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A psychoanalytic study of migration: its normal and pathological aspects.

Without maintaining that it always follows the same steps, we could say that the migratory process passes through several phases. The feelings that prevail are those of intense sorrow for all that has been abandoned or lost, fear of the unknown, and the very profound experiences of loneliness, privation, and helplessness. Paranoid, confusional, and depressive anxieties occupy the scene in turn. This stage may be followed or replaced by a manic state in which the immigrant minimizes the transcendental significance of the change in his life or, on the contrary, magnifies the advantages of the change and overvalues everything in the new situation, disdaining what has been lost. After a variable period of time, nostalgia appears, and sorrow for the lost world. The immigrant begins to recognize feelings previously dissociated or denied and becomes capable of "suffering" his pain ("growing pains") while, at the same time, he becomes more accessible to the slow and progressive incorporation of elements of the new culture. The interaction between his internal and external world becomes more fluid. Recovery of the pleasure of thinking and desiring and of the capacity for making plans for the future, in which the past is regarded as such and not as a "lost paradise" where one constantly longs to return. In this period, it could be considered that mourning for the country of origin has been worked through to the maximum extent possible, facilitating integration of the previous culture into the new culture, without the need to renounce the old. All of this promotes an enrichment of the ego and the consolidation of a more evolved sense of identity.

Acculturation↗

Neuropathic pain from an experimental neuritis of the rat sciatic nerve.

Painful peripheral neuropathies involve both axonal damage and an inflammation of the nerve. The role of the latter by itself was investigated by producing an experimental neuritis in the rat. The sciatic nerves were exposed at mid-thigh level and wrapped loosely in hemostatic oxidized cellulose (Oxycel) that on one side was saturated with an inflammatory stimulus, carrageenan (CARRA) or complete Freund's adjuvant (CFA), and on the other side saturated with saline. In other rats, a myositis was created by implanting Oxycel saturated with CFA into a pocket made in the biceps femoris at a position adjacent to where the nerve was treated. Pain-evoked responses from the plantar hind paws were tested before treatment and daily thereafter. Statistically significant heat- and mechano-hyperalgesia, and mechano- and cold-allodynia were present on the side of the inflamed nerve (CARRA or CFA) for 1-5 days after which responses returned to normal. There were no abnormal pain responses on the side of the saline-treated nerve, and none in the rats with the experimental myositis. The abnormal pain responses were inhibited by N-methyl-D-aspartate receptor blockade with MK-801, but were relatively resistant to the dose of morphine tested (10 mg/kg). Light microscopic examination of CARRA-treated nerves, harvested at the time of peak symptom severity, revealed that the treated region was mildly edematous and that there was an obvious endoneurial infiltration of immune cells (granulocytes and lymphocytes). There was either a complete absence of degeneration, or the degeneration of no more than a few tens of axons. Immunocytochemical staining for CD4 and CD8 T-lymphocyte markers revealed that both cell types were present in the epineurial and endoneurial compartments. The endoneurial T-cells appeared to derive from the endoneurial vasculature, rather than from migration across the nerve sheath. We conclude that a focal inflammation of the sciatic nerve produces neuropathic pain sensations in a distant region (the ipsilateral hind paw) and that this is not due to axonal damage. The neuropathic pain is specific to inflammation of the nerve because it was absent in animals with the experimental myositis and in those receiving sham-treatment. These results suggest that an acute episode of neuritis-evoked neuropathic pain may contribute to the genesis of chronically painful peripheral neuropathies, and that a chronic (or chronically recurrent) focal neuritis might produce neuropathic pain in the absence of significant (or clinically detectable) structural damage to the nerve. The model that we describe is likely to be useful in the study of the neuroimmune factors that contribute to painful peripheral neuropathies.

Analysis of Variance↗

Morbidity mortality paradox of 1st generation Greek Australians.

