Vertically transmitted microbiome protects eggs from fungal infection and egg failure

Background

Beneficial microbes can be vertically transmitted from mother to offspring in many organisms. In oviparous animals, bacterial transfer to eggs may improve egg success by inhibiting fungal attachment and infection from pathogenic microbes in the nest environment. Vertical transfer of these egg-protective bacteria may be facilitated through behavioral mechanisms such as egg-tending, but many species do not provide parental care. Thus, an important mechanism of vertical transfer may be the passage of the egg through the maternal cloaca during oviposition itself. In this study, we examined how oviposition affects eggshell microbial communities, fungal attachment, hatch success, and offspring phenotype in the striped plateau lizard, Sceloporus virgatus, a species with no post-oviposition parental care.

Results

Relative to dissected eggs that did not pass through the cloaca, oviposited eggs had more bacteria and fewer fungal hyphae when examined with a scanning electron microscope. Using high throughput Illumina sequencing, we also found a difference in the bacterial communities of eggshells that did and did not pass through the cloaca, and the diversity of eggshell communities tended to correlate with maternal cloacal diversity only for oviposited eggs, and not for dissected eggs, indicating that vertical transmission of microbes is occurring. Further, we found that oviposited eggs had greater hatch success and led to larger offspring than those that were dissected.

Conclusions

Overall, our results indicate that female S. virgatus lizards transfer beneficial microbes from their cloaca onto their eggs during oviposition, and that these microbes reduce fungal colonization and infection of eggs during incubation and increase female fitness. Cloacal transfer of egg-protective bacteria may be common among oviparous species, and may be especially advantageous to species that lack parental care.

Supplementary Information

The online version contains supplementary material available at 10.1186/s42523-021-00104-5.

Hemispheric asymmetry in ocean change and the productivity of ecosystem sentinels

Climate change and other human activities are causing profound effects on marine ecosystem productivity. We show that the breeding success of seabirds is tracking hemispheric differences in ocean warming and human impacts, with the strongest effects on fish-eating, surface-foraging species in the north. Hemispheric asymmetry suggests the need for ocean management at hemispheric scales. For the north, tactical, climate-based recovery plans for forage fish resources are needed to recover seabird breeding productivity. In the south, lower-magnitude change in seabird productivity presents opportunities for strategic management approaches such as large marine protected areas to sustain food webs and maintain predator productivity. Global monitoring of seabird productivity enables the detection of ecosystem change in remote regions and contributes to our understanding of marine climate impacts on ecosystems.

Evaluation of Pirfenidone and Nintedanib in a Human Lung Model of Fibrogenesis

Introduction: Idiopathic pulmonary fibrosis (IPF) is a progressive, fatal lung disease with a poor prognosis and increasing incidence. Pirfenidone and nintedanib are the only approved treatments for IPF but have limited efficacy and their mechanisms of action are poorly understood. Here we have examined the effects of pirfenidone and nintedanib in a human model of lung fibrogenesis, and compared these with the putative anti-fibrotic compounds Lipoxin A4 (LXA4), and senicapoc, a K_Ca3.1 ion channel blocker. Methods: Early fibrosis was induced in cultured human lung parenchyma using TGFβ1 for 7 days, ± pirfenidone, nintedanib, or LXA4. Pro-fibrotic responses were examined by RT-PCR, immunohistochemistry and soluble collagen secretion. Results: Thirty six out of eighty four IPF and fibrosis-associated genes tested were significantly upregulated by TGFβ1 in human lung parenchyma with a ≥0.5 log2FC (n = 32). Nintedanib (n = 13) reduced the mRNA expression of 14 fibrosis-associated genes including MMPs (MMP1,-4,-13,-14), integrin α2, CXCR4 and PDGFB, but upregulated α-smooth muscle actin (αSMA). Pirfenidone only reduced mRNA expression for MMP3 and -13. Senicapoc (n = 11) previously attenuated the expression of 28 fibrosis-associated genes, including αSMA, several growth factors, collagen type III, and αV/β6 integrins. Pirfenidone and nintedanib significantly inhibited TGFβ1-induced fibroblast proliferation within the tissue, but unlike senicapoc, neither pirfenidone nor nintedanib prevented increases in tissue αSMA expression. LXA4 was ineffective. Conclusions: Pirfenidone and nintedanib demonstrate modest anti-fibrotic effects and provide a benchmark for anti-fibrotic activity of new drugs in human lung tissue. Based on these data, we predict that the K_Ca3.1 blocker senicapoc will show greater benefit than either of these licensed drugs in IPF.

Improved detection of acute parvovirus B19 infection by immunoglobulin M EIA in combination with a novel antigen EIA

BACKGROUND AND OBJECTIVES

Although parvovirus B19 is a significant blood product contaminant, few methods other than polymerase chain reaction (PCR) have been developed to detect the presence of the virus.

MATERIAL AND METHODS

A B19 antigen enzyme immunoassay (EIA) has been developed and the sensitivity of detection is ascertained using dilutions of the B19 capsid protein VP2 and 10-fold dilutions of B19 viraemic serum. Once the assay cut-off was established, a panel of viraemic donations (n = 70) was screened by the antigen EIA. The B19 immunoglobulin M (IgM) and IgG status of these specimens was also determined. During screening of blood donor units by quantitative PCR, 70 individuals were identified with levels of B19 DNA greater than 10(6) IU/ml at the time of blood donation.

RESULTS

The sensitivity of the B19 antigen EIA was estimated to be equivalent to between 10(8) and 10(9) IU/ml B19 DNA or 1-10 pg/ml of recombinant capsid protein. B19 detection was significantly enhanced when viraemic specimens were pretreated with a low pH proprietary reagent. Unlike other virus-detection assays, detection of the B19 antigen was not affected by the presence of B19 IgM or IgG antibodies. In addition, the assay was capable of detecting all three genotypes of human erythrovirus. Combined specimen analysis by the B19 antigen assay and a B19 IgM assay facilitated the detection of 91% of acute B19 infections in the test population.

