Isolation, purification, and full NMR assignments of cyclopamine from Veratrum californicum

The Hedgehog signaling pathway is essential for embryogenesis and for tissue homeostasis in the adult. However, it may induce malignancies in a number of tissues when constitutively activated, and it may also have a role in other forms of normal and maladaptive growth. Cyclopamine, a naturally occurring steroidal alkaloid, specifically inhibits the Hedgehog pathway by binding directly to Smoothened, an important Hedgehog response element. To use cyclopamine as a tool to explore and/or inhibit the Hedgehog pathway in vivo, a substantial quantity is required, and as a practical matter cyclopamine has been effectively unavailable for usage in animals larger than mice

Is Nitrogen the Limiting Factor to Maintain Feed Efficiency when Feeding Low Protein, Amino Acid Fortified Diets?

A total of 981 mixed-sex pigs ([Fast LW × PIC L02] × PIC 800; initially 22.8 ± 0.42 lb) were used in a 21-d study to determine if nitrogen, derived from non-protein nitrogen or amino nitrogen, is the limiting factor to maintain feed efficiency when feeding low protein, amino acid fortified diets. Pens of pigs were randomly allotted to one of five dietary treatments in a randomized complete block design with BW as a blocking factor. There were 19 to 20 pigs per pen and 10 pens per treatment. The experimental diets were corn-soybean meal-based and were fed when pigs reached an approximate BW of 23 lb, considered d 0 of the study. The five treatments consisted of: 1) low level of feed-grade AAs with a SID Lys:CP ratio of 6.0:1; 2) moderate level of feed-grade AAs with a SID Lys:CP ratio of 6.5:1; 3) high level of feed-grade AAs with a SID Lys:CP ratio of 7.0:1; 4) diet 3 with di-ammonium phosphate (DAP) added to achieve a SID Lys:calculated CP ratio of 6.5:1; 5) diet 3 with glycine added to achieve a SID Lys:calculated CP ratio of 6.5:1. All diets contained 0.4% titanium dioxide for determination of apparent total tract digestibility (ATTD) of dry matter (DM) and crude protein (CP). Treatment diets were fed for 21 days. Feces were collected on d 21 from three pigs per pen to determine fecal DM. Overall (d 0 to 21), ADG was not influenced by treatment. Feed efficiency worsened (linear, P = 0.002; quadratic, P = 0.054) as the SID Lys:CP ratio was increased above 6.5% with additional feed-grade AAs. Adding DAP or glycine to the high feed-grade AA diet improved (P ≤ 0.003) feed efficiency compared to pigs fed the high feed-grade AA diet because of a reduction (P = 0.007) or numerical reduction (P = 0.109), respectively, in ADFI. There was a decrease (linear, P \u3c 0.001) in blood urea nitrogen (BUN) as feed-grade AAs increased. Adding additional nitrogen to the high feed-grade AA diet increased (DAP; P = 0.038) or tended to increase (glycine, P = 0.091) BUN. There was a tendency (quadratic, P = 0.051) in fecal DM with pigs fed the moderate feed-grade AA diet having the lowest fecal DM. Pigs fed the diet containing DAP had increased (P = 0.005) fecal DM compared with pigs fed the high feed-grade AA diet. There was a tendency for an increase (P = 0.060) in the ATTD of DM for pigs fed the DAP diet compared with the pigs fed the high feed-grade AA diet. The ATTD of CP decreased (linear, P = 0.048) as the SID Lys:CP ratio increased. Pigs fed the diets containing either DAP or glycine had increased (P ≤ 0.026) CP digestibility compared with pigs fed the high feed-grade AA diet. These data suggest that diets for 25 to 50 lb pigs should be formulated to a SID Lys:CP ratio of 6.5 or lower and that adding a non-protein nitrogen source or non-essential AA to diets formulated above this ratio can improve feed efficiency and CP digestibility

Factors associated with dental visit and barriers to utilisation of oral health care services in a sample of antenatal mothers in Hospital Universiti Sains Malaysia

