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Motor vehicles are the prime source of transportation where vehicles with A/C play a major part. This paper designs an embedded system for a vehicle cabin, which senses the gases like carbon-monoxide and oxygen and displayed at each and every second. If the level of the CO increases than the normal level (30 ppm) or the level of the oxygen decreases than the normal level (19%) then an alarm is generated automatically and also ventilation is provided immediately. A warning message is sent to the authorized user via GSM. The advantage of this system is proper detection and faster response time leading to faster diffusion of the situation, compared manual method. [ABSTRACT FROM AUTHOR]

Malabsorption of NaCl is the primary cause of diarrhea in inflammatory bowel disease (IBD). Coupled NaCl absorption occurs via the dual operation of Na:H and Cl:HCO 3 exchange in the brush border membrane (BBM) of villus cells. Cl:HCO 3 exchange is mediated by BBM transporters DRA (downregulated in adenoma) and PAT1 (putative anion transporter 1) in the mammalian small intestine. DRA/PAT1-mediated Cl:HCO 3 exchange was significantly downregulated in the BBM of villus cells in a rabbit model of chronic ileitis, while Na:H exchange was unaffected. The inhibition of Cl:HCO 3 exchange was restored in the rabbits when treated with a broad-spectrum immunomodulator, i.e. a glucocorticoid, indicating that the downregulation of DRA/PAT1 is likely to be immune-mediated during chronic enteritis. Mucosal mast cells are one type of key immune cells that are known to proliferate and release immune inflammatory mediators, thus playing a significant role in the pathogenesis of IBD. However, how mast cells may regulate DRA- and PAT1-mediated Cl:HCO 3 exchange in a rabbit model of chronic ileitis is unknown. In this study, treatment of rabbits with chronic intestinal inflammation with the mast cell stabilizer ketotifen did not affect the mucosal architecture of the inflamed intestine. However, ketotifen treatment reversed the inhibition of Cl:HCO 3 activity in the BBM of villus cells. This restoration of Cl:HCO 3 activity to normal levels by ketotifen was found to be secondary to restoring the affinity of the exchangers for its substrate chloride. This observation was consistent with molecular studies, where the mRNA and BBM protein expressions of DRA and PAT1 remained unaffected in the villus cells under all experimental conditions. Thus, this study indicates that mast cells mediated the inhibition of coupled NaCl absorption by inhibiting Cl:HCO 3 exchange in a rabbit model of chronic enteritis.

In the small intestine, sodium (Na) absorption occurs primarily via two apical transporters, Na-hydrogen exchanger 3 (NHE3) and Na-glucose cotransporter 1 (SGLT1). The two primary Na-absorptive pathways were previously shown to compensatorily regulate each other in rabbit and rat intestinal epithelial cells. However, whether NHE3 and SGLT1 regulate one another in normal human enterocytes is unknown, mainly due to a lack of appropriate experimental models. To investigate this, we generated 2D enterocyte monolayers from human jejunal 3D organoids and used small interfering RNAs (siRNAs) to knock down NHE3 or SGLT1. Molecular and uptake studies were performed to determine the effects on NHE3 and SGLT1 expression and activity. Knockdown of NHE3 by siRNA in enterocyte monolayers was verified by qPCR and Western blot analysis and resulted in reduced NHE3 activity. However, in NHE3 siRNA-transfected cells, SGLT1 activity was significantly increased. siRNA knockdown of SGLT1 was confirmed by qPCR and Western blot analysis and resulted in reduced SGLT1 activity. However, in SGLT1 siRNA-transfected cells, NHE3 activity was significantly increased. These results demonstrate for the first time the functionality of siRNA in patient-derived organoid monolayers. Furthermore, they show that the two primary Na absorptive pathways in human enterocytes reciprocally regulate one another.

