 17.12 μm after training. The Wilcoxon signed rank test found significant difference (p < .05) in terms of marginal adaptation of crowns fabricated before and after training. Paired t-tests showed that the time efficiency after training significantly improved compared with that before training.

CONCLUSIONS

Training with guided feedback is crucial to improve the time efficiency of making a digital impression and marginal adaptation of fixed prosthesis using the CAD/CAM technology.

Demographics and outcome of patients with congenital haemophilia in Sarawak, Malaysia

INTRODUCTION

Sarawak has a population that is geographically and characteristically widely varied. This study aimed to determine the demographic profile of patients in Sarawak, Malaysia. Materials and Methods - A cross-sectional study was conducted in 2019 at four major haemophilia treatment centres in Kuching, Sibu, Bintulu and Miri Hospitals, Sarawak. Demographic and clinical data were collected with consents from patients.

RESULTS AND DISCUSSION

Ninety-six haemophilia patients were identified - 79(82.3%) haemophilia A(HA) and 17(17.7%) haemophilia B(HB). Severe haemophilia patients were noted in 45.6% (36/79) of HA and 64.7% (11/17) of HB. In all 44.3% of the HA and 52.9% of the HB population had no identifiable family history of haemophilia. Two-thirds of the patients with severe HA were on prophylaxis [24/36 (66.7%)] and only onethird [4/11 (36.4%)] in severe HB. Inhibitors developed in 9/79 (11.4%) of the HA population [3/79 (3.8%) high responders]. The median inhibitor titre was not significantly different between the different treatment groups - on demand versus prophylaxis (1.0BU versus 2.0BU; z statistic -1.043, p-value 0.297, Mann-Whitney test). None of the patients developed inhibitory alloantibodies to factor IX. Four HA patients (5.1%) underwent immune tolerance induction where one case had a successful outcome. Three severe HA patients received emicizumab prophylaxis and showed remarkable reduction in bleeding events with no thromboembolic events being reported. One female moderate HA patient received PEGylated recombinant anti-haemophilic factor. Eleven patients underwent radiosynovectomy. One mild HB patient succumbed to traumatic intracranial bleeding. Our data reported a prevalence (per 100,000 males) of 5.40 cases for all severities of HA, 2.46 cases for severe HA; 1.16 cases for all severities of HB, and 0.75 cases for severe HB. The overall incidence of HA and HB was 1 in 11,500 and 1 in 46,000, respectively.

CONCLUSION

This study outlines the Sarawakian haemophilia landscape and offers objective standards for forward planning. Shared responsibilities among all parties are of utmost importance to improve the care of our haemophilia population.

Successfully endoscopic retrieval of ingested toothpicks in colorectum : a report of four cases

BACKGROUND

Toothpick ingestion is a rare event, but due to the low efficacy of radiographic examination, it can induce severe complications including perforation, abscess, and sepsis.

CASE REPORT

Four patients with either defecation problems or abdominal/anal pain were admitted to our hospital. Colonoscopy showed all four cases had a toothpick impacted in the colorectal wall without perforation. Direct retrieval of the toothpick under endoscopy was achieved. All four patients were relieved and remained well during the follow-up.

CONCLUSION

Endoscopy is the most effective method to discover or retrieve ingested wooden foreign bodies when there are no severe complications.

[Evaluation of the application of moving epidemic method on making influenza epidemic thresholds in the 7 climate zones in China]

Objective: We planned to evaluate the effectiveness of moving epidemic method (MEM) in calculating influenza epidemic threshold of 7 climatic zones in China mainland. Methods: The positive rate of influenza virus was obtained from the National Influenza Surveillance Network System from 2010/2011 to 2017/2018. We divided the 31 provinces into 7 climatic zones according to previous literatures and applied MEM to calculate the influenza epidemic threshold of 2018/2019 influenza season for these climatic zones. Sensitivity, specificity, positive predictive value and negative predictive value were calculated to evaluate the effectiveness of MEM. Results: Pre-epidemic threshold (the positive rate of influenza virus) varied from 9.66% (temperate zone) to 16.36% (subtropical zone) for 2018/2019 influenza season. The gap between pre-epidemic and post-epidemic thresholds was less than 5% except for plateau zone. The sensitivity was 86.16% (95CI:66.81%-98.23%), the specificity was 94.92% (95CI: 91.13%-98.41%), the positive predictive value was 89.87% (95%CI: 84.39%-94.38%), the negative predictive value was 92.96% (95%CI: 84.46%-99.17%). Conclusion: Overall, moving epidemic Method performs well in calculating influenza epidemic threshold in China, much better than the previous study.

Comparison between tunneling and standard endoscopic submucosal dissection for treatment of large esophageal superficial neoplasm

BACKGROUND AND STUDY AIMS

Endoscopic submucosal dissection (ESD) has been established as a standard endoscopic method for treating esophageal superficial neoplasms, and it can be performed using a conventional or a tunneling method. The aim of the present study was to compare the safety and efficacy of tunneling ESD (t-ESD) and standard ESD (s-ESD) for treating large esophageal superficial neoplasms and to explore the risk factors for postoperative strictures.

PATIENTS AND METHODS

Fifty-five consecutive patients with large esophageal superficial neoplasms were treated by t-ESD or s-ESD. Demographics, lesion characteristics, procedure-related parameters, and follow-up results were retrospectively collected to compare the efficacy and safety of these procedures. Multivariate analyses were conducted to determine the potential risk factors for postoperative strictures.

RESULTS

Of the 55 patients, 13 underwent t-ESD and 42 underwent s-ESD. The dissection speed of t-ESD was significantly faster than that of s-ESD (7.42±1.99 min/cm2 vs. 9.01±2.11 min/cm2, P<0.05). En bloc resection was achieved in 98.2% (54/55) of the cases, while R0 resection was achieved in 92.7% (51/55). Curative resection was achieved in 78.2% (43/55) of the cases. Fourteen patients (25.5%) had postoperative strictures, which resolved with endoscopic dilation and/or stent insertion. Circumferential involvement of >3/4 and lesion length of >3 cm were independent risk factors for strictures.

CONCLUSIONS

T-ESD is a safe and effective method for treating large esophageal superficial neoplasms with a faster dissection speed than s-ESD, but postoperative strictures may be encountered for lesions involving more than three-fourths of the circumference or longer than 3 cm.

