Simultaneous determination of lactulose, sucrose, sucralose, and mannitol using high-performance liquid chromatography-refractive index to estimate intestinal permeability in patients with active ulcerative colitis.

OBJECTIVES: The intestinal permeability (IP) of sugars and their derivatives has been widely used to assess mucosal damage in gastrointestinal diseases. Ulcerative colitis (UC) is a recurring and relapsing disease that causes inflammation of the gut. IP of sugars can be evaluated and correlated with the flare of UC. MATERIALS AND METHODS: A prospective study was conducted on 91 patients with active UC at the tertiary care center in North India. Mayo grading system assessed disease activity, and IP was assessed by measuring sucrose, lactulose, mannitol, and sucralose in urine samples from UC patients. A high-performance liquid chromatography (HPLC) method to detect all of these sugars simultaneously using a refractive index detector was developed and further validated in patients with UC. RESULTS: The analytical recovery rate of the tested sugars ranged from 95% to 146% in the urine matrix. The limit of detection and limit of quantification were 78.838 mg/L and 262.79 mg/L for sucrose, 84.994 mg/L and 283.31 mg/L for lactulose, 74.789 mg/L and 249.30 mg/L for mannitol, and 50.908 mg/L and 169.69 mg/L for sucralose. CONCLUSION: The standardized HPLC method is sensitive and suitable for the simultaneous detection and determination of different sugar moieties in the urine sample. Patients with UC can be evaluated indirectly for the flare by estimating the recovery rate of sugars through gut permeability. The procedure is noninvasive and thus improves the quality of life of chronically ill patients.

Neutrophil gelatinase-associated lipocalin: An early biomarker for predicting acute kidney injury and severity in patients with acute pancreatitis.

BACKGROUND AND AIM: Acute kidney injury (AKI) in severe acute pancreatitis (SAP) has a high mortality rate. Traditionally used serum creatinine is an insensitive biomarker for the early detection of AKI. We aimed to study the role of plasma and urinary neutrophil gelatinase-associated lipocalin (NGAL) in predicting AKI and a severe course in patients with acute pancreatitis (AP). METHODS: Consecutive patients of AP who presented within 72 h of symptom onset and age- and gender-matched healthy controls were included. Urinary and serum NGAL levels [enzyme-linked immunosorbent assay (ELISA)] were evaluated within 24 h of and 72 h after admission and once in controls. Urine and serum NGAL levels were correlated with development of AKI, severity, and outcomes of AP. RESULTS: Fifty patients with AP and 30 controls were enrolled. The mean serum and urine NGAL levels in patients on day 1 were significantly higher than the serum and urine NGAL levels in controls (P < 0.001). After excluding patients with AKI on day 1 (n = 10), both serum and urinary NGAL levels on days 1 and 3 were significantly higher in patients who subsequently developed AKI (n = 11) compared to those who did not (n = 29) (P = 0.02, 0.01 and P < 0.001, 0.03). A urinary NGAL level of 221.03 ng/mL on day 1 predicted AKI with a sensitivity and specificity of 82 and 80%, respectively (AUC = 0.9). Mean serum and urinary NGAL levels on day 1 were significantly elevated in patients with SAP compared to those without SAP (P = 0.04 and <0.001). CONCLUSION: NGAL levels in urine and serum can predict severity of AP and development of AKI.

Use of Bacteria in Cancer Therapy.

Cancer is one of the most dreaded diseases in humans and most common cause of death in twenty-first century. New cancer therapies are urgently required because of the existing pharmacological side effects of the conventional chemotherapy, radiation, or surgery. Newer modalities such as cancer vaccines and biological therapies are proving very helpful in the treatment of cancer along with the conventional therapies. The success of these novel cancer therapies is attributed to their lesser toxicity and the specific killing of the cancer cells. Bacterial therapy for cancer has been recognized a century ago. Live, attenuated, or genetically modified obligate or facultative anaerobic bacterial species exhibit the inherent property of colonizing the tumors and are capable of multiplying selectively inside the tumors, thereby inhibiting cancerous growths. The bacteria and their spores are used in the target specific therapies, delivering the prodrugs and the various proteins to the tumors. Albeit bacterial treatment of cancer is providing new perspective in the treatment of disease, the use of microorganisms to target tumors has certain confinements. The biosafety, genetic instability and the confounded interaction of the bacteria with treatment drugs, requires the more noteworthy consideration regarding the use of this novel treatment in the cancer treatment.

