Intestinal Mechanomorphological Remodeling Induced by Long-Term Low-Fiber Diet in Rabbits.

PubMed

Liu, Yue; Zhao, Jingbo; Liao, Donghua; Wang, Guixue; Gregersen, Hans

2017-12-01

Short-term feeding with low-fiber diet remodels the mechanomorphological properties in the rabbit small intestine. The aims were to study the effect of feeding low-fiber diet for 5 months on mechanomorphological properties including the collagen fraction in the rabbit intestines. Fifteen rabbits were divided into an Intervention group (IG, n = 10) fed a low-fiber diet and a Control group (CG, n = 5) fed a normal diet for 5 months. Five months later, four 10-cm-long segments obtained from the duodenum, jejunum, ileum and large intestine were used for histological and mechanical analysis, respectively. The wall thickness, wall area, mucosa and muscle layer thickness decreased whereas the submucosa layer thickness increased in the IG (p < 0.05). The collagen fraction decreased in all layers and segments in the IG (p < 0.05). The opening angle increased in the large intestine and decreased in the ileum in the IG (p < 0.05). The intestinal stress-strain curves for IG shifted to the right, indicating softening. The creep did not change in the four segments. The wall stiffness was associated with wall thickness and collagen fraction in the submucosa layer. Long-term low-fiber diet in rabbits induced histomorphometric and biomechanical remodelling of the intestines.

Total sialic acid profile in regressing and remodelling organs during the metamorphosis of marsh frog (Pelophylax ridibundus Pallas 1771).

PubMed

Kaptan, Engin; Bas, Serap Sancar; Inceli, Meliha Sengezer

2013-03-01

This study aimed to investigate the functional relationship of sialic acid in regressing and remodelling organs such as the tail, small intestine and liver during the metamorphosis of Pelophylax ridibundus. For this purpose, four groups were composed according to developmental periods by considering Gosner's criteria (1964). Our findings showed that the sialic acid content of the larval tail has an opposite profile to cell death process. Although the sialic acid content of the small intestine and liver did not change evidently during metamorphosis, it increased after the completion of metamorphosis. Frog tail extensively exhibited cell death process and decreased proliferative activity and underwent complete degeneration during metamorphic climax. In spite of increased apoptotic index, a decreased sialic acid level in the tail tissues during climax can be the indication of a death cell removal process. However, the intestine and the liver included both cell death and proliferative process and remodelling in their adult forms. Thus, their sialic acid profiles during metamorphosis were different from the tail's profile. These data show that sialic acid may be an indicator of the presence of some cellular events during metamorphosis and that it can have different roles in the developmental process depending on the organ's fate throughout metamorphosis. Copyright © 2012 John Wiley & Sons, Ltd.

Carryover effects of larval exposure to different environmental bacteria drive adult trait variation in a mosquito vector

PubMed Central

Dickson, Laura B.; Jiolle, Davy; Minard, Guillaume; Moltini-Conclois, Isabelle; Volant, Stevenn; Ghozlane, Amine; Bouchier, Christiane; Ayala, Diego; Paupy, Christophe; Moro, Claire Valiente; Lambrechts, Louis

2017-01-01

Conditions experienced during larval development of holometabolous insects can affect adult traits, but whether differences in the bacterial communities of larval development sites contribute to variation in the ability of insect vectors to transmit human pathogens is unknown. We addressed this question in the mosquito Aedes aegypti, a major arbovirus vector breeding in both sylvatic and domestic habitats in Sub-Saharan Africa. Targeted metagenomics revealed differing bacterial communities in the water of natural breeding sites in Gabon. Experimental exposure to different native bacterial isolates during larval development resulted in significant differences in pupation rate and adult body size but not life span. Larval exposure to an Enterobacteriaceae isolate resulted in decreased antibacterial activity in adult hemolymph and reduced dengue virus dissemination titer. Together, these data provide the proof of concept that larval exposure to different bacteria can drive variation in adult traits underlying vectorial capacity. Our study establishes a functional link between larval ecology, environmental microbes, and adult phenotypic variation in a holometabolous insect vector. PMID:28835919

Building a Beetle: How Larval Environment Leads to Adult Performance in a Horned Beetle

PubMed Central

Reaney, Leeann T.; Knell, Robert J.

2015-01-01

The link between the expression of the signals used by male animals in contests with the traits which determine success in those contests is poorly understood. This is particularly true in holometabolous insects such as horned beetles where signal expression is determined during metamorphosis and is fixed during adulthood, whereas performance is influenced by post-eclosion feeding. We used path analysis to investigate the relationships between larval and adult nutrition, horn and body size and fitness-related traits such as strength and testes mass in the horned beetle Euoniticellus intermedius. In males weight gain post-eclosion had a central role in determining both testes mass and strength. Weight gain was unaffected by adult nutrition but was strongly correlated with by horn length, itself determined by larval resource availability, indicating strong indirect effects of larval nutrition on the adult beetle’s ability to assimilate food and grow tissues. Female strength was predicted by a simple path diagram where strength was determined by eclosion weight, itself determined by larval nutrition: weight gain post-eclosion was not a predictor of strength in this sex. Based on earlier findings we discuss the insulin-like signalling pathway as a possible mechanism by which larval nutrition could affect adult weight gain and thence traits such as strength. PMID:26244874

Aluminum nanoparticle exposure in L1 larvae results in more severe lethality toxicity than in L4 larvae or young adults by strengthening the formation of stress response and intestinal lipofuscin accumulation in nematodes.

PubMed

Wu, Si; Lu, Jianhong; Rui, Qi; Yu, Shunhui; Cai, Ting; Wang, Dayong

2011-01-01

Toxicity of Al(2)O(3)-NPs, as compared to that of Al(2)O(3), to L1-larval, L4-larval or young adult nematodes was evaluated. When exposure was performed at L1-larval stage, the significant increases of lethality, stress response, and intestinal lipofuscin autofluorescence were observed in 6.3-203.9 mg/L of Al(2)O(3)-NPs exposed nematodes. In contrast, when exposure was performed at L4-larval or young adult stage, the significant increases of lethality and intestinal lipofuscin autofluorescence were observed in 12.7-203.9 mg/L of Al(2)O(3)-NPs exposed nematodes, and the significant inductions of stress response were detected in 25.5-203.9 mg/L of Al(2)O(3)-NPs exposed nematodes. Moreover, the lethality was significantly correlated with the stress response and the intestinal lipofuscin autofluorescence in Al(2)O(3)-NPs exposed nematodes. These data imply that Al(2)O(3)-NPs exposure in L1 larvae causes more severe lethality toxicity than in L4 larvae or young adults by strengthening the formation of stress response and intestinal lipofuscin accumulation in nematodes. Copyright © 2010 Elsevier B.V. All rights reserved.

Voltage dependent potassium channel remodeling in murine intestinal smooth muscle hypertrophy induced by partial obstruction.

PubMed

Liu, Dong-Hai; Huang, Xu; Guo, Xin; Meng, Xiang-Min; Wu, Yi-Song; Lu, Hong-Li; Zhang, Chun-Mei; Kim, Young-chul; Xu, Wen-Xie

2014-01-01

Partial obstruction of the small intestine causes obvious hypertrophy of smooth muscle cells and motility disorder in the bowel proximate to the obstruction. To identify electric remodeling of hypertrophic smooth muscles in partially obstructed murine small intestine, the patch-clamp and intracellular microelectrode recording methods were used to identify the possible electric remodeling and Western blot, immunofluorescence and immunoprecipitation were utilized to examine the channel protein expression and phosphorylation level changes in this research. After 14 days of obstruction, partial obstruction caused obvious smooth muscle hypertrophy in the proximally located intestine. The slow waves of intestinal smooth muscles in the dilated region were significantly suppressed, their amplitude and frequency were reduced, whilst the resting membrane potentials were depolarized compared with normal and sham animals. The current density of voltage dependent potassium channel (KV) was significantly decreased in the hypertrophic smooth muscle cells and the voltage sensitivity of KV activation was altered. The sensitivity of KV currents (IKV) to TEA, a nonselective potassium channel blocker, increased significantly, but the sensitivity of IKv to 4-AP, a KV blocker, stays the same. The protein levels of KV4.3 and KV2.2 were up-regulated in the hypertrophic smooth muscle cell membrane. The serine and threonine phosphorylation levels of KV4.3 and KV2.2 were significantly increased in the hypertrophic smooth muscle cells. Thus this study represents the first identification of KV channel remodeling in murine small intestinal smooth muscle hypertrophy induced by partial obstruction. The enhanced phosphorylations of KV4.3 and KV2.2 may be involved in this process.

Toxicity of the mosquito control pesticide Scourge to adult and larval grass shrimp (Palaemonetes pugio).

PubMed

Key, Peter; DeLorenzo, Marie; Gross, Kristen; Chung, Katy; Clum, Allan

2005-01-01

This study investigated the toxicity of various concentrations of technical resmethrin and Scourge on adult and larval Palaemonetes pugio, a common grass shrimp species. Two types of tests were conducted for each of the resmethrin formulations using adult and larval grass shrimp life stages, a 96-h static renewal aqueous test without sediment, and a 24-h static nonrenewal aqueous test with sediment. For resmethrin, the 96-h aqueous LC50 value for adult shrimp was 0.53 microg/L (95% confidence interval (CI): 0.46-0.60 microg/L), and for larval shrimp was 0.35 microg/L (95% CI: 0.28-0.42 microg/L). In the presence of sediment, technical resmethrin produced a 24-h LC50 value for adult shrimp of 5.44 microg/L (95% CI: 4.52-6.55 microg/L), and for larval shrimp of 2.15 microg/L (95% CI: 1.35-3.43 microg/L). For Scourge, the 96-h aqueous LC50 for adult shrimp was 2.08 microg/L (95% CI: 1.70-2.54 microg/L), and for larval shrimp was 0.36 microg/L (95% CI: 0.24-0.55 microg/L). The 24-h sediment test yielded an LC50 value of 16.12 microg/L (95% CI: 14.79-17.57 microg/L) for adult shrimp, and 14.16 microg/L (95% CI: 12.21-16.43 microg/L) for larvae. Adjusted LC50 values to reflect the 18% resmethrin concentration in Scourge are 0.37 microg/L (adult), 0.07 microg/L (larvae) for the 96-h aqueous test, and 2.90 microg/L (adult), 2.6 microg/L (larvae) for the 24-h sediment test. Larval grass shrimp were more sensitive to technical resmethrin and Scourge than the adult life stage. The results also demonstrate that synergized resmethrin is more toxic to P. pugio than the nonsynergized form, and that the presence of sediment decreases the toxicity of both resmethrin and Scourge.

[Adult intestinal malrotation associated with intestinal volvulus].

PubMed

Hernando-Almudí, Ernesto; Cerdán-Pascual, Rafael; Vallejo-Bernad, Cristina; Martín-Cuartero, Joaquín; Sánchez-Rubio, María; Casamayor-Franco, Carmen

Intestinal malrotation is a congenital anomaly of the intestinal rotation and fixation, and usually occurs in the neonatal age. Description of a clinical case associated with acute occlusive symptoms. A case of intestinal malrotation is presented in a previously asymptomatic woman of 46 years old with an intestinal obstruction, with radiology and surgical findings showing an absence of intestinal rotation. Intestinal malrotation in adults is often asymptomatic, and is diagnosed as a casual finding during a radiological examination performed for other reasons. Infrequently, it can be diagnosed in adults, associated with an acute abdomen. Copyright © 2016 Academia Mexicana de Cirugía A.C. Publicado por Masson Doyma México S.A. All rights reserved.

Efficiency of selection methods for increased ratio of pupal-larval to adult-larval weight gains in Tribolium.

PubMed

Campo, J L; Cobos, P

1994-01-12

Four lines of Tribolium castaneum were selected in each of three replicates for increased ratio of (pupal-larval) to (adult-larval) weight gains, using selection for increased (pupal-larval) weight gain (PL), selection for decreased (adult-larval) weight gain (AL), direct selection for the ratio (R) and linear selection index of larval, pupal and adult weights (I), respectively, for four generations. Linear index was calculated with economic weights of m(2) -m(3) , m(3) -m(1) and m(1) -m(2) , respectively, with m(1) , m(2) and m(3) being the means for larval, pupal and adult weights. Selection to increase the ratio is considered to be a method to maximize the mean response in (adult-larval) weight while controlling the response in (pupal-adult) weight, and as a form of antagonistic selection to increase the weight gain during a given age period relative to the gain at another age period. Larval, pupal and adult weights were measured at 14, 21 and 28 days after adult emergence, respectively. The selected proportion was 20 % in all lines. The response observed for the ratio differed significantly among lines (p < 0.01), with the I and AL lines having the greatest responses. Line R was less effective in improving the objective of selection, while line PL appeared to be inappropriate. The observed responses for the numerator and denominator weight gains were positive in line PL, and negative in the AL, R and I lines. All lines apart from line PL decreased the (adult-larval) weight, holding (pupal-adult) weight constant. Larval weight showed the greatest influence on the response for the objective of selection. The results for this greater than 1 ratio are compared with results of others for smaller than 1 ratios, in which indirect selection for increased numerator is the more efficient alternative to the selection index. ZUSAMMENFASSUNG: Effizienz Selektionsverfahren zur Verbesserung des Quotienten der Gewichtsentwicklung zwischen Puppe/Larve und Käfer/Larve bei

The Turning Point for Morphomechanical Remodeling During Complete Intestinal Obstruction in Rats Occurs After 12-24 h.

PubMed

Sun, Daming; Zhao, Jingbo; Liao, Donghua; Huang, Zhiyong; Gregersen, Hans

2018-05-01

Intestinal obstruction prompts luminal dilation and wall remodeling proximal to the site of obstruction. Studies on temporal and spatial morphomechanical remodeling are needed for comprehending the pathophysiology of acute intestinal obstruction. The aim was to estimate the no-load and zero-stress morphomechanical properties in circumferential and longitudinal direction at 0, 6, 12, 24, 36, and 48 h after complete intestinal obstruction. Obstruction of the distal ileum was created surgically by placement of a polyethylene ring for up to 48 h in 30 rats. Sham and normal groups were also studied (n = 12). Five 6 cm-long intestinal segments proximal to the obstruction site were used for histological, morphometric and mechanical analysis at the designated times. Morphomechanical changes were huge but only subtle changes were observed between the 5 segments during the obstruction period. Due to dilation, the serosal length and mucosal length increased continuously from 6 to 48 h (p < 0.001). The wall area increased at 24 h and beyond (p < 0.001), demonstrating tissue growth. The opening and bending angle decreased to minimum values at 24 h where after the opening angle increased and the bending angle returned to pre-obstruction levels. For the residual stretch ratios and the position of the neutral axis the turning point was found after 24 h. Histologically, the thickness and area of most wall layers were quite stable for the first 12 h but with an increase at the 24 h time point that continued to the 48 h time point. The most pronounced change was found for the circumferential muscle layer (p < 0.05). Analysis of picrosirius red stained slides showed that submucosal type 3 collagen fraction increased significantly (p < 0.001), whereas the fraction of type 1 collagen decreased (p < 0.001). In conclusion, pronounced time-dependent morphomechanical remodeling was found. The obstructed intestine went from dilation remodeling to growth remodeling

Temperature during larval development and adult maintenance influences the survival of Anopheles gambiae s.s.

PubMed

Christiansen-Jucht, Céline; Parham, Paul E; Saddler, Adam; Koella, Jacob C; Basáñez, María-Gloria

2014-11-05

Malaria transmission depends on vector life-history parameters and population dynamics, and particularly on the survival of adult Anopheles mosquitoes. These dynamics are sensitive to climatic and environmental factors, and temperature is a particularly important driver. Data currently exist on the influence of constant and fluctuating adult environmental temperature on adult Anopheles gambiae s.s. survival and on the effect of larval environmental temperature on larval survival, but none on how larval temperature affects adult life-history parameters. Mosquito larvae and pupae were reared individually at different temperatures (23 ± 1°C, 27 ± 1°C, 31 ± 1°C, and 35 ± 1°C), 75 ± 5% relative humidity. Upon emergence into imagoes, individual adult females were either left at their larval temperature or placed at a different temperature within the range above. Survival was monitored every 24 hours and data were analysed using non-parametric and parametric methods. The Gompertz distribution fitted the survivorship data better than the gamma, Weibull, and exponential distributions overall and was adopted to describe mosquito mortality rates. Increasing environmental temperature during the larval stages decreased larval survival (p < 0.001). Increases of 4°C (from 23°C to 27°C, 27°C to 31°C, and 31°C to 35°C), 8°C (27°C to 35°C) and 12°C (23°C to 35°C) statistically significantly increased larval mortality (p < 0.001). Higher environmental temperature during the adult stages significantly lowered adult survival overall (p < 0.001), with increases of 4°C and 8°C significantly influencing survival (p < 0.001). Increasing the larval environment temperature also significantly increased adult mortality overall (p < 0.001): a 4°C increase (23°C to 27°C) did not significantly affect adult survival (p > 0.05), but an 8°C increase did (p < 0.05). The effect of a 4°C increase in larval temperature from 27

Safety of methionine, a novel biopesticide, to adult and larval honey bees (Apis mellifera L.).

PubMed

Weeks, Emma N I; Schmehl, Daniel R; Baniszewski, Julie; Tomé, Hudson V V; Cuda, James P; Ellis, James D; Stevens, Bruce R

2018-03-01

Methionine is an essential/indispensible amino acid nutrient required by adult and larval honey bees (Apis mellifera L. [Hymenoptera: Apidae]). Bees are unable to rear broods on pollen deficient in methionine, and reportedly behaviorally avoid collecting pollen or nectar from florets deficient in methioinine. In contrast, it has been demonstrated that methionine is toxic to certain pest insects; thus it has been proposed as an effective biopesticide. As an ecofriendly integrated pest management agent, methionine boasts a novel mode of action differentiating it from conventional pesticides, while providing non-target safety. Pesticides that minimize collateral effects on bees are desirable, given the economic and ecological concerns about honey bee health. The aim of the present study was to assess the potential impact of the biopesticide methionine on non-target adult and larval honey bees. Acute contact adult toxicology bioassays, oral adult assessments and chronic larval toxicity assessments were performed as per U.S. Environmental Protection Agency (EPA) requirements. Our results demonstrated that methionine fits the U.S. EPA category of practically nontoxic (i.e. lethal dose to 50% mortality or LD 50 > 11µg/bee) to adult honey bees. The contact LD 50 was > 25µg/bee and the oral LD 50 was > 100µg/bee. Mortality was observed in larval bees that ingested DL-methionine (effective concentration to 50% mortality or EC 50 560µg/bee). Therefore, we conclude that methionine poses little threat to the health of the honey bee, due to unlikely exposure at concentrations shown to elicit toxic effects. Copyright © 2017 Elsevier Inc. All rights reserved.

Adult-specific insulin-producing neurons in Drosophila melanogaster.

PubMed

Ohhara, Yuya; Kobayashi, Satoru; Yamakawa-Kobayashi, Kimiko; Yamanaka, Naoki

2018-06-01

Holometabolous insects undergo metamorphosis to reorganize their behavioral and morphological features into adult-specific ones. In the central nervous system (CNS), some larval neurons undergo programmed cell death, whereas others go through remodeling of axonal and dendritic arbors to support functions of re-established adult organs. Although there are multiple neuropeptides that have stage-specific roles in holometabolous insects, the reorganization pattern of the entire neuropeptidergic system through metamorphosis still remains largely unclear. In this study, we conducted a mapping and lineage tracing of peptidergic neurons in the larval and adult CNS by using Drosophila genetic tools. We found that Diuretic hormone 44-producing median neurosecretory cells start expressing Insulin-like peptide 2 in the pharate adult stage. This neuronal cluster projects to the corpora cardiaca and dorsal vessel in both larval and adult stages, and also innervates an adult-specific structure in the digestive tract, the crop. We propose that the adult-specific insulin-producing cells may regulate functions of the digestive system in a stage-specific manner. Our study provides a neuroanatomical basis for understanding remodeling of the neuropeptidergic system during insect development and evolution. © 2018 Wiley Periodicals, Inc.

Intestinal lymphangiectasia in adults.

PubMed

Freeman, Hugh James; Nimmo, Michael

2011-02-15

Intestinal lymphangiectasia in the adult may be characterized as a disorder with dilated intestinal lacteals causing loss of lymph into the lumen of the small intestine and resultant hypoproteinemia, hypogammaglobulinemia, hypoalbuminemia and reduced number of circulating lymphocytes or lymphopenia. Most often, intestinal lymphangiectasia has been recorded in children, often in neonates, usually with other congenital abnormalities but initial definition in adults including the elderly has become increasingly more common. Shared clinical features with the pediatric population such as bilateral lower limb edema, sometimes with lymphedema, pleural effusion and chylous ascites may occur but these reflect the severe end of the clinical spectrum. In some, diarrhea occurs with steatorrhea along with increased fecal loss of protein, reflected in increased fecal alpha-1-antitrypsin levels, while others may present with iron deficiency anemia, sometimes associated with occult small intestinal bleeding. Most lymphangiectasia in adults detected in recent years, however, appears to have few or no clinical features of malabsorption. Diagnosis remains dependent on endoscopic changes confirmed by small bowel biopsy showing histological evidence of intestinal lymphangiectasia. In some, video capsule endoscopy and enteroscopy have revealed more extensive changes along the length of the small intestine. A critical diagnostic element in adults with lymphangiectasia is the exclusion of entities (e.g. malignancies including lymphoma) that might lead to obstruction of the lymphatic system and "secondary" changes in the small bowel biopsy. In addition, occult infectious (e.g. Whipple's disease from Tropheryma whipplei) or inflammatory disorders (e.g. Crohn's disease) may also present with profound changes in intestinal permeability and protein-losing enteropathy that also require exclusion. Conversely, rare B-cell type lymphomas have also been described even decades following initial

Intestinal lymphangiectasia in adults

PubMed Central

Freeman, Hugh James; Nimmo, Michael

2011-01-01

Intestinal lymphangiectasia in the adult may be characterized as a disorder with dilated intestinal lacteals causing loss of lymph into the lumen of the small intestine and resultant hypoproteinemia, hypogammaglobulinemia, hypoalbuminemia and reduced number of circulating lymphocytes or lymphopenia. Most often, intestinal lymphangiectasia has been recorded in children, often in neonates, usually with other congenital abnormalities but initial definition in adults including the elderly has become increasingly more common. Shared clinical features with the pediatric population such as bilateral lower limb edema, sometimes with lymphedema, pleural effusion and chylous ascites may occur but these reflect the severe end of the clinical spectrum. In some, diarrhea occurs with steatorrhea along with increased fecal loss of protein, reflected in increased fecal alpha-1-antitrypsin levels, while others may present with iron deficiency anemia, sometimes associated with occult small intestinal bleeding. Most lymphangiectasia in adults detected in recent years, however, appears to have few or no clinical features of malabsorption. Diagnosis remains dependent on endoscopic changes confirmed by small bowel biopsy showing histological evidence of intestinal lymphangiectasia. In some, video capsule endoscopy and enteroscopy have revealed more extensive changes along the length of the small intestine. A critical diagnostic element in adults with lymphangiectasia is the exclusion of entities (e.g. malignancies including lymphoma) that might lead to obstruction of the lymphatic system and “secondary” changes in the small bowel biopsy. In addition, occult infectious (e.g. Whipple’s disease from Tropheryma whipplei) or inflammatory disorders (e.g. Crohn’s disease) may also present with profound changes in intestinal permeability and protein-losing enteropathy that also require exclusion. Conversely, rare B-cell type lymphomas have also been described even decades following

Short-term developmental effects and potential mechanisms of azoxystrobin in larval and adult zebrafish (Danio rerio).

PubMed

Cao, Fangjie; Wu, Peizhuo; Huang, Lan; Li, Hui; Qian, Le; Pang, Sen; Qiu, Lihong

2018-05-01

Previous study indicated that azoxystrobin had high acute toxicity to zebrafish, and larval zebrafish were more sensitive to azoxystrobin than adult zebrafish. The objective of the present study was to investigate short-term developmental effects and potential mechanisms of azoxystrobin in larval and adult zebrafish. After zebrafish embryos and adults were exposed to 0.01, 0.05 and 0.20 mg/L azoxystrobin (equal to 25, 124 and 496 nM azoxystrobin, respectively) for 8 days, the lethal effect, physiological responses, liver histology, mitochondrial ultrastructure, and expression alteration of genes related to mitochondrial respiration, oxidative stress, cell apoptosis and innate immune response were determined. The results showed that there was no significant effect on larval and adult zebrafish after exposure to 0.01 mg/L azoxystrobin. However, increased ROS, MDA concentration and il1b in larval zebrafish, as well as increased il1b, il8 and cxcl-c1c in adult zebrafish were induced after exposure to 0.05 mg/L azoxystrobin. Reduced mitochondrial complex III activity and ATP concentration, increased SOD activity, ROS and MDA concentration, decreased cytb, as well as increased sod1, sod2, cat, il1b, il8 and cxcl-c1c were observed both in larval and adult zebrafish after exposure to 0.20 mg/L azoxystrobin; meanwhile, increased p53, bax, apaf1 and casp9, alteration of liver histology and mitochondrial ultrastructure in larval zebrafish, and alteration of mitochondrial ultrastructure in adult zebrafish were also induced. The results demonstrated that azoxytrobin induced short-term developmental effects on larval zebrafish and adult zebrafish, including mitochondrial dysfunction, oxidative stress, cell apoptosis and innate immune response. Statistical analysis indicated that azoxystrobin induced more negative effects on larval zebrafish, which might be the reason for the differences of developmental toxicity between larval and adult zebrafish caused by

Effects of arginine vasotocin and mesotocin on the activation and development of amiloride-blockable short-circuit current across larval, adult, and cultured larval bullfrog skins.

PubMed

Takada, Makoto; Fujimaki-Aoba, Kayo; Hokari, Shigeru

2010-03-01

Amphibian skin has osmoregulatory functions, with Na(+) crossing from outside to inside. Na(+) transport can be measured as the short-circuit current (SCC). We investigated the short-term and long-term effects of arginine vasotocin (AVT) and mesotocin (MT) (which modulate Na(+) transport) on the activation and development of an amiloride-blockable SCC (adult-type feature) in larval, adult, and corticoid-cultured larval bullfrog skins. We found: (1) AVT-receptor (AVT-R) and MT-receptor (MT-R) mRNAs could be detected in both larval and adult skins, (2) in the short term (within 60 min), the larval SCC (amiloride-stimulated SCC) was increased by AVT, forskolin, and MT, suggesting that AVT and MT did not activate the inactive ENaC (epithelial sodium channel) protein thought to be expressed in larval skin, (3) in the short term (within 90 min), AVT, forskolin, and MT stimulated the adult SCC (amiloride-blockable SCC), (4) AVT and MT increased both the larval and adult SCC via receptors insensitive to OPC-21268 (an antagonist of the V(1)-type receptor), OPC-31260 (an antagonist of the V(2)-type receptor), and ([d(CH(2))(5),Tyr(Me)(2),Thr(4),Orn(8),des-Gly-NH (2) (9) ]VT) (an antagonist of the oxytocin receptor), (5) culturing EDTA-treated larval skin with corticoids supplemented with AVT (1 microM) or MT (1 microM) for 2 weeks (long-term effects of AVT and MT) did not alter the corticoid-induced development of an amiloride-blockable SCC (adult-type feature). AVT and MT thus have the potential to stimulate SCC though channels that are already expressed, but they may not influence the development of the amiloride-blockable SCC (an adult-type feature) in larval skin.

Larval starvation improves metabolic response to adult starvation in honey bees (Apis mellifera L.).

PubMed

Wang, Ying; Campbell, Jacob B; Kaftanoglu, Osman; Page, Robert E; Amdam, Gro V; Harrison, Jon F

2016-04-01

Environmental changes during development have long-term effects on adult phenotypes in diverse organisms. Some of the effects play important roles in helping organisms adapt to different environments, such as insect polymorphism. Others, especially those resulting from an adverse developmental environment, have a negative effect on adult health and fitness. However, recent studies have shown that those phenotypes influenced by early environmental adversity have adaptive value under certain (anticipatory) conditions that are similar to the developmental environment, though evidence is mostly from morphological and behavioral observations and it is still rare at physiological and molecular levels. In the companion study, we applied a short-term starvation treatment to fifth instar honey bee larvae and measured changes in adult morphology, starvation resistance, hormonal and metabolic physiology and gene expression. Our results suggest that honey bees can adaptively respond to the predicted nutritional stress. In the present study, we further hypothesized that developmental starvation specifically improves the metabolic response of adult bees to starvation instead of globally affecting metabolism under well-fed conditions. Here, we produced adult honey bees that had experienced a short-term larval starvation, then we starved them for 12 h and monitored metabolic rate, blood sugar concentrations and metabolic reserves. We found that the bees that experienced larval starvation were able to shift to other fuels faster and better maintain stable blood sugar levels during starvation. However, developmental nutritional stress did not change metabolic rates or blood sugar levels in adult bees under normal conditions. Overall, our study provides further evidence that early larval starvation specifically improves the metabolic responses to adult starvation in honey bees. © 2016. Published by The Company of Biologists Ltd.

Larval and adult environmental temperatures influence the adult reproductive traits of Anopheles gambiae s.s.

PubMed

Christiansen-Jucht, Céline D; Parham, Paul E; Saddler, Adam; Koella, Jacob C; Basáñez, María-Gloria

2015-09-17

Anopheles mosquito life-history parameters and population dynamics strongly influence malaria transmission, and environmental factors, particularly temperature, strongly affect these parameters. There are currently some studies on how temperature affects Anopheles gambiae s.s. survival but very few exist examining other life-history traits. We investigate here the effect of temperature on population dynamics parameters. Anopheles gambiae s.s. immatures were reared individually at 23 ± 1 °C, 27 ± 1 °C, 31 ± 1 °C, and 35 ± 1 °C, and adults were held at their larval temperature or at one of the other temperatures. Larvae were checked every 24 h for development to the next stage and measured for size; wing length was measured as a proxy for adult size. Females were blood fed three times, and the number of females feeding and laying eggs was counted. The numbers of eggs and percentage of eggs hatched were recorded. Increasing temperatures during the larval stages resulted in significantly smaller larvae (p = 0.005) and smaller adults (p < 0.001). Adult temperature had no effect on the time to egg laying, and the larval temperature of adults only affected the incubation period of the first egg batch. Temperature influenced the time to hatching of eggs, as well as the time to development at every stage. The number of eggs laid was highest when adults were kept at 27 °C, and lowest at 31 °C, and higher adult temperatures decreased the proportion of eggs hatching after the second and third blood meal. Higher adult temperatures significantly decreased the probability of blood feeding, but the larval temperature of adults had no influence on the probability of taking a blood meal. Differences were observed between the first, second, and third blood meal in the times to egg laying and hatching, number of eggs laid, and probabilities of feeding and laying eggs. Our study shows that environmental temperature during the larval stages as

Flexible responses to visual and olfactory stimuli by foraging Manduca sexta: larval nutrition affects adult behaviour.

PubMed

Goyret, Joaquín; Kelber, Almut; Pfaff, Michael; Raguso, Robert A

2009-08-07

Here, we show that the consequences of deficient micronutrient (beta-carotene) intake during larval stages of Manduca sexta are carried across metamorphosis, affecting adult behaviour. Our manipulation of larval diet allowed us to examine how developmental plasticity impacts the interplay between visual and olfactory inputs on adult foraging behaviour. Larvae of M. sexta were reared on natural (Nicotiana tabacum) and artificial laboratory diets containing different concentrations of beta-carotene (standard diet, low beta-carotene, high beta-carotene and cornmeal). This vitamin-A precursor has been shown to be crucial for photoreception sensitivity in the retina of M. sexta. After completing development, post-metamorphosis, starved adults were presented with artificial feeders that could be either scented or unscented. Regardless of their larval diet, adult moths fed with relatively high probabilities on scented feeders. When feeders were unscented, moths reared on tobacco were more responsive than moths reared on beta-carotene-deficient artificial diets. Strikingly, moths reared on artificial diets supplemented with increasing amounts of beta-carotene (low beta and high beta) showed increasing probabilities of response to scentless feeders. We discuss these results in relationship to the use of complex, multi-modal sensory information by foraging animals.

Flexible responses to visual and olfactory stimuli by foraging Manduca sexta: larval nutrition affects adult behaviour

PubMed Central

Goyret, Joaquín; Kelber, Almut; Pfaff, Michael; Raguso, Robert A.

2009-01-01

Here, we show that the consequences of deficient micronutrient (β-carotene) intake during larval stages of Manduca sexta are carried across metamorphosis, affecting adult behaviour. Our manipulation of larval diet allowed us to examine how developmental plasticity impacts the interplay between visual and olfactory inputs on adult foraging behaviour. Larvae of M. sexta were reared on natural (Nicotiana tabacum) and artificial laboratory diets containing different concentrations of β-carotene (standard diet, low β-carotene, high β-carotene and cornmeal). This vitamin-A precursor has been shown to be crucial for photoreception sensitivity in the retina of M. sexta. After completing development, post-metamorphosis, starved adults were presented with artificial feeders that could be either scented or unscented. Regardless of their larval diet, adult moths fed with relatively high probabilities on scented feeders. When feeders were unscented, moths reared on tobacco were more responsive than moths reared on β-carotene-deficient artificial diets. Strikingly, moths reared on artificial diets supplemented with increasing amounts of β-carotene (low β and high β) showed increasing probabilities of response to scentless feeders. We discuss these results in relationship to the use of complex, multi-modal sensory information by foraging animals. PMID:19419987

Differential muscle regulatory factor gene expression between larval and adult myogenesis in the frog Xenopus laevis: adult myogenic cell-specific myf5 upregulation and its relation to the notochord suppression of adult muscle differentiation.

PubMed

Yamane, Hitomi; Nishikawa, Akio

2013-08-01

During Xenopus laevis metamorphosis, larval-to-adult muscle conversion depends on the differential responses of adult and larval myogenic cells to thyroid hormone. Essential differences in cell growth, differentiation, and hormone-dependent life-or-death fate have been reported between cultured larval (tail) and adult (hindlimb) myogenic cells. A previous study revealed that tail notochord cells suppress terminal differentiation in adult (but not larval) myogenic cells. However, little is known about the differences in expression patterns of myogenic regulatory factors (MRF) and the satellite cell marker Pax7 between adult and larval myogenic cells. In the present study, we compared mRNA expression of these factors between the two types. At first, reverse transcription polymerase chain reaction analysis of hindlimb buds showed sequential upregulation of myf5, myogenin, myod, and mrf4 during stages 50-54, when limb buds elongate and muscles begin to form. By contrast, in the tail, there was no such increase during the same period. Secondary, these results were duplicated in vitro: adult myogenic cells upregulated myf5, myod, and pax7 in the early culture period, followed by myogenin upregulation and myotube differentiation, while larval myogenic cells did not upregulate these genes and precociously started myotube differentiation. Thirdly, myf5 upregulation and early-phase proliferation in adult myogenic cells were potently inhibited by the presence of notochord cells, suggesting that notochord cells suppress adult myogenesis through inhibiting the transition from Myf5(-) stem cells to Myf5(+) committed myoblasts. All of the data presented here suggest that myf5 upregulation can be a good criterion for the activation of adult myogenesis during X. laevis metamorphosis.

The study of muscle remodeling in Drosophila metamorphosis using in vivo microscopy and bioimage informatics

PubMed Central

2012-01-01

Background Metamorphosis in insects transforms the larval into an adult body plan and comprises the destruction and remodeling of larval and the generation of adult tissues. The remodeling of larval into adult muscles promises to be a genetic model for human atrophy since it is associated with dramatic alteration in cell size. Furthermore, muscle development is amenable to 3D in vivo microscopy at high cellular resolution. However, multi-dimensional image acquisition leads to sizeable amounts of data that demand novel approaches in image processing and analysis. Results To handle, visualize and quantify time-lapse datasets recorded in multiple locations, we designed a workflow comprising three major modules. First, the previously introduced TLM-converter concatenates stacks of single time-points. The second module, TLM-2D-Explorer, creates maximum intensity projections for rapid inspection and allows the temporal alignment of multiple datasets. The transition between prepupal and pupal stage serves as reference point to compare datasets of different genotypes or treatments. We demonstrate how the temporal alignment can reveal novel insights into the east gene which is involved in muscle remodeling. The third module, TLM-3D-Segmenter, performs semi-automated segmentation of selected muscle fibers over multiple frames. 3D image segmentation consists of 3 stages. First, the user places a seed into a muscle of a key frame and performs surface detection based on level-set evolution. Second, the surface is propagated to subsequent frames. Third, automated segmentation detects nuclei inside the muscle fiber. The detected surfaces can be used to visualize and quantify the dynamics of cellular remodeling. To estimate the accuracy of our segmentation method, we performed a comparison with a manually created ground truth. Key and predicted frames achieved a performance of 84% and 80%, respectively. Conclusions We describe an analysis pipeline for the efficient handling and

Blue light-induced immunosuppression in Bactrocera dorsalis adults, as a carryover effect of larval exposure.

PubMed

Tariq, K; Noor, M; Hori, M; Ali, A; Hussain, A; Peng, W; Chang, C-J; Zhang, H

2017-12-01

Detrimental effects of ultraviolet (UV) light on living organisms are well understood, little is known about the effects of blue light irradiation. Although a recent study revealed that blue light caused more harmful effects on insects than UV light and blue light irradiation killed insect pests of various orders including Diptera, the effects of blue light on physiology of insects are still largely unknown. Here we studied the effects of blue light irradiation on cuticular melanin in larval and the immune response in adult stage of Bactrocera dorsalis. We also evaluated the effects of blue light exposure in larval stage on various age and mass at metamorphosis and the mediatory role of cuticular melanin in carryover effects of larval stressors across metamorphosis. We found that larvae exposed to blue light decreased melanin contents in their exoskeleton with smaller mass and delayed metamorphosis than insects reared without blue light exposure. Across metamorphosis, lower melanotic encapsulation response and higher susceptibility to Beauveria bassiana was detected in adults that had been exposed to blue light at their larval stage, thereby constituting the first evidence that blue light impaired adult immune function in B. dorsalis as a carryover effect of larval exposure.

Thyroid hormone regulation of adult intestinal stem cells: Implications on intestinal development and homeostasis.

PubMed

Sun, Guihong; Roediger, Julia; Shi, Yun-Bo

2016-12-01

Organ-specific adult stem cells are essential for organ homeostasis, tissue repair and regeneration. The formation of such stem cells often takes place during postembryonic development, a period around birth in mammals when plasma thyroid hormone concentration is high. The life-long self-renewal of the intestinal epithelium has made mammalian intestine a valuable model to study the function and regulation and adult stem cells. On the other hand, much less is known about how the adult intestinal stem cells are formed during vertebrate development. Here, we will review some recent progresses on this subject, focusing mainly on the formation of the adult intestine during Xenopus metamorphosis. We will discuss the role of thyroid hormone signaling pathway in the process and potential molecular conservations between amphibians and mammals as well as the implications in organ homeostasis and human diseases.

Intestinal Microbiota in Healthy Adults: Temporal Analysis Reveals Individual and Common Core and Relation to Intestinal Symptoms

PubMed Central

Nikkilä, Janne; Immonen, Outi; Kekkonen, Riina; Lahti, Leo; Palva, Airi; de Vos, Willem M.

2011-01-01

Background While our knowledge of the intestinal microbiota during disease is accumulating, basic information of the microbiota in healthy subjects is still scarce. The aim of this study was to characterize the intestinal microbiota of healthy adults and specifically address its temporal stability, core microbiota and relation with intestinal symptoms. We carried out a longitudinal study by following a set of 15 healthy Finnish subjects for seven weeks and regularly assessed their intestinal bacteria and archaea with the Human Intestinal Tract (HIT)Chip, a phylogenetic microarray, in conjunction with qPCR analyses. The health perception and occurrence of intestinal symptoms was recorded by questionnaire at each sampling point. Principal Findings A high overall temporal stability of the microbiota was observed. Five subjects showed transient microbiota destabilization, which correlated not only with the intake of antibiotics but also with overseas travelling and temporary illness, expanding the hitherto known factors affecting the intestinal microbiota. We identified significant correlations between the microbiota and common intestinal symptoms, including abdominal pain and bloating. The most striking finding was the inverse correlation between Bifidobacteria and abdominal pain: subjects who experienced pain had over five-fold less Bifidobacteria compared to those without pain. Finally, a novel computational approach was used to define the common core microbiota, highlighting the role of the analysis depth in finding the phylogenetic core and estimating its size. The in-depth analysis suggested that we share a substantial number of our intestinal phylotypes but as they represent highly variable proportions of the total community, many of them often remain undetected. Conclusions/Significance A global and high-resolution microbiota analysis was carried out to determine the temporal stability, the associations with intestinal symptoms, and the individual and common

Remodeling of the abdominal epithelial monolayer during the larva-pupa-adult transformation of Manduca.

PubMed

Nardi, James B; Bee, Charles Mark; Wallace, Catherine Lee

2018-06-01

During metamorphosis of insect epithelial monolayers, cells die, divide, and rearrange. In Drosophila undifferentiated diploid cells destined to form the adult cuticle of each abdominal segment segregate early in development from the surrounding polyploid larval epithelial cells of that segment as eight groups of diploid histoblast cells. The larval polyploid cells are programmed to die and be replaced by divisions and rearrangements of histoblast cells. By contrast, abdominal epithelial cells of Manduca larvae form a monolayer of cells representing different ploidy levels with no definitive segregation of diploid cells destined to form adult structures. These epithelial cells of mixed ploidy levels produce a thick smooth larval cuticle with sparsely distributed sensory bristles. Adult descendants of this larval monolayer produce a thinner cuticle with densely packed scale cells. The transition between these differentiated states of Manduca involves divisions of cells, changes in ploidy levels, and sorting of certain polyploid cells into circular rosette patches to minimize contacts of these polyploid cells with surrounding cells of equal or smaller size. Cells within the rosettes and some surrounding cells are destined to die and be replaced by remaining epithelial cells of uniform size and ploidy at pupa-adult apolysis. Copyright © 2018 Elsevier Inc. All rights reserved.

Long-Term Changes in the Distributions of Larval and Adult Fish in the Northeast U.S. Shelf Ecosystem.

PubMed

Walsh, Harvey J; Richardson, David E; Marancik, Katrin E; Hare, Jonathan A

2015-01-01

Many studies have documented long-term changes in adult marine fish distributions and linked these changes to climate change and multi-decadal climate variability. Most marine fish, however, have complex life histories with morphologically distinct stages, which use different habitats. Shifts in distribution of one stage may affect the connectivity between life stages and thereby impact population processes including spawning and recruitment. Specifically, many marine fish species have a planktonic larval stage, which lasts from weeks to months. We compared the spatial distribution and seasonal occurrence of larval fish in the Northeast U.S. Shelf Ecosystem to test whether spatial and temporal distributions changed between two decades. Two large-scale ichthyoplankton programs sampled using similar methods and spatial domain each decade. Adult distributions from a long-term bottom trawl survey over the same time period and spatial area were also analyzed using the same analytical framework to compare changes in larval and adult distributions between the two decades. Changes in spatial distribution of larvae occurred for 43% of taxa, with shifts predominately northward (i.e., along-shelf). Timing of larval occurrence shifted for 49% of the larval taxa, with shifts evenly split between occurring earlier and later in the season. Where both larvae and adults of the same species were analyzed, 48% exhibited different shifts between larval and adult stages. Overall, these results demonstrate that larval fish distributions are changing in the ecosystem. The spatial changes are largely consistent with expectations from a changing climate. The temporal changes are more complex, indicating we need a better understanding of reproductive timing of fishes in the ecosystem. These changes may impact population productivity through changes in life history connectivity and recruitment, and add to the accumulating evidence for changes in the Northeast U.S. Shelf Ecosystem with

Long-Term Changes in the Distributions of Larval and Adult Fish in the Northeast U.S. Shelf Ecosystem

PubMed Central

2015-01-01

Many studies have documented long-term changes in adult marine fish distributions and linked these changes to climate change and multi-decadal climate variability. Most marine fish, however, have complex life histories with morphologically distinct stages, which use different habitats. Shifts in distribution of one stage may affect the connectivity between life stages and thereby impact population processes including spawning and recruitment. Specifically, many marine fish species have a planktonic larval stage, which lasts from weeks to months. We compared the spatial distribution and seasonal occurrence of larval fish in the Northeast U.S. Shelf Ecosystem to test whether spatial and temporal distributions changed between two decades. Two large-scale ichthyoplankton programs sampled using similar methods and spatial domain each decade. Adult distributions from a long-term bottom trawl survey over the same time period and spatial area were also analyzed using the same analytical framework to compare changes in larval and adult distributions between the two decades. Changes in spatial distribution of larvae occurred for 43% of taxa, with shifts predominately northward (i.e., along-shelf). Timing of larval occurrence shifted for 49% of the larval taxa, with shifts evenly split between occurring earlier and later in the season. Where both larvae and adults of the same species were analyzed, 48% exhibited different shifts between larval and adult stages. Overall, these results demonstrate that larval fish distributions are changing in the ecosystem. The spatial changes are largely consistent with expectations from a changing climate. The temporal changes are more complex, indicating we need a better understanding of reproductive timing of fishes in the ecosystem. These changes may impact population productivity through changes in life history connectivity and recruitment, and add to the accumulating evidence for changes in the Northeast U.S. Shelf Ecosystem with

Using adult mosquitoes to transfer insecticides to Aedes aegypti larval habitats

PubMed Central

Devine, Gregor J.; Perea, Elvira Zamora; Killeen, Gerry F.; Stancil, Jeffrey D.; Clark, Suzanne J.; Morrison, Amy C.

2009-01-01

Vector control is a key means of combating mosquito-borne diseases and the only tool available for tackling the transmission of dengue, a disease for which no vaccine, prophylaxis, or therapeutant currently exists. The most effective mosquito control methods include a variety of insecticidal tools that target adults or juveniles. Their successful implementation depends on impacting the largest proportion of the vector population possible. We demonstrate a control strategy that dramatically improves the efficiency with which high coverage of aquatic mosquito habitats can be achieved. The method exploits adult mosquitoes as vehicles of insecticide transfer by harnessing their fundamental behaviors to disseminate a juvenile hormone analogue (JHA) between resting and oviposition sites. A series of field trials undertaken in an Amazon city (Iquitos, Peru) showed that the placement of JHA dissemination stations in just 3–5% of the available resting area resulted in almost complete coverage of sentinel aquatic habitats. More than control mortality occurred in 95–100% of the larval cohorts of Aedes aegypti developing at those sites. Overall reductions in adult emergence of 42–98% were achieved during the trials. A deterministic simulation model predicts amplifications in coverage consistent with our observations and highlights the importance of the residual activity of the insecticide for this technique. PMID:19561295

Apo-14 is required for digestive system organogenesis during fish embryogenesis and larval development.

PubMed

Xia, Jian-Hong; Liu, Jing-Xia; Zhou, Li; Li, Zhi; Gui, Jian-Fang

2008-01-01

Apo-14 is a fish-specific apolipoprotein and its biological function remains unknown. In this study, CagApo-14 was cloned from gibel carp (Carassius auratus gibelio) and its expression pattern was investigated during embryogenesis and early larval development. The CagApo-14 transcript and its protein product were firstly localized in the yolk syncytial layer at a high level during embryogenesis, and then found to be restricted to the digestive system including liver and intestine in later embryos and early larvae. Immunofluorescence staining in larvae and adults indicated that Cag Apo-14 protein was predominantly synthesized in and excreted from sinusoidal endothelial cells of liver tissue. Morpholino knockdown of Cag Apo-14 resulted in severe disruption of digestive organs including liver, intestine, pancreas and swim bladder. Moreover, yolk lipid transportation and utilization were severely affected in the Cag Apo-14 morphants. Overall, this data indicates that Cag Apo-14 is required for digestive system organogenesis during fish embryogenesis and larval development.

Interdependency between mechanical parameters and afferent nerve discharge in remodeled diabetic Goto-Kakizaki rat intestine.

PubMed

Zhao, Jingbo; Yang, Jian; Liao, Donghua; Gregersen, Hans

2017-01-01

Gastrointestinal disorders are very common in diabetic patients, but the pathogenesis is still not well understood. Peripheral afferent nerves may be involved due to the complex regulation of gastrointestinal function by the enteric nervous system. We aimed to characterize the stimulus-response function of afferent fibers innervating the jejunum in the Goto-Kakizaki (GK) type 2 diabetic rat model. A key question is whether changes in afferent firing arise from remodeled tissue or from adaptive afferent processes. Seven 32-week-old male GK rats and seven age-matched normal Wistar rats were studied. Firing from mesenteric afferent nerves was recorded in excised jejunal segments of seven GK rats and seven normal Wistar rats during ramp test, stress relaxation test, and creep test. The circumferential stress-strain, spike rate increase ratio (SRIR), and single unit firing rates were calculated for evaluation of interdependency of the mechanical stimulations and the afferent nerve discharge. Elevated sensitivity to mechanical stimuli was found for diabetic nerve bundles and single unit activity ( P <0.05). The stress relaxed less in the diabetic intestinal segment ( P <0.05). Linear association between SRIR and the thickness of circumferential muscle layer was found at high stress levels as well as for SRIR and the glucose level. Altered viscoelastic properties and elevated mechanosensitivity were found in the GK rat intestine. The altered nerve signaling is related to muscle layer remodeling and glucose levels and may contribute to gastrointestinal symptoms experienced by diabetic patients.

Muscle organizers in Drosophila: the role of persistent larval fibers in adult flight muscle development

NASA Technical Reports Server (NTRS)

Farrell, E. R.; Fernandes, J.; Keshishian, H.

1996-01-01

In many organisms muscle formation depends on specialized cells that prefigure the pattern of the musculature and serve as templates for myoblast organization and fusion. These include muscle pioneers in insects and muscle organizing cells in leech. In Drosophila, muscle founder cells have been proposed to play a similar role in organizing larval muscle development during embryogenesis. During metamorphosis in Drosophila, following histolysis of most of the larval musculature, there is a second round of myogenesis that gives rise to the adult muscles. It is not known whether muscle founder cells organize the development of these muscles. However, in the thorax specific larval muscle fibers do not histolyze at the onset of metamorphosis, but instead serve as templates for the formation of a subset of adult muscles, the dorsal longitudinal flight muscles (DLMs). Because these persistent larval muscle fibers appear to be functioning in many respects like muscle founder cells, we investigated whether they were necessary for DLM development by using a microbeam laser to ablate them singly and in combination. We found that, in the absence of the larval muscle fibers, DLMs nonetheless develop. Our results show that the persistent larval muscle fibers are not required to initiate myoblast fusion, to determine DLM identity, to locate the DLMs in the thorax, or to specify the total DLM fiber volume. However, they are required to regulate the number of DLM fibers generated. Thus, while the persistent larval muscle fibers are not obligatory for DLM fiber formation and differentiation, they are necessary to ensure the development of the correct number of fibers.

Functional genomics identifies regulators of the phototransduction machinery in the Drosophila larval eye and adult ocelli.

PubMed

Mishra, Abhishek Kumar; Bargmann, Bastiaan O R; Tsachaki, Maria; Fritsch, Cornelia; Sprecher, Simon G

2016-02-15

Sensory perception of light is mediated by specialized Photoreceptor neurons (PRs) in the eye. During development all PRs are genetically determined to express a specific Rhodopsin (Rh) gene and genes mediating a functional phototransduction pathway. While the genetic and molecular mechanisms of PR development is well described in the adult compound eye, it remains unclear how the expression of Rhodopsins and the phototransduction cascade is regulated in other visual organs in Drosophila, such as the larval eye and adult ocelli. Using transcriptome analysis of larval PR-subtypes and ocellar PRs we identify and study new regulators required during PR differentiation or necessary for the expression of specific signaling molecules of the functional phototransduction pathway. We found that the transcription factor Krüppel (Kr) is enriched in the larval eye and controls PR differentiation by promoting Rh5 and Rh6 expression. We also identified Camta, Lola, Dve and Hazy as key genes acting during ocellar PR differentiation. Further we show that these transcriptional regulators control gene expression of the phototransduction cascade in both larval eye and adult ocelli. Our results show that PR cell type-specific transcriptome profiling is a powerful tool to identify key transcriptional regulators involved during several aspects of PR development and differentiation. Our findings greatly contribute to the understanding of how combinatorial action of key transcriptional regulators control PR development and the regulation of a functional phototransduction pathway in both larval eye and adult ocelli. Copyright © 2015 Elsevier Inc. All rights reserved.

Convergent adaptive radiations in Madagascan and Asian ranid frogs reveal covariation between larval and adult traits

PubMed Central

Bossuyt, Franky; Milinkovitch, Michel C.

2000-01-01

Recent studies have reported that independent adaptive radiations can lead to identical ecomorphs. Our phylogenetic analyses of nuclear and mitochondrial DNA sequences here indicate that a major radiation of ranid frogs on Madagascar produced morphological, physiological, and developmental characters that are remarkably similar to those that independently evolved on the Indian subcontinent. We demonstrate further that, in several cases, adult and larval stages each evolved sets of characters which are not only convergent between independent lineages, but also allowed both developmental stages to invade the same adaptive zone. It is likely that such covariations are produced by similar selective pressures on independent larval and adult characters rather than by genetic or functional linkage. We briefly discuss why larval/adult covariations might constitute an important evolutionary phenomenon in species for which more than one developmental stage potentially has access to multiple environmental conditions. PMID:10841558

Is the Schwabe Organ a Retained Larval Eye? Anatomical and Behavioural Studies of a Novel Sense Organ in Adult Leptochiton asellus (Mollusca, Polyplacophora) Indicate Links to Larval Photoreceptors

PubMed Central

Sumner-Rooney, Lauren H.; Sigwart, Julia D.

2015-01-01

The discovery of a sensory organ, the Schwabe organ, was recently reported as a unifying feature of chitons in the order Lepidopleurida. It is a patch of pigmented tissue located on the roof of the pallial cavity, beneath the velum on either side of the mouth. The epithelium is densely innervated and contains two types of potential sensory cells. As the function of the Schwabe organ remains unknown, we have taken a cross-disciplinary approach, using anatomical, histological and behavioural techniques to understand it. In general, the pigmentation that characterises this sensory structure gradually fades after death; however, one particular concentrated pigment dot persists. This dot is positionally homologous to the larval eye in chiton trochophores, found in the same neuroanatomical location, and furthermore the metamorphic migration of the larval eye is ventral in species known to possess Schwabe organs. Here we report the presence of a discrete subsurface epithelial structure in the region of the Schwabe organ in Leptochiton asellus that histologically resembles the chiton larval eye. Behavioural experiments demonstrate that Leptochiton asellus with intact Schwabe organs actively avoid an upwelling light source, while Leptochiton asellus with surgically ablated Schwabe organs and a control species lacking the organ (members of the other extant order, Chitonida) do not (Kruskal-Wallis, H = 24.82, df = 3, p < 0.0001). We propose that the Schwabe organ represents the adult expression of the chiton larval eye, being retained and elaborated in adult lepidopleurans. PMID:26366861

Emergence flux declines disproportionately to larval density along a stream metals gradient

USGS Publications Warehouse

Schmidt, Travis S.; Kraus, Johanna M.; Walters, David M.; Wanty, Richard B.

2013-01-01

Effects of contaminants on adult aquatic insect emergence are less well understood than effects on insect larvae. We compared responses of larval density and adult emergence along a metal contamination gradient. Nonlinear threshold responses were generally observed for larvae and emergers. Larval densities decreased significantly at low metal concentrations but precipitously at concentrations of metal mixtures above aquatic life criteria (Cumulative Criterion Accumulation Ratio (CCAR) ≥ 1). In contrast, adult emergence declined precipitously at low metal concentrations (CCAR ≤ 1), followed by a modest decline above this threshold. Adult emergence was a more sensitive indicator of the effect of low metals concentrations on aquatic insect communities compared to larvae, presumably because emergence is limited by a combination of larval survival and other factors limiting successful emergence. Thus effects of exposure to larvae are not manifest until later in life (during metamorphosis and emergence). This loss in emergence reduces prey subsidies to riparian communities at concentrations considered safe for aquatic life. Our results also challenge the widely held assumption that adult emergence is a constant proportion of larval densities in all streams.

