Sex chromosome transformation and the origin of a male-specific X chromosome in the creeping vole

The mammalian sex chromosome system (XX female/XY male) is ancient and highly conserved. The sex chromosome karyotype of the creeping vole (Microtus oregoni) represents a long-standing anomaly, with an X chromosome that is unpaired in females (X0) and exclusively maternally transmitted. We produced a highly contiguous male genome assembly, together with short-read genomes and transcriptomes for both sexes. We show that M. oregoni has lost an independently segregating Y chromosome and that the male-specific sex chromosome is a second X chromosome that is largely homologous to the maternally transmitted X. Both maternally inherited and male-specific sex chromosomes carry fragments of the ancestral Y chromosome. Consequences of this recently transformed sex chromosome system include Y-like degeneration and gene amplification on the male-specific X, expression of ancestral Y-linked genes in females, and X inactivation of the male-specific chromosome in male somatic cells. The genome of M. oregoni elucidates the processes that shape the gene content and dosage of mammalian sex chromosomes and exemplifies a rare case of plasticity in an ancient sex chromosome system.

Safety and Immunogenicity of Different Formulations of a Tetravalent Dengue Purified Inactivated Vaccine in Healthy Adults from Puerto Rico: Final Results after 3 Years of Follow-Up from a Randomized, Placebo-Controlled Phase I Study

Four formulations of an investigational tetravalent dengue purified inactivated vaccine, administered as two doses one month (M) apart, were previously shown to be immunogenic and well-tolerated up to M13 of the phase I study NCT01702857. Here, we report results of the follow-up from M14 to year (Y) 3. One hundred healthy Puerto Rican adults, predominantly dengue virus (DENV)–primed, were randomized 1:1:1:1:1 to receive placebo or vaccine formulations: 1 μg/serotype/dose adjuvanted with aluminum, AS01_E or AS03_B, or aluminum-adjuvanted 4 μg/serotype/dose. No serious adverse events occurred. Two medically-attended potential immune-mediated disease cases, vaccination unrelated, were reported (groups 1 µg+Alum and 1 µg+AS03_B). Of 14 instances of suspected dengue, none were laboratory confirmed. Geometric mean neutralizing antibody titers against DENV 1-4 waned from M14, but remained above pre-vaccination levels for DENV 1-3, with the highest values for group 1 µg+AS03_B: 1220.1, 920.5, 819.4, and 940.5 (Y2), and 1329.3, 1169.2, 1219.8, and 718.9 (Y3). All formulations appeared to be safe and immunogenic during the 3-year follow-up.

Effects of trapping effort and trap placement on estimating abundance of Humboldt's flying squirrels

Live trapping is a common tool used to assess demography of small mammals. However, live-trapping is often expensive and stressful to captured individuals. Thus, assessing the relative tradeoffs among study goals, project expenses, and animal well-being is necessary. Here, we evaluated how apparent bias and precision of estimates for apparent annual survival, abundance, capture probability, and recapture probability of Humboldt’s flying squirrels (Glaucomys oregonensis) varied with the number of secondary trapping occasions. We used data from forested sites trapped on 12 consecutive occasions annually in the HJ Andrews Experimental Forest (9 sites, 6 years) and the Siuslaw National Forest (seven sites, three years) in Oregon. We used Huggins robust design models to estimate parameters of interest for the first 4, 8, and 12 trapping occasions. We also estimated the effect of attaching Tomahawk traps to tree boles on site- and year-specific flying squirrel capture frequencies. Our estimates with 12 occasions were similar to those from previous studies. Abundances and capture probabilities were variable among years on both sites; however, variation was much lower on the Siuslaw sites. Reducing the length of primary trapping occasions from 12 to 8 nights had very little impact on parameter estimates, but further reducing the length of primary trapping occasions to four nights caused substantial apparent bias in parameter estimates and decreased precision. We found that attaching Tomahawk traps to tree boles increased the site- and year-specific capture frequency of flying squirrels. Our results suggest that live-trapping studies targeting Humboldt’s flying squirrels in the Pacific Northwest of the United States could reduce per-site costs and stress to captured individuals without biasing estimates by reducing the length of primary trapping occasions to 8 nights. We encourage similar analyses for other commonly-trapped species in these and other ecosystems.

Prognostic Value of Occult Isolated Tumour Cells within Regional Lymph Nodes of Dogs with Malignant Mammary Tumours

Canine mammary tumours (CMTs) are the most common type of neoplasm in bitches. As in women, the presence of metastasis in regional lymph nodes is an important prognostic factor in bitches with mammary carcinomas, but the clinical significance of occult isolated tumour cells (ITCs) within lymph nodes is still undefined in this species. The effectiveness of immunohistochemistry (IHC) in identifying occult ITCs and micrometastasis (MIC) was compared with that of the conventional haematoxylin and eosin staining technique. The relationship between tumour size, histological type, histological grade and the presence of metastasis was evaluated. The overall survival (OS) of female dogs with occult mammary carcinomas and ITCs within lymph nodes was analysed. Fragments of mammary carcinoma and regional lymph nodes of 59 female dogs were also evaluated. Histological sections of mammary carcinoma and lymph node samples were studied for tumour diagnosis and lymph node samples were tested by IHC using a pan-cytokeratin antibody. It was found that 35.2% of occult ITCs and 2.8% of hidden MIC were detected when IHC was used. There was a good correlation between the size of the tumour and metastasis to the lymph nodes (P = 0.77). ITCs were observed more frequently in the medullary region (60.7%) and metastases in the cortical region (44.4%). There was no significant difference in the OS between female dogs with occult ITCs and lymph nodes without ITCs. IHC can detect occult tumour cells in lymph nodes that are negative by histopathological examination. Female dogs with nodal ITCs do not have lower survival.

A distinct biomolecular profile identifies monoclonal mast cell disorders in patients with idiopathic anaphylaxis

BACKGROUND

Clonal mast cell disorders are known to occur in a subset of patients with systemic reactions to Hymenoptera stings. This observation has prompted the question of whether clonal mast cell disorders also occur in patients with idiopathic anaphylaxis (IA).

