Mobility in Community Dwelling Older Adults: Predicting Successful Mobility Using an Instrumented Battery of Novel Measures

Mobility in older adults is associated with better quality of life. However, evidence suggests that older people spend less time out-of-home than younger adults. Traditional methods for assessing mobility have serious limitations. Wearable technologies provide the possibility of objectively assessing mobility over extended periods enabling better estimates of levels of mobility to be made and possible predictors to be explored. Eighty-six community dwelling older adults (mean age 79.8 years) had their mobility assessed for one week using GPS, accelerometry and self-report. Outcomes were: number of steps, time spent in dynamic outdoor activity, total distance travelled and total number of journeys made over the week. Assessments were also made of personal, cognitive, psychological, physical and social variables. Four regression models were calculated (one for each outcome). The models predicted 32 to 43% of the variance in levels of mobility. The ability to balance on one leg significantly predicted all four outcomes. In addition, cognitive ability predicted number of journeys made per week and time spent engaged in dynamic outdoor activity, and age significantly predicted total distance travelled. Overall estimates of mobility indicated step counts that were similar to those shown by previous research but distances travelled, measured by GPS, were lower. These findings suggest that mobility in this sample of older adults is predicted by the ability to balance on one leg. Possible interventions to improve out-of-home mobility could target balance. The fact that participants travelled shorter distances than those reported in previous studies is interesting since this high-functioning subgroup would be expected to demonstrate the highest levels.

Effects of radiotherapy to the jaws. 2: Potential solutions

Dental maintenance and rehabilitation of head and neck cancer care is becoming more important as the outcome of cancer treatment improves. The management of these patients can be very difficult for a number of reasons as discussed in part one of this two-part series. This second part attempts to suggest possible solutions for the management of the major oral health problems encountered by these patients during and after their cancer treatment.

Effects of radiotherapy to the jaws. I: The scale of the problem

Cancer care has become one of the main targets of the National Health Service in England and with cancer patients surviving longer, it is likely that head and neck cancer patients will make up a large proportion of patients seen within secondary care settings in the future. The management of these patients can be very difficult for a number of reasons. Part one of this paper attempts to highlight the major oral health problems encountered by these patients during and after their cancer treatment and supported by the current literature. Part two of this series will address the dental management of head and neck oncology patients undergoing radiotherapy with particular attention of possible improvement to current management strategies for these patients.

The oestrogen ‘sparing’ effect of implanon: A case report and review

This article presents a case study of the 'oestrogen sparing effect' of etonorgestrel especially high lighting its use in a patient with hypoestrogenism following long-term use of depomedroxyprogesterone acetate (DMPA); still wishing a long-term reversible method of contraception. There are studies demonstrating the effects of both DMPA and etonogestrel on estrogen status, but evidence is sparse, exploring the possibilities of usage of etonorgestrel following demonstration of hypo-oestrogenism with DMPA usage.

Screening for pulmonary tuberculosis: an acceptable intervention for antenatal care clients and providers?

SETTING

Five purposively sampled health facilities in Kasungu District, Malawi.

OBJECTIVES

To explore 1) the acceptability of introducing pulmonary tuberculosis (PTB) screening into antenatal care (ANC) clinics amongst ANC clients and ANC service providers; and 2) the acceptability of tuberculosis (TB) treatment during and after pregnancy among women registered for TB treatment.

METHODS

Fourteen focus group discussions and 40 in-depth interviews with ANC clients (15), ANC service providers (10) and women registered for TB treatment (15).

RESULTS

Most clients found the introduction of PTB screening into ANC clinics acceptable. Some expressed concern at submitting a second sputum specimen, citing transportation/distance as the main obstacle. Other concerns were stigma and fear relating to the human immunodeficiency virus and the acquired immune-deficiency syndrome (HIV/AIDS) and taking TB treatment during pregnancy and breast-feeding. All ANC service providers supported the idea, but were concerned about increased workload.

CONCLUSION

PTB screening in the ANC setting would be an acceptable intervention and could serve to increase PTB case notification in Malawi. However, alternative diagnostic strategies need to be explored. The negative associations with HIV/AIDS and some of the misconceptions surrounding TB treatment need to be addressed to avoid PTB screening becoming a potential barrier to seeking ANC. The main challenge will be whether over-stretched staff will be able to cope with this additional service.

