Intra-hippocampal tonic inhibition influences formalin pain-induced pyramidal cell suppression, but not excitation in dorsal field CA1 of rat

It has been hypothesized that intra-hippocampal GABAergic inhibitory interneurons mediate formalin pain-induced suppression of dorsal hippocampal CA1 pyramidal cell discharge. The present study performed on anaesthetized rats tested the hypothesis by disrupting GABAergic mechanisms with intra-hippocampal administration of the GABA(A) receptor antagonist bicuculline methiodide, applied either dorsally into the pyramidal cell layer and stratum oriens (dorsal-bicuculline) or ventrally into the region of apical dendrites (ventral-bicuculline). It was found that ventral-, but not dorsal-bicuculline attenuated formalin-induced suppression of pyramidal cell extracellular discharge. The antagonism was selective in such a way that the excitation of pyramidal cell was unaffected. Interestingly, ventral-bicuculline strongly disinhibited CA1 pyramidal cells and shifted the distribution of their spontaneous discharge to values higher than the control group. However, dorsal-bicuculline disinhibited the local CA1 interneurons that were strongly excited on injection of formalin. Overall, the findings favour the notion that tonic GABA(A) receptor mechanisms located in the region of apical dendrites facilitate formalin-induced pyramidal cell suppression by masking the background excitatory drive impinging on the pyramidal cells. Interestingly, both the attenuation of formalin-induced inhibition and facilitation of basal discharge of CA1 pyramidal cells by ventral-bicuculline are similar to the effects seen previously with the destruction of medial septal cholinergic neurons. This convergence of effects strengthens the proposal that the network of medial septal cholinergic neurons and hippocampal GABAergic interneurons influence formalin pain-induced CA1 pyramidal cell suppression. In addition, the data point to a non-overlapping excitatory drive whose strength is unaffected by the inhibitory drive that underpins formalin suppression.

A nociceptive-intensity-dependent role for hydrogen sulphide in the formalin model of persistent inflammatory pain

The present study investigated the hypothesis that hydrogen sulfide (H2S) is pro-nociceptive in the formalin model of persistent inflammatory pain in the adult rat. Hind paw injection of formalin evoked a concentration-dependent increase in the hind paw concentration of H2S. Increased concentration of H2S was found in homogenates prepared from hind paws injected with 5% (but not 1.25%) formalin. Correspondingly, animal nociceptive flinching and hind paw edema were maximal with 5% formalin. Both nociceptive flinching and hind paw edema induced by injection of 5% formalin were attenuated by pretreatment with DL-propargylglycine (PPG; 50 mg/kg, i.p.) which is an inhibitor of the H2S synthesizing enzyme cystathionine-gamma-lyase (CSE). The effect of pretreatment with PPG was selective and the drug did not influence animal behavior or hind-paw edema with injection of 1.25% formalin. Furthermore, PPG pretreatment attenuated the induction of c-Fos in spinal laminae I-II following injection of 5% formalin. In contrast, co-injection of 1.25% formalin with sodium hydrogen sulfide (NaHS; 1 nmol/0.1 ml), a H2S donor, into the hind paw increased animal nociceptive behavior. Collectively, these findings show that the effect of peripheral H2S in the pathogenesis of inflammatory pain depends, at least in part, on the nociceptive intensity level.

Auditing bone densitometry and fractures in children with chronic disease

In a retrospective analysis of bone densitometry scans performed in an audit of 576 children with chronic disease, lean-mass-adjusted bone mineral content (BMC) for the total body and the lumbar spine was marginally lower in children with fractures. However, the predictive ability of different bone mineral densities (BM) and BMC cut-offs to identify fracture risk in children with chronic disease needs to be tested for specific disease conditions in larger prospective studies.

