However, abrupt tobacco abstinence precipitated by a hospital adm

However, abrupt tobacco abstinence precipitated by a hospital admission can provoke nicotine withdrawal symptoms (American Psychiatric Association, 2000). Clinical guidelines selleck bio recommend offering hospitalized smokers nicotine replacement therapy (NRT), which is effective in alleviating these symptoms (Fiore et al., 2008). NRT has been shown in clinical trials to be a safe and effective smoking cessation aid that increases the odds of long-term abstinence by 50%�C70% in outpatients when used for 8�C12 weeks (Stead, Perera, Bullen, Mant, & Lancaster, 2008). However, less than a third of smokers report having used NRT in their last quit attempt (Shiffman, Brockwell, Pillitteri, & Gitchell, 2008). The low rate of NRT use may be partly due to misapprehensions about NRT.

Endorsement of false beliefs about NRT, specifically that it is not safer than smoking, that it is addictive and that it is not effective are common and are associated with not having used the medication in the past and not planning to use it in future quit attempts (Shiffman, Ferguson, Rohay, & Gitchell, 2008). The practice of providing pharmacotherapy to hospitalized smokers may help correct common misunderstandings about NRT. When NRT is offered by hospital staff, patients are assured that the medication is not only safe but also safe for them, given their current health problem. If they accept the offer, they can experience firsthand its ability to reduce withdrawal symptoms and they may receive counseling that will give them greater confidence in the medication and their ability to use it properly.

As a result, those who use NRT in hospital may be encouraged to use NRT at home if they attempt to remain abstinent after discharge. To characterize the use of NRT during and after a hospitalization, we conducted an observational study of smokers who were admitted to a large hospital and routinely referred to its tobacco treatment service (TTS). Patients received counseling and medication recommendations while hospitalized and were followed for 2 weeks after discharge to assess NRT use. Our hypothesis was that the patients who used NRT in hospital would be more likely to initiate use after discharge in an attempt to quit smoking. Methods Setting and Participants This study was reviewed and approved by the Partners Healthcare System Institutional Review Board.

It was conducted at Massachusetts General Carfilzomib Hospital, a 900-bed teaching hospital in Boston, MA. Physicians in the medical, neurology, and surgical services admit inpatients using a computerized order entry system that prompts them to record smoking status and facilitates ordering of NRT at admission. Smokers identified this way are electronically referred to the TTS regardless of their interest in quitting smoking. Patients may also be referred by phone or fax at any time during hospitalization.

Precision-cut liver slice (PCLS) is a model that allows preservat

Precision-cut liver slice (PCLS) is a model that allows preservation of animal study the liver lobule architecture by maintaining cell diversity and interactions. PCLSs prepared from fasted mice were incubated with [14C]-palmitate to measure 14CO2 release during incubation. By this method, we found that the livers of DEF mice presented lower fatty acid oxidation compared to those of CT mice (Figure 2B). Incubation of PCLSs from fed CT and DEF mice with [14C]-acetate or [14C]-palmitate showed a 40% increase in TG synthesis and FA-esterification into TG in DEF mice compared to CT mice (Figure 2C, D). Figure 2 n-3 PUFA depletion leads to decreased hepatic fatty acid oxidation and increased TG secretion and synthesis.

Microarray analysis confirms a metabolic shift in favour of fatty acid and cholesterol synthesis at the expense of fatty acid oxidation in the livers of n-3 PUFA depleted mice The gene expression profiles in the livers of CT and DEF mice were analysed by microarray in both the fasted and fed state. Increased expression of all of the enzymes involved in fatty acid synthesis and desaturation was observed in DEF mice compared to CT mice in the fed and fasted states (Figure 3A and Table S2). The statistical significance of this observation was confirmed by analysing gene ontology with the bioinformatics tool DAVID (Table S3). DEF mice exhibited a lower expression of several markers of fatty acid oxidation, including PPAR�� and its target genes (Figure 3A and Table S2). The bioinformatics evaluation of transcription factor target genes among the list of genes regulated using TFactS [19] supported the inhibition of the PPAR�� pathway (Table S4).

