trophic effect
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Oecologia ◽  
2022 ◽  
Author(s):  
Hagen M. O’Neill ◽  
Sean D. Twiss ◽  
Philip A. Stephens ◽  
Tom H. E. Mason ◽  
Nils Ryrholm ◽  
...  

AbstractEcosystem engineers affect other organisms by creating, maintaining or modifying habitats, potentially supporting species of conservation concern. However, it is important to consider these interactions alongside non-engineering trophic pathways. We investigated the relative importance of trophic and non-trophic effects of an ecosystem engineer, red deer, on a locally rare moth, the transparent burnet (Zygaena purpuralis). This species requires specific microhabitat conditions, including the foodplant, thyme, and bare soil for egg-laying. The relative importance of grazing (i.e., trophic effect of modifying microhabitat) and trampling (i.e., non-trophic effect of exposing bare soil) by red deer on transparent burnet abundance is unknown. We tested for these effects using a novel method of placing pheromone-baited funnel traps in the field. Imago abundance throughout the flight season was related to plant composition, diversity and structure at various scales around each trap. Indirect effects of red deer activity were accounted for by testing red deer pellet and trail presence against imago abundance. Imago abundance was positively associated with thyme and plant diversity, whilst negatively associated with velvet grass and heather species cover. The presence of red deer pellets and trails were positively associated with imago abundance. The use of these sites by red deer aids the transparent burnet population via appropriate levels of grazing and the provision of a key habitat condition, bare soil, in the form of deer trails. This study shows that understanding how both trophic and non-trophic interactions affect the abundance of a species provides valuable insights regarding conservation objectives.


2021 ◽  
Vol 12 ◽  
Author(s):  
Gabriela P. Finkielstain ◽  
Ana Vieites ◽  
Ignacio Bergadá ◽  
Rodolfo A. Rey

Disorders of Sex Development (DSD) are anomalies occurring in the process of fetal sexual differentiation that result in a discordance between the chromosomal sex and the sex of the gonads and/or the internal and/or external genitalia. Congenital disorders affecting adrenal function may be associated with DSD in both 46,XX and 46,XY individuals, but the pathogenic mechanisms differ. While in 46,XX cases, the adrenal steroidogenic disorder is responsible for the genital anomalies, in 46,XY patients DSD results from the associated testicular dysfunction. Primary adrenal insufficiency, characterized by a reduction in cortisol secretion and overproduction of ACTH, is the rule. In addition, patients may exhibit aldosterone deficiency leading to salt-wasting crises that may be life-threatening. The trophic effect of ACTH provokes congenital adrenal hyperplasia (CAH). Adrenal steroidogenic defects leading to 46,XX DSD are 21-hydroxylase deficiency, by far the most prevalent, and 11β-hydroxylase deficiency. Lipoid Congenital Adrenal Hyperplasia due to StAR defects, and cytochrome P450scc and P450c17 deficiencies cause DSD in 46,XY newborns. Mutations in SF1 may also result in combined adrenal and testicular failure leading to DSD in 46,XY individuals. Finally, impaired activities of 3βHSD2 or POR may lead to DSD in both 46,XX and 46,XY individuals. The pathophysiology, clinical presentation and management of the above-mentioned disorders are critically reviewed, with a special focus on the latest biomarkers and therapeutic development.


2021 ◽  
Vol 8 ◽  
Author(s):  
Marion Lemaire ◽  
Olivia Ménard ◽  
Armelle Cahu ◽  
Isabelle Nogret ◽  
Valérie Briard-Bion ◽  
...  

