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1.
Clin Exp Immunol ; 177(2): 439-53, 2014 Aug.
Article in English | MEDLINE | ID: mdl-24712857

ABSTRACT

Lenalidomide activates the immune system, but the exact immunomodulatory mechanisms of lenalidomide in vivo are poorly defined. In an observational study we assessed the impact of lenalidomide on different populations of immune cells in multiple myeloma patients. Lenalidomide therapy was associated with increased amounts of a CD8(+) T cell subset, phenotypically staged between classical central memory T cells (TCM) and effector memory T cells (TEM), consequently termed TCM/TEM. The moderate expression of perforin/granzyme and phenotypical profile of these cells identifies them as not yet terminally differentiated, which makes them promising candidates for the anti-tumour response. In addition, lenalidomide-treated patients showed higher abundance of CD14(+) myeloid cells co-expressing CD15. This population was able to inhibit both CD4(+) and CD8(+) T cell proliferation in vitro and could thus be defined as a so far undescribed novel myeloid-derived suppressor cell (MDSC) subtype. We observed a striking correlation between levels of TCM/TEM, mature regulatory T cells (T(regs)) and CD14(+) CD15(+) MDSCs. In summary, lenalidomide induces both activating and inhibitory components of the immune system, indicating the existence of potential counter-regulatory mechanisms. These findings provide new insights into the immunomodulatory action of lenalidomide.


Subject(s)
Immunologic Factors/pharmacology , Immunomodulation/drug effects , Multiple Myeloma/immunology , Thalidomide/analogs & derivatives , Aged , Female , Humans , Immunologic Factors/therapeutic use , Immunologic Memory/immunology , Immunophenotyping , Lenalidomide , Lymphocyte Activation/immunology , Male , Middle Aged , Multiple Myeloma/drug therapy , Multiple Myeloma/pathology , Myeloid Cells/drug effects , Myeloid Cells/immunology , Myeloid Cells/metabolism , Phenotype , T-Lymphocyte Subsets/drug effects , T-Lymphocyte Subsets/immunology , T-Lymphocyte Subsets/metabolism , Thalidomide/pharmacology , Thalidomide/therapeutic use
2.
J Invertebr Pathol ; 92(1): 33-8, 2006 May.
Article in English | MEDLINE | ID: mdl-16563429

ABSTRACT

Maternally inherited, cellular endosymbionts can enhance their fitness by biasing host sex ratio in favor of females. Male killing (MK), an extreme form of sex-ratio manipulation, is selectively advantageous, if the death of males results in increased microbe transmission through female siblings. In live-bearing hosts, females typically produce more embryos than are brought to term, and reproductive compensation through maternal resource reallocation from dead male embryos to female siblings provides a direct, physiological mechanism that could increase the number of daughters born to infected females, thereby promoting MK endosymbiont spread. In this study, a Wolbachia-infected line and an uninfected line of the viviparous pseudoscorpion, Cordylochernes scorpioides were genetically homogenized for nuclear DNA by repeated backcrossing of the infected line with the uninfected, laboratory population. Photomicroscopy of early-stage embryos demonstrated that female C. scorpioides invariably produced an excess of embryos, with Wolbachia-infected females producing as many early-stage embryos as uninfected female controls. However, Wolbachia-infected females that successfully carried broods to term gave birth to significantly fewer offspring, indicating that the extreme female bias characteristic of their broods results from the killing rather than the feminization of male embryos. Infected females that carried broods to term gave birth to significantly larger nymphs and did produce 10% more female offspring than uninfected females. However, the slight transmission advantage that the MK Wolbachia accrued from this reproductive compensation appears to be heavily outweighed by the high rate of spontaneous brood abortion suffered by infected females.


