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Our cohort included a total of 277 patients diagnosed with primary nasopharyngeal carcinoma in The First People’s Hospital of Foshan, China. All selected subjects were histopathologically confirmed as primary NPC without a prior history of radiation therapy, chemotherapy, or other malignancies that could potentially distort the tumor morphology. All patients were restaged according to the eighth edition of the Union for International Cancer Control/American Joint Committee on Cancer (UICC/AJCC) staging system²⁷. The collected patients with age, gender, TNM stages, histopathological diagnosis, EBV status (VCA-IgA, EBV-DNA) and the five-year progression-free survival further contributed to the clinical database. The process of data is depicted in Fig. 1.

In our study, the image acquisition process was meticulously structured to ensure the highest quality of data for investigating nasopharyngeal carcinoma (NPC) segmentation. All cases underwent both non-contrast and contrast-enhanced MRI scans, providing comprehensive imaging and clinical data (see Table 4). The exclusion criteria included: 1. patients who had undergone radiotherapy or chemotherapy before the MRI examination, as the internal tumor structure and lesion boundaries may change after treatment, preventing an accurate reflection of the tumor’s original growth state; 2. patients with a history of other malignant tumors, which may confound variables and affect the study’s outcomes; 3. images that did not meet quality standards: (1) Incomplete scan coverage: When lesion areas were excessively large, parts of the lesions may have extended beyond the imaging field, resulting in incomplete evaluation of the entire NPC lesion. (2) Insufficient image resolution: Low-resolution images hindered accurate segmentation of tumor boundaries, potentially leading to imprecise measurements and analysis. (3) Presence of artifacts: Various imaging artifacts,such as motion or susceptibility effects, could obscure or distort the appearance of lesions, reducing the reliability of assessments.

The dataset was captured using six MR scanners from manufacturers including GE Discovery MR750w 3.0T and Philips Achieva 1.5T systems with Gadoteric Acid Meglumine Salt as the contrast agent. The setup and calibration of the six MR scanners (see Table 3) were similar, as can be seen from the STD of machine parameters in Table 1.

To ensure the privacy and confidentiality of patient information, a strict anonymization protocol was applied. Personal identifiers such as names, ages, birth data, sex, weight, content date were removed. Furthermore, unique patient IDs were replaced with the patients’ index within the dataset. Indirect identifiers were also deleted to prevent any potential re-identification, e.g., study date and institute information.

Standardization and Calibration of MRI Machines

To ensure consistency across different imaging sessions, a rigorous standardization and calibration protocol was implemented for all MRI scanners following international quality assurance standards. The calibration process aimed to minimize variations due to machine-specific differences and environmental factors.

Calibration Procedure

Each MRI machine was calibrated before the commencement of the study and checked regularly throughout the imaging period. The main aspects of the calibration process included:

• Geometric calibration: Ensuring the geometric accuracy of the images by calibrating the scanner’s spatial resolution settings using a standardized phantom object.

• Signal intensity calibration: Standardizing the signal intensity levels by adjusting the MR signal parameters to match a predefined baseline, ensuring consistent image brightness and contrast across sessions.

• Magnetic field homogeneity adjustment: Regularly assessing and optimizing the magnetic field homogeneity to reduce artifacts and improve the accuracy of the image data.

Quality Assurance

To maintain the calibration standards, quality assurance tests were conducted periodically. These tests involved:

• Acquiring images of a standard test phantom that includes structures to evaluate resolution, contrast, and signal uniformity.

• Comparing these images against reference images to detect any deviations that might indicate a need for recalibration.

Segmentation procedure

Recognizing the importance of high-quality manually segmented data in advancing NPC imaging research, we have decided to share our meticulously curated dataset of manual NPC segmentations. This dataset, created by experienced radiologists using a standardized protocol, encompasses multiple MRI sequences and provides a valuable resource for researchers and developers working on improving NPC segmentation techniques.

The segmentation procedure was a critical step in preparing MRI data for effective analysis. Since the manual segmentation is widely regarded as the gold standard due to its high accuracy, all the MRI images in this study were manually segmented.