[Technical guidelines for seasonal influenza vaccination in China, 2018-2019]

Seasonal influenza vaccination is the most effective way to prevent influenza virus infection and its complications. Currently, China has licensed trivalent (IIV3) and quadrivalent inactivated influenza vaccine (IIV4), including split-virus influenza vaccine and subunit vaccine. In most parts of China, influenza vaccine is a category Ⅱ vaccine, which means influenza vaccination is voluntary, and recipients need to pay for it. To strengthen the technical guidance for prevention and control of influenza and the operational research on influenza vaccination in China, the National Immunization Advisory Committee (NIAC), Influenza Vaccine Technical Working Group (TWG), updated the 2014 technical guidelines and compiled the "Technical guidelines for seasonal influenza vaccination in China (2018-2019)" , based on most recent existing scientific evidences. The main updates include: epidemiology and disease burden of influenza, types of influenza vaccines, northern hemisphere influenza vaccination composition for the 2018-2019 season, and, IIV3 and IIV4 vaccines'major immune responses, durability of immunity, immunogenicity, vaccine efficacy, effectiveness, safety, cost-effectiveness and cost-benefit. The recommendations include: Points of Vaccination clinics (PoVs) should provide influenza vaccination to all persons aged 6 months and above who are willing to be vaccinated and do not have contraindications. No preferential recommendation is made for any influenza vaccine product for persons who can accept ≥1 licensed, recommended, and appropriate products. To decrease the risk of severe infections and complications due to influenza virus infection among high risk groups, the recommendations prioritize seasonal influenza vaccination for children aged 6-60 months, adults ≥60 years of age, persons with specific chronic diseases, healthcare workers, the family members and caregivers of infants <6 months of age, and pregnant women or women who plan to pregnant during the influenza season. Children aged 6 months to 8 years old require 2 doses of influenza vaccine administered a minimum of 4 weeks apart during their first season of vaccination for optimal protection. If they were vaccinated in previous influenza season, 1 dose is recommended. People ≥ 9 years old require 1 dose of influenza vaccine. It is recommended that people receive their influenza vaccination by the end of October. Influenza vaccination should be offered as soon as the vaccination is available. Influenza vaccination should continue to be available for those unable to be vaccinated before the end of October during the whole season. Influenza vaccine is also recommended for use in pregnant women during any trimester. These guidelines are intended for CDC members who are working on influenza control and prevention, PoVs members, healthcare workers from the departments of pediatrics, internal medicine, and infectious diseases, and members of maternity and child care institutions at all levels.

[Technical guidelines for seasonal influenza vaccination in China (2018-2019)]

Seasonal influenza vaccination is the most effective way to prevent influenza virus infection and complications from infection. Currently, China has licensed trivalent inactivated influenza vaccine (IIV3) and quadrivalent inactivated influenza vaccine (IIV4), including split-virus influenza vaccine and subunit vaccine. Except for a few major cities, influenza vaccine is a category Ⅱ vaccine, which means influenza vaccination is voluntary, and recipients must pay for it. To strengthen the technical guidance for prevention and control of influenza and operational research on influenza vaccination in China, the National Immunization Advisory Committee (NIAC) Influenza Vaccine Technical Working Group (TWG), updated the 2014 technical guidelines and compiled the "Technical guidelines for seasonal influenza vaccination in China (2018-2019)" . The main updates in this version include: epidemiology, disease burden, types of influenza vaccines, northern hemisphere influenza vaccination composition for the 2018-2019 season, IIV3 and IIV4 immune response, durability of immunity, immunogenicity, vaccine efficacy, effectiveness, safety, cost-effectiveness and cost-benefit. The influenza vaccine TWG provided the recommendations for influenza vaccination for the 2018-2019 influenza season based on existing scientific evidence. The recommendations described in this report include the following: Points of Vaccination clinics (PoVs) should provide influenza vaccination to all persons aged 6 months and above who are willing to be vaccinated and do not have contraindications. No preferential recommendation is made for one influenza vaccine product over another for persons for whom more than one licensed, recommended, and appropriate product is available. To decrease the risk of severe infections and complications due to influenza virus infection among high risk groups, the recommendations prioritize seasonal influenza vaccination for children aged 6-59 months, adults ≥60 years of age, persons with specific chronic diseases, healthcare workers, the family members and caregivers of infants <6 months of age, and pregnant women or women who plan to become pregnant during the influenza season. Children aged 6 months through 8 years require 2 doses of influenza vaccine administered a minimum of 4 weeks apart during their first season of vaccination for optimal protection. If they were vaccinated in 2017-2018 influenza season or a prior season, 1 dose is recommended. People more than 8 years old require 1 dose of influenza vaccine. It is recommended that people receive their influenza vaccination by the end of October. Influenza vaccination should be offered as soon as the vaccination is available. For the people unable to be vaccinated before the end of October, influenza vaccination will continue to be offered for the whole season. Influenza vaccine is also recommended for use in pregnant women during any trimester. These guidelines are intended for use by staff members of the Centers for Disease Control and Prevention at all levels who work on influenza control and prevention, PoVs staff members, healthcare workers from the departments of pediatrics, internal medicine, and infectious diseases, and staff members of maternity and child care institutions at all levels.

Abstract P1-09-10: Pathological complete response to neoadjuvant trastuzumab is dependent on HER2/CEP17 ratio in HER2-amplified early breast cancer

Purpose To evaluate whether pathological complete response to neoadjuvant trastuzumab is dependent on the level of HER2 amplification.

Patients and Methods 114 women with HER2-overexpressing early breast cancer who had received neo-adjuvant trastuzumab in the prospective ABCSG-24 and ABCSG-32 trials, and for whom the HER2/CEP17 ratio was available, were included in this analysis. The ratio was correlated with tumor response as measured by the three most commonly used definitions of pathological complete response: ypT0 ypN0, ypT0/is ypN0, and ypT0/is.

Results In trastuzumab-treated patients, ypT0 pN0 was achieved in 69.0% of patients with a HER2/CEP17 ratio of &gt;6, but only in 30.4% of tumors with a ratio of ≤6 (p=0.001, Chi Square test). When pCR was defined by ypT0/is pN0 or by ypTis, 75.9% and 82.8% of tumors with a high ratio had a complete remission, while only 39.1%, and 38.3% with a low ratio achieved a pCR (p=0.002 and p&lt;0.001, respectively). Logistic regression revealed that tumors with a higher HER2/CEP17 ratio had a significantly higher probability to achieve ypT0 ypN0 (OR: 5.08, 95% CI 1.86-13.90; p=0.002) than tumors with a low ratio, while none of the other clinicopathological parameters was predictive of pCR. The association between high HER2 amplification and pCR was almost exclusively confined to HR positive tumors (62.5% vs. 24.0%, 75.0% vs. 28.0%, and 87.5% vs. 28.0%, for ypT0 ypN0, ypT0/is ypN0, and ypT0/is; p=0.014, p=0.005, and p&lt;0.001), and was largely absent in HR negative tumors.

Conclusion A HER2/CEP17 ratio of &gt;6 in the pre-therapeutic tumor biopsy is associated with a significantly higher pCR rate particularly in HER2 / HR co-positive tumors, and can be used to predict outcome before neoadjuvant trastuzumab is initiated.

Citation Format: Singer CF, Tan YY, Fitzal F, Steger GG, Egle D, Reiner A, Rudas M, Gruber C, Bartsch R, Fridrik M, Seifert M, Exner R, Balic M, Bago-Horvath Z, Filipits M, Gnant M, For the Austrian Breast and Colorectal Cancer Study Group. Pathological complete response to neoadjuvant trastuzumab is dependent on HER2/CEP17 ratio in HER2-amplified early breast cancer [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P1-09-10.