There is evidence in Australia that 1st generation Greek Australians (GA), despite their high prevalence of cardiovascular disease (CVD) risk factors (e.g. obesity, diabetes, hyperlipidaemia, smoking, hypertension, sedentary lifestyles) continue to display more than 35% lower mortality from CVD and overall mortality compared with the Australian-born after at least 30 years in Australia. This has been called a 'morbidity mortality paradox' or 'Greek-migrant paradox'. Retrospective data from elderly Greek migrants participating in the International Union of Nutrition Sciences Food Habits in Later Life (FHILL) study suggests that diets changed on migration due to the: (i) lack of familiar foods in the new environment; (ii) abundant and cheap animal foods (iii) memories of hunger before migration; and (iv) status ascribed to energy dense foods (animal foods, white bread and sweets) and 'plumpness' as a sign of affluence and plant foods (legumes, vegetable dishes, grainy bread) and 'thinness' as a sign of poverty. This apparently resulted in traditional foods (e.g. olive oil) being replaced with 'new' foods (e.g. butter), 'traditional' plant dishes being made more energy dense, larger serves of animal foods, sweets and fats being consumed, and increased frequency of celebratory feasts. This shift in food pattern contributed to significant weight gain in GA. Despite these potentially adverse changes, data from Greece in the 1960s (seven countries study) and from Australia in the 1990s (FHILL study) has shown that Greek migrants have continued to eat large serves of putatively protective foods (leafy vegetables, onions, garlic, tomatoes, capsicum, lemon juice, herbs, legumes, fish) prepared according to Greek cuisine (e.g. vegetables stewed in oil). Furthermore, GA were found to return to the traditional Greek food pattern with advancing years. We suspect that these factors may explain why GA have recently been found to have over double the circulating concentrations of antioxidant carotenoids, especially lutein, compared with Australians of Anglo-Celtic ancestry. This in turn may have helped to make the CVD risk factors 'benign' and reduce the risk of death. This raises the question whether specific dietary guidelines need to be developed for recent migrants to Australia, encouraging them to retain the best of their traditional cultures and include the best of the mainstream culture.

Acculturation↗

Behavioural thermoregulation of chum salmon during homing migration in coastal waters.

Homing Pacific salmon are suggested to utilise directional cues in shallow water while migrating in coastal waters. Since salmonids are typical cold-water fish, they may have to cope with warm surface water while gathering directional information. We studied behavioural thermoregulation of 31 free-ranging chum salmon Oncorhynchus keta using micro data loggers off the Sanriku coast from early October to December. The surface water temperature was approximately 20 degrees C in early October and decreased to approximately 12 degrees C in December. The seasonal change of water temperature transformed the behaviour of salmon markedly from deep diving to shallow swimming. In October, salmon frequently dived to depths exceeding 100 m. Duration of deep dives tended to be prolonged as the thermal difference between sea surface and bottom water increased. The results indicated that salmon sought the coolest thermal refuge that they could exploit by vertical movement. Thermal refuge could be a way for salmon to minimise metabolic energy cost; however, salmon repeatedly returned to the surface water column. We found a positive correlation between surface swimming of salmon and the presence of cool covering water, which could contain river waters. This suggests that salmon tend to be risk-prone when subjected to a high concentration of directional cues. Salmon in December spent most of their time in shallow water. These findings suggest that salmon adjusted their behavioural strategy with the hydrographic structure of the sea in order to achieve a balance between acquiring directional cues and behavioural thermoregulation.

Animals↗

Total hip arthroplasty in juvenile rheumatoid arthritis. Two to eleven-year results.

From 1971 to 1980, forty-five patients with juvenile rheumatoid arthritis had eighty-three cemented total hip replacements at The Hospital for Special Surgery and North Carolina Memorial Hospital. Thirty-four of these patients, with sixty-two involved hips, returned for examination and radiographs. The average age of these thirty-four patients at the time of surgery was twenty-six years, and twenty-seven of them, with forty-nine involved hips, were thirty years old or less. The average length of follow-up was six years (range, two to eleven years), with forty-one hips having been followed for five to eleven years. According to The Hospital for Special Surgery hip-rating system, thirty hips were rated excellent; nineteen, good; nine, fair; and four, poor. Of the four hips with a poor result, two (in the same patient) had severe heterotopic ossification with ankylosis postoperatively, and two had required revision: one for acetabular loosening six years after replacement and the other for a broken stem of the femoral component ten years postoperatively. Radiographic review of the sixty-two hips demonstrated progressive radiolucencies or migration of 26 per cent of the acetabular components and 8 per cent of the femoral components. The frequency of acetabular migration or progressive radiolucencies was related to the postoperative position of the component relative to the position of the true acetabulum. These results were somewhat better than those in other reports on cemented total hip replacement in young patients. The difference is probably related to the lower average weight and decreased activity level of patients with juvenile rheumatoid arthritis.

