Valsartan Loaded Solid Lipid Nanoparticles: Development, Characterization, and In vitro and Ex vivo Evaluation

Qualitative analysis of a mucoadhesive polymeric (hydroxypropyl methylcellulose, HPMC) suspension of norfloxacin was carried out with the aim of developing an oral controlled release gastro-retentive dosage form. The characterization of ultrasonicated formulation was performed by Fourier Transform Infrared Spectroscopy (FTIR), Raman spectroscopy, X-ray powder diffraction (XRD) and Scanning electron microscopy (SEM) analyses. For interpretation, FTIR (400-4000 cm-1 region) and Raman (140-2400 cm-1 region) spectra were used. XRD data of pure drug, polymer and the mucoadhesive polymeric suspension were obtained using a powder diffractometer, scanned from a Bragg’s angle (2θ) of 10˚ to 70˚. In addition, dispersion of particle was studied using SEM techniques. The results from FTIR and Raman spectroscopic analyses of the mucoadhesive suspension suggested that carboxylic groups of norfloxacin and hydroxyl groups of HPMC undergo chemical interaction leading to esterification and hydrogen bonding. The XRD data indicated the retention of crystalline nature of norfloxacin in the mucoadhesive suspension. Moreover, the SEM image analysis suggested that in the formulation, maximum particles exhibited network like structure to produce pseudoplastic flow. From our analysis, it may be concluded that it is feasible to prepare a homogeneous, uniformly dispersed, pharmaceutically stable controlled release norfloxacin suspension that has better bioavailability and penetration capacity.

Genome-wide association study identifies multiple novel loci associated with disease progression in subjects with mild cognitive impairment

Alzheimer's disease (AD) is the leading cause of dementia among the elderly population; however, knowledge about genetic risk factors involved in disease progression is limited. We conducted a genome-wide association study (GWAS) using clinical decline as measured by changes in the Clinical Dementia Rating-sum of boxes as a quantitative trait to test for single-nucleotide polymorphisms (SNPs) that were associated with the rate of progression in 822 Caucasian subjects of amnestic mild cognitive impairment (MCI). There was no significant association with disease progress for any of the recently identified disease susceptibility variants in CLU, CR1, PICALM, BIN1, EPHA1, MS4A6A, MS4A4E or CD33 following multiple testing correction. We did, however, identify multiple novel loci that reached genome-wide significance at the 0.01 level. These top variants (rs7840202 at chr8 in UBR5: P=4.27 × 10(-14); rs11637611 with a cluster of SNPs at chr15q23 close to the Tay-Sachs disease locus: P=1.07 × 10(-15); and rs12752888 at chr1: P=3.08 × 10(-11)) were also associated with a significant decline in cognition as well as the conversion of subjects with MCI to a diagnosis of AD. Taken together, these variants define approximately 16.6% of the MCI sub-population with a faster rate of decline independent of the other known disease risk factors. In addition to providing new insights into protein pathways that may be involved with the progress to AD in MCI subjects, these variants if further validated may enable the identification of a more homogeneous population of subjects at an earlier stage of disease for testing novel hypotheses and/or therapies in the clinical setting.

Effector T cells immune reactivity among patients with acute hepatitis E

Hepatitis E virus (HEV) is a leading cause of acute viral hepatitis in several developing countries. Information on cellular immune responses during acute hepatitis E is limited. We therefore studied peripheral blood mononuclear cells (PBMCs) from patients with acute hepatitis E and healthy adult subjects who lacked anti-HEV antibodies for enumeration of various T-cell subsets using flow cytometry and to assess HEV-specific T effector cell responses using interferon-gamma ELISPOT assays. The patients showed increased numbers of CD8(+) cells and CD4(+) CD8(+) cells compared with healthy controls. In addition, the proportion of PBMCs that produced interferon-gamma in response to recombinant HEV open reading frame (ORF) 2 and ORF 3 proteins were found to be higher in patients than in healthy controls. Using pools of 15-mer overlapping peptides corresponding to these recombinant proteins, the immunodominant regions in these proteins for interferon-gamma-producing cells were mapped to regions corresponding to amino acids 181-249 and 301-489 of HEV ORF2 protein. These data provide evidence for the activation of effector T cells during acute hepatitis E. These responses may play a role in viral clearance from the host in patients with HEV infection.

