Comparative Effectiveness of Cognitive Behavioral Therapy and Behavioral Therapy in Obesity: A Systematic Review and Network Meta-Analysis.

We aimed to evaluate the effects of obesity treatment with behavioral therapy (BT) and cognitive behavioral therapy (CBT) interventions compared with multiple comparators and find effective techniques or combinations of techniques in BT and CBT interventions for weight loss. We systematically searched electronic databases and selected randomized controlled trials using CBT or BT intervention for obesity treatment in overweight adults or adults with obesity without psychological symptoms. Both pairwise meta-analysis and network meta-analysis were performed to comprehensively evaluate the comparative effects between interventions. We classified the techniques used in BT and CBT interventions and compared the treatment effects between techniques. Compared with no treatment as a common comparator, CBT was most effective for weight loss, followed by BT, usual care (UC), and minimal care (MC). CBT was a more effective intervention than BT, but the effect of CBT compared to BT was not remarkable in network estimates. The most used BT techniques were feedback and monitoring, and the most used CBT technique was cognitive restructuring. Our results indicated that CBT and BT are effective interventions for weight loss, and that successful weight loss requires more aggressive interventions such as BT or CBT than MC and UC.

Sarcopenia; functional concerns, molecular mechanisms involved, and seafood as a nutritional intervention - review article.

The fundamental basis for the human function is provided by skeletal muscle. Advancing age causes selective fiber atrophy, motor unit loss, and hybrid fiber formation resulting in hampered mass and strength, thus referred to as sarcopenia. Influence on the loss of independence of aged adults, contribute toward inclined healthcare costs conveys the injurious impact. The current understating of age-related skeletal muscle changes are addressed in this review, and further discusses mechanisms regulating protein turnover, although they do not completely define the process yet. Moreover, the reduced capacity of muscle regeneration due to impairment of satellite cell activation and proliferation with neuronal, immunological, hormonal factors were brought into the light of attention. Nevertheless, complete understating of sarcopenia requires disentangling it from disuse and disease. Nutritional intervention is considered a potentially preventable factor contributing to sarcopenia. Seafood is a crucial player in the fight against hunger and malnutrition, where it consists of macro and micronutrients. Hence, the review shed light on seafood as a nutritional intrusion in the treatment and prevention of sarcopenia. Understanding multiple factors will provide therapeutic targets in the prevention, treatment, and overcoming adverse effects of sarcopenia.

Sleep parameter characteristics of patients with OSA who have retropalatal circumferential narrowing and the clinical significance of lateral pharyngeal wall collapse during sleep.

BACKGROUND: The lateral pharyngeal wall (LPW) is a critical anatomic structure in patients with obstructive sleep apnea (OSA). Resolving the retropalatal circumferential (RC) narrowing caused by combination of both LPW collapse and antero-posterior (AP) narrowing holds promise for surgical treatment of OSA. We sought to determine the clinical characteristics and distinctive alterations in sleep parameters of patients with OSA who have RC narrowing and LPW collapse. METHODS: Drug-induced sleep endoscopy (DISE), polysomnography findings, and sleep questionnaires were reviewed retrospectively in patients with OSA. RESULTS: Of the 106 OSA patients examined, 48% showed RC narrowing and 44% showed AP narrowing at the oropharynx level during sleep while 8% of the patients showed only LPW collapse. Patients with RC narrowing with LPW collapse exhibited a higher BMI than those with AP narrowing only. In addition, patients with RC narrowing showed more aggravated sleep parameters including apneic events than patients with AP narrowing alone. The degree of RC narrowing correlated significantly with the severity of OSA as shown by a higher apnea index and lower oxygen desaturations. CONCLUSIONS: Our clinical findings suggest that the presence of RC narrowing with LPW collapse in OSA is closely related to increased apneic and oxygen desaturation events. RC narrowing with LPW collapse may be targets for surgical correction in patients with OSA to improve therapeutic outcomes.

Location of out-of-hospital cardiac arrest and the awareness time interval: a nationwide observational study.