Activities of Daily Living↗

Evaluation of pyrantel pamoate, nitramisole and avermectin B1a against migrating Strongylus vulgaris larvae.

Trials were conducted in ponies to evaluate the efficacy of pyrantel pamoate (Strongid-T(R)) and two newer anthelmintics not yet commercially available, nitramisole and avermectin B(1)a, against migrating Strongylus vulgaris larvae. Ponies were removed from their mares within 24-48 hr after birth and reared in isolation, worm free. Between six and 14 weeks of age they were infected with 2000 or 2500 infective S. vulgaris larvae. Subsequently, they were monitored daily for clinical signs until the experiment terminated at 28 days postinfection. All ponies showed increased body temperature and reduced appetite within the first week of infection. All anthelmintics were administered on day 7 and in addition pyrantel pamoate was given on day 8 postinfection. The anthelmintics were in liquid formulation. Nitramisole and pyrantel pamoate were given by stomach tube and avermectin B(1)a by subcutaneous injection.Following administration of these compounds toxic reactions were not observed. All anthelmintics caused a reduction in body temperature and increased appetite and effected a clinical cure. In ponies which were not treated with an anthelmintic, temperatures remained elevated and appetites never returned completely to normal. These ponies also showed variable degrees of lethargy, depression, recumbency and colic and the majority died between two and three weeks postinfection. At necropsy, these control ponies showed variable degrees of adhesions involving the abdominal organs, necrosis of the ileum and cecum and severe arteritis and thrombosis of the major abdominal arteries and their branches.Although pyrantel pamoate, used at eight times the therapeutic dose for intestinal nematodes in the horse, effected a clinical cure it did not produce a radical cure. At necropsy, ponies treated with pyrantel pamoate had arteritis and thrombosis of the cranial mesenteric artery and its major branches. Nitramisole and avermectin B(1)a were able to effect both a clinical and radical cure.

Animals↗

Ambient oxygen tension modulates endothelial fibrinolysis.

PURPOSE: Vascular procedures reoxygenate ischemic endothelial cells (EC) and arterialize saphenous vein (HSV) EC. The balance between the EC-derived fibrinolytic components, plasminogen activator (tPA), and plasminogen inhibitor (PAI-1) contributes to maintaining thromboresistance. This balance also affects proteolysis through plasmin generation, mediating matrix metabolism endothelial migration, angiogenesis, and theoretically affecting the development of intimal hyperplasia. METHODS: To explore the impact of varying oxygen tensions on EC fibrinolysis, HSV and human umbilical vein (HUV) were subjected to Po2 of 40 mm Hg for 24 hours with restoration of Po2 to 150 mm Hg for 24 hours. The tPA and PAI-1 antigen and tPA/PAI-1 antigen ratio in conditioned media (CM), expressed as increases or decreases % change, normalized for cell count, versus controls, were analyzed by enzyme-linked immunosorbent assay. Cellular tPA and PAI-1 mRNAs were assessed by Northern analysis. RESULTS: The tPA but not PAI-1 was significantly decreased after the first 24 hours in HSVEC and significantly decreased after 48 hours in both HUVEC and HSVEC when compared with controls. Messenger RNA for tPA was unchanged but PAI-1 mRNA increased significantly for HSVEC and HUVEC after 24 hours of Po2 of 40 mm Hg, returning to baseline within 24 hours of Po2 to 150 mm Hg restoration. CONCLUSIONS: These data support the hypothesis of a fibrinolytic shift after altered ambient O2 tensions exposure in endothelium and demonstrate that HSVEC are more sensitive to altered O2 tension than HUVEC. Altered O2 tensions depress EC fibrinolysis in this model.

Atmospheric Pressure↗

Involvement of CD23/Fc epsilon RII in the homotypic and heterotypic cytoadhesion of the human eosinophilic cell line Eol-3.

