The NF-κB signaling system in the immunopathogenesis of inflammatory bowel disease

Inflammatory bowel disease (IBD) is an idiopathic, chronic condition characterized by episodes of inflammation in the gastrointestinal tract. The nuclear factor κB (NF-κB) system describes a family of dimeric transcription factors. Canonical NF-κB signaling is stimulated by and enhances inflammation, whereas noncanonical NF-κB signaling contributes to immune organogenesis. Dysregulation of NF-κB factors drives various inflammatory pathologies, including IBD. Signals from many immune sensors activate NF-κB subunits in the intestine, which maintain an equilibrium between local microbiota and host responses. Genetic association studies of patients with IBD and preclinical mouse models confirm the importance of the NF-κB system in host defense in the gut. Other studies have investigated the roles of these factors in intestinal barrier function and in inflammatory gut pathologies associated with IBD. NF-κB signaling modulates innate and adaptive immune responses and the production of immunoregulatory proteins, anti-inflammatory cytokines, antimicrobial peptides, and other tolerogenic factors in the intestine. Furthermore, genetic studies have revealed critical cell type-specific roles for NF-κB proteins in intestinal immune homeostasis, inflammation, and restitution that contribute to the etiopathology of IBD-associated manifestations. Here, we summarize our knowledge of the roles of these NF-κB pathways, which are activated in different intestinal cell types by specific ligands, and their cross-talk, in fueling aberrant intestinal inflammation. We argue that an in-depth understanding of aberrant immune signaling mechanisms may hold the key to identifying predictive or prognostic biomarkers and developing better therapeutics against inflammatory gut pathologies.

Scientific advisory on nocturnal hypoglycemia in insulin-treated patients with diabetes: Recommendations from Indian experts

INTRODUCTION

Insulin is one of the commonly prescribed glucose lowering agents in diabetes. Hypoglycemia is the most common complication, and severe hypoglycemia is the most serious complication of insulin therapy. Almost half of all severe hypoglycemia episodes (HEs) occur at night. However, patients are often unaware of their nocturnal hypoglycaemia (NH) risk. Additionally, both healthcare professionals and patients find it difficult to manage NH. The purpose of this expert group meeting is to improve NH awareness and provide guidance for the physicians to recognize and manage NH.

METHOD

The panel of experts in an e-board deliberated extensively upon the available literature and guidelines on hypoglycemia and NH discussed the consensus on definition, detection, reporting, monitoring, treatment, and optimization of therapy in NH.

RESULT

& Conclusion: Though there are many guidelines on the management of HEs in patients with diabetes, very few touch the topic of NH. This scientific advisory on management of NH in insulin treated patients with diabetes is formulated to address this gap in understanding regarding management of NH. The experts provide recommendations for the nocturnal window, defining NH based on blood glucose values, recognition, prevention and management of NH.

988 A Quality Improvement Project; Improving the Quality and Safety of Handover During COVID-19

Aim

The World Health Organisation (WHO) positions effective handover, in its top five patient safety solutions. During our District Hospital Trust’s COVID-19 response, an unprecedented reorganisation of all teams occurred. All surgical and medical speciality junior doctors were re-deployed and split into 4 zones to cover the hospital. In this quality improvement project (QIP), we sought to understand our trainees’ thoughts on this new multi-zonal handover process and aimed to identify risk-reduction measures to aid better patient care.

Method

The opinions of trainees on the new handover system were obtained using an online Likert scale survey. Following the responses, a new morning and night handover proforma was developed. This was used trust-wide and a post-intervention repeat survey was conducted to assess the new changes.

Results

The primary survey received 31 responses with feedback illustrating mixed effectiveness of the existing handover process. Free text comments highlighted issues surrounding “safety”, “poor organisation”, “poor continuity of care” with one serious incident reported. Post-intervention of a new handover proforma, a repeat online survey received 25 responses. Results were significantly more positive with >84% of responses being in the “strongly agree to agree” category, including for “continuity of care”, “organisation”, and “safety”.

Conclusions

This QIP illustrates a good example of a low-cost intervention to create a better handover system and aid hospitals during time of crises. For us, it managed to reform the handover process and ultimately improved our patient care. Forthcoming, we would like to create a national best practice guide for effective handover.

1613 A Case Study Implementing A Strength Training Programme with The Aim to Reduce the Risk of Osteosarcopenia And Bone Fractures

Aim

Strength training induces a mechanical load, both increasing muscle mass and enhancing osteoblast activity. This results in increased muscle and bone strength, reducing the risk of osteosarcopenia. Osteosarcopenia can start after the age of 30, putting patients at increased risk of bone fractures, with an untrained individual losing 0.23kg of muscle mass per year. In this case study, we illustrate a training programme, implemented over a period of 4 weeks on an untrained individual. The aim is to set an exemplar strengthening regimen for patients to reduce their risk of developing osteosarcopenia and bone fractures.

Method

One untrained novice subject was recruited. Two physical profile measurements were taken, prior to the start of the programme and at its conclusion. These included height, weight, BMI, lean body mass, muscle circumference and 1 repetition max (1RM) for upper body strength (bench press) and lower body strength (deadlift and squat).

Results

The subject had increased strength performance with increased 1RM, or equivalent, in the deadlift (+2.9kg), squat (+3kg) and bench press (+2.5kg) He also had a small increase in lean body mass of 0.1kg and increased body circumference in all muscle groups.

Conclusions

Our study shows that a simple strength training programme performed independently can lead to improved muscle strength and increased lean body mass. We illustrated that the programme can be performed inexpensively. Forthcoming, we would like to perform a prospective cohort study with the aim to implement a standardised programme within national guidelines for fracture risk-reduction.

