Uncovering novel mutational signatures by de novo extraction with SigProfilerExtractor

Mutational signature analysis is commonly performed in cancer genomic studies. Here, we present SigProfilerExtractor, an automated tool for de novo extraction of mutational signatures, and benchmark it against another 13 bioinformatics tools by using 34 scenarios encompassing 2,500 simulated signatures found in 60,000 synthetic genomes and 20,000 synthetic exomes. For simulations with 5% noise, reflecting high-quality datasets, SigProfilerExtractor outperforms other approaches by elucidating between 20% and 50% more true-positive signatures while yielding 5-fold less false-positive signatures. Applying SigProfilerExtractor to 4,643 whole-genome- and 19,184 whole-exome-sequenced cancers reveals four novel signatures. Two of the signatures are confirmed in independent cohorts, and one of these signatures is associated with tobacco smoking. In summary, this report provides a reference tool for analysis of mutational signatures, a comprehensive benchmarking of bioinformatics tools for extracting signatures, and several novel mutational signatures, including one putatively attributed to direct tobacco smoking mutagenesis in bladder tissues.

294 Implementation of Colorectal Robotic Assisted Surgical Programme During a Global Pandemic: Collaboration Between Territorial and National Waiting Times Centre

Introduction

Golden Jubilee National Hospital (GJNH) established a thoracic Robotic Assisted Surgical (RAS) programme in 2018. In March 2021, GJNH invested in a new elective colorectal service and in response to the Scottish Government robotic investment established a collaboration with a territorial health board to host their robot and start a RAS colorectal programme. We provide an overview of barriers and facilitators leading to establishing this new collaboration.

Method

An observational review of RAS training timeline. Demographics, surgical operations, and hospital length of stay were documented. Surgeons, perioperative team, management, and industry (Intuitive) were interviewed to provide insights into implementation and training.

Results

Boards approved RAS business case in April 2021, robot on-site with GJNH governance approval in May. First cohort of colorectal surgeons completed proctored training July 2021. To date, 17 RAS resections performed (mean age 64, 9 males: 8 female). Mean length of stay 4.65 days. No anastomotic leaks and no mortality reported. Interviews revealed key facilitators: advantage of having an established RAS perioperative team and building on pre-existing industry links; developing and strengthening collaborative working between different health boards and surgeons. Barriers included: education of all team members to ensure patient safety for new specialty; multisite collaborative working.

Conclusions

This work provides a template model for future RAS collaborations between different sites and health boards. Collaborative working in a green-hospital setting may improve equity of access for patients whilst future-proofing surgery against further waves of the pandemic.

Comparison of MRI, MRA, and DSA for Detection of Cerebral Arteriovenous Malformations in Hereditary Hemorrhagic Telangiectasia

BACKGROUND AND PURPOSE

Patients with hereditary hemorrhagic telangiectasia (HHT) have a high prevalence of brain vascular malformations, putting them at risk for brain hemorrhage and other complications. Our aim was to evaluate the relative utility of MR imaging and MRA compared with DSA in detecting cerebral AVMs in the HHT population.

MATERIALS AND METHODS

Of 343 consecutive patients evaluated at the University of California, San Francisco HTT Center of Excellence, 63 met the study inclusion criteria: definite or probable hereditary hemorrhagic telangiectasia defined by meeting at least 2 Curacao criteria or positive genetic testing, as well as having at least 1 brain MR imaging and 1 DSA. MRIs were retrospectively reviewed, and the number of AVMs identified was compared with the number of AVMs identified on DSA.

RESULTS

Of 63 patients, 45 (71%) had AVMs on DSA with a total of 92 AVMs identified. Of those, 24 (26%) were seen only on DSA; 68 (74%), on both DSA and MR imaging; and 5 additional lesions were seen only on MR imaging. Of the 92 lesions confirmed on DSA, 49 (53.3%) were seen on the 3D-T1 postgadolinium sequence, 52 (56.5%) were seen on the 2D-T1 postgadolinium sequence, 35 (38.0%) were seen on the SWI sequence, 24 (26.1%) were seen on T2 sequence, and 25 (27.2%) were seen on MRA. The sensitivity and specificity of MR imaging as a whole in detecting AVMs then confirmed on DSA were 80.0% and 94.4%, respectively, and the positive and negative predictive values were 97.3% and 65.4%, respectively.

