Review article: vitamin D and inflammatory bowel disease--established concepts and future directions

BACKGROUND

Understanding of the role of vitamin D in health and disease has increased markedly in the past decade, with its involvement extending well beyond traditional roles in calcium and phosphate homeostasis and musculoskeletal health. This conceptual expansion has been underpinned by identification and exploration of components of this axis including vitamin D-binding protein, key enzymes and receptors in multiple cell types, and a greater recognition of nonclassical autocrine and paracrine effects. Its influence in IBD remains uncertain.

AIM

To review the role of vitamin D in bone health, immune regulation and cancer prevention in IBD, and to outline practical issues and limitations of its use.

METHODS

An extensive online literature review including PubMed and Medline.

RESULTS

In patients with IBD, the vitamin D axis provides an important and often underutilised pathway to preserving bone health. Furthermore, an exciting body of clinical and basic science research demonstrates that these pathways may have an integral part to play in regulation of the immune response in IBD, through effects on the intestinal barrier, antigen presenting cells and adaptive T cells. The possibility of chemoprevention requires further study. The optimal target level of 25-hydroxy vitamin D in patients with IBD is currently uncertain, as is the best therapeutic modality.

CONCLUSIONS

Study of vitamin D pathways may result in the development of relatively inexpensive therapeutic options to optimise patient outcomes. Further prospective clinical research is required to address efficacy and long-term safety.

Eosinophilic mastitis masquerading as breast carcinoma

We report the sixth case of Eosinophilic Mastitis, presenting similarly enough to be confused with breast carcinoma. A 50 year old lady presented with a six month history of progressively enlarging asymptomatic breast lump, cough and breathlessness. Clinical examination, mammography and axillary lymphadenopathy suggested malignant disease. Ronchi were heard on chest auscultation. Needle cytology was twice inconclusive and Tru-cut biopsy showed acute on chronic inflammation. Blood investigations revealed significant peripheral eosinophilia. Open biopsy reported eosinophilic mastits, correlating with peripheral eosinophilia and pulmonary symptoms. The patient responded to conservative management. Eosinophilic infiltration of the breast is a rare manifestation of tissue involvement in peripheral eosinophilia. Asthma, Churgh-Strauss Syndrome and hyper-eosinophilic syndromes are associated. Importantly, if a clinically and radiologically malignant breast lump in asthmatic ladies with peripheral eosinophilia is not confirmed on cytology, this entity could be a diagnosis, potentially saving the patient from surgery.

Intense two-cycle laser pulses induce time-dependent bond hardening in a polyatomic molecule

A time-dependent bond-hardening process is discovered in a polyatomic molecule (tetramethyl silane, TMS) using few-cycle pulses of intense 800 nm light. In conventional mass spectrometry, symmetrical molecules such as TMS do not exhibit a prominent molecular ion (TMS(+)) as unimolecular dissociation into [Si(CH(3))(3)](+) proceeds very fast. Under a strong field and few-cycle conditions, this dissociation channel is defeated by time-dependent bond hardening: a field-induced potential well is created in the TMS(+) potential energy curve that effectively traps a wave packet. The time dependence of this bond-hardening process is verified using longer-duration (≥100 fs) pulses; the relatively slower falloff of optical field in such pulses allows the initially trapped wave packet to leak out, thereby rendering TMS(+) unstable once again.

Review article: the pathophysiological roles of the renin-angiotensin system in the gastrointestinal tract

BACKGROUND

The renin-angiotensin system (RAS) is a homeostatic pathway widely known to regulate cardiovascular and renal physiology; however, little is known about its influence in gastrointestinal tissues.

AIM

To elicit the anatomical distribution and physiological significance of the components of the RAS in the gastrointestinal tract.

METHODS

An extensive online literature review including Pubmed and Medline.

