scholarly journals Apical but not sub-apical hyphal compartments are self-sustaining in growth

2020 ◽  
Vol 113 (5) ◽  
pp. 697-706 ◽  
Author(s):  
Martin Tegelaar ◽  
George P. A. van der Lans ◽  
Han A. B. Wösten
Keyword(s):  
Growth Rate ◽  
Penicillium Chrysogenum ◽  
Schizophyllum Commune ◽  
Hyphal Growth ◽  
Apical Part ◽  
Apical Region ◽  
Rhizopus Stolonifer ◽  
Backup System ◽  
Before And After ◽  
Subapical Region

AbstractIt was recently demonstrated that apical compartments of Aspergillus niger hyphae are self-sustaining in growth. This was shown by assessing the growth rate of individual hyphae before and after dissection of the second compartment. Using the same methodology, it is here demonstrated that single apical compartments of the septate fungi Penicillium chrysogenum and Schizophyllum commune as well as the 500-µm-apical region of the non-septate fungus Rhizopus stolonifer are also self-sustaining in growth. In contrast, single 2nd compartments (obtained by dissection of the first and third compartment) of the septate fungi or the region between 500 and 1000 µm from tips of R. stolonifer were severely impacted in their growth rate. In addition, it is shown that existing or newly formed branches originating from the 2nd compartments function as a backup system for hyphal growth when the apical part of the hypha of the three studied fungi is damaged. Together, it is concluded that the apical compartments/zones of the studied fungi are self-sustaining in growth. In contrast, the subapical region is not self-sustaining but functions as a backup once the apical zone is damaged. This back up system is relevant in nature because the apices of hyphae are the first to be exposed to (a)biotic stress conditions when entering an unexplored substrate.

scholarly journals The Neurospora crassa exocyst complex tethers Spitzenkörper vesicles to the apical plasma membrane during polarized growth

2014 ◽  
Vol 25 (8) ◽  
pp. 1312-1326 ◽  
Author(s):  
Meritxell Riquelme ◽  
Erin L. Bredeweg ◽  
Olga Callejas-Negrete ◽  
Robert W. Roberson ◽  
Sarah Ludwig ◽  
...  
Keyword(s):  
Plasma Membrane ◽  
Neurospora Crassa ◽  
Hyphal Growth ◽  
Apical Plasma Membrane ◽  
Apical Region ◽  
Secretory Vesicles ◽  
Polarized Growth ◽  
Hyphal Morphogenesis ◽  
Exocyst Complex ◽  
Dynamic Formation

Fungal hyphae are among the most highly polarized cells. Hyphal polarized growth is supported by tip-directed transport of secretory vesicles, which accumulate temporarily in a stratified manner in an apical vesicle cluster, the Spitzenkörper. The exocyst complex is required for tethering of secretory vesicles to the apical plasma membrane. We determined that the presence of an octameric exocyst complex is required for the formation of a functional Spitzenkörper and maintenance of regular hyphal growth in Neurospora crassa. Two distinct localization patterns of exocyst subunits at the hyphal tip suggest the dynamic formation of two assemblies. The EXO-70/EXO-84 subunits are found at the peripheral part of the Spitzenkörper, which partially coincides with the outer macrovesicular layer, whereas exocyst components SEC-5, -6, -8, and -15 form a delimited crescent at the apical plasma membrane. Localization of SEC-6 and EXO-70 to the plasma membrane and the Spitzenkörper, respectively, depends on actin and microtubule cytoskeletons. The apical region of exocyst-mediated vesicle fusion, elucidated by the plasma membrane–associated exocyst subunits, indicates the presence of an exocytotic gradient with a tip-high maximum that dissipates gradually toward the subapex, confirming the earlier predictions of the vesicle supply center model for hyphal morphogenesis.

