Desoxyepothilone B: an efficacious microtubule-targeted antitumor agent with a promising in vivo profile relative to epothilone B

A new class of 16-membered macrolides, the epothilones (Epos), has been synthesized and evaluated for antitumor potential in vitro and in vivo. Recent studies in these and other laboratories showed that epothilones and paclitaxel (paclitaxel) share similar mechanisms of action in stabilizing microtubule arrays as indicated by binding-displacement studies, substitution for paclitaxel in paclitaxel-dependent cell growth, and electron microscopic examinations. The present study examined cell growth-inhibitory effects in two rodent and three human tumor cell lines and their drug-resistant sublines. Although paclitaxel showed as much as 1, 970-fold cross-resistance to the sublines resistant to paclitaxel, adriamycin, vinblastine, or actinomycin D, most epothilones exhibit little or no cross-resistance. In multidrug-resistant CCRF-CEM/VBL100 cells, IC50 values for EpoA (1), EpoB (2), desoxyEpoA (3) (dEpoA), desoxyEpoB (4) (dEpoB), and paclitaxel were 0.02, 0.002, 0.012, 0.017, and 4.14 microM, respectively. In vivo studies, using i.p. administration, indicated that the parent, EpoB, was highly toxic to mice and showed little therapeutic effect when compared with a lead compound, dEpoB. More significantly, dEpoB (25-40 mg/kg, Q2Dx5, i.p.) showed far superior therapeutic effects and lower toxicity than paclitaxel, doxorubicin, camptothecin, or vinblastine (at maximal tolerated doses) in parallel experiments. For mammary adenocarcinoma xenografts resistant to adriamycin, MCF-7/Adr, superior therapeutic effects were obtained with dEpoB compared with paclitaxel when i.p. regimens were used. For ovarian adenocarcinoma xenografts, SK-OV-3, dEpoB (i.p.), and paclitaxel (i. v.) gave similar therapeutic effects. In nude mice bearing a human mammary carcinoma xenograft (MX-1), marked tumor regression and cures were obtained with dEpoB.

Discovery Through Total Synthesis-Epimerization at C7 in the CP Compounds: Is (7S)-CP-263,114 a Fermentation Product?

Sometimes a surprise can occur in a total synthesis. The preparative investigation of the title compound CP-263,114 and of CP-225,917 (1)-both natural products that were first isolated in 1997 by Pfizer-has shown that CP compounds of the 7R series can be converted into the 7S series (for example, 2); (7S)-CP-263,114 is itself apparently a fermentation product.

Insulin resistance, estimated by serum C-peptide level, is associated with reduced event-free survival for postmenopausal women in NCIC CTG MA.14 adjuvant breast cancer trial

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Background: NCIC CTG MA.14 is a randomized multi-centre trial of tamoxifen versus combined tamoxifen and octreotide LAR therapy in the adjuvant treatment of breast cancer in post-menopausal women. Planned secondary analyses included investigation of baseline metabolic factors that might influence survival. Laboratory and clinical studies indicate that insulin resistance is associated with adverse outcome in breast cancer. Insulin resistance elevates C-peptide levels. Methods: In MA.14, trial patients with stage I or II postmenopausal breast cancer were randomized from September, 1996 until July, 2000 to receive 20 mg tamoxifen PO daily for 5 years with/without the administration of the somatostatin analogue Octreotide LAR 90 mg depot injection monthly for 2 years. Event-free survival (EFS), the trial’s primary outcome measure, was defined as time from randomization to time of recurrence of primary disease, time of second malignancy or death due to any cause. We investigated the effect of baseline IGF-I, IGFBP-3, and C-peptide levels on EFS. Kaplan-Meier univariate and Cox step-wise multivariate regressions were performed with/without adjustment for the stratification factors of adjuvant chemotherapy, nodal status, and hormone receptor status, and included patient age (years) and tumour size (T-status). Results: These results are based on analysis of patient serum for the trial’s 667 patients. Median follow-up for those alive is 6.1 years; patients experienced 165 events. Higher C-peptide levels were associated with significantly worse EFS in adjusted, and unadjusted, univariate and multivariate analyses. Final efficacy analyses are expected within a few months. Updated analyses for the effects of baseline metabolic markers and body mass index on EFS will be presented. Conclusions: This is the largest data set, and the first clinical trial, linking higher serum C-peptide levels to adverse outcome in patients with early breast cancer. These results raise concern in the context of increasing population prevalence of insulin resistance. Potential novel adjuvant therapies exist as insulin resistance is modifiable.