Subject(s)
Arthropods/parasitology , Sex Ratio , Wolbachia/physiology , Animals , Female , Host-Parasite Interactions , Male
3.
Heredity (Edinb) ; 95(1): 41-9, 2005 Jul.
Article in English | MEDLINE | ID: mdl-15931253

ABSTRACT

Bacterial endosymbionts that manipulate host reproduction are now known to be widespread in insects and other arthropods. Since they inhabit the cytoplasm and are maternally inherited, these microorganisms can enhance their fitness by biasing host sex ratio in favour of females. At its most extreme, sex ratio manipulation may be achieved by killing male embryos, as occurs in a number of insect species. Here, we provide evidence for the first case of male killing by a tetracycline-sensitive microbe in pseudoscorpions. Using a combination of inheritance studies, antibiotic treatment and molecular assays, we show that a new strain of Wolbachia is associated with extreme female bias in the pseudoscorpion, Cordylochernes scorpioides. In a highly female-biased line, sex ratio distortion was maternally inherited, and occurred in conjunction with a high rate of spontaneous abortion and low reproductive success. Antibiotic treatment cured females of the Wolbachia infection, restored offspring sex ratio to 1:1, and significantly enhanced female reproductive success. The discovery of apparent male-killing in C. scorpioides is of interest because pseudoscorpions are viviparous. Theory predicts that male killing should be favoured, if male death enhances the fitness of infected female siblings. In a live-bearing host, reallocation of maternal resources from dead male embryos to their sisters provides a direct, physiological mechanism through which fitness compensation could favour male killing by cellular endosymbionts. Our results suggest, however, that fitness compensation and the spread of male-killing endosymbionts may be undermined by a high rate of spontaneous abortion in infected females of this viviparous arthropod.


Subject(s)
Arachnida/parasitology , Wolbachia/genetics , Wolbachia/pathogenicity , Animals , Anti-Bacterial Agents/administration & dosage , Anti-Bacterial Agents/pharmacology , Female , Inheritance Patterns , Larva , Male , Mortality , Selection, Genetic , Tetracycline/administration & dosage , Tetracycline/pharmacology
4.
Int J Paediatr Dent ; 14(5): 376-9, 2004 Sep.
Article in English | MEDLINE | ID: mdl-15331004

ABSTRACT

A case is presented in which pulp capping was performed on a right first mandibular primary molar in a 7-year-old male patient. An alkaline cement powder based on mineral trioxide aggregate (MTA) was used for pulp capping. There were no pathological findings either on a radiograph taken after one year or on clinical examination after 18 months, and the right first mandibular primary molar remained vital after capping with MTA. Further clinical investigation of MTA for direct pulp capping of primary teeth should be performed.


Subject(s)
Aluminum Compounds/therapeutic use , Calcium Compounds/therapeutic use , Dental Cements/therapeutic use , Dental Pulp Capping/methods , Molar/pathology , Oxides/therapeutic use , Silicates/therapeutic use , Tooth, Deciduous/pathology , Child , Dental Caries/therapy , Dental Pulp Exposure/therapy , Drug Combinations , Follow-Up Studies , Humans , Male , Mandible , Wound Healing
5.
Science ; 303(5660): 971-5, 2004 Feb 13.
Article in English | MEDLINE | ID: mdl-14963320

ABSTRACT

The life cycles of sexually reproducing animals and flowering plants begin with male and female gametes and their fusion to form a zygote. Selection at this earliest stage is crucial for offspring quality and raises similar evolutionary issues, yet zoology and botany use dissimilar approaches. There are striking parallels in the role of prezygotic competition for sexual selection on males, cryptic female choice, sexual conflict, and against selfish genetic elements and genetic incompatibility. In both groups, understanding the evolution of sex-specific and reproductive traits will require an appreciation of the effects of prezygotic competition on fitness.