AIMS: A short awareness time interval (ATI, time from witnessing the arrest to calling for help) and bystander cardiopulmonary resuscitation (CPR) are important factors affecting neurological recovery after out-of-hospital cardiac arrest (OHCA). This study investigated the association of the location of OHCA with the length of ATI and bystander CPR. METHODS: This population-based observational study used the nationwide Korea OHCA database and included all adults with layperson-witnessed OHCA with presumed cardiac aetiology between 2013 and 2017. The exposure was the location of OHCA (public places, private housing and nursing facilities). The primary outcome was short ATI, defined as <4 min from witnessing to calling for emergency medical service (EMS). The secondary outcome was the frequency of provision of bystander CPR. Multivariable logistic regression analysis was performed to evaluate the association of location of OHCA with study outcomes. RESULTS: Of 30 373 eligible OHCAs, 66.6% occurred in private housing, 24.0% occurred in public places and 9.4% occurred in nursing facilities. In 67.3% of the cases, EMS was activated within 4 min of collapse, most frequently in public places (public places 77.0%, private housing 64.2% and nursing facilities 64.8%; p<0.01). The overall rate of bystander CPR was 65.5% with highest in nursing facilities (77.0%), followed by public places (70.1%) and private housing 62.3%; p<0.01). Compared with public places, the adjusted ORs (AORs) (95% CIs) for a short ATI were 0.58 (0.54 to 0.62) in private housing and 0.62 (0.56 to 0.69) in nursing facilities. The AORs (95% CIs) for bystander CPR were 0.75 (0.71 to 0.80) in private housing and 1.57 (1.41 to 1.75) in nursing facilities. CONCLUSION: OHCAs in private housing and nursing facilities were less likely to have immediate EMS activation after collapse than in public places. A public education is needed to increase the awareness of necessity of prompt EMS activation.

Toward Full-Color Electroluminescent Quantum Dot Displays.

Colloidal quantum dots (QDs) exhibit unique characteristics such as facile color tunability, pure color emission with extremely narrow bandwidths, high luminescence efficiency, and high photostability. In addition, quantum dot light-emitting diodes (QLEDs) feature bright electroluminescence, low turn-on voltage, and ultrathin form factor, making them a promising candidate for next-generation displays. To achieve the overarching goal of the full-color display based on the electroluminescence of QDs, however it is essential to enhance the performance of QLEDs further for each color (e.g., red, green, and blue; RGB) and develop novel techniques for patterning RGB QD pixels without cross-contamination. Here, we present state-of-the-art material, process, and device technologies for full-color QLED-based displays. First, we highlight recent advances in the development of efficient red-, green-, and blue-monochromatic QLEDs. In particular, we focus on the progress of heavy-metal-free QLEDs. Then, we describe patterning techniques for individual RGB QDs to fabricate pixelated displays. Finally, we briefly summarize applications of such QLEDs, presenting the possibility of full-color QLED-based displays.

Effect of Pinoresinol and Vanillic Acid Isolated from Catalpa bignonioides on Mouse Myoblast Proliferation via the Akt/mTOR Signaling Pathway.

Growth and maintenance of skeletal muscle is essential for athletic performance and a healthy life. Stimulating the proliferation and differentiation of muscle cells may help prevent loss of muscle mass. To discover effective natural substances enabling to mitigate muscle loss without side effects, we evaluated muscle growth with several compounds extracted from Catalpa bignonioides Walt. Among these compounds, pinoresinol and vanillic acid increased C2C12, a mouse myoblast cell line, proliferation being the most without cytotoxicity. These substances activated the Akt/mammalian target of the rapamycin (mTOR) pathway, which positively regulates the proliferation of muscle cells. In addition, the results of in silico molecular docking study showed that they may bind to the active site of insulin-like growth factor 1 receptor (IGF-1R), which is an upstream of the Akt/mTOR pathway, indicating that both pinoresinol and vanillic acid stimulate myoblast proliferation through direct interaction with IGF-1R. These results suggest that pinoresinol and vanillic acid may be a natural supplement to improve the proliferation of skeletal muscle via IGF-1R/Akt/mTOR signaling and thus strengthen muscles.

Removal of pharmaceuticals and personal care products using native fungal enzymes extracted during the ligninolytic process.

Significant concentrations of pharmaceuticals and personal care products (PPCPs) have been detected in aquatic environment. Fungal enzymatic processes can oxidize these persistent PPCPs; thus, these processes have attracted considerable attention from the scientific community. Here, we evaluated the efficacy of the removal of PPCPs using native fungal enzymes derived from Bjerkandera spp. TBB-03 under various conditions. Among the eight lignocellulosic substrates, ash, which showed the highest laccase production, was selected as the sole enzyme inducer. TBB-03 laccase was found to exhibit remarkable stability under varied pH and temperature conditions. Acetaminophen and bisphenol A were effectively removed by TBB-03 laccase under various conditions, except at pH 8. Although TBB-03 laccase could not efficiently remove single-state sulfamethoxazole directly, a 22% of improvement in sulfamethoxazole removal was observed in the presence of acetaminophen. Overall, our proposed approach showed that Bjerkandera adusta TBB-03 can be potentially applied for further research regarding PPCP remediation.