OBJECTIVE

We sought to determine the prevalence of clonal mast cell disorders among patients with IA, criteria to identify those patients who require a bone marrow biopsy, and whether the pathogenesis of IA involves a hyperresponsive mast cell compartment.

METHODS

We prospectively enrolled patients with IA (≥3 episodes/y) who then underwent a medical evaluation that included a serum tryptase determination, allele-specific quantitative PCR (ASqPCR) for the KIT D816V mutation, and a bone marrow examination. Mast cells were cultured from peripheral blood CD34⁺ cells and examined for releasability after FcεRI aggregation.

RESULTS

Clonal mast cell disease was diagnosed in 14% of patients referred with IA. ASqPCR for the KIT D816V mutation was a useful adjunct in helping identify those with systemic mastocytosis but not monoclonal mast cell activation syndrome. A modified overall clonal prediction model was developed by using clinical findings, a serum tryptase determination, and ASqPCR. There was no evidence of a hyperresponsive mast cell phenotype in patients with IA.

CONCLUSION

Patients with clonal mast cell disease can present as having IA. Distinct clinical and laboratory features can be used to select those patients more likely to have an underlying clonal mast cell disorder (monoclonal mast cell activation syndrome or systemic mastocytosis) and thus candidates for a bone marrow biopsy.

Elevated basal serum tryptase identifies a multisystem disorder associated with increased TPSAB1 copy number

Elevated basal serum tryptase levels are present in 4-6% of the general population, but the cause and relevance of such increases are unknown. Previously, we described subjects with dominantly inherited elevated basal serum tryptase levels associated with multisystem complaints including cutaneous flushing and pruritus, dysautonomia, functional gastrointestinal symptoms, chronic pain, and connective tissue abnormalities, including joint hypermobility. Here we report the identification of germline duplications and triplications in the TPSAB1 gene encoding α-tryptase that segregate with inherited increases in basal serum tryptase levels in 35 families presenting with associated multisystem complaints. Individuals harboring alleles encoding three copies of α-tryptase had higher basal serum levels of tryptase and were more symptomatic than those with alleles encoding two copies, suggesting a gene-dose effect. Further, we found in two additional cohorts (172 individuals) that elevated basal serum tryptase levels were exclusively associated with duplication of α-tryptase-encoding sequence in TPSAB1, and affected individuals reported symptom complexes seen in our initial familial cohort. Thus, our findings link duplications in TPSAB1 with irritable bowel syndrome, cutaneous complaints, connective tissue abnormalities, and dysautonomia.

Bright focused ion beam sources based on laser-cooled atoms

Nanoscale focused ion beams (FIBs) represent one of the most useful tools in nanotechnology, enabling nanofabrication via milling and gas-assisted deposition, microscopy and microanalysis, and selective, spatially resolved doping of materials. Recently, a new type of FIB source has emerged, which uses ionization of laser cooled neutral atoms to produce the ion beam. The extremely cold temperatures attainable with laser cooling (in the range of 100 μK or below) result in a beam of ions with a very small transverse velocity distribution. This corresponds to a source with extremely high brightness that rivals or may even exceed the brightness of the industry standard Ga+ liquid metal ion source. In this review we discuss the context of ion beam technology in which these new ion sources can play a role, their principles of operation, and some examples of recent demonstrations. The field is relatively new, so only a few applications have been demonstrated, most notably low energy ion microscopy with Li ions. Nevertheless, a number of promising new approaches have been proposed and/or demonstrated, suggesting that a rapid evolution of this type of source is likely in the near future.

Impaired function of bone marrow stromal cells in systemic mastocytosis

Patients with systemic mastocytosis (SM) have a wide variety of problems, including skeletal abnormalities. The disease results from a mutation of the stem cell receptor (c-kit) in mast cells and we wondered if the function of bone marrow stromal cells (BMSCs; also known as MSCs or mesenchymal stem cells) might be affected by the invasion of bone marrow by mutant mast cells. As expected, BMSCs from SM patients do not have a mutation in c-kit, but they proliferate poorly. In addition, while osteogenic differentiation of the BMSCs seems to be deficient, their adipogenic potential appears to be increased. Since the hematopoietic supportive abilities of BMSCs are also important, we also studied the engraftment in NSG mice of human CD34(+) hematopoietic progenitors, after being co-cultured with BMSCs of healthy volunteers vs. BMSCs derived from patients with SM. BMSCs derived from the bone marrow of patients with SM could not support hematopoiesis to the extent that healthy BMSCs do. Finally, we performed an expression analysis and found significant differences between healthy and SM derived BMSCs in the expression of genes with a variety of functions, including the WNT signaling, ossification, and bone remodeling. We suggest that some of the symptoms associated with SM might be driven by epigenetic changes in BMSCs caused by dysfunctional mast cells in the bone marrow of the patients.

Restoration of riparian areas following the removal of cattle in the northwestern great basin

We assessed the effects of the elimination of livestock in riparian systems at Hart Mountain National Antelope Refuge in southeastern Oregon, 23 years after the removal of cattle grazing, using 64 photos taken before grazing was removed compared with later retake photos. Two methods were used for this assessment: (1) a qualitative visual method comparing seven cover types and processes and (2) a new quantitative method of inserting digital line transects into photos. Results indicated that channel widths and eroding banks decreased in 64 and 73% of sites, respectively. We found a 90% decrease in the amount of bare soil (P < 0.001) and a 63% decrease in exposed channel (P < 0.001) as well as a significant increase in the cover of grasses/sedges/forbs (15% increase, P = 0.037), rushes (389% increase, P = 0.014), and willow (388% increase, P < 0.001). We also assessed the accuracy of the new method of inserting digital line transects into photo pairs. An overall accuracy of 91% (kappa 83%) suggests that digital line transects can be a useful tool for quantifying vegetation cover from photos. Our results indicate that the removal of cattle can result in dramatic changes in riparian vegetation, even in semi-arid landscapes and without replanting or other active restoration efforts.