Subject(s)
Biological Evolution , Magnoliopsida/physiology , Pollen/physiology , Reproduction , Sexual Behavior, Animal , Spermatozoa/physiology , Animals , Competitive Behavior , Copulation , Female , Gene Expression , Male , Selection, Genetic , Sex Characteristics
6.
Mol Ecol ; 12(10): 2759-69, 2003 Oct.
Article in English | MEDLINE | ID: mdl-12969478

ABSTRACT

Molecular and geological evidence indicates that the emergence of the Isthmus of Panamá influenced the historical biogeography of the Neotropics in a complex, staggered manner dating back at least 9 Myr bp. To assess the influence of Isthmus formation on the biogeography of the harlequin beetle-riding pseudoscorpion, Cordylochernes scorpioides, we analysed mitochondrial COI sequence data from 71 individuals from 13 locations in Panamá and northern South America. Parsimony and likelihood-based phylogenies identified deep divergence between South American and Panamanian clades. In contrast to low haplotype diversity in South America, the Panamanian Cordylochernes clade is comprised of three highly divergent lineages: one clade consisting predominantly of individuals from central Panamá (PAN A), and two sister clades (PAN B1 and PAN B2) of western Panamanian pseudoscorpions. Breeding experiments demonstrated a strictly maternal mode of inheritance, indicating that our analyses were not confounded by nuclear-mitochondrial pseudogenes. Haplotype diversity is striking in western Atlantic Panamá, where all three Panamanian clades can occur in a single host tree. This sympatry points to the existence of a cryptic species hybrid zone in western Panamá, a conclusion supported by interclade crosses and coalescence-based migration rates. Molecular clock estimates yield a divergence time of approximately 3 Myr between the central and western Panamanian clades. Taken together, these results are consistent with a recent model in which a transitory proto-Isthmus enabled an early wave of colonization out of South America at the close of the Miocene, followed by sea level rise, inundation of the terrestrial corridor and then a second wave of colonization that occurred when the Isthmus was completed approximately 3 Myr bp.


Subject(s)
Arachnida/genetics , Coleoptera/physiology , Evolution, Molecular , Geography , Phylogeny , Animal Migration , Animals , Arachnida/physiology , Base Sequence , DNA Primers , DNA, Mitochondrial/genetics , Genetics, Population , Haplotypes/genetics , Likelihood Functions , Models, Genetic , Molecular Sequence Data , Panama , Sequence Analysis, DNA , Symbiosis
7.
Bioessays ; 22(10): 938-46, 2000 Oct.
Article in English | MEDLINE | ID: mdl-10984720

ABSTRACT

In birds and frogs, species pairs retain the capacity to produce viable hybrids for tens of millions of years, an order of magnitude longer than mammals. What accounts for these differences in relative rates of pre- and postzygotic isolation? We propose that reproductive mode is a critically important but previously overlooked factor in the speciation process. Viviparity creates a post-fertilization arena for genomic conflicts absent in egg-laying species. With viviparity, conflict can arise between: mothers and embryos; sibling embryos in the womb, and maternal and paternal genomes within individual embryos. Such intra- and intergenomic conflicts result in perpetual antagonistic coevolution, thereby accelerating interpopulation postzygotic isolation. In addition, by generating intrapopulation genetic incompatibility, viviparity-driven conflict favors polyandry and limits the potential for precopulatory divergence. Mammalian diversification is characterized by rapid evolution of incompatible feto-maternal interactions, asymmetrical postzygotic isolation, disproportionate effects of genomically-imprinted genes, and "F(2) hybrid enhancement. " The viviparity-driven conflict hypothesis provides a parsimonious explanation for these patterns in mammalian evolution.