CliniMACS CD34-selected cells to support multiple cycles of high-dose therapy

BACKGROUND

Traditionally, following high-dose therapy (HDT), unmanipulated autologous PBPC are infused. Alternatively, purified CD34+ cells can now be obtained by immunomagnetic separation using the CliniMACS device. Limited data currently exist examining hemopoietic recovery with such cells.

METHODS

Ten patients with advanced breast cancer had PBPC mobilized with docetaxel (100 mg/m2) and G-CSF (10 microg/kg per day), harvested and processed using the CliniMACS CD34-selection device and equally divided into three aliquots for cryopreservation. Unmanipulated 'back-up' cells were also collected on a separate day of the same mobilization, divided into three and cryopreserved. Patients subsequently received three cycles of HDT with cyclophosphamide (4 g/m2), thiotepa (300 mg/m2) and paclitaxel (175 mg/m2). The intent was for patients to receive CD34-selected cells to support each of the three cycles of HDT (i.e., 1/3 for each cycle). If, however, hemopoietic recovery was delayed after Cycle 1, 1/3 of the unmanipulated cells were infused following Cycle 2 and the remaining CD34-selected cells (2/3) were used to support Cycle 3.

RESULTS

PBPC from 10 patients underwent CD34-selection with a resulting median purity of 93% (range: 76-98%) and yield of 62% (range: 16-93%). Of the 10 patients, only two were able to be supported with CD34-selected cells for all three cycles of HDT. The remaining eight patients required unmanipulated 'back-up' cells to support Cycle 2. Three patients also required infusion of 'back-up' unmanipulated cells because of persistent neutropenia (n = 1) or thrombocytopenia (n = 2) following cycles initially supported by CD34-selected cells. The median number of CD34-selected cells (x 10(6)/kg) infused per cycle was 1.5 (0.7-2.6) (n = 20) and unselected cells was 1.7 (1.4-2.8) (n = 10). Comparing hemopoietic recovery between cycles of HDT supported by CD34-selected (n = 20) and unmanipulated cells (n = 10) there was a significant slowing with the CD34-selected cells; time to ANC > 1.0 = 13 days versus 10 days, platelets > 20 = 17 days versus 13 days, > 50 = 25 versus 17 days (all P values < 0.001). There was no correlation between the dose of CD34-selected cells infused and neutrophil/platelet recovery.

DISCUSSION

We have demonstrated that, although unmanipulated PBPC achieve rapid hemopoietic recovery (at modest CD34 doses of < or = 2.8 x 10(6)/kg), CliniMACS-selected CD34+ cells (in the doses utilized in this study of < or = 2.6 x 10(6)/kg) result in significantly prolonged recovery.

Isolex 300i CD34-selected cells to support multiple cycles of high-dose therapy

BACKGROUND

We have previously reported that repeated cycles of high-dose therapy (HDT), can be supported by unmanipulated autologous PBPC. Here we investigate whether purified CD34+ cells, obtained by immunomagnetic separation using the Isolex 300i device, can support such therapy.

METHODS

Twenty-nine consecutive patients with metastatic breast cancer had PBPC mobilized and harvested following chemotherapy and G-CSF (10 microg/kg per day). Patients with > 4.0 x 10(6)/kg CD34+ cells in the apheresis product underwent CD34-selection using the Isolex 300i (v2.0) device. All cells collected were equally divided into three aliquots and cryopreserved. Patients who did not achieve this threshold had unmanipulated cells collected and stored. Patients subsequently received three cycles of HDT with paclitaxel (175 mg/m2), thiotepa (300 mg/m2) and either ifosfamide (10 g/m2) or cyclophosphamide (4 g/m2). It was intended for patients to receive CD34-selected cells to support each of the three cycles of HDT (i.e 1/3 for each cycle) and to compare hemopoietic recovery between patients receiving CD34-selected cells or unmanipulated cells.

