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/ This paper reports on the development of abiogeographic-based protected area selection procedure (PASP) that addresseslimitations of current reserve selection methods such as inflexibility,restrictive criteria structures, and disregard of social criteria. We arguethat selection criteria are legitimately identified through the politicalprocess and can therefore have both social and biological content. PASPprovides a systematic, flexible and efficient procedure for identifying anetwork of protected areas that satisfies a given set of selection criteria.PASP has 11 steps divided into three main stages: compilation, selection, andvalidation. A selection algorithm is used into which criteria specific to thebiogeographic region under study can be incorporated. The procedure is ableto accommodate both nominal and ranking criteria and gives the analyst theopportunity to specify thresholds and targets for each criterion. Otherfeatures of PASP include the minimization of data collection effort,consideration of reserve design principles, and inclusion of a networkevaluation as a check to ensure that politically determined objectives havebeen met.KEY WORDS: Land use; Protected area networks; Selection algorithms

Howsepian has presented a number of thought experiments, which are designed to undermine my claim that our identity through time is grounded in the continued existence of those structures in our brains which directly underlie mental functioning. I argue that the conclusions which Howsepian draws from these thought experiments are mistaken, and that his discussion of them is vitiated, in particular, by his failure to distinguish between personal identity and the identity of the associated human organism.

Objective: Polyarteritis nodosa (PAN) has been used as a generic term for systemic vasculitis. The distinction between classic PAN and microscopic polyangiitis (MPA) has not always been made. The aims of this study were to compare the American College of Rheumatology (ACR) criteria for PAN with the Chapel Hill Consensus Conference (CHCC) definitions of classic PAN and MPA, and to estimate the annual incidence of PAN and MPA., Methods: The 1990 ACR criteria and CHCC definitions for systemic vasculitis were applied to an unselected cohort of 130 patients with systemic vasculitis attending a single district hospital in the UK between February 1, 1988 and January 31, 1994., Results: Eight patients who met the ACR criteria for PAN and who also met the CHCC definition of MPA but not classic PAN were identified. A further 5 patients met the CHCC definition of MPA but not the ACR criteria for any other type of systemic vasculitis. No patient who met the CHCC definition of classic PAN was identified. The annual incidence of MPA was calculated to be 3.6/million (95% confidence interval 1.7-6.9), and the annual incidence of PAN (ACR criteria) was 2.4/million (95% confidence interval 0.9-5.3)., Conclusion: Classic PAN as defined by the CHCC is rare, because small vessel involvement is excluded from this definition.

Rupture and leakage are recognized problems associated with silicone breast implants. Data are scarce about the durability of the silicone shell, and the life span of this device is unknown. The purpose of this study was to investigate the strength of silicone breast implants. Thirty implant shells were subjected to mechanical testing. Twenty-nine of the shells were tested after explanation, and one unused implant served as a control to validate the testing method. Implantation time varied from 4 months to 20 years, and all shells were tested, regardless of condition. Fourteen implant shells were intact, eight were leaking, and seven were ruptured. All ruptured implants had been in place for 10 years or longer. The breaking force of all excised shell specimens ranged from 2.6 to 22.4 N (0.6 to 5.0 lb.). Specimens from the control "high performance" shell required 15.5 to 25.6 N (3.5 to 5.8 lb) of force to fail. The weakest group was from thin-shelled implants between 10 and 16 years of age. More than half these specimens failed with less than 1 lb of force. The average breaking force of ruptured shell material was less than that of intact shells. A comparison of strength data in this study with manufacturers' data suggests that breaking force is dependent on implant type, shell thickness, and implantation time.

Recently it has been demonstrated that human antibody fragments with binding activities against self antigens can be isolated from repertoires of rearranged V genes from non-immunized humans. We have applied phage display technology to study the B cell repertoire for antibody activity against neutrophil cytoplasmic antigens. These antibodies may play an important role in Wegener's granulomatosis (WG) and related forms of vasculitides. Autoantibodies in patients with WG are directed against proteinase 3. The immunodominant antigen in other forms of vasculitis is myeloperoxidase, but the B cell response can also be directed against other neutrophil enzymes, e.g. lysozyme, human neutrophil elastase, lactoferrin and cathepsin G. We show here that anti-self reactivity against neutrophil cytoplasmic antigens can be detected in the rearranged V gene repertoire of healthy individuals and that the reactivity can be directed against structural related epitopes which are present on different neutrophil cytoplasmic antigens. The scFv with binding activities were sequenced and the V gene usage, the level of somatic mutations and the immunoserological characteristics of the antibody fragments are discussed. Further evidence is presented that antibody fragments consisting only of a heavy chain variable domain can recognize neutrophil cytoplasmic antigens in a specific manner. These single-domain antibody fragments were used in experiments designed to establish the relative role of the light chain variable domains in antigen binding.

