Starch bio-based composite active edible film functionalized with Carum carvi L. essential oil: antimicrobial, rheological, physic-mechanical and optical attributes.

In the present study, the antimicrobial, rheological, mechanical, barrier and optical properties of Carrageenan and Manihot esculenta (composite) starch biobased edible film incorporated with caraway (Carum carvi L.) essential oil (EO) were investigated. The Minimum Inhibitory Concentration (MIC) of caraway oil against B. cereus, E. coli, P. aeruginosa and S. aureus were found to be 0.6, 1.4, 1.4 and 0.8% respectively. The Gas Chromatography- Mass Spectroscopy (GC-MS) of caraway EO expressed a distinct chromatogram peak for phenolic compounds. Rheological results of Film-Forming Solution (FFS) revealed solid-like viscoelastic behavior. Incorporation of caraway EO in the film caused significant (P < 0.05) increase in moisture, moisture absorption, bio-degradability in terms of film solubility, L value, total color difference (ΔE), haziness and transparency value, however, significantly (P < 0.05) decreased tensile strength and whiteness index were observed. The zone of inhibition of caraway EO incorporated films against all test bacteria were highly significant (P < 0.01) than control whereas antibacterial activity was found more towards gram-positive bacteria than gram-negative bacteria. No significant (P>0.05) changes in thickness, density, water activity, swelling, elongation at break, water vapor transmission rate, a and b value were observed with increasing caraway EO concentration. These results with some good rheological, physic-mechanical, antimicrobial and optical characteristics suggest the application of such active film into a variety of foods with improved food safety and quality. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s13197-021-05028-1.

Thymoquinone supplementation ameliorates cisplatin-induced hepatic pathophysiology.

Hepatotoxicity is a major dose-limiting side effect of CP chemotherapy besides nephrotoxicity and gastrointestinal dysfunction. TQ, a principal Nigella sativa seed oil constituent, has been shown to improve hepatic functions in various in vivo models of acute hepatic injury. In view of this, the present study aimed to evaluate the effect of TQ against CP-induced hepatotoxicity. Rats were divided into four experimental groups; control, CP, CP+TQ and TQ. Animals in CP+TQ and TQ groups were administered TQ (1.5 mg/kg bwt, orally), with or without a single hepatotoxic dose of CP (6 mg/kg bwt, i.p.) respectively, for 14 days before and four days following the CP treatment. CP induced an upsurge in serum ALT and AST activities, indicating liver injury, as also confirmed by the histopathological findings. CP caused significant alterations in the activities of membrane marker enzymes, carbohydrate metabolic enzymes, and the enzymatic and nonenzymatic components of the antioxidant defense system. TQ supplementation ameliorated all these adverse biochemical and histological changes in CP-treated rats. Thus, TQ may have excellent scope for clinical applications in combating CP-induced hepatic pathophysiology.

Towards an optimal treatment algorithm for metastatic pancreatic ductal adenocarcinoma (PDA).

Chemotherapy remains the mainstay of treatment for advanced pancreatic ductal adenocarcinoma (pda). Two randomized trials have demonstrated superiority of the combination regimens folfirinox (5-fluorouracil, leucovorin, oxaliplatin, and irinotecan) and gemcitabine plus nab-paclitaxel over gemcitabine monotherapy as a first-line treatment in adequately fit subjects. Selected pda patients progressing to first-line therapy can receive secondline treatment with moderate clinical benefit. Nevertheless, the optimal algorithm and the role of combination therapy in second-line are still unclear. Published second-line pda clinical trials enrolled patients progressing to gemcitabine-based therapies in use before the approval of nab-paclitaxel and folfirinox. The evolving scenario in second-line may affect the choice of the first-line treatment. For example, nanoliposomal irinotecan plus 5-fluouracil and leucovorin is a novel second-line option which will be suitable only for patients progressing to gemcitabine-based therapy. Therefore, clinical judgement and appropriate patient selection remain key elements in treatment decision. In this review, we aim to illustrate currently available options and define a possible algorithm to guide treatment choice. Future clinical trials taking into account sequential treatment as a new paradigm in pda will help define a standard algorithm.

Degradation of serine-containing oligopeptides by Peptostreptococcus micros ATCC 33270.