[A survey of deployment of sidewalks in central urban areas of 12 cities, China]

Objective: To explore the deployment of sidewalks and the possible relationship with local GDP, population density and prosperity of streets in 12 cities selected in China. Methods: For all the streets in 333 blocks of 12 cities surveyed (Beijing, Tianjin, Shanghai, Qingdao, Hangzhou, Shaoxing, Suzhou, Nantong, Zhenjiang, Chengdu, Xining and Harbin), the deployment and management of sidewalks were observed. And we collected the GDP data of the 12 cities, the population data of 333 blocks, and the numbers of stores and restaurants along the streets. Results: A total of 4 255 streets were included in the study. In the 12 cities, 71.1% of the streets had sidewalks. The deployment rates of sidewalks was high in Qingdao (91.9%) and Harbin (90.6%), and low in Suzhou (48.6%) and Shaoxing (52.6%), the differences were significant. The higher GDP of city was, the more sidewalks were deployed. But on the other hand there were more parking cars and obstacles on the sidewalks. The higher the population density was, the worse the condition of sidewalks was. Conclusions: The survey of sidewalks in the 12 cities indicated that efforts could be made to improve the condition of sidewalks. Attention should be paid not only to the deployment of sidewalks, but also the management of sidewalks. Reasonable deployment of sidewalks should be considered according to the local population density and traffic flow.

Intravenous Fentanyl for Dyspnea at the End of Life: Lessons for Future Research in Dyspnea

OBJECTIVES

To determine the efficacy of intravenous (IV) Fentanyl in dyspnoeic patients with advanced cancer.

METHODS

Dyspnoeic patients with advanced cancer satisfying the selection criteria received (IV) Fentanyl and were evaluated for response 24 hours post-administration in a prospective observational study.

RESULTS

Altogether 36 patients were enrolled into the study. However, data from only 16 patients could be analysed as 20 patients had died or were too sick to self-report scores. Seven out of 16 patients responded to IV Fentanyl although the result was not statistically significant (non-responders versus responders: 56.3% vs 43.8%, p = 0.33). The strongest correlations for variables predictive of responder status were the absence of anxiety and lung metastases.

CONCLUSIONS

This exploratory study shows that IV Fentanyl can alleviate dyspnea in some patients but is an example of the difficulties conducting dyspnea research. Future studies would benefit from novel developments in the areas of measuring dyspnea in dying patients and statistical analysis of small sample sizes.

High-rate low-temperature growth of vertically aligned carbon nanotubes

We report the low-temperature growth of vertically aligned carbon nanotubes (CNTs) at high growth rates by a photo-thermal chemical vapour deposition (PTCVD) technique using a Ti/Fe bilayer film as the catalyst. The bulk growth temperature of the substrate is as low as 370 °C and the growth rate is up to 1.3 µm min(-1), at least eight times faster than the values reported by traditional thermal CVD methods. Transmission electron microscopy observations reveal that as-grown CNTs are uniformly made of highly crystalline 5-6 graphene shells with an approximately 10 nm outer diameter and a 5-6 nm inner diameter. The low-temperature rapid growth of CNTs is strongly related to the unique top-down heating mode of PTCVD and the use of a Ti/Fe bimetallic solid solution catalyst. The present study will advance the development of CNTs as interconnects in nanoelectronics, through a CMOS-compatible low-temperature deposition method suitable for back-end-of-line processes.

Reducing scanning electron microscope charging by using exponential contrast stretching technique on post-processing images

An exponential contrast stretching (ECS) technique is developed to reduce the charging effects on scanning electron microscope images. Compared to some of the conventional histogram equalization methods, such as bi-histogram equalization and recursive mean-separate histogram equalization, the proposed ECS method yields better image compensation. Diode sample chips with insulating and conductive surfaces are used as test samples to evaluate the efficiency of the developed algorithm. The algorithm is implemented in software with a frame grabber card, forming the front-end video capture element.

Knowledge and attitude of university students in health sciences on the prevention of cervical cancer

Cervical cancer is the second most common female cancer after breast cancer both in Malaysia and worldwide although it can be mostly prevented. The objective of this study was to assess the knowledge level and attitude of University Kebangsaan Malaysia female students in the Faculties of Pharmacy and Allied Health Sciences on the prevention of cervical cancer. A total of 675 respondents were recruited for this cross-sectional study involving pre-tested questionnaires. The data was analyzed using Statistical Package for Social Sciences (SPSS) version 15.0. There was significant association between grade and mean score of knowledge with different faculties and year of education (p<0.05). However, significant association was shown only between grade of knowledge with different programs in the Faculty of Allied Health Sciences. For mean score of knowledge, significant difference only existed among different races (p<0.05). Mass media was the most common source of information. In conclusion, the knowledge level of respondents on cervical cancer and its prevention was not satisfactory despite their positive attitude on prevention. Thus, more awareness programs should be conducted in University campuses to provide students with knowledge on prevention of cervical cancer.

Distribution of serotonin receptors and interacting proteins in the human sigmoid colon

This study aimed to examine the distribution of 5-HT receptors in the human colon. 5-HT induces desensitization of the circular muscle and as this is facilitated by G-protein coupled receptor kinases (GRKs) and other proteins, we also examined their distribution. Human sigmoid colon samples were dissected into three separate layers (mucosa, taeniae coli and intertaenial strips) and RNA was amplified by RT-PCR. The 5-HT(2B) receptor and all 5-HT(7) receptor splice variants were expressed in all tissues. 5-HT(4) a,b,c and n splice variants were also expressed in all tissues and 5-HT(4d), 5-HT(4g) and 5-HT(4i) were only detected in some samples. The 5-HT(2A) receptor was seen predominantly in the intertaenial strips of the colon. Only one transcript of the serotonin transporter (SERT) was detected in the muscle layers. Variation was seen in GRK expression with GRK2 and 3 predominantly expressed in the mucosa, while GRK5 and 6 were found more commonly in the taeniae coli. PDZ (named after postsynaptic density protein, Drosophila disc large tumour suppressor and tight junction protein ZO-1) domain containing proteins, which may be involved in 5-HT receptor trafficking, were also detected throughout the sigmoid colon. The 5-HT(3A) subunit was expressed in all tissues, whereas the 5-HT(3E) subunit was mainly found in the mucosa layer while the 5-HT(3B) subunit was more common in the muscle layers. Receptor interacting chaperone (RIC-3), which is involved in transporting 5-HT(3) receptor subunits, is expressed less in mucosa compared to muscle layers. In conclusion, these results show that there is variation in distribution of 5-HT receptors and interacting proteins within the sigmoid colon that may contribute to colonic function.