Breast milk is the gold standard in neonatal nutrition, but most infants are fed infant formulas in which lipids are usually of plant origin. The addition of dairy lipids and/or milk fat globule membrane extracts in formulas improves their composition with beneficial consequences on protein and lipid digestion. The probiotic Lactobacillus fermentum (Lf) was reported to reduce transit time in rat pups, which may also improve digestion. This study aimed to investigate the effects of the addition of dairy lipids in formulas, with or without Lf, on protein and lipid digestion and on gut physiology and metabolism. Piglets were suckled from postnatal days 2 to 28, with formulas containing either plant lipids (PL), a half-half mixture of plant and dairy lipids (DL), or this mixture supplemented with Lf (DL+Lf). At day 28, piglets were euthanized 90 min after their last feeding. Microstructure of digesta did not differ among formulas. Gastric proteolysis was increased (P < 0.01) in DL and DL+Lf (21.9 ± 2.1 and 22.6 ± 1.3%, respectively) compared with PL (17.3 ± 0.6%) and the residual proportion of gastric intact caseins decreased (p < 0.01) in DL+Lf (5.4 ± 2.5%) compared with PL and DL (10.6 ± 3.1% and 21.8 ± 6.8%, respectively). Peptide diversity in ileum and colon digesta was lower in PL compared to DL and DL+Lf. DL and DL+Lf displayed an increased (p < 0.01) proportion of diacylglycerol/cholesterol in jejunum and ileum digesta compared to PL and tended (p = 0.07) to have lower triglyceride/total lipid ratio in ileum DL+Lf (0.019 ± 0.003) as compared to PL (0.045 ± 0.011). The percentage of endocrine tissue and the number of islets in the pancreas were decreased (p < 0.05) in DL+Lf compared with DL. DL+Lf displayed a beneficial effect on host defenses [increased goblet cell density in jejunum (p < 0.05)] and a trophic effect [increased duodenal (p = 0.09) and jejunal (p < 0.05) weights]. Altogether, our results demonstrate that the addition of dairy lipids and probiotic Lf in infant formula modulated protein and lipid digestion, with consequences on lipid profile and with beneficial, although moderate, physiological effects.


2020 ◽  
Vol 19 (6) ◽  
pp. 2733
Author(s):  
L. Yu. Grivtsova ◽  
O. E. Popovkina ◽  
N. N. Dukhova ◽  
O. A. Politiko ◽  
V. V. Yuzhakov ◽  
...  

Cardiovascular diseases, along with cancer, are the leading causes of death worldwide. Although modern pharmacological treatment of various cardiomyopathies can slow the development of myocardial dysfunction, they have limited effectiveness in patients with end-stage disease. Many researchers believe that heart transplantation is the only radical treatment in this case. However, the lack of donors and the high operation cost require careful selection of surgical candidates. With the introduction of molecular and cell biology into medical practice, today, stem cell therapy can become an alternative method of nonsurgical restoration of myocardial functions. The most studied and attractive is the use of mesenchymal stem cells (MSCs). MSCs differ from hematopoietic stem cells used as support for hematopoiesis in high-dose chemotherapy by the following features: pronounced trophic effect, immune tolerance, the ability to suppress alloreactivity and autoimmune disorders. An important stage in the implementation of cell therapy is the creation of a cell biobank of MSCs. In A.F.Tsyb Medical Radiological Research Center, this work has been carried out since1984. Asignificant number of experimental studies have been carried out, confirming the possibility of clinical implementation of this approach. A method for obtaining stable cultures of MSCs and cardiomyoblasts from bone marrow cells was developed and approvals were obtained. Experimental studies of cell therapy are also being conducted to overcome anthracycline-induced cardiotoxicity in cancer patients.This article is devoted to practical application of MSC-based therapy, in particular, in cancer patients with cardiotoxicity, as well as to the issues of creating a cell biobank for treatment with MSCs.


2020 ◽  
Vol 9 (6) ◽  
pp. 392-398
Author(s):  
Philemon C Anuforo ◽  
◽  
Anthony Cemaluk C Egbuonu ◽  
Elizabeth U Egu ◽  
Ejike Chukwunyere ◽  
...  

This study investigated the antioxidant and haematological potentials of a fruit wastes from Terminalia catappa and observable trophic effect on weight of Wistar rats after acute exposure to monosodium glutamate. Twenty-four male albino Wistar rats with mean weight of 120.61±15.15 g were divided into six groups (n=4). Group 1, the normal control (received distilled water), group II, the negative control (received 8mg MSG/g b.wt), group III, the extract control (received 300 mg extract/kg b.wt), group IV (received 8 mg MSG/g b.wt. + 100 mg extract/kg b.wt.), group V (received 8 mg MSG/g b.wt. + 300 mg kg-1 b.wt. extract) and group VI (received 8 mg MSG/g b.wt. + 500 mg extract/kg b.wt). Treatment was administered daily by oral gavage for 14 days. Data were subjected to one-way ANOVA followed by Duncan post-hoc test at p<0.05 and means were estimated and significant differences noted. DPPH antioxidant assay for the fruit wastes ethanol extract of Terminalia catappa endocarp revealed the extract produced 92.8% inhibition which is comparable to 96.07% inhibition produced by ascorbic acid at the same concentration, as well as, possessed FRAP activity in a concentration dependent manner. In vivo antioxidant assays carried out revealed that the superoxide dismutase (SOD) activity was significantly (p<0.05) lowered in the MSG-treated group but the catalase (CAT) activity showed a non-significant decrease as compared to the normal control, confirming there was oxidative stress. However, treatment with the extract increased the activities of SOD and CAT perhaps due to the presence of phenolic and flavonoids components. There was a significant (p<0.05) increase in WBC and RBC and could be attributed to the potential of the extract to stimulate the immune system. Haemoglobin (Hb) and packed cell volume (PCV) in MSG-extract co-administered rats showed a positive ameliorative effect of the extract in a dose dependent manner when compared to MSG group. Weight gain following extract administration was not dose dependent. The results showed that the fruit wastes had antioxidant potency and haematological potential. This bio-approach is promising as it solves the problem of environmental burden, as well as, serves economic benefits and hence, may become increasingly attractive.