Viral RNA but no evidence of replication can be detected in the peripheral blood mononuclear cells of hepatitis E virus-infected patients

Hepatitis E virus (HEV) infection is an important cause of acute viral hepatitis in several developing countries but has recently been shown to cause chronic hepatitis in immunosuppressed persons. Other hepatotropic viruses that cause chronic infection have been shown to infect peripheral blood mononuclear cells (PBMCs) and to persist in those cells. We therefore decided to look for evidence of replication of HEV in PBMCs obtained from patients with acute hepatitis E, using strand-specific assays for positive and negative HEV RNA. Of the 44 patients with acute hepatitis E during an outbreak in India, including 27 with detectable IgM anti-HEV and 19 with detectable serum HEV RNA, 11 had detectable HEV RNA in their PBMCs. However, of the six PBMC specimens with strong HEV RNA signal, none had detectable negative-strand HEV RNA, a marker of viral replication. These findings indicate the presence of HEV RNA but the absence of its replication in PBMCs from patients with acute hepatitis E.

mTOR signaling pathway regulates the IL-12/IL-10 axis in Leishmania donovani infection

Leishmania-induced interleukin-12 (IL-12) expression is negatively regulated by the phosphatidylinositol 3-kinase (PI3K) and extracellular signal regulated kinase (ERK) 1/2 pathways in human monocyte derived macrophages (MDMs). To extend these studies, we examined the pathways downstream from PI3K in L. donovani-induced reciprocal regulation of IL-12/IL-10 axis in THP-1-derived macrophages. We show for the first time that in THP-1-derived macrophages and human monocytes, mTOR inhibition by rapamycin reversed L. donovani-induced IL-12 and IL-10 modulation. L. donovani-induced phosphorylation of P70S6K, a correlate of mTOR activity, in TLR-stimulated THP-1 derived macrophages. This increase in P70S6K phosphorylation was completely blocked by rapamycin (mTOR inhibitor) and partially by wortmannin (PI3K inhibitor). These observations suggest that a PI3K independent pathway is operative in the modulation of IL-12 and IL-10. Blocking of TLR2 significantly attenuated IL-10 induced by the parasite, but did not affect IL-12 production. Thus, our data suggests that intracellular network of PI3K and mTOR pathway control IL-12/IL-10 modulation by L. donovani. mTOR inhibitors may be attractive molecules to reverse this modulation and may result in control of disease.

mTOR signaling pathway regulates the IL-12/IL-10 axis in Leishmania donovani infection (158.17)

Macrophage stimulation with TLR ligands and concurrent infection with L. donovani promastigotes results in decreased IL-12 and increased IL-10 production compared to stimulation with TLR agonists. Because mTOR deficiency has been associated with increased IL-12, we hypothesized that host mTOR is central to the evasive effect of parasite on TLR-induced IL-12 inhibition. Here we demonstrate that L. donovani activate mTOR via phosphoinositide 3-kinase/Akt. Parasite enhanced phosphorylation of P70S6K (a correlate of mTOR activity), was completely blocked by rapamycin (mTOR inhibitor). This inhibition resulted in reversal of IL-12, IL-10 production and iNOS expression modulated by the parasite. These observations suggest that mTOR dependent pathway is operative in the modulation of IL-12/IL-10 cytokine axis by the parasite. Parasite internalization by macrophages was not affected by rapamycin treatment, suggesting cytokine reversal mediated by rapamycin is independent of parasite entry. Further blocking TLR2 resulted in the reversal of leishmania-induced IL-10 production. Collectively, these findings provide new insight into the mechanism controlling modulation of IL-12 & IL-10 cytokines by leishmania involving the intracellular network of mTOR pathway in a TLR2-dependent manner. mTOR inhibitors may be an attractive molecule to reverse cytokine modulation and control the infection.

A British Society of Paediatric Gastroenterology, Hepatology and Nutrition survey of the effectiveness and safety of adalimumab in children with inflammatory bowel disease

BACKGROUND

Adalimumab is efficacious therapy for adults with Crohn's disease (CD).

AIM

To summarise the United Kingdom and Republic of Ireland paediatric adalimumab experience.

METHODS

British Society of Paediatric Gastroenterology, Hepatology and Nutrition (BSPGHAN) members with Inflammatory Bowel Disease (IBD) patients <18 years old commencing adalimumab with at least 4 weeks follow-up. Patient demographics and details of treatment were then collected. Response and remission was assessed using the Paediatric Crohn's Disease Activity Index (PCDAI)/Physicians Global Assessment (PGA).

