Precision medicine for psychotic disorders: objective assessment, risk prediction, and pharmacogenomics

Psychosis occurs inside the brain, but may have external manifestations (peripheral molecular biomarkers, behaviors) that can be objectively and quantitatively measured. Blood biomarkers that track core psychotic manifestations such as hallucinations and delusions could provide a window into the biology of psychosis, as well as help with diagnosis and treatment. We endeavored to identify objective blood gene expression biomarkers for hallucinations and delusions, using a stepwise discovery, prioritization, validation, and testing in independent cohorts design. We were successful in identifying biomarkers that were predictive of high hallucinations and of high delusions states, and of future psychiatric hospitalizations related to them, more so when personalized by gender and diagnosis. Top biomarkers for hallucinations that survived discovery, prioritization, validation and testing include PPP3CB, DLG1, ENPP2, ZEB2, and RTN4. Top biomarkers for delusions include AUTS2, MACROD2, NR4A2, PDE4D, PDP1, and RORA. The top biological pathways uncovered by our work are glutamatergic synapse for hallucinations, as well as Rap1 signaling for delusions. Some of the biomarkers are targets of existing drugs, of potential utility in pharmacogenomics approaches (matching patients to medications, monitoring response to treatment). The top biomarkers gene expression signatures through bioinformatic analyses suggested a prioritization of existing medications such as clozapine and risperidone, as well as of lithium, fluoxetine, valproate, and the nutraceuticals omega-3 fatty acids and magnesium. Finally, we provide an example of how a personalized laboratory report for doctors would look. Overall, our work provides advances for the improved diagnosis and treatment for schizophrenia and other psychotic disorders.

Surgical vs Non-surgical interventions for distal radius fractures: a quantitative analysis of Patient-Rated Wrist Evaluation measures

Trials to assess differences in PRWE (Patient Related Wrist Evaluation) over time, for both surgical and non-surgical interventions post DRFs (distal radius fractures) are rare. The DASH (Disabilities of the Arm, Shoulder and Hand) questionnaire has been shown to be improved by a greater margin in the medium term for surgical interventions, than non surgical interventions. However, a study found that PRWE can be considered superior to the DASH questionnaire for DRFs, due to greater specificity to wrist pain and function. Conflicting data makes it difficult to determine surgical vs non-surgical superiority for DRF's over time with PRWE as a recovery metric. PubMed and Cochrane were searched for randomised controlled trials up to 31.8.23, reporting PRWE over 3, and 12 months. Data was extracted by 2 researchers. The differences in PRWE over time post surgical and non-surgical interventions was assessed using unpaired T testing. 1226 records were screened. 4 studies enrolling 817 participants met the eligibility criteria and were analysed. Significantly lower PRWE in surgical intervention has been identified at the 3 month mark (p<0.001). There was greater significant change in non-surgical intervention between months 3 and 12 (p<0.001). Change in PRWE over time may be a good indicator of functional outcomes in DRFs post surgical or non-surgical interventions. This could inform future clinical trial design and surgical decision-making. Further work is required to design even more user-friendly and digital patient- reported outcomes specifically for DRFs.

Towards precision medicine for anxiety disorders: objective assessment, risk prediction, pharmacogenomics, and repurposed drugs

Anxiety disorders are increasingly prevalent, affect people's ability to do things, and decrease quality of life. Due to lack of objective tests, they are underdiagnosed and sub-optimally treated, resulting in adverse life events and/or addictions. We endeavored to discover blood biomarkers for anxiety, using a four-step approach. First, we used a longitudinal within-subject design in individuals with psychiatric disorders to discover blood gene expression changes between self-reported low anxiety and high anxiety states. Second, we prioritized the list of candidate biomarkers with a Convergent Functional Genomics approach using other evidence in the field. Third, we validated our top biomarkers from discovery and prioritization in an independent cohort of psychiatric subjects with clinically severe anxiety. Fourth, we tested these candidate biomarkers for clinical utility, i.e. ability to predict anxiety severity state, and future clinical worsening (hospitalizations with anxiety as a contributory cause), in another independent cohort of psychiatric subjects. We showed increased accuracy of individual biomarkers with a personalized approach, by gender and diagnosis, particularly in women. The biomarkers with the best overall evidence were GAD1, NTRK3, ADRA2A, FZD10, GRK4, and SLC6A4. Finally, we identified which of our biomarkers are targets of existing drugs (such as a valproate, omega-3 fatty acids, fluoxetine, lithium, sertraline, benzodiazepines, and ketamine), and thus can be used to match patients to medications and measure response to treatment. We also used our biomarker gene expression signature to identify drugs that could be repurposed for treating anxiety, such as estradiol, pirenperone, loperamide, and disopyramide. Given the detrimental impact of untreated anxiety, the current lack of objective measures to guide treatment, and the addiction potential of existing benzodiazepines-based anxiety medications, there is a urgent need for more precise and personalized approaches like the one we developed.

Risk factors for outbreaks caused by variant strain of Newcastle disease on environmentally controlled broiler chicken farms in Lahore, Pakistan

Newcastle disease (ND) is a frequently reported disease in poultry among both vaccinated and non-vaccinated flocks in Pakistan. During 2011-2012 poultry industry in Punjab, mainly in Lahore region, faced fatal outbreaks of ND caused by a variant strain. An analytical study was conducted during outbreak period in Lahore region. A total of 114 environmentally controlled farms were selected with the help of convenient sampling method. A questionnaire was designed about the potential risk factors associated with the spread of ND outbreak. The bivariate relationships between ND status and independent variables were investigated by applying the Chi-square and Fisher's exact test. Multivariable logistic model was used to estimate the effect of each studied variable on the outcome by adjusting the other variables in the model. The variables which showed an association with ND outbreaks at commercial poultry farms were improper method for dead birds disposal (OR=4.96; 95% CI 1.63-15.12), use of same feed transporting vehicle at multiple poultry farms (OR=4.92; 95% CI 1.58-15.33), farm to farm distance of less than 1 km (OR=9.32; 95% CI(1.19-73.12), number of sheds at one farm (OR=2.31; 95% CI 0.93-5.69), labor type (OR=2.72; 95% CI 0.83-8.88) and biosecurity (OR= 4.47; 95% CI 0.56-35.66).

Tumor-derived osteopontin drives the resident fibroblast to myofibroblast differentiation through Twist1 to promote breast cancer progression

Tumor-stroma interactions are important determinants for the disease course in cancer. While stromal influence has been known to often play a tumor-promoting role, incomplete mechanistic insight into this phenomenon has prevented its therapeutic targeting. Stromal fibroblasts can be activated by tumor cells to differentiate into cancer-associated fibroblasts (CAFs), that exhibit the traits of myofibroblasts, and in turn, they increase cancer aggressiveness. Here, we report the crosstalk between the cancer cells and stromal fibroblasts that leads to tumor progression. The process is initiated by secretion of a chemokine like protein, osteopontin (OPN) from the cancer cells that differentiates the fibroblasts to myofibroblasts. Tumor-derived OPN achieves this transition by engaging CD44 and αvβ3 integrins on the fibroblast surface, which mediates signaling via Akt and ERK to induce Twist1-dependent gene expression. The OPN-driven CAFs then secrete CXCL12, which in turn triggers epithelial to mesenchymal transition (EMT) in the tumor cells. OPN, produced by the cancer cells, and CXCL12, secreted by activated fibroblasts, are necessary and sufficient to perpetuate the crosstalk. Knocking out OPN in carcinogen-induced mammary tumors or knocking down OPN in cancer cells and fibroblast co-implanted xenografts abrogates myofibroblast differentiation, Twist1, and CXCL12 expression. OPN expression is correlated with CAF-specific gene signature as shown by breast tumor tissue microarray consisting of 100 patient specimens. Bioinformatics analyses have confirmed that the expression of OPN is significantly correlated with the expression of myofibroblast-specific markers as demonstrated in human breast carcinoma dataset of 2509 patients. Our findings describe OPN and CXCL12 act as compelling targets to curb the tumor-promoting features of the stromal components and further suggested that OPN-regulated CXCL12 network might act as potential therapeutic target for the management of CAF-mediated breast cancer progression.