CONCLUSIONS

This study reinforces the use of MR imaging as a primary screening tool for cerebral AVMs in patients with hereditary hemorrhagic telangiectasia and suggests that 3D-T1 postgadolinium and 2D-T1 postgadolinium performed at 3T are the highest yield sequences.

Prognostic research and its potential role in modern gynaecology: a call for more prognostic research in urogynaecology

Over the last 30 years, many researchers have focussed on therapeutic and aetiological studies. Randomised controlled trials (RCT) are considered the 'gold standard' in research circles ( Ward et al. 2004 ). Prognostic research has been neglected probably due to a combination of a lack of perception of its importance and also a failure to produce good quality trials. The word 'prognosis' means the ability to foresee or predict an outcome or an event. Prognostic research in medicine is the ability to predict the likelihood of outcomes from a number of clinical variables. There are two main forms of prognostic research. One form identifies the prognostic value of a single risk factor (e.g. a tumour marker). The second one focuses on the development of a model based on multiple variables and is called multivariable prognostic modelling. The planning and powering of prognostic studies is managed differently from traditional randomised controlled trials.

Studies of TBX4 and chromosome 17q23.1q23.2: an uncommon cause of nonsyndromic clubfoot

Clubfoot is a common birth defect characterized by inward posturing and rigid downward displacement of one or both feet. The etiology of syndromic forms of clubfoot is varied and the causes of isolated clubfoot are not well understood. A microduplication of 2.2 Mb on chromosome 17q23.1q23.2 which includes T-box 4 (TBX4), a hindlimb-specific gene, and 16 other genes was recently identified in 3 of 66 families reported as nonsyndromic clubfoot, but additional non-foot malformations place them in the syndromic clubfoot category. Our study assesses whether variation in or around TBX4 contributes to nonsyndromic clubfoot. To determine whether this microduplication was a common cause of nonsyndromic clubfoot, 605 probands (from 148 multiplex and 457 simplex families) with nonsyndromic clubfoot were evaluated by copy number and oligonucleotide array CGH testing modalities. Only one multiplex family (0.68%) that had 16 with clubfoot and 9 with other foot anomalies, had a 350 kb microduplication, which included the complete duplication of TBX4 and NACA2 and partial duplication of BRIP1. The microduplication was transmitted in an autosomal dominant pattern and all with the microduplication had a range of phenotypes from short wide feet and toes to bilateral clubfoot. Minimal evidence was found for an association between TBX4 and clubfoot and no pathogenic sequence variants were identified in the two known TBX4 hindlimb enhancer elements. Altogether, these results demonstrate that variation in and around the TBX4 gene and the 17q23.1q23.2 microduplication are not a frequent cause of this common orthopedic birth defect and narrows the 17q23.1q23.2 nonsyndromic clubfoot-associated region.

Effect of tension-free vaginal tape position on the resolution of irritative bladder symptoms in women with mixed incontinence

The aim of this study was to determine whether the position of the tension-free vaginal tape (TVT) has an effect on the resolution of irritative symptoms in women undergoing the TVT operation. Initial audit suggested that more distally placed tapes were more likely to result in the resolution of irritative symptoms. An appropriately powered study was designed to test this theory. Seventy-seven women with urodynamic evidence of detrusor overactivity and urodynamic stress incontinence underwent a transperineal ultrasound scan to ascertain the position of the tape after a TVT. The tape was categorised as proximal, middle or distal urethra. The resolution of irritative symptoms was assessed compared to the TVT position. Forty-five women had distal tapes, 30 had mid-urethral tapes and two had proximal tapes. Women with the TVT placed on the distal urethra were no more likely to experience resolution of their irritative symptoms than women with tapes on the mid-urethra (p > 0.05). Placement of the TVT on any one part of the urethra is not more likely to result in resolution of irritative bladder symptoms.

