Publications by authors named "Munir Zaman"

Ovarian cancer (OvCa), while accounting for only 3% of all women's cancer, is the fifth leading cause of cancer death among women. One of the most significant obstacles to successful OvCa treatment is chemoresistance. The current lack of understanding of the driving mechanisms underlying chemoresistance hinders the development of effective therapeutics against this obstacle.

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Infants with short bowel syndrome (SBS) are at high risk for malabsorption, malnutrition, and failure to thrive. The objective of this study was to evaluate in a porcine model of SBS, the systemic absorption of a novel enteral Docosahexaenoic acid (DHA) formulation that forms micelles independent of bile salts (DHA-ALT®). We hypothesized that enteral delivery of DHA-ALT® would result in higher blood levels of DHA compared to a control DHA preparation due to improved intestinal absorption.

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Objectives: Nasal potential difference (NPD) measurement is part of the diagnostic criteria for cystic fibrosis (CF) and now used routinely as an endpoint in clinical trials of correcting the basic defect in CF. Intestinal current measurement (ICM), measured ex vivo on a rectal biopsy, has been used to study cystic fibrosis transmembrane conductance regulator (CFTR) function but has not been compared to NPD in the same subject in adults and children. The aim of the study is to evaluate the potential usefulness of ICM as a marker of CFTR function for treatment studies compared NPD in patients with CF and in healthy control subjects.

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Objectives: The aim of the present study was to quantify absorption coefficients of specific fatty acids in preterm infants as a function of diet, formula or breast milk (BM), and postnatal age; to identify the fatty acid structural characteristics that determine optimal fatty acid absorption.

Methods: Fatty acids from dietary and fecal samples were extracted and quantified by gas chromatography-mass spectroscopy. Fatty acid absorption coefficients (FA-CFAs) were calculated by comparing the total amount of fatty acids supplied by the diet to the amount quantified in the total fecal output during a 3-day period.

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Background: Morbidities of impaired immunity and dysregulated inflammation are common in preterm infants. Postnatal Intestinal development plays a critical role in the maturation of the immune system and is, in part, driven by exposure to an enteral diet.

Objective: The aim of this study was to evaluate the influence of the timing of the first enteral feeding on intestinal inflammation and risk of disease.

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Background: The critical fatty acids Docosahexaenoic Acid (DHA) and Arachidonic Acid (AA) decline in preterm infants within the first postnatal week and are associated with neonatal morbidities, including bronchopulmonary dysplasia (BPD). DHA and AA are precursors to downstream metabolites that terminate the inflammatory response. We hypothesized that treatment with Resolvin D1 and/or Lipoxin A4 would prevent lung injury in a murine model of BPD.

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Cystic fibrosis liver disease (CFLD) is a rapidly progressive biliary fibrosis, resembling primary sclerosing cholangitis that develops in 5-10% of patients with cystic fibrosis. Further research and evaluation of therapies are hampered by the lack of a mouse model for CFLD. Although primary sclerosing cholangitis is linked to both ulcerative colitis and loss of cystic fibrosis transmembrane conductance regulator (CFTR) ion channel function, induction of colitis with dextran sodium sulfate (DSS) in cftr(-/-) mice causes bile duct injury but no fibrosis.

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Objective: To measure the changes in whole blood fatty acid levels in premature infants and evaluate associations between these changes and neonatal morbidities.

Study Design: This was a retrospective cohort study of 88 infants born at <30 weeks' gestation. Serial fatty acid profiles during the first postnatal month and infant outcomes, including chronic lung disease (CLD), retinopathy of prematurity, and late-onset sepsis, were analyzed.

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Cystic fibrosis (CF) patients display a fatty acid imbalance characterized by low linoleic acid levels and variable changes in arachidonic acid. This led to the recommendation that CF patients consume a high-fat diet containing >6% linoleic acid. We hypothesized that increased conversion of linoleic acid to arachidonic acid in CF leads to increased levels of arachidonate-derived proinflammatory metabolites and that this process is exacerbated by increasing linoleic acid levels in the diet.

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Cystic fibrosis (CF) is associated with fatty acid alterations characterized by low linoleic and docosahexaenoic acid. It is not clear whether these fatty acid alterations are directly linked to cystic fibrosis transmembrane conductance regulator (CFTR) dysfunction or result from nutrient malabsorption. We hypothesized that if fatty acid alterations are a result of CFTR dysfunction, those alterations should be demonstrable in CF cell culture models.

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This article reports the development of an optical imaging technique, confocal light absorption and scattering spectroscopic (CLASS) microscopy, capable of noninvasively determining the dimensions and other physical properties of single subcellular organelles. CLASS microscopy combines the principles of light-scattering spectroscopy (LSS) with confocal microscopy. LSS is an optical technique that relates the spectroscopic properties of light elastically scattered by small particles to their size, refractive index, and shape.