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Magnetic resonance imaging used to assess patients with trigeminal neuralgia

To assess the value of magnetic resonance imaging in the evaluation of trigeminal neuralgia, 51 patients were studied by magnetic resonance imaging after a trigeminal protocol. Clinical and magnetic resonance imaging results were correlated. Seventeen (33%) nonvascular abnormalities and 27 (53%) vascular contacts or compressions of the trigeminal nerve were demonstrated. Of the patients younger than of 29 and 39 years of age, 100% and 45%, respectively, had a tumor or multiple sclerosis compared with 20% and 18% of those older than 40 and 60 years of age, respectively. One third of the patients with pain in more than one branch of the trigeminal nerve had tumors. On the basis of this study, magnetic resonance imaging may be useful in discovering underlying pathoses associated with trigeminal neuralgia if patients have failed to respond to an initial conservative treatment. The patients most likely to exhibit significant magnetic imaging resonance findings are young and with pain in more than one trigeminal branch.

The microtubule-stabilizing agents epothilones A and B and their desoxy-derivatives induce mitotic arrest and apoptosis in human prostate cancer cells

Epothilones are a new class of natural products that bind to tubulin and prevent the depolymerization of microtubules, although they have no structural similarity to paclitaxel. Taxanes are only marginally effective in the treatment of disseminated prostate cancer, although they may have useful activity when administered in combination with estramustine. Unlike paclitaxel, epothilones are not substrates for P-glycoprotein and are active in multidrug resistant cells. Epothilones A and B (EA, EB) have recently been synthesized in toto. In this report, we examine the effects of synthetic epothilones and their desoxy derivatives, as well as paclitaxel, on prostate cancer cell lines. EB was the most active of these compounds in tissue culture (IC(50): 50-75 pM), four to ten-fold more potent than paclitaxel. EA and the desoxyderivatives of EA and EB (dEA, dEB) were also active, but less potent than EB. Each of these compounds causes mitotic block followed by apoptotic cell death. The relative potencies for cell cycle arrest and cytotoxicity directly correlate with the ability of the drugs to bind microtubules, stabilize mitotic spindles and induce the formation of interphase microtubule bundles. Therefore, synthetic epothilones are potent inhibitors of prostate cancer cell lines and work in a fashion similar to paclitaxel. Recently, we showed that farnesyl transferase inhibitors sensitize tumor cells to paclitaxel-induced mitotic arrest. We now have extended these observations to show that paclitaxel and the epothilones synergize with FTI to arrest the growth of prostate cancer cells. Moreover, this occurs in DU145, a cell line that is not particularly sensitive to the FTI. The combination of FTI and epothilone represent a new potential clinical strategy for the treatment of advanced prostatic cancer.

Estrogen receptor beta-subtype selective tetrahydrofluorenones: use of a fused pyrazole as a phenol bioisostere

Synthesis of a series of fused pyrazole tetrahydrofluorenone analogs which are potent, ERbeta subtype selective ligands is described. Analogs possessing subnanomolar ERbeta binding, greater than 100-fold ERbeta-selectivity, and oral bioavailability are reported.

Exploring the interplay of barrier function and leukocyte recruitment in intestinal inflammation by targeting fucosyltransferase VII and trefoil factor 3