Correlative Study of Cytological Features in Grading of Invasive Breast Carcinoma

Context:

Fine-needle aspiration cytology (FNAC) is a proven diagnostic technique for establishing the benign or malignant character of breast lesions. Several cytological grading systems have been proposed for grading of carcinoma breast, with results similar to histologic grades.

Aims:

This study sought to evaluate the prognostic value of FNAC in invasive ductal carcinoma of breast by correlating it with histological grade.

Settings and Design:

Tertiary care hospital, retrospective analytical study.

Patients and Methods:

One hundred and fifty cases of breast carcinoma that underwent modified radical mastectomy consequent to an FNAC diagnosis were included in the study. Robinson's grading system and Elston–Ellis modification of Scarff–Bloom–Richardson grading system were used to assign cytologic and histologic grades, respectively.

Statistical Analysis:

The cytological grades were correlated with the histological grades using χ²-test and Spearman's rank correlation coefficient. The individual features of the cytological grades were correlated with the histological grades using Kappa coefficient and χ²-test. Values were considered significant at P < 0.05.

Results:

A statistically significant association was observed between cytologic and histologic grades (r = 0.97; P < 0.01) with sensitivity and specificity, respectively, of 100% and 93.95% for cytological grade 1, 100% and 100% for cytological grade 2 and 100% and 100% for cytological grade 3. Also, a positive correlation was found between each feature of the cytologic grade and the histologic grade (P < 0.05). Among these, a better correlation was demonstrated by cytological features like cell uniformity (Kappa coefficient = 0.50) and appearance of nucleoli (Kappa coefficient = 0.52).

Conclusions:

Robinson's cytologic grading system is a reliable grading method on FNAC smears of cases of carcinoma breast. It correlates well with Elston–Ellis modification of Scarff–Bloom–Richardson grade in invasive ductal carcinoma of breast.

Convection enhanced delivery of panobinostat (LBH589)-loaded pluronic nano-micelles prolongs survival in the F98 rat glioma model

Background

The pan-histone deacetylase inhibitor panobinostat is a potential therapy for malignant glioma, but it is water insoluble and does not cross the blood–brain barrier when administered systemically. In this article, we describe the in vitro and in vivo efficacy of a novel water-soluble nano-micellar formulation of panobinostat designed for administration by convection enhanced delivery (CED).

Materials and methods

The in vitro efficacy of panobinostat-loaded nano-micelles against rat F98, human U87-MG and M059K glioma cells and against patient-derived glioma stem cells was measured using a cell viability assay. Nano-micelle distribution in rat brain was analyzed following acute CED using rhodamine-labeled nano-micelles, and toxicity was assayed using immunofluorescent microscopy and synaptophysin enzyme-linked immunosorbent assay. We compared the survival of the bioluminescent syngenic F98/Fischer344 rat glioblastoma model treated by acute CED of panobinostat-loaded nano-micelles with that of untreated and vehicle-only-treated controls.

Results

Nano-micellar panobinostat is cytotoxic to rat and human glioma cells in vitro in a dose-dependent manner following short-time exposure to drug. Fluorescent rhodamine-labelled nano-micelles distribute with a volume of infusion/volume of distribution (Vi/Vd) ratio of four and five respectively after administration by CED. Administration was not associated with any toxicity when compared to controls. CED of panobinostat-loaded nano-micelles was associated with significantly improved survival when compared to controls (n=8 per group; log-rank test, P<0.001). One hundred percent of treated animals survived the 60-day experimental period and had tumour response on post-mortem histological examination.

Conclusion

CED of nano-micellar panobinostat represents a potential novel therapeutic option for malignant glioma and warrants translation into the clinic.

Provincial elections and timing of cancer drug funding

BACKGROUND

Concerns have been raised about the potential influence of political pressures on drug funding decisions. We evaluated the temporal relationship between cancer drug funding and provincial elections in 9 Canadian provinces.

METHODS

New indications for cancer drugs between January 2003 and December 2012 were identified, and the dates of official provincial funding dates and election dates between 1 January 2003 and 31 December 2014 were retrieved. The probability of drug funding announcements in the 60-day period preceding a provincial election was evaluated using binomial probability distribution analysis.

RESULTS

Data from 9 provinces (all Canadian provinces except Quebec) were available. During the period of interest, 69 new indications for 39 individual drugs were identified. Variation in the availability of funding dates was identified. At the time of data collection, 2 provinces did not have data available for all 69 indications. For the 9 provinces, the number of funded indications during the 60-day period preceding an election ranged from 0 to 3; however, no differences in the proportion of indications funded pre-election were identified. Additional analyses also failed to demonstrate any significant associations with the 90-day period before an election, or the 60- and 90-day periods after an election.

CONCLUSIONS

We observed no clear temporal relationship between provincial election dates and funding decisions in this recent Canadian sample of new indications for cancer drugs.

Respiratory-aspirated 35-mm hairpin successfully retrieved with a Teflon® snare system under fluoroscopic guidance via a split endotracheal tube: a useful technique in cases of failed extraction by bronchoscopy and avoiding the need for a thoracotomy

Respiratory foreign body aspiration (FBA) is a common global health problem requiring prompt recognition and early treatment to prevent potentially fatal complications. The majority of FBAs are due to organic objects and treatment is usually via either endoscopic or surgical extraction. FBA of a straight hairpin has been described as a unique entity in the literature, occurring most commonly in females, particularly during adolescence. In the process of inserting hairpins, the pins will typically be between the teeth with the head tilted backwards, while tying their hair with both hands. This position increases the risk of aspiration, particularly if there is any sudden coughing or laughing. To our knowledge, this is the first case report of a 35-mm straight metallic hairpin foreign body that has been successfully retrieved by a radiological snare system under fluoroscopic guidance. This was achieved with the use of a split endotracheal tube, and therefore avoided the need for a thoracotomy in an adolescent female patient.

Controlling soot formation with filtered EGR for diesel and biodiesel fuelled engines

Although exhaust gas recirculation (EGR) is an effective strategy for controlling the levels of nitrogen oxides (NO(X)) emitted from a diesel engine, the full potential of EGR in NO(X)/PM trade-off and engine performance (i.e., fuel economy) has not fully been exploited. Significant work into the cause and control of particulate matter (PM) has been made over the past decade with new cleaner fuels and after-treatment devices emerging to comply with the current and forthcoming emission regulations. In earlier work, we demonstrated that engine operation with oxygenated fuels (e.g., biodiesel) reduces the PM emissions and extends the engine tolerance to EGR before it reaches smoke-limited conditions. The same result has also been reported when high cetane number fuels such as gas-to-liquid (GTL) are used. To further our understanding of the relationship between EGR and PM formation, a diesel particulate filter (DPF) was integrated into the EGR loop to filter the recirculated soot particulates. The control of the soot recirculation penalty through filtered EGR (FEGR) resulted in a 50% engine-out soot reduction, thus showing the possibility of extending the maximum EGR limit or being able to run at the same level of EGR with an improved NO(X)/soot trade-off.

Combined pedunculopontine-subthalamic stimulation in Parkinson disease

OBJECTIVE

To assess the effect of deep brain stimulation (DBS) in the pedunculopontine nucleus (PPN) and caudal zona incerta (cZi)-both separately and in combination-on motor symptoms and regional cerebral blood flow (rCBF) in patients with Parkinson disease (PD).

METHODS

Four patients with bilateral cZi and PPN DBS electrodes were rated with the Unified Parkinson's Disease Rating Scale motor subscale (UPDRS-III) when taking and withdrawn from medication. A block of 16 [(15)O]-H(2)O PET resting measurements of rCBF were performed in 4 different states with patients withdrawn from medication: 1) no stimulation, 2) cZi stimulation alone, 3) PPN stimulation alone, 4) combined PPN/cZi stimulation.

