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PubMed2002

Fluorine-18 labeled mouse bone marrow-derived dendritic cells can be detected in vivo by high resolution projection imaging.

Immunization with ex vivo generated dendritic cells has become a focus for many clinical applications. The optimal site of injection and the migration pattern of these cells remain to be elucidated. We therefore developed a novel method for labeling mouse bone marrow-derived dendritic cells (BMDC) with the positron emitting radioisotope F-18 using N-succinimidyl-4-[F-18]fluorobenzoate, which covalently binds to the lysine residues of cell surface proteins. When we determined the stability of F-18 labeled BMDC, we found that at 4 h only 44+/-10% of the initial cell-bound activity was retained at 37 degrees C, whereas considerably more (91+/-3%) was retained at 4 degrees C. Labeled cells did not exhibit any significant alteration in cell viability or phenotype as determined by trypan blue exclusion and FACS analysis 24 h after radiolabeling. Furthermore, F-18-labeled BMDC stimulated allogeneic T cells in a mixed leukocyte reaction as potently as did sham-treated BMDC and migrated towards secondary lymphoid tissue chemokine (SLC) in a chemotaxis assay in vitro with the same efficiency as sham-treated BMDC. Migration of F-18-labeled BMDC was studied after footpad injection by (1) ex vivo counting of dissected tissues using a gamma counter and (2) in vivo by imaging mice with PiPET, a 2-mm resolution positron projection imager. After 4 h, the ratio between measured activity in draining vs. contralateral (D/C) lymph nodes (LN) was 166+/-96 (n=7) in the case of live cell injections, whereas if we injected heat-killed F-18-labeled BMDC or F-18-labeled macrophages the D/C ratios were 17+/-2 (n=2) and 14+/-4 (n=2), respectively. Injection of cell-free activity in the form of F-18-labeled 4-fluorobenzoic acid resulted in a D/C ratio of 7+/-2 (n=3), suggesting that the activity measured in the draining lymph node was associated with migrated F-18-labeled BMDC. When F-18-labeled live cells were injected into the footpad, 0.18+/-0.04% (n=7) of footpad activity was found in the draining LN within 4 h, whereas none was found in the contralateral LN. Quantitative assessment of cell migration by PET projection imaging of mice confirmed the ex-vivo counting results. These studies indicate that PET imaging offers a new approach for in vivo studies of dendritic cell biodistribution and migration.

Animals↗
PubMed1998

Macrophage behavior associated with acute and chronic exposure to HIV GP120, morphine and anandamide: endothelial implications.

We demonstrate that immediate exposure to gp120 (5 min; 0.1 microg/ml) results in a significant shift of the macrophage population to an amoeboid and motile category (P<0.01; 91.7+/-5.5 vs. a control value of 42.4+/-4.2) and prior exposure with anti-gp120 antagonizes this shift. Acute exposure of the macrophages to morphine (10(-6) M) or anandamide (10(-6) M) resulted in the cells rounding up (shape factors of 0.84 and 0.87 respectively) and becoming non-motile. The action is blocked by prior treatment with the specific antagonists naloxone and SR 141716A. Chronic exposure (6 h) of the cells to all three agents resulted in a random migration pattern. Further, all agents blocked chemotaxis induced by DAMA and IL-1. Observation of the cells behavior during chronic exposure revealed a sporadic activity pattern with gp120 whereas morphine and anandamide first induced a period of inactivity which is followed by a period of activity (chemokinesis). Recent work from our laboratory has demonstrated that both morphine and anandamide acutely stimulate constitutive macrophage nitric oxide (NO) release, which then induces macrophage rounding and inactivity. It was therefore of interest to examine their behavior by exposing macrophages to the NO-donor SNAP. In a concentration dependent manner SNAP exhibited the same behavioral actions as both substances of abuse. Given this, we next determined if macrophages exposed to gp120 would release NO. We demonstrated that NO was released only when exposed to morphine and anandamide not gp120. Thus. the chemokinetic inducing activities of these agents may be the basis for excitotoxin liberation in neural tissues and/or a higher viral load in various organ systems since cellular adherence and random migration are stimulated.

Analysis of Variance↗
PubMed1988

Application of a mathematical model to South African migration data, 1975-1980.

