ABSTRACT
This study investigates methylation patterns in circulating cell-free DNA (ccfDNA) for their potential role in colorectal cancer (CRC) detection and the monitoring of treatment response. Through methylation microarrays and quantitative PCR assays, we analyzed 440 samples from The Cancer Genome Atlas (TCGA) and an additional 949 CRC samples. We detected partial or extensive methylation in over 85% of cases within three biomarkers: EFEMP1, SFRP2, and UNC5C. A methylation score for at least one of the six candidate regions within these genes' promoters was present in over 95% of CRC cases, suggesting a viable detection method. In evaluating ccfDNA from 97 CRC patients and 62 control subjects, a difference in methylation and recovery signatures was observed. The combined score, integrating both methylation and recovery metrics, showed high diagnostic accuracy, evidenced by an area under the ROC curve of 0.90 (95% CI = 0.86 to 0.94). While correlating with tumor burden, this score gave early insight into disease progression in a small patient cohort. Our results suggest that DNA methylation in ccfDNA could serve as a sensitive biomarker for CRC, offering a less invasive and potentially more cost-effective approach to augment existing cancer detection and monitoring modalities, possibly supporting comprehensive genetic mutation profiling.
Subject(s)
Cell-Free Nucleic Acids , Colorectal Neoplasms , Humans , DNA Methylation , Biomarkers, Tumor/genetics , Biomarkers, Tumor/metabolism , Colorectal Neoplasms/diagnosis , Colorectal Neoplasms/genetics , Colorectal Neoplasms/pathology , Cell-Free Nucleic Acids/genetics , Treatment Outcome , Mutation , Extracellular Matrix Proteins/geneticsABSTRACT
A significant association exists between the gut microbiome and colorectal carcinogenesis, as well as cancer progression. It has been reported that Escherichia coli (E. coli) containing polyketide synthetase (pks) island contribute to colorectal carcinogenesis by producing colibactin, a polyketide-peptide genotoxin. However, the functions of pks+ E. coli in initiation, proliferation, and metastasis of colorectal cancer (CRC) remain unclear. We investigated the clinical significance of pks+ E. coli to clarify its functions in CRC. This study included 413 patients with CRC. Pks+ E. coli of tumor tissue and normal mucosal tissue were quantified using droplet digital PCR. Pks+ E. coli was more abundant in Stages 0-I tumor tissue than in normal mucosal tissue or in Stages II-IV tumor tissue. High abundance of pks+ E. coli in tumor tissue was significantly associated with shallower tumor depth (hazard ratio [HR] = 5.0, 95% confidence interval [CI] = 2.3-11.3, p < 0.001) and absence of lymph node metastasis (HR = 3.0, 95% CI = 1.8-5.1, p < 0.001) in multivariable logistic analyses. Pks+ E. coli-low and -negative groups were significantly associated with shorter CRC-specific survival (HR = 6.4, 95% CI = 1.7-25.6, p = 0.005) and shorter relapse-free survival (HR = 3.1, 95% CI = 1.3-7.3, p = 0.01) compared to the pks+ E. coli-high group. Pks+ E. coli was abundant in Stages 0-I CRC and associated with CRC prognosis. These results suggest that pks+ E. coli might contribute to carcinogenesis of CRC but might not be associated with tumor progression.
Subject(s)
Colorectal Neoplasms , Polyketides , Humans , Escherichia coli/genetics , Neoplasm Recurrence, Local , Mucous Membrane , CarcinogenesisABSTRACT
The development of therapies that target cancer stem cells (CSCs) is an important challenge in cancer research. The antioxidant system is enhanced in CSCs, which may lead to resistance to existing therapies. Ascorbic acid (AA) has the potential to act as both an antioxidant and a pro-oxidant agent, but its effects on CSCs are a subject of current research. Here, we investigated the effect of AA focusing specifically on CSCs with the hepatocellular carcinoma cell line Li-7. The Li-7 cell line is heterogenous consisting of CD166- and CD166+ cells; CD166- cells include CSC-like cells (CD13+CD166- cells) and CD13-CD166- cells that can revert to CD13+CD166- cells. The addition of AA to the culture medium caused cell death in both cell populations in CD166- cells in a concentration dependent manner. In contrast, AA administration had a limited effect on CD166+ non-CSC cells. The level of reactive oxygen species after AA treatment was elevated only in CD166- cells. The effect of AA only occurred at low cell densities in 2D and 3D cultures. In a mouse tumor model injected with Li-7 cells, intraperitoneal administration of AA failed to prevent tumor formation but appeared to delay tumor growth. Our findings shed light on why AA administration has not become a mainstream treatment for cancer treatment; however, they also show the possibility that AA can be used in therapies to suppress CSCs.