An epithelial Nfkb2 pathway exacerbates intestinal inflammation by supplementing latent RelA dimers to the canonical NF-κB module

Aberrant inflammation, such as that associated with inflammatory bowel disease (IBD), is fueled by the inordinate activity of RelA/NF-κB factors. As such, the canonical NF-κB module mediates controlled nuclear activation of RelA dimers from the latent cytoplasmic complexes. What provokes pathological RelA activity in the colitogenic gut remains unclear. The noncanonical NF-κB pathway typically promotes immune organogenesis involving Nfkb2 gene products. Because NF-κB pathways are intertwined, we asked whether noncanonical signaling aggravated inflammatory RelA activity. Our investigation revealed frequent engagement of the noncanonical pathway in human IBD. In a mouse model of experimental colitis, we established that Nfkb2-mediated regulations escalated the RelA-driven proinflammatory gene response in intestinal epithelial cells, exacerbating the infiltration of inflammatory cells and colon pathologies. Our mechanistic studies clarified that cell-autonomous Nfkb2 signaling supplemented latent NF-κB dimers, leading to a hyperactive canonical RelA response in the inflamed colon. In sum, the regulation of latent NF-κB dimers appears to link noncanonical Nfkb2 signaling to RelA-driven inflammatory pathologies and may provide for therapeutic targets.

Role of the NF-κB system in context-specific tuning of the inflammatory gene response

The canonical NF-κB pathway instructs the expression of inflammatory genes by the RelA:p50 transcription factor in response to diverse cell-activating stimuli. However, this mainstay RelA:p50 transcriptional output must also be curated so as to provide for stimulus-type-specific and cell-type-specific inflammatory responses adapted to the local tissue-microenvironment. Here, we summarize the fundamental mechanisms regulating RelA:p50-mediated gene expressions and discuss how the NF-κB system imparts specificity in the inflammatory gene program. We put forward a conceptual framework where the dynamical attributes and the composition of the nuclear NF-κB complexes cumulatively instruct context-specific inflammatory gene patterns. We propose that integrating mechanistic knowledge and systems-level analyses may offer further insights on NF-κB-mediated inflammatory gene control in the future.

Unravelling the utility of modern sulfonylureas from cardiovascular outcome trials and landmark trials: expert opinion from an international panel

AIM

The primary objective of this review is to develop practice-based expert group opinions on the cardiovascular (CV) safety and utility of modern sulfonylureas (SUs) in cardiovascular outcome trials (CVOTs).

BACKGROUND

The United States Food and Drug Administration issued new guidance to the pharmaceutical industry in 2008 regarding the development of new antihyperglycemic drugs. The guidance expanded the scope for the approval of novel antihyperglycemic drugs by mandating CVOTs for safety. A few long-term CVOTs on dipeptidyl peptidase 4 inhibitors, glucagon-like peptide 1 receptor agonists, and sodium-glucose cotransporter 2 inhibitors have been completed, while others are ongoing. SUs, which constitute one of the key antihyperglycemic agents used for the management of type 2 diabetes mellitus (T2DM), have been used as comparator agents in several CVOTs. However, the need for CVOTs on modern SUs remains debatable. In this context, a multinational group of endocrinologists convened for a meeting and discussed the need for CVOTs of modern SUs to evaluate their utility in the management of patients with T2DM. At the meeting, CVOTs of modern SUs conducted to date and the hypotheses derived from the results of these trials were discussed.

REVIEW RESULTS

The expert group analyzed the key trials emphasizing the CV safety of modern SUs and also reviewed the results of various CVOTs in which modern SUs were used as comparators. Based on literature evidence and individual clinical insights, the expert group opined that modern SUs are cardiosafe and that since they have been used as comparators in other CVOTs, CVOTs of SUs are not required.

CONCLUSION

Modern SUs can be considered a cardiosafe option for the management of patients with diabetes mellitus and CV disease; thus CVOTs among individuals with T2DM are not required.

Role of NF-kappaB2-p100 in regulatory T cell homeostasis and activation

The immunological roles of the nuclear factor-kappaB (NF-κB) pathway are mediated via the canonical components in immune responses and via non-canonical components in immune organogenesis and homeostasis, although the two components are capable of crosstalk. Regulatory CD4 T cells (Tregs) are homeostatically functional and represent an interesting potential meeting point of these two NF-κB components. We show that mice deficient in the non-canonical NF-κB component gene Nfkb2 (p100) had normal thymic development and suppressive function of Tregs. However, they had enhanced frequencies of peripheral ‘effector-phenotype’ Tregs (eTregs). In bi-parental chimeras of wild-type (WT) and Nfkb2−/− mice, the Nfkb2−/− genotype was over-represented in Tregs, with a further increase in the relative prominence of eTregs. Consistent with distinct properties of eTregs, the Nfkb2−/− genotype was more prominent in Tregs in extra-lymphoid tissues such as liver in the bi-parental chimeras. The Nfkb2−/− Tregs also displayed greater survival, activation and proliferation in vivo. These Nfkb2−/− Tregs showed higher nuclear NF-κB activity mainly comprising of RelB-containing dimers, in contrast to the prominence of cRel- and RelA-containing dimers in WT Tregs. Since p100 is an inhibitor of RelB activation as well as a participant as cleaved p52 in RelB nuclear activity, we tested bi-parental chimeras of WT and Relb−/− mice, and found normal frequencies of Relb−/− Tregs and eTregs in these chimeric mice. Our findings confirm and extend recent data, and indicate that p100 normally restrains RelB-mediated Treg activation, and in the absence of p100, p50-RelB dimers can contribute to Treg activation.