Background Penile cancer is a rare malignancy usually requiring surgery to achieve oncological control of the primary tumour but often at the expense of functional length. The presenting stage of the primary is a crucial factor in determining the most appropriate surgical procedure. Accurate preoperative staging is essential, and current modalities include clinical and radiological assessment. Clinical staging can, however, be hampered by patient body habitus and unreliable for more advanced T4 tumours, whereas radiological staging allows for more detailed identification of tissue planes and tumour involvement. There is no clear consensus on the preferred imaging technique, although, in the current European Association of Urology penile cancer guidelines, MRI is recommended with the use of ultrasound when MRI is not available. It was recommended that having the penis in an erect state by the administration of intra-cavernosal prostaglandin gave a more detailed picture enabling a greater predictor of corporal involvement. Recent studies have, however, suggested that there may be no such advantage. Methodology A retrospective review was conducted of all patients who underwent surgery for penile cancer comparing the preoperative MRI stage with the final pathological stage between July 2009 and June 2023. In addition to the MRI, patients were given an intra-cavernosal injection of prostaglandin E1 to induce tumescence unless otherwise indicated. All imaging was reported by a single consultant uro-radiologist with surgery undertaken by a single surgeon and pathology reviewed through the supra-regional penile multidisciplinary team. Results A total of 136 penile cancer patients were included in the review. Within this cohort, 98 patients had an MRI without intra-cavernosal prostaglandin and the number who had Ta, T1, T2, T3 and T4 histopathological stages was 3, 31, 45, 18, and 1, respectively. The preoperative MRI stage had a low agreement with the final histological stage for early tumours, with sensitivities and specificity of 35% and 97% for T1 and 56% and 80% for T2, respectively. Sensitivity and specificity increased for cavernosal involvement at 83% and 95%, respectively. In addition, a further 38 patients had an MRI in conjunction with an injection of prostaglandin E1 which failed to show any diagnostic improvement in sensitivity or specificity in the preoperative MRI stage. Conclusions The use of MRI as a preoperative modality for staging penile cancer performs best for identifying tumour involvement of the cavernosal bodies. Performing the MRI with the penis erect with the use of an intra-cavernosal injection did not offer any additional benefit in accurately staging penile cancer., Competing Interests: The authors have declared that no competing interests exist., (Copyright © 2024, Iqbal et al.)

Polypropylene microplastics are the leading contaminant in aquatic environments, although research on their toxicity remains scarce. The proposed research focuses on the harmful consequences of acute exposure to polypropylene microplastics in Daphnia similis. This work converts widely available polypropylene bags into microplastics using xylene. FTIR findings demonstrated the lack of xylene residue in the produced polypropylene microplastic particles, which were spherical and ranged in size from 11.86 to 44.62 µm (FE-SEM). The results indicate that acute exposure to polypropylene microplastics causes immobility in D. similis. Ingestion of microplastics enhances the generation of reactive oxygen species (ROS), as shown by biochemical studies. Due to the production of free radicals in D. similis, the antioxidant enzymes superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GPx) and glutathione-S-transferase (GST) and a non-antioxidant enzyme of reduced glutathione (GSH) and also oxidative stress effects in lipid (lipid peroxidation - LPO), protein (carbonyl protein - CP) were increased. Additionally, the amount of the neurotransmitter enzyme acetylcholinesterase (AChE) activity was decreased. These findings indicate that the accumulation of polypropylene microplastics in the bodies of filter-feeding organisms should aggravate toxicity in the freshwater environment., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

