We aim to identify factors associated with invalid TE results in a tertiary referral center in a large prospective cohort study. Methods: Consecutive learn more patients who were referred for TE between September 2011 to March 2013 were included. Age, gender, body mass index (BMI) and waist circumference were recorded. An invalid result was defined as failure to capture 10 readings or interquartile range (IQR) of more than 30%. Patients were assessed with Fibroscan™

using a medium-sized (M) probe. Results: Among the 1919 cases referred, valid results were acquired in 1851 (96.5%). Univariate analysis showed that high waist circumference (p = 0.003) and high BMI (p = 0.001) were associated with invalid results. Advanced age and female gender were not statistically significant. In multivariate analysis which included age, gender, BMI, and waist circumference, BMI was shown to be the only independent predictor for invalid results (Table 1). The number of invalid TE studies increased with increasing BMI (5.2% in BMI > 25 vs 11.5% in BMI > 30 vs 26.1% in BMI > 35). Conclusion: Body mass index is independently associated with invalid results for transient elastography. Patients

with BMI > 35 should consider other modalities to assess liver fibrosis. Key Word(s): 1. elastography; 2. body mass index; 3. liver fibrosis; selleck 4. prospective study; Presenting Author: VISHAL SHARMA Additional Authors: SURINDERS RANA, DEEPAKK BHASIN, VINITA CHAUDHARY, RAVI SHARMA Corresponding Author: DEEPAKK BHASIN Affiliations: PGIMER Objective: Esophageal varices are a common cause of gastrointestinal bleed in portal hypertension. Duodenal varices (DV) although an uncommon cause, are an important cause because of the severe nature of the bleed

and associated adverse outcome. Methods: We retrospectively evaluated patients with DV seen at our institution over past 4 years. Their clinical, endoscopic and endoscopic ultrasound (EUS) features were analysed as was the treatment and its outcome. Results: Ten patients (9 males; mean age was 35.8 ± 7.68 years) with DV were studied. Five patients had underlying cirrhosis and five had DV see more because of non-cirrhotic portal hypertension (four patients had extrahepatic portal venous obstruction and one patient had non-cirrhotic portal fibrosis). Five patients presented with upper gastrointestinal bleed (GI) whereas in the remaining five patients DV were detected on endoscopy performed for evaluation of portal hypertension. Endoscopy revealed submucosal lesion in 9 patients whereas in one patient an initial endoscopic diagnosis of dieulafoy’s lesion was made. But EUS could clearly identify DV in all the patients.

Whether this recent categorization truly reflects the histogenesis of this unique neoplasm and the similarity of its biological behavior to cholangiocarcinoma

is an issue yet to be resolved. Although a rare cancer, combined HCC-CC is gaining recognition and histopathology Tyrosine Kinase Inhibitor Library nmr remains the gold standard for its diagnosis. The clinical outcome of combined HCC-CC may differ from HCC and CC and a specific treatment modality towards this unique cancer may be required. It has become clearer that hepatic progenitor cells are present in not only HCC23,25,44 and CC45 but also in combined HCC-CC.29–32 The role of hepatic progenitor cells as the cell of origin in combined HCC-CC is an interesting subject but it has been limited by the current lack of an animal model. Ongoing studies may elucidate the pathways for the development of novel targeted therapy. The author thanks Virginia Lore and Cynthia Long for their excellent assistance in preparing this manuscript. “
“Persistent infection with hepatitis C virus (HCV) is a major www.selleckchem.com/products/ch5424802.html risk toward development of hepatocellular carcinoma (HCC). The elucidation of pathogenesis of HCV-associated

liver disease is hampered by the absence of appropriate animal models: there has been no animal model for HCV infection/pathogenesis except for the chimpanzee. In contrast, a number of transgenic mouse lines carrying the cDNA of the HCV genome have been established and evaluated in the study of HCV pathogenesis. The studies using transgenic mouse models, in which the HCV proteins such as the core protein are expressed, indicate the direct pathogenicity of HCV, including oncogenic

activities. HCV transgenic mouse models also show a close relationship between HCV and some hepatic and extrahepatic manifestations selleck chemical such as hepatic steatosis, insulin resistance or Sjögren’s syndrome. A crucial role of hepatic steatosis and insulin resistance in the pathogenesis of liver disease in HCV infection has been demonstrated, implying hepatitis C to be a metabolic disease. Besides the data connecting liver fibrosis progression and the disturbance in lipid and glucose metabolisms in hepatitis C patients, a series of evidence was found showing the association between these two conditions and HCV infection, chiefly using transgenic mouse carrying the HCV genome. Furthermore, the persistent activation of peroxisome proliferator-activated receptor (PPAR)-α has recently been found, yielding dramatic changes in the lipid metabolism and oxidative stress overproduction in cooperation with the mitochondrial dysfunction. These results would provide a clue for further understanding of the role of lipid metabolism in pathogenesis of hepatitis C including liver injury and hepatocarcinogenesis. “
“Background and Aim:  The widespread use of screening programs has resulted in an increase in detection of small hepatocellular carcinoma (HCC).