The value of cystoscopy and bladder biopsy taken at the time of tension-free vaginal tape insertion

The primary aim of this study was to determine if a cystoscopy performed at the time of a tension-free vaginal tape (TVT) insertion is useful in finding unexpected pathology. A secondary outcome measure was to assess whether a bladder biopsy and cystoscopy performed during the TVT operation provide useful information about the outcome of surgery. The findings in 100 consecutive women were reviewed. A total of 42 women demonstrated mixed detrusor overactivity (DO) and urodynamic stress incontinence (USI); 32 women had abnormal biopsies. Women with DO were no more likely to have abnormal bladder biopsies than women without DO (p > 0.05). An abnormal bladder biopsy or cystoscopy failed to predict postoperative irritable symptoms (p > 0.05). The presence of preoperative DO correctly predicted postoperative irritable symptoms (p < 0.01). Cystoscopic abnormalities were noted in 14 women including one carcinoma, and one case of dysplasia was discovered on biopsy. In five women, the cystoscopy showed a bladder perforation. Cystoscopy should be performed in all women undergoing continence procedures.

Tolerability and efficacy of duloxetine in a nontrial situation

OBJECTIVE

To assess the tolerability and efficacy of duloxetine in a nontrial situation.

DESIGN

Prospective observational study.

SETTING

Urogynaecology Unit, District General Hospital, UK.

POPULATION

Two hundred and twenty-two women with a diagnosis of urodynamic stress incontinence (USI) or mixed USI and detrusor overactivity (DOA) took duloxetine for 4 weeks.

METHODS

The results of therapy were assessed with a Patient Global Impression of Improvement (PGI-I) questionnaire. One hundred and forty-eight (67%) women were initially treated with 40 mg twice a day, 67 (30%) women were treated with an escalating dose initially at 20 mg twice a day increasing to 40 mg twice a day after 2 weeks and seven (3%) women were started on a dose of 20 mg twice a day which they continued.

MAIN OUTCOME MEASURES

Discontinuation rates and PGI-I scores.

RESULTS

Overall 146/222 (66%) women discontinued therapy due to adverse effects or lack of efficacy. Significantly more women starting on the 40 mg twice a day dose stopped due to adverse effects when compared with the escalating dose (P < 0.025). Of the women who tolerated therapy, 80 out of 120 (67%) had a PGI-I score indicating an improvement. However, the overall rate of improvement was 37%. PGI-I scores and discontinuation rates were not significantly different between the group with USI and the group with mixed USI and DOA (P > 0.05).

CONCLUSION

In a nontrial situation duloxetine is poorly tolerated. Introducing an escalating dose may improve tolerability. A similar number of women with USI and mixed incontinence had a PGI-I score indicating improvement.

Pathophysiology and Clinical Aspects of Urinary Lithiasis

Urine is a complex balanced solution containing dissociated and non-dissociated solutes. Any variation in urine saturation grade (number of crystals dissolved in a volume of urine), urinary pH and the concentration of crystallization inhibitors can break the normal existing balance and lead to urolithiasis. In the present article we analyze the principal mechanisms (absorptive, renal, resorptive) of hypercalciuria. It will be also shown how heredity directly influences the clinical aspects of cystine, xanthine and oxalate lithiasis and how diet, in association with metabolic disorders, interferes in uric acid and oxalate stone formation. Finally, we report on the roles of urinary tract malformations, urinary tract infections and drugs in the clinical characterization of urolithiasis.

ESWL Prediction of Outcome and Failure Prevention

Based on our own experiences and a review of the recent literature, this article evaluates recent developments in predicting outcomes and failures of shockwave lithotripsy when treating patients with urinary tract stones. After a detailed MEDLINE research, the authors identified several variables that influence and predict extracorporeal shockwave lithotripsy (ESWL) success. These variables may be categorized as stone variables, patient variables and operator variables. Only multivariate analysis on a large number of homogenous patients may offer an objective evaluation of the factors conditioning ESWL outcome.