Figure 3 n-3 PUFA-depleted mice exhibited higher mRNA content of enzymes involved in fatty acid and cholesterol synthesis. In agreement with the physiological data, phospholipid transfer protein (PLTP) and Apolipoprotein B (Apo B), two factors involved in fatty acid secretion, were increased in DEF mice when compared to CT mice (Table S2). Increased expression of several enzymes involved in cholesterol synthesis (from HMGCoAs to Dhcr7) and esterification for hepatic secretion (ACAT2) also occurred in fed and fasted DEF mice compared to CT mice (Figure 3B and Table S2). With regard to bile acid metabolism, a higher expression of Cyp7a1 and a lower expression of Cyp7b1 suggest a stimulation of the classic bile acid synthesis pathway AV-951 at the expense of the alternative pathway through n-3 PUFA depletion (Figure 3B and Table S2). SREBP-1c is involved in the metabolic alterations occurring in the livers of n-3 PUFA depleted mice TFactS analysis of microarray results revealed activation of SREBPs (Table S4) but did not distinguish between SREBP-2, SREBP-1c and SREBP-1a.

We next tested the specific

We next tested the specific Ponatinib order hypothesis that women would be more responsive to bupropion than to NRT. Finally, we examined group differences in specific characteristics that may be related to cessation outcome such as smoking heaviness, tobacco dependence, and cessation medication adherence (assessed using counts of unused medication that participants in the Efficacy trial returned). Results Participants Efficacy sample Of the 1,504 participants in the Efficacy trial, 58.2% were women. Among the 873 women, 132 (15.1%) self-identified as Black and 48 (5.4%) reported having less than a high school education. The majority of the Efficacy sample self-identified as White (83.9%); 204 (13.6%) self-identified as Black, and 38 (2.6%) self-identified as another race. Of those who self-identified as Black, 32 (15.

8%) reported less than a high school education. Approximately 2.8% of participants reported that one of their parents was of Hispanic origin. With respect to education, 84 (5.6%) participants reported having less than a high school education, 353 (23.5%) reported having a high school education/general educational development certificate (GED), and 1,058 (70.3%) reported having more than a high school education. In the Efficacy sample, participants had a mean age of 44.7 (SD = 11.1), smoked 21.4 cigarettes per day (SD = 8.9), and had made 5.7 previous quit attempts (SD = 9.7). There was only one significant correlation between gender, race, and education: White smokers tended to have higher educational attainment (r = ?.15, p < .001).

Effectiveness sample Of the 1,346 participants in the Effectiveness trial, 55.9% were women. Among the women, 81 (10.8%) self-identified as Black and 89 (11.8%) reported having less than a high school education. In the Effectiveness sample, the majority self-identified as White (87.0%), 128 (9.5%) self-identified as Black, and 43 (3.2%) self-identified as another race. Of those who self-identified as Black, 28 (21.8%) reported having less than a high school education. Hispanic ethnicity was reported by 29 (2.1%) participants. With respect to education, 172 (12.8%) participants reported having less than a high school education, 597 (44.4%) reported having a high school education/GED, and 577 (42.9%) reported having more than a high school education. In the Effectiveness sample, participants had a mean age of 44.

3 (SD = 12.1), smoked 20.3 cigarettes per day (SD = 8.8), and had made 5.7 previous quit attempts (SD = 9.3). Again there Cilengitide was a small but significant correlation (r = ?.07, p < .01) between education and race such that White smokers tended to have higher educational attainment. Sample differences Independent samples t test and chi-square analyses suggested that compared with smokers in the Effectiveness sample, smokers in the Efficacy sample smoked significantly more cigarettes per day (mean difference = 1.17; t (2822.29) = ?3.54, p < .


kinase inhibitor Paclitaxel Table 6. Logistic regression analyses of any exposure to secondhand smokea Discussion In our large sample of undergraduate students at 10 universities in North Carolina, we found high rates of self-reported SHS exposure. Some 83% of students reported any exposure in the 7 days preceding the survey. Exposure in a restaurant or bar was the most common (reported by 65% of students), followed by exposure at home or in the same room as a smoker (55%) and in a car (38%). A number of variables were found to be related significantly to either site-specific or any exposure to SHS. Daily smokers and nondaily smokers were more likely than nonsmokers to report exposure, which is not surprising given that they are more likely than other students to have friends who smoke and to frequent or live in locations where smoking occurs.

