Expansion of highly differentiated CD8+ T-cells or NK-cells in patients treated with dasatinib is associated with cytomegalovirus reactivation

The tyrosine kinase inhibitor dasatinib exerts immunosuppressive effects on T-cells and NK-cells in vitro. However, in some dasatinib-treated leukemia patients, clonal lymphocytosis with large granular lymphocyte (LGL) morphology develops, and this is associated with enhanced therapeutic responses. To elucidate the mechanistic basis for this paradoxical observation, we conducted detailed phenotypic and functional analyses of T-cell and NK-cell populations from 25 dasatinib-treated leukemia patients. All tested patients with LGL expansions (15/16) were cytomegalovirus (CMV) immunoglobulin (IgG) seropositive with high frequencies of CMV-specific CD8(+) T-cells; 5/16 LGL patients also experienced symptomatic CMV reactivation during dasatinib therapy. Expanded T-cell and NK-cell populations exhibited late differentiated (CD27(-)CD57(+)) phenotypes; this was associated with a predisposition to apoptosis within the T-cell compartment and impaired NK-cell cytotoxicity. Only 3/9 non-LGL patients were CMV IgG seropositive. Dasatinib inhibited in vitro lymphocyte functions, similarly in LGL patients and controls. Notably, distinct CD8(high) and CD8(low) T-cell subsets were observed in LGL patients; this phenotypic dichotomy was also apparent in CMV-specific CD8(+) T-cell populations, and exhibited features consistent with antigen-driven activation. In addition, plasma levels of IP-10, IL-6, monokine induced by interferon-γ and interleukin-2R were significantly increased in LGL patients. These data provide evidence that dasatinib-associated LGL expansion is linked to CMV reactivation and suggest a potential mechanism for this phenomenon.

Bioreductive therapies: an overview of drugs and their mechanisms of action

PURPOSE

Bioreductively activated drugs have been used as antimicrobials, chemotherapeutic agents, and radiation sensitizers. The present paper is an overview of their mechanism of action and application in the treatment of cancer.

MATERIALS AND METHODS

Drugs such as nitroimidazoles, mitomycins, and benzotriazine di-N-oxides were a focus of this research. Studies have ranged from the chemistry of the reductive process of activation to in vitro and in vivo studies in rodent and human cells, through to clinical testing. The variety of techniques and test systems brought to bear on these compounds is a strength of this field of research.

RESULTS

A detailed chemical understanding of the mechanism of action of a variety of bioreductives is now available. The enzymatic processes by which these drugs are activated and the cofactors involved in this activation are becoming well understood. Recent advances have been made in the design and use of dual-function bioreductives, bioreductive triggers of drug activation, and DNA-targeted bioreductives. Significant success has been demonstrated clinically with bioreductive drugs, used in combination with radiation and front-line chemotherapeutic agents. The areas of antibody-directed enzyme prodrug therapy (ADEPT) and gene-directed enzyme prodrug therapy (GDEPT) are identified as new directions for bioreductive therapy.

CONCLUSION

The use of bioreductively-activated drugs for the treatment of cancer has made steady progress. The success obtained clinically and the new molecular approaches currently being implemented promise significant advances in the future.

Rapid mobilization of cytotoxic lymphocytes induced by dasatinib therapy

Tyrosine kinase inhibitors (TKIs) have potent effects on malignant cells, and they also target kinases in normal cells, which may have therapeutic implications. Using a collection of 55 leukemia patients treated with TKI therapy (chronic myeloid leukemia, n=47; acute lymphoblastic leukemia, n=8), we found that dasatinib, a second-generation broad-spectrum TKI, induced a rapid, dose-dependent and substantial mobilization of non-leukemic lymphocytes and monocytes in blood peaking 1-2 h after an oral intake and the blood counts closely mirrored drug plasma concentration. A preferential mobilization was observed for natural killer (NK), NK T, B and γδ+ T cells. Mobilization was coupled with a more effective transmigration of leukocytes through an endothelial cell layer and improved cytotoxicity of NK cells. Platelet numbers decreased markedly after the drug intake in a proportion of patients. Similar effects on blood cell dynamics and function were not observed with any other TKI (imatinib, nilotinib and bosutinib). Thus, dasatinib induces a unique, rapid mobilization and activation of cytotoxic, extravasation-competent lymphocytes, which may not only enhance antileukemia immune responses but can also be causally related to the side-effect profile of the drug (pleural effusions, thrombocytopenia).