New developments in the treatment of urinary incontinence

Urinary incontinence is a common and distressing condition. The two main types of incontinence in the developed world are urodynamic stress incontinence and detrusor overactivity. Recent advances have focussed on the development of a drug for stress incontinence and on the production of newer more M3 specific anticholinergics. Duloxetine, a relatively balanced and potent serotonin noradrenaline reuptake inhibitor, is the first drug to be licensed for stress incontinence. Until recently, the pharmacological treatment options for stress urinary incontinence (SUI) have been limited to the off-the label use of several medications including oestrogens, alfa adrenergic receptor agonists, beta adrenergic receptor antagonists, tricyclic antidepressants and anticholinergics. However, these medications have questionable efficacy which may be associated with adverse effects. Randomised trials have shown duloxetine to be effective at reducing incontinence episode frequency and improving quality of life scores. Hence medical management has now become a more realistic option for treatment of patients with sui. Recently newer more M3 receptor selective anticholinergics have come on to the market. Their increased bladder receptor selectivity implies that they have improved efficacy with a lower side effect profile. Both solifenacin and more recently darifenacin have been marketed and have the above described properties. The oxybutynin patch is now also available adding a new route of delivery. Because it is absorbed transdermally, its manufacturers claim it also has a better efficacy/tolerability ratio then conventional oxybutynin. This review article gives a detailed description of these new pharmacologic developments.

Microwave-Induced Hyperthermia and Cytostatic Agent for Superficial Bladder Cancer

The efficacy and local toxicity of the intravesical combination of microwave-induced hyperthermia with a cytostatic agent in patients affected by superficial bladder cancer is presented. Between 1994 and 2002, two studies were performed on ablative and adjuvant intravesical thermo-chemotherapy. The ablative study demonstrated complete tumor eradication in 88% of patients who should have undergone cystectomy due to diffuse multiple papillary tumors non-responsive TUR and intravescical adjuvant therapy. In a randomized study, comparing adjuvant thermo-chemotherapy vs. standard chemotherapy with mitomycin C, recurrence-free survival analysis at 24 months revealed a significant difference in favor of thermo-chemotherapy. Our preliminary experience confirmed that local side effects, mainly cystitis, suprapubic pain and thermal reaction of the posterior bladder wall, were transitory and did not require treatment interruption.

New developments in the management of urinary incontinence

Urinary incontinence is a common and distressing condition known to adversely affect quality of life. In this article the authors aim to highlight developments in the methods of classification, investigation and the treatment of incontinence. It gives a detailed description of the newer drugs and their mode of action, that have recently come on to the market. These include duloxetine for the treatment of stress incontinence and the newer M3 selective antagonists. It also describes the latest surgical procedures, for example the newer slings and injectables used to treat stress incontinence. They are compared with the standard forms of treatment used and the evidence in favour and against these have been given.

The Prognostic Value of P53 in Predicting of Bladder Carcinoma

The prognostic value of p53 in predicting recurrence and progression of superficial transitional cell carcinoma of the bladder (TCCB) is still uncertain.

Materials and methods

P53 expression was retrospectively assessed in 160 patients. At a median follow-up of 45 months, (up to years) 84 patients (53%) recurred and 13 (8%) progressed. Adjuvant intravesical chemotherapy after TUR was adopted in 51 patients (32%). The correlations between p53 and G-grade, T-category, risk of recurrence and progression, and intravesical chemotherapy were investigated. Similarly, the correlations between variations in grade and stage at recurrence and modifications in p53 expression were also studied.

Results

Seventy-nine patients (49%) were negative for p53. P53 was expressed in 84% of G3 tumors and in 65% of T1 lesions. A significant correlation between p53 expression and G-grade (p<0.0001) and T-category (p<0.0001) of the tumor was found. Eight-four patients (53%) recurred and 13 (8%) progressed. No correlation was found with recurrence and response to intravesical chemotherapy. P53 expression resulted correlated to progression in T1 tumors (although was not independent from G-grade).

Conclusion

According to our experience, p53 expression is not independent from grade and stage of superficial TCCB. A significant correlation between p53 expression and progression, not independent from G-grade, was detected only in T1 tumors.

