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Human immunodeficiency virus type 1 infection of cells and tissues from the upper and lower human female reproductive tract.

Viable tissue sections and isolated cell cultures from the human fallopian tube, uterus, cervix, and vaginal mucosa were examined for susceptibility to infection with human immunodeficiency virus type 1 (HIV-1). We examined infectivity by using the monocytotropic strain HIV-1(JR-FL) and several primary isolates of HIV-1 obtained from infected neonates. HIV-1 infection was measured by p24 production in short-term culture and by immunofluorescence detection of HIV-1 Nef and p24 proteins by laser scanning confocal microscopy. Three-color immunofluorescence was used to phenotype HIV-infected cells within tissue sections from each site. Our findings indicate that epithelial, stromal, and dendritic cells and cells with CD14+ CD4+, CD14-CD4-, and CD4+ CD14- phenotypes from the female reproductive tract are infectable with HIV-1. Of importance is the finding that tissues from the upper reproductive tract are susceptible to infection with HIV-1. Moreover, tissue samples from women in all stages of the menstrual cycle, including postmenopausal women (inactive), could be infected with HIV-1. Female reproductive tract cells required a minimum of 60 min of exposure to HIV-1 in order for infection to occur, in contrast to peripheral blood lymphocytes, which became infected after being exposed to HIV-1 for only 1 min. These findings demonstrate that HIV-1 can infect cells and tissues from different sites within the female reproductive tract and suggest that multiple cell types, including epithelial cells, may be targets for the initial infection by HIV-1.

Acquired Immunodeficiency Syndrome↗

Members of the 70 kDa heat shock protein family specifically recognize sulfoglycolipids: role in gamete recognition and mycoplasma-related infertility.

We have previously shown that several mycoplasma species associated with infertility bind specifically to sulfated glycolipids isolated from the mammalian reproductive tract. We now show that a germ cell-specific sulfoglycolipid binding protein (SLIP 1), which is a potent inhibitor of sperm/egg binding in vitro, is immunologically related to the heat shock protein(Hsp) 70 family of stress proteins and that Hsps are surface antigens in male germ cells. Our present data demonstrate that several mycoplasma and mammalian Hsps share this glycolipid binding specificity in vitro, and suggest that surface Hsps can function as adhesins which mediate sulfoglycolipid recognition in infectious disease and normal reproductive physiology.

Animals↗

The novel antibacterial peptide ceratotoxin A alters permeability of the inner and outer membrane of Escherichia coli K-12.

Ceratotoxins are antibacterial 3-kDa amphiphilic peptides isolated from the female reproductive apparatus of the medfly Ceratitis capitata. The antibacterial activity of a chemically synthesized ceratotoxin A (ctx A) has been investigated. Ctx A was mainly active against Gram-negative organisms, and it had a lytic effect on nongrowing Escherichia coli K-12. Data showed that ctx A alters both the outer and the inner membrane of E.coli K-12 cells.

Animals↗

Constitutive expression of the SAP1 gene from willow (Salix discolor) causes early flowering in Arabidopsis thaliana.

SAP1-1 and SAP1-2 were isolated from the male reproductive buds of willow (Salix discolor, clone S365). SAP1-1 differs from SAP1-2 based on a few nucleotide substitutions, but the sizes of their full-length cDNAs are identical. The deduced amino acid sequences of SAP1-1 and SAP1-2 were 98% similar and contain the same C-terminal amino acid motif "GYGA" like that of PTAP1-2 from Populus trichocarpa. The expression patterns of SAP1 in various parts of the male reproductive buds of S. discolor implicate this gene in the formation of the inflorescence meristems, bracts, and floral meristems. To characterize the functions of SAP1, we assessed Arabidopsis thaliana transformed with 35S: :SAP1-1. A total of 52 transgenic T1 lines were obtained, and a 3:1 segregation ratio was obtained in the T2 generation of each line. In the T3 generation, five homozygous transgenic lines were obtained, which were used for further analysis. Screening of transgenic lines was greatly facilitated by the detection of GFP expression starting with germinating seeds. Phenotypes of the homozygous transgenic lines included early flowering, conversion of inflorescence branches to solitary flowers, formation of terminal flowers, and formation of flowers with greater number of petals, stamens, and pistils. Northern analysis showed similar expression levels in all five lines. This study provides the first functional analysis of an APETALA1 (AP1)/SQUAMOSA (SQUA) homolog from a dioecious species and suggests that SAP1 is a homolog of the AP1/SQUA gene.

Amino Acid Sequence↗

Mating-type distribution and fertility status in Magnaporthe grisea populations from Argentina.

