Enantioselective metabolism of chiral polychlorinated biphenyl 2,2',3,4,4',5',6-Heptachlorobiphenyl (CB183) by human and rat CYP2B subfamilies.

Chiral polychlorinated biphenyls (PCBs) have atropisomers that have different axial chiralities and exist as racemic mixtures. However, biochemical processes often result in the unequal accumulation of these atropisomers in organisms. This phenomenon leads to enantiospecific toxicity enhancement or reduction because either of the atropisomers mainly affects toxicity expression.

Differences in Enantioselective Hydroxylation of 2,2',3,6-Tetrachlorobiphenyl (CB45) and 2,2',3,4',6-Pentachlorobiphenyl (CB91) by Human and Rat CYP2B Subfamilies.

Although polychlorinated biphenyls (PCBs) were commercially banned half a century ago, contamination of the environment and organisms by PCBs is still observed. PCBs show high persistence and bioaccumulation, resulting in toxicity. Among PCBs, chiral PCBs with more than three chlorine atoms at the -position exhibit developmental and neurodevelopmental toxicity.

Hydroxylation and dechlorination of 3,3',4,4'-tetrachlorobiphenyl (CB77) by rat and human CYP1A1s and critical roles of amino acids composing their substrate-binding cavity.

Cytochrome P450 (CYP) monooxygenases play critical roles in determining the toxicity of polychlorinated biphenyls (PCBs) in mammals. Hydroxylation of PCBs by these enzymes leads to increased water solubility, promoting the elimination of PCBs from the body. The CYP1 family is mainly responsible for metabolizing PCBs that exhibit a dioxin-like toxicity.

[Effects of periostin on hepatocellular carcinoma cells invasion, metastasis and prognosis].

To investigate the prognostic relationship between the expression levels of periostin (POSTN) in hepatocellular carcinoma (HCC) tissues as well as its effect in invasion and metastasis. The expression levels of POSTN in liver cancer tissues were detected with real-time quantitative PCR (QPCR) and immunohistochemistry (IHC). Kaplan-Meier method and Log-rank test were used to analyze the relationship between POSTN expression level and postoperative prognosis in patients with liver cancer.

Molecular insights into the role of a distal F240A mutation that alters CYP1A1 activity towards persistent organic pollutants.

Background: Cytochromes P450 are major drug-metabolizing enzymes involved in the biotransformation of diverse xenobiotics and endogenous chemicals. Persistent organic pollutants (POPs) are toxic hydrophobic compounds that cause serious environmental problems because of their poor degradability. This calls for rational design of enzymes capable of catalyzing their biotransformation.

From the Cover: Structural Determinants of the Position of 2,3',4,4',5-Pentachlorobiphenyl (CB118) Hydroxylation by Mammalian Cytochrome P450 Monooxygenases.

Polychlorinated biphenyls (PCBs) accumulate in mammals via the food chain because of their characteristics such as slow degradation and high hydrophobicity. One of the 209 PCB congeners, 2,3',4,4',5-pentachlorobiphenyl (CB118), is abundantly found in the environment and in mammals. Understanding the metabolic fate of CB118 can provide important information toward evaluating its toxicity.

A magnetosome-associated cytochrome MamP is critical for magnetite crystal growth during the exponential growth phase.

Magnetotactic bacteria use a specific set of conserved proteins to biomineralize crystals of magnetite or greigite within their cells in organelles called magnetosomes. Using Magnetospirillum magneticum AMB-1, we examined one of the magnetotactic bacteria-specific conserved proteins named MamP that was recently reported as a new type of cytochrome c that has iron oxidase activity. We found that MamP is a membrane-bound cytochrome, and the MamP content increases during the exponential growth phase compared to two other magnetosome-associated proteins on the same operon, MamA and MamK.

[Monitoring patients with chronic hepatitis during and after therapy].

Chronic viral hepatitis C and B are one of the major public health and medical problems. Both viruses cause life threatening liver diseases, i.e.

[Viral hepatitis. Croatian consensus conference--2009].

Summarized text of Croatian Consensus Conference on Viral Hepatitis of 2009 comprises the following chapters: 1) Epidemiology, 2) Clinical Picture, 3) Diagnostic Procedure, 4) Aims of Treatment of Viral Hepatitis, 5) Terminology, 6) Medicaments (6.1. Interferon, 6.

Impact of pentadecapeptide BPC 157 on muscle healing impaired by systemic corticosteroid application.

Background: The effect of systemic and local peptide treatment effective in muscle contusion and then on counteraction of corticosteroid-induced impairment was tested. The pentadecapeptide BPC 157, given without a carrier, improved the healing of transected quadriceps muscle. It also improved muscle healing in rats with muscle crush injury when applied systemically or locally.

Gastric pentadecapeptide BPC 157 as an effective therapy for muscle crush injury in the rat.

Purpose: Stable gastric pentadecapeptide BPC 157 accelerates the healing of a transected Achilles tendon and a transected quadriceps muscle. It may also be of clinical relevance as a systemic and local peptide treatment for crush injury of a major muscle, such as gastrocnemius muscle complex. BPC 157 is effective without a carrier, and it is presently undergoing trials for inflammatory bowel disease, and no toxicity has so far been reported.

