Constraints on Dark Matter Properties from Observations of Milky Way Satellite Galaxies.

We perform a comprehensive study of Milky Way (MW) satellite galaxies to constrain the fundamental properties of dark matter (DM). This analysis fully incorporates inhomogeneities in the spatial distribution and detectability of MW satellites and marginalizes over uncertainties in the mapping between galaxies and DM halos, the properties of the MW system, and the disruption of subhalos by the MW disk. Our results are consistent with the cold, collisionless DM paradigm and yield the strongest cosmological constraints to date on particle models of warm, interacting, and fuzzy dark matter. At 95% confidence, we report limits on (i) the mass of thermal relic warm DM, m_{WDM}>6.5 keV (free-streaming length, λ_{fs}≲10h^{-1} kpc), (ii) the velocity-independent DM-proton scattering cross section, σ_{0}<8.8×10^{-29} cm^{2} for a 100 MeV DM particle mass [DM-proton coupling, c_{p}≲(0.3 GeV)^{-2}], and (iii) the mass of fuzzy DM, m_{ϕ}>2.9×10^{-21} eV (de Broglie wavelength, λ_{dB}≲0.5 kpc). These constraints are complementary to other observational and laboratory constraints on DM properties.

Detection of Cross-Correlation between Gravitational Lensing and γ Rays.

In recent years, many γ-ray sources have been identified, yet the unresolved component hosts valuable information on the faintest emission. In order to extract it, a cross-correlation with gravitational tracers of matter in the Universe has been shown to be a promising tool. We report here the first identification of a cross-correlation signal between γ rays and the distribution of mass in the Universe probed by weak gravitational lensing. We use data from the Dark Energy Survey Y1 weak lensing data and the Fermi Large Area Telescope 9-yr γ-ray data, obtaining a signal-to-noise ratio of 5.3. The signal is mostly localized at small angular scales and high γ-ray energies, with a hint of correlation at extended separation. Blazar emission is likely the origin of the small-scale effect. We investigate implications of the large-scale component in terms of astrophysical sources and particle dark matter emission.

Search for L5 Earth Trojans with DECam.

Most of the major planets in the Solar System support populations of co-orbiting bodies, known as Trojans, at their L4 and L5 Lagrange points. In contrast, Earth has only one known co-orbiting companion. This paper presents the results from a search for Earth Trojans using the DECam instrument on the Blanco Telescope at CTIO. This search found no additional Trojans in spite of greater coverage compared to previous surveys of the L5 point. Therefore, the main result of this work is to place the most stringent constraints to date on the population of Earth Trojans. These constraints depend on assumptions regarding the underlying population properties, especially the slope of the magnitude distribution (which in turn depends on the size and albedo distributions of the objects). For standard assumptions, we calculate upper limits to a 90% confidence limit on the L5 population of N ET < 1 for magnitude H < 15.5, N ET =60-85 for H < 19.7, and N ET = 97 for H=20.4. This latter magnitude limit corresponds to Trojans ∼300 m in size for albedo 0.15. At H=19.7, these upper limits are consistent with previous L4 Earth Trojan constraints and significantly improve L5 constraints.

The human membrane progesterone receptor gene: genomic structure and promoter analysis.

Rapid, nongenomic effects of steroids are likely to be mediated by membrane receptors not by intracellular steroid receptors. We recently identified a progesterone membrane binding protein (mPR) from human liver. The corresponding hmpr gene is comprised of 3 exons and 2 introns. The promoter sequence of hmpr lacks a typical TATA box but contains instead a high homology to a transcription Initiatior consensus sequence, which overlaps the experimentally determined transcriptional start site. The major proximal promoter is GC-rich and sequence analysis revealed a CpG island spanning the transcriptional start site. Several putative cis-regulatory DNA-motifs, which represent possible binding sites for transcription factors like AP2, NF-AT, Ahr/Arnt and C/EBP were identified in the genomic upstream region by sequence homology. Functional analysis of differently deleted fragments of the hmpr upstream region in a GFP-reportergene assay in transiently transfected cultured cells indicates the general testability of the hmpr promoter in vivo.

Nongenomic actions of steroids--from the laboratory to clinical implications.