BACKGROUND/AIMS: Microorganisms of Peptostreptococcus micros are asaccharolytic, anaerobic gram-positive cocci that are frequently isolated from human oral sites such as periodontal pockets. Preliminary study showed that several amino acids, including serine, enhanced slightly the growth of P. micros. Therefore, we investigated the degradation of serine and serine-containing oligopeptides. METHODS: Metabolic end products were determined with high-performance liquid chromatography. The related enzymatic activities in cell-free extract were also assayed. RESULTS: Washed P. micros degraded serine-tripeptides (Ser-Ser-Ser), and produced formate, pyruvate, acetate, and ammonia. They also degraded serinyl-tyrosine (Ser-Tyr) to the same products. Related enzymatic activities, such as serine dehydratase, pyruvate formate-lyase, formate dehydrogenase, pyruvate oxidoreductase, phosphate acetyltransferase, and acetate kinase, were detected in the cell-free extract, indicating that the organisms produced ATP in the serine metabolism. CONCLUSION: P. micros utilized serine-containing oligopeptides as exogenous metabolic substrates rather than serine itself, and degraded Ser-Ser-Ser and Ser-Tyr to formate, pyruvate, acetate, and ammonia with ATP generation.

A review of methods currently used for assessment of in vivo endothelial function.

An intact vascular endothelium is critical to the maintenance of normal arterial tone and coagulation status. Endothelial injury leading to dysfunction is thought to be a precursor to most if not all vascular disease, and has been implicated as a critical event in atherosclerosis. At present there are several methods available for detection of in vivo endothelial function, and the aim of this study was to critically review these methods. Five distinct methods were identified and studied in detail. These methods are diverse and each assesses a different vascular bed. Importantly there is no uniformity among investigators over choice of method and protocol, making it difficult to compare in vivo enothelial dysfunction between groups. These issues need to be addressed in large scale comparative analyses so that investigators can agree a common approach to endothelial function assessment.

The management of gastric outlet obstruction secondary to inoperable cancer.

BACKGROUND: Historically, the distressing symptoms of malignant gastric outlet obstruction have been best managed by open gastrojejunostomy. We provide an assessment of an alternative laparoscopic technique. METHODS: We reviewed eight patients undergoing laparoscopic gastrojejunostomy. Patient data included age, sex, operation time, morbidity and mortality, length of stay, and outcome at 6 months where possible. RESULTS: There were six men and two women, their median age was 67 years. Median operating time was 135 min, median time to solid food was 4 days, and median postoperative stay was 7 days. Seven of our eight patients were palliated successfully using this technique. CONCLUSION: The risks inherent in operating on these patients, who are by definition in a poor state of health, has encouraged much interest in minimal access surgery. We conclude that laparoscopic gastrojejunostomy provides effective palliation of gastric outlet obstruction, and we recommend further evaluation of this technique.

Amylin-insulin relationships in insulin resistance with and without diabetic hyperglycemia.

To determine if increased secretion of amylin can be implicated in the pathogenesis of non-insulin-dependent diabetes mellitus (NIDDM) in vitro and in vivo, we studied its relationships to insulin in insulin-resistant rats with and without NIDDM. In obesity-associated and dexamethasone-induced insulin resistance without diabetes, basal and stimulated secretion of amylin and insulin by isolated pancreata were proportionately elevated, leaving the amylin-to-insulin ratio (A/I) unchanged. By contrast, whenever diabetes occurred in dexamethasone-treated rats or in spontaneously diabetic obese insulin-resistant ZDF-drt male rats, a doubling of A/I was invariably observed due to an increase in amylin without a proportional increase in insulin secretion. Correction of dexamethasone-induced hyperglycemia with the glucocorticord receptor antagonist RU-486 was accompanied by a decline in A/I. Longitudinal in vivo studies demonstrated in both spontaneous and dexamethasone-induced models of NIDDM an increase in plasma A/I at the onset of hyperglycemia. In dexamethasone-induced diabetes, the increased A/I was associated with a high proamylin mRNA relative to proinsulin mRNA. We conclude that amylin and insulin expression and secretion rise in concert in compensated insulin-resistant states, but when hyperglycemia is present the increase in amylin exceeds that of insulin. Although a role of an increased A/I in the pathogenesis of NIDDM has not been established directly, these studies indicate that such a role could be possible.

