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PubMed1977

Cells and immunoglobulins in lymph.

Studies of the free-floating lymphocytes and of the immunoglobulins in lymph collected over long periods of time from ducts draining individual tissues of the body as well as from the thoracic duct of the fetus in utero have been reviewed. The findings show that stimuli within the internal milieu act on different classes of lymphocytes to alter their migration pattern, morphology, metabolic activity, and range of immunological potentialities. As the lymphoid cells migrate between the blood, tissue fluid, and lymph, a continual process of reassortment occurs leading to the establishment of heterogeneous lymphoid cell populations in different regions of the lymphatic apparatus. It seems that the biological activities of these cells are not decided only in terms of a thymus or a bone-marrow origin. The immunoglobulins, like other proteins in lymph, are mainly derived by filtration from the circulating plasma. Some of the immunoglobulins and specific antibodies are synthesized, however, by lymphoid cells and secreted directly into the lymph.

Antibody-Producing Cells↗

PubMed1994

Cellular interactions and adhesion molecules in psoriatic skin.

T-cell activation probably plays the most important role in hyperproliferation of keratinocytes in psoriasis. We present here our results concerning the interacting immunocompetent cells and their phenotypic and functional characteristics in relation to psoriasis pathology. Immunohistochemical analysis of skin biopsies from psoriasis patients, did indeed show that hyperproliferation of keratinocytes is associated with increased vasculature and increased influx of MHC class II molecules expressing immunocompetent cells. Furthermore, in psoriasis, several adhesion molecules and other relevant activation markers were found to be upregulated even in the non-lesional psoriatic skin, indicating that psoriatic skin in general is in an activated state. This interpretation is further supported by the observation that the expression of several AR and other relevant activation markers when compared with those in non-lesional skin from contact dermatitis are increased in a significant manner in the non-lesional skin of psoriasis patients. We have then followed up our investigations by generating T-cell lines from lesional psoriatic skin and studied their adhesion patterns on cultured endothelial cells in order to get better insight into the migration pattern of different T cell subsets in psoriasis pathology. Our results indicate that different T-cell subsets CD4+, CD8+ (both TCR-alpha beta+) CD4-/CD8+ TCR-gamma delta+ and CD4-CD8-TCR-gamma delta (V delta 1-) T-cells can easily be generated from psoriatic patients. In a comparative kinetic study using unstimulated and stimulated cultured human umbilical vein endothelial cells, we observed that TCR-gamma delta T cells showed different adhesion properties from that of TCR-alpha beta+ T cell subsets.(ABSTRACT TRUNCATED AT 250 WORDS)

Cell Adhesion↗

PubMedDate not supplied

Evidence of an increasing AIDS burden in rural America.

As the AIDS epidemic has matured in the United States, the characteristics of affected populations have shifted from a predominantly white homosexual/bisexual population to one now including increasingly more minorities, injecting drug users and women. Concomitant with the changing nature of persons diagnosed with AIDS there has been an increasing proportion of AIDS cases diagnosed in non-metropolitan areas. Both AIDS incidence and mortality data suggest a possible shift in AIDS from urban to rural areas, and from coastal to interior parts of the country. Migration of persons with AIDS may be contributing to this shift. National strategies for prevention and treatment of AIDS should consider taking into account the geographic behavior of this epidemic. The analysis addresses this issue by summarizing current knowledge regarding the spread of AIDS in rural areas, describing the urban-rural migration patterns from a major U.S. urban epicenter and presenting new NYC data on migration of people with AIDS and previously unpublished AIDS mortality data by state.

Acquired Immunodeficiency Syndrome↗

PubMed1994

Allelic D variants of transferrin in evaluation of alcohol abuse: differential diagnosis by isoelectric focusing-immunoblotting-laser densitometry.