RESULTS

Seventy-two patients [70 CD, 1 ulcerative colitis (UC), 1 IBD unclassified (IBDU)] from 19 paediatric-centres received adalimumab at a median age of 14.8 (IQR 3.1, range 6.1-17.8) years; 66/70 CD (94%) had previously received infliximab. A dose of 80 mg then 40 mg was used for induction in 41(59%) and 40 mg fortnightly for maintenance in 61 (90%). Remission rates were 24%, 58% and 41% at 1, 6 and 12 months, respectively. Overall 43 (61%) went into remission at some point, with 24 (35%) requiring escalation of therapy. Remission rates were higher in those on concomitant immunosuppression cf. those not on immunosuppression [34/46 (74%) vs. 9/24 (37%), respectively, (χ(2) 8.8, P=0.003)]. There were 15 adverse events (21%) including four (6%) serious adverse events with two sepsis related deaths in patients who were also on immunosuppression and home parenteral nutrition (3% mortality rate).

CONCLUSIONS

Adalimumab is useful in treatment of refractory paediatric patients with a remission rate of 61%. This treatment benefit should be balanced against side effects, including in this study a 3% mortality rate.

Adaptive immune responses during acute uncomplicated and fulminant hepatitis E

BACKGROUND AND AIM

Hepatitis E virus (HEV) infection is endemic in several developing countries. Clinical manifestations of this infection vary widely from asymptomatic infection to uncomplicated acute viral hepatitis and fulminant hepatic failure. The pathogenesis of this disease and the reason of varying disease severity remain unknown. In viral infections, tissue injury can be caused either by virus itself or by host immune responses directed against infected cells. We therefore studied adaptive immune responses to HEV antigens in patients with hepatitis E of varying disease severity and healthy controls.

METHODS

Cytokine secreting CD4+ T cells and antibody-producing B cells specific for HEV were enumerated through intracellular cytokine staining and enzyme-linked immunosorbent spot assay, respectively.

RESULTS

Patients with fulminant hepatitis E had a less marked expansion of HEV-specific interferon-γ or tumor necrosis factor-a secreting CD4+ T cells than patients with uncomplicated hepatitis E and healthy controls. These patients also had fewer CD4+ T cells that produce γ-interferon or tumor necrosis factor-a upon in vitro polyclonal stimulation. In addition, patients with fulminant disease had a more marked expansion of B cells that can secrete immunoglobulin G anti-HEV than patients with uncomplicated infection and control patients.

CONCLUSION

These findings suggest that less-marked antiviral cellular immune responses and heightened antiviral humoral responses are associated with a more severe disease during HEV infection.

Evidence of hepatitis E virus exposure among seronegative healthy residents of an endemic area

OBJECTIVE

Hepatitis E virus (HEV) infection is endemic in the Indian subcontinent. Detection of serum anti-HEV IgG has traditionally been used to determine prior exposure to this virus. We studied HEV-specific recall immune responses in healthy subjects with and without detectable anti-HEV IgG.

METHODS

Memory B and T cells specific for HEV recombinant proteins pORF2 and pORF3 were estimated among healthy subjects residing in an HEV-endemic region using enzyme-linked immunospot (ELISPOT) assays.

RESULTS

Anti-HEV IgG-negative and anti-HEV IgG-positive healthy subjects had a similar median (range) number of IgG-secreting memory B cells specific for HEV pORF2 [percent of total IgG-producing cells: 0.39 (0-13.63) vs. 0.83 (0-12.78)] and HEV pORF3 [0.33 (0.05-12.35) vs. 1.01 (0.08-9.48)], and of IFN-γ-secreting memory T cells specific for HEV pORF2 [per one million PBMCs: 16 (0-220) vs. 36.5 (0-474)] and HEV pORF3 [166 (0-957) vs. 70.5 (0-533)]. Eight healthy volunteers residing in the USA and studied as controls lacked detectable T cells specific for HEV pORF2.

CONCLUSION

ELISPOT assays may detect evidence of prior HEV infection in persons residing in areas endemic for this infection and lacking detectable anti-HEV IgG. Seroepidemiological studies that use the serum anti-HEV IgG test may underestimate the frequency of exposure to HEV.