RESULTS

Thirteen of the 29 patients (45%) did not mobilize sufficient CD34+ cells to undergo CD34-selection. The remaining 16 patients underwent CD34-selection with a median purity of 84.3% (range: 16.3-96.1%) and yield of 34% (range: 1-60%). Fifteen of these patients proceeded to HDT and 42 of the planned 45 cycles were administered. Nine patients had all three HDT cycles supported by CD34-selected cells. The median number of CD34-selected cells (x 10(6)/kg) infused per cycle was 1.5 (range: 0.04-3.01). Three of the 15 patients required infusion of 'back-up' unmanipulated cells because of delayed neutrophil recovery. Of the 13 patients whose PBPCs did not undergo CD34+ cell selection, 11 proceeded to HDT with a median of 3.2 x 10(6)/kg (range: 2.0-4.4) unselected cells infused per cycle and 31 of 33 planned cycles were delivered. When hemopoietic recovery was compared between cycles of HDT supported by CD34-selected (n = 34) and unmanipulated cells (n = 31), there was a modest slowing in the patients receiving CD34-selected cells; time to ANC > 1.0 x 10(9)/L = 11 days versus 10 days (P = 0.0122) and platelets > 20 x 10(9)/L = 14 days versus 13 days (P = 0.0009). No difference in recovery to 50 x 10(9)/L was observed (P = 0.54).

CONCLUSION

We have demonstrated that Isolex 300i CD34-selected cells are capable of supporting multiple cycles of HDT. However, we were unable to acquire sufficient CD34+ cells to perform this processing in 45% (13/29) of patients and further improvements in yield are required to overcome the modest delay in neutrophil and platelet recovery.

Isolated dorsal dislocation of the 5th carpometacarpal joint

Injuries to the carpometacarpal (CMC) joints are uncommon injuries and isolated dislocation of these joints occurs very infrequently. The 4th and 5th CMC joints are predominantly involved in CMC joint injuries. The detection of CMC joint injuries requires a high index of suspicion and often depends on special radiographic views. This article present a case report of a mid-shaft fracture of the 4th metacarpal which was associated with an isolated dislocation of the 5th CMC joint. An overview of the incidence, mechanism of injury, anatomy, clinical and radiological assessment of injuries involving dorsal dislocation of the 5th carpometacarpal joint is presented.

Repetitive high-dose therapy with cyclophosphamide, thiotepa and docetaxel with peripheral blood progenitor cell and filgrastim support for metastatic and locally advanced breast cancer: results of a phase I study

This phase I study was designed to determine the optimal dosages of a novel repetitive high-dose therapy regimen for patients with metastatic breast cancer (MBC). The planned treatment was three cycles of high-dose cyclophosphamide, thiotepa and docetaxel delivered every 35 days with progressive dose-escalation in successive cohorts. Each cycle was supported by peripheral blood progenitor cells (PBPC) and filgrastim. Eighteen patients were entered into this trial. Of the planned 54 treatment cycles, 44 were delivered and 11 patients completed all three cycles. The dose-limiting toxicities were interstitial pneumonitis and mucositis with moderately severe diarrhea (n = 3) and rash (n = 3). There were no treatment-related deaths. Of the 17 patients with evaluable disease, 16 patients responded with six patients achieving a complete remission and an additional four patients achieving no detectable disease (negative restaging including PET scan) but a persistently abnormal bone scan. At a median follow-up of 12 months, median progression-free survival was 11 months with the median overall survival not reached. The recommended doses for phase II/III studies are cyclophosphamide (4 g/m2), thiotepa (300 mg/m2) and docetaxel (100 mg/m2).

