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1.
Microorganisms ; 11(9)2023 Sep 09.
Article En | MEDLINE | ID: mdl-37764105

Allelopathic chemicals facilitated by the direct contact of macroalgae with corals are potentially an important mechanism mediating coral-macroalgal interactions, but only a few studies have explored their impacts on coral health and microbiomes and the coral's ability to recover. We conducted a field experiment on an equatorial urbanized reef to assess the allelopathic effects of four macroalgal species (Bryopsis sp., Endosiphonia horrida, Hypnea pannosa and Lobophora challengeriae) on the health and microbiomes of three coral species (Merulina ampliata, Montipora stellata and Pocillopora acuta). Following 24 h of exposure, crude extracts of all four macroalgal species caused significant coral tissue bleaching and reduction in effective quantum yield. The corals were able to recover within 72 h of the removal of extracts, except those that were exposed to L. challengeriae. While some macroalgal extracts caused an increase in the alpha diversity of coral microbiomes, there were no significant differences in the composition and variability of coral microbiomes between controls and macroalgal extracts at each sampling time point. Nevertheless, DESeq2 differential abundance analyses showed species-specific responses of coral microbiomes. Overall, our findings provide insights on the limited effect of chemically mediated interactions with macroalgae on coral microbiomes and the capacity of corals to recover quickly from the macroalgal chemicals.

2.
J Clin Endocrinol Metab ; 103(9): 3340-3349, 2018 09 01.
Article En | MEDLINE | ID: mdl-29982545

Context: Measurement of areal bone mineral density (aBMD) by dual-energy x-ray absorptiometry (DXA) was able to predict fracture risk. High-resolution peripheral quantitative computed tomography (HR-pQCT) yields additional information about volumetric bone mineral density (vBMD), microarchitecture, and strength that may increase our understanding of fracture susceptibility. Objective: To ascertain whether vBMD, microarchitecture, and estimated bone strength derived from HR-pQCT can discriminate vertebral fractures in patients with glucocorticoid-induced osteoporosis (GIOP) independent of aBMD. Design: A cross-sectional case-control study. Setting: Seven regional hospitals in Hong Kong. Patients: A total of 110 patients on long-term glucocorticoids with vertebral fracture, determined radiographically, and 110 patients on long-term glucocorticoids without fracture. Main Outcome Measures: We assessed vBMD, microarchitecture, and bone strength; aBMD; and fracture risk assessment tool (FRAX). Results: Patients with vertebral fracture had lower total vBMD and a thinner cortex at the distal tibia after adjustment for age, sex, and aBMD or FRAX. In the antiresorptive treatment-naive subgroup, patients with vertebral fracture also had lower total vBMD at both the distal radius and the tibia after adjustment for covariates. Lower total vBMD and a thinner cortex were also noticed in the nonosteoporotic or FRAX score of <10% subgroups with vertebral fracture and were also associated with increasing prevalence of vertebral fracture. Conclusion: Patients with GIOP and vertebral fracture have a significant reduction in total vBMD and cortical thinning independent of aBMD and FRAX. These changes may help identify high-risk patients in the subgroups currently considered to have low fracture risk as assessed by DXA or FRAX.


Bone Density , Glucocorticoids/adverse effects , Osteoporosis/physiopathology , Spinal Fractures/etiology , Tomography, X-Ray Computed/methods , Absorptiometry, Photon , Adult , Aged , Case-Control Studies , Cortical Bone/diagnostic imaging , Cortical Bone/physiopathology , Cross-Sectional Studies , Female , Hong Kong , Humans , Male , Middle Aged , Osteoporosis/chemically induced , Osteoporosis/complications , Prevalence , Radius/diagnostic imaging , Radius/physiopathology , Risk Factors , Spinal Fractures/epidemiology , Tibia/diagnostic imaging , Tibia/physiopathology , Time Factors
3.
Cardiovasc Intervent Radiol ; 39(8): 1136-43, 2016 Aug.
Article En | MEDLINE | ID: mdl-27154017

