Light Sensitive Liposomes: A Novel Strategy for Targeted Drug Delivery

Light-sensitive liposomes have emerged as a promising platform for drug delivery, offering the potential for precise control over drug release and targeted therapy. These lipid-based nanoparticles possess photoresponsive properties, allowing them to undergo structural changes or release therapeutic payloads upon exposure to specific wavelengths of light. This review presents an overview of the design principles, fabrication methods, and applications of light-sensitive liposomes in drug delivery. Further, this article also discusses the incorporation of light-sensitive moieties, such as azobenzene, spiropyran, and diarylethene, into liposomal structures, enabling spatiotemporal control over drug release. The utilization of photosensitizers and imaging agents to enhance the functionality and versatility of light-sensitive liposomes is also highlighted. Finally, the recent advances, challenges, and future directions in the field, emphasizing the potential for these innovative nanocarriers to revolutionize targeted therapeutics, are also discussed.

Dynamical independence: Discovering emergent macroscopic processes in complex dynamical systems

We introduce a notion of emergence for macroscopic variables associated with highly multivariate microscopic dynamical processes. Dynamical independence instantiates the intuition of an emergent macroscopic process as one possessing the characteristics of a dynamical system "in its own right," with its own dynamical laws distinct from those of the underlying microscopic dynamics. We quantify (departure from) dynamical independence by a transformation-invariant Shannon information-based measure of dynamical dependence. We emphasize the data-driven discovery of dynamically independent macroscopic variables, and introduce the idea of a multiscale "emergence portrait" for complex systems. We show how dynamical dependence may be computed explicitly for linear systems in both time and frequency domains, facilitating discovery of emergent phenomena across spatiotemporal scales, and outline application of the linear operationalization to inference of emergence portraits for neural systems from neurophysiological time-series data. We discuss dynamical independence for discrete- and continuous-time deterministic dynamics, with potential application to Hamiltonian mechanics and classical complex systems such as flocking and cellular automata.

Trait phenomenological control predicts experience of mirror synaesthesia and the rubber hand illusion

In hypnotic responding, expectancies arising from imaginative suggestion drive striking experiential changes (e.g., hallucinations) - which are experienced as involuntary - according to a normally distributed and stable trait ability (hypnotisability). Such experiences can be triggered by implicit suggestion and occur outside the hypnotic context. In large sample studies (of 156, 404 and 353 participants), we report substantial relationships between hypnotisability and experimental measures of experiential change in mirror-sensory synaesthesia and the rubber hand illusion comparable to relationships between hypnotisability and individual hypnosis scale items. The control of phenomenology to meet expectancies arising from perceived task requirements can account for experiential change in psychological experiments.

Conscious perception and the modulatory role of dopamine: no effect of the dopamine D2 agonist cabergoline on visual masking, the attentional blink, and probabilistic discrimination

RATIONALE

Conscious perception is thought to depend on global amplification of sensory input. In recent years, striatal dopamine has been proposed to be involved in gating information and conscious access, due to its modulatory influence on thalamocortical connectivity.

OBJECTIVES

Since much of the evidence that implicates striatal dopamine is correlational, we conducted a double-blind crossover pharmacological study in which we administered cabergoline-a dopamine D2 agonist-and placebo to 30 healthy participants. Under both conditions, we subjected participants to several well-established experimental conscious-perception paradigms, such as backward masking and the attentional blink task.

RESULTS

We found no evidence in support of an effect of cabergoline on conscious perception: key behavioral and event-related potential (ERP) findings associated with each of these tasks were unaffected by cabergoline.

CONCLUSIONS

Our results cast doubt on a causal role for dopamine in visual perception. It remains an open possibility that dopamine has causal effects in other tasks, perhaps where perceptual uncertainty is more prominent.

Abstract 3554: miR-139 is associated with improved prognosis in patients with localized prostate cancer

Background: We previously identified a panel of five miRNAs associated with biochemical recurrence and metastasis following prostatectomy based on NGS-based whole miRNome discovery and qPCR-based validation analysis. In this analysis, we examine the effect of miR-139-5p, one of the down-regulated miRNAs identified in the panel, in greater detail.

Methods: Using a cohort of 585 patients treated with radical prostatectomy, we examined the prognostic significance of miR-139 (dichotomized around the median) using the Kaplan Meier method and Cox proportional hazard models. We validated these results using The Cancer Genome Atlas (TCGA) data. We created cell lines that over-expressed miR-139 or transiently transfected cells using miR-139 mimics for functional assays. Finally, we examined pathways through which miR-139 may function using prediction algorithms and confirmed targets by Western blotting and reporter assays.

Results: MiR-139 down-regulation was significantly associated with a variety of accepted prognostic factors in prostate cancer, including Gleason score, pathologic stage, margin positivity and lymph node status. MiR-139 was associated with prognosis: the cumulative incidence of biochemical recurrence and metastasis were significantly lower among patients with high miR-139 expression (p=0.0004 and 0.038, respectively). After adjusting for known prognostic factors, patients with high miR-139 expression had significantly lower risk of recurrence (HR 0.77, 95% 0.58-1.04). Validation in the TCGA dataset showed a significant association between dichotomized miR-139 expression and biochemical recurrence (OR 0.52, 95% CI 0.33-0.82). Over-expression of miR-139 in prostate cancer cells led to a significant reduction in cell proliferation and migration compared to control cells, with cells arrested in G2 of cell cycle. IGF1R, RUNX1 and AXL were identified as potential gene targets of miR-139 based on their association with prostate cancer growth pathways and multiple miRNA binding site prediction tools. The reporter assays using luciferase gene constructs containing the predicted miRNA targeting sequence from IGFR1 and RUNX1 verified them as direct targets of miR-139. Furthermore, Western blotting of prostate cancer cells demonstrated RUNX1 and AXL expression were inhibited by miR-139 treatment, which was reversed by addition of miR-139 antagomir. Examination of the molecular mechanism of growth inhibition by miR-139 revealed the downregulation of activated Akt and cyclin D1, with upregulation of the CDK inhibitor p21.

Conclusions: miR-139 is associated with improved prognosis in patients with localized prostate cancer, which may be mediated through inhibition of IGF1R, RUNX1 and/or AXL and their associated growth signaling pathways.

Citation Format: Tania Benatar, Robert K. Nam, Elizabeth Kobylecky, Yutaka Amemiya, Arun K. Seth. miR-139 is associated with improved prognosis in patients with localized prostate cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2019; 2019 Mar 29-Apr 3; Atlanta, GA. Philadelphia (PA): AACR; Cancer Res 2019;79(13 Suppl):Abstract nr 3554.

Abstract A079: MicroRNA-139 regulates prostate cancer aggressiveness by targeting IGF1R

Background: Dysregulated microRNA (miRNA) expression has been implicated in prostate cancer progression. We previously identified a panel of five miRNAs associated with biochemical recurrence and metastasis following prostatectomy based on NGS-based whole miRNome discovery and qPCR-based validation analysis. In this analysis, we examine the effect of miR-139-5p, one of the downregulated miRNAs identified in the panel, in greater detail.

Methods: Using a cohort of 585 patients treated with radical prostatectomy, we examined the prognostic significance of miR-139 (dichotomized around the median) using the Kaplan Meier method and Cox proportional hazard models. We validated these results using The Cancer Genome Atlas (TCGA) data. We created cell lines that overexpressed miR-139 for functional assays. Finally, we examined pathways through which miR-139 may function using prediction algorithms and confirmed targets by Western blotting and reporter assays.