Docetaxel effectively mobilizes peripheral blood CD34+ cells

We prospectively evaluated docetaxel (100 mg/m2) with G-CSF (10 microg/kg S.C., daily) for mobilization efficiency in 26 patients with breast cancer. The minimum target yield was >4.5 x 10(6) CD34+ cells/kg (optimum = 9 x 10(6)/kg), sufficient to support the subsequent three cycles of high-dose therapy (HDT). The peak days for peripheral blood (PB) CD34+ cells were day 8 and day 9. Seven collections began on day 7, 16 on day 8 and three on day 9. The median peripheral blood progenitor cell (PBPC) CD34+ cell content ranged from 1.2 to 5.9 x 10(6)/kg per day during days 7 to 11 with a median CD34+ content of the total 72 PBPC collections of 3.4 x 10(6)/kg (0.07-15.6). Fifteen patients obtained a PBPC collection exceeding 5 x 10(6)/kg on a single day of collection. Following a median 3 days collection for each patient (range 2-4), the median total CD34+ for all individual sets of collections was 9.7 x 10(6)/kg (range 1.0-28.4). We were able to achieve the minimum CD34+ cell target yield in 22 of 26 patients with one cycle of mobilisation chemotherapy and in two of these patients a second collection yielded sufficient cells. Twenty-two patients have subsequently received repetitive HDT and PBPC transplantation with 57 cycles of HDT having been delivered. For all 57 cycles, the median time to absolute neutrophil count (ANC) >0.5 x 10(9)/l and 1.0 x 10(9)/l was 10 days (range 8-22) and 11 days (range 8-23), respectively. The median time to platelets greater than 20 x 10(9)/l, 50 x 10(9)/l and 100 x 10(9)/l was 13 days (range 11-23), 17 days (range 12-53) and 23 days (range 18-70), respectively. We conclude that docetaxel with G-CSF effectively mobilises PBPCs with apheresis needing to be commenced approximately 8 days after docetaxel administration.

The occlusal management of maxillary anterior single-unit implant-supported restorations

This paper, with the aid of clinical examples, highlights some of the common occlusal problems that can be associated with maxillary anterior single-unit implant-supported restorations. The authors stress the importance of thorough pre-operative planning to identify any likely occlusal problems. This allows patients to be fully informed of the impact of any necessary clinical compromise and of the need for and nature of modifications to the natural dentition.

Clinical evaluation of resin-bonded gold alloy veneers

STATEMENT OF PROBLEM

Clinical performance of resin-bonded alumina-abraded type III cast gold alloy veneers has not been reported.

PURPOSE

This retrospective study evaluated the survival of such restorations for the management of tooth wear and other restorative problems.

MATERIAL AND METHOD

This clinical study evaluated 25 patients between 14 and 60 years of age treated with a total of 158 cast gold veneers cemented with Panavia Ex cement. Restorations placed between January 1990 and February 1996 (mean age 48 months) were evaluated. Factors, including age, gender, operator, site, design, the extent of dentin exposure, the presence of previous restorations, dynamic and static occlusion, rubber dam, cause, and methods of interocclusal space creation, were evaluated with Cox regression. Survival probability was evaluated with Kaplan-Meier analyses. Significance was taken as P <.05.

RESULTS

Failures occurred for 7.6% of restorations in 28% of patients. Alumina-abraded gold alloys cemented with Panavia Ex cement had an estimated 89% survival probability at 60 months using Kaplan-Meier analyses. The only variable to statistically influence survival was operator (P <.0001). Operator differences were due to a single operator who placed only 2 restorations in the same patient, both of which failed unusually quickly.

CONCLUSION

Resin-bonded alumina-abraded type III cast gold alloys can be successfully used to restore both anterior and posterior teeth and were associated with an estimated 89% survival probability at 60 months.

The sedative and analgesic effects of detomidine-butorphanol and detomidine alone in donkeys

Butorphanol and detomidine constitute an effective combination for sedation and analgesia in horses. This trial was undertaken to assess the effectiveness of this combination in donkeys. The detomidine and butorphanol were given intravenously one after the other. A dose of 10 microg/kg of detomidine and 25 microg/kg of butorphanol was used. Sedation is easily extended by additional doses of butorphanol. The average dose of detomidine was 11.24 microg/kg and that of butorphanol was 28.0 microg/kg. Four donkeys in the detomidine group required additional sedation and analgesia. Detomidine alone did not totally eliminate coronary band pain. Heart rates dropped significantly in the first minute after the injection of the combination. One donkey developed an atrioventricular block, while another developed a sino-atrial block. Four donkeys developed a Cheyne-Stokes respiratory pattern. The combination of detomidine and butorphanol is an effective combination for sedation and analgesia of donkeys for standing procedures.