The effect of adding a feed flavour to the diets of young pigs before and after weaning

1979 ◽  
Vol 19 (101) ◽  
pp. 695 ◽  
Author(s):  
RH King
Keyword(s):  
Growth Rate ◽  
Feed Intake ◽  
Factorial Experiment ◽  
Feed Consumption ◽  
Daily Growth Rate ◽  
Daily Growth ◽  
Weaning Weight ◽  
Young Pigs ◽  
Creep Feed ◽  
Before And After

Sixteen sows and their progeny were allotted to treatments in a 23 factorial experiment involving two levels of feed flavour (0 and 50 ppm of Firanor No. 24) in each of the sow, creep and starter diets. Weaning occurred at a mean piglet age of 26.9 days and observations continued for 31 days after weaning. The feed flavour, when added to the sow diet, was incorporated in sow's milk; milk from one sow fed the flavoured diet contained 9 ppm of Firanor No. 24. The addition of the feed flavour to the creep diet failed to improve creep feed consumption or weaning weight; the average daily creep feed intake and daily growth rate prior to weaning being 47.8 g/head and 207 g/head, respectively. During the postweaning period, pigs that were weaned from sows receiving the flavour and then given the flavoured starter diet ate more feed (P<0.05) and tended to grow faster (839 and 400 g day-1, respectively) than pigs given the unflavoured starter diet, or those weaned from sows given no flavour; their average feed intake and growth rate being 764 and 362 g day-1, respectively.

The effect of three suckling regimes on the lactation performance of Cyprus fat-tailed, Chios and Awassi sheep and the growth rate of the lambs

1974 ◽  
Vol 18 (3) ◽  
pp. 293-299 ◽  
Author(s):  
M. J. Lawlor ◽  
A. Louca ◽  
A. Mavrogenis
Keyword(s):  
Growth Rate ◽  
Milk Yield ◽  
Growth Rates ◽  
Milk Replacer ◽  
Lactation Performance ◽  
Lactation Length ◽  
Awassi Sheep ◽  
Creep Feed ◽  
Total Milk ◽  
Before And After

SUMMARYNinety-nine ewes, 33 from each of the Cyprus fat-tailed, Chios and Awassi breeds, were used to compare the effects of three suckling regimes on lactation. These consisted of weaning the lambs at birth (W0), 2 days (W2) and 35 days (W35). The 35-day, 150-day and total milk yields, as well as lactation length, were measured for each group. The lambs weaned from the ewes at birth and 2 days were reared on ewe-milk replacer. The growth rate of these lambs was compared with that of the lambs being suckled by their dams, before and after weaning.In all cases the milk yields of the Chios and Awassi breeds of sheep were significantly higher (P<0·01) than those of the Cyprus fat-tailed. Within each breed the 35-day milk yields of the ewes suckling one lamb were significantly higher (P<0·01) than those of the ewes on the W0 or W2 treatments, which themselves did not differ significantly. While the 150-day milk yields of the W35 treatment were significantly higher than those of the W0 or W2 treatments, the differences between suckling regimes in terms of total milk yield and lactation length were not significant. It is concluded that differences in milk yield obtained on different suckling regimes are attributable solely to the length of time that the lambs are suckled by their dams.Prior to weaning the growth rate of the lambs given the ewe-milk replacer was significantly lower than that of the lambs suckled by their dams. There were no differences in the growth rates of these groups of lambs when both were fattened on a creep feed after weaning.

173 THE EFFECT OF EXERCISE ON FOLLICULOGENESIS IN MARES

2009 ◽  
Vol 21 (1) ◽  
pp. 185 ◽  
Author(s):  
D. E. Kelley ◽  
J. R. Gibbons ◽  
S. E. Pratt ◽  
R. L. Smith ◽  
C. J. Mortensen
Keyword(s):  
Growth Rate ◽  
Heat Stress ◽  
Transrectal Ultrasound ◽  
Follicular Development ◽  
Control Group ◽  
Follicular Growth ◽  
Embryo Recovery ◽  
Conditioning Period ◽  
Before And After ◽  
The Impact

