Studies on the anti-tumor efficacy of systemically administered recombinant tumor necrosis factor against several murine tumors in vivo

The anti-tumor activity of recombinant human tumor necrosis factor (rHTNF) was examined against four newly induced murine sarcomas (MCA-101, -102, -105, and -106) and a murine adenocarcinoma (MCA-38) transplanted s.c. into C57BL/6 mice. The serum half-life after a single i.v. injection of rHTNF was determined to be 30 +/- 2 min. Tumor-bearing mice were more susceptible to the toxic side effects of rHTNF than were normal mice. Forty-eight percent (41/86) of tumor bearing animals that received 10 micrograms rHTNF died within 48 hr after treatment compared with no deaths in 28 normal animals receiving this dose. Treatment of mice bearing either the MCA-101, -102, -105, or -106 sarcoma or the MCA-38 adenocarcinoma with rHTNF resulted in a marked necrosis of the central portion of each tumor within 24 hr. Animals bearing the weakly immunogenic tumors MCA-105, -106, and -38 experienced a reduction in average tumor area of 47% +/- 5, 46% +/- 6, and 37% +/- 11, respectively, by 3 to 4 days after treatment with rHTNF compared with pre-treatment values (p less than 0.001); increases of 79% +/- 11, 74% +/- 10, and 41% +/- 6 were seen in excipient-treated control animals over the same period. In contrast, animals bearing the non-immunogenic tumors MCA-101 and -102 experienced little if any decrease in tumor area at the doses of rHTNF used. rHTNF failed to mediate cures in animals bearing MCA-38, -101, or -102. In contrast, 67 and 28% of animals bearing MCA-105 and -106, respectively, which received 6 to 10 micrograms rHTNF were cured. Likewise, animals bearing MCA-105 and -106 sarcomas treated with 6 to 10 micrograms rHTNF had significantly increased survival compared with excipient-treated control animals. In contrast, no significant difference in mean survival was observed between excipient and rHTNF treated animals bearing MCA-38, -101, or -102. Histologically, the necrotic response of immunogenic MCA-106 and non-immunogenic MCA-102 tumors to systemically administered rHTNF was very similar. These two tumors differed morphologically, however, by the greater degree of chronic inflammation that was present at the periphery of the MCA-106 tumor in comparison with the MCA-102. By 72 hr after rHTNF administration, the sites of regressed MCA-106 tumors were replaced by a heterogeneous population of inflammatory cells and tumor cell "ghosts".(ABSTRACT TRUNCATED AT 400 WORDS)     

Hydrogen and aluminium tolerance

Summary Reduced productivity due to soil acidity has been demonstrated with subterranean clover and wheat in many parts of Australia. Nodulation in clover appears to be more sensitive to low pH than growth of the host plant in the presence of adequate mineral nitrogen. Low pH is associated with aluminium toxicity in a number of species and nodulation in clover is more sensitive than growth of the host plant to Al. Decrease in soil pH is associated with significant increases in exchangeable Al. The breeding of Al tolerant wheats in Australia involves a backcross programme utilizing the transfer of tolerance from the Brazilian cultivar Carazinho.     

Embryo transfer in fallow deer (Dama dama): superovulation, embryo recovery and laparoscopic transfer of fresh and cryopreserved embryos

Multiple ovulation-embryo transfer (MOET) protocols for farmed fallow deer (Dama dama ) were investigated in a series of 3 experiments. A total of 37 donors, of either European (D.d. dama ; n = 30) or Mesopotamian hybrid (D.d. mesopotamica x D.d. dama ; n =7) genotype, each received an intravaginal silastic device containing 0.3 g progesterone (CIDR((R))-type G device) for 14 d and injections of 0.5 units ovine FSH (8 x 0.06 unit injections from Days 10 to 14 of device insertion) and 100 IU PMSG (either with the first or last FSH injection). All donors received laparoscopic intrauterine inseminations of fresh semen (50 x 10(6) spermatozoa) from a Mesopotamian sire 36 h after withdrawal of CIDR((R)) devices. Embryos were recovered by laparotomy on Day 6 (Day 0 = estrus). Mean ovulation rates for the 3 experiments were 8.1, 9.8 and 7.0, with no effect of PMSG timing (P>0.10). However, embryo recovery rates, albeit low throughout the study (29.6%), were significantly improved with later PMSG administration (33.9 vs 20.1%; P<0.05). Hybrid and European donors performed in a similar manner. A range of embryo development stages was recovered throughout the study. In 2 experiments laparoscopic transfer of embryos to 48 recipient does treated previously with intravaginal CIDR((R)) devices for 14 d yielded a total pregnancy rate of 37.5%. In the experiment with fresh embryos, the use of clenbuterol to reduce uterine turgidity resulted in a higher proportion of does conceiving (3 4 ; 75%) compared with that of the untreated does (0 6 , 0%; P<0.05). In the second experiment, in which all the does routinely received clenbuterol, 10 19 (53%) and 5 19 (26%) does conceived following the transfer of fresh and cryopreserved embryos, respectively (P<0.05). While the overall efficiency of the MOET program was low (equivalent of 0.9 to 1.0 surrogate pregnancies per donor), improvements in the recovery rate of transferable embryos have considerable potential for genetic improvement of farm stock and captive propagation of endangered Mesopotamian fallow deer through maternal surrogacy programs.     