Rates of bovine photoreceptor gene transcription, as measured by nuclear run-on assays, exhibit gene-specific patterns of regulation. Here we investigate initiation and elongation in nuclear run-on assays with the use of sarkosyl to further understand the nature of these gene-specific elements. Opsin transcription, alone among several genes tested, proved sarkosyl-sensitive. This sensitivity is maximal in adult retinas, with inhibition first detected in mid-third trimester fetal retinas. Therefore, opsin transcription appears to involve different regulatory elements in adult and fetal retinas, implying a fetal to adult switch in the control of opsin gene expression. Although this regulatory switch is initially activated at a time when the fetal outer nuclear layer of the retina first achieves adult-like morphology, further maturation of opsin regulation takes place postpartum since levels of sarkosyl sensitivity are almost 5-fold greater in adult retinas compared to the 7.5 month fetus. We also show that the sarkosyl-induced reduction of opsin transcription is not due to prevention of de novo RNA polymerase II initiation in the run-on reaction, suggesting the detergent alters a positive-acting, postinitiation component of the transcriptional apparatus. Since levels of opsin transcription with sarkosyl are similar to those of the other visual transduction genes with or without sarkosyl, this detergent-sensitive transcriptional component appears to account for the singularly high, gene-specific rate of opsin transcription in retinal photoreceptor cells.

"This paper gives an overview of the recent demographic history of countries in sub-Saharan Africa, especially the start of a fertility decline. After discussing the evidence for a decline, and the nature of changes in fertility behaviour, the paper moves on to look at possible causes, in relation to development policy. Mortality, cultural structure, the status of women, education and economic crisis are all considered as candidates. The conclusion is reached that available evidence raises as many questions about the causes of fertility decline as it resolves, particularly in our understanding of the process of change. Finally, the potential consequences of falls in fertility and population growth slowdown in sub-Saharan Africa are considered.", (excerpt)

The present studies were carried out to analyze the neurochemical and behavioral effects of peripheral sigma ligand administration in the rat. Based upon previous studies which showed an increase in turning behavior following unilateral intranigral administration of sigma ligands, we determined the effects of two sigma ligands, 1,3-di-o-tolylguanidine (DTG) and (+)-pentazocine, on extracellular dopamine levels in the rat striatum. Dopamine levels were monitored via microdialysis in awake freely moving animals following i.p. injection of the ligands. Both DTG (1 and 3 mg/kg) and (+)-pentazocine (10 mg/kg) produced a significant (30-50%) increase in extracellular dopamine. Given the relatively high concentration of sigma receptors in brain nuclei involved in facial and mouth movements, we have also determined the effects of the two sigma ligands on facial movements. Both ligands produced a significant increase in vacuous chewing movements, suggesting that studies on the consequences of sigma receptor activation may have relevance to animal models of human dystonia and/or dyskinesia.

The impact of small differences in selenium exposure during the first year of life was investigated in male Wistar rats. Forty-five rats were evaluated in two experiments. Rats were provided diets that contained sucrose as the sole carbohydrate to induce an elevation in blood triglycerides, cholesterol, glucose, and insulin. In each experiment one-half the rats received 0.1 mg Se/kg and the other half 0.2 mg Se/kg diet. Both levels of selenium supported normal activity of the marker for selenium sufficiency erythrocyte glutathione peroxidase. In experiment 1 rats were maintained in galvanized cages and in experiment 2 they were housed in stainless steel cages. In both experiments rats provided 0.2 mg Se/kg diet had fewer acellular degenerating capillaries and a higher ratio of pericyte to endothelial cells in the capillary wall than those fed 0.1 mg/kg as well as fewer vessels over the optic disc head. In the second experiment, the height of the central choroid was also greater in rats exposed to the higher level of selenium suggesting that the element protected the capillaries in this region from degeneration. In contrast to vascular tissue, the retinal parenchymal tissue was unaffected by the level of selenium exposure. These results are consistent with the hypothesis that the microvasculature has a unique requirement for selenium.