PURPOSE: To evaluate the microvascular distribution of lipiodol-ethanol, the histological change of the tumor lesion, and the status of tumor involution over time in hepatocellular carcinoma (HCC) following transarterial ethanol ablation (TEA), in lesions that showed CT evidence of complete tumor response. MATERIALS AND METHODS: Patients with unresectable HCC were treated (183 patients, 242 lesions) with TEA using lipiodol-ethanol mixture (LEM) mixed in 2:1 ratio by volume and followed with CT at 3-month intervals for a median of 14.1 months. Liver tumors (n = 131) that showed CT evidence of complete tumor response, defined as the absence of any enhancing tumor throughout the follow-up period, were included. The surgical specimens of five patients who subsequently received partial hepatectomy were available for histological assessment. The microvascular distribution of LEM and the degree of tumor necrosis were analyzed. Tumor involution over time was assessed with CT in lesions that showed complete response. RESULTS: Lipid stain revealed lipiodol infiltration throughout arterioles, intratumoral sinusoidal spaces, tumor capsule, and peritumoral portal venules. Complete tumor necrosis (100 %) occurred in all 5 surgical specimens. The median (IQR) percentage tumor volume compared to baseline volumes at 12, 36, and 60 months was 32 % (23.5-52.5 %), 22 % (8-31 %), and 13.5 % (6-21.5 %), respectively. CONCLUSION: Intrahepatic HCC lesion that showed CT evidence of complete tumor response following TEA is associated with histological evidence of LEM infiltration throughout the intratumoral and peritumoral vasculature and complete tumor necrosis, as well as sustained reduction in tumor volume over time.


Carcinoma, Hepatocellular/therapy , Chemoembolization, Therapeutic/methods , Liver Neoplasms/therapy , Aged , Carcinoma, Hepatocellular/diagnostic imaging , Ethanol/administration & dosage , Ethiodized Oil/administration & dosage , Female , Humans , Liver/diagnostic imaging , Liver Neoplasms/diagnostic imaging , Male , Middle Aged , Prospective Studies , Tomography, X-Ray Computed , Treatment Outcome
4.
J Vasc Interv Radiol ; 27(5): 639-49, 2016 May.
Article En | MEDLINE | ID: mdl-26803574

PURPOSE: To evaluate survival, tumor response, and treatment toxicity of transarterial ethanol ablation (TEA) in patients with unresectable hepatocellular carcinoma (HCC). MATERIALS AND METHODS: This prospective study involved 186 patients (146 men and 40 women; median age, 65 y [interquartile range, 57-72.3 y]). Of 186 patients, 146 (78.5%) were hepatitis B virus carriers, 18 (9.7%) were hepatitis C virus carriers, 82 (44.1%) had tumors ≥ 5 cm, and 43 (23.1%) had multifocal tumors. Overall survival (OS), complete response (CR) by European Association for the Study of the Liver criteria, time to progression (TTP), progression-free survival (PFS), and treatment toxicities were evaluated. Univariate and multivariate analyses for prognostic factors of OS were performed. RESULTS: Median OS was 25.7 months (95% confidence interval [CI], 20.9-30.5) and varied significantly between Child-Pugh A and B (28.7 mo vs 13.4 mo, P < .001), and Barcelona Clinic Liver Cancer A and B or C (37.1 mo vs 17.7 mo, P = .001). Prognostic factors for longer OS were solitary tumor, tumor size < 5 cm, > 1 treatments, and CR of all tumors at 6 months. TTP was 9.1 months (95% CI, 6.9-11.3). PFS was 8.4 months (95% CI, 7.1-9.7). CR occurred in 69.1% (159/230) of lesions and 48.9% (88/180) of patients at 6 months. Any one symptom of the postembolization syndrome of grade 2 severity occurred in < 22% (41/186) of patients. No treatment-related hepatitis or death occurred within 30 days. Transient respiratory decompensation occurred in three patients (1.6% [3/186]), and alcoholic intoxication occurred in one patient (0.5% [1/186]). CONCLUSIONS: TEA appears to be safe and effective for local control of HCC.