Psychiatric manifestations in Wilson's disease: a cross-sectional analysis

Behavioral and psychiatric abnormalities in Wilson's disease (WD) have a variable frequency and spectrum. This study involved evaluation of the psychiatric comorbidities in patients of Wilson's disease, using structured clinical interview for DSM-IV Axis-I disorders (SCID). Among the 50 confirmed patients with Wilson's disease recruited for this study, 12 patients (24%) fulfilled the diagnostic criteria for syndromic psychiatric diagnosis: bipolar affective disorder (18%), major depression (4%), and dysthymia (2%). Formal assessment of psychopathology in all patients with Wilson's disease may have therapeutic significance.

Oxidative stress in hypertension: association with antihypertensive treatment

There is growing evidence that oxidative stress contributes to the pathogenesis of hypertension. Our aim was to measure oxidative stress in hypertensive subjects, and assess the potential confounding influences of antihypertensive therapy. Serum malondialdehyde and antioxidant levels were estimated in patients at the time of presentation and also after a antihypertensive therapy for 3 months. During the period of study no antioxidant/s was given to the patients and control subjects. Mean blood pressure values were altered in the hypertensive patients following antihypertensive therapy from their respective values observed at the time of presentation. Serum malondialdehyde levels were significantly higher in the hypertensive patients in comparison to control cases. The antioxidant activity of enzymes super oxide dismutase, glutathione and non enzymatic antioxidant levels of vitamins E and C were significantly lower in patients compared to controls. After 3 months of antihypertensive treatment all the above parameters showed reversal in the respective levels of serum malondialdehyde and antioxidant activity. Antihypertensive medications lower the blood pressure and thereby results in reduced oxidative stress which indicates that oxidative stress is not the cause, but rather a consequence, of hypertension.

Conversion from standard opioid therapy to once-daily oral extended-release hydromorphone in patients with chronic cancer pain

This open-label, multicenter study assessed the efficacy and tolerability of conversion to once-daily OROS hydromorphone from previous opioid agonist therapy in patients with chronic cancer pain. Patients were stabilized on their previous therapy before conversion at a 5:1 ratio of morphine sulfate to hydromorphone hydrochloride. The OROS hydromorphone dose was titrated over 3 - 21 days to achieve effective analgesia and was maintained for up to 14 days. Efficacy was assessed using the Brief Pain Inventory (BPI). Adverse events and vital signs were monitored. Dose stabilization was achieved in 119 of the 127 (94%) patients who received the study medication; in 77%, stabilization was achieved with no titration steps. Mean BPI pain intensity ratings and BPI pain interference scores decreased significantly after OROS hydromorphone treatment compared with pretreatment values. Mean pain-relief level remained stable after conversion and throughout treatment with OROS hydromorphone. Adverse events were as expected for cancer patients receiving opioid agonists. There were no clinically significant changes in vital signs.

Dominant psychiatric manifestations in Wilson's disease: A diagnostic and therapeutic challenge!

INTRODUCTION

Recognition of psychiatric manifestations of Wilson's disease (WD) has diagnostic and therapeutic implications.

OBJECTIVE

To describe the clinical features and psychopathology of patients with WD who had initial or predominant psychiatric manifestations.

PATIENT AND METHODS

Records of 15 patients with WD (M:F: 11:4), from a large cohort of 350 patients, with predominant psychiatric manifestations at onset were reviewed. Their initial diagnosis, demographic profile, family history, pre-morbid personality, clinical manifestations, treatment and outcome were recorded.

RESULTS

Their mean age at diagnosis was 19.8+/-5.8 years. Six patients were born to consanguineous parentage and two patients each had family history of WD and past history of psychiatric illness. Diagnosis of WD was suspected by detection of KF rings (all), observing sensitivity to neuroleptics (n=2), history of jaundice (n=2) and family history suggestive of WD (n=9). Psychiatric manifestations could be classified as affective disorder spectrum (n=11) and schizophreniform-illness (n=3). While the psychiatric symptoms improved in five patients with de-coppering therapy, seven patients needed symptomatic treatment as well. Three of the four patients who responded to de-coppering therapy were sensitive to neuroleptics. Long-term follow up of 10 patients revealed variable recovery.