Intestinal mucosal integrity is dependent on epithelial function and a regulated immune response to injury. Fucosyltransferase VII (Fuc-TVII) is an essential enzyme required for the expression of the functional ligand for E- and P-selectin. Trefoil factor 3 (TFF3) is involved in both protecting the intestinal epithelium against injury as well as aiding in wound repair following injury. The aim of the present study was to assess the interplay between barrier function and leukocyte recruitment in intestinal inflammation. More specifically, we aimed to examine how targeted disruption of Fuc-TVII either in wild-type or TFF3(-/-) mice would alter their susceptibility to colonic injury. TFF3 and Fuc-TVII double-knockout mice (TFF3/Fuc-TVII(-/-) mice) were generated by mating TFF3(-/-) and Fuc-TVII(-/-) mice. Colitis was induced by administration of dextran sodium sulfate (DSS) (2.5% wt/vol) in the drinking water. Changes in baseline body weight, diarrhea, and fecal blood were assessed daily. Upon euthanasia, extents of colonic inflammation were assessed macroscopically, microscopically, and through quantification of myeloperoxidase (MPO) activity. Colonic lymphocyte subpopulations were assessed at 6 days after administration of DSS by flow cytometry and immunohistochemistry. No baseline intestinal inflammation was found in TFF3/Fuc-TVII(-/-), TFF3(-/-), Fuc-TVII(-/-), or wild-type mice. Loss of Fuc-TVII resulted in a reduction in disease severity whereas TFF3(-/-) mice were markedly more susceptible to DSS-induced colitis. Remarkably, the loss of Fuc-TVII in TFF3(-/-) mice markedly decreased the severity of DSS-induced colitis as evidenced by reduced weight loss, diarrhea, decreased colonic MPO levels and improved survival. Furthermore, the loss of TFF3 resulted in increased severity of spontaneous colitis in IL-2/beta-microglobulin-deficient mice. These studies highlight the importance of the interplay between factors involved in the innate immune response, mucosal barrier function, and genes involved in regulating leukocyte recruitment and other aspects of the immune response.

Inhibition of growth and increase of alkaline phosphatase activity in cultured human oral cancer cells by all-trans retinoic acid

In this study, the effects of all-trans retinoic acid (ATRA) on human oral cancer cells with regard to cell growth, the cell cycle, and alkaline phosphatase (ALP) activity were evaluated. Human oral cancer KB cells were treated with various concentrations of ATRA, and cell growth was then determined using the MTT viability assay. The cell-cycle distribution and ALP activity were analysed using a flow cytometer and chemical analyser, respectively. The KB cells were inhibited by ATRA at concentrations of 1-16 microM (1 microM, P<0.05; 2 microM, P<0.01; 4, 8 and 16 microM, P<0.001) in a dose-dependent manner. ATRA arrested KB cells in the G0/G1 phase. The ALP activity in KB cells was increased by ATRA. This is one of the first studies to focus on the expression of ALP in human head-and-neck carcinoma cells treated with retinoids. These findings suggest that the anti-tumour effects of ATRA on human oral cancer are associated with G0/G1 phase arrest and an increase in ALP activity.

Tetracycline-encapsulated P(3HB) microsphere-coated 45S5 Bioglass(®)-based scaffolds for bone tissue engineering

Bioglass(®)-based scaffolds for bone tissue engineering have been developed, which can also serve as carriers for drug delivery. For this, P(3HB) microspheres (PMSs) loaded with tetracycline were fabricated and immobilised on the scaffold surfaces by a modified slurry dipping technique. The sustained drug delivery ability in simulated body fluid was confirmed by using UV-Vis absorption spectroscopy measurements. The MTT assay using mouse fibroblast cells provided evidence that the tetracycline loaded microspheres produced in this study show limited cytotoxicity. The scaffolds developed in this work provide mechanical support, adequate 3D surface roughness, bioactivity and controlled drug delivery function, and are thus interesting candidates for bone tissue engineering applications.

Percentage of circulating CD8+ T lymphocytes is associated with albuminuria in type 2 diabetes mellitus

T lymphocytes have been demonstrated to play a role in the development of diabetic proteinuria. However, the alteration of circulating T lymphocytes has not been investigated in a type 2 diabetic cohort. A cross-sectional study was conducted in Peking University Aerospace Center Hospital. 510 participants were type 2 diabetes mellitus, 30-70 years of age. Patients with immune disease, medical conditions that affect immune function, infection, or end-organ damage were excluded. The percentage of circulating CD8+ T lymphocytes was significantly associated with albuminuria in the cohort. The impact of albuminuria to CD8+ T lymphocytes in a multivariate linear regression model was indicated by the B- coefficient (95% confidence interval) 1.812 (0.204-3.421, P=0.03). Our data first showed that the percentage of circulating CD8+ T cells is associated with albuminuria in type 2 diabetes mellitus, which may support the rationality of systemic inhibition of T lymphocytes in treating albuminuria in these patients.