trans-activation of the alpha 1-acid glycoprotein gene acute phase responsive element by multiple isoforms of C/EBP and glucocorticoid receptor.

alpha 1-Acid glycoprotein (AGP) is a major acute phase protein synthesized primarily by the liver. The AGP gene is transcriptionally activated in hepatocytes during the acute phase response to bacterial lipopolysaccharide. In this study, we analyzed an acute phase responsive element (APRE) located between nucleotide residues -127 to -104 relative to the transcription initiation site of the mouse AGP gene. Binding studies show that several trans-acting factors interact with the APRE. Using monospecific antibodies we demonstrate that three isoforms of the CCAAT/enhancer-binding protein (C/EBP) family, namely C/EBP alpha, C/EBP beta, and C/EBP delta, bind to the APRE. Furthermore, with liver nuclear protein from control animals, C/EPB alpha is the predominant form that binds to the APRE, whereas with nuclear proteins from acute phase-induced animals, C/EBP alpha is replaced by C/EBP beta. The mechanism of activation of the AGP gene during the acute phase response appears to involve an exchange of C/EBP alpha by C/EBP beta. C/EBP delta does not play a role in this reaction. Interestingly, the C/EBP binding site of the APRE partially overlaps a functional glucocorticoid responsive element. We present evidence that both purified C/EBP alpha and glucocorticoid receptor bind strongly to the APRE. By site-specific mutation, we have identified the C/EBP and glucocorticoid receptor binding sites in the APRE. These mutants were used in expression vectors to demonstrate that both C/EBP and glucocorticoid receptor are essential for maximal response to interleukin-6 and dexamethasone. These results demonstrate that the APRE is a composite binding site for multiple factors that are responsible for the transcriptional control of the mouse AGP. Finally, functional analyses indicate that C/EBP alpha, C/EBP beta, and C/EBP delta are strong transcriptional trans-activators of the AGP APRE in hepatoma cells. These data suggest that the regulatory activity of the C/EBP with the APRE in the liver may require interactions with adjacent proteins.

Adenovirus-mediated transfer of the muscle glycogen phosphorylase gene into hepatocytes confers altered regulation of glycogen metabolism.

The muscle isozyme of glycogen phosphorylase is potently activated by the allosteric ligand AMP, whereas the liver isozyme is not. In this study we have investigated the metabolic impact of expression of muscle phosphorylase in liver cells. To this end, we constructed a replication-defective, recombinant adenovirus containing the muscle glycogen phosphorylase cDNA (termed AdCMV-MGP) and used this system to infect hepatocytes in culture. AMP-activatable glycogen phosphorylase activity was increased 46-fold 6 days after infection of primary liver cells with AdCMV-MGP. Despite large increases in phosphorylase activity, glycogen levels were only slightly reduced in AdCMV-MGP-infected liver cells compared to uninfected cells or cells infected with wild-type adenovirus. The lack of correlation of phosphorylase activity and glycogen content suggests that the liver cell environment can inhibit the muscle phosphorylase isozyme. This inhibition can be overcome, however, by addition of carbonyl cyanide m-chlorophenylhydrazone (CCCP), which increases AMP levels by 30-fold and causes a much larger decrease in glycogen levels in AdCMV-MGP-infected cells than in uninfected or wild-type adenovirus-infected controls. CCCP treatment also caused a preferential decrease in glycogen content relative to glucagon treatment in AdCMV-MGP-infected hepatocytes (74% versus 11%, respectively), even though the two drugs caused equal increases in phosphorylase a activity. Introduction of muscle phosphorylase into hepatocytes therefore confers a capacity for glycogenolytic response to effectors that is not provided by the endogenous liver phosphorylase isozyme. The remarkable efficiency of adenovirus-mediated gene transfer into primary hepatocytes and the demonstration of altered regulation of glycogen metabolism as a consequence of expression of a non-cognate phosphorylase isozyme may have implications for gene therapy of glycogen storage diseases.

Posttranscriptional regulation of albumin and alpha-fetoprotein messenger RNA by transforming growth factor-beta 1 requires de novo RNA and protein synthesis.