Recently developed human intestinal epithelial 3D organoid cultures are a useful cell culture model to study intestinal transport physiology. From these, 2D monolayer cultures can be generated in which apical transporters are exposed to the medium, thereby better facilitating in vitro investigation of intestinal absorption processes. However, whether nutrient and electrolyte absorption can be physiologically regulated in human organoid-derived monolayers has not been determined. Constitutive nitric oxide (cNO) is known to regulate multiple gastrointestinal physiological functions. Previous studies using in vivo and in vitro mammalian animal models indicate that enhanced intracellular cNO differentially regulates the two primary apical Na transporters in small intestinal epithelial cells. Here, we generated human jejunal organoid-derived monolayers to determine whether apical nutrient and electrolyte transporter function is regulated by cNO in human enterocytes. Western blot analysis and immunocytochemical staining showed that organoid-derived 2D cultures express markers of enterocyte differentiation and form intact monolayers of apical-basal polarized epithelial cells. Uptake studies demonstrated that jejunal monolayers exhibit functional activity of Na-glucose cotransporter 1 (SGLT1; SLC5A1) and Na-H exchanger 3 (NHE3; SLC9A3). In response to physiological increases in cNO, the two primary apical Na transporters were differentially regulated in human intestinal organoid-derived monolayers, across multiple human specimens. An increase in cNO stimulated SGLT1, while NHE3 was inhibited. These results are similar to what is seen in vivo and in vitro in different animal intestinal models. Thus, human jejunal organoid-derived monolayers are an ideal in vitro model to better understand how intestinal nutrient absorption is regulated., (Copyright © 2022. Published by Elsevier Inc.)

In the small intestine, Na:H (NHE3) and Cl:HCO3 (DRA or PAT1) exchangers present in the brush border membrane (BBM) of absorptive villus cells are primarily responsible for the coupled absorption of NaCl, the malabsorption of which causes diarrhea, a common symptom of inflammatory bowel disease (IBD). Inducible nitric oxide (iNO), a known mediator of inflammation, is increased in the mucosa of the chronically inflamed IBD intestine. An SAMP1/YitFc (SAMP1) mouse, a spontaneous model of chronic ileitis very similar to human IBD, was used to study alterations in NaCl absorption. The SAMP1 and control AKR mice were treated with I-N(6)-(1-Iminoethyl)-lysine (L-NIL) to inhibit iNO production, and DRA/PAT1 and NHE3 activities and protein expression were studied. Though Na:H exchange activity was unaffected, Cl:HCO3 activity was significantly decreased in SAMP1 mice due to a reduction in its affinity for Cl, which was reversed by L-NIL treatment. Though DRA and PAT1 expressions were unchanged in all experimental conditions, phosphorylation studies indicated that DRA, not PAT1, is affected in SAMP1. Moreover, the altered phosphorylation levels of DRA was restored by L-NIL treatment. Inducible NO mediates the inhibition of coupled NaCl absorption by decreasing Cl:HCO3 but not Na:H exchange. Specifically, Cl:HCO3 exchanger DRA but not PAT1 is regulated at the level of its phosphorylation by iNO in the chronically inflamed intestine., (© 2021 Crohn’s & Colitis Foundation. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Over four billion episodes of diarrhea occur annually in developing countries with diarrheagenic Escherichia coli (DEC) outbreaks also being reported, until now bacterial diarrhea is conventionally addressed by the antibiotic treatment regimes. In recent decades, the emergence of antimicrobial-resistant strains has become a major obstacle in diarrheal treatment; hence, novel and ideal therapeutics are needed. Notably, 80% of DEC is resistant to first-class antibiotics. Among the existing strategies, passive immunization is considered as an alternative to combat drug-resistant bacteria. Antibodies specific to an antigen can be used for prophylactic and therapeutic purposes. In this review, we have systematically discussed the effect of passive immunotherapy to combat DEC and explored the types and advancements in antibodies used against antibiotic-resistant DEC.

Na-K-ATPase provides a favorable transcellular Na gradient required for the functioning of Na-dependent nutrient transporters in intestinal epithelial cells. The primary metabolite for enterocytes is glutamine, which is absorbed via Na-glutamine co-transporter (SN2; SLC38A5) in intestinal crypt cells. SN2 activity is stimulated during chronic intestinal inflammation, at least in part, secondarily to the stimulation of Na-K-ATPase activity. Leukotriene D4 (LTD4) is known to be elevated in the mucosa during chronic enteritis, but the way in which it may regulate Na-K-ATPase is not known. In an in vitro model of rat intestinal epithelial cells (IEC-18), Na-K-ATPase activity was significantly stimulated by LTD4. As LTD4 mediates its action via Ca-dependent protein kinase C (PKC), Ca levels were measured and were found to be increased. Phorbol 12-myristate 13-acetate (PMA), an activator of PKC, also mediated stimulation of Na-K-ATPase like LTD4, while BAPTA-AM (Ca chelator) and calphostin-C (Cal-C; PKC inhibitor) prevented the stimulation of Na-K-ATPase activity. LTD4 caused a significant increase in mRNA and plasma membrane protein expression of Na-K-ATPase α1 and β1 subunits, which was prevented by calphostin-C. These data demonstrate that LTD4 stimulates Na-K-ATPase in intestinal crypt cells secondarily to the transcriptional increase of Na-K-ATPase α1 and β1 subunits, mediated via the Ca-activated PKC pathway.