Status of colorectal cancer devices: present scenario.

PURPOSE: The purpose of this study was the colonoscopic detection and removal of neoplasia from the colorectum to prevent the development of colorectal cancer. METHOD: Various online medical databases were searched such as PubMed, ACS, NCI, NIH, WHO, etc. for relevant publications and clinical trials for new developments in colonoscopic devices that are intended for diagnostic visualization and therapeutic interventions of the digestive tract. RESULT: HD colon and I-Scan both has shown to increase the detection of sporadic adenomas with high quality. Third Eye Retroscope confers the backward view of colon, but aeroscope screens the entire colon in 30-60 min. Narrow-band imaging enhances mucosal and vascular details through the color differentiation of precancerous or cancerous polyp, compared to white light colonoscopy. The PillCam Colon Capsule is another new technique which is easily inserted and painless. In case of chemotherapy, Therasphere with Yttrium-90 has good results in the treatment of colorectal adenocarcinoma metastasis. Radiofrequency ablation is a good technique for tumors ablation and Staple Line Reinforcement prevents the leak during and post-surgery of colon. FOBT is much more sensitive and cheaper test for colorectal cancer screening. CONCLUSION: Registered clinical trials have shown promising results for neoplasia detection by I-Scan, TER, and NBI imaging techniques will change current colonoscopic practice in colorectal cancer screening. However, more studies and inventions are required for improving the patient safety and efficacy.

Current status of pharmacological treatment of colorectal cancer.

AIM: To review the clinical trials for the development in drugs for chemotherapeutic treatment of colorectal cancer (CRC). METHODS: A systematic review identified randomized controlled trials (RCTs) assessing drugs for the treatment of CRC or adenomatous polyps from www.clinicaltrials.gov. Various online medical databases were searched for relevant publications. RESULTS: Combination treatment regimens of standard drugs with newer agents have been shown to improve overall survival, disease-free survival, time to progression and quality of life compared to that with standard drugs alone in patients with advanced colorectal cancer. The FOLFOXIRI regimen has been associated with a significantly higher response rate, progression-free survival and overall survival compared to the FOLFIRI regimen. CONCLUSION: Oxaliplatin plus intravenous bolus fluorouracil and leucovorin has been shown to be superior for disease-free survival when compared to intravenous bolus fluorouracil and leucovorin. In addition, oxaliplatin regimens were more likely to result in successful surgical resections. First line treatment with cetuximab plus fluorouracil, leucovorin and irinotecan has been found to reduce the risk of metastatic progression in patients with epidermal growth factor receptor-positive colorectal cancer with unresectable metastases. The addition of bevacizumab has been shown to significantly increase overall and progression-free survival when given in combination with standard therapy.

Chemopreventive effect of different ratios of fish oil and corn oil on prognostic markers, DNA damage and cell cycle in colon carcinogenesis.