In the classical concept of steroid action, steroids bind to cytoplasmic receptors and modulate nuclear transcription after translocation of steroid-receptor complexes into the nucleus. Due to similarities of molecular structure, receptors for steroids, retinoids, vitamin D3 and thyroid hormone are considered to represent a superfamily of receptors. While genomic steroid effects been evident for several decades, rapid effects of steroids have been characterized only recently. These rapid actions are likely to be transmitted by specific membrane receptors. Binding sites in membranes have been characterized which display binding features compatible with an involvement in rapid steroid signaling. Characteristics of putative membrane receptors are completely distinct from those of intracellular steroid receptors, a fact which is further supported by the inability of classic steroid receptor antagonists to suppress nongenomic steroid actions. The cloning and functional expression of a putative progesterone membrane receptor has been achieved. Drugs that specifically modulate nongenomic action alone or even both genomic and nongenomic actions may be applied in various areas such as the cardiovascular and central nervous systems, and treatment of infertility and electrolyte homeostasis.

CD1d structure and regulation on human thymocytes, peripheral blood T cells, B cells and monocytes.

Human T cells expressing CD161 and an invariant T-cell receptor (TCR) alpha-chain (Valpha24invt T cells) specifically recognize CD1d and appear to have immunoregulatory functions. However, the physiological target cells for this T-cell population, and whether alterations in CD1d expression contribute to the regulation of Valpha24invt T-cell responses, remain to be determined. A series of antibodies were generated to assess CD1d expression, structure and regulation on human lymphoid and myeloid cells. CD1d was expressed at high levels by human cortical thymocytes and immunoprecipitation analyses showed it to be a 48 000-MW glycosylated protein. However, after solubilization, the majority of the thymocyte CD1d protein, but not CD1d expressed by transfected cells, lost reactivity with monoclonal antibodies (mAbs) against native CD1d, indicating that it was alternatively processed. Moreover, thymocytes were not recognized by CD1d-reactive Valpha24invt T-cell clones. Medullary thymocytes and resting peripheral blood T cells were CD1d-, but low-level CD1d expression was induced on activated T cells. CD1d was expressed by B cells in peripheral blood and lymph node mantle zones, but germinal centres were CD1d-. Resting monocytes were CD1d+ but, in contrast to CD1a, b and c, their surface expression of CD1d was not up-regulated by granulocyte-macrophage colony-stimulating factor (GM-CSF) and interleukin-4 (IL-4) activation. These results demonstrate constitutive CD1d expression by human professional antigen-presenting cells and that post-translational processing of CD1d may contribute to regulation of the activity of CD1d-specific T cells.

Rapid, nongenomic steroid actions: A new age?

In the traditional theory of steroid action, steroids bind to intracellular receptors and modulate nuclear transcription after translocation of steroid-receptor complexes into the nucleus. Due to similarities of molecular structure, specific receptors for steroids, vitamin D(3) derivatives, and thyroid hormone are considered to represent a superfamily of steroid receptors. While genomic steroid effects characterized by their delayed onset of action and their sensitivity to blockers of transcription and protein synthesis have been known for several decades, rapid actions of steroids have been more widely recognized and characterized in detail only recently. Rapid effects of steroids, thyroid hormones, and the steroid hormone metabolite of vitamin D(3), 1alpha, 25-dihydroxyvitamin D(3), on cellular signaling and function may be transmitted by specific membrane receptors. Binding sites in membranes have been characterized, exposing binding features compatible with an involvement in rapid steroid signaling. Characteristics of putative membrane receptors are completely distinct from intracellular steroid receptors, a fact which is further supported by the inability of classic steroid receptor antagonists to block nongenomic steroid actions. A putative progesterone membrane receptor has been cloned and functionally expressed with regard to progesterone binding. Development of drugs that specifically affect nongenomic action alone or even both modes of action may find applications in various, areas such as in the cardiovascular and central nervous systems and treatment of preterm labor, infertility, and electrolyte abnormalities.

Rapid nongenomic effects of aldosterone in mineralocorticoid-receptor-knockout mice.