This paper evaluates the effect of small differences in selenium exposure, within the safe range, on the glomerular vascular tufts of rats fed high-sucrose diets. In the first experiment male Wistar rats were housed in galvanized cages and were provided sucrose-based diets to induce a mild chronic insult to the microcirculation. One group of rats received the diet prepared to contain 0.10 mg Se/kg and another group 0.21 mg Se/kg. To assure that the galvanized metal cages were not influencing the results of the experiment this protocol was repeated in a second experiment wherein rats were housed in stainless steel cages. The levels of Se used supported normal activity of the long-term indicator of Se sufficiency, erythrocyte glutathione peroxidase. In both experiments rats fed diets containing 0.21 mg Se/kg had larger Bowman's capsules (P < 0.01) and vascular tufts (P < 0.01). Vascular tufts from these rats also contained a higher proportion of open capillary lumen (P < 0.01), contained less cytoplasmic and extracellular material (P < 0.001), and had larger nuclei (P < 0.001) than those fed 0.10 mg Se/kg. A third study was designed to determine if the selenium-dependent differences in nuclear size were indicative of this being a site of incorporation. Year-old rats subjected to the same protocol as those in the second experiment were given 75Se, by injection into the femoral vein, to label the sites of incorporation. Glomeruli were purified and subjected to subcellular fractionation. Ninety percent of the radioactivity was associated with the crude nuclear fraction. Purification of the crude nuclear fraction demonstrated that the radioactivity was associated with the nuclei.

Alcohol consumption can adversely affect an individual's response to infection. We have shown that alcohol has a direct suppressive effect on numbers of antibody-secreting cells in antigen-activated B lymphocytes but does not suppress the early membrane and intracellular events that are associated with binding of antigens to specific receptors. The studies reported here were designed to determine whether alcohol inhibits immunoglobulin synthesis. When 150 mg/dl ethanol was added to anti-mu-stimulated purified B cells, proliferation was inhibited. Similar exposure to ethanol inhibited production of messenger RNA for kappa chain in anti-mu-stimulated B cells but did not affect total RNA production or messenger RNA for beta-actin. Thus alcohol inhibits both the proliferation of antigen-activated B lymphocytes and their synthesis of immunoglobulin.

Injury to microvessels caused by the chronic consumption of sucrose can be prevented by selenium (Se). The objective of this study was to determine the temporal sequence of changes in serum triglycerides, total cholesterol, glucose, and insulin induced by sucrose and their relationship to Se status and microvascular injury. Two groups of 24 Wistar rats were fed ad libitum diets in which the entire carbohydrate was either corn starch or sucrose. Two other groups were fed identical diets supplemented with 0.1 micrograms Se/g. At 6, 8, and 10 mo, eight rats from each group were fasted for 12 h and had blood taken. Rats were then given a glucose tolerance test and killed, and their retinal microvessels were evaluated for injury. After 6 mo, sucrose-fed rats had elevated triglycerides and total cholesterol. Abnormal glucose clearance and hyperinsulemia developed after 8 mo. Evidence of microvascular injury became apparent after 10 mo. These changes did not occur in rats provided the starch-based diets, and microvascular injury did not develop in the sucrose-fed rats provided supplemental Se. Glutathione peroxidase activity was normal in all groups throughout the 10-mo experiment. These results chronicle the sucrose-induced systemic insult and show that the protective effect of Se does not occur by diminishing this insult to the microvessels.

Drinking water samples concentrated by freeze drying were found to be mutagenic in a mammalian tissue culture assay using Chinese hamster embryonic lung cells (V79). The mutagenicity could be enhanced by the promoter 12-O-tetradecanoyl-phorbol-13-acetate. The water itself was also shown to contain promoting chemicals. The mutation frequency of cells pretreated with low levels of benzo(a)pyrene was increased following subsequent exposure to the concentrated water sample. Approaches to estimate the risk involved in exposure to present drinking water are proposed.

Increased use of contaminated water and long-range plans for the direct use of recycled water necessitate a careful assessment of the potential health effect on the population. Selected in vitro assays were used to evaluate the mutagenic and carcinogenic potential of a concentrated, recycled water sample. It was found that the concentrated water induced mutagenicity in hamster lung cells and cellular transformation in human embryonic lung fibroblasts. The use of in vitro analyses in conjunction with epidemiologic studies in determining the human risks of environmental carcinogens is discussed.