Sonographic Assessment of Ceftriaxone-Associated Biliary Pseudolithiasis in Chinese Children

In this randomized, single-blind, case-controlled, prospective study, the incidence and outcome of ceftriaxone-associated biliary pseudolithiasis in Chinese children was evaluated via ultrasonography. A total of 108 children diagnosed with hepatobiliary infection or pneumonia were randomized to receive ceftriaxone or ceftazidime. Serial gallbladder sonograms were obtained on days 1, 5 − 7 and 10 − 14 of therapy. Gallstones were detected in 43.10% of patients in the ceftriaxone-treated group and in 2.00% of the ceftazidime-treated group. The incidence of pseudolithiasis was significantly higher in the ceftriaxone-treated than the ceftazidime-treated group. Biliary precipitation abnormalities appeared after 2 − 7 days of treatment. After gallstones were found, the drug was stopped and symptoms resolved within 1 − 2 days. This study suggests that the risk of ceftriaxone-associated biliary pseudolithiasis should be considered when treating Chinese children.

MicroRNA-203 inhibits tumour growth and metastasis through PDPN

OBJECTIVE

MicroRNAs play an important role in regulating hypopharyngeal cancer development. miR-203 has been previously shown to possess antitumour capabilities in many cancers, but not in hypopharyngeal cancer.

DESIGN

Using human normal and hypopharyngeal cancer specimens, we explored the expression levels of miR-203 in the two groups and further correlated them with different stages of cancer and lymph node metastasis.

SETTING AND PARTICIPANTS

Applying human pharynx FaDu cancer cells and lentiviral transduction technique, we investigated the effects of miR-203 on cancer cell viability, migration and invasion. Moreover, we studied the novel relationship between miR-203 and podoplanin (PDPN) in hypopharyngeal cancer.

RESULTS

The downregulated levels of miR-203 in human hypopharyngeal cancer tissues were associated with advanced cancer stages and lymph node metastasis. High levels of miR-203 inhibited cell viability, migration and invasion of hypopharyngeal cancer cells. Further studies suggested miR-203 directly targeted and inhibited PDPN expression. PDPN silencing suppresses hypopharyngeal cancer cell abilities. In addition, PDPN overexpression was able to reverse miR-203 inhibitory effects on cell viability, migration and invasion.

CONCLUSION

PDPN acts as an oncogene to promote hypopharyngeal cancer cell viability, migration and invasion. miR-203 directly targets PDPN to suppress its expression, thus exerting inhibitory effects on cancer metastasis.

Cerebral blood flow abnormalities in neuropsychiatric systemic lupus erythematosus

OBJECTIVE

To investigate the clinical characteristics, imaging changes and early diagnostic methods of neuropsychiatric systemic lupus erythematosus (NPSLE).

METHODS

Thirty-five SLE patients, of which 16 had overt neuropsychiatric symptoms, underwent examination for multiple autoantibodies, including anti-double-stranded DNA (anti-dsDNA) antibody, anti-nucleosome antibody, anti-cardiac-phospholipid antibody (aCL)-IgG, aCL-IgM, anti-β2-glycoprotein I antibody and anti-ribosomal P antibody, and the SLEDAI score of every patient was recorded. All patients further received neuropsychological tests, including the Mini-Mental State Examination, the Self-Rating Anxiety Scale and the Self-Rating Depression Scale. Imaging examination using 3D arterial spin labeling was performed on 3.0 T MRI scanners. After processing the 3D arterial spin labeling image, the cerebral blood flow map was obtained and the cerebral blood flow value was calculated.

RESULTS

The values of anti-dsDNA, anti-nucleosome antibody, aCL-IgG and anti-β2-glycoprotein I antibodies were significantly higher in the NPSLE group than those in the SLE group. The SLEDAI scores of the NPSLE group were significantly higher than those of the SLE group. There were no significant differences between the NPSLE group and the SLE group in the directional ability, memory, attention, numeracy, recall ability or language ability scores on the Mini-Mental State Examination scale. Furthermore, there were no symptoms of anxiety or depression in any of the patients, according to the Self-Rating Anxiety Scale and Self-Rating Depression Scale. In the 35 patients with SLE, decreases in blood perfusion were seen in some areas, and were unilateral and asymmetrically distributed. There was obvious asymmetry between sides in areas including the frontal lobe, temporal lobe, parietal lobe and occipital lobe. The incidence of perfusion decreases in frontal lobe in the NPSLE group was significantly higher than in the SLE group.

CONCLUSION

Neurological lesions in SLE patients can be detected by arterial spin labeling. Cerebral blood flow abnormalities may be helpful for the early diagnosis of neurological lesions in NPSLE.

