Complement factor I: Regulatory nexus, driver of immunopathology, and therapeutic

Complement factor I (FI) is the nexus for classical, lectin and alternative pathway complement regulation. FI is an 88 kDa plasma protein that circulates in an inactive configuration until it forms a trimolecular complex with its cofactor and substrate whereupon a structural reorganization allows the catalytic triad to cleave its substrates, C3b and C4b. In keeping with its role as the master complement regulatory enzyme, deficiency has been linked to immunopathology. In the setting of complete FI deficiency, a consumptive C3 deficiency results in recurrent infections with encapsulated microorganisms. Aseptic cerebral inflammation and vasculitic presentations are also less commonly observed. Heterozygous mutations in the factor I gene (CFI) have been demonstrated to be enriched in atypical haemolytic uraemic syndrome, albeit with a very low penetrance. Haploinsufficiency of CFI has also been associated with decreased retinal thickness and is a strong risk factor for the development of age-related macular degeneration. Supplementation of FI using plasma purified or recombinant protein has long been postulated, however, technical difficulties prevented progression into clinical trials. It is only using gene therapy that CFI supplementation has reached the clinic with GT005 in phase I/II clinical trials for geographic atrophy.

The rare C9 P167S risk variant for age-related macular degeneration increases polymerization of the terminal component of the complement cascade

Age-related macular degeneration (AMD) is a complex neurodegenerative eye disease with behavioral and genetic etiology and is the leading cause of irreversible vision loss among elderly Caucasians. Functionally significant genetic variants in the alternative pathway of complement have been strongly linked to disease. More recently, a rare variant in the terminal pathway of complement has been associated with increased risk, Complement component 9 (C9) P167S. To assess the functional consequence of this variant, C9 levels were measured in two independent cohorts of AMD patients. In both cohorts, it was demonstrated that the P167S variant was associated with low C9 plasma levels. Further analysis showed that patients with advanced AMD had elevated sC5b-9 compared to those with non-advanced AMD, although this was not associated with the P167S polymorphism. Electron microscopy of membrane attack complexes (MACs) generated using recombinantly produced wild type or P167S C9 demonstrated identical MAC ring structures. In functional assays, the P167S variant displayed a higher propensity to polymerize and a small increase in its ability to induce hemolysis of sheep erythrocytes when added to C9-depleted serum. The demonstration that this C9 P167S AMD risk polymorphism displays increased polymerization and functional activity provides a rationale for the gene therapy trials of sCD59 to inhibit the terminal pathway of complement in AMD that are underway.

Primary pneumococcal peritonitis can be the first presentation of a familial complement factor I deficiency1

Primary pneumococcal peritonitis is a rare infection that has been described in women but has not been previously linked with immunodeficiency. The complement system plays a central role in immune defence against Streptococcus pneumoniae and, in order to evade complement attack, pneumococci have evolved a large number of mechanisms that limit complement‐mediated opsonization and subsequent phagocytosis. We investigated an apparently immunocompetent woman with primary pneumococcal peritonitis and identified a family with deficiency for complement factor I. Primary pneumococcal peritonitis should be considered a possible primary immunodeficiency presentation.

Genetic and pharmacologic modulation of cementogenesis via pyrophosphate regulators

Pyrophosphate (PP_i) serves as a potent and physiologically important regulator of mineralization, with systemic and local concentrations determined by several key regulators, including: tissue-nonspecific alkaline phosphatase (ALPL gene; TNAP protein), the progressive ankylosis protein (ANKH; ANK), and ectonucleotide pyrophosphatase/phosphodiesterase 1 (ENPP1; ENPP1). Results to date have indicated important roles for PP_i in cementum formation, and we addressed several gaps in knowledge by employing genetically edited mouse models where PP_i metabolism was disrupted and pharmacologically modulating PP_i in a PP_i-deficient mouse model. We demonstrate that acellular cementum growth is inversely proportional to PP_i levels, with reduced cementum in Alpl KO (increased PP_i levels) mice and excess cementum in Ank KO mice (decreased PP_i levels). Moreover, simultaneous ablation of Alpl and Ank results in reestablishment of functional cementum in dKO mice. Additional reduction of PP_i by dual deletion of Ank and Enpp1 does not further increase cementogenesis, and PDL space is maintained in part through bone modeling/remodeling by osteoclasts. Our results provide insights into cementum formation and expand our knowledge of how PP_i regulates cementum. We also demonstrate for the first time that pharmacologic manipulation of PP_i through an ENPP1-Fc fusion protein can regulate cementum growth, supporting therapeutic interventions targeting PP_i metabolism.