Alterations in phospholipidomic profile in the brain of mouse model of depression induced by chronic unpredictable stress

Depression is a worldwide disability disease associated with high morbidity and has increased dramatically in the last few years. The differential diagnosis and the definition of an individualized therapy for depression are hampered by the absence of specific biomarkers. The aim of this study was to evaluate the phospholipidomic profile of the brain and myocardium in a mouse model of depression induced by chronic unpredictable stress (CUS). The lipidomic profile was evaluated by thin layer and liquid chromatography and mass spectrometry and lipid oxidation was estimated by FOX II assay. Antioxidant enzyme activity and the oxidized/reduced glutathione (GSH/GSSG) ratio were also evaluated. Results showed that chronic stress affects primarily the lipid profile of the brain, inducing an increase in lipid hydroperoxides, which was not detected in the myocardium. A significant decrease in phosphatidylinositol (PI) and in cardiolipin (CL) relative contents and also oxidation of CL and a significant increase of phosphatidylcholine (PC) and phosphatidylethanolamine (PE) were observed in the brain of mice after unpredictable chronic stress conditions. In the myocardium only an increase in PC content was observed. Nevertheless, both organs present a decreased GSH/GSSG ratio when compared to control groups, corroborating the occurrence of oxidative stress. The enzyme activities of catalase (CAT) and superoxide dismutase (SOD) were found to be decreased in the myocardium and increased in the brain, while glutathione reductase (GR) was decreased in the brain. Our results indicate that in a mouse model for studying depression induced by CUS, the modification of the expression of oxidative stress-related enzymes did not prevent lipid oxidation in organs, particularly in the brain. These observations suggest that depression has an impact on the brain lipidome and that further studies are needed to better understand lipids role in depression and to evaluate their potential as future biomarkers.

Headache in Acute Stroke. A Prospective Study in the First 8 Days

We aimed to describe and classify headaches associated with acute stroke, by interviewing patients consecutively admitted to a stroke unit using a validated headache questionnaire and the International Classification of Headache Disorders of the International Headache Society (IHS). One hundred and twenty-four patients (61% ischaemic and 39% haemorrhagic stroke) reported headache. Headaches started mostly on the day of stroke, were more often continuous, pressure-type, bilateral and located in the anterior region, were increased by movement and by cough and lasted for a mean of 3.8 days. Tension-type was the most frequent type of headache. Eleven per cent of headaches could not be classified using the criteria of the IHS. Previous primary headache was documented in 71 patients. The presence of nausea/vomiting due to acute stroke can confound headache classification using the IHS criteria. In up to half of the patients, headache seems to be a reactivation of previous primary headache.

The influence of expression of P-glycoprotein on the penetration of anticancer drugs through multicellular layers

The success of chemotherapy in the treatment of solid tumours may be limited by cellular mechanisms leading to drug resistance and/or by the slow penetration of drugs through tissue, resulting in a steep concentration gradient from tumour blood vessels. One mechanism leading to the development of multidrug resistance is overexpression of the membrane-based export pump P-glycoprotein (P-gp). The relationship between expression of P-gp by constituent cells and the penetration of P-gp substrates through tissue was studied by comparing the penetration of P-gp substrates through multicellular layers derived from either wild-type or P-gp overexpressing cell lines. P-gp reversal agents were added to confirm the contribution of P-gp in influencing the penetration of its substrates. Our data indicate: 1) penetration of the P-gp substrates, 99mTc-sestaMIBI and 14C-doxorubicin, is greater through multicellular layers formed from P-gp overexpressing cell lines as compared with wild-type cells; 2) the addition of agents that inhibit the function of P-gp results in decreased penetration of these substrates through multicellular layers with P-gp expression. There was no effect of P-gp reversal agents on penetration of 14C-sucrose or of 3H-5-fluorouracil (non-substrate controls). Our data suggest that the administration of agents that inhibit the function of P-gp might have opposing effects on therapeutic index in solid tumours: increased sensitivity of perivascular tumour cells but decreased penetration of P-gp substrates to more distal cells. These effects may explain, in part, the limited therapeutic benefit for solid tumours that has accrued from use of agents that reverse the effects of P-gp.