The author applies the Rogers and Castro model of migration to data for South African whites. "South African migration patterns of whites for the period 1975-1980, as obtained from census data, correspond in general with those observed in most other developed countries and the mathematical model of Rogers and Castro could thus be applied. Quantitative values have been found for the various parameters defined by Rogers and Castro."

Africa↗
PubMed1982

Genetic relatedness among human rotaviruses as determined by RNA hybridization.

Viral RNAs from human rotaviruses were compared by gel electrophoresis and by hybridization to probes prepared by in vitro transcription of two well-characterized laboratory strains (Wa and DS-1). Also, the viral RNAs were compared by hybridization to probes prepared from three of the test viruses. Thirteen specimens (diarrheal stools) were obtained from infants and children 5 to 21 months old on a single day at the emergency ward of the Caracas Children's Hospital, and an additional specimen was obtained from the same hospital 6 months before. When the electrophoresed viral RNAs were stained with ethidium bromide and examined by UV light, five different migration patterns (electropherotypes) were distinguished on the basis of differences in mobility of the RNA segments. The hybridization technique that was employed permitted only qualitative comparisons of corresponding genes of different human rotaviruses. Ten of the specimens contained enough virus to yield sufficient RNA for hybridization studies. Eight of the viruses studied by hybridization contained 4 to 11 genes that reacted specifically with the Wa probe to yield double-stranded RNA segments with a mobility similar to that of Wa viral RNA or test virus RNA. The other two viruses contained 11 genes that reacted specifically with the DS-1 hybridization probe to yield double-stranded RNA segments with a mobility similar to DS-1 viral RNA or test virus RNA. A more complex picture emerged when hybridization probes were prepared from three of the test viruses and used to compare the different electropherotypes. Corresponding genes that exhibited similar migration did not necessarily exhibit homology when studied by hybridization. Also, some corresponding genes that exhibited homology did not have the same mobility by gel electrophoresis.

Child, Preschool↗
PubMed2006

Comparative analysis of hazardous household waste in two Mexican regions.

Household hazardous waste (HHW) generation in two Mexican regions was examined, a northern region (bordering with the USA) and a central region. The aim of this work was to determine the dynamics of solid waste generation and to be able to compare the results of both regions, regarding consumption patterns and solid waste generation rates. In the northern region, household solid waste was analysed quantitatively. In order to perform this analysis, the population was categorized into three socioeconomic strata (lower, middle, upper). Waste characterization revealed the presence of products that give origin to household hazardous waste. In the northern region (Mexicali city), household hazardous waste comprised 3.7% of municipal solid waste, the largest categories in this fraction were home care products (29.2%), cleaning products (19.5%) and batteries and electronic equipment (15.7%). In the central region, HHW comprised 1.03% of municipal solid waste; the main categories in this fraction were represented by cleaning products (39%), self care products (27.3%), and insecticides (14.4%). In Mexicali, the socioeconomic study demonstrated that the production of HHW is independent of the income level. Furthermore, the composition of the solid waste stream in both regions suggested the influence of another set of variables such as local climate, migration patterns and marketing coverage. Further research is needed in order to establish the effect of low quantities of HHW upon the environment and public health.

Environmental Pollution↗
PubMed2001

Extraintestinal migration of Pharyngostomum cordatum metacercariae in experimental rodents.

Extraintestinal migration patterns of Pharyngostomum cordatum (Digenea: Neodiplostomidae) were studied in experimental rodents such as mice, rats, and hamsters. When metacercariae isolated from grass snakes were infected orally to rodents, they penetrated the intestinal wall at days 2-3 post-infection (p.i.) and were discovered mainly in the diaphragm, intercostal muscles, and vital organ such as the lungs at days 7-28 p.i., without morphological changes. Interestingly, from several rodents which died suddenly at days 2-9 p.i., small to considerable numbers of metacercariae were found, not only in the lungs, but also in the heart and brain. Within the tissues, worms were freely motile until day 7 p.i., but later they were surrounded by host cells, and finally tissue cysts were formed. When metacercariae harvested from the snakes and intercostal muscles of rodents were infected orally to cats, they developed into adult flukes in the small intestine. The results show that P. cordatum undergoes considerable extraintestinal migration including the vital organs of its rodent hosts.