RESULTS

When patients were medicated, combined PPN/cZi stimulation produced a statistically significant improvement in UPDRS-III score compared to cZi stimulation alone. In the "off" medication state, the clinical effect of combined stimulation was not significantly different from that induced by cZi stimulation alone. Concomitant PPN/cZi stimulation had a cumulative effect on levels of rCBF, effectively combining subcortical and cortical changes induced by stimulation of either target in isolation.

CONCLUSIONS

These findings suggest that concomitant low frequency stimulation of PPN and cZi regions induces additive brain activation changes and provides improved control of PD symptoms when medicated.

CLASSIFICATION OF EVIDENCE

This study provides Class IV evidence that concomitant low frequency stimulation of PPN and cZI improves motor symptoms in patients with PD on dopamine replacement. It provides Class III evidence that concomitant low frequency stimulation of PPN and cZi induces additive rCBF changes in motor areas of brain.

Clonality assessment of lymphoproliferative lesions using the polymerase chain reaction: an analysis of two methods

BACKGROUND

Lymphoid malignancies are a heterogeneous group of disorders which may be difficult to differentiate from reactive proliferations even after immunohistochemistry. Polymerase chain reaction (PCR) is believed to be a good adjunct tool for diagnosis.

MATERIALS AND METHODS

We examined 24 cases of neoplastic and non-neoplastic lymphoproliferative lesions in this study and evaluated the PCR as an additional tool in the confirmation of the diagnosis. Two different PCR methodologies were evaluated.

RESULTS

In the evaluation of the T-cell PCR, it was seen that the correlation using both the commercial kits and the custom-synthesized primers was highly significant at a P value of <0.05. In the evaluation of the B-cell PCR, it was seen that the correlation using both the commercial kits and the custom-synthesized primers was not significant using either method (P > 0.05).

CONCLUSIONS

Both the methods showed an excellent concordance for T-cell γ gene rearrangements, However, the same was not seen in the B-cell receptor rearrangements. This may be because of the small sample size or the inability of consensus V primers to recognize complementary DNA sequences in all of the V segments.

Analysis of foramen ovale with special emphasis on pterygoalar bar and pterygoalar foramen

The foramen ovale is of great surgical and diagnostic importance in procedures like percutaneous trigeminal rhizotomy for trigeminal neuralgia, transfacial fine needle aspiration technique in perineural spread of tumour, and electroencephalographic analysis. This study presents the anatomic variations in dimensions, appearance, number of foramen ovale (FO), and presence of pterygoalar bar and pterygoalar foramen. For the present study ninety dry adult human skulls were utilised. Anterioposterior (length) and transverse (width) diameters of FO were measured, and the presence of pterygoalar bar and foramen were observed. The most common shape of FO observed was like a figure 'D'. The ranges of anteroposterior diameter of the right and left FO were 8.5-4.5 mm and 10-3 mm, respectively. The mean length of the right FO was 6.60 mm while that of the left FO was 6.26 mm. The ranges of transverse diameter (width) of both right and left foramen were 2.5-6 mm and 2-5 mm, respectively. The mean transverse diameter of the right FO was 3.70 mm and that of left was 3.34 mm. Bony spur in FO was seen in 6.66% of cases. A complete pterygoalar bar and foramen were observed in seven cases unilaterally, and in one case it was bilateral. Anteroposterior and transverse diameters of right FO were greater than left. Anatomical understanding, including the size, shape of FO, and presence of pterygoalar bar, has immense surgical and diagnostic importance.

A role for endosomal proteins in alphavirus dissemination in mosquitoes

Little is known about endosomal pathway proteins involved in arthropod-borne virus (arbovirus) assembly and cell-to-cell spread in vector mosquitoes. UNC93A and synaptic vesicle-2 (SV2) proteins are involved in intracellular transport in mammals. They show amino acid sequence conservation from mosquitoes to humans, and their transcripts are highly enriched in Aedes aegypti during arbovirus infection. Transient gene silencing of SV2 or UNC93A in mosquitoes infected with the recombinant alphavirus Sindbis MRE16-enhanced green fluorescent protein (SINV; family Togaviridae) resulted in the accumulation of viral positive- and negative-strand RNA, congregation of virus envelope antigen in intracellular networks, and reduced virus dissemination outside of the midgut. Further, UNC93A silencing, but not SV2 silencing, resulted in a 10-fold reduction in viral titres at 4 days post-infection. Together, these data support a role for UNC93A and SV2 in virus assembly or budding. Cis-regulatory elements (CREs) were identified at the 5'-ends of genes from the original data set in which SV2 and UNC93A were identified. Common CREs at the 5'-end genomic regions of a subset of enriched transcripts support the hypothesis that UNC93A transcription may be co-regulated with that of other ion transport and endosomal trafficking proteins.

Computerised Tomography Features in Gliomas

106 cases of intracranial tumours were evaluated, out of which 42 cases (39.6%) were histologically confirmed as gliomas. Computerised tomography (CT) imaging characteristics of glioma were studied with respect to morphology and contrast enhancement to find a possible correlation between CT appearance and the grade of malignancy. It was found that there is a range of patterns both before and after intravenous contrast, which allows an assessment of grading of the tumour with a fair degree of reliability.

A robust MRI-compatible system to facilitate highly accurate stereotactic administration of therapeutic agents to targets within the brain of a large animal model

Achieving accurate intracranial electrode or catheter placement is critical in clinical practice in order to maximise the efficacy of deep brain stimulation and drug delivery respectively as well as to minimise side-effects. We have developed a highly accurate and robust method for MRI-guided, stereotactic delivery of catheters and electrodes to deep target structures in the brain of pigs. This study outlines the development of this equipment and animal model. Specifically this system enables reliable head immobilisation, acquisition of high-resolution MR images, precise co-registration of MRI and stereotactic spaces and overall rigidity to facilitate accurate burr hole-generation and catheter implantation.

To demonstrate the utility of this system, in this study a total of twelve catheters were implanted into the putamen of six Large White Landrace pigs. All implants were accurately placed into the putamen. Target accuracy had a mean Euclidean distance of 0.623 mm (standard deviation of 0.33 mm). This method has allowed us to accurately insert fine cannulae, suitable for the administration of therapeutic agents by convection-enhanced delivery (CED), into the brain of pigs. This study provides summary evidence of a robust system for catheter implantation into the brain of a large animal model. We are currently using this stereotactic system, implantation procedure and animal model to develop catheter-based drug delivery systems that will be translated into human clinical trials, as well as to model the distribution of therapeutic agents administered by CED over large volumes of brain.

