Matrix-assisted laser desorption/ionization mass spectrometry imaging (MALDI MSI) has become a powerful method for studying the spatial distribution of molecules. Preparation of tissue sections is a critical step for obtaining high-quality imaging data. The thickness of the slice of tissue affects the feature quality of MALDI MSI. However, few studies involved in-depth and systematic examination of slice thickness. Herein, we investigate the effect of tissue slice thickness on MALDI MSI detection. We found that the thicker the slice, the worse the results obtained by MALDI MS, which we attributed to the charging effect. The optimal slice thickness of brain tissue obtained in this work is 2-6 μm. Comparisons of the effects of slice thickness on atmospheric pressure and vacuum MALDI assays indicated that the ion signals and imaging quality of vacuum MALDI were more seriously affected by the thickness, with atmospheric pressure (AP) MALDI having a greater tolerance for slice thickness than vacuum MALDI. The MALDI MSI of peptides after enzymatic digestion of tissue sections of different thicknesses was also studied, revealing that the most suitable tissue thickness for enzyme digestion is about 10 μm. Finally, we optimized the slice thicknesses of six tissues in mice to provide a reference for MALDI MSI studies. It is worth mentioning that in our study the values of slice thickness range from the nanometer level (400 nm) at the minimum to 150 μm at the maximum, values which were unprecedented. Detailed in-depth and systematic studies of slice thickness will promote the development of sample preparation technology of AP and vacuum MALDI MSI, which will provide important references for the selection of tissue section thickness.

Background We aim to evaluate the association between meal intervals and weight trajectory among adults from a clinical cohort. Methods and Results This is a multisite prospective cohort study of adults recruited from 3 health systems. Over the 6-month study period, 547 participants downloaded and used a mobile application to record the timing of meals and sleep for at least 1 day. We obtained information on weight and comorbidities at each outpatient visit from electronic health records for up to 10 years before until 10 months after baseline. We used mixed linear regression to model weight trajectories. Mean age was 51.1 (SD 15.0) years, and body mass index was 30.8 (SD 7.8) kg/m2; 77.9% were women, and 77.5% reported White race. Mean interval from first to last meal was 11.5 (2.3) hours and was not associated with weight change. The number of meals per day was positively associated with weight change. The average difference in annual weight change (95% CI) associated with an increase of 1 daily meal was 0.28 kg (0.02-0.53). Conclusions Number of daily meals was positively associated with weight change over 6 years. Our findings did not support the use of time-restricted eating as a strategy for long-term weight loss in a general medical population.

Microorganisms, including bacteria, viruses, fungi, and other eukaryotes, play critical roles in human health. An altered microbiome can be associated with complex diseases. Intratumoral microbial components are found in multiple tumor tissues and are closely correlated with cancer initiation and development and therapy efficacy. The intratumoral microbiota may contribute to promotion of the initiation and progression of cancers by DNA mutations, activating carcinogenic pathways, promoting chronic inflammation, complement system, and initiating metastasis. Moreover, the intratumoral microbiota may not only enhance antitumor immunity via mechanisms including STING signaling activation, T and NK cell activation, TLS production, and intratumoral microbiota-derived antigen presenting, but also decrease antitumor immune responses and promote cancer progression through pathways including upregulation of ROS, promoting an anti-inflammatory environment, T cell inactivation, and immunosuppression. The effect of intratumoral microbiota on antitumor immunity is dependent on microbiota composition, crosstalk between microbiota and the cancer, and status of cancers. The intratumoral microbiota may regulate cancer cell physiology and the immune response by different signaling pathways, including ROS, β-catenin, TLR, ERK, NF-κB, and STING, among others. These viewpoints may help identify the microbiota as diagnosis or prognosis evaluation of cancers, and as new therapeutic strategy and potential therapeutic targets for cancer therapy.

In β-thalassemia, either γ-globin induction to form fetal hemoglobin (α2γ2) or β-globin repair to restore adult hemoglobin (α2β2) could be therapeutic. ABE8e, a recently evolved adenine base editor variant, can achieve efficient adenine conversion, yet its application in patient-derived hematopoietic stem cells needs further exploration. Here, we purified ABE8e for ribonucleoprotein electroporation of β-thalassemia patient CD34+ hematopoietic stem and progenitor cells to introduce nucleotide substitutions that upregulate γ-globin expression in the BCL11A enhancer or in the HBG promoter. We observed highly efficient on-target adenine base edits at these two regulatory regions, resulting in robust γ-globin induction. Moreover, we developed ABE8e-SpRY, a near-PAMless ABE variant, and successfully applied ABE8e-SpRY RNP to directly correct HbE and IVS II-654 mutations in patient-derived CD34+ HSPCs. Finally, durable therapeutic editing was produced in self-renewing repopulating human HSCs as assayed in primary and secondary recipients. Together, these results support the potential of ABE-mediated base editing in HSCs to treat inherited monogenic blood disorders.