Repetitive high-dose therapy with ifosfamide, thiotepa and paclitaxel with peripheral blood progenitor cell and filgrastim support for metastatic and locally advanced breast cancer: results of a phase I study

BACKGROUND

This phase I study was designed to determine the optimal dosages of a novel repetitive high-dose therapy regimen for patients with metastatic breast cancer (MBC).

PATIENTS AND METHODS

The planned treatment was three cycles of high-dose ifosfamide, thiotepa and conventional-dose paclitaxel delivered every 28 days with progressive dose-escalation in successive cohorts. Each cycle was supported by peripheral blood progenitor cells (PBPC) and filgrastim.

RESULTS

Twenty-three patients were entered into this trial. Of the planned 69 treatment cycles, 59 were delivered and fifteen patients completed all three cycles. The dose-limiting toxicities were renal tubular acidosis, encephalopathy, mucositis and enterocolitis. There was one treatment-related hemorrhagic death.

CONCLUSIONS

The recommended doses for phase II or III studies are ifosfamide (10 g/m2), thiotepa (350 mg/m2) and paclitaxel (175 mg/m2).

Ifosfamide in combination with paclitaxel or doxorubicin: regimens which effectively mobilize peripheral blood progenitor cells while demonstrating anti-tumor activity in patients with metastatic breast cancer

For patients with metastatic breast cancer (MBC) who undergo high-dose therapy with autologous peripheral blood progenitor cell (PBPC) transplantation, an important prerequisite is a mobilization regimen that efficiently mobilizes PBPCs while producing an effective anti-tumor effect. We prospectively evaluated ifosfamide-based chemotherapy for mobilization efficiency, toxicity and disease response in 37 patients. Patients received two cycles of the ifosfamide-based regimen; ifosfamide (5 g/m2 with conventional-dose cycle and 6 g/m2 with mobilization cycle) with either 50 mg/m2 doxorubicin (if limited prior anthracycline and/or progression more than 12 months after an anthracycline-based regimen) or 175 mg/m2 paclitaxel. For the mobilization cycle, all patients received additional G-CSF (10 microg/kg SC, daily) commencing 24 h after completion of chemotherapy. The target yield was >6x10(6) CD34+ cells/kg, sufficient to support the subsequent three cycles of high-dose therapy. The mobilization therapy was well tolerated and the peak days for peripheral blood (PB) CD34+ cells were days 10-13 with no significant differences in the PB CD34+ cells mobilization kinetics between the ifosfamide-doxorubicin vs. ifosfamide-paclitaxel regimens. The median PBPC CD34+ cell content ranged from 2.9 to 4.0x10(6)/kg per day during days 9-14. After a median of 3 (range 1-5) collection days, the median total CD34+ cell, CFU-GM and MNC for all 44 individual sets of collections was 9.2x10(6)/kg (range 0.16-54.9), 37x10(4)/kg (range 5.7-247) and 7.3x10(8)/kg (range 2.1-26.1), respectively. The PBPC target yield was achieved in 35 of the 37 patients. The overall response rate for the 31 evaluable patients was 68% with 10% having progressive disease. Thirty-three patients have subsequently received high-dose therapy consisting of three planned cycles of high-dose ifosfamide, thiotepa and paclitaxel with each cycle supported with PBPCs. Rapid neutrophil and platelet recovery has been observed. Ifosfamide with G-CSF in combination with doxorubicin or paclitaxel achieves effective mobilization of PBPC and anti-tumor activity with minimal toxicity.

Young adult patients with established dental erosion--what should be done?

This clinical paper discusses the problem of managing established erosion in the young patient. For a significant number of these patients it is not possible to establish conclusively the erosive source. Intermediate composite restorations, in addition to the use of normal preventive measures, can be used to protect eroded teeth from further damage. The main goal of such restorations is to protect the viability of the worst-affected teeth until such time as the aetiological factors can be identified and controlled. They can also improve overall aesthetics and create interocclusal space.