CONCLUSIONS

Young patient with psychiatric manifestations with clues like history of jaundice, family history of neuropsychiatric manifestations and sensitivity to neuroleptics should be evaluated for WD to avoid delay in diagnosis and associated morbidity.

SIGNIFICANT OUTCOMES

The study reemphasizes the importance of behavioral manifestations in Wilson disease in terms of diagnosis and management difficulties.

LIMITATIONS

Retrospective nature of the study.

Chronic ataxic neuropathy mimicking dorsal midbrain syndrome

We describe the clinical course, with special attention to the disturbance of eye movements, of a 29-year-old man with chronic ataxic neuropathy with ophthalmoplegia, IgM paraprotein, cold agglutinins and anti-GD1b disialosyl antibodies (CANOMAD). Using the magnetic search coil technique, we documented convergence during upward saccades and other features suggestive of dorsal midbrain syndrome. Thus, in common with Miller Fisher syndrome, CANOMAD may present with clinical findings implicating involvement of the central nervous system, which contains ganglioside antigens to anti-GD1b antibodies.

Once-daily OROS hydromorphone for the management of chronic nonmalignant pain: a dose-conversion and titration study

BACKGROUND

The use of opioid analgesics for patients with chronic nonmalignant pain is becoming more widely accepted, and long-acting formulations are an important treatment option.

AIM

To assess conversion to extended-release OROS hydromorphone from previous stable opioid agonist therapy in patients with chronic nonmalignant pain of moderate-to-severe intensity.

METHODS

In this open-label multicentre trial, patients were stabilised on their previous opioid therapy before being switched to OROS hydromorphone at a ratio of 5 : 1 (morphine sulphate equivalent to hydromorphone hydrochloride). The OROS hydromorphone dose was titrated over 3-16 days to achieve effective analgesia, and maintenance treatment continued for 14 days.

RESULTS

Study medication was received by 336 patients; 66% completed all study phases. Stabilisation of OROS hydromorphone was achieved by 94.6% of patients, the majority in two or fewer titration steps (mean time, 4.2 days). Mean pain intensity scores, as determined by the Brief Pain Inventory, decreased during OROS hydromorphone treatment (p <or= 0.001). The percentage of patients rating their pain relief as 'good' or 'complete' increased, and the use of rescue analgesics for breakthrough pain decreased. The interference of pain with everyday activities (e.g. walking or work), and the effects on mood and enjoyment of life, also improved during the study (all p < 0.001). OROS hydromorphone was well tolerated, and adverse events were those expected for opioid agonist therapy.

CONCLUSION

Patients with chronic nonmalignant pain who had been receiving opioid therapy easily underwent conversion to OROS hydromorphone, with no loss of efficacy or increase in adverse events.

Manual displacement of the uterus during Caesarean section

Ninety ASA 1 and 2 pregnant women with term singleton pregnancies and no maternal and fetal complications, scheduled for elective or emergency Caesarean section, were randomly allocated to group LT (15 degrees left lateral table tilt, n = 45) and group MD (leftward manual displacement, n = 45). Subarachnoid block was established with a 25-gauge spinal needle at the L3-L4 interspace using 1.5 ml of 0.5% hyperbaric bupivacaine. A median sensory level of T6 was observed in both groups but the incidence of hypotension was markedly lower in group MD when compared to group LT (4.4% vs 40%; p < 0.001) with a significant reduction in mean (SD) ephedrine requirement (6 (0) vs 11.3 (4.9) mg; p < 0.001). The mean (SD) fall in systolic blood pressure was 28.8 (7.3) mmHg in group LT and 20 (12.7) mmHg in group MD. The time to maximum fall in systolic blood pressure was similar in both groups (4.5 min). We conclude that manual displacement of the uterus effectively reduces the incidence of hypotension and ephedrine requirements when compared to 15 degrees left lateral table tilt in parturients undergoing Caesarean section.