In addition to genomic effects of aldosterone, rapid nongenomic effects of steroids have been reported in various tissues that were clearly incompatible with a genomic action of aldosterone. Rapid effects of aldosterone involve second messengers such as calcium and cAMP. Specific high affinity binding sites for aldosterone have been characterized in membranes for different cells, which probably transmit those rapid steroid effects. To date, it is unclear if these binding sites are modified classical mineralocorticoid receptors (MR) or if they represent an unrelated receptor protein. The aim of the present study was to investigate whether rapid aldosterone action still occurs in the absence of the classical MR. For this purpose we used the model of MR knockout mice. Rapid effects were analyzed in skin cells, measuring intracellular calcium and cAMP levels after stimulation with aldosterone. We found that rapid effects are not only present in MR knockout mice, but that the effects are even larger than in wild-type mice cells. The results of the present study demonstrate that the classic MR is dispensable for rapid aldosterone action. The study, thus, proves that a receptor different from the classic intracellular receptor is involved in rapid aldosterone signaling.

Specific progesterone binding to a membrane protein and related nongenomic effects on Ca2+-fluxes in sperm.

Rapid, nongenomic effects of steroids are supposed to be transmitted by membrane receptors unrelated to the classic intracellular steroid receptors. In this context, a putative progesterone membrane binding protein (mPR) has been identified, recently. Here we show that expression of mPR-cDNA in CHO cells leads to increased microsomal progesterone binding. This result is mirrored by effects of an antibody raised against the recombinant E. coli mPR which suppressed the rapid progesterone-initiated Ca2+ increase in sperm. Our results support the assumption that mPR represents the first steroid membrane receptor or a part of it involved in rapid, nongenomic steroid signalling.

Cloning and tissue expression of two putative steroid membrane receptors.

We have cloned two human putative steroid binding membrane proteins, termed Hpr6.6 and Dg6. Hpr6.6 is the human homolog of a previously cloned porcine progesterone binding protein. Both proteins contain a putative transmembrane domain and a highly conserved stretch of 58 amino acids. Hpr6.6 mRNA is expressed predominantly in liver and kidney, whereas Dg6 mRNA is preferentially expressed in placenta. Hpr6.6 is located on the X chromosome and dg6 on chromosome 4. The two proteins are the first putative steroid membrane receptors cloned from man.

Biofeedback therapy for children with dysfunctional voiding.

OBJECTIVES: Biofeedback therapy has been recognized as a treatment option for children with classic dysfunctional voiding (DV) where there is inadequate pelvic floor relaxation during voiding. However, there are few articles that discuss methodology and limited sites where it is available. In the hope of making biofeedback a more practical and accessible option, we report our indications, easy to duplicate methodology, and results. METHODS: Twenty-one consecutive children diagnosed with DV refractory to standard therapy were enrolled in our biofeedback program. Therapy consisted of extensive age-appropriate explanations of DV and demonstrations of normal and abnormal voiding patterns. Cyclic uroflow studies with pelvic floor electromyography are performed, which the child monitors on analog chart and audio recorders. The child returns weekly until consistent relaxation of the pelvic floor during voiding is demonstrated. Timing between sessions is then increased to monitor progress and retention of concepts previously taught. RESULTS: An excellent clinical response was one in which there was consistent relaxation of the pelvic floor throughout voiding, normal flow pattern, and no residual urine volume (urodynamic response), coupled with profound resolution of voiding symptoms. Seventeen of 21 (81%) had an excellent response, 3 (14%) had a fair response, and 1 (5%) was too inconsistent to rate. The average number of sessions to achieve a consistent urodynamic response was 3.7 (range 2 to 14) and full clinical response somewhat longer. Average follow-up since beginning therapy has been 34 months (range 14 to 51). CONCLUSIONS: Biofeedback therapy is an effective method for treating DV with poor pelvic floor relaxation. Although initially labor intensive, it yields sustained positive results in most patients in a short time.

Localization of a putative progesterone membrane binding protein in porcine hepatocytes.

A putative membrane bound steroid receptor was localized using a peptide specific antibody. Surprisingly, the distribution of immunocytochemical staining in porcine hepatocytes cells provides evidence for the localization to endomembranes (endoplasmic reticulum, Golgi apparatus). Immunofluorescence experiments with HEK cells, which were transfected with a pcDNA3.1 vector containing the coding sequence of the putative progesterone binding protein shows staining within the cells supporting these results. Additionally, 3H-progesterone binding and glucose-6-phosphatase activity as marker enzyme for endoplasmic reticulum were closely correlated in subcellular fractions of porcine liver cells.