Subject(s)
Carcinoma, Hepatocellular , Liver Neoplasms , Animals , Mice , Carcinoma, Hepatocellular/pathology , Liver Neoplasms/pathology , Cell Line, Tumor , Ascorbic Acid/pharmacology , Ascorbic Acid/metabolism , Antioxidants/pharmacology , Antioxidants/metabolism , Neoplastic Stem Cells/pathologyABSTRACT
CD4+ T cells play a key role in the immune response via their differentiation into various helper T cell subsets that produce characteristic cytokines. Epigenetic changes in CD4+ T cells are responsible for cytokine production in these subsets, although the exact molecular mechanisms remain unclear. Therefore, we investigated the effects of plant homeodomain finger protein 2 (PHF2), a histone H3K9 demethylase, on cytokine production in CD4+ T cells using T cell-specific Phf2-conditional knockout (cKO) mice in this study. we showed that interleukin 4 (Il4) expression was significantly decreased in Phf2-cKO CD4+ T cells compared to that in wild-type cells. To further elucidate the role of PHF2 in vivo, we assessed immune responses in a mouse model of ovalbumin (OVA)-induced atopic dermatitis. Phf2-cKO mice exhibited lower serum levels of OVA-specific IgE than those in wild-type mice. These findings suggest that PHF2 plays a role in promoting T helper 2 cell (Th2) function and may contribute to the pathogenesis of Th2-related allergies such as atopic dermatitis. This study demonstrated the impact of PHF2 on cytokine production in CD4+ T cells for the first time. Further studies on the PHF2-mediated epigenetic mechanisms may lead to the development of treatments for a variety of immune diseases.
Subject(s)
Dermatitis, Atopic , Homeodomain Proteins , Animals , Mice , Cytokines , Homeodomain Proteins/genetics , Homeodomain Proteins/metabolism , Interleukin-4 , Ovalbumin , Th2 Cells/metabolismABSTRACT
We here report a new molecule DoNA binding to a CAG repeat RNA. DoNA is a dimer of the NA molecule that we previously reported. NA binds with high affinity to a CAG repeat DNA but not significantly to a CAG repeat RNA. Binding analyses using SPR and CSI-TOF MS indicated a significant increase in the affinity of DoNA to a single stranded CAG repeat RNA compared to NA. Systematic investigation of the RNA motifs bound by DoNA using hairpin RNA models revealed that DoNA binds to the CAG units at overhang and terminal positions, and notably, it binds to the structurally flexible internal and hairpin loop region.
Subject(s)
RNA , Trinucleotide Repeats , RNA/chemistry , DNA/chemistry , Nucleotide MotifsABSTRACT
BACKGROUND: Comprehensive genomic profiling (CGP) can aid the discovery of clinically useful, candidate antitumor agents; however, the variant annotations sometimes differ among the various types of CGP tests as well as the public database. The aim of this study is to clarify the genomic landscape of evaluating detected variants in patients with a malignant solid tumor. METHODS: The present, cross-sectional study used data from 57,084 patients with a malignant solid tumor who underwent CGP at the Center for Cancer Genomics and Advanced Therapeutics (C-CAT) between June 1, 2019 and August 18, 2023. The pathogenicity of the variants was annotated using public databases. RESULTS: As a result of re-annotation of the detected variants, 20.1% were pathogenic and 1.4% were benign. The mean number of pathogenic variants was 4.30 (95% confidence interval: 4.27-4.32) per patient. Of the entire cohort, 5.7% had no pathogenic variant. The co-occurrence of the genes depended on the tumor type. Germline findings were detected in 6.2%, 8.8%, and 15.8% of the patients using a tumor/normal panel, tumor-only panel, and liquid panel, respectively, with the most common gene being BRCA2 followed by TP53 and BRCA1. CONCLUSIONS: The detected variants should be re-annotated because several benign variants or variants of unknown significance were included in the CGP, and the genomic landscape derived from these results will help researchers and physicians interpret the results of CGP tests. The method of extracting presumptive, germline, pathogenic variants from patients using a tumor-only panel or circulating tumor DNA panel requires improvement.