Paradoxical aortic stiffening and subsequent cardiac dysfunction in Hutchinson-Gilford progeria syndrome

Hutchinson-Gilford progeria syndrome (HGPS) is an ultra-rare disorder with devastating sequelae resulting in early death, presently thought to stem primarily from cardiovascular events. We analyse novel longitudinal cardiovascular data from a mouse model of HGPS (Lmna^G609G/G609G) using allometric scaling, biomechanical phenotyping, and advanced computational modelling and show that late-stage diastolic dysfunction, with preserved systolic function, emerges with an increase in the pulse wave velocity and an associated loss of aortic function, independent of sex. Specifically, there is a dramatic late-stage loss of smooth muscle function and cells and an excessive accumulation of proteoglycans along the aorta, which result in a loss of biomechanical function (contractility and elastic energy storage) and a marked structural stiffening despite a distinctly low intrinsic material stiffness that is consistent with the lack of functional lamin A. Importantly, the vascular function appears to arise normally from the low-stress environment of development, only to succumb progressively to pressure-related effects of the lamin A mutation and become extreme in the peri-morbid period. Because the dramatic life-threatening aortic phenotype manifests during the last third of life there may be a therapeutic window in maturity that could alleviate concerns with therapies administered during early periods of arterial development.

The role of ADAMTS-13 activity and complement mutational analysis in differentiating acute thrombotic microangiopathies

ESSENTIALS: Molecular diagnostics has improved the differentiation of acute thrombotic microangiopathys (TMAs). Atypical hemolytic uremic syndrome may have features mimicking thrombotic thrombocytopenic purpura. We identified novel complement mutations and a high incidence of CD46, with favorable long term outcomes. Complement mutation analysis in TMA where the diagnosis is unclear and ADAMTS-13 activity is >10%.

BACKGROUND

Differentiation of acute thrombotic microangiopathy (TMA) at presentation has historically been dependent on clinical parameters. Confirmation of thrombotic thrombocytopenic purpura (TTP) is increasingly reliant on demonstrating deficient ADAMTS-13 activity. The identification of alternative complement pathway abnormalities in atypical hemolytic uremic syndrome (aHUS), along with the proven efficacy of terminal complement inhibitors in treatment, has increased the need for rapid differentiation of TTP from aHUS.

OBJECTIVES

We describe the clinical phenotype and nature of complement mutations in a cohort of aHUS patients referred as acute TMAs.

PATIENTS/METHODS

Fourteen consecutive aHUS patients were screened for mutations in C3, CD46, CFH, CFI, and CFB, as well as factor H (FH) antibodies. All aHUS patients had ADAMTS-13 activity > 10%.

RESULTS

Of 14 aHUS patients, 11 (79%) had platelet counts < 30 × 10(9) /L during the acute phase. Median presenting creatinine level was 295 μmol L(-1) , while five (36%) of 14 presented with a serum creatinine level < 200 μmol L(-1) . Alternative complement pathway mutations were detected in 9 (64%) of 14 patients, including CD46 mutations in five (36%) of 14 patients. Patients were identified with novel mutations in CFB and C3 that have not been previously reported.

