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The land-based culture of greenhip abalone Haliotis laevigata in southeastern Australia is carried out using seawater that is prone to seasonal temperature fluctuations and is done almost exclusively using artificial feeds. Although some nutrition research has been done to identify the optimum dietary protein level, typically farms use only I diet for grow-out after the juveniles are weaned. Little consideration has been given to the effects of fluctuating water temperatures and dietary protein levels on the morphology of the gastrointestinal tract (GIT) of abalone. Because these factors are known to impact growth in other aquatic species, it is important that they are investigated further to improve growth in abalone species. In this study, the histological changes of the GIT of greenlip abalone in response to 2 water temperatures and 4 dietary levels of crude protein (juvenile, 27% and 36%; subadult, 24% and 33%) for juveniles (1.75 g) and subadults (22.93 g) were investigated. The epithelial thickness of the stomach and crop; intestinal villus height, width, and area; lamina propria height; and stomach, crop, and intestinal neutral and acidic goblet cell numbers were measured. The stomach epithelium was significantly thicker at 14°C than 22°C in both juveniles and subadults, whereas the crop epithelium was significantly thicker at 22°C than 14°C in juveniles. The crop epithelial thickness of subadults was reduced by increasing dietary protein; however, juveniles did not show the same response. Juvenile abalone were more sensitive to temperature fluctuations than subadults, whereas significant effects of dietary protein levels were only observed in subadults. The alterations in the morphology of the GIT did not appear to be detrimental to the health and growth of the abalone. Further research is required to investigate the interactive effects of water temperature and dietary ingredients, particularly in regard to antinutritional factors, on the morphology and function of the GIT to improve our understanding of abalone physiology. [ABSTRACT FROM AUTHOR]

Mitsubishi's MD-805, a potent and selective inhibitor of thrombin which contains four stereogenic centers, has been the starting point for an optimization program. A systematic synthetic study resulted in thrombin inhibitors achiral at P2 and P3 but with a 10-fold increase in potency over the original lead. A number of 4-substituted piperidines were synthesized and examined as replacements for 2-carboxy-4-methylpiperidine at P2; 4-fluoroethylpiperidine (FEP) among others provided inhibitors (e.g. 45g) of increased potency. An enantioselective route was developed to 3(R)-methyl-1,2,3,4-tetrahydroquinolinesulfonyl chloride. Inhibitors containing this enantiomerically pure P3 (42d) had similar potency to the racemic material and provided support, with modeling studies, for the preparation of the gem 3,3-disubstituted compounds. A series of inhibitors containing the novel 3,3-dimethyl-1,2,3,4-tetrahydroquinolinesulfonyl (DMTHQS) P3 (Table 5) were synthesized and showed a similar activity profile as the monomethyl series. The combination of P3-DMTHQS, P2-FEP, and P1-arginine (45g) had a Ki of 6 nM (MD-805 Ki = 85 nM). In animal models of both venous and arterial thrombosis, one inhibitor (42e) was shown to produce a dose-dependent inhibition of thrombus formation that in some situations was superior to that of MD-805.

The optimal conditions for opening of stomata in detached epidermis of the Crassulacean Acid Metabolism (CAM) plant Kalanchoe daigremontiana were determined. Stomatal opening in CO2-free air was unaffected by light so subsequently all epidermal strips were incubated in the dark and in CO2-free air. Apertures were maximal after 3 h incubation and were significantly greater at 15° C than 25° C. Thus stomata in isolated epidermis of this species can respond directly to temperature. Stomatal opening was greatest when the incubating buffer contained 17.6 mol m-3 K+, but decreased linearly with increasing K+ concentrations between 17.6 and 300 mol m-3; the decrease in aperture was shown to be associated with increasing osmotic potentials of the solutions. Reasons for this behaviour, which differs from that of many C3 and C4 species, are discussed. Stomatal apertures declined linearly upon incubation of epidermis on buffer solutions containing between 10-11 and 10-5 mol m-3 abscisic acid (ABA). Hence stomata on isolated epidermis of K. daigremontiana respond to lower concentrations of ABA than those of any species reported previously.

Objective To evaluate transcervical amnioinfusion for meconium stained amniotic fluid during labout.

