Diagnosis of cancer multidrug resistance by bacterium-mediated imaging

Multidrug resistance (MDR) is a phenomenon expressed by many tumors affecting the chemotherapy efficacy, treatment decision, and the disease prognosis. Considering its great implication, non-invasive approaches are needed to identify this phenomenon in early stages of the disease. This article discusses the potential of the emerging non-invasive bacterium-mediated imaging of cancer in diagnosis of MDR. This potential is derived from the effect of cancer MDR on the pharmacokinetics of certain antibiotics, which are substrates of the MDR proteins. Since MDR proteins actively pump their substrates outside the resistant cancer cells, the elimination of the employed reporter bacteria, proliferating within MDR cancer cells, would require a larger dose of these antibiotics compared to those inside non-MDR cancer cells. These bacteria bear reporter genes that produce specific signals such as bioluminescent, fluorescent, magnetic, or radioactive signals that can be detected by non-invasive imaging modalities. Therefore, the presence, degree, and mechanism of MDR can be estimated by comparing the concentration of the employed antibiotic, required to cease these signals (reflecting the elimination of the bacteria), to a pre-determined reference. The real time imaging of MDR cancer and the early diagnosis of MDR, offered by this approach, would provide a better tool for preclinical studies of MDR, and allow a prompt choice of the most appropriate therapy.     

The role of aquaporin-1 in idiopathic and drug-induced intracranial hypertension

Idiopathic intracranial hypertension is a common disorder affecting mainly healthy, young, overweight women. The pathogenesis of this condition is unknown, but it has been shown to follow treatment with several compounds including corticosteroids and vitamin A derivatives. This paper will offer a novel hypothesis and insight on the pathogenesis of drug induced intracranial hypertension following a review and analysis of the literature. Both corticosteroids and vitamin A derivatives have been shown to upregulate the expression of aquaporin 1, a water channel protein. Aquaporin 1 is widely distributed in the human brain and is associated with water secretion into the subarachnoid space. Aquaporin 1 was also shown to participate in the regulation of weight. Agents used for treating idiopathic intracranial hypertension reduce aquaporin 1 expression. Based on these observations, we propose that aquaporin 1 has a pathogenetic role in drug induced idiopathic intracranial hypertension. Over expression of this gene causes increased intracranial pressure, and downregulation reduces pressure and alleviates the symptomatology and complications of idiopathic intracranial hypertension.     

Disturbed sleep in bipolar disorder is related to an elevation of IL-6 in peripheral monocytes

Bipolar disorder is a severe psychiatric disorder that is associated with persistent changes in the quality, duration and architecture of sleep. Currently there is no unifying hypothesis explaining the alterations in sleep observable in patients with bipolar disorder and management is often difficult though vital.Sleep is modified by various cytokines including IL-6. Elevated levels of IL-6 are associated with a poorer quality of sleep and changes in the architecture of sleep similar to those observed in bipolar disorder. Therapeutic administration of Interferon causes elevations of intrathecal IL-6 concentrations and appears to provoke a deteriorating quality of sleep. The blockade of IL-6 with tocilizumab in rheumatoid arthritis is associated with improvements in the quality of sleep.Bipolar disorder is associated with elevated levels of IL-6 and in particular elevated levels of mRNA coding for IL-6 in peripheral monocytes.We propose that the changes observed in the sleep of patients with bipolar disorder are related to the elevation of IL-6 and that this correlates with an elevated expression of mRNA coding for IL-6 expression in peripheral monocytes.     

Is myopia another clinical manifestation of insulin resistance?

Myopia is a multifactorial visual refraction disease, in which the light rays from distant objects are focused in front of retina, causing blurry vision. Myopic eyes are characterized by an increased corneal curvature and/or ocular axial length. The prevalence of myopia has increased in recent decades, a trend that cannot be attributed exclusively to genetic factors. Low and middle income countries have a higher burden of refractive error, which we propose could be a consequence of a shorter exposure time to a westernized lifestyle, a phenomenon that may also explain the rapid increase in cardiometabolic diseases, such as diabetes, among those populations. We suggest that interactions between genetic, epigenetic and a rapidly changing environment are also involved in myopia onset and progression. Furthermore, we discuss several possible mechanisms by which insulin resistance may promote abnormal ocular growth and myopia to support the hypothesis that insulin resistance and hyperinsulinemia are involved in its pathogenesis, providing a link between trends in myopia and those of cardiometabolic diseases. There is evidence that insulin have direct ocular growth promoting effects as well an indirect effect via the induction of insulin-like growth factors leading to decreases insulin-like growth factor-binding protein, also implicated in ocular growth.     