Interdependency between mechanical parameters and afferent nerve discharge in remodeled diabetic Goto-Kakizaki rat intestine

PubMed Central

Zhao, Jingbo; Yang, Jian; Liao, Donghua; Gregersen, Hans

2017-01-01

Background Gastrointestinal disorders are very common in diabetic patients, but the pathogenesis is still not well understood. Peripheral afferent nerves may be involved due to the complex regulation of gastrointestinal function by the enteric nervous system. Objective We aimed to characterize the stimulus–response function of afferent fibers innervating the jejunum in the Goto-Kakizaki (GK) type 2 diabetic rat model. A key question is whether changes in afferent firing arise from remodeled tissue or from adaptive afferent processes. Design Seven 32-week-old male GK rats and seven age-matched normal Wistar rats were studied. Firing from mesenteric afferent nerves was recorded in excised jejunal segments of seven GK rats and seven normal Wistar rats during ramp test, stress relaxation test, and creep test. The circumferential stress–strain, spike rate increase ratio (SRIR), and single unit firing rates were calculated for evaluation of interdependency of the mechanical stimulations and the afferent nerve discharge. Results Elevated sensitivity to mechanical stimuli was found for diabetic nerve bundles and single unit activity (P<0.05). The stress relaxed less in the diabetic intestinal segment (P<0.05). Linear association between SRIR and the thickness of circumferential muscle layer was found at high stress levels as well as for SRIR and the glucose level. Conclusion Altered viscoelastic properties and elevated mechanosensitivity were found in the GK rat intestine. The altered nerve signaling is related to muscle layer remodeling and glucose levels and may contribute to gastrointestinal symptoms experienced by diabetic patients. PMID:29238211

A Marriage Of Larval Modeling And Empirical Data: Linking Adult, Larval And Juvenile Scallops In An Estuary

NASA Astrophysics Data System (ADS)

Bayer, S.; Wahle, R.; Brooks, D. A.; Brady, D. C.

2016-02-01

The giant sea scallop, Placopecten magellanicus, is a commercially valuable sedentary broadcast spawner that occupies offshore banks and coastal bays and estuaries in the Northwest Atlantic. Although area closures have helped repopulate depleted scallop populations, little is known about whether populations at densities that yield larvae supply local or distant populations. Surveying scallop populations in the Damariscotta River estuary in Maine during the 2013 and 2014 spawning seasons, and settling out spat bags to collect settling larvae along the gradient of the estuary, we were able to compare adult densities to newly settled juvenile (`spat') abundance. Using the location where we found a high density of adults, we incorporated previously published behavior, pelagic larval duration, wind and current data into a particle dispersal model within the estuary to determine likely sinks for larvae from the 2013 and 2014 spawning seasons. Preliminary model simulations demonstrate where in the estuary swimming is effective in affecting water column position for larvae, and that most larvae are retained much closer to the mouth of the estuary than previously expected. Combining larval dispersal modeling with empirical data on adult densities and spat settlement on the scale of an embayment or estuary may be helpful in determining sources, sinks and areas that are both sources and sinks for shellfish species that are endangered or economically critical. This may aid in determining small area closures or Marine Protected Areas along coastal regions in the Gulf of Maine and beyond.

Larval diet affects mosquito development and permissiveness to Plasmodium infection.

PubMed

Linenberg, Inbar; Christophides, George K; Gendrin, Mathilde

2016-12-02

The larval stages of malaria vector mosquitoes develop in water pools, feeding mostly on microorganisms and environmental detritus. Richness in the nutrient supply to larvae influences the development and metabolism of larvae and adults. Here, we investigated the effects of larval diet on the development, microbiota content and permissiveness to Plasmodium of Anopheles coluzzii. We tested three fish diets often used to rear mosquitoes in the laboratory, including two pelleted diets, Dr. Clarke's Pool Pellets and Nishikoi Fish Pellets, and one flaked diet, Tetramin Fish-Flakes. Larvae grow and develop faster and produce bigger adults when feeding on both types of pellets compared with flakes. This correlates with a higher microbiota load in pellet-fed larvae, in agreement with the known positive effect of the microbiota on mosquito development. Larval diet also significantly influences the prevalence and intensity of Plasmodium berghei infection in adults, whereby Nishikoi Fish Pellets-fed larvae develop into adults that are highly permissive to parasites and survive longer after infection. This correlates with a lower amount of Enterobacteriaceae in the midgut microbiota. Together, our results shed light on the influence of larval feeding on mosquito development, microbiota and vector competence; they also provide useful data for mosquito rearing.

Larval Population Density Alters Adult Sleep in Wild-Type Drosophila melanogaster but Not in Amnesiac Mutant Flies

PubMed Central

Chi, Michael W.; Griffith, Leslie C.; Vecsey, Christopher G.

2014-01-01

Sleep has many important biological functions, but how sleep is regulated remains poorly understood. In humans, social isolation and other stressors early in life can disrupt adult sleep. In fruit flies housed at different population densities during early adulthood, social enrichment was shown to increase subsequent sleep, but it is unknown if population density during early development can also influence adult sleep. To answer this question, we maintained Drosophila larvae at a range of population densities throughout larval development, kept them isolated during early adulthood, and then tested their sleep patterns. Our findings reveal that flies that had been isolated as larvae had more fragmented sleep than those that had been raised at higher population densities. This effect was more prominent in females than in males. Larval population density did not affect sleep in female flies that were mutant for amnesiac, which has been shown to be required for normal memory consolidation, adult sleep regulation, and brain development. In contrast, larval population density effects on sleep persisted in female flies lacking the olfactory receptor or83b, suggesting that olfactory signals are not required for the effects of larval population density on adult sleep. These findings show that population density during early development can alter sleep behavior in adulthood, suggesting that genetic and/or structural changes are induced by this developmental manipulation that persist through metamorphosis. PMID:25116571

Larval Population Density Alters Adult Sleep in Wild-Type Drosophila melanogaster but Not in Amnesiac Mutant Flies.

PubMed

Chi, Michael W; Griffith, Leslie C; Vecsey, Christopher G

2014-08-11

Sleep has many important biological functions, but how sleep is regulated remains poorly understood. In humans, social isolation and other stressors early in life can disrupt adult sleep. In fruit flies housed at different population densities during early adulthood, social enrichment was shown to increase subsequent sleep, but it is unknown if population density during early development can also influence adult sleep. To answer this question, we maintained Drosophila larvae at a range of population densities throughout larval development, kept them isolated during early adulthood, and then tested their sleep patterns. Our findings reveal that flies that had been isolated as larvae had more fragmented sleep than those that had been raised at higher population densities. This effect was more prominent in females than in males. Larval population density did not affect sleep in female flies that were mutant for amnesiac, which has been shown to be required for normal memory consolidation, adult sleep regulation, and brain development. In contrast, larval population density effects on sleep persisted in female flies lacking the olfactory receptor or83b, suggesting that olfactory signals are not required for the effects of larval population density on adult sleep. These findings show that population density during early development can alter sleep behavior in adulthood, suggesting that genetic and/or structural changes are induced by this developmental manipulation that persist through metamorphosis.

Reverse osmosis and ultrafiltration for recovery and reuse of larval rearing water in Anopheles arabiensis mass production: Effect of water quality on larval development and fitness of emerging adults.

PubMed

Mamai, Wadaka; Hood-Nowotny, Rebecca; Maiga, Hamidou; Ali, Adel Barakat; Bimbile-Somda, Nanwintoun S; Soma, Diloma Dieudonné; Yamada, Hanano; Lees, Rosemary Susan; Gilles, Jeremie R L

2017-06-01

Countries around the world are showing increased interest in applying the sterile insect technique against mosquito disease vectors. Many countries in which mosquitoes are endemic, and so where vector control using the sterile insect technique may be considered, are located in arid zones where water provision can be costly or unreliable. Water reuse provides an alternate form of water supply. In order to reduce the cost of mass rearing of Anopheles arabiensis mosquitoes, the possibility of recycling and reusing larval rearing water was explored. The used rearing water ('dirty water') was collected after the tilting of rearing trays for collection of larvae/pupae, and larvae/pupae separation events and underwent treatment processes consisting of ultrafiltration and reverse osmosis. First-instar An. arabiensis larvae were randomly assigned to different water-type treatments, 500 larvae per laboratory rearing tray: 'clean' dechlorinated water, routinely used in rearing; dirty water; and 'recycled' dirty water treated using reverse osmosis and ultrafiltration. Several parameters of insect quality were then compared: larval development, pupation rate, adult emergence, body size and longevity. Water quality of the samples was analyzed in terms of ammonia, nitrite, nitrate, sulphate, dissolved oxygen, chloride, and phosphate concentrations after the larvae had all pupated or died. Surface water temperatures were also recorded continuously during larval development. Pupation rates and adult emergence were similar in all water treatments. Adult body sizes of larvae reared in recycled water were similar to those reared in clean water, but larger than those reared in the dirty larval water treatment, whereas the adult longevity of larvae reared in recycled water was significantly increased relative to both 'clean' and 'dirty' water. Dirty larval water contained significantly higher concentrations of ammonium, sulfate, phosphate and chloride and lower levels of dissolved

A Matrix Metalloproteinase Mediates Airway Remodeling in Drosophila

PubMed Central

Glasheen, Bernadette M.; Robbins, Renée M.; Piette, Caitlin; Beitel, Greg J.; Page-McCaw, Andrea

2010-01-01

Organ size typically increases dramatically during juvenile growth. This growth presents a fundamental tension, as organs need resiliency to resist stresses while still maintaining plasticity to accommodate growth. Extracellular matrix (ECM) is central to providing resiliency, but how ECM is remodeled to accommodate growth is poorly understood. We investigated remodeling of Drosophila respiratory tubes (tracheae) that elongate continually during larval growth, despite being lined with a rigid cuticular ECM. Cuticle is initially deposited with a characteristic pattern of repeating ridges and valleys known as taenidia. We find that for tubes to elongate, the extracellular protease Mmp1 is required for expansion of ECM between the taenidial ridges during each inter-molt period. Mmp1 protein localizes in periodically-spaced puncta that are in register with the taenidial spacing. Mmp1 also degrades old cuticle at molts, promotes apical membrane expansion in larval tracheae, and promotes tube elongation in embryonic tracheae. Whereas work in other developmental systems has demonstrated that MMPs are required for axial elongation occurring in localized growth zones, this study demonstrates that MMPs can also mediate interstitial matrix remodeling during growth of an organ system. PMID:20513443

Intestinal stem cells in the adult Drosophila midgut

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jiang, Huaqi, E-mail: Huaqi.Jiang@UTSouthwestern.edu; Edgar, Bruce A., E-mail: b.edgar@dkfz.de; Division of Basic Sciences, Fred Hutchinson Cancer Research Center, 1100 Fairview Ave. N., Seattle, WA 98109

Drosophila has long been an excellent model organism for studying stem cell biology. Notably, studies of Drosophila's germline stem cells have been instrumental in developing the stem cell niche concept. The recent discovery of somatic stem cells in adult Drosophila, particularly the intestinal stem cells (ISCs) of the midgut, has established Drosophila as an exciting model to study stem cell-mediated adult tissue homeostasis and regeneration. Here, we review the major signaling pathways that regulate the self-renewal, proliferation and differentiation of Drosophila ISCs, discussing how this regulation maintains midgut homeostasis and mediates regeneration of the intestinal epithelium after injury. -- Highlights:more » Black-Right-Pointing-Pointer The homeostasis and regeneration of adult fly midguts are mediated by ISCs. Black-Right-Pointing-Pointer Damaged enterocytes induce the proliferation of intestinal stem cells (ISC). Black-Right-Pointing-Pointer EGFR and Jak/Stat signalings mediate compensatory ISC proliferation. Black-Right-Pointing-Pointer Notch signaling regulates ISC self-renewal and differentiation.« less

Tissue-Specific Upregulation of MDS/EVI Gene Transcripts in the Intestine by Thyroid Hormone during Xenopus Metamorphosis

PubMed Central

Hasebe, Takashi; Fu, Liezhen; Heimeier, Rachel A.; Das, Biswajit; Ishizuya-Oka, Atsuko; Shi, Yun-Bo

2013-01-01

Background Intestinal remodeling during amphibian metamorphosis resembles the maturation of the adult intestine during mammalian postembryonic development when the adult epithelial self-renewing system is established under the influence of high concentrations of plasma thyroid hormone (T3). This process involves de novo formation and subsequent proliferation and differentiation of the adult stem cells. Methodology/Principal Findings The T3-dependence of the formation of adult intestinal stem cell during Xenopus laevis metamorphosis offers a unique opportunity to identify genes likely important for adult organ-specific stem cell development. We have cloned and characterized the ectopic viral integration site 1 (EVI) and its variant myelodysplastic syndrome 1 (MDS)/EVI generated via transcription from the upstream MDS promoter and alternative splicing. EVI and MDS/EVI have been implicated in a number of cancers including breast, leukemia, ovarian, and intestinal cancers. We show that EVI and MDS/EVI transcripts are upregulated by T3 in the epithelium but not the rest of the intestine in Xenopus laevis when adult stem cells are forming in the epithelium. Conclusions/Significance Our results suggest that EVI and MDS/EVI are likely involved in the development and/or proliferation of newly forming adult intestinal epithelial cells. PMID:23383234

Using remote sensing to map larval and adult populations of Anopheles hyrcanus (Diptera: Culicidae) a potential malaria vector in Southern France

PubMed Central

Tran, Annelise; Ponçon, Nicolas; Toty, Céline; Linard, Catherine; Guis, Hélène; Ferré, Jean-Baptiste; Lo Seen, Danny; Roger, François; de la Rocque, Stéphane; Fontenille, Didier; Baldet, Thierry

2008-01-01

Background Although malaria disappeared from southern France more than 60 years ago, suspicions of recent autochthonous transmission in the French Mediterranean coast support the idea that the area could still be subject to malaria transmission. The main potential vector of malaria in the Camargue area, the largest river delta in southern France, is the mosquito Anopheles hyrcanus (Diptera: Culicidae). In the context of recent climatic and landscape changes, the evaluation of the risk of emergence or re-emergence of such a major disease is of great importance in Europe. When assessing the risk of emergence of vector-borne diseases, it is crucial to be able to characterize the arthropod vector's spatial distribution. Given that remote sensing techniques can describe some of the environmental parameters which drive this distribution, satellite imagery or aerial photographs could be used for vector mapping. Results In this study, we propose a method to map larval and adult populations of An. hyrcanus based on environmental indices derived from high spatial resolution imagery. The analysis of the link between entomological field data on An. hyrcanus larvae and environmental indices (biotopes, distance to the nearest main productive breeding sites of this species i.e., rice fields) led to the definition of a larval index, defined as the probability of observing An. hyrcanus larvae in a given site at least once over a year. Independent accuracy assessments showed a good agreement between observed and predicted values (sensitivity and specificity of the logistic regression model being 0.76 and 0.78, respectively). An adult index was derived from the larval index by averaging the larval index within a buffer around the trap location. This index was highly correlated with observed adult abundance values (Pearson r = 0.97, p < 0.05). This allowed us to generate predictive maps of An. hyrcanus larval and adult populations from the landscape indices. Conclusion This work shows

[Carbohydrate restriction in the larval diet causes oxidative stress in adult insects of Drosophila melanogaster].

PubMed

Rovenko, B M; Lushchak, V I; Lushchak, O V

2013-01-01

The influence of 20 and 1% glucose and fructose, which were components of larval diet, on the level of oxidized proteins and lipids, low molecular mass antioxidant content as well as activities of antioxidant and associated enzymes in adult fruit fly Drosophila melanogaster were investigated. The restriction of carbohydrates in larval diet leads to oxidative stress in adult insects. It is supported by 40-50% increased content of protein carbonyl groups and by 60-70% decreased level of protein thiol groups as well as by a 4-fold increase of lipid peroxide content in 2-day-old flies of both sexes, developed on the diet with 1% carbohydrates. Oxidative stress, induced by carbohydrate restriction of the larval diet, caused the activation of antioxidant defence, differently exhibited in male and female fruit flies. Caloric restriction increased activity of superoxide dismutase and thioredoxin reductase associating only in males with 2-fold higher activity of NADPH-producing enzymes--glucose-6-phosphate dehydrogenase and isocitrate dehydrogenase. Carbohydrate restriction in the larval diet caused the increase of uric acid content, but the decrease in catalase activity in males. In females the values of these parameters were changed in opposite direction compared with males. The obtained results let us conclude the different involvement of low molecular mass antioxidants, glutathione and uric acid, and antioxidant enzyme catalase in the protection of male and female fruit fly macromolecules against oxidative damages, caused by calorie restriction of larval diet.

EVALUATION OF BIOACCUMULATION AND PHOTOINDUCED TOXICITY OF FLUORANTHENE IN LARVAL AND ADULT LIFE-STAGES OF CHIRONOMUS TENTANS

EPA Science Inventory

Laboratory sediment tests were conducted to evaluate the bioaccumulation and photoinduced toxicity of fluoranthene in larval and adult life-stages of Chironomus tentans. In the first of two experiments, fourth-instar and adult C. tentans exposed to spiked sediments were collected...

Nickel exposure alters behavioral parameters in larval and adult zebrafish.

PubMed

Nabinger, Débora Dreher; Altenhofen, Stefani; Bitencourt, Paula Eliete Rodrigues; Nery, Laura Roesler; Leite, Carlos Eduardo; Vianna, Mônica Ryff Moreira Roca; Bonan, Carla Denise

2018-05-15

Nickel is a heavy metal that, at high concentrations, leads to environmental contamination and causes health problems. We evaluated the effects of NiCl 2 exposure on cognition and behavior in larval and adult zebrafish. Larval and adult zebrafish were exposed to NiCl 2 concentrations (0.025, 2.0, 5.0, and 15.0mg/L) or water (control) in two treatment regimens: acute and subchronic. Larvae were exposed to NiCl 2 for 2h (acute treatment: 5-day-old larvae treated for 2h, tested after treatment) or 11days (subchronic treatment: 11-day-old larvae treated since fertilization, tested at 5, 8 and 11days post-fertilization, dpf). Adults were exposed for 12h (acute treatment) or 96h (subchronic treatment) and were tested after the treatment period. In both regimens, exposed zebrafish showed concentration-dependent increases in body nickel levels compared with controls. For larvae, delayed hatching, decreased heart rate and morphological alterations were observed in subchronically treated zebrafish. Larvae from subchronic treatment tested at 5dpf decrease distance and mean speed at a low concentration (0.025mg/L) and increased at higher concentrations (5.0 and 15.0mg/L). Subchronic treated larvae decrease locomotion at 15.0mg/L at 8 and 11dpf, whereas decreased escape responses to an aversive stimulus was observed at 2.0, 5.0 and 15.0mg/L in all developmental stages. For adults, the exploratory behavior test showed that subchronic nickel exposure induced anxiogenic-like behavior and decrease aggression, whereas impaired memory was observed in both treatments. These results indicate that exposure to nickel in early life stages of zebrafish leads to morphological alterations, avoidance response impairment and locomotor deficits whereas acute and subchronic exposure in adults resulst in anxiogenic effects, impaired memory and decreased aggressive behavior. These effects may be associated to neurotoxic actions of nickel and suggest this metal may influence animals' physiology in

Rhodopsin expression in the zebrafish pineal gland from larval to adult stage.

PubMed

Magnoli, Domenico; Zichichi, Rosalia; Laurà, Rosaria; Guerrera, Maria Cristina; Campo, Salvatore; de Carlos, Felix; Suárez, Alberto Álvarez; Abbate, Francesco; Ciriaco, Emilia; Vega, Jose Antonio; Germanà, Antonino

2012-03-09

The zebrafish pineal gland plays an important role in different physiological functions including the regulation of the circadian clock. In the fish pineal gland the pinealocytes are made up of different segments: outer segment, inner segment and basal pole. Particularly, in the outer segment the rhodopsin participates in the external environment light reception that represents the first biochemical step in the melatonin production. It is well known that the rhodopsin in the adult zebrafish is well expressed in the pineal gland but both the expression and the cellular localization of this protein during development remain still unclear. In this study using qRT-PCR, sequencing and immunohistochemistry the expression as well as the protein localization of the rhodopsin in the zebrafish from larval (10 dpf) to adult stage (90 dpf) were demonstrated. The rhodopsin mRNA expression presents a peak of expression at 10 dpf, a further reduction to 50 dpf before increasing again in the adult stage. Moreover, the cellular localization of the rhodopsin-like protein was always localized in the pinealocyte at all ages examined. Our results demonstrated the involvement of the rhodopsin in the zebrafish pineal gland physiology particularly in the light capture during the zebrafish lifespan. Copyright © 2012 Elsevier B.V. All rights reserved.

Effect of larval diet on cat flea (Siphonaptera: Pulicidae) developmental times and adult emergence.

PubMed

Moser, B A; Koehler, P G; Patterson, R S

1991-08-01

The natural diet of cat flea, Ctenocephalides felis (Bouche), larvae is primarily adult flea feces, but dried bovine blood may be substituted in the laboratory. Percentage adult emergence (79.4% on feces; 78.9% on blood) and developmental times (20.6 d on feces; 17.1 d on blood) did not significantly differ for the two diets. The drying temperature of blood determined its quality; blood dried at 120 degrees C was unsatisfactory for larval development. The dietary value of dried bovine blood was not enhanced when supplemented with brewer's yeast, rodent chow, or a combination of those constituents. Blood particle size ranging from less than 180 to greater than 500u did not affect the value of blood as a diet. Rodent chow, yeast, albumen, hemoglobin, and mixtures of these constituents were unsuitable as larval diets.

Diabetes-induced mechanophysiological changes in the small intestine and colon

PubMed Central

Zhao, Mirabella; Liao, Donghua; Zhao, Jingbo

2017-01-01

The disorders of gastrointestinal (GI) tract including intestine and colon are common in the patients with diabetes mellitus (DM). DM induced intestinal and colonic structural and biomechanical remodeling in animals and humans. The remodeling is closely related to motor-sensory abnormalities of the intestine and colon which are associated with the symptoms frequently encountered in patients with DM such as diarrhea and constipation. In this review, firstly we review DM-induced histomorphological and biomechanical remodeling of intestine and colon. Secondly we review motor-sensory dysfunction and how they relate to intestinal and colonic abnormalities. Finally the clinical consequences of DM-induced changes in the intestine and colon including diarrhea, constipation, gut microbiota change and colon cancer are discussed. The final goal is to increase the understanding of DM-induced changes in the gut and the subsequent clinical consequences in order to provide the clinicians with a better understanding of the GI disorders in diabetic patients and facilitates treatments tailored to these patients. PMID:28694926

Vulnerability and diet breadth predict larval and adult parasite diversity in fish of the Bothnian Bay.

PubMed

Locke, Sean A; Marcogliese, David J; Valtonen, E Tellervo

2014-01-01

Recent studies of aquatic food webs show that parasite diversity is concentrated in nodes that likely favour transmission. Various aspects of parasite diversity have been observed to be correlated with the trophic level, size, diet breadth, and vulnerability to predation of hosts. However, no study has attempted to distinguish among all four correlates, which may have differential importance for trophically transmitted parasites occurring as larvae or adults. We searched for factors that best predict the diversity of larval and adult endoparasites in 4105 fish in 25 species studied over a three-year period in the Bothnian Bay, Finland. Local predator-prey relationships were determined from stomach contents, parasites, and published data in 8,229 fish in 31 species and in seals and piscivorous birds. Fish that consumed more species of prey had more diverse trophically transmitted adult parasites. Larval parasite diversity increased with the diversity of both prey and predators, but increases in predator diversity had a greater effect. Prey diversity was more strongly associated with the diversity of adult parasites than with that of larvae. The proportion of parasite species present as larvae in a host species was correlated with the diversity of its predators. There was a notable lack of association with the diversity of any parasite guild and fish length, trophic level, or trophic category. Thus, diversity is associated with different nodal properties in larval and adult parasites, and association strengths also differ, strongly reflecting the life cycles of parasites and the food chains they follow to complete transmission.

Adolescent Alcohol Exposure: Burden of Epigenetic Reprogramming, Synaptic Remodeling, and Adult Psychopathology

PubMed Central

Kyzar, Evan J.; Floreani, Christina; Teppen, Tara L.; Pandey, Subhash C.

2016-01-01

Adolescence represents a crucial phase of synaptic maturation characterized by molecular changes in the developing brain that shape normal behavioral patterns. Epigenetic mechanisms play an important role in these neuromaturation processes. Perturbations of normal epigenetic programming during adolescence by ethanol can disrupt these molecular events, leading to synaptic remodeling and abnormal adult behaviors. Repeated exposure to binge levels of alcohol increases the risk for alcohol use disorder (AUD) and comorbid psychopathology including anxiety in adulthood. Recent studies in the field clearly suggest that adolescent alcohol exposure causes widespread and persistent changes in epigenetic, neurotrophic, and neuroimmune pathways in the brain. These changes are manifested by altered synaptic remodeling and neurogenesis in key brain regions leading to adult psychopathology such as anxiety and alcoholism. This review details the molecular mechanisms underlying adolescent alcohol exposure-induced changes in synaptic plasticity and the development of alcohol addiction-related phenotypes in adulthood. PMID:27303256

Larval food quantity affects development time, survival and adult biological traits that influence the vectorial capacity of Anopheles darlingi under laboratory conditions.

PubMed

Araújo, Maisa da-Silva; Gil, Luiz Herman S; e-Silva, Alexandre de-Almeida

2012-08-02

The incidence of malaria in the Amazon is seasonal and mosquito vectorial capacity parameters, including abundance and longevity, depend on quantitative and qualitative aspects of the larval diet. Anopheles darlingi is a major malaria vector in the Amazon, representing >95% of total Anopheles population present in the Porto Velho region. Despite its importance in the transmission of the Plasmodium parasite, knowledge of the larval biology and ecology is limited. Studies regarding aspects of adult population ecology are more common than studies on larval ecology. However, in order develop effective control strategies and laboratory breeding conditions for this species, more data on the factors affecting vector biology is needed. The aim of the present study is to assess the effects of larval food quantity on the vectorial capacity of An. darling under laboratory conditions. Anopheles darlingi was maintained at 28°C, 80% humidity and exposed to a daily photoperiod of 12 h. Larvae were divided into three experimental groups that were fed either a low, medium, or high food supply (based on the food amounts consumed by other species of culicids). Each experiment was replicated for six times. A cohort of adults were also exposed to each type of diet and assessed for several biological characteristics (e.g. longevity, bite frequency and survivorship), which were used to estimate the vectorial capacity of each experimental group. The group supplied with higher food amounts observed a reduction in development time while larval survival increased. In addition to enhanced longevity, increasing larval food quantity was positively correlated with increasing frequency of bites, longer blood meal duration and wing length, resulting in greater vectorial capacity. However, females had greater longevity than males despite having smaller wings. Overall, several larval and adult biological traits were significantly affected by larval food availability. Greater larval food supply

Neural circuit rewiring: insights from DD synapse remodeling.

PubMed

Kurup, Naina; Jin, Yishi

2016-01-01

Nervous systems exhibit many forms of neuronal plasticity during growth, learning and memory consolidation, as well as in response to injury. Such plasticity can occur across entire nervous systems as with the case of insect metamorphosis, in individual classes of neurons, or even at the level of a single neuron. A striking example of neuronal plasticity in C. elegans is the synaptic rewiring of the GABAergic Dorsal D-type motor neurons during larval development, termed DD remodeling. DD remodeling entails multi-step coordination to concurrently eliminate pre-existing synapses and form new synapses on different neurites, without changing the overall morphology of the neuron. This mini-review focuses on recent advances in understanding the cellular and molecular mechanisms driving DD remodeling.

Differential Transmission of HIV Traversing Fetal Oral/Intestinal Epithelia and Adult Oral Epithelia

PubMed Central

Herrera, Rossana; Veluppillai, Piri; Greenspan, Deborah; Soros, Vanessa; Greene, Warner C.; Levy, Jay A.; Palefsky, Joel M.

2012-01-01

While human immunodeficiency virus (HIV) transmission through the adult oral route is rare, mother-to-child transmission (MTCT) through the neonatal/infant oral and/or gastrointestinal route is common. To study the mechanisms of cell-free and cell-associated HIV transmission across adult oral and neonatal/infant oral/intestinal epithelia, we established ex vivo organ tissue model systems of adult and fetal origin. Given the similarity of neonatal and fetal oral epithelia with respect to epithelial stratification and density of HIV-susceptible immune cells, we used fetal oral the epithelium as a model for neonatal/infant oral epithelium. We found that cell-free HIV traversed fetal oral and intestinal epithelia and infected HIV-susceptible CD4+ T lymphocytes, Langerhans/dendritic cells, and macrophages. To study the penetration of cell-associated virus into fetal oral and intestinal epithelia, HIV-infected macrophages and lymphocytes were added to the surfaces of fetal oral and intestinal epithelia. HIV-infected macrophages, but not lymphocytes, transmigrated across fetal oral epithelia. HIV-infected macrophages and, to a lesser extent, lymphocytes transmigrated across fetal intestinal epithelia. In contrast to the fetal oral/intestinal epithelia, cell-free HIV transmigration through adult oral epithelia was inefficient and virions did not infect intraepithelial and subepithelial HIV-susceptible cells. In addition, HIV-infected macrophages and lymphocytes did not transmigrate through intact adult oral epithelia. Transmigration of cell-free and cell-associated HIV across the fetal oral/intestinal mucosal epithelium may serve as an initial mechanism for HIV MTCT. PMID:22205732

Features of liver tissue remodeling in intestinal failure during and after weaning off parenteral nutrition.

PubMed

Mutanen, Annika; Lohi, Jouko; Sorsa, Timo; Jalanko, Hannu; Pakarinen, Mikko P

2016-09-01

Intestinal failure is associated frequently with liver injury, which persists after weaning off parenteral nutrition. We compared features of liver remodeling in intestinal failure during and after weaning off parenteral nutrition. Liver biopsies and serum samples were obtained from 25 intestinal failure patients at a median age of 9.7 years (interquartile range: 4.6-18) and from age-matched control patients. Seven patients had been receiving parenteral nutrition for 53 months (22-160), and 18 patients had been weaned off parenteral nutrition 6.3 years (2.4-17) earlier, after having received parenteral nutrition for 10 months (3.3-34). Expression of alpha-smooth muscle actin, collagen 1, proinflammatory cytokines, growth factors, and matrix metalloproteinases (MMPs) was measured. Significant increases in immunohistochemical expression of alpha-smooth muscle actin and collagen 1 were observed predominantly in portal areas and were similar to increases seen in patients currently receiving parenteral nutrition and in patients weaned off parenteral nutrition. Gene and protein expressions of alpha-smooth muscle actin and collagen were interrelated. Gene expression of ACTA2, encoding alpha-smooth muscle actin, was increased only in patients who were receiving parenteral nutrition currently. Comparable upregulation of interleukin-1 (α and ß), epidermal growth factor, integrin-ß6, and MMP9 gene expression was observed in both patient groups, irrespective of whether they were receiving parenteral nutrition currently. Liver expression and serum levels of TIMP1 and MMP7 were increased only in the patients on parenteral nutrition currently but were not increased after weaning off parenteral nutrition. Intestinal failure is characterized by abnormal activation of hepatic myofibroblast and accumulation of collagen both during and after weaning off parenteral nutrition. Persistent transcriptional upregulation of proinflammatory and fibrogenic cytokines after weaning off

Phenoloxidase activity in larval and juvenile homogenates and adult plasma and haemocytes of bivalve molluscs.

PubMed

Luna-González, Antonio; Maeda-Martínez, Alfonso N; Vargas-Albores, Francisco; Ascencio-Valle, Felipe; Robles-Mungaray, Miguel

2003-10-01

Phenoloxidase (PO) activity was studied in larval and juvenile homogenates and in the plasma and haemocytes of adult Crassostrea gigas, Argopecten ventricosus, Nodipecten subnodosus, and Atrina maura. Samples were tested for the presence of PO activity by incubation with the substrate L-3, 4-dihydroxyphenylalanine using trypsin, alpha-chymotrypsin, laminarin, lipopolysaccharides (LPS), and sodium dodecyl sulphate (SDS) to elicit activation of prophenoloxidase (proPO) system. PO activity was not detected in larval homogenate. In juvenile homogenate, PO activity was found only in C. gigas and N. subnodosus. PO activity was present in adult samples and was enhanced by elicitors in the plasma of all species tested, but in haemocyte lysate supernatant (HLS) of only N. subnodosus. Activation of proPO by laminarin was suppressed by a protease inhibitor cocktail (P-2714) in plasma and HLS of all species tested.

In vivo transcriptional profile analysis reveals RNA splicing and chromatin remodeling as prominent processes for adult neurogenesis.

PubMed

Lim, Daniel A; Suárez-Fariñas, Mayte; Naef, Felix; Hacker, Coleen R; Menn, Benedicte; Takebayashi, Hirohide; Magnasco, Marcelo; Patil, Nila; Alvarez-Buylla, Arturo

2006-01-01

Neural stem cells and neurogenesis persist in the adult mammalian brain subventricular zone (SVZ). Cells born in the rodent SVZ migrate to the olfactory bulb (Ob) where they differentiate into interneurons. To determine the gene expression and functional profile of SVZ neurogenesis, we performed three complementary sets of transcriptional analysis experiments using Affymetrix GeneChips: (1) comparison of adult mouse SVZ and Ob gene expression profiles with those of the striatum, cerebral cortex, and hippocampus; (2) profiling of SVZ stem cells and ependyma isolated by fluorescent-activated cell sorting (FACS); and (3) analysis of gene expression changes during in vivo SVZ regeneration after anti-mitotic treatment. Gene Ontology (GO) analysis of data from these three separate approaches showed that in adult SVZ neurogenesis, RNA splicing and chromatin remodeling are biological processes as statistically significant as cell proliferation, transcription, and neurogenesis. In non-neurogenic brain regions, RNA splicing and chromatin remodeling were not prominent processes. Fourteen mRNA splicing factors including Sf3b1, Sfrs2, Lsm4, and Khdrbs1/Sam68 were detected along with 9 chromatin remodeling genes including Mll, Bmi1, Smarcad1, Baf53a, and Hat1. We validated the transcriptional profile data with Northern blot analysis and in situ hybridization. The data greatly expand the catalogue of cell cycle components, transcription factors, and migration genes for adult SVZ neurogenesis and reveal RNA splicing and chromatin remodeling as prominent biological processes for these germinal cells.

[Volvolus in an adult patient due to intestinal malrotation. Case report and review of literature].

PubMed

Nardone, Armando; Tamini, Nicolò; Nespoli, Luca; Pirovano, Riccardo

2010-01-01

Intestinal malrotation is a rare cause of bowel obstruction in adults and it could create a perplexing situation for surgeons not familiar with this pediatric pathology. Symptomatic patients present either acutely with bowel obstruction and intestinal ischemia with a midgut or cecal volvolus, or chronically with vague abdominal pain. Several modalities can be used to describe the intestinal abnormality such as barium X-ray, computer tomography scans, angiography and sometimes also the explorative laparotomy. The authors report on a case 62 years-old women presented to Emergency Center for plurime episodies of biliar emesis and diffuse abdominal pain in the last 5 days and treated for bowel obstruction secondary to a midgut volvolus in anomaly of fetal intestinal rotation.

Constant replenishment from circulating monocytes maintains the macrophage pool in adult intestine

PubMed Central

Scott, Charlotte L.; Perdiguero, Elisa Gomez; Geissmann, Frederic; Henri, Sandrine; Malissen, Bernard; Osborne, Lisa C.; Artis, David; Mowat, Allan McI.

2014-01-01

The paradigm that resident macrophages in steady-state tissues are derived from embryonic precursors has never been investigated in the intestine, which contains the largest pool of macrophages. Using fate mapping models and monocytopenic mice, together with bone marrow chimeric and parabiotic models, we show that embryonic precursors seeded the intestinal mucosa and demonstrated extensive in situ proliferation in the neonatal period. However these cells did not persist in adult intestine. Instead, they were replaced around the time of weaning by the CCR2-dependent influx of Ly6Chi monocytes that differentiated locally into mature, anti-inflammatory macrophages. This process was driven largely by the microbiota and had to be continued throughout adult life to maintain a normal intestinal macrophage pool. PMID:25151491

Sex-dependent effects of larval food stress on adult performance under semi-natural conditions: only a matter of size?

PubMed

Rosa, Elena; Saastamoinen, Marjo

2017-07-01

Organisms with complex life-cycles acquire essential nutrients as juveniles, and hence even a short-term food stress during development can impose serious fitness costs apparent in adults. We used the Glanville fritillary butterfly to investigate the effects of larval food stress on adult performance under semi-natural conditions in a population enclosure. We were specifically interested in whether the negative effects observed were due to body mass reduction only or whether additional effects unrelated to pupal mass were evident. The two sexes responded differently to the larval food stress. In females, larval food stress reduced pupal mass and reproductive performance. The reduced reproductive performance was partially mediated by pupal mass reduction. Food stressed females also had reduced within-patch mobility, and this effect was not dependent on pupal mass. Conversely, food stress had no effect on male pupal mass, suggesting a full compensation via prolonged development time. Nonetheless, food stressed males were less likely to sire any eggs, potentially due to changes in their territorial behavior, as indicated by food stress also increasing male within-patch mobility (i.e., patrolling behavior). When males did sire eggs, the offspring number and viability were unaffected by male food stress treatment. Viability was in general higher for offspring sired by lighter males. Our study highlights how compensatory mechanisms after larval food stress can act in a sex-specific manner and that the alteration in body mass is only partially responsible for the reduced adult performance observed.

Migration of Drosophila intestinal stem cells across organ boundaries

PubMed Central

Takashima, Shigeo; Paul, Manash; Aghajanian, Patrick; Younossi-Hartenstein, Amelia; Hartenstein, Volker

2013-01-01

All components of the Drosophila intestinal tract, including the endodermal midgut and ectodermal hindgut/Malpighian tubules, maintain populations of dividing stem cells. In the midgut and hindgut, these stem cells originate from within larger populations of intestinal progenitors that proliferate during the larval stage and form the adult intestine during metamorphosis. The origin of stem cells found in the excretory Malpighian tubules (‘renal stem cells’) has not been established. In this paper, we investigate the migration patterns of intestinal progenitors that take place during metamorphosis. Our data demonstrate that a subset of adult midgut progenitors (AMPs) move posteriorly to form the adult ureters and, consecutively, the renal stem cells. Inhibiting cell migration by AMP-directed expression of a dominant-negative form of Rac1 protein results in the absence of stem cells in the Malpighian tubules. As the majority of the hindgut progenitor cells migrate posteriorly and differentiate into hindgut enterocytes, a group of the progenitor cells, unexpectedly, invades anteriorly into the midgut territory. Consequently, these progenitor cells differentiate into midgut enterocytes. The midgut determinant GATAe is required for the differentiation of midgut enterocytes derived from hindgut progenitors. Wingless signaling acts to balance the proportion of hindgut progenitors that differentiate as midgut versus hindgut enterocytes. Our findings indicate that a stable boundary between midgut and hindgut/Malpighian tubules is not established during early embryonic development; instead, pluripotent progenitor populations cross in between these organs in both directions, and are able to adopt the fate of the organ in which they come to reside. PMID:23571215

Cdx function is required for maintenance of intestinal identity in the adult.

PubMed

Hryniuk, Alexa; Grainger, Stephanie; Savory, Joanne G A; Lohnes, David

2012-03-15

The homeodomain transcription factors Cdx1 and Cdx2 are expressed in the intestinal epithelium from early development, with expression persisting throughout the life of the animal. While our understanding of the function of Cdx members in intestinal development has advanced significantly, their roles in the adult intestine is relatively poorly understood. In the present study, we found that ablation of Cdx2 in the adult small intestine severely impacted villus morphology, proliferation and intestinal gene expression patterns, resulting in the demise of the animal. Long-term loss of Cdx2 in a chimeric model resulted in loss of all differentiated intestinal cell types and partial conversion of the mucosa to a gastric-like epithelium. Concomitant loss of Cdx1 did not exacerbate any of these phenotypes. Loss of Cdx2 in the colon was associated with a shift to a cecum-like epithelial morphology and gain of cecum-associated genes which was more pronounced with subsequent loss of Cdx1. These findings suggest that Cdx2 is essential for differentiation of the small intestinal epithelium, and that both Cdx1 and Cdx2 contribute to homeostasis of the colon. Copyright © 2012 Elsevier Inc. All rights reserved.

Effects of larval growth condition and water availability on desiccation resistance and its physiological basis in adult Anopheles gambiae sensu stricto

PubMed Central

2010-01-01

Background Natural populations of the malaria mosquito Anopheles gambiae s.s. are exposed to large seasonal and daily fluctuations in relative humidity and temperature, which makes coping with drought a crucial aspect of their ecology. Methods To better understand natural variation in desiccation resistance in this species, the effects of variation in larval food availability and access to water as an adult on subsequent phenotypic quality and desiccation resistance of adult females of the Mopti chromosomal form were tested experimentally. Results It was found that, under normal conditions, larval food availability and adult access to water had only small direct effects on female wet mass, dry mass, and water, glycogen and body lipid contents corrected for body size. In contrast, when females subsequently faced a strong desiccation challenge, larval food availability and adult access to water had strong carry-over effects on most measured physiological and metabolic parameters, and affected female survival. Glycogen and water content were the most used physiological reserves in relative terms, but their usage significantly depended on female phenotypic quality. Adult access to water significantly influenced the use of water and body lipid reserves, which subsequently affected desiccation resistance. Conclusions These results demonstrate the importance of growth conditions and water availability on adult physiological status and subsequent resistance to desiccation. PMID:20691104

Research on the traditional Chinese medicine treating gastrointestinal motility in diabetic rats by improving biomechanical remodeling and neuroendocrine regulation

PubMed Central

Tian, Jiaxing; Li, Min; Zhao, Jingbo; Li, Junling; Liu, Guifang; Zhen, Zhong; Cao, Yang; Gregersen, Hans; Tong, Xiaolin

2017-01-01

Previous studies have demonstrated that TWA, a Chinese herbal medicine, could significantly improve the symptoms of patients with diabetic gastrointestinal dysfunction. However, the specific mechanism of regulating intestinal peristalsis has not been found. This study aimed to discover TWA’s therapeutic mechanism for regulating intestinal motility. The intestinal propulsion rate of diabetic rats was significantly increased after treatment with TWA for 8 weeks. Aiming at the mechanical structure, biomechanical testing indicated that TWA can significantly decrease the no-load intestinal wall thickness, cross-sectional area, and angular spread in a zero-stress state. Notably, intestinal stress-strain curve shifted to the right, which indicated TWA can inhibit intestinal hyperplasia and hardening and improve biomechanical remodeling. Further study of the mechanism revealed that TWA significantly inhibited the expression of AGE in the villi, crypt, and muscle and RAGE in crypt and upregulated the expression of nerve regulator (PSD95, C-kit and SCF). Radioimmunoassay showed TWA treatment decreased levels of serum somatostatin and vasoactive intestinal peptide. Moreover, associations were found between the intestinal propulsion rate with the morphologic and biomechanical remodeling parameters, changes of nerve factors, and endocrine hormones. Morphologic and biomechanical remodeling of the intestinal wall are the pathologic basis of gastrointestinal dysfunction. TWA can benefit intestinal motility by improving biomechanical and morphologic remodeling and by regulating expression of neuroendocrine factors. The results showed that the effect of TWA was dose-dependent, the higher the dose, the greater is the improvement. Thus, traditional Chinese medicine might be a valuable tool for treating diabetic gastrointestinal dysfunction. PMID:28559973

Predictions of adult Anopheles albimanus densities in villages based on distances to remotely sensed larval habitats

NASA Technical Reports Server (NTRS)

Rejmankova, E.; Roberts, D. R.; Pawley, A.; Manguin, S.; Polanco, J.

1995-01-01

Remote sensing is particularly helpful for assessing the location and extent of vegetation formations, such as herbaceous wetlands, that are difficult to examine on the ground. Marshes that are sparsely populated with emergent macrophytes and dense cyanobacterial mats have previously been identified as very productive Anopheles albimanus larval habitats. This type of habitat was detectable on a classified multispectral System Probatoire d'Observation de la Terre image of northern Belize as a mixture of two isoclasses. A similar spectral signature is characteristic for vegetation of river margins consisting of aquatic grasses and water hyacinth, which constitutes another productive larval habitat. Based on the distance between human settlements (sites) of various sizes and the nearest marsh/river exhibiting this particular class combination, we selected two groups of sites: those located closer than 500 m and those located more than 1,500 m from such habitats. Based on previous adult collections near larval habitats, we defined a landing rate of 0.5 mosquitoes/human/min from 6:30 PM to 8:00 PM as the threshold for high (> or = 0.5 mosquitoes/human/min) versus low (< 0.5 mosquitoes/human/min) densities of An. albimanus. Sites located less than 500 m from the habitat were predicted as having values higher than this threshold, while lower values were predicted for sites located greater than 1,500 m from the habitat. Predictions were verified by collections of mosquitoes landing on humans. The predictions were 100% accurate for sites in the > 1,500-m category and 89% accurate for sites in the < 500-m category.

Report of a rare case and review of adult intestinal duplication at the opposite side of mesenteric margin.

PubMed

Huang, Zhi-Hao; Wan, Zi-Hao; Vikash, Vikash; Vikash, Sindhu; Jiang, Cong-Qing

2018-01-01

To study the previously discovered clinical entity of adult intestinal duplication and its treatment, and propose an extension to its existing classification. We report the case of an adult male with abdominal pain, constipation and vomiting. This patient underwent surgical separation of adhesions, reduction of torsion and intestinal decompression. Postoperative pathological findings confirmed the rare diagnosis of intestinal duplication. Adult intestinal duplication is quite rare. Its clinical manifestations are nonspecific. From this finding of intestinal duplication originating at the opposite side of the mesenteric margin, a further extension of the existing anatomical classification is proposed.

Molecular mechanism underlying juvenile hormone-mediated repression of precocious larval-adult metamorphosis.

PubMed

Kayukawa, Takumi; Jouraku, Akiya; Ito, Yuka; Shinoda, Tetsuro

2017-01-31

Juvenile hormone (JH) represses precocious metamorphosis of larval to pupal and adult transitions in holometabolous insects. The early JH-inducible gene Krüppel homolog 1 (Kr-h1) plays a key role in the repression of metamorphosis as a mediator of JH action. Previous studies demonstrated that Kr-h1 inhibits precocious larval-pupal transition in immature larva via direct transcriptional repression of the pupal specifier Broad-Complex (BR-C). JH was recently reported to repress the adult specifier gene Ecdysone-induced protein 93F (E93); however, its mechanism of action remains unclear. Here, we found that JH suppressed ecdysone-inducible E93 expression in the epidermis of the silkworm Bombyx mori and in a B. mori cell line. Reporter assays in the cell line revealed that the JH-dependent suppression was mediated by Kr-h1. Genome-wide ChIP-seq analysis identified a consensus Kr-h1 binding site (KBS, 14 bp) located in the E93 promoter region, and EMSA confirmed that Kr-h1 directly binds to the KBS. Moreover, we identified a C-terminal conserved domain in Kr-h1 essential for the transcriptional repression of E93 Based on these results, we propose a mechanism in which JH-inducible Kr-h1 directly binds to the KBS site upstream of the E93 locus to repress its transcription in a cell-autonomous manner, thereby preventing larva from bypassing the pupal stage and progressing to precocious adult development. These findings help to elucidate the molecular mechanisms regulating the metamorphic genetic network, including the functional significance of Kr-h1, BR-C, and E93 in holometabolous insect metamorphosis.

Storm drains as larval development and adult resting sites for Aedes aegypti and Aedes albopictus in Salvador, Brazil.

PubMed

Paploski, Igor Adolfo Dexheimer; Rodrigues, Moreno S; Mugabe, Vánio André; Kikuti, Mariana; Tavares, Aline S; Reis, Mitermayer Galvão; Kitron, Uriel; Ribeiro, Guilherme Sousa

2016-07-27

Dengue (DENV), Chikungunya (CHIKV), Zika (ZIKV), as well as yellow fever (YFV) viruses are transmitted to humans by Aedes spp. females. In Salvador, the largest urban center in north-eastern Brazil, the four DENV types have been circulating, and more recently, CHIKV and ZIKV have also become common. We studied the role of storm drains as Aedes larval development and adult resting sites in four neighbourhoods of Salvador, representing different socioeconomic, infrastructure and topographic conditions. A sample of 122 storm drains in the four study sites were surveyed twice during a 4-month period in 2015; in 49.0 % of the visits, the storm drains contained water. Adults and immatures of Aedes aegypti were captured in two of the four sites, and adults and immatures of Aedes albopictus were captured in one of these two sites. A total of 468 specimens were collected: 148 Ae. aegypti (38 adults and 110 immatures), 79 Ae. albopictus (48 adults and 31 immatures), and 241 non-Aedes (mainly Culex spp.) mosquitoes (42 adults and 199 immatures). The presence of adults or immatures of Ae. aegypti in storm drains was independently associated with the presence of non-Aedes mosquitoes and with rainfall of ≤ 50 mm during the preceding week. We found that in Salvador, one of the epicentres of the 2015 ZIKV outbreak, storm drains often accumulate water and serve as larval development sites and adult resting areas for both Ae. aegypti and Ae. albopictus. Vector control campaigns usually overlook storm drains, as most of the effort to prevent Ae. agypti reproduction is directed towards containers in the domicile environment. While further studies are needed to determine the added contribution of storm drains for the maintenance of Aedes spp. populations, we advocate that vector control programs incorporate actions directed at storm drains, including regular inspections and use of larvicides, and that human and capital resources are mobilized to modify storm drains, so that

Development, organization, and remodeling of phoronid muscles from embryo to metamorphosis (Lophotrochozoa: Phoronida).

PubMed

Temereva, Elena N; Tsitrin, Eugeni B

2013-04-24

The phoronid larva, which is called the actinotrocha, is one of the most remarkable planktotrophic larval types among marine invertebrates. Actinotrochs live in plankton for relatively long periods and undergo catastrophic metamorphosis, in which some parts of the larval body are consumed by the juvenile. The development and organization of the muscular system has never been described in detail for actinotrochs and for other stages in the phoronid life cycle. In Phoronopsis harmeri, muscular elements of the preoral lobe and the collar originate in the mid-gastrula stage from mesodermal cells, which have immigrated from the anterior wall of the archenteron. Muscles of the trunk originate from posterior mesoderm together with the trunk coelom. The organization of the muscular system in phoronid larvae of different species is very complex and consists of 14 groups of muscles. The telotroch constrictor, which holds the telotroch in the larval body during metamorphosis, is described for the first time. This unusual muscle is formed by apical myofilaments of the epidermal cells. Most larval muscles are formed by cells with cross-striated organization of myofibrils. During metamorphosis, most elements of the larval muscular system degenerate, but some of them remain and are integrated into the juvenile musculature. Early steps of phoronid myogenesis reflect the peculiarities of the actinotroch larva: the muscle of the preoral lobe is the first muscle to appear, and it is important for food capture. The larval muscular system is organized in differently in different phoronid larvae, but always exhibits a complexity that probably results from the long pelagic life, planktotrophy, and catastrophic metamorphosis. Degeneration of the larval muscular system during phoronid metamorphosis occurs in two ways, i.e., by complete or by incomplete destruction of larval muscular elements. The organization and remodeling of the muscular system in phoronids exhibits the combination of

Intestinal toxemia botulism in 3 adults, Ontario, Canada, 2006-2008.

PubMed

Sheppard, Yolanda D; Middleton, Dean; Whitfield, Yvonne; Tyndel, Felix; Haider, Shariq; Spiegelman, Jamie; Swartz, Richard H; Nelder, Mark P; Baker, Stacey L; Landry, Lisa; Maceachern, Ross; Deamond, Sherri; Ross, Lorrie; Peters, Garth; Baird, Michelle; Rose, David; Sanders, Greg; Austin, John W

2012-01-01

Five cases of intestinal toxemia botulism in adults were identified within an 18-month period in or near Toronto, Ontario, Canada. We describe findings for 3 of the 5 case-patients. Clinical samples contained Clostridium botulinum spores and botulinum neurotoxins (types A and B) for extended periods (range 41-61 days), indicative of intestinal toxemia botulism. Patients' clinical signs improved with supportive care and administration of botulinum antitoxin. Peanut butter from the residence of 1 case-patient yielded C. botulinum type A, which corresponded with type A spores found in the patient's feces. The food and clinical isolates from this case-patient could not be distinguished by pulsed-field gel electrophoresis. Two of the case-patients had Crohn disease and had undergone previous bowel surgery, which may have contributed to infection with C. botulinum. These cases reinforce the view that an underlying gastrointestinal condition is a risk factor for adult intestinal toxemia botulism.

Independent and interactive effects of immune activation and larval diet on adult immune function, growth and development in the greater wax moth (Galleria mellonella).

PubMed

Kangassalo, Katariina; Valtonen, Terhi M; Sorvari, Jouni; Kecko, Sanita; Pölkki, Mari; Krams, Indrikis; Krama, Tatjana; Rantala, Markus J

2018-06-29

Organisms in the wild are likely to face multiple immune challenges as well as additional ecological stressors, yet their interactive effects on immune function are poorly understood. Insects are found to respond to cues of increased infection risk by enhancing their immune capacity. However, such adaptive plasticity in immune function may be limited by physiological and environmental constraints. Here, we investigated the effects of two environmental stressors - poor larval diet and an artificial parasite-like immune challenge at the pupal stage - on adult immune function, growth and development in the greater wax moth (Galleria mellonella). Males whose immune system was activated with an artificial parasite-like immune challenge had weaker immune response - measured as strength of encapsulation response - as adults compared to the control groups, but only when raised in high-nutrition larval diet. Immune activation did not negatively affect adult immune response in males reared in low-nutrition larval diet, indicating that poor larval diet improved the capacity of the insects to respond to repeated immune challenges. Low-nutrition larval diet also had a positive independent effect on immune capacity in females, yet it negatively affected development time and adult body mass in both sexes. As in the nature immune challenges are rarely isolated, and adverse nutritional environment may indicate an elevated risk of infection, resilience to repeated immune challenges as a response to poor nutritional environment could provide a significant fitness advantage. The present study highlights the importance of considering environmental context when investigating effects of immune activation in insects. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

Experimental immunization of ponies with Strongylus vulgaris radiation-attenuated larvae or crude soluble somatic extracts from larval or adult stages.

PubMed

Monahan, C M; Taylor, H W; Chapman, M R; Klei, T R

1994-12-01

Protection from Strongylus vulgaris infection through immunization with radiation-attenuated third-stage larvae (L3) or crude soluble homogenates from larval or adult stages was examined. Yearling ponies raised parasite-free were divided into 3 immunization groups: radiation-attenuated L3; soluble adult somatic extracts; larval somatic extracts with excretory/secretory products (E/S) from in vitro culture; and 1 medium control group. Ponies were immunized twice; attenuated larvae were administered orally and somatic extracts or controls injected intramuscularly with adjuvant. Approximately 6 wk following the second immunization, all ponies were challenged. Necrospy examinations were performed 6 wk following challenge. Irradiated larvae recipients had the fewest postchallenge clinical signs and lesions and were 91% protected from infection determined by larval recoveries from arterial dissections. Soluble antigen recipients and controls had similar larval recoveries and thus equal susceptibility to challenge. Soluble antigen recipients had more severe clinical signs and lesions than controls, suggesting that parenteral immunization exacerbated postchallenge inflammatory responses. Protection by immunization with irradiated larvae was associated with an anamnestic eosinophilia and postimmunization antibody recognition of S. vulgaris L3 surface antigens. Histologic staining of eosinophils within tissues of this group suggested that this immunization induced a cytophilic antibody response that facilitated degranulation.