Aims: The present study aims to target the quorum sensing (QS) accessory gene regulator A (AgrA) of Staphylococcus aureus to curtail bacterial virulence through drug repurposing approach., Main Methods: In silico screening of chemical ligands that bind specifically to the S. aureus C-LytTR domain of AgrA (AgrA C ) was carried out. AgrA inhibition and downregulation of virulence genes linked to QS system of S. aureus were determined. Efficacy, dermal toxicity and drug tolerance induction were tested in Balb/C mice dermonecrosis model., Key Findings: Bumetanide bound to the conserved amino acid Tyr-229 of AgrA and showed 70% AgrA inhibition at 0.1 μM. Highly significant reduction in the expression of representative virulence genes such as alpha-hemolysin (~5 log 2 -fold), phenol-soluble modulins (~4 log 2 -fold) and panton-valentine leukocidin (~3 log 2 -fold) was noted in vitro. In vivo studies signified bumetanide to be highly effective in controlling the ulcer development and promoted wound healing. Also, the tested substance did not have dermal toxicity and no tolerance induction as well., Significance: Targeting the QS regulators could be a possible alternative approach to curtail virulence in S. aureus. In addition, if the QS inhibitors are repurposed it could accelerate the drug development process and reduce the cost. The identified drug bumetanide inhibited AgrA and the results were in comparable to that of a known virulence inhibitor, diflunisal. The newly reported results of bumetanide in this study are expected to mark the drug's visibility for antibiotic adjunctive therapy and topical drug formulations for skin infections research., (Copyright © 2021 Elsevier Inc. All rights reserved.)

The primary means of intestinal absorption of nutrients by villus cells is via Na-dependent nutrient co-transporters located in the brush border membrane (BBM). These secondary active co-transport processes require a favorable transcellular Na gradient that is provided by Na-K-ATPase. In chronic enteritis, malabsorption of essential nutrients is partially due to inhibition of villus Na-K-ATPase activity mediated by specific immune inflammatory mediators that are known to be elevated in the inflamed mucosa. However, how Prostaglandin E2 (PGE2), a specific mediator of nutrient malabsorption in the villus BBM, may mediate the inhibition of Na-K-ATPase is not known. Therefore, this study aimed to determine the effect of PGE2 on Na-K-ATPase in villus cells and define its mechanism of action. In vitro, in IEC-18 cells, PGE2 treatment significantly reduced Na-K-ATPase activity, accompanied by a significant increase in the intracellular levels of cyclic Adenosine Monophosphate (cAMP). The treatment with cAMP analog 8-Bromo-cAMP mimicked the PGE2-mediated effect on Na-K-ATPase activity, while Rp-cAMP (PKA inhibitor) pretreatment reversed the same. The mechanism of inhibition of PGE2 was secondary to a transcriptional reduction in the Na-K-ATPase α1 and β1 subunit genes, which was reversed by the Rp-cAMP pretreatment. Thus, the PGE2-mediated activation of the PKA pathway mediates the transcriptional inhibition of Na-K-ATPase activity in vitro.