Similarly, students who binge drink were more likely than other students to report exposure, which is likely to reflect the co-occurrence of smoking and drinking among college students (McKee, Hinson, Rounsaville, & Petrelli, 2004; Sher, Gotham, Erickson, & Wood, 1996). Living in residence locations associated with smoking, such as Greek houses and off-campus housing, also was associated with self-reported exposure. Exposure patterns by age reflect the easier access that older students may have to drinking establishments. Individuals younger than 21 years were less likely than those of legal age to report exposure in a bar or restaurant; those aged 18�C20 years were more likely than those aged 21 years or older to report exposure in a car or at home.

A number of background characteristics were associated with exposure in one or more locations, including female gender, White race, and higher parental education levels. Characteristics of the larger school environment also were associated with the likelihood of exposure. The overall campus smoking rate was associated positively with reported exposure in a car, at home or in the same room, and in any location. Interestingly, attending a campus that was in the intervention condition of the SPARC trial, which focuses on policy, enforcement, and awareness changes to the campus and community environment to reduce high-risk drinking by students, was related negatively to reported exposure in bars and restaurants. Students Dacomitinib attending one of the two private universities were less likely to report exposure than were those at one of the eight public schools in the sample.

In addition, efforts that are able to successfully delay smoking

In addition, efforts that are able to successfully delay smoking initiation among sexual minorities may reduce disparities in youth cigarette smoking. Such efforts, if successful, also have the potential to reduce risk for other substance use and associated harmful repercussions as evidence suggests that nicotine exposure increases risk for other substance use (Levine et al., selleckchem 2011). Efforts to reduce sexual-orientation disparities in smoking should focus on identifying successful ways to assist these youth in adopting healthy strategies for coping with stress and to enhance social support from their family and friends. Funding The GUTS cohort has been funded by the Robert Wood Johnson Foundation; grants HD45763, DK46834, and HL03533 from the National Institutes of Health ; and grant RSGPB-04-009-01-CPPB from the American Cancer Society.

Dr. Corliss is supported by career development award DA23610 from the National Institute on Drug Abuse. Drs. Corliss and Austin are also supported by the Leadership Education in Adolescent Health Project, Maternal and Child Health Bureau, Health Resources and Services Administration grant 6T71-MC00009. Declaration of Interests None. Acknowledgments The authors would like to thank the participants of the Growing Up Today Study and the members of the Growing Up Today Study research team whose dedication made this study possible.
Smoking behavior is related to negative emotionality and behavioral undercontrol (e.g., Etter, 2010; Kahler et al., 2009; McCann, 2010).

Consistent with the personality findings describing the association between negative emotionality and smoking behavior, associations have been documented between cigarette smoking and negative affect (e.g., Anda et al., 1990; Bisol, Soldado, Albuquerque, Lorenzi, & Lara, 2010; Frederick, Frerichs, & Clark, 1988; Lyvers, Thorberg, Dobie, Huang, & Reginald, 2008). This literature indicates that smokers report greater depression, anxiety, anger, and stress relative to nonsmokers. Although the prevalence of adult cigarette smoking has decreased dramatically since 1965 to a low of 19.3% in 2010 (Centers for Disease Control and Prevention, 2011), some populations continue to have disturbingly high rates of smoking. Among treatment-seeking alcoholics, the rate of smoking is as high as 80% (see Kalman, Kim, DiGirolamo, Smelson, & Ziedonis, 2010). Understanding the characteristics and vulnerabilities of alcoholic smokers has important implications for alcohol treatment and nicotine cessation interventions. Despite the wealth of research examining associations of smoking behavior with personality and negative Cilengitide affect in the general population, it is unclear whether these relationships extend to alcoholics.

0 software (Chicago, IL, USA) A P-value of less than 0 05 was co

0 software (Chicago, IL, USA). A P-value of less than 0.05 was considered statistically significant. Results Cytotoxicity of evodiamine plus gemcitabine against SW1990 cells in vitro As shown by MTT assays (Fig. (Fig.2A),2A), treatment with evodiamine or gemcitabine alone reduced the cell viability by nearly 42% and 57%, respectively. Treatment sellckchem with combination of evodiamine and gemcitabine significantly reduced the cell viability by 80%. Further analysis by cell apoptosis assay indicated that single evodiamine increased the apoptotic rate from 12.6% to 28.6% and single gemcitabine increased the apoptotic rate from 12.6% to 34.2%, while treatment with evodiamine plus gemcitabine induced nearly 57.6% of cell apoptosis (Fig. (Fig.2B2B and C).