In the diagnosis of alcohol abuse transferrin (Tf) allelic D variants generate false-positive test results for carbohydrate-deficient transferrin (CDT) as assessed by their electrophoretic migration patterns. The predominant Tf C1 allele encodes a protein for which the most prevalent isoform has a pI of 5.4, i.e., four sialic acids and two bound ion molecules. Carriers of allele D encode Tfs with different amino acid sequences, for which the pI is > 5.7, despite their identical iron and carbohydrate composition. We used isoelectric focusing, immunoblotting, and laser densitometry (IEF-IB-LD) to distinguish Tf D variants from CDT. Alcohol abusers carrying the D chi allele tested CDT+; D chi nondrinkers were CDT-. Although normal controls (< 15 g of alcohol per day for 7-10 consecutive days) carrying variants D1, D2, or D chi exhibited abnormal IEF banding patterns, they did not generate false-positive results for CDT. D3 variants expressed isoforms that migrate at the same pI as CDT bands. Thus, IEF-IB-LD yields a highly resolved banding pattern to distinguish most Tf D variants from CDT.

Alcoholism↗

PubMed1997

Prevalence and characteristics of severe rotavirus infections in Nicaraguan children.

We analyzed the prevalence of rotavirus in 296 children age between 3 and 36 months who were hospitalized in 1994 with severe gastro-enteritis at two health centres for diarrhoea treatment in León, Nicaragua. Enteric viruses were detected in 96 (32.4%) of the children and rotaviruses were the most common pathogens detected in 84 (28%). The majority of rotavirus infections occurred in children less than 1 year old and all strains isolated belonged to subgroup II and had 'long' RNA patterns. Molecular epidemiology of 55 rotavirus strains revealed that all had the same RNA migration pattern and serotyping of 37 strains by PCR technology revealed that all isolates belonged to serotype 3. A significant observation was that only one electropherotype of rotavirus circulated. No non-group A rotaviruses were found by RNA gel electrophoresis. Adenoviruses were found by ELISA in 14 of 265 (5%) children and were most frequently detected during the 1st year of life. Of 103 faecal samples analyzed by electron microscopy, four contained small round structured viruses.

Adenovirus Infections, Human↗

PubMedDate not supplied

Analysis of the rhodopsin and peripherin/RDS gene in two families with pattern dystrophy of the retinal pigment epithelium.

Mutations of the peripherin/retinal degeneration slow (RDS) gene have been reported in autosomal dominant retinitis pigmentosa and variable forms of pattern dystrophy of the retinal pigment epithelium. We screened the rhodopsin and the peripherin/RDS gene in the members of two families who presented the clinical features of pattern dystrophy of the retinal pigment epithelium transmitted as an autosomal dominant trait. No migration patterns were detected in single strand conformation polymorphism or hydrolink gels. Both the rhodopsin and the peripherin/RDS gene were normal in one family. In the second, the proband had a normal rhodopsin gene and, although he passed a different haplotype to each of his affected daughters, there was no linkage with the peripherin/RDS gene. The origin of the retinal disturbance in our two pedigrees must therefore be sought, if indeed DNA is involved, elsewhere in the genome. Our findings provide additional evidence that pattern dystrophies of the retinal pigment epithelium may be pathogenically related in spite of different etiological origins. The genetic polymorphism can probably account for the wide range of phenotypes.

Eye Proteins↗

PubMed1997

Patterns of geographic mobility of persons with AIDS in Canada from time of AIDS index diagnosis to death.

OBJECTIVE: To characterize migration patterns of persons with AIDS in Canada during the period from AIDS diagnosis to death. DESIGN: Descriptive, population-based study. SETTING: Canada. PATIENTS: Canada's AIDS Case Reporting Surveillance System (ACRSS) was linked to deaths in the Canadian Mortality Data Base (CMDB). Probabilistic linkage was based on initials, date of birth, date of death, birthplace, and location at diagnosis and at death. Analysis was restricted to AIDS cases reported from Jan. 1, 1982, to Sept. 30, 1994, and to deaths reported from Jan. 1, 1982, to Dec. 31, 1992. MAIN OUTCOME MEASURES: Change in usual place of residence; migration rates by region and community size. RESULTS: A total of 5755 AIDS cases recorded in the ACRSS were linked to deaths in the CMDB. Of these linked cases, 5366 (93%) included information on province or territory of usual residence or community size. A total of 160 (3.0%) persons with AIDS changed their province or territory of residence between the time of their AIDS diagnosis and death. Multivariate analysis indicated that those who changed residences between AIDS index diagnosis and death were more likely than other persons with AIDS to live in provinces other than British Columbia, Ontario and Quebec (p < 0.001), to be diagnosed earlier (p = 0.004), to be younger (p < 0.001) and to be gay or bisexual (p = 0.042). CONCLUSIONS: Our analysis revealed that only a small proportion of persons changed their residence between AIDS diagnosis and death. Geographic mobility was the greatest among persons with AIDS residing outside of the regions where the overwhelming majority of persons with AIDS in this country reside.