Alzheimer's disease (AD) is a prevalently found tauopathy characterized by memory loss and cognitive insufficiency. AD is an age-related neurodegenerative disease with two major hallmarks which includes extracellular amyloid plaques made of amyloid-β (Aβ) and intracellular neurofibrillary tangles of hyperphosphorylated tau. With population aging worldwide, there is an indispensable need for treatment strategies that can potentially manage this developing dementia. Despite broad researches on targeting Aβ in the past two decades, research findings on Aβ targeted therapeutics failed to prove efficacy in the treatment of AD. Tau protein with its extensive pathological role in several neurodegenerative diseases can be considered as a promising target candidate for developing therapeutic interventions. The abnormal hyperphosphorylation of tau plays detrimental pathological functions which ultimately lead to neurodegeneration. This review will divulge the importance of tau in AD pathogenesis, the interplay of Aβ and tau, the pathological functions of tau, and potential therapeutic strategies for an effective management of neuronal disorders., Competing Interests: Declaration of competing interest None., (Copyright © 2020 Elsevier B.V. All rights reserved.)

In mammalian small intestine, glucose is primarily absorbed via Na-dependent glucose co-transporter (SGLT1) on the brush border membrane (BBM) of absorptive villus cells. Malabsorption of nutrients (e.g., glucose) leads to malnutrition, a common symptom of inflammatory bowel disease (IBD), where the mucosa is characterized by chronic inflammation. Inducible nitric oxide (iNO) is known to be elevated in IBD mucosa. SAMP1/YitFc (SAMP1) mouse is a spontaneous model of chronic ileitis that develops lesions in its terminal ileum, very similar to human IBD. How SGLT1 may be affected in SAMP1 model of chronic ileitis is unknown. Ten-week-old SAMP1 mice with AKR mice as control were treated with N6-(1-iminoethyl)-L-lysine dihydrochloride (L-NIL) to inhibit iNO production. Intracellular NO levels were found to be increased in villus cells from SAMP1 mice. Moreover, SGLT1 and Na +/ K + -ATPase activities and BBM SGLT1 expression were significantly decreased. However, L-NIL treatment reduced the intracellular iNO production, and reversed both downregulated SGLT1 and Na + /K + -ATPase activities in SAMP1 mice. Inhibition of iNO by L-NIL treatment also significantly reversed the BBM SGLT1 protein expression in SAMP1 mice. L-NIL reversed the inflammation mediated downregulation of SGLT1 activity by restoring the BBM SGLT1 expression. Thus, regulation of SGLT1 in chronic ileitis is likely mediated by iNO.

The ineffective immunosuppressant's and targeted strategies to neutralize inflammatory mediators have worsened the scenario of heart failure and have opened many questions for debate. Stem cell therapy has proven to be a promising approach for treating heart following myocardial infarction (MI). Adult stem cells, induced pluripotent stem cells and embryonic stem cells are possible cell types and have successfully shown to regenerate damaged myocardial tissue in pre-clinical and clinical studies. Current implications of using mesenchymal stem cells (MSCs) owing to their immunomodulatory functions and paracrine effects could serve as an effective alternative treatment option for rejuvenating the heart post MI. The major setback associated with the use of MSCs is reduced cell retention, engraftment and decreased effectiveness. With a few reports on understanding the role of inflammation and its dual effects on the structure and function of heart, this review focuses on these missing insights and further exemplifies the role of MSCs as an alternative therapy in treating the pathological consequences in myocardial infarction (MI)., (Copyright © 2020 Elsevier Inc. All rights reserved.)

In obesity, increased absorption of dietary fat contributes to altered lipid homeostasis. In turn, dyslipidemia of obesity leads to many of the complications of obesity. Bile acids are necessary for the absorption of dietary fat. In the mammalian intestine, apical sodium-dependent bile acid cotransporter (ASBT; SLC10A2) is exclusively responsible for the reabsorption of bile acids in the terminal ileum. In rat and mice models of obesity and importantly in obese humans, ASBT was increased in ileal villus cells. The mechanism of stimulation of ASBT was secondary to an increase in ASBT expression in villus cell brush border membrane. The stimulation of ASBT was not secondary to the altered Na-extruding capacity of villus cells during obesity. Further, increased Farnesoid X receptor (FXR) expression in villus cells during obesity likely mediated the increase in ASBT. Moreover, enhanced FXR expression increased the expression of bile-acid-associated proteins (IBABP and OSTα) that are responsible for handling bile acids absorbed via ASBT in villus cells during obesity. Thus, this study demonstrated that in an epidemic condition, obesity, the dyslipidemia that leads to many of the complications of the condition, may, at least in part, be due to deregulation of intestinal bile acid absorption.