These data are consistent with results from cell growth inhibition studies using MTT, suggesting that the loss of viable cells by evodiamine and/or gemcitabine is partly due to the induction of cell apoptosis. Figure 2 Treatment with evodiamine plus gemcitabine inhibits the proliferation and induces apoptosis of SW1990 cells in vitro. SW1990 cells at 2��105/mL were cultured overnight in six-well plates and treated in triplicate with 20 ��mol/L of gemcitabine … Effect of evodiamine on the gemcitabine-induced NF-��B activity in vitro SW1990 cells were treated with 20 ��M of gemcitabine for varying periods and the DNA binding activity of NF-��B in the nuclear extracts was characterized by EMSA. As shown in Fig. Fig.3A,3A, SW1990 cells in the absence of gemcitabine displayed low levels of DNA binding activity, indicating low levels of spontaneous NF-��B activation.

Treatment of SW1990 cells with gemcitabine for 24 h increased the DNA binding activity of NF-��B by 436% in vitro, then activity of NF-��B gradually decreased to nearly a normal level at 72 h after treatment (Fig. (Fig.3A).3A). Treatment with different doses of evodiamine inhibited the DNA binding activity of NF-��B in SW1990 cells (Fig. (Fig.3B).3B). Batimastat More importantly, treatment with gemcitabine plus evodiamine significantly reduced the DNA binding of NF-��B, as compared with that of gemcitabine treatment or control cells (Fig. (Fig.3C).3C). Therefore, treatment with evodiamine effectively inhibited the gemcitabine-induced NF-��B activation in vitro, which may contribute to inducing more SW1990 cells apoptosis. Figure 3 Effect of evodiamine on the spontaneous and gemcitabine-induced NF-��B activation in vitro. (A) Gemcitabine (20 ��mol/L) induces NF-��B activation in SW1990 cells, as evidenced by EMSA supershift experiment. (B) Treatment with evodiamine …

57�C62 More recently, high throughput technologies have

57�C62 More recently, high throughput technologies have Tofacitinib baldness made major contributions to the study of self-antigen�Cantibody systems as serologic biomarkers in osteosarcoma.10,11 In this study, we have used a novel ELISA to evaluate the presence of circulating ANG�CIgM immune complexes in the peripheral blood sera of patients with osteosarcoma and healthy individuals, and also to evaluate the usefulness of ANG�CIgM detection for an early diagnosis of osteosarcoma. Materials and Methods Patients The study included 117 patients with newly diagnosed osteosarcoma in the Department of Bone Tumors of the National Institute of Rehabilitation, Mexico City, Mexico between January 2007 and September 2009; their mean age was 23.8 years (range: 4�C74 years), and 76 men and 41 women took part.

Tumor staging was based on radiography, computed tomography, operative findings and pathology reports in accordance with the Enneking Surgical Staging System. All patients had histopathologic confirmation of osteosarcoma according the WHO classification. The median follow-up time was 43 months (range: 24�C72 months). Individual patient records were traced where possible. The comparative group consisted of 117 patients with other tumors (osteocondroma, fibrous displasia, encondroma, condroblastoma, Ewing��s tumor, giant cell bone tumor, desmoplastic fibroma, chondromyxoid fibroma, simple bone cyst, aneurysmal bone cyst, Langerhans�� cell histiocytosis) matched for age (��5 years), gender and ethnicity in the Department of Bone Tumors of National Institute of Rehabilitation, Mexico City, Mexico.

Control subjects The general reference (normal) control samples consisted of 117 healthy individuals (75 men and 42 women with a mean age of 25.2 years; range: 5�C73 years) in the Blood Transfusion Service of the National Institute of Rehabilitation. The absence of disease was confirmed by physical examination, clinical history and routine laboratory tests. Blood sampling Seven milliliters of the peripheral venous blood was drawn into a serum separator tube (Vacutainer Systems, code 607213, Becton-Dickinson, USA). Blood was allowed to clot for 1 h at room temperature (RT). Sera was obtained after centrifugation at 3000 r.p.m. for 10 min at 4 ��C. All serum samples were stored in 300 ��L aliquots at ?80 ��C until analysis.