ABSTRACT
BACKGROUND: We previously showed that daily nutritional intervention with an oral elemental diet (ED) at 300 kcal/day for 6-8 weeks postoperatively decreased the percentage of body weight loss (%BWL), and that the effect was maintained for 1 year. This post hoc analysis aimed to determine whether this intervention decreased skeletal muscle mass loss 1-year post-gastrectomy. METHODS: Data from consecutive, untreated patients with histopathologically confirmed stage I-III gastric adenocarcinoma who planned to undergo total gastrectomy (TG) or distal gastrectomy (DG) and were enrolled in a previously published randomized trial were used. The primary endpoint was the percentage of skeletal muscle mass index (%SMI) loss from baseline at 1 year postoperatively, based on abdominal computed tomography images obtained preoperatively and at 1 year postoperatively. RESULTS: The overall median %SMI loss was lower in the ED versus control group, but the difference was not significant. The difference in %SMI loss in the ED and control groups was greater in patients with TG (10.1 vs. 13.0; P = 0.12) than in those with DG (5.5 vs. 6.8; P = 0.69). A correlation was observed between %BWL and %SMI loss in both groups (ED group, coefficient 0.591; control group, coefficient 0.644; P < 0.001 for both). Type of gastrectomy (coefficient 7.38; P = 0.001) and disease stage (coefficient - 6.43; P = 0.04) were independent predictors of postoperative skeletal muscle mass loss. CONCLUSION: ED administration for 6-8 weeks following gastrectomy had no inhibitory effect on skeletal muscle loss at 1 year postoperatively. CLINICAL TRIAL REGISTRATION: UMIN000023455.
Subject(s)
Adenocarcinoma , Stomach Neoplasms , Humans , Stomach Neoplasms/surgery , Stomach Neoplasms/pathology , Muscle, Skeletal/pathology , Postoperative Period , Adenocarcinoma/pathology , Gastrectomy/adverse effects , Postoperative Complications/etiologyABSTRACT
PURPOSE: Emergency surgery (ES) for complicated appendicitis (CA) is associated with high morbidity. Interval appendectomy (IA) decreases this rate; however, nonoperative management (NOM) is not always successful. Some patients require unplanned ES due to NOM failure (IA failure: IA-F). This study aimed to verify the benefits of IA and to evaluate the risk factors for NOM failure. METHODS: Patients diagnosed with CA who underwent surgery between January 2012 and December 2021 were included in this study. We compared the surgical outcomes of the ES group with those of the IA success (IA-S) and IA-F groups. We also analyzed 14 factors that predicted NOM failure. RESULTS: Among 302 patients, the rate of severe complications (Clavien-Dindo grade ≥ III) was significantly higher in the ES group (N = 165) than in the IA-S group (N = 102). The rates were equal between the ES (N = 165) and IA-F (N = 35) groups. NOM was successful in 110 patients and failed in 27. Lack of abscesses, comorbidities, high WBC count, and free air were independent risk factors for NOM failure. CONCLUSIONS: Considering the benefits of IA and the non-inferior surgical outcomes of IA-F compared to ES, IA is a good therapeutic strategy for CA. However, in patients exhibiting four independent risk factors for NOM failure, careful monitoring of unplanned ES is necessary.
ABSTRACT
PURPOSE: Self-expandable metallic stent (SEMS) placement is widely used as a bridge to surgery (BTS) procedure for obstructive colorectal cancer. However, evidence regarding the optimal interval between SEMS placement and elective surgery is lacking. METHODS: We retrospectively collected data from patients with BTS between January 2013 and October 2021. Inverse probability treatment-weighted propensity score analyses were used to compare short- and long-term outcomes between the short-interval (SI) and long-interval (LI) groups, using a cutoff of 20 days. RESULTS: In total, 138 patients were enrolled in this study (SI group, n = 63; LI group, n = 75). In the matched cohort, the patients' backgrounds were well balanced. The incidence of Clavien-Dindo grade ≥ II postoperative complications was not significantly different between the SI and LI groups (19.0% vs. 14.0%, P = 0.47). There were no significant differences between the SI and LI groups in the 3-year recurrence-free survival (68.0% vs. 76.4%, P = 0.73) or 3-year overall survival rates (86.0% vs. 90.6%, P = 0.72). CONCLUSIONS: A longer interval did not deteriorate the oncological outcomes. Individual perioperative management with an appropriate interval to improve the patient's condition is required to ensure safe surgery.