During obesity, diabetes and hypertension inevitably coexist and cause innumerable health disparities. In the obesity, diabetes, and hypertension triad (ODHT), deregulation of glucose and NaCl homeostasis, respectively, causes diabetes and hypertension. In the mammalian intestine, glucose is primarily absorbed by Na-glucose cotransport 1 (SGLT1) and coupled NaCl by the dual operation of Na-H exchange 3 (NHE3) and Cl-HCO 3 [down-regulated in adenoma (DRA) or putative anion transporter 1 (PAT1)] exchange in the brush border membrane (BBM) of villus cells. The basolateral membrane (BLM) Na/K-ATPase provides the favorable transcellular Na gradient for BBM SGLT1 and NHE3. How these multiple, distinct transport processes may be affected in ODHT is unclear. Here, we show the novel and broad regulation by Na/K-ATPase of glucose and NaCl absorption in ODHT in multiple species (mice, rats, and humans). In vivo , during obesity inhibition of villus-cell BLM, Na/K-ATPase led to compensatory stimulation of BBM SGLT1 and DRA or PAT1, whereas NHE3 was unaffected. Supporting this new cellular adaptive mechanism, direct silencing of BLM Na/K-ATPase in intestinal epithelial cells resulted in selective stimulation of BBM SGLT1 and DRA or PAT1 but not NHE3. These changes will lead to an increase in glucose absorption, maintenance of traditional coupled NaCl absorption, and a de novo increase in NaCl absorption from the novel coupling of stimulated SGLT1 with DRA or PAT1. Thus, these novel observations provide the pathophysiologic basis for the deregulation of glucose and NaCl homeostasis of diabetes and hypertension, respectively, during obesity. These observations may lead to more efficacious treatment for obesity-associated diabetes and hypertension.-Palaniappan, B., Arthur, S., Sundaram, V. L., Butts, M., Sundaram, S., Mani, K., Singh, S., Nepal, N., Sundaram, U. Inhibition of intestinal villus cell Na/K-ATPase mediates altered glucose and NaCl absorption in obesity-associated diabetes and hypertension.

In the mammalian small intestine, sodium is primarily absorbed by Na + /H + exchange (NHE3) and Na-glucose cotransport (SGLT1) in the brush border membrane (BBM) of villus cells. However, how enhanced cellular constitutive nitric oxide (cNO) may affect NHE3 and SGLT1 remains unclear. Both in vivo in rabbit intestinal villus cells and in vitro IEC-18 cells, administration of NO donor, GSNAP, modestly increased cNO. GSNAP stimulated SGLT1 in villus and IEC-18 cells. The mechanism of stimulation was secondary to an increase in the affinity of SGLT1 for glucose. The change in SGLT1 was not secondary to altered Na-extruding capacity of the cell since Na + /K + -ATPase was decreased by GSNAP treatment. In contrast, GSNAP inhibited NHE3 activity in villus cell BBM. The mechanism of NHE3 inhibition was secondary to reduced BBM transporter numbers. These studies demonstrated that the physiological increase in cNO uniquely regulates mammalian small intestinal NHE3 and SGLT1 to maintain Na homeostasis., (© 2019 The Authors. Physiological Reports published by Wiley Periodicals, Inc. on behalf of The Physiological Society and the American Physiological Society.)