Transforming growth factor-beta (TGF beta) has been implicated in the regulation of hepatocyte function. We have examined TGF beta 1 regulation of albumin and alpha-fetoprotein (AFP) mRNA levels in a well differentiated mouse hepatoma cell line (BWTG3). TGF beta 1 reversibly decreased steady state mRNA levels of both albumin and AFP. By nuclear run-on assays, we found that TGF beta 1 caused no significant change in transcription rates for albumin or AFP. Pretreatment with actinomycin-D prevented the TGF beta 1-induced decrease in albumin and AFP mRNA levels. Also, if cells were treated with actinomycin-D after a 12-h exposure to TGF beta 1, actinomycin-D abrogated the further decrease in albumin and AFP mRNA levels that occurred after treatment with TGF beta 1 alone. Cycloheximide pretreatment blocked the TGF beta 1-induced decrease in albumin and AFP mRNA levels. TGF beta 1 altered neither the rate of BWTG3 cell growth nor the levels of mRNA for the growth-associated protooncogene c-myc. These data suggest that TGF beta 1 has regulatory effects on specific hepatocyte functions that are independent of growth regulatory effects. The decrease in albumin and AFP mRNAs caused by TGF beta 1 is posttranscriptional and dependent upon de novo RNA and protein synthesis.

Coordinate regulation of amylin and insulin expression in response to hypoglycemia and fasting.

Amylin is a 37-amino acid peptide synthesized in the pancreatic beta-cell and cosecreted with insulin. In situ hybridization of nondiabetic rat pancreas shows that insulin and amylin RNA are both localized within the islet of Langerhans in a similar distribution. After 12 days of insulin-induced hypoglycemia (mean blood glucose 3.0 +/- 0.4 mM [54 +/- 8 mg/dl]), both insulin and amylin RNA fell greater than 95%. However, maintenance of euglycemia by simultaneous infusion of glucose with insulin did not suppress insulin or amylin RNA. Fasting suppressed amylin and insulin secretion from the isolated, perfused pancreas 70 and 58%, respectively, and with refeeding, secretion rates recovered to fed levels. Despite these changes in the rates of secretion, the relative ratio of amylin to insulin was not significantly different in fed, fasted, or refed rats. The molar ratio of insulin to amylin was estimated to be 100:2.3-2.6. Both insulin and amylin RNA was suppressed approximately 50% in response to fasting. Thus, although the absolute amounts of insulin and amylin change substantially under the conditions tested, the relative amounts of these peptides do not change.

Posttranscriptional regulation of neurotensin in the gut.

Previous studies have suggested an important role for neurotensin as an enterotrophic factor in the adaptive response of the gut. The purpose of this study was to determine the specific tissue distribution of neurotensin messenger RNA (mRNA) and to examine the molecular mechanisms that regulate intestinal neurotensin gene expression and content. In the first experiment, various segments of gut tissue from three Sprague-Dawley rats were harvested, and polyadenylated RNA was extracted for Northern hybridization with a rat neurotensin probe. In the second experiment, 32 Sprague-Dawley rats were fasted for 72 hours and then killed at 0, 3, 12, and 24 hours after refeeding (n = 8 rats/group). Rats fed ad libitum were killed before fasting (control, n = 8). Distal ileal segments (30 cm) were resected for measurement of neurotensin tissue concentration by radioimmunoassay and extraction of poly (A)+ RNA for Northern hybridization with a rat neurotensin complementary DNA probe. Blots were stripped and reprobed for beta-actin as a control for RNA loading. A nuclear run-on transcription assay was performed to determine the relative rate of neurotensin transcription. In the first experiment, neurotensin messenger RNA transcripts of 1.0 and 1.5 Kb sizes were found throughout the small intestine and proximal colon; the greatest abundance was found in the distal small intestine. In the second experiment, neurotensin tissue concentration was significantly reduced with fasting. Refeeding a diet for 24 hours returned neurotensin concentration to control levels. However, neither the amount of neurotensin messenger RNA nor its rate of transcription were altered by fasting and refeeding. These findings suggest that a posttranscriptional mechanism is responsible for regulation of neurotensin synthesis in gut mucosa.

Expression of reg/PSP, a pancreatic exocrine gene: relationship to changes in islet beta-cell mass.