Degradation of a silver point in association with endodontic infection

This paper describes an unusual clinical report of degradation of an endodontic silver point within the root canal of a lower right first premolar. Its apical portion was found to be degrading and at one stage a small portion became separated from its main body and was displaced apically. The tooth, despite past apical surgery, displayed signs of endodontic failure. Conventional retreatment and removal of the silver point improved the endodontic problems associated with this tooth. The silver point was analysed using both scanning electron microscopy and x-ray microanalyses. These tests revealed that the silver point had deteriorated significantly with a surface coating of a silver-chloride salt. Microleakage with infection and galvanic reaction are possible hypotheses as to the reason for the degradation of the silver point. Although other reports have demonstrated corrosion of silver points, this method of presentation appears unique.

Fixed prostheses in the treatment of tooth wear

The restorative implications of tooth wear are often complicated by the age of the patient, the destructive nature and aesthetic compromise of conventional fixed restorations and the lack of inter-occlusal space. This paper focuses on the fixed prosthetic treatment options for such patients and the utilisation of fixed restorations to create inter-occlusal space.

Adult acute leukaemia--a retrospective study of 66 consecutive patients

BACKGROUND

Advances in therapy and supportive care have improved the outlook for many patients with acute leukaemia, however elderly patients have increased treatment-related toxicity and shorter survival. Most clinical trials have selected patient populations with young median ages and it is therefore difficult to apply results to the general population where the majority of patients presenting with acute leukaemia are over 60 years. There is little information in the literature guiding appropriate treatment of these patients.

AIMS

To determine the relationship between age, treatment received, and outcome in patients presenting with acute leukaemia.

METHODS

A retrospective analysis was performed on all patients presenting to Prince Henry's Hospital and Monash Medical Centre with acute myeloid leukaemia (AML) or acute lymphocytic leukaemia (ALL) during a five year period.

RESULTS

Sixty-six patients (51-AML, 15-ALL) presented with acute leukaemia between March 1989 and April 1994. Median patient age was 63 years; 32% of patients received supportive therapy only; 86% of patients with ALL and 58% of patients with AML commencing remission-induction chemotherapy entered a complete remission. Median survival for patients receiving only supportive therapy was three months. Median survival in patients under 55 years was almost twice as long as patients over 55 years receiving similar treatment (AML-eight vs four months p = 0.023; ALL-3.5 vs seven months p = 0.029).

CONCLUSIONS

Median survival for acute leukaemia is inversely proportional to age. Applying results from selected series to elderly patients with acute leukaemia is inappropriate.

Wear now? An update on the etiology of tooth wear

Tooth wear is an ever-increasing problem, and younger patients are particularly at risk. The problem is likely to continue as patients' demands and expectations rise and as more natural teeth are retained into old age. The etiology of tooth wear is reviewed, with emphasis on those factors that appear to be major contributors to the problem at the moment. The clinical appearance of tooth wear is also discussed. It would appear that erosive factors are a significant cause of tooth wear. The prominence of acidic damage of tooth tissue is probably a reflection of society's concern with healthy eating and appearance.

The single unit, single retainer, cantilever resin-bonded bridge

Resin-bonded restorations have many advantages over conventional alternatives. Advances in adhesive technology together with a better understanding of the clinical function of such restorations have allowed resin-bonded bridges to play an important role in everyday clinical practice. This paper highlights the role and importance of the single abutment, single pontic cantilever resin-bonded bridge. Clinical experience might suggest that the cantilever design offers a viable alternative to other designs. Furthermore, the paper suggests that when cantilever resin-bonded bridges fail initially, re-bond often leads to predictable long-term success. Factors such as patient selection, abutment preparation, retainer design and the aesthetic limitations of resin-bonded bridges are also discussed. The authors can claim that further clinical studies are necessary to identify exactly what factors influence the success of cantilever and other resin-bonded designs.

Oral complications associated with sickle cell anemia: a review and case report

Sickle cell anemia is a multisystem disease that can affect the oral region. This article reviews previously reported oral complications associated with this disease and describes the cause of these problems. A case history describes a patient with multiple oral problems after a sickle cell crisis. The diagnostic and management problems of this case are highlighted. The need for a multidisciplinary approach to the care of these patients is emphasized.