Terminalia Larval Host Fruit Reduces the Response of Bactrocera dorsalis (Diptera: Tephritidae) Adults to the Male Lure Methyl Eugenol.

PubMed

Manoukis, N C; Cha, D H; Collignon, R M; Shelly, T E

2018-04-12

Methyl eugenol (ME) is a powerful semiochemical attractant to males of the oriental fruit fly, Bactrocera dorsalis (Hendel) (Diptera: Tephritidae), and is the keystone of detection, control, and eradication programs against this polyphagous and highly invasive tephritid pest. Despite its status as a model lure against B. dorsalis, variation among individuals in their attraction is known, independent of the generally increasing attraction with age and decreases with previous exposure. Here we report that adult male B. dorsalis that fed on Terminalia catappa L. (Myrtales: Combretaceae) (tropical almond) fruit as larvae have a significantly lower behavioral response to ME compared with wild males from Psidium guajava L. (Myrtales: Myrtaceae) or colony-reared males raised on artificial larval diet. F1 males from the tropical almond stock reared on artificial larval diet did not show reduced attraction to ME, suggesting that the lowered response of parental males (sires) results from the host fruit itself, perhaps its relatively high amount of ME. Experiments with ME added to artificial diet lend some support to this interpretation. In addition to the results above, we report on quantities of ME in three different host fruits (T. catappa, P. guajava, and Carica papaya L. (Brassicales: Caricaceae)) of B. dorsalis. This study indicates the need for further research on the effect of host fruit on adult response to lures in economically important tephritids.

Adult zebrafish intestine resection: a novel model of short bowel syndrome, adaptation, and intestinal stem cell regeneration.

PubMed

Schall, K A; Holoyda, K A; Grant, C N; Levin, D E; Torres, E R; Maxwell, A; Pollack, H A; Moats, R A; Frey, M R; Darehzereshki, A; Al Alam, D; Lien, C; Grikscheit, T C

2015-08-01

Loss of significant intestinal length from congenital anomaly or disease may lead to short bowel syndrome (SBS); intestinal failure may be partially offset by a gain in epithelial surface area, termed adaptation. Current in vivo models of SBS are costly and technically challenging. Operative times and survival rates have slowed extension to transgenic models. We created a new reproducible in vivo model of SBS in zebrafish, a tractable vertebrate model, to facilitate investigation of the mechanisms of intestinal adaptation. Proximal intestinal diversion at segment 1 (S1, equivalent to jejunum) was performed in adult male zebrafish. SBS fish emptied distal intestinal contents via stoma as in the human disease. After 2 wk, S1 was dilated compared with controls and villus ridges had increased complexity, contributing to greater villus epithelial perimeter. The number of intervillus pockets, the intestinal stem cell zone of the zebrafish increased and contained a higher number of bromodeoxyuridine (BrdU)-labeled cells after 2 wk of SBS. Egf receptor and a subset of its ligands, also drivers of adaptation, were upregulated in SBS fish. Igf has been reported as a driver of intestinal adaptation in other animal models, and SBS fish exposed to a pharmacological inhibitor of the Igf receptor failed to demonstrate signs of intestinal adaptation, such as increased inner epithelial perimeter and BrdU incorporation. We describe a technically feasible model of human SBS in the zebrafish, a faster and less expensive tool to investigate intestinal stem cell plasticity as well as the mechanisms that drive intestinal adaptation. Copyright © 2015 the American Physiological Society.

Adult zebrafish intestine resection: a novel model of short bowel syndrome, adaptation, and intestinal stem cell regeneration

PubMed Central

Schall, K. A.; Holoyda, K. A.; Grant, C. N.; Levin, D. E.; Torres, E. R.; Maxwell, A.; Pollack, H. A.; Moats, R. A.; Frey, M. R.; Darehzereshki, A.; Al Alam, D.; Lien, C.

2015-01-01

Loss of significant intestinal length from congenital anomaly or disease may lead to short bowel syndrome (SBS); intestinal failure may be partially offset by a gain in epithelial surface area, termed adaptation. Current in vivo models of SBS are costly and technically challenging. Operative times and survival rates have slowed extension to transgenic models. We created a new reproducible in vivo model of SBS in zebrafish, a tractable vertebrate model, to facilitate investigation of the mechanisms of intestinal adaptation. Proximal intestinal diversion at segment 1 (S1, equivalent to jejunum) was performed in adult male zebrafish. SBS fish emptied distal intestinal contents via stoma as in the human disease. After 2 wk, S1 was dilated compared with controls and villus ridges had increased complexity, contributing to greater villus epithelial perimeter. The number of intervillus pockets, the intestinal stem cell zone of the zebrafish increased and contained a higher number of bromodeoxyuridine (BrdU)-labeled cells after 2 wk of SBS. Egf receptor and a subset of its ligands, also drivers of adaptation, were upregulated in SBS fish. Igf has been reported as a driver of intestinal adaptation in other animal models, and SBS fish exposed to a pharmacological inhibitor of the Igf receptor failed to demonstrate signs of intestinal adaptation, such as increased inner epithelial perimeter and BrdU incorporation. We describe a technically feasible model of human SBS in the zebrafish, a faster and less expensive tool to investigate intestinal stem cell plasticity as well as the mechanisms that drive intestinal adaptation. PMID:26089336

Posttransplant complications in adult recipients of intestine grafts without bowel decontamination.

PubMed

Clouse, Jared W; Kubal, Chandrashekhar A; Fridell, Jonathan A; Mangus, Richard S

2018-05-01

Selective digestive decontamination is commonly used to decrease lumenal bacterial flora. Preoperative bowel decontamination may be associated with a lower wound infection rate but has not been shown to decrease risk of intra-abdominal abscess or lower leak rate for enteric anastomoses. Alternatively, the decontamination disrupts the normal flora of the gastrointestinal tract and may affect normal physiology, including immunologic function. This study reports complication rates of an intestine transplant program that has never used bowel decontamination. All adult patients who underwent intestine transplant from 2003 to 2015 at a single center were reviewed. Posttransplant complications included intra-abdominal abscess, enteric fistula, and leak from the enteric anastomosis. Viral, fungal, and bacterial infections in the first year after transplant are reported. There were 184 adult patients who underwent deceased donor intestine transplant during the study period. Among these patients, 30% developed an infected postoperative fluid collection, 4 developed an enteric fistula (2%), and 16 had an enteric or anastomotic leak (8%). The rate of any bacterial infection was 91% in the first year, with a wound infection rate of 25%. Fungal infection occurred in 47% of patients. Rejection rates were 55% at 1 y for isolated intestine patients and 17% for multivisceral (liver inclusive) patients. Among this population of intestine transplant patients in which no bowel decontamination was used, rates of surgical complications, infections, and rejection were similar to those reported by other centers. Bowel decontamination provides no identifiable benefit in intestine transplantation. Copyright © 2018 Elsevier Inc. All rights reserved.

The Chromatin Remodeler BPTF Activates a Stemness Gene-Expression Program Essential for the Maintenance of Adult Hematopoietic Stem Cells.

PubMed

Xu, Bowen; Cai, Ling; Butler, Jason M; Chen, Dongliang; Lu, Xiongdong; Allison, David F; Lu, Rui; Rafii, Shahin; Parker, Joel S; Zheng, Deyou; Wang, Gang Greg

2018-03-13

Self-renewal and differentiation of adult stem cells are tightly regulated partly through configuration of chromatin structure by chromatin remodelers. Using knockout mice, we here demonstrate that bromodomain PHD finger transcription factor (BPTF), a component of the nucleosome remodeling factor (NURF) chromatin-remodeling complex, is essential for maintaining the population size of hematopoietic stem/progenitor cells (HSPCs), including long-term hematopoietic stem cells (HSCs). Bptf-deficient HSCs are defective in reconstituted hematopoiesis, and hematopoietic-specific knockout of Bptf caused profound defects including bone marrow failure and anemia. Genome-wide transcriptome profiling revealed that BPTF loss caused downregulation of HSC-specific gene-expression programs, which contain several master transcription factors (Meis1, Pbx1, Mn1, and Lmo2) required for HSC maintenance and self-renewal. Furthermore, we show that BPTF potentiates the chromatin accessibility of key HSC "stemness" genes. These results demonstrate an essential requirement of the chromatin remodeler BPTF and NURF for activation of "stemness" gene-expression programs and proper function of adult HSCs. Copyright © 2018 The Author(s). Published by Elsevier Inc. All rights reserved.

Comparative studies on intestine ultrastructure of third-stage larvae and adults of Cystidicoloides ephemeridarum (Nematoda, Cystidicolidae).

PubMed

Frantová, Denisa; Moravec, Frantisek

2004-11-01

The intestinal epithelium of third-stage larvae and adults of Cystidicoloides ephemeridarum from haemocoel of mayflies and stomach of brown trout was studied by electron microscopy and cytochemistry. In section, the intestine of both stages is composed of a single layer of about ten undifferentiated intestinal cells in a ring. A labyrinth of deep invaginations is present in the basal region of each cell. The apical surface is modified into well developed, regularly arranged microvilli. These, together with numerous organelles engaged in metabolism and a well defined gut lumen filled with unidentifiable material suggest that the intestine may function in digestion and absorption during both stages. The adults seem to feed upon the semifluid content of the stomach of brown trout. Fortuitous oral infection with undetermined bacteria in vitro led to degenerative changes in the intestinal tissue and probably caused death of the infected specimens. Up to 75% of the cell volume in the L(3) is occupied by glycogen deposits. In the adults, a minor portion of glycogen, together with lipid droplets, has been observed. The adults are considered to rely more on aerobic metabolism, whereas anaerobic metabolism (glycolysis) may prevail in L(3).

Development, organization, and remodeling of phoronid muscles from embryo to metamorphosis (Lophotrochozoa: Phoronida)

PubMed Central

2013-01-01

Background The phoronid larva, which is called the actinotrocha, is one of the most remarkable planktotrophic larval types among marine invertebrates. Actinotrochs live in plankton for relatively long periods and undergo catastrophic metamorphosis, in which some parts of the larval body are consumed by the juvenile. The development and organization of the muscular system has never been described in detail for actinotrochs and for other stages in the phoronid life cycle. Results In Phoronopsis harmeri, muscular elements of the preoral lobe and the collar originate in the mid-gastrula stage from mesodermal cells, which have immigrated from the anterior wall of the archenteron. Muscles of the trunk originate from posterior mesoderm together with the trunk coelom. The organization of the muscular system in phoronid larvae of different species is very complex and consists of 14 groups of muscles. The telotroch constrictor, which holds the telotroch in the larval body during metamorphosis, is described for the first time. This unusual muscle is formed by apical myofilaments of the epidermal cells. Most larval muscles are formed by cells with cross-striated organization of myofibrils. During metamorphosis, most elements of the larval muscular system degenerate, but some of them remain and are integrated into the juvenile musculature. Conclusion Early steps of phoronid myogenesis reflect the peculiarities of the actinotroch larva: the muscle of the preoral lobe is the first muscle to appear, and it is important for food capture. The larval muscular system is organized in differently in different phoronid larvae, but always exhibits a complexity that probably results from the long pelagic life, planktotrophy, and catastrophic metamorphosis. Degeneration of the larval muscular system during phoronid metamorphosis occurs in two ways, i.e., by complete or by incomplete destruction of larval muscular elements. The organization and remodeling of the muscular system in phoronids

Achieving Optimal Post-Exercise Muscle Protein Remodeling in Physically Active Adults through Whole Food Consumption

PubMed Central

van Vliet, Stephan; Beals, Joseph W.; Martinez, Isabel G.; Skinner, Sarah K.; Burd, Nicholas A.

2018-01-01

Dietary protein ingestion is critical to maintaining the quality and quantity of skeletal muscle mass throughout adult life. The performance of acute exercise enhances muscle protein remodeling by stimulating protein synthesis rates for several hours after each bout, which can be optimized by consuming protein during the post-exercise recovery period. To date, the majority of the evidence regarding protein intake to optimize post-exercise muscle protein synthesis rates is limited to isolated protein sources. However, it is more common to ingest whole food sources of protein within a normal eating pattern. Emerging evidence demonstrates a promising role for the ingestion of whole foods as an effective nutritional strategy to support muscle protein remodeling and recovery after exercise. This review aims to evaluate the efficacy of the ingestion of nutrient-rich and protein-dense whole foods to support post-exercise muscle protein remodeling and recovery with pertinence towards physically active people. PMID:29462924

Preweaning modulation of intestinal microbiota by oligosaccharides or amoxicillin can contribute to programming of adult microbiota in rats.

PubMed

Morel, Fanny B; Oozeer, Raish; Piloquet, Hugues; Moyon, Thomas; Pagniez, Anthony; Knol, Jan; Darmaun, Dominique; Michel, Catherine

2015-03-01

Increasing evidence suggests that early nutrition has programming effects on adult health. Identifying mechanisms underlying nutritional programming would aid in the design of new disease prevention strategies. The intestinal microbiota could be a key player in this programming because it affects host metabolic homeostasis, postnatal gut colonization is sensitive to early nutrition, and initial microbial set-up is thought to shape microbiota composition for life. The aim of this study was to determine whether early manipulation of intestinal microbiota actually programs adult microbiota in rats. Suckling rats pups were supplemented with fructo-oligosaccharides, galacto-oligosaccharides/long-chain fructan mix (GOS/lcF, 9/1), acidic oligosaccharides, amoxicillin, or vehicle from the fifth to the fourteenth day of life, and weaned to standard chow at day 21. Ceco-colonic microbiota was characterized at 14 and 131 d by real-time polymerase chain reaction analysis. At day 14, all treatments affected microbiota. Amoxicillin had the most significant effect. All oligosaccharides decreased Firmicutes levels, whereas only fructo-oligosaccharides and GOS/lcF increased bifidobacteria. At day 131, most of these effects had faded away but a significant, albeit minor, adult microbiota programming was observed for rats that received GOS/lcF mix before weaning, regarding Roseburia intestinalis cluster, one subdivision of the Erysipelotrichaceae family as well as butyrate kinase gene. As revealed by a targeted quantitative polymerase chain reaction approach, programming of adult intestinal microbiota seems to vary according to the nature of the preweaning microbiotal modulator. This suggests that intestinal microbiota may, only under specific circumstances, serve as a relay of neonatal nutrition and thus potentially contribute to nutritional programming of host physiology. Copyright © 2015 Elsevier Inc. All rights reserved.

Ontogenetic improvement of visual function in the medaka Oryzias latipes based on an optomotor testing system for larval and adult fish

USGS Publications Warehouse

Carvalho, Paulo S. M.; Noltie, Douglas B.; Tillitt, D.E.

2002-01-01

We developed a system for evaluation of visual function in larval and adult fish. Both optomotor (swimming) and optokinetic (eye movement) responses were monitored and recorded using a system of rotating stripes. The system allowed manipulation of factors such as width of the stripes used, rotation speed of the striped drum, and light illuminance levels within both the scotopic and photopic ranges. Precise control of these factors allowed quantitative measurements of visual acuity and motion detection. Using this apparatus, we tested the hypothesis that significant posthatch ontogenetic improvements in visual function occur in the medaka Oryzias latipes, and also that this species shows significant in ovo neuronal development. Significant improvements in the acuity angle alpha (ability to discriminate detail) were observed from approximately 5 degrees at hatch to 1 degree in the oldest adult stages. In addition, we measured a significant improvement in flicker fusion thresholds (motion detection skills) between larval and adult life stages within both the scotopic and photopic ranges of light illuminance. Ranges of flicker fusion thresholds (X±SD) at log I=1.96 (photopic) varied from 37.2±1.6 cycles/s in young adults to 18.6±1.6 cycles/s in young larvae 10 days posthatch. At log I=−2.54 (scotopic), flicker fusion thresholds varied from 5.8±0.7 cycles/s in young adults to 1.7±0.4 cycles/s in young larvae 10 days posthatch. Light sensitivity increased approximately 2.9 log units from early hatched larval stages to adults. The demonstrated ontogenetic improvements in visual function probably enable the fish to explore new resources, thereby enlarging their fundamental niche.

VESGEN Mapping of Bioactive Protection against Intestinal Inflammation: Application to Human Spaceflight and ISS Experiments

NASA Technical Reports Server (NTRS)

Parsons-Wingerter, P. A.; Chen, X.; Kelly, C. P.; Reinecker, H. C.

2011-01-01

Challenges to successful space exploration and colonization include adverse physiological reactions to micro gravity and space radiation factors. Constant remodeling of the microvasculature is critical for tissue preservation, wound healing, and recovery after ischemia. Regulation of the vascular system in the intestine is particularly important to enable nutrient absorption while maintaining barrier function and mucosal defense against micro biota. Although tremendous progress has been made in understanding the molecular circuits regulating neovascularization, our knowledge of the adaptations of the vascular system to environmental challenges in the intestine remains incomplete. This is in part because of the lack of methods to observe and quantify the complex processes associated with vascular responses in vivo. Developed by GRC as a mature beta version, pre-release research software, VESsel GENeration Analysis (VESGEN) maps and quantifies the fractal-based complexity of vascular branching for novel insights into the cytokine, transgenic and therapeutic regulation of angiogenesis, lymphangiogenesis and microvascular remodeling. Here we demonstrate that VESGEN can be used to characterize the dynamic vascular responses to acute intestinal inflammation and mucosal recovery from in vivo confocal microscopic 3D image series. We induced transient intestinal inflammation in mice by DSS treatment and investigated whether the ability of the pro biotic yeast Saccharomyces boulardii (Sb) to protect against intestinal inflammation was due to regulation of vascular remodeling. A primary characteristic of inflammation is excessive neovascularization (angiogenesis) resulting in fragile vessels prone to bleeding. Morphological parameters for triplicate specimens revealed that Sb treatment greatly reduced the inflammatory response of vascular networks by an average of 78%. This resulted from Sb inhibition of vascular endothelial growth factor receptor signaling, a major

Transmission of Salmonella to broilers by contaminated larval and adult lesser mealworms, Alphitobius diaperinus (Coleoptera: Tenebrionidae).

PubMed

Roche, A J; Cox, N A; Richardson, L J; Buhr, R J; Cason, J A; Fairchild, B D; Hinkle, N C

2009-01-01

The ability of the lesser mealworm, Alphitobius diaperinus (Panzer), commonly known as the darkling beetle, to transmit marker Salmonella Typhimurium to day-of-hatch broiler chicks was evaluated, as well as the spread to nonchallenged pen mates. In trial 1, day-of-hatch chicks were orally gavaged with 4 larval or 4 adult beetles that had been exposed to marker Salmonella-inoculated feed for 72 h. In addition, chicks were gavaged with the marker Salmonella in saline solution. These chicks were then placed into pens to serve as challenged broilers. In trial 2, all pens received 2 challenged chicks that were gavaged with larvae or beetles that had been exposed to marker Salmonella-inoculated feed for 24 h and then removed from the inoculated feed for a period of 7 d. At 3 wk of age, cecal samples from the marker Salmonella-challenged broilers and from 5 pen mates in trial 1, or 10 pen mates in trial 2, were evaluated for the presence of the marker Salmonella in their ceca, and at 6 wk of age, all remaining pen mates were sampled. To monitor the presence of the marker Salmonella within pens, stepped-on drag swab litter samples were taken weekly. For the Salmonella-saline pens, 29 to 33% of the broilers that had been challenged and 10 to 55% of the pen mates were positive at 3 wk of age, and only 2 to 6% had positive ceca at 6 wk. For the pens challenged with adult beetles, 0 to 57% of the challenged broilers and 20 to 40% of the pen mates had positive ceca at 3 wk, and 4 to 7% were positive at 6 wk. The pens challenged with larvae had the greatest percentage of marker Salmonella-positive broilers; 25 to 33% of the challenged broilers and 45 to 58% of pen mates were positive at 3 wk, and 11 to 27% were positive at 6 wk. These results demonstrated that ingestion of larval or adult beetles contaminated with a marker Salmonella could be a significant vector for transmission to broilers.

Annexin 2-caveolin 1 complex is a target of ezetimibe and regulates intestinal cholesterol transport.

PubMed

Smart, Eric J; De Rose, Robert A; Farber, Steven A

2004-03-09

Modulation of cholesterol absorption in the intestine, the primary site of dietary cholesterol uptake in humans, can have profound clinical implications. We have undertaken a reverse genetic approach by disrupting putative cholesterol processing genes in zebrafish larvae by using morpholino (MO) antisense oligonucleotides. By using targeted MO injections and immunoprecipitation (IP) experiments coupled with mass spectrometry, we determined that annexin (ANX)2 complexes with caveolin (CAV)1 in the zebrafish and mouse intestine. The complex is heat stable and unaffected by SDS or reducing conditions. MO targeting of anx2b or cav1, which are both strongly expressed in the larval and adult zebrafish intestinal epithelium, prevents formation of the protein heterocomplex. Furthermore, anx2b MO injection prevents processing of a fluorescent cholesterol reporter and results in reduced sterol mass. Pharmacological treatment of mice with ezetimibe disrupts the heterocomplex in only hypercholesterolemic animals. These data suggest that ANX2 and CAV1 are components of an intestinal sterol transport complex.

What does not kill them makes them stronger: larval environment and infectious dose alter mosquito potential to transmit filarial worms.

PubMed

Breaux, Jennifer A; Schumacher, Molly K; Juliano, Steven A

2014-07-07

For organisms with complex life cycles, larval environments can modify adult phenotypes. For mosquitoes and other vectors, when physiological impacts of stressors acting on larvae carry over into the adult stage they may interact with infectious dose of a vector-borne pathogen, producing a range of phenotypes for vector potential. Investigation of impacts of a common source of stress, larval crowding and intraspecific competition, on adult vector interactions with pathogens may increase our understanding of the dynamics of pathogen transmission by mosquito vectors. Using Aedes aegypti and the nematode parasite Brugia pahangi, we demonstrate dose dependency of fitness effects of B. pahangi infection on the mosquito, as well as interactions between competitive stress among larvae and infectious dose for resulting adults that affect the physiological and functional ability of mosquitoes to act as vectors. Contrary to results from studies on mosquito-arbovirus interactions, our results suggest that adults from crowded larvae may limit infection better than do adults from uncrowded controls, and that mosquitoes from high-quality larval environments are more physiologically and functionally capable vectors of B. pahangi. Our results provide another example of how the larval environment can have profound effects on vector potential of resulting adults. © 2014 The Author(s) Published by the Royal Society. All rights reserved.

Soundscapes and Larval Settlement: Larval Bivalve Responses to Habitat-Associated Underwater Sounds.

PubMed

Eggleston, David B; Lillis, Ashlee; Bohnenstiehl, DelWayne R

2016-01-01

We quantified the effects of habitat-associated sounds on the settlement response of two species of bivalves with contrasting habitat preferences: (1) Crassostrea virginicia (oyster), which prefers to settle on other oysters, and (2) Mercenaria mercenaria (clam), which settles on unstructured habitats. Oyster larval settlement in the laboratory was significantly higher when exposed to oyster reef sound compared with either off-reef or no-sound treatments. Clam larval settlement did not vary according to sound treatments. Similar to laboratory results, field experiments showed that oyster larval settlement in "larval housings" suspended above oyster reefs was significantly higher compared with off-reef sites.

Correlations between adult mimicry and larval host plants in ithomiine butterflies.

PubMed

Willmott, Keith R; Mallet, James

2004-08-07

The apparent paradox of multiple coexisting wing pattern mimicry 'rings' in tropical butterflies has been explained as a result of microhabitat partitioning in adults. However, very few studies have tested this hypothesis. In neotropical forests, ithomiine butterflies dominate and display the richest diversity of mimicry rings. We show that co-mimetic species occupy the same larval host-plant species significantly more often than expected in two out of five communities that we surveyed; in one of these, the effect remains significant after phylogenetic correction. This relationship is most probably a result of a third correlated variable, such as microhabitat. Host-plant microhabitat may constrain adult movement, or host-plant choice may depend on butterfly microhabitat preferences and mimicry associations. This link between mimicry and host plant could help explain some host-plant and mimicry shifts, which have been important in the radiation of this speciose tropical group.

Swimming behavior of larval Medaka fish under microgravity

NASA Astrophysics Data System (ADS)

Furukawa, R.; Ijiri, K.

Fish exhibit looping and rolling behaviors when subjected to short periods of microgravity during parabolic flight. Strain-differences in the behavioral response of adult Medaka fish ( Oryzias latipes) were reported previously, however, there have been few studies of larval fish behavior under microgravity. In the present study, we investigated whether microgravity affects the swimming behavior of larvae at various ages (0 to 20 days after hatching), using different strains: HNI-II, HO5, ha strain, and variety of different strains (variety). The preliminary experiments were done in the ground laboratory: the development of eyesight was examined using optokinetic response for the different strains. The visual acuity of larvae improved drastically during 20 days after hatching. Strain differences of response were noted for the development of their visual acuity. In microgravity, the results were significantly different from those of adult Medaka. The larval fish appeared to maintain their orientation, except that a few of them exhibited looping and rolling behavior. Further, most larvae swam normally with their backs turning toward the light source (dorsal light response, DLR), and the rest of them stayed with their abdomen touching the surface of the container (ventral substrate response, VSR). For larval stages, strain-differences and age-differences in behavior were observed, but less pronounced than with adult fish under microgravity. Our observations suggest that adaptability of larval fish to the gravitational change and the mechanism of their postural control in microgravity are more variable than in adult fish.

Explaining variation in adult Anopheles indoor resting abundance: the relative effects of larval habitat proximity and insecticide-treated bed net use.

PubMed

McCann, Robert S; Messina, Joseph P; MacFarlane, David W; Bayoh, M Nabie; Gimnig, John E; Giorgi, Emanuele; Walker, Edward D

2017-07-17

Spatial determinants of malaria risk within communities are associated with heterogeneity of exposure to vector mosquitoes. The abundance of adult malaria vectors inside people's houses, where most transmission takes place, should be associated with several factors: proximity of houses to larval habitats, structural characteristics of houses, indoor use of vector control tools containing insecticides, and human behavioural and environmental factors in and near houses. While most previous studies have assessed the association of larval habitat proximity in landscapes with relatively low densities of larval habitats, in this study these relationships were analysed in a region of rural, lowland western Kenya with high larval habitat density. 525 houses were sampled for indoor-resting mosquitoes across an 8 by 8 km study area using the pyrethrum spray catch method. A predictive model of larval habitat location in this landscape, previously verified, provided derivations of indices of larval habitat proximity to houses. Using geostatistical regression models, the association of larval habitat proximity, long-lasting insecticidal nets (LLIN) use, house structural characteristics (wall type, roof type), and peridomestic variables (cooking in the house, cattle near the house, number of people sleeping in the house) with mosquito abundance in houses was quantified. Vector abundance was low (mean, 1.1 adult Anopheles per house). Proximity of larval habitats was a strong predictor of Anopheles abundance. Houses without an LLIN had more female Anopheles gambiae s.s., Anopheles arabiensis and Anopheles funestus than houses where some people used an LLIN (rate ratios, 95% CI 0.87, 0.85-0.89; 0.84, 0.82-0.86; 0.38, 0.37-0.40) and houses where everyone used an LLIN (RR, 95% CI 0.49, 0.48-0.50; 0.39, 0.39-0.40; 0.60, 0.58-0.61). Cooking in the house also reduced Anopheles abundance across all species. The number of people sleeping in the house, presence of cattle near the house

Remodelling the extracellular matrix in development and disease

PubMed Central

Bonnans, Caroline; Chou, Jonathan; Werb, Zena

2015-01-01

The extracellular matrix (ECM) is a highly dynamic structure that is present in all tissues and continuously undergoes controlled remodelling. This process involves quantitative and qualitative changes in the ECM, mediated by specific enzymes that are responsible for ECM degradation, such as metalloproteinases. The ECM interacts with cells to regulate diverse functions, including proliferation, migration and differentiation. ECM remodelling is crucial for regulating the morphogenesis of the intestine and lungs, as well as of the mammary and submandibular glands. Dysregulation of ECM composition, structure, stiffness and abundance contributes to several pathological conditions, such as fibrosis and invasive cancer. A better understanding of how the ECM regulates organ structure and function and of how ECM remodelling affects disease progression will contribute to the development of new therapeutics. PMID:25415508

Pheromone modulates two phenotypically plastic traits - adult reproduction and larval diapause - in the nematode Caenorhabditis elegans.

PubMed

Wharam, Barney; Weldon, Laura; Viney, Mark

2017-08-22

Animals use information from their environment to make decisions, ultimately to maximize their fitness. The nematode C. elegans has a pheromone signalling system, which hitherto has principally been thought to be used by worms in deciding whether or not to arrest their development as larvae. Recent studies have suggested that this pheromone can have other roles in the C. elegans life cycle. Here we demonstrate a new role for the C. elegans pheromone, showing that it accelerates hermaphrodites' reproductive rate, a phenomenon which we call pheromone-dependent reproductive plasticity (PDRP). We also find that pheromone accelerates larval growth rates, but this depends on a live bacterial food source, while PDRP does not. Different C. elegans strains all show PDRP, though the magnitude of these effects differ among the strains, which is analogous to the diversity of arrested larval phenotypes that this pheromone also induces. Using a selection experiment we also show that selection for PDRP or for larval arrest affects both the target and the non-target trait, suggesting that there is cross-talk between these two pheromone-dependent traits. Together, these results show that C. elegans' pheromone is a signal that acts at two key life cycle points, controlling alternative larval fates and affecting adult hermaphrodites' reproduction. More broadly, these results suggest that to properly understand and interpret the biology of pheromone signalling in C. elegans and other nematodes, the life-history biology of these organisms in their natural environment needs to be considered.

Interspecific larval competition between invasive Aedes japonicus and native Aedes triseriatus (Diptera: Culicidae) and adult longevity.

PubMed

Alto, Barry W

2011-03-01

The Asian rock pool mosquito Aedes japonicus (Theobald) inhabits natural and artificial container habitats, some of which are occupied by the native treehole mosquitoAedes triseriatus (Say), a vector of LaCrosse encephalitis virus. A laboratory experiment was used to evaluate the effects of nutrient limitation and interspecific interactions between these species. The goal was to address two related hypotheses. First, interspecific interactions between these species show competitive asymmetry with the invasive mosquito Ae. japonicus being favored over Ae. triseriatus. Second, competitive stress at the larval stage alters adult longevity. There was minimal evidence for competitive asymmetry between these two species. Mosquito and population performance showed clear negative density-dependent effects with similar effects of intra- and interspecific interactions. Only Ae. japonicus development time showed competitive asymmetry over Ae. triseriatus, providing weak support for the first hypothesis. For both species, competition resulted in lower adult longevity compared with low competition, providing support for the second hypothesis. These results suggest both species are similarly affected by intra- and interspecific competition and underscore the importance of the effects of larval competition that continue into adulthood and alter parameters important to transmission of vector-borne diseases.

[Adult transient intestinal intussusception: can abdominal CT guide resolution?].

PubMed

Stabile Ianora, Amato Antonio; Telegrafo, Michele; Lorusso, Valentina; Rella, Leonarda; Niccoli Asabella, Artor; La Porta, Michele; Moschetta, Marco

2013-01-01

The purpose of this study was to evaluate the adult transient intestinal intussusceptions on CT before and after the administration of gastrointestinal contrast material. We evaluated two different gastrointestinal contrast materials: hyperdense and hypodense. In all cases the gastrointestinal contrast agent solved the invaginations. In the group of patients treated with hypodense contrast medium relapses occurred in the short and long term; no recurrence was observed in the other group. CT is useful in the recognition of intestinal intussusception. The gastrointestinal contrast agent could define the real transience of intussusceptions and hyperdense contrast agent could be more effective in short and long term resolution.

Effects of Low Salinity on Adult Behavior and Larval Performance in the Intertidal Gastropod Crepipatella peruviana (Calyptraeidae)

PubMed Central

Montory, Jaime A.; Pechenik, Jan A.; Diederich, Casey M.; Chaparro, Oscar R.

2014-01-01

Shallow-water coastal areas suffer frequent reductions in salinity due to heavy rains, potentially stressing the organisms found there, particularly the early stages of development (including pelagic larvae). Individual adults and newly hatched larvae of the gastropod Crepipatella peruviana were exposed to different levels of salinity stress (32(control), 25, 20 or 15), to quantify the immediate effects of exposure to low salinities on adult and larval behavior and on the physiological performance of the larvae. For adults we recorded the threshold salinity that initiates brood chamber isolation. For larvae, we measured the impact of reduced salinity on velar surface area, velum activity, swimming velocity, clearance rate (CR), oxygen consumption (OCR), and mortality (LC50); we also documented the impact of salinity discontinuities on the vertical distribution of veliger larvae in the water column. The results indicate that adults will completely isolate themselves from the external environment by clamping firmly against the substrate at salinities ≤24. Moreover, the newly hatched larvae showed increased mortality at lower salinities, while survivors showed decreased velum activity, decreased exposed velum surface area, and decreased mean swimming velocity. The clearance rates and oxygen consumption rates of stressed larvae were significantly lower than those of control individuals. Finally, salinity discontinuities affected the vertical distribution of larvae in the water column. Although adults can protect their embryos from low salinity stress until hatching, salinities <24 clearly affect survival, physiology and behavior in early larval life, which will substantially affect the fitness of the species under declining ambient salinities. PMID:25077484

The Remodeling Process: A Grounded Theory Study of Perceptions of Treatment among Adult Male Incest Offenders.

ERIC Educational Resources Information Center

Scheela, Rochelle A.

1992-01-01

Conducted grounded theory study to explore incest offender perceptions of treatment to generate explanatory theory of sexual abuse treatment process. Findings from theoretical sampling of 20 adult male incest offenders revealed that offenders felt remodeling process occurred as they faced discovery of their abuse and went through treatment.…

[Intestinal microecology of the adult population of Mongolia, Switzerland, and Russia].

PubMed

Korshunov, V M; Potashnik, L V; Efimov, B A; Korshunova, O V; Smeianov, V V; Gyr, K; Frei, R; Ierendorzh, D

2001-01-01

The study of intestinal microflora was made in clinically healthy young adults living in rural areas of Mongolia, in Russia (Moscow) and in Switzerland, as well as in Swiss citizens of elderly age groups (55-68 and 87-94 years). Essential differences in the quantitative and qualitative characteristics of intestinal microflora both in the inhabitants of different countries as well as in people belonging to different age groups in the same country were established. The results of the study demonstrated the expediency of working out the criteria of the norm for intestinal microflora both for the population of different countries and for people living in the same country, but belonging to different age groups.

Exploration of the "larval pool": development and ground-truthing of a larval transport model off leeward Hawai'i.

PubMed

Wren, Johanna L K; Kobayashi, Donald R

2016-01-01

Most adult reef fish show site fidelity thus dispersal is limited to the mobile larval stage of the fish, and effective management of such species requires an understanding of the patterns of larval dispersal. In this study, we assess larval reef fish distributions in the waters west of the Big Island of Hawai'i using both in situ and model data. Catches from Cobb midwater trawls off west Hawai'i show that reef fish larvae are most numerous in offshore waters deeper than 3,000 m and consist largely of pre-settlement Pomacanthids, Acanthurids and Chaetodontids. Utilizing a Lagrangian larval dispersal model, we were able to replicate the observed shore fish distributions from the trawl data and we identified the 100 m depth strata as the most likely depth of occupancy. Additionally, our model showed that for larval shore fish with a pelagic larval duration longer than 40 days there was no significant change in settlement success in our model. By creating a general additive model (GAM) incorporating lunar phase and angle we were able to explain 67.5% of the variance between modeled and in situ Acanthurid abundances. We took steps towards creating a predictive larval distribution model that will greatly aid in understanding the spatiotemporal nature of the larval pool in west Hawai'i, and the dispersal of larvae throughout the Hawaiian archipelago.

Life-table analysis of Anopheles arabiensis in western Kenya highlands: effects of land covers on larval and adult survivorship.

PubMed

Afrane, Yaw A; Zhou, Goufa; Lawson, Bernard W; Githeko, Andrew K; Yan, Guiyun

2007-10-01

In high-elevation areas in western Kenya, the abundance of Anopheles arabiensis is either very low or absent. The western Kenya highlands (an area with an elevation > 1,500m above sea level) have also been experiencing extensive deforestation, and deforestation has been suggested as one of the important factors that facilitate malaria transmission in the highlands. This study investigated whether climate conditions in the western Kenya highlands (Kakamega, elevation 1,500 m above sea level) were permissive to the development and survival of An. arabiensis and whether deforestation promoted An. arabiensis survivorship of immature and adult stages, using life-table analysis. We found that in larval habitats located in forested areas, only 4-9% of first-instar larvae developed into adults and the development length exceeded 20 days. Mean water temperature of aquatic habitats in the deforested area was 4.8-6.1 degrees C higher than that in the forested area, larval-to-adult survivorship was increased to 65-82%, and larval-to-adult development time was shortened by 8-9 days. The average indoor temperature in houses in the deforested area was 1.7-1.8 degrees C higher than in the forested area, and the relative humidity was 22-25% lower. The median survival time of adult mosquitoes in the deforested area was 49-55% higher than those in the forested area. The net reproductive rate of female mosquitoes in the deforested area was 1.7- to 2.6-fold higher than that in the forested area. Compared with previously published data on An. gambiae, the net reproductive rate of An. arabiensis was only 0.8-1.3% of Anopheles gambiae in the forested area and 2.3-2.6% in the deforested area. Therefore, the current ambient climate condition is less permissive to An. arabiensis than to An. gambiae in western Kenya highlands. However, environmental changes such as deforestation and global warming may facilitate the establishment of An. arabiensis populations in the highlands.

Utilizing mass spectrometry imaging to map the thyroid hormones triiodothyronine and thyroxine in Xenopus tropicalis tadpoles.

PubMed

Goto-Inoue, Naoko; Sato, Tomohiko; Morisasa, Mizuki; Kashiwagi, Akihiko; Kashiwagi, Keiko; Sugiura, Yuki; Sugiyama, Eiji; Suematsu, Makoto; Mori, Tsukasa

2018-02-01

Thyroid hormones are not only responsible for thermogenesis and energy metabolism in animals, but also have an important role in cell differentiation and development. Amphibian metamorphosis provides an excellent model for studying the remodeling of the body. This metamorphic organ remodeling is induced by thyroid hormones, and a larval body is thus converted into an adult one. The matrix-assisted laser desorption/ionization (MALDI)-mass spectrometry (MS) imaging technology is expected to be a suitable tool for investigating small bioreactive molecules. The present study describes the distribution of the thyroid hormones, i.e., triiodothyronine (T3) and thyroxine (T4) and their inactive form reverse T3 (rT3) in Xenopus tropicalis tadpoles using two different types of imaging techniques, MS/MS and Fourier transform (FT)-MS imaging. As a result of MS/MS imaging, we demonstrated that T3 was mainly distributed in the gills. T4 was faintly localized in the eyes, inner gills, and intestine during metamorphosis. The intensity of T3 in the gills and the intensity of T4 in the body fluids were increased during metamorphosis. Moreover, the localization of the inactive form rT3 was demonstrated to be separate from T3, namely in the intestine and muscles. In addition, FT-MS imaging could utilize simultaneous imaging including thyroid hormone. This is the first report to demonstrate the molecular distribution of thyroid hormones themselves and to discriminate T3, T4, and rT3 in animal tissues.

Phormidium animalis (Cyanobacteria: Oscillatoriaceae) supports larval development of Anopheles albimanus.

PubMed

Vázquez-Martínez, M Guadalupe; Rodríguez, Mario H; Arredondo-Jiménez, Juan I; Méndez-Sánchez, José D

2003-06-01

The capability of Phormidium animalis, a cyanobacterium commonly found in larval habitats of Anopheles albimanus in southern Mexico, to support larval development of this mosquito was investigated. First-stage larvae were reared under insectary conditions with P. animalis ad libitum and their development was compared with larvae fed with wheat germ. The time of pupation and adult mosquito size, assessed by wing length, were similar in both groups, but fewer adult mosquitoes were obtained from larvae fed with the cyanobacteria. Nevertheless, these observations indicate that P. animalis is ingested and assimilated by larval An. albimanus, making this cyanobacterium a good candidate for genetic engineering for the introduction of mosquitocidal toxins for malaria control in the region.

In vitro effects of aqueous extract from Maytenus senegalensis (Lam.) Exell stem bark on egg hatching, larval migration and adult worms of Haemonchus contortus.

PubMed

Zangueu, Calvin Bogning; Olounlade, Abiodoun Pascal; Ossokomack, Marlyse; Djouatsa, Yolande Noelle Nangue; Alowanou, Goue Géorcelin; Azebaze, Anatole Guy Blaise; Llorent-Martínez, Eulogio José; de Córdova, Maria Luisa Fernández; Dongmo, Alain Bertrand; Hounzangbe-Adote, Mawulé Sylvie

2018-05-02

Maytenus senegalensis is a common shrub which is scattered in tropical Africa. Different parts of this plant have been reported to be useful in traditional medicine against gastrointestinal disorders and intestinal worms. This study evaluated the anthelmintic activity of the aqueous stem bark extract of M. senegalensis using egg hatch assay (EHA), larval migration inhibition assay (LMIA) and adult worms' motility inhibition assay (AMIA). On EHA, the extract concentrations tested resulted in a significant (p < 0.01) inhibition of egg hatching in concentration-dependent manner and ranged between 31.86% at 75 μg.mL - 1 to 54.92% at 2400 μg.mL - 1 after a 48 h post-exposure with eggs. For the LMI assays, the aqueous extract of M. senegalensis showed a significant (p < 0.05) inhibition of larval migration in a concentration-dependent manner. The highest concentration used (2400 μg.mL - 1 ) showed a 37.77% inhibition. The use of polyvinyl polypyrrolidone (PVPP) indicated that tannins and flavonoids were partly involved in the effect since the larval migration was inhibited by 15.5%, but other biochemical compounds were also implicated. On AMIA, M. senegalensis was associated with a reduced worm motility after a 24 h post exposure compared to phosphate buffered saline as control (p < 0.05). By this time 66.66% of the worms' were found immotile or dead in the wells containing plant extract at 2400 μg.mL - 1 . The Phytochemical analysis of aqueous extract of M. senegalensis by HPLC-ESI-MS n detected the presence of proanthocyanidins (20%) and flavonoids (> 50%). These in vitro results suggest the presence of some anthelmintic properties in M. senegalensis extract, which is traditionally used by small farmers in west and central Africa. These effects may be due to the flavonoids and proanthocyanidins present in the extract and need to be studied under in vivo conditions.

Microanatomy of the intestinal lymphatic system

PubMed Central

Miller, Mark J.; Newberry, Rodney D.

2011-01-01

The intestinal lymphatic system is comprised of two non-communicating lymphatic networks; one containing the lacteals draining the villi and the connecting submucosal lymphatic network, and one containing the lymphatics that drain the intestine muscular layer. These systems deliver lymph into a common network of collecting lymphatics originating near the mesenteric border. The intestinal lymphatic system serves vital functions in the regulation of tissue fluid homeostasis, immune surveillance, and the transport of nutrients, and conversely this system is affected by, and directly contributes to, disease processes within the intestine. Recent discoveries of specific lymphatic markers, factors promoting lymphangiogenesis, and factors selectively affecting the development of intestinal lymphatics hold promise for unlocking the role of lymphatics in the pathogenesis of diseases affecting the intestine and for intestinal lymphatic selective therapies. Vital to progress in understanding how the intestinal lymphatic system functions is integrating of recent advances identifying molecular pathways for lymphatic growth and remodeling with advanced imaging modalities to observe lymphatic function and dysfunction in vivo. PMID:20961303

Neonate intestinal immune response to CpG oligodeoxynucleotide stimulation.

PubMed

Lacroix-Lamandé, Sonia; Rochereau, Nicolas; Mancassola, Roselyne; Barrier, Mathieu; Clauzon, Amandine; Laurent, Fabrice

2009-12-14

The development of mucosal vaccines is crucial to efficiently control infectious agents for which mucosae are the primary site of entry. Major drawbacks of these protective strategies are the lack of effective mucosal adjuvant. Synthetic oligodeoxynucleotides that contain several unmethylated cytosine-guanine dinucleotide (CpG-ODN) motifs are now recognized as promising adjuvants displaying mucosal adjuvant activity through direct activation of TLR9-expressing cells. However, little is known about the efficacy of these molecules in stimulating the intestinal immune system in neonates. First, newborn mice received CpG-ODN orally, and the intestinal cytokine and chemokine response was measured. We observed that oral administration of CpG-ODN induces CXC and CC chemokine responses and a cellular infiltration in the intestine of neonates as detected by immunohistochemistry. We next compared the efficiency of the oral route to intraperitoneal administration in stimulating the intestinal immune responses of both adults and neonates. Neonates were more responsive to TLR9-stimulation than adults whatever the CpG-ODN administration route. Their intestinal epithelial cells (IECs) indirectly responded to TLR9 stimulation and contributed to the CXC chemokine response, whereas other TLR9-bearing cells of the lamina-propria produced CC chemokines and Th1-type cytokines. Moreover, we showed that the intestine of adult exhibited a significantly higher level of IL10 at homeostasis than neonates, which might be responsible for the unresponsiveness to TLR9-stimulation, as confirmed by our findings in IL10-deficient mice. This is the first report that deciphers the role played by CpG-ODN in the intestine of neonates. This work clearly demonstrates that an intraperitoneal administration of CpG-ODN is more efficient in neonates than in adults to stimulate an intestinal chemokine response due to their lower IL-10 intestinal level. In addition we report the efficiency of the oral route at

Efficiency of two larval diets for mass-rearing of the mosquito Aedes aegypti

PubMed Central

Bond, J. G.; Ramírez-Osorio, A.; Marina, C. F.; Fernández-Salas, I.; Liedo, P.; Dor, A.

2017-01-01

Aedes aegypti is a major vector of arboviruses that may be controlled on an area-wide basis using the sterile insect technique (SIT). Larval diet is a major factor in mass-rearing for SIT programs. We compared dietary effects on immature development and adult fitness-related characteristics for an International Atomic Energy Agency (IAEA) diet, developed for rearing Ae. albopictus, and a standardized laboratory rodent diet (LRD), under a 14:10 h (light:dark) photoperiod ("light" treatment) or continuous darkness during larval rearing. Larval development was generally fastest in the IAEA diet, likely reflecting the high protein and lipid content of this diet. The proportion of larvae that survived to pupation or to adult emergence did not differ significantly between diets or light treatments. Insects from the LRD-dark treatment produced the highest proportion of male pupae (93% at 24 h after the beginning of pupation) whereas adult sex ratio from the IAEA diet tended to be more male-biased than that of the LRD diet. Adult longevity did not differ significantly with larval diet or light conditions, irrespective of sex. In other aspects the LRD diet generally performed best. Adult males from the LRD diet were significantly larger than those from the IAEA diet, irrespective of light treatment. Females from the LRD diet had ~25% higher fecundity and ~8% higher egg fertility compared to those from the IAEA diet. Adult flight ability did not differ between larval diets, and males had a similar number of copulations with wild females, irrespective of larval diet. The LRD diet had lower protein and fat content but a higher carbohydrate and energetic content than the IAEA diet. We conclude that the LRD diet is a low-cost standardized diet that is likely to be suitable for mass-rearing of Ae. aegypti for area-wide SIT-based vector control. PMID:29095933

Insecticide Resistance and Metabolic Mechanisms Involved in Larval and Adult Stages of Aedes aegypti Insecticide-Resistant Reference Strains from Cuba.

PubMed

Bisset, Juan Andrés; Rodríguez, María Magdalena; French, Leydis; Severson, David W; Gutiérrez, Gladys; Hurtado, Daymi; Fuentes, Ilario

2014-12-01

Studies were conducted to compare levels of insecticide resistance and to determine the metabolic resistance mechanisms in larval and adult stages of Aedes aegypti from Cuba. Three insecticide-resistant reference strains of Ae. aegypti from Cuba were examined. These strains were derived from a Santiago de Cuba strain isolated in 1997; it was previously subjected to a strong selection for resistance to temephos (SAN-F6), deltamethrin (SAN-F12), and propoxur (SAN-F13) and routinely maintained in the laboratory under selection pressure up to the present time, when the study was carried out. In addition, an insecticide-susceptible strain was used for comparison. The insecticide resistance in larvae and adults was determined using standard World Health Organization methodologies. Insecticide resistance mechanisms were determined by biochemical assays. The esterases (α EST and β EST) and mixed function oxidase (MFO) activities were significantly higher in adults than in the larvae of the three resistant strains studied. The association of resistance level with the biochemical mechanism for each insecticide was established for each stage. The observed differences between larval and adult stages of Ae. aegypti in their levels of insecticide resistance and the biochemical mechanisms involved should be included as part of monitoring and surveillance activities in Ae. aegypti vector control programs.

Trade-offs between larval survival and adult ornament development depend on predator regime in a territorial dragonfly.

PubMed

Moore, Michael P; Martin, Ryan A

2018-05-28

Trade-offs between juvenile survival and the development of sexually selected traits can cause ontogenetic conflict between life stages that constrains adaptive evolution. However, the potential for ecological interactions to alter the presence or strength of these trade-offs remains largely unexplored. Antagonistic selection over the accumulation and storage of resources could be one common cause of environment-specific trade-offs between life stages: higher condition may simultaneously enhance adult ornament development and increase juvenile vulnerability to predators. We tested this hypothesis in an ornamented dragonfly (Pachydiplax longipennis). Higher larval body condition indeed enhanced the initial development of its intrasexually selected wing coloration, but was opposed by viability selection in the presence of large aeshnid predators. In contrast, viability selection did not oppose larval body condition in pools when aeshnids were absent, and was not affected when we manipulated cannibalism risk. Trade-offs between larval survival and ornament development, mediated through the conflicting effects of body condition, therefore occurred only under high predation risk. We additionally characterized how body condition influences several traits associated with predator avoidance. Although body condition did not affect burst distance, it did increase larval abdomen size, potentially making larvae easier targets for aeshnid predators. As high body condition similarly increases vulnerability to predators in many other animals, predator-mediated costs of juvenile resource accumulation could be a common, environment-specific limitation on the elaboration of sexually selected traits.

Phenotypic plasticity and remodeling in the stress-induced Caenorhabditis elegans dauer.

PubMed

Androwski, Rebecca J; Flatt, Kristen M; Schroeder, Nathan E

2017-09-01

Organisms are often capable of modifying their development to better suit their environment. Under adverse conditions, the nematode Caenorhabditis elegans develops into a stress-resistant alternative larval stage called dauer. The dauer stage is the primary survival stage for C. elegans in nature. Large-scale tissue remodeling during dauer conveys resistance to harsh environments. The environmental and genetic regulation of the decision to enter dauer has been extensively studied. However, less is known about the mechanisms regulating tissue remodeling. Changes to the cuticle and suppression of feeding in dauers lead to an increased resistance to external stressors. Meanwhile reproductive development arrests during dauer while preserving the ability to reproduce once favorable environmental conditions return. Dramatic remodeling of neurons, glia, and muscles during dauer likely facilitate dauer-specific behaviors. Dauer-specific pulsation of the excretory duct likely mediates a response to osmotic stress. The power of C. elegans genetics has uncovered some of the molecular pathways regulating dauer tissue remodeling. In addition to genes that regulate single remodeling events, several mutants result in pleiotropic defects in dauer remodeling. This review details the individual aspects of morphological changes that occur during dauer formation and discusses molecular mechanisms regulating these processes. The dauer stage provides us with an excellent model for understanding phenotypic plasticity and remodeling from the individual cell to an entire animal. WIREs Dev Biol 2017, 6:e278. doi: 10.1002/wdev.278 For further resources related to this article, please visit the WIREs website. © 2017 Wiley Periodicals, Inc.

The distribution of Paenibacillus larvae spores in adult bees and honey and larval mortality, following the addition of American foulbrood diseased brood or spore-contaminated honey in honey bee (Apis mellifera) colonies.

PubMed

Lindström, Anders; Korpela, Seppo; Fries, Ingemar

2008-09-01

Within colony transmission of Paenibacillus larvae spores was studied by giving spore-contaminated honey comb or comb containing 100 larvae killed by American foulbrood to five experimental colonies respectively. We registered the impact of the two treatments on P. larvae spore loads in adult bees and honey and on larval mortality by culturing for spores in samples of adult bees and honey, respectively, and by measuring larval survival. The results demonstrate a direct effect of treatment on spore levels in adult bees and honey as well as on larval mortality. Colonies treated with dead larvae showed immediate high spore levels in adult bee samples, while the colonies treated with contaminated honey showed a comparable spore load but the effect was delayed until the bees started to utilize the honey at the end of the flight season. During the winter there was a build up of spores in the adult bees, which may increase the risk for infection in spring. The results confirm that contaminated honey can act as an environmental reservoir of P. larvae spores and suggest that less spores may be needed in honey, compared to in diseased brood, to produce clinically diseased colonies. The spore load in adult bee samples was significantly related to larval mortality but the spore load of honey samples was not.

Botanical compound p-anisaldehyde repels larval lone star tick, Amblyomma americanum (L.) (Acari: Ixodidae), and halts reproduction by gravid adults

USDA-ARS?s Scientific Manuscript database

The lone star tick, Amblyomma americanum (L.), widely distributed across eastern, southeastern, and midwestern regions of the United States and south into Mexico, is an obligate blood feeder that attaches to three hosts during the larval, nymphal, and adult stages. White-tailed deer and wild turkey ...

Analysis of gene expression in the midgut of Bombyx mori during the larval molting stage.

PubMed

Yang, Bing; Huang, Wuren; Zhang, Jie; Xu, Qiuyun; Zhu, Shoulin; Zhang, Qiaoli; Beerntsen, Brenda T; Song, Hongsheng; Ling, Erjun

2016-11-03

Insects can be models for understanding human intestinal infection and pathology. Molting, a special period during which the old insect cuticle is shed and a new one is produced, is crucial for insect development. Holometabolous insects may experience several larva-to-larva moltings to become larger, a pupal molt and adult eclosion to become adults. During the larval molts, they stop feeding and become quiescent. Although the molting larvae become quiescent, it is not known if changes in microbiome, physiology, development and immunity of midguts occur. Transcriptome analysis indicated that functions such as metabolism, digestion, and transport may become reduced due to the downregulated expression of many associated genes. During the molting stage, midguts harbor less microflora and DNA synthesis decreases. Both ecdysone and juvenile hormone in the larval midgut likely degrade after entering the larva-to-larva molting stage. However, at 12 h after ecdysis, the feeding larvae of 5th instars that were injected with 20-hydroxyecdysone entered a molting-like stage, during which changes in midgut morphology, DNA synthesis, gene expression, and microflora exhibited the same patterns as observed in the actual molting state. This study is important for understanding insect midgut physiology, development and immunity during a special development stage when no food is ingested. Although the molting larva becomes immobile and quiescent, we demonstrate that numerous changes occur in midgut morphology, physiology, metabolism and microbiome during this period.

The effect of larval and early adult experience on behavioural plasticity of the aphid parasitoid Aphidius ervi (Hymenoptera, Braconidae, Aphidiinae)

NASA Astrophysics Data System (ADS)

Villagra, Cristian A.; Pennacchio, Francesco; Niemeyer, Hermann M.