A subclone of the EoL-3 human eosinophilic leukemia cell line (EoL-3.12) was selected for its high inducibility of CD23 (low affinity IgE receptor/Fc epsilon RII) by IL-4. Maximum membrane CD23 expression was detected after 16 h of incubation with IL-4, then gradually returned to basal level after 48 h. Membrane expression of CD23 on EoL-3.12 cells was found to parallel their homotypic aggregation. Extending the time of incubation with IL-4 to 48 h or more resulted in a de-aggregation of cells of cells with a shedding of membrane CD23 and an increase of its soluble form, sCD23. The IL-4-induced aggregation of EoL-3.12 cells was inhibited with anti-CD23 antibody or human myeloma IgE protein, indicating that it was mediated through the engagement of CD23. EoL3.12 incubated with IL-4 displayed morphological changes associated with differentiation, such as an increased number of lobulated nuclei with prominent nucleoli, increased ratio of cytoplasm and distinct cytoplasmic processes. EoL-3.12 cells incubated with IL-4 also displayed an enhanced adherence to human umbilical vein endothelial cells (HUVEC), which was reverted when the IL-4 incubation time extended. Furthermore, the transendothelial migration of EoL-3.12 cells toward a chemokinetic gradient of soluble CD23 (sCD23; 29 kDa fragment) closely paralleled the density of membrane CD23 expressed on EoL-3.12 cells. Additionally, the engagement of CD23 led to the activation of the L-arginine-dependent pathway of nitric oxide (NO) production, as detected by the increase in intracytoplasmic cGMP concentration. The capacity of EoL-3.12 cells to form homotypic as well as heterotypic adhesion appears therefore to be regulated, at least in part, by the level of CD23 expression.

Arginine↗

Increased plasma levels of stromal-derived factor-1 (SDF-1/CXCL12) enhance human thrombopoiesis and mobilize human colony-forming cells (CFC) in NOD/SCID mice.

OBJECTIVE: Stromal-derived factor-1 (SDF-1/CXCL12) is chemotactic for lympho/hematopoietic stem cells. We have previously shown that increasing peripheral blood (PB) levels of SDF-1 with adenovectors expressing human SDF-1 complementary DNA (ad-SDF-1) leads to hematopoietic stem cell mobilization as well as migration of megakaryocytes and thrombocytosis in mice. Herein, we studied the in vivo effects of ad-SDF-1 and of an analogue peptide of SDF-1 (CTCE-0214) on human hematopoiesis in a xenotransplant model. MATERIALS AND METHODS: Sublethally irradiated (300 cGY) NOD/SCID mice transplanted with human cord blood mononuclear cells (CB MNC) were injected with ad-SDF-1 (10(9) plaque forming units, i.v., x 1) or CTCE-0214 (10 mg/kg/dose, i.v. q 24 hours x 7). Effects on megakaryocytopoiesis (CD41+ cells and platelets) as well as stem cell mobilization were monitored. RESULTS: CB MNC in NOD/SCID mice are able to differentiate into CD41+ cells and platelets, peaking at week 9 at a mean of 3.7 x 10(3)/microL. i.v. injection of ad-SDF-1 increased human CD41+ cells by day 4 in PB and was followed by an increase in human platelet production by day 5, with return to baseline by day 30. Human colony-forming cells (CFC) were mobilized from bone marrow to spleen (by day 6-13) and to PB (by day 13). Human CD34+ and CD33+ cells were mobilized by this treatment as well. A novel SDF-1 peptide agonist (CTCE-0214) also mobilized human CFC and enhanced human thrombopoiesis. CONCLUSION: SDF-1 and its analogue may be of clinical value in stimulating platelet recovery after chemo/radiation treatment as well as in stem cell mobilization.

Adenoviridae↗

EGF receptors in R3230AC rat mammary carcinomas: characteristics and regulation in vitro and in vivo.

