We use correlated confocal and wide-field fluorescence microscopy to probe the interplay between local variations in charge carrier recombination and charge carrier transport in methylammonium lead ...triiodide perovskite thin films. We find that local photoluminescence variations present in confocal imaging are also observed in wide-field imaging, while intensity-dependent confocal measurements show that the heterogeneity in nonradiative losses observed at low excitation powers becomes less pronounced at higher excitation powers. Both confocal and wide-field images show that carriers undergo anisotropic diffusion due to differences in intergrain connectivity. These data are all qualitatively consistent with trap-dominated variations in local photoluminescence intensity and with grain boundaries that exhibit varying degrees of opacity to carrier transport. We use a two-dimensional kinetic model to simulate and compare confocal time-resolved photoluminescence decay traces with experimental data. The simulations further support the assignment of local variations in nonradiative recombination as the primary cause of photoluminescence heterogeneity in the films studied herein. These results point to surface passivation and intergrain connectivity as areas that could yield improvements in perovskite solar cells and optoelectronic device performance.
cGAMP the travelling messenger Blest, Henry T W; Chauveau, Lise
Frontiers in immunology,
05/2023, Letnik:
14
Journal Article
Recenzirano
Odprti dostop
2'3'-cGAMP is a key molecule in the cGAS-STING pathway. This cyclic dinucleotide is produced by the cytosolic DNA sensor cGAS in response to the presence of aberrant dsDNA in the cytoplasm which is ...associated with microbial invasion or cellular damage. 2'3'-cGAMP acts as a second messenger and activates STING, the central hub of DNA sensing, to induce type-I interferons and pro-inflammatory cytokines necessary for responses against infection, cancer or cellular stress. Classically, detection of pathogens or danger by pattern recognition receptors (PRR) was thought to signal and induce the production of interferon and pro-inflammatory cytokines in the cell where sensing occurred. These interferon and cytokines then signal in both an autocrine and paracrine manner to induce responses in neighboring cells. Deviating from this dogma, recent studies have identified multiple mechanisms by which 2'3'-cGAMP can travel to neighboring cells where it activates STING independent of DNA sensing by cGAS. This observation is of great importance, as the cGAS-STING pathway is involved in immune responses against microbial invaders and cancer while its dysregulation drives the pathology of a wide range of inflammatory diseases to which antagonists have been elusive. In this review, we describe the fast-paced discoveries of the mechanisms by which 2'3'-cGAMP can be transported. We further highlight the diseases where they are important and detail how this change in perspective can be applied to vaccine design, cancer immunotherapies and treatment of cGAS-STING associated disease.
•Treatment outcomes of 3328 NPC patient treated with IMRT in Hong Kong.•8 year local/regional control remained promising.•Confirmed benefits of concurrent chemotherapy with IMRT.•Additional ...chemotherapy onto backbone of concurrent chemo-irradiation warrants further investigation.•Various severe symptomatic complications after IMRT remained low.
To evaluate treatment outcomes, failure patterns and late toxicities in patients with nasopharyngeal carcinoma (NPC) treated by intensity modulated radiotherapy (IMRT) in 6 public hospitals in Hong Kong over a 10-year period from 2001 to 2010.
Eligible patients were identified through the Hong Kong Cancer Registry data base. Clinical information was retrieved and verified by oncologists working in the individual centers. Treatment details, survival outcomes and late toxicities were analyzed.
A total of 3328 patients were recruited. The median follow-up time was 80.2 months. The 8-year actuarial overall survival (OS), local failure-free survival (LFFS), regional failure-free survival (RFFS), distant failure free survival (DFFS), progression-free survival (PFS) for the whole group was 68.5%, 85.8%, 91.5%, 81.5% and 62.6% respectively. Male gender, older age, advanced T and N stage were adverse prognostic factors for OS, DFFS and PFS, whereas use of chemotherapy in form of concurrent chemo-irradiation (CRT), neoadjuvant + CRT, or CRT + adjuvant chemotherapy were favorable prognostic factors for OS and PFS. The local control was adversely affected by advanced T stage. N stage remained as the single adverse prognostic factor for regional control. Distant metastasis was the commonest site of failure.
IMRT is an effective treatment for NPC with excellent overall loco-regional control. Distant metastasis is the major site of failure. Concurrent chemotherapy with cisplatin has an established role in NPC patients treated by IMRT.
With the ability to detect volumetric changes of contracting muscles, ultrasound (US) was a potential technique in the field of human-machine interface. Compared to the US imaging (B-mode US), the ...signal from a static single-element US transducer, A-mode US, was a more cost-effective and convenient way toward the real-world application, particularly the wearables. This study compared the performance of the single-channel A-mode US with single-channel surface electromyogram (sEMG) signals, one of the most popular signal modalities for wrist and finger gesture recognition. We demonstrated that A-mode US outperformed sEMG in six out of nine gestures recognition, while sEMG was superior to A-mode US on the detection of the rest state. We also demonstrated that, through feature space analysis, the advantage of A-mode US over sEMG for gesture recognition was due to its superior ability in detecting information from deep musculature. This study presented the clear complementary advantages between A-mode US and sEMG, indicating the possibility of fusing two signal modalities for the gesture recognition applications.