Mastocytosis associated with a rare germline KIT K509I mutation displays a well-differentiated mast cell phenotype

BACKGROUND

Mastocytosis associated with germline KIT activating mutations is exceedingly rare. We report the unique clinicopathologic features of a patient with systemic mastocytosis caused by a de novo germline KIT K509I mutation.

OBJECTIVES

We sought to investigate the effect of the germline KIT K509I mutation on human mast cell development and function.

METHODS

Primary human mast cells derived from CD34(+) peripheral blood progenitors were examined for growth, development, survival, and IgE-mediated activation. In addition, a mast cell transduction system that stably expressed the KIT K509I mutation was established.

RESULTS

KIT K509I biopsied mast cells were round, CD25(-), and well differentiated. KIT K509I progenitors cultured in stem cell factor (SCF) demonstrated a 10-fold expansion compared with progenitors from healthy subjects and developed into mature hypergranular mast cells with enhanced antigen-mediated degranulation. KIT K509I progenitors cultured in the absence of SCF survived but lacked expansion and developed into hypogranular mast cells. A KIT K509I mast cell transduction system revealed SCF-independent survival to be reliant on the preferential splicing of KIT at the adjacent exonic junction.

CONCLUSION

Germline KIT mutations associated with mastocytosis drive a well-differentiated mast cell phenotype distinct to that of somatic KIT D816V disease, the oncogenic potential of which might be influenced by SCF and selective KIT splicing.

KIT GNNK splice variants: expression in systemic mastocytosis and influence on the activating potential of the D816V mutation in mast cells

Stem cell factor-dependent KIT activation is an essential process for mast cell homeostasis. The two major splice variants of KIT differ by the presence or absence of four amino acids (GNNK) at the juxta-membrane region of the extracellular domain. We hypothesized that the expression pattern of these variants differs in systemic mastocytosis and that transcripts containing the KIT D816V mutation segregate preferentially to one GNNK variant. A quantitative real-time PCR assay to assess GNNK(-) and GNNK(+) transcripts from bone marrow mononuclear cells was developed. The GNNK(-)/GNNK(+) copy number ratio showed a trend toward a positive correlation with the percentage of neoplastic mast cell involvement, and KIT D816V containing transcripts displayed a significantly elevated GNNK(-)/GNNK(+) copy number ratio. Relative expression of only the GNNK(-) variant correlated with increasing percentage of neoplastic mast cell involvement. A mast cell transfection system revealed that the GNNK(-) isoform of wild type KIT was associated with increased granule formation, histamine content, and growth. When accompanying the KIT D816V mutation, the GNNK(-) isoform enhanced cytokine-free metabolism and moderately reduced sensitivity to the tyrosine kinase inhibitor, PKC412. These data suggest that neoplastic mast cells favor a GNNK(-) variant predominance, which in turn enhances the activating potential of the KIT D816V mutation and thus could influence therapeutic sensitivity in systemic mastocytosis.

Targeting the KIT activating switch control pocket: a novel mechanism to inhibit neoplastic mast cell proliferation and mast cell activation

Activating mutations in the receptor tyrosine kinase KIT, most notably KIT D816V, are commonly observed in patients with systemic mastocytosis. Thus, inhibition of KIT has been a major focus for treatment of this disorder. Here we investigated a novel approach to such inhibition. Utilizing rational drug design, we targeted the switch pocket (SP) of KIT which regulates its catalytic conformation. Two SP inhibitors thus identified, DP-2976 and DP-4851, were examined for effects on neoplastic mast cell proliferation and mast cell activation. Autophosphorylation of both wild type (WT) and, where also examined, KIT D816V was blocked by these compounds in transfected 293T cells, HMC 1.1 and 1.2 human mast cell lines; and in CD34⁺-derived human mast cells activated by stem cell factor (SCF). Both inhibitors induced apoptosis in the neoplastic mast cell lines and reduced survival of primary bone marrow mast cells from patients with mastocytosis. Moreover, the SP inhibitors more selectively blocked SCF potentiation of FcεRI-mediated degranulation. Overall, SP inhibitors represent an innovative mechanism of KIT inhibition whose dual suppression of KIT D816V neoplastic mast cell proliferation and SCF enhanced mast cell activation may provide significant therapeutic benefits.

IL-5 receptor α levels in patients with marked eosinophilia or mastocytosis

BACKGROUND

IL-5 plays a central role in the development and maintenance of eosinophilia (EO) and eosinophil activation in a wide variety of eosinophilic disorders. Although IL-5, IL-3, and GM-CSF can modulate the expression of IL-5 receptor α (IL-5Rα) on eosinophils in vitro, little is known about soluble and surface IL-5Rα levels in vivo.

OBJECTIVE

To assess soluble and surface IL-5Rα levels in patients with EO and/or mastocytosis.

METHODS

Surface IL-5Rα expression was assessed by flow cytometry in blood and/or bone marrow from subjects with EO (n = 39) and systemic mastocytosis (n = 8) and from normal volunteers (n = 28). Soluble IL-5Rα (sIL-5Rα) level was measured in a cohort of 177 untreated subjects and correlated with EO, eosinophil activation, and serum tryptase and cytokine levels.

RESULTS

IL-5Rα expression on eosinophils inversely correlated with EO (r = -0.48; P < .0001), whereas serum levels of sIL-5Rα increased with the eosinophil count (r = 0.56; P < .0001) and serum IL-5 (r = 0.40; P < .0001) and IL-13 (r = 0.29; P = .004) levels. Of interest, sIL-5Rα level was significantly elevated in patients with systemic mastocytosis without EO. Although sIL-5Rα levels correlated with serum tryptase levels in these patients, eosinophil activation, assessed by CD69 expression on eosinophils and serum eosinophil-derived neurotoxin levels, was increased compared with that in normal subjects.

CONCLUSIONS

These data are consistent with an in vivo IL-5Rα regulatory pathway in human eosinophils similar to that described in vitro and involving a balance between soluble and surface receptor levels. This may have implications with respect to the use of novel therapeutic agents targeting IL-5 and its receptor in patients with EO and/or mastocytosis.