Results: MiR-139 downregulation was significantly associated with a variety of accepted prognostic factors in prostate cancer, including Gleason score, pathologic stage, margin positivity, and lymph node status. MiR-139 was associated with prognosis: the cumulative incidence of biochemical recurrence and metastasis was significantly lower among patients with high miR-139 expression (p=0.0004 and 0.038, respectively). After adjusting for known prognostic factors, patients with high miR-139 expression had significantly lower risk of recurrence (HR 0.77, 95% 0.58-1.04). Validation in the TCGA dataset showed a significant association between dichotomized miR-139 expression and biochemical recurrence (OR 0.52, 95% CI 0.33-0.82). Overexpression of miR-139 in PC3 and DU145 prostate cancer cells led to a significant reduction in cell proliferation and migration compared to control cells. IGF1R was identified as a potential target of miR-139 based on previous work in colorectal and non-small cell lung cancers. Reduced luciferase reporter activity was observed upon co-transfection of the 3′ UTR of IGF1Rβ with miR-139 mimic compared to co-transfection with control mimic. Furthermore, Western blotting of PC3 cells overexpressing miR-139 revealed reduced IGF1Rβ protein expression, as well as reduced expression of its downstream pathway proteins pAKT and pERK. Cell cycle analysis indicated a significantly increased number of cells arrested in G2/M phase in PC3 cells overexpressing miR-139. This was accompanied by an increase in β-galactosidase stained senescent cells and p21 protein expression.

Conclusions: miR-139 is associated with improved prognosis in patients with localized prostate cancer. This appears to be mediated through an IGF1R pathway leading to increased p21 expression, resulting in prostate cancer cell senescence from G2 arrest.

Citation Format: Yutaka Amemiya, Christopher J. Wallis, Tania Benatar, Elizabeth Kobylecky, Linda Sugar, Christopher Sherman, Robert Nam, Arun K. Seth. MicroRNA-139 regulates prostate cancer aggressiveness by targeting IGF1R [abstract]. In: Proceedings of the AACR Special Conference: Prostate Cancer: Advances in Basic, Translational, and Clinical Research; 2017 Dec 2-5; Orlando, Florida. Philadelphia (PA): AACR; Cancer Res 2018;78(16 Suppl):Abstract nr A079.

Effect of coenzyme Q10 alone and its combination with metformin on streptozotocin-nicotinamide-induced diabetic nephropathy in rats

Objectives:

This study was aimed to investigate the therapeutic potential of coenzyme Q10 and its combination with metformin on streptozotocin (STZ)-nicotinamide-induced diabetic nephropathy (DN).

Materials and Methods:

Type 2 diabetes in rats was induced with STZ-nicotinamide. The diabetic rats were treated with coenzyme Q10 (10 mg/kg, p.o.) alone or coenzyme Q10 + metformin. Various parameters of renal function tests such as serum creatinine, urea, uric acid, and markers of oxidative stress such as renal malondialdehyde (MDA) level, superoxide dismutase (SOD), and catalase (CAT) activities were measured. Tumor necrosis factor-α (TNF-α), myeloperoxidase (MPO) activity, transforming growth factor-β (TGF-β), and nitrite content were estimated in renal tissues. All treated animal were subjected to histopathological changes of kidney.

Result:

Diabetic rats showed a significant reduction in renal function, which was reflected with an increase in serum urea, serum creatinine, uric acid. In addition, STZ-nicotinamide caused renal tubular damage with a higher MDA level, depletion of SOD and CAT activity and glutathione (GSH) level. Moreover, TNF-α, MPO activity, TGF-β, and nitrite content were significantly increased in diabetic rats, while treatment with coenzyme Q10 or metformin or their combination ameliorate STZ-nicotinamide induced renal damage due to improvement in renal function, oxidative stress, suppression of TNF-α, MPO activity, TGF-β and nitrite content along with histopathological changes.

Conclusions:

This finding suggests that the treatment with coenzyme Q10 or metformin showed significant renoprotective effect against STZ-nicotinamide-induced DN. However, concomitant administration of both showed a better renoprotective effect than coenzyme Q10 or metformin alone treatment.

Abstract C68: Global transcriptome sequencing of ethnically diverse formalin-fixed patient samples identifies biomarkers of recurrence in prostate cancer

Prostate cancer remains the second leading cause of cancer death in American men, but biomarkers that can predict outcome following treatment are urgently needed to identify patients with aggressive disease. In an effort to identify biomarkers of recurrence, we have performed global RNA-sequencing on 106 formalin-fixed, paraffin-embedded (FFPE) prostatectomy samples from 100 patients at three independent sites, and identified a new set of biomarkers of biochemical recurrence composed of a 24-gene panel including 22 protein-coding genes and two non-coding genes. We observed excellent correlation between TaqMan and RNAseq values, as well as for RNAseq between replicate libraries. We validated this 24-gene panel on an independent publicly available dataset of 140 patients and this new panel outperformed previously published markers based on cell proliferation gene sets. In addition, we have identified genes that are differentially expressed between African-American and Caucasian prostate cancer patients, and mitochondrial SNPs that are associated with both race and outcome. We observed a number of genes relevant to prostate cancer biology including ETV5, ZEB1, ZEB2, B2M, FYN, and miR-183 that were differentially expressed between African-American and Caucasian patients. These genes may play a role in the disparities observed in African-American patients who have significantly worse outcomes relative to Caucasian patients with prostate cancer.

Citation Format: Jianpeng Xu, Qi Long, Adeboye O. Osunkoya, Soma Sannigrahi, Brent A. Johnson, Wei Zhou, Theresa Gillespie, Jong Y. Park, Robert K. Nam, Linda Sugar, Aleksandra Stanimirovic, Arun K. Seth, John A. Petros, Carlos S. Moreno. Global transcriptome sequencing of ethnically diverse formalin-fixed patient samples identifies biomarkers of recurrence in prostate cancer. [abstract]. In: Proceedings of the Sixth AACR Conference: The Science of Cancer Health Disparities; Dec 6–9, 2013; Atlanta, GA. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2014;23(11 Suppl):Abstract nr C68. doi:10.1158/1538-7755.DISP13-C68

Global transcriptome analysis of formalin-fixed prostate cancer specimens identifies biomarkers of disease recurrence

Prostate cancer remains the second leading cause of cancer death in American men and there is an unmet need for biomarkers to identify patients with aggressive disease. In an effort to identify biomarkers of recurrence, we performed global RNA sequencing on 106 formalin-fixed, paraffin-embedded prostatectomy samples from 100 patients at three independent sites, defining a 24-gene signature panel. The 24 genes in this panel function in cell-cycle progression, angiogenesis, hypoxia, apoptosis, PI3K signaling, steroid metabolism, translation, chromatin modification, and transcription. Sixteen genes have been associated with cancer, with five specifically associated with prostate cancer (BTG2, IGFBP3, SIRT1, MXI1, and FDPS). Validation was performed on an independent publicly available dataset of 140 patients, where the new signature panel outperformed markers published previously in terms of predicting biochemical recurrence. Our work also identified differences in gene expression between Gleason pattern 4 + 3 and 3 + 4 tumors, including several genes involved in the epithelial-to-mesenchymal transition and developmental pathways. Overall, this study defines a novel biomarker panel that has the potential to improve the clinical management of prostate cancer.

Modes and models in disorders of consciousness science

The clinical assessment of non-communicative brain damaged patients is extremely difficult and there is a need for paraclinical diagnostic markers of the level of consciousness. In the last few years, progress within neuroimaging has led to a growing body of studies investigating vegetative state and minimally conscious state patients, which can be classified in two main approaches. Active neuroimaging paradigms search for a response to command without requiring a motor response. Passive neuroimaging paradigms investigate spontaneous brain activity and brain responses to external stimuli and aim at identifying neural correlates of consciousness. Other passive paradigms eschew neuroimaging in favour of behavioural markers which reliably distinguish conscious and unconscious conditions in healthy controls. In order to furnish accurate diagnostic criteria, a mechanistic explanation of how the brain gives rise to consciousness seems desirable. Mechanistic and theoretical approaches could also ultimately lead to a unification of passive and active paradigms in a coherent diagnostic approach. In this paper, we survey current passive and active paradigms available for diagnosis of residual consciousness in vegetative state and minimally conscious patients. We then review the current main theories of consciousness and see how they can apply in this context. Finally, we discuss some avenues for future research in this domain.