Epidermal growth factor (EGF), at 10(-11) M and 10(-10) M, stimulated [methyl-3H]thymidine incorporation into DNA and cell growth of R3230AC mammary adenocarcinomas in primary cultures, whereas at higher concentrations (10(-9) M and 10(-8) M) EGF inhibited DNA synthesis and cell growth in vitro. To determine whether these responses were receptor-mediated, 125I-EGF binding to freshly dissociated cells and primary cultures of R3230AC cells was measured and found to be time- and temperature-dependent. Specificity of EGF binding was demonstrated by 50% displacement occurring at an EGF concentration of 0.46 nM. Using 125I-EGF concentrations from 0.05 nM to 10 nM, saturable binding sites were documented; Scatchard analysis of these data produced curvilinear plots, suggesting the presence of high affinity (0.44-0.93 nM) and low affinity (1.5-4.8 nM) sites. 125I-EGF was rapidly internalized by cultured R3230AC tumor cells. By 30 min, 73% (25 degrees C) and 77% (37 degrees C) of total 125I-EGF was internalized (resistance to acid/salt extraction), whereas at 4 degrees C, cells internalized only 20% of EGF over a 3 hr incubation period. Following incubation with 125I-EGF for 2 hr at 4 degrees C, 25 degrees C, or 37 degrees C, the majority of cell-associated radioactivity eluted with intact 125I-EGF. However, when the material that dissociated from R3230AC cells after the 2 hr incubation was analyzed, 38% (25 degrees C) and 46% (37 degrees C) of the radioactivity migrated as lower molecular weight products, indicating that 125I-EGF was partially degraded intracellularly by R3230AC cells in primary culture. Pre-incubation of cells in primary culture with EGF (1-100 nM) for 30 min at 37 degrees C, led to "down-regulation" of EGF receptors; 1 nM EGF reduced the specific binding of 125I-EGF by 54% with higher concentrations (10 nM and 100 nM) reducing it further. Scatchard analysis of down-regulated cells showed a reduced number of high affinity binding sites with no change in the Kd of binding. Sialoadenectomy of rats had no effect on R3230AC tumor growth or EGF receptor levels in the tumor, liver, or uterus. Experiments to determine whether perturbations of the insulin milieu or ovariectomy would alter EGF receptors were performed. 125I-EGF binding was significantly elevated in tumors from diabetic rats (152% increase vs controls) and binding was returned to control (77% of intact rats) levels after administration of insulin to diabetic rats.(ABSTRACT TRUNCATED AT 400 WORDS)

Adenocarcinoma↗

Kallikrein-like amidase activity in renal ischemia and reperfusion.

We assessed a kallikrein-like amidase activity probably related to the kallikrein-kinin system, as well as the participation of leukocyte infiltration in renal ischemia and reperfusion. Male C57BL/KSJmdb mice were subjected to 20 or 60 min of ischemia and to different periods of reperfusion. A control group consisted of sham-operated mice, under similar conditions, except for ischemia induction. Kallikrein-like amidase activity, Evans blue extravasation and myeloperoxidase activity were measured in kidney homogenates, previously perfused with 0.9% NaCl. Plasma creatinine concentration increased only in the 60-min ischemic group. After 20 min of ischemia and 1 or 24 h of reperfusion, no change in kallikrein-like amidase activity or Evans blue extravasation was observed. In the mice subjected to 20 min of ischemia, edema was evident at 1 h of reperfusion, but kidney water content returned to basal levels after 24 h of reperfusion. In the 60-min ischemic group, kallikrein-like amidase activity and Evans blue extravasation showed a similar significant increase along reperfusion time. Kallikrein-like amidase activity increased from 4 nmol PNA mg protein-1 min-1 in the basal condition to 15 nmol PNA mg protein-1 min-1 at 10 h of reperfusion. For dye extravasation the concentration measured was near 200 microg of Evans blue/g dry tissue in the basal condition and 1750 microg of Evans blue/g dry tissue at 10 h of reperfusion. No variation could be detected in the control group. A significant increase from 5 to 40 units of DeltaAbs 655 nm g wet tissue-1 min-1 in the activity of the enzyme myeloperoxidase was observed in the 60-min ischemic group, when it was evaluated after 24 h of reperfusion. Histological analysis of the kidneys showed migration of polymorphonuclear leukocytes from the vascular bed to the interstitial tissue in the 60-min ischemic group after 24 h of reperfusion. We conclude that the duration of ischemia is critical for the development of damage during reperfusion and that the increase in renal cortex kallikrein-like amidase activity probably released from both the kidney and leukocytes may be responsible, at least in part, for the observed effects, probably through direct induction of increased vascular permeability.

Amidohydrolases↗

Hazards of imidacloprid seed coating to Bombus terrestris (Hymenoptera: Apidae) when applied to sunflower.