Animals↗
PubMed1995

[The social geography of AIDS in Brazil].

The first of a series of papers concerning the evaluation of the dynamics of the AIDS epidemic in Brazil employing techniques of geographical analysis, is here presented. Results of research undertaken in the US (especially in New York City) are compared with those of a recent investigation carried out in the city of S.Paulo, Brazil (Grangeiro, 1994). In both, geographical patterns of socio-demographic variables correlate with different patterns of the spread of the AIDS epidemic through the transmission groups. Recent trends of the AIDS epidemic in Brazil: the displacement toward medium sized cities and expansion frontiers, increasing report of AIDS cases among the poor and underprivileged, changes in the pattern of transmission with proportional augmentation of heterosexual transmission and IDUs as transmission groups, are described and analysed. The geographical distribution of the AIDS cases registered between 1987-1993 in Brazil throughout the Brazilian States is evaluated by means of worksheets, maps, and non-parametric statistics. Results show that Gravimetric Centers (obtained by the use of the calculus spatial means) of AIDS in Brazil are situated within a triangle the sides of which are formed lines joining the three main metropolitan areas of the wealthiest region of Brazil--the southeast, i.e. São Paulo, Rio de Janeiro and Belo Horizonte. These especially S. Paulo, function as points of attraction for these Gravimetric Centers (GCs) towards the south as compared with the GCs of the general population calculated ia accordance with data from the 1980 and 1991 censuses. It is possible to observe a displacement of the GCs toward the northwest over this period in accordance with the migration patterns of the Brazilian population in general, though with a dynamic of its own. These changes in the geographical, socio-demographic and transmission group patterns show the complex nature of the epidemic in Brazil and pose additional difficulties for the development of prevention strategies.

Acquired Immunodeficiency Syndrome↗
PubMedDate not supplied

The prolonged epidemic of anthroponotic cutaneous leishmaniasis in Kabul, Afghanistan: 'bringing down the neighbourhood'.

In order to investigate the distribution and causes of the spread of anthroponotic cutaneous leishmaniasis (ACL) in Kabul, Afghanistan, a cross-sectional study was conducted during 1997-98 amongst 75,787 residents in the 13 central districts of the city. Using data on active lesions and scars with their times of onset, migration patterns and age of subjects, 2 independent methods were used to estimate, retrospectively, the annual incidence of ACL in recent years. Results indicated a rapid increase in incidence from 1987, peaking in 1996 when an estimated 12% of the population had active disease. Active prevalence was lowest in infants (aged < 2 years), and while risk was gender-independent in children and adolescents, active prevalence in those aged > 20 years was significantly higher amongst females than males (odds ratio [OR] = 1.51, 95% CI 1.34-1.70). About 44% of lesions were located on the head, 38% on upper limbs, 16% on lower limbs and 2% elsewhere. The relative frequency of head lesions dropped with age (P < 0.001), and amongst adults was lowest amongst males (P < 0.001), possibly due to the protective effect of a beard. Within the study population, 32% reported that they had immigrated from outside Kabul, 34% that they had been born in Kabul but had since migrated to another district of the city, and 34% that they had been born in the district of their present residence. Active prevalence amongst those born in their current district of residence was positively associated with the percentage of immigrants in their district (P = 0.027), indicating that a 1% increase in the percentage of immigrants increased the odds of an active lesion by 12% (OR = 1.12, 95% CI 1.01-1.24), but there was no association with the percentage of migrants from other districts in Kabul (P = 0.65) or with war damage (P = 0.33). As active prevalence was not significantly greater in immigrants than local Kabulis, these results support the hypothesis that the epidemic in Kabul has been maintained by a steady influx of susceptible immigrants. It is important that the new opportunities for social development that now exist in Kabul are not hampered by this unpleasant and stigmatizing disease. As population movement is clearly a contributing factor to its transmission, this threat is very real.

Adolescent↗
PubMed1993

Current trends and patterns of female migration: evidence from Mexico.