On the inhibition of the RNA polymerase-catalysed synthesis of RNA by daunomycin. Interference of the inhibitor with elongation and pre-longation steps

The inhibition of the RNA polymerase-catalyzed synthesis of RNA by daunomycin was examined. Saturation binding of daunomycin to the template leads, as expected, to complete inhibition of RNA synthesis as a result of daunomycin interference with enzyme-template interactions. However at concentrations of the inhibitor below saturation formation of the enzyme-template complex remains remarkably undisturbed, while both the transformation of this complex to an elongating complex and the elongation of the nacsent RNA chains are substantially inhibited. Clearly, daunomycin interferes with a number of different substeps of RNA synthesis and inhibits the synthesis by different mechanisms depending on the amount of inhibitor bound to the template. Elucidation of the mechanism of inhibition at low daunomycin concentrations may be a prerequisite for a better understanding of the mechanism of the pharmacological action of the drug.

Mesiotemporal atrophy and hippocampal diffusivity distinguish amnestic from non-amnestic vascular cognitive impairment

Background and purpose

The role of clinical factors, cerebral infarcts and hippocampal damage in vascular cognitive impairment (VCI) subtypes remains unclear.

Methods

Non‐demented patients with carotid stenosis and recent transient ischemic attack/stroke had cognitive assessment and brain magnetic resonance imaging (MRI). Amnestic VCI was defined as memory impairment; non‐amnestic VCI was any other subdomain impairment. Associations of MRI metrics [log‐transformed total ischemic lesion load (log TILL), mesiotemporal atrophy (MTA) score, hippocampal mean diffusivity (hipMD)] with cognitive performance were assessed.

Results

A hundred and eight patients, 47 with amnestic VCI and 21 with non‐amnestic VCI, were assessed. A higher MTA (odds ratio 12.89, P = 0.001) and left hipMD (odds ratio 4.43, P = 0.003) contributed to amnestic VCI versus normal. Age‐adjusted fluency correlated with log TILL (P = 0.002). Age‐adjusted memory was associated with left hipMD (P = 0.001), MTA (P < 0.001) but not log TILL (P = 0.14). Left hipMD, MTA and smoking showed classification potential between amnestic VCI versus normal (area 0.859, P < 0.001).

Conclusions

Neuroimaging assists stratification in amnestic VCI characterized by hippocampal changes and in non‐amnestic VCI by higher ischemic burden. MTA and hippocampal diffusivity show diagnostic biomarker potential.

Noninvasive prenatal diagnosis for pregnancies at risk for β-thalassaemia: a retrospective study

OBJECTIVE

To evaluate the clinical feasibility of noninvasive prenatal diagnosis (NIPD) for β-thalassaemia using circulating single molecule amplification and re-sequencing technology (cSMART).

DESIGN

Through carrier screening, 102 pregnant Chinese couples carrying pathogenic HBB gene variants were recruited to the study. Pregnancies were managed using traditional invasive prenatal diagnosis (IPD). Retrospectively, we evaluated the archived pregnancy plasma DNA by NIPD to evaluate the performance of our cSMART assay for fetal genotyping.

SETTING

Chinese prenatal diagnostic centres specialising in thalassaemia testing.

POPULATION

Chinese carrier couples at high genetic risk for β-thalassaemia.

METHODS

Fetal cell sampling was performed by amniocentesis and HBB genotypes were determined by reverse dot blot. NIPD was performed by a newly designed HBB cSMART assay and fetal genotypes were called by measuring the allelic ratios in the maternal cell-free DNA.

MAIN OUTCOME MEASURES

Concordance of HBB fetal genotyping between IPD and NIPD and the sensitivity and specificity of NIPD.

RESULTS

Invasive prenatal diagnosis identified 29 affected homozygotes or compound heterozygotes, 54 heterozygotes and 19 normal homozygotes. Compared with IPD results, 99 of 102 fetuses (97%) were correctly genotyped by our NIPD assay. Two of three discordant samples were false positives and the other sample involved an incorrect call of a heterozygote carrier as a homozygote normal. Overall, the sensitivity and specificity of our NIPD assay was 100% (95% CI 88.06-100.00%) and 97.26% (95% CI 90.45-99.67%), respectively.

CONCLUSIONS

This study demonstrates that our cSMART-based NIPD assay for β-thalassaemia has potential clinical utility as an alternative to IPD for pregnant HBB carrier couples.