CONCLUSION

In combination with B19 IgM detection, application of the B19 antigen EIA is a flexible and efficient method of detecting recent B19 infection and can be used as an alternative to PCR.

A new therapeutic approach to treat psoriasis by inhibition of fatty acid oxidation by Etomoxir

BACKGROUND

The dogma in psoriasis is that due to pathogen-induced inflammatory responses, an autoreactive immune response is induced that leads to tissue destruction. However, this model might be too simplistic. Literature data suggest that the expression of enzymes crucial for fatty acid oxidation is upregulated in the skin of patients with psoriasis compared with healthy individuals.

OBJECTIVES

To examine the influence of fatty acid oxidation on psoriasis with regard to expression and activity of the key enzyme in fatty acid oxidation, carnitine palmitoyltransferase-1 (CPT-1) and the effect of the CPT-1 inhibitor, Etomoxir.

METHODS

Experiments were performed with homogenates of lesional and healthy skin, fibroblast cultures and a model of human psoriatic skin transplanted on immune-deficient BNX mice.

RESULTS

CPT-1 was highly active in lesional skin. Etomoxir was able to block CPT-1 activity in skin, implying that this antagonist may have the potential to suppress psoriasis when administered topically. In the mouse model, Etomoxir had an antipsoriatic effect that was at least as good as that of betamethasone, as evidenced by reduction of epidermal thickness, keratinocyte proliferation and differentiation.

CONCLUSIONS

We conclude that fatty acid metabolism and in particular CPT-1 may be an excellent target for treatment of psoriasis.

Selection and interpretation of clinical pathology indicators of hepatic injury in preclinical studies

This position paper delineates the expert recommendations of the Regulatory Affairs Committee of the American Society for Veterinary Clinical Pathology for the use of preclinical, clinical pathology endpoints in assessment of the potential for drug-induced hepatic injury in animals and humans. Development of these guidelines has been based on current recommendations in the relevant preclinical and human clinical trial literature; they are intended to provide a method for consistent and rigorous interpretation of liver-specific data for the identification of hepatic injury in preclinical studies and potential liability for hepatic injury in human patients.

Screening the foods of an endangered parrot, the kakapo (Strigops habroptilus), for oestrogenic activity using a recombinant yeast bioassay

In recent years the possibility of environmental oestrogens affecting the reproduction of vertebrates has become an issue of both public and scientific interest. Although the significance of such chemicals remains controversial there is clear evidence that, in some contexts, environmental oestrogens can influence the fertility of vertebrates. Highly endangered species represent a situation in which even modest reductions in the fertility of key individuals may have implications for the survival of the entire species. This paper reports the screening of both natural and supplementary foods of the kakapo (Strigops habroptilus), a critically endangered New Zealand nocturnal parrot, for oestrogenic activity using a recombinant yeast based bioassay. Low levels of oestrogenic activity were detected in one of the 'chick-raising' foods, but no oestrogenic activity was detected in the adult supplementary foods. The oestrogenicity of a range of phytochemicals possibly associated with the kakapo natural diet was also examined. Two such phytochemicals, podocarpic acid and its reduced derivative podocarpinol, showed weak oestrogenic activity (approximately 10(-6) and 10(-4) of the activity of 17-beta-oestradiol, respectively).

Nuclear localization and shuttling of herpes simplex virus tegument protein VP13/14

The herpes simplex virus type 1 gene UL47 encodes the tegument proteins referred to collectively as VP13/14, which are believed to be differentially modified forms of the same protein. Here we show that the major product of the UL47 gene during transient expression is VP14, suggesting that some feature of virus infection is required to produce VP13. We have tagged VP13/14 with green fluorescent protein and have demonstrated that the protein is targeted efficiently to the nucleus, where it often localizes in numerous punctate domains. Furthermore, we show that removal of the N-terminal 127 residues of the protein abrogates nuclear accumulation, and we have identified a 14-amino-acid peptide from this region that is sufficient to function as a nuclear targeting signal and transport a heterologous protein to the nucleus. This short peptide contains two runs of four arginine residues, suggesting that the VP13/14 nuclear localization signal may behave in a manner similar to that of the arginine-rich nuclear localization signals of the retrovirus transactivator proteins Tat, Rev, and Rex. In addition, by using heterokaryon assays, we show that VP13/14 is capable of shuttling between the nucleus and cytoplasm of the cell, a property that may be attributed to three leucine-rich stretches in the C-terminal half of the protein that again bear similarity to the nuclear export signals of Rev and Rex. This is the first demonstration of a tegument protein that is specifically targeted to the nucleus, a feature which may be relevant both during virus entry, when VP13/14 enters the cell as a component of the tegument, and at later times, when large amounts of newly synthesized VP13/14 are present within the cell.

Fluorescent tagging of herpes simplex virus tegument protein VP13/14 in virus infection

The cellular site of herpesvirus tegument assembly has yet to be defined. We have previously used a recombinant herpes simplex virus type 1 expressing a green fluorescent protein (GFP)-tagged tegument protein, namely VP22, to show that VP22 is localized exclusively to the cytoplasm during infection. Here we have constructed a similar virus expressing another fluorescent tegument protein, YFP-VP13/14, and have visualized the intracellular localization of this second tegument protein in live infected cells. In contrast to VP22, VP13/14 is targeted predominantly to the nuclei of infected cells at both early and late times in infection. More specifically, YFP-13/14 localizes initially to the nuclear replication compartments and then progresses into intense punctate domains that appear at around 12 h postinfection. At even later times this intranuclear punctate fluorescence is gradually replaced by perinuclear micropunctate and membranous fluorescence. While the vast majority of YFP-13/14 seems to be targeted to the nucleus, a minor subpopulation also appears in a vesicular pattern in the cytoplasm that closely resembles the pattern previously observed for GFP-22. Moreover, at late times weak fluorescence appears at the cell periphery and in extracellular virus particles, confirming that YFP-13/14 is assembled into virions. This predominantly nuclear targeting of YFP-13/14 together with the cytoplasmic targeting of VP22 may imply that there are multiple sites of tegument protein incorporation along the virus maturation pathway. Thus, our YFP-13/14-expressing virus has revealed the complexity of the intracellular targeting of VP13/14 and provides a novel insight into the mechanism of tegument, and hence virus, assembly.