Na-amino acid co-transporters (NaAAcT) are uniquely affected in rabbit intestinal villus cell brush border membrane (BBM) during chronic intestinal inflammation. Specifically, Na-alanine co-transport (ASCT1) is inhibited secondary to a reduction in the affinity of the co-transporter for alanine, whereas Na-glutamine co-transport (B0AT1) is inhibited secondary to a reduction in BBM co-transporter numbers. During chronic intestinal inflammation, there is abundant production of the potent oxidant peroxynitrite (OONO). However, whether OONO mediates the unique alteration in NaAAcT in intestinal epithelial cells during chronic intestinal inflammation is unknown. In this study, ASCT1 and B0AT1 were inhibited by OONO in vitro. The mechanism of inhibition of ASCT1 by OONO was secondary to a reduction in the affinity of the co-transporter for alanine, and secondary to a reduction in the number of co-transporters for B0AT1, which were further confirmed by Western blot analyses. In conclusion, peroxynitrite inhibited both BBM ASCT1 and B0AT1 in intestinal epithelial cells but by different mechanisms. These alterations in the villus cells are similar to those seen in the rabbit model of chronic enteritis. Therefore, this study indicates that peroxynitrite may mediate the inhibition of ASCT1 and B0AT1 during inflammation, when OONO levels are known to be elevated in the mucosa.

Pharmacological manipulations of constitutive nitric oxide (cNO) levels have been shown to have variable effects on Na absorption in vivo and in vitro in different tissues. Species differences, untoward in vivo effects (e.g. ENS, blood flow) and pharmacological non-specificity may account for these confounding observations. Thus, to directly and specifically determine the effect of cNO on brush border membrane Na/H exchange (NHE3) and Na-dependent glucose co-transport (SGLT-1), we inhibited cNO synthase (NOS3) with its siRNA in rat small intestinal epithelial cells (IEC-18) in vitro. As expected, intracellular cNO levels were reduced in siRNA NOS3 transfected cells. In these cells, SGLT-1 was significantly reduced compared to control. In contrast, NHE3 was significantly increased in siRNA NOS3 transfected cells. To determine if SGLT-1 changes were secondary to altered Na/K-ATPase, its activity was measured and found to be increased in NOS3 silenced cells. The mechanism of inhibition of SGLT-1 was secondary to diminished affinity of the co-transporter for glucose in NOS3 silenced cells. In contrast, the mechanism of stimulation of NHE3 is by increasing BBM exchanger numbers in siRNA NOS3 cells while the affinity was unaffected. Western blot studies of immunoreactive BBM proteins also confirmed the kinetic studies. All these data indicates that direct and specific inhibition of NOS3 with its siRNA inhibits SGLT-1 while stimulating NHE3 in the BBM. Thus, cNO uniquely and compensatorily regulates BBM NHE3 and SGLT-1 to maintain cellular Na homeostasis and these unique alterations by cNO are mediated by its intracellular 2nd messenger cGMP., (Copyright © 2018 Elsevier Inc. All rights reserved.)

This investigation provides generic information on the culturable corrosive and the microfouling bacterial community in a firewater distribution system that uses freshwater. Conventional microbiological methods were used for the selective isolation of the major microfouling bacteria. The isolates were characterized by 16S rRNA gene sequencing and the biofilm as well as the corrosion characteristics of the isolates were evaluated. Pseudomonas aeruginosa and Bacillus cereus were predominantly observed in all the samples analysed. Denaturing gradient gel electrophoresis (DGGE) was carried out for the various samples of firewater system (FWS) and the high intensity bands were sequenced to identify the predominant bacteria. Bacterial groups such as Cyanobacteria, Proteobacteria, Actinobacteria, Bacteroidetes and Firmicutes were identified. Biofilm thickness was recorded using confocal scanning laser microscopy (CSLM). This was the first study to report Lysinibacillus fusiformis in a firewater system and its role in iron corrosion. Sulphidogenic bacteria Tissierella sp. and Clostridium bifermentans generated sulphides in the range of 400-900 ppm. Significant corrosion rates of carbon steel (CS) coupons were observed up to 4.3 mpy. C. bifermentans induced more localized corrosion in CS with a pit diameter of 50 μm. Overall, the data on the characterization of the fouling bacteria, their biofilm forming potential and subsequent metal deterioration studies supported in designing an effective water treatment program., (Copyright © 2015 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.)