TWEETABLE ABSTRACT

A new noninvasive test for pregnancies at risk for β-thalassaemia.

Are Linear Measurements of the Nucleus Basalis of Meynert Suitable as a Diagnostic Biomarker in Mild Cognitive Impairment and Alzheimer Disease?

BACKGROUND AND PURPOSE

Cell loss within the nucleus basalis of Meynert is an early event in Alzheimer disease. The thickness of the nucleus basalis of Meynert (NBM) can be measured on structural MR imaging. We investigated NBM thickness in relation to cognitive state and biochemical markers.

MATERIALS AND METHODS

Mean bilateral nucleus basalis of Meynert thickness was measured on coronal T1-weighted MR imaging scans from the Alzheimer's Disease Neuroimaging Initiative dataset. Three hundred and fifteen scans (80 controls, 79 cases of early mild cognitive impairment, 77 cases of late mild cognitive impairment and 79 cases of Alzheimer disease) were assessed. Alzheimer's Disease Assessment Scale-Cognitive scores, CSF tau, and amyloid quantification were extracted. Group differences in NBM thickness, their correlates and measurement reliability were assessed.

RESULTS

Mean NBM thickness ± SD progressively declined from 2.9 ± 0.3, 2.5 ± 0.3, and 2.3 ± 0.3 to 1.8 ± 0.4 mm in healthy controls, patients with early mild cognitive impairment, late mild cognitive impairment and Alzheimer disease respectively (P < .001). NBM thickness was negatively correlated with Alzheimer's Disease Assessment Scale-Cognitive scores (r = -0.53, P < .001) and weakly positively correlated with CSF amyloid (r = 0.250, P < .001) respectively. No association with CSF tau was found. NBM thickness showed excellent diagnostic accuracy to differentiate Alzheimer disease (area under the curve, 0.986) and late mild cognitive impairment from controls (area under the curve, 0.936) with excellent sensitivity, but lower specificity 66.7%. Intra- and interrater reliability for measurements was 0.66 and 0.47 (P < .001).

CONCLUSIONS

There is progressive NBM thinning across the aging-dementia spectrum, which correlates with cognitive decline and CSF markers of amyloid-β pathology. We show high diagnostic accuracy but limited reliability, representing an area for future improvement. NBM thickness is a promising, readily available MR imaging biomarker of Alzheimer disease warranting diagnostic-accuracy testing in clinical practice.

Large-scale network dysfunction in vascular cognitive disorder supports connectional diaschisis in advanced arteriosclerosis

BACKGROUND AND PURPOSE

The interrelation of cognitive performance, cerebrovascular damage and brain functional connectivity (FC) in advanced arteriosclerosis remains unclear. Our aim was to investigate the associations between FC, white matter damage and cognitive impairment in carotid artery disease.

METHODS

Seventy-one participants with a recent cerebrovascular event and with written informed consent underwent resting-state functional magnetic resonance imaging and the Addenbrooke's Cognitive Examination - Revised (ACE-R). Network and inter-hemispheric FC metrics were compared between cognitively normal and impaired subjects, and interrelated with cognition. In order to explore the nature of FC changes, their associations with microstructural damage of related white matter tracts and cognitive performance were investigated, followed by mediation analysis.

RESULTS

Participants with global cognitive impairment showed reduced FC compared to the cognitively intact subjects within the central executive network (CEN), and between hemispheres. Patients with executive dysfunction had decreased CEN FC whilst patients with memory loss demonstrated low FC in both the CEN and the default mode network (DMN). Global performance correlated with connectivity metrics of the CEN hub with DMN nodes, and between hemispheres. Cingulum mean diffusivity (MD) was negatively correlated with ACE-R and CEN-DMN FC. The cingulum MD-cognition association was partially mediated by CEN-DMN FC.

CONCLUSIONS

Long-range functional disconnection of the CEN with DMN nodes is the main feature of cognitive impairment in elderly subjects with symptomatic carotid artery disease. Our findings provide further support for the connectional diaschisis concept of vascular cognitive disorder, and highlight a mediation role of functional disconnection to explain associations between microstructural white matter tract damage and cognitive impairment.