<p>Abstract</p> <p>Background</p> <p>The aims of this study were to determine factors associated with dental visit and to describe barriers to utilisation of oral health care services among antenatal mothers attending the Obstetric and Gynaecology Specialist clinic in Hospital Universiti Sains Malaysia.</p> <p>Methods</p> <p>A structured, self-administered questionnaire was used obtain information on the variables of interest pertaining to the current pregnancy from 124 antenatal mothers.</p> <p>Results</p> <p>The majority of the mothers claimed that their oral health status was good (67.0%) or very good (2.4%). On the contrary, most of them admitted of having had at least one oral health problem (59.7%) including cavitated (43.5%) and painful teeth (15.3%), bleeding gum (21.0%), and bad breath (10.5%). However, only 29% of the mothers visited dentist during the current pregnancy. Factors associated with the mothers' dental visit were exposure to oral health education before the pregnancy and awareness of relationship between poor maternal oral health and adverse pregnancy outcomes with odds ratio of 4.06 (95% CI: 1.67-9.78) and 3.57 (95% CI: 1.30-9.77) respectively. Common excuses given by most mothers include perceptions of not having any oral health problems (65.9%), long waiting time at the clinic (71.6%), and no immediate treatment given by the dentist (64.8%).</p> <p>Conclusions</p> <p>Utilisation of oral health care services among antenatal mothers was low. Mothers who reported dental visit were more likely to be those who had received oral health education before the current pregnancy and knew of the association between poor maternal oral health and adverse pregnancy outcomes. Dissatisfaction with the services rendered and perceptions of not having any oral health problems were the main barriers.</p

Mechanisms of growth inhibition of Phytomonas serpens by the alkaloids tomatine and tomatidine

Phytomonas serpens are flagellates in the family Trypanosomatidae that parasitise the tomato plant (Solanum lycopersicum L.), which results in fruits with low commercial value. The tomato glycoalkaloid tomatine and its aglycone tomatidine inhibit the growth of P. serpens in axenic cultures. Tomatine, like many other saponins, induces permeabilisation of the cell membrane and a loss of cell content, including the cytosolic enzyme pyruvate kinase. In contrast, tomatidine does not cause permeabilisation of membranes, but instead provokes morphological changes, including vacuolisation. Phytomonas treated with tomatidine show an increased accumulation of labelled neutral lipids (BODYPY-palmitic), a notable decrease in the amount of C24-alkylated sterols and an increase in zymosterol content. These results are consistent with the inhibition of 24-sterol methyltransferase (SMT), which is an important enzyme that is responsible for the methylation of sterols at the 24 position. We propose that the main target of tomatidine is the sterols biosynthetic pathway, specifically, inhibition of the 24-SMT. Altogether, the results obtained in the present paper suggest a more general effect of alkaloids in trypanosomatids, which opens potential therapeutic possibilities for the treatment of the diseases caused by these pathogens

Reduced Expression of the Vesicular Acetylcholine Transporter and Neurotransmitter Content Affects Synaptic Vesicle Distribution and Shape in Mouse Neuromuscular Junction

In vertebrates, nerve muscle communication is mediated by the release of the neurotransmitter acetylcholine packed inside synaptic vesicles by a specific vesicular acetylcholine transporter (VAChT). Here we used a mouse model (VAChT KDHOM) with 70% reduction in the expression of VAChT to investigate the morphological and functional consequences of a decreased acetylcholine uptake and release in neuromuscular synapses. Upon hypertonic stimulation, VAChT KDHOM mice presented a reduction in the amplitude and frequency of miniature endplate potentials, FM 1-43 staining intensity, total number of synaptic vesicles and altered distribution of vesicles within the synaptic terminal. In contrast, under electrical stimulation or no stimulation, VAChT KDHOM neuromuscular junctions did not differ from WT on total number of vesicles but showed altered distribution. Additionally, motor nerve terminals in VAChT KDHOM exhibited small and flattened synaptic vesicles similar to that observed in WT mice treated with vesamicol that blocks acetylcholine uptake. Based on these results, we propose that decreased VAChT levels affect synaptic vesicle biogenesis and distribution whereas a lower ACh content affects vesicles shape