CONCLUSIONS

We demonstrate that diagnostic differentiation based on platelet count and renal function is insufficient to predict an underlying complement mutation in some aHUS cases. Specifically, we demonstrate a high frequency of functionally significant CD46 mutations which may mimic TTP. ADAMTS-13 activity > 10% in a patient with a TMA should necessitate genetic screening for complement abnormalities.

A national specialized service in England for atypical haemolytic uraemic syndrome-the first year's experience

BACKGROUND

In 2013 NHS England commissioned the use of eculizumab for both new patients with atypical haemolytic uraemic syndrome (aHUS) and those undergoing transplantation. This national service is delivered locally but coordinated by an expert centre at the Newcastle upon Tyne Hospitals NHS Foundation Trust.

RESULTS

In the first year of service, 43 aHUS patients received eculizumab, 15 children and 28 adults. Twenty-three were new patients and 20 prevalent. Fifteen of the 23 new patients required dialysis before eculizumab was started, 8 of these recovered renal function. Twelve of the 20 prevalent patients who received eculizumab were transplant patients, 8 with prophylactic use and 4 for recurrent disease; the outcome in all was good. Eculizumab was withdrawn in 14 patients, 5 were patients who had not recovered renal function. In 3 of the 14 patients, it was necessary to reintroduce eculizumab because of recurrent disease (2 extra-renal and 1 renal). There were 2 deaths in the 43 patients, and neither was associated with use of eculizumab. There were no episodes of meningococcal disease.

CONCLUSIONS

The establishment of this national service has enabled aHUS patients in England to receive eculizumab when they need it for as long as they need it.

Association analysis of Notch pathway signalling genes in diabetic nephropathy

AIMS/HYPOTHESIS

Several studies have provided compelling evidence implicating the Notch signalling pathway in diabetic nephropathy. Co-regulation of Notch signalling pathway genes with GREM1 has recently been demonstrated and several genes involved in the Notch pathway are differentially expressed in kidney biopsies from individuals with diabetic nephropathy. We assessed single-nucleotide polymorphisms (SNPs; n = 42) in four of these key genes (JAG1, HES1, NOTCH3 and ADAM10) for association with diabetic nephropathy using a case-control design.

METHODS

Tag SNPs and potentially functional SNPs were genotyped using Sequenom or Taqman technologies in a total of 1371 individuals with type 1 diabetes (668 patients with nephropathy and 703 controls without nephropathy). Patients and controls were white and recruited from the UK and Ireland. Association analyses were performed using PLINK (http://pngu.mgh.harvard.edu/∼purcell/plink/) and haplotype frequencies in patients and controls were compared. Adjustment for multiple testing was performed by permutation testing.

RESULTS

In analyses stratified by centre, we identified six SNPs, rs8708 and rs11699674 (JAG1), rs10423702 and rs1548555 (NOTCH3), rs2054096 and rs8027998 (ADAM10) as being associated with diabetic nephropathy before, but not after, adjustment for multiple testing. Haplotype and subgroup analysis according to duration of diabetes also failed to find an association with diabetic nephropathy.

CONCLUSIONS/INTERPRETATION

Our results suggest that common variants in JAG1, HES1, NOTCH3 and ADAM10 are not strongly associated with diabetic nephropathy in type 1 diabetes among white individuals. Our findings, however, cannot entirely exclude these genes from involvement in the pathogenesis of diabetic nephropathy.

Prognostic biomarkers in squamous cell carcinoma of the anus: a systematic review

BACKGROUND

recent decades have seen combination chemoradiotherapy become the standard treatment for anal squamous cell carcinoma (SCC). However, the burden of this disease continues to rise, with only 10% of patients with metastatic disease surviving >2 years. Further insight into tumour characteristics and molecular biology may identify novel therapeutic targets. This systematic review examines current prognostic markers in SCC of the anus.

METHODS

an extensive literature search was performed to identify studies reporting on biomarkers in anal cancer in the context of clinical outcome following treatment primarily with chemoradiotherapy.