ABSTRACT
BACKGROUND: The precise diagnosis and medical management of patients with suspected familial adenomatous polyposis should be based on genetic testing, which may not always be available. Therefore, establishing a new model for predicting the likelihood of a germline pathogenic variant (GPV) of APC based on its clinical manifestations could prove to be useful in clinical practice. METHODS: The presence of GPVs of APC gene was investigated in 162 patients with adenomatous polyposis (≥ 10 polyps) using a multigene panel or single-gene testing. To generate a predictive model for GPV of the APC gene, a logistic regression analysis was performed using the clinicopathological variables available at the time of the diagnosis of adenomatous polyposis. RESULTS: Ninety (55.6%) patients had GPV of the APC gene. According to a multivariate logistic regression analysis, age < 40 years, polyps ≥ 100, fundic gland polyposis, and a family history of colorectal polyposis were found to be independent predictors of the GPV of APC and were used to establish a formula for predicting the GPV of APC using the four predictors. The prediction model had an area under the curve of 0.91 (0.86-0.96) according to a receiver operating characteristic analysis. CONCLUSION: The model for predicting the GPV of APC will help patients with adenomatous polyposis and physicians make decisions about genetic testing.
ABSTRACT
OBJECTIVES: The JAVELIN Bladder 100 phase 3 trial showed that avelumab first-line maintenance + best supportive care significantly prolonged overall survival and progression-free survival versus best supportive care alone in patients with advanced urothelial carcinoma who were progression-free following first-line platinum-based chemotherapy. We report findings from J-AVENUE (NCT05431777), a real-world study of avelumab first-line maintenance therapy in Japan. METHODS: Medical charts of patients with advanced urothelial carcinoma without disease progression following first-line platinum-based chemotherapy, who received avelumab maintenance between February and November 2021, were reviewed. Patients were followed until June 2022. The primary endpoint was patient characteristics; secondary endpoints included time to treatment failure and progression-free survival. RESULTS: In 79 patients analyzed, median age was 72 years (range, 44-86). Primary tumor site was upper tract in 45.6% and bladder in 54.4%. The most common first-line chemotherapy regimen was cisplatin + gemcitabine (63.3%). Median number of chemotherapy cycles received was four. Best response to chemotherapy was complete response in 10.1%, partial response in 58.2%, and stable disease in 31.6%. Median treatment-free interval before avelumab was 4.9 weeks. With avelumab first-line maintenance therapy, the disease control rate was 58.2%, median time to treatment failure was 4.6 months (95% CI, 3.3-6.4), and median progression-free survival was 6.1 months (95% CI, 3.6-9.7). CONCLUSIONS: Findings from J-AVENUE show the effectiveness of avelumab first-line maintenance in patients with advanced urothelial carcinoma in Japan in clinical practice, with similar progression-free survival to JAVELIN Bladder 100 and previous real-world studies, supporting its use as a standard of care.