2007-11-01

The relevance of the integration of preimaginal and eclosion experiences on the subsequent habitat preferences and mate finding by the adult has been rarely tested in holometabolous insects. In this work, the effect of larval and early adult experiences on the behavioural responses of adult males of the aphid parasitoid, Aphidius ervi, towards volatiles from the host-plant complex (HPC) and from conspecific females were evaluated. Two experience factors were considered: host diet (normal diet=ND; artificial diet=AD), and eclosion, i.e. extraction or non-extraction of the parasitoid larva from the parasitised aphid (extracted=EX; non-extracted=NE). Thus, four treatments were set up: ND/NE, ND/EX, AD/NE and AD/EX. Glass Y-tube olfactometers were used to investigate the responses of adult A. ervi males to the odour sources used. Males from the ND/NE treatment showed a shorter latency to the first choice of olfactometer arms, displayed a marked preference towards the HPC olfactometer arm, and spent more time in the HPC arm than males from the other treatments. Only the interaction of host diet and eclosion experiences proved to be relevant in explaining the differences in latency to first choice, time spent in olfactometers arms, and behaviours displayed in the olfactometer arms. These results show the importance of the integration of larval and eclosion experiences in the development of stereotyped responses of the adults. This process may involve memory retention from the preimaginal and emergence period, but further research is needed to disentangle the contribution of each stage. The response to conspecific females was much less affected by the treatments in relation to first arm choice and times in olfactometer arms, suggesting a pheromone-mediated behaviour, even though a prompter and more intense wing fanning courtship behaviour was registered in the ND/NE males compared to males from the AD/NE treatment. These results show that sexual behaviours are less

The skin is an important bulwark of acquired immunity against intestinal helminths

PubMed Central

Obata-Ninomiya, Kazushige; Ishiwata, Kenji; Tsutsui, Hidemitsu; Nei, Yuichiro; Yoshikawa, Soichiro; Kawano, Yohei; Minegishi, Yoshiyuki; Ohta, Nobuo; Watanabe, Naohiro; Kanuka, Hirotaka

2013-01-01

Once animals have experienced a helminthic infection, they often show stronger protective immunity against subsequent infections. Although helminthic infections are well known to elicit Th2-type immune responses, it remains ill-defined where and how acquired protection is executed. Here we show that skin-invading larvae of the intestinal helminth Nippostrongylus brasiliensis are surrounded by skin-infiltrating cells and are prevented from migrating out of infected skin during the second but not the first infection. B cell– or IgE receptor FcεRI–deficient mice showed impaired larval trapping in the skin. Selective ablation of basophils, but not mast cells, abolished the larval trapping, leading to increased worm burden in the lung and hence severe lung injury. Skin-infiltrating basophils produced IL-4 that in turn promoted the generation of M2-type macrophages, leading to the larval trapping in the skin through arginase-1 production. Basophils had no apparent contribution to worm expulsion from the intestine. This study thus reveals a novel mode of acquired antihelminth immunity, in which IgE-armed basophils mediate skin trapping of larvae, thereby limiting lung injury caused by larval migration. PMID:24166714

Spatial pattern analysis of nuclear migration in remodelled muscles during Drosophila metamorphosis.

PubMed

Kuleesha; Feng, Lin; Wasser, Martin

2017-07-10

Many human muscle wasting diseases are associated with abnormal nuclear localization. During metamorphosis in Drosophila melanogaster, multi-nucleated larval dorsal abdominal muscles either undergo cell death or are remodeled to temporary adult muscles. Muscle remodeling is associated with anti-polar nuclear migration and atrophy during early pupation followed by polar migration and muscle growth during late pupation. Muscle remodeling is a useful model to study genes involved in myonuclear migration. Previously, we showed that loss of Cathepsin-L inhibited anti-polar movements, while knockdown of autophagy-related genes affected nuclear positioning along the medial axis in late metamorphosis. To compare the phenotypic effects of gene perturbations on nuclear migration more objectively, we developed new descriptors of myonuclear distribution. To obtain nuclear pattern features, we designed an algorithm to detect and track nuclear regions inside live muscles. Nuclear tracks were used to distinguish between fast moving nuclei associated with fragments of dead muscles (sarcolytes) and slow-moving nuclei inside remodelled muscles. Nuclear spatial pattern features, such as longitudinal (lonNS) and lateral nuclear spread (latNS), allowed us to compare nuclear migration during muscle remodelling in different genetic backgrounds. Anti-polar migration leads to a lonNS decrease. As expected, lack of myonuclear migration caused by the loss of Cp1 was correlated with a significantly lower lonNS decrease. Unexpectedly, the decrease in lonNS was significantly enhanced by Atg9, Atg5 and Atg18 silencing, indicating that the loss of autophagy promotes the migration and clustering of nuclei. Loss of autophagy also caused a scattering of nuclei along the lateral axis, leading to a two-row as opposed to single row distribution in control muscles. Increased latNS resulting from knockdown of Atg9 and Atg18 was correlated with increased muscle diameter, suggesting that the wider muscle

Insect acetyl-CoA carboxylase: activity during the larval, pupal and adult stages of insect development.

PubMed

Goldring, J P; Read, J S

1993-12-01

1. The activity of the lipogenic enzyme, acetyl-CoA carboxylase, was investigated in four insect species; Bombyx mori (Lepidoptera), Tenebrio molitor (Coleoptera), Glossina morsitans and Sarcophaga nodosa (Diptera). 2. Acetyl-CoA carboxylase activity in larval, pupal and adult forms was compared with the saponifiable lipid mass at each stage of the life-cycle, and found to follow similar patterns except for Tenebrio molitor. 3. The results are examined in relation to known metabolic requirements for each insect.

Determination of the efficiency of diets for larval development in mass rearing Aedes aegypti (Diptera: Culicidae).

PubMed

Gunathilaka, P A D H N; Uduwawala, U M H U; Udayanga, N W B A L; Ranathunge, R M T B; Amarasinghe, L D; Abeyewickreme, W

2017-11-23

Larval diet quality and rearing conditions have a direct and irreversible effect on adult traits. Therefore, the current study was carried out to optimize the larval diet for mass rearing of Aedes aegypti, for Sterile Insect Technique (SIT)-based applications in Sri Lanka. Five batches of 750 first instar larvae (L 1) of Ae. aegypti were exposed to five different concentrations (2-10%) of International Atomic Energy Agency (IAEA) recommended the larval diet. Morphological development parameters of larva, pupa, and adult were detected at 24 h intervals along with selected growth parameters. Each experiment was replicated five times. General Linear Modeling along with Pearson's correlation analysis were used for statistical treatments. Significant differences (P < 0.05) among the larvae treated with different concentrations were found using General Linear Modeling in all the stages namely: total body length and the thoracic length of larvae; cephalothoracic length and width of pupae; thoracic length, thoracic width, abdominal length and the wing length of adults; along with pupation rate and success, sex ratio, adult success, fecundity and hatching rate of Ae. aegypti. The best quality adults can be produced at larval diet concentration of 10%. However, the 8% larval diet concentration was most suitable for adult male survival.

Effect of Larval Competition on Extrinsic Incubation Period and Vectorial Capacity of Aedes albopictus for Dengue Virus.

PubMed

Bara, Jeffrey; Rapti, Zoi; Cáceres, Carla E; Muturi, Ephantus J

2015-01-01

Despite the growing awareness that larval competition can influence adult mosquito life history traits including susceptibility to pathogens, the net effect of larval competition on human risk of exposure to mosquito-borne pathogens remains poorly understood. We examined how intraspecific larval competition affects dengue-2 virus (DENV-2) extrinsic incubation period and vectorial capacity of its natural vector Aedes albopictus. Adult Ae. albopictus from low and high-larval density conditions were orally challenged with DENV-2 and then assayed for virus infection and dissemination rates following a 6, 9, or 12-day incubation period using real-time quantitative reverse transcription PCR. We then modeled the effect of larval competition on vectorial capacity using parameter estimates obtained from peer-reviewed field and laboratory studies. Larval competition resulted in significantly longer development times, lower emergence rates, and smaller adults, but did not significantly affect the extrinsic incubation period of DENV-2 in Ae. albopictus. Our vectorial capacity models suggest that the effect of larval competition on adult mosquito longevity likely has a greater influence on vectorial capacity relative to any competition-induced changes in vector competence. Furthermore, we found that large increases in the viral dissemination rate may be necessary to compensate for small competition-induced reductions in daily survivorship. Our results indicate that mosquito populations that experience stress from larval competition are likely to have a reduced vectorial capacity, even when susceptibility to pathogens is enhanced.

Effect of Larval Competition on Extrinsic Incubation Period and Vectorial Capacity of Aedes albopictus for Dengue Virus

PubMed Central

Bara, Jeffrey; Rapti, Zoi; Cáceres, Carla E.; Muturi, Ephantus J.

2015-01-01

Despite the growing awareness that larval competition can influence adult mosquito life history traits including susceptibility to pathogens, the net effect of larval competition on human risk of exposure to mosquito-borne pathogens remains poorly understood. We examined how intraspecific larval competition affects dengue-2 virus (DENV-2) extrinsic incubation period and vectorial capacity of its natural vector Aedes albopictus. Adult Ae. albopictus from low and high-larval density conditions were orally challenged with DENV-2 and then assayed for virus infection and dissemination rates following a 6, 9, or 12-day incubation period using real-time quantitative reverse transcription PCR. We then modeled the effect of larval competition on vectorial capacity using parameter estimates obtained from peer-reviewed field and laboratory studies. Larval competition resulted in significantly longer development times, lower emergence rates, and smaller adults, but did not significantly affect the extrinsic incubation period of DENV-2 in Ae. albopictus. Our vectorial capacity models suggest that the effect of larval competition on adult mosquito longevity likely has a greater influence on vectorial capacity relative to any competition-induced changes in vector competence. Furthermore, we found that large increases in the viral dissemination rate may be necessary to compensate for small competition-induced reductions in daily survivorship. Our results indicate that mosquito populations that experience stress from larval competition are likely to have a reduced vectorial capacity, even when susceptibility to pathogens is enhanced. PMID:25951173

Condition of larval red snapper (Lutjanus campechanus) relative to environmental variability and the Deepwater Horizon oil spill

NASA Astrophysics Data System (ADS)

Hernandez, F. J., Jr.; Filbrun, J. E.; Fang, J.; Ransom, J. T.

2016-09-01

The Deepwater Horizon oil spill (DWHOS) spatially and temporally overlapped with the spawning of many fish species, including Red Snapper, one of the most economically important reef fish in the Gulf of Mexico. To investigate potential impacts of the DWHOS on larval Red Snapper, data from a long-term ichthyoplankton survey off the coast of Alabama were used to examine: (1) larval abundances among pre-impact (2007-2009), impact (2010), and post-impact (2011, 2013) periods; (2) proxies for larval condition (size-adjusted morphometric relationships and dry weight) among the same periods; and (3) the effects of background environmental variation on larval condition. We found that larval Red Snapper were in poorer body condition during 2010, 2011, and 2013 as compared to the 2007-2009 period, a trend that was strongly (and negatively) related to variation in Mobile Bay freshwater discharge. However, larvae collected during and after 2010 were in relatively poor condition even after accounting for variation in freshwater discharge and other environmental variables. By contrast, no differences in larval abundance were detected during these survey years. Taken together, larval supply did not change relative to the timing of the DWHOS, but larval condition was negatively impacted. Even small changes in condition can affect larval survival, so these trends may have consequences for recruitment of larvae to juvenile and adult life stages.

Acute and Chronic Effects of Dietary Lactose in Adult Rats Are not Explained by Residual Intestinal Lactase Activity

PubMed Central

van de Heijning, Bert J. M.; Kegler, Diane; Schipper, Lidewij; Voogd, Eline; Oosting, Annemarie; van der Beek, Eline M.

2015-01-01

Neonatal rats have a high intestinal lactase activity, which declines around weaning. Yet, the effects of lactose-containing products are often studied in adult animals. This report is on the residual, post-weaning lactase activity and on the short- and long-term effects of lactose exposure in adult rats. Acutely, the postprandial plasma response to increasing doses of lactose was studied, and chronically, the effects of a 30% lactose diet fed from postnatal (PN) Day 15 onwards were evaluated. Intestinal lactase activity, as assessed both in vivo and in vitro, was compared between both test methods and diet groups (lactose vs. control). A 50%–75% decreased digestive capability towards lactose was observed from weaning into adulthood. Instillation of lactose in adult rats showed disproportionally low increases in plasma glucose levels and did not elicit an insulin response. However, gavages comprising maltodextrin gave rise to significant plasma glucose and insulin responses, indicative of a bias of the adult GI tract to digest glucose polymers. Despite the residual intestinal lactase activity shown, a 30% lactose diet was poorly digested by adult rats: the lactose diet rendered the animals less heavy and virtually devoid of body fat, whereas their cecum tripled in size, suggesting an increased bacterial fermentation. The observed acute and chronic effects of lactose exposure in adult rats cannot be explained by the residual intestinal lactase activity assessed. PMID:26184291

Similar Responses of Intestinal T Cells From Untreated Children and Adults With Celiac Disease to Deamidated Gluten Epitopes.

PubMed

Ráki, Melinda; Dahal-Koirala, Shiva; Yu, Hao; Korponay-Szabó, Ilma R; Gyimesi, Judit; Castillejo, Gemma; Jahnsen, Jørgen; Qiao, Shuo-Wang; Sollid, Ludvig M

2017-09-01

Celiac disease is a chronic small intestinal inflammatory disorder mediated by an immune response to gluten peptides in genetically susceptible individuals. Celiac disease is often diagnosed in early childhood, but some patients receive a diagnosis late in life. It is uncertain whether pediatric celiac disease is distinct from adult celiac disease. It has been proposed that gluten-reactive T cells in children recognize deamidated and native gluten epitopes, whereas T cells from adults only recognize deamidated gluten peptides. We studied the repertoire of gluten epitopes recognized by T cells from children and adults. We examined T-cell responses against gluten by generating T-cell lines and T-cell clones from intestinal biopsies of adults and children and tested proliferative response to various gluten peptides. We analyzed T cells from 14 children (2-5 years old) at high risk for celiac disease who were followed for celiac disease development. We also analyzed T cells from 6 adults (26-55 years old) with untreated celiac disease. All children and adults were positive for HLA-DQ2.5. Biopsies were incubated with gluten digested with chymotrypsin (modified or unmodified by the enzyme transglutaminase 2) or the peptic-tryptic digest of gliadin (in native and deamidated forms) before T-cell collection. Levels of T-cell responses were higher to deamidated gluten than to native gluten in children and adults. T cells from children and adults each reacted to multiple gluten epitopes. Several T-cell clones were cross-reactive, especially clones that recognized epitopes from γ-and ω-gliadin. About half of the generated T-cell clones from children and adults reacted to unknown epitopes. T-cell responses to different gluten peptides appear to be similar between adults and children at the time of diagnosis of celiac disease. Copyright © 2017 AGA Institute. Published by Elsevier Inc. All rights reserved.

Wandering spleen with gastric volvulus and intestinal non-rotation in an adult male patient

PubMed Central

Kohda, Eiichi; Iizuka, Yuo; Nagamoto, Masashi; Ishii, Tomotaka; Saida, Yoshihisa; Shimizu, Norikazu; Gomi, Tatsuya

2013-01-01

We report an extremely rare case of wandering spleen (WS) complicated with gastric volvulus and intestinal non-rotation in a male adult. A 22-year-old man who had been previously treated for Wilson disease was admitted with severe abdominal pain. Radiological findings showed WS in the midline of the pelvic area. The stomach was mesenteroaxially twisted and intestinal non-rotation was observed. Radiology results did not show any evidence of splenic or gastrointestinal (GI) infarction. Elective emergency laparoscopy confirmed WS and intestinal non-rotation; however, gastric volvulus was not observed. It was suspected that the stomach had untwisted when gastric and laparoscopic tubes were inserted. Surgery is strongly recommended for WS because of the high risk of serious complications; however, some asymptomatic adult patients are still treated conservatively, such as the patient in this study. The present case is reported with reference to the literature. PMID:24349711

Wandering spleen with gastric volvulus and intestinal non-rotation in an adult male patient.

PubMed

Ooka, Minako; Kohda, Eiichi; Iizuka, Yuo; Nagamoto, Masashi; Ishii, Tomotaka; Saida, Yoshihisa; Shimizu, Norikazu; Gomi, Tatsuya

2013-01-01

We report an extremely rare case of wandering spleen (WS) complicated with gastric volvulus and intestinal non-rotation in a male adult. A 22-year-old man who had been previously treated for Wilson disease was admitted with severe abdominal pain. Radiological findings showed WS in the midline of the pelvic area. The stomach was mesenteroaxially twisted and intestinal non-rotation was observed. Radiology results did not show any evidence of splenic or gastrointestinal (GI) infarction. Elective emergency laparoscopy confirmed WS and intestinal non-rotation; however, gastric volvulus was not observed. It was suspected that the stomach had untwisted when gastric and laparoscopic tubes were inserted. Surgery is strongly recommended for WS because of the high risk of serious complications; however, some asymptomatic adult patients are still treated conservatively, such as the patient in this study. The present case is reported with reference to the literature.

Body composition, adipokines, bone mineral density and bone remodeling markers in relation to IGF-1 levels in adults with Prader-Willi syndrome.

PubMed

van Nieuwpoort, I Caroline; Twisk, Jos W R; Curfs, Leopold M G; Lips, Paul; Drent, Madeleine L

2018-01-01

In patients with Prader-Willi syndrome (PWS) body composition is abnormal and alterations in appetite regulating factors, bone mineral density and insulin-like growth factor-1 (IGF-1) levels have been described. Studies in PWS adults are limited. In this study, we investigated body composition, appetite regulating peptides, bone mineral density and markers of bone remodeling in an adult PWS population. Furthermore, we investigated the association between these different parameters and IGF-1 levels because of the described similarities with growth hormone deficient patients. In this cross-sectional observational cohort study in a university hospital setting we studied fifteen adult PWS patients. Anthropometric and metabolic parameters, IGF-1 levels, bone mineral density and bone metabolism were evaluated. The homeostasis model assessment of insulin resistance (HOMA2-IR) was calculated. Fourteen healthy siblings served as a control group for part of the measurements. In the adult PWS patients, height, fat free mass, IGF-1 and bone mineral content were significantly lower when compared to controls; body mass index (BMI), waist, waist-to-hip ratio and fat mass were higher. There was a high prevalence of osteopenia and osteoporosis in the PWS patients. Also, appetite regulating peptides and bone remodelling markers were aberrant when compared to reference values. Measurements of body composition were significantly correlated to appetite regulating peptides and high-sensitive C-reactive protein (hs-CRP), furthermore HOMA was correlated to BMI and adipokines. In adults with Prader-Willi syndrome alterations in body composition, adipokines, hs-CRP and bone mineral density were demonstrated but these were not associated with IGF-1 levels. Further investigations are warranted to gain more insight into the exact pathophysiology and the role of these alterations in the metabolic and cardiovascular complications seen in PWS, so these complications can be prevented or treated as

Role of specific activators of intestinal amino acid transport in Bombyx mori larval growth and nutrition.

PubMed

Leonardi, M G; Casartelli, M; Fiandra, L; Parenti, P; Giordana, B

2001-12-01

Nutrient absorption and its modulation are critical for animal growth. In this paper, we demonstrate that leucine methyl ester (Leu-OMe) can greatly increase the activity of the transport system responsible for the absorption of most essential amino acids in the larval midgut of the silkworm Bombyx mori. We investigated leucine uptake activation by Leu-OMe in brush border membrane vesicles and in the apical membrane of epithelial cells in the midgut incubated in vitro. Moreover, the addition of this strong activator of amino acid absorption to diet significantly affected larval growth. Silkworms fed on artificial diet supplemented with Leu-OMe reached maximum body weight 12-18 h before control larvae, and produced cocoon shells up to 20% heavier than those of controls. The activation of amino acid absorption plays an essential role in larval development so that larval growth and cocoon production similar to controls reared on an artificial diet with 25% of dry mulberry leaf powder were observed in silkworms fed on an artificial diet with only 5% of mulberry powder. Arch. Copyright 2001 Wiley-Liss, Inc.

Effect of endurance exercise training on left ventricular size and remodeling in older adults with hypertension.

PubMed

Turner, M J; Spina, R J; Kohrt, W M; Ehsani, A A

2000-04-01

It is not known whether exercise training can induce a reduction of blood pressure (BP) and a regression of left ventricular hypertrophy (LVH) in older hypertensive subjects. This study was designed to determine whether endurance exercise training, by lowering BP, can induce regression of LVH and left ventricular (LV) concentric remodeling in older hypertensive adults. We studied 11 older adults with mild to moderate hypertension (BP 152.0 +/- 2.5/91.3 +/- 1.5 mm Hg, mean +/- SE), 65.5 +/- 1.2 years old, who exercised for 6.8 +/- 3.8 months. Seven sedentary hypertensive (BP 153 +/- 3/89 +/- 2 mm Hg) subjects, 68.5 +/- 1 years old, served as controls. LV size and geometry and function were assessed with the use of two-dimensional echocardiography. Exercise training increased aerobic power by 16% (p < .001), and it decreased systolic (p < .05) and diastolic (p < .05) BP, LV wall thickness (from 12.8 +/- 0.4 mm to 11.3 +/- 0.3 mm; p < .05), and the wall thickness-to-radius (h/r) ratio (from 0.48 +/- 0.02 to 0.41 +/- 0.01; p < .05). There were no significant changes in the controls. The changes in LV mass index (deltaLVMI) were different between the two groups. LV mass index decreased in the exercise group (deltaLVMI - 14.3 +/- 3.3 g) but not in the controls (deltaLVMI 1.4 +/- 4.1 g; p = .009). A multiple stepwise regression analysis showed that among clinical and physiological variables including changes in resting systolic BP, aerobic power, body mass index, and systolic BP during submaximal and maximal exercise, only the reduction in resting systolic BP correlated significantly with a regression of concentric remodeling (delta h/r ratio r = .80; p = .003). The other variables did not add to the ability of the model to predict changes in the h/r ratio. The data suggest that exercise training can reduce BP and induce partial regression of LVH and LV concentric remodeling in older adults with mild or moderate hypertension.

Trait-based Modeling of Larval Dispersal in the Gulf of Maine

NASA Astrophysics Data System (ADS)

Jones, B.; Richardson, D.; Follows, M. J.; Hill, C. N.; Solow, A.; Ji, R.

2016-02-01

Population connectivity of marine species is the inter-generational movement of individuals among geographically separated subpopulations and is a crucial determinant of population dynamics, community structure, and optimal management strategies. For many marine species, population connectivity is largely determined by the dispersal patterns that emerge from a pelagic larval phase. These dispersal patterns are a result of interactions between the physical environment, adult spawning strategy, and larval ecology. Using a generalized trait-based model that represents the adult spawning strategy as a distribution of larval releases in time and space and the larval trait space with the pelagic larval duration, vertical swimming behavior, and settlement habitat preferences, we simulate dispersal patterns in the Gulf of Maine and surrounding regions. We implement this model as an individual-based simulation that tracks Lagrangian particles on a graphics processing unit as they move through hourly archived output from the Finite-Volume Community Ocean Model. The particles are released between the Hudson Canyon and Nova Scotia and the release distributions are determined using a novel method that minimizes the number of simulations required to achieve a predetermined level of precision for the connectivity matrices. The simulated larvae have a variable pelagic larval duration and exhibit multiple forms of dynamic depth-keeping behavior. We describe how these traits influence the dispersal trajectories and connectivity patterns among regions in the northwest Atlantic. Our description includes the probability of successful recruitment, patchiness of larval distributions, and the variability of these properties in time and space under a variety of larval dispersal strategies.

Hormonal activation of let-7-C microRNAs via EcR is required for adult Drosophila melanogaster morphology and function

PubMed Central

Chawla, Geetanjali; Sokol, Nicholas S.

2012-01-01

Steroid hormones and their nuclear receptors drive developmental transitions in diverse organisms, including mammals. In this study, we show that the Drosophila steroid hormone 20-hydroxyecdysone (20E) and its nuclear receptor directly activate transcription of the evolutionarily conserved let-7-complex (let-7-C) locus, which encodes the co-transcribed microRNAs miR-100, let-7 and miR-125. These small RNAs post-transcriptionally regulate the expression of target genes, and are required for the remodeling of the Drosophila neuromusculature during the larval-to-adult transition. Deletion of three 20E responsive elements located in the let-7-C locus results in reduced levels of let-7-C microRNAs, leading to neuromuscular and behavioral defects in adults. Given the evolutionary conservation of let-7-C microRNA sequences and temporal expression profiles, these findings indicate that steroid hormone-coupled control of let-7-C microRNAs is part of an ancestral pathway controlling the transition from larval-to-reproductive animal forms. PMID:22510985

Correlated evolution between mode of larval development and habitat in muricid gastropods.

PubMed

Pappalardo, Paula; Rodríguez-Serrano, Enrique; Fernández, Miriam

2014-01-01

Larval modes of development affect evolutionary processes and influence the distribution of marine invertebrates in the ocean. The decrease in pelagic development toward higher latitudes is one of the patterns of distribution most frequently discussed in marine organisms (Thorson's rule), which has been related to increased larval mortality associated with long pelagic durations in colder waters. However, the type of substrate occupied by adults has been suggested to influence the generality of the latitudinal patterns in larval development. To help understand how the environment affects the evolution of larval types we evaluated the association between larval development and habitat using gastropods of the Muricidae family as a model group. To achieve this goal, we collected information on latitudinal distribution, sea water temperature, larval development and type of substrate occupied by adults. We constructed a molecular phylogeny for 45 species of muricids to estimate the ancestral character states and to assess the relationship between traits using comparative methods in a Bayesian framework. Our results showed high probability for a common ancestor of the muricids with nonpelagic (and nonfeeding) development, that lived in hard bottoms and cold temperatures. From this ancestor, a pelagic feeding larva evolved three times, and some species shifted to warmer temperatures or sand bottoms. The evolution of larval development was not independent of habitat; the most probable evolutionary route reconstructed in the analysis of correlated evolution showed that type of larval development may change in soft bottoms but in hard bottoms this change is highly unlikely. Lower sea water temperatures were associated with nonpelagic modes of development, supporting Thorson's rule. We show how environmental pressures can favor a particular mode of larval development or transitions between larval modes and discuss the reacquisition of feeding larva in muricids gastropods.

Total midgut volvulus in adults with intestinal malrotation. Report of eleven patients.

PubMed

Kotobi, H; Tan, V; Lefèvre, J; Duramé, F; Audry, G; Parc, Y

2017-06-01

Total small-intestinal volvulus with malrotation (TSIVM) classically presents in the neonatal period; it occurs much less frequently in the adult and is often misdiagnosed. Prognosis is directly related to the degree and duration of intestinal ischemia. Our goal is to describe our experience with TSIVM in the adult, to identify any specific findings and to discuss its management. Eleven patients who had undergone surgery for TSIVM at three centers between 1992 and 2012 were included. Surgery was performed as an emergency for five patients and surgery was elective for six. Mean follow-up was 63 months (range: 12-270). Six patients had had previous abdominal surgery. In nine cases, the diagnosis of TSIVM was made preoperatively, mainly by CT scan in eight cases. Seven patients had associated congenital failure of retroperitoneal fixation of the right colon and all of these underwent a Ladd procedure. The mortality rate was zero. Of the five patients who underwent emergency surgery, three required intestinal resections, one of whom developed a short bowel syndrome. The six patients who underwent surgery electively had no surgical complications. TSIVM is a very unusual finding in adult patients. The diagnosis can be made by CT scan with IV and oral contrast, but it often comes to light only at the time of surgery, even though the patients have often had recurrent episodes of abdominal symptomatology that dated back to childhood. The Ladd procedure, consisting of division of Ladd's bands, widening of the mesentery, and incidental appendectomy, remains the standard surgical repair. Digestive surgeons who care for adults should be familiar with this procedure, and it should be performed, as often as possible, with the assistance of a pediatric surgeon. Copyright © 2016. Published by Elsevier Masson SAS.

To Remodel or To Build?

ERIC Educational Resources Information Center

Rosenblum, Todd

2009-01-01

The question of remodeling an existing house to make it wheelchair accessible or building a new barrier-free house is a difficult decision. This article presents some initial questions and considerations followed by a list of pros and cons for remodeling an existing house vs. building a new house.

Rapid evolution of larval life history, adult immune function and flight muscles in a poleward-moving damselfly.

PubMed

Therry, L; Nilsson-Örtman, V; Bonte, D; Stoks, R

2014-01-01

Although a growing number of studies have documented the evolution of adult dispersal-related traits at the range edge of poleward-expanding species, we know little about evolutionary changes in immune function or traits expressed by nondispersing larvae. We investigated differentiation in larval (growth and development) and adult traits (immune function and flight-related traits) between replicated core and edge populations of the poleward-moving damselfly Coenagrion scitulum. These traits were measured on individuals reared in a common garden experiment at two different food levels, as allocation trade-offs may be easier to detect under energy shortage. Edge individuals had a faster larval life history (growth and development rates), a higher adult immune function and a nearly significant higher relative flight muscle mass. Most of the differentiation between core and edge populations remained and edge populations had a higher relative flight muscle mass when corrected for latitude-specific thermal regimes, and hence could likely be attributed to the range expansion process per se. We here for the first time document a higher immune function in individuals at the expansion front of a poleward-expanding species and documented the rarely investigated evolution of faster life histories during range expansion. The rapid multivariate evolution in these ecological relevant traits between edge and core populations is expected to translate into changed ecological interactions and therefore has the potential to generate novel eco-evolutionary dynamics at the expansion front. © 2013 The Authors. Journal of Evolutionary Biology © 2013 European Society For Evolutionary Biology.

VEGF preconditioning leads to stem cell remodeling and attenuates age-related decay of adult hippocampal neurogenesis

PubMed Central

Licht, Tamar; Rothe, Gadiel; Kreisel, Tirzah; Wolf, Brachi; Benny, Ofra; Rooney, Alasdair G.; ffrench-Constant, Charles; Enikolopov, Grigori; Keshet, Eli

2016-01-01

Several factors are known to enhance adult hippocampal neurogenesis but a factor capable of inducing a long-lasting neurogenic enhancement that attenuates age-related neurogenic decay has not been described. Here, we studied hippocampal neurogenesis following conditional VEGF induction in the adult brain and showed that a short episode of VEGF exposure withdrawn shortly after the generation of durable new vessels (but not under conditions where newly made vessels failed to persist) is sufficient for neurogenesis to proceed at a markedly elevated level for many months later. Continual neurogenic increase over several months was not accompanied by accelerated exhaustion of the neuronal stem cell (NSC) reserve, thereby allowing neurogenesis to proceed at a markedly elevated rate also in old mice. Neurogenic enhancement by VEGF preconditioning was, in part, attributed to rescue of age-related NSC quiescence. Remarkably, VEGF caused extensive NSC remodelling manifested in transition of the enigmatic NSC terminal arbor onto long cytoplasmic processes engaging with and spreading over even remote blood vessels, a configuration reminiscent of early postnatal “juvenile” NSCs. Together, these findings suggest that VEGF preconditioning might be harnessed for long-term neurogenic enhancement despite continued exposure to an “aged” systemic milieu. PMID:27849577

Biomechanical remodeling of obstructed guinea pig jejunum

PubMed Central

Zhao, Jingbo; Liao, Donghua; Yang, Jian; Gregersen, Hans

2010-01-01

Data on morphological and biomechanical remodeling are needed to understand the mechanisms behind intestinal obstruction. The effect of partial obstruction on mechanical properties with reference to the zero-stress state and on the histomorphological properties of the guinea pig small intestine was determined in this study. Partial obstruction and sham operation were surgically created in mid-jejunum of guinea pigs. The animals survived 2, 4, 7, and 14 days respectively. The age-matched guinea pigs that were not operated served as normal controls. The segment proximal to the obstruction site was used for histological analysis, no-load state and zero-stress state data, and distension test. The segment for distension was immersed in an organ bath and inflated to 10 cmH20. The outer diameter change during the inflation was monitored using a microscope with CCD camera. Circumferential stresses and strains were computed from the diameter, pressure and the zero-stress state data. The opening angle and absolute value of residual strain decreased (P<0.01 and P<0.001) whereas the wall thickness, wall cross-sectional area, and the wall stiffness increased after 7 days obstruction (P<0.05, P<0.01). Histologically, the muscle and submucosa layers, especially the circumferential muscle layer increased in thickness after obstruction. The opening angle and residual strain mainly depended on the thickness of the muscle layer whereas the wall stiffness mainly depended on the thickness of the submucosa layer. In conclusion, the histomorphological and biomechanical properties of small intestine (referenced for the first time to the zero-stress state) remodel proximal to the obstruction site in a time-dependent manner. PMID:20189575

Microbial composition affects the performance of an artificial Tephritid larval diet.

PubMed

Rempoulakis, P; Sela Saldinger, S; Nemny-Lavy, E; Pinto, R; Birke, A; Nestel, D

2017-09-20

The present study investigated the patterns of microorganisms in an artificial larval diet during Dacus ciliatus (Diptera; Tephritidae) larval development. Microbial population contents in the diet of total heterotrophic bacteria, yeast and molds, coliform and lactobacilli, and their dynamics during development, were monitored. Initially, the microbial composition in diet trays failing to produce viable pupae and in trays successfully producing pupae and adult flies was characterized. The failing diet trays contained large populations of lactobacilli that increased during larval development, and low populations of coliforms. In contrast, the successful diet showed an increasing population of coliforms and a low, or undetected, population of lactobacilli. To study the hypothesis that lactobacilli affect D. ciliatus larval development, we conducted controlled inoculation experiments in which Lactobacillus plantarum was added into fresh diet at the time of egg seeding. L. plantarum inoculated trays showed no production of D. ciliatus. Control trays without lactobacilli inoculation showed variable results. One tray successfully produced viable pupae and adults, and showed a slight and slow increase in the indigenous populations of lactobacilli. The second tray, however, failed to produce pupae and showed a fast increase of the indigenous lactobacilli to very high levels. Monitored pH trends in L. plantarum-inoculated diet showed a sharp pH decrease during the first 4 days of larval development from 5 to less than 4 units, while successful diet, producing viable D. ciliatus pupae and adults, showed a moderate pH drop during most of the larval development period. The paper discusses the possible ecological interactions between D. ciliatus larvae, the microbial content of the diet and the physical properties of the diet. The discussion also points out at the usefulness of this approach in understanding and managing mass production parameters of tephritid fruit flies

Lactobacillus paracasei subsp. paracasei LC01 positively modulates intestinal microflora in healthy young adults.

PubMed

Zhang, Hao; Sun, Jing; Liu, Xianting; Hong, Chuan; Zhu, Yuanbo; Liu, Aiping; Li, Siqi; Guo, Huiyuan; Ren, Fazheng

2013-12-01

Lactobacillus paracasei subsp. paracasei LC01 (LC01) can tolerate intestinal stresses and has antioxidant activity. To evaluate the effect of the bacterium on human intestinal microflora, a randomized, double-blind, placebo-controlled human trial was carried out. Fifty-two healthy adult volunteers were randomized equally to two groups. One group consumed 12% (wt/vol) skimmed milk supplemented with 10(10) CFU of LC01 each day for the 4-week treatment period, and then consumed placebo in the next treatment period, separated by a 2-week washout. The other group followed the reverse order. Group-specific real-time PCR and biochemical analyses was used to determine the intestinal bacterial composition of fecal samples collected at the end of every period, and the concentration of short-chain fatty acids and ammonia. A significant inhibition in fecal Escherichia coli and increase in Lactobacillus, Bifidobacterium, and Roseburia intestinalis were observed after consumption of LC01. Acetic acid and butyric acid were significantly higher in the probiotic stage and fecal ammonia was significantly lower. The results indicated a modulation effect of LC01 on the intestinal microflora of young adults, suggesting a beneficial effect on bowel health. LC01 may have potential value as a probiotic.

The Effect of Larval Diet on Adult Survival, Swarming Activity and Copulation Success in Male Aedes aegypti (Diptera: Culicidae)

PubMed Central

Lang, Bethan J; Idugboe, Stefano; McManus, Kirelle; Drury, Florence; Qureshi, Alima

2018-01-01

Abstract Control of Aedes aegypti (L.) (Diptera: Culicidae) populations is vital for reducing the transmission of several pervasive human diseases. The success of new vector control technologies will be influenced by the fitness of laboratory-reared transgenic males. However, there has been relatively little published data on how rearing practices influence male fitness in Aedes mosquitoes. In the laboratory, the effect of larval food availability on adult male fitness was tested, using a range of different fitness measures. Larval food availability was demonstrated to be positively correlated with adult body size. Larger males survived longer and exhibited greater swarming activity. As a consequence, larger males may have more mating opportunities in the wild. However, we also found that within a swarm larger males did not have an increased likelihood of copulating with a female. The outcome of the mating competition experiments depended on the methodology used to mark the males. These results show that fitness assessment can vary depending on the measure analyzed, and the methodology used to determine it. Continued investigation into these fitness measures and methodologies, and critically, their utility for predicting male performance in the field, will increase the efficiency of vector control programs. PMID:29029298

RNA-Seq Comparison of Larval and Adult Malpighian Tubules of the Yellow Fever Mosquito Aedes aegypti Reveals Life Stage-Specific Changes in Renal Function.

PubMed

Li, Yiyi; Piermarini, Peter M; Esquivel, Carlos J; Drumm, Hannah E; Schilkey, Faye D; Hansen, Immo A

2017-01-01

Introduction: The life history of Aedes aegypti presents diverse challenges to its diuretic system. During the larval and pupal life stages mosquitoes are aquatic. With the emergence of the adult they become terrestrial. This shifts the organism within minutes from an aquatic environment to a terrestrial environment where dehydration has to be avoided. In addition, female mosquitoes take large blood meals, which present an entirely new set of challenges to salt and water homeostasis. Methods: To determine differences in gene expression associated with these different life stages, we performed an RNA-seq analysis of the main diuretic tissue in A. aegypti , the Malpighian tubules. We compared transcript abundance in 4th instar larvae to that of adult females and analyzed the data with a focus on transcripts that encode proteins potentially involved in diuresis, like water and solute channels as well as ion transporters. We compared our results against the model of potassium- and sodium chloride excretion in the Malpighian tubules proposed by Hine et al. (2014), which involves at least eight ion transporters and a proton-pump. Results: We found 3,421 of a total number of 17,478 (19.6%) unique transcripts with a P < 0.05 and at least a 2.5 fold change in expression levels between the two groups. We identified two novel transporter genes that are highly expressed in the adult Malpighian tubules, which have not previously been part of the transport model in this species and may play important roles in diuresis. We also identified candidates for hypothesized sodium and chloride channels. Detoxification genes were generally higher expressed in larvae. Significance: This study represents the first comparison of Malpighian tubule transcriptomes between larval and adult A. aegypti mosquitoes, highlighting key differences in their renal systems that arise as they transform from an aquatic filter-feeding larval stage to a terrestrial, blood-feeding adult stage.

Isolation and characterization of the stage-specific cytochrome b small subunit (CybS) of Ascaris suum complex II from the aerobic respiratory chain of larval mitochondria.

PubMed

Amino, Hisako; Osanai, Arihiro; Miyadera, Hiroko; Shinjyo, Noriko; Tomitsuka, Eriko; Taka, Hikari; Mineki, Reiko; Murayama, Kimie; Takamiya, Shinzaburo; Aoki, Takashi; Miyoshi, Hideto; Sakamoto, Kimitoshi; Kojima, Somei; Kita, Kiyoshi

2003-05-01

We recently reported that Ascaris suum mitochondria express stage-specific isoforms of complex II: the flavoprotein subunit and the small subunit of cytochrome b (CybS) of the larval complex II differ from those of adult enzyme, while two complex IIs share a common iron-sulfur cluster subunit (Ip). In the present study, A. suum larval complex II was highly purified to characterize the larval cytochrome b subunits in more detail. Peptide mass fingerprinting and N-terminal amino acid sequencing showed that the larval and adult cytochrome b (CybL) proteins are identical. In contrast, cDNA sequences revealed that the small subunit of larval cytochrome b (CybS(L)) is distinct from the adult CybS (CybS(A)). Furthermore, Northern analysis and immunoblotting showed stage-specific expression of CybS(L) and CybS(A) in larval and adult mitochondria, respectively. Enzymatic assays revealed that the ratio of rhodoquinol-fumarate reductase (RQFR) to succinate-ubiquinone reductase (SQR) activities and the K(m) values for quinones are almost identical for the adult and larval complex IIs, but that the fumarate reductase (FRD) activity is higher for the adult form than for the larval form. These results indicate that the adult and larval A. suum complex IIs have different properties than the complex II of the mammalian host and that the larval complex II is able to function as a RQFR. Such RQFR activity of the larval complex II would be essential for rapid adaptation to the dramatic change of oxygen availability during infection of the host.

[Main regulatory element (MRE) of the Danio rerio α/β-globin gene domain exerts enhancer activity toward the promoters of the embryonic-larval and adult globin genes].

PubMed

Kovina, A P; Petrova, N V; Razin, S V; Yarovaia, O V

2016-01-01

In warm-blooded vertebrates, the α- and β-globin genes are organized in domains of different types and are regulated in different fashion. In cold-blooded vertebrates and, in particular, the tropical fish Danio rerio, the α- and β-globin genes form two gene clusters. A major D. rerio globin gene cluster is in chromosome 3 and includes the α- and β-globin genes of embryonic-larval and adult types. The region upstream of the cluster contains c16orf35, harbors the main regulatory element (MRE) of the α-globin gene domain in warm-blooded vertebrates. In this study, transient transfection of erythroid cells with genetic constructs containing a reporter gene under the control of potential regulatory elements of the domain was performed to characterize the promoters of the embryonic-larval and adult α- and β-globin genes of the major cluster. Also, in the 5th intron of c16orf35 in Danio reriowas detected a functional analog of the warm-blooded vertebrate MRE. This enhancer stimulated activity of the promoters of both adult and embryonic-larval α- and β-globin genes.

Expected effects of reducing Oestrus ovis L. mature larval weight on adult populations.

PubMed

Cepeda-Palacios, R; Frugère, S; Dorchies, P

2000-06-27

In order to estimate the effects of eventual reductions in larval weight (LW) of Oestrus ovis L. as a measure of control, the correlation between mature LW and adult fly length (AL) in laboratory specimens (n=150) was calculated. The regression equation AL=5.62+10.65LW (r(2)=0.76) was obtained. This equation was then applied to estimate the mature LW of wild larvipositing females (n=51) to predict the minimum mature LW at which fly viability would be compromised. The critical weight, 0.28 g (standard error limits 0. 235, 0.323), was obtained from a small fly measuring 8.6mm in length. Data from 383 mature third instars were used to estimate, by statistical analysis, the expected effects of decreasing the mature LW on subsequent fly population size. A considerable mean reduction (38%) in adult populations might be achieved by a 40% reduction of mature LW, but this eventual reduction may be temporary due to the high reproductive rate in this species. Sex differences in mature LW and fly size are also reported.

A model of muscle atrophy based on live microscopy of muscle remodelling in Drosophila metamorphosis.

PubMed

Kuleesha, Yadav; Puah, Wee Choo; Wasser, Martin

2016-02-01

Genes controlling muscle size and survival play important roles in muscle wasting diseases. In Drosophila melanogaster metamorphosis, larval abdominal muscles undergo two developmental fates. While a doomed population is eliminated by cell death, another persistent group is remodelled and survives into adulthood. To identify and characterize genes involved in the development of remodelled muscles, we devised a workflow consisting of in vivo imaging, targeted gene perturbation and quantitative image analysis. We show that inhibition of TOR signalling and activation of autophagy promote developmental muscle atrophy in early, while TOR and yorkie activation are required for muscle growth in late pupation. We discovered changes in the localization of myonuclei during remodelling that involve anti-polar migration leading to central clustering followed by polar migration resulting in localization along the midline. We demonstrate that the Cathepsin L orthologue Cp1 is required for myonuclear clustering in mid, while autophagy contributes to central positioning of nuclei in late metamorphosis. In conclusion, studying muscle remodelling in metamorphosis can provide new insights into the cell biology of muscle wasting.

A model of muscle atrophy based on live microscopy of muscle remodelling in Drosophila metamorphosis

PubMed Central

Kuleesha, Yadav; Puah, Wee Choo; Wasser, Martin

2016-01-01

Genes controlling muscle size and survival play important roles in muscle wasting diseases. In Drosophila melanogaster metamorphosis, larval abdominal muscles undergo two developmental fates. While a doomed population is eliminated by cell death, another persistent group is remodelled and survives into adulthood. To identify and characterize genes involved in the development of remodelled muscles, we devised a workflow consisting of in vivo imaging, targeted gene perturbation and quantitative image analysis. We show that inhibition of TOR signalling and activation of autophagy promote developmental muscle atrophy in early, while TOR and yorkie activation are required for muscle growth in late pupation. We discovered changes in the localization of myonuclei during remodelling that involve anti-polar migration leading to central clustering followed by polar migration resulting in localization along the midline. We demonstrate that the Cathepsin L orthologue Cp1 is required for myonuclear clustering in mid, while autophagy contributes to central positioning of nuclei in late metamorphosis. In conclusion, studying muscle remodelling in metamorphosis can provide new insights into the cell biology of muscle wasting. PMID:26998322

Efficiency of three diets for larval development in mass rearing Aedes albopictus (Diptera: Culicidae).

PubMed

Puggioli, Arianna; Balestrino, F; Damiens, D; Lees, R S; Soliban, S M; Madakacherry, O; Dindo, M L; Bellini, R; Gilles, J R L

2013-07-01

A fundamental step in establishing a mass production system is the development of a larval diet that promotes high adult performance at a reasonable cost. To identify a suitable larval diet for Aedes albopictus (Skuse), three diets were compared: a standard laboratory diet used at the Centro Agricoltura Ambiente, Italy (CAA) and two diets developed specifically for mosquito mass rearing at the FAO/IAEA Laboratory, Austria. The two IAEA diets, without affecting survival to the pupal stage, resulted in a shorter time to pupation and to emergence when compared with the CAA diet. At 24 h from pupation onset, 50 and 90% of the male pupae produced on the CAA and IAEA diets, respectively, had formed and could be collected. The diet received during the larval stage affected the longevity of adult males with access to water only, with best results observed when using the CAA larval diet. However, similar longevity among diet treatments was observed when males were supplied with sucrose solution. No differences were observed in the effects of larval diet on adult male size or female fecundity and fertility. Considering these results, along with the relative costs of the three diets, the IAEA 2 diet is found to be the preferred choice for mass rearing of Aedes albopictus, particularly if a sugar meal can be given to adult males before release, to ensure their teneral reserves are sufficient for survival, dispersal, and mating in the field.

The development of the tapeworm Diphyllobothrium latum (L. 1756) (Cestoda; Pseudophyllidea) in its definitive hosts, with special references to the growth patterns of D. dendriticum (Nitzsch, 1824) and D. ditremum (Creplin, 1827).

PubMed

Andersen, K

1978-08-01

When Diphyllobothrium latum develops from larva to adult in a definitive host, it first sheds the entire larval 'body' before growth of an adult strobila starts. This process of shedding off the entire larval abothrial extremity, piece by piece, takes about 48 h. By this time the larva has usually reached the anterior third of the small intestine of the host. D. dendriticum and D. ditremum develop quite differently, although exhibiting similar anterior migrations. In these two species the larvae develop directly into adults without the larval 'body' first being shed. The implications of the observed differences in growth pattern between these three species of Diphyllobothrium to the classification of diphyllobothriid cestodes is discussed briefly.

The Developmental Intestinal Regulator ELT-2 Controls p38-Dependent Immune Responses in Adult C. elegans

PubMed Central

Block, Dena H. S.; Twumasi-Boateng, Kwame; Kang, Hae Sung; Carlisle, Jolie A.; Hanganu, Alexandru; Lai, Ty Yu-Jen; Shapira, Michael

2015-01-01

GATA transcription factors play critical roles in cellular differentiation and development. However, their roles in mature tissues are less understood. In C. elegans larvae, the transcription factor ELT-2 regulates terminal differentiation of the intestine. It is also expressed in the adult intestine, where it was suggested to maintain intestinal structure and function, and where it was additionally shown to contribute to infection resistance. To study the function of elt-2 in adults we characterized elt-2-dependent gene expression following its knock-down specifically in adults. Microarray analysis identified two ELT-2-regulated gene subsets: one, enriched for hydrolytic enzymes, pointed at regulation of constitutive digestive functions as a dominant role of adult elt-2; the second was enriched for immune genes that are induced in response to Pseudomonas aeruginosa infection. Focusing on the latter, we used genetic analyses coupled to survival assays and quantitative RT-PCR to interrogate the mechanism(s) through which elt-2 contributes to immunity. We show that elt-2 controls p38-dependent gene induction, cooperating with two p38-activated transcription factors, ATF-7 and SKN-1. This demonstrates a mechanism through which the constitutively nuclear elt-2 can impact induced responses, and play a dominant role in C. elegans immunity. PMID:26016853

Contributions of Anopheles larval control to malaria suppression in tropical Africa: review of achievements and potential.

PubMed

Walker, K; Lynch, M

2007-03-01

Malaria vector control targeting the larval stages of mosquitoes was applied successfully against many species of Anopheles (Diptera: Culicidae) in malarious countries until the mid-20th Century. Since the introduction of DDT in the 1940s and the associated development of indoor residual spraying (IRS), which usually has a more powerful impact than larval control on vectorial capacity, the focus of malaria prevention programmes has shifted to the control of adult vectors. In the Afrotropical Region, where malaria is transmitted mainly by Anopheles funestus Giles and members of the Anopheles gambiae Giles complex, gaps in information on larval ecology and the ability of An. gambiae sensu lato to exploit a wide variety of larval habitats have discouraged efforts to develop and implement larval control strategies. Opportunities to complement adulticiding with other components of integrated vector management, along with concerns about insecticide resistance, environmental impacts, rising costs of IRS and logistical constraints, have stimulated renewed interest in larval control of malaria vectors. Techniques include environmental management, involving the temporary or permanent removal of anopheline larval habitats, as well as larviciding with chemical or biological agents. This present review covers large-scale trials of anopheline larval control methods, focusing on field studies in Africa conducted within the past 15 years. Although such studies are limited in number and scope, their results suggest that targeting larvae, particularly in human-made habitats, can significantly reduce malaria transmission in appropriate settings. These approaches are especially suitable for urban areas, where larval habitats are limited, particularly when applied in conjunction with IRS and other adulticidal measures, such as the use of insecticide treated bednets.

Clinical classification of adult patients with chronic intestinal failure due to benign disease: An international multicenter cross-sectional survey.

PubMed

Pironi, Loris; Konrad, Denise; Brandt, Chrisoffer; Joly, Francisca; Wanten, Geert; Agostini, Federica; Chambrier, Cecile; Aimasso, Umberto; Zeraschi, Sarah; Kelly, Darlene; Szczepanek, Kinga; Jukes, Amelia; Di Caro, Simona; Theilla, Miriam; Kunecki, Marek; Daniels, Joanne; Serlie, Mireille; Poullenot, Florian; Wu, Jian; Cooper, Sheldon C; Rasmussen, Henrik H; Compher, Charlene; Seguy, David; Crivelli, Adriana; Pagano, Maria C; Hughes, Sarah-Jane; Guglielmi, Francesco W; Kozjek, Nada Rotovnik; Schneider, Stéphane M; Gillanders, Lyn; Ellegard, Lars; Thibault, Ronan; Matras, Przemysław; Zmarzly, Anna; Matysiak, Konrad; Van Gossum, Andrè; Forbes, Alastair; Wyer, Nicola; Taus, Marina; Virgili, Nuria M; O'Callaghan, Margie; Chapman, Brooke; Osland, Emma; Cuerda, Cristina; Sahin, Peter; Jones, Lynn; Lee, Andre D W; Bertasi, Valentino; Orlandoni, Paolo; Izbéki, Ferenc; Spaggiari, Corrado; Díez, Marta Bueno; Doitchinova-Simeonova, Maryana; Garde, Carmen; Serralde-Zúñiga, Aurora E; Olveira, Gabriel; Krznaric, Zeljko; Czako, Laszlo; Kekstas, Gintautas; Sanz-Paris, Alejandro; Jáuregui, Estrella Petrina; Murillo, Ana Zugasti; Schafer, Eszter; Arends, Jann; Suárez-Llanos, José P; Shaffer, Jon; Lal, Simon

2018-04-01

The aim of the study was to evaluate the applicability of the ESPEN 16-category clinical classification of chronic intestinal failure, based on patients' intravenous supplementation (IVS) requirements for energy and fluids, and to evaluate factors associated with those requirements. ESPEN members were invited to participate through ESPEN Council representatives. Participating centers enrolled adult patients requiring home parenteral nutrition for chronic intestinal failure on March 1st 2015. The following patient data were recorded though a structured database: sex, age, body weight and height, intestinal failure mechanism, underlying disease, IVS volume and energy need. Sixty-five centers from 22 countries enrolled 2919 patients with benign disease. One half of the patients were distributed in 3 categories of the ESPEN clinical classification. 9% of patients required only fluid and electrolyte supplementation. IVS requirement varied considerably according to the pathophysiological mechanism of intestinal failure. Notably, IVS volume requirement represented loss of intestinal function better than IVS energy requirement. A simplified 8 category classification of chronic intestinal failure was devised, based on two types of IVS (either fluid and electrolyte alone or parenteral nutrition admixture containing energy) and four categories of volume. Patients' IVS requirements varied widely, supporting the need for a tool to homogenize patient categorization. This study has devised a novel, simplified eight category IVS classification for chronic intestinal failure that will prove useful in both the clinical and research setting when applied together with the underlying pathophysiological mechanism of the patient's intestinal failure. Copyright © 2017 Elsevier Ltd and European Society for Clinical Nutrition and Metabolism. All rights reserved.

Maternal effects and larval survival of marbled sole Pseudopleuronectes yokohamae

NASA Astrophysics Data System (ADS)

Higashitani, Tomomi; Takatsu, Tetsuya; Nakaya, Mitsuhiro; Joh, Mikimasa; Takahashi, Toyomi

2007-07-01

Maternal effects of animals are the phenotypic influences of age, size, and condition of spawners on the survival and phenotypic traits of offspring. To clarify the maternal effects for marbled sole Pseudopleuronectes yokohamae, we investigated the effects of body size, nutrient condition, and growth history of adult females on egg size, larval size, and starvation tolerance, growth, and feeding ability of offspring. The fecundity of adult females was strongly dependent on body size. Path analysis revealed that the mother's total length positively affected mean egg diameter, meaning that large females spawned large eggs. In contrast, the relative growth rate of adult females negatively affected egg diameter. Egg diameters positively affected both notochord length and yolk sac volume of the larvae at hatching. Under starvation conditions, notochord length at hatching strongly and positively affected days of survival at 14 °C but not at 9 °C. Under adequate food conditions (1000 rotifers L - 1 ), the notochord length of larvae 5 days after hatching positively affected feeding rate, implying that large larvae have high feeding ability. In addition, the mean growth rate of larvae between 0 and 15 days increased with increasing egg diameter under homogenous food conditions, suggesting that larvae hatched from large eggs might have a growth advantage for at least to 15 days after hatching. In marbled sole, these relationships (i.e., mother's body size-egg size-larval size-larval resistance to starvation-larval feeding ability) may help explain recruitment variability.

LIN-23, an E3 Ubiquitin Ligase Component, Is Required for the Repression of CDC-25.2 Activity during Intestinal Development in Caenorhabditis elegans.