6B and Supporting Fig. 6A), strengthening the idea that TGR5 may control ionic composition of bile after PH. In agreement with these data, biliary pH, although similar in WT and TGR5 KO mice before PH, was maintained or slightly increased in WT, but significantly fell in TGR5 KO mice after PH (Fig. 6C). Of note, the defect in ion secretion in bile observed in TGR5 KO mice after PH was not secondary to cholestasis, because BDL (at 48 hours) did not inhibit, but even increased slightly, bile

flow and ionic output in WT, but not in TGR5 KO, mice (Supporting Fig. 6B). Biliary BA concentrations and outputs were not significantly different in WT and TGR5 KO mice, both before and after PH, suggesting that bile flow deregulation in TGR5 KO mice did not result from a reduced BA flow rate (Supporting Fig. 6C). Together, these data strongly suggest that TGR5-mediated signals may control adaptive ion transport in bile under circumstances Paclitaxel order in which BA overload occurs, such as after PH and BDL. Although we did not find any

significant difference in the basal and post-PH mRNA expression of cystic fibrosis transmembrane conductance regulator (CFTR) and anion exchange isoform 2 (AE2) in livers and gallbladders from WT and TGR5 KO mice (Supporting Fig. 7A and data not shown), CFTR mRNA was significantly less up-regulated, both in liver and gallbladders from TGR5 KO, as compared to WT, mice after BDL (Supporting Fig. 7B,C). However, TGR5 may regulate ion exchange in bile at post-translational steps, through cAMP-mediated mechanisms, as proposed earlier.[15, 23] To further understand the mechanisms involved in selleck compound library excessive BA accumulation in TGR5 KO mice after PH, BDL, or upon CA feeding, we explored BA efflux at the kidney level, because TGR5 is significantly expressed in this organ (as reported previously[7, 8] and Supporting Fig. 7F). Because a significant increase in BA

efflux in urine was observed in WT, but not in TGR5 KO, mice after PH, BDL, or a 1% CA-enriched diet (Fig. 7A,B), we studied the expression of renal BA transporter genes in those experimental settings. Although multidrug resistance-related protein MRP2, MRP3, MRP4, and OST-β mRNAs were significantly up-regulated after PH in WT, MRP2 and MRP4 genes were not, or significantly less, induced in TGR5 KO kidneys (Fig. 7C,D, and Supporting Fig. find more 7D-E). These data are in line with the observed weaker BA efflux in urine from TGR5 KO mice, because MRP2 and MRP4 have been reported to transport BA into urine in kidney proximal tubule epithelial cells.[24] In line with these data, western blotting analysis of renal MRP2 revealed a weaker expression in TGR5 KO than in WT mice 48 hours after PH (Fig. 7E). Finally, treatment with the natural TGR5 ligand, oleanolic acid (OA),[25] elicited significantly stronger BA elimination in urines in WT than in TGR5 KO mice upon a 1% CA-enriched diet (Fig. 7B).

6B and Supporting Fig. 6A), strengthening the idea that TGR5 may control ionic composition of bile after PH. In agreement with these data, biliary pH, although similar in WT and TGR5 KO mice before PH, was maintained or slightly increased in WT, but significantly fell in TGR5 KO mice after PH (Fig. 6C). Of note, the defect in ion secretion in bile observed in TGR5 KO mice after PH was not secondary to cholestasis, because BDL (at 48 hours) did not inhibit, but even increased slightly, bile

flow and ionic output in WT, but not in TGR5 KO, mice (Supporting Fig. 6B). Biliary BA concentrations and outputs were not significantly different in WT and TGR5 KO mice, both before and after PH, suggesting that bile flow deregulation in TGR5 KO mice did not result from a reduced BA flow rate (Supporting Fig. 6C). Together, these data strongly suggest that TGR5-mediated signals may control adaptive ion transport in bile under circumstances Selleckchem Trichostatin A in which BA overload occurs, such as after PH and BDL. Although we did not find any