Findings from the NIMH Multimodal Treatment Study of ADHD (MTA): implications and applications for primary care providers

In 1992, the National Institute of Mental Health and 6 teams of investigators began a multisite clinical trial, the Multimodal Treatment of Attention-Deficit Hyperactivity Disorder (MTA) study. Five hundred seventy-nine children were randomly assigned to either routine community care (CC) or one of three study-delivered treatments, all lasting 14 months. The three MTA treatments-monthly medication management (usually methylphenidate) following weekly titration (MedMgt), intensive behavioral treatment (Beh), and the combination (Comb)-were designed to reflect known best practices within each treatment approach. Children were assessed at four time points in multiple outcome. Results indicated that Comb and MedMgt interventions were substantially superior to Beh and CC interventions for attention-deficit hyperactivity disorder symptoms. For other functioning domains (social skills, academics, parent-child relations, oppositional behavior, anxiety/depression), results suggested slight advantages of Comb over single treatments (MedMgt, Beh) and community care. High quality medication treatment characterized by careful yet adequate dosing, three times daily methylphenidate administration, monthly follow-up visits, and communication with schools conveyed substantial benefits to those children that received it. In contrast to the overall study findings that showed the largest benefits for high quality medication management (regardless of whether given in the MedMgt or Comb group), secondary analyses revealed that Comb had a significant incremental effect over MedMgt (with a small effect size for this comparison) when categorical indicators of excellent response and when composite outcome measures were used. In addition, children with parent-defined comorbid anxiety disorders, particularly those with overlapping disruptive disorder comorbidities, showed preferential benefits to the Beh and Comb interventions. Parental attitudes and disciplinary practices appeared to mediate improved response to the Beh and Comb interventions.

Parenting and family stress treatment outcomes in attention deficit hyperactivity disorder (ADHD): an empirical analysis in the MTA study

Parenting and family stress treatment outcomes in the MTA study were examined. Male and female (579), 7-9-year-old children with combined type Attention Deficit Hyperactivity Disorder (ADHD), were recruited at six sites around the United States and Canada, and randomly assigned to one of four groups: intensive, multi-faceted behavior therapy program alone (Beh); carefully titrated and monitored medication management strategy alone (MedMgt); a well-integrated combination of the two (Comb); or a community comparison group (CC). Treatment occurred over 14 months, and assessments were taken at baseline, 3, 9, and 14 months. Parenting behavior and family stress were assessed using parent-report and child-report inventories. Results showed that Beh alone, MedMgt alone, and Comb produced significantly greater decreases in a parent-rated measure of negative parenting, Negative/Ineffective Discipline, than did standard community treatment. The three MTA treatments did not differ significantly from each other on this domain. No differences were noted among the four groups on positive parenting or on family stress variables. Results are discussed in terms of the theoretical and empirically documented importance of negative parenting in the symptoms, comorbidities and long-term outcomes of ADHD.

Family processes and treatment outcome in the MTA: negative/ineffective parenting practices in relation to multimodal treatment

To elucidate processes underlying therapeutic change in a large-scale randomized clinical trial, we examined whether alterations in self-reported parenting practices were associated with the effects of behavioral, medication, or combination treatments on teacher-reported outcomes (disruptive behavior, social skills, internalizing symptoms) in children with attention-deficit hyperactivity disorder (ADHD). Participants were 579 children with Combined-type ADHD, aged 7-9.9 years, in the Multimodal Treatment Study of Children with ADHD (MTA). We uncovered 2 second-order factors of parenting practices, entitled Positive Involvement and Negative/Ineffective Discipline. Although Positive Involvement was not associated with amelioration of the school-based outcome measures, reductions in Negative/Ineffective Discipline mediated improvement in children's social skills at school. For families showing the greatest reductions in Negative/Ineffective Discipline, effects of combined medication plus behavioral treatment were pronounced in relation to regular community care. Furthermore, only in combination treatment (and not in behavioral treatment alone) was decreased Negative/Ineffective Discipline associated with reduction in children's disruptive behavior at school. Here, children in families receiving combination treatment who showed the greatest reductions in Negative/Ineffective Discipline had teacher-reported disruptive behavior that was essentially normalized. Overall, the success of combination treatment for important school-related outcomes appears related to reductions in negative and ineffective parenting practices at home; we discuss problems in interpreting the temporal sequencing of such process-outcome linkages and the means by which multimodal treatment may be mediated by psychosocial processes related to parenting.

Psychosocial treatment strategies in the MTA study: rationale, methods, and critical issues in design and implementation

The Collaborative Multimodal Treatment Study of Children with Attention Deficit Hyperactivity Disorder (ADHD), the MTA, is the first multisite, cooperative agreement treatment study of children, and the largest psychiatric/psychological treatment trial ever conducted by the National Institute of Mental Health. It examines the effectiveness of Medication vs. Psychosocial treatment vs. their combination for treatment of ADHD and compares these experimental arms to each other and to routine community care. In a parallel group design, 579 (male and female) ADHD children, aged 7-9 years, 11 months, were randomly assigned to one of the four experimental arms, and then received 14 months of prescribed treatment (or community care) with periodic reassessments. After delineating the theoretical and empirical rationales for Psychosocial treatment of ADHD, we describe the MTA's Psychosocial Treatment strategy applied to all children in two of the four experimental arms (Psychosocial treatment alone; Combined treatment). Psychosocial treatment consisted of three major components: a Parent Training component, a two-part School Intervention component, and a child treatment component anchored in an intensive Summer Treatment Program. Components were selected based on evidence of treatment efficacy and because they address comprehensive symptom targets, settings, comorbidities, and functional domains. We delineate key conceptual and logistical issues faced by clinical researchers in design and implementation of Psychosocial research with examples of how these issues were addressed in the MTA study.