Isolates of Magnaporthe grisea causing gray leaf spot on rice were collected in Argentina and analyzed for mating distribution and fertility. One hundred and twenty-five isolates of M. grisea were collected from rice plants between 2000 and 2003. Each isolate was tested for mating type through a polymerase chain reaction based assay. All M. grisea isolates from Argentina belonged to a single mating type, MAT1.1. The fertility status of isolates was determined using controlled crosses in vitro, pairing each isolate with GUY11 and KA9 (MAT1.2 standard hermaphroditic testers). Production of perithecia was scarce among isolates of the blast pathogen since a low percentage of them (7.2%) developed perithecia with only one of the fertile tester (KA9); all crosses failed with the other tester strain. Asci and ascospores were not observed. The presence of only one mating type and the absence of female fertile isolates indicate that sexual reproduction is rare or absent in M. grisea populations associated with rice in Argentina.

Argentina↗

Colletotrichum acutatum is the main cause of Colletotrichum leaf disease of rubber in Sri Lanka.

Colletotrichum gloeosporoides has been described as the causal agent of Colletotrichum leaf disease of rubber in Sri Lanka and other parts of the world since 1905. A study carried out on vegetative and reproductive characteristics of 52 isolates from Colletotrichum leaf disease lesions on Hevea brasiliensis in Sri Lanka revealed that only 18 isolates belong to Colletotrichum gloeosporioides. The remaining 34 isolates represented C. aculatum indicating that C. acutatum is the main cause of Colletotrichum leaf disease in Sri Lanka.

Journal Article↗

Reduced fecundity in small populations of the rare plant Gentianopsis ciliate (Gentianaceae).

Habitat destruction is the main cause for the biodiversity crisis. Surviving populations are often fragmented, i.e., small and isolated from each other. Reproduction of plants in small populations is often reduced, and this has been attributed to inbreeding depression, reduced attractiveness for pollinators, and reduced habitat quality in small populations. Here we present data on the effects of fragmentation on the rare, self-compatible perennial herb Gentianopsis ciliata (Gentianaceae), a species with very small and presumably well-dispersed seeds. We studied the relationship between population size, plant size, and the number of flowers produced in 63 populations from 1996-1998. In one of the years, leaf and flower size and the number of seeds produced per fruit was studied in a subset of 25 populations. Plant size, flower size, and the number of seeds per fruit and per plant increased with population size, whereas leaf length and the number of flowers per plant did not. The effects of population size on reproduction and on flower size remained significant if the effects were adjusted for differences in plant size, indicating that they could not be explained by differences in habitat quality. The strongly reduced reproduction in small populations may be due to pollination limitation, while the reduced flower size could indicate genetic effects.

Biodiversity↗

cDNA sequence and expression of the ceratotoxin gene encoding an antibacterial sex-specific peptide from the medfly Ceratitis capitata (diptera).

Ceratotoxins are antibacterial 3-kDa molecular mass amphiphilic peptides isolated from the female reproductive accessory glands of the medfly Ceratitis capitata. They are physiologically related to bee melittin and show amino acid sequence homology with magainin peptides. In this paper, we report the complete sequence of cDNA coding for ceratotoxin A and the expression of the gene during the life cycle of the insect. Experimental data show that the ceratotoxin is a gene expressed exclusively in the imaginal stages and that it is female-specific, related to sexual maturity, and stimulated by mating. Differently from most antibacterial insect hemolymph peptides, it is not induced by microbial infection. Western blot analysis using an anti-ceratotoxin antibody indicates the female accessory glands as the only site where the production of the ceratotoxin peptide occurs.

Amino Acid Sequence↗

Inbreeding, marital movement, and genetic isolation of a rural Appalachian population.

Genealogical, marital, birthplace and age-at-marriage data were collected on a random sample of 275 reproducing couples from the population of a rural Appalachian county in north-eastern Tennessee. Genealogies covering the three extant generations provided the data for a surname isonymy analysis to determine the amount of inbreeding prevalent, while the marital, birthplace and age at marriage data were used to ascertain the components of marital movement, i.e., marital distance, orientation of marital movement, spatial exogamy, and "diffusion". The effective breeding population and effective immigration rate were calculated for the county population and these in turn were used to compute the coefficient of breeding isolation for the currently reproduction population. Our conclusions agree with those of an earlier genetic and demographic study on one segment of the same population. The more extensive demographic analysis illustrates the value of such studies as this for providing background for interpretations of genetic variation.

Consanguinity↗

Human seminal plasma inhibits brain nitric oxide synthase activity.

Nitric oxide is a chemical messenger which functions as a neurotransmitter or as a cytotoxic agent. Nitric oxide synthase (NOS) has been isolated from various mammalian reproductive tissues. The presence or absence of NOS in spermatozoa has not yet been reported. We therefore tested human and murine spermatozoa for NOS activity by measuring the conversion of arginine to citrulline. No activity was found either in human or in murine spermatozoa. Human native semen and human seminal plasma exerted an inhibition on brain NOS activity, as assayed on rat brain cytosolic fractions. This inhibitory effect was dependent on the amount of protein present in the human seminal plasma. No inhibitory effect was observed when homogenates of washed spermatozoa were tested. The human seminal plasma did not affect the Michaelis constant (Km) of NOS for L-arginine (endogenous NOS substrate) whereas the maximal velocity (Vmax) was reduced, suggesting that it contains a non-competitive inhibitor of brain NOS. This inhibitory component was virtually insensitive to heat; a 10 min treatment to 95 degrees C only slightly reduced its ability to inhibit brain NOS. The physiological relevance of our observations remains to be elucidated. Human seminal plasma may exert an inhibition of nitric oxide synthesis on cells other than spermatozoa or on cells from the male or female genital tract, modulating directly or indirectly (via modulation of reactive oxygen species formation) the functional state of the spermatozoa.

