Early platelet variation during concomitant chemo-radiotherapy predicts adjuvant temozolomide-induced thrombocytopenia in newly diagnosed glioblastoma patients

PURPOSE

Temozolomide (TMZ) is known to induce thrombocytopenia but no early predictive test has yet been clearly established. The aim of the study was to retrospectively identify and validate a threshold of early platelet variation predicting TMZ-induced thrombocytopenia during the TMZ phase in patients treated according to the Stupp protocol for glioblastoma.

METHODS

A training set was used to analyze variations in platelet count occurring from the first week (W1) to week 6 (W6) during radiotherapy. Our aim was to identify the most relevant platelet decrease associated with TMZ-induced thrombocytopenia ≤ 100 G/L at day 28 during the TMZ phase. The performance of the threshold was confirmed in an independent validation set.

RESULTS

Overall, 147 patients were included, 85 and 62 in the training and validation sets, respectively. Twenty-seven patients (18%) experienced at least one TMZ-induced thrombocytopenia in the TMZ phase. A platelet decrease at W6 ≥ 35% (∆W6 ≥ 35%) was identified as the best predictive variation with an AUC of 0.83, a sensitivity of 65%, and a specificity of 96%. In the validation set, ∆W6 ≥ 35% platelet variation was identified as an independent marker of TMZ-induced thrombocytopenia during the TMZ phase (OR 15.23 (95% CI 3.5-107.5)) corresponding to sensitivity of 77% (66-87%), specificity of 73% (62-84%), a positive predictive value of 42% (29-54%), and a negative predictive value of 92% (86-99%).

CONCLUSION

Platelet decrease at W6 ≥ 35% during the RT-TMZ phase is an early and simple predictive marker of clinically relevant TMZ-induced thrombocytopenia during TMZ maintenance.

Frequent attendance and the concordance between PHQ screening and GP assessment in the detection of common mental disorders

OBJECTIVE

Frequent Attenders (FAs) have high rates of both common mental disorders (CMD) and physical disorders, partly justifying this service use behaviour. This study examines both case and non-case concordance between CMDs as estimated by a self-report screening questionnaire and as rated by the general practitioner (GP), in FAs compared to Other Attenders (OAs).

METHODS

2275 patients of an overlapping sample of 55 GPs from 2 surveys performed 10 years apart, completed in the waiting room the Patient Health Questionnaire (PHQ) and Client Service Receipt Inventory on 6-month service use. For each patient, the GP rated mental health on a 0-4 scale, with a clear indication that scores of 2 and above referred to caseness. PHQ-CMDs included major and other depressive, anxiety, panic, and somatoform disorders, identified using the original PHQ DSM-IV criteria-based algorithms. FA was defined as the top 10% of attenders in age, sex and survey-year stratified subgroups.

RESULTS

FAs had higher rates of PHQ-CMDs (42% versus 23% for OAs, p < .0001). They reported more personal and social problems, disability and had higher GP-rated physical illness. Survey-day antidepressant/anxiolytic medication prescription was higher for FAs (p < .0001), with (p = .02) but also without a CMD (p < .0001). Both GP/PHQ case and non-case concordance differed between FAs and OAs, with a non-case concordance odds ratio of 0.5 (95% CI: 0.3-0.7, p = .001) for FAs compared to OAs.

CONCLUSION

Despite a greater likelihood of GPs detecting CMDs in FAs, our findings suggest a potential risk of 'over-detection' of patients not reaching CMD threshold criteria among FAs.

Von Willebrand Factor and Mitral Valve Prolapse

The levels of von Willebrand factor (vWF: Ag) were measured in 27 patients with mitral valve prolapse (MVP) and compared to 27 age matched controls. Decreased levels of vWF:Ag (<80%) were found in 59% (16/27) of those with MVP compared to only 7% (2/27) of the controls (p <0.001). Mean vWF: Ag levels were also significantly lower in those with MVP (68 ± 30% versus 100 ± 23%, p <0.001). In those with MVP and congestive heart failure secondary to ruptured chordae tendineae, however, the mean level of vWF:Ag was not significantly different from control values (95 ± 32). There was an increased incidence of recurrent nose bleeds in those with MVP and low levels of vWF: Ag. We conclude that there is a relationship between MVP and low levels of vWF:Ag which may explain the increased incidence of epistaxis in such patients. Increased release of vWF: Ag in those with MVP and concomitant congestive heart failure may account for the normal levels found in this subgroup.

