277. Equine chorionic gonadotrophin isoform composition in commercial products compared with isoform composition in pregnant mare plasma

2008 ◽  
Vol 20 (9) ◽  
pp. 77
Author(s):  
U. A. Ciller ◽  
I. M. Ciller ◽  
J. R. McFarlane

It is well documented that there is considerable batch to batch variation in the activity of commercial preparations of gonadotrophins. These products are used in a variety of assisted reproductive procedures in the livestock industry, consequently this high degree of variation between products and batches adds to the already considerable between animal variations in response to the treatment. Equine chorionic gonadotrophin (eCG) is a heterodimeric glycoprotein hormone secreted by the placental endometrial cups during the first third of gestation in the horse. Plasma is harvested from pregnant mares between 40–90 days of gestation and the eCG isolated and used to formulate commercial preparations. Previous research has shown that eCG like the other gonadotrophins is a highly heterogeneous molecule with significant differences in bioactivity between isoforms. The aim of this study was to determine whether significant differences in isoform composition exist between various commercial preparations of eCG (n = 15), and how this compares with the isoform composition found in plasma (n = 23). Concentrations of eCG were determined using a competitive eCG ELISA. Liquid phase iso-electric focusing was used to fractionate plasma and the commercial preparations into 10 pH ranges from pH 3.0 to pH 10.0. Data from the 10 fractions were grouped into acidic (pH 3.0–5.1), intermediate (pH 5.2–7.9), or basic (pH 8.0–10.0) isoform categories for analysis. Immunoactivity between commercial eCG products ranged from 44% to 362% of stated bioactivity. Iso-electric focusing showed that the majority of the immunoactivity (92%) of the commercial preparations was found in the acidic fractions (pH 3.0–5.1), and in particular in the pH range 3.0–3.8. This contrasted starkly with isoform profiles found in pregnant mare plasma samples which showed a much greater spread across all 3 pH ranges. In summary, the isolation processes of commercial eCG preparations appears to selectively favour the acidic isoforms of eCG.

1990 ◽  
Vol 2 (2) ◽  
pp. 137 ◽  
Author(s):  
HG Burger ◽  
SC Tiu ◽  
ML Bangah ◽  
Kretser DM de

Inhibin is a gonadal glycoprotein hormone involved in the regulation of FSH. To elucidate the regulation of inhibin production we investigated the acute (daily for 1 week) and chronic (9-10 months of follow-up) changes in immunoreactive inhibin, testosterone, LH and FSH levels in the serum of three hypogonadotrophic hypogonadal patients treated first with hCG alone (for 3-6 months) and then hCG combined with FSH (1-5 months). One patient was unexpectedly resistant to gonadotrophin therapy; in the other two, hCG, with or without FSH, caused a rise in inhibin and testosterone, supporting previous observations that LH, as well as FSH, plays a role in the regulation of inhibin or inhibin-related peptides in men.


1981 ◽  
Vol 97 (2) ◽  
pp. 166-175 ◽  
Author(s):  
F. Strollo ◽  
J. Harlin ◽  
H. Hernandez-Montes ◽  
D. M. Robertson ◽  
A. A. Zaidi ◽  
...  

Abstract. A single bolus of 100 μg of gonadoliberin (LRH) was administered intravenously to 8 post-menopausal and 9 normally menstruating women and blood was withdrawn before and 30, 60, 120 and 240 min after LRH stimulation. The plasma samples obtained at different time intervals from women showing a sufficiently high response to LRH (menopausal: 8, menstruating: 3) were combined and 2 ml samples of each pool were fractionated in triplicate by electrofocusing on sucrose density gradient. In addition, two plasma pools, obtained 30 min following LRH stimulation, one from 4 normally menstruating women (exhibiting a relatively low LH-response) and the other from 2 normally menstruating women aged 40, were analyzed in the same way in duplicate electrofocusing experiments. The hLH activity was determined in each electrofocusing fraction by an in vitro bioassay method following elution and purification by gel filtration. The LH activity was distributed as four major peaks at pI values of 7.10 ± 0.05, 7.58 ± 0.06, 8.10 ± 0.04 and 8.54 ± 0.05 and a broad area of activity comprising a number of peaks in the pH range of 8.69–9.50. The analysis of the data revealed marked differences in the relative distribution of the various molecular species present in the blood of menopausal women and of normally menstruating women. A molecular species exhibiting a pI value of 7.10 was invariably present (10 – 15% of the total) in all samples of post-menopausal plasma (PMP) but was consistently absent from all samples of midcycle plasma (MCP). The amount of relatively 'less alkaline' material (eluted from pH range 7.37–8.32) was significantly higher (P < 0.001) in the PMP samples compared to MCP samples. On the other hand, in the MCP samples the amount of relatively 'more alkaline' material eluted from the pH range 8.33–9.50 was significantly (P < 0.001) higher (about 60% of the total recovered activity) compared to the PMP samples (about 30% of the total). Following LRH stimulation significant temporal changes were observed in the relative contribution of various molecular species to the hLH profile. A gradual increase, up to 60 min, in the material eluted in the pH range 6.87–7.36 in the post-menopausal plasma samples was accompanied by a gradual decrease in the material eluted in the pH range 7.84–8.32. Two hours after LRH stimulation a significant drop was found in the material collected from pH range 8.33–8.68, with a concomitant rise in the material eluted in the pH range 8.69–9.50. This last mentioned shift was also observed in the plasma of normally menstruating women. It is concluded that major differences exist in the composition of biologically active hLH species present in the peripheral blood of post-menopausal and normally menstruating women. Moreover, significant temporal changes occur in the composition of circulating hLH species following stimulation by LRH both in post-menopausal and in normally menstruating women.