Immune Differentiation Regulator p100 Tunes NF-κB Responses to TNF

Tumor necrosis factor (TNF) is a pleiotropic cytokine whose primary physiological function involves coordinating inflammatory and adaptive immune responses. However, uncontrolled TNF signaling causes aberrant inflammation and has been implicated in several human ailments. Therefore, an understanding of the molecular mechanisms underlying dynamical and gene controls of TNF signaling bear significance for human health. As such, TNF engages the canonical nuclear factor kappa B (NF-κB) pathway to activate RelA:p50 heterodimers, which induce expression of specific immune response genes. Brief and chronic TNF stimulation produces transient and long-lasting NF-κB activities, respectively. Negative feedback regulators of the canonical pathway, including IκBα, are thought to ensure transient RelA:p50 responses to short-lived TNF signals. The non-canonical NF-κB pathway mediates RelB activity during immune differentiation involving p100. We uncovered an unexpected role of p100 in TNF signaling. Brief TNF stimulation of p100-deficient cells triggered an additional late NF-κB activity consisting of RelB:p50 heterodimers, which modified the TNF-induced gene-expression program. In p100-deficient cells subjected to brief TNF stimulation, RelB:p50 not only sustained the expression of a subset of RelA-target immune response genes but also activated additional genes that were not normally induced by TNF in WT mouse embryonic fibroblasts (MEFs) and were related to immune differentiation and metabolic processes. Despite this RelB-mediated distinct gene control, however, RelA and RelB bound to mostly overlapping chromatin sites in p100-deficient cells. Repeated TNF pulses strengthened this RelB:p50 activity, which was supported by NF-κB-driven RelB synthesis. Finally, brief TNF stimulation elicited late-acting expressions of NF-κB target pro-survival genes in p100-deficient myeloma cells. In sum, our study suggests that the immune-differentiation regulator p100 enforces specificity of TNF signaling and that varied p100 levels may provide for modifying TNF responses in diverse physiological and pathological settings.

A TNF-p100 pathway subverts noncanonical NF-κB signaling in inflamed secondary lymphoid organs

Lymphotoxin-beta receptor (LTβR) present on stromal cells engages the noncanonical NF-κB pathway to mediate RelB-dependent expressions of homeostatic chemokines, which direct steady-state ingress of naïve lymphocytes to secondary lymphoid organs (SLOs). In this pathway, NIK promotes partial proteolysis of p100 into p52 that induces nuclear translocation of the RelB NF-κB heterodimers. Microbial infections often deplete homeostatic chemokines; it is thought that infection-inflicted destruction of stromal cells results in the downregulation of these chemokines. Whether inflammation per se also regulates these processes remains unclear. We show that TNF accumulated upon non-infectious immunization of mice similarly downregulates the expressions of these chemokines and consequently diminishes the ingress of naïve lymphocytes in inflamed SLOs. Mechanistically, TNF inactivated NIK in LTβR-stimulated cells and induced the synthesis of Nfkb2 mRNA encoding p100; these together potently accumulated unprocessed p100, which attenuated the RelB activity as inhibitory IκBδ. Finally, a lack of p100 alleviated these TNF-mediated inhibitions in inflamed SLOs of immunized Nfkb2-/- mice. In sum, we reveal that an inhibitory TNF-p100 pathway modulates the adaptive compartment during immune responses.

Developing indicators for evaluation of age-friendly communities in Canada: process and results

INTRODUCTION

In 2006, the World Health Organization launched the Global Age-Friendly Cities Project to support active aging. Canada has a large number of age-friendly initiatives; however, little is known about the effectiveness and outcomes of age-friendly community (AFC) initiatives. In addition, stakeholders report that they lack the capacity and tools to develop and conduct evaluations of their AFC initiatives. In order to address these gaps, the Public Health Agency of Canada developed indicators to support the evaluation of AFC initiatives relevant to a wide range of Canadian communities. These indicators meet the varied needs of communities, but are not designed to evaluate collective impact or enable crosscommunity comparisons.

METHODS

An evidence-based, iterative consultation approach was used to develop indicators for AFCs. This involved a literature review and an environmental scan. Two rounds of key expert and stakeholder consultations were conducted to rate potential indicators according to their importance, actionability and feasibility. A final list of indicators and potential measures were developed based on results from these consultations, as well as key policy considerations.

RESULTS

Thirty-nine indicators emerged across eight AFC domains plus four indicators related to long-term health and social outcomes. All meet the intended purpose of evaluating AFC initiatives at the community level. A user-friendly guide is available to support and share this work.

CONCLUSION

The AFC indicators can help communities evaluate age-friendly initiatives, which is the final step in completing a cycle of the Pan-Canadian AFC milestones. Communities are encouraged to use the evaluation results to improve their AFC initiatives, thereby benefiting a broad range of Canadians.

Chromosome Specific Substitution Lines of Aegilops geniculata Alter Parameters of Bread Making Quality of Wheat

Wheat cultivars with wide introgression have strongly impacted global wheat production. Aegilops geniculata (M^gU^g) is an important wild relative with several useful traits that can be exploited for wheat improvement. Screening of Ae. geniculata addition lines indicated a negative effect of 1U^g and the positive effect of 1M^g chromosome on wheat dough strength. Negative effect of 1U^g is probably associated with variation in number and position of the tripeptide repeat motif in the high molecular weight glutenin (HMW-G) gene. To utilize the positive potential of 1M^g chromosome, three disomic substitution lines (DSLs) 1M^g(1A), 1M^g(1B) and 1M^g(1D) were created. These lines were characterized for morphological, cytogenetic properties and biochemical signatures using FISH, 1D-, 2D-PAGE and RP-HPLC. Contribution of wheat 1A, 1B and 1D chromosomes towards dough mixing and baking parameters, chapatti quality, Fe/Zn content and glume color were identified. Observed order of variation in the dough mixing and baking parameters {1M^g(1D) ≤wheat ≤1M^g(1B) ≤1M^g(1A)} indicated that chromosome specific introgression is desirable for best utilization of wild species’ potential.