PubMed

Son, Miseol; Kawasaki, Ichiro; Oh, Bong-Kyeong; Shim, Yhong-Hee

2016-11-30

Caenorhabditis elegans ( C. elegans ) utilizes two different cell-cycle modes, binucleations during the L1 larval stage and endoreduplications at four larval moltings, for its postembryonic intestinal development. Previous genetic studies indicated that CDC-25.2 is specifically required for binucleations at the L1 larval stage and is repressed before endoreduplications. Furthermore, LIN-23, the C. elegans β-TrCP ortholog, appears to function as a repressor of CDC-25.2 to prevent excess intestinal divisions. We previously reported that intestinal hyperplasia in lin-23(e1883) mutants was effectively suppressed by the RNAi depletion of cdc-25.2 . Nevertheless, LIN-23 targeting CDC-25.2 for ubiquitination as a component of E3 ubiquitin ligase has not yet been tested. In this study, LIN-23 is shown to be the major E3 ubiquitin ligase component, recognizing CDC-25.2 to repress their activities for proper transition of cell-cycle modes during the C. elegans postembryonic intestinal development. In addition, for the first time that LIN-23 physically interacts with both CDC-25.1 and CDC-25.2 and facilitates ubiquitination for timely regulation of their activities during the intestinal development.

Soundscape manipulation enhances larval recruitment of a reef-building mollusk

PubMed Central

Bohnenstiehl, DelWayne R.; Eggleston, David B.

2015-01-01

Marine seafloor ecosystems, and efforts to restore them, depend critically on the influx and settlement of larvae following their pelagic dispersal period. Larval dispersal and settlement patterns are driven by a combination of physical oceanography and behavioral responses of larvae to a suite of sensory cues both in the water column and at settlement sites. There is growing evidence that the biological and physical sounds associated with adult habitats (i.e., the “soundscape”) influence larval settlement and habitat selection; however, the significance of acoustic cues is rarely tested. Here we show in a field experiment that the free-swimming larvae of an estuarine invertebrate, the eastern oyster, respond to the addition of replayed habitat-related sounds. Oyster larval recruitment was significantly higher on larval collectors exposed to oyster reef sounds compared to no-sound controls. These results provide the first field evidence that soundscape cues may attract the larval settlers of a reef-building estuarine invertebrate. PMID:26056624

Human intestinal anisakiosis due to consumption of raw salmon.

PubMed

Couture, Christian; Measures, Lena; Gagnon, Joël; Desbiens, Christine

2003-08-01

Anisakiosis is a parasitic infection that follows consumption of raw or insufficiently pickled, salted, smoked, or cooked wild marine fish infected with Anisakis sp. larvae. We report a case of intestinal anisakiosis in a 50-year-old man from Quebec who presented with abdominal pain and peripheral eosinophilia after eating raw wild-caught salmon from the Pacific Ocean off Canada. Abdominal CT scan showed bowel distension proximal to a segmental jejunal wall thickening, which was resected. The jejunum segment showed a localized area of serositis with mucosal edema and a submucosal abscess rich in eosinophils surrounding a parasite consistent with the third larval stage of Anisakis sp. Diagnostic morphologic characteristics included an unpaired excretory gland (renette cell), Y-shaped lateral epidermal cords, no apparent reproductive system, and a ventriculus (glandular esophagus). These features and the absence of lateral alae excluded Ascaris sp. The absence of ventricular appendage and intestinal cecum excluded other anisakids of the genera Pseudoterranova and Contracaecum. As the popularity of eating raw fish is growing in North America, anisakiosis may be diagnosed more frequently in surgical specimens. This parasitic infection should be considered in the differential diagnosis of acute abdominal syndromes and eosinophilic infiltrates of the stomach, small intestine, colon, omentum, and mesentery, especially with a history of raw marine fish consumption.

Requirement of matrix metalloproteinase-1 for intestinal homeostasis in the adult Drosophila midgut

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lee, Shin-Hae; Park, Joung-Sun; Kim, Young-Shin

Stem cells are tightly regulated by both intrinsic and extrinsic signals as well as the extracellular matrix (ECM) for tissue homeostasis and regenerative capacity. Matrix metalloproteinases (MMPs), proteolytic enzymes, modulate the turnover of numerous substrates, including cytokine precursors, growth factors, and ECM molecules. However, the roles of MMPs in the regulation of adult stem cells are poorly understood. In the present study, we utilize the Drosophila midgut, which is an excellent model system for studying stem cell biology, to show that Mmp1 is involved in the regulation of intestinal stem cells (ISCs). The results showed that Mmp1 is expressed inmore » the adult midgut and that its expression increases with age and with exposure to oxidative stress. Mmp1 knockdown or Timp-overexpressing flies and flies heterozygous for a viable, hypomorphic Mmp1 allele increased ISC proliferation in the gut, as shown by staining with an anti-phospho-histone H3 antibody and BrdU incorporation assays. Reduced Mmp1 levels induced intestinal hyperplasia, and the Mmp1depletion-induced ISC proliferation was rescued by the suppression of the EGFR signaling pathway, suggesting that Mmp1 regulates ISC proliferation through the EGFR signaling pathway. Furthermore, adult gut-specific knockdown and whole-animal heterozygotes of Mmp1 increased additively sensitivity to paraquat-induced oxidative stress and shortened lifespan. Our data suggest that Drosophila Mmp1 is involved in the regulation of ISC proliferation for maintenance of gut homeostasis. -- Highlights: Black-Right-Pointing-Pointer Mmp1 is expressed in the adult midgut. Black-Right-Pointing-Pointer Mmp1 is involved in the regulation of ISC proliferation activity. Black-Right-Pointing-Pointer Mmp1-related ISC proliferation is associated with EGFR signaling. Black-Right-Pointing-Pointer Mmp1 in the gut is required for the intestinal homeostasis and longevity.« less

Adaptation to new nutritional environments: larval performance, foraging decisions, and adult oviposition choices in Drosophila suzukii.

PubMed

Silva-Soares, Nuno F; Nogueira-Alves, A; Beldade, P; Mirth, Christen Kerry

2017-06-07

Understanding how species adapt to new niches is a central issue in evolutionary ecology. Nutrition is vital for the survival of all organisms and impacts species fitness and distribution. While most Drosophila species exploit rotting plant parts, some species have diversified to use ripe fruit, allowing earlier colonization. The decomposition of plant material is facilitated by yeast colonization and proliferation. These yeasts serve as the main protein source for Drosophila larvae. This dynamic rotting process entails changes in the nutritional composition of the food and other properties, and animals feeding on material at different stages of decay are expected to have behavioural and nutritional adaptations. We compared larval performance, feeding behaviour and adult oviposition site choice between the ripe fruit colonizer and invasive pest Drosophila suzukii, and a closely-related rotting fruit colonizer, Drosophila biarmipes. Through the manipulation of protein:carbohydrate ratios in artificial diets, we found that D. suzukii larvae perform better at lower protein concentrations and consume less protein rich diets relative to D. biarmipes. For adult oviposition, these species differed in preference for substrate hardness, but not for the substrate nutritional composition. Our findings highlight that rather than being an exclusive specialist on ripe fruit, D. suzukii's adaptation to use ripening fruit allow it to colonize a wider range of food substrates than D. biarmipes, which is limited to soft foods with higher protein concentrations. Our results underscore the importance of nutritional performance and feeding behaviours in the colonization of new food niches.

The Effect of Larval Diet on Adult Survival, Swarming Activity and Copulation Success in Male Aedes aegypti (Diptera: Culicidae).

PubMed

Lang, Bethan J; Idugboe, Stefano; McManus, Kirelle; Drury, Florence; Qureshi, Alima; Cator, Lauren J

2018-01-10

Control of Aedes aegypti (L.) (Diptera: Culicidae) populations is vital for reducing the transmission of several pervasive human diseases. The success of new vector control technologies will be influenced by the fitness of laboratory-reared transgenic males. However, there has been relatively little published data on how rearing practices influence male fitness in Aedes mosquitoes. In the laboratory, the effect of larval food availability on adult male fitness was tested, using a range of different fitness measures. Larval food availability was demonstrated to be positively correlated with adult body size. Larger males survived longer and exhibited greater swarming activity. As a consequence, larger males may have more mating opportunities in the wild. However, we also found that within a swarm larger males did not have an increased likelihood of copulating with a female. The outcome of the mating competition experiments depended on the methodology used to mark the males. These results show that fitness assessment can vary depending on the measure analyzed, and the methodology used to determine it. Continued investigation into these fitness measures and methodologies, and critically, their utility for predicting male performance in the field, will increase the efficiency of vector control programs. © The Author(s) 2017. Published by Oxford University Press on behalf of Entomological Society of America.

Larval traits carry over to affect post-settlement behaviour in a common coral reef fish.

PubMed

Dingeldein, Andrea L; White, J Wilson

2016-07-01

Most reef fishes begin life as planktonic larvae before settling to the reef, metamorphosing and entering the benthic adult population. Different selective forces determine survival in the planktonic and benthic life stages, but traits established in the larval stage may carry over to affect post-settlement performance. We tested the hypothesis that larval traits affect two key post-settlement fish behaviours: social group-joining and foraging. Certain larval traits of reef fishes are permanently recorded in the rings in their otoliths. In the bluehead wrasse (Thalassoma bifasciatum), prior work has shown that key larval traits recorded in otoliths (growth rate, energetic condition at settlement) carry over to affect post-settlement survival on the reef, with higher-larval-condition fish experiencing less post-settlement mortality. We hypothesized that this selective mortality is mediated by carry-over effects on post-settlement antipredator behaviours. We predicted that better-condition fish would forage less and be more likely to join groups, both behaviours that would reduce predation risk. We collected 550 recently settled bluehead wrasse (Thalassoma bifasciatum) from three reef sites off St. Croix (USVI) and performed two analyses. First, we compared each settler's larval traits to the size of its social group to determine whether larval traits influenced group-joining behaviour. Secondly, we observed foraging behaviour in a subset of grouped and solitary fish (n = 14) for 1-4 days post-settlement. We then collected the fish and tested whether larval traits influenced the proportion of time spent foraging. Body length at settlement, but not condition, affected group-joining behaviour; smaller fish were more likely to remain solitary or in smaller groups. However, both greater length and better condition were associated with greater proportions of time spent foraging over four consecutive days post-settlement. Larval traits carry over to affect post

In vitro cultivation of anisakis simplex: pepsin increases survival and moulting from fourth larval to adult stage.

PubMed

Iglesias, L; Valero, A; Benítez, R; Adroher, F J

2001-09-01

This paper describes the in vitro cultivation of the 3rd-larval stage (L3) of Anisakis simplex to adulthood in a much simpler and easier to prepare medium than those described to date. The adult males obtained are between 3.8 and 6.5 cm long and the females between 4.5 and 8.0 cm. Some individually cultivated females laid eggs which had an average size of 44.4 x 50.5 microm. The culture conditions were as follows: medium RPMI-1640 supplemented with 20% heat-inactivated fetal bovine serum and 1% commercial pepsin, at pH 4.0 and a temperature of 37 degrees C, and in air atmosphere with 5% CO2. The pepsin was found to be the key to the success of the culture. The average survival of the worms in the culture increased from 50 to 88 days, due to the fact that the survival of the adults practically doubled (increasing by 1.9 times). Furthermore, the number of worms that completed the 4th moulting (M4) increased by 4.2 times, from 22.9 to 95.6%. This culture medium may facilitate, due to its simplicity, the study of anisakids, or at least of A. simplex, constituting another step towards achieving a complete in vitro life-cycle for these parasites.

RNA-Seq Comparison of Larval and Adult Malpighian Tubules of the Yellow Fever Mosquito Aedes aegypti Reveals Life Stage-Specific Changes in Renal Function

PubMed Central

Li, Yiyi; Piermarini, Peter M.; Esquivel, Carlos J.; Drumm, Hannah E.; Schilkey, Faye D.; Hansen, Immo A.

2017-01-01

Introduction: The life history of Aedes aegypti presents diverse challenges to its diuretic system. During the larval and pupal life stages mosquitoes are aquatic. With the emergence of the adult they become terrestrial. This shifts the organism within minutes from an aquatic environment to a terrestrial environment where dehydration has to be avoided. In addition, female mosquitoes take large blood meals, which present an entirely new set of challenges to salt and water homeostasis. Methods: To determine differences in gene expression associated with these different life stages, we performed an RNA-seq analysis of the main diuretic tissue in A. aegypti, the Malpighian tubules. We compared transcript abundance in 4th instar larvae to that of adult females and analyzed the data with a focus on transcripts that encode proteins potentially involved in diuresis, like water and solute channels as well as ion transporters. We compared our results against the model of potassium- and sodium chloride excretion in the Malpighian tubules proposed by Hine et al. (2014), which involves at least eight ion transporters and a proton-pump. Results: We found 3,421 of a total number of 17,478 (19.6%) unique transcripts with a P < 0.05 and at least a 2.5 fold change in expression levels between the two groups. We identified two novel transporter genes that are highly expressed in the adult Malpighian tubules, which have not previously been part of the transport model in this species and may play important roles in diuresis. We also identified candidates for hypothesized sodium and chloride channels. Detoxification genes were generally higher expressed in larvae. Significance: This study represents the first comparison of Malpighian tubule transcriptomes between larval and adult A. aegypti mosquitoes, highlighting key differences in their renal systems that arise as they transform from an aquatic filter-feeding larval stage to a terrestrial, blood-feeding adult stage. PMID:28536536

Distributions of larval and juvenile/adult stages of the Antarctic myctophid fish, Electrona antarctica, off Wilkes Land in East Antarctica

NASA Astrophysics Data System (ADS)

Moteki, Masato; Fujii, Kentaro; Amakasu, Kazuo; Shimada, Keishi; Tanimura, Atsushi; Odate, Tsuneo

2017-06-01

Myctophid fish are an important component of the Southern Ocean food web because of their very high biomass. This study investigated the spatial distributions of larval and juvenile/adult stages of the Antarctic myctophid Electrona antarctica. Fish were sampled in January 2011 and 2012 on a transect along 140°E and in January 2013 along 110°E using two different opening/closing net systems. In total, 1075 specimens of E. antarctica were collected: 948 larvae, 127 juveniles/adults, and 2 in the transformation stage. Most larvae were collected at 5-200 m depth, with diel vertical migration (DVM) not apparent. Larvae were mainly distributed in the Modified Circumpolar Deep Water (-1.5 °C-2.0 °C). By contrast, an analysis of the echogram at 38 kHz and discrete depth samples implied that juveniles/adults undertook DVM except in the continental slope area (65.5°S). As the distribution of krill is limited to the cold water mass (<-1.5 °C) along the continental slope, E. antarctica and krill populations are spatially separated off Wilkes Land during summer. According to the previously estimated larval period of 30-47 days, E. antarctica may spawn in late November to December in the marginal ice zone or near the sea ice edge. This study suggests that the environment related to sea ice provides a nursery ground for early stage larvae of E. antarctica.

Determing Lamprey Species Composition, Larval Distribution, and Adult Abundance in the Deschutes River, Oregon, Subbasin; 2005-2006 Annual Report.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Graham, Jennifer C.; Brun, Christopher V.

2006-05-01

Information about lamprey species composition, distribution, life history, abundance, habitat requirements, and exploitation in the lower Deschutes River Subbasin is extremely limited. During 2002, we began a multi-year study to assess the status of lamprey in the Deschutes River subbasin. The objectives of this project are to determine ammocoete (larval lamprey) distribution and associated habitats; Lampretra species composition; numbers of emigrants; adult escapement and harvest rates at Sherars Falls. This report describes the preliminary results of data collected during 2005. We continued documenting ammocoete (larval) habitat selection by surveying four perennial eastside tributaries to the Deschutes River (Warm Springs River,more » Badger, Beaver and Shitike creeks) within the known ammocoete distribution. The results of 2003-2005 sampling indicate that positive relationships exist between: presence of wood (P = < 0.001), depositional area (P = < 0.001), flow (P = < 0.001), and fine substrate (P = < 0.001). Out-migrants numbers were not estimated during 2005 due to our inability to recapture marked larvae. In Shitike Creek, ammocoete and microphthalmia out-migration peaked during November 2005. In the Warm Spring River, out-migration peaked for ammocoetes in April 2006 and December 2005 for microphthalmia. Samples of ammocoetes from each stream were retained in a permanent collection of future analysis. An escapement estimate was generated for adult Pacific lamprey in the lower Deschutes River using a two event mark-recapture experiment during run year 2005. A modified Peterson model was used to estimate the adult population of Pacific lamprey at 3,895 with an estimated escapement of 2,881 during 2005 (95% CI= 2,847; M = 143; C = 1,027 R = 37). A tribal creel was also conducted from mid-June through August. We estimated tribal harvest to be approximately 1,015 adult lamprey during 2005 (95% CI= +/- 74).« less

Effect of cold storage on larval and adult Anastrepha ludens (Diptera: Tephritidae) viability in commercially ripe, artificially infested Persea americana 'Hass'.

PubMed

Aluja, M; Díaz-Fleischer, F; Arredondo, J; Valle-Mora, J; Rull, J

2010-12-01

Commercially ripe 'Hass' avocados, Persea americana Mill, artificially exposed to wild Anastrepha ludens (Loew) (Diptera: Tephritidae) females 24 h after harvest were placed in a cold storage facility to determine the effect of low temperature on larval survival and adult viability. Fruit were left for 3, 6, 9, and 12 d in a cold room at 5 degrees C followed by a 20-25-d period at ambient temperature to allow for larval development and pupation. Hass avocados and grapefruit, Citrus paradisi Macfadyen, maintained at ambient temperature served as controls. Overall, only 0.23% of the Hass avocados and 19.30% of the grapefruit were infested. The number of infested fruit increased with decreasing exposure time to cold. Puparia from cold-treated Hass avocados were significantly smaller than those stemming from cold-treated grapefruit. Hass avocados exposed for 12 d to 5 degrees C yielded no puparia, and those exposed for 6 and 9 d yielded 22 and two puparia, respectively, but no adults. Although Hass avocados exposed to cold temperature for 3 d yielded adults that reached sexual maturity (N = 16), females laid inviable eggs. Grapefruit exposed to cold for 12 d yielded normal-sized puparia (but no adults), whereas those exposed over 9 d yielded females able to lay viable eggs. We conclude that exposing fruit to cold storage after packing and during transport represents an effective risk-mitigating procedure in the highly improbable event that a gravid A. ludens female might lay eggs in a commercially ripe Hass avocado that had been left unprotected in a packinghouse.

Observations on the reproductive and larval biology of Blennius pavo (Pisces: Teleostei)

NASA Astrophysics Data System (ADS)

Westernhagen, H.

1983-09-01

Social behaviour and spawning of adult Blennius pavo kept in the laboratory are described. Eggs are deposited in batches on the walls of artificial spawning places (PVC pipes). One male guards and tends the eggs of different females in one spawning place. Larval hatching occurs in groups according to oviposition. Minimum incubation temperature is around 14 15°C. Larval survival in 1-1 rearing jars is not related to larval total length but to density of larval stock. An experimental population of laboratory reared juvenile and adolescent B. pavo displays a male to female ratio of 1:1.4. Factors possibly influencing the sex ratio of this littoral fish are discussed in view of the situation in its natural environment.

p53 is required for brain growth but is dispensable for resistance to nutrient restriction during Drosophila larval development

PubMed Central

Contreras, Esteban G.; Sierralta, Jimena

2018-01-01

Background Animal growth is influenced by the genetic background and the environmental circumstances. How genes promote growth and coordinate adaptation to nutrient availability is still an open question. p53 is a transcription factor that commands the cellular response to different types of stresses. In adult Drosophila melanogaster, p53 regulates the metabolic adaptation to nutrient restriction that supports fly viability. Furthermore, the larval brain is protected from nutrient restriction in a phenomenon called ‘brain sparing’. Therefore, we hypothesised that p53 may regulate brain growth and show a protective role over brain development under nutrient restriction. Results Here, we studied the function of p53 during brain growth in normal conditions and in animals subjected to developmental nutrient restriction. We showed that p53 loss of function reduced animal growth and larval brain size. Endogenous p53 was expressed in larval neural stem cells, but its levels and activity were not affected by nutritional stress. Interestingly, p53 knockdown only in neural stem cells was sufficient to decrease larval brain growth. Finally, we showed that in p53 mutant larvae under nutrient restriction, the energy storage levels were not altered, and these larvae generated adults with brains of similar size than wild-type animals. Conclusions Using genetic approaches, we demonstrate that p53 is required for proper growth of the larval brain. This developmental role of p53 does not have an impact on animal resistance to nutritional stress since brain growth in p53 mutants under nutrient restriction is similar to control animals. PMID:29621246

p53 is required for brain growth but is dispensable for resistance to nutrient restriction during Drosophila larval development.

PubMed

Contreras, Esteban G; Sierralta, Jimena; Glavic, Alvaro

2018-01-01

Animal growth is influenced by the genetic background and the environmental circumstances. How genes promote growth and coordinate adaptation to nutrient availability is still an open question. p53 is a transcription factor that commands the cellular response to different types of stresses. In adult Drosophila melanogaster, p53 regulates the metabolic adaptation to nutrient restriction that supports fly viability. Furthermore, the larval brain is protected from nutrient restriction in a phenomenon called 'brain sparing'. Therefore, we hypothesised that p53 may regulate brain growth and show a protective role over brain development under nutrient restriction. Here, we studied the function of p53 during brain growth in normal conditions and in animals subjected to developmental nutrient restriction. We showed that p53 loss of function reduced animal growth and larval brain size. Endogenous p53 was expressed in larval neural stem cells, but its levels and activity were not affected by nutritional stress. Interestingly, p53 knockdown only in neural stem cells was sufficient to decrease larval brain growth. Finally, we showed that in p53 mutant larvae under nutrient restriction, the energy storage levels were not altered, and these larvae generated adults with brains of similar size than wild-type animals. Using genetic approaches, we demonstrate that p53 is required for proper growth of the larval brain. This developmental role of p53 does not have an impact on animal resistance to nutritional stress since brain growth in p53 mutants under nutrient restriction is similar to control animals.

Effect of in ovo administration of an adult-derived microbiota on establishment of the intestinal microbiome in chickens.

PubMed

Pedroso, Adriana A; Batal, Amy B; Lee, Margie D

2016-05-01

OBJECTIVE To determine effects of in ovo administration of a probiotic on development of the intestinal microbiota of 2 genetic lineages (modern and heritage) of chickens. SAMPLE 10 newly hatched chicks and 40 fertile eggs to determine intestinal microbiota at hatch, 900 fertile eggs to determine effects of probiotic on hatchability, and 1,560 chicks from treated or control eggs. PROCEDURES A probiotic competitive-exclusion product derived from adult microbiota was administered in ovo to fertile eggs of both genetic lineages. Cecal contents and tissues were collected from embryos, newly hatched chicks, and chicks. A PCR assay was used to detect bacteria present within the cecum of newly hatched chicks. Fluorescence in situ hybridization and vitality staining were used to detect viable bacteria within intestines of embryos. The intestinal microbiota was assessed by use of 16S pyrosequencing. RESULTS Microscopic evaluation of embryonic cecal contents and tissues subjected to differential staining techniques revealed viable bacteria in low numbers. Development of the intestinal microbiota of broiler chicks of both genetic lineages was enhanced by in ovo administration of adult microbiota. Although the treatment increased diversity and affected composition of the microbiota of chicks, most bacterial species present in the probiotic were transient colonizers. However, the treatment decreased the abundance of undesirable bacterial species within heritage lineage chicks. CONCLUSIONS AND CLINICAL RELEVANCE In ovo inoculation of a probiotic competitive-exclusion product derived from adult microbiota may be a viable method of managing development of the microbiota and reducing the prevalence of pathogenic bacteria in chickens.

Nestin upregulation characterizes vascular remodeling secondary to hypertension in the rat.

PubMed

Tardif, Kim; Hertig, Vanessa; Duquette, Natacha; Villeneuve, Louis; El-Hamamsy, Ismail; Tanguay, Jean-François; Calderone, Angelino

2015-05-15

Proliferation and hypertrophy of vascular smooth muscle cells represent hallmark features of vessel remodeling secondary to hypertension. The intermediate filament protein nestin was recently identified in vascular smooth muscle cells and in other cell types directly participated in proliferation. The present study tested the hypothesis that vessel remodeling secondary to hypertension was characterized by nestin upregulation in vascular smooth muscle cells. Two weeks after suprarenal abdominal aorta constriction of adult male Sprague-Dawley rats, elevated mean arterial pressure increased the media area and thickness of the carotid artery and aorta and concomitantly upregulated nestin protein levels. In the normal adult rat carotid artery, nestin immunoreactivity was observed in a subpopulation of vascular smooth muscle cells, and the density significantly increased following suprarenal abdominal aorta constriction. Filamentous nestin was detected in cultured rat carotid artery- and aorta-derived vascular smooth muscle cells and an analogous paradigm observed in human aorta-derived vascular smooth muscle cells. ANG II and EGF treatment of vascular smooth muscle cells stimulated DNA and protein synthesis and increased nestin protein levels. Lentiviral short-hairpin RNA-mediated nestin depletion of carotid artery-derived vascular smooth muscle cells inhibited peptide growth factor-stimulated DNA synthesis, whereas protein synthesis remained intact. These data have demonstrated that vessel remodeling secondary to hypertension was characterized in part by nestin upregulation in vascular smooth muscle cells. The selective role of nestin in peptide growth factor-stimulated DNA synthesis has revealed that the proliferative and hypertrophic responses of vascular smooth muscle cells were mediated by divergent signaling events. Copyright © 2015 the American Physiological Society.

Do human activities influence survival and orientation abilities of larval fishes in the ocean?

PubMed

Siebeck, Ulrike E; O'Connor, Jack; Braun, Christoph; Leis, Jeffrey M

2015-01-01

The larval stages of most marine fishes spend days to weeks in the pelagic environment, where they must find food and avoid predators in order to survive. Some fish only spend part of their life history in the pelagic environment before returning to their adult habitat, for example, a coral reef. The sensory systems of larval fish develop rapidly during the first few days of their lives, and here we concentrate on the various sensory cues the fish have available to them for survival in the pelagic environment. We focus on the larvae of reef fishes because most is known about them. We also review the major threats caused by human activities that have been identified to have worldwide impact and evaluate how these threats may impact larval-fish survival and orientation abilities. Many human activities negatively affect larval-fish sensory systems or the cues the fish need to detect. Ultimately, this could lead to decreased numbers of larvae surviving to settlement, and, therefore, to decreased abundance of adult fishes. Although we focus on species wherein the larvae and adults occupy different habitats (pelagic and demersal, respectively), it is important to acknowledge that the potential anthropogenic effects we identify may also apply to larvae of species like tuna and herring, where both larvae and adults are pelagic. © 2014 International Society of Zoological Sciences, Institute of Zoology/Chinese Academy of Sciences and Wiley Publishing Asia Pty Ltd.

[Intestinal fungal diversity of sub-adult giant panda].

PubMed

Ai, Shengquan; Zhong, Zhijun; Peng, Guangneng; Wang, Chengdong; Luo, Yongjiu; He, Tingmei; Gu, Wuyang; Li, Caiwu; Li, Gangshi; Wu, Honglin; Liu, Xuehan; Xia, Yu; Liu, Yanhong; Zhou, Xiaoxiao

2014-11-04

The fungi diversity in the guts of five sub-adult giant pandas was analyzed. We analyzed the fungal internal transcribed spacer sequences (ITS) using restriction fragment length polymorphism (RFLP). ITS regions were amplified with fungal universal primers to construct ITS clone libraries. The fingerprints were analyzed by restriction fragment length polymorphism using the Hha I and Hae III enzymes. The cloned PCR products were analyzed by sequencing and diversities were demonstrated by phylogenetic tree. The gut fungi of 5 sub-adult giant pandas were mainly composed of Ascomycota (average of 46.24%), Basidiomycota ( average of 15.79%), unclassified (average of 29.14%), uncultured fungus (average of 8.83% ). Ascomycota was mainly composed of Saccharomycetes (average of 63.74%) and Dothideomycetes ( average of 35.91%); Basidiomycota was mainly composed of Tremellomycetes (average of 65.80%) and Microbotryomycetes (average of 33.15%). Four classes were mainly composed of Candida and Debaryomyces; Pleosporales and Myriangium; Cystofilobasidium and Trichosporon; Leucosporidium, and Leucosporidiella, whereas the proportions were different for each sample. Fungal flora existing in the intestines of sub-adult giant pandas expand our knowledge on the structure of the giant panda gut microbes and also help us to further study whether fungal flora can help giant pandas digest high-fiber foods.

Larval fish dynamics in spring pools in middle Tennessee

USGS Publications Warehouse

Bettoli, Phillip William; Goldsworthy, C.A.

2011-01-01

We used lighted larval traps to assess reproduction by fishes inhabiting nine spring pools in the Barrens Plateau region of middle Tennessee between May and September 2004. The traps (n = 162 deployments) captured the larval or juvenile forms of Etheostoma crossopterum (Fringed Darter) (n = 188), Gambusia affinis (Western Mosquitofish) (n = 139), Hemitremia flammea (Flame Chub) (n = 55), the imperiled Fundulus julisia (Barrens Topminnow) (n = 10), and Forbesichthys agassizii (Spring Cavefish) (n = 1). The larval forms of four other species (Families Centrarchidae, Cyprinidae, and Cottidae) were not collected, despite the presence of adults. Larval Barrens Topminnow hatched over a protracted period (early June through late September); in contrast, hatching intervals were much shorter for Fringed Darter (mid-May through early June). Flame Chub hatching began before our first samples in early May and concluded by late-May. Juvenile Western Mosquitofish were collected between early June and late August. Our sampling revealed that at least two species (Flame Chub and Fringed Darter) were able to reproduce and recruit in habitats harboring the invasive Western Mosquitofish, while Barrens Topminnow could not.

Social coercion of larval development in an ant species

NASA Astrophysics Data System (ADS)

Villalta, Irene; Amor, Fernando; Cerdá, Xim; Boulay, Raphaël

2016-04-01

Ants provide one of the best examples of the division of labor in animal societies. While the queens reproduce, workers generally refrain from laying eggs and dedicate themselves exclusively to domestic tasks. In many species, the small diploid larvae are bipotent and can develop either into workers or queens depending mostly on environmental cues. This generates a conflicting situation between the adults that tend to rear a majority of larvae into workers and the larvae whose individual interest may be to develop into reproductive queens. We tested the social regulation of larval caste fate in the fission-performing ant Aphaenogaster senilis. We first observed interactions between resident workers and queen- and worker-destined larvae in presence/absence of the queen. The results show that workers tend to specifically eliminate queen-destined larvae when the queen is present but not when she is absent or imprisoned in a small cage allowing for volatile pheromone exchanges. In addition, we found that the presence of already developed queen-destined larvae does not inhibit the development of younger still bipotent larvae into queens. Finally, we analyzed the cuticular hydrocarbon profiles of queen- and worker-destined larvae and found no significant quantitative or qualitative difference. Interestingly, the total amount of hydrocarbons on both larval castes is extremely low, which lends credence on the chemical insignificance hypothesis of larval ants. Overall, our results suggest that workers control larval development and police larvae that would develop into queens instead of workers. Such policing behavior is similar in many aspects to what is known of worker policing among adults.

Social coercion of larval development in an ant species.

PubMed

Villalta, Irene; Amor, Fernando; Cerdá, Xim; Boulay, Raphaël

2016-04-01

Ants provide one of the best examples of the division of labor in animal societies. While the queens reproduce, workers generally refrain from laying eggs and dedicate themselves exclusively to domestic tasks. In many species, the small diploid larvae are bipotent and can develop either into workers or queens depending mostly on environmental cues. This generates a conflicting situation between the adults that tend to rear a majority of larvae into workers and the larvae whose individual interest may be to develop into reproductive queens. We tested the social regulation of larval caste fate in the fission-performing ant Aphaenogaster senilis. We first observed interactions between resident workers and queen- and worker-destined larvae in presence/absence of the queen. The results show that workers tend to specifically eliminate queen-destined larvae when the queen is present but not when she is absent or imprisoned in a small cage allowing for volatile pheromone exchanges. In addition, we found that the presence of already developed queen-destined larvae does not inhibit the development of younger still bipotent larvae into queens. Finally, we analyzed the cuticular hydrocarbon profiles of queen- and worker-destined larvae and found no significant quantitative or qualitative difference. Interestingly, the total amount of hydrocarbons on both larval castes is extremely low, which lends credence on the chemical insignificance hypothesis of larval ants. Overall, our results suggest that workers control larval development and police larvae that would develop into queens instead of workers. Such policing behavior is similar in many aspects to what is known of worker policing among adults.

Composition, diversity and function of intestinal microbiota in pacific white shrimp (Litopenaeus vannamei) at different culture stages.

PubMed

Zeng, Shenzheng; Huang, Zhijian; Hou, Dongwei; Liu, Jian; Weng, Shaoping; He, Jianguo

2017-01-01

Intestinal microbiota is an integral component of the host and plays important roles in host health. The pacific white shrimp is one of the most profitable aquaculture species commercialized in the world market with the largest production in shrimp consumption. Many studies revealed that the intestinal microbiota shifted significantly during host development in other aquaculture animals. In the present study, 22 shrimp samples were collected every 15 days from larval stage (15 day post-hatching, dph) to adult stage (75 dph) to investigate the intestinal microbiota at different culture stages by targeting the V4 region of 16S rRNA gene, and the microbial function prediction was conducted by PICRUSt. The operational taxonomic unit (OTU) was assigned at 97% sequence identity. A total of 2,496 OTUs were obtained, ranging from 585 to 1,239 in each sample. Forty-three phyla were identified due to the classifiable sequence. The most abundant phyla were Proteobacteria, Cyanobacteria, Tenericutes, Fusobacteria, Firmicutes, Verrucomicrobia, Bacteroidetes, Planctomycetes, Actinobacteria and Chloroflexi. OTUs belonged to 289 genera and the most abundant genera were Candidatus_Xiphinematobacter , Propionigenium , Synechococcus , Shewanella and Cetobacterium . Fifty-nine OTUs were detected in all samples, which were considered as the major microbes in intestine of shrimp. The intestinal microbiota was enriched with functional potentials that were related to transporters, ABC transporters, DNA repair and recombination proteins, two component system, secretion system, bacterial motility proteins, purine metabolism and ribosome. All the results showed that the intestinal microbial composition, diversity and functions varied significantly at different culture stages, which indicated that shrimp intestinal microbiota depended on culture stages. These findings provided new evidence on intestinal microorganism microecology and greatly enhanced our understanding of stage

Cocoa-enriched diets modulate intestinal and systemic humoral immune response in young adult rats.

PubMed

Pérez-Berezo, Teresa; Franch, Angels; Ramos-Romero, Sara; Castellote, Cristina; Pérez-Cano, Francisco J; Castell, Margarida

2011-05-01

Previous studies have shown that a highly enriched cocoa diet affects both intestinal and systemic immune function in young rats. The aim of this study was to elucidate whether diets containing lower amounts of cocoa could also influence the systemic and intestinal humoral immune response. Fecal and serum samples were collected during the study and, at the end, intestinal washes were obtained and mesenteric lymph nodes and small-intestine walls were excised for gene expression assessment. IgA, IgM, IgG1, IgG2a, IgG2b and IgG2c concentrations were quantified in serum whereas S-IgA and S-IgM were determined in feces and intestinal washes. Animals receiving 5 and 10% cocoa for 3 wk showed no age-related increase in serum IgG1 and IgG2a concentrations, and IgG2a values were significantly lower than those in reference animals. Serum IgM was also decreased by the 10% cocoa diet. The 5 and 10% cocoa diets dramatically reduced intestinal S-IgA concentration and modified the expression of several genes involved in IgA synthesis. A diet containing 2% cocoa had no effect on most of the studied variables. The results demonstrate the downregulatory effect of a 5% or higher cocoa diet on the systemic and intestinal humoral immune response in adult rats. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Larval exposure to azadirachtin affects fitness and oviposition site preference of Drosophila melanogaster.

PubMed

Bezzar-Bendjazia, Radia; Kilani-Morakchi, Samira; Aribi, Nadia

2016-10-01

Azadirachtin, a biorational insecticide, is one of the prominent biopesticide commercialized today and represent an alternative to conventional insecticides. The current study examined the lethal and sublethal effects of azadirachtin on Drosophila melanogaster Meigen, 1830 (Diptera: Drosophilidae) as biological model. Various doses ranging from 0.1 to 2μg were applied topically on early third instar larvae and the cumulative mortality of immature stage was determined. In second series of experiments, azadirachtin was applied at its LD 25 (0.28μg) and LD 50 (0.67μg) and evaluated on fitness (development duration, fecundity, adult survival) and oviposition site preference with and without choice. Results showed that azadirachtin increased significantly at the two tested doses the duration of larval and pupal development. Moreover, azadirachtin treatment reduced significantly adult's survival of both sex as compared to control. In addition, azadirachtin affected fecundity of flies by a significant reduction of the number of eggs laid. Finally results showed that females present clear preference for oviposition in control medium. Pre-imaginal exposure (L3) to azadirachtin increased aversion to this substance suggesting a memorability of the learned avoidance. The results provide some evidence that larval exposure to azadirachtin altered adult oviposition preference as well as major fitness traits of D. melanogaster. Theses finding may reinforce behavioural avoidance of azadirachtin and contribute as repellent strategies in integrated pest management programmes. Copyright © 2016 Elsevier B.V. All rights reserved.

Transport of particles in intestinal mucus under simulated infant and adult physiological conditions: impact of mucus structure and extracellular DNA.

PubMed

Macierzanka, Adam; Mackie, Alan R; Bajka, Balazs H; Rigby, Neil M; Nau, Françoise; Dupont, Didier

2014-01-01

The final boundary between digested food and the cells that take up nutrients in the small intestine is a protective layer of mucus. In this work, the microstructural organization and permeability of the intestinal mucus have been determined under conditions simulating those of infant and adult human small intestines. As a model, we used the mucus from the proximal (jejunal) small intestines of piglets and adult pigs. Confocal microscopy of both unfixed and fixed mucosal tissue showed mucus lining the entire jejunal epithelium. The mucus contained DNA from shed epithelial cells at different stages of degradation, with higher amounts of DNA found in the adult pig. The pig mucus comprised a coherent network of mucin and DNA with higher viscosity than the more heterogeneous piglet mucus, which resulted in increased permeability of the latter to 500-nm and 1-µm latex beads. Multiple-particle tracking experiments revealed that diffusion of the probe particles was considerably enhanced after treating mucus with DNase. The fraction of diffusive 500-nm probe particles increased in the pig mucus from 0.6% to 64% and in the piglet mucus from ca. 30% to 77% after the treatment. This suggests that extracellular DNA can significantly contribute to the microrheology and barrier properties of the intestinal mucus layer. To our knowledge, this is the first time that the structure and permeability of the small intestinal mucus have been compared between different age groups and the contribution of extracellular DNA highlighted. The results help to define rules governing colloidal transport in the developing small intestine. These are required for engineering orally administered pharmaceutical preparations with improved delivery, as well as for fabricating novel foods with enhanced nutritional quality or for controlled calorie uptake.

Bacterial microbiota assemblage in Aedes albopictus mosquitoes and its impacts on larval development.

PubMed

Wang, Xiaoming; Liu, Tong; Wu, Yang; Zhong, Daibin; Zhou, Guofa; Su, Xinghua; Xu, Jiabao; Sotero, Charity F; Sadruddin, Adnan A; Wu, Kun; Chen, Xiao-Guang; Yan, Guiyun

2018-05-30

Interactions between bacterial microbiota and mosquitoes play an important role in mosquitoes' capacity to transmit pathogens. However, microbiota assemblages within mosquitoes and the impact of microbiota in environments on mosquito development and survival remain unclear. This study examined microbiota assemblages and the effects of aquatic environment microbiota on the larval development of the Aedes albopictus mosquito, an important dengue virus vector. Life table studies have found that reducing bacterial load in natural aquatic habitats through water filtering and treatment with antibiotics significantly reduced the larva-to-adult emergence rate. This finding was consistent in two types of larval habitats examined-discarded tires and flowerpots, suggesting that bacteria play a crucial role in larval development. Pyrosequencing of the bacterial 16S rRNA gene was used to determine the diversity of bacterial communities in larval habitats and the resulting numbers of mosquitoes under both laboratory and field conditions. The microbiota profiling identified common shared bacteria among samples from different years; further studies are needed to determine whether these bacteria represent a core microbiota. The highest microbiota diversity was found in aquatic habitats, followed by mosquito larvae, and the lowest in adult mosquitoes. Mosquito larvae ingested their bacterial microbiota and nutrients from aquatic habitats of high microbiota diversity. Taken together, the results support the observation that Ae. albopictus larvae are able to utilize diverse bacteria from aquatic habitats and that live bacteria from aquatic habitats play an important role in larval mosquito development and survival. These findings provide new insights into bacteria's role in mosquito larval ecology. © 2018 John Wiley & Sons Ltd.

Starvation stress during larval development facilitates an adaptive response in adult worker honey bees (Apis mellifera L.).

PubMed

Wang, Ying; Kaftanoglu, Osman; Brent, Colin S; Page, Robert E; Amdam, Gro V

2016-04-01

Most organisms are constantly faced with environmental changes and stressors. In diverse organisms, there is an anticipatory mechanism during development that can program adult phenotypes. The adult phenotype would be adapted to the predicted environment that occurred during organism maturation. However, whether this anticipatory mechanism is present in eusocial species is questionable because eusocial organisms are largely shielded from exogenous conditions by their stable nest environment. In this study, we tested whether food deprivation during development of the honey bee (Apis mellifera), a eusocial insect model, can shift adult phenotypes to better cope with nutritional stress. After subjecting fifth instar worker larvae to short-term starvation, we measured nutrition-related morphology, starvation resistance, physiology, endocrinology and behavior in the adults. We found that the larval starvation caused adult honey bees to become more resilient toward starvation. Moreover, the adult bees were characterized by reduced ovary size, elevated glycogen stores and juvenile hormone (JH) titers, and decreased sugar sensitivity. These changes, in general, can help adult insects survive and reproduce in food-poor environments. Overall, we found for the first time support for an anticipatory mechanism in a eusocial species, the honey bee. Our results suggest that this mechanism may play a role in honey bee queen-worker differentiation and worker division of labor, both of which are related to the responses to nutritional stress. © 2016. Published by The Company of Biologists Ltd.

Lead Poisoning in Remodeling of Old Homes

ERIC Educational Resources Information Center

Barnes, Bart

1973-01-01

An article based on Dr. Muriel D. Wolf's study of elevated blood lead levels in children and adults present during the remodeling of old homes. Lead poisoning examples, symptoms, and precautions are given. (ST)

Maintenance of the adult Drosophila intestine: all roads lead to homeostasis.

PubMed

Guo, Zheng; Lucchetta, Elena; Rafel, Neus; Ohlstein, Benjamin

2016-10-01

Maintenance of tissue homeostasis is critical in tissues with high turnover such as the intestinal epithelium. The intestinal epithelium is under constant cellular assault due to its digestive functions and its function as a barrier to chemical and bacterial insults. The resulting high rate of cellular turnover necessitates highly controlled mechanisms of regeneration to maintain the integrity of the tissue over the lifetime of the organism. Transient increase in stem cell proliferation is a commonly used and elaborate mechanism to ensure fast and efficient repair of the gut. However, tissue repair is not limited to regulating ISC proliferation, as emerging evidence demonstrates that the Drosophila intestine uses multiple strategies to ensure proper tissue homeostasis that may also extend to other tissues. Copyright © 2016 Elsevier Ltd. All rights reserved.

Elevated Markers of Vascular Remodeling and Arterial Stiffness Are Associated with Neurocognitive Function in Older HIV+ Adults on Suppressive Antiretroviral Therapy

PubMed Central

Montoya, Jessica L.; Iudicello, Jennifer; Fazeli, Pariya L.; Hong, Suzi; Potter, Michael; Ellis, Ronald J.; Grant, Igor; Letendre, Scott L.; Moore, David J.

2016-01-01

Background HIV is associated with elevated markers of vascular remodeling that may contribute to arterial fibrosis and stiffening, and changes in pulse pressure (PP). These changes may, in turn, deleteriously affect autoregulation of cerebral blood flow and neurocognitive function. Methods To evaluate these mechanisms, we studied markers of vascular remodeling, PP, and neurocognitive function among older (≥50 years of age) HIV-infected (HIV+; n = 72) and HIV-seronegative (HIV-; n = 36) adults. Participants completed standardized neurobehavioral and neuromedical assessments. Neurocognitive functioning was evaluated using a well-validated comprehensive battery. Three plasma biomarkers of vascular remodeling (i.e., angiopoietin 2, Tie-2, and vascular endothelial growth factor; VEGF) were collected. Results HIV+ and HIV- participants had similar levels of plasma Ang-2 (p = .48), Tie-2 (p = .27), VEGF (p = .18), and PP (p = .98). In a multivariable regression model, HIV interacted with Tie-2 (β = .41, p < .01) and VEGF (β = −.43, p = .01) on neurocognitive function, such that lower Tie-2 and higher VEGF values were associated with worse neurocognitive function for HIV+ participants. Greater Tie-2 values were associated with increased PP (r = .31, p < .01). In turn, PP demonstrated a quadratic association with neurocognitive function (β = −.33, p = .01), such that lower and higher, relative to mean sample, PP values were associated with worse neurocognitive function. Conclusions These findings indicate that vascular remodeling and altered cerebral blood flow autoregulation contribute to neurocognitive function. Furthermore, HIV moderates the association between vascular remodeling and neurocognitive function but not the association between PP and neurocognitive function. PMID:27828873

BDNF Expression in Larval and Adult Zebrafish Brain: Distribution and Cell Identification

PubMed Central

Cacialli, Pietro; Gueguen, Marie-Madeleine; Coumailleau, Pascal; D’Angelo, Livia; Kah, Olivier; Lucini, Carla; Pellegrini, Elisabeth

2016-01-01

Brain-derived neurotrophic factor (BDNF), a member of the neurotrophin family, has emerged as an active mediator in many essential functions in the central nervous system of mammals. BDNF plays significant roles in neurogenesis, neuronal maturation and/or synaptic plasticity and is involved in cognitive functions such as learning and memory. Despite the vast literature present in mammals, studies devoted to BDNF in the brain of other animal models are scarse. Zebrafish is a teleost fish widely known for developmental genetic studies and is emerging as model for translational neuroscience research. In addition, its brain shows many sites of adult neurogenesis allowing higher regenerative properties after traumatic injuries. To add further knowledge on neurotrophic factors in vertebrate brain models, we decided to determine the distribution of bdnf mRNAs in the larval and adult zebrafish brain and to characterize the phenotype of cells expressing bdnf mRNAs by means of double staining studies. Our results showed that bdnf mRNAs were widely expressed in the brain of 7 days old larvae and throughout the whole brain of mature female and male zebrafish. In adults, bdnf mRNAs were mainly observed in the dorsal telencephalon, preoptic area, dorsal thalamus, posterior tuberculum, hypothalamus, synencephalon, optic tectum and medulla oblongata. By combining immunohistochemistry with in situ hybridization, we showed that bdnf mRNAs were never expressed by radial glial cells or proliferating cells. By contrast, bdnf transcripts were expressed in cells with neuronal phenotype in all brain regions investigated. Our results provide the first demonstration that the brain of zebrafish expresses bdnf mRNAs in neurons and open new fields of research on the role of the BDNF factor in brain mechanisms in normal and brain repairs situations. PMID:27336917

Jaw muscle development as evidence for embryonic repatterning in direct-developing frogs.

PubMed Central

Hanken, J; Klymkowsky, M W; Alley, K E; Jennings, D H

1997-01-01

The Puerto Rican direct-developing frog Eleutherodactylus coqui (Leptodactylidae) displays a novel mode of jaw muscle development for anuran amphibians. Unlike metamorphosing species, several larval-specific features never form in E. coqui; embryonic muscle primordia initially assume an abbreviated, mid-metamorphic configuration that is soon remodelled to form the adult morphology before hatching. Also lacking are both the distinct population of larval myofibres and the conspicuous, larval-to-adult myofibre turnover that are characteristic of muscle development in metamorphosing species. These modifications are part of a comprehensive alteration in embryonic cranial patterning that has accompanied life history evolution in this highly speciose lineage. Embryonic 'repatterning' in Eleutherodactylus may reflect underlying developmental mechanisms that mediate the integrated evolution of complex structures. Such mechanisms may also facilitate, in organisms with a primitively complex life cycle, the evolutionary dissociation of embryonic, larval, and adult features. PMID:9332017

Larval Competition Reduces Body Condition in the Female Seed Beetle, Callosobruchus maculatus

PubMed Central

Schade, Daynika J.; Vamosi, Steven M.

2012-01-01

Early body condition may be important for adult behavior and fitness, and is impacted by a number of environmental conditions and biotic interactions. Reduced fecundity of adult females exposed to larval competition may be caused by reduced body condition or shifts in relative body composition, yet these mechanisms have not been well researched. Here, body mass, body size, scaled body mass index, and two body components (water content and lean dry mass) of adult Callosobruchus maculatus (Fabricius) (Coleoptera: Chrysomelidae: Bruchinae) females exposed to larval competition or reared alone were examined. Experimental females emerged at significantly smaller body mass and body size than control females. Additionally, scaled body mass index and water content, but not lean dry mass, were significantly reduced in experimental females. To our knowledge, these are the first results that demonstrate a potential mechanism for previously documented direct effects of competition on fecundity in female bruchine beetles. PMID:22954282

Larval competition reduces body condition in the female seed beetle, Callosobruchus maculatus.

PubMed

Schade, Daynika J; Vamosi, Steven M

2012-01-01

Early body condition may be important for adult behavior and fitness, and is impacted by a number of environmental conditions and biotic interactions. Reduced fecundity of adult females exposed to larval competition may be caused by reduced body condition or shifts in relative body composition, yet these mechanisms have not been well researched. Here, body mass, body size, scaled body mass index, and two body components (water content and lean dry mass) of adult Callosobruchus maculatus (Fabricius) (Coleoptera: Chrysomelidae: Bruchinae) females exposed to larval competition or reared alone were examined. Experimental females emerged at significantly smaller body mass and body size than control females. Additionally, scaled body mass index and water content, but not lean dry mass, were significantly reduced in experimental females. To our knowledge, these are the first results that demonstrate a potential mechanism for previously documented direct effects of competition on fecundity in female bruchine beetles.

Dissection and staining of Drosophila larval ovaries.

PubMed

Maimon, Iris; Gilboa, Lilach

2011-05-13

Many organs depend on stem cells for their development during embryogenesis and for maintenance or repair during adult life. Understanding how stem cells form, and how they interact with their environment is therefore crucial for understanding development, homeostasis and disease. The ovary of the fruit fly Drosophila melanogaster has served as an influential model for the interaction of germ line stem cells (GSCs) with their somatic support cells (niche) (1, 2). The known location of the niche and the GSCs, coupled to the ability to genetically manipulate them, has allowed researchers to elucidate a variety of interactions between stem cells and their niches (3-12). Despite the wealth of information about mechanisms controlling GSC maintenance and differentiation, relatively little is known about how GSCs and their somatic niches form during development. About 18 somatic niches, whose cellular components include terminal filament and cap cells (Figure 1), form during the third larval instar (13-17). GSCs originate from primordial germ cells (PGCs). PGCs proliferate at early larval stages, but following the formation of the niche a subgroup of PGCs becomes GSCs (7, 16, 18, 19). Together, the somatic niche cells and the GSCs make a functional unit that produces eggs throughout the lifetime of the organism. Many questions regarding the formation of the GSC unit remain unanswered. Processes such as coordination between precursor cells for niches and stem cell precursors, or the generation of asymmetry within PGCs as they become GSCs, can best be studied in the larva. However, a methodical study of larval ovary development is physically challenging. First, larval ovaries are small. Even at late larval stages they are only 100μm across. In addition, the ovaries are transparent and are embedded in a white fat body. Here we describe a step-by-step protocol for isolating ovaries from late third instar (LL3) Drosophila larvae, followed by staining with fluorescent

Revision of the genus Dinotoperla Tillyard, 1921 (Plecoptera: Gripopterygidae) using morphological characters and molecular data: Establishes two new genera, three new species and updates the larval taxonomy.

PubMed

Mynott, Julia H; Suter, Phillip J; Theischinger, Gunther

2017-01-23

The larval taxonomy of Australian stoneflies (Plecoptera) shows a large disparity in knowledge when compared to the adult taxonomy with many species having undescribed larval forms. The importance of stoneflies as an indicator group for monitoring aquatic ecosystems means knowledge of the larval taxonomy and the ability to identify species is essential. This study combined morphology and mitochondrial gene sequences to associate the adult and larval life-stages for species of Dinotoperla Tillyard. Morphological identification of adult males was recognised for 17 of the 35 Dinotoperla species and combining molecular data with morphology confirmed eight new adult-larval life stage associations. Further, molecular data supported the larval taxonomy for five morphospecies which remain unassociated. The combination of molecular and morphological methods enabled the larval morphology to be reassessed for the genus Dinotoperla and this has led to the establishment of two new genera, Odontoperla, gen. nov. and Oedemaperla, gen. nov., and the new species Dinotoperla aryballoi, sp. nov, D. tasmaniensis, sp. nov. and Oedemaperla shackletoni, sp. nov. as well as the new or updated descriptions of the larvae of 31 species and a comprehensive dichotomous key to these larvae.

Fisheries Closed Areas Strengthen Scallop Larval Settlement and Connectivity Among Closed Areas and Across International Open Fishing Grounds: A Model Study.

PubMed

Davies, Kimberley T A; Gentleman, W C; DiBacco, C; Johnson, C L

2015-09-01

This study examined whether a measured increase in average body size of adult sea scallops inside three fishery closed areas on Georges Bank (GB), United States (US), was sufficient to increase larval supply to closed areas and open fishing areas in both US and Canadian areas of the Bank. The effects of adult scallop density-at-size and fecundity-at-size on egg production were compared among open and closed fishery areas, countries, and time periods before and after the closed areas were established. Estimated egg production was then used to define spawning conditions in a coupled biological-physical larval tracking model that simulated larval development, mortality, and dispersal. Results showed that order of magnitude increases in larval settlement after closure were facilitated by increases in size-dependant egg production inside and dispersal from Closed Areas I and II, but not Nantucket Lightship Closed Area. The distributions of both egg production and larval settlement became more uniform across the Bank, causing the relative contribution of Canadian larvae to US scallop aggregations to decrease after establishment of Closed Areas I and II. Decreases in small and medium-sized scallop density in Canada and decreases in large scallops over the US-Southern Flank after closure caused local declines in egg production but were not sufficient to negatively affect larval settlement at the regional scale. Our model suggests that the establishment of fishery closed areas on GB considerably strengthened larval supply and settlement within and among several adult scallop aggregations.

Fisheries Closed Areas Strengthen Scallop Larval Settlement and Connectivity Among Closed Areas and Across International Open Fishing Grounds: A Model Study

NASA Astrophysics Data System (ADS)

Davies, Kimberley T. A.; Gentleman, W. C.; DiBacco, C.; Johnson, C. L.

2015-09-01

This study examined whether a measured increase in average body size of adult sea scallops inside three fishery closed areas on Georges Bank (GB), United States (US), was sufficient to increase larval supply to closed areas and open fishing areas in both US and Canadian areas of the Bank. The effects of adult scallop density-at-size and fecundity-at-size on egg production were compared among open and closed fishery areas, countries, and time periods before and after the closed areas were established. Estimated egg production was then used to define spawning conditions in a coupled biological-physical larval tracking model that simulated larval development, mortality, and dispersal. Results showed that order of magnitude increases in larval settlement after closure were facilitated by increases in size-dependant egg production inside and dispersal from Closed Areas I and II, but not Nantucket Lightship Closed Area. The distributions of both egg production and larval settlement became more uniform across the Bank, causing the relative contribution of Canadian larvae to US scallop aggregations to decrease after establishment of Closed Areas I and II. Decreases in small and medium-sized scallop density in Canada and decreases in large scallops over the US-Southern Flank after closure caused local declines in egg production but were not sufficient to negatively affect larval settlement at the regional scale. Our model suggests that the establishment of fishery closed areas on GB considerably strengthened larval supply and settlement within and among several adult scallop aggregations.

Co-infection of intestinal parasites and Helicobacter pylori among upper gastrointestinal symptomatic adult patients attending Mekanesalem Hospital, northeast Ethiopia.