Margin design for porcelain fused to metal restorations which extend onto the root

A 90 degree shoulder is probably the most commonly used margin design for porcelain fused to metal (PFM) restorations. However, this design requires the removal of a significant amount of tooth tissue to provide a predictable restoration. This increases the risk of irreversible damage to the pulp, particularly if little tooth tissue is present, for example on exposed roots. In these situations more conservative designs, such as the 135 degree shoulder or deep chamfer, should be considered. Ideally these designs should be used with an all-metal margin since this is associated with the most predictable marginal seal. Where an all metal margin is aesthetically unacceptable a porcelain butt or subgingival margin can be considered. Newer techniques, such as resin bonded crowns, which minimise tooth destruction and provide acceptable aesthetics may be a viable alternative to traditional PFM restorations. Unfortunately, these newer techniques have not been evaluated long-term.

Restoration of a worn dentition using a double-veneer technique

Restoration of dentitions affected by tooth surface loss has been a problem to the dental profession for many years. This problem is likely to increase as the population ages and retains more teeth into old age. This article describes a method of restoring teeth with non-carious loss of tooth tissue whilst conserving the remaining tooth tissue.

Sickle cell disease: a diagnostic dilemma

The case history is described of a patient with sickle cell anaemia who developed a unilateral infarct of the mandible following a sickle cell crisis. The interruption of the blood supply resulted in an anaesthesia of the inferior dental nerve and pulpal necrosis of otherwise sound premolar and molar teeth. The diagnostic and management difficulties of the case are discussed, and recommendations are made for treatment of such patients in light of the problems encountered.

Endodontic failure--a problem from top to bottom

Endodontically treated teeth are susceptible to bacterial contamination through exposure to oral fluids. It is crucial, therefore, that restorations placed during and after root canal therapy protect the root canal from oral contamination. This paper highlights the clinical steps necessary to reduce the risk of contamination in root-filled teeth.

Multiple agminated Spitz nevi: report of two cases and review of the literature

Spitz nevus is most commonly a benign solitary lesion. Multiple lesions arranged in clusters (agminated) are very rare. Malignant degeneration has not been reported. Although spontaneous involution may occur, the nevi are frequently treated by surgical excision. We describe two preschool girls with multiple agminated Spitz nevi, and review the current world literature on multiple Spitz nevi.

Case report: the use of indirect composite for the management of extensive erosion

Erosive tooth surface loss due to acidic soft-drinks has been well documented. Unfortunately, the erosive danger, especially to young patients, of low calorie beverages seems less well appreciated. A clinical case is reported to highlight the problems that can occur with excessive exposure to such beverages. A method of restoring the damaged dentition using indirect composite is described. It is concluded that indirect composite may be particularly suited for the restoration of eroded dentitions, especially in young patients where aesthetics and repairability are important. Further clinical studies are necessary to assess the performance of these and other materials currently used in the management of erosive tooth wear.

Identification and immediate management of the oral changes associated with eating disorders

Oral changes are often the first indication that an eating disorder is present. Although the effect of acid regurgitation on the teeth is well appreciated, other factors may also be involved. This article highlights the changes that may be observed in patients with eating disorders, together with the possible aetiological causes.

The aetiology and management of localized anterior tooth wear in the young adult

This article reviews the aetiology and clinical features of the increasingly common problem of localized loss of anterior tooth tissue in the young adult. The management of the problem is highlighted, with emphasis placed on preservation of the tooth structure and the use of modern materials and techniques.

Consistent benefits for the system designer and the end-user

Command languages which are internally consistent are said to be easier to learn. The level of consistency - or degree of user complexity - of any command language is usually defined using one of a number of formal grammars, and yet consistency need not be so rigorously defined. It is proposed that diagrams can provide a suitable meta-language with which to illustrate the consistent properties of any command set; and a particular type of diagram - the 'command wheel' - is described. Command wheels offer a number of advantages over formal specifications, being simple to construct and allowing more discretion in the design process. In a study of word-processor users, it was found that properties of command wheels allowed the accurate prediction of user's behaviour, both in terms of their on-line performance, and their subsequent ability to recall commands.