Subject(s)
Biological Evolution , Models, Biological , Reproduction , Animals
8.
N Engl J Med ; 342(15): 1085-92, 2000 04 13.
Article in English | MEDLINE | ID: mdl-10766581

ABSTRACT

BACKGROUND: Several agents are effective in preventing Mycobacterium avium complex disease in patients with advanced human immunodeficiency virus (HIV) infection. However, there is uncertainty about whether prophylaxis should be continued in patients whose CD4+ cell counts have increased substantially with antiviral therapy. METHODS: We conducted a multicenter, double-blind, randomized trial of treatment with azithromycin (1200 mg weekly) as compared with placebo in HIV-infected patients whose CD4+ cell counts had increased from less than 50 to more than 100 per cubic millimeter in response to antiretroviral therapy. The primary end point was M. avium complex disease or bacterial pneumonia. RESULTS: A total of 520 patients entered the study; the median CD4+ cell count at entry was 230 per cubic millimeter. In 48 percent of the patients, the HIV RNA value was below the level of quantification. The median prior nadir CD4+ cell count was 23 per cubic millimeter, and 65 percent of the patients had had an acquired immunodeficiency syndrome-defining illness. During follow-up over a median period of 12 months, there were no episodes of confirmed M. avium complex disease in either group (95 percent confidence interval for the rate of disease in each group, 0 to 1.5 episodes per 100 person-years). Three patients in the azithromycin group (1.2 percent) and five in the placebo group (1.9 percent) had bacterial pneumonia (relative risk in the azithromycin group, 0.60; 95 percent confidence interval, 0.14 to 2.50; P=0.48). Neither the rate of progression of HIV disease nor the mortality rate differed significantly between the two groups. Adverse effects led to discontinuation of the study drug in 19 patients assigned to receive azithromycin (7.4 percent) and in 3 assigned to receive placebo (1.1 percent; relative risk, 6.6; P=0.002). CONCLUSIONS: Azithromycin prophylaxis can safely be withheld in HIV-infected patients whose CD4+ cell counts have increased to more than 100 cells per cubic millimeter in response to antiretroviral therapy.


Subject(s)
AIDS-Related Opportunistic Infections/prevention & control , Anti-Bacterial Agents/therapeutic use , Antibiotic Prophylaxis , Azithromycin/therapeutic use , HIV Infections/drug therapy , Mycobacterium avium-intracellulare Infection/prevention & control , Adult , Anti-Bacterial Agents/adverse effects , Antibiotic Prophylaxis/adverse effects , Azithromycin/adverse effects , CD4 Lymphocyte Count , Disease Progression , Double-Blind Method , Female , Follow-Up Studies , HIV/genetics , HIV Infections/immunology , HIV Infections/mortality , Humans , Male , RNA, Viral/blood
9.
Proc Natl Acad Sci U S A ; 96(18): 10236-41, 1999 Aug 31.
Article in English | MEDLINE | ID: mdl-10468592

ABSTRACT

Although it is generally accepted that females can gain material benefits by mating with more than one male, the proposal that polyandry provides genetic benefits remains controversial, largely because direct experimental support is lacking. Here, we report the results of a study testing for genetic benefits to polyandry in the pseudoscorpion Cordylochernes scorpioides. In an experiment that controlled for male mating experience and the number of spermatophores accepted by a female, twice-mated females received either one sperm-packet from each of two different males (the "DM" treatment) or two sperm-packets from a single male (the same male or "SM" treatment). Over their lifetime, DM females gave birth to 32% more offspring than did SM females, primarily because of a significantly reduced rate of spontaneous abortion. This result could not be attributed to male infertility nor to lack of sexual receptivity in males paired with previous mates. Spermatophore and sperm numbers did not differ between males presented with a previous mate and males paired with a new female. Because SM and DM females received the same quantity of ejaculate, it was possible to eliminate material benefits as a contributor to the enhanced reproductive success of DM females. The reduction in embryo failure rate achieved by DM females is most consistent with the genetic incompatibility avoidance hypothesis, i.e., that polyandry enables females to exploit postcopulatory mechanisms for reducing the risk and/or cost of fertilization by genetically incompatible sperm. This study, which rigorously controlled for material benefits and excluded inbreeding effects, demonstrates that polyandry provides genetic benefits that significantly enhance female lifetime reproductive success.