Dystonia in neurodegeneration with brain iron accumulation: outcome of bilateral pallidal stimulation

Neurodegeneration with brain iron accumulation encompasses a heterogeneous group of rare neurodegenerative disorders that are characterized by iron accumulation in the brain. Severe generalized dystonia is frequently a prominent symptom and can be very disabling, causing gait impairment, difficulty with speech and swallowing, pain and respiratory distress. Several case reports and one case series have been published concerning therapeutic outcome of pallidal deep brain stimulation in dystonia caused by neurodegeneration with brain iron degeneration, reporting mostly favourable outcomes. However, with case studies, there may be a reporting bias towards favourable outcome. Thus, we undertook this multi-centre retrospective study to gather worldwide experiences with bilateral pallidal deep brain stimulation in patients with neurodegeneration with brain iron accumulation. A total of 16 centres contributed 23 patients with confirmed neurodegeneration with brain iron accumulation and bilateral pallidal deep brain stimulation. Patient details including gender, age at onset, age at operation, genetic status, magnetic resonance imaging status, history and clinical findings were requested. Data on severity of dystonia (Burke Fahn Marsden Dystonia Rating Scale-Motor Scale, Barry Albright Dystonia Scale), disability (Burke Fahn Marsden Dystonia Rating Scale-Disability Scale), quality of life (subjective global rating from 1 to 10 obtained retrospectively from patient and caregiver) as well as data on supportive therapy, concurrent pharmacotherapy, stimulation settings, adverse events and side effects were collected. Data were collected once preoperatively and at 2-6 and 9-15 months postoperatively. The primary outcome measure was change in severity of dystonia. The mean improvement in severity of dystonia was 28.5% at 2-6 months and 25.7% at 9-15 months. At 9-15 months postoperatively, 66.7% of patients showed an improvement of 20% or more in severity of dystonia, and 31.3% showed an improvement of 20% or more in disability. Global quality of life ratings showed a median improvement of 83.3% at 9-15 months. Severity of dystonia preoperatively and disease duration predicted improvement in severity of dystonia at 2-6 months; this failed to reach significance at 9-15 months. The study confirms that dystonia in neurodegeneration with brain iron accumulation improves with bilateral pallidal deep brain stimulation, although this improvement is not as great as the benefit reported in patients with primary generalized dystonias or some other secondary dystonias. The patients with more severe dystonia seem to benefit more. A well-controlled, multi-centre prospective study is necessary to enable evidence-based therapeutic decisions and better predict therapeutic outcomes.

Congenital subtalar dislocation--a case report

Congenital dislocation of the subtalar joint is one of the rarest forms of presentation of a calcaneo-valgus foot. We report the second case of this type published; an 18-month female child aged was seen with calcaneo-valgus deformity of left foot since birth. She was walking over the medial malleolus and medial border of foot. Radiographs and 3D CT scan of the left foot confirmed the diagnosis of a congenital subtalar dislocation. Surgical correction was achieved through a posterolateral incision, and the reduced joint was fixed with a k-wires for 6 weeks; the foot was immobilized in below knee cast for another 6 weeks, and an ankle foot orthosis was used for another 3 years. At 3 years post-surgical follow up, the child has a plantigrade foot with no functional impairment. Follow up radiographs and 3D CT scan confirmed the maintenance of well aligned talo-calcaneal joint. This type of dislocation should be considered in the differential diagnosis of calcaneo-valgus foot; a clear understanding of the pathology, a precise operative reduction, and long-term use of orthosis results in a favourable outcome.

Endovascular aortic repair: the experience of two tertiary institutions in Singapore

INTRODUCTION

Endovascular aortic repair (EVAR) has gained prominence as a means of treating aortic disease, with lower perioperative morbidity and mortality compared to open surgery. This article aimed to describe the experience of two tertiary hospitals in a Southeast Asian population.

METHODS

A retrospective review of 100 consecutive patients undergoing EVAR in two hospitals in Singapore was conducted. This included patients undergoing elective as well as emergency repair.

RESULTS

The mean duration of follow-up was 31.8 months. The mean aneurysm size was 6.3 cm and the mean length of stay was 12.1 days. 64 percent of the patients were of American Society of Anesthesiologists class III or above. The deployment success was 98 percent. Major complications (acute myocardial infarction, pneumonia, cerebrovascular accidents, renal failure, colonic infarction and spinal cord infarction) occurred in 18 patients. Perioperative mortality occurred in six percent of cases. The endoleak rate was 28 percent. Both patients with colonic infarction had a single patent internal iliac artery post-procedure, and end-stage renal failure.

CONCLUSION

Our results are comparable to published experiences in aortic stenting. Our population possibly had a higher incidence of short common iliac arteries. Revascularisation of internal iliac arteries should be considered for patients with end-stage renal failure and a single patent internal iliac artery.

Published randomized controlled trials of drug therapy for dementia often lack complete data on harm

OBJECTIVE

The objective of the study was to determine the extent to which published randomized controlled trials (RCTs) report data on harm.

STUDY DESIGN AND SETTING

A systematic search strategy was used to identify RCTs published between 1996 and 2005 on the use of cholinesterase inhibitors or atypical antipsychotics in patients with dementia. A structured abstraction form was used to determine if data on mortality or serious adverse events were reported and if the articles followed Consolidated Standards of Reporting Trials format for reporting harm.

RESULTS

Thirty-three RCTs were identified (27 on cholinesterase inhibitors and 6 on atypical antipsychotics). Nineteen trials (58%) had explicit data on mortality and only four (12%) reported regulatory-agency-defined serious adverse events. Most abstracts (31, 94%) stated that harm was studied but few studies (9, 27%) provided a clear definition of the measures of harm.

CONCLUSIONS

Although most published RCTs state that they examine harm, many failed to provide data on mortality and most lacked clear definitions or detailed analyses of harm. Better reporting of harm would provide timely and important information that could help physicians and the public to make more informed decisions.

Induction of parkinsonian resting tremor by stimulation of the caudal zona incerta nucleus: a clinical study

INTRODUCTION

We hypothesise that parkinsonian tremor arises when the caudal zona incerta (cZI) and subthalamic nucleus (STN) are deprived of dopamine and become increasingly responsive to motor cortical alpha and beta frequency oscillations. These oscillations are synchronised and amplified through the basal ganglia thalamocortical loop and entrained into the cerebello-thalamocortical loop via the cZI. On receiving potent gamma-aminobutyric acid (GABA)-ergic alpha and beta frequency oscillations in cZI afferents, ventrolateral (VL) thalamocortical neurons become hyperpolarised and rebound burst fire, generating 4-6 Hz tremor oscillations. We test this hypothesis by stimulating the cZI at alpha and beta frequencies using deep brain stimulation (DBS) in non-tremulous parkinsonian patients to see whether a 4-6 Hz tremor can be induced.

METHOD

This study included 11 patients with non-tremulous Parkinson's disease (PD), who had DBS leads implanted in a range of targets, including the cZI, STN, VL nucleus, globus pallidus internus (GPi), centromedian and parafascicular nucleus (CM/Pf), and the pedunculopontine nucleus (PPN). All patients underwent stimulation of active contacts within their respective targets at a standard pulse width, with frequencies ranging from 5 to 80 Hz up to a maximum tolerated voltage. The frequency of the tremor induced in the hands was recorded by accelerometry.

RESULT

Resting tremor in the 4-6 Hz range could be readily induced following stimulation of the cZI and the VL nucleus between 5 and 40 Hz. Tremor was also seen following STN stimulation; however, this was only at high stimulation voltages (>5 volts). No tremor could be induced following CM/Pf, PPN or GPi stimulation.

CONCLUSION

We discuss the implications of these findings and argue that resting tremor in PD is generated in the cortico-ZI-VL-thalamocortical loop rather than in the cortico-basal-ganglia-thalamocortical loop.

Bilateral stimulation of the caudal zona incerta nucleus for tremor control

INTRODUCTION

The ventrolateral (VL) nucleus of the thalamus is the commonly chosen target for deep brain stimulation (DBS) to alleviate tremor. However, it has a poor efficacy in alleviating proximal tremor and patients may develop tolerance to the action component of tremor. We performed bilateral stimulation of the caudal or motor part of the zona incerta nucleus (cZI) to determine its safety and efficacy in alleviating tremor.

METHODS

5 patients with parkinsonian tremor and 13 with a range of tremors (Holmes (HT), cerebellar (CT), essential (ET), multiple sclerosis (MS) and dystonic tremor (DT)) affecting both the proximal and distal body parts underwent MRI guided, bilateral cZI DBS. Tremor was assessed by the Fahn-Tolosa-Marin (FTM) tremor scale at baseline and at a mean follow-up of 12 months.

RESULTS

Resting PD tremor improved by 94.8% and postural tremor by 88.2%. The total tremor score improved by 75.9% in 6 patients with ET. HT improved by 70.2%, proximal CT by 60.4% and proximal MS tremor by 57.2% in the total tremor rating score. In the single patient with DT, there was improvement in both the dystonia and the tremor. Patients required low voltages of high-frequency stimulation and did not develop tolerance to it. Stimulation-related side effects were transient.