significant difference in the basal and post-PH mRNA expression of cystic fibrosis transmembrane conductance regulator (CFTR) and anion exchange isoform 2 (AE2) in livers and gallbladders from WT and TGR5 KO mice (Supporting Fig. 7A and data not shown), CFTR mRNA was significantly less up-regulated, both in liver and gallbladders from TGR5 KO, as compared to WT, mice after BDL (Supporting Fig. 7B,C). However, TGR5 may regulate ion exchange in bile at post-translational steps, through cAMP-mediated mechanisms, as proposed earlier.[15, 23] To further understand the mechanisms involved in Selleckchem STA-9090 excessive BA accumulation in TGR5 KO mice after PH, BDL, or upon CA feeding, we explored BA efflux at the kidney level, because TGR5 is significantly expressed in this organ (as reported previously[7, 8] and Supporting Fig. 7F). Because a significant increase in BA

efflux in urine was observed in WT, but not in TGR5 KO, mice after PH, BDL, or a 1% CA-enriched diet (Fig. 7A,B), we studied the expression of renal BA transporter genes in those experimental settings. Although multidrug resistance-related protein MRP2, MRP3, MRP4, and OST-β mRNAs were significantly up-regulated after PH in WT, MRP2 and MRP4 genes were not, or significantly less, induced in TGR5 KO kidneys (Fig. 7C,D, and Supporting Fig. selleck compound 7D-E). These data are in line with the observed weaker BA efflux in urine from TGR5 KO mice, because MRP2 and MRP4 have been reported to transport BA into urine in kidney proximal tubule epithelial cells.[24] In line with these data, western blotting analysis of renal MRP2 revealed a weaker expression in TGR5 KO than in WT mice 48 hours after PH (Fig. 7E). Finally, treatment with the natural TGR5 ligand, oleanolic acid (OA),[25] elicited significantly stronger BA elimination in urines in WT than in TGR5 KO mice upon a 1% CA-enriched diet (Fig. 7B).

6B and Supporting Fig. 6A), strengthening the idea that TGR5 may control ionic composition of bile after PH. In agreement with these data, biliary pH, although similar in WT and TGR5 KO mice before PH, was maintained or slightly increased in WT, but significantly fell in TGR5 KO mice after PH (Fig. 6C). Of note, the defect in ion secretion in bile observed in TGR5 KO mice after PH was not secondary to cholestasis, because BDL (at 48 hours) did not inhibit, but even increased slightly, bile

flow and ionic output in WT, but not in TGR5 KO, mice (Supporting Fig. 6B). Biliary BA concentrations and outputs were not significantly different in WT and TGR5 KO mice, both before and after PH, suggesting that bile flow deregulation in TGR5 KO mice did not result from a reduced BA flow rate (Supporting Fig. 6C). Together, these data strongly suggest that TGR5-mediated signals may control adaptive ion transport in bile under circumstances NVP-AUY922 purchase in which BA overload occurs, such as after PH and BDL. Although we did not find any

significant difference in the basal and post-PH mRNA expression of cystic fibrosis transmembrane conductance regulator (CFTR) and anion exchange isoform 2 (AE2) in livers and gallbladders from WT and TGR5 KO mice (Supporting Fig. 7A and data not shown), CFTR mRNA was significantly less up-regulated, both in liver and gallbladders from TGR5 KO, as compared to WT, mice after BDL (Supporting Fig. 7B,C). However, TGR5 may regulate ion exchange in bile at post-translational steps, through cAMP-mediated mechanisms, as proposed earlier.[15, 23] To further understand the mechanisms involved in Ulixertinib supplier excessive BA accumulation in TGR5 KO mice after PH, BDL, or upon CA feeding, we explored BA efflux at the kidney level, because TGR5 is significantly expressed in this organ (as reported previously[7, 8] and Supporting Fig. 7F). Because a significant increase in BA