Animals↗

Expression of epidermal growth factor (EGF) and the EGF receptor in the porcine oviduct.

The production, secretion, and localization of epidermal growth factor (EGF) and the distribution of the EGF receptor (EGF-R) were examined in the isthmus (I) and ampulla (A) of the oviducts from cyclic (C) and early-pregnant (P) gilts. Sexually mature gilts (n = 20) were divided equally into two groups: C and P. P gilts were bred twice (at 0 and 24 h), and all gilts were killed 48 h after onset of estrus. After removal of reproductive tracts, oviducts were isolated, flushed, opened longitudinally, divided by anatomical region, cut into 1-3-mm3 pieces, and placed in Dulbecco's modified Eagle's Essential medium (DMEM: F-12 + ITS [insulin, 5 micrograms/ml; transferrin, 5 micrograms/ml; and selenious acid, 5 ng/ml] + antibiotic). Half the tissue and medium were immediately homogenized and centrifuged, and the supernatant was removed. The remaining tissue was cultured in the medium for 24 h at 37 degrees C and 5% CO2, then prepared similarly for analysis. EGF was measured in the supernatant by a heterologous RIA. Concentration of EGF was expressed as nanogram/milliliter of EGF per milligram of protein in wet tissue. EGF concentrations were present in both regions of the oviducts of C and P gilts. It was greater in I than in A tissues for both C (I = 16.21 ng/ml vs. A = 13.91 ng/ml; p < 0.05) and P gilts (I = 14.27 ng/ml vs. A = 12.53 ng/ml; p < 0.10). Higher concentrations of EGF were found in I tissue of C gilts than in P gilts (C = 16.21 ng/ml vs. P = 14.27 ng/ml; p < 0.05). The media assayed from cultured explants of I and A sections from C and P gilts gave results that were highly correlated with those of immediately prepared tissue sections. Localization of EGF in frozen oviductal tissue sections was demonstrated by immunohistochemistry. The primary site of EGF immunostaining occurred in the epithelial cells (with highest intensity at the apical border) of both C and P gilts. A and I tissue sections from C gilts showed localization of EGF immunostaining mainly in epithelial cells and lamina propria cells, while those from P gilts stained less intensely. The presence of EGF-R was shown by incubating tissue imprints and frozen sections with EGF-erythrosin isothiocyanate, which revealed that EGF-R were distributed mainly on the membranes of epithelial cells. The study indicates that EGF and EGF-R are present in oviductal epithelial cells in both C and P gilts, with the highest concentration of EGF in C gilts.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

A set of MHC haplotypes found among Finnish couples suffering from recurrent spontaneous abortions.

PROBLEM AND METHOD: The role of major histocompatibility complex (MHC) genes in the etiology of recurrent spontaneous abortion (RSA) was studied by analyzing the polymorphism of several, at least 14, immunogenetically important MHC genes either by serological or molecular methods in 56 Finnish RSA couples, and in 29 infants born to these families during the follow-up period of two years after the abortions. RESULTS: The haplotype analysis showed that the RSA couples had significantly increased sharing of MHC fragments, compared to the control families. Furthermore, the MHC risk markers for abortions defined 12 different, extended MHC haplotypes that were found in a significantly higher proportion among persons in the RSA group (45%) than in the controls (11%). However, neither of these observations associated with the reproductive success of the study couples. CONCLUSIONS: The results suggest that extended MHC haplotypes, disadvantageous for reproduction, exist in some isolated populations, such as the Finns.

Abortion, Habitual↗

Experimental reproduction of Potomac horse fever in horses with a newly isolated Ehrlichia organism.

Potomac horse fever, a recently recognized disease of equines, characterized by high fever, leukopenia, and a profuse diarrhea, was studied for its etiology. An Ehrlichia organism was isolated in equine macrophage-fibroblast cell cultures and mouse macrophage cell cultures from the mononuclear cells of blood of infected horses. The agent was continuously propagated in mouse macrophage cell cultures. The organism multiplied in the cytoplasm of mouse macrophage cells and was identified by Giemsa staining, acridine orange staining, and by indirect immunofluorescence with convalescent sera from infected horses. The disease was experimentally reproduced in horses inoculated with Ehrlichia-infected cell culture material. The Ehrlichia organism was reisolated from the blood of these infected horses during the course of the disease. Antibody against the organism was detected in the sera of experimentally infected horses. This study confirmed that the new Ehrlichia organism is the etiological agent of Potomac horse fever.

Animals↗