Clonal analysis of NRAS activating mutations in KIT-D816V systemic mastocytosis

Cooperating genetic events are likely to contribute to the phenotypic diversity of KIT-D816V systemic mastocytosis. In this study, 44 patients with KIT-D816V systemic mastocytosis were evaluated for coexisting NRAS, KRAS, HRAS or MRAS mutations. Activating NRAS mutations were identified in 2 of 8 patients with advanced disease. NRAS mutations were not found in patients with indolent systemic mastocytosis. To better understand the clonal evolution of mastocytosis, we evaluated the cell compartments impacted by the NRAS and KIT mutations. Clonal mast cells harbored both mutations. KIT-D816V was not detected in bone marrow CD34(+) progenitors, whereas the NRAS mutation was present. These findings suggest that NRAS mutations may have the potential to precede KIT-D816V in clonal development. Unlike other mature lineages, mast cell survival is dependent on KIT and the presence of these two activating mutations may have a greater impact on the expansion of this cell compartment and in resultant disease severity.

ON THE CHEMISTRY AND STAINING PROPERTIES OF CERTAIN DERIVATIVES OF THE METHYLENE BLUE GROUP WHEN COMBINED WITH EOSIN

1. Eosinate of thionin gives very satisfactory staining for blood smears. It is easily prepared and dissolves readily in methylated spirits. 2. In the methods heretofore employed for making mixtures of eosin and methylene blue derivatives, the eosinates of methylene violet and methylene azure are present in very small quantities or are altogether absent. 3. Thionol and thionin are probably formed in methylene blue which has been long boiled with dilute alkalies and silver oxide. 4. Good stains of eosin and methylene blue derivatives can be obtained by a variety of manipulations. 5. Methylated spirits is more economical as a solvent for this stain and better adapted for the simple technique above described than is methyl alcohol. There is some evidence that the staining act is of a chemical nature.

Alpha 2-macroglobulin capture allows detection of mast cell chymase in serum and creates a reservoir of angiotensin II-generating activity

Human chymase is a highly efficient angiotensin II-generating serine peptidase expressed by mast cells. When secreted from degranulating cells, it can interact with a variety of circulating antipeptidases, but is mostly captured by alpha(2)-macroglobulin, which sequesters peptidases in a cage-like structure that precludes interactions with large protein substrates and inhibitors, like serpins. The present work shows that alpha(2)-macroglobulin-bound chymase remains accessible to small substrates, including angiotensin I, with activity in serum that is stable with prolonged incubation. We used alpha(2)-macroglobulin capture to develop a sensitive, microtiter plate-based assay for serum chymase, assisted by a novel substrate synthesized based on results of combinatorial screening of peptide substrates. The substrate has low background hydrolysis in serum and is chymase-selective, with minimal cleavage by the chymotryptic peptidases cathepsin G and chymotrypsin. The assay detects activity in chymase-spiked serum with a threshold of approximately 1 pM (30 pg/ml), and reveals native chymase activity in serum of most subjects with systemic mastocytosis. alpha(2)-Macroglobulin-bound chymase generates angiotensin II in chymase-spiked serum, and it appears in native serum as chymostatin-inhibited activity, which can exceed activity of captopril-sensitive angiotensin-converting enzyme. These findings suggest that chymase bound to alpha(2)-macroglobulin is active, that the complex is an angiotensin-converting enzyme inhibitor-resistant reservoir of angiotensin II-generating activity, and that alpha(2)-macroglobulin capture may be exploited in assessing systemic release of secreted peptidases.

Vibro-acoustography imaging of permanent prostate brachytherapy seeds in an excised human prostate--preliminary results and technical feasibility

OBJECTIVE

The objective in this work is to investigate the feasibility of using a new imaging tool called vibro-acoustography (VA) as a means of permanent prostate brachytherapy (PPB) seed localization to facilitate post-implant dosimetry (PID).

METHODS AND MATERIALS

Twelve OncoSeed (standard) and eleven EchoSeed (echogenic) dummy seeds were implanted in a human cadaver prostate. Seventeen seeds remained after radical retropubic prostatectomy. VA imaging was conducted on the prostate that was cast in a gel phantom and placed in a tank of degassed water. 2-D magnitude and phase VA image slices were obtained at different depths within the prostate showing location and orientation of the seeds.

RESULTS

VA demonstrates that twelve of seventeen (71%) seeds implanted were visible in the VA image, and the remainder were obscured by intra-prostatic calcifications. Moreover, it is shown here that VA is capable of imaging and locating PPB seeds within the prostate independent of seed orientation, and the resulting images are speckle free.

CONCLUSION

The results presented in this research show that VA allows seed detection within a human prostate regardless of their orientation, as well as imaging intra-prostatic calcifications.

The kinetics of swelling of southern bean mosaic virus: a study using photon correlation spectroscopy

Southern bean mosaic virus swells upon removal of Ca2+ at pH 8.25. Virions do not seem to aggregate significantly; the z-average hydrodynamic diameter increases from 29.9 nm to 44.0 nm. Swelling is virtually complete within 3 min, and swollen virions have a z-average hydrodynamic diameter similar to that of virions swollen by dialysis overnight.

Southern bean mosaic virus-specific proteins are synthesized in an in vitro system supplemented with intact, treated virions

RNA encapsidated in icosahedral particles of southern bean mosaic virus (SBMV) can act as a template for protein synthesis in an mRNA-dependent rabbit reticulocyte cell-free translation system, following dialysis of virions against mildly alkaline buffers. Exposure of the SBMV RNA template occurs only after addition of virus particles to the translation system and appears not to involve complete disruption of the protective SBMV capsid.

Activity of imatinib in systemic mastocytosis with chronic basophilic leukemia and a PRKG2-PDGFRB fusion

BACKGROUND

Translocations involving region 5q31-32 (PDGFRB) have been reported in a variety of myeloproliferative diseases and are often associated with significant peripheral eosinophilia. We report an unusual case of a patient presenting with peripheral basophilia and systemic mastocytosis in whom cytogenetic analysis revealed a t(4;5)(q21.1;q31.3).

