TGF-β downstream of Smad3 and MAPK signaling antagonistically regulate the viability and partial epithelial-mesenchymal transition of liver progenitor cells

BACKGROUND

Liver progenitor cells (LPCs) are a subpopulation of cells that contribute to liver regeneration, fibrosis and liver cancer initiation under different circumstances.

RESULTS

By performing adenoviral-mediated transfection, CCK-8 analyses, F-actin staining, transwell analyses, luciferase reporter analyses and Western blotting, we observed that TGF-β promoted cytostasis and partial epithelial-mesenchymal transition (EMT) in LPCs. In addition, we confirmed that TGF-β activated the Smad and MAPK pathways, including the Erk, JNK and p38 MAPK signaling pathways, and revealed that TGFβ-Smad signaling induced growth inhibition and partial EMT, whereas TGFβ-MAPK signaling had the opposite effects on LPCs. We further found that the activity of Smad and MAPK signaling downstream of TGF-β was mutually restricted in LPCs. Mechanistically, we found that TGF-β activated Smad signaling through serine phosphorylation of both the C-terminal and linker regions of Smad2 and 3 in LPCs. Additionally, TGFβ-MAPK signaling inhibited the phosphorylation of Smad3 but not Smad2 at the C-terminus, and it reinforced the linker phosphorylation of Smad3 at T179 and S213. We then found that overexpression of mutated Smad3 at linker phosphorylation sites intensifies TGF-β-induced cytostasis and EMT, mimicking the effects of MAPK inhibition in LPCs, whereas mutation of Smad3 at the C-terminus caused LPCs to blunt TGF-β-induced cytostasis and partial EMT.

CONCLUSION

These results suggested that TGF-β downstream of Smad3 and MAPK signaling were mutually antagonistic in regulating the viability and partial EMT of LPCs. This antagonism may help LPCs overcome the cytostatic effect of TGF-β under fibrotic conditions and maintain partial EMT and progenitor phenotypes.

GRIN2A mutation is a novel indicator of stratifying beneficiaries of immune checkpoint inhibitors in multiple cancers

Glutamate-NMDAR receptors (GRINs) have been reported to influence cancer immunogenicity; however, the relationship between GRIN alterations and the response to immune checkpoint inhibitors (ICIs) has not been determined. This study combined clinical characteristics and mutational profiles from multiple cohorts to form a discovery cohort (n = 901). The aim of this study was to investigate the correlation between the mutation status of the GRIN gene and the response to ICI therapy. Additionally, an independent ICI-treated cohort from the Memorial Sloan Kettering Cancer Center (MSKCC, N = 1513) was used for validation. Furthermore, this study explored the associations between GRIN2A mutations and intrinsic and extrinsic immunity using multiomics analysis. In the discovery cohort, patients with GRIN2A-MUTs had improved clinical outcomes, as indicated by a higher objective response rate (ORR: 36.8% vs 25.8%, P = 0.020), durable clinical benefit (DCB: 55.2% vs 38.7%, P = 0.005), prolonged progression-free survival (PFS: HR = 0.65; 95% CI 0.49 to 0.87; P = 0.003), and increased overall survival (OS: HR = 0.67; 95% CI 0.50 to 0.89; P = 0.006). Similar results were observed in the validation cohort, in which GRIN2A-MUT patients exhibited a significant improvement in overall survival (HR = 0.66; 95% CI = 0.49 to 0.88; P = 0.005; adjusted P = 0.045). Moreover, patients with GRIN2A-MUTs exhibited an increase in tumor mutational burden, high expression of costimulatory molecules, increased activity of antigen-processing machinery, and infiltration of various immune cells. Additionally, gene sets associated with cell cycle regulation and the interferon response were enriched in GRIN2A-mutated tumors. In conclusion, GRIN2A mutation is a novel biomarker associated with a favorable response to ICIs in multiple cancers.

Temperature-sensitive fluorescent organic nanoparticles with aggregation-induced emission for long-term cellular tracing

Temperature-sensitive organic nanoparticles with AIE effect were assembled in water from tetraphenylethene-based poly(N-isopropylacrylamide) (TPE-PNIPAM), which was synthesized by ATRP using TPE derivative as initiator. The size and fluorescence of TPE-PNIPAM nanoparticles can be tuned by varying the temperature. These nanoparticles can be internalized readily by HeLa cells and can be used as long-term tracer in live cells to be retained for as long as seven passages.

