ABSTRACT
The purpose of the study was to determine whether neuromuscular electrical stimulation resistance training (NMES-RT)-evoked muscle hypertrophy is accompanied by increased VÌo2 peak, ventilatory efficiency, and mitochondrial respiration in individuals with chronic spinal cord injury (SCI). Thirty-three men and women with chronic, predominantly traumatic SCI were randomized to either NMES-RT (n = 20) or passive movement training (PMT; n = 13). Functional electrical stimulation-lower extremity cycling (FES-LEC) was used to test the leg VÌo2 peak, VÌE/VÌco2 ratio, and substrate utilization pre- and postintervention. Magnetic resonance imaging was used to measure muscle cross-sectional area (CSA). Finally, muscle biopsy was performed to measure mitochondrial complexes and respiration. The NMES-RT group showed a significant increase in postintervention VÌo2 peak compared with baseline (ΔVÌo2 = 14%, P < 0.01) with no changes in the PMT group (ΔVÌo2 = 1.6%, P = 0.47). Similarly, thigh (ΔCSAthigh = 19%) and knee extensor (ΔCSAknee = 30.4%, P < 0.01) CSAs increased following NMES-RT but not after PMT. The changes in thigh and knee extensor muscle CSAs were positively related with the change in VÌo2 peak. Neither NMES-RT nor PMT changed mitochondrial complex tissue levels; however, changes in peak VÌo2 were related to complex I. In conclusion, in persons with SCI, NMES-RT-induced skeletal muscle hypertrophy was accompanied by increased peak VÌo2 consumption which may partially be explained by enhanced activity of mitochondrial complex I.NEW & NOTEWORTHY Leg oxygen uptake (VÌo2) and ventilatory efficiency (VÌE/VÌco2 ratio) were measured during functional electrical stimulation cycling testing following 12-16 wk of either electrically evoked resistance training or passive movement training, and the respiration of mitochondrial complexes. Resistance training increased thigh muscle area and leg VÌo2 peak but decreased VÌE/VÌco2 ratio without changes in mitochondrial complex levels. Leg VÌo2 peak was associated with muscle hypertrophy and mitochondrial respiration of complex I following training.
Subject(s)
Electric Stimulation Therapy , Resistance Training , Spinal Cord Injuries , Electric Stimulation , Female , Humans , Male , Muscle, Skeletal , Oxygen , Spinal Cord Injuries/therapyABSTRACT
Aims: The aim of the study was to analyze the epidemiology of Acinetobacter baumannii and investigate the genetic characteristics of carbapenem-resistant A. baumannii (CRAB) isolates isolated from blood cultures in a regional hospital in Hong Kong. Results: Twenty blood culture isolates were collected from a regional hospital in Hong Kong from 2014 to 2017. Twenty isolates were grouped into five existing sequence types (STs) and five new STs within the following prevalence: ST195 was predominant with a prevalence of 45% (n = 9), followed by ST373 and ST447 (10%; n = 2 each), and ST176 and ST345 (5%; n = 1 each). Resistance to carbapenem antibiotics was 55% (n = 11). Six carbapenem-resistant isolates harbored blaOXA-23 genes and ISAba1 mobile elements. Polymerase chain reaction confirmed that ISAba1 is located upstream to the blaOXA-23 genes, suggesting an association between ISAba1 and blaOXA-23 genes with carbapenem resistance. Conclusion: This study is the first to report the emergence of CRAB ST195 harboring blaOXA-23 in Hong Kong.
Subject(s)
Acinetobacter Infections/microbiology , Acinetobacter baumannii/genetics , Acinetobacter baumannii/isolation & purification , Bacterial Proteins/genetics , Carbapenems/therapeutic use , Drug Resistance, Bacterial/genetics , beta-Lactamases/genetics , Acinetobacter Infections/drug therapy , Anti-Bacterial Agents/therapeutic use , Bacteremia/microbiology , Cross Infection/drug therapy , Cross Infection/microbiology , Cross-Sectional Studies , Hong Kong , Hospitals , Humans , Microbial Sensitivity Tests/methods , Molecular Epidemiology , Multilocus Sequence Typing/methods , Retrospective StudiesABSTRACT
Many drugs, hormones, components of herbal medicines, environmental pesticides and toxins are Solute Carrier family 22 (SLC22) substrates. The last twenty years has seen great progress in determining SLC22 tissue expression profiles, membrane localization, energetics, substrate profiles and biopharmaceutical significance. However, much still remains to be answered in terms of SLC22 family member's roles in 'normal' physiology as compared to pathophysiological states, as well as in drug interactions that impact pharmacokinetics, efficacy and toxicity. This review begins with a brief synopsis of SLC22 family discovery, function and tissue expression. Subsequent sections provide examples establishing a role for SLC22 transporters in food-drug, herbal supplement-drug, endogenous substrate-drug and drug-drug interactions.