Impact of video colonoscopy on stage and outcome of patients with symptomatic colorectal cancer

BACKGROUND

Double-contrast barium enema still is regarded by many as the investigation of choice for patients with large bowel symptoms. The aim of this study was to compare the stage and outcome of patients with colorectal cancer diagnosed by video colonoscopy (VC) and barium enema (BE) in a single institution.

METHODS

Between July 1997 and December 2001, data were gathered prospectively in a series of 489 patients presenting consecutively with symptomatic colorectal cancer. Selection of patients for either VC or BE investigation was made by the clinician who examined the patient in the clinic. Of the 489 patients, 82 were excluded because they presented acutely or other methods were used for the diagnosis.

RESULTS

A diagnosis of colorectal cancer was determined by VC for 292 patients and by BE for 115 patients. The patients in both groups were similar in terms of age, gender, and site of disease. Stage 1 disease (T1/2NO) was diagnosed for 87 (29.8%) patients in the VC group, as compared with 10 (8.7%) in the BE group (p < 0.0001). Early colorectal cancer (T1) was diagnosed for 43 patients in the VC group as compared to 1 patient in the BE group (p < 0.0001). During a median follow-up period of 33 months, 8.2% of the patients in the VC group had experienced recurrence after curative resection, as compared with 17.4% of the patients in the BE group p = 0.018). Freedom from disease (p = 0.02) and overall survival (p = 0.03) were significantly increased in the VC group.

CONCLUSIONS

Videocolonoscopy used as the investigation of choice for patients with large bowel symptoms detects colorectal cancer at an earlier stage and has a significant impact on the outcome for this condition.

Randomized clinical trial comparing consultant-led or open access investigation for large bowel symptoms

BACKGROUND

Referral of patients with large bowel symptoms is common and increasing. Currently most of these referrals are assessed at an outpatient clinic to determine the need and priority for investigation.

METHODS

Over 21 months, 1131 patients referred by the general practitioner with large bowel symptoms were randomized. Patients in the consultant-led group were assessed by surgeons with a colorectal interest while those in the open access group underwent colonoscopy if they were 55 years or older and flexible sigmoidoscopy if younger.

RESULTS

The most common symptom among referred patients was rectal bleeding (69.1 per cent) followed by change in bowel habit (48.8 per cent) and abdominal pain (32.3 per cent). There was a significant trend (P < 0.001) for patients in the consultant-led to have more investigations, and more patients in this group had no investigations (P < 0.001). Despite this, the percentage of patients with colonic or other pathology diagnosed was the same in both groups, 63.6 per cent in the consultant-led group compared with 61.8 per cent in the open access group (P = 0.558). Likewise the percentage of patients with cancer or other significant pathology was similar in both groups (13.9 versus 15.4 per cent; P = 0.532). The mean(s.d.) time to diagnose cancer or other significant pathology was 55.1(39.2) days in the consultant-led group compared with 57.4(33.6) days in the open access group (P = 0.514). The cost per patient was almost pound 105 more for patients in the consultant-led group.

CONCLUSION

Patients referred by the general practitioner with large bowel symptoms should go directly to a properly managed and staffed open access large bowel investigation unit. This would enable most patients to have their investigations completed at one hospital attendance.

The application of databases and PCR in the cloning of glycosidase genes from the protozoan Tritrichomonas foetus

Conserved sequence amplification (CSA) has been used to obtain sequence data for two glycosidase genes from the primitive eukaryote Tritrichomonas foetus. Few genes have been cloned from this organism, and there is little information concerning protein sequence. CSA is reliant on the use of database searches to identify short sequences of 3-9 amino acids conserved within a protein across a wide range of species. PCR primers are then constructed based on this sequence data and the DNA is amplified and sequenced. In the case of the beta-galactosidase gene, N-terminal amino acid sequence data were used to construct a primer that replaced the upstream primer to ensure the amplified product was related to beta-D-galactosidase. CSA was also applied to the gene encoding the enzyme beta-N-acetyl-D-glucosaminidase from T. foetus, but in this case a segment of DNA was amplified, which, if correct, should contain a third conserved motif. The products of the CSA were sequenced, and the data obtained were compared to data in the SwissProt database. The results obtained suggest that this approach is useful for the cloning of genes to obtain novel sequence data from organisms where little genetic information is available.