BK virus encoded microRNAs are present in blood of renal transplant recipients with BK viral nephropathy

BK viral infection is an important cause of renal transplant dysfunction and failure. Current strategies utilize surveillance for infection with DNA polymerase chain reaction assays and modulation of immunosuppression. Many viruses including polyomaviruses encode microRNAs (miRNAs). We have detected BK virus (BKV) encoded miRNAs in the blood of infected renal transplant recipients, and see a strong correlation between BKV encoded miRNA and BKV DNA in blood and a relationship between levels of bkv-miR-B1-5p and the presence of biopsy-proven BK viral nephropathy. Further research is needed to determine whether the detection of this and other virally encoded miRNAs may be useful in the diagnosis of active viral replication.

Characteristics and outcomes of discharges against medical advice among hospitalised patients

BACKGROUND

Discharge against medical advice (DAMA) occurs when an in-patient chooses to leave the hospital before discharge is recommended by the treating clinicians. The long-term outcomes of patients who DAMA are not well documented.

AIM

The objective of this long-term and hospital-wide study is to examine characteristics of patients who DAMA, their rates of readmission and mortality after self-discharge.

METHODS

Administrative data of admissions to Flinders Medical Centre between July 2002 and June 2011 were used to compare readmissions and mortality among patients who DAMA with those who did not. The outcomes were adjusted for age, gender, emergency admission status, comorbidity, mental health diagnoses, and alcohol and substance abuse.

RESULTS

In the study period, 1562 episodes (1.3%) of 121,986 admissions to Flinders Medical Centre were DAMA. Compared with those who did not leave against medical advice, these patients were younger, more often male, more likely of indigenous ethnicity and had less physical comorbidity, but greater mental health comorbidity. Half of the DAMA group stayed less than 3 days. In multivariate analysis, the relative risk for 7-day, 28-day and 1-year readmission in the DAMA group was 2.36 (95% confidence interval (CI), 1.99-2.81; P < 0.001), 1.66 (95% CI, 1.44-1.92; P < 0.001) and 1.31 (95% CI, 1.19-1.45; P < 0.001), respectively, compared with standard discharges. Furthermore, DAMA was associated with twofold (P = 0.02), 1.4-fold (P = 0.025) and 1.2-fold (P = 0.049) increase in 28-day, 1-year and up-to-9-year mortality, respectively, compared with non-DAMA.

CONCLUSIONS

Patients who self-discharged against medical advice carry a significant risk of readmission and mortality. Patients with characteristics of 'at risk of DAMA' should have greater attention paid to their care before and especially after any premature discharge.

The survival of patients with not-for-resuscitation orders

BACKGROUND

Studies have shown higher in-hospital mortality rates in patients with not-for-resuscitation (NFR) decisions. Long-term survival of these patients after their discharge from acute care is largely unknown as is communication of such decisions to primary care givers through letters or discharge summaries.

AIM

To evaluate the in-hospital mortality and post-discharge survival of general medical patients with documented resuscitation decisions as well as the prevalence of these decisions being communicated to primary health care providers through discharge summaries.

DESIGN

Retrospective cross-sectional study.

METHODS

The medical records of 618 general medical patients admitted to an Australian tertiary referral teaching hospital between January and December 2007 were reviewed to determine the documentation of resuscitation decisions. Mortality rates in-hospital and up to 5 years post-discharge were assessed in relation to the nature of any resuscitation decisions. Communication of these decisions in the discharge summaries was also evaluated.

RESULTS

One hundred and thirty-six (22%) patients had resuscitation decisions documented of whom 91 (67%) did not want resuscitation (NFR). For this NFR group, the in-hospital mortality rate was 20%, and their cumulative 1- and 5-year mortality rates were 53 and 85%, respectively. Of the 112 patients with resuscitation decisions who survived to discharge, 104 of them (93%) had discharge summaries completed but only 9 (8.4%) had resuscitation decisions documented in those discharge summaries.

CONCLUSION

Many general medical patients with a documented NFR decision survive beyond 1 year after their index admission. The rate of communication of resuscitation decisions in hospital discharge summaries is low.