Subject(s)
Antibodies, Monoclonal, Humanized , Carcinoma, Transitional Cell , Maintenance Chemotherapy , Adult , Aged , Aged, 80 and over , Female , Humans , Male , Middle Aged , Antibodies, Monoclonal, Humanized/therapeutic use , Antibodies, Monoclonal, Humanized/administration & dosage , Antineoplastic Agents, Immunological/therapeutic use , Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Carcinoma, Transitional Cell/drug therapy , Carcinoma, Transitional Cell/mortality , Carcinoma, Transitional Cell/pathology , Japan , Maintenance Chemotherapy/methods , Progression-Free Survival , Retrospective Studies , Treatment Outcome , Urinary Bladder Neoplasms/drug therapy , Urinary Bladder Neoplasms/pathology , Urinary Bladder Neoplasms/mortality , Urologic Neoplasms/drug therapy , Urologic Neoplasms/mortality , Urologic Neoplasms/pathologySubject(s)
Colorectal Neoplasms , Humans , Colorectal Neoplasms/surgery , Retrospective Studies , Preoperative CareABSTRACT
Circular RNAs (circRNAs), are a covalently closed, single-stranded RNA without 5'- and 3'-termini, commonly stem from the exons of precursor mRNAs (pre-mRNAs). They have recently garnered interest, with studies uncovering their pivotal roles in regulating various aspects of cell functions and disease progressions. A notable feature of circRNA lies in the mechanism of its biogenesis involving a specialized form of splicing: back-splicing. A splicing process that relies on interactions between introns flanking the circularizing exon to bring the up and downstream splice sites in proximity through the formation of a prerequisite hairpin structure, allowing the spliceosomes to join the two splice sites together to produce a circular RNA molecule. Based on this mechanism, we explored the feasibility of facilitating the formation of such a prerequisite hairpin structure by utilizing a newly designed oligonucleotide, CircuLarIzation Promoting OligoNucleotide (CLIP-ON), to promote the production of circRNA in cells. CLIP-ON was designed to hybridize with and physically bridge two distal sequences in the flanking introns of the circularizing exons. The feasibility of CLIP-ON was confirmed in HeLa cells using a model pre-mRNA, demonstrating the applicability of CLIP-ON as a trans-acting modulator to upregulate the production of circRNAs in a cellular environment.
Subject(s)
RNA, Circular , RNA , Humans , RNA, Circular/genetics , HeLa Cells , RNA/genetics , RNA/metabolism , RNA Splicing/genetics , RNA Precursors/metabolismABSTRACT
The structure of the complex formed by naphthyridine carbamate dimer (NCD) binding to CGG repeat sequences in DNA, associated with fragile X syndrome, has been elucidated using 15N-labeled NCD and 1H-15N HSQC. In a fully saturated state, two NCD molecules consistently bind to each CGG/CGG unit, maintaining a 1 : 2 binding stoichiometry.
Subject(s)
Carbamates , Noncommunicable Diseases , Humans , Naphthyridines/chemistry , DNA/chemistry , Magnetic Resonance Spectroscopy , Trinucleotide RepeatsABSTRACT
Coronavirus disease 2019 (COVID-19) is associated with an increased risk of thromboembolic events. However, there are few reports on multiple thromboembolic events in young patients with COVID-19. Herein, we report a case of multiple visceral arterial embolisms secondary to acute myocardial infarction in a young patient with COVID-19. A 36-year-old male developed sudden chest pain after being diagnosed with COVID-19. Emergency coronary angiography revealed total occlusion of the right coronary artery, and the patient underwent a subsequent emergency percutaneous coronary intervention (PCI) which achieved successful recanalization. The patient was administered a loading dose and a subsequent maintenance dose of aspirin and prasugrel and a continuous intravenous infusion of unfractionated heparin at 10,000â¯units per day. Echocardiography detected a left ventricular apical thrombus 3â¯days after PCI; a loading dose of warfarin was administered and promptly reached the therapeutic range. However, the patient developed superior mesenteric artery embolism and renal infarction on the 12th day after PCI. COVID-19 was considered to play a role in the thromboembolic events observed in this patient. This case highlights the need for individualized antithrombotic regimens when managing patients with COVID-19 who develop acute myocardial infarction. Learning objective: Reportedly, coronavirus disease 2019 (COVID-19) is associated with an increased risk of venous and arterial thromboembolic events. However, few reports have described multiple thromboembolic events in younger patients with COVID-19. This case report describes arterial thromboembolism secondary to acute myocardial infection (AMI) in a patient with COVID-19. It highlights the need for individualized antithrombotic regimens when managing patients with COVID-19 who develop AMI.
ABSTRACT
For the development of the next generation of fuel cells, it is essential to create an innovative design principle of polymer electrolytes that is beyond extension of the existing strategy. In the present study, we focused on the surface hopping proton conduction mechanism where an activation energy for proton conduction is greatly reduced by decreasing the distance between SO3- groups. Our gyroid nanostructured polymer film (Film-G), with a hydrophilic surface where the SO3- groups are aligned densely and precisely, shows high proton conductivity of the order of 10-2 S cm-1 when the water content is about 15 wt%. We reveal that the high proton conductivity of Film-G is attributed to the exhibition of an extremely-fast surface hopping conduction mechanism due to the reduced activation energy barrier along the gyroid minimal surface. This finding should introduce a game-changing novel opportunity in polymer electrolyte design.