A study on knowledge, beliefs and attitude towards leprosy in students of Jaipur, Rajasthan

The objective of this study was to determine the knowledge, beliefs and attitudes regarding leprosy in school students of Jaipur district. A cross-sectional study was conducted from August 2010 to February 2011 on 1199 students (rural and urban) studying in class 10th and above. The findings of this study showed fair knowledge in students about cause, signs and symptoms of leprosy but less knowledge about prevention and treatment of the disease. Myths and beliefs were more prevalent in rural students as compared to urban ones. Both the groups showed positive attitude toward leprosy with 30-50% students showing neutral approach but negative reaction was more in rural students. In conclusion the study highlights to emphasize on health education in students and improving knowledge to develop positive attitude towards leprosy.

Effects of partner proteins on BCA2 RING ligase activity

Background

BCA2 is an E3 ligase linked with hormone responsive breast cancers. We have demonstrated previously that the RING E3 ligase BCA2 has autoubiquitination activity and is a very unstable protein. Previously, only Rab7, tetherin, ubiquitin and UBC9 were known to directly interact with BCA2.

Methods

Here, additional BCA2 binding proteins were found using yeast two-hybrid and bacterial-II-hybrid screening techniques with Human breast and HeLa cDNA libraries. Co-expression of these proteins was analyzed through IHC of TMAs. Investigation of the molecular interactions and effects were examined through a series of in vivo and in vitro assays.

Results

Ten unique BCA2 interacting proteins were identified, two of which were hHR23a and 14-3-3sigma. Both hHR23a and 14-3-3sigma are co-expressed with BCA2 in breast cancer cell lines and patient breast tumors (n = 105). hHR23a and BCA2 expression was significantly correlated (P = < 0.0001 and P = 0.0113) in both nucleus and cytoplasm. BCA2 expression showed a statistically significant correlation with tumor grade. High cytoplasmic hHR23a trended towards negative nodal status. Binding to BCA2 by hHR23a and 14-3-3sigma was confirmed in vitro using tagged partner proteins and BCA2. hHR23a and 14-3-3sigma effect the autoubiquitination and auto-degradation activity of BCA2. Ubiquitination of hHR23a-bound BCA2 was found to be dramatically lower than that of free BCA2, suggesting that hHR23a promotes the stabilization of BCA2 by inactivating its autoubiquitination activity, without degradation of hHR23a. On the other hand, phosphorylated BCA2 protein is stabilized by interaction with 14-3-3sigma both with and without proteasome inhibitor MG-132 suggesting that BCA2 is regulated by multiple degradation pathways.

Conclusions

The interaction between BCA2 and hHR23a in breast cancer cells stabilizes BCA2. High expression of BCA2 is correlated with grade in breast cancer, suggesting regulation of this E3 ligase is important to cancer progression.

The Enactive Torch: A New Tool for the Science of Perception

The cognitive sciences are increasingly coming to terms with the embodied, embedded, extended, and experiential aspects of the mind. Exemplifying this shift, the enactive approach points to an essential role of goal-directed bodily activity in the generation of meaningful perceptual experience, i.e., sense-making. Here, building on recent insights into the transformative effects of practical tool-use, we make use of the enactive approach in order to provide a definition of an enactive interface in terms of augmented sense-making. We introduce such a custom-built interface, the Enactive Torch, and present a study of its experiential effects. The results demonstrate that the user experience is not adequately captured by any standardly assumed perceptual modality; rather, it is a new feeling that is mediated by the design of the device and shaped by the overall situation of the task. Taken together these findings show that there is much to be gained by synergies between engineering and the cognitive sciences in the creation of new experience-centered technology. We suggest that the guiding principle should be the design of interfaces that serve as a transparent medium for augmenting our natural skills of interaction with the world, instead of requiring conscious attention to the interface as an opaque object in the world.

Determination of Doxazosin Mesylate in Tablets by RP-HPLC

A simple, precise and rapid RP-HPLC method was developed for the determination of doxazosin mesylate in pharmaceutical formulations. The method was carried out on a Chromolith RP-C₁₈ column using a mixture of potassium phosphate buffer and methanol (40:60 v/v) and detection was done at 251 nm. The linearity range was 1-5 μg/ml. The retention time of the drug was 3.8 min. The LOD and LOQ were found to be 0.1 μg/ml and 0.5 μg/ml, respectively.

Role of Biopsy from Gastric Corpus in Diagnosis of Helicobacter pylori Infection in Patients on Acid Suppression Therapy

There are reports of migration of Helicobacter pylori from the gastric antrum to the proximal stomach following acid suppression therapy. The diagnosis of H pylori infection is usually based on rapid urease test and histology of gastric antral biopsies. 50 consecutive patients of peptic ulcer, 22 on proton pump inhibitors and 28 on histamine-2 receptor antagonists for at least 4 weeks were subjected to biopsies from the gastric corpus in addition to the antrum at the time of upper gastrointestinal endoscopy. H pylori infection was detected in 42 (84%) patients. The diagnosis was established from both antral and corpus biopsies in 34 (68%) and only antrum in 4 (8%). In 4 patients, 3 on proton pump inhibitors and one on H-2 receptor antagonists, H pylori was isolated only from the corpus. The rapid urease test was positive at a mean time of 67.6 minutes from the antrum as compared to 234.6 minutes from the corpus. Testing for H pylori from the antrum alone and not the corpus would have resulted in a false negative result in 8% patients. Biopsy from the gastric antrum should always be combined with biopsy from gastric corpus for the diagnosis of H pylori infection in patients with dyspepsia on acid suppression therapy.

Protein-coding and microRNA biomarkers of recurrence of prostate cancer following radical prostatectomy

An important challenge in prostate cancer research is to develop effective predictors of tumor recurrence following surgery to determine whether immediate adjuvant therapy is warranted. To identify biomarkers predictive of biochemical recurrence, we isolated the RNA from 70 formalin-fixed, paraffin-embedded radical prostatectomy specimens with known long-term outcomes to perform DASL expression profiling with a custom panel that we designed of 522 prostate cancer-relevant genes. We identified a panel of 10 protein-coding genes and two miRNA genes (RAD23B, FBP1, TNFRSF1A, CCNG2, NOTCH3, ETV1, BID, SIM2, LETMD1, ANXA1, miR-519d, and miR-647) that could be used to separate patients with and without biochemical recurrence (P < 0.001), as well as for the subset of 42 Gleason score 7 patients (P < 0.001). We performed an independent validation analysis on 40 samples and found that the biomarker panel was also significant at prediction of biochemical recurrence for all cases (P = 0.013) and for a subset of 19 Gleason score 7 cases (P = 0.010), both of which were adjusted for relevant clinical information including T-stage, prostate-specific antigen, and Gleason score. Importantly, these biomarkers could significantly predict clinical recurrence for Gleason score 7 patients. These biomarkers may increase the accuracy of prognostication following radical prostatectomy using formalin-fixed specimens.

Role of the BCA2 ubiquitin E3 ligase in hormone responsive breast cancer

The BCA2 protein contains a RING H2 finger and a Zn finger near the N-terminus and has E3 ligase activity. RING finger proteins play critical roles in mediating the transfer of ubiquitin and ubiquitin like modifiers to heterologous substrates as well as to the RING finger proteins themselves. Protein modification by ubiquitin and small ubiquitin-related modifier (SUMO) plays a pivotal role in protein homeostasis and is critical to regulating basic cellular processes such as proliferation, differentiation, apoptosis, intracellular signaling, and gene-transcriptional regulation. The addition of ubiquitin or SUMO can modulate the ability of proteins to interact with their partners, alter their patterns of sub-cellular localization and control their stability. It is clear that SUMO influences many different biological processes however recent data suggest that it is specifically important in the regulation of transcription. BCA2 is an E3 ligase that interacts with the SUMO conjugating enzyme Ubc9. It could therefore function as an E3 in the sumoylation of various transcription factors. We have found that the BCA2 is co-expressed with the estrogen receptor in 74% of ER-positive invasive ductal carcinomas from a 635 member breast cancer cohort (p = 0.004). At the cellular level, BCA2 co-localizes with ER and it appears that at the transcriptional level BCA2 mRNA expression is regulated by estrogen. Bioinformatic analysis of the BCA2 promoter region revealed ER and PR binding sites as well as that of other more general transcription factors. The data presented here provides an overview of the potential involvement of the BCA2 in hormone responsive breast cancer and opens up avenues that should be exploited to better understand the regulation of ER expression, growth of breast cancer cells, and the importance of BCA2.