DESIGN AND METHODS

We used molecular analyses to determine the role of PDGFRB in this case. The patient was treated with imatinib.

RESULTS

Fluorescence in situ hybridization (FISH) documented a breakpoint in PDGFRB. In agreement with this, the patient responded very well to imatinib with resolution of clinical symptoms, basophilia, and mast cell disease. Molecular analyses revealed that PDGFRB, encoding an imatinib-sensitive tyrosine kinase, was fused to PRKG2. The fusion gene incorporates the first two exons of PRKG2 fused to the truncated exon 12 of PDGFRB, resulting in the disruption of its juxtamembrane domain. Functional studies confirmed that the activity and transforming properties of PRKG2-PDGFRbeta were dependent on the disruption of the auto-inhibitory juxtamembrane domain.

CONCLUSIONS

Our results identify a second case of the PRKG2-PDGFRB fusion and confirm the unusual PDGFRB breakpoint associated with this fusion. This work also illustrates the use of imatinib for the treatment of specific cases of systemic mastocytosis.

The mast cell and allergic diseases: role in pathogenesis and implications for therapy

Mast cells have long been recognized for their role in the genesis of allergic inflammation; and more recently for their participation in innate and acquired immune responses. Mast cells reside within tissues including the skin and mucosal membranes, which interface with the external environment; as well as being found within vascularized tissues next to nerves, blood vessels and glandular structures. Mast cells have the capability of reacting both within minutes and over hours to specific stimuli, with local and systemic effects. Mast cells express the high affinity IgE receptor (FcepsilonRI) and upon aggregation of FcepsilonRI by allergen-specific IgE, mast cells release and generate biologically active preformed and newly synthesized mediators which are involved in many aspects of allergic inflammation. While mast cells have been well documented to be essential for acute allergic reactions, more recently the importance of mast cells in reacting through pattern recognition receptors in innate immune responses has become recognized. Moreover, as our molecular understanding of the mast cell has evolved, novel targets for modulation have been identified with promising therapeutic potential.

Treatment of Systemic Mastocytosis

It is an exciting time in the treatment of systemic mastocytosis. Major advances in the past 2 decades have helped to define the molecular abnormalities associated with this disease and to delineate pathways involved in its pathogenesis. This has directly translated into the development of novel targeted therapies. These therapies hold great promise to patients and health care providers that a "cure" for systemic mastocytosis may someday be obtainable.

Microbial forensics for natural and intentional incidents of infectious disease involving animals

Microbial forensics is a relatively new scientific discipline dedicated to analysing microbiological evidence from a crime for attribution purposes. It builds on traditional microbiology and epidemiology but within a legal framework. Important motives for forensic investigations include interdiction of criminals, prosecution of justice, and ideally, deterrence of others from committing similar acts. Forensic capabilities in animal health should focus on building capacity for detection and reporting of increases in infectious disease morbidity and mortality among animals that might reflect a covert release of a pathogen. Suspicion should be raised when epidemiological patterns are different from those expected for the animal population and the pathogen in question. Existing capacities for the detection and reporting of epidemic and even endemic diseases should be an international priority for the prevention of catastrophic losses in animal and potentially in human life. The veterinary community needs to be more aware of the legal requirements related to forensic investigations so that veterinarians will be prepared to handle evidence properly within their own fields.

Agroterrorism, biological crimes, and biowarfare targeting animal agriculture. The clinical, pathologic, diagnostic, and epidemiologic features of some important animal diseases

In the past 100 years, to our knowledge there have been approximately 12 events involving the intentional introduction of microbiologic agents into livestock and animal populations worldwide, of which three were World War I events in the United States. To the best of the authors' knowledge, there has been no recent intentional introduction of microbiologic agents (viruses or bacteria) into livestock and animal populations in the United States. The criminal or terrorist use of chemicals against animals and agriculture products have been more common. With the political, economic, and military new world order, however, the United States must maintain a vigilant posture. The framework for this vigilance must be an intelligence system sensitive to the needs of agriculture and a first-class animal disease diagnostic surveillance and response system.

Participation in voluntary individual savings accounts: an analysis of IRAs, 401(k)s, and the TSP

New voluntary individual savings accounts have been proposed by some as a part of, or in addition to, Social Security. The success of these proposals would depend greatly on how many workers participate. This paper compares participation rates in three existing voluntary individual account-type plans--Individual Retirement Accounts (IRAs), 401(k)s, and the federal Thrift Savings Plan (TSP)--to clarify expectations about who might participate in a voluntary individual account system. It finds that participants in IRAs, 401(k)s, and the TSP tend to be disproportionately male, higher earners, older, full-time workers, and either white or nonblack minorities compared with the population at large. Differences in earnings explain much of the difference between participation rates of men and women, however, but less of the difference between participation rates of workers of different races. Whether participation in a new system of voluntary individual accounts would resemble participation in IRAs, 401(k)s, or the TSP would depend on a number of factors. For instance, the population covered by 401(k)s and the TSP is much smaller than that covered by Social Security. Average earnings are also higher among 401(k) and TSP participants than for workers covered by Social Security, which, based on these findings, suggests that participation rates could be lower in a universal system. Participation would also depend on many other factors, however, such as the extent of matching contributions or other financial incentives, the investment options available, and the amount of education provided to potential participants.

Proximity of prostate cancer to the urethra: implications for minimally invasive ablative therapies

OBJECTIVES

The delivery of thermotherapy, cryotherapy, and interstitial radiation with minimal morbidity is dependent on the preservation of the prostatic urethra. Our aim was to determine the distribution of the distance between the urethra and the nearest prostate cancer.

METHODS

We determined the location of cancer in 350 prostate cancers treated by radical prostatectomy between 1991 and 1993. Each pathologic specimen was totally embedded, serially sectioned, and whole mounted. For each prostate, the radial distance from the urethra to the nearest cancer was determined (urethral-cancer distance). The urethra-cancer distance was correlated with the clinical, pathologic, and laboratory factors. Univariate and multivariate associations with progression-free survival were determined.