1. Image Review and Tumor Identification: All three sequence images were thoroughly reviewed to define tumor regions and areas of surrounding invasion. The process involved: (1) Localization: Confirming that the lesion originated from the nasopharyngeal mucosa or submucosa, typically presenting as early-stage mucosal thickening or soft tissue mass formation. On T1WI, lesions appeared as equal or high signals, while on T2WI, they showed high signals. CE-T1W images demonstrated significant enhancement. (2) Invasion Assessment: Larger lesions often exhibited invasion into surrounding structures. This could manifest as: a. Parapharyngeal space involvement, characterized by the disappearance of surrounding fat planes and muscle invasion. b. Upward extension with skull base bone destruction and intracranial invasion. Bone destruction was evident as high-signal yellow bone marrow was replaced by low-signal tumor tissue. c. Intracranial invasion commonly affects the cavernous sinus, temporal lobe, and cerebellopontine angle region. d. Cervical lymph node metastases, typically showing a top todown, ipsilateral to contralateral sequential pattern.

2. Tumor Boundary Determination: Nasopharyngeal MRI scans usually include T1, T2, and CE-T1 sequences in axial, coronal, and sagittal planes. Radiologists integrated information from all three sequences to accurately determine tumor boundaries: T1WI effectively displayed the surrounding fat spaces and muscle structures. CE-T1WI was crucial for precise boundary determination of early mucosal thickening. T2WI helped differentiate tumor mass from mucosa, with the mass typically showing lower signal intensity than the mucosa.

3. Manual Segmentation Procedure: Two experienced diagnostic radiologists, each with over ten years of work experience, independently performed layer-by-layer manual segmentation of lesion boundaries using ITK-SNAP 3.6.1 software (version 3.6.1)²⁸. The polygon mode drawing icon was utilized for all three sequences in the axial plane.

4. Specific Steps for Manual Segmentation: (1) Data Import: – DICOM format neck MR images exported from the Picture Archiving and Communication System (PACS), including the nasopharyngeal region, were imported into ITK-SNAP software. (2) Data Retrieval and Visualization: Window width and level were adjusted for optimal lesion edge visualization. Relevant slices containing lesions were selected for ROI annotation. (3) ROI Delineation and Adjustment: ROIs were manually delineated layer-by-layer, following the inner lesion boundary to reduce partial volume effects. For extensive tumors, care was taken to exclude adjacent structures (e.g., blood vessels, lymph nodes) while including direct invasion areas. Difficult boundaries in one sequence were cross-referenced with other sequences. Both continuous and point-by-point delineation methods were used, with manual adjustments as needed to ensure accuracy. After completing all layers, 3D segmentation images were generated for each sequence per patient.

The segmented tumor regions were then converted into binary masks, representing the presence or absence of tumor tissue in each pixel. This rigorous segmentation procedure ensured the creation of a highly accurate and reliable dataset, forming a robust foundation for our subsequent analyses on NPC segmentation.

Mass General Brigham researchers identified seven molecules in the blood linked to excessive daytime sleepiness, including factors related to diet and hormones.

Approximately one in three Americans reports experiencing overwhelming drowsiness during the day-a condition known as excessive daytime sleepiness (EDS). EDS is linked to an increased risk of serious conditions such as cardiovascular disease, obesity, and diabetes. A new study led by investigators from Mass General Brigham and Beth Israel Deaconess Medical Center identifies several molecules in the blood, known as metabolites, that are linked to EDS. Findings suggest that risk of the condition may be influenced by both internal body processes, such as hormone levels, and external factors such as diet. Results are published in Lancet eBioMedicine. 

Our study suggests diet and genetics may play an important role in EDS. As we learn what’s happening biologically, we are beginning to understand how and why EDS occurs, the early signs that someone might have it, and what we can do to help patients.” 