Acquired Immunodeficiency Syndrome↗

PubMed1990

Timing and patterns of astrocyte migration from xenogeneic transplants of the cortex and corpus callosum.

The timing, pattern, and pathway of astrocyte migration were investigated in vivo by transplantation of CD-1 mouse cerebral cortex (E13-14) or corpus callosum (P2-3) into neonatal rat cortex. A monoclonal antibody specific for a mouse astrocyte surface antigen (M2) was used to identify the location of the grafts and the migrated donor astrocytes. Within the host cortex, astrocytes from cortical grafts began migration at post-transplantation day (PTD) 7. Over the next 4 days, the most distant displaced donor cells were found progressively further away from the grafts, migrating at a rate of about 220 microns/day. After PTD 11, the migration rate for the farthest displaced donor cells slowed to 25 microns/day, and the cells appeared to stop at about PTD 16 at a distance of 1,100 microns from the edge of the graft. Astrocytes had a faster migration speed in the white matter and covered a longer distance (5 mm) than those in the gray matter, extending on occasion into the contralateral hemisphere. The patterns of astrocyte migration differed depending on local cues around the transplant. Donor astrocytes that had been implanted into the host cortex migrated toward the host cortical surface, sometimes in several radial lines. Astrocytes from grafts, especially callosal grafts, placed in the subcortical white matter migrated along the host fiber tracts. Many astrocytes transplanted into the hippocampus formed laminar patterns close to the hippocampal neuronal layers. These results suggest that the direction, pattern, and speed of astrocyte migration are influenced by local substrates in the host brain.

Animals↗

PubMed1990

Elderly Hispanic migration in the United States.

The specific aim of this study was to extend the analysis of migration patterns to Hispanics (Mexican, Cuban, Puerto Rican, and Other Hispanic) over the age of 60. The 1980 Census public use sample provided the data for this study, which was structured by four research expectations derived from features of the Hispanic population and from migration concepts. First, because of population growth, migration from abroad was expected to be heavy, and about half came from abroad. Second, because of the pattern of Hispanic population concentration and the different settlement patterns of the four subgroups, a relatively small migration system with distinct subsystems for the four nationality groups was expected and found. Florida is the major ethnomagnet. Third, traditional family values, as reflected in dependent living arrangements, were expected to be more prevalent among migrants from abroad, and they were. Finally, returning to one's state of birth was highest among Mexican interstate migrants, as expected.

Aged↗

PubMed1991

Patterns of epithelial migration in the unaffected ear in patients with a history of unilateral cholesteatoma.

Epithelial migration in a centrifugal manner is an established phenomenon in the normal human tympanic membrane. This pattern of migration is symmetrical in both ears of any one individual. We present a prospective study on the pattern of tympanic ink dot migration on the normal drum, in patients with a history of cholesteatoma in one ear. It was demonstrated that patients who develop cholesteatoma have a normal migratory pattern and rate in the unaffected ear. The conclusion from this study is that defective migration is not the initiating factor in the development of acquired cholesteatoma.

Cell Movement↗

PubMed1980

Leukocyte migration enhancement as an indicator of immunologic enhancement. II. Malignancy.

Leukocyte migration studies were performed on 19 cancer patients and 24 control subjects. Amniotic fluid (AF) as well as autologous plasma (PL) were investigated. No difference in the migration pattern between patients and control subjects was observed with AF, but cancer patients showed significant leukocyte migration enhancement (LME) with PL when compared to control subjects (p less than 0.04). Among 18 cancer patients with persistent disease only three did not show significant LME. All three represented specifically immunodepressed states. None of the untreated group of cancer patients failed to show LME with autologous PL. It is concluded that, as in pregnancy, an immunologic active factor is present in PL of cancer patients which induces a specific subpopulation of leukocytes and thereby LME. The possible mechanism of activation is briefly discussed. Through the detection of LME leukocyte migration may become of importance for the early detection of malignancy and monitoring of treatment success.