Dehydroascorbic acid for the treatment of acute ischemic stroke

In animal models of acute ischemic stroke, intravenous dehydroascorbic acid (DHAA), unlike ascorbic acid (AA), readily enters brain and is converted in both normal and ischemic brain into protective ascorbic acid. When given parenterally DHAA minimizes infarct volume and facilitates functional recovery. I hypothesize the same effect will occur in humans with acute ischemic stroke. Efficacy in reducing infarct volume is demonstrable in mice and rats even when DHAA is infused three hours after the experimental infarct. Moreover, there is fivefold mechanistic rational for DHA beside excellent pharmacokinetics and rapid penetration of brain and conversion to protective AA: (1) in ischemic brain, there is a precipitous decline in AA which can be reversed by intravenous DHAA; (2) after reduction of DHAA to AA in both normal and ischemic brain, AA can reduce oxidized vitamin E and glutathione, other protectors of brain against damaging reactive oxygen species which build up in ischemic brain; (3) AA itself can protect brain against damaging reactive oxygen species; (4) AA is an essential cofactor for several enzymes in brain including ten-eleven translocase-2 which upregulates production of protective molecules like brain-derived neurotrophic factor; and (5) DHAA after conversion to AA prevents both lipid oxidation and presumably oxidation of other labile substances (e.g., dopamine) in ischemic brain. In terms of safety, based on all available animal information, DHAA is safe in the proposed dosing regimen. For human clinical trials, the methodology for conducting the proposed animal safety, clinical pharmacology and phase II efficacy studies is straightforward. Finally, if DHAA preserved brain substance and function in humans, it could be employed in pre-hospital stroke patients.     

WebBioBank: A new platform for integrating clinical forms and shared neurosignal analyses to support multi-centre studies in Parkinson’s Disease

BackgroundThe web-based systems available for multi-centre clinical trials do not combine clinical data collection (Electronic Health Records, EHRs) with signal processing storage and analysis tools. However, in pathophysiological research, the correlation between clinical data and signals is crucial for uncovering the underlying neurophysiological mechanisms. A specific example is the investigation of the mechanisms of action for Deep Brain Stimulation (DBS) used for Parkinson’s Disease (PD); the neurosignals recorded from the DBS target structure and clinical data must be investigated.ObjectiveThe aim of this study is the development and testing of a new system dedicated to a multi-centre study of Parkinson’s Disease that integrates biosignal analysis tools and data collection in a shared and secure environment.MethodsWe designed a web-based platform (WebBioBank) for managing the clinical data and biosignals of PD patients treated with DBS in different clinical research centres. Homogeneous data collection was ensured in the different centres (Operative Units, OUs). The anonymity of the data was preserved using unique identifiers associated with patients (ID BAC). The patients’ personal details and their equivalent ID BACs were archived inside the corresponding OU and were not uploaded on the web-based platform; data sharing occurred using the ID BACs. The system allowed researchers to upload different signal processing functions (in a .dll extension) onto the web-based platform and to combine them to define dedicated algorithms.ResultsFour clinical research centres used WebBioBank for 1 year. The clinical data from 58 patients treated using DBS were managed, and 186 biosignals were uploaded and classified into 4 categories based on the treatment (pharmacological and/or electrical). The user’s satisfaction mean score exceeded the satisfaction threshold.ConclusionsWebBioBank enabled anonymous data sharing for a clinical study conducted at multiple centres and demonstrated the capabilities of the signal processing chain configuration as well as its effectiveness and efficiency for integrating the neurophysiological results with clinical data in multi-centre studies, which will allow the future collection of homogeneous data in large cohorts of patients.     

GIST 2.0: A scalable multi-trait metric for quantifying population representativeness of individual clinical studies

The design of randomized controlled clinical studies can greatly benefit from iterative assessments of population representativeness of eligibility criteria. We propose a multi-trait metric - GIST 2.0 that can compute the a priori generalizability based on the population representativeness of a clinical study by explicitly modeling the dependencies among all eligibility criteria. We evaluate this metric on twenty clinical studies of two diseases and analyze how a study’s eligibility criteria affect its generalizability (collectively and individually). We statistically analyze the effects of trial setting, trait selection and trait summarizing technique on GIST 2.0. Finally we provide theoretical as well as empirical validations for the expected properties of GIST 2.0.     

Fissured tongue: A sign of tongue edema?