Ablation Techniques , Carcinoma, Hepatocellular/surgery , Ethanol/administration & dosage , Hepatic Artery , Liver Neoplasms/surgery , Ablation Techniques/adverse effects , Ablation Techniques/mortality , Aged , Angiography, Digital Subtraction , Carcinoma, Hepatocellular/diagnostic imaging , Carcinoma, Hepatocellular/mortality , Carcinoma, Hepatocellular/pathology , Disease Progression , Disease-Free Survival , Ethanol/adverse effects , Female , Hepatic Artery/diagnostic imaging , Humans , Infusions, Intra-Arterial , Kaplan-Meier Estimate , Liver Neoplasms/diagnostic imaging , Liver Neoplasms/mortality , Liver Neoplasms/pathology , Male , Middle Aged , Multivariate Analysis , Proportional Hazards Models , Prospective Studies , Risk Factors , Time Factors , Treatment Outcome
5.
Hong Kong Med J ; 18(3): 221-5, 2012 Jun.
Article En | MEDLINE | ID: mdl-22665686

OBJECTIVES: To investigate the frequency of pseudoprogression of glioblastoma in Chinese patients receiving concomitant chemoradiotherapy and investigate its association with pseudoprogression and tumour molecular marker O(6)-methylguanine-DNA methyltransferase promoter methylation status. DESIGN: Case series with internal comparisons. SETTING: University teaching hospital, Hong Kong. PATIENTS: Patients with glioblastoma treated with concomitant chemoradiotherapy during April 2005 to June 2010 were reviewed. Magnetic resonance imaging brain scans, pre- and post-concomitant chemoradiotherapy and 3-monthly thereafter were reviewed by an independent neuroradiologist according to Macdonald's criteria. Relevant patient information (clinical condition, performance score, development of new neurological deficits, use of steroids, and survival) was retrieved. For each patient, O(6)-methylguanine-DNA methyltransferase methylation status was investigated with genomic DNA from formalin-fixed or paraffin-embedded sections of tumour tissues by methylation-specific polymerase chain reaction. RESULTS: During the study period, 28 primary glioblastoma patients underwent concomitant chemoradiotherapy. The mean age of the patients was 48 (range, 16-71) years. Thirteen patients (13/28, 46%) developed early radiological progression of the tumour after completion of concomitant chemoradiotherapy, of whom five (39%) were subsequently found to have had pseudoprogression. Patients with pseudoprogression showed a trend towards longer survival (22 months in pseudoprogression vs 17 months in all others vs 11 months in those with genuine progression). Among the 27 patients tested for O(6)-methylguanine-DNA methyltransferase promoter status, 12 (44%) were methylated. Two (2/12, 17%) in the methylated group had pseudoprogression, while three (3/15, 20%) in the unmethylated group had pseudoprogression. CONCLUSIONS: Nearly half of all patients (46%) developed early radiological progression (within 3 months of completing concomitant chemoradiotherapy). Moreover, about one in three of such patients had pseudoprogression. Pseudoprogression is an important clinical condition to be aware of to prevent premature termination of an effective treatment.


Antineoplastic Agents, Alkylating/therapeutic use , Brain Neoplasms/therapy , DNA Modification Methylases/genetics , Glioblastoma/therapy , Glioma/therapy , O(6)-Methylguanine-DNA Methyltransferase/genetics , Adolescent , Adult , Aged , Antineoplastic Agents, Alkylating/adverse effects , Asian People , Biomarkers, Tumor , Brain Neoplasms/genetics , Chemoradiotherapy , DNA Methylation , Disease Progression , Glioblastoma/genetics , Glioma/genetics , Humans , Magnetic Resonance Imaging , Middle Aged , Treatment Outcome , Young Adult
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