2020 ◽  
Vol 2020 ◽  
pp. 1-13
Author(s):  
Anna Sobuś ◽  
Bartłomiej Baumert ◽  
Wioletta Pawlukowska ◽  
Monika Gołąb-Janowska ◽  
Edyta Paczkowska ◽  
...  

Amyotrophic lateral sclerosis (ALS) remains a fatal, neurodegenerative disease frequently leading to dysarthria and impaired swallowing. Better understanding of ALS pathophysiology is prompting the use of humoral cell therapies. Hence, a repeated cellular therapy was applied to ALS patients as an attempt to prevent speech deterioration. Autologous bone marrow-derived lineage-negative (Lin−) cells were intrathecally administered three times at six-week intervals to 42 sporadic ALS patients. Patients were examined for articulatory functions using subjective (VHI) and objective (FDA) scales. Selected trophic, proinflammatory factors and expression profiles of miRNA were measured in cerebrospinal fluid (CSF) and plasma by multiplex Luminex and q-PCR in different timepoints. Of the 42 patients who received the Lin− cells, 6 showed improvement in articulatory functions, 27 remained stable, and 9 deteriorated after 18 weeks of therapy according to FDA scale. Clinical improvement was particularly evident by the 7th day of each cell application and concerned better cough and swallow reflex, soft palate, laryngeal time, pitch, and volume. These results correlated with significant changes in the concentration of various trophic and proinflammatory factors and miRNA expression profiles. A multiple application of Lin− cells proved to be safe and feasible. The repeated procedure can potentate a humoral effect and prevent speech deterioration. A short-lasting trophic effect of each Lin− cells administration was observed on local and systemic level. However, further in-depth studies are necessary to sustain the beneficial effect.


2020 ◽  
Vol 11 (1) ◽  
Author(s):  
Rebeca Fernandez-Ruiz ◽  
Ainhoa García-Alamán ◽  
Yaiza Esteban ◽  
Joan Mir-Coll ◽  
Berta Serra-Navarro ◽  
...  

AbstractExpanding the mass of pancreatic insulin-producing beta cells through re-activation of beta cell replication has been proposed as a therapy to prevent or delay the appearance of diabetes. Pancreatic beta cells exhibit an age-dependent decrease in their proliferative activity, partly related to changes in the systemic environment. Here we report the identification of CCN4/Wisp1 as a circulating factor more abundant in pre-weaning than in adult mice. We show that Wisp1 promotes endogenous and transplanted adult beta cell proliferation in vivo. We validate these findings using isolated mouse and human islets and find that the beta cell trophic effect of Wisp1 is dependent on Akt signaling. In summary, our study reveals the role of Wisp1 as an inducer of beta cell replication, supporting the idea that the use of young blood factors may be a useful strategy to expand adult beta cell mass.


2020 ◽  
Vol 9 (12) ◽  
pp. 3799
Author(s):  
Gysbert-Botho van Setten ◽  
Oliver Stachs ◽  
Bénédicte Dupas ◽  
Semra Akkaya Turhan ◽  
Berthold Seitz ◽  
...  