Characterization of osteoclast precursors in human blood

Osteoclast precursors (OCPs) circulate in the mononuclear fraction of peripheral blood (PB), but their abundance and surface characteristics are unknown. Previous studies suggest that the receptor activator for NF-kappaB (RANK) on cytokine-treated OCPs in mouse bone marrow interacts with osteoprotegerin ligand (OPGL/TRANCE/RANKL/ODF) to initiate osteoclast differentiation. Hence, we used a fluorescent form of human OPGL (Hu-OPGL-F) to identify possible RANK-expressing OCPs in untreated peripheral blood mononuclear cells (PBMCs) using fluorescence-activated cell sorting analysis. Monocytes [CD14-phycoerythrin (PE) antibody (Ab) positive (+) cells, 10-15% of PBMCs] all (98-100%) co-labelled with Hu-OPGL-F (n > 18). T lymphocytes (CD3-PE Ab+ cells, 66% of PBMCs) did not bind Hu-OPGL-F; however, B cells (CD19-PE Ab+ cells, 9% of PBMCs) were also positive for Hu-OPGL-F. All Hu-OPGL-F+ monocytes also co-labelled with CD33, CD61, CD11b, CD38, CD45 and CD54 Abs, but not CD34 or CD56 Abs. Hu-OPGL-F binding was dose dependent and competed with excess Hu-OPGL. When Hu-OPGL-F+, CD14-PE Ab+, CD33-PE Ab+, Hu-OPGL-F+/CD14-PE Ab+ or Hu-OPGL-F+/CD33-PE Ab+ cells were cultured with OPGL (20 ng/ml) and colony-stimulating factor (CSF)-1 (25 ng/ml), OC-like cells readily developed. Thus, all freshly isolated monocytes demonstrate displaceable Hu-OPGL-F binding, suggesting the presence of RANK on OCPs in PB; also, OCPs within a purified PB monocyte population form osteoclast-like cells in the complete absence of other cell types in OPGL and CSF-1 containing medium.

Green fluorescent protein: A novel viability assay for cryobiological applications

Assessment of tissue viability following the application of a freezing protocol is challenging due to the paucity of viability assays that can be used dynamically, in situ. Cells transfected with a green fluorescent protein (GFP) vector actively produce GFP, which is retained intracellularly. Because of its constitutive and heritable expression, GFP fluorescence of transfected cells may have significant utility as a viability assay for cells within tissues. As a first step toward application to tissues, this work seeks to establish the validity of this GFP-based assay in cell suspensions by comparing the results to other accepted measures of viability. To the authors' knowledge, this is the first use of GFP in cryobiology applications. Intracellular GFP fluorescence was evaluated following slow freezing. Nontransfected and GFP-transfected rat 3230 adenocarcinoma (R3230AC) cells were frozen at 1 degrees C/min to minimum temperatures between -5 and -30 degrees C and then immediately thawed in a 37 degrees C water bath. Samples were assayed using the common viability indicators trypan blue and ethidium bromide (EtBr). A regression analysis of recovery measured with the GFP assay as a function of recovery measured with a trypan blue assay gave a correlation coefficient of 0.97. A similar correlation coefficient, 0.95, was determined for recovery assessed by the GFP assay as a function of recovery measured by an EtBr assay. Nontransfected and GFP-transfected cells responded similarly to slow freezing, indicating that GFP transfection did not significantly alter the response of cells to typical freezing conditions. The excellent correlation of GFP assay results with those of two common viability assays suggests that the GFP-based assay is valid for cells and that further development of a tissue viability assay based on transfection is appropriate.

Cytoplasm-to-nucleus translocation of a herpesvirus tegument protein during cell division

We have previously shown that the herpes simplex virus tegument protein VP22 localizes predominantly to the cytoplasm of expressing cells. We have also shown that VP22 has the unusual property of intercellular spread, which involves the movement of VP22 from the cytoplasm of these expressing cells into the nuclei of nonexpressing cells. Thus, VP22 can localize in two distinct subcellular patterns. By utilizing time-lapse confocal microscopy of live cells expressing a green fluorescent protein-tagged protein, we now report in detail the intracellular trafficking properties of VP22 in expressing cells, as opposed to the intercellular trafficking of VP22 between expressing and nonexpressing cells. Our results show that during interphase VP22 appears to be targeted exclusively to the cytoplasm of the expressing cell. However, at the early stages of mitosis VP22 translocates from the cytoplasm to the nucleus, where it immediately binds to the condensing cellular chromatin and remains bound there through all stages of mitosis and chromatin decondensation into the G(1) stage of the next cycle. Hence, in VP22-expressing cells the subcellular localization of the protein is regulated by the cell cycle such that initially cytoplasmic protein becomes nuclear during cell division, resulting in a gradual increase over time in the number of nuclear VP22-expressing cells. Importantly, we demonstrate that this process is a feature not only of VP22 expressed in isolation but also of VP22 expressed during virus infection. Thus, VP22 utilizes an unusual pathway for nuclear targeting in cells expressing the protein which differs from the nuclear targeting pathway used during intercellular trafficking.