Studies of 99mTc-BnAO (HL-91): a non-nitroaromatic compound for hypoxic cell detection

PURPOSE

Solid tumours of similar type and stage can vary widely in their hypoxic cell fraction. Such cells may be prognostic for aggressive, metastatic, and radiation-resistant disease. A 99mtechnetium (99mTc)-labelled non-nitroaromatic agent, butyleneamine oxime (99mTc-BnAO) or HL-91 (Amersham International, Inc., Amersham, UK) has been evaluated both in vitro and in vivo for its possible efficacy as a noninvasive marker for the clinical detection of hypoxic cells in solid tumours.

MATERIALS AND METHODS

Suspension cultures of Chinese hamster ovary (CHO) cells under controlled levels of oxygen were used to measure the oxygen dependency of 99mTc-BnAO accumulation. V79 cells grown as multilayers on a semipermeable membrane served as an in vitro model for drug penetration through the extravascular space of the tumour. C3H mice bearing KHT-C leg tumours were the in vivo models for selective drug accumulation as a function of time after i.v. administration of 99mTc-BnAO.

RESULTS

99mTc accumulated selectively in hypoxic vs. aerobic cells, resulting in a 9 +/- 2-fold differential in radioactivity per cell at 4 h. The k(m) for this selective accumulation was 20 ppm of oxygen. The labelled drug was equally effective in penetrating the cellular multilayer under aerobic or hypoxic conditions. In vivo measurements indicated favourable labelling of solid tumours containing hypoxic cells with 1% of the total activity per g of tumour, a tumour-to-blood ratio of 1.2, and a tumour-to-muscle ratio of 4.6 at 4 to 6 h after drug administration. In contrast to more lipophilic 99mTc- labelled compounds, excretion was primarily via the urinary tract. Nitro-L-arginine selectively increased solid tumour labelling over normal tissue.

CONCLUSIONS

99mTc-BnAO or HL-91 is a promising agent for clinical studies of tumour hypoxia, although the mechanism of its selective hypoxic cell accumulation remains unexplained.

Cellular accumulation and retention of the technetium-99m-labelled hypoxia markers BRU59-21 and butylene amine oxime

BRU59-21 and 99mTc-butylene amine oxime (BnAO, HL91) are being evaluated for imaging hypoxia in tumors. Both tracers: 1) rapidly reached a plateau in aerobic Chinese hamster ovary cells in vitro but continuously accumulated in hypoxic cells; 2) ceased to accumulate when hypoxic cells were exposed to air; 3) showed approximately 40% retention upon washing the cells; 4) showed selective hypoxic accumulation only at 37 degrees C; 5) accumulation could be modulated by addition of electron-affinic compounds; and 6) exhibited higher accumulation in cells which overexpress cytochrome P450 reductase. Both BRU59-21 and 99mTc-BnAO share properties making them suitable for hypoxia imaging.

Role of NADPH:cytochrome P450 reductase in the hypoxic accumulation and metabolism of BRU59-21, a technetium-99m-nitroimidazole for imaging tumor hypoxia

Nitroimidazoles labeled with technetium-99m are being investigated as non-invasive markers of tumor hypoxia. They are bioreductive compounds that require enzymatic reduction for retention in hypoxic cells, but little is known about the cellular factors affecting their accumulation in hypoxic cells. If the absolute accumulation of hypoxia markers is affected by enzyme levels, an inaccurate assessment of the hypoxic cell fraction in tumors may occur. BRU59-21, (99m)Tc-oxo[[3,3,9, 9-tetramethyl-6-[(2-nitro-1H-imidazol-1-yl)methyl]5-oxa-4, 8-diazadioximato]-(3-)-N,N',N",N"'] technetium (V), a technetium-99m-nitroimidazole that is being studied as a potential marker of tumor hypoxia, was used in the present study to evaluate the effect of NADPH:cytochrome P450 reductase (EC 1.6.2.4) levels on BRU59-21 accumulation and metabolism. Metabolism of BRU59-21 in hypoxic cellular lysates derived from Chinese hamster ovary cells overexpressing NADPH:cytochrome P450 reductase was 8-fold greater than in control cells. This effect required the presence of exogenous NADPH. The increased metabolism of BRU59-21 in lysates overexpressing NADPH:cytochrome P450 reductase was inhibited at 4 degrees and by the addition of NADPH:cytochrome P450 reductase inhibitors. The addition of inhibitors of other nitroreductase enzymes had no effect on BRU59-21 metabolism in these lysates. When the accumulation and metabolism of BRU59-21 were studied in stirred suspension cultures, it was found that cells overexpressing NADPH:cytochrome P450 reductase exhibited about a 3-fold increase in both the hypoxic metabolism and the accumulation of BRU59-21. These findings suggest that NADPH:cytochrome P450 reductase is an important enzyme in BRU59-21 metabolism in model systems of tumor hypoxia.