The Chromosomal parDE2 Toxin-Antitoxin System of Mycobacterium tuberculosis H37Rv: Genetic and Functional Characterization

Mycobacterium tuberculosis H37Rv escapes host-generated stresses by entering a dormant persistent state. Activation of toxin-antitoxin modules is one of the mechanisms known to trigger such a state with low metabolic activity. M. tuberculosis harbors a large number of TA systems mostly located within discernible genomic islands. We have investigated the parDE2 operon of M. tuberculosis H37Rv encoding MParE2 toxin and MParD2 antitoxin proteins. The parDE2 locus was transcriptionally active from growth phase till late stationary phase in M. tuberculosis. A functional promoter located upstream of parD2 GTG start-site was identified by 5'-RACE and lacZ reporter assay. The MParD2 protein transcriptionally regulated the P parDE2 promoter by interacting through Arg16 and Ser15 residues located in the N-terminus. In Escherichia coli, ectopic expression of MParE2 inhibited growth in early stages, with a drastic reduction in colony forming units. Live-dead analysis revealed that the reduction was not due to cell death alone but due to formation of viable but non-culturable cells (VBNCs) also. The toxic activity of the protein, identified in the C-terminal residues Glu98 and Arg102, was neutralized by the antitoxin MParD2, both in vivo and in vitro. MParE2 inhibited mycobacterial DNA gyrase and interacted with the GyrB subunit without affecting its ATPase activity. Introduction of parE2 gene in the heterologous M. smegmatis host prevented growth and colony formation by the transformed cells. An M. smegmatis strain containing the parDE2 operon also switched to a non-culturable phenotype in response to oxidative stress. Loss in colony-forming ability of a major part of the MParE2 expressing cells suggests its potential role in dormancy, a cellular strategy for adaptation to environmental stresses. Our study has laid the foundation for future investigations to explore the physiological significance of parDE2 operon in mycobacterial pathogenesis.

Soft and Hard Textured Wheat Differ in Starch Properties as Indicated by Trimodal Distribution, Morphology, Thermal and Crystalline Properties

Starch and proteins are major components in the wheat endosperm that affect its end product quality. Between the two textural classes of wheat i.e. hard and soft, starch granules are loosely bound with the lipids and proteins in soft wheat due to higher expression of interfering grain softness proteins. It might have impact on starch granules properties. In this work for the first time the physiochemical and structural properties of different sized starch granules (A-, B- and C-granules) were studied to understand the differences in starches with respect to soft and hard wheat. A-, B- and C-type granules were separated with >95% purity. Average number and proportion of A-, B-, and C-type granules was 18%, 56%, 26% and 76%, 19%, 5% respectively. All had symmetrical birefringence pattern with varied intensity. All displayed typical A-type crystallites. A-type granules also showed V-type crystallinity that is indicative of starch complexes with lipids and proteins. Granules differing in gelatinization temperature (ΔH) and transition temperature (ΔT), showed different enthalpy changes during heating. Substitution analysis indicated differences in relative substitution pattern of different starch granules. Birefringence, percentage crystallinity, transmittance, gelatinization enthalpy and substitution decreased in order of A>B>C being higher in hard wheat than soft wheat. Amylose content decreased in order of A>B>C being higher in soft wheat than hard wheat. Reconstitution experiment showed that starch properties could be manipulated by changing the composition of starch granules. Addition of A-granules to total starch significantly affected its thermal properties. Effect of A-granule addition was higher than B- and C-granules. Transmittance of the starch granules paste showed that starch granules of hard wheat formed clear paste. These results suggested that in addition to differences in protein concentration, hard and soft wheat lines have differences in starch composition also.

A founder mutation p.H701P identified as a major cause of SPG7 in Norway

BACKGROUND AND PURPOSE

SPG7 is one of the most common forms of autosomal recessive hereditary spastic paraplegia. The phenotype has been shown to be heterogeneous, varying from a complex spastic ataxia to pure spastic paraplegia or pure ataxia. The aim of this study was to clinically and genetically characterize patients with SPG7 in Norway.

METHODS

Six Norwegian families with a clinical diagnosis of hereditary spastic paraplegia were diagnosed with SPG7 through Sanger sequencing and whole-exome sequencing. Haplotypes were established to identify a possible founder mutation. All patients were thoroughly examined and the clinical and molecular findings are described.

RESULTS

The core phenotype was spastic paraparesis with ataxia, bladder disturbances and progressive external ophthalmoplegia. The variant p.H701P was identified in homozygous state in one family and in compound heterozygous state in three families. Haplotype analysis of seven surrounding single nucleotide polymorphisms supports that this variant resides on a founder haplotype. Four of the families were compound heterozygous for the previously well-described p.A510V variant.

CONCLUSION

SPG7 is a common subgroup of hereditary spinocerebellar disorders in Norway. The broad phenotype in the Norwegian SPG7 population illustrates the challenges with the traditional dichotomous classification of hereditary spinocerebellar disorders into hereditary spastic paraplegia or hereditary ataxia. A Norwegian founder mutation p.H701P was identified in four out of six families, making it a major cause of SPG7 in Norway.

Non-alcoholic fatty liver disease (NAFLD)--the hepatic component of metabolic syndrome

AIMS

To study the prevalence of NAFLD in those patients attending the routine health checkup and to establish a relationship between NAFLD and metabolic syndrome.

PATIENTS AND METHODS

All patients attending the health check-up had their blood pressure, height and weight, waist circumference measurements, blood sugars, lipid levels and ultrasound abdomen done. The prevalence of NAFLD among these subjects was determined and the presence of risk factors for metabolic disease in each individual was analysed. A relationship between NAFLD and metabolic syndrome was then established.

RESULTS

Of the 1003 people 225 (22.6%) had NAFLD with higher prevalence among males 164/565 (29%) than among females 61/438 (13.9%). In the NAFLD group normal body mass index (BMI) was present in only 49/225 (20%) of the subjects while 119/225 (52.8%) were overweight and 56/225 (24.8%) were obese. Though liver enzymes were normal the mean AST among cases was 37.41 +/- 14.50 and 33.93 +/- 14.15 among controls and the mean ALT was 38.74 +/- 17.96 among cases and 31.62 +/- 13.49 among controls. Prevalence of metabolic syndrome was 106/225 (47%) among cases and 179/778 (23%) among controls.