Low-molecular-weight heparin vs heparin in the treatment of patients with pulmonary embolism. American-Canadian Thrombosis Study Group

BACKGROUND

Pulmonary embolism (PE) occurs in 50% or more of patients with proximal deep-vein thrombosis. Low-molecular-weight heparin treatment is effective and safe in patients with deep vein thrombosis and may also be so in patients with PE. Recent rigorous clinical trials have established objective criteria for determining a high probability of PE by perfusion lung scanning.

OBJECTIVE

To compare low-molecular-weight heparin with intravenous heparin for the treatment of patients with objectively documented PE and underlying proximal deep vein thrombosis.

METHODS

In a multicenter, double-blind, randomized trial, we compared fixed-dose subcutaneous low-molecular-weight heparin (tinzaparin sodium) given once daily with dose-adjusted intravenous heparin given by continuous infusion using objective documentation of clinical outcomes. Pulmonary embolism at study entry was documented by the presence of high-probability lung scan findings.

RESULTS

Of 200 patients with high-probability lung scan findings at study entry, none of the 97 who received low-molecular-weight heparin had new episodes of venous thromboembolism compared with 7 (6.8%) of 103 patients who received intravenous heparin (95% confidence interval for the difference, 1.9%-11.7%; P = .01). Major bleeding associated with initial therapy occurred in 1 patient (1.0%) who was given low-molecular-weight heparin and in 2 patients (1.9%) given intravenous heparin (95% confidence interval for the difference, -2.4% to 4.3%).

CONCLUSIONS

Low-molecular-weight heparin administered once daily subcutaneously was no less effective and probably more effective than use of dose-adjusted intravenous unfractionated heparin for preventing recurrent venous thromboembolism in patients with PE and associated proximal deep vein thrombosis. Our findings extend the use of low-molecular-weight heparin without anticoagulant monitoring to patients with submassive PE.

High volume medical web sites

In 1998, 22 million individuals reported surfing the web for medical information, and this number will increase to over 30 million by 2000. Fifteen of the highest volume medical web sites are described in this paper. Sponsorship and/or ownership of the fifteen sites varied. The government sponsors one, and some are the products of well-known educational institutions. One site is supported by a consumer health organization, and the American Medical Association was in the top 15. However, the most common owners are commercial, for-profit businesses. Attributes of the ideal site were categorized, and include a robust privacy and disclosure statement with an emphasis on education and an appropriate role for advertising. The covering of Complementary and Alternative Medicine (CAM) should be in a balanced and unbiased manner. There has to be an emphasis on knowledge based evidence as opposed to testimonials, and sources should be timely and reviewed. Bibliographies of authors need to be available. Hyperlinking to other web resources is valuable, as even the largest of sites cannot come close to covering all of medicine.

Evaluation of VP22 spread in tissue culture

We compare methods of detection of intercellular transport of the herpes simplex virus protein VP22 and of a green fluorescent protein (GFP)-VP22 fusion protein. Spread of both proteins was observed by immunofluorescence (IF) using organic fixatives. Spread of both proteins was also detected by IF after paraformaldehyde (PFA) fixation and detergent permeabilization, albeit at reduced levels. However, while spread of GFP-VP22 was observed by examining intrinsic GFP fluorescence after methanol fixation, little spread was observed after PFA fixation, suggesting that the levels of the fusion protein in recipient cells were below the detection limits of intrinsic-fluorescence or that PFA fixation quenches the fluorescence of GFP-VP22. We further considered whether elution of VP22 from methanol-fixed cells and postfixation binding to surrounding cells contributed to the increased detection of spread observed after methanol fixation. The results show that while this could occur, it appeared to be a minor effect not accounting for the observed VP22 cell-to-cell spread in culture.

Novel neurotrophin-1/B cell-stimulating factor-3: a cytokine of the IL-6 family

We have identified a cytokine of the IL-6 family and named it novel neurotrophin-1/B cell-stimulating factor-3 (NNT-1/BSF-3). NNT-1/BSF-3 cDNA was cloned from activated Jurkat human T cell lymphoma cells. Its sequence predicts a 225-aa protein with a 27-aa signal peptide, a molecular mass of 22 kDa in mature form, and the highest homology to cardiotrophin-1 and ciliary neurotrophic factor. The gene for NNT-1/BSF-3 is on chromosome 11q13. A murine equivalent to NNT-1/BSF-3 also was identified, which shows 96% homology to human NNT-1/BSF-3. NNT-1/BSF-3 mRNA is found mainly in lymph nodes and spleen. NNT-1/BSF-3 induces tyrosine phosphorylation of glycoprotein 130 (gp130), leukemia inhibitory factor receptor beta, and signal transducer and activator of transcription 3 in the SK-N-MC human neuroblastoma cells. NNT-1/BSF-3 shows activities typical of IL-6 family members. In vitro, it supports the survival of chicken embryo motor and sympathetic neurons. In mice, it induces serum amyloid A, potentiates the induction by IL-1 of corticosterone and IL-6, and causes body weight loss and B cell hyperplasia with serum IgG and IgM increase. NNT-1/BSF-3 is a gp130 activator with B-cell stimulating capability.

Thrombolytic therapy for venous thromboembolism

The role of thrombolytic therapy for venous thromboembolism remains uncertain. To date, no well-designed randomized clinical trial has shown that the benefits of thrombolysis exceed the risks for a well-defined subgroup of patients with acute pulmonary embolism. Recent reports have underscored the risks of thrombolytic therapy. The largest multinational registry of patients in whom acute pulmonary embolism had been diagnosed found that 3% of 311 patients who underwent thrombolysis for acute pulmonary embolism suffered an intracranial hemorrhage. Because of the serious risk associated with systemic thrombolysis, investigators have continued to study methods that rapidly remove venous thromboemboli while minimizing the risk. Reports of catheter fragmentation combined with thrombolysis as well as catheter-directed thrombolysis are promising, but well-designed clinical trials are needed to clarify the utility of these techniques.