CONCLUSION

This prospective study shows that the cZI may be an alternative target for the treatment of tremor with DBS. In contrast to bilateral DBS of the VL nucleus, it improves all components of tremor affecting both the distal and proximal limbs as well as the axial musculature.

GDNF delivery for Parkinson's disease

The mainstays of Parkinson's disease (PD) treatment remain symptomatic, including initial dopamine replacement and subsequent deep brain stimulation, however, neither of these approaches is neuroprotective. Neurotrophic factors - proteins that activate cell signalling pathways regulating neuronal survival, differentiation, growth and regeneration - represent an alternative for treating dopaminergic neurons in PD but are difficult to administer clinically because they do not pass through the blood-brain barrier. Glial cell line-derived neurotrophic factor (GDNF) has potent neurotrophic effects particularly but not exclusively on dopaminergic neurons; in animal models of PD, it has consistently demonstrated both neuroprotective and neuroregenerative effects when provided continuously, either by means of a viral vector or through continuous infusion either into the cerebral ventricles (ICV) or directly into the denervated putamen. This led to a human PD study in which GDNF was administered by monthly bolus intracerebroventricular injections, however, no clinical benefit resulted, probably because of the limited penetration to the target brain areas, and instead significant side effects occurred. In an open-label study of continuous intraputamenal GDNF infusion in five patients (one unilaterally and four bilaterally), we reported excellent tolerance, few side effects and clinical benefit evident within three months of the commencement of treatment. The clinical improvement was sustained and progressive, and by 24-months patients demonstrated a 57 and 63% improvement in their off-medication motor and activities of daily living UPDRS subscores, respectively, with clear benefit in dyskinesias. The benefit was associated with a significant increase in putamenal 18F-dopa uptake on positron emission tomography (PET), and in one patient coming to autopsy after 43 months of unilateral infusion there was evident increased tyrosine hydroxylase immunopositive nerve fibres in the infused putamen. A second open trial in 10 patients using unilateral intraputamenal GDNF infusions has also demonstrated a greater than 30% bilateral benefit in both on- and off-medication scores at 24 weeks. Based on our 6-month results, a randomized controlled clinical trial was conducted to confirm the open-label results, however, GDNF infusion over 6-months did not confer the predetermined level of clinical benefit to patients with PD despite increased 18F-dopa uptake surrounding the catheter tip. It is possible that technical differences between this trial and the positive open label studies contributed to this negative outcome.

Cytomorphologic findings of hemangiopericytoma of the meninges: a case report

Hemangiopericytomas (HPCs) are tumors, constituting 2.5%, of soft tissue neoplasms. Meningeal hemangiopericytomas are rare non meningothelial mesenchymal tumors of the dura. They were classified as angioblastic meningiomas because of their similarity to meningiomas. However, these tumors are now regarded as distinct entities, akin to hemangiopericytoma elsewhere in the body. Few reports have addressed the fine needle aspiration (FNA) cytology of HPC. We present the cytological findings of one such rare case ofprimary meningeal hemangiopericytoma which metastasized to the lymph node. A 47 years male presented with cervical lymphadenopathy of 2 months duration. He was operated twice in the last 4 years and diagnosed atypical meningioma both times. The patient now also had spinal metastasis producing nerve root compression. Aspiration cytology of the node revealed cellular aspirate demonstrating round to oval cells with ample cytoplasm, round nuclei and inconspicuous nuclei. They showed a characteristic ferning out of blood vessels. Occasional mitosis was present. A diagnosis of malignant tumor of vascular origin was offered. Lymph node biopsy showed a characteristic histological picture of hemangiopericytoma described in other soft tissues. The cytology of this tumor is characteristic, but the rarity of the lesion, especially in metastatic sites makes diagnosis difficult unless a high index of suspicion is present. The recognition of the distinct cytological findings makes this possible. The case documents the role of FNA cytology in confirming HPC.

Effects of antihypertensive drug treatments on fracture outcomes: a meta-analysis of observational studies

OBJECTIVE

To quantitatively pool findings from observational studies on the risk of fracture outcomes associated with exposure to five antihypertensive drug classes: angiotensin-converting enzyme (ACE) inhibitors, diuretics (in particular thiazide diuretics), beta-blockers, calcium-channel blockers and alpha-blockers.

DESIGN

Systematic review and meta-analysis.

DATA SOURCES

Publications listed in the MEDLINE, EMBASE and LILACS databases, the ISI proceedings, and bibliographies of retrieved articles. Sources were searched from the earliest possible dates through December 2005.

REVIEW METHODS

We included case-control and cohort studies presenting relative risks and confidence intervals (CIs) for the association between exposure to antihypertensive agents and fracture outcomes. Data were extracted onto a standardized computer worksheet. Study quality was assessed using a 10-point questionnaire specific to case-control or cohort study design.

RESULTS

Fifty-four studies were identified. Pooled estimates were computed using the software HEpiMA. The pooled relative risk (RR) of any fracture with use of thiazide diuretics was 0.86 (95% CI 0.81-0.92) and 1.14 (95% CI 0.84-1.54) with use of nonthiazide diuretics. There was a statistically significant reduction of any fracture with use of beta-blockers, (RR 0.86, 95% CI 0.70-0.98). The one study with ACE inhibitor data showed protection (RR 0.81, 95% CI 0.73-0.89). No significant associations were found between fractures and exposure to alpha-blockers or calcium-channel blockers.

CONCLUSIONS

Thiazide diuretics and beta-blockers appear to lower the risk of fractures in older adults. However, these agents cannot be recommended as preventive therapies for fractures until data from randomized controlled trials have established their efficacy. Patients who use these inexpensive drugs as treatments for hypertension may also benefit from a reduction in fracture risk.

Oligomerization triggers binding of a Bacillus thuringiensis Cry1Ab pore-forming toxin to aminopeptidase N receptor leading to insertion into membrane microdomains

Bacillus thuringiensis Cry1A toxins, in contrast to other pore-forming toxins, bind two putative receptor molecules, aminopeptidase N (APN) and cadherin-like proteins. Here we show that Cry1Ab toxin binding to these two receptors depends on the toxins' oligomeric structure. Toxin monomeric structure binds to Bt-R1, a cadherin-like protein, that induces proteolytic processing and oligomerization of the toxin (Gomez, I., Sanchez, J., Miranda, R., Bravo A., Soberon, M., FEBS Lett. (2002) 513, 242-246), while the oligomeric structure binds APN, which drives the toxin into the detergent-resistant membrane (DRM) microdomains causing pore formation. Cleavage of APN by phospholipase C prevented the location of Cry1Ab oligomer and Bt-R1 in the DRM microdomains and also attenuates toxin insertion into membranes despite the presence of Bt-R1. Immunoprecipitation experiments demonstrated that initial Cry1Ab toxin binding to Bt-R1 is followed by binding to APN. Also, immunoprecipitation of Cry1Ab toxin-binding proteins using pure oligomeric or monomeric structures showed that APN was more efficiently detected in samples immunoprecipitated with the oligomeric structure, while Bt-R1 was preferentially detected in samples immunoprecipitated with the monomeric Cry1Ab. These data agrees with the 200-fold higher apparent affinity of the oligomer than that of the monomer to an APN enriched protein extract. Our data suggest that the two receptors interact sequentially with different structural species of the toxin leading to its efficient membrane insertion.

MRI directed bilateral stimulation of the subthalamic nucleus in patients with Parkinson's disease

OBJECTIVE

Bilateral chronic high frequency deep brain stimulation (DBS) of the subthalamic nucleus (STN) has emerged as an appropriate therapy for patients with advanced Parkinson's disease refractory to medical therapy. Advances in neuroimaging and neurophysiology have led to the development of varied targeting methods for the delivery of this treatment. Intraoperative neurophysiological and clinical monitoring is regarded by many to be mandatory for accurate STN localisation. We have examined efficacy of bilateral STN stimulation using a predominantly magnetic resonance imaging (MRI)-directed technique.