Use of GEOCHEM-PC to predict rare earth element (REE) species in nutrient solutions

The interpretation of results of some experiments examining effects of rare earth elements (REE) on plant growth may have been complicated by rare earth phosphate precipitation. Simulations were undertaken using the computer model GEOCHEM-PC to define REE solubility limits and predict REE species in low and high ionic strength nutrient solutions. In low ionic strength solutions containing 5 M P, lanthanum phosphate (LaPO₄) precipitation is predicted to occur at solution pH>4.0, reaching a maximum (>95% of total) at pH 5.5. In high ionic strength solutions (1000 M P) over 95% of the La is predicted to precipitate as phosphate at pH>4.0. The predicted behaviour of cerium (Ce) was closely similar to that for La.At pH 5.5, the concentration of REE species in solution can be increased only after virtually all the P has been precipitated. Consequently, it is important to consider REE-P interactions in nutrient solutions when investigating REE effects on plant growth.     

Effect of progesterone and oestradiol benzoate on oestrous behaviour and secretion of luteinizing hormone in ovariectomized fallow deer (Dama dama).

Eighteen ovariectomized fallow deer does and two adult bucks were used to investigate the effect of exogenous progesterone and oestradiol benzoate on oestrous behaviour and secretion of luteinizing hormone (LH). In Expts 1 and 2, conducted during the breeding season (April-September), does were treated with intravaginal Controlled Internal Drug Release (CIDR) devices (0.3 g progesterone per device) for 12 days and differing doses of oestradiol benzoate administered 24 h after removal of the CIDR device. The dose had a significant effect on the proportion of does that exhibited oestrus within the breeding season (P less than 0.001), the incidence of oestrus being 100% with 1.0, 0.1 and 0.05 mg, 42% for 0.01 mg and 0% for 0.002 mg oestradiol benzoate. There was a significant log-linear effect of dose on the log duration of oestrus, which was 6-20, 2-14, 2-12 and 2 h after treatment with 1, 0.1, 0.05 and 0.01 mg of oestradiol benzoate, respectively. Dose had a significant effect on the peak plasma LH concentration (P less than 0.01), mean (+/- s.e.m.) surge peaks of 27.7 +/- 2.3, 25.9 +/- 1.8 and 18.6 +/- 3.4 ng/ml being observed following treatment with 1, 0.1 and 0.01 mg oestradiol benzoate respectively. In Expt 3, also conducted during the breeding season, progesterone treatment (0 vs. 6-12 days) before the administration of 0.05 mg oestradiol benzoate had a significant effect on the incidence of oestrus (0/6 vs. 10/12, P less than 0.05), but not on LH secretion. The duration of progesterone treatment (6 vs. 12 days) had no effect on oestrus.(ABSTRACT TRUNCATED AT 250 WORDS)     

Seasonal pattern of LH and testosterone secretion in adult male fallow deer, Dama dama