1973 ◽  
Vol 8 (1) ◽  
pp. 110-121
Author(s):  
A. Netzer ◽  
J.D. Norman

Abstract The merits of activated carbon for removal of organic compounds from wastewater have been well documented in the literature. On the other hand there is a lack of published data on the use of activated carbon for the removal of trace metals from wastewater. Experiments were designed to assess the possibility that activated carbon treatment would remove aluminum, cadmium, chromium, cobalt, copper, iron, lead, manganese, mercury, nickel, silver and zinc from wastewater. All metals studied were tested over the pH range 3-11. Greater than 99.5% removal was achieved by pH adjustment and activated carbon treatment for most of the metals tested.


1980 ◽  
Vol 45 (4) ◽  
pp. 1144-1154 ◽  
Author(s):  
Miroslav Baudyš ◽  
Helena Keilová ◽  
Vladimír Kostka

To determine the primary structure of the C-terminal part of the molecule of chicken pepsinogen the tryptic, chymotryptic and thermolytic digest of the protein were investigated and peptides derived from this region were sought. These peptides permitted the following 21-residue C-terminal sequence to be determined: ...Ile-Arg-Glu-Tyr-Tyr-Val-Ile-Phe-Asp-Arg-Ala-Asn-Asn-Lys-Val-Gly-Leu-Ser-Pro-Leu-Ser.COOH. A comparison of this structure with the C-terminal sequential regions of the other acid proteases shows a high degree of homology between chicken pepsinogen and these proteases (e.g., the degree of homology with respect to hog pepsinogen and calf prochymosin is about 66%). Additional tryptic peptides, derived from the N-terminal part of the zymogen molecule whose amino acid sequence has been reported before, were also obtained in this study. This sequence was extended by two residues using an overlapping peptide. An ancillary result of this study was the isolation of tryptic peptides derived from other regions of the zymogen molecule.


1992 ◽  
Vol 57 (11) ◽  
pp. 2302-2308
Author(s):  
Karel Mocek ◽  
Erich Lippert ◽  
Emerich Erdös

The kinetics of the reaction of solid sodium carbonate with sulfur dioxide depends on the microstructure of the solid, which in turn is affected by the way and conditions of its preparation. The active form, analogous to that obtained by thermal decomposition of NaHCO3, emerges from the dehydration of Na2CO3 . 10 H2O in a vacuum or its weathering in air at room temperature. The two active forms are porous and have approximately the same specific surface area. Partial hydration of the active Na2CO3 in air at room temperature followed by thermal dehydration does not bring about a significant decrease in reactivity. On the other hand, if the preparation of anhydrous Na2CO3 involves, partly or completely, the liquid phase, the reactivity of the product is substantially lower.


2016 ◽  
Vol 397 (2) ◽  
pp. 135-145 ◽  
Author(s):  
Miriam Olombrada ◽  
Lucía García-Ortega ◽  
Javier Lacadena ◽  
Mercedes Oñaderra ◽  
José G. Gavilanes ◽  
...  

Abstract Ribotoxins are cytotoxic members of the family of fungal extracellular ribonucleases best represented by RNase T1. They share a high degree of sequence identity and a common structural fold, including the geometric arrangement of their active sites. However, ribotoxins are larger, with a well-defined N-terminal β-hairpin, and display longer and positively charged unstructured loops. These structural differences account for their cytotoxic properties. Unexpectedly, the discovery of hirsutellin A (HtA), a ribotoxin produced by the invertebrate pathogen Hirsutella thompsonii, showed how it was possible to accommodate these features into a shorter amino acid sequence. Examination of HtA N-terminal β-hairpin reveals differences in terms of length, charge, and spatial distribution. Consequently, four different HtA mutants were prepared and characterized. One of them was the result of deleting this hairpin [Δ(8-15)] while the other three affected single Lys residues in its close spatial proximity (K115E, K118E, and K123E). The results obtained support the general conclusion that HtA active site would show a high degree of plasticity, being able to accommodate electrostatic and structural changes not suitable for the other previously known larger ribotoxins, as the variants described here only presented small differences in terms of ribonucleolytic activity and cytotoxicity against cultured insect cells.