We have tested whether an animal with substantial amounts of both IGF-I and IGF-II in circulation, such as the guinea pig, would respond to chronic IGF infusion in the same manner as the adult rat, which has negligible amounts of IGF-II in blood. Female guinea pigs of 350 g body weight were continuously infused for 7 days with recombinant guinea pig IGF-I or -II (120 or 360 μg/day) or long R3IGF-I (LR3IGF-I) (120 μg/day), an analogue which has much reduced affinities for IGF binding proteins. IGF-I or IGF-II infusion led to substantial increases in plasma IGF-I or IGF-II respectively in comparison with vehicle-infused animals. Nevertheless, body weight gain, feed intake, feed conversion efficiency and carcass composition were not significantly affected by any treatment (significance was deemed to be P<0·05). Amongst the tissues examined only the fractional weight (g/kg body weight) of the adrenals was increased, and that only by the higher dose (360 μg/day) of IGF-I. However, the fractional weight of adrenals, gut, kidneys and spleen were significantly increased by LR3IGF-I, but again overall growth was not stimulated. A possible explanation for the lack of IGF-I effects is that total circulating IGF concentrations were not increased by these treatments. IGF-II significantly raised total IGF concentrations at the higher dose only. Plasma IGF-I was reduced by IGF-II infusion, as was plasma IGF-II by IGF-I infusion. LR3IGF-I treatment lowered both plasma IGF-I and IGF-II concentrations, a response probably related to a reduction in total plasma IGF binding protein (IGFBP), especially IGFBP-3, concentrations. We conclude that although the guinea pig is responsive to IGF treatment, the effects differ markedly from those elicited in rats.Journal of Endocrinology(1995) 146,247–253

Howarth GS, Fraser R, Frisby CL, Schirmer MB, Yeoh EK. Effects of insulin-like growth factor-I administration on radiation enteritis in rats, Scand J Gastroenterol 1997; 32:1118-1124.Background: Acute radiation-induced damage to the small bowel occurs frequently during abdominal radiotherapy. Since the small intestine is selectively responsive to the growth-promoting effects of insulinlike growth factor-I (IGF-I), we investigated the effects of IGF-I administration on mucosal recovery from radiation enteritis in the rat. Methods: Rats received a single 10-Gy dose of total abdominal irradiation followed by implantation of mini-pumps infusing either IGF-I or vehicle for 4 days. After the rats had been killed, gut organs were weighed before light microscopic and biochemical examination. Results: Irradiated rats receiving IGF-I lost less body weight than vehicle-treated rats, whereas the wet weights of the stomach, small intestine, and colon were increased by 10%, 19%, and 21%, respectively, and crypt depth was increased in the duodenum, jejunum, and ileum. Conclusions: IGF-I administration after abdominal irradiation increased small-intestinal mass and improved indicators of mucosal integrity, suggesting acceleration of small-intestinal mucosal recovery from radiation injury.

The potential of medicine to intervene to prolong or shorten the life of those considered to be dying or of those whose life is rated as of little or even negative value has only recently surfaced. It is an issue likely to affect society and the normative social relationships which that society believes it is duty to promote. It is probable that, covertly, members of the medical profession have long played a role in speeding up the process of dying, with or without the consent of affected individuals. The openness, however, with which the moral issues involved in hastening or prolonging life by medical means are now discussed is a late 20th century phenomenon. Sociologists are beginning to study the circumstances surrounding the issues and the wider societal implications of possible changes in the law, professional practices and normative values. Their work may well begin to influence public policy as well as private practice.

Gut Zn homeostatic responses to low, replete, and excess dietary Zn (10, 150, and 400 mg Zn/kg, respectively) were compared in mice with (MT+/+) and without (MT−/−) metallothionein (MT) expression. MT concentrations decreased progressively from stomach (12.9 nmol Cd bound/g) to colon (4.6 nmol Cd bound/g). Small intestinal MT was increased in mice fed the 400-mg Zn/kg diet (+130%, duodenum; +56%, jejunum; +29%, terminal ileum), but not in the stomach, cecum and colon. Zn concentrations were much higher in the distal gut at increasing Zn intakes in MT+/+ mice but to a lesser extent in MT−/− mice. On the 10-mg Zn/kg diet, MT−/− mice had 45% more Zn in the jejunum/ileum than MT+/+ mice. In fasted (20 h) mice, Zn concentrations in all gut regions were similar to those of MT+/+ mice fed the 10-mg Zn/kg diet, irrespective of prior Zn intake or genotype. Liver MT quadrupled in mice fasted after the 10-mg Zn/kg diet but only doubled after the 400-mg Zn/kg diet, a trend also present in gut MT. Glucagon administration stimulated gut as well as liver MT, implicating it as a major component of the MT response to fasting. MT−/− mice had five times more variation than MT+/+ mice in plasma Zn over all dietary groups. Together, these findings demonstrate that without MT, there is little modification of regional gut Zn concentrations in response to extremes of dietary Zn and poorer regulation of Zn homeostasis.