Abstract 4599: The RING E3 ligase BCA2 is regulated by estrogen and co-expressed with estrogen receptor in breast cancer cells

The Breast Cancer Associated gene 2 (BCA2) protein contains a RING H2 finger and a zinc finger near the N-terminus. The presence of the RING domain allows BCA2 to function as an E3 ligase. RING finger proteins play critical roles in mediating the transfer of ubiquitin and ubiquitin-like modifiers to substrates; such modifications are pivotal in regulating protein homeostasis and basic cellular processes such as gene-transcriptional regulation. The RING domain in BCA2 is known to act as an E3 ligase in its auto-regulation, and is suspected to play a role in the modification of other proteins. In a cohort of 945 primary invasive breast cancers examined for estrogen receptor-alpha (ER) and BCA2 expression, 67% were found to be ER-positive, 74% of which also exhibited strong nuclear BCA2 protein expression (p = 0.004). In this study, we examined potential mechanism(s) underlying BCA2 and ER co-expression at transcriptional and protein levels. Estrogen-responsive and non-responsive breast cancer cell lines were used as model systems. To investigate whether BCA2 is an estrogen responsive gene, BCA2 and ER-positive T47D breast cancer cells were cultured in medium containing charcoal-stripped fetal calf serum supplemented with 10 nM and 100 nM 17β-estradiol respectively over a 72-hour time course. Northern and Western blots showed a 17β-estradiol-associated induction of BCA2 mRNA and protein within 72 hrs. Moreover, when ER is ectopically or stably expressed in ER and BCA2-negative MDA-MB-231 cells, prominent BCA2 expression is detected, suggesting that ER is responsible for induction of BCA2 transcription. To investigate a possible interaction of BCA2 and ER at a transcriptional level, bioinformatic analysis of the BCA2 promoter region revealed ER and PR binding sites as well as possible sites of general transcription factors.

Together our data indicates that BCA2 is upregulated in response to estrogen and that BCA2 expression can be rescued by the introduction of ER, suggesting that ER and BCA2 may be participating in crosstalk at the transcriptional level. Further investigations into this phenomenon are necessary to determine the possibility of the development of drugs targeting BCA2 in order to manipulate ER.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 4599.

The RING finger protein11 binds to Smad4 and enhances Smad4-dependant TGF-beta signalling

BACKGROUND

In breast carcinomas, prolonged signalling through the TGF-beta receptor promotes latent tumour progression, metastasis and the epithelial-to-mesenchymal transition of tumour cells. Previously, it has been found that the 154 amino acid RING finger protein, RNF11, was overexpressed in high-grade breast tumours and was capable of modulating TGF-beta signalling.

MATERIALS AND METHODS

Utilizing cellular and biochemical assays, key interactions and molecular roles for the RNF11 protein in the TGF-beta pathway were explored.

RESULTS

It is shown that RNF11 is required for TGF-beta signalling and is capable of enhancing the Smad-TGF-beta signalling pathway directly. Further, that endogenous RNF11 and Smad4 proteins associate and co-localize in a TGF-beta-enhanced manner. This study indicates that RNF11 induces an increase in Smad4 protein levels. In functional assays, it is observed that RNF11 enhances Smad4-dependant TGF-beta signalling and that RNF11 alone can recapitulate Smad4-dependant apoptosis in cellular assays.

CONCLUSION

RNF11 acts directly on Smad4 to enhance Smad4 function, and plays a role in prolonged TGF-beta signalling and possibly in latent tumour progression.

Epidemiological and clinical profile of irritable bowel syndrome in India: report of the Indian Society of Gastroenterology Task Force

AIMS

To study the profile of irritable bowel syndrome (IBS), and the frequency of such symptoms among the general population, in India.

METHODS

In this prospective, multi-center study, data were obtained from 2785 patients with chronic lower gastrointestinal symptoms (complainants) with no alarm feature and negative investigations for organic causes visiting physicians at 30 centers, and from 4500 community subjects (non-complainants), using separate questionnaires.

RESULTS

Most complainants were middle-aged (mean age 39.4 years) and male (1891; 68%). The common symptoms were: abdominal pain or discomfort (1958; 70%), abdominal fullness (1951; 70%); subjective feeling of constipation (1404 of 2656; 53%), or diarrhea (1252 of 2656, 47%), incomplete evacuation (2134; 77%), mucus with stools (1506; 54%), straining at stools (1271; 46%), epigastric pain (1364; 49%) and milk intolerance (906; 32%). Median stool frequency was similar in patients who felt they had constipation or those who felt they had diarrhea. Information to subtype symptoms using standard criteria was available in 1301 patients; of these, 507 (39%) had constipation-predominant IBS ( 3 <or= stools/week), 50 (4%) had diarrhea-predominant IBS (>3 stools/day) and 744 (57%) had indeterminate symptoms. Among non-complainants, most subjects reported daily defecation frequency of one (2520 [56%]) or two (1535 [34%]). Among non-complainants, 567 (12.6%) reported abdominal pain, 503 (11%) irregular bowel, 1030 (23%) incomplete evacuation, 167 (4%) mucus and 846 (18%) straining at stools; a combination of abdominal pain or discomfort relieved by defecation, and incomplete evacuation was present in 189/4500 (4.2%) community subjects.

CONCLUSIONS

Most patients with IBS in India are middle-aged men, and have a sense of incomplete evacuation and mucus with stools. Abdominal pain or discomfort is frequent but not universal. Importantly, stool frequency was similar irrespective of whether the patients felt having constipation or diarrhea. Most (90%) non-complainant subjects had 1 or 2 stools per day; symptoms complex suggestive of IBS was present in 4.2% of community subjects.

IL-6 enhances the nuclear translocation of DNA cytosine-5-methyltransferase 1 (DNMT1) via phosphorylation of the nuclear localization sequence by the AKT kinase

The epigenetic programming of genomic DNA is accomplished, in part, by several DNA cytosine-5-methyltransferases that act by covalently modifying cytosines with the addition of a methyl group. This covalent modification is maintained by the DNA cytosine-5-methyltransferase-1 enzyme (DNMT1), which is capable of acting in concert with other similar enzymes to silence important tumor suppressor genes. IL-6 is a multifunctional mediator of inflammation, acting through several major signaling cascades, including the phosphatidylinositol-3-kinase pathway (PI-3-K), which activates protein kinase B (AKT/PKB) downstream. Here, we show that the subcellular localization of DNMT1 can be altered by the addition of IL-6, increasing the rate of nuclear translocation of the enzyme from the cytosolic compartment. The mechanism of nuclear translocation of DNMT1 is greatly enhanced by phosphorylation of the DNMT1 nuclear localization signal (NLS) by PKB/AKT kinase. Mutagenic alteration of the two AKT target amino acids within the NLS results in a major loss of DNMT1 nuclear translocation, while the creation of a "phospho-mimic" amino acid (mutation to acidic residues) restores this compartmentation ability. These observations suggest an interesting hypothesis regarding how mediators of chronic inflammation may disturb the delicate balance of cellular compartmentalization of important proteins, and reveals a potential mechanism for the induction or enhancement of tumor growth via alteration of the components involved in the epigenetic programming of a cell.

Protein-c deficiency presenting with subacute intestinal obstruction due to mesenteric vein thrombosis

We describe a patient with protein C deficiency who presented with subacute intestinal obstruction due to ischaemic small bowel stricture. The patient also had left sided ileofemoral thrombosis. Venous thrombosis at unusual sites especially if associated with deep vein thrombosis of lower limb warrants a thorough screen for underlying thrombophilia. This, however, is a rare cause for ischaemic small bowel stricture.

