Future Ecological Risk Assessment: “Status Humana,” Man as the Measure

The current environmental paradigm of attempting to maintain, to the extent possible, the “status quo” is intellectually dishonest and untenable. Man has long been at least implicitly recognized as “the measure of all things.” Ecological risk assessments (ERAs) need to be based on the reality that humans have primacy in nature and are a major evolutionary force, albeit a selfish one: the “status humana” paradigm. A variety of facts are set out in support of this paradigm and to demonstrate both its relevance and its value. Examples of applications of this paradigm include hormesis, chemicals, food production and biodiversity, socioeconomic and environmental issues, ecotoxicology and bioavailability, introduced species, and environmental relevance.     

Current Status of Alligator sinensis

1IntroductionAlligatorsinensisisakindofvaluablebutrareanimalwhichisdistributedonlyinChi-na.Chinesealligatorsliveinreservoirsandpondsinthehillsidesbetweenthemiddleandup-perreachesoftheYangtzeRiver.Historically,thedistributionareaoftheChinesealligatorsreached34.5millionhectaresandthenumberreachedthelevelofbeing"tooeasytogetanddisgust"duringtheWesternHanDynasty(206B.C.-24A.D.).Withtheinterruptionofhumanactivities,thedistributionareaofA.sinensisisdecreasingcontinuouslyandthenumberisreducinggr…     

Renal Homotransplantation—Current Status

Five years of clinical experience with renal transplantation has led to improved results in terms of surgical technique and the use of immune suppressive drugs.The duration of function of individual grafts is entirely uncertain at present. Some prognosis can be based upon the source of the graft.There is evidence to suggest all grafts will be destroyed by host factors.The employment of tissue-matching techniques offers the most promise for improved results in the immediate future.     

More Status or More Children? Social Status,Fertility Reduction,and Long-Term Fitness

A model is presented that shows that reduced fertility in humans can be explained as part of an evolved strategy to maximize long-term fitness in the face of periodic calamities that result in demographic crashes. Three conditions must be met for this model to be plausible: (1) human population history has been characterized by local periods of growth punctuated by recurrent crashes caused by calamities such as climatically induced resource shortfalls; (2) a strategy is available to individuals that increases the probability of survival through a crash, but that, to implement, requires diverting resources away from producing more offspring; and (3) long-term fitness benefits to increased survivorship through a crisis must outweigh or equal the fitness benefits that would accrue to putting the same resources into higher fertility. We present a model that shows that increases in survivorship can outweigh the benefits of higher fertility even if crises are neither very frequent nor particularly severe.     

Potassium in agriculture – Status and perspectives

In this review we summarize factors determining the plant availability of soil potassium (K), the role of K in crop yield formation and product quality, and the dependence of crop stress resistance on K nutrition. Average soil reserves of K are generally large, but most of it is not plant-available. Therefore, crops need to be supplied with soluble K fertilizers, the demand of which is expected to increase significantly, particularly in developing regions of the world. Recent investigations have shown that organic exudates of some bacteria and plant roots play a key role in releasing otherwise unavailable K from K-bearing minerals. Thus, breeding for genotypes that have improved mechanisms to gain access to this fixed K will contribute toward more sustainable agriculture, particularly in cropping systems that do not have access to fertilizer K. In K-deficient crops, the supply of sink organs with photosynthates is impaired, and sugars accumulate in source leaves. This not only affects yield formation, but also quality parameters, for example in wheat, potato and grape. As K has beneficial effects on human health, its concentration in the harvest product is a quality parameter in itself. Owing to its fundamental roles in turgor generation, primary metabolism, and long-distance transport, K plays a prominent role in crop resistance to drought, salinity, high light, or cold as well as resistance to pests and pathogens. Despite the abundance of vital roles of K in crop production, an improvement of K uptake and use efficiency has not been a major focus of conventional or transgenic breeding in the past. In addition, current soil analysis methods for K are insufficient for some common soils, posing the risk of imbalanced fertilization. A stronger prioritization of these areas of research is needed to counter declines in soil fertility and to improve food security.     

2004 SIVB Congress Symposium Proceedings “Thinking Outside the Cell”: Plant Protoplast Technology: Status and Applications

Summary Plant protoplasts provide an enabling technology to underpin aspects of development, physiology, and genetics. Reliable procedures are available to isolate and culture protoplasts from monocotyledons and dicotyledons. Several parameters influence the topipotency of protoplasts and their derived cells, particularly the source tissue, culture medium, and environmental factors. Novel approaches to maximize the efficiency of protoplast-to-plant systems include techniques already established for animal and microbial cells, such as electrostimulation and exposure of protoplasts to surfactants and artificial respiratory gas carriers, especially perfluorochemicals and hemoglobin. Somatic hybridization by protoplast fusion is undergoing a resurgence of interest, since it enables nuclear and cytoplasmic genomes to be combined at the interspecific and intergeneric levels without prior knowledge of gene location, or involvement of recombinant DNA technology. DNA uptake into protoplasts has applications in transient and stable transformation, including the generation of transplastomic plants of commercial importance in molecular pharming. Other applications of isolated protoplasts are in studies of membrane function, cell structure, and longer-term toxicological assessments. Despite the century that has elased since protoplasts were first isolated, they still make a significant contribution to many aspects of modern plant biotechnology.     