RESULTS

The mean follow-up was 6.1 years. Ninety-three patients had biochemical, local, or systemic cancer recurrence. The mean +/- SD distance from the urethra to the nearest cancer was 3 +/- 3 mm (range 0 to 18). In 58 patients (17%), the cancer touched the urethra. A decreasing urethra-cancer distance was associated with increasing rates of cancer recurrence (P = 0.009). The urethra-cancer distance correlated with each of the following preoperative factors: preoperative prostate-specific antigen (r = -0. 22, P <0.001), Gleason score in biopsy specimen (r = -0.13, P = 0.02), and percentage of Gleason score 4 or 5 in the biopsy specimen (r = -0.17, P = 0.008).

CONCLUSIONS

The distance between the urethra and the nearest cancer was associated with prostate cancer outcome. Many patients have cancer close to the urethra. This finding may have implications for nonsurgical ablative therapies for prostate cancer.

Treatment of extraprostatic cancer in clinically organ-confined prostate cancer by permanent interstitial brachytherapy: is extraprostatic seed placement necessary?

PURPOSE

Successful treatment with ultrasound-guided transperineal interstitial permanent prostate brachytherapy (TIPPB) relies on effective radiation coverage of intraprostatic and clinically occult extraprostatic cancer. This study examines prostatectomy findings as they relate to treatment of extraprostatic extension (EPE) of cancer and TIPPB techniques and dosimetry.

MATERIALS AND METHODS

A total of 313 prostatectomy specimens from patients with clinical tumor classification T1-T2b adenocarcinomas, serum prostate-specific antigen <20 ng/mL, and Gleason score <8 were whole mounted and evaluated for intraprostatic cancer volume and extraprostatic radial distance, area of perforation, and cancer density. From these data, extraprostatic cancer volume is calculated and used to estimate extraprostatic tumor control probabilities using the linear quadratic radiobiological model and Poisson statistics. TIPPB dose-gradient characteristics at the prostate periphery are examined.

RESULTS

Intraprostatic cancer volume ranges from 0 to 38 cc, whereas extraprostatic cancer volume ranges from 0 to 4.6 cc (mean 0.06 cc). The radial distance of EPE ranges from 0 to 4.4 mm (mean 0.18 mm). The ratio of extraprostatic to intraprostatic cancer volume ranges from 0% to 18% (mean 0.4%).

CONCLUSIONS

Only small amounts of clinically occult extraprostatic cancer were identified in the majority of specimens with EPE. Tumor control probability calculations suggest that this volume of cancer may be treated effectively with TIPPB. Treatment of this cancer possibly is achieved with an intraprostatic implant, but treatment of all cancers identified in this study suggests that some extraprostatic seed placement is desirable.

Meta-analysis of the age-associated decline in maximal aerobic capacity in men: relation to training status

Based on cross-sectional data, we recently reported that, in contrast to the prevailing view, the rate of decline in maximal oxygen consumption (VO(2 max)) with age is greater in physically active compared with sedentary healthy women. We tested this hypothesis in men using a meta-analytic study of VO(2 max) values in the published literature. A total of 242 studies (538 subject groups and 13,828 subjects) met the inclusion criteria and were arbitrarily separated into sedentary (214 groups, 6,231 subjects), active (159 groups, 5,621 subjects), and endurance-trained (165 groups, 1,976 subjects) populations. Body fat percent increased with age in sedentary and active men (P < 0.001), whereas no change was observed in endurance-trained men. VO(2 max) was inversely and strongly related to age within each population (r = -0.80 to -0.88, all P < 0. 001) and was highest in endurance-trained and lowest in sedentary populations at any age. Absolute rates of decline in VO(2 max) with age were not different (P > 0.05) in sedentary (-4.0 ml. kg(-1). min(-1). decade(-1)), active (-4.0), and endurance-trained (-4.6) populations. Similarly, there were no group differences (P > 0.05) in the relative (%) rates of decline in VO(2 max) with advancing age (-8.7, -7.3, and -6.8%/decade, respectively). Maximal heart rate was inversely related to age within each population (r = -0.88 to -0.93, all P < 0.001), but the rate of age-related reduction was not different among the populations. There was a significant decline in running mileage and speed with advancing age in the endurance-trained men. The present cross-sectional meta-analytic findings do not support the hypothesis that the rate of decline in VO(2 max) with age is related to habitual aerobic exercise status in men.

Cloning and characterization of Drosophila topoisomerase IIIbeta. Relaxation of hypernegatively supercoiled DNA

We cloned cDNA encoding Drosophila DNA topoisomerase III. The top3 cDNA encodes an 875-amino acid protein, which is nearly 60% identical to mammalian topoisomerase IIIbeta enzymes. Similarity between the Drosophila protein and the topoisomerase IIIbetas is particularly striking in the carboxyl-terminal region, where all contain eight highly conserved CXXC motifs not found in other topoisomerase III enzymes. We therefore propose the Drosophila protein is a member of the beta-subfamily of topoisomerase III enzymes. The top3beta gene is a single-copy gene located at 5 E-F on the X chromosome. P-element insertion into the 5'-untranslated region of this gene affects topoisomerase IIIbeta protein levels, but not the overall fertility and viability of the fly. We purified topoisomerase IIIbeta to near homogeneity and observed relaxation activity only with a hypernegatively supercoiled substrate, but not with plasmid DNA directly isolated from bacterial cells. Despite this difference in substrate preference, the degree of relaxation of the hypernegatively supercoiled substrate is comparable to relaxation of plasmid DNA by other type I enzymes. Drosophila topoisomerase IIIbeta forms a covalent linkage to 5' DNA phosphoryl groups, and the DNA cleavage reaction prefers single-stranded substrate over double-stranded, suggesting an affinity of this enzyme for DNA with non-double-helical structure.