The significance of reduced kidney function among hospitalized acute general medical patients

BACKGROUND

Inpatient general medical units often look after older patients who have more complex co-morbidity including renal insufficiency. The consequences of renal insufficiency with respect to length of hospital stay (LOS) and mortality have not been well described in hospitalized general medical patients.

AIM

To use a general medical inpatient population to evaluate the impact of reduced kidney function.

DESIGN

Retrospective cross-sectional study.

METHODS

We studied 504 acute medical admissions through an Acute Assessment Unit between February and November 2007. Patients were classified as having chronic kidney disease (CKD), acute kidney injury (AKI), neither (control) or both. LOS, in-hospital mortality and post-discharge survival were evaluated.

RESULTS

Renal impairment was present in 151 patients. Ninety patients had CKD only and 61 had AKI with or without CKD. In-hospital mortality was increased in those with renal impairment compared with controls (9.3 vs. 3.4%; P = 0.006). Within 4 years of admission, 187 (39%) patients had died. Post-discharge mortality was significantly higher in all renal failure populations (hazard ratio: 2.57-4.38; P < 0.01). Adjustment for patient age, gender and Charlson index explained the increased mortality during and after hospital admission but did not explain increased LOS. Only a small proportion (13%) of admitted patients with renal insufficiency had renal disease documented in their discharge summaries.

CONCLUSION

Many general medical inpatients (30%) have reduced kidney function at the time of admission. This study provides validation of the Modification of Diet in Renal Disease equation as a predictor of poor outcomes. Reduced renal function was associated with increased hospital LOS and mortality. Mortality rose with AKI and was explicable on the basis of the patients' age and co-morbidities. Renal insufficiency is documented infrequently in discharge summaries.

Resuscitation orders and their relevance to patients' clinical status and outcomes

BACKGROUND

Documented resuscitation orders have relevance in the management of a pulseless, unresponsive patient. Although useful, the frequency of their documentation in the case notes of newly admitted medical patients is not well established.

AIM

To investigate the frequency of early clear documentation of resuscitation orders in patients' admission notes.

DESIGN

Retrospective audit.

METHODS

The admission notes of 618 medical admissions to an Australian tertiary referral teaching hospital between January and December 2007 were reviewed to calculate the frequency of clear resuscitation documentation. Certain outcomes of each admission, such as in-hospital death, were obtained via hospital-based computerized records.

RESULTS

Within the first 24 h of admission, discussions regarding resuscitation were not documented for 78% of patients. Of the 482 patients with no documented resuscitation orders, 5 patients died during their index admission. Of the 136 patients with documented resuscitation orders, 24 patients died during their index admission. As age or a measure of clinical debility increased, the absolute number and relative proportion of resuscitation discussions increased significantly (P<0.0001) and the number and proportion of patients deemed not for resuscitation also increased (P<0.0001).

CONCLUSION

Those patients apparently targeted for discussion were older, more frail and acutely unwell. We propose widespread use of a clinical scoring system to identify those patients who need their resuscitation status clarified early in their admission prior to clinical deterioration.

Successful control of Scedosporium prolificans septic arthritis and probable osteomyelitis without radical surgery in a long-term renal transplant recipient

Scedosporium species are increasingly isolated from immunocompromised and immunocompetent patients. Scedosporium infections are generally resistant to multiple antifungals, and Scedosporium prolificans is particularly resistant to all single antifungal agents currently in use with in vitro testing. We report here a long-term renal transplant recipient who developed isolated S. prolificans septic monoarthritis and probable osteomyelitis. The infection was successfully treated with a combination of voriconazole and terbinafine in addition to joint washout but did not require radical surgery. This combination has been shown to have synergistic in vitro effect, and anecdotal in vivo success has also been reported recently. We also review the clinical presentation, treatment, and outcome of S. prolificans infection in patients with solid organ transplantation.

Bilateral symmetric gluteal muscle metastases from pancreatic carcinoma presenting as a myositis

Skeletal muscle metastases from pancreatic carcinoma are exceedingly rare with only a few cases reported in the published work. The case of a 59-year-old man with bilateral, symmetric gluteal muscle metastases from pancreatic carcinoma is presented. This case was clinically challenging as until skeletal muscle biopsy was carried out, the working diagnosis was that of paraneoplastic polymyositis. A brief review of the published work is also presented.