Purification and partial characterization of beta-galactosidase from Tritrichomonas foetus

The work presented in this paper describes the purification and properties of a beta-galactosidase from the protozoan Tritrichomonas foetus. An inexpensive and straightforward method for extraction of the enzyme involving ammonium sulphate precipitation, ion exchange and affinity chromatography resulted in a high level of purification. After purification beta-N-acetylglucosaminidase was the only enzyme present as a contaminant at a significant level. The beta-galactosidase isolated had a pH optimum of 5.8. The Km determined at pH 5.8 was found to be 2.2 mM. Interesting results were obtained when studies were carried out to determine the effect of various metal ions on enzyme activity. Of the metal ions used in this study only manganese ions were found to activate the enzyme. This seems to be a characteristic of trichomonad enzymes, as N-acetyl-beta-glucosaminidase, alpha-galactosidase and N-acetyl-alpha-galactosaminidase are also activated by manganese ions. The strongest inhibition was recorded with lead and to a lesser extent by zinc. The result with lead is not unexpected as the heavy metal is known to cause irreversible inhibition by binding to the amino-acid backbone of the enzyme. The result with zinc is interesting as high levels of zinc are present and trichomonads are known to be apathogenic in semen. The purified beta-galactosidase was found to have the capacity to hydrolyse lactose (Gal beta1-4 Glc), lacto-N-biose 1 (Gal beta1-3 GlcNAc) and N-acetyllactosamine (Gal beta1-4 GlcNAc). When the enzyme was applied to a non-denaturing polyacrylamide gel a single band was observed when stained with Coomassie brilliant blue. This band coincided with that obtained when the gel was stained with p-nitrophenyl beta-galactopyranoside. When the same gel was incubated with p-nitrophenyl N-acetyl beta-glucopyranoside a band was detected which did not coincide with that of beta-galactosidase. Since the beta-N-acetylglucosaminidase enzyme does not move to the same position on a non-denaturing gel as the beta-galactosidase, we will use this technique to isolate the latter enzyme and determine the N-terminal sequence as a prelude to cloning and further study of the gene.

[Conservative treatment of dysplastic multicystic kidney]

BACKGROUND

Recent developments regarding the conservative management of multicystic dysplastic kidney disease (MDKD) have shown a reduction in the well-established practice of elective surgical treatment. It has been seen that in the majority of cases the evolution of MDKD is either partial or complete atrophy. The incidence of complications due to MDKD is very low. The aim was to study the ultrasound changes of MDKD in a group of patients from 1990, since this date the elective surgical procedure had been eliminated.

MATERIALS AND METHODS

This group consisted of 16 patients. The diagnosis in each patient was confirmed by ultrasound and isotopic examinations. Other investigations were performed where there was a suspect of associated contralateral renal abnormalities or when a urinary tract infection occurred.

RESULTS

Ultrasound follow-up revealed: no enlargement whatsoever in the kidney size in any patient; in 10 patients a reduction in the size of the MDK; in 3 patients a complete atrophy of MDK; in 3 patients there was no change at all. Five patients were found to have contralateral renal abnormalities. Compensatory hypertrophy of the contralateral kidney was present in all patients. No complications occurred. A nephrectomy was performed only in one patient aged 6 due to the express wishes of his parents.

CONCLUSIONS

The results agree with recently published literature that routine surgical removal of the MDK is unnecessary.

Patterns urodinamici in pazienti con prostatodinia

The Authors report their experience on 24 patients with prostatodynia. The Adynamic alterations, which occur in most cases, show the usefulness of cystomanometry and pressure-flow study for providing a better nosological picture and therapeutic management.

The effect of hypnotically elicited testimony on jurors' judgments of guilt and innocence

Survey data from several countries indicate that many people believe that hypnosis may increase the accuracy of an eyewitness's memory; most experimental research, however, suggests that this belief is inaccurate. This study examined whether the belief could influence judgments of guilt and innocence in a simulated criminal trial. The results indicated that British undergraduates were more likely to find a male defendant guilty when told that the testimony against him had been elicited under hypnosis. Results concerning a nonhypnotic memory facilitation technique were found to be inconclusive, and the salience of hypnotically elicited testimony was ruled out as a contributory element.