Tariq Faquih, PhD, lead author, postdoctoral fellow in the Division of Sleep and Circadian Disorders at Brigham and Women’s Hospital

Researchers collected data on 877 metabolites, naturally occurring molecules in the body influenced by diet and hormones. The team used blood samples from 6,000 participants in the Hispanic Community Health Study/Study of Latinos. The team also used data from a questionnaire that assesses how often a person dozes off during the day in various scenarios. The team replicated the findings in The Multi-Ethnic Study of Atherosclerosis (MESA) study and studies in the UK and Finland. 

They identified seven metabolites associated with EDS. An additional three metabolites were identified that varied by sex. The team found that omega-3 and omega-6 fatty acids, which are commonly found in foods that make up Mediterranean-like diets, were associated with lower risk of EDS. Other metabolites, such as tyramine, which is found in fermented and overripe foods, were associated with increased daytime sleepiness, particularly in men. Sex steroid metabolites, such as progesterone, were associated with sleep-related processes such as melatonin production. 

Researchers note that the results suggest potential treatment targets for EDS and that dietary changes or medications may lead to better treatment. They also note some limitations to the study, including difficulty in interpreting exact values of metabolites and using a sleep questionnaire instead of bringing participants into a sleep lab for tests. 

Future directions could include conducting a clinical trial to see if dietary changes or supplements can help reduce daytime sleepiness. Additionally, the authors identified some unknown metabolites that they plan to explore further. 

“Conducting a clinical trial would be a big next step and could help us understand if omega-3s and omega-6s obtained from diet could help lower risk of EDS,” said Faquih. 

Published on
20/08/2025 – 7:00 GMT+2

Young teenagers who have sleep problems are at higher risk of engaging in self-harm by the time they turn 17, a new study has found.

UK researchers found that self-reported sleep problems at age 14 were directly associated with self-harming behaviour both then and at age 17.

The results indicate that sleep patterns can have long-lasting impacts on teenagers’ wellbeing, the researchers said.

“Self-harm is one of the leading causes of death among adolescents and young adults,” said Nicole Tang, one of the study’s authors and a clinical and health psychologist at the University of Warwick.

“Knowing that poor and fragmented sleep is often a marker preceding or co-occurring with suicidal thoughts and behaviour, it gives us a useful focus for risk monitoring and early prevention,” she added.

In recent years, sleep deficiency and self-harm in young people have separately emerged as public health concerns in Europe.

The share of teenagers who meet sleep recommendations on school days range from 32 per cent in Poland to 86.3 per cent in the Flemish part of Belgium, a 2020 review found.

The American Academy of Sleep Medicine (AASM) recommends that 13- to 18-year-olds get eight to ten hours of sleep per night during the week.

The latest study, which was published in the Journal of Child Psychology and Psychiatry, included more than 10,000 participants aged 14 in the United Kingdom. 

They were asked about their sleep problems, including how long they slept on school days, how long it took them to get to sleep, and how often they woke up during the night. 

The 14-year-olds were also asked whether they had deliberately hurt or injured themselves. 

They were asked the same question  again three years later when they were surveyed at age 17.

When young teens got less sleep on school nights, woke up more often overnight, or took longer to fall asleep, they were more likely to report self-harm at ages 14 and 17, the study found.

Sleep problems raised these risks even after the researchers accounted for other known factors, such as age, sex, socioeconomic status, previous instances of self-harm, self-esteem, and depression.

It’s still not clear exactly why there appears to be a link between poor sleep and self-harm. The researchers tested whether poor sleep could be linked to worse decision-making, thus raising the risk of self-harm, but this turned out not to be the case.

Even so, researchers noted that sleep is a “modifiable risk factor,” meaning improving teenagers’ sleep quality and length may help reduce the risk of self-harm and have long-lasting benefits.

“While this is clearly an unfavourable relationship … we can actually do something about it,” said Michaela Pawley, one of the study’s authors and a psychology researcher at the University of Warwick.

“If the link between sleep and self-harm holds true and with well-placed interventions in schools and homes, there is a lot we can do to turn the tide,” she added.

If you are contemplating suicide and need to talk, please reach out to Befrienders Worldwide, an international organisation with helplines in 32 countries. Visit befrienders.org to find the telephone number for your location.

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