CONCLUSION

A diagnosis of fatty liver on ultrasound in an asymptomatic person should alert us of metabolic syndrome and its progression to cardiovascular disease. NAFLD may be considered as the hepatic component of metabolic syndrome.

Designer insulins regimens in clinical practice--pilot multicenter Indian study

BACKGROUND

Newer insulin analogues viz., premix insulin analogue (biphasic insulin aspart) and insulin glargine are now available in India. A multicenter all-India study was done to document the patient profile and responses to these analogues in routine clinical practice.

METHODS

The study was conducted prospectively at 4 diabetes care clinics in different regions of India and collected data on the use of either of the two regimens A. Premix insulin analogue given twice-daily B. Basal-bolus analogue regimen (insulin aspart with every meal and insulin glargine once-a-day at bedtime). The centers collected all data at 3 time-points--baseline, 4 weeks later and end of 12 weeks. The study measures were FPG (fasting plasma glucose), PPPG (postprandial plasma glucose), HbA1c and insulin dose. FPG and PPPG were recorded at each of the three time points. HbA1c was recorded at baseline and end of study. Safety was assessed based on reported adverse drug reactions and occurrence of hypoglycaemias.

RESULTS

Data of 145 patients was available for analysis (n=114 on premix insulin analogue and n=31 on basal-bolus analogue regimen). Baseline demography was comparable in the two groups. Both the regimens lowered all blood glucose parameters including HbA1c significantly as compared to baseline. However, the premix insulin analogue fared better than the basal-bolus regimen in lowering HbA1c (1.58 vs. 1.16% respectively; p<0.05). Also 41% more patients in the premix group could achieve target HbA1c of < 7% at the end of study. The mean insulin dose was lower with the premix analogue group at the end of 12 weeks. There was no significant difference between the two groups in terms of change in body weight. No major hypoglycaemias were reported and the percentage of patients experiencing a minor episode was lower with the premix analogue than the basal-bolus regimen both at 4 and 12 weeks (11.4 vs. 35.48%; 16.7 vs. 58.06% respectively). No adverse drug reactions were reported throughout the study.

CONCLUSION

We conclude that both premix analogue administered twice a day and four times a day basal bolus regimen appear to be a convenient, safe and effective way of initiating insulin therapy in people with type-2 diabetes. The premix analogues achieves target better than the basal bolus regimen as has better compliance.

Allodynia and hyperalgesia produced by specific inhibition of spinal c-fos expression: lack of correlation with dynorphin content

Inhibition of spinal Fos expression increases formalin-induced nociception and decreases spinal prodynorphin messenger ribonucleic acid (mRNA), suggesting that Fos modulates nociception by inducing dynorphin synthesis. This study tests the hypothesis that Fos modulates sensitivity to other somatic stimuli, such that inhibition of Fos expression will result in tactile allodynia and thermal hyperalgesia. In addition, it correlates the somatosensory effects of inhibition of Fos expression with spinal dynorphin content. Antisense oligodeoxynucleotide (ODN) to c-fos mRNA was administered by intrathecal infusion. Tactile sensitivity was tested by probing the hindpaw with von Frey filaments. Thermal sensitivity was quantitated by using withdrawal latency to radiant heat. Two percent formalin was injected into the dorsal hindpaw, and flinches were quantitated. Fos was quantitated by counting immunoreactive cells. Dynorphin was measured by immunoassay. Intrathecal antisense, but not mismatch, ODN resulted in tactile allodynia, thermal hyperalgesia, and hyperalgesia to formalin-induced nociception. Antisense ODN decreased Fos-like immunoreactivity after formalin injection but did not alter Jun-like immunoreactivity. Antisense ODN had differing effects on spinal dynorphin content, depending on the method of administration. These experiments show a role of Fos in modulating somatosensory sensitivity and suggest that induction of dynorphin synthesis is not the sole mechanism by which Fos does so.

Dermatology Life Quality Index: influence of an illustrated version

BACKGROUND

An illustrated version of the Dermatology Life Quality Index (DLQI) was developed in order to improve the ease with which this standard questionnaire is answered.

OBJECTIVES

To compare the illustrated version with the text-only version of the DLQI.

METHODS

The two versions were administered to 206 patients attending Dermatology outpatient clinics. The time taken to complete either the illustrated or the text-only version was noted in 52 additional patients.

RESULTS

One hundred and ninety-one of 206 patients completed both questionnaires satisfactorily. Their mean DLQI scores were 6.4 (median 4.0, lower quartile 1.0, upper quartile 11.0) for the illustrated version and 6.3 (median 4.0, lower quartile 1.0, upper quartile 10.0) for the text-only version. For the 98 patients who answered the illustrated version first, the mean DLQI scores were 6.9 (median 4.0, lower quartile 1.9, upper quartile 11.9) for the illustrated version and 6.4 (median 4.0, lower quartile 1.8, upper quartile 11.0) for the text-only version. For the 93 patients who answered the text-only version first, the mean DLQI scores were 5.9 (median 4.0, lower quartile 1.7, upper quartile 10.2) for the illustrated version and 6.2 (median 5.0, lower quartile 0.5, upper quartile 9.5) for the text-only version. The median time taken to complete the text-only version was 124 s (mean +/- SD 126 +/- 65, n = 27) and 88 s (mean +/- SD 101 +/- 52, n = 25) for the illustrated version (P = 0.08). There was a very close correlation (r = 0.98) between the scores of the text-only and the illustrated versions; 82.2% of patients either scored the same or had a DLQI score difference of only 1. One hundred and seven (59.8%) patients preferred using the illustrated version and 66 (36.9%) preferred the text-only version. One hundred and four (57.5%) found the illustrated version easier to use.