METHODS

DBS leads were stereotactically implanted into the STN using an MRI directed method, with intraoperative macrostimulation used purely for adjustment. The effects of DBS were evaluated in 16 patients followed up to 12 months, and compared with baseline assessments. Assessments were performed in both off and on medication states, and were based on the Unified Parkinson's Disease Rating Scale (UPDRS) and timed motor tests. Functional status outcomes were examined using the PDQ-39 quality of life questionnaire. A battery of psychometric tests was used to assess cognition.

RESULTS

After 12 months, stimulation in the off medication state resulted in significant improvements in Activities of Daily Living and Motor scores (UPDRS parts II and III) by 62% and 61% respectively. Timed motor tests were significantly improved in the off medication state. Motor scores (UPDRS part III) were significantly improved by 40% in the on medication state. Dyskinesias and off duration were significantly reduced and the mean dose of L-dopa equivalents was reduced by half. Psychometric test scores were mostly unchanged or improved. Adverse events were few.

CONCLUSIONS

An MRI directed targeting method for implantation of DBS leads into the STN can be used safely and effectively, and results are comparable with studies using intraoperative microelectrode neurophysiological targeting. In addition, our method was associated with an efficient use of operating time, and without the necessary costs of microelectrode recording.

Expression of an Aedes aegypti cation-chloride cotransporter and its Drosophila homologues

Insects maintain haemolymph homeostasis under different environmental conditions by modulating the concentrations of Na+, K+ and Cl- ions. One group of proteins involved in ion transport across cell membranes consists of cation-chloride cotransporters that form a family of structurally similar proteins. Although much is known about these proteins in mammalian systems, our understanding of them in insects is lacking. The recent sequencing of two insect genomes, Drosophila and Anopheles, enabled us to identify globally members of the family of cation chloride cotransporters in these insects. Using RT-PCR we monitored the transcription of members of this family in development and in several tissues. Our analyses showed that transcription of these genes differ considerably from the ubiquitously and highly expressed CG5594 gene to the almost silent gene CG31547. Comparison of Drosophila CG12773 and its Aedes homologue AaeCG12773 showed that they have similar transcript expression profiles. Immunohistochemical analysis of AaeCG1277 gene expression revealed that it is highly expressed in the gut of larvae and female adults but not in Malpighian tubules. A more detailed analysis showed that this protein is localized predominantly in the basolateral membrane of these tissues. This expression pattern confirmed the results of RT-PCR analysis. We also created a mutant for one of the genes, CG10413, in Drosophila using P-element excision. Analysis of this mutant showed this protein does not appear to be essential for development.

Chronic subdural haematoma and the enigmatic eosinophil

The membranes from 50 cases of chronic subdural haematomas were examined histologically and correlated with the duration of the lesion. Cases were divided into three groups based on duration from time of trauma and/or onset of clinical symptoms to date of surgery - Group I: 1 to 30 days, Group II: 31 to 90 days and Group III: >90 days. Infiltration with eosinophils was observed in the vascularised and hyalinised granulation tissue of the subdural membrane in 30 of the 50 cases (60%). There was a trend to correlation both of the frequency and the extent of eosinophilic infiltration with duration of haematoma. Thus, eosinophils were encountered in about half the cases with duration up to 3 months which increased to 80% in cases with duration more than 3 months. The extent of eosinophilic infiltration (mild, moderate or severe) also appeared to correlate with duration of haematoma in that mild infiltration was more common in Group I cases while moderate to severe infiltration were more frequently observed in Group II and III cases. No correlation was observed of the eosinophilic infiltrate with age and sex of the patients or with presence of other cellular inflammatory components of the membrane. Interestingly, a finding hitherto unreported in English literature was the demonstration of mast cells in 7 of 16 membranes (44%) which had been stained using toluidine blue. It is possible that the eosinophils appear at this unusual site due to chemotactic stimulus abetted by these mast cells as well as lymphocytes and haemosiderin pigment. The eosinophils may have an important role in the repair and healing process of these membranes.

Laminal fenestration for the treatment of lumbar nerve root foraminal stenosis

A new technique is reported for the treatment of isolated lumbar nerve root foraminal stenosis. Nerve root decompression is performed via a 5-mm drill hole in the lamina immediately below the superior facet. This technique preserves spinal stability even if done at multiple levels. It also provides early mobility of the patient and subsequently shortens the hospital stay. The technical details are described.

The influence of preoperative nutritional status in wound healing after replacement arthroplasty

Patient nutritional status was evaluated preoperatively using the serological parameters serum albumin, serum transferrin, and total lymphocyte count in 40 patients who underwent replacement arthroplasty (33 hips and 7 knees). Using the standard criteria, the overall incidence of malnutrition was 40% (16 cases). Ten percent (4 patients) had a negative value in the Rainey McDonald nutritional index. On follow-up, no patient had delayed wound healing or wound infection. Attention to surgeon-dependent factors can offset the high risk of delayed wound healing imposed by patient-dependent factors.

Comparative strength of three methods of fixation of transverse acetabular fractures

With the advent of percutaneously placed lag screws for fixation of acetabular fractures, this study evaluated the strength of lag screw fixation compared with traditional fixation techniques of transverse acetabular fractures. Ten formalin-treated human, cadaveric pelvic specimens with bilateral, transtectal transverse acetabular fractures were used for this study. The right acetabular fractures were fixed with a five-hole plate and four screws with the central hole spanning the posterior fracture site. The left acetabular fractures were fixed with two lag screws, one each in the anterior and posterior columns, or with a screw and wire construct stabilizing both columns. The specimens were loaded to implant failure. Stiffness, yield strength, maximum load at failure, and site of failure was recorded. The plate and screw construct showed significantly greater yield and maximum strength when compared with the two lag screws. The stiffness of the lag screw method was 39% higher than that of the plating method, but this result was not statistically significant. In addition, the plate and screw method provided significantly greater maximum strength than the screw and wire technique. The quadrilateral plate seemed to be the weakest area of fixation because 83% of the implant failures occurred in this region. In patients in whom the risks of formal open reduction and internal fixation of acetabular fractures outweigh the possible benefits, such as in patients with burns or degloved skin, the advent of computer-assisted and fluoroscopically guided percutaneous surgical techniques have been instrumental. This study showed there is greater strength of fixation with a plate and screw construct, possibly secondary to supplementary fixation distal to the quadrilateral plate. However, lag screw fixation provided relatively greater stiffness, which may account for its clinical success. Percutaneous lag screw fixation of appropriate transverse acetabular fractures is a viable option.

Small intestinal neoplasms

Small intestinal neoplasms are uncommonly encountered in clinical practice. They may occur sporadically, in association with genetic diseases (e.g., familial adenomatous polyposis coli or Peutz-Jeghers syndrome), or in association with chronic intestinal inflammatory disorders (e.g., Crohn's disease or celiac sprue). Benign small intestinal tumors (e.g., leiomyoma, lipoma, hamartoma, or desmoid tumor) usually are asymptomatic but may present with intussusception. Primary malignancies of the small intestine-including adenocarcinoma, leiomyosarcoma, carcinoid, and lymphoma-may present with intestinal obstruction, jaundice, bleeding, or pain. Extraintestinal neoplasms may involve the intestine via contiguous spread or peritoneal metastasis. Hematogenous metastases to the intestine from an extraintestinal primary are unusual and are most typical of melanoma. Because the small intestine is relatively inaccessible to routine endoscopy, diagnosis of small intestinal neoplasms is often delayed for months after onset of symptoms. When the diagnosis is suspected, enteroclysis is the most useful imaging study. Small bowel endoscopy (enteroscopy) is increasingly widely available and may permit earlier, nonoperative diagnosis.