Subject(s)
Drug Interactions , Food-Drug Interactions , Organic Cation Transport Proteins/metabolism , Animals , Dietary Supplements/adverse effects , Dietary Supplements/analysis , Humans , Multigene Family , Organic Cation Transport Proteins/geneticsABSTRACT
Radiation therapy (RT) the front-line treatment after surgery for early breast cancer patients is associated with acute skin toxicities in at least 40% of treated patients. Monocyte-derived macrophages are polarized into functionally distinct (M1 or M2) activated phenotypes at injury sites by specific systemic cytokines known to play a key role in the transition between damage and repair in irradiated tissues. The role of M1 and M2 macrophages in RT-induced acute skin toxicities remains to be defined. We investigated the potential value of M1 and M2 macrophages as predictive factors of RT-induced skin toxicities in early breast cancer patients treated with adjuvant RT after lumpectomy. Blood samples collected from patients enrolled in a prospective clinical study (n = 49) were analyzed at baseline and after the first delivered 2Gy RT dose. We designed an ex vivo culture system to differentiate patient blood monocytes into macrophages and treated them with M1 or M2-inducing cytokines before quantitative analysis of their "M1/M2" activation markers, iNOS, Arg1, and TGFß1. Statistical analysis was performed to correlate experimental data to clinical assessment of acute skin toxicity using Common Toxicity Criteria (CTC) grade for objective evaluation of skin reactions. Increased ARG1 mRNA significantly correlated with higher grades of erythema, moist desquamation, and CTC grade. Multivariate analysis revealed that increased ARG1 expression in macrophages after a single RT dose was an independent prognostic factor of erythema (p = 0 .032), moist desquamation (p = 0 .027), and CTC grade (p = 0 .056). Interestingly, multivariate analysis of ARG1 mRNA expression in macrophages stimulated with IL-4 also revealed independent prognostic value for predicting acute RT-induced toxicity factors, erythema (p = 0 .069), moist desquamation (p = 0 .037), and CTC grade (p = 0 .046). To conclude, our findings underline for the first time the biological significance of increased ARG1 mRNA levels as an early independent predictive biomarker of RT-induced acute skin toxicities.
Subject(s)
Arginase/metabolism , Breast Neoplasms/radiotherapy , Carcinoma, Ductal, Breast/enzymology , Macrophages/enzymology , Radiation Injuries/enzymology , Skin Diseases/enzymology , Arginase/genetics , Breast Neoplasms/enzymology , Carcinoma, Ductal, Breast/radiotherapy , Cells, Cultured , Female , Humans , Middle Aged , Nitric Oxide Synthase Type II/metabolism , Prognosis , Transforming Growth Factor beta/metabolismABSTRACT
BACKGROUND & AIMS: The human equilibrative nucleoside transporter (hENT1) protein transports gemcitabine into cells. Small retrospective studies in pancreatic cancer suggest that levels of hENT1 protein or messenger RNA may have prognostic value. We studied the predictive value of hENT1 levels in a cohort of pancreatic adenocarcinoma patients from the large prospective randomized adjuvant treatment trial RTOG9704. METHODS: In RTOG9704, 538 patients were assigned randomly, after surgical resection, to groups that were given either gemcitabine or 5-fluorouracil (5-FU). Immunohistochemistry for hENT1 was performed on a tissue microarray of 229 resected pancreatic tumors from RTOG9704 and scored as having no staining, low staining, or high staining. Associations between hENT1 protein and treatment outcome were analyzed by unconditional logistic regression analysis using the chi-square test and the Cox proportional hazards model. RESULTS: HENT1 expression was associated with overall and disease-free survival in a univariate (hazard ratio [HR], 0.51; 95% confidence interval [CI], 0.29-0.91; P= .02; and HR, 0.57; 95% CI, 0.32-1.00; P= .05) and multivariate model in the group given gemcitabine (HR, 0.40; 95% CI, 0.22-0.75; P= .004; and HR, 0.39; 95% CI, 0.21-0.73; P= .003). hENT1 expression was not associated with survival in the group given 5-FU. CONCLUSIONS: In this prospective randomized trial, hENT1 protein expression was associated with increased overall survival and disease-free survival in pancreatic cancer patients who received gemcitabine, but not in those who received 5-FU. These findings are supported by preclinical data; the gemcitabine transporter hENT1 is therefore a molecular and mechanistically relevant predictive marker of benefit from gemcitabine in patients with resected pancreatic cancer.