CONCLUSIONS

The illustrated version was superior to the text-only version in terms of patient preference and ease of use, but it was not possible to demonstrate exact equivalence between the two versions.

Chitosan: some pharmaceutical and biological aspects--an update

Chitosan, a natural polysaccharide, is being widely used as a pharmaceutical excipient. It is obtained by the partial deacetylation of chitin, the second most abundant natural polymer. Chitosan comprises a series of polymers varying in their degree of deacetylation, molecular weight, viscosity, pKa etc. The presence of a number of amino groups permit chitosan to chemically react with anionic systems, thereby resulting in alteration of physicochemical characteristics of such combinations. Chitosan has found wide applicability in conventional pharmaceutical devices as a potential formulation excipient, some of which include binding, disintegrating and tablet coating properties. The polymer has also been investigated as a potential adjuvant for swellable controlled drug delivery systems. Use of chitosan in novel drug delivery as mucoadhesive, gene and peptide drug administration via the oral route as well as its absorption enhancing effects have been explored by a number of researchers. Chitosan exhibits myriad biological actions, namely hypocholesterolemic, antimicrobial and wound healing properties. Low toxicity coupled with wide applicability makes it a promising candidate not only for the purpose of drug delivery for a host of drug moieties (antiinflammatories, peptides etc.) but also as a biologically active agent. It is the endeavour of the present review to provide an insight into the biological and pharmaceutical profile of chitosan. Various investigations carried out recently are reported, although references to research performed on chitosan prior to the recent reviews have also been included, where appropriate.

Enhancement of neointima formation with tissue-type plasminogen activator

PURPOSE

Indirect evidence suggests that tissue plasminogen activator (tPA) either limits or does not alter restenosis. However, tPA enhances tumor invasiveness through matrix remodeling, and several elements of degraded matrix enhance smooth muscle cell mitogenesis. We use either local adenoviral-mediated overexpression of tPA or systemic infusion of recombinant tPA combined with mechanical overdilation of rabbit common femoral arteries to evaluate the impact of tPA on neointima formation.

METHODS

Left common femoral arteries of New Zealand white rabbits were transfected in situ either with an adenoviral-construct-expressing tPA or a viral control (adenoviral-construct-expressing beta-galactosidase) or nonviral (buffer) control after balloon angioplasty injury. At 7 and 28 days, left common femoral artery segments were harvested (n = 4 for each group and time point). Vessel segments were examined for intimato-media ratio, smooth muscle cell proliferation, extracellular matrix, and inflammatory response. Thrombus formation was evaluated after 3 days (n = 3 for each group). In a second experiment, New Zealand white rabbits (n = 3 per group, per time point) underwent mechanical dilation followed by buffer treatment or systemic tPA infusion according to a widely clinically used accelerated infusion protocol. Treated artery segments were harvested after 7 or 28 days and processed for intima-to-media ratio determination and class-wide histochemical determination of collagenous extracellular matrix and collagen content.

RESULTS

Both rate and degree of neointima formation increase dramatically with overexpression (250%-461% relative to controls at 7 and 28 days). Substantial early matrix degradation is observed in vessels treated with local overexpression of tPA, although no increases in local inflammation or in smooth muscle proliferation occur. Late enhancement of smooth muscle proliferation emerges, consistent with secondary impact of perturbed matrix components. Systemic infusion of tPA according to clinical protocols also results in early and late enhancement of neointima formation in this model (34%-52% relative to controls at at 7 and 28 days), with significant early collagenous matrix degradation. Systemic infusion, although significant, did not attain the degree of neointima formation present with overexpression.

CONCLUSION

With some evidence of dose-dependence, tissue plasminogen activator enhances neointima formation after angioplasty in a rabbit model. Early matrix degradation precedes change in rates of proliferation and underlies this effect in spite of several antirestenotic actions including decreased thrombus and decreased macrophage recruitment in this model.

Potential applications of carbomer in oral mucoadhesive controlled drug delivery system: a review

Carbomers are extensively being used in controlled drug delivery systems (CDDS). They are also finding numerous applications in oral mucoadhesive drug delivery because of their ability to interact with the mucus glycoprotein and to remain localized to a specific site. The present review aims at giving an insight into the potential application of carbomers in mucoadhesive CDDS. This review deals with the physicochemical properties of carbomers and various mechanisms of mucoadhesion. The mechanism for the release of the drug, both water soluble and water insoluble, is discussed. The use of carbomers in oral delivery of peptides or protein-based drugs is also covered.

Thrombomodulin overexpression to limit neointima formation

BACKGROUND-These studies were initiated to confirm that high-level thrombomodulin overexpression is sufficient to limit neointima formation after mechanical overdilation injury. METHODS AND RESULTS-An adenoviral construct expressing thrombomodulin (Adv/RSV-THM) was created and functionally characterized in vitro and in vivo. The impact of local overexpression of thrombomodulin on neointima formation 28 days after mechanical overdilation injury was evaluated. New Zealand White rabbit common femoral arteries were treated with buffer, viral control, or Adv/RSV-THM and subjected to mechanical overdilation injury. The treated vessels (n=4 per treatment) were harvested after 28 days and evaluated to determine intima-to-media (I/M) ratios. Additional experiments were performed to determine early (7-day) changes in extracellular elastin and collagen content; local macrophage, T-cell, and neutrophil infiltration; and local thrombus formation as potential contributors to the observed impact on 28-day neointima formation. The construct significantly decreased neointima formation after mechanical dilation injury in this model. By histological analysis, buffer controls exhibited mean I/M ratios of 0.76+/-0.06%, whereas viral controls reached 0.77+/-0.08%; in contrast, Adv/RSV-THM reduced I/M ratios to 0.47+/-0.06%. Local inflammatory infiltrate decreased in the Adv/RSV-THM group relative to controls, whereas matrix remained relatively preserved. Rates of early thrombus formation also decreased in Adv/RSV-THM animals. CONCLUSIONS-This construct thus offers a viable technique for promoting a locally neointima-resistant small-caliber artery via decreased thrombus bulk, normal matrix preservation, and decreased local inflammation without the inflammatory damage that has limited many other adenoviral applications.