Seed coating treatments of sunflower by the systemic insecticide imidacloprid was suspected of affecting honey bees and bumblebees. The hypothesis raised was whether imidacloprid could migrate into nectar and pollen, then modify flower attractiveness, homing behavior, and colony development. Our greenhouse and field experiments with Bombus terrestris L. were aimed at the following: the behavior of workers foraging on treated and control plants blooming in a greenhouse, the homing rate of colonies placed for 9 d in a treated field compared with colonies in a control field, and the development of these 20 colonies under laboratory conditions when removed from the fields. In the greenhouse, workers visited blooming heads of treated and control plants at the same rate and the mean duration of their visits was similar. In field colonies, analysis of pollen in hairs and pellets of workers showed that in both fields 98% of nectar foragers visited exclusively sunflowers, whereas only 25% of pollen gatherers collected sunflower pollen. After 9 d, in the control and treated field, 23 and 33% of the marked foragers, respectively, did not return to hives. In both fields, workers significantly drifted from the center to the sides of colony rows. During the 26-d period under field and laboratory conditions, the population increase rate of the 20 colonies was 3.3 and 3.0 workers/d in hives of the control and treated field, respectively. This difference was not significant. New queens were produced in eight colonies in either field. The mean number of new queens per hive was 17 and 24 in the control and treated field, respectively. Their mating rate was the same. It was concluded that applying imidacloprid at the registered dose, as a seed coating of sunflowers cultivated in greenhouse or in field, did not significantly affect the foraging and homing behavior of B. terestris and its colony development.

Animals↗

Effects of WEB 2086, an antagonist to the receptor for platelet-activating factor (PAF), on PAF-induced responses in the horse.

Platelet-activating factor (PAF) causes oedema and neutrophil accumulation when injected into the skin of normal horses. PAF is also known to induce aggregation of horse platelets in vitro. The selective PAF receptor antagonist WEB 2086 has now been used to determine whether these effects are mediated by PAF receptor activation. Addition of WEB 2086 to equine platelets in vitro inhibited PAF-induced aggregation in a competitive reversible manner (pA2 = 7.14). Inhibition of in vivo inflammatory responses to PAF occurred after local administration of WEB 2086: wheal formation induced by 0.1 micrograms PAF/site was reduced by 1-10 micrograms WEB 2086/site. PAF (1 micrograms/site)-induced neutrophil accumulation was also inhibited by co-administration of 10 micrograms WEB 2086/site. Systemic administration of WEB 2086 (3 mg/kg iv) to 4 normal ponies inhibited PAF-induced wheal formation and ex vivo platelet aggregation. At 30 min after drug administration the concentration of PAF required to produce a half maximal aggregation response was increased 496 +/- 137 fold. At 6 h the degree of inhibition was markedly reduced and responses had returned to pre-treatment values by 24 h. PAF-induced increases in cutaneous vascular permeability were also reduced by 80% as early as 30 min after iv administration of WEB 2086 in these animals, the inhibition persisting for at least 6 h. These results suggest that in vitro and in vivo responses to PAF in the horse are mediated via activation to PAF receptors. WEB 2086 will therefore be a useful agent for studying the role of PAF in the pathogenesis of equine inflammatory conditions.

Animals↗

Counting Pakistanis in the Middle East: problems and policy implications.

"Using Pakistan as a case study, this article focuses on the difficulties of measuring both the outflow of workers over time and the stock abroad at any particular time. The various estimates of the number of Pakistanis in the Middle East are evaluated and an alternative estimate is provided based on hitherto unused data from two major surveys of returning workers. The alternative estimate differs substantially from the others, the difference being attributed principally to clandestine worker immigration. The concluding section discusses the policy implications of inaccurate information about the numbers of workers abroad and the likely effects of the current Persian Gulf crisis on Pakistan's economy."

Asia↗

A longitudinal study on different models of postabortion care in Tanzania.

OBJECTIVE: To identify women having unsafe abortions and elucidate whether an acceptable follow-up rate among these women can be retrieved. STUDY POPULATION: One thousand three hundred and fifty-seven women attended Temeke Municipal Hospital, Dar es Salaam with an abortion-related diagnosis. METHODS: Women having unsafe abortions were identified by an empathetic dialogue, offered a contraceptive service and asked to return for follow-up. Three different ways of achieving follow-up information were tested. In phase 1, a combination of hospital-based and home-based interviews was utilized, in phase 2, an additional 1-month control visit was added to the protocol, and in phase 3, the contraceptive counseling and service was provided by technically well-skilled counselors. RESULTS: Seven hundred and eighty-eight women were identified as having had unsafe abortions and 491 women as spontaneous abortions. Women having unsafe abortions were younger, more often single and of higher parity than women having spontaneous abortions. The follow-up rate achieved varied from 47%-72%, being lowest in phase 1 and highest in phase 3. The two most common reasons for loss to follow-up were the interviewer's inability to locate the respondent's house either because of an unspecific or a remote address (58%) and migration (29%). CONCLUSION: If hospital-based and confidential home-based interviews are used combined and if the women having unsafe abortions are counseled by technically well-skilled counselors, it is possible to achieve a reasonable follow-up rate among women having unsafe abortions.