Therapy for unhealed gastrocutaneous fistulas in rats as a model for analogous healing of persistent skin wounds and persistent gastric ulcers: stable gastric pentadecapeptide BPC 157, atropine, ranitidine, and omeprazole.

Objective: This study focused on unhealed gastrocutaneous fistulas to resolve whether standard drugs that promote healing of gastric ulcers may simultaneously have the same effect on cutaneous wounds, and corticosteroid aggravation, and to demonstrate why peptides such as BPC 157 exhibit a greater healing effect. Therefore, with the fistulas therapy, we challenge the wound/growth factors theory of the analogous nonhealing of wounds and persistent gastric ulcers.

Methods: The healing rate of gastrocutaneous fistula in rat (2-mm-diameter stomach defect, 3-mm-diameter skin defect) validates macro/microscopically and biomechanically a direct skin wound/stomach ulcer relation, and identifies a potential therapy consisting of: (i) stable gastric pentadecapeptide BPC 157 [in drinking water (10 microg/kg) (12 ml/rat/day) or intraperitoneally (10 microg/kg, 10 ng/kg, 10 pg/kg)], (ii) atropine (10 mg/kg), ranitidine (50 mg/kg), and omeprazole (50 mg/kg), (iii) 6-alpha-methylprednisolone (1 mg/kg) [intraperitoneally, once daily, first application at 30 min following surgery; last 24 h before sacrifice (at postoperative days 1, 2, 3, 7, 14, and 21)].

Prolonged esophagitis after primary dysfunction of the pyloric sphincter in the rat and therapeutic potential of the gastric pentadecapeptide BPC 157.

Seven or fourteen days or twelve months after suturing one tube into the pyloric sphincter (removed by peristalsis by the seventh day), rats exhibit prolonged esophagitis with a constantly lowered pressure not only in the pyloric, but also in the lower esophageal sphincter and a failure of both sphincters. Throughout the esophagitis experiment, gastric pentadecapeptide BPC 157 (PL 14736) is given intraperitoneally once a day (10 microg/kg, 10 ng/kg, last application 24 h before assessment), or continuously in drinking water at 0.16 microg/ml, 0.

Stable gastric pentadecapeptide BPC 157 in trials for inflammatory bowel disease (PL-10, PLD-116, PL 14736, Pliva, Croatia). Full and distended stomach, and vascular response.

Gastric pentadecapeptide BPC 157 (GEPPPGKPADDAGLV, M.W. 1419, safe in clinical trials for inflammatory bowel disease (PL 10, PLD 116, PLD 14736, Pliva, Croatia)) has a particular cytoprotective/adaptive cytoprotective activity.

An experimental model of prolonged esophagitis with sphincter failure in the rat and the therapeutic potential of gastric pentadecapeptide BPC 157.

We report a simple novel rat model that combines prolonged esophagitis and parallel sphincters failure. The anti-ulcer gastric pentadecapeptide BPC 157, which was found to be stable in gastric juice, and is being evaluated in inflammatory bowel disease trials, is an anti-esophagitis therapy that recovers failed sphincters. Twelve or twenty months after the initial challenge (tubes sutured into sphincters for one week and then spontaneously removed by peristalsis), rats exhibit prolonged esophagitis (confluent hemorrhagic and yellowish lesions, thinner epithelium and superficial corneal layer, with stratification derangement); constantly lowered pressure of both sphincters (assessed by using a water manometer connected to the drainage port of a Foley catheter implanted into the stomach either through esophageal or duodenal incision); and both lower esophageal and pyloric sphincter failure.

The presentation and organization of adaptive cytoprotection in the rat stomach, duodenum, and colon. Dedicated to André Robert the founder of the concept of cytoprotection and adaptive cytoprotection.

Background: Adaptive cytoprotection could be demonstrated in lesion attenuation within the whole gastrointestinal tract, in particular sequences, with onset and duration longer than the initial short-lasting period (i.e. one hour) defined by Robert in the stomach only.

[Factors influencing clinical course of viral hepatitis].

Hepatitis B and C are diseases characterized by a high global prevalence, complex clinical course and limited efficacy of currently available antiviral therapy. Hepatitis B: local factors have a significant influence not only on the disease prevalence but also on the disease course. Vertical transmission of the infection in the areas of high prevalence results in perinatal infection, which universaly leads to the development of chronic disease.

[Viral hepatitis: Croatian consensus statement].

There has been a dramatic improvement in diagnostic procedures and therapy of viral hepatitis in the last 20 years. Improvements in therapy caused an increase in actual cost, however, with significant long-term savings through a decreased cost of treatment of advanced liver disease including liver transplantation. The Croatian National Board for Viral Hepatitis has decided to initiate the organization of consensus conference on viral hepatitis enabling the leading experts in the country to give the best possible recommendations for the diagnosis, prophylaxis and therapy in our circumstances.