Genetic and expression aberrations of E3 ubiquitin ligases in human breast cancer

Recent studies revealed that E3 ubiquitin ligases play important roles in breast carcinogenesis. Clinical research studies have found that (epi)-genetic (deletion, amplification, mutation, and promoter methylation) and expression aberration of E3s are frequent in human breast cancer. Furthermore, many studies have suggested that many E3s are either oncogenes or tumor suppressor genes in breast cancer. In this review, we provide a comprehensive summary of E3s, which have genetic and/or expression aberration in breast cancer. Most cancer-related E3s regulate the cell cycle, p53, transcription, DNA repair, cell signaling, or apoptosis. An understanding of the oncogenic potential of the E3s may facilitate identifying and developing individual E3s as diagnosis markers and drug targets in breast cancer.

Novel RING E3 ubiquitin ligases in breast cancer

Defects in ubiquitin E3 ligases are implicated in the pathogenesis of several human diseases, including cancer, because of their central role in the control of diverse signaling pathways. RING E3 ligases promote the ubiquitination of proteins that are essential to a variety of cellular events. Identification of which ubiquitin ligases specifically affect distinct cellular processes is essential to the development of targeted therapeutics for these diseases. Here we discuss two novel RING E3 ligases, BCA2 and RNF11, that are closely linked to human breast cancer. BCA2 E3 ligase is coregulated with estrogen receptor and plays a role in the regulation of epidermal growth factor receptor (EGF-R) trafficking. RNF11 is a small RING E3 ligase that affects transforming growth factorbeta and EGF-R signaling and is overexpressed in invasive breast cancers. These two proteins demonstrate the complexity of RING E3 ligase interactions in breast cancer and are potential targets for therapeutic interventions.

A novel RING-type ubiquitin ligase breast cancer-associated gene 2 correlates with outcome in invasive breast cancer

The RING finger family of proteins possess ubiquitin ligase activity and play pivotal roles in protein degradation and receptor-mediated endocytosis. In this study, we examined whether the breast cancer-associated gene 2 (BCA2), a novel RING domain protein, has E3 ubiquitin ligase activity and investigated its expression status in breast tumors. The full-length BCA2 gene was cloned from the human breast cancer cell line MDA-MB-468. It encodes an open reading frame of 304 amino acids and contains a RING-H2 domain. BCA2 maps to chromosome 1q21.1, a region known to harbor cytogenetic aberrations in breast cancers. We found that the BCA2 protein has an intrinsic autoubiquitination activity, the hallmark of E3 ligases, whereas mutant RING protein is not autoubiquitinated. This indicates that the BCA2 ubiquitin ligase activity is dependent on the RING-H2 domain. Using tissue microarrays and immunohistochemistry, we found strong to intermediate BCA2 staining in 56% of 945 invasive breast cancers cases, which was significantly correlated with positive estrogen receptor status [odds ratio (OR), 1.51; P = 0.004], negative lymph node status (OR, 0.73; P = 0.02), and an increase in disease-free survival for regional recurrence (OR, 0.45; P = 0.03). Overexpression of BCA2 increased proliferation and small interfering RNA inhibited growth of T47D human breast cancer cells and NIH3T3 mouse cells. The autoubiquitination activity of BCA2 indicates that it is a novel RING-type E3 ligase. Its association with clinical measures and its effects on cell growth indicate that BCA2 may be important for the ubiquitin modification of proteins crucial to breast carcinogenesis and growth.

Risk Factors of Hepatotoxicity During Anti-tuberculosis Treatment

BACKGROUND

Antituberculosis treatment (ATT) induced hepato-toxicity is common, but risk factors predicting its development are poorly understood. The present study evaluates the clinical risk factors predicting the development of hepatotoxicity in Indian patients with tuberculosis on antituberculosis treatment.

METHODS

Three groups of patients were studied at three service hospitals over a 3 year period from 2000-2002. Patients given ATT were followed up with monthly LFTs. Consecutive patients who developed Liver dysfunction (rise in SGPT > 5 times upper limit of normal) were studied, along with matched controls who did not. Markers for hepatitis B were also noted in these patients once in 6 months. A third group of patients who did not receive ATT but were HBsAg positive, were also similarly followed up. The possible association of age and sex of the patient, alcoholism, unrecognized chronic liver disease, hepatitis B virus carrier status and nutritional status with ATT-induced hepatitis was assessed. Statistical analysis was carried out by Chi square test/Fisher's exact test using WHO provided software Epi Info 6. Sixty-nine patients with ATT-induced hepatotoxicity were prospectively studied. In addition 128 patients on anti-tuberculosis drugs without hepatotoxicity and 39 HBsAg carriers not on ATT were followed up for 1 year.

RESULTS

Age, Sex, history of alcohol intake and BMI were not found to be related to development of hepatotoxicity. Presence of HBV infection or an underlying silent chronic liver disease were found to significantly increase the risk of development of ATT-induced hepatotoxicity. Continuation of ATT after development of jaundice was associated with a high fatality rate. It was possible to re-introduce isoniazid in 96% and rifampicin in 88% of patients with ATT induced hepatotoxicity.

CONCLUSION

ATT-induced hepatitis is common and is potentially fatal. It is likely to occur in those with underlying silent chronic liver disease, HBV infection and have been given ATT without a definite evidence of tuberculosis. Discontinuation of ATT leads to rapid recovery in most cases and drugs can safely be introduced after recovery in a majority of cases.

Essential roles of IGFBP-3 and IGFBP-rP1 in breast cancer

Insulin and insulin-like growth factors (IGFs) have critical functions in growth regulatory signalling pathways. They are part of a tightly controlled network of ligands, receptors, binding proteins and their proteases. However, the system becomes uncontrolled in neoplasia. The insulin-like growth factor binding protein 3 (IGFBP-3) and the insulin-like growth factor binding protein-related protein 1 (IGFBP-rP1) have unique properties among the sixteen known members of the IGFBP superfamily. IGFBP-3 has very high affinity for IGFs (k(d) approximately 10(-10) M), it transports >75% of serum IGF-I and -II, whereas it's affinity for insulin is very low. On the other hand, IGFBP-rP1 binds insulin with very high affinity (500-fold higher compared to other IGFBPs), but has low affinity for IGF-I and -II proteins (k(d) = 3 x 10(-8) M). In this review, we have examined the roles of IGFBP-3 and IGFBP-rP1 in breast cancer, and discuss the potential impact of these two proteins in mammary carcinoma risk assessment and the development of treatments for breast cancer.

ETS family of genes in leukemia and Down syndrome

The human ETS2 and ERG genes are members of the ETS gene family, with sequence homology to the viral ets gene of the avian erythroblastosis retrovirus, E26. These genes are located on chromosome 21 and molecular genetic analysis of Down syndrome (DS) patients with partial trisomy 21 suggested that ETS2 may be a gene within the minimal DS genetic region. We have, in fact, been able to confirm the presence of the ETS2 gene dosage in triplicate occurring in occult human 21 chromosome abnormalities. It is known that ERG and ETS2 gene translocations occur in certain specific leukemias associated with defined chromosome rearrangements [e.g., t(8;21)]. Moreover, it is known that DS individuals are at greater risk for leukemic disease than their normal familial cohorts, implying that trisomy of that region of human chromosome 21 may play a role in the development of this type of neoplasia. The human ETS genes, first identified in our laboratory, are highly conserved, being found from lower organisms, like Drosophila and sea urchin, to humans. In mammals, the ETS genes are structurally distinct, located on separate chromosomes; they are transcriptionally active and differentially regulated. The ETS2 protein is phosphorylated and turns over with a half-life of approximately 20 min. After activation with the tumor promoter, TPA, the level of ETS2 elevates 5- to 20-fold. The properties of the ETS2 protein, such as nuclear localization, phosphorylation, rapid turnover, and response to protein kinase C, indicate that this protein belongs to a group of oncogene proteins thought to have regulatory functions in the nucleus. In the mouse thymus ets-1 and ets-2 are 8-10-fold higher, respectively, in the CD4+ subset than in other subsets examined, suggesting a role in T-cell development for these genes. Cells transfected with the cellular ets-2 gene, expressing higher levels of ets-2 products, showed a stimulated proliferation response, abolished their serum requirement and formed colonies in soft agar that could induce tumors in nude mice. Collectively, these data suggest that this family of genes might play a role in controlling specific steps of the signaling transduction pathway. Thus, the ETS genes, as other genes with homology to viral oncogenes, might be instrumental in regulating cellular growth and differentiation, as well as organismal development.