ABSTRACT
Oxaliplatin, a platinum-based chemotherapeutic agent, frequently causes acute and chronic peripheral sensory neuropathy, for which no effective treatment has been established. In particular, chronic neuropathy can persist for years even after treatment completion, thus worsening patients' quality of life. To avoid the development of intractable adverse effects, a predictive biomarker early in treatment is awaited. In this study, we explored extracellular long non-coding RNAs (lncRNAs) released from primary sensory neurons as biomarker candidates for oxaliplatin-induced peripheral neuropathy. Because many human-specific lncRNA genes exist, we induced peripheral sensory neurons from human induced pluripotent stem cells. Oxaliplatin treatment changed the levels of many lncRNAs in extracellular vesicles (EVs) released from cultured primary sensory neurons. Among them, the levels of release of lncRNAs that were considered to be selectively expressed in dorsal root ganglia were correlated with those of lncRNAs in plasma EV obtained from healthy individuals. Several lncRNAs in plasma EVs early after the initiation of treatment showed greater changes in patients who did not develop chronic neuropathy that persisted for more than 1 year than in those who did. Therefore, these extracellular lncRNAs in plasma EVs may represent predictive biomarkers for the development of chronic peripheral neuropathy induced by oxaliplatin.
Subject(s)
Biomarkers , Induced Pluripotent Stem Cells , Oxaliplatin , Peripheral Nervous System Diseases , RNA, Long Noncoding , Sensory Receptor Cells , Oxaliplatin/adverse effects , Humans , RNA, Long Noncoding/genetics , RNA, Long Noncoding/blood , Induced Pluripotent Stem Cells/metabolism , Sensory Receptor Cells/drug effects , Sensory Receptor Cells/metabolism , Biomarkers/blood , Biomarkers/metabolism , Peripheral Nervous System Diseases/blood , Peripheral Nervous System Diseases/chemically induced , Peripheral Nervous System Diseases/pathology , Male , Extracellular Vesicles/metabolism , Extracellular Vesicles/drug effects , Female , Ganglia, Spinal/drug effects , Ganglia, Spinal/metabolism , Ganglia, Spinal/pathology , Chronic Disease , Middle Aged , Cells, CulturedABSTRACT
Background: Anemia has negative effects on long-term outcomes of rectal cancer patients; however, its status as a risk factor for severe complications is disputed. Perioperative risks may differ based on the severity of pre-surgical anemia; nonetheless, no previous study has investigated these differences. This study identified risks of severe postoperative complications in rectal cancer patients based on severity of their pre-surgical anemia. Materials and Methods: This study enrolled patients who underwent low anterior resection for rectal cancer and were registered in the Japanese National Clinical Database (NCD) between 2017 and 2019. Anemia severity was categorized into three levels: mild, moderate, and severe. A logistic regression model was applied to calculate the risk-adjusted odds ratio (OR) of severe complications after surgery. Results: This study analyzed a cohort of 51 765 rectal cancer patients who underwent low anterior resection. Results showed that severe complications occurred in 10.9% of patients and were significantly more frequent in patients with anemia (13.6%) than those with normal hemoglobin levels (9.2%). Risk-adjusted ORs of severe complications in the severe, moderate, and mild anemia groups versus the normal group for males were 1.19 (95% confidence interval [CI]: 0.89-1.58), 1.47 (1.34-1.62), and 1.21 (1.12-1.31), respectively. Those for females were 1.39 (0.90-2.15), 1.64 (1.37-1.97), and 1.36 (1.16-1.58), respectively. Conclusions: According to this large cohort study, pre-surgical anemia significantly increases the risk of severe postoperative complications in rectal cancer patients. Even mild anemia presents a significant risk.
ABSTRACT
The protein dynamical transition at ~200 K, where the biomolecule transforms from a harmonic, non-functional form to an anharmonic, functional state, has been thought to be slaved to the thermal activation of dynamics in its surface hydration water. Here, by selectively probing the dynamics of protein and hydration water using elastic neutron scattering and isotopic labeling, we found that the onset of anharmonicity in the two components around 200 K is decoupled. The one in protein is an intrinsic transition, whose characteristic temperature is independent of the instrumental resolution time, but varies with the biomolecular structure and the amount of hydration, while the one of water is merely a resolution effect.