MRSA breast abscesses in postpartum women

BACKGROUND

Infections caused by community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA) are being increasingly observed in patients who lack traditional risk factors. While mastitis and breast abscesses are commonly encountered in post-natal women, CA-MRSA breast infections have rarely been reported.

MATERIALS AND METHODS

We reviewed 15 postpartum women with methicillin-resistant Staphylococcus aureus (MRSA) breast abscesses observed in our unit from June 2005 to April 2007. Ultrasonographic examination was performed in all cases. MRSA infection was diagnosed on microbiological analysis cultured from the abscesses of these patients.

RESULTS

The median age of the patients was 31.5 years. The majority of the patients were primiparae (80%). Only one patient was immunocompromised. None of the patients had history of previous breast infection and none developed recurrence. Eleven patients (73.3%) underwent aspiration of pus and four patients (26.7%) underwent incision and drainage. All the cultures were sensitive to co-trimoxazole and vancomycin. Eight (53.3%) of the cultures were also sensitive to erythromycin.

CONCLUSION

CA-MRSA is an emerging problem in our obstetric population. CA-MRSA breast infections are clinically responsive to common oral antibiotics such as co-trimoxazole and erythromycin. A high index of suspicion is essential to avoid delay in the clinical response to empirical beta-lactams as these patients may benefit from an early change of antibiotics.

Inadequate dietary calcium intake in elderly patients with hip fractures

INTRODUCTION

Calcium supplementation and pharmacotherapy are recommended in the preventive management of osteoporosis. Many previous studies report of underdiagnosis and undertreatment of osteoporosis among elderly patients with hip fractures. We undertook this study to determine the dietary calcium levels in our local elderly population who were admitted with hip fractures.

METHODS

77 patients, between the ages of 60 and 98 years of age, and admitted to our department between January 2001 and September 2001 for hip fractures, were studied. The dietary calcium intakes of these patients were determined by a food frequency questionnaire and a detailed diet history. Bone mineral density (BMD) studies were performed on 55 of these patients to confirm the diagnosis of osteoporosis.

RESULTS

The mean daily calcium intake was found to be 650 mg. Only six of our hip fracture patients (7.8 percent) had a daily calcium intake above the recommended levels of 1,000 mg per day. For the 55 patients who had BMD performed, only one patient had a BMD within the normal range. 34 patients (64.2 percent) had hip T-scores in the osteoporotic range and 18 patients (33.9 percent) had hip T-scores in the osteopenic range. We found that the patients with BMD in the osteoporotic and osteopenic ranges had no significant difference in the dietary calcium intake.

CONCLUSION

The dietary calcium intake of our elderly patients with hip fractures is insufficient. They would benefit from dietary education and calcium supplements to prevent deterioration in bone density and subsequent osteoporotic fractures.

Real-time image quality assessment with mixed Lagrange time delay estimation autoregressive (MLTDEAR) model

A proposal to assess the quality of scanning electron microscope images using mixed Lagrange time delay estimation technique is presented. With optimal scanning electron microscope scan rate information, online images can be quantified and improved. The online quality assessment technique is embedded onto a scanning electron microscope frame grabber card for real-time image processing. Different images are captured using scanning electron microscope and a database is built to optimally choose filter parameters. An optimum choice of filter parameters is obtained. With the optimum choice of scan rate, noise can be removed from real-time scanning electron microscope images without causing any sample contamination or increasing scanning time.

Selective modified radical neck dissection for papillary thyroid cancer-is level I, II and V dissection always necessary?

BACKGROUND

There is ongoing controversy as to the indications for and extent of lateral cervical lymphadenectomy for patients with papillary thyroid cancer (PTC). While most now agree that prophylactic lymph node dissections (LND) play no role, at the University of California, San Francisco (UCSF) we limit LND selectively on a level by level basis, and resect only the levels thought to harbor disease or to be at increased risk of metastases. This initial 'selective LND' usually includes levels III and IV (due to the well-documented increased likelihood of metastases to these levels) and levels I, II, and V are included when there is clinical or radiological evidence of disease or increased risk of it.

METHODS

A retrospective review of the clinical charts and hospital records of 106 consecutive patients who had metastatic PTC and who underwent at least one lateral cervical LND at UCSF between January 1995 and December 2003 was carried out. Data were collected to assess which patients had levels I, II, and/or V included in their initial ipsilateral and/or contralateral LND and to determine the recurrence rates at these levels if they had previously been excised compared with if they had not. Chi-squared and Fisher exact tests were utilized for statistical comparison, where appropriate.

RESULTS

A total of 140 initial lateral LND were performed: 104 ipsilateral and 36 contralateral. In these initial LND, 3.9%, 72.5%, and 18.6% of patients had levels I, II, and V resected on the ipsilateral side, and 2.9%, 60.0%, and 37.1% of patients had levels I, II, and V resected on the contralateral side. Recurrence at levels I and V was uncommon in all patient populations. Recurrence at level II was 19% ipsilaterally and 10% contralaterally when the level was previously resected and 21% ipsilaterally and 14% contralaterally when the level was not previously resected. There was no statistically significant difference in recurrence at level II when the level had previously been resected compared with when it had not.

CONCLUSIONS

If utilized in the appropriate patient population, a selective approach to lateral cervical LND for PTC can be a successful alternative to the routine modified radical LND. Levels I and V do not require resection unless there is clinical or radiological evidence of disease. Guidelines for which patients may be considered for this less aggressive approach to level II nodal metastases are suggested.

Predictors of axillary lymph node metastases in women with early breast cancer in Singapore

INTRODUCTION

The presence of axillary lymph node metastases is an important prognostic factor in breast cancer. Sentinel lymph node biopsy (SLNB) is an emerging method for the staging of the axilla. It is hoped that with SLNB, the morbidity from axillary lymph node dissection (ALND) can be avoided without compromising the staging and management of early breast cancer. However, only patients found to be SLNB negative benefit from this procedure, as those with positive SLNB may still require ALND. Our objective is to study the various clinico-pathological factors to find predictive factors for axillary lymph node involvement in early breast cancer. It is hoped that with these factors, we will be better able to identify groups of patients most likely to benefit from SLNB.

METHODS

A retrospective study of 380 early breast cancer cases (stage T1 and T2, N0, N1, M0) in women treated in the Department of General Surgery, Tan Tock Seng Hospital, between January 1999 and August 2002, was conducted. Incidence of nodal metastases was correlated with clinico-pathological factors, and analysed by univariate and multivariate analyses.

RESULTS

Approximately 35 percent of the 380 cases of early breast cancer had nodal metastases. Multivariate analyses revealed four independent predictors of node positivity: tumour size (p-value equals 0.0001), presence of lymphovascular invasion (p-value is less than 0.0001), tumours with histology other than invasive ductal or lobular carcinoma (p-value equals 0.04), and presence of progesterone receptors (p-value equals 0.05).

CONCLUSION

We have found independent preoperative predictive factors in our local population for the presence of nodal metastases. This information can aid patient selection for SLNB and improve patient counselling.