Slow-release fluoride devices for the control of dental decay

BACKGROUND

Slow-release fluoride devices have been investigated as a potentially cost-effective method of reducing dental caries in those with high risk of disease.

OBJECTIVES

To evaluate the effectiveness of different types of slow-release fluoride devices on preventing, arresting, or reversing the progression of carious lesions on all surface types of deciduous and permanent teeth.

SEARCH STRATEGY

We searched (up until February 2005) multiple electronic databases (Cochrane Oral Health Group's Trials Register, CENTRAL, MEDLINE, EMBASE), bibliographic references of identified randomised controlled trials (RCTs), textbooks, review articles, and meta-analyses. Letters were sent to authors of identified RCTs asking for clarifications and unpublished or ongoing research. Relevant journals were handsearched for more recent reports than those obtained from databases.

SELECTION CRITERIA

Randomised or quasi-randomised controlled trials (RCTs) comparing slow-release fluoride devices with an alternative fluoride treatment, placebo, or no intervention in all age groups. The main outcomes measures sought were changes in numbers of decayed, missing, and filled teeth or surfaces (DMFT/DMFS in permanent teeth or dmft/dmfs in primary teeth) and progression of carious lesions through enamel and into dentine.

DATA COLLECTION AND ANALYSIS

Abstracts of all reports identified were considered independently by two review authors and full reports obtained of any potentially relevant articles to allow further assessment for relevance and validity. Data extraction and quality assessment were conducted independently by two and three review authors respectively, with arbitration by the fourth. Where uncertainty existed, authors were contacted for additional information.

MAIN RESULTS

Only one trial involving 174 children fully met the criteria for inclusion in this review. Although 132 children were still included in the trial at the 2-year completion point, examination and statistical analysis was performed on only the 63 children who had retained the beads. Thirty-one of these were in the intervention group and 32 in the control group. Amongst these 63 children, caries increment was reported to be statistically significantly lower in the intervention group than in the placebo group (mean difference: -0.72 DMFT, 95% confidence interval -1.23 to -0.21 and -1.52 DMFS, 95% confidence interval -2.68 to -0.36)

AUTHORS' CONCLUSIONS

There is some evidence of a caries-inhibiting effect of slow-release fluoride glass beads. This evidence is regarded as weak and unreliable because the results were from participants selected on the basis of bead retention rather than an intention-to-treat analysis.

Routine short course pre-op radiotherapy or selective post-op chemoradiotherapy for resectable rectal cancer? Preliminary results of the MRC CR07 randomised trial

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Background: Radiotherapy reduces local recurrence (LR) when combined with surgery in resectable rectal cancer. The Medical Research Council CR07 trial was designed to compare two different radiotherapy policies when combined with mesorectal excision. Methods: Patients with operable non-metastatic adenocarcinoma of the rectum were randomised to either routine pre-op short course radiotherapy [25Gy/5F] (PRE) or selective post-op chemoradiotherapy (POST) for patients with involvement of the circumferential resection margin (CRM) - [45Gy/25F + 5fluorouracil]. Results: A total of 1350 patients were randomised from 52 centres in the UK, Canada, New Zealand and South Africa between March 1998 and August 2005. Median follow-up is 3 years. Patients (73% male, median age 65 years, 79% PS0) were well balanced between the 2 arms. 595 of 674 (88%) of the pre-op group received their allocated treatment. Of the 676 patients allocated to the selective post-op chemoradiotherapy arm, 73 (11%) were CRM +ve and 51 of these (70%) received chemoradiotherapy. Post operative chemotherapy was received by 85% of patients with stage III disease. At the time of analysis 23 PRE and 61 POST patients had confirmed LR, 96 and 106 patients respectively distant metastases, and 115 and 146 respectively had died. The 3 year rates for LR (primary end point) were 4.7% and 11.1% for PRE and POST groups respectively (HR 2.47, 95% CI 1.61–3.79), for disease free survival 79.5% and 74.9% (HR 1.31, 95% CI 1.02–1.67) and for overall survival 80.8% and 78.7% (HR 1.25, 95% CI 0.98–1.59. The LR benefit in favour of PRE was consistent for tumours 0–5,5–10 and >10cm from the anal verge (HR 2.00, 2.14 and 4.97 respectively). Further subset analysis based on TNM stage and operation performed will be presented. Conclusions: These preliminary results indicate that routine short course pre-operative radiotherapy results in a signifcant reduction in local recurrence and improved disease free survival at 3 years when compared with a highly selective post operative approach.