The effects of exercise on follicular development in mares have not been well established; however, a combination of exercise and heat stress can negatively affect embryo recovery rate in mares. The purpose of this research was to examine the effects of exercise, independent of heat stress, on follicular development in mares. One thoroughbred and 12 quarter horse mares, aged 3 to 15 years, were used in this study. Mares were assigned to the control group or exercised at 0700 h, 6 days a week, as follows: warmed up 5 min at a walk for 3 m s–1 and then exercised 30 min, 9 m s–1 for 10 min, 13 m s–1 for 5 min, 9 m s–1 for 5 min, 13 m s–1 for 5 min, and 9 m s–1 for 5 min. Exercised mares were given a 1-month conditioning period. Rectal temperatures were recorded immediately before and after exercise. The mean rectal temperature of mares increased by 0.85°C during exercise, whereas control mares under the same environmental conditions did not experience temperature increases. Individual mares underwent a daily transrectal ultrasound examination with a 7.5-MHz linear rectal probe to monitor follicular development. Estrous cycles were normalized to 17 days for linear follicular growth analysis. Exercise had a significant impact on follicular growth at deviation, with a greater diameter of the largest (P < 0.05) and second largest (P < 0.01) follicles in exercised v. control mares (Table 1). Additionally, growth rate of the second largest follicle was greater in the exercised group (P < 0.01). Deviation was observed in 13 of 14 cycles in control mares, whereas in exercised mares, it was clear in only 11 of 16 cycles (χ2, P = 0.086). Time of deviation was defined as the day when a difference in the growth rate between the dominant and largest subordinate follicle of a wave was first observed. The largest subordinate follicle either declined in growth rate or regressed. At Day –5 (relative to ovulation), exercised mares had significantly greater follicle diameters in both the largest and second largest follicle (P < 0.05). Exercised mares had double ovulations in 4 of 16 cycles when compared with control mares, which had double ovulations in 1 of 14 cycles. No differences were found between groups in the length of the estrous cycle or ovulatory follicular diameter. Exercised mares exhibited larger diameter follicles and an increased growth rate of the largest subordinate follicle, suggesting that exercise delayed deviation. Further research is needed to assess the impact of exercise, independent of heat stress, on fertility. Table 1.Follicle dynamics in exercised v. non-exercised mares

Morphological and chemical alterations inBotrytis cinereaexposed to the dicarboximide fungicide vinclozolin

1997 ◽  
Vol 43 (6) ◽  
pp. 552-560 ◽  
Author(s):  
Silvia M. J. C. S. Cabral ◽  
João P. S. Cabral
Keyword(s):  
Growth Rate ◽  
Chemical Composition ◽  
Botrytis Cinerea ◽  
Germ Tube ◽  
Membrane Damage ◽  
Hyphal Growth ◽  
Lower Content ◽  
Cell Debris ◽  
Biochemical Alterations ◽  
Severe Reduction

Treatment of actively growing Botrytis cinerea hyphae with micromolar concentrations of the dicarboximide fungicide vinclozolin resulted in significant alterations in the growth rate, morphology, and chemical composition of the cells. The addition of vinclozolin resulted in an immediate and severe reduction in the hyphal growth rate and a retardation in the emergence of the second germ tube. Cells treated with vinclozolin had a lower content of pool metabolites than control cells, and this difference increased with time of exposure to the fungicide. In contrast, vinclozolin-treated cells had a higher chitin concentration than control cells. These biochemical alterations were followed by the disorganization and clearing of cells, and by the appearance of dense and dark masses outside the hyphae, presumably composed of cell debris. Hyphae exposed to vinclozolin were more curved and branched and had shorter cells than the controls. The results indicate that vinclozolin causes a slow but generalized leakage of pool metabolites; this release precedes cell lysis and is not the result of a rapid and gross damage to the cytoplasmic membrane.Key words: vinclozolin, Botrytis cinerea, pool metabolites, membrane damage.

Characterization of inhibition of Rhizopus stolonifer germination and growth by Enterobacter cloacae

1989 ◽  
Vol 67 (8) ◽  
pp. 2317-2323 ◽  
Author(s):  
Michael Wisniewski ◽  
Charles Wilson ◽  
Wilbur Hershberger
Keyword(s):  
Hyphal Growth ◽  
Enterobacter Cloacae ◽  
Significant Inhibition ◽  
Bacterial Attachment ◽  
Nutrient Competition ◽  
Rhizopus Stolonifer ◽  
Postharvest Rot ◽  
Germination And Growth