Influences of gender and region on responses to 5-HT in the rat small intestine

The aim of this study was to obtain more information regarding the 'atypical' 5-HT7 receptor of the rat jejunum. 5-HT7-induced contractions of the jejunum were elicited by 5-HT in the presence of ondansetron. Maximal responses were slightly larger in tissues from male compared to female rats of comparable age, with Emax values of 97.2 +/- 3.3 and 84.25 +/- 4.3% respectively compared to acetylcholine as an internal standard. However, the pEC50 values for 5-HT were not significantly different. The mRNA expression levels of the 5-HT7 receptor were similar in whole jejunum and longitudinal muscle tissues taken from males and females. It was also shown that the maximal response of the jejunum from male rats was larger than the responses from mid intestine and ileum. However, in female tissues, the Emax of the mid intestine was significantly larger than the ileum, but not different from the jejunum. The results provide further insights into the 'atypical' 5-HT7 receptor of the rat jejunum and are also useful in optimising the preparation for further studies.

Management delays for early gastric cancer in a country without mass screening

BACKGROUND/AIMS

To examine the symptoms of early gastric cancer and the time scale of management delays in a country without a mass screening program.

METHODOLOGY

Retrospective review of 44 patients with early gastric cancer.

RESULTS

Epigastric pain (63.3%) and gastrointestinal hemorrhage (27.3%) were the main symptoms found. Total delay was made up of patient delay (48.6%), doctor delay (25.5%) and treatment delay (25.9%). Median patient delay (from symptom onset to medical consult) was 30 days (inter-quartile range 2 to 365). Patient delay of more than 6 months was associated with patients aged 50 and younger (P = 0.04) and those presenting with pain (P = 0.05). Median doctor delay (consult to diagnosis) was 21 days (1 to 35) and median treatment delay (diagnosis to surgery) was 8 days (2 to 21). Doctor delay of more than 6 months was associated with a negative gastroscopy or barium meal in the previous 12 months (P = 0.03).

CONCLUSIONS

The detection of early gastric cancer at the symptomatic-detectable stage is possible and this potential window for diagnosis can be more than 1 year for up to one third of cases. Efforts to reduce management delays should be aimed at public education and improving the quality and accessibility of endoscopic evaluation.

In planta regulation of extension of an endophytic fungus and maintenance of high metabolic rates in its mycelium in the absence of apical extension

The fungus Neotyphodium lolii is an endophytic symbiont. It grows in the intercellular spaces of the perennial ryegrass Lolium perenne, producing secondary metabolites which enhance the fitness of the association over that of uninfected L. perenne. We report that the average number of hyphal strands in a given section of a leaf remains constant during the life of a leaf, indicating synchrony of leaf and hyphal extension, including cessation of hyphal extension when leaf extension ceases. We used a constitutively expressed reporter gene as an indicator of the mycelium's metabolic activity during and after hyphal extension. Reporter gene activity decreased when the mycelium stopped extending in liquid culture but not in planta. This indicates that in planta endophyte hyphae remain metabolically highly active when extension has ceased and throughout the life of the leaf they are colonizing. The behavior of the fungus in planta indicates the existence of signaling pathways which (i) synchronize the extension of leaf and hypha by regulating hyphal extension, (ii) suppress hyphal branching, and (iii) stop apical extension of fungal hyphae, without reducing the mycelium's metabolic activity. These signals may be crucial for the symbiosis, by allowing the endophyte to switch the focus of its metabolic activity from extension to the production of secondary metabolites.

[A implementation for digital scan converter(DSC) by using FPGA]

A design of a Digital Scan Converter(DSC) in B scanner and its implementation by using FPGA are presented in this paper, and some applied results are presented too here.

Solid phase synthesis and biological activity of rat relaxin

The peptide hormone relaxin was isolated in good yield from the ovaries of the pregnant rodent Rattus rattus using a simplified purification schedule. It was subjected to comprehensive chemical characterization to confirm both its purity and predicted composition. The peptide was also chemically synthesized by the solid phase procedure. The two chains comprising the hormone were each assembled by the Boc-polystyrene method and, following conventional purification, combined in solution to form the single intramolecular and two intermolecular disulfide bonds. Following purification, the synthetic rat relaxin was fully chemically characterized and shown to be indistinguishable from the native peptide including by secondary structure analysis using circular dichroism spectroscopy. The native and synthetic rat relaxins were shown to be equally biologically active in the in vitro rat uterine relaxation assay and had pEC50 values that were comparable to synthetic human H2 relaxin.

Melioidosis splenic abscess--an unusual presentation as osteomyelitis of rib

INTRODUCTION

We report an unusual case of splenic melioidosis abscess presenting as osteomyelitis.

CLINICAL PICTURE

A 74-year-old nondiabetic gentleman presents with a non-healing left chest wall abscess from osteomyelitis.

TREATMENT

He underwent rib resection and the infection was found to involve the underlying pleura, lung, adjacent stomach, liver and diaphragm with a splenic abscess. Splenectomy was performed. Histology showed suppurative granulomas and cultures grew Burkholderia pseudomallei.

OUTCOME

The patient recovered well with antibiotics.

CONCLUSION

Melioidosis should not be forgotten as a cause of chronic suppurative infections in our endemic population.

Novel strategy for the synthesis of template-assembled analogues of rat relaxin

The 'template-assembled synthetic protein' (TASP) concept provides a simple and elegant approach for the preparation of analogues that retain key structural elements. We have synthesized TASP molecules containing the putative active site of relaxin, a peptide that has similar structural features to insulin but a markedly different biological role. Two types of chemoselective thiol ligation strategies (thioether and thiazolidine) were used and compared. The synthetic pendant peptides contain an essential region for bioactivity that is located in the alpha-helical region of the relaxin B-chain. Depending on whether the thioether or the thiazolidine chemistry was used to attach the peptides to the template, the reacting amino acid was placed either at the C-terminus or N-terminus, respectively, thus allowing the choice of orientation relative to the carrier molecule. The template molecule consists of a decapeptide with two proline-glycine turns and four evenly spaced lysine residues that were functionalized with the appropriate chemical moiety. This allowed reaction with the appropriately derivatized peptides in solution. To improve the template ligation step using the thioether approach, a pendant peptide C-terminal cysteamine residue was used to reduce potential steric hindrance during conjugation. The design of the peptides as well as the synthetic strategy resulted in the acquisition of mimetics showing weak non-competitive and weak competitive antagonist properties.