Guillain-Barré Syndrome (GBS) is an immune-mediated polyneuropathy, most often occurring within weeks of an infection. Cases of COVID-19-related GBS have been reported, and the typical presentation is a progressive ascending paralysis. We describe a case of a 40-year-old with recent symptomatic COVID-19 who presented with atypical GBS findings, hand weakness that progressed to tetraplegia within 24 hours. He had hyperreflexia on his initial exam and did not meet diagnostic criteria for GBS. Inconsistent neurological findings with spontaneous improvement of symptoms, unremarkable initial evaluation including lumbar puncture, and anxiety further complicated the diagnosis. On day 6, he was intubated for diaphragmatic paralysis, and repeat lumbar puncture showed albumin-cytologic dissociation. Intravenous immunoglobulin followed by plasmapheresis improved strength and allowed for extubation. This case highlights the difficulty of recognizing heterogenic GBS presentations.

Male androgenetic alopecia is a common condition and represents a major concern for patients who experience this condition. While there are different treatments to stop hair loss and improve hair density, the 5-alpha reductase inhibitors have demonstrated to be effective in improving androgenetic alopecia in men and can maintain a positive response for many years. Oral finasteride 1 mg is a US FDA-approved option, but dutasteride 0.5 mg has been proven to induce better responses, especially in the frontal area. Both have been shown to be safe in clinical trials but there is widespread concern about sexual adverse effects among patients. The use of topical finasteride has increased during the last few years as a useful option to avoid systemic therapy. The efficacy of topical finasteride 0.25% daily has been demonstrated in clinical trials, with a less marked decrease in serum dihydrotestosterone levels than with oral intake. Mesotherapy with dutasteride has also become more widespread recently, although evidence of its effectiveness is limited to retrospective studies in real clinical practice. The use of oral minoxidil in androgenetic alopecia has not been approved by the FDA, however several clinical studies have shown that it is an effective treatment option. The initial dose recommended to treat male hair loss is 2.5 mg daily, although the dose is frequently increased to 5 mg daily. The main adverse effect of oral minoxidil is hypertrichosis, followed by dizziness or lower limb edema, which are much less common. Platelet-rich plasma is a non-pharmacological option to treat male androgenetic alopecia, with some clinical trials demonstrating an improvement in hair count after several months. Among the published studies, the main limitation to compare its efficacy is the heterogeneity of the procedure. The most frequent regimens propose treatment every 4 weeks for 3 months initially to assess the individual response. Another treatment alternative is the use of light devices with wavelengths of between 630 and 660 nm, known as low-level laser therapy. These devices can be used at home every day for 15-30 min. Their efficacy has been shown in a limited number of clinical trials; however, there is a lack of evidence about the efficacy of these devices compared with other medical options or as a complementary therapy in hair loss. The pipeline of potential new treatments for male androgenetic alopecia is strong. Pyrilutamide and GT20029 are being studied as topical antagonists of the androgen receptor, while cetirizine is another topical option with some initial promising results. Furthermore, according to isolated studies with heterogeneous treatment schemes, the use of botulinum toxin in the scalp might improve androgenetic alopecia, and lastly, scalp threading might increase the total hair count as growth factors are released during implantation.

Excess visceral adiposity contributes to elevated cardiometabolic risk, and waist circumference is commonly used as a surrogate measure of visceral adipose tissue. Although regular aerobic exercise is known to improve abdominal obesity, its effect on waist circumference is unclear. A systematic review and meta-analysis was performed to determine (1) the effect of aerobic exercise on waist circumference in adults with overweight or obesity; (2) the association between any change in waist circumference and change in visceral adipose tissue and/or bodyweight with aerobic exercise interventions; and (3) if reductions in waist circumference with exercise are moderated by clinical characteristics or components of aerobic exercise prescription. Twenty-five randomized controlled trials (1686 participants) were included. Regular aerobic exercise significantly reduced waist circumference by 3.2 cm (95% confidence interval [CI] -3.86, -2.51, p ≤ 0.001) versus control. Change in waist circumference was associated with change in visceral adipose tissue (β = 4.02; 95% CI 1.37, 6.66, p = 0.004), and vigorous intensity produced superior reduction (-4.2 cm, 95% CI -4.99, -3.42, p < 0.0001) in waist circumference compared with moderate intensity (-2.50 cm, 95% CI -3.22, -1.79, p = 0.058). These findings suggest regular aerobic exercise results in modest reductions in waist circumference and associated visceral adipose tissue and that higher intensity exercise may offer superior benefit to moderate intensity.

The aim of this study is to review the current evidence on the diagnosis and management of empyema. The American Pediatric Surgical Association Outcomes and Clinical Trials Committee compiled 8 questions to address. A comprehensive review was performed on each topic. Topics included the distinction between parapneumonic effusion and empyema, the optimal imaging modality in evaluating pleural space disease, when and how pleural fluid should be managed, the first treatment option and optimal timing in the management of empyema, the optimal chemical debridement agent for empyema, therapeutic options if chemical debridement fails, therapy for parenchymal abscess or necrotizing pneumonia and duration of antibiotic therapy after an intervention. The evidence was graded for each topic to provide grade of recommendation where appropriate.