The ubiquitin-mediated protein degradation pathway in cancer: therapeutic implications

The highly conserved eukaryotic ubiquitin-proteasome system (UP-S) plays a pivotal role in protein homeostasis and is critical in regulating normal and cancer-related cellular processes. The hierarchical nature of the UP-S provides a rich source of molecular targets for specific intervention and has therefore arisen as a promising approach to innovative anticancer therapies. The first in class proteasome inhibitory agent Bortezomib (Velcade) has recently obtained regulatory approval for the treatment of multiple myeloma. Ubiquitin-mediated degradation is a complex process that is comprised of well defined steps involving ubiquitin-activating enzymes (E1s), ubiquitin-conjugating enzymes (E2s) and ubiquitin ligases (E3s). Although a single E1 activates the ubiquitin conjugation machinery, a large number of E2 conjugating enzymes and E3 ligases are now known to exist. Proteins tagged with ubiquitin are subsequently recognised by the proteasome for digestion and fragmentation. The enzymatic nature, multitude of E3s and their specific substrate recognition predestines them as therapeutic targets. This article will review known inhibitors of the proteasome and their molecular mechanisms as well as ongoing developments and promising avenues for targeting substrate-specific E3 ligases that are likely to yield a new class of therapeutics that will serve and complement the armamentarium of anticancer drugs.

Should one vaccinate patients with chronic liver disease for hepatitis A virus in India?

BACKGROUND

Hepatitis A virus (HAV) vaccination is recommended worldwide for patients with chronic liver disease to prevent decompensation due to superinfection with HAV. India being endemic for HAV, the prevalence of pre-existing antibodies against HAV due to subclinical exposure to the virus in childhood among patients with chronic liver disease may be high and, therefore, vaccination may not be needed. However, little data are available on the prevalence of HAV antibody among patients with chronic liver disease in India.

METHODS

All patients with chronic liver disease seen at Gastroenterology Center, Army Hospital R and R, New Delhi during the year 2002 and diagnosed to have either chronic liver disease were tested for the presence of IgG anti-HAV antibody in their sera (using a commercial ELISA kit). All patients with acute exacerbation or rapid deterioration of a preexisting chronic liver disease were separately studied for presence of IgM anti-HAV. In addition, a matched number of patients who attended the center due to diseases other than liver disease were also studied as controls.

RESULTS

One hundred and eighty seven patients of chronic liver disease and 89 controls were studied. Mean age of these two groups was 38.6 and 42.1 years and 153 (81.8%) and 78 (87.6%) of them were males respectively. Etiology of chronic liver disease was HBV infection in 91(48.7%), HCV infection in 62 (33.2%), autoimmune chronic hepatitis in 3 (1.6%), PBC in seven (3.7%) and cryptogenic 24 (12.8%). Of these 179 (95.7%) patients tested positive for IgG anti-HAV. A total of 37 hospitalisations in 29 patients were noted during the study period due to acute exacerbation of pre-existing chronic liver disease. None of these were positive for IgM anti-HAV, while 28 were positive for IgG anti-HAV. Among the controls, 87 controls (94.6%) were positive IgG anti-HAV. The prevalence of anti-HAV positivity was similar among patients with various etiologies.

CONCLUSION

Vaccination against HAV is not routinely required among patients with chronic liver disease in India as there is a very high prevalence of pre-existing antibodies in these patients. HAV superinfection as a cause of acute exacerbation of chronic liver disease was not seen in this.

Reversible segmental portal hypertension--an unusual presentation of abdominal tuberculosis in a renal transplant recipient

Infections are the commonest cause of morbidity and mortality in renal transplant recipients. In India, tuberculosis is a one such common infection in these patients and presents with protean manifestations. We report here a case of pyrexia of unknown origin (PUO) and segmental portal hypertension in a renal transplant recipient. Search for the cause of portal hypertension revealed abdominal tubercular lymphadenitis. Treatment with anti-tubercular therapy caused regression of segmental portal hypertension.

ACCURACY OF SERUM - ASCITES ALBUMIN GRADIENT IN THE AETIOLOGICAL DIAGNOSIS OF ASCITES

50 adults with ascites admitted to our hospital were studied. Simultaneous samples of ascitic fluid and blood were collected and subjected to analysis including ascitic fluid total protein and serum ascites albumin gradient The cut off value of serum-ascites albumin gradient for differentiating between high and low gradient was taken as 1.1 gm % and of ascitic fluid protein for differentiating exudate and transudate as 2.5 gm%. The sensitivity, specificity, positive predictive value and negative predictive value of high gradient and transudative ascites in diagnosing portal hypertension were 943%, 60%, 84.6%, 81.8% and 62.9%, 133%, 91.7% and 50% respectively. High gradient ascites is a sensitive test in the diagnosis of portal hypertension as a cause of ascites. The exudate-transudate approach has severe limitations in the differential diagnosis of ascites.

Recurrent diarrhea in children living in areas with high levels of nitrate in drinking water

Given that there was documented evidence of an association between diarrhea and high nitrate ingestion, the authors examined drinking water nitrate concentration and its possible correlation(s) with methemoglobin levels, cytochrome b5 reductase activity, and recurrent diarrhea. In addition, the authors studied histopathological changes in the intestines of rabbits in an animal model. Five village areas were studied, and nitrate concentrations (expressed in mg of nitrate per liter of water) of 26, 45, 95, 220, and 459 existed in the respective villages. The study included 88 randomly selected children who were 8 yr of age or younger; they represented 10% of the total population of each of the areas. Detailed histories of recurrent diarrhea were noted, and medical examinations were conducted. Cytochrome b5 reductase activity and methemoglobin levels were estimated biochemically. Collected data were analyzed statistically with Microsoft Excel software. In addition, the authors exposed rabbits to various levels of nitrate, and histopathological changes of the stomach and intestine (small and large) were evaluated. There was a strong relationship between nitrate concentration and recurrent diarrhea; 80% of the recurrent diarrhea cases were explained by nitrate concentration alone. In the rabbit intestines, lymphocytic infiltration and hyperplasia characterized the submucosa as nitrate concentrations increased.

Hepatopulmonary syndrome: prevalence and clinical profile

BACKGROUND

The hepatopulmonary syndrome (HPS) is defined as a triad of liver dysfunction, intrapulmonary vascular dilatations (IPVD) and arterial hypoxemia. There is paucity of Indian studies regarding the prevalence of IPVD and arterial hypoxemia particularly amongst patients with non-cirrhotic portal fibrosis (NCPF) and extrahepatic portal vein obstruction (EHPVO), where liver dysfunction is not a feature.

METHODS

All patients with portal hypertension and esophageal varices seen at a tertiary care hospital during 1995-98 were studied. Ultrasonography of abdomen, contrast-enhanced echocardiography (CEE), arterial blood gas analysis and assessment of alveolar-arterial oxygen gradient were done.

RESULTS

Of 138 patients with portal hypertension seen during the study period, 88 fulfilled the inclusion and exclusion criteria. These included 63 with cirrhosis, 15 with NCPF and 10 with EHPVO. CEE showed IPVD in 17 (27%) patients with cirrhosis, of which 11 (17.5%) fulfilled the criteria for HPS. IPVD were also noted in 4 (26.6%) cases of NCPF and 3 (30%) of EHPVO, though only 2 (13.3%) and 1 (10%) respectively had elevated alveolar-arterial gradient and liver dysfunction in addition. Age and sex distribution and duration of symptoms were not different in patients with HPS. Patients with HPS had higher incidence of dyspnea, platypnea, clubbing and spider nevi.

CONCLUSIONS

Hepatopulmonary syndrome is present in 17.5% of cirrhotics, 13.3% of patients with NCPF and 10% with EHPVO. Patients with HPS had significantly higher incidence of dyspnea, platypnea, clubbing and spider nevi.