Desmopressin for nocturnal incontinence in the spina bifida population.

PURPOSE: We report our experience with the use of desmopressin in the spina bifida population that is dry during the day but wet at night. MATERIALS AND METHODS: From 1994 to 1996, 18 patients with myelodysplasia were treated with desmopressin for persistent nocturnal enuresis. Initial dose was 40 mcg. before bedtime, decreased by intervals of 10 mcg. every 3 weeks. Patients were kept on the minimum dose required to keep them dry. We reviewed morning catheterized volumes, side effects and dosages needed to stay dry, and compared augmented patients with nonaugmented patients. RESULTS: Of 18 patients 14 (78%) reported marked improvement in nocturnal enuresis. Of 6 augmented patients 5 (83%) are dry compared to 9 of 12 nonaugmented patients (75%). There were no adverse side effects from the use of desmopressin. Average dose to stay dry was 20 mcg. for augmented and 30 mcg. for nonaugmented patients. Of the 4 patients who had persistent nocturnal incontinence despite desmopressin 3 (75%) became dry with a single catheterization in the middle of the night. CONCLUSIONS: Desmopressin is successful in treating nocturnal enuresis in the spina bifida patient with diurnal continence.

Intraepithelial lymphocytes in normal human intestine do not express proteins associated with cytolytic function.

Human small intestine contains a very large population of intraepithelial T lymphocytes (IELs) that are oligoclonal, appear functionally to be cytolytic T cells, and may contribute to the normal and pathological turnover of intestinal epithelial cells. This report addresses the cytolytic function of IELs in normal small intestine by examining their expression of molecules that carry out cell-mediated cytolysis. Immunohistochemical analyses of granzyme B, perforin, Fas ligand, and tumor necrosis factor-alpha demonstrated these proteins were not expressed by small intestinal IELs in situ. These proteins also were not expressed by colonic IELs or by lamina propria lymphocytes in the small or large intestine. Granzyme A, however, was expressed by a large fraction of IELs. In contrast to these in situ results, isolated and in vitro activated IELs were shown to express effector proteins consistent with cytolytic T cells, including granzyme B, Fas ligand, tumor necrosis factor-alpha, and interferon-gamma. These results are most consistent with the vast majority of IELs in normal human small intestine being resting cytolytic T cells and suggest that these cells do not contribute to the apoptotic cell death of epithelial cells in normal intestine.

Human T cells expressing an invariant V alpha 24-J alpha Q TCR alpha are CD4- and heterogeneous with respect to TCR beta expression.

A population of mature CD4-CD8-double-negative T cells that expresses an invariant Valpha24-JalphaQ TCR has been identified in humans; the majority of these cells appear to express Vbeta11. A closely related in variant TCRalpha chain is also expressed by a population of NK1+ murine T cells, but these cells may be either CD4+ or double negative. In this report, multiple CD4+ or double-negative Valpha24+Vbeta11+ T-cell clones were isolated, and only the double-negative clones were found to express the invariant TCRalpha chain. Studies of TCRbeta chains expressed by these cells demonstrate that a subset in some donors use Vbeta genes other than Vbeta11. Characterization of Vbeta11 TCRs in one donor by CDR3-length analysis was also carried out. The results indicate that multiple Vbeta11 TCRs of differing CDR3 lengths may associate with the invariant TCRalpha chain.

Structure and function of the CD1 family of MHC-like cell surface proteins.

The CD1 family of proteins are structurally related to MHC class I proteins, but are only distantly related to the class I proteins or other MHC-linked class I-like proteins. Sequence comparisons indicate that the CD1 proteins have evolved into two subfamilies, those which are similar to human CD1a, b, and c and those which are similar to human CD1d. The CD1A-, B-, and C-like genes were deleted from rodents and the CD1D gene was duplicated. CD1a, b, and c are expressed by thymocytes, dendritic cells, activated monocytes, and B cells (CD1c), a tissue distribution which strongly suggests a role in antigen presentation. In contrast, CD1d and its murine homologues are expressed by many cells outside of the lymphoid and myeloid lineages. The CD1 proteins are in most cases expressed as beta 2mg-associated membrane glycoproteins, but may associate with additional proteins. CD1d is expressed on the surface of intestinal epithelial cells in a nonglycosylvated form without beta 2mg. Whether the CD1 proteins function as antigen-presenting molecules is unresolved, but it is unlikely that they present conventional peptide antigens. Strong evidence indicates that murine CD1 proteins are recognized by a population of NK1.1+, CD4+ or CD4-CD8- (double negative, DN) T cells which express an invariant TCR alpha chain. CD1d is most likely recognized by the homologous T cell population in humans. DN alpha beta T cells which recognize CD1a, b, or c have been isolated, including clones which recognize a lipid antigen from mycobacteria presented by CD1b. A third potential population of CD1 reactive cells are CD8+ T cells in the intestinal epithelium. Taken together, these observations indicate that CD1 proteins interact with several specialized populations of T cells. The precise biological functions mediated through these interactions remain to be determined.