Genetic contribution and associated pathophysiology in end-stage renal disease

End-stage renal disease (ESRD) or chronic kidney disease (CKD) is the terminal state of the kidney when its function has been permanently and irreversibly damaged. A wide variety of etiologies and pathological processes culminate in ESRD, and both environmental and genetic factors contribute to its development and progression. Various reports suggest that susceptibility to develop ESRD has a significant genetic component. These studies include familial aggregation studies, comparisons of incidence rates between different racial or ethnic populations, and segregation analysis. Genetic approaches have been used to identify genes that contribute to genetic susceptibility. Many studies have now been carried out assessing the contribution of specific “candidate genes”, which correlate with different functions that are involved in the renal pathogenesis. Independent studies for specific associated genes have frequently provided contradictory results. This may be due, in part, to the modest contribution to genetic susceptibility which these genes impart. With the availability of different genomewide association studies, chromosomal regions harboring novel, previously unrecognized, genes that may contribute to renal diseases have been recently reported. We have focused on different genetic studies conducted on ESRD and have discussed the strength and weaknesses of these studies. The nonmuscle myosin heavy chain 9 gene (MYH9) and renin–angiotensin system (RAS) have been discussed in detail.

Oral calcium supplementation reverses the biochemical pattern of parathyroid hormone resistance in underprivileged Indian toddlers

BACKGROUND

Toddlers in Pune, India, accustomed to low dietary calcium intake but vitamin D replete have low serum ionised calcium and inappropriately raised serum inorganic phosphorus concentrations together with elevated serum parathyroid hormone (PTH) concentrations. We hypothesised that dietary calcium deficiency leads to end organ resistance to PTH, thus resulting in mild hypocalcaemia and hyperphosphataemia, and that this would be reversed by oral calcium supplementation.

METHODS

51 subjects (25 male; mean (SD) age 2.4 (0.8) years) from an urban slum in Pune were randomised to 500 mg of oral calcium supplement or placebo, daily, for 8 weeks. All subjects received 20 mg of oral elemental iron, daily, as 90% had a serum ferritin concentration <12 microg/l. All subjects were examined for clinical stigmata of rickets and had a wrist radiograph performed. Serum concentrations of ionised calcium, phosphorus, PTH and fibroblast growth factor-23 (FGF-23) were measured at the start and end of the trial.

RESULTS

No subject had clinical or radiological evidence of rickets. There was a significant increase in mean serum ionised calcium concentration (p<0.001) in the supplemented but not the placebo group (p = 0.32). The decrease in mean serum phosphorus concentration in the supplemented group was greater (p<0.001) than in the placebo group (p = 0.003). Mean serum PTH fell in the calcium supplemented (p = 0.001) but not in the placebo (p = 0.303) group. The mean serum FGF-23 concentration did not change in response to calcium supplementation.

CONCLUSIONS

From these data the authors conclude that low dietary calcium intake is associated with resistance to PTH.

Increased T-lymphocyte apoptosis in lupus correlates with disease activity and may be responsible for reduced T-cell frequency: a cross-sectional and longitudinal study

Apoptosis of lymphocytes is increased in patients with lupus. This may be pathogenic leading to increased load of autoantigens or may be a bystander effect of immune activation. A major unresolved issue is whether apoptosis is related to disease activity. Also its association with lymphocyte frequencies, anti-nucleosomal antibodies and serum IL 10 levels needs to be explored further. The aims of this study are to measure T- and B-lymphocyte apoptosis in patients with lupus and look at the effect of disease activity in a cross-sectional and longitudinal design and to determine frequency of T and B cells, level of anti-nucleosomal antibodies and serum IL 10 and assess their relationship with apoptosis. This study included 41 patients with SLE and 20 controls. A cutoff value of 4 in systemic lupus erythematosus disease activity index (SLEDAI) was used to separate active from inactive SLE. The frequency and degree of apoptosis of T and B lymphocyte were enumerated by flow cytometry using peripheral blood mononuclear cells (PBMCs) stained with CD3/CD19 and annexin V/PI. The data for T/B cell frequency are represented as % of these cells in the PBMC population, whereas percentage of apoptotic cells is out of total T or B cells. Serum anti-nucleosomal antibodies and IL 10 were assayed using ELISA. A repeat assessment of these parameters was carried out in 11 active patients when they became inactive. We found higher T-lymphocyte apoptosis in patients with SLE versus controls (14.8 +/- 9.2, 7.2 +/- 3.0; P < 0.05) and a lower frequency of T cells (72.7 +/- 12.6, 79.9 +/- 5.8; P < 0.05). T-lymphocyte apoptosis was higher in patients with active disease compared with inactive (18.5 +/- 11.3, 11.6 +/- 5.4; P = 0.05). Further, T-lymphocyte apoptosis directly correlated with SLEDAI (r = 0.37, P < 0.05) and inversely with T-cell frequency (r = -0.29, P < 0.05). Anti-nucleosomal antibodies correlated with SLEDAI but not apoptosis. On longitudinal follow-up, a decline in T-cell apoptosis was seen in patients with SLE, however this was not statistically significant. We confirmed a higher degree of apoptosis in T-lymphocytes in patients with SLE and found a direct correlation of T-cell apoptosis with disease activity. Patients had reduced T-cell frequency, which inversely correlated with T-cell apoptosis and may suggest a cause-effect relationship.