RESULTS

There is evidence for RAS involvement in gastrointestinal physiology and pathophysiology, with all the components required for autonomous regulation identified throughout the gastrointestinal tract. The RAS is implicated in the regulation of glucose, amino acid, fluid and electrolyte absorption and secretion, motility, inflammation, blood flow and possibly malignant disease within the gastrointestinal tract. Animal studies investigating the effects of RAS blockade in a range of conditions including inflammatory bowel disease, functional gut disorders, gastrointestinal malignancy and even intestinal ischaemia have been encouraging to date. Given the ready availability of drugs that modify the RAS and their excellent safety profile, an opportunity exists for investigation of their possible therapeutic role in a variety of human gastrointestinal diseases.

CONCLUSIONS

The gastrointestinal renin-angiotensin system appears to be intricately involved in a number of physiological processes, and provides a possible target for novel investigative and therapeutic approaches.

Bronchoscopic management of benign bronchial stenosis by electrocautery and balloon dilatation

Benign bronchial stenosis is managed by surgical or bronchoscopic methods. Although surgical approach is definitive, it is technically demanding and is costlier than bronchoscopic treatment. Here, we report the case of a 27-year-old female patient with symptomatic benign bronchial stenosis of the left main bronchus. The stenosis was dilated successfully through a fibreoptic bronchoscope by electrocautery followed by balloon bronchoplasty and application of mitomycin-C. On follow up, there was no evidence of re-stenosis.

AE9C90CB: a novel, bladder-selective muscarinic receptor antagonist for the treatment of overactive bladder

BACKGROUND AND PURPOSE

AE9C90CB (N- [(1R, 5S, 6R)-3-azabicyclo [3.1.0] hex-6-ylmethyl]-2-hydroxy-N-methyl-2, 2-diphenylacetamide), a novel muscarinic receptor antagonist, was synthesized for the treatment of overactive bladder. Here we describe the in vitro and in vivo profiles of AE9C90CB for action in bladder over salivary gland and compare it with four agents already in clinical use (tolterodine, oxybutynin, solifenacin and darifenacin).

EXPERIMENTAL APPROACH

Radioligand binding assay and isolated tissue-based functional assay were used to evaluate affinity, potency, and receptor subtype selectivity of compounds. Inhibition of carbachol-induced increase in intravesicular pressure and salivary secretion were measured in anaesthetized rabbits to assess the functional selectivity.

KEY RESULTS

In vitro radioligand binding study using human recombinant muscarinic receptors showed that AE9C90CB had greater affinity for M(3) muscarinic receptors with pKi of 9.90 +/- 0.11 and was 20-fold more selective for M(3) than for M(2) muscarinic receptors. AE9C90CB exhibited an unsurmountable antagonism on rat bladder strips (pK(B), 9.13 +/- 0.12). In anaesthetized rabbits after intravenous administration, AE9C90CB dose dependently inhibited carbachol-induced increase in intravesicular pressure and salivary secretion, and exhibited functional selectivity for urinary bladder over salivary gland which was ninefold better than that of oxybutynin.

CONCLUSIONS AND IMPLICATIONS

We have identified AE9C90CB, a compound exhibiting moderate selectivity for M(3) over M(2) receptors but greater selectivity for urinary bladder over salivary gland than oxybutynin, tolterodine, solifenacin and darifenacin. Therefore, AE9C90CB may be a promising compound for the treatment of overactive bladder with reduced potential to cause dry mouth than currently available antimuscarinic drugs.

Accuracy of amplitude integrated EEG in a neonatal cohort

OBJECTIVE

To determine the sensitivity and specificity of amplitude integrated electroencephalogram (aEEG) compared to simultaneous standard electroencephalogram (sEEG) for seizure detection and background discontinuity.

DESIGN

Prospective paired cohort.

SETTING

Tertiary academic neonatal intensive care unit.

PATIENTS

Infants were recruited from 2005 to 2008. Neonates requiring sEEG were recruited for simultaneous aEEG.

INTERVENTIONS

Following sEEG and aEEG, seizures were recorded as present or absent, and background was recorded as normal or discontinuous in each format.