Quantitative autoradiographic studies of relaxin binding in rat atria, uterus and cerebral cortex: characterization and effects of oestrogen treatment

The binding characteristics of the relaxin receptor in rat atria, uterus and cortex were studied using a [33P]-labelled human gene 2 relaxin (B33) and quantitative receptor autoradiography. The binding kinetics of [33P]-human gene 2 relaxin (B33) were investigated in slide-mounted rat atrial sections. The binding achieved equilibrium after 60 min incubation at room temperature (23+/-1 degrees C) and dissociated slowly. The association and dissociation rate constants were 4.31+/-0.34x10(8) M(-1) x min(-1) and 1.55+/-0.38x10(-3) min(-1) respectively. Thus, the kinetic dissociation constant was 3.46+/-0.59 pM. Binding was saturable to a single population of non-interacting sites throughout atria, in uterine myometrium and the 5th layer of cerebral cortex. The binding affinities (pK(D)) of [33P]-human gene 2 relaxin (B33) were 8.92+/-0.09 in atrial myocardium and 8.79+/-0.04 in cerebral cortex of male rats, and 8.79+/-0.10 in uterine myometrium. Receptor densities in the cerebral cortex and atria were higher than in uterine myometrium, indicating that relaxin also has important roles in non-reproductive tissues. In male rats, treatment with 17beta-oestradiol (20 microg in 0.1 ml sesame oil s.c., 18-24 h) significantly decreased the density of relaxin receptors in atria and cerebral cortex. Identical treatment in female rats had no significant effect in atria and cerebral cortex, but it significantly increased the density of relaxin receptors in uterine myometrium. Relaxin binding was competitively displaced by porcine and rat native relaxins. Porcine native relaxin binds to the relaxin receptor in male rat atria (8.90+/-0.02), and cerebral cortex (8.90+/-0.03) and uterine myometrium (8.89+/-0.03) with affinities not significantly different from human gene 2 (B33) relaxin. Nevertheless, rat relaxin binds to the receptors with affinities (8.35+/-0.09 in atria, 8.22+/-0.07 in cerebral cortex and 8.48+/-0.06 in uterine myometrium) significantly less than human gene 2 (B33) and porcine relaxins. Quantitative receptor autoradiography is the method of choice for measurement of affinities and densities of relaxin receptor in atria, uterine myometrium and cerebral cortex. High densities were found in all these tissues. 17beta-oestradiol treatment produced complex effects where it increased the densities of relaxin receptors in uterus but decreased those in atria and cerebral cortex of the male rats, and had no effect on the atria and cerebral cortex of the female rats.

Solid-phase synthesis of ovine Leydig cell insulin-like peptide--a putative ovine relaxin?

The primary structure of ovine Leydig cell insulin-like peptide (Ley I-L) was recently deduced from the corresponding cDNA sequence. It consists of two peptide chains and three disulphide bonds in an arrangement similar to both relaxin and insulin. As in relaxin B-chain, an Arg-X-X-X-Arg sequence exists within the Ley I-L B-chain although it is located four residues towards the C-terminus from the corresponding position within relaxin. This sequence of amino acids is known to be essential for relaxin biological activity and its presence in Ley I-L suggested that the peptide might possess a relaxin-like function. Ovine Ley I-L was assembled by Fmoc-solid-phase synthesis of the separate chains followed by their combination in solution at high pH. The purity and identity of the chain-combined peptide was confirmed by chemical characterization including mass spectrometry. At physiological concentrations, the peptide was shown not to possess relaxin-like activity in the rat isolated atrial chronotropic and inotropic assay. This strongly suggests that Ley I-L is not a relaxin in the sheep. In order to explore further a possible structural relationship between Ley I-L and relaxin, we prepared a synthetic analogue of ovine Ley I-L containing a single replacement of B-chain residue 12, His, with Arg. This was found to possess significant relaxin-like chronotropic and inotropic activity demonstrating that the tertiary structure of Ley I-L is similar to that of relaxin and highlighting the key requirement for the five-residue sequence, Arg-X-X-X-Arg, to be present in position B12-16 for characteristic relaxin activity.

A case report on aggressive fibromatosis with bone involvement

Aggressive fibromatosis is a locally infiltrative fibroblastic tumour that arises from fascial planes of soft tissue but does not metastasize. It is known to invade muscle, subcutaneous tissue and neurovascular structures. However, bone involvement is very rare and there has been few reports of bone involvement. We present a case of a young man with aggressive fibromatosis of the right lower leg with fibula involvement.

Verrucous haemangioma--a case report

Verrucous haemangioma is an uncommon skin lesion which increases in size and also evolves in appearance with time. Early diagnosis is important so that surgical treatment can be instituted early for better cosmetic results. Its similarities and differences to angiokeratoma circumscriptum are also highlighted, and the importance of distinguishing the two in terms of management is discussed.

Comparison of relaxin receptors in rat isolated atria and uterus by use of synthetic and native relaxin analogues

1. The receptors for relaxin in the rat atria and uterus were investigated and compared by use of a series of synthetic and native relaxin analogues. The assays used were the positive chronotropic and inotropic effects in rat spontaneously beating, isolated right atrium and electrically driven left atrium and the relaxation of K+ precontracted uterine smooth muscle. 2. Relaxin analogues with an intact A- and B-chain were active in producing powerful chronotropic and inotropic effects in the rat isolated atria at nanomolar concentrations. Single-chain analogues and structural homologues of relaxin such as human insulin and sheep insulin-like growth factor I had no agonist action and did not antagonize the effect of the B29 form of human gene 2 relaxin. 3. Shortening the B-chain carboxyl terminal of human gene 1 (B2-29) relaxin to B2-26 reduced the activity of the peptide and removal of another 2 amino acid residues (B2-24) abolished the activity. This suggests that the B-chain length may be important for determination of the activity of relaxin. More detailed studies are needed to determine the effect of progressive amino acid removal on the structure and the bioactivity of relaxin. 4. Porcine prorelaxin was as active as porcine relaxin on a molar basis, suggesting that the presence of the intact C-peptide did not affect the binding of the prorelaxin to the receptor to produce functional responses. 5. Relaxin caused relaxation of uterine longitudinal and circular smooth muscle precontracted with 40 mM K+. The pEC50 values for human gene 2 and porcine relaxins were lower than those in the atrial assay, but rat relaxin had similar pEC50 values in both atrial and uterine assays. Rat relaxin was significantly less potent than either human gene 2 or porcine relaxin in the atrial assay, but in the uterine assay they were equipotent. The results suggest that the relaxin receptor or the signalling pathway in rat atria may differ from that in the uterus.

Uterine cancer--the KK Hospital experience

Kandang Kerbau Hospital saw 165 new cases of uterine cancers over the 4-year period from 1991 to 1994. The median age of presentation was 54.1 years and 10.9% of these cases occurred in those aged less than 40 years, unlike the corresponding figures of 61 years and less than 5%, respectively, which are often quoted for endometrial cancers in standard textbooks. Endometrioid adenocarcinoma was the commonest type of uterine cancer seen in our population (75.2%) as in other series. However, we had fewer cases of adenoacanthoma (1.4%) and adenosquamous carcinoma (1.4%) but more cases of uterine sarcoma (11.5%) than is usually reported. 6.7% of our patients had papillary serous adenocarcinoma and 3.0% had clear cell carcinoma. These 2 sub-types are associated with poorer prognosis and there is a need to increase awareness of their existence in our local population as their management differs from that for the usual endometrioid adenocarcinoma. We had fewer patients with stage I disease (53.3%) but more patients with stage III disease (22.4%). This is most likely due to the use of surgico-pathological staging currently as opposed to the clinical staging used previously which led to the under-staging of a proportion of patients.