PubMed

Seid, Abdurahaman; Tamir, Zemenu; Kasanew, Brhanu; Senbetay, Moges

2018-02-20

Intestinal parasites and H. pylori are well-known for their high prevalence worldwide. Thus, the objective of this study waste assess risk factors and co-infection of intestinal parasites and H. pylori among adult patients with upper gastrointestinal complaints. A hospital-based cross sectional study was conducted among 363 consecutive adult patients from December 10, 2015 to February 30,2016. Stool and venous blood were collected for analysis of Intestinal parasites and H. pylori infection, respectively. Data was analyzed using SPSS version 16 and logistic regression analysis was carried out to assess predictors of co-infection. A p ≤ 0.05 was considered as statistically significant. Helicobacter pylori IgG and intestinal parasites were detected in 70.25-38.3% of participants, respectively while G. lamblia accounted 22.3%. G. lamblia prevalence was significantly higher among H. pylori infected participants (COR: 2.76; 95% CI: 1.46-5.23), but E. hystolytica/dispar infection didn't show significant variation (p = 0.15). H. pylori and intestinal parasites concomitant co-infection was associated with male sex (AOR: 1.61; 95% CI: 1.01-2.56), consumption of river water (AOR: 1.85; 95% CI: 1.11-3.07) and ground/spring water (AOR: 4.10; 95% CI: 1.97-8.52). Thus, besides H. pylori investigation, upper gastrointestinal symptomatic patients should be screened for G. lamblia infection and other intestinal parasites.

Hydrodynamics of larval settlement: The influence of turbulent stress events at potential recruitment sites

USGS Publications Warehouse

Crimaldi, John P.; Thompson, Janet K.; Rosman, Johanna H.; Lowe, Ryan J.; Koseff, Jeffrey R.

2002-01-01

We describe a laboratory investigation into the effect of turbulent hydrodynamic stresses on clam larvae in the settlement phase of the recruitment process. A two-component laser-Doppler anemometer (LDA) was used to measure time histories of the instantaneous turbulence structure at potential recruitment sites within reconstructed beds of the adult Asian clam, Potamocorbula amurensis. Measurements were made for two flow speeds over beds with three different clam densities and two different clam heights. We analyze the statistical effect of the turbulence on the larval flux to the bed and on the probability of successful anchoring to the substrate. It is shown that the anchoring probability depends on the nature of the instantaneous stress events rather than on mean stresses. The instantaneous turbulence structure near the bed is altered by the flow rate and the spacing and height of adult clams living in the substrate. The ability to anchor quickly is therefore extremely important, since the time sequence of episodic turbulent stress events influences larval settlement success. The probability of successful larval settlement is predicted to decrease as the spacing between adults decreases, implying that the hydrodynamics impose negative feedback on clam bed aggregation dynamics.

The midgut of the silkmoth Bombyx mori is able to recycle molecules derived from degeneration of the larval midgut epithelium.

PubMed

Franzetti, Eleonora; Romanelli, Davide; Caccia, Silvia; Cappellozza, Silvia; Congiu, Terenzio; Rajagopalan, Muthukumaran; Grimaldi, Annalisa; de Eguileor, Magda; Casartelli, Morena; Tettamanti, Gianluca

2015-08-01

The midgut represents the middle part of the alimentary canal and is responsible for nutrient digestion and absorption in insect larva. Despite the growing interest in this organ for different purposes, such as studies on morphogenesis and differentiation, stem cell biology, cell death processes and transport mechanisms, basic information on midgut development is still lacking for a large proportion of insect species. Undoubtedly, this lack of data could hinder the full exploitation of practical applications that involve midgut as their primary target. This may represent in particular a significant problem for Lepidoptera, an insect order that includes some of the most important species of high economic importance. With the aim of overcoming this fragmentation of knowledge, we performed a detailed morphofunctional analysis of the midgut of the silkworm, Bombyx mori, a representative model among Lepidoptera, during its development from the larval up to the adult stage, focusing attention on stem cells. Our data demonstrate stem cell proliferation and differentiation, not only in the larval midgut but also in the pupal and adult midgut epithelium. Moreover, we present evidence for a complex trophic relationship between the dying larval epithelium and the new adult one, which is established during metamorphosis. This study, besides representing the first morphological and functional characterization of the changes that occur in the midgut of a lepidopteron during the transition from the larva to the moth, provides a detailed analysis of the midgut of the adult insect, a stage that has been neglected up to now.

Bryophyte-Feeders in a Basal Brachyceran Lineage (Diptera: Rhagionidae: Spaniinae): Adult Oviposition Behavior and Changes in the Larval Mouthpart Morphology Accompanied with the Diet Shifts

PubMed Central

Kato, Makoto

2016-01-01

Dipteran larval morphology exhibits overwhelming variety, affected by their diverse feeding habits and habitat use. In particular, larval mouthpart morphology is associated with feeding behavior, providing key taxonomic traits. Despite most larval Brachycera being carnivorous, a basal brachyceran family, Rhagionidae, contains bryophyte-feeding taxa with multiple feeding habits. To elucidate the life history, biology, and morphological evolution of the bryophyte-feeding rhagionids, the larval feeding behavior and morphology, and the adult oviposition behavior of four species belonging to three genera of Spaniinae (Spania Meigen, Litoleptis Chillcott and Ptiolina Zetterstedt) are described. Moreover, changes of the larval morphology associated with the evolution of bryophyte-feeding are traced by molecular phylogenetic analyses. Spania and Litoleptis (thallus-miners of thallose liverworts) share a toothed form of apical mandibular sclerite with an orifice on its dorsal surface, which contrasts to those of the other members of Rhagionidae possessing a blade-like mandibular hook with an adoral groove; whereas, Ptiolina (stem borer of mosses) exhibits a weak groove on the adoral surface of mandible and highly sclerotized maxilla with toothed projections. Based on the larval feeding behavior of the thallus-miners, it is inferred that the toothed mandibles with the dorsal orifice facilitate scraping plant tissue and then imbibing it with a great deal of the sap. A phylogeny indicated that the bryophyte-feeding genera formed a clade with Spaniopsis and was sister to Symphoromyia, which presumably are detritivores. This study indicates that the loss or reduction of adoral mandibular groove and mandibular brush is coincident with the evolution of bryophyte-feeding, and it is subsequently followed by the occurrence of dorsal mandibular orifice and the loss of creeping welts accompanying the evolution of thallus-mining. PMID:27812169

A method for high purity intestinal epithelial cell culture from adult human and murine tissues for the investigation of innate immune function.

PubMed

Graves, Christina L; Harden, Scott W; LaPato, Melissa; Nelson, Michael; Amador, Byron; Sorenson, Heather; Frazier, Charles J; Wallet, Shannon M

2014-12-01

Intestinal epithelial cells (IECs) serve as an important physiologic barrier between environmental antigens and the host intestinal immune system. Thus, IECs serve as a first line of defense and may act as sentinel cells during inflammatory insults. Despite recent renewed interest in IEC contributions to host immune function, the study of primary IEC has been hindered by lack of a robust culture technique, particularly for small intestinal and adult tissues. Here, a novel adaptation for culture of primary IEC is described for human duodenal organ donor tissue as well as duodenum and colon of adult mice. These epithelial cell cultures display characteristic phenotypes and are of high purity. In addition, the innate immune function of human primary IEC, specifically with regard to Toll-like receptor (TLR) expression and microbial ligand responsiveness, is contrasted with a commonly used intestinal epithelial cell line (HT-29). Specifically, TLR expression at the mRNA level and production of cytokine (IFNγ and TNFα) in response to TLR agonist stimulation is assessed. Differential expression of TLRs as well as innate immune responses to ligand stimulation is observed in human-derived cultures compared to that of HT-29. Thus, use of this adapted method to culture primary epithelial cells from adult human donors and from adult mice will allow for more appropriate studies of IECs as innate immune effectors. Published by Elsevier B.V.

Balancing crosstalk between 20-hydroxyecdysone-induced autophagy and caspase activity in the fat body during Drosophila larval-prepupal transition.

PubMed

Liu, Hanhan; Jia, Qiangqiang; Tettamanti, Gianluca; Li, Sheng

2013-11-01

In the fruitfly, Drosophila melanogaster, autophagy and caspase activity function in parallel in the salivary gland during metamorphosis and in a common regulatory hierarchy during oogenesis. Both autophagy and caspase activity progressively increase in the remodeling fat body, and they are induced by a pulse of the molting hormone (20-hydroxyecdysone, 20E) during the larval-prepupal transition. Inhibition of autophagy and/or caspase activity in the remodeling fat body results in 25-40% pupal lethality, depending on the genotypes. Interestingly, a balancing crosstalk occurs between autophagy and caspase activity in this tissue: the inhibition of autophagy induces caspase activity and the inhibition of caspases induces autophagy. The Drosophila remodeling fat body provides an in vivo model for understanding the molecular mechanism of the balancing crosstalk between autophagy and caspase activity, which oppose with each other and are induced by the common stimulus 20E, and blockage of either path reinforces the other path. Copyright © 2013 Elsevier Ltd. All rights reserved.

Patterning the dorsal longitudinal flight muscles (DLM) of Drosophila: insights from the ablation of larval scaffolds

NASA Technical Reports Server (NTRS)

Fernandes, J. J.; Keshishian, H.

1996-01-01

The six Dorsal Longitudinal flight Muscles (DLMs) of Drosophila develop from three larval muscles that persist into metamorphosis and serve as scaffolds for the formation of the adult fibers. We have examined the effect of muscle scaffold ablation on the development of DLMs during metamorphosis. Using markers that are specific to muscle and myoblasts we show that in response to the ablation, myoblasts which would normally fuse with the larval muscle, fuse with each other instead, to generate the adult fibers in the appropriate regions of the thorax. The development of these de novo DLMs is delayed and is reflected in the delayed expression of erect wing, a transcription factor thought to control differentiation events associated with myoblast fusion. The newly arising muscles express the appropriate adult-specific Actin isoform (88F), indicating that they have the correct muscle identity. However, there are frequent errors in the number of muscle fibers generated. Ablation of the larval scaffolds for the DLMs has revealed an underlying potential of the DLM myoblasts to initiate de novo myogenesis in a manner that resembles the mode of formation of the Dorso-Ventral Muscles, DVMs, which are the other group of indirect flight muscles. Therefore, it appears that the use of larval scaffolds is a superimposition on a commonly used mechanism of myogenesis in Drosophila. Our results show that the role of the persistent larval muscles in muscle patterning involves the partitioning of DLM myoblasts, and in doing so, they regulate formation of the correct number of DLM fibers.

The Drosophila TGF-beta/Activin-like ligands Dawdle and Myoglianin appear to modulate adult lifespan through regulation of 26S proteasome function in adult muscle

PubMed Central

Langerak, Shaughna; Kim, Myung-Jun; Lamberg, Hannah; Godinez, Michael; Main, Mackenzie; Winslow, Lindsey; O'Connor, Michael B.

2018-01-01

ABSTRACT The Drosophila Activin signaling pathway employs at least three separate ligands – Activin-β (Actβ), Dawdle (Daw), and Myoglianin (Myo) – to regulate several general aspects of fruit fly larval development, including cell proliferation, neuronal remodeling, and metabolism. Here we provide experimental evidence indicating that both Daw and Myo are anti-ageing factors in adult fruit flies. Knockdown of Myo or Daw in adult fruit flies reduced mean lifespan, while overexpression of either ligand in adult muscle tissues but not in adipose tissues enhanced mean lifespan. An examination of ubiquitinated protein aggregates in adult muscles revealed a strong inverse correlation between Myo- or Daw-initiated Activin signaling and the amount of ubiquitinated protein aggregates. We show that this correlation has important functional implications by demonstrating that the lifespan extension effect caused by overexpression of wild-type Daw or Myo in adult muscle tissues can be completely abrogated by knockdown of a 26S proteasome regulatory subunit Rpn1 in adult fly muscle, and that the prolonged lifespan caused by overexpression of Daw or Myo in adult muscle could be due to enhanced protein levels of the key subunits of 26S proteasome. Overall, our data suggest that Activin signaling initiated by Myo and Daw in adult Drosophila muscles influences lifespan, in part, by modulation of protein homeostasis through either direct or indirect regulation of the 26S proteasome levels. Since Myo is closely related to the vertebrate muscle mass regulator Myostatin (GDF8) and the Myostatin paralog GDF11, our observations may offer a new experimental model for probing the roles of GDF11/8 in ageing regulation in vertebrates. This article has an associated First Person interview with the first author of the paper. PMID:29615416

Temporal changes in the bacterial community of animal feces and their correlation with stable fly oviposition, larval development, and adult fitness

PubMed Central

Albuquerque, Thais A.; Zurek, Ludek

2014-01-01

Stable flies are blood-feeding insects with a great negative impact on animals world wide. Larvae develop primarily in animal manure and bacteria are essential for larval development; however, the principle of this dependence is not understood. We hypothesized that as the microbial community of animal manure changes over time, it plays an important role in stable fly fitness. Two-choice bioassays were conducted using 2 week old horse manure (control) and aging horse manure (fresh to 5 week old) to evaluate the effect of manure age on stable fly oviposition. Our data showed that fresh feces did not stimulate oviposition and that the attractiveness increased as manure aged but started to decline after 3 weeks. Bioassays assessing the effect of manure age at the time of oviposition on larval development demonstrated that 1–3 week old manure supported larval development significantly better than fresh, 4, and 5 week old manure. In addition, adult fitness (body size) was significantly higher in flies from 1 and 2 week old manure comparing to that of all other treatments. Analysis of the bacterial community of aging horse manure by 454-pyrosequencing of 16S rDNA revealed a great reduction in bacterial diversity and richness from fresh to 1–5 week old manure and a major shift from strict anaerobes in fresh manure to facultative anaerobes and strict aerobes in aged manure. Overall, the microbial community of 2 and 3 week old horse manure with its dominant bacterial taxa Rhizobium, Devosia, and Brevundimonas stimulated stable fly oviposition the most and provided a suitable habitat for larval development. These bacteria represent the candidates for studies focused on better understanding of stable fly – microbial interactions. PMID:25426108

Extracellular matrix remodeling and matrix metalloproteinases (ajMMP-2 like and ajMMP-16 like) characterization during intestine regeneration of sea cucumber Apostichopus japonicus.

PubMed

Miao, Ting; Wan, Zixuan; Sun, Lina; Li, Xiaoni; Xing, Lili; Bai, Yucen; Wang, Fang; Yang, Hongsheng

2017-10-01

Remodeling of extracellular matrix (ECM) regulated by matrix metalloproteinases (MMPs) is essential for tissue regeneration. In the present study, we used immunohistochemistry (IHC) techniques against ECM components to reveal changes of ECM during intestine regeneration of Apostichopus japonicus. The expression of collagen I and laminin reduced apparently from the eviscerated intestine, while fibronectin exhibited continuous expression in all regeneration stages observed. Meanwhile, we cloned two MMP genes from A. japonicus by RACE PCR. The full-length cDNA of ajMMP-2 like is 2733bp and contains a predicted open reading frame (ORF) of 1716bp encoding 572 amino acids. The full-length cDNA of ajMMP-16 like is 2705bp and contains an ORF of 1452bp encoding 484 amino acids. The predicted protein sequences of each MMP contain two conserved domains, ZnMc_MMP and HX. Homology and phylogenetic analysis revealed that ajMMP-2 like and ajMMP-16 like share high sequence similarity with MMP-2 and MMP-16 from Strongylocentrotus purpuratus, respectively. Then we investigated spatio-temporal expression of ajMMP-2 like and ajMMP-16 like during different regeneration stages by qRT-PCR and IHC. The expression pattern of them showed a roughly opposite trend from that of ECM components. According to our results, a fibronectin-dominate temporary matrix is created in intestine regeneration, and it might provide structural integrity for matrix and promote cell movement. We also hypothesize that ajMMP-2 like and ajMMP-16 like could accelerate cell migration and regulate interaction between ECM components and growth factors. This work provides new evidence of ECM and MMPs involvement in sea cucumber regeneration. Copyright © 2017 Elsevier Inc. All rights reserved.

Characterization of Intestinal Bacteria in Wild and Domesticated Adult Black Tiger Shrimp (Penaeus monodon)

PubMed Central

Rungrassamee, Wanilada; Klanchui, Amornpan; Maibunkaew, Sawarot; Chaiyapechara, Sage; Jiravanichpaisal, Pikul; Karoonuthaisiri, Nitsara

2014-01-01

The black tiger shrimp (Penaeus monodon) is a marine crustacean of economic importance in the world market. To ensure sustainability of the shrimp industry, production capacity and disease outbreak prevention must be improved. Understanding healthy microbial balance inside the shrimp intestine can provide an initial step toward better farming practice and probiotic applications. In this study, we employed a barcode pyrosequencing analysis of V3-4 regions of 16S rRNA genes to examine intestinal bacteria communities in wild-caught and domesticated P. monodon broodstock. Shrimp faeces were removed from intestines prior to further analysis in attempt to identify mucosal bacterial population. Five phyla, Actinobacteria, Fusobacteria, Proteobacteria, Firmicutes and Bacteroidetes, were found in all shrimp from both wild and domesticated environments. The operational taxonomic unit (OTU) was assigned at 97% sequence identity, and our pyrosequencing results identified 18 OTUs commonly found in both groups. Sequences of the shared OTUs were similar to bacteria in three phyla, namely i) Proteobacteria (Vibrio, Photobacterium, Novosphingobium, Pseudomonas, Sphingomonas and Undibacterium), ii) Firmicutes (Fusibacter), and iii) Bacteroidetes (Cloacibacterium). The shared bacterial members in P. monodon from two different habitats provide evidence that the internal environments within the host shrimp also exerts selective pressure on bacterial members. Intestinal bacterial profiles were compared using denaturing gradient gel electrophoresis (DGGE). The sequences from DGGE bands were similar to those of Vibrio and Photobacterium in all shrimp, consistent with pyrosequencing results. This work provides the first comprehensive report on bacterial populations in the intestine of adult black tiger shrimp and reveals some similar bacterial members between the intestine of wild-caught and domesticated shrimp. PMID:24618668

Larval leg integrity is maintained by Distal-less and is required for proper timing of metamorphosis in the flour beetle, Tribolium castaneum

PubMed Central

Suzuki, Yuichiro; Squires, Diego C.; Riddiford, Lynn M.

2009-01-01

The dramatic transformation from a larva to an adult must be accompanied by a coordinated activity of genes and hormones that enable an orchestrated transformation from larval to pupal/adult tissues. The maintenance of larval appendages and their subsequent transformation to appendages in holometabolous insects remains elusive at the developmental genetic level. Here the role of a key appendage patterning gene Distal-less (Dll) was examined in mid- to late- larval stages of the flour beetle, Tribolium castaneum. During late larval development, Dll was expressed in appendages in a similar manner as previously reported for the tobacco hornworm, Manduca sexta. Removal of this late Dll expression resulted in disruption of adult appendage patterning. Intriguingly, earlier removal resulted in dramatic loss of structural integrity and identity of larval appendages. A large amount of variability in appendage morphology was observed following Dll dsRNA injection, unlike larvae injected with dachshund dsRNA. These Dll dsRNA-injected larvae underwent numerous supernumerary molts, which could be terminated with injection of either JH methyltransferase or Methoprene-tolerant dsRNA. Apparently, the partial dedifferentiation of the appendages in these larvae acts to maintain high JH and, hence, prevents metamorphosis. PMID:19022238

Actin-interacting protein 1 controls assembly and permeability of intestinal epithelial apical junctions

PubMed Central

Baranwal, Somesh

2015-01-01

Adherens junctions (AJs) and tight junctions (TJs) are crucial regulators of the integrity and restitution of the intestinal epithelial barrier. The structure and function of epithelial junctions depend on their association with the cortical actin cytoskeleton that, in polarized epithelial cells, is represented by a prominent perijunctional actomyosin belt. The assembly and stability of the perijunctional cytoskeleton is controlled by constant turnover (disassembly and reassembly) of actin filaments. Actin-interacting protein (Aip) 1 is an emerging regulator of the actin cytoskeleton, playing a critical role in filament disassembly. In this study, we examined the roles of Aip1 in regulating the structure and remodeling of AJs and TJs in human intestinal epithelium. Aip1 was enriched at apical junctions in polarized human intestinal epithelial cells and normal mouse colonic mucosa. Knockdown of Aip1 by RNA interference increased the paracellular permeability of epithelial cell monolayers, decreased recruitment of AJ/TJ proteins to steady-state intercellular contacts, and attenuated junctional reassembly in a calcium-switch model. The observed defects of AJ/TJ structure and functions were accompanied by abnormal organization and dynamics of the perijunctional F-actin cytoskeleton. Moreover, loss of Aip1 impaired the apico-basal polarity of intestinal epithelial cell monolayers and inhibited formation of polarized epithelial cysts in 3-D Matrigel. Our findings demonstrate a previously unanticipated role of Aip1 in regulating the structure and remodeling of intestinal epithelial junctions and early steps of epithelial morphogenesis. PMID:25792565

Actin-interacting protein 1 controls assembly and permeability of intestinal epithelial apical junctions.

PubMed

Lechuga, Susana; Baranwal, Somesh; Ivanov, Andrei I

2015-05-01

Adherens junctions (AJs) and tight junctions (TJs) are crucial regulators of the integrity and restitution of the intestinal epithelial barrier. The structure and function of epithelial junctions depend on their association with the cortical actin cytoskeleton that, in polarized epithelial cells, is represented by a prominent perijunctional actomyosin belt. The assembly and stability of the perijunctional cytoskeleton is controlled by constant turnover (disassembly and reassembly) of actin filaments. Actin-interacting protein (Aip) 1 is an emerging regulator of the actin cytoskeleton, playing a critical role in filament disassembly. In this study, we examined the roles of Aip1 in regulating the structure and remodeling of AJs and TJs in human intestinal epithelium. Aip1 was enriched at apical junctions in polarized human intestinal epithelial cells and normal mouse colonic mucosa. Knockdown of Aip1 by RNA interference increased the paracellular permeability of epithelial cell monolayers, decreased recruitment of AJ/TJ proteins to steady-state intercellular contacts, and attenuated junctional reassembly in a calcium-switch model. The observed defects of AJ/TJ structure and functions were accompanied by abnormal organization and dynamics of the perijunctional F-actin cytoskeleton. Moreover, loss of Aip1 impaired the apico-basal polarity of intestinal epithelial cell monolayers and inhibited formation of polarized epithelial cysts in 3-D Matrigel. Our findings demonstrate a previously unanticipated role of Aip1 in regulating the structure and remodeling of intestinal epithelial junctions and early steps of epithelial morphogenesis. Copyright © 2015 the American Physiological Society.

The geometric framework for nutrition reveals interactions between protein and carbohydrate during larval growth in honey bees

USDA-ARS?s Scientific Manuscript database

In holometabolous insects, larval nutrition affects adult body size, a life history trait with a profound influence on performance and fitness. Individual nutritional components of larval diet are often complex and may interact with one another, necessitating the use of a geometric framework for und...

[Bone remodeling and modeling/mini-modeling.

PubMed

Hasegawa, Tomoka; Amizuka, Norio

Modeling, adapting structures to loading by changing bone size and shapes, often takes place in bone of the fetal and developmental stages, while bone remodeling-replacement of old bone into new bone-is predominant in the adult stage. Modeling can be divided into macro-modeling(macroscopic modeling)and mini-modeling(microscopic modeling). In the cellular process of mini-modeling, unlike bone remodeling, bone lining cells, i.e., resting flattened osteoblasts covering bone surfaces will become active form of osteoblasts, and then, deposit new bone onto the old bone without mediating osteoclastic bone resorption. Among the drugs for osteoporotic treatment, eldecalcitol(a vitamin D3 analog)and teriparatide(human PTH[1-34])could show mini-modeling based bone formation. Histologically, mature, active form of osteoblasts are localized on the new bone induced by mini-modeling, however, only a few cell layer of preosteoblasts are formed over the newly-formed bone, and accordingly, few osteoclasts are present in the region of mini-modeling. In this review, histological characteristics of bone remodeling and modeling including mini-modeling will be introduced.

Vinpocetine Attenuates Pathological Cardiac Remodeling by Inhibiting Cardiac Hypertrophy and Fibrosis.

PubMed

Wu, Mei-Ping; Zhang, Yi-Shuai; Xu, Xiangbin; Zhou, Qian; Li, Jian-Dong; Yan, Chen

2017-04-01

Pathological cardiac remodeling, characterized by cardiac hypertrophy and fibrosis, is a pathological feature of many cardiac disorders that leads to heart failure and cardiac arrest. Vinpocetine, a derivative of the alkaloid vincamine, has been used for enhancing cerebral blood flow to treat cognitive impairment. However, its role in pathological cardiac remodeling remains unknown. The aim of this study is to examine the effect of vinpocetine on pathological cardiac remodeling induced by chronic stimulation with angiotensin II (Ang II). Mice received Ang II infusion via osmotic pumps in the presence of vehicle or vinpocetine. Cardiac hypertrophy and fibrosis were assessed by morphological, histological, and biochemical analyses. Mechanistic studies were carried out in vitro with isolated mouse adult cardiac myocytes and fibroblasts. We showed that chronic Ang II infusion caused cardiac hypertrophy and fibrosis, which were all significantly attenuated by systemic administration of vinpocetine. In isolated adult mouse cardiomyocytes, vinpocetine suppressed Ang II-stimulated myocyte hypertrophic growth. In cultured cardiac fibroblasts, vinpocetine suppressed TGFβ-induced fibroblast activation and matrix gene expression, consistent with its effect in attenuating cardiac fibrosis. The effects of vinpocetine on cardiac myocyte hypertrophy and fibroblast activation are likely mediated by targeting cyclic nucleotide phosphodiesterase 1 (PDE1). Our results reveal a novel protective effect of vinpocetine in attenuating pathological cardiac remodeling through suppressing cardiac myocyte hypertrophic growth and fibroblast activation and fibrotic gene expression. These studies may also shed light on developing novel therapeutic agents for antagonizing pathological cardiac remodeling.

A-kinase anchoring proteins that regulate cardiac remodeling.

PubMed

Carnegie, Graeme K; Burmeister, Brian T

2011-11-01

In response to injury or stress, the adult heart undergoes maladaptive changes, collectively defined as pathological cardiac remodeling. Here, we focus on the role of A-kinase anchoring proteins (AKAPs) in 3 main areas associated with cardiac remodeling and the progression of heart failure: excitation-contraction coupling, sarcomeric regulation, and induction of pathological hypertrophy. AKAPs are a diverse family of scaffold proteins that form multiprotein complexes, integrating cAMP signaling with protein kinases, phosphatases, and other effector proteins. Many AKAPs have been characterized in the heart, where they play a critical role in modulating cardiac function.

A-Kinase Anchoring Proteins That Regulate Cardiac Remodeling

PubMed Central

Carnegie, Graeme K.; Burmeister, Brian T.

2012-01-01

In response to injury or stress, the adult heart undergoes maladaptive changes, collectively defined as pathological cardiac remodeling. Here, we focus on the role of A-kinase anchoring proteins (AKAPs) in 3 main areas associated with cardiac remodeling and the progression of heart failure: excitation–contraction coupling, sarcomeric regulation, and induction of pathological hypertrophy. AKAPs are a diverse family of scaffold proteins that form multi-protein complexes, integrating cAMP signaling with protein kinases, phosphatases, and other effector proteins. Many AKAPs have been characterized in the heart, where they play a critical role in modulating cardiac function. PMID:22075671

[BIO-INSECTICIDAL ACTIVITY OF ALPINIA GALANGA (L.) ON LARVAL DEVELOPMENT OF SPODOPTERA LITURA (LEPIDOPTERA: NOCTUIDAE).

PubMed

Pumchan, A; Puangsomchit, A; Temyarasilp, P; Pluempanupat, W; Bullangpoti, V

2015-01-01

The aim of the study was to assess the bio-efficacy of four Alpinia galanga rhizome crude extracts against the second and third instars of Spodoptera litura, an important field pest. The growth of younger larvae was significantly affected while that of the older larval stage was less influenced. In both stages, the methanol crude extract showed the greatest efficiency which caused the highest number of abnormal adults to occur and produced a large LD₅₀ value (12.816 µg/ larvae) pupicidal percentage after treatment, whereas, hexane extract caused the highest mortality during the larval-pupal stage after treatment with an LD₅₀ value of 6.354 µg/ larvae. However, the larval development was not significantly different among all treated larvae compared to the control. This study suggests that secondary larval instars of S. litura are more susceptible to the larval growth inhibitory action of Alpinia galanga extracts and these extracts could also be applied for use in the management of pests.

Occurrence of Terranova larval types (Nematoda: Anisakidae) in Australian marine fish with comments on their specific identities

PubMed Central

Suthar, Jaydipbhai

2016-01-01

Pseudoterranovosis is a well-known human disease caused by anisakid larvae belonging to the genus Pseudoterranova. Human infection occurs after consuming infected fish. Hence the presence of Pseudoterranova larvae in the flesh of the fish can cause serious losses and problems for the seafood, fishing and fisheries industries. The accurate identification of Pseudoterranova larvae in fish is important, but challenging because the larval stages of a number of different genera, including Pseudoterranova, Terranova and Pulchrascaris, look similar and cannot be differentiated from each other using morphological criteria, hence they are all referred to as Terranova larval type. Given that Terranova larval types in seafood are not necessarily Pseudoterranova and may not be dangerous, the aim of the present study was to investigate the occurrence of Terranova larval types in Australian marine fish and to determine their specific identity. A total of 137 fish belonging to 45 species were examined. Terranova larval types were found in 13 species, some of which were popular edible fish in Australia. The sequences of the first and second internal transcribed spacers (ITS-1 and ITS-2 respectively) of the Terranova larvae in the present study showed a high degree of similarity suggesting that they all belong to the same species. Due to the lack of a comparable sequence data of a well identified adult in the GenBank database the specific identity of Terranova larval type in the present study remains unknown. The sequence of the ITS regions of the Terranova larval type in the present study and those of Pseudoterranova spp. available in GenBank are significantly different, suggesting that larvae found in the present study do not belong to the genus Pseudoterranova, which is zoonotic. This study does not rule out the presence of Pseudoterranova larvae in Australian fish as Pseudoterranova decipiens E has been reported in adult form from seals in Antarctica and it is known that they

Suction feeding across fish life stages: flow dynamics from larvae to adults and implications for prey capture.

PubMed

Yaniv, Sarit; Elad, David; Holzman, Roi

2014-10-15

Suction feeding is thought to be the primary mode of prey capture in most larval fishes. Similar to adult suction feeders, larvae swim towards their prey while rapidly expanding their mouth cavity to generate an inward flow of water that draws the prey into the mouth. Although larvae are known to experience flows with lower Reynolds numbers than adults, it is unclear how the suction-induced flow field changes throughout ontogeny, and how such changes relate to prey capture performance. To address these questions, we determined mouth dimensions and opening speeds in Sparus aurata from first-feeding larvae to adults. We proceeded to develop a computational model of mouth expansion in order to analyze the scaling of suction flows under the observed parameters. Larval fish produced suction flows that were around two orders of magnitude slower than those of adults. Compared with adult fish, in which flow speed decays steeply with distance in front of the mouth, flow speed decayed more gradually in larval fish. This difference indicates that viscous forces in low Reynolds number flows modify the spatial distribution flow speed in front of the mouth. Consequently, simulated predator-prey encounters showed that larval fish could capture inert prey from a greater distance compared with adults. However, if prey attempted to escape then larval fish performed poorly: simulations inferred capture success in only weakly escaping prey immediately in front of the mouth. These ontogenetic changes in Reynolds number, suction-induced flow field and feeding performance could explain a widespread ontogenetic diet shift from passive prey at early life stages to evasive prey as larvae mature. © 2014. Published by The Company of Biologists Ltd.

Organization of the Drosophila larval visual circuit

PubMed Central

Gendre, Nanae; Neagu-Maier, G Larisa; Fetter, Richard D; Schneider-Mizell, Casey M; Truman, James W; Zlatic, Marta; Cardona, Albert

2017-01-01

Visual systems transduce, process and transmit light-dependent environmental cues. Computation of visual features depends on photoreceptor neuron types (PR) present, organization of the eye and wiring of the underlying neural circuit. Here, we describe the circuit architecture of the visual system of Drosophila larvae by mapping the synaptic wiring diagram and neurotransmitters. By contacting different targets, the two larval PR-subtypes create two converging pathways potentially underlying the computation of ambient light intensity and temporal light changes already within this first visual processing center. Locally processed visual information then signals via dedicated projection interneurons to higher brain areas including the lateral horn and mushroom body. The stratified structure of the larval optic neuropil (LON) suggests common organizational principles with the adult fly and vertebrate visual systems. The complete synaptic wiring diagram of the LON paves the way to understanding how circuits with reduced numerical complexity control wide ranges of behaviors.

Effects of beach morphology and waves on onshore larval transport

NASA Astrophysics Data System (ADS)

Fujimura, A.; Reniers, A.; Paris, C. B.; Shanks, A.; MacMahan, J.; Morgan, S.

2015-12-01

Larvae of intertidal species grow offshore, and migrate back to the shore when they are ready to settle on their adult substrates. In order to reach the habitat, they must cross the surf zone, which is characterized as a semi-permeable barrier. This is accomplished through physical forcing (i.e., waves and current) as well as their own behavior. Two possible scenarios of onshore larval transport are proposed: Negatively buoyant larvae stay in the bottom boundary layer because of turbulence-dependent sinking behavior, and are carried toward the shore by streaming of the bottom boundary layer; positively buoyant larvae move to the shore during onshore wind events, and sink to the bottom once they encounter high turbulence (i.e., surf zone edge), where they are carried by the bottom current toward the shore (Fujimura et al. 2014). Our biophysical Lagrangian particle tracking model helps to explain how beach morphology and wave conditions affect larval distribution patterns and abundance. Model results and field observations show that larval abundance in the surf zone is higher at mildly sloped, rip-channeled beaches than at steep pocket beaches. Beach attributes are broken up to examine which and how beach configuration factors affect larval abundance. Modeling with alongshore uniform beaches with variable slopes reveal that larval populations in the surf zone are negatively correlated with beach steepness. Alongshore variability enhances onshore larval transport because of increased cross-shore water exchange by rip currents. Wave groups produce transient rip currents and enhance cross-shore exchange. Effects of other wave components, such as wave height and breaking wave rollers are also considered.

General Information about Small Intestine Cancer

MedlinePlus

... Small Intestine Cancer Treatment (PDQ®)–Patient Version General Information About Small Intestine Cancer Go to Health Professional ... the PDQ Adult Treatment Editorial Board . Clinical Trial Information A clinical trial is a study to answer ...

A new clarification method to visualize biliary degeneration during liver metamorphosis in sea lamprey (Petromyzon marinus)

USGS Publications Warehouse

Chung-Davidson, Yu-Wen; Davidson, Peter J.; Scott, Anne M.; Walaszczyk, Erin J.; Brant, Cory O.; Buchinger, Tyler; Johnson, Nicholas S.; Li, Weiming

2014-01-01

Biliary atresia is a rare disease of infancy, with an estimated 1 in 15,000 frequency in the southeast United States, but more common in East Asian countries, with a reported frequency of 1 in 5,000 in Taiwan. Although much is known about the management of biliary atresia, its pathogenesis is still elusive. The sea lamprey (Petromyzon marinus) provides a unique opportunity to examine the mechanism and progression of biliary degeneration. Sea lamprey develop through three distinct life stages: larval, parasitic, and adult. During the transition from larvae to parasitic juvenile, sea lamprey undergo metamorphosis with dramatic reorganization and remodeling in external morphology and internal organs. In the liver, the entire biliary system is lost, including the gall bladder and the biliary tree. A newly-developed method called “CLARITY” was modified to clarify the entire liver and the junction with the intestine in metamorphic sea lamprey. The process of biliary degeneration was visualized and discerned during sea lamprey metamorphosis by using laser scanning confocal microscopy. This method provides a powerful tool to study biliary atresia in a unique animal model.

Toxicity of organophosphorus pesticide sumithion on larval stages of stinging catfish Heteropneustes fossilis

NASA Astrophysics Data System (ADS)

Shahjahan, Md.; Kabir, Md. Farajul; Sumon, Kizar Ahmed; Bhowmik, Lipi Rani; Rashid, Harunur

2017-01-01

Sumithion is widely used to control brittle in paddy fields and tiger bug in fish larval rearing ponds. The objective of this study was to elucidate the toxic effects of sumithion on larval stages of stinging catfish Heteropneustes fossilis. Larvae were exposed to two concentrations (150 and 250 μg/L) of sumithion with one control in three replicates of each. Larvae samples were collected at 20- and 24-h intervals followed by observation under a digital microscope. Exposures of stinging catfish larvae to sumithion produced deformities including irregular head shape, lordosis, yolk sac edema, body arcuation, tissue ulceration, etc. The mortality rates of larvae were significantly increased in response to increase in sumithion concentrations. Furthermore, around 30% of the total adult stinging catfish reared in sumithiontreated aquaculture ponds were found to be deformed permanently. These findings highlight that exposure of stinging catfish to sumithion at the critical and sensitive stages in their life cycle may significantly reduce the number of returning adults. Therefore, the use of sumithion for crop protection needs to be considered carefully and alternatives to sumithion should to be developed for controlling aquatic insects in aqua-ponds during larval rearing.

Soundscapes and Larval Settlement: Characterizing the Stimulus from a Larval Perspective.

PubMed

Lillis, Ashlee; Eggleston, David B; Bohnenstiehl, DelWayne R

2016-01-01

There is growing evidence that underwater sounds serve as a cue for the larvae of marine organisms to locate suitable settlement habitats; however, the relevant spatiotemporal scales of variability in habitat-related sounds and how this variation scales with larval settlement processes remain largely uncharacterized, particularly in estuarine habitats. Here, we provide an overview of the approaches we have developed to characterize an estuarine soundscape as it relates to larval processes, and a conceptual framework is provided for how habitat-related sounds may influence larval settlement, using oyster reef soundscapes as an example.

Reef-fish larval dispersal patterns validate no-take marine reserve network connectivity that links human communities

NASA Astrophysics Data System (ADS)

Abesamis, Rene A.; Saenz-Agudelo, Pablo; Berumen, Michael L.; Bode, Michael; Jadloc, Claro Renato L.; Solera, Leilani A.; Villanoy, Cesar L.; Bernardo, Lawrence Patrick C.; Alcala, Angel C.; Russ, Garry R.

2017-09-01

Networks of no-take marine reserves (NTMRs) are a widely advocated strategy for managing coral reefs. However, uncertainty about the strength of population connectivity between individual reefs and NTMRs through larval dispersal remains a major obstacle to effective network design. In this study, larval dispersal among NTMRs and fishing grounds in the Philippines was inferred by conducting genetic parentage analysis on a coral-reef fish ( Chaetodon vagabundus). Adult and juvenile fish were sampled intensively in an area encompassing approximately 90 km of coastline. Thirty-seven true parent-offspring pairs were accepted after screening 1978 juveniles against 1387 adults. The data showed all types of dispersal connections that may occur in NTMR networks, with assignments suggesting connectivity among NTMRs and fishing grounds ( n = 35) far outnumbering those indicating self-recruitment ( n = 2). Critically, half (51%) of the inferred occurrences of larval dispersal linked reefs managed by separate, independent municipalities and constituent villages, emphasising the need for nested collaborative management arrangements across management units to sustain NTMR networks. Larval dispersal appeared to be influenced by wind-driven seasonal reversals in the direction of surface currents. The best-fit larval dispersal kernel estimated from the parentage data predicted that 50% of larvae originating from a population would attempt to settle within 33 km, and 95% within 83 km. Mean larval dispersal distance was estimated to be 36.5 km. These results suggest that creating a network of closely spaced (less than a few tens of km apart) NTMRs can enhance recruitment for protected and fished populations throughout the NTMR network. The findings underscore major challenges for regional coral-reef management initiatives that must be addressed with priority: (1) strengthening management of NTMR networks across political or customary boundaries; and (2) achieving adequate population

Expression of an intestine-specific transcription factor (CDX1) in intestinal metaplasia and in subsequently developed intestinal type of cholangiocarcinoma in rat liver.

PubMed

Ren, P; Silberg, D G; Sirica, A E

2000-02-01

CDX1 is a caudal-type homeobox intestine-specific transcription factor that has been shown to be selectively expressed in epithelial cells in intestinal metaplasia of the human stomach and esophagus and variably expressed in human gastric and esophageal adenocarcinomas (Silberg DG, Furth EE, Taylor JK, Schuck T, Chiou T, Traber PG: Gastroenterology 1997, 113: 478-486). Through the use of immunohistochemistry and Western blotting, we investigated whether CDX1 is also uniquely associated with the intestinal metaplasia associated with putative precancerous cholangiofibrosis induced in rat liver during furan cholangiocarcinogenesis, as well as expressed in neoplastic glands in a subsequently developed intestinal type of cholangiocarcinoma. In normal, control adult rat small intestine, specific nuclear immunoreactivity for CDX1 was most prominent in enterocytes lining the crypts. In comparison, epithelium from intestinal metaplastic glands within furan-induced hepatic cholangiofibrosis and neoplastic epithelium from later developed primary intestinal-type cholangiocarcinoma each demonstrated strong nuclear immunoreactivity for CDX1. CDX1-positive cells were detected in hepatic cholangiofibrotic tissue as early as 3 weeks after the start of chronic furan treatment. We further determined that the percentages of CDX1-positive neoplastic glands and glandular nuclei are significantly higher in primary tumors than in a derived, transplantable cholangiocarcinoma serially-propagated in vivo. Western blotting confirmed our immunohistochemical results, and no CDX1 immunoreactivity was detected in normal adult rat liver or in hyperplastic biliary epithelial cells. These findings indicate that CDX1 is specifically associated with early intestinal metaplasia and a later developed intestinal-type of cholangiocarcinoma induced in the liver of furan-treated rats.

Lymphatic dysregulation in intestinal inflammation: new insights into inflammatory bowel disease pathomechanisms.

PubMed

Becker, F; Yi, P; Al-Kofahi, M; Ganta, V C; Morris, J; Alexander, J S

2014-03-01

Alterations in the intestinal lymphatic network are well-established features of human and experimental inflammatory bowel disease (IBD). Such lymphangiogenic expansion might enhance classic intestinal lymphatic transport, eliminating excess accumulations of fluid, inflammatory cells and mediators, and could therefore be interpreted as an 'adaptive' response to acute and chronic inflammatory processes. However, whether these new lymphatic vessels are functional, unregulated or immature (and what factors may promote 'maturation' of these vessels) is currently an area under intense investigation. It is still controversial whether impaired lymphatic function in IBD is a direct consequence of the intestinal inflammation, or a preceding lymphangitis-like event. Current research has uncovered novel regulatory factors as well as new roles for familiar signaling pathways, which appear to be linked to inflammation-induced lymphatic alterations. The current review summarizes mechanisms amplifying lymphatic dysregulation and remodeling in intestinal inflammation at the organ, cell and molecular levels and discusses the influence of lymphangiogenesis and intestinal lymphatic transport function as they relate to IBD pathophysiology.

The chromatin remodeler chd5 is necessary for proper head development during embryogenesis of Danio rerio.

PubMed

Bishop, Brett; Ho, Kwok Ki; Tyler, Kim; Smith, Amanda; Bonilla, Sylvia; Leung, Yuk Fai; Ogas, Joe

2015-08-01

The chromatin remodeler CHD5 plays a critical role in tumor suppression and neurogenesis in mammals. CHD5 contributes to gene expression during neurogenesis, but there is still much to learn regarding how this class of remodelers contributes to differentiation and development. CHD5 remodelers are vertebrate-specific, raising the prospect that CHD5 plays one or more conserved roles in this phylum. Expression of chd5 in adult fish closely mirrors expression of CHD5 in adult mammals. Knockdown of Chd5 during embryogenesis suggests new roles for CHD5 remodelers based on resulting defects in craniofacial development including reduced head and eye size as well as reduced cartilage formation in the head. In addition, knockdown of Chd5 results in altered expression of neural markers in the developing brain and eye as well as a profound defect in differentiation of dopaminergic amacrine cells. Recombinant zebrafish Chd5 protein exhibits nucleosome remodeling activity in vitro, suggesting that it is the loss of this activity that contributes to the observed phenotypes. Our studies indicate that zebrafish is an appropriate model for functional characterization of CHD5 remodelers in vertebrates and highlight the potential of this model for generating novel insights into the role of this vital class of remodelers. Copyright © 2015. Published by Elsevier B.V.

A review of postfeeding larval dispersal in blowflies: implications for forensic entomology

NASA Astrophysics Data System (ADS)

Gomes, Leonardo; Godoy, Wesley Augusto Conde; von Zuben, Claudio José

2006-05-01

Immature and adult stages of blowflies are one of the primary invertebrate consumers of decomposing animal organic matter. When the food supply is consumed or when the larvae complete their development and migrate prior to the total removal of the larval substrate, they disperse to find adequate places for pupation, a process known as postfeeding larval dispersal. Several important ecological and physiological aspects of this process were studied since the work by Green (Ann Appl Biol 38:475, 1951) 50 years ago. An understanding of postfeeding larval dispersal can be useful for determining the postmortem interval (PMI) of human cadavers in legal medicine, particularly because this interval may be underestimated if older dispersing larvae or those that disperse longer, faster, and deeper are not taken into account. In this article, we review the process of postfeeding larval dispersal and its implications for legal medicine, in particular showing that aspects such as burial behavior and competition among species of blowflies can influence this process and consequently, the estimation of PMI.

Invasion of intestinal epithelia in vitro by the parasitic nematode Trichinella spiralis.

PubMed Central

ManWarren, T; Gagliardo, L; Geyer, J; McVay, C; Pearce-Kelling, S; Appleton, J

1997-01-01

Studies of nematode establishment in intestinal niches has been hindered by the lack of a readily manipulated in vitro assay. In this report, experiments are described wherein the larval stage of the parasitic nematode Trichinella spiralis was shown to invade epithelial cell monolayers in vitro. Larvae penetrated cells and migrated through them, leaving trails of dead cells in their wake. Cells derived from five different species were susceptible to invasion, reflecting the broad host range of T. spiralis in vivo. Epithelial cells derived from large and small intestines and kidneys were susceptible. Fibroblast and muscle cells were resistant. Larvae deposited glycoprotein antigens in the cells they invaded. Although the function of these antigens is unknown, they are targeted by rat antibodies that cause T. spiralis to be expelled from the intestine. The model system described provides the means to further investigate this process as well as the mechanisms by which this parasitic nematode establishes its intestinal niche. PMID:9353069

Neurodevelopmental Low-dose Bisphenol A Exposure Leads to Early Life-stage Hyperactivity and Learning Deficits in Adult Zebrafish

PubMed Central

Saili, Katerine S.; Corvi, Margaret M.; Weber, Daniel N.; Patel, Ami U.; Das, Siba R.; Przybyla, Jennifer; Anderson, Kim A.; Tanguay, Robert L.

2011-01-01

Developmental bisphenol A (BPA) exposure has been implicated in adverse behavior and learning deficits. The mode of action underlying these effects is unclear. The zebrafish model was employed to investigate the neurobehavioral effects of developmental bisphenol A (BPA) exposure. The objectives of this study were to identify whether low-dose, developmental BPA exposure affects larval zebrafish locomotor behavior and whether learning deficits occur in adults exposed during development. Two control compounds, 17β-estradiol (an estrogen receptor ligand) and GSK4716 (a synthetic estrogen related receptor gamma ligand), were included. Larval toxicity assays were used to determine appropriate BPA, 17β-estradiol, and GSK4716 concentrations for behavior testing. BPA tissue uptake was analyzed using HPLC and lower doses were extrapolated using a linear regression analysis. Larval behavior tests were conducted using a ViewPoint Zebrabox. Adult learning tests were conducted using a custom-built T-maze. BPA exposure to ≤30 μM was nonteratogenic in zebrafish. Neurodevelopmental BPA exposure to 0.01, 0.1, or 1 μM led to larval hyperactivity or learning deficits in adult zebrafish. Exposure to 0.1 μM 17β-estradiol or GSK4716 also led to larval hyperactivity. This study demonstrates the efficacy of using the larval zebrafish model for studying the neurobehavioral effects of low-dose developmental BPA exposure. PMID:22108044

Vinpocetine Attenuates Pathological Cardiac Remodeling by Inhibiting Cardiac Hypertrophy and Fibrosis

PubMed Central

Wu, Mei-ping; Zhang, Yi-shuai; Xu, Xiangbin; Zhou, Qian

2017-01-01

Purpose Pathological cardiac remodeling, characterized by cardiac hypertrophy and fibrosis, is a pathological feature of many cardiac disorders that leads to heart failure and cardiac arrest. Vinpocetine, a derivative of the alkaloid vincamine, has been used for enhancing cerebral blood flow to treat cognitive impairment. However, its role in pathological cardiac remodeling remains unknown. The aim of this study is to examine the effect of vinpocetine on pathological cardiac remodeling induced by chronic stimulation with angiotensin II (Ang II). Methods Mice received Ang II infusion via osmotic pumps in the presence of vehicle or vinpocetine. Cardiac hypertrophy and fibrosis were assessed by morphological, histological, and biochemical analyses. Mechanistic studies were carried out in vitro with isolated mouse adult cardiac myocytes and fibroblasts. Results We showed that chronic Ang II infusion caused cardiac hypertrophy and fibrosis, which were all significantly attenuated by systemic administration of vinpocetine. In isolated adult mouse cardiomyocytes, vinpocetine suppressed Ang II-stimulated myocyte hypertrophic growth. In cultured cardiac fibroblasts, vinpocetine suppressed TGFβ-induced fibroblast activation and matrix gene expression, consistent with its effect in attenuating cardiac fibrosis. The effects of vinpocetine on cardiac myocyte hypertrophy and fibroblast activation are likely mediated by targeting cyclic nucleotide phosphodiesterase 1 (PDE1). Conclusions Our results reveal a novel protective effect of vinpocetine in attenuating pathological cardiac remodeling through suppressing cardiac myocyte hypertrophic growth and fibroblast activation and fibrotic gene expression. These studies may also shed light on developing novel therapeutic agents for antagonizing pathological cardiac remodeling. PMID:28321644

Postembryonic lineages of the Drosophila ventral nervous system: Neuroglian expression reveals the adult hemilineage associated fiber tracts in the adult thoracic neuromeres.

PubMed

Shepherd, David; Harris, Robin; Williams, Darren W; Truman, James W

2016-09-01

During larval life most of the thoracic neuroblasts (NBs) in Drosophila undergo a second phase of neurogenesis to generate adult-specific neurons that remain in an immature, developmentally stalled state until pupation. Using a combination of MARCM and immunostaining with a neurotactin antibody, Truman et al. (2004; Development 131:5167-5184) identified 24 adult-specific NB lineages within each thoracic hemineuromere of the larval ventral nervous system (VNS), but because of the neurotactin labeling of lineage tracts disappearing early in metamorphosis, they were unable extend the identification of these lineages into the adult. Here we show that immunostaining with an antibody against the cell adhesion molecule neuroglian reveals the same larval secondary lineage projections through metamorphosis and bfy identifying each neuroglian-positive tract at selected stages we have traced the larval hemilineage tracts for all three thoracic neuromeres through metamorphosis into the adult. To validate tract identifications we used the genetic toolkit developed by Harris et al. (2015; Elife 4) to preserve hemilineage-specific GAL4 expression patterns from larval into the adult stage. The immortalized expression proved a powerful confirmation of the analysis of the neuroglian scaffold. This work has enabled us to directly link the secondary, larval NB lineages to their adult counterparts. The data provide an anatomical framework that 1) makes it possible to assign most neurons to their parent lineage and 2) allows more precise definitions of the neuronal organization of the adult VNS based in developmental units/rules. J. Comp. Neurol. 524:2677-2695, 2016. © 2016 The Authors The Journal of Comparative Neurology Published by Wiley Periodicals, Inc. © 2016 The Authors The Journal of Comparative Neurology Published by Wiley Periodicals, Inc.

Prevalence and Predictors of Intestinal Helminth Infections Among Human Immunodeficiency Virus Type 1–Infected Adults in an Urban African Setting

PubMed Central

Modjarrad, Kayvon; Zulu, Isaac; Redden, David T.; Njobvu, Lungowe; Freedman, David O.; Vermund, Sten H.

2009-01-01

Sub-Saharan Africa is disproportionately burdened by intestinal helminth and human immunodeficiency virus (HIV)-1 infection. Recent evidence suggests detrimental immunologic effects from concomitant infection with the two pathogens. Few studies, however, have assessed the prevalence of and predictors for intestinal helminth infection among HIV-1–infected adults in urban African settings where HIV infection rates are highest. We collected and analyzed sociodemographic and parasitologic data from 297 HIV-1–infected adults (mean age = 31.1 years, 69% female) living in Lusaka, Zambia to assess the prevalence and associated predictors of helminth infection. We found at least one type of intestinal helminth in 24.9% of HIV-infected adults. Thirty-nine (52.7%) were infected with Ascaris lumbricoides, and 29 (39.2%) were infected with hookworm. More than 80% were light-intensity infections. A recent visit to a rural area, food shortage, and prior history of helminth infection were significant predictors of current helminth status. The high helminth prevalence and potential for adverse interactions between helminths and HIV suggests that helminth diagnosis and treatment should be part of routine HIV care. PMID:16222025

Binary Cell Fate Decisions and Fate Transformation in the Drosophila Larval Eye

PubMed Central

Rister, Jens; Ng, June; Celik, Arzu; Sprecher, Simon G.

2013-01-01

The functionality of sensory neurons is defined by the expression of specific sensory receptor genes. During the development of the Drosophila larval eye, photoreceptor neurons (PRs) make a binary choice to express either the blue-sensitive Rhodopsin 5 (Rh5) or the green-sensitive Rhodopsin 6 (Rh6). Later during metamorphosis, ecdysone signaling induces a cell fate and sensory receptor switch: Rh5-PRs are re-programmed to express Rh6 and become the eyelet, a small group of extraretinal PRs involved in circadian entrainment. However, the genetic and molecular mechanisms of how the binary cell fate decisions are made and switched remain poorly understood. We show that interplay of two transcription factors Senseless (Sens) and Hazy control cell fate decisions, terminal differentiation of the larval eye and its transformation into eyelet. During initial differentiation, a pulse of Sens expression in primary precursors regulates their differentiation into Rh5-PRs and repression of an alternative Rh6-cell fate. Later, during the transformation of the larval eye into the adult eyelet, Sens serves as an anti-apoptotic factor in Rh5-PRs, which helps in promoting survival of Rh5-PRs during metamorphosis and is subsequently required for Rh6 expression. Comparably, during PR differentiation Hazy functions in initiation and maintenance of rhodopsin expression. Hazy represses Sens specifically in the Rh6-PRs, allowing them to die during metamorphosis. Our findings show that the same transcription factors regulate diverse aspects of larval and adult PR development at different stages and in a context-dependent manner. PMID:24385925

Binary cell fate decisions and fate transformation in the Drosophila larval eye.

