Platelet-melanoma cell interaction is mediated by the glycoprotein IIb- IIIa complex

A human malignant melanoma cell line (M3Dau) was observed by electron microscopy to interact directly with human platelets and induced platelet aggregation. Fab fragments of a monoclonal antibody MoAb (LYP18), directed against the platelet glycoprotein (GP) IIb-IIIa complex, inhibited platelet-melanoma interactions and platelet-platelet aggregation. M3Dau melanoma cells bind LYP 18 and synthesize IIb-IIIa- like GPs. When the melanoma cells were preincubated with LYP 18, tumor- platelet interaction did not occur, suggesting that the interaction may be mediated by the IIb-IIIa-like GPs present on the melanoma cell surface. Glanzmann's thrombasthenic platelets, lacking GPIIb and IIIa, did not interact with melanoma cells, indicating that the platelet GPIIb-IIIa complex is also necessary for the platelet-melanoma cell interaction. This work demonstrates the importance of the IIb-IIIa-like GPs, present on M3Dau melanoma cells, in mediating tumor-platelet interactions.     

Aurin tricarboxylic acid: a novel inhibitor of the association of von Willebrand factor and platelets

Shear stress activated platelets undergo aggregation in the presence of large or unusually large von Willebrand factor (vWF) multimers without the addition of ristocetin or any other exogenous chemical. This phenomenon may be analogous to the platelet aggregation that leads to thrombosis in the narrowed arteries and arterioles of patients with atherosclerosis or vasospasm. A triphenyl-methyl compound, aurin tricarboxylic acid (ATA), inhibits shear-induced, vWF-mediated platelet aggregation in platelet-rich plasma (PRP) in concentrations above 200 mumol/L and in buffer suspensions of washed platelets at a concentration of 0.1 mumol/L. In a concentration-dependent manner, ATA also inhibits ristocetin-induced, vWF-mediated platelet clumping in both fresh and formaldehyde-fixed platelet suspensions. This inhibition can be overcome by increasing the concentration of vWF, following the kinetics of first order competitive inhibition. ATA prevents the attachment to platelets of the largest vWF multimeric forms found in normal plasma and of the unusually large vWF multimers derived from endothelial cells. The rate of aggregation and degree of inhibition by ATA is not accounted for by the binding of ristocetin or calcium. Arachidonic acid- and adenosine diphosphate (ADP)-induced aggregation are not inhibited by ATA. Platelets incubated with ATA can be easily separated from the compound. However, ATA binds to large vWF multimeric forms and inhibits their ristocetin-induced interaction with platelet glycoprotein Ib. Because ATA also inhibits shear-induced, vWF-mediated platelet aggregation in vitro in the absence of ristocetin, it may be a useful prototype compound to impede the development of arterial thrombosis in vivo.     

p16 gene homozygous deletions in acute lymphoblastic leukemia

The p16 protein is a cyclin inhibitor encoded by a gene located in 9p21, which may have antioncogenic properties, and is inactivated by homozygous p16 gene deletion or, less often, point mutation in several types of solid tumors often associated to cytogenetic evidence of 9p21 deletion. We looked for homozygous deletion and point mutation of the p16 gene in acute lymphoblastic leukemia (ALL), where 9p21 deletion or rearrangement are also nonrandom cytogenetic findings. Other hematologic malignancies including acute myeloid leukemia (AML), myelodysplastic syndromes (MDS), chronic lymphocytic leukemia (CLL), and myeloma were also studied. Homozygous deletion of the p16 gene was seen in 9 of the 63 (14%) ALL analyzed, including 6/39 precursor B-ALL, 3/12 T-ALL, and 0/12 Burkitt's ALL. Three of the 7 ALL with 9p rearrangement (including 3 of the 5 patients where this rearrangement was clearly associated to 9p21 monosomy) had homozygous deletion compared to 5 of the 55 patients with normal 9p (the last patient with homozygous deletion was not successfully karyotyped). Single stranded conformation polymorphism analysis of exons 1 and 2 of the p16 gene was performed in 88 cases of ALL, including the 63 patients analyzed by Southern blot. Twenty-six of the cases had 9p rearrangement, associated to 9p21 monosomy in at least 12 cases. A missense point mutation, at codon 49 (nucleotide 164), was seen in only 1 of the 88 patients. No homozygous deletion and no point mutation of the p16 gene was seen in AML, MDS, CLL, and myeloma. Homozygous deletion of interferon alpha genes (situated close to p16 gene in 9p21) was seen in only 3 of the 9 ALL patients with p16 gene homozygous deletion, and none of the ALL without p16 gene homozygous deletion. Our findings suggest that homozygous deletion of the p16 gene is seen in about 15% of ALL cases, is not restricted to cases with cytogenetically detectable 9p deletion, and could have a pathogenetic role in this malignancy. On the other hand, p16 point mutations are very rare in ALL, and we found no p16 homozygous deletions or mutations in the other hematologic malignancies studied.     