Fish oil (FO) rich in n-3 polyunsaturated fatty acids (PUFAs) have a protective role in autoimmune disorders, type 2 diabetes, rheumatoid arthritis, and cancer, whereas corn oil (CO) rich in n-6 PUFAs has a proinflammatory and procarcinogenic effect. A balanced n-3/n-6 PUFA ratio in diet rather than absolute intake of either may be responsible for decreasing cancer incidence. This study was designed to evaluate the chemopreventive effect of different ratios of FO and CO on prognostic markers, DNA damage, and cell cycle distribution in colon carcinogenesis. Male Wistar rats were divided into control, N,N'-dimethylhydrazine dihydrochloride (DMH) treated, FO+CO(1 : 1)+DMH, and FO+CO(2.5 : 1)+DMH. All the groups, except control, received a weekly injection of DMH for 4 weeks. The animals were given modified AIN-76A diets and killed either 48 h later (initiation phase) or kept for 16 weeks (postinitiation phase). The animals treated with DMH in both the phases showed an increase in multiple plaque lesions, total sialic acid, lipid associated sialic acid, DNA damage and cell proliferation. However, levels of p53 in the postinitiation and cyclin D1 in both the phases were significantly elevated. FO+CO(2.5 : 1)+DMH treatment in both the phases led to a decrease in multiple plaque lesions, DNA damage, total sialic acid, lipid associated sialic acid as compared with the DMH treated group. There was a G1 arrest with a decrease in p53 and cyclin D1 levels in FO+CO(2.5 : 1) in both the phases whereas treatment with FO+CO(1 : 1)+DMH led to same results in the postinitiation phase only. This study suggests that FO+CO(2.5 : 1) is more effective in chemoprevention of experimental colon carcinogenesis.

Evaluation of the role of oxidative stress in chemopreventive action of fish oil and celecoxib in the initiation phase of 7,12-dimethyl benz(α)anthracene-induced mammary carcinogenesis.

Cyclooxygenase-2 (COX-2) enzyme plays an important role in cancer development. COX-2 inhibition by non-steroidal anti-inflammatory drugs is a useful approach for cancer prevention, but its usage has been associated with side effects. n-3 polyunsaturated fatty acids also exhibit a chemopreventive effect mediated by COX-2 inhibition. Therefore, the present study was designed to evaluate the effect of combined dosage of celecoxib and fish oil in experimental mammary carcinogenesis. Female Wistar rats were distributed as control, 7,12-dimethyl benz(α)anthracene (DMBA) treated, celecoxib + fish oil (20 mg/kg b.w. + 0.5 ml), celecoxib + fish oil (30 mg/kg b.w. + 0.25 ml), and their corresponding controls treated with fish oil or celecoxib only. The treatment was given for 7 days, and on the 8th day animals of all the groups except the control group received DMBA orally and sacrificed after 90 days. The histopathology, DNA fragmentation, total sialic acid (TSA), lipid-associated sialic acid (LASA), and oxidative stress were measured in mammary tissue and liver mitochondrial fraction. The results showed ductal hyperplasia and an increase in TSA, LASA, lipid peroxidation, and nitrite levels with a decrease in the antioxidants on DMBA treatment. Pretreatment with celecoxib and fish oil in DMBA-treated animals led to normal histology, increase in DNA fragmentation, and decrease in TSA and LASA levels with reduced oxidative stress, and the effect was more pronounced than animals pretreated with either celecoxib/fish oil alone suggesting a synergistic effect of the two regimens. To conclude, a combination of celecoxib and fish oil is a better strategy for cancer chemoprevention than celecoxib/fish oil alone.

Chemopreventive effect of different ratios of fish oil and corn oil in experimental colon carcinogenesis.

n-3 Polyunsaturated fatty acids (PUFA) have a chemopreventive effect while n-6 PUFA promote carcinogenesis. The effect of these essential fatty acids may be related to oxidative stress. Therefore, the study was designed to evaluate the effect of different ratios of fish oil (FO) and corn oil (CO) in the prevention of colon cancer. Male Wistar rats were divided into control, dimethylhydrazine dihydrochloride (DMH) treated, FO + CO (1:1) and FO + CO (2.5:1). All the groups, except the control received a weekly injection of DMH for 4 weeks. The animals were sacrificed either 48 h later (initiation phase) or kept for 16 weeks (post initiation phase). DMH treatment in the initiation phase animals showed mild to moderate inflammation, decreased ROS and TrxR activity, increased antioxidants, apoptosis and ACF multiplicity. The post initiation study showed severe inflammation with hyperplasia, increased ACF multiplicity and ROS levels, a decrease in antioxidants and apoptosis. The FO + CO (1:1) treated animals showed severe inflammation, a decrease in ROS, an increase in antioxidants and apoptosis in the initiation phase. FO + CO (1:1) in the post initiation phase and FO + CO (2.5:1) in the initiation showed mild inflammation, increased ROS, apoptosis and decreased antioxidants. There was a decrease in ACF multiplicity and ROS levels, increased antioxidants and apoptosis in the post initiation phase study. The present study suggests that FO has a dose- and time-dependent chemopreventive effect in colon cancer mediated through oxidative stress and apoptosis.