A cDNA termed reg was recently isolated by differential screening of a library prepared from regenerating islets isolated from pancreatic remnants of rats subjected to 90% pancreatectomy and nicotinamide treatment. This led to speculation that this gene may be involved in expansion of beta-cell mass. In the current study we have measured reg expression after implantation and resection of a solid insulinoma tumor into rats, maneuvers known, respectively, to reduce and reexpand the volume of beta-cells in the islet. Animals with an implanted insulinoma tumor became profoundly hypoglycemic. Islet beta-cells declined from the normal 75% of total islet volume to less than 30%, in concert with a marked reduction in the reg mRNA level. Removal of the tumor resulted in a sharp increase in beta-cell replication, as measured by [3H]thymidine incorporation and a return to normal beta-cell volume within 4 days of tumor resection. This was associated with a transient induction in reg expression compared to that in tumor-bearing animals, effectively returning the amount of reg mRNA to the levels found in normal animals within 48 h; at later time points after tumor removal (3-7 days) reg expression declined, but then rose toward normal. In situ hybridization analysis localized the initial induction in reg mRNA expression to the exocrine pancreas. Continuous infusion of insulin into normal rats for 4 days, a maneuver that does not significantly reduce beta-cell mass, resulted in dramatically reduced insulin mRNA in islets, but no change in the levels of reg mRNA. We conclude that the diminution in pancreatic beta-cell mass caused by subcutaneous implantation of an insulinoma is associated with reduced reg gene expression and that the increase in beta-cell replication after resection of the tumor is preceded by return of reg gene expression toward normal.

Multifactorial resistance to adriamycin: relationship of DNA repair, glutathione transferase activity, drug efflux, and P-glycoprotein in cloned cell lines of adriamycin-sensitive and -resistant P388 leukemia.

Cloned lines of Adriamycin (ADR)-sensitive and -resistant P388 leukemia have been established, including P388/ADR/3 and P388/ADR/7 that are 5- and 10-fold more resistant than the cloned sensitive cell line P388/4 (Cancer Res., 46: 2978, 1986). A time course of ADR-induced DNA double-strand breaks revealed that in sensitive P388/4 cells, evidence of DNA repair was noted 4 h after removal of drug, whereas in resistant clone 3 and 7 cells repair was observed 1 h after drug removal. The earlier onset of DNA repair was statistically significant (p = 0.0154 for clone 3 cells, and p = 0.0009 for clone 7 cells). By contrast, once the repair process was initiated, the rate of repair was similar for all three cell lines. The level of glutathione transferase activity was determined in whole cell extracts. Enzyme activity (mean +/- SE) in sensitive cells was 9.49 +/- 1.00 nmol/min/mg protein, that in resistant clone 3 cells was 13.36 +/- 1.03 nmol/min/mg, and that in clone 7 cells was 13.96 +/- 1.44 nmol/min/mg; the 1.44-fold increase in enzyme activity in resistant cells was statistically significant (p = 0.01). Further evidence of induction of glutathione transferase was provided by Northern blot analysis using a 32P-labeled cDNA for an anionic glutathione transferase, which demonstrated approximately a twofold increase in mRNA in resistant clone 7 cells. Western blot analysis with a polyvalent antibody against anionic glutathione transferase also revealed a proportionate increase in gene product in resistant cells. Dose-survival studies showed that ADR-resistant cells were cross-resistant to actinomycin D, daunorubicin, mitoxantrone, colchicine, and etoposide, but not to the alkylating agent melphalan; this finding provided evidence that these cells are multidrug resistant. Using a cDNA probe for P-glycoprotein, a phenotypic marker for multidrug resistance, Northern blot analysis showed an increase in the steady state level of mRNA of approximately twofold in resistant clone 3 and 7 cells. Southern analysis with the same cDNA probe showed no evidence of gene amplification or rearrangement. Western blot analysis with monoclonal C219 antibody demonstrated a distinct increase in P-glycoprotein in resistant cells. Efflux of Adriamycin as measured by the efflux rate constant was identical in all three cell lines. Furthermore, the metabolic inhibitors azide and dinitrophenol did not augment drug uptake in either sensitive or resistant cells. These findings suggest that despite the increase in P-glycoprotein, an active extrusion pump was not operational in these cells.(ABSTRACT TRUNCATED AT 400 WORDS)