"This study uses a new source of data to assess trends and patterns of female migration from Mexico. Data were collected from migrants interviewed in ten Mexican communities from 1987 through 1990, as well as from outmigrants from those communities who were later located in the United States. The first part of the analysis examines changes in migrant behavior throughout the 1980s by estimating trends in the probability of first-time and repeat migration and by assessing the impact of the Immigration Reform and Control Act (IRCA) on these trends.... The study then considers the determinants of female Mexican-U.S. migration by examining whether and how women's recent moves reflect their personal characteristics, the resources in their households, or a process of family reunification." This paper was originally presented at the 1992 Annual Meeting of the Population Association of America.

Americas↗
PubMed1991

X-chromosome inactivation in the liver of female heterozygous OTC-deficient sparse-furash mice.

X-chromosome inactivation patterns were investigated in livers of nine spfash female heterozygous ornithine transcarbamylase (OTC)-deficient mice. Quantitative morphometric analysis of cellular mosaicism was performed on sections of frozen liver reacted with purified anti-OTC antibody and prepared for immunofluorescent microscopy. Analysis of enzymatic OTC activity was performed on sections of these livers using a radiochromatographic technique. Several areas of cellular mosaicism were seen in each of the histological sections that were studied. The distribution of the volume fraction of the liver tissue cells having cells with normal OTC content among the nine mice ranged from 20 to 70% and it correlated (r = 0.8, P = 0.005) with the enzymatic activities of the respective livers. The extreme variegation of mosaic patches in the liver suggests the high probability that a single needle biopsy will be diagnostic in females heterozygous for an OTC mutation. This study also suggests that at the time of X inactivation, the number of primordial liver embryonic cells is small and the observed variegation of liver mosaicism probably results from complex migration patterns of liver cells during fetal development. This study shows that the spfash mouse is a suitable animal model for quantitative studies of X-chromosome inactivation in liver using immunohistochemical staining of OTC protein.

Animals↗
PubMed1991

Colonic motility in innervated and extrinsically denervated loops in dogs.

The control mechanism of canine colonic motor activity measured by means of chronically implanted force transducers was studied by comparing diurnal changes and migrating patterns in control dogs and dogs with innervated and extrinsically denervated colonic loops. Five force transducers (C1-C5) were placed on the colon, and the middle colon was transected to construct a loop including C2 and C3 transducers. Colonic continuity was established by an end-to-end anastomosis. In the fasted state, colonic motor complexes of 8-13 minutes' duration were observed to occur at intervals of 22-32 minutes in all three groups, but response to feeding was clearly different; significant enhancement of the colonic motor indexes lasting for 8-16 hours after feeding, which was observed at all recording sites in control dogs, was identified only in the proximal and distal colon in dogs with innervated and extrinsically denervated loops. In the innervated loop, significant enhancement of the motor indexes was observed only in the first 2 hours after feeding. In the extrinsically denervated loop, feeding did not induce any response. In both groups with loops, greater than 40% of the motor complexes that occurred in the proximal colon migrated to the distal colon directly across the anastomosis and less than 20% propagated to the loop. In addition, the migration time between the proximal and the distal colon was greatly reduced in both groups with loops compared with that in the control group. Another change observed within the loop was an increase in numbers of retrograde migrating colonic motor complexes. It is concluded that colonic motor activity is under the predominant control of intraluminal contents in the digestive state but that extrinsic nerves may play an important role in the response observed in the innervated loop in the first 2 hours after feeding, which should be defined as the gastrocolonic response in dogs. In the interdigestive state, the intrinsic nervous system and/or humoral factors may control the occurrence of colonic motor complexes.

Animals↗
PubMed2000

Effect of maternal and paternal line on spatial and temporal marine distribution in Atlantic salmon.

We examined the inheritance of the sea migration pattern of Atlantic salmon, Salmo salar, in a crossing and tagging experiment in the Baltic Sea. Individuals from the parental stocks, Neva and Iijoki, and their reciprocal hybrids were released as 2-year-old smolts, into the same estuary of the Bothnian Sea in 1994. Two thousand smolts from each of the four groups were marked with Carlin tags. The recapture rate of the tags was nearly 10%. We used log-linear models to analyse the marine distribution of the salmon groups from the tag recovery data. The pure stocks and their pooled hybrid groups all showed statistically significant differences between each other in spatial and temporal sea distribution. The Iijoki salmon were more frequently (9%) caught outside the Bothnian Sea than were the Neva salmon (2%). The majority of the Iijoki salmon (55%), but fewer Neva salmon (40%), were caught in the second sea year. In spatial distribution, the hybrids seemed to be intermediate between the parental stocks, with no differences between reciprocal female and male lines. In duration of sea migration and age at maturity, however, the hybrids were very similar to their maternal line, the effect of which was thus clearly stronger than that of the paternal line. Copyright 2000 The Association for the Study of Animal Behaviour.