The Effects of Marine Algal Polyphenols, Phlorotannins, on Skeletal Muscle Growth in C2C12 Muscle Cells via Smad and IGF-1 Signaling Pathways.

Skeletal muscle is an important tissue in energy metabolism and athletic performance. The use of effective synthetic supplements and drugs to promote muscle growth is limited by various side effects. Moreover, their use is prohibited by anti-doping agencies; hence, natural alternatives are needed. Therefore, we evaluated the muscle growth effect of substances that can act like synthetic supplements from edible marine algae. First, we isolated six marine algal polyphenols belonging to the phlorotannin class, namely dieckol (DK), 2,7″-phloroglucinol-6,6'-bieckol (PHB), phlorofucofuroeckol A (PFFA), 6,6'-bieckol (6,6-BK), pyrogallol-phloroglucinol-6,6'-bieckol (PPB), and phloroglucinol (PG) from an edible brown alga, Ecklonia cava and evaluated their effects on C2C12 myoblasts proliferation and differentiation. Of the six phlorotannin isolates evaluated, DK and PHB induced the highest degree of C2C12 myoblast proliferation. In addition, DK and PHB regulates myogenesis by down-regulating the Smad signaling, a negative regulator, and up-regulating the insulin-like growth factor-1 (IGF-1) signaling, a positive regulator. Interestingly, DK and PHB bind strongly to myostatin, which is an inhibitor of myoblast proliferation, while also binding to IGF-1 receptors. Moreover, they bind to IGF-1 receptor. These results suggest that DK and PHB are potential natural muscle building supplements and could be a safer alternative to synthetic drugs.

Effectiveness of Chin Tuck on Laryngeal Penetration: Quantitative Assessment.

The effectiveness of the chin tuck maneuver is still controversial, despite being widely used in clinical practice. The chin tuck maneuver has been shown to be able to reduce or eliminate aspiration in a group of patients with a number of favorable conditions, but its effectiveness in preventing or managing penetration remains unclear. This study was designed to investigate whether the chin tuck maneuver is effective in reducing penetration. Images from a videofluoroscopic swallowing study (VFSS) taken from 76 patients with penetration were collected and reviewed retrospectively. The severity of penetration was assessed by the penetration ratio (ratio of the penetration depth to the length of the epiglottis) measured and calculated from the images in which the deepest penetration was observed. The penetration ratio was significantly decreased in the chin tuck posture compared with the ratio in the neutral position (p = 0.001). Significant reducing effect was observed in 26 (34.2%) out of 76 patients. When comparing other parameters of VFSS, residues in the vallecular and pyriformis sinuses were less severe in the effective group. Chin tuck significantly decreased residues in both effective and ineffective group. The results demonstrate that the chin tuck maneuver can reduce penetration, but its effectiveness is limited.

Phytochemicals in Chinese Chive (Allium tuberosum) Induce the Skeletal Muscle Cell Proliferation via PI3K/Akt/mTOR and Smad Pathways in C2C12 Cells.

Chinese chive (Allium tuberosum) is a medicinal food that is cultivated and consumed mainly in Asian countries. Its various phytochemicals and physiological effects have been reported, but only a few phytochemicals are available for skeletal muscle cell proliferation. Herein, we isolated a new compound, kaempferol-3-O-(6″-feruloyl)-sophoroside (1), along with one known flavonoid glycoside (2) and six amino acid (3-8) compounds from the water-soluble fraction of the shoot of the Chinese chive. The isolated compounds were identified using extensive spectroscopic methods, including 1D and 2D NMR, and evaluated for their proliferation activity on skeletal muscle cells. Among the tested compounds, newly isolated flavonoid (1) and 5-aminouridine (7) up-regulated PI3K/Akt/mTOR pathways, which implies a positive effect on skeletal muscle growth and differentiation. In particular, compound 1 down-regulated the Smad pathways, which are negative regulators of skeletal muscle growth. Collectively, we suggest that major constituents of Chinese chive, flavonoids and amino acids, might be used in dietary supplements that aid skeletal muscle growth.