The effects of continuous 14 day infusion of recombinant human IGF-I (104 or 260 μg/day) or IGF-II (104, 260 or 650 μg/day) via s.c. implanted osmotic pumps were compared in young female rats in order to establish the relative efficacies of these two growth factors.Significant increases in body weight gain and feed conversion efficiency were achieved by 260 of IGF-I or 650 μg/day of IGF-II. These treatments were associated with increased nitrogen retention and increases in the fractional weights of kidneys, spleen, total gut and individual gut regions. There was an increase in the size of villi and muscularis lining the jejunum, suggesting an increased absorptive capacity of the gut. However there was no significant change in the amount of faecal nitrogen excretion when expressed as a percentage of nitrogen intake. Interestingly, IGF-II was at least as potent as IGF-I in increasing the depth of jejunal crypts. Infusion of equivalent doses of either IGF-I or IGF-II resulted in similar increases in circulating concentrations of the respective peptides, though IGF-II infusion dosedependently decreased plasma IGF-I concentrations from those of the controls. Plasma IGF-binding protein levels were increased by both IGF-I and IGF-II treatments, though IGF-I elicited greater responses.In summary, IGF-II can promote the growth of young female rats, although generally less potently than IGF-I.Journal of Endocrinology(1995) 144,91–98

The effects of insulin-like growth factor-I (IGF-I) on the gut of 150 g dexamethasone-treated rats were compared with those of two analogues with reduced affinity for IGF-binding proteins, des(1–3)IGF-I and LR3IGF-I, an N-terminal-extended variant. Administration of IGF-I for 7 days to rats made catabolic by co-treatment with dexamethasone induced a dose-dependent increase in total gut weight, with the highest dose of IGF-I (695 μg/day) increasing gut weight by up to 60%, and gut weight as a fraction of body weight by up to 32%. Effects were apparent in all regions of the gut examined, including the stomach, small intestine and colon. Histological and biochemical analyses of the intestine showed that cross-sectional mass, rather than gut length, was increased, and proportional increases in wet weight, protein and DNA content per unit length were measured in both the mucosa and muscularis layers. The rate of duodenal protein synthesis measured on day 7 of treatment was not increased by IGF-I treatment. The IGF-I analogues had qualitatively similar effects to IGF-I, but were consistently severalfold more potent, providing evidence that IGF-binding proteins reduce the biological activity of exogenous IGF-I in the gut. The results indicate that the gut is one of the most sensitive IGF-I target tissues, and that potency in vivocorrelates with a reduced interaction with IGF-binding proteins.Journal of Endocrinology(1992) 133,421–431

The prediction and subsequent prevention of errors, which are an integral element of human behaviour, require an understanding of their cause. The incident monitoring technique was developed in the study of aviation errors in the Second World War and has been applied more recently in the field of anaesthetics. This pilot study represents one of the first attempts to apply the incident monitoring technique in the general practice environment.

The preparation of 8-deoxy-1,2:3,4-di-O-isopropylidene-D-erythro-α-D-galacto-octopyranose (2) from two octenoses is described. The structure of 2was established by degradation of its di-O-methyl derivative to 1-deoxy-2,3-di-O-methyl-L-erythritol. This work permits the assignment of configuration to the octenoses. Acid-catalyzed hydrolysis of 2gave a new higher-carbon sugar, 8-deoxy-D-erythro-D-galacto-octose (4). The synthesis of 1-deoxy-2,3-di-O-methyl-L-threitol and 1-deoxy-2,3-di-O-methyl-D-erythritol is reported.

The preparation of 6-deoxy-3-C-methyl-2-O-methyl-D-allose is described. The compound was compared with L-vinelose, a new branched-chain sugar with the same constitution recently isolated, bound to cytidine 5′-pyrophosphate, from Azotobactervinelandiistrain O; the two sugars were shown to differ in configuration.

Irradiation of an acetone solution of cis-6,7,8-trideoxy-1,2:3,4-di-O-isopropylidene-7-C-nitro-α-D-galacto-oct-6-enose (4) with ultraviolet light gives a complex mixture from which the three major products have been isolated: the transisomer of the nitroolefin 4, cis-6,8-dideoxy-1,2:3,4-di-O-isopropylidene-α-D-galacto-oct-5-enos-7-ulose (5), and the transisomer of 5. The structures of the compounds were established by spectroscopic methods. Signal assignments in the nuclear magnetic resonance spectra have been made by spin decoupling.

Addition of nitroethane to 1,2:3,4-di-O-isopropylidene-α-D-galacto-hexodialdo-1,5-pyranose (3) gave a mixture of β-nitro alcohols (4), which was acetylated to afford a mixture of β-nitro acetates (5). Dehydroacetylation of the latter gave cis- and trans-6,7,8-trideoxy-1,2:3,4-di-O-isopropylidene-7-C-nitro-α-D-galacto-oct-6-enose (6and 7) in a ratio of about 6:1, respectively. Addition of ammonia to the cis-nitroolefin (6) gave rapidly a mixture of two stereoisomeric vic-nitroamines (8), which was acetylated to furnish a mixture of two 6-acetamido-6,7-dideoxy-7-C-nitro derivatives (9). The same products (9) were obtained by the action of ammonia in aqueous tetrahydrofuran upon the preponderant β-nitro acetate, followed by acetylation. Vinylation of the aldehyde 3gave a mixture of allylic alcohols (10); the preponderant epimer was obtained pure in crystalline form. The various 8-carbon sugar derivatives are of interest as potential intermediates in the synthesis of the carbohydrate moiety in lincomycin.