PubMed

Mishra, Abhishek Kumar; Tsachaki, Maria; Rister, Jens; Ng, June; Celik, Arzu; Sprecher, Simon G

2013-01-01

The functionality of sensory neurons is defined by the expression of specific sensory receptor genes. During the development of the Drosophila larval eye, photoreceptor neurons (PRs) make a binary choice to express either the blue-sensitive Rhodopsin 5 (Rh5) or the green-sensitive Rhodopsin 6 (Rh6). Later during metamorphosis, ecdysone signaling induces a cell fate and sensory receptor switch: Rh5-PRs are re-programmed to express Rh6 and become the eyelet, a small group of extraretinal PRs involved in circadian entrainment. However, the genetic and molecular mechanisms of how the binary cell fate decisions are made and switched remain poorly understood. We show that interplay of two transcription factors Senseless (Sens) and Hazy control cell fate decisions, terminal differentiation of the larval eye and its transformation into eyelet. During initial differentiation, a pulse of Sens expression in primary precursors regulates their differentiation into Rh5-PRs and repression of an alternative Rh6-cell fate. Later, during the transformation of the larval eye into the adult eyelet, Sens serves as an anti-apoptotic factor in Rh5-PRs, which helps in promoting survival of Rh5-PRs during metamorphosis and is subsequently required for Rh6 expression. Comparably, during PR differentiation Hazy functions in initiation and maintenance of rhodopsin expression. Hazy represses Sens specifically in the Rh6-PRs, allowing them to die during metamorphosis. Our findings show that the same transcription factors regulate diverse aspects of larval and adult PR development at different stages and in a context-dependent manner.

Anopheline larval habitats seasonality and species distribution: a prerequisite for effective targeted larval habitats control programmes.

PubMed

Kweka, Eliningaya J; Zhou, Guofa; Munga, Stephen; Lee, Ming-Chieh; Atieli, Harrysone E; Nyindo, Mramba; Githeko, Andrew K; Yan, Guiyun

2012-01-01

Larval control is of paramount importance in the reduction of malaria vector abundance and subsequent disease transmission reduction. Understanding larval habitat succession and its ecology in different land use managements and cropping systems can give an insight for effective larval source management practices. This study investigated larval habitat succession and ecological parameters which influence larval abundance in malaria epidemic prone areas of western Kenya. A total of 51 aquatic habitats positive for anopheline larvae were surveyed and visited once a week for a period of 85 weeks in succession. Habitats were selected and identified. Mosquito larval species, physico-chemical parameters, habitat size, grass cover, crop cycle and distance to nearest house were recorded. Polymerase chain reaction revealed that An. gambiae s.l was the most dominant vector species comprised of An.gambiae s.s (77.60%) and An.arabiensis (18.34%), the remaining 4.06% had no amplification by polymerase chain reaction. Physico-chemical parameters and habitat size significantly influenced abundance of An. gambiae s.s (P = 0.024) and An. arabiensis (P = 0.002) larvae. Further, larval species abundance was influenced by crop cycle (P≤0.001), grass cover (P≤0.001), while distance to nearest houses significantly influenced the abundance of mosquito species larvae (r = 0.920;P≤0.001). The number of predator species influenced mosquito larval abundance in different habitat types. Crop weeding significantly influenced with the abundance of An.gambiae s.l (P≤0.001) when preceded with fertilizer application. Significantly higher anopheline larval abundance was recorded in habitats in pasture compared to farmland (P = 0.002). When habitat stability and habitat types were considered, hoof print were the most productive followed by disused goldmines. These findings suggest that implementation of effective larval control programme should be targeted with larval habitats

Septic tanks as larval habitats for the mosquitoes Aedes aegypti and Culex quinquefasciatus in Playa-Playita, Puerto Rico.

PubMed

Burke, R; Barrera, R; Lewis, M; Kluchinsky, T; Claborn, D

2010-06-01

Adult Aedes aegypti (Linnaeus) (Diptera: Culicidae) were previously recovered from emergence traps on septic tanks in southeastern Puerto Rico. In this study we quantified immature mosquito abundance and its relationship with structural variables of the septic tanks and chemical properties of the water containing raw sewage. A miniaturized floating funnel trap was used to sample 89 septic tanks for larvae in the Puerto Rican community of Playa-Playita. Aedes aegypti larvae were recovered from 18% of the sampled tanks (10.3 larvae per septic tank per day). Larval presence was positively associated with cracking of the septic tank walls and uncovered access ports. Larval abundance was positively associated with cracking of the septic tank walls and larger tank surface areas, and inversely associated with the total dissolved solids (TDS). Culex quinquefasciatus (Say) larvae were also recovered from 74% of the septic tanks (129.6 larvae per septic tank per day). Larval presence was negatively associated with TDS in the water and larval abundance was positively associated with cracking of the septic tank walls. A screened, plastic emergence trap was used to sample 93 septic tanks within the community for Ae. aegypti and Cx. quinquefasciatus adults. Aedes aegypti adults were recovered from 49% of the sampled tanks (8.7 adults per septic tank per day) and Cx. quinquefasciatus adults were recovered from 97% of the sampled tanks (155.5 adults per septic tank per day). Aedes aegypti adult presence was positively associated with cracking, uncapped openings and septic water pH. The Ae. aegypti adult counts were positively associated with cracking and inversely associated with TDS and conductivity. This study marks the first published record of the recovery of Ae. aegypti larvae from holding tanks containing raw sewage in the Caribbean region. Our study indicates that Ae. aegypti larvae are present in sewage water and that septic tanks have at least the potential to maintain

Different tocopherol isoforms vary in capacity to scavenge free radicals, prevent inflammatory response, and induce apoptosis in both adult- and fetal-derived intestinal epithelial cells.

PubMed

Elisia, Ingrid; Kitts, David D

2013-01-01

Gamma-tocopherol (γ-Toc) and δ-Toc are two vitamin E isoforms for which biological activities are not well established, yet these isoforms are present in many different sources of vegetable oils and, therefore, contribute significantly to the total dietary intake of vitamin E. Infant formula also contains relatively high amounts of γ-Toc and δ-Toc, compared with that found in human milk. The efficacy of γ-Toc and δ-Toc to modulate cellular events that include oxidative stress, inflammatory response, and apoptosis-mediated cytotoxicity, relative to α-Toc, was determined using differentiated Caco-2 and primary FHs 74 Int cells intestinal epithelial cell lines. Antioxidant capacity of Toc-isoforms followed the order of δ-Toc > γ-Toc > α-Toc against peroxyl radical-induced membrane oxidation in both Caco-2 and FHs 74 Int cells, respectively. The different Toc-isoforms suppressed inflammatory response in interferon (IFN) γ/phorbol myristate acetate (PMA)-induced Caco-2 adult-derived intestinal epithelial cells, but exacerbated both IL8 and PGE2 secretion in fetal-derived FHs 74 Int intestinal epithelial cells. Lastly, Toc exhibited an isoform-dependent apoptosis-mediated cytotoxicity, whereby δ-Toc elicited the greatest apoptosis followed by γ-Toc, whereas α-Toc was not cytotoxic. Cellular uptake of non-α-Toc isoforms were greater (P < 0.05) than that observed for α-Toc in both intestinal epithelial cell lines which in part explains the superior bioactive function observed for both γ-Toc and δ-Toc, compared with α-Toc. We conclude that the non-α-Toc isoforms of vitamin E have distinct roles that influence oxidative stress and inflammatory responses in both adult and fetal-derived intestinal epithelial cell lines. © 2013 International Union of Biochemistry and Molecular Biology.

Effects of chlorpyrifos on in vitro sex steroid production and thyroid follicular development in adult and larval Lake Sturgeon, Acipenser fulvescens.

PubMed

Brandt, Catherine; Burnett, Duncan C; Arcinas, Liane; Palace, Vince; Gary Anderson, W

2015-08-01

Chlorpyrifos is a widely used organophosphate pesticide that has previously been shown to enter waterways in biologically relevant concentrations and has the potential to disrupt both thyroid hormone and sex steroid biosynthesis in vertebrates. Because gonadal maturation and larval development in Lake Sturgeon, Acipenser fulvescens, potentially coincide with the application of chlorpyrifos we examined the effects of chlorpyrifos on both thyroid follicular development in larval Lake Sturgeon, and sex hormone synthesis in adult Lake Sturgeon. For the first time, the present study reports steroidogenesis from testicular and ovarian tissue in Lake Sturgeon using an established in vitro bioassay. Furthermore, incubating gonad tissue with 5, 500 or 2000ngmL(-1) chlorpyrifos revealed an inhibitory effect on testosterone synthesis in both testicular (control, 40.29pgmg(-1) tissue wet weight(-1)h(-1) compared to experimental, 21.84pgmg(-1) tissue wet weight(-1)h(-1)) and ovarian (control, 33.83pgmg(-1) tissue wet weight(-1)h(-1) compared to experimental, 15.19pgmg(-1) tissue wet weight(-1)h(-1)) tissue. In a second series of experiments, larval Lake Sturgeon were exposed to equivalent concentrations of chlorpyrifos as above for 10days (d) between hatch and the onset of exogenous feeding. Larvae from each treatment group were raised until 67days post hatch (dph) and growth rates were compared alongside key indicators of thyroid follicle growth. Chlorpyrifos treatment had no effect on the measured indicators of thyroid follicular development. Copyright © 2015 Elsevier Ltd. All rights reserved.

Burrowing activities of the larval lamprey

USGS Publications Warehouse

Sawyer, Philip J.

1959-01-01

Since the appearance in 1950 of Applegate's work on the sea lamprey in Michigan (U. S. Fish and Wildl. Serv., Spec. Sci. Rept.; Fish, No. 55) and the subsequent development of means to control lampreys in the Great Lakes, biologists have accumulated much additional information on adult lampreys. Larval lampreys, however, are difficult animals to observe in the field, and many facets of their behavior are still unknown. While working with the U. S. Fish and Wildlife Service, I kept ammocetes in captivity, and was able to observe their burrowing activities.

Cardiac Remodeling: Endothelial Cells Have More to Say Than Just NO

PubMed Central

Segers, Vincent F. M.; Brutsaert, Dirk L.; De Keulenaer, Gilles W.

2018-01-01

The heart is a highly structured organ consisting of different cell types, including myocytes, endothelial cells, fibroblasts, stem cells, and inflammatory cells. This pluricellularity provides the opportunity of intercellular communication within the organ, with subsequent optimization of its function. Intercellular cross-talk is indispensable during cardiac development, but also plays a substantial modulatory role in the normal and failing heart of adults. More specifically, factors secreted by cardiac microvascular endothelial cells modulate cardiac performance and either positively or negatively affect cardiac remodeling. The role of endothelium-derived small molecules and peptides—for instance NO or endothelin-1—has been extensively studied and is relatively well defined. However, endothelial cells also secrete numerous larger proteins. Information on the role of these proteins in the heart is scattered throughout the literature. In this review, we will link specific proteins that modulate cardiac contractility or cardiac remodeling to their expression by cardiac microvascular endothelial cells. The following proteins will be discussed: IL-6, periostin, tenascin-C, thrombospondin, follistatin-like 1, frizzled-related protein 3, IGF-1, CTGF, dickkopf-3, BMP-2 and−4, apelin, IL-1β, placental growth factor, LIF, WISP-1, midkine, and adrenomedullin. In the future, it is likely that some of these proteins can serve as markers of cardiac remodeling and that the concept of endothelial function and dysfunction might have to be redefined as we learn more about other factors secreted by ECs besides NO. PMID:29695980

Larval Diet Affects Male Pheromone Blend in a Laboratory Strain of the Medfly, Ceratitis capitata (Diptera: Tephritidae).

PubMed

Merli, Daniele; Mannucci, Barbara; Bassetti, Federico; Corana, Federica; Falchetto, Marco; Malacrida, Anna R; Gasperi, Giuliano; Scolari, Francesca

2018-04-01

The Mediterranean fruit fly (medfly) Ceratitis capitata is a polyphagous pest of fruits and crops with a worldwide distribution. Its ability to use different larval hosts may have multiple effects, including impacts on adult reproductive biology. The male sex pheromone, which plays a key role in attracting both other males to lekking arenas and females for mating, is a mixture of chemical compounds including esters, acids, alkanes and terpenes known to differ between laboratory strains and wild-type populations. The relationship between larval diet and adult pheromone composition remains unexplored. Here, we investigated the effect of larval diet, including laboratory media and fresh fruits, on the composition of the male pheromone mixture. Using Headspace Solid Phase Microextraction we collected the pheromone emitted by males reared as larvae on different substrates and found both qualitative and quantitative differences. A number of alkanes appeared to be typical of the pheromone of males reared on wheat bran-based larval medium, and these may be cuticular hydrocarbons involved in chemical communication. We also detected differences in pheromone composition related to adult male age, suggesting that variations in hormonal levels and/or adult diet could also play a role in determining the chemical profile emitted. Our findings highlight the plasticity of dietary responses of C. capitata, which may be important in determining the interactions of this pest with the environment and with conspecifics. These results also have applied relevance to increase the mating competitiveness of mass-reared C. capitata used in Sterile Insect Technique programs.

Expression of an Intestine-Specific Transcription Factor (CDX1) in Intestinal Metaplasia and in Subsequently Developed Intestinal Type of Cholangiocarcinoma in Rat Liver

PubMed Central

Ren, Ping; Silberg, Debra G.; Sirica, Alphonse E.

2000-01-01

CDX1 is a caudal-type homeobox intestine-specific transcription factor that has been shown to be selectively expressed in epithelial cells in intestinal metaplasia of the human stomach and esophagus and variably expressed in human gastric and esophageal adenocarcinomas (Silberg DG, Furth EE, Taylor JK, Schuck T, Chiou T, Traber PG: Gastroenterology 1997, 113: 478–486). Through the use of immunohistochemistry and Western blotting, we investigated whether CDX1 is also uniquely associated with the intestinal metaplasia associated with putative precancerous cholangiofibrosis induced in rat liver during furan cholangiocarcinogenesis, as well as expressed in neoplastic glands in a subsequently developed intestinal type of cholangiocarcinoma. In normal, control adult rat small intestine, specific nuclear immunoreactivity for CDX1 was most prominent in enterocytes lining the crypts. In comparison, epithelium from intestinal metaplastic glands within furan-induced hepatic cholangiofibrosis and neoplastic epithelium from later developed primary intestinal-type cholangiocarcinoma each demonstrated strong nuclear immunoreactivity for CDX1. CDX1-positive cells were detected in hepatic cholangiofibrotic tissue as early as 3 weeks after the start of chronic furan treatment. We further determined that the percentages of CDX1-positive neoplastic glands and glandular nuclei are significantly higher in primary tumors than in a derived, transplantable cholangiocarcinoma serially-propagated in vivo. Western blotting confirmed our immunohistochemical results, and no CDX1 immunoreactivity was detected in normal adult rat liver or in hyperplastic biliary epithelial cells. These findings indicate that CDX1 is specifically associated with early intestinal metaplasia and a later developed intestinal-type of cholangiocarcinoma induced in the liver of furan-treated rats. PMID:10666391

Evidence for the Involvement of p38 MAPK Activation in Barnacle Larval Settlement

PubMed Central

He, Li-Sheng; Xu, Ying; Matsumura, Kiyotaka; Zhang, Yu; Zhang, Gen; Qi, Shu-Hua; Qian, Pei-Yuan

2012-01-01

The barnacle Balanus ( = Amphibalanus) amphitrite is a major marine fouling animal. Understanding the molecular mechanism of larval settlement in this species is critical for anti-fouling research. In this study, we cloned one isoform of p38 MAPK (Bar-p38 MAPK) from this species, which shares the significant characteristic of containing a TGY motif with other species such as yeast, Drosophila and humans. The activation of p38 MAPK was detected by an antibody that recognizes the conserved dual phosphorylation sites of TGY. The results showed that phospho-p38 MAPK (pp38 MAPK) was more highly expressed at the cyprid stage, particularly in aged cyprids, in comparison to other stages, including the nauplius and juvenile stages. Immunostaining showed that Bar-p38 MAPK and pp38 MAPK were mainly located at the cyprid antennules, and especially the third and fourth segments, which are responsible for substratum exploration during settlement. The expression and localization patterns of Bar-p38 MAPK suggest its involvement in larval settlement. This postulation was also supported by the larval settlement bioassay with the p38 MAPK inhibitor SB203580. Behavioral analysis by live imaging revealed that the larvae were still capable of exploring the surface of the substratum after SB203580 treatment. This shows that the effect of p38 MAPK on larval settlement might be by regulating the secretion of permanent proteinaceous substances. Furthermore, the level of pp38 MAPK dramatically decreased after full settlement, suggesting that Bar-p38 MAPK maybe plays a role in larval settlement rather than metamorphosis. Finally, we found that Bar-p38 MAPK was highly activated when larvae confronted extracts of adult barnacle containing settlement cues, whereas larvae pre-treated with SB203580 failed to respond to the crude adult extracts. PMID:23115639

[Persistence [corrected] of onphalomesenteric duct as intestinal obstruction cause in a adult. Report of a case in the Hipolito Unanue Nacional Hospital].

PubMed

Gutiérrez Ccencho, C; Luna Cydejko, Jc; Gutierrez De Aranguren, Cf; Revoredo, Fernando; Soto Tarazona, A; Olazábal Ramírez, V

2008-01-01

The persistence of the onphalomesenteric duct has been reported in several pediatric publications either through the appearance of Meckel diverticulum that are commonest, or by the appearance of segments with partial or total permeability of itself. Sporadic cases have appeared where this anomaly has originated episodes of intestinal obstruction in infants and children specially under the form of a fibrous band. However, adult presentations extremely infrequent. The case presented in this report shows compatible findings with a onphalomesenteric conduit with partial permeability, that I originate an intestinal picture of obstruction in a young adult.

Clinical Implications and Pathogenesis of Esophageal Remodeling in Eosinophilic Esophagitis

PubMed Central

Hirano, Ikuo; Aceves, Seema S.

2014-01-01

In eosinophilic esophagitis (EoE), remodeling changes are manifest histologically in both the epithelium as well as in the subepithelium where lamina propria (LP) fibrosis, expansion of the muscularis propria and increased vascularity occur. The major clinical symptoms and complications of EoE are largely consequences of esophageal remodeling. Important mediators of the process include IL-5, IL-13, TGFβ1, mast cells, fibroblasts and eosinophils. Methods to detect remodeling effects include upper endoscopy, histopathology, barium esophagram, endoscopic ultrasonography, esophageal manometry, and functional luminal imaging. These modalities provide evidence of organ dysfunction that include focal and diffuse esophageal strictures, expansion of the mucosa and subepithelium, esophageal motor abnormalities and reduced esophageal distensibility. Complications of food impaction and perforations of the esophageal wall have been associated with reduction in esophageal caliber and increased esophageal mural stiffness. The therapeutic benefits of topical corticosteroids and elimination diet therapy in resolving mucosal eosinophilic inflammation of the esophagus are evident. Available therapies, however, have demonstrated variable ability to reverse existing remodeling changes of the esophagus. Systemic therapies that include novel, targeted biologic agents have the potential of addressing subepithelial remodeling. Esophageal dilation remains a useful, adjunctive therapeutic maneuver in symptomatic adults with esophageal stricture. As novel treatments emerge, it is essential that therapeutic endpoints account for the fundamental contributions of esophageal remodeling to overall disease activity. PMID:24813517

Laparoscopic surgery for colon cancer with intestinal malrotation in adults: Two case reports and review of literatures in Japan.

PubMed

Nakatani, Kazuyoshi; Tokuhara, Katsuji; Sakaguchi, Tatsuma; Yoshioka, Kazuhiko; Kon, Masanori

2017-01-01

Intestinal malrotation is a congenital anomaly, and its occurrence in adults is rare. Colon cancer with intestinal malrotation is far more rare. We herein report two cases of colon cancer with intestinal malrotation treated with laparoscopic surgery and reviewed the literatures in Japan. Case 1 involved a 78-year-old man. Abdominal enhanced computed tomography (CT) showed that the tumor was located in the sigmoid colon. Intraoperatively, the cecum and ascending colon were located along the midline and the small intestine occupied the right side of the abdomen. The tumor was located in the cecum, and the patient was diagnosed with cecal cancer with intestinal malrotation. We performed laparoscopy-assisted ileocecal resection. Case 2 involved a 81-year-old man. Colonoscopy revealed a laterally spreading tumor in the cecum. Intraoperatively, the position of the small intestine and the ascending colon was similar to case 1, and Ladd's band was found in front of the duodenum. Thus, we diagnosed the patient with a laterally spreading cecal tumor with intestinal malrotation and performed laparoscopy-assisted ileocecal resection. A review of the literature revealed 49 cases of colon cancer with intestinal malrotation and laparoscopic surgery performed at 30.6%. If laparoscopic mesenteric excision for colon cancer with intestinal malrotation is unsafe because of the abnormalities of the artery, mesenteric excision should be performed outside the body. If the intestinal malrotation is diagnosed preoperatively, 3D-CT angiography should be used to reveal the vascular anatomic anomalies for safe performance of laparoscopic surgery. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

Small nonnative fishes as predators of larval razorback suckers

USGS Publications Warehouse

Carpenter, J.; Mueller, G.A.

2008-01-01

The razorback sucker (Xyrauchen texanus), an endangered big-river fish of the Colorado River basin, has demonstrated no sustainable recruitment in 4 decades, despite presence of spawning adults and larvae. Lack of adequate recruitment has been attributed to several factors, including predation by nonnative fishes. Substantial funding and effort has been expended on mechanically removing nonnative game fishes, typically targeting large predators. As a result, abundance of larger predators has declined, but the abundance of small nonnative fishes has increased in some areas. We conducted laboratory experiments to determine if small nonnative fishes would consume larval razorback suckers. We tested adults of three small species (threadfin shad, Dorosoma petenense; red shiner, Cyprinella lutrensis; fathead minnow, Pimephales promelas) and juveniles of six larger species (common carp, Cyprinus carpio; yellow bullhead, Ameiurus natalis; channel catfish, Ictalurus punctatus; rainbow trout, Oncorhynchus mykiss; green sunfish, Lepomis cyanellus; bluegill, L. macrochirus). These nonnative fishes span a broad ecological range and are abundant within the historical range of the razorback sucker. All nine species fed on larval razorback suckers (total length, 9-16 mm). Our results suggest that predation by small nonnative fishes could be responsible for limiting recovery of this endangered species.

Spinal motor neurons are regenerated after mechanical lesion and genetic ablation in larval zebrafish.

PubMed

Ohnmacht, Jochen; Yang, Yujie; Maurer, Gianna W; Barreiro-Iglesias, Antón; Tsarouchas, Themistoklis M; Wehner, Daniel; Sieger, Dirk; Becker, Catherina G; Becker, Thomas

2016-05-01

In adult zebrafish, relatively quiescent progenitor cells show lesion-induced generation of motor neurons. Developmental motor neuron generation from the spinal motor neuron progenitor domain (pMN) sharply declines at 48 hours post-fertilisation (hpf). After that, mostly oligodendrocytes are generated from the same domain. We demonstrate here that within 48 h of a spinal lesion or specific genetic ablation of motor neurons at 72 hpf, the pMN domain reverts to motor neuron generation at the expense of oligodendrogenesis. By contrast, generation of dorsal Pax2-positive interneurons was not altered. Larval motor neuron regeneration can be boosted by dopaminergic drugs, similar to adult regeneration. We use larval lesions to show that pharmacological suppression of the cellular response of the innate immune system inhibits motor neuron regeneration. Hence, we have established a rapid larval regeneration paradigm. Either mechanical lesions or motor neuron ablation is sufficient to reveal a high degree of developmental flexibility of pMN progenitor cells. In addition, we show an important influence of the immune system on motor neuron regeneration from these progenitor cells. © 2016. Published by The Company of Biologists Ltd.

Reduction in deformed wing virus infection in larval and adult honey bees (Apis mellifera L.) by double-stranded RNA ingestion.

PubMed

Desai, S D; Eu, Y-J; Whyard, S; Currie, R W

2012-08-01

Deformed wing virus (DWV) is a serious pathogen of the honey bee, Apis mellifera L., vectored by the parasitic mite Varroa destructor. The virus is associated with wing deformity in symptomatic bees, and premature death and reduced colony performance in asymptomatic bees. In the present study we reduced DWV infection by feeding both first instar larvae and adult A. mellifera with a double-stranded (ds) RNA construct, DWV-dsRNA, which is specific to DWV in DWV-inoculated bees, by mixing it with their food. We showed that feeding DWV to larvae causes wing deformity in adult bees in the absence of varroa mites and decreases survival rates of adult bees relative to bees not fed DWV. Feeding larvae with DWV-dsRNA in advance of inoculation with virus reduced the DWV viral level and reduced wing deformity relative to larvae fed DWV or DWV with green fluorescent protein-dsRNA (probably a result of RNA silencing), but did not affect survival to the adult stage. Feeding DWV-dsRNA did not affect larval survival rates, which suggests that dsRNA is non-toxic to larvae. Feeding adult workers with DWV-dsRNA in advance of inoculation with virus increased their longevity and reduced DWV concentration relative to controls. © 2012 The Authors. Insect Molecular Biology © 2012 The Royal Entomological Society.

Hypothalamic Projections to the Optic Tectum in Larval Zebrafish.

PubMed

Heap, Lucy A; Vanwalleghem, Gilles C; Thompson, Andrew W; Favre-Bulle, Itia; Rubinsztein-Dunlop, Halina; Scott, Ethan K

2017-01-01

The optic tectum of larval zebrafish is an important model for understanding visual processing in vertebrates. The tectum has been traditionally viewed as dominantly visual, with a majority of studies focusing on the processes by which tectal circuits receive and process retinally-derived visual information. Recently, a handful of studies have shown a much more complex role for the optic tectum in larval zebrafish, and anatomical and functional data from these studies suggest that this role extends beyond the visual system, and beyond the processing of exclusively retinal inputs. Consistent with this evolving view of the tectum, we have used a Gal4 enhancer trap line to identify direct projections from rostral hypothalamus (RH) to the tectal neuropil of larval zebrafish. These projections ramify within the deepest laminae of the tectal neuropil, the stratum album centrale (SAC)/stratum griseum periventriculare (SPV), and also innervate strata distinct from those innervated by retinal projections. Using optogenetic stimulation of the hypothalamic projection neurons paired with calcium imaging in the tectum, we find rebound firing in tectal neurons consistent with hypothalamic inhibitory input. Our results suggest that tectal processing in larval zebrafish is modulated by hypothalamic inhibitory inputs to the deep tectal neuropil.

Optimizing larval assessment to support sea lamprey control in the Great Lakes

USGS Publications Warehouse

Hansen, Michael J.; Adams, Jean V.; Cuddy, Douglas W.; Richards, Jessica M.; Fodale, Michael F.; Larson, Geraldine L.; Ollila, Dale J.; Slade, Jeffrey W.; Steeves, Todd B.; Young, Robert J.; Zerrenner, Adam

2003-01-01

Elements of the larval sea lamprey (Petromyzon marinus) assessment program that most strongly influence the chemical treatment program were analyzed, including selection of streams for larval surveys, allocation of sampling effort among stream reaches, allocation of sampling effort among habitat types, estimation of daily growth rates, and estimation of metamorphosis rates, to determine how uncertainty in each element influenced the stream selection program. First, the stream selection model based on current larval assessment sampling protocol significantly underestimated transforming sea lam-prey abundance, transforming sea lampreys killed, and marginal costs per sea lamprey killed, compared to a protocol that included more years of data (especially for large streams). Second, larval density in streams varied significantly with Type-I habitat area, but not with total area or reach length. Third, the ratio of larval density between Type-I and Type-II habitat varied significantly among streams, and that the optimal allocation of sampling effort varied with the proportion of habitat types and variability of larval density within each habitat. Fourth, mean length varied significantly among streams and years. Last, size at metamorphosis varied more among years than within or among regions and that metamorphosis varied significantly among streams within regions. Study results indicate that: (1) the stream selection model should be used to identify streams with potentially high residual populations of larval sea lampreys; (2) larval sampling in Type-II habitat should be initiated in all streams by increasing sampling in Type-II habitat to 50% of the sampling effort in Type-I habitat; and (3) methods should be investigated to reduce uncertainty in estimates of sea lamprey production, with emphasis on those that reduce the uncertainty associated with larval length at the end of the growing season and those used to predict metamorphosis.

Evolution of larval competitiveness and associated life-history traits in response to host shifts in a seed beetle.

PubMed

Fox, C W; Messina, F J

2018-02-01

Resource competition is frequently strong among parasites that feed within small discrete resource patches, such as seeds or fruits. The properties of a host can influence the behavioural, morphological and life-history traits of associated parasites, including traits that mediate competition within the host. For seed parasites, host size may be an especially important determinant of competitive ability. Using the seed beetle, Callosobruchus maculatus, we performed replicated, reciprocal host shifts to examine the role of seed size in determining larval competitiveness and associated traits. Populations ancestrally associated with either a small host (mung bean) or a large one (cowpea) were switched to each other's host for 36 generations. Compared to control lines (those remaining on the ancestral host), lines switched from the small host to the large host evolved greater tolerance of co-occurring larvae within seeds (indicated by an increase in the frequency of small seeds yielding two adults), smaller egg size and higher fecundity. Each change occurred in the direction predicted by the traits of populations already adapted to cowpea. However, we did not observe the expected decline in adult mass following the shift to the larger host. Moreover, lines switched from the large host (cowpea) to the small host (mung bean) did not evolve the predicted increase in larval competitiveness or egg size, but did exhibit the predicted increase in body mass. Our results thus provide mixed support for the hypothesis that host size determines the evolution of competition-related traits of seed beetles. Evolutionary responses to the two host shifts were consistent among replicate lines, but the evolution of larval competition was asymmetric, with larval competitiveness evolving as predicted in one direction of host shift, but not the reverse. Nevertheless, our results indicate that switching hosts is sufficient to produce repeatable and rapid changes in the competition strategy

Premature remodeling of fat body and fat mobilization triggered by platelet-derived growth factor/VEGF receptor in Drosophila.

PubMed

Zheng, Huimei; Wang, Xuexiang; Guo, Pengfei; Ge, Wanzhong; Yan, Qinfeng; Gao, Weiqiang; Xi, Yongmei; Yang, Xiaohang

2017-05-01

In Drosophila, fat-body remodeling accompanied with fat mobilization is an ecdysone-induced dynamic process that only occurs during metamorphosis. Here, we show that the activated Drosophila platelet-derived growth factor/VEGF receptor (PVR) is sufficient to induce shape changes in the fat body, from thin layers of tightly conjugated polygonal cells to clusters of disaggregated round-shaped cells. These morphologic changes are reminiscent of those seen during early pupation upon initiation of fat-body remodeling. Activation of PVR also triggers an early onset of lipolysis and mobilization of internal storage, as revealed by the appearance of small lipid droplets and up-regulated lipolysis-related genes. We found that PVR displays a dynamic expression pattern in the fat body and peaks at the larval-prepupal transition under the control of ecdysone signaling. Removal of PVR, although it does not prevent ecdysone-induced fat-body remodeling, causes ecdysone signaling to be up-regulated. Our data reveal that PVR is active in a dual-secured mechanism that involves an ecdysone-induced fat-body remodeling pathway and a reinforced PVR pathway for effective lipid mobilization. Ectopic expression of activated c-kit-the mouse homolog of PVR in the Drosophila fat body-also results in a similar phenotype. This may suggest a novel function of c-kit as it relates to lipid metabolism in mammals.-Zheng, H., Wang, X., Guo, P., Ge, W., Yan, Q., Gao, W., Xi, Y., Yang, X. Premature remodeling of fat body and fat mobilization triggered by platelet-derived growth factor/VEGF receptor in Drosophila . © FASEB.

Lyophilized airborne Clostridium botulinum spores as inocula that intestinally colonize antimicrobially pretreated adult mice.

PubMed Central

Sugiyama, H; Prather, J L; Woller, M J

1986-01-01

Adult mice, made susceptible to Clostridium botulinum by feedings of metronidazole, were immobilized with an anesthetic and held for 30 min in isolators in which a fine powder of lyophilized pathogen spores was made airborne. Exposed mice were surface decontaminated before being kept for 2 days in holding isolators. Mice were intestinally colonized by the pathogen. Colonization rates were related to spore numbers (10(4) to 10(7) type A or B) seeded into isolators. PMID:3531017

CorMatrix valved conduit in a porcine model: long-term remodelling and biomechanical characterization.

PubMed

Mosala Nezhad, Zahra; Poncelet, Alain; de Kerchove, Laurent; Fervaille, Caroline; Banse, Xavier; Bollen, Xavier; Dehoux, Jean-Paul; El Khoury, Gebrine; Gianello, Pierre

2017-01-01

Porcine small intestinal submucosa extracellular matrix (CorMatrix; CorMatrix Cardiovascular, Rosewell, GA) is a relatively novel tissue substitute used in cardiovascular applications. We investigated the biological reaction and remodelling of CorMatrix as a tri-leaflet valved conduit in a pig model. We hypothesized that CorMatrix maintains a durable architecture as a valved conduit and remodels to resemble surrounding tissues. We fashioned the valved conduit using a 7 × 10 cm 4-ply CorMatrix sheet and placed it in the thoracic aorta of seven landrace pigs for 3, 4, 5 and 6 months. Biodegradation, replacement by native tissue, strength and durability were examined by histology, immunohistochemistry and mechanical testing. Four pigs, one per time frame, completed the study. The conduit lost its original architecture as a tri-leaflet valve due to cusp immobility, subsequent attachment to the wall segment and consequent maintenance of a thick arterial wall-like structure. Scaffold resorption was incomplete, with disorganized inconsistent spatial and temporal degradation even at 6 months. Fibrosis, scarring and calcification started at 4 months and chronic inflammation persisted. The partially remodelled scaffold did not resemble the aortic wall, suggesting impaired remodelling. Mechanical testing showed progressive weakening of the tissues over time, which were liable to breakage. CorMatrix is biodegradable; however, it failed to remodel in a structured and anatomical fashion in an arterial environment. Progressive mechanical and remodelling failure in this scenario might be explained by the complexity of the conduit design and the host's chronic inflammatory response, leading to early fibrosis and calcification. © The Author 2016. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.

The Intrauterine and Nursing Period Is a Window of Susceptibility for Development of Obesity and Intestinal Tumorigenesis by a High Fat Diet in Min/+ Mice as Adults

PubMed Central

Ngo, Ha Thi; Hetland, Ragna Bogen; Steffensen, Inger-Lise

2015-01-01

We studied how obesogenic conditions during various life periods affected obesity and intestinal tumorigenesis in adult C57BL/6J-Min (multiple intestinal neoplasia)/+ mice. The mice were given a 10% fat diet throughout life (negative control) or a 45% fat diet in utero, during nursing, during both in utero and nursing, during adult life, or during their whole life-span, and terminated at 11 weeks for tumorigenesis (Min/+) or 23 weeks for obesogenic effect (wild-type). Body weight at 11 weeks was increased after a 45% fat diet during nursing, during both in utero and nursing, and throughout life, but had normalized at 23 weeks. In the glucose tolerance test, the early exposure to a 45% fat diet in utero, during nursing, or during both in utero and nursing, did not affect blood glucose, whereas a 45% fat diet given to adults or throughout life did. However, a 45% fat diet during nursing or during in utero and nursing increased the number of small intestinal tumors. So did exposures to a 45% fat diet in adult life or throughout life, but without increasing the tumor numbers further. The intrauterine and nursing period is a window of susceptibility for dietary fat-induced obesity and intestinal tumor development. PMID:25874125

Changes in intestinal microbiota composition and metabolism coincide with increased intestinal permeability in young adults under prolonged physiological stress.

PubMed

Karl, J Philip; Margolis, Lee M; Madslien, Elisabeth H; Murphy, Nancy E; Castellani, John W; Gundersen, Yngvar; Hoke, Allison V; Levangie, Michael W; Kumar, Raina; Chakraborty, Nabarun; Gautam, Aarti; Hammamieh, Rasha; Martini, Svein; Montain, Scott J; Pasiakos, Stefan M

2017-06-01

The magnitude, temporal dynamics, and physiological effects of intestinal microbiome responses to physiological stress are poorly characterized. This study used a systems biology approach and a multiple-stressor military training environment to determine the effects of physiological stress on intestinal microbiota composition and metabolic activity, as well as intestinal permeability (IP). Soldiers ( n = 73) were provided three rations per day with or without protein- or carbohydrate-based supplements during a 4-day cross-country ski-march (STRESS). IP was measured before and during STRESS. Blood and stool samples were collected before and after STRESS to measure inflammation, stool microbiota, and stool and plasma global metabolite profiles. IP increased 62 ± 57% (mean ± SD, P < 0.001) during STRESS independent of diet group and was associated with increased inflammation. Intestinal microbiota responses were characterized by increased α-diversity and changes in the relative abundance of >50% of identified genera, including increased abundance of less dominant taxa at the expense of more dominant taxa such as Bacteroides Changes in intestinal microbiota composition were linked to 23% of metabolites that were significantly altered in stool after STRESS. Together, pre-STRESS Actinobacteria relative abundance and changes in serum IL-6 and stool cysteine concentrations accounted for 84% of the variability in the change in IP. Findings demonstrate that a multiple-stressor military training environment induced increases in IP that were associated with alterations in markers of inflammation and with intestinal microbiota composition and metabolism. Associations between IP, the pre-STRESS microbiota, and microbiota metabolites suggest that targeting the intestinal microbiota could provide novel strategies for preserving IP during physiological stress. NEW & NOTEWORTHY Military training, a unique model for studying temporal dynamics of intestinal barrier and intestinal

Larval competition of Chrysomya megacephala and Chrysomya rufifacies (Diptera: Calliphoridae): behavior and ecological studies of two blow fly species of forensic significance.

PubMed

Shiao, Shiuh-Feng; Yeh, Ta-Chuan

2008-07-01

Chrysomya megacephala and Chrysomya rufifacies are two predominant necrophagous species in Taiwan. Larvae of the latter can prey on other maggots, including that of their own species as facultative food. This facultative characteristic of C. rufifacies may enhance its competitive advantage over other maggots and could also change the situation of other coexisting colonies. In this study, these two species were colonized in the laboratory, and the main objective was to try to understand the effect of competition on larval development. According to our results, intraspecific competition mostly occurred as competition for food; when the rearing density was increased, larvae pupated earlier, resulting in a lighter adult dry weight. The tendencies were similar in both species, but C. megacephala developed smaller viable adults and had higher survivorship at high densities. Although C. rufifacies could use the food resource of cannibalism, its survivorship was still low. Our results also showed there were significant interactions between intraspecific competition and the density factor. However, with interspecific competition, the first-instar larvae of C. rufifacies invaded maggot masses of C. megacephala to feed together. The third instars of C. rufifacies were able to expel C. megacephala larvae from food by using a fleshy protrusion on their body surface; C. megacephala was usually forced to pupate earlier by shortening its larval stages. The results indicated that a temporary competitive advantage could only be obtained by C. rufifacies under a proper larval density. In addition, the effects on different larval stages, the responses to different competition intensities, and the temperature-dependent effects on interspecific competition are also discussed. In general, under mixed-species rearing at different temperatures and densities, larval duration, adult dry weight, and survivorship of both species decreased. However, our results did not completely agree with

The effect of larval nutritional deprivation on the life history and DDT resistance phenotype in laboratory strains of the malaria vector Anopheles arabiensis

PubMed Central

2013-01-01

Background Anopheles arabiensis is a major malaria vector in Africa. It thrives in agricultural areas and has been associated with increased malaria incidence in areas under rice and maize cultivation. This effect may be due to increased adult size and abundance as a consequence of optimal larval nutrition. The aim of this study was to examine the effect of larval nutrition on the life history and expression of insecticide resistance in adults of laboratory reared An. arabiensis. Methods Larvae drawn from an insecticide susceptible An. arabiensis strain (SENN) as well as a DDT-resistant strain (SENN-DDT) were subjected to three fasting regimes: 1 mg of food per larva offered once per day, once every second day and once every third day. Control cohorts included larvae offered 1 mg food thrice per day. The rate of larval development was compared between matched cohorts from each strain as well as between fasted larvae and their respective controls. The expression of DDT resistance/tolerance in adults was compared between the starved cohorts and their controls by strain. Factors potentially affecting variation in DDT resistance/tolerance were examined including: adult body size (wing length), knock-down resistance (kdr) status and levels of detoxification enzyme activity. Results and conclusion Anopheles arabiensis larval development is prolonged by nutrient deprivation and adults that eclose from starved larvae are smaller and less tolerant to DDT intoxication. This effect on DDT tolerance in adults is also associated with reduced detoxification enzyme activity. Conversely, well fed larvae develop comparatively quickly into large, more DDT tolerant (SENN) or resistant (SENN-DDT) adults. This is important in those instances where cereal farming is associated with increased An. arabiensis transmitted malaria incidence, because large adult females with high teneral reserves and decreased susceptibility to insecticide intoxication may also prove to be more

Intestinal lymphosarcoma in captive African hedgehogs.

PubMed

Raymond, J T; Clarke, K A; Schafer, K A

1998-10-01

Two captive adult female African hedgehogs (Atelerix albiventris) had inappetance and bloody diarrhea for several days prior to death. Both hedgehogs had ulceration of the small intestine and hepatic lipidosis. Histopathology revealed small intestinal lymphosarcoma with metastasis to the liver. Extracellular particles that had characteristics of retroviruses were observed associated with the surface of some neoplastic lymphoid cells by transmission electron microscopy. These are the first reported cases of intestinal lymphosarcoma in African hedgehogs.

Bioecology of Stenoma catenifer (Lepidoptera: Elachistidae) and associated larval parasitoids reared from Hass avocados in Guatemala.

PubMed

Hoddle, Mark S; Hoddle, Christina D

2008-06-01

A 10-wk study of the avocado seed-feeding moth Stenoma catenifer Walsingham (Lepidoptera: Elachistidae), was conducted in a commercial 'Hass' avocado (Persea americana Miller [Lauraceae]) orchard in Guatemala. Up to 45% of fruit in the orchard were damaged by larval S. catenifer. Larval-to-adult survivorship for 1,881 S. catenifer larvae in Hass fruit was 37%, and adult sex ratio was 51% female. Four species of larval parasitoid were reared from field-collected S. catenifer larvae. The most common parasitoid reared was a gregarious Apanteles sp., which parasitized 53% of larvae and produced on average eight to nine cocoons per host. Apanteles sp. sex ratio was 47% female and 87% of parasitoids emerged successfully from cocoons. Apanteles sp. longevity was approximately equal to 1.5 d in the absence of food, and when provisioned with honey, parasitoids survived for 5-7 d. The mean number of cocoons produced by Apanteles sp. per host, and larval parasitism rates were not significantly affected by the number of S. catenifer larvae inhabiting seeds. Oviposition studies conducted with S. catenifer in the laboratory indicated that this moth lays significantly more eggs on the branch to which the fruit pedicel is attached than on avocado fruit. When given a choice between Hass and non-Hass avocados, S. catenifer lays up to 2.69 times more eggs on Hass.

Hypothalamic Projections to the Optic Tectum in Larval Zebrafish

PubMed Central

Heap, Lucy A.; Vanwalleghem, Gilles C.; Thompson, Andrew W.; Favre-Bulle, Itia; Rubinsztein-Dunlop, Halina; Scott, Ethan K.

2018-01-01

The optic tectum of larval zebrafish is an important model for understanding visual processing in vertebrates. The tectum has been traditionally viewed as dominantly visual, with a majority of studies focusing on the processes by which tectal circuits receive and process retinally-derived visual information. Recently, a handful of studies have shown a much more complex role for the optic tectum in larval zebrafish, and anatomical and functional data from these studies suggest that this role extends beyond the visual system, and beyond the processing of exclusively retinal inputs. Consistent with this evolving view of the tectum, we have used a Gal4 enhancer trap line to identify direct projections from rostral hypothalamus (RH) to the tectal neuropil of larval zebrafish. These projections ramify within the deepest laminae of the tectal neuropil, the stratum album centrale (SAC)/stratum griseum periventriculare (SPV), and also innervate strata distinct from those innervated by retinal projections. Using optogenetic stimulation of the hypothalamic projection neurons paired with calcium imaging in the tectum, we find rebound firing in tectal neurons consistent with hypothalamic inhibitory input. Our results suggest that tectal processing in larval zebrafish is modulated by hypothalamic inhibitory inputs to the deep tectal neuropil. PMID:29403362

Regulation of bone remodeling by vitamin K2.

PubMed

Myneni, V D; Mezey, E

2017-11-01

All living tissues require essential nutrients such as amino acids, fatty acids, carbohydrates, minerals, vitamins, and water. The skeleton requires nutrients for development, maintaining bone mass and density. If the skeletal nutritional requirements are not met, the consequences can be quite severe. In recent years, there has been growing interest in promotion of bone health and inhibition of vascular calcification by vitamin K2. This vitamin regulates bone remodeling, an important process necessary to maintain adult bone. Bone remodeling involves removal of old or damaged bone by osteoclasts and its replacement by new bone formed by osteoblasts. The remodeling process is tightly regulated, when the balance between bone resorption and bone formation shifts to a net bone loss results in the development of osteoporosis in both men and women. In this review, we focus on our current understanding of the effects of vitamin K2 on bone cells and its role in prevention and treatment of osteoporosis. Published 2016. This article is a U.S. Government work and is in the public domain in the USA.

Rapid Effects of Marine Reserves via Larval Dispersal

PubMed Central

Cudney-Bueno, Richard; Lavín, Miguel F.; Marinone, Silvio G.; Raimondi, Peter T.; Shaw, William W.

2009-01-01

Marine reserves have been advocated worldwide as conservation and fishery management tools. It is argued that they can protect ecosystems and also benefit fisheries via density-dependent spillover of adults and enhanced larval dispersal into fishing areas. However, while evidence has shown that marine reserves can meet conservation targets, their effects on fisheries are less understood. In particular, the basic question of if and over what temporal and spatial scales reserves can benefit fished populations via larval dispersal remains unanswered. We tested predictions of a larval transport model for a marine reserve network in the Gulf of California, Mexico, via field oceanography and repeated density counts of recently settled juvenile commercial mollusks before and after reserve establishment. We show that local retention of larvae within a reserve network can take place with enhanced, but spatially-explicit, recruitment to local fisheries. Enhancement occurred rapidly (2 yrs), with up to a three-fold increase in density of juveniles found in fished areas at the downstream edge of the reserve network, but other fishing areas within the network were unaffected. These findings were consistent with our model predictions. Our findings underscore the potential benefits of protecting larval sources and show that enhancement in recruitment can be manifested rapidly. However, benefits can be markedly variable within a local seascape. Hence, effects of marine reserve networks, positive or negative, may be overlooked when only focusing on overall responses and not considering finer spatially-explicit responses within a reserve network and its adjacent fishing grounds. Our results therefore call for future research on marine reserves that addresses this variability in order to help frame appropriate scenarios for the spatial management scales of interest. PMID:19129910

Modification of a Volume-Overload Heart Failure Model to Track Myocardial Remodeling and Device-Related Reverse Remodeling

PubMed Central

Tuzun, Egemen; Bick, Roger; Kadipasaoglu, Cihan; Conger, Jeffrey L.; Poindexter, Brian J.; Gregoric, Igor D.; Frazier, O. H.; Towbin, Jeffrey A.; Radovancevic, Branislav

2011-01-01

Purpose. To provide an ovine model of ventricular remodeling and reverse remodeling by creating congestive heart failure (CHF) and then treating it by implanting a left ventricular assist device (LVAD). Methods. We induced volume-overload heart failure in 2 sheep; 20 weeks later, we implanted an LVAD and assessed recovery 11 weeks thereafter. We examined changes in histologic and hemodynamic data and levels of cellular markers of CHF. Results. After CHF induction, we found increases in LV end-diastolic pressure, LV systolic and diastolic dimensions, wall thickness, left atrial diameter, and atrial natriuretic protein (ANP) and endothelin-1 (ET-1) levels; β-adrenergic receptor (BAR) and dystrophin expression decreased markedly. Biopsies confirmed LV remodeling. After LVAD support, LV systolic and diastolic dimensions, wall thickness, and mass, and ANP and ET-1 levels decreased. Histopathologic and hemodynamic markers improved, and BAR and dystrophin expression normalized. Conclusions. We describe a successful sheep model for ventricular and reverse remodeling. PMID:22347659

Inducible Intestine-specific Deletion Of Krüppel-Like Factor 5 Is Characterized By A Regenerative Response In Adult Mouse Colon

PubMed Central

Nandan, Mandayam O.; Ghaleb, Amr M.; Liu, Yang; Bialkowska, Agnieszka B.; McConnell, Beth B.; Shroyer, Kenneth R.; Robine, Sylvie

2014-01-01

Krüppel-like factor 5 (KLF5) is a pro-proliferative transcriptional regulator primarily expressed in the intestinal crypt epithelial cells. Constitutive intestine-specific deletion of Klf5 is neonatal lethal suggesting a crucial role for KLF5 in intestinal development and homeostasis. We have previously shown Klf5 to play an active role regulating intestinal tumorigenesis. Here we examine the effect of inducible intestine-specific deletion of Klf5 in adult mice. Klf5 is lost from the intestine beginning at day 3 after the start of a 5-day treatment with the inducer tamoxifen. Although the mice have no significant weight loss or lethality, the colonic tissue shows signs of epithelial distress starting at day 3 following induction. Accompanying the morphological changes is a significant loss of proliferative crypt epithelial cells as revealed by BrdU or Ki67 staining at days 3 & 5 after start of tamoxifen. We also observed a loss of goblet cells from the colon and Paneth cells from the small intestine upon induced deletion of Klf5. In addition, loss of Klf5 from the colonic epithelium is accompanied by a regenerative response that coincides with an expansion in the zone of Sox9 expression along the crypt axis. At day 11, both proliferation and Sox9 expression return to baseline levels. Microarray and quantitative PCR analyses reveal an upregulation of several regeneration-associated genes (Reg1A, Reg3G and Reg3B) and down-regulation of many Klf5 targets (Ki-67, cyclin B, Cdc2 and cyclin D1). Sox9 and Reg1A protein levels are also increased upon Klf5 loss. Lentiviral-mediated knockdown of KLF5 and exogenous expression of KLF5 in colorectal cancer cell lines confirm that Sox9 expression is negatively regulated by KLF5. Furthermore, ChIP assays reveal a direct association of KLF5 with both the Sox9 and Reg1A promoters. We have shown that disruption of epithelial homeostasis due to Klf5 loss from the adult colon is followed by a regenerative response led by Sox9 and the

Treatment of Intestinal Helminths Does Not Reduce Plasma Concentrations of HIV-1 RNA in Coinfected Zambian Adults

PubMed Central

Modjarrad, Kayvon; Zulu, Isaac; Redden, David T.; Njobvu, Lungowe; Lane, H. Clifford; Bentwich, Zvi; Vermund, Sten H.

2009-01-01

Background Infection with intestinal helminths may stimulate dysfunctional immune responses in human immunodeficiency virus (HIV)–infected persons. Studies have yielded conflicting results regarding the impact of antihelminthic treatment on plasma concentrations of HIV-1 RNA. Methods We conducted a prospective study of 54 HIV-1– and helminth-coinfected and 57 HIV-1–infected, helminth-uninfected asymptomatic adults living in Lusaka, Zambia, to assess the impact of antihelminthic treatment on plasma concentrations of HIV-1 RNA. Results Median baseline viral load was 0.33 log10 copies/mL lower in the helminth-infected group than in the uninfected group. Mean viral load between pretreatment and posttreatment visits increased in the helminth-infected (mean, 4.23 vs. 4.29 log10 copies/mL; P = .6) and helminth-uninfected (mean, 4.39 vs. 4.52 log10 copies/mL; P = .2) groups. Helminth-infected participants with high pretreatment viral loads had a mean 0.25-log10 copies/mL decrease after treatment (P = .3), and helminth-uninfected participants had a mean 0.02-log10 copies/mL decrease (P = .8). Conclusions We did not find an overall association between treatment of intestinal helminth infections and reduction in viral load in coinfected adults. Future studies may need to focus on adults with intense helminth infections who live in rural areas or on adults or children who harbor higher helminth burdens and plasma concentrations of HIV-1 RNA. PMID:16136473

Staggered larval time-to-hatch and insecticide resistance in the major malaria vector Anopheles gambiae S form.

PubMed

Kaiser, Maria L; Koekemoer, Lizette L; Coetzee, Maureen; Hunt, Richard H; Brooke, Basil D

2010-12-14

mechanisms whose effectiveness may be enhanced by intra-population variation in the expression of resistance phenotypes. The variation in the expression of insecticide resistance in association with selection for larval time-to-hatch may induce this kind of enhanced adaptive plasticity as a consequence of pleiotropy, whereby mosquitoes are able to complete their aquatic life stages in a variable breeding environment using staggered larval time-to-hatch, giving rise to an adult population with enhanced variation in the expression of insecticide resistance.

Postembryonic lineages of the Drosophila ventral nervous system: Neuroglian expression reveals the adult hemilineage associated fiber tracts in the adult thoracic neuromeres

PubMed Central

Harris, Robin; Williams, Darren W.; Truman, James W.

2016-01-01

During larval life most of the thoracic neuroblasts (NBs) in Drosophila undergo a second phase of neurogenesis to generate adult‐specific neurons that remain in an immature, developmentally stalled state until pupation. Using a combination of MARCM and immunostaining with a neurotactin antibody, Truman et al. (2004; Development 131:5167–5184) identified 24 adult‐specific NB lineages within each thoracic hemineuromere of the larval ventral nervous system (VNS), but because of the neurotactin labeling of lineage tracts disappearing early in metamorphosis, they were unable extend the identification of these lineages into the adult. Here we show that immunostaining with an antibody against the cell adhesion molecule neuroglian reveals the same larval secondary lineage projections through metamorphosis and bfy identifying each neuroglian‐positive tract at selected stages we have traced the larval hemilineage tracts for all three thoracic neuromeres through metamorphosis into the adult. To validate tract identifications we used the genetic toolkit developed by Harris et al. (2015; Elife 4) to preserve hemilineage‐specific GAL4 expression patterns from larval into the adult stage. The immortalized expression proved a powerful confirmation of the analysis of the neuroglian scaffold. This work has enabled us to directly link the secondary, larval NB lineages to their adult counterparts. The data provide an anatomical framework that 1) makes it possible to assign most neurons to their parent lineage and 2) allows more precise definitions of the neuronal organization of the adult VNS based in developmental units/rules. J. Comp. Neurol. 524:2677–2695, 2016. © 2016 The Authors The Journal of Comparative Neurology Published by Wiley Periodicals, Inc. PMID:26878258

Exposure to 2,4-decadienal negatively impacts upon marine invertebrate larval fitness.

PubMed

Caldwell, Gary S; Lewis, Ceri; Olive, Peter J W; Bentley, Matthew G

2005-06-01

Diatoms liberate volatile, biologically active unsaturated aldehydes following cell damage, which negatively impact upon invertebrate reproductive processes such as fertilization, embryogenesis and larval survival. 2,4-Decadienal is frequently identified among the aldehydes produced and is one of the more biologically active. The majority of studies which have examined the toxic effects of diatom aldehydes to invertebrate reproduction have scored egg production and/or hatching success as indicators of biological impacts. There are very few studies which have dealt specifically with the impacts of diatom-derived aldehydes on larval fitness. Larval stages of the polychaetes Arenicola marina and Nereis virens and the echinoderms Asterias rubens and Psammechinus miliaris exposed to 2,4-decadienal at sub 1 microg ml(-1) concentrations suffered reduced survival over the incubation period (day 1-8 post fertilization) with detectable differences for the polychates at a concentration of 0.005 and 0.01-0.1 microg ml(-1) for the echinoderms. Susceptibility of larval N. virens was investigated using stage specific 24 h exposures at 2,4-decadienal concentrations up to 1.5 microg ml(-1). A clear stage specific effect was found, with earlier larval stages most vulnerable. Nectochaete larvae (9-10 d) showed no reduction in survival at the concentrations assayed. Fluctuating asymmetry (FA), defined as random deviations from perfect bilateral symmetry, was used to analyse fitness of larval P. miliaris exposed to 2,4-decadienal at concentrations of 0.1, 0.5 and 1 microg ml(-1). The degree and frequency of asymmetrical development increased with increasing 2,4-decadienal concentration. Equally, as FA increased larval survival decreased. These results provide further support for the teratogenic nature of 2,4-decadienal and its negative impact on invertebrate larval fitness.

Larval biology of the crab Rhithropanopeus harrisii (Gould): a synthesis.