Abortion, Induced↗

Isolation and characterization of alpha 1-acid glycoprotein from horses, and its evaluation as an acute-phase reactive protein in horses.

Equine alpha 1-acid glycoprotein (alpha 1AG) was isolated from equine serum by successive ammonium precipitation, anion- and cation-exchange chromatographies, and gel filtration. Purified equine alpha 1AG had a molecular weight of 46,000 +/- 1,000, and contained 31.4% carbohydrate. Gel isoelectric focusing revealed an isoelectric point range of 2.8 to 3.7. With immunoelectrophoresis, it was found that alpha 1AG migrated to the alpha 1-globulin region. Single radial immunodiffusion was used for quantitative measurement of alpha 1AG in equine serum. In clinically normal foals, serum alpha 1AG was undetectable (less than or equal to 20 micrograms/ml) in less than or equal to 7-day-old foals, but was detected by 14 days. The alpha 1AG concentration (mean +/- SD) increased to reach mean adult values of 99.23 +/- 26.90 micrograms/ml by 1 year of age. The alpha 1AG concentration in pregnant mares decreased at 2 to 3 months before parturition, then gradually increased until 1 day after parturition, when a brief decrease was observed. The concentration increased again at 2 weeks after foaling, then a decrease was observed, after which the alpha 1AG concentration increased again by 2 to 4 months after parturition. The concentration of serum alpha 1AG quickly rose to peak values 2 to 3 days after castration and jejunojejunostomy in adult horses, returning to baseline values by 14 to 28 days after surgery. The alpha 1AG was concluded to be an acute-phase reactive protein in horses.

Acute-Phase Reaction↗

The demographics of unfunded pensions.

The performance of pay-as-you-go old-age insurance under different demographic conditions can be estimated from a metric consisting of the implicit rate of return to successive cohorts. The author shows a positive return for the prospective population over the next few years, but for cohorts born after the end of the century returns will become sharply negative. A decline in returns is typical of pay-as-you-go schemes as they mature, and a change to negative returns is typical in particular as the birth rate falls under fixed economic conditions. The return can be kept positive by greatly increased fertility or immigration. Taking labor-force participation rates into account, and supposing entitlement independent of contribution, gives much larger negative rates of return, however. The main calculations considered here are for schemes with a constant pension. If the contribution rather than the pension is kept constant then the disparities between cohorts with respect to their returns are smaller, and although the negative returns for future generations then set in earlier they are smaller. The conclusions of the paper are broadly applicable to any population that showed a baby boom after World War II and replacement-level or lower fertility subsequently.

Americas↗

Transient membrane shedding in Limulus photoreceptors: control mechanisms under natural lighting.

Photoreceptors of the Limulus lateral eye shed their light-sensitive membranes (rhabdoms) in a burst early each morning when the animal is maintained in natural lighting. This shedding burst produces a cloud of multivesicular bodies which coalesce and migrate away from the rhabdom. Within 24 hr, these gradually collapse to combination bodies and ultimately to lamellar bodies. Light initiates the burst of shedding. If animals are maintained in darkness beyond their normal dawn, the shedding burst is delayed until the first onset of light. We have not been able to produce a second burst of membrane shedding within one 24-hr period. Efferent optic nerve activity generated by a circadian clock in the brain primes the shedding burst. At least 3 hr of efferent activity in darkness must precede light onset to prime membrane shedding; however, the efferent fibers need not be active when the light-initiated burst occurs. Chronically blocking the efferent input to the retina abolishes the shedding burst. The burst of membrane shedding is robust and short-lived. Within 15 min of light onset the area of photosensitive membrane decreases by about 70%, and within an hour the rhabdom returns to essentially its preburst size. At other times in the diurnal light cycle, the size of the rhabdom undergoes significant variations which are not abolished by blocking the efferent input. Apparently the daily burst of shedding overlays a second cycle of membrane metabolism that is not controlled by efferent optic nerve activity.

Animals↗