efflux in urine was observed in WT, but not in TGR5 KO, mice after PH, BDL, or a 1% CA-enriched diet (Fig. 7A,B), we studied the expression of renal BA transporter genes in those experimental settings. Although multidrug resistance-related protein MRP2, MRP3, MRP4, and OST-β mRNAs were significantly up-regulated after PH in WT, MRP2 and MRP4 genes were not, or significantly less, induced in TGR5 KO kidneys (Fig. 7C,D, and Supporting Fig. selleck kinase inhibitor 7D-E). These data are in line with the observed weaker BA efflux in urine from TGR5 KO mice, because MRP2 and MRP4 have been reported to transport BA into urine in kidney proximal tubule epithelial cells.[24] In line with these data, western blotting analysis of renal MRP2 revealed a weaker expression in TGR5 KO than in WT mice 48 hours after PH (Fig. 7E). Finally, treatment with the natural TGR5 ligand, oleanolic acid (OA),[25] elicited significantly stronger BA elimination in urines in WT than in TGR5 KO mice upon a 1% CA-enriched diet (Fig. 7B).

Papatheodoridis, George N. Dalekos, Cihan Yurdaydin, Ioannis Goulis, Pauline Arends, Maria Buti, Vana Sypsa, Spilios Manolakopoulos, Giampaolo Mangia, Nikolaos Gatselis, Onur Keskin, Savvoula Savvidou,

Bettina E. Hansen, Christos Papaioannou, Kostas Galanis, Ramazan Idilman, Massimo Colombo, Rafael Esteban, Harry L. Janssen, Pietro Lampertico 5:45 PM 191: Immune correlates of chronic hepatitis B phenotypes in North America: Results from the Hepatitis B Research Network (HBRN) Jang-June Park, David K. Wong, Abdus BGB324 S. Wahed, William M. Lee, Jordan J. Feld, Norah Terrault, Mandana Khalili, Kris V. Kowdley, Daryl Lau, Richard K. Sterling, W. Ray Kim, Coleman Smith, Robert

L. Carithers, Danielle L. Levine, James Keith, Mary E. Valiga, Anna S. Lok, Kyong-Mi Chang 6:00 PM 192: Hepatitis B Virus (HBV) Reverse Seroconversion after Allogeneic Hematopoietic Stem Cell Transplantation (HSCT) and the Impact of PostTransplant Vaccination Sarah P. Hammond, Vincent T. Ho, Chinweike Ukomadu, Lindsey R. Baden, Francisco M. Marty Parallel 29: HCV Virology Monday, November 4 4:45 – 6:15 PM Room 151 MODERATORS: Stanley M. Lemon, MD Raymond selleck chemicals llc T. Chung, MD 4:45 PM 193: Simultaneous detection of hepatitis C virus and selleck chemical interferon stimulated gene expression in infected human liver Stefan F Wieland, Zuzanna Makowska, Benedetta Campana, Diego Calabrese, Michael T. Dill, Josan Chung, Francis V. Chisari, Markus H. Heim 5:00 PM 194: Persistently Infected Hepatitis C Virus Cell Culture Impairs Type I But Not The Type III IFN Signaling Partha K. Chandra, Kyoungsub Song, Darren P. Baker, Shuanghu Liu, Curt H. Hagedorn, Serge Y. Fuchs, Nathan J. Shores, Tong Wu,

Luis A. Balart, Srikanta Dash 5:15 PM 195: Expression levels of IFNL4 and other IFN-λs are determined by dinucleotide polymorphism of IFNL4 and correlate with basal expression levels of interferon stimulated genes and effect of interferon Hiromi Abe, C. Nelson Hayes, Nobuhiko Hiraga, Michio Imamura, Daiki Miki, Masataka Tsuge, Hidenori Ochi, Kazuaki Chayama 5:30 PM 196: Identification of Viral Double-stranded RNA as a Substrate for Hepatitis C Relapse and as a Target for Ribavirin Arielle L. Klepper, Francis J. Eng, Adeeb Rahman, Brannon Weeks, Ahmed El-Shamy, M. Isabel Fiel, Gonzalo Carrasco, Sasan Roayaie, Meena Bansal, Thomas D. Schiano, Andrea D.

