Novel assay demonstrates that coronary artery disease patients have heightened procoagulant platelet response

Essentials Procoagulant platelets can be detected using GSAO in human whole blood. Stable coronary artery disease is associated with a heightened procoagulant platelet response. Agonist-induced procoagulant platelet response is not inhibited by aspirin alone. Collagen plus thrombin induced procoagulant platelet response is partially resistant to clopidogrel.

SUMMARY

Background Procoagulant platelets are a subset of highly activated platelets with a critical role in thrombin generation. Evaluation of their clinical utility in thrombotic disorders, such as coronary artery disease (CAD), has been thwarted by the lack of a sensitive and specific whole blood assay. Objectives We developed a novel assay, utilizing the cell death marker, GSAO [(4-(N-(S-glutathionylacetyl)amino)phenylarsonous acid], and the platelet activation marker, P-selectin, to identify procoagulant platelets in whole blood by flow cytometry. Patients/Methods Using this assay, we characterized the procoagulant platelet population in healthy controls and a cohort of patients undergoing elective coronary angiography. Results In patients with CAD, compared with patients without CAD, there was a heightened procoagulant platelet response to thrombin (25.2% vs. 12.2%), adenosine diphosphate (ADP) (7.8% vs. 2.7%) and thrombin plus collagen (27.2% vs. 18.3%). The heightened procoagulant platelet potential in CAD patients was not associated with other markers of platelet function, including aggregation, dense granule release and activation of α2b β3 integrin. Although dual antiplatelet therapy (DAPT) was associated with partial suppression of procoagulant platelets, this inhibitory effect on a patient level could not be predicted by aggregation response to ADP and was not fully suppressed by clopidogrel. Conclusions We report for the first time that procoagulant platelets can be efficiently detected in a few microliters of whole blood using the cell death marker, GSAO, and the platelet activation marker, P-selectin. A heightened procoagulant platelet response may provide insight into the thrombotic risk of CAD and help identify a novel target for antiplatelet therapies in CAD.

Palmitoylation of cdc42 Promotes Spine Stabilization and Rescues Spine Density Deficit in a Mouse Model of 22q11.2 Deletion Syndrome

22q11.2 deletion syndrome (22q11DS) is associated with learning and cognitive dysfunctions and a high risk of developing schizophrenia. It has become increasingly clear that dendritic spine plasticity is tightly linked to cognition. Thus, understanding how genes involved in cognitive disorders affect synaptic networks is a major challenge of modern biology. Several studies have pointed to a spine density deficit in 22q11DS transgenic mice models. Using the LgDel mouse model, we first quantified spine deficit at different stages using electron microscopy. Next we performed repetitive confocal imaging over several days on hippocampal organotypic cultures of LgDel mice. We show no imbalanced ratio between daily spine formation and spine elimination, but a decreased spine life expectancy. We corrected this impaired spine stabilization process by overexpressing ZDHHC8 palmitoyltransferase, whose gene belongs to the LgDel microdeletion. Overexpression of one of its substrates, the cdc42 brain-specific variant, under a constitutively active form (cdc42-palm-CA) led to the same result. Finally, we could rescue spine density in vivo, in adult LgDel mice, by injecting pups with a vector expressing cdc42-palm-CA. This study reveals a new role of ZDHHC8-cdc42-palm molecular pathway in postsynaptic structural plasticity and provides new evidence in favor of the dysconnectivity hypothesis for schizophrenia.

Anti-TB drug concentrations and drug-associated toxicities among TB/HIV-coinfected patients

Background

Toxicities due to anti-TB treatment frequently occur among TB/HIV-coinfected patients.

Objectives

To determine the association between anti-TB drug concentrations and the occurrence of hepatotoxicity and peripheral neuropathy among TB/HIV-coinfected patients.

Methods

TB/HIV-coinfected patients were started on standard dose anti-TB treatment according to WHO guidelines. Anti-TB drug concentrations were measured using HPLC 1, 2 and 4 h after drug intake at 2, 8 and 24 weeks following initiation of TB treatment. Participants were assessed for hepatotoxicity using Division of AIDS toxicity tables and for peripheral neuropathy using clinical assessment of tendon reflexes, vibration sensation or symptoms. Cox regression was used to determine the association between toxicities and drug concentrations.

Results

Of the 268 patients enrolled, 58% were male with a median age of 34 years. Participants with no hepatotoxicity or mild, moderate and severe hepatotoxicity had a median C max of 6.57 (IQR 4.83-9.41) μg/mL, 7.39 (IQR 5.10-10.20) μg/mL, 7.00 (IQR 6.05-10.95) μg/mL and 3.86 (IQR 2.81-14.24) μg/mL, respectively. There was no difference in the median C max of rifampicin among those who had hepatotoxicity and those who did not ( P  =   0.322). There was no difference in the isoniazid median C max among those who had peripheral neuropathy 2.34 (1.52-3.23) μg/mL and those who did not 2.21 (1.45-3.11) μg/mL ( P  =   0.49).