Subject(s)
Biological Evolution , Reproduction/genetics , Scorpions/genetics , Scorpions/physiology , Sexual Behavior, Animal , Animals , Female , Male , Sperm Count , Spermatogonia/physiology , Spermatozoa/physiology
10.
Proc Natl Acad Sci U S A ; 95(23): 13732-6, 1998 Nov 10.
Article in English | MEDLINE | ID: mdl-9811869

ABSTRACT

In most animal species, particularly those in which females engage in polyandry, mate choice is a sequential process in which a female must choose to mate or not to mate with each male encountered. Although a number of theoretical and empirical investigations have examined the effects of sequential mate choice on the operation of sexual selection, how females respond to solicitation by previous mates has received little attention. Here, we report the results of a study carried out on the polyandrous pseudoscorpion, Cordylochernes scorpioides, that assessed the sexual receptivity of once-mated females presented after a lapse of 1.5 hr or 48 hr with either their first mate or a different male. Females exhibited a high level of receptivity to new males, irrespective of intermating interval. By contrast, time between matings exerted a strong effect on female receptivity to previous mates. After a lapse of 48 hr, females did not differ significantly in their receptivity toward previous mates and different males, whereas at 1.5 hr after first mating, females were almost invariably unreceptive to males from whom they had previously accepted sperm. This result could not be attributed to male size or mating experience or to male sexual receptivity. Indeed, males were as willing to transfer sperm to a previous mate as they were to a new female. This difference between males and females in their propensity to remate with the same individual may reflect a conflict between the sexes, with males seeking to minimize postcopulatory sexual selection and females actively keeping open the opportunity for sperm competition and female choice of sperm by discriminating against previous mates.


Subject(s)
Scorpions/physiology , Sexual Behavior, Animal , Animals , Female , Male , Spermatozoa
11.
Mol Phylogenet Evol ; 7(2): 208-16, 1997 Apr.
Article in English | MEDLINE | ID: mdl-9126563

ABSTRACT

The neotropical pseudoscorpion Cordylochernes scorpioides (Chernetidae: Lamprochernetinae) is currently described as a single species ranging from Central America to northern Argentina. However, interpopulation crosses have recently demonstrated that C. scorpioides actually represents a complex of cryptic species. Here we present mitochondrial COI gene sequence data from C. scorpioides individuals from Panama, Trinidad, and French Guiana which demonstrate little or no intrapopulation variability but divergence ranging from 2.6 to 13.8% between geographic populations. Phylogenetic analysis provides evidence of a major split between C. scorpioides lineages from Central and South America. Levels of interpopulation mtDNA divergence correspond well with previously established patterns of postzygotic reproductive incompatibility between geographically distinct units within the C. scorpioides complex. By contrast, multivariate morphometric analysis demonstrates that extensive sequence divergence has occurred in the absence of appreciable morphological differentiation between the populations. To provide a framework for assessing the scale of geographic divergence in C. scorpioides, Cordylochernes sequences were compared with homologous sequence from its presumed sister taxon, Lustrochernes, and from Parachernes and Semeiochernes, representatives of the second chernetid subfamily, the Chernetinae. Our preliminary, generic-level analysis suggests that COI sequence data may prove useful in resolving relationships within this problematic family.


Subject(s)
Arachnida/genetics , DNA, Mitochondrial/genetics , Animals , Arachnida/classification , Base Sequence , Central America , DNA Primers/genetics , Evolution, Molecular , Female , Genetic Variation , Genetics, Population , Male , Molecular Sequence Data , Phylogeny , South America , Species Specificity , Tropical Climate
12.
Mol Ecol ; 3(5): 517-22, 1994 Oct.
Article in English | MEDLINE | ID: mdl-7952332