Biochemical and morphological changes that characterise recovery from necrotising biliary pancreatitis in the opossum.

The events that characterise recovery from severe biliary pancreatitis have not been defined. This study used a reversible model of necrotising pancreatitis, induced by obstructing the opossum common bile pancreatic duct (CBPD), to evaluate this phenomenon. The CBPD of opossums was obstructed with a balloon tipped catheter for five days and then decompressed by removal of the catheter. Recovery was evaluated 0-90 days after relief of obstruction. Serum bilirubin and amylase values rapidly declined, reaching control values 7-14 days after removal of the obstructing catheter. Pancreatic protein and amylase values were transiently increased shortly after relief of obstruction but returned to control values 21 days after decompression. Pancreatic ornithine decarboxylase activity and incorporation of [3H]-thymidine into DNA were transiently increased 14 days after duct decompression suggesting that regeneration occurs at approximately that time. Foci of pancreatic necrosis involved roughly 40% of the gland at time of decompression but these foci gradually disappeared and the gland resembled that of control animals 60 days after decompression. Evidence of fibrosis or collagen deposition in the pancreas was not noted at any time. These studies show that recovery after necrotising biliary pancreatitis occurs comparatively rapidly and the restitution ad integrum occurs. Recovery from necrotising acute pancreatitis in this model is not associated with the development of chronic pancreatitis.

Intravenous contrast medium does not increase the severity of acute necrotizing pancreatitis in the opossum.

Contrast-enhanced computed tomography provides diagnostic and prognostic information in patients with acute pancreatitis. To evaluate whether contrast medium may worsen the severity of acute pancreatitis, we have used a model of necrotizing pancreatitis induced by ligating the common bile-pancreatic duct in opossums. Animals were infused with either saline or an ionic contrast agent 48 and 96 hr after induction of pancreatitis. Hyperamylasemia, pancreatic edema, acinar cell fragility, and macroscopic evidence of pancreatitis were comparable in both experimental groups. The microscopic extent of inflammation was similar in both groups, whereas acinar cell injury/necrosis was less in the contrast group. We conclude that administration of this ionic contrast agent during early stages of necrotizing pancreatitis in the opossum does not worsen the disease severity. The concept that administration of contrast medium during early stages of pancreatitis is dangerous should not be accepted until additional experimental and clinical studies support its validity.

Evaluation of necrotizing pancreatitis in the opossum by dynamic contrast-enhanced computed tomography: correlation between radiographic and morphologic changes.

BACKGROUND: The ability to quantitate the extent of acinar cell necrosis with contrast-enhanced computed tomography (CT) during acute pancreatitis is uncertain. STUDY DESIGN: Acute hemorrhagic necrotizing pancreatitis was induced in opossums by obstructing their biliopancreatic duct for up to seven days or by retrograde injection of a bile-trypsin taurocholate mixture into the opossum pancreatic duct. At selected times, groups of three animals each were examined by dynamic contrast-enhanced CT, and the abnormalities on the images were quantitated. Immediately following CT, the animals were sacrificed and the extent of necrosis was quantitated by morphometric analysis of tissue samples at the light microscope level. RESULTS: The CT severity score as well as the degree of nonenhancement on dynamic contrast-enhanced CT were both closely correlated with the extent of acinar cell necrosis (r = 0.91 and r = 0.97, respectively). CONCLUSIONS: The degree of pancreatic nonenhancement on dynamic contrast-enhanced CT can be used to quantitate the extent of pancreatic necrosis during acute necrotizing pancreatitis.