Epidemiology of hepatitis E: current status

Hepatitis E, caused by infection with hepatitis E virus (HEV), is a common cause of acute hepatitis in areas with poor sanitation. The virus has four genotypes with one serotype: genotypes 1 and 2 exclusively infect humans, whereas genotypes 3 and 4 also infect other animals, particularly pigs. In endemic areas, both large outbreaks of acute hepatitis as well as sporadic cases occur frequently. These cases are usually due to genotype 1 or 2 HEV and are predominantly caused by fecal-oral transmission, usually through contamination of drinking water; contaminated food, materno-fetal (vertical spread) and parenteral routes are less common modes of infection. The acute hepatitis caused by this virus has the highest attack rates in young adults and the disease is particularly severe among pregnant women. HEV superinfection can occur among persons with pre-existing chronic liver disease. In non-endemic regions, locally acquired disease was believed to be extremely uncommon. However, in recent years, an increasing number of cases, due mostly due to genotype 3 or 4 HEV, have been recognized. These are more often elderly men who have other coexisting illnesses, and appear to be related to zoonotic transmission from pigs, wild boars and deer, either food-borne or otherwise. Also, chronic infection with genotype 3 HEV has been reported among immunosuppressed persons in these regions. A subunit vaccine has been shown to be effective in preventing clinical disease, but is not yet commercially available. Our understanding of hepatitis E epidemiology has undergone major changes in recent years, and the future may hold even more surprises.

Q-switched Nd:YAG Laser to Treat Nevomelanocytic Nevi

Background:

Q-switched Nd:YAG laser, a melanin pigment-specific laser was used to treat melanocytic nevi in Indian patients.

Objective:

To assess the clinical response of nevi to Q-switched Nd:YAG laser of 1064 nm wavelength.

Materials and Methods:

Nineteen patients received an average of 2.57 treatments with Q-switched Nd:YAG laser of 1064 nm wavelength, repetition rate of 10 Hz, 10 nanoseconds pulse width, and spot size of 4 mm to 6 mm with a fluence ranging from 4 to 9.7 joules/cm². The clinical end point of the laser treatment was brisk whitening. The response was assessed by using a global assessment score.

Results:

The clinical global assessment score showed excellent response in 8/19 patients and good response in 6/19 patients.

Conclusion:

The Q-switched Nd:YAG laser of 1064 nm wavelength resulted in significant improvement (lightening) of nevi.

Severe tissue trauma triggers the autoimmune state systemic lupus erythematosus in the MRL/++ lupus-prone mouse

Tissue damage associated with a severe injury can result in profound inflammatory responses that may trigger autoimmune development in lupus-prone individuals. In this study, we investigated the role of a large full-thickness cutaneous burn injury on the early onset of autoimmune disease in lupus-prone MRL/++ mice. MRL/++ mice (chronic model) exhibit autoimmune symptoms at >70 weeks of age, whereas MRL/-Faslpr mice (acute model) develop autoimmune disease in 17–22 weeks due to a lymphoproliferative mutation. Autoimmune disease developed in MRL/++ mice (4–15 weeks post injury) is manifested by skin lesions, vasculitis, epidermal ulcers, cellular infiltration, splenomegaly, lymphadenopathy, hypergammaglobulinemia, elevated autoantibodies and renal pathologies including proteinuria, glomerulonephritis and immune complex deposition; complications that contribute to reduced survival. Transcription studies of wound margin tissue show a correlation between the pathogenic effects of dysregulated IL-1β, IL-6, TNF-α and PGE2 synthesis during early wound healing and early onset of autoimmune disease. Interestingly, MRL/++ mice with healed wounds (30–40 days post burn) strongly rejected skin isografts. Conversely, skin isografts transplanted onto naive age-matched MRL/++ littermates achieved long-term survival. Collectively, these findings suggest that traumatic injury exacerbates inflammatory skin disease and severe multi-organ pathogenesis in lupus-prone mice.