Posterior-only unit rod instrumentation and fusion for neuromuscular scoliosis

STUDY DESIGN

A retrospective study to determine the efficacy of posterior-only unit rod instrumentation and fusion in a skeletally immature neuromuscular scoliosis population.

OBJECTIVE

To determine whether the posterior-only approach to this population adequately addresses the concerns of correction of scoliosis and pelvic obliquity, maintenance of that correction over time, and the incidence of crankshaft phenomenon.

SUMMARY OF BACKGROUND DATA

Controversy exists regarding the need for anterior release to improve curve flexibility and the need to obtain an anterior arthrodesis in those skeletally immature patients at risk for crankshafting with continued anterior growth.

METHODS

From 1992 through 1997, 28 consecutive skeletally immature patients with neuromuscular scoliosis underwent posterior-only unit rod instrumentation and fusion for the treatment of progressive, symptomatic spinal deformities. Preoperative, immediate postoperative, and final follow-up radiographs were analyzed with respect to scoliosis and pelvic obliquity correction, maintenance of that correction over time, and the development of the crankshaft phenomenon as evidenced by loss of correction and/or increased rib-vertebral angle difference. The average age of the patients was 12.8 years and the average follow-up was 58 months with a minimum of 2 years.

RESULTS

Twenty-six patients were available for final follow-up. The initial Cobb angle correction averaged 66%, with 75% of the pelvic obliquity corrected. These corrections were maintained over time. Before surgery 27 of 28 patients were Risser 0, 1, or 2. The triradiate cartilage was open in nine patients, and five patients were < or =10 years of age. At the final follow-up 22 of the 26 patients were Risser 5 and 4 were Risser 4. There was one patient with increased rib-vertebral angle difference over the length of follow-up, with no loss of frontal or sagittal plane alignment.

CONCLUSIONS

These results indicate that even in the very young neuromuscular patient, acceptable amounts of curve correction can be achieved and maintained with posterior-only unit rod instrumentation and fusion. The biomechanical stiffness of this construct seemed to be able to prevent the crankshaft phenomenon in the majority of those patients at risk.

Improving prescribing in the elderly: a study in the long term care setting

OBJECTIVES

To determine the prevalence and predictors of potentially inappropriate prescribing of medications in the long term care setting, and to determine the effectiveness of follow-up pharmacist letters to the prescribing physicians in improving prescribing.

PATIENTS AND METHODS

The Improving Prescribing in the Elderly Tool was applied to the charts of all long term care patients aged 65 years and over at Parkwood Hospital, a rehabilitation hospital/long term care facility in London, Ontario. All potentially inappropriate prescriptions were verified by a consensus panel consisting of a family physician, a geriatric medicine specialist and a geriatric pharmacist. Follow-up letters to the prescribing physicians were developed that briefly described the concerns with the potentially inappropriate prescriptions and suggested safer alternatives. These letters were sent to the prescribing physicians, accompanied by a brief survey. Patient charts in which a potentially inappropriate prescription had been noted were reviewed for prescription changes two months after the prescribing physicians had received the follow-up letters.

RESULTS

A total of 69 potentially inappropriate prescriptions were found in 65 of 355 long term care patients (18.3%). The most common types of potentially inappropriate prescriptions were anticholinergic drugs to manage antipsychotic side effects (17 cases), tricyclic antidepressants with active metabolites (16 cases), and long-acting benzodiazepines (14 cases). The total number of prescription medications (P<0.001), a history of mental illness (P=0.002) and a high minimum data set (MDS) score for depression (P=0.002) were all highly associated with potentially inappropriate prescribing. Variables that were not correlated with increased rates of potentially inappropriate prescribing included age, sex, code status, a diagnosis of dementia (as documented explicitly in the chart), high MDS scores for delirium or cognitive impairment, the date of the prescribing physician's graduation and the total Charlson comorbidity index score. Potentially inappropriate prescriptions were significantly less common in patients seen by a geriatric medicine specialist (P<0.001). In response to the follow-up letter suggesting safer alternatives, 37.9% of potentially inappropriate prescriptions were changed by the prescribing physician. Ninety-two per cent of responding physicians rated the follow-up letter as a "somewhat" or "very" helpful method for improving prescribing in elderly patients.

CONCLUSIONS

Potentially inappropriate prescribing in the long term care setting is common and can be improved by the provision of a follow-up letter suggesting safer alternatives.

Mapping the epitope in cadherin-like receptors involved in Bacillus thuringiensis Cry1A toxin interaction using phage display

In susceptible lepidopteran insects, aminopeptidase N and cadherin-like proteins are the putative receptors for Bacillus thuringiensis (Bt) toxins. Using phage display, we identified a key epitope that is involved in toxin-receptor interaction. Three different scFv molecules that bind Cry1Ab toxin were obtained, and these scFv proteins have different amino acid sequences in the complementary determinant region 3 (CDR3). Binding analysis of these scFv molecules to different members of the Cry1A toxin family and to Escherichia coli clones expressing different Cry1A toxin domains showed that the three selected scFv molecules recognized only domain II. Heterologous binding competition of Cry1Ab toxin to midgut membrane vesicles from susceptible Manduca sexta larvae using the selected scFv molecules showed that scFv73 competed with Cry1Ab binding to the receptor. The calculated binding affinities (K(d)) of scFv73 to Cry1Aa, Cry1Ab, and Cry1Ac toxins are in the range of 20-51 nm. Sequence analysis showed this scFv73 molecule has a CDR3 significantly homologous to a region present in the cadherin-like protein from M. sexta (Bt-R(1)), Bombyx mori (Bt-R(175)), and Lymantria dispar. We demonstrated that peptides of 8 amino acids corresponding to the CDR3 from scFv73 or to the corresponding regions of Bt-R(1) or Bt-R(175) are also able to compete with the binding of Cry1Ab and Cry1Aa toxins to the Bt-R(1) or Bt-R(175) receptors. Finally, we showed that synthetic peptides homologous to Bt-R(1) and scFv73 CDR3 and the scFv73 antibody decreased the in vivo toxicity of Cry1Ab to M. sexta larvae. These results show that we have identified the amino acid region of Bt-R(1) and Bt-R(175) involved in Cry1A toxin interaction.

Drosophila RNase H1 is essential for development but not for proliferation

Ribonucleases H (RNases H) recognize and specifically degrade RNA that is bound to complementary DNA and are thought to be involved in DNA replication and transcriptional regulation. Though it was previously shown that bacterial RNases H participate in DNA synthesis, none of the known mutations in RNase H genes in either prokaryotes or lower eukaryotes is lethal. Here, we report the characterization of the first loss-of-function mutation in an RNase H1 gene in a metazoan organism, Drosophila melanogaster. Genetic studies of this mutant showed that this gene is essential for metamorphosis in Drosophila. However, disruption of the RNase H1 gene does not affect proliferation, but probably alters the regulation of gene expression. The lethal phenotype of this mutant also demonstrates that RNase H1 activity in Drosophila cannot be provided by other cellular RNase H activities. Analysis of the developmental and spatial expression profiles of a reporter gene placed under the control of the RNase H1 promoter revealed increased expression in several larval tissues. In salivary glands this increase was shown to be inducible by treatment with ecdysone.

Fractures in transfusion dependent beta thalassemia--an Indian study

AIM OF STUDY

To analyse the incidence of fractures in beta thalassemia patients and to identify causative factors.

METHODS

We examined all cases of transfusion dependent beta thalassemia (TDBT) seen at our institute over a two-year period. The transfusion records, incidence of fractures, cause of fracture and Hb levels were recorded. Radiographs of the involved parts were taken in cases with fractures only.