Presuturing--a new technique for closing large skin defects: clinical and experimental studies

We have developed a new technique termed presuturing for aiding in the closure of large skin defects which may have otherwise required a skin graft or flap. This technique is based on biomechanical properties of skin (creep, stress relaxation) which allow skin to stretch beyond its inherent extensibility. Presuturing is performed under local anesthesia and consists of plicating intact skin over the area of planned excision the night prior to operation. Experimental studies in a pig model showed the decrease in force required to close a standard-sized wound to be 40.1 percent less than control (p less than 0.001). Fourteen patients who underwent wide excision of skin lesions had their wounds presutured. All but one wound could be closed primarily without undermining. Presuturing seems to be an easy and clinically useful technique in aiding the primary closure of large defects.

Hybrid biphenotypic acute leukemia with extreme hypodiploidy

A patient diagnosed as having acute lymphoblastic leukemia (L2) relapsed 4 months later and was found to have morphologic and immunologic evidence of a biphenotypic hybrid acute leukemia. Chromosome analysis at relapse showed two abnormal clones, one with marked hypodiploidy and the other with exactly double the hypodiploid clone. It is considered that this is an example of a hybrid lymphoblastic/nonlymphoblastic leukemia with unique karyotype.

The development of word recognition processes

To observe the course of the development of automatic processes in word recognition, two experiments were performed in which a distracting word interacted with a target stimulus. In Expt 1 the subjects named a simple line drawing, and in Expt 2 they named a word appearing in a rectangle. The distracting word (i) was a semantic associate of the target stimulus, (ii) was graphemically similar to the name of the target, (iii) was phonemically similar to the name of the target, (iv) was unrelated in meaning, orthography and phonology, or (v) was replaced with an unpronounceable letter string. Three groups of subjects were tested. Skilled adult readers were compared with two groups of children. Matched groups of children were used, with similar ages (9-12 years old) and non-verbal spatial abilities, but dissimilar reading ages. All groups of subjects showed semantic interference and graphemic priming from the distractor word in Expt 1, and the children showed phonemic priming. In Expt 2, only the poor readers showed semantic interference, and no groups showed graphemic or phonemic effects. The sensitivity of the poor readers to the distractors indicates that the semantic, graphemic and phonemic codes of words are generated by these subjects, and that the difference in reading age between them and the good readers can be attributed to post-lexical processes such as text integration and articulatory planning and execution.

Performance of an annular resonator with a polarizer in the annular leg

Experiments were performed on a CO(2) laser with an annular resonator. The objective of these experiments was to control the polarization in an annular laser and to verify computer code predictions. A Mylar pellicle was placed in the annular leg, and its angular orientation with respect to the optical axis was varied. The pellicle had different transmittances for horizontal and vertical polarizations and also had stress-induced birefringence. At small angles of incidence in the pellicle, the birefringence dominated, and the output had a complicated nature. However, at large angles of incidence, the transmittance difference forced the laser into a well-defined mode for which the near field was horizontally polarized at the top and bottom and the two sides and vertically polarized at intermediate locations. The experimental results were in good agreement with the computer code calculations.

Robbing Peter to pay Paul

Cutbacks in the health service are already affecting recruitment. Employing authorities are facing the problem of reducing expenditure and this will, inevitably lead to a reappraisal of decisions to employ locums. Peter Briggs, area medical officer for Hillingdon, discusses the implications and looks at the situation in the London area.

Stimulus intensity and foreperiod effects in intersensory facilitation

Intersensory facilitation refers to the more rapid reaction time (RT) to a target in one modality and an accessory stimulus in a different modality compared to a RT to the target alone. Prior studies suggest two processes contribute to the phenomenon, termed the preparatory state and energy integration which refer to the action of accessory stimulation in providing forewarning and intensifying the reaction signal, respectively. Experiment I factorially varied foreperiod duration, light (target) intensity and tone (accessory) intensity in a discriminative RT task. The results were that foreperiod (preparatory state) and intensity (energy integration) effects were additive, implying that they affected separate processing stages. Accessory stimulus intensity affected false alarm rate on catch trials. This suggests that energy integration involves a form of response bias (increased likelihood of responding) and not facilitation (more rapid information processing). Experiment II indicated that comparable energy integration effects obtain with tone as target and light as accessory, as well as vice versa. The findings further indicated that RT to a bisensory pairing is more rapid when attention is directed to the more potent member of the pair.