Journal Article↗
PubMed1998

Comparison of glycosylation patterns of phytase from Aspergillus niger (A. ficuum) NRRL 3135 and recombinant phytase.

The glycosylation patterns of phytase (E C 3.1.3.8) from Aspergillus niger NRRL 3135 with recombinant phytase from A. niger van Tieghem were compared. The following characteristics were studied: size of the whole molecule, type of linkage (N-linked or O-linked oligosaccharide), profile (number of different type of oligosaccharides present), monosaccharide composition, their order, and configuration. The molecular weights of both glycoproteins, after deglycosylation, was approximately 55 kDa as determined by SDS-PAGE. Both glycoproteins were about 35.29% glycosylated (calculations were made on the basis of 85 kDa molecular weight before deglycosylation). Only N-linked oligosaccharides were present. When N-linked oligosaccharides were released and labeled, the same profile was obtained for both glycoproteins. Mannose residues were detected after digestion by combinations of various exoglycosidases. N-acetylneuraminic acid, galactose, and N-acetylglucosamine residues were not detected. Released mannose residues were (alpha 1-2,3,6) linked. The trisaccharide core structure was nonfucosylated for all the oligosaccharides released from both glycoproteins. The only major difference found between the two glycoproteins was the migration pattern of oligosaccharide bands on gel after digestion with alpha-mannosidases. The structure of N-linked oligosaccharides ranged from (Man)5(GlcNAc)2 to (Man)10 (GlcNAc)2.

6-Phytase↗
PubMed1996

Internal migration in China, 1950-1988.

This paper examines the long-term patterns of migration within China between 1950 and 1988. The analysis uses data from China's 1988 2/1,000 Fertility and Birth Control Survey, which asks respondents about their most recent interprovincial move. The results suggest that long-term migration patterns can be explained by political and economic changes in China. We argue that the approaches we introduce can offer significant insight into long-term migration patterns for countries where historical data on migration are unavailable or unreliable.

China↗
PubMedDate not supplied

Residency patterns and secondary migration of refugees.

"This paper synthesizes available research regarding the residency patterns of refugees in the United States." Consideration is given to the impact of policy on residency patterns and to the effect of secondary migration on the geographic distribution of refugees. "The first section of the paper presents an historical background to this issue, tracing the evolution of U.S. policy and outcomes from 1945 to the start of the Indochinese resettlement program in 1975. The second part focusses upon the residency patterns of the 1975 Indochinese arrivals, and the third section deals with refugees who have arrived since 1979."

Americas↗
PubMed1998

Endothelial cell adhesion molecule and PMNL response to inflammatory stimuli and AGE-modified fibronectin.

BACKGROUND: Atherosclerotic vascular disease is the leading cause of death in patients with diabetes mellitus and end-stage renal disease. Advanced glycation end products (AGEs) are strongly suggested to be involved in the pathogenesis of atherosclerosis in these patients who also frequently experience infectious complications. We hypothesized that the interaction of AGEs and inflammatory mediators contributes to the up-regulation of endothelial cell activation. METHODS: We investigated the effect of advanced glycated fibronectin in the presence or absence of inflammatory stimuli on the endothelial cell surface and mRNA expression of cell adhesion molecules. Furthermore, the influence of advanced glycated fibronectin on the transendothelial migration pattern of polymorphonuclear cells was analyzed. RESULTS: Exposure to advanced glycated fibronectin together with inflammatory stimuli such as interleukin (IL)-1alpha, tumor necrosis factor-alpha (TNF-alpha) or lipopolysaccharide (LPS) led to a significant increase in the surface expression of the cell adhesion molecules E-selectin, ICAM-1, VCAM-1 and PECAM-1 on endothelial cells. Soluble AGEs in combination with advanced glycated fibronectin significantly enhanced the endothelial cell surface expression of ICAM-1, VCAM-1 and PECAM-1, whereas this was not the case for E-selectin. At the transcriptional level short-time exposure of endothelial cells to advanced glycated fibronectin and inflammatory mediators resulted in an increased expression of E-selectin, ICAM-1 and VCAM-1 mRNA levels, whereas PECAM-1 repeatedly showed a significant decrease of gene transcript levels. An increase of mRNA levels was also observed for E-selectin, ICAM-1, VCAM-1 and PECAM-1 following incubation with a combination of advanced glycated fibronectin and soluble advanced glycation end-products. Furthermore, polymorphonuclear cells responded with a sevenfold increase in transendothelial migration following exposure of endothelial cells to advanced glycated fibronectin and inflammatory mediators. CONCLUSIONS: These results suggest that the combination of matrix glycation and inflammation up-regulates the activation of the endothelial cell adhesion cascade, a mechanism that might contribute to the increased burden of atherosclerotic morbidity and mortality in patients suffering from diabetes mellitus or chronic renal failure.