Modifying the in vitro accumulation of BMS181321, a technetium-99m-nitroimidazole, with unlabelled nitroaromatics

BMS181321, [99mTc]oxo[[3,3,9,9-tetramethyl-1-(2-nitro-1H-imidazol-1-yl)-4,8-diaz aundecane-2,10-dione dioximato]-(3)-N,N',N",N"']technetium, is a 99mTc-nitroimidazole that is being investigated as a hypoxic marker in tumors. Due to the high specific activity of 99mTc, the concentration of BMS181321 used in its applications is very low. Metabolic depletion and non-specific binding of the drug may limit its ability to fully map out hypoxic regions. An attempt has been made to modify the in vitro accumulation of BMS181321 in hypoxic Chinese hamster ovary (CHO) cells with unlabelled nitroaromatics. The 2-nitroimidazole etanidazole (0.08 to 8 mM) caused a concentration-dependent decrease in BMS181321 accumulation to 70-28% and metabolism to 70-40% of the control level in hypoxic cells at 4 hr. In contrast, the 5-nitroimidazole tinidazole (0.09 to 9 mM) caused a concentration-dependent increase in BMS181321 accumulation to 110-170% and metabolism to 100-150% of the control level in hypoxic cells at 4 hr. Nitroaromatics with an electron affinity similar to or greater than that of BMS181321 inhibited its accumulation and metabolism, and 5-nitroimidazoles, which have an electron affinity lower than that of BMS181321, enhanced its accumulation and metabolism. The enhanced accumulation with the addition of metronidazole was not observed in the presence of low oxygen levels or of a nitrofuran of higher electron affinity than BMS181321. These results suggest that a competition for reducing equivalents and/or for the BMS181321 radical anion itself can occur in cells, leading to the inhibition of BMS181321 reduction in the presence of nitroaromatics of similar or greater electron affinity. A transfer of electrons from the radical anion form of the reduced 5-nitroimidazole to the more electron affinic BMS181321 compound may occur, causing increased hypoxic accumulation of BMS181321.

Preventing HIV under financial constraints: The 2011-12 reform of the Portuguese HIV/AIDS Programme

The national HIV/AIDS Programme has been a core health programme in Portugal, and has led the country's response to the HIV epidemics since the 1980s. In 2011, the Portuguese Government reorganised central services and reformed all vertical programmes, including the HIV/AIDS Programme. This paper describes the main features of that reform and analyses selected outcomes, as well as how those financial constraints affected the response to HIV/AIDS. Despite some transitory cuts in spending, the National Programme for HIV/AIDS Infection was able to successfully expand testing and prevention interventions. Strategic partnerships with non-governmental and community-based organisations were crucial to continue delivering adequate HIV testing services and reaching most-at-risk groups. Scaling-up access to pre-exposure prophylaxis (PrEP), improving access and adherence to antiretroviral therapy, and continuously promoting access to HIV testing services and HIV self-testing are the main challenges that the National Programme for HIV/AIDS Infection will face in the upcoming years.

BRU59-21, a second-generation 99mTc-labeled 2-nitroimidazole for imaging hypoxia in tumors

Hypoxia in tumors is believed to be an important cause of local failure of radiotherapy in certain types of cancer. BRU59-21 (BMS194796) is a second-generation 99mTc-labeled 2-nitroimidazole that has been shown to offer improved characteristics for imaging myocardial ischemia. It has now been evaluated in models of tumor hypoxia.

METHODS

Accumulation of BRU59-21 was compared with that of BMS181321 in Chinese hamster ovary cells incubated under aerobic or hypoxic conditions. The effects of competition with unlabeled nitroimidazoles and oxygen were studied. Biodistribution studies were performed in mice bearing transplanted KHT-C tumors in the leg.