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Background: Cystic fibrosis (CF) is characterized by an excessive inflammatory response in epithelial cells and macrophages. In CF mice, lung inflammation can be abrogated by oral treatment with docosahexaenoic acid (DHA). Since PPARs and LXRs are important regulators of inflammation and fatty acid metabolism in macrophages, we hypothesized that these pathways are dysregulated in CF macrophages and are corrected with DHA treatment.

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We have developed a novel optical method for observing submicrometer intracellular structures in living cells, which is called confocal light absorption and scattering spectroscopic (CLASS) microscopy. It combines confocal microscopy, a well-established high-resolution microscopic technique, with light-scattering spectroscopy. CLASS microscopy requires no exogenous labels and is capable of imaging and continuously monitoring individual viable cells, enabling the observation of cell and organelle functioning at scales of the order of 100 nm.

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We used a congenic C57Bl/6J cystic fibrosis transmembrane conductance regulator (Cftr)(-/-) mouse model, which develops cystic fibrosis (CF)-like pathology in all organs, to evaluate the short- and long-term therapeutic effects of dietary docosahexaenoic acid (DHA). Thirty-day-old Cftr(-/-) mice and wild-type littermates were randomized to receive a liquid diet with or without DHA (40 mg/day). Animals were killed for histological and lipid analysis after 7, 30, and 60 days of therapy.

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An association has been reported between alterations in fatty acid metabolism and cystic fibrosis (CF). We hypothesized that these alterations are specific for a particular lipid component(s) and are the result of a specific metabolic defect. The different lipid classes were examined for fatty acid changes by using pancreatic homogenates and primary cultures of pancreatic acini from cftr(-/-) (CF) and wild-type mice.

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Background: Primary sclerosing cholangitis (PSC) is associated with mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) gene. As proof of concept that CFTR dysfunction plays a role in PSC, induction of colitis in cftr mice results in bile duct injury that can be prevented by pretreatment with docosahexaenoic acid (DHA).

Objectives: Determine whether 1) CFTR dysfunction in cftr mice through a reduction in peroxisome proliferator activated receptor (PPAR)alpha or gamma leads to bile duct injury and 2) whether DHA prevents bile duct injury through an increase in PPAR.

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Background: Fatty acid ethyl esters (FAEE) are nonoxidative ethanol metabolites shown to produce toxic effects in the liver and pancreas in vivo and in vitro. Because alcohol-induced chronic pancreatitis is associated with mutations in the gene responsible for cystic fibrosis (CFTR), we hypothesized that CFTR dysfunction leads to increased levels of these toxic nonoxidative ethanol metabolites following alcohol administration.

Methods: Cystic fibrosis (CF) and wild-type (WT) mice were injected intraperitoneally with 1, 2, or 3 g/kg of 50% ethanol.

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Patients with cystic fibrosis (CF) exhibit an excessive host inflammatory response. The aim of this study was to determine (i) whether interleukin 8 (IL-8) secretion is increased from monocytes from subjects heterozygous as well as homozygous for cystic fibrosis transmembrane conductance regulator (CFTR) mutations and (ii) whether this is due to increased cell surface lipopolysaccharide (LPS) receptors or, alternatively, increased activation of mitogen-activated protein kinases (MAPK). The basal level of IL-8 secretion was higher from monocytes from CF patients than from monocytes from healthy controls (P = 0.

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Some of the pathological manifestations of cystic fibrosis are in accordance with an impaired expression and/or activity of PPARgamma. We hypothesized that PPARgamma expression is altered in tissues lacking the normal cystic fibrosis transmembrane regulator protein (CFTR). PPARgamma mRNA levels were measured in colonic mucosa, ileal mucosa, adipose tissue, lung, and liver from wild-type and cftr-/- mice by quantitative RT-PCR.

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It is unknown why some patients with inflammatory bowel disease develop primary sclerosing cholangitis. We have recently shown that patients with primary sclerosing cholangitis have an increased prevalence of mutations in the gene responsible for cystic fibrosis (CFTR) compared with individuals with inflammatory bowel disease alone. Our aim was to examine whether induction of colitis by oral dextran leads to bile duct injury in mice heterozygous or homozygous for mutations in CFTR.

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Background: Patients with cystic fibrosis have altered levels of plasma fatty acids. We previously demonstrated that arachidonic acid levels are increased and docosahexaenoic acid levels are decreased in affected tissues from cystic fibrosis-knockout mice. In this study we determined whether humans with mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) gene have a similar fatty acid defect in tissues expressing CFTR.

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The mechanism by which Pseudomonas causes excessive inflammation in the cystic fibrosis lung is unclear. We have reported that arachidonic acid is increased and docosahexaenoic acid (DHA) decreased in lung, pancreas, and ileum from cftr-/- mice. Oral DHA corrected this defect and reversed the pathology.

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