Peripheral venous blood samples were collected from cancer patients before or after surgery, and during antiangiogenic therapy. Reagents All reagents were of analytical grade and were obtained from Sigma�CAldrich Ltd, Poole, UK, unless otherwise indicated. Gel-filtration Serum samples from 117 patients with biopsy-proven osteosarcoma were grouped and subjected to gelfiltration AV-951 analysis. One hundred microliters of pooled sera were analyzed as previously described. The presence of ANG�CIgM and ANG in the fractions collected from the gel-filtration column every 30s were tested by ELISA.

(a) Schematic time line representation of two administrations of

(a) Schematic time line representation of two administrations of a first-generation … Two doses of AdCMVHSV1-tk were given i.v. 4 weeks apart to three macaques. Only two of the animals received immunosuppression. PET imaging was performed 2 days after each adenovirus administration. The liver of the three animals showed evidence of transgene expression following the first administration, but Vorinostat MK0683 only one of the immunosuppressed subjects showed a certain degree of reexpression upon the second administration (Figure 1b,c). To rule out residual transgene expression from the first dose of adenovirus, a PET study was performed 1 week before the second adenoviral administration. This is shown in Supplementary Figure S1a that summarizes the sequential PET measurements of transgene expression performed in these animals.

In the nonhuman primates, the two-drug regime reduced the titer of neutralizing antibodies by one log, but failed to abolish the humoral response (Figure 1d). One potential reason is that the depletion of B cells had not been complete as previously suggested by other authors.22 In this regard, we found that in the subject who attained HSV1-tk partial reexpression, CD20+ B-cells in peripheral blood samples were virtually undetectable (Figure 1e). In the other animals treated with the same immunosuppressive regimen, B-cell counts were lowered only about 2.5 times in comparison to the control macaque (Figure 1e). This difference could account for the different gene-transfer outcome.

Peripheral blood T-lymphocytes (both CD4 and CD8) proliferated avidly upon in vitro exposure to adenoviral capsids, 6 weeks after the first administration (Figure 1f,g). Clearly less marked, albeit detectable, proliferation was substantiated in the CD4 T-cell compartment of the animal with partial transgene reexpression, and it is likely that these T-lymphocytes were still providing sufficient help for antibody responses (Figure 1f,g). Of note, all the animals tolerated the treatments well with only moderate increases of serum liver enzymes (Supplementary Figure S1b). More intensive immunosuppression with Rituximab, FK506, antithymocyte immunoglobulin, MMF, and steroids permit repeated transfer of the HSV1-tk transgene The partial success obtained in our first study (Figure 1) suggest that B-22 and T-cell suppression is important for permitting adenoviral vector readministration, but that the two-drug regimen may not be sufficient.

1 Therefore, we pursued a more intensive immunosuppressive protocol. Accordingly, a more intense five-drug immunosuppression regime was tested in a new group of three animals. Antithymocyte immunoglobulin (ATG),19,27 mycophenolate mofetil (MMF),28 and steroids were added. The course of Rituximab27 was intensified with weekly doses between adenoviral administrations. Batimastat FK506 was given as in the first group of macaques (Figure 2a).

Natural habitats of Prevotella sp include the rumen and hindgut

Natural habitats of Prevotella sp. include the rumen and hindgut of cattle, sellckchem sheep, and humans, where they help break down protein [32] and carbohydrate [33]. However, some species of this genus are known to be opportunistic pathogens to humans [34]. Proteobacteria were the second predominant phylum in the pygmy loris gastrointestinal tract with Pseudomonadales as the primary contributor to the Proteobacteria populations, followed by Enterobacteriales and Burkholderiales. The major genus in the Proteobacteria phylum is Pseudomonas, which is consistent with previous 16S rRNA gene-based data [7]. Several microbes belonging to the genus of Pseudomonas have a very diverse metabolism, including the ability to degrade organic solvents such as toluene [35] and phenol [36], [37].

This ability may benefit the pygmy loris, given that they consume several toxic and pungent insects. Pseudomonas fluorescens was the predominant species among the Pseudomonas in the pygmy loris metagenome. P. fluorescens is a common Gram-negative bacterium that can be found in the low section of the human digestive tract [38]. Similarly, Clostridia and Bacilli are the primary contributors to the Firmicutes populations. However, various genera were found in the pygmy loris metagenome than in the 16S rRNA gene [7] (Table S2). Clostridiales is the dominant order in Clostridia, which includes well-known gut bacteria, Faecalibacterium prausnitzii. F. prausnitzii is the most important n-butyrate producing gut bacterium with well-known effects on host energy metabolism and mucosal integrity [39].