Relative Sensitivity of Different Tests in the Detection of Low Titer Lupus Anticoagulants

Lupus anticoagulants (LA) and anticardiolipin antibodies have been strongly associated with recurrent abortion and fetal death. Because steroids have been reported to improve the fetal outcome of LA associated pregnancies, presumably by decreasing the levels of LA, it becomes desirable to have a simple and reliable test to monitor the levels of the putative antibody. To this effect, we assessed the capacity of the following coagulation tests to detect the presence of LA in serial dilutions of patient plasma with pooled normal plasma: kaolin clotting time (KCT), tissue thromboplastin inhibition test (TTIT), dilute Russell Viper venom time (DRVVT) and activated partial thromboplastin time with standard and high concentrations of phospholipids (SC and HCAPTT). All samples were also evaluated for the presence of anticardiolipin antibodies with an ELISA. The KCT was able to detect LA at a much greater dilution in normal plasma than any of the other clotting assays. The ELISA was comparable to KCT in its ability to detect high dilutions of LA.

Systematic review of the cost-effectiveness of preoperative antibiotic prophylaxis in reducing surgical-site infection

BACKGROUND

Surgical-site infections (SSIs) increase the length of hospital admission and costs. SSI prevention guidelines include preoperative antibiotic prophylaxis. This review assessed the reporting quality and cost-effectiveness of preoperative antibiotics used to prevent SSI.

METHODS

PubMed, Web of Science, Cumulative Index to Nursing and Allied Health Literature, Index of Economic Articles (EconLit), Database of Abstracts of Reviews of Effect (including the National Health Service Economic Evaluation Database) and Cochrane Central databases were searched systematically from 1970 to 2017 for articles that included costs, preoperative antibiotic prophylaxis and SSI. Included were RCTs and quasi-experimental studies conducted in Organisation for Economic Co-operation and Development countries with participants aged at least 18 years and published in English. Two reviewers assessed eligibility, with inter-rater reliability determined by Cohen's κ statistic. The Consolidated Health Economic Evaluation and Reporting Standards (CHEERS) and modified Drummond checklists were used to assess reporting and economic quality. Study outcomes and characteristics were extracted, and incremental cost-effectiveness ratios were calculated, with costs adjusted to euros (2016) (€1 = US $1·25; £1 sterling = €1·28).

RESULTS

Twelve studies published between 1988 and 2014 were included from 646 records identified; nine were RCTs, two were nested within RCTs and one was a retrospective chart review. Study quality was highest in the nested studies. Cephalosporins (first, second and third generation) were the most frequent prophylactic interventions. Eleven studies demonstrated clinically effective interventions; ten were cost-effective (the intervention was dominant); in one the intervention was dominated by the control; and in one the intervention was more effective and more expensive than the control.

CONCLUSION

Preoperative antibiotic prophylaxis does reduce SSI, costs to hospitals and health providers, but the reporting of economic methods in RCTs is not standardized. Routinely nesting economic methods in RCTs would improve economic evaluations and ensure appropriate selection of prophylactic antibiotics.

Impact of baseline clinical and laboratory features on the risk of thrombosis in children with acute lymphoblastic leukemia: A prospective evaluation

BACKGROUND

Children with acute lymphoblastic leukemia (ALL) have increased risk of thromboembolism (TE). However, the predictors of ALL-associated TE are as yet uncertain.

OBJECTIVE

This exploratory, prospective cohort study evaluated the effects of clinical (age, gender, ALL risk group) and laboratory variables (hematological parameters, ABO blood group, inherited and acquired prothrombotic defects [PDs]) at diagnosis on the development of symptomatic TE (sTE) in children (aged 1 to ≤18) treated on the Dana-Farber Cancer Institute ALL 05-001 study.

PROCEDURES

Samples collected prior to the start of ALL therapy were evaluated for genetic and acquired PDs (proteins C and S, antithrombin, procoagulant factors VIII (FVIII:C), IX, XI and von Willebrand factor antigen levels, gene polymorphisms of factor V G1691A, prothrombin gene G20210A and methylene tetrahydrofolate reductase C677T, anticardiolipin antibodies, fasting lipoprotein(a), and homocysteine).

RESULTS

Of 131 enrolled patients (mean age [range] 6.4 [1-17] years) 70 were male patients and 20 patients (15%) developed sTE. Acquired or inherited PD had no impact on the risk of sTE. Multivariable analyses identified older age (odds ratio [OR] 1.13; 95% confidence interval [CI]: 1.01, 1.26) and non-O blood group (OR 3.64, 95% CI: 1.06, 12.51) as independent predictors for development of sTE. Patients with circulating blasts had higher odds of developing sTE (OR 6.66; 95% CI: 0.82, 53.85).