RESULTS

in all, 21 studies were included. A total of 29 biomarkers were studied belonging to 9 different functional classes. Of these biomarkers, 13 were found to have an association with outcome in at least one study. The tumour-suppressor genes p53 and p21 were the only markers shown to be of prognostic value in more than one study.

CONCLUSIONS

an array of biomarkers have been identified that correlate with survival following chemoradiotherapy in anal cancer. However, investigators are yet to identify a biomarker that has the ability to consistently predict outcome in this disease. Further studies are needed to elucidate whether these candidate biomarkers demonstrate their optimum value when they serve as targets for new therapeutic strategies.

Removal of multiple sentinel lymph nodes in patients with breast cancer: defining the "correct" node

PURPOSE

Sentinel node biopsy is routinely used for axillary staging in patients with clinical and radiological node negative breast cancer. The number of nodes removed at surgery is highly variable. A mean of 2.4 nodes is frequently seen in the larger series. Removal of multiple (3 or more) nodes does not improve the accuracy but increases both operative time and pathological analysis. The aim of the current study was to define the correct sentinel node based on uptake of blue dye and radioactive counts.

METHODS

The sentinel node was identified in 121 consecutive patients using isosulfan blue dye and radioisotope. Nodes were labelled sequentially as (i) Hot (ii) Blue or (iii) Hot and Blue and submitted for pathological analysis. Data pertaining to blue dye uptake and radioisotope counts were recorded prospectively. This was correlated with pathological and scintigraphy findings.

RESULTS

Thirty eight (32%) patients had a positive sentinel node. "Hot and Blue" nodes were found in 105 cases. The number of hot and blue nodes correlated exactly with the number seen on scintigraphy. "Blue" nodes were found in one case. "Hot" nodes were found in 15 cases. In cases where a "hot and blue" node was positive there were no further "hot" or "blue" nodes found to be positive.

CONCLUSION

Removal of multiple sentinel nodes can be avoided by removing all hot and blue nodes and correlating with findings on lymphoscintigraphy. When present (87% of cases), the "hot and blue" node accurately predicts the pathological burden of the axilla.

Acute dyspnoea due to an incarcerated right-sided Bochdalek's hernia

We present the case of a 76-year-old man with a right-sided Bochdalek hernia, admitted acutely with dyspnoea, abdominal distension and constipation. A chest radiograph and computed tomogram of the abdomen revealed marked elevation of the right hemidiaphragm caused by herniation of the colon. At laparotomy, strangulation of a portion of transverse colon was identified at the site of the foramen of Bochdalek. The contents of the hernia were reduced and a primary repair of the hernial orifice was performed. The segment of necrosed colon was resected and an end-to-end handsewn anastomosis was constructed. A symptomatic Bochdalek hernia typically presents as a cardiorespiratory emergency in the neonatal period. It can remain silent and present in adulthood with chronic gastro-intestinal or respiratory symptoms. Occasionally it presents with acute dyspnoea or abdominal pain. Early detection and intervention is of the utmost importance to decrease related morbidity and mortality in adults.

Laparoscopic peritoneal lavage for generalized peritonitis due to perforated diverticulitis

BACKGROUND

The standard approach to generalized peritonitis due to perforated diverticulitis involves open surgery and diversion of faecal content. This study assessed the feasibility of laparoscopic peritoneal lavage.

METHODS

A prospective multi-institutional study of 100 patients was undertaken. All consenting patients with perforated diverticulitis causing generalized peritonitis underwent attempted laparoscopic peritoneal lavage. The degree of peritonitis, according to the Hinchey grading system, was recorded. Primary endpoints were operative success and resolution of symptoms.

RESULTS

Patients had a median age of 62.5 (range 39-94) years, a male : female ratio of 2 : 1 and a median American Society of Anesthesiologists grade of III (range II-V). Eight patients with grade 4 diverticulitis had conversion to an open Hartmann's procedure. The remaining 92 patients were managed by laparoscopic lavage, with morbidity and mortality rates of 4 and 3 per cent respectively. Two patients required postoperative intervention for a pelvic abscess. Only two patients re-presented with diverticulitis at a median follow up of 36 (range 12-84) months.