We have isolated a new type of temperature-sensitive mutant of simian virus 40 (SV40) that is capable of productive infection in permissive cells but not of maintenance of viral DNA integration in transformed cells at the conditional temperature. Virus development is induced when cells transformed by this mutant are shifted to temperatures above 39 degrees C, but is not induced below this temperature. The plaque-purified, temperature-sensitive mutant virus confers heat inducibility to new host cells, indicating that the conditional function is a property of the viral genome. Unlike previously described temperature-sensitive SV40 mutants, in (ts)-1501 is capable of productive infection in permissive cells at the conditional temperature. The morphology, growth, and oncogenicity of in (ts)-1501-transformed cells at 37 degrees C are similar to those of cell lines transformed by wild-type SV40. HK10-c2(in(ts)-1501), a cloned cell line, transformed at 37 degrees C by the mutant virus, exhibits a transient increase in DNA synthesis before cell death at the conditional temperature. Many properties of in(ts)-1501 are analogous to those of the heat-inducible mutants of bacteriophages in which a heat-inactivated protein is responsible for the stable integration of the prophage in the bacterial chromosome.

Observations are reported on six patients with inflammatory polyneuropathy who were treated by plasma exchange. In four cases the polyneuropathy was acute and in two it was chronic or relapsing. Two acute cases and one chronic relapsing case had plasma exchange during a rapidly progressive phase of the disease, and showed a prompt and substantial recovery of function. The other three patients were exchanged when disease activity had reached a plateau. Only minor degrees of improvement were seen in two of these cases. One patient showed an initial mild deterioration before subsequent recovery. There were no significant side effects. These findings are discussed in relation to the pathogenesis and clinical management of inflammatory polyneuropathy.

Chronic inflammation and degenerative tendonitis of the supraspinatus muscle is an important cause of intrinsic shoulder pain. Injury to this muscle is usually caused, not by a single event, but by slight to moderate trauma repeatedly to the same anatomic area. The term repetition strain injury is used to describe this form of microtrauma. Repetition strain injury of the supraspinatus muscle is not an isolated event, but rather a form of microtrauma that affects the entire shoulder girdle. This functional unit must be evaluated and considered in the treatment plan. The authors discuss the diagnosis of this pain syndrome, which is based on the patient's work history, motion and strength testing, and palpation for trigger points. They also provide instruction in treatment involving manipulation with functional and counterstrain techniques combined with home exercise and modification of work posture.

Preparations of human glomerular basement membrane (GBM) were digested with collagenase, and a Goodpasture (GP) antigen rich pool from gel filtration column runs was identified by antibody inhibition radioimmunoassay. The components of the GP antigen pool were separated on polyacrylamide gels, and transferred to nitrocellulose sheets by the 'western' blotting technique. The blots were separately reacted with thirteen GP sera as primary antibody, followed by peroxidase labelled goat anti-human IgG and revealed 45-50K (two bands) and 25-28K (one-three bands) components. No corresponding reactivity was observed using convalescent GP sera or other control sera (normal human serum, rapidly progressive glomerulonephritis with or without pulmonary haemorrhage, and lupus erythematosus) as primary antibody.

The clinical and immunological features of fifteen cases of cryptogenic pulmonary eosinophilia are reported. There were ten women (mean age 35.4 years) and five men (mean age 42 years). Eight gave a previous history of asthma and seven had none. Thirteen of the fifteen patients had negative skin test to common allergens. Many features of a systemic illness were present in the asthmatic and non-asthmatic groups including anaemia, weight loss, fever and a grossly raised ESR. An absolute polymorphonuclear leucocytosis was frequent as well as the obligatory increase in blood eosinophils used as one of our criteria for inclusion. Hepatomegaly (three cases), splenomegaly (four cases) and hilar node enlargement (one case) were seen in the group without asthma. Evidence of renal involvement or necrotizing vasculitis was notably absent and the response to small doses of corticosteroids was dramatic. Immunologically the striking feature was a disproportionate increase in blood eosinophils compared with only minor elevations in the total serum IgE levels. This stands in contrast to patients with bronchopulmonary aspergillosis and helminth infestation. Studies of cytophilic antibodies using histamine liberation after challenge with antibodies to immunoglobulin sub-classes in six patients showed a marked increase in IgG2 and lesser increases of IgE and IgG3. No evidence of antibodies specific to A. fumigatus was found. The amount of cytophilic antibody was also in contrast to that found in bronchopulmonary aspergillosis.