Additive effect of erythropoietin and heme on murine hematopoietic recovery after azidothymidine treatment [see comments]

The ability of combination treatment with erythropoietin (Epo) and heme to rescue hematopoietic activity in mice from the suppressive effect of azidothymidine (AZT) was determined. Exposure of mice to AZT for 5 weeks produced marked anemia, thrombocytopenia, neutropenia, and weight loss, whereas mice that received Epo and heme for 3 subsequent weeks showed significant alleviation of AZT cytotoxicity. Treatment with Epo (10 U for 5 times/week) stimulated hematopoietic recovery in the AZT- treated animals and reduced the severe anemia and thrombocytopenia by 3 weeks. Administration of a lower Epo dose (1 U Epo) resulted in only a modest retardation of AZT-induced anemia, although, when combined with heme, there was a great improvement in recovery of erythropoiesis. The combination of heme with Epo (10 U) produced the optimum response, resulting in almost normal recovery of bone marrow cellularity as well as recovery of burst-forming units-erythroid (BFU-E) and splenic hematopoietic progenitor content (colony-forming unit-spleen [CFU-S]) by the end of 3 weeks of post-AZT treatment. Treatment with heme alone markedly enhanced the recovery of BFU-E and CFU-S, as well as body weight post-AZT; however, this recovery was not to the extent seen in combination with Epo (10 U). Long-term bone marrow cultures (LTBMCs) established from mice exposed to AZT for 8 weeks showed a marked reduction in cellularity and this was completely alleviated when mice received heme and Epo (10 U) for 3 weeks after 5 weeks of AZT administration. The additive effect of heme and Epo was seen in BFU-E production, as well as in CFU-S production, in LTBMCs. Thus, heme exerts a significant protective effect on hematopoietic progenitors in vivo and may be of potential clinical use in combination with Epo to promote effective erythropoiesis in the setting of AZT therapy.     

Predictive value for treatment outcome in acute myeloid leukemia of cellular daunorubicin accumulation and P-glycoprotein expression simultaneously determined by flow cytometry

To evaluate the clinical relevance of multidrug resistance (MDR) phenotype, the intracellular daunorubicin accumulation (IDA) and P- glycoprotein (P-gp) expression were investigated in 87 adult patients with acute leukemia: 69 patients with de novo acute myeloid leukemia (AML), 10 with AML at relapse, and eight with secondary leukemia to myelodysplastic syndromes (MDS-AML). IDA and P-gp expression were determined by double-labeling flow cytometry analysis. Of 87 patients, 36 expressed P-gp (41%). P-gp expression was more frequently observed in AML at relapse and MDS-AML as compared with de novo AML (P = .0001). P-gp expression was significantly associated with CD34 expression (P = .0003) and chromosome 7 abnormalities (P = .027). A significantly reduced IDA was observed in P-gp+ as compared with P-gp- patients (P = .0007). Of the 87 patients, 51 achieved complete remission (CR). A reduced IDA was observed in patients in failure as compared with patients in CR (22% +/- 17% v 42% +/- 21%; P = 10(-4). Twelve of 36 P- gp+ patients as compared with 40 of 51 P-gp- patients achieved CR (33% v 78%; P = 10(-4). The prognostic value of IDA and P-gp expression was confirmed in multivariate analysis. These data suggest that the determination of IDA and P-gp expression may be useful in designing therapy for patients with AML.     

Control of hypertension with medication: a comparative analysis of national surveys in 20 countries

Objective

To examine hypertension management across countries and over time using consistent and comparable methods.

Methods

A systematic search identified nationally representative health examination surveys from 20 countries containing data from 1980 to 2011 on blood pressure measurements, the diagnosis and treatment of hypertension and its control with antihypertensive drugs. For each country, the prevalence of hypertension (i.e. systolic blood pressure ≥ 140 mmHg or antihypertensive use) and the proportion of hypertensive individuals whose condition was diagnosed, treated or controlled with medications (i.e. systolic pressure < 140 mmHg) were estimated.

Findings

The age-standardized prevalence of hypertension varied between countries: for individuals aged 35 to 49 years, it ranged from around 12% in Bangladesh, Egypt and Thailand to around 30% in Armenia, Lesotho and Ukraine; for those aged 35 to 84 years, it ranged from 20% in Bangladesh to more than 40% in Germany, the Russian Federation and Turkey. The age-standardized percentage of hypertensive individuals whose condition was diagnosed, treated or controlled was highest in the United States of America: for those aged 35 to 49 years, it was 84%, 77% and 56%, respectively. Percentages were especially low in Albania, Armenia, the Islamic Republic of Iran and Turkey. Although recent trends in prevalence differed in England, Japan and the United States, treatment coverage and hypertension control improved over time, particularly in England.