Nimesulide: some pharmaceutical and pharmacological aspects--an update

Nimesulide, a non-steroidal anti-inflammatory drug (NSAID), is administered orally or rectally twice daily for a variety of inflammation and pain states. This is a unique NSAID, not only because of its chemical structure but also because of its specific affinity to inhibit cyclooxygenase-2 (COX-2), thus exerting milder effects on the gastrointestinal mucosa. Current data on selective COX-2 inhibitors suggest that they may have an efficacy similar to that of standard NSAIDs. Initial general clinical experience with selective COX-2 inhibitors appears to show that they are particularly promising in individuals at risk because of renal diseases, hypertension or congestive heart failure. Various experimental models and clinical studies have demonstrated the anti-inflammatory efficacy of nimesulide. Nimesulide is superior, or at least comparable in efficacy, to other NSAIDs, but is better tolerated and has less potential for adverse reactions. Thus, selective COX-2 inhibitors should have anti-inflammatory effects devoid of side effects on the kidney and stomach. They may also demonstrate new important therapeutic benefits as anticancer agents as well as help prevention of premature labour and even retard the progression of Alzheimer's disease. No clinically significant drug interactions have been reported for nimesulide. Not much has been reported about the pharmaceutical aspects of nimesulide. Its poor aqueous solubility poses bioavailability problems in-vivo. This could be overcome by the formation of inclusion complexes with beta-cyclodextrin, as has been reported by various researchers. However, absence of any in-vivo data regarding the relative absorption of nimesulide from beta-cyclodextrin complex compared with that from conventional formulations of the drug makes the use of such fast-releasing complexes rather questionable. Only a limited number of assay procedures (HPLC, spectrophotometric, spectrofluorimetric) for the determination of nimesulide and its metabolite in plasma/urine samples or in dosage forms have been reported in the literature. The purpose of this review is to provide a concise overview of the pharmacological and pharmaceutical profile of nimesulide. Various investigations carried out recently are reported, although older references to research performed on nimesulide have also been included, where appropriate.

The impact of financing and quality changes on health care demand in Niger

This paper assesses the demand effects of a cost recovery and quality improvement pilot study conducted in Niger in 1993. Direct user charges and indirect insurance payments were implemented in government health care facilities in different parts of the country, and were preceded or accompanied by quality changes in these facilities. Decision-making by patients is modelled as a three-stage process of reporting an illness, seeking treatment and choice of provider; and multinomial nested logit techniques are used to estimate the parameters of the decision-tree. Overall, the results give a reasonably favourable impression of the policy changes. In neither case is there evidence of serious reductions in access or increases in cost. Particularly notable is that despite an increase in formal user charges, the observed decline in rates of visits is statistically insignificant, suggesting the success of measures to improve quality of health care in public facilities. The observed increase in the probability of formal visits in the district with indirect payments is also striking. Both contrast with the control region of Illela, where neither user charges were introduced nor were any efforts made to improve quality. The data suggest that higher utilization of formal care, probably due to improvements in quality, outweighed the decrease in utilization that may have come about due to introduction of cost recovery, so that the net effect of the policy changes was an increase in utilization. Quality considerations appear to be important in ensuring the long-term success of cost sharing.

Health reform for children: the Egyptian experience with school health insurance

In June 1992, the People's Assembly of Egypt passed Law 99 expanding health insurance to cover all school children. This was one of the most important initiatives undertaken in recent years by the Ministry of Health, and it effectively increased the number of beneficiaries covered by the Health Insurance Organization (HIO) from 3.75 million in 1988 to about 14 million in 1993. This paper first examines the policy processes for the introduction of this innovation in Egypt's health system. Next, the paper discusses the implementation and consequences of the new policy in terms of coverage, financing, benefits, and delivery of services, along with data on utilization and expenditures. Several important lessons derive from this analysis. First, major reform efforts are possible when there is a strong political commitment and the proposed program and solutions are acceptable to the key stakeholders. Second, compromises and trade-offs are essential to construct a politically feasible and ethically acceptable reform initiative. Third, while these trade-offs might yield short-term gains, the trade-offs in the long term may undermine the reform's capacity to achieve the anticipated equity enhancements and can potentially undermine the financial sustainability of the reform.

Enrolment procedures and self-selection by patients: evidence from a Polish family practice

This paper examines the consequences of patient enrollment procedures in a capitation-based family practice in Krakow (Poland), where the local city government used two different methods for preparation of patient lists. In the first, the city gave the individuals living within the practice area the option of withdrawing from being enrolled in the practice; in the second, individuals were given the option of enrolling in the practice. These two enrollment procedures, identified as 'active-negative' and 'active-positive' respectively, provide a natural experiment for investigating the effects of an enrollment methodology on the economics of a physician's practice. An examination of the data indicates that self-selecting enrollees utilize significantly greater quantities of health care compared to others, and university educated individuals and individuals more likely to fall ill are more likely to self-select into a practice. The study suggests that in order to reduce demand-side adverse selection, either the system of active-positive enrollment should be modified, or capitation rates should be risk-adjusted by health status rather than by demographic variables only. The policy implications of this study become even more significant as more and more physicians leave their salaried jobs to start state-financed independent practices.