CONCLUSION

Laparoscopic management of perforated diverticulitis with generalized peritonitis is feasible, with a low recurrence risk in the short term.

The decay accelerating factor mutation I197V found in hemolytic uraemic syndrome does not impair complement regulation

Hemolytic uremic syndrome is the clinical triad of thrombocytopenia, microangiopathic hemolytic anaemia and acute renal failure. Cases not associated with a preceding Shiga-like toxin producing Escherichia coli are described as atypical HUS (aHUS). Approximately 50% of patients with aHUS have mutations in one of three complement regulatory proteins, Factor H (CFH), membrane cofactor protein (MCP;CD46) or factor I (IF). A common feature of these three proteins is that they regulate complement by cofactor activity. Decay accelerating factor (DAF; CD55) regulates the complement system by disassociating the alternative and classical pathway convertases. Like CFH and MCP, the gene for DAF lies within the regulators of complement activation (RCA) gene cluster at 1q32. In 1998, we described linkage to this region in families with aHUS which led to the discovery of mutations in CFH and MCP. We therefore genotyped DAF in a panel of 46 aHUS patients including families with linkage to the RCA cluster. A mutation, I197V, was identified in one patient with familial HUS which was not found in 100 healthy controls. Molecular modelling of this mutation shows that the I197V mutation does not reside in an area which would be predicted to be important in decay accelerating activity. The expression of I197V on EBV-transformed B lymphocytes was equivalent to that of wild type controls. There was no significant decrease in decay acceleration activity of the recombinantly produced I197V mutant compared with wild type, as measured by a complement-mediated lytic assay. In conclusion, this study, identifies only one mutation in DAF in 46 patients with aHUS. This mutation, I197V, does not impair complement regulation and cannot be implicated in the pathogenesis of aHUS in this patient. This suggests that the complement regulatory abnormality in aHUS is principally one of deficient cofactor activity rather than of decay acceleration activity.

Adjuvant therapies in the treatment of stage II and III malignant melanoma

BACKGROUND

The incidence of cutaneous melanoma has increased during the past three decades. The development of sentinel lymph node biopsy has facilitated better staging. Despite these improvements, 5-year survival rates for American Joint Committee on Cancer stage II and III disease range from 50%-90%.

METHODS

A review of the current literature concerning adjuvant therapies in patients with stage II and III malignant melanomas was undertaken.

RESULTS

The focus of adjuvant therapies has shifted from radiotherapy, BCG and levamisole to newer biological agents. Interferon, interleukin and vaccines have been evaluated but none of these agents have demonstrated an increase in overall survival in patients with stage II and III melanoma. Interferon can prolong disease-free interval.

CONCLUSION

At present, no adjuvant therapy improves overall survival in patients with stage II and III melanoma. New staging allows more accurate stratification of patients for clinical trials.

Meralgia paraesthetica following open appendicectomy

Meralgia paraesthetica is a painful condition attributed to entrapment or injury to the lateral femoral cutaneous nerve. It has been described following operations which could result in direct injury to the nerve such as iliac crest bone harvesting. It has also been reported following surgery remote from the nerve. Following open appendicectomy injury may occur following direct trauma to an anatomical variant of this nerve, which can occur in up to 25% of the population. We report two cases that became clinically evident immediately following open appendicectomy with subsequent confirmatory electromyography studies. Meralgia paraesthetica following open appendicectomy has not been reported in the medical literature. This is an under-recognised complication of open appendicectomy. Management can be challenging for patient and clinician.

Diagnosis and treatment of enterovesical fistulae

OBJECTIVE

Enterovesical fistulae are a recognized complication of a variety of inflammatory and neoplastic conditions. Despite advances in imaging and treatment the diagnosis may be delayed and the management remains diverse. We describe our experience with their diagnosis and management.