A distinctive feature of the pygmy loris metagenome is the abundance of phylum Verrucomicrobia, particularly the members of the genus Akkermansia; this abundance was unexpected and far greater than in humans (Table S2, Figure 2). The dominant species in the Verrucomicrobia phylum was Akkermansia muciniphila, which are common members of the human gut microbiota evident in human infants [40]. These mucin-degrading bacteria are related to normal mucosa development. Moreover, the Akkermansia species may have a role in maintaining intestinal integrity. Figure 2 Phylogenetic clustering of pygmy loris, human, mouse, canine, cow, and chicken gastrointestinal metagenomes. Eukaryota were a minor constituent (~4.0%) in the pygmy loris metagenome. Species of Blastocystis were also represented in small quantities (<0.

01%) in the pygmy loris metagenome. These species have been reported as the most commonly occurring micro-eukaryote in human feces [41], [42]. In addition, the presence of Blastocystis has been linked to a number of gut-related diseases. Some of these diseases could be the outcome of the predation of beneficial bacteria by Blastocystis in light of the similar observations in ruminant Carfilzomib cattle and their communalistic protozoa [43]. Fungi have very low abundance sequences (0.

6 C), consistent with a central role of the S1P�CS1pr1 pathway fo

6 C), consistent with a central role of the S1P�CS1pr1 pathway for PP fragmentation and release of kinase inhibitor Volasertib platelets. Short-term treatment with W146 also reduced platelet counts in CD1 mice (Fig. 6 D), suggesting that S1pr1 controls thrombopoiesis across different strains of mice. W146 maintains an adequate in vivo receptor blockade for only 5�C6 h (Sanna et al., 2006), and shedding reoccurred 6 h after a single dose of W146, suggesting that S1pr1 inhibition does not affect the viability of MKs (Fig. 6 A and Video 8). In rare instances, where PP shedding occurred in the presence of the S1pr1 inhibitor W146, the time required until an intravascular fragment dissociated from its MKs stem was significantly prolonged (Fig. 6 E). The failure to properly shed PPs resulted in the formation of abnormal, thick intravascular PP processes (Video 8).

In line with this observation, the few PP fragments that were released despite the presence of W146 were significantly bigger compared with those in vehicle-treated control mice (Fig. 6 F), reminiscent of the large platelets observed in S1pr1-null chimaeras (Fig. 6 G and Table S2). S1pr1 agonists enhance platelet production Modulation of S1P receptors by FTY720 (fingolimod) has become a promising strategy for the treatment of patients with multiple sclerosis (Kappos et al., 2006). Here, we show that treatment of mice with a single dose of FTY720 leads to a prompt and transient increase in circulating platelets (Fig. 7 A). When we used MP-IVM to examine MKs before and after treatment with a single dose of FTY720, we found that FTY720 accelerates the shedding of intravascular PP extensions into the blood stream.

As a consequence, the number of MKs carrying intravascular PPs significantly decreased immediately after a single dose of FTY720 compared with vehicle (Fig. 7, B and C). This suggests that FTY720 represents an agonist for megakaryocytic S1pr1 receptors and has the potential to rapidly mobilize PPs into the blood, most likely by supporting fragmentation of intravascular PPs (Fig. 7, B and C). Treatment with the S1pr1-specific agonist SEW2871 also caused an increase in circulating blood platelets (Fig. 7 D), further supporting that activation of S1P�CS1pr1 receptor signaling enhances thrombopoiesis. Figure 7. The S1P analogue FTY720 and SEW2871 trigger rapid release of platelets. (A) Mice were treated with a single dose of FTY720 (3 mg/kg i.

p.) or DMSO (vehicle). Open bars indicate baseline of platelet counts assessed before drug administration; closed bars … DISCUSSION Our results assign a new role for S1P and its receptor S1pr1 as master regulators of thrombopoiesis. Entinostat In a dose-dependent and sequential manner, S1P controls two key steps in the cascade of thrombopoiesis by BM MKs: (1) the polarized development of PP extensions into the blood stream and (2) the subsequent shedding of PPs from their transendothelial stems.