Molecular analysis of barley yellow mosaic virus isolates from China

The complete sequences of both RNAs of an isolate of barley yellow mosaic virus from Yancheng, Jiangsu province, China, were determined. The sequences resembled those of an isolate from Japan (96.8% identical nucleotides for RNA1; 95.7% for RNA2) more closely than one from Germany (93.9 and 91.0%, respectively). The greatest differences between the Chinese and Japanese isolates were in the 5'-UTRs of RNAs 1 and 2 (88.9 and 91.6% identical nucleotides, respectively) and there were also some other regions of difference in P1 (RNA2) and P3, CI, NIa and the 5' end of the coat protein (CP) (RNA1). Molecular differences between isolates from ten sites widely distributed in Eastern China were studied by sequencing RNA regions coding for the CP (RNA1) and the N-terminus of the P2 protein (RNA2). The P2 fragment was more variable than the CP, and phylogenetic analysis of both regions showed that Asian and European isolates formed distinct clusters. Differences between isolates were also revealed by single-strand conformation polymorphism of reverse transcription-polymerase chain reaction products, spanning the full lengths of both RNA1 and RNA2. However, molecular variations between isolates could not be linked to earlier results showing differences in cultivar response.

The radial distance of extraprostatic extension of prostate carcinoma: implications for prostate brachytherapy

BACKGROUND

Extraprostatic extension (EPE) is an unfavorable prognostic factor in patients with prostate carcinoma. Prior studies have reported the linear extent of EPE measured circumferentially along the edge of the prostate. In this study, the authors defined and evaluated a novel measure of EPE in a large series of radical prostatectomy specimens. These results have important clinical implications in the management of localized prostate carcinoma by brachytherapy and other modalities.

METHODS

The authors reviewed the preoperative records and biopsy findings from 376 patients who underwent radical retropubic prostatectomy between September 1991 and June 1993. Whole mount radical prostatectomy specimens were examined, and the location of EPE for each specimen was recorded. The radial EPE distance was measured perpendicular to the edge of the prostate. For specimens with multiple EPE sites, the maximum radial EPE distance was recorded. Established eligibility criteria for prostate brachytherapy were evaluated using these results, with emphasis placed on achieving adequate radiation dose coverage 3-5 mm beyond the capsule or the edge of the prostate.

RESULTS

EPE was identified in 105 of 376 specimens (28%) at 248 sites. The radial EPE distance in these specimens had a mean of 0.8 mm (range, 0.04-4.4 mm) and a median of 0.5 mm. Of these 105 patients, the median and mean preoperative prostate specific antigen (PSA) concentrations were 11.8 ng/mL and 17.9 ng/mL, respectively. The mean and range of the Gleason score and prostate volume for all specimens were 6.3 (range, 3-9) and 39 cc (range, 8-294 cc), respectively. In 107 patients who met the selection criteria for prostate brachytherapy eligibility of a PSA level < 10 ng/mL, Gleason score < 7, and gland volume < 60 cc, the maximum and mean radial EPE distances were 0.6 mm and 0.03 mm, respectively.

CONCLUSIONS

The radial distance of EPE is an important measure that influences treatment strategies for patients with localized prostate carcinoma. Currently described criteria for the treatment of early stage prostate carcinoma by brachytherapy alone appear satisfactory to ensure effective radiation dose coverage of EPE of prostate tumors. Treating the prostate with a 3-5 mm margin by brachytherapy would encompass all known tumor in approximately 99% of the specimens examined in this study.

Milestones in the research on tobacco mosaic virus

Beijerinck's (1898) recognition that the cause of tobacco mosaic disease was a novel kind of pathogen became the breakthrough which eventually led to the establishment of virology as a science. Research on this agent, tobacco mosaic virus (TMV), has continued to be at the forefront of virology for the past century. After an initial phase, in which numerous biological properties of TMV were discovered, its particles were the first shown to consist of RNA and protein, and X-ray diffraction analysis of their structure was the first of a helical nucleoprotein. In the molecular biological phase of research, TMV RNA was the first plant virus genome to be sequenced completely, its genes were found to be expressed by cotranslational particle disassembly and the use of subgenomic mRNA, and the mechanism of assembly of progeny particles from their separate parts was discovered. Molecular genetical and cell biological techniques were then used to clarify the roles and modes of action of the TMV non-structural proteins: the 126 kDa and 183 kDa replicase components and the 30 kDa cell-to-cell movement protein. Three different TMV genes were found to act as avirulence genes, eliciting hypersensitive responses controlled by specific, but different, plant genes. One of these (the N gene) was the first plant gene controlling virus resistance to be isolated and sequenced. In the biotechnological sphere, TMV has found several applications: as the first source of transgene sequences conferring virus resistance, in vaccines consisting of TMV particles genetically engineered to carry foreign epitopes, and in systems for expressing foreign genes. TMV owes much of its popularity as a research mode to the great stability and high yield of its particles. Although modern methods have much decreased the need for such properties, and TMV may have a less dominant role in the future, it continues to occupy a prominent position in both fundamental and applied research.

Production of a functional single chain antibody attached to the surface of a plant virus

A potato virus X (PVX) vector was used to express a single chain antibody fragment (scFv) against the herbicide diuron, as a fusion to the viral coat protein. The modified virus accumulated in inoculated Nicotiana clevelandii plants and assembled to give virus particles carrying the antibody fragment. Electron microscopy was used to show that virus particles from infected leaf sap were specifically trapped on grids coated with a diuron-BSA conjugate. The results demonstrate that the PVX vector can be used as a presentation system for functional scFv.