Fissured tongue (FT) is a condition frequently seen in the general population. Clinically, FT is characterized by grooves that vary in depth and are noted along the dorsal and/or dorsolateral aspects of the tongue. Furthermore, FT presents many enlarged, smooth filiform papillae and subepithelial inflammatory infiltration. Despite of many studies, the etiology of FT remains obscure. FT is believed to be a congenital anomaly associated with several disorders and with geographic tongue (GT).We hypothesize that FT is not a congenital anomaly, and FT with swollen filiform papillae may represent edema in the subepithelial tissue of the tongue.According to the literature, the difference in prevalence among different age groups indicates that FT is not a congenital disorder. FT appears to occur more commonly in adults, and it is very rare or not at all in children younger than 10 years old. An association between FT and GT is well established in the literature, supporting the results of previous authors suggesting that FT might be a consequence of GT. The most remarkable finding in the region of swollen papillae of FT samples has been the subepithelial infiltrates of polymorphonuclear leucocytes and lymphocytes causing the subepithelial edema. The clinically visible grooves and large edematic papillae clustered on the region of the fissures might be caused by the inflammation and edema underneath the epithelium.In the future, FT and GT must be researched together as two different entities of the same disease so that GT is a prestage of FT. The diagnosis of FT must be taken to consideration whether the tongue surface have smooth and swollen papillae or normal-appearing filiform papillae.     

Role of the Fyn −93A>G polymorphism (rs706895) in acute rejection after liver transplantation

The tyrosine kinase Fyn phosphorylates tyrosine residues on key targets involved in early T-cell signal transduction. T-cell signal transduction is one essential step for acute transplant rejection. The aim of this study was to evaluate the association of Fyn −93A>G single nucleotide polymorphism (SNP) (rs706895) with the susceptibility to acute rejection episodes in liver transplantation. In total, 72 liver transplant recipients with one biopsy proven acute rejection (S-BPAR), 56 with multiple BPAR (M-BPAR), 105 without BPAR (No-BPAR), and 145 healthy controls were enrolled in this case-control study. The SNP was genotyped by polymerase chain reaction–allele specific restriction enzyme analysis (PCR–ASRA) and was analyzed for a recessive and a dominant model. The Fyn −93G allele exhibits in healthy controls a statistically significant lower frequency than in liver recipients (18% vs. 24%; p = 0.046) or in liver recipients with BPAR (18% vs. 27%; p = 0.017). However, the genotype and allele frequencies of the Fyn −93A>G SNP demonstrate no significant differences between recipients with acute rejection episodes (S-BPAR and M-BPAR) and No-BPAR recipients. Thus our results provide no evidence that the Fyn −93A>G SNP contributes to the susceptibility to acute liver transplant rejection in a Caucasian population.     

IDOL,inducible degrader of low-density lipoprotein receptor,serves as a potential therapeutic target for dyslipidemia

Low-density lipoprotein cholesterol (LDL-C) is the hall marker for the atherosclerotic cardiovascular disease (ASCVD). It has been shown that over 70% of circulating LDL-C is metabolized through binding and activation of hepatic LDL receptor (LDLR). Genetic LDLR mutations cause hypercholesterolemia in the patients. Therefore, elevation of LDLR levels is beneficial for the treatment of dyslipidemia. LDLR expression is regulated by the SREBP2/PCSK9 pathways. Targeting SREBP2/PCSK9 pathways by statins and human monoclonal PCSK9 antibody has been shown to reduce the progression of ASVCD. Recent studies identified that inducible degrader of LDLR (IDOL) is a novel regulator of LDLR. IDOL is an E3-ubiquitin ligase regulated via liver X receptors (LXRs) binding to the upstream of translation start site of IDOL. IDOL modulates LDLR distribution through ubiquitination and degradation of LDLR in lysosomes. Genome-wide association studies (GWAS) have revealed that the nonsynonymous substitution rs9370867 of IDOL probably contributes to the variability of circulating LDL levels. Recently studies also demonstrated that IDOL influences PCSK9 expression in a LDLR/SREBP2-dependent manner. Based upon these novel findings, we hypothesize that IDOL and PCSK9 would have a synergistic effect on LDLR distribution. Specifically, loss of IDOL increases LDLR distribution in the hepatic cell, and subsequently reduces serum LDL-C levels in dyslipidemic patients. IDOL might be a potential therapeutic target for the treatment of ASCVD.     