Neoadjuvant chemotherapy is becoming the standard of care for patients with locally advanced breast cancer. Conventional imaging modalities used for the assessment of tumor response to neoadjuvant ...chemotherapy rely on changes in size or morphologic characteristics and, therefore, are inherently limited.
Functional imaging technologies evaluate vascular, metabolic, biochemical, and molecular changes in cancer cells and have a unique ability to detect specific biologic tumor markers, assess therapeutic targets, predict early response to neoadjuvant chemotherapy, and guide individualized cancer therapy.
Abstract Objectives Selected patients with unresectable colorectal liver metastases (CLM) may be rendered resectable using the two‐stage hepatectomy (TSH) approach. This review was conducted with the ...aim of collating and evaluating published evidence for TSH in patients with initially unresectable CLM. Methods Searches of the MEDLINE and EMBASE databases were undertaken to identify studies of TSH in patients with initially unresectable CLM. Studies were required to focus on the perioperative treatment regimen, operative strategy, morbidity, technical success and survival outcomes. Results Ten observational studies were reviewed. A total of 459 patients with initially unresectable CLM were selected for the first stage of TSH. Preoperative chemotherapy was used in 88% of patients and achieved partial and stable response rates of 59% and 39%, respectively. Postoperative morbidity and mortality after the first stage of TSH were 17% and 0.5%, respectively. Portal vein embolization (PVE) was used in 76% of patients. Ultimately, 352 of the initial 459 (77%) patients underwent the second stage of TSH. Major liver resection was undertaken in 84% of patients; the negative margin (R0) resection rate was 75%. Postoperative morbidity and mortality after the second stage of TSH were 40% and 3%, respectively. Median overall survival was 37 months (range: 24–44 months) in patients who completed both stages of TSH. In patients who did not complete both stages of TSH, median survival was 16 months (range: 10–29 months). The 3‐year disease‐free survival rate was 20% (range: 6–27%). Conclusions Two‐stage hepatectomy is safe and effective in selected patients with initially unresectable CLM. Further studies are required to better define patient selection criteria for TSH and the exact roles of PVE and preoperative and interval chemotherapy.
The borylamino-diborata-allyl anion Shere, Henry T. W; Liu, Han-Ying; Neale, Samuel E ...
Chemical science,
05/2024, Letnik:
15, Številka:
21
Journal Article
Recenzirano
Odprti dostop
Reactions of β-diketiminato alkaline earth alkyldiboranate derivatives (BDI)Ae{pinBB(R)pin} (BDI = HC{(Me)CNDipp}
2
; Dipp = 2,6-i-Pr
2
C
6
H
3
; Ae = Mg, R =
n
-Bu or Ae = Ca, R =
n
-hexyl) with
t
...-BuNC provide access to the respective group 2 derivatives of unprecedented diborata-allyl, {(pinB)
2
CNBpin(
t
-Bu)}
−
, anions. Although the necessary mode of B-C bond cleavage implicated in these transformations could not be elucidated, further studies of the reactivity of magnesium triboranates toward isonitriles delivered a more general and rational synthetic access to analogous anionic moieties. Extending this latter reactivity to a less symmetric triboranate variant also provided an isomeric Mg-C-bonded dibora-alkyl species and sufficient experimental insight to prompt theoretical evaluation of this reactivity. DFT calculations, thus, support a reaction pathway predicated on initial RNC attack at a peripheral boron centre and the intermediacy of such dibora-alkyl intermediates.
Reactions of alkaline earth alkyldiboranate and triboranate derivatives with organic isonitriles provides access to unprecedented diborata-allyl anions.
Aim
To review the current status of the novel technique of endoscopic necrosectomy in the management of pancreatic necrosis after acute pancreatitis.
Methods
Studies were identified by searching ...Medline, PubMed and Embase databases for articles from January 1990 to December 2009 using the keywords “acute pancreatitis”, “pancreatic necrosis” and “endoscopy”. Additional papers were identified by a manual search of the references from the key articles. Case series of fewer than five patients and case reports were excluded.
Results
Indications, techniques and outcomes of endoscopic necrosectomy were analysed. There were no randomised controlled trials identified. Ten case series were included in this analysis. There were a total of more than 1,100 endoscopic necrosectomy procedures in 260 patients with pancreatic necrosis. One hundred fifty-five were proven to be infected necrosis on culture. The overall mortality rate was 5%. The mean procedure-related morbidity rate was 27%. The rate of complete resolution of pancreatic necrosis with the endoscopic method alone was 76%.
Conclusions
Endoscopic necrosectomy is a safe and effective treatment option in selected patients with pancreatic necrosis after acute pancreatitis. Future studies will be required to further define the selection criteria and the techniques for the endoscopic procedure.
PDF