Na-K-ATPase, an integral membrane protein in mammalian cells, is responsible for maintaining the favorable intracellular Na gradient necessary to promote Na-coupled solute cotransport processes [e.g., Na-glucose cotransport (SGLT1)]. Inhibition of brush border membrane (BBM) SGLT1 is, at least in part, due to the diminished Na-K-ATPase in villus cells from chronically inflamed rabbit intestine. The aim of the present study was to determine the effect of Na-K-ATPase inhibition on the two major BBM Na absorptive pathways, specifically Na-glucose cotransport and Na/H exchange (NHE), in intestinal epithelial (IEC-18) cells. Na-K-ATPase was inhibited using 1 mM ouabain or siRNA for Na-K-ATPase-α1 in IEC-18 cells. SGLT1 activity was determined as 3-O-methyl-D-[(3)H]glucose uptake. Na-K-ATPase activity was measured as the amount of inorganic phosphate released. Treatment with ouabain resulted in SGLT1 inhibition at 1 h but stimulation at 24 h. To further characterize this unexpected stimulation of SGLT1, siRNA silencing was utilized to inhibit Na-K-ATPase-α1. SGLT1 activity was significantly upregulated by Na-K-ATPase silencing, while NHE3 activity remained unaltered. Kinetics showed that the mechanism of stimulation of SGLT1 activity was secondary to an increase in affinity of the cotransporter for glucose without a change in the number of cotransporters. Molecular studies demonstrated that the mechanism of stimulation was not secondary to altered BBM SGLT1 protein levels. Chronic and direct silencing of basolateral Na-K-ATPase uniquely regulates BBM Na absorptive pathways in intestinal epithelial cells. Specifically, while BBM NHE3 is unaffected, SGLT1 is stimulated secondary to enhanced affinity of the cotransporter., (Copyright © 2015 the American Physiological Society.)

Background: In the chronically inflamed rabbit small intestine, brush border membrane (BBM) Na-glutamine co-transport is inhibited in villus cells (mediated by B0AT1), while it is stimulated in crypt cells (mediated by SN2/SNAT5). How mast cells, known to be enhanced in the chronically inflamed intestine, may regulate B0AT1 in villus and SN2/SNAT5 in crypt cell is unknown. Thus, the aim of the present study is to determine the regulation of B0AT1 and SN2/SNAT5 by mast cells during chronic enteritis., Methods: Chronic intestinal inflammation was induced in male rabbits with intra-gastric inoculation of Eimeria magna oocytes. Rabbits with chronic inflammation were treated with ketotifen (10 mg/day) or saline (Placebo) for 2 days. Villus and crypts cells were isolated from the rabbit intestine using the Ca++ chelation technique. Na/K-ATPase activity was measured as Pi from cellular homogenate. BBM vesicles (BBMV) were prepared from villus and crypt cells and uptake studies were performed using rapid filtration technique with (3)H-Glutamine. Western blot analyses were done using B0AT1 and SN2 specific antibodies., Results: In villus cells, Na-glutamine co-transport inhibition observed during inflammation was completely reversed by ketotifen, a mast cell stabilizer. In contrast, in crypt cells, Na-glutamine co-transport stimulation was reversed to normal levels by ketotifen. Kinetic studies demonstrated that ketotifen reversed the inhibition of B0AT1 in villus cells by restoring co-transporter numbers in the BBM, whereas the stimulation of SN2/SNAT5 in crypts cells was reversed secondary to restoration of affinity of the co-transporter. Western blot analysis showed that ketotifen restored immune-reactive levels of B0AT1 in villus cells, while SN2/SNAT5 levels from crypts cell remained unchanged., Conclusion: In the present study we demonstrate that mast cells likely function as a common upstream immune pathway regulator of the Na-dependent glutamine co-transporters, B0AT1 in villus cells and SN2 in crypts cells that are uniquely altered in the chronically inflamed small intestine.