PubMed

Forward, Richard B

2009-06-01

This synthesis reviews the physiological ecology and behavior of larvae of the benthic crab Rhithropanopeus harrisii, which occurs in low-salinity areas of estuaries. Larvae are released rhythmically around the time of high tide in tidal estuaries and in the 2-h interval after sunset in nontidal estuaries. As in most subtidal crustaceans, the timing of larval release is controlled by the developing embryos, which release peptide pheromones that stimulate larval release behavior by the female to synchronize the time of egg hatching. Larvae pass through four zoeal stages and a postlarval or megalopal stage that are planktonic before metamorphosis. They are retained near the adult population by means of an endogenous tidal rhythm in vertical migration. Larvae have several safeguards against predation: they undergo nocturnal diel vertical migration (DVM) and have a shadow response to avoid encountering predators, and they bear long spines as a deterrent. Photoresponses during DVM and the shadow response are enhanced by exposure to chemical cues from the mucus of predator fishes and ctenophores. The primary visual pigment has a spectral sensitivity maximum at about 500 nm, which is typical for zooplankton and matches the ambient spectrum at twilight. Larvae can detect vertical gradients in temperature, salinity, and hydrostatic pressure, which are used for depth regulation and avoidance of adverse environmental conditions. Characteristics that are related to the larval habitat and are common to other crab larval species are considered.

Loss of SPARC dysregulates basal lamina assembly to disrupt larval fat body homeostasis in Drosophila melanogaster.

PubMed

Shahab, Jaffer; Baratta, Cristina; Scuric, Bianca; Godt, Dorothea; Venken, Koen J T; Ringuette, Maurice J

2015-04-01

SPARC is a collagen-binding glycoprotein whose functions during early development are unknown. We previously reported that SPARC is expressed in Drosophila by hemocytes and the fat body (FB) and enriched in basal laminae (BL) surrounding tissues, including adipocytes. We sought to explore if SPARC is required for proper BL assembly in the FB. SPARC deficiency leads to larval lethality, associated with remodeling of the FB. In the absence of SPARC, FB polygonal adipocytes assume a spherical morphology. Loss-of-function clonal analyses revealed a cell-autonomous accumulation of BL components around mutant cells that include collagen IV (Col lV), Laminin, and Perlecan. Ultrastructural analyses indicate SPARC-deficient adipocytes are surrounded by an aberrant accumulation of a fibrous extracellular matrix. Our data indicate a critical requirement for SPARC for the proper BL assembly in Drosophila FB. Since Col IV within the BL is a prime determinant of cell shape, the rounded appearance of SPARC-deficient adipocytes is due to aberrant assembly of Col IV. © 2014 Wiley Periodicals, Inc.

Evolution of increased larval competitive ability in Drosophila melanogaster without increased larval feeding rate.

PubMed

Sarangi, Manaswini; Nagarajan, Archana; Dey, Snigdhadip; Bose, Joy; Joshi, Amitabh

2016-09-01

Multiple experimental evolution studies on Drosophila melanogaster in the 1980s and 1990s indicated that enhanced competitive ability evolved primarily through increased larval tolerance to nitrogenous wastes and increased larval feeding and foraging rate, at the cost of efficiency of food conversion to biomass, and this became the widely accepted view of how adaptation to larval crowding evolves in fruitflies.We recently showed that populations of D. ananassae and D. n. nasuta subjected to extreme larval crowding evolved greater competitive ability without evolving higher feeding rates, primarily through a combination of reduced larval duration, faster attainment of minimum critical size for pupation, greater efficiency of food conversion to biomass, increased pupation height and, perhaps, greater urea/ammonia tolerance. This was a very different suite of traits than that seen to evolve under similar selection in D. melanogaster and was closer to the expectations from the theory of K-selection. At that time, we suggested two possible reasons for the differences in the phenotypic correlates of greater competitive ability seen in the studies with D. melanogaster and the other two species. First, that D. ananassae and D. n. nasuta had a very different genetic architecture of traits affecting competitive ability compared to the long-term laboratory populations of D. melanogaster used in the earlier studies, either because the populations of the former two species were relatively recently wild-caught, or by virtue of being different species. Second, that the different evolutionary trajectories in D. ananassae and D. n. nasuta versus D. melanogaster were a reflection of differences in the manner in which larval crowding was imposed in the two sets of selection experiments. The D. melanogaster studies used a higher absolute density of eggs per unit volume of food, and a substantially larger total volume of food, than the studies on D. ananassae and D. n. nasuta. Here, we

Impact of stress, fear and anxiety on the nociceptive responses of larval zebrafish.

PubMed

Lopez-Luna, Javier; Al-Jubouri, Qussay; Al-Nuaimy, Waleed; Sneddon, Lynne U

2017-01-01

Both adult and larval zebrafish have been demonstrated to show behavioural responses to noxious stimulation but also to potentially stress- and fear or anxiety- eliciting situations. The pain or nociceptive response can be altered and modulated by these situations in adult fish through a mechanism called stress-induced analgesia. However, this phenomenon has not been described in larval fish yet. Therefore, this study explores the behavioural changes in larval zebrafish after noxious stimulation and exposure to challenges that can trigger a stress, fear or anxiety reaction. Five-day post fertilization zebrafish were exposed to either a stressor (air emersion), a predatory fear cue (alarm substance) or an anxiogenic (caffeine) alone or prior to immersion in acetic acid 0.1%. Pre- and post-stimulation behaviour (swimming velocity and time spent active) was recorded using a novel tracking software in 25 fish at once. Results show that larvae reduced both velocity and activity after exposure to the air emersion and alarm substance challenges and that these changes were attenuated using etomidate and diazepam, respectively. Exposure to acetic acid decreased velocity and activity as well, whereas air emersion and alarm substance inhibited these responses, showing no differences between pre- and post-stimulation. Therefore, we hypothesize that an antinociceptive mechanism, activated by stress and/or fear, occur in 5dpf zebrafish, which could have prevented the larvae to display the characteristic responses to pain.

Reactivation of larval keratin gene (krt62.L) in blastema epithelium during Xenopus froglet limb regeneration.

PubMed

Satoh, Akira; Mitogawa, Kazumasa; Saito, Nanami; Suzuki, Miyuki; Suzuki, Ken-Ichi T; Ochi, Haruki; Makanae, Aki

2017-12-15

Limb regeneration is considered a form of limb redevelopment because of the molecular and morphological similarities. Forming a regeneration blastema is, in essence, creating a developing limb bud in an adult body. This reactivation of a developmental process in a mature body is worth studying. Xenopus laevis has a biphasic life cycle that involves distinct larval and adult stages. These distinct developmental stages are useful for investigating the reactivation of developmental processes in post-metamorphic frogs (froglets). In this study, we focused on the re-expression of a larval gene (krt62.L) during Xenopus froglet limb regeneration. Recently renamed krt62.L, this gene was known as the larval keratin (xlk) gene, which is specific to larval-tadpole stages. During limb regeneration in a froglet, krt62.L was re-expressed in a basal layer of blastema epithelium, where adult-specific keratin (Krt12.6.S) expression was also observable. Nerves produce important regulatory factors for amphibian limb regeneration, and also play a role in blastema formation and maintenance. The effect of nerve function on krt62.L expression could be seen in the maintenance of krt62.L expression, but not in its induction. When an epidermis-stripped limb bud was grafted in a froglet blastema, the grafted limb bud could reach the digit-forming stage. This suggests that krt62.L-positive froglet blastema epithelium is able to support the limb development process. These findings imply that the developmental process is locally reactivated in an postmetamorphic body during limb regeneration. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

Alcohol, Intestinal Bacterial Growth, Intestinal Permeability to Endotoxin, and Medical Consequences

PubMed Central

Purohit, Vishnudutt; Bode, J. Christian; Bode, Christiane; Brenner, David A.; Choudhry, Mashkoor A.; Hamilton, Frank; Kang, Y. James; Keshavarzian, Ali; Rao, Radhakrishna; Sartor, R. Balfour; Swanson, Christine; Turner, Jerrold R.

2008-01-01

This report is a summary of the symposium on Alcohol, Intestinal Bacterial Growth, Intestinal Permeability to Endotoxin, and Medical Consequences, organized by National Institute on Alcohol Abuse and Alcoholism, Office of Dietary Supplements, and National Institute of Diabetes and Digestive and Kidney Diseases of National Institutes of Health in Rockville, Maryland, October 11, 2006. Alcohol exposure can promote the growth of Gram negative bacteria in the intestine which may result in accumulation of endotoxin. In addition, alcohol metabolism by Gram negative bacteria and intestinal epithelial cells can result in accumulation of acetaldehyde, which in turn can increase intestinal permeability to endotoxin by increasing tyrosine phosphorylation of tight junction and adherens junction proteins. Alcohol-induced generation of nitric oxide may also contribute to increased permeability to endotoxin by reacting with tubulin, which may cause damage to microtubule cytoskeleton and subsequent disruption of intestinal barrier function. Increased intestinal permeability can lead to increased transfer of endotoxin from the intestine to the liver and general circulation where endotoxin may trigger inflammatory changes in the liver and other organs. Alcohol may also increase intestinal permeability to peptidoglycan which can initiate inflammatory response in liver and other organs. In addition, acute alcohol exposure may potentiate the effect of burn injury on intestinal bacterial growth and permeability. Decreasing the number of Gram negative bacteria in the intestine can result in decreased production of endotoxin as well as acetaldehyde which is expected to decrease intestinal permeability to endotoxin. In addition, intestinal permeability may be preserved by administering epidermal growth factor, L-glutamine, oats supplementation, or zinc thereby preventing the transfer of endotoxin to the general circulation. Thus reducing the number of intestinal Gram negative bacteria and

Antibacterial activity inducible in the haemolymph of the silkworm, Bombyx mori, by injection of formalin-treated Escherichia coli K-12 during the fifth larval instar and pharate adult development.

PubMed

Sumida, M; Ichimori, H; Johchi, S; Takaoka, A; Yuhki, T; Mori, H; Matsubara, F

1992-01-01

1. Antibacterial activity inducible in the haemolymph of the silkworm, Bombyx mori, by immunization, i.e. by injection of formalin-treated Escherichia coli (E. coli) K-12 during the fifth larval instar and pharate adult development that was reared aseptically on an artificial diet was determined by inhibition zone assay using the same bacterium as a test organism. 2. A peak of antibacterial activity was observed in each development stage; approximately 8 mm in diameter of a clear zone at days 3 or 4 in the fifth larval instar and approximately 5 mm at day 1 in the pharate adults. 3. Acid polyacrylamide gel electrophoresis of immunized haemolymph followed by overlay assay showed that an activity band was associated with two peptide bands that were similar to the cecropin-like peptides A and B that were reported in the silkworm (Morishima et al., 1988, Agri. Biol. Chem. 52, 929-934). Any other activity bands were not observed. No activity band was detectable from the haemolymph of non-immunized insects. 4. Fractionation of antibacterial peptides in immunized haemolymph on a CM-cellulose column resulted in separation of two groups of activity, both in the fifth instar larvae and in the pharate adults with a slight difference in elution conditions. 5. Duration of high antibacterial activity induced by a single immunization was approximately 12 hr in the fifth instar day 3 larvae and 48 hr in the day 2 pharate adults.

[Intestinal volvulus. Case report and a literature review].

PubMed

Santín-Rivero, Jorge; Núñez-García, Edgar; Aguirre-García, Manuel; Hagerman-Ruiz-Galindo, Gonzalo; de la Vega-González, Francisco; Moctezuma-Velasco, Carla Rubi

2015-01-01

Small bowel volvulus is a rare cause of intestinal obstruction in adult patients. This disease is more common in children and its aetiology and management is different to that in adults. A 30 year-old male with sarcoidosis presents with acute abdomen and clinical data of intestinal obstruction. Small bowel volvulus is diagnosed by a contrast abdominal tomography and an exploratory laparotomy is performed with devolvulation and no intestinal resection. In the days following surgery, he developed a recurrent small bowel volvulus, which was again managed with surgery, but without intestinal resection. Medical treatment for sarcoidosis was started, and with his clinical progress being satisfactory,he was discharged to home. Making an early and correct diagnosis of small bowel volvulus prevents large intestinal resections. Many surgical procedures have been described with a high rate of complications. Therefore, conservative surgical management (no intestinal resection) is recommended as the best treatment with the lowest morbidity and mortality rate. Copyright © 2015 Academia Mexicana de Cirugía A.C. Published by Masson Doyma México S.A. All rights reserved.

Anticipatory flexibility: larval population density in moths determines male investment in antennae, wings and testes.

PubMed

Johnson, Tamara L; Symonds, Matthew R E; Elgar, Mark A

2017-11-15

Developmental plasticity provides individuals with a distinct advantage when the reproductive environment changes dramatically. Variation in population density, in particular, can have profound effects on male reproductive success. Females may be easier to locate in dense populations, but there may be a greater risk of sperm competition. Thus, males should invest in traits that enhance fertilization success over traits that enhance mate location. Conversely, males in less dense populations should invest more in structures that will facilitate mate location. In Lepidoptera, this may result in the development of larger antennae to increase the likelihood of detecting female sex pheromones, and larger wings to fly more efficiently. We explored the effects of larval density on adult morphology in the gum-leaf skeletonizer moth, Uraba lugens , by manipulating both the number of larvae and the size of the rearing container. This experimental arrangement allowed us to reveal the cues used by larvae to assess whether absolute number or density influences adult responses. Male investment in testes size depended on the number of individuals, while male investment in wings and antennae depended upon larval density. By contrast, the size of female antennae and wings were influenced by an interaction of larval number and container size. This study demonstrates that male larvae are sensitive to cues that may reveal adult population density, and adjust investment in traits associated with fertilization success and mate detection accordingly. © 2017 The Author(s).

Volvulus of the Small Intestine in Adults

PubMed Central

Talbot, C. H.

1960-01-01

Five cases of volvulus of varying lengths of the small intestine are described. The incidence and the aetiology of the condition are briefly discussed. Shock as a feature of extensive volvulus is stressed, and its cause in these cases is related to the previous animal experimental work of others. The other clinical features are briefly described. In the management of these cases the urgency for laparotomy is stressed and immediate delivery from the abdomen of the whole small bowel is advocated. Reference is made to the literature of massive resection of the small intestine to illustrate that the prognosis is not necessarily poor when resections are extensive. PMID:13836720

Intestinal Pseudo-Obstruction

MedlinePlus

... condition as adults. Intestinal pseudo-obstruction may be acute, occurring suddenly and lasting a short time, or it may be chronic, or long lasting. Acute colonic pseudo-obstruction, also called Ogilvie syndrome or ...

Energy Efficiency Measures to Incorporate into Remodeling Projects

DOE Office of Scientific and Technical Information (OSTI.GOV)

Liaukus, C.

2014-12-01

Energy improvements in a home are often approached as one concerted effort, beginning with a simple walk-through assessment or more in-depth energy audit and followed by the installation of recommended energy measures. While this approach allows for systems thinking to guide the efforts, comprehensive energy improvements of this nature are undertaken by a relatively small number of U.S. households compared to piecemeal remodeling efforts. In this report, the U.S Department of Energy Building America Retrofit Alliance research team examines the improvement of a home’s energy performance in an opportunistic way by examining what can be done to incorporate energy efficiencymore » measures into general remodeling work and home repair projects. This allows for energy efficiency upgrades to occur at the same time as remodeling proejcts. There are challenges to this approach, not the least of which being that the work will take place over time in potentially many separate projects. The opportunity to improve a home’s energy efficiency at one time expands or contracts with the scope of the remodel. As such, guidance on how to do each piece thoughtfully and with consideration for potential future projects, is critical.« less

On the morphology of the central nervous system in larval stages of Carcinus maenas L. (Decapoda, Brachyura)

NASA Astrophysics Data System (ADS)

Harzsch, S.; Dawirs, R. R.

1993-02-01

We investigated the morphology of the central nervous system throughout the larval development of Carcinus maenas. For that purpose single larvae were reared in the laboratory from hatching through metamorphosis. Complete series of whole mout semithin sections were obtained from individuals of all successive larval stages and analysed with a light microscope. Morphological feature and spatial arrangement of discernable neural cell clusters, fibre tracts and neuropile are described and compared with the adult pattern. We found that most of the morphological features characterizing the adult nervous system are already present in the zoea-1. Nevertheless, there are marked differences with respect to the arrangement of nerve cell bodies, organization of cerebral neuropile, and disposition of ganglia in the ventral nerve cord. It appears that complexity of the central nervous neuropile is selectively altered during postmetamorphotic development, probably reflecting adaptive changes of sensory-motor integration in response to behavioural maturation. In contrast, during larval development there was little change in the overall structural organization of the central nervous system despite some considerable growth. However, the transition from zoea-4 to megalopa brings about multiple fundamental changes in larval morphology and behavioural pattern. Since central nervous integration should properly adapt to the altered behavioural repertoire of the megalopa, it seems necessary to ask in which respect synaptic rearrangement might characterize development of the central nervous system.

Tissue damage-induced intestinal stem cell division in Drosophila

PubMed Central

Amcheslavsky, Alla; Jiang, Jin; Ip, Y. Tony

2009-01-01

SUMMARY Stem cell division is essential for tissue integrity during growth, aging, and pathogenic assaults. Adult gastrointestinal tract encounters numerous stimulations and impaired tissue regeneration may lead to inflammatory diseases and cancer. Intestinal stem cells in adult Drosophila have recently been identified and shown to replenish the various cell types within the midgut. However, it is not known whether these intestinal stem cells can respond to environmental challenges. By feeding dextran sulfate sodium and bleomycin to flies and by expressing apoptotic proteins, we show that Drosophila intestinal stem cells can increase the rate of division in response to tissue damage. Moreover, if tissue damage results in epithelial cell loss, the newly formed enteroblasts can differentiate into mature epithelial cells. By using this newly established system of intestinal stem cell proliferation and tissue regeneration, we find that the insulin receptor signaling pathway is required for intestinal stem cell division. PMID:19128792

Penetration of the small intestine of a California sea lion (Zalophus californianus) pup by adult hookworms (Uncinaria spp).

PubMed

Spraker, T R; Lyons, E T; DeLong, R L; Zink, R R

2004-03-01

During a study on the mortality of California sea lion (Zalophus californianus) pups born on San Miguel Island, California in 2002, two adult female hookworms (Uncinaria spp) were found penetrating the serosal surface of the intestinal wall and protruding into the peritoneal cavity of one pup. Documentation and a description of this unexpected finding and associated lesions are presented here. Also, adult hookworms were found in the peritoneal fluid of two other dead Z. californianus pups.

Biochemical Characterization and Vaccine Potential of a Heme-Binding Glutathione Transferase from the Adult Hookworm Ancylostoma caninum

PubMed Central

Zhan, Bin; Liu, Sen; Perally, Samirah; Xue, Jian; Fujiwara, Ricardo; Brophy, Peter; Xiao, Shuhua; Liu, Yueyuan; Feng, Jianjun; Williamson, Angela; Wang, Yan; Bueno, Lilian L.; Mendez, Susana; Goud, Gaddam; Bethony, Jeffrey M.; Hawdon, John M.; Loukas, Alex; Jones, Karen; Hotez, Peter J.

2005-01-01

We report the cloning and expression of Ac-GST-1, a novel glutathione S-transferase from the adult hookworm Ancylostoma caninum, and its possible role in parasite blood feeding and as a vaccine target. The predicted Ac-GST-1 open reading frame contains 207 amino acids (mass, 24 kDa) and exhibited up to 65% amino acid identity with other nematode GSTs. mRNA encoding Ac-GST-1 was detected in adults, eggs, and larval stages, but the protein was detected only in adult hookworm somatic extracts and excretory/secretory products. Using antiserum to the recombinant protein, Ac-GST-1 was immunolocalized to the parasite hypodermis and muscle tissue and weakly to the intestine. Recombinant Ac-GST-1 was enzymatically active, as determined by conjugation of glutathione to a model substrate, and exhibited a novel high-affinity binding site for hematin. The possible role of Ac-GST-1 in parasite heme detoxification during hemoglobin digestion or heme uptake prompted interest in evaluating it as a potential vaccine antigen. Vaccination of dogs with Ac-GST-1 resulted in a 39.4% reduction in the mean worm burden and 32.3% reduction in egg counts compared to control dogs following larval challenge, although the reductions were not statistically significant. However, hamsters vaccinated with Ac-GST-1 exhibited statistically significant worm reduction (53.7%) following challenge with heterologous Necator americanus larvae. These studies suggest that Ac-GST-1 is a possible drug and vaccine target for hookworm infection. PMID:16177370

Phylogenetic analyses of mode of larval development.

PubMed

Hart, M

2000-12-01

Phylogenies based on morphological or molecular characters have been used to provide an evolutionary context for analysis of larval evolution. Studies of gastropods, bivalves, tunicates, sea stars, sea urchins, and polychaetes have revealed massive parallel evolution of similar larval forms. Some of these studies were designed to test, and have rejected, the species selection hypothesis for evolutionary trends in the frequency of derived larvae or life history traits. However, the lack of well supported models of larval character evolution leave some doubt about the quality of inferences of larval evolution from phylogenies of living taxa. Better models based on maximum likelihood methods and known prior probabilities of larval character state changes will improve our understanding of the history of larval evolution. Copyright 2000 Academic Press.

Adaptive scapula bone remodeling computational simulation: Relevance to regenerative medicine

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sharma, Gulshan B., E-mail: gbsharma@ucalgary.ca; University of Pittsburgh, Swanson School of Engineering, Department of Bioengineering, Pittsburgh, Pennsylvania 15213; University of Calgary, Schulich School of Engineering, Department of Mechanical and Manufacturing Engineering, Calgary, Alberta T2N 1N4

Shoulder arthroplasty success has been attributed to many factors including, bone quality, soft tissue balancing, surgeon experience, and implant design. Improved long-term success is primarily limited by glenoid implant loosening. Prosthesis design examines materials and shape and determines whether the design should withstand a lifetime of use. Finite element (FE) analyses have been extensively used to study stresses and strains produced in implants and bone. However, these static analyses only measure a moment in time and not the adaptive response to the altered environment produced by the therapeutic intervention. Computational analyses that integrate remodeling rules predict how bone will respondmore » over time. Recent work has shown that subject-specific two- and three dimensional adaptive bone remodeling models are feasible and valid. Feasibility and validation were achieved computationally, simulating bone remodeling using an intact human scapula, initially resetting the scapular bone material properties to be uniform, numerically simulating sequential loading, and comparing the bone remodeling simulation results to the actual scapula’s material properties. Three-dimensional scapula FE bone model was created using volumetric computed tomography images. Muscle and joint load and boundary conditions were applied based on values reported in the literature. Internal bone remodeling was based on element strain-energy density. Initially, all bone elements were assigned a homogeneous density. All loads were applied for 10 iterations. After every iteration, each bone element’s remodeling stimulus was compared to its corresponding reference stimulus and its material properties modified. The simulation achieved convergence. At the end of the simulation the predicted and actual specimen bone apparent density were plotted and compared. Location of high and low predicted bone density was comparable to the actual specimen. High predicted bone density was greater

Adaptive scapula bone remodeling computational simulation: Relevance to regenerative medicine

NASA Astrophysics Data System (ADS)

Sharma, Gulshan B.; Robertson, Douglas D.

2013-07-01

Shoulder arthroplasty success has been attributed to many factors including, bone quality, soft tissue balancing, surgeon experience, and implant design. Improved long-term success is primarily limited by glenoid implant loosening. Prosthesis design examines materials and shape and determines whether the design should withstand a lifetime of use. Finite element (FE) analyses have been extensively used to study stresses and strains produced in implants and bone. However, these static analyses only measure a moment in time and not the adaptive response to the altered environment produced by the therapeutic intervention. Computational analyses that integrate remodeling rules predict how bone will respond over time. Recent work has shown that subject-specific two- and three dimensional adaptive bone remodeling models are feasible and valid. Feasibility and validation were achieved computationally, simulating bone remodeling using an intact human scapula, initially resetting the scapular bone material properties to be uniform, numerically simulating sequential loading, and comparing the bone remodeling simulation results to the actual scapula's material properties. Three-dimensional scapula FE bone model was created using volumetric computed tomography images. Muscle and joint load and boundary conditions were applied based on values reported in the literature. Internal bone remodeling was based on element strain-energy density. Initially, all bone elements were assigned a homogeneous density. All loads were applied for 10 iterations. After every iteration, each bone element's remodeling stimulus was compared to its corresponding reference stimulus and its material properties modified. The simulation achieved convergence. At the end of the simulation the predicted and actual specimen bone apparent density were plotted and compared. Location of high and low predicted bone density was comparable to the actual specimen. High predicted bone density was greater than actual

The Him gene inhibits the development of Drosophila flight muscles during metamorphosis.

PubMed

Soler, Cédric; Taylor, Michael V

2009-07-01

During Drosophila metamorphosis some larval tissues escape the general histolysis and are remodelled to form adult tissues. One example is the dorso-longitudinal muscles (DLMs) of the indirect flight musculature. They are formed by an intriguing process in which residual larval oblique muscles (LOMs) split and fuse with imaginal myoblasts associated with the wing disc. These myoblasts arise in the embryo, but remain undifferentiated throughout embryogenesis and larval life, and thus share characteristics with mammalian satellite cells. However, the mechanisms that maintain the Drosophila myoblasts in an undifferentiated state until needed for LOM remodelling are not understood. Here we show that the Him gene is expressed in these myoblasts, but is undetectable in developing DLM fibres. Consistent with this, we found that Him could inhibit DLM development: it inhibited LOM splitting and resulted in fibre degeneration. We then uncovered a balance between mef2, a positive factor required for proper DLM development, and the inhibitory action of Him. Mef2 suppressed the inhibitory effect of Him on DLM development, while Him could suppress the premature myosin expression induced by mef2 in myoblasts. Furthermore, either decreased Him function or increased mef2 function disrupted DLM development. These findings, together with the co-expression of Him and Mef2 in myoblasts, indicate that Him may antagonise mef2 function during normal DLM development and that Him participates in a balance of signals that controls adult myoblast differentiation and remodelling of these muscle fibres. Lastly, we provide evidence for a link between Notch function and Him and mef2 in this balance.

Larval crowding accelerates C. elegans development and reduces lifespan.

PubMed

Ludewig, Andreas H; Gimond, Clotilde; Judkins, Joshua C; Thornton, Staci; Pulido, Dania C; Micikas, Robert J; Döring, Frank; Antebi, Adam; Braendle, Christian; Schroeder, Frank C

2017-04-01

Environmental conditions experienced during animal development are thought to have sustained impact on maturation and adult lifespan. Here we show that in the model organism C. elegans developmental rate and adult lifespan depend on larval population density, and that this effect is mediated by excreted small molecules. By using the time point of first egg laying as a marker for full maturity, we found that wildtype hermaphrodites raised under high density conditions developed significantly faster than animals raised in isolation. Population density-dependent acceleration of development (Pdda) was dramatically enhanced in fatty acid β-oxidation mutants that are defective in the biosynthesis of ascarosides, small-molecule signals that induce developmental diapause. In contrast, Pdda is abolished by synthetic ascarosides and steroidal ligands of the nuclear hormone receptor DAF-12. We show that neither ascarosides nor any known steroid hormones are required for Pdda and that another chemical signal mediates this phenotype, in part via the nuclear hormone receptor NHR-8. Our results demonstrate that C. elegans development is regulated by a push-pull mechanism, based on two antagonistic chemical signals: chemosensation of ascarosides slows down development, whereas population-density dependent accumulation of a different chemical signal accelerates development. We further show that the effects of high larval population density persist through adulthood, as C. elegans larvae raised at high densities exhibit significantly reduced adult lifespan and respond differently to exogenous chemical signals compared to larvae raised at low densities, independent of density during adulthood. Our results demonstrate how inter-organismal signaling during development regulates reproductive maturation and longevity.

Larval crowding accelerates C. elegans development and reduces lifespan

PubMed Central

Ludewig, Andreas H.; Gimond, Clotilde; Judkins, Joshua C.; Thornton, Staci; Pulido, Dania C.; Micikas, Robert J.; Döring, Frank; Antebi, Adam; Braendle, Christian; Schroeder, Frank C.

2017-01-01

Environmental conditions experienced during animal development are thought to have sustained impact on maturation and adult lifespan. Here we show that in the model organism C. elegans developmental rate and adult lifespan depend on larval population density, and that this effect is mediated by excreted small molecules. By using the time point of first egg laying as a marker for full maturity, we found that wildtype hermaphrodites raised under high density conditions developed significantly faster than animals raised in isolation. Population density-dependent acceleration of development (Pdda) was dramatically enhanced in fatty acid β-oxidation mutants that are defective in the biosynthesis of ascarosides, small-molecule signals that induce developmental diapause. In contrast, Pdda is abolished by synthetic ascarosides and steroidal ligands of the nuclear hormone receptor DAF-12. We show that neither ascarosides nor any known steroid hormones are required for Pdda and that another chemical signal mediates this phenotype, in part via the nuclear hormone receptor NHR-8. Our results demonstrate that C. elegans development is regulated by a push-pull mechanism, based on two antagonistic chemical signals: chemosensation of ascarosides slows down development, whereas population-density dependent accumulation of a different chemical signal accelerates development. We further show that the effects of high larval population density persist through adulthood, as C. elegans larvae raised at high densities exhibit significantly reduced adult lifespan and respond differently to exogenous chemical signals compared to larvae raised at low densities, independent of density during adulthood. Our results demonstrate how inter-organismal signaling during development regulates reproductive maturation and longevity. PMID:28394895

Larval dispersal in three coral reef decapod species: Influence of larval duration on the metapopulation structure.

PubMed

Sanvicente-Añorve, Laura; Zavala-Hidalgo, Jorge; Allende-Arandía, Eugenia; Hermoso-Salazar, Margarita

2018-01-01

Most coral-associated decapod species have non-migratory adult populations and depend on their planktonic larvae for dispersal. This study examined the metapopulation structure of three decapod species with different pelagic larval duration (PLD) from twelve coral reef complexes of the Gulf of Mexico. The dispersion of larvae was analyzed through the use of a realistic numerical simulation of the Gulf of Mexico with the Hybrid Coordinate Ocean Model. To study the transport and dispersion of particles in near-surface waters, a particle-tracking subroutine was run using as input the currents from the model. The simulation consisted of the launch of 100 passive particles (virtual larvae) every 24 hours from each reef throughout five years, and tracked for as long as 210 days. Results indicated that species with a short PLD, Mithraculus sculptus (PLD 8‒13 days), had a weak connection among the reefs, but higher self-recruitment, especially on the narrow western shelf. The species with a longer PLD, Dromia erythropus (28‒30 days), had a stronger connection among neighboring reefs (< 300 km). Finally, the species with an even longer PLD, Stenopus hispidus (123‒210 days), had a wider potential distribution than the other species. Circulation on synoptic, seasonal and interannual scales had differential effects on the larval dispersal of each species. The metapopulation structure of M. sculptus and D. erythropus seemed to combine features of the non-equilibrium and the patchy models, whereas that of S. hispidus presumably fit to a patchy model. These findings support previous observations that indicate that species with longer PLD tend to occupy larger areas than species with short PLD, although recruitment of juveniles to the adult populations will also depend on other factors, such as the availability of suitable habitats and the ability to colonize them.

Larval dispersal in three coral reef decapod species: Influence of larval duration on the metapopulation structure

PubMed Central

Zavala-Hidalgo, Jorge; Allende-Arandía, Eugenia; Hermoso-Salazar, Margarita

2018-01-01

Most coral-associated decapod species have non-migratory adult populations and depend on their planktonic larvae for dispersal. This study examined the metapopulation structure of three decapod species with different pelagic larval duration (PLD) from twelve coral reef complexes of the Gulf of Mexico. The dispersion of larvae was analyzed through the use of a realistic numerical simulation of the Gulf of Mexico with the Hybrid Coordinate Ocean Model. To study the transport and dispersion of particles in near-surface waters, a particle-tracking subroutine was run using as input the currents from the model. The simulation consisted of the launch of 100 passive particles (virtual larvae) every 24 hours from each reef throughout five years, and tracked for as long as 210 days. Results indicated that species with a short PLD, Mithraculus sculptus (PLD 8‒13 days), had a weak connection among the reefs, but higher self-recruitment, especially on the narrow western shelf. The species with a longer PLD, Dromia erythropus (28‒30 days), had a stronger connection among neighboring reefs (< 300 km). Finally, the species with an even longer PLD, Stenopus hispidus (123‒210 days), had a wider potential distribution than the other species. Circulation on synoptic, seasonal and interannual scales had differential effects on the larval dispersal of each species. The metapopulation structure of M. sculptus and D. erythropus seemed to combine features of the non-equilibrium and the patchy models, whereas that of S. hispidus presumably fit to a patchy model. These findings support previous observations that indicate that species with longer PLD tend to occupy larger areas than species with short PLD, although recruitment of juveniles to the adult populations will also depend on other factors, such as the availability of suitable habitats and the ability to colonize them. PMID:29558478

No-Regrets Remodeling, 2nd Edition

DOE Office of Scientific and Technical Information (OSTI.GOV)

None

2013-12-01

No-Regrets Remodeling, sponsored by Oak Ridge National Laboratory, is an informative publication that walks homeowners and/or remodelers through various home remodeling projects. In addition to remodeling information, the publication provides instruction on how to incorporate energy efficiency into the remodeling process. The goal of the publication is to improve homeowner satisfaction after completing a remodeling project and to provide the homeowner with a home that saves energy and is comfortable and healthy.

[Intestinal lymphangiectasis secondary to cicatricial fibrosis of mesenteric nodes: a nosologic entity?].

PubMed

Molas, G; Ponsot, P; Amouyal, P; Vallin, J; Vitaux, J; Paolaggi, J A; Potet, F

1990-01-01

Exsudative enteropathy was suspected in a 27-year-old man with lower limb edema, hypoprotidemia and hypoalbuminemia. Gastrointestinal mucosa, kidney, liver, and heart were normal. Laparoscopy showed diffuse small intestine lymphangiectasia. This diagnosis was confirmed by the microscopic examination of several biopsies obtained at laparotomy. Pathological examination of peritoneal, lymph nodes, and liver biopsies showed fibrous thickening of the peritoneum and fibrosis of the lymph nodes. Our patient has been followed for 16 years. Substantial improvement of clinical symptoms was obtained by following a special salt-free diet containing short-chain triglycerides. However biochemical abnormalities have persisted. Exsudative enteropathy due to intestinal lymphangiectasia may be observed in heart and liver diseases as well as in malignant affections of mesenteric lymph nodes. If these conditions are excluded, intestinal lymphangiectasia may be considered as a primitive lymph vessel malformation. The discovery of primitive intestinal lymphangiectasia in an adult cannot be attributed to congenital abnormalities alone. Fibrosis encountered in some cases suggests that an inflammatory process of unknown origin may trigger the onset of intestinal lymphangiectasia.

Drosophila Activin- and the Activin-like product Dawdle function redundantly to regulate proliferation in the larval brain.

PubMed

Zhu, Changqi C; Boone, Jason Q; Jensen, Philip A; Hanna, Scott; Podemski, Lynn; Locke, John; Doe, Chris Q; O'Connor, Michael B

2008-02-01

The Drosophila Activin-like ligands Activin-beta and Dawdle control several aspects of neuronal morphogenesis, including mushroom body remodeling, dorsal neuron morphogenesis and motoneuron axon guidance. Here we show that the same two ligands act redundantly through the Activin receptor Babo and its transcriptional mediator Smad2 (Smox), to regulate neuroblast numbers and proliferation rates in the developing larval brain. Blocking this pathway results in the development of larvae with small brains and aberrant photoreceptor axon targeting, and restoring babo function in neuroblasts rescued these mutant phenotypes. These results suggest that the Activin signaling pathway is required for producing the proper number of neurons to enable normal connection of incoming photoreceptor axons to their targets. Furthermore, as the Activin pathway plays a key role in regulating propagation of mouse and human embryonic stem cells, our observation that it also regulates neuroblast numbers and proliferation in Drosophila suggests that involvement of Activins in controlling stem cell propagation may be a common regulatory feature of this family of TGF-beta-type ligands.

Comparative Transcriptomic Analysis Reveals Candidate Genes and Pathways Involved in Larval Settlement of the Barnacle Megabalanus volcano.

PubMed

Yan, Guoyong; Zhang, Gen; Huang, Jiaomei; Lan, Yi; Sun, Jin; Zeng, Cong; Wang, Yong; Qian, Pei-Yuan; He, Lisheng

2017-10-27

Megabalanus barnacle is one of the model organisms for marine biofouling research. However, further elucidation of molecular mechanisms underlying larval settlement has been hindered due to the lack of genomic information thus far. In the present study, cDNA libraries were constructed for cyprids, the key stage for larval settlement, and adults of Megabalanus volcano . After high-throughput sequencing and de novo assembly, 42,620 unigenes were obtained with a N50 value of 1532 bp. These unigenes were annotated by blasting against the NCBI non-redundant (nr), Swiss-Prot, Cluster of Orthologous Groups (COG), and Kyoto Encyclopedia of Genes and Genomes (KEGG) databases. Finally, 19,522, 15,691, 14,459, and 10,914 unigenes were identified correspondingly. There were 22,158 differentially expressed genes (DEGs) identified between two stages. Compared with the cyprid stage, 8241 unigenes were down-regulated and 13,917 unigenes were up-regulated at the adult stage. The neuroactive ligand-receptor interaction pathway (ko04080) was significantly enriched by KEGG enrichment analysis of the DEGs, suggesting that it possibly involved in larval settlement. Potential functions of three conserved allatostatin neuropeptide-receptor pairs and two light-sensitive opsin proteins were further characterized, indicating that they might regulate attachment and metamorphosis at cyprid stage. These results provided a deeper insight into the molecular mechanisms underlying larval settlement of barnacles.

Comparative Transcriptomic Analysis Reveals Candidate Genes and Pathways Involved in Larval Settlement of the Barnacle Megabalanus volcano

PubMed Central

Yan, Guoyong; Huang, Jiaomei; Lan, Yi; Zeng, Cong; Wang, Yong; Qian, Pei-Yuan; He, Lisheng

2017-01-01

Megabalanus barnacle is one of the model organisms for marine biofouling research. However, further elucidation of molecular mechanisms underlying larval settlement has been hindered due to the lack of genomic information thus far. In the present study, cDNA libraries were constructed for cyprids, the key stage for larval settlement, and adults of Megabalanus volcano. After high-throughput sequencing and de novo assembly, 42,620 unigenes were obtained with a N50 value of 1532 bp. These unigenes were annotated by blasting against the NCBI non-redundant (nr), Swiss-Prot, Cluster of Orthologous Groups (COG), and Kyoto Encyclopedia of Genes and Genomes (KEGG) databases. Finally, 19,522, 15,691, 14,459, and 10,914 unigenes were identified correspondingly. There were 22,158 differentially expressed genes (DEGs) identified between two stages. Compared with the cyprid stage, 8241 unigenes were down-regulated and 13,917 unigenes were up-regulated at the adult stage. The neuroactive ligand-receptor interaction pathway (ko04080) was significantly enriched by KEGG enrichment analysis of the DEGs, suggesting that it possibly involved in larval settlement. Potential functions of three conserved allatostatin neuropeptide-receptor pairs and two light-sensitive opsin proteins were further characterized, indicating that they might regulate attachment and metamorphosis at cyprid stage. These results provided a deeper insight into the molecular mechanisms underlying larval settlement of barnacles. PMID:29077039

A liquid larval diet for rearing Bactrocera invadens and Ceratitis fasciventris (Diptera:Tephritidae)

USDA-ARS?s Scientific Manuscript database

Bactrocera invadens Drew, Tsuruta & White and Ceratitis fasciventris (Bezzi) are the major fruit fly pests of fruits and vegetables in Africa. The effects of two types of larval diet, liquid and solid (carrot based), on various quality control parameters (pupal recovery, pupal weight, adult emergenc...

Protein kinetic signatures of the remodeling heart following isoproterenol stimulation.

PubMed

Lam, Maggie P Y; Wang, Ding; Lau, Edward; Liem, David A; Kim, Allen K; Ng, Dominic C M; Liang, Xiangbo; Bleakley, Brian J; Liu, Chenguang; Tabaraki, Jason D; Cadeiras, Martin; Wang, Yibin; Deng, Mario C; Ping, Peipei

2014-04-01

Protein temporal dynamics play a critical role in time-dimensional pathophysiological processes, including the gradual cardiac remodeling that occurs in early-stage heart failure. Methods for quantitative assessments of protein kinetics are lacking, and despite knowledge gained from single-protein studies, integrative views of the coordinated behavior of multiple proteins in cardiac remodeling are scarce. Here, we developed a workflow that integrates deuterium oxide (2H2O) labeling, high-resolution mass spectrometry (MS), and custom computational methods to systematically interrogate in vivo protein turnover. Using this workflow, we characterized the in vivo turnover kinetics of 2,964 proteins in a mouse model of β-adrenergic-induced cardiac remodeling. The data provided a quantitative and longitudinal view of cardiac remodeling at the molecular level, revealing widespread kinetic regulations in calcium signaling, metabolism, proteostasis, and mitochondrial dynamics. We translated the workflow to human studies, creating a reference dataset of 496 plasma protein turnover rates from 4 healthy adults. The approach is applicable to short, minimal label enrichment and can be performed on as little as a single biopsy, thereby overcoming critical obstacles to clinical investigations. The protein turnover quantitation experiments and computational workflow described here should be widely applicable to large-scale biomolecular investigations of human disease mechanisms with a temporal perspective.

Protein kinetic signatures of the remodeling heart following isoproterenol stimulation

PubMed Central

Lam, Maggie P.Y.; Wang, Ding; Lau, Edward; Liem, David A.; Kim, Allen K.; Ng, Dominic C.M.; Liang, Xiangbo; Bleakley, Brian J.; Liu, Chenguang; Tabaraki, Jason D.; Cadeiras, Martin; Wang, Yibin; Deng, Mario C.; Ping, Peipei

2014-01-01

Protein temporal dynamics play a critical role in time-dimensional pathophysiological processes, including the gradual cardiac remodeling that occurs in early-stage heart failure. Methods for quantitative assessments of protein kinetics are lacking, and despite knowledge gained from single-protein studies, integrative views of the coordinated behavior of multiple proteins in cardiac remodeling are scarce. Here, we developed a workflow that integrates deuterium oxide (2H2O) labeling, high-resolution mass spectrometry (MS), and custom computational methods to systematically interrogate in vivo protein turnover. Using this workflow, we characterized the in vivo turnover kinetics of 2,964 proteins in a mouse model of β-adrenergic–induced cardiac remodeling. The data provided a quantitative and longitudinal view of cardiac remodeling at the molecular level, revealing widespread kinetic regulations in calcium signaling, metabolism, proteostasis, and mitochondrial dynamics. We translated the workflow to human studies, creating a reference dataset of 496 plasma protein turnover rates from 4 healthy adults. The approach is applicable to short, minimal label enrichment and can be performed on as little as a single biopsy, thereby overcoming critical obstacles to clinical investigations. The protein turnover quantitation experiments and computational workflow described here should be widely applicable to large-scale biomolecular investigations of human disease mechanisms with a temporal perspective. PMID:24614109

REMODELING SENSORY CORTICAL MAPS IMPLANTS SPECIFIC BEHAVIORAL MEMORY

PubMed Central

Bieszczad, Kasia M.; Miasnikov, Alexandre A.; Weinberger, Norman M.

2013-01-01

Neural mechanisms underlying the capacity of memory to be rich with sensory detail are largely unknown. A candidate mechanism is learning-induced plasticity that remodels adult sensory cortex. Here, expansion in the primary auditory cortical (A1) tonotopic map of rats was induced by pairing a 3.66 kHz tone with activation of the nucleus basalis, mimicking the effects of natural associative learning. Remodeling of A1 produced de novo specific behavioral memory, but neither memory nor plasticity were consistently at the frequency of the paired tone, which typically decreased in A1 representation. Rather, there was a specific match between individual subjects’ area of expansion and the tone that was strongest in each animal’s memory, as determined by post-training frequency generalization gradients. These findings provide the first demonstration of a match between the artificial induction of specific neural representational plasticity and artificial induction of behavioral memory. As such, together with prior and present findings for detection, correlation and mimicry of plasticity with the acquisition of memory, they satisfy a key criterion for neural substrates of memory. This demonstrates that directly remodeling sensory cortical maps is sufficient for the specificity of memory formation. PMID:23639876

Foraging characteristics of larval bluegill sunfish and larval longear sunfish in the Kanawha River, West Virginia

USGS Publications Warehouse

Rider, S.J.; Margraf, F.J.

1998-01-01

We determined spatial and temporal foraging characteristics of larval bluegill sunfish (Lepomis macrochirus) and longear sunfish (Lepomis megalotis) in the upper Kanawha River, West Virginia during the summer of 1989. Stomach contents were examined among habitat types (i.e., main channel, main-channel border, and shoreline habitats) and depth (surface, middle, and bottom). Diet of larval bluegill sunfish was dominated by Chironomidae, temporally and spatially. Chironomidae dominated larval longear sunfish diet in main channel and main-channel border collections from all three depths. However, along the shoreline, larval longear sunfish diet was dominated by Cladocera.

Reproduction and development in Halocaridina rubra Holthuis, 1963 (Crustacea: Atyidae) clarifies larval ecology in the Hawaiian anchialine ecosystem.

PubMed

Havird, Justin C; Vaught, Rebecca C; Weese, David A; Santos, Scott R

2015-10-01

Larvae in aquatic habitats often develop in environments different from those they inhabit as adults. Shrimp in the Atyidae exemplify this trend, as larvae of many species require salt or brackish water for development, while adults are freshwater-adapted. An exception within the Atyidae family is the "anchialine clade," which are euryhaline as adults and endemic to habitats with subterranean fresh and marine water influences. Although the Hawaiian anchialine atyid Halocaridina rubra is a strong osmoregulator, its larvae have never been observed in nature. Moreover, larval development in anchialine species is poorly studied. Here, reproductive trends in laboratory colonies over a 5-y period are presented from seven genetic lineages and one mixed population of H. rubra; larval survivorship under varying salinities is also discussed. The presence and number of larvae differed significantly among lineages, with the mixed population being the most prolific. Statistical differences in reproduction attributable to seasonality also were identified. Larval survivorship was lowest (12% settlement rate) at a salinity approaching fresh water and significantly higher in brackish and seawater (88% and 72%, respectively). Correlated with this finding, identifiable gills capable of ion transport did not develop until metamorphosis into juveniles. Thus, early life stages of H. rubra are apparently excluded from surface waters, which are characterized by lower and fluctuating salinities. Instead, these stages are restricted to the subterranean (where there is higher and more stable salinity) portion of Hawaii's anchialine habitats due to their inability to tolerate low salinities. Taken together, these data contribute to the understudied area of larval ecology in the anchialine ecosystem. © 2015 Marine Biological Laboratory.

Identification of the essential protein domains for Mib2 function during the development of the Drosophila larval musculature and adult flight muscles.

PubMed

Domsch, Katrin; Acs, Andreas; Obermeier, Claudia; Nguyen, Hanh T; Reim, Ingolf

2017-01-01

The proper differentiation and maintenance of myofibers is fundamental to a functional musculature. Disruption of numerous mostly structural factors leads to perturbations of these processes. Among the limited number of known regulatory factors for these processes is Mind bomb2 (Mib2), a muscle-associated E3 ubiquitin ligase, which was previously established to be required for maintaining the integrity of larval muscles. In this study, we have examined the mechanistic aspects of Mib2 function by performing a detailed functional dissection of the Mib2 protein. We show that the ankyrin repeats, in its entirety, and the hitherto uncharacterized Mib-specific domains (MIB), are important for the major function of Mib2 in skeletal and visceral muscles in the Drosophila embryo. Furthermore, we characterize novel mib2 alleles that have arisen from a forward genetic screen aimed at identifying regulators of myogenesis. Two of these alleles are viable, but flightless hypomorphic mib2 mutants, and harbor missense mutations in the MIB domain and RING finger, respectively. Functional analysis of these new alleles, including in vivo imaging, demonstrates that Mib2 plays an additional important role in the development of adult thorax muscles, particularly in maintaining the larval templates for the dorsal longitudinal indirect flight muscles during metamorphosis.

Identification of the essential protein domains for Mib2 function during the development of the Drosophila larval musculature and adult flight muscles

PubMed Central

Domsch, Katrin; Acs, Andreas; Obermeier, Claudia; Nguyen, Hanh T.

2017-01-01

The proper differentiation and maintenance of myofibers is fundamental to a functional musculature. Disruption of numerous mostly structural factors leads to perturbations of these processes. Among the limited number of known regulatory factors for these processes is Mind bomb2 (Mib2), a muscle-associated E3 ubiquitin ligase, which was previously established to be required for maintaining the integrity of larval muscles. In this study, we have examined the mechanistic aspects of Mib2 function by performing a detailed functional dissection of the Mib2 protein. We show that the ankyrin repeats, in its entirety, and the hitherto uncharacterized Mib-specific domains (MIB), are important for the major function of Mib2 in skeletal and visceral muscles in the Drosophila embryo. Furthermore, we characterize novel mib2 alleles that have arisen from a forward genetic screen aimed at identifying regulators of myogenesis. Two of these alleles are viable, but flightless hypomorphic mib2 mutants, and harbor missense mutations in the MIB domain and RING finger, respectively. Functional analysis of these new alleles, including in vivo imaging, demonstrates that Mib2 plays an additional important role in the development of adult thorax muscles, particularly in maintaining the larval templates for the dorsal longitudinal indirect flight muscles during metamorphosis. PMID:28282454

Chronic toxicity of azo and anthracenedione dyes to embryo-larval fathead minnow.

PubMed

Parrott, Joanne L; Bartlett, Adrienne J; Balakrishnan, Vimal K

2016-03-01

The toxicity of selected azo and anthracenedione dyes was studied using chronic exposures of embryo-larval fathead minnows (Pimephales promelas). Newly fertilized fathead minnow embryos were exposed through the egg stage, past hatching, through the larval stage (until 14 days post-hatch), with dye solutions renewed daily. The anthracenedione dyes Acid Blue 80 (AB80) and Acid Blue 129 (AB129) caused no effects in larval fish at the highest measured concentrations tested of 7700 and 6700 μg/L, respectively. Both azo dyes Disperse Yellow 7 (DY7) and Sudan Red G (SRG) decreased survival of larval fish, with LC50s (based on measured concentrations of dyes in fish exposure water) of 25.4 μg/L for DY7 and 16.7 μg/L for SRG. Exposure to both azo dyes caused a delayed response, with larval fish succumbing 4-10 days after hatch. If the exposures were ended at the embryo stage or just after hatch, the potency of these two dyes would be greatly underestimated. Concentrations of dyes that we measured entering the Canadian environment were much lower than those that affected larval fish survival in the current tests. In a total of 162 samples of different municipal wastewater effluents from across Canada assessed for these dyes, all were below detection limits. The similarities of the structures and larval fish responses for the two azo and two anthracenedione dyes in this study support the use of read-across data for risk assessment of these classes of compounds. Crown Copyright © 2015. Published by Elsevier Ltd. All rights reserved.

Arterial grafts exhibiting unprecedented cellular infiltration and remodeling in vivo: the role of cells in the vascular wall.

PubMed

Row, Sindhu; Peng, Haofan; Schlaich, Evan M; Koenigsknecht, Carmon; Andreadis, Stelios T; Swartz, Daniel D

2015-05-01

To engineer and implant vascular grafts in the arterial circulation of a pre-clinical animal model and assess the role of donor medial cells in graft remodeling and function. Vascular grafts were engineered using Small Intestinal Submucosa (SIS)-fibrin hybrid scaffold and implanted interpositionally into the arterial circulation of an ovine model. We sought to demonstrate implantability of SIS-Fibrin based grafts; examine the remodeling; and determine whether the presence of vascular cells in the medial wall was necessary for cellular infiltration from the host and successful remodeling of the implants. We observed no occlusions or anastomotic complications in 18 animals that received these grafts. Notably, the grafts exhibited unprecedented levels of host cell infiltration that was not limited to the anastomotic sites but occurred through the lumen as well as the extramural side, leading to uniform cell distribution. Incoming cells remodeled the extracellular matrix and matured into functional smooth muscle cells as evidenced by expression of myogenic markers and development of vascular reactivity. Interestingly, tracking the donor cells revealed that their presence was beneficial but not necessary for successful grafting. Indeed, the proliferation rate and number of donor cells decreased over time as the vascular wall was dominated by host cells leading to significant remodeling and development of contractile function. These results demonstrate that SIS-Fibrin grafts can be successfully implanted into the arterial circulation of a clinically relevant animal model, improve our understanding of vascular graft remodeling and raise the possibility of engineering mural cell-free arterial grafts. Copyright © 2015 Elsevier Ltd. All rights reserved.

Rigidity and resistance of larval- and adult schistosomes-medium interface

DOE Office of Scientific and Technical Information (OSTI.GOV)

Migliardo, Federica, E-mail: fmigliardo@unime.it; Tallima, Hatem; El Ridi, Rashika

the most flexible. In addition, temperature and hypoxia induce a weakening of the schistosome-medium interaction. These evidences are related to the strength of the hydrogen-bonded interaction between parasites and environment that we previously determined. We have shown that S. mansoni worms are characterized by a weakened interaction in respect to the larvae, while the S. haematobium worms more weakly interact with the surrounding medium than S. mansoni. The present QENS analysis allowed us to characterize the rigidity of larval- and adult S. mansoni and S. haematobium-host interface and to relate it to the parasite resistance to the hostile elements of the surrounding medium and to the immune effectors attack.« less

Dynamics of a neutral delay equation for an insect population with long larval and short adult phases

NASA Astrophysics Data System (ADS)

Gourley, Stephen A.; Kuang, Yang

We present a global study on the stability of the equilibria in a nonlinear autonomous neutral delay differential population model formulated by Bocharov and Hadeler. This model may be suitable for describing the intriguing dynamics of an insect population with long larval and short adult phases such as the periodical cicada. We circumvent the usual difficulties associated with the study of the stability of a nonlinear neutral delay differential model by transforming it to an appropriate non-neutral nonautonomous delay differential equation with unbounded delay. In the case that no juveniles give birth, we establish the positivity and boundedness of solutions by ad hoc methods and global stability of the extinction and positive equilibria by the method of iteration. We also show that if the time adjusted instantaneous birth rate at the time of maturation is greater than 1, then the population will grow without bound, regardless of the population death process.

Bioinsecticidal activity of Talisia esculenta reserve protein on growth and serine digestive enzymes during larval development of Anticarsia gemmatalis.

PubMed

Macedo, Maria Lígia R; Freire, Maria das Graças M; Kubo, Carlos Eduardo G; Parra, José Roberto P

2011-01-01

Plants synthesize a variety of molecules to defend themselves against an attack by insects. Talisin is a reserve protein from Talisia esculenta seeds, the first to be characterized from the family Sapindaceae. In this study, the insecticidal activity of Talisin was tested by incorporating the reserve protein into an artificial diet fed to the velvetbean caterpillar Anticarsia gemmatalis, the major pest of soybean crops in Brazil. At 1.5% (w/w) of the dietary protein, Talisin affected larval growth, pupal weight, development and mortality, adult fertility and longevity, and produced malformations in pupae and adult insects. Talisin inhibited the trypsin-like activity of larval midgut homogenates. The trypsin activity in Talisin-fed larvae was sensitive to Talisin, indicating that no novel protease-resistant to Talisin was induced in Talisin-fed larvae. Affinity chromatography showed that Talisin bound to midgut proteinases of the insect A. gemmatalis, but was resistant to enzymatic digestion by these larval proteinases. The transformation of genes coding for this reserve protein could be useful for developing insect resistant crops. Copyright © 2010 Elsevier Inc. All rights reserved.