RESULTS

Within 5 min, BRU59-21 partitioned into aerobic cells in vitro at a level 10 times higher than external medium with no further increase over time. In hypoxic cells this initial partitioning was followed by selective accumulation to levels 5 times higher than in aerobic cells by 4 h. Low levels of oxygen (approximately 40 ppm) inhibited the maximal accumulation rate by 50%. Unlabeled misonidazole, a 2-nitroimidazole, inhibited accumulation of radioactivity, whereas tinidazole, a 5-nitroimidazole, enhanced accumulation; similar effects had been reported with BMS181321. Biodistribution studies in mice showed rapid clearance of radioactivity from the blood, resulting in enhanced tumor-to-blood ratios compared with BMS181321. Increasing the hypoxic fraction in the tumor by injection of nitro-L-arginine resulted in increased retention of tracer in the tumor without affecting other tissues.

CONCLUSION

These results suggest that BRU59-21 warrants further investigation as an agent for imaging tumor hypoxia in the clinic.

Reference values for the cross-sectional area of the lumbar multifidus muscle in children

BACKGROUND

The multifidus muscle plays a major role in the growth and postural control of children. Therefore, the reference values of the cross-sectional area (CSA) of the lumbar multifidus muscle represent an important tool for assessing muscle development and the early monitoring of musculoskeletal disorders.

OBJECTIVE

The aim of this study was to provide percentile scores for the CSA of the lumbar multifidus muscle in eutrophic children aged 5 to 10 years.

METHODS

This was a cross-sectional, observational study, involving 736 children. An anthropometric assessment was conducted and ultrasound (US) imaging was used to assess the CSA of the lumbar (vertebral level L5) multifidus muscle. The CSA was expressed as percentile scores.

RESULTS

The CSA in the boys ranged from 1.8 cm2 to 5.3 cm2 and in girls from 1.9 cm2 to 5.9 cm. The CSA in the 50th percentile scores of both sexes was 3.4 cm2. There was an increase in the CSA between 5 and 7 years old in both sexes. The CSA presented a greater variance in girls than in boys. After 8 years of age, the multifidus CSA increased in girls and decreased in boys.

CONCLUSION

The present study has provided percentile scores for the CSA of the lumbar multifidus muscle for eutrophic children aged 5 to 10 years. An increase was observed of the CSA of the multifidus muscle between the ages of 5 and 7 years and there were no differences in the CSA percentiles in relation to sex. An increase in the CSA after 8 years of age was only observed in the girls.

BMS181321 accumulation in rodent and human cells: the role of P-glycoprotein

A 2-nitroimidazole with a side chain that contains technetium-99m as a chelate, BMS181321, is undergoing evaluation as an imaging agent for myocardial and cerebral ischaemia, as well as a diagnostic probe for hypoxic cells in solid tumours. Its accumulation in hypoxic and aerobic populations of three lines of Chinese hamster ovary cells of differing P-glycoprotein status, as well as one rat and two human cell lines has been determined. There was selective accumulation of BMS181321 in hypoxic vs aerobic cells. P-glycoprotein level was not a factor in this accumulation and hypoxic human cells accumulated BMS181321 more rapidly than the rodent cells. These results indicate P-glycoprotein levels in tumour cells will not confound the use of BMS181321 as a hypoxic cell marker.

The accuracy of computerized biophotogrammetry in diagnosing changes in the cervical spine and its reliability for the cervical lordosis angle

BACKGROUND

Accuracy studies of biophotogrammetry protocols require standardization similar to radiography.

OBJECTIVE

To estimate the diagnostic accuracy of a biophotogrammetric assessment protocol for cervical hyperlordosis, compared to radiography, and its intra- and inter-examiner reliability for measuring the cervical lordosis angle.

METHODS

A study of diagnostic accuracy in women complaining of cervical pain. Two photos were taken using the CorelDraw biophotogrammetric protocol and one radiograph using the Cobb C1-C7 method. The Intra- and Inter-examiner reliability was calculated using the Kappa index and the intraclass correlation coefficient (ICC). The Bland-Altman plot and the ROC curve were presented.