Identification of phosphorylation sites within the herpes simplex virus tegument protein VP22

The herpes simplex virus protein VP22 is a major phosphoprotein of infected cells. In this study, we identify two serine phosphorylation sites within VP22 and show that the N-terminal site is a substrate for casein kinase II, while the extreme C-terminal site is a substrate for another, as yet unidentified, cellular kinase. Furthermore, we show that a mutant of VP22 which has both sites altered is unable to incorporate phosphate in vivo, confirming that there are no other phosphorylation sites within VP22.

Live-cell analysis of a green fluorescent protein-tagged herpes simplex virus infection

Many stages of the herpes simplex virus maturation pathway have not yet been defined. In particular, little is known about the assembly of the virion tegument compartment and its subsequent incorporation into maturing virus particles. Here we describe the construction of a herpes simplex virus type 1 (HSV-1) recombinant in which we have replaced the gene encoding a major tegument protein, VP22, with a gene expressing a green fluorescent protein (GFP)-VP22 fusion protein (GFP-22). We show that this virus has growth properties identical to those of the parental virus and that newly synthesized GFP-22 is detectable in live cells as early as 3 h postinfection. Moreover, we show that GFP-22 is incorporated into the HSV-1 virion as efficiently as VP22, resulting in particles which are visible by fluorescence microscopy. Consequently, we have used time lapse confocal microscopy to monitor GFP-22 in live-cell infection, and we present time lapse animations of GFP-22 localization throughout the virus life cycle. These animations demonstrate that GFP-22 is present in a diffuse cytoplasmic location when it is initially expressed but evolves into particulate material which travels through an exclusively cytoplasmic pathway to the cell periphery. In this way, we have for the first time visualized the trafficking of a herpesvirus structural component within live, infected cells.

Medical text books on the World Wide Web

The availability of medical textbooks for physicians on the web is rapidly increasing. Internet sites that maintain a listing of such resources are briefly described, and descriptions of particularly valuable fee based and free medical textbooks web sites are categorized.

Tumor necrosis factor receptor family member RANK mediates osteoclast differentiation and activation induced by osteoprotegerin ligand

A receptor that mediates osteoprotegerin ligand (OPGL)-induced osteoclast differentiation and activation has been identified via genomic analysis of a primary osteoclast precursor cell cDNA library and is identical to the tumor necrosis factor receptor (TNFR) family member RANK. The RANK mRNA was highly expressed by isolated bone marrow-derived osteoclast progenitors and by mature osteoclasts in vivo. Recombinant OPGL binds specifically to RANK expressed by transfected cell lines and purified osteoclast progenitors. Transgenic mice expressing a soluble RANK-Fc fusion protein have severe osteopetrosis because of a reduction in osteoclasts, similar to OPG transgenic mice. Recombinant RANK-Fc binds with high affinity to OPGL in vitro and blocks osteoclast differentiation and activation in vitro and in vivo. Furthermore, polyclonal Ab against the RANK extracellular domain promotes osteoclastogenesis in bone marrow cultures suggesting that RANK activation mediates the effects of OPGL on the osteoclast pathway. These data indicate that OPGL-induced osteoclastogenesis is directly mediated through RANK on osteoclast precursor cells.

Inflammatory cytokines and vascular endothelial growth factor stimulate the release of soluble tie receptor from human endothelial cells via metalloprotease activation

Activation of endothelial cells, important in processes such as angiogenesis, is regulated by cell surface receptors, including those in the tyrosine kinase (RTK) family. Receptor activity, in turn, can be modulated by phosphorylation, turnover, or proteolytic release of a soluble extracellular domain. Previously, we demonstrated that release of soluble tie-1 receptor from endothelial cells by phorbol myristate acetate (PMA) is mediated through protein kinase C and a Ca2+-dependent protease. In this study, the release of soluble tie-1 was shown to be stimulated by inflammatory cytokines and vascular endothelial growth factor (VEGF), but not by growth factors such as basic fibroblast growth factor (bFGF) or transforming growth factor alpha (TGFalpha). Release of soluble tie by tumor necrosis factor alpha (TNFalpha) or VEGF occurred within 10 minutes of stimulation and reached maximal levels within 60 minutes. Specificity was shown by fluorescence-activated cell sorting (FACS) analysis; endothelial cells exhibited a significant decrease in cell surface tie-1 expression in response to TNF, whereas expression of epidermal growth factor receptor (EGF-R) and CD31 was stable. In contrast, tie-1 expression on megakaryoblastic UT-7 cells was unaffected by PMA or TNFalpha. Sequence analysis of the cleaved receptor indicated that tie-1 was proteolyzed at the E749/S750 peptide bond in the proximal transmembrane domain. Moreover, the hydroxamic acid derivative BB-24 demonstrated dose-dependent inhibition of cytokine-, PMA-, and VEGF-stimulated shedding, suggesting that the tie-1 protease was a metalloprotease. Protease activity in a tie-1 peptide cleavage assay was (1) associated with endothelial cell membranes, (2) specifically activated in TNFalpha-treated cells, and (3) inhibited by BB-24. Additionally, proliferation of endothelial cells in response to VEGF, but not bFGF, was inhibited by BB-24, suggesting that the release of soluble tie-1 receptor plays a role in VEGF-mediated proliferation. This study demonstrated that the release of soluble tie-1 from endothelial cells is stimulated by inflammatory cytokines and VEGF through the activation of an endothelial membrane-associated metalloprotease.