Adenocarcinoma↗

PubMed1985

Homozygosity, effective number of alleles, and interdeme differentiation in subdivided populations.

The amount and pattern of genetic variability in a geographically structured population at equilibrium under the joint action of migration, mutation, and random genetic drift is studied. The monoecious, diploid population is subdivided into panmictic colonies that exchange migrants. Self-fertilization does not occur; generations are discrete and nonoverlapping; the analysis is restricted to a single locus in the absence of selection; every allele mutates to new alleles at the same rate. It is shown that if the number of demes is finite and migration does not alter the deme sizes, then population subdivision produces interdeme differentiation and the mean homozygosity and the effective number of alleles exceed their panmictic values. A simple relation between the mean probability of identity and the mean homozygosity is established. The results apply to a dioecious population if the migration pattern and mutation rate are sex independent.

Alleles↗

PubMed1983

Proliferation and migration of rat incisor mesenchymal cells.

Sixty female Wistar rats were injected with tritiated thymidine and killed at intervals between 1 hr and 72 hr after injection. Autoradiographs of paraffin and Vestopal W embedded sagittal sections of the maxillary incisors were prepared. The distribution of labeled cells after 1 hr revealed the basal pulp cells and the preodontoblasts as proliferative cells. The growth rate of the incisor and the migration of the basal pulp cells were established from the position of labeled cells at 72 hr observation time. The number and localization of labeled and unlabeled mitoses were registered in order to determine the duration of the generation cycle of the proliferative cells. The identical cell generation time of preodontoblasts and basal pulp cells and the migration pattern of the latter indicate that the preodontoblasts are renewed by preodontoblast multiplication and not by migration of basal pulp cells.

Animals↗

PubMed1996

Contribution of early-emigrating midbrain crest cells to the dental mesenchyme of mandibular molar teeth in rat embryos.

Teeth are formed by reciprocal interactions between the epithelium and mesenchyme in the first pharyngeal arch. Although the contribution of midbrain and hindbrain crest cells to the first pharyngeal arch has been previously examined in rodent embryos, no direct evidence exists that these cells are actually involved in the dental mesenchyme. In order to elucidate the contribution of the cranial neural crest cells in tooth formation, we first identified the emigration sites and stages providing the crest cells that migrate to the presumed tooth-forming region of the mandibular prominence. Focal labeling with DiI was performed at the midbrain and anterior hindbrain crests in rat embryos, and the labeled embryos were cultured for 30 or 60 hr. The resultant migration patterns indicated that posterior midbrain crest cells emigrating by the end of the 4-somite stage predominantly migrated to the region where tooth buds normally develop. Second, we established a new type of long-term culture system in which whole embryo culture is followed by a mandibular organ culture. Using this system, rat embryos were maintained from the early-somite stage and the molars in the explants were able to reach the bud stage within 8 days. Finally, to ascertain if posterior midbrain crest cells emigrating by the end of the 4-somite stage were involved in the dental mesenchyme, these cells were labeled with DiI and processed for the long-term culture. Labeled crest cells were clearly detectable in the dental mesenchyme. These findings indicate that the early-emigrating posterior midbrain crest cells contribute to mandibular molar tooth development in rat embryos.

Animals↗

PubMed1990

Enzymatic heterogeneity of seminomas.

Heterogeneity of placental-like alkaline phosphatase (PLAP-like enzyme) in seminoma was studied. PLAP-like enzyme from seminoma tissues was separated into three areas with different proportions between tumors, while PLAP and PLAP-like enzymes in normal testes were separated into two areas on the basis of hydrophobicity. By use of lectin affinity chromatography, PLAP-like enzyme in seminoma revealed extra sugar chains compared to PLAP, indicating heterogeneity of the carbohydrate moiety. However, the glycosylation patterns were found to be essentially similar between seminoma and normal testis. On isoelectric focusing, differences in migration patterns of PLAP-like enzyme were revealed between seminoma and normal testis as well as between PLAP-like enzyme and PLAP. The differences in charge were mainly due to differences in sialylation of the molecules. The complex pattern on isoelectric focusing was not altered by neuraminidase treatment, indicating a considerable charge heterogeneity within the population of PLAP-like enzyme molecules from seminoma.