Twenty Five Years of the “Psychosine Hypothesis”: A Personal Perspective of its History and Present Status

Twenty five years ago in 1972, a hypothesis was introduced to explain the pathogenetic mechanism underlying the unusual cellular and biochemical characteristics of globoid cell leukodystrophy (Krabbe disease). It postulated that galactosylsphingosine (psychosine), which cannot be degraded due to the underlying genetic defect, is responsible for the very rapid loss of the oligodendrocytes and the consequent paradoxical analytical finding, the lack of accumulation of the primary substrate, galactosylceramide, in patients' brain. It took nearly ten years before the actual accumulation of psychosine was demonstrated in human Krabbe patients and also in the brain of twitcher mice, an equivalent murine mutant. Meanwhile this psychosine hypothesis has been extended to Gaucher disease and then to a more general hypothesis encompassing all sphingolipidoses that the lyso-derivatives of the primary sphingolipid substrates of the defective enzymes in respective disorders play a key role in their pathogenesis. Some of these extensions not only remain speculative without conclusive factual evidence but may eventually turn out to be an overstretching. This article attempts, from my personal perspective, at tracing historical development of the psychosine hypothesis and examining its current status and possible future directions.     

Respiratory Viruses—Current Status and Future Prospects

The application of tissue culture technology has revealed several new groups of viruses, comprising scores of different serotypes, as important causes of upper and lower respiratory tract disease in man. Other agents as yet unrecognized undoubtedly exist.Present epidemiologic data, although still incomplete, point up the unique importance of certain of these viruses in respiratory diseases.The particular type and severity of respiratory syndrome produced by a virus is determined by the immune status of the host, by the presence of complicating disease and by characteristics intrinsic in the infecting agent itself.Respiratory virus control might be particularly beneficial in certain groups, particularly persons with allergic sensitivity and chronic pulmonary disease.For control of viral respiratory disease, active immunization would provide significant protection but highly polyvalent vaccines might be necessary. Adjuvants could be helpful in this regard.Certain vaccines formerly in use were produced from strains of viruses which have recently been shown to be oncogenic in animals. In addition, hybridization of viruses can occur, resulting in the incorporation of the oncogenic potential of one agent into the genetic constitution of another. The significance of these biologic phenomena to vaccination programs has yet to be defined.Passive immunization would provide short-lived protection and would find application only in uniquely susceptible populations or at times of augmented risk. Active immunization of pregnant women, however, could provide increased breadth and duration to the transplacental passive immunity in the newborn.Interferon-inducing agents could potentially provide broad spectrum antiviral protection, but the extent and duration of their effectiveness are unknowns.Certain chemical agents have been shown to have prophylactic and therapeutic effects against a limited number of clinically severe viral diseases. Finally, limited data suggest that climatic control in places of public gathering might be worth evaluating as a means of controlling the spread of viral respiratory infections.     

FEMALE INFERTILITY—The Present Status of Treatment

Few barren women have gynecological abnormalities sufficient to prevent conception. Hormonal stimulation appears to be effective in some cases; and sometimes pregnancy follows instrumental treatment, possibly as a result of dislodgement or displacement of polyps in the process. There is nebulous evidence that psychogenic factors may play a part in infertility.If the fallopian tubes are occluded, operation to restore patency is not likely to clear the way to conception.     

BACTERIAL AND CHEMICAL WARFARE—The Current Status

For fourteen years public attention has been focused so sharply on atomic weapons as to lose sight of other, less spectacular but equally significant advances in the art of warfare.In the shadows cast by brilliant research in nuclear physics are hidden startling advances in the field of chemical and biological weapons. These weapons, as now developed, are not only capable of producing mass casualties quite comparable with those of atomic bombs, but they also possess certain advantages which may make them the weapons of choice for an unscrupulous enemy.If war should come, it is the medical profession which will have the sole responsibility for protecting the citizens of California against these weapons, and we can therefore delay no longer in acquainting ourselves with their potentialities and characteristics.In this task, we are working under two serious handicaps. The first is that our classical medical training affords little appreciation of the real danger, and the second is the cloak of secrecy surrounding the entire subject.     

Coronary Care Units—The Status in California

In order to determine the status of Coronary Care Unit activity in California hospitals, especially as it pertains to nurse training, a survery was conducted by the California State Department of Public Health. More than 95 percent of hospitals that were questioned responded. Only one-third of the hospitals reported they neither had a unit nor plans to build one. All units in operation were either directed by an individual medical director or by a Coronary Care Unit Committee.The survey indicated that in some hospitals with operational units, nurses were not permitted to perform life-saving resuscitative procedures. All operational units reported in-service education programs of some type. Many hospitals indicated they would like to have Coronary Care Unit training programs to which they could send nurses. The reasons why nurses may not perform important resuscitative procedures are discussed as well as the need for Coronary Care Unit training programs for both physicians and nurses in California.