PATIENTS AND METHODS

This retrospective study encompassed all patients referred over a 10-year period with clinical suspicion of or confirmed enterovesical fistula. Demographics, clinical presentation, aetiology and clinical outcome were evaluated. Mean follow-up was 18 months (range 6-50 months).

RESULTS

Thirty patients were studied. The mean age was 63.5 years (range 23-92 years). Fifteen (50%) patients presented with classical urinary symptoms (pneumaturia, faecaluria and recurrent urinary tract infections). The commonest investigations (n, % positive) included CT (15, 80), cystoscopy (16, 87.5), endoscopy (11, 54.5) and barium enema (8, 50). There were 20 inflammatory and 10 neoplastic aetiologies. Five patients were treated conservatively and 25 patients underwent surgery. Surgery resulted in symptomatic cure in the majority of cases (22/25).

CONCLUSION

Classical urinary symptoms were only evident in 50% of patients with confirmed fistulae. We advocate CT scanning as the optimum imaging modality before surgical intervention. Surgical treatment in a specialized unit remains the most effective treatment of enterovesical fistulae.

Needle-localised biopsy of impalpable breast lesions: A novel adjunct to surgical technique and specimen mammography

Successful screening programmes have resulted in the more frequent detection of early impalpable breast tumours. Effective surgical management of impalpable lesions demands a precise approach to excision which is currently aided by radiologically guided needle-localisation of the lesion prior to operative removal. The surgical specimen procured is most commonly evaluated for tumour presence by specimen mammography intra-operatively or by histological analysis. The latter is more accurate but requires lengthy laboratory processing, which may result in re-operation if the primary excision is inadequate. Although advocated as the standard of care, specimen mammography remains an imperfect technique. In this article we describe a piece of surgical apparatus which attempts to address some of the concerns associated with specimen mammography. It is an inexpensive compression device which reduces operative time, avoids portable fluoroscopy, increased radiation and the necessity for specialised equipment

Factors affecting metastases to non-sentinel lymph nodes in breast cancer

AIMS

Because sentinel lymph node (SLN) biopsy for breast cancer has become well established, one of the challenges now is to determine which patients require a completion axillary dissection following a positive SLN biopsy.

METHODS

A prospective database of patients who underwent SLN biopsy for invasive breast cancer from July 1999 to November 2002 (n = 180) was analysed. Fifty four patients (30%) had one or more positive SLN, and all underwent a completion axillary dissection. This subgroup was further analysed to delineate which factors predicted non-SLN metastasis.

RESULTS

Twenty six of the 54 patients with a positive SLN had additional metastases in non-SLNs. Significant variables that predicted non-SLN metastasis included extranodal extension (odds ratio (OR), 17.399; 95% confidence interval (CI), 1.69 to 178.96) and macrometastasis within the SLN (OR, 6.985; 95% CI, 1.291 to 37.785).

CONCLUSIONS

In patients with invasive breast cancer and a positive SLN, extranodal extension or macrometastasis within the SLN were both independent predictors of non-SLN involvement.

Intradermal radioisotope injection optimises sentinel lymph node identification in breast cancer

AIM

Currently there is no consensus on the optimal technique for sentinel lymph node (SLN) identification in patients with breast cancer. The aim was to compare the efficacy of intraparenchymal and intradermal isotope injection in sentinel lymph node mapping for breast cancer.

METHODS

One hundred and twenty-five patients with histologically confirmed invasive breast cancer underwent SLN mapping using radioisotope and isosulphan blue dye followed by a back-up axillary dissection. The first 80 patients had intraparenchymal (IP) injection of radioisotope given in four portions around the tumor. The remaining 45 patients had an intradermal (ID) injection given at a single site over the tumour. Both groups had isosulphan blue dye injected around the tumour. Sentinel node(s) were identified using a combination of lymphoscintigraphy, blue dye and an intra-operative hand held gamma probe.