It was a truly great innovation in the field of gastroenterology. Taishotoyama Symposiums contributed greatly to this era of sea-change. The Symposiums consisted of a wide-spectrum study groups covering gastrointestinal cancer, esophageal diseases, diseases of the small and large intestines as well as peptic

ulcers. The number of participants to the Symposiums also increased. At each Symposium, around seven to ten distinguished professionals are invited from overseas, and the Symposiums have selleck screening library become internationally known as the forum for lectures, academic presentations and lively discussions. The magnitude of the schedule that we now see is impressive. The outcomes of these Symposiums were initially featured in the APT (Alimentary Pharmacology and Therapeutics) and latterly in the JGH

(Journal of Gastroenterology and Hepatology)—they now form global information releases from Japan. Regrettably, this 15th Taishotoyama Symposium shall be the final one, and it has attracted major attention as an international Symposium in the overall medical field in Japan. Particularly, Japan ranks as a country that has made a highly significant contribution to gastroenterology. For young gastroenterologists, these Symposiums have been invaluable as a forum for discussion in English on a level with professionals from other countries. It is no exaggeration to state that it is these Symposiums that have now enabled them to proudly give presentations and hold discussions at the DDW conferences in the United States and Europe. Their presentations are also viewed as global cutting-edge in content, which alone is evidence of the major role the Symposiums have played in the field of CHIR-99021 clinical trial gastroenterology. The good memories I have are truly too numerous to mention. The main

Symposiums I enjoyed were those held in a hotel in Shimoda, and also in Hakone and Yokohama. I also recall as if only yesterday the splendid find more meeting in Washington DC. The Taisho Night event was also wonderful. The tradition of these excellent Symposiums was inaugurated by Professor Tadayoshi Takemoto, Professor Kenzo Kobayashi, Professor Eastwood and Professor Tarnawski. The Symposiums have subsequently been organized by Professor Masaki Kitajima and myself, and run by several promoters and secretaries. We always had around 150 attendees at each Symposium in the past. The constructive discussions in English and subsequent friendly exchanges have resulted in the creation of many professors. It is very sad that this shall be the last Symposium, but the march of the times has made it unavoidable. I thank Akira Uehara, the Chairman, and Akira Ohira, the President, and the other members of Taishotoyama Pharmaceutical Co., Ltd. for making these Symposiums so successful and for your worldwide contribution to gastroenterology. Lastly, I wish to express my appreciation to Asatsu-DK Inc. for arranging to feature the Symposiums in excellent international journals. “
“Harrington et al.

It was a truly great innovation in the field of gastroenterology. Taishotoyama Symposiums contributed greatly to this era of sea-change. The Symposiums consisted of a wide-spectrum study groups covering gastrointestinal cancer, esophageal diseases, diseases of the small and large intestines as well as peptic

ulcers. The number of participants to the Symposiums also increased. At each Symposium, around seven to ten distinguished professionals are invited from overseas, and the Symposiums have Sorafenib cell line become internationally known as the forum for lectures, academic presentations and lively discussions. The magnitude of the schedule that we now see is impressive. The outcomes of these Symposiums were initially featured in the APT (Alimentary Pharmacology and Therapeutics) and latterly in the JGH

(Journal of Gastroenterology and Hepatology)—they now form global information releases from Japan. Regrettably, this 15th Taishotoyama Symposium shall be the final one, and it has attracted major attention as an international Symposium in the overall medical field in Japan. Particularly, Japan ranks as a country that has made a highly significant contribution to gastroenterology. For young gastroenterologists, these Symposiums have been invaluable as a forum for discussion in English on a level with professionals from other countries. It is no exaggeration to state that it is these Symposiums that have now enabled them to proudly give presentations and hold discussions at the DDW conferences in the United States and Europe. Their presentations are also viewed as global cutting-edge in content, which alone is evidence of the major role the Symposiums have played in the field of Rapamycin gastroenterology. The good memories I have are truly too numerous to mention. The main

Symposiums I enjoyed were those held in a hotel in Shimoda, and also in Hakone and Yokohama. I also recall as if only yesterday the splendid selleck chemicals llc meeting in Washington DC. The Taisho Night event was also wonderful. The tradition of these excellent Symposiums was inaugurated by Professor Tadayoshi Takemoto, Professor Kenzo Kobayashi, Professor Eastwood and Professor Tarnawski. The Symposiums have subsequently been organized by Professor Masaki Kitajima and myself, and run by several promoters and secretaries. We always had around 150 attendees at each Symposium in the past. The constructive discussions in English and subsequent friendly exchanges have resulted in the creation of many professors. It is very sad that this shall be the last Symposium, but the march of the times has made it unavoidable. I thank Akira Uehara, the Chairman, and Akira Ohira, the President, and the other members of Taishotoyama Pharmaceutical Co., Ltd. for making these Symposiums so successful and for your worldwide contribution to gastroenterology. Lastly, I wish to express my appreciation to Asatsu-DK Inc. for arranging to feature the Symposiums in excellent international journals. “
“Harrington et al.