GRANULOCYTE MACROPHAGE COLONY STIMULATING FACTOR IMPROVES IMMUNOGENECITY OF HEPATITIS B VACCINE IN HEMODIALYSIS PATIENTS

Only 20-50% of hemodialysis patients, develop protective antibodies following double dose Hepatitis B vaccination. Early reports suggest augmented response with concomitant use of Granulocyte macrophage colony stimulating factor (GMCSF). This study was done to assess the response rate to hepatitis B vaccine in hemodialysis patients with use of GMCSF. Seventeen patients were included in study, all received 40 mcg of hepatitis B vaccine at 0,1 and 2 months. Ten of these received 150 mcg of GMCSF with each dose of vaccine while 7 were taken as controls. Only one patient from control group (14.3%) while 5/10 (50%) patients from GMCSF group, developed protective antibodies, i.e. anti HBS titres > 10miu/ml (p < 0.05). Present study shows the beneficial effect of GMCSF when used as adjuvant with hepatitis B vaccine, in hemodialysis patients.

Recurrent acute respiratory tract infections in areas with high nitrate concentrations in drinking water

A review of the literature indicated an association among high nitrate ingestion, methemoglobinemia, and pathologic changes in bronchi and lung parenchyma. The present study examined a possible correlation among drinking water nitrate concentration, methemoglobin levels, cytochrome b(5) reductase activity, and acute respiratory tract infection with a history of recurrence (RRTI). Our study was conducted in five village units in the state of Rajasthan, India, with nitrate concentrations of 26, 45, 95, 222, and 459 mg NO(3) ion/L. We randomly selected 88 children. The children were up to 8 years of age, age matched, and represented 10% of the total population of these areas. We obtained detailed RRTI histories and conducted medical examinations. Methemoglobin levels and cytochrome b(5) reductase activity were estimated biochemically. The data collected were statistically analyzed using spreadsheet software on a personal computer. We observed strong interdependence between methemoglobin levels and RRTI in children up to 8 years of age. Methemoglobin levels alone explained 80% of the variation in the RRTI cases. This study indicates that methemoglobinemia, secondary to high nitrate ingestion in drinking water, causes RRTI. Increased production of methemoglobin and free radicals of nitric oxide and oxygen due to nitrate metabolism in the body lead to alveolar damage and mismatching of ventilation and perfusion, which may be the reason for high mortality in children due to RRTI.

Recurrent acute respiratory tract infections in areas with high nitrate concentrations in drinking water

A review of the literature indicated an association among high nitrate ingestion, methemoglobinemia, and pathologic changes in bronchi and lung parenchyma. The present study examined a possible correlation among drinking water nitrate concentration, methemoglobin levels, cytochrome b(5) reductase activity, and acute respiratory tract infection with a history of recurrence (RRTI). Our study was conducted in five village units in the state of Rajasthan, India, with nitrate concentrations of 26, 45, 95, 222, and 459 mg NO(3) ion/L. We randomly selected 88 children. The children were up to 8 years of age, age matched, and represented 10% of the total population of these areas. We obtained detailed RRTI histories and conducted medical examinations. Methemoglobin levels and cytochrome b(5) reductase activity were estimated biochemically. The data collected were statistically analyzed using spreadsheet software on a personal computer. We observed strong interdependence between methemoglobin levels and RRTI in children up to 8 years of age. Methemoglobin levels alone explained 80% of the variation in the RRTI cases. This study indicates that methemoglobinemia, secondary to high nitrate ingestion in drinking water, causes RRTI. Increased production of methemoglobin and free radicals of nitric oxide and oxygen due to nitrate metabolism in the body lead to alveolar damage and mismatching of ventilation and perfusion, which may be the reason for high mortality in children due to RRTI.

Methaemoglobinaemia in areas with high nitrate concentration in drinking water

BACKGROUND

An epidemiological investigation was undertaken in all age groups to assess the prevalence of methaemoglobinaemia in areas with high nitrate concentration in drinking water.

METHODS

Five areas were selected with an average nitrate concentration (as nitrate) of 26, 45, 95, 222 and 459 mg nitrate ions/litre in drinking water. These areas were visited and the house schedule (containing name, age, sex and weight of the family members) prepared in accordance with the statistically designed protocol. In all, 178 persons, matched for age and weight, were selected and arranged in five age groups. They constituted 10% of the total population of each of these areas. A detailed history of the selected population was taken, medical examination conducted and blood samples taken to ascertain the level of methaemoglobin. The collected data were subjected to statistical analysis to ascertain a relationship between nitrate concentration and methaemoglobinaemia.

RESULTS

High nitrate concentrations cause severe methaemoglobinaemia (7%-27% of Hb) in all age groups, especially in the age group of less than 1 year and above 18 years. The lower levels of methaemoglobin in the age group of 1-18 years is probably due to better reserve of cytochrome b5 reductase activity and its adaptation to increasing nitrate concentration in water to compensate for methaemoglobinaemia in this age group.

CONCLUSION

We conclude that high nitrate ingestion causes methaemoglobinaemia in all age groups. Cytochrome b5 reductase activity and its adaptation with increasing water nitrate ingestion plays a role in compensating for the methaemoglobinaemia.

Epidemiological evaluation of recurrent stomatitis, nitrates in drinking water, and cytochrome b5 reductase activity

OBJECTIVE

Our aim was to examine a possible correlation between drinking water nitrate concentration, recurrent stomatitis, and cytochrome b5 reductase activity. Dietary nitrate can form nitrite in vivo. This can cause methemoglobinemia in the red blood cells. Cytochrome b5 reductase is an enzyme in the red blood cells that reduces methemoglobin back to hemoglobin.

METHODS

Five areas were selected in the State of Rajasthan, India, having drinking water nitrate concentration (as nitrate) of 26, 45, 95, 222, and 459 mg of NO3/L. House schedules were prepared in these areas in accordance with a statistically designed protocol. We selected 193 age- and weight-matched persons, representing 10% of the total population in each of these areas. Detailed history was taken for recurrent stomatitis, medical examination was conducted, and blood samples were taken to ascertain cytochrome b5 reductase activity in the selected population. Collected data were statistically analyzed to ascertain a relationship between nitrate concentration, cytochrome b5 reductase activity, and percent stomatitis, using Microsoft Excel software.

RESULTS

This study suggests that there is a significant interdependence between drinking water nitrate concentration, cytochrome b5 reductase activity, and recurrent stomatitis.

CONCLUSION

Increased cytochrome b5 reductase activity primarily induced by the presence of high nitrate concentration in drinking water could be the cause for recurrent stomatitis.

Biomechanical analysis of flat and oblique tibial tubercle osteotomy for recurrent patellar instability

Both flat (Elmslie-Trillat) and oblique (Fulkerson) osteotomy techniques are successful in treating patellar instability episodes by moving the tibial tubercle medially. The oblique osteotomy also results in anterior displacement that decreases patellofemoral forces. Recent reports have described proximal tibial fractures occurring during early weightbearing after oblique osteotomy. We performed oblique and flat osteotomies on 13 pairs of fresh-frozen cadaveric knees. The knees were then tested to failure on a materials testing system by exerting a load through the quadriceps tendon at a rate of 1000 N/sec to simulate a stumble injury. The failure mechanism for flat osteotomies was more likely to be tubercle "shingle" fracture, while oblique osteotomies more frequently failed through a tibial fracture or fixation failure in the posterior tibial cortex. Mean load to failure was significantly higher in the flat osteotomy specimens (1639 N versus 1166 N), as was total energy to failure (224 N.m versus 127 N.m). There was no significant difference in stiffness (87 N/cm versus 74 N/cm). We recommend the flat osteotomy for patients with isolated recurrent patellar instability and the oblique osteotomy in patients who have concomitant patellofemoral pain or articular degenerative changes. When an oblique osteotomy is used, we recommend postoperative brace protection and restricted weightbearing until the osteotomy heals.