RESULTS

The preoperative lymphoscintigram (LSG) demonstrated a SLN significantly more often in the ID isotope group compared to the IP isotope group (P=0.002). A combination of blue dye and isotope successfully located the SLN in 96% of the intraparenchymal group and 100% of the intradermal group.

CONCLUSION

Our results suggest that intradermal isotope injection in combination with intraparenchymal blue dye optimises the localization of the sentinel lymph node in breast cancer.

An examination of the utility of the AUDIT in people with schizophrenia

OBJECTIVE

To examine the reliability and validity of the Alcohol Use Disorders Identification Test (AUDIT) compared to a structured diagnostic interview, the Composite International Diagnostic Interview (CIDI; 12-month version) in psychiatric patients with a diagnosis of schizophrenia.

METHOD

Patients (N = 71, 53 men) were interviewed using the CIDI (Alcohol Misuse Section; 12-month version) and then completed the AUDIT.

RESULTS

The CIDI identified 32.4% of the sample as having an alcohol use disorder. Of these, 5 (7.0%) met diagnostic criteria for harmful use of alcohol, 1 (1.4%) met diagnostic criteria for alcohol abuse and 17 (23.9%) met diagnostic criteria for alcohol dependence. The AUDIT was found to have good internal reliability (coefficient = 0.85). An AUDIT cutoff of > or = 8 had a sensitivity of 87% and specificity of 90% in detecting CIDI-diagnosed alcohol disorders. All items except Item 9 contributed significantly to discriminant validity.

CONCLUSIONS

The findings replicate and extend previous findings of high rates of alcohol use disorders in people with severe mental illness. The AUDIT was found to be reliable and valid in this sample and can be used with confidence as a screening instrument for alcohol use disorders in people with schizophrenia.

Fluoride in tea--its dental significance: a review

It has long been accepted that fluoride accumulates in the leaves of the tea plant. Camellia sinensis. In addition it is known that some of this fluoride is released into the infusion which is drunk as tea. The exact concentration of fluoride in a cup of tea and the effects of this fluoride have been the subject of many international studies. This review summarizes the main points of such studies which have been carried out in an attempt to establish the dental significance of fluoride in tea. The most popular teas in Ireland are not readily available in any other country and therefore, Irish data may not be assumed to be similar to those in the studies reviewed here. By identifying potential sources of high fluoride ingestion, recommendations can be made to reduce consumption from these sources in patients who may be at risk of dental fluorosis. In conclusion, it is recommended that a research project be carried out to analyse the fluoride levels released and the rates of the releases from teas available on the Irish market. Ireland has the highest per capita consumption of tea in the world.

An in vitro evaluation of canal preparation using Profile .04 and .06 taper instruments

A model system involving a double radiographic exposure technique was developed in order to evaluate maintenance of the original canal path of curved root canals. The mesiobuccal roots of 30 maxillary molars were prepared using one of three techniques (n = 10 in each group). One group was instrumented using rotary Profile .04 tapers and a second group was prepared using orifice openers, rotary Profile .04 and .06 tapers. The final group was prepared using Profile hand files .02 taper and Gates-Glidden drills. Canal transportation was evaluated in the apical, middle and coronal regions from the double-exposed radiographs. Canal shape was determined by the ease with which a D11T spreader passed to within 1 mm of the working length. Time of instrumentation was also recorded. The results showed no significant difference between the techniques in canal transportation in the apical, middle or coronal regions (P > 0.05). It was significantly easier to place the D11T spreader in the .06 taper group (P < 0.05). Canal preparation was significantly quicker in the .04 taper group (P < 0.05). In conclusion, the use of .06 taper files improved canal shape and did not increase transportation. The additional file changes, however, increased the instrumentation time.