Conclusions

There was no association between rifampicin concentrations and hepatotoxicity or isoniazid concentrations and peripheral neuropathy among TB/HIV-coinfected patients.

HPV prevalence and p16INKa overexpression in non-smoking non-drinking oral cavity cancer patients

OBJECTIVE

Our aim was to compare HPV and p16INK4a (p16) expression and their influence on survival and prognosis in oral cavity squamous cell cancer (OCSCC), between non-smokers and non-drinkers (NSND) and smokers and drinkers (SD).

SUBJECTS AND METHODS

Patients with OCSCC treated with surgery from 2000 to 2010 were included in the study. Patients who did not smoke at all or smoked less than 10 pack per years and did not drink alcohol on a daily basis were considered the NSND group. An equal number of SD were the control group. HPV presence was determined from paraffin-embedded blocks investigated by PCR analysis. p16 expression was evaluated with immunohistochemistry.

RESULTS

The NSND group were mostly younger or older female patients with tongue or gingival cancers. p16 expression was significantly more frequent in NSND patients (27% vs 10%). Patients with stronger p16 expression had significantly worse survival, especially for tongue cancers (P = 0.026). In Cox multivariate analysis, both HPV and p16 expression carried a negative prognosis for NSND patients (P = 0.0351 and P = 0.0260).

CONCLUSIONS

NSND are a specific population of OCSCC patients. In contrast to oropharyngeal cancer, HPV and p16 expression in OCSCC are negative predictive factors, especially in NSND patients.

[Recommendations regarding diagnosis and treatment of obsessive-compulsive symptoms in schizophrenia]

BACKGROUND

Obsessive-compulsive symptoms (OCS) are common in patients with schizophrenia. Although these symptoms are associated with an unfavourable course of the illness, in many cases they are not recognised or treated. The situation for patients with schizophrenia and obsessive-compulsive disorder (OCD) could improve considerably now that more advanced diagnostic techniques and better treatment options have been available.

AIM

To provide an overview of current knowledge regarding diagnosis and treatment options.

METHOD

We searched the literature for relevant articles.

RESULTS

With careful diagnosis OCS could be better noticed. Based on the time of onset of the OCS and the relationship between these symptoms and the use of antipsychotics, we propose a treatment strategy.

CONCLUSION

Cognitive behavioural therapy, as well as various pharmacotherapeutic strategies, are promising treatment options that could deployed more frequently to treat persistent OCD in schizophrenia. Although the research findings are homogeneous, the methodological quality of the studies is still low.

Usefulness of omalizumab in ten patients with severe occupational asthma

BACKGROUND

The management of severe occupational asthma (OA) remains problematic and new alternative treatments providing better disease control are required, ideally enabling affected individuals to remain in their job.

METHODS

Ten patients with severe uncontrolled OA were treated with the monoclonal anti-IgE antibody omalizumab. In six cases the causative agent was a high molecular weight (HMW) compound and in four cases it was a low molecular weight (LMW) chemical. All of the patients had well documented OA despite workplace adjustments.

RESULTS

During treatment, nine patients exhibited a lower rate of asthma exacerbations and used less oral or inhaled corticosteroids. Seven patients were able to continue working at the same workplace as before treatment.

CONCLUSION

We have demonstrated that omalizumab is a potential treatment for severe uncontrolled OA and enabled seven of the ten patients in the study to remain in their job.

None of the known different fibroblast growth-factor receptor-2 carboxy-terminal tails are restricted to cancer-cells

Fibroblast growth factor receptor-2 cDNAs derived from healthy tissues code for proteins with a 63 amino acid carboxy-terminal tail. Some cDNAs isolated from human tumour cDNA libraries code for receptors with 11, 15 or 29 amino acid carboxy-terminal tails. However, the important issue as to whether these latter tails are tumour specific markers has remained unresolved. We show that mRNAs coding for FGFR-2 proteins with carboxy-terminal tails of 11, 29 and 63 amino acids are co-expressed not only in many tumour tissues but also in normal human tissues, while the 15 amino acid tail appears to reflect a cloning artefact.

Alteration of the C-met oncogene locus in human head and neck-carcinoma

The c-met proto-oncogene encodes the receptor for the hepatocyte growth factor/scatter factor (HGF/SF) which induces eel proliferation and motility. We have analysed the genetic alteration involving the c-met locus on chromosome 7q31 using the pMet H polymorphic probe, in tumor and normal DNA from 87 patients with head and neck squamous cell carcinomas (HNSCC). We report the observation of loss of heterozygosity (LOH) at this locus in 23% of informative cases, contrasting with the previously reported 40% LOH detected in breast cancer. Further, gain of genetic material was also observed in 13% of the HNSCCs. The alterations of c-met gene were not significantly associated with standard pronostic features including tumor size and lymph node status. Involvement of the c-met locus in allelic imbalance, either loss or gain of genetic material, is relatively consistent with complex karyotype patterns detected in head and neck squamous cell carcinomas through previous cytogenetic studies.