Alkaline Phosphatase↗

PubMed1991

Characterization of seminoma-derived placental-like alkaline phosphatase.

Characteristics of placental-like alkaline phosphatase (PLAP-like enzyme) in seminoma was studied. By use of lectin affinity chromatography, PLAP-like enzyme in seminoma revealed extra sugar chains compared to placental alkaline phosphatase (PLAP), indicating heterogeneity of the carbohydrate moiety. However, the glycosylation patterns were found to be essentially similar between seminoma and normal testis. On isoelectric focusing, differences in migration patterns were revealed between seminoma-derived and normal testis-derived PLAP-like enzyme as well as between PLAP-like enzyme and PLAP. The differences in charge were mainly due to differences in sialylation of the molecules. The complex pattern of PLAP-like enzyme from seminoma on isoelectric focusing was not altered by neuraminidase treatment, indicating a considerable charge heterogeneity within the population of the enzyme molecules from the tumor.

Alkaline Phosphatase↗

PubMed1997

A novel mutation in the sterol 27-hydroxylase gene of a Pakistani family with autosomal recessive cerebrotendinous xanthomatosis.

Cerebrotendinous xanthomatosis (CTX) is a rare autosomal recessive disorder of lipid storage with prominent neurologic features. The disease is associated with mutations in CYP27, which encodes mitochondrial sterol 27-hydroxylase, an enzyme that catalyzes the oxidation of sterol intermediates during bile acid synthesis. The loss of this enzyme results in accumulation of cholestanol in the nervous system and other tissues. Six different mutations have been previously described in CTX. We analyzed a Pakistani family, which included four affected individuals with clinical characteristics of CTX, for mutations in CYP27. The exons of CYP27 in the family DNA were amplified by polymerase chain reaction (PCR) and analyzed for mutations by band shifts (single stranded conformational polymorphism [SSCP]) and DNA sequencing. The PCR product for exon 4 showed an SSCP change in this family. The DNA of affected individuals showed an abnormal mobility pattern interpreted as homozygous for the mutation. One non-affected sibling was homozygous for the normal migrating pattern, whereas the parents and another non-affected sibling were heterozygous. The sequence of exon 4 of affected individuals showed a substitution of C to T in codon 237, thus substituting arginine to a stop codon. This mutation would terminate the translation, which may result in a protein half the size of the wild type rendering it practically inactive.

Adult↗

PubMed1998

Rotavirus electropherotypes from the Kuala Lumpur Hospital: a re-examination after an interval of seven years.

The objective of this study was to ascertain the extent changes have occurred in the epidemiology of human rotavirus electropherotypes from the same location 7 to 8 years after an earlier study. Genomic RNA profiles of rotaviruses from diarrhoeic children admitted to the Kuala Lumpur Hospital from April to December 1996 were determined by polyacrylamide gel electrophoresis and silver staining. A total of 179 group A rotaviruses were detected from 870 children: 175 with legible staining of all RNA segments were classified into 14 distinct electropherotypes (10 and 4 with long and short migration patterns respectively). In addition, the results revealed: high predominance of long pattern electropherotypes (94% of the total electropherotypes); most long electropherotypes with RNA profiles which all 11 RNAs migrated separately (8 of 10 electropherotypes); all short electropherotypes had segments 2 and 3 that co-migrated; presence of a very numerically dominant electropherotype (75% of all electropherotypes); frequent co-circulation of the dominant electropherotype-present throughout the study period--with other electropherotypes present for limited periods; sequential temporal appearances by similar electropherotypes. These observations were similar to that of an earlier study conducted in 1988/89. Nevertheless, the dominant electropherotype in the present study was different and not among the electropherotypes detected in the earlier study.

Diarrhea, Infantile↗