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Clinical Genetics Oct 2008Diabetes is a disease that could be treated more effectively with a better understanding of pancreas development. This review examines the role of master regulator genes... (Review)
Review
Diabetes is a disease that could be treated more effectively with a better understanding of pancreas development. This review examines the role of master regulator genes driving crucial steps in pancreas development, from foregut specification to differentiation of the five endocrine cell types. The roles of Pdx1, Ptf1a, and Ngn3 are particularly examined as they are both necessary and sufficient for promoting pancreatic cell fates (Pdx1, Ptf1a) and endocrine cell development (Ngn3). The roles of Arx and Pax4 are studied as they compose part of the regulatory mechanism balancing development of different types of endocrine cells within the iselts and promote the development of alpha/PP and beta/delta cell progenitors, respectively. The roles of the aforementioned genes, and the consequences of misexpression of them for functionality of the pancreas, are examined through recent studies in model organisms, particularly Xenopus and zebrafish. Recent developments in cell replacement therapy research are also covered, concentrating on stem cell research (coaxing both adult and embryonic stem cells toward a beta cell fate) and transdifferentiation (generating beta cells from other differentiated cell types).
Topics: Animals; Cell Differentiation; Diabetes Mellitus; Humans; Islets of Langerhans; Models, Biological; Pancreas; Transcription Factors
PubMed: 18783407
DOI: 10.1111/j.1399-0004.2008.01081.x -
Hepatobiliary & Pancreatic Diseases... Aug 2005Annular pancreas in adults is a rare embryologic abnormality detected after development of complications. Embryology, diagnosis and treatment strategies for symptomatic... (Review)
Review
BACKGROUND
Annular pancreas in adults is a rare embryologic abnormality detected after development of complications. Embryology, diagnosis and treatment strategies for symptomatic adult annular pancreas remain controversial. In this paper we reevaluated these problems in view of the technological and theoretical advances.
METHODS
In 2 patients with annular pancreas, one(36-year-old male patient) presenting with duodenal obstruction and duodenal ulcer associated with duodenocolic fistula underwent Billroth II gastrectomy and fistula ectomy and the other(17-year-old male patient) presenting with duodenal obstruction and duodenal ulcer underwent Billroth II gastrectomy. English language literature about annular pancreas etiology, diagnosis and treatment was reviewed.
RESULTS
Both of the patients had uneventfully recovered. Abdominal computed tomography, endoscopic retrograde cholangiopancreatography and magnetic resonance cholangiopancreatography showed typical images of annular pancreas. Duodenal bypass procedure, choledochojejunostomy, endoscopic sphincterotomy or biliary stenting, and pancreatic resection were alternative to treat this sort of anomaly.
CONCLUSIONS
Annular pancreas in adults is a rare congenital abnormality, while newer imaging modalities and an index of suspicion may assist in finding more cases. The management of this congenital anomaly should be individualized according to the associated complications.
Topics: Adolescent; Adult; Barium; Duodenal Obstruction; Humans; Male; Pancreas; Radiography, Abdominal; Tomography, X-Ray Computed
PubMed: 16109539
DOI: No ID Found -
Pancreas Mar 2006The hedgehog (Hh) family of genes, sonic hedgehog (Shh), Indian hedgehog (Ihh), and desert hedgehog (Dhh) encode signaling molecules that regulate multiple functions... (Review)
Review
The hedgehog (Hh) family of genes, sonic hedgehog (Shh), Indian hedgehog (Ihh), and desert hedgehog (Dhh) encode signaling molecules that regulate multiple functions during organ development and in adult tissues. Altered hedgehog signaling has been implicated in disturbed organ development as well as in different degenerative and neoplastic human diseases. Hedgehog signaling plays an important role in determination the fate of the mesoderm of the gut tube, as well as in early pancreatic development, and islet cell function. Recently, it has been shown that deregulation of hedgehog signaling molecules contributes to the pathogenesis and progression of pancreatic cancer and of chronic pancreatitis. Inhibition of hedgehog signaling using hedgehog antagonists reduces pancreatic cancer cell growth in vitro and in vivo, thus holding promise of novel agents in the treatment of this devastating disease. In this review, we discuss the role of hedgehog signaling during pancreatic development, its role in the pathogenesis of both chronic pancreatitis and pancreatic cancer, and lastly, the implications of this newly available information with regards to treatment of pancreatic cancer.