Transposition-induced structural instability of Escherichia coli-mycobacteria shuttle vectors

Escherichia coli-mycobacteria shuttle vectors, derived from pAL5000 (a mycobacterial plasmid) and pUC19, were frequently found to undergo structural alterations due to transposition of IS1096, a Mycobacterium smegmatis transposable element, at a cluster of sites located within a small region of 60 bp, immediately upstream of a kanamycin resistance gene present in these vectors. The structural alterations led to deletion of large regions of the vector which, in several cases, were found to extend into the ORF2 (RepB) coding sequences of the pAL5000 replication region without affecting its replication capability. This suggests that the entire ORF2 coding sequences of the pAL5000 replication region may not be essential for replication of pAL5000-derived vectors. The deletion derivatives, which contain the minimal sequences required for replication and selection in mycobacteria, were found to be structurally stable and therefore these could be potentially used as stable vector systems for the transformation of mycobacteria.

Vascular gene therapy

Gene therapy is an exciting frontier in medicine today. Radiologists will be involved in tracking the effects of these new therapies through imaging. Vascular and interventional radiology techniques also are ideally suited for minimally invasive, readily monitored gene delivery. Gene therapy is accomplished through gene augmentation or gene blocking. The latter is accomplished through antisense oligonucleotides or transcription factor decoys. Vectors are agents that facilitate gene delivery and expression and can be viral or nonviral. The vascular wall is an ideal target for gene therapy because of its central role in many biologic processes and its ready accessibility. Recombinant genes can be delivered ex vivo and in vivo, with the latter approaches involving open surgical, percutaneous injection, and endovascular catheter-based methods. Perforated, hydrogel-coated, and double balloon catheters have been used with varying success. Optimal catheter systems for gene transfer will enable delivery of the vector to the precise anatomic location with transfection limited to the cells of interest and will minimize shedding of the vector to distal sites, systemic effects of the therapeutic agent, and morbidity from the delivery method. Radiologists must become familiar with the basic rationale, strategies, and mechanisms of gene therapy and involved in its clinical trials to ensure an active role in this field.

Financing health services in Poland: new evidence on private expenditures

This paper estimates total expenditure on health care in Poland in 1994 and provides new evidence on high levels of private spending on health care. The analysis shows that health care expenditures in Poland are higher than has usually been maintained, and are comparable with the prevailing levels in many other European countries. Private expenditure on health is a significant proportion of total expenditure on health, and in particular on financing outpatient care. Available evidence indicates that informal payments made by patients to physicians contribute as much as double of the physician's salary, and thus form an important source of earnings for physicians. This situation of high private expenditures on health care and informal payments to physicians is likely to be true of other transitional economies of Central and Eastern Europe as well. One policy implication that emerges is these transitional economies face a big challenge in managing existing resources, as opposed to finding new resources, in the health sector more effectively to meet the health care needs of their population. The paper highlights the need for better understanding of the current availability and distribution of resources in the health sector and their directions of flow, in both public and private sectors, and suggests using tools such as National Health Accounts to track and monitor changes in the financing of the health care system.

Comparison of the steady state pharmacokinetics of two formulations of cyclosporin in patients with atopic dermatitis

A comparison was made of the efficacy, tolerability, safety and steady state pharmacokinetics of Sandimmun and Neoral in 11 stable atopic dermatitis patients already on Sandimmun. The study was of an open, crossover design. At entry into the trial, patients were switched to Neoral for 28 days. Treatment was switched back to Sandimmun for Days 28 to 42. The morning dose was given fasting, the evening dose after a standard meal. All measures of eczema severity improved during the Neoral treatment period. Neoral was markedly better tolerated with fewer side-effects. Switching from Sandimmun to Neoral at the same dose resulted in less variable pharmacokinetic profiles in both fasted and fed states. There was an increase in bioavailability with better, less variable and faster absorption, with a slightly reduced tmax, a higher mean Cmax (+43%) and a higher mean AUC (+30%) in fasted, but not fed patients. Higher trough levels (Cmin) occurred throughout for Neoral. These differences between the two formulations were not associated with any changes in safety parameters. Overall, Neoral was equivalent or superior to Sandimmun in tolerability and efficacy when given on a 1:1 dose basis.

Fatigue of Cord-Rubber Composites

Fatigue failure mechanisms and their dependence on cyclic loading frequency were assessed in the case of a nylon fiber-reinforced elastomer matrix composite representing the actual carcass of bias aircraft tires. Under uniaxial tension, the angle-plied composite specimens were subjected to a considerably large interply shear strain before failure. The composite specimens exhibited infinite fatigue life when stress amplitude was below a threshold level, i.e., fatigue endurance limit. Under cyclic stresses exceeding the endurance limit, localized damage in the form of fiber-matrix debonding and matrix cracking was formed and developed into the delamination eventually leading to gross failure of the composite. The process of damage accumulation was accompanied by a continuous increase of cyclic strain as well as temperature. Fatigue lifetime and the resistance to damage accumulation of aircraft tire carcass composite were strongly influenced by cyclic frequency. The use of higher frequency resulted in shorter fatigue lifetimes at a given stress amplitude and lower endurance limit. The extent of xdynamic creep at gross failure, which is defined as the increase of cyclic strain beyond initial elastic deformation, was roughly independent of stress amplitude under the frequency of 1 Hz, but decreased with higher stress amplitude when the frequency was raised to 10 Hz. Obviously a critical level of dynamic creep exists for gross failure of the composite and this level appears to be independent of the stress amplitude at low frequency. When the frequency is sufficiently high, heat generation due to hysteretic loss is expected to degrade the materials. In this situation, the critical level of dynamic creep for gross failure seems to be reduced by the loss of matrix flexibility as well as fiber-matrix bonding strength, with the degree of reduction becoming greater under higher stress amplitude.

Polycythaemia, delirium and mania

The case is described of a 65-year-old woman who initially presented with delirium caused by polycythaemia rubra vera. Following venesection she was discharged home recovered, but presented again shortly after with an episode of mania associated with relapse of her polycythaemia.