Interactions between Enterobacter cloacae and Rhizopus stolonifer were evaluated to determine possible mechanisms by which E. cloacae protects peach fruit from postharvest rot caused by R. stolonifer. Inhibition of Rhizopus sporangiospore germination by E. cloacae was dependent on the concentration of the antagonist. Antagonist concentration (1 × 1010 cfu ∙ mL−1) needed to completely inhibit germination was similar to that needed to prevent fruit infection. Significant inhibition of in vitro hyphal growth was achieved at 1 × 105 cfu ∙ mL−1 with simultaneous culturing of the fungus and antagonist. A reduction in inhibition occurred when addition of the antagonist was delayed. The presence of glucose in the growth medium did not prevent attachment of E. cloacae to hyphae and sporangiospores of R. stolonifer. Agglutination assays of sporangiospores by E. cloacae were positive whereas agglutination of cell-wall fragments was less distinct. Data indicate that nutrient competition, perhaps facilitated by bacterial attachment, may play a key role in E. cloacae and R. stolonifer interactions.

Tumor response and growth rate of nivolumab treatment in advanced gastric cancer: Real-world data from a large observational/translational study, JACCRO GC-08 (deliver trial).

2020 ◽  
Vol 38 (15_suppl) ◽  
pp. 4527-4527
Author(s):  
Ryohei Kawabata ◽  
Yasuhiro Sakamoto ◽  
Eisuke Inoue ◽  
Atsushi Ishiguro ◽  
Yusuke Akamaru ◽  
...  
Keyword(s):  
Gastric Cancer ◽  
Clinical Trial ◽  
Growth Rate ◽  
Tumor Growth ◽  
Real World ◽  
Fold Increase ◽  
Real World Data ◽  
World Data ◽  
Translational Study ◽  
Before And After

4527 Background: Nivolumab (Nivo) demonstrated survival benefit in previously treated gastric cancer (GC) patients (pts), with a response rate (RR) of 11% and a disease control rate (DCR) of 40% (Kang YK, et al. Lancet 2017). There are few real-world data of Nivo and its predictive markers are needed in GC. It has been demonstrated that some tumors grow rapidly after Nivo treatment, but the proportion is uncertain. Methods: DELIVER trial was a prospective, multicenter, observational/translational study which assessed pts with advanced GC treated with Nivo alone and ECOG Performance Status (PS) 0-2 (UMIN000030850). The aims were to evaluate the efficacy and safety of Nivo in real world, and to discover novel host-related immune-biomarkers (gut microbiome, genetic polymorphism, gene expression, and metabolome) using fecal and blood samples which were collected before and after Nivo treatment. The RR, DCR, progression-free survival, overall survival, and tumor growth rate (TGR) were estimated as the efficacy. The response was evaluated by first imaging based on RECIST version 1.1. The TGR was calculated as a percentage increase in tumor volume during 1 month (Champiat et al. Clin Cancer Res 2017). Results: A total of 501 pts was enrolled in this study from Mar 2018 to Aug 2019, and 487 pts were evaluable for analysis (median age 70-y, 71% male, ECOG PS0/1/2 42%/44%/14%, tub/por/sig 45%/41%/5%, 21% HER2-pos, 42% pts with ascites). The DCR was 39.2% (95%CI 34.9-43.7) in evaluable pts. In 282 pts with measurable lesions, the RR was 6.7% (95%CI 4.1-10.3) and DCR was 36.5%. Sub-analysis by patient background indicated that DCR was 41% for PS0, 42% for PS1, and 24% for PS2. In addition, the DCR was lower in pts with ascites compared to those without ascites (28.6% vs. 47.0%, p= 0.005). The TGR decreased after introduction of Nivo in 124 (56.6%) of 219 evaluable pts for TGR; however, 20.5% pts were identified as experiencing hyper-progressive disease (HPD) which was defined as a ≥2-fold increase of the TGR before and after Nivo. When defining HPD as a ≥2-fold increase of tumor growth kinetics ratio and 50% increase of tumor burden, 9.6% pts experienced it. Conclusions: The real-word data of the large observational trial showed a comparable DCR to that of clinical trial in advanced GC treated with Nivo. This trial revealed the tumor behavior and some pts who experienced rapid tumor growth after Nivo treatment in clinical practice; biomarkers for HPD and the definition should be established. Clinical trial information: UMIN000030850 .

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