Increased anal basal pressure in chronic anal fissures may be caused by overreaction of the anal-external sphincter continence reflex

Chronic anal fissure is a painful disorder caused by linear ulcers in the distal anal mucosa. Even though it counts as one of the most common benign anorectal disorders, its precise etiology and pathophysiology remains unclear. Current thinking is that anal fissures are caused by anal trauma and pain, which leads to internal anal sphincter hypertonia. Increased anal basal pressure leads to diminished anodermal blood flow and local ischemia, which delays healing and leads to chronic anal fissure. The current treatment of choice for chronic anal fissure is either lateral internal sphincterotomy or botulinum toxin injections.In contrast to current thinking, we hypothesize that the external, rather than the internal, anal sphincter is responsible for increased anal basal pressure in patients suffering from chronic anal fissure. We think that damage to the anal mucosa leads to hypersensitivity of the contact receptors of the anal-external sphincter continence reflex, resulting in overreaction of the reflex. Overreaction causes spasm of the external anal sphincter. This in turn leads to increased anal basal pressure, diminished anodermal blood flow, and ischemia. Ischemia, finally, prevents the anal fissure from healing.Our hypothesis is supported by two findings. The first concerned a chronic anal fissure patient with increased anal basal pressure (170 mmHg) who had undergone lateral sphincterotomy. Directly after the operation, while the submucosal anesthetic was still active, basal anal pressure decreased to 80 mmHg. Seven hours after the operation, when the anesthetic had completely worn off, basal anal pressure increased again to 125 mmHg, even though the internal anal sphincter could no longer be responsible for the increase. Second, in contrast to previous studies, recent studies demonstrated that botulinum toxin influences external anal sphincter activity and, because it is a striated muscle relaxant, it seems reasonable to presume that it affects the striated external anal sphincter, rather than the smooth internal anal sphincter.If our hypothesis is proved correct, the treatment option of lateral internal sphincterotomy should be abandoned in patients suffering from chronic anal fissures, since it fails to eliminate the cause of high anal basal pressure. Additionally, lateral internal sphincterotomy may cause damage to the anal-external sphincter continence reflex, resulting in fecal incontinence. Instead, higher doses of botulinum toxin should be administered to those patients suffering from chronic anal fissure who appeared unresponsive to lower doses.     

Physiological organization of immune response based on the homeostatic mechanism of matrix reprogramming: Implication in tumor and biotechnology

It is accepted that the immune system responds to pathogens with activation of antigen-independent innate and antigen-dependent adaptive immunity. However many immune events do not fit or are even inconsistent with this notion. We developed a new homeostatic model of the immune response. This model consists of four units: a sensor, a regulator, an effector and a rehabilitator. The sensor, macrophages or lymphocytes, recognize pathogenic cells and generate alarm signals. The regulator, antigen-presenting cells, Тregs and myeloid-derived suppressor cells, evaluate the signals and together with sensor cells program the effector. The effector, programmed macrophages and lymphocytes, eliminate the pathogenic cells. The rehabilitator, M2 macrophages, restrict inflammation, provide angiogenesis and reparation of tissue damage, and restore the homeostasis. We suggest the terms “immune matrix” for a biological template of immune responses to pathogens and “matrix reprogramming” for the interdependent reprogramming of different cells in the matrix. In an adequate immune response, the matrix forms a negative feedback mechanism to support the homeostasis. We defined the cellular and phenotypic composition of a tumor immune matrix. A tumor reprograms the homeostatic negative feedback mechanism of matrix into a pathogenic positive feedback mechanism. M2 macrophages play a key role in this transformation. Therefore, macrophages are an attractive target for biotechnology. Based on our hypotheses, we are developing a cell biotechnology method for creation of macrophages with a stable antitumor phenotype. We have shown that such macrophages almost doubled the survival time of mice with tumor.     

Predictive analysis for identifying potentially undiagnosed post-stroke spasticity patients in United Kingdom

Purpose of the researchSpasticity is one of the well-recognized complications of stroke which may give rise to pain and limit patients’ ability to perform daily activities. The predisposing factors and direct effects of post-stroke spasticity also involve high management costs in terms of healthcare resources, and case-control designs are required for establishing such differences. Using ‘The Health Improvement Network’ (THIN) database, such a study would not provide reliable estimates since the prevalence of post-stroke spasticity was found to be 2%, substantially below the most conservative previously reported estimates. The objective of this study was to use predictive analysis techniques to determine if there are a substantial number of potentially under-recorded patients with post-stroke spasticity.MethodsThis study used retrospective data from adult patients with a diagnostic code for stroke between 2007 and 2011 registered in THIN. Two algorithm approaches were developed and compared, a statistically validated data-trained algorithm and a clinician-trained algorithm.ResultsA data-trained algorithm using Random Forest showed better prediction performance than clinician-trained algorithm, with higher sensitivity and only marginally lower specificity. Overall accuracy was 75% and 72%, respectively. The data-trained algorithm predicted an additional 3912 records consistent with patients developing spasticity in the 12 months following a stroke.ConclusionsUsing machine learning techniques, additional unrecorded post-stroke spasticity patients were identified, increasing the condition’s prevalence in THIN from 2% to 13%. This work shows the potential for under-reporting of PSS in primary care data, and provides a method for improved identification of cases and control records for future studies.     