Topics: Animals; Hedgehog Proteins; Humans; Mice; Pancreas; Pancreatic Diseases; Pancreatic Neoplasms; Reference Values; Signal Transduction; Trans-Activators
PubMed: 16552330
DOI: 10.1097/01.mpa.0000202937.55460.0c -
The American Journal of Physiology May 1989The exocrine pancreas is generally considered to be a homogeneous organ at the morphological and functional levels. Recent work, reviewed here, has provided multiple... (Review)
Review
The exocrine pancreas is generally considered to be a homogeneous organ at the morphological and functional levels. Recent work, reviewed here, has provided multiple reasons to question this. Morphologically, differences have been found in cell size and digestive enzyme content in "peri-" vs. "teleinsular" acini by methods including acinar separation, enzyme assay, and both light and electron microscopic immunocytochemistry. Detection of several blood group antigens in human acinar tissue showed striking cellular heterogeneity in a mosaic pattern. Stimulation of pancreatic lobules by specific secretagogues and separation of individual zymogen granules with microfluorometric assay of enzyme content also confirmed heterogeneity at the lobular and organellar level. Functionally, evidence that nonparallel digestive enzyme secretion can be taken as direct support for acinar heterogeneity is reviewed, as is the work leading to direct demonstration of secretagogue-specific heterogeneous sequestration and storage of nascent digestive enzyme protein. A general overview of pancreatic acinar cell specificity is presented; the model incorporates temporal changes in secretion from eligible acini, with secretagogue specificity of whole acini containing specific preset mixtures of digestive enzymes.
Topics: Animals; Humans; Pancreas; Proteins
PubMed: 2655473
DOI: 10.1152/ajpgi.1989.256.5.G817 -
The Journal of Histochemistry and... Sep 2005Traditional histological descriptions of the pancreas distinguish between the exocrine and the endocrine pancreas, as if they were two functionally distinct glands. This... (Review)
Review
Traditional histological descriptions of the pancreas distinguish between the exocrine and the endocrine pancreas, as if they were two functionally distinct glands. This view has been proven incorrect and can be considered obsolete. Interactions between acinar and islet tissues have been well established through numerous studies that reveal the existence of anatomical and functional relationships between these compartments of the gland. Less attention, however, has traditionally been paid to the relationships occurring between the endocrine pancreas and the ductal system. Associations between islet tissue and ducts are considered by most researchers as only a transient epiphenomenon of endocrine development. This article reviews the evidence that has emerged in the last 10 years demonstrating the existence of stable, close, and systematic relationships between these two pancreatic compartments. Functional and pathophysiological implications are considered, and the existence of an "acinar-duct-islet" axis is put forward. The pancreas appears at present to be an integrated organ composed of three functionally related components of well-orchestrated endocrine and exocrine physiological responses.
Topics: Animals; Humans; Islets of Langerhans; Pancreas, Exocrine; Pancreatic Ducts; Pancreatic Hormones
PubMed: 15956021
DOI: 10.1369/jhc.5R6640.2005 -
Gastroenterology Jan 1979
Review
Topics: Animals; Diabetes Mellitus, Experimental; Histology, Comparative; Humans; Islets of Langerhans; Pancreas
PubMed: 361494
DOI: No ID Found -
Nutrition Reviews Apr 1969
Review
Topics: Child; Child, Preschool; Humans; Infant; Kwashiorkor; Pancreas; Pancreatic Diseases
PubMed: 4895878
DOI: No ID Found -
AJR. American Journal of Roentgenology Dec 2006The purpose of this article is to highlight the imaging features of congenital anomalies and normal variants of the pancreatic duct and the pancreas using contemporary... (Review)
Review
OBJECTIVE
The purpose of this article is to highlight the imaging features of congenital anomalies and normal variants of the pancreatic duct and the pancreas using contemporary imaging techniques such as MR cholangiopancreatography (MRCP), MRI, and helical CT.
CONCLUSION
Congenital anomalies and normal variants of the pancreatic duct and the pancreas may be clinically significant and may create a diagnostic challenge. Recognition of the updated imaging features of these entities is important in clinical management and for avoiding misdiagnosis.