Chaperone protein GrpE and the GroEL/GroES complex promote the correct folding of tobacco mosaic virus coat protein for ribonucleocapsid assembly in vivo

Several prokaryotic chaperone proteins were shown to promote the correct folding and in vivo assembly of tobacco mosaic virus coat protein (TMV CP) using a chimaeric RNA packaging system in control or chaperone-deficient mutant strains of Escherichia coli. Mutations in groEL or dnaK reduced the amount of both total and soluble TMV CP, and the yield of assembled TMV-like particles, several-fold. Thus both GroEL and DnaK have significant direct or indirect effects on the overall expression, stability, folding and assembly of TMV CP in vivo. In contrast, while cells carrying a mutation in grpE expressed TMV CP to a higher overall level than control E. coli, the amounts of both soluble CP and assembled TMV-like particles were below control levels, suggesting a negative effect of GrpE on overall CP accumulation, but positive role(s) in CP folding and assembly. Curiously, cells with mutations in groES and, to a lesser extent, dnaJ expressed total, soluble and assembled forms of TMV CP significantly above control values, suggesting some form of negative control by these chaperone proteins. To avoid pleiotropic effects or artefacts in chaperone-null mutants, selected chaperone proteins were also over-expressed in control E. coli cells. Overproduction of GroEL or GroES alone had little effect. However, co-overexpression of GroEL and GroES resulted in a two-fold increase in soluble TMV CP and a four-fold rise in assembled TMV-like (pseudovirus) particles in vivo. Moreover, TMV CP was shown to interact directly with GroEL in vivo. Together, these results suggest that GrpE and the GroEL/GroES chaperone complex promote the correct folding and assembly of TMV CP into ribonucleocapsids in vivo.

Sarcoplasmic reticulum responses to repeated sprints are affected by conditioning of horses

Sarcoplasmic reticulum (SR) responses to repeated sprints and to physical conditioning were studied in 10 Quarter Horses. Exercise tests (four repeated sprints on a treadmill) were conducted before and after 12 wk of sprint conditioning. Muscle samples from the middle gluteal muscle were taken before and after each exercise test, and SR vesicles were isolated. Calcium uptake was determined spectrophotometrically using antipyrylazo III, and Ca2+-ATPase activity was determined using an enzyme-linked optical assay. Conditioning increased calcium uptake rate and Ca2+-ATPase activity by 14 and 38%, respectively, before exercise and by 25 and 26% after exercise. Exercise decreased calcium uptake rate and Ca2+-ATPase activity by 37 and 27%, respectively, before conditioning and by 28 and 21% after conditioning. Decreases in calcium uptake and Ca2+-ATPase activity of SR have been associated with fatigue during exercise, and this association is strengthened by the moderating effect of conditioning.

Smaller differences in total and regional adiposity with age in women who regularly perform endurance exercise

Our aim was to determine if women who regularly perform endurance exercise demonstrate age-related elevations in body mass and adiposity. Ninety-five healthy females were studied: premenopausal (n = 28; mean +/- SE age 30 +/- 1 yr) and postmenopausal (n = 31; 56 +/- 1 yr) endurance-trained runners and premenopausal (n = 17; 29 +/- 1 yr) and postmenopausal (n = 19; 61 +/- 1 yr) sedentary controls. In the runners, body mass did not differ across age, but percent fat and fat mass were higher (P < 0.05) in the postmenopausal women. The age-related difference in total body fat, however, was only approximately 50% as great (P < 0.01) as that observed in the sedentary controls due in part to smaller age-related differences in central (truncal) fat. The higher fat mass in the postmenopausal runners was modestly (inversely) related to both exercise volume (r = -0.44, P < 0.01) and maximal oxygen consumption (r = -0.41, P < 0.01). The present findings provide experimental support for the hypothesis that women who regularly engage in vigorous endurance exercise may not gain body weight, undergo only a modest increase in total body fat, and do not demonstrate a significant elevation in central adiposity with age.

The apurinic/apyrimidinic endonuclease (APE/ref-1) DNA repair enzyme is elevated in premalignant and malignant cervical cancer

The multifunctional mammalian apurinic/apyrimidinic (AP) endonuclease (APE) is responsible for the repair of AP sites in DNA. In addition, this enzyme has been shown to function as a redox factor facilitating the DNA-binding capability of JUN and FOS, HeLa AP-1, and numerous other transcription factors, including Myb, members of the CREB family and nuclear factor-kappa B. Although previously presumed to be ubiquitously expressed at comparable levels in all tissues and cell types, recent evidence has shown APE to vary significantly in its expression between tissues and even within tissues. To further characterize APE expression at various stages of cervical neoplasia, we investigated the levels of APE protein expression using immunohistochemistry in normal cervix, pre-invasive and invasive squamous lesions of the cervix, as well as in cervical cancer cell lines. We report here that the APE protein is predominantly expressed in the nuclei of cells from both primary tumors and cervical cell lines, but the level of APE protein is significantly and dramatically elevated in cervical cancer tissue. These results implicate the use of anti-APE antibodies as an effective reagent in the early detection of premalignant and malignant cancer of the cervix. These findings are suggestive that the increase of a DNA repair enzyme in cancerous cells may allow these cells to be refractive to chemotherapy.

Metabolism and disposition of the antifolate LY231514 in mice and dogs

The metabolism and disposition of LY231514 was studied in mice and dogs. LY231514 is a novel pyrrotopyrimidine-based multi-target antifolate (MTA) showing broad in vivo antitumor activity in mouse models and is currently in phase II human clinical trials. Doses (iv) of the compound showed high plasma levels, resulting in AUC values of 30-33 micrograms-hr/ml for mice and dogs after 20 and 7.5 mg/kg doses, respectively. The compound was eliminated rapidly. Half-life values for mice and dogs were about 7 and 2 hr, respectively. In vitro plasma binding measured 56% in mice, 46% in dogs, and 81% in humans. Fecal elimination was the major excretion pathway in mice after single iv doses of [14C]LY231514. Urine constituted the major route of excretion in dogs. Parent LY231514 accounted for the majority of urinary radiocarbon in mice (90%) and dogs (68%). Minor metabolites were found in urine, but the amounts were too small to isolate or identify. Based on an earlier observation that LY231514 photodegraded to produce reaction products having similar retention times as these minor urinary isolates, a photo-oxidation system was developed which in fact produced these metabolites. Subsequently, these photolytically-produced materials were used as standards to identify two novel in vivo metabolites formed by oxidation of the pyrrolo-pyrimidine ring system of LY231514. The oxidative transformations are similar to those observed for tryptophan and other indoles in that the pyrrole ring is oxidized to give an amide; further oxidation cleaves this ring, one ring carbon is lost, and a ketone is formed.