RESULTS

The sample consisted of 19 women. The accuracy of biophotogrammetry was 94.73% and the reliability between biophotogrammetry and radiography presented an ICC of 0.84 and a Kappa of 0.87. The excellent intra (ICC = 0.94) and inter-examiner (ICC = 0.86) reliability of the biophotogrammetry was confirmed. The area under the ROC curve was 93.5%. The Bland-Altman plot indicated differences between the two instruments close to the mean (1.5∘).

CONCLUSION

The biophotogrammetric protocol proved to be accurate in diagnosing cervical hyperlordosis, with excellent reliability between the biophotogrammetric and radiographic assessments. It also demonstrated excellent intra- and inter-examiner reliability in measuring the cervical lordosis angle.

Postural deviation patterns, trunk mobility restriction and spinal musculoskeletal dysfunctions in chronic gastritis

OBJECTIVE

This study aimed to compare posture, trunk mobility, and spinal musculoskeletal dysfunctions between adults diagnosed with chronic gastritis and healthy individuals.

STUDY DESIGN

Cross-sectional observational study.

METHODS

A total of 88 participants were included, divided into a gastritis group (GG = 41) and a comparison group (CG = 47). Posture and trunk mobility were assessed using computerized photogrammetry, while spinal musculoskeletal dysfunctions were evaluated using the tenderness, asymmetry, restriction of motion, and tissue texture change (TART) tool. Cohen's d effect sizes were calculated for the Student's t-test, and Phi coefficient (ϕ) and Cramér's V were used for Chi-square tests. Bonferroni correction was applied for multiple comparisons.

RESULTS

The GG showed a significantly higher percentage of left trunk deviation (68.3%; p = 0.005, ϕ = 0.153) and right trunk rotation (80.5%; p = 0.02, V = 0.300) compared to the CG. The GG also exhibited significantly reduced trunk flexion (mean difference = 8.79°, p = 0.013, d = 0.55) and left rotation (mean difference = 7.78°, p = 0.020, d = 0.50) compared to the CG. Additionally, the GG presented greater restrictions in passive mobility to the left for rotation and lateral glide, as well as asymmetry, pain, and increased muscle tension at multiple cervical and thoracic levels, particularly at C3, C4, T8, and T9 (ϕ ranging from 0.27 to 0.68), which remained significant after Bonferroni correction (p < 0.001).

CONCLUSION

The findings suggest that chronic gastritis is associated with compensatory postural adaptations, reduced trunk mobility, and spinal musculoskeletal dysfunctions. These results highlight the potential for visceral disturbances to contribute to biomechanical imbalances, likely due to the viscerosomatic reflex mechanism, reinforcing the need for integrative clinical approaches that address both gastrointestinal and musculoskeletal systems in the management of chronic gastritis.

Home exercises for neck pain: A Delphi survey

PURPOSE

The current context of the COVID-19 pandemic has demonstrated the need for home exercise strategies for the relief of neck pain, which, in recent times, has increased. However, there is a gap regarding home exercises that are aimed at reducing neck pain. Therefore, the aim of this study was to develop, validate and culturally adapt a home exercise protocol for neck pain.

METHODS

This was an observational study conducted in three stages: (1) Developing an online search of databases for articles on neck pain exercises. (2) Validating a panel of 12 physical therapists, using the Delphi technique, and (3) Cultural adaptation, through face-to-face assessment with individuals aged 18-30 years with neck pain (n = 15). This resulted in the production of a final version of the protocol. Consensus on the protocol items (using the five-point Likert scale) was considered when the percent agreement was equal to or greater than 75%. Individuals were also asked about pain intensity during the last week before and after performing the protocol.

RESULTS

A protocol was developed with the principles of neck and scapular stabilization and upper limb movements, for a period of 4 weeks. Nine physical therapists completed two rounds online, and all items in the second version of the protocol presented an agreement of over 75%. The protocol was culturally adapted by the target population, in which 73% of individuals presented pain reduction with a minimally clinically important difference.

CONCLUSION

A 4-week home exercise protocol was created based on the best evidence in the literature, was validated by physical therapists and adapted for the population with neck pain. It proved to be an understandable, useful, practical and convenient tool in the treatment of this disorder and demonstrated an improvement in neck pain.

CLINICALTRIALS

GOV: (NCT04187001).