Diphlorethohydroxycarmalol (DPHC) Isolated from the Brown Alga Ishige okamurae Acts on Inflammatory Myopathy as an Inhibitory Agent of TNF-α.

Inflammation affects various organs of the human body, including skeletal muscle. Phlorotannins are natural biologically active substances found in marine brown algae and exhibit anti-inflammatory activities. In this study, we focused on the effects of phlorotannins on anti-inflammatory activity and skeletal muscle cell proliferation activity to identify the protective effects on the inflammatory myopathy. First, the five species of marine brown algal extracts dramatically inhibited nitric oxide (NO) production in lipopolysaccharide (LPS)-induced RAW 264.7 cells without toxicity at all the concentrations tested. Moreover, the extracts collected from Ishige okamurae (I. okamurae) significantly increased cell proliferation of C2C12 myoblasts compared to the non-treated cells with non-toxicity. In addition, as a result of finding a potential tumor necrosis factor (TNF)-α inhibitor that regulates the signaling pathway of muscle degradation in I. okamurae-derived natural bioactive compounds, Diphlorethohydroxycarmalol (DPHC) is favorably docked to the TNF-α with the lowest binding energy and docking interaction energy value. Moreover, DPHC down-regulated the mRNA expression level of pro-inflammatory cytokines and suppressed the muscle RING-finger protein (MuRF)-1 and Muscle Atrophy F-box (MAFbx)/Atrgoin-1, which are the key protein muscle atrophy via nuclear factor-κB (NF-κB), and mitogen-activated protein kinase (MAPKs) signaling pathways in TNF-α-stimulated C2C12 myotubes. Therefore, it is expected that DPHC isolated from IO would be developed as a TNF-α inhibitor against inflammatory myopathy.

1-Cinnamoyltrichilinin from Melia azedarach Causes Apoptosis through the p38 MAPK Pathway in HL-60 Human Leukemia Cells.

Acute myeloid leukemia (AML) is an aggressive type of human leukemia with a low survival rate, and its complete remission remains challenging. Although chemotherapy is the first-line treatment of AML, it exerts toxicity in noncancerous cells when used in high doses, thus necessitating the development of novel compounds with a high therapeutic window. This study aimed to investigate the anticancer effects of several compounds derived from the fruits of Melia azedarach (a tree with medicinal properties). Among them, 1-cinnamoyltrichilinin (CT) was found to strongly suppress the viability of HL-60 human leukemia cells. CT treatment induced apoptosis and increased nuclear fragmentation and fractional DNA content in HL-60 cells in a dose-dependent manner. CT induced phosphorylation of p38 mitogen-activated protein kinases (p38), though not of c-Jun N-terminal kinase (JNK) and extracellular signal-regulated kinase (ERK), and activated Bcl-2 family proteins towards the proapoptosis and cleavage of caspase-3 and poly (ADP-ribose) polymerase. Both CT-mediated apoptosis and apoptotic protein expression were reversed by treatment with the p38 inhibitor, thereby indicating the p38 pathway to be critical in CT-stimulated apoptosis. The results collectively indicated CT to suppress HL-60 survival by activating the p38 pathway and inducing apoptosis, hence being a novel potential therapeutic agent for AML.

Gas formation and biological effects of biodegradable magnesium in a preclinical and clinical observation.

Magnesium alloys are biodegradable metals receiving increasing attention, but the clinical applications of these materials are delayed by concerns over the rapid corrosion rate and gas formation. Unlike corrosion, which weakens mechanical properties, the gas formation issue has received little attention. Therefore, we evaluated the gas formation and biological effects for Mg implants through preclinical (immersed in Earle's balanced salt solution and in vivo) and clinical studies. The immersion test examined the gas volume and composition. The in vivo study also examined gas volume and histological analysis. The clinical study examined the gas volume and safety after Mg screw metatarsal fixation. Gas was mainly composed of H2, CO and CO2. Maximum volumes of gas formed after 5 days for in vivo and 7 days in clinical study. Within the clinical examination, two superficial wound complications healed with local wound care. Osteolytic lesions in the surrounding metaphysis of the Mg screw insertion developed in all cases and union occurred at 3 months. Mg implants released gas with variable volumes and composition (H2, CO, and CO2), with no long-term toxic effects on the surrounding tissue. The implants enabled bone healing, although complications of wound breakdown and osteolytic lesions developed.

The roles of NF-κB and ROS in regulation of pro-inflammatory mediators of inflammation induction in LPS-stimulated zebrafish embryos.