At monthly intervals during the year blood samples were collected every 20 min for 12 h from 4 entire and 2 prepubertally castrated adult fallow deer bucks. In the entire bucks there were seasonal changes in mean concentrations and pulse frequencies of plasma LH. Mean concentrations in late summer and autumn were 3-6 times higher than during other seasons. LH pulse frequency was low (0-1 pulses/12 h) during most of the year and increased only during the 2-month period (January and February) that marked the transition from the non-breeding season to the autumn rut. During this period there was a close temporal relationship between pulses of LH and testosterone. However, during the rutting period (March and April) episodic secretion of testosterone, manifest as surges in plasma concentrations of 4-6 h duration, was not associated with any detectable pulses in LH although mean plasma concentrations of LH remained elevated. During the rut, the surges of plasma testosterone occurred at similar times of the day. Plasma profiles in May indicated very low concentrations of LH and testosterone secretion in the immediate post-rut period. Castrated bucks exhibited highly seasonal patterns of LH secretion, with mean plasma LH concentrations and LH pulse frequency being lowest in November (early summer) and highest in February and March (late summer-early autumn). Mean concentrations and pulse frequency of LH in castrated bucks were higher than for entire bucks at all times of the year.     

Novel class of nuclear genes involved in both mRNA splicing and protein synthesis in Saccharomyces cerevisiae mitochondria

Summary We have cloned three distinct nuclear genes, NAM1, NAM7, and NAM8, which alleviate mitochondrial intron mutations of the cytochrome b and COXI (subunit I of cytochrome oxidase) genes when present on multicopy plasmids. These nuclear genes show no sequence homology to each other and are localized on different chromosomes: NAM1 on chromosome IV, NAM7 on chromosome XIII and NAM8 on chromosome VIII. Sequence analysis of the NAM1 gene shows that it encodes a protein of 440 amino acids with a typical presequence that would target the protein to the mitochondrial matrix. Inactivation of the NAM1 gene by gene transplacement leads to a dramatic reduction of the overall synthesis of mitochondrial protein, and a complete absence of the COXI protein which is the result of a specific block in COXI pre-mRNA splicing. The possible mechanisms by which the NAM1 gene product may function are discussed.     

Resonance Raman examination of axial ligand bonding and spin-state equilibria in metmyoglobin hydroxide and other heme derivatives

Resonance Raman spectra and excitation profiles have been obtained within the 5700-6300-A absorption band of purified sperm whale metmyoglobin hydroxide (MbIIIOH) solutions. A large enhancement occurs for a Raman peak at 490 cm-1 which is shown by isotopic substitution of 18O for 16O to be almost purely an Fe-O stretch. The Fe-O vibration in MbIIIOH occurs 5 cm-1 to lower energy than the corresponding vibration at 495 cm-1 in human methemoglobin hydroxide (HbIIIOH) [Asher, S., Vickery, L., Schuster, T., & Sauer, K. (1977) Biochemistry 16, 5849], reflecting differences in ligand bonding between Mb(III) and Hb(III). A larger frequency difference (10 cm-1) exists between MbIIIF and HbIIIF for the Fe-F stretch. We do not observe separate Fe-O or Fe-F stretches from the alpha and beta chains of either HbIIIOH or HbIIIF. Excitation profile measurements for MbIIOH indicate that the 5700-6300-A absorption band is composed of two separate absorption bands which result from a high- and a low-spin form of MbIIIOH. The spin-state-sensitive Raman band at 1608 cm-1 reflects the high-spin species and has an excitation profile maximum at about 6000 A while the low-spin Raman band occurs at 1644 cm-1 and shows an excitation profile maximum at 5800 A. The Fe-O stretch at 490 cm-1 has an excitation profile maximum at about 6000 A. The differences in frequency and Raman cross section between the Fe-X vibrations in MbIIIX and HbIIIX (X = OH-, F-) can be related to increases in the out-of-plane iron distance for the high-spin species of MbIIIX. The shift in the 1644-cm-1 MbIIIOH low-spin state Raman band indicative of the heme core size to 1636 cm-1 in HbIIIOH indicates a larger heme core size in HbIIIOH. Raman frequency shifts are used to estimate differences in bond strain energies between MbIIIX and HbIIIX (X = OH-, F-). Previous resonance Raman excitation profile data can be interpreted in terms of separate contributions from different spin-state species.     

A phylogenetic estimate for golden moles (Mammalia,Afrotheria, Chrysochloridae)

Background  

Golden moles (Chrysochloridae) are small, subterranean, afrotherian mammals from South Africa and neighboring regions. Of the 21 species now recognized, some (e.g., Chrysochloris asiatica, Amblysomus hottentotus) are relatively common, whereas others (e.g., species of Chrysospalax, Cryptochloris, Neamblysomus) are rare and endangered. Here, we use a combined analysis of partial sequences of the nuclear GHR gene and morphological characters to derive a phylogeny of species in the family Chrysochloridae.