No significant financial relationships to disclose.

Local recurrence after rectal cancer resection is strongly related to the plane of surgical dissection and is further reduced by pre-operative short course radiotherapy. Preliminary results of the Medical Research Council (MRC) CR07 trial

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Background: The MRC CR07 trial compared routine short course pre-operative radiotherapy (PRE) with selective post-operative chemo-radiation if there was involvement of the circumferential resection margin (CRM) (POST) and included a prospective pathological assessment of the quality of resection of the surgical specimen. Methods: A total of 1350 patients were randomised from 52 centres between March 1998 and August 2005. Median follow-up is 3 years. Trial pathologists were trained in histopathological assessment and reporting of the involvement of the CRM and plane of surgery (PoS) according to pre-set criteria describing the plane of dissection (Grade 1-muscularis plane: 2-intramesorectal plane: 3-mesorectal plane). 1232 patients were prospectively assessed for CRM and 1119 for PoS. Results: The CRM was involved (tumour ≤1mm) in 139 (11%) of resected specimens, and for these patients the 3-year local recurrence (LR), disease-free survival (DFS) and overall survival rates were 18%, 50% and 57%. For the 1093 patients with CRM-ve the respective rates were 7%, 81% and 84%. LR and DFS rates were associated with PoS (log-rank test p=0.0019 and p=0.0506 respectively), and in addition there was clear evidence of a reduction in LR and improvement in DFS rates in favour of PRE for all grades of quality of surgical assessment as shown in the table . Conclusions: The results indicate a strong association between the quality of surgery and the rates of local recurrence and disease-free survival, as well as a clear benefit from the addition of PRE to all grades of surgical dissection. Thus for patients with rectal cancer short-course pre-operative radiotherapy and good quality surgery can almost completely eliminate local recurrence.

[Table: see text]

No significant financial relationships to disclose.

Depressive and anxiety disorder comorbidity in obsessive compulsive disorder

BACKGROUND

Depressive and other anxiety disorders are commonly found to coexist with obsessive compulsive disorder (OCD). Although western studies have looked at this issue, there are no reports from India investigating anxiety and depressive comorbidity in adult OCD.

METHODS

Between January and December 2001, charts of 218 OCD patients seen in the OCD clinic at the National Institute of Mental Health and Neurosciences, Bangalore, were evaluated using the OPCRIT criteria for ICD-10 for the presence of comorbid depressive and anxiety disorders.

RESULTS

There were 146 males and 72 females; their mean age at OCD onset was 21.32 +/- 0.64 years. Thirty-six (16.5%) patients had depressive episodes, 12 (5.5%) dysthymia and 15 (6.9%) any anxiety disorder. No significant difference in terms of age, sex, marital status or age at onset was found between the OCD patients with and without comorbid anxiety disorder, major depression or dysthymia, except that female OCD patients were more likely than males to have comorbid major depressive disorder.

CONCLUSIONS

The results of our study are in keeping with previous data from other parts of the world, though the actual rates of comorbidity in our sample appear to be much lower. It remains to be seen whether the differences in rates are a result of methodological issues or different characteristics of sample populations. Further long-term, prospective, methodologically sound studies investigating the comorbidity of depressive and other anxiety disorders in OCD patients are needed to clarify this issue.