MAIN OUTCOME MEASURES

Presence of at least one seizure during recording. The background activity was reported as normal or discontinuous. Discontinuity of brain activity was further ranked as mild, moderate or severe.

RESULTS

51 sEEG and aEEG studies were completed. 44 studies were analysed for presence of seizures and 46 were analysed for background discontinuity. Sensitivity for presence of seizures by aEEG was 80% and specificity was 50%. The proportion of infants with seizures were overdiagnosed by aEEG (63.6% vs 45.5% for sEEG p=0.045). Discontinuity of background activity had higher sensitivity (88.6%) and specificity (54.5%) when compared with seizure detection. When stratified by indication for EEG, hypoxic episode (n=14) or suspected seizures (n=33), similar sensitivity for presence of seizure (80%) was noted by aEEG and sEEG. However the specificity of aEEG for seizure detection was higher in neonates undergoing EEG for suspected seizures (66.7% vs 22.2%).

CONCLUSIONS

Background abnormalities were detected with fair accuracy by aEEG but aEEG criteria alone would result in the overdiagnosis of neonatal seizures. Therefore seizures noted on aEEG require sEEG confirmation prior to implementing anticonvulsant therapy for neonatal seizures.

Prevalence of obesity in Indian women

Comparison of two major studies conducted by National family health survey (NFHS-2) in 1998-1999 and NFHS-3 in 2005-2006 shows that prevalence of obesity among Indian women has elevated from 10.6% to 12.6% (increased by 24.52%). The prevalence is more profound in the women of age between 40-49 years (23.7%), residing in cities (23.5%), having high qualification (23.8%), belonging to Sikh community (31.6%) and households in the highest wealth quintile (30.5%). Highest percentage of obese women is found in Punjab (29.9%). Although this number seems small in the international perspective, it is significant because of the sheer size of population in India. While the problem of under-nutrition still exists in many parts of India, the additional burden of obesity due to increasing sedentary lifestyle, junk food habits in some urban and economically sound areas is really alarming. Prevention and control of this serious problem through awareness programmes to adopt diversified nutritional food and healthy lifestyle are strongly recommended.

Native aortic valve tissue systemic embolization complicating bacterial endocarditis

Systemic embolic events are known complications of bacterial endocarditis. Embolization of prosthetic valves has previously been reported in the literature. We report a case of embolization of native aortic valve tissue to the popliteal artery as the presenting event in a patient with subacute bacterial endocarditis. To our knowledge, this rare complication has not been previously reported.

Association between magnesium : iron intake ratio and diabetes in Chinese adults in Jiangsu Province

BACKGROUND

The intake of iron is positively related to the risk of diabetes, whilst magnesium intake is inversely related. However, it is unknown whether there is an interaction between dietary magnesium and iron expressed as a ratio and diabetes.

METHODS

This is a cross-sectional household survey carried out in 2002 in Jiangsu Province, China. A total of 2849 men and women aged >or = 20 years participated (participation rate 89.0%). Iron and magnesium intake was assessed by 3-day weighed food records. Fasting plasma glucose, serum ferritin and haemoglobin were measured.

RESULTS

The mean intake of iron and magnesium was 25 mg/day and 332 mg/day, respectively. The prevalence of diabetes was 3.0% in men and 2.6% in women. Magnesium intake was negatively associated with diabetes when adjusted for age and sex, but not in a fully adjusted model. A strong inverse association between magnesium : iron intake ratio and diabetes was observed. In the fully adjusted model, the odds ratios of diabetes across quartiles of magnesium : iron intake ratio were: 1.0, 0.63 [95% confidence interval 0.32-1.25], 0.36 (0.16-0.81) and 0.48 (0.20-1.14) (P for trend 0.038). There was an interaction between central obesity and magnesium : iron ratio.

CONCLUSION

Magnesium : iron intake ratio is an independent risk marker for diabetes in Chinese adults. As this is a cross-sectional study, we cannot establish any causal relationship.