ABSTRACT

We describe the first application of the charomid-cloning method for developing single-locus minisatellite DNA probes in a terrestrial arthropod. From a genomic library of the neotropical pseudoscorpion, Cordylochernes scorpioides, we have isolated two probes with heterozygosities exceeding 95%. These probes yielded single-locus patterns after only low stringency washing and in the absence of genomic competitor DNA. Analysis of three pedigrees indicated germline stability and showed no evidence of linkage between the loci. Patterns of allelic transmission generally conformed closely to Mendelian expectations but large offspring numbers did enable detection of one example of significant bias in allele inheritance. Two test cases are presented to illustrate the clarity and power with which these probes can establish paternity: (i) a female mated to three unrelated males, and (ii) a female mated to two of her brothers. In both cases, a single probe could be used to assign the paternity of all offspring.


Subject(s)
Arachnida/genetics , DNA Probes , DNA, Satellite/genetics , Animals , Cloning, Molecular , Coleoptera , Fathers , Female , French Guiana , Genetic Carrier Screening , Genetic Vectors , Genomic Library , Male , Sexual Behavior, Animal
13.
J Burn Care Rehabil ; 9(6): 648-9, 1988.
Article in English | MEDLINE | ID: mdl-3220872

ABSTRACT

A fire prevention/burn education program has been developed, presented, and evaluated. The program was presented to teenage students in four inner city high schools who were also the parents of infants and toddlers. The program was judged to be effective based on testing results, classroom teacher response, and school administration endorsement.


Subject(s)
Burns/prevention & control , Fires/prevention & control , Mothers , Schools , Adolescent , Female , Health Education , Humans
14.
J Med Chem ; 21(7): 613-23, 1978 Jul.
Article in English | MEDLINE | ID: mdl-671460

ABSTRACT

A series of 62 diarylamidine derivatives was evaluated for their antiproteolytic activity. In all but two of the compounds one or both of the amidino-substituted aryl moieties was either an indole or an indole-like ring. The latter included indene, benzimidazole, benzofuran, benzol[beta]thiophene, and several other related nitrogen-containing heterocycles. Several of the compounds exhibited considerable inhibitory potency against thrombin, trypsin, and pancreatic kallikrein. An outstanding inhibitor of trypsin was found in bis(5-amidino-2-benzimidazolyl)methane (compound 42) with a Ki value of 1.7 X 10(-8) M(pH. 8.1, 37 degrees C). Another derivative, 1,2-di(4-amidino-2-benzofuranyl)ethane (compound 21), proved to be a highly effective inhibitor of the overall blood clotting process. From a general structure-activity standpoint these compounds demonstrate that minor structural variations of low-molecular-weight inhibitors can result in significant changes in specificity and potency with regard to antiproteolytic activity.


Subject(s)
Amidines/chemical synthesis , Indoles/chemical synthesis , Protease Inhibitors , Amidines/pharmacology , Anticoagulants/chemical synthesis , Benzimidazoles/chemical synthesis , Benzimidazoles/pharmacology , Benzofurans/chemical synthesis , Benzofurans/pharmacology , Blood Coagulation Tests , Humans , Indoles/pharmacology , Kallikreins/antagonists & inhibitors , Structure-Activity Relationship , Thiophenes/chemical synthesis , Thiophenes/pharmacology , Thrombin/antagonists & inhibitors , Thromboplastin , Time Factors , Trypsin Inhibitors/chemical synthesis
15.
Anesth Analg ; 57(1): 13-7, 1978.
Article in English | MEDLINE | ID: mdl-147039

ABSTRACT

A new stimulator is described with characteristics designed to take advantage of recent knowledge of the pharmacology of neuromuscular relaxants and events involved in normal neuromuscular transmission. The stimulator has proven as useful in performance of peripheral nerve blocks as in monitoring neuromuscular blockade.


Subject(s)
Electric Stimulation/instrumentation , Monitoring, Physiologic/instrumentation , Nerve Block , Humans , Neuromuscular Junction/physiology , Neuromuscular Nondepolarizing Agents/pharmacology , Peripheral Nerves
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