The preparation of 6-deoxy-3-C-methyl-2,3,4-tri-O-metliyl-D-allopyranose (7), a branclied-chain sugar with the same constitution as nogalose from the antibiotic nogalamycin, is described. Condensation of the 1-O-acetyl derivative 8with 6-chloropurine by the fusion method gave 6-chloro-9-(6′-deoxy-3′-C-methyl-2′,3′,4′-tri-O-methyl-β-D-allopyranosyl)purine (9), which to our knowledge is the first synthetic, purine nucleoside containing a branched-chain sugar with a pyranose ring.

Martian meteorites are the only direct samples from Mars, thus far. Currently, there are a total of 262 individual samples originating from at least 11 ejection events. Geochemical analyses, through techniques that are also used on terrestrial rocks, provide fundamental insights into the bulk composition, differentiation and evolution, mantle heterogeneity, and role of secondary processes, such as aqueous alteration and shock, on Mars. Martian meteorites display a wide range in mineralogy and chemistry, but are predominantly basaltic in composition. Over the past 6 years, the number of martian meteorites recovered has almost doubled allowing for studies that evaluate these meteorites as suites of igneous rocks. However, the martian meteorites represent a biased sampling of the surface of Mars with unknown ejection locations. The geology of Mars cannot be unraveled solely by analyzing these meteorites. Rocks analyzed by rovers on the surface of Mars are of distinct composition to the meteorites, highlighting the importance of Mars missions, especially sample return. The Mars 2020 Perseverancerover will collect and cache—for eventual return to Earth—over 30 diverse surface samples from Jezero crater. These returned samples will allow for Earth‐based state‐of‐the‐art analyses on diverse martian rocks with known field context. The complementary study of returned samples and meteorites will help to constrain the evolution of the martian interior and surface. Here, we review recent findings and advances in the study of martian meteorites and examine how returned samples would complement and enhance our knowledge of Mars. Scientists learn about the formation and evolution of planets, such as Mars, by studying rock samples. Obtaining rock samples from Mars makes it possible to study them in state‐of‐the‐art laboratories on Earth with high degrees of precision and accuracy. Currently, samples from Mars are obtained as meteorites that have been ejected from the planet. We can study these rocks to learn about volcanic processes and their chemistry and timing in the context of martian geology. This review paper summarizes the information we have learned about Mars's geology by analyzing martian meteorites. Most of the data collected provide evidence that the interior of Mars is compositionally varied with high diversity in chemical makeup throughout time. However, most meteorites are relatively young with few older rocks (older than 2.4 billion years old) analyzed to date. The Mars 2020 mission plans on collecting older samples directly from Mars's surface, in the Jezero crater, for eventual return to Earth, as early as 2031. The study of both meteorites and returned samples is essential to gain a full understanding of the interior composition, evolution, and geological characteristics of different locations on the Red Planet. Martian meteorites are currently the only samples that we possess from the Red PlanetMartian meteorites reveal the compositional diversity of the interior of MarsReturned samples from Mars would allow us to better constrain the compositions of the martian interior and its evolution through time Martian meteorites are currently the only samples that we possess from the Red Planet Martian meteorites reveal the compositional diversity of the interior of Mars Returned samples from Mars would allow us to better constrain the compositions of the martian interior and its evolution through time

In South Africa, a majority of physicians at the Kalafong Hospital antenatal clinic are racially different from their patients, and strict dress regulations have always been enforced in Obstetrics and Gynecology. Junior personnel, however, tend to prefer more casual dress, and it seemed unreasonable to require them to meet a strict dress code if patients did not consider it to be important. For this reason, a research midwife used a structured questionnaire to interview 100 women attending their first antenatal clinic and asked them to respond to photographs of the same physician (male or female) wearing five different outfits. Patients were asked in which outfit they viewed the doctor as being most competent, trustworthy, and friendly. They also were asked how they wished to be addressed by medical staff.

Base‐catalyzed ring closure of homoveratrylurea (II) with diethyl acetamidomalonate (I) yields the acetamidobarbituric acid (III) which is converted into the dihydropyrimidoisoquinolinone hydrochloride (VII) by cyclization, amination with mesidine (V), and deprotection.