Conclusion

Globally the proportion of hypertensive individuals whose condition is treated or controlled with medication remains low. Greater efforts are needed to improve hypertension control, which would reduce the burden of noncommunicable diseases.     

Continuous versus interrupted sutures for repair of episiotomy or second-degree perineal tears: a randomised controlled trial

Objective  To evaluate the repair techniques of continuous and interrupted methods for episiotomy or perineal tears.
Design  A randomised controlled trial.
Setting  The Hospital Universitario Principe de Asturias, a state hospital belonging to the community of Madrid.
Sample  Four hundred forty-five women who had undergone vaginal deliveries with episiotomies or second-grade tearing of the perineum between September 2005 and July 2007.
Methods  One group was repaired with continuous, nonlocking sutures involving the vagina, perineum, and subcutaneous tissues. The other group had continuous, locking sutures of the vagina, interrupted sutures in the perineal muscles, and interrupted transcutaneous sutures. The threads used for stitching were identical in both groups.
Main outcome measures  The participants were questioned regarding the sensation of pain and the use of painkillers on the second and the tenth days, and 3 months postpartum.
Results  When comparing the group with continuous suture to the group with interrupted sutures, the differences included less repair time (1 minute; P = 0.017) and less suture material used (relative risk [RR], 3.2, 95% CI: 2.6–4.0). The comparison of pain on the second and tenth days, and 3 months postpartum were not statistically different between the two techniques (RR, 1.08, 95% CI: 0.74–1.57; RR, 0.96, 95% CI: 0.59–1.55; and RR, 0.68, 95% CI: 0.19–2.46, respectively).
Conclusions  Although we did not demonstrate that one technique was better than the other in the incidence of pain in the short or long term, we showed that episiotomy and perineal tear repairs with continuous suturing were quicker and used less suture material without an increase in complication than interrupted suturing.     

北京市社区妇女人乳头瘤病毒感染率及其对HPV和疫苗认知情况的调查分析

[目的]评估北京市社区妇女人乳头瘤病毒（HPV）的感染率;调查社区人群对HPV的认知情况以及对HPV疫苗接种的态度。[方法]采用横断面调查方法,对北京市展览路社区15￣54岁女性进行HPV认知和流行病学问卷调查,并留取了宫颈脱落细胞或会阴部标本进行HPV DNA检测。[结果]1013名女性接受了问卷调查,832例HPV DNA检测结果纳入了统计学分析。HPV总检出率为15.38%,高、低危型HPV感染率分别为13.34%和3.25%,同时感染高、低危型HPV的检出率为1.20%。1013名调查对象中有30.7%听说过HPV,其中51.78%知道HPV感染与宫颈癌有关;HPV的知晓率与年龄和教育程度有关（P〈0.05）;经过简单宣教后,75.91%愿意接种HPV疫苗。[结论]北京市社区妇女HPV现患率较高,对HPV的知晓率也较高。开展公众健康教育,提高人群的认识水平是疫苗计划获得成功的关键因素。     

Immunity to hepatitis B, poliomyelitis and measles in fully vaccinated Aboriginal and Torres Strait Island children

Objective: To determine the immunity to hepatitis B, poliomyelitis and measles in fully vaccinated Aboriginal and Torres Strait Island children in north Queensland.
Methodology: A cross-sectional survey of immunity in a sample of children; 101 fully vaccinated Aboriginal and Torres Strait Island children, with a median age of 24.5 months, from 10 communities in North Queensland participated in this study. The main outcome measures were the prevalence of adequate antibody levels against hepatitis B, poliomyelitis and measles.
Results: Only 54% (95% Cl 44–63%) of the children had adequate immunity (10 m iu/mL) to hepatitis B, and one child had been infected despite vaccination. Although all the children (95% Cl 96–100%) had adequate immunity (i.e. neutralizing antibodies at a dilution of 1:8) to poliovirus 2, only 93% (95% Cl 86–96%) and 60% (95% Cl 50–69%) had adequate immunity to polioviruses 1 and 3, respectively. Nearly all (96%; 95% Cl 90–98%) of the children had adequate immunity (i.e. detectable IgG antibody) to measles.
Conclusions: Although a relatively low proportion of the children had adequate antibody levels against hepatitis B the clinical significance of this observation is uncertain. Further studies are needed to determine whether fully vaccinated Torres Strait Island children have been adequately protected and whether they require a booster dose of hepatitis B vaccine. A substantial proportion of fully vaccinated Aboriginal and Torres Strait Island children are inadequately protected against poliomyelitis, and therefore any such child with acute flaccid paralysis should be investigated fully for poliomyelitis. Vaccinated Aboriginal and Torres Strait Island children are well protected against measles, as are other Australian children.