CONCLUSION

Older age, non-O blood group, and presence of circulating blasts, but not PDs, predicted the risk of sTE during ALL therapy. We recommend evaluation of these novel risk factors in the development of ALL-associated TE. If confirmed, these easily accessible variables at diagnosis can help develop a risk-prediction model for ALL-associated TE.

Structural model, functional modulation by ivermectin and tissue localization of Haemonchus contortus P-glycoprotein-13

Haemonchus contortus, one of the most economically important parasites of small ruminants, has become resistant to the anthelmintic ivermectin. Deciphering the role of P-glycoproteins in ivermectin resistance is desirable for understanding and overcoming this resistance. In the model nematode, Caenorhabditis elegans, P-glycoprotein-13 is expressed in the amphids, important neuronal structures for ivermectin activity. We have focused on its ortholog in the parasite, Hco-Pgp-13. A 3D model of Hco-Pgp-13, presenting an open inward-facing conformation, has been constructed by homology with the Cel-Pgp-1 crystal structure. In silico docking calculations predicted high affinity binding of ivermectin and actinomycin D to the inner chamber of the protein. Following in vitro expression, we showed that ivermectin and actinomycin D modulated Hco-Pgp-13 ATPase activity with high affinity. Finally, we found in vivo Hco-Pgp-13 localization in epithelial, pharyngeal and neuronal tissues. Taken together, these data suggest a role for Hco-Pgp-13 in ivermectin transport, which could contribute to anthelmintic resistance.

Effect of age and hearing loss on auditory stream segregation of speech sounds

Segregating and understanding speech in complex environments is a major challenge for hearing-impaired (HI) listeners. It remains unclear to what extent these difficulties are dominated by direct interference, such as simultaneous masking, or by a failure of the mechanisms of stream segregation. This study compared older HI listeners' performance with that of young and older normal-hearing (NH) listeners in stream segregation tasks involving speech sounds. Listeners were presented with sequences of speech tokens, each consisting of a fricative consonant and a voiced vowel (CV). The CV tokens were concatenated into interleaved sequences that alternated in fundamental frequency (F0) and/or simulated vocal tract length (VTL). Each pair of interleaved sequences was preceded by a "word" consisting of two random tokens. The listeners were asked to indicate whether the word was present in the following interleaved sequences. The word, if present, occurred within one of the interleaved sequences, so that performance improved if the listeners were able to perceptually segregate the two sequences. Although HI listeners' identification of the speech tokens in isolation was poorer than that of the NH listeners, HI listeners were generally able to use both F0 and VTL cues to segregate the interleaved sequences. The results suggest that the difficulties experienced by HI listeners in complex acoustic environments cannot be explained by a loss of basic stream segregation abilities.

Identification and characterization of highly versatile peptide-vectors that bind non-competitively to the low-density lipoprotein receptor for in vivo targeting and delivery of small molecules and protein cargos

Insufficient membrane penetration of drugs, in particular biotherapeutics and/or low target specificity remain a major drawback in their efficacy. We propose here the rational characterization and optimization of peptides to be developed as vectors that target cells expressing specific receptors involved in endocytosis or transcytosis. Among receptors involved in receptor-mediated transport is the LDL receptor. Screening complex phage-displayed peptide libraries on the human LDLR (hLDLR) stably expressed in cell lines led to the characterization of a family of cyclic and linear peptides that specifically bind the hLDLR. The VH411 lead cyclic peptide allowed endocytosis of payloads such as the S-Tag peptide or antibodies into cells expressing the hLDLR. Size reduction and chemical optimization of this lead peptide-vector led to improved receptor affinity. The optimized peptide-vectors were successfully conjugated to cargos of different nature and size including small organic molecules, siRNAs, peptides or a protein moiety such as an Fc fragment. We show that in all cases, the peptide-vectors retain their binding affinity to the hLDLR and potential for endocytosis. Following i.v. administration in wild type or ldlr-/- mice, an Fc fragment chemically conjugated or fused in C-terminal to peptide-vectors showed significant biodistribution in LDLR-enriched organs. We have thus developed highly versatile peptide-vectors endowed with good affinity for the LDLR as a target receptor. These peptide-vectors have the potential to be further developed for efficient transport of therapeutic or imaging agents into cells -including pathological cells-or organs that express the LDLR.