Is postnatal oral glucose tolerance testing necessary in all women with gestational diabetes

Currently, women with gestational diabetes mellitus have a repeat oral glucose tolerance test 6 weeks after delivery to identify those with persistent glucose intolerance. In this study, 298 women with gestational diabetes had a postnatal oral glucose tolerance test and of these, 23.2% had persistent glucose intolerance after delivery. The aim of this study was to determine if the antenatal oral glucose tolerance test results could be used to predict which patients would have persistent glucose intolerance after delivery. If only those with severely abnormal antenatal results had persistent disease, then those with only mildly abnormal antenatal results could be spared the postnatal oral glucose tolerance test. Using receiver operator characteristic curves, this study showed that the antenatal oral glucose tolerance test results could not be used to predict reliably which patients would continue to have abnormal glucose tolerance postnatally. Hence, postnatal oral glucose tolerance testing of all patients with gestational diabetes is still necessary as the detection of persistent glucose intolerance is important for the control of the diabetic condition so as to minimise long-term complications.

Impaired glucose tolerance in pregnancy--is it of consequence?

This study was done to determine if impaired glucose tolerance in pregnancy was associated with increased maternal and neonatal morbidity and if so, whether the increased morbidity was due to the confounding factors of increased maternal age and maternal obesity. It was a retrospective analysis to compare 944 women with impaired glucose tolerance (IGT) in pregnancy with 10,065 women without abnormal glucose tolerance. The incidence of impaired glucose tolerance in pregnancy was 8.6% in this study. Even when maternal age and obesity were excluded, the IGT group had significantly higher risks of labour induction (relative risk, RR, 1.15); Caesarean section (RR: overall 1.43, elective 1.72, emergency 1.31); Caesarean section for dystocia/no progress (RR 1.60); macrosomia (RR 1.69, 1.76, 1.61 for birth-weight > = 97th, 95th, 90th percentiles respectively) and shoulder dystocia (RR 2.84) when compared to the nondiabetics (NDM). The risks of hypertensive disease (RR 1.22) and Caesarean section for fetal distress/thick meconium-stained liquor (RR 1.53) were also higher in the IGT group but these increases were not statistically significant when maternal age and obesity were excluded. There was no significant difference in the rates of low Apgar scores at 1 and 5 minutes between the 2 groups.

beta-Adrenoceptor regulation in rat heart, lung and skin after chronic treatment with (--)-tertatolol or (--)-propranolol

1. The effect of long-term treatment with the beta-adrenoceptor antagonists (--)-tertatolol and (--)-propranolol was studied. Sprague-Dawley rats were treated with either (--)-tertatolol (50 micrograms kg-1 hr-1), (--)-propranolol (250 micrograms kg-1 hr-1) or vehicle (1 mM HCl) for 14 days with osmotic minipumps implanted subcutaneously. 2. The mean daily systolic blood pressure and heart rate of rats treated with either (--)-tertatolol (108 +/- 1 mmHg/330 +/- 3 bpm) or (--)-propranolol (103 +/- 1 mmHg/330 +/- 2 bpm) were lower than in the control (126 +/- 1 mmHg/405 +/- 3 bpm, P < 0.001, n = 8-10) indicating the effectiveness of drug delivery. 3. Autoradiographic studies in areas of heart, lung and skin showed that beta-adrenoceptor populations were not significantly affected by the drug treatment (all regions P > 0.05). Nevertheless, the receptor population in the homogenates of (--)-tertatolol treated lung were halved (194 +/- 28 fmol mg protein-1 compared with a control value of 388 +/- 54 fmol mg protein-1, P < 0.01, n = 6). 4. In the presence of CGP 20712A, the left atrial inotropic and right atrial chronotropic responsiveness to (--)-isoprenaline were hypersensitive in both (--)-tertatolol and (--)-propranolol-treated groups (P < 0.005, ANCOVA). 5. (--)-Propranolol treated left ventricular free wall had lower basal [3H]-forskolin binding to adenylate cyclase (14.45 +/- 1.20 fmol mg protein-1 compared with a control value of 18.91 +/- 0.78 fmol mg protein-1, P = 0.01, n = 6). (--)-Tertatolol treatment had no effect on the basal binding. In the presence of the G-protein activators NaF and Gpp(NH)p, the enhancement of [3H]-forskolin binding did not differ between control and the drug treated groups. 6. Chronic (--)-tertatolol or (--)-propranolol treatment therefore did not produce an increase in receptors in heart, lung or skin but the beta-adrenoceptor-mediated responses were enhanced. In addition, [3H]-forskolin binding did not increase suggesting that the hypersensitivity was not due to changes in the number of receptors or adenylate cyclase. Hypersensitivity following beta-adrenoreceptor antagonist administration may therefore involve enhanced coupling of receptors to G-proteins.

Using glucose tolerance test results to predict insulin requirement in women with gestational diabetes

This study was done to test the clinical impression that the result of the oral glucose tolerance test could be used to predict which patients with gestational diabetes did not need insulin therapy. If this was true, a full blood sugar profile assessment could be avoided in many of these women. The second analysis was to test the clinical impression that the fasting glucose level was the best predictor of insulin requirement in women with gestational diabetes. The results of the study showed that none of the 3 readings of the oral glucose tolerance test could be used to predict reliably which patients did not need insulin therapy. Hence, blood sugar profile assessment of all patients with gestational diabetes is still necessary. The receiver-operator characteristic curves also showed that the 2-hour postload glucose level during the 75 g load glucose tolerance test was a better predictor of insulin requirement than the fasting glucose level.

Second trimester colour Doppler imaging of the uterine artery: reproducibility of the resistance index

Second trimester assessment of uterine blood flow has been advocated as a predictor of subsequent adverse perinatal outcome. The reproducibility of uterine artery resistance index, as assessed using colour Doppler imaging, was investigated. Two observers, both of whom were experienced in colour Doppler assessment of uterine artery flow velocity waveforms, performed the measurements. One-way analysis of variance was used to evaluate intraobserver variability and the limits of agreement method was used to determine the 95% prediction interval for interobserver differences. The intraobserver standard deviation was small for both observers. The limits of agreement for interobserver differences were wide (-0.24, 0.16), similar in magnitude to those reported by other workers who assessed the uterine vessel using continuous wave Doppler. The poor reproducibility of the resistance index suggests that second trimester Doppler assessment of uterine artery flow velocity waveforms may be better described using other semiquantitative methods such as the presence or absence of a diastolic notch.