In temperate climates, thermal constraints make precise thermoregulation costly. Theoretical models of thermoregulation predict that species in cool environments should exhibit lower optimal temperature for performance and lower thermal preferences

to minimize thermoregulatory costs. Empirical data in support of this prediction remain equivocal because several species maintain high and constant body temperatures, even in cool environments. We studied two largely sympatric colubrid snakes, Hierophis viridiflavus and Zamenis longissimus that share selleck inhibitor numerous morphological and ecological similarities, but differ markedly in thermal preference. Our objective was to quantify their thermoregulatory strategies in the field to determine how thermal preferences translate in habitat use and performance gain. The thermophilic species, H. viridiflavus, selected open microhabitats, whereas Z. longissimus, which prefers cooler temperatures, used a greater diversity of microhabitats. The two species differed markedly in their exposure levels. Hierophis viridiflavus was constrained to shuttle between sun and shade to maintain preferred body temperatures rendering it very exposed, Sorafenib while covered microhabitats were usually thermally compatible with the

requirements of Z. longissimus. High exposure was apparently counterbalanced by higher locomotor performances in H. viridiflavus. The divergence in thermal ecology between Z. longissimus and H. viridiflavus likely reflects different trade-offs between energy gain and predator avoidance. “
“The nature of chemical defenses in poison frogs has been explored in a variety of species, and most studies focus on the types of chemical defenses and their sources. The defensive compounds of frogs are stored in dermal granular glands that have been described for several species that are chemically protected from predators and/or microorganisms. Gland ultrastructure check details is known for some

species of dendrobatoid frogs, but the relationship between body size and chemical defense has heretofore not been explored. It might be expected that the capacity for defensive protection increases as a function of body size, especially given the fact that juvenile poison frogs are known to have smaller quantities of alkaloids than adults. We examined poison glands histologically in a sample of the poison frog Oophaga pumilio to determine if the physical basis of the defensive system changes as a function of body size. We measured average gland size, estimated the number of glands, and calculated the density and percentage of skin area occupied by glands in a patch of dorsal skin for 25 individuals. For males and females, the size, number and percentage of skin area occupied by poison glands increased allometrically as a function of body size, whereas poison gland density decreased with body size.

In temperate climates, thermal constraints make precise thermoregulation costly. Theoretical models of thermoregulation predict that species in cool environments should exhibit lower optimal temperature for performance and lower thermal preferences

to minimize thermoregulatory costs. Empirical data in support of this prediction remain equivocal because several species maintain high and constant body temperatures, even in cool environments. We studied two largely sympatric colubrid snakes, Hierophis viridiflavus and Zamenis longissimus that share selleck chemical numerous morphological and ecological similarities, but differ markedly in thermal preference. Our objective was to quantify their thermoregulatory strategies in the field to determine how thermal preferences translate in habitat use and performance gain. The thermophilic species, H. viridiflavus, selected open microhabitats, whereas Z. longissimus, which prefers cooler temperatures, used a greater diversity of microhabitats. The two species differed markedly in their exposure levels. Hierophis viridiflavus was constrained to shuttle between sun and shade to maintain preferred body temperatures rendering it very exposed, PD0325901 manufacturer while covered microhabitats were usually thermally compatible with the

requirements of Z. longissimus. High exposure was apparently counterbalanced by higher locomotor performances in H. viridiflavus. The divergence in thermal ecology between Z. longissimus and H. viridiflavus likely reflects different trade-offs between energy gain and predator avoidance. “
“The nature of chemical defenses in poison frogs has been explored in a variety of species, and most studies focus on the types of chemical defenses and their sources. The defensive compounds of frogs are stored in dermal granular glands that have been described for several species that are chemically protected from predators and/or microorganisms. Gland ultrastructure check details is known for some

species of dendrobatoid frogs, but the relationship between body size and chemical defense has heretofore not been explored. It might be expected that the capacity for defensive protection increases as a function of body size, especially given the fact that juvenile poison frogs are known to have smaller quantities of alkaloids than adults. We examined poison glands histologically in a sample of the poison frog Oophaga pumilio to determine if the physical basis of the defensive system changes as a function of body size. We measured average gland size, estimated the number of glands, and calculated the density and percentage of skin area occupied by glands in a patch of dorsal skin for 25 individuals. For males and females, the size, number and percentage of skin area occupied by poison glands increased allometrically as a function of body size, whereas poison gland density decreased with body size.