The purpose of this study was to investigate the effect of high molecular weight hyaluronan (HMWHA) eye drops on subbasal corneal nerves in patients suffering from severe dry eye disease (DED) and to evaluate the damage of subbasal corneal nerves associated with severe DED. Designed as an international, multicenter study, 16 patients with symptoms of at least an Ocular Surface Disease Index (OSDI) score of 33, and corneal fluorescein staining (CFS) of at least Oxford grade 3, were included and randomized into two study arms. The control group continued to use their individual optimum artificial tears over the study period of eight weeks; in the verum group, the artificial tears were substituted by eye drops containing 0.15% HMWHA. At the baseline visit, and after eight weeks, the subbasal nerve plexus of 16 patients were assessed by confocal laser scanning microscopy (CSLM). The images were submitted to a masked reading center for evaluation. Results showed a significant increase of total nerve fiber lengths (CNFL) in the HMWHA group (p = 0.030) when compared to the control group, where the total subbasal CNFL did not significantly change from baseline to week 8. We concluded that in severe DED patients, HMWHA from topically applied eye drops could cross the epithelial barrier and reach the subbasal nerve plexus, where it exercised a trophic effect.


2020 ◽  
Vol 2020 (19) ◽  
pp. 130-137
Author(s):  
Alexandr Savarin ◽  
◽  
Denis Kitel ◽  

The article discusses the species and taxonomic composition of the long-eared owl (Asio otus) preys based on the analysis of pellets (n = 209) collected in the winter-spring period in 2016 in the Malarytsky district (Lozitsa village) and the Brest region district center. The distance between Malaryta town and Lozitsa village is about 10 km. Parts of the skull of 512 small mammals (2.45 individuals per pellet) and one bird were found. Feeding on birds for the long-eared owl is episodic. Representatives of 2 orders, 10 genera and 12 species of small mammals (5 species of shrews and 7 rodents) became preys of the owl. The proportion of rodents is 98.24 % of all preys. The absolute dominant among prey species is Microtus arvalis (85.16 % of all victims), which is consistent with numerous work carried out in other regions. Significant portions are of Apodemus agrarius (4.10 %), Muscardinus avellanarius (2.54 %), Sylvaemus tauricus (1.76 %), and Alexandromys oeconomus (1.56 %). The list of preys is presented by meadow-field, synanthropic and different species actively moving from adjacent forests in the Malaryta river floodplain and canal systems (Sylvaemus tauricus, Sorex araneus, S. minutus, Neomys fodiens). The occurence of two shrew species Crocidura leucodon and C. suaveolens in the city of Malaryta has been proved, which corresponds to similar information for the city of Brest. This suggests that C. suaveolens inhabits the entire territory of the Belarusian Polesie at present. The occurence of the non-abundant species Sicista betulina in vicinities of the town of Malaryta was confirmed. The results obtained confirm the significant trophic effect of the long-eared owl on the local population of the hazel dormouse and also indicate the relatively high abundance of this rodent in the study area. Seven species were identified in pellets of the long-eared owl living near the village of Lozitsa, and 12 species of small mammals were identified in the town of Malaryta. The diversity of the landscape of the town of Malaryta determines the large number of prey species.


Nutrients ◽  
2020 ◽  
Vol 12 (7) ◽  
pp. 1970
Author(s):  
Antonio Pérez-Pérez ◽  
Teresa Vilariño-García ◽  
Pilar Guadix ◽  
José L. Dueñas ◽  
Víctor Sánchez-Margalet

Leptin is highly expressed in the placenta, mainly by trophoblastic cells, where it has an important autocrine trophic effect. Moreover, increased leptin levels are found in the most frequent pathology of pregnancy: gestational diabetes, where leptin may mediate the increased size of the placenta and the fetus, which becomes macrosomic. In fact, leptin mediates the increased protein synthesis, as observed in trophoblasts from gestational diabetic subjects. In addition, leptin seems to facilitate nutrients transport to the fetus in gestational diabetes by increasing the expression of the glycerol transporter aquaporin-9. The high plasma leptin levels found in gestational diabetes may be potentiated by leptin resistance at a central level, and obesity-associated inflammation plays a role in this leptin resistance. Therefore, the importance of anti-inflammatory nutrients to modify the pathology of pregnancy is clear. In fact, nutritional intervention is the first-line approach for the treatment of gestational diabetes mellitus. However, more nutritional intervention studies with nutraceuticals, such as polyphenols or polyunsaturated fatty acids, or nutritional supplementation with micronutrients or probiotics in pregnant women, are needed in order to achieve a high level of evidence. In this context, the Mediterranean diet has been recently found to reduce the risk of gestational diabetes in a multicenter randomized trial. This review will focus on the impact of maternal obesity on placental inflammation and nutrients transport, considering the mechanisms by which leptin may influence maternal and fetal health in this setting, as well as its role in pregnancy pathologies.


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