Albumins↗
PubMed1989

A new congenital platelet abnormality characterized by spontaneous platelet aggregation, enhanced von Willebrand factor platelet interaction, and the presence of all von Willebrand factor multimers in plasma.

A case is reported of a 49-year-old woman with a mild bleeding tendency. Her bleeding time, platelet count and size, plasma ristocetin cofactor activity, von Willebrand factor (vWF) antigen, and vWF multimeric pattern are all within normal limits. Spontaneous platelet aggregation is observed when citrated platelet-rich plasma (PRP) is stirred in an aggregometer cuvette. This aggregation is completely is only slightly diminished by an antiglycoprotein (GP) IIb/IIIa or by an anti GPIb monoclonal antibody. The patient's PRP shows increased sensitivity to ristocetin. The distinct feature of this patient, also present in two family members studied, is that platelet aggregation is initiated by purified vWF in the absence of any other agonist. The vWF-induced platelet aggregation is abolished by anti-GPIb and anti-GPIIb/IIIa monoclonal antibodies and by EDTA (5 mmol/L). Apyrase inhibits the second wave of aggregation. Patient's platelets in PRP are four to six times more reactive to asialo vWF-induced platelet aggregation than normal platelets. The amount of radiolabeled vWF bound to platelets in the presence of either low concentration of ristocetin or asialo vWF was increased 30% compared with normal. The patient's platelet GPIb was analyzed by SDS page and immunoblotting and by binding studies with anti-GPIb monoclonal antibodies showed one band with slightly increased migration pattern and a normal number of GPIb molecules. Unlike the previously reported patients with pseudo or platelet-type von Willebrand disease, this patient has normal vWF parameters.

Antibodies, Monoclonal↗
PubMedDate not supplied

Marriage behaviour in the Alpine Non Valley from 1825 to 1923.

BACKGROUND: The study is part of a research project on the marital structure of mountain populations from the Eastern Italian Alps. Little is known about marriage patterns in this Alpine area. AIM: The aim of the study is to evaluate the extent of reproductive isolation in some communities of the Non Valley (Trentino, Italy) and to investigate its microgeographic and temporal changes over the period 1825-1923. SUBJECTS AND METHODS: 4518 microfilmed marriage records from registers of seven parishes of the Non Valley were used to analyse the following: endogamy rate, inbreeding calculated both from dispensations and from isonymy, repeating pairs of surnames in marriages, isonymic relationships. RESULTS: The results show notable variability among parishes in the levels of endogamy (40-73%), inbreeding (alpha: 1.9-4.57; Ft: 0.0073-0.019) and subdivision (RPr/RP: 0.5-1.3). The values are relatively stable over the course of a century, apart from a rise in inbreeding indicated by dispensations and a slight decrease of endogamy at the beginning of the 20th century. Isonymic relationships reflect geographic proximity between populations, with minimum changes through time. CONCLUSIONS: Variations in the level of reproductive isolation within the Non Valley are consistent with the different geographic characteristics and population sizes of the settlements. Comparison with data obtained from previous studies in the Eastern Italian Alps shows that the values of the investigated biodemographic indicators are in line with the geography and altitude of the area. The slight differences in temporal trend of endogamy and inbreeding can be correlated with different migration patterns.

Consanguinity↗