Subject(s)
Antimetabolites, Antineoplastic/therapeutic use , Deoxycytidine/analogs & derivatives , Equilibrative Nucleoside Transporter 1/analysis , Pancreatic Neoplasms/drug therapy , Adult , Aged , Deoxycytidine/adverse effects , Deoxycytidine/therapeutic use , Equilibrative Nucleoside Transporter 1/genetics , Female , Fluorouracil/therapeutic use , Humans , Male , Middle Aged , Multivariate Analysis , Pancreatic Neoplasms/chemistry , Pancreatic Neoplasms/mortality , RNA, Messenger/analysis , Treatment Outcome , GemcitabineABSTRACT
Curcumin is recognized as a potential chemotherapeutic agent against a variety of tumors. However, the clinical application of curcumin is hindered due to its poor water solubility and fast degradation. The objective of this study was to investigate amphiphilic block copolymer micelles of poly(ethylene oxide)-b-poly(epsilon-caprolactone) (PEO-PCL) as vehicles for the solubilization, stabilization, and controlled delivery of curcumin. Curcumin-loaded PEO-PCL micelles were prepared by a cosolvent evaporation technique. PEO-PCL micelles were able to solubilize curcumin effectively, protect the encapsulated curcumin from hydrolytical degradation in physiological matrix, and control the release of curcumin over a few days. The characteristics of resultant micelles were found to depend on the polymerization degrees of epsilon-caprolactone. Among different PEO-PCL micelles, PEO(5000)-PCL(24500) was the most efficient in solubilizing curcumin while PEO(5000)-PCL(13000) was the best carrier in reducing its release rate. PEO-PCL micelle-encapsulated curcumin retained its cytotoxicity in B16-F10, a mouse melanoma cell line, and SP-53, Mino, and JeKo-1 human mantle cell lymphoma cell lines. These results demonstrated the potential of PEO-PCL micelles as an injectable formulation for efficient solubilization, stabilization, and controlled delivery of curcumin.
Subject(s)
Curcumin/administration & dosage , Delayed-Action Preparations/chemistry , Lactones/therapeutic use , Polyethylene Glycols/therapeutic use , Animals , Antineoplastic Agents , Cell Line, Tumor , Cell Survival/drug effects , Curcumin/pharmacology , Drug Stability , Humans , Mice , Micelles , SolubilityABSTRACT
SALL4, a human homolog to Drosophila spalt, is a novel zinc finger transcriptional factor essential for development. We cloned SALL4 and its isoforms (SALL4A and SALL4B). Through immunohistochemistry and real-time reverse-transcription-polymerase chain reaction (RT-PCR), we demonstrated that SALL4 was constitutively expressed in human primary acute myeloid leukemia (AML, n = 81), and directly tested the leukemogenic potential of constitutive expression of SALL4 in a murine model. SALL4B transgenic mice developed myelodysplastic syndrome (MDS)-like features and subsequently AML that was transplantable. Increased apoptosis associated with dysmyelopoiesis was evident in transgenic mouse marrow and colony-formation (CFU) assays. Both isoforms could bind to beta-catenin and synergistically enhanced the Wnt/beta-catenin signaling pathway. Our data suggest that the constitutive expression of SALL4 causes MDS/AML, most likely through the Wnt/beta-catenin pathway. Our murine model provides a useful platform to study human MDS/AML transformation, as well as the Wnt/beta-catenin pathway's role in the pathogenesis of leukemia stem cells.