In this study, the roles of reactive oxygen species (ROS) and NF-κB on inflammation induction in lipopolysaccharide (LPS)-stimulated zebrafish embryos were evaluated using N-acetyl-l-cysteine (NAC) and pyrrolidine dithiocarbamate (PDTC), specific inhibitors of ROS and NF-κB, respectively. LPS-stimulated zebrafish embryos showed increasing production of NO and ROS and expression of iNOS and COX-2 protein, compared to a control group without LPS. However, NAC significantly inhibited production of NO and ROS and markedly suppressed expression of iNOS and COX-2 protein in LPS-stimulated zebrafish embryos. The mRNA expressions of NF-κB such as p65NF-κB and IκB-A were significantly increased after LPS stimulation, whereas PDTC attenuated mRNA expression of NF-κB. PDTC also inhibited production of NO and reduced expression of iNOS and COX-2 protein in LPS-stimulated zebrafish embryos. Taken together, these results indicated that LPS increases pro-inflammatory mediators in zebrafish embryos through ROS and NF-κB regulation.

The Conjugated Double Bond of Coniferyl Aldehyde Is Essential for Heat Shock Factor 1 Mediated Cytotoprotection.

Coniferyl aldehyde (1) is previously reported as a potent inducer of heat shock factor 1 (HSF1). Here, we further examined the active pharmacophore of 1 for activation of HSF1 using the derivatives coniferyl alcohol (2), 4-hydroxy-3-methoxyphenylpropanal (3), and 4-hydroxy-3-methoxyphenylpropanol (4). Both 1 and 2 resulted in increased survival days after a lethal radiation (IR) dose. The decrease in bone marrow (BM) cellularity and Ki67-positive BM cells by IR was also significantly restored by 1 or 2 in mice. These results suggested that the vinyl moiety of 1 and 2 is necessary for inducing HSF1, which may be useful for developing small molecules for cytoprotection of normal cells against damage by cytotoxic drugs and radiation.

Innovative AI methods for monitoring front-of-package information: A case study on infant foods.

Front-of-package (FOP) is one of the most direct communication channels connecting manufacturers and consumers, as it displays crucial information such as certification, nutrition, and health. Traditional methods for obtaining information from FOPs often involved manual collection and analysis. To overcome these labor-intensive characteristics, new methods using two artificial intelligence (AI) approaches were applied for information monitoring of FOPs. In order to provide practical implementations, a case study was conducted on infant food products. First, FOP images were collected from Amazon.com. Then, from the FOP images, 1) the certification usage status of the infant food group was obtained by recognizing the certification marks using object detection. Moreover, 2) the nutrition and health-related texts written on the images were automatically extracted based on optical character recognition (OCR), and the associations between health-related texts were identified by network analysis. The model attained a 94.9% accuracy in identifying certification marks, unveiling prevalent certifications like Kosher. Frequency and network analysis revealed common nutrients and health associations, providing valuable insights into consumer perception. These methods enable fast and efficient monitoring capabilities, which can significantly benefit various food industries. Moreover, the AI-based approaches used in the study are believed to offer insights for related industries regarding the swift transformations in product information status.

Polycaprolactone-MXene coating for controlling initial biodegradation of magnesium implant via near-infrared light.

The mechanical strength of magnesium implants undergoes a rapid decline after implantation due to bioabsorption, which can lead to the risk of rupture. To ensure sustained mechanical strength and initiate bioabsorption selectively upon specific external stimuli until the bone regains sufficient support, we developed a biosafe near-infrared light (NIR)-sensitive polymer coating using polycaprolactone (PCL) and Ti3C2 (MXenes). The synthetic MXene powders were characterized using SEM, EDS, and XRD, and the amount of MXenes had a proliferation-promoting effect on MC3T3-E1, as observed through cell assays. The PCL-MXene coating was successfully prepared on the magnesium surface using the casting coating method, and it can protect the magnesium surface for up to 28 days by decreasing the corrosion ratio. However, the coating can be easily degraded after exposure to NIR light for 20 minutes to expose the magnesium substrate, especially in a liquid environment. Meanwhile, the magnesium implant with the PCL-MXene coating has no cytotoxicity toward MC3T3-E1. These findings can provide a new solution for the development of controlled degradation implants.

Diagnostic value of a deep learning-based hyoid bone tracking model for aspiration in patients with post-stroke dysphagia.