The concentration of airborne microbes, their endotoxins and the prevalence of byssinotic symptoms among workers were measured in the cardrooms of seven cotton spinning, a wool spinning and two cotton waste mills and in a dusty workroom of a group of five willowing mills, a tea-packing plant and a pipe tobacco factory. The concentration of microbes cultured on endoagar plates were found to correlate with byssinosis prevalence (r greater than 0.95, P less than 0.001). The concentration of nutrient agar microbes correlated with prevalence less well (r greater than 0.77, P less than 0.01) and that of fungi and endotoxins not at all.

The effects on cardiac function of feeding a diet high in sucrose to male Wistar rats over an extended period of time (15 months) was examined. This diet produced a diabetic condition which resembled noninsulin dependent diabetes mellitus. Resting hyperglycemia, high circulating insulin and triglyceride levels were observed in these animals. Further, the sucrose fed animals were overweight in comparison to chow fed control animals. Contractile protein Ca2+-ATPase activity was measured as a biochemical estimate of cardiac contractile function. Myosin and actomyosin Ca2+-ATPase activities of isolated myofibrillar fractions from hearts of experimental animals were depressed in comparison to chow fed control rats. Myosin K+-EDTA activity was also altered. The results demonstrate for the first time a defect in contractile protein Ca2+-ATPase activity in rat hearts using a model of noninsulin dependent diabetes mellitus. As the animals were euthyroid, thyroid hormone alterations in these animals were unlikely to influence the results. The results also demonstrate that insulin could not be a direct factor associated with cardiac pathology in diabetes. Instead, cardiac dysfunction may be associated with other, as yet undefined, metabolic abnormalities which accompany the diabetic state.

The purpose of this research was to investigate the phenomenon of misbehavior described by Breland and Breland (1961). Rats were trained to obtain ball-bearings and drop them in a hole for food or water reinforcers. In confirmation of the Brelands' observation, many subjects were slow to deliver the balls, and frequently attempted to chew them before they were dropped. A series of four experiments, in which the same rats were used throughout, showed that delivery times tended to be longer with food than with water, and that these times increased when nylon balls were substituted. The effect of motivational level was investigated by varying both deprivation and amount of prefeeding; no effect on delivery time was detected, although other measures of performance were affected by motivational factors. Similar results were obtained in a final experiment that employed a new set of naive subjects. The studies demonstrated that misbehavior can be studied in an experimental situation, and the results supported an analysis in terms of competition between stimulus-reinforcer and response-reinforcer contingencies. The question of why such effects have not been reported in previous token reinforcer studies was unanswered.

The purpose of the present study was to examine the effects on cataractogenesis of daily sc administration of the Ca2+ antagonist drug verapamil to diabetic rats. Streptozotocin-induced diabetic rats were given verapamil half-way through the 8-week experimental period or during the full 8 weeks of diabetes. Verapamil administration had no effect on the high blood glucose values, low circulating insulin levels, or elevated triglyceride and cholesterol concentrations in the diabetic rats. Untreated diabetic rats had a 90% incidence of cataracts. Four weeks of verapamil administration reduced this incidence to 41%, and a full 8 weeks of drug treatment further lowered the incidence to 20%. Diltiazem, another Ca2+ antagonist, lowered the incidence of cataracts in the diabetic rats to a similar extent. Verapamil administration to the diabetic animals also partially protected against the presence of retinal microangiopathy in the diabetic animals. Lenticular hydration and lipid accumulation were only indirectly related to cataractogenesis in the diabetic rats and its protection by verapamil treatment. Lenticular electrolyte imbalance, particularly Ca2+, in the diabetic animals was closely correlated with cataract formation, and verapamil significantly reduced the alterations in these ion concentrations. The present results demonstrate the efficacy of verapamil as a protective agent against cataractogenesis and some retinal damage in diabetic animals. Most importantly, this occurs in the absence of any change in the glycemic status of the diabetic animals. The findings strongly support a role for lenticular Ca2+ imbalance in cataract development in diabetes and provide initial evidence to suggest its clinical use in the diabetic population at risk for blindness.