Mechanism of action of celecoxib on normal and acid-challenged gastric mucosa.

Selective COX-2 inhibitor, celecoxib, delays the healing of gastric ulcers by inhibiting prostaglandins synthesis. Therefore, the effect of celecoxib on normal and acid-challenged gastric mucosa was studied. Wistar rats were distributed into four groups: group-1 (vehicle treated), group-2 (celecoxib treated), group-3 (given 0.6N HCl) and group-4 (HCl+celecoxib treated). The gastric mucosa was assessed histopathologically and by evaluating gastric adherent mucus. To assess the role of oxidative stress, the levels of free radicals and antioxidants were measured. The histopathological examination showed mild inflammation in group-2, moderate inflammation in group-3 and severe inflammation in group-4. The results showed an increase in malondialdehyde and a decrease in gastric adherent mucus, nitrite, reactive thiols and glutathione in groups-2-4 as compared to control group. Activity of superoxide dismutase, catalase and glutathione-s-transferase was increased in all the groups except the group-1. The present study suggested that celecoxib aggravated the gastric damage caused by acid which may be mediated by altering the balance between free radicals and antioxidants.

Role of oxidative stress in lansoprazole-mediated gastric and hepatic protection in Wistar rats.

BACKGROUND AND AIM: Lansoprazole, a benzimidazole derivative, is a widely-used proton-pump inhibitor. In addition, it has been reported to have an independent gastroprotective action. Since free radicals and antioxidant mechanisms appear to counter-act tissue-related injury, we studied the effect of lansoprazole on oxidative stress in acid-ethanol gastric injury. As this drug is metabolized in the liver, we also studied its effect on the liver. METHODS: Wistar rats were divided into three groups: control group, group I (vehicle treatment) and group II (lansoprazole treatment for eight days). In all the groups, injury was induced by ethanol-HCl administration. The effect of lansoprazole on free-radical generation and various antioxidants, e.g. superoxide dismutase (SOD), catalase, reduced glutathione (GSH), glutathione-s-transferase (GST) and glutathione reductase was evaluated in the gastric mucosal and liver homogenates. RESULTS: Ethanol-HCl administration initiated injury as shown by increase in malondialdehyde (MDA) levels in both gastric mucosa and liver. There was an increase in SOD and GST activity and a decrease in catalase, glutathione reductase and GSH in the gastric mucosa. In liver, ethanol-HCl administration decreased the activity of SOD, catalase and GSH and increased GST activity. Lansoprazole pretreatment led to decrease in the levels of MDA and increase in SOD, catalase, GSH, glutathione reductase and GST in both the gastric mucosa and liver. CONCLUSIONS: Lansoprazole has a protective action on gastric mucosa and the liver. This protection is mediated by a decrease in oxidative stress and a concomitant in-crease in antioxidants.

Role of oxidative stress in celecoxib-induced renal damage in wistar rats.

Celecoxib, a selective cyclo-oxygenase-2 (Cox-2) inhibitor, prevents the formation of prostaglandins, responsible for maintenance of renal function. Celecoxib administration may lead to renal damage. Since free radicals and antioxidant mechanisms play a significant role in renal injury; this study was designed to evaluate the role of oxidative stress in celecoxib-induced renal damage. The administration of celecoxib resulted in moderate and mild tubulointerstitial nephritis in chronic and acute group. The renal function tests were significantly altered only in the chronic group. The results in both the acute and the chronic group showed (1) a significant increase in the lipid peroxidation and in the activities of superoxide dismutase, catalase and glutathione-S-transferase and (2) a decrease in nitrite, reactive thiols and glutathione. In conclusion, our study suggests that chronic administration of celecoxib may have a damaging effect on kidney, as evident through altered histopathology and renal functions. This damage may be mediated by oxidative stress.