RESULTS AND CONCLUSIONS

Amongst 105 cases of TDBT assessed, 14 sustained a total of 28 fractures. Seven patients sustained more than one fracture. Two thirds of these fractures were caused by trivial trauma. All fractures, except one, were of the closed type. Radiologically, fractures frequently showed minimal or no displacement. All fractures were successfully treated by closed modalities of treatment. Majority of the fractures healed within normal union time for a given bone. Permanent deformities and gross limb length discrepancies were uncommon. On reviewing the literature, we noted that the incidence of fractures in our series and in the latest reports was lesser than previously reported. We postulate that this is a result of better and earlier control of hemoglobin status by improved transfusion techniques, and earlier recognition of the disease. Difficulties arise due to inadequate blood transfusion facilities in developing countries.

Glutamate receptors in peripheral tissues: current knowledge, future research, and implications for toxicology

We illustrate the specific cellular distribution of different subtypes of glutamate receptors (GluRs) in peripheral neural and non-neural tissues. Some of the noteworthy locations are the heart, kidney, lungs, ovary, testis and endocrine cells. In these tissues the GluRs may be important in mediating cardiorespiratory, endocrine and reproductive functions which include hormone regulation, heart rhythm, blood pressure, circulation and reproduction. Since excitotoxicity of excitatory amino acids (EAAs) in the CNS is intimately associated with the GluRs, the toxic effects may be more generalized than initially assumed. Currently there is not enough evidence to suggest the reassessment of the regulated safety levels for these products in food since little is known on how these receptors work in each of these organs. More research is required to assess the extent that these receptors participate in normal functions and/or in the development of diseases and how they mediate the toxic effects of EAAs. Non-neural GluRs may be involved in normal cellular functions such as excitability and cell to cell communication. This is supported by the wide distribution in plants and animals from invertebrates to primates. The important tasks for the future will be to clarify the multiple biological roles of the GluRs in neural and non-neural tissues and identify the conditions under in which these are up- or down-regulated. Then this could provide new therapeutic strategies to target GluRs outside the CNS.

The transporter-like protein inebriated mediates hyperosmotic stimuli through intracellular signaling

We cloned the inebriated homologue MasIne from Manduca sexta and expressed it in Xenopus laevis oocytes. MasIne is homologous to neurotransmitter transporters but no transport was observed with a number of putative substrates. Oocytes expressing MasIne respond to hyperosmotic stimulation by releasing intracellular Ca(2+), as revealed by activation of the endogenous Ca(2+)-activated Cl(−) current. This Ca(2+) release requires the N-terminal 108 amino acid residues of MasIne and occurs via the inositol trisphosphate pathway. Fusion of the N terminus to the rat gamma-aminobutyric acid transporter (rGAT1) also renders rGAT1 responsive to hyperosmotic stimulation. Immunohistochemical analyses show that MasIne and Drosophila Ine have similar tissue distribution patterns, suggesting functional identity. Inebriated is expressed in tissues and cells actively involved in K(+) transport, which suggests that it may have a role in ion transport, particularly of K(+). We propose that stimulation of MasIne releases intracellular Ca(2+) in native tissues, activating Ca(2+)-dependent K(+) channels, and leading to K(+) transport.

Tuberculous anal sepsis: report of clinical features in 20 cases

INTRODUCTION

Tuberculosis is a neglected cause of anal sepsis, often is not recognized, and therefore is not treated properly.

METHOD

All patients were reviewed who had tuberculous anal sepsis diagnosed by histology reports of fistulectomy specimens or abscess scrapings from January 1990 to April 1999.

RESULTS

Twenty patients (median age, 53 years; 18 males) with anal tuberculous sepsis were identified. They presented with abscesses (n = 2), abscesses and fistulas (n = 6), or fistulas (n = 12). All patients had a long history of anal complaints (3 months to 20 years), for which 15 patients were operated on previously. Nearly all fistulas (17/18) were complex, and secondary tracks or additional complicating features were common, even at first presentation. Eight patients had active concurrent pulmonary tuberculosis, and six showed evidence of previous pulmonary tuberculosis. Six patients had no signs of concurrent or previous tuberculosis elsewhere. Recurrence was observed only in cases where tuberculosis was initially not recognized, and antitubercular treatment therefore was not started.

CONCLUSION

Contrary to views held previously, anal tubercular sepsis seems to have characteristic clinical features. It should be considered in cases of known pulmonary or extrapulmonary tuberculosis or if anal sepsis is persistent, recurrent, or complex in nature.

New approach to cervical flexion deformity in ankylosing spondylitis. Case report

The treatment of cervical fixed flexion deformity in ankylosing spondylitis presents a challenging problem that is traditionally managed by a corrective cervicothoracic osteotomy. The authors report a new approach to this problem that involves performing a two-level osteotomy at the level of maximum spinal curvature, thereby achieving complete anatomical correction in a one-stage procedure. This 48-year-old woman with ankylosing spondylitis presented with a 30-year history of progressive neck deformity that left her unable to see ahead and caused her to experience difficulty eating, drinking, and breathing on exertion. On examination, she exhibited a 90 degrees fixed flexion deformity of the cervical spine, which was maximum at C-4; this was confirmed on imaging studies. A two-level osteotomy was performed at C3-4 and C4-5 around the area of maximum spinal curvature, and the deformity was corrected by extending the head on its axis of rotation through the uncovertebral joints. The spine was stabilized using a Ransford loop. An excellent anatomical position was achieved, as was complete correction of the deformity. A two-level midcervical osteotomy performed at the level of maximum spinal curvature in ankylosing spondylitis enables complete correction of severe fixed flexion deformity in a single procedure. Preservation of the uncovertebral joints allows smooth and safe correction of the deformity about their axis of rotation.

Temporal and spatial expression of the cell-cycle regulator cul-1 in Drosophila and its stimulation by radiation-induced apoptosis

Cul-1 protein is part of the ubiquitin ligase complex that is conserved from yeast to humans. This complex specifically marks cell-cycle regulators for their subsequent destruction. Two null mutations of the cul-1 gene are known, in budding yeast and in nematodes. Although in both these organisms the cul-1 gene executes essentially the same function, the manifestation of its lack-of-function mutations differs considerably. In yeast the mutation causes arrest at the G(1)/S-phase transition, whereas in nematodes excessive cell divisions occur because mutant cells are unable to exit the mitotic cycle. We isolated cul-1 orthologues from two model organisms, Drosophila melanogaster and mouse. We show that the Drosophila full-length cul-1 gene restores the yeast mutant's inability to pass through the G(1)/S-phase transition. We also characterize expression of this gene at the transcript and protein levels during Drosophila development and show that cul-1 gene is maternally supplied as a protein, but not as an RNA transcript. Zygotic transcription of the gene, however, resumes at early stages of embryogenesis. We also found an increase in cul-1 transcription in cultured cells treated with a lethal dose of gamma-irradiation.

Tuberculous osteomyelitis of the cuboid: a report of four cases

Osteoarticular tuberculosis, although rare, has shown a resurgence in recent times, especially in immunocompromised patients. Involvement of the foot is infrequent, and the differential diagnosis is confusing, leading to diagnostic delays. We reviewed four cases of tuberculosis of the cuboid where the infection was limited to the bone without articular involvement. All four cases were adults and diagnostic delays were observed in all. Three of the cases had an osteolytic lesion on radiographs resembling a space-occupying lesion. Magnetic resonance imaging (MRI) or Computed tomography (CT) scans were helpful in three cases, and post-treatment MRI helped in evaluating outcome in one case. Antitubercular chemotherapy was sufficient to cause resolution of the lesion in three cases, while in one case surgical intervention was necessary. Since isolated osteomyelitis is usually seen only in the early stages of the disease process, early diagnosis and appropriate therapy are imperative to get good long-term results. Concomitant extraskeletal lesions are not always seen, nor is the organism cultured in a majority of the cases. Thus a high index of suspicion is mandatory in high-risk groups (immigrants, immunocompromised cases or those with history of contact); clinical and radiologic features, along with histopathologic evidence of granulomatous pathology should be sufficient to initiate therapy.