Wheat germ hemicellulose is an absolute requirement for growth and development of the southwestern corn borer

The southwestern corn borer, Diatraea grandiosella Dyar, is a major pest of corn, Zea mays L., in the southern United States. To search for plant allelochemicals, chemically defined insect diets are commonly used, but southwestern corn borer larvae did not grow and develop unless a subnutritional amount of wheat germ was incorporated in the amino acid diet. Fractionation led to identification of hemicellulose as the active component which was then characterized. The hemicellulose permitted insect growth on a protein-free amino acid diet. Microfloral involvement was ruled out because larvae grew and developed free of intestinal microbes. Therefore, this insect has an absolute requirement for hemicellulose that has evidently not been demonstrated with other invertebrates or vertebrates. This finding is of general interest because hitherto, the contributions of hemicellulose to nutrition have generally been considered to be associated chiefly with microfloral conversion to assimilable carbohydrates. Investigations should be conducted to determine whether hemicelluloses are also important or essential for growth of vertebrates including mammals by mechanisms that may not have been considered.     

The moral case against euthanasia. Catholics must articulate persuasive arguments to counter the cultural rush toward assisted suicide

Catholics who adhere to a consistent ethic of life are going to face tougher opposition as they struggle to defend society's most vulnerable members. The major ethical contention will concern the ethics of dying. Unfortunately, there have not been well-articulated moral arguments to counter society's rush toward physician-assisted suicide and euthanasia. Catholics must articulate a persuasive ethical ideal for dying a truly good death. It is crucial to achieve a balance: between valuing individual autonomy and protecting the common good; between affirming the goodness of life and accepting death as a reality of the life cycle. Another challenging piece of the moral argument lies in convincing people that the means and processes used to achieve a goal are rarely neutral. Another serious problem with permitting the killing of self or others is that one cannot ever be certain of the agent's motivation. And when an individual's subjective determination of a need to choose death is given ultimate validity, there is no way to call a halt. If medical mercy killing becomes acceptable, social pressure can mount for an ill person to ask for death to relieve the family burdens. Maintaining an absolute prohibition against actively taking a human life--self or other, with or without consent, dying or not--is necessary to protect human communal bonds.     

Managing (In)differently: The management and delivery of Australian nursing care under the economic rationalists

Conclusion Economic (mis)management in Australia has understandably been influenced by the experiences of countries such as the UK and the USA with which Australia has traditionally had a close relationship. However, the uncritical acceptance of economic rationalism is an indication of our nation's seduction by the possibility of a quick fix for a struggling economy. In accepting economic rationalism there has been a dismissal, or at least a failure to take account of, both past Australian experiences and the overseas experience—including the recent experience of a close neighbour, New Zealand, whose health system is under severe strain.The introduction of economic rationalist programmes into the Australian health sector was an attempt to contain expenditure and at the same time reduce dependence on the public system. This has failed to happen on both counts. Its only real achievement has been to produce yet more evidence of the practical inadequacies of economic rationalism in general.     

Penicillium peritonitis in an adolescent receiving chronic peritoneal dialysis

A 19-year-old female on chronic peritoneal dialysis developed acute peritonitis; multiple peritoneal fluid and catheter tip cultures yielded Penicillium species. She promptly responded to catheter removal and intravenous amphotericin B, followed by oral fluconazole, without further recurrences 1 year later. This is the first reported case of Penicillium peritonitis in the pediatric population. We review the microbiology and clinical spectrum of this disease, as well as the few previous reported cases in adults. Received: 2 November 1998 / Revised: 1 February 1999 / Accepted: 4 February 1999     

Serum cholesterol and impulsivity in personality disorders

Decreased serum cholesterol has been associated with impulsive aggressive behaviors. This study was designed to explore the relationship between serum cholesterol levels and measures of impulsive aggression in personality disordered patients. Forty-two personality disordered patients (14 borderline personality disorder, 28 other personality disorders) were included. Fasting serum cholesterol was measured by standard enzymatic assay. An ANOVA was performed with factors of gender and diagnosis, looking at two-way interactions between the factors and serum cholesterol. Patients with borderline personality disorder were found to have significantly lower serum cholesterol than non-borderline personality disorders. A significant interaction effect was also seen between gender and diagnosis with the male patients having lower cholesterol levels. This study suggests there may be a relationship between borderline personality disorder and low serum cholesterol.     

Conformational preferences in a benzodiazepine series of potent nonpeptide fibrinogen receptor antagonists

Previously, we reported the direct design of highly potent nonpeptide 3-oxo-1,4-benzodiazepine fibrinogen receptor antagonists from a constrained, RGD-containing cyclic semipeptide. The critical features incorporated into the design of these nonpeptides were the exocyclic amide at the 8-position which overlaid the Arg carbonyl, the phenyl ring which maintained an extended Gly conformation, and the diazepine ring which mimicked the gamma-turn at Asp. In this paper, we investigate conformational preferences of the 8-substituted benzodiazepine analogues by examining structural modifications to both the exocyclic amide and the seven-membered diazepine ring and by studying the conformation of the benzodiazepine ring using molecular modeling, X-ray crystallography, and NMR. We found that the directionality of the amide at the 8-position had little effect on activity and the (E)-olefin analogue retained significant potency, indicating that the trans orientation of the amide, and not the carbonyl or NH groups, made the largest contribution to the observed activity. For the diazepine ring, with the exception of the closely analogous 3-oxo-2-benzazepine ring system described previously, all of the modifications led to a significant reduction in activity compared to the potent 3-oxo-1, 4-benzodiazepine parent ring system, implicating this particular type of ring system as a desirable structural feature for high potency. Energy minimizations of a number of the modified analogues revealed that none could adopt the same low-energy conformation as the one shared by the active (S)-isomer of the 3-oxo-1, 4-benzodiazepines and 3-oxo-2-benzazepines. The overall data suggest that the features contributing to the observed high potency in this series are the orientation of the 3-4 amide and the conformational constraint imposed by the seven-membered ring, both of which position the key acidic and basic groups in the proper spatial relationship.