Thymic CCL2 influences induction of T-cell tolerance

Thymic epithelial cells (TEC) and dendritic cells (DC) play a role in T cell development by controlling the selection of the T cell receptor repertoire. DC have been described to take up antigens in the periphery and migrate into the thymus where they mediate tolerance via deletion of autoreactive T cells, or by induction of natural regulatory T cells. Migration of DC to thymus is driven by chemokine receptors. CCL2, a major ligand for the chemokine receptor CCR2, is an inflammation-associated chemokine that induces the recruitment of immune cells in tissues. CCL2 and CCR2 are implicated in promoting experimental autoimmune encephalomyelitis (EAE), a mouse model for multiple sclerosis. We here show that CCL2 is constitutively expressed by endothelial cells and TEC in the thymus. Transgenic mice overexpressing CCL2 in the thymus showed an increased number of thymic plasmacytoid DC and pronounced impairment of T cell development. Consequently, CCL2 transgenic mice were resistant to EAE. These findings demonstrate that expression of CCL2 in thymus regulates DC homeostasis and controls development of autoreactive T cells, thus preventing development of autoimmune diseases.     

Localization of Na+–K+-ATPase α/β, Na+–K+–2Cl-cotransporter 1 and aquaporin-5 in human eccrine sweat glands

In order to evaluate the function of the repaired or regenerated eccrine sweat glands, we must first localize the proteins involved in sweat secretion and absorption in normal human eccrine sweat glands. In our studies, the cellular localization of Na⁺–K⁺-ATPase α/β, Na⁺–K⁺–2Cl-cotransporter 1 (NKCC1) and aquaporin-5 (AQP5) in eccrine sweat glands were detected by immunoperoxidase labeling. The results showed that Na⁺–K⁺-ATPase α was immunolocalized in the cell membrane of the basal layer and suprabasal layer cells of the epidermis, the basolateral membrane of the secretory coils, and the cell membrane of the outer cells and the basolateral membrane of the luminal cells of the ducts. The localization of Na⁺–K⁺-ATPase β in the secretory coils was the same as Na⁺–K⁺-ATPase α, but Na⁺–K⁺-ATPase β labeling was absent in the straight ducts and epidermis. NKCC1 labeling was seen only in the basolateral membrane of the secretory coils. AQP5 was strongly localized in the apical membrane and weakly localized in the cytoplasm of secretory epithelial cells. The different distribution of these proteins in eccrine sweat glands was related to their functions in sweat secretion and absorption.     

The RND protein is involved in the vulnibactin export system in Vibrio vulnificus M2799

Vibrio vulnificus, an opportunistic marine bacterium that causes a serious, often fatal, infection in humans, requires iron for its pathogenesis. This bacterium exports vulnibactin for iron acquisition from the environment. The mechanisms of vulnibactin biosynthesis and ferric-vulnibactin uptake systems have recently been reported, while the vulnibactin export system has not been reported. Mutant growth under low-iron concentration conditions and a bioassay of the culture supernatant indicate that the VV1_0612 protein plays a crucial role in the vulnibactin secretion as a component of the resistance-nodulation-division (RND)-type efflux system in V. vulnificus M2799. To identify which RND protein(s) together with VV1_0612 TolC constituted the RND efflux system for vulnibactin secretion, deletion mutants of 11 RND protein-encoding genes were constructed. The growth inhibition of a multiple mutant (Δ11) of the RND protein-encoding genes was observed 6 h after the beginning of the culture. Furthermore, ΔVV1_1681 exhibited a growth curve that was similar to that of Δ11, while the multiple mutant except ΔVV1_1681 showed the same growth as the wild-type strain. These results indicate that the VV1_1681 protein is involved in the vulnibactin export system of V. vulnificus M2799. This is the first genetic evidence that vulnibactin is secreted through the RND-type efflux systems in V. vulnificus.