Intercellular trafficking of VP22-GFP fusion proteins

The herpes simplex virus protein VP22 exhibits the unusual property of intercellular transport whereby after being synthesised in a subpopulation of cells, in which it is largely cytoplasmic, the protein is transported to adjacent cells where it accumulates mainly in the nucleus. Here we examine the transport of a fusion protein consisting of VP22 linked to the green fluorescent protein (GFP). Intercellular transport, nuclear accumulation and chromatin binding of VP22-GFP could be detected by intrinsic GFP fluorescence in fixed cells. However, while the cytoplasmic localisation of VP22-GFP could be detected in live cells actively synthesising the protein, we were unable to detect intercellular transport by intrinsic GFP fluorescence in livecells, indicating that the levels of transported protein may be below those required for live detection, or that GFP fluorescence was quenched. The use of antibody to GFP was more sensitive than intrinsic GFP fluorescence and allowed ready detection of transport and nuclear accumulation of VP22-GFP. Intercellular transport was also confirmed in coplating experiments. Consistent with previous results showing a requirement for the C-terminus of VP22 in transport of the native protein, a fusion protein consisting of GFP linked to the N-terminal 1-192 residues of VP22 failed to transport between cells. The results support the proposal that VP22 has the ability to transport cargo proteins between cells and that it has significant potential in the field of gene therapy.

Intercellular delivery of thymidine kinase prodrug activating enzyme by the herpes simplex virus protein, VP22

We demonstrate that fusion proteins consisting of the herpes simplex virus (HSV) transport protein VP22 linked in frame to HSV thymidine kinase (tk) retain the ability to be transported between cells. In vivo radiolabelling experiments and in vitro assays show that the fusion proteins also retain tk activity. When transfected COS cells, acting as a source of the VP22-tk chimera, were co-plated on to gap junction-negative neuroblastoma cells, ganciclovir treatment induced efficient cell death in the recipient neuroblastoma cell monolayer. No such effect was observed with COS cells transfected with tk alone. Tumours established in mice with neuroblastoma cell lines expressing VP22-tk regressed upon administration of ganciclovir. Furthermore tumours established from 50:50 mixtures of VP22-tk transduced and nontransduced cells also regressed while no significant effect was observed in similar experiments with cells transduced with tk alone. VP22 mediated transport may thus have application in a clinical setting to amplify delivery of the target protein in enzyme-prodrug protocols.

Complementary or Alternative medicine and the Internet

Complementary or Alternative Medicine (CAM) is being used with increasing frequency in the United States. This paper describes what CAM is, and catalogues mainstream medical Web sites. These online resources contain extensive information on CAM, and will provide a means to stay current with this sometimes-new yet often ancient area of medicine.

Herpes simplex virus type 1 tegument protein VP22 induces the stabilization and hyperacetylation of microtubules

The role of the herpes simplex virus type 1 tegument protein VP22 during infection is as yet undefined. We have previously shown that VP22 has the unusual property of efficient intercellular transport, such that the protein spreads from single expressing cells into large numbers of surrounding cells. We also noted that in cells expressing VP22 by transient transfection, the protein localizes in a distinctive cytoplasmic filamentous pattern. Here we show that this pattern represents a colocalization between VP22 and cellular microtubules. Moreover, we show that VP22 reorganizes microtubules into thick bundles which are easily distinguishable from nonbundled microtubules. These bundles are highly resistant to microtubule-depolymerizing agents such as nocodazole and incubation at 4 degreesC, suggesting that VP22 has the capacity to stabilize the microtubule network. In addition, we show that the microtubules contained in these bundles are modified by acetylation, a marker for microtubule stability. Analysis of infected cells by both immunofluorescence and measurement of microtubule acetylation further showed that colocalization between VP22 and microtubules, and induction of microtubule acetylation, also occurs during infection. Taken together, these results suggest that VP22 exhibits the properties of a classical microtubule-associated protein (MAP) during both transfection and infection. This is the first demonstration of a MAP encoded by an animal virus.

Full text core medical journals on the Internet

Peer reviewed, core medical journals have an increasing presence on the Internet. A significant number of them offer full text articles without fees. This paper indexes these resources, and discusses ways to keep the list current.

Intercellular delivery of functional p53 by the herpesvirus protein VP22

The herpes simplex virus type 1 (HSV-1) virion protein VP22 exhibits the remarkable property of intercellular trafficking whereby the protein spreads from the cell in which it is synthesized to many surrounding cells. In addition to having implications for protein trafficking mechanisms, this function of VP22 might be exploited to overcome a major hurdle in gene therapy, i.e., efficient delivery of genes and gene products. We show that chimeric polypeptides, consisting of VP22 linked to the entire p53 protein, retain their ability to spread between cells and accumulate in recipient cell nuclei. Furthermore the p53-VP22 chimeric protein efficiently induces apoptosis in p53 negative human osteosarcoma cells resulting in a widespread cytotoxic effect. The intercellular delivery of functional p53-VP22 fusion protein is likely to prove beneficial in therapeutic strategies based on restoration of p53 function. These results, demonstrating intracellular transport of large functional proteins, indicate that VP22 delivery may have applications in gene therapy.

Osteoprotegerin ligand is a cytokine that regulates osteoclast differentiation and activation

The ligand for osteoprotegerin has been identified, and it is a TNF-related cytokine that replaces the requirement for stromal cells, vitamin D3, and glucocorticoids in the coculture model of in vitro osteoclastogenesis. OPG ligand (OPGL) binds to a unique hematopoeitic progenitor cell that is committed to the osteoclast lineage and stimulates the rapid induction of genes that typify osteoclast development. OPGL directly activates isolated mature osteoclasts in vitro, and short-term administration into normal adult mice results in osteoclast activation associated with systemic hypercalcemia. These data suggest that OPGL is an osteoclast differentiation and activation factor. The effects of OPGL are blocked in vitro and in vivo by OPG, suggesting that OPGL and OPG are key extracellular regulators of osteoclast development.