A three-year clinical trial of a combination of trimetaphosphate and sodium fluoride in silica toothpastes

The relative efficacy of NaF silica toothpastes containing 1000 ppm fluoride and 1500 ppm fluoride in the control of dental caries is not clear-cut. Also, it has not been established that incorporation of trimetaphosphate (TMP) improves the anticaries activity of NaF toothpastes. A three-year clinical trial was conducted to test the hypotheses that: (i) the anticaries activity of NaF toothpastes containing 1500 ppm F was greater than that of NaF toothpastes containing 1000 ppm F, and (ii) inclusion of TMP improved the efficacy of NaF silica pastes. Subsidiary aims included determination of whether frequency of toothbrushing and method of rinsing after brushing were correlated with caries increments. The study involved 4196 children aged 11 to 12 years at outset. These participants had been selected from a pool of 7374 potential subjects on the basis of caries experience and dental eruption pattern. They were stratified by sex, examiner, and presence of calculus and caries, and were allocated at random to one of the four toothpastes under study. Using mirror and probe and also FOTI, we carried out clinical examinations at baseline and annually thereafter for 3 yrs. Bitewing radiographs of a subset of children were taken at baseline and at the end of the study. The outcome measure for the study, DMFS increment, was defined as the increase in caries over 3 yrs, taking into account changes occurring on individual tooth surfaces. Data for 3467 subjects were available for analyses at both baseline and year 3 examinations. Radiographs were taken for 1942 subjects at both baseline and year 3 examinations. The mean three-year clinical-only DMFS increment for the subjects using 1500-ppm-NaF pastes was 3.93, which was 6% lower than the corresponding mean of 4.19 for the 1000-ppm-NaF pastes. There was no significant difference between the mean DMFS increment for those using paste with or without TMP. Subjects who claimed to brush more frequently or who claimed not to use a tumbler to rinse after toothbrushing had lower three-year DFMS increments.

Eye-movements and visual imagery: a working memory approach to the treatment of post-traumatic stress disorder

It has been claimed that the symptoms of post-traumatic stress disorder (PTSD) can be ameliorated by eye-movement desensitization-reprocessing therapy (EMD-R), a procedure that involves the individual making saccadic eye-movements while imagining the traumatic event. We hypothesized that these eye-movements reduce the vividness of distressing images by disrupting the function of the visuospatial sketchpad (VSSP) of working memory, and that by doing so they reduce the intensity of the emotion associated with the image. This hypothesis was tested by asking non-PTSD participants to form images of neutral and negative pictures under dual task conditions. Their images were less vivid with concurrent eye-movements and with a concurrent spatial tapping task that did not involve eye-movements. In the first three experiments, these secondary tasks did not consistently affect participants' emotional responses to the images. However, Expt 4 used personal recollections as stimuli for the imagery task, and demonstrated a significant reduction in emotional response under the same dual task conditions. These results suggest that, if EMD-R works, it does so by reducing the vividness and emotiveness of traumatic images via the VSSP of working memory. Other visuospatial tasks may also be of therapeutic value.

Treatment of multiple sclerosis with T-cell receptor peptides: results of a double-blind pilot trial

A T-cell receptor (TCR) peptide vaccine from the V beta 5.2 sequence expressed in multiple sclerosis (MS) plaques and on myelin basic protein (MBP)-specific T cells boosted peptide-reactive T cells in patients with progressive MS. Vaccine responders had a reduced MBP response and remained clinically stable without side effects during one year of therapy, whereas nonresponders had an increased MBP response and progressed clinically. Peptide-specific T helper 2 cells directly inhibited MBP-specific T helper 1 cells in vitro through the release of interleukin-10, implicating a bystander suppression mechanism that holds promise for treatment of MS and other autoimmune diseases.

Use of environmental manipulation and modified informal reality orientation with institutionalized, confused elderly subjects: a replication

The effectiveness, for confused elderly subjects, of modified informal reality orientation and environmental manipulation without any 'classroom' reality orientation was investigated with 10 experimental subjects in one ward and 10 control subjects in another. All subjects were assessed prior to the start of the intervention and after 6 and 12 weeks of treatment on cognitive and behavioural measures. While the control group showed decline on all measures except one, the experimental group improved in ward orientation and cognitive status and showed no decline on the behavioural measures.