Adaptation of cytochrome-b5 reductase activity and methaemoglobinaemia in areas with a high nitrate concentration in drinking-water

An epidemiological investigation was undertaken in India to assess the prevalence of methaemoglobinaemia in areas with high nitrate concentration in drinking-water and the possible association with an adaptation of cytochrome-b5 reductase. Five areas were selected, with average nitrate ion concentrations in drinking-water of 26, 45, 95, 222 and 459 mg/l. These areas were visited and house schedules were prepared in accordance with a statistically designed protocol. A sample of 10% of the total population was selected in each of the areas, matched for age and weight, giving a total of 178 persons in five age groups. For each subject, a detailed history was documented, a medical examination was conducted and blood samples were taken to determine methaemoglobin level and cytochrome-b5 reductase activity. Collected data were subjected to statistical analysis to test for a possible relationship between nitrate concentration, cytochrome-b5 reductase activity and methaemoglobinaemia. High nitrate concentrations caused methaemoglobinaemia in infants and adults. The reserve of cytochrome-b5 reductase activity (i.e. the enzyme activity not currently being used, but which is available when needed; for example, under conditions of increased nitrate ingestion) and its adaptation with increasing water nitrate concentration to reduce methaemoglobin were more pronounced in children and adolescents.

A novel transcription factor, ELF5, belongs to the ELF subfamily of ETS genes and maps to human chromosome 11p13-15, a region subject to LOH and rearrangement in human carcinoma cell lines

The ETS transcription factors are a large family implicated in the control of cellular proliferation and tumorigenesis. In addition, chromosomal translocations involving ETS family members are associated with a range of different human cancers. Given the extensive involvement of ETS factors in tumorigenesis, it becomes important to identify any additional ETS genes that may also play oncogenic roles. We identify a novel gene, ELF5, that appears to belong to the ELF (E74-like-factor) subfamily of the ETS transcription factor family, based upon similarity within the 'ETS domain'. ELF5 displays a similar, but more restricted, expression pattern to that of the newly isolated epithelium-specific ETS gene, ELF3. Unlike most other ETS family members, ELF5 is not expressed in hematopoietic compartments, but is restricted to organs such as lung, stomach, kidney, prostate, bladder and mammary gland. ELF5 is localized to human chromosome 11p13-15, a region that frequently undergoes loss of heterozygosity (LOH) in several types of carcinoma, including those of breast, kidney and prostate. We find that ELF5 expression is not detectable in a number of carcinoma cell lines, some of which display loss or rearrangement of an ELF5 allele. Similar to other ETS family members, ELF5 displays specific binding to DNA sequences containing a GGAA-core. In addition, ELF5 is able to transactivate through these ETS sequences, present upstream from a minimal promoter. Our data suggest that ELF5 may play roles in mammary, lung, prostate and/or kidney function, and possibly also in tumorigenesis.

Prognostic evaluation of early indicators in fulminant hepatic failure by multivariate analysis

Viral hepatitis is the commonest cause of fulminant hepatic failure (FHF) in developing countries. We evaluated the early indicators of prognosis in these patients by multivariate analysis. The records of 204 consecutive patients with acute liver failure admitted with hepatic encephalopathy over five years were studied. The etiology of these patients included virus related in 186 (91.1%), drug induced in 15 (7.4%), Wilson's disease in one (0.5%), acute Budd-Chiari syndrome in one (0.5%), and malignant infiltration in one (0.5%). Patients with FHF complicating viral hepatitis were analyzed by univariate and multivariate analysis. These patients were further subclassified depending upon the interval between the onset of jaundice and the onset of encephalopathy into hyperacute (HALF; interval 0-7 days), acute (ALF; interval 8-28 days) and subacute liver failure (SALF; interval 4-12 weeks). Sixty (32.3%) patients with viral hepatitis survived. Univariate analysis showed that the interval between onset of encephalopathy and onset of jaundice, grade of encephalopathy, raised intracranial pressure, prothrombin time, and serum bilirubin levels on admission were related to outcome in these patients. Multivariate logistic regression analysis showed that the presence of raised intracranial pressure at the time of admission, prothrombin time >100 sec on admission, age (>50 yr), and onset of encephalopathy seven days after onset of jaundice were associated with poor prognosis. Forty seven (37.0%) of 129 patients with HALF survived compared with 9 (22.5%) of 40 with ALF and 4 (21.1%) of 19 with SALF (P = NS). Raised intracranial pressure was more frequent in patients with HALF (48.8%) than in patients with ALF (32.5%) and SALF (15.8%; P = 0.01), while clinically detectable ascites was more frequent in patients with SALF (78.9%) compared with HALF (19.7%) and ALF (37.5%; P < 0.0001). The factors adversely affecting the outcome in our patients with FHF complicating viral hepatitis include presence of overt clinical features of raised ICP at the time of hospitalization, prothrombin time (>100 sec) on admission, age (>50 yr), and onset of encephalopathy seven days after onset of jaundice.

Orbital blow-out fractures: correlation of preoperative computed tomography and postoperative ocular motility

BACKGROUND/PURPOSE

Although the management of orbital blow-out fractures was controversial for many years, refined imaging with computed tomography (CT) helped to narrow the poles of the debate. Many orbital surgeons currently recommend repair if fracture size portends late enophthalmos, or if diplopia has not substantially resolved within 2 weeks of the injury. While volumetric considerations have been generally well-served by this approach, ocular motility outcomes have been less than ideal. In one series, almost 50% of patients had residual diplopia 6 months after surgery. A fine network of fibrous septa that functionally unites the periosteum of the orbital floor, the inferior fibrofatty tissues, and the sheaths of the inferior rectus and oblique muscles was demonstrated by Koornneef. Entrapment between bone fragments of any of the components of this anatomic unit can limit ocular motility. Based on the pathogenesis of blow-out fractures, in which the fibrofatty-muscular complex is driven to varying degrees between bone fragments, some measure of soft tissue damage might be anticipated. Subsequent intrinsic fibrosis and contraction can tether globe movement, despite complete reduction of herniated orbital tissue from the fracture site. We postulated that the extent of this soft tissue damage might be estimated from preoperative imaging studies.

METHODS

Study criteria included: retrievable coronal CT scans; fractures of the orbital floor without rim involvement, with or without extension into the medial wall; preoperative diplopia; surgical repair by a single surgeon; complete release of entrapped tissues; and postoperative ocular motility outcomes documented with binocular visual fields (BVFs). Thirty patients met all criteria. The CT scans and BVFs were assessed by different examiners among the authors. Fractures were classified into 3 general categories and 2 subtypes to reflect the severity of soft tissue damage within each category. "Trap-door" injuries, in which bone fragments appeared to have almost perfectly realigned, were classified as type I fractures. In the I-A subtype, no orbital tissue was visible on the sinus side of the fracture line. In the I-B subtype, soft tissue with the radiodensity of orbital fat was visible within the maxillary sinus. In type II fractures, bone fragments were distracted and soft tissue was displaced between them. In the II-A subtype, soft tissue displacement was less than, or proportional to, bone fragment distraction. In the II-B subtype, soft tissue displacement was greater than bone fragment distraction. In type III fractures, displaced bone fragments surrounded displaced soft tissue in all areas. In the III-A subtype, soft tissue and bone were moderately displaced. In the III-B subtype, both were markedly displaced. Motility outcomes were quantified by measuring the vertical excursion in BVFs. The interval between trauma and surgical repair was also determined.

RESULTS

Among the 15 patients with a motility outcome in BVFs which was poorer than the median (86 degrees or less of single binocular vertical excursion), 4 patients (27%) had type A fractures; 11 patients (73%) had type B fractures. Among the 15 patients with a better outcome than the median (88 degrees or more), 10 patients (67%) had type A fractures; 5 patients (33%) had type B fractures. These differences became more defined as analysis moved away from the median. Among 5 patients with type B fractures and better than the median result in BVFs, 3 patients (60%) had surgical repair during the first week after injury. Among the 11 patients with type B fractures and less than the median result, 1 patient (9%) had repair during the first week.

CONCLUSIONS

When the CT-depicted relationship between bone fragments and soft tissues is considered, a wide spectrum of injuries is subsumed under the rubric of blow-out fractures. In general, greater degrees of soft tissue incarceration or displacement, with presumably greater intrinsic damage and subsequent fibrosis, appear to result in poorer motility outcomes. Although this retrospective study does not conclusively prove its benefit, an urgent surgical approach to selected injuries should be considered.