Topics: Adult; Cholangiopancreatography, Magnetic Resonance; Choristoma; Female; Humans; Magnetic Resonance Imaging; Male; Middle Aged; Pancreas; Pancreatic Ducts; Reference Values; Tomography, Spiral Computed
PubMed: 17114549
DOI: 10.2214/AJR.05.0774 -
Ultrasound in Medicine & Biology Mar 2020Pulsed focused ultrasound (pFUS) utilizes short cycles of sound waves to mechanically shake cells within tissues which, in turn, causes transient local increases in...
Pulsed focused ultrasound (pFUS) utilizes short cycles of sound waves to mechanically shake cells within tissues which, in turn, causes transient local increases in cytokines, growth factors and cell adhesion molecules. Although the effect of pFUS has been investigated in several different organs including the kidney, muscle and heart, its effect on the pancreas has not been investigated. In the present work, we applied pFUS to the rodent pancreas with the following parameters: 1.1-MHz frequency, 5-Hz pulse repetition frequency, 5% duty cycle, 10-ms pulse length, 160-s duration. Low-intensity pFUS had a spatial average temporal average intensity of 11.5 W/cm and a negative peak pressure of 3 MPa; high-intensity pFUS had a spatial average temporal average intensity of 18.5 W/cm and negative peak pressure of 4 MPa. Here we found that pFUS changed the expression of several cytokines while having no effect on the underlying tissue histology or health of pancreatic cells (as reflected by no significant change in plasma levels of amylase and lipase). Furthermore, we found that this effect on cytokine expression in the pancreas was acoustic intensity dependent; while pFUS at low intensities turned off the expression of several cytokines, at high intensities it had the opposite effect and turned on the expression of these cytokines. The ability to non-invasively manipulate the microenvironment of the pancreas using sound waves could have profound implications for priming and modulating this organ for the application of cellular therapies in the context of both regenerative medicine (i.e., diabetes and pancreatitis) and oncology (i.e., pancreatic cancer).
Topics: Animals; Female; Mice; Pancreas; Ultrasonic Waves
PubMed: 31882169
DOI: 10.1016/j.ultrasmedbio.2019.11.016 -
Obesity Facts 2022Ectopic fat deposition in the pancreas is involved in the pathogenesis of metabolic sequelae following an attack of pancreatitis. However, its relationship with the...
INTRODUCTION
Ectopic fat deposition in the pancreas is involved in the pathogenesis of metabolic sequelae following an attack of pancreatitis. However, its relationship with the exocrine pancreas has never been explored in this setting. The aim was to investigate the associations between intra-pancreatic fat deposition (IPFD), pancreas size, and pancreatic enzymes.
METHODS
This cross-sectional study recruited individuals with a history of acute pancreatitis and healthy controls. All participants underwent 3T magnetic resonance imaging, from which IPFD, total pancreas volume (TPV), and pancreas diameters (across the head, body, and tail) were measured independently by 2 raters in a blinded fashion. Circulating levels of pancreatic amylase, pancreatic lipase, and chymotrypsin were measured in a fasted state. A series of linear regression analyses was conducted, accounting for possible confounders.
RESULTS
A total of 108 individuals with pancreatitis and 60 healthy controls were studied. There was a statistically significant difference in IPFD (p < 0.001), but not in TPV (p = 0.389), between the groups. In the post-pancreatitis group, IPFD was significantly inversely associated with pancreas tail diameter (β = -0.736, p = 0.036 in the most adjusted model). In the control group, IPFD was significantly inversely associated with TPV (β = -3.557, p = 0.026 in the most adjusted model). Levels of pancreatic amylase were significantly directly associated with pancreas tail diameter in the post-pancreatitis group (β = 3.891, p = 0.042 in the most adjusted model), whereas levels of pancreatic lipase were significantly inversely associated with TPV in the control group (β = -10.533, p = 0.024 in the most adjusted model).
CONCLUSION
Increased IPFD in individuals after an attack of pancreatitis is associated with reduced pancreas tail diameter, which is in turn associated with reduced circulating levels of pancreatic amylase. The relationship between IPFD and the exocrine pancreas warrants further investigations.
Topics: Acute Disease; Cross-Sectional Studies; Humans; Magnetic Resonance Imaging; Pancreas; Pancreatitis
PubMed: 34753126
DOI: 10.1159/000519621