Objective: Hyoid bone movement is potentially related to aspiration risk in post-stroke dysphagia (PSD) patients but is difficult to assess quantitatively. This study aimed to measure the distance of hyoid bone movement more efficiently and accurately using a deep learning model and determine the clinical usefulness of the model in PSD patients. Methods: This study included 85 patients with PSD within 6 months from onset. Patients were grouped into an aspiration group (n = 35) and a non-aspiration group (n = 50) according to the results of a videofluoroscopic swallowing study. Hyoid bone movement was tracked using a deep learning model constructed with the BiFPN-U-Net(T) architecture. The maximum distance of hyoid bone movement was measured horizontally (H max), vertically (V max), and diagonally (D max). Results: Compared with the non-aspiration group, the aspiration group showed significant decreases in hyoid bone movement in all directions. The area under the curve of V max was highest at 0.715 with a sensitivity of 0.680 and specificity of 0.743. The V max cutoff value for predicting aspiration risk was 1.61 cm. The success of oral feeding at the time of discharge was significantly more frequent when hyoid movement was equal to or larger than the cutoff value although no significant relationship was found between hyoid movement and other clinical characteristics. Conclusion: Hyoid bone movement of PSD patients can be measured quantitatively and efficiently using a deep learning model. Deep learning model-based analysis of hyoid bone movement seems to be useful for predicting aspiration risk and the possibility of resuming oral feeding.

Asbestos Exposure and Ovarian Cancer: A Meta-analysis.

Background: The International Agency for Research on Cancer (IARC) Monograph conducted a systematic review of the relationship between asbestos and ovarian cancer. However, there may have been information bias due to the undue weight given to few articles. To address this limitation, the present study performed a meta-analysis integrating studies published both before and after the 2012 IARC Monograph on Asbestos, with the aim of investigating the association between asbestos exposure and ovarian cancer. Methods: A comprehensive search of major journal databases was conducted to identify studies examining the relationship between asbestos exposure and ovarian cancer, including those featured in the 2012 IARC Monograph on Asbestos. A meta-analysis on asbestos exposure and cancer risk was performed. Results: The meta-analysis of studies published after the 2012 IARC Monograph on Asbestos found a summary Standardized Mortality Ratio (SMR) of 2.04 (95% CI: 1.03-4.05; p = 0.0123; 5 studies), with a significant degree of heterogeneity among the studies (I2 = 72.99%). The combined analysis of 15 studies before and after the 2012 IARC Monograph showed an overall summary SMR of 1.72 (95% CI: 1.43-2.06; p = 0.0349; 15 studies), with a moderate degree of heterogeneity (I2 = 42.99%). Conclusion: This meta-analysis provides evidence of a significant association between asbestos exposure and ovarian cancer mortality. While the possibility of misdiagnosis in earlier studies cannot be completely ruled out, recent findings suggest a robust correlation between asbestos exposure and ovarian cancer. This highlights the importance of sustained efforts to minimize asbestos exposure and protect public health.

Revealing Two Distinct Formation Pathways of 2D Wurtzite-CdSe Nanocrystals Using In Situ X-Ray Scattering.

Understanding the mechanism underlying the formation of quantum-sized semiconductor nanocrystals is crucial for controlling their synthesis for a wide array of applications. However, most studies of 2D CdSe nanocrystals have relied predominantly on ex situ analyses, obscuring key intermediate stages and raising fundamental questions regarding their lateral shapes. Herein, the formation pathways of two distinct quantum-sized 2D wurtzite-CdSe nanocrystals - nanoribbons and nanosheets - by employing a comprehensive approach, combining in situ small-angle X-ray scattering techniques with various ex situ characterization methods is studied. Although both nanostructures share the same thickness of ≈1.4 nm, they display contrasting lateral dimensions. The findings reveal the pivotal role of Se precursor reactivity in determining two distinct synthesis pathways. Specifically, highly reactive precursors promote the formation of the nanocluster-lamellar assemblies, leading to the synthesis of 2D nanoribbons with elongated shapes. In contrast, mild precursors produce nanosheets from a tiny seed of 2D nuclei, and the lateral growth is regulated by chloride ions, rather than relying on nanocluster-lamellar assemblies or Cd(halide)2 -alkylamine templates, resulting in 2D nanocrystals with relatively shorter lengths. These findings significantly advance the understanding of the growth mechanism governing quantum-sized 2D semiconductor nanocrystals and offer valuable guidelines for their rational synthesis.