The flexible cystoscope

We have been using the flexible cystoscope since 1987. Detailed information is given concerning the technique of flexible cystoscopy, its indications, advantages and disadvantages. A comparison is made with the results obtained using the rigid cystoscope in an initial series of 100 patients, yielding false negative results in only 8% of cases during the learning period. The flexible scope can be successfully employed for Neodymium YAG laser coagulation of superficial bladder tumours. The conclusion is reached that once the urologist has learned how to use it, he will consider the flexible cystoscope as a fundamental tool in his diagnostic armamentarium and false negative results will decrease almost to zero, especially if additional investigations, namely cytology, are routinely adopted.

Phase II rehabilitation of the temporomandibular joint dysfunction patient

Treatment of pain and dysfunction of the craniomandibular apparatus commonly follows one of two courses, not necessarily independent of each other. In many patients, treatment involves both appliance and non-appliance modalities. A thorough and careful diagnostic evaluation of the patient will help the dentist to select the proper modality of treatment. Following successful Phase I therapy, the patient is now prepared for Phase II therapy, a more definitive treatment stage. The purpose of this article is to provide the reader with the rationale and principles underlying the stabilization and rehabilitation direction of Phase II therapy, emphasizing the prosthodontic and orthodontic perspectives.

Repeat radiation synovectomy with dysprosium 165-ferric hydroxide macroaggregates in rheumatoid knees unresponsive to initial injection

Because of failure to fully respond to an initial intraarticular injection of dysprosium 165-ferric hydroxide macroaggregates, 17 patients with seropositive rheumatoid arthritis underwent repeat radiation synovectomy using this agent. Of the 13 patients who were evaluated 1 year later, 54% (7 knees) had good results, 31% (4 knees) had fair results, and 15% (2 knees) had poor results. The initial lack of significant benefit from radiation synovectomy did not appear to preclude a favorable response to a second injection.

Hepatic granulomas

There are several causes of hepatic granulomas, infective and non-infective. Modern technology, including monoclonal antibody techniques and histochemistry, has shed light on the morphology of the sarcoid granuloma. There are numerous causes of hepatic granulomas, both infective and non-infective. The causes are listed and a clinico-pathological plan of management outlined.

Acipimox in the treatment of patients with hyperlipidaemia: a double blind trial

Fifty-two patients with Fredrickson Type IIb or Type IV hyperlipidaemia, in whom diet had not achieved satisfactory lipid levels, completed a double blind randomised study of acipimox versus placebo. The patients were given acipimox, 250 mg three times daily or placebo for a three month period, and plasma lipids and glucose were monitored. The patients receiving acipimox showed a fall in the mean concentration of plasma triglyceride compared to placebo (0.74 mmol/l) and this was most marked in patients whose initial plasma triglyceride levels were greater than 3 mmol/l (1.0 mmol/l, confidence limits 0.18, 1.82). Acipimox was well tolerated, and could be a useful addition to the drugs available for the treatment of patients with hypertriglyceridaemia.

Alimentary tract granulomas

Sarcoidosis rarely affects the alimentary tract and is usually asymptomatic. However, sarcoid granulomas are commonly found as a reaction to a local cause or as a feature of other systemic disease. Thus, the differential diagnosis of alimentary tract granulomas is wide. Before accepting a diagnosis of sarcoidosis of the alimentary tract, it is important to exclude its many mimics.

A DNA polymorphism adjacent to the human apolipoprotein CII gene

We have used a cDNA clone for human apolipoprotein CII (apo CII) to detect a common DNA polymorphism with the enzyme TaqI. This polymorphism is probably caused by a single base change approximately 2000 base-pairs from the 3' end of the structural gene. In the normal population (n = 90) the frequency of the less common allele is approximately 0.44. No significant differences were observed in the allele frequency in individuals with type IIa, IIb, III, IV and V lipoprotein patterns. There does not seem to be any population association between the TaqI polymorphism and factors that predispose an individual to hyperlipidaemia.