Incidence, timing, and management of biliary tract complications after orthotopic liver transplantation

Images

Gall bladder tumour, choledochal cyst and an anomalous pancreatico-biliary junction

This report highlights the association of a tumour in an acalculous gall bladder with an anomalous pancreatico-biliary junction (PBJ) and a type IVa choledochal cyst. Cholecystectomy and Rouxen-Y hepatico-jejunostomy (RHJ) was performed after division of the common bile duct (CBD) and excision of the dilated segment. The details of the case are presented and the role of an abnormal PBJ in gall bladder carcinogenesis is discussed.

Comparative antibody response to Salmonella antigens in genetically resistant and susceptible mice

The ELISA was used to titrate the antibody response in mice inoculated with salmonella antigens. The genetically resistant A/J and susceptible C57BL/6J mice were either infected with the virulent or the avirulent Salmonella typhimurium. Alternatively, they were inoculated either once or twice with the heat-killed salmonella vaccine. No appreciable difference could be detected in the relative ability of these two strains of mice to produce antibodies against the lipopolysaccharide antigens of this pathogen under these four conditions.

Risk factors and a risk scoring system for the prediction of malignancy in ovarian cysts

A retrospective study was carried out on 396 patients who presented with ovarian masses. Sixty five (16%) patients were found to have ovarian malignancy while the rest either had benign ovarian tumours (n = 159), endometriotic cysts (n = 130), physiological cysts (n = 20) or inflammatory masses (n = 7). The relative risk for ovarian malignancy among these patients increased significantly (p < 0.001) after the age of 40 years. The presence of ascites, abdominal distension, urinary complaints and loss of appetite and weight were significant individual risk factors for malignancy. Ultrasound image of a complex cyst is also associated with increased risk of malignancy in an ovarian mass. None of the individual risk factors was discriminatory between a benign and malignant cyst. However, these factors can be combined to form a 20-point risk scoring system. The risk of malignancy in an ovarian cyst increased with increasing scores. In this study, the median scores were 3 for benign cyst, 7 for borderline malignancy and 12 for malignant cysts. Using a total score of 7 as a cut off point, one can detect 75% of malignant cysts with a specificity of 84.1%, a positive predictive value of 47.5% and a negative predictive value of 94.6%. It is concluded that the majority of malignant ovarian cysts can be identified preoperatively to allow arrangement and planning of an optimal surgery.

Outcome prediction in early management of severe head injury: an experience in Malaysia

The outcome of 109 patients with severe head injury was studied in relation to clinical and computed tomographic (CT) criteria on admission, after resuscitation. Age, Glasgow Coma Score (GCS) and state of pupils strongly correlated with outcome. The presence of hypothalamic disturbances, hypoxia and hypotension were associated with an adverse outcome. The CT indicators associated with poor outcome were perimesencephalic cistern (PMC) obliteration, subarachnoid haemorrhage, diffuse axonal injury and acute subdural haematoma. The prognostic value of midline shift and mass effect were influenced by concomitant presence of diffuse brain injury. For the subset of patients aged < 20 years, with GCS 6-8 and patent PMC (n = 21), 71.4% correct predictions were made for a good outcome. For the subset of patients aged > 20 years, with GCS 3-5 and partial or complete obliteration of PMC (n = 28), 89.3% correct predictions were made for a poor outcome.

In vitro evaluation of 6-thioguanine and alpha-interferon as a therapeutic combination in HL-60 and natural killer cells

The effect of 6-thioguanine (6-TG) and alpha-interferon (IFN-alpha) was evaluated in vitro to determine their effectiveness in combination on the therapeutically relevant events of: HL-60 cell cytotoxicity, HL-60 cell differentiation, and natural killer (NK)-cell mediated cytotoxicity. 6-TG was toxic to HL-60 cells (ID50 = 0.6 microM; 24-h exposure) while IFN-alpha (up to 1000 IU/ml) had minimal cytotoxic activity. Sequence-dependent activity was observed, inasmuch as the IFN-alpha pretreatment sequence was antagonistic, while the other schedules were additive or, possibly, synergistic. The combination of 0.5 microM 6-TG and 100 IU/ml IFN-alpha produced the same level of HL-60 cell differentiation as each agent alone, suggesting no benefit from the combination on this process. The effect of 6-TG and IFN-alpha on NK cell-mediated cytotoxicity was found to be sequence dependent. NK cell activity was markedly stimulated by IFN-alpha, whereas 6-TG alone seemed to have no direct effect. However, when the NK cells were pretreated with 100 IU/ml IFN-alpha followed by 10 microM 6-TG, the IFN-alpha-enhanced activity of NK cells was ablated. These results suggest that the immunosuppressive activity of 6-TG may be related to the acute inhibition of cytokine activation. Our results suggest that 6-TG and IFN-alpha have considerable interactions, which are sequence dependent. The optimal sequence for potential therapeutic application of these anticancer agents appears to be 6-TG pretreatment followed by IFN-alpha.

Correlation between ribosomal RNA production and RNA-directed fluoropyrimidine cytotoxicity

The relationship between cytotoxicity and fluoropyrimidine effects on the production of mature cytoplasmic 28S and 18S ribosomal RNA was studied in S-180 cells for the fluoropyrimidines: 5-fluorouracil (FUra), 5-fluorouridine (FUrd), 5-fluorodeoxyuridine (FdUrd), and 5'-deoxy-5-fluorouridine (5'-dFUrd). After a 6-hr drug exposure, the total cytotoxicity in the absence of added thymidine (dThd) was determined by soft-agar cloning and resulted in LC90 (lethal concentration to 90% of cells) values of 0.6 microM FdUrd, 0.7 microM FUrd, 5.3 microM FUra and 93 microM 5'-dFUrd. The RNA-directed (dThd-nonreversible) cytotoxicity was assessed by cloning the cells in the presence of 10 microM dThd. This resulted in an altered order of potency and increased LC90 values to 5.5 microM FUrd, 20 microM FUra, 265 microM FdUrd and 870 microM 5'-dFUrd. The production of mature cytoplasmic rRNA was determined by measuring the amount of [3H]cytidine incorporated into the 28S and 18S rANA species following their separation by agarose gel electrophoresis, compared with the level of [3H]cytidine incorporated into the nuclear rRNA. When all four fluoropyrimidines were compared together, the degree of inhibition of cytoplasmic rRNA production was poorly predictive of the total cytotoxicity in the absence of dThd (correlation coefficient, r = 0.77). FdUrd, in particular, had a very minor effect on rRNA production even at very toxic drug concentrations. When toxicity was assessed in the presence of dThd, however, there was a strong and significant correlation between rRNA production and RNA-directed cytotoxicity (r = 0.95, P less than 0.001), for all the fluoropyrimidines tested, including FdUrd. Thus, when the inhibition of thymidylate formation was eliminated as a site of drug action and only RNA-directed cytotoxicity was assessed, the impaired production of cytoplasmic rRNA was strongly associated with cytotoxicity. These results demonstrate that the inhibition of mature cytoplasmic rRNA production may be an important common mechanism of RNA-directed cytotoxicity for all the fluoropyrimidines, and not limited to FUrd or FUra.