Natural killer and B-lymphoid potential in CD34+ cells derived from embryonic stem cells differentiated in the presence of vascular endothelial growth factor

Differentiation of totipotent mouse embryonic stem (ES) cells to various lymphohematopoietic cells is an in vitro model of the hematopoietic cell development during embryogenesis. To understand this process at cellular levels, differentiation intermediates were investigated. ES cells generated progeny expressing CD34, which was significantly enhanced by vascular endothelial growth factor (VEGF). The isolated CD34+ cells were enriched for myeloid colony-forming cells but not significantly for erythroid colony-forming cells. When cultured on OP9 stroma cells in the presence of interleukin-2 and interleukin-7, the CD34+ cells developed two types of B220+ CD34- lymphocytes: CD3- cytotoxic lymphocytes and CD19+ pre-B cells, and such lymphoid potential was highly enriched in the CD34+ population. Interestingly, the cytotoxic cells expressed the natural killer (NK) cell markers, such as NKR-P1, perforin, and granzymes, classified into two types, one of which showed target specificity of NK cells. Thus, ES cells have potential to generate NK-type cytotoxic lymphocytes in vitro in addition to erythro-myeloid cells and pre-B cells, and both myeloid and lymphoid cells seem to be derived from the CD34+ intermediate, on which VEGF may play an important role.

Useful sites on the Internet

Internet medical sites offer the physician opportunities to improve patient care, to obtain continuing education and medical management services, and the ability to communicate with colleagues. This paper discusses how to choose the best sites, and highlights some valuable federal, university and commercial medical sites found on the Internet.

Examination of determinants for intranuclear localization and transactivation within the RING finger of herpes simplex virus type 1 IE110k protein

The herpesvirus regulatory protein IE110k possesses a cysteine-rich, RING finger motif required for its role in transactivation and virus replication. IE110k also localizes to subnuclear compartments termed PODs (PML oncogenic domains). Localization to PODs induces redistribution of the proteins associated with this nuclear compartment, including the cellular RING finger protein, PML. Here we construct a series of deletions, RING domain swaps and point mutations to analyse specific requirements within the IE110k RING finger for subnuclear localization, redistribution of PML and transactivation and we examine the relationship between these activities. We find that IE110k localizes to distinct nuclear subdomains that are more numerous than the cellular PODs and that mutation of two residues within a predicted loop of the RING finger, or replacing the IE110k RING finger with a RING finger from a cellular gene abrogates the ability of IE110k to localize to these extra compartments and traps IE110k in the original PODs. We further demonstrate that RING fingers from the cellular genes mdm-2 and Bmi I, when placed within IE110k, alter the nuclear distribution of IE110k, do not transactivate, and do not redistribute PML. We also demonstrate that the majority of wild-type IE110k, like PML, is associated with the nuclear matrix. Although substitutions and deletions within the RING finger abolish transactivation, these mutant proteins remain tightly associated with the matrix. These results further dissect the determinants involved in different aspects of nuclear compartmentalization of IE110k and are discussed in relation to PML, PODs and the IE110k RING finger.

National Institute of Mental Health Collaborative Multimodal Treatment Study of Children with ADHD (the MTA). Design challenges and choices

The Collaborative Multimodal Treatment Study of Children with Attention Deficit Hyperactivity Disorder (ADHD), the MTA, is the first child multisite cooperative agreement treatment study of children conducted by the National Institute of Mental Health, Rockville, Md. It examines the long-term effectiveness of medication vs behavioral treatment vs both for treatment of ADHD and compares state-of-the-art treatment with routine community care. In a parallel-groups design, 576 children (age, 7-9 years) with ADHD (96 at each site) are thoroughly assessed and randomized to 4 conditions: (1) medication alone, (2) psychosocial treatment alone, (3) the combination of both, (4) or community comparison. The first 3 groups are treated for 14 months and all are reassessed periodically for 24 months. Designers met the following challenges: framing clinically relevant primary questions; defining the target population; choice, intensity, and integration and combination of treatments for fair comparisons; combining scientific controls and standardization with clinical flexibility; and implementing a controlled clinical trial in a nonclinical setting (school) controlled by others. Innovative solutions included extensive decision algorithms and manualized adaptations of treatments to specific needs.

Regulation of tie receptor expression on human endothelial cells by protein kinase C-mediated release of soluble tie

The expression and activity of receptor tyrosine kinases (RTK) at the cell surface can be modulated by several different pathways including the proteolytic release of the extracellular domain as a soluble receptor. We investigated the regulation of tie receptor expression, an orphan RTK restricted to cells of hematopoietic and endothelial lineages, on primary human endothelial cells and a stably transfected Chinese hamster ovary (CHO) cell line. Tie was expressed in cells as a doublet of 135 and 125 kD; the 135-kD band represented mature cell surface receptor containing sialic acid and N-linked oligosaccharide residues, whereas the 125-kD band represented an intracellular pool of immature receptor. Phorbol 12-myristate 13-acetate (PMA) had dramatic effects on tie expression at the cell surface. Within 15 minutes of PMA treatment, the 135-kD band disappeared from the cell surface and was accompanied by the appearance of a 100-kD band in cell supernatants. The 100-kD band continued to accumulate in the media throughout the duration of PMA treatment during which mature tie receptor was undetectable on the cell surface by fluorescence-activated cell sorting (FACS) or in cell lysates by immunoblot analysis. Using specific antibodies, this 100-kD species was shown to be a soluble form of the tie receptor containing the extracellular domain. PMA-dependent release of soluble tie was mediated through the activation of protein kinase C (PKC); soluble tie was not released in the presence of PKC inhibitors, an inactive PMA analog, or following the downregulation of PKC through chronic PMA treatment. These results indicate that tie receptor expression on endothelial cells is regulated by the release of a soluble extracellular fragment following activation of PKC. Parallel pathways regulating c-kit, tumor necrosis factor (TNF), and colony-stimulating factor (CSF) receptor expression suggest that the release of extracellular receptor fragments represents an alternative mechanism through which cells modulate responses to growth factors and cytokines.