The work described in this and the following paper is a continuation of that in parts I and II, devoted to elucidation of the mechanism of the reactions of methylene with chloroalkanes, with particular reference to the reactivities of singlet and triplet methylene in abstraction and insertion processes. The products of the reaction between methylene, prepared by the photolysis of ketene, and 1-chloropropane have been identified and estimated and their dependence on reactant pressures, photolysing wavelength and presence of foreign gases (oxygen and carbon mon­oxide) has been investigated. Both insertion and abstraction mechanisms contribute significantly to the over-all reaction, insertion being relatively much more important than with chloroethane. This type of process appears to be confined to singlet methylene. If, as seems likely, there is no insertion into C—Cl bonds under our conditions (see part IV), insertion into C2—H and C3—H bonds occurs in statistical ratio, approximately. On the other hand, the chlorine substituent reduces the probability of insertion into C—H bonds in its vicinity. As in the chloroethane system, both species of methylene show a high degree of selectivity in their abstraction reactions. We find that k S Cl / k S H >7.7, k T Cl / k T H < 0.14, where the k ’s are rate constants for abstraction, and the super- and subscripts indicate the species of methylene and the type of atom abstracted, respectively. Triplet methylene is discriminating in hydrogen abstraction from 1-C 3 H 7 Cl, the overall rates for atoms attached to C1, C2, C3 being in the ratios 2.63:1:0.


1931 ◽  
Vol 53 (4) ◽  
pp. 535-552 ◽  
Author(s):  
Leslie T. Webster ◽  
Thomas P. Hughes

1. Pneumococci were obtained at one time or another from the nasal passages or throats of 80 per cent of 105 adults and children studied. In adults, they were obtained more frequently from the throat; in children, as often from the nasal passages as from the throat. 2. Of 500 pneumococcus strains studied, 97 per cent proved to be serologically specific. They formed smooth colonies and were for the most part avirulent for mice. Types I and II were obtained from one and two individuals respectively on one occasion only. Type III was obtained from nine individuals; Type XIII from nine individuals; Type XVI and Type XVIII from three individuals, for varying periods in each case. Atypical pneumococci were secured from 13 persons on single and scattered occasions. They varied in colony morphology, did not kill mice, or agglutinate in saline, but flocculated in all types of antipneumococcus sera employed and over a wide pH range in acid buffers. Their occurrence was apparently not associated with any type-transformation or virulence-enhancement process in vivo. 3. Strains of pneumococcus obtained on successive cultures from a given carrier were, with rare exceptions, of the same serological type and were similar in colony morphology, virulence for mice, and other tested biological characteristics. 4. Pneumococci of Types I and II were obtained under conditions suggestive that they lacked a capacity to spread readily; pneumococci of Types III and XIII, on the other hand, were obtained under conditions suggestive that they were spreading from person to person. 5. The persons studied differed consistently with respect to the occurrence of pneumococci. Some were pneumococcus-free, some were transient carriers, some periodic, and some chronic carriers. Data are given which suggest that the differences were due to variations in host resistance. 6. The incidence of pneumococci in all individuals studied underwent a seasonal variation paralleling that of coryza and sore throats in the same persons.


2004 ◽  
Vol 55 (8) ◽  
pp. 635-640 ◽  
Author(s):  
Kenji Yoshino ◽  
Kentaro Sakai ◽  
Yoko Mizuha ◽  
Ayako Shimizuike ◽  
Shigeru Yamamoto

PEDIATRICS ◽  
1964 ◽  
Vol 34 (5) ◽  
pp. 705-707
Author(s):  
WILLIAM D. DONALD

In vitro sensitivities of 70 shigella strains isolated over a recent 18-month period are reported. The high degree of sulfadiazine resistance casts some doubt on the selection of this agent as the drug of choice in the treatment of shigellosis, at least in this community. Some of the other agents, although inhibiting the growth of the organisms in vitro, have disadvantages such as toxicity or failure of absorption from the gastrointestinal tract. Tetracycline resistance was found in only 7% of the organisms tested, but from this and other reports we may anticipate the occurrence of more organisms resistant to this agent. The results of the sensitivities to ampicillin are encouraging and further studies including clinical trials of this agent are in order.


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