Competing causes of death in NCIC CTG MA.17, a placebo-controlled trial of letrozole as extended adjuvant therapy for breast cancer patients

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Background: Risk of death from other malignancies (OM) and other causes (OC) than breast cancer (BC) increases with age. Effects of baseline factors on type of death were assessed with competing risks analyses. Methods: In NCIC CTG MA.17, 5,187 women free of recurrent breast cancer after 5 years of tamoxifen were randomized to letrozole (L, 2,593 women) or placebo (P, 2,594 women). The primary endpoint was disease free survival (DFS), and secondary, overall survival (OS). Follow-up was to October 9, 2005: median 3.9 years, range <0.1 to 7.0 years. Effects of competing risks were examined for endpoints of BC, OM, and OC for 11 baseline trial factors: treatment, age, menopausal status, duration of prior tamoxifen, adjuvant radiotherapy, bone fracture, osteoporosis, cardiovascular disease, hormone receptor status, nodal status, adjuvant chemotherapy. Lagakos’ hierarchical method (Lagakos, Appl. Statist. 1978; 27:235–241) was used to test for differential effects of baseline factors on type of death (BC, OM, OC). Results: Rate of censoring was 97.8%, with 256 deaths (BC, 102; OM, 50; OC, 100; unknown, 4). Non-breast cancer deaths accounted for 60% of known deaths; 72%, for those ≥70 years; and 48%, for those <70 years. Two baseline factors differentially affected type of death. Women with cardiovascular disease were more likely to die from OC (p=0.02), while those with osteoporosis were more likely to die of OM (p=0.03). Age and nodal status had directionally similar effects. Older women had shorter survival from all 3 causes of death (p=0.01). Lymph node positivity was associated with worse survival (p=0.003). Conclusions: Extended L provides similar proportional benefit in improving DFS for all ages of women (Muss ref abstract SABCS 2006). However, the magnitude of competing non-breast cancer, and non-treatment related, causes of death needs to be considered more frequently, since with early detection and improved therapies, breast cancer patients may increasingly be expected to survive their disease to die from another cause. The novel association between baseline osteoporosis and other malignancies is being explored quantitatively.

No significant financial relationships to disclose.

Hybrid Exercise Program Enhances Physical Fitness and Reverses Frailty in Older Adults: Insights and Predictions from Machine Learning

PURPOSE

The declining physical condition of the older adults is a pressing issue. Wu Qin Xi exercise, despite being low-intensity, is highly effective among older adults. Inspired by its characteristics, we designed a new exercise program for frail older adults, combining strength, endurance, and Wu Qin Xi. Furthermore, we employed machine learning to predict whether frailty can be reversed in older adults after the intervention.

METHODS

A total of 181 community-dwelling frail older adults aged 65 years or older participated in this single-center, randomized controlled study, with 54.7% (n=99) being female. The study assessed the effectiveness of several exercise modalities in reversing frailty. The Fried's frailty criterion was used to assess the degree of frailty of the subjects. Participants were assigned a three-digit code 001-163 and randomly assigned (1:1:1) by computer to three different groups based on the study participant number: the Wu Qin Xi group (WQX), the strength exercise mixed with endurance exercise training group (SE), and the WQXSE hybrid exercise group incorporated the above two. Body composition and frailty-related physical fitness factors were measured before and after a 24-week intervention. The measurements included Body height, Body mass, Timed Up and Go Test (TUGT), grip strength assessment (GS), 6min walk test (6 min WT), and 10 m maximum walk speed (10 m MWS). Data were analyzed using repeated measures ANOVA to determine group and time interaction effects and machine learning models were used to predict program effectiveness.

RESULTS

A total of 163 participants completed the study, with 53.9% (n=88) of them being female. The two items, 10 m maximum walking speed (10 m MWS) and grip strength, were significantly affected by the interaction of group and time. Compared to the other two groups, the WQXSE group showed the most improvement in the item 10 m MWS. In addition, following 24 weeks of training, 68 (41.7%) of the initially frail older adults had reversed their frailty status. Among them, 19 (36.5%) were in the WQX group, 24 (44.4%) were in the WQXSE group, and 25 (43.9%) were in the SE group. The stacking model exhibited superior performance when compared to other algorithms.

CONCLUSION

A hybrid exercise regimen comprising the Wu Qin Xi routine and exercises focused on both strength and endurance holds the potential to yield greater improvements in the physical fitness of older adults, as well as reducing frailty. Leveraging a stacking model, it is possible to forecast the likelihood of older adults successfully reversing their frailty status following participation in a prevention exercise program.